Background:Midlife lifestyle factors,including physical activity,are associated with late-life brain health,yet the role of aerobic exercise on structural brain health in early and mid-adulthood remains poorly underst...Background:Midlife lifestyle factors,including physical activity,are associated with late-life brain health,yet the role of aerobic exercise on structural brain health in early and mid-adulthood remains poorly understood.This study aimed to examine the effect of aerobic exercise on structural brain age and to explore potential mediators.Methods:In a single-blind,12-month randomized clinical trial,130 healthy participants aged 26-58 years were randomized into a moderate-to-vigorous intensity aerobic exercise group or a usual-care control group.The exercise group attended two supervised 60-min sessions per week in a laboratory setting plus engaged in home-based exercise to achieve 150 min of exercise per week.Brain-predicted age difference(brain-PAD)and cardiorespiratory fitness(CRF)were assessed at baseline and 12 months.Both intention-to-treat(ITT)and completers analyses(including participants who completed post-intervention assessments)were performed.Results:The 130 participants(67.7%female)had an age of 41.28±9.93 years(mean±SD).At baseline,higher CRF(peak oxygen uptake,VO_(2peak))was associated with smaller brain-PAD(β=-0.309,p=0.012).After the intervention,the exercise group showed a decrease in brainPAD(estimated mean difference(EMD)=-0.60;95%confidence interval(95%CI):-1.15 to-0.04;p=0.034)compared to the control group(EMD=0.35;95%CI:-0.21 to 0.92;p=0.217);time×group interaction(between-group difference(BGD)=-0.95;95%CI:-1.72 to-0.17;p=0.019).VO2peak improved in the exercise group(EMD=1.60;95%CI:0.29-2.90;p=0.017)compared to the control group(EMD=-0.78;95%CI:-2.17 to 0.60;p=0.265);time×group interaction(BGD=2.38;95%CI:0.52-4.25;p=0.015).Body composition,blood pressure,and brain-derived neurotrophic factor levels were unaffected.None of the proposed pathways statistically mediated the effect of exercise on brain-PAD.The results from completers were similar.Conclusion:Engaging in 12 months of moderate-to-vigorous exercise reduced brain-PAD in early-to-midlife adults.The pathways by which these effects occur remain unknown.展开更多
Energy expenditure estimation can be used to measure the exercise load and physical condition of different individuals, such as soldiers, athletes, firemen, etc., during their training and work. Energy expenditure est...Energy expenditure estimation can be used to measure the exercise load and physical condition of different individuals, such as soldiers, athletes, firemen, etc., during their training and work. Energy expenditure estimation methods based on computer vision have rapidly developed in recent years. Compared with sensor-based methods, such methods are capable of monitoring several target persons at the same time, and the subjects do not need to wear different sensor devices that hamper their movement. In this paper, we propose a cross-attention spatial–temporal convolutional neural network to predict the energy expenditure of people under different exercise intensities. The model explores the relationship between changes in the human skeleton and energy expenditure intensity. In addition, a cross-attention correction module is used to reduce the negative effects of individual physical fitness characteristics during energy expenditure estimation. The experimental results show that our proposed method achieves high accuracy for energy expenditure estimation and performs better than existing computer vision-based energy expenditure estimation methods do. The proposed method can be widely used in various physical activity scenarios to measure energy expenditure, increasing the convenience of usage.展开更多
Measuring cardiorespiratory fitness(CRF)is an important predictor of morbidity and mortality in epidemiological studies and clinical settings.1 However,the feasibility of measuring maximal CRF is low due to the time,e...Measuring cardiorespiratory fitness(CRF)is an important predictor of morbidity and mortality in epidemiological studies and clinical settings.1 However,the feasibility of measuring maximal CRF is low due to the time,equipment,and expertise needed to conduct laboratory cardiopulmonary exercise testing(CPET)to determine the maximal rate of oxygen uptake(VO2max)as an objective measure of CRF.Alternatively,indirect estimates of CRF have been applied by measuring maximal duration on treadmill or cycle ergometer tests,2,3 extrapolating maximal CRF from workload or heart rate during submaximal fitness tests,4,5 and using non-exercise algorithms to estimate CRF from an individual’s age,sex,body mass,and physical activity habits.6 It is assumed that objectively measured VO2max is superior to extrapolated and estimated values due to errors associated with the estimated values;7,8 however,until Singh et al.9 newly released article in the Journal of Sport and Health Science,the comparability of these methods in identifying risks for all-cause and cardiovascular disease(CVD)mortality was unknown.展开更多
Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit interna...Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit international monitoring and surveillance.The objective of the study was to seek international consensus on a proposed,evidence-informed,Youth Fitness International Test(YFIT)battery and protocols for health monitoring and surveillance in children and adolescents aged 618 years.Methods:We conducted an international modified Delphi study to evaluate the level of agreement with a proposed,evidence-based,YFIT of core health-relatedfitness tests and protocols to be used worldwide in 6-to 18-year-olds.This proposal was based on previous European and North American projects that systematically reviewed the existing evidence to identify the most valid,reliable,health-related,safe,and feasiblefitness tests to be used in children and adolescents aged 618 years.We designed a single-panel modified Delphi study and invited 216 experts from all around the world to answer this Delphi survey,of whom one-third are from low-to-middle income countries and one-third are women.Four experts were involved in the piloting of the survey and did not participate in the main Delphi study to avoid bias.We pre-defined an agreement of 80%among the expert participants to achieve consensus.Results:We obtained a high response rate(78%)with a total of 169fitness experts from 50 countries and territories,including 63 women and 61 experts from low-or middle-income countries/territories.Consensus(>85%agreement)was achieved for all proposed tests and protocols,supporting the YFIT battery,which includes weight and height(to compute body mass index as a proxy of body size/composition),the 20-m shuttle run(cardiorespiratoryfitness),handgrip strength,and standing long jump(muscularfitness).Conclusion:This study contributes to standardizingfitness tests and protocols used for research,monitoring,and surveillance across the world,which will allow for future data pooling and the development of international and regional sex-and age-specific reference values,health-related cut-points,and a global picture offitness among children and adolescents.展开更多
