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'''Because the steps are made of a smooth, polished—and therefore slippery—stone, the BTA should’ve taken precautions to clean the steps in such wintry conditions.
Accessibility is quite a key factor because it is evident that the regional centre was built on the basis of good infrastructure.
Because of the event happening next year, the housing prices have gone up so rapidly around here.
Given that about a quarter of all employed people move on and off the payrolls of individual firms during the year , a need to move between firms to climb the career ladder would not seem to be a difficult barrier to surmount .
The Act required that the application should be dealt with in a public hearing … Thus there is the penalty of public exposure and humiliation
The lack of connection between the SLA theories, which tend to be English or European languages based, and the Japanese teaching that is found in JLT is probably due to a lack of attention to pragmatic and sociocultural aspects of Japanese language and communication.
Perhaps due to a seeming disconnect between written and oral output, only a handful of studies to date have examined the potential impact of SCMC on oral language proficiency.
It doesn’t make a great deal of sense to claim that some things are wrong, primarily on the grounds that, like Mackie, I don’t believe that such qualities exist.''',
'''Breitman, in his article Plans for the Final Solution, refers to the controversy about the origins of the Holocaust as the “intentionalist-functionalist” debate; that is one between those who think the Holocaust was a preconceived Nazi plan, and those who think it was improvised hastily, notably after early German victories in the Soviet Union in mid-1941. Breitman, in contrast to Browning, is very much an ‘intentionalist’, arguing that the ‘murderous intentions’ of Hitler, Himmler and other key Nazis were well underway before the invasion of the Soviet Union. Whilst he admits that many of the Nazi documents on this issue are “inexact”, he suggests that this is not because the Holocaust plan itself was uncertain, but rather because the Nazi leadership wanted to “conceal” and “veil” its real intentions from others (p. 271). To support his case for pre-planning, Breitman relies on two main sources of evidence: memos from two officials in the Nazi Jewish Office at the time – Adolf Eichmann and Theodore Dannecker; and the Nuremberg testimony of Viktor Brack, an official in the Fuhrer Chancellery. The memos in question indicate that high-level discussion of some form of ‘final solution’ did take place early in 1941. Danneker’s memo in January 1941 disclosed that Hitler wanted a ‘final solution’ of the Jewish question. A month later, Eichmann in a meeting at the Propaganda Office announced to rival bureaucrats that Hitler was determined to implement a ‘final evacuation’ of the Jews. The problem however, with such evidence is that there is doubt among historians about what these terms actually meant at the time. ‘Final solution’ and ‘final evacuation’ may have been code words for mass extermination, but they may equally have referred to some less murderous Nazi policies. It was known for example, that other options being considered around this time were the mass deportations of Jews to Madagascar, and also mass sterilisation. Breitman’s argument relies on an assumption that these terms could refer only to what later became the Holocaust. He states that to require ‘an unambiguous blueprint for extermination’ from the Nazi archives is asking for an impossible standard of proof (p. 274). But, unfortunately no such document has been uncovered by historians and so, we have to be cautious about how we interpret Nazi intentions at the time.
''',
'''Many educational reformers, particularly those associated with the standards movement, hold that the key to improving student performance lies in improving the schools. If academic standards are rigorous, if curriculum and assessments are aligned to those standards, and if teachers possess the skills to teach at the level the standards demand, student performance will improve. However, this perspective is to some extent at odds with another that has emerged from the discussion about school improvement, namely that it is students rather than schools that make the difference. Hence, a New York Times story on how to improve the academic performance of low-income students can include the headline: "What No School Can Do (Traub, 2000)”. Or,as Laurence Steinberg puts it in Beyond the Classroom: Why School Reform has Failed and What Parents Need to Do, “neither the source of our achievement problem, nor the mechanism through which we can best address it, is to be found by examining or altering schools (Steinberg, 1996, p. 60)”. In this view, it is the social backgrounds of students that play the key role in their ability to learn, and only by moving outside of the educational system and attacking the pervasive economic inequalities that exist in the U.S. can student performance be improved.''',
'''Quantitative research on whether schools matter has generally supported the notion that the problems of U.S. education lie outside of the schools. Some research finds that when the social backgrounds of students are taken into account, school characteristics do not seem to influence student outcomes, suggesting that schools do not serve as avenues for upward mobility, but instead reinforce existing social and economic inequalities (Coleman et al., 1966; Jencks et al., 1972). Other researchers contend that school characteristics can have a greater effect on student outcomes than would be expected based upon student background (Lee, Bryk and Smith, 1993)... But while the research in support of this contention does find significant effects for school characteristics, the magnitudes of these effects tend to be modest, far overshadowed by the effects of student background characteristics. A possible reason for the lack of large school effects in quantitative research is the failure of such research to capitalize on an insight from qualitative research: the central importance of the classroom practices of teachers.''',
'''Latour and Woolgar's (1986) seminal study provides an ethnographic account of the scientific writing cycle in a professional laboratory. They document how scientists transform raw data by putting them into charts and graphs, and subsequently use them along with articles, books, and grant proposals to produce new articles. In turn, the articles are circulated to colleagues, submitted for publication, and, when published, often become part of the received body of knowledge. Their study demonstrates the importance of writing about laboratory findings, shows that writing becomes an objectified representation of hours of scientific work, and is a major part of what scientists do.''',
'''The disadvantage experienced by scholars who use English as an Additional Language (EAL) in writing for publication has been well documented both in the field of applied linguistics (e.g., Ammon, 2000, 2001; Belcher, 2007; Burrough-Boenisch, 2003; Flowerdew, 1999a, 1999b; Gosden, 1995; Kaplan & Baldauf, 2005; St. John, 1987) and that of science (e.g., Benfield & Feak, 2006; Benfield & Howard, 2000; Coates, Sturgeon, Bohannan, & Pasini, 2002; Kirkman, 1996). As well as needing more time to write (e.g., Curry & Lillis, 2004; Flowerdew, 1999a, 1999b; Lillis & Curry, 2006), EAL writers may encounter difficulties with reviewers and editors if their use of English is 'non-standard.' While there is some evidence of journal editors' and reviewers' tolerance of non-native features in EAL authors' submissions (Flowerdew, 2001), there are also reports of such gatekeepers criticizing these features. Ammon (2000, p. 113), for example, as a German editor of a book published in English, reports on criticisms of his work .''',
'''To a significant extent, individuals can be considered responsible for the rise of Hitler to power on the 31st of January, 1933. Hitler himself, the charismatic leader of the Nazi Party, as well as creator of Nazi policy, played a key role in his own rise to power. However, other individuals in government, such as Hindenburg and von Papen were influential in Hitler's rise. To a small extent, other factors also enabled Hitler to rise to power such as the Depression and the weakness of the political system. Nevertheless to a significant extent, individuals can be held responsible for the rise of Adolf Hitler to power.''',
'''Teachers are facing the difficult task of providing an optimal learning environment to students from varying social, cultural, and linguistic backgrounds. From their side, minority students may have different experiences in the same classroom than their native classmates. For instance, they may have difficulty in understanding teacher instructions and in structuring school tasks, and hence use less effective learning strategies (Tharp, 1989). Not only task aspects but also relational and cultural aspects of the classroom environment come into play. For example, negative teacher stereotypes of minority students as lazy or dumb may become self-fulfilling prophecies (Steele and Aronson, 1995). Furthermore, repeated experiences of school failure may threaten the self-esteem of disadvantaged minority youth, leading to disengagement with learning (Okagaki et al., 1996). Some minority students may lack social or cultural skills to participate actively in classroom interactions (Connell et al., 1994). Others may actively oppose or resist schoolwork as a reaction against perceived ethnic discrimination by teachers or peers (Ogbu and Simons, 1998)''',
'''It is argued that future goals may fail to motivate school achievement for two main reasons: Because students may not perceive a clear positive connection between doing well in school and success later in life; and because they may not experience future goals as internally driven or self-set goals but rather as externally controlled or imposed from the outside. Extending recent motivational research to minority students’ school achievement, we conclude that future goals will motivate achievement in multicultural classrooms, provided that schools and families succeed in fostering internal regulation along with positive perceptions of instrumentality.''',
'''As I entered the classroom with its glaring fluorescent lights, I noticed how the desks were arranged into a circle, and a table pulled from its position at the edge of the room, was now filled with cakes, cups, jugs of juice, and plates of cookies. I waved hello to Ramona and Cindy who were surrounded by other American Indian women, and I slid into one of the seats. The room was awash with conversation interspersed with laughter and I felt my weariness melt as students said hello to me.''',
'''Tickner said regardless of the result, the royal commission was a waste of money and he would proceed with a separate inquiry into the issue headed by Justice Jane Matthews. His attack came as the Aboriginal women involved in the case demanded a female minister examine the religious beliefs they claim are inherent in their fight against a bridge to the island near Goolwa in South Australia.''',
'''Certainly, the argumentation is not without some faults. For example, the statement that “linking homosexuality to witches fulfills the same purpose” is not supported by references to the readings. It is not clear who was linking homosexuality to witches and in what context. Nevertheless, overall and in line with the general tendencies reported in the previous section, the author employs various contracting and expanding engagement resources successfully. However, a large part of the successful use of engagement resources seems to be related to how the author structures these strategies throughout the text, namely in a wave-like fashion: from acknowledging the opinions of others, to countering them by offering one’s own interpretation, to supporting it by acknowledging other sources.''',
'''Despite these advances, it was not until the twentieth century that midwifery became recognised as central to general practice (Moscucci, 1990), and qualifications were deemed necessary to practice of midwifery, with the 1902 Midwives Act (Oakley, 1984).
This resulted in women being further pushed out of an area which they had continued to dominate, despite the professionalisation of the rest of medicine.
