This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrat...This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality.展开更多
Based on comprehensive analysis of the impact of population aging to social and economic development,a comprehensive evaluation system including 18 indexes was constructed for evaluating regional pressure of populatio...Based on comprehensive analysis of the impact of population aging to social and economic development,a comprehensive evaluation system including 18 indexes was constructed for evaluating regional pressure of population aging on social and economic development.Using statistics data of 31 regions in China from 2004 to 2008,the pressure of population aging on social and economic development,was comprehensively evaluated by using the factor analysis method.The spatial distribution of population aging in China was also analyzed.This study is to provide scientific basis for government to make strategies of coping with population aging according to regional pressure of population aging on social and economic development in China.展开更多
Objective:To understand the dietary intake of high-risk population with hypertension in Haikou,and to analyze the relationship between dietary intake and blood pressure,especially the relationship between sodium intak...Objective:To understand the dietary intake of high-risk population with hypertension in Haikou,and to analyze the relationship between dietary intake and blood pressure,especially the relationship between sodium intake and blood pressure,so as to provide a scientific basis for salt reduction.Methods:A multi-stage cluster sampling 2021 was used from July to December to collect 3-4 cscs from each of the four districts in Haikou.A total of 15 cscs were collected,295 permanent residents aged 55-74 were recruited from 15 community service centers,with 20 eligible subjects from each community.The subjects underwent general physical examination,laboratory tests,and a dietary survey using the self-developed Android phone APP“Nutrition Assistant”(registration number:2021SR1547832).SPSS 21.0 was used 2 for t test,x^(2) test and multiple Regression analysis.Result:In Haikou,69.4%of the subjects had energy intake above energy requirement,and 44.8%had fat intake above the acceptable range of macronutrients.There were only differences in energy,carbohydrate,vitamin B 6 and sodium intake(t=-2.174,-1.990,2.333,-5.442,P=0.031,0.048,0.021,<0.001,respectively).There were significant differences in BMI,family history of chronic diseases,systolic blood 2 pressure and diastolic blood pressure(f value or x^(2) value were 4.260,19.045,139.916,36.864,P value were 0.015,<0.001,<0.001,<0.001,respectively).Multiple Regression analysis analysis showed that 24h sodium excretion was significantly correlated with systolic and diastolic blood pressure(t=12.964,P<0.001),systolic and diastolic blood pressure increased by 0.135 mmhg and 0.068 mmhg,respectively.Conclusion:The dietary intake of the middle-aged and elderly people at high risk of hypertension in the Haikou community was unbalanced,and the intake of sodium salt was strongly correlated with blood pressure,it is necessary to continue to promote salt reduction as one of the key ways to prevent and control hypertension.展开更多
Antarctic krill (Euphausia superba Dana) was collected using a High Speed Collector and an Isaac-Kidd midwater trawl (IKMT) net during the austral summer of 2007/2008 and 2008/2009 in the circumpolar and Prydz Bay...Antarctic krill (Euphausia superba Dana) was collected using a High Speed Collector and an Isaac-Kidd midwater trawl (IKMT) net during the austral summer of 2007/2008 and 2008/2009 in the circumpolar and Prydz Bay regions of the Southern Ocean, respectively. Combined with the simultaneous recording of environmental factors, spatial distribution, population structure and growth condition of E. superba were studied. The abundance of E. superba in the Weddell Sea was higher than in Prydz Bay. However, the abundance of E. superba in both the Weddell Sea and Prydz Bay was lower than figures reported in previous krill surveys for the same time period. With respect to the total study area, E. superba displayed a normal growing state during the two expeditions. E. superba grew relatively poorly in some stations, which may be due to the late retreat of sea ice or lower chlorophyll a concentrations. The number of juvenile E. superba collected using the High Speed Collector was proportionally greater in stations located at the edge of the sea ice, while adults dominated in long-term non-ice regions. This phenomenon reflects the different distribution pattern between juvenile and adult krill. The population structure of E. superba differed between sea regions, which may affect recruitment.展开更多
Background The relationships between dietary intake of soybean products and incident hypertension were still uncertain.This study aimed to illustrate the associations between intake of soybean products with risks of i...Background The relationships between dietary intake of soybean products and incident hypertension were still uncertain.This study aimed to illustrate the associations between intake of soybean products with risks of incident hypertension and longitudinal changes of blood pressure in a prospective cohort study.Methods We included 67,499 general Chinese adults from the Project of Prediction for Atherosclerosis Cardiovascular Disease Risk in China(China-PAR).Information about soybean products consumption was collected by standardized questionnaires,and study participants were categorized into the ideal(≥125 g/day)or non-ideal(<125 g/day)group.Hazard ratios(HRs)and corresponding 95%confidence intervals(95%CIs)for incident hypertension were calculated using Cox proportional hazard models.Among participants with repeated measures of blood pressure,generalized linear models were used to examine the relationships between soybean products consumption and blood pressure changes.Results During a median follow-up of 7.4 years,compared with participants who consumed<125 g of soybean products per day,multivariable adjusted HR for those in the ideal group was 0.73(0.67-0.80).This inverse association remained robust across most subgroups while significant interactions were tested between soybean products intake and age,sex,urbanization and geographic region(P values for interaction<0.05).The mean systolic and diastolic blood pressure levels were 1.05(0.71-1.39)mmHg and 0.44(0.22-0.66)mmHg lower among participants in the ideal group than those in the non-ideal group.Conclusions Our study showed that intake of soybean products might reduce the long-term blood pressure levels and hypertension incidence among Chinese population,which has important public health implications for primary prevention of hypertension.展开更多
