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Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases
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作者 Yating ZHAO Ming XUE +2 位作者 Jing JIANG Xiao-Ming HU Anning HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期619-638,共20页
Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss pos... Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are available.The RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of precipitation.This dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the simulation.Inaccuracy in reproducing large-scale circulation and environmental conditions is another contributing factor.The too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great Plains.The simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as well.Therefore,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios. 展开更多
关键词 NARCCAP Central united states PRECIPITATION low-level jet large-scale environment diurnal variation
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Characteristics of patients with Wilson disease in the United States: An insurance claims database study
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作者 Thomas Daniel-Robin Pradeep Kumar +1 位作者 Bernard Benichou Jean-Philippe Combal 《World Journal of Hepatology》 2024年第5期791-799,共9页
BACKGROUND Wilson disease(WD)is a progressive,potentially fatal degenerative disease affecting the liver and central nervous system.Given its low prevalence,collecting data on large cohorts of patients with WD is chal... BACKGROUND Wilson disease(WD)is a progressive,potentially fatal degenerative disease affecting the liver and central nervous system.Given its low prevalence,collecting data on large cohorts of patients with WD is challenging.Comprehensive insur-ance claims databases provide powerful tools to collect retrospective data on large numbers of patients with rare diseases.AIM To describe patients with WD in the United States,their treatment and clinical outcome,using a large insurance claims database.METHODS This retrospective,longitudinal study was performed in the Clarivate Real-World Data Product database.All patients with≥2 claims associated with an Interna-tional Classification of Diseases 10(ICD-10)diagnostic code for WD(E83.01)between 2016 and 2021 were included and followed until death or study end.Patients were divided into two groups by whether or not they were documented to have received a specific treatment for WD.Clinical manifestations,hospital-isations,liver transplantation and death were documented.RESULTS Overall,5376 patients with an ICD-10 diagnostic code for WD were identified.The mean age at inclusion was 41.2 years and 52.0%were men.A specific WD treatment was documented for 885 patients(15.1%),although the number of patients taking zinc salts may be underestimated due to over the counter purchase.At inclusion,the mean age of patients with a documented treatment was 36.6±17.8 years vs 42.2±19.6 years in those without a documented treatment.During follow-up,273 patients(5.1%)died.Compared with the American general population,the standardised mortality ratio was 2.19.The proportion of patients with a documented WD-specific treatment who died during follow-up was 4.0%and the mean age at death 52.7 years.CONCLUSION Patients treated for WD in the United States had an excess early mortality compared with the American population.These findings indicate that there is a significant unmet need for effective treatment for WD in the United States. 展开更多
关键词 Wilson disease MORTALITY Treatment Copper chelators Zinc acetate united states
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Coping with the Impact of Climate Change: A Dive into Precision Agriculture in the United States
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作者 Oluwaseun Ibukun Kehinde Oke Olawale Oluwafemi 《Journal of Agricultural Chemistry and Environment》 2024年第2期208-222,共15页
With the continued increase in the number of people that are food insecure globally, which could be increasing because of the ongoing Ukraine-Russia war, leading to reduction in international agribusinesses, coupled w... With the continued increase in the number of people that are food insecure globally, which could be increasing because of the ongoing Ukraine-Russia war, leading to reduction in international agribusinesses, coupled with drastic climate change exacerbating the problem of food insecurity, there is a constant need to come up with innovative approaches to solve this global issue. In this article, we articulated how precision agriculture can be a tool for ensuring food security in the United States. This study aims to reiterate the significance of precision agriculture in solving global food insecurity. 展开更多
关键词 united states Food Insecurity Precision Agriculture Positioning Systems Climate Change
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Evolution and impacts of the United States’Arctic strategy and China’s responses 被引量:1
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作者 LIAO Junjie PAN Min 《Advances in Polar Science》 CSCD 2023年第2期144-152,共9页
On 7 October,2022,the Biden administration released an updated version of the National Strategy for the Arctic Region based on new developments in the Arctic region and global affairs.This strategy emphasizes traditio... On 7 October,2022,the Biden administration released an updated version of the National Strategy for the Arctic Region based on new developments in the Arctic region and global affairs.This strategy emphasizes traditional security issues in the Arctic,attaches great importance to climate governance in the region,and advocates for restoring American leadership through international cooperation.In view of the strong influence of the United States(U.S.)in the Arctic region,the changes of the U.S.Arctic strategy will inevitably have an impact on China’s scientific researchrights,economic interests,and governance rights in the Arctic region.To respond to the new situation brought about by the changes in the U.S.Arctic strategy,China should take the initiative to maintain positive relationships with all Arctic countries,and continue its active participation in Arctic affairs. 展开更多
