47 research outputs found
Decolonizing the U.S. Health Care System: Undocumented and Disabled after ACA
The Affordable Care Act (ACA) explicitly denies newly arrived documented and undocumented immigrants health insurance coverage, effectively making them the largest remaining uninsured segment of the U.S. population. Using mixed qualitative methods, our original research illustrates the health consequences experienced by uninsured, disabled undocumented immigrants as they navigate what they describe as an apartheid health care system. Critiquing the notion of immigrants as “public charges” or burdens on the system, our qualitative analysis focuses on Houston Health Action, a community-based organization led by and for undocumented, low-income disabled immigrants in Houston, Texas. Engaging a critical migration and critical disabilities studies framework, we use this valuable case to highlight contemporary contradictions in health care and immigration legislation and the embodied consequences of the intersecting oppressions of race, ability, immigration status, and health care access
Lensing Bias in Cosmic Shear
Only galaxies bright enough and large enough to be unambiguously identified
and measured are included in galaxy surveys used to estimate cosmic shear. We
demonstrate that because gravitational lensing can scatter galaxies across the
brightness and size thresholds, cosmic shear experiments suffer from lensing
bias. We calculate the effect on the shear power spectrum and show that -
unless corrected for - it will lead analysts to cosmological parameters
estimates that are biased at the 2-3\sigma level in DETF Stage III experiments,
such as the Dark Energy Survey.Comment: 14 pages; 4 figures (this version). Accepted for publication in ApJ.
v2: incorporating referee's comments; v3: updated acknowledgment
Cosmological Constraints from the Large Scale Weak Lensing of SDSS MaxBCG Clusters
We derive constraints on the matter density \Om and the amplitude of matter
clustering \sig8 from measurements of large scale weak lensing (projected
separation R=5-30\hmpc) by clusters in the Sloan Digital Sky Survey MaxBCG
catalog. The weak lensing signal is proportional to the product of \Om and the
cluster-mass correlation function \xicm. With the relation between optical
richness and cluster mass constrained by the observed cluster number counts,
the predicted lensing signal increases with increasing \Om or \sig8, with mild
additional dependence on the assumed scatter between richness and mass. The
dependence of the signal on scale and richness partly breaks the degeneracies
among these parameters. We incorporate external priors on the richness-mass
scatter from comparisons to X-ray data and on the shape of the matter power
spectrum from galaxy clustering, and we test our adopted model for \xicm
against N-body simulations. Using a Bayesian approach with minimal restrictive
priors, we find \sig8(\Om/0.325)^{0.501}=0.828 +/- 0.049, with marginalized
constraints of \Om=0.325_{-0.067}^{+0.086} and \sig8=0.828_{-0.097}^{+0.111},
consistent with constraints from other MaxBCG studies that use weak lensing
measurements on small scales (R<=2\hmpc). The (\Om,\sig8) constraint is
consistent with and orthogonal to the one inferred from WMAP CMB data,
reflecting agreement with the structure growth predicted by GR for an LCDM
cosmological model. A joint constraint assuming LCDM yields \Om=0.298 +/- 0.020
and \sig8=0.831 +/- 0.020. Our cosmological parameter errors are dominated by
the statistical uncertainties of the large scale weak lensing measurements,
which should shrink sharply with current and future imaging surveys.Comment: 20 pages, 12 figures, MNRAS Submitted. For a brief video explaining
the key result of this paper, see http://www.youtube.com/user/OSUAstronomy,
or http://v.youku.com/v_show/id_XNDI3ODA3NzY4.html in countries where YouTube
is not accessibl
2015 Research & Innovation Day Program
A one day showcase of applied research, social innovation, scholarship projects and activities.https://first.fanshawec.ca/cri_cripublications/1002/thumbnail.jp
Situational factors shape moral judgements in the trolley dilemma in Eastern, Southern and Western countries in a culturally diverse sample
Analysis of shared heritability in common disorders of the brain
ience, this issue p. eaap8757 Structured Abstract INTRODUCTION Brain disorders may exhibit shared symptoms and substantial epidemiological comorbidity, inciting debate about their etiologic overlap. However, detailed study of phenotypes with different ages of onset, severity, and presentation poses a considerable challenge. Recently developed heritability methods allow us to accurately measure correlation of genome-wide common variant risk between two phenotypes from pools of different individuals and assess how connected they, or at least their genetic risks, are on the genomic level. We used genome-wide association data for 265,218 patients and 784,643 control participants, as well as 17 phenotypes from a total of 1,191,588 individuals, to quantify the degree of overlap for genetic risk factors of 25 common brain disorders. RATIONALE Over the past century, the classification of brain disorders has evolved to reflect the medical and scientific communities' assessments of the presumed root causes of clinical phenomena such as behavioral change, loss of motor function, or alterations of consciousness. Directly observable phenomena (such as the presence of emboli, protein tangles, or unusual electrical activity patterns) generally define and separate neurological disorders from psychiatric disorders. Understanding the genetic underpinnings and categorical distinctions for brain disorders and related phenotypes may inform the search for