bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hedgehog signaling: Endocrine gland development and function
Authors: Cohen M. Michael 
Published: December 2009

AbstractThe role of hedgehog signaling is analyzed in relation to the developing endocrine glands: pituitary, ovary, testis, adrenal cortex, pancreas, prostate, and epiphyseal growth. Experimental and pathological correlates of these organs are also discussed. The second section addresses a number of topics. First, the pituitary gland, no matter how hypoplastic, is present in most cases of human holoprosencephaly, unlike animals in which it is always said to be absent. The difference appears to be that animal mutations and teratogenic models involve both copies of the gene in question, whereas in humans the condition is most commonly heterozygous. Second, tests of endocrine function are not reported with great frequency, and an early demise in severe cases of holoprosencephaly accounts for this trend. Reported tests of endocrine function are reviewed. Third, diabetes insipidus has been recorded in a number of cases of holoprosencephaly. Its frequency is unknown because it could be masked by adrenal insufficiency in some cases and may not be recognized in others. Because of the abnormal hypothalamic‐infundibular region in holoprosencephaly, diabetes insipidus could be caused by a defect in the supra‐optic or paraventricular hypothalamic nuclei or in release of ADH via the infundibulum and posterior pituitary. © 2009 Wiley‐Liss, Inc.
Drug loading onto and release from wheat gluten fibers
Authors: Xu Weijie , Yang Yiqi 
Published: December 2009

AbstractDrug release and its relationship with kinetic and thermodynamic parameters of drug sorption onto wheat gluten (WG) fibers have been studied using Diclofenac, 5‐Fluorouracil (5‐Fu), and Metformin as model drugs. Both sorption and dissolution methods were used to examine the drug release rates in phosphate buffered saline (PBS pH 7.4) and artificial gastric juice (AGJ pH 1.2). To understand drug release of WG fibers using the sorption loading method, kinetic, and apparent thermodynamic parameters, such as diffusion coefficient, activation energy for diffusion, affinity, and sorption enthalpy and entropy, have been investigated. It has been found that the sorption method at high temperatures has a lower initial burst and more constant release than the dissolution method for Diclofenac on WG fibers. Quantitative relationship between drug release and drug loading concentration, affinity, and activation energy for diffusion was established to predict initial bursts and later release of the drugs. The study showed that the Diclofenac had high initial bursts in PBS but more constant release in AGJ because the ionic force between the drug and WG fibers was readily broken in a high pH solution. It also has been found that drugs with higher activation energy for diffusion, lower diffusion coefficients, and higher affinity (especially van der Waals force) on WG fiber, are more suitable for sorption loading at elevated temperatures to achieve higher loading capacity and more constant releasing rate. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of polyurethane properties on mechanical performances of magnetorheological elastomers
Authors: Wei Bing , Gong Xinglong , Jiang Wanquan 
Published: December 2009

AbstractMagnetorheological elastomers (MREs) are mainly composed of magnetizable particles and elastic polymer. The polymer matrix plays an important role in mechanical performances of MREs. In this study, the polyurethane (PU), which is synthesized by using toluene diisocyanate (TDI) and poly (propylene glycol) (PPG‐220), is selected as a matrix because it has better degradation stability than natural rubber and higher mechanical stability than silicone rubber. Four different MRE samples were fabricated by adjusting the reaction molar ratio of TDI to PPG to change the property of PU matrix. Structural characterization of the PU matrix was described by Fourier transform infrared analysis. The microstructures of samples were observed by using an environmental scanning electron microscope. The mechanical performances of samples, including shear modulus, magnetorheological effect (MR) effect, loss factor, and glass transition temperature (Tg), were characterized with dynamic mechanical analyzer. The results show that the shear modulus, the relative magnetic residual shear modulus and glass transition temperatures of samples increase with the increment of toluene diisocyanate, while the relative MR effects and loss factors decrease steadily. The experimental results indicate that optimal molar ratio (TDI : PPG) is 3 : 1. The field‐induced shear modulus of sample with molar ratio 3 : 1 is 4.9 MPa, and the relative MR effect is 121% under an external magnetic field of 800 mT at room temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of the solvent evaporation rate on the crystalline phases of solution‐cast poly(vinylidene fluoride) films
Authors: Chinaglia Dante Luis , Gregorio Rinaldo , Stefanello Josiani Cristina , Pisani Altafim Ruy Alberto , Wirges Werner , Wang Feipeng , Gerhard Reimund 
Published: December 2009

