bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thick silica gel coatings on methylsilsesquioxane monoliths using anisotropic phase separation
Authors: Kanamori Kazuyoshi , Nakanishi Kazuki , Hanada Teiichi 
Published: October 2006

AbstractSilica gel coatings on methyltrimethoxysilane (MTMS)‐derived monoliths have been studied using wetting transition. Wetting transition is observed in a small confined space, where a coating solution phase‐separates into a well‐coarsened dimension, making all the phase‐separating polymerizing silica phase dynamically flow onto the existing surface of a mold. Bulk coating experiments have shown reductions of both macropore volume and diameter due to the coated layer. Comparing HPLC efficiencies of the coated monolith with those of the non‐coated MTMS monolith revealed that the retention factors drastically increased in both normal‐ and reversed‐phase modes. This is attributed to the existence of considerable amounts of accessible micropores left inside the coated layer, where analyte molecules travel and adsorb for a considerable period of time.
Pesticides analysis by liquid chromatography and capillary electrophoresis
Authors: Ravelo‐Pérez Lidia María , Hernández‐Borges Javier , Rodríguez‐Delgado Miguel Ángel 
Published: October 2006

AbstractNowadays, a wide range of pesticides are used in agricultural production, and their monitoring in samples of environmental and alimentary interest is of extreme importance to ensure, among others, the safety of consumption of foods. The aim of this work is to provide updated information about the major developments in CE and HPLC in pesticide analysis, covering relevant publications between 2004 and early 2006. The use of different sample pretreatment steps to provide a suitable extraction of these compounds from the different matrices as well as to increase the sensitivity of the determination is also discussed.
On‐line hyphenation of supercritical fluid extraction and two‐dimensional high performance liquid chromatography‐atmospheric pressure chemical ionization tandem mass spectrometer for the analysis of Ganoderma lucidum
Authors: Zhang Jie , Zhang Lihua , Duan Jicheng , Liang Zhen , Zhang Weibing , Huo Yushu , Zhang Yukui 
Published: October 2006

AbstractA novel on‐line system combining supercritical fluid extraction (SFE) and two‐dimensional high performance liquid chromatography (2D‐HPLC) was developed. A trap column and two three‐port valves were employed to couple SFE and 2D‐HPLC system, which was composed of a CN column and a monolithic silica column, connected by a 10‐port dual‐position valve. The analytes extracted by supercritical CO2 were completely transferred to the 2D‐HPLC system. After separation in two orthogonal modes, the eluents were delivered to APCI‐tandem‐MS for identification of the samples. In this way, sample preparation, separation, detection, and identification were integrated into an on‐line system permitting analysis of the fruiting bodies of Ganoderma lucidum, and at least 73 components in the extract were resolved with calculated peak capacity of up to 1643.
The co‐occurrence of posttraumatic stress disorder symptoms and pain: Is depression a mediator?
Authors: Poundja Joaquin , Fikretoglu Deniz , Brunet Alain 
Published: October 2006

AbstractAlthough recent studies suggest that posttraumatic stress disorder (PTSD) symptoms and pain may be related, the possible mediational role of depression in this relationship has not been examined. This study sought to examine this question in a sample of 130 male veterans seeking assessment or treatment for deployment‐related PTSD. Results suggest that PTSD and pain are moderately related (r = .29) but that this relationship is fully mediated by depression. Our findings have important clinical implications: Treatment of PTSD and pain in veteran populations should include careful assessment and regular monitoring of depression.
Gelchromatographische Abtrennung und Nachweis hochpolymerer Zusätze in Vaselinen 11. Mitteilung: Über den Einfluß chemischer und physikalischer Meßdaten auf die Gebrauchseigenschaften von Vaseline
Authors: Langmaack H.‐J. , Sucker H. 
Published: October 2006

AbstractHochpolymere Substanzen aus Vaselinen oder ähnlichen Kohlenwasserstoffgemischen, wie z. B. Schmieröle, können durch Gelfiltration abgetrennt und infrarotspektroskopisch und gelchromatographisch identifiziert werden.
Metathesis of Unsaturated Fatty Esters
Authors: Verkuijlen E. , Boelhouwer C. 
Published: October 2006

