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A Discontinuous Galerkin Extension of the Vertex-Centered Edge-Based Finite Volume Method

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Communications in Computational Physics 2009年第2期5卷 456-468页

作者： Martin Berggren sven-Erik Ekstrom Jan Nordstrom Department of Computing Science Ume˚a UniversitySE-90187 Ume˚a Sweden Division of Scientific Computing Department of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden

The finite volume(FV)method is the dominating discretization technique for computational fluid dynamics(CFD),particularly in the case of compressible *** discontinuous Galerkin(DG)method has emerged as a promising highaccuracy *** standard DG method reduces to a cell-centered FV method at lowest ***,many of today’s CFD codes use a vertex-centered FV method in which the data structures are edge *** develop a new DG method that reduces to the vertex-centered FV method at lowest order,and examine here the new scheme for scalar hyperbolic ***,the method shows optimal-order accuracy for a smooth linear *** applying a basic hp-adaption strategy,the method successfully handles *** also discuss how to extend the FV edge-based data structure to support the new *** this way,it will in principle be possible to extend an existing code employing the vertex-centered and edge-based FV discretization to encompass higher accuracy through the new DG method.

关键词： Discontinuous Galerkin methods finite volume methods dual mesh vertex-centered edge-based CFD

Does DE need a C?A proposal for a DE curriculum

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International Journal of Digital Earth 2014年第1期7卷 88-92页

作者： Tim Foresman sven Schade Yola Georgiadou Josef Strobl International Center for Remote Sensing Education BaltimoreMDUSA Shared Environmental Information System(SEIS)Support Program European Environment AgencyCopenhagenDenmark Faculty of Geo-Information Science and Earth Observation(ITC) University of TwenteEnschedeThe Netherlands Department of Geoinformatics Z_GIS University of SalzburgSalzburgAustria

The vision of a digital earth(DE)is continuously evolving,and the next-generation infrastructures,platforms and applications are being *** this article,we attempt to initiate a debate within the DE and with affine communities about‘why’a digital earth curriculum(DEC)is needed,‘how’it should be developed,and‘what’it could look *** is impossible to do justice to the Herculean effort of DEC development without extensive consultations with the broader *** propose a frame for the debate(what,why,and how of a DEC)and a rationale for and elements of a curriculum for educating the coming generations of digital natives and indicate possible *** particularly argue that a DEC is not a déjàvu of classical research and training agendas of geographic information science,remote sensing,and similar fields by emphasizing its unique characteristics.

关键词： learning education teaching training curriculum

The effect of adenovirus expressing wild-type p53 on 5-fluorouracil chemosensitivity is related to p53 status in pancreatic cancer cell lines

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World Journal of Gastroenterology 2004年第24期10卷 3583-3589页

作者： sven Eisold Michael Linnebacher EduardRyschich DaliborAntolovic UlfHinz Ernst Klar Jan Schmidt Department of General Surgery Thoracic and Vascular SurgeryUniversity of RostockSchillingallee 35D-18057 RostockGermany Molecular Pathology University of HeidelbergINFD-68120 HeidelbergGermany Department of General Surgery University of HeidelbergINFD-69120 HeidelbergGermany

AIM:There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU). Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53 gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status. METHODS:Human pancreatic cancer cell lines Capan-1^(p53mut), Capan-2^(p53wt),FAMPAC^(p53mut),PANC1^(p53mut),and rat pancreatic cancer cell lines AS^(p53wt) and DSL6A^(p53null) were used for in vitro *** infection with different ratios of Ad- p53-particles (MOI) in combination with 5-FU,proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining).In addition,DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivo studies. Tumor size,apoptosis (TUNEL) and survival were determined. RESULTS:Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing *** vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus *** in vitro and in vivo analyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU. CONCLUSION:Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 *** findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.