Background: Canopy structure, defined by leaf area index (LAI), fractional vegetation cover (FCover) and fraction of absorbed photosynthetically active radiation (fAPAR), regulates a wide range of forest functi...Background: Canopy structure, defined by leaf area index (LAI), fractional vegetation cover (FCover) and fraction of absorbed photosynthetically active radiation (fAPAR), regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics. Methods: Here, we introduce the Global LAI database: a global dataset of field-based canopy structure measurements spanning tropical forests in four continents (Africa, Asia, Australia and the Americas). We use these measurements to test for climate dependencies within and across continents, and to test for the potential of anthropogenic disturbance and forest protection to modulate those dependences. Results: Using data collected from 887 tropical forest plots, we show that maximum water deficit, defined across the most arid months of the year, is an important predictor of canopy structure, with all three canopy attributes declining significantly with increasing water deficit. Canopy attributes also increase with minimum temperature, and with the protection of forests according to both active (within protected areas) and passive measures (through topography). Once protection and continent effects are accounted for, other anthropogenic measures (e.g. human population) do not improve the model. Conclusions: We conclude that canopy structure in the tropics is primarily a consequence of forest adaptation to the maximum water deficits historically experienced within a given region. Climate change, and in particular changes in drought regimes may thus affect forest structure and function, but forest protection may offer some resilience against this effect.展开更多
AIM To investigate the association between hepatic steatosis and change in left ventricular mass index(LVMI) over five years, and examine whether systolic and diastolic blood pressures are mediators of the association...AIM To investigate the association between hepatic steatosis and change in left ventricular mass index(LVMI) over five years, and examine whether systolic and diastolic blood pressures are mediators of the association between hepatic steatosis and LVMI using a general population sample.METHODS We analyzed data from the Study of Health in Pomerania. The study population comprised 1298individuals aged 45 to 81 years. Hepatic steatosis was defined as the presence of a hyperechogenic pattern of the liver together with elevated serum alanine transferase levels. Left ventricular mass was determined echocardiographically and indexed to height2.7. Path analyses were conducted to differentiate direct and indirect paths from hepatic steatosis to LVMI encompassing systolic and diastolic blood pressure as potential mediating variables.RESULTS Hepatic steatosis was a significant predictor for all measured echocardiographic characteristics at baseline. Path analyses revealed that the association of hepatic steatosis with LVMI change after five years was negligibly small(β =-0.12, s.e. = 0.21, P = 0.55). Systolic blood pressure at baseline was inversely associated with LVMI change(β =-0.09, s.e. = 0.03, P < 0.01), while no association between diastolic blood pressure at baseline and LVMI change was evident(β = 0.03, s.e. = 0.05, P = 0.56). The effect of the indirect path from hepatic steatosis to LVMI via systolic baseline blood pressure was small(β =-0.20, s.e. = 0.10, P = 0.07). No indirect effect was observed for the path via diastolic baseline blood pressure(β = 0.03, s.e. = 0.06, P = 0.60). Similar associations were observed in the subgroup of individuals not receiving beta-blockers, calcium channel blockers, or drugs acting on the reninangiotensin system.CONCLUSION Baseline associations between hepatic steatosis and LVMI do not extend to associations with LVMI change after five years. More studies are needed to study the longitudinal effects of hepatic steatosis on LVMI.展开更多
The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665.985 km 2 during the period 1987\|1999 in North ...The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665.985 km 2 during the period 1987\|1999 in North Shaanxi. This increase is less than the loss in arable land by urbanization. The accelerated rate of change in agricultural areas calls for more rapid surveys of urbanization and loss of arable land. Remote sensing has a number of advantages over ground\|based methods for such surveys. The multi\|scale concept of remote sensing data help us study the problem in four towns. Several maps were produced to analyze the situation of urban coverage in different times. The evaluation of the status, rate and risk of urbanization are based on an accepted average of urban increase as 2% of population growth per year.展开更多
Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods use...Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(4) In addition, compared with traditional results, the revised result indicated that the population pressure was larger. Based on these results, the following conclusions were made:(1) the revised method for estimating population density that incorporates the RDLS is reasonable and practical,(2) the potential population pressure in the southeastern mountainous areas is substantial,(3) the characteristics of the terrain in the high mountainous areas are important for the scattered distribution of the population, and(4) the population distribution of mountainous areas in China should be guided by local conditions, such as social, economic, and topographic conditions.展开更多
