Racializing teenage pregnancy: 'culture' and 'tradition' in the South African scientific literature

The signifiers, 'race', 'culture' or 'ethnicity' are utilized in the teenage pregnancy literature (1) to highlight 'differences' in adolescent sexual and reproductive behaviour and (2) as explanatory tools. When 'white' teenagers are the focus of research, psychological explanations are usually invoked, whereas for 'black' teenagers, explanations are socio-cultural in nature. In this article, we explore how, through a process of racialization, the psychomedical literature on teenage pregnancy in South Africa contributes to the entrenchment of 'race', 'culture' and 'ethnicity' as fixed, 'natural' signifiers. We utilize Derrida's notion of différance , together with Phoenix and Woollett's adaptation - 'normalized absence/pathologized presence' - to indicate how 'black' people are cast as the Other, the pathologized presence which relies on the normalized absent trace, 'whiteness', for definition. We analyse how the notions of 'tradition' and 'culture' are deployed to sanitize or disguise the underlying racializing project. 'Black' is exoticized and rendered strange and thus open to scrutiny, monitoring and intervention. 'Culture' and 'tradition' appeal to the myth of origin, thus providing pseudohistorical explanations which essentialize and naturalize racialized collectivities.     

Comparison of articulate brachiopod nuclear and mitochondrial gene trees leads to a clade-based redefinition of protostomes (Protostomozoa) and deuterostomes (Deuterostomozoa)

Nuclear and mtDNA sequences from selected short-looped terebratuloid (terebratulacean) articulate brachiopods yield congruent and genetically independent phylogenetic reconstructions by parsimony, neighbour-joining and maximum likelihood methods, suggesting that both sources of data are reliable guides to brachiopod species phylogeny. The present-day genealogical relationships and geographical distributions of the tested terebratuloid brachiopods are consistent with a tethyan dispersal and subsequent radiation. Concordance of nuclear and mitochondrial gene phylogenies reinforces previous indications that articulate brachiopods, inarticulate brachiopods, phoronids and ectoprocts cluster with other organisms generally regarded as protostomes. Since ontogeny and morphology in brachiopods, ectoprocts and phoronids depart in important respects from those features supposedly diagnostic of protostomes, this demonstrates that the operational definition of protostomy by the usual ontological characters must be misleading or unreliable. New, molecular, operational definitions are proposed to replace the traditional criteria for the recognition of protostomes and deuterostomes, and the clade-based terms ''Protostomoza'' and ''Deuterostomozoa'' are proposed to replace the existing term ''Protostomia'' and ''Deuterostomia''.     

Evolution towards oscillation or stability in a predator–prey system

We studied a prey–predator system in which both species evolve. We discuss here the conditions that result in coevolution towards a stable equilibrium or towards oscillations. First, we show that a stable equilibrium or population oscillations with small amplitude is likely to occur if the prey''s (host''s) defence is effective when compared with the predator''s (parasite''s) attacking ability at equilibrium, whereas large-amplitude oscillations are likely if the predator''s (parasite''s) attacking ability exceeds the prey''s (host''s) defensive ability. Second, a stable equilibrium is more likely if the prey''s defensive trait evolves faster than the predator''s attack trait, whereas population oscillations are likely if the predator''s trait evolves faster than that of the prey. Third, when the adaptation rates of both species are similar, the amplitude of the fluctuations in their abundances is small when the adaptation rate is either very slow or very fast, but at an intermediate rate of adaptation the fluctuations have a large amplitude. We also show the case in which the prey''s abundance and trait fluctuate greatly, while those of the predator remain almost unchanged. Our results predict that populations and traits in host–parasite systems are more likely than those in prey–predator systems to show large-amplitude oscillations.     

Motion perception: from phi to omega.

When human observers view dynamic random noise, such as television ''snow'', through a curved or annular aperture, they experience a compelling illusion that the noise is moving smoothly and coherently around the curve (the ''omega effect''). In several series of experiments, we have investigated the conditions under which this effect occurs and the possible mechanisms that might cause it. We contrast the omega effect with ''phi motion'', seen when an object suddenly changes position. Our conclusions are that the visual scene is first segmented into objects before a coherent velocity is assigned to the texture on each object''s surface. The omega effect arises because there are motion mechanisms that deal specifically with object rotation and these interact with pattern mechanisms sensitive to curvature.     

Can male Eurasian jays disengage from their own current desire to feed the female what she wants?

Humans'' predictions of another person''s behaviour are regularly influenced by what they themselves might know or want. In a previous study, we found that male Eurasian jays (Garrulus glandarius) could cater for their female partner''s current desire when sharing food with her. Here, we tested the extent to which the males'' decisions are influenced by their own current desire. When the males'' and female''s desires matched, males correctly shared the food that was desired by both. When the female''s desire differed from their own, the males'' decisions were not entirely driven by their own desires, suggesting that males also took the female''s desire into account. Thus, the male jays'' decisions about their mates'' desires are partially biased by their own desire and might be based upon similar processes as those found in humans.     

