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Computational fluid dynamics simulation on the longwall gob breathing

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International Journal of Mining Science and Technology 2017年第2期27卷 185-189页

作者： Samuel A.Lolon Jürgen F.Brune gregory E.Bogin Jr. John w.Grubb Saqib A.Saki Aditya Juganda Department of Mining Engineering Colorado School of MinesCO 80401USA Department of Mechanical Engineering Colorado School of Mines CO 80401USA

In longwall mines, atmospheric pressure fluctuations can disturb the pressure balance between the gob and the ventilated working area, resulting in a phenomenon known as ‘‘gob breathing". Gob breathing triggers gas flows across the gob and the working areas and may result in a condition where an oxygen deficient mixture or a methane accumulation in the gob flows into the face area. Computational Fluid Dynamics(CFDs) modeling was carried out to analyze this phenomenon and its impact on the development of an explosive mixture in a bleeder-ventilated panel scheme. Simulation results indicate that the outgassing and ingassing across the gob and the formation of Explosive Gas Zones(EGZs) are directly affected by atmospheric pressure changes. In the location where methane zones interface with mine air, EGZ fringes may form along the face and in the bleeder entries. These findings help assess the methane ignition and explosion risks associated with fluctuating atmospheric pressures.

关键词： CFDs Gob breathing barometric pressure Explosive gas zone Longwall mine Methane explosion

Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep

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Journal of Animal Science and Biotechnology 2018年第2期9卷 306-318页

作者： Yasser Y.Lenis gregory A.Johnson Xiaoqiu wang wendy w.Tang Kathrin A.Dunlap M.Carey Satterfield Guoyao wu Thomas R.Hansen Fuller w.Bazer Department of Animal Science Texas A&M UniversityCollege StationTX 77843-2471USA Center for Animal Biotechnology and Genomics Texas A&M UniversityCollege StationTX 77843USA Centauro Research Group School of Veterinary MedicineFaculty of Agrarian ScienceUniversidad de AntioquiaCalle 70 No52-21 MedellínColombia Faculty of Agricultural Sciences Calle 222 No.55-37UDCABogotaColombia Present address:National Institute of Environmental Health Sciences Research Triangle ParkNC 27709USA Animal Reproduction and Biotechnology Laboratory Department of Biomedical SciencesCollege of Veterinary Medicine and Biomedical SciencesColorado State UniversityFort CollinsCO 80523USA

Background: Polyamines stimulate DNA transcription and m RNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and survival of conceptuses(embryo/fetus and placenta). The ovine conceptus produces polyamines via classical and non-classical pathways. In the classical pathway, arginine(Arg) is transformed into ornithine, which is then decarboxylated by ornithine decarboxylase(ODC1) to produce putrescine which is the substrate for the production of spermidine and spermine. In the non-classical pathway, Arg is converted to agmatine(Agm) by arginine decarboxylase(ADC), and Agm is converted to putrescine by agmatinase(AGMAT).Methods: Morpholino antisense oligonucleotides(MAOs) were designed and synthesized to inhibit translational initiation of the m RNAs for ODC1 and ADC, in ovine ***: The morphologies of MAO control, MAO-ODC1, and MAO-ADC conceptuses were normal. Double knockdown of ODC1 and ADC(MAO-ODC1:ADC) resulted in two phenotypes of conceptuses; 33% of conceptuses appeared to be morphological y and functional y normal(phenotype a) and 67% of the conceptuses presented an abnormal morphology and functionality(phenotype b). Furthermore, MAO-ODC1:ADC(a) conceptuses had greater tissue concentrations of Agm,putrescine, and spermidine than MAO control conceptuses, while MAO-ODC1:ADC(b) conceptuses only had greater tissue concentrations of Agm. Uterine flushes from ewes with MAO-ODC1:ADC(a) had greater amounts of arginine, aspartate, tyrosine, citrulline, lysine, phenylalanine, isoleucine, leucine, and glutamine, while uterine flushes of ewes with MAO-ODC1:ADC(b) conceptuses had lower amount of putrescine, spermidine, spermine, alanine, aspartate,glutamine, tyrosine, phenylalanine, isoleucine, leucine, and ***: The double-knockdown of translation of ODC1 and ADC m RNAs was most detrimental to conceptus development and their production of int

