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SPH Particle Collisions for the Reduction of Particle Clustering, Interface Stabilisation and Wall Modelling

Journal of Applied Mathematics and Physics 2018年第9期6卷 1860-1882页

作者： Arno kruisbrink stan korzilius Frazer Pearce Hervé Morvan Gas Turbine and Transmission Research Centre University of Nottingham Nottingham UK Centre for Analysis Scientific Computing and Applications Eindhoven University of Technology Eindhoven The Netherlands

The pair-wise forces in the SPH momentum equation guarantee the conservation of momentum, but they cannot prevent particle clustering and wall penetration. Particle clustering may occur for several reasons. A fundamental issue is the tensile instability, which is caused by negative numerical pressures. Clustering may also occur due to certain properties of the kernel gradient. Discontinuities in the pressure and its gradient, due to surface tension and gravity, may cause particle instabilities near the interface between two fluids. Wall penetration is also a form of particle clustering. In this paper the particle collision concept is introduced to suppress particle clustering. Here, the use of kinematic conditions (motion) rather than dynamic conditions (forces) is explored. These kinematic conditions are obtained from kinetic collision theory. Conservation of momentum is maintained, and under elastic conditions conservation of energy as well. The particle collision model only becomes active when needed. It may be seen as a particle shifting method, in the sense that the velocities are changed, and as a consequence of that the particle positions change. It is demonstrated in several case studies that the particle collision model allows for realistic (low) viscosities. It was also found to stabilise the interface between two fluids up to high, realistic density ratios (1000:1) in typical liquid-gas applications. As such it can be used as a multi-fluid model. The concept allows for real wave speed ratios (and far beyond), which, as well as real viscosities, are essential in the modelling of heat transfer applications. The collisions with walls allow for no-slip conditions at real viscosities while wall penetration is suppressed. In summary, the particle collision model makes SPH more robust for engineering.

关键词： SPH Particle Clustering Multiphase Flow Interface Stabilisation Wall Modelling

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Effect of vascular endothelial growth factor （VEGF） on superoxide anion and endothelial function in streptozotocin （STZ）-induced diabetic rats

Effect of vascular endothelial growth factor （VEGF） on sup...

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第十五届国际药理学大会

作者： Bardal stan McNeill J Robert Department of Pharmacology University of Saskatchewan Department of Pharmacology University of Saskatchewan

＜正＞ The aim of this study was to determine if the ability of VEGF to preserve vasodilatory responses to acetylcholine （Ach） in the STZ-induced diabetic rats was related to superoxide anion generation. After induction of diabetes,changes in arterial pressure （BP） and superior mesenteric arterial （SMA） flow to i.v. infusions of Ach （0.1 - 12.5mg/kg） were recorded in anesthetized rats treated with VEGF or iVEGF. In other rats,superoxide anion generation and endothelial nitric oxide synthase （ eNOS） expression were determined in isolated aorta. The changes in BP and SMA conductance （SMAC） to Ach were attenuated in iVEGF treated STZ rats but not in non-diabetic SD rats. VEGF prevented the decrease in Ach-evoked responses observed in iVEGF treated STZ rats,and it prevented the dramatic increases in superoxide generation in these rats. Paradoxically. eNOS expression was enhanced in STZ rats and VEGF prevented these changes,findings that may be related to the " coupled/uncoupled "state of the enzyme. The results suggest that the preservation of Ach evoked responses by VEGF may be related to normalizing the oxidative stress environment of diabetic state.

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硫代硫酸银和氨基乙氧乙烯甘氨酸对延长矮牵牛花期的效应

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江苏农业科学 1994年第3期22卷 55-56页

作者：徐明全 stan Jk 江苏省农科院园艺所

硫代硫酸银和氨基乙氧乙烯甘氨酸对延长矮牵牛花期的效应徐明全ＳｔａｎｌｅｙＪ．Ｋａｙｓ（江苏省农科院园艺所南京２１００１４）（ＤｅｐａｒｔｍｅｎｔｏｆＨｏｒｔｉｃｕｌｔｕｒｅＵｎｉｖｅｒｓｉｔｙｏｆＧｅｏｒｇｉａ）矮牵... 详细信息

硫代硫酸银和氨基乙氧乙烯甘氨酸对延长矮牵牛花期的效应徐明全ＳｔａｎｌｅｙＪ．Ｋａｙｓ（江苏省农科院园艺所南京２１００１４）（ＤｅｐａｒｔｍｅｎｔｏｆＨｏｒｔｉｃｕｌｔｕｒｅＵｎｉｖｅｒｓｉｔｙｏｆＧｅｏｒｇｉａ）矮牵牛是一种广泛用于盆栽和花坛的花卉，...

