Images of the body: Lay and biomedical views of the reproductive system in Britain and Brazil

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis presents an anthropological study of ordinary people's views about the body in general and the reproductive system in particular, based on two case studies carried out in Britain and in Brazil. I discuss the meanings of lay and biomedical images of the body and identify the ways the researched groups reinterpret the biomedical view of the body anatomy and physiology. Through the analysis of ethnographic material on time, space and domestic organisation in four shantytown groups in Porto Alegre, Brazil and in three different groups in London, UK, I point out the dwelling peculiarities of the different groups and suggest there is a relationship between embodied experiences of time/space and knowledge of the reproductive system. These arguments lead to a more general phenomenologically theorised view of gendered and status-framed bodies, consequently situating this work in the interface of Medical Anthropology and a more general socio-cultural Anthropology.This study is funded by the CNPQ - Conselho Nacional de Desenvolvimento Cientifico e Tecnologico

The transcription factor Foxo1 controls germinal center B cell proliferation in response to T cell help

Germinal center (GC) B cells cycle between two states, the light zone (LZ) and the dark zone (DZ), and in the latter they proliferate and hypermutate their immunoglobulin genes. How this functional transition takes place is still controversial. In this study, we demonstrate that ablation of Foxo1 after GC development led to the loss of the DZ GC B cells and disruption of the GC architecture, which is consistent with recent studies. Mechanistically, even upon provision of adequate T cell help, Foxo1-deficient GC B cells showed less proliferative expansion than controls. Moreover, we found that the transcription factor BATF was transiently induced in LZ GC B cells in a Foxo1-dependent manner and that deletion of BATF similarly led to GC disruption. Thus, our results are consistent with a model where the switch from the LZ to the DZ is triggered after receipt of T cell help, and suggest that Foxo1-mediated BATF up-regulation is at least partly involved in this switch

New opportunities for photon storage and detection: an exploration of a high-efficiency optical quantum memory and the quantum capabilities of the human eye

The field of quantum information has grown in recent years, due to tremendous technological advancements toward quantum networking and quantum computation. Nevertheless, there is still a great need for creative research that explores possibilities for new capabilities. Particularly, we look towards quantum optics research to develop new ways of manipulating and detecting photons. Here, we discuss our efforts toward developing two separate quantum optics experiments that can provide great insight into the development of quantum devices. We begin by discussing our work to investigate the lower threshold of human vision and the eye's potential as a single-photon detector, using a custom-built single-photon source, and a novel two-alternative forced-choice experimental design. Our preliminary findings show promising data that support previous results found from a similar experiment using a somewhat different approach. We then discuss our second project, where we have developed a robust reconfigurable optical delay line quantum memory that compares favorably with competing methods. Our memory is capable of photon storage with an unprecedentedly high time-bandwidth product, high free-space transmission over the range of 10 $\mu$s, and high fidelity. These attributes, plus the memory's capability for multi-mode storage, make this system a strong candidate for a critical component in the large-scale heterogeneous quantum networks we hope to see developed in the next ten years

Ferromagnetic relaxation by magnon-induced currents

A theory for calculating spin wave relaxation times based on the magnon-electron interaction is developed. The theory incorporates a thin film geometry and is valid for a large range of magnon frequencies and wave vectors. For high conductivity metals such as permalloy, the wave vector dependent damping constant approaches values as high as 0.2, showing the large magnitude of the effect, and can dominate experimentally observed relaxation.Comment: 5 pages, 4 figure

Think coalitions in contemplrary Argentine

Este artículo analiza el fracaso de los procesos de conversión de las coaliciones electorales en coaliciones de gobierno, y la difícil institucionalización de las coaliciones en Argentina, desde una perspectiva de estudio interesada en destacar la articulación entre factores históricos de larga duración y transformaciones políticas recientes. Desde este ángulo de preocupaciones, se sostiene que las coaliciones fueron más un instrumento de construcción de hegemonía en clave de gobierno de “unidad nacional” que un sistema de pactos inspirado en el principio del poder compartido.This article analyzes the failure of the processes of conversion of the electoral coalitions in coalitions of government, and the difficult institutionalization of the coalitions in Argentina, from a perspective of study interested in emphasizing the joint between historical factors of long duration and political recent transformations. From this angle of worries, is held that the coalitions were more an instrument of construction of hegemony in key of government of “national unit” that a system of agreements inspired by the beginning of the shared power.Fil: Tcach, Cesar Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Estudios Sobre Cultura y Sociedad. Universidad Nacional de Córdoba. Centro de Investigaciones y Estudios Sobre Cultura y Sociedad; Argentin

