AIM:To investigate time trends in myopia and high myopia prevalence over 6y among young university adults in China.METHODS:This is a 6-year series cross-sectional study from 2016 to 2021.Totally 4910 freshmen were enr...AIM:To investigate time trends in myopia and high myopia prevalence over 6y among young university adults in China.METHODS:This is a 6-year series cross-sectional study from 2016 to 2021.Totally 4910 freshmen were enrolled and completed a questionnaire concerning age,gender,and disease history.Students with eye diseases were excluded after a detailed eye examination.The refractive status was measured by non-cycloplegic objective refraction and ocular parameters were measured by Lenstar 900.The examination followed the same protocol each year.Trends over time in myopia and high myopia prevalence,as well as ocular biometry parameters,were analyzed.RESULTS:From 2016 to 2021,the axial length(AL)and corneal radius(CR)increased significantly(P=0.002 for AL;P=0.04 for CR).However,the spherical equivalent(SE)and the ratio of axial length to the corneal radius(AL/CR)did not change significantly(P=0.59 for SE;P=0.24 for AL/CR).The frequency of AL≥26.0 mm increased from 26.6%in 2016 to 29.3%in 2021(P=0.05 for trend).The prevalence of myopia and high myopia did not change significantly in our study(P≥0.18).Compared to a similar cross-sectional study conducted 10 years ago,the prevalence of myopia decreased significantly(94.9%vs 91.8%,P<0.001).Whereas the prevalence of high myopia increased largely(18.12%vs 27.6%,P<0.001).CONCLUSION:The prevalence of high myopia increases in young university adults during 10y period.Myopia control should begin earlier in childhood.However,these interventions are still needed for high myopia even in young adulthood.展开更多
Background: Currently, surgical resection represents the only curative treatment for pancreatic cancer(PC), however, the majority of tumors are no longer resectable by the time of diagnosis. The aim of this study was ...Background: Currently, surgical resection represents the only curative treatment for pancreatic cancer(PC), however, the majority of tumors are no longer resectable by the time of diagnosis. The aim of this study was to describe time trends and distribution of pancreaticoduodenectomies(PDs) performed for treating PC in Brazil in recent years. Methods: Data were retrospectively obtained from Brazilian Health Public System(namely DATASUS) regarding hospitalizations for PC and PD in Brazil from January 2008 to December 2015. PC and PD rates and their mortalities were estimated from DATASUS hospitalizations and analyzed for age, gender and demographic characteristics. Results: A total of 2364 PDs were retrieved. Albeit PC incidence more than doubled, the number of PDs increased only 37%. Most PDs were performed in men(52.2%) and patients between 50 and 69 years old(59.5%). Patients not surgically treated and those 70 years or older had the highest in-hospital mortality rates. The most developed regions(Southeast and South) as well as large metropolitan integrated municipalities registered 76.2% and 54.8% of the procedures, respectively. LMIM PD mortality fluctuated, ranging from 13.6% in 2008 to 11.8% in 2015. Conclusions: This study suggests a trend towards regionalization and volume-outcome relationships for PD due to PC, as large metropolitan integrated municipalities registered most of the PDs and more stable mortality rates. The substantial differences between PD and PC increasing rates reveals a limiting step on the health system resoluteness. Reduction in the number of hospital beds and late access to hospitalization, despite improvement in diagnostic methods, could at least in part explain these findings.展开更多
Adequate dietary zinc intake remains a public health challenge in China.Also,there is a lack of information on the relationship between Zn intake and food consumption patterns across provinces and over time.In this st...Adequate dietary zinc intake remains a public health challenge in China.Also,there is a lack of information on the relationship between Zn intake and food consumption patterns across provinces and over time.In this study,data from the China Health and Nutrition Survey 2004-2011(21,266 individuals)was used to explore associations between dietary Zn intake and sociodemographic factors.Zn intake per person declined from 11.1 mg·d^(-1)in 2004 to 9.89 mg·d^(-1)in 2011,with reduction in cereal consumption the greatest contributor to this.However,the reduction resulting from the lower cereal consumption was only partly compensated by an increase in consumption of Zn-rich foods.The percentage of the study population with inadequate Zn intake increased from 23% in 2004 to 37% in 2011.While Zn intake was positively associated with income levels in each survey year,the time trend for all income levels was a gradually reducing Zn intake.In all years,males had an average higher dietary Zn intake,whereas no significant difference was found between living areas.In conclusion,this study shows that dietary Zn inadequacy was high and has increased over the studied period.Remediation could be sought by shifting dietary patterns toward more Zn-dense food or by enhancing Zn concentration through biofortification.展开更多
