bluuebunny/crossref_metadata_2025 huggingface dataset:
ARISTOTLE ON GEOMETRIC PERFECTION IN THE PHYSICAL WORLD
Authors: Kouremenos Theokritos
Published: September 2003

Although Aristotle is usually thought to deny the existence of physical objects with perfect geometric properties, J. Lear has argued that for Aristotle geometric properties can be perfectly instantiated in the physical world. In support of this thesis Lear has pointed mainly to

de An.

403a10- 6, where Aristotle seems to admit the existence of physical objects with so perfect geometric properties that the edge of one touches the spherical surface of the other at a point. In this paper I argue that

de An.

403a10- 6 does not commit Aristotle to the perfect instantiation of geometric properties in the physical world because the two objects assumed to touch each other at a point in this passage are not physical, as Lear takes it, but geometric: consequently,

de An.

403a10-6 cannot be taken as evidence that geometric properties are perfectly instantiated in physical objects, from which geometric objects are abstracted. In

Cael.

287b14-21, however, Aristotle notes that unlike the heaven a sphere made by a craftsman cannot be perfectly spherical and, in general, that no human artifact of whatever shape can be as geometrically perfect as the spherical heaven. This passage leaves no doubt that Aristotle denies the perfect instantiation of geometric properties in the sublunary region of his universe: some geometric properties are perfectly instantiated only in the superlunary region where the

aether

, the material of the heaven as well as of the celestial spheres that produce the apparent motions of each planet (the sun and the moon included), forms geometrically perfect spheres.
Do Cross-National Differences in Household Standard of Living Mobility Parallel Cross-National Differences in Occupational Mobility? A Comparison of Germany, Sweden and the USA
Authors: DiPrete Thomas A.
Published: September 2003

While ongoing debates in sociology exist over whether the family or the individual is the correct conceptual `unit' for stratification research, both sides to this debate have generally relied on individual-level occupation to operationalize social position. However, because industrial nations differ in the extent of labour force participation by women, stability of working hours, the stability of households and in state tax and transfer policies, comparative analysis of occupational mobility may not accurately describe cross-national differences in household mobility in living standards over the life course. Studies of standard of living mobility in the USA, Germany and Sweden show greater similarity between the countries than do studies of male occupational mobility.
Male Emotions/Relationships and Violence: A Case Study
Authors: Scheff Thomas J.
Published: September 2003

In this article, a theory of the emotional/relational origins of male violence is outlined, and illustrated by episodes in Hitler's life. Drawing on earlier work on aggression and violence, it is proposed that three conditions lead to rage and violence: (i) no affectional attachments, (ii) a single overarching obsession, and (iii) the complete repression of shame. Only to the extent that all three of these conditions are fully met is destructive violence likely. Although women in whom these three conditions were present would be as likely as men to commit violent acts, men qualify much more frequently and fully than women. Key features of the theory are illustrated by applying it to details in biographies of Hitler. This case suggests a way in which emotions unite leaders and led, leading to collective violence. Finally, a method that would provide a preliminary test of the theory is suggested.
Commercialization of Religious Objects: A Comparison between Traditional and New Age Religions
Authors: Zaidman Nurit
Published: September 2003

The present study is an attempt to understand the differences between modern and traditional religions regarding trade in religious goods. It presents an analysis of the world of goods and participants' cultural worlds, as well as the transformation of meaning in objects. The study focuses on members of two different subcultures in Israel: New Agers and Jews of North African origin who are involved in pilgrimage to local saints' tombs. The results show that traditional and New Age subcultures differ with regard to participants' perspectives on the commercialization of religious goods, the role of marketing agents, and the general characteristics of the market.
The Challenges of Institutionalization for AIDS Media Activism
Authors: Gillett James
Published: September 2003

Since the early 1980s, AIDS activists have developed their own alternative media projects in order to mobilize those infected and affected, challenge misconceptions regarding the disease, provide practical and useful information, and transform power structures which inhibit an effective response to the HIV/AIDS pandemic. In this article I examine several challenges for AIDS media activists arising from an expanded institutional response to the HIV/AIDS epidemic. First is the challenge posed by pressures to professionalize media projects for people with HIV/AIDS. The second challenge is the need to adapt the role of media projects as providers of information in relation to those institutional resources that are available to people with HIV/AIDS. Third is the challenge of overcoming the marginality of alternative media projects in order to effectively reach out to and inform people with HIV/AIDS and in order to continue to work toward transforming the meaning of HIV/AIDS. To conclude, I address the relevancy of AIDS specific struggles with institutionalization for media activism more broadly. This analysis provides insight into the dialectic between activists using media to challenge and transform the meaning of social problems and institutional forces of incorporation and containment exercised by the state, medicine, and the mass media.
Whither Mass Media and Power? Evidence for a Critical Elite Theory Alternative
Authors: Davis Aeron
Published: September 2003

