In the reliability designing procedure of the vehicle components, when the distribution styles of the random variables are unknown or non-normal distribution, the result evaluated contains great error or even is wrong...In the reliability designing procedure of the vehicle components, when the distribution styles of the random variables are unknown or non-normal distribution, the result evaluated contains great error or even is wrong if the reliability value R is larger than 1 by using the existent method, in which case the formula is necessary to be revised. This is obviously inconvenient for programming. Combining reliability-based optimization theory, robust designing method and reliability based sensitivity analysis, a new method for reliability robust designing is proposed. Therefore the influence level of the designing parameters’ changing to the reliability of vehicle components can be obtained. The reliability sensitivity with respect to design parameters is viewed as a sub-objective function in the multi-objective optimization problem satisfying reliability constraints. Given the first four moments of basic random variables, a fourth-moment technique and the proposed optimization procedure can obtain reliability-based robust design of automobile components with non-normal distribution parameters accurately and quickly. By using the proposed method, the distribution style of the random parameters is relaxed. Therefore it is much closer to the actual reliability problems. The numerical examples indicate the following: (1) The reliability value obtained by the robust method proposed increases (】0.04%) comparing to the value obtained by the ordinary optimization algorithm; (2) The absolute value of reliability-based sensitivity decreases (】0.01%), and the robustness of the products’ quality is improved accordingly. Utilizing the reliability-based optimization and robust design method in the reliability designing procedure reduces the manufacture cost and provides the theoretical basis for the reliability and robust design of the vehicle components.展开更多
Traditional methods for early warning of dam displacements usually assume that residual displacements follow a normal distribution.This assumption deviates from the reality,thereby affecting the reliability of early w...Traditional methods for early warning of dam displacements usually assume that residual displacements follow a normal distribution.This assumption deviates from the reality,thereby affecting the reliability of early warning results and leading to misjudgments of dam displacement behavior.To solve this problem,this study proposed an early warning method using a non-normal distribution function.A new early warning index was developed using cumulative distribution function(CDF)values.The method of kernel density estimation was used to calculate the CDF values of residual displacements at a single point.The copula function was used to compute the CDF values of residual displacements at multiple points.Numerical results showed that,with residual displacements in a non-normal distribution,the early warning method proposed in this study accurately reflected the dam displacement behavior and effectively reduced the frequency of false alarms.This method is expected to aid in the safe operation of dams.展开更多
Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions hav...Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions have been widely investigated in [1-8]. The main ap- proach is to use the decomposition of polyanalytic functions and their generalization to transform the boundary value problems to their corresponding boundary value problems for analytic functions. Recently, inverse Riemann BVPs for generalized analytic functions or bianalytic functions have been investigated in [9-12]. In this paper, we consider a kind of Riemann BVP of non-normal type on the infinite straight line and discuss the solvable conditions and the general solution for it.展开更多
We will discuss the non-normal Hasemann boundary value problem: we may find these results are coincided with those of normal Hasemann boundary value problem and non-normal Riemann boundary value problem.
