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Zirconium Aided Epitaxial Growth of InxSey on InP(111) Substrates Cheng
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作者 cheng Zheng Dapeng Zhao +8 位作者 xinqiang Cai Wantong Huang Fanqi Meng Qinghua Zhang Lin Tang xiaopeng Hu Lin Gu Shuai-Hua Ji xi chen 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第8期118-122,共5页
Layered material indium selenide(InxSey)is a promising candidate for building next-generation electronic and photonic devices.We report a zirconium aided MBE growth of this van der Waals material.When co-depositing zi... Layered material indium selenide(InxSey)is a promising candidate for building next-generation electronic and photonic devices.We report a zirconium aided MBE growth of this van der Waals material.When co-depositing zirconium and selenium onto an indium phosphide substrate with a substrate temperature of 400℃at a constant zirconium flux rate of 0.01 ML/min,the polymorphic Inx Sey layer emerges on top of the insulating ZrSe2 layer.Different archetypes,such as InSe,α-In2Se3 and α-In2Se3,are found in the InxSey layers.A negative magnetoresistance of 40%at 2 K under 9 T magnetic field is observed.Such an InxSeyZrSe2 heterostructure with good lattice-matching may serve as a candidate for device applications. 展开更多
关键词 material. ZIRCONIUM MATCHING
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Cath-KP,a novel peptide derived from frog skin,prevents oxidative stress damage in a Parkinson’s disease model
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作者 Huanpeng Lu Jinwei Chai +9 位作者 Zijian Xu Jiena Wu Songzhe He Hang Liao Peng Huang xiaowen Huang xi chen Haishan Jiang Shaogang Qu Xueqing Xu 《Zoological Research》 SCIE CSCD 2024年第1期108-124,共17页
Parkinson’s disease(PD)is a neurodegenerative condition that results in dyskinesia,with oxidative stress playing a pivotal role in its progression.Antioxidant peptides may thus present therapeutic potential for PD.In... Parkinson’s disease(PD)is a neurodegenerative condition that results in dyskinesia,with oxidative stress playing a pivotal role in its progression.Antioxidant peptides may thus present therapeutic potential for PD.In this study,a novel cathelicidin peptide(Cath-KP;GCSGRFCNLF NNRRPGRLTLIHRPGGDKRTSTGLIYV)was identified from the skin of the Asiatic painted frog(Kaloula pulchra).Structural analysis using circular dichroism and homology modeling revealed a uniqueαββconformation for Cath-KP.In vitro experiments,including free radical scavenging and ferric-reducing antioxidant analyses,confirmed its antioxidant properties.Using the 1-methyl-4-phenylpyridinium ion(MPP^(+))-induced dopamine cell line and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced PD mice,Cath-KP was found to penetrate cells and reach deep brain tissues,resulting in improved MPP^(+)-induced cell viability and reduced oxidative stress-induced damage by promoting antioxidant enzyme expression and alleviating mitochondrial and intracellular reactive oxygen species accumulation through Sirtuin-1(Sirt1)/Nuclear factor erythroid 2-related factor 2(Nrf2)pathway activation.Both focal adhesion kinase(FAK)and p38 were also identified as regulatory elements.In the MPTP-induced PD mice,Cath-KP administration increased the number of tyrosine hydroxylase(TH)-positive neurons,restored TH content,and ameliorated dyskinesia.To the best of our knowledge,this study is the first to report on a cathelicidin peptide demonstrating potent antioxidant and neuroprotective properties in a PD model by targeting oxidative stress.These findings expand the known functions of cathelicidins,and hold promise for the development of therapeutic agents for PD. 展开更多
关键词 Cath-KP PEPTIDE Parkinson’s disease Oxidative stress Neuroprotection
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LncRNA HCG18 promotes prostate cancer progression by regulating the miR-512-3p/HK-2 axis
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作者 Yaru Zhu Zhijing Wang +6 位作者 Haopeng Li Zhen Ren Tong Zi xin Qin Wenhuizi Sun xi chen Gang Wu 《Asian Journal of Urology》 CSCD 2024年第4期575-585,共11页
Objective:Long non-coding RNAs(lncRNAs)play an important role in tumor progression.Numerous studies show that lncRNAs are strongly associated with prostate cancer(PCa)progression.The aim of this study was to investiga... Objective:Long non-coding RNAs(lncRNAs)play an important role in tumor progression.Numerous studies show that lncRNAs are strongly associated with prostate cancer(PCa)progression.The aim of this study was to investigate the pathway through which lncRNA HCG18 regulates PCa progression by bioinformatics analysis and experiments.Methods:We compared HCG18 expression in PCa versus normal tissue and cells by data and cell lines,followed by comparing the changes in tumor cell proliferation,migration,and invasive ability after knockdown of HCG18.Then we searched for its downstream pathway by database and validated the pathway in vivo and in vitro.Results:HCG18 was highly expressed in PCa and has the ability to promote tumor proliferation,migration,and invasion;knockdown of HCG18 led to a decrease in the ability of cells to do so,which can be reversed by knockdown of miR-512-3p or overexpression of hexokinase 2.Conclusion:Our in vivo and in vitro experiments suggest that HCG18 can play a role in promoting PCa progression by blocking the inhibition of hexokinase 2 by miR-512-3p via sponge adsorption. 展开更多
