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Influencing factors and preventive measures of infectious complications after intestinal resection for Crohn’s disease
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作者 Shi-Rong Lv Xiao Huang +4 位作者 Li-Yun Zhou Jie Shi Chu-Chu Gong Ming-Ke Wang Ji-Shun Yang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3363-3370,共8页
The incidence of Crohn’s disease(CD)has increased in recent years,with most patients requiring intestinal resection.Complications after intestinal resection for CD can lead to poor prognosis and recurrence,among whic... The incidence of Crohn’s disease(CD)has increased in recent years,with most patients requiring intestinal resection.Complications after intestinal resection for CD can lead to poor prognosis and recurrence,among which infectious complic-ations are the most common.This study aimed to investigate the common risk factors,including medications,preoperative nutritional status,surgery-related factors,microorganisms,lesion location and type,and so forth,causing infectious complications after intestinal resection for CD,and to propose corresponding preventive measures.The findings provided guidance for identifying suscept-ibility factors and the early intervention and prevention of infectious complic-ations after intestinal resection for CD in clinical practice. 展开更多
关键词 Crohn’s disease Intestinal resection Postoperative infectious complications Influencing factors preventive measures
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Review of preventive and constructive measures for coal mine explosions:An Indian perspective 被引量:5
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作者 Santosh Kumar Ray Asfar Mobin Khan +3 位作者 Niroj Kumar Mohalik Debashish Mishra Somu Mandal Jai Krishna Pandey 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期471-485,共15页
Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different... Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different prevention and constructive measures,and its recent development to avoid firedamp and coal dust explosion.Preventive legislation in core coal-producing countries,viz.China,USA,Australia,South Africa,and India related to firedamp and coal dust explosion are critically analysed.Accidents occurred due to explosion after Nationalisation of Coal Mines(1973)in India are listed.Prevention and constructive measures adopted in India are critically analysed with respect to the global mining scenario.Measures like methane credit concept,classification of mines/seams with respect to explosion risk zone,deflagration index;installation of automatic fire warning devices,canopy air curtain technology,explosion-prevention measures,such as fire-retardant materials,inhibitors,extinguishing agent,dust suppressor,and active explosion barrier are discussed in detail to avoid explosion and thereby adhering to zero accident policy due to coal mine explosion. 展开更多
关键词 Firedamp explosion Coal dust explosion preventive measures Constructive measures LEGISLATION
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Characteristics of coal resources in China and statistical analysis and preventive measures for coal mine accidents 被引量:3
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作者 Chaolin Zhang Peizhong Wang +2 位作者 Enyuan Wang Dapeng Chen Chao Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第2期45-57,共13页
In the process of green and smart mine construction under the context of carbon neutrality,China's coal safety situation has been continuously improved in recent years.In order to recognize the development of coal... In the process of green and smart mine construction under the context of carbon neutrality,China's coal safety situation has been continuously improved in recent years.In order to recognize the development of coal production in China and prepare for future monitoring and prevention of safety incidents,this study mainly elaborated on the basic situation of coal resources and national mining accidents over the past five years(2017-2021),from four dimensions(accident level,type,region,and time),and then proposed the preventive measures based on accident statistical laws.The results show that the storage of coal resources has obvious geographic characteristics,mainly concentrated in the Midwest,with coal resources in Shanxi and Shaanxi accounting for about 49.4%.The proportion of coal consumption has dropped from 70.2%to 56%between 2011 and 2021,but still accounts for more than half of the all.Meanwhile,the accident-prone areas are positively correlated with the amount of coal production.Among different levels of coal mine accidents,general accidents had the highest number of accidents and deaths,with 692 accidents and 783 deaths,accounting for 87.6%and 54.64%respectively.The frequency of roof,gas,and transportation accidents is relatively high,and the number of single fatalities caused by gas accidents is the largest,about 4.18.In terms of geographical distribution of accidents,the safety situation in Shanxi Province is the most severe.From the time distribution of coal mine accidents,the accidents mainly occurred in July and August,and rarely occurred in February and December.Finally,the"4+4"safety management model is proposed,combining the statistical results with coal production in China.Based on the existing health and safety management systems,the manage-ments are divided into four sub-categories,and more specific measures are suggested. 展开更多
关键词 Resource characteristics Coal mine accidents Security situation Safety 4+4 model preventive measures