This article makes the case that critical research in media studies needs to devote more attention to the part played by media and culture in elite decision-making. It argues that the mass media/mass influence paradigm is, of itself, no longer adequate to explain the utility of communications in the sustenance of unequal power relations in society. Instead, evidence presented here observes that a major function of news media is to act as a communications forum for elites in their daily conflicts and negotiations. With elites acting as sources, targets and major recipients of news texts, inter-elite, rather than elite-mass, communications seems to be a key feature of the political process. These findings are based on a series of 98 semi-structured interviews with political and corporate news sources, and senior journalists in the UK.
Group Analysis has No Theory! Foulkes Failed Us. Did He?
Authors: Dahlin Olov
Published: September 2003

In the form of an essay the author addresses the conditions of group analysis today from a metatheoretical point of view using Foulkes's dictum that every group is part and product of its context. Articles in recent issues of Group Analysis are used to show a dilemma in the development of group-analytic theory and practice. The author's thesis is that group analysis in consort with psychoanalysis, on which group analysis has come to feed, has been marginalized by market forces and has been allocated to the psychotherapeutic corner of the market, where its praxis and its theorizing have been pruned by the ruling medical discourse, leaving no space for the social dimension of group analysis. While group analysis has stuck to that horn of the dilemma, trapped in the psychotherapeutic corner, many group-analysis-like inceptions can be observed in, for example, social anthropology, business administration and the studies of organizations. Those inceptions cannot as a rule acknowledge any connection with group analysis. One must conceive of them as stemming from the same roots as group analysis but not dependent on group analysis. There is a risk that group analysis will be left astern. It is the author's opinion that Foulkes gave us little theory but very much in the form of praxis.
Encouraging Personal Agency in Analytic Group Therapy
Authors: Rubenfeld Sy
Published: September 2003

Analytic thought and also group-analytic writers understate or do not comprehend the centrality of human purposiveness. A theory of personal agency in terms of analytic goup therapy is offered to contrast with a prevailing idea that a thinking, feeling, evaluating self oversees reactions. Clinical examples emphasize the usefulness of mobilizing patients' intentions. An example of an active group therapist role is offered that seeks to mobilize members' willingness to explore their enactments of problems in the group. I discuss the rationale and methods involved in this method in terms of my clinical experience and conclusions in line with the theory set forward in the paper.
Still Thriving, the Daily Sketch
Authors: Letts Quentin
Published: September 2003

Political sketchwriting is sometimes thought to be the hardest of Fleet Street's circus turns. The sketchwriter is an unpredictable beast, sometimes indolent, often freelance, invariably edgy and just occasionally the worse for wear. He (a "she" is rare) exists in the no-man's land between comment and news, dependent on the patronage of distracted editors and the "co-operation" of subs who reckon they know a better use for the space. The material, moreover, is hardly that sexy.
From Political Landscape to Political Timescape
Authors: Weltman David
Published: September 2003

Recent changes in British politics can be partly understood in terms of the gradual replacement of political division in space by political division in time. This article explores that development by examining local politicians’ accounts of political time. In the main, the rise of Third Way consensus politics was found to be represented as either a progressive or regressive development, although the former version was by far the most common. In addition, some councillors were seen to face an ‘ideological dilemma’ between recognizing the recent emergence of non-partisan politics and a preference for a timeless non-partisanship for self.
Understanding the Experience of Time Scarcity
Authors: Kaufman-Scarborough Carol , Lindquist Jay D.
Published: September 2003

In this study we examine the concept of time scarcity in relation to individuals’ time-personalities. That is, we propose that when individuals experience high levels of time scarcity, they are likely to have certain ways of thinking about and using time that may reinforce their experience of time shortage. In order to examine these potential linkages, we examine the responses of adult heads of households regarding their habitual methods of planning and using their time. We also extend our investigation to the consumer realm to identify whether time-personality variables associated with time scarcity are also associated with marketplace inefficiencies. Following precedent in time construct analysis, a stepwise regression was used to examine and identify a set of time-personality variables that predict an individual’s perceptions of time scarcity. Correlations are also found between the time-personality variables and several marketplace behaviors.
A Concept Analysis of the Role of Fatherhood: A Japanese Perspective
Authors: Iwata Hiroko
Published: September 2003

A concept analysis of the father's role is presented from a Japanese perspective. To conceptualize the term father's role, the process for concept analysis was employed. The analysis resulted in a definition of the term and four defining attributes. Two dimensions of the father's role emerged as being most commonly used or implied: a behavioral dimension and a consequential dimension. Each of these dimensions had another four subcategories in terms of the direction of the consequences: those were to the child, the mother, the family, and the father himself. The findings will assist in instrument development and to a further understanding of the concept that will stimulate nursing theory development and research.
Culturally Interpreting Environment as Determinant and Experience of Health
Authors: Bent Katherine N.
Published: September 2003

