The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to en...The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management.展开更多
Nephrolithiasis is increasing in developed and developing countries at an alarming rate. With the global spike in kidney stone diseases, it is crucial to determine what risk factors are influencing the current global ...Nephrolithiasis is increasing in developed and developing countries at an alarming rate. With the global spike in kidney stone diseases, it is crucial to determine what risk factors are influencing the current global landscape for kidney stones. Our aims for this review are: to identity and analyze the four categories of risk factors in contributing to the global scale of stone formation: lifestyle, genetics, diet, and environment; and discuss preventative measures for kidney stone formation. We also performed data search through the published scientific literature, i.e., PubMed~? and found that there is a significant link between lifestyle and obesity with cases of calcium stones. Food and Agriculture Organization of the United Nations and World Health Organization factor indicators for dietary intake and obesity, along with climate data were used to create the projected total risk world map model for nephrolithiasis risk. Complete global analyses of nephrolithiasis deplete of generalizations is nearly insurmountable due to limited sources of medical and demographic information, but we hope this review can provide further elucidation into confounding risk factors and preventative measures for global nephrolithiasis analysis.展开更多
This study investigates the asymmetric relationship between global and national fac-tors and domestic food prices in Turkey,considering the recent rapid and continuous increase in domestic food prices.In this context,...This study investigates the asymmetric relationship between global and national fac-tors and domestic food prices in Turkey,considering the recent rapid and continuous increase in domestic food prices.In this context,six global and three national explana-tory variables were included,and monthly data for the period from January 2004 to June 2021 were used.In addition,novel nonlinear time-series econometric approaches,such as wavelet coherence,Granger causality in quantiles,and quantile-on-quantile regression,were applied for examination at different times,frequencies,and quan-tiles.Moreover,the Toda-Yamamoto(TY)causality test and quantile regression(QR)approach were used for robustness checks.The empirical results revealed that(i)there is a significant relationship between domestic food prices and explanatory variables at different times and frequencies;(ii)a causal relationship exists in most quantiles,excluding the lowest quantile,some middle quantiles,and the highest quantile for some variables;(iii)the power of the effect of the explanatory variables on domestic food prices varies according to the quantiles;and(iv)the results were validated by the TY causality test and QR,which show that the results were robust.Overall,the empiri-cal results reveal that global and national factors have an asymmetric relationship with domestic food prices,highlighting the effects of fluctuations in global and national variables on domestic food prices.Thus,the results imply that Turkish policymakers should consider the asymmetric effects of global and national factors on domestic food prices at different times,frequencies,and quantiles.展开更多
This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Mete...This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69oN,Longitude 86.73?E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R2) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available.展开更多
目的分析1990—2021年中国与全球早发女性乳腺癌的疾病负担、变化趋势及归因风险因素。方法从全球疾病负担(Global Burden of Disease,GBD)2021数据库提取1990—2021年中国与全球早发女性乳腺癌(诊断年龄<50岁)的发病、死亡和伤残调...目的分析1990—2021年中国与全球早发女性乳腺癌的疾病负担、变化趋势及归因风险因素。方法从全球疾病负担(Global Burden of Disease,GBD)2021数据库提取1990—2021年中国与全球早发女性乳腺癌(诊断年龄<50岁)的发病、死亡和伤残调整生命年(disability adjusted life years,DALYs)的绝对值和粗率,提取5种风险因素(吸烟、饮酒、低体力活动、高红肉饮食、高空腹血糖)和全部风险因素的DALYs归因占比数据。采用Joinpoint回归模型,以年度变化百分比(annual percentage change,APC)和平均年度变化百分比(average annual percentage change,AAPC)分析标化率的变化趋势。结果1990—2021年,中国和全球早发女性乳腺癌标化发病率均呈整体上升趋势(中国:AAPC=2.25%;全球:AAPC=0.64%;成对比较,P<0.001),标化死亡率(中国:AAPC=-0.82%;全球:AAPC=-0.26%;成对比较,P<0.001)和标化DALYs率(中国:AAPC=-0.63%;全球:AAPC=-0.18%;成对比较,P=0.004)均呈整体下降趋势。2021年中国和全球标化发病率分别为13.49/10万和13.61/10万,标化死亡率分别为1.99/10万和3.14/10万。中国标化死亡率(APC=0.78%)和标化DALYs率(APC=1.38%)分别在2014年和2015年呈逐渐上升趋势。2021年,中国(13.55%)与全球(11.20%)早发女性乳腺癌DALYs归因于高红肉饮食的比例均相对最高。结论中国早发女性乳腺癌标化发病率增长迅速,正向全球整体水平靠近,标化死亡率和标化DALYs率在近十余年均呈上升趋势,防治形势依然严峻。未来应进一步扩大乳腺癌筛查项目的推广范围,优化乳腺癌筛查方案,提高居民癌症防治知识水平,以减轻中国日益增长的早发女性乳腺癌疾病负担。展开更多
基金supported by the National Natural Science Foundation of China(No.42030509)the Special Project on National Science and Technology Basic Resources Investigation of China(No.2021FY100705).
