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Leading Pattern of Spring Drought Variability over East Asia and Associated Drivers
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作者 赵庆红 杨崧 +1 位作者 田红瑛 邓开强 《Journal of Tropical Meteorology》 SCIE 2024年第1期1-10,共10页
Drought events have become more frequent and intense over East Asia in recent decades,leading to huge socioeconomic impacts.Although the droughts have been studied extensively by cases or for individual regions,their ... Drought events have become more frequent and intense over East Asia in recent decades,leading to huge socioeconomic impacts.Although the droughts have been studied extensively by cases or for individual regions,their leading variability and associated causes remain unclear.Based on the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis product from 1979 to 2020,this study evealuates the severity of spring droughts in East Asia and investigates their variations and associated drivers.The results indicate that North China and Mongolia have experienced remarkable trends toward dryness during spring in recent decades,while southwestern China has witnessed an opposite trend toward wetness.The first Empirical Orthogonal Function mode of SPEI variability reveals a similar seesawing pattern,with more severe dryness in northwestern China,Mongolia,North China,South Korea,and Japan but increased wetness in Southwestern China and southeast Asia.Further investigation reveals that the anomalously dry(wet)surface in North(Southwestern)China is significantly associated with anomalously high(low)temperature,less(more)precipitation,and reduced(increased)soil moisture during the previous winter and early spring,regulated by an anomalous anticyclone(cyclone)and thus reduced(increased)water vapor convergence.The spring dry-wet pattern in East Asia is also linked to cold sea surface temperature anomalies in the central-eastern Pacific.The findings of this study have important implications for improving the prediction of spring drought events in East Asia. 展开更多
关键词 DROUGHT leading pattern East Asia spring drivers
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Knowledge, Attitudes and Practices Relating to HIV among Motorbike Taxi Drivers in Parakou, Benin, in 2021
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作者 Luc Béhanzin Anicette Yénoukounmè Mahoutin Akodjetin +6 位作者 Yessito Corine Nadège Houéhanou-Sonou Virginie Mongbo Phinées Adégbola Menakpo Ferdinand Adounkpè Maurice Togbédji Agonnoudé David Houéto Thierry Adoukonou 《Open Journal of Epidemiology》 2024年第2期260-272,共13页
Background and Objective: HIV infection is a major global Public Health threat worldwide, particularly in Sub-Saharan Africa of which Benin. The level of knowledge determines the attitudes and behaviors of the populat... Background and Objective: HIV infection is a major global Public Health threat worldwide, particularly in Sub-Saharan Africa of which Benin. The level of knowledge determines the attitudes and behaviors of the populations towards this infection. The study objective was to assess knowledge, attitudes and practices related to HIV infection among motorbike taxi drivers (MTD) in Parakou in 2021. Methods: This was a descriptive cross-sectional study targeting MTD in Parakou in 2021. Participants were selected by cluster sampling. Pretested Digitized questionnaire using KoboCollect<sup>@</sup> applicationserved as a data collection tool. Knowledge, attitudes and practices variable were treated on a score scale. A knowledge score was considered to reflect a good knowledge of HIV if at least two-thirds of the knowledge statements had been correctly answered provided the subject recognized the sexual route as one of modes of HIV transmission, identified at least one preventive measure and meant the incurability of the disease. Quantitative and qualitative variables were appropriately described using the EPI Info 7.1.3.3 software. The participant was classified at positive attitude/practice for HIV prevention, when it has a score of at least 80% and suggests a good preventive measure face a risk of exposure to HIV. Results: A total of 374 subjects were recruited into the study. The mean age was 31.51 ± 7.76 years. Most participants (86.06%) had good knowledge of condom use as an HIV prevention method. The sources of information mentioned were mainly the media (77.07%), relatives or friends (63.38%), and field-workers from non-governmental organizations (37.26%). Routine HIV testing was 50.53%. Among participants, 76.10% reported at least two different sexual partners. Condom use was 59.18 % during the casual sexual intercourse. Within the client-provider relationship with female sex workers, 33.17% had had sexual intercourse with them. The sexual route was the most cited (92.99%), and 90.23% stated that HIV infection can be stabilized by medication in a health structure. Conclusion: The level of knowledge of motorbike taxi drivers in Parakou does not match their behavior with regard to HIV prevention. Appropriate strategies are needed to develop prevention skills in this population. To effectively comb at HIV, it will be necessary to strengthen the targeted HIV preventive interventions at key and bridge populations including motorbike taxi drivers in Benin. 展开更多
关键词 KNOWLEDGE PRACTICE HIV Motorbike Taxi drivers BENIN