BACKGROUND Relative changes in the prevalence of gastrointestinal(GI)diseases have been reported worldwide over the past decades.However,data on changing trends of upper GI diseases remain scarce in sub-Saharan Africa...BACKGROUND Relative changes in the prevalence of gastrointestinal(GI)diseases have been reported worldwide over the past decades.However,data on changing trends of upper GI diseases remain scarce in sub-Saharan Africa.This study examines the shifting patterns of upper GI endoscopic findings over 35 years in Ethiopia.AIM To analyze trends in upper GI endoscopic findings over two distinct time periods,35 years apart,in Ethiopia.METHODS We extracted findings from 8412 upper GI endoscopies performed between 2016 and 2024 at a tertiary referral center in Addis Ababa,Ethiopia.Patient characteristics,indications,and endoscopic findings were analyzed using descriptive statistics and presented in tables,map and graphs.These findings were compared to 10000 procedures conducted between 1979 and 1994.Key endoscopic findings were identified,and percentage changes in disease prevalence were calculated.RESULTS Between the two study periods,the male-to-female ratio of patients undergoing upper GI endoscopy shifted from 2:1 to 1.4:1,while the median patient age increased from 36 to 40 years.The proportion of patients older than 50 years doubled(14.6%to 30.2%),and referrals from outside Addis Ababa increased from 33%to 57%.The prevalence of peptic ulcer disease and its complications decreased from 46.2%to 9.5%.Conversely,gastroesophageal varices increased from 9.5%to 21.8%,and upper GI malignancies rose from 3.6%to 18.8%.CONCLUSION This study sheds light on critical epidemiological shifts in upper GI diseases in Ethiopia,with a decline in peptic ulcer disease and a rise in portal hypertensive lesions and malignancies which have important public health implications.These findings underscore the need for increased awareness,improved clinical practices,enhanced resource allocation,and expanded access to early diagnosis and treatment of prevailing conditions.Preventive strategies targeting immunization and treatment of viral hepatitis,schistosomiasis,and Helicobacter pylori infection are urgently needed.展开更多
Background:The epidemiological investigation of Hodgkin’s lymphoma(HL)among the genetically peculiar population of the Italian island of Sardinia might provide interesting etiological clues.Methods:We used the databa...Background:The epidemiological investigation of Hodgkin’s lymphoma(HL)among the genetically peculiar population of the Italian island of Sardinia might provide interesting etiological clues.Methods:We used the database of 1974-2003 incident cases of hematological malignancies in Sardinia and Bayesian methods to explore the time trend and geographic spread of HL incidence by sex,and age whether≤44 or≥45 years.We also tested its association with several socio-economic and environmental risk factors.Results:The age-and sex-standardized(world population)incidence rate of HL was 2.6 per 100,000(95%CI,2.5-2.8).Over the study period,HL incidence increased linearly in both sexes and among those aged≤44 years but not above that age.Cases clustered among young women in a central-western area covering four bordering administrative units(13 cases vs.5.7 expected,P=0.002).The posterior probability of excess HL cases aged≤44 years was elevated only in a commune in the suburban area of the region’s capital.Cases aged≥45 years were uniformly spread over the region.Among the risk factors we explored,urban residence was associated with an elevated and goat farming with a decreased risk of HL occurrence.We did not observe a link with socio-economic deprivation,environmental exposures,or multiple sclerosis.The geographic spread of COVID-19 was also unrelated to past HL incidence.Conclusions:Our results prompt further in-depth investigation into the previously undetected cluster and the nature of the observed associations.展开更多
