检索结果-南通市图书馆

Designing architected materials for mechanical compression via simulation, deep learning, and experimentation

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2023年第1期9卷 1534-1542页

作者： andrew j.Lew Kai jin Markus j.Buehler Laboratory for Atomistic and Molecular Mechanics(LAMM) Massachusetts Institute of Technology77 Massachusetts Ave.CambridgeMA 02139USA Department of Chemistry Massachusetts Institute of Technology77 Massachusetts Ave.CambridgeMA 02139USA Center for Computational Science and Engineering Schwarzman College of ComputingMassachusetts Institute of Technology77 Massachusetts Ave.CambridgeMA 02139USA

Architected materials can achieve enhanced properties compared to their plain *** architecting serves as a powerful design lever to achieve targeted behavior without changing the base ***,the connection between architected structure and resultant properties remains an open field of great interest to many fields,from aerospace to civil to automotive ***,we focus on properties related to mechanical compression,and design hierarchical honeycomb structures to meet specific values of stiffness and compressive *** do so,we employ a combination of techniques in a singular workflow,starting with molecular dynamics simulation of the forward design problem,augmenting with data-driven artificial intelligence models to address the inverse design problem,and verifying the behavior of de novo structures with experimentation of additively manufactured *** thereby demonstrate an approach for architected design that is generalizable to multiple material properties and agnostic to the identity of the base material.

关键词： thereby additive starting

Zonal jet Creation from Secondary Instability of Drift Waves for Plasma Edge Turbulence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2019年第6期40卷 869-890页

作者： Di QI andrew j.MAjDA Department of Mathematics and Center for Atmosphere and Ocean Science Courant Institute of Mathematical Sciences New York University

A new strategy is presented to explain the creation and persistence of zonal flows widely observed in plasma edge *** core physics in the edge regime of the magnetic-fusion tokamaks can be described qualitatively by the one-state modified Hasegawa-Mima(MHM for short)model,which creates enhanced zonal flows and more physically relevant features in comparison with the familiar Charney-Hasegawa-Mima(CHM for short)model for both plasma and geophysical *** generation mechanism of zonal jets is displayed from the secondary instability analysis via nonlinear interactions with a background base *** exponential growth in the zonal modes is induced due to a non-zonal drift wave base state in the MHM model,while stabilizing damping effect is shown with a zonal flow base *** with the selective decay effect from the dissipation,the secondary instability offers a complete characterization of the convergence process to the purely zonal *** numerical simulations with and without dissipation are carried out to confirm the instability *** shows clearly the emergence of a dominant zonal flow from pure non-zonal drift waves with small perturbation in the initial *** comparison,the CHM model does not create instability in the zonal modes and usually converges to homogeneous turbulence.

关键词： Zonal flow generation Drift wave turbulence Secondary instability Modified Hasegawa-Mima model

Invariant Measures and Asymptotic Gaussian Bounds for Normal Forms of Stochastic Climate Model

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2011年第3期32卷 343-368页

作者： Yuan YUAN andrew j. MAjDA Department of Mathematics Courant Institute New York University 251 Mercer Street New York NY 10012 USA Department of Mathematics and Center for Atmospheric Ocean Sciences Courant Institute New York University 251 Mercer Street New York NY 10012 USA

The systematic development of reduced low-dimensional stochastic climate models from observations or comprehensive high dimensional climate models is an important topic for atmospheric low-frequency variability,climate sensitivity,and improved extended range ***,techniques from applied mathematics have been utilized to systematically derive normal forms for reduced stochastic climate models for low-frequency *** was shown that dyad and multiplicative triad interactions combine with the climatological linear operator interactions to produce a normal form with both strong nonlinear cubic dissipation and Correlated Additive and Multiplicative(CAM) stochastic *** probability distribution functions(PDFs) of low frequency climate variables exhibit small but significant departure from Gaussianity but have asymptotic tails which decay at most like a ***,rigorous upper bounds with Gaussian decay are proved for the invariant measure of general normal form stochastic *** Gaussian lower bounds are also established under suitable hypotheses.

