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Zircon U-Pb dating of metagabbro masses from the Liwu Group Complex within the Taka dome:Geochronological constraints on the Indosinian-Yanshanian tectonic events in western Sichuan,China
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作者 Hong-chao Zhang Hong-bing Zhou +7 位作者 Bo Yan Chong-bo Sun Yue-zhong Wang Yun-chuan Zhao Yao Wen Ren-liang Cao Yang Qin Hong-qi Tan 《China Geology》 2025年第4期865-868,I0004-I0006,共7页
1.Objective The Songpan-Ganze terrane is a key region for understanding the tectonic evolution of the Tibetan Plateau and the Yangtze Craton.The Songpan-Ganzi complex comprises a thick succession of deformed Ladinian-... 1.Objective The Songpan-Ganze terrane is a key region for understanding the tectonic evolution of the Tibetan Plateau and the Yangtze Craton.The Songpan-Ganzi complex comprises a thick succession of deformed Ladinian-Norian turbidites(ca.230-203 Ma),covering about 200000 km^(2)of the eastern Tibet Plateau with a volume of approximately 2.0×10^(6)km^(3)(Fig.1a).Furthermore,this complex has over 100 Permian-Cenozoic felsic plutons. 展开更多
关键词 u pb dating INDOSINIAN zircon METAGABBRO taka dome YANSHANIAN liwu group complex tectonic events
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Surrounding rock deformation characteristics and control strategies during passing through abandoned roadway group
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作者 YANG Feng SUN Qiang +2 位作者 ZHOU Nan CHEN Yong WEI Yongqi 《Journal of Mountain Science》 2025年第7期2707-2722,共16页
The disorderly mining activities and irrational layout in underground coal mines have left a large number of adjacent abandoned roadways.During the process of a working face passing through abandoned roadways,these st... The disorderly mining activities and irrational layout in underground coal mines have left a large number of adjacent abandoned roadways.During the process of a working face passing through abandoned roadways,these structures are prone to varying degrees of damage,with frequent occurrences of roof leakage and induced rock burst accidents,significantly impacting subsequent mining operations and safe production.To address these issues,this study investigates the surrounding rock deformation patterns during fully mechanized mining face passage through abandoned roadway clusters.Specific countermeasures were systematically summarized according to different occurrence characteristics of abandoned roadways.Through mechanical analysis,the critical unstable width of coal pillars was determined to be approximately 16.1~16.8 m.A three-dimensional numerical model was established based on 17 abandoned roadways with various shapes and occurrences in the working face.Simulation results indicate severe deformation and failure in roof rock layer roadways,while floor roadways exhibit relatively minor damage.Notably,when the distance between abandoned roadways and the coal seam exceeds 8 m,almost no damage occurs.Three technical measures for passing through abandoned roadway group was proposed according to their occurrence characteristics and implemented in engineering practice.Field applications demonstrate limited coal stress variations and weak strata pressure manifestations during the crossing process,ensuring safe passage through abandoned roadway clusters.This achievement enables efficient and safe crossing of abandoned roadway group in fully mechanized mining faces,enhances coal recovery rates,and provides practical engineering references for similar geological conditions. 展开更多
关键词 Abandoned roadway group 3D abandoned roadway model Numerical simulation Control strategies Engineering application
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Value Evaluation for Urban Medical Groups in China:A Case From Dapeng New District in Shenzhen
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作者 Yan Cui Leiyu Shi +2 位作者 Shilan Tang Yansui Yang Lijie Ren 《Health Care Science》 2025年第3期206-214,共9页
Background:An urban medical group in Dapeng New District was established in 2017 with the objective of enhancing outcomes for common diseases and reinforcing primary care by integrating high‐level hospitals with prim... Background:An urban medical group in Dapeng New District was established in 2017 with the objective of enhancing outcomes for common diseases and reinforcing primary care by integrating high‐level hospitals with primary health services.This study aimed to evaluate the performance of the urban medical group using the triangular value chain framework.Methods:The evaluation was conducted using the Donabedian model,focusing on three key dimensions:safety and quality,accessibility,and affordability.Longitudinal data were collected from 2016 to 2022 through government annual reports,the medical insurance bureau,and hospital information