This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global s...This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global statistics of TB occurrence, it is evident that the national incidence of TB has reduced from 10.55 per 100,000 in 2015 to 8.36 per 100,000 in 2019;despite this, there are still some difficulties because migrants bring new strains of Mycobacterium tuberculosis. Hindrances, including language barriers and perceived immigration status, hinder patients from seeking medical attention or doctors from diagnosing diseases. Each patient and each cultural group need special attention to public health, enhancing living circumstances, and health care support. Community participation, inclusion of TB control programs into functional healthcare facilities, and the functioning of TB programs need to be stressed to address TB issues. Considering the focus on social, economic, and cultural approaches, the country can make severe advancements in TB control and population protection. This holistic analysis is critical for a long-term effective strategy to combat TB in the Kingdom.展开更多
Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example t...Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.展开更多
Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and...Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and control,agricultural prevention and control,physical prevention and control,chemical prevention and control,and biological prevention and control can effectively control the damage of S.frugiperda and guarantee the safety of food production.The results will provide some reference for the prevention and control of S.frugiperda.展开更多
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r...Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology.展开更多
Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,s...Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,sharp decrease of global forest areas,soil erosion,acid rain pollution,water pollution and so on.This essay is to introduce the present status,formation causes and hazardous condition of acid rain pollution in china.Some feasible and effective control measures are put forward according to the actual situation in China.展开更多
The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and ac...The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and actively carrying out comprehensive management to control the pests damage in the economic permissible level.展开更多
[Objective] This study aimed to find out effective measures to solve land- scape water eutrophication. [Method] Based on an overview of the urban landscape water characteristics and pollution control situation, taking...[Objective] This study aimed to find out effective measures to solve land- scape water eutrophication. [Method] Based on an overview of the urban landscape water characteristics and pollution control situation, taking an example of the artificial lakes in a campus in Xi'an, we comparatively analyzed the present pollution situation of Xiuyuan Lake and Mingyuan Lake, and provided controlling measures against eutrophication pollution, as well as restoration measures. [Result] All the indicators (TN, TP, Chl-a, NH3-N, CODMn) of the landscape water quality in both Xiuyuan Lake and Mingyuan Lake went severely beyond the Grade IV standards, presenting a state of heavy eutrophication. Nitrogen, phosphorus and other nutrient salts carried by atmospheric precipitation and its runoff, as well as domestic garbage generated by human activities were primary exogenous pollutants of the artificial lakes. And the release of sediment pollutants was endogenous substances causing deterioration of water quality. [Conclusion] This paper presents some measures to control the pollution of artificial lakes, and provides scientific references for the construction, operation and management of artificial lakes, as well as maintenance of aquatic environment.展开更多
[Objective] The aim was to investigate pesticide use in Qujing city and explore the control measures.[Method] Surveys were made on pesticide use by farmers in five vegetable bases in Qujing city by questionnaires to s...[Objective] The aim was to investigate pesticide use in Qujing city and explore the control measures.[Method] Surveys were made on pesticide use by farmers in five vegetable bases in Qujing city by questionnaires to study pesticide use and existing problems by farmers.[Result] Some problems existed in pesticide use in Qujing,such as non-standard pesticide source,lower-recognition of pesticide and impacts of pesticide residues on environment,and without professional guidance.[Conclusion] The existing problems can be resolved by enhancing technical trainings of technicians or pesticide managers,strengthening pesticide promotion,and reinforcing examination of pesticide residues.展开更多
