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Pacing profiles and tactical behaviors of elite runners

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Journal of Sport and Health Science 2021年第5期10卷 537-549页

作者： arturo Casado Brian Hanley Pedro Jimenez-Reyes Andrew Renfree Faculty of Health Sciences Isabel I UniversityBurgos 09003Spain Carnegie School of Sports Leeds Beckett UniversityLeeds LS63QSUK Centre for Sport Studies Rey Juan Carlos UniversityMadrid 28943Spain Institute of Sport and Exercise Science University of WorcesterWorcester WR26AJUK

The pacing behaviors used by elite athletes differ among individual sports,necessitating the study of sport-specific pacing ***,pacing behaviors adopted by elite runners differ depending on race ***“all-out”strategy,characterized by initial rapid acceleration and reduction in speed in the later stages,is observed during 100 m and 200 m events;400 m runners also display positive pacing patterns,which is characterized by a reduction in speed throughout the ***,800 m runners typically adopt a positive pacing strategy during paced“meet”***,during championship races,depending on the tactical approaches used by dominant athletes,pacing can be either positive or negative(characterized by an increase in speed throughout).A U-shaped pacing strategy(characterized by a faster start and end than during the middle part of the race)is evident during world record performances at meet races in 1500 m,5000 m,and 10,000 m *** a parabolic J-shaped pacing profile(in which the start is faster than the middle part of the race but is slower than the endspurt)can be observed during championship 1500 m races,a negative pacing strategy with microvariations of pace is adopted by 5000 m and 10,000 m runners in championship *** cross country and marathon championship races are characterized by a positive pacing strategy;whereas a U-shaped pacing strategy,which is the result of a fast endspurt,is adopted by 3000 m steeplechasers and half *** contrast,recent world record marathon performances have been characterized by even pacing,which emphasizes the differences between championship and meet races at distances longer than 800 *** reviewed suggest further recommendations for *** the whole race,800 m runners should avoid running wide on the *** turn,during major championship events,1500 m,5000 m,and 10,000 m runners should try to run close to the inside of the track as much as possible during t

关键词： Athletics Distance running Pacing Sprinting

Remediation effect of compost on soluble mercury transfer in a crop of Phaseolus vulgaris

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Journal of Environmental Sciences 2015年第5期27卷 61-67页

作者： Nora E.Restrepo-Sánchez Liliana acevedo-Betancourth Beatriz Henao-murillo Carlos Peláez-Jaramillo Interdisciplinary Group of molecular Studies (GIEm) Institute of Chemistry Faculty of Natural and Exact Sciences University of Antioquia

We studied the dynamics of mercury（Hg） transfer in Phaseolus vulgaris plants grown in soil with Hg-doped compost at the maximum levels permitted by Colombian law on organic amendments. Quantitative evaluation of transfer was made in different plant organs： roots,stem, leaves, pods and seeds. matrix effect was determined in doped soil assays, using soil with and without addition of compost. Results showed that the use of organic matter reduced Hg transfer to the plant and the amount transferred was differentially distributed to the organs. We observed an inverse relationship between concentration and distance from the body to the root. It was evident that transfer was mediated by quantitative factors;the greater the presence of mercury in soil, the larger the amount that will be *** also indicate the remedial effect of compost and the presence of a barrier, at the root level, against mercury translocation to the plant aerial parts.

关键词： Trophic transfer mercury Organic matter Soil pollution Remediation

Landform Instability and Land-use Dynamics in Tropical High mountains, Central mexico

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Journal of mountain Science 2012年第3期9卷 414-430页

作者： GARCíA-ROmERO arturo ACEVES-QUESADA José Fernando ARREDOndo-LEóN Carlos Departamento de Geografía Física Instituto de Geografía Universidad Nacional Autónoma de México. Circuito exterior s/n Ciudad Universitaria 04510 Mexico Distrito Federal Mexico Unidad Académica de Estudios Regionales de la Coordinación de Humanidades Universidad Nacional Autónoma de México

This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the mexican Volcanic Belt mountain range (central mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.

关键词： Landform instability multi-criteriaEvaluation Analysis Land-use change and processes Tuxpan River Basin

Update on management of gastric varices

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World Journal of Hepatology 2019年第3期11卷 250-260页

作者： Louisa J Vine mohsan Subhani Juan G acevedo South West Liver Unit University Hospitals Plymouth NHS Trust

Gastric varices(GV) have different physiology and clinical characteristics compared to oesophageal varices(OV). There is little information about the management of GV. most part of the recommendations is extrapolated from studies where the majority of participants had OV. Thus, most recommendations lack of strong evidence. This is a comprehensive review on all aspects of management of GV, i.e., primary, secondary prophylaxis and management of acute bleeding. The papers on which international societies' recommendations are based are scrutinised in this review and areas of research are identified.