关键词： Agmatine Arginine Interferon tau Polyamines Trophectoderm cells

Noninvasive ventilation for pediatric interfacility transports:a retrospective study

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world Journal of Pediatrics 2020年第4期16卷 422-425页

作者： Samantha Holbird Tanya Holt Adam Shaw gregory Hansen College of Medicine University of SaskatchewanSaskatoonSKCanada Division of Pediatric Critical Care Jim Pattison Children’s Hospital103 Hospital DriveSaskatoonSKS7N 0W8Canada

Background To characterize pediatric patients supported with continuous positive airway pressure and bilevel positive airway pressure(CPAP/BiPAP)or high-flow nasal cannula(HFNC)during interfacility transport(IFT).Methods A retrospective study with a provincial pediatric transport team from a tertiary hospital pediatric intensive care *** patients aged 28 days towho required IFT between January 2017 and December 2018,were identified through a transport registry and were included in the *** A total of 118(26.7%)patients received CPAP/BIPAP or HFNC support for *** most common respiratory diagnosis was bronchiolitis(46%).These patients were placed on respiratory support,31.4 minutes after the transport team’s *** required intubation during their IFT,despite mean transport times of 163 *** This study may provide important information for programs with large catchment areas,in which large distances and transport times should not be barriers to NIV implementation.

关键词： Children Critical illness Intubation Noninvasive ventilation Transportation of patients

Dietary supplementation with 0.4%L-arginine between days 14 and 30 of gestation enhances NO and polyamine syntheses and water transport in porcine placentae

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Journal of Animal Science and Biotechnology 2023年第2期14卷 627-639页

作者： Cassandra M.Herring Fuller w.Bazer gregory A.Johnson Heewon Seo Shengdi Hu Mohammed Elmetwally wenliang He Daniel B.Long Guoyao wu Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA Department of Veterinary Integrative Biosciences Texas A&M UniversityCollege StationTX 77843USA.

Background:Most embryonic loss in pigs occurs before d 30 of *** supplementation with L-arginine(Arg) during early gestation can enhance the survival and development of conceptuses(embryo/fetus and its extraembryonic membranes) in ***,the underlying mechanisms remain largely ***:Between d 14 and 30 of gestation,each gilt was fed daily 2 kg of a corn-and soybean-meal based diet(12% crude protein) supplemented with either 0.4% Arg(as Arg-HCl) or an isonitrogenous amount of L-alanine(Control).There were 10 gilts per treatment *** d 30 of gestation,gilts were fed either Arg-HCl or L-alanine 30 min before they were hysterectomized,followed by the collection of placentae,embryos,fetal membranes,and fetal *** and allantoic fluids were analyzed for nitrite and nitrate [NOx;stable oxidation products of nitric oxide(NO)],polyamines,and amino *** were analyzed for syntheses of NO and polyamines,water and amino acid transport,concentrations of amino acid-related metabolites,and the expression of angiogenic factors and aquaporins(AQPs).Results:Compared to the control group,Arg supplementation increased(P weight(+ 36.5%),the total weight of viable fetuses(+ 33.5%),fetal crown-to-rump length(+ 4.7%),and total allantoic and amniotic fluid volumes(+ 44.6% and + 75.5% respectively).Compared to control gilts,Arg supplementation increased(P < 0.05) placental activities of GTP cyclohydrolase-1(+ 33.1%) and ornithine decarboxylase(+ 29.3%);placental syntheses of NO(+ 26.2%) and polyamines(+ 28.9%);placental concentrations of NOx(+ 22.5%),tetrahydrobiopterin(+ 21.1%),polyamines(+ 20.4%),c AMP(+ 27.7%),and c GMP(+ 24.7%);total amounts of NOx(+ 61.7% to + 96.8%),polyamines(+ 60.7% to + 88.7%),amino acids(+ 39% to + 118%),glucose(+ 60.5% to + 62.6

