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1Up-regulation of divalent metal transporter 1 in 6-hydroxydopamine intoxication is IRE/IRP dependent显示文摘铁在 Parkinson 的疾病(PD ) 起一个关键作用。substantia nigra (SN ) 的增加的铁内容在 PD 病人,和二价的金属 transporter 被发现了(DMT1 ) 1 被显示了在两个导致 MPTP 的 PD 模型和 PD 病人的 SN 起来调整。然而,位于 DMT1 起来规定下面的机制大部分是未知的。在现在的学习,我们观察到那在 6-hydroxydopamine ( 6-OHDA )的 SN 导致了 PD 老鼠,有铁的 DMT1 应答的元素(怒火, DMT1+IRE ),然而并非没有怒火( DMT1?IRE )的 DMT1 ,是起来调整的,建议那增加的 DMT1+IRE 表情可能在 PD 老鼠说明 nigral 铁累积。这可能性进一步被估计在一在里面 vitro 学习使用 6-OHDA-treated 和 DMT1+IRE-over-expressing MES23.5 房间。在 6-OHDA-treated MES23.5 房间,增加了铁规章的蛋白质(IRP ) 1 并且 IRP2 表示被观察,当 IRP 的 silencing 戏剧性地减少了时 6-OHDA-induced DMT1+IRE 起来规定。有 N-acetyl-L-cysteine 的预告的处理充分由 6-OHDA-induced 的抑制压制了 IRP 起来规定氧化应力。增加的 DMT1+IRE 表示由 MES23.5 房间导致了增加的铁流入。我们的数据提供 DMT1+IRE 起来规定能说明细胞内部的氧化应力和那增加了的 6-OHDA-induced 开始的 IRE/IRP-dependent 6-OHDA-induced 铁累积的直接证据细胞内部的铁的层次导致加重的氧化应力。这研究的结果提供在 PD 的处理支持抗氧化剂的使用的新奇证据,旨在禁止由 DMT1 表示的规定的铁累积。Hong Jiang Ning Song Huamin Xu Shuzhen Zhang Jun Wang Junxia Xie 2010Cell Research2010,20,3:25
2Integration of Metabolomics and Subcellular Organelle Expression Microarray to Increase Understanding the Organic Acid Changes in Post-harvest Citrus Fruit显示文摘Citric acid plays an important role in fresh fruit favor and its adaptability to post-harvest storage conditions.In order to explore organic acid regulatory mechanisms in post-harvest citrus fruit,systematic biological analyses were conducted on stored Hirado Buntan Pummelo(HBP;Citrus grandis)fruits.High-performance capillary electrophoresis,subcellular organelle expression microarray,real-time quantitative reverse transcription polymerase chain reaction,gas chromatography mass spectrometry(GC-MS),and conventional physiological and biochemical analyses were undertaken.The results showed that the concentration of organic acids in HBP underwent a regular fuctuation.GC-MS-based metabolic profling indicated that succinic acid,g-aminobutyric acid(GABA),and glutamine contents increased,but 2-oxoglutaric acid content declined,which further confrmed that the GABA shunt may have some regulatory roles in organic acid catabolism processes.In addition,the concentration of organic acids was signifcantly correlated with senescence-related physiological processes,such as hydrogen peroxide content as well as superoxide dismutase and peroxidase activities,which showed that organic acids could be regarded as important parameters for measuring citrus fruit post-harvest senescence processes.Xiaohua Sun Andan Zhu Shuzhen Liu Ling Sheng Qiaoli Ma Li Zhang Elsayed Mohamed Elsayed Nishawy Yunliu Zeng Juan Xu Zhaocheng Ma Yunjiang Cheng Xiuxin Deng 2013Journal of Integrative Plant Biology2013,55,11:14
3Effects of maize root exudates and organic acids on the desorption of phenanthrene from soils显示文摘The eects of maize root exudates and low-molecular-weight-organic anions (LMWOAs) on the desorption of phenanthrene from eight artificially contaminated soils were evaluated. A significant negative correlation was observed between the amounts of phenanthrene desorbed and the soil organic carbon (SOC) contents (P < 0.01), and the inuences of soil pH and clay content on phenanthrene desorption were insignificant (P > 0.1). Neither maize root exudates nor oxalate and citrate anions inuenced desorption of phenanthrene with the addition of NaN3. A faster phenanthrene desorption occurred without the addition of NaN3 in the presence of maize root exudates than oxalate or citrate due to the enhanced degradation by root exudates. Without the addition of NaN3, oxalate or citrate at dierent concentrations could inhibit phenanthrene desorption to dierent extents and the inhibiting eect by citrate was more significant than by oxalate. This study leads to the conclusion that maize root exudates can not enhance the desorption under abiotic condition with the addition of NaN3 and can promote the desorption of phenanthrene in soils without the addition of NaN3.ZHU Yanhong, ZHANG Shuzhen, HUANG Honglin, WEN Bei State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. 2009Journal of Environmental Sciences2009,21,7:14
