bluuebunny/crossref_metadata_2025_split huggingface dataset:
Infrared Spectra of Protonated Uracil, Thymine and Cytosine
Authors: Salpin Jean‐Yves , Guillaumont Sébastien , Tortajada Jeanine , MacAleese Luke , Lemaire Joël , Maitre Philippe 
Published: October 2007

AbstractThe gas‐phase structures of protonated uracil, thymine, and cytosine are probed by using mid‐infrared multiple‐photon dissociation (IRMPD) spectroscopy performed at the Free Electron Laser facility of the Centre Laser Infrarouge d′Orsay (CLIO), France. Experimental infrared (IR) spectra are recorded for ions that were generated by electrospray ionization, isolated, and then irradiated in a quadrupole ion trap; the results are compared to the calculated infrared absorption spectra of the different low‐lying isomers (computed at the B3LYP/6‐31++G(d,p) level). For each protonated base, the global energy minimum corresponds to an enolic tautomer, whose infrared absorption spectrum matched very well with the experimental IRMPD spectrum, with the exception of a very weak IRMPD signal observed at about 1800 cm−1 in the case of the three protonated bases. This signal is likely to be the signature of the second‐energy‐lying oxo tautomer. We thus conclude that within our experimental conditions, two tautomeric ions are formed which coexist in the quadrupole ion trap.
IR and NMR Properties of Ionic Liquids: Do They Tell Us the Same Thing?
Authors: Wulf Alexander , Fumino Koichi , Michalik Dirk , Ludwig Ralf 
Published: October 2007

AbstractWe used a combination of theoretical and experimental methods to derive the spectroscopic properties of imidazolium‐based ionic liquids. Vibrational frequencies, NMR chemical shifts, and quadrupole coupling constants react in comparable manner to changes in the chemical environment. This suggests that both the IR and the NMR spectroscopic properties reflect a similar type of electronic perturbation caused by hydrogen bonding. These relationships of the spectroscopic properties provide detailed information about structural complexes and may thus serve as good indicators of ion‐pair formation. They also help to decide which spectroscopic tool is the most sensitive for investigating molecular interactions. The measurement of only one spectroscopic property allows the prediction of other properties that cannot be so easily measured. In some cases, this is the only way to obtain reliable coupling constants for deriving molecular correlation times from macroscopic NMR relaxation times, thus opening a new path for studying structure–dynamics relations in ionic liquids.
The sources and manifestations of stress amongst school‐aged dyslexics, compared with sibling controls
Authors: Alexander‐Passe Neil 
Published: October 2007

AbstractAll school children experience stress at some point in their school careers. This study investigates whether dyslexic children, by way of their educational and social difficulties, experience higher levels of stress at school. The School Situation Survey was used to investigate both the sources and manifestations of stress amongst dyslexic children and non‐dyslexic sibling controls. Samples were broken down by gender, age and the size of families. Results suggest significant differences between the groups, with dyslexics in academic years 3–5 experiencing the highest stress levels, specifically in interactions with teachers, worries over academic examinations (SATs) and performance testing, causing emotional (fear, shyness and loneliness) and physiological (nausea, tremors or rapid heart beat) manifestations. Results also suggest that dyslexics in larger families (3–4 sibling families) experience greater stress in interactions with their peers, than those in smaller families (two sibling families)—possibly from unfair sibling comparison. Copyright © 2007 John Wiley & Sons, Ltd.
Oxoethoxide Chlorides – Representatives of Oligonuclear Alkoxide Complexes of Gallium: Penta‐ and Dodecanuclear Molecules
Authors: Suslova Evgeniya V. , Kessler Vadim G. , Gohil Suresh , Turova Nataliya Ya. 
Published: October 2007

