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HIV care services and the executive orders of the United States on USAID:Insights from the Philippines
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作者 Rowalt Alibudbud 《Asian Pacific Journal of Tropical Medicine》 2025年第4期147-148,共2页
In January 2025,the United States issued executive orders that could potentially curtail lesbian,gay,bisexual,transgender,queer,and other sexual and gender minorities(LGBTQ+)rights and federal aid to developing countr... In January 2025,the United States issued executive orders that could potentially curtail lesbian,gay,bisexual,transgender,queer,and other sexual and gender minorities(LGBTQ+)rights and federal aid to developing countries,such as public health programs under the United States Agency for International Development(USAID)[1,2].In the Philippines,USAID has played an important role in funding and supporting initiatives to address the country’s local HIV epidemic[2,3]. 展开更多
关键词 executive orders USAID HIV care services hiv epidemic public health programs funding supporting initiatives united states
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The Strategic Game Between the United States and Russia and the New Developments in the Regional Situation in Central Asia
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作者 Gu Wei 《Contemporary World》 2025年第5期22-28,共7页
Located at the intersection of the east,west,south and north,Central Asia has attracted the attention of major international actors due to its unique geographical location.On one hand,major powers and actors outside t... Located at the intersection of the east,west,south and north,Central Asia has attracted the attention of major international actors due to its unique geographical location.On one hand,major powers and actors outside the region such as the European Union(EU)and the Gulf Cooperation Council have strengthened their ties with Central Asian countries,significantly intensifying the power struggles and institutional competition in the region.On the other hand,Central Asian countries have become increasingly active,developing their foreign relations while seeking strategic autonomy and promoting regional cooperation. 展开更多
关键词 RUSSIA gulf cooperation council European Union power struggles strategic game central asian major international actors united states
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Demographic trends in mortality due to ovarian cancer in the United States,1999-2020
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作者 Laiba Razaq Arkadeep Dhali +8 位作者 Rick Maity Abdul Rafae Faisal Ali Shan Hafeez Asad Zaman Mohammad Abdullah Humayun Muhammad Faizan Mavra Shahid Mamoona Majeed Pramod Singh 《World Journal of Clinical Oncology》 2025年第6期189-206,共18页
BACKGROUND Ovarian carcinoma has the highest mortality rate among all gynecological cancers.Several reproductive and hormonal risk factors,including early menarche,late menopause,limited use of oral contraceptives,and... BACKGROUND Ovarian carcinoma has the highest mortality rate among all gynecological cancers.Several reproductive and hormonal risk factors,including early menarche,late menopause,limited use of oral contraceptives,and a low pregnancy rate,have been identified as contributors to the increased susceptibility to ovarian cancer.Advancements in cancer therapy over the past century,including the emergence of precision oncology,underscore the importance of early detection and tailored interventions,factors particularly critical in ovarian cancer,where late-stage diagnosis remains a persistent barrier to survival.This challenge is compounded by the lack of a universally endorsed screening program,resulting in late-stage identification and widespread metastasis.AIM To evaluate demographic differences in ovarian cancer-related mortality from 1999 to 2020 among adult females aged≥25 years within the United States.METHODS Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research database was used to collect de-identified death certificate data for malignant neoplasm of the ovaries related deaths in female adults aged 25 years and older from the year 1999 to 2020.Crude mortality rates and age-adjusted mortality rates(AAMRs)per 100000 people were calculated.Join point regression program was used to assess annual percent changes in mortality trends,with statistical significance set at P value<0.05.RESULTS Between 1999 and 2020,337619 deaths due to ovarian cancer occurred among United States females aged 25 to>85.The AAMR decreased from 14.62 in 1999 to 10.15 in 2020,with significant declines across various demographics.The AAMRs were highest among non-Hispanic White women,i.e.,13.53.Based on region,they were the highest in the Northeast(13.06)and Midwest(12.94).The steepest decline was observed in metropolitan areas as compared to nonmetropolitan ones.The study highlights significant progress in reducing ovarian cancer mortality across age,race/ethnicity,and geographic regions during this period.CONCLUSION The mortality trends for ovarian carcinoma patients showed an overall decrease,with the highest mortality rates observed among older individuals(65 to>85 years)and non-Hispanic Whites.These disparities underscore the need for equitable healthcare access and targeted policy interventions. 展开更多
