VictorJuiz/thesis huggingface dataset:
Characterization of a virulence determinant from group A Streptococcus, identification of a novel chromosomal region responsible for streptolysin S production in Streptococcus pyogenes

Streptolysin S (SLS) is a poorly understood, non-immunogenic and oxygen-stable protein produced by Group A Streptococci and by strains of Lancefield groups C, G, E, H, L. Previously in this laboratory, a 'S. pyogenes' MGAS166 SLS- mutant, designated SBNH5, was constructed using the conjugative transposon Tn916. A 3.8 kb region flanking Tn916, containing the region associated with SLS production, was cloned into plasmid pACYC184. It was shown that this SLS- mutant was less virulent in a mouse model. The purpose of this investigation was to characterize this fragment. Sequencing of the 3.8 kb insert revealed a novel sequence, with some homology to the insertion sequence IS199 from 'Streptococcus mutans ', a transposase gene from 'Lactobacillus helviticus' and a transposase protein from 'Streptococcus thermophilus'. Tn916 was precisely mapped to base 1367 (5'-3 ') on the 3.8 kb fragment. Several putative open reading frames (ORFs) were identified. One of these, ORF 5 harbours the insertion point of Tn916 within the promoter region. Northern blot analyses revealed transcript production for ORF 5 in the wild-type (WT). However, no transcripts were produced by the mutant SBNH5 and other Tn916 generated hemolytic deficient mutants. The protein sequence of ORF 5 is inconsistent with previous biochemical studies of SLS including amino. acid composition. There are similarities between lantibiotics, and the ORF 5 peptide. A sub-group of antibiotic peptides containing modified amino acids which belongs to a class of low molecular weight, heat stable, bacteriocin-like compounds found only in gram positive organisms. In support of a functional relationship between lantibiotics and the ORF 5 peptide, cytolysin LL/LS from 'Enterococcus faecalis' was the first lantibiotic shown to be a hemolysin. These data suggest that ORF 5 encodes either a regulatory gene for SLS production or the structural gene itself. (Abstract shortened by UMI.)
Laboratory investigations in the psychophysiological detection of deception

In the psychophysiological detection of deception, the Guilty Knowledge Test (GKT) is a far more objective way of distinguishing between guilty and innocent suspects, but is less in use in field practice than the controversial Control Question Test (CQT). In an effort to contribute towards full understanding and standardization of the GKT, two experiments were carried out to examine accuracy of the GKT in a laboratory situation where participants role-played a crime scenario. Experiment I was a conceptual replication of a study by Nakayama et al. (1988), who reported that detection was superior with skin conductance response (SCR) as dependent measure, when participants were required to delay their answers for 8 seconds rather than answer immediately as is customary. In the experiment, the GKT questions were presented in a visual mode on computer screen, a procedure that is more standardized than the usual procedure where a human examiner asks the questions. The results indicated that both SCR and reaction time (RT) discriminated between relevant (larger SCR and shorter RT) and neutral items, but with no difference between immediate- and delayed-answer conditions. In Experiment II, auditory computer-synthesized voice presentation of the GKT was employed and the participant's emotional reaction to the relevant items was manipulated. To examine an orientation and habituation account of the GKT effect, a simple orienting response (OR) paradigm for obtaining participants' SCRs to repeated stimuli was carried out prior to the detection phase. The emotional-reaction manipulation did not affect detection, which, however, was again significant both for the SCR (larger) and RT (shorter). One of the OR effects, reinstated OR, showed a small but significant correlation with the GKT effect. Taken together, the present results suggest that GKT is effective regardless of response manner, and its effectiveness can be partly attributed to an attentional, orienting process in the participant, rather than to emotional factors. Additionally, computerized presentation may be useful for increasing objectivity in the detection of deception through the GKT. Non-physiological dependent variables like reaction time may also provide additional information for detection of deception.
Structural and optical characterization of hydrogenated amorphous carbon thin films

