bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduction kinetics of Fe(III), Co(III), U(VI), Cr(VI), and Tc(VII) in cultures of dissimilatory metal‐reducing bacteria
Authors: Liu Chongxuan , Gorby Yuri A. , Zachara John M. , Fredrickson Jim K. , Brown Christopher F. 
Published: October 2002

AbstractThe reduction kinetics of Fe(III)citrate, Fe(III)NTA, Co(III)EDTA−, U(VI)O22+, Cr(VI)O42−, and Tc(VII)O4− were studied in cultures of dissimilatory metal reducing bacteria (DMRB): Shewanella alga strain BrY, Shewanella putrefaciens strain CN32, Shewanella oneidensis strain MR‐1, and Geobacter metallireducens strain GS‐15. Reduction rates were metal specific with the following rate trend: Fe(III)citrate ≥ Fe(III)NTA > Co(III)EDTA− > UO22+ > CrO42− > TcO4−, except for CrO42− when H2 was used as electron donor. The metal reduction rates were also electron donor dependent with faster rates observed for H2 than lactate− for all Shewanella species despite higher initial lactate (10 mM) than H2 (0.48 mM). The bioreduction of CrO42− was anomalously slower compared to the other metals with H2 as an electron donor relative to lactate and reduction ceased before all the CrO42− had been reduced. Transmission electron microscopic (TEM) and energy‐dispersive spectroscopic (EDS) analyses performed on selected solids at experiment termination found precipitates of reduced U and Tc in association with the outer cell membrane and in the periplasm of the bacteria. The kinetic rates of metal reduction were correlated with the precipitation of reduced metal phases and their causal relationship discussed. The experimental rate data were well described by a Monod kinetic expression with respect to the electron acceptor for all metals except CrO42−, for which the Monod model had to be modified to account for incomplete reduction. However, the Monod models became statistically over‐parametrized, resulting in large uncertainties of their parameters. A first‐order approximation to the Monod model also effectively described the experimental results, but the rate coefficients exhibited far less uncertainty. The more precise rate coefficients of the first‐order model provided a better means than the Monod parameters, to quantitatively compare the reduction rates between metals, electron donors, and DMRB species. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 637–649, 2002.
Enantiomeric separation of diuretics on a novel pirkle‐type chiral stationary phase
Authors: Vercauteren Ann , Weken Guido Van der , Vankeirsbilck Tineke , Aboul‐Enein Hassan Y. , Baeyens Willy R. G. 
Published: October 2002

AbstractA newly developed Pirkle‐type straight chiral stationary phase (CSP), based on the 3,5‐dinitrobenzoyl derivative of 1,2 diphenylethylene‐diamine and known as ULMO, has been successfully applied to the direct resolution of the enantiomers of several diuretics by liquid chromatography. In this study, the effect of changes in the mobile phase and the intrinsic stereoselective properties of this CSP towards a specific racemate are determined experimentally. A mobile phase consisting of n‐hexane and 2‐propanol appears most appropriate for the chiral separation of the tested diuretics on the ULMO‐column. Copyright © 2002 John Wiley & Sons, Ltd.
A new method for determination of buformin in plasma and urine by ion‐paired reversed‐phase HPLC with ultraviolet detection
Authors: Yamamoto Takehito , Kusama Makiko , Matsuno Kumi , Sugiyama Erika , Yamada Yasuhiko , Iga Tatsuji 
Published: October 2002

AbstractBuformin is a widely used as an antidiabetic agent but its renal excretion is still controversial. A new HPLC method with ultraviolet (UV) detection for the determination of buformin in plasma and urine has been developed. After protein precipitation or dilution, buformin and internal standard phenformin were resolved on an octadecyl silica column and detected by UV detection at 233 nm. Intra‐ and inter‐day coefficients of variation were <9%. The limit of quantification was around 0.05 µg/ml for plasma and 2.5 µg/ml for urine. Copyright © 2002 John Wiley & Sons, Ltd.
Investigation of propofol renal elimination by HPLC using supported liquid membrane procedure for sample preparation
Authors: Dawidowicz Andrzej L. , Kalityński Rafał , Trocewicz Jerzy , Nestorowicz Andrzej , Fijałkowska Anna , Trela‐Stachurska Katarzyna 
Published: October 2002

