168 research outputs found
The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000A (III): Cosmological Implications
(Abridged) We have used HST WFPC2 and ground-based spectroscopy to measure
the integrated extragalactic background light (EBL) at optical wavelengths. We
have also computed the integrated light from individual galaxy counts in the
images used to measure the EBL and in the Hubble Deep Field. We find that the
flux in galaxies as measured by standard galaxy photometry methods has
generally been underestimated by about 50%. Further, we find that the total
flux in individually detected galaxies is a factor of 2 to 3 less than the EBL
at 3000--8000A. We show that a significant fraction of the EBL may come from
normal galaxies at z<4, which are simply undetectable as a result of
K-corrections and cosmological surface brightness dimming. This is consistent
with recent redshift surveys at z<4. In the context of some simple models, we
discuss the constraints placed by the EBL on the evolution of the luminosity
density at z>1. Based on our optical EBL and published UV and IR EBL
measurements, we estimate that the total EBL from 0.1--1000 microns is 100+/-20
nW/m^2/sr. If the total EBL were produced entirely by stellar nucleosynthesis,
then we estimate that the total baryonic mass processed through stars is
Omega_* = 0.0062 (+/- 0.0022) h^{-2}, which corresponds to 0.33+/-0.12 Omega_B
for currently favored values of the baryon density. This estimate is smaller by
roughly 7% if 7 h_{0.7} nW/m^2/sr of the total EBL comes from accretion onto
central black holes. This estimate of Omega_* suggests that the universe has
been enriched to a total metal mass of 0.21(+/-0.13) Z_sun Omega_B. Our
estimate is consistent with other measurements of the cumulative metal mass
fraction of stars, stellar remnants, and the intracluster medium of galaxy
clusters in the local universe.Comment: Accepted for publication in ApJ, 20 pages using emulateapj.sty,
version with higher resolution figures available at
http://www.astro.lsa.umich.edu/~rab/publications.html or at
http://nedwww.ipac.caltech.edu/level5/Sept01/Bernstein3/frames.htm
Recommended from our members
EM-mosaic detects mosaic point mutations that contribute to congenital heart disease.
BackgroundThe contribution of somatic mosaicism, or genetic mutations arising after oocyte fertilization, to congenital heart disease (CHD) is not well understood. Further, the relationship between mosaicism in blood and cardiovascular tissue has not been determined.MethodsWe developed a new computational method, EM-mosaic (Expectation-Maximization-based detection of mosaicism), to analyze mosaicism in exome sequences derived primarily from blood DNA of 2530 CHD proband-parent trios. To optimize this method, we measured mosaic detection power as a function of sequencing depth. In parallel, we analyzed our cohort using MosaicHunter, a Bayesian genotyping algorithm-based mosaic detection tool, and compared the two methods. The accuracy of these mosaic variant detection algorithms was assessed using an independent resequencing method. We then applied both methods to detect mosaicism in cardiac tissue-derived exome sequences of 66 participants for which matched blood and heart tissue was available.ResultsEM-mosaic detected 326 mosaic mutations in blood and/or cardiac tissue DNA. Of the 309 detected in blood DNA, 85/97 (88%) tested were independently confirmed, while 7/17 (41%) candidates of 17 detected in cardiac tissue were confirmed. MosaicHunter detected an additional 64 mosaics, of which 23/46 (50%) among 58 candidates from blood and 4/6 (67%) of 6 candidates from cardiac tissue confirmed. Twenty-five mosaic variants altered CHD-risk genes, affecting 1% of our cohort. Of these 25, 22/22 candidates tested were confirmed. Variants predicted as damaging had higher variant allele fraction than benign variants, suggesting a role in CHD. The estimated true frequency of mosaic variants above 10% mosaicism was 0.14/person in blood and 0.21/person in cardiac tissue. Analysis of 66 individuals with matched cardiac tissue available revealed both tissue-specific and shared mosaicism, with shared mosaics generally having higher allele fraction.ConclusionsWe estimate that ~ 1% of CHD probands have a mosaic variant detectable in blood that could contribute to cardiac malformations, particularly those damaging variants with relatively higher allele fraction. Although blood is a readily available DNA source, cardiac tissues analyzed contributed ~ 5% of somatic mosaic variants identified, indicating the value of tissue mosaicism analyses
Veterans and Agent Orange: Update 11 (2018) (2018)
Contents
ACRONYMS AND ABBREVIATIONS xvii
SUMMARY 1
1 INTRODUCTION 17
Previous Veterans and Agent Orange Reports, 18
Charge to the Committee, 19
Information Gathering, 20
Organization of the Report, 21
2 BACKGROUND 25
The Current Population of Vietnam Veterans,25
Military Use of Herbicides in Vietnam, 27
Exposure of Different Groups of Vietnam Veterans, 30