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Safety Risks and Preventive Measures for Construction Supervision of Construction Projects 被引量:1
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作者 Ting Zhou 《Frontiers Research of Architecture and Engineering》 2018年第4期103-107,共5页
Based on the analysis of construction project safety risk and its preventive measures, it is first necessary to clarify the safety risks and existing problems of construction project supervision and to formulate effec... Based on the analysis of construction project safety risk and its preventive measures, it is first necessary to clarify the safety risks and existing problems of construction project supervision and to formulate effective construction procedures. It is necessary to check the production safety of the construction unit, strengthen the company's own safety production management, and reasonably control the risk to familiarize with the construction drawings, and make a special construction plan for the work of the bottom line. Finally, an elective solution is drawn to comprehensively expound the importance of construction project construction safety risk and its preventive measures. 展开更多
关键词 Cnstruction ENGINEERING CONSTRUCTION SUPERVISION SAFETY RISKS preventive measures
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A policy and technical measures for controlling soil and water loss in the Loess Plateau of China
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作者 Wu Qinxiao and Li YinchuNorthwestern Institute of Soil and Water Conservation Academia sinica,Shaanxi,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1990年第2期79-86,共8页
Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for... Loess Plateau is the most serious region of soil and water loss in China and the world. The sediment carried into the Yellow River amounts to 1.6 billion tons every year. This paper reviews the factors and reasons for erosion in this area, and puts forward a comprehensive controlling policy on the basis of the principles of ecology and practise of Chinese scientists for 40 years. In conformity with the policy, a number of technical measures for controlling soil and water loss are suggested. 展开更多
关键词 Loess Plateau soil and water loss controlling policy technical measure.
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Mothers’ Knowledge Regarding Preventive Measures of Food Poisoning in Yemen
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作者 Waled Amen Mohammed Ahmed 《Food and Nutrition Sciences》 2015年第1期49-53,共5页
Background: The WHO considers food poisoning the main cause of morbidity and mortality in developing countries, and the responsible for high levels of loss of productivity in developed countries. Objective: The study ... Background: The WHO considers food poisoning the main cause of morbidity and mortality in developing countries, and the responsible for high levels of loss of productivity in developed countries. Objective: The study aims to assess the mothers’ knowledge about preventive measures of food poisoning in Sharaab, Taiz, Yemen. Method: This is a descriptive study. It was conducted in Sharaab, Yemen during period extended from April to November 2014. It involved 180 mothers selected by simple random sampling. Data were collected by using designed structured and pre-tested questionnaire and then were analyzed by (SPSS) Version 20. Result: The findings showed that 60% of mothers have heard about food poisoning. The mothers’ knowledge about transmission of diseases by food was acceptable;68.9% knew. When they were asked to detail the diseases, cholera was the most reported by about 84.4%, diarrhea 50%, and food poisoning 22.2% only. Regarding the mothers’ knowledge about causes of food poisoning, about 65.5% of them mentioned contaminated food, and 49.4% mentioned contaminated hands while 37.2% of them mentioned contaminated utensils. The total knowledge was calculated;it was about 40.72%. Conclusion: It was found that, mothers’ knowledge about preventive measures of food poisoning is not satisfactory concerning most items including: food related diseases, causes of food poisoning and preventive measures for food poisoning such as hand washing, washing vegetables and cooking appropriately. The mothers in Yemen, Taiz, Sharaab have low level of knowledge about food poisoning prevention. There is a need for strengthening the situation through educational sessions. 展开更多
关键词 FOOD POISONING Mothers KNOWLEDGE LEVEL preventive measures
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Perception of Sexually Transmitted Infection-Preventive Measures among Senior Secondary School Students in Nnewi-North Local Government Area, Anambra State, Nigeria
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作者 Simeon Achunam Nwabueze Emmanuel Chukwunonye Azuike +6 位作者 Chijioke Amara Ezenyeaku Clifford Chidiebere Aniagboso Ebele Dabeluchukwu Azuike Ifeoma Chisom Iloghalu Charles Chukwudalu Ebulue Uzoamaka Ugochinyere Epundu Obinna Francis Nwone 《Open Journal of Preventive Medicine》 2014年第9期708-716,共9页
