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Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon boreal forest

Integrative Zoology 2024年第1期19卷 27-36页

作者： Charles J.KREbS Alice J.KENNEY b.Scott GILbERT Rudy bOONSTRA Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewable Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

baseline studies of small rodent populations in undisturbed ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American boreal forest,the red-backed vole Clethrionomys *** voles breed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change being that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numbers,and winter weather,and for 1-year social interactions,to estimate their contribution to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contribute to changes in density,and we measured their relative contributions statistically with multiple *** rate of winter decline in density was related to both food supply and winter *** rate of summer increase was related to summer berry crops and white spruce cone *** measure of predator numbers was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may be an understanding of social interactions at high density.

关键词： boreal forest climate change density dependence population cycles predation winter severity

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Physiological and perceptual responses to sprint interval exercise using arm versus leg cycling ergometry

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Sports Medicine and Health Science 2024年第4期6卷 385-393页

作者： Todd A.Astorino Shealin Pierce Madisen b.Piva Richard S.Metcalfe Niels b.J.Vollaard Department of Kinesiology CSU—San MarcosSan MarcosCAUSA Applied Sports TechnologyExercise and Medicine(A-STEM)Research CenterSwansea UniversitySwanseaUK Faculty of Health Sciences and Sport University of StirlingStirlingUK

Increases in power output and maximal oxygen consumption(V_O2max)occur in response to sprint interval exercise(SIE),but common use of“all-out”intensities presents a barrier for many ***,lower-body SIE is not feasible for all *** compared physiological and perceptual responses to supramaximal,but“nonall-out”SIE between leg and arm cycling ***-four active adults(mean±SD age:[25±7]y;cycling VO_(2)max:[39±7]mL·kg^(-1)·min^(-1))performed incremental exercise using leg(LCE)and arm cycle ergometry(ACE)to determine VO_(2)max and maximal work capacity(Wmax).Subsequently,they performed four 20 s bouts of SIE at 130% Wmax on the LCE or ACE at cadence=120-130 rev/min,with 2 min recovery between *** exchange data,heart rate(HR),blood lactate concentration(bLa),rating of perceived exertion(RPE),and affective valence were *** showed significantly lower(pbsolute mean([1.24±0.31]L·min^(-1) vs.[1.59±0.34]L·min^(-1);d=1.08)and peak VO_(2)([1.79±0.48]L·min^(-1) vs.[2.10±0.44]L·min^(-1);d=0.70)with ACE versus ***,ACE elicited significantly higher(pbLa was significantly higher([7.0±1.7]mM vs.[5.7±1.5]mM,p=0.024,d?0.83)for LCE versus *** was no significant effect of modality on RPE or affective valence(p>0.42),and lowest affective valence recorded(2.0±1.8)was considered“good to fairly good”.Data show that non“all-out”ACE elicits lower absolute but higher relative HR and VO_(2) compared to *** aversive perceptual responses could make this non-all-out modality feasible for inactive adults.

关键词： High intensity interval training Upper body exercise Peak power output Oxygen uptake blood lactate concentration

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Performance and Safety Improvement of Induction Motors based on Testing and Evaluation Standards

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CES Transactions on Electrical Machines and Systems 2024年第3期8卷 310-318页

作者： Nkosinathi S.Khumalo Ntombizotwa P.Memane Udochukwu b.Akuru Department of Electrical Engineering Tshwane University of TechnologyPretoria 0183South Africa

The induction motor,which converts electrical energy into mechanical energy,has been recognized as the cornerstone of *** rotor of an induction motor can be either a squirrel cage rotor or a wound-type rotor,both existing as magnetless ***-phase squirrel cage induction motors are frequently utilized in industrial drives because they are dependable,have high starting torque,are selfstarting and ***-phase induction motors,on the other hand,are commonly used for small loads such as domestic appliances in form of modest fans,pumps and electric power *** South Africa,there have been reports of fires and explosions resulting in live and property loss because of induction motors that have not been thoroughly tested or are incorrectly labelled in terms of ratings,electrical safety and *** goal of this study is targeted at preventing end-user injuries and failures caused by non-compliant induction motors,by evaluating locally manufactured/imported induction motors based on tests and evaluation from standards(IEC and SANS).The study is conducted using experimental procedures at the Explosion Prevention Technology and Rotating Machines(EPT and RM)laboratory,South African bureau of Standards(SAbS),South *** main finding from the study shows differences in the nameplate characteristics of various induction motors which could have detrimental effects such as production and operational downtime in their end-use industries,at later stages.

关键词： Compliance Induction motors International Electro-Technical standards(IEC) Nameplate Experimental tests South African National Standards(SANS)

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Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto Pedro Pinheiro Sergio b.Goncalves Ivo Roupa Paula Simoes Miguel Tavares da Silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait biomechanics

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Soil Contamination With Zoonotic Geohelminths: Emerging Risks in the Philippines

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Infectious Microbes & Diseases 2024年第1期6卷 1-4页

作者： Jan Clyden b.Tenorio Department of Veterinary Paraclinical Sciences College of Veterinary MedicineUniversity of Southern MindanaoKabacanCotabatoPhilippines

Soil-transmitted helminth(STH)infections continue to be the most prevalent of the 20 neglected tropical diseases,affecting nearly a quarter of the world’s population and causing approximately 2.54 million disability-adjusted life years.1,2 Ascaris lumbricoides,Trichuris trichiuria,and multiple species of hookworms(ie,Ancylostoma duodenale,Necator americanus and Ancylostoma ceylanicum)are known to cause significant infections in *** 70%of the infections are reportedly occurring in Asia,where nearly a quarter of the population is infected with at least one STHspecies.3,4 Infections are particularly deleterious among school-and preschool-aged children,women of reproductive age and immunocompromised *** cognitive and motor development,stunting,malnutrition and other potentially life-long sequelae are the known adverse health effects of STH infections in children.5–7 Hence,control and elimination efforts have been directed at addressing the prevalence and burden of infections among at-risk populations.

