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TOWARDS FFT-BASED DIRECT NUMERICAL SIMULATIONS OF TURBULENT FLOWS ON A GPU

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International journal of Modeling, Simulation, and Scientific Computing 2014年第1期5卷 35-47页

作者： catherine RUCkI ABHILASH j.CHANDY Department of Mechanical Engineering The University of Akron AkronOH 44325-3903

The accurate simulation of turbulence and the implementation of corresponding turbulence models are both critical to the understanding of the complex physics behind turbulent flows in a variety of science and engineering *** the tremendous increase in the computing power of central processing units(CPUs),direct numerical simulation of highly turbulent flows is still not feasible due to the need for resolving the smallest length scale,and today’s CPUs cannot keep pace with *** recent development of graphics processing units(GPU)has led to the general improvement in the performance of various *** study investigates the applicability of GPU technology in the context of fast-Fourier transform(FFT)-based pseudo-spectral methods for DNS of turbulent flows for the Taylor–Green vortex *** are implemented on a single GPU and a speedup of unto 31x is obtained in comparison to a single CPU.

关键词： Computational fluid dynamics spectral methods turbulence modeling Taylor-Green vortex GPU programming

The immune modifying effects of amino acids on gut-associated lymphoid tissue

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journal of Animal Science and Biotechnology 2013年第3期4卷 195-204页

作者： Megan R Ruth catherine j Field Department of Agricultural Food and Nutritional Science 4-126A Li Ka Shing Health Research Innovation Centre University of AlbertaEdmonton AB T6G 2E1 Canada

The intestine and the gut-associated lymphoid tissue（GALT） are essential components of whole body immune defense,protecting the body from foreign antigens and pathogens,while allowing tolerance to commensal bacteria and dietary *** requirement for protein to support the immune system is well *** is known regarding the immune modifying properties of individual amino acids,particularly on the *** oral and parenteral feeding studies have established convincing evidence that not only the total protein intake,but the availability of specific dietary amino acids（in particular glutamine,glutamate,and arginine,and perhaps methionine,cysteine and threonine） are essential to optimizing the immune functions of the intestine and the proximal resident immune *** amino acids each have unique properties that include,maintaining the integrity,growth and function of the intestine,as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers,specific T cell functions,and the secretion of IgA by lamina propria *** understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune *** studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states.

关键词： Amino acids Arginine Epithelium Glutamate Glutamine Gut-associated lymphoid tissue Intestine Mucosa

Dryland agriculture and rangeland restoration priorities in Afghanistan

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journal of Arid Land 2015年第3期7卷 391-402页

作者： Michael j jACOBS catherine A SCHLOEDER Philip D TANIMOTO Texas Agri Life Research Department of Ecosystem Science & Management2138TAMUCollege StationTX 77843-2138USA Oikos Services LLCFortineMT 59918USA Conservation Imaging Inc.AuburndaleMassachusetts 02466USA

Afghanistan is threatened by rangeland degradation.A quantitative visual analysis of Google Earth Imagery was used to systematically locate,characterize and quantify the current extent of rangelands in Afghanistan degraded as a consequence of dryland *** data were used in conjunction with dryland agriculture locations to establish a climate envelope comprised by temperature and mean annual precipitation to create a geographical mask known to contain dryland *** this mask we created a grid of 100 km2 cells that we analyzed individually to access dryland agriculture *** limits to sustainable dryland agriculture and areas of high restoration priority were also assessed as was the distribution of rain-fed agriculture with respect to the location of traditional migration routes for extensive livestock *** extents of agriculture in Afghanistan,at both upper and lower elevations,correlated most closely with mean annual temperature（MAT） at the upper elevation limits,and with mean annual precipitation（MAP） at the lower elevation *** total,dryland agriculture comprised 38,980 km2 of former native *** was highest in the northwestern,northern and northeastern provinces of Herat,Badghis,Faryab,jawzjan,Sar-e-Pul,Samangan,Balkh,Baghlan,kunduz,Takhar and Badakhshan,with the highest percentage of conversion occurring in *** MAP value of 〈400 mm is perceived by farmers as the current climatic limit to sustainable dryland agriculture across the northern regions of the *** this MAP value,approximately 27,677 km2 of converted rangeland met the need for restoration *** projections indicate that Afghanistan will become warmer and drier in the coming *** consequence of this trend is that the MAP threshold of 〈400 mm to sustainable dryland agriculture will become obsolete in the coming *** of currently converted rangelands is needed to restore critical grazing area