AbstractMetathesis of solid GaCl3 with NaOEt/EtOH (1:3) provided, after separation of the NaCl precipitate, a solution containing oxoalkoxide chloride complexes of gallium. Residues from evacuation of the latter were redissolved in either toluene/MeCN (solution 1) or toluene/pyridine (solution 2). Storage of the first solution provided crystals of Ga5(μ5‐O)(μ‐OEt)8Cl5 (1), and of the second solution – [Ga12(μ4‐O)2(μ3‐O)5(μ‐OEt)10Cl12Py4]Py (2), both at room temperature and in relatively high yields. Compound 1 crystallizes as a vertically contracted tetragonal pyramid with the μ5‐O ligand situated in the center of the equatorial plane defined by four trigonal bipyramidal coordinated gallium atoms. The axial Ga atom has octahedral coordination. All eight edges of the pyramid are capped by μ‐OEt groups, and all the chloride ligands are situated in terminal positions. Crystals of [Ga12(μ4‐O)2(μ3‐O)5(μ‐OEt)10Cl12Py4]Py (2) contain two [Ga5(μ4‐O)(μ3‐O)2(μ‐OEt)5Cl5Py] fragments connected through a cyclic [Ga4(μ3‐O)5Cl2Py2] unit with a μ3‐O ligand in its center. Of the metal atoms, three possess tetrahedral, seven trigonal bipyramidal, and two octahedral coordination. The mass spectrum of 1 contains penta‐ and tetranuclear fragments. The spectrum of 2 contains heptameric fragments in addition to the pentanuclear fragments that are analogous to those in the spectrum of 1. The factors leading to formation of polymeric M(OR)n and related oligonuclear oxocomplexes are discussed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis of Bis(catechol) Ligands Derived from Tröger's Base and Their Dinuclear Triple‐Stranded Complexes with Titanium(IV) Ions
Authors: Kiehne Ulf , Lützen Arne 
Published: October 2007

AbstractBis(catechol) ligands derived from 2,8‐disubstituted analogues of Tröger's base and monofunctionalized MOM‐protected or unprotected catechols bearing both rigid and flexible spacers were synthesized, which gave rise to dissymmetric oxygen donor ligands whose geometry is defined by the V‐shaped and rigid structure of the core of Tröger's base. These racemic ligands undergo self‐assembly to dinuclear triple‐stranded helicates upon coordination to titanium(IV) ions as was proven by NMR spectroscopy and ESI‐MS experiments; however, these processes are not diastereoselective.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Intra‐group interaction and the development of norms which promote inter‐group hostility
Authors: Smith Laura G. E. , Postmes Tom 
Published: October 2007

AbstractResearch suggests there is more inter‐group discrimination when rewards rather than punishments are distributed between groups (the positive‐negative asymmetry effect). This study investigated whether intra‐group interaction and the obstruction of in‐group advancement moderate this finding. Participants were twice asked to divide monetary resources—individually (pre‐consensus) and in interactive groups (consensus). Results confirmed that there was more discrimination when rewards were allocated. Although this replicates the PNAE overall, there were two moderators. First, there was no asymmetry when the out‐group obstructed in‐group advancement: obstruction was sufficient to legitimise punishment. Second, after group interaction the PNAE reversed so that there was more discrimination when punishments were administered. The severity of discrimination was contingent upon group norms that endorsed inter‐group hostility. It is argued that norms changed as a function of group interaction, and so did patterns of discrimination. The results suggest that the intra‐and inter‐group context combined to cause in‐group favouritism to slide towards inter‐group hostility. Copyright © 2007 John Wiley & Sons, Ltd.
The glycerin glut: Options for the value‐added conversion of crude glycerol resulting from biodiesel production
Authors: Johnson Duane T. , Taconi Katherine A. 
Published: October 2007

AbstractDramatic increases in the price of crude oil, and consequently, transportation fuels, coupled with increased environmental concerns have resulted in rapid growth in biodiesel production, both in the United States and worldwide. As biodiesel production increases, so does production of the primary coproduct, glycerol. Since the existing glycerol supply and demand market was tight, recent increases in glycerol production from biodiesel refining has created a glut in the glycerol market. As a result, the price of glycerol has fallen significantly and biodiesel refiners are faced with limited options for managing the glycerol by‐product, which in the biodiesel industry, has essentially become a waste stream. This article is a review of promising options for both the catalytic and biological conversion of glycerol into various value‐added products, many of which are bio‐based alternatives to petroleum‐derived chemicals. © 2007 American Institute of Chemical Engineers Environ Prog, 26: 338–348, 2007
A catchment‐scale assessment of anabranching in the 143 000 km2 Fitzroy River catchment, north‐eastern Australia
Authors: Amos Kathryn J. , Croke Jacky C. , Hughes Andrew O. , Chapman Joanne , Takken Ingrid , Lymburner Leo 
Published: October 2007

