This study investigated factors that influence employees’job satisfaction in China and whether they differ across age groups.Analysis was conducted using the 2014 China Labor-force Dynamics Survey,which included 6,24...This study investigated factors that influence employees’job satisfaction in China and whether they differ across age groups.Analysis was conducted using the 2014 China Labor-force Dynamics Survey,which included 6,249 employees in three age groups:634 aged 55 and older;2,569 aged 40-54;and 3,046 aged 18-39.The results indicate that when gender,age,marital status,living community type and education levels are controlled,total job satisfaction was associated with positive evaluations of income,job security,working environment,working time,promotion opportunity,job enjoyability,colleague relationships,ability and skills utilization,respect from others,and opportunities to express opinions.Regression analysis results indicate that age has positive effects on total job satisfaction.The older employees had the highest evaluations for job security,working environment,working time,income,job enjoyability,and total job satisfaction.The middle-aged employees had the highest evaluations for respect from others.The younger group had the highest evaluations for colleague relationships,ability and skills utilization,opportunities to express opinions,job enjoyability,promotion opportunity,and respect from others.Additionally,the older group did not value promotion opportunity,opportunities to express opinions,colleague relationships,ability and skills utilization,and respect from others.The findings highlight the importance of examining age related needs regarding how to improve employees’job satisfaction.The results suggest that employers should consider age-related challenges and needs in the workplace.展开更多
In Bahawalpur,a cross-sectional study assessed depression prevalence across age and gender groups,involving 442 participants from diverse socioeconomic backgrounds and settings.Utilizing the PHQ9 questionnaire,84%were...In Bahawalpur,a cross-sectional study assessed depression prevalence across age and gender groups,involving 442 participants from diverse socioeconomic backgrounds and settings.Utilizing the PHQ9 questionnaire,84%were found to meet depression levels.The findings revealed a higher incidence in females(88%)than males(79%),with the greatest disparity among young adults,particularly young women,due to factors like academic pressure and financial stress.School children had the lowest depression rates(68%),possibly due to better immunity.Elderly individuals exhibited more severe depression,likely related to aging and domestic challenges.The study’s findings highlight a significant variation in depression severity across different demographic groups,with an overall higher incidence in women.The research underscores the necessity for targeted mental health resources and interventions tailored to the specific needs of each demographic group.It also points to the importance of addressing academic and socioeconomic stressors to mitigate depression,particularly among young women.While the study provides valuable insights,it relies on self-reported data,which may introduce bias.Therefore,future research should include clinical assessments to validate these findings and ensure a more accurate representation of depression within the community.展开更多
There is an apparent contrast between children’s first language acquisition and adults’second language acquisition,which are mainly manifested in the following three aspects:age difference,difference in learning pro...There is an apparent contrast between children’s first language acquisition and adults’second language acquisition,which are mainly manifested in the following three aspects:age difference,difference in learning process and motivation difference.This paper will analyze these three differences in detail,and combine the analysis results to guide second language pedagogical implications according to the current situation.展开更多
Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages...Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages.At present,little is known about the size-and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of China.Here,we evaluated the photosynthetic and physiological responses of Artemisia ordosica Krasch.to drought stress using a field experiment in Mu Us Sandy Land,Ningxia Hui Autonomous Region,China in 2018.Rainfall was manipulated by installing outdoor shelters,with four rainfall treatments applied to 12 plots(5 m×5 m).There were four rainfall levels,including a control and rainfall reductions of 30%,50%and 70%,each with three replications.Taking individual crown size as the dividing basis,we measured the responses of A.ordosica photosynthetic and physiological responses to drought at different growth stages,i.e.,large-sized(>0.5 m^(2))and small-sized(≤0.5 m^(2))plants.The leaves of A.ordosica were divided into old leaves and young leaves for separate measurement.Results showed that:(1)under drought stress,the transfer efficiency of light energy captured by antenna pigments to the photosystem II(PSII)reaction center decreased,and the heat dissipation capacity increased simultaneously.To resist the photosynthetic system damage caused by drought,A.ordosica enhanced its free radical scavenging capacity by activating its antioxidant enzyme system;and(2)growth stage and leaf age had effects on the reaction of the photosynthetic system to drought.Small A.ordosica plants could not withstand severe drought stress(70%rainfall reduction),whereas large A.ordosica individuals could absorb deep soil water to ensure their survival in severe drought stressed condition.Under 30%and 50%rainfall reduction conditions,young leaves had a greater ability to resist drought than old leaves,whereas the latter were more resistant to severe drought stress.The response of A.ordosica photosynthetic system reflected the trade-off at different growth stages and leaf ages of photosynthetic production under different degrees of drought.This study provides a more comprehensive and systematic perspective for understanding the drought resistance mechanisms of desert plants.展开更多
