Low-frequency ocean bottom pressure variations in the North Pacific in response to time-variable surface winds

One decade of time-variable gravity field observations from the GRACE satellite mission reveals low-frequency ocean bottom pressure (OBP) variability of up to 2.5 hPa centered at the northern flank of the subtropical gyre in the North Pacific. From a 145 year-long simulation with a coupled chemistry climate model, OBP variability is found to be related to the prevailing atmospheric sea-level pressure and surface wind conditions in the larger North Pacific area. The dominating atmospheric pressure patterns obtained from the climate model run allow in combination with ERA-Interim sea-level pressure and surface winds a reconstruction of the OBP variability in the North Pacific from atmospheric model data only, which correlates favorably (r=0.7) with GRACE ocean bottom pressure observations. The regression results indicate that GRACE-based OBP observations are indeed sensitive to changes in the prevailing sea-level pressure and thus surface wind conditions in the North Pacific, thereby opening opportunities to constrain atmospheric models from satellite gravity observations over the oceans

Clinical Interventions to Promote Breastfeeding by Latinas: A Meta-analysis

Breastfeeding duration and exclusivity among Latinas fall below recommended levels, indicating a need for targeted interventions. The effectiveness of clinical breastfeeding interventions for Latinas remains unclear

Measurements of total odd nitrogen (NOy) aboard MOZAIC in-service aircraft: instrument design, operation and performance

A small system for the unattended measurement of total odd nitrogen (NOy, i.e., the sum of NO and its atmospheric oxidation products) aboard civil in-service aircraft in the framework of MOZAIC is described. The instrument employs the detection of NO by its chemiluminescence with O-3 in combination with catalytic conversion of the other NOy compounds to NO at 300degreesC on a gold surface in the presence of H-2. The instrument has a sensitivity of 0.4-0.7 cps/ppt and is designed for unattended operation during 1-2 service cycles of the aircraft (400-800 flight hours). The total weight is 50 kg, including calibration system, compressed gases, mounting, and safety measures. The layout and inlet configuration are governed by requirements due to the certification for passenger aircraft. Laboratory tests are described regarding the conversion efficiency for NO2 and HNO3 (both > 98%). Interference by non-NOy species is <1% for CH3CN and NH3, <5 x 10(-5) % for N2O (corresponding to <0.2 ppt fake NOy from ambient N2O) and 100% for HCN. The time response of the instrument is <1 s (90% change) for NO2. The response for HNO3 is nonlinear: 20 s for 67%, 60 s for 80%, and 150 s for 90% response, respectively

Effectiveness of Internal vs. External SEU Scrubbing Mitigation Strategies in a Xilinx FPGA: Design, Test, and Analysis

We compare two scrubbing mitigation schemes for Xilinx FPGA devices. The design of the scrubbers is briefly discussed along with an examination of mitigation limitations. Proton and Heavy Ion data are then presented and analyzed

Per- and polyfluoroalkyl substances (PFAS) exposure and thyroid cancer risk

BACKGROUND: Although per- and polyfluoroalkyl substances (PFAS) exposure is a potential contributor to the increasing thyroid cancer trend, limited studies have investigated the association between PFAS exposure and thyroid cancer in human populations. We therefore investigated associations between plasma PFAS levels and thyroid cancer diagnosis using a nested case-control study of patients with thyroid cancer with plasma samples collected at/before cancer diagnosis. METHODS: 88 patients with thyroid cancer using diagnosis codes and 88 healthy (non-cancer) controls pair-matched on sex, age (±5 years), race/ethnicity, body mass index, smoking status, and year of sample collection were identified in the BioMe population (a medical record-linked biobank at the Icahn School of Medicine at Mount Sinai in New York); 74 patients had papillary thyroid cancer. Eight plasma PFAS were measured using untargeted analysis with liquid chromatography-high resolution mass spectrometry and suspect screening. Associations between individual PFAS levels and thyroid cancer were evaluated using unconditional logistic regression models to estimate adjusted odds ratios (OR adj) and 95% confidence intervals (CI). FINDINGS: There was a 56% increased rate of thyroid cancer diagnosis per doubling of linear perfluorooctanesulfonic acid (n-PFOS) intensity (OR adj, 1.56, 95% CI: 1.17-2.15, P = 0.004); results were similar when including patients with papillary thyroid cancer only (OR adj, 1.56, 95% CI: 1.13-2.21, P = 0.009). This positive association remained in subset analysis investigating exposure timing including 31 thyroid cancer cases diagnosed ≥1 year after plasma sample collection (OR adj, 2.67, 95% CI: 1.59-4.88, P < 0.001). INTERPRETATION: This study reports associations between exposure to PFAS and increased rate of (papillary) thyroid cancer. Thyroid cancer risk from PFAS exposure is a global concern given the prevalence of PFAS exposure. Individual PFAS studied here are a small proportion of the total number of PFAS supporting additional large-scale prospective studies investigating thyroid cancer risk associated with exposure to PFAS chemicals. FUNDING: National Institutes of Health grants and The Andrea and Charles Bronfman Philanthropies