AbstractThe development of a homogeneous catalyst [WCl6/Sn(CH3)4) for the metathesis of unsaturated fatty esters encloses new routes in fat chemistry. By these reactions an exchange of alkylidene moities takes place, thus methyl oleate is converted into 9‐octadecene and 9‐octadecenedioic dimethyl ester. The metathesis of poly‐unsaturated esters leads to a much larger number of products, namely polyenes, mono‐ and dicarboxylic esters, and cyclopolyenes. Specially the formation of 1,4‐cyclohexadiene is of great interest. The metathesis of unsaturated fatty oils and the cometathesis with alkenes are also possible. Reactants of technical purity with a low acid value (<0.1) can undergo metathesis. The reaction is essentially thermoneutral; the distribution of products is statistical and no completion of the reaction occurs in one way or an other. Thus separation of reaction products and unconverted material is necessary. By the metathesis of mono‐unsaturated esters this can be done by fractional crystallization. A review is given of these and other applications on account of the latest research development.
Gelchromatographische Abtrennung und Nachweis hochpolymerer Zusätze in Vaselinen 11. Mitteilung: Über den Einfluß chemischer und physikalischer Meßdaten auf die Gebrauchseigenschaften von Vaseline
Authors: Langmaack H.‐J. , Sucker H. 
Published: October 2006

AbstractHochpolymere Substanzen aus Vaselinen oder ähnlichen Kohlenwasserstoffgemischen, wie z. B. Schmieröle, können durch Gelfiltration abgetrennt und infrarotspektroskopisch und gel‐chromatographisch identifiziert werden.
Phosphatfreie Wasch‐ und Reinigungsmittel
Authors: Niederstebruch A. 
Published: October 2006

AbstractDie in neuester Zeit aus der Patentliteratur bekannt gewordenen phosphatfreien Wasch‐ und Reinigungsmittel lassen sich in zwei Gruppen einordnen. Die erste umfaßt solche, die weder Phosphate noch deren Ersatzstoffe betreffen. Die vergleichsweise gute Reinigungswirkung dieser Mittel wird durch den Einsatz solcher Tenside erzielt, die im Vergleich zu bisher üblichen eine größere Anzahl von polaren Gruppen enthalten. Beispiele hier‐für werden genannt. Die zweite Gruppe betrifft Phosphatersatz‐stoffe, insbesondere niedermolekulare anorganische bzw. organische Verbindungen, höhermolekulare wasserlösliche organische Verbindungen und anorganische sowie organische Ionenaustauscher. Auch hierfür werden Beispiele genannt. Die Reinigungskraft insbesondere tripolyphosphathaltiger Waschmittel wird solchen ohne Phosphatanteile gegenübergestellt.
Bestimmung reduzierender Substanzen in Glycerin mit Hilfe einer Transmissionsmessung
Authors: Bölsche U. 
Published: October 2006

AbstractDie Untersuchung von Reinglycerin beinhaltet eine Bestimmung der reduzierenden Substanzen. Es existiert eine Reihe von verschiedenen Grenzwertbestimmungen, die in nationalen und internationalen Normen und Arzneibüchern beschrieben werden. Dabei wird nach einer Umsetzung mit entsprechenden Reagenzien eine evtl. auftretende Färbung und/oder Trübung visuell beurteilt. Nachteilig hierbei sind die Subjektivität der Auswertung und die Vielzahl der Verfahren. Eine Methode ist entwickelt worden, die sowohl eine objektive Messung (Lichtdurchlässigkeit) erlaubt als auch als Universaltest angewendet werden kann. Das Meßergebnis dieses Tests kann mit dem Resultat der Analyse einer beliebigen Standardmethode korreliert werden. Die Anwendung mehrerer Bestimmungsmethoden ist somit nicht mehr erforderlich. Neben der Möglichkeit, eine Abstufung der Glycerinqualität durchzuführen, können wichtige Kriterien von Standardmethoden, wie z. B. Wiederholbarkeit, Empfindlichkeit etc., mit Hilfe der Transmissionsmessung zuverlässig überprüft werden.
Glucosinolates in Embryo, Cotyledon and Callus Cultures of Rape Depending on External Factors
Authors: Rogozińska J. , Drozdowska L. 
Published: October 2006