关键词 Prostate cancer Long non-coding RNA MicroRNA Hexokinase-2 Warburg effect GLYCOLYSIS
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Plastic flow and interfacial bonding behaviors of embedded linear friction welding process:Numerical simulation combined with thermophysical experiment
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作者 Tiejun MA Zhenguo GUO +6 位作者 xiawei YANG Junlong JIN xi chen Jun TAO Wenya LI Achilles VAIRIS Liukuan YU 《Chinese Journal of Aeronautics》 2025年第1期87-98,共12页
In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components ... In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components in aircraft.The interfacial plastic flow behavior and bonding mechanism of this process were investigated by a developed coupling EulerianLagrangian numerical model using software ABAQUS and a novel thermo-physical simulation method with designed embedded hot compression specimen.In addition,the formation mechanism and control method of welding defects caused by uneven plastic flow were discussed.The results reveal that the plastic flow along oscillating direction of this process is even and sufficient.In the direction perpendicular to oscillation,thermo-plastic metals mainly flow downward along welding interface under coupling of shear stress and interfacial pressure,resulting in the interfacial plastic zone shown as an inverted“V”shape.The upward plastic flow in this direction is relatively weak,and only a small amount of flash is extruded from top of joint.Moreover,the wedge block and welding components at top of joint are always in un-steady friction stage,leading to nonuniform temperature field distribution and un-welded defects.According to the results of numerical simulation,high oscillating frequency combined with low pressure and small amplitude is considered as appropriate parameter selection scheme to improve the upward interfacial plastic flow at top of joint and suppress the un-welded defects.The results of thermo-physical simulation illustrate that continuous dynamic recrystallization(CDRX)induces the bonding of interface,accompanying by intense dislocation movement and creation of many low-angle grain boundaries.In the interfacial bonding area,grain orientation is random with relatively low texture density(5.0 mud)owing to CDRX. 展开更多
关键词 Embedded linear friction welding Plastic flow Interfacial bonding behavior Numerical simulation Thermo-physical simulation Temperature field Dynamic recrystallization
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Inhibitory effect of arsenic trioxide on angiogenesis and expression of vascular endothelial growth factor in gastric cancer 被引量:48
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作者 Yan-Feng xiao Shan-xi Liu +2 位作者 De-Dong Wu xi chen Li-Fen Ren 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第36期5780-5786,共7页
AIM: To investigate the inhibitory effect of As2O3 on angiogenesis of tumor and expression of vascular endothelial growth factor (VEGF) in tumor cells in vivo and in vitro. METHODS: The solid tumor model was formed in... AIM: To investigate the inhibitory effect of As2O3 on angiogenesis of tumor and expression of vascular endothelial growth factor (VEGF) in tumor cells in vivo and in vitro. METHODS: The solid tumor model was formed in nude mice with the gastric cancer cell line SGC-7901. The animals were randomly divided into three groups. As2O3 was injected into the arsenic-treated groups (2.5 mg/kg and 5 mg/kg) and the same volume of saline solution was injected into the control group. Microvessel density (MVD) and expression of VEGF were detected with immunofluorescence laser confocal technology. Further expression of VEGF protein and VEGF mRNA was measured with Western bloting and fluorescence quantitative RT- PCR in SGC-7901 cells treated with As2O3. RESULTS: In nude mice, after treatment with 5 mg/kg and 2.5 mg/kg As2O3 respectively, about 50% and 30% tumor growth inhibition were observed correspondingly (P < 0.05, P < 0.05). Decrease in MVD appeared in As2O3-treated tumors compared with control group (P < 0.001, P < 0.001). MVD in tumors was significantly lower in 5 mg/kg group than in 2.5 mg/kg group (P < 0.01). The fluorescence intensity levels of VEGF in tumor cells were significantly lowered in the arsenic-treated groups (P < 0.01, P < 0.01). The fluorescence intensity level of VEGF in 5 mg/kg group was lower than that in 2.5 mg/ kg group (P < 0.01). In vitro, the expression of VEGF protein decreased in dose- and time-dependent manner after the treatment with As2O3, but in VEGF mRNA no significant difference was found between the control group and the treated groups. CONCLUSION: As2O3 can inhibit solid tumor growth by inhibiting the formation of new blood vessels. One of the mechanisms is that As2O3 can inhibit VEGF protein expression. 展开更多
关键词 Arsenic trioxide Vascular endothelial growth factor ANGIOGENESIS Tumor growth inhibition
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Effect of arsenic trioxide on vascular endothelial cell proliferation and expression of vascular endothelial growth factor receptors Flt-1 and KDR in gastric cancer in nude mice 被引量:28
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作者 Yan-Feng xiao De-Dong Wu +2 位作者 Shan-xi Liu xi chen Li-Fen Ren 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6498-6505,共8页