关键词 the united states’Arctic strategy Arctic security Arctic governance
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Strategic Planning for Drug Regulatory Science in the United States and Its Enlightenments to China
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作者 Chang Yingnan Gong Jingran +1 位作者 Chang Senhao Chen Yuwen 《Asian Journal of Social Pharmacy》 2023年第2期91-97,共7页
Objective To study the strategic planning of drug regulatory science,the effectiveness and role of policy implementation in the United States so as to gain insights and make suggestions for further improving the strat... Objective To study the strategic planning of drug regulatory science,the effectiveness and role of policy implementation in the United States so as to gain insights and make suggestions for further improving the strategic planning of drug regulatory science in China.Methods Literature research method and comparative research method were used to compare and analyze the strategic planning of regulatory science in China and the United States.Results and Conclusion Drawing on the US experience,China should set goals based on mission and vision and identify problems,knowledge gaps,and key areas,then concrete measures can be taken to advance regulatory science. 展开更多
关键词 the united states DRUG regulatory science strategic planning
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A Comparative Study of the Value Orientations of Foreign Language Education Policies in China and the United States in the 21st Century
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作者 曹迪 《海外英语》 2021年第12期278-280,共3页
Since the 21 st century, both Chinese Mainland and the United States have formulated foreign language education policiesbased on their national needs. This paper makes a comparative study of the value orientations of ... Since the 21 st century, both Chinese Mainland and the United States have formulated foreign language education policiesbased on their national needs. This paper makes a comparative study of the value orientations of foreign language education poli-cies in Chinese Mainland and the United States in the 21 st century and finds that both China and the United States have regardedtheir national interests as the essential value orientation of their foreign language education policies. To be specific,the core valueorientation of foreign language education policies in China is to enhance its cultural soft power.In contrast,the core value orienta-tion of foreign language education policies in the United States is to safeguard its national security. Through the comparison of thedifferent value orientations of foreign language education policies of the two countries, the paper provides some reference for the for-eign language education policy-making in Chinese Mainland. 展开更多
关键词 Foreign language education policies in China's Mainland Foreign language education policies in the united states Value orientations
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Dr. Ralph Coan: a hero in establishing acupuncture as a profession in the United States 被引量:5
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作者 Arthur Yin Fan Ziyi Fan 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第1期39-44,共6页
1 Introduction Dr. Ralph Coan is not well known to the general public. Originally, we had wanted to interview him as he was the medical director of the first acupuncture center in the United States that opened in the ... 1 Introduction Dr. Ralph Coan is not well known to the general public. Originally, we had wanted to interview him as he was the medical director of the first acupuncture center in the United States that opened in the early 1970s. We wanted to know more about that center's history. Prior to visiting Dr. Coan, we found an article written by Dr. Sherman Cohn that mentioned Dr. Coan. The article noted that Dr. Coan was the founder of the American Association of Acupuncture and Oriental Medicine, which is the national association of acupuncturists and Chinese medicine practitioners in the United States. 展开更多
关键词 ACUPUNCTURE united states interview as topic history of medicine Dr. RalphCoan
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Introduction to Urban and Community Forestry in the United States of America: History, Accomplishments, Issues and Trends 被引量:3
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作者 Qi Yadong Zhang Zhiqiang 《Forestry Studies in China》 CAS 2003年第4期54-61,共8页
The urban and community forestry movement in the United States has matured over the last 20 years from managing street trees, to understanding the benefits of trees in urban ecosystems, and now to managing urban green... The urban and community forestry movement in the United States has matured over the last 20 years from managing street trees, to understanding the benefits of trees in urban ecosystems, and now to managing urban green infrastructure. This paper introduced the history, development, and major accomplishments of the urban and community forestry movement, highlighted the economic, ecological, environmental, and social values of forests and trees to communities, and discussed issues and trends of the urban and community forestry program in the United States. 展开更多
