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Lake-effect snowfall (LES) occurs when cold air moves across open lakes. LES is expected to occur more frequently over the TP, due to the intensified lake expansion caused by intensified global warming. Thus, there is an urgent need to comprehensively assess the LES over the TP. Here, we revealed that the LES is triggered by westerly southward shift leading to the drop in air temperature and is positively correlated with lake area, wind speed and longitude across 12 large lakes (>300 km2) based on satellite observations and reanalysis data. Using a sensitivity model simulation, we determined that large lakes in the southern TP contributed to more than 50% of the snowfall in the downwind area in 2013. Projections indicate that the westerly-triggered LES will increase under the future RCP4.5 climate warming scenario, highlighting the importance of developing adaptive policies to address the growing risks associated with future LES. [ABSTRACT FROM AUTHOR]

Background and Purpose: Defective insulin signalling and dysfunction of the endoplasmic reticulum (ER), driven by excessive lipid accumulation in the liver, is a characteristic feature in the pathogenesis of non‐alcoholic fatty liver disease (NAFLD). Thromboxane A2 (TXA2), an arachidonic acid metabolite, is significantly elevated in obesity and plays a crucial role in hepatic gluconeogenesis and adipose tissue macrophage polarization. However, the role of liver TXA2/TP receptors in insulin resistance and lipid metabolism is largely unknown. Experimental Approach: TP receptor knockout (TP−/−) mice were generated and fed a high‐fat diet for 16 weeks. Insulin sensitivity, ER stress responses and hepatic lipid accumulation were assessed. Furthermore, we used primary hepatocytes to dissect the mechanisms by which the TXA2/TP receptor axis regulates insulin signalling and hepatocyte lipogenesis. Key Results: TXA2 was increased in diet‐induced obese mice, and depletion of TP receptors in adult mice improved systemic insulin resistance and hepatic steatosis. Mechanistically, we found that the TXA2/TP receptor axis disrupts insulin signalling by activating the Ca2+/calcium calmodulin‐dependent kinase II γ (CaMKIIγ)–protein kinase RNA‐like endoplasmic reticulum kinase (PERK)–C/EBP homologous protein (Chop)–tribbles‐like protein 3 (TRB3) axis in hepatocytes. In addition, our results revealed that the TXA2/TP receptor axis directly promoted lipogenesis in primary hepatocytes and contributed to Kupffer cell inflammation. Conclusions and Implications: The TXA2/TP receptor axis facilitates insulin resistance through Ca2+/CaMKIIγ to activate PERK–Chop–TRB3 signalling. Inhibition of hepatocyte TP receptors improved hepatic steatosis and inflammation. The TP receptor is a new therapeutic target for NAFLD and metabolic syndrome. [ABSTRACT FROM AUTHOR]

[Display omitted] Aberrant arachidonic acid metabolism has been implicated in multiple pathophysiological conditions, and the downstream prostanoids levels are associated with adipocyte dysfunction in obesity. However, the role of thromboxane A 2 (TXA 2) in obesity remains unclear. We observed that TXA 2 , through its receptor TP, is a candidate mediator in obesity and metabolic disorders. Obese mice with upregulated TXA 2 biosynthesis (TBXAS1) and TXA 2 receptor (TP) expression in caused insulin resistance and macrophage M1 polarization in white adipose tissue (WAT), which can be prevented by treatment with aspirin. Mechanistically, the activation of TXA 2 -TP signaling axis leads to accumulation of protein kinase Cɛ (PKCɛ), thereby enhancing free fat acid (FFA) induced Toll-like receptor4 (TLR4) proinflammatory macrophage activation and the tumor necrosis factor–a (TNF-a) production in adipose tissues. Importantly, TP knockout mice reduced the accumulation of proinflammatory macrophages and adipocyte hypertrophy in WAT. Thus, our findings demonstrate that TXA 2 -TP axis plays a crucial role in obesity-induced adipose macrophage dysfunction, and rational targeting TXA 2 pathway may improve obesity and its associated metabolic disorders in future. In this work, we establish previously unknown role of TXA 2 -TP axis in WAT. These findings might provide new insight into the molecular pathogenesis of insulin resistance, and indicate rational targeting TXA 2 pathway to improve obesity and its associated metabolic disorders in future. [ABSTRACT FROM AUTHOR]