AIM: To investigate the effect of arsenic trioxide (As2O3) on expression of vascular endothelial growth factor receptor-1 (VEGFR-1, Flt-1) and VEGFR-2 (KDR) in human gastric tumor cells and proliferation of vas... AIM: To investigate the effect of arsenic trioxide (As2O3) on expression of vascular endothelial growth factor receptor-1 (VEGFR-1, Flt-1) and VEGFR-2 (KDR) in human gastric tumor cells and proliferation of vascular endothelial cells.METHODS: The solid tumor model was formed in nude mice with the gastric cancer cell line SGC-7901. The animals were treated with As2O3. Microvessel density (MVD) and expression of Flt-1 and KDR were detected by immunofluorescence laser confocal microscopy. SGC-7901 cells were treated respectively by exogenous recombinant human VEGF165 or VEGF165 + As2O3. Cell viability was measured by MTT assay. Cell viability of ECV304 cells was measured by MTT assay, and cell cycle and apoptosis were analyzed using flow cytometry.RESULTS: The tumor growth inhibition was 30.33% and 50.85%, respectively, in mice treated with As2O3 2.5 and 5 mg/kg. MVD was significantly lower in arsenic-treated mice than in the control group. The fluorescence intensity levels of Flt-1 and KDR were significantly less in the arsenic-treated mice than in the control group. VEGF165 may accelerate growth of SGC7901 cells, but As2O3 may disturb the stimulating effect of VEGF165. ECV304 cell growth was suppressed by 76.51%, 71.09% and 61.49% after 48 h treatment with As2O3 at 0.5, 2.5 and 5 μmol/L, respectively. Early apoptosis in the As2O3- treated mice was 2.88-5.1 times higher than that in the controls, and late apoptosis was 1.17-1.67 times higher than that in the controls.CONCLUSION: Our results showed that As2O3 delays tumor growth, inhibits MVD, down-regulates Flt-1 and KDR expression, and disturbs the stimulating effect of VEGF165 on the growth of SGC7901 cells. These results suggest that As2O3 might delay growth of gastric tumors through inhibiting the paracrine and autocrine pathways of VEGF/VEGFRs. 展开更多
关键词 Arsenic trioxide Gastric tumor Fit-1 Tumor growth inhibition
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Mucosa repair mechanisms of Tong-Xie-Yao-Fang mediated by CRH-R2 in murine,dextran sulfate sodium-induced colitis 被引量:10
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作者 Shan-Shan Gong Yi-Hong Fan +5 位作者 Shi-Yi Wang Qing-Qing Han Bin Lv Yi Xu xi chen Yao-Er He 《World Journal of Gastroenterology》 SCIE CAS 2018年第16期1766-1778,共13页
AIM To explore the significance of corticotropin-releasing hormone(CRH)-receptor(R)2 in mucosal healing of dextran sulfate sodium(DSS)-induced colitis and the effect of Tong-Xie-Yao-Fang(TXYF) on CRH-R2 expression and... AIM To explore the significance of corticotropin-releasing hormone(CRH)-receptor(R)2 in mucosal healing of dextran sulfate sodium(DSS)-induced colitis and the effect of Tong-Xie-Yao-Fang(TXYF) on CRH-R2 expression and regulation.METHODS Ulcerative colitis was induced in mice by administration of 3%(w/v) DSS for 7 d. Once the model was established,mice were administered urocortin-2(30 μg/kg), a peptide which binds exclusively to CRH-R2, or various doses of aqueous TXYF extracts(2.8-11.2 g/kg), a CRH-R2 antagonist Astressin(Ast)2B(20 μg/kg), Ast2B + Ucn2, or Ast2B with various doses of aqueous TXYF extracts for 9 d. Colonic mucosal permeability was then evaluated by measuring the fluorescence intensity in serum. The colitis disease activity index(DAI), histology, body weight loss and colon length were assessed to evaluate the condition of colitis. Terminal deoxynucleotidyl transferase d UTP nick-end labeling was used to detect apoptosis of the intestinal epithelial cells. The expression level of Ki-67 represented the proliferation of colonic epithelial cells and was detected by immunohistochemistry. The expression levels of inflammation cytokines IL-6, TNF-α and CXCL-1 were examined in colon tissues using real-time PCR and ELISA kits.RESULTS Compared with the DSS group, mice treated with the CRH-R2 antagonist Ast2B showed greater loss of body weight, shorter colon lengths(4.90 ± 0.32 vs 6.21 ± 0.34 cm, P < 0.05), and higher DAI(3.61 ± 0.53 vs 2.42 ± 0.32, P < 0.05) and histological scores(11.50 ± 1.05 vs 8.33 ± 1.03, P < 0.05). Additionally, the Ast2B group showed increased intestinal permeability(2.76 ± 0.11 μg/mL vs 1.47 ± 0.11 μg/mL, P < 0.001), improved secretion of inflammatory cytokines in colon tissue, and reduced colonic epithelial cell proliferation(4.97 ± 4.25 vs 22.51 ± 8.22, P < 0.05). Increased apoptosis(1422.39 ± 90.71 vs 983.01 ± 98.17, P < 0.001) was also demonstrated. The Ucn2 group demonstrated lower DAI(0.87 ± 0.55 vs 2.42 ± 0.32, P < 0.001) and histological scores(4.33 ± 1.50 vs 8.33 ± 1.03, P < 0.05). Diminished weight loss, longer colon length(9.58 ± 0.62 vs 6.21 ± 0.34 cm, P < 0.001), reduced intestinal permeability(0.75 ± 0.07 vs 1.47 ± 0.11 μg/mL, P < 0.001), inhibited secretion of inflammatory cytokines in colon tissue and increased colonic epithelial cell proliferation(90.04 ± 15.50 vs 22.51 ± 8.22, P < 0.01) were all observed. Reduced apoptosis(149.55 ± 21.68 vs 983.01 ± 98.17, P < 0.05) was also observed. However, significant statistical differences in the results of the Ast2 B group and Ast2 B + Ucn2 group were observed. TXYF was also found to ameliorate symptoms of DSS-induced colitis in mice and to promote mucosal repair like Ucn2. There were significant differences between the Ast2B + TXYF groups and the TXYF groups.CONCLUSION CRH-R2 activates the intestinal mucosal antiinflammatory response by regulating migration, proliferation and apoptosis of intestinal epithelial cells in colitisinduced mice, and plays an important antiinflammatory role. TXYF promotes mucosal repair in colitis mice by regulating CRH-R2. 展开更多
