bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crosslinkable polyurethane bearing a methacrylate structure in the side chain
Authors: Ochiai Bungo , Sato Shin‐Ich , Endo Takeshi 
Published: June 2007

AbstractA polyurethane bearing methacrylate groups through urethane linkages was prepared by the addition of 2‐methacryloyloxyethyl isocyanate to the hydroxyl groups in poly(hydroxyurethane) prepared by the polyaddition of a bifunctional cyclic carbonate with 1,12‐diaminododecane. The urethanization proceeded quantitatively in the presence of a catalytic amount of di‐n‐butyltin dilaurate at an ambient temperature, whereas a crosslinked product was obtained from the reaction at 60 °C. The resulting linear polyurethane, bearing a methacrylate structure, was thermally crosslinkable. Its radical copolymerization with vinyl‐type monomers afforded the corresponding crosslinked polymers, whose low glass transition temperatures suggested the flexibility of the polymer chains in the crosslinked product. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3400–3407, 2007
Comparison of ground and excited state polarizabilities of thiophene, cyclopentadiene, and fulvene oligomers and their cyano substituted derivatives—Ab initio study
Authors: Ferdous Sultana , Lagowski Jolanta B. 
Published: June 2007

AbstractAb Initio study of the ground and excited state polarizabilities of thiophene, fulvene, and cyclopentadiene based conducting oligomers and their cyano derivatives have been performed using the restricted Hartree–Fock (RHF) and the configuration interaction singles (CIS) approaches, respectively, with 3‐21G* basis set. For comparison purposes, for some small oligomers (monomers and dimers), higher basis sets (6‐31G*, 6‐31+G*, aug‐cc‐pVTZ) were also employed in the computations of polarizabilities. The trends in polarizability as a function of oligomer length were investigated. For all systems, the RHF polarizability increases as n1.2–1.3 as n gets larger and the CIS polarizability increases as n1.4–1.6 for n less than seven or eight rings and then increases approximately linearly with n for larger n. For the thiophene based systems the dependence of the polarizability on bond length alternation (BLA) along the backbone of the oligomers was also investigated using the RHF, density functional (DFT), and CIS theories (with 3‐21G* basis set). For thiophene dimer, we also performed RHF/aug‐cc‐pVTZ calculations of polarizabilities versus BLA. We found that the polarizability is largest when BLA is near zero (for both ground and excited states), which correlates with the lowest excitation energy. Comparison with experimental results has been made where possible. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1983–1995, 2007
Water vapor sorption and diffusion in sulfonated aromatic polyamides
Authors: Vicente María S. , Gottifredi Juan C. , de la Campa José G. , Lozano Angel E. , Abajo Javier de 
Published: June 2007

AbstractIn this contribution polyamides with different sulfonation degrees were directly synthesized from a combination of sulfonated and nonsulfonated diamines and isophthaloyl chloride. They were then used as dense membranes to study water sorption and mass transport properties. The polymers were characterized by their inherent viscosity and by spectroscopic methods, and the water vapor unsteady sorption phenomena were studied using a gravimetric technique. The effect of sulfonation substitution concentration in these polymers produces very interesting and original results in a number of properties such as the ionic exchange capacity, water equilibrium sorption and diffusivity. Obtained results are discussed and explained in the light of existing theories. Sorption behavior for polymers with a low sulfonation degree, up to 30%, can be explained with Langmuir equation. With larger substitution degree (40 and 60%) an additional mechanism must be assumed to explain sorption data. Assuming the presence of two phases helps to explain the observed diffusivity results. The mass transport mechanism is assumed to be Fickian. When water activity is low diffusivity systematically decreases as the degree of sulfonation increases. However, as water activity increases less sulfonated and nonsulfonated (PA0, PA20 and PA30) behave completely different from PA40 and PA60. The first group of polymers shows a tendency to decrease the rate of diffusion as water activity increases while the second group shows the opposite behavior, with a maximum in diffusivity at intermediate water activities. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2007–2014, 2007
Inverse gas chromatographic characterization of triblock copolymer of polystyrene–poly(ethylene oxide)–polystyrene
Authors: Zou Qi‐Chao , Wu Li‐Min 
Published: June 2007

