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China Foundry 2023年第2期20卷 148-158页

作者： Osarue Osaruene Edosa francis Kunzi Tekweme Kapil Gupta Department of Mechanical and Industrial Engineering Technology University of JohannesburgJohannesburgRepublic of South Africa Department of Mechanical Engineering College of Engineering and TechnologyWilliam V.S.Tubman UniversityHarperMaryland CountyRepublic of Liberia

Squeeze casting is a well-established and reliable process for fabricating high-integrity metallic alloys,bimetals,and *** quality and high performance of squeeze cast components are dependent on optimum casting *** selection of parameter values may adversely affect the quality of the *** squeeze cast components are generally subjected to secondary processing such as heat treatment,extrusion,and other bulk deformation processes to improve the microstructural features and mechanical *** treatment further refines the grains and reduces porosity,consequently improving tensile strength,and hardness;however,ductility *** paper provides a comprehensive review on studies concerning the influence of processing parameters on porosity,density,percentage elongation,strength,hardness,wear,and fracture of squeeze casting alloys,aiming to provide sufficient information on the squeeze casting process and the effects of processing parameters on product quality.

关键词： composites microstructure optimization porosity solidification squeeze casting

Spatiotemporal variation in the endangered Thymus decussatus in a hyper-arid environment

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Journal of Plant Ecology 2015年第1期8卷 79-90页

作者： Katy Thompson francis Gilbert School of Life Sciences University of NottinghamUniversity ParkNottingham NG72RDUK

Aims Arid environments are resource limited,with scarcity of water the key limiting factor,but hyper-arid environments are rarely *** test for spatial and temporal variation in ecologically important characteristics to deduce plant adaptations to the extreme *** The endangered Sinai Thyme(Thymus decussatus)exists as a set of patches on mountaintops within the St Katherine Protectorate,South Sinai,a hyper-arid environment with rare events of good rains(every 10-15 years).Important Findings From spatial and temporal patterns of plant mortality,size,condition and flowering among 10 patches on the Mt Sinai massif,we deduce that the incidence and amount of flowering responds relatively quickly(1-2 years)to rainfall fluctuations,but plant growth respond only very *** individuals are most at risk of death dur-ing drought,and a high proportion of plants were dead at the end of 8 years of very low or no *** recruitment of seedlings was observed even in years of good *** are expected to become increasingly frequent due to climate change;this may have important consequences for Sinai Thyme and also its associ-ated herbivores,such as the Critically Endangered Sinai Baton Blue(Pseudophilotes sinaicus)whose larval stage feeds exclusively upon the flowers of this plant.

关键词： spatial variation temporal fluctuations resource availability drought Egypt

Structure Identification of Nonlinearly Coupled Complex Networks with Non-Delayed and Delayed Coupling

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Chinese Physics Letters 2010年第3期27卷 68-71页

作者：郭万里 francis Austin 陈士华 School of Mathematics and Statistics Wuhan University Wuhan 430072 Department of Applied Mathematics The Hong Kong Polytechnic University Hong Kong

Topology identification is an important problem for complex networks because much information about networks in practice such as the topological structure is uncertain. We propose an adaptive control method for identifying the topology of general nonlinearly-coupled complex network models that are either non-delayed or delayed coupled. Simulation results are also presented to illustrate the effectiveness of the method.

关键词： Mathematical physics Statistical physics and nonlinear systems

Transcription factor PDX-1 in human colorectal adenocarcinoma:A potential tumor marker?