关键词： Adenoviridae Adult Animals Antimetabolites, Antineoplastic Apoptosis Cell Division Cell Line, Tumor Combined Modality Therapy Drug Resistance, Neoplasm Female Fluorouracil Gene Expression Regulation, Neoplastic Gene Therapy Humans In Vitro Male Pancreatic Neoplasms Rats Rats, Inbred Lew Transduction, Genetic Tumor Suppressor Protein p53

Digital Earth’s Nervous System for crisis events:real-time Sensor Web Enablement of Volunteered Geographic Information

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International Journal of Digital Earth 2010年第3期3卷 242-259页

作者： Bertrand De Longueville Alessandro Annoni sven Schade Nicole Ostlaender Ceri Whitmore Institute for Environment and Sustainability Joint Research Centrevia E.Fermi1T.P.262Ispra 21020Italy

Digital Earth(DE)is a powerful metaphor for the organisation and access to digital information through a multi-scale three-dimensional representation of the *** progress gave a concrete body to this ***,this body is not yet self-aware:further integration of the temporal and voluntary dimension is needed to better portray the event-based nature of our *** thus aim to extend DE vision with a Nervous System in order to provide decision makers with improved alerting *** applications are foreseen for crisis management,where up-to-date situational awareness is *** it is traditionally built through trusted sources,citizens can play a complementary role by providing geo-referenced information known as Volunteered Geographic Information(VGI).Although workflows have been implemented to create,validate and distribute VGI datasets for various thematic domains,its exploitation in real time and its integration into existing concepts of DE,such as spatial data infrastructures,still needs to be further *** this paper we suggest to bridge this gap through Sensor Web Enablement for VGI,where VGI sensing becomes a sense of the DE’s Nervous *** discuss this approach and its applicability in the context of a forest fire scenario.

关键词： sensor web VGI SDI crisis Digital Earth’s Nervous System

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World Journal of Gastroenterology 2007年第1期13卷 152-157页

作者： Berit Baum Felix Meneses sven Kleinschmidt Ingo Nolte Marion Hewicker-Trautwein Department of Pathology University of Veterinary Medicine Hannover Germany Clinic for Small Animals University of Veterinary Medicine Hannover Germany

AIM： To examine the of the gastric, jejuna physiological aging. changes in the histomorphology and colonic wall of dogs due to METHODS： Full thickness biopsies were taken from the gastrointestinal tracts of 28 dogs of different ages. The thickness of the different layers of the wall was measured and the numbers of proliferating cells as indicated by immunohistochemical detection of Ki67 were counted. RESULTS： In the three excision sites, the thickness of all subepithelial layers increased with rising age. The strongest correlation between age and thickness of the intestinal wall was found in the first 10 years of life and in the jejunum （r =0.6-0.71 for the deep lamina propria mucosa, the muscularis mucosa, and the circular layer of the tunica muscularis）. The number of proliferating cells decreased during aging, with the strongest correlation in the lamina propria mucosa and lamina muscularis mucosa of the jejunum and in the colonic submucosa （r =-0.61 to -0.71）. Epithelial proliferation was only weakly correlated to the age. CONCLUSION： The morphology of the deeper layers and the proliferation of mesenchymal cells of the intestinal wall of healthy dogs are correlated with age. Gastrointestinal epithelial proliferation is only weakly age-correlated.

关键词： Age, Canine, Intestine Ki67 Stomach

Liver surgery in cirrhosis and portal hypertension

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World Journal of Gastroenterology 2016年第9期22卷 2725-2735页

作者： Christina Hackl Hans J Schlitt Philipp Renner sven A Lang Department of Surgery University Medical Center Regensburg

