107 research outputs found
A Geography of Cohabitation in the Americas, 1970-2010
In this chapter, we trace the geography of unmarried cohabitation in the Americas on an unprecedented geographical scale in family demography. We present the percentage of partnered women aged 25-29 in cohabitation across more than 19,000 local units of 39 countries, from Canada to Argentina, at two points in time, 2000 and 2010. The local geography is supplemented by a regional geography of cohabitation that covers five decades of data from 1960 to 2010. Our data derive primarily from the rich collection of census microdata amassed by the Centro Latinoamericano y Caribeño de Demografía (CELADE) of the United Nations and from the IPUMS-international collection of harmonized census microdata samples (Minnesota Population Center, Integrated public use microdata series, international: Version 6.3 [Machine-readable database]. University of Minnesota, Minneapolis, 2014). Our analyses unveil a substantial amount of spatial heterogeneity both within and across countries. Despite the spectacular rise in cohabitation, its regional patterning has remained relatively unchanged over the last decades, which points to the presence of geo-historical legacies in the present patterns of unmarried cohabitation
Relativistic quantum effects of Dirac particles simulated by ultracold atoms
Quantum simulation is a powerful tool to study a variety of problems in
physics, ranging from high-energy physics to condensed-matter physics. In this
article, we review the recent theoretical and experimental progress in quantum
simulation of Dirac equation with tunable parameters by using ultracold neutral
atoms trapped in optical lattices or subject to light-induced synthetic gauge
fields. The effective theories for the quasiparticles become relativistic under
certain conditions in these systems, making them ideal platforms for studying
the exotic relativistic effects. We focus on the realization of one, two, and
three dimensional Dirac equations as well as the detection of some relativistic
effects, including particularly the well-known Zitterbewegung effect and Klein
tunneling. The realization of quantum anomalous Hall effects is also briefly
discussed.Comment: 22 pages, review article in Frontiers of Physics: Proceedings on
Quantum Dynamics of Ultracold Atom
Altered Islet Composition and Disproportionate Loss of Large Islets in Patients with Type 2 Diabetes
Human islets exhibit distinct islet architecture with intermingled alpha- and beta-cells particularly in large islets. In this study, we quantitatively examined pathological changes of the pancreas in patients with type 2 diabetes (T2D). Specifically, we tested a hypothesis that changes in endocrine cell mass and composition are islet-size dependent. A large-scale analysis of cadaveric pancreatic sections from T2D patients (n = 12) and non-diabetic subjects (n = 14) was carried out combined with semi-automated analysis to quantify changes in islet architecture. The method provided the representative islet distribution in the whole pancreas section that allowed us to examine details of endocrine cell composition in individual islets. We observed a preferential loss of large islets (>60 µm in diameter) in T2D patients compared to non-diabetic subjects. Analysis of islet cell composition revealed that the beta-cell fraction in large islets was decreased in T2D patients. This change was accompanied by a reciprocal increase in alpha-cell fraction, however total alpha-cell area was decreased along with beta-cells in T2D. Delta-cell fraction and area remained unchanged. The computer-assisted quantification of morphological changes in islet structure minimizes sampling bias. Significant beta-cell loss was observed in large islets in T2D, in which alpha-cell ratio reciprocally increased. However, there was no alpha-cell expansion and the total alpha-cell area was also decreased. Changes in islet architecture were marked in large islets. Our method is widely applicable to various specimens using standard immunohistochemical analysis that may be particularly useful to study large animals including humans where large organ size precludes manual quantitation of organ morphology
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Genetic effects on gene expression across human tissues
Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of disease.Postprint (published version
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‘I deserve to be here’: minority ethnic students and their conditional belonging in UK higher education
In efforts to support students’ belonging in higher education, universities continue to cultivate and promote diversity and inclusion in their academic communities. Despite this endeavour, students from underrepresented backgrounds can still often encounter barriers to belonging at university. Existing research has identified multiple domains of student belonging in higher education, although there has been limited qualitative analysis of how belonging is experienced by minority ethnic students, especially at elite institutions. This paper draws on 72 in-depth interviews with minority ethnic STEM university students in the UK. Drawing on the sociological concept of conditional belonging, which is mostly used in migration studies, our findings indicate that students’ construction and negotiation of belonging can be ‘conditional’ and ‘conditioned’ based on their prior educational experiences, perceptions of being a minority within their institutional contexts and social and academic interaction with others. We argue that conditional belonging can shape how students participate, engage and develop belonging in higher education. We conclude with practical implications for learning and teaching that can foster a diverse and inclusive academic community for all
Examining the Incidence of Human Papillomavirus-Associated Head and Neck Cancers by Race and Ethnicity in the U.S., 1995–2005
Background: Head and neck cancer (HNC) incidence, mortality and survival rates vary by sex and race, with men and African Americans disproportionately affected. Risk factors for HNC include tobacco and alcohol exposure, with a recent implication of human papillomavirus (HPV) in the pathogenesis of HNC. This study describes the epidemiology of HNC in the United States, examining variation of rates by age, sex, race/ethnicity and potential HPV-association. Methods: We used the North American Association of Central Cancer Registries (NAACCR) Cancer in North America (CINA) Deluxe Analytic Data to analyze HNC incidence for 1995–2005 from forty population-based cancer registries. We calculated age-adjusted incidence rates and incidence trends using annual percent change by age, sex, race/ethnicity and HPVassociation. Results: Males and Non-Hispanic Blacks experienced greater HNC incidence compared to women and other race/ethnicity groupings. A significant overall increase in HNC incidence was observed among HPV-associated sites during 1995–2005, while non HPV-associated sites experienced a significant decline in HNC incidence. Overall, younger age groups, Non-Hispanic Whites and Hispanics experienced greater increases in incidence for HPV-associated sites, while HNC incidence declined for Non-Hispanic Blacks independent of HPV-association. In particular, for HPV-associated sites, HNC incidence for Non-Hispanic White males aged 45–54 increased at the greatest rate, with an APC of 6.28 % (p,0.05). Among non HPVassociated sites, Non-Hispanic Black males aged 0–44 years experienced the greatest reduction in incidence (APC, 28.17%
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Curriculum and assessment review November 2024: call for evidence. University of Reading collective submission
This report brings together the research and professional practice of colleagues from across the University of Reading to respond collectively to the Department for Education Call for Evidence
Medicago truncatula as a model for understanding plant interactions with other organisms, plant development and stress biology: past, present and future
Genetic effects on gene expression across human tissues
Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of disease
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