AbstractThe influence of the solvent‐evaporation rate on the formation of α and β crystalline phases in solution‐cast poly(vinylidene fluoride) (PVDF) films was systematically investigated. Films were crystallized from PVDF/N,N‐dimethylformamide solutions with concentrations of 2.5, 5.0, 10, and 20 wt % at different temperatures. During crystallization, the solvent evaporation rate was monitored in situ by means of a semianalytic balance. With this system, it was possible to determine the evaporation rate for different concentrations and temperatures of the solution under specific ambient conditions (pressure, temperature, and humidity). Fourier‐Transform InfraRed spectroscopy with Attenuated Total Reflectance revealed the β‐phase content in the PVDF films and its dependence on previous evaporation rates. Based on the relation between the evaporation rate and the PVDF phase composition, a consistent explanation for the different amounts of β phase observed at the upper and lower sample surfaces is achieved. Furthermore, the role of the sample thickness has also been studied. The experimental results show that not only the temperature but also the evaporation rate have to be controlled to obtain the desired crystalline phases in solution‐cast PVDF films. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Cyclic dithia/diaza with dual Schiff base linkage functionalized polymers for heavy metal adsorption
Authors: Nutthanara Pradit , Ngeontae Wittaya , Imyim Apichat , Kreethadumrongdat Thanapong 
Published: December 2009

AbstractThree new types of functionalized polystyrene‐divinylbenzene resins containing two sulfur and two nitrogen atoms and four nitrogen atoms in cyclic form were prepared by using two lab‐synthesized ligands; 2‐[3‐(2‐amino ethylsulfanyl)‐propylsulfanyl]‐ethylamine (AEPE) and 2‐[2‐(2‐amino‐ethylsulfanyl)‐ethylsulfanyl]‐ethylamine (AEEE), and a commercial one; triethylenetetramine (TETA). Chloromethylated polystyrene‐divinylbenzene copolymer (Cl‐PS‐DVB) was initially oxidized to aldehydic polystyrene‐divinylbenzene (CHO‐PS‐DVB) with approximately 57% yield. CHO‐PS‐DVB was subsequently reacted with the ligands through dual Schiff base linkage. The products were named AEPE‐PS‐DVB, AEEE‐PS‐DVB and TETA‐PS‐DVB, respectively. The optimum coupling reaction times and temperatures were 6 h at 50°C for AEPE‐PS‐DVB, AEEE‐PS‐DVB and 6 h at room temperature for TETA‐PS‐DVB. The appropriate amount of the three ligands was 2.65 mmol/g CHO‐PS‐DVB corresponding to the mole ratio between the chelating ligand and aldehyde group of 1 : 2. All derivative resins were characterized by elemental analysis, thermogravimetry, FT‐IR and FT‐Raman spectroscopy and Ninhydrin test. The adsorption properties of the synthesized resins towards Pb(II), Cu(II), Cd(II), Zn(II), Ni(II), Co(II) and Cr(III) ions in aqueous solution were preliminarily investigated by batch method. AEPE‐PS‐DVB and AEEE‐PS‐DVB showed the same sorption behavior. Their selectivity order was Pb(II) > Zn(II) > Cu(II) > Cd(II) and no significant adsorption for Co(II), Ni(II), Cr(III) was observed. In addition, TETA‐PS‐DVB showed a selectivity toward only Pb(II). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of poly(vinylidene fluoride)/sulfonated poly(phthalazinone ether sulfone ketone) blends for proton exchange membrane
Authors: Gu Shuang , He Gaohong , Wu Xuemei , Hu Zhengwen , Wang Leilei , Xiao Gongkui , Peng Lin 
Published: December 2009

