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Exotic parrots breeding in urban tree cavities: nesting requirements, geographic distribution, and potential impacts on cavity nesting birds in southeast Florida

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Avian Research 2019年第4期10卷 459-468页

作者： Joshua M.Diamond Michael s.Ross Florida International University Earth & Environment

Background:Exotic parrots have established breeding populations in southeast Florida,including several species that nest in tree *** aimed to determine the species identity,nest site requirements,relative nest abundance,geographic distribution,and interactions of parrots with native cavity-nesting bird ***:We searched Miami-Dade County,Florida,and nearby areas for natural cavities and holes excavated by woodpeckers,recording attributes of potential nest *** inspected all cavities with an elevated video inspection system to determine occupancy by parrots or other *** mapped nearly 4000 citizen science observations of parrots in our study area corresponding to our study period,and used these to construct range maps,comparing them to our nesting ***:Not all parrots reported or observed in our study area were actively *** parrots were observed at tree cavities,which previous studies have suggested is evidence of reproduction,but our inspections with an elevated video inspection system suggest they never initiated nesting *** parrot species did successfully nest in tree cavities,Red-masked Parakeets(Psittacara erythrogenys)and Orange-winged Parrots(Amazona amazonica)being the most common(n=7 and 6 nests,respectively).These two parrots had similar nesting requirements,but Orange-winged Parrots use nests with larger entrance holes,which they often *** analysis of nests combined with citizen science data indicate that parrots are limited to developed *** most common parrots were less abundant cavity nesters than the native birds which persist in Miami’s urban areas,and far less abundant than the invasive European starling(sturnus vulgaris).Conclusions:Exotic parrots breeding elsewhere in the world have harmed native cavity-nesting birds through interference competition,but competitive interference in southeast Florida is minimized by the urban affinities of parrots in this ***

关键词： Amazona Cavity nest webs Invasive species Parakeets Psittacara Urban ecology

The impact of gate misalignment on the analog performance of a dual-material double gate junctionless transistor

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Journal of semiconductors 2015年第9期36卷 47-53页

作者： s.Intekhab Amin R.K.sarin Department of Electronics and Communication Engineering Dr.B.R.Ambedkar National Institute of Technology Jalandhar

The analog performance of gate misaligned dual material double gate junctionless transistor is demonstrated for the first time. The cases considered are where misalignment occurs towards source side and towards drain side. The analog performance parameters analyzed are： transconductance, output conductance, intrinsic gain and cut-off frequency. These figures of merits （FOMs） are compared with a dual material double gate inversion mode transistor under same gate misalignment condition. The impacts of different length of control gate （L 1） for a given gate length （L） are also studied and the optimum lengths La under misalignment condition to have better analog FOMs and high tolerance to misalignment are presented.

关键词： dual material double gate (DMDG) junctionless transistor inversion mode transistor gate misalign-ment analog FOMs

Conservation form of Helbing's fluid dynamic traffic flow model

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Applied Mathematics and Mechanics(English Edition) 2011年第9期32卷 1109-1118页

作者：李书峰张鹏 s.C.WONG shanghai Institute of Applied Mathematics and Mechanics Shanghai University shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University Department of Civil Engineering The University of Hong Kong

A standard conservation form is derived in this *** hyperbolicity of Helbing＇s fluid dynamic traffic flow model is proved,which is essential to the general analytical and numerical study of this *** the basis of this conservation form,a local discontinuous Galerkin scheme is designed to solve the resulting system *** evolution of an unstable equilibrium traffic state leading to a stable stop-and-go traveling wave is *** simulation also verifies that the model is truly improved by the introduction of the modified diffusion coefficients,and thus helps to protect vehicles from collisions and avoide the appearance of the extremely large density.

关键词： conservation form hyperbolicity local discontinuous Galerkin method stop-and-go wave

Genome Editing:From Drosophila to Non-Model Insects and Beyond

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Journal of Genetics and Genomics 2016年第5期43卷 263-272页

作者： Yueping Huang Zhiping Liu Yikang s.Rong Institute of Entomology School of Life SciencesSun Yat-sen University

Insect is the largest group of animals on *** insect species inflict economical and health losses to *** many more benefit us by helping to maintain balances in our *** benefits that insects offer remain largely untapped,justifying our continuing efforts to develop tools to better understand their biology and to better manage their *** we focus on reviewing the progresses made in the development of genome engineering tools for model *** of detailed descriptions of the molecular mechanisms underlying each technical advance,we focus our discussion on the logistics for implementing similar tools in non-model *** none of the tools were developed specific for insects,similar approaches can be applied to other non-model organisms.