In the article, status quo of oil pollution in China's offshore area was in- troduced, and the sources of oil pollution in the ocean were analyzed. Furthermore, the possible hazards of marine oil pollution were discu...In the article, status quo of oil pollution in China's offshore area was in- troduced, and the sources of oil pollution in the ocean were analyzed. Furthermore, the possible hazards of marine oil pollution were discussed and related countermea- sures were proposed, including implementation of laws and regulations, enhancing awareness of environment protection, improvement of pollution monitoring and early warning mechanism, physical treatment, chemical treatment and biological treatment. With economy development, the demand of oil is increasing accordingly. Hence, oil pollution has become an urgent issue to be solved for better exploration of oil and protection of marine environment.展开更多
Background:To analyze the epidemiological characteristics of varicella epidemics in Chongqing Municipality from 2014 to 2021,and to provide a scientific basis for the formulation of varicella prevention and control me...Background:To analyze the epidemiological characteristics of varicella epidemics in Chongqing Municipality from 2014 to 2021,and to provide a scientific basis for the formulation of varicella prevention and control measures.Methods:Data on the incidence of varicella outbreaks and vaccination data in Chongqing from 2014 to 2021 were collected through the China Disease Control and Prevention Information System and statistically analyzed using descriptive epidemiological methods.Results:From 2014 to 2021,213,715 cases of varicella were reported in Chongqing Municipality,with an average annual incidence rate of 86.26/100,000,with a statistically significant difference(χ^(2)=24,972.069,P<0.001);varicella incidence is seasonal,with peaks in May/June and October/December each year,presenting a“double-peak distribution”.The average annual incidence rate of varicella in municipal districts was 90.74/100,000,which was higher than that of counties 69.62/100,000 and autonomous counties 84.04/100,000;the average annual incidence rate of varicella in males was 89.37/100,000,and in females,82.22/100,000,with the difference not being statistically significant;the age of onset of the disease was mainly in the group of people under 15 years of age,with a total of 190,021 cases reported(88.9%),with 5-9 years old(35.7%)as the high incidence age group.The incidence occupation was dominated by students in 133,733 cases(62.6%).Conclusion:The overall varicella epidemic in Chongqing is on the rise,and has obvious seasonal,regional and population distribution characteristics.The prevention and control of varicella epidemic should be strengthened,the publicity of varicella vaccine should be increased,and it is recommended that varicella vaccine should be included in the national immunization program.展开更多
Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklima...Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the''Dead Sea''due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts.展开更多
Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in W...Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in Western China.This study aimed to evaluate the strategy of hepatitis B prevention and control in Western China and identify potential areas and strategies for improvement.Methods Susceptible population vaccination,health education,professional training of doctors,and other prevention and control measures have been implemented in Wuwei city since 2010.Data were obtained from three representative cross-sectional serosurveys conducted in 2010,2013,and 2015.The serum samples were subjected to enzyme-linked immunosorbent assays to detect the following seromarkers:HBV surface antigen(HBsAg),antibody against hepatitis B surface antigen(anti-HBs),and antibody against hepatitis B core antigen(anti-HBc).Estimates of variance were determined using Taylor series linearization methods.Results The three serosurveys revealed decreases in the prevalence of HBsAg(7.19% in 2010 vs.6.51% in 2013 vs.5.87% in 2015)and anti-HBc positivity(43.89%vs.32.87%vs.28.46%)and an increase in the prevalence of anti-HBs positivity(49.07%vs.53.66%vs.53.72%)over time.From 2010 to 2015,the legally reported incidence of hepatitis B in Wuwei city decreased from 686.53/100,000 to 53.72/100,000.Notably,persistently high HBsAg-positive rates(above 5.40%)were observed among subjects aged 20–69 years old in the three serosurveys;the prevalence of HBsAg was above 1% among children younger than 10 years old.Furthermore,rural subjects had higher rates of HBsAg and anti-HBc positivity than their urban counterparts(6.04%vs.4.83% and 30.26%vs.20.35%,respectively)in 2015 but had a lower rate of anti-HBs positivity(49.68 vs.55.18%).Multivariate regression analysis showed that age,urban and rural areas,and education level were the main factors affecting HBV infection.Conclusion Although vaccine-based prevention and control measures reduced the rate of HBV infection in Wuwei City over time,the hepatitis B infection rate in children younger than 10 years was still higher than the national average level.Therefore,the prevention and control of mother-to-child transmission and the management of the infected should be the focus of future prevention and control work.展开更多
