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The remote and high elevation regions of central Asia are influenced by black carbon (BC) emissions from a variety of locations. BC deposition contributes to melting of glaciers and questions exist, of both scientific and policy interest, as to the origin of the BC reaching the glaciers. We use the adjoint of the GEOS-Chem model to identify the location from which BC arriving at a variety of locations in the Himalayas and Tibetan Plateau originates. We then calculate its direct and snow-albedo radiative forcing. We analyze the seasonal variation in the origin of BC using an adjoint sensitivity analysis, which provides a detailed map of the location of emissions that directly contribute to black carbon concentrations at receptor locations. We find that emissions from northern India and central China contribute the majority of BC to the Himalayas, although the precise location varies with season. The Tibetan Plateau receives most BC from western and central China, as well as from India, Nepal, the Middle East, Pakistan and other countries. The magnitude of contribution from each region varies with season and receptor location. We find that sources as varied as African biomass burning and Middle Eastern fossil fuel combustion can significantly contribute to the BC reaching the Himalayas and Tibetan Plateau. We compute radiative forcing in the snow-covered regions and find the forcing due to the BC induced snow-albedo effect to vary from 5–15 W m−2 within the region, an order of magnitude larger than radiative forcing due to the direct effect, and with significant seasonal variation in the northern Tibetan Plateau. Radiative forcing from reduced snow albedo likely accelerates glacier melting. Our analysis may help inform mitigation efforts to slow the rate of glacial melt by identifying regions that make the largest contributions to BC deposition in the Himalayas and Tibetan Plateau.

Although obesity in pregnancy continues to be associated with ongoing health problems, many clinicians have been reluctant to place nondiabetic, obese, pregnant women on a monitored, calorie-appropriate nutritional regimen for fear of fetal growth restriction, low birth weight, or starvation ketosis. A total of 257 patients were enrolled in the randomized study, with a loss-to-follow-up rate of 9.73%. Patients were assigned randomly to either the control (unmonitored) group (n = 116), consisting of conventional prenatal dietary management, or to the study (monitored) group (n = 116), which was prescribed a balanced nutritional regimen and were asked to record in a diary all of the foods eaten during each day. Women were eligible for the study if they were pregnant with a single fetus between 12 and 28 weeks of gestation and had a prepregnancy body mass index of more than 30 kg/m2. The primary outcome was to compare perinatal outcomes in the control vs the study groups. The secondary measure was to compare outcomes in adherent and nonadherent patients in the study group. Omnibus MANOVA showed statistically significant differences between the study and control groups regarding 3 variables: (1) gestational hypertension, p < .46; (2) mother’s last weight before delivery, p < .001; and (3) mother’s 6-week postpartum weight, p .001. Patients gaining 15 pounds or more during their pregnancy showed statistically significant differences between the groups for 8 variables. Obese pregnant women may be placed on a healthy, well-balanced, monitored nutritional program during their antepartum course without adverse perinatal outcomes. (Clinicaltrials.gov identifier: NCT00740766)

High-speed biplane x-ray and neutral density targets were used to examine brain displacement and deformation during impact. Relative motion, maximum principal strain, maximum shear strain, and intracranial pressure were measured in thirty-five impacts using eight human cadaver head and neck specimens. The effect of a helmet was evaluated. During impact, local brain tissue tends to keep its position and shape with respect to the inertial frame, resulting in relative motion between the brain and skull and deformation of the brain. The local brain motions tend to follow looping patterns. Similar patterns are observed for impact in different planes, with some degree of posterior-anterior and right-left symmetry. Peak coup pressure and pressure rate increase with increasing linear acceleration, but coup pressure pulse duration decreases. Peak average maximum principal strain and maximum shear are on the order of 0.09 for CFC 60 Hz data for these tests. Peak average maximum principal strain and maximum shear decrease with increasing linear acceleration, coup pressure, and coup pressure rate. Linear and angular acceleration of the head are reduced with use of a helmet, but strain increases. These results can be used for the validation of finite element models of the human head.

