bluuebunny/crossref_metadata_2025_split huggingface dataset:
An initial assessment of the use of gradient elution in microemulsion and micellar liquid chromatography
Authors: Bryant Simon M. , Altria Kevin D. 
Published: November 2004

AbstractNovel microemulsion and micellar HPLC separations have been achieved using gradient elution and columns packed with reverse phase material. Initial attempts at gradient microemulsion liquid chromatography proved impossible on use of a microemulsion successfully used in capillary electrophoresis. Optimisation of the microemulsion composition allowed the generation of stable microemulsions to achieve separations in HPLC. The novel use of organic‐solvent micellar chromatography in gradient elution mode was shown to give efficient separations. A range of efficient separations of pharmaceuticals and related impurities were obtained. Acidic, basic, and neutral solutes were resolved covering a wide range of water solubilities and polarities. Elution times were in the order of 4–15 minutes. Separations were briefly compared to those accomplished with a micellar HPLC system. It is proposed that gradient elution in both microemulsion and micellar HPLC can be regarded as a highly successful means of achieving resolution of complex mixtures and should be considered for routine analysis and further investigation.
SAGE profiling of UV‐induced mouse skin squamous cell carcinomas, comparison with acute UV irradiation effects
Authors: Rundhaug Joyce E. , Hawkins Kathleen A. , Pavone Amy , Gaddis Sally , Kil Hyunsuk , Klein Russell D. , Berton Thomas R. , McCauley Elisabeth , Johnson David G. , Lubet Ronald A. , Fischer Susan M. , Aldaz C. Marcelo 
Published: November 2004

AbstractUltraviolet (UV) irradiation is the primary environmental insult responsible for the development of most common skin cancers. To better understand the multiple molecular events that contribute to the development of UV‐induced skin cancer, in a first study, serial analysis of gene expression (SAGE) was used to compare the global gene expression profiles of normal SKH‐1 mice epidermis with that of UV‐induced squamous cell carcinomas (SCCs) from SKH‐1 mice. More than 200 genes were found to be differentially expressed in SCCs compared to normal skin (P < 0.0005 level of significance). As expected, genes related to epidermal proliferation and differentiation were deregulated in SCCs relative to normal skin. However, various novel genes, not previously associated with skin carcinogenesis, were also identified as deregulated in SCCs. Northern blot analyses on various selected genes validated the SAGE findings: caspase‐14 (reduced 8.5‐fold in SCCs); cathepsins D and S (reduced 3‐fold and increased 11.3‐fold, respectively, in SCCs); decorin, glutathione S‐transferase omega‐1, hypoxia‐inducible factor 1α, insulin‐like growth factor binding protein‐7, and matrix metalloproteinase‐13 (increased 18‐, 12‐, 12‐, 18.3‐, and 11‐folds, respectively, in SCCs). Chemokine (C‐C motif), ligand 27 (CCL27), which was found downregulated 12.7‐fold in SCCs by SAGE, was also observed to be strongly downregulated 6–24 h after a single and multiple UV treatments. In a second independent study we compared the expression profile of UV‐irradiated versus sham‐treated SKH‐1 epidermis. Interestingly, numerous genes determined to be deregulated 8 h after a single UV dose were also deregulated in SCCs. For instance, genes whose expression was upregulated both after acute UV‐treated skin and SCCs included keratins 6 and 16, small proline‐rich proteins, and S100 calcium binding protein A9. Studies like those described here do not only provide insights into genes and pathways involved in skin carcinogenesis but also allow us to identify early UV irradiation deregulated surrogate biomarkers of potential use in chemoprevention studies. © 2004 Wiley‐Liss, Inc.
A sinh transformation for evaluating nearly singular boundary element integrals
Authors: Johnston Peter R. , Elliott David 
Published: November 2004