关键词：牵牛花硫代硫酸银 AVG 花期

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New solutions for combatting implant bacterial infection based on silver nano-dispersed and gallium incorporated phosphate bioactive glass sputtered films:A preliminary study

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Bioactive Materials 2022年第2期7卷 325-340页

作者： B.W.Stuart G.E.stan A.C.Popa M.J.Carrington I.Zgura M.Necsulescu D.M.Grant m.grantadvanced materials research group faculty of engineeringuniversity of nottinghamnottinghamng72rduk national institute of materials physics magurelero077125romania army centre for medical research bucharestro010195romania

Ag/Ga were incorporated into resorbable orthopaedic phosphate bioactive glasses(PBG,containing P,Ca,Mg,Na,and Fe)thin films to demonstrate their potential to limit growth of Staphylococcus aureus and Escherichia coli in post-operative prosthetic *** target consecutive co-sputtering was uniquely employed to produce a 46 nm Ag:PBG composite observed by high resolution TEM to consist of uniformly dispersed~5 nm metallic Ag nano-particles in a glass ***^(3+)was integrated into a phosphate glass preform target which was magnetron sputtered to film thicknesses of~400 or 1400 *** coatings exhibited high surface energy of 75.4-77.3 mN/m,attributed to the presence of hydrolytic P-O-P structural surface *** profiles obtained in deionized water,nutrient broth and cell culture medium showed varying ion release profiles,whereby Ga release was measured in 1400 nm coating by ICP-MS to be~6,27,and 4 ppm respectively,fully dissolving by 24 *** of Ag nanoparticles was only observed in nutrient broth(~9 ppm by 24 h).Quantification of colony forming units after 24 h showed encouraging antibacterial efficacy towards both ***(4-log reduction for Ag:PBG and 6-log reduction for Ga-PBG≈1400 nm)and ***(5-log reduction for all physical vapour deposited layers)*** Hs27 fibroblast and mesenchymal stem cell line in vitro tests indicated good cytocompatibility for all sputtered layers,with a marginal cell proliferation inertia in the case of the Ag:PBG composite thin *** study therefore highlights the(i)significant manufacturing development via the controlled inclusion of metallic nanoparticles into a PBG glass matrix by dual consecutive target co-sputtering and(ii)potential of PBG resorbable thin-film structures to incorporate and release cytocompatible/antibacterial *** architectures showed prospective bio-functional performance for a future generation of endo-osseous implant-type coatings.

关键词： Phosphate bioactive glass Silver Gallium Antibacterial Implant coating Magnetron sputtering

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Logical Function Decomposition Method for Synthesis of Digital Logical System Implemented with Programmable Logic Devices (PLD)

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Circuits and Systems 2013年第7期4卷 472-477页

作者： Mihai Grigore Timis Alexandru Valachi Alexandru Barleanu Andrei stan Automatic Control and Computer Engineering Faculty Technical University Gh.Asachi Iasi Romania

The paper consists in the use of some logical functions decomposition algorithms with application in the implementation of classical circuits like SSI, MSI and PLD. The decomposition methods use the Boolean matrix calculation. It is calculated the implementation costs emphasizing the most economical solutions. One important aspect of serial decomposition is the task of selecting “best candidate” variables for the G function. Decomposition is essentially a process of substituting two or more input variables with a lesser number of new variables. This substitutes results in the reduction of the number of rows in the truth table. Hence, we look for variables which are most likely to reduce the number of rows in the truth table as a result of decomposition. Let us consider an input variable purposely avoiding all inter-relationships among the input variables. The only available parameter to evaluate its activity is the number of “l”s or “O”s that it has in the truth table. If the variable has only “1” s or “0” s, it is the “best candidate” for decomposition, as it is practically redundant.

关键词： Combinational Circuits Static Hazard Logic Design Boolean Functions Logical Decompositions

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Two Analytical Methods for Detection and Elimination of the Static Hazard in Combinational Logic Circuits

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Circuits and Systems 2013年第7期4卷 466-471页

作者： Mihai Grigore Timis Alexandru Valachi Alexandru Barleanu Andrei stan Automatic Control and Computer Engineering Faculty Technical University Gh.Asachi Iasi Romania

In this paper, the authors continue the researches described in [1], that consists in a comparative study of two methods to eliminate the static hazard from logical functions, by using the form of Product of Sums (POS), static hazard “0”. In the first method, it used the consensus theorem to determine the cover term that is equal with the product of the two residual implicants, and in the second method it resolved a Boolean equation system. The authors observed that in the second method the digital hazard can be earlier detected. If the Boolean equation system is incompatible (doesn’t have solutions), the considered logical function doesn’t have the static 1 hazard regarding the coupled variable. Using the logical computations, this method permits to determine the needed transitions to eliminate the digital hazard.