We validate satellite methane observations from the Tropospheric Emission Spectrometer (TES) with 151 aircraft vertical profiles over the Pacific from the HIAPER Pole-to-Pole Observation (HIPPO) program. We find that a collocation window of ±750 km and ±24 h does not introduce significant error in comparing TES and aircraft profiles. We validate both the TES standard product (V004) and an experimental product with two pieces of information in the vertical (V005). We determine a V004 mean bias of 65.8 ppb and random instrument error of 43.3 ppb. For V005 we determine a mean bias of 42.3 ppb and random instrument error of 26.5 ppb in the upper troposphere, and mean biases (random instrument errors) in the lower troposphere of 28.8 (28.7) and 16.9 (28.9) ppb at high and low latitudes respectively. Even when V005 cannot retrieve two pieces of information it still performs better than V004. An observation system simulation experiment (OSSE) with the GEOS-Chem chemical transport model (CTM) and its adjoint shows that TES V004 has only limited value for constraining methane sources. Our successful validation of V005 encourages its production as a standard retrieval to replace V004.

We assess the impact of transport of pollution from midlatitudes on the abundance of ozone in the Arctic in summer 2006 using the GEOS‐Chem global chemical transport model and its adjoint. We find that although the impact of midlatitude emissions on ozone abundances in the Arctic is at a maximum in fall and winter, in July transport from North America, Asia, and Europe together contributed about 25% of surface ozone abundances in the Arctic. Throughout the summer, the dominant source of ozone in the Arctic troposphere was photochemical production within the Arctic, which accounted for more than 50% of the ozone in the Arctic boundary layer and as much as 30%–40% of the ozone in the middle troposphere. An adjoint sensitivity analysis of the impact of NOx emissions on ozone at Alert shows that on synoptic time scales in both the lower and middle troposphere, ozone abundances are more sensitive to emissions between 50°N and 70°N, with important influences from anthropogenic, biomass burning, soil, and lightning sources. Although local surface NOx emissions contribute to ozone formation, transport of NOx in the form of peroxyacetyl nitrate (PAN) from outside the Arctic and from the upper troposphere also contributed to ozone production in the lower troposphere. We find that in late May and June the release of NOx from PAN decomposition accounted for 93% and 55% of ozone production at the Arctic surface, respectively. Key Points Midlatitude source regions contribute 10‐25% of Arctic ozone in summer On short time scales, Arctic O3 is most sensitive to NOx emissions at 50‐70N NOx transported as PAN constitutes most of O3 produced in the Arctic spring

Although most nanofabrication techniques can control nano/micro particle (NMP) size over a wide range, the majority of NMPs for biomedical applications exhibits a diameter of ~100 nm. Here, the vascular distribution of spherical particles, from 10 to 1,000 nm in diameter, is studied using intravital microscopy and computational modeling. Small NMPs (≤100 nm) are observed to move with Red Blood Cells (RBCs), presenting an uniform radial distribution and limited near-wall accumulation. Larger NMPs tend to preferentially accumulate next to the vessel walls, in a size-dependent manner (~70% for 1,000 nm NMPs). RBC-NMP geometrical interference only is responsible for this behavior. In a capillary flow, the effective radial dispersion coefficient of 1,000 nm particles is ~3-fold larger than Brownian diffusion. This suggests that sub-micron particles could deposit within diseased vascular districts more efficiently than conventional nanoparticles.