AbstractThe thermodynamic properties of triblock copolymer of polystyrene–poly (ethylene oxide)–polystyrene (PS‐b‐PEO‐b‐PS) were investigated by means of inverse gas chromatography (IGC) using 15 different kinds of solvents as the probes. Some thermodynamic parameters, such as specific retention volume, molar heats of sorption, weight fraction activity coefficient, Flory‐Huggins interaction parameter, partial molar heats of mixing and solubility parameter were obtained to judge the interactions between PS‐b‐PEO‐b‐PS polymers and solvents and the solubility of the polymers in these solvents. It was found that increasing PEO content in PS‐b‐PEO‐b‐PS resulted in the increase in the solubility of PS‐b‐PEO‐b‐PS in alkanes and acetates solvents, but the solubility in alcohols had no change, and more PEO content in polymer caused a small decrease in the solubility parameter of PS‐b‐PEO‐b‐PS polymer, © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2015–2022, 2007
Effects of elastomer on morphology, flammability and rheological properties of HIPS/PS‐encapsulated Mg(OH)2 composites
Authors: Chang Suqin , Xie Tingxiu , Yang Guisheng 
Published: June 2007

AbstractThe effects of elastomer type on morphology, flammability and rheological properties of high‐impact polystyrene/Mg(OH)2 based on encapsulated by polystyrene have been investigated. The ternary composites characterized by cone calorimetry, horizontal burning rate, limiting oxygen index (LOI), rheology and SEM. Morphology was controlled using poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] triblock copolymer (SEBS) or the corresponding maleinated SEBS (SEBS‐g‐MA). As revealed by SEM observations, composites of HIPS/SEBS/Mg(OH)2 exhibit separation of the filler and elastomer and good adhesion between SEBS and the filler, whereas composites of HIPS/SEBS‐g‐MA/Mg(OH)2 exhibit encapsulation of the filler by SEBS‐g‐MA. The flame retardant and rheological properties of ternary composites were strongly dependent on microstructure. The rheological test showed that the composites with encapsulation structure exhibit a stronger solid‐like response at low frequency than those of the composites with separate dispersion structure. The combustion tests showed that the composites with encapsulation structure showed higher flame retardant properties than those of separate dispersion structure at optimum use level of SEBS‐g‐MA. However, with the increase of the content of SEBS‐g‐MA, the flame retardancy of the composite declined somewhat which can be explained that the SEBS‐g‐MA coating acts as a heat and mass transfer barrier due to the formation of encapsulation structure. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2023–2030, 2007
Uptake of pesticides from water by curly waterweed Lagarosiphon major and lesser duckweed Lemna minor
Authors: de Carvalho Renato F , Bromilow Richard H , Greenwood Richard 
Published: June 2007

AbstractThe uptake of pesticides from water by two aquatic plants, the submersed Lagarosiphon major (Ridley) Moss and the floating duckweed Lemna minor L., was measured over periods of up to 72 h. Twelve non‐ionised pesticides and analogues, chosen to span a wide range of physicochemical properties, and one analogue (3,5‐D) of the phenoxyacetic acid herbicide 2,4‐D were studied. Concentrations of the parent compound were determined in the plants following extraction and separation by chromatography. Quantification was by liquid scintillation counting for the 14C‐labelled compounds and by high‐performance liquid chromatography for the four non‐radiolabelled commercial pesticides. Uptake for all compound and plant combinations had reached equilibrium by 24 h. Accumulation of compound in the plant could be described well for most non‐ionised compounds by equilibration into the aqueous phase in the plant cells together with partitioning onto the plant solids, this latter process becoming dominant in Lagarosiphon for compounds with log Kow > 1 and in Lemna for compounds with log Kow > 1.8. Lipophilic compounds with log Kow > 4 were concentrated more than 100‐fold on a fresh‐weight basis. However, the uptake of isoproturon and chlorotoluron was up to threefold less than expected from their Kow values, and their behaviour was better explained using solvation descriptors. Uptake of the acid 3,5‐D was dependent on solution pH, this compound being strongly taken up at lower pH by the process of ion trapping, as previously observed in barley roots. Aquatic vegetation can thus rapidly accumulate pesticides, and could be an important sink especially for lipophilic pesticides reaching well‐vegetated waters. Copyright © 2007 Society of Chemical Industry
Juvenile hormonal activity of mono‐ and polyenehomobenzenes in Drosophila virilis, Spodoptera frugiperda and Araschnia levana
Authors: Demuth Martin , Zambrano Jorge L , Rosales Viale , Lorenz Matthias W 
Published: June 2007

