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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet 被引量:1
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作者 Yumeng Liu Xianhong Meng +5 位作者 Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期47-53,共7页
Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i... Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ. 展开更多
关键词 Summer precipitation East Asian subtropical westerly jet Three River Source Region Atlantic-Eurasian teleconnection
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Assessment of the Physical Capabilities of Heart Failure Patients before and after Cardiovascular Rehabilitation: A Study of 125 Patients from West Africa, Dakar, Senegal
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作者 Aliou Alassane Ngaide Ngoné Diaba Gaye +6 位作者 Joseph Salvador Mingou Mahugbe L. C. Houenassi Aminata Mbaye Aime Mbaye Sy Fatou Aw Alassane Mbaye Abdoul Kane 《World Journal of Cardiovascular Diseases》 CAS 2024年第8期490-501,共12页
Background: Cardiac rehabilitation represents a critical therapeutic strategy for patients suffering from chronic heart failure. The physical capacity of patients with heart failure, assessed using the exercise test a... Background: Cardiac rehabilitation represents a critical therapeutic strategy for patients suffering from chronic heart failure. The physical capacity of patients with heart failure, assessed using the exercise test and the 6-minute walk test, is the measure of the patient’s overall functional ability to perform physical activities and tolerate exercise loads. The objective of this study was to assess the impact of cardiac rehabilitation on patients’ physical capabilities and to conduct a thorough comparison of data obtained via exercise testing and the 6-minute walk test before and after the rehabilitation programme. Methods: This was a descriptive and analytical cross-sectional study, conducted from 1 February 2021 to 31 June 2022. Included were heart failure patients who had participated in an outpatient cardiovascular rehabilitation programme. The collected data included anamnestic, clinical, paraclinical data, and the 6-minute walk test. Informed consent was obtained. Data analysis, word processing, and charting were performed using Microsoft Word 2016, Excel 2013, and Sphinx version 5.1.0.2. Data analysis was performed using SPSS (Statistical Package for Social Sciences) version 24.0. Any difference less than 0.05 was considered statistically significant. Results: In a Senegalese study, heart failure patients undergoing rehabilitation in a cardiac unit represented 45.59% of all cases, with a prevalence rate of 3.21%. The average participant was 57.97 years old, with those aged 61 to 70 forming the largest group (35.5%). The study noted a male predominance (sex ratio of 2.1) and identified dyslipidaemia (80.6%) and sedentarism (71%), as prevalent cardiovascular risk factors. All participants initially suffered from NYHA stage 2 or 3 dyspnoea, yet 80.65% showed no symptoms following rehabilitation. Significant improvements were recorded in resting heart rate (from 79 to 67 bpm), and the 6-minute walk test distance (from 328 m to 470 m). Enhanced exercise tolerance and walking test outcomes were particularly notable in patients with LVEF ≥ 50%, women, non-obese individuals, those initially walking less than 300 m, achieving more than 3 METs, and non-smokers. Conclusion: The findings underscore the effectiveness of cardiovascular rehabilitation in improving symptoms, physical capability, and overall quality of life for heart failure patients in Senegal. 展开更多
关键词 Cardiovascular Rehabilitation Heart Failure Physical Capabilities Quality of Life Improvement west Africa
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Westerlies Affecting the Seasonal Variation of Water Vapor Transport over the Tibetan Plateau Induced by Tropical Cyclones in the Bay of Bengal
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作者 Xiaoli ZHOU Wen ZHOU +3 位作者 Dongxiao WANG Qiang XIE Lei YANG Qihua PENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期881-893,共13页