The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyse...The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyses (Fourier series analysis, t-test, and Mann-Kendall test). The stations were spatially divided into three regions: northwest (NW), southwest (SW), and southeast (SE) to evaluate spatial variability in temperature. The results of the study reveal that the annual maximum mean temperature showed increasing trend for NW, and mixed trends for SW and SE regions. The variability was found to be more for northern stations as compared to southern stations for annual extreme minimum temperature. In addition, the trend slope per 100 years for the average annual extreme minimum temperature increased within the range of -0.8°C (Stratford) to 15°C (Porcupine). The seasonal analysis demonstrated that extreme maximum temperature has an increasing trend and maximum mean temperature has a decreasing trend during summer and winter. The extreme minimum temperature for winter illustrated an increasing trend (90%) with 22% statistically significant for NW region. For the SW region, the trend is also increasing (80%) for most of the temperature variables and 25% of temperature data were significantly increased in the SW region. The SE region stations showed overall very clear increasing trends (95%) for all the temperature variables. The data also showed that 47% of data were statistically significant in the SE region. The analysis of variance accounted for by trend, significant periodicities, and random component show that the pattern is similar for the percent of variance accounted for periodicities, and random component contribute dominantly for the four temperature variables and frost free days (FFD) for all three regions. Overall, the study reveals that the extreme minimum temperature is increasing annually and seasonally, with statistically significant at many stations.展开更多
During his state visit to Kazakhstan this September,President Xi Jinping made a concrete proposal to build a Silk Road Economic Belt(SREB for short in the following paragraphs)from the aspects of policy communication,...During his state visit to Kazakhstan this September,President Xi Jinping made a concrete proposal to build a Silk Road Economic Belt(SREB for short in the following paragraphs)from the aspects of policy communication,road connectivity,展开更多
Based on the annual sample data on food production in China since the reform and opening up,we select 8 main factors influencing the total food production( growing area,application rate of chemical fertilizer,effectiv...Based on the annual sample data on food production in China since the reform and opening up,we select 8 main factors influencing the total food production( growing area,application rate of chemical fertilizer,effective irrigation area,the affected area,total machinery power,food production cost index,food production price index,financial funds for supporting agriculture,farmers and countryside),and put them into categories of material input,resources and environment,and policy factors. Using the factor analysis,we carry out the multi-angle analysis of these typical influencing factors one by one through the time series trend chart. It is found that application rate of chemical fertilizer,the growing area of food crops and drought-affected area become the key factors affecting food production. On this basis,we set forth the corresponding recommendations for improving the comprehensive food production capacity.展开更多
Seismic data show some important characteristics, such as big volume and strong timeliness. Specific to the time series data of earthquake precursory observations, a piecewise linear representation based on the slidin...Seismic data show some important characteristics, such as big volume and strong timeliness. Specific to the time series data of earthquake precursory observations, a piecewise linear representation based on the sliding window mean value （PLR_MTSW） algorithm is proposed. With this algorithm, the mutation points can be identified accurately according to the rate Of mean value change, while the main features of time series are maintained well. This algorithm can also smooth the noise and improve the compression accuracy with sliding window. Meanwhile the local extreme points can be identified effectively according to the change of mean value trend within window.展开更多
The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seve...The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seventy five college students from 37 universities sent by China International Youth Exchange Center,Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea and Japan Society attended the Forum.Lee Boksil,Vice-Minister of Ministry of展开更多
The main purpose of this study is to assess the climate variability and change through statistical processing tools that able to highlight annual and monthly rainfall behavior between 1970 and 2010 in six strategical ...The main purpose of this study is to assess the climate variability and change through statistical processing tools that able to highlight annual and monthly rainfall behavior between 1970 and 2010 in six strategical raingauges located in northern (Saint-Louis, Bakel), central (Dakar, Kaolack), and southern (Ziguinchor, Tambacounda) part of Senegal. Further, differences in sensitivity of statistical tests are also exhibited by applying several tests rather than a single one to check for one behavior. Dependency of results from statistical tests on studied sequence in time series is also shown comparing results of tests applied on two different periods (1970-2010 and 1960-2010). Therefore, between 