关键词： Insect transgenesis Drosophila Black soldier fly Gene targeting site-specific recombination Piggybac transposon

Use of gene-editing technology to introduce targeted modifications in pigs

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Journal of Animal science and Biotechnology 2018年第2期9卷 268-277页

作者： Junghyun Ryu Randall s.Prather Kiho Lee Department of Animal and Poultry sciences Virginia Tech175 W.Campus DriveBlacksburgVA 24061USA Division of Animal science University of Missouri-Columbia920 East Campus DriveColumbiaMO 65211USA National swine Resource and Research Center University of Missouri-ColumbiaColumbiaMO 65211USA

Pigs are an important resource in agriculture and serve as a model for human diseases. Due to their physiological and anatomical similarities with humans, pigs can recapitulate symptoms of human diseases, making them a useful model in biomedicine. However, in the past pig models have not been widely used partially because of the difficulty in genetic modification. The lack of true embryonic stem cells in pigs forced researchers to utilize genetic modification in somatic cells and somatic cell nuclear transfer(sCNT) to generate genetically engineered(GE) pigs carrying site-specific modifications. Although possible, this approach is extremely inefficient and GE pigs born through this method often presented developmental defects associated with the cloning process. Advancement in the gene-editing systems such as Zinc-Finger Nucleases(ZFNs), Transcription activator-like effector nucleases(TALENs), and the Clustered regularly interspaced short palindromic repeat(CRIsPR)/CRIsPR-associated 9(Cas9) system have dramatically increased the efficiency of producing GE pigs. These gene-editing systems, specifically engineered endonucleases, are based on inducing double-stranded breaks(DsBs) at a specific location, and then site-specific modifications can be introduced through one of the two DNA repair pathways: non-homologous end joining(NHEJ) or homology direct repair(HDR).Random insertions or deletions(indels) can be introduced through NHEJ and specific nucleotide sequences can be introduced through HDR, if donor DNA is provided. Use of these engineered endonucleases provides a higher success in genetic modifications, multiallelic modification of the genome, and an opportunity to introduce site-specific modifications during embryogenesis, thus bypassing the need of sCNT in GE pig production. This review will provide a historical prospective of GE pig production and examples of how the gene-editing system, led by engineered endonucleases, have improved GE pig production. We wil

关键词： CRIsPR/Cas9 Gene-editing Genetic engineering Knock-in Knockout Pig TALEN ZFN

Assessment of strain bursting in deep tunnelling by using the finite-discrete element method

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 12-37页

作者： Ioannis Vazaios Mark s.Diederichs Nicholas Vlachopoulos Department of Ceological saences and Ceological Engineering Queen's UniversityKingstonCanada

Rockbursting in deep tunnelling is a complex phenomenon posing significant challenges both at the design and construction stages of an underground excavation within hard rock masses and under high in situ stresses. While local experience, field monitoring, and informed data-rich analysis are some of the tools commonly used to manage the hazards and the associated risks, advanced numerical techniques based on discontinuum modelling have also shown potential in assisting in the assessment of rockbursting. In this study, the hybrid finite-discrete element method(FDEM) is employed to investigate the failure and fracturing processes, and the mechanisms of energy storage and rapid release resulting in bursting, as well as to assess its utility as part of the design process of underground *** the calibration of the numerical model to simulate a deep excavation in a hard, massive rock mass, discrete fracture network(DFN) geometries are integrated into the model in order to examine the impact of rock structure on rockbursting under high in situ stresses. The obtained analysis results not only highlight the importance of explicitly simulating pre-existing joints within the model, as they affect the mobilised failure mechanisms and the intensity of strain bursting phenomena, but also show how the employed joint network geometry, the field stress conditions, and their interaction influence the extent and depth of the excavation induced damage. Furthermore, a rigorous analysis of the mass and velocity of the ejected rock blocks and comparison of the obtained data with well-established semi-empirical approaches demonstrate the potential of the method to provide realistic estimates of the kinetic energy released during bursting for determining the energy support demand.