In minority communities, experiences of the environment and health disparities are frequently related. An important component of nursing practice in communities is to address these issues in cultural context to improve overall community health experiences. This present ethnographic study was conducted in an urban barrio community in which residents have responded to health threats posed by local environmental hazards with sustained community-focused health and development strategies. Data generation occurred during field visits in the community and included interviews, participant observation, field notes, participant-drawn maps, examination of artifacts and existing documents, and photography. Two dimensions define the community experience of the environment in this community: contamination and unhealthy community. The environment is a complex and multidimensional concept of central importance to community experiences. Environmental health cannot be addressed without first understanding that experience in cultural context.
An Exploration of the Experiences of Cultural Safety Educators in New Zealand: An Action Research Approach
Authors: Wepa Dianne
Published: September 2003

This research is a study of the experiences of four cultural safety educators in nursing education in Aotearoa, New Zealand. Action research methods assisted the participants to implement change in their practice and gain positive personal involvement in the study. Reflective diaries provided the major tool in this process as participants were able to achieve at least one action research cycle by identifying issues, planning action, observing the action, and reflecting. The findings of the research revealed that the participants not only coped with everyday stressors of teaching but were also required to formulate knowledge for cultural safety. For the Maori participants, their stress was confounded with recruiting and retaining Maori students and macro issues such as commitment to their iwi (tribe). Lack of support to teach cultural safety was identified to be a key theme for all participants. An analysis of this theme revealed that many issues were organizational in nature and out of their control. Action research provided a change strategy for participants to have a sense of control of issues within their practice. Recommendations include the following: support for cultural safety educators to have a dialogue on a regular basis, the introduction of nurse educator programmes, paid leave provisions for educators to conduct and publish research so that a body of knowledge can be developed, and that Maori cultural safety educators be recognised for their professional and cultural strengths so that they do not fall victim to burnout.
Nerdy, Trendy or Healthy? Configuring the Internet Café
Authors: Lægran Anne Sofie , Stewart James
Published: September 2003

This article analyses how internet cafés, understood as technosocial spaces, are configured in the intersection of human and non-human actants. Based on empirical studies in Scotland and Norway, the article shows how internet cafés are not just adapting a universal concept in the process of configuration, but that some shared images are played with in different ways. The nerdy, trendy and healthy are translocal images that are played with in the configuration process, creating locally specific and embedded spaces. The article further looks at the various ways the internet is used in the cafés, identifying two forms of extenders, as well as players, who in different ways create new social spaces based on the internet café. The article concludes that the internet café is neither a footloose space nor entirely locally embedded, but that spaces are configured in the intersection of translocal images and local circumstances.
On having Voice and Being Heard
Authors: Ross Fiona C.
Published: September 2003

In much recent theorizing, the memory of violence is considered to constitute the post-colonial subject. The article is placed at the intersection of two arguments about the role of voice and memory, particularly memories of violence, in the constitution of the self and the collective. Richard Werbner (1998) has argued that `rights of recountability' are fast becoming part of the political arena as citizens seek to make themselves heard and acknowledged in the public sphere. Achille Mbembe (2000) traces modes of voice through the discourses of powerlessness. Here I consider the ways in which testimonies circulate in public spheres in the aftermath of South Africa's ambitious Truth and Reconciliation Commission. The impetus is drawn from the work of the Commission's Human Rights Violations Committee, which elicited powerful and moving testimonies couched in terms of victimhood. However, many, having testified, are alarmed at the ways in which their testimonies proliferate outside the contexts of individual control. The article raises questions about the effects of wide circulation on individuals' understandings of self and seeks a theory of vulnerability.
Aspects of Spirituality in Dementia Care
Authors: Lawrence Robert M.
Published: September 2003

Clinicians dealing with persons with dementia are usually unable to maintain communication with the individual beyond the available psychometric tests that only give a crude evaluation of the person's capacity to express thoughts and feelings. Evidence from the elderly with terminal illness and functional psychiatric illness shows that the individual tends to `journey' back to reassuring and positive experiences and that religious matters are of paramount importance in dealing with terminal illness and death. Normal communication channels are precluded for individuals with dementia, as they gradually lose the ability to use understandable speech. The clinician may partly circumvent loss of communication by gathering a holistic and comprehensive view of the person's spiritual background at the very outset and by incorporating this holistic view into the care plan.
The intronic prothrombin 19911A>G polymorphism influences splicing efficiency and modulates effects of the 20210G>A polymorphism on mRNA amount and expression in a stable reporter gene assay system
Authors: von Ahsen Nicolas , Oellerich Michael
Published: September 2003