关键词 Tong-Xie-Yao-Fang Aqueous extracts Corticotropin-releasing hormone receptor 2 UROCORTIN 2 ASTRESSIN 2B Mucosal healing Ulcerative COLITIS
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Saline soil enzyme activities of four plant communities in Sangong River basin of Xinjiang,China 被引量:11
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作者 ZhengJun GUAN Qian LUO +4 位作者 xi chen xianWei FENG Zhixi TANG Wei WEI YuanRun ZHENG 《Journal of Arid Land》 SCIE CSCD 2014年第2期164-173,共10页
Soil enzyme activity plays an important role in the conversion of soil organic carbon into inorganic carbon, which is significant for the global carbon cycle. In this study, we investigated the soil enzyme activities ... Soil enzyme activity plays an important role in the conversion of soil organic carbon into inorganic carbon, which is significant for the global carbon cycle. In this study, we investigated the soil enzyme activities of two ligninolytic enzymes (peroxidase and polyphenol oxidase) and five non-ligninolytic enzymes (a-l,4-glucosidase (AG); 13-1,4-gluco- sidase (BG); N-acetyl-[3-glucosaminidase (NAG); ~3-D-cellobiosidase (CBH); and ^-xylosidase (BXYL)) in four plant communities of the Sangong River basin in Fukang, North Xinjiang, China. The four typical plant communities were dominated by Haloxylon ammodendron, Reaumuria soongonica, Salsola passerina, and Tamarix rarmosissima, respec- tively, with saline soils of varied alkalinity. The results showed that the soil peroxidase activity decreased seasonally. The activities of the five non-ligninolytic enzymes decreased with increasing soil depths, while those of the two ligninolytic enzymes did not show such a trend. In the four plant communities, BG had the highest activity among the five non-ligninolytic enzymes, and the activities of the two ligninolytic enzymes were higher than those of the four non-ligninolytic ones (AG, NAG, CBH, and BXYL). The community of H. ammodendron displayed the highest activity with respect to the two ligninolytic enzymes in most cases, but no significant differences were found among the four plant communities. The geometric mean of soil enzyme activities of the four plant communities was validated through an inde- pendently performed principal component analysis (PCA), which indicated that different plant communities had different soil enzyme activities. The correlation analysis showed that soil polyphenol oxidase activity was significantly positively correlated with the activities of the five non-ligninolytic enzymes. The soil pH value was positively correlated with the ac- tivities of all soil enzymes except peroxidase. Soil microbial carbon content also showed a significant positive correlation (P〈0.01) with the activities of all soil enzymes except polyphenol oxidase. The results suggested that the H. ammoden- dron community has the highest ability to utilize soil organic carbon, and glucoside could be the most extensively utilized non-ligninolytic carbon source in the saline soil of arid areas in Xinjiang. 展开更多
关键词 soil enzyme activity saline soil Haloxylon ammodendron Reaumuria soongonica Salsola passerina Tamafix rarmosissima
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Response of vegetation to temperature and precipitation in Xinjiang during the period of 1998-2009 被引量:10
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作者 xiaoMing CAO xi chen +1 位作者 AnMing BAO Quan WANG 《Journal of Arid Land》 SCIE 2011年第2期94-103,共10页
In this paper,10-day spatio-temporal response of vegetation to the change of temperature and precipitation in spring,summer,autumn and whole year during the period of 1998―2009 was analyzed based on the data of SPOT ... In this paper,10-day spatio-temporal response of vegetation to the change of temperature and precipitation in spring,summer,autumn and whole year during the period of 1998―2009 was analyzed based on the data of SPOT VEGETATION-NDVI and 10-day average temperature or precipitation from 54 meteorological stations in Xinjiang.The results show that the response of 10-day NDVI to temperature was more significant than that to precipitation,and the maximal response of vegetation to temperature and precipitation lagged for two 10-day periods.Seasonally,the effect of temperature and precipitation on vegetation NDVI was most marked in autumn,then in spring,and it was not significant in summer.The response of vegetation to 10-day change of meteorological factors was positive with a long affecting duration in spring,and it had a relatively short affecting duration in autumn and summer.Spatially,the 10-day maximal response of NDVI to temperature in northern Xinjiang was higher than that in southern Xinjiang.The correlation between the 10-day NDVI in whole year and the temperature in the 0-8th 10-day period was significantly higher than that between the annual NDVI and the annual temperature at all meteorological stations;the interannual change of NDVI was accordant well with the change of annual precipitation.However,the effect of precipitation within a year on NDVI was not strong.The results indicated that interannual change of temperature was not the dominant factor affecting the change of vegetation NDVI in Xinjiang,but the decrease of annual precipitation was the main factor resulting in the fluctuation of vegetation coverage.Ten-day average temperature was an important factor to promote vegetation growth in Xinjiang within a year,but the effect of precipitation on vegetation growth within a year was not strong. 展开更多