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Seroprevalence Survey of HIV and Hepatitis B Virus and Behavioral Characteristics among Heavy Truck Drivers along Port Sudan-Khartoum Highways
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作者 Sara S. Osman Adam A. Mattar Omnia M. Hamid 《Open Journal of Medical Microbiology》 2024年第1期11-22,共12页
The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The pr... The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan. 展开更多
关键词 Sexual Transmitted Infection Port Sudan Truck drivers/Assistance
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Statistical Analysis of Accident Proneness of Drivers
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作者 S.V.Gerus 《Journal of Traffic and Transportation Engineering》 2024年第2期81-91,共11页
A mathematical model describing the risks of road accidents has been built on the basis of statistical data of drivers’ accident rate. It has been revealed that drivers can be divided by the degree of their accident ... A mathematical model describing the risks of road accidents has been built on the basis of statistical data of drivers’ accident rate. It has been revealed that drivers can be divided by the degree of their accident proneness into four categories with sharply differing probabilities of road accidents. It has been shown that there is a possibility of classification of drivers in accordance with specified categories. 展开更多
关键词 ACCIDENT PROBABILITY DRIVER CATEGORY classification proneness
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Exploring the drivers of urban expansion in a medium-class urban agglomeration in India using the remote sensing techniques and geographically weighted models
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作者 Tirthankar Basu Arijit Das Paulo Pereira 《Geography and Sustainability》 CSCD 2023年第2期150-160,共11页
Rapid urbanization urges the immediate attention of policymakers to ensure sustainable city development.Under-standing the urban growth drivers is essential to address effective strategies for urbanization-related cha... Rapid urbanization urges the immediate attention of policymakers to ensure sustainable city development.Under-standing the urban growth drivers is essential to address effective strategies for urbanization-related challenges.This work aims to study Raiganj’s urban development and the factors associated with this expansion.This study employed global logistic regression(LR)and geographical weighted logistic regression(GWLR)to explore the role of different factors.The results showed that the role of the central business district(covariate>-1),commercial market(covariate>-3),and police station(covariate>-4)were significant to the development of new built-up areas.In the second period,major roads(covariate>-2)and new infrastructures(covariate>-4)became more relevant,particularly in the eastern and southern areas.GWLR was more accurate in assessing the different fac-tors’impact than LR.The results obtained are essential to understanding urban expansion in India’s medium-class cities,which is critical to effective policies for sustainable urbanization. 展开更多
关键词 drivers Geographically weighted logistic regression (GWLR) Logistic regression LULC Urban growth
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Higher Plasma Potassium Level Reduces 10-Year Cardiovascular Disease Risk Predicted by the Framingham Risk Score among Taxi-Motorbike Drivers Residing and Working in Cotonou, Benin
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作者 Patrice Hodonou Avogbe Ambaliou Sanni 《Journal of Biosciences and Medicines》 2023年第4期417-430,共14页
Hypertension, obesity, smoking, dyslipidemia, and type 2 diabetes (T2D) are the major risk factors for developing cardiovascular diseases (CVD). Recent studies revealed that taxi-motorbike drivers (TMDs) in Cotonou ha... Hypertension, obesity, smoking, dyslipidemia, and type 2 diabetes (T2D) are the major risk factors for developing cardiovascular diseases (CVD). Recent studies revealed that taxi-motorbike drivers (TMDs) in Cotonou had higher rates of CVD risk factors, but their impacts on cardiovascular events have rarely been studied. The Framingham risk score (FRS) is an algorithm that considers CVD risk factors and estimates the risk of developing CVD in the next 10 years. Our objectives were to assess the 10-year CVD risk predicted by the FRS, and to examine the relationships of 10-year CVD risk with plasma iron and potassium levels among TMDs. We included 134 TMDs (22 - 59 years old) who had no prior diagnosis of CVD or T2D, and not taking medications affecting iron and potassium homeostasis. Conventional cardiovascular risk factors were used to calculate the 10-year CVD risk, which was categorized as low (20%). FRS > 2%, which corresponded to the 75th percentile of FRS distribution in our study population, was used as a cut-off value to classify participants into two groups. Plasma iron and potassium levels were segregated into tertiles and their associations with 10-year CVD risk were quantified by multivariate-adjusted logistic regression to calculate the odd ratios (ORs) to being above the 75<sup>th</sup> percentile of 10-year CVD risk with the corresponding 95% confidence intervals (CIs). We found that 62.0% of participants had at least one of cardiovascular risk factors. Approximately 97.8% of TMDs had 10-year CVD risk 4.8 mmol/L led to an 83% risk reduction of having 10-year CVD risk > 2% (OR = 0.17, 95% CI: 0.04 - 0.82, P = 0.027). In conclusion, our findings showed that high plasma potassium levels associate with reduced 10-year CVD risk among TMDs. Interventions focused on monitoring of plasma potassium, particularly in those with existing cardiovascular risk factors, may help prevent CVD. 展开更多
