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Transition to forefoot strike reduces load rates more effectively than altered cadence

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Journal of Sport and Health Science 2020年第3期9卷 248-257页

作者： erin e.Futrell K.Douglas Gross Darcy reisman David r.Mullineaux Irene S.davis Department of Physical Therapy Springfield CollegeSpringfieldMA 01109USA Spaulding National running Center Harvard Medical SchoolCambridgeMA 02138USA Department of Physical Therapy MGH Institute of Health ProfessionsBostonMA 02129USA Department of Physical Therapy University of DelawareNewarkDE 19713USA School of Sport and exercise Science University of LincolnBrayford PoolLincolnBrayford PoolLN67TSUK Department of Physical Medicine and rehabilitation Harvard Medical SchoolBostonMA 02115USA

Background: excessive vertical impacts at landing are associated with common running injur.es. Two primary gait-retraining inter.entions aimed at reducing impact for.es are transition to forefoot strike and increasing cadence. The objective of this study was to compare the shortand long-term effects of 2 gait-retraining inter.entions aimed at reducing landing ***: A total of 39 healthy recreational runners using a rearfoot strike and a cadence of 170 steps/min were randomized into cadence(CAD) or forefoot strike(FFS) groups. All participants perfor.ed 4 weeks of strengthening followed by 8 sessions of gait-retraining using auditory feedback. Vertical average load rates(VALr) and vertical instantaneous load rates(VILr) were calculated from the vertical ground reaction for.e cur.e. Both cadence and foot strike angle were measured using 3D motion analysis and an instrumented treadmill at baseline and at 1 week,1 month, and 6 months post ***: ANOVA revealed that the FFS group had significant reductions in VALr(49.7%) and VILr(41.7%), and changes were maintained long term. Foot strike angle in the FFS group changed from 14.2° dorsiflexion at baseline to 3.4° plantarflexion, with changes maintained long term. The CAD group exhibited significant reduction only in VALr(16%) and only at 6 months. Both groups had significant and similar increases in cadence at all follow-ups(CAD, +7.2% to 173 steps/min;and FFS, +6.1% to 172 steps/min).Conclusion: Forefoot strike gait-retraining resulted in significantly greater reductions in VALr and similar increases in cadence compared to cadence gait-retraining in the short and long term. Cadence gait-retraining resulted in small reductions in VALr at only the 6-month follow-up.

关键词： Foot strike Gait-retraining Physical therapy running Step rate

Cross-scale modeling of surface temperature and tr.e seedling establishment in mountain landscapes

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ecological Processes 2013年第1期2卷 313-327页

作者： John r Dingman Lynn C Sweet Ian McCullough Frank W davis Alan Flint Janet Franklin Lorraine e Flint earth research Institute University of California Santa BarbaraSanta BarbaraCA 93106USA U.S.Geological Sur.ey California Water Science CenterSacramentoCA 95819USA Bren School of environmental Science&Management University of California Santa BarbaraSanta BarbaraCA93106USA School of Geographical Sciences and Urban Planning Arizona State UniversityTempeAZ85287USA

Introduction:estimating surface temperature from above-ground field measurements is important for understanding the complex landscape patterns of plant seedling survival and establishment,processes which occur at heights of only several ***,future climate models predict temperature at 2 m above ground,leaving ground-surface microclimate not well ***:Using a network of field temperature sensors and climate models,a ground-surface temperature method was used to estimate microclimate variability of minimum and maximum *** lapse rates were derived from field temperature sensors and distributed across the landscape capturing differences in solar radiation and cold air drainages modeled at a 30-m spatial ***:The surface temperature estimation method used for this analysis successfully estimated minimum surface temperatures on north-facing,south-facing,valley,and ridgeline topographic settings,and when compared to measured temperatures yielded an r2 of 0.88,0.80,0.88,and 0.80,*** surface temperatures generally had slightly more spatial variability than minimum surface temperatures,resulting in r2 values of 0.86,0.77,0.72,and 0.79 for north-facing,south-facing,valley,and ridgeline topographic ***-Poisson regressions predicting recruitment of Quercus kelloggii(black oak)seedlings from temperature variables were significantly improved using these estimates of surface temperature compared to air temperature modeled at 2 ***:Predicting minimum and maximum ground-surface temperatures using a downscaled climate model coupled with temperature lapse rates estimated from field measurements provides a method for modeling temperature effects on plant *** methods could be applied to improve projections of species’range shifts under climate *** of complex topography can provide intricate microclimates that may allow species to redistribute locally as climate

关键词： Black oak Climate change Generalized linear models Microclimate Topography Spatial scale Surface temperature

INVeSTIGATION OF THe ATrP OF n-BUTYL MeTHACrYLATe USING THe Cu(I)/N,N,N',N",N"-PeNTAMeTHYLDIeTHYLeNeTrIAMINe CATALYST SYSTeM

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Chinese Journal of Polymer Science 2004年第2期22卷 195-204页