This also had class implications, as although women were accepted by lying-in hospitals to train in midwifery they had to pay for the privilege, ensuring that it was only those from the skilled classes who could qualify (Donnison, 1993). Previously, midwifery had been based largely on experience rather than qualification, so was practiced by many working-class women.''',
'''As the centuries passed, accounts of witchcraft became more and more specific; details of witches’ ceremonies and oaths became more concrete and whatever the condemned humans confessed to was treated as fact. As discussants correctly pointed out, Bernardino of Siena, Martin Le Franc, and the anonymous author of the Errores Gazariorum all have an even more aggressive campaign against witches than did the authors of our previous readings. By depicting their rituals and customs, they look to paint the most grotesque picture of witches possible. Their frenzied accusations, were some of the main catalysts of the subsequent witch hunts.''',
'''The post labeled “Witchcraft as a Problem in Society” clearly explains the contribution that each text makes to the witch hunts. While two of the authors focused on describing, in full detail, the shocking and disturbing practices that witches partook of, the others tried to prove that the witch threat was real. These last texts sought to explain witchcraft so as to convince readers that witches actually existed. As all posts reiterate, the devil is definitely at the source of witchcraft.''',
'''The third part temporarily puts aside mediation analysis and shifts the discussion to moderation analysis. In Chapter 7, I show how a multiple regression model can be made more flexible by allowing one variable’s effect to depend linearly on another variable in the model. The resulting moderated multiple regression model allows an investigator to ascertain the extent to which X’s influence on outcome variable Y is contingent on or interacts with a moderator variable W.''',
'''For instance, research has shown that people have a tendency to justify close others’ unethical actions to protect them (Gino and Galinsky 2012). Research has also shown that parents who feel close to their children often adopt strict curfew practices (Elder et al., 1995). (EC-33)''',
'''Fitzpatrick and Pagani (2013) found that engagement skills in classroom behaviour at kindergarten were related with better math scores and academic success. (LC-0525-EN)''',
'''As far as I am concerned, I do think globalization is good chance for China’s developing. From my point of view, I prefer to think that advantages of globalization outweighs disadvantages. ''',
'''As we know, China has made great progress for these years. I think it is the result of globalization. We all know China is a fast-developing country. We can seethe great progress that China has made. ''',
'''His idea was that an important ninth century bishop called John Anglicus may indeed have given birth to a child in full view of everyone on the streets of Rome, but that this bishop was not and never had been the pope. Of course, there is no evidence whatever for this, as Leibnitz himself well knew.''',
'''On the whole, however, when evaluating meanings metaphorically, the Chinese EFL learners hedge and qualify their statements subjectively, tempering the certainty and authority of their assertions rather than using the resources of interpersonal metaphor to reinforce and substantiate their arguments. These tendencies reveal a key area for pedagogical intervention. Namely, instruction could focus on the value of construing metaphors objectively to obscure the author as the source of the evaluation. Similarly, raising students’ awareness of the space of negotiation and the value of offering assertions on a cline of certainty (e.g., IT IS EVIDENT) rather than through exclusive declarations of shared knowledge (e.g., AS WE ALL KNOW) is critical for academic writing refinement. Instructional interventions such as these are key areas for further investigation.''',
'''Of the defendants involved in Utah Pie Company’s case only one seems to have emerged as exceptionally successful. However this success was not a factor of overwhelming market power, as can be seen by the dominant position of Mrs. Smith’s during this time, which had maintained a 39-45 percent market share over the corresponding period.''',
'''Because of the evidence presented by Tremblay and Tremblay, it would appear that mergers in the brewing industry would have been procompetitive because of economies of scale. However, allowing a firm to acquire more than 20% of the market in Wisconsin would give it too much power to charge higher prices, even if the merger would help lower total average costs.''',
'''Taken in whole, the economic evidence for grocery retailers in the decades after the Von’s decision suggests that increased concentration is pro-competitive and good for consumers, running contrary to the fears proposed by the Court.''',
'''The remedies that Justice Lewis Powell prescribed did not gain the desired effect, and I feel that they were not very effective in promoting competition. (Elan, S86)''',
'''There is the possibility for abuse if the producer sets different maximum prices for different retailers, allowing some to reap higher profits.''',
'''Such a program, with appropriate limits, would provide a balanced structure that would ensure quality patient care.''',
'''A recent survey of physician satisfaction by Harvard Medical School found that physician autonomy and the ability to provide high-quality care, not income, are most strongly associated with changes in job satisfaction . Thus, it seems reasonable to assume that health care providers would take advantage of the greater bargaining power to improve the quality of care. (Ken, S78-79)''',
'''It appears, then, that maximum price fixing does the greatest harm when set below a competitive level [evidentialize]. In Case 4 it could potentially do harm to small retailers trying to enter the market [suggest], but does so for the benefit of consumers and the producer. Based purely on the models, it appears that, at the very least, maximum prices deserve a Rule of Reason approach to evaluate their cost and benefits.''',
'''It could be seen that for this 68% of the respondents, Tampines was characteristically a location that provided for them all their basic needs. It can be seen from chart [11] that many people quoted accessibility and proximity to home, and even shopping as one of the ideal factors that drew them there. Accessibility is quite a key factor because it is evident that the regional centre was built on the basis of good infrastructure. In comparison, 32% of the respondents felt that the conventional downtown was still a major attraction, even though the regional centre had gained quite a vast amount of popularity and did to large extent have an air of modernity.'''
'''Sociologists have traditionally been divided into two groups depending upon their ontological position; Individualists emphasise the importance of an individual's action, whilst Collectivists give primacy to the role of social structure in the construction of social reality.
Recently, however, these rigidly demarcated ontological positions have been challenged by the emergence of Realism and Structuration Theory.
This essay is concerned with assessing the strengths and weaknesses of Individualism and Collectivism; the main issue under consideration is how far these opposing ontologies disprove each other.
This essay will argue that neither of these ontologies sufficiently describes or explains the complexity of social reality, and it is because of their deficiencies that I have been persuaded to adopt a Realist perspective.
This argument will be pursued by outlining the debate between Nicos Poulantzas and Ralph Miliband concerning who or what constitutes the 'Ruling Class', in order to show how I was first alerted to the stratified nature of social realty.
It will then be discussed how Collectivism successfully discredits the methodological premises of Individualism, yet does not constitute a comprehensive ontological alternative.
Following this will be a description of how Realism provides the ontological explanations that Collectivism cannot (due to Collectivism's grounding in Empiricism).
Finally, the decision to adopt a Realist approach instead of supporting Structuration Theory will then be justified.
The essay begins by proving that having an ontology is not an option.
--- Para SEP ---
Having a view of social reality is a prerequisite for both constructing a methodology and conducting research.
The role of the researcher's ontology is to regulate which explanations for social phenomena are acceptable; this therefore determines the researcher's area of focus and influences how they devise their practical social theories (Archer, 1995; 20-21).
This means that the Individualist's premise that social reality is ultimately constituted by individuals determines that their explanations must consist of statements about a person's 'dispositions, beliefs, resources and interaction' (Watkins, 1971; 106).
Similarly, the Collectivist's belief that society has structural features which cannot be reduced to the dispositions of individuals determines that their explanations of human action must refer to the influence of non-human features (such as the banking system) (Mendelbaum, 1973; 223-224).
Therefore, practical social theories are only considered acceptable if they are predicated upon the explanations (or methodology) generated by the researcher's description of social reality (their ontology) (Archer, 1995; 21).
Having a theoretical starting point when conducting research is vital because researchers who perform data collection and then generate their theories (through inductive reasoning or the grounded theory approach) inevitably reproduce the stereotypes and assumptions of everyday life (May, 2001; 31).
Therefore theory is required to provide a level of abstraction which detaches the researcher from the subject (30).
It must also be noted, however, that the results of research actually regulate the researcher's own ontological and methodological perspective, as data that challenges the original theory forces the researcher to re-consider their position.
The necessity of a having a view of social reality because social reality itself is not united shall now be explored.
--- Para SEP ---
The debate between Ralph Miliband and Nicos Poulantzas reveals that a clear distinction exists between social structure and individual action.
By debating the importance of either structure or action, these two Marxist writers reveal that having an ontology is necessary as there can be no one unified theory of society, as social reality itself is not unified (Craib, 1997; 269).
Ralph Miliband adopts an Individualist approach to answering the question 'who is the Ruling Class?' in his book The State in Capitalist Society (1969), (which generated the debate with Poulantzas).
Due to his ontology Miliband investigates the specific members of the 'Ruling Class' and how they are connected to each other; he concludes that the 'Ruling Class' is constituted of individuals who share a common cultural background (such as attending the same schools) and the common interest of reproducing the capitalist system (as they benefit from it) (Miliband, 1973; 254-259).
Alternatively, Poulantzas answers the question form a Collectivist perspective.
He emphasises the importance of state institutions that persist regardless of the individual occupying them, and that individuals merely fulfil the 'role requirements' of their position within the capitalist system (Poulantzas, 1973; 242-245).
Although these perspectives were presented as oppositional, I considered the merits of each to be complimentary.
Neither satisfactorily dismissed the evidence of the other, and the possibility that both interpretations of the 'Ruling Class' could be correct (if reconciled) emerged.
Therefore, I was encouraged to believe that there were two distinct strata of the 'Ruling Class', which could not be reduced to each other (and this is one of the central tenets of Realism).
In light of this, the premises of Individualism and Collectivism needed to be evaluated.
--- Para SEP ---
I was dissuaded from adopting the Individualist's perspective because of its inherent contradictions regarding reductionism and the role of the social context.
Individualism's principle that social structures and phenomena must be reduced to statements about the interrelations of individuals (because the individual is the smallest constituent part of society) leaves it susceptible to criticism from psychologists who state that people themselves can be reduced further still into their underlying psychological features (Archer, 1995; 39).
Due to their belief in reductionism it becomes difficult for Individualists to deny the psychologists' claim that society is the reflection of the combined psyches of the population (40).
However, to defend their position from psychologists Individualists invoke the Collectivist notion of emergence.
They claim that their concept of the individual is unique because it is defined by the individual's participation in relationships that pre-date them, for example 'English speakers do require other English speakers to become such themselves' (40).
This recognition of an emergent structure (such as the English language) contradicts Individualism's premise that everything in society is reducible to an individual's dispositions.
The Individualist's response to this criticism is to incorporate all non-individual and non-dispositional factors into their concept of the individual, such as a person's 'physical resources and environment' (Watkins, 1971; 110).
This again reveals a contradiction, as these aspects of social reality are not about individuals or dispositions (the exclusive focus of the Individualist) yet are central to the Individualist's concept of the individual.
Individualism's inability to discredit the Collectivist's concept of social structure provided further impetus not to adopt their view.
--- Para SEP ---
Individualism cannot successfully prove that social structure is not autonomous from, pre-existent to, and does not exert a causal influence over individuals (Archer, 1995; 42).
Individualists claim that social structure is not independent from individuals because the social structure is constituted of interpersonal relations (43).
Collectivists oppose this idea because it does not take into consideration the importance of social roles in determining behaviour; they state that people behave appropriately to the role they are fulfilling (such as the interaction between a solicitor and a client) regardless of the individuals involved (43).
Individual's rebut this criticism by denying the pre-existence of social structure; they claim that features such as 'roles' only exist because the individuals concerned lack the desire or the knowledge to change them (44).
Collectivists disprove this claim by adducing the resistance shown by structures (such as the rate of recruitment into the police force) to the concerted efforts of individuals trying to change them; this proves that structures pre-exist and outlive specific individuals and their attempts to alter them by showing that they possess properties independent of the individual's influence (44).
Additionally, it can be argued that the dispositions which are so important to Individualists are shaped and restricted by their historical context (Gellner, 1971; 100).
Consequently, Individualist's cannot prove that structures do not have a causal influence (such as a low level of recruitment into the police force being causal of a high crime rate in urban areas).
Although Collectivism highlights the inadequacy of Individualism's methodological approach, it does not offer a significant counter-ontology, and is therefore inferior to the Realist approach.
--- Para SEP ---
Realists show that the flaws of Collectivism stem from its inability to transcend Empiricist concepts.
Collectivists were never able to define the exact ontological status of 'societal properties' (as defined by Mendelbaum) (49).
This is because a societal property cannot be empirically proven as it does not have a tangible existence which can be directly detected by an individual's senses (49).
In addition to this, the Empiricist concept of causation (whereby a phenomenon only has causal power if it produces constant conjunctions at an empirical level) denied social structures causal power, because they are neither observable nor causal in their effect (based upon this definition) (52).
Realism solves this problem as it recognises that society is an open system in which events are influenced by other contingencies, so the causal influence of emergent properties is not to consistently produce observable effects (53).
Therefore, Collectivism could only challenge Individualism methodologically (by showing that some features of society cannot be reduced to statements about individuals) but could not advance a counter-ontology (because of the dominance of Empiricism) stating the existence of non-observable properties (54).
Realism, however, does not recognise the validity of the Empiricist notion that all things which are held to exist must be detected through human sensory experience.
The basic tenet of Realism is that society is stratified into individuals and the emergent, non-observable, social structure, and that these two non-reducible strata interact and influence each other (61).The differences in perspective between Structuration Theory and Realism clarifies the justification for my decision to adopt a Realist view of social reality.
--- Para SEP ---
Both Structuration Theory and Realism re-conceptualized the relationship between structure and action.
Structuration Theory endeavours to transcend the dualism of structure versus action by depicting them as inseparable, whereby structures are produced by social action, yet social action is only possible because of the existence of social structures (such as the use of language, which allows individuals to express themselves, but only exists because individuals use it correctly) (Taylor, 1995; 688).
Regardless of their claim to have transcended the structure versus action dualism, it can be argued that Structuration theorists actually give primacy to the role of social action, and merely reduce structure to being a property of action (Craib, 1997; 268).
Therefore, Structuration Theory does not offer an adequate alternative to Individualism and Collectivism as all three are ontologically preoccupied with either reducing structure to action or action to structure.
Realism manages to overcome the structure versus action dualism by recognising that neither structure nor action is a completely dependent feature (Archer, 1995; 61).
Realists maintain that social reality consists of both structures and actors; although the existence of structures is dependent upon the actions of individuals, once they have emerged they possess their own properties and powers which can then have an effect upon the actors, therefore the proper object of sociology should be investigating the interplay between these two strata (63).
--- Para SEP ---
In this essay it has been described why a sociologist must have a view about the nature of social reality.
It was also discussed how the different manifestations of the 'Ruling Class' are representative of the stratified nature of social reality.
The different methodologies and ontologies of Individualism and Collectivism were compared to show how Collectivism exposes Individualism's methodological flaws.
However, it was then shown that that the ontological premise of Collectivism is not far reaching enough to persuade me to adopt its view of social reality.