Along with China's urbanization,the spatial redistribution of the country's population has led to difficulties for local governance,especially in areas experiencing population outflows.Municipal amalgamation i...Along with China's urbanization,the spatial redistribution of the country's population has led to difficulties for local governance,especially in areas experiencing population outflows.Municipal amalgamation is an ffctive response.This study uses administrative system code data that are accurate at the community and village level to verify the causal relationship between migration and village or community municipal amalgamation.It shows that migration has been an important reason for municipal amalgamation.Counties with greater population outflow have experienced more frequent amalgamation,manifesting a decrease in the numbers of villages and communities.This study,also examined the consequences of this amalgamation,finding that it can significantly alleviate local governments'fiscal pressures and promote public services in the long term.It is of great importance for improving the grassroots governance of population outflow areas during rapid urbanization in China.展开更多
A multiphase computational fluid dynamics(CFD)model coupled with the population balance equation(PBE)was developed in a homogeneous air-kerosene bubble column under elevated pressure(P).The specific pressure drop(ΔP/...A multiphase computational fluid dynamics(CFD)model coupled with the population balance equation(PBE)was developed in a homogeneous air-kerosene bubble column under elevated pressure(P).The specific pressure drop(ΔP/L),gas holdup(α_(G)),and Sauter mean diameter(d_(32))were experimentally measured in the bubble column with 1.8 m height and 0.1 m inner diameter,which was operated at a superficial gas velocity of 12.3 mm·s^(-1),and P=1-35 bar(1 bar=10^(5) Pa).A modified drag coefficient model was proposed to consider the effect of bubble swarm and pressure on hydrodynamics of the bubble column.The Luo breakage model was modified to account for liquid density,viscosity,surface tension and gas density.TheΔP/L,α_(G),and d_(32) obtained from the CFD model were compared with experimental data,and the gas density-dependent parameters of the CFD model were identified.With increasing P from 1 to 35 bar,theα_(G) varied from 5.4%to 7.2% and the d32 decreased from 2.3 to 1.5 mm.The CFD-PBE model is applicable to predict hydrodynamics of pressurized bubble columns for gas-organic liquid in the homogeneous regime.展开更多
Competition is a common phenomenon in agriculture production.Research on the relationship between competitive ability and crop yield is extensive,but the results have been inconsistent.Few studies have focused on the ...Competition is a common phenomenon in agriculture production.Research on the relationship between competitive ability and crop yield is extensive,but the results have been inconsistent.Few studies have focused on the relationship between population competitive intensity and yield of maize(Zea mays L.)cultivars.The main objective of this study was to determine if a consistent relationship exists between maize yield and competitive ability.A two-year field experiment was conducted,employing a de Wit replacement series design.When two maize cultivars were grown in a mixture,yield was reduced for the modern cultivar and increased for the older cultivar.In each replacement series,per plant level yield of each cultivar,and population level yield of the mixture,decreased with increasing proportion of the older cultivar.Competitive ratio(CR)reflected differences in competitive ability of the three maize cultivars.In each replacement series,population competition pressure(PCP)increased with increasing proportion of the older cultivar,indicating that the older cultivar was a strong competitor.Biomass yield,grain yield,harvest index,thousand-kernel weight,and kernel number per plant,were negatively correlated with PCP.Our results demonstrated that inter-cultivar competition affects maize productivity,and increasing PCP will decrease translocation of assimilates to grain and,ultimately,reduce yield.Therefore,there is a negative correlation between population competitive intensity and yield performance in maize,breeders should develop a communal ideotype that would not perform well in competition in future.展开更多
The growing stock assessment of three different teak forest stands (Tuirial: 500 m asl, Sairang: 200 m asl and Phunchawng: 550 m asl) was done in 2006 in Mizoram, India. Five diameter classes were arbitrarily est...The growing stock assessment of three different teak forest stands (Tuirial: 500 m asl, Sairang: 200 m asl and Phunchawng: 550 m asl) was done in 2006 in Mizoram, India. Five diameter classes were arbitrarily established for knowing the volume attribute data and population structure, viz. a (10-20 cm), b (20-30 cm), c (30-40 cm), d (40-50 cm), and e (50-60 cm). Results revealed that the density of the individuals among the studied stands varied from 280 stems/ha to 620 stems/ha. The average diameter of all the individuals ranged between 27.48 cm and 35.43 cm. Similarly, the average height was oscillated between 17.87 m and 22.24 m. The total basal area was recorded between 24.28 m2.ha-1 and 45.80 m2.ha"l. The maximum and minimum values of total growing stock under all the diameter classes were 669.01 m3.ha-1 and 284.7 m3.ha-1, respectively. The representation of population structure of different stands explained that the perpetuation of this species was ensured for a quite long time.展开更多