systems.Preprogram and postprogram outcome measurements were compared to assess differences and trends,providing a clear picture of the program's effectiveness.Results:Accessibility improved significantly,with the number of hospital beds per 1000 residents increasing from 2.62 in 2017 to 3.76 in 2022.The availability of general practitioners(GPs)also rose markedly,from 0 per 10,000 residents in 2017 to 6.27 in 2022.Regarding safety and quality,the proportion of complex medical procedures conducted within the New District expanded substantially,from 7.35%in 2017 to 38.11%in 2021.Additionally,there was an enhancement in the standardized management rate of chronic diseases.Affordability assessments showed that the proportion of medical income derived from the medical insurance fund increased by nearly 22.81 percentage points between 2012 and 2021.By 2021,75.02%of medical patients were covered by medical insurance,representing an increase of approximately 44 percentage points from 31.19%in 2012.Conclusions:The implementation of the urban medical group in Dapeng New District has led to substantial improvements in healthcare accessibility,safety and quality,and affordability.Future initiatives will focus on advancing the“Dapeng Mode”to generate exemplary healthcare outcomes and minimize disparities in basic health services and health status between urban and rural populations.The reform agenda includes piloting payment reforms and innovative payment models within the Dapeng group,complemented by a health assessment and performance incentive system aimed at encouraging healthcare institutions to prioritize health management. 展开更多
关键词 Donabedian model integrated care medical consortium triangular value chain triple aims urban medical group value evaluation
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Impact of Consanguineous Marriage on Hearing and Language Disorders:Study Among a Group of Egyptian Children
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作者 Sherien A.Nasser Fatma Hussein +1 位作者 Heba Tallah Sherif Abd El Hady Nagwa A.Meguid 《Journal of Otology》 2025年第2期110-116,共7页
Background:Even though various research has demonstrated the connection between consanguinity and health issues,consanguineous marriage still common in Egypt with high prevalence rate 35.3%,23.5%in semi-urban and 17.7... Background:Even though various research has demonstrated the connection between consanguinity and health issues,consanguineous marriage still common in Egypt with high prevalence rate 35.3%,23.5%in semi-urban and 17.7%in urban areas.Methods:This study was conducted on 434native Arabic-speaking Egyptians children(3-10 years)who visited Special Needs Clinic at National Research Centre,among one year presenting with a hearing or/and language problem.They were subjected to psychometric assessment,Conners'Parent Rating Scales-Revised,Autism Diagnostic Interview Revised,Childhood Autism Rating Scale,audiological assessment,and Arabic Preschool Language Scale-4.Participants were classified into 6 subgroups according to the cause of language delay.We estimated the frequency and degree of consanguinity in each group and the association between consanguinity and hearing and language problems.Results:The prevalence of the consanguineous marriage in all participants(n=434)was31.6%with the mean inbreeding coefficient of 0.01208.First cousins'marriages were the most common type of consanguineous marriages(50.3%of consanguineous marriages).Among all participants in the 6 subgroups(n=434),language delay secondary to cognitive delay showed the highest percentage of consanguineous marriages(35%)followed by autism spectrum disorder(32.8%).No significant association between consanguinity and language problems.Among the 78 participants with sensorineural hearing loss,35.9%of consanguineous couples(no.=28 cases)were reported versus 64.1%of non-consanguineous couples(no.=50 cases).Conclusions:The Frequency of consanguineous marriages in our participants was 31.6%which was close to that reported in Egyptian population.Absence of significant association between consanguinity and language problems warrants further investigation and point to the role of genetic-environment interplay in cases of language delay. 展开更多
关键词 Consanguineous MARRIAGE HEARING LANGUAGE EGYPTIAN CHILDREN
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Synthesis,Performance,and Mechanism of Polycarboxylate Superplasticizers Containing Adsorption Groups
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作者 GUO Haoping WANG Peng +10 位作者 CHEN Jiang ZHU Yiping SHEN Xuetao LOU Rongrong ZHU Senjie XU Xingen LIU Yuan LIU Ke SONG Shaomin LI Fei GE Dongliang 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期780-791,共12页
