bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimation of systematic error in an equatorial ocean model using data assimilation
Authors: Martin M. J. , Bell M. J. , Nichols N. K. 
Published: October 2002

AbstractAssimilation of temperature observations into an ocean model near the equator often results in a dynamically unbalanced state with unrealistic overturning circulations. The way in which these circulations arise from systematic errors in the model or its forcing is discussed. A scheme is proposed, based on the theory of state augmentation, which uses the departures of the model state from the observations to update slowly evolving bias fields. Results are summarized from an experiment applying this bias correction scheme to an ocean general circulation model. They show that the method produces more balanced analyses and a better fit to the temperature observations. © Crown copyright 2002. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Integral boundary conditions for unsteady biomedical CFD applications
Authors: Nicoud F. , Schönfeld T. 
Published: October 2002

AbstractA methodology to prescribe integral boundary conditions is proposed. The approach makes use of the decomposition of the solution into waves. It applies to any numerical method solving hyperbolic equations, including the compressible Navier–Stokes equations or their incompressible counterpart when solved through an artificial compressibility method. For any physical quantity to be imposed (e.g. the mass flow rate entering the computational domain), the boundary treatment consists in imposing a 1D incoming ‘acoustic’ wave proportional to the difference between the mean quantity of interest (e.g. the mean mass flow rate) over the boundary and its prescribed target value. The approach is validated by computing both steady and pulsated channel flows for Womersley number upto 15. Results from a 3D simulation of the blood flow within a human aortic arch are briefly discussed. Copyright © 2002 John Wiley & Sons, Ltd.
A parallel adaptive projection method for low Mach number flows
Authors: Bell J. B. , Day M. S. , Almgren A. S. , Lijewski M. J. , Rendleman C. A. 
Published: October 2002

AbstractWe describe an adaptive projection method for numerically simulating low Mach number flows. The projection method formulation enforces the velocity divergence constraint resulting from the low Mach number approximation. It is implemented on an adaptive hierarchy of logically rectangular grids, where each finer level is refined in space and in time. The adaptive algorithm has been shown in previous papers to be robust and second‐order accurate, and to satisfy the principles of conservation and free‐stream preservation as applicable. Here, the parallelization is described in some detail, and the methodology is demonstrated on two examples from premixed, low Mach number combustion. Published in 2002 by John Wiley & Sons, Ltd.
Anisotropic adaptation and multigrid for hybrid grids
Authors: Müller Jens‐Dominik 
Published: October 2002

AbstractAn anisotropic refinement method for 2D and 3D hybrid grids is presented and applied to viscous flow problems. The algorithm is unique in that it is not limited to a particular grid structure, e.g. hexahedral elements, but allows the anisotropic division of hexahedra and prisms in 3D, quadrilaterals in 2D and the isotropic division of the other element types. At the core of the method is a novel surface tessellation of an element with hanging nodes which guarantees mesh consistency also in the case of arbitrary directional refinement over an arbitrary number of levels. The efficiency of the anisotropic refinement algorithm is evaluated on viscous flow testcases. The resulting grid sequence is compared to an element‐collapse sequence for its suitability for directionally coarsened multigrid. Copyright © 2002 John Wiley & Sons, Ltd.
Agglomerated multigrid on hybrid unstructured meshes for compressible flow
Authors: Sørensen K. A. , Hassan O. , Morgan K. , Weatherill N. P. 
Published: October 2002

AbstractA review of the applicability of the agglomerated multigrid solution acceleration approach for the simulation of compressible flows is presented. The flow descriptions are wide ranging, spanning from inviscid to turbulent and from steady state to transient. The spatial discretization is performed by a node‐centred finite volume scheme, with explicit addition of fourth‐order artificial dissipation. The improved performance resulting from the introduction of unstructured hybrid meshes is illustrated. For time‐dependent flows involving moving geometries, a second order geometrically conservative scheme is applied, with multigrid accelerated implicit timestepping. Copyright © 2002 John Wiley & Sons, Ltd.
A shape function approach for high‐ and low‐ Reynoldsnear‐wall turbulence models
Authors: Boyer V. , Laurence D. 
Published: October 2002