The prevalence of hepatic cirrhosis in Europe and the United States, currently 250 patients per 100000 inhabitants, is steadily increasing. Thus, we observe a significant increase in patients with cirrhosis and portal hypertension needing liver resections for primary ormetastatic lesions. However, extended liver resections in patients with underlying hepatic cirrhosis and portal hypertension still represent a medical challenge in regard to perioperative morbidity, surgical management and postoperative outcome. The Barcelona Clinic Liver Cancer classification recommends to restrict curative liver resections for hepatocellular carcinoma in cirrhotic patients to early tumor stages in patients with Child A cirrhosis not showing portal hypertension. However, during the last two decades, relevant improvements in preoperative diagnostic, perioperative hepatologic and intensive care management as well as in surgical techniques during hepatic resections have rendered even extended liver resections in higher-degree cirrhotic patients with portal hypertension possible. However, there are few standard indications for hepatic resections in cirrhotic patients and risk stratifications have to be performed in an interdisciplinary setting for each individual patient. We here review the indications, the preoperative risk-stratifications, the morbidity and the mortality of extended resections for primary and metastatic lesions in cirrhotic livers. Furthermore, we provide a review of literature on perioperative management in cirrhotic patients needing extrahepatic abdominal surgery and an overview of surgical options in the treatment of hepatic cirrhosis.

关键词： Liver resection Hepatocellular carcinoma Liver metastases Portal hypertension Cholangiocellular carcinoma Cirrhosis

Brain natriuretic peptide is a potent vasodilator in aged human microcircula- tion and shows a blunted response in heart failure patients

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Journal of Geriatric Cardiology 2014年第1期11卷 50-56页

作者： Marie-Louise Edvinsson Erik Uddman Lars Edvinsson sven E. Andersson Department of Emergency and Internal Medicine Institute of Clinical Sciences Lund University Lund University Hospital SE- 221 85 Lund Sweden

Background Brain natriuretic peptide （BNP） is normally present in low levels in the circulation, but it is elevated in parallel with the degree of congestion in heart failure subjects （CHF）. BNP has natriuretic effects and is a potent vasodilator. It is suggested that BNP could be a therapeutic alternative in CHF. However, we postulated that the high levels of circulating BNP in CHF may downregulate the response of microvascular natriuretic receptors. This was tested by comparing 15 CHF patients （BNP 〉 3000 ng/L） with 10 matched, healthy controls. Methods Cutaneous microvascular blood flow in the forearm was measured by laser Doppler Flowmetry. Local heating （＋44°C, 10 min） was used to evoke a maximum local dilator response. Results Non-invasive iontophoretic administration of either BNP or acetylcholine （ACh）, a known endothelium-dependent dilator, elicited an increase in local flow. The nitric oxide synthase inhibitor, l-N-Arginine- methyl-ester （L-NAME）, blocked the BNP response （in controls）. Interestingly, responses to BNP in CHF patients were reduced to about one third of those seen in healthy controls （increase in flow： 251% in CHF vs. 908% in controls; P 〈 0.001）. In contrast, the vasodilator responses to ACh and to local heating were only somewhat attenuated in CHF patients. Thus, dilator capacity and nitric oxide signalling were not af- fected to the same extent as BNP-mediated dilation, indicating a specific downregulation of the latter response. Conclusions The findings show for the first time that microvascular responses to BNP are markedly reduced in CHF patients. This is consistent with the hypothesis of BNP receptor function is downregulated in CHF.

关键词： Heart failure Cutaneous microcirculation Endothelial responses Acetylcholine, Brain natriuretic peptide Nitric oxide

Dual-sugar tests of small intestinal permeability are poor predictors of bacterial infections and mortality in cirrhosis: a prospective study

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World Journal of Gastroenterology 2016年第11期22卷 3275-3284页

作者： Anika Vogt Philipp A Reuken sven Stengel Andreas Stallmach Tony Bruns Department of Internal Medicine IV (Gastroenterology Hepatologyand Infectious Diseases)Jena University Hospital Center for Sepsis Control and Care Jena University Hospital

