bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of non‐linear free surface motions in a cylindrical domain using a Chebyshev–Fourier spectral collocation method
Authors: Chern M. J. , Borthwick A. G. L. , Eatock Taylor R. 
Published: September 2002

AbstractWhen a liquid is perturbed, its free surface may experience highly non‐linear motions in response. This paper presents a numerical model of the three‐dimensional hydrodynamics of an inviscid liquid with a free surface. The mathematical model is based on potential theory in cylindrical co‐ordinates with a σ‐transformation applied between the bed and free surface in the vertical direction. Chebyshev spectral elements discretize space in the vertical and radial directions; Fourier spectral elements are used in the angular direction. Higher derivatives are approximated using a collocation (or pseudo‐spectral) matrix method. The numerical scheme is validated for non‐linear transient sloshing waves in a cylindrical tank containing a circular surface‐piercing cylinder at its centre. Excellent agreement is obtained with Ma and Wu's [Second order transient waves around a vertical cylinder in a tank. Journal of Hydrodynamics 1995; Ser. B4: 72–81] second‐order potential theory. Further evidence for the capability of the scheme to predict complicated three‐dimensional, and highly non‐linear, free surface motions is given by the evolution of an impulse wave in a cylindrical tank and in an open domain. Copyright © 2001 John Wiley & Sons, Ltd.
A level set approach for computing solutions to inviscid compressible flow with moving solid boundary using fixed Cartesian grids
Authors: Chung Meng‐Hsuan 
Published: September 2002

AbstractA level set approach for computing solutions to inviscid compressible flow with moving solid surface is presented. The solid surface is considered to be sharp and is described as the zero level set of a smooth explicit function of space and time. The finite volume TVD–MacCormack's two‐step procedure is used. The boundary conditions on the solid surface are easily implemented by defining the smooth level set function. The present treatment of the level set method allows the handling of fluid flows in the presence of irregularly shaped solid boundaries, escaping from the bookkeeping complexity in the so‐called ‘surface‐tracking’ method. Using the proposed numerical techniques, a two‐dimensional numerical simulation is made to investigate the aerodynamic phenomena induced by two high‐speed trains passing by each other in a tunnel. Copyright © 2001 John Wiley & Sons, Ltd.
The use of LES subgrid‐scale models for shock capturing
Authors: Adams Nikolaus A. 
Published: September 2002

AbstractA method for modelling of flow discontinuities based on deconvolution with a relaxation regularization (DDM) is compared with an essentially non‐oscillatory scheme (ENO) without further modelling and with a dynamic Smagorinsky subgrid‐scale model (DSM). For the DDM approach, a sufficiently accurate representation of the filtered non‐linear combination of discontinuous solution components which arise from the convection term is obtained by regularized deconvolution applied to the filtered solution. For stable integration the evolution equations are supplemented by a relaxation regularization based on a secondary filter operation and a relaxation parameter. We apply the above method to the generic test case of a two‐dimensional solenoidal velocity fluctuation field interacting with a normal shock. The results demonstrate a good agreement of DDM with a reference computation, while DDM significantly reduces computational cost. Predictions with DDM are found to provide a more accurate representation of the shock–vorticity–wave interaction phenomena than that which can be accomplished using the ENO scheme with or without subgrid‐scale model. Copyright © 2002 John Wiley & Sons, Ltd.
VLES modelling of geophysical fluids with nonoscillatory forward‐in‐time schemes
Authors: Smolarkiewicz P. K. , Prusa J. M. 
Published: September 2002

AbstractAtmospheres and oceans are mostly incompressible and turbulent. The experience of the meteorological community with modelling such flows is based primarily on centred in time and space (CTS) methods. Our experience applying non‐oscillatory forward in time methods (NFT) to a range of flows has revealed some unexpected benefits specifically in the area of modelling geophysical turbulence where broad span of scales, density stratification, planetary rotation, inhomogeneity of the lower boundary, etc., make explicit modelling of subgrid‐scale motions particularly challenging. It turns out that in the absence or insufficiency of a proper subgrid‐scale model, NFT methods supply their own, implicit, turbulence models that are quite effective in assuring quality simulations of high‐Reynolds number flows. Since such simulations abandon rigorous notion of the large‐eddy simulation approach, and merely aim at computing explicitly large coherent eddies resolvable on the grid, they are referred to as very‐large‐eddy simulations (VLES). In this paper we will describe advantages of the NFT approach and illustrate them with an example of gravity‐wave‐breaking induced turbulence in a deep atmosphere. On the philosophical side, we challenge a common misconception that NFT methods are overly diffusive and therefore inadequate for high Reynolds number flow simulations. Copyright © 2002 John Wiley & Sons, Ltd.
A rationale for implicit turbulence modelling
Authors: Margolin Len G. , Rider William J. 
Published: September 2002