AbstractA new numerical approach for wall functions is proposed, in order to bridge the gap between low‐ and high‐Reynolds near‐wall turbulence modelling. It allows arbitrary sizes of near‐wall cells with the objective of using local grid refinement or adaptive meshes in industrial calculations. This finite volume‐finite element approach is based on the introduction of assumed shape functions into the energy conservation equations, for the determination of four wall scalings factors. Equilibrium assumptions are avoided, and replaced by formal integration of budget equations in the first cell. The approach is proved accurate and stable in a simple channel flow, but the formalism was developed for non‐equilibrium situations where it still needs to be tested. Copyright © 2002 John Wiley & Sons, Ltd.
Aerospace simulations on parallel computers using unstructured grids
Authors: Weatherill N. P. , Hassan O. , Morgan K. , Jones J. W. , Larwood B. G. , Sorenson K. 
Published: October 2002

AbstractIf complex simulations on realistic configurations are to be performed, it is critical that the large volume of data that will be produced can be handled efficiently. In our work, we have chosen to parallelize all the steps in the computational cycle; unstructured mesh generation, solvers, adaptation and visualization. In this way, data is distributed at the early stage of mesh generation and is never brought together, thereby preventing data bottlenecks. Using these parallel modules, large‐scale simulations have been performed for both computational fluid dynamics and computational electromagnetics. The paper briefly describes the approaches taken to parallelizing the unstructured grid techniques and examples are given using meshes to a quarter of a billion elements. Copyright © 2002 John Wiley & Sons, Ltd.
Nonlinear dynamics in high‐frequency intraday financial data: Evidence for the UK long gilt futures market
Authors: McMillan David G. , Speight Alan E. H. 
Published: October 2002

AbstractRecent research investigating the properties of high‐frequency financial data has suggested that the
stochastic nonlinearity widely present in such data may be characterized by heterogeneous components in
conditional volatility, and nonlinear dependence of threshold autoregressive form due to market frictions. This
article tests for the presence of such effects in intraday long gilt futures returns on the UK LIFFE market.
Tests against the null of linearity indicate the significance of smooth transition autoregressive nonlinearities
in such returns at the 5‐min frequency, which entails a first‐order autoregressive process with
switching intercept. This nonlinear structure is robust to the presence of asymmetric and component structures
in conditional variance, and consistent with the existence of heterogeneous traders facing different levels of
transaction costs, noise trader risk, or capital constraints. © 2002 Wiley Periodicals, Inc. Jrl Fut Mark
22:1037–1057, 2002
Cryptic translocation t(5;11)(q35;p15.5) with involvement of the NSD1 and NUP98 genes without 5q deletion in childhood acute myeloid leukemia
Authors: Panarello Claudio , Rosanda Cristina , Morerio Cristina 
Published: October 2002

AbstractThe cryptic translocation t(5;11)(q35;p15.5), which creates a NSD1‐NUP98 fusion gene, has been associated with a deletion of the long arm of chromosome 5, del(5q), in pediatric acute myeloid leukemia (AML) patients with differentiated phenotype. We screened five pediatric cases of AML with apparently normal karyotype by use of fluorescence in situ hybridization analysis and detected one case with early myeloid phenotype and poor clinical outcome, but with the same breakpoints and no del(5q). These findings point to the involvement of t(5;11) as an early event in leukemogenesis. Screening for this translocation in AML patients with apparently normal karyotype at onset is recommended. © 2002 Wiley‐Liss, Inc.
Poly(ADP‐ribose) polymerase inhibitor increases growth inhibition and reduces G2/M cell accumulation induced by temozolomide in malignant glioma cells
Authors: Tentori Lucio , Portarena Ilaria , Torino Francesco , Scerrati Massimo , Navarra Pierluigi , Graziani Grazia 
Published: October 2002

