bluuebunny/crossref_metadata_2025_split huggingface dataset:
Luminescent Determination of Automobile Petrol in Hexane Solutions
Authors: Chukova Oksana , Krut Olexander , Nedilko Sergiy , Sakun Vadim , Scherbatskyi Vasyl 
Published: October 2005

AbstractThe work deals with the problem of determination of automobile petrol of various octane numbers and petroleum contamination of some objects on the basis of analysis of photoluminescence spectra of automobile petrol samples. For this purpose steady state luminescence properties of samples of automobile petrol of different types being in sale were measured. Samples of automobile petrol diluted in hexane were prepared and their luminescence spectra were measured at room and liquid nitrogen temperatures of samples. We constructed concentration dependences of luminescence intensity of both wide band luminescence of liquid solutions obtained at room temperature and peak intensities of luminescence lines of quasi linear spectra of solutions frozen at 77 K. Possibility to use luminescence method for analysis of petrol pollutions on some objects is illustrated by results of investigation of pine‐wood pieces contaminated by automobile petrol.
The Metal Flux: A Preparative Tool for the Exploration of Intermetallic Compounds
Authors: Kanatzidis Mercouri G. , Pöttgen Rainer , Jeitschko Wolfgang 
Published: October 2005

AbstractThis review highlights the use and great potential of liquid metals as exotic and powerful solvents (i.e. fluxes) for the synthesis of intermetallic phases. The results presented demonstrate that considerable advances in the discovery of novel and complex phases are achievable utilizing molten metals as solvents. A wide cross‐section of examples of flux‐grown intermetallic phases and related solids are discussed and a brief history of the origins of flux chemistry is given. The most commonly used metal fluxes are surveyed and where possible, the underlying principal reasons that make the flux reaction work are discussed.
Conformational spaces of the gastrointestinal antisecretory chiral drug omeprazole: Stereochemistry and tautomerism
Authors: Caner Hava , Cheeseman James R. , Agranat Israel 
Published: October 2005

AbstractA study of the conformational spaces of the chiral proton pump inhibitor (PPI) drug omeprazole by semiempirical, ab‐initio, and DFT methods is described. In addition to the chiral center at the sulfinyl sulfur atom, the chiral axis at the pyridine ring (due to the hindered rotation of the 4‐methoxy substituents) was considered. The results were analyzed in terms of the 5‐methoxy and 6‐methoxy tautomers and the two pairs of enantiomers (R,P)/(S,M) and (R,M)/(S,P). Five torsion angles were systematically explored: the backbone rotations defined by D1 (N3–C2–S10–O11), D2 (C2–S10–C12–C13), and D3 (S10–C12–C13–N14) and two methoxy rotations defined by D4 (C6–C5–O8–C9) and D5 (C16–C17–O19–C20). Significant energy differences were revealed between the 5‐ and 6‐methoxy tautomers, the extended and folded conformations, and the (S,M) and (S,P) diastereomers. The “extended M” conformation of the 6‐methoxy tautomer of (S)‐omeprazole was found to be the most stable conformer. © 2005 Wiley‐Liss, Inc. Chirality
In Situ 1H NMR Study on the Trioctylphosphine Oxide Capping of Colloidal InP Nanocrystals
Authors: Hens Zeger , Moreels Iwan , Martins Jose C. 
Published: October 2005

AbstractWe used trioctylphosphine oxide (TOPO) capped colloidal InP nanocrystals (Q‐InP|TOPO) to explore the potential of solution 1H NMR spectroscopy in studying in situ the capping and capping exchange of sterically stabilized colloidal nanocrystals. The spectrum of Q‐InP|TOPO shows resonances of free TOPO, superimposed on broadened spectral features. The latter were assigned to TOPO adsorbed at Q‐InP by means of pulsed field gradient diffusion NMR and 1H‐13C HSQC spectroscopy. The diffusion coefficient of Q‐InP|TOPO nanocrystals was inferred from the decay of the adsorbed TOPO NMR signal. The corresponding hydrodynamic diameter correlates well with the diameter of Q‐InP. By using the resolved methyl resonance of adsorbed TOPO, the packing density of TOPO at the InP surface can be estimated. Spectral hole burning was used to demonstrate explicitly that the adsorbed TOPO resonances are heterogeneously broadened. Exchange of the TOPO capping by pyridine was demonstrated by the disappearance of the resonances for adsorbed TOPO and the appearance of pyridine resonances in the 1H NMR spectrum. These results show that solution NMR spectroscopy should be considered a powerful technique for the in situ study of the capping of sterically stabilized colloidal nanocrystals.
Importin α mRNAs have distinct expression profiles during spermatogenesis
Authors: Hogarth Cathryn A. , Calanni Sophina , Jans David A. , Loveland Kate L. 
Published: October 2005