AIM: To prospectively analyze the impact of increased intestinal permeability (IP) on mortality and the occurrence of infections in patients with ***: IP was quantified using the lactulose/mannitol (L/M) test in 46 hospitalized patients with cirrhosis (25 Child-Pugh A/B, 21 Child-Pugh C) and in 16 healthy controls. Markers of inflammation [LPS-binding protein, Interleukin-6 (IL-6)] and enterocyte death [intestinal fatty-acid binding protein (I-FABP)] were determined in serum using enzyme-linked immunosorbent assays. Patients were followed for one year and assessed for survival, liver transplantation, the necessity of hospitalization and the occurrence of bacterial infections. The primary endpoint of the study was defined as differences in survival between patients with pathological and without pathological lactulose/mannitol ***: Thirty-nine (85%) patients with cirrhosis had a pathologically increased IP index (L/M ratio > 0.07) compared to 4 (25%) healthy controls (P < 0.0001). The IP index correlated with the Child-Pugh score (r = 0.484, P = 0.001) and with serum IL-6 (r = 0.342, P = 0.02). Within one year, nineteen (41%) patients developed a total of 33 episodes of hospitalization with bacterial or fungal infections. Although patients who developed spontaneous bacterial peritonitis (SBP) (n = 7) had a higher IP index than patients who did not (0.27 vs 0.14, P = 0.018), the baseline IP index did not predict time to infection, infection-free survival or overall survival, neither when assessed as linear variable, as tertiles, nor dichotomized using an established cut-off. In contrast, model for end-stage liver disease score, Child-Pugh score, the presence of ascites, serum IL-6 and I-FABP were univariate predictors of infection-free ***: Although increased IP is a frequent phenomenon in advanced cirrhosis and may predispose to SBP, it failed to predict infection-free and overall survival in this prospective coho

关键词： Intestinal permeability Liver cirrhosis Lactulose/mannitol ratio Spontaneous bacterial peritonitis Bacterial translocation

Changes of the liver metabolome following an intravenous lipopolysaccharide injection in Holstein cows supplemented with dietary carnitine

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Journal of Animal Science and Biotechnology 2023年第1期14卷 188-199页

作者： Wei Xu Sandra Grindler Akos Kenez sven Danicke Jana Frahm Korinna Huber Beijing Research Center of Intelligent Equipment for Agriculture Beijing 100097China. Department of Biosystems Biosystems Technology ClusterCampus GeelKleinhoefstraat 42440 Geel LeuvenKUBelgium. Institute of Animal Science Faculty of Agricultural SciencesUniversity of Hohenheim70599 StuttgartGermany. Department of Infectious Diseases and Public Health City University of Hong KongBlock 14/FTo Yuen Building31 To Yuen StreetKowloonHong Kong SARChina. Institute of Animal Nutrition Federal Research Institute for Animal Health(Friedrich-Loeffler-Institut)38116 BrunswickGermany.

Background:Carnitine facilitates the flux of long-chain fatty acids for hepatic mitochondrial beta-oxidation,which acts to ameliorate the negative energy balance commonly affecting high-yielding dairy *** triggered by lipopolysaccharide(LPS)load can however pose a challenge to the metabolic integrity via the expression of pro-inflammatory mediators,leading to immune system activation and respective metabolic *** effect of enhanced carnitine availability on hepatic metabolome profiles during an inflammatory challenge has not yet been determined in dairy ***,Holstein cows were supplemented with 25 g/d rumen-protected carnitine from 42d prepartum until 126 d postpartum(n=16)or assigned to the control group with no supplementation during the same period(n=14).We biopsied the liver of the cows before(100 d postpartum)and after(112 d postpartum)an intravenous injection of 0.5μg/kg *** samples were subjected to a targeted metabolomics analysis using the AbsoluteIDQ p180 Kit(Biocrates Life Sciences AG,Innsbruck,Austria).Results:Multivariate statistical analyses revealed that hepatic metabolome profiles changed in relation to both the carnitine supplementation and the LPS *** the metabolite profiles on 100 d,carnitine increased the concentration of short-and long-chain acyl-carnitines,which may be explained by an enhanced mitochondrial fatty acid shuttle and hence greater energy *** LPS injection affected hepatic metabolite profiles only in the carnitine supplemented group,particularly altering the concentration of biogenic ***:Our results point to interactions between an acute hepatic inflammatory response and biogenic amine metabolism,depending on energy availability.

关键词： Acyl-carnitines Inflammatory response Lipid metabolism Liver metabolome Mitochondrial function