Plant height has been a major target for selection of high-yielding varieties in wheat.Two height-reducing loci(Rht-B1 and Rht-D1)have been widely used since the Green Revolution.However,these genes also negatively af...Plant height has been a major target for selection of high-yielding varieties in wheat.Two height-reducing loci(Rht-B1 and Rht-D1)have been widely used since the Green Revolution.However,these genes also negatively affect other agronomic traits such as kernel weight.Identifying alternative height-reducing loci could benefit wheat improvement.This study focused on the genetics of plant height in 260 historical and contemporary winter wheat accessions via genome-wide association studies using 38,693 single nucleotide polymorphism(SNP)markers generated through genotyping by sequencing,two Kompetitive Allele Specific Polymorphismmarkers,and phenotypic data recorded in two seasons(2016 and 2018).The 260 accessions showed wide variation in plant height.Most accessions developed after 1960 were shorter than earlier accessions.The broad-sense heritability for plant height was high(H2=0.82),whichwas also supported by a high correlation(r=0.82,P<0.0001)between heights from the two years.We detected a total of 16 marker–trait associations(MTAs)for plant height at–lg(P)≥4.0 on chromosomes 1A,2B,2D,3B,4D,5A,5D,6A,6B,7A,and 7D.We detected three of the MTAs(QPLH-2D,QPLH-4B.2,and QPLH-4D)consistently in individual-year and combined-year analyses.These MTAs individually explained 10%–16%of phenotypic variation.The heightreducing alleles at these threeMTAs appeared after 1960 and increased in frequency thereafter.Among the genes near these loci were gibberellic acid insensitive(GAI)and GRAS transcription factor(GIBBERELLIC-ACID INSENSITIVE(GAI),REPRESSOR of GAI(RGA),and SCARECROW(SCR)).The evidence from this study and previous reports suggests that QPLH-2D is Rht8.A gene encoding a GRAS transcription factor is located near QPLH-2D.Validation of the QPLH-2D locus and associated candidate genes awaits further study.展开更多
A review of the period of unregulated exploitation of forests in the state of West Virginia (U.S.) and in Shaanxi Province, PRC was presented. Economic and ecological recovery from exploitation has been different in t...A review of the period of unregulated exploitation of forests in the state of West Virginia (U.S.) and in Shaanxi Province, PRC was presented. Economic and ecological recovery from exploitation has been different in the two regions due to basic differences in nature of the forest and in the degree and persistence of exploitive pressures. After a century since unregulated exploitation, West Virginia forests are well on the road to management for sustainability and conservation. Shaanxi's recovery from overuse and unregulated exploitation is less certain; forests are still in the early phases of ecological recovery there. Full recovery to a period of sustainability will take a century or longer. Suggestions are made for measures needed to enhance the forest recovery. Keywords Forests - Shaanxi - West Virginia - Central China - Forest exploitation - Recovery CLC number S754 Document code A Article ID 1007-662X(2004)01-0049-06 Foundation item: The project was sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (2002–2004) and Shaanxi Provincial Foreign Expert Bureau (2003).Biography: Jack E. Coster (1935-), male, professor of West Virginia University, Morgantown, West Virginia. U.S.A.Responsible editor: Song Funan展开更多
The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that incl...The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Louisiana-Mississippi, U.S.A.) upstream to rkm 1504(Missouri-Kentucky, U.S.A.). Four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).Fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. Fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. Conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. Future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent secondary channels in selected river reaches. However, temporary secondary channels also contain unique fish species, and also appear to be important sites of riverine primary production. Restoration strategies should consider a balance of both secondary channel types, which should support the greatest biodiversity for the LMR ecosystem.展开更多
In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-f...In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-first century projections indicate accelerating climate change and cascading ecological consequences.Effects observed to date include large-scale forest dieback,large and severe wildfires,and changes in the flow regimes of rivers and streams with attendant changes to riparian and aquatic ecosystems.Rising temperatures and changing precipitation patterns are pushing ecosystems across physiological and ecological thresholds,causing widespread mortality and,in some cases,major changes in composition,structure and function.These changes have prompted action by the conservation community to reduce the adverse effects of climate change.The Southwest Climate Change Initiative(SWCCI),a project led