4The classification and assessment of freeze-thaw erosion in Tibet显示文摘Freeze-thaw erosion is the third largest soil erosion type after water erosion and wind erosion. Restricted by many factors, few researches on freeze-thaw erosion have so far been done at home and abroad, especially those on the assessment method of freeze-thaw erosion. Based on the comprehensive analysis of impact factors of free-thaw erosion, this paper chooses six indexes, including the annual temperature range, annual precipitation, slope, aspect, vegetation and soil, to build the model for relative classification of freeze-thaw erosion using weighted and additive methods, and realizes the relative classification of the freeze-thaw erosion in Tibet with the support of GIS software. Then a synthetic assessment of freeze-thaw erosion in Tibet has been carried out according to the relative classification result. The result shows that the distribution of freeze-thaw eroded area is very extensive in Tibet, accounting for 55.3% of the total local land area; the spatial differentiation of freeze-thaw erosion with different intensities is obvious; and the difference in distribution among different regions is also obvious.ZHANG Jianguo LIU Shuzhen YANG Siquan 2007Journal of Geographical Sciences2007,17,2:12
5Ore-forming event and geodynamic setting of molybdenum deposit at Wenquan in Gansu Province,Western Qinling显示文摘The Wenquan molybdenum deposit is associated with a Triassic granite in this area.The Wenquan granite is enriched in LILE and LREE,poor in HFSE,and has significantly higher contents of alkali(K2O+Na2O) and Sr,Ba than those of the island arc volcanic rocks.These geochemical characteristics are similar to post-collisional granites in high K calc-alkaline series.Studies of major elements,trace elements,REEs and chronology of the Wenquan pluton show that,in the geodynamic transition stage of continent-continent convergence to extension,the partial melting of the enriched lithospheric mantle generated the basaltic magma and triggered the partial melting of the thickened lower crust which produceded the acidic magma,and the Wenquan pluton was formed by mixing of the two magmas.Molybdenite Re-Os isotopic dating gave Os model ages of 212.7±2.6 Ma to 215.1±2.6 Ma with a weighted mean of 214.1±1.1 Ma,and an Re-Os isochron age of 214.4±7.1 Ma.These ages are close to K-Ar ages(223 to 226 Ma) and a SHRIMP zircon U-Pb age(223±7 Ma) for the Wenquan granite within the error range,but relatively younger.This implies that the Mo mineralization occurred in a late stage of the magmatic intrusion,and the metallogenesis took place in the transition stage from syn-collision to post-collision in the tectonic setting of the Qinling Orogenic Belt(QOB) after continental collision be-tween the North China Block(NCB) and the South China Block(SCB).This process is also corre-sponding to the geological events of metamorphism and deformation in South Qinling,closure of the Mian-Lue oceanic basin,and exhumation of the Dabie-Sulu ultrahigh-pressure metamorphic rocks.The large-scale continent-continent collision between NCB and SCB in the middle Triassic triggered sig-nificant crustal thickening and exhumation of subducted slab.In the late Triassic,the tectonic setting was transformed to the transition stage from collision to extension.Materials from the asthenospheric mantle would ascend into the root of the lower crust,which could induce partial melting of the lower crust and generate Mo-enriched granitic magma.The ore-forming elements enriched in the fluid derived from the condensation and fraction of the magma resulted in the Mo mineralization.The Mo deposits in the QOB are mainly formed in two episodes,namely 220± Ma and 140± Ma.The two episodes of metal-logenesis were developed in the tectonic transition settings from compression to extension,but they were in the different stages of the tectonic evolution.The occurrence of the Wenquan Mo-bearing plu-ton indicates that the Triassic tectonic-magmatic belt of Western Qinling is another favorable region for Mo mineralization in the QOB.Therefore,it is significant to pay more attention to evaluation of the ore-forming potentiality in the Triassic granites in Western Qinling.ZHU LaiMin DING ZhenJu YAO ShuZhen ZHANG GuoWei SONG ShiGang QU WenJun GUO Bo LEE Ben 2009Chinese Science Bulletin2009,54,13:12
