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RANS feasibility study of using roughness to mimic transition strip effect on the crossflowseparation over a 6:1 prolate-spheroid

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Journal of Hydrodynamics 2019年第3期31卷 570-581页

作者： Mojtaba M. Amiri marcelo A. Vitola Sergio H. Sphaier, Paulo T. Esperanza Ocean Technology Laboratory (LabOceano-COPPE) Federal University of Rio de Janeiro Rio de Janeiro RJ 21941-907 Brazil

An axisymmetric body at incidence experiences the three-dimensional crossflow separation. This separation is attributed to the adverse circumferential pressure gradient. However, the separation pattern is also dependent upon the structure of the boundary layer. In this regard, utilization of transition strip devices in experiments on axisymmetric bodies may modify this structure, and consequently the crossflow separation pattern. The main objective of the present research is to mimic numerically the transition strip effect on the crossflow separation over a 6:1 prolate-spheroid up to a = 30° incidence and ReL = 4.2 x 10&. However, to avoid direct modeling of the strip, which would increase the computational cost, an attempt was made to add roughness over the body surface. To estimate the roughness that simulates closely the transition strip effect, three different roughness values were considered. The numerical model is based on RANS and a Reynolds stress turbulence model implemented in STARCCM+. The simulations have been evaluated based on the local and global variables and validated against the available experimental data. The results demonstrate the effectiveness of using a proper roughness value to mimic the transition strip effect. They also show the importance of modeling the transition strip effect, which is normally not taken into account, to capture the crossflow separation pattern.

关键词： Axisymmetric body crossflow separation transition strip device CFD RANS equations

Effects of submergence in water on seed germination and vigor of the Copaifera lucens(Fabaceae) seedlings

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Journal of Forestry Research 2014年第4期25卷 903-908页

作者： Daniela Baldez Vidal Isis Leite Andrade Eusinia Louzada Pereira Andrade marcelo Schramm Mielke Department of Agricultural and Environmental Sciences State University of Santa Cruz BR 415 km 16 Ilhéus 45662-300 Bahia Brazil Department of Biological Sciences State University of Santa Cruz BR 415 km 16 Ilhéus 45662-300 Bahia Brazil

We analyzed the tolerance of Copaifera lucens seeds to sub- mersion in water to assess the use of this species for direct seeding in riparian forest restoration programs. Seeds were submerged in water for 2, 4, 8, 16 and 32 days or not submerged （control = 0 days of submer- gence）. For the control and at the end of each period of submersion, germination and seedling vigor tests were carried out. For germination tests, seeds were sown in plastic pots containing sand and kept in labora- tory conditions. The percentage of seed germination, the germination rate and the average germination time were analyzed. For seedlings, total biomass, leaf area, leaf mass per area and leaf area ratio were analyzed. Submersion time drastically affected the dissolved oxygen content and seed germination. Between 4 and 8 days of submersion there was a de- crease from 83.8% to 15.6% in the germination percentage. No seed germination occurred after 16 days of submersion. Although there was a significant decrease in the percentage of seed germination between 4 and 8 days of submersion, seedling vigor was not affected. Seeds of this species were partially tolerant to submersion in water, suggesting that C. lucens is a promising species for direct seeding in riparian forest restora- tion projects.

关键词： Copaiba Brazilian Atlantic Forest forest restoration germi-nation vigor

Relaxin prevents the development of severe acute pancreatitis

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World Journal of Gastroenterology 2006年第10期12卷 1558-1568页

作者： Laura Iris Cosen-Binker marcelo Gustavo Binker Rodica Cosen Gustavo Negri Osvaldo Tiscornia RHC-LICB Medical Research Institute-Buenos Aires Argentina Programa de Estudios Pancreáticos-Hospital de Clinicas Universidad de Buenos AiresArgentina Cátedra de Gastroenterologia y Enzimologia Clinica-Departamento de Bioquimica ClinicaFacultad de Farmacia y BioquimicaUniversidad de Buenos AiresArgentina RHC-LICB Medical Research Institute-Buenos Aires Argentina Programa de Estudios Pancreáticos-Hospital de Clínicas Universidad de Buenos AiresArgentina RHC-LICB Medical Research Institute-Buenos Aires Argentina Cátedra de Gastroenterología y Enzimología Clínica-Departamento de Bioquímica Clínica Facultad de Farmacia y Bioquimica Universidad de Buenos AiresArgentina Programa de Estudios Pancreáticos-Hospital de Clínicas Universidad de Buenos Aires Argentina

