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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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Facilitating the oxygen redox chemistry in O3-type layered oxide cathode material for sodium-ion batteries by Fe substitution 被引量:1
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作者 Wei xiong Zhihao Liu +4 位作者 Wenjia cheng Jiagui Zheng Yi Zou xi chen Yang Liu 《Journal of Energy Chemistry》 2025年第4期59-67,共9页
Facilitating anion redox chemistry is an effective strategy to increase the capacity of layered oxides for sodium-ion batteries.Nevertheless,there remains a paucity of literature pertaining to the oxygen redox chemist... Facilitating anion redox chemistry is an effective strategy to increase the capacity of layered oxides for sodium-ion batteries.Nevertheless,there remains a paucity of literature pertaining to the oxygen redox chemistry of O3-type layered oxide cathode materials.This work systematically investigates the effect of Fe doping on the anionic oxygen redox chemistry and electrochemical reactions in O3-NaNi_(0.4)Cu_(0.1)Mn_(0.4)Ti_(0.1)O_(2).The results of the density functional theory(DFT)calculations indicate that the electrons of the O 2p occupy a higher energy level.In the ex-situ X-ray photoelectron spectrometer(XPS)of O 1s,the addition of Fe facilitates the lattice oxygen(O^(n-))to exhibit enhanced activity at 4.45 V.The in-situ X-ray diffraction(XRD)demonstrates that the doping of Fe effectively suppresses the Y phase transition at high voltages.Furthermore,the Galvanostatic Intermittent Titration Technique(GITT)data indicate that Fe doping significantly increases the Na~+migration rate at high voltages.Consequently,the substitution of Fe can elevate the cut-off voltage to 4.45 V,thereby facilitating electron migration from O^(2-).The redox of O^(2-)/O^(n-)(n<2)contributes to the overall capacity.O3-Na(Ni_(0.4)Cu_(0.1)Mn_(0.4)Ti_(0.1))_(0.92)Fe_(0.08)O_(2)provides an initial discharge specific capacity of 180.55 mA h g^(-1)and71.6%capacity retention at 0.5 C(1 C=240 mA g^(-1)).This work not only demonstrates the beneficial impact of Fe substitution for promoting the redox activity and reversibility of O^(2-)in 03-type layered oxides,but also guarantees the structural integrity of the cathode materials at high voltages(>4.2 V).It offers a novel avenue for investigating the anionic redox reaction in O3-type layered oxides to design advanced cathode materials. 展开更多
关键词 Sodium-ion battery Oxygen redox chemistry O3 layered oxide Doping modification Cathode material
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Retinal vessel density alteration after FS-LASIK for myopia with different axial lengths
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作者 Cai-Yun Fu Yan Zheng +9 位作者 Chang-Bin Zhai Hou-Bin Huang xi chen Yi-Ran Dong Ya-Bin Hu Wen Xu Jing Liu Yan Huang Ning Sun Xue-Yin chen 《International Journal of Ophthalmology(English edition)》 2025年第10期1936-1943,共8页
AIM:To compare the effects of different types of negative pressure suction on the macular and optic disc retinal vessel density(VD)in myopic patients with different axial lengths(ALs)undergoing femtosecond laser-assis... AIM:To compare the effects of different types of negative pressure suction on the macular and optic disc retinal vessel density(VD)in myopic patients with different axial lengths(ALs)undergoing femtosecond laser-assisted excimer laser in situ keratomileusis(FS-LASIK)by optical coherence tomography angiography(OCTA).METHODS:A prospective,nonrandomized,controlled study.Participants underwent FS-LASIK surgery were divided into the short AL group(SAL,22≤AL<26 mm)and the long AL group(LAL,26≤AL<28 mm)according to the different ALs.Further,the two groups were divided into subgroups according to the corneal flap using VisuMax or WaveLight FS200 femtosecond laser(FS)platform.All patients underwent OCTA before the surgery and 1-day/1-week/1-month after the surgery.ANOVA statistically analyzed data with two-factor repeated measurement in SPSS.RESULTS:Totally 108 participants(108 eyes,18–35y)were divided into SAL group[22 patients(4 males and 18 females)were treated with VisuMax,and 24(3 males and 21 females)were treated with WaveLight FS200]and LAL group[34 patients(4 males and 30 females)were