BACKGROUND: Hemodialysis (HD) patients are at high risk of infection by hepatitis B virus (HBV) or hepatitis C virus (HCV). The present study was designed to determine the impact of quality control measures on the pre...BACKGROUND: Hemodialysis (HD) patients are at high risk of infection by hepatitis B virus (HBV) or hepatitis C virus (HCV). The present study was designed to determine the impact of quality control measures on the prevention of transmission of blood-borne viruses. METHODS: A total of 6182 adult maintenance HD patients from all HD units in Zhejiang Province were recruited on January 1, 2007. The baseline demographic and clinical characteristics were recorded and all patients were followed up until death or survival at 4 years later. The Quality Control Standards of Hemodialysis were gradually implemented in HD units. The HBV or HCV seroconversion rates of the recruited patients were calculated and compared every year during the observation period. RESULTS: The prevalence of HBV was 8.3% at the beginning of the study, and 6.6% for HCV. With the implementation of the HD quality control measures, the HBV seroconversion rate tended to decrease year by year (χ 2 =6.620, P=0.085), and the HCV seroconversion rate decreased significantly (χ 2 =10.41, P=0.015). Compared with the data in 2007, the HBV seroconversion rate (χ 2 =4.204, P=0.040, relative risk ratio 0.393, 95% CI 0.156-0.991) and the HCV seroconversion rate (χ 2 =7.373, P=0.007, relative risk ratio 0.386, 95% CI 0.189-0.787) decreased significantly in 2010. CONCLUSION: Quality control measures for HD decreased the seroconversion rates of HBV or HCV in HD patients, showing that updated quality control measures reduce the risk for transmission of blood-borne viruses in the HD population.展开更多
[Objective] The aim was to analyze the current status and control measures of ecological restoration in Karst rocky desertification area of Guizhou.[Method] The current status and existing problems of ecological resto...[Objective] The aim was to analyze the current status and control measures of ecological restoration in Karst rocky desertification area of Guizhou.[Method] The current status and existing problems of ecological restoration in Karst rocky desertification area of Guizhou were studied firstly,and main control measures were put forward according to existing problems.[Result] At present,Karst rocky desertification area in Guizhou has suitable ecological environment,obvious control results and rich control experience,and there exist many problems like ambiguous concept of ecological restoration,biased control emphasis,single control measure and serious water shortage due to lagging engineering construction.Control measures mainly include combining natural restoration with artificial tending to speed up ecological restoration,reinforcing the restoration and rebuilding of development and construction project to prevent the deterioration of regional ecological environment,speeding up the construction of environmental friendly energy infrastructures to decrease the damage of vegetation by human activities,increasing industrial structure adjustment and greatly developing green industry and improving the investment in technological innovation to promote the rapid development of ecological restoration.[Conclusion] The study could provide scientific references for the ecological restoration in other Karst rocky desertification area in Southwest China.展开更多
According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and devel...According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and development of soil and water loss is analyzed. The conclusion is that: (1) generally, the situation of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is light, however, soil and water loss in some regions is serious, especially in the middle reach area of the river; (2) soil and water loss in the Lancang River Mekong River (in Yunnan section, China) watershed presents developing tendency and it is mainly caused by human beings. In accordance with these results, the control measures for soil and water loss are discussed.展开更多
Environmental pollution problem generated in dairy farming process is the bottleneck restricting development of animal husbandry. By using the investigation data from dairy farmers of Inner Mongolia,environmental poll...Environmental pollution problem generated in dairy farming process is the bottleneck restricting development of animal husbandry. By using the investigation data from dairy farmers of Inner Mongolia,environmental pollution problem generated by dairy farming in Inner Mongolia and its cause were analyzed,and prevention and control measures were put forward. The research result showed that weak technology support of environmental treatment and environmental-protection awareness of dairy farmer and bad application effect of pollution control technology caused by lower education degree of dairy farmer were main reasons for environmental pollution problem. We should develop dairy circular economy,advocate a moderate scale,scientifically breed,and enhance training of pollution control technology and propaganda to protect environment.展开更多
