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Spatial Patterns and Controlling Factors of Soil Organic Carbon and Total Nitrogen in the Three River Headwaters Region,China
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作者 CUI Qiao LI Zongxing +2 位作者 FENG Qi ZHANG Baijuan ZHAO Yue 《Chinese Geographical Science》 2025年第1期131-148,共18页
The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate ... The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate change on the structure,function,and services of the ecosystem.However,the spatial distribution and controlling factors of SOC and TN across various soil layers and vegetation types within this unique ecosystem remain inadequately understood.In this study,256 soil samples in 89 sites were collected from the Three River Headwaters Region(TRHR)in China to investigate SOC and TN and to explore the primary factors affecting their distribution,including soil,vegetation,climate,and geography factors.The results show that SOC and TN contents in 0-20,20-40,40-60,and 60-80 cm soil layers are 24.40,18.03,14.04,12.40 g/kg and 2.46,1.90,1.51,1.17 g/kg,respectively;with higher concentrations observed in the southeastern region compared to the northwest of the TRHR.One-way analysis of variance reveals that SOC and TN levels are elevated in the alpine meadow and the alpine shrub relative to the alpine steppe in the 0-60 cm soil layers.The structural equation model explores that soil water content is the main controlling factor affecting the variation of SOC and TN.Moreover,the geography,climate,and vegetation factors notably indirectly affect SOC and TN through soil factors.Therefore,it can effectively improve soil water and nutrient conditions through vegetation restoration,soil improvement,and grazing management,and the change of SOC and TN can be fully understood by establishing monitoring networks to better protect soil carbon and nitrogen. 展开更多
关键词 controlling factors different soil layers soil organic carbon(SOC) soil total nitrogen(TN) alpine ecosystem the Three River Headwaters region(TRHR) China
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Normothermic regional perfusion mobile teams in controlled donation after circulatory death pathway: Evidence and peculiarities
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作者 Chiara Lazzeri Manuela Bonizzoli +1 位作者 Giuseppe Feltrin Adriano Peris 《World Journal of Transplantation》 2024年第4期78-83,共6页
To facilitate the implementation of controlled donation after circulatory death(cDCD)programs even in hospitals not equipped with a local Extracorporeal Membrane Oxygenation(ECMO)team(Spokes),some countries and Italia... To facilitate the implementation of controlled donation after circulatory death(cDCD)programs even in hospitals not equipped with a local Extracorporeal Membrane Oxygenation(ECMO)team(Spokes),some countries and Italian Regions have launched a local cDCD network with a ECMO mobile team who move from Hub hospitals to Spokes for normothermic regional perfusion(NRP)implantation in the setting of a cDCD pathway.While ECMO teams have been clearly defined by the Extracorporeal Life Support Organization,regarding composition,responsibilities and training programs,no clear,widely accepted indications are to date available for NRP teams.Although existing NRP mobile networks were developed due to the urgent need to increase the number of cDCDs,there is now the necessity for transplantation medicine to identify the peculiarities and responsibility of a NRP team for all those centers launching a cDCD pathway.Thus,in the present manuscript we summarized the character-istics of an ECMO mobile team,highlighting similarities and differences with the NRP mobile team.We also assessed existing evidence on NRP teams with the goal of identifying the characteristic and essential features of an NRP mobile team for a cDCD program,especially for those centers who are starting the program.Differences were identified between the mobile ECMO team and NRP mobile team.The common essential feature for both mobile teams is high skills and experience to reduce complications and,in the case of cDCD,to reduce the total warm ischemic time.Dedicated training programs should be developed for the launch of de novo NRP teams. 展开更多
关键词 controlled donation after circulatory death Extracorporeal membrane oxygenation Normothermic regional perfusion Mobile teams Warm ischemia time
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Sequence Difference of Mitochondrial DNA Control Region and Genetic Differentiation of Cervinae in China 被引量:1
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作者 涂剑锋 邢秀梅 +2 位作者 徐佳萍 杨颖 杨福合 《Agricultural Science & Technology》 CAS 2011年第11期1717-1720,共4页