1970 and 2010, exploratory data analysis is made to give in a visible manner a first idea on rainfall behavior. Then, Statistical characteristics such as the mean, variance, standard deviation, coefficient of variation, skewness and kurtosis are calculated. Subsequently, statistical tests are applied to all retained time series. Kendall and Spearman rank correlation tests allow verifying whether or not annual rainfall observations are independent. Hubert’s procedures of segmentation, Pettitt, Lee Heghinian and Buishand tests allow checking rainfall homogeneity. Trend is undertaken by first employing the annual and seasonal Mann-Kendall trend test, and in case of significance, magnitude of trend is calculated by Sen’s slope estimator tests. All statistical tests are applied in the period of 1960-2010. Explanatory analysis data indicates upwards trends for records in northern and central and trend free for southern records. Application of multiple tests shows that the Kendall and spearman ranks correlation tests lead to same conclusion. The difference in tests sensitivity was shown by outcomes of homogeneity tests giving different results either in dates of the shift occurrence or in the significance of an eventual shift. A synthesis analysis of results of tests was carried out to conclude about rainfall behaviors. Tests for homogeneity show that southern rainfall is homogeneous, while northern and central ones are not. According to trend test, upwards trends in Northern and central rainfall trend free in southern assumption in exploratory data analysis have been confirmed. The Sen’s slop estimator shows that all retained trend can be assumed to linear type. The same test over the period 1960-2010 shows independence of observations in all raingauges and exhibits neither trends nor breaks. This seems to show a return to a wet period.展开更多
The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta re...The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta region of Nigeria. Using daily or 24-hourly annual maximum series (AMS) data with the Indian Meteorological Department (IMD) and the modified Chowdury Indian Meteorological Department (MCIMD) models were adopted to downscale the time series data. Mann-Kendall (MK) trend and Sen’s Slope Estimator (SSE) test showed a statistically significant trend for Uyo and Benin, while Port Harcourt and Warri showed mild trends. The Sen’s Slope magnitude and variation rate were 21.6, 10.8, 6.00 and 4.4 mm/decade, respectively. The trend change-point analysis showed the initial rainfall change-point dates as 2002, 2005, 1988, and 2000 for Uyo, Benin, Port Harcourt, and Warri, respectively. These prove positive changing climatic conditions for rainfall in the study area. Erosion and flood control facilities analysis and design in the Niger Delta will require the application of Non-stationary IDF modelling.展开更多
Objective To describe survival trends and global patterns of esophageal cancer(EC)using survival data from population-based cancer registries.Methods We systematically searched PubMed,EMBASE,Web of Science,SEER,and Si...Objective To describe survival trends and global patterns of esophageal cancer(EC)using survival data from population-based cancer registries.Methods We systematically searched PubMed,EMBASE,Web of Science,SEER,and SinoMed databases for articles published up to 31 December 2023.Eligible EC survival estimates were evaluated according to country or region,period,sex,age group,pathology,and disease stage.Results After 2010,Jordan exhibited the highest age-standardized 5-year relative survival rates(RSRs)/net survival rates(NSRs)at 41.1%between 2010 and 2014,while India had the lowest,at 4.1%.Survival rates generally improved with diagnostic age across most countries,with significant increases in South Korea and China,of 12.7%and 10.5%between 2000 and 2017,respectively.Survival was higher among women compared to men,ranging from 0.4%-10.9%.Survival rates for adenocarcinoma and squamous cell carcinoma were similar,differing by about 4%.In China,the highest age-standardized RSRs/NSRs was 33.4%between 2015 and 2017.Meanwhile,the lowest was 5.3%,in Qidong(Jiangsu province)between 1992-1996.Conclusion Global EC survival rates have improved significantly in recent decades,but substantial geographical,sex,and age disparities still exist.In Asia,squamous cell carcinoma demonstrated superior survival rates compared to adenocarcinoma,while the opposite trend was observed in Western countries.Future research should clarify the prognostic factors influencing EC survival and tailor prevention and screening strategies to the changing EC survival patterns.展开更多
基金Supported by China Scholarship Council(CSC,No.202006945002)Chunhui Project of China Education Ministry(No.HZKY20220587)+1 种基金Tianjin Health Technology Research Project(No.TJWJ2022MS014)Tianjin Municipal Education Commission Scientific Research Program(Mental Health Education,No.2022ZDGX20).