关键词： Gastric varices Oesophageal varices Portal hypertension Cirrhosis

Environmental Factors that Affect Primary Plant Succession Trajectories on Lahars(Popocatépetl Volcano,mexico)

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Journal of mountain Science 2015年第5期12卷 1254-1266页

作者： GARCIA-ROmERO arturo ALANIS-ANAYA Rocío marisol mUNOZ-JImENEZ Julio Departamento de Geografía Física Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Laboratorio de Análisis Geoespacial Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Departamento de A.G.R.y Geografía Física Facultad de Geografía e HistoriaUniversidad Complutense de Madrid.Calle Profesor Aranguren s/nCiudad Universitaria28040MadridSpain

The earliest stages of plant succession on severely disturbed sites usually follow highly unpredictable trajectories. However, in the Popocatépetl volcano area(50 km SE of mexico City),the development of physiognomically distinct primary plant communities suggests the occurrence of various successional trajectories only 10 years after the onset of colonization of a temperate forest on lahars. To characterize plant communities and determine the environmental factors that drive the differences observed between plant communities and their successional trajectories, we monitored 64 circular sample plots(3.14 m2) from 2002 to 2011. We examined the plant communities' composition and structure in terms of their species richness and abundance, plant cover, and maximum stem height,and recorded 13 environmental factors related to the volcanic deposit characteristics, microclimate, soil,flow dynamics and gravitational processes. A cluster analysis of the species abundance data showed that,by 2011, six plant community types(CT's) had established, including grasslands, and open, dense and very dense shrub lands. As these communities developed over the same period of time and within the same overall ecosystem, then these plant community types were interpreted as different stages of the same successional trajectory. Two sequential main stages that drive regeneration were identified from this successional trajectory: a) the first four years are characterized by a steady increase in species richness and physiognomic development(plant size and coverage), mostly dominated by Baccharis conferta, Eupatorium glabratum and Senecio barbajohannis; b) from the sixth year onwards, a continued increase in the abundance of those same species led to the development of the dense shrubland *** in the availability of soil resources and disturbances linked to recent lahar flows were the main factors accounting for such differences.

关键词： Ecosystem regeneration Plantcolonization Primary succession Temperate forest Light exposure Elevation Soil Slope aspect

Biogeographic patterns of the myxomycete biota of the Americas using a parsimony analysis of endemicity

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Fungal Diversity 2013年第2期59卷 159-177页

作者： arturo Estrada-Torres Diana Wrigley de Basanta Carlos Lado Centro de Investigación en Ciencias Biológicas Universidad Autónoma de TlaxcalaApartado Postal 183Tlaxcala 90000 TlaxcalaMexico Real Jardín Botánico de madrid CSIC Plaza de Murillo 228014MadridSpain

myxomycetes are microorganisms frequently considered to be of cosmopolitan distribution,however as studies in unexplored areas have intensified,more information has become available on the patterns of distribution of these organisms,but no historical or cladistic biogeographic approaches have been applied to understand such *** this study a parsimony analysis of endemicity(PAE)was used in order to generate a preliminary hypothesis on the biogeographic relationships of 13 American areas in which a well-known myxomycete biota *** general terms the hypotheses of the relationship between the myxomycete assemblages of areas used in this study agree with those reported for other groups of *** appear to show that a historical-geographic pattern influences the distribution of myxomycetes as much as environmental *** main clades were found in the analysis,with the first one including the two subantarctic localities,the second one representing the South American transition zone and the last one including all the Neotropical and Nearctic areas,but arranged into two subclades,one with the arid areas and the other with the tropical and temperate humid *** clade or subclade in the cladogram is supported by the presence of several morphospecies,some of which appear to represent endemic species restricted to specific geographic *** results of this analysis are proposed as a working hypothesis that can perhaps be supported in the future with new data from other complementary regions of America or with more intense surveys in the areas already *** are inconsistent with the hypothesis of cosmopolitan distribution for these microorganisms,as they appear to indicate groups of species that are restricted to certain geographic areas,some of which may be endemic,such as those from the subantarctic forests of South America,those found exclusively in the South American arid areas or those that have been recently described from arid ar

