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MORpHOLOGY OF AMORpHOUS SILICA DURING ALUMINUM REACTIVE pENETRATION

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 944-948页

作者： Zhou, Z. Gan, Q.S. Ding, p.D. Chongqing Univ Chongqing China

The reduction of volume of silica glass during aluminum reactive penetration was observed experimentally. The liquid aluminum infiltrates easily into the cavities while the released silicon is solved in the liquid aluminum, and Al/Al2O3 composites could be obtained. The experimental results show that Al/Al2O3 composites can be transformed into Al2O3 grains by oxygen in the cavities of Al/Al2O3 composites during the longer penetration treatment. The formation of alumina is a sintering process, in which liquid aluminum, particulate alumina and oxygen play an important role. The transformtion process has shown that there is a relationship of σAl2O3-Al2O3 2O3-Al, where σAl2O3-Al2O3 is the grain boundary energy of alumina, and σAl2O3-Al is the interface energy between aluminum and alumina. The formation temperature by aluminum reactive penetration is much lower than that by sintering.

关键词： Alumina Aluminum Metallic matrix composites Morphology Silica

A review of concurrent infections of malaria and dengue in Asia

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Asian pacific Journal of Tropical Biomedicine 2016年第7期6卷 633-638页

作者： Aruchana A/p Selvaretnam priyadarshi Soumyaranjan Sahu Madhusmita Sahu Stephen Ambu Division of Biomedical Sciences and Biotechnology School of Health SciencesInternational Medical University Division of pathology School of MedicineInternational Medical University Centre for public Health Informatics Asian Institute of Public Health

Concurrent infections of malaria and dengue are when both of these mosquito-borne diseases occur simultaneously in an individual. In this review, reported cases with these co-infections in Asia are discussed. The focus is on the overlapping clinical presentations and the difficulties encountered in differential diagnosis. Also, cases reported in some special conditions, viz., pregnancy, foetal infections, and co-infections with one or more other infectious agents are highlighted. Due to similar clinical presentations of malaria and dengue, these co-infections may give rise to an incorrect diagnosis. Moreover, the treatment regimens for these co-infections are not the same as those for ***, a delay in implementing the appropriate treatment regimen for these concurrent infections due to poor diagnosis can be fatal. The present review is intended to increase awareness about the clinical significance and the importance of these co-infections among clinicians, public health workers and health authorities in the Asian region. Though malaria-dengue concurrent infections are seldom reported from the Asian region, it is probably increasing particularly in the countries known to be endemic for both of the above diseases. A compulsory reporting of the incidences of malaria-dengue concurrent infections is recommended.

关键词： Concurrent infection Co-infection Malaria Dengue Asia

Agent-Based Simulation for Interconnection-Scale Renewable Integration and Demand Response Studies

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Engineering 2015年第4期1卷 422-435页

作者： David p.Chassin Sahand Behboodi Curran Crawford Ned Djilali Department of Mechanical Engineering University of Victoria Institute for Integrated Energy Systems University of Victoria pacific Northwest National Laboratory Department of Mechanical Engineering University of Victoria Victoria BC V8W 2Y2 Canada Renewable Energy Research Group King Abdulaziz University

This paper collects and synthesizes the technical requirements, implementation, and validation methods for quasi-steady agent-based simulations of interconnectionscale models with particular attention to the integration of renewable generation and controllable loads. Approaches for modeling aggregated controllable loads are presented and placed in the same control and economic modeling framework as generation resources for interconnection planning studies. Model performance is examined with system parameters that are typical for an interconnection approximately the size of the Western Electricity Coordinating Council(WECC) and a control area about 1/100 the size of the system. These results are used to demonstrate and validate the methods presented.

关键词： interconnection studies demand response load control renewable integration agent-based simulation electricity markets

INFLUENCE OF GEOMETRIC pARAMETERS ON CENTRIFUGAL FAN pERFORMANCE AND ITS SIGNIFICANCE IN AUTOMOTIVE AppLICATIONS

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International Journal of Modeling, Simulation, and Scientific Computing 2012年第3期3卷 18-35页

作者： O.p.SINGH T.SREENIVASULU M.KANNAN TVS Motor Company Hosur 635109 TamilnaduIndia

In this paper,the effect of geometrical parameters of centrifugal fan on performance has been presented with a system ***,the operators or the design engineers focus on the immediate requirements of the engine/equipment and they neglect the broader question of how the fan parameters are affecting the *** instance,change in fan angles will change the performance e.g.,airflow rates and ***,it also affects the contaminants build-up on the *** angle with higher angle of attack will promote contaminants build-up on blade surfaces,which in turn causes performance degradation and unstable *** system approach in fan parameter selection will result in a more reliable *** of other fan parameters is also *** present an experimental setup and validated computational fluid dynamic(CFD)*** power consumption is determined experimentally and compared with the CFD *** parametric simulations were carried out to investigate the effect on fan *** of system resistance,inlet and outlet angle,blade thickness,and no-uniform spaced blades has been described with discussions on industrial relevance.A fan with higher flow rates is desirable to reduce engine temperatures and enhance the ***,higher flow rates result in more fan power consumption at a given fan *** test results suggest that a fan with higher power coefficient does not affect the vehicle’s mileage *** paper will help design engineers in making informed decision about the interaction between the fans and system,and its effect during the operation.