Background: The objective of the present study was to compare the relationship of anthropometric and physiometric characteristics using principal component factor analysis among three groups of type 2 diabetic subject...Background: The objective of the present study was to compare the relationship of anthropometric and physiometric characteristics using principal component factor analysis among three groups of type 2 diabetic subjects such as males, pre and postmenopausal females in North Indian Punjabi population. Method: A total of 349 type 2 diabetic subjects (males 157;females 192;88 pre and 104 postmenopausal) were ascertained for the present study. Different anthropometric and physiometric measurements were taken. Principal component factor analysis (PCFA) was applied to identify the components which are more close to type 2 diabetes among the three groups. Results: PCFA revealed five uncorrelated components which explained 79% of the total variance among diabetic males and six unrelated components which explained 78% of the total variance among pre and postmenopausal females. The important two factors could be identified as central obesity (factor 1) and blood pressure (factor 2) among these three groups. Conclusion: Higher clustering of obesity and blood pressures were found in diabetic males as com pared to pre and postmenopausal diabetic females in North Indian Punjabi population whereas, waist to hip ratio (WHR) has maximum loading in postmenopausal females as compared to others.展开更多
In this paper,a nonlinear mathematical model is proposed and analyzed to study the depletion of forestry resources caused simultaneously by population and population pressure augmented industrialization.The control of...In this paper,a nonlinear mathematical model is proposed and analyzed to study the depletion of forestry resources caused simultaneously by population and population pressure augmented industrialization.The control of population pressure,using economic efforts is also considered in the modeling process.It is assumed that cumulative biomass density of forestry resources and the density of population follow logistic models.It is further assumed that the density of population and the level of industrialization increase as the cumulative biomass density of forestry resources increases.The cumulative density of economic efforts,which are applied to control the population pressure,is considered to be proportional to the population pressure.The model analysis shows that as the population pressure increases,the level of industrialization increases leading to decrease in the cumulative biomass density of forestry resources.It is found that if population pressure is controlled by using some economic efforts,the decrease in cumulative biomass density of forestry resources can be made much less than the case when no control is applied.It is also noted that if the population pressure augmented industrialization increases without control,the forestry resources may become extinct.展开更多
Sub-Saharan Africa is currently undergoing an epidemiological transition from a disease burden largely attributable to communicable diseases to that resulting from a combination of both communicable and chronic non-co...Sub-Saharan Africa is currently undergoing an epidemiological transition from a disease burden largely attributable to communicable diseases to that resulting from a combination of both communicable and chronic non-communicable diseases.Data on chronic disease incidence,lifestyle,environmental and genetic risk factors are sparse in this region.This report aimed at providing relevant information in respect to risk factors that increase blood pressure and lead to development of intermediate cardiovascular phenotypes.We presented the rationale,objectives and key methodological features of the Nigerian Population Research on Environment,Gene and Health(NIPREGH) study.The challenges encountered in carrying out population study in this part of the world and the approaches at surmounting them were also presented.The preliminary data as at 20 November 2013 showed that out of the 205 individuals invited starting from early April 2013,160(72 women) consented and were enrolled;giving a response rate of 78%.Participants' age ranged from 18 to 80 years,with a mean(SD) of 39.8(12.4) years and they were of 34 different ethnic groups spread over 24 states out of the 36 states that constitute Nigeria.The mean(SD) of office and home blood pressures were 113.0(15.2) mm Hg systolic,73.5(12.5) mm Hg diastolic and 117.3(15.0) mm Hg systolic,and 76.0(9.6) mm Hg diastolic,respectively.Forty-three(26.8%) participants were hypertensive and 8(5.0%) were diabetic.In addition to having the unique potential of recruiting a cohort that is a true representative of the entire Nigerian population,NIPREGH is feasible and the objectives realisable.展开更多
Objective To study the differences in blood pressure (BP) levels and the main factors raising BP among the population in Guangdong Province. Methods The data analyzed stem from the sampling survey of hypertension in G...Objective To study the differences in blood pressure (BP) levels and the main factors raising BP among the population in Guangdong Province. Methods The data analyzed stem from the sampling survey of hypertension in Guangdong Province in 1991, covering 42, 894 subjects over 15 years old. Individual characteristics included age, sex, occupation, education, smoking, alcohol drinking and body mass index (BMI) . Results Systolic and diastolic BP increased with age. The hypertension prevalence rate in male is higher than in female. The age - adjusted prevalence rate in office personnel is the highest (12.9 % ) among all occupations. It was increased with education level and BMI (in people educated at university and over is 13. 1 % ), and higher in smokers and alcohol-drinkers than non-smokers and non -alcohol-drinkers. Conclusions Age, occupation, education, smoking, alcohol drinking and BMI all effect BP. These risk factors should be reduced in the Guangdong population.展开更多
Although the Chinese government has published a seriesof favorable policies for textile industry,the outcome of thesefiscal policies in Chinese cotton machinery industry tends to besmall at this stage,since the effect...Although the Chinese government has published a seriesof favorable policies for textile industry,the outcome of thesefiscal policies in Chinese cotton machinery industry tends to besmall at this stage,since the effects of policies is hysteresial,and the industry had extended 2009 spring holiday amid thefinancial crisis.展开更多
基金supported by National Natural Science Foundation of China[Grant No.41171134]Peking University-Lincoln Institute Center for Urban Development and land Policy2013 Jiangsu Province Graduate Student Research Innovation project[Grant No.CXLX13_034]
文摘This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality.