关键词 NDVI temperature PRECIPITATION correlation SCALE
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First Global Carbon Dioxide Maps Produced from Tan Sat Measurements 被引量:26
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作者 Dongxu YANG Yi LIU +3 位作者 Zhaonan CAI xi chen Lu YAO Daren LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第6期621-623,共3页
1.The need for global carbon monitoring from space and the TanSat mission Global warming is a major problem,for which carbon dioxide(CO2 )is the main greenhouse gas involved in heating the troposphere.However,the po... 1.The need for global carbon monitoring from space and the TanSat mission Global warming is a major problem,for which carbon dioxide(CO2 )is the main greenhouse gas involved in heating the troposphere.However,the poor availability of global CO2 measurements makes it difficult to estimate CO2 emissions accurately. 展开更多
关键词 OCO First Global Carbon Dioxide Maps Produced from Tan Sat Measurements
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Spatio-temporal pattern and changes of evapotranspiration in arid Central Asia and Xinjiang of China 被引量:8
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作者 xi chen BaiLian LI +2 位作者 Qin LI JunLi LI Saparnov ABDULLA 《Journal of Arid Land》 SCIE 2012年第1期105-112,共8页
Accurate inversion of land surface evapotranspiration (ET) in arid areas is of great significance for understanding global eco-hydrological process and exploring the spatio-temporal variation and ecological response... Accurate inversion of land surface evapotranspiration (ET) in arid areas is of great significance for understanding global eco-hydrological process and exploring the spatio-temporal variation and ecological response of water resources. It is also important in the functional evaluation of regional water cycle and water balance, as well as the rational allocation and management of water resources. This study, based on model validation analysis at varied scales in fiwe Central Asian countries and China's Xinjiang, developed an appropriate approach for ET inversion in arid lands. The actual ET during growing seasons of the study area was defined, and the changes in water participating in evaporation in regional water cycle were then educed. The results show the simulation error of SEBS (Surface Energy Balance System) model under cloud amount consideration was 1.34% at 30-m spatial scale, 2.75% at 1-km spatial scale and 6,37% at 4-kin spatial scale. ET inversion for 1980-2007 applying SEBS model in the study area indicates: (1) the evaporation depth (May-September) by land types descends in the order of waters (660.24 ram) 〉 cultivated land (464.66 mm) 〉 woodland (388.44 mm) 〉 urbanized land (168.16 mm) 〉 grassland (160.48 mm) 〉 unused land (83.08 mm); and (2) ET during the 2005 growing season in Xinjiang and Central Asia was 2,168.68x108 m3 (with an evaporation/precipitation ratio of 1.05) and 9,741.03x108 m3 (with an evaporation/precipitation ratio of 1.4), respectively. The results unveiled the spatio-temporal variation rules of ET process in arid areas, providing a reference for further research on the water cycle and water balance in similar arid regions. 展开更多
关键词 Evapotranspiration (ET) arid areas SEBS model remote sensing Central Asia Xinjiang of China
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Hypoxia promotes pulmonary vascular remodeling via HIF-1α to regulate mitochondrial dynamics 被引量:6
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作者 xi chen Jia-Mei YAO +5 位作者 xia FANG Cui ZHANG Yu-Shu YANG cheng-Ping HU Qiong chen Guang-Wei ZHONG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第12期855-871,共17页
Background Increasing research suggests that mitochondrial defect plays a major role in pulmonary hypertension(PH) pathogenesis. Mitochondrial dynamics and quality control have a central role in the maintenance of the... Background Increasing research suggests that mitochondrial defect plays a major role in pulmonary hypertension(PH) pathogenesis. Mitochondrial dynamics and quality control have a central role in the maintenance of the cell proliferation and apoptosis balance. However, the molecular mechanism underlying of this balance is still unknown. Methods To clarify the biological effects of hypoxic air exposure and hypoxia-inducible factor-1α(HIF-1α) on pulmonary arterial smooth muscle cell(PASMC) and pulmonary arterial hypertension rats, the cells were cultured in a hypoxic chamber under oxygen concentrations. Cell viability, reactive oxygen species level, cell death, mitochondrial morphology, mitochondrial membrane potential, mitochondrial function and mitochondrial biosynthesis, as well as fission-and fusion-related proteins, were measured under hypoxic conditions. In addition, rats were maintained under hypoxic conditions, and the right ventricular systolic pressure, right ventricular hypertrophy index and right ventricular weight/body weight ratio were examined and recorded. Further, we assessed the role of HIF-1α in the development and progression of PH using HIF-1α gene knockdown using small interfering RNA transfection. Mdivi-1 treatment was performed before hypoxia to inhibit dynamin-related protein 1(Drp1). Results We found that HIF-1α expression was increased during hypoxia, which was crucial for hypoxia-induced mitochondrial dysfunction and hypoxia-stimulated PASMCs proliferation and apoptosis. We also found that targeting mitochondrial fission Drp1 by mitochondrial division inhibitor Mdivi-1 was effective in PH model rats. The results showed that mitochondrial dynamics were involved in the pulmonary vascular remodeling under hypoxia in vivo and in vitro. Furthermore, HIF-1α also modulated mitochondrial dynamics in pulmonary vascular remodeling under hypoxia through directly regulating the expression of Drp1. Conclusions In conclusion, our data suggests that abnormal mitochondrial dynamics could be a marker for the early diagnosis of PH and monitoring disease progression. Further research is needed to study the signaling pathways that govern mitochondrial fission/fusion in PH. 