Landfill leachates with different ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid si...Landfill leachates with different ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid size distribution and variations of leachate. These leachates were separated using micro-filtration and ultra-filtration into specific size fractions, i.e., suspended particles (SP) (〉 1.2 μm), coarse colloids (CC) (1.2-0.45 μm), fine colloids (FC) (0.45 m, 5 kDa/1 kDa molecular weight (MW)), and dissolved organic matters (DM, 〈 5 kDa/1 kDa MW). The specific colloids in each size fraction were quantified and characterized through chemical oxygen demands (COD), total solid (TS), pH, NH4^+-N, total organic carbon (TOC) and fixed solid (FS). It was found that COD, NH^4+-N and TS in leachate decreased significantly over ages, while pH increased. The dissolved fractions (〈 5 kDa/1 kDa) dominated (over 50%) in three leachates in terms of COD, and the organic matter content in dissolved fraction of leachates decreased and the inorganic matter increased as the disposal time extended, with the TOC/COD ratio 30%-7%. Dissolved fractions decreased from 82% to 40% in terms of TOC as the disposal time extended, suggested that the organic matter remained in leachate would form into middle molecular weight substances during the degradation process.展开更多
Rural-urban land conversion is a universal phenomenon in the rapid process of economic development and urban growth.The welfare of farmers who lost their farmland attracted a widespread concern within the society and ...Rural-urban land conversion is a universal phenomenon in the rapid process of economic development and urban growth.The welfare of farmers who lost their farmland attracted a widespread concern within the society and academia.However,further research about differentiated policies according to the characteristics of different farmer groups is still need to be conducted.This article divides the land-lost farmers into three age groups:younger than 45,45-65,and more than 65.It proposes a welfare index system including eight functional areas based on different age groups of affected farmers,taking four districts of Wuhan City as case study area.Fuzzy mathematics method is used to derive the aggregated welfare effect index.Our analysis show that the overall welfare levels of land-lost farmers of all age groups declined,but with a varying degree,with the level of welfare in those farmers who are 45-65 years old,younger than 45 years old,and older than 65 years old decreased by 18.7%,16.6%,and 12.7%,respectively.The direction and degree of effects on the functional activity index varies among different groups.Economic conditions,living environment,health,and social participation of all age groups decrease while social security and housing conditions increase.On the other hand,development opportunities,social communication,and leisure have different changing directions in different age stages.These results call for differentiated and tailor-made compensation policies for land-lost farmers,towards improving the welfare levels of all farmers and reduce the disparity among them.展开更多
This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the differe...This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the different tree species,ages and components,we sampled leaves,branches,stems,and roots,and measured the contents of Nitrogen,Phosphorus,Potassium,along with soil fertility.The changes of N,P,and K contents in the different tree species were studied,and the relationship between nutrient content and environmental factors was analyzed.The results indicated that the content of P in all three species was the lowest(0.039–0.28 g kg),while N content was the highest(0.095–1.72 g kg).As the terminal organ of nutrient transport,the nutrient content of leaves was the highest.P.armandii(0.45 g kg) had a higher nutrient concentration than P.tabulaeformis(0.19 g kg) and P.crassifolia(0.29 g kg).The nutrient content of each species was highest in a young forest,but lowest in a mature forest.The nutrient content of all three tree species was significantly affected by soil nutrient content,and negatively correlated with available soil nutrients.展开更多
The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossil...The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossils in the Upper Yunshan Formation of the Longzhaogou Group and the Lower Chengzihe For-mation of the Jixi Group, and the Qihulin Formation of the Longzhaogou Group yields Early Cretaceousbivalve and ammonite fossils. Consequently, the geological ages of the two groups are mainly, or even all, Ear-ly Cretaceous.展开更多
[Objectives]This study was conducted to investigate the photosynthetic physiological characteristics of Populus euphratica trees at different forest ages in the desert area of Minqin in response to drought stress.[Met...[Objectives]This study was conducted to investigate the photosynthetic physiological characteristics of Populus euphratica trees at different forest ages in the desert area of Minqin in response to drought stress.[Methods]With P.euphratica trees of different ages in Minqin as the research object,the water characteristics and photosynthetic physiological indexes(chlorophyll,soluble sugar,POD,SOD and MDA)were compared under different conditions.[Results]On the time gradient,the soil water contents of P.euphratica of different ages decreased continuously with the extension of irrigation stop time,but the decreases were small.Under the same stress treatment,the soil water contents of P.euphratica of different ages increased with the deepening of soil layer,but the differences were not significant(P>0.05).Under normal condition,the chlorophyll contents of P.euphratica at three ages gradually increased with the increase of age.The chlorophyll contents in leaves of P.euphratica at different ages were all lower under normal condition and higher under water stress.The changes of POD and SOD activity in leaves of P.euphratica at different ages under different conditions were basically the same,showing that the enzyme activity was higher under water stress than under normal under.The MDA contents in leaves of the young and middle P.euphratica forests were higher under water stress at 7 and 21 d than under normal condition,and the differences were not significant(P>0.05);and the MDA content in leaves of the mature P.euphratica forest was higher under water stress at 21 and 35 d than under normal condition.Drought stress has a certain effect on the photosynthetic physiological characteristics of P.euphratica.In summary,under drought stress,the chlorophyll content,SOD and POD activity,and MDA molar concentration in the leaves of P.euphratica were basically higher than under normal condition,indicating that P.euphratica could resist drought environment through osmotic adjustment and showed strong drought resistance.[Conclusions]This study provides a theoretical reference for the restoration,protection and reconstruction of natural P.euphratica forests in the desert area of Minqin.展开更多