The common prothrombin gene cleavage site mutation 20210G>A is associated with elevated prothrombin levels and thrombosis. The pathomechanism of the 20210G>A mutation was explained by increased mRNA formation and/or more efficient translation. Human studies also showed an influence of the intronic 19911A>G polymorphism on prothrombin activity. We established HepG2 cell lines stably transfected with prothrombin mini-genes containing the last 2 prothrombin exons, the last intron, 3′ untranslated region (UTR), and flanking sequence. The highest mRNA expression and protein activity resulted from the mutant haplotype 19911A-20210A. Haplotypes with wild-type cleavage site (19911A-20210G, 19911G-20210G) also differed significantly as a consequence of the intronic 19911 mutation; the 19911G-20210G haplotype showed lower expression than the 19911A-20210G haplotype, whereas previous clinical studies have reported elevated prothrombin activity with the 19911G-20210G haplotype. The cleavage site pattern was homogeneous with 20210A, which may cause a favorable intracellular processing, and heterogeneous with 20210G. In an independent assay for splicing efficiency, 19911G showed about 30% higher efficiency than 19911A. We conclude that the intronic 19911A>G single nucleotide polymorphism is itself functional and changes splicing efficiency by altering a known functional pentamer motif. Further studies are needed to define the value of additional prothrombin 19911 genotyping for thrombophilia screening, especially in cases heterozygous for 20210G>A.
Annexin II mediates plasminogen-dependent matrix invasion by human monocytes: enhanced expression by macrophages
Authors: Brownstein Carrie , Deora Arunkumar B. , Jacovina Andrew T. , Weintraub Rebecca , Gertler Menard , Khan K. M. Faisal , Falcone Domenick J. , Hajjar Katherine A.
Published: September 2003

Monocytes and macrophages participate in a wide variety of host defense mechanisms. Annexin II, a fibrinolytic receptor, binds plasminogen and tissue plasminogen activator (t-PA) independently at the cell surface, thereby enhancing the catalytic efficiency of plasmin production. We demonstrated previously that annexin II on the surface of both cultured monocytoid cells and monocyte-derived macrophages promotes their ability to remodel extracellular matrix. Here, we demonstrate that human peripheral blood monocytes represent the major circulating annexin II–expressing cell. Annexin II supported t-PA–dependent generation of cell surface plasmin and the matrix-penetrating activity of human monocytes. Compared to polymorphonuclear leukocytes, monocytes supported a 12.9-fold greater rate of plasmin generation in the presence of exogenous t-PA, and this activity was largely attributable to annexin II. Likewise, anti–annexin II IgG directed against the t-PA–binding tail domain inhibited plasminogen-dependent, cytokine-directed monocyte migration through extracellular matrix. On differentiation of monocytes to macrophages, there was a 2.4-fold increase in annexin II–specific mRNA, and a 7.9-fold increase in surface annexin II. Thioglycolate-elicited peritoneal macrophages, furthermore, displayed an additional 3.8-fold increase in annexin II surface expression compared with resident cells. Thus, annexin II–mediated assembly of plasminogen and t-PA on monocyte/macrophages contributes to plasmin generation, matrix remodeling, and directed migration.
Differential contribution of Wiskott-Aldrich syndrome protein to selective advantage in T- and B-cell lineages
Authors: Konno Akihiro , Wada Taizo , Schurman Shepherd H. , Garabedian Elizabeth K. , Kirby Martha , Anderson Stacie M. , Candotti Fabio
Published: September 2003

Somatic mosaicism because of in vivo reversion has been recently reported in a small number of patients affected with Wiskott-Aldrich syndrome (WAS). Flow cytometry analysis of WAS protein (WASP) expression has shown that these patients carried revertant cells only among T lymphocytes. Here, we have used high-resolution capillary electrophoresis to analyze genomic DNA from highly purified cells of one of these patients and detected revertant sequences also within the B-cell fraction. The demonstration of revertant cells among both T and B lymphocytes in this patient is consistent with the reversion event having occurred in a common lymphoid progenitor. However, although WASP-expressing T cells showed selective advantage and were readily detectable in the periphery of the mosaic patient, revertant B lymphocytes remained below the detection threshold of flow cytometry. These findings suggest that, contrary to T cells, differentiation and survival of B lymphocytes is minimally dependent on WASP.
Aberrant methylation of DAP-kinase in therapy-related acute myeloid leukemia and myelodysplastic syndromes
Authors: Voso Maria Teresa , Scardocci Alessandra , Guidi Francesco , Zini Gina , Di Mario Antonella , Pagano Livio , Hohaus Stefan , Leone Giuseppe
Published: September 2003

Death-associated protein kinase (DAP-kinase), a proapoptotic serine/threonine kinase, is a candidate tumor suppressor gene. We studied the methylation status of DAP-kinase of 194 bone marrow samples from 160 patients with acute myeloid leukemia (AML) and 34 with a myelodysplastic syndrome (MDS) at the time of initial diagnosis by polymerase chain reaction (PCR). Hypermethylation of DAP-kinase was present in 27.5% (44 of 160) of AML and in 47% (16 of 34) of MDS specimens and significantly correlated to loss of DAP-kinase expression (P = .008). It was significantly more frequent in AML secondary to therapy for other malignancies (s-AML; 14 of 29, 48.3%), as compared to de novo AML (30 of 131, 22.9%, P = .01). DAP-kinase hypermethylation in AML was associated with myelodysplastic changes in the bone marrow at the time of the initial diagnosis (P = .002) and with the presence of cytogenetic abnormalities (P = .02). Alteration in the apoptotic response due to the loss of DAP-kinase function may be an early event in the transformation pathway to secondary leukemia via myelodysplasia.
Pulmonary vascular involvement in chronic obstructive pulmonary disease
Authors: Voelkel N.F. , Cool C.D.
Published: September 2003