This study investigates the activity of tropical cyclones(TCs)in the Bay of Bengal(BOB)from 1979 to 2018 to discover the mechanism affecting the contribution rate to the meridional moisture budget anomaly(MMBA)over th... This study investigates the activity of tropical cyclones(TCs)in the Bay of Bengal(BOB)from 1979 to 2018 to discover the mechanism affecting the contribution rate to the meridional moisture budget anomaly(MMBA)over the southern boundary of the Tibetan Plateau(SBTP).May and October–December are the bimodal phases of BOB TC frequency,which decreases month by month from October to December and is relatively low in May.However,the contribution rate to the MMBA is the highest in May.The seasonal variation in the meridional position of the westerlies is the key factor affecting the contribution rate.The relatively southern(northern)position of the westerlies in November and December(May)results in a lower(higher)contribution rate to the MMBA.This mechanism is confirmed by the momentum equation.When water vapor enters the westerlies near the trough line,the resultant meridional acceleration is directed north.It follows that the farther north the trough is,and the farther north the water vapor can be transported.When water vapor enters the westerlies from the area near the ridge line,for Type-T(Type-R)TCs,water vapor enters the westerlies downstream of the trough(ridge).Consequently,the direction of the resultant meridional acceleration is directed south and the resultant zonal acceleration is directed east(west),which is not conducive to the northward transport of water vapor.This is especially the case if the trough or ridge is relatively south,as the water vapor may not cross the SBTP. 展开更多
关键词 tropical cyclone Tibetan Plateau Bay of Bengal moisture budget weste
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Effects of Natural Processes on Sea Level Change along the West African Coastline
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作者 Anoumou R. Tano Sandrine Djakouré +6 位作者 Kouamé J. Koffi Yves Kouadio Yao Tchetche Donatus B. Angnuureng Angora Aman François-Xavier B. D. Bouo Appeaning Addo 《Open Journal of Marine Science》 2024年第4期78-95,共18页
Coastal hazards induced by meteo-marine forcing are exacerbated by sea level change along the West African coastline. Changes in sea level are induced by ocean processes such as ocean heat content and river discharge.... Coastal hazards induced by meteo-marine forcing are exacerbated by sea level change along the West African coastline. Changes in sea level are induced by ocean processes such as ocean heat content and river discharge. However, although these processes control largely change in sea level, they remain poorly understood. This study analyzes changes in ocean heat content, river discharge, and sea level and establishes an interconnection between these parameters using several statistical methods over the 1993-2021 period. Results showed a significant correlation between sea level and ocean heat content at 2000 m depth. The yearly minimum value appears in July from Cote d’Ivoire to Benin, whilst this value appears in June in Nigeria. The temporal variability of ocean heat content, river discharge and sea level along the West African coastline exhibits three or four periods interrupted by some breakpoints with unequal duration. The results indicate that the 1993-2000 period was dominated by an increasing ocean heat content along the coastline, while the period after the 2000s exhibits mostly a decreasing trend. Positive and negative trends characterized river discharge and sea level along this coastline. The result of multiple linear regression between sea level, river discharge and ocean heat content is a good approximation of sea level trend along the West African coastline. The results of this study could be used to predict future sea level trends along the coast. 展开更多
关键词 Coastal Sea Level River Discharge Heat Content west African Coast
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Socioenvironmental Drivers of Farmers’ Perceptions of Climate Change Risk in Agroforestry Parklands of West Atacora in Benin (West Africa)
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作者 Amos Baninwain Nambima Thierry Dèhouégnon Houehanou +3 位作者 Narcisse Yehouenou Dowo Michée Adjacou Abdul Sodick Alassiri Gérard Gouwakinnou 《Open Journal of Ecology》 2024年第1期54-65,共12页
