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Fertility Values among Women of Childbearing Age in Hunan Province, China: A Cross-Sectional Study
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作者 Si Qin Jing Yue Yang Luo 《Advances in Reproductive Sciences》 2023年第3期60-71,共12页
Background: China is facing with a crisis of the aging population. After the implementation of the latest fertility policy, the research on fertility related issues is urgent. Objective: The objective of this study is... Background: China is facing with a crisis of the aging population. After the implementation of the latest fertility policy, the research on fertility related issues is urgent. Objective: The objective of this study is to explore the fertility values among women of childbearing age and the socio-demographic factors associated with it under the background of three-child policy, which is helpful to cope with the aging of the population. Methods: This study was conducted among 383 women of childbearing age who met the inclusion criteria using a general information questionnaire and the fertility values questionnaire from May to August 2021 in Hunan Province, China. Data were collected on the women’s socio-demographic characteristics and fertility values. The descriptive statistics, t-test and analysis of variance were used for data analysis. Results: The total mean score of the positive values was 43.55 ± 10.10, and that of the negative values was 50.87 ± 13.85. There were significant differences in the scores of the overall positive and negative values, as well as scores of each dimension (p The item mean score of the overall negative values (3.38 ± 0.93) was higher than that of the overall positive values (2.90 ± 0.67). Among the positive values, “emotional value” (4.26 ± 0.93) scored the highest, while “worrying about life changes” (3.88 ± 1.10) scored the highest among the negative values. There were significant differences in both the positive and negative values in terms of age, marital status, and “only-child” women or not (p Conclusion: The fertility values among women of childbearing age in Hunan Province were relatively negative, especially, excessive worries about life change since having a child, which may lead to further declines in fertility levels. Relevant support measures are urgently needed from the government to adapt to the three-child policy. 展开更多
关键词 Fertility values Positive values Negative values Three-Child Policy
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Spatial Interaction Between the Industrial Undertaking Capacity and Global Value Chain Position of East Asian Countries 被引量:3
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作者 ZHU Binbin CHI Fangyuan DU Lei 《Chinese Geographical Science》 SCIE CSCD 2021年第1期81-92,共12页
A comprehensive understanding of the spatial interaction between the industrial undertaking capability and the position of the global value chain of the 12 East Asian countries is conducive to strengthening regional c... A comprehensive understanding of the spatial interaction between the industrial undertaking capability and the position of the global value chain of the 12 East Asian countries is conducive to strengthening regional cooperation, gaining a say in foreign trade and becoming the dominant player in the global division of labor system. The article reveals the operating rules of the interaction between the industrial undertaking capacity and the global value chain position of East Asian countries by calculating the Global Moran Index(Moran’s I), coupling coordination degree and other indicators. The results show that: in time, the values of industrial undertaking capacity and the positions of global value chain in East Asian countries showed a sustained and stable growth trend, and have a consistent trend of change. Spatially, both of the two indexes had significant positive spatial correlation, with Moran’s I showing an ‘inverted U’pattern, and the spatial aggregation distribution of global value chain position lagged behind the spatial aggregation distribution of industrial undertaking capacity by one year. In terms of spatial coupling coordination, the coupling coordination values of the two indicators show a steady upward trend. Combined with the comparative advantage of each country, this paper provides suggestions for promoting the positions of Chinese and other East Asian industries in the global value chain from the perspectives of enhancing independent innovation capability and upgrading industrial structure. 展开更多
关键词 12 countries East Asian countries industry undertaking capability global value chain position spatial interaction