Imitation of Body Movements Facilitated by Joint Attention through Eye Contact and Pointing in Japanese Monkey

Eye contact and pointing are typical gestures in order to direct another individual''s attention toward a target. We previously investigated on Japanese monkeys whether joint attention ability encouraged by eye contact and pointing was associated with the imitation of human''s actions. The monkeys with the joint attention skills showed the imitation of human''s actions. In the current study, we investigated on a monkey whether joint attention ability also facilitated the imitation of human body-movements. Results showed that the monkey being taught eye contact and pointing showed the imitation of human body-movements. These results suggest that the monkeys have basic potential for following another individual''s motion, and that what imitation expresses depends on where the monkeys are paying attention. Thus, eye contact and pointing are suitable for directing the monkey''s attention toward the human.     

Unexplained left ventricular hypertrophy: consider a diagnosis of Fabry's disease

Lysosomal storage disorders are a group of disorders characterised by the deficiency of a specific lysosomal hydrolase. These diseases are rare, with only a few hundred patients in the Netherlands. Fabry''s disease, an X-linked lysosomal storage disorder, is caused by a deficiency of the lysosomal enzyme α-galactosidase A which results in, among other things, left ventricular hypertrophy, renal failure and cerebrovascular events. Patients with Fabry''s disease, especially males, have a decreased life expectancy. Recent studies have shown that Fabry''s disease may be much more common among patients with left ventricular hypertrophy (LVH) than previously thought. Up to 7% of male patients with left ventricular hypertrophy and up to 12% of female patients with unexplained LVH were found to suffer from Fabry''s disease. Thus, Fabry''s disease should be considered in patients with unexplained LVH. This case report summarises the main features of the disease. In addition recent developments concerning prevalence, diagnosis and the current available treatments are discussed and an algorithm on who and how to screen for Fabry''s disease is presented.     

Sperm competition games: a prospective analysis of risk assessment.

We develop the logic of assessment of sperm competition risk by individual males where the mechanism of sperm competition follows a ''loaded raffle'' (first and second inseminates of a female have unequal prospects). Male roles (first or second to mate) are determined randomly. In model 1, males have no information about the risk associated with individual females and ejaculation strategy depends only on the probability, q, that females mate twice. Evolutionarily stable strategy (ESS) ejaculate expenditure increases linearly from zero with q, and reduces with increasing inequality between ejaculates, though the direction of the loading (which role is favoured) is unimportant. In model 2, males have perfect information and can identify each of three risk states: females that will (1) mate just once (''no risk''), (2) mate twice but have not yet mated (''future risk''), and (3) mate twice and have already mated (''past risk''). The ESS is to ejaculate minimally with ''no risk'' females, and to expand equally with ''past'' and ''future'' risk females; the direction of the competitive loading is again unimportant. Expenditure again increases with risk, but is now non-zero at extremely low risk. Model 3 examines three cases of partial information where males can identify only one of the three risk states and cannot distinguish between the other two: they therefore have just two information sets or ''contexts''. Expenditure in both contexts typically rises non-linearly from zero with q, but (whatever the loading direction) expenditure is higher in the context with higher risk (e.g. if contexts are ''mated'' and ''virgin'', males spend more with mated females). However, in highly loaded raffles, sperm expenditure can decrease over part of the range of risk. Also, the direction of the loading now affects expenditure. Biological evidence for the predictions of the models is summarized and discussed.     

NON-INFECTIOUS INFLAMMATORY AND NEOPLASTIC DISORDERS OF THE MALE GENITALIA

The cutaneous manifestations of the male external genitalia are difficult to diagnose. They may be associated with systemic disease (Reiter''s disease, psoriatic arthritis, angiokeratoma corporis diffusum). In dealing with a lesion of this area that does not heal, adequate biopsy is advisable to rule out malignant disease (Bowen''s disease, melanoma, Kaposi''s sarcoma, Paget''s disease, erythroplasia).     

Human Direct Actions May Alter Animal Welfare,a Study on Horses (Equus caballus)

Background

Back pain is the cause of bad welfare in humans and animals. Although vertebral problems are regularly reported on riding horses, these problems are not always identified nor noticed enough to prevent these horses to be used for work.

Methodology/Principal Findings

Nineteen horses from two riding centres were submitted to chiropractic examinations performed by an experienced chiropractor and both horses'' and riders'' postures were observed during a riding lesson. The results show that 74% of horses were severely affected by vertebral problems, while only 26% were mildly or not affected. The degree of vertebral problems identified at rest was statistically correlated with horses'' attitudes at work (neck height and curve), and horses'' attitudes at work were clearly correlated with riders'' positions. Clear differences appeared between schools concerning both riders'' and horses'' postures, and the analysis of the teachers'' speech content and duration highlighted differences in the attention devoted to the riders'' position.