关键词 urban and community forestry urban forest benefits and values HISTORY accomplishments ISSUES trends united states
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An overview of emergency ultrasound in the United States 被引量:9
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作者 Jeremy A.Michalke 《World Journal of Emergency Medicine》 CAS 2012年第2期85-90,共6页
BACKGROUND:As emergency ultrasound use explodes around the world,it is important to realize the path its development has taken and learn from trials and tribulations of early practitioners in the field.METHODS:Approac... BACKGROUND:As emergency ultrasound use explodes around the world,it is important to realize the path its development has taken and learn from trials and tribulations of early practitioners in the field.METHODS:Approaches to education,scanning,documentation,and organization are also described.RESULTS:Machines have reduced in price and once purchased further material costs are low.Staffing costs in terms of training,etc have yet to be assessed,but indications from elsewhere are that these are low.Length of stay in the emergency department dramatically decreases,thus increasing patient satisfaction while maintaining an even higher standard of care.CONCLUSION:Emergency screening ultrasound is now a nationally accepted tool for the rapid assessment of the emergency patient. 展开更多
关键词 Emergency ultrasound united states
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History and evaluation of national-scale geochemical data sets for the United States 被引量:8
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作者 David B.Smith Steven M.Smith John D.Horton 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第2期167-183,共17页
Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geologica... Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United States.The earliest of these,here termed the 'Shacklette' data set,was generated by a U.S. Geological Survey(USGS) project conducted from 1961 to 1975.This project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous U.S.The National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance(NUREHSSR) Program of the U.S.Department of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous U.S.and Alaska.The sampled area represented about 65%of the nation.The Natural Resources Conservation Service(NRCS),from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous U.S.This data set contains analyses of more than 3000 samples.The National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the U.S.not covered by the NURE-HSSR Program.This data set contains chemical analyses for more than 70,000 samples.The USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in 2007.Sampling of three horizons or depths at more than 4800 sites in the U.S.was completed in 2010,and chemical analyses are currently ongoing.The NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the U.S.This data set currently contains data from more than 1400 sites.This paper(1) discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and(2) evaluates each data set in terms of its appropriateness as a national-scale geochemical database and its usefulness for nationalscale geochemical mapping. 展开更多
关键词 Geochemical mapping National-scale geochemical data Geochemical baselines united states
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The Future of Disability Policy and Vocational Rehabilitation in the United States 被引量:2
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作者 Henry D. Wong 《中国康复理论与实践》 CSCD 2006年第9期742-744,共3页
This article focuses on current and future disability public policy having potential implications for the Rehabilitation Act and vocational rehabilitation services in the United States. It explores several models of d... This article focuses on current and future disability public policy having potential implications for the Rehabilitation Act and vocational rehabilitation services in the United States. It explores several models of disability reflected in public policy, important historical legislation, and the relationship of the Workforce Investment Act (WIA) to the Rehabilitation Act. Competing issues and conflicts between the WIA and the state vocational rehabilitation agencies are discussed. A framework for analyzing disability policy is identified to project the future of disability policy, as well as, how these issues and conflicts may impact the survival of the rehabilitation profession. 展开更多
关键词 DISABILITY vocational rehabilitation united states
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Comparison of water resources management between China and the United States 被引量:6
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作者 Chansheng He Carol P.Harden Yanxu Liu 《Geography and Sustainability》 2020年第2期98-108,共11页
