Load-Unload Response Ratio (LURR) is a new promising approach to earthquake prediction. In the previous years, a series of successful medium-term predictions have been made for strong earthquakes on the Chinese mainla...Load-Unload Response Ratio (LURR) is a new promising approach to earthquake prediction. In the previous years, a series of successful medium-term predictions have been made for strong earthquakes on the Chinese mainland using this method. In order to investigate whether the LURR method applies to different tectonic regimes, i.e., whether it is universal, the San Andreas Fault and its vicinities are chosen as the study region in this paper. The spatial variation of LURR in the western United States (30°～50°N, 100°～130°W) is studied in detail and the earthquake tendency in this region is discussed based on historic earthquake cases.展开更多
Background:The coronavirus disease 2019(COVID-19)became a global pandemic within several months after it was first reported at the end of December,2019.Countries in the Northern Hemisphere have been affected the most,...Background:The coronavirus disease 2019(COVID-19)became a global pandemic within several months after it was first reported at the end of December,2019.Countries in the Northern Hemisphere have been affected the most,including the United States and European countries.Contrary to the common knowledge that infectious diseases are more prevalent in low-and middle-income countries,COVID-19 appears to affect wealthy countries more.This paper attempts to quantify the relationship between COVID-19 infections and levels of economic development with data from the U.S.and Europe.Methods:Public domain data on the confirmed COVID-19 cases during January 1 and May 31,2020 by states and territories in the U.S.and by countries in Europe were included.Incidence rate was estimated using the 2019 total population.COVID-19 cases were associated with 2019 gross domestic product(GDP)using regression models after a logarithmic transformation of the data.The U.S.data and European data were analyzed separately,considering significant heterogeneity between the two.Results:A total of 2451691 COVID-19 cases during a 5-month period were analyzed,including 1787414 from 50 U.S.states and territories and 664277 from 28 European countries.The overall incidence rate was 5.393/1000 for the U.S.and 1.411/1000 for European countries with large variations.Lg(total cases)was significantly associated with lg(GDP)for U.S.states(=1.2579,P<0.001)and European countries(=0.7156,P<0.001),respectively.Conclusion:This study demonstrated a positive correlation between COVID-19 case incidence and GDP in the United States and 28 European countries.Study findings suggest a potential role of high-level development in facilitating infectious disease spread,such as more advanced transportation system,large metropolitan cities with high population density,better domestic and international travel for businesses,leisure,and more group activities.These factors must be considered in controlling the COVID-19 epidemic.This study focuses on the impact of economic development,many other factors might also have contributed to the rapid spread of COVID-19 in these countries and states,such as differences in national and statewide anti-epidemic strategies,people's behavior,and healthcare systems.Besides,low-and middle-income countries may have an artificially low COVID-19 case count just due to lack of diagnostic capabilities.Findings of this study also encourage future research with individual-level data to detect risk factors at the personal level to understand the risk of COVID-19.展开更多
Anthropogenic Nitrogen oxides(NO_(x)=NO_(2)+NO)emissions are highly concentrated in urban area,and the weekly cycles,seasonal patterns and long-term trends of tropospheric NO_(2) columns over cities differ from region...Anthropogenic Nitrogen oxides(NO_(x)=NO_(2)+NO)emissions are highly concentrated in urban area,and the weekly cycles,seasonal patterns and long-term trends of tropospheric NO_(2) columns over cities differ from region to region due to different emission sectoral compositions and human activities.In this study,we used satellite observed tropospheric NO_(2) column data to compare the longand short-term NO_(2) column density time series over cities in the United Sates(the U.S.),western Europe and China.The results showed that in all the targeted cities,the outbreak of the Corona Virus Disease in 2019(COVID-19)moved the December peak of the city-level NO_(2)columns forward to November and October or even earlier in 2020 and 2021.On weekly level,cities in the U.S.show the lowest NO_(2) columns ratio on weekend/work day,then come the western European cities,and a weak weekly pattern is seen in Chinese cities.For all the cites,we find a higher weekend/work day NO_(2) ratio in cold seasons than in warm seasons,indicating a higher contribution from NOx emission sectors of residential,industry and power plants in the warm seasons.In the long-term,NO_(2) columns over the U.S.and western European cities declined by a fraction twice that of the regional mean level from 2004 to 2021.In China,NO_(2) columns started to decrease since 2012,at a similar rate between the city and regional level.This work confirms the importance to quantify and control NOx emissions from cities.展开更多