Conclusion/Significance

These findings are to our knowledge the first to underline the impact of riding on horses'' back problems and the importance of teaching proper balance to beginner riders in order to increase animals'' welfare.     

Autistic autobiography

Autism narratives are not just stories or histories, describing a given reality. They are creating the language in which to describe the experience of autism, and hence helping to forge the concepts in which to think autism. This paper focuses on a series of autobiographies that began with Grandin''s Emergence. These are often said to show us autism from the ‘inside’. The paper proposes that instead they are developing ways to describe experience for which there is little pre-existing language. Wittgenstein has many well-known aphorisms about how we understand other people directly, without inference. They condense what he had found in Wolfgang Köhler''s Gestalt Psychology. These phenomena of direct understanding what other people are doing are, Köhler wrote, ‘the common property and practice of mankind''. They are not the common property and practice of people with autism. Ordinary language is rich in age-old ways to describe what others are thinking, feeling and so forth. Köhler''s phenomena are the bedrock on which such language rests. There is no such discourse for autism, because Köhler''s phenomena are absent. But a new discourse is being made up right now, i.e. ways of talking for which the autobiographies serve as working prototypes.     

A behavioral test of accepting benefits that cost others: associations with conduct problems and callous-unemotionality

Background

Youth with conduct problems (CP) often make decisions which value self-interest over the interests of others. Self-benefiting behavior despite loss to others is especially common among youth with CP and callous-unemotional traits (CU). Such behavioral tendencies are generally measured using self- or observer-report. We are unaware of attempts to measure this tendency with a behavioral paradigm.

Methods/Principal Findings

In our AlAn''s (altruism-antisocial) game a computer program presents subjects with a series of offers in which they will receive money but a planned actual charity donation will be reduced; subjects decide to accept or reject each offer. We tested (1) whether adolescent patients with CP (n = 20) compared with adolescent controls (n = 19) differed on AlAn''s game outcomes, (2) whether youths with CP and CU differed significantly from controls without CP or CU, and (3) whether AlAn''s game outcomes correlated significantly with CP and separately, CU severity. Patients with CP and CU compared with controls without these problems took significantly more money for themselves and left significantly less money in the charity donation; AlAn''s game outcomes were significantly correlated with CU, but not CP.

Conclusions/Significance

In the AlAn''s game adolescents with conduct problems and CU traits, compared with controls without CP/CU, are disposed to benefit themselves while costing others even in a novel situation, devoid of peer influences, where anonymity is assured, reciprocity or retribution are impossible, intoxication is absent and when the “other” to be harmed is considered beneficent. AlAn''s game outcomes are associated with measures of CU. Results suggest that the AlAn''s game provides an objective means of capturing information about CU traits. The AlAn''s game, which was designed for future use in the MRI environment, may be used in studies attempting to identify the neural correlates of self-benefiting decision-making.     

ON THE QUANTITY OF ELECTRICITY AND THE ENERGY IN ELECTRICAL STIMULATION

Weiss''s and Hoorweg''s laws are discussed with respect to the dynamics of the excitatory process. The former is shown to have a simple basis which is inadequate, however, because it implies a constant rate of subsidence of the state of excitation. Hoorweg''s law does not follow logically from the same basis so the two laws do not represent the same excitatory mechanism. Experimental data do not give minimal energies at 2 rheobases as predicted by each law. The experimental minima with direct currents are at 1.5 or more rheobases, while with condenser stimuli they are from 2.5 to 3.0 rheobases. These minima conform to the predictions of the writer''s equations which give the direct current minima as variable with a lower limit at 1.5 rheobases and the condenser minima as constant at e = 2.718 rheobases. The reasons for these differences are discussed and it is concluded that considerations of the quantity of electricity and the energy, per se, do not lead to any simple concepts with regard to the excitatory mechanism. The existing quantity and energy relations are, however, easily correlated in terms of the dynamics of the excitatory mechanism.     

An Endothelial Planar Cell Model for Imaging Immunological Synapse Dynamics

Adaptive immunity is regulated by dynamic interactions between T cells and antigen presenting cells (''APCs'') referred to as ''immunological synapses''. Within these intimate cell-cell interfaces discrete sub-cellular clusters of MHC/Ag-TCR, F-actin, adhesion and signaling molecules form and remodel rapidly. These dynamics are thought to be critical determinants of both the efficiency and quality of the immune responses that develop and therefore of protective versus pathologic immunity. Current understanding of immunological synapses with physiologic APCs is limited by the inadequacy of the obtainable imaging resolution. Though artificial substrate models (e.g., planar lipid bilayers) offer excellent resolution and have been extremely valuable tools, they are inherently non-physiologic and oversimplified. Vascular and lymphatic endothelial cells have emerged as an important peripheral tissue (or stromal) compartment of ''semi-professional APCs''. These APCs (which express most of the molecular machinery of professional APCs) have the unique feature of forming virtually planar cell surface and are readily transfectable (e.g., with fluorescent protein reporters). Herein a basic approach to implement endothelial cells as a novel and physiologic ''planar cellular APC model'' for improved imaging and interrogation of fundamental antigenic signaling processes will be described.     