This article presents a preparation method for a tailing sand-specific polycarboxylate superplasticizer(AT9)containing multifunctional adsorption groups.By designing multifunctional adsorption groups(-COOH)as side cha... This article presents a preparation method for a tailing sand-specific polycarboxylate superplasticizer(AT9)containing multifunctional adsorption groups.By designing multifunctional adsorption groups(-COOH)as side chains grafted onto the main chain of conventional polycarboxylate ether,the antiadsorption effect is achieved.AT9 was characterized by gel permeation chromatography,and its performance was systematically evaluated in various tailings sand-cement mortar systems.A comparison was made between AT9 and traditional PCE in terms of their effects on the workability of concrete,and the interaction mechanism between AT9 and clay in cementitious systems was discussed.The results indicate that AT9 enhances the adsorption and dispersion effects of polycarboxylate superplasticizers on cement particles,and increases steric hindrance,thereby avoids intercalation adsorption of tailings sand,improves its water-reducing and slump-retaining performance,and also contributes to the strength enhancement of concrete in later stages. 展开更多
关键词 polycarboxylate superplasticizer molecular design tailings sand highly adsorptive CONCRETE
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Trends in prevalence and burden of depressive disorders in Iran at national and subnational levels: estimates based on sex and age groups
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作者 Sohrab Amiri Moien A B Khan 《General Psychiatry》 2025年第3期199-207,共9页
Background Mental disorders rank among the leading contributors to the global disease burden, with depressive disorders being among the most prevalent.Aims The objective of this study is to examine the prevalence, inc... Background Mental disorders rank among the leading contributors to the global disease burden, with depressive disorders being among the most prevalent.Aims The objective of this study is to examine the prevalence, incidence and years lived with disability (YLDs) associated with depressive disorders, particularly major depressive disorder and dysthymia, in Iran from 1990 to 2021. To achieve this, the research focused on analysing these metrics across various dimensions, including temporal trends, sex differences, age categories and subnational regions.Methods The data used in this study are sourced directly from the Institute for Health Metrics and Evaluation, ensuring that the information is both authoritative and reliable. All-age count estimates and age-standardised rates (per 100 000) were calculated for prevalence, incidence and YLDs. The disease burden indicators were analysed for the period spanning from 1990 to 2021, stratified by sex, age and location. The percentage change between 1990 and 2021 was also documented. The 95% uncertainty interval (UI) was reported for each of the reported estimates.Results The prevalence of depressive disorders in Iran demonstrated a notable upward trend from 1990 to 2021, with the rate of growth being particularly pronounced within the country. The age-standardised prevalence rate per 100 000 individuals for depressive disorders in Iran was 5609 (95% UI 4810 to 6488). By 2021, the number of depression cases in Iran reached 5.2 million, which is approximately 2.37 times the figure reported in 1990. The prevalence of depressive disorders was notably higher among females compared with males. The age-standardised prevalence rate per 100 000 individuals for males was 4184 (95% UI 3545 to 4929). For females, this figure was significantly greater, reaching 7077 (95% UI 6115 to 8172). Out of the total reported cases of depressive disorders in Iran, 3.2 million were observed in females, while males accounted for 2 million cases.Conclusions The findings highlighted the considerable impact of depressive disorders in Iran, both nationally and regionally, while also revealing variations across sex and age groups. Given the shifts in the demographic structure and the growing burden of these disorders, it is essential to prioritise screening initiatives, education programmes and strategies aimed at enhancing mental health awareness and ensuring improved access to mental health services in health policy planning. 展开更多
关键词 years lived disability sex differences Iran major depressive disorder BURDEN PREVALENCE depressive disorders mental disorders
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Research on the path of effective management of participation in joint-venture railway companies by China railway group 被引量:1
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作者 Shaoni Zhou Zhitian Zhou Chenxia Kang 《Railway Sciences》 2024年第4期530-539,共10页
Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway G... Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway Group in managing participation in joint-venture railway companies.The study seeks to propose specific approaches to ensure the effective management of these companies,thereby maximizing the benefits of the regional restructuring and supporting the development of a strong transportation country and a modern infrastructure system.Design/methodology/approach-Based on the change in the shareholding relationship between China Railway Group and the joint-venture railway companies,and considering the current situation of the regional restructuring of these companies,as well as the insights from existing literature and typical case studies,this paper proposes some specific paths for effective management of joint-stock railway companies which China Railway Group participated in.Findings-The problems in participation management are the unclear dual leadership role of the party committee,the lack of discourse power,the lack of synergy between shareholders,the increasing risk of sustainable operation of the loss-making companies and the role of dispatched personnel is not fully played.Based on the theories,combined with the existing research and practical cases,the paper proposed specific approaches,such as perfecting top-level system design,maintaining the discourse power,carrying out differentiated management,arranging personnel rationally,arranging shareholders synergy,and innovating methods to provide references for China Railway Group’s subsequent management of joint venture railway companies.Originality/value-This paper contributes to the existing literature by providing a comprehensive analysis of the challenges faced by China Railway Group in managing participation in joint-venture railway companies following the regional restructuring.The study offers novel insights and practical recommendations for addressing these challenges.The findings can serve as valuable references for China Railway Group’s subsequent management of joint-venture railway companies which participated in,as well as for other stateowned enterprises facing similar challenges in managing their joint ventures. 展开更多
关键词 China railway group Joint venture railway companies Participated relationship Effective management
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Genetic mechanism of body size variation in groupers:Insights from phylotranscriptomics
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作者 Wei-Wei Zhang Zhuo-Ying Weng +5 位作者 Xi Wang Yang Yang Duo Li Le Wang Xiao-Chun Liu Zi-Ning Meng 《Zoological Research》 SCIE CSCD 2024年第2期314-328,共15页
Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within ... Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within the fish genus Epinephelus with evident divergence in body size,providing an excellent opportunity to investigate the genetic basis of body size variation in vertebrates.Herein,we performed phylotranscriptomic analysis and reconstructed the phylogeny of 13 epinephelids originating from the South China Sea.Two genetic clades with an estimated divergence time of approximately 15.4 million years ago were correlated with large and small body size,respectively.A total of 180 rapidly evolving genes and two positively selected genes were identified between the two groups.Functional enrichment analyses of these candidate genes revealed distinct enrichment categories between the two groups.These pathways and genes may play important roles in body size variation in groupers through complex regulatory networks.Based on our results,we speculate that the ancestors of the two divergent groups of groupers may have adapted to different environments through habitat selection,leading to genetic variations in metabolic patterns,organ development,and lifespan,resulting in body size divergence between the two locally adapted populations.These findings provide important insights into the genetic mechanisms underlying body size variation in groupers and species differentiation. 展开更多
关键词 Phylotranscriptomics GROUPER Body size Rapidly evolving genes(REGs) Positively selected genes(PSGs)
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Phytoplankton functional groups in Poyang Lake:succession and driving factors 被引量:2
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作者 Jinfu LIU Haoyue ZOU +10 位作者 Feng DENG Yutian LIU Wei LI Jinying XU Songping LIU Qiang WU Xiaoliang ZHANG Fagen WENG Qi HUANG Hailin YOU Yuwei CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第6期1764-1776,共13页