关键词： Angiogenesis Arginine Fetus Placenta Reproduction

Spherical Parameterization of Marching Cubes IsoSurfaces Based upon Nearest Neighbor Coordinates

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Journal of Computer Science & Technology 2009年第1期24卷 30-38页

作者： gregory M.Nielson 张丽艳李建黄辉扬 Arizona State University TempeAZU.S.A. Nanjing University of Aeronautics and Astronautics Handong Global University National Central University

we present some new methods for parameterizing the triangle mesh surface （TMS） which result from the Marching Cubes （MC） algorithm. The methods apply to surfaces of genus zero and the parameter domain is a unit sphere. we take advantage of some special properties of the TMS resulting from the MC algorithm to obtain simple, computational efficient representations of the nearest neighbor coordinates and utilize these coordinates in the characterization of the parameterization by means of systems of equations which are solved iteratively. Examples and comparisons are presented.

关键词： isosurface marching cubes mapping parameterization spherical triangle mesh surface

Paramyxovirus evasion of innate immunity: Diverse strategies for common targets

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world Journal of Virology 2013年第2期2卷 57-70页

作者： Michelle D Audsley gregory w Moseley Department of Biochemistry and Molecular Biology Monash University

The paramyxoviruses are a family of > 30 viruses that variously infect humans, other mammals and fish to cause diverse outcomes, ranging from asymptomatic to lethal disease, with the zoonotic paramyxoviruses Nipah and Hendra showing up to 70% case-fatality rate in humans. The capacity to evade host immunity is central to viral infection, and paramyxoviruses have evolved multiple strategies to overcome the host interferon(IFN)-mediated innate immune response through the activity of their IFN-antagonist proteins. Although paramyxovirus IFN antagonists generally target common factors of the IFN system, including melanoma differentiation associated factor 5, retinoic acid-inducible gene-I, signal transducers and activators of transcription(STAT)1 and STAT2, and IFN regulatory factor 3, the mechanisms of antagonism show remarkable diversity between different genera and even individual members of the same genus; the reasons for this diversity, however, are not currently understood. Here, we review the IFN antagonism strategies of paramyxoviruses, highlighting mechanistic differences observed between individual species and genera. we also discuss potential sources of this diversity, including biological differences in the host and/or tissue specificity of different paramyxoviruses, and potential effects of experimental approaches that have largely relied on in vitrosystems. Importantly, recent studies using recombinant virus systems and animal infection models are beginning to clarify the importance of certain mechanisms of IFN antagonism to in vivo infections, providing important indications not only of their critical importance to virulence, but also of their potential targeting for new therapeutic/vaccine approaches.

关键词： Paramyxoviridae Innate immunity Signal transducers and activators of transcription 1 Signal transducers and activators of transcription 2 Melanoma differentiation associated factor 5 Retinoic acid-inducible gene-I

Carotid Intima-media Thickness Measurements： Relations with Atherosclerosis, Risk of Cardiovascular Disease and Application in Randomized Controlled Trials

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Chinese Medical Journal 2016年第2期129卷 215-226页

作者： Michiel L Bots gregory w Evans Charles H Tegeler Rudy Meijer Julius Center for Health Sciences and Primary Care University Medical Center Utrecht Utrecht The Netherlands Department of Biostatistical Sciences and Neurology Wake Forest School of Medicine Winston-Salem NC USA Department of Neuiology Ward A Riley Ultrasound Center Wake Forest School of Medicine Medical Center Boulevard Winston-Salem NC USA

Cardiovascular disease （CVD） is the leading cause of death worldwide and contributes considerably to morbidity The underlying cause is atherosclerosisThe development of new preventive therapies is one of the steps to control the CVD epidemic. It is increasingly demanded that promising therapies be evaluated in trials using cardiovascular （CV） morbidity and mortality （M and M） as a primary outcome.

