bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mathematical Modeling of the Grafting of Maleic Anhydride onto Polypropylene
Authors: Giudici Reinaldo 
Published: December 2007

AbstractSummary: A kinetic model for the free radical grafting of maleic anhydride (MAH) onto polypropylene (PP) was developed. The model is able to predict the effect of MAH and initiator concentrations on the grafting degree as well as the changes in the polymer molecular weight distribution during the grafting process. Simulation results are validated by comparison with data from different sources, showing that the model is able to represent reasonably the main trends of the experimentally measured variables both in batch (internal mixer, static film) and in continuous processing (twin‐screw extruder), under different conditions. Model predictions are also compared well with a Monte Carlo simulation previously presented in the literature for the same process.
RAFT Polymerization ‐ Investigation of the Initialization Period and Determination of the Transfer Coefficients
Authors: Drache Marco , Schmidt‐Naake Gudrun 
Published: December 2007

AbstractSummary: The rate of activation of the initial RAFT agent is very important with regard to effective control of the polymerization. The initialization period of Benzyl Dithiobenzoate RAFT mediated bulk polymerization of styrene at 120 °C was investigated at different RAFT agent and initiator concentrations. The concentration of the RAFT agent and the monomer concentration in the initial phase of the RAFT polymerization were determined experimentally by Size Exclusion Chromatography (SEC). We characterized the RAFT initialization following the concept of Rizzardo et al.1,2 by determination of the transfer coefficients. For the determination of the transfer coefficients from the experimental data a Monte Carlo simulation was developed by us.
Molecular Weight Control in Emulsion Polymerization by Catalytic Chain Transfer: A Reaction Engineering Approach
Authors: Smeets Niels M.B. , Meda Ujwal S. , Heuts Johan P.A. , Keurentjes Jos T.F. , van Herk Alex M. , Meuldijk Jan 
Published: December 2007

AbstractSummary: For the application of catalytic chain transfer in (mini)emulsion polymerization, catalyst partitioning and deactivation are key parameters that govern the actual catalyst concentration at the locus of polymerization and consequently the final molecular weight distribution. A global model, based on the Mayo equation, catalyst partitioning and deactivation was developed. The influence of several reaction parameters on the instantaneous number average molecular weight was quantified.
Analysis of Nitroxide‐Mediated Polymerization of Styrene by Soft‐Ionization‐MS – A Challenging Task
Authors: Dempwolf Wibke , Flakus Silke , Schmidt‐Naake Gudrun 
Published: December 2007

AbstractSummary: A suitable method to synthesize well defined polymers with different architectures is the application of functionalized alkoxyamines in the controlled radical polymerization. The analysis of such nitroxide capped polymers by MALDI‐ TOF‐MS is complex. Unexpected results of the mass analysis of our polymers lead us to study the influence of the structure of the analyte and the experimental conditions of the measurements in detail. In addition to common nitroxides like TEMPO, TEMPO‐derivates, TIPNO and BIPNO, other alkoxyamines with special structure requirements were synthesized. These alkoxyamines were tested in different MALDI experiments. Supported by a comparison with other methods we postulate a fragmentation mechanism inside the nitroxide‐group which takes place during the MALDI measurement. To the best of our knowledge such a fragmentation of the nitroxide‐group itself during a MALDI‐TOF experiment has not been described before.
Participation of the subthalamic nucleus in executive functions: An intracerebral recording study
Authors: Baláž Marek , Rektor Ivan , Pulkrábek Jiří 
Published: December 2007

AbstractThe objective of our work was to find whether the subthalamic nucleus (STN) is directly involved in cognitive activities, specifically in executive functions. Ten patients with idiopathic Parkinson's disease had P3 potentials recorded by externalized deep brain electrodes that were implanted in the STN or in its immediate vicinity. Two contacts of each electrode were positioned inside the STN according to clinical effect, perioperative microrecording, and stimulation. The P3 waves were recorded following the auditory stimulus in a standard oddball paradigm. They were compared with the P3 waves elicited from a protocol modified by a dual task with an increased demand on executive functions. The P3 potentials with a steep amplitude gradient evoked by the modified protocol were detected by the contacts in 8 of the 14 available electrodes, located either inside the STN or in its immediate vicinity. The modified protocol led to an increased latency of the P3 potential in 8 of 14 electrodes. No local field potentials of the standard P3 potentials were recorded. The P3 potentials related to the increased demand on executive functions were detected by the STN contacts known to have the best effect on Parkinsonian motor signs. This could suggest that the STN takes part in the executive function processing. © 2007 Movement Disorder Society
Validity of spiral analysis in early Parkinson's disease
Authors: Saunders‐Pullman Rachel , Derby Carol , Stanley Kaili , Floyd Alicia , Bressman Susan , Lipton Richard B. , Deligtisch Amanda , Severt Lawrence , Yu Qiping , Kurtis Mónica , Pullman Seth L. 
Published: December 2007

