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Special Issue:Questions&Data for Better Science and Innovation Call for submissions
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《Journal of Data and Information Science》 CSCD 2024年第3期I0002-I0002,共1页
Editors Yang Wang,Xi'an Jiaotong University Dongbo Shi,Shanghai Jiaotong University Ye Sun,University College London Zhesi Shen,National Science Library,CAS Topic of the Special Issue What are the top questions to... Editors Yang Wang,Xi'an Jiaotong University Dongbo Shi,Shanghai Jiaotong University Ye Sun,University College London Zhesi Shen,National Science Library,CAS Topic of the Special Issue What are the top questions towards better science and innovation and the required data to answer these questions? 展开更多
关键词 COLLEGE QUESTIONS issue
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Enhancing Multicriteria-Based Recommendations by Alleviating Scalability and Sparsity Issues Using Collaborative Denoising Autoencoder
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作者 S.Abinaya K.Uttej Kumar 《Computers, Materials & Continua》 SCIE EI 2024年第2期2269-2286,共18页
A Recommender System(RS)is a crucial part of several firms,particularly those involved in e-commerce.In conventional RS,a user may only offer a single rating for an item-that is insufficient to perceive consumer prefe... A Recommender System(RS)is a crucial part of several firms,particularly those involved in e-commerce.In conventional RS,a user may only offer a single rating for an item-that is insufficient to perceive consumer preferences.Nowadays,businesses in industries like e-learning and tourism enable customers to rate a product using a variety of factors to comprehend customers’preferences.On the other hand,the collaborative filtering(CF)algorithm utilizing AutoEncoder(AE)is seen to be effective in identifying user-interested items.However,the cost of these computations increases nonlinearly as the number of items and users increases.To triumph over the issues,a novel expanded stacked autoencoder(ESAE)with Kernel Fuzzy C-Means Clustering(KFCM)technique is proposed with two phases.In the first phase of offline,the sparse multicriteria rating matrix is smoothened to a complete matrix by predicting the users’intact rating by the ESAE approach and users are clustered using the KFCM approach.In the next phase of online,the top-N recommendation prediction is made by the ESAE approach involving only the most similar user from multiple clusters.Hence the ESAE_KFCM model upgrades the prediction accuracy of 98.2%in Top-N recommendation with a minimized recommendation generation time.An experimental check on the Yahoo!Movies(YM)movie dataset and TripAdvisor(TA)travel dataset confirmed that the ESAE_KFCM model constantly outperforms conventional RS algorithms on a variety of assessment measures. 展开更多
关键词 Recommender systems multicriteria rating collaborative filtering sparsity issue scalability issue stacked-autoencoder Kernel Fuzzy C-Means Clustering
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Leveraging User-Generated Comments and Fused BiLSTM Models to Detect and Predict Issues with Mobile Apps
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作者 Wael M.S.Yafooz Abdullah Alsaeedi 《Computers, Materials & Continua》 SCIE EI 2024年第4期735-759,共25页
In the last decade, technical advancements and faster Internet speeds have also led to an increasing number ofmobile devices and users. Thus, all contributors to society, whether young or old members, can use these mo... In the last decade, technical advancements and faster Internet speeds have also led to an increasing number ofmobile devices and users. Thus, all contributors to society, whether young or old members, can use these mobileapps. The use of these apps eases our daily lives, and all customers who need any type of service can accessit easily, comfortably, and efficiently through mobile apps. Particularly, Saudi Arabia greatly depends on digitalservices to assist people and visitors. Such mobile devices are used in organizing daily work schedules and services,particularly during two large occasions, Umrah and Hajj. However, pilgrims encounter mobile app issues such asslowness, conflict, unreliability, or user-unfriendliness. Pilgrims comment on these issues on mobile app platformsthrough reviews of their experiences with these digital services. Scholars have made several attempts to solve suchmobile issues by reporting bugs or non-functional requirements by utilizing user comments.However, solving suchissues is a great challenge, and the issues still exist. Therefore, this study aims to propose a hybrid deep learningmodel to classify and predict mobile app software issues encountered by millions of pilgrims during the Hajj andUmrah periods from the user perspective. Firstly, a dataset was constructed using user-generated comments fromrelevant mobile apps using natural language processing methods, including information extraction, the annotationprocess, and pre-processing steps, considering a multi-class classification problem. Then, several experimentswere conducted using common machine learning classifiers, Artificial Neural Networks (ANN), Long Short-TermMemory (LSTM), and Convolutional Neural Network Long Short-Term Memory (CNN-LSTM) architectures, toexamine the performance of the proposed model. Results show 96% in F1-score and accuracy, and the proposedmodel outperformed the mentioned models. 展开更多