AbstractOne of the least explored subjects in the research on the metabolism of a widely used anaesthetic, propofol, is its excretion in an unchanged form. According to literature, the estimated percentage of applied propofol eliminated intact via kidneys is lower than 0.3%. The present study shows the amount of propofol excreted in an unchanged form with urine collected during the first 48 h after anaesthesia in five patients undergoing elective intracranial procedures. The drug was concentrated and selectively isolated from urine samples by supported liquid membrane technique and determined by HPLC with fluorescence detection. The amount of unchanged propofol eliminated with urine was approximately (0.004 ± 0.002)% of the total applied dose. The obtained results may suggest that propofol in an unchanged form is not excreted by kidneys at all provided that all propofol determined in presented study originated from conjugates hydrolysis. Copyright © 2002 John Wiley & Sons, Ltd.
The alpha‐factor receptor C‐terminus is important for mating projection formation and orientation in Saccharomyces cerevisiae
Authors: Vallier Laura G. , Segall Jeffrey E. , Snyder Michael 
Published: October 2002

AbstractSuccessful mating of MATa Saccharomyces cerevisiae cells is dependent on Ste2p, the α‐factor receptor. Besides receiving the pheromone signal and transducing it through the G‐protein coupled MAP kinase pathway, Ste2p is active in the establishment and orientation of the mating projection. We investigated the role of the carboxyl terminus of the receptor in mating projection formation and orientation using a spatial gradient assay. Cells carrying the ste2‐T326 mutation, truncating 105 of the 135 amino acids in the receptor tail including a motif necessary for its ligand‐mediated internalization, display slow onset of projection formation, abnormal shmoo morphology, and reduced ability to orient the mating projection toward a pheromone source. This reduction was due to the increased loss of mating projection orientation in a pheromone gradient. Cells with a mutated endocytosis motif were defective in reorientation in a pheromone gradient. ste2‐Δ296 cells, which carry a complete truncation of the Ste2p tail, exhibit a severe defect in projection formation, and those projections that do form are unable to orient in a pheromone gradient. These results suggest a complex role for the Ste2p carboxy‐terminal tail in the formation, orientation, and directional adjustment of the mating projection, and that endocytosis of the receptor is important for this process. In addition, mutations in RSR1/BUD1 and SPA2, genes necessary for budding polarity, exhibited little or no defect in formation or orientation of mating projections. We conclude that mating projection orientation depends upon the carboxyl terminus of the pheromone receptor and not the directional machinery used in budding. Cell Motil. Cytoskeleton 53:251–266, 2002. © 2002 Wiley‐Liss, Inc.
Rescue of a Chlamydomonas inner‐arm‐dynein‐deficient mutant by electroporation‐mediated delivery of recombinant p28 light chain
Authors: Hayashi Masahito , Yanagisawa Haru‐aki , Hirono Masafumi , Kamiya Ritsu 
Published: October 2002

AbstractWe have recently shown that rabbit actin can be introduced by electroporation into the Chlamydomonas ida5 mutant lacking conventional actin and rescue its mutant phenotype [Hayashi et al., 2001: Cell Motil. Cytoskeleton 49:146–153]. In this study, we explored the possibility of using electroporation for functional assay of a recombinant protein. The p28 light chain of inner‐arm dyneins was expressed in Escherichia coli, purified to homogeneity, and introduced by electroporation into a non‐motile mutant ida4oda6 that lacks it. Because this protein was insoluble in the low ionic strength solution used in the previous study, electroporation was performed at physiological ionic strength in the presence of Ca2+. Most cells shed their flagella after electroporation. Reflagellation took place within 3 h and up to 30% of the cells became motile, indicating that the introduced p28 retained its functional activity. Fluorescently‐labeled p28 was equally effective; in this case fluorescence was observed along the flagella. The presence of Ca2+ and deflagellation appeared to be important for efficient protein delivery, because a triple mutant with the fa1 mutation deficient in the flagellar shedding mechanism recovered motility only very poorly. Similar results were obtained with other combinations of recombinant proteins and mutants. This study thus demonstrates the feasibility of using electroporation for activity assays of recombinant proteins. Cell Motil. Cytoskeleton 53:273–280, 2002. © 2002 Wiley‐Liss, Inc.
Transient expression of the t‐isoform of plastins/fimbrin in the stereocilia of developing auditory hair cells
Authors: Daudet Nicolas , Lebart Marie‐Christine 
Published: October 2002