Soil pollution has been considered as one of the main environmental problems in the world nowadays. The source of soil heavy metal pollution in farmland, the effect of heavy metal pollution on soil quality in farmland...Soil pollution has been considered as one of the main environmental problems in the world nowadays. The source of soil heavy metal pollution in farmland, the effect of heavy metal pollution on soil quality in farmland, growth of crops, quality of agricultural products and the effects of heavy metal pollution on human health were discussed in this paper. The heavy metal pollution control measures were introduced, including physical and chemical regulations, phytoremediation and agroecological restoration measures. The future research perspective was also discussed in this paper.展开更多
By using the precise integration method, the numerical solution of linear quadratic Gaussian (LQG) optimal control problem was discussed. Based on the separation principle, the LQG central problem decomposes, or separ...By using the precise integration method, the numerical solution of linear quadratic Gaussian (LQG) optimal control problem was discussed. Based on the separation principle, the LQG central problem decomposes, or separates, into an optimal state-feedback control problem and an optimal state estimation problem. That is the off-line solution of two sets of Riccati differential equations and the on-line integration solution of the state vector from a set of time-variant differential equations. The present algorithms are not only appropriate to solve the two-point boundary-value problem and the corresponding Riccati differential equation, but also can be used to solve the estimated state from the time-variant differential equations. The high precision of precise integration is of advantage for the control and estimation. Numerical examples demonstrate the high precision and effectiveness of the algorithm.展开更多
To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is ...To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability.展开更多
Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis i...Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis infection control measures in health care facilities. To evaluate the effectiveness of infection control measures, such study was planned. Questionnaires were administered to all doctors, healthcare workers and servants working in outdoor and indoor department of tuberculosis at tertiary care hospital to assess the knowledge, attitudes and practices on prevention and control of Tuberculosis infection. A scoring system was devised to grade them. One-time audit was also done in outpatient and inpatient department. The analysis showed scoring of poor for doctors, good for nurses and poor forward aids. There is a need to develop strategies for training of health care workers on regular basis in order to reduce the incidence of nosocomial infections. Audit result shows a good level of environmental control measures. Better knowledge, attitude and practices are helpful for the prevention and control of tuberculosis. Also environmental control measures are helpful to prevent infection.展开更多
文摘This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global statistics of TB occurrence, it is evident that the national incidence of TB has reduced from 10.55 per 100,000 in 2015 to 8.36 per 100,000 in 2019;despite this, there are still some difficulties because migrants bring new strains of Mycobacterium tuberculosis. Hindrances, including language barriers and perceived immigration status, hinder patients from seeking medical attention or doctors from diagnosing diseases. Each patient and each cultural group need special attention to public health, enhancing living circumstances, and health care support. Community participation, inclusion of TB control programs into functional healthcare facilities, and the functioning of TB programs need to be stressed to address TB issues. Considering the focus on social, economic, and cultural approaches, the country can make severe advancements in TB control and population protection. This holistic analysis is critical for a long-term effective strategy to combat TB in the Kingdom.
文摘Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.
文摘Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and control,agricultural prevention and control,physical prevention and control,chemical prevention and control,and biological prevention and control can effectively control the damage of S.frugiperda and guarantee the safety of food production.The results will provide some reference for the prevention and control of S.frugiperda.
文摘Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology.
文摘Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,sharp decrease of global forest areas,soil erosion,acid rain pollution,water pollution and so on.This essay is to introduce the present status,formation causes and hazardous condition of acid rain pollution in china.Some feasible and effective control measures are put forward according to the actual situation in China.
文摘The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and actively carrying out comprehensive management to control the pests damage in the economic permissible level.
