bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progenitors in the postnatal cerebellar white matter are antigenically heterogeneous
Authors: Milosevic Ana , Goldman James E. 
Published: October 2002

AbstractProgenitors that migrate through the white matter of the postnatal cerebellum give rise to cortical interneurons, astroglia, and oligodendroglia. To determine whether this progenitor population is heterogeneous with respect to specific lineage markers, we infected progenitors in vivo with a retrovirus encoding the green fluorescent protein on postnatal day 4/5 and labeled them in situ with various antibodies 2 days postviral injection: the neuronal marker was the transcription factor SOX1; early oligodendroglial markers were chondroitin sulfate proteoglycan antigen and platelet‐derived growth factor receptor‐α. Markers for astroglial progenitors were vimentin, nestin, zebrin II, and the astroglial‐specific glutamate transporter subtype GLAST. None of the progenitors was doubly labeled with any combination of markers characteristic for different cell lineages. Most progenitors were not labeled with any of the various combinations of antibodies used. Progenitors did not express markers characteristic for mature astroglia (GFAP), oligodendroglia (CNPase), or neurons (MAP2). Thus, although these progenitors are morphologically indistinguishable, a minority expresses markers of early neuronal or glial lineages, suggesting that they begin to differentiate during migration. J. Comp. Neurol. 452:192–203, 2002. © 2002 Wiley‐Liss, Inc.
GABAergic circuitry in the dorsal division of the cat medial geniculate nucleus
Authors: Coomes Diana L. , Bickford Martha E. , Schofield Brett R. 
Published: October 2002

Abstractγ‐Aminobutyric acid (GABA) is the main inhibitory neurotransmitter of the thalamus. We used postembedding immunocytochemistry to examine the synaptic organization of GABA‐positive profiles in the dorsal superficial subdivision of the cat medial geniculate nucleus (MGN). Three groups of GABA‐positive profiles participate in synapses: axon terminals, dendrites, and presynaptic dendrites. The presynaptic GABA‐positive terminals target mainly GABA‐negative dendrites. The GABA‐positive postsynaptic profiles receive input primarily from GABA‐negative axons. The results indicate that the synaptic organization of GABA‐positive profiles in the dorsal superficial subdivision of the MGN nucleus is very similar to that in other thalamic nuclei. J. Comp. Neurol. 453:45–56, 2002. © 2002 Wiley‐Liss, Inc.
PSA‐NCAM immunocytochemistry in the cerebral cortex and other telencephalic areas of the lizard Podarcis hispanica: Differential expression during medial cortex neuronal regeneration
Authors: Ramirez‐Castillejo Carmen , Nacher Juan , Molowny Asuncion , Ponsoda Xavier , Lopez‐Garcia Carlos 
Published: October 2002

AbstractThe lizard medial cortex, a region homologous to the mammalian dentate gyrus, shows postnatal neurogenesis and the surprising ability to replace its neurons after being lesioned specifically with the neurotoxin 3‐acetylpyridine. As the polysialylated form of the neural cell adhesion molecule (PSA‐NCAM) is expressed during neuronal migration and differentiation, we have studied its distribution in adult lizards and also during the lesion‐regeneration process. In the medial cortex of control animals, many labeled fusiform somata, presumably corresponding to migratory neuroblasts, appeared in the inner plexiform layer. There were also scattered immunoreactive granule neurons in the cell layer. Double immunocytochemistry with 5′‐bromodeoxyuridine revealed that some of the PSA‐NCAM–expressing cells in the inner plexiform and cell layers were generated recently. PSA‐NCAM immunoreactivity was also present in the dorsomedial, dorsal, and lateral cortices, as well as in the dorsal ventricular ridge, the nucleus accumbens, and the nucleus sphericus. Twelve hours after the injection of 3‐acetylpyridine, some medial cortex granule neurons appeared degenerated, although some of them still expressed PSA‐NCAM. One to 2 days after the injection, most granule neurons appeared degenerated and no PSA‐NCAM immunoreactivity was detected in the medial cortex cell layer. Four to 7 days after treatment, abundant labeled fusiform cells populated the inner plexiform layer and some immunoreactive somata were seen in the cell layer. Fifteen to 30 days after the neurotoxin injection, the number of PSA‐NCAM expressing granule neurons augmented considerably and the level was still above control levels in lizards that survived 42 days. Our results show for the first time the expression of PSA‐NCAM in a reptile brain, where it appears to participate in the migration and differentiation of granule neurons during adult neurogenesis and regeneration. J. Comp. Neurol. 453:145–156, 2002. © 2002 Wiley‐Liss, Inc.
A quality‐of‐service‐based framework for creating distributed heterogeneous software components
Authors: Raje Rajeev R. , Bryant Barrett R. , Olson Andrew M. , Auguston Mikhail , Burt Carol 
Published: October 2002