[Objective] The study aimed at analyzing Genetic Differentiation of Cervinae. [Method] The complete mitochondrial DNA control region of five species of Cervinae was determined by direct DNA sequencing. Homologous sequ... [Objective] The study aimed at analyzing Genetic Differentiation of Cervinae. [Method] The complete mitochondrial DNA control region of five species of Cervinae was determined by direct DNA sequencing. Homologous sequences of others Cervinae were gained from GenBank, and then analyzed through biology software. [Result] The lengths of their control region were 921-1 072 bp, the nucleotide content of T, A, C, and G was 32.1%, 30.2%, 22.7% and 15.0% separately. Genetic distance of each species ranged from 0.062-0.106, which belonged to level of inter-genus. The molecular phylogenetic tree indicated that red deer, skia deer and White-lipped Deer had close relationship, and they constituted one branch with sambar deer. Eld's deer and elk deer constituted the second branch, and hog deer constituted the third branch alone. [Conclusion] Hog deer and fallow deer should be incorporated in Cervus, divergence time is about 1.55-2.60 million years among Cervinae in China. 展开更多
关键词 Cervinae control region Sequence Analysis PHYLOGENY
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A Molecular Phylogeny of Macaca Based on Mitochondrial Control Region Sequences 被引量:8
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作者 李青青 张亚平 《Zoological Research》 CAS CSCD 北大核心 2004年第5期385-390,共6页
Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity ... Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity in M.thibetana were found.Based on the ML tree from control regions,species in our study can roughly be sorted into three species groups except for the phylogenetic position of M.fascicularis,i.e.,silenus group,including M.leonina;sinica group,including M.arctoides,M.assamensis,and M.thibetana;and fascicularis group,including M.mulatta and M.cyclopis.A discrepancy between earlier studies (Fooden & Lanyon,1989;Tosi et al,2003a;Deinard & Smith,2001;Evans et al,1999;Hayasaka et al,1996;Morales & Melnick,1998),our result supported the hypothesis that M.fascicularis diverged earlier than M.leonina.Mitochondrial paraphyly in eastern M.mulatta (with respect to M.cyclopis) and eastern M.assamensis (with respect to M.thibetana) were clearly observed in our study.In accordance with the results of Y chromosome,allozyme,nuclear genes and some morphological data (Delson,1980;Fooden & Lanyon,1989;Fooden,1990;Tosi et al,2000,2003a,b;Deinard & Smith,2001),our study on control region sequences supported M.arctoides to be classified into the sinica group.However,this result disagreed with the previous mtDNA studies (Hayasaka et al,1996;Morales & Melnick,1998;Tosi et al,2003a). 展开更多
关键词 MACACA MACAQUE Mitochondrial DNA control region PHYLOGENY
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Controlling Factors of Organic Nanopore Development: A Case Study on Marine Shale in the Middle and Upper Yangtze Region, South China 被引量:7
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作者 LIANG Feng ZHANG Qin +4 位作者 CUI Huiying MENG Qingqiang MA Chao LIANG Pingping GUO Wei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第4期1047-1059,共13页
The Upper Ordovician Wufeng-Lower Silurian Longmaxi and the Lower Cambrian Qiongzhusi shales are the major targets for shale gas exploration and development in China.Although the two organic-rich shales share similar ... The Upper Ordovician Wufeng-Lower Silurian Longmaxi and the Lower Cambrian Qiongzhusi shales are the major targets for shale gas exploration and development in China.Although the two organic-rich shales share similar distribution ranges and thicknesses,they exhibit substantially different exploration and development results.This work analyzed the nanopore structures of the shale reservoirs in this region.Pore development of 51 shale samples collected from various formations and locations was compared using the petromineralogical,geochemical,structural geological and reservoir geological methods.The results indicate that the reservoir space in these shales is dominated by organic pores and the total pore volume of micropores,mesopores,macropores in different tectonic areas and formations show different trends with the increase of TOC.It is suggested that organic pores of shale can be well preserved in areas with simple structure and suitable preservation conditions,and the shale with smaller maximum ancient burial depth and later hydrocarbongeneration-end-time is also more conducive to pore preservation.Organic pore evolution models are established,and they are as follows:①Organic matter pore development stage,②Early stage of organic matter pore destruction,and③late stage of organic matter pore destruction.The areas conducive to pore development are favorable for shale gas development.Research results can effectively guide the optimization and evaluation of favorable areas of shale gas. 展开更多
