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Physical and mechanical properties and microstructures of submarine soils in the Yellow Sea 被引量:1
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作者 Zhuangcai Tian Yihua Chang +6 位作者 Sichao Chen Gengchen Wang Yanhong Hu Chuan Guo Lei Jia Lei Song Jianhua Yue 《Deep Underground Science and Engineering》 2024年第2期197-206,共10页
In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical propertie... In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical properties of silt and sand from the Yellow Sea were measured using a direct shear apparatus and their microstructures were observed using a scanning electron microscope.The test results suggest that the shear strength of silt and sand increases linearly with the increase of normal stress.Based on the direct shear test,the scanning electron microscope was used to observe the section surface of sand.It is observed that the section surface becomes rough,with many“V”‐shaped cracks.Many particles appear on the surface of the silt structure and tend to be disintegrated.The X‐ray diffraction experiment reveals that the sand and silt have different compositions.The shear strength of sand is slightly greater than that of silt under high stress,which is related to the shape of soil particles and the mineral composition.These results can be a reference for further study of other soils in the Yellow Sea;meanwhile,they can serve as soil parameters for the stability and durability analyses of offshore infrastructure construction. 展开更多
关键词 direct shear test MICROSCOPE physical properties submarine soil Yellow Sea
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2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities 被引量:9
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作者 Stephen D.Herrmann Erik A.Willis +10 位作者 Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. Jacobs Jr. 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期6-12,共7页
Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was u... Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health guidelines.Methods:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 years.Using a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since 2011.We replaced estimated METs with measured values when possible.Results:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 papers.We added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older adults.We added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major Headings.Conclusion:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health technologies.The new website with the complete lists of PAs and supporting resources is available at https://pacompendium.com. 展开更多
关键词 ADULTS Energy expenditure EXERCISE MET physical Activities
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Physical,mechanical and thermal properties of vacuum sintered HUST-1 lunar regolith simulant
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作者 Wenbin Han Yan Zhou +2 位作者 Lixiong Cai Cheng Zhou Lieyun Ding 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1243-1257,共15页
Establishing a base on the Moon is one of the new goals of human lunar exploration in recent years.Sintered lunar regolith is one of the most potential building materials for lunar bases.The physical,mechanical and th... Establishing a base on the Moon is one of the new goals of human lunar exploration in recent years.Sintered lunar regolith is one of the most potential building materials for lunar bases.The physical,mechanical and thermal properties of sintered lunar regolith are vital performance indices for the structural design of a lunar base and analysis of many critical mechanical and thermal issues.In this study,the HUST-1 lunar regolith simulant(HLRS)was sintered at 1030,1040,1050,1060,1070,and 1080℃.The effect of sintering temperature on the compressive strength was investigated,and the exact value of the optimum vacuum sintering temperature was determined between 1040 and 1060℃.Then,the microstructure and material composition of vacuum sintered HLRS at different temperatures were characterized.It was found that the sintering temperature has no significant effect on the mineral composition in the temperature range of 1030-1080℃.Besides,the heat capacity,thermal conductivity,and coefficient of thermal expansion(CTE)of vacuum sintered HLRS at different temperatures were investigated.Specific heat capacity of sintered samples increases with the increase of test temperature within the temperature range from-75 to 145℃.Besides,the thermal conductivity of the sintered sample is proportional to density.Finally,the two temperatures of 1040 and 1050℃were selected for a more detailed study of mechanical properties.The results showed that compressive strength of sintered sample is much higher than tensile strength.This study reveals the effects of sintering temperature on the physical,mechanical and thermal properties of vacuum sintered HLRS,and these material parameters will provide support for the construction of future lunar bases. 展开更多