Finally, Realism was depicted as providing the ontological depth that the Collectivist approach lacks, in addition to its superiority over any other theory that also rejects (or purports to reject) the structure versus action dualism.
--- Para SEP ---
It therefore follows from the evidence presented here that I adopted a Realist view of social reality because of the insufficient level of importance and autonomy assigned to either action or structure by other perspectives.
Individualism cannot successfully deny the importance of an autonomous, activity causal social structure, whilst Collectivism cannot disprove Individualism's ontological foundations because of its own Empiricist nature.
Similarly, Structuration Theory does not transcend the structure versus action dualism, but merely reinvents the terms of the debate in another terminology.
Consequently, Realism offers the most comprehensive perspective of social reality because it takes the existence of both individual action and an autonomous social structure as its central tenet, and avoids the ontological and methodological contradictions of the approaches that define these features as inseparable.
--- Para SEP ---
''',
'''This essay investigates the different types of stem cells, their origins and properties and why these characteristics have generated so much hope that stem cells can offer solutions to numerous different diseases and medical conditions.
--- Para SEP ---
Stem cells are a unique population of cells found in both adult and foetal tissues which have the ability to renew themselves, to remain undifferentiated and to respond to specific signals and conditions, triggering differentiation.
Within adult tissues (such as bone marrow, the brain and muscle), stem cells act to replace cells lost naturally, by disease or through injury.
As such, adult stem cells are multipotent and can renew their own population and differentiate to yield the specific cells of their originating tissue.
An example of this is shown in Figure 1 where haematopoietic stem cells (HSC) found in the bone marrow may divide symmetrically to regenerate their own population, or asymmetrically forming a further HSC and a daughter cell, the latter of which is committed to one of the two major haematopoietic lineages and hence replenishes the body with all the different blood cells (1).
--- Para SEP ---
In contrast to adult stem cells, those obtained from embryos are pluripotent and have no fixed developmental process.
The fact that pluripotent stem cells can theoretically differentiate into any cell type in the body has generated much research into developing methods to use pluripotent stem cells for cell-based therapy, and hence repairing tissues damaged by disease or injury.
--- Para SEP ---
Pluripotent stem cells i.e. distinct cells with complete developmental plasticity can be found in three different sources; embyronal carcinoma (EC) cells, embryonic stem (ES) cells and embryonic germ (EG) cells.
The ability of stem cells to differentiate into such a wide variety of different cells was first recognised in testicular cancers.
It was noticed that weird tumours formed that contained a wide variety of different tissue types, for example squamous epithelium and muscle, all of which were derived from pluripotent EC cells which themselves were derived from the primordial germ cells (2).
The extent of tissue differentiation in this finding was examined using artificially cultured EC cell lines derived from the tumours, in the presence and absence of a mitotically inactive layer of fibroblasts, the feeder layer (Kahan et al.
referenced in 2).
--- Para SEP ---
The second category of pluripotent cells ES cells, are derived from the three to five day old embryo known as the blastocyst which consists of a hallow microscopic ball of around 150 cells (3).
This pre-implantation embryo contains around 30 pluripotent cells in its centre known as the inner cell mass (ICM) which, as demonstrated by outgrowth cultures, can differentiate to yield many different specific cell types.
During the outgrowth of ES cells, it was noted that some of the cells remained undifferentiated and if sustained on a feeder layer to which they could adhere and obtain nutrients from, they could be expanded to produce a seemingly immortal ES line (2).
--- Para SEP ---
Finally, EG cells are derived from the primordial germ cells (PGC), the embryonic precursors of gametes and the same cells from which EC cells derive (4).
This final group of cells were identified as having stem cell properties after growth upon feeder layers supplemented with serum and growth factors produced clusters of colonies that were morphologically indistinguishable from EC or ES grown under the same conditions (2).
--- Para SEP ---
In recent years the potential uses of stem cells in medicine have gained increased appreciation and as a result have driven the need to understand the factors regulating and controlling stem cells in their natural environment.
However, the challenge of producing different types of differentiated cells from pluripotent stem cells first needed to be overcome.
Many investigations focussed on changing growth conditions, for example cell density or adding specific growth factors, but as such changes were dictated by trial and error the cellular differentiation achieved in this way was extremely haphazard and varied (2).
In contrast, other studies where ES were grown in a development culture demonstrated that the cells began to differentiate into multicellular aggregates called embryoid bodies- clusters of cells that due to the variety of tissues formed represent early embryos (1,2,5).
If these embryoid bodies were then transferred to a solid medium they developed into many different cell types for example neural cells and cardiomyocytes which could be separated for further study by methods such as fluorescence activated cells sorting (FACS) (6).
However, the generation of embryoid bodies in this way could not be used in a controlled manner to produce specific cell types as it was due to spontaneous differentiation (5).
As a result other molecular methods such as those shown in Figure 2 have been used to determine protocols for directed differentiation of ES cells into certain cell types.
--- Para SEP ---
If the differentiation of ES can be developed reliably as suggested in Figure 2, then stem cells have the potential to become an important tool in treating some of the major diseases such as diabetes and traumatic spinal chord injury.
However at the present time this ability is only available to a very limited number of cell types.
--- Para SEP ---
The use of stem cells in medicine is not only relevant for curing diseases such as diabetes and muscular dystrophy, but also in gaining an increased understanding into the development of our own species.
By using ES cells to understand why developmental points such as cell formation and proliferation occur and how these process impact upon embryogenesis, we can gain an increased understanding as to why conditions such as teratogens (which cause foetal malformations) are generated, and in addition possibly develop new pre-natal screens to detect such conditions (7).
--- Para SEP ---
However, the main potential of pluripotent stem cells lies in the development of patient-specific tissues for transplantation and restoration of damaged or diseased tissues.
This process of therapeutic cloning would involve taking samples of the patients ES cells and manipulating them to differentiate into the large numbers of cells needed to cure disease or restore tissue function.
Figure 3 gives an outline of the range of conditions ES could be used to treat.
--- Para SEP ---
Many success stories have been documented (8) however a major factor holding back the development of such techniques in many countries (for example the United States of America), are the ethical issues surrounding the cloning of embryos for use in stem cell research.
As such, research is also being undertaken to investigate the potential for adult stem cells in medicine.
--- Para SEP ---
In comparison to embryo-obtained pluripotent stem cells, which are obtained from the PGC, multipotent stem cells from adults, are derived from soma i.e. cells which are no longer capable of making germ cells due to developmental totipotency (2).
Because of this it was thought that adult stem cells had only very small differentiation ability.
--- Para SEP ---
However in contrast to this belief, a plethora of research such as that carried out by Ferrari et al.
(referenced in 9) showed that cells derived from adult bone marrow recent could differentiate into muscle cells i.e. differentiate into cells that were from a completely different tissue to the one from which they were isolated (9).
In addition to this work, other studies such as that conducted by Frisen et al.
(10) found that adult stem cells could even cross from one classic germ layer to another for example as CNS stem cells were shown to behave like ES cells when introduced to blastocytes, hence forming cells of all three primary germ layers.
--- Para SEP ---
Although it is unlikely that adult stem cells will ever be able to produce the same range of differentiated cells types as pluripotent embryo-derived stem cells, with such findings of adult stem cell differentiation becoming more frequently documented, further research is needed to establish how adult stem cells could be used grow specific cell types to treat some human diseases and potentially relieve the need to use politically sensitive ES cells.
--- Para SEP ---
Although there has been great insight into the potential use of stem cells in medicine, there still remain a large number of issues which need to be overcome before the theory of cell-based therapies can be made a reality.
Primarily stem cells would be needed in large quantities and their differentiation would need to be controlled in order to form a homologous population of cells (2).
At present the controlled generation of specific cell types differentiated from stem cells has only been documented in a limited amount of cases and therefore the lack of knowledge in this area represents a real challenge before the full potential of cell-based therapy can be realised.
In addition, at present there are only a limited number of human pluripotent stem cell lines and only a few of these have been successfully accredited.
It is likely however that of those accredited an even smaller number will actually prove to be useful in clinical practices and many of those may be unavailable due to patents and material transfer agreements (2).
The long-term survival of some cultured stem cell lines is also a worry as those cells which survive may do so as a result of gene mutations or chromosome abnormalities (2).
--- Para SEP ---
One of the major safety issues is the generation of histocompatible tissues for transplantation.
With such a huge genetic diversity within the human population the problem of tissue rejection must be discussed.
Two solutions to this problem would be to either suppress the immune system of the patient or induce tolerance.
However, these solutions are only short-term and the ideal situation would be to make pluripotent cells from embryos that would be compatible with any individual (2).
This could be achieved in two ways.
Firstly, samples of nuclei taken from the patient's soma could be used to reprogram the cytoplasm of an oocyte, such that when the embryo develops it produces stem cells that are genetically identical to the patient i.e. therapeutic cloning.
Secondly, homologous recombination could be carried out in existing stem cells to create a line which is compatible with the patient.
Both of these techniques however are difficult to conduct and therefore at present the problem of histocompatibility remains.
--- Para SEP ---
A second safety issue is the improper differentiation of implanted cells or development of tumours after transplantation.
This concern has come from research such as that carried out by Tada et al.
in which EG cells were used to study the changed in epigenetic modifications in the germ line by analysing the effects on a somatic nucleus (11).
Analysis found that the presence of EG cells caused 'striking changes in methylation of the somatic nucleus, resulting in demethylation of several imprinted and non-imprinted genes' (11).
Such modifications were shown to be heritable and affected gene expression (11).
This and other findings of a similar nature therefore reinforces the idea that differentiated cells rather than stem cells may be more suited to transplantation.
--- Para SEP ---
The final issue surrounding the use of stem cells in medicine is the worry that patients may acquire infectious agents from infected embryo-derived pluripotent stem cells or the bovine serum feeder layers required for growth (2).
As a result, work has been carried out to develop murine ES cells that do not require feeder cells for growth and human ES cells which require either foetal calf serum or conditioned medium processed by mouse feeder cells (Nichols et al.
and Xu et al.
respectively as referenced in 2).
However in order to eliminate the concern of infectious agents in stem-cell derived transplantation materials, a serum-free medium with purified recombinant growth factors on a defined extracellular matrix will need to be developed.
--- Para SEP ---
Diabetes is a condition characterised by abnormally high levels of glucose in the bloodstream which reduces life expectancy by a median of twelve years (Mangel et al.
referenced in 13) and affects sixteen million people in the USA (12).
The development of this disease can be classified as either type one or type two (1).
Type one diabetes, or juvenile-onset diabetes, is an autoimmune condition in which self-pancreatic cells are targeted by immune cells and are destroyed.
As a result the islets of the pancreas are unable to secrete insulin in the presence of glucose.
Type two diabetes is generally associated with older, overweight individuals and develops when the body cannot use insulin effectively (1).
In both cases the result of this disease causes excessive glucose accumulation in the blood which can lead to further complications such as blindness and heart failure.
--- Para SEP ---
At present the well-established treatment for diabetes, the use of exogenous insulin, is very effective and safe for self-treatment by patients (12).
However the side effects of this treatment are not well understood and although the Diabetes Control and Complications Trial Research Group (referenced in 13) have shown that intensive treatment in this way controls hyperglycaemia and reduces long-term complications, there is still room for improvement.
--- Para SEP ---
The childhood onset of type 1 diabetes predisposes the patient to complicated secondary conditions and therefore this population would certainly benefit from alternative treatment.
In addition, intensive insulin therapy treatment doesn't achieve the normal haemoglobin A1c levels which is important in the generation of diabetic organ damage and therefore this problem could be combated using stem cell therapy.
As a result, if stem cells were to be used in the treatment of diabetes, they would have to compete against the well-established exogenous insulin treatment and be able to offer significant advantages over this system before the risks associated with transplantation could be justified (13).
--- Para SEP ---
At present two milestones have been achieved in the development of ES for treating diabetes.
Firstly ES cells have been directed to differentiate to form insulin-producing cells in vitro (13).
McKay et al.
(12) first demonstrated this showing that mouse ES cells self-assembled into structures that both physically and functionally resembled normal pancreatic islets.
These engineered cells could even secrete insulin when triggered with glucose in a mechanism similar to that seen in vivo (12).
The protocol used to differentiate such cells was based upon an already established method for producing neurons from ES and is outlined in Figure 4.