关键词 marine shale organic matter pores controlling factors pore evolution middle-upper Yangtze regions South China
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Control of Facies and Potential on Jurassic Hydrocarbon Accumulation and Prediction of Favorable Targets in the Hinterland Region of the Junggar Basin 被引量:7
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作者 CHEN Dongxia PANG Xiongqi +3 位作者 KUANG Jun KANG Dejiang LEI Lei DENG Yougen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1256-1272,共17页
Exploration practices show that the Jurassic System in the hinterland region of the Junggar Basin has a low degree of exploration but huge potential, however the oil/gas accumulation rule is very complicated, and it i... Exploration practices show that the Jurassic System in the hinterland region of the Junggar Basin has a low degree of exploration but huge potential, however the oil/gas accumulation rule is very complicated, and it is difficult to predict hydrocarbon-bearing properties. The research indicates that the oil and gas is controlled by structure facies belt and sedimentary system distribution macroscopically, and hydrocarbon-bearing properties of sand bodies are controlled by lithofacies and petrophysical facies microscopically. Controlled by ancient and current tectonic frameworks, most of the discovered oil and gas are distributed in the delta front sedimentary system of a palaeo-tectonic belt and an ancient slope belt. Subaqueous branch channels and estuary dams mainly with medium and fine sandstone are the main reservoirs and oil production layers, and sand bodies of high porosity and high permeability have good hydrocarbon-bearing properties; the facies controlling effect shows a reservoir controlling geologic model of relatively high porosity and permeability. The hydrocarbon distribution is also controlled by relatively low potential energy at the high points of local structure macroscopically, while most of the successful wells are distributed at the high points of local structure, and the hydrocarbon-bearing property is good at the place of relatively low potential energy; the hydrocarbon distribution is in close connection with faults, and the reservoirs near the fault in the region of relatively low pressure have good oil and gas shows; the distribution of lithologic reservoirs at the depression slope is controlled by the distribution of sand bodies at positions of relatively high porosity and permeability. The formation of the reservoir of the Jurassic in the Junggar Basin shows characteristics of favorable facies and low-potential coupling control, and among the currenffy discovered reservoirs and industrial hydrocarbon production wells, more than 90% are developed within the scope of facies- potential index FPI〉0.5, while the FPI and oil saturation of the discovered reservoir and unascertained traps have relatively good linear correlation. By establishing the relation model between hydrocarbon- bearing properties of traps and FPI, totally 43 favorable targets are predicted in four main target series of strata and mainly distributed in the Badaowan Formation and the Sangonghe Formation, and the most favorable targets include the north and east of the Shinan Sag, the middle and south of the Mobei Uplift, Cai-35 well area of the Cainan Oilfield, and North-74 well area of the Zhangbei fault-fold zone. 展开更多
关键词 JURASSIC facies control effect fluid potential prediction of hydrocarbon-bearing property hinterland region Junggar basin
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Pinning-controlled synchronization of complex networks with bounded or unbounded synchronized regions 被引量:5
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作者 邹艳丽 陈关荣 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3337-3346,共10页
This paper studies pinning-controlled synchronization of complex networks with bounded or unbounded synchronized regions. To study a state-feedback pinning-controlled network with N nodes, it first converts the contro... This paper studies pinning-controlled synchronization of complex networks with bounded or unbounded synchronized regions. To study a state-feedback pinning-controlled network with N nodes, it first converts the controlled network to an extended network of N+1 nodes without controls. It is shown that the controlled synchronizability of the given network is determined by the real part of the smallest nonzero eigenvalue of the coupling matrix of its extended network when the synchronized region is unbounded; but it is determined by the ratio of the real parts of the largest and the smallest nonzero eigenvalues of the coupling matrix when the synchronized region is bounded. Both theoretical analysis and numerical simulation show that the portion of controlled nodes has no critical values when the synchronized region is unbounded, but it has a critical value when the synchronized region is bounded. In the former case, therefore, it is possible to control the network to achieve synchronization by pinning only one node. In the latter case, the network can achieve controlled synchronization only when the portion of controlled nodes is larger than the critical value. 展开更多