关键词： degradation climatic trends extensive livestock production dryland agriculture rangeland restoration

Review of post-combustion carbon dioxide capture technologies using activated carbon

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journal of Environmental Sciences 2019年第9期31卷 46-63页

作者： Alivia Mukherjee jude A.Okolie Amira Abdelrasoul catherine Niu Ajay k.Dalai Department of Chemical and Biological Engineering University of Saskatchewan Saskatoon 57 Campus Drive

Carbon dioxide(CO2) is the largest anthropogenic greenhouse gas(GHG) on the planet contributing to the global warming. Currently, there are three capture technologies of trapping CO2 from the flue gas and they are pre-combustion, post-combustion and oxy-fuel combustion. Among these, the post-combustion is widely popular as it can be retrofitted for a short to medium term without encountering any significant technology risks or *** carbon is widely used as a universal separation medium with series of advantages compared to the first generation capture processes based on amine-based scrubbing which are inherently energy intensive. The goal of this review is to elucidate the three CO2 capture technologies with a focus on the use of activated carbon(AC) as an adsorbent for post-combustion anthropogenic CO2 flue gas capture prior to emission to atmosphere. Furthermore, this coherent review summarizes the recent ongoing research on the preparation of activated carbon from various sources to provide a profound understanding on the current progress to highlight the challenges of the CO2 mitigation efforts along with the mathematical modeling of CO2 capture. AC is widely seen as a universal adsorbent due to its unique properties such as high surface area and porous texture. Other applications of AC in the removal of contaminants from flue gas, heavy metal and organic compounds, as a catalyst and catalyst support and in the electronics and electroplating industry are also discussed in this study.

关键词： Post-combustion Greenhouse gas Carbon dioxide capture Activated carbon Adsorption

Implementation of rotational resistance models＇ A critical appraisal

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Particuology 2017年第5期15卷 14-23页

作者： Xin Huang kevin j. Hanley catherine O'Sullivan Chung-Yee kwok a Department of Geotechnical Engineering Tongji University Shanghai 200092 China key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji University Shanghai 200092 China Institute for Infrastructure and Environment School of Engineering The University of Edinburgh Edinburgh EH9 3JL United Kingdom Skempton Building Department of Civil and Environmental Engineering Imperial College London London SW72AZ United Kingdom Haking Wong Building Department of Civil and Environmental Engineering The University ofHong Kong Hong Kong China

Contact models that simulate rotational resistance at particle contacts have been proposed as a means to capture the effect of shape in DEM simulations. This contribution critically explores some key issues related to the implementation of rotational resistance models; these include the need for physically meaningful model parameters, the impact of the model on the overall numerical stability/critical time increment for the DEM model, model validation, and the assessment of model performance relative to real physical materials. The discussion is centred around a rotational resistance model that captures the resistance provided by interlocking asperities on the particle surface. An expression for the maximum permissible integration time step to ensure numerical stability is derived for DEM simulations when rotational resistance is incorporated. Analytical solutions for some single-contact scenarios are derived for model validation. The ability of this type of model to provide additional fundamental insight into granular material behaviour is demonstrated using particle-scale analysis of triaxial compression simulations to examine the roles that contact rollin~ and slidin~ have on the stability of stron：~ force chains.

