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Animal Nutrition 2023年第1期12卷 276-283页

作者： ashley england Kosar Gharib-Naseri Sarbast KKheravii Shu-Biao Wu School of Environmental and Rural Science University of New EnglandArmidaleNSW2351Australia

Male and female broiler chickens differ in their growth performance,carcass part weights and nutrient *** potential reasons for these differences have been explored by looking at differences in nutrient digestibility,nutrient transporter gene expression as well as gut microbiota populations between male and female *** have shown that male broilers have higher crude protein requirements compared to female *** expression of monosaccharide and amino acid transporters show conflicting results as expression depends on the interactions between sex and bird age and breed as well as which tissue is *** in microbiota populations between the genders were reported which may contribute towards performance differences,however research in this area is *** differences observed between the sexes contribute to increased variation in nutrition trials,and the potential to rear birds as equally mixed-sex becomes an option to reduce the variation introduced by the sex *** in rearing options obviously would only be feasible provided a quick,practical and cost-effective method of sexing birds is available,a topic that is also discussed in this review.

关键词： Sex effect Chicken Gut microbiota Nutrient transporter gene expression Sexing method

Cluster and Condensed Phase Properties of Light Elements (especially B, C, N, Na and Si)

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Journal of Materials Science & Technology 1997年第4期13卷 241-244页

作者： ***(Oxford University Oxford, england) Oxford University Oxford United Kingdom Egham Surrey TW20 ODU 6 Northcroft Road United Kingdom

Amorphous forms of C will first be compared and contrasted with amorphous Si, the differences in chemical bonding being emphasized in relation to atomic structure. After a brief discussion of ordered layers of graphite and of BN, some attention will be focused on BN cages and polymers and on C nanotubes. Finally properties of Na metal clusters will be discussed, including fission of such charged clusters

关键词： Si especially B Rev Figure Cluster and Condensed Phase Properties of Light Elements Na and Si

Abiotic predictors of fine sediment accumulation in lowland rivers

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International Journal of Sediment Research 2022年第1期37卷 128-137页

作者： Morwenn McKenzie Judy england Ian D.L.Foster Martin A.Wilkes Geography and Environment Loughborough University Centre for Agroecology Water & Resilience Coventry University Research Environment Agency Howbery Park Environmental and Geographical Sciences University of Northampton Learning Hub University Drive Geography Department Rhodes University

The delivery of excessive fine sediment (particles<2 mm in diameter) to rivers can cause serious deleterious effects to aquatic ecosystems and is widely acknowledged to be one of the leading contributors to the degradation of rivers *** advances in using biological methods as a proxy,physical measures remain an important method through which fine sediment can be *** aim of this study was to provide further insights into the environmental variables controlling sediment accumulation in lowland gravel bed *** sampled 21 sites,during spring and autumn,selected to cover a gradient of excess fine *** sediment was sampled using a range of methods including visual assessments,the disturbance method,and suspended sediment concentrations.A range of abiotic predictors was measured during sampling,and hydrological and antecedent flow indices were derived from local flow gauging station *** results show reach scale visual estimates of fine sediment to be significantly and highly correlated with fully quantitative estimates of total surface *** regression analysis showed that flow variables (regime,antecedent,and local flow characteristics)were strong predictors of deposited sediment metrics but poor predictors of suspended *** content was shown to be relatively independent of total sediment quantity and is likely driven by other factors which influence the supply and breakdown of organic matter.

关键词： Deposited sediment Suspended sediment Visual assessments Disturbance Sediment sampling

A GPA diagnostic system foraeroengine applications

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航空动力学报 2007年第6期22卷 898-908页

作者： Yi-Guang Li(School of Engineering,Cranfield University,Cranfield,Bedford MK43 0AL,england) School of Engineering Cranfield University England

In this research,a GPA(Gas Path Analysis) diagnostic system enhanced with GPA Index is described for gas path sensor and component fault diagnosis.A method of measurement correction is used in order that the measurement data obtained at un-standard ambient and operating conditions can be used for diagnostic *** developed diagnostic system has been implemented into a Cranfield University gas turbine performance and diagnostic analysis software PYTHIA for gas turbine performance degradation *** developed method and software have been applied to a model aero gas turbine engine to test the effectiveness of the *** analysis shows that the developed diagnostic system can diagnose degraded sensor and components effectively using performance deviation measured at un-standard ambient and operational ***,the idea of the diagnostic approach can be applied to different gas turbine engines.

关键词：航空发动机燃气涡轮诊断系统气体分解

Mechanical Properties of Si and Some d-electron Metals:Force Laws, Electron Correlation and Bond-breaking

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Journal of Materials Science & Technology 1999年第4期15卷 289-295页

作者： N.H.MarChOxford University Oxford englandPrivate address: 6 Northcroft Road, Egham, Surrey,TW20 ODU, england Univ Oxford Oxford England

The coordination-dependent force fleld of TersofF for covalently bonded Si has been used tocalculate the cleavage force as a function of interplanar separation and hence to estimate surfaceenergies. This force field is already fitted to density functional results. The relation to bond-breaking and electron correlation will be emphasized. Finnis-Sinclair-type many-body potentialshave then been used to treat some d-electron metals. In particular, results for cleavage forcein bcc Fe will be presented, and also some calculations as two perfectly planar Fe surfaces arerubbed together' at different interplanar separations. Finally, lattice dynamical models for thesteady-state propagation of a screw dislocation, and then of a crack, will be used, again within abond-breaking type of force field. For the screw dislocation propagation. a solitary wave equationis shown to follow in the 'almost continuum' limit. Energy radiated by phonons as the dislocationmoves can thereby be calculated.