关键词 Cardiovascular Diseases 10-Year CVD Risk Cotonou Framingham Risk Score Plasma Potassium Taxi-Motorbike drivers
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Impact of Manipulative Treatment on Professional Drivers
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作者 Mauro D’Alessandro Anna Fulvio 《World Journal of Neuroscience》 2023年第4期242-256,共15页
The experimental research, presented in the study, focuses on track tests with the aim of highlighting changes in lap times after manipulative treatment of drainage of the glymphatic system and stimulation of the symp... The experimental research, presented in the study, focuses on track tests with the aim of highlighting changes in lap times after manipulative treatment of drainage of the glymphatic system and stimulation of the sympathetic nervous system. Introduction: The experimental research, presented in this study, focuses on analyzing the potential effects of a manipulative treatment on the performance of a professional driver. The main objective is to evaluate the change in lap times after the application of the treatment, trying to understand whether it can actually positively influence the driver’s performance. The study stands an important opportunity to extend knowledge, regarding the use of manipulative therapies in the context of optimized driving skills. The results obtained could provide useful insights and contribute to improving the performance of professional drivers by offering new perspectives and strategies to improve their performance. Leveraging a rigorous scientific approach and a sample of highly skilled drivers, the research aims to provide concrete evidence on the effectiveness of manipulative treatment in driving skills. Monitoring lap times before and after the intervention also capture any temporary or long-term effects of the treatment, ensuring a thorough and reliable analysis of the results. Materials and methods: 15 professional drivers, aged 18 to 36 years, with at least 10 years of experience as drivers, participated in this study. The test consisted of analyzing lap times before and after treatment. 展开更多
关键词 drivers Manipulative Treatment Sympathetic Nervous System Glymphatic System
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Drivers of Innovative Urban and Peri-Urban Agriculture in Bamenda City, Cameroon
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作者 Ngesang Ngiqueh Ngetleh Mary Juliet Bime-Egwu Mbu Daniel Tambi 《Agricultural Sciences》 2023年第9期1133-1152,共20页
Urban and peri-urban agriculture (UPA) is gaining increasing importance in developing countries, due to rapid urbanization and rising rural-to-urban migration which has led to an increase in the population of the urba... Urban and peri-urban agriculture (UPA) is gaining increasing importance in developing countries, due to rapid urbanization and rising rural-to-urban migration which has led to an increase in the population of the urban poor in Cameroon. It has been estimated that at least 70% of the total population of Cameroon will be living in urban areas by 2060. Urban and peri-urban agriculture (UPA) has become an important source of livelihood and survival, especially amongst the urban poor but is not adequately recognized and supported by the government of Cameroon and organizations. Recent innovations in UPA have created new opportunities for social, economic, and environmental sustainability of urban areas, hence possible policy formulation in UPA. Therefore, this study was conducted with the main objective of determining the drivers of innovative urban and peri-urban agriculture in Bamenda City, Cameroon. Methodologically, the study employed probit model, using primary data collected from a sample of 402 UPA farmers through the cluster, simple random, and snowball sampling techniques. The results revealed that access to extension services is a major driver of innovative UPA in Bamenda City and is statistically significant at 1%. Other factors such as employment status (full time), age group (26 to 50 years), and gender, were also seen to have a significant positive influence on innovative UPA while the level of education (secondary) had a negative influence on innovative UPA and was statistically significant at 5%. Limited capital, limited knowledge, and financial constraints were identified as the major challenges hindering the practice of innovative urban and peri-urban agriculture in Bamenda City. The study recommends that the government and non-governmental organizations should increase the quality and quantity of extension service delivery to urban and peri-urban farmers, and more recognition and support should be offered to them to help overcome the challenges faced. 展开更多
关键词 drivers Innovation Urban and Peri-Urban Agriculture Bamenda City
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Prevalence and Factors Associated with Psychoactive Substance Misuse among Heavy Goods Vehicle Drivers in Cotonou, Benin