Chronic obstructive lung disease affects the entire lung, not just the airways. Although pulmonary hypertension (PH) has long been recognised in a subset of patients with COLD, the important pathophysiological questions remain unanswered. Oxygen supplementation, however, has been shown to blunt the exercise-induced PH in these patients. Hypercoagulability has also been described in patients with COLD. This may, in part, be due to the inflammatory aspects of COLD exacerbation events. In addition to perivascular inflammation, the pathology of vessels in COLD includes intimal thickening, muscularisation of arterioles,in situthrombosis, loss of capillaries and precapillary arterioles, and vascular congestion and stasis. Recent work describes apoptosis of septal endothelial cells and decreased expression of vascular endothelial growth factor (VEGF) and one of its receptors, VEGFRII, in lungs from patients with emphysema. Based on this work, a rat model was developed that shows chronic blockade of VEGF receptors leads to septal cell apoptosis and results in emphysema and PH. This animal model has led to prevention trials using 1) a broad-spectrum caspase inhibitor, 2) a superoxide dismutase mimetic, and 3) α1‐antitrypsin.

These findings highlight the importance of vascular endothelial growth factor, apoptosis, oxidative stress and protease activity in the pathogenesis of emphysema. They also underscore the importance of the vasculature in what is traditionally thought of as an airways disease. Future treatment strategies need to address the vascular components of chronic obstructive lung disease.
Sleep-related hypoxaemia and excessive erythrocytosis in Andean high-altitude natives
Authors: Spicuzza L. , Casiraghi N. , Gamboa A. , Keyl C. , Schneider A. , Mori A. , Leon-Velarde F. , Di Maria G.U. , Bernardi L.
Published: September 2003

To determine whether nocturnal hypoxaemia contributes to the excessive erythrocytosis (EE) in Andean natives, standard polysomnographies were performed in 10 patients with EE and in 10 controls (mean haematocrit 76.6±1.3% and 54.4±0.8%, respectively) living at an altitude of 4,380 m. In addition, the effect of O2administration for 1 h prior to sleep, and the relationship between the hypoxic/hypercapnic ventilatory response and the apnoea/hypopnoea index (AHI) during sleep were studied.

Awake arterial oxygen saturation (Sa,O2) was significantly lower in patients with EEthan in controls (83.7±0.3%versus85.6±0.4%). In both groups, the meanSa,O2significantly decreased during sleep (to 80.0±0.8% in EE and to 82.8±0.5% in controls). The meanSa,O2values remained significantly lower in patients with EE than in controls at all times of the night, and patients with EE spent significantly more time than the controls with anSa,O2of <80%. There were no differences between the two groups in the number and duration of the apnoeas/hypopnoeas. None of these variables were affected by O2administration. In both groups the AHI positively correlated with the hypercapnic ventilatory response.

Andean natives undergo minor respiratory disorders during sleep. The reduction inoxygen saturation found in subjects with excessive erythrocytosis was small, yet consistent and potentially important, as it remained below the threshold known for theincrease in erythropoietin stimulation. This may be an important factor promoting erythropoiesis, but its relevance needs to be further explored.
Extracellular cues and pioneers act together to guide axons in the ventral cord ofC. elegans
Authors: Hutter Harald
Published: September 2003

The ventral cord is the major longitudinal axon tract in C. elegans containing essential components of the motor circuit. Previous studies have shown that axons grow out sequentially and that there is a single pioneer for the right axon tract which is important for the correct outgrowth of follower axons. Here, the dependencies between early and late outgrowing axons in the ventral cord were studied systematically with laser ablation experiments and a detailed analysis of mutants using multi-color GFP markers. Different classes of axon were affected to a different extent when the AVG pioneer neuron was eliminated. In the majority of the animals, axons were able to grow out normally even in the absence of the pioneer, suggesting that its presence is not absolutely essential for the correct outgrowth of follower axons. The transcription factor LIN-11 was found to be essential for the differentiation and pioneering function of the AVG neuron. UNC-30 appears to play a similar role for the PVP pioneer neurons. Later outgrowing axons typically do not simply follow earlier outgrowing ones, but subtle dependencies between certain groups of early and late outgrowing axons do exist. Different groups of axons growing in the same axon bundle apparently use different combinations of guidance cues for their navigation and can navigate largely independently.
Intracellular transport of human immunodeficiency virus type 1 integrase
Authors: Devroe Eric , Engelman Alan , Silver Pamela A.
Published: September 2003

The human immunodeficiency virus type 1 integrase protein has karyophilic properties; that is, it localizes to the cell nucleus according to a range of assays. As an essential component of the preintegration complex, it has been suggested that the karyophilic properties of integrase might facilitate transport of the preintegration complex through the nuclear pore complexes of nondividing cells. However, no experiments have satisfactorily identified a nuclear localization signal within integrase. In this work, we investigated the karyophilic properties of integrase in intact cells with hopes of identifying a genuine transferable nuclear localization signal. Our results confirm that integrase tightly binds chromosomal DNA in vivo. However, our analysis determined that large integrase fusion proteins are unable to access the nucleus, indicating that integrase might lack a transferable nuclear localization signal. In addition, we present several lines of evidence to indicate that DNA binding might facilitate integrase nuclear accumulation. Furthermore, our data indicate integrase is degraded in the cytoplasm by a proteasome-dependent process, an event that probably contributes to the apparent nuclear accumulation of integrase. These results provide new insight into human immunodeficiency virus type 1 integrase intracellular dynamics.
Blocking malaria parasite invasion of mosquito salivary glands
Authors: James Anthony A.
Published: September 2003