关键词： Rockburst Finite-discrete element method(FDEM) Deep tunnelling Hard rock excavations Brittle fracturing Discrete fracture network(DFN)

Improved Osteointegration of Ti-6Al-4V-implants of Different surface Texture by the Use of Bone Morphogenetic Protein-3 (BMP-3)

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Journal of Wuhan University of Technology(Materials science) 2005年第B12期20卷 301-303页

作者： Esenwein s A Esenwein s Herr G Hauser J Muhr G Hartwig C-H Department of surgery BG Trauma Center Bergmannsheil University Hospital Buerkle-de-la-Camp-Platz 1 D-44789 Bochum Germany Dental Practice Am Obstmarkt 5 D-71522 Backnang Germany Advanced Tissue Regeneration GmbH Turmstr. 16 D-35578 Wetzlar Germany Department of Orthopaedics Michaelis-Hospital Eichenstrasse 34 D-20244 Hamburg Germany

Half of altogether 60 cylindrical implant devices made of titanium-aluminum-vanadium alloy （ Ti-6Al-4V） were plusna-sprayed with a hydroxyapatite-couting and the other half had a corundum blasted porous surface. 15 implants of each group of the titanium test buplants were coated with 230 μg porcine, high-purified BMP- 3-precipitute per implant. In each case a BMP- 3-couted and an uncoated control-device were implanted into the femoral part of the putellofemoral joint of the right and left leg of 30 adult giant rabbits. Histomorphological and histomorphometrical we found in both groups with BMP- 3-coated test devices an improved osteointegrution. stutistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of tony formed bone of the BMP- 3-coated corundum- blasted or hydroxyapathe- coated Ti- 6Al- 4 V test devices compared to the non-couted controls of the same t）pe （p 〈 0.01, t-test for matched samples）. In both implant groups with BMP-couting a synergetic effect was verifiable although the bone ongrowth in the hydroxyaputite coated implants was more extensive than in the corundum blasted implants. Light microscopy demonstrated osteointegrution without connective tissue membrane around the surface of the implants. Our results indicate that composite metal implants,as used in endoprosthetics and implantology , are suitable carriers for BMP- 3 and im proved fixation of the implants can be achieved. The hydroxyapatite surface is superior to the corundum-blasted surface with regards to the observed parameters because of its pronounced bioactivity and its osteoconductive characteristics.

关键词： bone morphogenetic protein-3 BMP- 3 hydroxyapatite osteointegration surface coating bone ingrowth implantology

shear strength Evaluation of Concrete Beams Reinforced with BFRP Bars and steel Fibers without stirrups

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Computers, Materials & Continua 2016年第2期51卷 81-103页

作者： smitha Gopinath s.Meenu A.Ramachandra Murthy scientist.CsIR-structural Engineering Research Centre Chennai 600113India Project student CSIR-Structural Engineering Research CentreChennai 600113India

This paper presents experimental and analytical investigations on concrete beams reinforced with basalt fiber reinforced polymer(BFRP)and steel fibers without *** behaviour of BFRP reinforced beams and steel fiber reinforced beams were evaluated and the effect of combining BFRP bars and steel fiber was investigated in *** is found that combining s teel fibers with BFRP could change the shear failure of BFRP reinforced beam to flexural ***,the existing analytical models were reviewed and compared to predict the shear strength of both FRP reinforced and steel fiber reinforced *** on the review,the appropriate model was chosen and modified to predict the shear strength of BFRP reinforced beam along with steel fibers.

关键词： Basalt fiber reinforced polymer(BFRP) steel fibers Flexure,shear strength

study on performance of a packed bed latent heat thermal energy storage unit integrated with solar water heating system

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2006年第8期7卷 1422-1430页

作者： NALLUsAMY N sAMPATH s. VELRAJ R. Department of Mechanical Engineering Sri Venkateswara College of Engineering Chennai 602 105 India Department of Automobile Engineering Sri Venkateswara College of Engineering Chennai 602 105 India Institute for Energy studies College of Engineering Guindy Anna University Chennai 600 025 India

In thermal systems such as solar thermal and waste heat recovery systems, the available energy supply does not usually coincide in time with the process demand. Hence some form of thermal energy storage (TEs) is necessary for the most effective utilization of the energy source. This study deals with the experimental evaluation of thermal performance of a packed bed latent heat TEs unit integrated with solar flat plate collector. The TEs unit contains paraffin as phase change material (PCM) filled in spherical capsules, which are packed in an insulated cylindrical storage tank. The water used as heat transfer fluid (HTF) to transfer heat from the solar collector to the storage tank also acts as sensible heat storage material. Charging experiments were carried out at varying inlet fluid temperatures to examine the effects of porosity and HTF flow rate on the storage unit performance. The performance parameters such as instantaneous heat stored, cumulative heat stored, charging rate and system efficiency are studied. Discharging experiments were carried out by both continuous and batchwise processes to recover the stored heat, and the results are presented.

关键词： Charging Discharging Heat transfer fluid (HTF) Latent heat Phase change material (PCM) Packed bed Thermalenergy storage (TEs)