Using genotype abundance to improve phylogenetic inference

Modern biological techniques enable very dense genetic sampling of unfolding evolutionary histories, and thus frequently sample some genotypes multiple times. This motivates strategies to incorporate genotype abundance information in phylogenetic inference. In this paper, we synthesize a stochastic process model with standard sequence-based phylogenetic optimality, and show that tree estimation is substantially improved by doing so. Our method is validated with extensive simulations and an experimental single-cell lineage tracing study of germinal center B cell receptor affinity maturation

Socioeconomic and racial/ethnic differentials of C-reactive protein levels: a systematic review of population-based studies

Background:Socioeconomic and racial/ethnic factors strongly influence cardiovascular disease outcomes and risk factors. C-reactive protein (CRP), a non-specific marker of inflammation, is associated with cardiovascular risk, and knowledge about its distribution in the population may help direct preventive efforts. A systematic review was undertaken to critically assess CRP levels according to socioeconomic and racial/ethnic factors. Methods:Medline was searched through December 2006 for population-based studies examining CRP levels among adults with respect to indicators of socioeconomic position (SEP) and/or race/ethnicity. Bibliographies from located studies were scanned and 26 experts in the field were contacted for unpublished work. Results:Thirty-two relevant articles were located. Cross-sectional (n = 20) and cohort studies (n = 11) were included, as was the control group of one trial. CRP levels were examined with respect to SEP and race/ethnicity in 25 and 15 analyses, respectively. Of 20 studies that were unadjusted or adjusted for demographic variables, 19 found inverse associations between CRP levels and SEP. Of 15 similar studies, 14 found differences between racial/ethnic groups such that whites had the lowest while blacks, Hispanics and South Asians had the highest CRP levels. Most studies also included adjustment for potential mediating variables in the causal chain between SEP or race/ethnicity and CRP. Most of these studies showed attenuated but still significant associations. Conclusion: Increasing poverty and non-white race was associated with elevated CRP levels among adults. Most analyses in the literature are underestimating the true effects of racial/ethnic and socioeconomic factors due to adjustment for mediating factors

Do muscle strength imbalances and low flexibility levels lead to low back pain? A brief review

Chronic low back pain (CLBP) has been related to hips, trunk and spine strength imbalances and/or low flexibility levels. However, it is not clear if the assessment and normalization of these variables are effective for prevention of low back pain (LBP) episodes and rehabilitation of patients with CLBP. This brief review explored studies that have associated hip, trunk and spine strength imbalances and/or low flexibility levels to LBP episodes or CLBP condition. Fourteen studies were selected by accessing PubMed and Google Scholar databases. Collectively, the selected studies demonstrate that trunk eccentric/concentric and flexion/extension strength imbalances may be associated with CLBP or LBP episodes. However, the literature fails to demonstrate any clear relationship between hip strength imbalances or low levels of spine flexibility with CLBP or LBP episodes. In addition, there is no direct evidence to support the idea that the normalization of these variables due to resistance and flexibility training leads to pain reduction and functionality improvements in subjects with CLBP. Although further investigation is needed, the lack of a clear direct association between hip strength imbalances or spine low flexibility levels to CLBP or LBP episodes may demonstrate that these variables may have very low effect within the complexity of these conditions

Exchange coupled perpendicular media

The potential of exchange spring bilayers and graded media is reviewed. An analytical model for the optimization of graded media gives an optimal value of the magnetic polarization of Js = 0.8 T. The optimum design allows for thermally stable grains with grain diameters in the order of 3.3 nm, which supports ultra high density up to 5 to 10 Tbit per inch2. The switching field distribution is significantly reduced in bilayer media and graded media compared to single phase media. For the graded media the switching field distribution is reduced by about a factor of two. For bilayer media the minimum switching field distribution is obtained for soft layer anisotropies about one fifth of the hard layer anisotropy. The influence of precessional switching on the reversal time and the reversal field is investigated in detail for magnetic bilayers. Exchange spring bilayers can be reversed with field pulses of 20 ps.Comment: submitted to JMMM, 'Current Perspectives; Perpendicular recording