bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of comprehensive two‐dimensional gas chromatography mass spectrometry and different types of data analysis for the investigation of cigarette particulate matter
Authors: Gröger Thomas , Welthagen Werner , Mitschke Stefan , Schäffer Marion , Zimmermann Ralf 
Published: October 2008

AbstractIn tobacco research, the comparison of different tobacco blends as well as the puff‐dependent behaviour of cigarettes is a matter of particular interest. For the investigation of smoke characteristics, GC×GC offers different ways for data analysis, namely, compound target analysis, automated peak‐based compound classification and comprehensive pixel‐based data analysis. This study will show the application as well as the pros and cons of these types of data analysis for very complex matrices like cigarette particulate matter. In addition, new aspects about the recently discovered puff‐dependent behaviour of compounds in cigarette smoke will be presented. Automated peak‐based compound classification including mass spectrometric pattern recognition is used for the classification of tobacco particulate matter samples and the puff‐dependent investigation of different compound classes. This compound group specific analysis is further reinforced by applying an even more comprehensive pixel‐based analysis. This kind of analysis is used to generate fingerprints of different types of cigarettes. The combination of fast feature reduction methods like analysis of variance (ANOVA) and t‐test with multivariate feature transformation methods like partial least squares discriminate analysis (PLSDA) for feature selection provides a powerful tool for a detailed inspection of different types of cigarettes.
The link between board composition and board objectives: an empirical analysis on Flemish non‐profit schools
Authors: Du Bois Cind , Caers Ralf , Jegers Marc , De Cooman Rein , De Gieter Sara , Pepermans Roland 
Published: October 2008

AbstractFlemish non‐profit schools have no legally imposed composition rules with respect to their board of directors. Hence, large variation exists in their size and composition. We argue that these differences in board composition can result in different policies followed by the board. To empirically test this hypothesis we question the board's chairpersons of Flemish non‐profit schools about the objectives set forward by the board. Ordered probit regressions on the importance attached to different educational objectives provide support for our hypothesis and thus alert policy makers to account for the linkages between objectives and board characteristics when formulating legislation with respect to school board composition. Copyright © 2008 John Wiley & Sons, Ltd.
Multi‐unit pricing
Authors: McCannon Bryan C. 
Published: October 2008

AbstractA price takes the form of a cost for either one unit (single‐unit pricing) or multiple units (multi‐unit pricing). I consider a monopolist selling units of a good to a population of homogeneous consumers to explain why one is preferred to the other. A mental cost arises if the division problem a multi‐unit price causes is done. If marginal utility remains high multiple units are desired. Multi‐unit pricing is preferred since it creates a cost if fewer units are purchased. If utility exhibits strong diminishing returns single‐unit pricing is used to avoid the calculation. Copyright © 2008 John Wiley & Sons, Ltd.
Matrix proteins of basement membrane of intrahepatic bile ducts are degraded in congenital hepatic fibrosis and Caroli's disease
Authors: Yasoshima Mitsue , Sato Yasunori , Furubo Shinichi , Kizawa Kazuo , Sanzen Takahiro , Ozaki Satoru , Harada Kenichi , Nakanuma Yasuni 
Published: October 2008

AbstractCongenital hepatic fibrosis (CHF) and Caroli's disease are though to result from ductal plate malformation, and the basal laminar components play important roles in biliary differentiation during development. To clarify the involvement of basal laminar components in the ductal plate malformation, this study examined the immunohistochemical expression of laminin and type IV collagen in the livers of CHF and Caroli's disease. Using the polycystic kidney (PCK) rat, an animal model of Caroli's disease with CHF, in vivo and in vitro experiments were also performed. Immunostaining showed that basement membrane expression of laminin and type IV collagen around intrahepatic bile ducts was degraded in CHF, Caroli's disease, and the PCK rats. The degradation of laminin and type IV collagen around bile ducts was also observed in foci of cholangiocarcinoma in situ of Caroli's disease. In vitro, PCK cholangiocytes were found to overexpress plasminogen and a serine proteinase, the tissue‐type plasminogen activator (tPA). When PCK cholangiocytes were cultured in Matrigel™, the amounts of laminin and collagen in the gel were significantly reduced, and addition of α2‐antiplasmin in the culture medium inhibited the degradation of laminin and collagen in Matrigel™. These results suggest that biliary overexpression of plasminogen and tPA leads to the generation of excessive amounts of plasmin, and subsequent plasmin‐dependent lysis of the extracellular matrix molecules may contribute to the biliary dysgenesis in CHF and Caroli's disease, including progressive cystic dilatation of the intrahepatic bile ducts in Caroli's disease. In addition, it is suggested that once cholangiocarcinoma in situ develops in the biliary epithelium of CHF and Caroli's disease, it tends to transform into invasive carcinoma, due to instability of the basement membrane of the bile ducts. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Prospective experience with integrated prenatal screening and first trimester combined screening for trisomy 21 in a large Canadian urban center
Authors: Okun Nanette , Summers Anne M. , Hoffman Barry , Huang Tianhua , Winsor Elizabeth , Chitayat David , Staines A. , Johnson Jo‐Ann 
Published: October 2008