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SOME NECESSARY AND SUFFICIENT CONDITIONS FOR EXISTENCE OF POSITIVE SOLUTIONS FOR THIRD ORDER SINGULAR SUBLINEAR MULTI-POINT BOUNDARY VALUE PROBLEMS 被引量:5
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作者 韦忠礼 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1795-1810,共16页
We mainly study the existence of positive solutions for the following third order singular multi-point boundary value problem{x^(3)(t) + f(t, x(t), x′(t)) = 0, 0 〈 t 〈 1,x(0)-∑i=1^m1 αi x(ξi) = 0... We mainly study the existence of positive solutions for the following third order singular multi-point boundary value problem{x^(3)(t) + f(t, x(t), x′(t)) = 0, 0 〈 t 〈 1,x(0)-∑i=1^m1 αi x(ξi) = 0, x′(0)-∑i=1^m2 βi x′(ηi) = 0, x′(1)=0,where 0 ≤ ai≤∑i=1^m1 αi 〈 1, i = 1, 2, ···, m1, 0 〈 ξ1〈 ξ2〈 ··· 〈 ξm1〈 1, 0 ≤βj≤∑i^m2=1βi〈1,J=1,2, ···, m2, 0 〈 η1〈 η2〈 ··· 〈 ηm2〈 1. And we obtain some necessa βi 〈=11, j = 1,ry and sufficient conditions for the existence of C^1[0, 1] and C^2[0, 1] positive solutions by constructing lower and upper solutions and by using the comparison theorem. Our nonlinearity f(t, x, y)may be singular at x, y, t = 0 and/or t = 1. 展开更多
关键词 boundary value problems positive solutions lower and upper solutions comparison theorem
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POSITIVE SOLUTIONS FOR SOME 1-DIMENSIONAL BOUNDARY VALUE PROBLEMS OF LAPLACE-TYPE 被引量:1
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作者 Bai Zhanbing Liang Xiangqian Li Weiming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第1期13-20,共8页
This paper deals with the existence of triple positive solutions for the 1-dimensional equation of Laplace-type (φ(x′(t)))′+q(t)f(t,x(t),x′(t))=0,t∈(0,1),subject to the following boundary condit... This paper deals with the existence of triple positive solutions for the 1-dimensional equation of Laplace-type (φ(x′(t)))′+q(t)f(t,x(t),x′(t))=0,t∈(0,1),subject to the following boundary condition:a1φ(x(0))-a2φ(x'(0))=0,a3φ(x(1))+a4φ(x'(1))=0,where φ is an odd increasing homogeneous homeomorphism. By using a new fixed point theorem, sufficient conditions are obtained that guarantee the existence of at least three positive solu- tions. The emphasis here is that the nonlinear term f is involved with the first order derivative explicitly. 展开更多
关键词 triple positive solution equation of Laplace-type boundary value problem fixed point theorem.
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Theoretical Viewpoint on Value-increasing of Circular Economy——Study Based on the Practice of Circular Agriculture
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作者 Lizhi ZHU 《Asian Agricultural Research》 2017年第4期1-5,共5页
"3R" principle circular economy emphasizes the technical operation level,while the theoretical viewpoint on value-increasing of circular economy makes deep analysis based on environmental economics. The view... "3R" principle circular economy emphasizes the technical operation level,while the theoretical viewpoint on value-increasing of circular economy makes deep analysis based on environmental economics. The viewpoint takes for that the evaluation of any circular economic model should consider both the economic value and externalities. If the material units unattached to products in the economic system are circulated with value-increasing as more as possible,more value can be created with lower consumption of resources. The essential principle of circular economy is that the material units within an economic system should go through the multiple production to be circulated with value-increasing,the main purpose of circular economy is that the material units shouldn't attach to waste going out of the system as much as possible in order to reduce pollution emissions,the economic mechanism of circular economy is that the economic value chain should be used to pull the material units of the system to achieve smooth circulation. 展开更多
关键词 Circular value-increasing Material units Positive and negative value
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Evaluation of Sensitivity and Positive Predictive Values of Cytopathologic Diagnosis of Solid Masses in Dogs
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作者 Richard M. Kabuusu Tracy Volger +7 位作者 Sachin Kumthekar Keshaw Tiwari Alfred Chikweto Muhammad I. Bhaiyat Claude De Allie Ruth Alexander Carla Richards Ravindra N. Sharma 《Open Journal of Veterinary Medicine》 2016年第6期95-98,共4页