AbstractAn implementation of the boundary element method requires the accurate evaluation of many integrals. When the source point is far from the boundary element under consideration, a straightforward application of Gaussian quadrature suffices to evaluate such integrals. When the source point is on the element, the integrand becomes singular and accurate evaluation can be obtained using the same Gaussian points transformed under a polynomial transformation which has zero Jacobian at the singular point.A class of integrals which lies between these two extremes is that of ‘nearly singular’ integrals. Here, the source point is close to, but not on, the element and the integrand remains finite at all points. However, instead of remaining flat, the integrand develops a sharp peak as the source point moves closer to the element, thus rendering accurate evaluation of the integral difficult.This paper presents a transformation, based on the sinh function, which automatically takes into account the position of the projection of the source point onto the element, which we call the ‘nearly singular point’, and the distance from the source point to the element. The transformation again clusters the points towards the nearly singular point, but does not have a zero Jacobian. Implementation of the transformation is straightforward and could easily be included in existing boundary element method software.It is shown that, for the two‐dimensional boundary element method, several orders of magnitude improvement in relative error can be obtained using this transformation compared to a conventional implementation of Gaussian quadrature. Asymptotic estimates for the truncation errors are also quoted. Copyright © 2004 John Wiley & Sons, Ltd.
Uncommon histiocytic disorders: The non‐Langerhans cell histiocytoses
Authors: Weitzman Sheila , Jaffe Ronald 
Published: November 2004

AbstractBackgroundHistiocytic disorders are currently identified by their component cells. The non‐Langerhans Cell Histiocytoses (non‐LCH) are a group of disorders defined by the accumulation of histiocytes that do not meet the phenotypic criteria for the diagnosis of Langerhans cells (LCs). The non‐LCH consist of a long list of diverse disorders which have been difficult to categorize. A conceptual way to think of these disorders that make them less confusing and easier to remember is proposed based on immunophenotyping and clinical presentation.ResultsClinically the non‐LCH can be divided into 3 groups, those that predominantly affect skin, those that affect skin but have a major systemic component, and those that primarily involve extracutaneous sites, although skin may be involved. Immunohistochernically many of the non‐LCH appear to arise from the same precursor cell namely the dermal dendrocyte. Juvenile Xanthogranuloma (JXG) is the model of the dermal dendrocyte‐derived non‐LCH. Other non‐LCH with differing clinical presentation and occurring at different ages but with an identical immunophenotype appear to form a spectrum of the same disorder, deriving from the same precursor cell at different stages of maturation. They should be considered as members of a JXG family. Non‐JXG family members include Sinus histiocytosis with massive lymphadenopathy (Rosai‐Dorfman disease).ConclusionThe non‐LCH can be classified as JXG family and non‐JXG family and subdivided according to fairly clear‐cut clinical criteria. Utilization of this type of approach will allow better categorization, easier review of the literature and more accurate therapy decision‐making. © 2004 Wiley‐Liss, Inc.
Identifying citrus limonoid aglycones by HPLC‐EI/MS and HPLC‐APCI/MS techniques
Authors: Manners Gary D. , Breksa Andrew P. 
Published: November 2004

AbstractHPLC coupled with normal phase electron ionisation (EI) and atmospheric pressure chemical ionisation (APCI)/mass spectrometry methods has been applied to identify 17 known neutral limonoid aglycones from Citrus sources. The HPLC‐MS data from the known limonoids provided chromatographic characteristics, APCI‐derived molecular weight data and EI fragmentation data for each limonoid. EI fragmentation patterns for the limonoids were correlated with structural characteristics. The EI fragmentation patterns coupled with APCI‐derived molecular weights were utilised as a potential method by which to discern the structural character of unknown citrus limonoids. Copyright © 2004 John Wiley & Sons, Ltd.
Alloy and phonon scattering limited mobility in strain‐free ternary Si1–x–yGexCy
Authors: Mukhopadhyay Bratati , Basu P. K. 
Published: November 2004

AbstractEstimates are made of the mobility limited by alloy disorder and phonon scattering mechanisms in strain free Ge‐rich ternary layer Si1–x–yGexCy grown on Si substrate. The expression for alloy scattering potential in ternary was derived for the first time using virtual crystal approximation and it differs from the expressions for ternary and quaternary alloys of III–V compounds. The phonon scattering processes are taken to be identical with those in pure Ge. Conservative estimates of mobility made by using reasonable values of alloy scattering potential indicate that mobility is predominantly limited by alloy scattering for 0.85 < x < 1 and the effect of C mole fraction (y) is not much significant for y < 0.1. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quasi‐localized low‐frequency vibrational modes of disordered solids I. Study by photon echo
Authors: Vainer Yu. G. , Naumov A. V. , Kol'chenko M. A. , Personov R. I. 
Published: November 2004