AbstractThe transduction of auditory signals by cochlear hair cells depends upon the integrity of hair cell stereociliary bundles. Stereocilia contain a central core of actin filaments, cross‐linked by actin bundling proteins. In the cochlea, the two proteins described to date as responsible for the spatial arrangement of actin filaments in sterocilia are fimbrin and the recently discovered espin. Fimbrin (the chick homolog of human I‐plastin) belongs to the plastins/fimbrin family that includes two additional isoforms of plastins, T‐ and L‐plastin. In the present study, we used isoform specific antibodies to investigate the presence of the T‐ and L‐isoforms of plastin/fimbrin in the adult and developing rat cochlea. We found that T‐plastin, but not L‐plastin, is expressed in the rat cochlea. During postnatal development of the rat organ of Corti, T‐plastin can be detected in the core of stereocilia from early stages of hair cell differentiation, and its expression gradually increases in stereocilia as hair cells mature. However, as opposed to other actin‐binding proteins expressed in stereocilia, T‐plastin is absent from the stereocilia of mature hair cells. Such temporally restricted expression strengthens the idea of functional differences between plastins isoforms, and suggests that T‐plastin could have a specific role in stereocilia formation. Cell Motil. Cytoskeleton 53:326–336, 2002. © 2002 Wiley‐Liss, Inc.
Optimization of heat sink mass using the DYNAMIC‐Q numerical optimization method
Authors: Visser J. A. , de Kock D. J. 
Published: October 2002

AbstractHeat sink designers have to balance a number of conflicting parameters to maximize the performance of a heat sink. This must be achieved within the given constraints of size or volume of the heat sink as well as the mass or material cost of the heat sink. This multi‐parameter problem lends itself naturally to optimization techniques. Traditionally, an experimental approach was used where different heat sink designs were constructed and their performance measured. This approach is both time consuming and costly. More recently, numerical CFD techniques have been used, but mostly on a trial‐and‐error basis, and is basically the numerical equivalent of the experimental approach. A better approach is to combine a semi‐empirical simulation program with mathematical optimization techniques. This paper describes the use of mathematical optimization techniques to minimize heat sink mass. The simulation uses the Qfin 2.1 code, while the optimization is carried out by means of the DYNAMIC‐Q method. This method is extremely robust and specifically designed to handle constrained problems where the objective and/or constraint functions are expensive to evaluate. The paper illustrates how the parameters considered influence the heat sink mass and how mathematical optimization techniques can be used by the heat sink designer to design compact heat sinks for different types of electronic enclosures. Copyright © 2002 John Wiley & Sons, Ltd.
Signal processing challenges for applying software radio principles in future wireless terminals: an overview
Authors: Valkama Mikko , Pirskanen Juho , Renfors Markku 
Published: October 2002

AbstractThe general idea of software radio is to develop highly integrated radio transceiver structures with high degree of flexibility and multimode capabilities, achieved through increased role of digital signal processing software in defining the functionalities which have traditionally been implemented with analog RF techniques. This paper explores the software radio concept from the receiver architecture and signal processing points of view, with mainly the wireless terminal application in mind. We first discuss the critical issues in alternative receiver architectures with simplified analog parts and increased configurability. We also introduce certain advanced digital signal processing techniques which could potentially relieve some of the essential problems and pave the way towards DSP‐based, highly integrated, and highly configurable terminals. Big emphasis is on efficient digital multirate signal processing methods and complex (I/Q) signal processing. Copyright © 2002 John Wiley & Sons, Ltd.
Higher order finite element methods and multigrid solvers in a benchmark problem for the 3D Navier–Stokes equations
Authors: John Volker 
Published: October 2002

AbstractThis paper presents a numerical study of the 3D flow around a cylinder which was defined as a benchmark problem for the steady state Navier–Stokes equations within the DFG high‐priority research program flow simulation with high‐performance computers by Schafer and Turek (Vol. 52, Vieweg: Braunschweig, 1996). The first part of the study is a comparison of several finite element discretizations with respect to the accuracy of the computed benchmark parameters. It turns out that boundary fitted higher order finite element methods are in general most accurate. Our numerical study improves the hitherto existing reference values for the benchmark parameters considerably. The second part of the study deals with efficient and robust solvers for the discrete saddle point problems. All considered solvers are based on coupled multigrid methods. The flexible GMRES method with a multiple discretization multigrid method proves to be the best solver. Copyright © 2002 John Wiley & Sons, Ltd.
Adsorption of dyes and humic acid from water using chitosan‐encapsulated activated carbon
Authors: Wu Feng‐Chin , Tseng Ru‐Ling , Juang Ruey‐Shin 
Published: October 2002