Phytoplankton functional groups have gained increasing attention in recent years.To understand the composition of phytoplankton functional groups in Poyang Lake and their drivers,field investigations were conducted ov... Phytoplankton functional groups have gained increasing attention in recent years.To understand the composition of phytoplankton functional groups in Poyang Lake and their drivers,field investigations were conducted over three years:2013,2014,and 2016.Phytoplankton were dominated by diatoms,contributing from 20.19%to 57.57%of the total biomass,followed by cyanobacteria,9.81%-39.98%.Microcystis sp.and Anabaena sp.were the dominant species among cyanobacteria.Twenty-six functional groups were identified among 72 genera or species,and fiver groups(P,B,MP,H1,and G)were categorized dominant.All of dominant groups except H1 were tolerate highly fluctuating mixing intensities and showed a typical monthly succession variation.Water temperature,water level,and nutrients are key drivers for the variation of phytoplankton communities at taxonomic and functional levels.Both of redundancy and variation partitioning analyses showed that environmental variables might explain functional groups better than taxonomic communities,implying that the functional groups were more advantageous in showing the effects of environmental conditions than taxonomic compositions.Hydrological conditions have a crucial influence on phytoplankton assemblage dynamics in highly variable water regime lakes,but not in the largest ones.The functional groups method is suitable for identifying the spatial and seasonal characteristics of aquatic environments that significantly affected by water regimes. 展开更多
关键词 cyanobacteria bloom light availability nutrients dilution water level Poyang Lake
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Multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study 被引量:1
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作者 Oktay Özman Hacı M.Akgül +5 位作者 Cem Başataç Önder Çınar Eyüp B.Sancak Cenk M.Yazıcı Bülent Önal Haluk Akpınar 《Asian Journal of Urology》 CSCD 2024年第1期80-85,共6页
Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for ... Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively included.Firstly,patients were compared after 1:1 propensity score matching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 patients).Then all UAS+patients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 Fr.Primary outcomes of the study were the success and complications of RIRS.Results:Stone-free rate of UAS+patients(86.2%)was significantly higher than UAS−patients(70.1%)after propensity score matching(p=0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;p<0.001).Postoperative complications of UAS+patients(11.5%)were significantly lower than UAS−patients(27.6%)(p=0.01).Complications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p=0.09).UAS usage was an independent factor predicting stone-free status or peri-and post-operative complications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,respectively).Conclusion:Use of UAS in RIRS may increase stone-free rates,which also increase with higher caliber UAS.UAS usage may reduce complications;however,complications seemingly increase with higher UAS calibration. 展开更多
关键词 STONE Retrograde intrarenal surgery Ureteral access sheath UROLITHIASIS Kidney
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Patients Involved in Funding Research.A Look Back at the Unique Experience of the ECLAIR Working Group of Canceropole CLARA
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作者 Julien Biaudet Lisa Laroussi-Libeault +2 位作者 Mauricette Michallet Laurie Panse Raymond Merle 《Psycho-Oncologie》 SCIE 2024年第1期17-22,共6页
This article aims to share an innovative experience of organizing and funding research involving those most directly affected:patients.The“ECLAIR”working group of the Canceropole Lyon Auvergne-Rhone-Alpes(CLARA)was ... This article aims to share an innovative experience of organizing and funding research involving those most directly affected:patients.The“ECLAIR”working group of the Canceropole Lyon Auvergne-Rhone-Alpes(CLARA)was created at the end of 2020 with the goal of contributing to the development of a call for projects on the patient experience in oncology,which was launched in January 2021.Initially composed of 8 members,including 7 patients,coordinated by a project manager from CLARA,the ECLAIR working group actively participated in drafting the specifications of the call for projects,developing the eligibility criteria for applications,revising the evaluation and selection criteria for projects,and monitoring the selected projects.This experience was repeated twice.With significant freedom of action,the working group made two decisions that strongly demonstrate the commitment to supporting research partnerships and the active involvement of those affected:firstly,by making partnership a mandatory requirement for the eligibility of applications,and secondly,by conducting the selection of projects themselves,after an independent scientific evaluation phase.Seeking to shed light on the“black box”of partnership,the article also presents the concrete modalities of interaction among the working group members,the adjustments made between different editions of the call for projects,and the relationships maintained with CLARA. 展开更多