As the world’s top two economies,the United States(U.S.)and China face a number of similar water resources problems.Yet,few studies have been done to systematically compare policies and approaches on water resources ... As the world’s top two economies,the United States(U.S.)and China face a number of similar water resources problems.Yet,few studies have been done to systematically compare policies and approaches on water resources management between China and the U.S.This study compares water resources policies of China and the U.S.in the areas of national authority,water supply,water quality,and ecosystem use of the water to draw lessons learned and shed light on water resources management in China,the U.S.,and the rest of the world.The lessons learned from the comparison include six aspects.1)New paradigms of people-water harmony and a water-saving society are urgently needed to address the pressing water crisis and achieve the United Nations Sustainable Development Goals(UN SDGs).2)A comprehensive,consistent,forward-looking national policy is necessary to achieve sustainable use of water resources.3)Empowerment of river basin commissions with comprehensive authority over the integrative management of air,land,water,and biological resources in the river basin could significantly enhance the benefits and effectiveness of economic development and environmental protection.4)Expansion of water exchange through market mechanisms among water users promotes efficient and beneficial water uses.5)Use of water for ecosystem services should be an integral part of water resources management.China has set up a national blueprint for achieving ecological civilization;maintaining appropriate amounts of flow in rivers and lakes for maintenance of wildlife and fisheries and ecosystems should be institutionalized as part of this national strategy as well.6)By sharing their rich experiences and lessons in water resources management,economic development,and ecological protection with other countries,China and the U.S.can help the world to achieve global human-water harmony and the UN SDGs. 展开更多
关键词 Water resources management Comparative analysis China the united states
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Impacts of the COVID-19 pandemic on the dairy industry: Lessons from China and the United States and policy implications 被引量:3
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作者 Qingbin WANG LIU Chang-quan +4 位作者 ZHAO Yuan-feng Anthony KITSOS Mark CANNELLA WANG Shu-kun HAN Lei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第12期2903-2915,共13页
The purposes of this study are to assess the COVID-19 pandemic’s impacts on the dairy industries in China and the United States and to derive policy recommendations for enhancing the diary industries’resilience to p... The purposes of this study are to assess the COVID-19 pandemic’s impacts on the dairy industries in China and the United States and to derive policy recommendations for enhancing the diary industries’resilience to pandemics and other market shocks.Specifically,data from the two nations are used to analyze and compare the mechanisms through which the pandemic has affected their dairy industries and to discuss potential lessons from their experiences.The findings suggest that this pandemic has heavily affected the dairy industries in both China and the United States through similar mechanisms,such as decreased farmgate milk prices,disruption and difficulties of moving milk within the supply chains,worker shortages,increased production costs,and lack of operating capital.There were also significant differences in the affecting mechanisms between the two nations,including transportation difficulties from widespread road closures and significant reduction in holiday sales of dairy products in China,and the shutdown of many dairy processors in the United States due to the closing of schools,restaurants,and hotels.While government financial reliefs are highly needed to help many dairy farms and processors survive this pandemic in the short term,the dairy industries and governments need to work together to develop long-term strategies and policies to balance the industries’efficiency and flexibility,product specialization and diversification,supply chain integration and local food systems,and market mechanisms and policy regulations and interventions. 展开更多
关键词 impacts of the COVID-19 pandemic dairy industry China the united states
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Perceptions of emergency medicine residents on the quality of residency training in the United States and Saudi Arabia 被引量:1
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作者 Ahmad Aalam Mark Zocchi +6 位作者 Khalid Alyami Abdullah Shalabi Abdullah Bakhsh Asaad Alsufyani Abdulrahman Sabbagh Mohammed Alshahrani Jesse M.Pines 《World Journal of Emergency Medicine》 SCIE CAS 2018年第1期5-12,共8页
BACKGROUND: We compare educational environments(i.e. physical, emotional and intellectual experiences) of emergency medicine(EM) residents training in the United States of America(USA) and Saudi Arabia(SA).METHODS: A ... BACKGROUND: We compare educational environments(i.e. physical, emotional and intellectual experiences) of emergency medicine(EM) residents training in the United States of America(USA) and Saudi Arabia(SA).METHODS: A cross-sectional survey study was conducted using an adapted version of the validated Postgraduate Hospital Educational Environment Measure(PHEEM) survey instrument from April 2015 through June 2016 to compare educational environments in all emergency medicine residency programs in SA and three selected programs in the USA with a history of training Saudi physicians. Overall scores were compared across programs, and for subscales(autonomy, teaching, and social Support), using chi-squared, t-tests, and analysis of variance.RESULTS: A total of 219 surveys were returned for 260 residents across six programs(3 SA, 3 USA), with a response rate of 84%. Program-specific response rates varied from 79%–100%. All six residencies were qualitatively rated as "more positive than negative but room for improvement". Quantitative PHEEM scores for the USA programs were significantly higher: 118.7 compared to 109.9 for SA, P=0.001. In subscales, perceptions of social support were not different between the two countries(P=0.243); however, role autonomy(P<0.001) and teaching(P=0.005) were better in USA programs. There were no significant differences by post-graduate training year.CONCLUSION: EM residents in all three emergency medicine residency programs in SA and the three USA programs studied perceive their training as high quality in general, but with room for improvements. USA residency programs scored higher in overall quality. This was driven by more favorable perceptions of role autonomy and teaching. Understanding how residents perceive their programs may help drive targeted quality improvement efforts. 展开更多
