bluuebunny/crossref_metadata_2025_split huggingface dataset:
Capillary zone electrophoresis study of cyclodextrin – lipoic acid host‐guest interaction
Authors: Trentin Marco , Carofiglio Tommaso , Fornasier Roberto , Tonellato Umberto 
Published: December 2002

AbstractLipoic acid is a naturally occurring compound which is being widely investigated for its therapeutic effects in the treatment or prevention of a variety of diseases associated with oxidative injury, particularly diabetes. The diversity of therapeutic applications of lipoic acid requires an appropriate formulation to control its bioavailability, site‐targeting delivery and to overcome its inherent chemical instability. In this regard, cyclodextrins (CDs) are ideally suitable due to their well‐documented ability to include in their cavity proper guest molecules and protect them from physical or chemical damages. Lipoic acid forms 1:1 inclusion complexes with βCD as shown in a previous report of an extended investigation that also indicated the suitability of capillary zone electrophoresis (CZE) for the study of such host‐guest interactions. In view of these possible applications, we extended the CZE analysis to determine the strength of binding, in a pH 9 phosphate buffer, of lipoic acid with other CD derivatives such as αCD, γCD and the alkylated derivatives of βCD, namely (2‐hydroxypropyl)‐β‐CD (HPβCD), and heptakis(2,3,6‐tri‐O‐methyl)‐β‐CD (TMβCD). Once established that the easily available βCD is the most suitable receptor for lipoic acid, we set up and here describe a simple and reliable procedure for the quantitative determination of lipoic acid in commercial dietary supplement tablets containing also other active substances and excipients.
Histone deacetylase dHDAC4 is involved in segmentation of the Drosophila embryo and is regulated by gap and pair‐rule genes
Authors: Zeremski Marija , Stricker Jason R. , Fischer Denise , Zusman Susan B. , Cohen Dalia 
Published: December 2002

AbstractSummary: Histone deacetylases (HDACs) are catalytic subunits of multiprotein complexes that are targeted to specific promoters through their interaction with different transcriptional repressors causing silencing of the corresponding genes. This study describes the isolation of dHDAC4, a novel, catalytically active class II Drosophila histone deacetylase, and the analysis of its role in embryonic development. In early embryos, dHDAC4 is expressed in several phases. Initial ubiquitous expression becomes localized to an anterior domain, then evolves into a pair‐rule‐like and finally into a segment‐polarity‐like pattern. Suppression of dHDAC4 during early embryogenesis by double‐stranded RNA interference led to segmentation defects. Analysis of dHDAC4 expression in gap and pair‐rule gene mutants demonstrated that hunchback, knirps, and giant activate, while even‐skipped suppresses dHDAC4 expression. These data revealed dHDAC4 involvement in the segmentation regulatory pathway and suggested complex transcriptional regulation as a potential mechanism that controls its expression. genesis 35:31–38, 2003. © 2002 Wiley‐Liss, Inc.
Boundary‐layer integration approach to advection of sensible heat to a patchy snow cover
Authors: Granger R. J. , Pomeroy J. W. , Parviainen J. 
Published: December 2002

AbstractIn the calculation of the melting of a patchy snow cover, the energy advected from the adjacent bare soil to the snow surface is an important consideration. The quantity or rate of energy advected depends on the fetches and sizes of snow and bare ground patches. Any successful method to estimate advection will necessarily require the incorporation of relationships describing the same. Complex boundary‐layer methods require detailed spatial knowledge of the patch sizes, wind direction and fetch distances, and are computationally intensive. A physically based approach that can be spatially applied using distributions of snow patch geometry is required.This paper presents a new approach, in which boundary‐layer integration is used to provide a means of calculating the amount of energy removed by the snow patch surface as warmer air moves over it. The method is reduced to a simple parametric form, and the relationships describing the coefficients required for its application are developed.The applicability of this new approach is discussed in light of the fractal nature of snow patches, the relationship between the individual patch length and area, and the distribution of patch sizes as they develop and disappear on the landscape. Copyright © 2002 Crown in the right of Canada. Published by John Wiley & Sons Ltd.
An efficient snow albedo model for the open and sub‐canopy
Authors: Melloh Rae A. , Hardy Janet P. , Bailey Ronald N. , Hall Tommie J. 
Published: December 2002