Release of genetically engineered mosquitoes resistant to parasite infections has been proposed as a novel way to control malaria transmission,and several important advances have been made in anticipation of testing this approach. In particular, the development of synthetic effector genes that block parasite development in mosquito hosts has exploited a number of different mechanisms that result in parasite-resistant phenotypes, and those that target specifically the sporozoites are reviewed here. The use of a number of synthetic genes based on different mechanisms in transgenic mosquitoes will make the selection of resistant parasites unlikely.
Monitoring antimalarial drug resistance: making the most of the tools at hand
Authors: Plowe Christopher V.
Published: September 2003

Most countries in resource-poor, malaria-endemic areas lack current and comprehensive information on antimalarial drug efficacy, resulting in sub-optimal antimalarial treatment policies. Many African countries continue to use chloroquine despite very high rates of resistance, and others have changed policies based on limited data, with mixed success. Methods for measuring antimalarial drug efficacy and resistance include in vivostudies of clinical efficacy and parasitological resistance, in vitrosusceptibility assays and molecular markers for resistance to some drugs. These methods have the potential to be used in an integrated fashion to provide timely information that is useful to policy makers, and the combined use of in vivo and molecular surveys could greatly extend the coverage of resistance monitoring. Malawi, the first African country to change from chloroquine to sulfadoxine/pyrimethamine at the national level, serves as a case study for resistance monitoring and evidence-based antimalarial policies. Molecular, in vitro and in vivo studies demonstrate that chloroquine-sensitive parasites reemerged and now predominate in Malawi after it switched from chloroquine to sulfadoxine/pyrimethamine. This raises the intriguing possibility of rotating antimalarial drugs.
Open reduction and internal fixation of comminuted fractures of the radial head using low-profile mini-plates
Authors: Ikeda M. , Yamashina Y. , Kamimoto M. , Oka Y.
Published: September 2003

Between 1996 and 2000, we treated ten patients with severely comminuted fractures of the radial head using low-profile mini-plates. Their mean age was 42 years (24 to 71). Three fractures were Mason type III and seven were Mason-Johnston type IV. At a mean follow-up of 28.5 months (15 to 44), all fractures had united. The plates were removed in nine patients.

No patient had difficulty with daily activities or symptoms of instability of the elbow. The mean range of flexion of the elbow was from 7° to 135°, with 74° of supination and 85° of pronation. According to the Broberg and Morrey functional elbow index, the mean score was 90.7 points (73 to 100), and the outcome was excellent in three patients, good in six and fair in one.

These results compare favourably with those reported previously. The technique is applicable to severely comminuted fractures of the radial head which otherwise would require excision.
Arthroscopic treatment of osteochondral lesions of the talus
Authors: Robinson D. E. , Winson I. G. , Harries W. J. , Kelly A. J.
Published: September 2003

We reviewed, retrospectively, 65 patients who had undergone arthroscopic treatment for osteochondral lesions of the talus. The 46 men and 19 women with a mean age at operation of 34.25 years, were followed up for a mean of 3.5 years. The medial aspect was affected in 45 patients and the lateral aspect in 20. All the lateral lesions and 35 (75%) of the medial lesions were traumatic in origin. Medial lesions presented later than lateral lesions (3 v 1.5 years) and had a much greater incidence of cystic change (46% v 8%).

At follow-up, 34 patients had achieved a good result, and 17 and 14 fair and poor results, respectively. Of the 14 poor results, 13 involved medial lesions. Cystic lesions had a poor outcome in 53% of patients. Excision and curettage led to better results than excision and drilling of the base. Further arthroscopic surgery for patients with a poor result was disappointing. There was no association between outcome and the patient’s age.
Painful nonunion after triple pelvic osteotomy
Authors: Tschauner C. , Sylkin A. , Hofmann S. , Graf R.
Published: September 2003

Tönnis triple pelvic osteotomy is an accepted technique to correct acetabular dysplasia and degenerative labral pathology. A series of 409 consecutive patients who underwent a triple pelvic osteotomy between 1987 and 1999 were followed for a mean of 7.1 years (2 to 15). Five patients (1.2%), all women, developed a double nonunion and required revision, which involved excision of the pseudarthrosis, autologous bone grafting and osteosynthesis with screws or reconstruction plates. Bony healing was achieved in all after a mean of 7.8 months.
The natural history of spontaneous osteonecrosis of the medial tibial plateau
Authors: Satku K. , Kumar V. P. , Chong S. M. , Thambyah A.
Published: September 2003

The natural history of spontaneous osteonecrosis of the medial tibial plateau remains controversial and incomplete. We have studied 21 patients (aged between 53 and 77 years) with clinical and scintigraphic features of spontaneous osteonecrosis of the medial tibial plateau who were observed prospectively for at least three years (37 months to 8.5 years). The mean duration of follow-up was 5.6 years.

