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Ultrastructure of the gastro intestinal tract of healthy japanese quail(Coturnix japonica) using light and scanning electron microscopy

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Animal Nutrition 2018年第4期4卷 378-387页

作者： Ngare Wilkinson Ivan Dinev William j.Aspden Robert j.hughes Ingrid Christiansen james Chapman Sheeana Gangadoo Robert j.Moore Dragana stanley Central Queensland University Institute for Future Farming Systems Poultry Cooperative Research Centre University of New England Armidale Faculty of Veterinary Medicine Trakia University South Australian Research and Development Institute Pig and Poultry Production Institute School of Animal and Veterinary Sciences University of Adelaide School of Science RMIT University Department of Microbiology Monash University

The japanese quail(Coturnix japonica) are popular both as an alternative protein source and as a model of choice for scientific research in several disciplines. There is limited published information on the histological features of the intestinal tract of japanese quail. The only comprehensive reference is a book published in 1969. This study aims to fill that niche by providing a reference of general histological features of the japanese quail, covering all the main sections of the intestinal tract. Both light and scanning electron microscope(SEM) images are presented. Results showed that the japanese quail intestinal tract is very similar to that of the chicken with the exception of the luminal koilin membrane of the gizzard. Scanning electron microscopic photomicrographs show that in the japanese quail koilin vertical rods are tightly packed together in a uniform manner making a carpet-like appearance. This differs in chicken where the conformations of vertical rods are arranged in clusters.

关键词： japanese quail Coturnix japonica Histology Microscopy Scanning electron microscopy Gastrointestinal tract

Survey of the electrostatic tractor research for reorbiting passive GEO space objects

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Astrodynamics 2018年第4期2卷 291-305页

作者： M.Bengtson K.Wilson j.hughes H.Schaub Aerospace Engineering Sciences Department University of Colorado Boulder431 UCBBoulderCO80309USA

The number of operational satellites and debris objects in the valuable geosynchronous ring has increased steadily over time such that active debris removal missions are necessary to ensure long-term stability. These objects are very large and tumbling, making any mission scenarios requiring physical contact very challenging. In the last 10 years, the concept of using an electrostatic tractor has been investigated extensively. With the electrostatic tractor concept, active charge emission is employed to simultaneously charge the tug or services vehicle, while aiming the charge exhaust onto the passive space debris object to charge it as well. The resulting electrostatic force has been explored to actuate this debris object to a disposal orbit or to detumble the object, all without physical contact. This paper provides a survey of the related research and reviews the charging concepts, the associated electrostatic force and torque modeling, and the feedback control developments, as well as the charge sensing research.

关键词： electrostatics geosynchronous orbit debris control

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Fidel Castro

英语学习 1997年第4期 13-16页

作者： j.hughes

On 1 january,1997,Cuba’s Fidel Castro cele-brates 37 years in *** has survived inva-sion,the collapse of the Soviet Union,US punitivesanctions,and he has outlasted eight Americanpresidents.

关键词： Fidel Castro 卡斯特罗格瓦拉

Evaluation of fatty acid metabolism and innate immunity interactions between commercial broiler, F1 layer × broiler cross and commercial layer strains selected for different growth potentials

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journal of Animal Science and Biotechnology 2018年第1期9卷 156-166页

作者： Nicky-Lee Willson Rebecca E.A.Forder Rick G.Tearle Greg S.Nattrass Robert j.hughes Philip I.Hynd School of Animal and Veterinary Sciences The University of Adelaide The Australian Poultry and Cooperative Research Centre University of New England Davies Research Centre School of Animal and Veterinary SciencesThe University of Adelaide South Australian Research and Development Institute(SARDI) Livestock and Farming Systems South Australian Research and Development Institute(SARDI) Pig and Poultry Production Institute

Background： The broiler industry has undergone intense genetic selection over the past 50 yr. resulting in improvements for growth and feed efficiency, however, significant variation remains for performance and growth traits. Production improvements have been coupled with unfavourable metabolic consequences, including immunological trade-offs for growth, and excess fat deposition. To determine whether interactions between fatty acid（FA） metabolism and innate immunity may be associated with performance variations commonly seen within commercial broiler flocks, total carcass lipid %, carcass and blood FA composition, as wel as genes involved with FA metabolism, immunity and cel ular stress were investigated in male birds of a broiler strain, layer strain and F1 layer × broiler cross at d 14 post hatch. Heterophil：lymphocyte ratios, relative organ weights and bodyweight data were also ***： Broiler bodyweight（n = 12） was four times that of layers（n = 12） by d 14 and had significantly higher carcass fat percentage compared to the cross（n = 6; P = 0.002） and layers（P = 0.017） which were not significantly different from each other（P = 0.523）. The carcass and whole blood FA analysis revealed differences in the FA composition between the three groups indicating altered FA metabolism, despite al being raised on the same diet. Genes associated with FA synthesis andβ-oxidation were upregulated in the broilers compared to the layers indicating a net overal increase in FA metabolism,which may be driven by the larger relative liver size as a percentage of bodyweight in the broilers. Genes involved in innate immunity such as TLR2 and TLR4, as wel as organel e stress indicators ERN1 and XBP1 were found to be nonsignificant, with the exception of high expression levels of XBP1 in layers compared to the cross and broilers. Additional y there was no difference in heterophil： lymphocytes between any of the ***： The results provide evidence that genetic selecti