AbstractWe present a rationale for the success of nonoscillatory finite volume (NFV) difference schemes in modelling turbulent flows without need of subgrid scale models. Our exposition focuses on certain truncation terms that appear in the modified equation of one particular NFV scheme, MPDATA. We demonstrate that these truncation terms have physical justification, representing the modifications to the governing equations that arise when one considers the motion of finite volumes of fluid over finite intervals of time. Published in 2002 by John Wiley & Sons, Ltd.
Defining a common region of deletion at 13q21 in human cancers
Authors: Chen Ceshi , Brabham Will W. , Stultz Brian G. , Frierson Henry F. , Barrett J. Carl , Sawyers Charles L. , Isaacs John T. , Dong Jin‐Tang 
Published: September 2002

AbstractPrevious molecular genetic analyses identified a region of deletion at 13q21 in a variety of human cancers, suggesting the existence of a tumor suppressor gene(s) at this locus. In our earlier study on prostate cancer, the region of deletion was confined to a 3.1 cM interval between D13S152 and D13S162. At present, however, no known gene located in this interval has been firmly implicated in cancer, and the region remains too large for gene identification. To fine‐map the area of interest, we established a contig of bacterial artificial chromosome (BAC) clones, narrowed the region of deletion by loss of heterozygosity (LOH) and homozygosity‐mapping‐of‐deletion (HOMOD) analyses in different types of cancers, and tested a candidate gene from the region for mutation and alteration of expression in prostate cancers. The contig consisted of 75 overlapping BAC clones. In addition to the generation of 47 new sequence‐tagged‐site (STS) markers from the ends of BAC inserts, 76 known STS and expressed sequence tag markers were mapped to the contig (25 kb per marker on average). The minimal region of deletion was further defined to be about 700 kb between markers D13S791 and D13S166 by LOH analysis of 42 cases of prostate cancer, and by HOMOD analysis of eight prostate cancer cell lines/xenografts and 49 cell lines from cancers of the breast, ovary, endometrium, and cervix, using 18 microsatellite markers encompassing the deletion region. A gene that is homologous to the WT1 tumor suppressor gene, AP‐2rep (KLF12), was mapped in this region and was analyzed for its expression and genetic mutation. In addition to low levels of expression in both normal and neoplastic cells of the prostate, this gene did not have any mutations in a group of aggressive prostate cancers and cell lines/xenografts, as assessed by the methods of polymerase chain reaction‐single strand conformational polymorphism analysis and direct sequencing. These studies suggest that a 700 kb interval at 13q21 harbors a tumor suppressor gene(s) that seems to be involved in multiple types of cancer, and that the AP‐2rep gene is unlikely to be an important tumor suppressor gene in prostate cancer. The BAC contig and high‐resolution physical map of the defined region of deletion should facilitate the cloning of a tumor suppressor gene(s) at 13q21. © 2001 Wiley‐Liss, Inc.
Allelic loss on chromosome bands 13q11‐q13 in esophageal squamous cell carcinoma
Authors: Li Guang , Hu Nan , Goldstein Alisa M. , Tang Ze‐Zhong , Roth Mark J. , Wang Quan‐Hong , Dawsey Sanford M. , Han Xiao‐You , Ding Ti , Huang Jing , Giffen Carol , Taylor Philip R. , Emmert‐Buck Michael R. 
Published: September 2002