关键词 SYNCHRONIZATION pinning control complex network synchronized region
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ON REGIONAL DIFFERENTIATION OF RIVER WATER ENVIRONMENT CAPACITY AND STRATEGIES TO CONTROL WATER ENVIRONMENT POLLUTION IN CHINA 被引量:4
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作者 王华东 王淑华 +1 位作者 鲍全盛 祁忠 《Chinese Geographical Science》 SCIE CSCD 1995年第2期116-124,共9页
China has large population and wide territory, the natural conditions of different regions are complicated. water resources are distributed unbalanced.economic developing states are unequal. For these reasons the vari... China has large population and wide territory, the natural conditions of different regions are complicated. water resources are distributed unbalanced.economic developing states are unequal. For these reasons the variation of concerned water environment capacity has obvious character of regional differentiation. In this paper, from the economic development point of view, the regular pattern of regional differentiation of China's water environment capacity resources is analyzed. the concept of contradictory degree between water environment capacity and economic development is introduced, based on them, rivers in China are divided into three regions, and corresponding strategies to control water pollution are advanced. The aims are to use river water environment capacity resources effectively. to control pollution and to improve environmental quality. 展开更多
关键词 WATER ENVIRONMENT capacity. regionAL differentiation. pollutioncontrol total quantity control
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Model Predictive Control of Nonlinear Systems: Stability Region and Feasible Initial Control 被引量:5
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作者 Xiao-Bing Hu Wen-Hua Chen 《International Journal of Automation and computing》 EI 2007年第2期195-202,共8页
This paper proposes a new method for model predictive control (MPC) of nonlinear systems to calculate stability region and feasible initial control profile/sequence, which are important to the implementations of MPC... This paper proposes a new method for model predictive control (MPC) of nonlinear systems to calculate stability region and feasible initial control profile/sequence, which are important to the implementations of MPC. Different from many existing methods, this paper distinguishes stability region from conservative terminal region. With global linearization, linear differential inclusion (LDI) and linear matrix inequality (LMI) techniques, a nonlinear system is transformed into a convex set of linear systems, and then the vertices of the set are used off-line to design the controller, to estimate stability region, and also to determine a feasible initial control profile/sequence. The advantages of the proposed method are demonstrated by simulation study. 展开更多
关键词 Model predictive control (MPC) stability region terminal region linear differential inclusion (LDI) linear matrix inequality (LMI).
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Role of 3'-untranslated region translational control in cancer development, diagnostics and treatment 被引量:6
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作者 Andrii Vislovukh Thaiz Rivera Vargas +1 位作者 Anna Polesskaya Irina Groisman 《World Journal of Biological Chemistry》 CAS 2014年第1期40-57,共18页
The messenger RNA 3'-untranslated region(3'UTR)plays an important role in regulation of gene expres-sion on the posttranscriptional level. The 3'UTR con-trols gene expression via orchestrated interactionbe... The messenger RNA 3'-untranslated region(3'UTR)plays an important role in regulation of gene expres-sion on the posttranscriptional level. The 3'UTR con-trols gene expression via orchestrated interactionbetween the structural components of mRNAs(cis-ele-ment) and the specific trans-acting factors(RNA bind-ing proteins and non-coding RNAs). The crosstalk ofthese factors is based on the binding sequences and/or direct protein-protein interaction, or just functionalinteraction. Much new evidence that has accumulatedsupports the idea that several RNA binding factors canbind to common mRNA targets: to the non-overlappingbinding sites or to common sites in a competitive fash-ion. Various factors capable of binding to the sameRNA can cooperate or be antagonistic