AbstractSpiral analysis is an objective, easy to administer noninvasive test that has been proposed to measure motor dysfunction in Parkinson disease (PD). We compared overall Unified Parkinson Disease Rating Scale Part III scores to selected indices derived from spiral analysis in seventy‐four patients with early PD (mean duration of disease 2.4 ± 1.7 years, mean age 61.5 ± 9.7 years). Of the spiral indices, degree of severity, first order zero crossing, second order smoothness, and mean speed were best correlated with total motor Unified Parkinson's Disease Rating Scale (UPDRS) score (all P < 0.01), and these indices showed a gradient across worsening tertiles of UPDRS (P < 0.05). Spiral indices also correlated with UPDRS ratings for the worst side and worst arm scores as well. The domains of bradykinesia, rigidity, and action tremor were correlated with first order crossing, second order smoothness, and mean speed, where as rest tremor was most highly correlated with degree of severity. This suggests that the spiral analysis may supplement motor assessment in PD, although further analysis of spiral metrics, a larger sample and longitudinal data should be evaluated. © 2007 Movement Disorder Society
A search game taking account of attributes of searching resources
Authors: Hohzaki Ryusuke 
Published: December 2007

AbstractThis article deals with a two‐person zero‐sum game called a search allocation game (SAG), in which a searcher and a target participate as players. The searcher distributes his searching resources in a search space to detect the target. The effect of resources lasts a certain period of time and extends to some areas at a distance from the resources' dropped points. On the other hand, the target moves around in the search space to evade the searcher. In the history of search games, there has been little research covering the durability and reachability of searching resources. This article proposes two linear programming formulations to solve the SAG with durable and reachable resources, and at the same time provide an optimal strategy of distributing searching resources for the searcher and an optimal moving strategy for the target. Using examples, we will analyze the influences of two attributes of resources on optimal strategies. © 2007 Wiley Periodicals, Inc. Naval Research Logistics 2008
Bilinear finite elements for shells: Isoparametric quadrilaterals
Authors: Niemi Antti H. , Pitkäranta Juhani 
Published: December 2007

AbstractWe study the accuracy and reliability of the lowest‐order bilinear shell finite element schemes. Our approach is based mainly on a simplified shallow shell model analogous to the Reissner–Mindlin model of plate bending. The numerical models are constructed by modifying the strain expressions within the usual energy principle so that error analysis in the energy norm framework is possible. Our theoretical predictions supported by numerical experiments indicate that the performance of the low‐order methods is both mesh and case dependent. Copyright © 2007 John Wiley & Sons, Ltd.
The enriched space–time finite element method (EST) for simultaneous solution of fluid–structure interaction
Authors: Zilian A. , Legay A. 
Published: December 2007

AbstractThe paper introduces a weighted residual‐based approach for the numerical investigation of the interaction of fluid flow and thin flexible structures. The presented method enables one to treat strongly coupled systems involving large structural motion and deformation of multiple‐flow‐immersed solid objects.The fluid flow is described by the incompressible Navier–Stokes equations. The current configuration of the thin structure of linear elastic material with non‐linear kinematics is mapped to the flow using the zero iso‐contour of an updated level set function. The formulation of fluid, structure and coupling conditions uniformly uses velocities as unknowns. The integration of the weak form is performed on a space–time finite element discretization of the domain. Interfacial constraints of the multi‐field problem are ensured by distributed Lagrange multipliers. The proposed formulation and discretization techniques lead to a monolithic algebraic system, well suited for strongly coupled fluid–structure systems. Embedding a thin structure into a flow results in non‐smooth fields for the fluid. Based on the concept of the extended finite element method, the space–time approximations of fluid pressure and velocity are properly enriched to capture weakly and strongly discontinuous solutions. This leads to the present enriched space–time (EST) method. Numerical examples of fluid–structure interaction show the eligibility of the developed numerical approach in order to describe the behavior of such coupled systems. The test cases demonstrate the application of the proposed technique to problems where mesh moving strategies often fail. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of molecular weight and degree of deacetylation on controlled release of isoniazid from chitosan microspheres
Authors: Gupta K. C. , Jabrail F. H. 
Published: December 2007