AIM： TO investigate the severity of acute pancreatitis （AP） is associated to the intensity of leukocyte activation, inflammatory up-regulation and microcirculatory disruption associated to ischernia-reperfusion injury. Hicrovascular integrity and inhibition of pro-inflammatory mediators are key-factors in the evolution of AP. Relaxin is an insulin-like hormone that has been attributed vasorelaxant properties via the nitric oxide pathway while behaving as a glucocorticoid receptor agonist. METHODS： AP was induced by the bilio-pancreatic duct-outlet-exclusion closed-duodenal-loops model. Treatment with relaxin was done at different timepoints. Nitric oxide synthase inhibition by L-NAME and glucocorticoid receptor （GR） blockage by mifepristone was considered. AP severity was assessed by biochemical and histopathological analyses. RESULTS： Treatment with relaxin reduced serum amylase, lipase, C-reactive protein, IL-6, IL-10, hsp72, LDH and 8-isoprostane as well as pancreatic and lung myeloperoxidase. Acinar and fat necrosis, hemorrhage and neutrophil infiltrate were also decreased. ATP depletion and ADP/ATP ratio were reduced while caspases 2-3-8 and 9 activities were increased. L-NAME and mifepristone decreased the efficiency of relaxin. CONCLUSION： Relaxin resulted beneficial in the treatment of AP combining the properties of a GR agonist while preserving the microcirculation and favoring apoptosis over necrosis.

关键词： Acute pancreatitis Relaxin Nitric oxide Glucocorticoid receptor Necrosis Apoptosis

Multipotent mesenchymal stromal cells:A promisingstrategy to manage alcoholic liver disease

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World Journal of Gastroenterology 2016年第1期22卷 24-36页

作者： Fernando Ezquer Flavia Bruna Sebastián Calligaris Paulette Conget marcelo Ezquer Centro de Medicina Regenerativa Facultad de MedicinaClínica Alemana-Universidad del DesarrolloSantiago 7710162Chile

Chronic alcohol consumption is a major cause of liver *** term alcoholic liver disease(ALD)refers to a spectrum of mild to severe disorders including steatosis,steatohepatitis,cirrhosis,and hepatocellular *** limited therapeutic options,stem cell therapy offers significant potential for these *** this article,we review the pathophysiologic features of ALD and the therapeutic mechanisms of multipotent mesenchymal stromal cells,also referred to as mesenchymal stem cells(MSCs),based on their potential to differentiate into hepatocytes,their immunomodulatory properties,their potential to promote residual hepatocyte regeneration,and their capacity to inhibit hepatic stellate *** perfect match between ALD pathogenesis and MSC therapeutic mechanisms,together with encouraging,available preclinical data,allow us to support the notion that MSC transplantation is a promising therapeutic strategy to manage ALD onset and progression.

关键词： Alcoholic liver disease Cellular therapy Alcoholic steatohepatitis Hepatic function recovery Mesenchymal stem cells

Skeletal muscle atrophy,regeneration,and dysfunction in heart failure:Impact of exercise training

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Journal of Sport and Health Science 2023年第5期12卷 557-567,F0003页

作者： Harrison Gallagher Paul W.Hendrickse marcelo G.Pereira T.Scott Bowen School of Biomedical Sciences Faculty of Biological SciencesUniversity of LeedsLeeds LS29JTUK

This review highlights some established and some more contemporary mechanisms responsible for heart failure(HF)-induced skeletal muscle wasting and *** first describe the effects of HF on the relationship between protein synthesis and degradation rates,which determine muscle mass,the involvement of the satellite cells for continual muscle regeneration,and changes in myofiber calcium homeostasis linked to contractile *** then highlight key mechanistic effects of both aerobic and resistance exercise training on skeletal muscle in HF and outline its application as a beneficial ***,HF causes multiple impairments related to autophagy,anabolic-catabolic signaling,satellite cell proliferation,and calcium homeostasis,which together promote fiber atrophy,contractile dysfunction,and impaired *** both wasting and weakness are partly rescued by aerobic and resistance exercise training in HF,the effects of satellite cell dynamics remain poorly explored.

关键词： Calcium Exercise training Heart failure Satellite cells Skeletal muscle wastingTagedAPTARAEnd

The effects of additive outliers in INAR(1) process and robust estimation

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Statistical Theory and Related Fields 2018年第2期2卷 206-214页

作者： marcelo Bourguignon Klaus L.P.Vasconcellos Departamento de Estatística Universidade Federal do Rio Grande do NorteNatalRNBrazil Departamento de Estatística Cidade UniversitáriaUniversidade Federal de PernambucoRecifePEBrazil

In this paper, methods based on ranks and signs for estimating the parameters of thefirst-order integer-valued autoregressive model in the presence of additive outliers are proposed. In particular, we use the robust sample autocorrelations based on ranks and signsto obtain estimators for the parameters of the Poisson INAR(1) process. The effects ofadditive outliers on the estimates of parameters of integer-valued time series are examined. Some numerical results of the estimators are presented with a discussion of theobtained results. The proposed methods are applied to a dataset concerning the numberof different IP addresses accessing the server of the pages of the Department of Statistics of the University of Würzburg. The results presented here give motivation to use themethodology in practical situations in which Poisson INAR(1) process contains additiveoutliers.