In this retrospective study, a total of 275 solid masses were examined for cytopathologic diagnosis. Twenty four percent (67/275) of these cytologic samples were followed by surgical biopsy and histopathologic diagnos... In this retrospective study, a total of 275 solid masses were examined for cytopathologic diagnosis. Twenty four percent (67/275) of these cytologic samples were followed by surgical biopsy and histopathologic diagnosis, allowing for comparisons. On average, the cutaneous and subcutaneous solid masses were recognized when the dogs were aged between 6 and 9 years old. The origins of the solid masses included connective tissue tumors 37.1% (23/62), epithelial tissue tumors 33.9% (21/62), round cell tumors 19.4% (12/62), masses of inflammatory lesions 4.8% (3/62) and lesions due to other causes 4.8% (3/62). The sensitivity and positive predictive value (PPV) of cytopathology in the diagnosis of solid masses were 93% (62/67) and 97% (62/64), respectively. Generally, neo-plasms were over diagnosed by cytopathology as was indicated by the positive predictive value. Both the sensitivity and the PPV of cytopathology comparative to histopathology in the diagnosis of inflammatory processes were 100% (3/3). The inflammatory lesions were eventually confirmed as necrotizing myositis, necro-suppurative cystitis and endocrine inflammatory dermatopathy based on histopathology. Less than 8% (5/67) of samples were incorrectly diagnosed by cytology. The study showed high accuracy between cytological and histopathological examination of solid masses in dogs, and thus a reliable diagnostic tool in patient care. 展开更多
关键词 CYTOPATHOLOGY HISTOPATHOLOGY DOG Sensitivity Positive Predictive value Solid Masses
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Diagnosis of Helicobacter pylori Infection in Low Out-Outcome Country: Rapid Urease Test, Serological Test, versus Direct Microbiological Examination with Gram Stain
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作者 Winnie Tatiana Bekolo Nga Guy Roger Nsenga Djapa +9 位作者 Kelly Ilinga Meme Mamende Antonin Wilson Ndjitoyap Ndam David Sepo Sepo Agnès Malongue Firmin Ankouane Andoulo Oudou Njoya Henry Luma Namme Elie Claude Ndjitoyap Ndam Carole Else Eboumbou Servais Albert Fiacre Eloumou Bagnaka 《Open Journal of Gastroenterology》 2023年第6期199-208,共10页
Introduction: Helicobacter pylori is a gram-negative bacillus responsible for numerous gastroduodenal pathologies, and this infection is a public health problem. The prevalence of infection with this bacterium remains... Introduction: Helicobacter pylori is a gram-negative bacillus responsible for numerous gastroduodenal pathologies, and this infection is a public health problem. The prevalence of infection with this bacterium remains high in countries with limited resources. Diagnosis relies mainly on numerous invasive and noninvasive methods. The aim of this work was to evaluate the different indirect diagnostic methods using bacterial cultures. Methods: We conducted a cross-sectional and analytical study from January to May 2022 in the gastroenterology departments of Douala General Hospital and Douala Military Hospital. All patients aged 18 years and older who were in the gastroenterology consultation and agreed to participate were included in our study. Sociodemographic, clinical, and paraclinical data were collected. Urease, liquid urea, and culture tests were performed from the specimens obtained by fibroscopy. Serological tests were performed on the blood sample. Results: 101 patients were included, 58 were female and 43 were male, for a sex ratio of 1.3. The mean age was 44.2 ± 16 years. The prevalence of infection was 90.5%, 44.1%, 40.6% and 21.8% for serology, direct microbiological examination, RUT (rapid urea test) and culture, respectively. Comparison of the different tests showed sensitivity and specificity of 67.1% and 64%, respectively, for RUT, 100% and 73.7%, respectively, for direct microbiological examination, and 100% and 14.8%, respectively, for serology. The positive and negative predictive values were 39.5% and 100% for serology, 39% and 85% for RUT, and 55.6% and 100% for direct microbiological examination, respectively. Conclusion: The prevalence of Helicobacter pylori infection depends on the type of test used. Direct examination is more reliable than RUT and serology. 展开更多
关键词 Helicobacter pylori Diagnostic Tests Sensitivity SPECIFICITY Positive and Negative Predictive value
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Remote interactions on two distributed quantum systems:nonlocal unambiguous quantum-state discrimination
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作者 陈立冰 金锐博 路洪 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期778-784,共7页
