bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrated Modelling with COCONUT of Type‐I ELMs at JET
Authors: Wiesen S. , Parail V. , Corrigan G. , Fundamenski W. , Loarte A. , Lönnroth J. , Saibene G. , Sartori R. , JET EFDA Contributors  
Published: March 2008

AbstractWhen modelling ELMy H‐mode plasmas the strong interaction between the core plasma and the scrape‐offlayer (SOL) must be accounted for. The 1.5D core code JETTO [1] and the 2D SOL fluid‐code EDGE2D [2] have been combined to provide a consistent picture of the transport across the separatrix, resulted in the coupled code COCONUT [3]. The ELM‐crash itself is modelled in an ad hoc manner, by which the perpendicular diffusive transport within the ETB is enhanced for a short time (≈ few 100 μs). An ELM is triggered if the normalised pressure gradient exceeds a critical threshold, αc , specified by the MHD‐stability analysis [4]. COCONUT simulations indicate that the neutral penetration changes the ETB transport behaviour qualitatively such as it reduces convection [5]. But since the same power enters the ETB from the core, a reduction in the convected out.ux to the SOL leads to a peak in the radial pressure gradient profile earlier in the ELM cycle. As a consequence, the ELM frequency increases, a tendency which is indeed seen in experiment. This paper concentrates on the modelling of type‐I ELMy H‐mode, pure‐D JET plasmas, seeking to match experimental results for different scans of gas‐puff, pedestal parameters (such as nped , Tped and ν *ped ). The effects on ELM frequency, power‐exhaust, a detailed analysis of the time‐dependence of ELM‐crashes and the reformation of the pedestal are discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Progress in Kinetic Simulation of Edge Plasmas
Authors: Cohen R. H. , Xu X. Q. 
Published: March 2008

AbstractKinetic codes are required for quantitative simulation of edge plasmas of most tokamaks, because orbit widths can be comparable to radial scale lengths and because mean free paths can be comparable to scale lengths along the magnetic field. However, the edge presents special challenges for edge simulation, both in terms of formulation and implementation. There are two major approaches to kinetic simulation, namely particle‐based and continuum‐ (high‐dimensional fluid‐) based. The edge presents challenges common to both approaches as well as ones that are unique to each approach. In this paper we review these challenges, and survey how they are being addressed in current edge kinetic simulation projects, as well as the status and accomplishments of those projects. We discuss in some detail the status and recent accomplishments of the U.S. Edge Simulation Laboratory (ESL), a project based on the continuum approach. The ESL currently consists of a main‐line effort to develop a code based on high‐order conservative finite‐volume discretization, as well as two prototype activities, TEMPEST and EGK. These prototype codes are exploring issues attached to energy‐magnetic moment and parallel velocity‐magnetic moment representations, respectively, as well as physics issues associated with simulation in a steep radial gradient region and a domain that includes both open field lines and closed flux surfaces. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Molecular Dynamics Simulation of Hydrogen Isotope Injection into Graphene
Authors: Nakamura H. , Takayama A. , Ito A. 
Published: March 2008

AbstractWe reveal the hydrogen isotope effect of three interactions, i.e, the reflection, the adsorption and the penetration ratios, by classical molecular dynamics simulation with a modified Brenner's reactive empirical bond order (REBO) potential potential. We find that the reflection by π ‐electron does not depend on the mass of the incident isotope, but the peak of the reflection by nuclear moves to higher side of incident energy. In addition to the reflection, we also find that the adsorption ratio in the positive z side of the graphene becomes larger, as the mass of the incident isotope becomes larger. On the other hand, the adsorption ratio in the negative z side of the graphene becomes smaller. Last, it is found that the penetration ratio hardly depends on the mass of the incident isotope because the graphene potential is not affected by the mass. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of Hydrocarbon Redeposition on Plasma Shadowed Areas
Authors: Inai K. , Ohya K. 
Published: March 2008