关键词： Broiler Cel ular stress Fatty acid metabolism Innate immunity Layer Selection

Grass-Root Coaches Knowledge, Understanding, Attitude And Confidence to Deliver Injury Prevention Training in Youth Soccer: a Comparison of Coaches in Three EU Countries

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journal of Science in Sport and Exercise 2020年第4期2卷 367-374页

作者： Mark De Ste Croix F.Ayala S.Hernandez Sanchez M.Lehnert j.hughes School of Sport and Exercise University of GloucestershireCheltenham GL502RHUK Department of Sport Sciences Sport Research CentreMiguel Hernandez University of ElcheElche 03202Spain Department of Pathology and Surgery Physiotherapy Area Miguel Hernandez University of ElcheElche 03202Spain Department of Sport and Physical Culture Palacky UniversityOlomouc 77200Czech Republic

Purpose It is well recognised that injury prevention training can reduce injury incidence,however current coach education pathways do not provide grass-root coaches with the knowledge and confidence to deliver such training to youth *** aim of this study was to explore differences in knowledge,understanding,attitude and confidence to deliver such injury prevention training in three European *** A total of 269 grass-root soccer coaches from 3 European countries(Czech Republic,UK,Spain)were recruited for this study.A validated questionnaire exploring knowledge,understanding,attitude towards and confidence to deliver youth injury prevention training was completed prior to a 2 h workshop on injury prevention *** between countries was examined using Bayesian factors to quantify the evidence for and against the hypothesis of independence(H0)by assuming a Poisson sampling scheme(as there was no a priori restriction on any cell count,nor on the grand total)(BF10 Poisson).Results Current knowledge,attitude and confidence to deliver injury prevention training to youth players was poor across all three European *** few coaches were currently using injury prevention training in their coaching sessions(23%).There were some country specific differences for attitude towards injury prevention training and confidence to deliver injury training,with Spanish coaches reporting a more positive attitude and confidence to deliver such *** fewer coaches in the UK were using injury prevention training compared to coaches in Spain and the Czech *** As coaches identified a need for coach education and few were delivering injury prevention training,there is a clear need to embed and implement this programme into the grassroots coaching framework of sports governing bodies to improve adoption,implementation and maintenance.

关键词： Youth Injury prevention training Coach education Movement competency

Analysis of drying and saturating natural gypsum samples for mechanical testing

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journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 219-227页

作者： Mohammadhossein Sadeghiamirshahidi stanley j.Vitton Department of Civil and Environmental Engineering Michigan Technological University

The stability of underground abandoned gypsum mines is dependent on the gypsum pillar's strength,and most abandoned mines are in a fully saturated condition. Moisture affects the strength of gypsum and is therefore commonly measured when testing rock strength. For most rocks, this is a simple task of weighing the rock's mass before and after oven-heating at a specified temperature and duration. For natural gypsum, however, this is not a straightforward process. Heating natural gypsum can result in dehydration and transformation of gypsum to hemihydrate and anhydrite, thus changing the physical characteristics of the gypsum such as its particle density which in turn affects the moisture content and strength measurements. To prevent transformation when determining the moisture content of gypsum,the American Society for Testing Materials(ASTM) recommends lowering the drying temperature from 110℃ to 60℃ . To investigate the temperature at which gypsum transforms to hemihydrate, we used a helium pycnometer to measure the particle densities of gypsum, hemihydrate and anhydrite. In this research, we suggest that a higher drying temperature of 80℃ can be used for drying gypsum without transforming gypsum to hemihydrate. Further, preparing saturated samples for mechanical testing,which is required in stability analyses of abandoned mines, is challenging due to the dissolution of gypsum when placed in water. To address this problem, we investigated the following methods to saturate gypsum cores taking into account the solubility of gypsum:(1) water immersion,(2) vacuum saturation, and(3) improved vacuum saturation. The research indicates that all the three methods are acceptable but they should be conducted using a saturated gypsum-water solution to minimize dissolution. Further, the research found that the improved vacuum saturation method saturated the test samples within 24 h, while duration of 30 h was required for the other two methods.

