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On sustaining the ecology and livestock industry of the Bayanbuluk Grasslands

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journal of Arid Land 2010年第1期2卷 57-63页

作者： Adrian R williams Pendragon Dryland Management services

A short visit to the Bayanbuluk Grassland in the Tianshan Mountains, Xinjiang, PRC, revealed a number of environmental and livestock production problems, including grassland degradation, loss of grassland biodiversity, soil erosion and flash flooding downstream, decreased pasture productivity, and poor livestock nutrition (especially in winter) leading to stock losses and flocks and herds of low productivity. This paper describes those problems and then suggests some solutions. short duration, high intensity grazing could be one of the solutions to both improving grassland condition and improving livestock nutrition. Local production of fodder crops for feeding in winter and spring deserves testing, using adapted strains of Alfalfa (Medicago sativa) and trialling fodder root crop production. It is important to realise that the land management objectives of scientists, administrators, herders and farmers may be similar, and that there are opportunities for land improvement through working together.

关键词： Bayanbuluk Grasslands Tianshan Mountains reversing grassland degradation improving livestock productivity

Perforated duodenal ulcer:An unusual manifestation of allergic eosinophilic gastroenteritis

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World journal of Gastroenterology 2015年第44期21卷 12709-12712页

作者： Kevin M Riggle Ghassan Wahbeh Elizabeth M williams Kimberly j Riehle Department of General surgery University of Washington Seattle Division of Gastroenterology Seattle Children’s Hospital Seattle Division of Pathology Seattle Children’s Hospital Seattle Division of Pediatric General and Thoracic surgery Seattle Children’s Hospital

spontaneous perforation of a duodenal ulcer secondary to allergic eosinophilic gastroenteritis(EGE) has not been previously reported. We present such a case in a teenager who presented with peritonitis. After exploration and operative repair of his ulcer, he continued to experience intermittent abdominal pain, and further evaluation revealed eosinophilic gastroenteritis in the setting of multiple food allergies. His EGE resolved after adhering to a restrictive diet. Both duodenal ulcers and EGE are very rarely seen in pediatric patients. EGE has a variable presentation depending on the layer(s) of bowel wall affected and the segment of the gastrointestinal tract that is involved. Once diagnosed, it may respond to dietary changes in patients with recognized food allergies, or to steroids in patients in whom an underlying cause is not identified. Our case highlights the need to keep EGE in the differential diagnosis when treating pediatric patients with duodenal ulcers. The epidemiology, pathophysiology, and treatment of EGE are also discussed, along with a review of the current literature.

关键词： Pediatric Duodenal ulcer Eosinophilic Gastroenteri

Combining X-ray microtomography with computer simulation for analysis of granular and porous materials

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Particuology 2010年第2期8卷 81-99页

作者： Roberto Moreno-Atanasio Richard A. williams Institute of Particle science and Engineering School of Process Environmental and Materials Engineering University of Leeds Leeds LS2 9JT UK

The use of X-ray microtomographic （XMT） methods in analysing particulate systems has expanded rapidly in recent years with the availability of affordable desk-top apparatus. This review presents a summary of the major applications in which computer simulations are explicitly coupled with XMT in the area of granular and porous materials. We envisage two main ways of establishing the coupling between both techniques, based on the transference or exchange of information by using physical or geometrical parameters （i.e. a parametric link through fitting to a process model） or through the direct use of3D XMT digital images （i.e. comparing image pixels and features directly）. Examples of coupled applications are shown for the study of transport properties of rocks, particle packing, mechanical loading and sintering. Often, the link between XMT and computer simulations is based on visual comparisons and we conclude that the use of quantitative parameters such as the number of interparticle contacts, force networks or granule shape to link both techniques is still underrepresented in the literature. strategies to provide a more robust and quantitative approach to optimise the information obtained from such tomography analyses are proposed. 2010 Chinese society of Particuology and Institute of Process Engineering, Chinese Academy of sciences. Published by Elsevier B.V. All rights reserved.