by The Nature Conservancy,works with local stakeholders in affected landscapes,reduces adverse impacts on ecological and social systems using scientific knowledge and practical tools.The Initiative has learned through practical experience that: 1) managers must embrace change and manage for resilience rather than resistance;2) strong local science-management partnerships are critical to effective adaptation planning and implementation;3) planners and managers must broaden the scope and accelerate the pace of conservation activities if ecosystem services are to be sustained;4) adaptation often does not require radically new or different management practices,rather,conservationists already have many of the tools they need;and 5) rapid documentation and widespread communication of methods and findings can build rapidly regional capacity for climate change adaptation.Our experience suggests that adaptation efforts can be effective if they are focused at the local scale;employ learning networks;and engage in ecosystem-based adaptation:the sustainable management,conservation and restoration of ecosystems so that they continue to provide the services that allow people to thrive in changing environments.展开更多
Use of hyperspectral spectroradiometers allows for information on different light bands to be captured, allowing for identification of plant health status. Apple scab is the most important disease in the production of...Use of hyperspectral spectroradiometers allows for information on different light bands to be captured, allowing for identification of plant health status. Apple scab is the most important disease in the production of apples. RIMpro is a web-based decision support system (DDS) for orchardists that has the capacity to improve optimal fungicide application for the control of apple scab and has the potential to reduce the number of applications and thereby reduce input expenses. The objective of this study was to complete a hyperspectral assessment of apple leaves in order to evaluate the spectral characteristics of trees sprayed according to forecasted infection events from the DDS. No significant differences in visual assessments or vegetation indices were observed between conventionally treated leaves and leaves treated according to the DSS. In the first year of this study two fungicide treatments were eliminated, in the second one fungicide treatment was eliminated. This finding is important because it provides evidence that plant health status is similar between conventionally sprayed trees and trees on a DSS-guided reduced spray program. In addition, the use of spectroradiometers for assessing the efficacy of different fungicide programs was demonstrated. Finally, potassium bicarbonate tank-mixed with sulfur was confirmed to be an effective spray material for managing apple scab. By integrating the precise information provided by DSSs and the use of biorational pesticides, agricultural producers, service providers and educators are able to adapt climate change considerations and action-oriented decisions into pest management plans.展开更多
The fundamental reason for Sino-U.S.'trust deficit' is the narrowing of the gap between the two countries' national strengths and the subsequent change in U.S.policy.Especially the U.S.involvement in marit...The fundamental reason for Sino-U.S.'trust deficit' is the narrowing of the gap between the two countries' national strengths and the subsequent change in U.S.policy.Especially the U.S.involvement in maritime disputes between China and her neighbors have further complicated bilateral relations.The two countries should make concerted efforts to improve cooperation and trust and seek to build a new type of great power relationship.展开更多
This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland ca...This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland category comprised 17.7% of timber land area on all private and public lands in the South. This included 4.25 million ha of hydric sites;0.77 million ha mesic wet;9.55 million ha mesic, with only seasonal access;for a total of 14.57 million ha. The Natural Resource Inventory (NRI) for 2012 on private lands estimated that there were 14.71 million ha forested wetlands, which comprised 17.7% of all forested private forest area. The 2015 National Land Cover Data for the South estimated that there were 17.8 million ha of woody wetlands, which comprised 8% to 12% of the southern land area, and there were also 4.45 million ha of emergent herbaceous sites. About 10% of the southern timber forest sector would be based on harvests from wetland forests economy ($455 million per year), while the 17.7% of wetland land area would provide a proportional share of the annual nontimber forest products ($44 million) and payments for ecosystem services ($134 million). Wetlands also provide important nontimber forest products, and ecosystem services, which are beginning to develop active private and public markets.展开更多
