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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(p0.42),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

Performance analysis of a 2D numerical model in estimating minimum fluidization velocity for fluidized beds

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颗粒学报:英文版 2023年第6期77卷 116-127页

作者： Nazmul Hossain Ralph metcalfe Department of Mechanical Engineering University of HoustonHoustonTX77004USA

The minimum fluidization velocity of a fluid-solid particle fluidized bed is the primary focus of this *** computationally economic Eulerian Granular model has been used to analyze fluidization for both gas-solid particle and liquid-solid particle fluidized *** conventional approach of finding minimum fluidization velocity(umf)is either with a pressure drop across the particle bed or the change in bed ***,these parameters are often unstable and cannot be used to generalize the degree of fluidization *** this paper,the dominant factor of unstable pressure drop estimation in the 2D Two-Fluid Model(TFM)and a key non-dimensional Euler number has been investigated in deter-mining minimum fluidization velocity for different quasi-2D fluidized beds for different bed sizes,par-ticle sizes,and particle *** assumptions and limitations of these numerical models are discussed in detail for four different fluidized bed cases.A comparative study of the drag model shows little to no influence in unstable pressure drop estimation near fluidization velocity,and all drag models perform *** is observed that particle-particle collision is not the dominant reason for unstable pressure drop near minimum ***,wall effects on the particle bed including frictional losses and wall-particle collision play a key role in unstable pressure drop calculation for the quasi-2D fluidized *** drop characteristics alone do not suffice to obtain minimum fluidization ve-locity with 2D TFM using existing ***,a different approach has been proposed to investigate minimum fluidization involving the Euler number,which has shown promising performance in deter-mining minimum fluidization velocity and characterizing fluidization with 2D *** show con-sistency in Euler number characteristics for all different fluidized bed cases considered in this *** can revitalize computationally economic 2D Eulerian simulatio

关键词： Fluidized bed Minimum fluidization velocity Fluid-solid particle flow Eulerian granularmultiphase model

通过预处理短暂诱导缺氧适应不能提高脊髓损伤后雪旺细胞移植的存活率

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神经损伤与功能重建 2023年第1期18卷 F0003-F0003页

作者： Brian T David Jessica J Curtin Jennifer L Brown Kerri Scorpio Veena Kandaswamy David J C Coutts Ana Vivinetto Paola Bianchimano Saravanan S Karuppagounder mariajose metcalfe JohnWCave Caitlin E Hill 杜一星(编译) Burke Neurological Institute White PlainsNew YorkUSA The Feil Family Brain and Mind Research Institute Weill Cornell MedicineNew YorkUSA InVitro Cell Research LLCEnglewoodNew JerseyUSA Neural Stem Cell Institute RensselaerNew YorkUSA 不详

缺氧预处理在多种损伤和疾病模型中具有保护作用,但它是否对移植到脊髓损伤(SCI)部位的细胞有益在很大程度上尚待探索。本研究分析了缺氧相关的预处理是否能保护移植到挫伤的大鼠胸髓中的雪旺细胞(SC)。雪旺细胞在移植前通过暴露于低氧(... 详细信息

缺氧预处理在多种损伤和疾病模型中具有保护作用,但它是否对移植到脊髓损伤(SCI)部位的细胞有益在很大程度上尚待探索。本研究分析了缺氧相关的预处理是否能保护移植到挫伤的大鼠胸髓中的雪旺细胞(SC)。雪旺细胞在移植前通过暴露于低氧(1%O2)或药物制剂(去铁胺或adaptaquin)诱导缺氧预处理。所有预处理方法均诱导缺氧适应,包括HIF-1α及其靶基因的表达增加。然而这些适应是短暂的,并在移植后24 h内消失。药理学预处理减弱了脊髓氧化应激,并增强了移植血管形成,但它并没有改善移植细胞的存活或感觉/运动功能的恢复。总之,这些实验结果表明,与缺氧相关的预处理在改善脊髓损伤后移植雪旺细胞的细胞存活或功能方面是无效的。本研究还揭示了在细胞移植疗法中由预处理引起的缺氧相关适应的益处并不普遍。

关键词： adaptaquin 细胞存活去铁胺缺氧适应缺氧诱导因子预处理脯氨酰羟化酶抑制脊髓损伤移植

The Jinshajiang suture zone: tectono-stratigraphic subdivision and revision of age

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Science China Earth Sciences 2000年第1期43卷 10-22页

作者：汪啸风 lan metcalfe 简平何龙清王传尚 LYichang Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Yichang 443003China Asia Centre University of New England Australia