AbstractComponent‐based software development offers a promising solution for taming the complexity found in today's distributed applications. Today's and future distributed software systems will certainly require combining heterogeneous software components that are geographically dispersed. For the successful deployment of such a software system, it is necessary that its realization, based on assembling heterogeneous components, not only meets the functional requirements, but also satisfies the non‐functional criteria such as the desired quality of service (QoS). In this paper, a framework based on the notions of a meta‐component model, a generative domain model and QoS parameters is described. A formal specification based on two‐level grammar is used to represent these notions in a tightly integrated way so that QoS becomes a part of the generative domain model. A simple case study is described in the context of this framework. Copyright © 2002 John Wiley & Sons, Ltd.
Interpretation of atypical patterns encountered when using a flow cytometry–based method to detect residual leukocytes in leukoreduced red blood cell components
Authors: Janatpour K. , Paglieroni T. G. , Schuller L. , Foley K. , Rizzardo T. , Holland P. V. 
Published: October 2002

AbstractBackgroundUniversal leukoreduction of blood components is becoming the standard of care. Flow cytometry methods are being used for quality control of the leukoreduction process.MethodsWe provide an atlas of atypical flow cytograms generated by a commercial LeucoCOUNT™ assay that was used to enumerate residual leukocytes in leukoreduced red blood cell components. Numeric results are derived from a flow cytogram generated by the assay.ResultsThree types of atypical flow cytogram patterns were observed during process validation or routine quality control of leukoreduced red blood cell components. (a) Fixation artifact: Fixation of control or test samples can alter the staining intensity compared with fresh cells. (b) “Rain” pattern: Flow cytometry methods count slightly damaged leukocytes not removed during leukoreduction. Slightly damaged leukocytes appear on a flow cytogram like “rain” falling from a well‐defined “cloud” of intact residual leukocytes. Discrepancies between automated flow cytometry results and subjective manual counting methods can occur. (c) Autofluorescence‐debris pattern: Cell debris and age‐related changes in the sample can cause shifts in the fluorescence staining pattern, resulting in erroneous test results.ConclusionReview of flow cytograms is essential for accurate reporting of flow cytometry–based methods for enumerating residual leukocytes in leukoreduced blood components. Cytometry (Clin. Cytometry) 50:254–260, 2002. © 2002 Wiley‐Liss, Inc.
A PWM rectifier/inverter system capable of suppressing both harmonics and EMI
Authors: Ogasawara Satoshi , Fujikawa Masato , Akagi Hirofumi 
Published: October 2002

AbstractThis paper proposes a new PWM rectifier/inverter system that is capable of suppressing not only supply harmonic currents but also electromagnetic interference (EMI). The conversion system consists of a PWM rectifier and inverter, and an active common‐noise canceler (ACC) which has been proposed by the authors. The ACC developed for this system is characterized by the sophisticated connection of a common mode transformer which can compensate for common mode voltages produced by both the PWM rectifier and inverter. As a result, the size of the common mode transformer can be reduced to one‐third, compared with the previously proposed ACC. A prototype PWM rectifier/inverter system (2.2 kW) has been implemented and tested. Some experimental results show reduction characteristics of the supply harmonic current and EMI. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(4): 59–68, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10062
Screening the Hanford tanks for trapped gas
Authors: Whitney Paul , Chen Guang 
Published: October 2002