--- Para SEP ---
Tests carried out by Csernus et al.
(referenced in 13) measured the level of glucose-dependant insulin release in the engineered cells.
They found that at the end of stage five (as shown in Figure 4) the cells released insulin in a 'dose-dependant manner with fast kinetics characteristic of primary pancreatic islets in vitro'.
However, it was calculated that the cultured cells contained fifty times less insulin than normal islet cells, a figure which is likely to increase with further research.
The mechanism of insulin secretion was also investigated by detecting the effects of several agonists (e.g. tolbutamide, a sulfonylurea inhibitor of ATP-dependant K+ channels) and several antagonists (e.g. diazoxide, an activator of ATP-dependant K+ channels).
It was found that similarly to in vivo, the agonists all stimulated the secretion of insulin whilst the antagonists inhibited insulin secretion.
This therefore suggested that the insulin-positive cells generated from ES cells used normal pancreatic machinery to secrete insulin (12).
--- Para SEP ---
The second milestone was demonstrated by McKay et al.
and showed that engineered insulin-producing cells have transplantation ability (12).
When injected into diabetic mice the cells rapidly self-assembled by vascularizing and maintaining a clustered, islet-like organisation.
This is shown in Figure 5.
--- Para SEP ---
The experiments by McKay et al.
were unable to demonstrate that the engineered insulin-secreting cells could overcome hyperglycaemia in diabetic mice, however this was not unexpected as it was known through previous investigations that the engineered cells could not produce as much insulin as native pancreatic islets (12).
--- Para SEP ---
It is clear that engineering ES cells in this way holds great prospects for generating immunocompatible tissues for transplantation in the treatment and potential cure of diabetes.
It needs to be remembered however, that although the research into this area is moving forwards the clinical approach to compete with exogenous insulin use is still a long way off.
--- Para SEP ---
The process of tissue engineering refers to the production of spare parts to replace damages or lost organs using postnatal stem cells.
The skin is a well-understood organ and as such there has been much research into the ability of stem cells to generate skin grafts for patient-specific transplantation.
The precursor skin cells are ranked into a hierarchy and under clonogenic conditions form three different types of cell types, holoclones, meroclones and paraclones (15).
Of these three lines only holoclones have the ability to self-renewal and therefore are the only product of a true stem cell.
Because of this, a small pure population of holoclones could be used to generate an epidermal graft (15).
The production of skin autographs in vitro is described in Figure 6.
--- Para SEP ---
The results of such experimentation have been varied.
It was found that if the experimental conditions were not correctly set, the holoclone-generating compartments in the cell cultures became depleted in a manner similar to when part of the epidermal stem cell compartment becomes depleted during ageing.
Secondly, graft failure was also noted (15).
As a result, this study demonstrated that the experimental design and potential uses of using stem cells in tissue engineering are present, but putting them into practice is a long way off.
Currently only a very small number of areas have seen the theory translated into clinical practice.
--- Para SEP ---
The use of mouse ES cells during the past twenty years has revolutionized our understanding of embryonic, foetal and postnatal development in mammals.
The availability of human pluripotent stem cells has now opened up many exciting possibilities for the future.
In the next few years, new molecular advances may aid the identification of critical genes involved in stem cell differentiation and renewal, whilst others may develop methods to manipulate stem cells in vivo.
--- Para SEP ---
Although there have been many success stories of different cell lines that have been developed from pluripotent cells and transplanted into animal models, we may find that there are some cell types which are impossible to develop, whilst others may not be suited for human transplantation.
With so many unanswered questions and endless possible uses for stem cells in medicine, it is without doubt that stem cell research will remain highly active for many years to come and in doing so will hopefully provide many answers for diseases such as diabetes and muscular dystrophy which affect thousands of people throughout the world every day.
--- Para SEP ---
''',
'''Frozen desserts include ice cream, frozen yoghurts, ice milk, sherbet and ices (Arbuckle, 1972).
Of these, ice cream is considered to be the most commercially important in the frozen desserts category (Varnham & Sutherland, 1994).
--- Para SEP ---
Within the UK, ice cream is defined as a frozen product containing a minimum of 5% fat and 2.5% cent milk protein.
This is achieved by subjecting an emulsion of fat, milk solids and sugar or sweeteners, with or without extra ingredients, to heat treatment and then freezing (Regulations, 1996).
--- Para SEP ---
An emulsion is a system of droplets that are suspended in a continuous immiscible phase and are separated by an interfacial layer which is occupied by a surfactant material which contain proteins (Friberg et al., 2004).
--- Para SEP ---
Ice cream is a colloidal system; small particles of one phase are dispersed into a continuous phase.
Ice cream is an emulsion (fat), a sol (sugars, polysaccharides / stabilizers, milk proteins and ice crystals) and a foam (air), often with 50% air, referred to as over run.
It is a microstructure which consists of fat droplets, ice crystals and air bubbles suspended in a viscous solution which makes up the matrix (Clarke, 2004).
--- Para SEP ---
Milk contains approximately 3.5% protein, that fall into two categories, caseins and whey proteins, based on their precipitation at pH 4.6 at a temperature >8ºC.
80% of the total nitrogen precipitates as casein and 20% remains in the whey, with 15% of the nitrogen as whey protein and 5% as non-protein compounds (Fox, 1992).
Caseins are more heat stable than whey proteins.
Caseins are stable at 140ºC but whey proteins denature at >70 ºC (Fox, 1992).
--- Para SEP ---
The use of milk proteins as food ingredients depends on their physicochemical nature and their functional properties.
Their amphiphilic nature causes them to concentrate at interfaces.
Sodium caseinate is more effective at reducing interfacial tension than whey protein.
It diffuses to an interface more rapidly and absorbs more quickly than other proteins.
Generally, caseinates produce higher volume but less stable foams than whey protein concentrates.
Protein concentration, the level of denaturation, ionic environment, preheat treatments and the presence of lipids are all factors affecting this.
The effectiveness of whey protein as a surfactant is enhanced by partial heat denaturation (Fox, 1992).
--- Para SEP ---
The main functionality of both whey protein concentrates in ice cream systems are gelation, viscosity, heat stability, acid stability, nutrition, emulsification, aeration and film formation.
Individual proteins have intrinsic factors which are their principle functions.
The principal whey proteins are β-lactoglobulin, α-lactalbumin, immunoglobulins and bovine serum albumins (BSA).
Emulsification is the intrinsic factor for α-lactalbumin and bovine serum albumins (BSA).
Useful concentrate ingredients will enhance and develop intrinsic factors making them ideal for food processors (Huffman, 1998).
--- Para SEP ---
Using whey protein to replace milk proteins results in a decrease in the amount of de-emulsified fat.
A softer and wetter product is made resulting in faster melting properties.
Whey protein has stronger emulsifying properties than milk protein and so whey protein desorption from the interface by monoglyceride is less effective in comparison to milk protein.
The increased emulsion stability by whey proteins may be counteracted by more effective de-emulsification which is achieved by increasing monoglyceride concentration (Whitehurst, 2004).
--- Para SEP ---
Altering the pH of the whey has a large effect on emulsification as it changes the state of the protein aggregates and the size of the protein.
A similar effect can be achieved by heat (Huffman, 1998).
--- Para SEP ---
During oil-in-water emulsification, new surface area is generated by the break down of fat globules into smaller droplets.
New droplets can only be made permanent and stabilized against coalescence by the adsorption of emulsifier molecules at the oil-water interface.
This is most efficient if the adsorption occurs rapidly.
The type of emulsion depends on the type of emulsifier used (Whitehurst, 2004).
--- Para SEP ---
Emulsifiers are amphiphilic systems and so contain both hydrophilic and hydrophobic parts.
They concentrate and orientate themselves between the fat globules and the aqueous phase reducing the interfacial tension in the immiscible system.
Adsorption of emulsifiers is more energetically favourable than complete absorption in either the aqueous phase or fat globule.
As the interfacial tension produced by the emulsifier decreases, the fat increasingly becomes destabilised (Marshall & Arbuckle, 1996).
--- Para SEP ---
Egg yolk, which contains phospholipids as the emulsifier was the first emulsifying agent used in ice cream.
However it is expensive and may produce off flavours (Hyde & Rothwell, 1973).
Most commercial lecithins are now by-products of vegetable oil refining.
Egg lecithin is extracted using ethanol and acetone.
This combined extraction is expensive but lecithin is widely used for its emulsifying properties.
Hydrolysed lecithins show a higher surface activity as hydrolysis of the phospholipids makes them more hydrophilic by losing a fatty acid and because the polar group gains more weight in the molecular structure (Whitehurst, 2004).
--- Para SEP ---
The majority of the world's production of emulsifiers is mono- and diglycerides, originally produced as alternatives to lecithins.
They are produced by interesterification of triglycerides with glycerol by a reaction at >200ºC under alkaline catalyst.
The glyceryl portion is hydrophilic and the fatty portion is hydrophobic.
They are insoluble in water but can form stable hydrated dispersions (Stauffer, 2005).
--- Para SEP ---
Monoglycerides compete with proteins at the fat-water interface and at the air-water interface.
Less saturated fatty acid monoglycerides are more active at the interface.
The air-water interface is stabilized by denatured milk proteins, partially destabilized fat and agglomerated fat globules.
Monoglycerides are mainly responsible for partial destabilization of the fat emulsion.
They first decrease the oil-water interfacial tension, more so than milk proteins then promote desorption of milk protein from the interface.
The interfacial layer has reduced strength or elasticity (Whitehurst, 2004).
--- Para SEP ---
The fatty acid composition of monoglycerides reflects the make up of the triglyceride from which it came.
Unsaturated monoglycerides consist of a mixture of oleic, linoleic and the trans form of these acids.
Hydrogenated monoglycerides have a higher melting point than unsaturated.
The phase diagrams for highly unsaturated and saturated monoglycerides are significantly different.
Depending on temperature and water concentration, monoglycerides take on different forms in the mesophase.
Behaviour in the mesophase governs monoglyceride functionality.
When heated to their melting point, they produce a gel (Stauffer, 2005).
--- Para SEP ---
Emulsifiers exhibit temperature dependent behaviour, which is demonstrated in aqueous solutions.
Monoglycerides have similar phase behaviour to triglycerides in their bulk phase and exist as either an alpha structure or a beta structure, the difference being the arrangement of molecules in the crystal structure.
When cooled from a molten state an alpha prime metastable crystalline structure is formed.
Further cooling results in the formation of a stable beta state, which forms if the alpha prime state is stored at ambient temperatures.
In an aqueous phase, the beta crystal interacts with water to form a lamellar liquid crystal which cools to form an alpha gel phase.
When cooled from melt monoglycerides, similarly to triglycerides, often form an unstable alpha type crystal, then transform to the beta prime form before settling in the stable beta form (Euston, 1997).
For some applications, the alpha form is most advantageous because of easier dispersibility, improved aeration properties and increased emulsification properties (Whitehurst, 2004).
--- Para SEP ---
Distilled monoglycerides, which have been separated from the di- and triglycerides and glycerol, show better dispersibility in water than mono- and diglycerides due to having a former liquid crystalline mesomorphic phase, whereas monoglycerides (not distilled) form emulsions due to a relatively high content of triglycerides (Whitehurst, 2004).
--- Para SEP ---
Monoglycerides also have the ability to influence fat crystallization.
Glycerol monostearate initiates more fat crystallization than glycerol monooleate but does not displace as much protein.
Monoglycerides such as these, act as nucleation points for surface crystallization of triglycerides (Euston, 1997).
--- Para SEP ---
Other developments such as polyoxyethelene sorbitan monostearate or monooleate are very powerful and so only a small amount is needed, too much of these will cause the fat globules to churn (Hyde & Rothwell, 1973).
--- Para SEP ---
The dispersion of fat globules in ice cream mix depends on forces which tend to pull fat globules apart - the homogenizer valve and repulsion between fat globules due to their electrical charges.
Freezing can affect the stability of fat globules in ice cream.
The globules agglomerate due to agitation and the concentration effect of freezing.
The rate of this agglomeration may also be affected by protein stability, melting point of the fat, types of emulsifier, stabilizer and sugars and the salt content (Marshall & Arbuckle, 1996).
--- Para SEP ---
Dryness is related to emulsion instability.