展开更多
关键词 Dynamin-related protein 1 HYPOXIA Hypoxia-inducible factor-1α Mitochondrial dynamics Pulmonary vascular remodeling
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Development and application of rapid rehabilitation system for reconstruction of maxillofacial soft-tissue defects related to war and traumatic injuries 被引量:6
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作者 Shi-Zhu Bai Zhi-Hong Feng +4 位作者 Rui Gao Yan Dong Yun-Peng Bi Guo-Feng Wu xi chen 《Journal of Medical Colleges of PLA(China)》 CAS 2014年第1期59-65,共7页
Background: Maxillofacial war injuries usually cause severe facial organ defects and deformities, handicapping the patient's daily activities, even result in a tendency to commit suicide. The application of maxill... Background: Maxillofacial war injuries usually cause severe facial organ defects and deformities, handicapping the patient's daily activities, even result in a tendency to commit suicide. The application of maxillofacial prosthesis is an alternative to surgery in functional–aesthetic facial reconstruction. Computer aided design and computer aided manufacturing has opened up a new approach to the fabrication of maxillofacial prosthesis. An intelligentized rapid simulative design and manufacture system for prosthesis was developed to facilitate the prosthesis fabrication procedure.Methods: Maxillofacial prosthesis rapid simulation design and rapid fabrication system consists of three components: digital impression, intelligentized prosthesis designing, and rapid manufacturing. The patients' maxillofacial digital impressions were taken with Structured-light 3D scanner; and then the 3D model of prostheses and their negative molds could be designed in specific software; finally, with the resin molds fabricated by rapid prototyping machine, the prostheses could be produced directly and quickly.Results: Fifteen patients of maxillofacial defect caused by traumatic injuries received prosthesis rehabilitation provided by the established system. The contour of the prostheses coordinated properly with the appearance of the patients, and the uniform-thickness border sealed well to adjacent tissues. All the patients were satisfied with their prostheses.Conclusions: The rapid simulative rehabilitation system of maxillofacial defects has been approaching completion. It could provide advanced technological reservation for the Army in the issue of maxillofacial defect rehabilitation. 展开更多
关键词 CAD/CAM maxillofacial defect prosthesis design defect rehabilitation war and traumatic injuries
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Analysis and comparison of spatial interpolation methods for temperature data in Xinjiang Uygur Autonomous Region, China 被引量:4
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作者 Huixia Chai Weiming cheng +3 位作者 chenghu Zhou xi chen xiaoyi Ma Shangming Zhao 《Natural Science》 2011年第12期999-1010,共12页
Spatial interpolation methods are frequently used to estimate values of meteorological data in locations where they are not measured. However, very little research has been investigated the relative performance of dif... Spatial interpolation methods are frequently used to estimate values of meteorological data in locations where they are not measured. However, very little research has been investigated the relative performance of different interpolation methods in meteorological data of Xinjiang Uygur Autonomous Region (Xinjiang). Actually, it has importantly practical significance to as far as possibly improve the accuracy of interpolation results for meteorological data, especially in mountainous Xinjiang. There- fore, this paper focuses on the performance of different spatial interpolation methods for monthly temperature data in Xinjiang. The daily observed data of temperature are collected from 38 meteorological stations for the period 1960- 2004. Inverse distance weighting (IDW), ordinary kriging (OK), temperature lapse rate method (TLR) and multiple linear regressions (MLR) are selected as interpolated methods. Two rasterized methods, multiple regression plus space residual error and directly interpolated observed temperature (DIOT) data, are used to analyze and compare the performance of these interpolation methods respectively. Moreover, cross-validation is used to evaluate the performance of different spatial interpolation methods. The results are as follows: 1) The method of DIOT is unsuitable for the study area in this paper. 2) It is important to process the observed data by local regression model before the spatial interpolation. 3) The MLR-IDW is the optimum spatial interpolation method for the monthly mean temperature based on cross-validation. For the authors, the reliability of results and the influence of measurement accuracy, density, distribution and spatial variability on the accuracy of the interpolation methods will be tested and analyzed in the future. 展开更多