6Synthesis of CNT film on the surface of micro-pyramid array and its intense pulsed emission characteristics显示文摘We developed a new scheme to suppress the electric-field-screening effect in high growth density of a carbon nanotube(CNT) film during its intense pulsed emission.We synthesize the CNT film on a tridimensional surface(t-CNT film).The tridimensional surface includes wet etched silicon pyramids,and the Ni layer is electroless plated thereon.The intense pulsed emission characteristics of the t-CNT and planar-grown CNT(p-CNT) films were measured using a diode structure in single-pulse mode.The even turn-on field decreased from 5.5 V/μm for p-CNTs to 2.8 V/m for t-CNTs,and the peak emission current increased from 232 A for p-CNTs to 324 A for t-CNTs at a peak field intensity ~12.2 V/m.The peak current of the t-CNT film increased by ~39.7% over the p-CNT film.It is clear that the micro-pyramid array can effectively suppress the field screening effect to improve the electron-emission of CNT films.ZENG FanGuang LI Xin LIU WeiHua QIAO ShuZhen MA HuaLi ZHANG Rui XIA LianSheng CHEN Yi LIU XingGuang ZHANG Huang 2012Chinese Science Bulletin2012,57,14:10
7Improvement in the intense pulsed emission stability of grown CNT films via an electroless plated Ni layer显示文摘Carbon nanotube(CNT)films were grown on silicon wafers with and without a nickel layer(Si-CNT and Ni-CNT)via the pyrolysis of iron phthalocyanine.The nickel layer was prepared using the electroless plating method.To study the emission stability of Si-CNT and Ni-CNT cathodes during intense pulsed emission,emission characteristics were measured repeatedly with a diode structure using a Marx generator as a voltage source.For the peak values of the pulsed voltage,which were in the range between 1.62-1.66 MV(corresponding to electric field intensities between 11.57-11.85 V/μm),the first cycle emission current was 109.4 A for Si-CNT and 180.5 A for Ni-CNT.By comparing the normalized emission currents of the Si-CNT and Ni-CNT cathodes,the improvement in the emission stability can be easily quantified.The number of emission cycles necessary for the peak current to decay from 100%to 50%increased from^3 for Si-CNT to^11 for a Ni-CNT film.ZENG FanGuang LI Xin LIU WeiHua QIAO ShuZhen MA HuaLi ZHANG Rui XIA LianSheng CHEN Yi LIU XingGuang ZHANG Huang 2011Chinese Science Bulletin2011,56,22:7
8Accumulation and phytotoxicity of technical hexabromocyclododecane in maize显示文摘To investigate the accumulation and phytotoxicity of technical hexabromocyclododecane(HBCD)in maize,young seedlings were exposed to solutions of technical HBCD at different concentrations.The uptake kinetics showed that the HBCD concentration reached an apparent equilibrium within 96 hr,and the accumulation was much higher in roots than in shoots.HBCD accumulation in maize had a positive linear correlation with the exposure concentration.The accumulation of different diastereoisomers followed the orderγ-HBCD>β-HBCD>α-HBCD.Compared with their proportions in the technical HBCD exposure solution,the diastereoisomer contribution increased forβ-HBCD and decreased forγ-HBCD in both maize roots and shoots with exposure time,whereas the contribution ofα-HBCD increased in roots and decreased in shoots throughout the experimental period.These results suggest the diastereomer-specific accumulation and translocation of HBCD in maize.Inhibitory effects of HBCD on the early development of maize followed the order of germination rate>root biomass≥root elongation>shoot biomass≥shoot elongation.Hydroxyl radical(OH)and histone H2AX phosphorylation(γ-H2AX)were induced in maize by HBCD exposure,indicative of the generation of oxidative stress and DNA double-strand breaks in maize.An OH scavenger inhibited the expression ofγ-H2AX foci in both maize roots and shoots,which suggests the involvement of OH generation in the HBCD-induced DNA damage.The results of this study will offer useful information for a more comprehensive assessment of the environmental behavior and toxicity of technical HBCD.Tong Wu Honglin Huang Shuzhen Zhang 2016Journal of Environmental Sciences2016,28,4:7