The mean duration of symptoms at presentation was 4.7 weeks (3 days to 12 weeks). Radiographs of the affected knee at the first visit were normal in 15 patients and mildly arthritic in six. The characteristic radiographic lesion of osteonecrosis was noted at presentation in five of the mildly arthritic knees and during the evolution of the disease in eight of the radiographically normal knees. During the follow-up, subchondral sclerosis of the affected medial tibial plateau was noted in 16 knees.

There are three distinct patterns of outcome: 1) acute extensive collapse of the medial tibial plateau in two knees within three months of onset; 2) rapid progression to varying degrees of osteoarthritis in 12 knees, in eight within a year, in all within two years and deterioration of the pre-existing osteoarthritis in three; and 3) complete resolution in four knees, two of which were normal at presentation and two mildly osteoarthritic.

The two patients with acute extensive collapse and three who had rapid progression to severe osteoarthritis required total knee arthroplasty.

We conclude that osteonecrosis of the medial tibial plateau progresses in most cases to significant degenerative disease of the knee.
Thermal and mechanical properties of plasticized poly(L‐lactic acid)
Authors: Baiardo Massimo , Frisoni Giovanna , Scandola Mariastella , Rimelen Michel , Lips David , Ruffieux Kurt , Wintermantel Erich
Published: September 2003

Acetyl tri‐n‐butyl citrate (ATBC) and poly(ethyleneglycol)s (PEGs) with different molecular weights (from 400 to 10000) were used in this study to plasticize poly(L‐lactic acid) (PLA). The thermal and mechanical properties of the plasticized polymer are reported. Both ATBC and PEG are effective in lowering the glass transition (Tg) of PLA up to a given concentration, where the plasticizer reaches its solubility limit in the polymer (50 wt % in the case of ATBC; 15–30 wt %, depending on molecular weight, in the case of PEG). The range of applicability of PEGs as PLA plasticizers is given in terms of PEG molecular weight and concentration. The mechanical properties of plasticized PLA change with increasing plasticizer concentration. In all PLA/plasticizer systems investigated, when the blend Tg approaches room temperature, a stepwise change in the mechanical properties of the system is observed. The elongation at break drastically increases, whereas tensile strength and modulus decrease. This behavior occurs at a plasticizer concentration that depends on the Tg‐depressing efficiency of the plasticizer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1731–1738, 2003
Use of rheological compatibility criteria to study SBS modified asphalts
Authors: M Yvonne Becker , Müller Alejandro J. , Rodriguez Yajaira
Published: September 2003

Polymer‐modified asphalts (PMAs) were prepared using Bachaquero asphalt and styrene–butadiene–styrene (SBS) type copolymers. Their rheological behavior was compared to that of unmodified asphalt and of a compatible commercial PMA. Materials were submitted to frequency sweeps between 10−1and 102rad/s from 0 to 50°C. Storage stability tests were performed for 72 h at 160°C. Ring and ball softening points from the top and the bottom of the blends were compared and were used along with fluorescence microscopy to evaluate stability. Samples prepared with styrene–ethylene–butylene–styrene (SEBS) showed improved compatibility and stability as compared with SBS‐modified asphalts, probably because of a higher stability to thermal degradation from the absence of double bonds. An additional improvement in stability and compatibility was observed for SEBS functionalized with maleic anhydride (SEBS‐g‐MAH)–modified blends. Better compatibility, however, did not improve rheological behavior at low temperatures. The systems studied are so complex from a chemical point of view that the rheological criteria normally used to predict compatibility of polyblends did not give enough information regarding the compatibility of the modified asphalts. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1772–1782, 2003
Study of blend films from chitosan and hydroxypropyl guar gum
Authors: Xiao Chaobo , Zhang Jinhua , Zhang Zhenjun , Zhang Lina
Published: September 2003

In this study blend films of chitosan (CH) and hydroxypropyl guar gum (HGG) were prepared using a conventional solvent‐casting technique and were dried at room temperature. Their miscibility and other properties were studied by Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, scanning electron microscopy, differential thermal analysis, ultraviolet analysis, and tensile strength tests. The physical and thermal properties of the films depended on the blending ratio. The maximum tensile strength and breaking elongation values achieved were 58.94 MPa and 17.25%, respectively, with a 60% content of HGG. Thermal stability also was improved, and the blend film containing 60% HGG had greater thermal stability than did the other blend and pure CH films. In addition, the best optical transparence was observed from 500 to 800 nm in the blend film containing 60% HGG. The results indicate that intermolecular interactions that resulted from hydrogen bonding between CH and HGG occurred in the blend films. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1991–1995, 2003
Antimicrobial activity of a monomer and its polymer based on quinolone
Authors: Moon Woong‐Sig , Chul Kim Jae , Chung Kyoo‐Hyun , Park Eun‐Soo , Kim Mal‐Nam , Yoon Jin‐San
Published: September 2003