关键词： Granular mediaParticle shapeDiscrete element methodRollingTwistingRotational resistance

Discrete element modelling of the quasi-static uniaxial compression of individual infant formula agglomerates

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Particuology 2012年第5期10卷 523-531页

作者： kevin j.Hanley catherine O'Sullivan Edmond P.Byrne kevin Cronin Department of Process and Chemical Engineering University College CorkCorkIreland Department of Civil and Environmental Engineering Skempton BuildingImperial College LondonLondon SW7 2AZ United Kingdom

Infant formula is usually produced in an agglomerated powder form. These agglomerates are subjected to many transient forces following their manufacture. These can be difficult to quantify experimentally because of their small magnitudes and short durations, Numerical models have the potential to address this gap in the experimental data. The objective of the research described here was to calibrate a discrete element model for these agglomerates using experimental data obtained for quasi-static loading, and to use this model to study the mechanics of the particle response in detail. The Taguchi method was previously proposed as a viable calibration approach for discrete element models. In this work, the method was assessed for calibration of the model parameters （e.g., bond stiffnesses and strengths） considering three responses： the force at failure, strain at failure and agglomerate stiffness. The Weibull moduli for the simulation results and the experimental data were almost identical following calibration and the 37% characteristic stresses were similar. An analysis of the energy terms in the model provided useful insight into the model response. The bond energy and the normal force exerted on the platens were strongly correlated, and bond breakage events coincided with the highest energy dissipation rates.

关键词： Discrete element modellingUniaxial compressionQuasi-static crushingSimulationGranular materialsTaguchi methods

c-MET immunohistochemical expression in sporadic and inflammatory bowel disease associated lesions

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World journal of Gastroenterology 2022年第13期28卷 1338-1346页

作者： Grant Halliday Ross j Porter catherine j Black Mark j Arends Shahida Din Department of Pathology Western General HospitalNHS LothianScotland EH42XUUnited Kingdom Centre for Inflammation Research Queen’s Medical Research InstituteUniversity of EdinburghEdinburgh EH164TJUnited Kingdom Edinburgh Inflammatory Bowel Disease Unit Western General HospitalNHS LothianEdinburgh EH42XUUnited Kingdom Cancer Research Uk Edinburgh Centre Institute of Cancer&GeneticsWestern General HospitalUniversity of EdinburghEdinburgh EH42XUUnited Kingdom

BACkGROUND Post-colonoscopy colorectal cancer(CRC)rates for patients with inflammatory bowel disease(IBD)are unacceptably *** colonoscopy,an intravenous fluorescent anti-c-MET probe may improve endoscopic detection of ***,c-MET expression in IBD lesions is poorly defined,limiting translational *** To comprehensively define c-MET expression in sporadic and IBD-associated colorectal *** c-MET expression was immunohistochemically assessed in 319 formalin-fixed paraffin-embedded tissue specimens,colonoscopically or surgically retrieved between *** included:30 normal colorectal biopsies,30 hyperplastic polyps(HP),31 sessile serrated lesions(SSL),55 tubular/tubulovillous adenomas with low(TA-LGD,n=32)or high grade dysplasia(TA-HGD,n=23),26 sporadic(s)-CRCs,16 quiescent IBD biopsies,11 active/inflamed IBD biopsies,18 IBDassociated dysplastic lesions(IBD-dys),and 102 *** was scored by two independent observers as:0=absent,1=weak,2=moderate or 3=***-Whitney U and kruskal-Wallis tests were used to assess *** Positive epithelial cytoplasmic and membranous c-MET expression was observed in all tissues,indicating there is ubiquitous expression in the colorectum.c-MET expression was weak in normal colonic epithelium compared with each of the sporadic colonic lesions,including TA-LGD(Pker in quiescent colonic mucosa compared with inflamed colonic mucosa(P<0.001).There was no difference between inflamed colonic mucosa and IBD-dys(P=0.512)or IBD-CRC(P=0.296).However,expression

关键词： Inflammatory bowel diseases Colorectal cancer Surveillance Detection c-MET Immunohistochemistry

Potential of a mixture of eugenol and garlic tincture to improve performance and intestinal health in broilers under necrotic enteritis challenge

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Animal Nutrition 2022年第1期8卷 26-37页

作者： Alip kumar Nishchal k.Sharma Sarbast k.kheravii Chake keerqin catherine Ionescu Alexandra Blanchard Shu-Biao Wu School of Environmental and Rural Science University of New EnglandArmidaleNSW2351Australia ADMi Pancosma SA A-One Business CenterLa piece 3CH-1180RolleSwitzerland