AbstractA new model is presented for simulating snow surface albedo in the open and beneath a mixed‐forest canopy. The model has modest input data requirements and is an efficient physically based parameterization that includes the dependency of albedo on solar zenith angle, cloud cover, canopy, snow grain size, litterfall, snowfall, snow depth, and partial snow cover. Measurements used in the model validation include incident spectral irradiances, wavelength‐integrated visible and near‐infrared albedos, snowfall records, snow depth, snow surface litter fractions, and quantity of fine litter in snow cores. Measured and modelled forest snow albedos were less than open snow albedos during the accumulation phase, when there was little or no surface litter. The model predicts lower albedos in the forest during the accumulation phase because of a spectral shift to less reflective wavelengths of incident radiation under the canopy. Snow grain size was important during both the accumulation and ablation phases. Surface litter fraction, incident spectra, snowpack depth, and partial snow cover were important factors lowering forest albedo during ablation. Despite lower mid‐winter albedos in the forest, the snow melted more rapidly in the open. During late ablation, snow albedo in the open became lower than snow albedo in the forest, because of the thinner snow in the open. At the end of the ablation season, partial snow cover affected the albedo in the forest over a longer time period than in the open. Additional work is needed to improve the physical basis of the grain growth model used here and to develop a spatial albedo model for open and forested terrain. Published in 2002 by John Wiley & Sons Ltd.
An assessment of the differences between three satellite snow cover mapping techniques
Authors: Bitner David , Carroll Tom , Cline Don , Romanov Peter 
Published: December 2002

AbstractThe National Operational Hydrologic Remote Sensing Center (NOHRSC) of the National Oceanic and Atmospheric Administration's (NOAA's) National Weather Service (NWS) provides daily satellite‐derived snow cover maps to support the NWS Hydrologic Services Program covering the coterminous USA and Alaska. This study compared the NOHRSC snow cover maps with new automated snow cover maps produced by the National Environmental Satellite, Data, and Information Service (NESDIS) and the snow cover maps created from the Moderate Resolution Imaging Spectroradiometer (MODIS) imagery. The purpose of this paper is to demonstrate and account for the differences that occur between the three different snow cover mapping techniques. Because each of these snow cover products uses data from different sensors at different resolutions, the data were degraded to the coarsest relevant resolution. In both comparisons, forest canopy density was examined as a possible explanatory factor to account for those differences. NOHRSC snow cover maps were compared with NESDIS snow cover maps for 32 different dates from November 2000 to February 2001. NOHRSC snow cover maps were also compared with MODIS snow cover maps in the Pacific Northwest and the Great Plains for 18 days and 21 days, respectively, between March and June 2001. In the first comparison, where the NOHRSC product (∼1 km) was degraded to match the resolution of the NESDIS data (∼5 km), the two products showed an average agreement of 96%. Forest canopy density data provided only weak explanation for the differences between the NOHRSC and the NESDIS snow cover maps. In the second comparison, where the MODIS product (∼500 m) was degraded to match the resolution of the NOHRSC product for two sample areas, the agreement was 94% in the study area in the Pacific Northwest, and 95% in the study area in the Great Plains. Published in 2002 by John Wiley & Sons, Ltd.
Development of a historical ice database for the study of climate change in Canada
Authors: Lenormand Frédéric , Duguay Claude R. , Gauthier Roger 
Published: December 2002