AbstractIn order to investigate tritium co‐deposition in the gaps between divertor tiles and the shadowed areas from the step structure of neighboring tiles, a hydrocarbon transport code is combined with castellated structure surface models. The hydrocarbons are easily reflected on the surface and transported in the plasma, with some reaching the gap between the tiles where it is difficult for them to escape, even if they are reflected at the side surfaces. The tile surface is inclined to vary the shadowed area. At a high plasma temperature with increasing inclination angle, the co‐deposition in the gap is strongly suppressed whereas most hydrocarbons are deposited on the shadowed area of the tile, which gradually increases. Consequently, there is an inclination angle for which the co‐deposition is minimized. Furthermore the net redeposition rate of hydrocarbons released from the tile surface in the gaps is estimated for different gap widths and tile areas. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ghrelin: a new peptide regulating the neurohormonal system, energy homeostasis and glucose metabolism
Authors: Pusztai Peter , Sarman Beatrix , Ruzicska Eva , Toke Judit , Racz Karoly , Somogyi Aniko , Tulassay Zsolt 
Published: March 2008

AbstractIdentification of ghrelin started with the discovery of growth hormone secretagogues, continued with the description of ghrelin receptors and ended with the elucidation of the chemical structure of ghrelin. However, several issues concerning the role of ghrelin in physiological and pathophysiological processes are still under investigation. Most of the ghrelin produced in the body is secreted in the stomach, but it is also expressed in the hypothalamus, pituitary, pancreas, intestine, kidney, heart and gonads. Ghrelin stimulates growth hormone secretion via growth hormone secretagogue receptors. Ghrelin secretion in the stomach depends on both acute and chronic changes in nutritional status and energy balance. Current data support the hypothesis that the stomach, in addition to its important role in digestion, not only influences pituitary hormone secretion but, via ghrelin production, it also sends orexigenic (appetite increasing) signals to hypothalamic nuclei involved in the regulation of energy homeostasis. In addition to these main effects, ghrelin influences insulin secretion and glucose metabolism and it may exert potentially important effects on cardiovascular and gastrointestinal functions. Because of its effects on a large number of physiological functions, ghrelin may be involved in the pathomechanism of several human disorders, including disturbances of appetite, energy homeostasis and glucose metabolism. Further research might lead to a better understanding of the pathophysiology of ghrelin and might provide more effective therapy for the above disorders. Copyright © 2008 John Wiley & Sons, Ltd.
Viruses induce high expression of BAFF by salivary gland epithelial cells through TLR‐ and type‐I IFN‐dependent and ‐independent pathways
Authors: Ittah Marc , Miceli‐Richard Corinne , Gottenberg Jacques‐Eric , Sellam Jérémie , Eid Pierre , Lebon Pierre , Pallier Coralie , Lepajolec Christine , Mariette Xavier 
Published: March 2008

AbstractB cell activating factor (BAFF) plays a key role in promoting B lymphocyte activation. We investigated whether danger signals induce BAFF secretion by cultured salivary gland epithelial cells (SGEC), which are the target of primary Sjögren's syndrome, a prototypic systemic autoimmune disease. SGEC cultures were established from minor salivary glands obtained from ten patients with pSS or sicca symptoms. BAFF mRNA and protein were measured after stimulation of the different Toll‐like receptors (TLR) by agonists or viruses. The expression of TLR2, –3, and –7 was detected in SGEC. Poly (I:C) (a synthetic TLR3 agonist) and reovirus‐1 (a dsRNA virus) induced high expression of BAFF mRNA (multiplied by a factor of 246 ± 39 (SEM) and 347 ± 66, respectively) and of BAFF protein secretion (58.49 ± 4.34 pg/mL and 69.73 ± 5.67). Inhibition of both the endosomal (by chloroquine) and IFN (by anti‐IFNAR antibody) pathways partly inhibited BAFF expression. Treatment with both dsRNA virus and poly (I:C) induced high levels of BAFF mRNA and protein expression by SGEC, through pathways dependent on and independent of TLR and dependent on and independent of IFN. BAFF induction by target organs of autoimmune diseases after viral infection may be a link between innate immunity and autoimmunity.
AMP‐activated protein kinase regulates lymphocyte responses to metabolic stress but is largely dispensable for immune cell development and function
Authors: Mayer Alice , Denanglaire Sébastien , Viollet Benoit , Leo Oberdan , Andris Fabienne 
Published: March 2008