9Effect of feeding Lactobacillus plantarum P-8 on the faecal microbiota of broiler chickens exposed to lincomycin显示文摘Poultry and eggs are nutritious and healthy foods that contain high-quality proteins and low levels of fat compared with other meats. Recent studies have shown that poultry performance is closely associated with colonic health. Antibiotics are commonly used in the poultry industry to control diseases and enhance survival rates. However, antibiotic use can also result in host gut dysbiosis and immune dysregulation. Such imbalances compromise poultry health and growth performance. Thus, our study investigated the effect of Lactobacillus(L.) plantarum P-8 on the gut microbiome of chickens co-inoculated with the antibiotic lincomycin. Principal coordinate analysis showed that L. plantarum P-8 treatment shifted the faecal bacterial population structure. At the metagenomic level, the Clusters of Orthologous Groups(COGs) functional categories of P, C, N and A were overrepresented in the probiotic group. Additionally, the relative gene abundances of metabolic pathways involved in flagellar assembly,bacterial chemotaxis, nitrogen metabolism, sulfur metabolism, cofactor and vitamin biosynthesis were also higher in the probiotic group than the control; in contrast genes related to galactose degradation,carbon fixation, multiple sugar transport systems and ribosomes were underrepresented in the probiotic group. Our data suggest that feeding L. plantarum P-8 has the potential to improve metabolic activity and nutrient utilization of poultry. Furthermore, the faecal antibiotic resistomes of the two groups could be separated using principal components analysis, indicating that the probiotic treatment may modulate the intestinal antibiotic resistance gene pool by changing the population structure of the gut microbiota.This study has provided interesting insights into the application of probiotics in the poultry industry.Pengfei Gao Qiangchuan Hou Lai-Yu Kwok Dongxue Huo Shuzhen Feng Heping Zhang 2017Science Bulletin2017,62,2:7
10Effects of Sini San used alone and in combination with fluoxetine on central and peripheral 5-HT levels in a rat model of depression显示文摘OBJECTIVE: To investigate the effects of Sini San and fluoxetine on the levels of central and peripheral 5-HT in a rat model of depression, and provide new insight into the treatment of depression with integrated Chinese-Western Medicine.METHODS: A rat model of depression was established by chronic mild stress(CMS). Model rats received either Sini San, fluoxetine, a combination of the two drugs, or no drug treatment. Healthy naive rats were used as controls. Open field and sucrose preference tests were used to assess depression-like behavior. ELISA and immunohistochemistry were used to determine central and peripheral levels of 5-HT.RESULTS: In the group with no drug treatment,central 5-HT expression decreased while peripheral5-HT concentrations increased as CMS continued.Four weeks after CMS, Sini San alone was less effective in reducing depression-like behavior than fluoxetine alone or in combination with Sini San,but combined use was more effective than fluoxetine alone. Eight weeks after CMS, Sini San alone or in combination with fluoxetine was more effective in reducing depression-like behavior than fluoxetine alone. Furthermore Sini San and fluoxetine used alone or in combination notably increased central 5-HT expression and decreased peripheral 5-HT levels in the rat model.CONCLUSION:The results of the present study indicate that there is a synergistic action between the two medicines in the treatment of depression. Sini San exhibited a relatively long lag before its effects were observed; however, by eight weeks the Traditional Chinese Medicine appeared at least as effective as fluoxetine. We suggest that Sini San can replace fluoxetine in the later stages of depression treatment to minimize side effects observed with long-term fluoxetine administration.Yubo Li Yuxiu Sun Xueling Ma Xiaoxing Xue Wenting Zhang Zhiqian Wu Yulin Ouyang Jianxin Chen Weiming Wang Shuzhen Guo Wei Wang 2013Journal of Traditional Chinese Medicine2013,33,5:6