作者： Kelly A. davis Krzysztof Matyjaszewski Center for Macromolecular.engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USACenter for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USA

The polymerization of n-butyl methacrylate was investigated using the Atom Transfer radical Polymerization technique with CuBr and CuCl/N,N,N',N',N'-pentamethyldiethylenetriamine catalytic systems. Various combinations of catalyst systems and initiators were utilized in or.er to optimize the polymerization conditions and to obtain well-defined polymers (i.e. controlled molecular weights and low polydispersities). It has been found that the optimal initiator for this system is a chlorine-based initiator, when the catalyst used is a salt in conjunction with the N,N,N',N',N'- pentamethyldiethylenetriamine ligand. Bromine-based initiators tend to result in lar.e amounts of initial termination, leading to polymers with less than ideal chain end functionality, even if CuCl is used as the species to invoke the halogen exchange. Additionally, the effects of the polymerization temperature, species and the initiator structure were determined.

关键词： ATrP Atom transfer radical polymerization Controlled/living radical polymerization Butyl methacrylate Pentamethyldiethylenetriamine

Stability of fruit quality traits in diver.e water.elon cultivars tested in multiple environments

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Horticulture research 2016年第1期3卷 1-11页

作者： Mahendra Dia Todd C Wehner Penelope Perkins-Veazie richard Hassell Daniel S Price Geor.e e Boyhan Stephen M Olson Stephen r King Angela r davis Gregory e Tolla Jerome Bernier Benito Juarez Department of Horticultural Science North Carolina State UniversityRaleigh27695-7609NCUSA Plants for Human Health Institute North Carolina Research Campus NCSUKannapolis28081NCUSA Clemson University Coastal Research and Education CenterCharleston29414SCUSA Georgia County extension SW DistrictCordele31015GAUSA Department of Horticulture University of GeorgiaAthens30602GAUSA North Florida reC University of FloridaQuincy32351-5677FLUSA Department of Horticulture Science Texas A&M UniversityCollege Station77845TXUSA USDA-ArS Lane74555OKUSA Monsanto/Seminis Veg.Seeds Woodland95695CAUSA Sakata Seed America Inc.1833 Dunlap Pl.Woodland95776CAUSA

Lycopene is a naturally occurring red carotenoid compound that is found in *** has antioxidant *** content,sugar content and hollowheart resistance are subject to significant genotype×environment interaction(G×e),which makes br.eding for these fruit quality traits *** objectives of this study were to(i)evaluate the influence of years and locations on lycopene content,sugar content and hollowheart resistance for a set of water.elon genotypes,and(ii)identify genotypes with high stability for lycopene,sugar,and hollowheart resistance.A diver.e set of 40 genotypes was tested over 3 years and 8 locations across the southern United States in replicated,multi-har.est *** was tested in a subset of 10 *** were analyzed using univariate and multivariate stability statistics(BLUP-GGe biplot)using SASGxe and rGxe *** were strong effects of environment as well as G×e interaction on water.elon quality *** the basis of stability measures,genotypes were classified as stable or unstable for.each quality trait.'Crimson Sweet'is an inbred line with high quality trait performance as well as trait stability.'Stone Mountain','Tom Watson','Crimson Sweet'and'Minilee'were among the best genotypes for lycopene content,sugar content and hollowheart *** developed a stability chart based on mar.etable yield and average ranking generated from different stability measures for yield attributes and quality *** chart will assist in choosing parents for improvement of water.elon *** http://***/cucurbit/wmelon/***.

关键词： stability. sugar stability

A Sur.ey of Unbalanced Flow Diagnostics and Their Application

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作者： Jack e. davis.

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Advances in Atmospheric Sciences 2000年第2期17卷 165-183页

作者： Fuqing Zhang Steven e. Koch Christopher A. davis and Michael L. Kaplan Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC

This paper presents an extensive sur.ey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian rossby number, Psi vector, diver.ence equation, nonlinear balance equation, generalized omega-equation, and departure from fields obtained by potential vorticity (PV) inversion. The basic thoery, assumptions as well as implementation and limitations for.each of the tools are all discussed. These tools are applied to high—resolution mesoscale model data to assess the role of unbalanced dynamics in the generation of a mesoscale gravity wave event over the east Coast of the United States. Comparison of these tools in this case study shows that these various methods agr.e to a lar.e extent with each other though they differ in details. Key words Unbalanced flow - Geostrophic adjustment - Gravity waves - Nonlinear balance equation - Potential vorticity inversion - Omega equations - rossby number This research was conducted under support from NSF grant ATM-9700626 of the United States. The numerical computations described herein were perfor.ed on the Cray T90 at the North Carolina Supercomputing Center and the Cray supercomputer at the NCAr Scientific Computing Division, which also provided the initialization fields for the MM5. Thanks are extended to Mark Stoelinga at University of Washington for the rIP post-processing package.

