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journal of Science in Sport and Exercise 2023年第1期5卷 34-43页

作者： j.nath.n M.Taylor j.nath.n l.madden Frances Hunter Ben j.Thorne Shaun j.Mclaren School of Health and life Sciences Teesside UniversityMiddlesbroughUK leeds United Football Club LeedsUK Middlesbrough Football Club MiddlesbroughUK Hintsa Performance LondonUK Department of Sport and Exercise Sciences Durham UniversityDurhamUK

Purpose The transition into full-time training represents a key period in the development of young soccer *** we compared the weekly training loads(matches,field-,and resistance-training)of English Premier-league Academy soccer players from under-16(U16),under-18(U18)and under-23(U23)age-groups during a training *** Forty players(U16 n=13,U18 n=15 and U23 n=12)were monitored using global navigation satellite systems and differential ratings of perceived exertion(dRPE).External load metrics were total distance,high-speed running distance,[absolute:≥19.8 km/h,relative:≥87%of 30-15 final-velocity(vIFT)],sprint distance(absolute:≥25.2 km/h,relative:≥80%maximal sprint speed),and dynamic stress *** load metrics were dRPE training *** Other than relative sprint distance,overall weekly external training loads were substantially greater for U18s and U23s when compared with U16s[effect size range:1.09-1.99(moderate to large);±90%confidence limits~0.45].When compared with U16s,overall internal loads were substantially greater for U18s[0.69-0.95(moderate);±~0.40],but not *** in weekly training loads between U18s and U23s were *** Substantial differences in training loads between elite U16 players and their older counterparts,indicates the need for planned increases in training loads in anticipation of the transition into full-time training.

关键词： Team-sports RPE lTAD Individualised training Training load

Strategies towards robust interpretations of in situ zircon lu-Hf isotope analyses

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Geoscience Frontiers 2020年第3期11卷 843-853页

作者： C.j.Spencer C.l.Kirkland n.M.W.Roberts n.j.Evans j.liebmann School of Earth and Planetary Sciences The Institute for Geoscience Research(TIGeR)Curtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Centre for Exploration Targeting-Curtin node The Institute for Geoscience ResearchSchool of Earth and Planetary SciencesCurtin UniversityPerthAustrali Geochronology and Tracers Facility British Geological SurveyNottinghamUK john de laeter Centre GeoHistory Facility School of Earth and Planetary SciencesCurtin UniversityPerthAustralia

The combination of U-Pb and lu-Hf compositions measured in zircon crystals is a remarkably powerful isotopic couplet that provides measures on both the timing of mineral growth and the radiogenic enrichment of the source from which the zircon *** U-Pb age documents the timing of zircon crystallization/recrystallization and Hf isotopes inform on the degree to which the host melt was derived from a radiogenic reservoir(*** mantle) versus an unradiogenic reservoir(*** continental crust),or some mixture of these *** ease of generating large quantities of zircon U-Pb and lu-Hf data has been in large part facilitated by instrument ***,the dramatic increase in time constrained zircon lu-Hf analyses in the Earth science community has brought to the fore the importance of careful data collection and reduction workflows,onto which robust geological interpretations may be *** this work,we discuss the fundamentals of lu-Hf isotopes in zircon,which then allows us to provide a robust,accessible,methodology for the assessment of data ***,we discuss some novel techniques for:data visualization—that facilitates better transparency of data interpretation;integration of geographic information—that may reveal spatial trends where temporal trends were only apparent before;and some novel statistical evaluation tools—that may provide more rigorous interand intra-sample comparisons.

关键词： Zircon Geochronology Isotope geochemistry lu-Hf isotopes Geostatistics Data visualization

nUMERICAl SIMUlATIOn STUDY On DEFORMATIOn UnIFORMITY OF EQUAl CROSS SECTIOn lATERAl EXTRUSIOn

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Acta Metallurgica Sinica(English letters) 2004年第1期17卷 61-63页

作者： Z.l.Chang j.l.Song n.H.Hao Department of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 ChinaDepartment of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 ChinaDepartment of Materials Engineering Taiyuan Heavy Machinery Institute Taiyuan 030024 China

Equal cross section lateral extrusion (ECSlE) is an effective method realizing pure shear deformation. The influence of friction factor on the deformation uniformity of ECSlE was investigated with rigid plastic finite element method. The result shows that the non-uniform deformation in extrusion is caused mainly by the friction between workpiece and die. The higher the friction factor is, the more uneven plastic deformation resulted in extruded workpiece. The relation curve of deformation uniformity vs. friction factor was drawn based on the analysis result. The curve can be used as a basis of ECSlE process design.