基金Supported by National Science Fund for Distinguished Young Scholars of China(41102107)Basic Research Program for Technology Innovation,Chang'an University(CHD2012JC080)~~
文摘[Objective] This study aimed to find out effective measures to solve land- scape water eutrophication. [Method] Based on an overview of the urban landscape water characteristics and pollution control situation, taking an example of the artificial lakes in a campus in Xi'an, we comparatively analyzed the present pollution situation of Xiuyuan Lake and Mingyuan Lake, and provided controlling measures against eutrophication pollution, as well as restoration measures. [Result] All the indicators (TN, TP, Chl-a, NH3-N, CODMn) of the landscape water quality in both Xiuyuan Lake and Mingyuan Lake went severely beyond the Grade IV standards, presenting a state of heavy eutrophication. Nitrogen, phosphorus and other nutrient salts carried by atmospheric precipitation and its runoff, as well as domestic garbage generated by human activities were primary exogenous pollutants of the artificial lakes. And the release of sediment pollutants was endogenous substances causing deterioration of water quality. [Conclusion] This paper presents some measures to control the pollution of artificial lakes, and provides scientific references for the construction, operation and management of artificial lakes, as well as maintenance of aquatic environment.
文摘[Objective] The aim was to investigate pesticide use in Qujing city and explore the control measures.[Method] Surveys were made on pesticide use by farmers in five vegetable bases in Qujing city by questionnaires to study pesticide use and existing problems by farmers.[Result] Some problems existed in pesticide use in Qujing,such as non-standard pesticide source,lower-recognition of pesticide and impacts of pesticide residues on environment,and without professional guidance.[Conclusion] The existing problems can be resolved by enhancing technical trainings of technicians or pesticide managers,strengthening pesticide promotion,and reinforcing examination of pesticide residues.
文摘In the article, status quo of oil pollution in China's offshore area was in- troduced, and the sources of oil pollution in the ocean were analyzed. Furthermore, the possible hazards of marine oil pollution were discussed and related countermea- sures were proposed, including implementation of laws and regulations, enhancing awareness of environment protection, improvement of pollution monitoring and early warning mechanism, physical treatment, chemical treatment and biological treatment. With economy development, the demand of oil is increasing accordingly. Hence, oil pollution has become an urgent issue to be solved for better exploration of oil and protection of marine environment.
基金supported by the Center for Public Health Security Research 2022 Policy Research Project(ggwsaqyjzx202205).
文摘Background:To analyze the epidemiological characteristics of varicella epidemics in Chongqing Municipality from 2014 to 2021,and to provide a scientific basis for the formulation of varicella prevention and control measures.Methods:Data on the incidence of varicella outbreaks and vaccination data in Chongqing from 2014 to 2021 were collected through the China Disease Control and Prevention Information System and statistically analyzed using descriptive epidemiological methods.Results:From 2014 to 2021,213,715 cases of varicella were reported in Chongqing Municipality,with an average annual incidence rate of 86.26/100,000,with a statistically significant difference(χ^(2)=24,972.069,P<0.001);varicella incidence is seasonal,with peaks in May/June and October/December each year,presenting a“double-peak distribution”.The average annual incidence rate of varicella in municipal districts was 90.74/100,000,which was higher than that of counties 69.62/100,000 and autonomous counties 84.04/100,000;the average annual incidence rate of varicella in males was 89.37/100,000,and in females,82.22/100,000,with the difference not being statistically significant;the age of onset of the disease was mainly in the group of people under 15 years of age,with a total of 190,021 cases reported(88.9%),with 5-9 years old(35.7%)as the high incidence age group.The incidence occupation was dominated by students in 133,733 cases(62.6%).Conclusion:The overall varicella epidemic in Chongqing is on the rise,and has obvious seasonal,regional and population distribution characteristics.The prevention and control of varicella epidemic should be strengthened,the publicity of varicella vaccine should be increased,and it is recommended that varicella vaccine should be included in the national immunization program.
基金This work was supported by the National Natural Science Foundation of China(31971731,41771121)the Xinjiang National Key Research and Development Program(2019B00005)+1 种基金the National Key Research and Development Program(2017YFC0506705)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2017476).