Objective To study the increasing use of sports and fitness APPs against the background of national fitness and post-epidemic era,and to provide some suggestions for the development of sports and fitness APPs.Methods ...Objective To study the increasing use of sports and fitness APPs against the background of national fitness and post-epidemic era,and to provide some suggestions for the development of sports and fitness APPs.Methods Literature survey and mathematical statistics were used to define the concept of sports and fitness APPs,and their characteristics and advantages were investigated.Then,their problems were pointed out.Results and Conclusion The existing problems include some APPs favoring female users,single function,and slightly backward profit model.Some countermeasures such as enriching course types,taking into account all categories of users,expanding more functions,improving service quality,broadening profit channels,and improving marketing level are put forward.This can provide theoretical basis for the operation of sports and fitness APPs and better popularize the culture of national fitness.展开更多
Blooms of the toxic dinoflagellate Alexandrium spp.,which produce paralytic shellfish toxins(PSTs),have threatened marine ecosystems for decades.However,their impacts on benthic copepods remain underexplored.Here,we i...Blooms of the toxic dinoflagellate Alexandrium spp.,which produce paralytic shellfish toxins(PSTs),have threatened marine ecosystems for decades.However,their impacts on benthic copepods remain underexplored.Here,we investigated the physiological and biochemical responses of marine benthic copepod Tigriopus japonicus to Alexandrium pacificum.Adult female showed no mortality within 24 h and maintained high survival(>80%)across all A.pacificum concentrations over 96 h,with no significant difference from non-toxic controls.Ingestion rates on A.pacificum and non-toxic controls were similar,when algal prey concentrations were lower than about 2500µgC/L.However,above this threshold,feeding of T.japonicus was significantly depressed by A.pacificum.Six-day exposure induced oxidative stress,marked by elevated level of reactive oxygen species,malondialdehyde,total antioxidant capacity and superoxide dismutase activity,while catalase activity showed a non-significant increase.Moreover,concentration-dependent increase was observed in acetylcholinesterase activity,and its positive correlation with oxidative biomarkers suggests additional roles in coping with stress.Chronic exposure over three generations did not consistently affect development,except for complete development failure in F2 and F3 at the highest concentration.However,moderate-to-high concentrations of A.pacificum significantly impaired reproduction,reducing egg production by 9.66%–96.07%and clutch numbers by 33.33%–55.56%.Our findings indicate that Alexandrium blooms can adversely impact benthic copepod feeding and population recruitment through neurotoxicity and oxidative stress,highlighting the ecological risks of prolonged algal blooms in benthic habitats.展开更多
BACKGROUND The prevalence of metabolic syndrome(MetS)in adolescents is rising,correlating with the global increase in obesity and physical inactivity.AIM To examine the individual and combined associations of fitness,...BACKGROUND The prevalence of metabolic syndrome(MetS)in adolescents is rising,correlating with the global increase in obesity and physical inactivity.AIM To examine the individual and combined associations of fitness,fatness,visceral adiposity index(VAI),and lipid ratios with MetS risk in Nigerian adolescents.METHODS This cross-sectional study included a sample of 403 adolescents(201 girls and 202 boys)aged 11-19 years.Participants were assessed for cardiorespiratory fitness,body mass index(BMI),VAI,triglyceride-to-high-density lipoprotein cholesterol ratio(TG/HDL-C),and total cholesterol-to-high-density lipoprotein cholesterol ratio(TC/HDL-C).Regression models adjusted for age and sexual maturity were used to determine the associations between these health markers and MetS risk.RESULTS Among the 177 high-risk adolescents,56.6%were at risk of central obesity,49.1%had low fitness,33.3%had dyslipidemia,and 11.7%were obese.After controlling for confounding variables,all health markers were independently and jointly associated with MetS risk,with VAI displaying the strongest explanatory power(girls:β=1.308,P<0.001;boys:β=2.300,P<0.001).Unfit girls were 5.1%more likely to be at risk of MetS,while the odds of unfit boys being at risk of MetS is 3.6.Boys with elevated VAI were 22.3 times more likely to be at risk of MetS,while the likelihood of girls with elevated VAI developing MetS risk is 2.78.CONCLUSION Health markers were independently and jointly associated with MetS risk in adolescents,with VAI and dyslip-idemia contributing most significantly.Promoting healthy eating and also aerobic activities among adolescents is crucial for improving metabolic health.展开更多
BACKGROUND Hypertension(HTN)is a significant global health concern due to its rising prevalence and associated risks of cardiovascular disease,chronic kidney disease,and other comorbidities.The increasing rates of HTN...BACKGROUND Hypertension(HTN)is a significant global health concern due to its rising prevalence and associated risks of cardiovascular disease,chronic kidney disease,and other comorbidities.The increasing rates of HTN among youth have been partly attributed to the global rise in childhood obesity,lipid abnormalities,and sedentary lifestyles.AIM To investigate the independent associations of aerobic fitness(AF),the triglyceride-to-high-density lipoprotein cholesterol(TG/HDL-C)ratio,visceral adiposity index(VAI),and resting blood pressure(BP)in Nigerian adolescents.METHODS A multistage sampling technique was used to select 403 in-school adolescents aged 11-19 years in Kogi East,Nigeria.Participants were assessed for AF,TG/HDL-C ratio,VAI,systolic BP(SBP),and diastolic BP(DBP).The associations between the independent variables and the risk of systolic and diastolic HTN were examined using multivariate regression models,controlling for age and maturity status.Receiver operating characteristics curve(ROC)and area under the curve(AUC)were employed to determine the predictive capacities of the independent variables.RESULTS The overall prevalence of systolic HTN was 5.5%(girls:7%;boys:4%)while diastolic HTN was 12.7%(girls:16.9%;boys:8.4%).Among girls,all independent variables showed significant associations with SBP,including fitness(P<0.001),TG/HDL-C(P<0.001),and VAI(P<0.001),with VAI showing the strongest association.In boys,all independent variables except VAI(P=0.063)were significantly associated with SBP,with fitness showing the stronger predictive power(Fitness,P<0.001;TG/HDL-C,P=0.029).For DBP,all independent variables,except fitness in girls(P=0.099),were significantly associated(P<0.001)in both sexes.Unfit boys were 1.1 times more likely to develop systolic HTN(95%CI:1.01–1.15,P=0.018)and had 1.1 times higher odds of developing diastolic HTN(95%CI:1.03–1.13,P=0.001).Only the ROC for DBP turned up significant(P<0.001)AUCs for TG/HDL-C and VAI in girls only,with 0.6 and 1.0 thresholds respectively.CONCLUSION AF,dyslipidemia,and visceral adipose tissue dysfunction were independently associated with the risk of HTN in Nigerian adolescents.These findings highlight the importance of promoting a healthy diet and encouraging aerobic physical activity among adolescents to reduce the risk of HTN.展开更多