Background: Sexually transmitted infections-preventive measures are effective methods employed in the prevention of sexually transmitted infections [STIs]. Sexually transmitted infections are among the most common inf... Background: Sexually transmitted infections-preventive measures are effective methods employed in the prevention of sexually transmitted infections [STIs]. Sexually transmitted infections are among the most common infections in the world and therefore a major public health problem as they cause devastating long term consequences if untreated, especially in adolescents. Sexually transmitted infection-preventive measures, if correctly and consistently used, have been proven to be efficacious. Methodology: This was a cross-sectional descriptive study carried out among SS2 and SS3 students in Nnewi North Local Government Area of Anambra state, Nigeria. A structured, self administered questionnaire was administered to consenting senior secondary students to gather relevant information about socio-demogaraphic characteristics, knowledge about STIs, sexual behaviours. Three hundred and thirty four students participated in the study. Multi stage sampling technique was used. SPSS version 20 was used to analyze the data. Results were represented in tables and graphs. Results: Three hundred and thirty four students participated in the study, of which females and males are 167 each. 89% understood the meaning of STI. The majority of the respondents got the knowledge from TV/radio (34.4%), teachers (28.1%) and mother (27.0%). The majority of respondents knew that HIV/AIDS (89.8%), syphilis (58.1%) and Gonorrhoea (56.9%) were STIs. Good numbers of respondents knew the symptoms of STIs and risk factors of STI with unprotected sex and multiple sexual partners (57.5%) and (42.2%) respectively, as the highest risk factors. About 75.7% of respondents knew that HIV/AIDS cannot be cured. The Majority knew that avoiding sexual intercourse, being faithful to one partner and use of condom are preventive measures respectively. The majority of respondents (71%) felt they cannot be infected with an STI. 92.8% believed that STIs can be prevented. Age range for first sexual intercourse was 13 - 18 years for females and 8 - 19 years for males. Of the 86 that have had sexual intercourse, 48.8% had experienced one or more of the symptoms of STIs and the majority (80.9%) went to a hospital for treatment. Males (31.4%) are more likely to have multiple sexual partners than females (4.7%). Conclusion: The majority of the students had an objective knowledge on STIs transmission and prevention. Their overall attitude was positive but their practices were not satisfactory, especially for the males. Females were more careful and health conscious than their male counterpart. 展开更多
关键词 Knowledge Sexually Transmitted INFECTIONS preventive measures Students
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The Impact of Spring Disastrous Climate on Prunus sibirica var suavosperma Yield and Preventive Countermeasures
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作者 Zhou Guohua Li Yuhua +1 位作者 Bai Ruixing Lv Shangbin 《Meteorological and Environmental Research》 CAS 2015年第1期59-61,共3页
Using the data at standard ground observation field of Lingyuan Meteorological Bureau and comparative and parallel observation data during growth period of surrounding Prunus sibirica var suavosperma, and combining so... Using the data at standard ground observation field of Lingyuan Meteorological Bureau and comparative and parallel observation data during growth period of surrounding Prunus sibirica var suavosperma, and combining social investigation data about low-temperature cold injury loss of P. sibirica in recent years, it is found that low-temperature cold injury and abrupt change of temperature in spring are also important factors affecting P. sibirica yield and economic benefit. According to temperature indexes, meteorological department timely issues warning and forecast, and relevant departments and foresters take corresponding preventive measures, and strengthen cultivation technology and management of P. sibinca park. It avoids economic loss of P. sibirica caused by low-temperature cold injury, and obtains high and stable yield. 展开更多
关键词 P. sibinca Disastrous climate Low-temperature cold injury preventive measures China
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Legislative Countermeasures for Preventing and Controlling Water Pollution in Water-deficient Regions
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作者 Shi Yuanyuan Sun Changhong +1 位作者 An Tongyan Chen Dadi 《Meteorological and Environmental Research》 CAS 2014年第10期56-59,共4页
The shortage of water resources is severe in Beijing. The shortage of eco-environmental water and the sewage discharge over the environmental capacity are main bottlenecks that restrict the improvement of water enviro... The shortage of water resources is severe in Beijing. The shortage of eco-environmental water and the sewage discharge over the environmental capacity are main bottlenecks that restrict the improvement of water environment. The reuse of wastewater could not only reduce the discharge of pollutants,but it could also increase the consumption of eco-environmental water. Therefore the reuse of wastewater is an important approach to improve the water environmental quality. Combined with the formulation process of Regulations of Beijing on Prevention and Control of Water Pollution,the current situations of prevention and control of water pollution in Beijing,the discharge of pollutant,water environmental quality,the population and economic development and water resources and so on were analyzed. And the bottlenecks that restricted the improvement of water environmental quality were found. And the necessity of solving the control of water pollution by reusing the wastewater and ensuring the consumption of eco-environmental water was analyzed from the perspective of the control of water pollution. And some legislative countermeasures were put forward,which provided new ideas for solving the problem of the prevention and control of water pollution and improving the water environmental quality. It was of important reference values for local governments( especially water-deficient regions) to make relative polices or plans of water pollution control and water environmental protection. 展开更多