AbstractAllelic loss on chromosome 13 occurs frequently in esophageal squamous cell carcinoma. However, studies of the two known tumor suppressor genes located on 13q, RB1 and BRCA2, have shown few mutations, suggesting that other genes are likely to be involved in the development of this tumor type. To identify a minimal deletion interval, we first analyzed 42 microsatellite markers spanning chromosome bands 13q11‐q13 in 56 esophageal squamous cell carcinoma patients, including 34 with a family history of upper gastrointestinal cancer and 22 without a family history of cancer. Lifestyle risk factors and clinical/pathologic characteristics were also collected. Two commonly deleted regions were identified: one was located on band 13q12.11, between markers D13S787 and D13S221; the other was located on bands 13q12.3‐q13.1 from markers D13S267 to D13S219. We observed higher allelic loss frequencies for eight of the microsatellite markers in those patients with a family history of upper gastrointestinal cancer compared to patients without such a history. This study suggests that one or more unidentified tumor suppressor genes are located on chromosome arm 13q that play a role in the development of esophageal squamous cell carcinoma. © 2001 Wiley‐Liss, Inc.
An ethnoarchaeological study of chemical residues in the floors and soils of Q'eqchi' Maya houses at Las Pozas, Guatemala
Authors: Fernández Fabián G. , Terry Richard E. , Inomata Takeshi , Eberl Markus 
Published: September 2002

AbstractThis ethnoarchaeological study at the Q'eqchi' Maya village of Las Pozas, Guatemala, aimed to refine the understanding of the relationship between soil chemical signatures and human activities for archaeological applications. The research involved phosphorus, exchangeable ion (calcium, potassium, magnesium, sodium), and trace element analysis of soils and earth floors extracted by Mehlich II, ammonium acetate, and DTPA chelate solutions, respectively. The results showed high levels of phosphorus, potassium, magnesium, and pH in food preparation areas, as well as high phosphorus concentrations and low pH in food consumption areas. The traffic areas exhibited low phosphorus and trace element contents, whereas refuse disposal areas were enriched. These results provide important information for the understanding of space use in ancient settlements. © 2002 Wiley Periodicals, Inc.
Amphotericin B potentiates the activation of inducible nitric oxide synthase and causes nitric oxide‐dependent mitochondrial dysfunction in cytokine‐treated rodent astrocytes
Authors: Trajkovic Vladimir , Markovic Milos , Samardzic Tatjana , Miljkovic Djordje J. , Popadic Dusan , Stojkovic Marija Mostarica 
Published: September 2002

AbstractBecause the neurotoxic effects of the antifungal drug amphotericin B (AMB) closely resemble those ascribed to the highly reactive gaseous free radical nitric oxide (NO), we investigated the effect of AMB on NO production in rodent astrocytes. AMB caused a dose‐dependent increase of NO generation in interferon‐γ (IFN‐γ)‐stimulated rat and mouse astrocytes, as well as in IFN‐γ + tumor necrosis factor‐α (TNF‐α)‐activated rat astrocytoma cell line C6. Treatment of rat astrocytes with AMB markedly potentiated IFN‐γ‐triggered expression of mRNA for iNOS, but not for its transcription factor IRF‐1. The activation of transcription factor NF‐κB was apparently required for AMB‐induced iNOS mRNA expression, as the latter was abolished by NF‐κB inhibitors: pyrrolidine dithiocarbamate and MG132. AMB‐mediated enhancement of astrocyte NO production was partly dependent on endogenous IL‐1, as shown by partial inhibition of AMB effect with IL‐1 receptor antagonist. IFN‐γ + AMB treatment led to reduction of astrocyte mitochondrial respiration (measured by MTT assay) that has been completely reverted by selective iNOS inhibitor aminoguanidine. AMB toxicity toward IFN‐γ‐stimulated astrocytes was dependent on both AMB and NO action, since AMB and NO‐releasing substance SNP synergized in inducing astrocyte mitochondrial dysfunction. These results suggest that the enhancement of cytokine‐induced iNOS activation in astrocytes and the subsequent release of high amounts of NO might be at least partly responsible for AMB neurotoxicity. GLIA 35:180–188, 2001. © 2001 Wiley‐Liss, Inc.
Macrophage depletion impairs oligodendrocyte remyelination following lysolecithin‐induced demyelination
Authors: Kotter Mark R. , Setzu Anna , Sim Fraser J. , Van Rooijen Nico , Franklin Robin J.M. 
Published: September 2002