Background:Cardiorespiratory fitness(CRF)is a powerful health marker recommended by the American Heart Association as a clinical vital sign.Comparing the predictive validity of objectively measured CRF(the"gold s...Background:Cardiorespiratory fitness(CRF)is a powerful health marker recommended by the American Heart Association as a clinical vital sign.Comparing the predictive validity of objectively measured CRF(the"gold standara")and estimated CRF is clinically relevant because estimated CRF is more feasible.Our objective was to meta-analyze cohort studies to compare the associations of objectively measured,exerciseestimated,and non-exercise-estimated CRF with all-cause and cardiovascular disease(CVD)mortality in adults.Methods:Systematic searches were conducted in 9 databases(MEDLINE,SPORTDiscus,Embase,Scopus,PsycINFO,Web of Science,PubMed,CINAHL,and the Cochrane Library)up to April 11,2024.We included full-text refereed cohort studies published in English that quantified the association(using risk estimates with 95%confidence intervals(95%CIs))of objectively measured,exercise-estimated,and non-exercise-estimated CRF with all-cause and CVD mortality in adults.CRF was expressed as metabolic equivalents(METs)of task.Pooled relative risks(RR)for all-cause and CVD mortality per 1-MET(3.5 mL/kg/min)higher level of CRF were quantified using random-effects models.Results:Forty-two studies representing 35 cohorts and 3,813,484 observations(81%male)(362,771 all-cause and 56,471 CVD deaths)were included.The pooled RRs for all-cause and CVD mortality per higher MET were 0.86(95%CI:0.83-0.88)and 0.84(95%CI:0.80-0.87),respectively.For both all-cause and CVD mortality,there were no statistically significant differences in RR per higher MET between objectively measured(RR range:0.86-0.90)and maximal exercise-estimated(RR range:0.85-0.86),submaximal exercise-estimated(RR range:0.91-0.94),and non-exercise-estimated CRF(RR range:0.81-0.85).Conclusion:Objectively measured and estimated CRF showed similar dose-response associations for all-cause and CVD mortality in adults.Estimated CRF could provide a practical and robust alternative to objectively measured CRF for assessing mortality risk across diverse populations.Our findings underscore the health-related benefits of higher CRF and advocate for its integration into clinical practice to enhance risk stratification.展开更多
The Internet of Things(IoT)technology offers significant advancements in fitness trackers and AI-driven health management systems and presents practical applications for monitoring health and performance.New energy co...The Internet of Things(IoT)technology offers significant advancements in fitness trackers and AI-driven health management systems and presents practical applications for monitoring health and performance.New energy composites,which improve the performance of traditional metals,have been widely used in automotive manufacturing but have limited application in the sports industry.To bridge this gap,the study proposes integrating these advanced composites into sports equipment and facilities,utilizing IoT technology as the foundation for intelligent health monitoring.The research explores how IoT technology can enhance the promotional impact of fitness equipment within the sports industry.Additionally,the communication process for data assessment is conducted using the Priority-based Congestion-avoidance Routing Protocol(PCRP)to ensure efficient data transmission.The analysis of sports activities is performed by utilizing the data transferred through PCRP.Experimental results show that the proposed mechanism outperforms conventional models,achieving an energy efficiency of 0.502 joules(J),a delay of 0.407 seconds(s),and a throughput of 0.620.These results demonstrate the potential of combining IoT technology and new energy composites to revolutionize sports equipment and enhance fitness monitoring systems.These findings highlight the potential of combining IoT and advanced composite materials to revolutionize sports equipment,improve fitness monitoring,and contribute to the growth of the sports industry through enhanced data management and energy-efficient technologies.展开更多
Type 2 diabetes mellitus(T2DM)is increasing among adolescents,but paediatric risk predictors are relatively underdeveloped.This study aimed to establish the associations of visceral adiposity index(VAI)and cardiorespi...Type 2 diabetes mellitus(T2DM)is increasing among adolescents,but paediatric risk predictors are relatively underdeveloped.This study aimed to establish the associations of visceral adiposity index(VAI)and cardiorespiratory fitness(CRF)with fasting plasma glucose in 418 Nigerian adolescents aged 11 years to 19 years.Using a cross-sectional design,participants were stratified by VAI and CRF tertiles to examine variations in impaired fasting glucose(IFG)risk.The findings of this study revealed significant gender differences:In the case of boys,high VAI and low CRF is associated with IFG,while no association was present in girls.CRF,measured by the 20-meter shuttle run,was a stronger predictor of IFG than VAI,suggesting that physical fitness is a protective factor against glucose dysreg-ulation.These findings point to VAI and CRF as useful,non-invasive predictors of risk for T2DM in youth,supporting school-based fitness programs that promote CRF and attenuate visceral adiposity,particularly in males.Future work must validate these predictors across various ethnic populations and identify other risk factors that can augment plans for early interventions aimed at the prevention of adolescent T2DM.展开更多
Objectives:To assess the effects of a wearable-sensorassisted multicomponent exercise program on physical fitness,cognition and quality of life in a practical setting involving frail older adults.Methods:Frail older a...Objectives:To assess the effects of a wearable-sensorassisted multicomponent exercise program on physical fitness,cognition and quality of life in a practical setting involving frail older adults.Methods:Frail older adults(n=130)were randomly divided into a control(CG,n=68)group and an exercise group(EG,n=62)in a 12-week intervention,which included stride gait training with wearable sensors;aerobic exercise;and resistance,flexibility,balance,and cognitive training.Primary outcomes(physical fitness)were evaluated via the SPPB and SFT.Secondary outcomes(cognitive ability,quality of life and frailty)were evaluated via the MoCA-BC,SF-36 and Fried frailty criteria,respectively.Results:After the 12-week intervention,the EG demonstrated significant improvements(p<0.05)vs.the CG in gait speed(β_(3)=0.424,coefficient of interaction effect between group and time from the generalized linear mixed model),chair stand(β_(3)=0.501)and total score(β_(3)=65.466)of SPPB and all SFT components including 6MWT(walked distance,β_(3)=1.098;walking speed,β_(3)=0.105;stride length,β_(3)=0.041),back scratch(β_(3)=4.926),chair sit and reach(β_(3)=3.762),30s arm curl(β_(3)=6.124),30s sit-to-stand(β_(3)=3.04),and TUG(β_(3)=−6.712).The MoCA-BC total,verbal fluency and delayed recall scores;the physical function,general health,vitality,and mental health scores of the SF-36;and the frailty phenotype in the EG were significantly improved compared with those of the CG.Conclusions:The progressive wearable-sensor-assisted multicomponent exercise program designed in this study enhanced physical fitness,cognitive ability and quality of life and slowed down the progression of frailty in frail older adults,supporting its potential as a feasible communitybased health intervention.展开更多