关键词 Ovarian cancer Ovarian carcinoma MORTALITY Crude mortality rate Age-adjusted mortality rate Demographic trends united states
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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:7
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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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Geologic characteristics,exploration and production progress of shale oil and gas in the United States:An overview 被引量:8
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作者 MCMAHON T P LARSON T E +1 位作者 ZHANG T SHUSTER M 《Petroleum Exploration and Development》 SCIE 2024年第4期925-948,共24页
We present a systematic summary of the geological characteristics,exploration and development history and current state of shale oil and gas in the United States.The hydrocarbon-rich shales in the major shale basins o... We present a systematic summary of the geological characteristics,exploration and development history and current state of shale oil and gas in the United States.The hydrocarbon-rich shales in the major shale basins of the United States are mainly developed in six geological periods:Middle Ordovician,Middle-Late Devonian,Early Carboniferous(Middle-Late Mississippi),Early Permian,Late Jurassic,and Late Cretaceous(Cenomanian-Turonian).Depositional environments for these shales include intra-cratonic basins,foreland basins,and passive continental margins.Paleozoic hydrocarbon-rich shales are mainly developed in six basins,including the Appalachian Basin(Utica and Marcellus shales),Anadarko Basin(Woodford Shale),Williston Basin(Bakken Shale),Arkoma Basin(Fayetteville Shale),Fort Worth Basin(Barnett Shale),and the Wolfcamp and Leonardian Spraberry/Bone Springs shale plays of the Permian Basin.The Mesozoic hydrocarbon-rich shales are mainly developed on the margins of the Gulf of Mexico Basin(Haynesville and Eagle Ford)or in various Rocky Mountain basins(Niobrara Formation,mainly in the Denver and Powder River basins).The detailed analysis of shale plays reveals that the shales are different in facies and mineral components,and"shale reservoirs"are often not shale at all.The United States is abundant in shale oil and gas,with the in-place resources exceeding 0.246×10^(12)t and 290×10^(12)m^(3),respectively.Before the emergence of horizontal well hydraulic fracturing technology to kick off the"shale revolution",the United States had experienced two decades of exploration and production practices,as well as theory and technology development.In 2007-2023,shale oil and gas production in the United States increased from approximately 11.2×10^(4)tons of oil equivalent per day(toe/d)to over 300.0×10^(4)toe/d.In 2017,the shale oil and gas production exceeded the conventional oil and gas production in the country.In 2023,the contribution from shale plays to the total U.S.oil and gas production remained above 60%.The development of shale oil and gas has largely been driven by improvements in drilling and completion technologies,with much of the recent effort focused on“cube development”or“co-development”.Other efforts to improve productivity and efficiency include refracturing,enhanced oil recovery,and drilling of“U-shaped”wells.Given the significant resources base and continued technological improvements,shale oil and gas production will continue to contribute significant volumes to total U.S.hydrocarbon production. 展开更多
关键词 united states shale oil shale gas shale reservoirs unconventional reservoirs oil and gas production resource assessment
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Factors associated with nursing students' willingness to care for older adults in Korea and the United States 被引量:6
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作者 Insun Jang Doonam Oh Yeon Sook Kim 《International Journal of Nursing Sciences》 CSCD 2019年第4期426-431,共6页
Objective: Elderly health care needs increase and nurses' role for elderlies is vital.It is significant to identify nursing students' intention to care for elderlies.Thus,this study investigated nursing studen... Objective: Elderly health care needs increase and nurses' role for elderlies is vital.It is significant to identify nursing students' intention to care for elderlies.Thus,this study investigated nursing students' willingness to care for elderlies in Korea and the United States.Methods: The study was conducted with 437 undergraduate nursing students from Korea and the United States from May 25 to 31,2018.Participants completed a survey including frequency and quality of contact,anxiety about aging,empathy,attitude toward elderly,and willingness to care.Results: Study findings from the entire group showed that nursing students' willingness to care for the elderly was positively associated with contact quality (β =0.22,P<0.001) and empathy (β =0.12,P 0.009) but negatively associated with anxiety about aging (β =0.23,P < 0.001) and attitude toward the elderly (β =0.14,P =0.004).Contact quality (β=0.30,P < 0.001) was positively associated with the willingness to care in Korean students,whereas extended family living type (β =-0.15,P=0.012) and attitude toward the elderly (β =-0.18,P=0.005) negatively associated in US students.Conclusion: This study suggested that nursing educators reinforce contact quality and empathy but reduce anxiety about aging and attitude toward elderly to enhance future nurses' care quality. 展开更多