AbstractAMP‐activated protein kinase (AMPK), a phylogenetically conserved serine/threonine protein kinase, represents an energy sensor able to adapt cellular metabolism in response to nutritional environmental variations. TCR stimulation activates AMPK, a regulatory event that is known to stimulate ATP‐producing processes, possibly in anticipation of the increased energetic needs associated with cell division and expression of effector function. Taking advantage of the selective expression of the AMPKα1 catalytic subunit in lymphoid cells, we have analyzed the in vitro and in vivo capacity of lymphocytes lacking AMPK activity (AMPKα1‐KO cells) to respond to metabolic stress and to initiate and sustain an immune response. AMPKα1‐KO cells displayed increasing sensitivity to energetic stress in vitro, and were found unable to maintain adequate ATP levels in response to ATP synthase inhibition. These cells were, however, able to respond to antigen stimulation in vitro, as shown by optimal proliferation and cytokine production. Similarly, AMPKα1‐KO mice were fully immunocompetent in vivo and displayed normal cell proliferation, humoral, cytotoxic and delayed‐type hypersensitivity (DTH) responses following antigen injection. In conclusion, AMPK represents an important enzyme allowing lymphocytes to resist a mild energy crisis in vitro, but is largely dispensable for activation and expression of effector function in response to antigen stimulation.
Coxiella burnetii, the agent of Q fever, stimulates an atypical M2 activation program in human macrophages
Authors: Benoit Marie , Barbarat Bernadette , Bernard Alain , Olive Daniel , Mege Jean‐Louis 
Published: March 2008

AbstractCoxiella burnetii is an obligate intracellular bacterium, responsible for Q fever, which survives in macrophages by interfering with their microbicidal competence. As functional polarization of macrophages is critical for their microbicidal activity, we studied the activation program of monocyte‐derived macrophages (MDM) stimulated with C. burnetii. This program was markedly distinct from that induced by lipopolysaccharides (LPS), a canonical inducer of M1 polarization. Indeed, C. burnetii up‐regulated the expression of genes associated with M2 polarization, including TGF‐β1, IL‐1 receptor antagonist (IL‐1ra), CCL18, the mannose receptor and arginase‐1, and only up‐regulated the expression of two genes associated with M1 polarization, namely IL‐6 and CXCL8. In contrast, C. burnetii down‐regulated the expression of genes associated with M1 polarization such as TNF, CD80, CCR7 and TLR‐2. Functional analyses showed that C. burnetii‐stimulated MDM produced high levels of TGF‐β1 and CCL18, and expressed the mannose receptor and arginase‐1, the latter being associated with the prevention of nitric oxide production by MDM. Finally, C. burnetii induced the release of IL‐6 and CXCL8 at a lower level than LPS‐stimulated MDM. Our results suggest that C. burnetii stimulated an atypical M2 activation program that may account for the persistence of C. burnetii in macrophages.Supporting Information for this article is available at http://www.wiley‐vch.de/contents/jc_2040/2008/37917_s.pdf
Electrochemical Biosensors for Medical and Food Applications
Authors: Ahmed Minhaz Uddin , Hossain Mohammad Mosharraf , Tamiya Eiichi 
Published: March 2008

AbstractSensing and quantification of DNA and proteins are becoming increasingly important in biochemistry, medicine and biotechnology. Traditional analytical techniques are lagging behind the demand for more information in less time, at a lower cost. An important step forward in this pursuit is to identify an analyte using its electrochemical behavior and to convert its presence and concentration into perceivable and distinct electrical signals. This review covers the strategies for electrochemical sensing of biomolecules, mainly, DNA and proteins by label‐based and label‐free approaches using disposable electrochemical printed chips and carbon nanotube based field effect transistors. Issues, such as ease of preparation, robustness, sensitivity, and realization of mass production of the detection strategies are also considered. A good coverage of the published literature, mostly, a wide treatment of original research articles reporting novel principles has been made. Finally, this review may help the researchers in developing an understanding of miniaturized electrochemical biosensors and their possible applications in medical and food science, with directions for future research.
Determination of organic anions in atmospheric aerosol samples by capillary electrophoresis after reversed pre‐electrophoresis
Authors: Blanco‐Heras Gustavo A. , Turnes‐Carou M. Isabel , López‐Mahía Purificación , Muniategui‐Lorenzo Soledad , Prada‐Rodríguez Darío , Fernández‐Fernández Esther 
Published: March 2008