关键词 Lunar base Lunar regolith simulant Vacuum sintering physical properties Mechanical properties Thermal properties
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Effect of Fe_(2)O_(3)on the Structure,Physical Properties and Crystallization of CaO-Al_(2)O_(3)-SiO_(2)Glass
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作者 张峰 XIONG Dehua +7 位作者 谢俊 张继红 HAN Jianjun CHEN Dequan WEN Zhongquan FAN Zhenhua CHEN Lina SUN Tengfei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期954-961,共8页
The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching method.The glass network structur... The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching method.The glass network structure,thermal and mechanical properties,and crystallization behavior changes were investigated by nuclear magnetic resonance spectrometer,Fourier-transform infrared spectro-photometer,X-ray diffractometer,differential scanning calorimetry and field emission scanning electron microscope measurements.The change of Q^(n)in glass structures reveals the glass network connectivity decreases due to the increasing content of Fe_(2)O_(3)addition,resulting in the increasing of non-bridging number in glass structure.The glass densities slightly rise from 2.644 to 2.681 g/cm^(3),while Vickers’s hardness increases at first,from 6.469 to 6.901 GPa,then slightly drops to 6.745 GPa,with Fe_(2)O_(3)content increase.There is almost no thermal expansion coefficient change from different Fe_(2)O_(3)content.The glass transmittance in visible range gradually decreases with higher Fe_(2)O_(3)content,resulting from the strong absorption of Fe^(2+)and Fe^(3+)ions.The calculated activation energy from thermal analysis results first decreases from 282.70 to 231.18 kJ/mol,and then increases to 244.02 kJ/mol,with the Fe_(2)O_(3)content increasing from 0.10wt%to 1.30wt%.Meanwhile,the maximum Avrami constant of 2.33 means the CAS glasses exhibit two-dimensional crystallization.All of the CAS glass-ceramics samples contain main crystal phase of anorthite,the microstructure appears lamellar and columnar crystals. 展开更多
关键词 calcium aluminosilicate glass network structure physical properties CRYSTALLIZATION
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Association between physical activity and risk of gastroesophageal reflux disease:A systematic review and meta-analysis 被引量:2
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作者 Chuting Yu Tinglu Wang +7 位作者 Ye Gao Yunfei Jiao Huishan Jiang Yan Bian Wei Wang Han Lin Lei Xin Luowei Wang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期687-698,共12页
Background:Lifestyle plays an important role in preventing and managing gastroesophageal reflux disease(GERD).In response to the conflicting results in previous studies,we performed a systematic review and meta-analys... Background:Lifestyle plays an important role in preventing and managing gastroesophageal reflux disease(GERD).In response to the conflicting results in previous studies,we performed a systematic review and meta-analysis to investigate this association.Methods:Relevant studies published until January 2023 were retrieved from 6 databases,and the prevalence of symptomatic gastroesophageal reflux(GER)or GERD was determined from the original studies.A random effects model was employed to meta-analyze the association by computing the pooled relative risk(RR)with 95%confidence intervals(95%CIs).Furthermore,subgroup and dose-response analyses were performed to explore subgroup differences and the association between cumulative physical activity(PA)time and GERD.Results:This meta-analysis included 33 studies comprising 242,850 participants.A significant negative association was observed between PA and the prevalence of symptomatic GER(RR=0.74,95%CI:0.66-0.83;p<0.01)or GERD(RR=0.80,95%CI:0.76-0.84;p<0.01),suggesting that engaging in PA might confer a protective benefit against GERD.Subgroup analyses consistently indicated the presence of this association across nearly all subgroups,particularly among the older individuals(RR_(<40 years):RR_(≥40 years)=0.85:0.69,p<0.01)and smokers(RR_(smoker):RR_(non-smoker)=0.67:0.82,p=0.03).Furthermore,a dose-response analysis revealed that individuals who engaged in 150 min of PA per week had a 72.09%lower risk of developing GERD.Conclusion:Maintaining high levels of PA decreased the risk of GERD,particularly among older adults and smokers.Meeting the recommended PA level of 150 min per week may significantly decrease the prevalence of GERD. 展开更多
关键词 physical activity Gastroesophageal reflux disease PREVALENCE Systematic review