AbstractPoly(vinylidene fluoride)/sulfonated poly(phthalazinone ether sulfone ketone) (PVdF/SPPESK) blend membranes are successfully prepared by solution blending method for novel proton exchange membrane (PEM). PVdF crystallinity, FTIR‐ATR spectroscopy, thermal stability, morphology, water uptake, dimension stability, and proton conductivity are investigated on PVdF/SPPESK blends with different PVdF contents. XRD and DSC analysis reveal that the PVdF crystallinity in the blends depends on PVdF content. The FTIR‐ATR spectra indicate that SPPESK remains proton‐conducting function in the blends due to the intactness of SO3H group. Thermal analysis results show a very high thermal stability (Td1 = 246–261°C) of the blends. PVdF crystallinity and morphology study demonstrate that with lower PVdF content, PVdF are very compatible with SPPESK. Also, with lower PVdF content, PVdF/SPPESK blends possess high water uptake, e.g., P/S 10/90 and P/S 15/85 have water uptake of 135 and 99% at 95°C, respectively. The blend membranes also have good dimension stability because the swelling ratios are at a fairly low level (e.g., 8–22%, 80°C). PVdF/SPPESK blends with low PVdF content exhibit very high proton conductivity, e.g., at 80°C, P/S 15/85 and P/S 10/90 reach 2.6 × 10−2 and 3.6 × 10−2 S cm−1, respectively, which are close to or even higher than that (3.4 × 10−2 S cm−1) of Nafion115 under the same test condition. All above properties indicate that the PVdF/SPPESK blend membranes (particularly, with 10–20% of PVdF content) are very promising for use in PEM field. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Positive temperature coefficient properties of multiwall carbon nanotubes/poly(vinylidene fluoride) nanocomposites
Authors: Jiang S. L. , Yu Y. , Xie J. J. , Wang L. P. , Zeng Y. K. , Fu M. , Li T. 
Published: December 2009

AbstractFavorable positive temperature coefficient (PTC) properties of multiwall carbon nanotubes (MWCNT)/poly(vinylidene fluoride) (PVDF) nanocomposites were obtained. The results showed that such composites presented high PTC intensity, as well as eliminated negative temperature coefficient effect and high thermal stability, which indicated that the MWCNT/PVDF nanocomposites could overcome the main shortages of the current polymer‐based PTC composites. By comparing with other contrastive nanocomposites through similar procedure, the mechanisms for the MWCNT/PVDF composite to overcome the shortages were studied and discussed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Biophysical studies on bone cement composites based on polyester fumarate
Authors: Kamel N. A. , Abou‐Aiaad T. H. , Iskander B. A. , Khalil S. K. H. , Mansour S. H. , Abd‐El‐Messieh S. L. , Abd‐El‐Nour K. N. 
Published: December 2009

AbstractPolypropylene fumarate (PPF) as unsaturated linear polyester crosslinked with three different monomers namely N‐vinyl pyrrolidone (NVP), methyl methacrylate (MMA), and a mixture of NVP/MMA (1 : 1 weight ratio) were prepared. The chemical structure of the PPF was characterized by means of 1H‐NMR, FTIR, as well as GPC. The mixture of PPF resin with the crosslinking monomers filled with (60, 65, and 70 wt %) of gypsum were also prepared as bone cement composites. The dielectric measurements carried out on these prepared samples at frequency range from 100 Hz–100 kHz indicate that the permittivity ε′ and dielectric loss ε″ follow the order NVP > NVP/MMA > MMA. Both parameters were found to decrease by increasing the percentage of gypsum. According to Fröhlich and Havriliak Nagami functions, the relaxation times obtained could be attributed, respectively, to Maxwell‐Wagner effect and to the relaxation process related to carboxyl, hydroxyl, and ester functions associated with main chain. The latter relaxation time was found to increase by increasing gypsum content, whereas the electrical conductivity was found to decrease. The mechanical data of the investigated samples containing 60 wt % gypsum is characterized by the best properties and the behavior of the composites follows the order found in the case of dielectric properties (NVP > NVP/MMA > MMA). Formation of carbonate apatite of composite samples loaded with 60 wt % gypsum after immersing the samples for 4 weeks in simulated body fluid (SBF) was confirmed by the dielectric measurements and FTIR spectroscopy. In addition, the weight loss and the mechanical properties for such systems were also studied. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and properties of highly branched waterborne poly(urethane‐urea) via A2 + B3 approach
Authors: Hu Qian , Liu Dan , Zeng Shaomin , Yi Changfeng , Xu Zushun 
Published: December 2009

AbstractA series of highly branched waterborne poly(urethane‐urea)s (HBWPUs) containing pendant carboxylate anion as the hydrophilic groups were prepared via A2 + B3 approach using isocyanate end‐capped polycarbonatediols as an A2 oligomeric monomer and triamine as a B3 monomer. The structure of the products were characterized by FTIR and 13C‐NMR. The particle size, solution viscosity, thermal and mechanical properties were measured by photon correlation spectroscopy (PCS), rotational rheometer, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA) and tensile tests, respectively. It was found that the particles size mainly depended on the molar ratio of nNCO/nOH and the content of hydrophilic groups; the HBWPUs showed lower viscosity but higher Tg compared with linear waterborne polyurethane. The tensile testing, DMA measurements and rehological measurements revealed that the molar ratio of [B3]/[A2] had significant influence on the viscosity and tensile strength. With increasing the molar ratio of [B3]/[A2], both the viscosity and the tensile strength decreased. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Electrospinning of antibacterial poly(vinylidene fluoride) nanofibers containing silver nanoparticles
Authors: Yuan Jiang , Geng Jia , Xing Zhicai , Shen Jian , Kang Inn‐Kyu , Byun Hongsik 
Published: December 2009