Remote quantum-state discrimination is a critical step for the implementation of quantum communication network and distributed quantum computation. We present a protocol for remotely implementing the unambiguous discr... Remote quantum-state discrimination is a critical step for the implementation of quantum communication network and distributed quantum computation. We present a protocol for remotely implementing the unambiguous discrimination between nonorthogonal states using quantum entanglements, local operations, and classical communications. This protocol consists of a remote generalized measurement described by a positive operator valued measurement (POVM). We explicitly construct the required remote POVM. The remote POVM can be realized by performing a nonlocal controlled-rotation operation on two spatially separated qubits, one is an ancillary qubit and the other is the qubit which is encoded by two nonorthogonal states to be distinguished, and a conventional local Von Neumann orthogonal measurement on the ancilla. The particular pair of states that can be remotely and unambiguously distinguished is specified by the state of the ancilla. The probability of successful discrimination is not optimal for all admissible pairs. However, for some subset it can be very close to an optimal value in an ordinary local POVM. 展开更多
关键词 remote quantum-state discrimination positive operator valued measure nonlocal controlled-rotation ENTANGLEMENT
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Teleporting a quantum controlled-Not with one target/two targets gate using two partially entangled states
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作者 陈立冰 金锐博 路洪 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期30-34,共5页
This paper considers the teleportation of quantum controlled-Not (CNOT) gate by using partially entangled states. Different from the known probability schemes, it presents a method for teleporting a CNOT gate with u... This paper considers the teleportation of quantum controlled-Not (CNOT) gate by using partially entangled states. Different from the known probability schemes, it presents a method for teleporting a CNOT gate with unit fidelity and unit probability by using two partially entangled pairs as quantum channel. The method is applicable to any two partially entangled pairs satisfying the condition that their smaller Schmidt coefficients μ and ν are (2μ + 2ν - 2μν - 1) ≥ 0. In this scheme, the sender's local generalized measurement described by a positive operator valued measurement (POVM) lies at the heart. It constructs the required POVM. It also puts forward a scheme for teleporting a CNOT with two targets gate with unit fidelity by using same quantum channel. With assistance of local operations and classical communications, three spatially separated users are able to complete the teleportation of a CNOT with two targets gate with probability of (2μ + 2ν - 1). With a proper value of μ and ν, the probability could reach nearly 1. 展开更多
关键词 partially entangled state TELEPORTATION CNOT gate positive operator valued measurement
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AMTS:Adaptive Multi-Objective Task Scheduling Strategy in Cloud Computing
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作者 HE Hua XU Guangquan +1 位作者 PANG Shanchen ZHAO Zenghua 《China Communications》 SCIE CSCD 2016年第4期162-171,共10页
Task scheduling in cloud computing environments is a multi-objective optimization problem, which is NP hard. It is also a challenging problem to find an appropriate trade-off among resource utilization, energy consump... Task scheduling in cloud computing environments is a multi-objective optimization problem, which is NP hard. It is also a challenging problem to find an appropriate trade-off among resource utilization, energy consumption and Quality of Service(QoS) requirements under the changing environment and diverse tasks. Considering both processing time and transmission time, a PSO-based Adaptive Multi-objective Task Scheduling(AMTS) Strategy is proposed in this paper. First, the task scheduling problem is formulated. Then, a task scheduling policy is advanced to get the optimal resource utilization, task completion time, average cost and average energy consumption. In order to maintain the particle diversity, the adaptive acceleration coefficient is adopted. Experimental results show that the improved PSO algorithm can obtain quasi-optimal solutions for the cloud task scheduling problem. 展开更多
关键词 quality of service cloud computing multi-objective task scheduling particle swarm optimization(PSO) small position value(SPV)
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Dynamical time versus system time in quantum mechanics
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作者 Duan Arsenovi Nikola Buri +1 位作者 Dragomir Davidovi Slobodan Prvanovi 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期101-107,共7页