In this paper, we present and study a kind of Riemann boundary value problem of non-normal type for analytic functions on two parallel curves. Making use of the method of complex functions, we give the method for solv...In this paper, we present and study a kind of Riemann boundary value problem of non-normal type for analytic functions on two parallel curves. Making use of the method of complex functions, we give the method for solving this kind of doubly periodic Riemann boundary value problem of non-normal type and obtain the explicit expressions of solutions and the solvable conditions for it.展开更多
[Objectives]This study was conducted to explore rapid and large-scale screening and detection of peste des petits ruminants(PPR),so as to provide important technical means for prevention,control and purification of PP...[Objectives]This study was conducted to explore rapid and large-scale screening and detection of peste des petits ruminants(PPR),so as to provide important technical means for prevention,control and purification of PPR.[Methods]Soluble N protein and NH fusion protein were successfully obtained in an Escherichia coli expression system by optimizing E.coli codon and expression conditions.Furthermore,based on purified soluble N protein and NH fusion protein,a double-antigen sandwich time-resolved fluorescence immunoassay method for detection of peste des petits ruminants virus(PPRV)was established.[Results]The method has high sensitivity and specificity and can specifically detect the antibody against PPRV in sheep serum,and it has no cross reaction with other related diseases.The method was used to detect 292 clinical samples,and compared with French IDVET competition ELISA kit.The coincidence rates of positive samples and negative samples from the two kinds of test kits were 92.47%and 97.26%,respectively,and the overall coincidence rate was 94.86%.The intra-group and inter-group coefficients of variation in the repeatability test were less than 10%.[Conclusions]Compared with the traditional ELISA method,the double-antigen sandwich time-resolved fluorescence immunoassay for detection of PPRV has equivalent sensitivity and specificity,and simple and rapid operation,and thus high application and popularization value.展开更多
[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were ...[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value.展开更多
Peste ties petits ruminants is a kind of acute eontagious disease infecting goats anti sheep. In this study, antibtly monitoring and tracking of healthy goat and sheep immunized by peste des petits ruminants vaccine i...Peste ties petits ruminants is a kind of acute eontagious disease infecting goats anti sheep. In this study, antibtly monitoring and tracking of healthy goat and sheep immunized by peste des petits ruminants vaccine in Changping District of Beijing City were conducted, aiming at providing a reference for the devel- opment of effective immunization procedures.展开更多
Pourfour du petit综合征系因交感神经传导径路中,自下丘脑交感神经中枢往下至支配头颈上肢段任一部位刺激性病损所致。其临床表现与Horner征恰恰相反,表现为病变侧瞳孔散大、睑裂开大、眼球突出、头颈上肢或半身皮肤血管收缩以及出汗...Pourfour du petit综合征系因交感神经传导径路中,自下丘脑交感神经中枢往下至支配头颈上肢段任一部位刺激性病损所致。其临床表现与Horner征恰恰相反,表现为病变侧瞳孔散大、睑裂开大、眼球突出、头颈上肢或半身皮肤血管收缩以及出汗增多。展开更多
Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of P...Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of PPR disease in sheep and goats and its associated risk factors in Kassala State, Eastern Sudan. Across sectional study was conducted during the period from 30th August to 25th November 2015. The study was carried out using a structured questionnaire survey and a total of 918 blood samples were collected from apparently healthy unvaccinated sheep and goats in different localities in State of Kassala. A total of 546 sheep and 372 goats were tested for specific antibodies to nucleoprotein (NP) by competitive enzyme linked immunosorbent assay (cELISA). The apparent overall prevalence of PPR antibodies in Kassala was 58.2% while the true prevalence was calculated to be 61.3%. The apparent prevalence in sheep and goats was 68.1% and 43.5% respectively. Univariate analysis showed that the risk factors had significant associations with a cELISA positive status: locality, species, age, breed, husbandry system, housing mode, animals movement (p = 0.000) and animals sharing pasture and water (p = 0.003), while sex and newly introduced animals were not significant risk factors (p = 0.771) (p = 0.050) respectively. Factors found that significantly associated (p < 0.05) with increased odds of being cELISA positive in multivariate analysis were localities, species, age and newly introduced animals. The prevalence differed between localities and was the highest in the River Atbara (84.0%) locality, whereas it was lowest in Delta North (29.0%). No significant difference was observed among the sexes. However, the prevalence differed in different age groups and was 52.25% in animals of less than six months old;49.3% were between seven months and two years old and 65.5% were above two years old. In different husbandry systems, the prevalence was 47.9%, 73.0% and 49.2% in intensive, open grazing and pastoral systems respectively. Housing type effects were also observed;the highest prevalence was in animals housed in metal fence (83.3%). The movement pattern showed significant effect, where the prevalence was the highest (81.3%) in animals that move inter-states/inter-localities. It is concluded that the disease is endemic in Kassala State, high prevalent in sheep and goats, posing a threat to animal exportation, and may have a serious economic influence. Owners and herders should compulsorily vaccinate their animals yearly and animals should be investigated periodically for implementation of crucial eradication program.展开更多