AbstractPoly(vinylidene fluoride) (PVDF) nanofibrous mats containing silver nanoparticles were prepared by electrospinning. The diameter of the nanofibers ranged between 100 and 300 nm, as revealed by scanning electron microscopy. The silver nanoparticles were dispersed, but some aggregation was observed with transmission electron microscopy. The content of silver nanoparticles incorporated into the PVDF nanofibrous mats was determined by inductively coupled plasma and X‐ray photoelectron spectroscopy. The antibacterial activities of the samples were evaluated with the colony‐counting method against Staphylococcus aureus (Gram‐positive) and Klebsiella pneumoniae (Gram‐negative) bacteria. The results indicate that the PVDF nanofibrous mats containing silver nanoparticles showed good antibacterial activity compared to the PVDF nanofiber control. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Comparative delivery of Diltiazem hydrochloride through synthesized polymer: Hydrogel and hydrogel microspheres
Authors: Ray Debajyoti , Gils P. Sunny , Mohanta Guru P. , Manavalan R. , Sahoo Prafulla K. 
Published: December 2009

AbstractIn this study, interpenetrating polymer network (IPN) hydrogel based on polyvinyl alcohol (PVA) networking with polyacrylic acid (PAA) were prepared by a non‐conventional emulsion method without any added crosslinker, using benzoyl peroxide as initiator and sodium chloride (NaCl) as additive. The IPN hydrogel was characterized by using Fourier transformed infrared (FTIR) spectrophotometry, Thermo gravimetric analysis (TGA), and Scanning electron microscopy (SEM). (PVA‐co‐PAA)/NaCl normal IPN hydrogel (H) were fabricated into hydrogel microspheres (HM) by modified emulsion crosslinking method using glutaraldehyde‐saturated toluene as crosslinker and were loaded with Diltiazem hydrochloride (DL). The IPN hydrogel showed more swelling in simulated intestinal fluid (SIF). (PVA‐co‐PAA)/NaCl HM formulation A1 showed comparatively higher DL entrapment (79%) and better control over DL release up to 24 h. By comparing antihypertensive activity of DL loaded two formulations in normotensive rats, HM formulation A1 found more effective in reducing blood pressure to 40.1%. The experimental results demonstrated that (PVA‐co‐PAA)/NaCl HM had the greater potential than normal hydrogel to be used as a drug carrier. A single use of the prepared hydrogel microsphere system of DL can effectively control hypertension in rats. The system holds promise for clinical studies. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Hans Peter Luhn and Herbert M. Ohlman: Their roles in the origins of keyword‐in‐context/permutation automatic indexing
Authors: Williams Robert V. 
Published: December 2009

AbstractThe invention of automatic indexing using a keyword‐in‐context approach has generally been attributed solely to Hans Peter Luhn of IBM. This article shows that credit for this invention belongs equally to Luhn and Herbert Ohlman of the System Development Corporation. It also traces the origins of title derivative automatic indexing, its development and implementation, and current status.
User‐producer interaction in Web site development: Motives, modes, and misfits
Authors: van Rijnsoever Frank J. , Faber Jan , Brinkman Marnix L.J. , van Weele Marijn A. 
Published: December 2009

AbstractThis paper studies the role and effects of user‐producer interaction (UPI) in the production of Web sites. The results of two empirical studies, one from a producer perspective and one from a user perspective, are presented. It is concluded that using UPI in the development of informative Web sites for a large public is a risky process, because it is hard to identify and define the most targeted users and their particular needs. The implications of these results are discussed.
Requirements for the design of a personal document‐management system
Authors: Bondarenko Olha , Janssen Ruud , Driessen Samuël 
Published: December 2009