AbstractA series of mono‐ and polyenehomobenzenes was synthesised by a highly regioselective palladium‐catalysed allylic alkylation of substituted and unsubstituted benzylic Grignard reagents employing catalytic amounts of catalyst and tested for juvenile hormone activity on the fruit fly Drosophila virilis Sturtevant (Diptera: Drosophilidae), on an important agricultural pest species, the fall armyworm Spodoptera frugiperda JE Smith (Lepidoptera: Noctuidae), and on the map butterfly Araschnia levana L. (Lepidoptera: Nymphalidae). In D. virilis only polyenehomobenzenes with a geranyl chain and a methyl, methoxy or isopropyl group at the para position of the aromatic ring displayed significant juvenile hormonal activity at low doses. A monoenehomobenzene and polyenehomobenzenes with longer allylic chains or without a substituted aromatic ring were not active. In S. frugiperda and in A. levana, a mono‐, a di‐ and a tetraene displayed juvenile hormonal activity. In the lepidopteran species, a trend for the necessity of a substitution at position 4 of the phenyl group for high juvenile hormonal activity was also found. Copyright © 2007 Society of Chemical Industry
Development and validation of an infant morbidity index using latent variable models
Authors: Liu Xuefeng , Roth Jeffrey 
Published: June 2007

AbstractBirth defect, abnormal condition of the newborn, developmental delay or disability and low birth weight are four major infant morbidity outcomes. Most studies have focused on assessment of the effects of risk factors on each of these outcomes or of the relationship among these outcomes or both. Little attention has been paid to the development of a composite index, which is a summary construct of infant morbidity outcomes. In this paper, we develop extended latent variable (LV) models and modified Gauss–Newton algorithms for multiple multinomial morbidity outcomes with complete responses. By assuming the marginal distribution of the LV to be log‐normal, we model the conditional probability of each outcome as a nonlinear
function of the LV, which has properties similar to the logistic function. The estimated generalized nonlinear least‐square method is used to solve equations for parameters of interest. The models are applied to an infant morbidity data set. A new single variable, called infant morbidity index (IMI) that functions as a summary of four infant morbidity outcomes and represents propensity for infant morbidity, is developed. The validity of this index is then assessed in detail. It is shown that the IMI is correlated with each of the individual outcomes, with infant mortality and with a face‐valid index of morbidity outcomes, and can be used in future research as a measure of propensity for infant morbidity. Copyright © 2007 John Wiley & Sons, Ltd.
Impact of nuchal cord on measurement of fetal nuchal translucency thickness
Authors: Scheier M. , Egle D. , Himmel I. , Ramoni A. , Viertl S. , Huter O. , Marth C. 
Published: June 2007

AbstractObjectiveTo define the impact of nuchal cord on the measurement of fetal nuchal translucency thickness (NT).MethodsBetween December 2004 and June 2006, we examined prospectively 53 fetuses that were observed on routine first‐trimester ultrasound examination between 11 + 3 and 13 + 6 weeks of gestation to have nuchal cord causing an indentation in the skin in the nuchal region. The fetuses were re‐examined after a median interval of 132 min, when the cord was no longer around the neck and indentation of the skin had resolved. Various NT measurements (highest, lowest, mean) with the cord located around the neck (nuchal cord) were compared with NT measurements in the absence of nuchal cord (‘true’ NT) in the same fetuses. Measurements were considered to be equal when they were within mean ± 1.96 SD, defined by our own intraobserver repeatability according to the method of Bland and Altman.ResultsThe mean of the largest and the smallest of six measurements in the presence of nuchal cord fell within the mean ± 1.96 SD of our own intraobserver repeatability, i.e. gave a correct estimate of the true NT, in 80% of fetuses, while the NT was overestimated in 10% and underestimated in 10% of fetuses. The largest and the smallest of six measurements in the presence of nuchal cord gave an underestimate of the true NT in 2% of fetuses and an overestimate in 4% of fetuses, respectively.ConclusionThere is a wide scattering of measurements in fetuses with nuchal cord in comparison to the same fetuses in the absence of nuchal cord. This prevents accurate prediction of the true NT, although the largest and smallest of repeat measurements with nuchal cord can allow calculation of the highest and lowest possible risks, respectively. These facts must be taken into consideration in counseling patients. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
A dynamic channel assignment scheme for clustered multihop cellular networks
Authors: Li Xue Jun , Chong Peter Han Joo 
Published: June 2007

