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Single and Joint Acute Toxicity Effects of Glyphosate Isopropyl Amine Salt(GIS)and Atrazine(ATZ)on Juvenile Zebrafish(Danio rerio)
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作者 Emmanuel Godfrey Maneno Shiqi WEI +3 位作者 xi chen Mingxiao LI Shunlong MENG Meshack Chubwa Maguru 《Agricultural Biotechnology》 2026年第1期22-25,共4页
The widespread use of herbicides such as glyphosate isopropyl amine salt(GIS)and atrazine(ATZ)poses significant risks to aquatic ecosystems.This study investigated the single and joint acute toxicity of a 1:1 GIS-ATZ ... The widespread use of herbicides such as glyphosate isopropyl amine salt(GIS)and atrazine(ATZ)poses significant risks to aquatic ecosystems.This study investigated the single and joint acute toxicity of a 1:1 GIS-ATZ mixture on zebrafish(Danio rerio).Acute tests determined 96-h LC_(50) values of 123.41 mg/L for GIS and 103.95 mg/L for ATZ.In the joint toxicity test,these values decreased to 60.96 and 50.88 mg/L,respectively.The Additive Index(AI)analysis revealed a consistent synergistic interaction between the herbicides at all exposure intervals.These findings underscore the enhanced ecological threat of herbicide mixtures and highlight the necessity of considering joint effects in environmental risk assessments. 展开更多
关键词 Acute toxicity Joint toxicity Glyphosate isopropyl amine salt ATRAZINE Zebrafish(Danio rerio)
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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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铜钼冶炼污酸中铼萃取的研究进展
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作者 闫虎祥 王庆伟 +3 位作者 蒋国民 桂晓雨 习晨 邹才华 《中南大学学报(自然科学版)》 北大核心 2026年第1期35-46,共12页
铼是航空航天等关键领域不可或缺的稀缺金属,其供需矛盾日益突出。在铜钼冶炼过程中,铼会富集于成分复杂、处理难度大的污酸内,因此从该介质中高效回收铼对保障战略资源供给与实现循环利用具有重要意义。首先,梳理了全球铼资源分布,并... 铼是航空航天等关键领域不可或缺的稀缺金属,其供需矛盾日益突出。在铜钼冶炼过程中,铼会富集于成分复杂、处理难度大的污酸内,因此从该介质中高效回收铼对保障战略资源供给与实现循环利用具有重要意义。首先,梳理了全球铼资源分布,并剖析了铼在冶炼过程中的迁移富集行为与赋存形态;其次,系统评述了目前铼回收的主要方法,包括化学沉淀法、离子交换法、吸附法及溶剂萃取法;最后,总结了常用萃取剂的萃取性能、适用条件与工业应用场景。研究结果表明:全球铼资源90%以上分布于西半球,铜精矿中铼以CuReS_(4)、ReS_(2)形式赋存,冶炼时被氧化为Re_(2)O_(7),经烟气、酸洗进入污酸体系。溶剂萃取法因其对宽浓度范围铼的高适应性、强抗杂质干扰能力以及较好的选择性,成为当前工业应用中的主流技术。然而,复杂体系下萃取剂的长期稳定性欠佳、制备成本偏高,限制了该技术的规模化应用。未来研究需结合分子模拟与高通量筛选技术,加速开发兼具高效性、稳定性与经济性的新型萃取体系,以推动其实际工程应用,最终实现污酸无害化处理与铼资源高效回收的双重目标。 展开更多
关键词 铜钼冶炼 污酸 萃取剂
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Groundwater hydrodynamics and supply sustainability in Punjab,Pakistan:A geological statistical approach using the GAMEAS algorithm based on data from 1105 boreholes
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作者 Muhammad Afzal Tie Liu +6 位作者 An-ming Bao xi chen xiao-hui Pan Solange Uwamahoro Ahmad Mujta Adeel Ahmed Nadeem Asim Qayyum Butt 《China Geology》 2026年第1期44-59,共16页
Effective groundwater management is crucial for economic sustainable development,particularly as climate change and population growth increase the uncertainty of aquifer dynamics.Due to limited geological data,Punjab&... Effective groundwater management is crucial for economic sustainable development,particularly as climate change and population growth increase the uncertainty of aquifer dynamics.Due to limited geological data,Punjab's complex hydrogeological conditions and Quaternary alluvial deposits present significant challenges for groundwater management.This study employs cost-effective numerical techniques as alternatives to traditional methods to safeguard groundwater quality,quantity,and accessibility.It introduces an edit-embedded transition frequency model that integrates regional datasets and utilizes algorithms such as GAMEAS,MCMOD,and TSIM to evaluate aquifer heterogeneity and simulate spatial variations using one-dimensional and three-dimensional Markov chains.Findings show that sand exhibits the highest self-transition(33.112 m),indicating strong stability,followed by silt,clay,and gravel,suggesting overall hydrofacies stability both horizontally and vertically.The model's predictions are largely consistent with actual material distribution,with a slight under-prediction of clay(-0.750%)and an over-prediction of sand(2.985%),which accounts for 58.77%of the aquifer material.It also highlights significant heterogeneity in the northern mountainous regions and minor variations in the south.The study emphasizes Punjab's severe water crisis,with groundwater reserves of 3502.3 BCM,declining water levels(0.38–33.62 m),and low hydraulic conductivity,urging government action on rainwater harvesting and sustainable groundwater management policies. 展开更多
关键词 Groundwater management Economic sustainable development T-progs modelling Aquifer heterogeneity Groundwater sustainability Environment degradation Catchment recharging