关键词： soil-transmitted helminths neglected tropical diseases veterinary public health

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Knotting ligands to control metal coordination geometry

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Science China Chemistry 2024年

作者： Fabien b.L.Cougnon Department of Chemistry and Nanoscience Centre University of Jyv?skyl?

Zinc is a metal of particular importance for life [1]. It is the most abundant transition metal in biological systems after iron and contributes both structural and catalytic roles to many cellular processes. The properties of ZnII, unlike those of any other first-row transition metal ions, explain its biological relevance. Due to its filled d-shell orbitals, ZnIIis redox-stable, has a ligand-field energy stabilization of zero and, consequently, no typical coordination number and geometry. Zinc metalloproteins exploit these features to carry a broad range of chemical reactions in mild *** metalloenzymes, unsaturated ZnIIcentres often act as redox-stable Lewis acids. The protein backbone provides a highly preorganized environment around the metal centre and accompanies the changes in coordination geometry occurring as substrate transformation proceeds, thereby modulating the metal reactivity.

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Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution position and strength of the donors

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Science China Chemistry 2024年第5期67卷 1613-1623页

作者： Changfeng Si Dianming Sun Tomas Matulaitis David b.Cordes Alexandra M.Z.Slawin Eli Zysman-Colman Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2GCz bP, 2DPACz bP, 2FbP2GCz and 2FbP2DPACz. We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant(kRISC) of the emitters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(bP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DPACz bP, containing stronger donors than 2GCz bP, exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPACz bP doped in m CP emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4Cz IPN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DPACz bP HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrimers

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The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes

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Journal of Integrative Agriculture 2024年第2期23卷 444-456页

作者： Dian Chen Xiangming Fang Yu Chen Xiaodong Zheng Zhuo Chen Rodney b.W.Smith Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China School of Public Health Georgia State UniversityAtlanta 30303USA School of Economics Zhejiang Gongshang UniversityHangzhou 310018China College of Public Health University of GeorgiaAthens 30602USA Department of Applied Economics University of MinnesotaSaint Paul 55108USA

The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural *** the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition *** China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous *** exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition *** results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of ***,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage *** analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition *** also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor *** findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.

关键词： Rural Minimum Living Standard Guarantee nutrition height-to-age z-scores stunting rural China

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A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health Science 2024年第1期13卷 61-71页

作者： Alex E.Mohr David b.Pyne Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and Exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and Exercise Sciences Liverpool John Moores UniversityLiverpool L33AFUK

background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public *** has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in English were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the Rob 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： Exercise Experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation

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Chemical-assisted MMP reduction on methane-oil systems:Implications for natural gas injection to enhanced oil recovery

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Petroleum 2024年第1期10卷 101-108页

作者： Mohamed Almobarak Matthew b.Myers Colin D.Wood Yongbing Liu Ali Saeedi Quan Xie Discipline of Petroleum Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin UniversityWestern AustraliaAustralia Commonwealth Scientific and Industrial Research Organization Kensington6151Australia Curtin University Oil and Gas Innovation Centre Management Kensington6151Australia State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation No.8 Xindu AvenueXindu DistrictChengdu 610500PR China

***,the main challenge in this process is the high minimum miscibility pressure(MMP)between natural gas and crude oil,which limits its application and recovery factor,especially in hightemperature ***,we present a novel investigation to quantify the effect of chemicalassisted MMP reduction on the oil recovery ***,we measured the interfacial tension(IFT)of the methane-oil system in the presence of chemical or CO_(2) to calculate the MMP reduction at a constant temperature(373K)using the vanishing interfacial tension(VIT)***,we performed three coreflooding experiments to quantify the effect of MMP reduction on the oil recovery factor under different injection *** interfacial tension measurements show that adding a small fraction(1.5 wt%)of the tested surfactant(SOLOTERRA ME-6)achieved 9%of MMP reduction,while adding 20 wt%of CO_(2) to the methane yields 13%of MMP ***,the coreflooding results highlight the significance of achieving miscibility during gas injection,as the ultimate recovery factor increased from 65.5%under immiscible conditions to 77.2%using chemical-assisted methane,and to 79%using gas mixture after achieving near miscible *** results demonstrate the promising potential of the MMP reduction to signifi-cantly increase the oil recovery factor during gas ***,these results will likely expand the application envelop of the miscible gas injection,in addition to the environmental benefits of utilizing the produced gas by re-injection/recycling instead of flaring which contributes to reducing the greenhouse gas emissions.

关键词： Gas injection Enhanced oil recovery Miscibility Coreflooding

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