AbstractThe Hanford Site is home to 177 large, underground nuclear waste storage tanks. This article describes a screening study carried out in the mid 1990s that used the tank waste level measurements to assess the tanks for potential flammable gas hazards. At the time of the study, 25 of the 177 tanks were on the flammable gas watch list. The use of this monitoring data provided additional insight, resulting in operational changes on the Hanford site.The waste level measurements used in this study were made primarily to monitor the tanks for leaks and intrusions. Four measurement devices are widely used in these tanks. Three of these measure the level of the waste surface. The remaining device measures from within a well embedded in the waste, thereby monitoring the liquid level even if the liquid level is below a dry waste crust. The data from each of the four measurement devices were utilized in this investigation.The analytic method used for this screening was to look for an inverse correlation between waste level measurements and ambient atmospheric pressure. If the waste level in a tank decreases with an increase in ambient atmospheric pressure, then the compressibility may be attributed to gas trapped within the waste. In this article, this methodology is not used to estimate the volume of gas trapped in the waste. Copyright © 2002 John Wiley & Sons, Ltd.
Rank kriging for characterization of mercury contamination at the East Fork Poplar Creek, Oak Ridge, Tennessee
Authors: Singh Ashok K. , Ananda M. M. A. 
Published: October 2002

AbstractThe spatial interpolation method of kriging, originally developed for estimation of ore reserves in mining and prediction in meteorology, is an important geostatistical tool for characterization of a Superfund site. Point kriging uses an estimated variogram to compute the best linear unbiased estimates (BLUE) of contaminant concentration at an unsampled location. When the contaminant concentration data is heavily skewed, the data are typically log‐transformed and kriging is performed on the transformed data. The results obtained from kriging the log‐transformed data are then back‐transformed. This back‐transformation formula involves not only the estimated log‐transformed values but also their kriging standard deviations (ksd). This method of kriging, referred to in the geostatistical literature as log‐normal kriging, was initially used to characterize the East Fork Poplar Creek (EFPC) Superfund site in Oak Ridge, Tennessee. The back‐transformed values for the EFPC site produced estimates of mercury contamination that were orders of magnitude higher than the maximum observed mercury concentration at the site. The method of rank variogram modeling/rank kriging was developed by the authors to estimate mercury contamination at the EFPC site. We present the method of rank variogram modeling/rank kriging, illustrate it with an example, and briefly describe the kriging results obtained for the EFPC site.The log‐normal probability model is routinely applied in statistical analysis of contaminant concentration data as well. The upper confidence limit (UCL) for log‐normally distributed data is typically calculated by using the H‐statistics based formula. The UCL of the mean at times turns out to be orders of magnitude higher than the maximum observed contaminant concentration. An example is presented to illustrate this unreasonable behavior of the H‐UCL formula. Copyright © 2002 John Wiley & Sons, Ltd.
Contending with space–time interaction in the spatial prediction of pollution: Vancouver's hourly ambient PM10 field
Authors: Zidek Jim , Sun Li , Le Nhu , Özkaynak Halûk 
Published: October 2002

AbstractIn this article we describe an approach for predicting average hourly concentrations of ambient PM10 in Vancouver. We know our solution also applies to hourly ozone fields and believe it may be quite generally applicable. We use a hierarchical Bayesian approach. At the primary level we model the logarithmic field as a trend model plus Gaussian stochastic residual. That trend model depends on hourly meteorological predictors and is common to all sites. The stochastic component consists of a 24‐hour vector response that we model as a multivariate AR(3) temporal process with common spatial parameters. Removing the trend and AR structure leaves ‘whitened’ time series of vector series. With this approach (as opposed to using 24 separate univariate time series models), there is little loss of spatial correlation in these residuals compared with that in just the detrended residuals (prior to removing the AR component). Moreover our multivariate approach enables predictions for any given hour to ‘borrow strength’ through its correlation with adjoining hours. On this basis we develop a spatial predictive distribution for these residuals at unmonitored sites. By transforming the predicted residuals back to the original data scales we can impute Vancouver's hourly PM10 field. Copyright © 2002 John Wiley & Sons, Ltd.
Using spatial models and kriging techniques to optimize long‐term ground‐water monitoring networks: a case study
Authors: Cameron Kirk , Hunter Philip 
Published: October 2002