AbstractAccording to the modern conception, the dynamics of amorphous solids in the intermediate interval of low temperatures (from a few up to dozens of Kelvins) is determined mainly by quasi‐localized low‐frequency vibrational modes (LFMs). Up to now, it is known very little about a nature and properties of these excitations in disordered solids. High‐selective laser spectroscopy of impurity centres, embedded to transparent disordered matrix as a probe, is a very powerful method for deriving information about LFMs. In the two presented papers the results of our photon echo (PE) and single molecule spectroscopy (SMS) studies of LFMs in organic amorphous solids are discussed. In the first part we review the recent results of our PE‐studies. Two cases are analyzed: (a) a coupling of chromophores with a continuous broad spectrum of LFMs, which shape was taken from light scattering experiments, and (b) a coupling of chromophores with continuous LFMs spectra, calculated on the base of the soft potentials model. In the second part we consider the results of our studies of LFMs in a glassy polymer on microscopic level using SMS. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultrafast spectroscopy of localised vibrational modes in amorphous silicon using a free electron laser
Authors: Wells J.‐P. R. , van Hattum E. D. , Schropp R. E. I. , Phillips P. J. , Carder D. A. , Habraken F. H. P. M. , Dijkhuis J. I. 
Published: November 2004

AbstractUltrafast vibrational relaxation of localised modes associated with hydrogen, deuterium and oxygen in amorphous silicon based alloys are discussed. The availability of internal defect vibrations to act as accepting modes is discovered to be a crucial factor in the population decay dynamics. Phase relaxation is shown to have both a temperature dependent component due to elastic phonon scattering as well as an excitation dependence contributed by non‐equilibrium phonons. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy levels of two interacting particles in an anharmonic potential
Authors: Saha B. , Sil A. N. , Das A. K. , Mukherjee P. K. 
Published: November 2004

AbstractEnergy levels of two interacting mass points in an anharmonic model potential (Morse type) have been studied. Analytic expression for the energy levels has been worked out. The model potential is shown to support bound states under certain conditions. The number of such states has been found to depend on the parameters of the potential. The potential is expected to be more realistic, particularly in presence of environments for diatomic molecules and artificial atoms. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
The derivation of the characteristic function and the spectral density distribution of a Hamiltonian of N‐coupled morse oscillators: The large N‐limit
Authors: Bancewicz Małgorzata 
Published: November 2004

AbstractThis paper reports a derivation of the characteristic function and the frequency function of spectral density distribution of a Hamiltonian representing a system of N‐coupled Morse oscillators. The procedure utilized previously evaluated large‐N expressions for spectral density distribution moments. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Ab initio and DFT investigation of the structures and properties of chloromethyl and chlorofluoromethyl peroxyl radicals
Authors: El‐Taher S. 
Published: November 2004

AbstractAb initio and Density Functional Theory (DFT) calculations were performed to determine the equilibrium geometries, charge distributions, spin density distributions, dipole moments, electron affinities (EAs), and C–O bond dissociation energies (BDEs) of CH2ClO2• CHCl2O2•, CCl3O2•, CF2ClO2•, CFCl2O2•, and CHFClO2• peroxyl radicals. The C–H BDEs of the parent methanes were calculated using the same levels of theories. Both MP2(full) and B3LYP methods, using the 6‐31G(d,p) basis set, were found to be capable of accurately predicting the geometries of peroxyl radicals. The B3LYP/6‐31G(d,p) method was found to be comparable to high ab initio levels in predicting C–O BDEs of studied peroxyl radicals and C–H BDEs of the parent alkanes. The progressive chlorine substitution of hydrogen atoms in methyl peroxyl radicals results in an increase (decrease) of the spin density on the terminal (inner) oxygen, a decrease in dipole moments, and an increase in electron affinities. The substitution of fluorine by chlorine in the series CF3O2• – CCl3O2• was found to lengthen (destabilize) the C–O bonds. Both C–O BDEs and EAs of peroxyl radicals (RO2•) were found to correlate well with Taft σ* substituent constants for the R groups. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Does internal water influence electron tunneling in proteins? Example of cytochrome c oxidase
Authors: Zheng Xuehe , Medvedev Dmitry M. , Stuchebrukhov Alexei A. 
Published: November 2004