文摘AIM:To investigate time trends in myopia and high myopia prevalence over 6y among young university adults in China.METHODS:This is a 6-year series cross-sectional study from 2016 to 2021.Totally 4910 freshmen were enrolled and completed a questionnaire concerning age,gender,and disease history.Students with eye diseases were excluded after a detailed eye examination.The refractive status was measured by non-cycloplegic objective refraction and ocular parameters were measured by Lenstar 900.The examination followed the same protocol each year.Trends over time in myopia and high myopia prevalence,as well as ocular biometry parameters,were analyzed.RESULTS:From 2016 to 2021,the axial length(AL)and corneal radius(CR)increased significantly(P=0.002 for AL;P=0.04 for CR).However,the spherical equivalent(SE)and the ratio of axial length to the corneal radius(AL/CR)did not change significantly(P=0.59 for SE;P=0.24 for AL/CR).The frequency of AL≥26.0 mm increased from 26.6%in 2016 to 29.3%in 2021(P=0.05 for trend).The prevalence of myopia and high myopia did not change significantly in our study(P≥0.18).Compared to a similar cross-sectional study conducted 10 years ago,the prevalence of myopia decreased significantly(94.9%vs 91.8%,P<0.001).Whereas the prevalence of high myopia increased largely(18.12%vs 27.6%,P<0.001).CONCLUSION:The prevalence of high myopia increases in young university adults during 10y period.Myopia control should begin earlier in childhood.However,these interventions are still needed for high myopia even in young adulthood.
基金supported by grants from Fundacao de Amparo à Pesquisa do Estado do Rio de Janeiro-FAPERJ [E-26/2014-202.008]Conselho Nacional de Desenvolvimento Científico e Tecnológico–CNPq [302401/2016-4]
文摘Background: Currently, surgical resection represents the only curative treatment for pancreatic cancer(PC), however, the majority of tumors are no longer resectable by the time of diagnosis. The aim of this study was to describe time trends and distribution of pancreaticoduodenectomies(PDs) performed for treating PC in Brazil in recent years. Methods: Data were retrospectively obtained from Brazilian Health Public System(namely DATASUS) regarding hospitalizations for PC and PD in Brazil from January 2008 to December 2015. PC and PD rates and their mortalities were estimated from DATASUS hospitalizations and analyzed for age, gender and demographic characteristics. Results: A total of 2364 PDs were retrieved. Albeit PC incidence more than doubled, the number of PDs increased only 37%. Most PDs were performed in men(52.2%) and patients between 50 and 69 years old(59.5%). Patients not surgically treated and those 70 years or older had the highest in-hospital mortality rates. The most developed regions(Southeast and South) as well as large metropolitan integrated municipalities registered 76.2% and 54.8% of the procedures, respectively. LMIM PD mortality fluctuated, ranging from 13.6% in 2008 to 11.8% in 2015. Conclusions: This study suggests a trend towards regionalization and volume-outcome relationships for PD due to PC, as large metropolitan integrated municipalities registered most of the PDs and more stable mortality rates. The substantial differences between PD and PC increasing rates reveals a limiting step on the health system resoluteness. Reduction in the number of hospital beds and late access to hospitalization, despite improvement in diagnostic methods, could at least in part explain these findings.
基金financial support of the China Scholarship Council(201913043)Hainan University,Agricultural Science and Research Excellence Talents of Ministry of Agriculture and Rural Affairs,China(202105510311095).