Nam Co (Heavenly Lake) not only responds sensitively to climate change, but also exerts significant influences on climate change. Previous studies revealed that the lake effects from the North American Great Lakes shown interaction with climate changes. However, the lakes effect of more than 1200 lakes with an area of 47,000 km 2 on the Tibetan Plateau remains less studied. In this study, we analyzed the spatial distribution of precipitation in the Nam Co Basin during July–August and November–December to clarify the lake effect. We found that the lake cooling effect during July–August and lake heating effect during November–December resulted in the spatial differences of precipitation within the Nam Co Basin. These effects generally caused more precipitation in the south than in the north during July–August, and more precipitation in the east than in the west during November–December. Weakening Indian monsoon and climate warming led to an increased north–south precipitation difference in the Nam Co Basin. However, the precipitation differences between the west and east during November–December decreased with climate warming. The intensification of the westerly might be responsible for the particular phenomenon. [ABSTRACT FROM AUTHOR]

Pulsed power supply connects energy-dissipation devices by coaxial cable. The temperature of coaxial cable used for repetitious discharge of pulsed power supply can rise highly. This paper focuses on the transient temperature characteristic of coaxial cable under the condition of repetitious pulse high current. In consideration of time and resource consuming of the general 3-D simulation software, 1-D thermal network differential equations (TNDEs) are introduced. In addition, the Arnoldi process is applied to reduce TNDEs’ complexity due to dense space discretization. For model validation and verification, a statistical design of experiments over the parameters of discharge period and current level is organized. The trends of transient temperature around the coaxial cable surface and outer conductor during discharging and cooling process are measured. The experimental results have a good agreement with calculation results. The comparison results show that the theoretical analysis is suitable for analyzing the coaxial cable temperature with different running conditions. [ABSTRACT FROM PUBLISHER]

Aiming at the interferences caused by vibrations on the target monitoring system of satellite platforms, an experimental system of optical–mechanical–electrical joint image stabilization based on inertial sensors and piezoelectric fast mirrors was studied. First of all, the data from the fiber optic gyroscope and the detector are combined and processed. After that, the predicted intentional velocity is subtracted from the real-time gyroscope data, and the vibration displacement is obtained using an integral. The feedback amount is calculated using the processor according to the vibration displacement, the piezoelectric fast mirror is controlled to compensate the vibration interferences, and the purpose of stabilizing the images is achieved. The experimental results show that under a vibration interference of 300 μ rad /s, the image stabilization control frequency of the system reaches 500 Hz, the relative error between image frames is better than 3 μ rad , and the intra-frame stabilization performance of the detector meets the requirements on stabilized image and target detection for space targets on the star-carrying platform. [ABSTRACT FROM AUTHOR]

The lactate receptor G protein-coupled receptor 81 (GPR81) has been recently implicated in lipolysis in adipose tissue. In this study, we accidently discovered the role of GPR81 in hepatic lipid metabolism. Data clearly showed that hepatic GPR81 was markedly up-regulated in fasted mice, whereas it was severely down-regulated in obese mice. Genetic deficiency of GPR81 impaired ketogenic response, enhanced hepatic lipid accumulation, and exacerbated hepatosteatosis under acute fasting conditions. Mechanically, we demonstrated that hepatic GPR81 might function as a modulator of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), activate the downsream transcription of liver carnitine o-palmitoyltransferase 1(L-CPT1), and thereby control the influx of fatty acids into mitochondria for β-oxidation. Importantly, metformin improved experimental nonalcoholic fatty liver disease (NAFLDs) in a GPR81-dependent manner. Collectively, GPR81 was critical for hepatic lipid homeostasis and activation of hepatic GPR81 might represent a promising strategy for the treatment of obesity and its associated metabolic disorders. The pathway that GPR81 mediates hepatic lipid metabolism and the therapeutic effect of metformin. Fasting up-regulates the expression of hepatic GPR81, which might function as a modulator of PGC-1a, activate the downsream transcription of L-CPT1, and thereby control the influx of fatty acids into mitochondria for β-oxidation during fasting. Similar to fasting, metformin serves as a CRMs to regulate hepatic lipid metabolism through p-LKB1 in a GPR81-dependent manner. [Display omitted] [ABSTRACT FROM AUTHOR]