AbstractIn a recent study, the internal electron transfer in bovine heart cytochrome c oxidase (CcO) was examined using the tunneling currents method at the extended Hückel level of electronic structure. No internal water was present in the published structure of the enzyme, and none was taken into account in the calculations. Through computer simulation, we recently found an intriguing water hydrogen bond network in the vicinity of CcO catalytic site and in the region of electron tunneling. In this work, we reexamine the problem, with the focus on the possibility of the influence of water on electron transfer process. The calculations are carried out with the tunneling currents method implemented using more accurate ZINDO/S quantum chemical model. Results for the electron transfer from heme a to heme a3, a key step in the function of the enzyme, are presented. With molecular dynamics simulations, we identify configurations in which the water molecules interfere with the tunneling pathway. The tunneling matrix element is evaluated by the flux theorem of the tunneling currents method, and is found to be 0.34 cm−1 in the “dry” system and 1.38 cm−1 in the “wet” system. The analysis of the tunneling flux indicates that the impact of water is localized on Phe377 and spread to the methyl group and to His376, both on the heme a3 side of the ET pathway. The increase of the tunneling coupling by a factor of 4 in this case demonstrates that internal water in proteins can influence ET rate in proteins by as much as an order of magnitude. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Tip studies using CFD and comparison with tip loss models
Authors: Hansen Martin O. L. , Johansen Jeppe 
Published: November 2004

AbstractThe flow past a 95 kW Tellus rotor equipped with LM8·2 blades is computed using computational fluid dynamics for a standard tip and a swept tip. The difference in the near‐tip flow for the two tips for various tip speed ratios is examined and 3D airfoil data are extracted. The radial distribution of the averaged axial induction factor and the normal and tangential loads are compared with those of a standard blade element momentum code using 2D calibrated airfoil data for a wind speed of 9 m s−1, where the agreement in computed power is good. Further, a comparison with a new tip loss model proposed by Shen et al. has been performed for the same wind speed. Copyright © 2004 John Wiley & Sons, Ltd.
Aeroelastic stability of wind turbines: the problem, the methods and the issues
Authors: Riziotis V. A. , Voutsinas S. G. , Politis E. S. , Chaviaropoulos P. K 
Published: November 2004

AbstractAeroelastic stability is a key issue in the design process of wind turbines towards both enchanced stability and increased fatigue life. The theory and models behind the state‐of‐the‐art aeroelastic stability tools developed for the analysis of the complete wind turbine at the Centre for Renewable Energy Sources and the National Technical University of Athens are presented in this article. Application examples of stability calculations for a pitch, variable speed and a stall‐regulated wind turbine are also presented. Copyright © 2004 John Wiley & Sons, Ltd.
The effect of roughness at high Reynolds numbers on the performance of aerofoil DU 97‐W‐300Mod
Authors: Timmer W. A. , Schaffarczyk A. P. 
Published: November 2004

AbstractThis article discusses the results of wind tunnel measurements performed on a modified DU 97‐W‐300 aerofoil at Reynolds numbers between 1 × 106 and 10 × 106 in the cryogenic wind tunnel of DNW in Köln, Germany. The aerofoil was modified by reducing the trailing edge thickness from 1·74% to 0·49% of the chord. Although the measurements showed large scatter when flow separation occurred on the model, it was possible to establish the variation with Reynolds number of the maximum lift coefficient, the maximum lift/drag ratio and the design lift coefficient for a Mach number of 0·2. Furthermore, the effect of wrap‐around Carborundum 60 roughness and zigzag tape of 0·4 mm thickness on the upper and lower surfaces was studied. The experimental results were compared with RFOIL calculations. The measurements indicate that there was no significant variation in the maximum lift coefficient with Reynolds number for the clean aerofoil. In contrast to the RFOIL calculations, the experimental maximum lift/drag ratio decreased with increasing Reynolds number from an average of 95 at R = 3 × 106 to about 85 at R = 10 × 106. The Carborundum 60 roughness had a larger negative effect on the aerofoil performance than the zigzag tape, but in both cases the aerofoil performance improved drastically with increasing Reynolds number. Copyright © 2004 John Wiley & Sons, Ltd.
SlidingBayes: exploring recombination using a sliding window approach based on Bayesian phylogenetic inference
Authors: Paraskevis D. , Deforche K. , Lemey P. , Magiorkinis G. , Hatzakis A. , Vandamme A.-M. 
Published: November 2004