AbstractImportin proteins control access to the cell nucleus by mediating the nuclear transport of specific cargoes. We hypothesized that developmental regulation of gene expression may be partially effected by changes in the nuclear transport machinery complement, manifested as regulated expression of importin α family genes. We first clarified the identity of the five known mouse importin α genes relative to those for human and then determined their expression throughout postnatal rodent testis using PCR and in situ hybridization. Distinct expression patterns were observed for each. At 10 dpp, all importin α mRNAs were detected in spermatogonia. In the adult mouse testis,importinsα1andα3were detected in spermatogonia and early pachytene spermatocytes.Importin α4mRNA was identified in pachytene spermatocytes,α6mRNA in round spermatids, andα2mRNA in both of these. The distinct importin α expression patterns are consistent with their having specific roles and transport cargoes during spermatogenesis. Developmental Dynamics 235:253–262, 2006. © 2005 Wiley‐Liss, Inc.
Circadian clock and cell cycle gene expression in mouse mammary epithelial cells and in the developing mouse mammary gland
Authors: Metz Richard P. , Qu Xiaoyu , Laffin Brian , Earnest David , Porter Weston W. 
Published: October 2005

AbstractMouse mammary epithelial cells (HC‐11) and mammary tissues were analyzed for developmental changes in circadian clock, cellular proliferation, and differentiation marker genes. Expression of the clock genes Per1 and Bmal1 were elevated in differentiated HC‐11 cells, whereas Per2 mRNA levels were higher in undifferentiated cells. This differentiation‐dependent profile of clock gene expression was consistent with that observed in mouse mammary glands, as Per1 and Bmal1 mRNA levels were elevated in late pregnant and lactating mammary tissues, whereas Per2 expression was higher in proliferating virgin and early pregnant glands. In both HC‐11 cells and mammary glands, elevated Per2 expression was positively correlated with c‐Myc and Cyclin D1 mRNA levels, whereas Per1 and Bmal1 expression changed in conjunction with β‐casein mRNA levels. Interestingly, developmental stage had differential effects on rhythms of clock gene expression in the mammary gland. These data suggest that circadian clock genes may play a role in mouse mammary gland development and differentiation. Developmental Dynamics 235:263–271, 2006. © 2005 Wiley‐Liss, Inc.
A 3′ cis‐regulatory region controls wingless expression in the Drosophila eye and leg primordia
Authors: Pereira P.S. , Pinho S. , Johnson K. , Couso J.P. , Casares F. 
Published: October 2005

AbstractThe precise regulation of wingless (wg) expression in the Drosophila eye disc is key to control the anteroposterior and dorsoventral patterning of this disc. Here, we identify an eye disc‐specific wg cis‐regulatory element that functions as a regulatory rheostat. Pannier (Pnr), a transcription factor previously proposed to act as an upstream activator of wg, is sufficient to activate the eye disc enhancer but required for wg expression only in the peripodial epithelium of the disc. We propose that this regulation of wg by Pnr appeared associated to the development of the peripodial epithelium in higher dipterans and was added to an existing mechanism regulating the deployment of wingless in the dorsal region of the eye primordium. In addition, our analysis identifies a separate ventral disc enhancer that lies adjacent to the eye‐specific one, and thus altogether, they define a 1‐kb genomic region where disc‐specific enhancers of the wg gene are located. Developmental Dynamics 235:225–234, 2006. © 2005 Wiley‐Liss, Inc.
Copolymer effects on microglia and T cells in the central nervous system of humanized mice
Authors: Illes Zsolt , Stern Joel N. H. , Keskin Derin B. , Reddy Jayagopala , Brosnan Celia F. , Waldner Hanspeter , Santambrogio Laura , Kuchroo Vijay K. , Strominger Jack L. 
Published: October 2005