The terminology problem for T cells: a discussion paper

The school of thought that owes allegiance to Ludwig Wittgenstein teaches that language conditions perceptions. When we use the term ''cytotoxic T lymphocyte'' or ''helper T cell'' we tend to orientate our own thinking processes, and those of listeners or readers, down particular paths. Part of the problem is that we are often describing cell populations by functions that may either be a property of only a proportion of those that are being assayed, or are simply inferred from the expression of various cell-surface markers. The consequence can be a measure of confusion that might be avoided if we could communicate with greater clarity. Is it possible to achieve a better terminology that will be accepted generally? The following are some examples of why there may be some value in thinking about this.     

喜盐鸢尾花色形成关键基因的克隆及表达分析

喜盐鸢尾(Iris halophila Pall.)及其变种蓝花喜盐鸢尾(I.halophila Pall.var.sogdiana(Bung)Grubov)因耐盐碱及其多种花色而具有盐碱地园艺开发价值。本文根据喜盐鸢尾内轮花被转录组测序结果,利用基因特异性引物从这2种植物中分别克隆了编码查尔酮合成酶(CHS)、查尔酮异构酶(CHI)、类黄酮-3',5'-羟基化酶类(F3'5'H-like)等基因的部分片段,并对它们在内轮花被中的表达水平进行实时定量PCR分析。序列分析结果确认在喜盐鸢尾中所克隆的CHS(311 bp)、CHI(457 bp)、F3'5'H-like(496 bp)3个基因(部分)未见文献报道与NCBI等数据库记录。其中F3'5'H-like基因与经典的属于细胞色素P450CYP75A亚家族的F3'5'H不同,而与万带兰的F3'5'H-like同属于CYP76AB亚家族,为一类新的蓝花相关基因。实时定量PCR表达分析结果表明,与黄花的喜盐鸢尾相比,蓝花喜盐鸢尾中CHS与F3'5'H-like显著上调表达,可能是其花色不同于喜盐鸢尾的主要原因。     

Health expectancy and the problem of substitute morbidity.

During the past century, the developed world has not only witnessed a dramatic increase in life expectancy (ageing), but also a concomitant rise in chronic disease and disability. Consequently, the tension between ''living longer'' on the one hand and health-related ''quality of life'' on the other has become an increasingly important health policy problem. The paper deals with two consequences of this so-called epidemiological transition in population health. The first one concerns the question of how--given the impressive changes--population health can be measured in an adequate and policy relevant present-day fashion. The second one is the so-called phenomenon of ''substitute morbidity and mortality'': more and more acute fatal diseases are replaced by non-fatal delayed degenerative diseases like dementia and arthritis. How the phenomenon of substitute morbidity and mortality affects the development of population health is illustrated with the epidemiological transitions, worldwide shifts in the main causes of death, assumptions used in models, adverse consequences of medical technologies and some results from intervention trials. Substitute morbidity and mortality may thwart our disease-specific expectations of interventions and asks for a shift to a ''total population health'' perspective when judging potential health gains of interventions. Better understanding of the dynamics that underly the changes in population health is necessary. Implications for data collections are more emphasis on morbidity data and their relation with mortality, more longitudinal studies, stricter requirements for intervention trials and more use of modelling as a tool. A final recommendation is the promotion of integrative measures of population health. For the latter several results are presented suggesting that, although the amount of morbidity and disability is growing with an increasing life expectancy, this is mild unhealthiness in particular. This finding supports the ''dynamic equilibrium'' theory. In absolute numbers, however, the burden of disease will continue to increase with further ageing of the population.     

基于益生菌治疗帕金森病的研究进展

帕金森病是常见的神经退行性疾病,其发病原因至今尚未明确,目前的治疗方法价格昂贵、效果差且副作用大。帕金森病患者常见胃肠道功能障碍,帕金森病和肠道菌群之间的关联已得到实验证实,患者有望通过益生菌改善肠道菌群达到治疗的目的。工程益生菌的出现使得人们可以按照自己的意愿改造益生菌,提高其稳定性和靶向性,展现出其特有的应用潜力。本文将从益生菌治疗帕金森病的研究现状出发,阐述益生菌治疗帕金森病的可能机制,进一步分析工程益生菌治疗帕金森病的可行性,为该疾病的安全治疗提供新的思路。