关键词： Reduced stochastic climate model Invariant measure Fokker-Planck equation Comparison principle Global estimates of probability density function

Intensity-specific considerations for exercise for patients with inflammatory bowel disease

在线全文

学校读者我要写书评

暂无评论

Gastroenterology Report 2023年第1期11卷 32-48页

作者： andrew j.Ordille Sangita Phadtare Department of Biomedical Sciences Cooper Medical School of Rowan UniversityCamdenNJUSA

The rising prevalence of inflammatory bowel disease(IBD)necessitates that patients be given increased access to costeffective interventions to manage the *** is a non-pharmacologic intervention that advantageously affects clinical aspects of IBD,including disease activity,immune competency,inflammation,quality of life,fatigue,and psychological *** is well established that exercise performed at low-to-moderate intensity across different modalities manifests many of these diseased-related benefits while also ensuring patient *** less is known about higher-intensity *** aim of this review is to summarize findings on the relationship between strenuous exercise and IBD-related *** healthy adults,prolonged strenuous exercise may unfavorably alter a variety of gastrointestinal(GI)parameters including permeability,blood flow,motility,and neuro-endocrine *** intensity-and gut-specific changes are hypothesized to worsen IBD-related clinical presentations such as diarrhea,GI bleeding,and colonic *** this,there also exists the evidence that higher-intensity exercise may positively influence microbiome as well as alter the inflammatory and immunomodulatory changes seen with *** findings recognize that safety for IBD patients doing prolonged strenuous exercise is no more compromised than those doing lower-intensity *** with prolonged,strenuous exercise may be achieved with adjustments including adequate hydration,nutrition,drug avoidance,and careful attention to patient history and *** work is needed to better understand this intensity-dependent relationship so that guidelines can be created for IBD patients wishing to participate in high-intensity exercise or sport.

关键词： IBD strenuous exercise exercise intensity Crohn’s disease ulcerative colitis

Challenges in studying geographic atrophy(GA) age-related macular degeneration: the potential of a new mouse model with GA-like features

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第5期15卷 863-864页

作者： j. Arjuna Ratnayaka andrew j. Lotery Clinical and Experimental Sciences Faculty of MedicineUniversity of SouthamptonSouthamptonUK Eye Unit University Hospital Southampton NHS Foundation TrustSouthamptonUK

Loss of central vision critical to everyday activities such as reading,face-recognition and driving due to damage in the central retina (the macula) is the leading cause of irreversible blindness amongst adults in the developed *** condition,termed age-related macular degeneration (AMD),is a complex,chronic degenerative disease driven by a combination of genetic and lifestyle risk *** signs of retinal changes in people as young as 30–40 years have been reported,although these individuals appear to be ***,by the age of 65,the disease is present in ~3% of individuals,which increases dramatically to affect 1/3 of individuals by the eighth decade of *** to intermediate AMD is estimated to affect ~150 million individuals globally,with another 10 million individuals suffering from end-stage,sight-threatening *** terminal stages are broadly grouped into dry (geographic atrophy,GA) or wet (choroidal neovascular,CNV) AMD (Sarks et al.,1988;Bird et al.,2014),with similar frequencies reported in *** advances in identifying genetic risk factors,including our discoveries in this field,indicate an initial shared pathology before progressing to aforementioned late-stage ***,GA patients have no effective treatment,which may in part be due to the lack of good in vivo models for GA ***,we summarize our new findings that describe an altogether new mouse model with GA-like features which shows progressive outer retinal pathology (Ibbett et al.,2019) that can be used to gain novel insights into GA and potentially as a tool for drug development.

关键词： macula central vision degenerative disease

Tribological performance of novel nickel-based composite coatings with lubricant particles

在线全文

学校读者我要写书评

暂无评论

Friction 2019年第2期7卷 169-180页

作者： Ignacio TUDELA andrew j.COBLEY Yi ZHANG Daido Metal Co. Ltd.European Technical Centre UKResearch & Development Department Functional Materials Research Centre for Manufacturing and Materials EngineeringFaculty of EngineeringEnvironment and ComputingCoventry University

The present study is focused on the evaluation of the tribological performance of novel Ni/h BN and Ni/WS_2 composite coatings electrodeposited from an additive-free Watts bath with the assistance of ultrasound. Lubricated and non-lubricated scratch tests were performed on both novel composite coatings and on standard Ni deposits used as a benchmark coating to have an initial idea of the effect of the presence of particles within the Ni matrix. Under lubricated conditions, the performance of the Ni/h BN composite coating was very similar to the benchmark Ni coating, whereas the Ni/WS_2 behaved quite differently, as the latter did not only show a lower coefficient of friction, but also prevented the occurrence of stick-slip motion that was clearly observed in the other coatings. Under non-lubricated conditions, whereas the tribological performance of the Ni/hBN composite coating was again very similar to that of the benchmark Ni coating, the Ni/WS_2 composite coatings again showed a remarkable enhancement, as the incorporation of the WS_2 particles into the Ni coating not only resulted in a lower coefficient of friction, but also in the prevention of coating failure.