The toxicity of acetaldehyde and age related changes on oxidoreductases in the liver,brain, kidney, and musele of female albino rats (Wistar strain) were studied. The specific activities of lactate [LDH], isocitrate [...The toxicity of acetaldehyde and age related changes on oxidoreductases in the liver,brain, kidney, and musele of female albino rats (Wistar strain) were studied. The specific activities of lactate [LDH], isocitrate [ICDH (NAD/NADP)], succinate [SDH], malate [MDH], glutamate [GDH] and glucose-6-Phosphate [G-6-PDH] dehydrogenases were signifieantly inereased as a function of age. However, acetaldehyde treatment significantly inhibited oxidoreductases in the tissues of 21, 90 and 180 day old rats. Liver enzymes of young (21 days) rats exhibited greater sensitivity to acetaldehyde toxicity. Similar inhibition of oxidoreductases in brain and kidney of adult (180 days) rats treated with acetaldehyde was observed. LDH and GDH as compared to other enzymes studied showed higher susceptibility to acetaldehyde toxicity. The differential sensitivity of tissues and inhibition of oxidoreductases by acetaldehyde as a function of age could be attributed to hypoxic conditions, energy crisis, and mitochondrial structural changes. The results suggest that acetaldehyde affects oxidation of glucose via HMP shuni pathway, glycolytic pathway and Krebs cycle resulting in the impairment of carbohydrate metabolism展开更多
The method of statistical analysis is employed in this paper to research the interests of online cadre learners, including learners from administrative organizations directly governed by the provincial government, Zun...The method of statistical analysis is employed in this paper to research the interests of online cadre learners, including learners from administrative organizations directly governed by the provincial government, Zunyi city and the state-owned enterprises directly governed by the provincial government in 2011 through the courseware of Guizhou Cadre Online Learning School. The difference in willingness to study in this manner between people of differing ages is examined through data analysis.展开更多
Objective To explore effects of decompressive craniectomy on cerebral blood flow volume and brain metabolism in different aged patients with severe traumatic brain injury. Methods 71 cases were divided into three grou...Objective To explore effects of decompressive craniectomy on cerebral blood flow volume and brain metabolism in different aged patients with severe traumatic brain injury. Methods 71 cases were divided into three groups according age: group A( 【 30 years) ,group B ( 30 ~ 50 years) 。展开更多
Despite the well-documented impacts of single natural hazards like earthquakes, less is known about the psychological adaptation to multiple natural hazards, particularly in rural areas. This study investigated the as...Despite the well-documented impacts of single natural hazards like earthquakes, less is known about the psychological adaptation to multiple natural hazards, particularly in rural areas. This study investigated the associations of multiple natural hazards with depression among Chinese adults. Data were retrieved from the China Family Panel Studies conducted during 2010–2018. With a sample of 11,633 Chinese adults, multilevel logistic regression was employed to examine the relationships between natural hazard exposure and depression in the total sample and different age groups. Overall, experiencing four or more natural hazards was associated with a higher risk of being depressed. Regarding hazard type, the number of hydrometeorological and biological hazards was associated with a higher likelihood of depression, whereas the number of geologic and other hazards was related to a lower risk of depression. Middle-aged adults from villages were more likely to be affected by natural hazard exposure than older and younger adults. The findings of this study show that cumulative exposure to natural hazards can generate lasting effects on depressive symptoms, particularly in middle adulthood. The findings also suggest that older adults from rural areas may have accumulated more resilience to mitigate the adverse well-being effects of hazard events. Policies and interventions should enhance disaster awareness and preparation for aging residents from multi-hazard communities.展开更多
This paper asks whether the turbulence of the Covid-19 lockdowns has left enduring changes to everyday life in the UK which are unlikely to have happened,up to now,in the absence of the pandemic.The analysis disaggreg...This paper asks whether the turbulence of the Covid-19 lockdowns has left enduring changes to everyday life in the UK which are unlikely to have happened,up to now,in the absence of the pandemic.The analysis disaggregates the UK population by gender,and into age groups and income bands,specifies whose lives were changed during the lockdowns,and exactly how.It is argued that most changes from pre-to post-lockdowns have been spurts in longer-running trends driven by the UK demographic,housing,economic and political contexts.The exceptions,the sole genuine lockdown legacies that the analysis leaves,are the normalisation of working from home and an increase in total time spent doing paid work.展开更多
Aim: To evaluate the characteristics of semen produced by one- and two-years old White Italian ganders duringentire reproductive season, in order to clarify whether the young ganders are responsible for a low fertilit...Aim: To evaluate the characteristics of semen produced by one- and two-years old White Italian ganders duringentire reproductive season, in order to clarify whether the young ganders are responsible for a low fertility rate in yougeese. Methods: Males were kept individually in cages under natural light. Semen was collected by dorso-abdonhal massage three times a week and routine examination was performed. Results: The mean ejaculate volume (2and 1.6 mL, respectively) and sperm concentration (323 and 281 × 10~6/mL, respectively) in one-year-old gandwere higher than those of two-year-old ones. The percentages viable spermatozoa of one- and two-year-old gandwere similar (91.4 and 92.3%, respectively), but the percentage of normally formed viable spermatozoa was signicantly higher in the older ganders than in the younger (47.8 and 42.9%, respectively, P < 0.05). Conclusion:The semina from one- or two-year-old Ganders were similar in regard to volume, sperm density and sperm motility,the percentage of normally formed viable spermatozoa, which is critical for fertilization, was significantly higher inolder ganders. It appears that the ganders are responsible for the low fertility rate in young geese.展开更多