Background:This study evaluated physical fitness and mental health in young and elderly women 3 months after mild COVID-19 infection,and examined the impact of infection and age on long COVID occurrence and trajectory...Background:This study evaluated physical fitness and mental health in young and elderly women 3 months after mild COVID-19 infection,and examined the impact of infection and age on long COVID occurrence and trajectory.Methods:There were 213 eligible female volunteers(107 young,106 elderly)recruited approximately three months after the significant outbreak of COVID-19 in China.Participants completed a fitness test and mental health assessment using the Post-Traumatic Stress Disorder Self-Assessment Scale(PTSD)and the Pittsburgh Sleep Quality Inventory(PSQI).Results:Despite no significant difference in physical fitness,infected young and elderly females experienced poorer sleep quality related to mental health compared to their uninfected peers(+22%in young participants,p=0.027;+10%in elderly participants,p=0.005).The elderly scored significantly higher in sleep quality than the young(p<0.05).Age,previous infection,and PTSD were significant predictors of sleep quality,explaining 60.6%of the variance in PSQI scores.Conclusions:Three months following COVID-19 infection,infected women experienced poorer sleep quality compared to their uninfected peers.Irrespective of being infected,older individuals exhibited higher rates of sleep disorders compared to younger women,suggesting the importance of addressing postCOVID-19 sleep issues among at-risk individuals.展开更多
BACKGROUND Cardiorespiratory fitness(CRF)is inversely associated with the risk of cardiovascular disease,which is related to impaired vascular function.However,its relationship with vascular function remains unknown i...BACKGROUND Cardiorespiratory fitness(CRF)is inversely associated with the risk of cardiovascular disease,which is related to impaired vascular function.However,its relationship with vascular function remains unknown in patients with type 2 diabetes.AIM To assess the relationship of CRF with vascular function in type 2 diabetes.METHODS Patients with type 2 diabetes who were aged≥18 years and underwent an incremental and symptom-limited exercise test were included.Vascular function was assessed by the construction of the vascular health index(VHI),which is defined as a composite score of ankle-brachial index,transcutaneous oxygen pressure,pulse wave velocity,and carotid intima-media thickness.Impaired vascular function is defined as a VHI of<8 points.Linear and logistic regression analyses were used to assess the associations.RESULTS We included 343 patients with type 2 diabetes.CRF was positively correlated with VHI(β=0.10,P=0.047),particularly with ankle-brachial index and pulse wave velocity.The odds ratio(OR)of impaired vascular function was 0.44[95%confidence interval(CI):0.20-0.96]for the highest vs the lowest CRF category.For each one metabolic equivalent increase in CRF,the OR of impaired vascular function was 0.73(95%CI:0.57-0.93).CONCLUSION Higher CRF was associated with better vascular function and lower odds of impaired vascular function in patients with type 2 diabetes.展开更多
Objectives:The objective of this study was to examine communication effectiveness(CE)in conjunction with participant satisfaction in a multicultural fitness program.Methods:Adults from a fitness program site with part...Objectives:The objective of this study was to examine communication effectiveness(CE)in conjunction with participant satisfaction in a multicultural fitness program.Methods:Adults from a fitness program site with participant diversity and multicultural backgrounds were selected and asked to complete a three-part Fitness CE Evaluation Scale questionnaire:CE Questionnaire and Customer Satisfaction(CS)Scale plus a short demographic survey.A sample of 95 participants was recruited from a Midwest Functional 45 Fitness Training Program site in the U.S.A.Multivariate Analysis of Variance(MANOVA)tests were conducted for CE and CS variable vectors.Results:The results showed that there were significant main effects on CE and CS for nationality(p=0.001;p<0.001)and language(p=0.006;p<0.001),but no effect for participation frequency,respectively;there were also significant main effects on CS for gender(p=0.006)and membership type(p=0.019).Univariate tests revealed that domestics and/or first language participants scored significantly higher on reactionto strangers(p=0.001;p=0.001),uncertainty(p<0.001;p<0.001),facilities/services(p<0.001;p<0.001),individual/psychological factor(p=0.009;p=0.034),relaxation(p=0.018;p=0.021),social factor(p<0.001;p=0.002),and health/fitness(p<0.001;p=0.001),respectively.Conclusions:Being highly aware of fitness participants’uncertainty and reaction to strangers can help multicultural fitness program managers or trainers improve their communication effectiveness,which will continue improving their customers’satisfaction.展开更多
At the present paper,adult populations of the psocid, Liposcelis bostrychophila ,were exposed respectively for 30 generations to two atmospheres containing 0 5% and 1% O 2 (N 2 in mixture as balance),in order to...At the present paper,adult populations of the psocid, Liposcelis bostrychophila ,were exposed respectively for 30 generations to two atmospheres containing 0 5% and 1% O 2 (N 2 in mixture as balance),in order to select strains resistant to low O 2 content (LOC) atmosphere.Selection pressure was maintained at around 70% mortality.At the 30th generation,comparison of sensitivity between the selected strains (LOC1 and LOC2) and the original susceptible strain (CA S) indicated a tolerance factor (TF) at the 50% mortality level (LT 50 ) of 4 7 and 3 9 fold,respectively.Throughout the selection process,log time against probit mortality lines remained roughly parallel and the slopes remained lower than that of CA S strain until the last generation.The implication is that at high level of selection,multiple genetic factors continued act together even at the 30th generation to select for adaptation to survival at depleted O 2 concentration.Up to 30th generation,two selected strains still possessed the genetic potential to develop resistance to LOC.Removal of selection pressure for 5 generations from 2 sub populations of two selected strains from 25th generation caused significant reduction in resistance.In the absence of CA exposure,the two selected strains all possessed the reproductive disadvantages or fitness defect.LOC1 and LOC2 were calculated by R 0 to have a fitness value of 0 56 and 0 75 relative to unselected strain,respectively.展开更多
Maize is one of our country quite important grain crops,its height output is an important pillar ensure that grain of our country is safe,if speedy science ascertaining that maize expediency area cultivating,it can pr...Maize is one of our country quite important grain crops,its height output is an important pillar ensure that grain of our country is safe,if speedy science ascertaining that maize expediency area cultivating,it can provide the most reliable decision-making reference to jobs such as agricultural regionalization,crop layout,accurate agriculture of essence.The article carries out a maize cultivating expediency research make use of the minute RS and GIS means,it can guarantee the results is timeliness and scientificalness.展开更多
[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixi...[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixis two pairs of complete linkage gene under difference fitness was built by using difference equations to study elimination mechanism and genetic equilibrium state of panncticcoinplete linkage gene.[Result]The panmixis is different from Hardy-Weinberg Equilibrium which reached the equilibrium just by one generation.A method that by using linear equation to calculate the frequency of four gametes and the fitnessed of panmixis was established after detormining is the fitness of 10 genotypes the necessary and sufficient condition of the panmixis to reach balance.[Conclusion]The method is valuable for reference on linkage disequilibrium and hitchhiking effect study.展开更多