• Snow mass of TP predominantly increased until 1981 and decreased after 1981. • North of 35° N, changes in precipitation controlled snow mass trends. • South of 35° N, intensified warming resulted in the snow mass reversal. The snowpack on the Tibetan Plateau (TP), which feeds ten major rivers and supplies freshwater to heavily populated downstream areas, is undergoing major changes owing to climate change. However, the impact of climate change on snowpacks is debated because of the lack of quantitative knowledge about snow mass on the TP. In this study, we collected long time-series data of the snowpack (1961–2018) from 143 stations on the TP at elevations of 1100–4800 m asl and calculated the snow water equivalent based on the observed snow depths and simulated snow densities to examine the snow mass trends, transition patterns of the trends, and their climatic causes. The results show that snow mass on the TP experienced a large increase (1.56 mm/y) until 1981 and a decrease (−0.58 mm/y) after 1981. The snow mass trends exhibited three transition patterns before and after 1981: increasing snow mass trends intensified and decreasing trends weakened on the north edge of the TP; snow loss intensified in the northeast region; and snow mass trends reversed from increasing to decreasing in the south. North of 35° N, the snow mass variability was controlled by precipitation changes. South of 35° N, warming affected only a few stations below 3000 m before 1981, and the reinforced warming then resulted in increased snow mass loss at almost all the stations after 1981. Warming-driven snow mass reversals and the continued warming on the TP could lead to significant water management challenges in densely populated downstream areas. [ABSTRACT FROM AUTHOR]

Although the pulsed power supply (PPS) based on capacitor has been successfully applied to engineering prototype of electromagnetic (EM) railgun, its large volume makes it poor adaptability and flexibility due to relatively low energy storage density. In this article, a novel hybrid energy storage system based on battery and pulsed alternator is proposed. The topology principle of the system, the design scheme of the pulsed alternator, and the cosimulation results of multimodules are described in detail. The research results show that the proposed system can be used as the driving power of EM railgun with 40 MJ muzzle kinetic energy, and the effective energy storage density (energy released in a single pulse) of the pulsed alternator can reach 6.3 MJ/m3. Taking into account the charging motors, converter thyristors, and other auxiliary components, the effective energy storage density of PPS system will be 3 MJ/m3 and the overall volume can be reduced to one-third of the current capacitive PPS. [ABSTRACT FROM AUTHOR]