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World Journal of Gastroenterology 2008年第38期14卷 5823-5826页

作者： Nikiforos Ballian francis Charles Brunicardi the Michael E. DeBakey Department of Surgery Baylor College of Medicine 1709 Dryden Suite 1500 HoustonTX 77030 United States

AIM: To examine the expression of pancreatic duodenal homeobox-1 (PDX-1) transcription factor in human colorectal cancer. METHODS: RT-PCR, Western blotting, and immuno-histochemistry were performed to determine the expression pattern of transcription factor PDX-1 in primary colorectal tumor, hepatic metastasis, and benign colon tissue from a single patient. RESULTS: The highest PDX-1 transcription levels were detected in the metastasis material. Lower levels of PDX-1 were found to be present in the primary tumor, while normal colon tissue failed to express detectable levels of PDX-1. Western blot data revealed a PDX-1 expression pattern identical to that of mRNA expression. Immunohistochemistry confirmed high metastasis PDX-1 expression, lower levels in the primary tumor, and the presence of only traces of PDX-1 in normal colon tissue. CONCLUSION: These data argue for further evaluation of PDX-1 as a biomarker for colorectal cancer.

关键词： Colorectal cancer Pancreatic duodenal homeobox-1 Tumor marker Transcription factor Diagnostics

Endoscopic stenting-Where are we now and where can we go?

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World Journal of Gastroenterology 2008年第24期14卷 3798-3803页

作者： Mark Terence McLoughlin Michael francis Byrne UBC Division of Gastroenterology

Self expanding metal stents (SEMS) play an important role in the management of malignant obstructing lesions in the gastrointestinal tract. Traditionally,they have been used for palliation in malignant gastric outlet and colonic obstruction and esophageal malignancy. The development of the polyflex stent,which is a removable self expanding plastic stent,allows temporary stent insertion for benign esophageal disease and possibly for patients undergoing neoadjuvant chemotherapy prior to esophagectomy. Potential complications of SEMS insertion include perforation,tumour overgrowth or ingrowth,and stent migration. Newer stents are being developed with the aim of increasing technical and clinical success rates,while reducing complication rates. Other areas of development include biodegradable stents for benign disease and radioactive or drug-eluting stents for malignant disease. It is hoped that,in the future,newer stents will improve our management of these diffi cult conditions and,possibly,provide prognostic as well as symptomatic benefi t in the setting of malignant obstruction.

关键词： Endoscopy Stent Palliation Bowel obstruction Malignancy

Status and Trends in Advanced SOI Devices and Materials

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Journal of Semiconductors 2006年第4期27卷 573-582页

作者： Balestra francis Institut de Microélectronique Electromagnétisme et PhotoniqueGrenoble 38016France

A review of recently explored effects in advanced SOI devices and materials is *** effects of key device parameters on the electrical and thermal floating body effects are shown for various device *** advances in the understanding of the sensitivity of electron and hole transport to the tensile or compressive uniaxial and biaxial strains in thin film SOI are *** performance and physical mechanisms are also addressed in multi-gate Si,SiGe and Ge *** hot carrier phenomena are *** effects of gate misalignment or underlap,as well as the use of the back gate for charge storage in double-gate nanodevices and of capacitorless DRAM are also outlined.

关键词： MOSFETs 半导体场效应管疲劳效应灵敏度

Bile acid signaling and biliary functions

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Acta Pharmaceutica Sinica B 2015年第2期5卷 123-128页

作者： Hannah Jones Gianfranco Alpini Heather francis Baylor Scott & White Digestive Disease Research Center Division Research Central Texas Veterans Health Care System Department of Medicine Texas A&M University

This review focuses on various components of bile acid signaling in relation to cholangiocytes. Their roles as targets for potential therapies for cholangiopathies are also explored. While many factors are involved in these complex signaling pathways, this review emphasizes the roles of transmembrane G protein coupled receptor(TGR5), farnesoid X receptor(FXR), ursodeoxycholic acid(UDCA) and the bicarbonate umbrella. Following a general background on cholangiocytes and bile acids,we will expand the review and include sections that are most recently known(within 5–7 years) regarding the field of bile acid signaling and cholangiocyte function. These findings all demonstrate that bile acids influence biliary functions which can, in turn, regulate the cholangiocyte response during pathological events.