AbstractThe random amino acid copolymers FYAK and VWAK ameliorate EAE in a humanized mouse model expressing both a human transgenic myelin basic protein (MBP)85–99‐specific T cell receptor and HLA‐DR2. Here we show that microglia isolated from the central nervous system (CNS) of humanized mice with EAE induced by MBP85–99 and treated with these copolymers had reduced expression of HLA‐DR, and thus reduced capacity to present MBP85–99 and activate transgenic T cells. In vitro microglia up‐regulated empty HLA‐DR2 upon activation with GM‐CSF with or without LPS or IFN‐γ, but not with IL‐4 or IL‐10. Correspondingly, gene chip arrays showed that the CNS of untreated and YFAK‐treated mice differentially expressed pro‐ and anti‐inflammatory molecules during MBP85–99‐induced EAE. Interestingly, microglia expressed the full‐length γβ and αβ subunits of the tetrameric adaptor protein complexes AP‐1 and AP‐2 respectively, but after treatment with GM‐CSF these complexes were cleaved, as had been found in immature dendritic cells derived from bone marrow. Strikingly, in vivo the perivascular lymphocyte infiltration seen in untreated mice immunized with MBP85–99 was composed of equal numbers of hVβ2+ MPB85–99‐specific transgenic and hVβ2– endogenous T cells, while the much smaller infiltration seen after treatment with YFAK was composed predominantly of hVβ2– endogenous T cells.
Genetic control of thymic development of CD4+CD25+FoxP3+ regulatory T lymphocytes
Authors: Romagnoli Paola , Tellier Julie , van Meerwijk Joost P. M. 
Published: October 2005

AbstractAmong the several mechanisms known to be involved in the establishment and maintenance of immunological tolerance, the activity of CD4+CD25+ regulatory T lymphocytes has recently incited most interest because of its critical role in inhibition of autoimmunity and anti‐tumor immunity. Surprisingly, very little is known about potential genetic modulation of intrathymic regulatory T lymphocyte development. We show that distinct proportions of CD4+CD25+FoxP3+ regulatory T cells are found in thymi of common laboratory mouse strains. We demonstrate that distinct levels of phenotypically identical regulatory T cells develop with similar kinetics in the mice studied. Our experimental data on congenic mouse strains indicate that differences are not caused by the distinct MHC haplotypes of the inbred mouse strains. Moreover, the responsible loci act in a thymocyte‐intrinsic manner, confirming the latter conclusion. We have not found any correlation between thymic and peripheral levels of regulatory T cells, consistent with known homeostatic expansion and/or retraction of the peripheral regulatory T cell pool. Our data indicate that polymorphic genes modulate differentiation of regulatory T cells. Identification of responsible genes may reveal novel clinical targets and still elusive regulatory T cell‐specific markers. Importantly, these genes may also modulate susceptibility to autoimmune disease.
Assessment of the Reusability of Pd Complexes Supported on Fluorous Silica Gel as Catalysts for Suzuki Couplings
Authors: Tzschucke Carl Christoph , Andrushko Vasyl , Bannwarth Willi 
Published: October 2005

AbstractA thorough investigation of different perfluoro‐tagged Pd complexes supported on fluorous silica gel (FSG) as catalysts for Suzuki reactions is presented. The rates of reaction upon recycling of the supported complexes were measured in order to determine the reusability of the catalysts. Perfluoro‐tagged and untagged complexes adsorbed on FSG and unmodified silica gel were also compared. While with dimethoxyethane (DME) as a solvent the catalytic activity decreased upon reuse, significant activity was retained with recycled catalysts for reactions in water. With catalyst loadings of 0.001 mol‐%, TONs as high as 526000 were obtained. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Solution‐Phase Synthesis of Phosphorothioate Oligonucleotides Using a Solid‐Supported Acyl Chloride with H‐Phosphonate Chemistry
Authors: Adamo Ilaria , Dueymes Cécile , Schönberger Andreas , Navarro Aude‐Emmanuelle , Meyer Albert , Lange Meinolf , Imbach Jean‐Louis , Link Fritz , Morvan François , Vasseur Jean‐Jacques 
Published: October 2005

AbstractThe synthesis of oligonucleotides from dimers to a hexamer by a H‐phosphonate approach in solution using solid‐supported acyl chloride is reported herein. This strategy avoids the use of chromatography. The work‐ups have been simplified and involve filtration, aqueous extraction and precipitation. The synthesis was scaled up to 1 mmol for the dimers and 340 μmol for the hexamer. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Electrochemical Response of Cobalt(II) in the Presence of Ammonia
Authors: Ji Xiaobo , Buzzeo Marisa C. , Banks Craig E. , Compton Richard G. 
Published: October 2005

