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PROVAT – a versatile tool for Voronoi tessellation analysis of protein structures and complexes
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A self-powered pumping system for in situ extraction of particulate and dissolved materials from large volumes of seawater
A pumping system has been developed for the in situ extraction of particles and of dissolved constituents from large volumes of seawater. The assembly consists of a battery-powered submersible pump, filters, and chemisorptive
cartridges; it is entirely self-contained and has been used successfully
on ship's hydrographic wire to depths as great as 5800 m. The pump is
designed to operate at a maximum pressure drop of 66 cm of Hg; flow rates
have varied from 1.3 to 5.1 liters/min. We have sampled volumes as large as
758 liters, and the measured battery drain suggests that volumes several
times this could be pumped at any depth. The system is being used to study
a variety of artificial radionuclides, but modifications of the filter or
chemisorbent units would make it useful in many other geochemical
applications.Prepared for the U.S. Department of Energy under Contracts
DE-AC02-76EV03563 and DE-AC02-81EV10694 and through Sandia Laboratories under Contracts 13-2562 and 16/3112
Robust Weak-lensing Mass Calibration of Planck Galaxy Clusters
In light of the tension in cosmological constraints reported by the Planck
team between their SZ-selected cluster counts and Cosmic Microwave Background
(CMB) temperature anisotropies, we compare the Planck cluster mass estimates
with robust, weak-lensing mass measurements from the Weighing the Giants (WtG)
project. For the 22 clusters in common between the Planck cosmology sample and
WtG, we find an overall mass ratio of \left =
0.688 \pm 0.072. Extending the sample to clusters not used in the Planck
cosmology analysis yields a consistent value of from 38 clusters in common. Identifying the
weak-lensing masses as proxies for the true cluster mass (on average), these
ratios are lower than the default mass bias of 0.8 assumed in
the Planck cluster analysis. Adopting the WtG weak-lensing-based mass
calibration would substantially reduce the tension found between the Planck
cluster count cosmology results and those from CMB temperature anisotropies,
thereby dispensing of the need for "new physics" such as uncomfortably large
neutrino masses (in the context of the measured Planck temperature anisotropies
and other data). We also find modest evidence (at 95 per cent confidence) for a
mass dependence of the calibration ratio and discuss its potential origin in
light of systematic uncertainties in the temperature calibration of the X-ray
measurements used to calibrate the Planck cluster masses. Our results exemplify
the critical role that robust absolute mass calibration plays in cluster
cosmology, and the invaluable role of accurate weak-lensing mass measurements
in this regard.Comment: 5 pages, 2 figure
Biliary Duct Granular Cell Tumor: A Rare But Surgically Curable Benign Tumor
Granulosa cell tumors are rare benign tumors which may be found throughout the body. Rare cases are
isolated within the biliary tree. If completely resected, surgical excision is curative
Effects of cardiovascular lifestyle change on lipoprotein subclass profiles defined by nuclear magnetic resonance spectroscopy
<p>Abstract</p> <p>Background</p> <p>Low-density lipoprotein (LDL) cholesterol lowering is a primary goal in clinical management of patients with cardiovascular disease, but traditional cholesterol levels may not accurately reflect the true atherogenicity of plasma lipid profiles. The size and concentration of lipoprotein particles, which transport cholesterol and triglycerides, may provide additional information for accurately assessing cardiovascular risk. This study evaluated changes in plasma lipoprotein profiles determined by nuclear magnetic resonance (NMR) spectroscopy in patients participating in a prospective, nonrandomized lifestyle modification program designed to reverse or stabilize progression of coronary artery disease (CAD) to improve our understanding of lipoprotein management in cardiac patients.</p> <p>Results</p> <p>The lifestyle intervention was effective in producing significant changes in lipoprotein subclasses that contribute to CAD risk. There was a clear beneficial effect on the total number of LDL particles (-8.3%, p < 0.05 compared to matched controls), small dense LDL particles (-9.5%, p < 0.05), and LDL particle size (+0.8%; p < 0.05). Likewise, participants showed significant improvement in traditional CAD risk factors such as body mass index (-9.9%, p < 0.01 compared to controls), total cholesterol (-5.5%, p < 0.05), physical fitness (+37.2%, p < 0.01), and future risk for CAD (-7.9%, p < 0.01). Men and women responded differently to the program for all clinically-relevant variables, with men deriving greater benefit in terms of lipoprotein atherogenicity. Plasma lipid and lipoprotein responses to the lifestyle change program were not confounded by lipid-lowering medications.</p> <p>Conclusion</p> <p>In <it>at risk </it>patients motivated to participate, an intensive lifestyle change program can effectively alter traditional CAD risk factors and plasma lipoprotein subclasses and may reduce risk for cardiovascular events. Improvements in lipoprotein subclasses are more evident in men compared to women.</p
Mobilisation of arsenic from bauxite residue (red mud) affected soils: effect of pH and redox conditions
The tailings dam breach at the Ajka alumina plant, western Hungary in 2010 introduced ~1 million m3 of red mud suspension into the surrounding area. Red mud (fine fraction bauxite residue) has a characteristically alkaline pH and contains several potentially toxic elements, including arsenic. Aerobic and anaerobic batch experiments were prepared using soils from near Ajka in order to investigate the effects of red mud addition on soil biogeochemistry and arsenic mobility in soil–water experiments representative of land affected by the red mud spill. XAS analysis showed that As was present in the red mud as As(V) in the form of arsenate. The remobilisation of red mud associated arsenate was highly pH dependent and the addition of phosphate to red mud suspensions greatly enhanced As release to solution. In aerobic batch experiments, where red mud was mixed with soils, As release to solution was highly dependent on pH. Carbonation of these alkaline solutions by dissolution of atmospheric CO2 reduced pH, which resulted in a decrease of aqueous As concentrations over time. However, this did not result in complete removal of aqueous As in any of the experiments. Carbonation did not occur in anaerobic experiments and pH remained high. Aqueous As concentrations initially increased in all the anaerobic red mud amended experiments, and then remained relatively constant as the systems became more reducing, both XANES and HPLC–ICP-MS showed that no As reduction processes occurred and that only As(V) species were present. These experiments show that there is the potential for increased As mobility in soil–water systems affected by red mud addition under both aerobic and anaerobic conditions
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