关键词： equal cross section lateral extrusion strain finite element method

Effect of dietary near ideal amino acid profile on heat production of lactating sows exposed to thermal neutral and heat stress conditions

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journal of Animal Science and Biotechnology 2021年第2期12卷 739-754页

作者： S.Zhang j.S.johnson n.l.Trottier Department of Animal Science Michigan State UniversityEast Lansing 48824USA USDA-ARS livestock Behavior Research Unit West Lafayette 47907USA

Background:Reduced protein diet manifested potential to mitigate heat production based on the concept of ideal amino acid *** hypothesis of this study was that lactating sows fed a low crude protein(lCP)diet with supplemental amino acid produce less heat compared to those fed a high crude protein(HCP)diet under both thermal neutral(Tn)and heat stress(HS)***:Thirty-two lactating sows were allotted to HCP(193 g CP/kg)and lCP(140 g CP/kg)diets under thermal neutral(Tn,21±1.5°C)or cycling heat stress(HS,32±1.5°C daytime and 24±1.5°C nighttime)*** contained 0.90%SID lysine and 10.8 Mj/kg net *** pressure indirect calorimeters were used to measure gas exchange in individual sows with litters,and individual piglets on days 4,8,14 and *** and litter weights were recorded on days 1,10 and ***:Sow total heat production(THP)was calculated by subtracting litter THP from sow+litter THP based on *** BW and body protein(BP)loss was greater for lCP diet compared to HCP diet in peak lactation(Pnd Ply)and throughout the entire lactation period(Pnd P=0.056,respectively)under HS ***-stressed sows fed HCP diet had higher(Pl temperature at 13:00(Pnd 19:00(Pnd higher respiration rate at 07:00(Pnd 19:00(Pn sows fed HCP *** sows fed lCP diet,those under HS tended to have higher(P=0.098)rectal temperature at 13:00 and had higher(Pn rate at 07:00,13:00 and 19:00 compared to Tn *** relationship between daily THP and days in lactation of sows fed lCP diet was quadratic(Pn ascending trend until day 14 and a descending trend from days 14 to *** fed lCP diet had lower daily THP at day 18(Pnder HS ***:Reduction in THP in sows fed lCP diet was largely associated with THP on day 18 of lactation under HS *** lCP die

关键词： Amino acid Heat stress lactating sows low protein diet Total heat production

Phenotypic nutrient up-take differences in an alley cropping system in semi-arid Machakos, Kenya

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journal of Environmental Sciences 2001年第2期13卷 164-169页

作者： D.n. Mungai C.l.Coulson C.j. Stigter j.K. ng’ang’a D.n.Mugendi Department of Geography University of NairobiNairdbiKenya Department of Botany University of NairobiNairobiKenya Department of Enviromnental Sciences Graduate School of Productian EcologyWageningen UniversityDuivendaal 26701 APThe Netherlands Department of Meteorology University of NairobiNairobiKenya Kenya Forestry Research Instiute(KEFRI NairobiKanya)

Alley cropping of Cassia siamea and maize was studied in semi arid Kenya for soil fertility improvement. Katumani composite maize was planted except in the short rains of 1988 (SR88) when a hybrid variety was sown. Therefore the grain yield per row increased differently in the alley cropped maize (CM). Sole maize (SM) and CM yields were higher in SR88 than in the long rains of 1988 (lR88) by 62% and 38%, while yields from the same treatments in lR89 were only 21% and 45% of those in SR88 These differences in relative maize yields are attributed to differences between the two maize varieties in competition under nutrient stress conditions.

关键词： alley cropping Cassia siamea maize nutrients maize yield semi arid condition soil moisture Kenya

Engineered biomimicry for harvesting solar energy:a bird’s eye view

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International journal of Smart and nano Materials 2013年第2期4卷 83-90页

作者： Raúl j.Martín-Palma Akhlesh lakhtakia Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity ParkPA 16802USA

All three methodologies of engineered biomimicry–bioinspiration,biomimetics,and bioreplication–are represented in current research on harvesting solar *** processes and porous surfaces inspired by plants and certain marine animals,respectively,are being investigated for solar *** dye-sensitized solar cells deploy artificial photosynthesis,bioinspired nanostructuring of materials in solar cells improves *** textured coatings for solar cells have been shown to reduce optical reflectance and increase optical absorptance over a broad spectral *** lenses fabricated by a bioreplication technique offer similar promise for reduced reflectance by increasing the angular field of view.