关键词 Cancer research public and patient involvement research funding participatory research healthcare democracy
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VANET Security through Group Broadcast Encryption
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作者 Eric Eduardo Bunese Eduardo Todt Luiz Carlos Pessoa Albini 《Journal of Computer and Communications》 2020年第8期22-35,共14页
VANET security is an evolving topic in mobile networks, as providing a secure layer of communications in such a dynamic and fast network is a challenge. The work presented in this article was conducted in order to ver... VANET security is an evolving topic in mobile networks, as providing a secure layer of communications in such a dynamic and fast network is a challenge. The work presented in this article was conducted in order to verify and evaluate the feasibility of applying group broadcast cryptography to the VANET environment, as an attempt to gain performance by decreasing the number of messages in the wireless network. Group broadcast is a symmetric/asymmetric hybrid cryptography method, aiming to merge the best of the two approaches without their major drawbacks. Simulations were set-up and run using the ONE simulator, comparing the usage of the three different cryptography approaches for VANETs. Results consider the number of connections, the number messages and the number of revocation messages per day. The resulting data promises that group broadcast encryption can be used to simplify the encrypting phase, reduce required storage and significantly decrease the number of messages in the network. 展开更多
关键词 VANET Security Group Broadcast Encryption Group Based VANET
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Finite Groups Whose Some Subgroups Are S-seminormal
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作者 王坤仁 《Northeastern Mathematical Journal》 CSCD 2004年第2期217-224,共8页
A subgroup H is called S-seminormal in a finite group G if H permutes with all Sylow p-subgroups of G with (p, |H| =1. The main object of this paper is to generalize some known results about finite supersolvable group... A subgroup H is called S-seminormal in a finite group G if H permutes with all Sylow p-subgroups of G with (p, |H| =1. The main object of this paper is to generalize some known results about finite supersolvable groups to a saturated formation containing the class of finite supersolvable groups. 展开更多
关键词 saturated formation generalized Fitting subgroup S-seminormal subgroup
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A Sufficient Condition for Mi-groups
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作者 何立国 朱刚 《Northeastern Mathematical Journal》 CSCD 2003年第4期371-374,共4页
In this note, we give a sufficient condition for Mi-group. In particular, we show that if a finite group G is the semidirect product of two subgroups with coprime orders, in which one is a Sylow tower group and its Sy... In this note, we give a sufficient condition for Mi-group. In particular, we show that if a finite group G is the semidirect product of two subgroups with coprime orders, in which one is a Sylow tower group and its Sylow subgroups are all abelian, and the other is an Mi-group and all of its proper subgroups are also Mi-groups, then G is an Mi-group. 展开更多
关键词 solvable group Mi-group semidirect product
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A review of the Birimian Supergroup-and Tarkwaian Group-hosted gold deposits of Ghana
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作者 Albertus J.B.Smith George Henry Susan Frost-Killian 《Episodes》 2016年第2期177-197,共21页
Ghana is the largest producer of gold in West Africa,a region with over 2,500 years of history with regards to gold production and trade.Modern exploration for and mining of gold in Ghana dates from 1874 with the esta... Ghana is the largest producer of gold in West Africa,a region with over 2,500 years of history with regards to gold production and trade.Modern exploration for and mining of gold in Ghana dates from 1874 with the establishment of the British Gold Coast Colony,which was followed in 1957 by the independence of Ghana and increased gold production since the early 1980s through Ghana’s Economic Recovery Plan.At the time of writing,gold production(108.2 tonnes or 3.48 million ounces[Moz]in 2014)accounted for approximately one-third of Ghana’s export revenues,with 36%of gold production coming from small-scale mining. 展开更多
关键词 Birimian Supergroup gold production Ghana gold deposits small scale mining Tarkwaian Group
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Stability control of gate groups in deep wells 被引量:8