In the post-Covid-19 pandemic era,it is more difficult for some Chinese schools in Europe to provide online extra classes for overseas Chinese children after school hours,as they did previously.To meet students'mu...In the post-Covid-19 pandemic era,it is more difficult for some Chinese schools in Europe to provide online extra classes for overseas Chinese children after school hours,as they did previously.To meet students'multifaceted learning needs,online extra classes teaching,including online Chinese language classes and some online art classes,is increasingly being offered as a supplement to the diversity of teaching activities in Chinese schools in Europe,with the ultimate goal of improving the learning abilities of overseas Chinese children while relieving pressure on teaching resources in schools.Children’s learning self-efficacy in online extracurricular courses has its own uniqueness,which can be considered from three dimensions,including learning confidence,learning ability,and self-assessment ability.This study aims to examine the factors influencing the self-efficacy of overseas Chinese children and to make optimization suggestions for better teaching methods.In search of that,an online questionnaire survey with 127 participants from overseas Chinese children agedtowas collected.The findings indicate that the role of learning confidence in overseas Chinese children outweighs their learning ability and self-assessment ability.Gender and age have a negligible effect on self-efficacy but have an impact on learning confidence.Chinese schools in Europe do not need to show gender differences when conducting classroom activities in online teaching to improve the online self-efficacy of Chinese children,and efforts should also be made to keep the courage of older students to trial and error.Teachers are expected to investigate more aspects of their students'personalities in future classrooms rather than sticking to a consistent and unchanging teaching model.展开更多
The COVID-19 pandemic has not only affected the world in terms of their physical health but has also been a strain on our mental well-being.Individuals who have showcased the tendency to bounce back from this situatio...The COVID-19 pandemic has not only affected the world in terms of their physical health but has also been a strain on our mental well-being.Individuals who have showcased the tendency to bounce back from this situation have been real survivors of this pandemic.With this background in mind,this research aimed to study the gender differences and age differences in stress resilience.The Stress Resiliency Profile by Thomas and Tymon(1992),Jr.was used for this purpose.An equal number of males and females(n=60;N=120)were evaluated for the study.To assess the age differences,the participants were divided into two age groups:15-22 years and 22-30 years of age.There were an equal number of individuals in each group(n=60,N=120).The subjects were assessed on the three dimensions of Stress Resiliency Profile-Necessitating,Skill Recognition and Deficiency Focusing.Results indicated significant differences in the Deficiency Focusing dimension among males and females.In the age difference evaluation,significant differences were found in the Skill Recognition dimension.The findings have been discussed within the framework of previous research.The current research findings have significant implications for the study of stress and resilience.展开更多
To investigate plant biomass and nutrient distribution and accumulation in organs of Alnus cremastogyne at different ages from 1 to 4 years, the biomass, N, P, K, Ca, Mg, Fe and Zn were tested. The results showed that...To investigate plant biomass and nutrient distribution and accumulation in organs of Alnus cremastogyne at different ages from 1 to 4 years, the biomass, N, P, K, Ca, Mg, Fe and Zn were tested. The results showed that the average biomass of the whole tree and the biomass of leaf, branch, stem, and root were in positive correlation with tree age, but the growth rate of biomass had a decreasing trend with the tree age increasing, and only the biomass proportion of the trunk in the whole individual plant showed an increasing trend with age. The contents of nutrient elements in organs showed an order of N 〉 Ca 〉 K 〉 Mg 〉 P 〉 Fe 〉 Zn ; and the contents of N, P and K were higher in the leaf than in other organs, and the contents of Ca, Mg and Fe in the root were higher than in other organs. The accumulations of N, P, K, Ca, Mg and Zn were the highest in the trunk, and that of Fe was the highest in the root. The annual net accumulations of N, P, K, Ca and Mg in the average trees from 1 to 4 years old were 17.07, 40.79, 95.82 and 106.71 g, respectively, and the annual net accumulations of microelements (Fe and Zn) were 335.04, 577.26, 1267 and 1525.27 mg, respectively.展开更多
Background Severe cases of coronavirus disease 2019(COVID-19)among pediatric patients are more common in children less than 1 year of age.Our aim is to address the underlying role of immunity and inflammation conditio...Background Severe cases of coronavirus disease 2019(COVID-19)among pediatric patients are more common in children less than 1 year of age.Our aim is to address the underlying role of immunity and inflammation conditions among different age groups of pediatric patients.Methods We recruited pediatric patients confirmed of moderate COVID-19 symptoms,admitted to Wuhan Children's Hospital from January 28th to April 1st in 2020.Patients were divided into four age groups(≤1,1–6,7–10,and 11–15 years).Demographic information,clinical characteristics,laboratory results of lymphocyte subsets test,immune and inflammation related markers were all evaluated.Results Analysis included 217/241(90.0%)of patients with moderate clinical stage disease.Average recovery time of children more than 6 years old was significantly shorter than of children younger than 6 years(P=0.001).Reduced neutrophils and increased lymphocytes were significantly most observed among patients under 1 year old(P<0.01).CD19+B cells were the only significantly elevated immune cells,especially among patients under 1 year old(cell proportion:n=12,30.0%,P<0.001;cell count:n=13,32.5%,P<0.001).While,low levels of immune related makers,such as immunoglobulin(Ig)G(P<0.001),IgA(P<0.001),IgM(P<0.001)and serum complement C3c(P<0.001),were also mostly found among patients under 1 year old,together with elevated levels of inflammation related markers,such as tumor necrosis factor γ (P=0.007),interleukin(IL)-10(P=0.011),IL-6(P=0.008),lactate dehydrogenase(P<0.001),and procalcitonin(P=0.007).Conclusion The higher rate of severe cases and long course of COVID-19 among children under 1 year old may be due to the lower production of antibodies and serum complements of in this age group.展开更多
基金The National Social Science Fund of China“Research on Labor Relations Situation and Social Work Intervention in the Pearl River Delta under the New Normal”(16CSH035).