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Physical-Rheological Properties and Performances of Rejuvenated(Styrene-Butadiene-Styrene)Asphalt with Polymerized-MDI and Aromatic Oil
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作者 Ao Lu Ming Xiong +3 位作者 Chen Chen Liangjiang Li Haibei Tan Xiong Xu 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1633-1646,共14页
Traditional asphalt rejuvenators,like aromatic oil(AO),are known to be effective in improving the low-temperature properties and fatigue performances of aged SBS(styrene-butadiene-styrene)modified asphalt(SBSMA)binder... Traditional asphalt rejuvenators,like aromatic oil(AO),are known to be effective in improving the low-temperature properties and fatigue performances of aged SBS(styrene-butadiene-styrene)modified asphalt(SBSMA)binders and mixtures.However,these rejuvenators inevitably compromise their high-temperature properties and deformation resistances because they dilute asphalt binder but do not fix the damaged structures of aged SBS.In this study,a highly-active chemical called polymerized 4,4-diphenylmethane diisocyanate(PMDI)was used to assist the traditional AO asphalt rejuvenator.The physical and rheological characteristics of rejuvenated SBSMA binders and the moisture-induced damage and rut deformation performances of corresponding mixtures were comparatively evaluated.The results showed that the increasing proportion of AO compromises the hightemperature property and hardness of aged SBSMA binder,and an appropriate amount of PMDI works to compensate such losses;3%rejuvenator at mass ratio of AO:PMDI=70:30 can have a rejuvenated SBSMA binder with a high-temperature performance similar to that of fresh binder,approximately at 71.4°C;the use of AO can help reduce the viscosity of PMDI rejuvenated SBSMA binder for improving its workability;PMDI can help improve the resistance of AO rejuvenated SBSMA binder to deformation,especially at elevated temperatures,through its chemical reactions with aged SBS;moisture induction can enhance the resistance to damage of rejuvenated mixtures containing AO/PMDI or only PMDI;and the rejuvenator with a mass ratio of AO:PMDI=70:30 can lead the rejuvenated mixture to meet the application requirement,with a rut depth of only 2.973 mm,although more PMDI can result in a higher resistance of rejuvenated mixtures to high-temperature deformation. 展开更多
关键词 Aged SBS modified asphalt polymerized 4 4-diphenylmethane diisocyanate aromatic oil physical properties rheological properties mixture performance
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Physical Literacy的本土化:概念厘定、实践反思及应对 被引量:1
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作者 刘艳妮 王辉 +1 位作者 赵犇 熊文 《山东体育学院学报》 北大核心 2024年第2期96-103,共8页
Physical Literacy(简称PL)是身体活动与健康促进领域的重要理念,也是新时代学校体育的开拓点之一。长期以来,学界对PL的认知存在争议或模糊不清,导致其在实践中出现了一定的迟滞和偏差,故对相关认知加以厘定与反思具有重要意义。研究认... Physical Literacy(简称PL)是身体活动与健康促进领域的重要理念,也是新时代学校体育的开拓点之一。长期以来,学界对PL的认知存在争议或模糊不清,导致其在实践中出现了一定的迟滞和偏差,故对相关认知加以厘定与反思具有重要意义。研究认为:(1)从形式逻辑来看,我国学者构建的PL概念在内涵与外延上存在争议或误用。内涵方面,“素养”作为属概念规定了PL的内在特性;“体育素养”的转译窄化了PL的内涵,而译为“身体素养”更能体现PL的身体本源性;作为面向全民的基础生活素养,PL并非核心素养在体育学科的具体化,不宜将其与体育学科核心素养相等同。外延方面,部分PL的外延体系存在偷换“Physical”概念、子素养客体化、子素养相容等问题。(2)在本土实践中,对PL的评价被横向割裂,且纵向衔接不畅;PL的发展情境囿于学校,家庭、社区等校外情境应用不足。针对以上问题,该研究建议未来既要构建横纵贯通的评价体系,也要注意营造多样化的发展情境。 展开更多
关键词 身体素养 体育素养 核心素养 本土化
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Alexa,let's train now!——A systematic review and classification approach to digital and home-based physical training interventions aiming to support healthy cognitive aging 被引量:1
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作者 Fabian Herold Paula Theobald +5 位作者 Thomas Gronwald Navin Kaushal Liye Zou Eling D.de Bruin Louis Bherer Notger GMüller 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期30-46,共17页
Background:There is mounting evidence that regular physical activity is an important prerequisite for healthy cognitive aging.Consequently,the finding that almost one-third of the adult population does not reach the r... Background:There is mounting evidence that regular physical activity is an important prerequisite for healthy cognitive aging.Consequently,the finding that almost one-third of the adult population does not reach the recommended level of regular physical activity calls for further public health actions.In this context,digital and home-based physical training interventions might be a promising alternative to center-based intervention programs.Thus,this systematic review aimed to summarize the current state of the literature on the effects of digital and home-based physical training interventions on adult cognitive performance.Methods:In this pre-registered systematic review(PROSPERO;ID:CRD42022320031),5 electronic databases(PubMed,Web of Science,Psyclnfo,SPORTDiscus,and Cochrane Library)were searched by 2 independent researchers(FH