关键词： nickel tungsten disulphide hexagonal boron nitride composite coatings solid lubricant tribology

Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

在线全文

学校读者我要写书评

暂无评论

journal of Energy Chemistry 2025年第1期100卷 180-191页

作者： Byeongchan Ahn Sua jo jonggeol Na j.jay Liu Young-ju Kim Wangyun Won Department of Chemical and Biological Engineering Korea University Department of Chemical Engineering (Integrated process) Kyung Hee University Department of Chemical Engineering and Materials Science Ewha Womans University Department of Chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOLLAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Carbon capture and utilization

Inhibition of tumor autophagy: a strategy to improve antitumorimmunity?

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2021年第1期6卷 3-4页

作者： andrew jFreeman Emily jLelliott jane Oliaro Cancer Immunology Program Peter MacCallum Cancer CentreMelbourneVIC 3000Australia Sir Peter MacCallum Department of Oncology The University of MelbourneParkvilleVIC 3010Australia Department of Immunology and Pathology Monash UniversityMelbourneVIC 3004Australia

In a study recently published in Nature,Lawson et *** several pathways previously implicated in tumor cell sensitivity to cytotoxic T lymphocytes(CTLs),and identify autophagy as an additional pathway involved in mediating tumor immune evasion.1 Autophagy is a regulated and conserved multistep process that enables cells to degrade and recycle intracellular components and is critical for cellular *** has recently been associated with tumor immune evasion in pancreatic ductal adenocarcinoma,2 whereby this process selectively targeted the degradation of major histocompatibility complex I(MHC-I),limiting recognition,and anti-tumor responses by ***,Lawson et *** an additional role for autophagy in tumor immune evasion,by mediating resistance to cytokine-mediated cell death.

关键词： immunity homeostasis limiting

Assessing the migratory histories, trophic positions, and conditions of lake sturgeon in the St. Croix and Mississippi Rivers using fn ray microchemistry, stable isotopes, and fatty acid profles

在线全文

学校读者我要写书评

暂无评论

Ecological Processes 2021年第1期10卷 1021-1042页

作者： jefrey R.Ziegeweid Michelle R.Bartsch Lynn A.Bartsch Steven j.Zigler Robert j.Kennedy Seth A.love U.S.Geological Survey California Water Science Center6000 J StPlacer HallSacramentoCA 95819USA. U.S.Geological Survey Upper Midwest Water Science Center2280 Woodale DrMounds ViewMN 55112USA. U.S.Geological Survey Upper Midwest Environmental Sciences Center2630 Fanta Reed RoadLa CrosseWI 54603USA. Division of Fisheries Illinois Department of Natural Resources13608 Fox RoadYorkvilleIL 60560USA.

Background:Reproducing populations of invasive carps(Hypophthalmichthys spp.)could alter aquatic food webs and negatively afect native fshes in the Mississippi National River and Recreation Area(MISS)and the *** National Scenic Riverway(SACN).However,proposed invasive carp barriers may also threaten populations of native migratory fshes by preventing movements of fsh between rivers that are necessary for life history *** this study,nonlethal chemical techniques were used to provide baseline data related to the condition,trophic position,and migratory histories of lake sturgeon(Acipenser fulvescens)captured in the Mississippi and *** ***:Fish length and weight measurements and age estimates determined from pectoral fn rays demonstrated that lake sturgeon from the Mississippi River had greater lengths-at-age compared to sturgeon from the *** ***,length–weight relations were similar for sturgeon from the Mississippi and *** *** sturgeon captured from diferent locations had distinguishable fatty acid signatures,and stable isotope analyses demonstrated that lake sturgeon from the Mississippi River generally feed at a higher trophic level than those in the *** ***-to-calcium ratios(Sr:Ca)from fn ray cross sections indicated that sturgeon captured from the Mississippi River had higher Sr:Ca values than sturgeon captured from the *** River,and natal origins and capture locations were not signifcantly diferent among sturgeon captured within individual *** sturgeon were captured in water with a similar Sr:Ca signature as their natal waters,indicating that there is some separation between populations of lake sturgeon in the *** and Mississippi ***,Sr:Ca data indicated substantial variation in movement patterns among individual lake sturgeon,indicating that populations interact through migrations of individual fsh between ***:Study results provide baseline c

关键词： Fin ray microchemistry Stable isotopes Fatty acids Lake sturgeon St.Croix River Mississippi River National park Strontium Calcium