Background: Interleukin-33 (IL-33) plays a pivotal role in regulating innate immune response and metabolic homeostasis. However, whether its circulating level is correlated with obesity and metabolic disorders in humans remains largely unknown. We aimed to address this gap by determining IL-33 serum level and its downstream type 2 inflammatory cytokines interleukin-5 (IL-5) and interleukin-13 (IL-13) in overweight/obese population, and analyzing the specific associations between IL-33 and obesity metabolic phenotypes.Methods: 217 subjects were enrolled and divided into three groups: healthy control (HC) subjects, metabolically healthy overweight/obese (MHOO) subjects and metabolically unhealthy overweight/obese (MUOO) subjects. Circulating levels of IL-33, IL-5 and IL-13 were measured using ELISA analyses. Multivariate regression analyses were further performed to determine the independent association between IL-33 and obesity metabolic phenotypes.Results: Circulating levels of IL-33 were significantly elevated in subjects of MUOO group compared with HC group and MHOO group, while no significant difference was observed between the latter two groups in IL-33 levels. Consistent with this, serum levels of IL-5/13 were higher in the MUOO group compared with HC and MHOO groups. After adjusted for all confounders, MUOO phenotype was significantly associated with increased IL-33 serum levels (OR = 1.70; 95% CI 1.09-2.64; p = 0.019). With the MHOO group as the reference population, higher circulating level of IL-33 was also positively associated with MUOO phenotype after adjusting for confounders (OR = 1.50; 95% CI 1.20-1.88; p = 2.91E-4). However, there was no significant association between MHOO phenotype and IL-33 levels (p = 0.942). Trend analysis further confirmed the positive correlation between MUOO phenotype and IL-33 level (p for trend = 0.019). Additionally, IL-33 was significantly and positively correlated with diastolic blood pressure (DBP), total cholesterol (TC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), white blood cell (WBC), neutrophil and IL-5 only in MUOO group, while inversely correlated with high density lipoprotein cholesterol (HDL-C) in MHOO subjects.Conclusion: Circulating levels of IL-33 were significantly elevated in overweight/obese Chinese adults with metabolic disorders. Increased levels of IL-33 were positively associated with metabolically unhealthy overweight/obese phenotype and several metabolic syndrome risk factors. [ABSTRACT FROM AUTHOR]

In this study, we explore whether the pro-osteogenic effects of sialoglycoprotein from Carassius auratus eggs (Ca-SGP) involve mesenchymal stem cells (MSCs). Ovariectomized osteoporotic mice treated with Ca-SGP had increased bone formation and reduced bone marrow adipose tissue. As MSCs are common progenitors of osteoblasts and adipocytes, we isolated MSCs from Ca-SGP-treated mice and found that they tended to differentiate into osteoblasts over adipocytes confirmed by Alizarin red and Oil red O staining. This change was seen at the gene and protein level. To further explore the effect of Ca-SGP on MSCs, we isolated MSCs from healthy mice and treated them with Ca-SGP in vitro. We discovered that Ca-SGP promoted MSC differentiation to osteoblasts. In addition, Ca-SGP promoted osteogenesis and reduced the fat in marrow cavity of adolescent mice. For the first time, our results demonstrate that Ca-SGP promotes osteogenesis via stimulating MSCs to commit to osteoblasts. [ABSTRACT FROM AUTHOR]

Since the late 1990s, lakes in the southern Tibetan Plateau (TP) have shrunk considerably, which contrasts with the rapid expansion of lakes in the interior TP. Although these spatial trends have been well documented, the underlying hydroclimatic mechanisms are not well understood. Since 2013, we have carried out comprehensive water budget observations at Paiku Co, an alpine lake in the central Himalayas. In this study, we investigate water storage and lake level changes on seasonal to decadal time scales based on extensive in-situ measurements and satellite observations. Bathymetric surveys show that Paiku Co has a mean and maximum water depth of 41.1 m and 72.8 m, respectively, and its water storage was estimated to be 109.3 × 10 8 m 3 in June 2016. On seasonal scale between 2013 and 2017, Paiku Co’s lake level decreased slowly between January and May, increased considerably between June and September, and then decreased rapidly between October and January. On decadal time scale, Paiku Co’s lake level decreased by 3.7 ± 0.3 m and water storage reduced by (10.2 ± 0.8) × 10 8 m 3 between 1972 and 2015, accounting for 8.5% of the total water storage in 1972. This change is consistent with a trend towards drier conditions in the Himalaya region during the recent decades. In contrast, glacial lakes within Paiku Co’s basin expanded rapidly, indicating that, unlike Paiku Co, glacial meltwater was sufficient to compensate the effect of the reduced precipitation. [ABSTRACT FROM AUTHOR]

Projected capacitance touch panels are the dominant display/input technology today in smartphones and tablets. The rapid development of these technologies has introduced new and unexpected failure mechanisms, which has driven the development of new sample preparation methods and new applications of analytical techniques for failure analysis. This paper presents some of these mechanisms and methods in two case studies. [ABSTRACT FROM AUTHOR]