AbstractAn association between macrophages and remyelination efficiency has been observed in a variety of different models of CNS demyelination. In order to test whether this association is causal or coincidental, we have examined the effects of macrophage depletion on the rate of remyelination of lysolecithin‐induced demyelination in the spinal cord of young adult female rats. Macrophage depletion was achieved by reducing the monocyte contribution to the macrophages within the lesion using the clodronate‐liposome technique. This technique not only resulted in a decrease in Ox‐42–positive cells in the spleen of treated animals but also in the levels of macrophage scavenger receptor type B mRNA expression within the demyelinating lesion. In animals treated with clodronate‐liposomes throughout the remyelination process, there was a significant decrease in the extent of oligodendrocyte remyelination at 3 weeks after lesion induction, but no effect on Schwann cell remyelination. If macrophage depletion was delayed until the second half of the remyelination phase, then there was no effect on the repair outcome, implying that macrophages are required for the early stages of CNS remyelination. The results of this study indicate that the macrophage response is an important component of successful CNS remyelination and that approaches to the treatment of demyelinating disease based on inhibition of the inflammatory response may also impair regenerative events that follow demyelination. GLIA 35:204–212, 2001. © 2001 Wiley‐Liss, Inc.
Continuous interleukin‐6 application in vivo via macroencapsulation of interleukin‐6–expressing COS‐7 cells induces massive gliosis
Authors: Tilgner Johannes , Volk Benedikt , Kaltschmidt Christian 
Published: September 2002

AbstractThe inflammatory cytokine interleukin‐6 (IL‐6) was found in senile plaques of Alzheimer's patients and might be involved in the pathology of Parkinson's disease and multiple sclerosis. Interestingly, an astocytosis is also found in these neurodegenerative disorders. To evaluate the direct effects of IL‐6 in vivo on glial cells, we created a new in vivo model. IL‐6 and mock‐transfected (control group) COS‐7 cells were encapsulated in a poly‐acryl‐nitril membrane for implantation into the rat striatum. Afterward, the host immune reaction to the membrane without encapsulated cells and the biological action of IL‐6–producing capsules was evaluated. Animals with an implanted membrane without cells showed a moderate astrocytosis 5 days after the operation. Furthermore, microglia and T‐cells could be detected and after 30 days the astrocytosis decreased to a small layer around the membrane. In comparison to the control group, which received a sham operation, our results demonstrate that the response of glial cells is caused by the mechanical damage of the surgical procedure itself rather than due to the introduced membrane material. In contrast, we found a massive proliferation and activation of astrocytes and microglia after 10 days by IL‐6–secreting capsules, indicating that IL‐6 is involved in the induction of gliosis. Control animals that received encapsulated mock‐transfected COS‐7 cells showed only a weak response. These data point to an involvement of IL‐6 in the proliferation and activation of glial cells as seen in neurodegenerative disorders. GLIA 35:234–245, 2001. © 2001 Wiley‐Liss, Inc.
Multiple compartments with different metabolic characteristics are involved in biosynthesis of intracellular and released glutamine and citrate in astrocytes
Authors: Waagepetersen Helle S. , Sonnewald Ursula , Larsson Orla M. , Schousboe Arne 
Published: September 2002

AbstractThe metabolism of glucose and lactate was investigated in cultured mouse cerebellar astrocytes, a culture preparation consisting of a homogeneous population of cells, by incubating the cells in a medium containing either [U‐13C]glucose or [U‐13C]lactate in combination with unlabeled lactate and glucose, respectively. After the incubation, cell extracts and media were analyzed by GC/MS (gas chromatography/mass spectrometry) for labeling patterns in aspartate, glutamate, and glutamine, as well as the tricarboxylic acid (TCA) cycle constituents citrate and fumarate. Triple labeling of extracellular citrate exceeded that of double labeling from [U‐13C]glucose. This was not the case when lactate was the labeled precursor. These results indicate that pyruvate carboxylation in biosynthesis of releasable citrate was less prominent from lactate compared with glucose. As observed in the case of extracellular citrate, triple labeling of intracellular aspartate was higher than double labeling when [U‐13C]glucose was the precursor, but not with [U‐13C]lactate as precursor. The pattern of labeling in citrate was different intra‐ and extracellularly and the extent of labeling extracellularly was 10 times higher using [U‐13C]glucose compared with [U‐13C]lactate. However, the intracellular citrate labeling from [U‐13C]glucose only exceeded that originating from labeled lactate by a factor of two. This is in contrast to the labeling pattern obtained for glutamine, since intracellularly this was equally prominent using [U‐13C]glucose and [U‐13C]lactate as substrates. Moreover, extracellularly the labeling was only slightly higher when using [U‐13C]glucose compared with [U‐13C]lactate. Intracellular glutamate and extracellular glutamine exhibited similar incorporation patterns with regard to double compared with triple labeling and the extent of incorporation of label from [U‐13C]lactate compared with [U‐13C]glucose. It should be noted that the main intracellular pools of citrate and glutamine were compartmentalized; i.e., releasable citrate and glutamine exhibited a labeling pattern distinctly different from that of their intracellular pools. Moreover, carboxylation of pyruvate using glucose as the precursor was more important for biosynthesis of releasable glutamine and citrate, compared with their intracellular pools. Based on the results a model of multiple compartments is suggested. The compartments differ with regard to utilization of lactate and glucose, synthetic pathways for TCA cycle intermediates and amino acids, particularly citrate and glutamine, as well as the contents of different metabolites. GLIA 35:246–252, 2001. © 2001 Wiley‐Liss, Inc.
Kinetic study on debromination of vic‐dibromides with trivalent phosphorus compounds
Authors: Yasui Shinro , Itoh Kenji , Ohno Atsuyoshi 
Published: September 2002