文摘Adequate dietary zinc intake remains a public health challenge in China.Also,there is a lack of information on the relationship between Zn intake and food consumption patterns across provinces and over time.In this study,data from the China Health and Nutrition Survey 2004-2011(21,266 individuals)was used to explore associations between dietary Zn intake and sociodemographic factors.Zn intake per person declined from 11.1 mg·d^(-1)in 2004 to 9.89 mg·d^(-1)in 2011,with reduction in cereal consumption the greatest contributor to this.However,the reduction resulting from the lower cereal consumption was only partly compensated by an increase in consumption of Zn-rich foods.The percentage of the study population with inadequate Zn intake increased from 23% in 2004 to 37% in 2011.While Zn intake was positively associated with income levels in each survey year,the time trend for all income levels was a gradually reducing Zn intake.In all years,males had an average higher dietary Zn intake,whereas no significant difference was found between living areas.In conclusion,this study shows that dietary Zn inadequacy was high and has increased over the studied period.Remediation could be sought by shifting dietary patterns toward more Zn-dense food or by enhancing Zn concentration through biofortification.
文摘BACKGROUND Relative changes in the prevalence of gastrointestinal(GI)diseases have been reported worldwide over the past decades.However,data on changing trends of upper GI diseases remain scarce in sub-Saharan Africa.This study examines the shifting patterns of upper GI endoscopic findings over 35 years in Ethiopia.AIM To analyze trends in upper GI endoscopic findings over two distinct time periods,35 years apart,in Ethiopia.METHODS We extracted findings from 8412 upper GI endoscopies performed between 2016 and 2024 at a tertiary referral center in Addis Ababa,Ethiopia.Patient characteristics,indications,and endoscopic findings were analyzed using descriptive statistics and presented in tables,map and graphs.These findings were compared to 10000 procedures conducted between 1979 and 1994.Key endoscopic findings were identified,and percentage changes in disease prevalence were calculated.RESULTS Between the two study periods,the male-to-female ratio of patients undergoing upper GI endoscopy shifted from 2:1 to 1.4:1,while the median patient age increased from 36 to 40 years.The proportion of patients older than 50 years doubled(14.6%to 30.2%),and referrals from outside Addis Ababa increased from 33%to 57%.The prevalence of peptic ulcer disease and its complications decreased from 46.2%to 9.5%.Conversely,gastroesophageal varices increased from 9.5%to 21.8%,and upper GI malignancies rose from 3.6%to 18.8%.CONCLUSION This study sheds light on critical epidemiological shifts in upper GI diseases in Ethiopia,with a decline in peptic ulcer disease and a rise in portal hypertensive lesions and malignancies which have important public health implications.These findings underscore the need for increased awareness,improved clinical practices,enhanced resource allocation,and expanded access to early diagnosis and treatment of prevailing conditions.Preventive strategies targeting immunization and treatment of viral hepatitis,schistosomiasis,and Helicobacter pylori infection are urgently needed.
文摘Background:The epidemiological investigation of Hodgkin’s lymphoma(HL)among the genetically peculiar population of the Italian island of Sardinia might provide interesting etiological clues.Methods:We used the database of 1974-2003 incident cases of hematological malignancies in Sardinia and Bayesian methods to explore the time trend and geographic spread of HL incidence by sex,and age whether≤44 or≥45 years.We also tested its association with several socio-economic and environmental risk factors.Results:The age-and sex-standardized(world population)incidence rate of HL was 2.6 per 100,000(95%CI,2.5-2.8).Over the study period,HL incidence increased linearly in both sexes and among those aged≤44 years but not above that age.Cases clustered among young women in a central-western area covering four bordering administrative units(13 cases vs.5.7 expected,P=0.002).The posterior probability of excess HL cases aged≤44 years was elevated only in a commune in the suburban area of the region’s capital.Cases aged≥45 years were uniformly spread over the region.Among the risk factors we explored,urban residence was associated with an elevated and goat farming with a decreased risk of HL occurrence.We did not observe a link with socio-economic deprivation,environmental exposures,or multiple sclerosis.The geographic spread of COVID-19 was also unrelated to past HL incidence.Conclusions:Our results prompt further in-depth investigation into the previously undetected cluster and the nature of the observed associations.