AbstractThe Canadian government has been compiling various observations on freshwater and coastal sea ice conditions for many years. However, the records are not easily accessible and are dispersed within different government departments. Given this, a major effort was undertaken in order to gather all available observations into a common database—the Canadian Ice Database (CID). This database will respond to the needs for climate monitoring in Canada, the validation and improvement of numerical ice models and the development of new remote‐sensing methods. Indeed, several studies have shown that freshwater ice and sea ice are good proxy indicators of climate variability and change.The first version of CID contains in situ observations from 757 sites distributed across Canada, which were originally kept on digital or paper records at the Meteorological Service of Canada Headquarters and the Canadian Ice Service (CIS). The CID holds 63 546 records covering the period from ice season 1822–23 to 2000–01. An analysis of the database allows one to trace the temporal evolution of the ice networks. The freeze‐up/break‐up network of 2000–01 only represents 4% of what it was in 1985–86. A drastic decline of the ice thickness and the snow on ice network is also observable. In 1997–98, it represented only 10% of the network that existed in 1984–85. The major budget cuts in Canadian government agencies during the late 1980s and the 1990s offer the most plausible explanation for the drastic decline in the ice observation networks. Weekly ice coverage determination on large lakes from satellite imagery by the CIS and the national volunteer ice monitoring program, IceWatch, may provide a means of reviving, at least, the freeze‐up/break‐up network. Copyright © 2002 John Wiley & Sons, Ltd.
Simulation of terrain and forest shelter effects on patterns of snow deposition, snowmelt and runoff over a semi‐arid mountain catchment
Authors: Marks Danny , Winstral Adam , Seyfried Mark 
Published: December 2002

AbstractIn mountainous regions, topographic structure and vegetation control patterns of snow deposition, climate conditions, and snowmelt. A topographically distributed snow accumulation and melt model (ISNOBAL) was coupled to a wind field and snow redistribution model to simulate the development and ablation of the seasonal snow cover over a small mountainous catchment, the Reynolds Mountain East basin (0·38 km2) in southwestern Idaho, USA. The model was driven by hourly terrain‐ and canopy‐corrected data grids derived from meteorological data from two stations located within the catchment for four water years (1986, 1987, 1989 and 1997). The catchment was divided into four shelter classes, based on terrain and vegetation; these were used for an analysis of how the mass and energy balance of the snowcover varies over the basin as a function of terrain and forest characteristics for each of the selected years. As shown by the simulations and verified by detailed point measurements and the late‐season areal photographs of snow‐covered area, in all years the wind‐exposed areas developed thinner snow covers and were essentially bare of snow prior to the onset of spring meltout in wind‐sheltered areas. The meltout of the wind‐sheltered drift and canopy‐enclosed regions occurred in conjunction with the springtime increase in solar radiation generating the bulk of springtime runoff. Melt contributions from the drifts may continue into the late spring and early summer. This research uses a unique set of point and spatial verification data to show that a snow accumulation and ablation model, adjusted for wind redistribution effects, reliably simulated the topographic and vegetation influences on snow distribution, the energy balance, and the hydrology of snow and wind‐dominated mountainous regions. Published in 2002 by John Wiley & Sons, Ltd.
Comparison of spatial interpolation methods for estimating snow distribution in the Colorado Rocky Mountains
Authors: Erxleben Jennifer , Elder Kelly , Davis Robert 
Published: December 2002

AbstractOur understanding of snow distribution in the mountains is limited as a result of the complex controls leading to extreme spatial variability. More accurate representations of snow distribution are greatly needed for improvements to hydrological forecasts, climate models, and for the future testing and validation of remote‐sensing retrieval algorithms. In this study, the relative performances of four spatial interpolation methods were evaluated to estimate snow water equivalent for three 1 km2 study sites in the Colorado Rocky Mountains. Each study site is representative of different topographic and vegetative characteristics. From 1 to 11 April 2001, 550 snow depth measurements and approximately 16 snow density profiles were obtained within each study site. The analytical methods used to estimate snow depth over the 1 km2 areas were (1) inverse distance weighting, (2) ordinary kriging, (3) modified residual kriging and cokriging, and (4) a combined method using binary regression trees and geostatistical methods. The independent variables used were elevation, slope, aspect, net solar radiation, and vegetation. Using cross‐validation procedures, each method was assessed for accuracy. The tree‐based models provided the most accurate estimates for all study sites, explaining 18–30% of the observed variability in snow depth. Kriging of the regression tree residuals did not substantially improve the models. Cokriging of the residuals resulted in a less accurate model when compared with the tree‐based models alone. Binary regression trees may have generated the most accurate estimates out of all methods evaluated; however, substantial portions of the variability in observed snow depth were left unexplained by the models. Though the data may have simply lacked spatial structure, it is recommended that the characteristics of the study sites, sampling strategy, and independent variables be explored further to evaluate the causes for the relatively poor model results. Copyright © 2002 John Wiley & Sons, Ltd.
4‐Hydroxytamoxifen sulfation metabolism
Authors: Chen Guangping , Yin Shuhua , Maiti Smarajit , Shao Xiuping 
Published: December 2002