AbstractIn a pilot project, a spatial and temporal algorithm (geostatistical temporal–spatial or GTS) was developed for optimizing long‐term monitoring (LTM) networks. Data from two monitored ground‐water plumes were used to test the algorithm. The primary objective was to determine the degree to which sampling, laboratory analysis, and/or well construction resources could be pared without losing key statistical information concerning the plumes. Optimization of an LTM network requires an accurate assessment of both ground‐water quality over time and trends or other changes in individual monitoring wells. Changes in interpolated concentration maps over time indicate whether ground‐water quality has improved or declined. GTS separately identifies temporal and spatial redundancies. Temporal redundancy may be reduced by lengthening the time between sample collection. Spatial redundancy may be reduced by removing wells from the network which do not significantly impact assessment of ground‐water quality.Part of the temporal algorithm in GTS involves computation of a composite temporal variogram to determine the least redundant overall sampling interval. Under this measure of autocorrelation between sampling events, the lag time at which the variogram reaches a sill is the sampling interval at which same‐well measurements lack correlation and are therefore non‐redundant. The spatial algorithm assumes that well locations are redundant if nearby wells offer nearly the same statistical information about the underlying plume. A well was considered redundant if its removal did not significantly change: (i) an interpolated map of the plume; (ii) the local kriging variances in that section of the plume; and (iii) the average global kriging variance. To identify well redundancy, local kriging weights were accumulated into global weights and used to gauge each well's relative contribution to the interpolated plume map. By temporarily removing that subset of wells with the lowest global kriging weights and re‐mapping the plume, it was possible to determine how many wells could be removed without losing critical information.Test results from the Massachusetts Military Reserve (MMR) indicated that substantial savings in sampling, analysis and operational costs could be realized by utilizing GTS. Annual budgetary savings that would accrue were estimated at between 35 per cent and 5 per cent for both LTM networks under study.Copyright © 2002 John Wiley & Sons, Ltd.
Discrete filtering of numerical solutions to hyperbolic conservation laws
Authors: Bürgel A. , Sonar T. 
Published: October 2002

AbstractIn the framework of finite volume approximations to the Euler equations of gas dynamics we introduce computationally cheap difference schemes in addition with efficient discrete filter operators correcting discrete values locally. After presentation of a classical discrete filter algorithm we describe for the first time the implementation of a TV filter, originally developed in signal and image processing, in the context of hyperbolic conservation laws on unstructured grids. Copyright © 2002 John Wiley & Sons, Ltd.
Anisotropic adaptivity for the finite element solutions of three‐dimensional convection‐dominated problems
Authors: Walkley Mark , Jimack Peter K. , Berzins Martin 
Published: October 2002

AbstractConvection‐dominated problems are typified by the presence of strongly directional features such as shock waves or boundary layers. Resolution of numerical solutions using an isotropic mesh can lead to unnecessary refinement in directions parallel to such features. This is particularly important in three dimensions where the grid size increases rapidly during conventional isotropic refinement procedures. In this work, we investigate the use of adaptive finite element methods using anisotropic mesh refinement strategies for convection‐dominated problems. The strategies considered here aim to resolve directional features without excessive resolution in other directions, and hence achieve accurate solutions more efficiently. Two such strategies are described here: the first based on minimization of the least‐squares residual; the second based on minimizing a finite element error estimate. These are incorporated into an hr‐adaptive finite element method and tested on a simple model problem. Copyright © 2002 John Wiley & Sons, Ltd.
Block preconditioners for the discrete incompressible Navier–Stokes equations
Authors: Elman Howard C. , Silvester David J. , Wathen Andrew J. 
Published: October 2002

AbstractWe examine the convergence characteristics of iterative methods based on a new preconditioning operator for solving the linear systems arising from discretization and linearization of the steady‐state Navier–Stokes equations. For steady‐state problems, we show that the preconditioned problem has an eigenvalue distribution consisting of a tightly clustered set together with a small number of outliers. These characteristics are directly correlated with the convergence properties of iterative solvers, with convergence rates independent of mesh size and only mildly dependent on viscosity. For evolutionary problems, we show that implicit treatment of the time derivatives leads to systems for which convergence is essentially independent of viscosity. Copyright © 2002 John Wiley & Sons, Ltd.
A conservative pressure‐correction method for the Euler and ideal MHD equations at all speeds
Authors: van der Heul D. R. , Vuik C. , Wesseling P. 
Published: October 2002