AbstractThe electrochemical oxidation of cobalt(II) at gold, boron‐doped diamond, basal and edge plane pyrolytic graphite, and highly oriented pyrolytic graphite electrodes in aqueous solutions containing NH3 has been studied using cyclic voltammetry, with subsequent chemical and electrochemical processes explained in detail. Furthermore, the electro‐reduction of [Co(NH3)6]3+ in the presence of different electrolytes has also been studied to obtain a better understanding of the oxidation pathway of the Co(II)‐ammine complexes. In aqueous solution the mechanism can be described by the following scheme:
Sometimes more equal than others: how health inequalities depend on the choice of welfare indicator
Authors: Lindelow Magnus 
Published: October 2005

AbstractIn recent years, a large body of empirical work has focused on measuring and explaining socio‐economic inequalities in health outcomes and health service use. In any effort to address these questions, analysts must confront the issue of how to measure socioeconomic status. In developing countries, socioeconomic status has typically been measured by per capita consumption or an asset index. Currently, there is only limited information on how the choice of welfare indicators affect the analysis of health inequalities and the incidence of public spending. The purpose of this paper is to illustrate the potential sensitivity of the analysis of health related inequalities to how socioeconomic status is measured. Using data from Mozambique, the paper focuses on five key health service indicators, and tests whether measured inequality (concentration index) in health service utilization differs depending on the choice of welfare indicator. The paper shows that, at least in some contexts, the choice of welfare indicator can have a large and significant impact on measured inequality in utilization of health services. In consequence, we can reach very different conclusions about the ‘same’ issue depending on how we define socioeconomic status. The paper also provides some tentative conclusions about why and in what contexts health inequalities can be sensitive to the choice of living standards measure. The results call for more clarity and care in the analysis of health related inequalities, and for explicit recognition of the potential sensitivity of findings to the choice of welfare measure. The results also point at the need for more careful research on how different dimensions of SES are related, and on the pathways by which the respective different dimensions impact on health related variables. Copyright © 2005 John Wiley & Sons, Ltd.
Responses of excitatory hippocampal synapses to natural stimulus patterns reveal a decrease in short‐term facilitation and increase in short‐term depression during postnatal development
Authors: deKay James G.T. , Chang Tony C. , Mills Nadia , Speed Haley E. , Dobrunz Lynn E. 
Published: October 2005

AbstractSchaffer collateral excitatory synapses onto CA1 pyramidal cells are subject to significant modulation by short‐term plasticity. This presynaptic, history‐dependent modulation of neurotransmitter release causes synaptic transmission to be sensitive to the frequency of the input. As a result, temporally irregular input patterns, such as those observed in vivo, produce synaptic responses over a very wide dynamic range that reflect a balance of short‐term facilitation and short‐term depression. The neonatal period is an important developmental period in the hippocampus, when functional representations of an animal's environment are being established through exploratory behavior. The strength of excitatory synapses and their modulation by short‐term plasticity are critical to this process. One form of short‐term plasticity, paired‐pulse facilitation, has been shown to decrease as juvenile rats mature into young adults. However, little is known about the neonatal modulation of other forms of short‐term plasticity, including the responses to temporally complex stimuli. We examined developmental modulation of the short‐term dynamics of Schaffer collateral excitatory synapses onto CA1 pyramidal cells in acute hippocampal slices, using both constant frequency stimuli and natural stimulus patterns that were taken from in vivo recording of spike patterns of hippocampal cells. In response to constant frequency stimulation, synapses in slices from young adult rats (P28–P35) showed less short‐term depression than did those in slices from juveniles (P12–P18). However, when the natural stimulus pattern (containing a wide mix of frequencies) was used, synapses from young adults instead showed more short‐term depression and less short‐term facilitation than did juveniles. Comparing the natural stimulus pattern responses with constant frequency stimulation of a similar frequency, we found that the average responses were similar in young adults (both showed modest depression). However, in juveniles, the natural pattern produced robust facilitation while constant frequency stimulation caused a large short‐term depression. Our results reveal that there are developmental changes both in individual forms of short‐term plasticity and in the relative balance between short‐term facilitation and short‐term depression that will alter the signal transfer characteristics of these synapses. © 2005 Wiley‐Liss, Inc.
Estimating amount and spatial distribution of groundwater recharge in the Iullemmeden basin (Niger) based on 3H, 3He and CFC‐11 measurements
Authors: Rueedi J. , Brennwald M. S. , Purtschert R. , Beyerle U. , Hofer M. , Kipfer R. 
Published: October 2005