Plant extracts(PE)are gaining increased attention as potential alternatives to in-feed antimicrobials(AM)due to their known antimicrobial *** study was conducted to examine the potential of PE,a microencapsulated product composed of eugenol and garlic tincture as an alternative to AM-agent on performance and intestinal health in broilers under necrotic enteritis(NE)challenge.A total of 960 dayold mixed-sex Cobb 500 chicks were randomly distributed to 48-floor pens with 6 treatments replicated 8 times with 20 birds *** 6 treatments were as follows:UC,unchallenged control;CC,challenged control;PE,challenged group plus PE;AM,challenged group plus AM;FAP,challenged group plus a full dose of AM with PE;HAP,challenged group plus a half dose of AM with PE in starter,grower and finisher *** in the challenged groups were inoculated with Eimeria *** d 9 and Clostridium perfringens on d *** body weight gain(BWG),feed intake(FI),feed conversion ratio(FCR),and livability of birds were compromised,and intestinal lesions and mortality were increased(P<0.05)by NE challenge,illustrating a successful clinical NE *** fed AM had higher BWG and FI,and lower FCR,mortality,and intestinal lesions compared to the CC group(P<0.05).Birds fed PE had improved FCR(P<0.05)and livability(5.8%)in an overall period compared to the CC *** d 16,PE supplementation reduced ileal lesion scores in only male birds(P<0.05).Birds fed PE had decreased Eimeria maxima and Eimeria acervulina oocyst counts in caecal content(P<0.05).Birds fed PE had decreased Eimeria brunetti and total oocyst counts in caecal content,and *** oocyst counts in ileal content in only female birds(P<0.05).On d 35,PE supplementation reduced variation of BW in both male and female birds and increased yellowness(b*value,14.4%)in the *** findings suggest the potential of PE supplementation in diets to improve the performance and intestinal health of birds under clinical NE a

关键词： Plant extract Performance Alternative to antimicrobials Clinical necrotic enteritis Broiler chicken

Emergency department approach to monkeypox

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World journal of Emergency Medicine 2023年第5期14卷 341-348页

作者： catherine V.Levitt Quincy k.Tran Hashem Hraky Maryann Mazer-Amirshahi Ali Pourmand Department of Emergency Medicine George Washington University School of Medicine and Health SciencesWashington DC 20037USA Department of Emergency Medicine University of Maryland School of MedicineBaltimore 21201USA Program in Trauma The R Adams Cowley Shock Trauma CenterUniversity of Maryland School of MedicineBaltimore 21201USA Department of Emergency Medicine MedStar Washington Hospital Center and Georgetown University School of MedicineWashington DC 20037USA

BACkGROUND:Monkeypox(mpox) is a viral infection that is primarily endemic to countries in Africa,but large outbreaks outside of Africa have been historically *** june 2022,mpox began to spread across Europe and North America,causing the World Health Organization(WHO) to declare mpox a public health emergency of international *** article aims to review clinical presentation,diagnosis,and prevention and treatment strategies on mpox,providing the basic knowledge for prevention and control for emergency ***:We conducted a review of the literature using PubMed and SCOPUS databases from their beginnings to the end of july *** inclusion criteria were studies on adult patients focusing on emerging infections that described an approach to a public health emergency of international concern,systematic reviews,clinical guidelines,and retrospective *** that were not published in English were ***:We included 50 studies in this *** initial symptoms of mpox are non-specific:fever,malaise,myalgias,and sore ***,a common presentation of mpox,usually occurs 2–4 weeks after the prodrome,but the presence of lymphadenopathy may distinguish mpox from other infections from the Poxviridae ***-threatening complications such as pneumonia,sepsis,encephalitis,myocarditis,and death can *** are documented co-occurrences of human immunodeficiency virus(HIV) and other sexually transmitted infections that can worsen ***:The initial presentation of mpox is *** preferred treatment included tecovirimat in patients with severe illness or at high risk of developing severe disease and vaccination with two doses of ***,careful history and physical examination can raise the clinicians’ suspicion and point toward a prompt *** are diff erent modalities to prevent and treat mpox infection.

关键词： Monkeypox Emergency medicine Human immunodefi ciency virus Infection