in their actions.The outcome of the collective function of all factorsbound to the same mRNA 3'UTR depends on manycircumstances, such as their expression levels, affinity to the binding sites, and localization in the cell, which can be controlled by various physiological conditions. Moreover, the functional and/or physical interactions of the factors binding to 3'UTR can change the character of their actions. These interactions vary during the cell cycle and in response to changing physiological condi-tions. Abnormal functioning of the factors can lead to disease. In this review we will discuss how alterations of these factors or their interaction can affect cancer development and promote or enhance the malignant phenotype of cancer cells. Understanding these altera-tions and their impact on 3'UTR-directed posttran-scriptional gene regulation will uncover promising new targets for therapeutic intervention and diagnostics. We will also discuss emerging new tools in cancer di-agnostics and therapy based on 3'UTR binding factors and approaches to improve them. 展开更多
关键词 Translational control 3’ -untranslated region MICRORNAS RNA binding proteins CANCER
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Shallow Genetic Structure of Pholis fangi in Bohai Sea and Yellow Sea Inferred from mt DNA Control Region 被引量:2
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作者 GAO Tianxiang LI Lin +4 位作者 FANG Rundong LIU Guanghui WANG Lei XU Hanxiang SONG Na 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第4期947-952,共6页
Pholis fangi is an ecologically important fish species inhabiting Chinese coastal waters of Yellow Sea and Bohai Sea. To investigate the genetic diversity and population genetic structure of P. fangi, a fragment of 48... Pholis fangi is an ecologically important fish species inhabiting Chinese coastal waters of Yellow Sea and Bohai Sea. To investigate the genetic diversity and population genetic structure of P. fangi, a fragment of 487 bp in the first hypervariable region (HVR-1) of the mitochondrial DNA (mtDNA) control region was sequenced for 181 individuals collected from Bohai Sea and Yel- low Sea. A total of 18 polymorphic sites were detected, which defined 25 haplotypes. A moderate level of haplotype diversity (h = 0.7052) and a low level of nucleotide diversity (π= 0.0028) were detected. Both the phylogenetic tree and the haplotype network showed no significant genealogical structure difference among sampling locations. Pairwise FST comparison and hierarchical mo- lecular variance analysis (AMOVA) revealed that no significant genetic structure difference existed throughout the investigated re- gions, suggesting a high gene exchange among different populations. The results of neutrality test and mismatch distribution analysis indicated that a late Pleistocene population expansion (38000 127000 years ago) happened. Seasonal schooling migration may con- tribute to the genetically homogeneous population structure of the species. 展开更多
关键词 Pholis fangi control region of MTDNA GENETIC diversity GENETIC structure DEMOGRAPHIC history
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EVOLVEMENT AND CONTROL OF VULNERABLE ECOLOGICAL REGION—A Case Study in Ongniud Banner and Aohan Banner,Inner Mongolia 被引量:3
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作者 RANSheng-hong JINJian-jun 《Chinese Geographical Science》 SCIE CSCD 2004年第2期135-141,共7页
The evolvement of a vulnerable ecological region is a dynamic process, which is affected by various factors. During the evolvement process, human activities have a decisive effect. The purpose of studying vulnerable e... The evolvement of a vulnerable ecological region is a dynamic process, which is affected by various factors. During the evolvement process, human activities have a decisive effect. The purpose of studying vulnerable ecological region is to control human economic activities and to develop a negative feedback modulation mechanism.This paper established a model of vulnerable ecological region's evolvement by considering four synthetic variables.These synthetic variables are ecological carrying capacity, ecological resilience, economic development intensity, and economic development velocity. Finally, Ongniud Banner and Aohan Banner in North China were taken as study cases to simulate the evolvement processes of vulnerable ecological regions under different conditions of economic development. The results show that human activities have an important influence on the evolvement trend of vulnerable ecological region. 展开更多
关键词 vulnerable ecological region ecological evolvement ecological control SIMULATION Ongniud Banner Aohan Banner
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Broader pattern of tandem repeats in the mitochondrial control region of Perciformes 被引量:2