文摘This study investigated factors that influence employees’job satisfaction in China and whether they differ across age groups.Analysis was conducted using the 2014 China Labor-force Dynamics Survey,which included 6,249 employees in three age groups:634 aged 55 and older;2,569 aged 40-54;and 3,046 aged 18-39.The results indicate that when gender,age,marital status,living community type and education levels are controlled,total job satisfaction was associated with positive evaluations of income,job security,working environment,working time,promotion opportunity,job enjoyability,colleague relationships,ability and skills utilization,respect from others,and opportunities to express opinions.Regression analysis results indicate that age has positive effects on total job satisfaction.The older employees had the highest evaluations for job security,working environment,working time,income,job enjoyability,and total job satisfaction.The middle-aged employees had the highest evaluations for respect from others.The younger group had the highest evaluations for colleague relationships,ability and skills utilization,opportunities to express opinions,job enjoyability,promotion opportunity,and respect from others.Additionally,the older group did not value promotion opportunity,opportunities to express opinions,colleague relationships,ability and skills utilization,and respect from others.The findings highlight the importance of examining age related needs regarding how to improve employees’job satisfaction.The results suggest that employers should consider age-related challenges and needs in the workplace.
文摘In Bahawalpur,a cross-sectional study assessed depression prevalence across age and gender groups,involving 442 participants from diverse socioeconomic backgrounds and settings.Utilizing the PHQ9 questionnaire,84%were found to meet depression levels.The findings revealed a higher incidence in females(88%)than males(79%),with the greatest disparity among young adults,particularly young women,due to factors like academic pressure and financial stress.School children had the lowest depression rates(68%),possibly due to better immunity.Elderly individuals exhibited more severe depression,likely related to aging and domestic challenges.The study’s findings highlight a significant variation in depression severity across different demographic groups,with an overall higher incidence in women.The research underscores the necessity for targeted mental health resources and interventions tailored to the specific needs of each demographic group.It also points to the importance of addressing academic and socioeconomic stressors to mitigate depression,particularly among young women.While the study provides valuable insights,it relies on self-reported data,which may introduce bias.Therefore,future research should include clinical assessments to validate these findings and ensure a more accurate representation of depression within the community.
文摘There is an apparent contrast between children’s first language acquisition and adults’second language acquisition,which are mainly manifested in the following three aspects:age difference,difference in learning process and motivation difference.This paper will analyze these three differences in detail,and combine the analysis results to guide second language pedagogical implications according to the current situation.
基金This research was supported by the National Natural Science Foundation of China(31700639)the National Key Research and Development Program of China(2018YFC0507102,2016YFC0500905).
文摘Drought is one of the most significant natural disasters in the arid and semi-arid areas of China.Populations or plant organs often differ in their responses to drought and other adversities at different growth stages.At present,little is known about the size-and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of China.Here,we evaluated the photosynthetic and physiological responses of Artemisia ordosica Krasch.to drought stress using a field experiment in Mu Us Sandy Land,Ningxia Hui Autonomous Region,China in 2018.Rainfall was manipulated by installing outdoor shelters,with four rainfall treatments applied to 12 plots(5 m×5 m).There were four rainfall levels,including a control and rainfall reductions of 30%,50%and 70%,each with three replications.Taking individual crown size as the dividing basis,we measured the responses of A.ordosica photosynthetic and physiological responses to drought at different growth stages,i.e.,large-sized(>0.5 m^(2))and small-sized(≤0.5 m^(2))plants.The leaves of A.ordosica were divided into old leaves and young leaves for separate measurement.Results showed that:(1)under drought stress,the transfer efficiency of light energy captured by antenna pigments to the photosystem II(PSII)reaction center decreased,and the heat dissipation capacity increased simultaneously.To resist the photosynthetic system damage caused by drought,A.ordosica enhanced its free radical scavenging capacity by activating its antioxidant enzyme system;and(2)growth stage and leaf age had effects on the reaction of the photosynthetic system to drought.Small A.ordosica plants could not withstand severe drought stress(70%rainfall reduction),whereas large A.ordosica individuals could absorb deep soil water to ensure their survival in severe drought stressed condition.Under 30%and 50%rainfall reduction conditions,young leaves had a greater ability to resist drought than old leaves,whereas the latter were more resistant to severe drought stress.The response of A.ordosica photosynthetic system reflected the trade-off at different growth stages and leaf ages of photosynthetic production under different degrees of drought.This study provides a more comprehensive and systematic perspective for understanding the drought resistance mechanisms of desert plants.