关键词： Unbalanced flow Geostrophic adjustment Gravity waves Nonlinear balance equation Potential vorticity inversion Omega equations rossby number

A linear regression model (LrM) for groundwater chemistry in and around the Vaniyambadi industrial area, Tamil Nadu, India

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Chinese Journal Of Geochemistry 2013年第1期32卷 19-26页

作者： Sajil Kumar P.J. davis Delson P. Vernon J.G. James e.J. Brandenburg Technical University Cottbus-03046 Germany ITALCONSULT Riyadh-11421 Saudi Arabia Budapest University of Technology and economics (BMe) Budapest-Pf. 91 H-152 Hungary Water Institute Karunya UniversityCoimbatore-641114 India

A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during January 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the or.er of Na e of anions were in the or.er of Cl respectively. This was in agr.ement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and SO4 were recor.ed near the tanner.es that operate within the study area. While the elevated concentrations of HCO3 and F were obser.ed away from the tanner.es. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. results of the linear regression model yielded 11 regression equations for the 5 most cor.elated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanner.es and geological formations in the study area, which confir.ed the results of major ion chemistry.

关键词：线性回归模型地下水化学工业区印度 LrM 聚类分析物理化学参数研究区域

regulation of protein degradation pathways by amino acids and insulin in skeletal muscle of neonatal pigs

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Journal of Animal Science and Biotechnology 2014年第3期5卷 299-309页

作者： Agus Suryawan Teresa A davis United States Department of Agriculture/Agricultural research Service Children's Nutrition research Center Department of PediatricsBaylor College of Medicine

Background： The rapid gain in lean mass in neonates requires greater rates of protein synthesis than degradation. We previously delineated the molecular mechanisms by which insulin and amino acids, especially leucine, modulate skeletal muscle protein synthesis and how this changes with development. In the cur.ent study, we identified mechanisms involved in protein degradation regulation. In experiment 1,6- and 26-d-old pigs were studied during 1） euinsulinemic-euglycemic-euaminoacidemic, 2） euinsulinemic-euglycemiohyperaminoacidemic, and 3） hyperinsulinemic-euglycemic-euaminoacidemic clamps for 2 h. In experiment 2, 5-d-old pigs were studied during 1） euinsulinemic-euglycemic-euaminoacidemic-euleucinemic, 2） euinsulinemic-euglycemic-hypoaminoacidemic- hyper.eucinemic, and 3） euinsulinemic-euglycemic-euaminoacidemic-hyper.eucinemic clamps for 24 h. We determined in muscle indices of ubiquitin-proteasome, i.e., atrogin-1 （MAFbx） and muscle rING-finger protein-1 （MurF1） and autophagy-lysosome systems, i.e., unc51-1ike kinase 1 （UKL1）, microtubule-associated protein light chain 3 （LC3）, and lysosomal-associated membrane protein 2 （Lamp-2）. For comparison, we measured ribosomal protein 56 （rpS6） and eukaryotic initiation factor 4e （elF4e） activation, components of translation initiation. results： Abundance of atrogin-1, but not MurF1, was greater in 26- than 6-d-old pigs and was not affected by insulin, amino acids, or leucine. Abundance of ULK1 and LC3 was higher in younger pigs and not affected by treatment. The LC3-11/LC3-1 ratio was reduced and ULK1 phosphorylation increased by insulin, amino acids, and leucine. These responses were more profound in younger pigs. Abundance of Lamp-2 was not affected by treatment or development. Abundance of elF4e, but not rpS6, was higher in 6- than 26-d-old-pigs but unaffected by treatment. Phosphorylation of elF4e was not affected by treatment, however, insulin, amino acids, and leucine stimulated rpS6 phosphorylation, and the resp

关键词： Amino acids Autophagy Insulin Leucine Muscle Neonate Protein degradation Protein synthesis,Swine Ubiquitin

evidence for cold events in the early Holocene from the Guliya ice core, Tibetan Plateau,China

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Chinese Science Bulletin 2002年第17期47卷 1422-1427页

作者： WANG Ninglian YAO Tandong L.G.Thompson K.A.Henderson M.e.davis Key Laboratory of Ice Core and Cold regions environment Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Byrd Polar research Center the Ohio State UniversityColumbusOH43210USA

evidence for the '8.2 ka cold event' has been provided mostly from the circum-North Atlantic area. However, whether this cold event occur.ed in other places is a key to understanding its cause. Here, we provide the evidence for the '8.2 ka cold event' from the Guliya ice core in the northwest Tibetan Plateau, and it was found that the peak cooling (-8.3-8.2 ka) in this ice core was about 7.8-10°C, which was lar.er than the cooling in the North Atlantic region. The primary causes for this episode were diminished solar activity and weakened thermohaline circulation. Moreover, another weak cold event, centered about 9.4 ka, was also recor.ed in the Guliya ice core record. These two cold events were concur.ent with the ice-rafting episodes in the North Atlantic during the early Holocene, which implies that the millennial-scale climatic cyclicity might exist in the Tibetan Plateau as well as in the North Atlantic.

关键词： Guliya ice core early Holocene abrupt climate change solar activity thermohaline circulation.