关键词： Andean region Distribution patterns myxomycetes Nearctic Neotropics Ubiquity theory

Solution‑Processed Thin Film Transparent Photovoltaics:Present Challenges and Future Development

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Nano-micro Letters 2025年第2期17卷 566-600页

作者： Tianle Liu munerah m.S.Almutairi Jie ma Aisling Stewart Zhaohui Xing mengxia Liu Bo Hou Yuljae Cho Um-SJTU Joint Institute Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China School of Physics and Astronomy Cardiff UniversityCardiff CF243AAWalesUK Department of Electrical and Computer Engineering Yale UniversityNew HavenCT 06511USA Energy Sciences Institute Yale UniversityWest HavenCT 06516USA Future Photovoltaics Research Center Global Institute of Future TechnologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Electrical energy is essential for modern society to sustain economic *** soaring demand for the electrical energy,together with an awareness of the environmental impact of fossil fuels,has been driving a shift towards the utilization of solar ***,traditional solar energy solutions often require extensive spaces for a panel installation,limiting their practicality in a dense urban *** overcome the spatial constraint,researchers have developed transparent photovoltaics(TPV),enabling windows and facades in vehicles and buildings to generate electric *** TPV advancements are focused on improving both transparency and power output to rival commercially available silicon solar *** this review,we first briefly introduce wavelength-and non-wavelengthselective strategies to achieve *** of merit and theoretical limits of TPVs are discussed to comprehensively understand the status of current TPV *** we highlight recent progress in different types of TPVs,with a particular focus on solution-processed thin-film photovoltaics(PVs),including colloidal quantum dot PVs,metal halide perovskite PVs and organic *** applications of TPVs are also reviewed,with emphasis on agrivoltaics,smart windows and ***,current challenges and future opportunities in TPV research are pointed out.

关键词： Transparent semiconductors Solution-processable transparent solar cell Emerging solar cell materials Buildingintegrated photovoltaics

Effect of non-enzymatic glycation on collagen nanoscale mechanisms in diabetic and age-related bone fragility

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BIOCELL 2023年第7期47卷 1651-1659页

作者： JAmES LROSENBERG WILLIAm WOOLLEY IHSAN ELNUNU JULIA KAmmL DAVID SKAmmER CLAIRE acevedo Department of mechanical Engineering University of UtahSalt Lake City84112USA Institute for Building materials ETH ZurichZurichSwitzerland Department of Biomedical Engineering University of UtahSalt Lake City84112USA

Age and diabetes have long been known to induce an oxidative reaction between glucose and collagen,leading to the accumulation of advanced glycation end-products(AGEs)cross-links in collagenous *** recently,AGEs content has been related to loss of bone quality,independent of bone mass,and increased fracture risk with aging and *** of bone quality is mostly attributed to changes in material properties,structural organization,or cellular *** all these factors play a role in bone fragility disease,some common recurring patterns can be found between diabetic and age-related bone *** main pattern we will discuss in this viewpoint is the increase of fibrillar collagen stiffness and loss of collagen-induced plasticity with AGE *** study focused on recent related experimental studies and discusses the correlation between fluorescent AGEs content at the molecular and fibrillar scales,collagen deformation mechanisms at the nanoscale,and resistance to bone fracture at the macroscale.

关键词： Bone fragility Advanced glycation end-products Collagen Diabetes Aging

Allograft Survival without Immunosuppression in Landrace Pigs after 90 Days

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Open Journal of Organ Transplant Surgery 2013年第4期3卷 63-64页

作者： Rafael Valdés-Gonzalez arturo m.ndo acevedo Ana L. Rodriguez-Ventura Pedro Valencia mayoral Departamento de Cirugía Universidad Nacional Autónoma de México Ciudad de México México Departamento de Patología Hospital Infantil de México Mexico D.F. México Hospital Infantil de méxico Endocrinología Mexico D.F. México

Allotransplantation is helpful in order to maintain the life in some cases, but immunosuppression causes collateral effects. In this study, we were reporting the results of allografts in Landrace pigs, which were implanted on collagen-generator devices. After 2 weeks of implantation, the devices were carried out to assess allograft viability at 30, 60 and 90 days post implant. The implanted cells were islets of Langerhans and the aim was to prove their presence by immunohistochemistry for insulin and glucagon. The results were positive at 30, 60 and 90 days post implant. It demonstrated that the collagen-generator device permits the cell viability without using anti-rejected drugs or immunomodulating cells.

关键词： Allografts Collagen-Generator Device