CHINESE President Xi Jinping and his U.S.counterpart Barack Obama resumed their round of meetings with their latest meeting at the end of September 2015.This was their third summit following their meetings at Sunnylan...CHINESE President Xi Jinping and his U.S.counterpart Barack Obama resumed their round of meetings with their latest meeting at the end of September 2015.This was their third summit following their meetings at Sunnylands,California and evening talks at Yingtai,Beijing.If the week President Nixon spent in China was"a week that changed the world,"then the week during which President Xi paid a state visit to the U.S.and attended UN conferences may be called"a week that will shape the future."展开更多
The U.S.bombing of Caracas,Venezuela,and kidnapping of its democratically elected president Nicolas Maduro in the early hours of January 3,of course,violated an international law regime that the U.S.Government has nev...The U.S.bombing of Caracas,Venezuela,and kidnapping of its democratically elected president Nicolas Maduro in the early hours of January 3,of course,violated an international law regime that the U.S.Government has never had much respect for.Nonetheless,the openness of the discourse surrounding the U.S.'imperial bellicosity is novel in the modem era.展开更多
Geopolitically,many in China longconsidered Latin America a distantregion-almost"the end of the Earth."That perception has changed dramatically.Over the past two decades,a steadilywarming relationship,driven...Geopolitically,many in China longconsidered Latin America a distantregion-almost"the end of the Earth."That perception has changed dramatically.Over the past two decades,a steadilywarming relationship,driven largely by expanding commercial ties,has taken shape.展开更多
As two of the largest economies and countries in theworld,the People’sRepublic of China(China)and the United States of America(U.S.)both have enormous resources and innovative talents in a number of sectors.Cooperati...As two of the largest economies and countries in theworld,the People’sRepublic of China(China)and the United States of America(U.S.)both have enormous resources and innovative talents in a number of sectors.Cooperation between both sides will be hugely beneficial to the world population,and this is especially the case with healthcare.The U.S.-China Track II Dialogue on Healthcare was set up as a forum to discuss and engage ideas on this very topic.In this dialogue,Dr.Qun Yan,head of the hLife Editorial Office engages in a dialogue with Professor Mark McClellan,the Director of the Duke-Margolis Institute for Health Policy at Duke University and U.S.Co-Chair of the Track Ⅱ Dialogue on Healthcare,Professor Gordon G Liu,Professor at Peking University and the Dean of the PKU Institute for Global Health andDevelopment andCo-Organizer of the Track Ⅱ Dialogue,Mr.Stephen Orlins,President of the National Committee on U.S.-China Relations and a Co-Organizer of the Track Ⅱ Dialogue,and Professor George Fu Gao,Academician at the Chinese Academy of Sciences and formerDirector of the Chinese Center for Disease Control and Prevention.They discuss how and why the Track Ⅱ Dialogue was created,the successes and developments of the dialogues,and what the future of American-Chinese health collaboration looks like.展开更多
Whenever U.S.Presibent Donald Trump talks about the U.S.fentanyl crisis,he will especially blame China for causing it That rhetoric does not hold up to scrutiny.At the beginning of this century,almost 800 Americans di...Whenever U.S.Presibent Donald Trump talks about the U.S.fentanyl crisis,he will especially blame China for causing it That rhetoric does not hold up to scrutiny.At the beginning of this century,almost 800 Americans died from a fentanyl overdose.Fast forward to 2021.and more than 107,000 deaths were traced to the drug in that year alone.How is it possible that in roughly 20 years,the number of deaths had spiked over 13,000 percent?The answer is a complex one:Politicians are not interested in delivering such answers.Instead,they live in a world in which deflection and blaume generate headlines.And we know anytime a politician blames China that news covernage is soon to follow.展开更多
I offer suggestions to increase the probability of success of an international research project.Collaborative studies often produce more innovative and transformative scientific results than work done by a single inve...I offer suggestions to increase the probability of success of an international research project.Collaborative studies often produce more innovative and transformative scientific results than work done by a single investigator or an isolated team.My advice is intended for early-career scientists.The product of the collaboration may be high-impact research publications,enhanced geophysical monitoring capabilities in a foreign country,or an advanced training course.Choosing the right international partner is the most important step.Keeping an open mind and being receptive to suggestions to modify the initial concept is critical.Other key steps include having a mutually agreed upon plan with achievable goals and well-defined expected outcomes.International cooperation is a richly rewarding experience that accelerates progress in the Earth Sciences.展开更多