关键词： Combinational Circuits Static Hazard Logic Design Boolean Functions

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Comparison of Five Expression Vectors for the Ha Gene in Constructing a DNA Vaccine for H6N2 Influenza Virus in Chickens

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Advances in Microbiology 2016年第4期6卷 310-319页

作者： Songhua Shan Trevor Ellis John Edwards stan Fenwick Ian Robertson School of Veterinary and Life Sciences Murdoch University Perth Australia

A number of eukaryotic expression vectors have been developed for use as DNA vaccines. They showed varying abilities to initiate immune responses;however, there is little data to indicate which of these vectors will be the most useful and practical for DNA vaccines in different species. This report examines the use of five expression vectors with different promoters and kozak sequence to express the same hemagglutinin (HA) protein of an H6N2 avian influenza virus for DNA vaccination in chickens. Although intramuscular vaccination with seven DNA constructs elicited no or limited measurable H6 HA antibody responses in Hy-Line chickens, variable reduction in virus shedding for either oropharyngeal or cloacal swabs post-virus challenge were observed. This indicated that all DNA constructs generated some levels of protective immunity against homologous virus challenge. Interestingly, lower dose (50 or 100 μg) of plasmid DNAs consistently induced better immune response than higher dose (300 or 500 μg). In the transfection experiments there appeared to be a hierarchy in the in vitro expression efficiency in the order of pCAG-optiHAk/ pCAG-HAk > pCI-HAk > VR-HA > pCI-HA > pCI-neo-HA > pVAX-HA. Since the level of in vitro expression correlates with the level of immune response in vivo, in vitro expression levels of the DNA constructs can be used as an indicator for pre-selection of plasmid vaccines prior to in vivo assessment. Moreover, our results suggested that the kozak sequence could be used as an effective tool for DNA vaccine design.

关键词： DNA Vaccine Multiple Expressing Vectors H6N2 Avian Influenza a Virus Chickens

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The influence of metabolic imbalances and oxidative stress on the outcome of critically ill polytrauma patients: a review

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Burns & Trauma 2017年第1期5卷 17-23页

作者： Alexandru Florin Rogobete Dorel Sandesc Marius Papurica Emil Robert Stoicescu Sonia Elena Popovici Lavinia Melania Bratu Corina Vernic Adriana Mariana Sas Adrian Tudor stan Ovidiu Horea Bedreag Faculty of Medicine Victor Babes University of Medicine and PharmacyStr.Eftimie Murgu Nr.2Timisoara300041TimisRomania Clinic of Anaesthesia and Intensive Care Emergency County Hospital“PiusBrinzeu”Bd.Liviu Rebreanu Nr.156Timisoara300736TimisRomania

The critically ill polytrauma patient presents with a series of associated pathophysiologies secondary to the traumatic injuries. The most important include systemic inflammatory response syndrome (SIRS), sepsis, oxidative stress (OS), metabolic disorders, and finally multiple organ dysfunction syndrome (MODS) and death. The poor outcome of these patients is related to the association of the aforementioned pathologies. The nutrition of the critically ill polytrauma patient is a distinct challenge because of the rapid changes in terms of energetic needs associated with hypermetabolism, sepsis, SIRS, and OS. Moreover, it has been proven that inadequate nutrition can prolong the time spent on a mechanical ventilator and the length of stay in an intensive care unit (ICU). A series of mathematical equations can predict the energy expenditure (EE), but they have disadvantages, such as the fact that they cannot predict the EE accurately in the case of patients with hypermetabolism. Indirect calorimetry (IC) is another method used for evaluating and monitoring the energy status of critically ill patients. In this update paper, we present a series of pathophysiological aspects associated with the metabolic disaster affecting the critically ill polytrauma patient. Furthermore, we present different non-invasive monitoring methods that could help the intensive care physician in the adequate management of this type of patient.