关键词 Spatial INTERPOLATION Method CROSS validation MONTHLY Mean Temperature XINJIANG UYGUR AUTONOMOUS Region
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Addition of peroxiredoxin 6 (PRDX6) to IVF fertilization medium maintains motility and longevity of human spermatozoa 被引量:1
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作者 TIEchenG SUN YANDONG ZHANG +5 位作者 JIANHUA LI HONG YU LINGLI SONG xiNPING SUN xi chen LI TIAN 《BIOCELL》 SCIE 2021年第3期705-710,共6页
This study aims to investigate the protective effects of peroxiredoxin 6 on the total motility and progressive motility of human spermatozoa.Semen samples with normal parameters were collected from 23 males and supple... This study aims to investigate the protective effects of peroxiredoxin 6 on the total motility and progressive motility of human spermatozoa.Semen samples with normal parameters were collected from 23 males and supplemented with different concentrations of peroxiredoxin 6.All the semen samples were measured according to the WHO 5th manual,and the motile spermatozoa were extracted using IVF fertilization medium supplemented with different peroxiredoxin 6 concentrations.Total motility and progressive motility were observed at different time-points of culture at room temperature.After peroxiredoxin 6 supplementation,all groups had a significant increase in total motility and progressive motility compared to the control group.The difference in total motility and progressive motility between the 0 and 10−7 mM groups was observed at 24 and 48 h of culture at room temperature.At 24 h,the total motility increased by 30%in the control group(16.03±11.91 vs.11.51±7.84),and progressive motility increased by 21%(10.53±9.4 vs.8.31±6.04).A similar trend was observed in the 48 h group.In addition,we also found that peroxiredoxin 6 had a well protective effect on sperm kinetic parameters at 10−7 mM.The findings of this study suggest that peroxiredoxin 6 can enhance sperm total motility and progressive motility in IVF fertilization medium.Peroxiredoxin 6 may have potential benefits for sperm preparation in assisted reproductive technology. 展开更多
关键词 Peroxiredoxin 6 Sperm motility Progressive motility Sperm kinetic parameters
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Giant saturation absorption of tungsten trioxide film prepared based on the seedless layer hydrothermal method 被引量:1
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作者 马晓光 胡芳珍 +4 位作者 陈希 王艺盟 郝晓剑 顾敏 张启明 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期286-290,共5页
Nonlinear materials have gained wide interest as saturable absorbers and pulse compression for pulsed laser applications due to their unique optical properties.This work investigates the third-order nonlinear phenomen... Nonlinear materials have gained wide interest as saturable absorbers and pulse compression for pulsed laser applications due to their unique optical properties.This work investigates the third-order nonlinear phenomenon of tungsten trioxide(WO_(3))thin films.The giant nonlinear absorption and nonlinear refractive index of WO_(3)thin films were characterized by Z-scan method at 800 nm.We experimentally observed the giant saturable absorption(SA)and nonlinear refractive index of WO_(3)thin films prepared by the seedless layer hydrothermal method,with SA coefficient being as high as-2.59×105cm·GW^(-1).The SA coefficient is at least one order of magnitude larger than those of the conventional semiconductors.The nonlinear refractive index n_(2)of WO_(3)film has been observed for the first time in recent studies and the corresponding coefficient can be up to 1.793 cm^(2)·GW^(-1).The large third-order nonlinear optical(NLO)response enables WO_(3)thin films to be promising candidates for optoelectronic and photonic applications in the near-infrared domain. 展开更多
关键词 tungsten trioxide Z-SCAN saturable absorption
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Letters and Visits System Optimization and Implementation
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作者 Mu Tao xi chen Dan Qian 《Journal of Software Engineering and Applications》 2024年第9期731-739,共9页
The letters and visits system plays a vital role in government work, serving as a crucial tool for supervising law enforcement and administrative conduct, ensuring public officials’ integrity, and promoting governanc... The letters and visits system plays a vital role in government work, serving as a crucial tool for supervising law enforcement and administrative conduct, ensuring public officials’ integrity, and promoting governance by law. As Chinese citizens’ political awareness grows, the volume of letters and visits has increased steadily. This paper reviews the current state of letters and visits information construction, identifies challenges and problems in system integration, presents integration ideas for existing systems, and proposes an innovative approach to letters and visits system integration. This research aims to provide valuable insights and guidance for other units undertaking similar system integration efforts. 展开更多
关键词 Letters and Visits INFORMATIZATION System Integration
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Existing Problems and Countermeasures of Rural Industry Development in Bijie Experimental Area 被引量:1
