ALBERT

Description: ABSTRACT Rainfall is a primary component of the water cycle, and its variability is associated with drought and flood events. This study investigates the trends in annual and seasonal rainfall at 14 rainfall stations in Shaanxi Province, China, using an innovative trend analysis (ITA), Mann–Kendall test and linear regression analysis. Moreover, using ITA, annual rainfall is analysed for different rainfall intensities, and seasonal rainfall is analysed for extreme values. The results show non-uniform trends in rainfall intensities on a regional and seasonal scale. Annual rainfall shows a significant decreasing trend in the Wei River Basin and north of the Loess Plateau. Overall, the trend is reinforced with the increase of rainfall intensity. A few stations show significant trends in seasonal rainfall. Spring rainfall is the major contributor to the decline in annual rainfall. Heavy rainfall (more than 90th percentile) in summer exhibits a marked downward trend mainly in the basin, which makes it possible for flooding to abate along the Wei River. Light rainfall (less than 10th percentile) shows a prevailing increasing trend in summer, but a decreasing trend in other seasons. From north to south, the seasonal trends become clearer and stronger. In terms of management, more attention should be paid to autumn droughts in the Wei River Basin. A quantitative measurement of a trend for ITA is proposed. Comparison of the three methods endorses the ITA method. Moreover, the ITA shows many advantages, such as graphical results and for observing sub-trends. It is hoped that this study can provide support for water resources planning, for coping with droughts and floods and for future development of the ITA method.

Description: IFNλR1 is a member of the class II cytokine receptor family, and it associates with IL-10R2 to form a functional receptor complex, IFNλR. This receptor complex transduces signals from IFNλs (IFNλ1, IFNλ2 and IFNλ3), promoting antiviral and antiproliferative activities similar to those of type I IFNs. In an effort to further understand signal transduction through IFNλR1, we used bioinformatics analysis and identified a tumor necrosis factor receptor associated factor 6 (TRAF6)-binding motif in the intracellular domain of IFNλR1. In subsequent immunoprecipitation and GST pull-down assays, IFNλR1 was shown to immunoprecipitate with TRAF6 and was pulled down by GST-TRAF6. Endogenous IFNλR1 and TRAF-6 interaction implies that these proteins really interact in the cells. This interaction was abrogated upon mutation of the TRAF6-binding motif in IFNλR1. Furthermore, the interaction between IFNλR1 and TRAF6 inhibited TRAF6-induced NF-κB activation, likely due to a reduction in TRAF6 autoubiquitination. Moreover, co-expression of IFNλR1 with TRAF6 significantly increased the stability of IFNλR1, thereby prolonging its half-life and enhancing its steady-state level in cultured cells. J. Cell. Biochem. © 2012 Wiley Periodicals, Inc.

Description: Multiple data sets, mostly from satellite observations, are used to evaluate the performance of the Weather Research and Forecasting model with Chemistry (WRF-Chem) in simulating the distribution and evolution of aerosol, clouds, precipitation and chemistry during the dry season in South America. A 9-day WRF-Chem simulation with 36 km horizontal resolution is performed from 15 to 24 September 2006, during which frequent biomass burnings were observed. It is shown that the model reproduces the spatial distribution of aerosols produced by biomass burning and approximately captures convective transport of trace gases (e.g., CO and O3) into the upper troposphere. Surface precipitation is also in reasonable agreement with observation. The model simulations overestimate the magnitude of water vapor in the upper troposphere while the magnitude of cloud water content is lower than measurements from satellites, which may indicate problems in the cumulus and microphysical parameterizations. The model simulations capture temporal variations of outgoing longwave radiation at the top of atmosphere and downward shortwave radiation at the surface shown in the NASA GEWEX SRB data set. A sensitivity run at 4 km horizontal resolution shows similar results to the 36 km simulation, with a high bias of precipitation. The uncertainty and weakness in both satellite observations and model simulations are identified. This study demonstrates that satellite data are valuable to the evaluation of regional model simulations for climatologically important processes such as deep convection and biomass burning, especially in regions with little in situ observation.