关键词： Critically ill Energy expenditure Indirect calorimetry Metabolic disaster Oxidative stress Overfeeding Underfeeding Polytrauma

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Population Characteristics of Ozark Bass (<i>Ambloplites constellatus</i>) in the Upper White River Basin of Northern Arkansas

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Natural Resources 2019年第5期10卷 121-138页

作者： Ashley Rodman kristofor R. Brye Daniel Magoulick stan Todd Buffalo National River National Park Service Harrison AR USA Department of Crop Soil and Environmental Sciences University of Arkansas Fayetteville USA U.S. Geological Survey Arkansas Cooperative Fish and Wildlife Research Unit Department of Biological Sciences University of Arkansas Fayetteville USA Arkansas Game and Fish Commission Little Rock AR USA

Ozark Bass (Ambloplites constellatus) is an understudied, endemic fish species in the Upper White River Basin of northern Arkansas. This study was part of an effort by fisheries managers to gather baseline data about the Ozark Bass to aid in understanding population dynamics and contribute to the limited data available for use in determining the efficacy of harvest regulations. Select population characteristics of Ozark Bass in two northern Arkansas streams were determined, population characteristics of Ozark Bass were compared to Shadow Bass (Ambloplites ariommus) and Rock Bass (Ambloplites rupestris) data collected from previous studies in southern Missouri, and relative condition, length-at-age, and annual survival of Ozark Bass were compared between sample streams. Sampling occurred in Crooked Creek and the Buffalo River during summer 2013 via boat electroshocking. Length and weight data were recorded for all Ozark Bass collected, and fish ages were determined through selective otolith retrieval and age-length keys. Ozark Bass in Crooked Creek had greater relative condition than Ozark Bass in Buffalo River (P P > 0.05) between sexes for fish collected from only the Buffalo River. Ozark Bass mean annual survival was similar between Crooked Creek (55% ± 5% as 95% confidence interval (CI)) and the Buffalo River (50% ± 7% CI) for fish age 2 to 9. Calculated Ozark Bass lengths-at-age for fish from both streams were comparable to the Von Bertalanffy growth estimates, except the Buffalo River age 7 category where there was only one observation. The relationship between Ozark Bass age and length differed between sampled streams, and variability in growth rates and length-at-age were observed among Ambloplites species. Results of this study contribute to the understanding of the population dynamics of the Ozark Bass that will lead to improved fisheries management.

关键词： Endemic Fish Measurements Fishing Regulations Ozarks

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The Global Boundary Stratotype Section and Point （GSSP） for the base of the Hirnantian Stage （the uppermost of the Ordovician System）

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Episodes 2006年第3期29卷 183-196页

作者： Xu Chen Jiayu Rong Junxuan Fan Renbin Zhan Charles E. Mitchell David A. T. Harper Michael J. Melchin Ping＇an Peng stan C. Finney Xiaofeng Wang State key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 39 East Beijing Road Nanjing 210008 China Department of Geology the State University of New York at Buffalo NY 14260-3050 USA. Geological Museum University of Copenhagen Фster Voldgade 5-7 DK-1350 Copenhagen Denmark Department of Earth Sciences St. Francis Xavier University Antigonish N.S. B2G 2W5 Canada State key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Department of Geological Sciences California State University at Long Beach Long Beach CA 90840 USA. Yichang Institute of Geology and Mineral Resources 21 Gangyao Road Yichang 443003 China.

The Global boundary Stratotype Section and Point （GSSP） for the base of the Hirnantian Stage （the uppermost of the Ordovician System） is defined at a point 0.39m below the base of the kuanyinchiao Bed in the Wangjiawan North section. The section is located near Wangjiawan village, 42 km north of Yichang city （western Hubei, China）, at 30° 58′56″N and 111° 25′10″E. The GSSP level coincides with the first appearance of the graptolite species Normalograptus extraordinarius （Sobolevskaya）. Secondary markers include the onset of a positive carbon-isotope excursion, and a slightly earlier first appearance of Normalograptus ojsuensis （ koren and Mikhailova ）. The Wangjiawan North section possesses continuity of sedimentation and biozonation with completeness of exposures, abundant and well-preserved graptolites and shelly fossils, i. e. the Hirnantia- Dalmanitina shelly fauna which is a key element for recognition of the Hirnantian Stage. The Wangjiawan North, South and Riverside sections possess favorable facies and widespread correlation potential, are free from structure complication, metamorphism and other alteration, and have good accessibility. The Riverside section in particular possesses amenability to isotopic age determination. The beginning of the Hirnantian was followed by a global episode of a major extinction event, which happened in the Diceratograptus mirus Subzone. The proposal was voted by the International Subcommission on Ordovician Stratigraphy in October, 2004, approved by the International Commission on Stratigraphy in February, 2006, and ratified by the International Union of Geological Sciences in May, 2006.

关键词：全球界线层型剖面和节点奥陶纪 GSSP 地层学

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