文摘Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the''Dead Sea''due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts.
基金supported by the China Special Grant for the Prevention and Control of Infectious Diseases[2012ZX10004907,2017ZX10105011]Natural Science Foundation of China[81473026]。
文摘Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in Western China.This study aimed to evaluate the strategy of hepatitis B prevention and control in Western China and identify potential areas and strategies for improvement.Methods Susceptible population vaccination,health education,professional training of doctors,and other prevention and control measures have been implemented in Wuwei city since 2010.Data were obtained from three representative cross-sectional serosurveys conducted in 2010,2013,and 2015.The serum samples were subjected to enzyme-linked immunosorbent assays to detect the following seromarkers:HBV surface antigen(HBsAg),antibody against hepatitis B surface antigen(anti-HBs),and antibody against hepatitis B core antigen(anti-HBc).Estimates of variance were determined using Taylor series linearization methods.Results The three serosurveys revealed decreases in the prevalence of HBsAg(7.19% in 2010 vs.6.51% in 2013 vs.5.87% in 2015)and anti-HBc positivity(43.89%vs.32.87%vs.28.46%)and an increase in the prevalence of anti-HBs positivity(49.07%vs.53.66%vs.53.72%)over time.From 2010 to 2015,the legally reported incidence of hepatitis B in Wuwei city decreased from 686.53/100,000 to 53.72/100,000.Notably,persistently high HBsAg-positive rates(above 5.40%)were observed among subjects aged 20–69 years old in the three serosurveys;the prevalence of HBsAg was above 1% among children younger than 10 years old.Furthermore,rural subjects had higher rates of HBsAg and anti-HBc positivity than their urban counterparts(6.04%vs.4.83% and 30.26%vs.20.35%,respectively)in 2015 but had a lower rate of anti-HBs positivity(49.68 vs.55.18%).Multivariate regression analysis showed that age,urban and rural areas,and education level were the main factors affecting HBV infection.Conclusion Although vaccine-based prevention and control measures reduced the rate of HBV infection in Wuwei City over time,the hepatitis B infection rate in children younger than 10 years was still higher than the national average level.Therefore,the prevention and control of mother-to-child transmission and the management of the infected should be the focus of future prevention and control work.
基金supported by grants from Zhejiang Health Bureau (2008B073)Zhejiang Education Bureau (Y200909640)
文摘BACKGROUND: Hemodialysis (HD) patients are at high risk of infection by hepatitis B virus (HBV) or hepatitis C virus (HCV). The present study was designed to determine the impact of quality control measures on the prevention of transmission of blood-borne viruses. METHODS: A total of 6182 adult maintenance HD patients from all HD units in Zhejiang Province were recruited on January 1, 2007. The baseline demographic and clinical characteristics were recorded and all patients were followed up until death or survival at 4 years later. The Quality Control Standards of Hemodialysis were gradually implemented in HD units. The HBV or HCV seroconversion rates of the recruited patients were calculated and compared every year during the observation period. RESULTS: The prevalence of HBV was 8.3% at the beginning of the study, and 6.6% for HCV. With the implementation of the HD quality control measures, the HBV seroconversion rate tended to decrease year by year (χ 2 =6.620, P=0.085), and the HCV seroconversion rate decreased significantly (χ 2 =10.41, P=0.015). Compared with the data in 2007, the HBV seroconversion rate (χ 2 =4.204, P=0.040, relative risk ratio 0.393, 95% CI 0.156-0.991) and the HCV seroconversion rate (χ 2 =7.373, P=0.007, relative risk ratio 0.386, 95% CI 0.189-0.787) decreased significantly in 2010. CONCLUSION: Quality control measures for HD decreased the seroconversion rates of HBV or HCV in HD patients, showing that updated quality control measures reduce the risk for transmission of blood-borne viruses in the HD population.