A series of hydrogenated amorphous carbon (a-C:H) semiconducting thin films was deposited using the dc saddle field glow discharge deposition technique. The ion energy during the deposition was varied to achieve films ranging from soft to hard a-C:H. In order to study the structure and the properties of a-C:H films, ultraviolet, visible, infrared, photoluminescence, and X-ray Auger electron spectroscopies, scanning electron microscopy, and mass density measurements, were used as diagnostic techniques to extract information on growth rate, mass density, sp2/sp3 ratio, hydrogen concentration, Tauc gap, photoluminescence, concentration of non-radiative recombination centers, and the degree of cross-linking of the carbon network. Based on these results, the films studied in the present research are found to consist of sp2carbon clusters of which the size increases with increasing mean ion energy during the deposition, resulting in a lower Tauc gap; this is explained in terms of the Robertson model. The growth rate of the films increases due to an increase in the concentration of unsaturated bond sites which act as chemisorption centers for radicals on the growing film surface. The increased hydrogen evolution from the film at higher ion energies results in increases in the sp2 fraction, the degree of cross-linking of the C-C network, and the mass density of a-C:H films. Atmospheric aging of soft a-C:H films reveals a decrease in the concentration of C-H bonds in a-C:H. The proposed reaction paths for the hydrolysis and oxidation of C:H films indicate that the films mainly react with water. Thermal annealing of a-C:H films in vacuum greatly influences the soft a-C:H films, in which the chemical bonds in the hydrocarbon network are restructured due to the evolution of hydrogen, which results in a graphitic structure.
Taxonomy, morphology, paleontology and phylogeny of the South American small cats (Mammalia: felidae)

All eight native species of South American small cats (SASC) are studied. They are classified into three genera using a cladistic analysis of 52 mitochondrial DNA characters and 22 morphological characters, as follows: 'Leopardus paradalis, L. wiedii, L. jacobita, Oncifelis colocolo, O. geoffroyi, O. guigna, O. tigrina' and 'Herpailurus yagouaroundi'. The taxonomic history of all SASC is reviewed. There has been much taxonomic confusion in this group, usually because early descriptions did not include differential diagnoses of species, and age variation was ignored. A key to the skulls of the SASC is presented. Included in this key are all other South or Central American felid species: 'Panthera onca, Puma concolor, Lynx rufus' and 'Felis catus'. Each species is diagnosed by a suite of characters; polymorphism abounds. The key is based on the examination of 1762 SASC skulls, and 913 skulls of the additional four species. Discriminate Functions Analysis (DFA) is used to identify 24 specimens which were difficult to identify using only morphology. An additional DFA calculated on 353 SASC skulls of 6 species (all SASC except 'L. pardalis ' and 'L. jacobita'), produced a 94.3% success rate of correct classification. The sexual and age-related variation in ocelot skulls is explored. Males are 3.2% to 8.6% larger depending on the variable and geographic origin. Age variation is highly significant; in particular, old adult skulls are significantly larger, and different in shape, than adult skulls. The type specimen of ''Felis'' 'vorohuensis ' from the early Pleistocene of Argentina is re-examined. It is not a good source of phylogenetic information, as only two of 13 features in the original description are useful. Fossils of five species of SASC, one possibly extinct, are identified from, the Lund Collection of fossils from southern Brazil, and all other known SASC fossils are reviewed. The SASC ancestor is sought amongst the known North American Mio-Pliocene felid species. DFA demonstrates that although the living genera 'Leopardus, Lynx' and 'Puma' can be largely differentially diagnosed, many fossils do not fall neatly into one of these genera. Morphometrically, the fossil species 'lacustris' appears to be 'Puma', while ' rexroadensis' might be either 'Lynx' or 'Leopardus ', and 'proterolyncis' and 'longignathus' appear most similar to 'Lynx'.
The parameters of being and acting human, the true case for moral science in the philosophy of Saint Thomas Aquinas

The following dissertation bears an historical theme: the 'true' interpretation of a moral theory advanced during the Middle Ages, and how and why this theory is misinterpreted in the modern context. Yet this historical theme is embedded within a systematic one: whether it can be validly demonstrated that moral science is. legitimate. Hence, the first two sections of the discussion are exclusively systematic in orientation. They are concerned with what general criteria must be met in order for ethics to be deemed a legitimate science, with the problems confronting any attempt to meet these criteria, and with the apparent failure of the conventional methods contrived to resolve such problems. It is in the third of five sections that a specifically historical subject is undertaken, but only because it is seen as relevant to the dissertation's systematic objective. Within the third section, three hypotheses are advanced: [1]. that the legitimacy of moral science can be validly demonstrated; [2]. that the moral philosophy of St. Thomas Aquinas can be shown to facilitate such a demonstration; and [3]. that this philosophy has been misunderstood by some modern interpreters. The remaining two sections of the discussion are devoted to proving such hypotheses. For example, the fourth section examines and deconstructs two prominent modern interpretations of Thomistic ethics; this section uncovers the inadequacies present in the views of certain modern Thomists, and exposes important details pertaining to the true nature and validity of Aquinas' moral theory. The fifth section concentrates solely upon the latter theory, especially upon its metaphysical foundations. Here, the discussion illustrates the framework in which such a theory is wrought, and expounds the general validity of the arguments which comprise it. Overall, the following dissertation has two main ambitions, both of which are pursued within the context of the systematic theme of whether the legitimacy of moral science is validly demonstrable. The first of these ambitions is to show that St. Thomas Aquinas provides such a demonstration, and to show how he does so. The second ambition is to explain how and why this demonstration has been misrepresented by modern philosophers. In the final analysis, whether these two ambitions are successfully realized is, of course, left for the reader to decide.
The effects of chemical preconditioning on physiological changes in drought-stressed plants