关键词： Centrifugal fan industrial significance fan performance vehicle mileage CFD

Cardiac remodeling as a consequence of atrial fibrillation： An anatomical study of perfusion-fixed human heart specimens

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Journal of Geriatric Cardiology 2011年第3期8卷 141-146页

作者： Christopher D Rolfes Stephen A Howard Ryan p Golf paul A Iaizzo Department of Biomedical Engineering University of Minnesota Minneapolis MAr 55455 USA Department of Surgery University of Minnesota Minneapolis MN55455 USA Department of Integrative Biology and physiology University of Minnesota Minneapolis MN 55455 USA

Background Atrial fibrillation （AF） causes a continuum of atrial anatomical remodeling. Methods Using a library of perfusion-fixed human hearts, specimens with AF were compared to controls. During this preliminary assessment study, direct measurements were taken of atrial volume, pulmonary vein （pV） circumference, and left atrial （LA） wall thicknesses. Results Hearts with AF typically had larger atrial volumes, as well as a much larger variation in volume compared to controls （range of 59.6-227.1 mL in AF hearts compared to 65.1-115.9 mL in controls）. For all hearts, right pVs were larger than left pVs （mean： 171.4 ± 84.6 mm^2 for right and 1182 ± 50.1 mm^2 for left, p 〈 0.005）. LA wall thicknesses ranged from 0.7 mm to 3.1 mm for both AF and control hearts. Conclusions Hearts with AF had a large range of sizes which is consistent with the progression of atrial remodeling during AF. The large range of thicknesses will influence the amount of energy needed to create transmural lesions during ablation procedures.

关键词： left atrial dimensions volumes pulmonary vein ostia atrial fibrillation

plant recruitment and survival as indicators of ecological restoration success in abandoned pasture land in Nurcoung,Victoria,Australia

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Ecological processes 2013年第1期2卷 380-392页

作者： Singarayer K Florentine Jessica Gardner Friedrich p Graz Sean Moloney School of Science Information Technology and Engineering Federation University AustraliaP.O.Box 663Mt.Helen 3353VICAustralia Greening Australia NC2 Building62 Main StreetNatimuk 3409Australia Department of Land Management Polytechnic of Namibia13Storch Str.P/Bag 13388WindhoekNamibia Department of Botany James Cook University1James Cook DrTownsville CityQLD 4811Australia

Introduction:One of the major impediments to developing better restoration strategies is the inadequate documentation of past restoration *** 2008,Greening Australia commenced ecological restoration on the Nurcoung property in Victoria to enhance local biodiversity,and in this paper we report on the habitat restoration outcomes in the three Ecological Vegetation Classes(EVC)found on this ***:permanent sample plots(12×20 m)were randomly established in July 2010 in each of the restoration areas,with 9,10,and 24 plots demarcated in Shallow Sands Woodland(SSW),Heathy Woodland(HW),and Sandstone Ridge Woodlands(SRW),*** plots were prepared to include three seeded *** were assessed for seedling recruitment and survival in May 2010,April 2011,and May *** of individual seedling development included their height and cover,and their location within the ***:Our study shows that interaction between the age of the planted and direct-seeded vegetation and the nature of the EVC significantly affects the composition of plants and the soil surface in that species and,further,that soil cover parameters develop in different ways in the different experimental plots.A SIMpER analysis of soil cover parameters shows that most of the variation over the years of restoration is attributable to differences in the amount of bare soil recorded,rather than the amount of leaf-litter cover,and that these changes in soil cover parameters differ between EVCs over the sampling *** direct-seeding study shows that whilst most of the broadcast species were recruited,some species used in the Shallow Sands Woodland,the Heathy Woodland,and the Sandstone Ridge Shrubland did not show evidence of recruitment during the three sampling *** the density of most seedlings increased in subsequent sampling years,the planted species Callitris gracilis,Callitris rhomboidea,Hakea muelleriana,and Melaleuca lanceolata did not ***

关键词： soil planted seedling

Veno occlusive disease: Update on clinical management

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World Journal of Gastroenterology 2007年第29期13卷 3918-3924页

作者： M Senzolo G Germani E Cholongitas p Burra AK Burroughs Gastroenterology Department of Surgical and Gastroenterological Sciences University Hospital of Padua Padua Italy Liver Transplantation and Hepatobiliary Unit Royal Free Hospital London United Kingdom