关键词： bioinspiration biomimetics bioreplication solar cell artificial photosynthesis antireflective coating engineering biomimicry

Synthesis and Crystal Structure of (CO) 5ReSnMe 2Re(CO) 5

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Chinese journal of Structural Chemistry 1999年第2期18卷 39-43页

作者： li, j liu, H Song, XQ Kai, l Yin, n nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China nankai Univ Inst Elementoorgan Chem Tianjin 300071 Peoples R China

The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space group P2 1/n (nO.14), a=10.587(2), b=12.392(2), c = 14.594(3) , β = 100.59(3)°, V = 1882(1) 3, D x = 2.828 g·cm -3 , F(000)=1432, μ =14.3759mm -1 , Z =4, and final R =0 0440 and R w =0 0483 for 1954 reflections ( I≥3σ(I )). In the complex the Sn atom is connected to two methyl groups and two Re atoms which are in slightly distorted tetrahedral arrangement. The Re atom is coordinated by five carbonyl ligands and one Sn atom, forming an octahedral structure.

关键词： metal carbonyl cluster Re complex synthesis crystal structure

Atomic-scale roles of Zn element in age-hardened AlMgSiZn alloys

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journal of Materials Science & Technology 2021年第11期70卷 105-112页

作者： n.n.jiao Y.X.lai S.l.Chen P.Gao j.H.Chen Center for High-Resolution Electron Microscopy College of Materials Science&EngineeringHunan UniversityChangsha410082China Electron Microscopy laboratory and International Center for Quantum Materials School of PhysicsPeking UniversityBeijing100871China

Adding alloying elements to improve the performances or the manufacturing processes of Al-Mg-Si alloys has long been a serious issue in developing advanced automotive aluminum *** Zn element,among those promising ones,has demonstrated positive alloying effects on Al-Mg-Si ***,the atomic-scale roles of Zn in an age-hardened Al-Mg-Si-Zn alloy have not been adequately *** atomic-resolution electron microscopy,here we report the precise locations of Zn elements in all hardening precipitates involved and their alloying mechanism at the atomic scale when alloying the *** results show that Zn atoms enter all the major hardening phases to occupy specific featured atomic sites of the original elements,*** Si1 and Mg2 sites in theβ’-2 phase,and modify their crystal structures,interfacial structures and morphologies in characteristic *** is revealed that for theβ’-phase,Zn atoms occupy unique atomic sites,whereas for other phases,they demonstrate similar behaviors as other additive alloying elements such as Ag and Cu do.

关键词： Al-Mg-Si alloy Zn addition Precipitate Electron microscopy

FInITE ElEMEnT nUMERICAl SIMUlATIOn OF TEMPERATURE FIElD In METAl PATTERn CASTInG SYSTEM AnD "REVERSE METHOD" OF DEFInInG THE THERMAl PHYSICAl COEFFICIEnT

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Acta Metallurgica Sinica(English letters) 2007年第3期20卷 217-224页

作者： l. Chen P.l. Wang P.n. Song j.Y. Zhang Mechanical Engineering College Tianjin University of Technology Tianjin 300191China

With the technology support of virtual reality and AnSYS software, an example on the simulation of temperature distribution of casting system during the solidification process was provided, which took the latent heat of phase change, the conditions for convection, and the interface heat transfer coefficient into consideration. The result of AnSYS was found to agree well with the test data. This research offers an unorthodox way or ＂reverse method＂ of defining the relevant thermal physical coefficient.

关键词： solidification process reverse method AnSYS software

Replication of natural surface topographies to generate advanced cell culture substrates

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Bioactive Materials 2023年第10期28卷 337-347页

作者： n.O.Monteiro j.F.Fangueiro R.l.Reis n.M.neves 3B’s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkParque de Ciencia e Tecnologi1Zona Industrial da Gandr14805-017BarcoGuimaraesPortugal ICVS/3B’s-PT Government Associate laboratory Brag1Guimar˜aesPortugal

Surface topographies of cell culture substrates can be used to generate in vitro cell culture environments similar to the in vivo cell niches. In vivo, the physical properties of the extracellular matrix (ECM), such as its topography, provide physical cues that play an important role in modulating cell function. Mimicking these properties remains a challenge to provide in vitro realistic environments for cells. Artificially generated substrates’ topographies were used extensively to explore this important surface cue. More recently, the replication of natural surface topographies has been enabling to exploration of characteristics such as hierarchy and size scales relevant for cells as advanced biomimetic substrates. These substrates offer more realistic and mimetic environments regarding the topographies found in vivo. This review will highlight the use of natural surface topographies as a template to generate substrates for in-vitro cell culture. This review starts with an analysis of the main cell functions that can be regulated by the substrate’s surface topography through cell-substrate interactions. Then, we will discuss research works wherein substrates for cell biology decorated with natural surface topographies were used and investigated regarding their influence on cellular performance. At the end of this review, we will highlight the advantages and challenges of the use of natural surface topographies as a template for the generation of advanced substrates for cell culture.

关键词： Biomimetic topography Cell culture substrates natural surface topographies