基金funded by the National Institutes of Health and the National Heart,Lung,and Blood Institute(P01HL040962)。
文摘Background:Midlife lifestyle factors,including physical activity,are associated with late-life brain health,yet the role of aerobic exercise on structural brain health in early and mid-adulthood remains poorly understood.This study aimed to examine the effect of aerobic exercise on structural brain age and to explore potential mediators.Methods:In a single-blind,12-month randomized clinical trial,130 healthy participants aged 26-58 years were randomized into a moderate-to-vigorous intensity aerobic exercise group or a usual-care control group.The exercise group attended two supervised 60-min sessions per week in a laboratory setting plus engaged in home-based exercise to achieve 150 min of exercise per week.Brain-predicted age difference(brain-PAD)and cardiorespiratory fitness(CRF)were assessed at baseline and 12 months.Both intention-to-treat(ITT)and completers analyses(including participants who completed post-intervention assessments)were performed.Results:The 130 participants(67.7%female)had an age of 41.28±9.93 years(mean±SD).At baseline,higher CRF(peak oxygen uptake,VO_(2peak))was associated with smaller brain-PAD(β=-0.309,p=0.012).After the intervention,the exercise group showed a decrease in brainPAD(estimated mean difference(EMD)=-0.60;95%confidence interval(95%CI):-1.15 to-0.04;p=0.034)compared to the control group(EMD=0.35;95%CI:-0.21 to 0.92;p=0.217);time×group interaction(between-group difference(BGD)=-0.95;95%CI:-1.72 to-0.17;p=0.019).VO2peak improved in the exercise group(EMD=1.60;95%CI:0.29-2.90;p=0.017)compared to the control group(EMD=-0.78;95%CI:-2.17 to 0.60;p=0.265);time×group interaction(BGD=2.38;95%CI:0.52-4.25;p=0.015).Body composition,blood pressure,and brain-derived neurotrophic factor levels were unaffected.None of the proposed pathways statistically mediated the effect of exercise on brain-PAD.The results from completers were similar.Conclusion:Engaging in 12 months of moderate-to-vigorous exercise reduced brain-PAD in early-to-midlife adults.The pathways by which these effects occur remain unknown.
基金supported by the National Key Research and Development Program of China (Grant No.2022YFC3600403)Emerging Interdisciplinary Platform for Medicine and Engineering in Sports (EIPMES),Beijing,China。
文摘Energy expenditure estimation can be used to measure the exercise load and physical condition of different individuals, such as soldiers, athletes, firemen, etc., during their training and work. Energy expenditure estimation methods based on computer vision have rapidly developed in recent years. Compared with sensor-based methods, such methods are capable of monitoring several target persons at the same time, and the subjects do not need to wear different sensor devices that hamper their movement. In this paper, we propose a cross-attention spatial–temporal convolutional neural network to predict the energy expenditure of people under different exercise intensities. The model explores the relationship between changes in the human skeleton and energy expenditure intensity. In addition, a cross-attention correction module is used to reduce the negative effects of individual physical fitness characteristics during energy expenditure estimation. The experimental results show that our proposed method achieves high accuracy for energy expenditure estimation and performs better than existing computer vision-based energy expenditure estimation methods do. The proposed method can be widely used in various physical activity scenarios to measure energy expenditure, increasing the convenience of usage.
文摘Measuring cardiorespiratory fitness(CRF)is an important predictor of morbidity and mortality in epidemiological studies and clinical settings.1 However,the feasibility of measuring maximal CRF is low due to the time,equipment,and expertise needed to conduct laboratory cardiopulmonary exercise testing(CPET)to determine the maximal rate of oxygen uptake(VO2max)as an objective measure of CRF.Alternatively,indirect estimates of CRF have been applied by measuring maximal duration on treadmill or cycle ergometer tests,2,3 extrapolating maximal CRF from workload or heart rate during submaximal fitness tests,4,5 and using non-exercise algorithms to estimate CRF from an individual’s age,sex,body mass,and physical activity habits.6 It is assumed that objectively measured VO2max is superior to extrapolated and estimated values due to errors associated with the estimated values;7,8 however,until Singh et al.9 newly released article in the Journal of Sport and Health Science,the comparability of these methods in identifying risks for all-cause and cardiovascular disease(CVD)mortality was unknown.
基金supported by the Grant PID2020-120249RB-I00PID2023-148404OB-100funded by MCIN/AEI/10.13039/501100011033+4 种基金by the Andalusian Government(Junta de Andalucía,Plan Andaluz de Investigación,ref.P20_00124)by the Erasmus+Sport Programme of the European Union within the project FitBack4Literacy(No.101089829)Additional support is provided by the University of Granada,Plan Propio de Inves-tigación,Units of ExcellenceUnit of Excellence on Exercise,Nutrition and Health(UCEENS)by theCIBERobn Physiopa-thology of Obesity and Nutrition,and by the Spanish Network in Exercise and Health,EXERNET Network(RED2022-134800-Tand EXP_99828).
文摘Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit international monitoring and surveillance.The objective of the study was to seek international consensus on a proposed,evidence-informed,Youth Fitness International Test(YFIT)battery and protocols for health monitoring and surveillance in children and adolescents aged 618 years.Methods:We conducted an international modified Delphi study to evaluate the level of agreement with a proposed,evidence-based,YFIT of core health-relatedfitness tests and protocols to be used worldwide in 6-to 18-year-olds.This proposal was based on previous European and North American projects that systematically reviewed the existing evidence to identify the most valid,reliable,health-related,safe,and feasiblefitness tests to be used in children and adolescents aged 618 years.We designed a single-panel modified Delphi study and invited 216 experts from all around the world to answer this Delphi survey,of whom one-third are from low-to-middle income countries and one-third are women.Four experts were involved in the piloting of the survey and did not participate in the main Delphi study to avoid bias.We pre-defined an agreement of 80%among the expert participants to achieve consensus.Results:We obtained a high response rate(78%)with a total of 169fitness experts from 50 countries and territories,including 63 women and 61 experts from low-or middle-income countries/territories.Consensus(>85%agreement)was achieved for all proposed tests and protocols,supporting the YFIT battery,which includes weight and height(to compute body mass index as a proxy of body size/composition),the 20-m shuttle run(cardiorespiratoryfitness),handgrip strength,and standing long jump(muscularfitness).Conclusion:This study contributes to standardizingfitness tests and protocols used for research,monitoring,and surveillance across the world,which will allow for future data pooling and the development of international and regional sex-and age-specific reference values,health-related cut-points,and a global picture offitness among children and adolescents.