AbstractTemozolomide (TZM) is a novel methylating agent currently under investigation for treatment of recurrent high‐grade gliomas. Although TZM generates a wide spectrum of methyl adducts, its cytotoxicity has been attributed to mismatch repair (MR)‐mediated processing of O6‐methylguanine:T mispairs. N3‐methyladenine and N7‐methylguanine adducts are promptly repaired by the base excision repair system, unless a poly(ADP‐ribose) polymerase (PARP) inhibitor is combined to TZM. In this case, the repair process of N‐methylpurines cannot be completed and the deriving DNA strand breaks contribute to cytotoxicity. In this study, we investigated the influence on cell growth and cell cycle of treatment with TZM + PARP inhibitor in glioma cells characterized by different susceptibility to TZM. The results indicated that PARP inhibitor increases growth inhibition induced by TZM in either p53–wild‐type or p53‐mutant glioblastoma cells, as early as 24 h after drug exposure. The enhancing effect exerted by PARP inhibitor was particularly evident in glioma cells characterized by a defective expression of MR, since these cells are tolerant to O6‐methylguanine damage and show low sensitivity to TZM. In O6‐alkylguanine‐DNA alkyltransferase (OGAT)‐deficient and MR‐proficient tumor cells bearing wild‐type p53, the drug combination markedly reduced cell accumulation in the G2/M phase of cell cycle and induction of the G2 checkpoint regulator Chk1 kinase. In short‐term cultures of glioma cells derived from surgical specimens, PARP inhibitor enhanced chemosensitivity to TZM and this effect was especially evident in OGAT‐proficient tumors. Thus, a pharmacological strategy based on the interruption of N‐methylpurine repair might represent a novel strategy to restore or increase glioma sensitivity to TZM. GLIA 40:44–54, 2002. © 2002 Wiley‐Liss, Inc.
Chloride/anion channels in glial cell membranes
Authors: Walz Wolfgang 
Published: October 2002

AbstractAt least seven different chloride/anion currents have now been identified in astrocytes, oligodendrocytes/Schwann cells, and microglia. Only for two of these currents is the corresponding gene known. One of these genes is not encoding for a chloride channel, but for a class of mitochondria‐like pores also found in cell membranes. Astrocytes and oligodendrocytes differ in their resting properties: astrocytes accumulate chloride but do not have a significant permeability. Oligodendrocytes have a close to passive distribution and a significant permeability. Under certain circumstances, astrocytes can express a resting chloride conductance. Reactive and neoplastic astrocytes as well as astrocytes with an altered shape exhibit a resting conductance. The function of these channels certainly involves volume regulation. Other possible functions are potassium homeostasis, migration, proliferation (in microglia), and involvement in spreading depression waves. Of greatest interest are two phenomena discovered in situ: The ClC‐2 channel is only found in astrocytic endfeet near blood capillaries adjacent to neuronal GABAA receptors. In the supraoptic nucleus of the hypothalamus, there is an osmosensitive astrocytic taurine release. This released taurine interacts with glycine receptors in neighboring neurons, causing inhibition. It is assumed that with the future availability of more in situ, rather than in vitro, studies, an increased number of such complex interactions between glial cells, neurons, and blood vessels will be discovered. GLIA 40:1–10, 2002. © 2002 Wiley‐Liss, Inc.
Depression and anxiety in memory clinic attenders and their carers: implications for evaluating the effectiveness of cognitive rehabilitation interventions
Authors: Clare Linda , Wilson Barbara A. , Carter Gina , Breen Kristin , Berrios German E. , Hodges John R. 
Published: October 2002

AbstractBackgroundThe potential of cognitive rehabilitation (CR) for people who have a diagnosis of Alzheimer's disease (AD) is increasingly being recognised. It has been suggested, however, that interventions targeting memory functioning in AD have negative effects on the well‐being of participants and carers in terms of mood and perceived strain. While some ‘memory training’ studies do report an increase in self‐report scores on scales assessing these variables, it is not clear whether the changes are attributable to the intervention. There is some overlap between CR and ‘memory training’, but CR is a much more individualised approach, and therefore CR intervention studies often adopt within‐subjects or single case experimental designs, for which relevant comparison data are required.MethodParticipant and carer depression and anxiety, and carer strain, were assessed at initial attendance and again by postal survey 6 months later in a consecutive series of 94 Memory Clinic referrals who received standard treatment but no specialised CR interventions.ResultsAt the group level, there were no statistically significant changes in scores at follow up, athough the participants scoring above designated cut‐points were not necessarily the same individuals at the two time points.ConclusionsThe study provided useful comparison data for use in evaluating the effects of cognitive rehabilitation interventions on mood and carer strain, showing that in the absence of intervention scores remain generally stable over time. Significant changes observed in intervention studies should be viewed in this context. Copyright © 2002 John Wiley & Sons, Ltd.
Assessment of shallow landsliding by using a physically based model of hillslope stability
Authors: Borga Marco , Dalla Fontana Giancarlo , Gregoretti Carlo , Marchi Lorenzo 
Published: October 2002