文摘The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyses (Fourier series analysis, t-test, and Mann-Kendall test). The stations were spatially divided into three regions: northwest (NW), southwest (SW), and southeast (SE) to evaluate spatial variability in temperature. The results of the study reveal that the annual maximum mean temperature showed increasing trend for NW, and mixed trends for SW and SE regions. The variability was found to be more for northern stations as compared to southern stations for annual extreme minimum temperature. In addition, the trend slope per 100 years for the average annual extreme minimum temperature increased within the range of -0.8°C (Stratford) to 15°C (Porcupine). The seasonal analysis demonstrated that extreme maximum temperature has an increasing trend and maximum mean temperature has a decreasing trend during summer and winter. The extreme minimum temperature for winter illustrated an increasing trend (90%) with 22% statistically significant for NW region. For the SW region, the trend is also increasing (80%) for most of the temperature variables and 25% of temperature data were significantly increased in the SW region. The SE region stations showed overall very clear increasing trends (95%) for all the temperature variables. The data also showed that 47% of data were statistically significant in the SE region. The analysis of variance accounted for by trend, significant periodicities, and random component show that the pattern is similar for the percent of variance accounted for periodicities, and random component contribute dominantly for the four temperature variables and frost free days (FFD) for all three regions. Overall, the study reveals that the extreme minimum temperature is increasing annually and seasonally, with statistically significant at many stations.
文摘During his state visit to Kazakhstan this September,President Xi Jinping made a concrete proposal to build a Silk Road Economic Belt(SREB for short in the following paragraphs)from the aspects of policy communication,road connectivity,
基金Supported by Humanities and Social Sciences Fund of the Ministry of Education(12YJC790094)Tianjin Philosophy and Social Science Planning Project(TJYY13-028TJLJ13-011)
文摘Based on the annual sample data on food production in China since the reform and opening up,we select 8 main factors influencing the total food production( growing area,application rate of chemical fertilizer,effective irrigation area,the affected area,total machinery power,food production cost index,food production price index,financial funds for supporting agriculture,farmers and countryside),and put them into categories of material input,resources and environment,and policy factors. Using the factor analysis,we carry out the multi-angle analysis of these typical influencing factors one by one through the time series trend chart. It is found that application rate of chemical fertilizer,the growing area of food crops and drought-affected area become the key factors affecting food production. On this basis,we set forth the corresponding recommendations for improving the comprehensive food production capacity.
基金Project supported by the Shanghai Leading Academic Discipline Project(Grant No.J50103)the Natural Science Foundation of Shanghai Municipality(Grant No.08ZR1408400)
文摘Seismic data show some important characteristics, such as big volume and strong timeliness. Specific to the time series data of earthquake precursory observations, a piecewise linear representation based on the sliding window mean value （PLR_MTSW） algorithm is proposed. With this algorithm, the mutation points can be identified accurately according to the rate Of mean value change, while the main features of time series are maintained well. This algorithm can also smooth the noise and improve the compression accuracy with sliding window. Meanwhile the local extreme points can be identified effectively according to the change of mean value trend within window.
