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Characteristics of transfer zones under the influence of preexisting faults and regional stress transformation:Wenchang A subsag,Zhujiang River Mouth Basin,northern South China Sea
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作者 Wei LI Mingyue CAO +7 位作者 Meifang MENG Caiwei FAN Hui LI Jia LI Wanqiu WU Ruiqing QIN Xingan LI Yiming LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期744-759,共16页
A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon... A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon accumulation conditions,the geometry,kinematics,and reservoir control of a large synthetic overlapping transfer zone in the south of the Wenchang A subsag in the Zhujiang(Pearl)River Mouth basin were investigated.Results indicate that the development and evolution of the transfer zone was controlled by the interaction between pre-existing faults and regional stress transformation.The intense rifting of the main faults of the transfer zone controlled the development of source rocks and faultcontrolled slope break paleogeomorphology.The strike-slip overprint since the Oligocene is conducive to the formation of a large-scale fault-anticline trap,and the secondary faults in the transfer zone contribute to the hydrocarbon transportation.The conjugate intersection area of the NE-and NW-trending faults offers more opportunity for hydrocarbon migration and accumulation. 展开更多
关键词 transfer zone pre-existing fault regional stress transformation CENOZOIC Wenchang A Subsag Zhujiang(Pearl)River Mouth Basin
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Research on the Challenges and Solutions for Ethnic Tourism Service Management in Xichang City,Liangshan Prefecture in the Regional Tourism Era
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作者 Hongyan Duan Yanling Jiang 《Proceedings of Business and Economic Studies》 2024年第4期1-9,共9页
With the advent of the regional tourism era,ethnic tourism service management in Xichang City,Liangshan Prefecture,faces new challenges and opportunities.This paper provides an in-depth analysis of the current state o... With the advent of the regional tourism era,ethnic tourism service management in Xichang City,Liangshan Prefecture,faces new challenges and opportunities.This paper provides an in-depth analysis of the current state of ethnic tourism service management in Xichang City,identifying existing issues such as uneven service quality,an imperfect management system,and the need for improved professional quality among service personnel.To address these problems,the paper proposes several countermeasures,including establishing a service system oriented toward tourists’needs,enhancing professional training for service personnel,and optimizing the management model for tourism service quality.The study aims to promote the sustainable,rapid,and healthy development of tourism in Xichang City,Liangshan Prefecture,and contribute to the prosperity of tourism in Sichuan Province by improving the management level of ethnic tourism services. 展开更多
关键词 regional tourism xichang City Liangshan Prefecture Service management Problems and countermeasures
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选择性凝血因子XI抑制剂在血栓性疾病治疗中的临床研究进展
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作者 张琴 张冬颖 王曦 《四川医学》 CAS 2024年第3期309-314,共6页
血栓性疾病是当今社会的一个重要医疗问题,动脉内血栓形成是引起心肌梗死、缺血性脑卒中、急性肢体缺血的最常见原因,静脉内血栓则可能导致肢体缺血坏死及肺栓塞等严重后果,这些疾病每年共导致全球1000多万人死亡,占所有疾病死亡的50%以... 血栓性疾病是当今社会的一个重要医疗问题,动脉内血栓形成是引起心肌梗死、缺血性脑卒中、急性肢体缺血的最常见原因,静脉内血栓则可能导致肢体缺血坏死及肺栓塞等严重后果,这些疾病每年共导致全球1000多万人死亡,占所有疾病死亡的50%以上,在过去的20年内,这一比例更是增加了25%~35%[1]。目前,抗凝剂是预防和治疗血栓形成的主要手段之一。 展开更多
关键词 凝血因子xi 抗凝药物 反义寡核苷酸 单克隆抗体 小分子抑制剂
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miR-214-5p通过DNMT1介导的AXIN2基因DNA甲基化修饰在皮肤基底细胞癌中的作用机制
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作者 熊斯颖 邵蕾 +2 位作者 杨艳 高爱莉 揭丽云 《新疆医科大学学报》 CAS 2024年第1期27-32,共6页