Description: A fully coupled meteorology-chemistry-aerosol mesoscale model (WRF-Chem) is used to simulate a multiday biomass burning event in the dry season of South America. The effects of biomass burning aerosols on clouds and precipitation are described at both 36 km and 4 km horizontal resolutions. The dominant effect of the aerosols is to reduce the diurnal amplitude of convection by decreasing clouds and precipitation in the afternoon but increasing them at night, with the afternoon decrease greater than the nighttime increase on the daily mean. On average, the decrease of surface precipitation is about 5% (3%) and the amplitude of diurnal cycle is reduced by about 11% (5%) in the 36 km (4 km) simulations. Such a modulation of clouds and precipitation is primarily contributed by the aerosol radiative effect, i.e., their ability to scatter and absorb solar radiation. The aerosol microphysical effect as cloud condensation nuclei tends to act oppositely to the aerosol radiative effect but with a smaller magnitude, especially in the simulations at 36 km horizontal resolution. The 4 km resolution runs exhibit similar behaviors to the 36 km simulations, with a slightly stronger role of the aerosol microphysical effect relative to the aerosol radiative effect. We find another important effect of biomass burning aerosols. When uplifted into the upper troposphere by deep convection, they can significantly warm the upper troposphere through their local radiative heating effect and result in significant moistening in the upper troposphere, potentially affecting the water vapor transport from the troposphere to the stratosphere.

Description: Three new 3,6-dioxygenated diketopiperazines, lepistamides A–C ( 1 – 3 ), along with a known compound, diatretol ( 4 ), were isolated from the mycelial solid cultures of the basidiomycete Lepista sordida. Their structures were elucidated by spectroscopic means. The isolated diketopiperazines were evaluated for the cytotoxic activity against Astc-a-1, Bel 7402, and HeLa cell lines, and their biogenetic pathway was discussed.

Description: Conditional mediums (CMs) from glioma cells U87, GBM-8401, and C6 significantly induced iNOS protein and NO production by microglial cells BV-2 but without altering the cell viability or cell-cycle progression of BV2 microglia. Significant increases in intracellular peroxide by U87-CM and C6-CM were detected by a DCHF-DA assay, and vitamin (Vit) C and N -acetyl cysteine (NAC)-reduced intracellular peroxide levels elicited by CMs lead to inhibition of iNOS/NO production The extracellular signal-regulated kinase (ERK) inhibitor, U0126, and c-Jun N-terminal kinase (JNK) inhibitor, SP600125, suppressed U87-CM- and C6-CM-induced iNOS/NO production by respectively blocking phosphorylated ERK (pERK) and JNK (pJNK) protein expressions stimulated by U87-CM and C6-CM. Increased migration of U87 and C6 glioma cells by a co-culture with BV-2 microglial cells or adding the nitric oxide (NO) donor, sodium nitroprusside (SNP) was observed, and that was blocked by adding an NO synthase (NOS) inhibitor, N -nitro l -arginine methyl ester (NAME). Contributions of ROS, pERK, and pJNK to the migration of glioma cells was further demonstrated in a transwell coculture system of U87 and C6 gliomas with BV-2 microglial cells. Furthermore, expressions of tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1 messenger (m)RNA in U87 and C6 cells were detected by an RT-PCR, and TNF-α and MCP-1 induced iNOS protein expression in time- and concentration-dependent manners. Neutralization of TNF-α or MCP-1 in U87-CM and C6-CM using a TNF-α or MCP-1 antibody inhibited iNOS protein expression, and increased intracellular peroxide by TNF-α or MCP-1 was identified in BV-2 cells. The reciprocal activation of glioma cells and microglia via ROS-dependent iNOS/NO elevation at least partially mediated by TNF-α and MCP-1 is elucidated. J. Cell. Physiol. 9999: XX–XX, 2014. © 2014 Wiley Periodicals, Inc.

Description: Increasing nitrogen (N) deposition or fertilization has been found to significantly affect carbon (C) cycling. However, a comprehensive understanding of how different C chemical components of plant, litter, and soil would respond to external N addition is still lacking. The present study herein compiled data of 1184 observations from 53 individual studies and conducted a meta-analysis of N addition effects on 18 variables related to C chemical compositions in terrestrial ecosystems. Results showed that plant lignin (+7.13%), plant protein (+25.94%), and soil lignin (+6.11%) were significantly increased by N addition, and plant hemicellulose (-4.39%) were significantly decreased, whereas plant fibre, plant cellulose, plant non-structural carbohydrate (NSC), litter lignin, and litter cellulose were not significantly changed. The effects of N addition on C chemical composition varied among different ecosystems/plant types and different forms of N addition. Increasing treatment duration did not significantly change the effects of N addition on the chemical composition of plant, litter and soil C. With increasing N addition rate, the effect of N addition on plant lignin, plant fibre, plant cellulose, and plant protein increased, while the effect of N addition on plant hemicellulose, plant NSC, and litter cellulose became more negative. Our meta-analysis provided a systematic evaluation of the responses of different C chemical components to N addition in the plant-litter-soil continuum. Results suggest that the change of plant and soil C chemical composition under N addition may be beneficial for ecosystem C sequestration and could affect ecosystem structure and function in the future. This article is protected by copyright. All rights reserved.

