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
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
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
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
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
"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
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
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
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
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
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
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
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
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
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.
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
In this paper, we are concerned with the symmetric positive solutions of a 2n-order boundary value problems on time scales. By using induction principle,the symmetric form of the Green＇s function is established. In o...In this paper, we are concerned with the symmetric positive solutions of a 2n-order boundary value problems on time scales. By using induction principle,the symmetric form of the Green＇s function is established. In order to construct a necessary and sufficient condition for the existence result, the method of iterative technique will be used. As an application, an example is given to illustrate our main result.展开更多
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.
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
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
文摘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.
基金supported by the National Science Foundation of Shandong Province(ZR2009AM004)
文摘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.
基金Supported by the NNSF of China(10371006) Tianyuan Youth Grant of China(10626033).
文摘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.
文摘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.
基金Under the auspices of China’s National Social Science Research Grant(No.16BTJ025)。
文摘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.
文摘"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.
文摘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.
基金partially been sponsored by the National Science Foundation of China(No.61572355,61272093,610172063)Tianjin Research Program of Application Foundation and Advanced Technology under grant No.15JCYBJC15700
文摘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.
基金Project supported by the Natural Science Foundation of Guangdong Province,China (Grant No 06029431)
文摘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.
基金Project supported by the Natural Science Foundation of Guangdong Province,China(Grant Nos06029431and020127)the Natural Science Foundation of the Education Bureau of Guangdong Province,China(Grant No Z02069)
文摘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.
基金Project supported by the Ministry of Science and Education of the Republic of Serbia (Grant Nos. 171017, 171028, and 171006)
文摘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.
文摘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.
文摘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.
文摘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].
基金the Natural Science Foundation of Anhui Educational Department(Kj2007b055) Youth Project Foundation of Anhui Educational Department(2007jqL101,2007jqL102)
文摘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.
文摘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.
基金Supported by NNSF of China(11201213,11371183)NSF of Shandong Province(ZR2010AM022,ZR2013AM004)+2 种基金the Project of Shandong Provincial Higher Educational Science and Technology(J15LI07)the Project of Ludong University High-Quality Curriculum(20130345)the Teaching Reform Project of Ludong University in 2014(20140405)
文摘In this paper, we are concerned with the symmetric positive solutions of a 2n-order boundary value problems on time scales. By using induction principle,the symmetric form of the Green＇s function is established. In order to construct a necessary and sufficient condition for the existence result, the method of iterative technique will be used. As an application, an example is given to illustrate our main result.
基金supported by Program for Scientific research innovation team in Colleges and universities of Shandong Provincethe Doctoral Program Foundation of Education Ministry of China(20133705110003)+1 种基金the Natural Science Foundation of Shandong Province of China(ZR2014AM007)the National Natural Science Foundation of China(11571197)
文摘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.
基金Major Project of National Social Science Fund of China"Research on China's Standards Governance and Reconstruction of Global Trade Rules"(17ZDA099)Youth Project of National Natural Science Foundation of China"Research on the Division of Labor Pattern,Functional Upgrading Effect,and Policy Optimization of China's Embedding into the Global Value Chain"(72203058).
文摘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.
文摘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.