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作者 Yolaine Glèlè-Ahanhanzo Nouriat Mohammed +3 位作者 Donatien Daddah Nicolas Gaffan Lamidhi Salami Alphonse Kpozehouen 《Open Journal of Epidemiology》 2023年第4期260-275,共16页
Introduction: In Benin, Heavy Goods Vehicle (HGV) drivers play an essential role in the logistics chain, facilitating the transportation of goods within the country or between other countries in the sub-region. HGV dr... Introduction: In Benin, Heavy Goods Vehicle (HGV) drivers play an essential role in the logistics chain, facilitating the transportation of goods within the country or between other countries in the sub-region. HGV drivers are professionals who experience adverse working conditions, exposing them to risky behaviours, including Psychoactive Substance (PAS) misuse, leading to particularly severe road accidents. This study aimed to determine the prevalence of PAS misuse among HGV drivers and identify associated factors in Cotonou, Benin. Materials and Methods: We conducted a cross-sectional survey involving HGV drivers at parking areas in Cotonou from 26 March to 10 April 2023. The dependent variable was the PAS misuse by HGV drivers, and the independent variables were related to their socio-demographic characteristics, health status and lifestyle habits, and professional characteristics. Data analysis involved determining the prevalence of PAS misuse with a 95% Confidence Interval (95% CI). Subsequently, we identified factors associated with PAS misuse among the participants using multivariate logistic regression. We presented the final regression results as adjusted odds ratios (aOR) with 95% CI. Results: The study included 425 HGV drivers. Among them, 53 (12.47%, 95% CI = 9.64 - 15.98) were misusing PAS. Compared to drivers aged 35 and older, those aged under 25 (aOR = 10.67, 95% CI = 3.56 - 32.03) and those aged 25 to 34 (aOR = 3.47, 95% CI = 1.37 - 8.82) had higher odds of PAS misuse. Drivers with a primary education were less likely (aOR = 0.43, 95% CI = 0.19 - 0.97) to misuse PAS than those with no formal education. Drivers suffering from cardiovascular diseases were also three times more likely (aOR = 3.08, 95% CI = 1.08 - 8.81) to misuse PAS than others. The odds of PAS misuse were also higher among drivers who reported taking breaks than those claiming not to (aOR = 3.11, 95% CI = 1.57 - 6.18). Conclusion: Driving under the influence of PAS is a risk factor for road accidents, associated with other factors highlighted in this study. Addressing these factors in prevention strategies through integrated approaches could lead to more effective results. 展开更多
关键词 Transportation ALCOHOL Psychoactive Substance Driver PROFESSIONAL BENIN
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Old, Diseased and Unfit to Drive a Motor Vehicle? An Evidence-Based View on Risk Factors among Senior Drivers in Germany
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作者 Thomas Wagner Thomas Friedrich Anne Voigt 《Journal of Traffic and Transportation Engineering》 2021年第1期8-18,共11页
The present study aimed to identify risk factors among older adult drivers from realistic data in order to stimulate the development of appropriate safety measures in the future.For this purpose,N=400 archived case fi... The present study aimed to identify risk factors among older adult drivers from realistic data in order to stimulate the development of appropriate safety measures in the future.For this purpose,N=400 archived case files from the driving authority in Dresden(Germany),were systematically analysed.The risk criterion was the outcome of the fitness to drive(FTD)assessment required by the authority.The results show that there are several significant risk factors(aged over 80,dementia,multi-morbidity and involvement into complex accidents)that can serve as cues for being unfit to drive.The practical measures for enhancing traffic safety are discussed. 展开更多
关键词 Older adult drivers FTD impaired drivers driver assessment risk factors incapability
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Flood Generation Mechanisms and Potential Drivers of Flood in Wabi-Shebele River Basin, Ethiopia
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作者 Fraol Abebe Wudineh Semu Ayalew Moges Belete Berhanu Kidanewold 《Natural Resources》 2022年第1期38-51,共14页
<span style="font-family:""><span style="font-family:Verdana;">Flood is a natural process generated by the interaction of various driving fac</span><span style="font-... <span style="font-family:""><span style="font-family:Verdana;">Flood is a natural process generated by the interaction of various driving fac</span><span style="font-family:Verdana;">tors. Flood peak flows, flood frequency at different return periods, and potential driving forces are analyzed in this study. The peak flow of six gauging stations, with a catchment area ranging from 169 -</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">124,108 km</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and sufficient observed streamflow data, was selected to develop threshold (3</span><sup><span style="font-family:Verdana;">rd</span></sup><span style="font-family:Verdana;"> quartile) magnitude and frequency (POTF) that occurred over ten years of records. Sixteen Potential