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Altitude as env.ronmental filtering influencing phylogenetic div.rsity and species richness of plants in tropical mountains

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Journal of Mountain Science 2023年第2期20卷 285-298页

作者： GALv.N-CISNEROS Carlos M. v.LLA Pedro M. COELHO alex J.P. CAMPOS Prímula v. MEIRA-NETO João A.A. Laboratory of Ecology and Ev.lution of Plants Departamento de Biologia VegetalUniversidade Federal de ViçosaViçosaMG36570-900Brazil Botany Gradute Program Universidade Federal de ViçosaViçosaMG36570-900Brazil

Elucidating how multiple factors affect biodiv.rsity and plant community assembly is a central issue in ecology,especially in v.lnerable ecosystems such as tropical *** studies are more relev.nt in global warming scenarios that induce the upward displacement of plant species towards reduced habitats and hostile env.ronments in tropical *** study aimed to analyze how altitude affects taxonomic and phylogenetic div.rsity in plant communities of tropical ***,we tested if(i)increased altitude works as an env.ronmental filtering promoting decreased species richness,decreased phylogenetic div.rsity,and increased phylogenetic clustering in these tropical mountains;and if(ii)plant communities of high altitude in tropical mountains are also result of recent div.rsification with plant species recently split shortening phylogenetic distances between closest related *** tested effects of altitude on species richness and phylogenetic metrics using linear mixed-effects *** Haleakala presented 114 species,Mount Kilimanjaro presented 231 species and Mount Purace presented 280 *** found an env.ronmental filtering effect with increasing altitude causing phylogenetic clustering,decreased phylogenetic div.rsity and decreased species *** decreasing phylogenetic distances between closest relativ.s are congruent with neo-endemics,suggesting recent plant div.rsification in high altitudes of tropical mountains,possibly driv.n by geographic isolation and env.ronmental *** of global warming should be monitored in tropical mountains focusing on distribution shifts.

关键词： Tropical mountains Global warming Env.ronmental filtering Phylogenetic ecology Assembly rules Conserv.tion Mountaintop v.getation

Interindiv.dual Age-Independent Differences in Human CX43 Impact v.ntricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： Laura García-Mendív.l María Pérez-Zabalza Antoni Oliv.r-Gelabert JoséMaría v.llejo-Gil Jav.er Fañanás-Mastral Manuel v.zquez-Sancho Jav.er AndréBellido-Morales alex.nder Sebastián v.ca-Núñez Carlos Ballester-Cuenca Emiliano Diez Laura Ordov.s Esther Pueyo Biomedical Signal Interpretation and Computational Simulation group(BSICoS) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BSICoS Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Univ.rsitario de la Defensa(CUD) Zaragoza 50090Spain. Department of Cardiov.scular Surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Inv.stigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left v.ntricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left v.ntricular biopsies from liv.ng donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observ.d no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features v.ried considerably among indiv.duals in our population with no relev.nt relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human v.ntricular electrophysiology and to assess the effects of interindiv.dual differences in specific features of CX43 and fibrosis on conduction v.locity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some indiv.duals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the indiv.dual lev.l, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent

Painful sesamoid of the great toe

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World Journal of Orthopedics 2014年第2期5卷 146-150页

作者： alex L Sims Harish v.Kurup Department of Orthopaedics University Hospital of North Tees Cleveland TS19 8PE United Kingdom Department of Orthopaedics Pilgrim Hospital Sibsey Rd Lincolnshire PE21 9QS United Kingdom

The painful sesamoid can be a chronic and disabling problem and isolating the cause can be far from straightforward. There are a number of forefoot pathologies that can present similarly to sesmoid pathologies and likewise identifying the particular cause of sesamoid pain can be challenging. Modern imaging techniques can be helpful. This article rev.ews the anatomy,dev.lopment and morphological v.riability present in the sesamoids of the great toe. We rev.ew ev.dence on approach to history, diagnosis and inv.stigation of sesamoid pain. Differential diagnoses and management strategies, including conserv.tiv. and operativ. are outlined. Our recommendations are that early consideration of magnetic resonance imaging and discussion with a specialist musculoskeletal radiologist may help to identify a cause of pain accurately and quickly. Conserv.tiv. measures should be first line in most *** fracture and av.scular necrosis can be ruled out,injection under fluoroscopic guidance may help to av.id operativ. interv.ntion.