Throughout the world, climate change is threatening the human population. In West Africa, smallholder farmers in indigenous agricultural societies typically hold considerable knowledge. Therefore, this study was condu... Throughout the world, climate change is threatening the human population. In West Africa, smallholder farmers in indigenous agricultural societies typically hold considerable knowledge. Therefore, this study was conducted in West Atacora of Benin Republic to assess the drivers of farmers’ perceptions of climate change risk. We used a random sampling technique to select 360 households’ heads who were interviewed regarding different climate change risks perception. Binomial logistic regression was used to assess the drivers of farmers’ perceptions of climate change risks. The results showed that the farmers in drier areas had a higher perception of the global risk of climate change than those in humid areas. The same trend was observed for the seven different individual’s climate change risk investigated. The study identified also membership of farm organizations as main sociodemographic characteristic that explains farmers’ perception of climate change risk perception. These findings are helpful tools to sensitize the local people on climate change risk and cope with the risk in agricultural lands. 展开更多
关键词 Climate Change Risk Local Ecological Knowledge Socio-Demographic Characteristics BENIN west Africa
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Offshore high-grade limemud resources of west coast of India:Economic potential and industrial applications
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作者 Anil Kumar Adukadukkam Rachna Pillai Mamatha Puthiyathara Kanakamma 《Deep Underground Science and Engineering》 2024年第2期163-170,共8页
Limestone is one of the essential raw materials in the cement,paint,steel,ceramic,glass,chemical,pharmaceutical,paper,and fertilizer industries.In India,only 8%of the limestone resources are placed under the reserve c... Limestone is one of the essential raw materials in the cement,paint,steel,ceramic,glass,chemical,pharmaceutical,paper,and fertilizer industries.In India,only 8%of the limestone resources are placed under the reserve category,of which 97%is of cement grade.Thus,India depends on imports to bridge the demand‐supply gap of steel,blast furnace,and chemical‐grade limestone.Efforts of Geological Survey of India(GSI)to locate alternate sources for limestone led to the discovery of enormous quantities of carbonate minerals called limemud from the continental shelf margin of the west coast of India.GSI carried out systematic studies to explore the nature of the disposition,quality,quantity,and suitability of the offshore limemud for various industrial applications.A preliminary estimate of resources using high‐resolution subbottom profiling and sediment core sample studies established the occurrence of more than 172 billion tonnes of high‐grade(The content of CaCO3 is greater than 80 wt%)limemud in 0.4–28.0m thick stratified sediment layers spread over an area of 18000 km2.Chemical,physical,mineralogical,beneficiation,and agglomeration studies found the offshore limemud as a potential replacement for limestone in the cement,filler,blast furnace,steel melting shop,lime production,paint,and Grade‐I steel industries.An assessment of mining and transportation costs indicates that the offshore limemud(USD 5–6/ton)is more cost‐effective than that imported from other countries(USD16‐18/ton).With several advantageous factors like low impurity,mode of occurrence in overburden‐free stratified form,fine‐grained slurry nature,and shallow water depth,sustainable mining of offshore limemud could be a future reality with controllable technological,economic,and environmental challenges. 展开更多
关键词 BENEFICIATION industrial grade offshore limemud west coast of India
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Endoscopic submucosal dissection for early gastric cancer:A major challenge for the west
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作者 Francisco Schlottmann 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期1965-1968,共4页
Gastric cancer(GC)is the 5th most common cancer and the 3rd most common cause of cancer mortality worldwide.Two main endoscopic resective techniques exist for early GC(EGC):Endoscopic mucosal resection(EMR)and endosco... Gastric cancer(GC)is the 5th most common cancer and the 3rd most common cause of cancer mortality worldwide.Two main endoscopic resective techniques exist for early GC(EGC):Endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD).ESD has been widely embraced in the last decade because it allows radical en bloc resections and is associated with better outcomes,as compared to EMR.However,the lack of training opportunities and flat learning curve due to low volume of EGC cases represent major obstacles to obtain proficiency on ESD in the West.As this procedure is highly efficient for the treatment of EGC,dedicated training programs with a stepwise approach and updated guidelines for ESD embracement are needed in Western countries. 展开更多
关键词 Gastric cancer Early gastric cancer ENDOSCOPY west Training