11Toxic effects of chlortetracycline on maize growth,reactive oxygen species generation and the antioxidant response显示文摘The toxicity of chlortetracycline (CTC) on maize (Zea mays L.) growth and reactive oxygen species (ROS) generation was studied.The root and shoot lengths and fresh weights of maize seedlings were inhibited by CTC treatment (p < 0.05).Root length was more sensitive than other parameters with the EC 10 value of 0.064 mg/L.The spin trapping technique followed by electron paramagnetic resonance (EPR) analysis was used to quantify the ROS production.The ROS generated in maize roots after exposure to CTC was identified as hydroxyl radical (·OH).The EPR signal intensity correlated positively with the logarithm of CTC concentrations exposed (p < 0.05).The dynamic changes of malondialdehyde (MDA) contents and the antioxidative enzyme activities in maize roots were also determined.As compared to the control group,CTC was found to significantly increase MDA content.Treatment of maize roots with the ·OH scavenger sodium benzoate (SB) reduced the MDA content and enhanced the antioxidative enzyme activities.The results demonstrated the harmfulness of CTC at high dose to maize in the early developmental stage,and clarified that the inducement of ·OH is one of the mechanisms of CTC toxicity.Bei Wen Yu Liu Peng Wang Tong WU Shuzhen Zhang Xiaoquan Shan Jingfen Lu 2012Journal of Environmental Sciences2012,24,6:6
12Effects of purified zearalenone on selected immunological measurements of blood in post-weaning gilts显示文摘Zearalenone(ZEA), an estrogenic mycotoxin, is produced mainly by Fusarium fungi. Previous studies have indicated that acute ZEA exposure induced various damages in different species; however, its transparent hematotoxicity in female piglets at dietary levels of 1.1 to 3.2 mg/kg has not been shown. The present study was conducted to investigate the effects of dietary ZEA(1.1—3.2 mg/kg) on hematology, T lymphocyte subset, immunoglobulin, antibody titer, lymphocyte proliferation rate(LPR), and interleukin-2(IL-2) in peripheral blood of post-weaning gilts. A total of 20 female piglets(Landrace × Yorkshire × Duroc),weaned at 42 d with an average body weight of 10.36 ± 1.21 kg were used in the study. Female piglets were kept in a temperature controlled room, divided into four treatments, and fed a diet based on corn-soybean meal-fishmeal-whey, with an addition of 0, 1.1, 2.0, or3.2 mg/kg purified ZEA for 18 d ad libitum. Feed intake and refusal were measured daily and individual pigs were weighed weekly. Blood and serum samples were collected for selected immunological measurements. Female piglets fed different levels of dietary ZEA grew similarly with no difference in feed intake. Hematological values including leukocytes, platelets, lymphocytes, hematocrit, and mean corpuscular hemoglobin(MCH) decreased linearly(P < 0.05) as dietary ZEA increased. Female piglets fed diets containing 2.0 mg/kg ZEA or greater showed significantly decreased CD4+CD8+, CD4+, and CD4+/CD8^+ in comparison to the control(P < 0.05), whereas CD8^+ was significantly increased(P = 0.026) in the gilts which were fed the diet containing 3.2 mg/kg ZEA. Serum immunoglobulin G(IgG) and the antibody titer on d 18 were reduced linearly as dietary ZEA levels increased(P < 0.001). Linear decrease in LPR was observed(P < 0.05). Female piglets fed diets containing 2.0 mg/kg ZEA or more showed significantly decreased IL-2 in comparison to the control(P < 0.05). The results suggested that dietary ZEA at the levels of 1.1 to 3.2 mg/kg can induce different degrees of hematotoxicity and negatively affect immune function in female piglets.Lijie Yang Weiren Yang Qiang Feng Libo Huang Guiguo Zhang Faxiao Liu Shuzhen Jiang Zaibin Yang 2016Animal Nutrition2016,,3:5