关键词 Water environment Pollution prevention and control REUSE Water resources LEGISLATION China
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Exploring individuals’ effective preventive measures against epidemics through reinforcement learning
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作者 Ya-Peng Cui Shun-Jiang Ni Shi-Fei Shen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期640-647,共8页
Individuals’ preventive measures,as an effective way to suppress epidemic transmission and to protect themselves from infection,have attracted much academic concern,especially during the COVID-19 pandemic.In this pap... Individuals’ preventive measures,as an effective way to suppress epidemic transmission and to protect themselves from infection,have attracted much academic concern,especially during the COVID-19 pandemic.In this paper,a reinforcement learning-based model is proposed to explore individuals’ effective preventive measures against epidemics.Through extensive simulations,we find that the cost of preventive measures influences the epidemic transmission process significantly.The infection scale increases as the cost of preventive measures grows,which means that the government needs to provide preventive measures with low cost to suppress the epidemic transmission.In addition,the effective preventive measures vary from individual to individual according to the social contacts.Individuals who contact with others frequently in daily life are highly recommended to take strict preventive measures to protect themselves from infection,while those who have little social contacts do not need to take any measures considering the inevitable cost.Our research contributes to exploring the effective measures for individuals,which can provide the government and individuals useful suggestions in response to epidemics. 展开更多
关键词 epidemic simulation complex networks reinforcement learning preventive measures
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Awareness about transmission and preventive measures of COVID-19 from mother to child: A cross-sectional study among pregnant women
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作者 Neetu Singh Sugandha Jauhari 《Asian pacific Journal of Reproduction》 2022年第6期261-268,共8页
Objective:To study the knowledge,attitude,and practice of pregnant women regarding transmission and preventive measures of COVID-19 from mother to child and to determine the reasons for vaccine hesitancy.Methods:This ... Objective:To study the knowledge,attitude,and practice of pregnant women regarding transmission and preventive measures of COVID-19 from mother to child and to determine the reasons for vaccine hesitancy.Methods:This observational cross-sectional knowledge,attitude,and practice study was conducted among pregnant women of any trimester,attending the antenatal care out-patient department of a tertiary care hospital in Lucknow from October 2020 to March 2021.All the participants were interviewed using a pretested semi-structured questionnaire for desired information.Reasons for vaccine hesitancy were also asked to assess their unwillingness to get vaccinated.Results:Totally 652 pregnant women were included and 91.3%were aware that COVID-19 spread through contact with an infected person and 85.3%knew that COVID-19 spread by respiratory droplets.Of pregnant women,95.7%perceived that social distancing and wearing a proper mask were effective ways to prevent SARS-CoV-2 infection and 96.8%of the pregnant women wore masks regularly when going out.Of pregnant women,79.0%were hesitant to get vaccinated.The most common reason was that COVID-19 vaccine can harm the developing fetus(77.5%)and was not very safe in pregnancy(75.0%).Conclusions:Of the pregnant women,22.92%have unsatisfactory knowledge regarding COVID-19,35.63%have negative attitude and 19.93%have poor practices,indicating that there are still gaps in awareness,and majority of them are unwilling to get vaccinated.Good awareness will help prevent the occurrence of future COVID-19 waves in India. 展开更多
关键词 COVID-19 Pregnant women AWARENESS TRANSMISSION preventive measures Vaccine hesitancy
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Hidden Dangers and Preventive Measures in the Inventory of Articles in Operating Room
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作者 Huang Yi Yajuan Ke +3 位作者 Hongying Zhu Suwen Lu Liurong Cheng Minghui Liu 《Open Journal of Preventive Medicine》 2021年第5期192-198,共7页
Operating Room is an important place for surgical diagnosis and treatment and rescue of patients. With the rapid development of medical technology, high, precision, sharp continuous development, operating room safety ... Operating Room is an important place for surgical diagnosis and treatment and rescue of patients. With the rapid development of medical technology, high, precision, sharp continuous development, operating room safety management is particularly important. The error of the counting of the surgical articles causes the foreign body left in the patient’s body, which will cause irreversible damage to the patient and even cause the medical dispute and touch the legal problem. Operation items inventory system is an important working system in the operating room. Scientific and standardized methods and systems for counting surgical instruments and dressings during operation can prevent foreign bodies from being left in the body, prevent errors and accidents in the operating room, and are very important for ensuring the safety of the operation of patients. In order to ensure the safety of patients, it is necessary to ensure the correct inventory of surgical items. The factors affecting the accuracy of item counting in the operating room and the preventive measures are summarized as follows. 展开更多