基金supported by the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No.PCRRF09008)the Key Project of Science and Technology Commission of Shanghai Municipality (No.08Dz1202800)
文摘Landfill leachates with different ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid size distribution and variations of leachate. These leachates were separated using micro-filtration and ultra-filtration into specific size fractions, i.e., suspended particles (SP) (〉 1.2 μm), coarse colloids (CC) (1.2-0.45 μm), fine colloids (FC) (0.45 m, 5 kDa/1 kDa molecular weight (MW)), and dissolved organic matters (DM, 〈 5 kDa/1 kDa MW). The specific colloids in each size fraction were quantified and characterized through chemical oxygen demands (COD), total solid (TS), pH, NH4^+-N, total organic carbon (TOC) and fixed solid (FS). It was found that COD, NH^4+-N and TS in leachate decreased significantly over ages, while pH increased. The dissolved fractions (〈 5 kDa/1 kDa) dominated (over 50%) in three leachates in terms of COD, and the organic matter content in dissolved fraction of leachates decreased and the inorganic matter increased as the disposal time extended, with the TOC/COD ratio 30%-7%. Dissolved fractions decreased from 82% to 40% in terms of TOC as the disposal time extended, suggested that the organic matter remained in leachate would form into middle molecular weight substances during the degradation process.
基金supported by National Natural Science Foundation of China(71003041)the Fundamental Research Funds of the Central Universities(2662015PY198)
文摘Rural-urban land conversion is a universal phenomenon in the rapid process of economic development and urban growth.The welfare of farmers who lost their farmland attracted a widespread concern within the society and academia.However,further research about differentiated policies according to the characteristics of different farmer groups is still need to be conducted.This article divides the land-lost farmers into three age groups:younger than 45,45-65,and more than 65.It proposes a welfare index system including eight functional areas based on different age groups of affected farmers,taking four districts of Wuhan City as case study area.Fuzzy mathematics method is used to derive the aggregated welfare effect index.Our analysis show that the overall welfare levels of land-lost farmers of all age groups declined,but with a varying degree,with the level of welfare in those farmers who are 45-65 years old,younger than 45 years old,and older than 65 years old decreased by 18.7%,16.6%,and 12.7%,respectively.The direction and degree of effects on the functional activity index varies among different groups.Economic conditions,living environment,health,and social participation of all age groups decrease while social security and housing conditions increase.On the other hand,development opportunities,social communication,and leisure have different changing directions in different age stages.These results call for differentiated and tailor-made compensation policies for land-lost farmers,towards improving the welfare levels of all farmers and reduce the disparity among them.
基金supported by the Special Fund for Forestry Scientific Research in the Public Interest(No.201204101-4)National Natural Science Foundation of China(No.31260141)CFERN and GENE Award Funds on Ecological Papers
文摘This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the different tree species,ages and components,we sampled leaves,branches,stems,and roots,and measured the contents of Nitrogen,Phosphorus,Potassium,along with soil fertility.The changes of N,P,and K contents in the different tree species were studied,and the relationship between nutrient content and environmental factors was analyzed.The results indicated that the content of P in all three species was the lowest(0.039–0.28 g kg),while N content was the highest(0.095–1.72 g kg).As the terminal organ of nutrient transport,the nutrient content of leaves was the highest.P.armandii(0.45 g kg) had a higher nutrient concentration than P.tabulaeformis(0.19 g kg) and P.crassifolia(0.29 g kg).The nutrient content of each species was highest in a young forest,but lowest in a mature forest.The nutrient content of all three tree species was significantly affected by soil nutrient content,and negatively correlated with available soil nutrients.
基金Director Foundation of Nanjing Institute of Geology and Palaeontology,Academin Sinica.
文摘The age of the Longzhaogou and Jixi Groups of coal measures in eastern Heilongjiang were previouslyconsidered to be Jurassic or mainly Jurassic. But there occur Middle Barremian-Early Albian Aucellina(bivalvia) fossils in the Upper Yunshan Formation of the Longzhaogou Group and the Lower Chengzihe For-mation of the Jixi Group, and the Qihulin Formation of the Longzhaogou Group yields Early Cretaceousbivalve and ammonite fossils. Consequently, the geological ages of the two groups are mainly, or even all, Ear-ly Cretaceous.
基金Supported by Research and Development Program of Gansu Province(17YF1FA113)The National Natural Science Foundation of China(31560128).
文摘[Objectives]This study was conducted to investigate the photosynthetic physiological characteristics of Populus euphratica trees at different forest ages in the desert area of Minqin in response to drought stress.[Methods]With P.euphratica trees of different ages in Minqin as the research object,the water characteristics and photosynthetic physiological indexes(chlorophyll,soluble sugar,POD,SOD and MDA)were compared under different conditions.[Results]On the time gradient,the soil water contents of P.euphratica of different ages decreased continuously with the extension of irrigation stop time,but the decreases were small.Under the same stress treatment,the soil water contents of P.euphratica of different ages increased with the deepening of soil layer,but the differences were not significant(P>0.05).Under normal condition,the chlorophyll contents of P.euphratica at three ages gradually increased with the increase of age.The chlorophyll contents in leaves of P.euphratica at different ages were all lower under normal condition and higher under water stress.The changes of POD and SOD activity in leaves of P.euphratica at different ages under different conditions were basically the same,showing that the enzyme activity was higher under water stress than under normal under.The MDA contents in leaves of the young and middle P.euphratica forests were higher under water stress at 7 and 21 d than under normal condition,and the differences were not significant(P>0.05);and the MDA content in leaves of the mature P.euphratica forest was higher under water stress at 21 and 35 d than under normal condition.Drought stress has a certain effect on the photosynthetic physiological characteristics of P.euphratica.In summary,under drought stress,the chlorophyll content,SOD and POD activity,and MDA molar concentration in the leaves of P.euphratica were basically higher than under normal condition,indicating that P.euphratica could resist drought environment through osmotic adjustment and showed strong drought resistance.[Conclusions]This study provides a theoretical reference for the restoration,protection and reconstruction of natural P.euphratica forests in the desert area of Minqin.