AbstractThis work presents the determination of low‐molecular‐mass (LMM) organic acids by CE after extraction with MeOH and preconcentration by evaporation. The interference arising from the simultaneous concentration of fast mobile anions (chloride, nitrate, and sulfate) at levels 200 times higher than those of LMM organic acids was reduced by the application of reversed pre‐electrophoresis (RPE) as clean‐up technique. This methodology allows for an effective elimination of high levels of fast mobile anions from the capillary before the separation has taken place, although analytes are also partially eliminated according to their electrophoretic velocities. In order to achieve an accurate quantification of organic anions, the use of a mathematical correction based on the linear relation between the analyte's effective volume removed during RPE and its mobility is proposed. Methods based on the use of one and two internal standards are discussed and evaluated. The proposed method is applied to the determination of organic acids in atmospheric particulate matter samples.
Multiphase non‐Newtonian effects on pulsatile hemodynamics in a coronary artery
Authors: Kim Yong Hyun , VandeVord Pamela J. , Lee Joon Sang 
Published: March 2008

AbstractHemodynamic stresses are involved in the development and progression of vascular diseases. This study investigates the influence of mechanical factors on the hemodynamics of the curved coronary artery in an attempt to identify critical factors of non‐Newtonian models. Multiphase non‐Newtonian fluid simulations of pulsatile flow were performed and compared with the standard Newtonian fluid models. Different inlet hematocrit levels were used with the simulations to analyze the relationship that hematocrit levels have with red blood cell (RBC) viscosity, shear stress, velocity, and secondary flow. Our results demonstrated that high hematocrit levels induce secondary flow on the inside curvature of the vessel. In addition, RBC viscosity and wall shear stress (WSS) vary as a function of hematocrit level. Low WSS was found to be associated with areas of high hematocrit. These results describe how RBCs interact with the curvature of artery walls. It is concluded that although all models have a good approximation in blood behavior, the multiphase non‐Newtonian viscosity model is optimal to demonstrate effects of changes in hematocrit. They provide a better stimulation of realistic blood flow analysis. Copyright © 2008 John Wiley & Sons, Ltd.
Development and Characterisation of Electrically Conductive Polymeric‐Based Blends for Proton Exchange Membrane Fuel Cell Bipolar Plates
Authors: Bouatia S. , Mighri F. , Bousmina M. 
Published: March 2008

AbstractThe main objective of this work was to develop films with controlled dimensions for proton exchange membrane fuel cell (PEMFC) bipolar plates (BPPs) using the twin‐screw extrusion process. These films consisted of a low‐viscosity polyethylene terephthalate (PET) in which a mixture of high specific surface area carbon black (CB) and synthetic flake graphite (GR) were dispersed. A third conductive additive, consisting of silver‐coated glass particles (SCG) or multi‐walled carbon nanotubes (MWCNT), was also added at a low concentration (5 wt.‐%) in order to study its synergistic effect on the PET‐based blend electrical conductivity. As the developed blends had to meet properties suitable for PEMFC bipolar plate applications, they were characterised for their electrical through‐plane resistivity, mechanical properties and oxygen permeability. Through‐plane electrical resistivity of about 0.3 Ω·cm and oxygen permeation rate of 3.5 × 10–8 cc cm–2 s–1 were obtained for only 30 wt.‐% of a 60:40 mixture of CB/GR conductive additives. Although the substitution of 5 wt.‐% of CB/GR by the same amount of MWCNT had no significant effect on BPPs' electrical resistivity, it helped to improve their mechanical properties and especially their oxygen permeation, which was decreased from 3.5 × 10–8 cc cm–2 s–1 to around 0.6 × 10–8 cc cm–2 s–1.
Development of a two‐dimensional finite element model for inundation processes in the Tonle Sap and its environs
Authors: Hai Pham Thanh , Masumoto Takao , Shimizu Katsuyuki 
Published: March 2008