Mathematical model insights into arsenic detoxification

<p>Abstract</p> <p>Background</p> <p>Arsenic in drinking water, a major health hazard to millions of people in South and East Asia and in other parts of the world, is ingested primarily as trivalent inorganic arsenic (iAs), which then undergoes hepatic methylation to methylarsonic acid (MMAs) and a second methylation to dimethylarsinic acid (DMAs). Although MMAs and DMAs are also known to be toxic, DMAs is more easily excreted in the urine and therefore methylation has generally been considered a detoxification pathway. A collaborative modeling project between epidemiologists, biologists, and mathematicians has the purpose of explaining existing data on methylation in human studies in Bangladesh and also testing, by mathematical modeling, effects of nutritional supplements that could increase As methylation.</p> <p>Methods</p> <p>We develop a whole body mathematical model of arsenic metabolism including arsenic absorption, storage, methylation, and excretion. The parameters for arsenic methylation in the liver were taken from the biochemical literature. The transport parameters between compartments are largely unknown, so we adjust them so that the model accurately predicts the urine excretion rates of time for the iAs, MMAs, and DMAs in single dose experiments on human subjects.</p> <p>Results</p> <p>We test the model by showing that, with no changes in parameters, it predicts accurately the time courses of urinary excretion in mutiple dose experiments conducted on human subjects. Our main purpose is to use the model to study and interpret the data on the effects of folate supplementation on arsenic methylation and excretion in clinical trials in Bangladesh. Folate supplementation of folate-deficient individuals resulted in a 14% decrease in arsenicals in the blood. This is confirmed by the model and the model predicts that arsenicals in the liver will decrease by 19% and arsenicals in other body stores by 26% in these same individuals. In addition, the model predicts that arsenic methyltransferase has been upregulated by a factor of two in this population. Finally, we also show that a modification of the model gives excellent fits to the data on arsenic metabolism in human cultured hepatocytes.</p> <p>Conclusions</p> <p>The analysis of the Bangladesh data using the model suggests that folate supplementation may be more effective at reducing whole body arsenic than previously expected. There is almost no data on the upregulation of arsenic methyltransferase in populations chronically exposed to arsenic. Our model predicts upregulation by a factor of two in the Bangladesh population studied. This prediction should be verified since it could have important public health consequences both for treatment strategies and for setting appropriate limits on arsenic in drinking water. Our model has compartments for the binding of arsenicals to proteins inside of cells and we show that these comparments are necessary to obtain good fits to data. Protein-binding of arsenicals should be explored in future biochemical studies.</p

Advancing the use of noncoding RNA in regulatory toxicology: Report of an ECETOC workshop

The European Centre for the Ecotoxicology and Toxicology of Chemicals (ECETOC) organised a workshop to discuss the state-of-the-art research on noncoding RNAs (ncRNAs) as biomarkers in regulatory toxicology and as analytical and therapeutic agents. There was agreement that ncRNA expression profiling data requires careful evaluation to determine the utility of specific ncRNAs as biomarkers. To advance the use of ncRNA in regulatory toxicology, the following research priorities were identified: (1) Conduct comprehensive literature reviews to identify possibly suitable ncRNAs and areas of toxicology where ncRNA expression profiling could address prevailing scientific deficiencies. (2) Develop consensus on how to conduct ncRNA expression profiling in a toxicological context. (3) Conduct experimental projects, including, e.g., rat (90-day) oral toxicity studies, to evaluate the toxicological relevance of the expression profiles of selected ncRNAs. Thereby, physiological ncRNA expression profiles should be established, including the biological variability of healthy individuals. To substantiate the relevance of key ncRNAs for cell homeostasis or pathogenesis, molecular events should be dose-dependently linked with substance-induced apical effects. Applying a holistic approach, knowledge on ncRNAs, 'omics and epigenetics technologies should be integrated into adverse outcome pathways to improve the understanding of the functional roles of ncRNAs within a regulatory context

Indonesian Throughflow drove Australian climate form humid Pliocene to arid Pleistocene

Late Miocene to mid-Pleistocene sedimentary proxy records reveal that northwest Australia underwent an abrupt transition from dry to humid climate conditions at 5.5 million years (Ma), likely receiving year-round rainfall, but after ~3.3 Ma, climate shifted toward an increasingly seasonal precipitation regime. The progressive constriction of the Indonesian Throughflow likely decreased continental humidity and transferred control of northwest Australian climate from the Pacific to the Indian Ocean, leading to drier conditions punctuated by monsoonal precipitation. The northwest dust pathway and fully established seasonal and orbitally controlled precipitation were in place by ~2.4 Ma, well after the intensification of Northern Hemisphere glaciation. The transition from humid to arid conditions was driven by changes in Pacific and Indian Ocean circulation and regional atmospheric moisture transport, influenced by the emerging Maritime Continent. We conclude that the Maritime Continent is the switchboard modulating teleconnections between tropical and high-latitude climate systems.published_or_final_versio