AbstractThis paper presents a catchment‐scale investigation of anabranching in the moderately large 143 000 km2 Fitzroy River catchment in north‐eastern Australia. The primary aim is to determine whether mapped and remotely sensed data can provide useful information about the characteristics of anabranching in a catchment of this scale. Anabranching comprises 6% of the total channel network by length, and 24% of higher‐order channels (those with catchment areas over 100 km2). Three anabranching planform morphologies are described, which occur in geographically distinct regions, and add to previous descriptions of anabranching rivers. Sinuosity and link length are calculated for all channels of the mapped channel network (a link is a stretch of river between two stream junctions). Slope, mean floodplain width, mean annual rainfall and underlying and catchment geology parameters are calculated for links of a stream network derived from a digital elevation model (DEM), in which each link has either a single channel or anabranching morphology. Anabranching and single channel links do not occupy different ranges of attribute values, and a logistic regression analysis was unable to predict anabranching. However, slope, catchment area, mean floodplain width, length and sinuosity parameters all have significantly different means when comparing single channel with anabranching links, although it is shown that the difference in mean floodplain widths is the result of its correlation with catchment area. Anabranching channels have a tendency towards shorter link lengths, lower sinuosities and lower valley slopes and occur at larger catchment areas than single channels. These differences are discussed in the context of published hypotheses regarding the cause of anabranching. However, the spatial resolution and precision of our data limit our ability to investigate controls on anabranching, which will require detailed measurement of variables at a reach scale. Copyright © 2007 John Wiley & Sons, Ltd.
Daytime pharmacodynamic and pharmacokinetic evaluation of low‐dose sublingual transmucosal zolpidem hemitartrate
Authors: Roth Thomas , Mayleben David , Corser Bruce C. , Singh Nikhilesh N. 
Published: October 2007

AbstractObjectivesBuffered low‐dose sublingual transmucosal zolpidem lozenge hemitartrate (ST zolpidem) is being developed for the treatment of middle‐of‐the‐night insomnia. The objective of this double‐blind placebo‐controlled cross‐over study (n = 24) was to evaluate the pharmacokinetics (PK) and daytime‐sedative profile of 1.0, 1.75, and 3.5 mg dose of the formulation.MethodsDaytime sedation was measured pre‐dose and up to 5 h post‐dose objectively by the Digit Symbol Substitution Test (DSST) and subjectively using the Visual Analog Scale (VAS). Blood samples for PK assessment was collected pre‐dose and up to 12 h post‐dose.ResultsThe 1.75 and 3.5 mg, but not the 1 mg, ST zolpidem produced significant sedation versus placebo within 20 min of dosing which lasted for up to 3 h. Zolpidem from the formulation was rapidly absorbed and reached maximum plasma concentrations within 38 min of dosing, however the half‐life was independent of the dose and side effects were consistent with the known pharmacology of the drug.ConclusionsST zolpidem produced rapid, short duration of sedation and the effect was consistent with its PK profile. This novel low‐dose formulation of zolpidem may provide clinicians and patients with a prn option for the management of sleep maintenance insomnia. Copyright © 2007 John Wiley & Sons, Ltd.
A fuzzy dynamic wave routing model
Authors: Gopakumar R. , Mujumdar P. P. 
Published: October 2007

AbstractIn this paper a fuzzy dynamic wave routing model (FDWRM) for unsteady flow simulation in open channels is presented. The continuity equation of the dynamic wave routing model is preserved in its original form while the momentum equation is replaced by a fuzzy rule based model which is developed on the principle that during unsteady flow the disturbances in the form of discontinuities in the gradient of the physical parameters will propagate along the characteristics with a velocity equal to that of velocity of the shallow water wave. The model gets rid off the assumptions associated with the momentum equation by replacing it with the fuzzy rule based model. It overcomes the necessity of calculating friction slope (Sf) in flow routing and hence the associated uncertainties are eliminated. The robustness of the fuzzy rule based model enables the FDWRM to march the solution even in regions where the aforementioned assumptions are violated. Also the model can be used for flow routing in curved channels. When the model is applied to hypothetical flood routing problems in a river it is observed that the results are comparable to those of an implicit numerical model (INM) which solves the dynamic wave equations using an implicit numerical scheme. The model is also applied to a real case of flow routing in a field canal. The results match well with the measured data and the model performs better than the INM. Copyright © 2007 John Wiley & Sons, Ltd.
Pedotransfer functions estimating soil hydraulic properties using different soil parameters
Authors: Børgesen Christen D. , Iversen Bo V. , Jacobsen Ole H. , Schaap Marcel G. 
Published: October 2007