基金supported by a grant from the Major Programs of Fundamental Special Work of National Science and Technology (Grand No.2007FY110300),which comes from Ministryof Science and Technology of the People’s Republic of China
文摘Based on comprehensive analysis of the impact of population aging to social and economic development,a comprehensive evaluation system including 18 indexes was constructed for evaluating regional pressure of population aging on social and economic development.Using statistics data of 31 regions in China from 2004 to 2008,the pressure of population aging on social and economic development,was comprehensively evaluated by using the factor analysis method.The spatial distribution of population aging in China was also analyzed.This study is to provide scientific basis for government to make strategies of coping with population aging according to regional pressure of population aging on social and economic development in China.
基金National Natural Science Foundation of China(No.81860577)Graduate Innovation and Entrepreneurship Project(No.HYYS2020-02)。
文摘Objective:To understand the dietary intake of high-risk population with hypertension in Haikou,and to analyze the relationship between dietary intake and blood pressure,especially the relationship between sodium intake and blood pressure,so as to provide a scientific basis for salt reduction.Methods:A multi-stage cluster sampling 2021 was used from July to December to collect 3-4 cscs from each of the four districts in Haikou.A total of 15 cscs were collected,295 permanent residents aged 55-74 were recruited from 15 community service centers,with 20 eligible subjects from each community.The subjects underwent general physical examination,laboratory tests,and a dietary survey using the self-developed Android phone APP“Nutrition Assistant”(registration number:2021SR1547832).SPSS 21.0 was used 2 for t test,x^(2) test and multiple Regression analysis.Result:In Haikou,69.4%of the subjects had energy intake above energy requirement,and 44.8%had fat intake above the acceptable range of macronutrients.There were only differences in energy,carbohydrate,vitamin B 6 and sodium intake(t=-2.174,-1.990,2.333,-5.442,P=0.031,0.048,0.021,<0.001,respectively).There were significant differences in BMI,family history of chronic diseases,systolic blood 2 pressure and diastolic blood pressure(f value or x^(2) value were 4.260,19.045,139.916,36.864,P value were 0.015,<0.001,<0.001,<0.001,respectively).Multiple Regression analysis analysis showed that 24h sodium excretion was significantly correlated with systolic and diastolic blood pressure(t=12.964,P<0.001),systolic and diastolic blood pressure increased by 0.135 mmhg and 0.068 mmhg,respectively.Conclusion:The dietary intake of the middle-aged and elderly people at high risk of hypertension in the Haikou community was unbalanced,and the intake of sodium salt was strongly correlated with blood pressure,it is necessary to continue to promote salt reduction as one of the key ways to prevent and control hypertension.
基金supported by the Polar Research Strategy Foundation of China (Grant no. 20120308)the Chinese Polar Environment Comprehensive Investigation & Assessment Programmes (Grant nos. CHINARE2013-01-06 and CHINARE2013-01-05)
文摘Antarctic krill (Euphausia superba Dana) was collected using a High Speed Collector and an Isaac-Kidd midwater trawl (IKMT) net during the austral summer of 2007/2008 and 2008/2009 in the circumpolar and Prydz Bay regions of the Southern Ocean, respectively. Combined with the simultaneous recording of environmental factors, spatial distribution, population structure and growth condition of E. superba were studied. The abundance of E. superba in the Weddell Sea was higher than in Prydz Bay. However, the abundance of E. superba in both the Weddell Sea and Prydz Bay was lower than figures reported in previous krill surveys for the same time period. With respect to the total study area, E. superba displayed a normal growing state during the two expeditions. E. superba grew relatively poorly in some stations, which may be due to the late retreat of sea ice or lower chlorophyll a concentrations. The number of juvenile E. superba collected using the High Speed Collector was proportionally greater in stations located at the edge of the sea ice, while adults dominated in long-term non-ice regions. This phenomenon reflects the different distribution pattern between juvenile and adult krill. The population structure of E. superba differed between sea regions, which may affect recruitment.
基金Supported by the Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2017-I2M-1-004,2019-I2M-2-003)National Key Research&Development Program of China(2017YFC0211700)National Natural Science Foundation of China(91843302).The authors declared no conflicts of interest.
文摘Background The relationships between dietary intake of soybean products and incident hypertension were still uncertain.This study aimed to illustrate the associations between intake of soybean products with risks of incident hypertension and longitudinal changes of blood pressure in a prospective cohort study.Methods We included 67,499 general Chinese adults from the Project of Prediction for Atherosclerosis Cardiovascular Disease Risk in China(China-PAR).Information about soybean products consumption was collected by standardized questionnaires,and study participants were categorized into the ideal(≥125 g/day)or non-ideal(<125 g/day)group.Hazard ratios(HRs)and corresponding 95%confidence intervals(95%CIs)for incident hypertension were calculated using Cox proportional hazard models.Among participants with repeated measures of blood pressure,generalized linear models were used to examine the relationships between soybean products consumption and blood pressure changes.Results During a median follow-up of 7.4 years,compared with participants who consumed<125 g of soybean products per day,multivariable adjusted HR for those in the ideal group was 0.73(0.67-0.80).This inverse association remained robust across most subgroups while significant interactions were tested between soybean products intake and age,sex,urbanization and geographic region(P values for interaction<0.05).The mean systolic and diastolic blood pressure levels were 1.05(0.71-1.39)mmHg and 0.44(0.22-0.66)mmHg lower among participants in the ideal group than those in the non-ideal group.Conclusions Our study showed that intake of soybean products might reduce the long-term blood pressure levels and hypertension incidence among Chinese population,which has important public health implications for primary prevention of hypertension.