Purpose： In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States （PNAS） with re...Purpose： In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States （PNAS） with regard to two levels： journal and country. Design/methodology/approach： Using relative values based on fractional counting, we investigate the distribution of publications across document types at both the journal and country level, and we use （cosine） document type profile similarity values to compare pairs of publication years within countries. Findings： Nature and Science mainly publish Editorial Material, Article, News Item and Letter, whereas the publications of PNAS are heavily concentrated on Article. The shares of Article for Nature and Science are decreasing slightly from 1999 to 2014, while the corresponding shares of Editorial Material are increasing. Most studied countries focus on Article and Letter in Nature, but on Letter in Science and PNAS. The document type profiles of some of the studied countries change to a relatively large extent over publication years. Research limitations： The main limitation of this research concerns the Web of Science classification of publications into document types. Since the analysis of the paper is based on document types of Web of Science, the classification in question is not free from errors, and the accuracy of the analysis might be affected.Practical implications： Results show that Nature and Science are quite diversified with regard to document types. In bibliometric assessments, where publications in Nature and Science play a role, other document types than Article and Review might therefore be taken into account. Originality/value： Results highlight the importance of other document types than Article and Review in Nature and Science. Large differences are also found when comparing the country document type profiles of the three journals with the corresponding profiles in all Web of Science journals.展开更多
Pakistan,China’s all-weather strategic cooperative partner,has recently undergone a significant adjustment in its major country diplomacy,particularly in its policies toward the United States and Russia.The triangula...Pakistan,China’s all-weather strategic cooperative partner,has recently undergone a significant adjustment in its major country diplomacy,particularly in its policies toward the United States and Russia.The triangular relationship among Pakistan,the United States,and Russia has changed from a previous severely unbalanced state,in which the Pakistan–United States relationship is stronger and the Pakistan–Russia relationship is weaker,to a relatively dynamic equilibrium state in which the Pakistan–United States relationship declines while the Pakistan–Russia relationship rises.At the same time,although Pakistan’s policy toward India and China has continued the central tone of Pakistan–India confrontation and Pakistan–China friendship,several new changes and trends have emerged.While Pakistan–India relations are generally tense,Pakistan has performed active management of crises to keep conflicts from getting out of control and leading to war or other combat.Pakistan has long actively maintained friendly relations with China and is focusing on promoting practical cooperation in the form of the China–Pakistan Economic Corridor.The current round of adjustment to Pakistan’s major country diplomacy stems from multiple internal and external factors.Externally,the United States has begun to promote its“Indo-Pacific”strategy,and the Ukraine crisis has played a catalytic role as well.Internally,these changes can mainly be ascribed to the major changes in Pakistan’s leadership,as well as the country’s severe domestic political and economic challenges,as well as the urgent need for external support,especially from major countries,to improve the domestic situation.Pakistan’s major country diplomacy adjustment has had relatively obvious geopolitical and security impacts so far at the global and regional levels,but it is limited by the international situation,its own strategic orientation,and national conditions.Pakistan’s relations with major countries continue to face structural challenges.展开更多
以美国西部3个著名的国家公园(黄石、洛基山和大峡谷)及其缓冲区为研究对象,以空间分辨率30m的3期美国国家土地覆盖数据库(National Land Cover Databases,NLCD 1992\2001\2006)为数据源,采用森林破碎化分析模型与景观指数相结合的方法...以美国西部3个著名的国家公园(黄石、洛基山和大峡谷)及其缓冲区为研究对象,以空间分辨率30m的3期美国国家土地覆盖数据库(National Land Cover Databases,NLCD 1992\2001\2006)为数据源,采用森林破碎化分析模型与景观指数相结合的方法刻画国家公园及其缓冲区内森林破碎化及干扰模式的时空差异,并有效分离导致森林破碎化的人为干扰和自然干扰贡献份额。结果表明:美国西部国家公园内森林因严格保护而破碎化程度较低且森林状态保持稳定,主要的干扰形式是自然干扰并伴有少量的城市土地利用类型的空间交互。而在缓冲区,由于存在相对宽松的森林经营活动森林破碎化程度较高,森林受自然干扰和人为干扰共同作用,其中农业土地利用扮演主要角色。这些差异主要归因于美国西部陡峻的地形、土地所有权及民众的生活方式。为了有效改善中国森林及国家公园的管理水平,可充分借鉴美国国家公园管理过程中的先进的经营理念、法律依据、管理机制、资金机制和监督机制等,并应在森林经营实践中确保森林保护政策有效执行。展开更多
文摘Load-Unload Response Ratio (LURR) is a new promising approach to earthquake prediction. In the previous years, a series of successful medium-term predictions have been made for strong earthquakes on the Chinese mainland using this method. In order to investigate whether the LURR method applies to different tectonic regimes, i.e., whether it is universal, the San Andreas Fault and its vicinities are chosen as the study region in this paper. The spatial variation of LURR in the western United States (30°～50°N, 100°～130°W) is studied in detail and the earthquake tendency in this region is discussed based on historic earthquake cases.