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Geology and S-Pb isotope geochemistry of the Hatu gold deposit in West Junggar,NW China:Insights into ore genesis and metal source
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作者 Shen Han Zhenju Zhou +6 位作者 Xiaohua Deng Yanshuang Wu Xi Chen Abulimiti Aibai Yong Wang Xiaoyu Jia Yanjing Chen 《Acta Geochimica》 EI CAS CSCD 2024年第6期1205-1222,共18页
The Hatu gold deposit is the largest historical gold producer of the West Junggar,western China,with an Au reserve of about 62 t.The orebodies were controlled by NE-,EW-,and NW-trending subsidiary faults associated wi... The Hatu gold deposit is the largest historical gold producer of the West Junggar,western China,with an Au reserve of about 62 t.The orebodies were controlled by NE-,EW-,and NW-trending subsidiary faults associated with the Anqi fault.This deposit exhibits characteristics typical of a fault-controlled lode system,and the orebodies consist of auriferous quartz veins and altered wall rocks within Early Carboniferous volcano-sedimentary rocks.Three stages of mineralization have been identified in the Hatu gold deposit:the early pyrite-albite-quartz stage,the middle polymetallic sulfides-ankerite-quartz stage,and late quartz-calcite stage.The sulfur isotopic values of pyrite and arsenopyrite vary in a narrow range from-0.8‰to1.3‰and an average of 0.4‰,the near-zeroδ~(34)S values implicate the thorough homogenization of the sulfur isotopes during the metamorphic dehydration of the Early Carboniferous volcano-sedimentary rocks.Lead isotopic results of pyrite and arsenopyrite(^(206)Pb/^(204)Pb=17.889-18.447,^(207)Pb/^(204)Pb=15.492-15.571,^(208)Pb/^(204)Pb=37.802-38.113)are clustered between orogenic and mantle/upper crust lines,indicating that the lead was mainly sourced from the hostrocks within the Early Carboniferous Tailegula Formation.The characteristics of S and Pb isotopes suggest that the ore-forming metals of the Hatu orogenic gold deposit are of metamorphogenic origin,associated with the continental collision between the Yili-Kazakhstan and Siberian plates during the Late Carboniferous. 展开更多
关键词 Hatu gold deposit Sulfur isotope Lead isotope Orogenic gold deposit west Junggar
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Architecture and exploration target areas of the Senegal Basin,West Africa
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作者 Naxin Tian Gaokui Wu +3 位作者 Min Gao Yue Gong Dapeng Wang Zhipeng Liu 《Energy Geoscience》 EI 2024年第4期174-186,共13页
The recent discovery of large oil and gas fields in the deep-water of the Senegal Basin has drawn global attention.Despite this,several exploration wells in this area fail,which can be primarily contributed to a lack ... The recent discovery of large oil and gas fields in the deep-water of the Senegal Basin has drawn global attention.Despite this,several exploration wells in this area fail,which can be primarily contributed to a lack of understanding of the basin's structures and hydrocarbon accumulation conditions.This study examines these characteristics utilizing gravity,seismic and drilling data,and finally makes a comparison with the Cote d’Ivoire Basin,a typical transform margin basin in the South Atlantic.The results suggest that the Senegal Basin,influenced by multiple transform faults and a weak Paleozoic basement,experienced three evolutionary stages:rifting,transitional,and drifting.Each stage contributed to the development of distinct depositional sequences-syn-rift sequences,sag sequences,and continental margin sequences,respectively.The Triassic-Early Jurassic rifting stage predominantly formed continental deposits,like fluvial,lacustrine,and deltaic deposits,in the syn-rift sequences.The Middle-Late Jurassic transitional stage,influenced by transform faults,witnessed the formation of marginal ridges or submarine uplift zones.These zones,in conjunction with landward high terrains,formed a restricted environment promoting the development of source rocks in the sag sequences.During the drifting stage,three types of reservoirs,namely platform carbonate rocks,deltas,and slope-floor fans were formed.Notably,large-scale hydrocarbon reservoirs have been found in the deltas and the slope-floor fans both in the Senegal Basin and the Cote d’Ivoire Basin.The Upper Jurassic-Aptian platforms exhibit thick carbonate rocks and organic reefs on their edges,suggesting substantial potential for hydrocarbon exploration in the Senegal Basin. 展开更多
关键词 Transform-extensional passive continental margin Basin architecture Accumulation model Senegal Basin west Africa