关键词 Mobile apps issues play store user comments deep learning LSTM bidirectional LSTM
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Comparative Study on the Policy of Multiplicity Issues in Clinical Trials at Home and Abroad
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作者 Gong Jingran Chang Yingnan +1 位作者 Qiao Jiahui Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第1期43-49,共7页
Objective To study the content of China’s guiding principles on multiplicity issues in clinical trials,and to provide reference for the revision of China’s relevant guiding principles.Methods Based on ICH E9,the sim... Objective To study the content of China’s guiding principles on multiplicity issues in clinical trials,and to provide reference for the revision of China’s relevant guiding principles.Methods Based on ICH E9,the similarities and differences of the guiding principles of US Food and Drug Administration(FDA),European Medicines Agency(EMA),and National Medical Products Administration(NMPA)on the multiplicity issues in clinical trials were compared one by one.Results and Conclusion In general,NMPA guidelines are based on ICH E9,but in detail,the guidelines of FDA and EMA focus differently on the multiplicity issues.Therefore,NMPA guidelines need to be detailed and comprehensive.NMPA guidelines can be refined by referring to foreign guidelines to improve the practical guiding significance for clinical research and promote the level of domestic clinical trials in line with international standards. 展开更多
关键词 clinical trial multiplicity issue solution strategy
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Anode Interfacial Issues in Solid-State Li Batteries:Mechanistic Understanding and Mitigating Strategies 被引量:1
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作者 Jiacheng Wang Liquan Chen +1 位作者 Hong Li Fan Wu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期384-404,共21页
All-solid-state Li metal batteries(ASSLBs)using inorganic solid electrolyte(SE)are considered promising alternatives to conventional Li-ion batteries,offering improved safety and boosted energy density.While significa... All-solid-state Li metal batteries(ASSLBs)using inorganic solid electrolyte(SE)are considered promising alternatives to conventional Li-ion batteries,offering improved safety and boosted energy density.While significant progress has been made on improving the ionic conductivity of SEs,the degradation and instability of Li metal/inorganic SE interfaces have become the critical challenges that limit the coulombic efficiency,power performance,and cycling stability of ASSLBs.Understanding the mechanisms of complex/dynamic interfacial phenomena is of great importance in addressing these issues.Herein,recent studies on identifying,understanding,and solving interfacial issues on anode side in ASSLBs are comprehensively reviewed.Typical issues at Li metal/SE interface include Li dendrite growth/propagation,SE cracking,physical contact loss,and electrochemical reactions,which lead to high interfacial resistance and cell failure.The causes of these issues relating to the chemical,physical,and mechanical properties of Li metal and SEs are systematically discussed.Furthermore,effective mitigating strategies are summarized and their effects on suppressing interfacial reactions,improving interfacial Li-ion transport,maintaining interfacial contact,and stabilizing Li plating/stripping are highlighted.The in-depth mechanistic understanding of interfacial issues and complete investigations on current solutions provide foundations and guidance for future research and development to realize practical application of high-performance ASSLB. 展开更多
关键词 all-solid-state Li metal batteries anode interfacial issues interface protection and modification interfacial reaction and evolution li dendrite growth
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Environmental Issues of Geothermal Development in Yangbajing, Tibet and the Countermeasures 被引量:4