基金supported by the‘Uncovering the variable roles of fire in savannah ecosystems’project,funded by Leverhulme Trust under grant IN-2014-022 and‘Resilience in East African Landscapes’project funded by European Commission Marie Curie Initial Training Network(FP7-PEOPLE-2013-ITN project number606879)funding from Australian Research Council,IUCN Sustain/African Wildlife Foundation and University of York Research Pump Priming Fund+1 种基金funding through the European Research Council ERC-2011-St G_20101109(project number 281986)and the British Ecological Society-Ecologists in Africa programmesupport through the‘Climate Change Impacts on Ecosystem Services and Food Security in Eastern Africa(CHIESA)’project(2011–2015),which was funded by the Ministry for Foreign Affairs of Finland,and coordinated by the International Centre of Insect Physiology and Ecology(icipe)in Nairobi,Kenya
文摘Background: Canopy structure, defined by leaf area index (LAI), fractional vegetation cover (FCover) and fraction of absorbed photosynthetically active radiation (fAPAR), regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics. Methods: Here, we introduce the Global LAI database: a global dataset of field-based canopy structure measurements spanning tropical forests in four continents (Africa, Asia, Australia and the Americas). We use these measurements to test for climate dependencies within and across continents, and to test for the potential of anthropogenic disturbance and forest protection to modulate those dependences. Results: Using data collected from 887 tropical forest plots, we show that maximum water deficit, defined across the most arid months of the year, is an important predictor of canopy structure, with all three canopy attributes declining significantly with increasing water deficit. Canopy attributes also increase with minimum temperature, and with the protection of forests according to both active (within protected areas) and passive measures (through topography). Once protection and continent effects are accounted for, other anthropogenic measures (e.g. human population) do not improve the model. Conclusions: We conclude that canopy structure in the tropics is primarily a consequence of forest adaptation to the maximum water deficits historically experienced within a given region. Climate change, and in particular changes in drought regimes may thus affect forest structure and function, but forest protection may offer some resilience against this effect.
基金Supported by Bundesministerium für Bildung und Forschung(BMBF),No.01 ZZ 0103
文摘AIM To investigate the association between hepatic steatosis and change in left ventricular mass index(LVMI) over five years, and examine whether systolic and diastolic blood pressures are mediators of the association between hepatic steatosis and LVMI using a general population sample.METHODS We analyzed data from the Study of Health in Pomerania. The study population comprised 1298individuals aged 45 to 81 years. Hepatic steatosis was defined as the presence of a hyperechogenic pattern of the liver together with elevated serum alanine transferase levels. Left ventricular mass was determined echocardiographically and indexed to height2.7. Path analyses were conducted to differentiate direct and indirect paths from hepatic steatosis to LVMI encompassing systolic and diastolic blood pressure as potential mediating variables.RESULTS Hepatic steatosis was a significant predictor for all measured echocardiographic characteristics at baseline. Path analyses revealed that the association of hepatic steatosis with LVMI change after five years was negligibly small(β =-0.12, s.e. = 0.21, P = 0.55). Systolic blood pressure at baseline was inversely associated with LVMI change(β =-0.09, s.e. = 0.03, P < 0.01), while no association between diastolic blood pressure at baseline and LVMI change was evident(β = 0.03, s.e. = 0.05, P = 0.56). The effect of the indirect path from hepatic steatosis to LVMI via systolic baseline blood pressure was small(β =-0.20, s.e. = 0.10, P = 0.07). No indirect effect was observed for the path via diastolic baseline blood pressure(β = 0.03, s.e. = 0.06, P = 0.60). Similar associations were observed in the subgroup of individuals not receiving beta-blockers, calcium channel blockers, or drugs acting on the reninangiotensin system.CONCLUSION Baseline associations between hepatic steatosis and LVMI do not extend to associations with LVMI change after five years. More studies are needed to study the longitudinal effects of hepatic steatosis on LVMI.
文摘The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increase of 665.985 km 2 during the period 1987\|1999 in North Shaanxi. This increase is less than the loss in arable land by urbanization. The accelerated rate of change in agricultural areas calls for more rapid surveys of urbanization and loss of arable land. Remote sensing has a number of advantages over ground\|based methods for such surveys. The multi\|scale concept of remote sensing data help us study the problem in four towns. Several maps were produced to analyze the situation of urban coverage in different times. The evaluation of the status, rate and risk of urbanization are based on an accepted average of urban increase as 2% of population growth per year.