关键词： Additive outliers Poisson INAR(1)process robustness squared difference estimator

Lattice Boltzmann Modeling of Miscible Multicomponent Gas Mixtures in the Rarefied Regime

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Communications in Computational Physics 2022年第9期32卷 1179-1216页

作者： Michel Ho Sami Ammar Sebastien Leclaire marcelo Reggio Jean-Yves Trepanier Departement of Mechanical Engineering Polytechnique Montreal2500 Chemin de PolytechniqueMontreal H3T 1J4Canada

An extension to rarefied flow regimes of the lattice Boltzmann methodbased model for miscible mixtures developed by Vienne et al.(Physical Review E 100.2(2019):023309)is *** model is applied to study the gas phase separation phenomenon in mixture flows that traditional macroscopic approaches fail to *** extension includes a wall function approach with an empirical coefficient to define an effectivemean free path in solid geometries,which locally defines the kinematic viscosity and binary diffusion *** algorithm is also modified by a local multi-relaxation time collision operator and slip boundary conditions at solid *** mixture flow simulations are conducted through a 2D plane microchannel within the slip and early transition flow *** a miscible gaseous phase,the mixture loses its homogeneity and independent velocity profiles for each component are observed in the rarefied regime and captured with the current *** addition,the gas separation phenomenon increases with the rarefaction rate and the molecular mass *** individual treatment of the species within mixture flows in the developed lattice Boltzmann model helps understanding the increasing independent behavior of the individual specieswithin themixture as the regime becomesmore rarefied.

关键词： Lattice Boltzmann gaseous mixtures rarefied regimes

Challenge of liver disease in systemic lupus erythematosus:Clues for diagnosis and hints for pathogenesis

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World Journal of Hepatology 2014年第6期6卷 394-409页

作者： Ferno Bessone Natalia Poles marcelo G Roma Gastroenterology and Hepatology Department University of Rosario School of Medicine Institute of Experimental Physiology (CONI-CET-UNR) Faculty of Biochemical and Pharmaceutical SciencesUniversity of Rosario

Systemic lupus erythematosus(SLE) encompass a broad spectrum of liver diseases. We propose here to classify them as follows:(1) immunological comorbilities(overlap syndromes);(2) non-immunological comorbilities associated to SLE; and(3) a putative liver damage induced by SLE itself, referred to as "lupus hepatitis". In the first group, liver injury can be ascribed to overlapping hepatopathies triggered by autoimmune mechanisms other than SLE occurring with higher incidence in the context of lupus(e.g., autoimmune hepatitis, primary biliary cirrhosis). The second group includes non-autoimmune liver diseases, such as esteatosis, hepatitis C, hypercoagulation state-related liver lesions, hyperplasic parenchymal and vascular lesions, porphyria cutanea tarda, and drug-induced hepatotoxicity. Finally, the data in the literature to support the existence of a hepatic disease produced by SLE itself, or the occurrence of a SLE-associated prone condition that increases susceptibility to acquire other liver diseases, is critically discussed. The pathological mechanisms underlying each of these liver disorders are also reviewed. Despite the high heterogeneity in the literature regarding the prevalence of SLE-associated liver diseases and, in most cases, lack of histopathological evidence or clinical studies large enough to support their existence, it is becoming increasingly apparent that liver is an important target of SLE. Consequently, biochemical liver tests should be routinely carried out in SLE patients to discard liver disorders, particularly in those patients chronically exposed to potentially hepatotoxic drugs. Diagnosing liver disease in SLE patients is always challenging, and the systematization of the current information carried out in this review is expected to be of help both to attain a better understanding of pathogenesis and to build an appropriate work-up for diagnosis.

关键词： Systemic lupus erythematosus Lupus hepatitis Esteatosis Regenerative nodular hyperplasia Hepatitis C Autoimmune hepatitis Hepatotoxicity Nonsteroidal anti-inflammatory drugs Methotrexate

Follicular dendritic cell sarcoma of the liver:unusual presentation of a rare tumor and literature review

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Hepatobiliary & Pancreatic Diseases International 2011年第4期10卷 443-445页

作者： Paulo N Martins Sanjay Reddy Ann-Britt Martins marcelo Facciuto Department of Surgery Division of Hepatobiliary Surgery and TransplantationNew York Medical CollegeNew YorkUSA Department of Surgery New York Medical CollegeSt.Vincent's Catholic Medical CenterNew YorkUSA

BACKGROUND:Hepatic follicular dendritic cell (FDC) sarcoma is an extremely rare *** commonly,FDC sarcoma presents as a solitary mass in lymph nodes,however,several extra-nodal locations have been ***:We report a case of a 53-year-old female who presented with symptoms of abdominal pain,fever,anemia,and *** an extensive review of the literature,we have found only 12 cases of hepatic FDC ***:The tumor was 11.5 cm in diameter and composed of spindle and epithelioid cells with ovoid nuclei and associated with mixed inflammatory *** stains were positive for CD35 and *** patient underwent a left hepatic ***:Liver follicular dendritic cell sarcoma is a very rare *** cases present with abdominal pain and weight loss,and most of them can be managed by hepatic resection with excellent short-term outcomes.

关键词： follicular dendritic cell tumor liver neoplasms sarcoma jaundice