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中国家禽 2006年第18期28卷 41-47页

作者： Randall S Singer charles l Hofacre

在过去的十几年里,抗生素在禽类生产中的使用方式发生了很大的变化。原因之一是取消某些抗生素的使用,如美国取消氟喹诺酮在家禽的使用以及欧盟禁用抗生素促生长剂。另外,许多大型禽业公司自发减少抗生素促生长剂的使用。抗生素使用发... 详细信息

在过去的十几年里,抗生素在禽类生产中的使用方式发生了很大的变化。原因之一是取消某些抗生素的使用,如美国取消氟喹诺酮在家禽的使用以及欧盟禁用抗生素促生长剂。另外,许多大型禽业公司自发减少抗生素促生长剂的使用。抗生素使用发生变化的主要动力还是来自于与这项措施息息相关的公共健康问题。

关键词：抗生素促生长剂养禽业氟喹诺酮健康问题发生变化禽类家禽

A segmental defect adaptation of the mouse closed femur fracture model for the analysis of severely impaired bone healing

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Animal Models and Experimental Medicine 2020年第2期3卷 130-139页

作者： Amandeep Kaur Subburaman Mohan charles H.Rundle Musculoskeletal Disease Center Research Service(151)Jerry L.Pettis Memorial Veterans Administration Medical CenterLoma LindaCAUSA Department of Medicine Loma Linda UniversityLoma LindaCAUSA Department of Orthopedic Surgery Loma Linda UniversityLoma LindaCAUSA

Objective: To better characterize nonunion endochondral bone healing and evaluate novel therapeutic approaches for critical size defect healing in clinically challenging bone repair, a segmental defect model of bone injury was adapted from the threepoint bending closed fracture technique in the murine ***: The mouse femur was surgically stabilized with an intramedullary threaded rod with plastic spacers and the defect adjusted to different sizes. Healing of the different defects was analyzed by radiology and histology to 8 weeks postsurgery. To determine whether this model was effective for evaluating the benefits of molecular therapy, BMP-2 was applied to the defect and healing then ***: Intramedullary spacers were effective in maintaining the defect. Callus bone formation was initiated but was arrested at defect sizes of 2.5 mm and above, with no more progress in callus bone development evident to 8 weeks healing. Cartilage development in a critical size defect attenuated very early in healing without bone development, in contrast to the closed femur fracture healing, where callus cartilage was replaced by bone. BMP-2 therapy promoted osteogenesis of the resident cells of the defect, but there was no further callus development to indicate that healing to pre-surgery bone structure was ***: This segmental defect adaptation of the closed femur fracture model of murine bone repair severely impairs callus development and bone healing, reflecting a challenging bone injury. It is adjustable and can be compared to the closed fracture model to ascertain healing deficiencies and the efficacy of therapeutic approaches.

关键词： bone fractures bone morphogenetic protein 2 intramedullary fracture fixation ununited fractures

Deformation induced decoupling between U-Pb and trace elements in titanite revealed through petrochronology and study of localized deformation

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Geoscience Frontiers 2023年第2期14卷 217-240页

作者： charles Kavanagh-lepage Félix Gervais Kyle larson Riccardo Graziani Abdelali Moukhsil Département des génies civils géologiques et des minesPolytechnique MontréalMontréal H3T 1J4QuébecCanada Earth and Environmental Sciences IKBSASUniversity of British Columbia Okanagan3247 University WayKelownaBC V1V 1V7Canada Natural Resources Canada Government of Canada601 Booth St.OttawaON K1A 0E8Canada Direction de l’acquisition des connaissances géoscientifiques Ministère de l’Énergie et des Ressources naturelles du Québec57004e Avenue Ouest QuébecQC G1H 6R1QuébecCanada