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作者 GUO Zhi-biao GUO Ping-ye +1 位作者 HUANG Mao-hong LIU Yin-gen 《Mining Science and Technology》 EI CAS 2009年第2期155-160,共6页
In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:de... In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining district.Three reasons are proposed:deep high stress,improper roadway layout and support technology.The stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support technology.Our research method has been applied at the -1000 m level gate group in Qishan Coal Mine.Suitable countermeasures have been tested by field monitoring. 展开更多
关键词 deep gate group stability intensive design bolt-mesh-anchor truss support
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Petrology of Garnet Amphibolites from the Hualong Group: Implications for Metamorphic Evolution of the Qilian Orogen, NW China 被引量:3
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作者 Yilong Li Limin Zhao +3 位作者 Zhuoyang Li Biji Luo Jianping Zheng Fraukje M.Brouwer 《Journal of Earth Science》 SCIE CAS CSCD 2018年第5期1102-1115,共14页
The Qilian Orogen marks the junction of the North China, South China and Tarim cratons. The mechanism of continental growth during the formation of the orogen remains unclear. Based on detailed fieldwork, we present a... The Qilian Orogen marks the junction of the North China, South China and Tarim cratons. The mechanism of continental growth during the formation of the orogen remains unclear. Based on detailed fieldwork, we present a systematic study of petrography, mineral chemistry and phase equilibria of garnet amphibolites from the Hualong Group, which represents the Precambrian basement in the southern accretionary belt of the Qilian Orogen. The garnet amphibolites mainly consist of amphibole, plagioclase, garnet and quartz, with minor pyroxene, biotite and ilmenite. A peak stage of upper amphibolite facies to low-temperature granulite facies metamorphism and retrograde metamorphism in the amphibolite facies affected the samples. Garnet has a homogeneous composition of Alm66-71Grs14-17Prp9_12Sps3-s, amphibole is ferro-hornblende, biotite belongs to the ferro-biotite species and pyroxene is dominated by orthopyroxene with few clinopyroxene. Pseudosection modeling of the garnet amphibolite samples indicates clockwise P-T paths. The samples witness peak metamorphism at conditions of -4.9-6.3 kbar and -755-820 ℃ in the upper amphibolite facies to low- temperature granulite facies, and retrograde cooling and decompression at conditions of-2.5-3.1 kbar and -325-545 ℃. It is inferred that peak metamorphism with high temperature and low pressure occurred at ca. 450 Ma during northward subduction of the South Qilian oceanic crust beneath the central Qilian Block. When continental collision occurred between the central Qilian and the Qaidam blocks, the Hualong Block was aecreted onto the South Qilian accretionary complex and experienced amphibolite facies retrograde metamorphism at ca. 440 Ma. 展开更多
关键词 Qilian Orogen Hualong Group garnet amphibolite PETROLOGY metamorphic P-T path PerpleX.
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Molecular characterization of VP4,VP6,VP7 and NSP4 genes of group B rotavirus strains from outbreaks of gastroenteritis 被引量:1
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作者 Anismrita Lahon Shobha D Chitambar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第11期846-849,共4页
Objective:To characterize VP4,VP6,VP7 and NSP4 genes of representative GBR strains(NIV- 005625.MV-04622 and NIV-094456) delected as the major eliolngic agenl in the outbreaks of gastroenteritis in western India.Method... Objective:To characterize VP4,VP6,VP7 and NSP4 genes of representative GBR strains(NIV- 005625.MV-04622 and NIV-094456) delected as the major eliolngic agenl in the outbreaks of gastroenteritis in western India.Methods:Fecal specimens collected during the outbreaks of gastroenteritis were processed for RNA isolation.RT-PCR using GBR VP4.VP6.VP7 and NSP4 gene specific primers,nucleotide sequencing of the amplicons and phylogenetic analysis of the sequences.Results:Phylogenetic analysis of all of the VP4.VP6.VP7 and NSP4 gene sequences revealed clustering of GBR strains in Indian-Bangladeshi lineage of genotype G2 with 95.8%- 99.4%nucleotide and 97.3%-100.0%amino acid identities.However,all three strains showed the presence of unique amino acid substitutions in the VP4 protein suggesting alteration in the antigenicity of outbreak strains of GBR.The VP8* and VP5* regions of VP4 proteins showed respectively 0.5%-6.3%and 0.2%-1.1%amino acid divergence from human GBR strains of Indian-Bangladeshi lineage.Conclusions:These data confirm the reported variability of VP8* region and suggest the possible role of this region in the perpetuation of GBR infections in the environment.This is the first study to document the phylogenetic relationship of VP4,VP6.VP7 and NSP4 genes of GBR strains detected in the outbreaks of gastroenteritis from India with the CBR strains from other parts of world. 展开更多