AbstractEstimates of soil hydraulic properties using pedotransfer functions (PTF) are useful in many studies such as hydrochemical modelling and soil mapping. The objective of this study was to calibrate and test parametric PTFs that predict soil water retention and unsaturated hydraulic conductivity parameters. The PTFs are based on neural networks and the Bootstrap method using different sets of predictors and predict the van Genuchten/Mualem parameters. A Danish soil data set (152 horizons) dominated by sandy and sandy loamy soils was used in the development of PTFs to predict the Mualem hydraulic conductivity parameters. A larger data set (1618 horizons) with a broader textural range was used in the development of PTFs to predict the van Genuchten parameters. The PTFs using either three or seven textural classes combined with soil organic mater and bulk density gave the most reliable predictions of the hydraulic properties of the studied soils. We found that introducing measured water content as a predictor generally gave lower errors for water retention predictions and higher errors for conductivity predictions. The best of the developed PTFs for predicting hydraulic conductivity was tested against PTFs from the literature using a subdata set of the data used in the calibration. The test showed that the developed PTFs gave better predictions (lower errors) than the PTFs from the literature. This is not surprising since the developed PTFs are based mainly on hydraulic conductivity data near saturation and sandier soils than the PTFs from the literature. Copyright © 2007 John Wiley & Sons, Ltd.
Continuous spatially distributed simulation of surface and subsurface hydrological processes in a small semiarid catchment
Authors: Maneta Marco , Schnabel Susanne , Jetten Victor 
Published: October 2007

AbstractModelling the hydrologic processes of semiarid basins is specially challenging due to the specific characteristics of this type of environment. The discontinuity of the processes both in space and in time produces a highly complicated rainfall–runoff relationship. Runoff production and reinfiltration areas produce a discontinuous spatial pattern of runoff; channel flow is ephemeral and restricted to the wet season of the year or to heavy rainfalls, and many local saturated layers of soil separated by unsaturated areas can occur. The hydrological connection of the different parts of the basin produces a nonlinear and complex hydrologic behaviour because different response mechanisms of the basin are triggered as the hydrological connectivity increases. Similarly, as connectivity decreases, so does the information arriving at the monitored state variables used to calibrate the model and to understand the system. This paper describes the application of a distributed hydrologic model to describe the hydrologic behaviour of a small semiarid basin including surface and subsurface processes. The model is parameterized and calibrated to simulate a period of 71 days covering the transition of the basin from a dry to a wet state, during which most of the hydrologic processes of the basin are activated. The calibration strategy used different sources and types of information on the state of the basin and an efficient gradient based search algorithm to find the optimal values of the most sensitive parameters. The modelled hydrograph and the modelled internal description of the basin were analysed in the light of its known behaviour and the existing knowledge of semiarid hydrology reported in the literature. The results indicate that while the integrated behaviour of the basin represented by the output hydrograph can be well reproduced, the subsurface processes and the internal dynamics of the basin are less accurately simulated, mainly due to the lack of information on the geometry of the subsurface domain (soil depths and bedrock topography) and on the spatial distribution of the parameters. Copyright © 2007 John Wiley & Sons, Ltd.
Effects of reduced land cover detail on hydrological model response
Authors: Armstrong Robert N. , Martz Lawrence W. 
Published: October 2007