文摘Background:The coronavirus disease 2019(COVID-19)became a global pandemic within several months after it was first reported at the end of December,2019.Countries in the Northern Hemisphere have been affected the most,including the United States and European countries.Contrary to the common knowledge that infectious diseases are more prevalent in low-and middle-income countries,COVID-19 appears to affect wealthy countries more.This paper attempts to quantify the relationship between COVID-19 infections and levels of economic development with data from the U.S.and Europe.Methods:Public domain data on the confirmed COVID-19 cases during January 1 and May 31,2020 by states and territories in the U.S.and by countries in Europe were included.Incidence rate was estimated using the 2019 total population.COVID-19 cases were associated with 2019 gross domestic product(GDP)using regression models after a logarithmic transformation of the data.The U.S.data and European data were analyzed separately,considering significant heterogeneity between the two.Results:A total of 2451691 COVID-19 cases during a 5-month period were analyzed,including 1787414 from 50 U.S.states and territories and 664277 from 28 European countries.The overall incidence rate was 5.393/1000 for the U.S.and 1.411/1000 for European countries with large variations.Lg(total cases)was significantly associated with lg(GDP)for U.S.states(=1.2579,P<0.001)and European countries(=0.7156,P<0.001),respectively.Conclusion:This study demonstrated a positive correlation between COVID-19 case incidence and GDP in the United States and 28 European countries.Study findings suggest a potential role of high-level development in facilitating infectious disease spread,such as more advanced transportation system,large metropolitan cities with high population density,better domestic and international travel for businesses,leisure,and more group activities.These factors must be considered in controlling the COVID-19 epidemic.This study focuses on the impact of economic development,many other factors might also have contributed to the rapid spread of COVID-19 in these countries and states,such as differences in national and statewide anti-epidemic strategies,people's behavior,and healthcare systems.Besides,low-and middle-income countries may have an artificially low COVID-19 case count just due to lack of diagnostic capabilities.Findings of this study also encourage future research with individual-level data to detect risk factors at the personal level to understand the risk of COVID-19.
基金Under the auspices of the National Natural Science Foundation of China(No.42375106,41805098)the National Key R&D Program of China(No.2023YFB3907500)。
文摘Anthropogenic Nitrogen oxides(NO_(x)=NO_(2)+NO)emissions are highly concentrated in urban area,and the weekly cycles,seasonal patterns and long-term trends of tropospheric NO_(2) columns over cities differ from region to region due to different emission sectoral compositions and human activities.In this study,we used satellite observed tropospheric NO_(2) column data to compare the longand short-term NO_(2) column density time series over cities in the United Sates(the U.S.),western Europe and China.The results showed that in all the targeted cities,the outbreak of the Corona Virus Disease in 2019(COVID-19)moved the December peak of the city-level NO_(2)columns forward to November and October or even earlier in 2020 and 2021.On weekly level,cities in the U.S.show the lowest NO_(2) columns ratio on weekend/work day,then come the western European cities,and a weak weekly pattern is seen in Chinese cities.For all the cites,we find a higher weekend/work day NO_(2) ratio in cold seasons than in warm seasons,indicating a higher contribution from NOx emission sectors of residential,industry and power plants in the warm seasons.In the long-term,NO_(2) columns over the U.S.and western European cities declined by a fraction twice that of the regional mean level from 2004 to 2021.In China,NO_(2) columns started to decrease since 2012,at a similar rate between the city and regional level.This work confirms the importance to quantify and control NOx emissions from cities.