AbstractWhereas cellular systems have traditionally adopted single‐hop transmissions between the mobile station (MS) and the base station (BS), researchers expect multihop transmission to be utilised in the future. Cellular systems present several challenges, such as channel assignment, which are exacerbated by multimedia service traffic and an increasing number of subscribers. Recently, a clustered multihop cellular network (cMCN) architecture that complements traditional cellular systems has been proposed and studied using fixed channel assignment (FCA). However, the performance of FCA is limited when the traffic pattern varies in a service area. This paper proposes the use of dedicated information ports (DIPs) as clusterheads in cMCN, followed by a multihop dynamic channel assignment (mDCA) scheme. The mDCA works by assigning channels based on information about interference in surrounding cells. Two different channel searching strategies are developed and evaluated. Through computer simulation, we show that the proposed mDCA is able to achieve a significantly improved capacity which is maintained when the number of system channels is increased. Finally, issues regarding the implementation of the mDCA and future work on this topic are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Cytochrome P450 2C9 is involved in flow‐dependent vasodilation of peripheral conduit arteries in healthy subjects and in patients with chronic heart failure
Authors: Fischer Dieter , Landmesser Ulf , Spiekermann Stephan , Hilfiker‐Kleiner Denise , Hospely Marian , Müller Maja , Busse Rudi , Fleming Ingrid , Drexler Helmut 
Published: June 2007

AbstractBackgroundFlow‐mediated dilation (FMD) of human conduit arteries is, in part, related to shear stress‐induced release of endothelium‐derived nitric oxide (NO). However, NO synthase inhibitors do not completely abolish this FMD‐response. Recently, a cytochrome P450 (CYP) epoxygenase of the 2C family was linked to NO‐ and prostacyclin‐independent relaxation of conduit arteries. We therefore evaluated the contribution of CYP 2C9 to FMD in humans.Methods and resultsFMD of the radial artery was determined in 12 healthy volunteers by high‐resolution ultrasound and analyzed before and after intra‐arterial infusion of sulfaphenazole, a specific CYP 2C9 inhibitor, L‐NMMA (NO synthase inhibitor) and co‐infusion of both. Endothelium‐independent vasodilation was characterized after intra‐arterial infusion of SNP. FMD was reduced after sulfaphenazole (11.5±0.87% vs. 7.4±0.95%, p<0.01), after L‐NMMA (6.0±0.71%; p<0.01), and after co‐infusion 3.9±0.73% (p<0.05 vs. L‐NMMA; p<0.01 vs. sulfaphenazole). Sulfaphenazole had no effect on endothelium‐independent vasodilation. In patients with chronic heart failure, the portion of FMD blocked by sulfaphenazole was not affected. CYP 2C was detected by immunohistochemistry in radial artery samples obtained from patients undergoing coronary bypass surgery.ConclusionsFMD in human conductance arteries is reduced after inhibition of CYP 2C9, supporting the concept that CYP 2C metabolites contribute to endothelium‐mediated vasodilation of peripheral conduit arteries in vivo. In patients with heart failure, the CYP‐dependent FMD appears to be preserved.
Low‐volume, high‐throughput sandwich immunoassays for profiling plasma proteins in mice: Identification of early‐stage systemic inflammation in a mouse model of intestinal cancer
Authors: Forrester Sara , Hung Kenneth E. , Kuick Rork , Kucherlapati Raju , Haab Brian B. 
Published: June 2007