and PT)to identify eligible studies investigating the effects of digital and home-based physical training interventions on cognitive performance in adults.The systematic literature search yielded 8258 records(extra17 records from other sources),of which 27 controlled trials were considered relevant.Two reviewers(FH and PT)independently extracted data and assessed the risk of bias using a modified version of the Tool for the assEssment of Study qualiTy and reporting in EXercise(TESTEX scale).Results:Of the 27 reviewed studies,15 reported positive effects on cognitive and motor-cognitive outcomes(i.e.,performance improvements in measures of executive functions,working memory,and choice stepping reaction test),and a considerable heterogeneity concerning study-related,population-related,and intervention-related characteristics was noticed.A more detailed analysis suggests that,in particular,interventions using online classes and technology-based exercise devices(i.e.,step-based exergames)can improve cognitive performance in healthy older adults.Approximately one-half of the reviewed studies were rated as having a high risk of bias with respect to completion adherence(≤85%)and monitoring of the level of regular physical activity in the control group.Conclusion:The current state of evidence concerning the effectiveness of digital and home-based physical training interventions is mixed overall,though there is limited evidence that specific types of digital and home-based physical training interventions(e.g.,online classes and step-based exergames)can be an effective strategy for improving cognitive performance in older adults.However,due to the limited number of available studies,future high-quality studies are needed to buttress this assumption empirically and to allow for more solid and nuanced conclusions. 展开更多
关键词 Brain COGNITION Digital health Exercise-cognition physical activity
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Association of accelerometer-measured sleep duration and different intensities of physical activity with incident type 2 diabetes in a population-based cohort study 被引量:2
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作者 Xinyi Jin Yilin Chen +8 位作者 Hongliang Feng Mingqing Zhou Joey W.Y.Chang Yaping Liu Alice Pik Shan Kong Xiao Tan Yun-Kwok Wing Yannis Yan Liang Jihui Zhang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期222-232,共11页
Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a populat... Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a population-based prospective cohort study.Methods:Altogether,88,000 participants(mean age=62.2±7.9 years,mean±SD)were included from the UK Biobank.Sleep duration(short:<6 h/day;normal:6-8 h/day;long:>8 h/day)and PA of different intensities were measured using a wrist-won accelerometer over a 7-day period between 2013 and 2015.PA was classified according to the median or World Health Organization-recommendation:total volume of PA(high,low),moderate-to-vigorous PA(MVPA)(recommended,not recommended),and light-intensity PA(high,low).Incidence of type 2diabetes was ascertained using hospital records or death registries.Results:During a median follow-up of 7.0 years,1615 incident type 2 diabetes cases were documented.Compared with normal sleep duration,short(hazard ratio(HR)=1.21,95%confidence interval(95%CI):1.03-1.41)but not long sleep duration(HR=1.01,95%CI:0.89-1.15)was associated with excessive type 2 diabetes risk.This increased risk among short sleepers seems to be protected against by PA.Compared with normal sleepers with high or recommended PA,short sleepers with low volume of PA(HR=1.81,95%CI:1.46-2.25),not recommended(below the World Health Organization-recommended level of)MVPA(HR=1.92,95%CI:1.55-2.36),or low light-intensity PA(HR=1.49,95%CI:1.13-1.90)had a higher risk of type 2 diabetes,while short sleepers with a high volume of PA(HR=1.14,95%CI:0.88-1.49),recommended MVPA(HR=1.02,95%CI:0.71-1.48),or high light-intensity PA(HR=1.14,95%CI:0.92-1.41)did not.Conclusion:Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes.A higher level of PA,regardless of intensity,potentially ameliorates this excessive risk. 展开更多
关键词 Light physical activity Sleep duration Triaxial accelerometer Type 2 diabetes UK Biobank
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Association of physical activity with risk of chronic kidney disease in China:A population-based cohort study 被引量:1
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作者 Kexiang Shi Yunqing Zhu +12 位作者 Jun Lv Dianjianyi Sun Pei Pei Huaidong Du Yiping Chen Ling Yang Bing Han Rebecca Stevens Junshi Chen Zhengming Chen Liming Li Canqing Yu China Kadoorie Biobank collaborative group 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期204-211,共8页
Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is limited.We aimed to explore the associations of total,domain-specific,and intensity-specific PA with... Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is limited.We aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in China.Methods:The study included 475,376 adults from the China Kadoorie Biobank aged 30-79 years during 2004-2008 at baseline.An interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on quartiles.Cox regression was used to analyze the association between PA and CKD risk.Results:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)cases.Total PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest quartile.Similar results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN risk.Increased nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,respectively.Conclusion:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent. 展开更多
关键词 Chronic kidney disease DOMAIN INTENSITY physical activity
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Key Physical Factors Affecting Spatial-temporal Variation of Labile Organic Carbon Fractions by Biochar Driven in Mollisols Region of Northeast China
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作者 Zhao Wei Liang Fangyuan +4 位作者 Liang Ying Zhao Hongrui Hao Shuai Wang Hongyan Wang Daqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期28-41,共14页
Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between phy... Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between physical properties and LOC fractions. A field positioning experiment was performed in Mollisols region of Northeast China to evaluate the influence of maize stalk biochar on the spatial distribution and temporal changes of physical properties and LOC fractions. Maize stalk biochar treatments included C1(1.5 kg·hm^(-2)), C2(3 kg·hm^(-2)), C3(15 kg·hm^(-2)), C4(30 kg·hm^(-2)), and CK(0). The results showed that maize stalk biochar increased soil water contents(SWC) and soil porosity(SP), but reduced bulk density(BD). Maize stalk biochar reduced dissolved organic carbon(DOC) contents in the 0-20 cm soil layer, ranging from 0.25 g·kg^(-1) to 0.31 g·kg^(-1) in harvest period, while increased in the 20-40 cm soil layer. In addition, the application of biochar had a significant impact on the spatial distribution and temporal change of SWC, BD, SP, DOC, hot-water extractable carbon(HWC), acid hydrolyzed organic carbon(AHC Ⅰ, Ⅱ), and readily oxidized organic carbon(ROC). High amounts of maize stalk biochar up-regulated the contents of soil organic carbon SOC, HWC, AHC Ⅰ, AHC Ⅱ, and ROC. In addition, SWC and SP were the key physical factors to affect LOC fractions. In conclusions, maize stalk biochar could improve physical properties, and then influence LOC fractions, and maize stalk biochar could be used as an organic amendment for restoring degraded soils governed by their rates of addition. 展开更多
关键词 maize stalk biochar labile organic carbon fraction Mollisols region soil physical property dissolved organic carbon
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The association of diet quality and physical activity with cardiovascular disease and mortality in 85,545 older Australians:A longitudinal study 被引量:1
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作者 Ding Ding Joe Van Buskirk +6 位作者 Stephanie Partridge Philip Clare Edward Giovannucci Adrian Bauman Nicole Freene Robyn Gallagher Binh Nguyen 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期841-850,共10页
Background:A quality diet and an active lifestyle are both important cornerstones of cardiovascular disease(CVD)prevention.However,despite their interlinked effects on metabolic health,the 2 behaviors are rarely consi... Background:A quality diet and an active lifestyle are both important cornerstones of cardiovascular disease(CVD)prevention.However,despite their interlinked effects on metabolic health,the 2 behaviors are rarely considered jointly,particularly within the context of CVD prevention.We examined the independent,interactive,and joint associations of diet and physical activity with CVD hospitalization,CVD mortality,and all-cause mortality.Methods:CVD-free Australian participants aged 4574 years(n=85,545)reported physical activity,diet,sociodemographic,and lifestyle characteristics at baseline(20062009)and follow-up(20122015),and data were linked to hospitalization and death registries(03/31/2019 for CVD hospitalization and all-cause mortality and 12/08/2017 for CVD mortality).Diet quality was categorized as low,medium,and high based on meeting dietary recommendations.Physical activity was operationalized as(a)total moderate-to-vigorous physical activity(MVPA)as per guidelines,and(b)the composition of MVPA as the ratio of vigorous-intensity physical activity(VPA)to total MVPA.We used a left-truncated cause-specific Cox proportional hazards model using time-varying covariates.Results:During