关键词 Emergency medicine residents Residency training united states of America Saudi Arabia
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Review of the United States Refractories Industry 被引量:1
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作者 Charles E.Semler 《China's Refractories》 CAS 2003年第1期1-5,共5页
Factors affecting the U.S. refractories industry, such as decreasing demand, mergers , and decreased education are discussed, along with manufacturing statistics (i. e. , annual value and product trends ) , indicating... Factors affecting the U.S. refractories industry, such as decreasing demand, mergers , and decreased education are discussed, along with manufacturing statistics (i. e. , annual value and product trends ) , indicating that the U.S. market has declined for five straight years. Research activities have changed, with more emphasis on practical, applied projects , which have continued to produce important advances. Many challenges and opportunities remain, based on the current and future business requirements . 展开更多
关键词 Refractories situation the united states
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Soil carbon pools of six ecological regions of the United States 被引量:2
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作者 Amitava Chatterjee 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1933-1938,共6页
Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for p... Mineralisable soil organic carbon(SOC)pools vary with ecosystem type in response to changes in climate,vegetation and soil properties.Understanding the effect of climate and soil factors on SOC pools is critical for predicting change over time.Surface soil samples from six ecoregions of the United States were analyzed for permanganate oxidizable C(KMnO4-C)and mineralizable C pools.Variations of SOC ranged from 7.9 mg g^-1(Florida site)to 325 mg g^-1(Hawaii site).Mineralisable C pools and KMnO4-C were highest in soils from the Hawaii site.Mean annual precipitation explains SOC and resistant C pool variations.Clay content was related to mineralisable active C pools and bacterial abundance.Mean annual precipitation and clay content are potential variables for predicting changes in SOC pools at large spatial scales. 展开更多
关键词 Permanganate oxidizable carbon(KMnO4-C) Resistant carbon pool Mean residence time Soil carbon pools united states
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Drought and Associated Impacts in the Great Plains of the United States—A Review 被引量:1
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作者 Jeffrey B. Basara Joanna N. Maybourn +4 位作者 Casey M. Peirano Jennifer E. Tate Parker J. Brown Jake D. Hoey Brandon R. Smith 《International Journal of Geosciences》 2013年第6期72-81,共10页
The Great Plains region of the United States is susceptible to drought of all kinds including meteorological/climatological, agricultural, hydrological, and socioeconomic. Drought conditions in the region span varying... The Great Plains region of the United States is susceptible to drought of all kinds including meteorological/climatological, agricultural, hydrological, and socioeconomic. Drought conditions in the region span varying spatial and temporal scales and the causes include: 1) certain synoptic conditions that favor drought such as mid-tropospheric ridging over the drought-affected area and a weak low-level jet;2) sea surface temperature anomalies and associated teleconnections;3) land-atmosphere coupling;and 4) anthropogenic effects. While drought can span as few as a couple of months, the most severe droughts can occur at the decadal scale such as the 1930s Dust Bowl, the worst drought in recent history from a societal standpoint. Such droughts in the Great Plains have widespread impacts on agriculture, water resources, human health, and the economy. 展开更多
关键词 DROUGHT GREAT PLAINS united states RAINFALL Precipitation
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A Comparison of Shale Gas Fracturing Based on Deep and Shallow Shale Reservoirs in the United States and China 被引量:2
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作者 Qixing Zhang Bing Hou +2 位作者 Huiwen Pang Shan Liu Yue Zeng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第12期471-507,共37页
China began to build its national shale gas demonstration area in 2012.The central exploration,drilling,and development technologies for medium and shallow marine shale reservoirs with less than 3,500m of buried depth... China began to build its national shale gas demonstration area in 2012.The central exploration,drilling,and development technologies for medium and shallow marine shale reservoirs with less than 3,500m of buried depth in Changning-Weiyuan,Zhaotong,and other regions had matured.In this study,we macroscopically investigated the development history of shale gas in the United States and China and compared the physical and mechanical conditions of deep and shallow reservoirs.The comparative results revealed that themain reasons for the order-ofmagnitude difference between China’s annual shale gas output and the United States could be attributed to three aspects:reservoir buried depth,reservoir physical and mechanical properties,and engineering technology level.The current engineering technology level of China could not meet the requirements of increasing