Hepatic veno-occlusive disease is a clinical syndrome characterized by hepatomegaly, ascites, weight gain and jaundice, due to sinusoidal congestion which can be caused by alkaloid ingestion, but the most frequent cause is haematopoietic stem cell transplantation （STC） and is also seen after solid organ transplantation. The incidence of veno occlusive disease （VOD） after STC ranges from 0 to 70%, but is decreasing. Survival is good when VOD is a mild form, but when it is severe and associated with an increase of hepatic venous pressure gradient 〉 20 mmHg, and mortality is about 90%. prevention remains the best therapeutic strategy, by using non-myeloablative conditioning regimens before STC. prophylactic administration of ursodeoxycholic add, being an antioxidant and antiapoptotic agent, can have some benefit in reducing overall mortality. Defibrotide, which has pro-fibrinolytic and antithrombotic properties, is the most effective therapy; decompression of the sinusoids by a b-ansjugular intrahepatic portosystemic shunt （TIpS） can be tried, especially to treat VOD after liver transplantation and when multiorgan failure （HOF） is not present. Liver transplantation can be the last option, but can not be considered a standard rescue therapy, because usually the concomitant presence of multiorgan failure contraindicates this procedure.

关键词： Veno occlusive disease Defibrotide Transjugular intrahepatic portosystemic shunt Liver transplantation

3eciphering the protein-DNA code of bacteria Ninged helix-turn-helix transcription factors

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Frontiers of Electrical and Electronic Engineering in China 2018年第1期6卷 68-84页

作者： Adam p. Joyce James J. Havranek program in Developmental Regenerative and Stem Cell Biology Washington University in St. Louis St. Louis MO 63110 USA Department of Biochemistry and Molecular Biophysics Washington University in St. Louis St. Louis MO 63110 USA

Background： Sequence-specific binding by transcription factors （TFs） plays a significant role in the selection and regulation of target genes. At the protein：DNA interface, amino acid side-chains construct a diverse physicochemical network of specific and non-specific interactions, and seemingly subtle changes in amino acid identity at certain positions may dramatically impact TF：DNA binding. Variation of these specificity-determining residues （SDRs） is a major mechanism of functional divergence between TFs with strong structural or sequence homology. Methods： In this study, we employed a combination of high-throughput specificity profiling by SELEX and Spec-seq, structural modeling, and evolutionary analysis to probe the binding preferences of winged helix-turn-helix TFs belonging to the OmpR sub-family in Escherichia coil Results： We found that E. coli OmpR paralogs recognize tandem, variably spaced repeats composed of＂GT-A＂ or ＂GCT＂-containing half-sites. Some divergent sequence preferences observed within the ＂GT-A＂ mode correlate with amino acid similarity; conversely, ＂GCT＂-based motifs were observed for a subset of paralogs with low sequence homology. Direct specificity profiling of a subset of OmpR homologues （CpxR, RstA, and OmpR） as well as predicted ＂SDR-swap＂ variants revealed that individual SDRs may impact sequence preferences locally through direct contact with DNA bases or distally via the DNA backbone. Conclusions： Overall, our work provides evidence for a common structural code for sequence-specific wHTH：DNA interactions, and demonstrates that surprisingly modest residue changes can enable recognition of highly divergent sequence motifs. Further examination of SDR predictions will likely reveal additional mechanisms controlling the evolutionary divergence of this important class of transcriptional regulators.

关键词： transcription factor SELEX winged helix-turn-helix specificity detenlainants two-component signaling

Metabolic plasticity of Nitrogen Assimilation by porphyra umbilicalis(Linnaeus) Kützing

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Journal of Ocean University of China 2012年第4期11卷 517-526页

作者： Jang K.Kim George p.Kraemer Charles Yarish Departments of Ecology and Evolutionary Biology and Marine Sciences University of Connecticut1 University PlaceStamfordCT 06901USA Department of Environmental Studies Purchase College735 Anderson Hill RoadPurchaseNY 10577USA

The physical stresses associated with emersion have long been considered major factors determining the vertical zona- tion of intertidal seaweeds. We examined porphyra umbilicalis （Linnaeus） Kiitzing thalli from the vertical extremes in elevation of an intertidal population （i.e. upper and lower intertidal zones） to determine whether porphyra thalli acclimate to different vertical elevations on the shore with different patterns of nitrate uptake and nitrate reductase （NR） and glutamine synthetase （GS） activities in response to different degrees of emersion stress. We found that the nitrate uptake and NR recovery in the emersed tissues took longer in lower intertidal sub-population than in upper intertidal sub-population; and GS activity was also significantly affected by emersion and, interestingly, such an activity was enhanced by emersion of thalli from both upper and lower intertidal zones. These results sug- gested that intta-population variability in post-emersion recovery of physiological functions such as nutrient uptake and NR activity enables local adaptation and contributes to the wide vertical distribution ofp. umbilicalis. The high GS activity during periodic emer- sion stress may be a protective mechanism enabling p umbilicalis to assimilate nitrogen quickly when it again becomes available, and may also be an evidence ofphotorespiration during emersion.

关键词： emersion glutamine synthetase nitrate reductase nitrogen assimilation porphyra