目的探讨皮肤基底细胞癌中轴抑制蛋白2(Axis inhibition protein 2,AXIN2)基因启动子甲基化对基因转录的影响及miR-214-5p通过靶向DNA甲基转移酶1(DNA methyltransferase1,DNMT1)对AXIN2甲基化率的调控机制。方法收集2022年1月-2023年6... 目的探讨皮肤基底细胞癌中轴抑制蛋白2(Axis inhibition protein 2,AXIN2)基因启动子甲基化对基因转录的影响及miR-214-5p通过靶向DNA甲基转移酶1(DNA methyltransferase1,DNMT1)对AXIN2甲基化率的调控机制。方法收集2022年1月-2023年6月在广州市皮肤病防治所就诊治疗的102例皮肤基底细胞癌(Cutaneous basal cell carcinoma,BCC)患者作为研究对象,提取癌组织和癌旁正常组织标本及基线资料。焦磷酸测序法检测AXIN2基因启动子区甲基化率。实时荧光定量PCR检测AXIN2、DNMT1基因mRNA和miR-214-5p的表达水平。将miR-214-5p模拟物(mimic)、抑制物(inhibitor)及其阴性对照(mimic NC和inhibitor NC)分别对基底细胞癌A431细胞进行转染,48 h后检测DNMT1基因mRNA表达水平和AXIN2基因甲基化率。结果BCC癌组织的AXIN2基因甲基化率显著高于癌旁正常组织(t=5.128,P<0.001),AXIN2基因mRNA相对表达水平显著低于癌旁正常组织(t=7.826,P<0.001),DNMT1基因mRNA表达水平显著高于癌旁正常组织(t=4.838,P<0.001),miR-214-5p表达水平显著低于癌旁正常组织(t=5.426,P<0.001)。BCC癌组织的AXIN2基因甲基化率与其mRNA表达水平呈负相关(r=-0.793,P<0.001),DNMT1基因mRNA水平与AXIN2基因甲基化率呈正相关(r=0.814,P<0.001),miR-214-5p表达水平与DNMT1基因mRNA水平呈负相关(r=-0.747,P<0.001)。双荧光素酶报告基因实验结果证实,DNMT1是miR-214-5p的靶基因。细胞转染后,与mimic NC、inhibitor和inhibitor NC比较,mimic的DNMT1基因mRNA水平、AXIN2基因甲基化率显著降低(P<0.001);而inhibitor的DNMT1基因mRNA水平和AXIN2基因甲基化率相较于其他三组明显上升(P<0.001)。结论miR-214-5p可通过调控下游靶蛋白DNMT1表达,影响AXIN2基因的DNA甲基化率,调控AXIN2基因的表达水平,参与皮肤基底细胞癌的发生机制。 展开更多
关键词 基底细胞癌 miR-214-5p DNA甲基化转移酶1 轴抑制蛋白2 启动子区甲基化
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Helicobacter pylori infection in Xinjiang Uyghur Autonomous Region:Prevalence and analysis of related factors 被引量:1
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作者 Yu-Hua Peng Xue Feng +2 位作者 Zhong Zhou Lei Yang Yun-Fei Shi 《World Journal of Gastroenterology》 SCIE CAS 2023年第43期5834-5847,共14页
BACKGROUND^(14)C urea breath test(^(14)C UBT)and immunohistochemical staining(IHC)are widely used for detection Helicobacter pylori(H.pylori)infection with different sensitivity,and there is a difference in H.pylori i... BACKGROUND^(14)C urea breath test(^(14)C UBT)and immunohistochemical staining(IHC)are widely used for detection Helicobacter pylori(H.pylori)infection with different sensitivity,and there is a difference in H.pylori infection rate in Uyghur and Han ethnic groups.Both need large cohort studies to evaluate the differences more accurately.AIM To analyze the difference between^(14)C UBT and IHC for H.pylori detection in Xinjiang Uyghur Autonomous Region and the difference between Uyghur and Han populations.METHODS There were 3944 cases of H.pylori infection detected by both IHC and^(14)C UBT at the same time(interval<1 wk,with sampling site including gastric antrum,selected from 5747 patients).We compared the sensitivity of^(14)C UBT and IHC.We also compared 555 pairs of Han/Uyghur cases(completely matched for gender and age)for their H.pylori infection rates.The overall H.pylori infection rate of all 5747 cases and the correlation with other clinicopathological data were also further analyzed.SPSS V23.0 software was used for statistical analysis.RESULTS The sensitivity was 94.9%for^(14)C UBT and 65.1%for IHC,which was a significant difference(n=3944,P<0.001).However,among those cases negative for H.pylori by^(14)C UBT(detection value≤100),4.8%were positive by IHC.Combining both methods,the overall H.pylori infection rate was 48.6%(n=5747),and differences in gender,age group,ethnicity and region of residence significantly affected the H.pylori positive rates.According to age group(Han/Uyghur),the positive rates were≤30 years(62.2%/100.0%),31-40 years(45.2%/85.7%),41-50 years(47.2%/79.2%),51-60 years(44.6%/76.1%),61-70 years(40.9%/68.2%),71-80 years(41.7%/54.1%)and≥81 years(42.9%/NA).The H.pylori infection rates of Han/Uyghur paired cases were 41.4%and 73.3%,which was a significant difference(P<0.001)(555 pairs).H.pylori positivity was significantly related to moderate-severe grade 2-3 chronic/active gastritis and intestinal metaplasia(all P<0.05).CONCLUSION The sensitivity of^(14)C UBT was significantly higher,but combined application can still increase the accuracy.The prevention H.pylori should be emphasized for Uygur and young people. 展开更多
关键词 Helicobacter pylori IMMUNOHISTOCHEMISTRY 14C urea breath test HAN UYGHUR xinjiang Uyghur Autonomous region
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Does digitalization mitigate regional inequalities?Evidence from China 被引量:1
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作者 Haimeng Liu Xinyang Wang +1 位作者 Zheye Wang Yu Cheng 《Geography and Sustainability》 CSCD 2024年第1期52-63,共12页
Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into t... Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into the interplay between them.By analyzing the economic development and digitalization gaps at regional and city levels in China,extending the original Cobb-Douglas production function,this study aims to evaluate the impact of digitalization on China's regional inequality using seemingly unrelated regression.The results indicate a greater emphasis on digital inequality compared to economic disparity,with variable coefficients of 0.59 for GDP per capita and 0.92 for the digitalization index over the past four years.However,GDP per capita demonstrates higher spatial concentration than digitalization.Notably,both disparities have shown a gradual reduction in recent years.The southeastern region of the Hu Huanyong Line exhibits superior levels and rates of economic and digital advancement in contrast to the northwestern region.While digitalization propels economic growth,it yields a nuanced impact on achieving balanced regional development,encompassing both positive and negative facets.Our study highlights that the marginal utility of advancing digitalization is more pronounced in less developed regions,but only if the government invests in the digital infrastructure and education in these areas.This study's methodology can be utilized for subsequent research,and our findings hold the potential to the government's regional investment and policy-making. 展开更多
关键词 regional inequality regional disparities Digital divide DIGITALIZATION Sustainable development Economic growth Seemingly unrelated regression
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A core-satellite self-assembled SERS aptasensor containing a“biological-silent region”Raman tag for the accurate and ultrasensitive detection of histamine 被引量:1
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作者 Chen Chen Yingfang Zhang +3 位作者 Ximo Wang Xuguang Qiao Geoffrey I.N.Waterhouse Zhixiang Xu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1029-1039,共11页
Herein,a novel interference-free surface-enhanced Raman spectroscopy(SERS)strategy based on magnetic nanoparticles(MNPs)and aptamer-driven assemblies was proposed for the ultrasensitive detection of histamine.A core-s... Herein,a novel interference-free surface-enhanced Raman spectroscopy(SERS)strategy based on magnetic nanoparticles(MNPs)and aptamer-driven assemblies was proposed for the ultrasensitive detection of histamine.A core-satellite SERS aptasensor was constructed by combining aptamer-decorated Fe_(3)O_(4)@Au MNPs(as the recognize probe for histamine)and complementary DNA-modified silver nanoparticles carrying 4-mercaptobenzonitrile(4-MBN)(Ag@4-MBN@Ag-c-DNA)as the SERS signal probe for the indirect detection of histamine.Under an applied magnetic field in the absence of histamine,the assembly gave an intense Raman signal at“Raman biological-silent”region due to 4-MBN.In the presence of histamine,the Ag@4-MBN@Ag-c-DNA SERS-tag was released from the Fe_(3)O_(4)@Au MNPs,thus decreasing the SERS signal.Under optimal conditions,an ultra-low limit of detection of 0.65×10^(-3)ng/mL and a linear range 10^(-2)-10^5 ng/mL on the SERS aptasensor were obtained.The histamine content in four food samples were analyzed using the SERS aptasensor,with the results consistent with those determined by high performance liquid chromatography.The present work highlights the merits of indirect strategies for the ultrasensitive and highly selective SERS detection of small biological molecules in complex matrices. 展开更多
关键词 Surface-enhanced Raman spectroscopy Raman biological-silent region APTAMER Histamine detection Universal SERS-tag
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Construction and Application of a Regional Kilometer-Scale Carbon Source and Sink Assimilation Inversion System(CCMVS-R) 被引量:1
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作者 Lifeng Guo Xiaoye Zhang +8 位作者 Junting Zhong Deying Wang Changhong Miao Licheng Zhao Zijiang Zhou Jie Liao Bo Hu Lingyun Zhu Yan Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期263-275,共13页
CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate ... CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate warming since the 1950s and leading to an increased frequency of extreme weather and climate events.In 2020,China committed to striving for carbon neutrality by 2060.This commitment and China’s consequent actions will result in significant changes in global and regional anthropogenic carbon emissions and therefore require timely,comprehensive,and objective monitoring and verification support(MVS)systems.The MVS approach relies on the top-down assimilation and inversion of atmospheric CO_(2)concentrations,as recommended by the Intergovernmental Panel on Climate Change(IPCC)Inventory Guidelines in 2019.However,the regional high-resolution assimilation and inversion method is still in its initial stage of development.Here,we have constructed an inverse system for carbon sources and sinks at the kilometer level by coupling proper orthogonal decomposition(POD)with four-dimensional variational(4DVar)data assimilation based on the weather research and forecasting-greenhouse gas(WRF-GHG)model.Our China Carbon Monito ring and Verification Support at the Regional level(CCMVS-R)system can continuously assimilate information on atmospheric CO_(2)and other related information and realize the inversion of regional and local anthropogenic carbon emissions and natural terrestrial ecosystem carbon exchange.Atmospheric CO_(2)data were collected from six ground-based monito ring sites in Shanxi Province,China to verify the inversion effect of regio nal anthropogenic carbon emissions by setting ideal and real experiments using a two-layer nesting method(at 27 and 9 km).The uncertainty of the simulated atmospheric CO_(2)decreased significantly,with a root-mean-square error of CO_(2)concentration values between the ideal value and the simulated after assimilation was close to 0.The total anthropogenic carbon emissions in Shanxi Province in 2019 from the assimilated inversions were approximately 28.6%(17%-38%)higher than the mean of five emission inventories using the bottomup method,showing that the top-down CCMVS-R system can obtain more comprehensive information on anthropogenic carbon emissions. 展开更多
关键词 CCMVS-R regional carbon assimilation system Anthropogenic carbon emissions CO_(2) POD 4DVar
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Electroacupuncture alleviates orofacial allodynia and anxiety-like behaviors by regulating synaptic plasticity of the CA1 hippocampal region in a mouse model of trigeminal neuralgia
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作者 JIA Yuzhi LI Haitao +9 位作者 ZHANG Guangming WU Hongyun ZHANG Sishuo ZHI Hongwei WANG Yahan ZHU Jingwen WANG Yifan XU Xiangqing TIAN Caijun CUI Wenqiang 《中国药理学与毒理学杂志》 CAS 北大核心 2023年第S01期69-70,共2页
OBJECTIVE To investigate whether electroacupuncture(EA)ameliorates abnormal trigeminal neuralgia(TN)orofacial pain and anxiety-like behavior by altering synaptic plasticity in the hippocampus CA1.METHODS A mouse infra... OBJECTIVE To investigate whether electroacupuncture(EA)ameliorates abnormal trigeminal neuralgia(TN)orofacial pain and anxiety-like behavior by altering synaptic plasticity in the hippocampus CA1.METHODS A mouse infraorbital nerve transection model(pTION)of neuropathic pain was established,and EA or sham EA was used to treat ipsilateral acu⁃puncture points(GV20-Baihui and ST7-Xia⁃guan).Golgi-Cox staining and transmission elec⁃tron microscopy(TEM)were administrated to observe the changes of synaptic plasticity in the hippocampus CA1.RESULTS Stable and persistent orofacial allodynia and anxiety-like behav⁃iors induced by pT-ION were related to changes in hippocampal synaptic plasticity.Golgi stain⁃ings showed a decrease in the density of dendritic spines,especially mushroom-type dendritic spines,in hippocampal CA1 neurons of pT-ION mice.TEM results showed that the density of synapses,membrane thickness of the postsynaptic density,and length of the synaptic active zone were decreased,whereas the width of the synaptic cleft was increased in pTION mice.EA attenu⁃ated pT-ION-induced orofacial allodynia and anx⁃iety-like behaviors and effectively reversed the abnormal changes in dendritic spines and syn⁃apse of the hippocampal CA1 region.CONCLU⁃SION EA modulates synaptic plasticity of hippo⁃campal CA1 neurons,and reduces abnormal oro⁃facial pain and anxiety-like behavior,providing evidence for a TN treatment strategy. 展开更多
关键词 trigeminaing neuralgia anxiety ELECTROACUPUNCTURE synaptic plasticity hippocampal CA1 region
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Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region 被引量:1
