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Communications in Computational Physics 2009年第6期6卷 72-84页

作者： E.Abreu j.douglas F.Furtado F.Pereira Instituto Nacional de Matematica Pura e Aplicada RJ 22460-320Brazil Department of Mathematics Purdue UniversityWest LafayetteIN 47907-1395USA Department of Mathematics University of WyomingLaramieWY 82071-3036USA Department of Mathematics and School of Energy Resources University of WyomingLaramieWY 82071-3036USA

We describe an operator splitting technique based on physics rather than on dimension for the numerical solution of a nonlinear system of partial differential equations which models three-phase flow through heterogeneous porous *** model for three-phase flow considered in this work takes into account capillary forces,general relations for the relative permeability functions and variable porosity and permeability *** our numerical procedure a high resolution,nonoscillatory,second order,conservative central difference scheme is used for the approximation of the nonlinear system of hyperbolic conservation laws modeling the convective transport of the fluid *** scheme is combined with locally conservative mixed finite elements for the numerical solution of the parabolic and elliptic problems associated with the diffusive transport of fluid phases and the pressure-velocity *** numerical procedure has been used to investigate the existence and stability of nonclassical shock waves(called transitional or undercompressive shock waves)in two-dimensional heterogeneous flows,thereby extending previous results for one-dimensional flow *** experiments indicate that the operator splitting technique discussed here leads to computational efficiency and accurate numerical results.

关键词： Operator splitting three-phase flow heterogeneous porous media central differencing schemes mixed finite elements

Potential influence of wildfire in modulating climate-induced forest redistribution in a central Rocky Mountain landscape

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Ecological Processes 2017年第1期6卷 52-68页

作者： john L.Campbell douglas j.Shinneman Department of Forest Ecosystems and Society Oregon State UniversityCorvallisORUSA U.S.Geological Survey Forest and Rangeland Ecosystem Science CenterBoiseIDUSA.

Introduction:Climate change is expected to impose significant tension on the geographic distribution of tree ***,tree species range shifts may be delayed by their long life spans,capacity to withstand long periods of physiological stress,and dispersal *** could theoretically break this biological inertia by killing forest canopies and facilitating species redistribution under changing *** investigated the capacity of wildfire to modulate climate-induced tree redistribution across a montane landscape in the central Rocky Mountains under three climate scenarios(contemporary and two warmer future climates)and three wildfire scenarios(representing historical,suppressed,and future fire regimes).Methods:Distributions of four common tree species were projected over 90 years by pairing a climate niche model with a forest landscape simulation model that simulates species dispersal,establishment,and mortality under alternative disturbance regimes and climate ***:Three species(douglas-fir,lodgepole pine,subalpine fir)declined in abundance over time,due to climate-driven contraction in area suitable for establishment,while one species(ponderosa pine)was unable to exploit climate-driven expansion of area suitable for *** fire frequency accelerated declines in area occupied by douglas-fir,lodgepole pine,and subalpine fir,and it maintained local abundance but not range expansion of ponderosa ***:Wildfire may play a larger role in eliminating these conifer species along trailing edges of their distributions than facilitating establishment along leading edges,in part due to dispersal limitations and interspecific competition,and future populations may increasingly depend on persistence in locations unfavorable for their establishment.

关键词： Forest disturbance Wildfire Climate change Central Rocky Mountains Climate niche Species migration Species distribution

Parallel boron nitride nanoribbons and etch tracks formed through catalytic etching

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Nano Research 2018年第9期11卷 4874-4882页

作者： Armin Ansary Mohsen Nasseri Mathias j. Boland douglas R. Strachan Department of Physics &Astronomy University of Kentucky Lexington KY40506 USA

One-dimensional （1D） catalytic etching was investigated in few-layer hexagonal boron nitride （hBN） films. Etching of hBN was shown to share a number of similarities with that of graphitic films. As in graphitic films, etch tracks in hBN commenced at film edges and occurred predominantly along certain crystal directions of its lattice, though it was shown that the tracks were generally narrower than those of few-layer graphene under similar processing conditions. It was also shown that catalytic hydrogenation can occur completely through a few-layer hBN film, demonstrating that this process can be used in the formation of isolated low-dimensional nanoscale structures from other layered 2D materials beyond graphene. This ability for thin hBN films to be etched completely through allowed for a crystalline substrate to guide the etching process, which was demonstrated with the successful etch track formation of few-layer hBN on single-crystalline sapphire substrates. The substrate-guided etching resulted in parallel few-layer hBN nanoribbons having an average width of 32 nm and spacing of 13 nm.

关键词： hexagonal(hBN) one-dimensional catalytic etching hydrogenation etch tracks nanoribbons

Gastroenterologist perceptions of faecal microbiota transplantation

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World journal of Gastroenterology 2015年第38期21卷 10907-10914页

作者： Sudarshan Paramsothy Alissa j Walsh Thomas Borody douglas Samuel johan van den Bogaerde Rupert WL Leong Susan Connor Watson Ng Hazel M mitchell Nadeem O Kaakoush Michael A Kamm Gastroenterology and Hepatology Department St Vincent’s Hospital Centre for Digestive Diseases Gastroenterology and Hepatology Department Bankstown-Lidcombe Hospital Gastroenterology and Hepatology Department Nambour General Hospital Gastroenterology and Hepatology Department Liverpool Hospital University of New South Wales School of Biotechnology and Biomolecular Sciences Departments of Gastroenterology and Medicine St Vincent's Hospital and University of Melbourne