文摘[Objective] The aim was to analyze the current status and control measures of ecological restoration in Karst rocky desertification area of Guizhou.[Method] The current status and existing problems of ecological restoration in Karst rocky desertification area of Guizhou were studied firstly,and main control measures were put forward according to existing problems.[Result] At present,Karst rocky desertification area in Guizhou has suitable ecological environment,obvious control results and rich control experience,and there exist many problems like ambiguous concept of ecological restoration,biased control emphasis,single control measure and serious water shortage due to lagging engineering construction.Control measures mainly include combining natural restoration with artificial tending to speed up ecological restoration,reinforcing the restoration and rebuilding of development and construction project to prevent the deterioration of regional ecological environment,speeding up the construction of environmental friendly energy infrastructures to decrease the damage of vegetation by human activities,increasing industrial structure adjustment and greatly developing green industry and improving the investment in technological innovation to promote the rapid development of ecological restoration.[Conclusion] The study could provide scientific references for the ecological restoration in other Karst rocky desertification area in Southwest China.
文摘According to a lot of hydrological and environmental monitoring data, the condition of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is described. The occurrence and development of soil and water loss is analyzed. The conclusion is that: (1) generally, the situation of soil and water loss in the Lancang River Mekong River watershed (in Yunnan section, China) is light, however, soil and water loss in some regions is serious, especially in the middle reach area of the river; (2) soil and water loss in the Lancang River Mekong River (in Yunnan section, China) watershed presents developing tendency and it is mainly caused by human beings. In accordance with these results, the control measures for soil and water loss are discussed.
文摘Environmental pollution problem generated in dairy farming process is the bottleneck restricting development of animal husbandry. By using the investigation data from dairy farmers of Inner Mongolia,environmental pollution problem generated by dairy farming in Inner Mongolia and its cause were analyzed,and prevention and control measures were put forward. The research result showed that weak technology support of environmental treatment and environmental-protection awareness of dairy farmer and bad application effect of pollution control technology caused by lower education degree of dairy farmer were main reasons for environmental pollution problem. We should develop dairy circular economy,advocate a moderate scale,scientifically breed,and enhance training of pollution control technology and propaganda to protect environment.
文摘Soil pollution has been considered as one of the main environmental problems in the world nowadays. The source of soil heavy metal pollution in farmland, the effect of heavy metal pollution on soil quality in farmland, growth of crops, quality of agricultural products and the effects of heavy metal pollution on human health were discussed in this paper. The heavy metal pollution control measures were introduced, including physical and chemical regulations, phytoremediation and agroecological restoration measures. The future research perspective was also discussed in this paper.
文摘By using the precise integration method, the numerical solution of linear quadratic Gaussian (LQG) optimal control problem was discussed. Based on the separation principle, the LQG central problem decomposes, or separates, into an optimal state-feedback control problem and an optimal state estimation problem. That is the off-line solution of two sets of Riccati differential equations and the on-line integration solution of the state vector from a set of time-variant differential equations. The present algorithms are not only appropriate to solve the two-point boundary-value problem and the corresponding Riccati differential equation, but also can be used to solve the estimated state from the time-variant differential equations. The high precision of precise integration is of advantage for the control and estimation. Numerical examples demonstrate the high precision and effectiveness of the algorithm.
文摘To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability.
文摘Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis infection control measures in health care facilities. To evaluate the effectiveness of infection control measures, such study was planned. Questionnaires were administered to all doctors, healthcare workers and servants working in outdoor and indoor department of tuberculosis at tertiary care hospital to assess the knowledge, attitudes and practices on prevention and control of Tuberculosis infection. A scoring system was devised to grade them. One-time audit was also done in outpatient and inpatient department. The analysis showed scoring of poor for doctors, good for nurses and poor forward aids. There is a need to develop strategies for training of health care workers on regular basis in order to reduce the incidence of nosocomial infections. Audit result shows a good level of environmental control measures. Better knowledge, attitude and practices are helpful for the prevention and control of tuberculosis. Also environmental control measures are helpful to prevent infection.