基金supported by a grant from the Major State Basic Research Development Program of China (973 Program) (Grant No. 2015CB452706)National Natural Science Foundation of China (Grant No. 41471469)provided by the national scientific datasharing project Earth System Science Data Sharing Network
文摘Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(4) In addition, compared with traditional results, the revised result indicated that the population pressure was larger. Based on these results, the following conclusions were made:(1) the revised method for estimating population density that incorporates the RDLS is reasonable and practical,(2) the potential population pressure in the southeastern mountainous areas is substantial,(3) the characteristics of the terrain in the high mountainous areas are important for the scattered distribution of the population, and(4) the population distribution of mountainous areas in China should be guided by local conditions, such as social, economic, and topographic conditions.
基金the China Merchants Foundation Young Scholar Funding Program“Research on Contemporary Chinese Social Governance"project.Ning Jia appreciates the National Science Foundation(No.72073094)for research funding.Huiyong Zhong appreciates research funding from the Center for Modern Finance Research,Shanghai Jiaotong University.
文摘Along with China's urbanization,the spatial redistribution of the country's population has led to difficulties for local governance,especially in areas experiencing population outflows.Municipal amalgamation is an ffctive response.This study uses administrative system code data that are accurate at the community and village level to verify the causal relationship between migration and village or community municipal amalgamation.It shows that migration has been an important reason for municipal amalgamation.Counties with greater population outflow have experienced more frequent amalgamation,manifesting a decrease in the numbers of villages and communities.This study,also examined the consequences of this amalgamation,finding that it can significantly alleviate local governments'fiscal pressures and promote public services in the long term.It is of great importance for improving the grassroots governance of population outflow areas during rapid urbanization in China.
基金the financial support from the R&D Convergence Program of the Ministry of Science, ICT and Future Planning (MSIP)the National Research Council of Science & Technology (NST) of the Republic of Korea (CRC-14-1KRICT)supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Ministry of Science and ICT (2020R1F1A1066097)
文摘A multiphase computational fluid dynamics(CFD)model coupled with the population balance equation(PBE)was developed in a homogeneous air-kerosene bubble column under elevated pressure(P).The specific pressure drop(ΔP/L),gas holdup(α_(G)),and Sauter mean diameter(d_(32))were experimentally measured in the bubble column with 1.8 m height and 0.1 m inner diameter,which was operated at a superficial gas velocity of 12.3 mm·s^(-1),and P=1-35 bar(1 bar=10^(5) Pa).A modified drag coefficient model was proposed to consider the effect of bubble swarm and pressure on hydrodynamics of the bubble column.The Luo breakage model was modified to account for liquid density,viscosity,surface tension and gas density.TheΔP/L,α_(G),and d_(32) obtained from the CFD model were compared with experimental data,and the gas density-dependent parameters of the CFD model were identified.With increasing P from 1 to 35 bar,theα_(G) varied from 5.4%to 7.2% and the d32 decreased from 2.3 to 1.5 mm.The CFD-PBE model is applicable to predict hydrodynamics of pressurized bubble columns for gas-organic liquid in the homogeneous regime.
基金National Basic Research Program of China (973 Program, 2015CB150401)the National Maize Industry Technology Research and Development Center, Ministry of Agriculture,Chinathe Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences for their supports
文摘Competition is a common phenomenon in agriculture production.Research on the relationship between competitive ability and crop yield is extensive,but the results have been inconsistent.Few studies have focused on the relationship between population competitive intensity and yield of maize(Zea mays L.)cultivars.The main objective of this study was to determine if a consistent relationship exists between maize yield and competitive ability.A two-year field experiment was conducted,employing a de Wit replacement series design.When two maize cultivars were grown in a mixture,yield was reduced for the modern cultivar and increased for the older cultivar.In each replacement series,per plant level yield of each cultivar,and population level yield of the mixture,decreased with increasing proportion of the older cultivar.Competitive ratio(CR)reflected differences in competitive ability of the three maize cultivars.In each replacement series,population competition pressure(PCP)increased with increasing proportion of the older cultivar,indicating that the older cultivar was a strong competitor.Biomass yield,grain yield,harvest index,thousand-kernel weight,and kernel number per plant,were negatively correlated with PCP.Our results demonstrated that inter-cultivar competition affects maize productivity,and increasing PCP will decrease translocation of assimilates to grain and,ultimately,reduce yield.Therefore,there is a negative correlation between population competitive intensity and yield performance in maize,breeders should develop a communal ideotype that would not perform well in competition in future.