Properties of an operator representing the dynamical time in the extended parameterization invariant formulation of quantum mechanics are studied. It is shown that this time operator is given by a positive operator me... Properties of an operator representing the dynamical time in the extended parameterization invariant formulation of quantum mechanics are studied. It is shown that this time operator is given by a positive operator measure analogously to the quantities that are known to represent various measurable time operators. The relation between the dynamical time of the extended formulation and the best known example of the system time operator, i.e., for the free one- dimensional particle, is obtained. 展开更多
关键词 time operators extended state space positive operator valued measure
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Predictive power of statistical significance
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作者 Thomas F Heston Jackson M King 《World Journal of Methodology》 2017年第4期112-116,共5页
A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fishe... A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fisher RA as a P-value of 0.05 or less. According to Fisher, any finding that is likely to occur by random variation no more than 1 in 20 times is considered significant. Neyman J and Pearson ES subsequently argued that Fisher's definition was incomplete. They proposed that statistical significance could only be determined by analyzing the chance of incorrectly considering a study finding was significant(a Type Ⅰ?error) or incorrectly considering a study finding was insignificant(a Type Ⅱ error). Their definition of statistical significance is also incomplete because the error rates are considered separately, not together. A better definition of statistical significance is the positive predictive value of a P-value, which is equal to the power divided by the sum of power and the P-value. This definition is more complete and relevant than Fisher's or Neyman-Peason's definitions, because it takes into account both concepts of statistical significance. Using this definition, a statistically significant finding requires a P-value of 0.05 or less when the power is at least 95%, and a P-value of 0.032 or less when the power is 60%. To achieve statistical significance, P-values must be adjusted downward as the study power decreases. 展开更多
关键词 Statistical significance Positive predictive value BIOSTATISTICS Clinical significance POWER
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Evaluation of the immunochromatographic strip test for the rapid diagnosis of antenatal syphilis in women in Eldoret,Kenya
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作者 Lydia B. Nyamwamu Michael M. Gicheru +3 位作者 Rekha R. Sharma lbert Kimutai Willy K.Tonui Peter Kamau Ngure 《Journal of Nanjing Medical University》 2009年第5期317-321,共5页
Objective: This study compared the performance of the immunochromatographic strip (ICS) to the Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum haemagglutination assay (TPHA) at a primary... Objective: This study compared the performance of the immunochromatographic strip (ICS) to the Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum haemagglutination assay (TPHA) at a primary health care setting. Methods: The study group was comprised of 150 females randomly drawn from a population of pregnant women attending their first antenatal visit or follow-up visits at West Maternity Hospital in Eldoret Kenya, but without a previous syphilis test during that pregnancy. On-site VDRL, ICS and TPHA tests were performed and immediate treatment provided where appropriate. The performance of the three tests was compared, Results: The sero-prevalence of syphilis as determined by the VDRL test was 3%. There was no significant difference between the ICS and the VDRL test (P 〉 0.05). The sensitivity and specificity of the ICS test were 80% and 98.6% respectively, while the negative predictive value (NPV) and positive predictive value (PPV) were both 100%. On the other hand, the sensitivity and specificity of the VDRL test were 66.7% and 99.3%, while the NPV and PPV were 80% and 98.6% respectively. The Treponema pallidum haemagglutination assay was used as a reference test and had sensitivity, specificity, NPV and PPV of 100%. Conclusion: The diagnostic accuracy of the ICS compared favorably with theVDRL gold standard. The use of the ICS in Kenya can improve the diagnosis of syphilis in health facilities both with and without laboratories and allow community health care workers to make a rapid diagnosis of the disease, and consequently make immediate therapeutic decisions. 展开更多