The Leafminers,representing a diverse group of insects from various genera within the Agromyzidae family,pose a significant threat to spinach(Spinacia oleracea L.)production.This study aimed to identify single nucleot...The Leafminers,representing a diverse group of insects from various genera within the Agromyzidae family,pose a significant threat to spinach(Spinacia oleracea L.)production.This study aimed to identify single nucleotide polymorphism(SNP)markers associated with leafminer resistance through a genome-wide association study(GWAS)and to evaluate the prediction accuracy(PA)for selecting resistant spinach using genomic prediction(GP).Using a dataset of 84301 SNPs obtained from whole-genome resequencing,seven GWAS models,including BLINK,FarmCPU,MLM,and MLMM in GAPIT 3,as well as MLM,GLM,and SMR in TASSEL 5,were employed to perform GWAS on a panel of 286 USDA spinach germplasm accessions.Three SNP markers,namely 1_115279256_C_T,3_157082529_C_T,and 4_168510908_T_G on chromosomes 1,3,and 4,respectively,were identified as associated with leafminer resistance.In the 30 kb flanking regions of these markers,four candidate genes(SOV1g031330,SOV1g031340,SOV4g047270,and SOV4g047280),encoding LOB domain-containing protein,KH domain-containing protein,were discovered.Nodulin-like domain-containing protein,and SAM domain-containing protein,were discovered.The PA for leafminer resistance selection was estimated using ten different SNP sets,including two GWAS-derived marker sets(three and 51 SNPs)and eight random marker sets(ranging from 51 to 10 K SNPs)analyzed by seven GP models.The findings emphasized the superior performance of GWAS-derived SNP sets,reaching a PA of up to 0.79 using the cBLUP model.Notably,this research marks the pioneering application of GP in the context of insect resistance,providing a significant advancement in the understanding and management of leafminer resistance in spinach cultivation.展开更多
Acute exposure to high altitude can cause acute altitude illnesses and is associated with impaired cognitive and physical performance.The most effective preventive strategies currently recommended include environmenta...Acute exposure to high altitude can cause acute altitude illnesses and is associated with impaired cognitive and physical performance.The most effective preventive strategies currently recommended include environmental acclimatization(slow ascent and/or pre-acclimatization)or pharmacological support of acclimatization using acetazolamide.However,these strategies are not practical for high-altitude exposures that require rapid and unplanned ascent,high physical and mental performance,such as rescue missions or military operations.Dexamethasone and other modulators of the glucocorticoid system take effect quickly and are effective alternatives for preventing acute altitude illnesses when rapidly ascending to high altitudes.As the efficacy of dexamethasone in preventing acute mountain illnesses remains controversial,a review of existing studies on the use of dexamethasone for the prevention of acute mountain sickness was conducted,aiming to determine the best strategy.Possible mechanisms of protection against acute altitude illnesses are discussed based on the results of clinical trials.The data indicate that dexamethasone is most effective at altitudes above 4000 m at doses of 8–16 mg/d.Appropriately designed and powered trials are needed to obtain more evidence-based results on the dosage and timing of dexamethasone administration,and to provide optimized recommendations for the application of this powerful pharmacological tool.展开更多
For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain...For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain a shrinking but significant component of U.S. electricity production. Natural gas-fired technologies are dispatchable and versatile generation sources, but the recent and anticipated growth of wind and solar technologies will add nondispatchable, intermittent power generation sources to U.S.electricity grids. Numerous emissions-related benefits arise from the deployment of these technologies, but they must coexist with coal plants, many of which run most efficiently under baseload operating procedures. Historical monthly emissions data has been analyzed on a sample of coal plants to show how modified coal operations have affected plant emission rates, as measured by carbon dioxide emitted per unit of electricity output. Statistically significant correlations between plant capacity factors and emission rate intensity have been observed by the majority of the sample, showing a worsening under more sporadic operations. Since nearly all of the coal plants in the sample are generating less electricity, determining the emission impact of operational decisions will assist policymakers as they seek to minimize total system emissions without severe disruptions to electricity cost and service reliability.展开更多
基金The authors thank the National Small Grains Collection,USDA for providing seed of historical wheat accessions.Financial support from USDA Hatch Grant 1013073 to MM via Purdue College of Agriculture is greatly appreciated.
