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How competitive is the‘pioneer-climax’tree species Nothofagus alpina in pristine temperate forests of Chile?

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Journal of Plant Ecology 2019年第1期12卷 144-156页

作者： Rebekka Bögelein Cecilia APérez Philipp Schäferand Frank m.thomas Faculty of Regional and Environmental Sciences GeobotanyUniversity of TrierBehringstraße 2154296 TrierGermany Present address:Thünen-Institut Institut für WaldökosystemeAlfred-Möller-Straße 116225 EberswaldeGermany Departamento de Ecología de Ecosistemas Instituto de Ecología y Biodiversidad(IEB)Alameda 340SantiagoChile

Aims Nothofagus species are constitutive elements of the temperate forests along the Southern Andes *** deciduous Nothofagus alpina is a fast-growing,but long-lived opportunistic pioneer spe-cies(‘pioneer-climax species’)and co-occurs with the evergreen *** tested whether *** is competitively superior to *** in mature stands and whether intra-specific competition in *** is stronger than inter-specific competition with *** In a pristine old-growth forest in South-Central Chile,we compared the growth of *** trees in pure stands and in mixture with *** to the growth of *** and calculated compe-tition *** related growth variables to climate data and weather *** Findings In ***,juvenile basal area increment was signifi-cantly higher in pure than in mixed *** to our hypothesis,*** exhibited larger radial stem increments than *** in the most recent 40 *** the most recent two decades,this was caused by high growth rates of large *** *** both Nothofagus species,stem growth was negatively related to temperature,but *** responded more sensitively to weather conditions than *** ***,stem increment was negatively related to the intensity of competition,but the size of the competition effects on this species was similar in pure and mixed ***,compared to ***,the‘pioneer-climax species’concept is even more appropriate for *** with its relatively high growth rates even in the early stages of its life.

关键词： competition index dendroecology growth-competition relationship pointer year productivity tree-ring analysis

Effect of stress-dependent microannulus aperture on well leakage

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Journal of Rock mechanics and Geotechnical Engineering 2024年第6期16卷 1967-1976页

作者： meng meng Luke P.Frash J.william Carey mohamed mehana Wenfeng Li Bailian Chen Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNMUSA

Debonding at the cement-casing interface is recognized as a principal failure mechanism leading to CO_(2) leakage in *** detachment gives rise to a microannulus,which notably possesses greater permeability than undamaged cement,undermining its sealing ***,the permeability of the microannulus is regarded as a uniform value throughout the ***,fundamentally,a microannulus is one type of fracture,and its gap or aperture size is affected by the effective *** this work,we developed a unique experimental *** equipment facilitates the curing of cement inside a steel casing,the formation of a microannulus between the casing and the cement,and the investigation of the fluid flow dynamics along the microannulus under laboratory-replicated in situ *** microannulus was formed by injecting fluid from one end of the setup,and receiving similar amount of fluid on the other end signified the development of the leakage ***,strain gauges affixed to the casing’s external surface yielded key information on the microannulus’s opening and *** observed a noticeable decline in microannulus hydraulic aperture(or permeability)in relation to effective stress and an exponential equation fits their *** findings also indicate a distinct behavior when comparing liquid CO_(2) with ***,it is easier for liquid CO_(2) to create the ***,the hydraulic aperture range for this microannulus(0.7-6 mm)is considerably smaller than that created by water flow(2-17 mm).Finally,we integrated the stressdependent microannulus aperture size into the combined analysis of well mechanical integrity and well *** outcomes consistently demonstrated that when factoring in the stress-dependent aperture sizes,the leakage rates are 3e5 times compared to a fixed aperture *** traditional assumption of a constant aperture significantly underestimates fluid leakage risks.