关键词 ATTITUDE Baccalaureate nursing education ELDERLY EMPATHY Nursing care Republic of Korea united states
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Dr.William Prensky:The birth of the acupuncture profession in the United States(1969–1979)——the Institute for Taoist Studies and the National Acupuncture Association 被引量:5
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作者 Arthur Yin Fan 《Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第1期5-11,共7页
Acupuncture is one important part of traditional Chinese medicine (here after, the author will only use the term "acupuncture" to denote both acupuncture and Chinese medicine) and is a fast growing profession in r... Acupuncture is one important part of traditional Chinese medicine (here after, the author will only use the term "acupuncture" to denote both acupuncture and Chinese medicine) and is a fast growing profession in recent years. Many patients have benefited from acupuncture therapy because acupuncture is a safe, effective and natural therapy. Several articles and interviews published in recent years have described the history of the establishment of acupuncture and Chinese medicine on the east and west coasts of the United States (U.S.) of America. 展开更多
关键词 ACUPUNCTURE united states history of medicine Gim Shek Ju Tin Yau So William Prensky School
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Comparison of RN licensure examination: China and the United States 被引量:6
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作者 Jianlin Hou Shengyu Chen +3 位作者 Sabhyta Sabharwal Victoria Fan Minghui Yan Weimin Wang 《International Journal of Nursing Sciences》 CSCD 2019年第1期111-116,共6页
Having the two largest nursing workforces across the globe,both China and the United States have implemented licensure examinations to standardize the qualifications of registered nurse.China established the National ... Having the two largest nursing workforces across the globe,both China and the United States have implemented licensure examinations to standardize the qualifications of registered nurse.China established the National Nursing Licensure Examination(NNLE)in 1995.Like the National Council Licensure Examination for Registered Nurses(NCLEX-RN)in the United States,the NNLE has become an important link in the nurse registration process and contributed a lot in quality assurance and development of nursing profession.It may be necessary for the NNLE to learn from NCLEX-RN in several aspects,including increasing the frequency of exam,providing examinees with individualized services,and continuing reforming exam content and format.By better aligning the content and format of the examination with the current nursing paradigm and clinical requirements,nurses may enter the healthcare field better prepared to care for patients.Considering the magnitude of their nursing workforce,both China and the United States have great potential to serve as a role model for other developing countries as they look towards establishing national nursing education programs.As new policies around standardized nurse education in China take form,we urge that the NNLE be included alongside curricular reforms.As these reforms are implemented,continued research will be needed to evaluate the effectiveness of curriculum and licensure exam regulations upon nurse preparedness and quality of nursing care in China. 展开更多
关键词 China EXAMINATION LICENSURE Nursing education The united states
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Dr. Gene Bruno: The beginning of the acupuncture profession in the United States(1969–1979) — acupuncture, medical acupuncture and animal acupuncture 被引量:5
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作者 Arthur Yin Fan Sarah Faggert 《Journal of Integrative Medicine》 SCIE CAS CSCD 2015年第5期281-288,共8页
Acupuncture was practiced by both Western medical doctorst and Chinese medicine doctorst in the United States (U.S.) in the 19th century; however, after 1910, it seems that people seldom heard about it until it was ... Acupuncture was practiced by both Western medical doctorst and Chinese medicine doctorst in the United States (U.S.) in the 19th century; however, after 1910, it seems that people seldom heard about it until it was re-introduced during the 1960s-1970s. Acupuncture legislation, acupuncture practice and the start of acupuncture education were some of the events that marked the re-introduction of acupuncture in the U.S.. 展开更多
关键词 ACUPUNCTURE united states history Of medicine Gim Shek Ju Tin Yau So Gene Bruno Animal Acupuncture
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Comparison of water resources management between China and the United States 被引量:11
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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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Depression in the context of chronic diseases in the United States and China 被引量:4
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作者 Hongjin Li Song Ge +1 位作者 Brian Greene Jacqueline Dunbar-Jacob 《International Journal of Nursing Sciences》 CSCD 2019年第1期117-122,共6页