An acryl monomer containing the quinolone moiety was synthesized and then polymerized with azobisisobutyronitrile in a dimethylformamide solution. The resulting polymer as well as the corresponding monomer exhibited an excellent antibacterial activity. The poly(acrylated quinolone) (PQ) was compounded with other ordinary synthetic polymers such as low‐density polyethylene (LDPE), poly(butylene succinate) (PBS), poly(methyl methacrylate) (PMMA), maleated polypropylene (PPMA), and polycaprolactone (PCL). The polymer blends reduced the viable cell number significantly on contact during the shake flask test even when the PQ content was as low as 1 wt %. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1797–1801, 2003
Hole injection initiated by ionic conduction in electrically stressed insulating polymers
Authors: Kao Kwan C. , Tu Demin
Published: September 2003

A new mechanism leading to hole injection into insulating polymers under normal operating fields is presented. In general, it is unlikely that holes can be injected into large band‐gap insulating materials under normal operating fields less than 1 MV cm−1, particularly for materials that are not in the form of thin films. However, insulating polymers consist of a large amount of various unavoidable ionic impurities, so ionic conduction plays an important role in their electrical properties. The presence of such ions modifies the field distribution in the material with the tendency of enhancing the field toward the anode, thus increasing the probability for hole tunneling from the anode to the material. The appearance of positive space charge near the anode after a prolonged period of electrical stressing, as observed by many investigators, may be considered as the experimental evidence of the mechanism. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1864–1867, 2003
Correlation between limiting oxygen index and phosphorus/nitrogen content of cotton fabrics treated with a hydroxy‐functional organophosphorus flame‐retarding agent and dimethyloldihydroxyethyleneurea
Authors: Wu Weidong , Yang Charles Q.
Published: September 2003

The combination of a hydroxyl‐functional organophosphorus flame‐retarding agent (FR) and dimethyloldihydroxyethyleneurea (DMDHEU) was used as a durable flame‐retardant finish system for cotton fabrics. DMDHEU functions as a binder between FR and cotton cellulose, thus making this flame‐retarding system durable to home laundering. DMDHEU also provides nitrogen to this system, therefore enhances its performance. Limiting oxygen index (LOI) is one of the most commonly used parameters to indicate the flammability of textiles and other polymeric materials. In this research, we investigated the correlation between LOI and phosphorus/nitrogen content on the cotton fabric treated with that durable flame‐retardant system. Phosphorus concentration on the fabric was analyzed by inductively coupled plasma atomic emission spectroscopy, whereas the nitrogen content was determined indirectly by measuring the carbonyl band intensity in the infrared spectra of the treated fabric. We developed a statistical model to predict LOI of the cotton fabric treated with FR and DMDHEU based on the phosphorus concentration and the intensity of carbonyl band of DMDHEU on cotton. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1885–1890, 2003
Preparation and characterization of poly(styrene butylacrylate) latex/nano‐ZnO nanocomposites
Authors: Xiong Mingna , Gu Guangxin , You Bo , Wu Limin
Published: September 2003

Poly(styrene butylacrylate) latex/nano‐ZnO composites were prepared by blending poly(styrene butylacrylate) latex with a water slurry of nano‐ZnO particles, and the effects of certain parameters, such as particle size, dispersant type, dispersing time and others, on the dispersibility, mechanical properties, ultraviolet (UV) shielding and near infrared (NIR) shielding were investigated with transmission electron microscopy (TEM), an Instron testing machine, dynamic mechanical analysis and ultraviolet‐visible‐near infrared (UV‐VIS‐NIR) spectrophotometry. TEM observation showed that dispersants with long chains are better than those with short chains at enhancing the dispersibility of nano‐ZnO particles in a matrix; extending dispersing time also improves the dispersibility of nano‐ZnO particles in a matrix. Instron tests showed that the nanocomposite polymers embedded with nano‐ZnO particles had much higher tensile strength than the corresponding composite polymers with micro‐ZnO particles. As the nano‐ZnO content increased, the temperature of glass transition (Tg) of the nanocomposite polymer embedded with 60 nm ZnO particles first increased then decreased, but 100 nm ZnO and micro‐ZnO particles seemed to have no influence on the Tg of the composite polymers. The better dispersibility of nano‐ZnO particles resulted in higher Tg values. Increasing nano‐ZnO content or dispersibility could enhance the UV shielding properties of the nanocomposite polymers, and 60 nm ZnO particles could more effectively shield UV rays than 100 nm ZnO particles. Micro‐ZnO particles basically had no effect on the UV absorbance of the composite polymers. A blue‐shift phenomenon was observed at 365 nm when nano‐ZnO particles were present in the nanocomposite polymers. NIR analysis indicated that as nano‐ZnO content increased, the NIR shielding of the nanocomposite polymers increased, but the NIR shielding properties seemed to be more influenced by particle size than by the nano‐effect. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1923–1931, 2003