treated with VisuMax,and 28 patients(6 males and 22 females)were treated with WaveLight FS200].In the LAL group,there was no significant difference in macular superficial capillary plexuses vessel density(SCP-VD)in the fovea and perifovea region,but compared with the VisuMax subgroup,SCP-VD in the parafoveal region(t=2.647,P=0.010)and the whole area(t=2.030,P=0.047)in WaveLight FS200 subgroup decreased at one day after the operation and increased to a preoperative level at 1-week and 1-month after operation.There was no significant difference between SCP-VD in the two SAL subgroups,neither of deep capillary plexuses vessel density(DCP-VD)and optic nerve head vessel density(ONH-VD)in the SAL and LAL groups.CONCLUSION:With the increase of AL and suction intensity,a transient decrease of SCP-VD in the macular region is observed at 1d postoperatively during FS-LASIK,and it increases to preoperative level at 1-week and 1-month postoperatively.However,the AL and suction intensity do not affect the macular DCP-VD and ONH-VD. 展开更多
关键词 optical coherence tomography angiography MYOPIA FS-LASIK axial length vessel density
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Acute Single and Joint Toxicity Effects of Pendimethalin and Fenitrothion on Zebrafish ( Danio rerio )
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作者 Rahma Mohamed Mahmoud Shiqi WEI +2 位作者 xi chen Mingxiao LI Shunlong MENG 《Agricultural Biotechnology》 2025年第6期22-24,共3页
In this study,the single and jiont acute toxicity effects of pendimethalin(herbicide)and fenitrothion(organophosphate insecticide)were investigated on juvenile zebrafish(Danio rerio)under semi-static conditions.Mortal... In this study,the single and jiont acute toxicity effects of pendimethalin(herbicide)and fenitrothion(organophosphate insecticide)were investigated on juvenile zebrafish(Danio rerio)under semi-static conditions.Mortality was assessed at 24,48,72,and 96 h.The study revealed that pendimethalin exhibited higher toxicity than fenitrothion.The 96-h LC 50 values were 0.477 mg/L for pendimethalin and 2.634 mg/L for fenitrothion.Joint exposure produced enhanced toxicity,with 96-h LC 50 values of 0.204 mg/L(pendimethalin equivalent)and 1.139 mg/L(fenitrothion equivalent).Regression analysis showed a significant positive correlation(p<0.05)between pesticide concentration and mortality,while toxicity indices confirmed synergistic interactions.These findings underscore the ecological risks posed by pesticide mixtures and highlight the importance of regulating pesticide use to safeguard aquatic organisms and maintain environmental sustainability. 展开更多
关键词 Acute toxicity Joint toxicity PENDIMETHALIN FENITROTHION Zebrafish(Danio rerio)
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Single and Joint Acute Toxicity Effects of Lambda-cyhalothrin and Cypermethrin on Nile tilapia ( Oreochromis niloticus ) Fingerlings
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作者 Meshack Chubwa Maguru Shiqi WEI +3 位作者 xi chen Mingxiao LI Shunlong MENG Emmanuel Godfrey Maneno 《Agricultural Biotechnology》 2025年第6期53-55,64,共4页
The extensive co-occurrence of pyrethroid insecticides such as lambda-cyhalothrin(LCT)and cypermethrin(CPM)in aquatic systems poses a potential risk,yet a significant research gap exists regarding their combined toxic... The extensive co-occurrence of pyrethroid insecticides such as lambda-cyhalothrin(LCT)and cypermethrin(CPM)in aquatic systems poses a potential risk,yet a significant research gap exists regarding their combined toxicological effects.In this study,the single and joint acute toxicity effects of lambda-cyhalothrin(LCT)and cypermethrin(CPM)on Nile tilapia fingerlings were investigated using 96-h bioassays.Results showed both were highly toxic,with LCT(96-h LC 50=66.53μg/L)being four-fold more potent than CPM(259.41μg/L).Regression analysis confirmed positive correlation(P<0.01)between pesticide concentration and observed mortality.The binary mixture exhibited synergistic effect with Additive Index(AI)>0,indicating combined effects exceeded the sum of their individual actions.This synergism likely stems from mutual inhibition of metabolic detoxification pathways,leading to increased internal concentrations and amplified neurotoxicity.Generally,this study confirmed that single-compound risk assessments dangerously underestimate pyrethroid mixture hazards,necessitating their inclusion in regulatory frameworks for accurate aquatic biodiversity protection. 展开更多