Depression is not only a major global public health concern,but also a common comorbidity among patients who experience chronic diseases,such as cancer,stroke,heart disease,diabetes,and chronic obstructive pulmonary d... Depression is not only a major global public health concern,but also a common comorbidity among patients who experience chronic diseases,such as cancer,stroke,heart disease,diabetes,and chronic obstructive pulmonary disease.Yet the recognition and treatment varies widely around the world.This study(1)provides an integrated review of the literature on the prevalence of depression among patients with chronic diseases in China and the United States and its relationship to poorer health outcomes and(2)compares the differences in the percentages of patients receiving treatments for depression between the United States and China.Given the current situation,we recommended that primary care and specialty providers should be knowledgeable and alert regarding the signs of depression.Efforts should be directed to further implement integrated care based interventions to manage depression and improve quality of life among patients suffering chronic diseases in both China and the United States. 展开更多
关键词 Chronic disease China DEPRESSION united states
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The legendary life of Dr.Gim Shek Ju, the founding father of the education of acupuncture and Chinese medicine in the United States 被引量:3
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作者 Arthur Yin Fan 《Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第3期159-164,共6页
Several stories of various pioneers establishing acupuncture and Chinese medicine (ACM) practices in the United States (U.S.) have been documented. However, the establishment of schools for ACM signaled the establ... Several stories of various pioneers establishing acupuncture and Chinese medicine (ACM) practices in the United States (U.S.) have been documented. However, the establishment of schools for ACM signaled the establishment of ACM as an established profession in the U.S. One of the first persons who wanted to set-up a school for Chinese medicine in the U.S. was Dr. Tom Foo Yuen (谭富园, August 7, 1858 - July 10, 1947) during the late 1800s in Los Angeles (LA), California. However, it was not until 1969 or 1970 that the first informal ACM school was actually established in the U.S. This school was called the Institute for Taoist Study, and was located in LA. However, this school was not registered with the local government and Dr. Gim Shek Ju was the sole teacher at that time. 展开更多
关键词 ACUPUNCTURE Chinese medicine united states EDUCATION history of medicine Gim Shek Ju
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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:4
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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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Undergraduate nursing education in the United States 被引量:6
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作者 Susan A. LaRocco 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第1期44-49,共6页
Nursing education in the United States began in the 1870s with hospital training schools modeled after the Nightingale plan. Presently there are three educational paths that students may take to become a registered nu... Nursing education in the United States began in the 1870s with hospital training schools modeled after the Nightingale plan. Presently there are three educational paths that students may take to become a registered nurse (RN). These are the baccalaureate degree (BS), the associate degree (AD) and the diploma. Accelerated nursing programs are also available for people who have a baccalaureate degree in another field. Nursing education and nursing practice in the United States is regulated by each of the 50 states. The focus of nursing education is the preparation of nurses who use critical thinking skills to provide comprehensive patient-centered care to a variety of clients. It is expected that nurses will function using evidence-based practice in a culturally competent, safe manner. Nursing schools must be approved by the state in which they exist. In addition to this, most nursing schools are also accredited, a voluntary process that is done by a non-governmental association. All graduates take the same licensing exam, a computer adaptive test that is from 75 to 265 items long educated graduates were first time test takers; 85.5% passed the exam. Trends in nursing education In 2008 almost 120,000 US include a focus on evidence based practice, an emphasis on safety and quality, patient education and management of chronic conditions, genetics and genomics and the use of simulation in nursing education 展开更多
关键词 Nursing education Nurse licensure united states of America
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Soil carbon pools of six ecological regions of the United States 被引量:3
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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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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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A Comparison of Shale Gas Fracturing Based on Deep and Shallow Shale Reservoirs in the United States and China 被引量:3
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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:4
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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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