In this paper, the existence of strictly positive solutions for N-species nonau- tonom ous Kolm ogorov com petition system s is studied. By applying the Schauder's fixed point theorem som e new sufficient condit...In this paper, the existence of strictly positive solutions for N-species nonau- tonom ous Kolm ogorov com petition system s is studied. By applying the Schauder's fixed point theorem som e new sufficient conditions are established. In particular, for the alm ost periodic system , the existence of strictly positive alm ostperiodic solutions is obtained. Som e previous results are im proved and generalized.展开更多
[ Objective] The paper was to get effective soluble N protein to establish indirect ELISA method for Peste des petits ruminants (PPR). [ Method] Soluble N protein with high expression was obtained from Escherichia c...[ Objective] The paper was to get effective soluble N protein to establish indirect ELISA method for Peste des petits ruminants (PPR). [ Method] Soluble N protein with high expression was obtained from Escherichia coli expression system through codon optimization and optimization of expression conditions, and indirect ELISA detection method based on N protein was further established. [ Result] The assay had no cross reaction with other sheep pathogens. The intra- and inter-batch variation coefficients were less than 9%, indicating the method had good repeatability. Furthermore, totally 480 clinical serum samples were detec- ted by the assay, and the agreement rate with commercial ELISA kit (IDVET) was 98.33%. [ Conclusion] The study laid a foundation for further development of mature PPRV antibody detection kits.展开更多
The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in Cameroon. A total of 269 herds randomly sa...The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in Cameroon. A total of 269 herds randomly sampled across the country have been studied and 1622 samples of serum have been levied on the sheep and goat. The c-ELISA has been studied in order to detect the presence of antibodies in small ruminants like an indicator of exposition to PPRV. The results revealed the circulation of PPRV in the country with a total sero-prevalence of 39% [95%CI;37 - 41] and a sero-prevalence of 63.2% [95%CI;57.2 - 69.2] at the herd level. Sero-prevalence was variable in the ten regions ranging from 7% [95% CI;6.2 - 8.4] to 73% [95% CI;62 - 84] with the northern zone (Adamawa, North and Far-North) having 52.3% [95% CI;37 - 60] and southern zone (including the remaining seven regions) recording 29% [95% CI;11 - 57]. Similarly, it was higher in animals found in urban/peri-urban areas than in rural areas with prevalence ratio of 2.9 [95% CI 2.54 - 3.4;p < 0.001] <em>i.e. </em>3 times more, 1.6 [95% CI 1.36 - 1.90;p < 0.001] <em>i.e.</em> 1.6 times more, and 5.02 [95% CI 3.91 - 6.85;p < 0.001] <em>i.e.</em> 5 times more at national level, in the northern zone and in the southern area, respectively. Five risk factors have been identified: the breeding environment, introduction of new animals into the herds, gathering of animals for pasture and watering, wandering and transhumance. The breeding area appeared to be the most important risk factor associated with disease exposure. The control measures for the eradication of this disease must take into account the epidemiological situation, the breeding environment, animal transhumance and breeding system.展开更多
Protective structures, built in the 1980's in order to reduce or stop coastal erosion in Rufisque, involved a modification of the coastal morpho-sedimentary landscape and have intensified the coastal dynamics. The di...Protective structures, built in the 1980's in order to reduce or stop coastal erosion in Rufisque, involved a modification of the coastal morpho-sedimentary landscape and have intensified the coastal dynamics. The diachronic study of beach profiles, before and after the seawalls construction showed that these protective structures accentuated the coastal erosion, with more important sedimentary deficits at the ends of the structures. Today, the Rufisque coast is characterized by a set of sedimentary cells whose morphological evolution and annual sedimentary dynamics are controlled by seasonal forcing: sedimentary deposits in dry season and erosion in wet season. However, this alternation of deposits and erosion phase shows spatiotemporal disparities. These disparities are very marked between a northwestern area characterized by concave profiles and a southeastern area (the bay of Rufisque) characterized by convex profiles and a much more important sedimentary deficit. The results also showed that these methods of shoreline protection are not durable measurements (degradation of the structures) and have exacerbated the vulnerability to coastal erosion as well as those of the coastal populations.展开更多