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作者 chengdong WANG xi chen +1 位作者 Qin GE Li xiAO 《Asian Agricultural Research》 2023年第11期27-30,34,共5页
The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industri... The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industrial scale,standardization,branding,and marketization,and strives to extend the industrial chain and enhance the value chain to achieve the prosperity of rural industries.In this study,it investigated the current situation of rural industry development in Bijie City(improving the quality and efficiency of characteristic industries,expanding the quantity and efficiency of agricultural products processing industry,recruiting and cultivating large business entities,expanding and strengthening the brand of agricultural products,and upgrading the rural tourism).Through analysis,it found that there are problems such as small scale of production enterprises,insufficient cultivation of independent brands,short industrial chain,low added value,weak market expansion ability,imperfect interest connection mechanism,and insufficient participation of farmers.Finally,it came up with countermeasures for the development of rural industries in Bijie City,including improving supporting facilities and building an extension base;strengthening leading enterprises and focus on deep processing;highlighting regional characteristics and paying close attention to the docking of production and marketing;enhancing the characteristic brand and strengthening the support of science and technology;promoting collaboration and support,and making innovation in the connection of interests. 展开更多
关键词 Rural industries Current development situation PROBLEMS COUNTERMEASURES Bijie Experimental Area
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高地下水水位冻土区梯形渠道衬砌冻胀破坏断裂力学模型
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作者 吴浪 肖旻 +3 位作者 席琛 崔浩 杨晓松 葛建锐 《水资源与水工程学报》 CSCD 北大核心 2024年第5期148-154,163,共8页
冻胀荷载作用下初始裂纹的形成、扩展导致衬砌结构的断裂是寒区衬砌渠道冻害的主要原因之一。在已有研究基础上,综合考虑地下水水位影响的梯形渠道冻胀力学分析方法及线弹性断裂力学理论,提出高地下水水位梯形渠道冻胀断裂力学分析框架... 冻胀荷载作用下初始裂纹的形成、扩展导致衬砌结构的断裂是寒区衬砌渠道冻害的主要原因之一。在已有研究基础上,综合考虑地下水水位影响的梯形渠道冻胀力学分析方法及线弹性断裂力学理论,提出高地下水水位梯形渠道冻胀断裂力学分析框架。该模型将衬砌结构表面初始裂纹的失稳扩展及开裂破坏简化为Ⅰ型断裂力学问题,并提出应力强度因子与危险截面位置的计算方法。以塔里木灌区某梯形渠道为原型分析地下水埋深w对衬砌各截面应力强度因子K_(FⅠ)(x)及合理板厚d r的影响规律。结果表明:地下水补给条件对K_(FⅠ)(x)的大小影响显著;当w减小时,K_(FⅠ)(x)呈非线性增大,此时渠道冻害风险也增大,与事实相符。地下水埋深越浅,保证结构安全所需衬砌板的合理厚度d r越大;当地下水埋深为3.0 m时,建议使用的合理板厚为9.0 cm。研究结果可为寒区渠道的抗冻胀设计提供科学依据。 展开更多
关键词 梯形渠道 冻土 冻胀 断裂力学模型 高地下水位 非线性分布
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Yiqi Huoxue Decoction modifies the expression of myocardial cytoskeleton-associated proteins by regulating the AMPK signaling pathway in H9c2 cells exposed to hypoxic conditions 被引量:1
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作者 Jiani Wu Shuwen Guo +7 位作者 Yuqin Zhang Jinghong Hu Wang'ou Lin Binyue Zhang xi chen Hui Wang Hanrong Mo Tianwei Zhan 《Journal of Traditional Chinese Medical Sciences》 2019年第2期164-174,共11页
Background:In myocardial ischemia,hypoxia leads to destruction of the cytoskeleton,and especially the imbalance of microtubule polymerization-depolymerization,which seriously affects the structure and function of card... Background:In myocardial ischemia,hypoxia leads to destruction of the cytoskeleton,and especially the imbalance of microtubule polymerization-depolymerization,which seriously affects the structure and function of cardiomyocytes.We previously showed that a Yiqi Huoxue Decoction (YQHX) improves mitochondrial function and decreases anti-oxidative effects in hypoxia-induced H9c2 cell injury.Therefore,in this study we investigated whether YQHX protects against hypoxia-induced damage by decreasing damage to the cardiac cytoskeleton.Methods:After reaching 70%-80% confluence,H9c2 cells were synchronized in serum-free Dulbecco's Modified Eagle Medium for 6 hours,then divided into control,model,and YQHX (100,200,400 μg/mL) groups,which were then grown in a hypoxic atmosphere for 12 hours.Cardiac cell viability was assessed using an xCELLigence system.The levels of lactate dehydrogenase,maleic dialdehyde,and superoxide dismutase in H9c2 cell supernatants were measured.Hoechst 33258 staining was employed to observe cardiac cell apoptosis.Confocal microscopy,immunofluorescence,and western blot analysis were performed to evaluate the protective effects of the YQHX against hypoxia-induced injury in the H9c2 cell line.Results:Cells that were pretreated with YQHX were more able to maintain their microtubule structure in the early stages of hypoxia and had better myocardial fitness in response to hypoxia compared with cells that were not pretreated.However,hypoxia-induced upregulation of α-tubulin and β-tubulin expression antagonized the protective effect of YQHX (100 μg/mL).In addition,YQHX (100 μg/mL) treatment significantly upregulated MAP4 protein expression (P =.003) and downregulated p-AMPKα protein expression (P <.001) compared with the model group.Conclusion:The results indicate that YQHX plays a role in protecting against oxidative stress injury and apoptosis in H9c2 cells.Notably,our results suggested that the YQHX could mitigate the damage to the cardiac cytoskeleton and the dysregulation of AMPK-related protein signaling pathways that are induced by hypoxia. 展开更多
关键词 Yiqi huoxue DECOCTION Hypoxia MYOCARDIAL CYTOSKELETON MICROTUBULES AMPK
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