关键词 Operating Room ARTICLES Hidden Danger of Safety preventive measures Reference
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Research on Failure Analysis Method and Preventive Measures of Coal Mine Machinery Bearing
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作者 Yuan Xufang 《环境科学前沿(中英文版)》 2019年第1期13-16,共4页
For coal mine production, the role of mechanical bearings is to provide basic support for the transportation of mining coal resources. For coal production, because of its large production capacity and intensive produc... For coal mine production, the role of mechanical bearings is to provide basic support for the transportation of mining coal resources. For coal production, because of its large production capacity and intensive production, mechanical bearings will wear under the influence of high strength and high load in coal transportation, which will lead to bearing failure in the long run, thus affecting the transportation efficiency of coal resources. In order to improve this situation, it is necessary to analyze the wear failure of coal mine mechanical bearings, and to formulate corresponding preventive measures accordingly. Based on this, this paper focuses on the analysis method of mechanical bearing wear failure, and puts forward corresponding preventive measures, in order to effectively improve the current situation of coal mine production. 展开更多
关键词 COAL MINE MACHINERY BEARING FAILURE Analysis Method preventive measures
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Common Sports Injuries and Preventive Measures for Athletes—Take The Track and Field Team Athletes in Yushan County as an Example
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作者 Jieqiong Xie 《教育研究前沿(中英文版)》 2019年第4期313-317,共5页
Taking the common sports injuries and preventive measures of Yushan County middle school track and field athletes as the research object,the sports injuries of Yushan County middle school track and field athletes were... Taking the common sports injuries and preventive measures of Yushan County middle school track and field athletes as the research object,the sports injuries of Yushan County middle school track and field athletes were investigated and analyzed from the angle,type,location and nature of sports injury.Research on sports injury problems,trying to find the causes of sports injuries in daily training of track and field athletes,and proposed targeted preventive measures based on the specific situation of Yushan County Middle School.The results show that 77.70%of track and field athletes have suffered sports injury and periostitis and ligament/muscle strains are the most common forms of injury,and lower limbs are more prone to sports injuries than upper limbs. 展开更多
关键词 Middle School Track and Field Sports Injuries preventive measures
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Adherence to Preventive Measures during the COVID-19 Pandemic among University Students in Sudan
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作者 Einas Mustafa Mudawi Ahmed Sahar Moawia Balla Elnour +5 位作者 Sozan M. Abdelkhalig Tayseer Abdelmotalib Ahmed Taha Sulafa Abdelbagi Mustafa Ahmed Jalal Abdelrasool Hassan Eltaib Najad G. Mustafa Samar Moawia Balla Elnour 《Open Journal of Internal Medicine》 2023年第4期408-426,共19页
Background: Coronavirus disease 2019, otherwise known as COVID-19, emerged in December of 2019. COVID-19 spreads through an airborne transmission route. Preventive measures were described to help decrease the spread o... Background: Coronavirus disease 2019, otherwise known as COVID-19, emerged in December of 2019. COVID-19 spreads through an airborne transmission route. Preventive measures were described to help decrease the spread of COVID-19 worldwide. There were a number of preventive measures that were globally adopted: social distance of at least 1 meter, mask wearing, washing hands for 20 seconds, and covering the mouth and nose if the person sneezes or coughs. Methods: A descriptive cross-sectional study among 362 students from the International University of Africa, Sudan, was carried out between August 2021 and September 2022. Statistical Package for Social Sciences version 26 was used for data analysis;frequency and percentage were used to describe the qualitative variables. A chi-square test was used for association analysis;a P-value ≤ 0.05 was considered statistically significant. Results: Among study participants, the females were 70.9%;most were 20 - 23 years old (73.6%). 54.2% were vaccinated against COVID-19;83.6% had good knowledge regarding the mode of transmission, and 76.1% stayed in during quarantine. 80.6% of participants understood social distancing correctly. 76.1% of males and 45.1% of females started or completed vaccination (P ≤ 0.05). 51.4% of males and 81.3% of females adhered to preventive measures (P ≤ 0.05). Conclusions: It is important to target health education campaigns and interventions to improve adherence to preventive measures among university students. Although the pandemic is coming to an end, a lesson should be learned from it, and future preparation should be employed. 展开更多