AbstractVarious types of trivalent phosphorus compounds (1) brought about reductive debromination of vic‐dibromides (2) to afford olefins. The reaction was accelerated by either electron‐releasing substituents on the phosphorus of 1 or electron‐withdrawing substituents on the α‐carbon of 2. The substituent effects, along with the stereochemistry of the reaction, are consistent with an E1CB‐like mechanism for the elimination of the two bromine atoms. That is, 1 initially undergoes nucleophilic attack upon a bromine of 2. At the transition state, a fractional positive charge is developed on the phosphorus of 1 and a fractional negative charge on the carbon of 2. This mechanism suggests the importance of an electronic character of the vic‐dibromide in determining the relative ease of bromophilicity, carbophilicity, and basicity of the phosphorus of a trivalent phosphorus compound in a reaction with the dibromide. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:217–222, 2001
Interconversion of cyclotrimetallenes and dihalocyclotrimetallanes consisting of group 14 elements
Authors: Ya. Lee Vladimir , Matsuno Tadahiro , Ichinohe Masaaki , Sekiguchi Akira 
Published: September 2002

AbstractThe 1‐ and 2‐disilagermirenes and cyclotrisilene were reacted with carbon tetrachloride or 1,2‐dibromoethane to give almost quantitatively the corresponding dihalocyclotrimetallane derivatives. The crystal structure of 1,2‐dichloro‐1,2,3,3‐tetrakis[di‐tert‐butyl(methyl)silyl]‐1,2‐disilagermirane showed a trans arrangement of the two chlorine atoms in the three‐membered ring system. Reduction of the dihalocyclotrimetallanes with t‐Bu3SiNa quantitatively produced the corresponding starting cyclotrimetallenes. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:223–226, 2001
Appropriate and inappropriate instructional behaviors for international training
Authors: Burba Fengjiao Ji , Petrosko Joseph M. , Boyle Mike A. 
Published: September 2002

AbstractSamples of university students from the United States, Eastern cultures, and Western cultures rated thirty‐one classroom instructional behaviors for appropriateness in their culture. U.S. students had significantly higher appropriateness ratings than Eastern students on clarity of presentation, enthusiasm, classroom interaction, and spatial‐behavioral communication behaviors. Western students exceeded Eastern students in all areas except spatial‐behavioral communication behaviors; ratings of non‐U.S. students were predicted by field of study and age.
The relationship between organizational support, employee development, and organizational commitment: An empirical study
Authors: Tansky Judith W. , Cohen Debra J. 
Published: September 2002

AbstractAn empirical study conducted in a major midwestern hospital found that organizational commitment and perceived organizational support were significantly correlated with satisfaction with career development. Results suggested that when organizations make efforts to develop their managers, the managers become more committed to the organization and also more likely to develop their employees.
Fundamental analysis of boiling heat transfer of magnetic fluids in a magnetic field
Authors: Xu L. , Peng X.F. 
Published: September 2002

AbstractA theoretical investigation was conducted to explore boiling characteristics of magnetic fluids, including the effects of a magnetic field on the surface characteristics of magnetic fluids, the significance of body force and the stress induced. Emphasis was placed on aspects of nucleation, bubble behavior and dynamics. © 2002 Scripta Technica, Heat Trans Asian Res, 31(2): 69–75, 2002; DOI 10.1002/htj.10012