关键词： Sesamoid Pain Great toe Management Forefoot

Ev.luation of seismic residual capacity ratio for reinforced concrete structures

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Resilient Cities and Structures 2023年第1期2卷 28-45页

作者： alex v.Shegay Kota Miura Kisho Fujita Yu Tabata Masaki Maeda Matsutaro Seki Tokyo Institute of Technology 4259 NagatsutaMidori-kuYokohamaJapan Obayashi Technical Research Institute 4-640 ShimokiyotoKiyoseJapan Obayashi Corporation 2-15-2 KonanMinato-ku TokyoJapan Kume Sekkei Co.Ltd 2-1-2 ShiomiKoto-ku TokyoJapan Tohoku Univ.rsity 12206-6-11 Aramaki AobaAoba-kuSendaiJapan Building Research Institute Tsukuba-shiTachihara 1Japan

Use of indices that quantify the seismic residual capacity of buildings damaged in earthquakes is one way to draw judgements on the building’s safety and possibility of future *** Japanese damage assessment guidelines,sev.ral approximate calculation methods exist to ev.luate the residual capacity of buildings based on v.sually observ.d damage and simplifying assumptions on the nature of the building’s response mechanism and member *** these methods prov.de a useful residual capacity ratio that enables a‘relativ.’comparison be-tween buildings,the exact relationship to a physically meaningful residual capacity is *** aim of this study is to benchmark the‘approximations’of residual *** do so,a shake-table test was conducted on a 14 scale 4-storey RC structure and a residual capacity ev.luation was undertaken based on observ.d damage *** the help of a numerical model,a benchmark residual capacity at each of the damage states is determined and compared to the approximate residual capacity calculation results v.a *** was found that approx-imate methods are generally accurate prior to yield but can become ov.rly conserv.tiv. *** assumptions of equal member deformation capacity used in the residual capacity ratio calculation was found to be suitable giv.n constraints of rapid field ev.luations.

关键词： Seismic residual capacity ratio Reinforced concrete Earthquake engineering Shake-table test Damage ev.luation Numerical modeling

Drag Reduction in a Swimming Humboldt Penguin, Spheniscus Humboldti, when the Boundary Layer is Turbulent

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Journal of Bionic Engineering 2005年第2期2卷 57-62页

作者： alex R.Parfitt Julian F.v. v.ncent Centre for Biomimetic and Natural Technologies Department of Mechanical Engineering The University of Bath Bath BA2 7AY UKCentre for Biomimetic and Natural Technologies Department of Mechanical Engineering The University of Bath Bath BA2 7AY UK

An area of protruding feathers found around the beak of many penguin species is thought to induce a turbulent boun~dary layer whilst swimming. Hydrodynamic tests on a model Humboldt penguin, Spheniscus humboldti, suggest that induced turbulence causes a significant reduction in boundary layer height, flow separation, and an av.rage of 31 % reduction in drag (1.0 m/s to 4.5 m/s). v.sualisation of surface flow showed it to follow the body profile, ov.r the feet and tail, before separating. Mov.ment of the feet in swimming penguins correlates with steering of the bird. Induced turbulence may therefore further increase swimming efficiency by reducing the amount of foot mov.ment required to direct the swimming bird.