AbstractObjectivesTo evaluate the performance of integrated prenatal screening (IPS) and first trimester combined screening (FTS) for trisomy 21 in a large Canadian urban center.MethodProspective data collection on women having FTS at one center from 1 November 2003 to 31 December 2005, or IPS at another from 1 January 2003 to 31 December 2005. A positive screen was defined as adjusted risk for trisomy 21 ≥ 1/200 at term or nuchal translucency ≥ 3.5 mm.Results32 227 and 14 487 women were screened in the IPS and FTS programs, respectively. Detection rates (DRs) and positive rates (PRs) for trisomy 21 were 88.4% (95% CI: 81.6–91.5) and 3.3% (95% CI: 3.1–3.5) for IPS, and 83.9% (95% CI: 74.7–93.0) and 4.0% (95% CI: 3.7–4.3) for FTS. DR adjusted for viability bias was 85.2% for IPS and 78.6% for FTS. Applying both the screens to the 78 134 women who submitted prenatal screens in Ontario in 2005, thereby eliminating the effect of differences in the distribution of maternal age between screens, gave a DR (corrected for viability bias) and PR of 81 and 3.1% for IPS, and 76 and 3.4% for FTS.ConclusionsBoth IPS and FTS perform well and are feasible in a practical clinical setting. Copyright © 2008 John Wiley & Sons, Ltd.
Diamniotic twin pregnancies with a single placental mass; prediction of chorionicity at 11 to 14 weeks of gestation
Authors: Moon Min Hoan , Park Su Yeon , Song Mi Jin , Yang Jae Hyug , Kim Moon Young , Hong Sung Ran , Park Seong Ho 
Published: October 2008

AbstractObjectiveTo assess the accuracy of transvaginal ultrasound (US) in the prediction of the chorionicity of diamniotic twin pregnancies with a single placental mass at 11 to 14 weeks of gestation.MethodFrom June 2006 to April 2007, we determined chorionicities by depiction of the amnion and chorion at the membrane‐to‐placental interface using transvaginal US. Pregnancies were classified as monochorionic when two layers of the amnion were identified as dichorionic when either one layer of the chorion and two layers of the amnion or one layer of the chorion and one layer of the amnion were seen.ResultsIn 65 out of 70 (92.9%) diamniotic twin pregnancies with a single placental mass, we were able to determine the chorionicity by depiction of the amnion and chorion at the membrane‐to‐placental interface using transvaginal US. The predictive accuracy was 100% (95% confidence interval: 92–100%) for 52 twin pregnancies considered to be dichorionic by transvaginal US and 100% (95% CI: 73–100%) for 13 twin pregnancies considered to be monochorionic.ConclusionThe chorionicity of diamniotic twin pregnancies with a single placental mass can be reliably predicted by transvaginal US depiction of the amnion and chorion at 11 to 14 weeks of gestation. Copyright © 2008 John Wiley & Sons, Ltd.
Vildagliptin: alternative add‐on therapy for oral glycaemic control
Authors: Chaplin Steve , Campbell Ian 
Published: October 2008