关键词 SUDAN COVID-19 preventive measures ADHERENCE
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Preventive Measures to be Taken to Reduce Birth Defects
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《China Population Today》 2002年第4期16-17,共2页
关键词 preventive measures to be Taken to Reduce Birth Defects
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Cause Analysis and Preventive Measures of Drug Shortage
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作者 Zhou Ziyang Ma Jia +2 位作者 Liu Fuyao Liu Yuhan Sun Lihua 《Asian Journal of Social Pharmacy》 2022年第2期120-131,共12页
Objective To study the current situation and the root cause of drug shortage in China, and put forward countermeasures and suggestions accordingly for relevant national policy decisions. Methods Based on literature re... Objective To study the current situation and the root cause of drug shortage in China, and put forward countermeasures and suggestions accordingly for relevant national policy decisions. Methods Based on literature research, questionnaire survey and expert consultation, the causes of drug shortage in China were comprehensively investigated, and fishbone diagram was used to further analyze the logical relationship among the causes. Results and Conclusion The main reasons for the shortage of drugs are the low profit of production enterprises and insufficient active pharmaceutical ingredients (APIs). The other reasons include uncertain demand, standard problem and few exclusive manufacturers. Besides, the monopoly of circulation enterprises also leads to the shortage of drugs to a certain extent. It is suggested that we should increase the punishment of monopoly, optimize the market environment, and establish a reasonable drug price mechanism. In addition, enterprises should participate in the information communication platform of medical institutions to solve the asymmetry between supply and demand. The research on clinical drugs to substitute drugs in need should be strengthened, and the reporting system of drug discontinuation should be improved. 展开更多
关键词 drug shortage CAUSES preventive measure
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A New Device for Gas-Liquid Flow Measurements Relying on Forced Annular Flow
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作者 Tiantian Yu Youping Lv +5 位作者 Hao Zhong Ming Liu Pingyuan Gai Zeju Jiang Peng Zhang Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1759-1772,共14页
A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The sw... A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The swirling blades are used to transform the complex flow pattern into a forced annular flow.Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory,a formula is introduced to measure the phase-separated flow of gas and liquid.The formula requires the pressure ratio,Lockhart-Martinelli number(L-M number),and the gas phase Froude number.The unknown parameters appearing in the formula are fitted through numerical simulation using computational fluid dynamics(CFD),which involves a comprehensive analysis of the flow field inside the device from multiple perspectives,and takes into account the influence of pressure fluctuations.Finally,the measurement model is validated through an experimental error analysis.The results demonstrate that the measurement error can be maintained within±8%for various flow patterns,including stratified flow,bubble flow,and wave flow. 展开更多
关键词 Gas-liquid flow measurement blocking flowmeter measurement model pressure fluctuations numerical simulation experimental control
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Transient Stability Preventive Control of Wind Farm Connected Power System Considering the Uncertainty
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作者 Yuping Bian Xiu Wan Xiaoyu Zhou 《Energy Engineering》 EI 2024年第6期1637-1656,共20页
To address uncertainty as well as transient stability constraints simultaneously in the preventive control of windfarm systems, a novel three-stage optimization strategy is established in this paper. In the first stag... To address uncertainty as well as transient stability constraints simultaneously in the preventive control of windfarm systems, a novel three-stage optimization strategy is established in this paper. In the first stage, the probabilisticmulti-objective particle swarm optimization based on the point estimate method is employed to cope with thestochastic factors. The transient security region of the system is accurately ensured by the interior point methodin the second stage. Finally, the verification of the final optimal objectives and satisfied constraints are enforcedin the last stage. Furthermore, the proposed strategy is a general framework that can combine other optimizationalgorithms. The proposed methodology is tested on the modified WSCC 9-bus system and the New England 39-bussystem. The results verify the feasibility of the method. 展开更多
关键词 Transient preventive control chance-constrained programming multi-objective PSO TSCOPF wind farm
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Impact of Migrant Populations on Tuberculosis Rates in Saudi Arabia: Assessing How Migration Patterns Affect TB Incidence and Control Measures: A Narrative Review
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作者 Neda Ali Al Bati 《Journal of Tuberculosis Research》 2024年第3期165-181,共17页
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
关键词 Kingdom Saudi Arabia (KSA) Tuberculosis (TB) Prevalence MIGRANTS Control measures
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