13Simultaneous determination of brominated phenols in soils显示文摘Brominated phenols(BPs),a widely used group of emerging flame retardants,are important environmental contaminants and exhibit endocrine disrupting potential.Method for simultaneous determination of tetrabromobisphenol A(TBBPA),tribromophenol(TBP),dibromophenols(DBPs)and monobromophenols(MBPs)in soils using gas chromatography-mass spectrometry analysis(GC/MS)was successfully developed.Cleanup methods for soil extracts including several solid-phase extraction cartridges and diferent elution solvents were compared and optimized.Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils.Derivatization conditions were tested and the optimal conditions were obtained with 20μL silylation reagent at room temperature.The chromatographic separation was optimized with diferent columns and DB-XLB column was selected for its excellent separation of the analytes.The limits of detection for the target compounds were from 0.04 to 0.19 ng/g.Mean recoveries of the compounds from spiked soils exceeded 84%with a good reproducibility,excepting that the recovery of 2-bromophenol was relatively poor(lower than 55%)due to its instability.The developed method was applied to the determination of the BPs in the soils collected from e-waste sites.The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected.To our knowledge,this is the first report for the simultaneous determination of TBBPA,TBP,DBPs and MBPs in soils.Wei Han Sen Wang Honglin Huang Lei Luo Shuzhen Zhang 2013Journal of Environmental Sciences2013,25,11:5
14152 W high-power blue diode laser operated at 447 nm显示文摘We demonstrate a high-power blue diode laser operated at 447 nm combining laser diodes using an optical fiber bundle. As many as 127 diode lasers at 447 nm were coupled into 400 μm/0.22 NA fibers using an aspherical lens group with different focus lengths. The bare fibers were mechanically bundled through high temperature ultraviolet adhesive after the coatings of the 127 fibers were stripped. The diameter of the fiber bundle was 6 mm. The total output power of such a bundle was 152 W with electro-optical conversion efficiency of 27.56%and the RMS power instability was less than ±1% within 3 h.Peng Wu Ling Zhang Haijuan Yu Xiandan Yuan Zhiyan Zhang Pengfei Zhao Shuzhen Zou Chaojian He Yaoyao Qi Yingying Yang Gang Li Xubao Wang Xuechun Lin 2017Journal of Semiconductors2017,38,7:4
15Development of highly glyphosate-tolerant tobacco by coexpression of glyphosate acetyltransferase gat and EPSPS G2-aroA genes显示文摘The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS).Glyphosate acetyltransferase(GAT)effectively detoxifies glyphosate by N-acetylation.With the aim of identifying a new strategy for development of glyphosate-tolerant crops,the plant expression vector pG2-GAT harboring gat and G2-aroA(encoding EPSPS)has been transformed into tobacco(Nicotiana tabacum)to develop novel plants with higher tolerance to glyphosate.Results from Southern and Western blotting analyses indicated that the target genes were integrated into tobacco chromosomes and expressed effectively at the protein level.Glyphosate tolerance was compared among transgenic tobacco plants containing gat,G2-aroA,or both genes.Plants containing both gat and G2-aroA genes were the most glyphosate-tolerant.This study has shown that a combination of different strategies may result in higher tolerance in transgenic crops,providing a new approach for development of glyphosate-tolerant crops.Baoqing Dun Xujing Wang Wei Lu Ming Chen Wei Zhang Shuzhen Ping Zhixing Wang Baoming Zhang Min Lin 2014The Crop Journal2014,2,Z1:4