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作者 LiHui-xia HeXiao-rong +1 位作者 HuXian-cai DuoJi 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期965-974,共10页
The pollution source and pollution state of surface water is respectively assessed with equal-standard-pollution-load index and Nemero index, and the habitans' health is assessed as well by comparison with pre-dev... The pollution source and pollution state of surface water is respectively assessed with equal-standard-pollution-load index and Nemero index, and the habitans' health is assessed as well by comparison with pre-development of geo-thermal field. Results show that: 1) Three pollutive factors obviously fail to attain the required standards and their order sorted by impact degree is As>F- >S2-. 2) The Nemero index of Donggua cross section of Duilongqu River is 0. 725 and the water quality is at mildly-polluted level. 3) In Lhasa River, the Nemero indexes of cross sections affected by geo-thermal fields are much higher than that of the unaffected one, which shows the present and potential impacts of geo-thermal development. 4) Much more inhabitants nearby got trichomadesis sickness after geothermal development, which shows that the surface water pollution in this area has threatened the inhabitants' health. In addition, other environmental issues caused by Yangbajing geothermal development are analyzed and some countermeasures are proposed. 展开更多
关键词 Yangbajing of tibet geothermal energy resources equal-standard-pollution-load index Nemero index counter measures
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Geochronology and Geochemistry of Ore-related Granitoids in the Giant Gariatong Rb Deposit,Tibet and Implications for Rb Metallogeny in China 被引量:1
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作者 LIN Bin TANG Juxing +8 位作者 TANG Pan SUN Yan QI Jing MSANTOSH XIE Jinling DENG Shilin LI Faqiao XIE Fuwei ZHOU Aorigele 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期83-103,共21页
Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at ... Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at Gariatong in the Central Lhasa terrane in Tibet.Detailed field studies and logging data revealed that the Rb mineralization mainly occurs in monzogranite and is related to greisenization.LA-ICP-MS U-Pb dating of zircon yielded ages of 19.1±0.2 Ma and 19.0±0.2 Ma for greisenized monzogranite and fresh monzogranite,respectively.The monzogranites are characterized as strongly peraluminous,with high contents of SiO2,Al2O3,K2O and Na2O as well as a high differentiation index.They are enriched in light rare earth and large ion lithophile elements with significant negative Eu anomalies and depleted high fieldstrength elements.Petrological and geochemical features of these ore-related monzogranites suggest that they are highly fractionated S-type granites,derived from remelting of crustal materials in a post-collisional setting.The geochemistry of zircon and apatite points to a low oxygen fugacity of the ore-related monzogranite during the magma’s evolution.The discovery of the Gariatong Rb deposit suggests that the Central Lhasa terrane may be an important region for rare metal mineralization. 展开更多
关键词 LA-ICP-MS U-Pb dating GEOCHEMISTRY Rb metallogeny Gariatong tibet
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Call for Papers:Special Issue of China Finance Review International Artificial Intelligence and Finance:Modern Approaches and Implications
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《系统管理学报》 CSCD 北大核心 2023年第5期1117-1118,共2页
Special Issue Guest Editors·Michael Gofman,Senior Lecturer in Finance at the Hebrew University of Jerusalem·Zhao Jin,Assistant Professor of Finance,CKGSB Special Issue Information Artificial intelligence(AI)... Special Issue Guest Editors·Michael Gofman,Senior Lecturer in Finance at the Hebrew University of Jerusalem·Zhao Jin,Assistant Professor of Finance,CKGSB Special Issue Information Artificial intelligence(AI)is becoming an increasingly important tool for fund managers,CFOs,regulators,traders,investors,and entrepreneurs.The generative AI revolution that started with the ChatGPT. 展开更多
关键词 BECOMING GENERATIVE issue
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Psychological Issues among Women Undergoing Fertility Treatment in a Specialist Fertility Hospital, South East Nigeria
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作者 Johnson Akuma Obuna Monday Nwite Igwe 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第4期681-692,共12页