关键词： Atherosclerosis Cardiovascular Disease Prevention Trials

Pectin May Hinder the Unfolding of Xyloglucan Chains during Cell Deformation： Implications of the Mechanical Performance of Arabidopsis Hypocotyls with Pectin Alterations

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Molecular Plant 2009年第5期2卷 990-999页

作者： willie Abasolo Michaela Eder Kazuchika Yamauchi Nicolai Obel Antje Reinecke Lutz Neumetzler John w.C. Dunlop gregory Mouille Markus Pauly Herman Hofte Ingo Burgert Max-Planck-lnstitute of Colloids and Interfaces Department of Biomaterials Potsdam Germany College of Forestry and Natural Resources University of the Philippines Los Banos Philippines Department of Socio-Environmental Energy Science Kyoto University Japan Max-Planck-lnstitute for Molecular Plant Physiology Potsdam Germany Laboratoire de Biologie Cellulaire UR501 Institute Jean-Pierre Bourgin INRA Versailles France Michigan State University Plant Research Laboratory East Lansing Michigan USA

Plant cell walls, like a multitude of other biological materials, are natural fiber-reinforced composite materials. Their mechanical properties are highly dependent on the interplay of the stiff fibrous phase and the soft matrix phase and on the matrix deformation itself. Using specific Arabidopsis thaliana mutants, we studied the mechanical role of the matrix assembly in primary cell walls of hypocotyls with altered xyloglucan and pectin composition. Standard microtensile tests and cyclic loading protocols were performed on tour1 hypocotyls with affected RGII borate diester cross-links and a hindered xyloglucan fucosylation as well as qua2 exhibiting 50% less homogalacturonan in comparison to wild-type. As a control, wild-type plants （Col-0） and mur2 exhibiting a specific xyloglucan fucosylation and no differences in the pectin network were utilized. In the standard tensile tests, the ultimate stress levels （-tensile strength） of the hypocotyls of the mutants with pectin alterations （mur1, qua2） were rather unaffected, whereas their tensile stiffness was noticeably reduced in comparison to Col-0. The cyclic loading tests indicated a stiffening of all hypocotyls after the first cycle and a plastic deformation during the first straining, the degree of which, however, was much higher for tour1 and qua2 hypocotyls. Based on the mechanical data and current cell wall models, it is assumed that folded xyloglucan chains between cellulose fibrils may tend to unfold during straining of the hypocotyls. This response is probably hindered by geometrical constraints due to pectin rigidity.

关键词： Arabidopsis thaliana mutants cellulose xyloglucan pectin cyclic loading tests.

Methylprednisolone for acute spinal cord injury: an increasingly philosophical debate

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Neural Regeneration Research 2016年第6期11卷 882-885页

作者： Christian A.Bowers Bornali Kundu gregory w.J.Hawryluk Department of Neurosurgery Clinical Neurosciences Center University of Utah

Following publication of NASCIS Ⅱ, methylprednisolone sodium succinate（MPSS） was hailed as a breakthrough for patients with acute spinal cord injury（SCI）. MPSS use for SCI has since become very controversial and it is our opinion that additional evidence is unlikely to break the stalemate amongst clinicians. Patient opinion has the potential to break this stalemate and we review our recent findings which reported that spinal cord injured patients informed of the risks and benefits of MPSS reported a preference for MPSS administration. we discuss the implications of the current MPSS debate on translational research and seek to address some misconceptions which have evolved. As science has failed to resolve the MPSS debate we argue that the debate is an increasingly philosophical one. we question whether SCI might be viewed as a serious condition like cancer where serious side effects of therapeutics are tolerated even when benefits may be small. we also draw attention to the similarity between the side effects of MPSS and isotretinoin which is prescribed for the cosmetic disorder acne vulgaris. Ultimately we question how patient autonomy should be weighed in the context of current SCI guidelines and MPSS＇s status as a historical standard of care.

关键词： debate autonomy opinion argue break informed administration translational historical preference