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Use of Topical Complementary and Alternative Medicines (CAM) in Diabetic Septic Foot Disease in Makkah Region, Western of Saudi Arabia, an Exploratory Study
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作者 Mohamed Elamin Salih Hatim Alrizqi +5 位作者 Mohammed Hussain Abdullah Alshumrani Ismail Alhasani Ali Alkhamisi Hamzah Alsayed Fahad Alqarni 《Journal of Biosciences and Medicines》 2024年第3期245-258,共14页
Diabetes is a chronic condition that is significantly impacted daily by environment. At least one in five Saudis, suffer from diabetes. “Diabetes is a pandemic of unprecedented magnitude spiraling out of control” (B... Diabetes is a chronic condition that is significantly impacted daily by environment. At least one in five Saudis, suffer from diabetes. “Diabetes is a pandemic of unprecedented magnitude spiraling out of control” (Boulton). Saudi Arabia ranks the second highest in the Middle East, and is the seventh in the world for the prevalence of diabetes (WHO). Diabetes mellitus (DM) has been found to be related to high mortality, morbidity accompanied by poor general health and lower quality of life. Current Saudi diabetes patients’ behaviors, practices, and beliefs regarding foot health problems such as ulcers, are not well investigated. Diabetic patients frequently utilize natural remedies and Herbs for self-medication as a part of complementary and alternative Medicine. Aim of study: To explore the widespread use of the alternative remedies in the local communities of the Western Saudi Arabia, the drives behind using and to focus on the potential adverse effects following their usage. Method: A descriptive, cross-sectional study of 386 diabetic patients with feet problems in Makkah Region, West of Saudi Arabia during the period April - June 2023. Results: Out of the 531 participants, only 386 participants reported diabetic foot disorder (DFD). Most of the participant were above 65 years of age group (24.61 %). Male (52.08%) more than female (47.92%) in the research group. All of the participants had diabetic foot disorders at least once. The prevalence of complementary and alternative medicines (CAM) use among them was 67.88%, as solitary or in combination with hospital medicines. Honey headed the list followed by myrrh and black seeds. Acquaintances advice (59.54%) was the most reason for using the alternative medicine. 60.30% of Diabetic foot patient complained of adverse effects during CAM remedies use. Conclusion: Consumption of CAM remedies among diabetic patients for Diabetic Foot Disorder (DFD) is common. Honey headed the list followed by myrrh and black seeds. Additional wide-scale research is required to establish their actual efficacy, safety and potential adverse out-comes and to generalize the outcomes. 展开更多
关键词 Diabetic Foot Ulcer Diabetes Complementary and Alternative Medicine CAM west of Saudi Arabia
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Isolated Hyperacute T-Waves in West Nile Encephalitis Indicating Atypical Variant of Stress-Induced Cardiomyopathy
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作者 Soomal Rafique Nadeem Khan Momin Siddique 《Journal of Biosciences and Medicines》 2024年第2期303-310,共8页
Several cardiac outcomes have been reported with West Nile-encephalitis;however, the underlying pathophysiology remains complex. We present a 42-year-old female, with multiple sclerosis, whose neurological symptoms an... Several cardiac outcomes have been reported with West Nile-encephalitis;however, the underlying pathophysiology remains complex. We present a 42-year-old female, with multiple sclerosis, whose neurological symptoms and respiratory decline were finally explained by the diagnosis of West Nile-encephalitis. During her admission, the isolated peaked T-waves indicated the underlying stress-induced cardiomyopathy. The absence of all other causes of hyperacute T-waves, their subsequent resolution with the resolution of infection and improvement in wall motion abnormalities, further supported the association. This case highlights the importance of considering hyperacute T-waves in an approach towards the diagnosis of WNV-encephalitis related atypical variant of stress-induced cardiomyopathy. 展开更多
关键词 west Nile Virus encephalitis WNV Hyperacute T-Waves Takotsubo Cardiomyopathy Atypical/Inverted Variant of Stress-Induced Cardiomyopathy CMP
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A systematic review of climate change impacts,adaptation strategies,and policy development in West Africa