AIM: To explore gastroenterologist perceptions towards and experience with faecal microbiota transplantation(FMT).METHODS: A questionnaire survey consisting of 17 questions was created to assess gastroenterologists' attitude towards and experience with FMT. This was anonymously distributed in hard copy format amongst attendees at gastroenterology meetings in Australia between October 2013 and April 2014. Basic descriptive statistical analyses were ***: Fifty-two clinicians participated. Twenty one percent had previously referred patients for FMT,8% more than once. Ninety percent would refer patients with Clostridium difficile infection(CDI) for FMT if easily available,37% for ulcerative colitis,13% for Crohn's disease and 6% for irritable bowel syndrome. Six percent would not refer any indication,including recurrent CDI. Eighty-six percent would enroll patients in FMT clinical trials. Thirty-seven percent considered the optimal mode of FMT administration transcolonoscopic,17% nasoduodenal,13% enema and 8% oral capsule. The greatest concerns regarding FMT were: 42% lack of evidence,12% infection risk,10% non infectious adverse effects/lack of safety data,10% aesthetic,10% lack of efficacy,4% disease exacerbation,and 2% inappropriate use; 6% had no concerns. Seventy seven percent believed there is a lack of accessibility while 52% had an interest in learning how to provide FMT. Only 6% offered FMT at their ***: Despite general enthusiasm,most gastroenterologists have limited experience with,or access to,FMT. The greatest concerns were lack of supportive evidence and safety issues. However a significant proportion would refer indications other than CDI for FMT despite insufficient evidence. These data provide guidance on where education and training are required.

关键词： Perceptions Gastroenterologist Clostridium diffici

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美国普利策奖金内幕

Slab and Level 2 Automation Design Guidelines for Optimum Metallurgy and Productivity for Plate and Steckel Mills

1993年

作者：（美）贝茨（Bates j.douglas）贾宗谊译

书名原文:The Pulitzer prize:the inside story of America's most Prestigious award:普利策,美国报业大王,“普利策奖金”是1917年开始颁发的美国新闻奖。本书介绍了普利策传奇般的一生和设立普利策奖金的前后经过、评选方法、组织... 详细信息

ISBN: (数字)7501118582

ISBN: (纸本)7501118582

书名原文:The Pulitzer prize:the inside story of America's most Prestigious award:普利策,美国报业大王,“普利策奖金”是1917年开始颁发的美国新闻奖。本书介绍了普利策传奇般的一生和设立普利策奖金的前后经过、评选方法、组织机构、颁奖情况等。

关键词：普利策学科:传记新闻事业史地点:美国年代:现代

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journal of Iron and Steel Research International 2011年第S1期18卷 550-556页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA 98684 USA

Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the *** is especially true in developing countries such as China,India and *** of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate ***,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product *** mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you *** this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or *** less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing *** is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical *** critical nature of this selection will be dependent on the final plate thickness and overall mechanical property *** mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling *** mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during *** ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manual

关键词： slab dimensions optimization grain size rolling schedule automation Level 2

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Metallurgical Optimization of Microalloyed Steels for Oil and Gas Transmission Pipelines

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journal of Iron and Steel Research International 2011年第S1期18卷 669-674页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA98684 USA

The production of microalloyed steels for oil and gas transmission pipelines has increased significantly over the past *** more and more countries developing their own capabilities to produce pipeline steels to support their own internal pipeline infrastructure development,there has been an increase of steel producers working to develop their own capabilities to produce microalloyed steels for this ***,to achieve the desired mechanical property attributes for transmission pipeline applications utilizing a cost effective approach requires metallurgical optimization of the microalloyed *** achieve metallurgical optimization a basic understanding is required in the design of a cost effective alloy and then the proper processing of that alloy design to achieve the optimum microstructure/mechanical *** this sense,many producers in the world,especially those who have only recently,in the past 10 years,developed their capability to produce microalloyed transmission pipeline steels still do not achieve metallurgical optimization of their alloy and *** results in yield losses due to failures,inefficient processing causing productivity losses and additional expensive additions of alloys to compensate for failures and process *** the supplier of plate/coil has the largest percentage effect on the final cost of the pipe,the steel producer must understand proper alloy,microstructure,and process design to produce a uniform and stable plate/coil to be used in pipe *** means that strength,toughness and microstructure must be uniform down the length,across the width and through the cross *** optimization is achieved when this uniformity is achieved with a cost effective *** to that,non-uniformity results in pipe forming,welding,expansion,mechanical property and production issues resulting in downgraded pipe and cost overruns in *** paper will describe targets for p

关键词： microalloy niobium pipeline solubility grain size rolling schedule

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弱非线性橢圓型差分方程的交替方向迭代法

计算机研究与发展 1963年第2期 34-38页

作者： j.douglas 鮑信烱金旦华

1.引言.椭圆型微分方程的有限差分数值解法,导至求解线性或非线性高阶代数方程组的问题。最简单的这种问题是矩形域的Di-richlet问题: {（△+△）w=f,（x,y）=（i△x,j△y）∈R,w=g,（x,y）∈R,（1.1）其中△是关于x的二阶中心差商。如... 详细信息

1.引言.椭圆型微分方程的有限差分数值解法,导至求解线性或非线性高阶代数方程组的问题。最简单的这种问题是矩形域的Di-richlet问题: {（△+△）w=f,（x,y）=（i△x,j△y）∈R,w=g,（x,y）∈R,（1.1）其中△是关于x的二阶中心差商。如果在R中,

关键词：交替方向迭代法差分方程逐次超松弛法

Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

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Bone Research 2015年第1期3卷 40-45页

作者： douglas j DiGirolamo Vandana Singhal Xiaoli Chang Se-jin Lee Emily L Germain-Lee Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Bone & Osteogenesis Imperfecta Department Kennedy Krieger Institute Department of Molecular Biology and Genetics Johns Hopkins University School of Medicine Department of Pediatrics Johns Hopkins University School of Medicine

Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.

关键词： bone Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

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