基金supported by the National Natural Science Foundation of China(Grant No.:L1524037)
文摘Purpose： In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States （PNAS） with regard to two levels： journal and country. Design/methodology/approach： Using relative values based on fractional counting, we investigate the distribution of publications across document types at both the journal and country level, and we use （cosine） document type profile similarity values to compare pairs of publication years within countries. Findings： Nature and Science mainly publish Editorial Material, Article, News Item and Letter, whereas the publications of PNAS are heavily concentrated on Article. The shares of Article for Nature and Science are decreasing slightly from 1999 to 2014, while the corresponding shares of Editorial Material are increasing. Most studied countries focus on Article and Letter in Nature, but on Letter in Science and PNAS. The document type profiles of some of the studied countries change to a relatively large extent over publication years. Research limitations： The main limitation of this research concerns the Web of Science classification of publications into document types. Since the analysis of the paper is based on document types of Web of Science, the classification in question is not free from errors, and the accuracy of the analysis might be affected.Practical implications： Results show that Nature and Science are quite diversified with regard to document types. In bibliometric assessments, where publications in Nature and Science play a role, other document types than Article and Review might therefore be taken into account. Originality/value： Results highlight the importance of other document types than Article and Review in Nature and Science. Large differences are also found when comparing the country document type profiles of the three journals with the corresponding profiles in all Web of Science journals.
文摘Pakistan,China’s all-weather strategic cooperative partner,has recently undergone a significant adjustment in its major country diplomacy,particularly in its policies toward the United States and Russia.The triangular relationship among Pakistan,the United States,and Russia has changed from a previous severely unbalanced state,in which the Pakistan–United States relationship is stronger and the Pakistan–Russia relationship is weaker,to a relatively dynamic equilibrium state in which the Pakistan–United States relationship declines while the Pakistan–Russia relationship rises.At the same time,although Pakistan’s policy toward India and China has continued the central tone of Pakistan–India confrontation and Pakistan–China friendship,several new changes and trends have emerged.While Pakistan–India relations are generally tense,Pakistan has performed active management of crises to keep conflicts from getting out of control and leading to war or other combat.Pakistan has long actively maintained friendly relations with China and is focusing on promoting practical cooperation in the form of the China–Pakistan Economic Corridor.The current round of adjustment to Pakistan’s major country diplomacy stems from multiple internal and external factors.Externally,the United States has begun to promote its“Indo-Pacific”strategy,and the Ukraine crisis has played a catalytic role as well.Internally,these changes can mainly be ascribed to the major changes in Pakistan’s leadership,as well as the country’s severe domestic political and economic challenges,as well as the urgent need for external support,especially from major countries,to improve the domestic situation.Pakistan’s major country diplomacy adjustment has had relatively obvious geopolitical and security impacts so far at the global and regional levels,but it is limited by the international situation,its own strategic orientation,and national conditions.Pakistan’s relations with major countries continue to face structural challenges.
文摘以美国西部3个著名的国家公园(黄石、洛基山和大峡谷)及其缓冲区为研究对象,以空间分辨率30m的3期美国国家土地覆盖数据库(National Land Cover Databases,NLCD 1992\2001\2006)为数据源,采用森林破碎化分析模型与景观指数相结合的方法刻画国家公园及其缓冲区内森林破碎化及干扰模式的时空差异,并有效分离导致森林破碎化的人为干扰和自然干扰贡献份额。结果表明:美国西部国家公园内森林因严格保护而破碎化程度较低且森林状态保持稳定,主要的干扰形式是自然干扰并伴有少量的城市土地利用类型的空间交互。而在缓冲区,由于存在相对宽松的森林经营活动森林破碎化程度较高,森林受自然干扰和人为干扰共同作用,其中农业土地利用扮演主要角色。这些差异主要归因于美国西部陡峻的地形、土地所有权及民众的生活方式。为了有效改善中国森林及国家公园的管理水平,可充分借鉴美国国家公园管理过程中的先进的经营理念、法律依据、管理机制、资金机制和监督机制等,并应在森林经营实践中确保森林保护政策有效执行。