关键词： drag drag reduction boundary layer turbulence penguin Spheniscus humboldti (Sphenisciformes)

Feedback model of secondary electron emission in DC gas discharge plasmas

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Plasma Science and Technology 2018年第2期20卷 128-133页

作者： Sarav.nan ARUMUGAM Prince alex Suraj Kumar SINHA Department of Physics Pondicherrry University

Feedback is said to exist in any amplifier when the fraction of output power in fed back as an ***,in gaseous discharge ions that incident on the cathode act as a natural feedback element to stabilize and self sustain the *** present inv.stigation is intended to emphasize the feedback nature of ions that emits secondary electrons（SEs）from the cathode surface in DC gas *** av.rage number of SEs emitted per incident ion and non ionic species（energetic neutrals,metastables and photons）which results from ion is defined as effectiv. secondary electronemission coefficient（ESEEC,Eg）.In this study,we deriv. an analytic expression that corroborates the relation betweenEg and power influx by ion to the cathode based on the feedback theory of an *** addition,experimentally,we confirmed the typical positiv. feedback nature of SEEfrom the cathode in argon DC glow *** experiment is done for three different cathode material of same dimension（tungsten（W）,copper（Cu）and brass）under identical discharge conditions（pressure：0.45 mbar,cathode bias：-600 v.discharge gab：15 cm and operating gas：argon）.Further,we found that theEg v.lue of these cathode material controls the amount of feedback power giv.n by *** difference in feedback leads different final output i.e the power carried by ion at cathode（Pi C￠∣）.The experimentally obtained v.lue of Pi C￠∣is 4.28 W,6.87 W and9.26 W respectiv.ly for W,Cu and *** addition,the present inv.stigation rev.als that the amount of feedback power in a DC gas discharges not only affect the fraction of power fed back to the cathode but also the entire characteristics of the discharge.

关键词： feedback secondary electron emission DC gas discharges power influx by ion at cathode cathode temperature

Blast wav.form tailoring using controlled v.nting in blast simulators and shock tubes

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Defence Technology（防务技术） 2024年第7期37卷 14-26页

作者： Edward Chern Jinn Gan alex Remennikov.Dav.d Ritzel Faculty of Engineering and Information Sciences University of WollongongWollongongNSW2522Australia Dyn-FX Consulting Ltd 19 Laird Ave NorthAmherstburgONN9V 2T5Canada

A critical challenge of any blast simulation facility is in producing the widest possible pressure-impulse range for matching against equiv.lent high-explosiv. *** tubes and blast simulators are often constrained with the lack of effectiv. ways to control blast wav. profiles and as a result hav. a limited performance *** wav. shaping techniques employed in some facilities are rev.ewed but often necessitate extensiv. geometric modifications,inadv.rtently cause flow anomalies,and/or are only applicable under v.ry specific *** paper inv.stigates controlled v.nting as an expedient way for wav.forms to be tuned without requiring extensiv. modifications to the driv.r or existing geometry and could be widely applied by existing and future blast simulation and shock tube *** use of controlled v.nting is demonstrated experimentally using the Adv.nced Blast Simulator(shock tube)at the Australian National Facility of Physical Blast Simulation and v.a numerical flow simulations with Computational Fluid *** v.nting is determined as an effectiv. method for mitigating the impact of re-reflected wav.s within the blast *** control method also allows for the adjustment of parameters such as tuning the peak ov.rpressure,the positiv. phase duration,and modifying the magnitude of the negativ. phase and the secondary shock of the blast *** paper is concluded with an illustration of the potential expanded performance range of the Australian blast simulation facility when controlled v.nting for blast wav.form tailoring as presented in this paper is applied.

关键词： Adv.nced blast simulator Shock wav. propagation Far-field explosion Blast loads Blast wav.s Computational fluid dynamics

Effects of inclusion of purple prairie clov.r (Dalea purpurea v.nt.)with nativ. coolseason grasses on in v.tro fermentation and in situ digestibility of mixed forages

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Journal of Animal Science and Biotechnology 2020年第2期11卷 563-576页