文摘The toxicity of acetaldehyde and age related changes on oxidoreductases in the liver,brain, kidney, and musele of female albino rats (Wistar strain) were studied. The specific activities of lactate [LDH], isocitrate [ICDH (NAD/NADP)], succinate [SDH], malate [MDH], glutamate [GDH] and glucose-6-Phosphate [G-6-PDH] dehydrogenases were signifieantly inereased as a function of age. However, acetaldehyde treatment significantly inhibited oxidoreductases in the tissues of 21, 90 and 180 day old rats. Liver enzymes of young (21 days) rats exhibited greater sensitivity to acetaldehyde toxicity. Similar inhibition of oxidoreductases in brain and kidney of adult (180 days) rats treated with acetaldehyde was observed. LDH and GDH as compared to other enzymes studied showed higher susceptibility to acetaldehyde toxicity. The differential sensitivity of tissues and inhibition of oxidoreductases by acetaldehyde as a function of age could be attributed to hypoxic conditions, energy crisis, and mitochondrial structural changes. The results suggest that acetaldehyde affects oxidation of glucose via HMP shuni pathway, glycolytic pathway and Krebs cycle resulting in the impairment of carbohydrate metabolism
文摘The method of statistical analysis is employed in this paper to research the interests of online cadre learners, including learners from administrative organizations directly governed by the provincial government, Zunyi city and the state-owned enterprises directly governed by the provincial government in 2011 through the courseware of Guizhou Cadre Online Learning School. The difference in willingness to study in this manner between people of differing ages is examined through data analysis.
文摘Objective To explore effects of decompressive craniectomy on cerebral blood flow volume and brain metabolism in different aged patients with severe traumatic brain injury. Methods 71 cases were divided into three groups according age: group A( 【 30 years) ,group B ( 30 ~ 50 years) 。
基金supported by the National Social Science Fund of China (Grant No. 23CSH035)the Reaching Out Award from the Hong Kong Special Administrative Region Government Scholarship Fund+1 种基金the Additional Top Conference Grantthe Research Student Attachment Programme (RSAP) from The Hong Kong Polytechnic University。
文摘Despite the well-documented impacts of single natural hazards like earthquakes, less is known about the psychological adaptation to multiple natural hazards, particularly in rural areas. This study investigated the associations of multiple natural hazards with depression among Chinese adults. Data were retrieved from the China Family Panel Studies conducted during 2010–2018. With a sample of 11,633 Chinese adults, multilevel logistic regression was employed to examine the relationships between natural hazard exposure and depression in the total sample and different age groups. Overall, experiencing four or more natural hazards was associated with a higher risk of being depressed. Regarding hazard type, the number of hydrometeorological and biological hazards was associated with a higher likelihood of depression, whereas the number of geologic and other hazards was related to a lower risk of depression. Middle-aged adults from villages were more likely to be affected by natural hazard exposure than older and younger adults. The findings of this study show that cumulative exposure to natural hazards can generate lasting effects on depressive symptoms, particularly in middle adulthood. The findings also suggest that older adults from rural areas may have accumulated more resilience to mitigate the adverse well-being effects of hazard events. Policies and interventions should enhance disaster awareness and preparation for aging residents from multi-hazard communities.
文摘This paper asks whether the turbulence of the Covid-19 lockdowns has left enduring changes to everyday life in the UK which are unlikely to have happened,up to now,in the absence of the pandemic.The analysis disaggregates the UK population by gender,and into age groups and income bands,specifies whose lives were changed during the lockdowns,and exactly how.It is argued that most changes from pre-to post-lockdowns have been spurts in longer-running trends driven by the UK demographic,housing,economic and political contexts.The exceptions,the sole genuine lockdown legacies that the analysis leaves,are the normalisation of working from home and an increase in total time spent doing paid work.
文摘Aim: To evaluate the characteristics of semen produced by one- and two-years old White Italian ganders duringentire reproductive season, in order to clarify whether the young ganders are responsible for a low fertility rate in yougeese. Methods: Males were kept individually in cages under natural light. Semen was collected by dorso-abdonhal massage three times a week and routine examination was performed. Results: The mean ejaculate volume (2and 1.6 mL, respectively) and sperm concentration (323 and 281 × 10~6/mL, respectively) in one-year-old gandwere higher than those of two-year-old ones. The percentages viable spermatozoa of one- and two-year-old gandwere similar (91.4 and 92.3%, respectively), but the percentage of normally formed viable spermatozoa was signicantly higher in the older ganders than in the younger (47.8 and 42.9%, respectively, P < 0.05). Conclusion:The semina from one- or two-year-old Ganders were similar in regard to volume, sperm density and sperm motility,the percentage of normally formed viable spermatozoa, which is critical for fertilization, was significantly higher inolder ganders. It appears that the ganders are responsible for the low fertility rate in young geese.
基金This paper is funded by research project of National College Student Innovation and Entrepreneurship Project of Wenzhou University in 2022,“A Study of Teaching Practices and Validity of Online Extra Classes of Chinese Schools in Europe”under Project No.202210351019 and research project of Wenzhou University Student Scientific Research Project(“Challenge Cup”Special Project)in 2022“Qiaozhiqiao-Chinese Ethnic Identity Education of Overseas Chinese Children”under Project No.2022kx220.