基金Liaoning Provincial Social Science Planning Fund Office(2019)(L19BGL034).
文摘Objective To study the increasing use of sports and fitness APPs against the background of national fitness and post-epidemic era,and to provide some suggestions for the development of sports and fitness APPs.Methods Literature survey and mathematical statistics were used to define the concept of sports and fitness APPs,and their characteristics and advantages were investigated.Then,their problems were pointed out.Results and Conclusion The existing problems include some APPs favoring female users,single function,and slightly backward profit model.Some countermeasures such as enriching course types,taking into account all categories of users,expanding more functions,improving service quality,broadening profit channels,and improving marketing level are put forward.This can provide theoretical basis for the operation of sports and fitness APPs and better popularize the culture of national fitness.
基金the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.LSKJ202203206)the Fundamental Research Funds for the Central Universities(No.202161069)。
文摘Blooms of the toxic dinoflagellate Alexandrium spp.,which produce paralytic shellfish toxins(PSTs),have threatened marine ecosystems for decades.However,their impacts on benthic copepods remain underexplored.Here,we investigated the physiological and biochemical responses of marine benthic copepod Tigriopus japonicus to Alexandrium pacificum.Adult female showed no mortality within 24 h and maintained high survival(>80%)across all A.pacificum concentrations over 96 h,with no significant difference from non-toxic controls.Ingestion rates on A.pacificum and non-toxic controls were similar,when algal prey concentrations were lower than about 2500µgC/L.However,above this threshold,feeding of T.japonicus was significantly depressed by A.pacificum.Six-day exposure induced oxidative stress,marked by elevated level of reactive oxygen species,malondialdehyde,total antioxidant capacity and superoxide dismutase activity,while catalase activity showed a non-significant increase.Moreover,concentration-dependent increase was observed in acetylcholinesterase activity,and its positive correlation with oxidative biomarkers suggests additional roles in coping with stress.Chronic exposure over three generations did not consistently affect development,except for complete development failure in F2 and F3 at the highest concentration.However,moderate-to-high concentrations of A.pacificum significantly impaired reproduction,reducing egg production by 9.66%–96.07%and clutch numbers by 33.33%–55.56%.Our findings indicate that Alexandrium blooms can adversely impact benthic copepod feeding and population recruitment through neurotoxicity and oxidative stress,highlighting the ecological risks of prolonged algal blooms in benthic habitats.
文摘BACKGROUND The prevalence of metabolic syndrome(MetS)in adolescents is rising,correlating with the global increase in obesity and physical inactivity.AIM To examine the individual and combined associations of fitness,fatness,visceral adiposity index(VAI),and lipid ratios with MetS risk in Nigerian adolescents.METHODS This cross-sectional study included a sample of 403 adolescents(201 girls and 202 boys)aged 11-19 years.Participants were assessed for cardiorespiratory fitness,body mass index(BMI),VAI,triglyceride-to-high-density lipoprotein cholesterol ratio(TG/HDL-C),and total cholesterol-to-high-density lipoprotein cholesterol ratio(TC/HDL-C).Regression models adjusted for age and sexual maturity were used to determine the associations between these health markers and MetS risk.RESULTS Among the 177 high-risk adolescents,56.6%were at risk of central obesity,49.1%had low fitness,33.3%had dyslipidemia,and 11.7%were obese.After controlling for confounding variables,all health markers were independently and jointly associated with MetS risk,with VAI displaying the strongest explanatory power(girls:β=1.308,P<0.001;boys:β=2.300,P<0.001).Unfit girls were 5.1%more likely to be at risk of MetS,while the odds of unfit boys being at risk of MetS is 3.6.Boys with elevated VAI were 22.3 times more likely to be at risk of MetS,while the likelihood of girls with elevated VAI developing MetS risk is 2.78.CONCLUSION Health markers were independently and jointly associated with MetS risk in adolescents,with VAI and dyslip-idemia contributing most significantly.Promoting healthy eating and also aerobic activities among adolescents is crucial for improving metabolic health.
文摘BACKGROUND Hypertension(HTN)is a significant global health concern due to its rising prevalence and associated risks of cardiovascular disease,chronic kidney disease,and other comorbidities.The increasing rates of HTN among youth have been partly attributed to the global rise in childhood obesity,lipid abnormalities,and sedentary lifestyles.AIM To investigate the independent associations of aerobic fitness(AF),the triglyceride-to-high-density lipoprotein cholesterol(TG/HDL-C)ratio,visceral adiposity index(VAI),and resting blood pressure(BP)in Nigerian adolescents.METHODS A multistage sampling technique was used to select 403 in-school adolescents aged 11-19 years in Kogi East,Nigeria.Participants were assessed for AF,TG/HDL-C ratio,VAI,systolic BP(SBP),and diastolic BP(DBP).The associations between the independent variables and the risk of systolic and diastolic HTN were examined using multivariate regression models,controlling for age and maturity status.Receiver operating characteristics curve(ROC)and area under the curve(AUC)were employed to determine the predictive capacities of the independent variables.RESULTS The overall prevalence of systolic HTN was 5.5%(girls:7%;boys:4%)while diastolic HTN was 12.7%(girls:16.9%;boys:8.4%).Among girls,all independent variables showed significant associations with SBP,including fitness(P<0.001),TG/HDL-C(P<0.001),and VAI(P<0.001),with VAI showing the strongest association.In boys,all independent variables except VAI(P=0.063)were significantly associated with SBP,with fitness showing the stronger predictive power(Fitness,P<0.001;TG/HDL-C,P=0.029).For DBP,all independent variables,except fitness in girls(P=0.099),were significantly associated(P<0.001)in both sexes.Unfit boys were 1.1 times more likely to develop systolic HTN(95%CI:1.01–1.15,P=0.018)and had 1.1 times higher odds of developing diastolic HTN(95%CI:1.03–1.13,P=0.001).Only the ROC for DBP turned up significant(P<0.001)AUCs for TG/HDL-C and VAI in girls only,with 0.6 and 1.0 thresholds respectively.CONCLUSION AF,dyslipidemia,and visceral adipose tissue dysfunction were independently associated with the risk of HTN in Nigerian adolescents.These findings highlight the importance of promoting a healthy diet and encouraging aerobic physical activity among adolescents to reduce the risk of HTN.
基金supported by a grant from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie(Grant agreement No.101028929)supported by an Investigator Grant from the Medical Research Future Fund(MRF1193862)supported by an Australian Government Research Training Program Scholarship.