AbstractIn this article a set of requirements for the design of a personal document management system is presented, based on the results of three research studies (Bondarenko, 2006; Bondarenko & Janssen, 2005; Bondarenko & Janssen, 2009). We propose a framework, based on layers of task decomposition, that helps to understand the needs of information workers with regard to personal document and task management. Relevant user processes are described and requirements for a document‐management system are derived for each layer. The derived requirements are compared to related studies, and implications for system design are discussed.
Human spleen tyrosine kinase (Syk) recombinant expression systems for high‐throughput assays
Authors: Singh Deepika , Rani Reema , Rajendran Resmi , Kaur Namrata Jit , Pandey Abhinav , Chopra Puneet , Jain Tarun , Jain Manish Kumar , Grover Sonam , Arya Ranjana , Saini Kulvinder Singh 
Published: December 2009

AbstractSpleen tyrosine kinase (Syk) is an important non‐receptor tyrosine kinase and its aberrant regulation is associated with a variety of allergic disorders and autoimmune diseases. To identify small molecule inhibitors of Syk in high‐throughput assays, recombinant Syk protein is needed in bulk quantity. We studied the expression of recombinant human Syk in three heterologous systems: E. coli, baculovirus expression vector system (BEVS), and the cellular slime mold Dictyostelium discoideum (Dd). Syk activity was higher in the BEVS as compared to the Dd expression host, whereas in E. coli, no activity was observed under our assay conditions. Purified Syk kinase domain protein from BEVS showed concentration dependent inhibition with OXSI‐2, a known Syk inhibitor. Molecular modeling and docking studies were performed to understand the binding mode and critical interactions of the inhibitor with catalytic domain of Syk. The BEVS generated Syk kinase domain showed stability upon multiple freeze‐thaw cycles and exhibited significantly higher levels of tyrosine phosphorylation at pTyr525/Tyr526 in the Syk activation loop. Based on our data, we conclude that BEVS is the ideal host to produce an active and stable enzyme, which can be successfully employed for screening of Syk inhibitors in a high‐throughput system.
Siebengebirge – im Saum der Großlandschaften. Die Exkursion
Authors: Kremer Bruno P. 
Published: December 2009

AbstractDas rechtsrheinisch gegenüber Bonn gelegene Siebengebirge weist zwar nur eine Fläche von etwa 4800 ha auf, stellt aber als Landschaft ebenso wie als Naturraum ein recht ungewöhnliches Gefüge dar. Über kaum eine zweite Teillandschaft Deutschlands liegen vergleichbar zahlreiche Einzeluntersuchungen und Gesamtdarstellungen vor. Ein Exkursionsvorschlag entführt in diese faszinierende Teilregion am Ende des Unteren Mittelrheintals.
Gedanken‐Gang: Neue Ausstellung zum Gehirn im Weltkulturerbe Völklinger Hütte
Authors: Högermann Christiane 
Published: December 2009

AbstractIn der 1994 zum UNESCO‐Weltkulturerbe erklärten Völklinger Hütte lassen sich alle Phasen der Roheisenerzeugung an Originalschauplätzen nacherleben. Doch zunehmend treten auch multimediale Ausstellungsformen in den Vordergrund, so im 2004 eröffneten “Ferrodrom”, dem ersten Science‐Center im Saarland. Die Erzhalle der Völklinger Hütte ist das ideale Szenario für die spektakuläre Ausstellung “Dein Gehirn: denken, fühlen, handeln”.
Growth rates of small abdominal aortic aneurysms correlate with clinical events
Authors: Thompson A R , Cooper J A , Ashton H A , Hafez H 
Published: December 2009

Abstract

Background
This retrospective analysis of prospectively collected abdominal aortic aneurysm (AAA) screening data aimed to identify predictors of AAA-related events (surgery or death) with a view to better targeting of screening.

Methods
For the interval 1984–2007, data for 1649 subjects with an AAA were collected prospectively as part of the Chichester AAA screening programme. This included serial aortic size measurements, blood pressure, risk factors for arterial disease and concurrent medications. AAA growth rates were adjusted for risk factor confounders using flexible hierarchical modelling. AAA growth distribution was analysed using Silverman's test of multimodality.

Results
Some 1231 subjects met the inclusion criteria of having more than one scan and a surveillance interval of over 3 months. AAA growth showed a bimodal pattern with nearly 50 per cent of all aneurysms never progressing to surgery or rupture. Adjusted annual AAA growth rates of at least 2 mm significantly predicted AAA-related events.

Conclusion
This analysis identified a bimodal growth pattern for AAA, with a significant association between annual AAA growth rate of at least 2 mm and AAA-related events.