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作者 崔朝霞 刘媛 朱嘉濠 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期785-794,共10页
Perciformes,the largest order of vertebrates with 20 suborders,is the most diverse fish order that dominates vertebrate ocean life.The complete mitochondrial control region(CR) of Trichiurus japonicus(Trichiuridae,Sco... Perciformes,the largest order of vertebrates with 20 suborders,is the most diverse fish order that dominates vertebrate ocean life.The complete mitochondrial control region(CR) of Trichiurus japonicus(Trichiuridae,Scombroidei) and Pampus sp.(Stromateidae,Stromateoidei) were amplified and sequenced.Together with data from GenBank,the tandem repeats in the mitochondrial CR from 48 species,which covered nine suborders of Perciformes,are reported in this study.The tandem repeats tend to be long in the suborder Percoidei and Stromateoidei.The identical repeats in 21 species of Cichlidae suggest a common origin and have existed before species divergence.Larimichthys crocea shows tandem repeats instead of the typical structure of the central conserved sequence blocks,which was first reported in Perciformes and vertebrates.This might have resulted from interruption of the polymerase activity during the H-strand synthesis.The four broader patterns presented here for the tandem repeats,including those in both the 5' and 3' ends,only in the either 5' or 3' end,and in the central conserved domain of the control region,will be useful for understanding the evolution of species. 展开更多
关键词 MTDNA control region tandem repeats PERCIFORMES EVOLUTION
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Structure of Mitochondrial DNA Control Region of Pholis fangi and Its Phylogenetic Implication 被引量:2
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作者 LI Lin ZHANG Hui +1 位作者 SUN Dianrong GAO Tianxiang 《Journal of Ocean University of China》 SCIE CAS 2014年第3期491-496,共6页
In this study, the entire mitochondrial DNA(mtDNA) control region(CR) of Pholis fangi was amplified via polymerase chain reaction followed by direct sequencing. The length of the mtDNA CR consensus sequence of P. fang... In this study, the entire mitochondrial DNA(mtDNA) control region(CR) of Pholis fangi was amplified via polymerase chain reaction followed by direct sequencing. The length of the mtDNA CR consensus sequence of P. fangi was 853 bp in length. In accordance with the recognition sites as were previously reported in fish species, the mtDNA CR sequence of P. fangi can be divided into 3 domains, i.e., the extended terminal associated sequence(ETAS), the central conserved sequence block(CSB), and the CSB domain. In addition, the following structures were identified in the mtDNA CR sequence of P. fangi: 2 ETASs in the ETAS domain(TAS and cTAS), 6 CSBs in the central CSB domain(CSB-F to CSB-A), and 3 CSBs in the CSB domain(CSB-1 to CSB-3). These demonstrated that the structure of the mtDNA CR of P. fangi was substantially different from those of most other fish species. The mtDNA CR sequence of P. fangi contained one conserved region from 656 bp to 815 bp. Similar to most other fish species, P. fangi has no tandem repeat sequences in its mtDNA CR sequence. Phylogenetic analysis based on the complete mtDNA CR sequences showed that there were no genetic differences within P. fangi populations of the same geographical origin and between P. fangi populations of different geographical origins. 展开更多
关键词 Pholisfangi mitochondrial DNA control region STRUCTURE phylogenetic relationship
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Sexual Risk Behaviours among People Living with HIV and Implications for Control in the North West Region of Cameroon 被引量:3
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作者 Tebit Emmanuel Kwenti Dickson Shey Nsagha +1 位作者 Bita Dizzle Tayong Kwenti Anna Longdoh Njunda 《World Journal of AIDS》 2014年第2期198-205,共8页
In Cameroon, despite extensive control efforts against HIV/AIDS, the number of new HIV infections is still on the rise. The factors contributing to this are not clearly understood. We hypothesized that it may lie on p... In Cameroon, despite extensive control efforts against HIV/AIDS, the number of new HIV infections is still on the rise. The factors contributing to this are not clearly understood. We hypothesized that it may lie on people living with HIV (PLHIV). In a case-control descriptive study, we studied the characteristics and sexual risky behaviour of PLHIV in the North West Region of Cameroon which has the highest HIV prevalence. Participants were screened for HIV and a structured questionnaire was used in data collection. An equivalent number (350) of PLHIV and controls who did not differ with respect to age and sex participated. Relative to the control, PLHIV were generally less educated (P < 0.001), poorer