Description: [1]  The WRF-Chem model is used to examine aerosol impacts on precipitation over China during the East Asian summer monsoon (EASM). In the first EASM phase (May 6 - June 13), monsoonal rain band is located to the south of high aerosol areas. The surface cooling by the aerosol radiative effect induces an anti-cyclonic circulation in northern China, causing a precipitation decrease over southern China. The aerosol microphysical effect tends to broaden the precipitation region. In the second EASM phase (June 14 -August 5), the precipitation band jumps to northern China, where heavy pollution locates. By serving as CCN, the aerosol microphysical effect causes a reduction of local cloudiness and induces ascent to the north and descent to the south, leading to a precipitation shift from south to north. The aerosol radiative effect strengthens such a meridional asymmetry. Moisture budget analysis shows the aerosol-induced anomalies of precipitation in both phases are mainly contributed by the changes in vertical velocity associated with convection, while the horizontal advection of moisture plays a non-negligible role. Our study highlights that aerosol effects on EASM precipitation depend on the location of monsoon precipitation band and its relative location to aerosols, which may be a main factor contributed to the discrepancy in literature regarding to aerosol impacts on the so-called “southern flood and northern flood” over China.

Description: Autologous chondrocyte implantation (ACI) has emerged as a new approach to cartilage repair through the use of harvested chondrocytes. But the expansion of the chondrocytes from the donor tissue in vitro is restricted by limited cell numbers and dedifferentiation of chondrocytes. In this study, we used four types of hydrogels including agarose, alginate, Matrigel and collagen type I hydrogels to serve as cell substrates and investigated the effect on proliferation and phenotype maintenance of chondrocytes. As a substrate for monolayer culture, collagen facilitated cell expansion and effectively suppressed the dedifferentiation of chondrocytes, as evidenced by fluorescein diacetate / propidium iodide (FDA/PI), hematoxylin-eosin staining (HE), Safranin O, immunofluorescenceassay, biochemistry analysis and quantitative real-time polymerase chain reaction (qRT-PCR). Compared with that in agarose gels, alginate and Matrigel, collagen accelerated cell proliferation and enhanced the expression of cartilage specific genes such as ACAN, SOX9 and COLII more markedly. Furthermore, significantly lower expression of COL I (an indicator of dedifferentiation) and COL X (the chondrocyte hypertrophy marker) was present in collagen group than in other groups. This indicated that collagen substrate can better support chondrocyte growth and maintain cell phenotype, due to that it might serve as a cartilage-like ECM to provide adhesive site for chondrocytes. In summary, collagen hydrogel is a promising cell substrate for chondrocytes culture for ACI. This article is protected by copyright. All rights reserved

Description: Si 3 N 4 ceramics with different amount of Fe 5 Si 3 were prepared by adding FeSi 2 . Residual thermal stress distribution and elastic energy around Fe 5 Si 3 particles in various depths were calculated. Interface status between second phase particles and matrix was analyzed in terms of stress and energy. High tangential compressive stresses and low radial tensile stresses are generated along the surface of the ceramics. Elastic strain energy caused by unit interface is high around big particles in deep area of the ceramics. Microcracks around the interface preferentially tend to be generated in different area according to the relationship of thermal expansion coefficient. Residual stresses and microcracks around Fe 5 Si 3 particles have great influence on mechanical properties. Fracture toughness of Si 3 N 4 ceramics with similar Si 3 N 4 particle size distribution increases with amount of Fe 5 Si 3 , and fine Fe 5 Si 3 particles could enhance the strength of Si 3 N 4 ceramics. Si 3 N 4 ceramics with exceed 1.2GPa strength were prepared. This article is protected by copyright. All rights reserved.