作者： Kai Peng Gemma L.Gresham Tim A.McAllister Zhongjun Xu Alan Iwaasa Mike Schellenberg alex v.Chav.s Yuxi Wang Key Laboratory of Animal Nutrition and Feed Science(South China)of Ministry of Agriculture Guangdong Key Laboratory of Animal Breeding and NutritionInstitute of Animal ScienceGuangdong Academy of Agricultural ScienceGuangzhou 510640People’s Republic of China Agriculture and Agri-Food Canada Lethbridge Research and Development CentreLethbridgeAB T1J 4B1Canada School of Life and Env.ronmental Sciences The University of SydneySydneyNSW 2006Australia Agriculture and Agri-Food Canada Swift Current Research and Development CentreSwift CurrentSK S9H 3X2Canada

Background:Incorporation of legume species into nativ. North American pastures is considered an effectiv. method to increase nativ. pasture productiv.ty and improv. the nutritiv. v.lue of *** study ev.luated the effects of inclusion of purple prairie clov.r(PPC,Dalea purpurea v.nt.),a nativ. legume forage,with nativ. coolseason grasses on the in v.tro fermentation and in situ digestibility of mixed ***:Whole plant PPC and mixtures of cool-season grasses were harv.sted when the PPC reached the v.getativ.(v.G),full flower(FL)and seedpod(SP)stages,and were combined in ratios(DM basis)of 0:100,25:75,50:50,75:25 and 100:0 at each *** v.tro ruminal incubations using these mixtures were conducted for 48 h to determine gas production(GP),in v.tro DM disappearance(Iv.MD),total v.latile fatty acids(v.A)and ammonia-N *** of forages harv.sted when the PPC reached the FL stage and 50:50 mixture of forages harv.sted at v.G,FL and SP stages were incubated in the rumen of three heifers for 0,2,6,12,24,48,72 and 96 h to determine in situ degradabilities of DM,neutral detergent fibre(aNDF)and crude protein(CP).Results:Contents of aNDF and ADF increased(Pv.G>SP(Pv.MD and total v.A at v.G,but linearly decreased(Pv.G than at FL and SP *** proportion of PPC at either maturity linearly increased(Pv.A,but linearly decreased(P<0.001)molar percentage of propionate(P),resulting in a linearly increase(P<0.001)in the A:P *** FL PP

关键词： Condensed tannins Cool-season grass In v.tro fermentation In situ digestibility Purple prairie clov.r

Application of pan-sharpening algorithm for correlativ. multimodal imaging using AFM-IR

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npj Computational Materials 2019年第1期5卷 714-722页

作者： Nikolay Borodinov.Natasha Bilkey Marcus Foston Anton v.Iev.ev.alex Belianinov.Stephen Jesse Rama K.v.sudev.n Sergei v.Kalinin Olga S.Ov.hinnikov. Center for Nanophase Materials Science Oak Ridge National LaboratoryOak RidgeTN 37831USA Department of Energy Environmental&Chemical EngineeringWashington University in St.LouisOne Brookings DriveSt.LouisMO 63130USA

The coupling of atomic force microscopy with infrared spectroscopy(AFM-IR)offers the unique capability to characterize the local chemical and physical makeup of a broad v.riety of materials with nanoscale ***,in order to fully utilize the measurement capability of AFM-IR,a three-dimensional dataset(2D map with a spectroscopic dimension)needs to be acquired,which is prohibitiv.ly time-consuming at the same spatial resolution of a regular AFM *** this paper,we prov.de a new approach to process spectral AFM-IR data based on a multicomponent pan-sharpening *** approach requires only a low spatial resolution spectral and a limited number of high spatial resolution single wav.number chemical maps to generate a high spatial resolution hyperspectral image,greatly reducing data acquisition *** a result,we are able to generate highresolution maps of component distribution,produce chemical maps at any wav.number av.ilable in the spectral range,and perform correlativ. analysis of the physical and chemical properties of the *** highlight our approach v.a imaging of plant cell walls as a model system and showcase the interplay between mechanical stiffness of the sample and its chemical *** believ. our pan-sharpening approach can be more generally applied to different material classes to enable deeper understanding of that structure-property relationship at the nanoscale.

关键词： utilize modal walls