and less privileged (P < 0.001) with no stable source of income. Among participants that were once married, a greater proportion of PLHIV were divorced (OR = 5.23, P = 0.007), and widows (OR = 2.73, P = 0.001). Among participants that were single, a relatively greater proportion of PLHIV practiced multi-partner sex (OR = 4.55, P< 0.001). History of STDs was higher in PLHIV than the control (OR = 1.88, P = 0.001). Out of 350 PLHIV, 280 (80%) admitted to having had sexual intercourse after being diagnosed of which only 127 (41.78%) admitted to using condoms and 132 (47.14%) admitted to concealing their HIV status from their sexual partner(s). These findings have implications in HIV control programs which should target the poor and the less educated, as well as the sexual behaviour of PLHIV, so as to reverse the current rising trend of new infections in the country. 展开更多
关键词 HIV/AIDS STDS Risk FACTORS HIV control NORTH WEST region Cameroon
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Risk prevention and control strategies for the severely affected areas of snow disaster in the Three Rivers Source Region(TRSR), China 被引量:1
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作者 ShiJin Wang ShengYun Chen YanQiang Wei 《Research in Cold and Arid Regions》 CSCD 2019年第3期248-252,共5页
Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter ... Historically,frequent and heavy snow disaster(SD)has caused serious livestock death and casualties,resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region(TRSR).From winter in 2018 to spring in 2019,the largest SD occurred in this area over the past 10 years,especially in core zones of the Lancang River Source Region.Field research results show that the main causes of the major SD include weak infrastructure(i.e.,roads,communications,warm sheds,and insufficient forage reserve),low rate of domestic animals for sale before the SD,and low loss settlement rate.SD occurrence could furtherly reduce the ability of disaster prevention,mitigation and relief of disaster loss.In the future,heavily affected SD areas should improve the forecasting ability of snowfall incidents,strengthen infrastructure construction,implement grass and livestock balance strategies,optimize livestock structure,improve loss settlement rate,and develop a modern compound model of animal husbandry development model that combines breeding,slaughtering and deep processing of animal product. 展开更多
关键词 THREE RIVERS Source region SNOW DISASTER severely AFFECTED area risk prevention control strategy
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LMI Approach to Robust H_∞/H_2 Controller Design with Regional Poles Constraint of a Pump-Motor System 被引量:1
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作者 郭初生 王向周 王渝 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期57-61,共5页
The time domain guideposts requirements of a pump-motor system is transfered into a series of constraints which express the robust performance upper bound and regional poles limits of the closed loop system. Then the ... The time domain guideposts requirements of a pump-motor system is transfered into a series of constraints which express the robust performance upper bound and regional poles limits of the closed loop system. Then the servo system control problem is transferred into the problem of robust performance optimizing under regional poles constrains described by linear matrix inequality (LMI). These LMIs are easy to solve through the Matlab LMI-toolbox. Simulations indicate that the controller has excellent dynamic, static and disturbance rejection performance, and the control system is robust and has perfect H2 performance to the bounded external torque disturbance. 展开更多
关键词 linear matrix inequality (LMI) H∞/H2 robust control regional poles placement pump-motor system servo system
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Lithostructural controls in Douala-Buea Region landscape (SW Cameroon margin):Insights from morphometric analysis 被引量:1
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作者 Christian BALLA ATEBA Sébastien OWONA +3 位作者 Moussa NSANGOU NGAPNA Véronique MANGA TSIMI DieudonnéMINYEM Joseph MVONDO ONDOA 《Journal of Mountain Science》 SCIE CSCD 2021年第1期68-87,共20页