AbstractThe influence of light, temperature, sulphur and nitrogen as well as growth substance combinations were tested on glucosinolate content in embryo, cotyledon and callus culture of rape. It was found, that depending on these factors, the glucosinolate breakdown varied, and in most cases the 2‐week‐old cultures did not contain those compounds. Also in plantlets, which differentiated from the cotyledons and remained in the in vitro culture, as well as in the callus, the glucosinolates were not detected.
Mutations in LRRK2 other than G2019S are rare in a north american–based sample of familial Parkinson's disease
Authors: Pankratz Nathan , Pauciulo Michael W. , Elsaesser Veronika E. , Marek Diane K. , Halter Cheryl A. , Rudolph Alice , Shults Clifford W. , Foroud Tatiana , Nichols William C. 
Published: October 2006

AbstractA total of 956 individuals with Parkinson's disease (PD) from 430 multiplex PD pedigrees were screened for 12 previously reported, pathogenic LRRK2 mutations: R793M, L1114L, I1371V, R1441C, R1441G, R1441H, Y1699C, M1869T, I2012T, I2020T, G2385R, and IVS31 +3G>A. Previous screening identified the LRRK2 G2019S mutation in 5% of our families. Only 1 of the 12 newly screened mutations, R1441C, was detected in a single family in our patient cohort. These results indicate that, although the G2019S mutation remains the most common mutation identified in familial PD patients, other mutations in LRRK2 are infrequent. © 2006 Movement Disorder Society
Computerized posturography balance assessment of patients with bilateral ventralis intermedius nuclei deep brain stimulation
Authors: Ondo William G. , Almaguer Mike , Cohen Helen 
Published: October 2006

AbstractBilateral ventralis intermedius nuclei (Vim) deep brain stimulation (DBS) improves tremor in patients with both essential tremor (ET) and Parkinson's disease (PD). In each condition, patients have individually noted both subjective improvement and worsening in balance. Computerized posturography (CP) is able to quantify some aspects of balance. Twenty‐one patients (8 with PD and 13 with ET) with bilateral Vim DBS were recruited to undergo randomized‐order identical CP testing (EquiTest system) while their DBS devices were both activated and deactivated. One PD patient could not complete any OFF assessment and is not included. Three PD patients could not tolerate portions of the OFF testing. Overall, sensory organization testing was improved by DBS activation in conditions that involved quiet standing with eyes open with no motion of the support surface, or with sway‐referenced support surface motion, but worsened during quiet standing with eyes closed only in ET patients. Falls lessened with activation in ET patients. Motor control testing was not changed. Bilateral Vim DBS activation mostly improved balance, but may modestly worsen other specific features. © 2006 Movement Disorder Society
Quantitative MRI of cartilage and bone: degenerative changes in osteoarthritis
Authors: Eckstein Felix , Burstein Deborah , Link Thomas M. 
Published: October 2006

AbstractMagnetic resonance imaging (MRI) and quantitative image analysis technology has recently started to generate a great wealth of quantitative information on articular cartilage and bone physiology, pathophysiology and degenerative changes in osteoarthritis. This paper reviews semiquantitative scoring of changes of articular tissues (e.g. WORMS = whole‐organ MRI scoring or KOSS = knee osteoarthritis scoring system), quantification of cartilage morphology (e.g. volume and thickness), quantitative measurements of cartilage composition (e.g. T2, T1rho, T1Gd = dGEMRIC index) and quantitative measurement of bone structure (e.g. app. BV/TV, app. TbTh, app. Tb.N, app. Tb.Sp) in osteoarthritis. For each of these fields we describe the hardware and MRI sequences available, the image analysis systems and techniques used to derive semiquantitative and quantitative parameters, the technical accuracy and precision of the measurements reported to date and current results from cross‐sectional and longitudinal studies in osteoarthritis. Moreover, the paper summarizes studies that have compared MRI‐based measurements with radiography and discusses future perspectives of quantitative MRI in osteoarthritis. In summary, the above methodologies show great promise for elucidating the pathophysiology of various tissues and identifying risk factors of osteoarthritis, for developing structure modifying drugs (DMOADs) and for combating osteoarthritis with new and better therapy. Copyright © 2006 John Wiley & Sons, Ltd.
Dynamic MRS and MRI of skeletal muscle function and biomechanics
Authors: Prompers Jeanine J. , Jeneson Jeroen A. L. , Drost Maarten R. , Oomens Cees C. W. , Strijkers Gustav J. , Nicolay Klaas 
Published: October 2006