TWENTY one-year-old Fan Chunmei,a singer from an artensemble of the Chinese People‘s Liberation Army,won firstprize in the fourth Sound of Asia International Popular SongCompetition,held in Kazakhstan on July 19.Ai J...TWENTY one-year-old Fan Chunmei,a singer from an artensemble of the Chinese People‘s Liberation Army,won firstprize in the fourth Sound of Asia International Popular SongCompetition,held in Kazakhstan on July 19.Ai Jing,from LiaoningProvince,won the Alma-Ata Mayor’s Prize.She sang“My 1997.”Yuan Chenyie of the China Opera Theater took second prize inthe Classical division of the Tokyo International Vocal Music Com-petition,held in Tokyo in June this year.展开更多
This experiment was conducted to diagnose Peste des Petits Ruminants based on the eukaryotically-expressed PPRV nucleoprotein through an indirect ELISA. The full-length PPRV nucleoprotein gene was obtained from viral ...This experiment was conducted to diagnose Peste des Petits Ruminants based on the eukaryotically-expressed PPRV nucleoprotein through an indirect ELISA. The full-length PPRV nucleoprotein gene was obtained from viral genome RNA by RT-PCR. The amplified fragments were cloned into baculovirus donor vectors pFastHTA of the Bac-to-Bac system. These recombinant plasmids, pFastHTA-PPRV-N, were transformed into DH10Bac host bacteria to obtain recombinant shuttle plasmids, pBacmid-PPRV-N. Recombinant baculovirus, Bacmid-PPRV-N, was generated for expression of the PPRV nucleoprotein by transfecting recombinant pBacmid-PPRV-N with Lipofectamine 2000 into Sf21 insect cells. The efficient expression of PPRV Nucleoprotein by baculovirus in Sf21 cells was verified by SDS-PAGE and Western blot. An indirect ELISA was developed using recombinant PPRV nucleoprotein as the coating antigen. 37 goat sera from an epidemic area in Tibet and 92 goat sera from a non-infected area in Qinghai Province were simultaneously detected by the indirect ELISA, developed here, and the international standard cELISA kit. The sensitivity and specificity of the indirect ELISA was 100% and 96.2% compared with the cELISA kit. The coincidence rate of the two methods was 96.9%. The results demonstrated that the indirect ELISA established in this study works well for diagnosis of PPR.展开更多
基金supported by National Natural Science Foundation of China (Grant Nos. 51135003, U1234208, 51205050)New Teachers' Fund for Doctor Stations of Ministry of Education of China (Grant No.20110042120020)+1 种基金Fundamental Research Funds for the Central Universities, China (Grant No. N110303003)China Postdoctoral Science Foundation (Grant No. 2011M500564)
文摘In the reliability designing procedure of the vehicle components, when the distribution styles of the random variables are unknown or non-normal distribution, the result evaluated contains great error or even is wrong if the reliability value R is larger than 1 by using the existent method, in which case the formula is necessary to be revised. This is obviously inconvenient for programming. Combining reliability-based optimization theory, robust designing method and reliability based sensitivity analysis, a new method for reliability robust designing is proposed. Therefore the influence level of the designing parameters’ changing to the reliability of vehicle components can be obtained. The reliability sensitivity with respect to design parameters is viewed as a sub-objective function in the multi-objective optimization problem satisfying reliability constraints. Given the first four moments of basic random variables, a fourth-moment technique and the proposed optimization procedure can obtain reliability-based robust design of automobile components with non-normal distribution parameters accurately and quickly. By using the proposed method, the distribution style of the random parameters is relaxed. Therefore it is much closer to the actual reliability problems. The numerical examples indicate the following: (1) The reliability value obtained by the robust method proposed increases (】0.04%) comparing to the value obtained by the ordinary optimization algorithm; (2) The absolute value of reliability-based sensitivity decreases (】0.01%), and the robustness of the products’ quality is improved accordingly. Utilizing the reliability-based optimization and robust design method in the reliability designing procedure reduces the manufacture cost and provides the theoretical basis for the reliability and robust design of the vehicle components.