关键词 SYPHILIS Immunochromatographic strip test Venereal Disease Research Laboratory Treponema Pa//idum haemagglutinationAssay SPECIFICITY Sensitivity Positive Predictive value Negative Predictive value antenatal syphilis
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Feasibility of the Routine Clinical Use of a Multiplex Virus Polymerase Chain Reaction Assay Based on Blood Virus Detection in Hematopoietic Stem Cell-Transplanted Patients
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作者 Hiroko Tsunemine Miho Sasaki +9 位作者 Yuriko Zushi Toshiharu Saitoh Norio Shimizu Yasuhiro Tomaru Yumi Aoyama Ryusuke Yamamoto Tomomi Sakai Nobuyoshi Arima Taiichi Kodaka Takayuki Takahashi 《International Journal of Clinical Medicine》 2022年第2期67-81,共15页
Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. ... Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. In recent years, we developed a qualitative multiplex virus PCR assay capable of the simultaneous detection of 13 virus species within 3 h. However, because of the multiple and concomitant nature of this virus assay, it should be validated for qualitative reliability. Materials and Methods: As a preclinical examination, this multiplex PCR was able to detect 1.25 × 10<sup>3</sup> copies/mL of 13 synthesized virus genomes and preserved same virus DNAs by the serial dilution method. Blood samples from 40 patients who underwent hematopoietic stem cell transplantation were then examined by multiplex PCR for 13 virus species, followed by quantitative real-time PCR for all 13 virus species as reference PCR when these patients developed symptoms suggestive of viral infection. Results: In 421 cumulative qualitative-quantitative tests, the multiplex PCR certainly detected 1.0 × 103 copies/mL of 5 viruses (CMV, JCV, BKV, HHV-6, ADV) that were frequently detected and thus reasonably analyzed. The positive and negative predictive values of multiplex PCR were 84.2% - 93.3% and 90.7% - 99.0%, respectively, and sensitivity and specificity were 59.0% - 83.3% and 97.2% - 99.2%, respectively, for these 5 viruses. Conclusion: From these performances, the multiplex PCR assay may be acceptable in a routine clinical laboratory setting. 展开更多
关键词 Multiplex Virus PCR Assay Routine Laboratory Use Positive Predictive value Negative Predictive value Sensitivity SPECIFICITY
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Digital Trade Rules and the Position of Chinese Enterprises in the Global Value Chain
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作者 Yindan Wang Junjun Hou Zhenguo Wang 《China Finance and Economic Review》 2023年第3期106-128,共23页
Digital trade rules and higher positions of enterprises in the global value chain(GVC)are both important topics in the context of high-quality economic development.This paper refers to the data of RTA digital trade ru... Digital trade rules and higher positions of enterprises in the global value chain(GVC)are both important topics in the context of high-quality economic development.This paper refers to the data of RTA digital trade rules concluded by China in the TAPED database in 2000-2014 and the matched data in the WIOD database,the China Customs Import and Export Database and the China Industrial Enterprise Database to investigate the effects of digital trade rules on Chinese enterprises as to their ascending GVC positions.It finds that signing the RTA digital trade rules can steadily and significantly promote the position ascendance;compared with the digitalization rules on trading objects,signing the digitalization rules on trade modes produces greater effects of driving up the positions,which are realized mainly via the three channels of advancing cross-border flow of R&D factors,promoting corporate digital transformation,and improving professional management.Digital trade rules that are horizontally broader and vertically deeper are in greater favor of Chinese enterprises for ascending in the global value chain,which is especially evident among those in digital industry and processing trade.During the negotiations of digital trade rules,it's imperative to pay close attention to the rules on e-commerce cooperation,awareness of e-commerce importance,intellectual property protection,attempts in big data-related trade in goods,and cross-border data flow,so as to secure the core interests of Chinese enterprises in gaining higher positions.This paper offers great policy implications as to how to sign digital trade rules by China in the future and how to select partners in greater support for Chinese enterprises to ascend to the middle and high end of the global value chain. 展开更多