关键词： microannulus Leakage assessment Aperture size Triaxial experiment Carbon sequestration

Storylines of family medicine Ⅺ:professional identity formation—nurturing one’s own story

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Family medicine and Community Health 2024年第S03期12卷 99-108页

作者： william B Ventres Leslie A Stone Hamish J Wilson Sumi m Sexton David J Doukas Jessica P Cerdena David m Kelley michael D Fetters Jeffrey J Haney John J Frey III Family and Preventive medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA General Practice and Rural Health University of Otago Dunedin School of MedicineDunedinNew Zealand Family medicine Georgetown University School of MedicineWashingtonDistrict of ColumbiaUSA Family and Community medicine Tulane University School of MedicineNew OrleansLouisianaUSA Family medicine Residency Program Middlesex HealthMiddletownConnecticutUSA Family medicine University of Michigan Medical SchoolAnn ArborMichiganUSA medical Education and Clinical Sciences Washington State UniversitySpokaneWashingtonUSA Family medicine and Community Health University of Wisconsin-Madison School of Medicine and Public HealthMadisonWisconsinUSA

Storylines of Family medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅺ:professional identity formation—nurturing one’s own story’,authors address the following themes:‘The social construction of professional identity’,‘On becoming a family physician’,‘What’s on the test?—professionalism for family physicians’,‘The ugly doc-ling’,‘Teachers—the essence of who we are’,‘Family medicine research—it starts in the clinic’,‘Socially accountability in medical education’,‘Personal philosophy and how to find it’and‘Teaching and learning with Storylines of Family medicine’.may these essays encourage readers to find their own creative spark in medicine.

关键词： own becoming professional

Joint Contact Forces with Changes in Running Stride Length and midsole Stiffness

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Journal of Science in Sport and Exercise 2020年第1期2卷 69-76页

作者： Joshua m.thomas WBrent Edwards Timothy R.Derrick Department of Health Wellnessand SportUniversity of DubuqueDubuqueIA 52001USA Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Kinesiology Iowa State University111L Forker BuildingAmesIA 50011USA

The purpose of this study was to determine if lower extremity joint loading was influenced by stride length or shoe midsole *** subjects completed 10 trials of overground running at an average speed of 4.43 m/s in each of three condi-tions:normal running,running with a stride length(SL)reduced by 10%of normal,and running with a cushioned midsole stiffness(i.e.,mechanical impact reduction of 13.7-10.9 g).Reaction forces calculated from inverse dynamics were summed with muscle forces estimated from a musculoskeletal model using static optimization to obtain joint contact forces at the hip,knee and ankle *** components of the contact forces[axial,anterior-posterior,and medial-lateral(mL)]were examined using parametric statistics(α=0.05).Reducing stride length resulted in significant decreases in absolute peak ankle contact forces in the axial direction(normal:-14.5±1.5 BW;reduced SL:-14.0±1.6 BW)and the mL direction(normal:0.67±0.23 BW;reduced SL:0.61±0.21 BW).Reducing stride length also reduced the peak absolute axial forces at the knee(normal:-10.6±1.3 BW;reduced SL:-9.8±1.2 BW)and the hip(normal:-7.26±2.24 BW;reduced SL:-6.75±2.10 BW).The cushioned shoe did not statistically reduce the peak absolute contact forces from the normal stride condition at any of the *** hoc stress analysis suggested that the observed changes in anterior hip force would increase stress more than any of the other statistically significant *** in stride length appear to decrease some joint contact variables but cushioning in the heel region of the shoe does not.

关键词： Gait Injury Compressive force Shear force Cushioning Strain

Storylines of family medicine Ⅳ:perspectives on practice—lenses of appreciation

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Family medicine and Community Health 2024年第S3期12卷 33-42页

作者： william B Ventres Leslie A Stone Radeeb Akhtar Jeffrey m Ring Lucy m Candib Erick messias Ronald m Epstein marc Tunzi Amy L Lee Christopher P morley Carina m Brown David Slawson Jill Konkin David G Campbell Ian Couper Susan williams Robert Brooks Lucie Walters Family and Preventive medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA Family medicine and Community Health Icahn School of Medicine at Mount SinaiNew YorkNew YorkUSA Independent Health Psychologist Los AngelesCaliforniaUSA Family medicine and Community Health UMass Chan Medical SchoolWorcesterMassachusettsUSA Psychiatry and Behavioral Neurosciences Saint Louis University School of MedicineSaint LouisMissouriUSA Family medicine University of Rochester Medical CenterRochesterNew YorkUSA Family medicine Residency Program Natividad Medical CenterSalinasCaliforniaUSA Family medicine Tufts University School of MedicineBostonMassachusettsUSA Public Health and Preventive medicine SUNY Upstate Medical UniversitySyracuseNew YorkUSA Cone Health Family medicine Residency The University of North Carolina School of MedicineGreensboroNorth CarolinaUSA Family medicine Atrium HealthCharlotteNorth CarolinaUSA Family medicine University of Alberta Faculty of Medicine&DentistryEdmontonAlbertaCanada Cunninghame Arm medical Centre Australian College of Rural and Remote MedicineLakes EntranceQueenslandAustralia Ukwanda Centre for Rural Health Stellenbosch University Faculty of Medicine and Health SciencesCape TownWestern CapeSouth Africa Adelaide Rural Clinical School The University of AdelaideAdelaideSouth AustraliaAustralia Department of Rural Health Broken Hill UniversityBroken HillNew South WalesAustralia Adelaide Rural Clinical School The University of Adelaide Faculty of Health and Medical SciencesMount GambierSouth AustraliaAustralia