The recent evolution of the Karakoram glaciers, widely acknowledged as peculiar, remains poorly understood. The Xiongcaigangri region is in the south of Karakoram, and its glacial melt water has a significant impact on the local water supply and ecosystem. In this work, glacial changes in the Xiongcaigangri region were detected based on topographic maps and Landsat MSS/TM/ETM+/OLI, SRTM4.1 DEM and Glas/ICESat remote sensing data and GIS techniques. The results show that from 1968 to 2013, the total glacier area decreased from 181.10 km 2 to 178.47 km 2 , an overall loss of 2.63 km 2 , or 1.45% of the entire 1968 glacial area. The inverse relationship between the retreating area and the change rate indicates that small glaciers may be retreating faster. The main glacial melting occurred below 6500 m a.s.l, and the reduction of 2.62 km 2 accounts for 99.62% of the total glacial retreat in the area studied. The very slight reduction of 0.01 km 2 over 6500 m a.s.l accounts for only for 0.38% of the total glacial retreat in the area studied. The results also show that the glacier areas are decreasing on all slopes, and larger area losses have been observed on smaller slopes, whereas smaller area losses have been observed on the larger slopes. The different aspects of the study all showed glacier retreat taking place between the period from 1968 to 2013. The largest area decrease is in west, and the area lost in the other aspect was comparatively small. Total glacier mass loss in the Xiongcaigangri region is estimated to be (10.97 ± 22.39) 10 8 m 3 w.e. between 1968 and 2000. The average elevation loss estimated from the ICESat and 2000 SRTM difference was from −4.69–3.40 m per year, and the average elevation loss between SRTM and 1968DEM was from −0.92 to 0.66 m per year. Increasing temperatures along with decreasing precipitation was determined to be the primary factor driving the glacier retreat in the Xiongcaigangri region. [ABSTRACT FROM AUTHOR]

Background Coronary artery disease is highly prevalent in patients with stroke, but because revascularization does not improve major clinical outcomes in patients with stable coronary artery disease relative to intensive medical therapy, routine evaluation for this disease is not warranted in stroke patients. However, it might be warranted in patients destined to undergo vigorous physical therapy. The Locomotor Experience Applied Post-Stroke study, a randomized controlled trial of 408 participants that tested the relative efficacy of two rehabilitation techniques on functional walking level, provided the opportunity to address this question. Aim The study aims to test the efficacy of screening for cardiovascular disease and an exercise tolerance test in assuring safety among patients undergoing vigorous rehabilitation for gait impairment. Methods All participants were screened for serious cardiovascular and pulmonary conditions. At six-weeks poststroke, they also completed a cardiovascular screening inventory and underwent an exercise tolerance test involving bicycle ergometry. Participants received 36, 90-min sessions of a prescribed physical therapy (three per week), initiated at either two-months or six-months poststroke. Results Twenty-nine participants were excluded on the basis of the cardiac screening questionnaire, and 15 failed the exercise tolerance test for cardiovascular reasons. No participant experienced a cardiac event during a treatment session. Two participants experienced myocardial infarctions, but continued in the trial. In three additional participants, myocardial infarctions caused or contributed to death. Conclusions The combination of a negative cardiac screen and the absence of exercise tolerance test failure appeared to have a high negative predictive value for cardiac events during treatment, despite the likelihood of a high prevalence of coronary artery disease in our population. [ABSTRACT FROM AUTHOR]

Abstract: Several early-stage field failures in systems mounting GaAs MMICs were specifically related to MIM capacitor failures. Failure analysis, in turn, classified the failed cases into three main categories, all referred to some weakness in the technological process. The relevant point is that such weak devices can reach the field at such a large scale, despite the very well known nature of their weakness. Ineffective screening at the Manufacturer’s plant is indicted for the problem. Lifetime prediction is attempted, on the user side, based on the detectability of the weak population. [Copyright &y& Elsevier]