production and reducing costs for deep shale gas reservoirs;they had reached the beneficial threshold development stage and lacked the capacity for large-scale commercial production.We identified several physical and mechanical reasons for this threshold development stage.Deep shale reservoirs were affected by the bedding fracture,low brittleness index,low clay mineral content,and significant areal differences,as well as by the transformation from elasticity to plasticity,difficulty in sanding,and high mechanical and strength parameters.Simultaneously,they were accompanied by six high values of formation temperature,horizontal principal stress difference,pore pressure,fracture pressure,extension pressure,and closure pressure.The key to deep shale gas horizontal well fracturing was to improve the complexity of the hydraulic fracture network,formadequate proppant support of fracture surface,and increase the practical stimulated reservoir volume(SRV),which accompanied visual hydraulic discrete network monitoring.On this basis,we proposed several ideas to improve China’s deep shale gas development involving advanced technology systems,developing tools,and supporting technologies in shale gas exploration and development in the United States.These ideas primarily involved stimulation technologies,such as vertically integrated dessert identification and optimization,horizontal well multistage/multicluster fracturing,staged tools development for horizontal wells,fractures network morphology monitoring by microseismic and distributed optical fiber,shale hydration expansion,soak well,and fracturing fluid flow back.China initially developed the critical technology of horizontal well large-scale and high-strength volume fracturing with a core of“staged fracturing with dense cutting+shorter cluster spacing+fracture reorientation by pitching+forced-sand addition+increasing diameter perforating+proppant combination by high strength and small particle size particles”.We concluded that China should continue to conduct critical research on theories and technical methods of horizontal well fracturing,suitable for domestic deep and ultra-deep marine and marine-continental sedimentary shale,to support and promote the efficient development of shale gas in China in the future.It is essential to balance the relationship between the overall utilization degree of the gas reservoir and associated economic benefits and to localize some essential tools and supporting technologies.These findings can contribute to the flourishing developments of China’s deep shale gas. 展开更多
关键词 Deep and shallow shale in the united states and China physical and mechanical properties multistage/multicluster fractures network monitoring soak well and flow back
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Challenges of agriculture and food systems issues in China and the United States 被引量:1
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作者 Gregory Veeck Ann Veeck Hongyan Yu 《Geography and Sustainability》 2020年第2期109-117,共9页
China and the United States are the two most significant nations in the contemporary global food and agricultural network.In addition,they are two of the most important innovators with respect to the development of ne... China and the United States are the two most significant nations in the contemporary global food and agricultural network.In addition,they are two of the most important innovators with respect to the development of new crop varieties,agro-technologies,farm products,markets and consumer issues,such as consumer resistance to genetically modified foods,among others.In the face of an ever-complex web of interactions,technologies and products among producers and consumers in both nations,there are far more structural similarities than differences in the food and agriculture sectors of these two nations.This essay,adopting some of the themes of the Sino-American Symposium on Future Issues Affecting Quality of Life,presents a limited but representative comparative assessment of three of the most important shared challenges impacting the agricultural sectors of China and the United States for the period from 2000 to the present including 1)environmental challenges related to agricultural water supply,2)declines in farm labor and rural population,and 3)growing food-related concerns and challenges.For both nations,excessive and unsustainable groundwater consumption has lowered water tables and limited crop production.Rural populations and farm workforces in both nations are also declining,leading to labor challenges in both nations.Finally,concerns regarding food safety are also very similar with major challenges to the farm sector associated with consumer resistance to genetically modified food crops and sanitation issues linked to lengthening supply chains.All of these issues threaten the development of sustainable agricultural production systems. 展开更多
关键词 AGRICULTURE Food safety China united states Sino-US comparative study
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The Changing Face of High Performance Computing in the United States 被引量:2
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作者 Ann Haves(Advanced Computing Laboratory Los Alamos National Laboratory Los Alamos. NM 87545, USA) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期309-311,共3页
TheChangingFaceofHighPerformanceComputingintheUnitedStatesAnnHaves(AdvancedComputingLaboratoryLosAlamosNatio... TheChangingFaceofHighPerformanceComputingintheUnitedStatesAnnHaves(AdvancedComputingLaboratoryLosAlamosNationalLaboratoryLosA... 展开更多
关键词 the Changing Face of High Performance Computing in the united states
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