In this contribution,we analyzed a pair of mafic samples collected from a recently identified shear zone and its proximal footwall from the Manicouagan Imbricate Zone(MIZ)of the central Grenville Province,Québec,*** petrochronology,metamorphic phase equilibria modelling,trace element thermometry,and electron backscattered diffraction data were used to define a Pressure-Temperature-timeDeformation path for the two *** interconnected dislocation network within titanite grains,as outlined with Kerneled Average Misorientation maps,are spatially correlated with variation in the U-Pb system but not with that observed for trace element These results suggest that the U-Pb system was decoupled from trace and rare earth elements and that deformation,rather than interface-coupled dissolution-precipitation reactions or re-crystallisation,was the main driver for this *** addition to highlighting a potential pitfall of titanite petrochronology,our P-T-t-D path reveals that ductile shear zones were active later than previously suggested within the MIZ.

关键词： Titanite petrochronology U-Pb Geochronology Phase equilibria modelling Trace elements Deformation Decoupling

Human neuromuscular structure and function in old age:A brief review

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Journal of Sport and Health Science 2013年第4期2卷 215-226页

作者： Geoffrey A.Power Brian H.Dalton charles l.Rice Human Performance laboratory University of Calgary School of Kinesiology The University of British Columbia Canadian Centre for Activity and Aging School of KinesiologyFaculty of Health SciencesThe University of Western Ontario Department of Anatomy and Cell Biology The University of Western Ontario

Natural adult aging is associated with many functional impairments of the human neuromuscular *** of the more observable alterations is the loss of contractile muscle mass,termed *** loss of muscle mass occurs primarily due to a progressive loss of viable motor units,and accompanying atrophy of remaining muscle *** only does the loss of muscle mass contribute to impaired function in old age,but alterations in fiber type and myosin heavy chain isoform expression also contribute to weaker,slower,and less powerful contracting *** review will focus on motor unit loss associated with natural adult aging,age-related fatigability,and the age-related differences in strength across contractile muscle actions.

关键词： Aging Eccentric Force Motor unit Muscle atrophy Power Residual force enhancement Sarcopenia Velocity

Improved maceration techniques to study the fruit vascular anatomy of grape

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Horticultural Plant Journal 2023年第3期9卷 481-495页

作者： Zhaosen Xie Teng Fei charles F.Forney Youmei li Bo li College of Horticulture and Plant Protection Yangzhou UniversityYangzhouJiangsu225009China Kentville Research and Development Centre Agriculture and Agri-Food CanadaKentvilleNova ScotiaB4N 1J5Canada Shandong Academy of Grape JinanShandong 250199China

The visualization and evaluation of fruit vascular bundles in grape are indispensable for understanding the development and growth of the fruit. The vascular bundles in grape are as thin as human hair, and strongly adhere to flesh cells, making it difficult to isolate individual intact vessel elements. Currently there is little information about methods to characterize grape vascular tissue. In this study, we describe an easy and effective technique to visualize the xylem cell structure of the ‘Red Globe' grape(Vitis l.). The intact vascular bundles of the grape were isolated through enzymatic degradation of flesh cells by hydrolases which were effective in removing flesh cells from vascular bundles. This enabled the illustration of the fine surface structure of vessel elements and their arrangement in the vascular bundles of the grape. This modified method to separate the vascular bundles into individual vessel elements was more effective than former methods of manually shaking to isolate individual vessels. Clear images of xylem vessel arrangement and structural characteristics of individual vessel element were acquired by light microscopy(BX51, Olympus, Tokyo, Japan), transmission electron microscopy(Tecnai 12, Philips, Netherlands) and scanning electron microscopy(GeminiSEM 300, Carl Zeiss, Germany). In addition, the 3D structure of vessel elements was observed using confocal laser scanning microscopy(Zeiss: model: lSM-880, Oberkochen, Germany). The imaging techniques for visualizing and analyzing the structure of xylem vessels in grape described in this study are an improvement of past methods. An effective method to isolate grape vascular bundles from flesh cells was also developed, which enables the imaging of the fine surface structure of vessel elements and their arrangement in grape vascular bundles. By adjusting the process of maceration of vascular bundles, an easy and effective method was developed to gently disrupt the plant tissue and isolate individu