16Determination of total arsenic by photo-decomposition of organoarsenic compounds and hydride generation electrothermal atomic absorption spectrometry显示文摘A method was developed for the determination of total arsenic concentration in less than ng/ml level by decomposition of organoarsenicals using photo -oxidation combined with in situ trapping of arsenic hydride on a palladium coated graphite tube with subsequent atomization and detection by AAS. The organoarsenicals include monomethylarsenic, dimethylarsenic, arsenobetaine, arsenocholine, o -aminobenzenarsenate and p -aminobenzenarsenate. The method is simple and sensitive. Detection limit was obtained from different arsenic compounds over the range from 0. 058 to 0.063 ng/ml as As (based on three times of the standard deviation of 10 blank measurements) and the relative standard deviations for ten replicate measurements were from 2.0 to 3.8%. The calibration curves of arsenic compounds including inorganic and organic arsenicals were linear over the range from 0.1 to 3.0 ng/ml as As. The recommended method has been applied to the determination of total arsenic in tap and lake water samples at ng/mlHan Hengbin, Liu Yanbing, Zhang Shuzhen Ni ZhemingResearch Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P. O. Box 2871, Beijing 100085, China 1993Journal of Environmental Sciences1993,5,1:4
17Numerical Investigation of a High-subsonic Axial-flow Compressor Rotor with Non-axisymmetric Hub Endwall显示文摘The major source of loss in modern compressors is the secondary loss.Non-axisymmetric endwall profile contouring is now a well established design methodology in axial flow turbines.However,flow development in axial compressors is differ from turbines,the effects of non-axisymmetric endwall to axial compressors requires flow analysis in detail.This paper presents both experimental and numerical data to deal with the application of a non-axisymmetric hub endwall in a high-subsonic axial-flow compressor.The aims of the experiment here were to make sure the numerically obtained flow fields is the physical mechanism responsible for the improvement in efficiency,due to the non-axisymmetric hub endwall.The computational results were first compared with available measured data of axisymmetric hub endwall.The results agreed well with the experimental data for estimation of the global performance.The coupled flow of the compressor rotor with non-axisymmetric hub endwall was simulated by a state-of-the-art multi-block flow solver.The non-axisymmetric hub endwall was designed for a subsonic compressor rotor with the help of sine and cosine functions.This type of non-axisymmetric hub endwall was found to have a significant improvement in efficiency of 0.45% approximately and a slightly increase for the total pressure ratio.The fundamental mechanisms of non-axisymmetric hub endwall and their effects on the subsonic axial-flow compressor endwall flow field were analyzed in detail.It is concluded that the non-axisymmetric endwall profiling,though not optimum,can mitigate the secondary flow in the vicinity of the hub endwall,resulting in the improvement of aerodynamic performance of the compressor rotor.Shuzhen Hu Xingen Lu Hongwu Zhang Junqiang Zhu Qiang Xu 2010Journal of Thermal Science2010,19,1:4
18Neuroprotective effect of Longshengzhi capsule following permanent middle cerebral artery occlusion in rats显示文摘Objective:Longshengzhi capsule(LSZC)is an optimized preparation based on the traditional Chinese Medicine formula Buyanghuanwu Decoction(BYHWD),and is approved by the China Food and Drug Administration for treating stroke-induced disability and vascular diseases.Herein,we examined the pharmacodynamics,anti-apoptotic and anti-oxidant actions,and potential mechanisms of action of LSZC following stroke in rats.Methods:Permanent middle cerebral artery occlusion(MCAO)was used as an ischemic stroke model.LSZC was administered intragastrically.We examined the survival rate,bodyweight,and neurological deficits in stroke rats.Brain infarct size was determined by 2,3,5-triphenyltetrazolium chloride staining.Brain pathology was examined using hematoxylin and eosin staining,Nissl staining,and TdT-mediated dUTP Nick-End Labeling staining.Malondialdehyde,catalase,superoxide dismutase,and glutathione levels were examined by commercial