AbstractTamoxifen (TAM) is an important chemotherapeutic agent for the treatment of breast cancer. It has also been shown to decrease breast cancer incidence in healthy women at high risk for the disease. The increased risk of endometrial cancer in women has raised concerns in the use of the drug. Tamoxifen has also been shown to be a potent hepatocarcinogen in rats. The oxidative metabolites of TAM include α‐hydroxytamoxifen (α‐OH‐TAM) and 4‐hydroxytamoxifen (4‐OH‐TAM). The studies on the sulfation of these metabolites are very limited. It has been reported that α‐OH‐TAM is a substrate for rat hydroxysteroid sulfotransferase a (STa). Our studies on the sulfation of 4‐OH‐TAM demonstrated that 4‐hydroxytamoxifen can be sulfated by human liver and human intestinal cytosols. Human phenol‐sulfating sulfotransferase and human estrogen sulfotransferase are the major enzymes for the sulfation of 4‐OH‐TAM. Human dopamine‐sulfating sulfotransferase also has sulfation activity for 4‐OH‐TAM. In contrast, rat liver and intestine cytosols have no detectable sulfation activity for 4‐OH‐TAM. The results suggest that the α‐OH‐TAM sulfation pathway leads to bioactivation of TAM, and the 4‐OH‐TAM sulfation pathway leads to detoxification of TAM. This agrees with the fact that TAM is more toxic for rats than for human beings. © 2002 Wiley Periodicals, Inc. J Biochem Mol Toxicol 16:279–285, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10048
Predicting early career research productivity: the case of management faculty
Authors: Williamson Ian O. , Cable Daniel M. 
Published: December 2002

AbstractWe used a longitudinal design to examine the predictors of early career research productivity for 152 management professors over the first six years of their career. Results revealed early career research productivity to be a function of dissertation advisor research productivity, pre‐appointment research productivity, and the research output of a faculty member's academic origin and academic placement. However, the effects of these predictors varied over time in terms of strength. The findings are discussed in terms of guiding the evaluation and hiring of new researchers in knowledge‐based industries. Copyright © 2003 John Wiley & Sons, Ltd.
Beliefs about ‘improvability’ of career‐relevant skills: relevance to job/task analysis, competency modelling, and learning orientation
Authors: Maurer Todd J. , Wrenn Kimberly A. , Pierce Heather R. , Tross Stuart A. , Collins William C. 
Published: December 2002

AbstractBased on data obtained from three samples of participants from both a work organization and a college setting, this paper addressed two major research objectives relevant to organizational behavior and applied psychology. First, we wanted to explore the nature of implicit theory of skill malleability in more detail than has been done before. This was done by drawing on KSAO dimensions from the task/job analysis literature, and examining linkages among: (a) task/job analysis; (b) implicit theories; and (c) competency modelling (an area in which there has been little empirical research). The studies found multiple factors of beliefs about KSAO improvability and showed a clear ordering of improvability beliefs (from most to least improvable) that follow predictions made in the Iceberg model of competencies. The present studies also found relationships between perceptions of KSAO importance and KSAO improvability, as well as evidence that this relationship is stronger for people who have been in a role/job longer, having had greater opportunity to observe critical KSAOs improve over time. A second major objective of the research was to explore improvability beliefs within a nomological network that would help to further establish the construct validity of the beliefs within the learning/development area. Using structural modelling, the improvability beliefs were tied to learning‐oriented concepts including self‐efficacy for learning and development, tendency to compare oneself to others when learning, as well as learning‐oriented attitudes and behaviors. The potential practical value of improvability beliefs is discussed, as are suggestions for future research. Copyright © 2003 John Wiley & Sons, Ltd.
Corrosion of coating materials in oxidizing and hydrogen chloride containing atmospheres
Authors: Cha S.C. , Wölpert P. 
Published: December 2002