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作者 ZHANG Shuqin LIAO Qinghua +4 位作者 LIU Chunlei GAO Xiaoyu LONG Jingchao LI Pengyuan XU Jianjun 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期605-617,共13页
Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-Apr... Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification. 展开更多
关键词 explosive cyclone diabatic heating cyclonic-vorticity advection rapid intensification the Kuroshio/Kuroshio Extension region
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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet 被引量:1
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作者 Yumeng Liu Xianhong Meng +5 位作者 Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期47-53,共7页
Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i... Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ. 展开更多
关键词 Summer precipitation East Asian subtropical westerly jet Three River Source region Atlantic-Eurasian teleconnection
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Retrieval and Regional Distribution Analysis of Ammonia,Sulfur Dioxide and Nitrogen Dioxide in the Urban Environment Using Ultraviolet DOAS Algorithm
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作者 Hao Chen Jie Xu +5 位作者 YiboHu Fuzhou Niu Zhiyan Li Dan Wang Guizhong Fu Chuanxin Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1251-1262,共12页
Aiming at the in situ and mobile observation of urban environmental air pollution,a portable instrument using ultraviolet spectrum retrieval algorithm was developed based on the basis of Differential Optical Absorptio... Aiming at the in situ and mobile observation of urban environmental air pollution,a portable instrument using ultraviolet spectrum retrieval algorithm was developed based on the basis of Differential Optical Absorption Spectroscopy(DOAS)and multiple-pass cell technique.Typical trace gas pollutants,NH3,SO2,and NO2,were explored using their optical spectral characteristics in deep ultraviolet wavelength range from 210 to 215 nm.The gas concentration was retrieved by Lambert-Beer’s law and nonlinear least square method.With an optimized optical alignment,the detection limits of NH3,SO2,NO2 were estimated to be 2.2,2.3,and 36.2 ppb,respectively.The system was used in carrying out some cruise observations in Chengdu,China.During the entire period,the polluted gases showed varied distribution and typical daily average concentrations ofNH3,SO2,NO2 were 23.2,3.5,and 106.0 ppb,respectively.The contributions from different sources were analyzed combined with the HYSPLIT model.Results show that the portable DOAS system is a convenient and effective tool for regional distribution measurement and pollution source monitoring. 展开更多
关键词 Ultraviolet DOAS algorithm retrieve method white cell urban environment regional distribution
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Characteristics and driving factors of abandoned cultivated land in the hilly regions of southern China:A case study in Longnan,Jiangxi Province
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作者 CHEN Ze-bin CHEN Yong-lin +4 位作者 LI Chao-jun LIN Jian-ping CHEN Pei-ru SUN Wei-wei WAN Zhi-wei 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1483-1498,共16页
The abandonment of cultivated land in southern China was gradually obvious.This research aims to provide a reference for solving the abandonment of cultivated land in hilly regions and promote rural development in Chi... The abandonment of cultivated land in southern China was gradually obvious.This research aims to provide a reference for solving the abandonment of cultivated land in hilly regions and promote rural development in China.We examined Longnan county located in the hilly regions of southern China as an example,where abandoned cultivated land is very common.We analyzed its land use data with a field survey to identify the abandoned cultivated land and geospatial characteristics.From the two aspects of social and natural factors,we analyzed the factors driving cultivated land abandonment with the help of Geodetector.The results showed that in 2019,the total area of the abandoned cultivated land in Longnan county was 4,962.35 hm^(2),covering 39.51% of this region.Among the topographic factors,the abandonment rate is positively correlated with elevation and slope gradient,but not with slope direction.Among the land parcel conditions,the