This is due to agglomeration of milk fat globules which slows down the rate of melt down.
Agglomeration may therefore be desirable.
However, if agglomeration goes too far, it may cause churning.
Negative charges of the fat globules, which cause them to repel each other, are lost or overcome by agitation.
An ideal mix is one where all the fat is agglomerated but in which none visibly churns out.
In this condition, ice cream possesses optimal textural properties, body, dryness and stiffness.
Certain emulsifiers tend to destabilize the fat which can accelerate churning.
Excessive destabilization results in a slow melt down but the ice cream retains its shape or structure (Marshall & Arbuckle, 1996).
--- Para SEP ---
The use of whey protein as a replacement for other milk proteins is common but as the amount of whey protein increases, the amount of de-emulsified fat decreases which results in a softer and wetter ice cream.
The desorption of whey protein by monoglycerides is less effective in comparison to caseins.
The increased emulsion stability exhibited by whey proteins can be counteracted by either increasing the monoglyceride concentration or by applying more effective unsaturated monoglycerides (Whitehurst, 2004).
--- Para SEP ---
The proposed investigation will take the following form.
--- Para SEP ---
Obtaining different monoglyceride emulsifiers, predominantly monostearate monooleate, and monolinoleate, based on their level of saturation.
--- Para SEP ---
Preparation of ice cream mixes and products using each of the different types of emulsifiers.
The ice cream will have a low pH. This will be achieved by the addition of fruit based ingredients, which are high in acidity.
The ice cream mixes will be made using a standard method.
The type of protein in the system will be controlled.
Each emulsifier will be tested at a range of protein concentrations.
--- Para SEP ---
The emulsions will be tested for their stability according to the monoglyceride used and the level of protein in the mix.
The following tests will be carried out.
--- Para SEP ---
Measurement of free fat by solvent extraction.
This will provide a measurement of the amount of fat that has been de-emulsified by the emulsifier.
--- Para SEP ---
Analysis of particle size of the fat globules in the mix using the Malvern Particle Size Analyzer.
This will provide information on the different sizes and shapes of the de-emulsified fats in the ice cream samples.
--- Para SEP ---
Measurement of the meltdown properties of the ice cream samples at immediately after freezing and after storage.
This will involve observing changes in the shape, the rate at which the ice cream drips and the weight lost during melting over a period of time.
Consistent volume, over run and dimensions of the sample will be important for this test.
--- Para SEP ---
Measurement of firmness of the ice cream product using a penetrometer.
The test will be performed at immediately after freezing and after the ice cream has been stored to test how its firmness changes over time.
--- Para SEP ---
Assessment of organoleptic properties of the mixes through sensory analysis to evaluate the acceptability of the ice cream textures.
This will complement other tests performed in the investigation.
--- Para SEP ---
''',
'''Since Neolithic times, Man has dramatically altered the landscape of Britain from a former almost blanket forest cover more than 12,000 years ago to a predominantly open landscape today.
The present landscape is made up of a variety of habitats.
As well as woodland, there are also those created by Man, including moorlands (especially on the uplands), heathlands and grasslands.
These are 'plagioclimatic communities', habitats that have been arrested a particular stage of succession, and are maintained under various forms of management pressure such as burning and grazing.
--- Para SEP ---
Grazing comes in many forms.
The major grazing animals of Britain today are cattle, ponies, sheep, deer, and rabbits.
The main effects by herbivores are grazing, trampling, elimination and nutrient input.
Grazers vary in what vegetation they eat and how.
Sheep are able to crop the grass to a very small height (mm) due to their jaw and teeth structure, whereas cattle tear grass with their tongues.
Ponies also crop the grass to a short height but are important in nutrient cycling of an area (Putman et al., 1989).
--- Para SEP ---
In temperate systems, heath, acid grasslands and bogs experience lower grazing pressure during a year than woodlands (especially deciduous).
The latter are used constantly thoughout the year for shelter and feeding.
Various improved grasslands also have a high level of use by herbivores.
Ponies spend half their time on grasslands over a year (Putman, 1986).
--- Para SEP ---
Grazing animals have an immediate influence on the functioning and development of a community by altering the relative abundance of plant species.
Often, palatable plants are eaten at expense of less-favoured coarse species and in time the latter comes to dominate a habitat.
--- Para SEP ---
This report aims to give a brief overview of the effects of grazing pressure on upland moorland, lowland heathland, lowland deciduous forest and grassland habitats of Britain.
The role of grazing in conservation is discussed.
'Browsing' is included in the meaning of 'grazing' in this review.
--- Para SEP ---
Particularly since the Second World War, Britain's uplands have been subjected to intense grazing pressure by sheep, causing great loss of heather moor.
As a consequence, there has been a general decline in biodiversity in the uplands, including Snowdonia National Park, a designated Special Site of Conservation.
--- Para SEP ---
Sheep grazing in upland Wales is not beneficial to wildlife, as they prefer more palatable species and avoid siliceous plants e.g.
Molinia caerulea (Purple Moorgrass) (Rieley & Page, 1990).
M. caerulea and Nardus stricta (Mat-grass) thrive under high grazing pressure and soon become dominant in the community at the expense of more palatable species.
For example, the Nardeto-Caricion bigelowii acid grasslands, which occur <1300m, are dominated by N. stricta.
Their ranges have extended much across the upland regions due to grazing.
--- Para SEP ---
Good et al.
(1990) studied vegetation type in relation to sheep densities in north Wales.
Under increased grazing pressure, bushes have decreased and recruitment prevented.
In order to allow saplings to establish and mature, sheep density must be reduced for a prolonged period of time (e.g.
15 years).
If grazing continues at high levels, conservation problems are likely to occur in the future.
--- Para SEP ---
At Hafod y Llan farm, in the Snowdon National Nature Reserve, Wales, sheep density has increased over the past few decades.
The pressure has led to severe decline in valuable habitats for wildlife such as mires and wet heaths, which support breeding curlews and lapwings.
This is a typical case for many farmlands in Wales.
In such areas, M. caerulea has become the dominant and poses a fire hazard.
Dry heath, which supports red grouse and merlin, has also depleted, leaving non-diverse vegetation dominated by N. stricta.
Regeneration of Quercus (Oak) woods and upland Ulmus (Ash) woods is prevented under high grazing pressure.
--- Para SEP ---
Since the 1980s in England and Wales, the Government took on a new approach to more sustainable farming and has made efforts to remedy the situation by means of agri-environment schemes, such as ESA (Environmetnally Sensitive Areas) and CSS (Countryside Stewardship Scheme).
In Wales, the National Trust and Countryside Council for Wales (CCW) have worked with farmers to conserve/enhance biodiversity and beauty, historically, improve and enhance habitats using the very element that caused the damage in the first place - grazing.
--- Para SEP ---
Certain schemes included the pasture/woodland scheme, designed to create a chain of diverse woodland with open glades and scrub, maintained by light sheep grazing with some cattle.
Welsh Black cattle are used to seasonally graze woodlands to keep down the Molinia.
Improvements were observed to be fast on heather.
--- Para SEP ---
At ADAS Pwllpeiran Experimental Farm, mid-Wales (a consultancy and research centre for land bases industries), low-level grazing was needed to prevent invasion of Sorbus aucuparia (Rowan) and Picea sitchensis (Sitka spruce) to maintain grasslands.
Heath was improved to standard NVC H12 Calluna/Vaccinium community.
--- Para SEP ---
Smallshire et al.
(1997) advised suitably low stocking levels preferably by hardy animals (e.g.
Galloway cattle and Scotch Blackface sheep) along with small-scale planned burns of dwarf shrub.
They suggested for upland heather to be maintained in good condition requires a stocking rate of 0.075-0.225 livestock units (LUs) /ha.
--- Para SEP ---
Heathland has low structural diversity (Putman, 1986).
Heathlands of south Hampshire support much M. caerulea among the Calluna and Erica heaths.
This grass can be deleterious to heathland communities as it can dominate and out-compete Calluna.
--- Para SEP ---
Calluna is easily trampled and shoots are killed by contact with N rich urine.
It is more common on less intensively grazed areas (King, 1960; Hunter, 1962).
Scorching also affects Agrostis setacea (Bristle bent grass) and Erica species.
Enrichment of the soil by excreta promotes growth of Carex panicea (Carnation Sedge), M. caerulea and A. tenuis (Common Bent) (Putman, 1986).
--- Para SEP ---
Grazing may modify lichen distribution (Farrell, 1993), such as on the Breckland heaths.
Sheep tend to congregate in certain areas and disturb lichen cover, and create bare patches of ground into which annual plant species such as Erophila verna (Common Whitlowgrass), Teesdalia nudicaulis (Shepherd's Cress) and Saxifraga tridactylites (Rue-leaved Saxifrage) can spread at the expense of other heathland vegetation.
--- Para SEP ---
Trampling and dunging may cause significant damage to important reptile areas in heathland.
It is essential that animals used in grazing regimes on heathland are kept away from reptile foci, particularly those of the rare Sand Lizard (English Nature, 1999).
--- Para SEP ---
Over the last half-century or so, there has been dramatic decline in heathland across Europe; over 85% of British lowland heath has been lost (The Herpetological Conservation Trust, undated).
Contributing to the decline is greatly reduced stock grazing (sheep, cattle and pony).
The most important remaining heaths are in Dorset, Hampshire, Surrey and West Sussex.
Lowland dry heathland supports many important fauna, often species with Biodiversity Action Plans, including various reptiles (e.g.
Sand Lizard and Smooth Snake), birds and arthropods.
--- Para SEP ---
M. caerulea can encroach on heathland and outcompete C. vulgaris, and is a problem in many upland moorlands of Britain.
Milligan et al.
(2004) suggested an Integrated Land Management Strategy for restoring moorland vegetation in upland Britain and keeping M. caerulea controlled.
For restoring moorland, the Strategy advised cutting vegetation three times a year and employing a grazing regime equivalent to ESA levels at ~1.8 ewes ha -1.
Grazing also lowers M. caerulea cover in bog valleys and other heathlands.
--- Para SEP ---
It's probable the New Forest has sustained heavy grazing pressure for most of 900 years, mainly from deer, ponies and cattle.
Grazing has led to a lack of virtually any ground flora/shrub layer in New Forest woodland (Putman, 1986).
There is complete loss of structural layer between 5-20 cm height, and a clear browse line at 200 cm (marks limit where browsing deer can reach).
--- Para SEP ---
Putman et al.
(1989) investigated changes in vegetation and fauna under heavy grazing pressure in an area of woodland in the New Forest.
--- Para SEP ---
They found under grazing pressure, very little tree regeneration takes place and unpalatable species are favoured, maintaining open spaces.
The ground-flora has poor diversity, with palatable species absent e.g.
Mercurialis perennis (Dog's Mercury) and Galeobdolon luteum (Yellow Archangel).
Brambles, ivy and other species are also completely eliminated.
--- Para SEP ---
The herbaceous layer is sparse, dominatd by Oxalis acetosella (Wood-sorrel) and Euphorbia amygolanoides (Wood Spurge).
Palatable shrubby species e.g.
Corylus avallana (Hazel), Prunus spinosa (Blackthorn) and Cretaegus monogyna (Hawthorn) are eliminated and prevented from regenerating.
--- Para SEP ---
There is virtual eradication of many shrub layer species e.g., Acer campestre (Field Maple), Salix caprea (Goat Willow), S. cinerea (Grey Willow), Rubus fruticosus agg.
(Bramble), Rosa arvensis (Field Rose) and R. canina (Dog Rose).
Ilex aquifolium (Holly) and Ulex (Gorse) are severely stunted and 'hedged'.
Pteridium aquilinum (Bracken) gives some structure to the shrub layer (formed the bulk of 10-70 cm height), as it is largely unpalatable to herbivores.
--- Para SEP ---
An ungrazed area has more structural diversity than an area grazed, due to plants regenerating at the ground floor, herbaceous and shrub layers and canopy.
--- Para SEP ---
Under high grazing pressure, particularly palatable or grazing-intolerant species are lost.
Species resistant to grazing (physical/chemical defences) or graze-tolerant (growth-form and physiology able to withstand a degree of defoliation) are encouraged.
--- Para SEP ---
Although continuous grazing prevents secondary succession, there is no significant effect on the population age structure of the forest trees (Putman et al., 1989).