climatic, watershed and human driving factors of floods in the study area were identified and analyzed with GIS, Pearson’s correlation, and Principal Correlation Analysis (PCA) to select the most influential factors. Eight of them (MAR, DA, BE, VS, sand, forest AGR, PD) are identified as the most significant variables in the flood formation of the basin. Moreover, mean annual rainfall (MAR), drainage area (DA), and lack of forest cover are explored as the principal driving factors for flood peak discharge in Wabi-Shebele River Basin. Fi</span></span><span style="font-family:""><span style="font-family:Verdana;">nally, the study resulted in regression equations that helped plan and design different infrastructure works in the basin as ungauged catchment empirical</span><span><span style="font-family:Verdana;"> equations to compute Q</span><sub><span style="font-family:Verdana;">MPF</span></sub><span style="font-family:Verdana;">, Q</span><sub><span style="font-family:Verdana;">5</span></sub><span style="font-family:Verdana;">, Q</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;">, Q</span><sub><span style="font-family:Verdana;">50</span></sub><span style="font-family:Verdana;">, and Q</span><sub><span style="font-family:Verdana;">100</span></sub><span style="font-family:Verdana;"> using influential climate, watershed, and human driving factors. The results of these empirical equations are </span></span><span style="font-family:Verdana;">also statistically accepted with a high significance correlation (R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> > 0.9). 展开更多
关键词 Flood drivers Climate Factors Watershed Characteristics Human drivers Principal Correlation Analysis (PCA) Multiple Regression Model
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Abiotic and biotic drivers of species diversity in understory layers of cold temperate coniferous forests in North China 被引量:8
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作者 Hui Wang Mengtao Zhang Hongwei Nan 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2213-2225,共13页
Understory plants are important components of forest ecosystems and play a crucial role in regulating community structures,function realization,and community succession.However,little is known about how abiotic and bi... Understory plants are important components of forest ecosystems and play a crucial role in regulating community structures,function realization,and community succession.However,little is known about how abiotic and biotic drivers affect the diversity of understory species in cold temperate coniferous forests in the semiarid climate region of North China.We hypothesized that(1)topographic factors are important environmental factors affecting the distribution and variation of understory strata,and(2)different understory strata respond differently to environmental factors;shrubs may be significantly affected by the overstory stratum,and herbs may be more affected by surface soil conditions.To test these hypotheses,we used the boosted regression tree method to analyze abiotic and biotic environmental factors that influence understory species diversity,using data from 280 subplots across 56 sites in cold temperate coniferous forests of North China.Elevation and slope aspect were the dominant and indirect abiotic drivers affecting understory species diversity,and individual tree size inequality(DBH variation)was the dominant biotic driver of understory species diversity;soil water content was the main edaphic factors affecting herb layers.Elevation,slope aspect,and DBH variation accounted for 36.4,14.5,and 12.1%,respectively,of shrub stratum diversity.Shrub diversity decreased with elevation within the range of altitude of this study,but increased with DBH variation;shrub diversity was highest on north-oriented slopes.The strongest factor affecting herb stratum species diversity was slope aspect,accounting for 25.9%of the diversity,followed by elevation(15.7%),slope(12.2%),and soil water content(10.3%).The highest herb diversity was found on southeast-oriented slopes and the lowest on northeast-oriented slopes;herb diversity decreased with elevation and soil water content,but increased with slope.The results of the study provide a reference for scientific management and biodiversity protection in cold temperate coniferous forests of North China. 展开更多
关键词 ABIOTIC and biotic drivers Cold TEMPERATE CONIFEROUS forests North China SEMI-ARID region UNDERSTORY species diversity
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Lattice models of traffic flow considering drivers' delay in response 被引量:3
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作者 祝会兵 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1322-1327,共6页
This paper proposes two lattice traffic models by taking into account the drivers' delay in response. The lattice versions of the hydrodynamic model are described by the differential-difference equation and differenc... This paper proposes two lattice traffic models by taking into account the drivers' delay in response. The lattice versions of the hydrodynamic model are described by the differential-difference equation and difference-difference equation, respectively. The stability conditions for the two models are obtained by using the linear stability theory. The modified KdV equation near the critical point is derived to describe the traffic jam by using the reductive perturbation method, and the kink-antikink soliton solutions related to the traffic density waves are obtained. The results show that the drivers' delay in sensing headway plays an important role in jamming transition. 展开更多