AbstractA model for the simulation of shallow landsliding triggered by heavy rainstorms is analysed and discussed. The model is applied in two mountainous catchments in the Dolomites (Eastern Italian Alps): the Cordon catchment (5 km2) and the Vauz catchment (1·9 km2), where field surveys provided a description of hydraulic and geotechnical properties of soils and an inventory of landslide scars is available. The stability mapping procedure, which is similar to that proposed by Montgomery and Dietrich (1994 Water Resources Research 30: 1153), combines steady‐state hydrologic concepts with the infinite slope stability model. The model provides an estimate of the spatial distribution of the critical rainfall, which is the minimum steady‐state rainfall predicted to cause instability. The comparison of the landslides observed in the study basins with model predictions shows that the distribution of critical rainfall obtained from the model provides a surrogate for failure initiation probability as a function of topographic location. Copyright © 2002 John Wiley & Sons, Ltd.
Antiproliferative, antiangiogenic and proapoptotic activity of h‐R3: A humanized anti‐EGFR antibody
Authors: Crombet‐Ramos Tania , Rak Janusz , Pérez Rolando , Viloria‐Petit Alicia 
Published: October 2002

AbstractThe epidermal growth factor receptor (EGFR) proto‐oncogene is frequently overexpressed in tumors of epithelial origin. This event is thought to be causative for tumor development and progression and henceforth associated with poor prognosis. The recent considerable interest in developing EGFR‐targeting agents resulted in derivation of the monoclonal, humanized, neutralizing antibody h‐R3, which binds to the extracellular domain of EGFR with high affinity and strongly inhibits EGFR‐dependent cellular transformation. Thus, treatment of A431 squamous cell carcinoma cells with h‐R3 in either 2‐dimensional or 3‐dimensional culture resulted in appreciable antimitotic effects through induction of the G1 arrest. Although h‐R3 does not appear to have a direct proapoptotic activity in this setting, it inhibits production of the vascular endothelial growth factor (VEGF) by A431 cells both in vitro and in vivo. In the latter case, h‐R3 treatment (0.25–1 mg/mouse; every other day per 2 weeks) not only significantly reduced VEGF mRNA expression of A431 tumors growing subcutaneously in SCID mice but also resulted in reduction of the overall microvascular density (MVD), disappearance of dilated “mother vessels,” as well as in suppression of tumor growth followed by regression of established tumors. This apparent antiangiogenic activity of h‐R3 was associated with reduction in Ki67‐positive tumor cell fraction and (unlike in vitro) also with an elevated apoptotic index, the latter indicative of a cytotoxic mode of action in vivo. Taken together, h‐R3 is a promising new antagonist of the EGFR oncogene, the anticancer properties of which are associated with combined and potent antiproliferative, antiangiogenic and proapoptotic activity. © 2002 Wiley‐Liss, Inc.
Intervening with foster infants' caregivers: Targeting three critical needs
Authors: Dozier Mary , Higley Elizabeth , Albus Kathleen E. , Nutter Anna 
Published: October 2002

AbstractThis article presents the theoretical and empirical rationale for an intervention that targets three critical needs of infants and young children in foster care. First, foster children tend to give behavioral signals that lead even nurturing caregivers to provide non‐nurturing care. Foster parents, therefore, need services that help them to reinterpret children's behavioral signals. Second, some caregivers are not comfortable providing nurturance. When surrogate caregivers do not provide nurturance to foster children, their children are at risk for a range of problematic outcomes. The second intervention component, therefore, targets caregiver difficulties in providing nurturance. Third, foster children are at risk for behavioral and biobehavioral dysregulation as the result of disrupted relationships with previous caregivers. The final intervention component helps caregivers provide children with a predictable interpersonal environment such that children develop better regulatory capabilities. ©2002 Michigan Association for Infant Mental Health.
The effects of diabetes with hyperlipidemia on P450 expression in APA hamster livers
Authors: Takatori Atsushi , Akahori Mizuki , Kawamura Seiji , Itagaki Shin‐ichi , Yoshikawa Yasuhiro 
Published: October 2002