The use of antisenescence compounds to precondition seedlings was studied in white pine ('Pinus strobus' L.). In a preliminary study, the effectiveness of eight compounds were tested by their ability to prevent desiccation-induced membrane leakage in 'Phaseolus vulgaris '. When fed through the xylem and roots, Ambiol, spermine and aminoethoxyvinylglycine prevented the decline in water potential under drought in white pine seedlings. These compounds also ameliorated gas exchange, reduced membrane leakage and inhibited ethylene production under drought Ambiol stimulated osmotic adjustment and inhibited transpiration. Spermine increased elastic adjustment, enhanced photosynthesis and water use efficiency. These results showed that preconditioning improved water relations and gas exchange. The ability of these compounds to delay key senescence reactions in white pine was shown by the reductions in ethylene production and membrane leakage. Preconditioning with antisenescence agents may thus be a viable option to enhance survival and growth of seedling transplants.
Speaking of liberation, the emancipatory limits of Gustavo Gutiérrez's liberation theology for Latin American women

This dissertation examines the shifting meaning of liberation in the work of the Latin American liberation theologian Gustavo Gutierrez. In particular, the analysis rests on women's marginality in Gutierrez's work and liberation theologies practice in Christian Base Communities (CEBS). In order to define the gaps in Gutierrez's thinking and the practice of liberation theology in CEBS, the work of Latin American and Latina feminist theologians is introduced as a way of determining where the limitations of Gutierrez's own work are in terms of effective liberating impulses for women.
Design of a multi-fingered, passive adaptive grasp prosthetic hand, better function and cosmesis

The design of a child sized prosthetic hand capable of passive adaptive grasp is the primary goal of this research. Adaptive grasp is the ability of the fingers to conform to the shape of an object held within the hand. When the hand closes around an object, the four fingers and thumb flex inwards and independently conform to the shape of the object. The grasp of objects such as a cube, a ball, or a pyramid will result in a different final grasp configuration for the fingers and thumb. This adaptability is passively achieved by the mechanisms within the hand. The resulting design is simple and effective, not requiring sensors or electronic processing. The purpose of this hand is to provide a more secure grasp of objects, as well as to improve the dynamic and static cosmesis of the hand, so that it looks as natural as possible. A prototype hand has been built with four fingers and a thumb. All the digits can curl as they flex and straighten out as they extend. In addition, the thumb can be passively rotated to adduct or abduct. A cylinder spring mechanism has been created to achieve the passive adaptive grasp. (Abstract shortened by UMI.)
South-south transfer, a study of Sino-African exchanges

Within the context of international academic exchange, knowledge, resources, and people have moved across nations for centuries. Despite this long historical precedent, however, the present movement differs from the past in that it flows in a largely South to North direction. Today international students tend to migrate from the less industrialized to the major industrialized nations. Past research has reflected this phenomenon. Research on international student exchange has been conducted almost entirely from the perspective of the Third World student in the First World. As a result, research on the flow of international students among Third World nations is lacking. This thesis aims to begin to fill this gap and contribute to a larger understanding of international academic relations. This thesis investigates the transfer of knowledge on a South-South dimension. Specifically, it considers China's educational exchange programs for Africa, with a special concern for issues of sustainable and equitable development. A detailed description of the African student experience in China is provided through quantified data, obtained from a student questionnaire. Qualitative data, gathered through individual and group interviews with both African and Chinese parties, adds interpretive depth to the description. This data is considered in the fight of two bodies of literature related to views of international academic relations. A review of the literature on China's changing world view, with a focus on China's Third World Policy under the reign of Mao Zedong, provides the historical context for this study. The literature on the changing approaches to international academic relations, with a focus on the theories of the World Order Models Project, provides the theoretical context. These two transformative approaches to international relations form an evaluative framework in which Sino-African relations are examined within a global milieu. This study reveals that while Sino-African exchanges currently play a supportive role in the international arena, potential signs and strategies to promote greater equality are beginning to emerge from this South-South collaboration.
The tensile deformation process of polypropylene at high pressure