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作者 Camillus Abawiera WONGNAA Alex Amoah SEYRAM Suresh BABU 《Regional Sustainability》 2024年第2期13-25,共13页
Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study ... Climate change studies are diverse with no single study giving a comprehensive review of climate change impacts,adaptation strategies,and policy development in West Africa.The unavailability of an all-inclusive study to serve as a guide for practitioners affects the effectiveness of climate change adaptation strategies proposed and adopted in the West African sub-region.The purpose of this study was to review the impacts of climate change risks on the crop,fishery,and livestock sectors,as well as the climate change adaptation strategies and climate-related policies aimed at helping to build resilient agricultural production systems in West Africa.The review process followed a series of rigorous stages until the final selection of 56 articles published from 2009 to 2023.Generally,the results highlighted the adverse effects of climate change risks on food security.We found a continuous decline in food crop production.Additionally,the livestock sector experienced morbidity and mortality,as well as reduction in meat and milk production.The fishery sector recorded loss of fingerlings,reduction in fish stocks,and destruction of mariculture and aquaculture.In West Africa,climate-smart agriculture technologies,physical protection of fishing,and inclusion of gender perspectives in programs appear to be the major adaptation strategies.The study therefore recommends the inclusion of ecosystem and biodiversity restoration,weather insurance,replacement of unsafe vessels,and strengthening gender equality in all climate change mitigation programs,as these will help to secure enough food for present and future generations. 展开更多
关键词 Climate change Climate extreme events Food security Adaptation strategies Climate-smart AGRICULTURE west Africa
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Petroleum geological characteristics and exploration targets of the oil-rich sags in the Central and West African Rift System
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作者 DOU Lirong SHI Zhongsheng +1 位作者 PANG Wenzhu MA Feng 《Petroleum Exploration and Development》 SCIE 2024年第1期1-14,共14页
Based on seismic,drilling,and source rock analysis data,the petroleum geological characteristics and future exploration direction of the oil-rich sags in the Central and West African Rift System(CWARS)are discussed.Th... Based on seismic,drilling,and source rock analysis data,the petroleum geological characteristics and future exploration direction of the oil-rich sags in the Central and West African Rift System(CWARS)are discussed.The study shows that the Central African Rift System mainly develops high-quality lacustrine source rocks in the Lower Cretaceous,and the West African Rift System mainly develops high-quality terrigenous organic matter-rich marine source rocks in the Upper Cretaceous,and the two types of source rocks provide a material basis for the enrichment of oil and gas in the CWARS.Multiple sets of reservoir rocks including fractured basement and three sets of regional cap rocks in the Lower Cretaceous,the Upper Cretaceous,and the Paleogene are developed in the CWARS.Since the Late Mesozoic,due to the geodynamic factors including the dextral strike-slip movement of the Central African Shear Zone,the basins in different directions of the CWARS differ in terms of rifting stages,intervals of regional cap rocks,trap types and accumulation models.The NE-SW trending basins have mainly preserved one stage of rifting in the Early Cretaceous,with regional cap rocks developed in the Lower Cretaceous strata,forming traps of reverse anticlines,flower-shaped structures and basement buried hill,and two types of hydrocarbon accumulation models of"source and reservoir in the same formation,and accumulation inside source rocks"and"up-source and down-reservoir,and accumulation below source rocks".The NW–SE basins are characterized by multiple rifting stages superimposition,with the development of regional cap rocks in the Upper Cretaceous and Paleogene,forming traps of draping anticlines,faulted anticlines,antithetic fault blocks and the accumulation model of"down-source and up-reservoir,and accumulation above source rocks".The combination of reservoir and cap rocks inside source rocks of basins with multiple superimposed rifting stages,as well as the lithologic reservoirs and the shale oil inside source rocks of strong inversion basins are important fields for future exploration in basins of the CWARS. 展开更多