文摘In the post-Covid-19 pandemic era,it is more difficult for some Chinese schools in Europe to provide online extra classes for overseas Chinese children after school hours,as they did previously.To meet students'multifaceted learning needs,online extra classes teaching,including online Chinese language classes and some online art classes,is increasingly being offered as a supplement to the diversity of teaching activities in Chinese schools in Europe,with the ultimate goal of improving the learning abilities of overseas Chinese children while relieving pressure on teaching resources in schools.Children’s learning self-efficacy in online extracurricular courses has its own uniqueness,which can be considered from three dimensions,including learning confidence,learning ability,and self-assessment ability.This study aims to examine the factors influencing the self-efficacy of overseas Chinese children and to make optimization suggestions for better teaching methods.In search of that,an online questionnaire survey with 127 participants from overseas Chinese children agedtowas collected.The findings indicate that the role of learning confidence in overseas Chinese children outweighs their learning ability and self-assessment ability.Gender and age have a negligible effect on self-efficacy but have an impact on learning confidence.Chinese schools in Europe do not need to show gender differences when conducting classroom activities in online teaching to improve the online self-efficacy of Chinese children,and efforts should also be made to keep the courage of older students to trial and error.Teachers are expected to investigate more aspects of their students'personalities in future classrooms rather than sticking to a consistent and unchanging teaching model.
文摘The COVID-19 pandemic has not only affected the world in terms of their physical health but has also been a strain on our mental well-being.Individuals who have showcased the tendency to bounce back from this situation have been real survivors of this pandemic.With this background in mind,this research aimed to study the gender differences and age differences in stress resilience.The Stress Resiliency Profile by Thomas and Tymon(1992),Jr.was used for this purpose.An equal number of males and females(n=60;N=120)were evaluated for the study.To assess the age differences,the participants were divided into two age groups:15-22 years and 22-30 years of age.There were an equal number of individuals in each group(n=60,N=120).The subjects were assessed on the three dimensions of Stress Resiliency Profile-Necessitating,Skill Recognition and Deficiency Focusing.Results indicated significant differences in the Deficiency Focusing dimension among males and females.In the age difference evaluation,significant differences were found in the Skill Recognition dimension.The findings have been discussed within the framework of previous research.The current research findings have significant implications for the study of stress and resilience.
基金Supported by Project of Science and Technology Department in Sichuan Province(2016NZ0043)
文摘To investigate plant biomass and nutrient distribution and accumulation in organs of Alnus cremastogyne at different ages from 1 to 4 years, the biomass, N, P, K, Ca, Mg, Fe and Zn were tested. The results showed that the average biomass of the whole tree and the biomass of leaf, branch, stem, and root were in positive correlation with tree age, but the growth rate of biomass had a decreasing trend with the tree age increasing, and only the biomass proportion of the trunk in the whole individual plant showed an increasing trend with age. The contents of nutrient elements in organs showed an order of N 〉 Ca 〉 K 〉 Mg 〉 P 〉 Fe 〉 Zn ; and the contents of N, P and K were higher in the leaf than in other organs, and the contents of Ca, Mg and Fe in the root were higher than in other organs. The accumulations of N, P, K, Ca, Mg and Zn were the highest in the trunk, and that of Fe was the highest in the root. The annual net accumulations of N, P, K, Ca and Mg in the average trees from 1 to 4 years old were 17.07, 40.79, 95.82 and 106.71 g, respectively, and the annual net accumulations of microelements (Fe and Zn) were 335.04, 577.26, 1267 and 1525.27 mg, respectively.
文摘Background Severe cases of coronavirus disease 2019(COVID-19)among pediatric patients are more common in children less than 1 year of age.Our aim is to address the underlying role of immunity and inflammation conditions among different age groups of pediatric patients.Methods We recruited pediatric patients confirmed of moderate COVID-19 symptoms,admitted to Wuhan Children's Hospital from January 28th to April 1st in 2020.Patients were divided into four age groups(≤1,1–6,7–10,and 11–15 years).Demographic information,clinical characteristics,laboratory results of lymphocyte subsets test,immune and inflammation related markers were all evaluated.Results Analysis included 217/241(90.0%)of patients with moderate clinical stage disease.Average recovery time of children more than 6 years old was significantly shorter than of children younger than 6 years(P=0.001).Reduced neutrophils and increased lymphocytes were significantly most observed among patients under 1 year old(P<0.01).CD19+B cells were the only significantly elevated immune cells,especially among patients under 1 year old(cell proportion:n=12,30.0%,P<0.001;cell count:n=13,32.5%,P<0.001).While,low levels of immune related makers,such as immunoglobulin(Ig)G(P<0.001),IgA(P<0.001),IgM(P<0.001)and serum complement C3c(P<0.001),were also mostly found among patients under 1 year old,together with elevated levels of inflammation related markers,such as tumor necrosis factor γ (P=0.007),interleukin(IL)-10(P=0.011),IL-6(P=0.008),lactate dehydrogenase(P<0.001),and procalcitonin(P=0.007).Conclusion The higher rate of severe cases and long course of COVID-19 among children under 1 year old may be due to the lower production of antibodies and serum complements of in this age group.