a median of 10.7 years of follow-up,6576 participants were admitted to the hospital for CVD and 6581 died from all causes(876 from CVD during 9.3 years).A high-quality diet was associated with a 17%lower risk of all-cause mortality than a low-quality diet,and the highest MVPA category(compared with the lowest)was associated with a 44%and 48%lower risk of CVD and all-cause mortality,respectively.Multiplicative interactions between diet and physical activity were non-significant.For all outcomes,the lowest risk combinations involved a high-quality diet and the highest MVPA categories.Accounting for total MVPA,some VPA was associated with further risk reduction of CVD hospitalization and all-cause mortality.Conclusion:For CVD prevention and longevity,one should adhere to both a healthy diet and an active lifestyle and incorporate some VPA when possible. 展开更多
关键词 DIET physical activity Cardiovascular disease MORTALITY Cohort studies
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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults 被引量:1
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao Lin Yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS Body fat distribution physical activity Sitting time
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Bridging the gap:Unveiling the crisis of physical inactivity in inflammatory bowel diseases 被引量:2
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作者 Remus Stafie Ana-Maria Singeap +2 位作者 Adrian Rotaru Carol Stanciu Anca Trifan 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1261-1265,共5页
In this editorial we comment on the article titled“Inflammatory bowel diseases patients suffer from significant low levels and barriers to physical activity:The BE-FIT-IBD study”published in a recent issue of the Wo... In this editorial we comment on the article titled“Inflammatory bowel diseases patients suffer from significant low levels and barriers to physical activity:The BE-FIT-IBD study”published in a recent issue of the World Journal of Gastroen-terology 2023;29(41):5668-5682.Inflammatory bowel diseases(IBD)are emerging as a significant global health concern as their incidence continues to rise on a global scale,with detrimental impacts on quality of life.While many advances have been made regarding the management of the disease,physical inactivity in these patients represents an underexplored issue that may hold the key for further and better understanding the ramifications of IBD.Chronic pain,fatigue,and fear of exacerbating symptoms promotes physical inactivity among IBD patients,while the lack of clear guidelines on safe exercise regimens contributes to a norm of physical inactivity.Physical activity(PA)is accepted to have a positive effect on disease outcomes and quality of life,while inactivity exacerbates comorbidities like cardiovascular disease and mental health disorders.The“BE-FIT-IBD”study,focusing on PA levels and barriers in IBD patients of Southern Italy,revealed that a significant proportion(42.9%)were physically inactive.This lack of PA is attributed to barriers such as fear of flare-ups and misconceptions about exercise exacerbating the disease.The study also highlighted the need for better communication between healthcare providers and patients regarding the benefits of PA and safe incorporation into lifestyles.Moreover,physical inactivity may also contribute to disability in IBD patients,having a great impact on employment status.Of note is the fact that IBD also comes with an important psychological burden with relevant evidence suggesting that regular PA can improve mood,reduce anxiety,and enhance mental health.The“BE-FIT-IBD”study advocated for the integration of PA into IBD management,emphasizing the bidirectional link between PA and IBD.Regular exercise can influence the course of IBD,potentially reducing symptom severity and prolonging remission periods.As such,it is mandatory that healthcare providers actively educate patients,dispel misconceptions,and tailor exercise recommendations to improve the quality of life and reduce IBD-related complications. 展开更多
关键词 Inflammatory bowel disease physical activity DISABILITY Psychological burden Body composition Quality of life
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Interaction between inflammatory bowel disease,physical activity,and myokines:Assessment of serum irisin levels 被引量:1
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作者 Marwan SM Al-Nimer 《World Journal of Gastroenterology》 SCIE CAS 2024年第22期2923-2926,共4页