文摘Plant height has been a major target for selection of high-yielding varieties in wheat.Two height-reducing loci(Rht-B1 and Rht-D1)have been widely used since the Green Revolution.However,these genes also negatively affect other agronomic traits such as kernel weight.Identifying alternative height-reducing loci could benefit wheat improvement.This study focused on the genetics of plant height in 260 historical and contemporary winter wheat accessions via genome-wide association studies using 38,693 single nucleotide polymorphism(SNP)markers generated through genotyping by sequencing,two Kompetitive Allele Specific Polymorphismmarkers,and phenotypic data recorded in two seasons(2016 and 2018).The 260 accessions showed wide variation in plant height.Most accessions developed after 1960 were shorter than earlier accessions.The broad-sense heritability for plant height was high(H2=0.82),whichwas also supported by a high correlation(r=0.82,P<0.0001)between heights from the two years.We detected a total of 16 marker–trait associations(MTAs)for plant height at–lg(P)≥4.0 on chromosomes 1A,2B,2D,3B,4D,5A,5D,6A,6B,7A,and 7D.We detected three of the MTAs(QPLH-2D,QPLH-4B.2,and QPLH-4D)consistently in individual-year and combined-year analyses.These MTAs individually explained 10%–16%of phenotypic variation.The heightreducing alleles at these threeMTAs appeared after 1960 and increased in frequency thereafter.Among the genes near these loci were gibberellic acid insensitive(GAI)and GRAS transcription factor(GIBBERELLIC-ACID INSENSITIVE(GAI),REPRESSOR of GAI(RGA),and SCARECROW(SCR)).The evidence from this study and previous reports suggests that QPLH-2D is Rht8.A gene encoding a GRAS transcription factor is located near QPLH-2D.Validation of the QPLH-2D locus and associated candidate genes awaits further study.
基金The Scientific Research Foundation for the Returned Overseas Chinese Scholars State Education Ministry(2002-2004)and Shaanxi Provincial Foreign Expert Bureau (2003).
文摘A review of the period of unregulated exploitation of forests in the state of West Virginia (U.S.) and in Shaanxi Province, PRC was presented. Economic and ecological recovery from exploitation has been different in the two regions due to basic differences in nature of the forest and in the degree and persistence of exploitive pressures. After a century since unregulated exploitation, West Virginia forests are well on the road to management for sustainability and conservation. Shaanxi's recovery from overuse and unregulated exploitation is less certain; forests are still in the early phases of ecological recovery there. Full recovery to a period of sustainability will take a century or longer. Suggestions are made for measures needed to enhance the forest recovery. Keywords Forests - Shaanxi - West Virginia - Central China - Forest exploitation - Recovery CLC number S754 Document code A Article ID 1007-662X(2004)01-0049-06 Foundation item: The project was sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (2002–2004) and Shaanxi Provincial Foreign Expert Bureau (2003).Biography: Jack E. Coster (1935-), male, professor of West Virginia University, Morgantown, West Virginia. U.S.A.Responsible editor: Song Funan
基金Supported by the Financial from the U.S.Army Corps of Engineers-Lower Mississippi Valley Division,Vicksburg,Mississippi,U.S.A.