文摘The leaf nitrogen(N)to phosphorus(P)ratio(N:P)is a critical indicator of nutrient dynamics and ecosystem function.Investigating temporal variations in leaf N:P can provide valuable insights into how plants adapt to environmental changes and nutrient availability.However,limited research has been conducted on long-term temporal leaf N:P variation over a range of temperature zones.Using long-term monitoring data from the Chinese Ecosystem Research Network(CERN),we investigated temporal changes in leaf N and P stoichiometry for 50 dominant tree species from 10 typical forest sites across temperate and subtropical regions,and identified the underlying mechanisms driving these changes.For both regions combined,leaf P concentration of the 50 dominant tree species decreased(20.6%),whereas leaf N:P increased(52.0%)from 2005 to 2020.Leaf P decreased and leaf N:P increased in 67% and 69% of the tree species,respectively.The leaf N:P increase was primarily driven by the tree species in eastern subtropical forests,where global change factors and soil nutrients explained 68% of leaf N:P variation.The P limitation exhibited by tree species in eastern subtropical forest ecosystems intensified over time,and elevated temperature and CO_(2) levels,coupled with decreased soil available P concentrations,appear to be the main factors driving long-term leaf N:P increases in these forests.Investigating long-term variations in soil nutrients together with global change factors will improve our understanding of the nutrient status of forest ecosystems in the context of global change and will support effective forest ecosystem management.
基金Supported by National Institute of Diabetes and Digestive and Kidney Diseases,No.DK102043(to Bidhan C Bandyopadhyay)National Institute of Biomedical Imaging and Bioengineering,No.EB021483(to Bidhan C Bandyopadhyay)
文摘Nephrolithiasis is increasing in developed and developing countries at an alarming rate. With the global spike in kidney stone diseases, it is crucial to determine what risk factors are influencing the current global landscape for kidney stones. Our aims for this review are: to identity and analyze the four categories of risk factors in contributing to the global scale of stone formation: lifestyle, genetics, diet, and environment; and discuss preventative measures for kidney stone formation. We also performed data search through the published scientific literature, i.e., PubMed~? and found that there is a significant link between lifestyle and obesity with cases of calcium stones. Food and Agriculture Organization of the United Nations and World Health Organization factor indicators for dietary intake and obesity, along with climate data were used to create the projected total risk world map model for nephrolithiasis risk. Complete global analyses of nephrolithiasis deplete of generalizations is nearly insurmountable due to limited sources of medical and demographic information, but we hope this review can provide further elucidation into confounding risk factors and preventative measures for global nephrolithiasis analysis.
基金from funding agencies in the public,commercial,or not-for-profit sectors.
文摘This study investigates the asymmetric relationship between global and national fac-tors and domestic food prices in Turkey,considering the recent rapid and continuous increase in domestic food prices.In this context,six global and three national explana-tory variables were included,and monthly data for the period from January 2004 to June 2021 were used.In addition,novel nonlinear time-series econometric approaches,such as wavelet coherence,Granger causality in quantiles,and quantile-on-quantile regression,were applied for examination at different times,frequencies,and quan-tiles.Moreover,the Toda-Yamamoto(TY)causality test and quantile regression(QR)approach were used for robustness checks.The empirical results revealed that(i)there is a significant relationship between domestic food prices and explanatory variables at different times and frequencies;(ii)a causal relationship exists in most quantiles,excluding the lowest quantile,some middle quantiles,and the highest quantile for some variables;(iii)the power of the effect of the explanatory variables on domestic food prices varies according to the quantiles;and(iv)the results were validated by the TY causality test and QR,which show that the results were robust.Overall,the empiri-cal results reveal that global and national factors have an asymmetric relationship with domestic food prices,highlighting the effects of fluctuations in global and national variables on domestic food prices.Thus,the results imply that Turkish policymakers should consider the asymmetric effects of global and national factors on domestic food prices at different times,frequencies,and quantiles.
文摘This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69oN,Longitude 86.73?E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R2) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available.