文摘The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seventy five college students from 37 universities sent by China International Youth Exchange Center,Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea and Japan Society attended the Forum.Lee Boksil,Vice-Minister of Ministry of
文摘The main purpose of this study is to assess the climate variability and change through statistical processing tools that able to highlight annual and monthly rainfall behavior between 1970 and 2010 in six strategical raingauges located in northern (Saint-Louis, Bakel), central (Dakar, Kaolack), and southern (Ziguinchor, Tambacounda) part of Senegal. Further, differences in sensitivity of statistical tests are also exhibited by applying several tests rather than a single one to check for one behavior. Dependency of results from statistical tests on studied sequence in time series is also shown comparing results of tests applied on two different periods (1970-2010 and 1960-2010). Therefore, between 1970 and 2010, exploratory data analysis is made to give in a visible manner a first idea on rainfall behavior. Then, Statistical characteristics such as the mean, variance, standard deviation, coefficient of variation, skewness and kurtosis are calculated. Subsequently, statistical tests are applied to all retained time series. Kendall and Spearman rank correlation tests allow verifying whether or not annual rainfall observations are independent. Hubert’s procedures of segmentation, Pettitt, Lee Heghinian and Buishand tests allow checking rainfall homogeneity. Trend is undertaken by first employing the annual and seasonal Mann-Kendall trend test, and in case of significance, magnitude of trend is calculated by Sen’s slope estimator tests. All statistical tests are applied in the period of 1960-2010. Explanatory analysis data indicates upwards trends for records in northern and central and trend free for southern records. Application of multiple tests shows that the Kendall and spearman ranks correlation tests lead to same conclusion. The difference in tests sensitivity was shown by outcomes of homogeneity tests giving different results either in dates of the shift occurrence or in the significance of an eventual shift. A synthesis analysis of results of tests was carried out to conclude about rainfall behaviors. Tests for homogeneity show that southern rainfall is homogeneous, while northern and central ones are not. According to trend test, upwards trends in Northern and central rainfall trend free in southern assumption in exploratory data analysis have been confirmed. The Sen’s slop estimator shows that all retained trend can be assumed to linear type. The same test over the period 1960-2010 shows independence of observations in all raingauges and exhibits neither trends nor breaks. This seems to show a return to a wet period.
文摘The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta region of Nigeria. Using daily or 24-hourly annual maximum series (AMS) data with the Indian Meteorological Department (IMD) and the modified Chowdury Indian Meteorological Department (MCIMD) models were adopted to downscale the time series data. Mann-Kendall (MK) trend and Sen’s Slope Estimator (SSE) test showed a statistically significant trend for Uyo and Benin, while Port Harcourt and Warri showed mild trends. The Sen’s Slope magnitude and variation rate were 21.6, 10.8, 6.00 and 4.4 mm/decade, respectively. The trend change-point analysis showed the initial rainfall change-point dates as 2002, 2005, 1988, and 2000 for Uyo, Benin, Port Harcourt, and Warri, respectively. These prove positive changing climatic conditions for rainfall in the study area. Erosion and flood control facilities analysis and design in the Niger Delta will require the application of Non-stationary IDF modelling.
基金supported by the National Key Project of Research and Development Program of China[2021YFC2500404,2021YFC2500405].
文摘Objective To describe survival trends and global patterns of esophageal cancer(EC)using survival data from population-based cancer registries.Methods We systematically searched PubMed,EMBASE,Web of Science,SEER,and SinoMed databases for articles published up to 31 December 2023.Eligible EC survival estimates were evaluated according to country or region,period,sex,age group,pathology,and disease stage.Results After 2010,Jordan exhibited the highest age-standardized 5-year relative survival rates(RSRs)/net survival rates(NSRs)at 41.1%between 2010 and 2014,while India had the lowest,at 4.1%.Survival rates generally improved with diagnostic age across most countries,with significant increases in South Korea and China,of 12.7%and 10.5%between 2000 and 2017,respectively.Survival was higher among women compared to men,ranging from 0.4%-10.9%.Survival rates for adenocarcinoma and squamous cell carcinoma were similar,differing by about 4%.In China,the highest age-standardized RSRs/NSRs was 33.4%between 2015 and 2017.Meanwhile,the lowest was 5.3%,in Qidong(Jiangsu province)between 1992-1996.Conclusion Global EC survival rates have improved significantly in recent decades,but substantial geographical,sex,and age disparities still exist.In Asia,squamous cell carcinoma demonstrated superior survival rates compared to adenocarcinoma,while the opposite trend was observed in Western countries.Future research should clarify the prognostic factors influencing EC survival and tailor prevention and screening strategies to the changing EC survival patterns.