关键词： X-ray microtomographyGranular flowComputer modellingLattice Boltzmann methodDiscrete element method

small extrachromosomal circular DNA in amyotrophic lateral sclerosis matter

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Neural Regeneration Research 2025年第5期20卷 1411-1413页

作者： Marcos j.Arauzo-Bravo Daniela Gerovska Matthias schwab Alexandra Kretz Computational Biology and systems Biomedicine Biodonostia Health Research InstituteSan SebastianSpain Basque Foundation for science IKERBASQUEBilbaoSpainMax Planck Institute for Molecular BiomedicineComputational Biology and Bioinformatics GroupMünsterNorth Rhine-WestphaliaGermany Department of Cell Biology and Histology Faculty of Medicine and NursingUniversity of Basque Country(UPV/EHU)LeioaSpain Department of Neurology Jena University HospitalJenaThuringiaGermany

Comprehensive studies identify motor neuron spectrum disorders including amyotrophic lateral sclerosis(ALs)as globally rising fatal disorders with the highest prevalence in aging populations,influenced by ethnicity and ancestry(GBD 2016 Motor Neuron Disease Colla borators,2018).While~10% of diagnoses involve a family history(fALs),most cases are considered sporadic(sALs).However,population-based studies suggest that even cases without a common index mutation impart heritability(Ryan et al.,2019),indicating a crucial role of rare and as yet unknown genetic denominators.

关键词： amyotrophic sclerosis

Invertebrate Iridovirus Modulation of Apoptosis

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Virologica sinica 2009年第4期24卷 295-304页

作者： Trevor williams Nilesh s. Chitnis shn L. Bilimoria Instituto de Ecología AC Abramson Cancer Center and Department of Cancer Biology University of Pennsylvania Department of Biological sciences The Center for Biotechnology and Genomics Texas Tech University

Programmed cell death （apoptosis） is a key host response to virus infection. Viruses that can modulate host apoptotic responses are likely to gain important opportunities for transmission. Here we review recent studies that demonstrate that particles of Invertebrate iridescent virus 6 （IIV-6）（Iridoviridae, genus Iridovirus）, or an IIV-6 virion protein extract, are capable of inducing apoptosis in lepidopteran and coleopteran cells, at concentrations 1000-fold lower than that required to shut-off host macromolecular synthesis. Induction of apoptosis depends on endocytosis of one or more heat-sensitive virion component（s）. studies with a jNK inhibitor （sP600125） indicated that the jNK signaling pathway is significantly involved in apoptosis in IIV-6 infections of Choristoneurafumiferana cells. The genome of IIV-6 codes for an inhibitor of apoptosis iap gene （193R） that encodes a protein of 208 aa with 15% identity and 28% similarity in its amino acid sequence to IAP-3 from Cydia pomonella ganulovirus （CpGV）. Transcription of IIV-6 iap did not require prior DNA or protein synthesis, indicating that it is an immediate-early class gene. Transient expression and gene knockdown studies have confirmed the functional nature of the IIV-6 lap gene. We present a tentative model for IIV-6 induction and inhibition of apoptosis in insect cells and discuss the potential applications of these findings in insect pest control.

关键词： Apoptosis Invertebrate iridescent virus 6 Induction by endocytosis Inhibition of apoptosis (iap) gene Iridoviridae jNK pathway involvement.

solution of shallow-water equations using least-squares finite-element method

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Acta Mechanica sinica 2008年第5期24卷 523-532页

作者： s.j. Liang j,-H, Tang M.-s. Wu Department of Marine Environmental Informatics National Taiwan Ocean UniversityKeelung 20224 Taiwan China Department of Bioenvironmental Engineering Chung-Yuan Christian University Chung-Li 32023 Taiwan China Department of Geographic Information systems Feng Chia University Taichung 40724 Taiwan China

A least-squares finite-element method （LsFEM） for the non-conservative shallow-water equations is presented. The model is capable of handling complex topography, steady and unsteady flows, subcritical and supercritical flows, and flows with smooth and sharp gradient changes. Advantages of the model include：（1） sources terms, such as the bottom slope, surface stresses and bed frictions, can be treated easily without any special treatment; （2） upwind scheme is no needed; （3） a single approximating space can be used for all variables, and its choice of approximating space is not subject to the Ladyzhenskaya-Babuska-Brezzi （LBB） condition; and （4） the resulting system of equations is symmetric and positive-definite （sPD） which can be solved efficiently with the preconditioned conjugate gradient method. The model is verified with flow over a bump, tide induced flow, and dam-break. Computed results are compared with analytic solutions or other numerical results, and show the model is conservative and accurate. The model is then used to simulate flow past a circular cylinder. Important flow charac-teristics, such as variation of water surface around the cylinder and vortex shedding behind the cylinder are investigated. Computed results compare well with experiment data and other numerical results.