abandonment rate is positively correlated with the access to road network and cultivation distance from settlement.At the county level,the abandonment of cultivated land in study area was affected by multiple factors,among which,the direct factor was the reduction in the labor force,such as the decrease of farming laborers and the increase of female population,which made farming unsustainable.Changes in production factors also promoted transformations in farmers’motivation to engage in production,such as the decrease of grain crops and the increase of cash crops,which was the indirect factor affecting cultivated land abandonment.The development of the rural nonagricultural industry affected farmers’enthusiasm,such as the decrease of farming households,which was the fundamental factor leading to cultivated land abandonment in this area. 展开更多
关键词 Cultivated land abandonment Spatial distribution Geodetector Driving factor Hilly region County level
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Xi’s America Trip Injects Positive Energy into the International and Regional Landscape
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《China Today》 2023年第12期6-15,共10页
President Xi Jinping’s America trip from November 14 to 17,including his talks with U.S.President Joe Biden and his attendance at the 30th APEC Economic Leaders’Meeting in San Francisco,is widely believed to have ad... President Xi Jinping’s America trip from November 14 to 17,including his talks with U.S.President Joe Biden and his attendance at the 30th APEC Economic Leaders’Meeting in San Francisco,is widely believed to have added stability to China-U.S.relations,brought new impetus to Asia-Pacific cooperation and injected positive energy into the international and regional landscape. 展开更多
关键词 COOPERATION AMERICA regionAL
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Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt
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作者 Asmaa S ABO HATAB Yassin M AL-SODANY +2 位作者 Kamal H SHALTOUT Soliman A HAROUN Mohamed M EL-KHALAFY 《Journal of Arid Land》 SCIE CSCD 2024年第7期1000-1021,I0002-I0044,共65页
Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emira... Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic species in Egypt, i.e., Ⅰ Asphodelus refractus group, Ⅱ Agathophora alopecuroides var. papillosa group, Ⅲ Anvillea garcinii group, Ⅳ Reseda muricata group, V Agathophora alopecuroides var. alopecuroides group, Ⅵ Scrophularia deserti group, and Ⅶ Astragalus schimperi group. It's crucial to clearly define the Saharo-Arabian endemics and illustrate an updated verified database of these taxa for a given territory for providing future management plans that support the conservation and sustainable use of these valuable species under current thought-provoking devastating impacts of rapid anthropogenic and climate change in this region. 展开更多
关键词 ENDEMISM phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)
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Investigation of Groundwater Quality with Borehole Depth in the Basin Granitoids of the Ashanti Region of Ghana
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作者 Bernard Ofosu Augustine Kofi Asante +2 位作者 Festus Anane Mensah Umar-Farouk Usman Naa Korkoi Ayeh 《Journal of Water Resource and Protection》 CAS 2024年第5期381-394,共14页
The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study ther... The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study therefore seeks to investigate the relationship between borehole depth and groundwater quality across the granitoid aquifers within the Birimian Supergroup in the Ashanti Region. Physicochemical analysis records of groundwater quality data were collected from 23 boreholes of public and private institutions in the Ashanti Region of Ghana, and the parametric values of iron, fluoride, total hardness, pH, nitrate, and nitrite were used to study the groundwater quality-depth relationship. The results showed that the depth-to-groundwater quality indicated a marginal increase in water quality in the range of 30 to 50 m, which is mathematically represented by the low-value correlation coefficient (r<sup>2</sup> = 0.026). A relatively significant increase occurs in the depth range of 50 to 80 m, which is