关键词： Grape Fruit Vascular bundle Vessel element Maceration Anatomy

Interference from HONO in the measurement of ambient air NO2 via photolytic conversion and quantification of NO

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Journal of Environmental Sciences 2021年第9期33卷 184-193页

作者： Nicholas J.Gingerysty charles A.Odame-Ankrah Nick Jordan Hans D.Osthoff Department of Chemistry University of CalgaryCalgary AB T2N 1N4Canada Global Analyzer Systems ltd. Calgary AB T2E 7L6Canada

The reference method to quantify mixing ratios of the criteria air pollutant nitrogen dioxide(NO_(2)) is NO-O_(3) chemiluminescence(Cl), in which mixing ratios of nitric oxide(NO) are measured by sampling ambient air directly, and mixing ratios of NO_(x)(= sum of NO and NO_(2))are measured by converting NO_(2) to NO using, for example, heated molybdenum catalyst or,more selectively, photolytic conversion(P-Cl).In this work, the nitrous acid(HONO) interference in the measurement of NO_(2) by P-Cl was *** with two photolytic NO2 converters are *** first used radiation centered at 395 nm, a wavelength region commonly utilized in *** second used light at 415 nm, where the overlap with the HONO absorption spectrum and hence its photolysis rate are *** ratios of NO_(2),NO_(x) and HONO entering and exiting the converters were quantified by Thermal Dissociation Cavity Ring-down Spectroscopy(TD-CRDS).Both converters exhibited high NO_(2) conversion efficiency(CF_(NO2);> 90%) and partial conversion of *** of CF against flow rate were consistent with photolysis frequencies of 4.2 s^(-1) and 2.9 s^(-1) for NO_(2) and 0.25 s^(-1) and 0.10 s^(-1) for HONO at 395 nm and 415 nm, *** larger than predicted from the overlap of the emission and HONO absorption *** results imply that measurements of NO2 by P-Cl marginally but systematically overestimate true NO_(2) concentrations,and that this interference should be considered in environments with high HONO:NO_(2) ratios such as the marine boundary layer or in biomass burning plumes.

关键词： Photolytic conversion of NO_(2) HONO interference

Heritability estimates for seed yield and its components in Cynodon dactylon var. dactylon (l.) Pers.

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Grass Research 2022年第1期2卷 48-53页

作者： Chengcheng Tan Yanqi Wu charles M.Taliaferro Greg E.Bell Dennis l.Martin Mike W.Smith Department of Plant and Soil Sciences Oklahoma State UniversityStillwaterOK 74078USA Oklahoma Department of Agriculture Food and Forestry2800 N.Lincoln Blvd.Oklahoma CityOK 73105USA Department of Horticulture and landscape Architecture Oklahoma State UniversityStillwaterOK 74078USA

Bermudagrass[Cynodon dactylon ***(l.)Pers.]is a major warm-season turf and forage grass *** yield is an important trait targeted for improvement in bermudagrass breeding programs because of the increased interest in seed-propagated *** the nature of genetic variation for seed yield and its components in bermudagrass would aid the development of seed-propagated *** objective of this study was to estimate the genetic variation and narrow-sense heritability for seed yield and its two major components,inflorescences prolificacy and seed set percentage in ***-five half-sib families and their respective clonal parents were evaluated at two Oklahoma locations,Perkins and Stillwater(Oklahoma,USA),over two ***-sib families were different for seed yield,inflorescences prolificacy and seed set percentage,indicating the expression of additive genes in controlling these ***×location effects were observed for seed set percentage and seed *** three traits showed family×year interaction *** was a significant family×location×year interaction in inflorescences prolificacy and seed set ***-sense heritability estimates for seed yield was 0.18 based on variance component analysis among half-sib families and ranged from 0.26 to 0.68 based on parent-offspring regressions,indicating genetic complexity of seed *** estimates were moderate(0.30−0.55)for inflorescences prolificacy and moderate to relatively high(0.41−0.78)for seed set *** results indicate that sufficient magnitudes of additive genetic variation for seed set percentage and inflorescence prolificacy permit positive response to selection and conventional progeny-based genotypic evaluation is necessary for seed yield ***:Tan C,Wu Y,Taliaferro CM,Bell GE,Martin Dl,et *** estimates for seed yield and its components in Cynodon dactylon var.