文摘The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Louisiana-Mississippi, U.S.A.) upstream to rkm 1504(Missouri-Kentucky, U.S.A.). Four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).Fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. Fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. Conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. Future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent secondary channels in selected river reaches. However, temporary secondary channels also contain unique fish species, and also appear to be important sites of riverine primary production. Restoration strategies should consider a balance of both secondary channel types, which should support the greatest biodiversity for the LMR ecosystem.
文摘In the U.S.Southwest,global climate change,acting in concert with extant stressors such as urbanization and over-allocation of water resources,is changing ecosystems in measureable and sometimes dramatic ways.Twenty-first century projections indicate accelerating climate change and cascading ecological consequences.Effects observed to date include large-scale forest dieback,large and severe wildfires,and changes in the flow regimes of rivers and streams with attendant changes to riparian and aquatic ecosystems.Rising temperatures and changing precipitation patterns are pushing ecosystems across physiological and ecological thresholds,causing widespread mortality and,in some cases,major changes in composition,structure and function.These changes have prompted action by the conservation community to reduce the adverse effects of climate change.The Southwest Climate Change Initiative(SWCCI),a project led by The Nature Conservancy,works with local stakeholders in affected landscapes,reduces adverse impacts on ecological and social systems using scientific knowledge and practical tools.The Initiative has learned through practical experience that: 1) managers must embrace change and manage for resilience rather than resistance;2) strong local science-management partnerships are critical to effective adaptation planning and implementation;3) planners and managers must broaden the scope and accelerate the pace of conservation activities if ecosystem services are to be sustained;4) adaptation often does not require radically new or different management practices,rather,conservationists already have many of the tools they need;and 5) rapid documentation and widespread communication of methods and findings can build rapidly regional capacity for climate change adaptation.Our experience suggests that adaptation efforts can be effective if they are focused at the local scale;employ learning networks;and engage in ecosystem-based adaptation:the sustainable management,conservation and restoration of ecosystems so that they continue to provide the services that allow people to thrive in changing environments.
文摘Use of hyperspectral spectroradiometers allows for information on different light bands to be captured, allowing for identification of plant health status. Apple scab is the most important disease in the production of apples. RIMpro is a web-based decision support system (DDS) for orchardists that has the capacity to improve optimal fungicide application for the control of apple scab and has the potential to reduce the number of applications and thereby reduce input expenses. The objective of this study was to complete a hyperspectral assessment of apple leaves in order to evaluate the spectral characteristics of trees sprayed according to forecasted infection events from the DDS. No significant differences in visual assessments or vegetation indices were observed between conventionally treated leaves and leaves treated according to the DSS. In the first year of this study two fungicide treatments were eliminated, in the second one fungicide treatment was eliminated. This finding is important because it provides evidence that plant health status is similar between conventionally sprayed trees and trees on a DSS-guided reduced spray program. In addition, the use of spectroradiometers for assessing the efficacy of different fungicide programs was demonstrated. Finally, potassium bicarbonate tank-mixed with sulfur was confirmed to be an effective spray material for managing apple scab. By integrating the precise information provided by DSSs and the use of biorational pesticides, agricultural producers, service providers and educators are able to adapt climate change considerations and action-oriented decisions into pest management plans.
文摘The fundamental reason for Sino-U.S.'trust deficit' is the narrowing of the gap between the two countries' national strengths and the subsequent change in U.S.policy.Especially the U.S.involvement in maritime disputes between China and her neighbors have further complicated bilateral relations.The two countries should make concerted efforts to improve cooperation and trust and seek to build a new type of great power relationship.
文摘This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland category comprised 17.7% of timber land area on all private and public lands in the South. This included 4.25 million ha of hydric sites;0.77 million ha mesic wet;9.55 million ha mesic, with only seasonal access;for a total of 14.57 million ha. The Natural Resource Inventory (NRI) for 2012 on private lands estimated that there were 14.71 million ha forested wetlands, which comprised 17.7% of all forested private forest area. The 2015 National Land Cover Data for the South estimated that there were 17.8 million ha of woody wetlands, which comprised 8% to 12% of the southern land area, and there were also 4.45 million ha of emergent herbaceous sites. About 10% of the southern timber forest sector would be based on harvests from wetland forests economy ($455 million per year), while the 17.7% of wetland land area would provide a proportional share of the annual nontimber forest products ($44 million) and payments for ecosystem services ($134 million). Wetlands also provide important nontimber forest products, and ecosystem services, which are beginning to develop active private and public markets.