AbstractProblems related to scale continue to be at the forefront of research in hydrology. Past research into issues of scale has focused mainly on digital elevation model grid size, the appropriate number and size of sub‐areas for subdividing a watershed, parameter transferability between watersheds and appropriate scales for linking hydrological and general circulation models. Much less attention has been given to the effects of scale on the representation of land cover and hydrological model response. Recent studies with respect to changes in land cover and hydrologic response have tended to focus on the issue of land cover maturity and the conversion of land through agricultural and forestry practices. The focus of this study is to examine the impact of the level of detail at which land cover is represented in modelling the hydrological response of Wolf Creek Basin in northwest Canada. A grid‐based land cover map with a spatial resolution of 30 m is coarsened or smoothed using several common grid‐based methods of aggregating categorical data, including: pixel thinning, modal smoothing and modal aggregation. A majority rule method based on polygons is also applied to the 30 m base cover. The SLURP hydrologic model is calibrated for the base cover and used as a reference for comparing simulations for the coarsened or ‘generalized’ land cover maps. Results of the simulations are compared to examine the sensitivity of hydrologic response to generalized land cover information. Comparisons of the SLURP model runs for Wolf Creek suggest that reducing the level of detail of land cover information generally has a limited effect on hydrologic response at the outlet. However, results for averages of water balance components across the basin suggest that the local variability of hydrologic response is affected in general. Copyright © 2007 John Wiley & Sons, Ltd.
Control of osteopontin signaling and function by post‐translational phosphorylation and protein folding
Authors: Kazanecki Christian C. , Uzwiak Dana J. , Denhardt David T. 
Published: October 2007

AbstractOsteopontin (OPN) plays roles in a variety of cellular processes from bone resorption and extracellular matrix (ECM) remodeling to immune cell activation and inhibition of apoptosis. Because it binds receptors (integrins, CD44 variants) typically engaged by ECM molecules, OPN acts as a “soluble” ECM molecule. A persistent theme throughout the characterization of how OPN functions has been the importance of phosphorylation. The source of the OPN used in specific experiments and the location of modified sites is an increasingly important consideration for OPN research. We review briefly some of the ways OPN impacts on the biology of mammalian systems with an emphasis on the importance of serine phosphorylation in modulating its signaling ability. We describe experiments that support the hypothesis that differences in the post‐translational phosphorylation of OPN expressed by different cell types regulate how it impacts on target cells. Analyses of OPN's potential secondary structure reveal a possible beta‐sheet conformation that offers an interpretation of certain experimental observations, specifically the effect of thrombin cleavage; it is consistent with an interaction between the C‐terminal region of the protein and the central integrin‐binding RGD sequence. J. Cell. Biochem. 102: 912–924, 2007. © 2007 Wiley‐Liss, Inc.
New Tabu Search based global optimization methods outline of algorithms and study of efficiency
Authors: Stepanenko Svetlana , Engels Bernd 
Published: October 2007

AbstractThe study presents two new nonlinear global optimization routines; the Gradient Only Tabu Search (GOTS) and the Tabu Search with Powell's Algorithm (TSPA). They are based on the Tabu‐Search strategy, which tries to determine the global minimum of a function by the steepest descent–mildest ascent strategy. The new algorithms are explained and their efficiency is compared with other approaches by determining the global minima of various well‐known test functions with varying dimensionality. These tests show that for most tests the GOTS possesses a much faster convergence than global optimizer taken from the literature. The efficiency of the TSPA compares to the efficiency of genetic algorithms. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Carbon‐14 labeling of Saxagliptin (BMS‐477118)
Authors: Cao Kai , Bonacorsi Samuel J. , Balasubramanian Balu , Hanson Ronald L. , Manchand Percy , Godfrey Jollie D. , Fox Rita , Christopher Lisa J. , Su Hong , Iyer Ramaswamy 
Published: October 2007

AbstractAn efficient synthesis of carbon‐14‐labeled Saxagliptin (BMS‐477118) is described. Initial synthesis of the key radiolabeled intermediate (S)‐N‐Boc‐2‐(3′‐hydroxyadamantyl)glycine 2a utilized adamantanemethanol in a 10‐step sequence. To shorten the sequence, 1‐adamantylzinc bromide was reacted with ethyl [1, 2‐14C]oxalyl chloride catalyzed by [1,1′‐bis(diphenylphosphino)ferrocene]dichloropalladium (II). In five steps, 2b was synthesized in an overall yield of 20% based on ethyl [1, 2‐14C]oxalyl chloride. Compound 2b was subsequently converted to [14C] BMS‐477118 in a short sequence. Copyright © 2007 John Wiley & Sons, Ltd.