Integrated study of rock assemblage, tectonic setting, geochemical feature, fossil contained and isotopic geochronology on the metamorphic mixed bodies, exposed in the Jinshajiang suture zone, suggests that one informal lithostratigraphic unit, the Eaqing Complex, and three tectono-stratigraphic units, the Jinshajiang ophiolitic melange, the Gajinxueshan Group and the Zhongxinrong Group, can be recognized there. It is first pointed out that the redefined Eaqing Complex might represent the Meso- to Neo-Proterozoic remnant metamorphic basement or mi-crocontinental fragment in the Jinshajiang area. The original rocks of it should be older than (1627 ±192) Ma based on the geochronological study. The zircon U-Pb age of plagiogranites within the Jinshajiang ophiolitic assemblage is dated for the first time at (294 ± 3) Ma and (340 ± 3) Ma respectively. The Jinshajiang ophiolite is approximately equivalent to the Ailaoshan ophiolite in the formation age, covering the interval from the Late Devonian to the Carboniferous. Dating of U-Pb age from basalt interbeds indicates that the redefined Gajinxueshan Group and Zhongxinrong Group may be considered Carboniferous to Permian and latest Permian to Middle Triassic in age. In geotectonic terms the Jinshajiang suture zone is thought to be a back-arc basin in the eastern margin of the Paleo-Tethys. This back-arc basin started in the Late Devonian, and formed in the Devonian-Carboniferous. The collision event around the Permian/Triassic boundary to the Middle Triassic led to the closure of the back-arc basin and formation of suture.

关键词： Jinshajiang suture zone complex ophiolitic melange Paleo-Tethys.

The development of simulator testing for total knee replacements

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Biosurface and Biotribology 2021年第2期7卷 70-82页

作者： Chase Maag Amber metcalfe Ioan Cracaoanu Casey Wise Daniel DAuger DePuy Synthes WarsawIndianaUSA DePuy Synthes LeedsUK

Professor Duncan Dowson was a pioneer in the field of tribology and simulator *** work sparked many branches of research across *** first knee simu-lator described by Dowson was intended to measure the wear performance of early total knee replacements(TKRs).The industry has since advanced to achieve simulator designs with significant improvements including multi-station,multi-axis,multi-control,and multi-environmental *** simulators are used to test and compare not only wear,but also the kinematic/kinetic behaviour of TKRs and many other TKR design interactions prior to *** has led to changes to the design of TKRs ranging from improvements to the tibial insert to the femoral component;all,in some way,thanks to Professor Duncan Dowson's inquisitive *** article provides a selective review to show the interdependencies of research and development endeavours starting with the evolution of knee simulators,the many advances in TKRs and finally the interconnection with cadaveric motion simulators.

关键词： knee testing starting

Properties of diamond tool binders with fine carbonyl Ni powder additions

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金刚石与磨料磨具工程 2008年第S1期28卷 148-151页

作者： Stephenson T F Korotkin M metcalfe S 2060 Hadwen Road Mississauga Ontario L5K 1Z9 Canada

Fine Ni powder is often added to Co and bronze-based metal binder powders for diamond tool *** is a lower cost substitute for extra-fine Co powder and increases the toughness of Co-Fe diamond binders at the expense of lower hardness and bend *** bronze-based diamond binder segments,Ni increases hardness and yield *** grades of Ni powder are used commercially with both Co and bronze-based diamond *** paper compares properties of diamond binders containing carbonyl Ni powders including standard Inco(?) T255,T123 PM and T 110 *** materials were made by ball milling or dry mixing of the fine carbonyl Ni and Fe powders with either XF Co or air atomized bronze(90/10 Cu/Sn) ***-based powder blends were hot pressed at 20～35 MPa and 700℃to 900℃.Bronze-based powder blends were cold pressed and sintered at 840℃.Apparent density,apparent hardness and bend strength(TRS) were compared for different binder compositions and processing conditions.

关键词： binder Ni powder additive diamond tool

Nonlinear terahertz metamaterial perfect absorbers using GaAs[Invited]

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Photonics Research 2016年第3期4卷 16-21页

作者： Xiaoguang Zhao Jingdi Zhang Kebin Fan Guangwu Duan Grace D.metcalfe Michael Wraback Xin Zhang Richard D.Averitt Department of Mechanical Engineering Boston University Department of Physics University of California Army Research Laboratory

We investigate the nonlinear response of terahertz(THz) metamaterial perfect absorbers consisting of electric split ring resonators on GaAs integrated with a polyimide spacer and gold ground plane. These perfect absorbers on bulk semi-insulating GaAs are characterized using high-field THz time-domain spectroscopy. The resonance frequency redshifts 20 GHz and the absorbance is reduced by 30% as the incident peak field is increased from 30 to 300 kV/cm. The nonlinear response arises from THz field driven interband transitions and intervalley scattering in the GaAs. To eliminate the Fresnel losses from the GaAs substrate, we design and fabricate a flexible metamaterial saturable perfect absorber. The ability to create nonlinear absorbers enables appealing applications such as optical limiting and self-focusing.