AbstractThe adsorption isotherms and rates of two dyes and humic acid from aqueous solutions onto chitosan‐encapsulated activated carbon (CEAC) beads were measured at 30 °C. Such beads were prepared by mixing different weight percents of cuttlefish‐based chitosan (100%, 80%, 67%, and 55%) and rice‐based activated carbons. It was shown that the isotherms of dyes and humic acid were well fitted by the Freundlich equation. The adsorption capacity and rate could be enhanced when activated carbon was encapsulated with chitosan. Four simplified kinetic models including the pseudo‐first‐order equation, pseudo‐second‐order equation, intraparticle diffusion model, and the Elovich equation were tested to follow the adsorption processes. The adsorption of dyes was best described by the Elovich equation, but that of humic acid was best described by the intraparticle diffusion model. The kinetic parameters of each best‐fit model were calculated and are discussed in this paper.© 2002 Society of Chemical Industry
Improvements and algorithmical considerations on a recent three‐dimensional model describing stress‐induced solid phase transformations
Authors: Auricchio Ferdinando , Petrini Lorenza 
Published: October 2002

AbstractDuring mechanical loading–unloading cycles shape‐memory alloys (SMA) are able to undergo large deformations without showing residual strains (pseudoelasticity) or recovering them through thermal cycles (shape memory effect). Motivated by stress‐induced solid phase transformations, these unique behaviours induce the SMA exploitation in innovative and commercially valuable applications, stimulating, consequently, the interest in the development of constitutive models. Also if many models are now available in the literature, effective three‐dimensional proposals are still few and limited in several aspects.In this paper, a three‐dimensional thermomechanical model recently proposed by Souza et al. (European Journal of Mechanics–A/Solids, 1998; 17: 789–806.) is taken into consideration; such a model is of particular interest for its effectiveness and flexibility, but it also shows some limitations and missing links in the algorithmical counterparts.This work discusses some improvements to the original model as well as the development and the implementation of a robust integration algorithm to be adopted in a numerical scheme, such as a finite‐element framework. Copyright © 2002 John Wiley & Sons, Ltd.
Role of fetal sex in amniotic fluid alphafetoprotein screening
Authors: Knippel Alexander Johannes 
Published: October 2002

AbstractObjectivesPrevious studies have shown that fetal gender has influence on various pregnancy complications and prenatal diagnostic biochemical markers. We have evaluated, whether elevation of amniotic fluid alphafetoprotein (AF AFP) is associated with fetal sex and whether a sex‐related difference can help to identify pregnancies with AFP‐associated malformations or fetal loss.Material and methodsFrom our database we obtained 6461 singleton gestations with AF AFP measurements for the period April 1997–March 1999. Patients with AF AFP >1.9 MoM were identified, details of pregnancy outcome were obtained and compared to matched‐pair controls having AF AFP <2 MoM.ResultsIn 232 of 262 patients having AF AFP levels >1.9 MoM outcome information was available. Of these fetuses, significantly more had male gender (147 male fetuses versus 85 female). Having a screen‐positive result the risk of AFP‐associated malformations was significantly higher for female fetuses (25 female fetuses (29.4%) versus 22 male fetuses (15%) with AFP‐associated malformations). Adjusting the cut‐off MoM to 2.5 for male and to 2.0 for female fetuses halves the false positive rate from 3.4 to 1.7% without affecting the detection rate of 95%.Pregnancies with false positive AF AFP had a significantly higher risk for fetal loss compared with pregnancies having normal AF AFP (ten fetal losses from 185 versus two fetal losses from 232), but fetal gender had no significant influence.ConclusionsAdjusting AF AFP MoM cut‐offs for fetal gender could increase performance of AF‐AFP screening. Larger studies are required to determine suitable sex‐adjusted cut‐off levels. Copyright © 2002 John Wiley & Sons, Ltd.
Between pregnancy biological variability of first trimester markers of Down syndrome and the implications for screening in subsequent pregnancies: an issue revisited
Authors: Spencer Kevin 
Published: October 2002