AbstractA new approach is presented to estimate the amounts and spatial distribution of groundwater recharge based on the groundwater dating tracers 3H, 3He and CFC‐11. The method was applied in a groundwater project in southwest Niger (Africa). The model developed to simulate observed tracer concentrations is composed of a model to account for the water transported through the unsaturated zone followed by a dispersion box model to determine the age distribution of the sampled groundwater volume. For the unsaturated zone transport, a one‐dimensional approach was used considering tracer transport in the water and the gas phase. The calculated tracer concentrations at the groundwater table are then used as input functions for the subsequent dispersion box model. Using a dispersion box model it is possible to outline regions where recharge preferably occurs. To account for the high variance of soil properties in space, a Monte Carlo simulation was performed.The results show estimated recharge rates of 50–300 mm year−1 (±50%). The large error bars are mainly due to high uncertainties of the soil parameters. Therefore, a better estimation of the average soil moisture would lead to more accurate results. The resulting spatial distribution of dispersion parameters indicates that recharge mainly occurs in the ancient riverbeds where surface runoff from the laterite plateaux is gathered and leads to spatially limited high recharge events. Where the soil is not permeable enough, these events lead to the observed temporary or permanent lakes. This new conceptual view of major recharge mechanisms contradicts the former picture of recharge occurring in this region, but it coincides better with other independent measurements, such as the stable isotope ratios of water. Copyright © 2005 John Wiley & Sons, Ltd.
Tritium balance modelling in a macroscale catchment
Authors: Koeniger P. , Wittmann S. , Leibundgut Ch. , Krause W. J. 
Published: October 2005

AbstractTritium concentrations measured in precipitation and discharge are combined with hydrological and meteorological information on a monthly basis over a period of 50 years in order to study tritium balances and hydrological interactions in macroscale catchments. Three subcatchments of the Weser River in Germany (Werra 5410 km2, Fulda 6890 km2 and Weser‐1 15 320 km2) were used to test a tritium balance model, to study residence times, groundwater storage behaviour and tritium load of different water balance components. A comparison of measured and modelled tritium concentrations in discharge showed considerable fits with model efficiencies close to 0·7. The estimated residence times for an estimated fast and slow groundwater component are between 5 to 8 years and 7 to 28 years respectively. The results indicate a tritium load of 12 to 14% of the precipitation input over the whole time period moving through groundwater reservoirs and 13 to 16% transported through direct discharge. Copyright © 2005 John Wiley & Sons, Ltd.
Tracing long‐term vadose zone processes at the Nevada Test Site, USA
Authors: Hunt James R. , Tompson Andrew F. B. 
Published: October 2005

AbstractThe nuclear weapons testing programme of the USA has released radionuclides to the subsurface at the Nevada Test Site. One of these tests has been used to study the hydrological transport of radionuclides for over 25 years in groundwater and the deep unsaturated zone. Ten years after the weapon's test, a 16 year groundwater pumping experiment was initiated to study the mobility of radionuclides from that test in an alluvial aquifer. The continuously pumped groundwater was released into an unlined ditch where some of the water infiltrated into the 200 m deep vadose zone. The pumped groundwater had well‐characterized tritium activities that were utilized to trace water migration in the shallow and deep vadose zones. Within the near‐surface vadose zone, tritium levels in the soil water are modelled by a simple one‐dimensional, analytical wetting front model. In the case of the near‐surface soils at the Cambric Ditch experimental site, water flow and salt accumulation appear to be dominated by rooted vegetation, a mechanism not included within the wetting front model. Simulation results from a two‐dimensional vadose groundwater flow model illustrate the dominance of vertical flow in the vadose zone and the recharge of the aquifer with the pumped groundwater. The long‐time series of hydrological data provides opportunities to understand contaminant transport processes better in the vadose zone with an appropriate level of modelling. Copyright © 2005 John Wiley & Sons, Ltd.