AbstractMR is a powerful technique for studying the biomechanical and functional properties of skeletal muscle in vivo in health and disease. This review focuses on 31P, 1H and 13C MR spectroscopy for assessment of the dynamics of muscle metabolism and on dynamic 1H MRI methods for non‐invasive measurement of the biomechanical and functional properties of skeletal muscle. The information thus obtained ranges from the microscopic level of the metabolism of the myocyte to the macroscopic level of the contractile function of muscle complexes. The MR technology presented plays a vital role in achieving a better understanding of many basic aspects of muscle function, including the regulation of mitochondrial activity and the intricate interplay between muscle fiber organization and contractile function. In addition, these tools are increasingly being employed to establish novel diagnostic procedures as well as to monitor the effects of therapeutic and lifestyle interventions for muscle disorders that have an increasing impact in modern society. Copyright © 2006 John Wiley & Sons, Ltd.
Role of proton MR for the study of muscle lipid metabolism
Authors: Boesch Chris , Machann Juergen , Vermathen Peter , Schick Fritz 
Published: October 2006

Abstract1H‐MR spectroscopy (MRS) of intramyocellular lipids (IMCL) became particularly important when it was recognized that IMCL levels are related to insulin sensitivity. While this relation is rather complex and depends on the training status of the subjects, various other influences such as exercise and diet also influence IMCL concentrations. This may open insight into many metabolic interactions; however, it also requires careful planning of studies in order to control all these confounding influences. This review summarizes various historical, methodological, and practical aspects of 1H‐MR spectroscopy (MRS) of muscular lipids. That includes a differentiation of bulk magnetic susceptibility effects and residual dipolar coupling that can both be observed in MRS of skeletal muscle, yet affecting different metabolites in a specific way. Fitting of the intra‐ (IMCL) and extramyocellular (EMCL) signals with complex line shapes and the transformation into absolute concentrations is discussed. Since the determination of IMCL in muscle groups with oblique fiber orientation or in obese subjects is still difficult, potential improvement with high‐resolution spectroscopic imaging or at higher field strength is considered. Fat selective imaging is presented as a possible alternative to MRS and the potential of multinuclear MRS is discussed. 1H‐MRS of muscle lipids allows non‐invasive and repeated studies of muscle metabolism that lead to highly relevant findings in clinics and patho‐physiology. Copyright © 2006 John Wiley & Sons, Ltd.
Topology optimization of acoustic–structure interaction problems using a mixed finite element formulation
Authors: Yoon Gil Ho , Jensen Jakob Søndergaard , Sigmund Ole 
Published: October 2006

AbstractThe paper presents a gradient‐based topology optimization formulation that allows to solve acoustic–structure (vibro‐acoustic) interaction problems without explicit boundary interface representation. In acoustic–structure interaction problems, the pressure and displacement fields are governed by Helmholtz equation and the elasticity equation, respectively. Normally, the two separate fields are coupled by surface‐coupling integrals, however, such a formulation does not allow for free material re‐distribution in connection with topology optimization schemes since the boundaries are not explicitly given during the optimization process. In this paper we circumvent the explicit boundary representation by using a mixed finite element formulation with displacements and pressure as primary variables (a u/p‐formulation). The Helmholtz equation is obtained as a special case of the mixed formulation for the elastic shear modulus equating to zero. Hence, by spatial variation of the mass density, shear and bulk moduli we are able to solve the coupled problem by the mixed formulation. Using this modelling approach, the topology optimization procedure is simply implemented as a standard density approach. Several two‐dimensional acoustic–structure problems are optimized in order to verify the proposed method. Copyright © 2006 John Wiley & Sons, Ltd.
Plastic and fracture behavior of nanosilica‐filled poly(methyl methacrylate)
Authors: Muriel Muriel , Dubault André , Halary Jean Louis 
Published: October 2006