关键词： Bile acids Cholangiocytes Receptors Signaling

Selection of optimal land uses for the reclamation of surface mines by using evolutionary algorithms

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International Journal of Mining Science and Technology 2017年第3期27卷 491-498页

作者： Palogos Ioannis Galetakis Michael Roumpos Christos Pavloudakis francis School of Mineral Resources Engineering Technical University of Crete 73100 Chania Greece Public Power Corporation of Greece-Mines Division 104 42 Athens Greece

A methodology for the selection of the optimal land uses of the reclamation of mined areas is proposed. It takes into consideration several multi-nature criteria and constraints, including spatial constrains related to the permissible land uses in certain parts of the mined area. The methodology combines desirability functions and evolution searching algorithms for selection of the optimal reclamation scheme. Its application for the reclamation planning of the Amynteon lignite surface mine in Greece indicated that it handles effectively spatial and non-spatial constraints and incorporates easily the decision-makers preferences regarding the reclamation strategy in the optimization procedure.

关键词： Reclamation Land uses Optimization Evolutionary algorithms Desirability functions

A Grid Middleware for Distributed Java Computing with MPI Binding and Process Migration Supports

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Journal of Computer Science & Technology 2003年第4期18卷 505-514页

作者：陈琳王卓立 francis C.M.Lau Department of Computer Science and Information Systems The University of Hong Kong P.R. China

"Grid" computing has emerged as an important new research field. With years of efforts, grid researchers have successfully developed grid technologies including security solutions,resource management protocols, information query protocols, and data management services. However, as the ultimate goal of grid computing is to design an infrastructure which supports dynamic,cross-organizational resource sharing, there is a need of solutions for efficient and transparent task re-scheduling in the *** this research, a new grid middleware is proposed, called G-JavaMPI. This middleware adds the parallel computing capability of Java to the grid with the support of a Grid-enabled message passing interface (MPI) for inter-process communication between Java processes executed at different grid points. A special feature of the proposed G-JavaMPI is the support of Java process migration with post-migration message redirection. With these supports, it is possible to migrate executing Java process from site to site for continuous computation, if some site is scheduled to be turned down for system reconfiguration. Moreover, the proposed G-JavaMPI middleware is very portable since it requires no modification of underlying OS, Java virtual machine, and MPI package. Preliminary performance tests have been conducted. The proposed mechanisms have shown good migration efficiency in a simulated grid environment.

关键词： grid middleware MPI Java process migration

Influence of lanthanum level and interactions with nitrogen source on early development of Juglans nigra

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Journal of Rare Earths 2009年第2期27卷 270-279页

作者： Nicodemus Michael A Salifu K francis Jacobs Douglass F Department of Forestty and Natural Resources Hardwood Tree Improvement and Regeneration Center Purdue University West Lafayette IN 47907 USA

Rare earth elements have been used for 30 years in Chinese agriculture to improve growth and yield. Numerous scientific studies have shown improvements in physiology, mineral nutrition, and growth, though deleterious effects may also occur. Very few studies have been performed on woody species. We exponentially fertilized one-year old black walnut （Juglans nigra L.） seedlings with 0, 0.1, 1, 10, or 100 mg lanthanum （La） and 800 mg nitrogen （N） as NaNO3, （NH4）2SO4, NH4NO3, or no N. One month following final fertilization, growth, mineral nutrition, photosynthesis, chlorophyll, and nitrate reductase activity were assessed. Plants fertilized with the highest level of La had reduced fine root growth, concentrations of magnesium, calcium, nickel, and phosphorus, photosynthesis levels, and chlorophyll a content. Foliar La concentration showed an interaction effect, with three to four times greater concentration in plants fed at 100 mg La to those given 10 mg La for （NH4）2SO4 and NHaNO3 treatments. The results suggested no beneficial effects of La addition at levels used in this study and interactions between N source and La levels did not have an important impact on the growth, mineral nutrition, or physiology of black walnut seedlings.

关键词： lanthanum nitrate reductase chlorophyll photosynthesis Jugians nigra rare earths