With the application of high pressure there were two transitions in the tensile response of polypropylene, one associated with the crystalline component and the other with the amorphous component. The first was the development of a distinct bend to lesser slope in the stress-strain curve prior to the stress maximum. This is the yield transition which is associated with the onset of crystalline flow. The second transition is a jump in the tensile response at a particular pressure. This was determined to be due to a pressure-induced rubber-to-glass transition of the amorphous component. Comparing the tensile response across these two transitions results in a more complete understanding of the interaction between the amorphous and crystalline components at various stages of tensile deformation prior to the stress maximum. Specifically, the onset of yield is attributed to the creation of a void volume of sufficient size to allow nucleation of dislocations. Based on the sensitivity of the yield stress to the glass transition pressure, it is suggested that the nucleation site is at the crystalline-amorphous interface. This geometry defines a constrained ductile interlayer which will generate the triaxial tensile state of stress necessary to form a void. The triaxial tensile state of stress required for void formation must overcome the triaxial compressive state of stress due to the hydrostatic pressure and accounts for the linearity observed between the yield stress and pressure in polymers. Deformation prior to crystalline yield is largely elastic, and is due to chain extension of the tie molecules within the amorphous component. Prior to crystalline flaw the tie molecules are effectively pinned at their entry points into the lamellae, and respond in a manner similar to an elastomeric polymer in the final state of extension. In this case the limiting strain is defined not by specimen fracture but by formation of avoid large enough to allow dislocation nucleation. The pressure dependence of the tensile modulus at finite strains is a direct consequence of the critical tensile stress required for void formation for crystalline yield coupled with the deformation response of the tie molecules which are in the final stage of elastomeric extension.
On combining motherhood with employment, an exploratory study

This dissertation will examine the experience of six working mothers in order to understand their experience of combining working with motherhood. To fully understand this issue, the following research question was formulated: what is the experience of being a working mother, what are the underlying feelings associated with this experience, and under what circumstances is the working mother affected by this experience? The research methodology used was Glaser and Strauss' "grounded theory". The philosophical approach used was the "phenomenological-hermeneutic approach". Open-ended interviews were conducted with six working mothers, who volunteered for the study. All interviews were transcribed and analyzed according to Glaser and Strauss' "constant comparative method". Two primary themes were derived from the research: (1) The working mother's ability to separate from and connect to others. This theme included the working mother's feelings of isolation and/or the yearning for others, the working mother's ability to balance work and motherhood with her own needs, the ability of the working mother to find a bridge between work and motherhood, the working mother's early relationship and losses, and the working mother's present relationships and support systems. (2) The working mother's sense of herself as feeling integrated and/or fragmented. This theme included the working mother's sense of emotional and physical well-being and the working mother's perception of time as affecting her sense of self Descriptive-interpretive summaries of each of the six interviews with working mothers were prepared in order to describe their experiences. As a result, three fluid stages to the working mother's experience were derived: the splitting working mother, the integrating working mother and the transitional working mother. Existing theory was then applied to the research findings and a new theory derived from the research presented. Practical and theoretical limitations of the study, as well as implications of the research were discussed.
The politics of Canada's nuclear policy, 1957-1963

Scholars have portrayed John G. Diefenbaker as an indecisive leader who procrastinated over whether to accept nuclear weapons for Canada. However, it is an inadequate characterisation because it explains little about his behaviour. This dissertation seeks to explain why Diefenbaker was reluctant, but willing, to accept nuclear warheads. It argues that electoral considerations, not national security, governed his formulation of nuclear policy from 1957 to 1963. Concerns about electoral expediency meant that two things governed his formulation of policy: the state of public support and the position of parliamentary opposition. This was a period of transition for protest groups in Canada as organisations moved from protest to more extensive efforts to influence government policy, something anti-nuclear organisations exemplified. This dissertation traces the origins and activities of Canada's three most prominent anti-nuclear organisations: the Canadian Committee for the Control of Radiation Hazards, the Combined Universities Campaign for Nuclear Disarmament, and the Voice of Women. How these organisations tried to convince Diefenbaker that they represented the views of the majority and why they failed are major elements of this thesis. Diefenbaker also worried about parliamentary opposition. Lester B. Pearson was particularly important in this regard. The Liberal leader's Nobel peace prize gave him added credibility when it came to matters of peace, and the prize and Pearson's repeated reference to it on the campaign trails only added to Diefenbaker's fears that the issue would be used by the Liberals for political gain. Despite these very real considerations, Diefenbaker was solely to blame for the political difficulties he faced on this issue. Had he moved forward decisively, he would have preceded the rise of the anti-nuclear movement. If he had accepted nuclear weapons in the early days of his majority mandate there would have been little opportunity for political opponents to criticise the government for indecision or inaction. Ultimately, Diefenbaker's fixation on electoral support turned out to be a self-fulfilling prophecy.

Keywords: Nuclear weapons
Government policy
History
Armes nucléaires
Politique gouvernementale
Histoire