We estimate black carbon (BC) emissions in the western United States for July–September 2006 by inverting surface BC concentrations from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network using a global chemical transport model (GEOS-Chem) and its adjoint. Our best estimate of the BC emissions is 49.9 Gg at 2° × 2.5° (a factor of 2.1 increase) and 47.3 Gg at 0.5° × 0.667° (1.9 times increase). Model results now capture the observed major fire episodes with substantial bias reductions (~ 35 % at 2° × 2.5° and ~ 15 % at 0.5° × 0.667°). The emissions are ~ 20–50 % larger than those from our earlier analytical inversions (Mao et al., 2014). The discrepancy is especially drastic in the partitioning of anthropogenic versus biomass burning emissions. The August biomass burning BC emissions are 4.6–6.5 Gg and anthropogenic BC emissions 8.6–12.8 Gg, varying with the model resolution, error specifications, and subsets of observations used. On average both anthropogenic and biomass burning emissions in the adjoint inversions increase 2-fold relative to the respective a priori emissions, in distinct contrast to the halving of the anthropogenic and tripling of the biomass burning emissions in the analytical inversions. We attribute these discrepancies to the inability of the adjoint inversion system, with limited spatiotemporal coverage of the IMPROVE observations, to effectively distinguish collocated anthropogenic and biomass burning emissions on model grid scales. This calls for concurrent measurements of other tracers of biomass burning and fossil fuel combustion (e.g., carbon monoxide and carbon isotopes). We find that the adjoint inversion system as is has sufficient information content to constrain the total emissions of BC on the model grid scales.

Wind power is currently one of the most promising energy sources, both in Europe and across-the world. In Poland, a large annual increase in the installed wind turbine capacity has been observed for many years. Power generation from wind turbines is related to wind parameters, which, in turn, result from changes in atmospheric conditions. This is why the observed wind speed has different values depending on time and place (location and altitude). This affects the amount of generated power and the continuity of its production. The authors of this article carried out an analysis of the potential of the diversification of wind energy sources in Poland. The research was conducted with the aim of assessing the variability of the potential production of electrical energy. The analysis concerned the volatility of the wind speed and the variability of available turbine power, as well as its distribution over appropriate points in the location grid - a set of combinations for every point in the location grid, aiming to present the effect of the diversification. For this purpose, the standard deviation in relation to the average power of wind turbines was selected as a comparative measure. The analyses were conducted based on historical wind measurements and data retrieved from the MERRA database. The results indicate that it is more advantageous for both the Polish power system and power plant owners (energy companies) to build smaller wind farms that are distant from each other and to group them in pairs in order to create a virtual power plant. Despite a wind-farm downtime of less than 15% for most of Poland in the analysed period, the existing power differences do not provide the possibility of ensuring continuity of energy supplies.

The synthesis conditions of quercetin-8-sulfonic acid and sodium salt of sulfonated quercetin were determined. The molecular formulae of obtained compounds are: C 15 H 10 O 10 S·4H 2 O and C 15 H 9 O 10 SNa·4H 2 O. On the basis of spectral methods UV–Vis, IR, and 1 H NMR it was stated that the sulfonation of quercetin occurs at 8-C position of the A ring. The complexing properties of NaQSA–8 were confirmed by synthesis of a solid complex with Fe(II) ions. The NaQSA-8 formed a complex with Fe(II) ions at pH 5 with the metal excess ( c M : c L  = 7:1). The chelation site was analyzed using spectroscopy methods. It was found that chelation of the metal ions occurs at the 4C=O, 3-OH and 3′-OH, and 4′-OH sites of the molecule NaQSA-8. Thermal decomposition of the compounds was carried out in air and nitrogen gas carries. The TG-FTIR-MS technique was employed to study decomposition pathway. The dehydration process was discussed in relation to of the nature of water contained in the compounds.

Xanthomonas citri subsp. citri (Xac) is the causative agent of citrus canker, a plant disease that significantly impacts citriculture. In earlier work, we showed that alkylated derivatives of gallic acid have antibacterial action against Xac and target both the cell division protein FtsZ and membrane integrity in Bacillus subtilis. Here, we have purified native XacFtsZ and characterized its GTP hydrolysis and polymerization properties. In a surprising manner, inhibition of XacFtsZ activity by alkyl gallates is not as strong as observed earlier with B. subtilis FtsZ. As the alkyl gallates efficiently permeabilize Xac membranes, we propose that this is the primary mode of antibacterial action of these compounds. We have purified native Xac FtsZ and characterized its GTP hydrolysis and polymerization properties. Inhibition of XacFtsZ activity by alkyl gallates is not as strong as observed earlier with Bacillus subtilis FtsZ. We propose that membrane permeabilization is the primary mode of antibacterial action of alkyl gallates.