文摘Background:Cardiorespiratory fitness(CRF)is a powerful health marker recommended by the American Heart Association as a clinical vital sign.Comparing the predictive validity of objectively measured CRF(the"gold standara")and estimated CRF is clinically relevant because estimated CRF is more feasible.Our objective was to meta-analyze cohort studies to compare the associations of objectively measured,exerciseestimated,and non-exercise-estimated CRF with all-cause and cardiovascular disease(CVD)mortality in adults.Methods:Systematic searches were conducted in 9 databases(MEDLINE,SPORTDiscus,Embase,Scopus,PsycINFO,Web of Science,PubMed,CINAHL,and the Cochrane Library)up to April 11,2024.We included full-text refereed cohort studies published in English that quantified the association(using risk estimates with 95%confidence intervals(95%CIs))of objectively measured,exercise-estimated,and non-exercise-estimated CRF with all-cause and CVD mortality in adults.CRF was expressed as metabolic equivalents(METs)of task.Pooled relative risks(RR)for all-cause and CVD mortality per 1-MET(3.5 mL/kg/min)higher level of CRF were quantified using random-effects models.Results:Forty-two studies representing 35 cohorts and 3,813,484 observations(81%male)(362,771 all-cause and 56,471 CVD deaths)were included.The pooled RRs for all-cause and CVD mortality per higher MET were 0.86(95%CI:0.83-0.88)and 0.84(95%CI:0.80-0.87),respectively.For both all-cause and CVD mortality,there were no statistically significant differences in RR per higher MET between objectively measured(RR range:0.86-0.90)and maximal exercise-estimated(RR range:0.85-0.86),submaximal exercise-estimated(RR range:0.91-0.94),and non-exercise-estimated CRF(RR range:0.81-0.85).Conclusion:Objectively measured and estimated CRF showed similar dose-response associations for all-cause and CVD mortality in adults.Estimated CRF could provide a practical and robust alternative to objectively measured CRF for assessing mortality risk across diverse populations.Our findings underscore the health-related benefits of higher CRF and advocate for its integration into clinical practice to enhance risk stratification.
基金supported by the Scientific Research and Innovation Team of Xi’an Eurasia University’Urban Sports Intellectualization Research Team’grant number[2021XJTD08]the Shaanxi Province Sports Bureau Research Project’Research on the Integration of the Whole Industry Chain of Sports Industry’grant number[2023317].
文摘The Internet of Things(IoT)technology offers significant advancements in fitness trackers and AI-driven health management systems and presents practical applications for monitoring health and performance.New energy composites,which improve the performance of traditional metals,have been widely used in automotive manufacturing but have limited application in the sports industry.To bridge this gap,the study proposes integrating these advanced composites into sports equipment and facilities,utilizing IoT technology as the foundation for intelligent health monitoring.The research explores how IoT technology can enhance the promotional impact of fitness equipment within the sports industry.Additionally,the communication process for data assessment is conducted using the Priority-based Congestion-avoidance Routing Protocol(PCRP)to ensure efficient data transmission.The analysis of sports activities is performed by utilizing the data transferred through PCRP.Experimental results show that the proposed mechanism outperforms conventional models,achieving an energy efficiency of 0.502 joules(J),a delay of 0.407 seconds(s),and a throughput of 0.620.These results demonstrate the potential of combining IoT technology and new energy composites to revolutionize sports equipment and enhance fitness monitoring systems.These findings highlight the potential of combining IoT and advanced composite materials to revolutionize sports equipment,improve fitness monitoring,and contribute to the growth of the sports industry through enhanced data management and energy-efficient technologies.
文摘Type 2 diabetes mellitus(T2DM)is increasing among adolescents,but paediatric risk predictors are relatively underdeveloped.This study aimed to establish the associations of visceral adiposity index(VAI)and cardiorespiratory fitness(CRF)with fasting plasma glucose in 418 Nigerian adolescents aged 11 years to 19 years.Using a cross-sectional design,participants were stratified by VAI and CRF tertiles to examine variations in impaired fasting glucose(IFG)risk.The findings of this study revealed significant gender differences:In the case of boys,high VAI and low CRF is associated with IFG,while no association was present in girls.CRF,measured by the 20-meter shuttle run,was a stronger predictor of IFG than VAI,suggesting that physical fitness is a protective factor against glucose dysreg-ulation.These findings point to VAI and CRF as useful,non-invasive predictors of risk for T2DM in youth,supporting school-based fitness programs that promote CRF and attenuate visceral adiposity,particularly in males.Future work must validate these predictors across various ethnic populations and identify other risk factors that can augment plans for early interventions aimed at the prevention of adolescent T2DM.
基金supported by the project of Guangzhou Sports Science and Technology Collaborative Innovation Center(No.SL2022B04J00034)National Key Research and Development Program of China(No.2020YFC2002900)。
文摘Objectives:To assess the effects of a wearable-sensorassisted multicomponent exercise program on physical fitness,cognition and quality of life in a practical setting involving frail older adults.Methods:Frail older adults(n=130)were randomly divided into a control(CG,n=68)group and an exercise group(EG,n=62)in a 12-week intervention,which included stride gait training with wearable sensors;aerobic exercise;and resistance,flexibility,balance,and cognitive training.Primary outcomes(physical fitness)were evaluated via the SPPB and SFT.Secondary outcomes(cognitive ability,quality of life and frailty)were evaluated via the MoCA-BC,SF-36 and Fried frailty criteria,respectively.Results:After the 12-week intervention,the EG demonstrated significant improvements(p<0.05)vs.the CG in gait speed(β_(3)=0.424,coefficient of interaction effect between group and time from the generalized linear mixed model),chair stand(β_(3)=0.501)and total score(β_(3)=65.466)of SPPB and all SFT components including 6MWT(walked distance,β_(3)=1.098;walking speed,β_(3)=0.105;stride length,β_(3)=0.041),back scratch(β_(3)=4.926),chair sit and reach(β_(3)=3.762),30s arm curl(β_(3)=6.124),30s sit-to-stand(β_(3)=3.04),and TUG(β_(3)=−6.712).The MoCA-BC total,verbal fluency and delayed recall scores;the physical function,general health,vitality,and mental health scores of the SF-36;and the frailty phenotype in the EG were significantly improved compared with those of the CG.Conclusions:The progressive wearable-sensor-assisted multicomponent exercise program designed in this study enhanced physical fitness,cognitive ability and quality of life and slowed down the progression of frailty in frail older adults,supporting its potential as a feasible communitybased health intervention.