AbstractThe effect of chronic hyperglycemia and hyperlipidemia induced by streptozotocin (SZ) on the expression of P450 in the liver of APA hamsters was studied in this experiment. No effect on the total activity of P450 was seen in SZ‐induced diabetic hamsters throughout the experimental period. At 1 and 6 months after SZ‐injection, the levels of CYP1A, 2C6, and 3A of SZ‐injected hamsters were much lower than those of age‐matched control hamsters. CYP2B expression tended to decrease and CYP2E1 and 4A expression tended to increase in SZ‐injected hamsters, although the results were not significant. At 3 months after SZ‐injection, however, no significant difference between SZ‐injected and normal hamsters was seen in these P450 isozymes. On the other hand, CYP2C11 expression was slightly depressed in SZ1M and SZ6M, and almost equivalent to control hamsters in SZ3M. Immunohistochemistry by the use of each isozyme antibody revealed that SZ‐induced diabetes affected the localization of CYP2C6, 3A, and 4A in the hepatic acinus. The expression of CYP2C6 and 3A was depressed mainly in the periportal region of the acinus, and CYP4A expression was induced mainly in the perivenous region by SZ‐induced diabetes. On the other hand, the expression pattern of CYP1A, 2B, 2C11, and 2E1 were not affected. These results demonstrate that the effects of SZ‐induced diabetes on hepatic P450 differ for each isozyme in APA hamsters and also differ from those of other experimental diabetic animals, including golden hamsters. © 2002 Wiley Periodicals, Inc. J Biochem Mol Toxicol 16:174–181, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10036
Discovery of Sonic hedgehog expression in postnatal growth plate chondrocytes: Differential regulation of Sonic and Indian hedgehog by retinoic acid
Authors: Wu Licia N.Y. , Lu Min , Genge Brian R. , Guo George Y. , Nie Daotai , Wuthier Roy E. 
Published: October 2002

AbstractSonic hedgehog (Shh) is a key signal protein in early embryological patterning of limb bud development. Its analog, Indian hedgehog (Ihh), primarily expressed during early cartilage development in prehypertrophic chondrocytes, regulates proliferation and suppresses terminal differentiation of postnatal growth plate (GP) chondrocytes. We report here for the first time that both Shh and Ihh mRNA are expressed in the GP of rapidly growing 6‐week‐old broiler‐strain chickens. They are also expressed in other tissues such as articular chondrocytes, kidney, and bone. In situ hybridization and RT‐PCR analyses reveal Shh in all zones of the GP, with peak expression in late hypertrophy. Using primary cultures of GP chondrocytes in serum‐containing medium, we followed the patterns of Shh and Ihh mRNA expression as the cultures matured and mineralized. We find a cyclical expression of both hedgehog genes during the early period of culture development between day 10 and 14; when one is elevated, the other tended to be suppressed, suggesting that the two hedgehogs may play complementary roles during GP development. Retinoic acid (RA), a powerful modulator of gene expression in cell differentiation, stimulates GP chondrocytes toward terminal differentiation, enhancing mineral formation. We find that RA strongly suppresses Ihh, but enhances expression of Shh in this system. While Ihh suppresses maturation of GP chondrocytes to hypertrophy, we hypothesize that Shh acts to push these cells toward hypertrophy. J. Cell. Biochem. 87: 173–187, 2002. © 2002 Wiley‐Liss, Inc.
Water polarizability in condensed phase: Ab initio evaluation by cluster approach
Authors: Morita Akihiro 
Published: October 2002

AbstractThe polarizability of a water molecule in liquid is evaluated via ab initio and density functional calculations for water clusters. This work has considerably improved our previous effort [J Chem Phys 1999, 110, 11987] to attain quantitative accuracy for polarizability. The calculations revealed that the water polarizability in the liquid is reduced from that in the gaseous phase by 7–9%. These results suggest significant implications for polarizable water models. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 1466–1471, 2002