Abstract
Summary: We developed a software tool (SlidingBayes) for recombination analysis based on Bayesian phylogenetic inference. Sliding-Bayes provides a powerful approach for detecting potential recombination, especially between highly divergent sequences and complex HIV-1 recombinants for which simpler methods like neighbor joining (NJ) may be less powerful. SlidingBayes guides Markov Chain Monte Carlo (MCMC) sampling performed by MrBayes in a sliding window across the alignment (Bayesian scanning). The tool can be used for nucleotide and amino acid sequences and combines all the modeling possibilities of MrBayes with the ability to plot the posterior probability support for clustering of various combinations of taxa.
Availability: SlidingBayes is available at http://www.kuleuven.ac.be/rega/cev/Software/
Contact: dparask@cc.uoa.gr
Supplementary information: A quick guide and examples for SlidingBayes are available at http://www.kuleuven.ac.be/rega/cev/Software/
PermutMatrix: a graphical environment to arrange gene expression profiles in optimal linear order
Authors: Caraux Gilles , Pinloche Sylvie 
Published: November 2004

Abstract
Summary: PermutMatrix is a work space designed to graphically explore gene expression data. It relies on the graphical approach introduced by Eisen and also offers several methods for the optimal reorganization of rows and columns of a numerical dataset. For example, several methods are proposed for optimal reorganization of the leaves of a hierarchical clustering tree, along with several seriation or unidimensional scaling methods that do not require any preliminary hierarchical clustering. This program, developed for MS Windows, with MS-Visual C++, has a clear and efficient graphical interface. Large datasets can be thoroughly and quickly analyzed.
Availability: http://www.lirmm.fr/~caraux/PermutMatrix/
Contact: caraux@lirmm.fr
Grid Cellware: the first grid-enabled tool for modelling and simulating cellular processes
Authors: Dhar Pawan K. , Meng Tan Chee , Somani Sandeep , Ye Li , Sakharkar Kishore , Krishnan Arun , Ridwan Azmi B.M. , Wah Sebastian Ho Kok , Chitre Mandar , Hao Zhu 
Published: November 2004

Abstract
Summary: Modelling and simulation of complex cellular transactions involve development of platforms that understand diverse mathematical representations and are capable of handling large backend computations. Grid Cellware, an integrated modelling and simulation tool, has been developed to precisely address these niche requirements of the modelling community. Grid Cellware implements various pathway simulation algorithms along with adaptive Swarm algorithm for parameter estimation. For enchanced computational productivity Grid Cellware uses grid technology with Globus as the middleware.
Availability: https://www.bii-sg.org/sbg/cellware
Contact: pk@bii-sg.org
Supplementary information: User Manual is available as PDF file. Examples are attached to expedite mastering of the software.
Status of the Mara Woodlands in Kenya
Authors: Walpole Matthew J. , Nabaala Moriaso , Matankory Charles 
Published: November 2004

AbstractThe woodlands of the Masai Mara National Reserve in Kenya have suffered dramatic declines over four decades as a result of elephant and fire pressure. This study examined the current status of woody resources in the Reserve and browse pressure thereon, using both classification (TWINSPAN) and ordination (DCA) techniques. From 333 widespread regular plots used to survey the vegetation, a total of 62 woody species were identified. Thirteen woody habitats were identified on the basis of species composition, varying from species‐rich closed thickets and forest to less diverse open grasslands. A NW/SE stratification of the more open habitats was observed, possibly as a result of differences in soils, rainfall and drainage. Both plant density and diversity were lower than in communal and privately managed areas outside the Reserve. Moreover, browser pressure was substantially higher than that observed previously in the ecosystem, and suggests increased competition for scarcer woody resources within the Reserve. This has implications for the management of the ecosystem as a whole. As woodland and thickets continue to decline, long‐term monitoring should expand to encompass the wider habitat diversity of the open grasslands and unprotected areas where much of the regeneration potential resides.