Intensity of grazing varies over years.
At times of relatively low herbivore density some regeneration may occur, enough to guarantee continuation of woodland cover.
Vera (2002) claims livestock grazing leads to development of groves, not that forest disappears as a result.
However, unrelenting use of woodlands with no regeneration leads to development of grasslands.
--- Para SEP ---
As grazing affects the vegetation structure of woodland, this has effects on related ecological functioning such as faunal niches.
Reduced structural diversity under grazing, means less cover and limited food for herbivorous and insectivorous mammals (Putman, 1986).
Diversity of rodents within the woodlands, heathlands and grasslands of the New Forest is much smaller than equivalent areas outside (Putman et al., 1989).
Tawny owls highly predate on wood mice - become specialised, as voles inavailable in the forest.
Buzzards rely heavily on small rodents as prey, and success of breeding is directly related to abundance of prey in an area (Tubbs, 1974).
Low breeding success with high grazing suggests high grazing causes decline in rodents and lower buzzard breeding.
--- Para SEP ---
Grassland species structure and composition is also largely influenced by activities of herbivores.
Plants often grazed grow as a short prostrate canopy under intensive grazing pressure.
This is grazing avoidance behaviour.
In this way, less biomass is 'apparent' and thus more resistant to grazing.
This strategy increases the amount of photosynthesis and meristematic tissue that remains available for regrowth following defoliation (Dawson et al., 2000).
--- Para SEP ---
Extensive lawns are a characteristic feature of the New Forest.
The ponies are responsible for the close-cropped turf, to a height of no more than a few mm.
The lawns lack the structural complexity of mature grasslands.
--- Para SEP ---
However, ponies establish traditional latrine areas (Putman, 1986).
No grazing occurs in the immediate vicinity of fresh dung.
A mosaic of short-grass areas where ponies graze and relatively ungrazed but nutrient-rich latrine areas is created.
In this way, the grazing behaviour of ponies leads to an increase in diversity of the sward itself, promoting a heterogenous community.
--- Para SEP ---
Grazing can alter nutrient cycling and species composition of grassland.
Cattle do not crop herbage as close as ponies, and so are forced to graze in ponies' latrines.
Their dung therefore accumulates also in these areas (Putman, 1986).
This results in patches of high nutrient input and low grazing and patches of continual loss of nutrients and high grazing.
Over time, nutrients are continually transferred from areas grazed by ponies to latrine patches.
--- Para SEP ---
Each sub-community has its own species composition:
--- Para SEP ---
K and P concentrations are higher in latrine areas, and is a major factor to differences in species composition between the sub-communities.
Excretion also increases N content in patches of soil.
Altered nutrient concentrations causes soil heterogeneity.
--- Para SEP ---
Partial shoot defoliation may cause more release of organic compounds from roots especially lower molecular weight soluble exudates (Hamlen et al.,1972).
Improved grasslands typically support more grasses than unimproved, as grazers increase soil nutrient availability by their excreta (Dawson et al., 2000).
This favours bacterial growth in the soil.
However, urine may scorch sensitive plant species.
--- Para SEP ---
Grassland is maintained by specialist grass-eaters e.g. cattle, horses, sheep.
Rabbits are also important grazers.
Herbivores scrape up soil, and rooting of pigs, assisting seed germination of thorny shrubs including Juniperus (Juniper), Rosa, Rubus and Ulex (Vera, 2002).
--- Para SEP ---
Thorny species may be vulnerable to grazing e.g.
P. spinosa, C. monogyna and Rosa.
Annual shoots are not spiny and are readily browsed by cows and sheep.
However, these shrubs may not be totally eradicated from grassland if they can regenerate in under-grazed areas.
Only P. spinosa advances rapidly in low or absent grazing by clonal spreading with runners.
Development of scrub and groves is more a result of initial establishment of trees/shrubs after grazing has ended (Vera, 2002).
--- Para SEP ---
Grasses are generally graze-tolerant and abundant in grasslands.
Active shoot meristems and leaf growth zones are not damaged when a plant is grazed or mown as they are normally situated at the base of the leaf, enclosed by sheaths of older leaves (Schnyder et al., 2000).
Grass roots often form arbuscular mycorrhizae (Newman & Reddell, 1987).
External hyphae network may help compensate for loss of root mass due to defoliation, e.g.
Lolium perenne (Perennial Rye-grass) (Allsopp, 1998).
--- Para SEP ---
With defoliation, root mass, length and rate of elongation decrease (Holland & Dathing, 1990).
Increased dead root material is a resource for decomposer organisms in the soil and could change microorganism community structure and act as subsequent source of nutrients for plant growth (Dawson et al., 2000).
--- Para SEP ---
Grazing affects the pattern of vegetation production.
Low levels stimulate regeneration and higher productivity, and higher levels suppress growth by lowering effective photosynthetic area.
The New Forest grasslands sustain very high levels of grazing pressure, which have significant effects on productivity.
--- Para SEP ---
Grant et al.
(1996a) found floristic diversity of Molinia grassland was greater on grazed ground compared to ungrazed.
Other broad-leaved grass species took advantage as Molinia was grazed and trampling caused higher frequency of bare ground.
In Scotland Nardus grasslands, cattle and goats used N. stricta more than sheep.
Under cattle grazing Nardus cover decreases, whereas sheep grazing increases both the cover and biomass of individual Nardus tussocks (Grant, 1996b).
--- Para SEP ---
On a species-poor grassland in Oxfordshire, Bullock et al.
(1994) found dicotyledonous plant species increased under increased sheep grazing pressure due to their high seed production and increase in gaps frequencies by trampling.
--- Para SEP ---
On chalk grasslands, Brachypodium pinnatum (Tor-grass) and C. acaulon (Dwarf Thistle) are invasive, unpalatable species, which increase under heavy grazing pressure (Rieley & Page, 1990).
After myxomatosis, when the rabbit population decreased in the early 1960s, lower grazing pressure allowed succession towards tall grassland and scrub.
Goats have been used, even at the present day, to control Q. ilex (Holm Oak) on chalk rasslands (National Trust) (Countryfile, 2005), although numbers are managed to prevent erosion.
--- Para SEP ---
We have seen grazing can have a detrimental effect on woodland biodiversity and maintenance (Putman, 1986; Putman et al., 1989).
The New Forest woodlands suffer from high levels of grazing by a range of herbivores.
Structural diversity severely limited under heavy grazing by preventing regeneration, sometimes missing ground-flora and shrub layers all together.
Such impacts on the vegetation have knock-on effects on associated wildlife.
Under little grazing pressure, vegetational and faunal communities are more diverse.
--- Para SEP ---
Intensive grazing on the uplands can cause community change from heather moorland to non-diverse acid grasslands, dominated by species such as Molinia and Nardus.
Scorching by urine affects heath plants and promotes aggressive grasses.
Trampling and excreta can be a problem on lowland heaths, putting wild fauna such as reptiles at risk.
--- Para SEP ---
However, grazing can be an appropriate and necessary element in the maintenance of valuable habitats, particularly plagioclimatic communities.
It has been seen that a degree of grazing is required to ensure their maintenance and high quality (Smallshire et al., 1997).
Sustainable levels of grazing intensity are crucial in maintaining high quality habitats in the long term.
If too high, a habitat will deteriorate; if too little grazing, a habitat may resume its successional pathway to woodland.
--- Para SEP ---
For example, grazing may enhance diversity of grasslands by suppressing aggressive grasses and increasing the number of bare patches by trampling into which broad-leaved grasses may colonise and establish.
Upland and lowland heath with >50% ground cover of dwarf shrubs may be maintained at high quality by subjection to low-level grazing to control invasive plants without suppressing heath vegetative growth and minimising the destructive effect of trampling.
This practice is best used in conjunction with planned small-scale burns to vary dwarf shrub age structure.
--- Para SEP ---
Other plagioclimatic communities including wetlands (reed swamps, fen meadows etc) and sand dunes are maintained by a certain level of disturbance.
Wetlands and sand dunes may be maintained to a large extent by grazing (Rieley & Page, 1990).
--- Para SEP ---
Vandvik et al.
(2005) stress the importance of traditional land management regimes such as cutting, burning, grazing and turf-cutting, to preserve diversity of landscapes that are of high priority in Europe.
--- Para SEP ---
This has been only a brief review of some of the impacts grazing has on a few habitat types of Britain.
However, it highlights the potential grazing pressure has to lower or maximise quality and value of certain habitats.
--- Para SEP ---
Unfortunately, many of Britain's habitats have lost their economic value of the past, and depleted use of traditional management practices has led to their decline.
Constant input of money into sustainable is required to ensure their existence.
--- Para SEP ---
Grants administered by the Government, often in the form of agri-environment schemes, assist organisations to manage habitats appropriately.
Over the past two decades, there has already been great improvement in reducing decline of habitats and wildlife diversity.
To name but one example, such improvements may be seen on the lowland heaths of southern Britain, which have received much attention and management by various groups including English Nature, the RSPB and the Herpetological Conservation Trust.
--- Para SEP ---
It is crucially important to preserve the mosaic of habitats and communities across the British landscape to protect and improve biodiversity in Britain, in which grazing can play a crucial role in sustainable land management in conjunction with other practices.
--- Para SEP ---
''',
'''The objective of this study was to analyse chocolate purchases with respect to individual supermarkets, types of chocolate and customer characteristics.
--- Para SEP ---
The independent sample t-test was chosen to test the null hypothesis that 'customers with kids spend the same amount on chocolate as those without' because it compares two means within the same variable.
It tests whether the two means are equal or alternatively if they show a significant difference.
The T-test is based on the assumption that the sample mean is normally distributed across the sample.
--- Para SEP ---
The ANOVA F test was chosen to find out whether the amount spent on chocolate is significantly different across 3 categories of TV watchers (light, medium and heavy).
This test is appropriate because it can compare several means simultaneously while avoiding the error that may occur in performing multiple t-tests.
The null hypothesis is that all the means are equal and it is rejected if one of them differs.
The F (Fisher) ratio compares the variance within sample groups with the variance between groups and is the basis for ANOVA. If the calculated F value is more than the critical F value then H0 (the means are equal) is rejected and H1(there is a significant difference between the means) is accepted.
--- Para SEP ---
This test assumes that the sample is normally distributed and has equal variances.
--- Para SEP ---
The P value is used to test the statistical significance of the T and F values.
--- Para SEP ---
If the P value is greater than alpha (which depends on the significance level) then the results are statistically significant and can therefore be used to draw conclusions.
--- Para SEP ---
The table below shows the average expenditure for 3 different chocolate types across 6 supermarkets by age group.
The following information is represented in a series of graphs and discussed below.
--- Para SEP ---
The graph to the left shows that for every type of chocolate, expenditure is highest for the 56-70 age group and lowest for those aged 25-40.
This however varies within in each supermarket, demonstrated in the rest of the graphs on the page.
Focusing on Sainsbury, organic chocolate expenditure follows the same pattern as above, whereas fair trade and standard chocolate vary.
Fair trade chocolate has the highest expenditure within the 41-55 age bracket at £1.76 and the lowest in the 25-40 range at 72p.
Standard chocolate expenditure is highest within the 41-55 age range at £1.64 and lowest in the 56-70 range where no chocolate at all was purchased.
The 71 - 85 age range does not appear on the graph at all because they do not shop at Sainsbury.
--- Para SEP ---
The standard deviation for fair-trade and standard chocolate across all age groups is considerably higher than the standard deviation for organic chocolate indicating a larger variation from the sample mean for these two types of chocolate.
A large variation suggests that the precision of the sample; in terms of being able to replicate the values if the research was conducted again, is low.
The width of the confidence intervals and the standard error values also reflect the reliability of the mean.
The wider confidence intervals and higher standard error of mean values indicate a less reliable mean.
The widest confidence interval is for fair trade chocolate within the 56-70 age group, this is due to the smaller sample size, which makes the results more difficult to replicate.
--- Para SEP ---
The table and graph below clearly show that, in general, average chocolate expenditure for all types of chocolate is greater for those customers with kids than it is for those without.
The difference is particularly noticeable for fair trade and organic chocolate types.
The difference in average chocolate expenditure between those with kids and those without for fair trade chocolate is £1.11 and for organic chocolate is £1.10 whereas for standard chocolate the difference is only 31p.