AbstractA hydrodynamic model, which covers the floodplains of the Mekong River from Kratie in Cambodia to near the Vietnamese border, was developed using a finite element method (FEM) with 2D shallow‐water equations. The model was applied to typical flows of recent largest (2000) and smallest (2003) flood years. Main roads, dikes, colmatages, and road‐opening works in the study area, which may influence flow regimes, were introduced into the simulation. Moving boundary problems were accommodated by applying a threshold technique in which nodes having a thin water depth were reset to dry ones in all moving boundary elements at every time increment. Simulated results and available observed water levels and discharges were compared to validate the model. The simulated results produced a lot of hydrologic data for the basin areas, without gauging, and these data can be used to evaluate the effects of basin management on flooding and agricultural water use. Copyright © 2008 John Wiley & Sons, Ltd.
Cellular immune response from chagasic patients to CRA or FRA recombinant antigens of Trypanosoma cruzi
Authors: Lorena Virginia M.B. , Verçosa Alinne F.A. , Machado Raquel C.A. , Moitinho‐Silva Lucas , Cavalcanti Maria G.A. , Silva Edimilson D. , Ferreira Antonio G.P. , Correa‐Oliveira Rodrigo , Pereira Valéria R.A. , Gomes Yara M. 
Published: March 2008

AbstractWe propose to analyze the relation between the cellular immune response of Chagas' disease patients after in vitro stimulation of peripheral blood mononuclear cells (PBMC) with recombinant antigens cytoplasmatic repetitive antigen (CRA) or flagellar repetitive antigen (FRA) of T. cruzi and the chronic clinical forms of disease. Cells were stimulated using phytohemagglutinin, CRA, FRA, or a soluble antigen of Epimastigota (Ag‐Epi) for 24 hr, 72 hr, or 6 days. The proliferation of cells was evaluated after 6 days of culture by quantification of incorporated 3H‐thymidine. Cytokines were measured in the supernatants obtained after 24 hr (tumor necrosis factor [TNF]‐α and interleukin [IL]‐4), 72 hr (IL‐10), and 6 days (interferon [IFN]‐γ) using enzyme‐linked immunosorbent assay (ELISA). Cells of the Chagas patients stimulated with the recombinant antigens exhibited higher proliferation responses compared with that of non‐Chagas (NC) individuals. However, when proliferation was compared between patients with the cardiac form (CF) or indeterminate form (IF), it was not possible to establish a difference in the response. So far as the cytokines secreted in the culture supernatants after stimulation in vitro with T. cruzi antigens were concerned, the results showed that CRA, as well as Epi‐Ag, were able to stimulate the production of TNF‐α and IFN‐γ in Chagas patients as compared with NC individuals. However, the cytokine levels after stimulation with the T. cruzi antigens were not different between the patients with CF and IF. CRA was capable of inducing a T helper type 1 (Th1) immune response, with elevated production of TNF‐α and IFN‐γ in Chagas patients that are carriers of CF and IF clinical forms. J. Clin. Lab. Anal. 22:91–98, 2008. © 2008 Wiley‐Liss, Inc.
Does cigarette smoking affect the diagnostic reliability of hemoglobin α2δ2 (HbA2)?
Authors: Tarazi Issa S. , Sirdah Mahmoud M. , El Jeadi Hesham , Al Haddad Rami M. 
Published: March 2008

AbstractQuantitation of hemoglobin α2δ2 (HbA2) is a basic and confirmatory test in diagnosing the carrier state of β‐thalassemia. The present study was designed to investigate the effect of cigarette smoking on the diagnostic reliability of HbA2. A total of 2,867 (654 smokers and 2,213 never smokers) male subjects were involved in the present study. The subjects were categorized into three groups according to their laboratory findings: β‐thalassemia minor, iron deficient, and normal groups. Complete blood count (CBC) parameters and HbA2 levels were compared between smokers and never smokers of each group according to the independent‐samples t‐test using the SPSS® program, significance results were reported at P<0.05. The results showed a significant increase in red blood cell (RBC) mass (RBC count and hematocrit [Hct]) and Hb concentration in smokers of all groups; however, no significant differences were reported in the HbA2 level between smokers and never smokers in all groups. It was concluded that cigarette smoking does not affect the diagnostic reliability of the HbA2 test. J. Clin. Lab. Anal. 22:119–122, 2008. © 2008 Wiley‐Liss, Inc.