基金supported by the National Natural Science Foundation of China(Grant No.52109156)the Science and Technology Project of the Jiangxi Provincial Education Department(Grant No.GJJ190970).
文摘Traditional methods for early warning of dam displacements usually assume that residual displacements follow a normal distribution.This assumption deviates from the reality,thereby affecting the reliability of early warning results and leading to misjudgments of dam displacement behavior.To solve this problem,this study proposed an early warning method using a non-normal distribution function.A new early warning index was developed using cumulative distribution function(CDF)values.The method of kernel density estimation was used to calculate the CDF values of residual displacements at a single point.The copula function was used to compute the CDF values of residual displacements at multiple points.Numerical results showed that,with residual displacements in a non-normal distribution,the early warning method proposed in this study accurately reflected the dam displacement behavior and effectively reduced the frequency of false alarms.This method is expected to aid in the safe operation of dams.
文摘Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions have been widely investigated in [1-8]. The main ap- proach is to use the decomposition of polyanalytic functions and their generalization to transform the boundary value problems to their corresponding boundary value problems for analytic functions. Recently, inverse Riemann BVPs for generalized analytic functions or bianalytic functions have been investigated in [9-12]. In this paper, we consider a kind of Riemann BVP of non-normal type on the infinite straight line and discuss the solvable conditions and the general solution for it.
基金the National Natural Science Foundation of ChinaRF DP of Higher Education and SF of Wuhan Uni-versity(2 0 1990 3 3 6)
文摘We will discuss the non-normal Hasemann boundary value problem: we may find these results are coincided with those of normal Hasemann boundary value problem and non-normal Riemann boundary value problem.
文摘In this paper, we present and study a kind of Riemann boundary value problem of non-normal type for analytic functions on two parallel curves. Making use of the method of complex functions, we give the method for solving this kind of doubly periodic Riemann boundary value problem of non-normal type and obtain the explicit expressions of solutions and the solvable conditions for it.
基金Supported by National Key R&D Program for the Prevention and Control of Major Exotic Animal Diseases(2022YFD1800500)National Mutton Sheep Industrial Technology System(CARS39)+2 种基金Key Research and Development Program of Shandong Province(Major Science and Technology Innovation Project)(2021CXGC011306)Scientific Research Project of General Administration of Customs(2024HK033)Scientific Research Project of Jinan Customs(2023JK005).
文摘[Objectives]This study was conducted to explore rapid and large-scale screening and detection of peste des petits ruminants(PPR),so as to provide important technical means for prevention,control and purification of PPR.[Methods]Soluble N protein and NH fusion protein were successfully obtained in an Escherichia coli expression system by optimizing E.coli codon and expression conditions.Furthermore,based on purified soluble N protein and NH fusion protein,a double-antigen sandwich time-resolved fluorescence immunoassay method for detection of peste des petits ruminants virus(PPRV)was established.[Results]The method has high sensitivity and specificity and can specifically detect the antibody against PPRV in sheep serum,and it has no cross reaction with other related diseases.The method was used to detect 292 clinical samples,and compared with French IDVET competition ELISA kit.The coincidence rates of positive samples and negative samples from the two kinds of test kits were 92.47%and 97.26%,respectively,and the overall coincidence rate was 94.86%.The intra-group and inter-group coefficients of variation in the repeatability test were less than 10%.[Conclusions]Compared with the traditional ELISA method,the double-antigen sandwich time-resolved fluorescence immunoassay for detection of PPRV has equivalent sensitivity and specificity,and simple and rapid operation,and thus high application and popularization value.
基金Supported by The National Project for the Prevention and Control of Major Exotic Animal Diseases(2022YFD1800500)National Mutton Sheep Industrial Technology System(CARS39).