关键词 Acute toxicity Joint toxicity LAMBDA-CYHALOTHRIN CYPERMETHRIN Oreochromis niloticus
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Acute Single and Joint Toxicity Effects of Imidacloprid and Thiamethoxam on Zebrafish ( Danio Rerio )
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作者 Agnes Adu-Gyamfi Mingxiao LI +1 位作者 Shunlong MENG xi chen 《Agricultural Biotechnology》 2025年第3期36-39,共4页
This study attempted to assess the lethal concentration(96-h LC_(50))effects of imidacloprid(neonicotinoid pesticide),thiamethoxam(neonicotinoid pesticide),and their combination on juvenile Zebrafish(Danio rerio).Each... This study attempted to assess the lethal concentration(96-h LC_(50))effects of imidacloprid(neonicotinoid pesticide),thiamethoxam(neonicotinoid pesticide),and their combination on juvenile Zebrafish(Danio rerio).Each set of trials contained a control(de-chlorinated tap water),and the experiments were repeated three times.The fish(n=10)were randomly measured with an average length of(3.4±0.34)cm and weight of(1±0.1)g.The temperature was kept at 24℃.Experiments 1 and 2 were designed to investigate at the acute toxicity of imidacloprid and thiamethoxam on juvenile zebrafish(Danio rerio)respectively,whereas experiment 3 was aimed at the combined toxicity of IMI and THM on zebrafish.The tests followed the same study design,and each experiment used seven different logarithmic concentrations of imidacloprid insecticides(310.00,317.08,324.33,331.74,339.32,347.07,355.00 mg/L)and thiamethoxam(175.00,185.52,200.93,215.30,230.70,247.20,264.88 mg/L).The results show that THM is more toxic than IMI,with LC_(50)values of 190.34 mg/L for THM and 310.92 mg/L for IMI.Both individual toxicities showed a substantial positive connection(P<0.05)with confidence limits of 321.50-300.68 mg/L for IMI and 199.91-181.21 mg/L for THM.The joint toxicity test was carried out using the 96-h LC_(50)values of imidacloprid and thiamethoxam obtained in the individual acute toxicity trials at a 1:1 ratio.The Additive Index(AI)demonstrated that imidacloprid and thiamethoxam acted synergistically on D.rerio.As a matter of fact,more research is needed to better understand the impact of IMI and THM on other aquatic organisms and also create strategies to mitigate its harmful effects on aquatic life. 展开更多
关键词 Acute toxicity(LC_(50)) Joint toxicity IMIDACLOPRID THIAMETHOXAM Zebrafish(Danio rerio)
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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:28
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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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Hypoxia promotes pulmonary vascular remodeling via HIF-1α to regulate mitochondrial dynamics 被引量:8
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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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Use of Xinfeng capsule to treat abarticular pathologic changes in patients with rheumatoid arthritis 被引量:10
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作者 Jian Liu Yunxiang Cao +12 位作者 Chuanbing Huang Yuan Wang xi chen Wandong Zhang Guizhen Wang Haixia Fan Yao Ge Ruilian chen Ruikai Zong Yajun Qi Yue Sun Yifei Liu Fang Wang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第5期532-538,共7页
OBJECTIVE: To observe the influence of Xinfengcapsule(XFC) on abarticular pathologic changes(APCs) and other indices of patients with rheumatoid arthritis(RA) and explore the mechanism of action of XFC in improving su... OBJECTIVE: To observe the influence of Xinfengcapsule(XFC) on abarticular pathologic changes(APCs) and other indices of patients with rheumatoid arthritis(RA) and explore the mechanism of action of XFC in improving such changes.METHODS: Three-hundred RA patients were divided randomly into a treatment group(n=150) and control group(n=150). A normal control(NC)group(n=90) was also created. Changes in cardiac function, pulmonary function, anemia indices and platelet parameters of RA patients were measured.Curative effects of the two groups were compared,and comparison carried out with the NC