AbstractObjectivesTo assess the level of correlation of first trimester biochemical and biophysical markers of Down syndrome between different pregnancies in the same individual. To assess the impact that between pregnancy biological variability has on the likelihood that women who are at increased risk in a first pregnancy being also at increased risk in a subsequent pregnancy.MethodsDuring a three period women attending the OSCAR clinic at Harold Wood Hospital have had the opportunity to have first trimester screening for Down syndrome and other aneuploidies using the maternal serum biochemical markers free β‐human chorionic gonadotrophin (hCG) and pregnancy associated plasma protein‐A (PAPP‐A) in conjunction with fetal nuchal translucency (NT) thickness and maternal age. Of the 11 1105 women undergoing such screening, the computer records were examined for women who had more than one pregnancy. The results from 1002 women with two normal singleton pregnancies were available for analysis. Marker correlations (as MoM) were established between the pregnancies and the proportion of women likely to be at increased risk in each pregnancy estimated, as was the likelihood of women being at increased risk in both pregnancies.ResultsFor fetal NT there was no correlation between NT MoM in the first and second pregnancy (r = 0.0959, p > 0.10). For maternal serum free β‐hCG MoM a significant correlation was found (r = 0.3976, p < 0.001), as was also found for PAPP‐A MoM (r = 0.4371, p < 0.001).ConclusionThe implication for such between pregnancy marker association is that women who have an increased risk of Down syndrome in one pregnancy are two or three times more likely to repeat this event in their next pregnancy. This information may be useful in counselling women when undergoing first trimester screening in a subsequent pregnancy. Copyright © 2002 John Wiley & Sons, Ltd.
Issues surrounding prenatal genetic testing for achondroplasia
Authors: Gooding Holly C. , Boehm Karina , Thompson Richard E. , Hadley Don , Francomano Clair A. , Biesecker Barbara Bowles 
Published: October 2002

AbstractObjectivesMutations in the gene encoding fibroblast growth factor receptor 3 cause achondroplasia, the most prevalent form of dwarfism. Since the discovery of the mutations and gene in 1994, commercial testing has been available for use in prenatal diagnosis. This study sought to determine the awareness of, interest in and use of prenatal genetic testing for achondroplasia.MethodsSurveys were collected from both individuals affected with achondroplasia (n = 189) and their average statured relatives (n = 136).ResultsThe majority of participants were aware of the prenatal genetic testing at the time they were surveyed, but less than 10% had actually used the testing. Affected individuals were much more interested in using the testing if they became pregnant (62%) than were their relatives (28%). The groups were remarkably similar in their interest in using the testing to identify the lethal, homozygous form of achondroplasia and in their unwillingness to consider termination of pregnancies based on a diagnosis of either achondroplasia or average stature. Affected status and perception of the condition were correlated with the importance placed on knowing the prenatal diagnoses of achondroplasia and average stature. Views on abortion were highly correlated with all aspects of interest in prenatal diagnosis for achondroplasia.ConclusionThese results elucidate the role of selected attitudes and beliefs that contribute to reproductive decision making about achondroplasia. Furthermore, the findings provide insights into education and counseling issues for families and health care practitioners. Copyright © 2002 John Wiley & Sons, Ltd.
Beam injection methods for characterizing thin‐film solar cells
Authors: Romero Manuel J. , Al‐Jassim Mowafak M. , Dhere Ramesh G. , Hasoon Falah S. , Contreras Miguel A. , Gessert Timothy A. , Moutinho Helio R. 
Published: October 2002

AbstractII–VI and I–III–VI solar cells are promising for future thin‐film photovoltaics. In this paper, the roles of electron‐beam‐induced current (EBIC) and cathodoluminescence in evaluating the influence of interfaces on those solar cells are reviewed. CdTe and Cu(In,Ga)Se2(CIGS) are the absorbers of the cells investigated. For CdTe/CdS solar cells, a detailed study has been conducted of the effects of grain boundaries and the Te/CdTe or ZnTe:Cu/CdTe interfaces for back‐contacting. For CIGS solar cells, we have investigated different buffer layer schemes, showing that these interfaces are critical in the definition of the mechanisms for carrier collection. Copyright © 2002 John Wiley & Sons, Ltd.