Introduction: In Nigeria, a major reason for marriage is procreation and married couples look forward to having children within a year or two of marriage. The inability to achieve conception and subsequently have a ch... Introduction: In Nigeria, a major reason for marriage is procreation and married couples look forward to having children within a year or two of marriage. The inability to achieve conception and subsequently have a child among couples may lead to psychological complications. Objective: This study assessed the psychological impact of infertility and its management on women receiving treatment at a Fertility Specialist Hospital in a poor resource setting. Methods: This was a cross-sectional study of 376 consenting married women who sought and received fertility treatment at a private Fertility Specialist Hospital, located at Abakaliki, South-East Nigeria between May 1, 2017 and May 31, 2022. Socio-demographic and Structured questionnaires were administered to the participants over a 5-year period. Results: The mean age of the women at presentation was 36.9 (±7.2 SD) years. The majority of the women (227) presented with secondary infertility accounting for 60.4%, while the rest had primary infertility (χ<sup>2</sup> = 16.18, P = 0.001). Male-only factor infertility accounted for 22.9% of all the infertility cases, female-only factor 21.3% while both (male and female factors co-existing) accounted for 52.7% of all the cases. The commonest cause of infertility in the study was poor sperm parameters (176) accounting for 46.8% of cases, tubal factor 19.1% and anovulatory factor 22.3% (χ<sup>2</sup> = 214.21, P = 0.001). Three hundred and thirty four (88.8%) felt depressed, 266 (70.7%) felt guilty about the past, and 222 (59.0%) had suicidal tendencies because of the infertility ordeal. Two hundred and fifty one (66.8%) felt inferior, 237 (63.0%) cried often and 174 (46.3%) were socially withdrawn. However, 10.4% of the women felt satisfied and well. These negative psychological feelings were statistically significant. Concerning the effect on marriage, the closeness of couples was reduced significantly in 57.7%, 62.8% had reduced coital intimacy, 79.3% had frequent quarrel and misunderstanding, 27.9% had threats of divorce while 4.5% had actually divorced and 11.% separated. However, there was no negative effect of infertility in 8.8% of couples. Conclusion: Psychological issues associated with infertility and its management in women include feelings of depression, guilt feelings, suicidal ideation, weeping episodes, social withdrawal, feelings of inferiority, reduced libido, and poverty of intimacy with frequent quarrels and misunderstanding. Women appear to bear more of the psychological issues associated with infertility. Early marriage on the part of the women, preservation of their reproductive youthful ages, and a better understanding of the concept of infertility by the couple will not only reduce the prevalence of infertility but will also reduce the dangerous psychological issues associated with infertility. 展开更多
关键词 INFERTILITY Psychological issues Fertility Treatment Fertility Hospital NIGERIA
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Call for Papers:Special Issue of China Finance Review International Artificial Intelligence and Finance:Modern Approaches and Implications
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《系统管理学报》 CSCD 北大核心 2023年第6期1349-1350,共2页
Special Issue Guest Editors·Michael Gofman,Senior Lecturer in Finance at the Hebrew University of Jerusalem·Zhao Jin,Assistant Professor of Finance,CKGSB Special Issue Information Artificial intelligence (AI... Special Issue Guest Editors·Michael Gofman,Senior Lecturer in Finance at the Hebrew University of Jerusalem·Zhao Jin,Assistant Professor of Finance,CKGSB Special Issue Information Artificial intelligence (AI) is becoming an increasingly important tool for fund managers,CFOs,regulators,traders,investors,and entrepreneurs.The generative AI revolution that started with the ChatGPT,has spurred a gale of creative destruction that poses risks and opportunities to most firms in theworld.This general-purpose technology changes the tools that professional and retail investors use to collect,analyze,and process structured and unstructured data. 展开更多
关键词 BECOMING GENERATIVE issue
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Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and Sr Isotopic Analysis of Scheelite 被引量:1
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作者 WANG Yiyun WU Zhishan +8 位作者 CHEN Wenqing DU Qing’an TANG Liwei SHI Hongzhao MA Guotao ZHANG Zhi LIANG Wei WU Bo MIAO Hengyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期117-131,共15页
The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controver... The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and a slow rise in pH value.Additionally,the high Mo and low Sr contents in the scheelite are consistent with typical characteristics of magmatic-hydrothermal scheelite.Therefore,considering the geological features of the deposit,the geochemical characteristics of scheelite and the O-H isotope data published previously,it can be concluded that the genesis of the Nuri deposit belongs to porphyry-skarn deposit. 展开更多