关键词 source rock regional cap rock trap type accumulation model oil-rich sag Central African Shear Zone Central and west African Rift System
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Diagnosis of West Nile virus infections:Evaluation of different laboratory methods
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作者 Tatjana Vilibic-Cavlek Maja Bogdanic +11 位作者 Vladimir Savic Zeljka Hruskar Ljubo Barbic Vladimir Stevanovic Ljiljana Antolasic Ljiljana Milasincic Dario Sabadi Gorana Miletic Ivona Coric Anna Mrzljak Eddy Listes Giovanni Savini 《World Journal of Virology》 2024年第4期51-61,共11页
BACKGROUND The diagnosis of West Nile virus(WNV)is challenging due to short-term and low-level viremia,flavivirus cross-reactivity,and long immunoglobulin M(IgM)persistence.AIM To evaluate different methods for WNV de... BACKGROUND The diagnosis of West Nile virus(WNV)is challenging due to short-term and low-level viremia,flavivirus cross-reactivity,and long immunoglobulin M(IgM)persistence.AIM To evaluate different methods for WNV detection[reverse transcription-polymerase chain reaction(RT-PCR),IgM/IgG antibodies,IgG avidity]in serum,cerebrospinal fluid(CSF),and urine samples of patients with confirmed WNV infection.METHODS The study included patients with confirmed WNV neuroinvasive infection(n=62),asymptomatic WNV seropositive individuals(n=22),and individuals with false-positive WNV IgM antibodies(n=30).WNV RNA was detected using RT-PCR.A commercial ELISA was used to detect WNV IgM/IgG antibodies with confirmation of cross-reactive samples using a virus neutralization test(VNT).IgG-positive samples were tested for IgG avidity.RESULTS The WNV-RNA detection rates were significantly higher in the urine(54.5%)/serum(46.4%)than in CSF(32.2%).According to the sampling time,the WNV-RNA detection rates in urine collected within 7 days/8-14/≥15 days were 29.4/66.6/62.5%(P=0.042).However,these differences were not observed in the CSF.The median RT-PCR cycle threshold values were significantly lower in urine(32.5,IQR=28-34)than in CSF(34.5,IQR=33-36).The frequency of positive WNV IgM and IgG significantly differed according to the sampling time in serum but not in CSF.Positive IgM/IgG antibodies were detected in 84.3/9.3%of serum samples collected within 7 days,100/71.1%of samples collected 8-14,and 100%samples collected after≥15 days.Recent WNV infection was confirmed by low/borderline avidity index(AI)in 13.6%of asymptomatic individuals.A correlation between ELISA and AI was strong negative for IgM and strong positive for IgG.No significant correlation between ELISA IgG and VNT was found.CONCLUSION The frequency of WNV RNA and antibody detection depends on the sampling time and type of clinical samples.IgG avidity could differentiate recent WNV infections from long-persisting IgM antibodies. 展开更多
关键词 west Nile virus Reverse transcription-polymerase chain reaction SEROLOGY IgG avidity CROSS-REACTIVITY
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Control of the Dust Vertical Distribution over Western Africa by Convection and Scavenging
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作者 H.Senghor R.Pilon +7 位作者 B.Diallo J.Escribano F.Hourdin J.Y.Grandpeix O.Boucher M.Gueye A.T.Gaye E.Machu 《Journal of Atmospheric Science Research》 2024年第1期19-39,共21页
Saharan dust represents more than 50%of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale.Previous studies on dust vertica... Saharan dust represents more than 50%of the total desert dust emitted around the globe and its radiative effect significantly affects the atmospheric circulation at a continental scale.Previous studies on dust vertical distribution and the Saharan Air Layer(SAL)showed some shortcomings that could be attributed to imperfect representation of the effects of deep convection and scavenging.The authors investigate here the role of deep convective transport and scavenging on the vertical distribution of mineral dust over Western Africa.Using multi-year(2006-2010)simulations performed with the variable-resolution(zoomed)version of the LMDZ climate model.Simulations are compared with aerosol amounts recorded by the Aerosol Robotic Network(AERONET)and with vertical profiles of the Cloud-Aerosol Lidar with Orthogonal Polarization(CALIOP)measurements.LMDZ allows a thorough examination of the respective roles of deep convective transport,convective and stratiform scavenging,boundary layer transport,and advection processes on the vertical mineral dust distribution over Western Africa.The comparison of simulated dust Aerosol Optical Depth(AOD)and distribution with measurements suggest that scavenging in deep convection and subsequent re-evaporation of dusty rainfall in the lower troposphere are critical processes for explaining the vertical distribution of desert dust.These processes play a key role in maintaining a well-defined dust layer with a sharp transition at the top of the SAL and in establishing the seasonal cycle of dust distribution.This vertical distribution is further reshaped offshore in the Inter-Tropical Convergence Zone(ITCZ)over the Atlantic Ocean by marine boundary layer turbulent and convective transport and wet deposition at the surface. 展开更多