AbstractMouse models of human cancers may provide a valuable resource for the discovery of cancer biomarkers. We have developed a practical strategy for profiling specific proteins in mouse plasma using low‐volume sandwich‐immunoassays. We used this method to profile the levels of 14 different cytokines, acute‐phase reactants, and other cancer markers in plasma from mouse models of intestinal tumors and their wild‐type littermates, using as little as 1.5μl of diluted plasma per assay. Many of the proteins were significantly and consistently up‐regulated in the mutant mice. The mutant mice could be distinguished nearly perfectly from the wild‐type mice based on the combined levels of as few as three markers. Many of the proteins were up‐regulated even in the mutant mice with few or no tumors, suggesting the presence of a systemic host response at an early stage of cancer development. These results have implications for the study of host responses in mouse models of cancers and demonstrate the value of a new low‐volume, high‐throughput sandwich‐immunoassay method for sensitively profiling protein levels in cancer.
Analysis of Pathway Activity in Primary Tumors and NCI60 Cell Lines Using Gene Expression Profiling Data
Authors: Feng Xing-Dong , Huang Shu-Guang , Shou Jian-Yong , Liao Bi-Rong , Yingling Jonathan M. , Ye Xiang , Lin Xi , Gelbert Lawrence M. , Su Eric W. , Onyia Jude E. , Li Shu-Yu 
Published: June 2007

Abstract
To determine cancer pathway activities in nine types of primary tumors and NCI60 cell lines, we applied an in silico approach by examining gene signatures reflective of consequent pathway activation using gene expression data. Supervised learning approaches predicted that the Ras pathway is active in ~70% of lung adenocarcinomas but inactive in most squamous cell carcinomas, pulmonary carcinoids, and small cell lung carcinomas. In contrast, the TGF-β, TNF-α, Src, Myc, E2F3, and β-catenin pathways are inactive in lung adenocarcinomas. We predicted an active Ras, Myc, Src, and/or E2F3 pathway in significant percentages of breast cancer, colorectal carcinoma, and gliomas. Our results also suggest that Ras may be the most prevailing oncogenic pathway. Additionally, many NCI60 cell lines exhibited a gene signature indicative of an active Ras, Myc, and/or Src, but not E2F3, β-catenin, TNF-α, or TGF-β pathway. To our knowledge, this is the first comprehensive survey of cancer pathway activities in nine major tumor types and the most widely used NCI60 cell lines. The “gene expression pathway signatures” we have defined could facilitate the understanding of molecular mechanisms in cancer development and provide guidance to the selection of appropriate cell lines for cancer research and pharmaceutical compound screening.
A Survey of the Availability of Primary Bioinformatics Web Resources
Authors: Thireou Trias , Spyrou George , Atlamazoglou Vassilis 
Published: June 2007

Abstract
The explosive growth of the bioinformatics field has led to a large amount of data and software applications publicly available as web resources. However, the lack of persistence of web references is a barrier to a comprehensive shared access. We conducted a study of the current availability and other features of primary bioinformatics web resources (such as software tools and databases). The majority (95%) of the examined bioinformatics web resources were found running on UNIX/Linux operating systems, and the most widely used web server was found to be Apache (or Apache-related products). Of the overall 1,130 Uniform Resource Locators (URLs) examined, 91% were highly available (more than 90% of the time), while only 4% showed low accessibility (less than 50% of the time) during the survey. Furthermore, the most common URL failure modes are presented and analyzed.
IL‐3 receptor expression, regulation and function in cells of the Vasculature.
Authors: KORPELAINEN EIJA I , GAMBLE JENNIFER R , VADAS MATHEW A , LOPEZ ANGEL F 
Published: June 2007

SummaryIL‐3 is a haemopoietic growth factor which stimulates the production and functional activity of various blood cell types. Recent evidence suggests that the target cell population of IL‐3 is not restricted to haemopoietic cells as previously thought, but vascular cells such as endothelial cells also express receptors for and respond to this cytokine. Interestingly, IL‐3 was found to regulate endothelial responses related to inflammation, immunity and haemopoiesis. These findings, summarized in this review, offer new insight into the physiological function of IL‐3 and may also be of clinical importance, as IL‐3 is used in bone marrow reconstitution following cancer therapy.