关键词 Acute GASTROENTERITIS GROUP B ROTAVIRUS VP4 VP6 VP7 NSP4
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Petrology and Metamorphic P-T Paths of Metamorphic Zones in the Huangyuan Group,Central Qilian Block,NW China 被引量:3
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作者 Zhuoyang Li Yilong Li +2 位作者 Limin Zhao Jianping Zheng Fraukje M.Brouwer 《Journal of Earth Science》 SCIE CAS CSCD 2019年第6期1280-1292,共13页
The Central Qilian Block is a Precambrian block in the Qilian Orogen,which has long drawn international attention for the study of orogeny and continental dynamics.The Huangyuan Group in the Datong area is one of the ... The Central Qilian Block is a Precambrian block in the Qilian Orogen,which has long drawn international attention for the study of orogeny and continental dynamics.The Huangyuan Group in the Datong area is one of the Precambrian metamorphic basement units in the Central Qilian Block and reflects metamorphism in the Barrovian garnet zone and sillimanite zone from south to north.Based on detailed fieldwork,this study presents a systematic study of petrography,mineral chemistry and phase equilibria of schists and gneisses from the two metamorphic zones.The garnet metamorphic zone is composed of micaschist,garnet-bearing micaschist and felsic leptynite,with interlayered plagioclase amphibolite.The sillimanite metamorphic zone consists of garnet-bearing biotite micaschist,sillimanite-bearing biotite-plagioclase gneiss and felsic leptynite.Garnet from the garnet metamorphic zone shows growth zoning with increasing almandine and pyrope and decreasing spessartine from core to rim.Garnet from the sillimanite metamorphic zone is almost homogeneous.Towards the outer rim,the contents of almandine and pyrope slightly decrease and grossular slightly increase.Biotite in both metamorphic zones is ferro-biotite.Plagioclase is oligoclase in garnet metamorphic zone and andesine in sillimanite metamorphic zone.Phase equilibrium modeling of a sample from garnet metamorphic zone resulted in a clockwise P-T path with a prograde stage(4.5–5.0 kbar,520–530℃),a peak P stage(9.8–10.2 kbar,560–570℃),a stage of thermal relaxation(8.0–8.5 kbar,580–590℃)and finally a retrograde stage(6.8–7.0 kbar,560–580℃).Thermodynamic modeling of a sample from the sillimanite metamorphic zone indicates a prograde stage(5.5–6.0 kbar,540–550℃)and a peak stage(7.8–8.5 kbar,660–690℃).The results indicate that the Huangyuan Group experienced medium-pressure amphibolite-facies metamorphism,which resulted from continental-continental collision between the Qaidam Block and the Central Qilian Block. 展开更多
关键词 QILIAN BLOCK Huangyuan GROUP garnet ZONE SILLIMANITE ZONE P-T path thermodynamic modeling
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Excavation influence of triangular-distribution tunnels for wind pavilion group of a metro station 被引量:2
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作者 CHEN Tao ZHOU Kun +4 位作者 WEI Jun LIU Xiao-chun LIN Yu-liang ZHANG Jian SHEN Quan 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3852-3874,共23页
For the Guanshui Road Station tunnel project of Guiyang Metro Line 2,the wind pavilion group was moved out of the main tunnel to reduce the number of openings in the main tunnel,and the wind pavilion group was excavat... For the Guanshui Road Station tunnel project of Guiyang Metro Line 2,the wind pavilion group was moved out of the main tunnel to reduce the number of openings in the main tunnel,and the wind pavilion group was excavated in a triangular configuration at the entrance of the main tunnel.Based on the finite element software ABAQUS,a three-dimensional model is established to study the influence of different triangular-distribution tunnels excavation schemes on the surface settlement and tunnel stability.The objective of this study is to reveal the change rules of surface settlement,deformation and force in the support structures and the surrounding rock and identify the best excavation scheme for this tunnel configuration.Results show that to control the surface settlement and the deformation of the support structures,the optimal excavation sequence involves excavating the upper fresh air exhaust tunnel before the lower running tunnel.To control the stress of the support structures,the optimal excavation involves excavating the lower running tunnel before the upper fresh air exhaust tunnel.In this project,the most reasonable excavation sequence of the tunnel is from top to bottom.The most reasonable thickness of tunnel penetration is 5 m. 展开更多
关键词 station tunnel wind pavilion group finite element analysis tunnel and surrounding rock deformation stress analysis
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