AbstractTo efficiently compute weakly compressible magnetohydrodynamic flows in astrophysical applications, approximate low Mach number reduced forms of the compressible MHD equations are frequently used. This is because standard characteristic‐based schemes for the full compressible MHD equations are inefficient and inaccurate for computing low Mach number magnetohydrodynamic flow, as a result of the increasing stiffness and weakening pressure/density coupling of the equations when M ↓ 0. Furthermore, these schemes are colocated, so that additional and artificial measures have to be taken to ensure solenoidality of the magnetic field. We present a new method with a staggered spatial discretization and a pressure‐correction solution algorithm that is more suitable for computing weakly compressible MHD flow, because of its Mach‐uniformity and efficient and accurate handling of the solenoidality constraint on the magnetic field. Copyright © 2002 John Wiley & Sons, Ltd.
Subcellular localization of the BRCA1 gene product in mitotic cells
Authors: Lotti Lavinia Vittoria , Ottini Laura , D'Amico Cristina , Gradini Roberto , Cama Alessandro , Belleudi Francesca , Frati Luigi , Torrisi Maria Rosaria , Mariani‐Costantini Renato 
Published: October 2002

AbstractThe product of the hereditary breast cancer susceptibility gene BRCA1 is a multifunctional protein involved in the maintenance of genomic integrity, in transcriptional coactivation, and in the control of cell growth. BRCA1‐deficient cells manifest chromosomal instability. During mitosis, BRCA1 is known to interact with γ‐tubulin in the centrosomes, key elements of the mitotic spindle. Using confocal microscopy and immunogold electron microscopy, we investigated the distribution of endogenous BRCA1 relative to mitotic spindle markers in breast cancer cells. By confocal analysis, BRCA1 and β‐tubulin colocalized to microtubules of the mitotic spindle and to the centrosomes. Immunogold electron microscopy confirmed these results and further revealed that BRCA1 and α‐tubulin codistributed to the walls of the centrioles and to pericentriolar fibers at centrosomes. During chromatid segregation, codistribution was also detected along individual spindle microtubules and at sites of insertion of microtubules on chromosomes. At cytokinesis, BRCA1 and α‐tubulin codistributed to the midbody. Coimmunoprecipitation supported the association of full‐length BRCA1 with α‐ and β‐tubulin. These results are consistent with an involvement of BRCA1 in the dynamics of the mitotic spindle and in the segregation of duplicated chromosomes. © 2002 Wiley‐Liss, Inc.
Effects of emotion‐oriented care on elderly people with cognitive impairment and behavioral problems
Authors: Schrijnemaekers Veron , van Rossum Erik , Candel Math , Frederiks Carla , Derix Mayke , Sielhorst Hilde , van den Brandt Piet 
Published: October 2002

AbstractObjectiveThis study investigates the effects of emotion‐oriented care on the behavior of elderly people with cognitive impairment and behavioral problems. This approach is mainly based on the validation approach, but also uses insights from other approaches like reminiscence and sensory stimulation.Methods16 Homes for the aged with structured day care units were randomly allocated to an intervention or control group. 151 Residents with cognitive impairment and behavioral problems were included in the study. The eight intervention homes received a training program with regard to emotion‐oriented care. In the eight control homes usual care was continued. Measurements were performed at baseline and after 3, 6 and 12 months of follow‐up (assessment by caregivers and relatives). The primary outcome measure was the change in behavior of the residents.ResultsThe results of multilevel analyses (overall, subgroup and per protocol) showed no statistically significant, nor clinically relevant effects in favor of the intervention group on the behavioral outcome measures.ConclusionsThere is insufficient evidence yet to justify the implementation of emotion‐oriented care on a large scale. Additional studies are needed in which special attention is given to the implementation process. Copyright © 2002 John Wiley & Sons, Ltd.