关键词 digital trade rules corporate position in the global value chain horizontal width vertical depth
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A NEW PLANAR BOOLEAN OPERATIO ALGORITHM BASED ON LINE SEGMENT SORTING
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作者 Ruibin Qu 《Computer Aided Drafting,Design and Manufacturing》 1995年第2期37-43,共4页
This paper presents a new method of Boolean operation First, a linesegment-polygonclassification theorem is proposed. Then, according to this theorem and basic idea for Booleanoperation, we give the discussion and app... This paper presents a new method of Boolean operation First, a linesegment-polygonclassification theorem is proposed. Then, according to this theorem and basic idea for Booleanoperation, we give the discussion and apposition of the new method. At last, a typical applicationis given. 展开更多
关键词 Boolean operation position value
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Human Capital Expansion and Global Value Chain Upgrading:Firm-level Evidence from China 被引量:4
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作者 Lamei Wu Guifu Chen Shuijun Peng 《China & World Economy》 2021年第5期28-56,共29页
Firms actively participate in the production of the global value chain(GVC),which is an important driving force for economic development.Using a difference-in-difference method,our research shows that industries that ... Firms actively participate in the production of the global value chain(GVC),which is an important driving force for economic development.Using a difference-in-difference method,our research shows that industries that are relatively more human-capital intensive experienced a larger GVC position upgrading after 2003 than they had in prior years.Second,mechanism analysis shows that human capital expansion increases firms’GVC position not only through an imported intermediate input effect but also through an innovation effect.Third,this study shows that increases in the college-educated labor force have a heterogeneous effect on a firm's GVC position across firms’various characteristics.Human capital expansion has the largest positive effect on state-owned firms relative to foreign and domestic private firms.Human capital expansion has also significantly improved the GVC position of firms located in China's eastern and central regions.The findings of this study indicate that it helps upgrading the GVC position of Chinese firms. 展开更多
关键词 global value chain position human capital expansion imported intermediate input effect innovation effect
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Existence of Three Positive Solutions for Some Second-Order M-Point Boundary Value Problems
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作者 Liu Yang Chun-fang Shen Xi-ping Liu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2008年第2期253-264,共12页
By using fixed-point theorems, some new results for multiplicity of positive solutions for some second order m-point boundary value problems are obtained.The associated Green's function of these problems are also given.
关键词 second order m-point boundary value problem positive solution cone fixed point
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Existence and Uniqueness of Positive Solutions to Sublinear-Linear Initial Value Problems
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作者 Yang Enhao Department of Mathematics Jinan University Guangzhou,510275 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1994年第1期19-29,共11页
Existence and uniqueness conditions for nonnegative solutions to initial value prob- lems of general sublinear-linear differential equations are obtained.They extend the uniqueness theorem due to H.Murakami~[6] and th... Existence and uniqueness conditions for nonnegative solutions to initial value prob- lems of general sublinear-linear differential equations are obtained.They extend the uniqueness theorem due to H.Murakami~[6] and the main results of H.G.Kaper and M.K.Kwong~[4]. 展开更多
关键词 Existence and Uniqueness of Positive Solutions to Sublinear-Linear Initial value Problems MATH
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ITERATIVE POSITIVE SOLUTIONS FOR SINGULAR RIEMANN-STIELTJES INTEGRAL BOUNDARY VALUE PROBLEM
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作者 Xiuli Lin Zengqin Zhao 《Annals of Applied Mathematics》 2016年第2期133-140,共8页
By applying iterative technique,we obtain the existence of positive solutions for a singular Riemann-Stieltjes integral boundary value problem in the case that f(t,u) is non-increasing respect to u.
关键词 Riemann-Stieltjes integral boundary value problems positive solution non-increasing iterative technique
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