group.RESULTS: In 300 RA patients, late diastolic peak flow velocity(A peak) was much higher(P<0.01)and early diastolic peak flow velocity(E peak), E/A,and left ventricular fraction shortening much lower(P<0.01) than those in the NC group. Vital capacity(VC), forced vital capacity in one second, forced vital capacity(FVC), maximal voluntary ventilation(MVV), maximal expiratory flow in 50% of VC(FEF50) and FEF75 were lowered remarkably(P<0.05 or P<0.01). Platelet count(PLT), plateletcrit(PCT) and mean platelet volume(MPV) increased markedly(P<0.05 or P<0.01), and hemoglobin(Hb)level decreased significantly(P<0.05). After XFC treatment, the A peak and PLT and PCT were much lower(P<0.05), and E/A and the number of red blood cells as well as Hb level were much higher(P<0.05), as were FVC, MVV and FEF50(P<0.05 or P<0.01), in the treatment group than those in the NC group. Total score of pain and swelling in joints,uric-acid level and high-sensitivity C-reactive protein level were much lower, and superoxide dismutase level as well as the number of CD4 +CD25+ regulation T cells(Treg) and CD4+CD25+CD127- Treg were much higher(P<0.05 or P<0.01)in the treatment group than those in the NC group.CONCLUSION: RA patients with pathologic changes in joints also suffer from lower cardiac and pulmonary functions and from parameters of anemia and platelet factors. XFC can improve the symptoms of RA patients, ameliorate their cardiac and pulmonary functions and reduce the parameters of anemia and platelet factors. XFC lowers the immune inflammatory reaction to improve APCs in RA patients. 展开更多
关键词 Arthritis rheumatoid Pathologic pro-cesses Xinfeng capsule
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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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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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Ceria nanoparticles: biomedical applications and toxicity 被引量:3
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作者 xiaoxuan FU Peng LI +7 位作者 xi chen Yuanyuan MA Rong WANG Wenxuan JI Jiakuo GU Bowen SHENG Yizhou WANG Zhuhong ZHANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2024年第5期361-388,共28页
Ceria nanoparticles(CeO_(2) NPs)have become popular materials in biomedical and industrial fields due to their potential applications in anti-oxidation,cancer therapy,photocatalytic degradation of pollutants,sensors,e... Ceria nanoparticles(CeO_(2) NPs)have become popular materials in biomedical and industrial fields due to their potential applications in anti-oxidation,cancer therapy,photocatalytic degradation of pollutants,sensors,etc.Many methods,including gas phase,solid phase,liquid phase,and the newly proposed green synthesis method,have been reported for the synthesis of CeO_(2) NPs.Due to the wide application of CeO_(2) NPs,concerns about their adverse impacts on human health have been raised.This review covers recent studies on the biomedical applications of CeO_(2) NPs,including their use in the treatment of various diseases(e.g.,Alzheimer's disease,ischemic stroke,retinal damage,chronic inflammation,and cancer).CeO_(2) NP toxicity is discussed in terms of the different systems of the human body(e.g.,cytotoxicity,genotoxicity,respiratory toxicity,neurotoxicity,and hepatotoxicity).This comprehensive review covers both fundamental discoveries and exploratory progress in CeO_(2) NP research that may lead to practical developments in the future. 展开更多
关键词 Ceria nanoparticle Synthetic method Biomedical application Oxidative stress TOXICITY
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Analysis and comparison of spatial interpolation methods for temperature data in Xinjiang Uygur Autonomous Region, China 被引量:5
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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:2
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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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Cath-KP,a novel peptide derived from frog skin,prevents oxidative stress damage in a Parkinson’s disease model 被引量:1
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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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