Storylines of Family medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅳ:perspectives on practice—lenses of appreciation’,authors address the following themes:‘Relational connections in the doctor–patient partnership’,‘Feminism and family medicine’,‘Positive family medicine’,‘mindful practice’,‘The new,old ethics of family medicine’,‘Public health,prevention and populations’,‘Information mastery in family medicine’and‘Clinical courage.’may readers nurture their curiosity through these essays.

关键词： thematic illustration doctor

A simulation study for a cost-effective PET-like detector system intended to track particles in granular assemblies

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Particuology 2024年第1期84卷 117-125页

作者： Josephine Oppotsch Antonios Athanassiadis miriam Fritsch Fritz-Herbert Heinsius thomas Held Nikoline Hilse Viktor Scherer matthias Steinke Ulrich Wiedner Ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

Since many industrial applications rely on the processing of densely packed and moving granular ma-terial,obtaining bulk internal information on the particle movement inside the reactors is of great *** information can be delivered by Positron Emission Particle Tracking(PEPT).By marking pellets with a positron-emitting radioisotope,the position of these tracer particles can be determined via the time-of-flight differences of the emitted gamma-ray *** current paper proposes a PET-like detector system based on cost-effective organic plastic scintillators instead of the more common but expensive inorganic *** system is currently under construction and was tested for its resolution and efficiency in this simulation *** monte Carlo simulations and the software toolkit Geant4,three different geometries(an empty glass box,a generic grate system,and a cubic box of 1 m3 completely filled with pellets)were investigated,leading to a spatial resolution in the millimeter range and an efficiency,defined as the ratio of reconstructed decay locations to simulated decays,of 2.7%,1.4%,and 0.3%.

关键词： Positron emission particle tracking Geant4 monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPms)

molecular Docking Studies on Streptomycin Antileishmanial Activity

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Open Journal of Physical Chemistry 2024年第2期14卷 36-48页

作者： Todd A. Young matthew George Jr. Ayele Gugssa william m. Southerland Yayin Fang Clarence m. Lee Department of Biology Howard University Washington DC United States Department of Biochemistry and molecular Biology Howard University Washington DC United States

Resistance to pentavalent antimonial drugs and the lack of vaccines make it urgent to find novel therapeutic options to treat Leishmaniasis, a tropical disease caused by the Leishmania protozoan parasite. The study reported here is to investigate if Streptomycin, an aminoglycoside, and Amphotericin B, the second-line treatment drug, exhibit antileishmanial activity through a similar mechanism. By using mOE (molecular Operating Environment), we performed molecular docking studies on these drugs binding to a range of targets including ribosome targets in Leishmania and H. sapiens. Our study shows that the two drugs do not bind to the same pockets in Leishmania targets but to the same pockets in the human ribosome, with some differences in interactions. moreover, our 2D maps indicated that Amphotericin B binds to the A-site in the human cytoplasmic ribosome, whereas streptomycin does not.