关键词 lattice hydrodynamic model traffic jams analytical method drivers delay in response
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Influences of Switching Jitter on the Operational Performances of Linear Transformer Drivers-Based Drivers 被引量:2
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作者 刘鹏 孙凤举 +3 位作者 魏浩 王志国 尹佳辉 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第4期347-352,共6页
A whole circuit model of a linear transformer drivers (LTD) module composed of 60 cavities in series was developed in the software PSPICE to study the influence of switching jitter on the operational performances of... A whole circuit model of a linear transformer drivers (LTD) module composed of 60 cavities in series was developed in the software PSPICE to study the influence of switching jitter on the operational performances of LTDs. In the model, each brick in each cavity is capable of operating with jitter in its switch. Additionally, the manner of triggering cables entering into cavities was considered. The performances of the LTD module operating with three typical cavity-triggering sequences were simulated and the simulation results indicate that switching jitter affects slightly the peak and starting time of the output current pulse. However, the enhancement in switching jitter would significantly lengthen the rise time of the output current pulse. Without considering other factors, a jitter lower than 10 ns may be necessary for the switches in the LTD module to provide output current parameters with an acceptable deviation. 展开更多
关键词 linear transformer drivers (LTDs) circuit model pulsed power transmission line JITTER trigger delay
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Drivers of Regional Environmental Pollution Load and Zoning Control:A Case Study of the Yangtze River Economic Belt,China 被引量:1
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作者 ZHOU Kan WU Jianxiong +1 位作者 FAN Jie LIU Hanchu 《Chinese Geographical Science》 SCIE CSCD 2022年第1期31-48,共18页
The high environmental pollution load caused by the massive pollutant emissions and the accumulation of endogenous and cross-regional pollution has become an important obstacle to the current ecological civilization c... The high environmental pollution load caused by the massive pollutant emissions and the accumulation of endogenous and cross-regional pollution has become an important obstacle to the current ecological civilization construction in the Yangtze River Economic Belt(YREB)in China.Taking the YREB as an example,by using four environmental pollutant emission indicators,including chemical oxygen demand(COD),ammonia nitrogen(NH_(3)-N),sulfur dioxide(SO_(2)),and nitrogen oxides(NO_(x)),this paper established an environmental pollution load index(EPLI)based on the entropy-based measurement.Moreover,the Spatial Durbin Model was used to quantitatively analyze the drivers and spatial effects of environmental pollution load.Finally,specific scientific references were provided for formulating environmental regulations of pollution source control in the YREB.The results showed that:1)During2011-2015,the EPLI in the YREB was reduced significantly and the environmental pollution load increased from upstream to downstream.Among them,the pollution load levels in the Upper Mainstream subbasin,Taihu Lake subbasin,and Lower Mainstream subbasin were the most prominent.2)The environmental pollution load situation in the YREB was generally stable and partially improved.High load level areas were mainly concentrated in the Yangtze River Delta Region and the provincial borders in upstream,midstream,and downstream areas.The high load level areas already formed in Chengdu and Chongqing were also the key regulatory points in the future.3)The degree of local environmental pollution load was apparently affected by the adjacent cities.The population size,industrialization level,and the fiscal decentralization not only drove the increase of the local environmental pollution load level,but also affected the adjacent areas through the spatial spillover effects.The land development intensity mainly drove the increase in the local EPLI in the YREB.While factors such as economic development level and agricultural economic share could only act on the environmental pollution load process in adjacent cities.4)According to the differentiation characteristics of drivers of each city,the YREB was divided into seven zones based on k-medoids cluster method,and targeted zoning control policy recommendations for alleviating environmental pollution load in the YREB were proposed. 展开更多
关键词 environmental pollution load drivers spatial effects Spatial Durbin Model Yangtze River Economic Belt
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The Extent and Drivers of Deforestation and Forest Degradation in Masito-Ugalla Ecosystem, Kigoma Region, Tanzania 被引量:2
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作者 John E. Makunga Salome B. Misana 《Open Journal of Forestry》 2017年第2期285-305,共21页
Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest... Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest degradation in the area, and to determine their causes. A total of 101 respondents were considered as the sample size for this study. The methods used for data collection were household questionnaire interviews, in-depth interviews, focus group discussions, analysis of satellite images and direct observation. The findings indicated that deforestation was occurring in the study area. Satellite data revealed diminished closed woodland, bushed grassland, forest and thickets between 1990 and 2014. On the contrary, settlement area, cultivated land and open woodland had increased during the same time frame. Proximate factors causing deforestation and forest degradation included agricultural expansion, wood extraction and expansion of settlement area. Underlying factors included population growth, poverty, poor levels of education, lack of employment, corruption and embezzlement of public funds by politicians and senior government officials;and high demand for fuel-wood. Biophysical drivers like incidences of unplanned wildfires and socio trigger events notably civil strife were also important. In order to minimize the problem and based on the factors augmenting deforestation and forest degradation in the Masito-Ugalla ecosystem and their coupled negative consequences, effective environmental conservation education, increased patrols, effective law enforcement and provision of alternative energy sources are necessary. 展开更多
关键词 DEFORESTATION FOREST DEGRADATION drivers of DEFORESTATION Masito-Ugalla ECOSYSTEM
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Drivers of Change in Estuarine and Coastal Marine Environments: An Overview 被引量:1
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作者 Michael J. Kennish 《Open Journal of Ecology》 2021年第3期224-239,共16页
Anthropogenic climate and non-climate drivers of change are causing significant impacts on estuarine and coastal marine environments. Climate change poses a particular threat to the structure and function of biotic co... Anthropogenic climate and non-climate drivers of change are causing significant impacts on estuarine and coastal marine environments. Climate change poses a particular threat to the structure and function of biotic communities in these environments because it acts on the most extensive temporal and spatial scales relative to other anthropogenic drivers of change. The interaction of multiple environmental drivers exacerbates degradation of ecosystem condition. Estuaries are most susceptible to climate-change mediated biotic shifts and direct anthropogenic impacts due to burgeoning human population growth and development in coastal watersheds. Multiple anthropogenic drivers of change, which often interact synergistically, alter physical, chemical, and biological characteristics. Ecological responses may be increasingly nonlinear, with cumulative effects manifested by marked changes in organism abundance, distribution, diversity, and productivity. Detrimental biotic effects in impacted coastal environments cascade up from individual organisms to population and community levels, culminating in ecosystem-level changes including reduced services. Multiple drivers of change and their impacts are increasing in estuarine and coastal marine environments with greater anthropogenic forcing in the coastal zone and global effects of climate change, creating greater challenges for environmental management and conservation programs. 展开更多
关键词 Multiple drivers Climate Change Anthropogenic Impacts Estuaries Coastal Marine Environments Management CONSERVATION RESILIENCE
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High-Level Circulating Total Calcium and Low Phosphate as Predictors of Insulin Resistance among Non-Diabetic Taxi-Motorbike Drivers Living and Working in Cotonou, Benin 被引量:2
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作者 Patrice Hodonou Avogbe Ambaliou Sanni 《Open Journal of Endocrine and Metabolic Diseases》 2022年第6期123-134,共12页
Insulin resistance (IR) is a well-recognized marker of increased cardiovascular diseases (CVDs) and type 2 diabetes (T2D) risk. Therefore, screening for IR predictors would help reduce the likelihood of progression fr... Insulin resistance (IR) is a well-recognized marker of increased cardiovascular diseases (CVDs) and type 2 diabetes (T2D) risk. Therefore, screening for IR predictors would help reduce the likelihood of progression from early stage of IR to T2D or CVDs. However, the knowledge of association between IR and circulating total calcium (CTCa) and phosphate levels among non-diabetic patients in Benin is lacking. We investigated whether CTCa and phosphate levels within the normal ranges are associated with IR risk among taxi-motorbike drivers (TMDs) living and working in Cotonou. We evaluated 134 non-diabetic TMDs (aged 22 - 59 years) based on CTCa, phosphate, glucose, fasting insulin, and IR levels. IR was assessed using the homeostatic model assessment-insulin resistance (HOMA-IR). IR was defined as the 75<sup>th</sup> percentile of HOMA-IR value. Cardiometabolic factors were analyzed by tertiles of CTCa and phosphate levels (low, middle, and high groups). Logistic regression models evaluated the relationships between IR and CTCa and phosphate levels. Our results showed that participants with high CTCa levels had the highest prevalence of IR, elevated total cholesterol and high-density lipoprotein cholesterol. In a fully adjusted model, the odd ratio (OR) of having IR comparing the highest (>2.50 mmol/L) to the lowest CTCa levels (1.23 mmol/L) and the lowest levels (<1.10 mmol/L) of phosphate was 0.28 (p = 0.037). In conclusion, our study demonstrates that elevated CTCa and low phosphate levels are significant predictors of IR in non-diabetic patients. Continuous monitoring of these markers may help identify earlier individuals at greatest IR risk. 展开更多