关键词： Least-square finite-element method,shallow-water equations Dam-break Vortex shedding

Energy Release Rates for Interface Cracks in Multilayered structures

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Computer Modeling in Engineering & sciences 2019年第8期120卷 261-272页

作者： Changwei Huang Philip A.williams Department of Civil Engineering Chung Yuan Christian UniversityTaoyuan 32023Taiwan simutech solution Corporation 14FNo.90Section 2Nanjing E.Rd.Taipei 10406Taiwan

This paper examines the evolution of the interfacial deflection energy release rates in multilayered structures under four-point *** j-integral and the extended finite element method(XFEM)are adopted to investigate the evolution of the interfacial deflection energy release rates of composite *** results not only verify the accuracy of analytical solutions for the steady-state interfacial deflection energy release rate,but also provide the evolutionary history of the interfacial deflection energy release rate under different crack *** addition,non-dimensional parametric analyses are performed to discuss the effects of normalized ratios of the crack length,the elastic modulus,and the thickness on the interfacial deflection energy release *** results demonstrate that the elastic modulus ratio and thickness ratio have a distinct influence on the interfacial deflection energy release rate for multilayered ***,an unstable interfacial crack tends to occur for elastic multilayer beams with higher elastic modulus on the upper sub-beam under bending *** unstable interfacial fracture shows a decreasing interfacial deflection energy release rate with an increasing interfacial crack length.

关键词： Interfacial deflection energy release rate four-point bending j-integral extended finite element method

Optimization of wear parameters of binary Al-25Zn and Al-3Cu alloys using design of experiments

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International journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1465-1472页

作者： sreejith j s.Ilangovan Department of Mechanical Engineering Amrita School of Engineering

Zinc-aluminum alloys have been used as bearing materials in the past. In recent years, binary Al-Zn alloys and Al-Zn-Cu alloys are being used as an alternative to the Zn-Al alloys for bearing applications. In this study, both binary Al-25 Zn and Al-3 Cu were prepared using stir casting process. Homogenization of the as-cast alloys was performed at 350oC for 8 h and then, the alloys were furnace-cooled to 50oC. The homogenization led to the removal of the dendritic structure of the as-cast alloys. After homogenization, wear parameters optimization was carried out using Taguchi technique. For this purpose, L9 orthogonal array was selected, and the control parameters selected are load, velocity, and sliding distance. The optimum parametric condition was obtained using signal-to-noise(s/N) ratio analysis, and specific wear rate(sWR) is the selected response. The "smaller-the-better" is the goal of the experiment for s/N ratio analysis. After the optimization, confirmation tests were carried out using analysis of variance(ANOVA) from the developed regression equation. Finally, wear mechanism studies were conducted using scanning electron microscopy(sEM) and energy-dispersive X-ray spectroscopy(EDX) images.

关键词： specific wear rate micro-hardness Taguchi technique signal-to-noise ratio analysis of variance aluminum-zinc alloy aluminum-copper alloy

NUMERICAL sIMULATION OF FLOWs FOR sECOND-ORDER VIsCOELAsTIC FLUID COUPLED WITH HEAT TRANsFER BY DIFFERENTIAL QUADRATURE METHOD

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journal of Hydrodynamics 2005年第2期17卷 209-215页

作者： AL-sAIF A.s.j. shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The problem of two-dimensional steady flow of an incompressible second-order viscoelastic fluid coupled with heat transfer between parallel plates was considered. A viscous dissipation function was included in the energy equation. When the elastic property of the fluid is weaker, the zeroth-order and first-order approximate governing equations were obtained by means of the perturbation method. To understand the behavior of flow near the tube wall, the half-domain was divided into two sub-domains, in which one is a thin layer near the wall called the inner domain and the remainder is called the outer domain. The governing equations in the inner domain and in the outer domain were discretized respectively by using the Differential Quadrature Method (DQM). The matching conditions at the interface between the inner and outer domains were presented. An iterative method for solving these discretized equations was given in this paper. The numerical results obtained agree with existing results.

关键词： momentum equations heat equation second-order viscoelastic fluid Differential Quadrature Method (DQM)