AbstractThe plastic and fracture behavior of ‘model’ hybrid materials based on methyl methacrylate and methacryloxypropyl‐grafted nanosilica was investigated. A four‐step synthesis procedure allowed preparation of transparent nanosilica–poly(methyl methacrylate) networks of well‐defined architecture, of variable particle diameter, volume fraction of particles, number of methacryloyl units grafted per surface unit of silica particles and nature of the grafting agent. Plasticity behavior was investigated through compression tests. The evolution of yield stress with volume fraction of fillers can be understood by taking into account the undeformability of particles and using the geometrical Kerner approach. The reduction of plastic flow plateau by a substantial strain hardening was imputed to the presence of crosslinks on the particles. Fracture properties were deduced from three‐point bending experiments on notched samples. The effects on toughness of filler incorporation are tentatively related to plasticity and to the presence of crosslinks. Copyright © 2006 Society of Chemical Industry
Blood protein adsorption onto macroporous semi‐interpenetrating polymer networks (IPNs) of poly(ethylene glycol) (PEG) and poly(2‐hydroxyethyl methacrylate) (PHEMA) and assessment of in vitro blood compatibility
Authors: Bajpai Anil K 
Published: October 2006

AbstractThis work reports a study of the adsorption of fibrinogen (Fgn) onto the surface of semi‐interpenetrating polymer networks (IPNs) of poly(ethylene glycol) (PEG) and poly(2‐hydroxyethyl methacrylate) (PHEMA). The semi‐IPNs were prepared by polymerizing 2‐hydroxyethyl methacrylate with a redox system and in the presence of PEG and crosslinker ethyleneglycol dimethacrylate. The proposed spongy IPNs were characterized by Fourier transform infrared and environmental scanning electron microscopy methods, and network structural parameters, such as molecular weight between crosslinks and crosslink density, were calculated using swelling measurements. The adsorption of Fgn was carried out onto the spongy IPNs and kinetic constants of the adsorption process as well as isotherm constants were evaluated. The adsorption process was also studied under varying pH, ionic strengths, and chemical architecture of the IPNs. The anti‐thrombogenic behaviour of the polymer matrices was judged using in vitro tests. Copyright © 2006 Society of Chemical Industry
Optimized synthesis of carrageenan‐ graft‐poly(sodium acrylate) superabsorbent hydrogel using the Taguchi method and investigation of its metal ion absorption
Authors: Pourjavadi Ali , Amini‐Fazl Mohammad Sadegh 
Published: October 2006

AbstractThe Taguchi method, a robust experimental design, was used for the optimization of the synthesis of a novel biopolymer‐based superabsorbent hydrogel, carrageenan‐graft‐poly(sodium acrylate). The Taguchi method was applied for the experiment and standard 16 orthogonal arrays with five factors and four levels for each factor were used. In the synthesis of the superabsorbent hydrogel, N,N′‐methylene bisacrylamide (MBA) was used as crosslinker, ammonium persulfate as initiator, and acrylic acid as monomer. Neutralization percent and reaction temperature were used as important factors. The analysis of variance results showed that the most important factor in this synthesis was MBA concentration. Under the optimized conditions determined, the maximum capacity of swelling in distilled water was found to be 1383 (g (g dried gel)−1). Furthermore, the absorption capacity of the hydrogel towards bivalent metal ions was evaluated. The hydrogel may be considered as a candidate to develop an efficient absorbent biopolymer in water treatment applications. Copyright © 2006 Society of Chemical Industry
Spectroscopic study of conformational changes accompanying self‐assembly of HCV core protein
Authors: Rodríguez‐Casado Arantxa , Molina Marina , Carmona Pedro 
Published: October 2006

AbstractElectron microscopy and infrared and Raman spectroscopy have been used here to study the morphology, size distribution, secondary and tertiary structures of protein particles assembled from a truncated hepatitis C virus (HCV) core protein covering the first 120 aa. Particles of pure protein, having similar morphology and size distribution of those of nucleocapsids found in sera from HCV‐infected patients, have been visualized for the first time. The secondary structure of these protein particles involve β‐sheet enrichment in relation to its protein monomer. Tertiary/quaternary structure has also been studied using the dynamics of H/D exchange. With this aim infrared spectra were measured as a function of H/D exchange time and subsequently analyzed by principal component analysis and two‐dimensional correlation spectroscopy. Temporal dynamics of exchange for these protein particles were as follows: arginine residues exchanged first, followed by turn and unordered structures, followed by β‐sheets which may act as linkers of protein monomers. Proteins 2007. © 2006 Wiley‐Liss, Inc.