文摘CHINESE President Xi Jinping and his U.S.counterpart Barack Obama resumed their round of meetings with their latest meeting at the end of September 2015.This was their third summit following their meetings at Sunnylands,California and evening talks at Yingtai,Beijing.If the week President Nixon spent in China was"a week that changed the world,"then the week during which President Xi paid a state visit to the U.S.and attended UN conferences may be called"a week that will shape the future."
文摘The U.S.bombing of Caracas,Venezuela,and kidnapping of its democratically elected president Nicolas Maduro in the early hours of January 3,of course,violated an international law regime that the U.S.Government has never had much respect for.Nonetheless,the openness of the discourse surrounding the U.S.'imperial bellicosity is novel in the modem era.
文摘Geopolitically,many in China longconsidered Latin America a distantregion-almost"the end of the Earth."That perception has changed dramatically.Over the past two decades,a steadilywarming relationship,driven largely by expanding commercial ties,has taken shape.
基金supported by the Chinese Action Plan for Journal Excellence:the sub-project of Selecting High-level Talents for Journal Publication-Youth Talents Project(2023ZZ050501).
文摘As two of the largest economies and countries in theworld,the People’sRepublic of China(China)and the United States of America(U.S.)both have enormous resources and innovative talents in a number of sectors.Cooperation between both sides will be hugely beneficial to the world population,and this is especially the case with healthcare.The U.S.-China Track II Dialogue on Healthcare was set up as a forum to discuss and engage ideas on this very topic.In this dialogue,Dr.Qun Yan,head of the hLife Editorial Office engages in a dialogue with Professor Mark McClellan,the Director of the Duke-Margolis Institute for Health Policy at Duke University and U.S.Co-Chair of the Track Ⅱ Dialogue on Healthcare,Professor Gordon G Liu,Professor at Peking University and the Dean of the PKU Institute for Global Health andDevelopment andCo-Organizer of the Track Ⅱ Dialogue,Mr.Stephen Orlins,President of the National Committee on U.S.-China Relations and a Co-Organizer of the Track Ⅱ Dialogue,and Professor George Fu Gao,Academician at the Chinese Academy of Sciences and formerDirector of the Chinese Center for Disease Control and Prevention.They discuss how and why the Track Ⅱ Dialogue was created,the successes and developments of the dialogues,and what the future of American-Chinese health collaboration looks like.
文摘Whenever U.S.Presibent Donald Trump talks about the U.S.fentanyl crisis,he will especially blame China for causing it That rhetoric does not hold up to scrutiny.At the beginning of this century,almost 800 Americans died from a fentanyl overdose.Fast forward to 2021.and more than 107,000 deaths were traced to the drug in that year alone.How is it possible that in roughly 20 years,the number of deaths had spiked over 13,000 percent?The answer is a complex one:Politicians are not interested in delivering such answers.Instead,they live in a world in which deflection and blaume generate headlines.And we know anytime a politician blames China that news covernage is soon to follow.
文摘I offer suggestions to increase the probability of success of an international research project.Collaborative studies often produce more innovative and transformative scientific results than work done by a single investigator or an isolated team.My advice is intended for early-career scientists.The product of the collaboration may be high-impact research publications,enhanced geophysical monitoring capabilities in a foreign country,or an advanced training course.Choosing the right international partner is the most important step.Keeping an open mind and being receptive to suggestions to modify the initial concept is critical.Other key steps include having a mutually agreed upon plan with achievable goals and well-defined expected outcomes.International cooperation is a richly rewarding experience that accelerates progress in the Earth Sciences.