关键词 Blood Glucose Insulin Resistance Circulating Total Calcium Phosphate Taxi-Motorbike drivers
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Intersection Related Crash Injuries: A Study on Factors Contributing to Injury Severity among Younger and Older Drivers in Summer and Winter 被引量:1
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作者 Md Ahsanul Islam Prashant Singh 《Journal of Transportation Technologies》 2020年第4期364-379,共16页
Older drivers and younger drivers are affected differently both in summer and winter. Different factors affect each level of severity differently;some factors </span><span><span>affect a particular l... Older drivers and younger drivers are affected differently both in summer and winter. Different factors affect each level of severity differently;some factors </span><span><span>affect a particular level of injury severity differently from when the same factor is analyzed for another injury severity. The goal of this study is to identify the </span><span>factors that contribute to injury severity among older drivers (65+) and young </span><span>drivers (16</span></span><span> </span><span>-</span><span> </span><span><span>25) considering two seasons namely, summer and winter at intersections. Binary ordered probit models were used to develop four models to identify the contributing factors, two models for each season, namely winter and summer. A statistical t-test has been done to identify the statistically </span><span>significant variables @ 90% confidence interval. Based on the developed models, </span><span>in summer, three contributing factors, driving too fast condition, rear-end crashes, and followed too close are associated with younger drivers injury severity, while two contributing factors, rear-end crashes and followed too close are associated with older drivers injury severity. In winter, five factors</span></span><span>,</span><span><span> made an improper turn, E Failed to Yield Right-of-Way from Traffic Signal, rear </span><span>end (front to rear), gender like male and lighting condition like dark and dusk</span><span> light condition</span></span><span>,</span><span> are associated with younger drivers injury severity, while three factors such as made improper turn, rear-end crashes, and followed too close are associated with older drivers injury severity. Contributing factors in summer are the same for both younger and older drivers, but different in winter for both younger and older drivers. This indicates that older drivers and younger drivers are affected differently both in summer and winter. 展开更多
关键词 Older and Younger drivers Crash Severity INTERSECTION Binary Ordered Probit Model
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Visualizing Relationships between Drivers of Environmental Change and Pressures on Land-Based Ecosystems 被引量:1
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作者 Jason Jabbour Carol Hunsberger 《Natural Resources》 2014年第4期146-160,共15页
The pursuit of human needs and demands is placing more pressure on land resources than ever before. The challenge of feeding 7 billion people is increasingly competing with rising demands for materials and biofuels. D... The pursuit of human needs and demands is placing more pressure on land resources than ever before. The challenge of feeding 7 billion people is increasingly competing with rising demands for materials and biofuels. Deforestation and land degradation are among the pressing outcomes of these trends. Drivers of environmental change—including population growth, economic activity, consumption, urbanization, trade, conflict, and governance—clearly play a role in aggravating or mitigating these pressures on land. Despite advances in understanding causality in complex systems, navigating the interactions between these drivers remains a major challenge. This paper analyzes and visualizes the relationships between multiple, interacting drivers of environmental change and specific pressures on land-based ecosystems. Drawing on experience from the development of the Drivers and Land chapters of the UN Environment Programme’s Fifth Global Environment Outlook report (GEO-5), we use a series of Kiviat diagrams to illustrate the relative influence of key drivers on selected pressures on land. When individual diagrams are overlaid, patterns of influence emerge that can provide insight into where policy responses might best be targeted. We propose that, subject to some limitations, the Kiviat exercise can provide an accessible and potentially valuable “knowledge-intermediary” tool to help link science-based information to policy action. 展开更多
关键词 drivers ENVIRONMENTAL Pressure LAND Use CHANGE Integrated Assessment Science-Policy
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