关键词 trace elements in situ Sr isotopes tungsten mineralization Gangdese metallogenic belt tibet
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Preface to the Special Issue on the 2019—2023 China National Report on Geodesy
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作者 Yamin Dang 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第3期F0002-F0002,I0001,共2页
This Special Issue presents the progress of research and development on geodesy in China during the time period from January 2019 to June 2023.It was submitted,on behalf of the Chinese National Committee for Internati... This Special Issue presents the progress of research and development on geodesy in China during the time period from January 2019 to June 2023.It was submitted,on behalf of the Chinese National Committee for International Association of Geodesy(CNC-IAG),to the IAG General Assembly at the 28th IUGG General Assembly held in Berlin,Germany,July 11—20,2023.It is hoped that this national report would be of help for Chinese scientists in exchanging the results and ideas in the research,development and application of geodesy with scientists all over the world. 展开更多
关键词 behalf issue GEODE
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A STUDY ON THE CHRONOLOGY OF COINAGE ISSUED BY TIGRANES Ⅱ
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作者 Roy Arakelian Maxime K.Yevadian 《Journal of Ancient Civilizations》 2023年第1期21-57,125,126,共39页
The question of Tigranes II's coinage and its chronology is one of the main difficulties for Artaxiad numismatics.These coins account for over half of all coin types issued by all the kings of this dynasty over a ... The question of Tigranes II's coinage and its chronology is one of the main difficulties for Artaxiad numismatics.These coins account for over half of all coin types issued by all the kings of this dynasty over a period of almost two centuries(189 BC-AD 16).The abundance and wide range of types,monograms,legends,and tiara shapes have led to differing and sometimes contradictory classifications. 展开更多
关键词 CHRONOLOGY SOMETIMES issued
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Meaning in Life and Mental Health Issues in Older Adults:A Meta-Analysis
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作者 Shu Nie Jiyoon Lim +2 位作者 Xintian Xu Lei Zheng Yiqun Gan 《International Journal of Mental Health Promotion》 2023年第9期971-984,共14页
This study aims to be the first to use meta-analysis to explore the relationship between meaning in life(MIL)and mental health issues among older adults.A meta-analysis was conducted using six databases,resulting in 1... This study aims to be the first to use meta-analysis to explore the relationship between meaning in life(MIL)and mental health issues among older adults.A meta-analysis was conducted using six databases,resulting in 16 studies with 5,074 participants in total.The“metacor”and“forestplot”packages in R-Studio were used for data analysis.The total effect was calculated using a random-effects model,with I2=86%in the heterogeneity test.The results showed a moderate negative correlation between MIL and mental health issues among older adults,with an average effect of−0.37.Five potential moderating variables were examined:the conceptualization of MIL(value vs.purpose),region(Asian vs.Western countries),residence status(community vs.nursing home vs.hospital),types of mental health issues,and evaluation methods(clinical vs.non-clinical).The first four had no significant moderating effect.The mean correlation coefficients between mental health issues and value/purpose were−0.49/−0.33;the mean correlation coefficients in Asian countries and Western countries were−0.48 and−0.34;the mean correlation coefficients among participants living in community/nursing home/mixed status were−0.33/−0.40/−0.40;the mean correlation coefficients between MIL and depression/others were−0.37/−0.35;however,the negative relationship between MIL and mental health issues was stronger when non-clinical evaluations(self-report only)were used.Specifically,the mean correlation coefficient for non-clinical evaluations was−0.42 and for clinical evaluations was−0.29.This study is the first meta-analysis to identify the negative correlation between older adults’MIL and mental health issues.Significant moderating effects of evaluation methods were found. 展开更多
关键词 Meaning in life mental health issues DEPRESSION ANXIETY META-ANALYSIS older adults