AbstractVildagliptin, an oral DPP‐4 inhibitor, is licensed as an add‐on therapy when adequate glycaemic control has not been achieved with metformin, a sulphonylurea or a glitazone. In our New products review Steve Chaplin presents the clinical data relating to its efficacy and adverse effects, and Professor Ian Campbell comments on its place in type 2 diabetes therapy. Copyright © 2008 Wiley Interface Ltd
Electron spin precession observed in bulk CdTe at room temperature
Authors: Ito Tetsu , Shichi Wataru , Okami Yoshitaka , Ichida Masao , Gotoh Hideki , Kamada Hidehiko , Ando Hiroaki 
Published: October 2008

AbstractWe report on spin precession observed in CdTe and GaAs bulks at room temperature by means of time‐resolved Kerr rotation measurements under a high magnetic field. Electron g‐factor in CdTe obtained from the spin precession measurements was significantly different from that in GaAs having similar band gap because of stronger spin‐orbital interaction in CdTe. Theoretical analysis on temperature dependence of the g‐factor was also conducted, based on 3‐band k·p perturbation theory, to estimate the effects of remote bands other than the 3 bands. The dependence of the electron g‐factor on temperature was numerically reproduced in low temperature region by considering thermal distribution of electrons. The effects of the remote bands are discussed in relation to the discrepancy between experiments and theoretical analysis in higher temperature region. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Triplet‐triplet absorption transitions in self‐trapped exciton and F2 centers in alkali halides
Authors: Lisitsyna Liudmila 
Published: October 2008

AbstractThe results of comparative analysis of triplet‐triplet absorption spectra, optical binding energy, the lifetime of self‐trapped excitons (STE) and F2 centers in KCl, KBr, KI and NaCl are presented. The coincidence of triplet–triplet absorption spectra of F2 centers and of STE in the spectral interval of 1‐3 eV in one and the same crystal was discovered. It is true for each crystal under consideration in spite of that the calculated value of axial shift of STE Vk core varies in a wide range of 0.9–4.3 Å. It was revealed that the value of optical binding energy of the both STE and F2 center coincides in one and the same crystal. Consequently the depth of the well in which the electron of STE is trapped seems to be defined by the lattice energy only. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Time‐resolved photoinduced Kerr rotation in semiconductor microcavity
Authors: Mitsumori Y. , Kato N. , Kosaka H. , Edamatsu K. , Yamamoto N. , Akahane K. 
Published: October 2008

AbstractWe studied photoinduced Kerr effect in cavity polaritons in a semiconductor microcavity by carefully measuring the time‐resolved Kerr rotation and ellipticity spectra. The Kerr rotation angle of the microcavity polaritons is a hundred times larger than a conventional single quantum well. A spectral shape analysis of the observed spectra suggests that the photoindeced Kerr effect mainly results from a line broadening of the polarions due to spin‐polarized polariton‐polariton scattering. Enhancement in oscillator strength also contributes to the large rotation angle. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Asymmetric temporal profile of optical Kerr signal from GaAs/AlAs multilayer with λ/2 phase shift layer
Authors: Morita Ken , Kanbara Toshiyuki , Shinsuke Yano , Kitada Takahiro , Isu Toshiro 
Published: October 2008

AbstractOptical Kerr response for a short‐input‐pulse of a GaAs/AlAs multilayer cavity which has a narrow cavity mode width was measured by an optical pump and probe technique. We observed a strong asymmetric temporal profile of the optical Kerr signal in the vicinity of Δt = 0. The initial rising time of the signal was 1.0 ps for Δt < 0, while the decay time was 0.25 ps for Δt > 0. The asymmetric profile of the Kerr signal was analyzed with the pulse shapes of the pump and probe pulses in the cavity. We found that the decay of the Kerr signal for Δt > 0 was faster than that of the profile explained by the pump and probe pulses. This suggests that the strong asymmetric profile of the Kerr signal was occurred by the strong phase shift due to the higher order term of the susceptibility. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Literature overview: Emerging organic contaminants in water and their remediation
Authors: Husain Saleha 
Published: October 2008