关键词： Mechanical Properties of Si and Some d-electron Metals Rev Electron Correlation and Bond-breaking Si

To bridge or not to bridge:summary of the new evidence in endovascular stroke treatment

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Stroke & Vascular Neurology 2022年第3期7卷 179-181页

作者： Anna Podlasek Permesh Singh Dhillon Waleed Butt Iris Q Grunwald Timothy J england Tayside Innovation MedTech Ecosystem(TIME) University of DundeeDundeeUK NIHR Nottingham Biomedical Research Centre University of NottinghamNottinghamUK Interventional Neuroradiology Nottingham University Hospitals NHS TrustNottinghamUK Interventional Neuroradiology University Hospitals Birmingham NHS TrustBirminghamUK Stroke Division of Mental Health and Clinical NeurosciencesSchool of MedicineUniversity of NottinghamNottinghamUK Stroke University Hospitals of Derby and Burton NHS Foundation TrustDerbyUK

WHAT IS ALREADY KNOWN Recently published summaries and meta-analyses of four randomised controlled trials(RCTs)1-5 comparing direct mechan-ical thrombectomy(dMT)and bridging therapy with intravenous(IV)thrombolytics(alteplase)suggested that dMT is non-inferior to bridging therapy to achieve good functional outcome 3 months after stroke(modified Rankin Score 0-2)with the non-inferiority margin(NIM)<−5%.

关键词： intravenous bridging treatment

Lessons from Rotor 37

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Journal of Thermal Science 1997年第1期6卷 1-13页

作者： J.D. Denton(Whittle Laboratory Cambridge University Engineering Dept., Cambridge, england) Whittle Laboratory Cambridge University Engineering Dept. Cambridge England

NASA rotor 37 was used as a ’blind’ test case for turbomachinery CFD by the Turbimachinery Com-mittee of the IGTI. The rotor is a transonic compressor with a tip speed of 454 m/s (15OO ft/s) anda relatively high pressure ratio of 2.1. It was tested in isolation with a circumferentially uniform inletflow so that the flow through it should be steady apart from any effects of passage to passage geometry variation and mechanical vibration. As such it represents the simplest possible type of test forthree-dimensional turbomachinery flow solvers. However, the rotor still presents a real challenge to3D viscous flow solvers because the shock wave-boundary layer interaction is strong and the effects ofviscosity are dominant in determining the flow deviation and hence the pressure ratio. Eleven ’blind’solutions were submitted and in addition a ’non-blind’ solution was used to prepare for the exercise-This paper reviews the fiow in the test case and the comparisons of the CFD solutions with the testdata. Lessons for both the Flow Physics in transonic has and for the application of CFD to suchmachines are pointed out.

关键词： transonic compressor rotor shock wave-boundary layer interation CFD ‘blind’ solutions

Narrow versus broad:sexual dimorphism in the wing form of western European species of the subgenus Avaritia(Culicoides,Ceratopogonidae)

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Integrative Zoology 2021年第5期16卷 769-784页

作者： Francesc MUÑOZ-MUÑOZ Nonito PAGÈS Ana.F.DURAO Marion england Doreen WERNER Sandra TALAVERA Departament de Biologia Animal de Biologia Vegetal i d’EcologiaFacultat de BiociènciesUniversitat Autònoma de BarcelonaBarcelonaSpain Centre de Recerca en Sanitat Animal(CReSA) UAB-IRTACampus de la Universitat Autònoma de BarcelonaBarcelonaSpain CIRAD UMR ASTREGuadeloupeFrance ASTRE CIRADINRAeUniversitéde MontpellierMontpellierFrance The Pirbright Institute SurreyUK Leibniz-Centre for Agricultural Landscape Research MünchebergGermany

While wing form is known to differ between males and females of the genus Culicoides,detailed studies of sexual dimorphism are *** this study,we analyze sex-specific differences in the wing form of 5 species of the subgenus Avaritia,using geometric morphometrics and comparative phylogenetic *** results confirm the existence of marked sexual dimorphism in the wing form of the studied species and reveal for the first time that while there is a shared general pattern of sexual shape dimorphism within the subgenus,sexual size dimorphism,and particular features of sexual shape dimorphism differ among *** shape dimorphism was found to be poorly associated to size and the evolutionary history of the *** tight association of sexual shape dimorphism with aspect ratio suggests that the shape of the wing is optimized for the type of flight of each sex,that is,dispersal flight in females versus aerobatic flight in ***,the fact that interspecific shape differences are greater and more strongly associated to aspect ratio in males than in females might be indicating that in males the selective pressures affecting flight performance characteristics are more heterogeneous and/or stronger than in females among the studied species.

关键词： aspect ratio geometric morphometrics phylogenetic signal shape size

The Flowers of the Astrological Zodiac

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英语画刊（高三·社会综合版） 2009年第3期 30-31页

作者： Angela england

A MAGNUS EXPANSION FOR THE EQUATION Y'= AY - YB

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Journal of Computational Mathematics 2001年第1期19卷 15-26页

作者： Arieh Iserles (Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, england) University of Cambridge 英国 CB3 9EW

The subject matter of this paper is the representation of the solution of the linear differential equation Y = AY - YB, Y(0) = Yo, in the form y(t) = eΩ(t)Y0 and the representation of the function n as a generalization of the classical Magnus expansion. An immediate application is a new recursive algorithm for the deriVation of the Baker- Campbell-Hausdorff formula and its symmetric generalization.

关键词： Geometric integration Magnus expansions B aher- Campbell- Hausdorff formula.