their biological mechanisms. RESULTS Common variant risk for psychiatric disorders was shown to correlate significantly, especially among attention deficit hyperactivity disorder (ADHD), bipolar disorder, major depressive disorder (MDD), and schizophrenia. By contrast, neurological disorders appear more distinct from one another and from the psychiatric disorders, except for migraine, which was significantly correlated to ADHD, MDD, and Tourette syndrome. We demonstrate that, in the general population, the personality trait neuroticism is significantly correlated with almost every psychiatric disorder and migraine. We also identify significant genetic sharing between disorders and early life cognitive measures (e.g., years of education and college attainment) in the general population, demonstrating positive correlation with several psychiatric disorders (e.g., anorexia nervosa and bipolar disorder) and negative correlation with several neurological phenotypes (e.g., Alzheimer's disease and ischemic stroke), even though the latter are considered to result from specific processes that occur later in life. Extensive simulations were also performed to inform how statistical power, diagnostic misclassification, and phenotypic heterogeneity influence genetic correlations. CONCLUSION The high degree of genetic correlation among many of the psychiatric disorders adds further evidence that their current clinical boundaries do not reflect distinct underlying pathogenic processes, at least on the genetic level. This suggests a deeply interconnected nature for psychiatric disorders, in contrast to neurological disorders, and underscores the need to refine psychiatric diagnostics. Genetically informed analyses may provide important "scaffolding" to support such restructuring of psychiatric nosology, which likely requires incorporating many levels of information. By contrast, we find limited evidence for widespread common genetic risk sharing among neurological disorders or across neurological and psychiatric disorders. We show that both psychiatric and neurological disorders have robust correlations with cognitive and personality measures. Further study is needed to evaluate whether overlapping genetic contributions to psychiatric pathology may influence treatment choices. Ultimately, such developments may pave the way toward reduced heterogeneity and improved diagnosis and treatment of psychiatric disorders
The genetic architecture of the human cerebral cortex
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder
Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders
Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyper-activity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.Peer reviewe
Subcortical volumes across the lifespan: Data from 18,605 healthy individuals aged 3–90 years
Age has a major effect on brain volume. However, the normative studies available are constrained by small sample sizes, restricted age coverage and significant methodological variability. These limitations introduce inconsistencies and may obscure or distort the lifespan trajectories of brain morphometry. In response, we capitalized on the resources of the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) Consortium to examine age‐related trajectories inferred from cross‐sectional measures of the ventricles, the basal ganglia (caudate, putamen, pallidum, and nucleus accumbens), the thalamus, hippocampus and amygdala using magnetic resonance imaging data obtained from 18,605 individuals aged 3–90 years. All subcortical structure volumes were at their maximum value early in life. The volume of the basal ganglia showed a monotonic negative association with age thereafter; there was no significant association between age and the volumes of the thalamus, amygdala and the hippocampus (with some degree of decline in thalamus) until the sixth decade of life after which they also showed a steep negative association with age. The lateral ventricles showed continuous enlargement throughout the lifespan. Age was positively associated with inter‐individual variability in the hippocampus and amygdala and the lateral ventricles. These results were robust to potential confounders and could be used to examine the functional significance of deviations from typical age‐related morphometric patterns
Cortical thickness across the lifespan: Data from 17,075 healthy individuals aged 3-90 years
Delineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown that robust estimates of the association between age and brain morphometry require large‐scale studies. In response, we used cross‐sectional data from 17,075 individuals aged 3–90 years from the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) Consortium to infer age‐related changes in cortical thickness. We used fractional polynomial (FP) regression to quantify the association between age and cortical thickness, and we computed normalized growth centiles using the parametric Lambda, Mu, and Sigma method. Interindividual variability was estimated using meta‐analysis and one‐way analysis of variance. For most regions, their highest cortical thickness value was observed in childhood. Age and cortical thickness showed a negative association; the slope was steeper up to the third decade of life and more gradual thereafter; notable exceptions to this general pattern were entorhinal, temporopolar, and anterior cingulate cortices. Interindividual variability was largest in temporal and frontal regions across the lifespan. Age and its FP combinations explained up to 59% variance in cortical thickness. These results may form the basis of further investigation on normative deviation in cortical thickness and its significance for behavioral and cognitive outcomes