--- Para SEP ---
Ho: Customers with kids spend the same amount in chocolate as those without
--- Para SEP ---
H1: Customers with kids do not spend the same amount in chocolate as those without.
--- Para SEP ---
From the independent sample means test (see appendix: test 1) the T statistic is 4.206 which is above the critical T values in the table even at the 0.1% significance level which means that if the T statistic is significant we can be 99.9% certain in rejecting H0.
The P value given is 0 which is clearly less than the threshold given by any significance level which means the results are statistically significant.
Ho is rejected and H1 accepted.
There is a significant difference between the amount spent on chocolate by those customers with kids and the amount spent by those without.
The graphs above tell us that the relationship is positive so it can be said that customers with kids spend significantly more on fair-trade chocolate than those without.
In this case there is only a 0.1% chance that a type one error has occurred.
--- Para SEP ---
The T statistic for this test is 3.474 which again is above the critical T values in the table even at the 0.1% significance level meaning that if the T statistic is significant we can be 99.9% certain in rejecting H0. The P value of 0 indicates that the T statistic is significant so H0 is rejected and H1 accepted.
There is a significant difference between the amount spent on organic chocolate by customers with kids and the amount spent by those without.
Again the graphs above show a positive relationship between the two so customers with kids spend significantly more on organic chocolate than those without.
--- Para SEP ---
Again there is only a 0.1% chance that a type one error has occurred.
--- Para SEP ---
The T statistic in this test is 1.143 which does not exceed the critical T values for any acceptable level of significance, therefore if the result is significant H0 must be accepted and H1 rejected.
The P value of 0.001 shows a 99.8% significant result therefore H0 is accepted and H1 rejected.
There is no significant difference between the amount spent on standard chocolate by those with kids compared to those without.
--- Para SEP ---
Average chocolate expenditure and the difference in £'s for Sainsbury's customers with and without kids:
--- Para SEP ---
The case of Sainsbury follows the same general pattern.
Customers with kids tend to spend more on fair trade and organic chocolate than those without.
For fair trade chocolate, customers with kids spend on average £1.49 more than those without, and for organic the difference is £2.92.
Again, there does not seem to be a considerable difference for standard chocolate.
Customers with kids appear to spend on average 2p less than those without.
--- Para SEP ---
The critical T value at 33 degrees of freedom is smaller than the calculated T statistic for this test right up to the 1% significance level, which means if the result is statistically significant; we can be 99% certain in rejecting Ho and accepting H1.
--- Para SEP ---
The T statistic in this test gives a P value of 0.001 which means the test statistic is 99.8% significant, so for Sainsbury, a customer having kids does influence the amount spent on fair-trade chocolate.
The graphs show that this influence is positive, that customers with kids spend more on chocolate than those without.
--- Para SEP ---
In this case there is only a 1% chance that a type one error could have occurred.
--- Para SEP ---
The tabulated T value for this test is smaller than the calculated T value only up to the 20% significance level; therefore if the result is statistically significant we can only be 80% certain in rejecting Ho and accepting H1.
--- Para SEP ---
The P value given in this test is 0.738 which is clearly above any acceptable level of significance which means we cannot accept these results as conclusive.
--- Para SEP ---
The critical T value for this test is not less than the calculated T value (-0.019) at any acceptable level of significance therefore if the result is statistically significant, Ho would be accepted and H1 rejected.
As reflected in the graph there is very little difference between the purchases.
--- Para SEP ---
However, the P value of 0.985 shows that the result is almost 100% insignificant.
--- Para SEP ---
From the graph and table above it is clear that medium TV watchers have the highest average expenditure on all three types of chocolate.
Light watchers on average do not purchase fair trade or organic chocolate while heavy watchers have the lowest average expenditure for standard chocolate.
''', '''
--- Para SEP ---
The table and graph above show that Sainsbury's medium television watchers, on average, spend the most on all three types of chocolate and that light TV watchers do not purchase chocolate at all.
Heavy watchers are shown to purchase considerably more of fair-trade and organic chocolate than standard, whereas medium watchers purchase more of standard chocolate than the other types.
--- Para SEP ---
Ho: The amount of TV hours watched is irrelevant in explaining chocolate expenditure.
--- Para SEP ---
(The means are all equal)
--- Para SEP ---
H1: The amount of TV hours watched is a relevant factor in explaining chocolate expenditure.
--- Para SEP ---
(The means are significantly different)
--- Para SEP ---
From the results of the test summarised in the table above, the F statistic exceeds the critical F value of 4.605 where P = 0.01 which means that if the result is significant, we can be 99% confident in rejecting H0.
The P value of 0 indicates a 100% significant result therefore H0 is rejected and H1 accepted.
The amount of TV hours watched is relevant in explaining organic chocolate expenditure.
--- Para SEP ---
The F statistic in this test does not exceed the tabulated F values at any acceptable level of significance (F 0.1 = 2.3) so if the result is significant statistically then H0 must be accepted and H1 rejected.
The P value of 0.106 is below the 90% significance level (0.1) but only just which indicates that the result is not extensively insignificant and can be accepted at a slightly lower level of reliability.
--- Para SEP ---
The F statistic in this test exceeds the critical F value of 4.605 where P = 0.01 which means that if the result is significant, we can be 99% confident in rejecting H0.
The P value of 0 indicates a 100% significant result therefore H0 is rejected and H1 accepted.
The amount of TV hours watched is relevant in explaining fair trade chocolate expenditure.
--- Para SEP ---
The F value in this test is below the critical F value of 2.489 where P=0.10 so if the statistic is significant H0 must be accepted and H1 rejected.
--- Para SEP ---
The P value indicates a significance level of 0.122 which tells us we can only be 87.8% (100 - 12.2) confident that this result is significant.
The results of this test are not significant enough to draw conclusions from.
--- Para SEP ---
Again the F value in this test is below the critical F value of 2.489 where P=0.10 so if the statistic is significant H0 must be accepted and H1 rejected.
--- Para SEP ---
The P value indicates a significance level of 0.377 means we can only be 62.3% (100 - 37.7) confident that this result is significant.
This particular result is definitely not reliable enough to draw conclusions from.
--- Para SEP ---
In this test the calculated F value exceeds the critical F value (2.489) where P=0.10 which means that if the result is statistically significant then we can be 90% certain in rejecting H0.
--- Para SEP ---
The P value of 0.68 means we can be 93.2% (100 - 6.8) confident that this result is significant so H0 is rejected and H1 accepted.
The amount of TV hours watched is relevant in explaining organic chocolate expenditure for Sainsbury's customers.
--- Para SEP ---
This method is limited, particularly in analysing whether there is a significant difference between light medium and heavy TV watchers because it only identifies significant differences between the categories as a whole.
It does not tell you which categories differ from one another.
The HSD or Tukey Test could be used to locate where the differences arise.
--- Para SEP ---
From the results of task 1 it can be concluded that, in general terms the 56-70 age group spend the most on chocolate therefore marketing strategies in general should concentrate on this age bracket.
However, general advice may not be particularly helpful as this pattern varies for each individual supermarket.
--- Para SEP ---
The case of Sainsbury follows the general pattern with the 56-70 age group spending the most on chocolate and therefore marketing strategies focusing on this age range are likely to benefit Sainsbury.
It is also important for Sainsbury to know their market segment age-groups for each chocolate type in order to decide how to focus their marketing strategies.
The 56-70 age group showed the highest expenditure for organic chocolate and the 41-55 age range for organic and fair trade chocolate.
--- Para SEP ---
The results of the independent sample T-test showed that kids were an influential factor in determining the amount spent on fair trade and organic chocolate but there was no significant difference in expenditure for standard chocolate.
Again this pattern varies for each supermarket.
--- Para SEP ---
For Sainsbury, the results from the independent samples t tests were only significant for fair-trade chocolate where customers having kids' was seen to make a significant positive difference to the amount spent on this chocolate type.
--- Para SEP ---
It would therefore be profitable for Sainsbury to encourage more customers with kids to shop at the store and at the same time retain existing customers with kids as there is evidence that they spend more on at least one type of chocolate than those without kids.
One incentive to get customers with children shopping in Sainsbury might be to introduce a kids section of the supermarket.
Existing customers with kids can be retained through promotions linked to loyalty schemes, for example sending them samples to promote new fair-trade products.
--- Para SEP ---
In the knowledge that customers with kids spend more on fair-trade chocolate Sainsbury could develop marketing strategies focusing on this target segment, for example an advertising campaign directed at children promoting fair trade chocolate in a way that fits their desires.
A simpler method could be to put fair-trade chocolate at a lower position on the shelves, at a child's eye level as oppose to an adults.
--- Para SEP ---
The results of the ANOVA F-tests showed that over all of the supermarkets in general, the amount of hours of TV watched is a relevant factor is explaining fair-trade and organic chocolate expenditure but not standard chocolate expenditure.
--- Para SEP ---
For Sainsbury the one way ANOVA tests were shown to be insignificant for fair trade and standard chocolate types therefore no conclusions can be drawn specifically for these.
However, the number of hours of TV watched was found to be a relevant factor in explaining the organic chocolate expenditure of Sainsbury's customers.
The graphs show how the means differ.
Customers who watch 1-12 hours of TV a week spend the most on organic chocolate.
Those who do not watch television do not buy the chocolate at all therefore it might be advisable for Sainsbury to develop a television advertisement (to capture its target audience) promoting organic chocolate.
Watching TV and eating chocolate is often done together.
People often buy chocolate to eat whilst watching a film so other marketing strategies could include displaying some chocolate with the videos sold in the stores or linking them in promotions such as; rent this DVD and get a free bar of fair-trade or organic chocolate.
--- Para SEP ---
The objective of the study was to investigate what factors influence chocolate expenditure.
--- Para SEP ---
Independent sample T-tests and one-way ANOVA F-tests were the methodologies used.
--- Para SEP ---
Other methodologies such as linear regression could have given further indication of the relationship (how much the of the variation in expenditure was explained by the different factors).
--- Para SEP ---
Having kids is a relevant factor in explaining fair trade and organic chocolate expenditure in general (for all supermarkets).
--- Para SEP ---
Having kids is a relevant factor in explaining fair trade chocolate expenditure only for Sainsbury
--- Para SEP ---
The number of TV hours watched is a relevant factor in general (for all supermarkets).
--- Para SEP ---
The number of TV hours watched is a relevant factor in explaining organic chocolate expenditure only for Sainsbury.
--- Para SEP ---
An advertising campaign directed at children promoting fair trade chocolate could be profitable for Sainsbury.
--- Para SEP ---
A television advertisement promoting organic chocolate could be profitable for Sainsbury.
--- Para SEP ---
It would be interesting to carry out further research for Sainsbury in order to build a larger profile for its chocolate consumers which will enable the supermarket to segment its market and target consumers more effectively.
--- Para SEP ---
Segmentation involves splitting consumers up into groups of individuals with similar needs and attitudes towards the product/service in order to target them with prices and promotions consistent with their individual needs.
--- Para SEP ---
Segmentation can be conducted in many different ways.
This study has looked at psychographic (splitting consumers into groups based on the number of TV hours watched) and demographic aspects (age group and whether they have children).
--- Para SEP ---
A questionnaire could be designed to look at other demographic factors that could be explored in terms of how they affect chocolate expenditure, for example; income levels, gender, status and social class.
--- Para SEP ---
Behavioural factors would be valuable in terms of finding out what the consumer wants from chocolate as a product as they focus on the relationship between the product and the consumer.
For example, do people purchase chocolate as a gift, a single bar for their own consumption, a multi-pack for the family, or perhaps to be used in cooking?
--- Para SEP ---
How do they view chocolate? -
As a treat, a luxury, or an everyday necessity?
Do they buy more from the more reputable brands? -
and which brand is the most popular?
--- Para SEP ---
It might also be useful to look at how often it is consumed: daily, weekly or monthly.
--- Para SEP ---
Other ways of collecting this data besides a questionnaire include; focus groups, analysing the nectar card database, and buying data from classification systems such as Acorn.
--- Para SEP ---
''',
'''Manydown is a 5000 acre (2000 ha) rural estate located west of Basingstoke around the village of Wootton St Lawrence in Hampshire.