AbstractEmerging organic contaminants (EOCs) are widespread in the environment, and concentrations above the acceptable limits are being detected due to improved detection methods, technologies, and regulations for their monitoring. Increasing use of new consumer, pharmaceutical, and scientific products has introduced EOCs, such as nanomaterials and siloxanes, into the environment. The releases of EOCs into the environment can lead to surface‐water, soil, and groundwater contamination. The presence of pharmaceuticals and their enantiomers can lead to resistant algal strains and, thus, more persistent algal toxins. This review discusses some of the prominent EOCs and the methods for their remediation. This is useful for assessing current remediation technologies and for developing new technologies to treat EOCs in water. © 2008 Wiley Periodicals, Inc.
Integral moments of automorphic L-functions
Authors: Diaconu Adrian , Garrett Paul 
Published: October 2008

AbstractWe obtain second integral moments of automorphic L-functions on adele groups GL2 over arbitrary number fields, by a spectral decomposition using the structure and representation theory of adele groups GL1 and GL2. This requires reformulation of the notion of Poincaré series, replacing the collection of classical Poincaré series over GL2(ℚ) or GL2(ℚ(i)) with a single, coherent, global object that makes sense over a number field. This is the first expression of integral moments in adele-group terms, distinguishing global and local issues, and allowing uniform application to number fields. When specialized to the field of rational numbers ℚ, we recover the classical results on moments.
A new two-columns description for convective transport in stars
Authors: Stökl Alexander 
Published: October 2008

AbstractAssuming that the largest convective patterns generate the majority of convective transport, we devise a numerical scheme simplifying the convective velocity field using two parallel radial columns to represent up- and downstream flows. Horizontal exchange is described by fluid flow and radiation over the interface between those two columns. The main parameters of this convective description have a straightforward geometrical meaning, namely the diameter of the columns (representing the size of the convective cells) and the ratio of cross section between up- and downdrafts. For this geometrical setup, the equations of radiation hydrodynamics are solved time-dependently using an implicit scheme which has the advantage of being devoid of any time step limits. In order to demonstrate our approach, we present comparisons with detailed 2D hydrodynamics computations for the example of convection zones in Cepheids.
Thermohaline mixing in low-mass giants
Authors: Cantiello M. , Langer N. 
Published: October 2008

AbstractThermohaline mixing has recently been proposed to occur in low mass red giants, with large consequences for the chemical yields of low mass stars. We investigate the role of thermohaline mixing during the evolution of stars between 1 M⊙ and 3 M⊙, in comparison to other mixing processes acting in these stars. We confirm that thermohaline mixing has the potential to destroy most of the 3He which is produced earlier on the main sequence during the red giant stage. In our models we find that this process is working only in stars with initial mass M ≲ 1.5 M⊙. Moreover, we report that thermohaline mixing can be present during core helium burning and beyond in stars which still have a 3He reservoir. While rotational and magnetic mixing is negligible compared to the thermohaline mixing in the relevant layers, the interaction of thermohaline motions with differential rotation and magnetic fields may be essential to establish the time scale of thermohaline mixing in red giants.
Asteroseismic constraints on the OPAL opacity interpolation
Authors: Yang W. M. , Li M. 
Published: October 2008

AbstractThere is a difference of a few Kelvins in the effective temperature between a model used only two-point interpolation of opacity and a model used piecewise linear interpolation of opacity. However the frequency difference between the models is of the order of several microHertz at a certain stage, which is almost 10 times worse than the observational precision of p-modes of solar-like stars. Therefore, the two-point interpolation of opacity is unsuitable in modelling of solar-like stars with element diffusion.
Radio Star Candidates from FIRST and 2MASS Databases
Authors: Zhang Yanxia , Zhao Yongheng 
Published: October 2008

AbstractWe positionally cross-identified FIRST (the Faint Images of the Radio Sky at Twenty centimeters) catalogue with 2MASS (the Two Micron All Sky Survey) pointed-source database and collected the data from radio band and near infrared band. Then the data were cross-matched with the Véron-Cetty & Véron 2006 catalog and the Tycho-2 catalog, respectively. Therefore the known samples of quasars and stars are obtained. We applied principal component analysis (PCA) on the known sample. The overall sample may be projected in the principal component space. From the space, we can easily locate the area that radio stars occupy, and select out radio star candidates. With the follow-up observation of these candidates, the properties of radio stars may be studied.
Hydrodynamic simulations of the core helium flash
Authors: Mocák Miroslav , Müller Ewald , Weiss Achim , Kifonidis Konstantinos 
Published: October 2008