AbstractThe boiler tubes in waste incinerator plants and power plants are mainly corrosive strained. This paper presents the corrosion behaviour of various coating materials in two corrosive atmospheres at 500°C. In a first test, Ni‐based materials applied by High Velocity Oxygen Fuel Flame (HVOF)‐spraying and Atmospheric Plasma Spraying (APS) as well as Cr‐based materials obtained by diffusion coating process are tested in oxidizing atmosphere with water saturation. The results of the corrosion test in this H2O‐O2‐N2‐atmosphere show that NiCr applied by HVOF is less oxidized than that applied by APS‐coating, whereas NiCrBSi coating by APS shows higher resistance than that applied by HVOF‐spraying. The diffusion coating of Cr/Si is better than that of pure Cr. In a second test, metallic Mo and W‐based materials applied by thermal spraying are tested to verify their corrosion resistance in HCl‐H2O‐O2‐N2‐atmosphere. It is shown that pure Mo applied by APS on 13 CrMo 44 and WCrNi sprayed on 15 Mo 3 by HVOF as well as on 13 CrMo 44 show relatively high corrosion resistance, whereas Mo sprayed by APS on 15 Mo 3 is not resistant. Both tungsten‐cobalt‐chromium mixtures show extremely high oxidation rates. Base materials in both tests were the standard boiler tube materials 15 Mo 3 and 13 CrMo 44. But even the low corrosion rates of the best materials in these tests are higher compared to those of materials already presented by Cha et al. in an earlier paper.
A preliminary investigation on an ELLAM scheme for linear transport equations
Authors: Al‐Lawatia Mohamed , Wang Hong 
Published: December 2002

AbstractWe present an Eulerian‐Lagrangian localized adjoint method (ELLAM) for linear advection‐reaction partial differential equations in multiple space dimensions. We carry out numerical experiments to investigate the performance of the ELLAM scheme with a range of well‐perceived and widely used methods in fluid dynamics including the monotonic upstream‐centered scheme for conservation laws (MUSCL), the minmod method, the flux‐corrected transport method (FCT), and the essentially non‐oscillatory (ENO) schemes and weighted essentially non‐oscillatory (WENO) schemes. These experiments show that the ELLAM scheme is very competitive with these methods in the context of linear transport PDEs, and suggest/justify the development of ELLAM‐based simulators for subsurface porous medium flows and other applications. © 2002 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 22–43, 2003
Pharmacoepidemiologic implications of erroneous varicella vaccinations in pregnancy through confusion with Varicella zoster immune globulin
Authors: Wise Robert P. , Braun M. Miles , Seward Jane F. , Mootrey Gina Terracciano , Shields Kristine E. , Salive Marcel E. , Krause Philip R. 
Published: December 2002

AbstractA series of case reports to the varicella vaccine Pregnancy Registry described inadvertent administrations during pregnancy of this live virus product instead of the intended Varicella zoster immune globulin. Cases continued to accrue despite an early publication about the pattern. The persistent problem warrants specific educational efforts to prevent further repetitions. It also has more general implications for medical product safety surveillance. First, this problem's original detection depended on the Pregnancy Registry's open‐ended collection of information about pregnancy exposures. It could have escaped recognition through surveillance limited to pre specified potential risks. This need for unrestricted reporting and human vigilance to sift through case stories has particular relevance for efforts to re‐think methods to monitor gestational drug exposures. In addition, the problem's persistence despite initial publicity suggests that diligent surveillance may require continued follow‐up of identified safety issues. Periodic reassessments of selected preventable problems might strengthen efforts to minimize product risks. Copyright © 2002 John Wiley & Sons, Ltd.