基金supported by USDA-SCRI(Grant Nos.2017-51181-26830 and 2023-51181-41321)USDA-AMS SCMP(Grant No.16SCCMAR0001)+1 种基金Arkansas Department of Agriculture SCBGP(Grant No.AM22SCBGPAR1130-00)USDA NIFA Hatch project ARK0VG2018 and ARK02440.
文摘The Leafminers,representing a diverse group of insects from various genera within the Agromyzidae family,pose a significant threat to spinach(Spinacia oleracea L.)production.This study aimed to identify single nucleotide polymorphism(SNP)markers associated with leafminer resistance through a genome-wide association study(GWAS)and to evaluate the prediction accuracy(PA)for selecting resistant spinach using genomic prediction(GP).Using a dataset of 84301 SNPs obtained from whole-genome resequencing,seven GWAS models,including BLINK,FarmCPU,MLM,and MLMM in GAPIT 3,as well as MLM,GLM,and SMR in TASSEL 5,were employed to perform GWAS on a panel of 286 USDA spinach germplasm accessions.Three SNP markers,namely 1_115279256_C_T,3_157082529_C_T,and 4_168510908_T_G on chromosomes 1,3,and 4,respectively,were identified as associated with leafminer resistance.In the 30 kb flanking regions of these markers,four candidate genes(SOV1g031330,SOV1g031340,SOV4g047270,and SOV4g047280),encoding LOB domain-containing protein,KH domain-containing protein,were discovered.Nodulin-like domain-containing protein,and SAM domain-containing protein,were discovered.The PA for leafminer resistance selection was estimated using ten different SNP sets,including two GWAS-derived marker sets(three and 51 SNPs)and eight random marker sets(ranging from 51 to 10 K SNPs)analyzed by seven GP models.The findings emphasized the superior performance of GWAS-derived SNP sets,reaching a PA of up to 0.79 using the cBLUP model.Notably,this research marks the pioneering application of GP in the context of insect resistance,providing a significant advancement in the understanding and management of leafminer resistance in spinach cultivation.
文摘Acute exposure to high altitude can cause acute altitude illnesses and is associated with impaired cognitive and physical performance.The most effective preventive strategies currently recommended include environmental acclimatization(slow ascent and/or pre-acclimatization)or pharmacological support of acclimatization using acetazolamide.However,these strategies are not practical for high-altitude exposures that require rapid and unplanned ascent,high physical and mental performance,such as rescue missions or military operations.Dexamethasone and other modulators of the glucocorticoid system take effect quickly and are effective alternatives for preventing acute altitude illnesses when rapidly ascending to high altitudes.As the efficacy of dexamethasone in preventing acute mountain illnesses remains controversial,a review of existing studies on the use of dexamethasone for the prevention of acute mountain sickness was conducted,aiming to determine the best strategy.Possible mechanisms of protection against acute altitude illnesses are discussed based on the results of clinical trials.The data indicate that dexamethasone is most effective at altitudes above 4000 m at doses of 8–16 mg/d.Appropriately designed and powered trials are needed to obtain more evidence-based results on the dosage and timing of dexamethasone administration,and to provide optimized recommendations for the application of this powerful pharmacological tool.
文摘For many years, coal-fired power plant generation comprised the largest share of electricity in the U.S.power sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain a shrinking but significant component of U.S. electricity production. Natural gas-fired technologies are dispatchable and versatile generation sources, but the recent and anticipated growth of wind and solar technologies will add nondispatchable, intermittent power generation sources to U.S.electricity grids. Numerous emissions-related benefits arise from the deployment of these technologies, but they must coexist with coal plants, many of which run most efficiently under baseload operating procedures. Historical monthly emissions data has been analyzed on a sample of coal plants to show how modified coal operations have affected plant emission rates, as measured by carbon dioxide emitted per unit of electricity output. Statistically significant correlations between plant capacity factors and emission rate intensity have been observed by the majority of the sample, showing a worsening under more sporadic operations. Since nearly all of the coal plants in the sample are generating less electricity, determining the emission impact of operational decisions will assist policymakers as they seek to minimize total system emissions without severe disruptions to electricity cost and service reliability.