The Douala-Buea Region(DBR;4°-5°N,9°-10°30’E),a portion of the southern Cameroon passive margin,developed on the Proterozoic granito-gneissic basement and the Cretaceous to Recent volcanosedimenta... The Douala-Buea Region(DBR;4°-5°N,9°-10°30’E),a portion of the southern Cameroon passive margin,developed on the Proterozoic granito-gneissic basement and the Cretaceous to Recent volcanosedimentary cover,was explored in order to evaluate the lithology and tectonics controls on its landscape usingthequalitativeandquantitative geomorphological analyses based on 30 m resolution Digital Elevation Models(DEM)and field evidences.This area displays an uneven and complex landscape differentiated into four morphological units:Douala,Nkondjock,Kumba and Buea Units.The Douala Unit corresponds to the Coastal Plain and is extended on the Douala-Kribi/Camposedimentarybasin.The Nkondjock Unit represents a middle plateau developed on a Proterozoic granito-gneissic basement.The Kumba Unit matches with the southernmost volcanic Western Cameroon High Plateau.The Buea Unit corresponds to the Mount Cameroon stratovolcano.The relief analysis through mountain-front sinuosity(Smf,1.19–1.43)and relative relief ratio(Rr,0.10–2.31)vary from one unit to another.The drainage network analysis including drainage patterns,stepped longitudinalriverprofiles,theassociated morphometric indexes,notably the concavity index(IC,0.56–0.88),deviation(D,267–2912 m),basin asymmetry factor(A_(F),6.37–42.12),hypsometric integral(HI,0.10–0.29),valley floor width to valley height ratio(V_(f),0.36–2.75),elongation ratio(R_(e),0.30–0.50),watershed slope(S,6.88–88.88)and stream length gradient index(SL,0–3332)vary from one basin to another too.These results also show the heterogeneous and uneven DBR landscape controlled by its lithology and active tectonics.The drainage system reveals concave to concavo-convex longitudinal river profile shapes with knick points,asymmetric basins,and fault reactivations,and highlights the tectonics activity that used to occur through the time and their control on the morphology.Together,they document the lithostructural controls on the DBR landscape evolution,extendable in the whole SW Cameroon margin. 展开更多
关键词 Morphometric indices Lithological control Structural control Morphological units Douala-Buea region SW Cameroon margin
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Mitochondrial DNA control region diversity and population structure of Pacific herring(Clupea pallasii)in the Yellow Sea and the Sea of Japan 被引量:1
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作者 刘名 高天翔 +5 位作者 樱井泰宪 贾宁 赵林林 杜晓 姜群 鹿志创 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期317-325,共9页
To investigate the genetic variation and population structure of Pacific herring in the Yellow Sea and the genetic differentiation between the Yellow Sea and the Sea of Japan, fragments of 479-bp mitochondrial DNA con... To investigate the genetic variation and population structure of Pacific herring in the Yellow Sea and the genetic differentiation between the Yellow Sea and the Sea of Japan, fragments of 479-bp mitochondrial DNA control region were sequenced for 110 individuals collected from three different periods in the Yellow Sea and one locality in the Sea of Japan. High haplotype diversity and moderate nucleotide diversity were observed in Pacific herring. AMOVA and exact test of population differentiation showed no significant genetic differentiations among the three populations of the Yellow Sea and suggested the populations can be treated as a single panmictic stock in the Yellow Sea. However, a large and significant genetic differentiation (ФST=0.11; P=0.00) was detected between the populations in the Yellow Sea and the Sea of Japan. The high sea water temperature in the Tsushima Strait was thought a barrier to block the gene exchange between populations of the two sea areas. The neutrality tests and mismatch distribution indicated recent population expansion in Pacific herring. 展开更多
关键词 Clupea pallasii mtDNA control region genetic diversity population genetics the YellowSea historical demography
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Study on regional stratagem for coal mine disasters control and prevention in China 被引量:1
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作者 SHEN Bao-hong LEI Yi 《Journal of Coal Science & Engineering(China)》 2009年第3期233-236,共4页
The regional strategy study was aimed at coal mine disaster control and prevention,which deepens and enriches the macro-strategy of coal mine disaster control andprevention,and provides an important support for the ra... The regional strategy study was aimed at coal mine disaster control and prevention,which deepens and enriches the macro-strategy of coal mine disaster control andprevention,and provides an important support for the rapid and healthy development ofthe regional coal industry.The country was divided into 4 regions:Northeast,North,Southand Xinqing.In view of the regional status of coal mine disasters,the regulation and developmenttrend of regional coal mine disasters were analyzed,the outstanding problemsand key factors were identified,and the general thoughts on regional coal mine disastercontrol and prevention were put forward. 展开更多
关键词 Coal mine disaster control and prevention regional strategy
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