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Mineral Geochemistry of Apatite in the Jiama PorphyrySkarn Deposit,Tibet and its Geological Significance
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作者 YANG Yang TANG Juxing +8 位作者 ZHANG Zebin TANG Pan XIE Fuwei RAN Fengqin YANG Zongyao YANG Huaichao BAI Yun SUN Miao QI Jing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期399-415,共17页
The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic system.However,the mineral chemi... The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic system.However,the mineral chemistry of its accessory minerals remains under-examined,posing challenges for resource assessment and ore prospecting.Utilizing electron microprobe analysis and LA-ICP-MS analysis,this study investigated the geochemical characteristics of apatite in ore-bearing granite and monzogranite porphyries,as well as granodiorite,quartz diorite,and dark diorite porphyries in the deposit.It also delved into the diagenetic and metallogenic information from these geochemical signatures.Key findings include:(1)The SiO_(2) content,rare earth element(REE)contents,and REE partition coefficients of apatite indicate that the dark diorite porphyry possibly does not share a cogenetic magma source with the other four types of porphyries;(2)the volatile F and Cl contents in apatite,along with their ratio,indicate the Jiama deposit,formed in a collisional setting,demonstrates lower Cl/F ratios in apatite than the same type of deposits formed in a subduction environment;(3)compared to non-ore-bearing rock bodies in other deposits formed in a collisional setting,apatite in the Jiama deposit exhibits lower Ce and Ga contents.This might indicate that rock bodies in the Jiama deposit have higher oxygen fugacity.Nevertheless,the marginal variation in oxygen fugacity between ore-bearing and non-ore-bearing rock bodies within the deposit suggests oxygen fugacity may not serve as the decisive factor in the ore-hosting potential of rock bodies in the Jiama deposit. 展开更多
关键词 APATITE METALLOGENESIS mineral geochemistry PORPHYRY JIAMA tibet
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Preface to Special Issue on Towards High Performance Ga_(2)O_(3) Electronics: Epitaxial Growth and Power Devices(Ⅰ)
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作者 Genquan Han Shibing Long +2 位作者 Yuhao Zhang Yibo Wang Zhongming Wei 《Journal of Semiconductors》 EI CAS CSCD 2023年第6期4-6,共3页
There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power ... There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power electronic applications. Specially, benefiting from its ultra-high bandgap of around 4.8 eV, it is expected that the emerging Ga_(2)O_(3) technology would offer an exciting platform to deliver massively enhanced device performance for power electronics and even completely new applications. 展开更多
关键词 Epitaxial Growth and Power Devices Preface to Special issue on Towards High Performance Ga_(2)O_(3)Electronics POWER
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Core Issues in Design of Tibetan Grassland Ecological Compensation Mechanism
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作者 Tianping LIU Yanjun MIAO Qianlu SUN 《Asian Agricultural Research》 2016年第12期37-40,共4页
Scientific grassland ecological compensation mechanism is favorable for improving the grassland ecological environment and promote the sustainable development of animal husbandry. Combined with actual situations of Ti... Scientific grassland ecological compensation mechanism is favorable for improving the grassland ecological environment and promote the sustainable development of animal husbandry. Combined with actual situations of Tibet,this paper discussed core issues in the design of grassland ecological compensation mechanism,including compensation purpose,compensation subject,compensation object,compensation standard,and compensation method. It pointed out that the design of mechanism is a complex and systematic project. Each issue is complex and varied. The government at all levels should be cautious and make scientific treatment,and should not apply a single solution for all issues. 展开更多
关键词 Grassland ecological compensation Compensation mechanism Core issues tibet
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Present-day Upper-crustal Strain Rate Field in Southeastern Tibet and its Geodynamic Implications:Constraints from GPS Measurements with ABIC Method
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作者 YANG Shaohua PAN Jiawei +1 位作者 LI Haibing SHI Yaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期265-275,共11页