关键词： GaAs In Nonlinear terahertz metamaterial perfect absorbers using GaAs[Invited THz

Characteristics and source attribution of PM2.5 during 2016 G20 Summit in Hangzhou: Efficacy of radical measures to reduce source emissions

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Journal of Environmental Sciences 2021年第8期33卷 47-65页

作者： Ke Chen Sarah E.metcalfe Huan Yu Jingsha Xu Honghui Xu Dongsheng Ji Chengjun Wang Hang Xiao Jun He Department of Chemical and Environmental Engineering University of Nottingham Ningbo ChinaNingbo315100China School of Geography University of NottinghamNottinghamNG72RDUK Department of Atmospheric Science School of Environmental StudiesChina University of GeosciencesWuhan430074China School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirminghamB152TTUnited Kingdom Zhejiang Institute of Metrological Sciences Hangzhou310008China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China College of Resources and Environmental Science South-Central University for NationalitiesWuhan430074China Centre for Excellence in Regional Atmos.Environ.Institute of Urban Environment Chinese Academy SciencesXiamen361021China Key Laboratory of Carbonaceous Wastes Processing and Process Intensification Research of Zhejiang Province University of Nottingham Ningbo ChinaNingbo315100China

A field campaign was conducted to study the PM2.5 and atmospheric gases and aerosol’s components to evaluate the efficacy of radical measures implemented by the Chinese government to improve air quality during the 2016 G20 Summit in Hangzhou *** lower level of PM2.5(32.48±11.03μg/m3)observed during the control period compared to precontrol and post-control periods showed that PM2.5 was alleviated by control *** on the mass concentrations of particulate components,the emissions of PM2.5 from local sources including fossil fuel,coal combustion,industry and construction were effectively reduced,but non-exhaust emission was not reduced as effectively as *** accumulation of SNA(SO42-,NO3-,NH4+)was observed during the control period,due to the favourable synoptic weather conditions for photochemical reactions and heterogeneous *** of transboundary transport during the control period,air masses from remote areas contributed significantly to local ***,secondary organic carbon(OCsec)exhibited more sensitivity than primary organic carbon(OCpri)to control measures,and the increased nitrogen oxidation ratio(NOR)implied the regional transport of aged sec-ondary aerosols to the study ***,the results from various approaches revealed that local pollution sources were kept under control,indicating that the implementation of mitigation measures were helpful in improving the air quality of Hangzhou during G20 *** reduce ambient levels of PM2.5 further in Hangzhou,regional control policies may have to be taken so as to reduce the impact of long-range transport of air masses from inland China.

关键词： G20 Summit PM2.5 Long-range transport CMB model

The Significance of Carbon 14 in Graphite Reactor Components at End of Generation

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Journal of Environmental Protection 2019年第2期10卷 118-129页

作者： Martin metcalfe Athanasia Tzelepi National Nuclear Laboratory Stonehouse Park Stonehouse GL10 5UT UK National Nuclear Laboratory Central Laboratory Seascale CA20 1PG UK

It is estimated that there are at least 250,000 tonnes of irradiated graphite worldwide that will require eventual disposal. This graphite arises from a number of sources, but principally comprises moderator and structural materials for experimental reactors, production reactors, commercial power reactors and fuel assemblies. In the UK, a significant proportion of its irradiated graphite is classified as Intermediate Level Waste. Such waste is not heat generating but has a radioactive content exceeding 4 GBq per tonne alpha or 12 GBq per tonne beta/gamma activity. While the classification of waste is not consistent across states and proposals by individual states for the management of their graphite waste vary considerably, a common interest is the nature and distribution of its radioactive content. The radionuclides in irradiated graphite presenting the most significant long-term hazard are Carbon 14 (C-14) and Chlorine 36 (Cl-36) with half-lives of 5730 and 301,000 years respectively. For a better understanding of the way in which C-14 is produced, its distribution within irradiated graphite and realistic quantification of activity can potentially lead to improved characterization to validate its status within current or future waste classifications, segregation to reduce Intermediate Level Waste volumes, or treatment to reduce activity enabling re-classification as Low Level Waste. This paper reviews all these issues and then focuses on the significance of C-14. Some findings from a National Nuclear Laboratory study of C-14 levels in carbonaceous deposits and the underlying Magnox reactor graphite are presented to illustrate the need for thorough characterization of the waste material. These results are discussed in the context of aqueous leaching of C-14 from irradiated graphite and potential treatment options to minimize aqueous release. The paper concludes with some broader observations on the significance of C-14 in nuclear reactor graphite components and how

关键词： Intermediate Level Waste Nuclear Reactor Graphite Components