Characterizing Exposure, 38
Determining Increased Risk in Vietnam Veterans, 4
The Erotic and the Vulgar: Visual Culture and Organized Labor's Critique of U.S. Hegemony in Occupied Japan
This essay engages the colonial legacy of postwar Japan by arguing that the political cartoons produced as part of the postwar Japanese labor movement’s critique of U.S. cultural hegemony illustrate how gendered discourses underpinned,
and sometimes undermined, the ideologies formally represented by visual artists and the organizations that funded them. A significant component of organized
labor’s propaganda rested on a corpus of visual media that depicted women as icons of Japanese national culture. Japan’s most militant labor unions were propagating anti-imperialist discourses that invoked an engendered/endangered nation that accentuated the importance of union roles for men by subordinating, then eliminating, union roles for women
Recommended from our members
The first 20 months of the COVID-19 pandemic: Mortality, intubation and ICU rates among 104,590 patients hospitalized at 21 United States health systems
Main objective: There is limited information on how patient outcomes have changed during the COVID-19 pandemic. This study characterizes changes in mortality, intubation, and ICU admission rates during the first 20 months of the pandemic. Study design and methods: University of Wisconsin researchers collected and harmonized electronic health record data from 1.1 million COVID-19 patients across 21 United States health systems from February 2020 through September 2021. The analysis comprised data from 104,590 adult hospitalized COVID-19 patients. Inclusion criteria for the analysis were: (1) age 18 years or older; (2) COVID-19 ICD-10 diagnosis during hospitalization and/or a positive COVID-19 PCR test in a 14-day window (+/- 7 days of hospital admission); and (3) health system contact prior to COVID-19 hospitalization. Outcomes assessed were: (1) mortality (primary), (2) endotracheal intubation, and (3) ICU admission. Results and significance: The 104,590 hospitalized participants had a mean age of 61.7 years and were 50.4% female, 24% Black, and 56.8% White. Overall risk-standardized mortality (adjusted for age, sex, race, ethnicity, body mass index, insurance status and medical comorbidities) declined from 16% of hospitalized COVID-19 patients (95% CI: 16% to 17%) early in the pandemic (February-April 2020) to 9% (CI: 9% to 10%) later (July-September 2021). Among subpopulations, males (vs. females), those on Medicare (vs. those on commercial insurance), the severely obese (vs. normal weight), and those aged 60 and older (vs. younger individuals) had especially high mortality rates both early and late in the pandemic. ICU admission and intubation rates also declined across these 20 months. Conclusions: Mortality, intubation, and ICU admission rates improved markedly over the first 20 months of the pandemic among adult hospitalized COVID-19 patients although gains varied by subpopulation. These data provide important information on the course of COVID-19 and identify hospitalized patient groups at heightened risk for negative outcomes. Trial registration: ClinicalTrials.gov Identifier: NCT04506528 (https://clinicaltrials.gov/ct2/show/NCT04506528).</p
Dietary carbohydrate restriction as the first approach in diabetes management:Critical review and evidence base
AbstractThe inability of current recommendations to control the epidemic of diabetes, the specific failure of the prevailing low-fat diets to improve obesity, cardiovascular risk, or general health and the persistent reports of some serious side effects of commonly prescribed diabetic medications, in combination with the continued success of low-carbohydrate diets in the treatment of diabetes and metabolic syndrome without significant side effects, point to the need for a reappraisal of dietary guidelines. The benefits of carbohydrate restriction in diabetes are immediate and well documented. Concerns about the efficacy and safety are long term and conjectural rather than data driven. Dietary carbohydrate restriction reliably reduces high blood glucose, does not require weight loss (although is still best for weight loss), and leads to the reduction or elimination of medication. It has never shown side effects comparable with those seen in many drugs. Here we present 12 points of evidence supporting the use of low-carbohydrate diets as the first approach to treating type 2 diabetes and as the most effective adjunct to pharmacology in type 1. They represent the best-documented, least controversial results. The insistence on long-term randomized controlled trials as the only kind of data that will be accepted is without precedent in science. The seriousness of diabetes requires that we evaluate all of the evidence that is available. The 12 points are sufficiently compelling that we feel that the burden of proof rests with those who are opposed
Effect of aspirin on cancer incidence and mortality in older adults.