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Inhibitory effect of arsenic trioxide on angiogenesis and expression of vascular endothelial growth factor in gastric cancer 被引量:47
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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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An integrate methods to improve the high efficiency of embryo rescue breeding in seedless grapes
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作者 xi chen Khalid Ayesha +8 位作者 Xue Wen Yanan Zhang Mengru Dou Kexuan Jia Yong Wang Yuling Li Feng Sun Guotian Liu Yan Xu 《Journal of Integrative Agriculture》 2026年第2期721-733,共13页
The embryo rescue technique plays an essential role in developing new seedless grape varieties.To enhance the efficiency of seedless grape embryo rescue breeding,this study evaluated 22 hybrid combinations and systema... The embryo rescue technique plays an essential role in developing new seedless grape varieties.To enhance the efficiency of seedless grape embryo rescue breeding,this study evaluated 22 hybrid combinations and systematically investigated the effects of parental genotypes and plant hormones on embryo development and germination.Additionally,an in-depth analysis was conducted on the conversion of abnormal plantlets.Results indicate that‘Ruby Seedless’,‘Delight’,‘Huozhouheiyu’,‘Zitian Seedless’,and‘Zhengyan Seedless’are suitable as maternal parents,whereas‘Zitian Seedless’,‘Shennongxiangfeng’,‘Hongqitezao’,and‘Guibao’perform optimally as paternal parents.Among these,the crosses‘Ruby Seedless×Shennongxiangfeng’and‘Ruby Seedless×Zitian Seedless’exhibited the highest embryo rescue efficiency,with embryo development rates of 55.05 and 59.76%,yielding 1,348 and 2,235 viable plantlets,respectively.When 1.0 mg L^(–1) zeatin (ZT) was added to the MM3 medium supplemented with 0.2 mg L^(–1) indole-3-acetic acid (IAA),the embryo development rate of‘Ruby Seedless×Zitian Seedless’increased by 64.73%.In the WPM germination medium,supplementation with 0.2 mg L^(–1) ZT and 0.2 mg L^(–1) IAA resulted in the highest germination rate of 85.71%for the hybrid combination‘Huozhouheiyu×Shine Muscat’.Furthermore,3,365 abnormal plantlets were rescued via direct transformation and hypocotyl-induced adventitious bud regeneration,among which 1,234 were transformed into normal plantlets.Following hybridization,a total of 4,287 plants were successfully acclimatized and transplanted.This study provides theoretical insights to improve the efficiency of embryo rescue breeding in seedless grapes and offers valuable genetic resources for future breeding programs. 展开更多
关键词 seedless grape embryo rescue parental genotype plant hormones abnormal plantlets
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Numerical Investigation of CO_(2)Contaminant Transport and Deposition in an In-Line Pulse Tube Cryocooler
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作者 Hao Zhu xi chen +3 位作者 Pengcheng Qu Yifan Zhu Haoyi Wang Yingxia Qi 《Frontiers in Heat and Mass Transfer》 2026年第1期54-71,共18页
Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of conta... Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of contaminants,this study develops a two-dimensional axisymmetric model of a linear-type cryocooler to simulate the transport and deposition processes of trace CO_(2),evaluating the impact of contamination on system pressure drop under various operating conditions.Results indicate that CO_(2)diffusion is primarily driven by concentration gradients.The CO_(2)deposition rate increases markedly at low temperatures and high concentrations,with over 90%of deposition occurring in the cold-end heat exchanger.Under different concentration distributions,dry ice predominantly accumulates in the cold-end heat exchanger;however,notable differences emerge in the pulse tube.In the uniform distribution case,CO_(2)tends to deposit along the inner wall of the pulse tube,whereas in the gradual release scenario,deposition mainly occurs on the cold-end flow straightening mesh screen.Dry ice deposition significantly increases the pressure drop across the system and decreases the pressure wave amplitude,resulting in a degradation of cooling capacity.This study lays a foundation for further investigation into the thermal properties of contaminant layers and provides theoretical guidance for optimizing cold-end components to improve contamination resilience. 展开更多
关键词 Pulse tube cryocoolers carbon dioxide dry ice deposition CFD
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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:29
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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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