Inflammatory bowel disease(IBD),including Crohn’s disease and ulcerative colitis,showed a wide spectrum of intestinal and extra-intestinal manifestations,which rendered the patients physically inactive and impaired t... Inflammatory bowel disease(IBD),including Crohn’s disease and ulcerative colitis,showed a wide spectrum of intestinal and extra-intestinal manifestations,which rendered the patients physically inactive and impaired their quality of life.It has been found that physical activity is a non-pharmacological intervention that improves the quality of life for those patients.Irisin is one member of the myokines secreted by muscle contraction during exercise and could be used as an antiinflammatory biomarker in assessing the physical activity of IBD patients.In addition,experimental studies showed that exogenous irisin significantly decreased the inflammatory markers and the histological changes of the intestinal mucosa observed in experimental colitis.Furthermore,irisin produces changes in the diversity of the microbiota.Therefore,endogenous or exogenous irisin,via its anti-inflammatory effects,will improve the health of IBD patients and will limit the barriers to physical activity in patients with IBD. 展开更多
关键词 Irisin Inflammatory bowel disease physical activity MYOKINES Prognostic marker
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Physical Layer Encryption of OFDM-PON Based on Quantum Noise Stream Cipher with Polar Code 被引量:1
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作者 Xu Yinbo Gao Mingyi +3 位作者 Zhu Huaqing Chen Bowen Xiang Lian Shen Gangxiang 《China Communications》 SCIE CSCD 2024年第3期174-188,共15页
Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast e... Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security. 展开更多
关键词 physical layer encryption polar code quantum noise stream cipher
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Shifting the Paradigm:A Fresh Look at Physical Activity Frequency and Its Impact on Mental Health,Life Satisfaction,and Self-Rated Health in Adolescents 被引量:1
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作者 Wenjie Li Yucheng Gao +3 位作者 Guoqing Liu Rongkai Hao Meijie Zhang Xiaotian Li 《International Journal of Mental Health Promotion》 2024年第2期83-92,共10页
As adolescent mental health problems are becoming a more serious issue globally,this paper explores the relationship of physical activity in adolescents and its frequency on mental health as well as examines the media... As adolescent mental health problems are becoming a more serious issue globally,this paper explores the relationship of physical activity in adolescents and its frequency on mental health as well as examines the mediating effects of life satisfaction and self-rated health in order to provide a reference for the promotion of mental health in adolescents.A sample of 3578 Chinese high school students completed questionnaires assessing their mental health,physical activity frequency,life satisfaction,and self-rated health.The mean SCL-90 value for adolescents was found to be 1.629%,and 24.73%of adolescents had varying degrees of mental health issue.Increased physical activity frequency is positively associated with improved mental health(p<0.001).Additionally,life satisfaction and self-rated health were found to play significant mediating roles in the relationship between physical activity frequency and mental health.Specifically,low-frequency physical activity had the most pronounced mediating effect on mental health through life satisfaction,while high-frequency physical activity exerted the most significant mediating effect on mental health through self-rated health.These findings underscore the importance of promoting physical activity among adolescents and highlight the distinct pathways through which physical activity frequency can influence mental health outcomes.Further research is needed to explore these relationships in diverse populations and settings,as well as to develop targeted intervention. 展开更多
关键词 Adolescents physical activity mental health life satisfaction self-rated health
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Physical and Chemical Properties of Horns Sheaths Particles for the Manufacture of Composite Materials
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作者 Tawe Laynde Zakari Yaou +2 位作者 Karga Tapsia Lionel Konai Noel Danwe Raidandi 《Journal of Materials Science and Chemical Engineering》 2024年第5期1-9,共9页
Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated betwe... Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated between 0.586 g/cm<sup>3</sup> and 0.732 g/cm<sup>3</sup>, the swelling rate (12%), and one chemical characterization that permitted us to determine the rate of dry matters (97.05%), of mineral matters (2.5%), of protein matters (94.52%). From these weak values, it can easily be seen that cow horn case doesn’t absorb much water and improve the mechanical characteristics of the composite;the high rate of protein shows that keratin which is the structural molecule favors its gripping as reinforcing element in the manufacturing of composite materials. 展开更多