kits.Expression of Nrf2,heme oxygenase-1,Bax,Bcl-2,cleaved caspase-3,and caspase-3 proteins in brain tissue was measured by Western blot.Results:LSZC markedly improved the survival rate and bodyweight,and reduced infarct volume and neurological deficit scores,in MCAO stroke rats.LSZC also significantly attenuated oxidative stress,as indicated by decreased expression of malondialdehyde,and upregulation of Nrf2,heme oxygenase-1,catalase,superoxide dismutase,and glutathione.Moreover,LSZC significantly decreased apoptosis,including a decrease in Bax and cleaved caspase-3 expression,and an increase in Bcl-2,as well as a reduction in numbers of apoptotic neurons.Conclusion:LSZC treatment is neuroprotective against ischemic stroke,potentially via reducing oxidative stress and apoptosis.The Nrf2 and apoptotic signaling pathways may play important roles in the antioxidant and anti-apoptotic actions of LSZC.Xiaoli Sun Shuzhen Guo Yong Wang Bangze Fu Junjie Liu Yili Zhang Ruocong Yang Chun Li Jian Gao Li Gao Wei Wang 2020Journal of Traditional Chinese Medical Sciences2020,7,1:4
19Atrazine accumulation and toxic responses in maize Zea mays显示文摘Atrazine accumulation,oxidative stress,and defense response in maize seedlings exposed to extraneous atrazine were studied.Accumulation of atrazine in maize increased with increasing exposure concentration.The abscisic acid(ABA) content was positively correlated with the atrazine concentrations in maize roots and shoots(p < 0.05).Hydroxyl radical(.OH) in maize was determined in vivo with electron paramagnetic resonance spectroscopy.Its intensity was positively correlated with atrazine concentration in roots and shoots(p < 0.05),and higher level of.OH generated in roots than in shoots corresponded to the major accumulation of atrazine in roots.Superoxide dismutase,peroxidase and catalase in roots were up-regulated by atrazine exposure at 1 mg/L compared to the control and malondialdehyde content in roots was enhanced when atrazine exposure concentration reached 10 mg/L.These results suggested the exposure and accumulation of atrazine caused oxidative toxicity and antioxidant response in maize.Xiuying Li Tong Wu Honglin Huang Shuzhen Zhang 2012Journal of Environmental Sciences2012,24,2:4
20The Crustal Structure and Seismic Activity in North China显示文摘A layered crustal block model of North China has been constructed based on large amount of data from seismic sounding carried out in recent two decades. Some deep fault zones, such as the Zhangjiakou.Penglai and Tancheng-Lujiang fault zones, divide the upper crust of North China into three upper crustal terranes and nine bolcks. There are distinct differences in velocity and depth distributions, which reflects Cenozoic block faulting in North China in the process of formation of the deep structure. The upper crust shows the features of transition in isostatic adjustment. The existence of a low-velocity layer in the middle crust is characteristic of the crustal structure in North China. There seems to be an increase of rheology of the rocks in the lower crust and a persistence of stable regional stress field. The patterns of the Moho on two sides of the Yanshan-Taihang Mountains are different. The relief of the Moho around Beijing, Shijiazhuang and Guangrao where the deep faults join together shows a quadrantal distribution in some degree. The dynamic sources for seismic activity are the NE-SW horizontal compression and the diapirism of the upper mantle. The middle and upper crust, especially the layered block structure has the most significant effects on seismicity, and the occurrence of earthquakes is more closely related to them than to the Moho.Feng Rui Institute of Geophysics, State Seismological Bureau, Beijing Huang Guifang, Zheng Shuzhen, Wang Jun, Yan Huifen Geophysical Prospecting Party, State Seismological Bureau, Zhengzhou, Henan and Zhang Ruoshui Seismological Technique College, State Seismological Bureau, Yanjiao,Hebei 1989Acta Geologica Sinica(English Edition)1989,63,4:4
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