BACKGROUND: ASPirin in Reducing Events in the Elderly (ASPREE), a randomized double-blind placebo-controlled trial (RCT) of daily low-dose aspirin (100 mg) in older adults, showed an increase in all-cause mortality, primarily due to cancer. In contrast prior RCTs, mainly involving younger individuals, demonstrated a delayed cancer benefit with aspirin. We now report a detailed analysis of cancer incidence and mortality. METHODS: 19,114 Australian and U.S. community-dwelling participants aged 70+ years (U.S. minorities 65+ years) without cardiovascular disease, dementia or physical disability were randomized and followed for a median of 4.7 years. Fatal and non-fatal cancer events, a prespecified secondary endpoint, were adjudicated based on clinical records. RESULTS: 981 cancer events occurred in the aspirin and 952 in the placebo groups. There was no statistically significant difference between groups for all incident cancers (HR = 1.04, 95% CI = 0.95 to 1.14), hematological cancer (HR = 0.98, 95% CI = 0.73 to 1.30), or all solid cancers (HR = 1.05, 95% CI = 0.95 to 1.15), including by specific tumor type. However, aspirin was associated with an increased risk of incident cancer that had metastasized (HR = 1.19, 95% CI = 1.00 to 1.43) or was stage 4 at diagnosis (HR = 1.22, 95% CI = 1.02 to 1.45), and with higher risk of death for cancers that presented at stages 3 (HR = 2.11, 95% CI = 1.03 to 4.33) or 4 (HR = 1.31, 95% CI = 1.04 to 1.64). CONCLUSIONS: In older adults, aspirin treatment had an adverse effect on later stages of cancer evolution. These findings suggest that in older persons, aspirin may accelerate the progression of cancer and thus, suggest caution with its use in this age group
Better health while you wait: A controlled trial of a computer-based intervention for screening and health promotion in the emergency department
Histone H2A Mono-Ubiquitination Is a Crucial Step to Mediate PRC1-Dependent Repression of Developmental Genes to Maintain ES Cell Identity
Two distinct Polycomb complexes, PRC1 and PRC2, collaborate to maintain epigenetic repression of key developmental loci in embryonic stem cells (ESCs). PRC1 and PRC2 have histone modifying activities, catalyzing mono-ubiquitination of histone H2A (H2AK119u1) and trimethylation of H3 lysine 27 (H3K27me3), respectively. Compared to H3K27me3, localization and the role of H2AK119u1 are not fully understood in ESCs. Here we present genome-wide H2AK119u1 maps in ESCs and identify a group of genes at which H2AK119u1 is deposited in a Ring1-dependent manner. These genes are a distinctive subset of genes with H3K27me3 enrichment and are the central targets of Polycomb silencing that are required to maintain ESC identity. We further show that the H2A ubiquitination activity of PRC1 is dispensable for its target binding and its activity to compact chromatin at Hox loci, but is indispensable for efficient repression of target genes and thereby ESC maintenance. These data demonstrate that multiple effector mechanisms including H2A ubiquitination and chromatin compaction combine to mediate PRC1-dependent repression of genes that are crucial for the maintenance of ESC identity. Utilization of these diverse effector mechanisms might provide a means to maintain a repressive state that is robust yet highly responsive to developmental cues during ES cell self-renewal and differentiation
Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.
The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD
- …