The estate is family owned and is a good example of diversification in agriculture, whereby 'not all eggs are in one basket' and income stems from a range of sources.
Based on an integrated management and sustainable practices these sources include cropping, livestock production, farm property development and perhaps most crucially to Manydown's success, a farm shop which sells home produce - a vital link for the farm to the customer both locally and nationally.
The farming system also includes conservation measures to address environmental issues.
--- Para SEP ---
This largescale operation, as table 1 suggests, requires a larger number of employees than a conventional farm - 22 full and four part time.
Richard Sterling, Manydown's director suggested how there is a successful farm team at Manydown because there is a lot of flexibility amongst workers.
This allows for multi-tasking to take place by staff and should help any problems with sickness within the workforce.
The beef production unit is organised in such a way that the beef production manager lives next to the unit, meaning that he is involved 24/7 with the unit and that the unit is always manned in the event of any problems such as calving issues occurring.
--- Para SEP ---
Beef production at Manydown is favoured as part of the livestock production due to its popularity within the farm shop but also because livestock farming suits the soil type on the farm.
The soil, typically that of Hampshire, is a flinty clay loam over chalk meaning limited fertility creating higher costs and problems for large scale arable farming on the estate.
Therefore the viability of many combinable crops is limited if the whole estate were to go into cropping.
Much of the land is grade three and not the easiest to work, so beef production seems to offer an attractive alternative.
Various considerations have to be taken into account when choosing a beef production system, as Baker (1975) summed up.
--- Para SEP ---
The 180 head beef herd is a key source of income for Manydown and is geared up for farm shop production.
The farm shop, when set up in 1994 was primarily set up for the sale of beef and this has now seen expansion to lamb, free range chickens and black pig bacon and sausages all produced on the farm.
The homebred beef herd has seen major breed development over the past ten years with increased favour for Aberdeen Angus in order to meet customer preference.
The original combination of Hereford Friesian cows crossed with Saler bulls has increasing seen Aberdeen Angus crosses to meet this demand.
This is an innovative example of Manydown producing what is demanded, not just what it is necessarily easiest to produce and as the farm directly sells its own produce this is vital to successful business.
It could be suggested that Aberdeen Angus are also used due to the breed's meat to fat ratio and growing rate.
--- Para SEP ---
As a closed herd, meaning that no new stock is bought in from markets etc, Manydown has managed an organised system to provide a constant flow of produce through the shop throughout the year.
In relation to beef, three cattle are slaughtered a week and at the other end of the scale, calving is spread out throughout spring, summer and autumn, in order to keep a steady flow of beef stock maturing and finishing throughout the year.
Steers and heifers are killed at 600kg and 550kg respectively.
The cattle system is geared to 18 months including both indoor housing and outdoor grazing.
Winter housing occurs, as on most farms, due to unsuitable field conditions outdoors in the wet and so that the cattle do not loose condition and the ability to gain weight by using a greater degree of feed energy for temperature regulation.
Summer grazing is based on 160 acres (64 ha) of permanent pasture.
Feed is a mixture of forage and concentrate with silage and cracker feed as well as milled rapeseed making up the majority of the diet.
--- Para SEP ---
Following the increase in demand for Aberdeen Angus meat and the strive at Manydown for new ideas, a recent stem has been the creation of a pedigree beef herd was established in 2000.
Originally comprising of 17 cattle from successful Canadian bloodlines, the Knightingdale Angus cattle, Manydown has bred these animals with the idea of creating a centre point to their own commercial herd in future generations.
The aim of this specialist smaller herd is for Manydown to breed its own bulls with this successful bloodline and become sufficient as unit for future meat production.
The Manydown website states this aim and relates to the importance of knowing the whole production process when selling through the farm's own farm shop and obviously by controlling all aspects of the rearing process this is more so the case:
--- Para SEP ---
In conclusion the beef unit is an important part of the estate.
It was because of the beef that the farm shop was originally set up and since has seen great expansion.
It appears in regard to livestock production as a whole that Manydown has an efficient organisation in that the company produces and markets home grown produce.
This has proved very successful and built up a widescale cliental base, including through mail ordering.
Much of the success from beef production and the farm shop as whole is related not only to quality, but also the confidence that a reputable farm shop gives the consumer - that is the produce has been home grown and hence that person does not mind paying a little bit extra for this.
There is also the public perception that Manydown is a well managed estate and deliverers sustainable farming practices which promotes the companies success.
--- Para SEP ---
''',
'''The food industry has been criticised for the increase in obesity in the UK. Consumers argue that labelling on foods is misleading and that marketing ploys are used to trick them into buying unhealthy products.
While these may be valid points, and perhaps we are occasionally tempted by the aptly placed confectionery selection at the till, personal responsibility and consumer choice cannot be rendered blameless.
--- Para SEP ---
In the following essay I intend to explore the extent to which the food industry can be blamed for the increase in obesity in the UK taking into account the changing lifestyle of the consumer.
--- Para SEP ---
Obesity in England has tripled over the last 20 years and continues to rise.
Most adults are overweight and one in five is obese.
Treating obesity costs the NHS at least half a billion pounds a year.
It is associated with an increased risk of heart disease, high blood pressure, diabetes and respiratory problems and contributed to 30,000 premature deaths in 1998.
It is a serious problem for which the concern to pinpoint the cause is understandable.
--- Para SEP ---
Obesity can be caused in a number of ways.
Psychologically a person might eat in response to emotions such as boredom, sadness or anger.
Physiologically, the hypothalamus gland in the brain regulates our appetite and if damaged can cause over-eating.
Genetic links have been found but it is very difficult to separate genetic factors from environmental ones, as families often not only share genes but also diet and lifestyle habits.
--- Para SEP ---
While there is evidence to suggest psychological, physiological, genetic, hormonal and drug-related causes of obesity, the most influential cause in the UK today is environmental.
This is the lifestyle led, the amount of food consumed and the level of physical activity undertaken.
--- Para SEP ---
The food industry obviously has an influence on consumer choices but is it solely to blame for this modern crisis?
--- Para SEP ---
Consumers remain confused by misleading health claims such as 90% fat free products that are in fact no healthier as instead of fat they are packed full of sugar to enhance the taste.
The Food Standards Agency is currently pressing for legally binding EU standards on nutrition claims and clear nutrition labelling on all foods.
However, in this instance it could be argued that it is the consumer who is to blame.
The food industry is required by law to state the correct nutritional content of food products, so if the consumer was so concerned about eating less calories then perhaps they should have looked more carefully at the label.
--- Para SEP ---
The food industry is also blamed for targeting children with advertising campaigns that promote foods high in fat, sugar and salt.
MacDonald's is a prime example.
Happy meals are used to market burgers and chips (both full of fat and salt) as a fun meal for children.
Each child receives a free gift in their happy meal.
These are often part of a set which the child will want to complete and so Mum and Dad are likely to be persuaded to take their child there again.
--- Para SEP ---
The Food Standards Agency recognises these problems and plans to work with consumers and the industry to develop a new code of practise on the promotion of foods to children.
MacDonald's has recently made an attempt to rectify the problem with the introduction of healthier options such as the salad range.
--- Para SEP ---
Marketing ploys like this are also common in supermarkets.
BOGOF (Buy one get one free) offers are more likely to be on multipacks of crisps and chocolate than fruit and vegetables.
Unhealthy snack foods are displayed at the tills and commodities such as bread and milk are often shelved at the back of the store to encourage the customer to buy other items that they see on route.
--- Para SEP ---
This may be a fault of the food industry but we as the consumers cannot be considered passive to marketing.
Adverts may make a marginal difference but we cannot ignore personal responsibility and consumer choice.
It is also important to remember that the food industry is governed by consumer demand.
--- Para SEP ---
A survey published in the British Medical Journal in January 2001, measured the body mass index of thousands of boys and girls in England and Scotland, aged between four and eleven.
The first measurements were taken in 1974, then different children were measured in 1984 and more in 1994.
The results showed that the proportion of overweight or obese children remained steady between 1974 and 1984, but increased dramatically between 1984 and 1994.
5% of English boys tested in 1984 were overweight, this figure increasing to 9% in 1994.
--- Para SEP ---
This is significant because there have been many changes in the last 20 years which have changed consumer lifestyles, dictated consumer choice and therefore affected the increase in obesity levels.
--- Para SEP ---
The last 20 years have seen various technological and economic developments leading the UK into a cash-rich, time scarce community where consumers are demanding food stuffs that are quick and easy to cook.
--- Para SEP ---
Our rising real income levels allow us to pay extra for the added service which is why eating out and take-away meals are also increasing in popularity.
''', '''
As a society, we are moving away from generalised feeding.
Families rarely have time to eat three times a day together anymore, but are more likely to graze on snacks throughout the day.
Snack foods have many advantages in a time scarce society as they do not require any special storage or preparation and can be eaten on the go, but are often full of salt, fat and sugar and contribute considerably to weight gain.
--- Para SEP ---
Working hours in the UK are amongst the highest in Europe with 1.5 million men working more than 60 hours a week.
Less time at home means that convenience foods such as ready meals, pre-prepared food and snacks are becoming increasingly popular.
These foods are again full of additives, salt, fat and sugar.
--- Para SEP ---
The modern lifestyle as a whole not only encourages snacking on unhealthy foods but also sanctions a distinct lack of exercise.
--- Para SEP ---
Occupations are far less physically demanding than 20 years ago as we have seen industry move from manufacturing to the tertiary sector.
Information technology has become fundamental for most businesses therefore more and more people are sat stationary at a desk for most of the day.
--- Para SEP ---
People have less free time due to longer working hours so technology has been used to develop strategies to make life easier.
These strategies however, are often labour saving and therefore exasperate the problem of obesity.
For example, Internet shopping means people need not even leave their home to do the weekly shop.
--- Para SEP ---
Three quarters of households own cars and with this number increasing, fewer people are choosing to walk or cycle, therefore less and less calories are being used up.
--- Para SEP ---
Professor Andrew Rugg-Gunn of the Human Nutrition Research centre at the Royal Victoria Infirmary in Newcastle carried out his own diet surveys of 12 year olds and found that although too much of their energy was coming from fat, the children's energy intake did not increase between 1980 and 1990, but their energy output decreased.
"In short they are not doing as much exercise as they should".
--- Para SEP ---
In conclusion, the food industry cannot be solely blamed for the increase in obesity in the UK. The increase in obesity has occurred due to a combination of bad diet and lack of exercise.
Clearer labelling on products and less unhealthy marketing ploys may be needed to help get society back on track but the essence of the problem lies in consumer choice.
--- Para SEP ---
Consumer lifestyle changes are mostly to blame for the increase in obesity.
Technological and economic development have changed the way people live their lives and therefore dictated the types of foods demanded and amount of exercise taken.
--- Para SEP ---
Obesity is now known as the disease of the affluent societies and appears to grow hand in hand with economic development.
--- Para SEP ---
Levels are increasing in Mediterranean countries due to globalisation, westernisation and trade despite their initial diet, famous world-wide for being healthy.
--- Para SEP ---
In order to reduce levels of obesity the government needs to create an educated population that understands the reasons for the recent increase, alongside the implementation of clearer labelling and reduced levels of fat, salt and sugar in particular food products.
--- Para SEP ---
''', '''
'Cry Freedom' is about the blacks and whites of South Africa.
The main characters of this book are Stephen Biko, a black leader, and Donald Woods who is a white newspaper editor.
Woods is thought to stand for all of white peope and this book could have an influence on them.
In the first part of this book it can be seen Woods is not on the side of the blacks although he didn't approve of the government's attitude to them. In some ways, he did not agree with "Black Consciousness" which is Biko's organization because it was too much against the whites. Woods thought he knew the black society quite well and understood their ordeals, but after he had met Biko and visited a black township, he realized he had been completely unaware of the way they had to live. The people and the circumstances he experienced in the black township were such a new world to him. Finally he changed his ideas and started to work for the blacks using his skill as a journalist, in other words, he became an activist for the black people of South Africa.
Although Biko was killed and Woods himself was declared a banned person, I would dare to say their sacrifices were worthwhile because Woods succeeded in escaping from South Africa which would enable him to publish his book revealing the truth about South Africa to the world.
In short, Cry Freedom deserves to be recommended and once you read it, you will want to read it again. Most of all, this book will make you think about the prejudice you have.
'''
]