关键词 HORNS Fibers Polymer Loads physical Properties Chemical Composition
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“Active Feedback” Fitbit-Based Physical Activity and Sleep Hygiene Intervention for Memory Assessment Service (MAS) Patients with Cognitive Deficits: Feasibility, Acceptability, Sleep Quality, Stress, and Wellbeing Outcomes
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作者 Chris Griffiths Farah Hina +6 位作者 Chee Siang Ang Louise Birkett-Swan Casey Bonham Lauren Currell Emily Ward Natasha Stace-Wood Jessica Plumbridge 《Advances in Aging Research》 CAS 2024年第4期61-74,共14页
Research Background: Compared to the general population, people experiencing age-related cognitive decline are more likely to have low levels of physical activity and sleep problems. Sufficient physical activity and q... Research Background: Compared to the general population, people experiencing age-related cognitive decline are more likely to have low levels of physical activity and sleep problems. Sufficient physical activity and quality sleep are protective factors against cognitive decline and poor health and can improve coping with stressors. The “Active Feedback” intervention comprises a wearable activity and sleep tracker (Fitbit), access to Fitbit software healthy lifestyle software apps;one session with Memory Assessment Service (MAS) staff providing physical activity and sleep hygiene advice and two further engagement, discussion, and feedback sessions. Purpose/Aim: This study investigates the acceptability and feasibility of Active Feedback and the effect on stress, mental wellbeing, and sleep quality, and the links between these factors. Methods: An open-label patient cohort design with no control group was used. Pre-intervention, 4-week and 8-week intervention assessments were performed using participant self-report measures: Perceived Stress Scale (PSS), Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS), and Sleep Conditioning Index (SCI). Twenty-five participants completed an eight-week three-session intervention (18 males and 7 females), with the age range of 66 - 84 years old, and average age of 73.8 years (SD = 5.09). Fifteen participants had a diagnosis of MCI, ten participants did not. Results: There were non-significant improvements in SCI scores from 21.0 (SD = 8.84) to 21.6 (SD = 6.20) at 8 weeks, PSS scores from 17.5 (SD = 5.89) to 17.0 (SD = 6.20) at 8 weeks, and WEMWBS scores from 46.9 (SD = 9.23) to 48.8 (SD = 9.69) at 8 weeks. There were negative correlations between WEMWBS and PSS. Conclusion: Active Feedback intervention was found to be feasible and acceptable. Active Feedback could be enhanced to include motivational interviewing and goal setting. 展开更多
关键词 Fitbit TRACKER MCI Exercise INSOMNIA physical Activity Wearables SLEEP
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The Economics of Competing Water Uses under a FERC Licensing Agreement: Estimation of Property Value, Recreation, and Hydroelectric Impacts
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作者 Matthew Bingham Jason Kinnell 《Journal of Water Resource and Protection》 CAS 2024年第6期414-428,共15页
Reservoirs provide a variety of services with economic values across multiple sectors. As demands for reservoir services continue to grow and precipitation patterns evolve, it becomes ever more important to consider t... Reservoirs provide a variety of services with economic values across multiple sectors. As demands for reservoir services continue to grow and precipitation patterns evolve, it becomes ever more important to consider the integrated suite of values and tradeoffs that attend changes in water uses and availability. Section 316 (b) of the Clean Water Act requires that owners of certain water cooled power plants evaluate technologies and operational measures that can reduce their impacts to aquatic organisms. The studies must discuss the social costs and benefits of alternative technologies including cooling towers (79 Fed. Reg. 158, 48300 - 48439). Cooling towers achieve their effect through evaporation. This manuscript estimates the property value, recreation, and hydroelectric generation impacts that could result from the evaporative water loss associated with installing cooling towers at the McGuire Nuclear Generating Station (McGuire) located on Lake Norman, North Carolina. Although this study specifically evaluates the effects of evaporative water loss from cooling towers, its methods are applicable to estimating the economic benefits and costs of a new water user or reduced water input in any complex reservoir system that supports steam electric generation, hydroelectric generation, residential properties, recreation, irrigation, and municipal water use. 展开更多
关键词 property Value FERC Hydroelectric RECREATION Water Levels
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