AbstractWe desribe and discuss hydrodynamic simulations of the core helium flash using an initial model of a 1.25 M⊙ star with a metallicity of 0.02 near at its peak. Past research concerned with the dynamics of the core helium flash is inconclusive. Its results range from a confirmation of the standard picture, where the star remains in hydrostatic equilibrium during the flash (Deupree 1996), to a disruption or a significant mass loss of the star (Edwards 1969; Cole & Deupree 1980). However, the most recent multidimensional hydrodynamic study (Dearborn et al. 2006) suggests a quiescent behavior of the core helium flash and seems to rule out an explosive scenario. Here we present partial results of a new comprehensive study of the core helium flash, which seem to confirm this qualitative behavior and give a better insight into operation of the convection zone powered by helium burning during the flash. The hydrodynamic evolution is followed on a computational grid in spherical coordinates using our new version of the multi-dimensional hydrodynamic code HERAKLES, which is based on a direct Eulerian implementation of the piecewise parabolic method.
Solar-like oscillations in red giant ϵ Ophiuchi
Authors: Bi S. L. , Gai N. 
Published: October 2008

AbstractAsteroseismology is a powerful tool to help determining the internal structure of the stars. Solar-like oscillations have been discovered in the G9.5 red giant ϵ Ophiuchi, and it opened up a new part of the Hertzsprung-Russell diagram to be explored with asteroseismic techniques. We present the detailed study of the properties of ϵ Oph including convective overshooting and extra-mixing.
Massive star evolution: from the early to the present day Universe
Authors: Meynet Georges , Ekström Sylvia , Georgy Cyril , Maeder André , Hirschi Raphael 
Published: October 2008

AbstractMass loss and axial rotation are playing key roles in shaping the evolution of massive stars. They affect the tracks in the HR diagram, the lifetimes, the surface abundances, the hardness of the radiation field, the chemical yields, the presupernova status, the nature of the remnant, the mechanical energy released in the interstellar medium, etc. . . In this paper, after recalling a few characteristics of mass loss and rotation, we review the effects of these two processes at different metallicities. Rotation probably has its most important effects at low metallicities, while mass loss and rotation deeply affect the evolution of massive stars at solar and higher than solar metallicities.
The single degenerate channel for the progenitors of Type Ia supernovae
Authors: Meng Xiangcun , Chen Xuefei , Han Zhanwen 
Published: October 2008

AbstractWe have carried out a detailed study of the single-degenerate channel for the progenitors of type Ia supernovae (SNe Ia). In the model, a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from an unevolved or a slightly evolved non-degenerate companion to increase its mass to Chandrasekhar mass limit. Incorporating the prescription of Hachisuet al. (1999a) for the accretion efficiency into Eggleton's stellar evolution code and assuming that the prescription is valid for all metallicities, we performed binary stellar evolution calculations for more than 25,000 close WD binary systems with various metallicities. The initial parameter spaces for SNe Ia are presented in an orbital period-secondary mass (logPi,M2i) plane for eachZ.Adopting the results above, we studied the birth rate of SNe Ia for variousZvia binary population synthesis. From the study, we see that for a highZ, SNe Ia occur systemically earlier and the peak value of the birth rate is larger if a single starburst is assumed. The Galactic birth rate from the channel is lower than (but comparable to) that inferred from observations.We also showed the distributions of the parameters of the binary systems at the moment of supernova explosion and the distributions of the properties of companions after supernova explosion. The former provides physics input to simulate the interaction between supernova ejecta and its companion, and the latter is helpful for searching the companions in supernova remnants.
Modelling the evolution and nucleosynthesis of carbon-enhanced metal-poor stars
Authors: Pols O. R. , Izzard R. G. , Lugaro M. , de Mink S. E. 
Published: October 2008

AbstractWe present the results of binary population simulations of carbon-enhanced metal-poor (CEMP) stars. We show that nitrogen and fluorine are useful tracers of the origin of CEMP stars, and conclude that the observed paucity of very nitrogen-rich stars puts strong constraints on possible modifications of the initial mass function at low metallicity. The large number fraction of CEMP stars may instead require much more efficient dredge-up from low-metallicity asymptotic giant branch stars.