文摘Background:This study evaluated physical fitness and mental health in young and elderly women 3 months after mild COVID-19 infection,and examined the impact of infection and age on long COVID occurrence and trajectory.Methods:There were 213 eligible female volunteers(107 young,106 elderly)recruited approximately three months after the significant outbreak of COVID-19 in China.Participants completed a fitness test and mental health assessment using the Post-Traumatic Stress Disorder Self-Assessment Scale(PTSD)and the Pittsburgh Sleep Quality Inventory(PSQI).Results:Despite no significant difference in physical fitness,infected young and elderly females experienced poorer sleep quality related to mental health compared to their uninfected peers(+22%in young participants,p=0.027;+10%in elderly participants,p=0.005).The elderly scored significantly higher in sleep quality than the young(p<0.05).Age,previous infection,and PTSD were significant predictors of sleep quality,explaining 60.6%of the variance in PSQI scores.Conclusions:Three months following COVID-19 infection,infected women experienced poorer sleep quality compared to their uninfected peers.Irrespective of being infected,older individuals exhibited higher rates of sleep disorders compared to younger women,suggesting the importance of addressing postCOVID-19 sleep issues among at-risk individuals.
基金Supported by the Noncommunicable Chronic Diseases-National Science and Technology Major Project,No.2024ZD0523303the Funding for Pairing Support to Jiangsu High-Level Hospitals-Zhongda Hospital,No.ZDLYG19the Key Research and Development Program in Jiangsu Province,No.BE2022828.
文摘BACKGROUND Cardiorespiratory fitness(CRF)is inversely associated with the risk of cardiovascular disease,which is related to impaired vascular function.However,its relationship with vascular function remains unknown in patients with type 2 diabetes.AIM To assess the relationship of CRF with vascular function in type 2 diabetes.METHODS Patients with type 2 diabetes who were aged≥18 years and underwent an incremental and symptom-limited exercise test were included.Vascular function was assessed by the construction of the vascular health index(VHI),which is defined as a composite score of ankle-brachial index,transcutaneous oxygen pressure,pulse wave velocity,and carotid intima-media thickness.Impaired vascular function is defined as a VHI of<8 points.Linear and logistic regression analyses were used to assess the associations.RESULTS We included 343 patients with type 2 diabetes.CRF was positively correlated with VHI(β=0.10,P=0.047),particularly with ankle-brachial index and pulse wave velocity.The odds ratio(OR)of impaired vascular function was 0.44[95%confidence interval(CI):0.20-0.96]for the highest vs the lowest CRF category.For each one metabolic equivalent increase in CRF,the OR of impaired vascular function was 0.73(95%CI:0.57-0.93).CONCLUSION Higher CRF was associated with better vascular function and lower odds of impaired vascular function in patients with type 2 diabetes.
基金funded by Department of Education of Guangdong Province(NO.2022GXJK239,2024SQXX_025)Guangzhou Sport University(NO.XGQN202410).
文摘Objectives:The objective of this study was to examine communication effectiveness(CE)in conjunction with participant satisfaction in a multicultural fitness program.Methods:Adults from a fitness program site with participant diversity and multicultural backgrounds were selected and asked to complete a three-part Fitness CE Evaluation Scale questionnaire:CE Questionnaire and Customer Satisfaction(CS)Scale plus a short demographic survey.A sample of 95 participants was recruited from a Midwest Functional 45 Fitness Training Program site in the U.S.A.Multivariate Analysis of Variance(MANOVA)tests were conducted for CE and CS variable vectors.Results:The results showed that there were significant main effects on CE and CS for nationality(p=0.001;p<0.001)and language(p=0.006;p<0.001),but no effect for participation frequency,respectively;there were also significant main effects on CS for gender(p=0.006)and membership type(p=0.019).Univariate tests revealed that domestics and/or first language participants scored significantly higher on reactionto strangers(p=0.001;p=0.001),uncertainty(p<0.001;p<0.001),facilities/services(p<0.001;p<0.001),individual/psychological factor(p=0.009;p=0.034),relaxation(p=0.018;p=0.021),social factor(p<0.001;p=0.002),and health/fitness(p<0.001;p=0.001),respectively.Conclusions:Being highly aware of fitness participants’uncertainty and reaction to strangers can help multicultural fitness program managers or trainers improve their communication effectiveness,which will continue improving their customers’satisfaction.
文摘At the present paper,adult populations of the psocid, Liposcelis bostrychophila ,were exposed respectively for 30 generations to two atmospheres containing 0 5% and 1% O 2 (N 2 in mixture as balance),in order to select strains resistant to low O 2 content (LOC) atmosphere.Selection pressure was maintained at around 70% mortality.At the 30th generation,comparison of sensitivity between the selected strains (LOC1 and LOC2) and the original susceptible strain (CA S) indicated a tolerance factor (TF) at the 50% mortality level (LT 50 ) of 4 7 and 3 9 fold,respectively.Throughout the selection process,log time against probit mortality lines remained roughly parallel and the slopes remained lower than that of CA S strain until the last generation.The implication is that at high level of selection,multiple genetic factors continued act together even at the 30th generation to select for adaptation to survival at depleted O 2 concentration.Up to 30th generation,two selected strains still possessed the genetic potential to develop resistance to LOC.Removal of selection pressure for 5 generations from 2 sub populations of two selected strains from 25th generation caused significant reduction in resistance.In the absence of CA exposure,the two selected strains all possessed the reproductive disadvantages or fitness defect.LOC1 and LOC2 were calculated by R 0 to have a fitness value of 0 56 and 0 75 relative to unselected strain,respectively.
文摘Maize is one of our country quite important grain crops,its height output is an important pillar ensure that grain of our country is safe,if speedy science ascertaining that maize expediency area cultivating,it can provide the most reliable decision-making reference to jobs such as agricultural regionalization,crop layout,accurate agriculture of essence.The article carries out a maize cultivating expediency research make use of the minute RS and GIS means,it can guarantee the results is timeliness and scientificalness.
基金Supported by Scientific Research Grant of the Education Department of Guangxi Zhuang Autonomous Region(200807MS065)Elite Support Fund for Universities in Guangxi Zhuang Autonomous Region~~
文摘[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixis two pairs of complete linkage gene under difference fitness was built by using difference equations to study elimination mechanism and genetic equilibrium state of panncticcoinplete linkage gene.[Result]The panmixis is different from Hardy-Weinberg Equilibrium which reached the equilibrium just by one generation.A method that by using linear equation to calculate the frequency of four gametes and the fitnessed of panmixis was established after detormining is the fitness of 10 genotypes the necessary and sufficient condition of the panmixis to reach balance.[Conclusion]The method is valuable for reference on linkage disequilibrium and hitchhiking effect study.