The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic ne... The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic networks.If the discrete observed velocity field is obtained,the velocity related fields,such as dilatation rate and maximum shear strain rate,can be estimated by applying varied mathematical approaches.This study applied Akaike's Bayesian Information Criterion(ABIC)method to calculate strain rate fields constrained by GPS observations in the southeast Tibetan Plateau.Comparison with results derived from other three methods revealed that our ABIC-derived strain rate fields were more precise.The maximum shear strain rate highlighted the Xianshuihe–Xiaojiang fault system as the main boundary for the outward migration of material in southeastern Tibet,indicating rotation of eastern Tibet material around the eastern Himalaya rather than whole extrusion along a fixed channel.Additionally,distinct dilatation rate patterns in the northeast and southwest regions of the fault system were observed.The northeast region,represented by the Longmenshan area,exhibited negative dilatational anomalies;while the southwest region,represented by the Jinsha River area north of 29°N,displayed positive dilatational anomalies.This indicates compression in the former and extension in the latter.Combined with deep geophysical observations,we believe that the upper and lower crusts of the Jinsha River area north of 29°N are in an entire expanding state,probably caused by the escape-drag effect of material.The presence of a large,low-viscosity region south of 29°N may not enable the entire escape of the crust,but instead result in a differential escape of the lower crust faster than the upper crust. 展开更多
关键词 strain rate differential escape ABIC GPS southeastern tibet
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Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power
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作者 Zhiguo SUN Li GAO +3 位作者 Yuanpeng SUN Guangchao CAO Xinying ZHOU Xiaoqiang LI 《Asian Agricultural Research》 2024年第3期18-24,共7页
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod... In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries. 展开更多
关键词 PAIRING ASSISTANCE to tibet Southern tibet Shannan CITY Nyingchi CITY AGRICULTURAL high-quality development AGRICULTURAL power
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Texture and Geochemistry of Multi-stage Hydrothermal Scheelite in the Mamupu Cu-Au-Mo(-W)Deposit,Eastern Tibet:Implications for Tungsten Mineralization in the Yulong Belt
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作者 ZHANG Xiaoxu TANG Juxing +7 位作者 LIN Bin WANG Qin HE Liang YAN Gang SHAO Rui WU Qiang DU Qiu ZHAXI Pingcuo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期701-716,共16页
Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPCB),Tibet.This study reports the results of cathodoluminescence,trace ... Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPCB),Tibet.This study reports the results of cathodoluminescence,trace element and Sr isotope analyses of Mamupu scheelite samples,undertaken in order to better constrain the mechanism of W mineralization and the sources of the ore-forming fluids.Three different types of scheelite are identified in the Mamupu deposit:scheelite A(Sch A)mainly occurs in breccias during the prograde stage,scheelite B(Sch B)forms in the chlorite-epidote alteration zone in the retrograde stage,while scheelite C(Sch C)occurs in distal quartz sulfide veins.The extremely high Mo content and negative Eu anomaly in Sch A represent high oxygen fugacity in the prograde stage.Compared with ore-related porphyries,Sch A has a similar REE pattern,but with higher ΣREE,more depleted HREE and slightly lower(^(87)Sr/^(86)Sr)i ratios.These features suggest that Sch A is genetically related to ore-related porphyries,but extensive interaction with carbonate surrounding rocks affects the final REE and Sr isotopic composition.Sch B shows dark(Sch B-I)and light(Sch B-II)domains under CL imaging.From Sch B-I to Sch B-II,LREEs are gradually depleted,with MREEs being gradually enriched.Sch C has the highest LREE/HREE ratio,which indicates that it inherited the geochemical characteristics of fluids after the precipitation of HREE-rich minerals,such as diopside and garnet,in the early prograde stage.The Mo content in Sch B and Sch C gradually decreased,indicating that the oxygen fugacity of the fluids changed from oxidative in the early stages to reductive in the later,the turbulent Eu anomaly in Sch B and Sch C indicating that the Eu anomaly in the Mamupu scheelite is not solely controlled by oxygen fugacity.The extensive interaction of magmatic-hydrothermal fluids and carbonate provides the necessary Ca^(2+)for the precipitation of scheelite in the Mamupu deposit. 展开更多
关键词 SCHEELITE GEOCHEMISTRY Mamupu Cu deposit Yulong porphyry copper belt eastern tibet
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