文摘[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value.
文摘Peste ties petits ruminants is a kind of acute eontagious disease infecting goats anti sheep. In this study, antibtly monitoring and tracking of healthy goat and sheep immunized by peste des petits ruminants vaccine in Changping District of Beijing City were conducted, aiming at providing a reference for the devel- opment of effective immunization procedures.
文摘Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of PPR disease in sheep and goats and its associated risk factors in Kassala State, Eastern Sudan. Across sectional study was conducted during the period from 30th August to 25th November 2015. The study was carried out using a structured questionnaire survey and a total of 918 blood samples were collected from apparently healthy unvaccinated sheep and goats in different localities in State of Kassala. A total of 546 sheep and 372 goats were tested for specific antibodies to nucleoprotein (NP) by competitive enzyme linked immunosorbent assay (cELISA). The apparent overall prevalence of PPR antibodies in Kassala was 58.2% while the true prevalence was calculated to be 61.3%. The apparent prevalence in sheep and goats was 68.1% and 43.5% respectively. Univariate analysis showed that the risk factors had significant associations with a cELISA positive status: locality, species, age, breed, husbandry system, housing mode, animals movement (p = 0.000) and animals sharing pasture and water (p = 0.003), while sex and newly introduced animals were not significant risk factors (p = 0.771) (p = 0.050) respectively. Factors found that significantly associated (p < 0.05) with increased odds of being cELISA positive in multivariate analysis were localities, species, age and newly introduced animals. The prevalence differed between localities and was the highest in the River Atbara (84.0%) locality, whereas it was lowest in Delta North (29.0%). No significant difference was observed among the sexes. However, the prevalence differed in different age groups and was 52.25% in animals of less than six months old;49.3% were between seven months and two years old and 65.5% were above two years old. In different husbandry systems, the prevalence was 47.9%, 73.0% and 49.2% in intensive, open grazing and pastoral systems respectively. Housing type effects were also observed;the highest prevalence was in animals housed in metal fence (83.3%). The movement pattern showed significant effect, where the prevalence was the highest (81.3%) in animals that move inter-states/inter-localities. It is concluded that the disease is endemic in Kassala State, high prevalent in sheep and goats, posing a threat to animal exportation, and may have a serious economic influence. Owners and herders should compulsorily vaccinate their animals yearly and animals should be investigated periodically for implementation of crucial eradication program.
文摘In this paper, the existence of strictly positive solutions for N-species nonau- tonom ous Kolm ogorov com petition system s is studied. By applying the Schauder's fixed point theorem som e new sufficient conditions are established. In particular, for the alm ost periodic system , the existence of strictly positive alm ostperiodic solutions is obtained. Som e previous results are im proved and generalized.
基金Supported by New Diagnosis and Detection Technology Research for Major Animal Diseases in Cattle and Sheep(No.2016YFD0500901)
文摘[ Objective] The paper was to get effective soluble N protein to establish indirect ELISA method for Peste des petits ruminants (PPR). [ Method] Soluble N protein with high expression was obtained from Escherichia coli expression system through codon optimization and optimization of expression conditions, and indirect ELISA detection method based on N protein was further established. [ Result] The assay had no cross reaction with other sheep pathogens. The intra- and inter-batch variation coefficients were less than 9%, indicating the method had good repeatability. Furthermore, totally 480 clinical serum samples were detec- ted by the assay, and the agreement rate with commercial ELISA kit (IDVET) was 98.33%. [ Conclusion] The study laid a foundation for further development of mature PPRV antibody detection kits.