关键词： dactylon cultivar breeding

Investigations on MBSE modelling and dynamic performance assessment of an electrical trimmable horizontal stabilizer actuator

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Chinese Journal of Aeronautics 2023年第11期36卷 417-433页

作者： Wensen ZHANG Jian FU Jean-charles MARÉ Haolin MA Tianxiang XIA Yongling FU Jiangao ZHAO School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China INSA–Institut Clément Ader(CNRS UMR 5312) Toulouse 31400France Nanjing Engineer Institute of Aircraft System Jincheng AVICNanjing 211100China

With the development of power-by-wire technology for more electric aircraft,the electromechanical actuator(EMA)has the advantages to replace the conventional hydraulic servo actuator in some aerospace flight *** hydraulically powered trimmable horizontal stabilizer actuation(THSA)system is nowadays developed to be electrically *** their safety-criticality,no-back mechanism and redundant load paths are utilized to meet the flight control ***,rare literatures have introduced these functions and addressed the virtual prototyping activities from system-level point of *** paper proposed such a model of a THSA system with dual electric power sources and fault-tolerant mechanical load *** nonlinear effects of components are considered with realism,and system-level simulation test is conducted to support the model-based system engineering(MBSE)*** models are developed with a power view instead of a pure signal *** on the friction effect and compliance effect with backlash or preload,some improved and novel approaches are adopted for these crucial components and validated via experimental ***,the implemented systemlevel model enables injection of crucial ***,the simulation of the proposed model shows that it is an efficient resource to investigate the actuator’s dynamic performance,to virtually prove that the actuator meets the fail/safe constraint,and to demonstrate the soundness of the fault monitoring functions.

关键词： Electro-mechanical actuator Flight control Mechanical load path Modelling No-back mechanism

Strain-induced resonances in the dynamical quadratic magnetoelectric response of multiferroics

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npj Computational Materials 2020年第1期6卷 1156-1161页

作者： S.Omid Sayedaghaee charles Paillard Sergey Prosandeev Bin Xu laurent Bellaiche Physics Department and Institute for Nanoscience and Engineering University of ArkansasFayettevilleArkansas 72701USA Microelectronics-Photonics Program University of ArkansasFayettevilleArkansas 72701USA laboratoire Structures Propriétés et Modélisation des SolidesCentraleSupélecCNRS UMR 8580UniversitéParis-Saclay91190 Gifsur-YvetteFrance Institute of Physics and Physics Department of Southern Federal University Rostov-na-Donu 344090Russia School of Physical Science and Technology Soochow UniversitySuzhouJiangsu 215006China

For the last few years,the research interest in magnetoelectric(ME)effect,which is the cross-coupling between ferroelectric and magnetic ordering in multiferroic materials,has experienced a significant *** extensive recent studies are not only conducted towards the design of sensors,actuators,transducers,and memory devices by taking advantage of the cross-control of polarization(or magnetization)by magnetic(or electric)fields,but also aim to create a clearer picture in understanding the sources of ME responses and the novel effects associated with *** we derive analytical models allowing to understand the striking and novel dynamics of ME effects in multiferroics and further confirm it with atomistic ***,the role of strain is revealed to lead to the existence of electroacoustic magnons,a new quasiparticle that mixes acoustic and optical phonons with magnons,which results in resonances and thus a dramatic enhancement of magnetoelectric ***,a unique aspect of the dynamical quadratic ME response under a magnetic field with varying frequencies,which is the second harmonic generation(SHG),has not been discussed prior to the present *** SHGs put emphasis on the fact that nonlinearities should be considered while dealing with such systems.

关键词： quadratic dynamical resonance