关键词 DUST Vertical distribution SAHARA SAHEL west Africa Climate model CONVECTION SCAVENGING ITCZ
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Influence of Continental Atmospheric Forcing on the Decadal Variability of the West African Monsoon
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作者 Adjoua Moïse Landry Famien Sandrine Djakouré +3 位作者 Bi Tra Jean Claude Youan Serge Janicot Abé Delfin Ochou Arona Diedhiou 《Atmospheric and Climate Sciences》 2024年第1期1-28,共28页
The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability... The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability involves the role of atmospheric dynamics, linked in particular to the Saharan Heat Low (SHL). This article addresses this question by comparing the sets of preindustrial control and historical simulation data from climate models carried out in the framework of the CMIP5 project and observations data over the 20<sup>th</sup> century. Through multivariate statistical analyses, it was established that decadal modes of ocean variability and decadal variability of Saharan atmospheric dynamics significantly influence decadal variability of monsoon precipitation. These results also suggest the existence of external anthropogenic forcing, which is superimposed on the decadal natural variability inducing an intensification of the signal in the historical simulations compared to preindustrial control simulations. We have also shown that decadal rainfall variability in the Sahel, once the influence of oceanic modes has been eliminated, appears to be driven mainly by the activity of the Arabian Heat Low (AHL) in the central Sahel, and by the structure of the meridional temperature gradient over the inter-tropical Atlantic in the western Sahel. 展开更多
关键词 Influence of Continental Atmospheric Forcing on the Decadal Variability of the west African Monsoon
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风能模拟系统WEST在中国风能数值模拟中的应用 被引量:42
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作者 张德 朱蓉 +2 位作者 罗勇 俞卫 王澄海 《高原气象》 CSCD 北大核心 2008年第1期202-207,共6页
利用加拿大风能资源数值模拟系统(WEST)进行中国风能资源的模拟,得到了水平分辨率5km、低空垂直分辨率10 m的中国风能分布图谱。将模拟结果与气象台站观测资料进行了对比分析,结果表明,WEST在中国中东部海拔较低地区的模拟能力较好,平... 利用加拿大风能资源数值模拟系统(WEST)进行中国风能资源的模拟,得到了水平分辨率5km、低空垂直分辨率10 m的中国风能分布图谱。将模拟结果与气象台站观测资料进行了对比分析,结果表明,WEST在中国中东部海拔较低地区的模拟能力较好,平均相对误差<20%,但对于中国西部高原的模拟结果不理想,相对误差达到了60%以上,说明WEST系统对中国西部高原的模拟能力还需提高。应从其大尺度气候背景场分类和中尺度模型大气边界层物理过程参数化方面进行本地化改进,使之能更好地应用于中国风能资源评估工作。 展开更多
关键词 west 风能资源 数值模拟
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WEST仿真软件在污水处理中的应用研究 被引量:15
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作者 揭大林 操家顺 +1 位作者 花月 孙大伟 《环境工程学报》 CAS CSCD 北大核心 2007年第3期138-141,共4页
介绍了活性污泥系统仿真软件WEST的模型机理及其建模的过程,通过实例分析了WEST软件在无锡城北污水处理厂中模拟应用,结果表明,模拟值能较好地反映污水处理厂实际运行状况,并分析讨论了模拟过程中应注意的几点事项。
关键词 活性污泥模型 west软件 污水处理
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风能资源数值模拟系统WEST在新疆地区的应用 被引量:8
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作者 张德 刘秋锋 +2 位作者 朱蓉 罗勇 李泽椿 《沙漠与绿洲气象》 2007年第1期16-19,共4页
利用加拿大风能资源数值模拟系统WEST进行新疆风能资源的模拟,得到了水平分辨率5km、低空垂直分辨率10m的新疆风能分布图谱,并将模拟结果与气象台站观测资料进行了对比分析,说明了WEST对于新疆大部分地区的模拟能力较好,但对新疆南部盆... 利用加拿大风能资源数值模拟系统WEST进行新疆风能资源的模拟,得到了水平分辨率5km、低空垂直分辨率10m的新疆风能分布图谱,并将模拟结果与气象台站观测资料进行了对比分析,说明了WEST对于新疆大部分地区的模拟能力较好,但对新疆南部盆地高原边缘地区的模拟能力还需提高。应从其大尺度气候背景场分类和中尺度模型大气边界层物理过程参数化方面进行本地化改进,使之能更好的应用于中国风能资源评估工作。 展开更多
关键词 风能资源 数值模拟 west
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31例West综合征临床与脑电图分析 被引量:4
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作者 王云 梁东 贾飞勇 《中国妇幼保健》 CAS 北大核心 2007年第3期361-362,共2页
目的:探讨31例W est综合征患儿的临床与脑电图改变。方法:对临床表现符合或疑似W est综合征患儿进行常规脑电图检测,对于未发现癫痫波形或发现疑似癫痫波形的病例进行24 h动态脑电图检测。结果:31例患儿脑电图均为异常:高峰失律(74.20%)... 目的:探讨31例W est综合征患儿的临床与脑电图改变。方法:对临床表现符合或疑似W est综合征患儿进行常规脑电图检测,对于未发现癫痫波形或发现疑似癫痫波形的病例进行24 h动态脑电图检测。结果:31例患儿脑电图均为异常:高峰失律(74.20%),变异性高峰失律(6.45%)或其它形式异常脑电图(19.30%)。结论:婴儿痉挛症除典型发作形式和精神运动发育障碍(本组病例78.20%)外,具有特异性脑电图改变(高峰失律)。脑电图是确诊婴儿痉挛症的重要依据。 展开更多
关键词 west综合征 临床表现 脑电图
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