文摘The growing stock assessment of three different teak forest stands (Tuirial: 500 m asl, Sairang: 200 m asl and Phunchawng: 550 m asl) was done in 2006 in Mizoram, India. Five diameter classes were arbitrarily established for knowing the volume attribute data and population structure, viz. a (10-20 cm), b (20-30 cm), c (30-40 cm), d (40-50 cm), and e (50-60 cm). Results revealed that the density of the individuals among the studied stands varied from 280 stems/ha to 620 stems/ha. The average diameter of all the individuals ranged between 27.48 cm and 35.43 cm. Similarly, the average height was oscillated between 17.87 m and 22.24 m. The total basal area was recorded between 24.28 m2.ha-1 and 45.80 m2.ha"l. The maximum and minimum values of total growing stock under all the diameter classes were 669.01 m3.ha-1 and 284.7 m3.ha-1, respectively. The representation of population structure of different stands explained that the perpetuation of this species was ensured for a quite long time.
文摘Background: The objective of the present study was to compare the relationship of anthropometric and physiometric characteristics using principal component factor analysis among three groups of type 2 diabetic subjects such as males, pre and postmenopausal females in North Indian Punjabi population. Method: A total of 349 type 2 diabetic subjects (males 157;females 192;88 pre and 104 postmenopausal) were ascertained for the present study. Different anthropometric and physiometric measurements were taken. Principal component factor analysis (PCFA) was applied to identify the components which are more close to type 2 diabetes among the three groups. Results: PCFA revealed five uncorrelated components which explained 79% of the total variance among diabetic males and six unrelated components which explained 78% of the total variance among pre and postmenopausal females. The important two factors could be identified as central obesity (factor 1) and blood pressure (factor 2) among these three groups. Conclusion: Higher clustering of obesity and blood pressures were found in diabetic males as com pared to pre and postmenopausal diabetic females in North Indian Punjabi population whereas, waist to hip ratio (WHR) has maximum loading in postmenopausal females as compared to others.
基金the financial assistance in the form of Senior Research Fellowship(09/013(0267)/2009-EMR-I).
文摘In this paper,a nonlinear mathematical model is proposed and analyzed to study the depletion of forestry resources caused simultaneously by population and population pressure augmented industrialization.The control of population pressure,using economic efforts is also considered in the modeling process.It is assumed that cumulative biomass density of forestry resources and the density of population follow logistic models.It is further assumed that the density of population and the level of industrialization increase as the cumulative biomass density of forestry resources increases.The cumulative density of economic efforts,which are applied to control the population pressure,is considered to be proportional to the population pressure.The model analysis shows that as the population pressure increases,the level of industrialization increases leading to decrease in the cumulative biomass density of forestry resources.It is found that if population pressure is controlled by using some economic efforts,the decrease in cumulative biomass density of forestry resources can be made much less than the case when no control is applied.It is also noted that if the population pressure augmented industrialization increases without control,the forestry resources may become extinct.
文摘Sub-Saharan Africa is currently undergoing an epidemiological transition from a disease burden largely attributable to communicable diseases to that resulting from a combination of both communicable and chronic non-communicable diseases.Data on chronic disease incidence,lifestyle,environmental and genetic risk factors are sparse in this region.This report aimed at providing relevant information in respect to risk factors that increase blood pressure and lead to development of intermediate cardiovascular phenotypes.We presented the rationale,objectives and key methodological features of the Nigerian Population Research on Environment,Gene and Health(NIPREGH) study.The challenges encountered in carrying out population study in this part of the world and the approaches at surmounting them were also presented.The preliminary data as at 20 November 2013 showed that out of the 205 individuals invited starting from early April 2013,160(72 women) consented and were enrolled;giving a response rate of 78%.Participants' age ranged from 18 to 80 years,with a mean(SD) of 39.8(12.4) years and they were of 34 different ethnic groups spread over 24 states out of the 36 states that constitute Nigeria.The mean(SD) of office and home blood pressures were 113.0(15.2) mm Hg systolic,73.5(12.5) mm Hg diastolic and 117.3(15.0) mm Hg systolic,and 76.0(9.6) mm Hg diastolic,respectively.Forty-three(26.8%) participants were hypertensive and 8(5.0%) were diabetic.In addition to having the unique potential of recruiting a cohort that is a true representative of the entire Nigerian population,NIPREGH is feasible and the objectives realisable.
文摘Objective To study the differences in blood pressure (BP) levels and the main factors raising BP among the population in Guangdong Province. Methods The data analyzed stem from the sampling survey of hypertension in Guangdong Province in 1991, covering 42, 894 subjects over 15 years old. Individual characteristics included age, sex, occupation, education, smoking, alcohol drinking and body mass index (BMI) . Results Systolic and diastolic BP increased with age. The hypertension prevalence rate in male is higher than in female. The age - adjusted prevalence rate in office personnel is the highest (12.9 % ) among all occupations. It was increased with education level and BMI (in people educated at university and over is 13. 1 % ), and higher in smokers and alcohol-drinkers than non-smokers and non -alcohol-drinkers. Conclusions Age, occupation, education, smoking, alcohol drinking and BMI all effect BP. These risk factors should be reduced in the Guangdong population.
文摘Although the Chinese government has published a seriesof favorable policies for textile industry,the outcome of thesefiscal policies in Chinese cotton machinery industry tends to besmall at this stage,since the effects of policies is hysteresial,and the industry had extended 2009 spring holiday amid thefinancial crisis.