文摘The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in Cameroon. A total of 269 herds randomly sampled across the country have been studied and 1622 samples of serum have been levied on the sheep and goat. The c-ELISA has been studied in order to detect the presence of antibodies in small ruminants like an indicator of exposition to PPRV. The results revealed the circulation of PPRV in the country with a total sero-prevalence of 39% [95%CI;37 - 41] and a sero-prevalence of 63.2% [95%CI;57.2 - 69.2] at the herd level. Sero-prevalence was variable in the ten regions ranging from 7% [95% CI;6.2 - 8.4] to 73% [95% CI;62 - 84] with the northern zone (Adamawa, North and Far-North) having 52.3% [95% CI;37 - 60] and southern zone (including the remaining seven regions) recording 29% [95% CI;11 - 57]. Similarly, it was higher in animals found in urban/peri-urban areas than in rural areas with prevalence ratio of 2.9 [95% CI 2.54 - 3.4;p < 0.001] <em>i.e. </em>3 times more, 1.6 [95% CI 1.36 - 1.90;p < 0.001] <em>i.e.</em> 1.6 times more, and 5.02 [95% CI 3.91 - 6.85;p < 0.001] <em>i.e.</em> 5 times more at national level, in the northern zone and in the southern area, respectively. Five risk factors have been identified: the breeding environment, introduction of new animals into the herds, gathering of animals for pasture and watering, wandering and transhumance. The breeding area appeared to be the most important risk factor associated with disease exposure. The control measures for the eradication of this disease must take into account the epidemiological situation, the breeding environment, animal transhumance and breeding system.
文摘Protective structures, built in the 1980's in order to reduce or stop coastal erosion in Rufisque, involved a modification of the coastal morpho-sedimentary landscape and have intensified the coastal dynamics. The diachronic study of beach profiles, before and after the seawalls construction showed that these protective structures accentuated the coastal erosion, with more important sedimentary deficits at the ends of the structures. Today, the Rufisque coast is characterized by a set of sedimentary cells whose morphological evolution and annual sedimentary dynamics are controlled by seasonal forcing: sedimentary deposits in dry season and erosion in wet season. However, this alternation of deposits and erosion phase shows spatiotemporal disparities. These disparities are very marked between a northwestern area characterized by concave profiles and a southeastern area (the bay of Rufisque) characterized by convex profiles and a much more important sedimentary deficit. The results also showed that these methods of shoreline protection are not durable measurements (degradation of the structures) and have exacerbated the vulnerability to coastal erosion as well as those of the coastal populations.
文摘TWENTY one-year-old Fan Chunmei,a singer from an artensemble of the Chinese People‘s Liberation Army,won firstprize in the fourth Sound of Asia International Popular SongCompetition,held in Kazakhstan on July 19.Ai Jing,from LiaoningProvince,won the Alma-Ata Mayor’s Prize.She sang“My 1997.”Yuan Chenyie of the China Opera Theater took second prize inthe Classical division of the Tokyo International Vocal Music Com-petition,held in Tokyo in June this year.
文摘This experiment was conducted to diagnose Peste des Petits Ruminants based on the eukaryotically-expressed PPRV nucleoprotein through an indirect ELISA. The full-length PPRV nucleoprotein gene was obtained from viral genome RNA by RT-PCR. The amplified fragments were cloned into baculovirus donor vectors pFastHTA of the Bac-to-Bac system. These recombinant plasmids, pFastHTA-PPRV-N, were transformed into DH10Bac host bacteria to obtain recombinant shuttle plasmids, pBacmid-PPRV-N. Recombinant baculovirus, Bacmid-PPRV-N, was generated for expression of the PPRV nucleoprotein by transfecting recombinant pBacmid-PPRV-N with Lipofectamine 2000 into Sf21 insect cells. The efficient expression of PPRV Nucleoprotein by baculovirus in Sf21 cells was verified by SDS-PAGE and Western blot. An indirect ELISA was developed using recombinant PPRV nucleoprotein as the coating antigen. 37 goat sera from an epidemic area in Tibet and 92 goat sera from a non-infected area in Qinghai Province were simultaneously detected by the indirect ELISA, developed here, and the international standard cELISA kit. The sensitivity and specificity of the indirect ELISA was 100% and 96.2% compared with the cELISA kit. The coincidence rate of the two methods was 96.9%. The results demonstrated that the indirect ELISA established in this study works well for diagnosis of PPR.