关键词： Gypsum-hemihydrate-anhydrite transformation Dehydration Rock core saturation Moisture content Helium pycnometer

Mechanical properties of Michigan Basin’s gypsum before and after saturation

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journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 739-748页

作者： Mohammadhossein Sadeghiamirshahidi stanley j.Vitton Department of Civil and Environmental Engineering Michigan Technological University

The stability analysis of an abandoned underground gypsum mine requires the determination of the mine pillar’s *** is especially important for flooded abandoned mines where the gypsum pillars become saturated and are subjected to dissolution after ***,mine pillars are subjected to blast vibrations that generate some level of macro- and *** samples of gypsum must,therefore,simulate these conditions as close as *** this research,the strength of gypsum is investigated in an as-received saturated condition using uniaxial compressive strength (UCS),Brazilian tensile strength (BTS) and point load index (PLI) *** scale effect was investigated and new correlations were derived to describe the effect of sample size on both UCS and BTS under dry and saturated *** of blasting on these parameters were observed and the importance of choosing the proper samples was ***,correlations were derived for both compressive and tensile strengths under dry and saturated conditions from the PLI test results,which are commonly used as a simple substitute for the indirect determination of UCS and BTS.

关键词： Uniaxial compressive strength (UCS) Brazilian tensile strength (BTS) Point load index (PLI) Scale effect Michigan Basin's gypsum

Intrinsic charm production of doubly charmed baryons:Collider vs. fixed-target

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Science China(Physics,Mechanics & Astronomy) 2020年第2期63卷 29-31页

作者： Ramona Vogt stanley j.Brodsky 无 Nuclear and Chemical Sciences Division Lawrence Livermore National LaboratoryLivermoreCA 94551USA Department of Physics University of CaliforniaDavisCA 95616USA Stanford Linear Accelerator Center Stanford UniversityStanfordCA 94309USA

The LHCb Collaboration has measured the doubly charmed baryon,■^++cc(ucc),through two different decay channels[1,2]in p+p collisions at center-of-mass energies of 7,8 and 13 *** they have performed similar searches for the doubly charmed baryon ■^+cc(dcc),it has not yet been observed by LHCb[3].However,the fixed-target experiment,SELEX,at Fermilab,reported the observation of the ■^+cc in two different decay channels with a 600 GeV charged hyperon beam[4,5].The beam was composed of an admixture of π^±,p,p components as well as the Σ^- *** discussion has arisen over the fact that the fixed-target observations have not been easily reproduced by the collider experiments at higher energies,where one might have expected the production rates to be much higher due to the orders of magnitude increase in the center of mass energy with LHCb.

关键词： doubly fixed decay

A review of methane leakage from abandoned oil and gas wells:A case study in Lubbock,Texas,within the Permian Basin

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Energy Geoscience 2024年第3期5卷 1-12页

作者： stanley U.Opara Chinedu j.Okere Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityTXUSA

In the pursuit of global net zero carbon emissions and climate change mitigation,ongoing research into sustainable energy sources and emission control is *** review examines methane leakage from abandoned oil and gas(AOG)wells,focusing particularly on Lubbock,a geographic area situated within the larger region known as the Permian Basin in West Texas,United *** objective is to assess the extent and environmental implications of methane leakage from these *** analysis integrates pertinent literature,governmental and industry data,and prior Lubbock *** affecting methane leakage,including well integrity,geological characteristics,and human activities,are *** research estimates 1781 drilled wells in Lubbock,forming a foundation for targeted assessments and monitoring due to historical drilling *** hierarchy of well statuses in Lubbock highlights the prevalence of“active oil wells,”trailed by“plugged and abandoned oil wells”and“inactive oil wells.”Methane leakage potential aligns with these well types,underscoring the importance of strategic monitoring and *** analysis notes a zenith in“drilled and completed”wells during *** our study's case analysis and literature review reiterate the critical significance of assessing and mitigating methane emissions from AOG wells,it's important to clarify that the research does not directly provide methane leakage ***,it contextualizes the issue's magnitude and emphasizes the well type and status analysis's role in targeted mitigation *** summary,our research deepens our understanding of methane leakage,aiding informed decision-making and policy formulation for environmental *** clarifying well type implications and historical drilling patterns,we aim to contribute to effective strategies in mitigating methane emissions from AOG wells.

关键词： Net zero carbon emissions Climate change mitigation Methane emission control Abandoned oil and gas(AOG)well Permian Basin