given by a correlation coefficient of r<sup>2</sup> = 0.298. The mean percent parameter compatibility was 74%, 82%, 89%, and 97% at 50, 60, 70, and 80 m depths, respectively. The variations in groundwater quality per depth ratio ranged from 1.48, 1.37, 1.27, and 1.21 for 50, 60, 70, and 80 m depth, respectively. The recommended minimum borehole depth for excellent groundwater quality is suggested with a compatibility per meter depth ratio of 1.37. This results in a range between 50 and 70 m as the most desirable drilling depth for excellent groundwater quality within the granitoids of the Birimian Supergroup of the Ashanti Region in Ghana. 展开更多
关键词 Groundwater Quality Borehole Depth Birimian Supergroup Granitoid Aquifers Ashanti region
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Effects of cementation on physical properties of clastic rock-originated weathering crust reservoirs in the Kexia region,Junggar Basin,NW China
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作者 Changhai Gao Shida Meng +2 位作者 Jiahao Zhang Jian Wang Yifei Sun 《Energy Geoscience》 2023年第1期74-82,共9页
Cements are widely developed in clastic rock-originated weathering crust(CWC)reservoirs in the Kexia region along the northwestern margin of the Junggar Basin and significantly affect reservoir physical properties and... Cements are widely developed in clastic rock-originated weathering crust(CWC)reservoirs in the Kexia region along the northwestern margin of the Junggar Basin and significantly affect reservoir physical properties and oil and gas distribution in this area.Focusing on the CWC reservoirs at the top of both the Permian Jiamuhe Formation and the Triassic Karamay Formation,this study analyzed the types and characteristics of cements in the reservoirs and explored their effects on reservoir physical properties based on thin sections,SEM images,XRD results,and tests of physical properties.The main results are as follows.The cements in the CWC reservoirs in Kexia region mainly consist of carbonate minerals(41.5%),clay minerals(27.8%)and zeolite minerals(30%),as well as small amount of siliceous minerals.Among them,the carbonate minerals are dominated by siderite and calcite,the clay minerals mainly include kaolinite,interstratified illite/smectite(I/S)and chlorite,and the zeolite minerals primarily comprise heulandite and laumontite.These different types of multiphase cements are generally paragenetic or associated and affect reservoir physical properties to different degrees.Specifically,the carbonate and clay cements of the early diagenetic stage reduced the reservoirs’average porosity from 21%to 15%.The dissolution of some carbonate and zeolite cements in the early A substage of the middle diagenetic stage restored the average porosity to 18%,and the cementation in the late A substage decreased the average porosity to 13%again,of which about 4%was reduced by carbonate cements.The average porosity of the CWC reservoirs gradually decreased to the current value of approximately 10%in the B substage of the middle diagenetic stage.The impact of cementation on the CWC reservoirs can reach as far as 70 m below the unconformity.Moreover,the types and contents of cements vary with their depth below the unconformity surface,leading to the development of multiple zones with high cement content and the differentiated oil and gas distribution. 展开更多
关键词 Clastic rock-originated weathering crust Cementation characteristic Physical properties Pore evolution Kexia region Junggar Basin
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Prevalence of Enteric Pathogens Associated with Infections among Table Egg Consumers in Some Primary Health Establishments in the Center Region of Cameroon
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作者 Mariane Lucie Ngueguim Bernard Viban Tangwa +2 位作者 Victor Ngu Ngwa Albert Ngakou Abdoulmoumini Mamoudou 《Advances in Infectious Diseases》 CAS 2024年第3期606-619,共14页
Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains o... Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains of stomach disorders after egg consumption. Data related to sociodemographic characteristics and other factors were collected using a structured based questionnaire. Stool culture of utmost importance in stomach disorders patients and serum were collected for typhoid serological test. Results: A total of 207 participants took part in the survey, Results indicated nontyphoidal Salmonella infections were highest in the 3 areas of study with Mfoundi (73.44%) having the highest level of infection compared to other bacterial infection. other enteric bacteria associated to this infection were E. coli serotype 157, Aeromonas, Citrobacter freundii, Enterobacter cloaca and typhi salmonella. Meanwhile salmonelosis caused by typhic salmonella had highest prevalence in the Lekie Division (13.11%) as a result of poor hygienic practices associated with the conservation and preparation of eggs, Stool culture was observed to detect more positive cases in the diagnosis of typhoid fever than Widal test, but with no statistically significant (p > 0.05) difference between the stool culture and Widal test in the 3 areas of study. Conclusion: this study revealed that egg consumers are pruned to enteric bacterial and salmonella infections depending on how and where egg is consumed. 展开更多
关键词 Enteric Pathogens Table Eggs Consumption Center region Cameroon
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Dust-Holding Capacity and Bio-Chemical Changes of Plant Species Growing in an Around Opencast Mining Area of Bundelkhand Region of Uttar Pradesh, India
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作者 Priyanka Singh Amit Pal 《American Journal of Plant Sciences》 CAS 2024年第8期677-698,共22页
The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bu... The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bundelkhand University campus treated as control site. Plant species existing under a polluted environment for a long time may be considered as potentially resistant species and recommended for green belt design in mining areas, especially to cope with dust pollution. Results showed the pollution level, especially of mining-originated dust particles holding capacity of leaves and effects of different biochemical parameters (Total Chlorophyll, Protein and Carotenoid) of existing plant species both from mining areas as well as from Bundelkhand University campus. Based on their performances, Tectona grandis L., Ficus hispida L., Calotropis procera Aiton., Butea monosperma Lam. and Ficus benghalensis L., etc. are highly tolerant species while Ficus infectoria L., Artocarpus heterophyllus Lam., Ipomoea purpurea L., Allianthus excelsa Roxb. and Bauhinia variegata L. are intermediate tolerant species. T. grandis had shown the highest dust-holding capacity (2.566 ± 0.0004 mg/cm2) whereas Albizia procera (0.018 ± 0.0002 mg/cm2) was found to be the lowest dust-holding capacity. Our findings also showed that the T. grandis and F. hispida have significant dust deposition with minimal effect of dust on their leaf chlorophyll (17.447 ± 0.019 mg/g and 14.703 ± 0.201 mg/g), protein (0.699 ± 0.001 mg/g and 0.604 ± 0.002 mg/g) and carotenoid (0.372 ± 0.003 mg/g and 0.354 ± 0.003 mg/g) content respectively among all selected plant species. Therefore, in the present investigation, plant species with high tolerance to high dust-holding capacity on their leaf surfaces are preferable for green corridors as open cast granite mines and their adjacent areas. 展开更多
关键词 Bundelkhand region Biochemical Changes Dust-Holding Capacity Chlorophyll Content Open Cast Granite Mining
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终末期肝病模型-XI评分对急性心肌梗死冠状动脉支架植入术后患者预后的预测价值
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作者 公方娜 单鸿伟 +3 位作者 廉明 宝璐尔 阿拉腾宝力德 关宏 《中国循证心血管医学杂志》 2024年第8期983-985,共3页
目的 探讨终末期肝病模型-XI(MELD-XI)评分对急性心肌梗死患者冠状动脉支架植入术后的预后的预测价值。方法 回顾性收集2021年1月至2022年12月于内蒙古医科大学附属医院收治的急性心肌梗死患者226例,根据入院时MELD-XI评分,将患者分为高... 目的 探讨终末期肝病模型-XI(MELD-XI)评分对急性心肌梗死患者冠状动脉支架植入术后的预后的预测价值。方法 回顾性收集2021年1月至2022年12月于内蒙古医科大学附属医院收治的急性心肌梗死患者226例,根据入院时MELD-XI评分,将患者分为高MELD-XI评分组和低MELD-XI评分组,每组各113例。比较两组患者近、远期预后。结果 与低MELD-XI评分组比较,高MELD-XI评分组患者左室射血分数(LVEF)显著降低[(51.67±7.91)%vs.(60.91±5.91)%],(P<0.001);N末端脑钠肽前体(NT-proBNP)显著增高(822.87±462.38) vs.(701.84±338.21)ng/L,(P=0.026)。与低MELD-XI评分组比较,高MELD-XI评分组患者不良结局事件的发生率显著增高(16.81%vs. 6.19%,P=0.012)。MELD-XI评分对急性心肌梗死冠状动脉支架植入术后不良结局事件具有一定的预测价值,曲线下面积为0.732,95%CI:0.671~0.798,(P<0.001)。结论 MELD-XI对于预测急性心肌梗死患者预后具有一定的参考价值。 展开更多
关键词 终末期肝病模型-xi 急性心肌梗死 心脏功能 预后 冠状动脉支架植入术
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