关键词： Leishmaniasis Streptomycin Amphotericin B molecular Docking Aminoglycosides Antileishmanial

Tribological behavior of shape-specific microplate-enriched synovial fluids on a linear two-axis tribometer

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Friction 2024年第3期12卷 539-553页

作者： Agnese FRAGASSI Antonietta GRECO martina DI FRANCESCO Luca CESERACCIU Aiman ABU AmmAR Israel DVIR thomas Lee mOORE Haytam KASEm Paolo DECUZZI Laboratory of Nanotechnology for Precision medicine Fondazione Istituto Italiano di TecnologiaGenova 16163Italy Department of Chemistry and Industrial Chemistry University of GenovaGenoa 16146Italy materials Characterization Facility Istituto Italiano di TecnologiaGenova 16163Italy Department of Pharmaceutical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel Department of mechanical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel

Nano-and micro-particles are being increasingly used to tune interfacial frictional properties in diverse applications,from friction modifiers in industrial lubrication to enhanced biological fluids in human osteoarthritic ***,we assessed the tribological properties of a simulated synovial fluid enriched with non-spherical,poly lactic-co-glycolic acid(PLGA)microparticles(μPL)that have been previously demonstrated for the pharmacological management of osteoarthritis(OA).Three different μPL configurations were fabricated presenting a 20μm×20μm square base and a thickness of 5μm(thin,5H μPL),10μm(10H μPL),and 20μm(cubical,20H μPL).After extensive morphological and physicochemical characterizations,the apparent Young’s modulus of the μPL was quantified under compressive loading returning an average value of~6 kPa,independently of the particle ***,using a linear two-axis tribometer,the static(μ_(s))and dynamic(μ_(d))friction coefficients of the μPL-enriched simulated synovial fluid were determined in terms of particle configuration and concentration,varying from 0(fluid only)to 6×10^(5) μPL/*** particle morphology had a modest influence on friction,possibly because the μPL were fully squeezed between two mating surfaces by a 5.8 N normal load realizing boundary-like lubrication ***,friction was observed to depend on the dimensionless parameterW,defined as the ratio between the total volume of the μPL enriching the simulated synovial fluid and the volume of the fluid *** coefficients of friction were documented to grow withWreaching a plateau of μ_(s)~0.4 and μ_(d)~0.15,already at Ω~2×10^(-3).Future investigations will have to systematically analyze the effect of sliding velocity,normal load,and rigidity of the mating surfaces to elucidate in full the tribological behavior of μPL in the context of osteoarthritis.

关键词： osteoarthritis microparticles tribology synovial fluid pin on plate

Effect of vaccinations and school restrictions on the spread of COVID-19 in different age groups in Germany

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Infectious Disease modelling 2024年第4期9卷 1250-1264页

作者： Christiane Dings Dominik Selzer Nicola Luigi Bragazzi Eva mohler markus Wenning thomas Gehrke Ulf Richter Alexandra Nonnenmacher Folke Brinkmann Tobias Rothoeft michael Zemlin thomas Lücke Thorsten Lehr Department of Clinical Pharmacy Saarland University66123SaarbrückenGermany Department of Child and Adolescent Psychiatry Saarland University Hospital66421HomburgGermany medical Association Westfalen-Lippe48151MünsterGermany School of Education and Psychology Siegen University57072SiegenGermany University Children's Hospital Ruhr University44791BochumGermany University Children's Hospital Airway Research Center North(ARCN)German Center for Lung Research(DZL)LübeckGermany Department of General Pediatrics and Neonatology Saarland University Hospital66421HomburgGermany

With the emergence of SARS-CoV-2,various non-pharmaceutical interventions were adopted to control virus transmission,including school ***,the introduction of vaccines mitigated not only disease severity but also the spread of *** study leveraged an adapted SIR model and non-linear mixed-effects modeling to quantify the impact of remote learning,school holidays,the emergence of Variants of Concern(VOCs),and the role of vaccinations in controlling SARS-CoV-2 spread across 16 German federal states with an age-stratified *** highlight a significant inverse correlation(Spearman's ρ=0.92,pmeter estimation using the observed number of cases stratified by federal state and age allowed to assess the effects of school closure and holidays,considering adjustments for vaccinations and spread of VOCs over ***,modeling revealed significant(pmong pre-school children(0-4),children(5-11),adolescents(12-17),adults(18-59),and the elderly(60+).The transition to remote learning emerged as a critical measure in significantly reducing infection rates among children and adolescents(pmong the elderly during these periods,suggesting a shift in infection networks due to altered caregiving ***,during school holiday periods,infection rates among adolescents mirrored those observed when schools were *** exercises based on the model provided evidence that COVID-19 vaccinations might serve a dual purpose:they protect the vaccinated individuals and contribute to the broader community's safety.

关键词： COVID-19 Vaccination Non-pharmaceutical interventions Age mathematical modeling