AbstractGlutaraldehyde cross‐linked chitosan microspheres for controlled release of isoniazid were prepared using chitosan of different molecular weights (MWs) and degrees of deacetylation (DDAs). Chitosan microspheres were characterized for their size, hydrophobocity, degree of swelling and loading of isoniazid. Hydrophobicity of chitosan microspheres increased on increasing the degree of cross‐linking and MW of chitosan. Chitosan microspheres with high degree of deacetylation (DDA) (75 wt%), high MW chitosan (2227 kg mol−1), and with 12 wt% concentration of glutaraldehyde showed optimum loading and release of isoniazid. The isoniazid from chitosan microspheres was released in two steps, i.e. burst (%RB) and controlled (%RC) steps. The microspheres with low MW chitosan (260 kg mol−1) and low DDA (48 wt%) showed prominent burst release of isoniazid, but microspheres with high MW chitosan (2227 kg mol−1) and high DDA (75 wt%) have released more isoniazid in a controlled manner (60 wt%) at 37°C in a solution of pH 5.0 ± 0.1. The burst step of drug release (%RB) has followed first order kinetics, whereas controlled step of drug release (%RC) followed zero order kinetics. The burst step of drug release was Fickian and controlled step was non‐Fickian in nature. The diffusion constant (D) for isoniazid release was influenced by the properties of chitosan and degree of cross‐linking. Copyright © 2007 John Wiley & Sons, Ltd.
Ceric Ammonium Nitrate Initiated Grafting of PEG to Plasma Polymers for Cell‐Resistant Surfaces
Authors: Vickers Naomi J. , McArthur Sally L. , Shard Alex G. , MacNeil Sheila 
Published: December 2007

AbstractThe development of a facile method with general applicability and mild reaction conditions for grafting PEG onto surfaces to reduce bio‐adhesion is described. The approach taken was to use CAN to graft PEG to plasma polymers coatings selected to give a high concentration of alcohol groups. The study showed that grafting required functional groups on surfaces, a minimum concentration of CAN initiator (0.05 M) and was time and initiator concentration dependent. Adhesion of fibroblasts and endothelial cells was reduced to negligible levels compared to the adhesion to tissue culture polystyrene and untreated plasma polymers of allyl alcohol following CAN induced PEG grafting.magnified image
Fluorine‐Based Plasma Treatment of Biocompatible Silicone Elastomer: The Effect of Temperature on Etch Rate and Surface Properties
Authors: Szmigiel Dariusz , Hibert Cyrille , Bertsch Arnaud , Pamuła Elżbieta , Domański Krzysztof , Grabiec Piotr , Prokaryn Piotr , Ścisłowska‐Czarnecka Anna , Płytycz Barbara 
Published: December 2007

AbstractThis paper describes F‐based dry etching and resulting surface properties of biocompatible silicone elastomer. The etch rate of polysiloxane and surface morphology was found to be highly temperature dependent. An increase in temperature results in a significantly higher etch rate and a lower surface roughness. Possible mechanisms of the etching process and the roughness formation on an elastomer surface are discussed. The polysiloxane surface was proved to have hydrophobic characteristics both prior to and after plasma exposure. The results of the preliminary cytotoxicity study are very promising: cell viability on a raw and plasma treated polysiloxane was found to be very high and comparable to control. Due to the acceptable etch rate and absence of toxic contaminations, a F‐containing plasma is considered an excellent method for microprocessing of silicone elastomers intended for biomedical applications.magnified image
Towards a comprehensive proteome of normal and malignant human colon tissue by 2‐D‐LC‐ESI‐MS and 2‐DE proteomics and identification of S100A12 as potential cancer biomarker
Authors: Thierolf Michael , Hagmann Marie‐Luise , Pfeffer Michael , Berntenis Nikolaos , Wild Norbert , Roeßler Markus , Palme Stefan , Karl Johann , Bodenmüller Heinz , Rüschoff Josef , Rossol Siegbert , Rohr Gerhard , Rösch Wolfgang , Friess Helmut , Eickhoff Axel , Jauch Karl‐Walter , Langen Hanno , Zolg Werner , Tacke Michael 
Published: December 2007

AbstractThe aim of this study was to characterize the proteome of normal and malignant colonic tissue. We previously studied the colon proteome using 2‐DE and MALDI‐MS and identified 734 proteins (Roeßler, M., Rollinger, W., Palme S., Hagmann, M.‐L., et al.., Clin. Cancer Res. 2005, 11, 6550–6557). Here we report the identification of additional colon proteins from the same set of tissue samples using a complementary nano‐flow 2‐D‐LC‐ESI‐MS. In total, 484 proteins were identified in colon. Of these, 252 had also been identified by the 2‐DE/MALDI‐MS approach, whereas 232 proteins were unique to the 2‐D‐LC‐ESI‐MS analysis. Comparing protein expression in neoplastic and normal colon tissue indicated elevated expression of several proteins in colorectal cancer, among them the well established tumor marker carcinoembryonic antigen, as well as calnexin, 40S ribosomal protein S15a, serpin H1, and S100A12. Overexpression of these proteins was confirmed by immunoblotting. Serum levels of S100A12 were determined by ELISA and were found to be strongly elevated in colorectal cancer patients compared to healthy individuals. We conclude, that 2‐D‐LC‐ESI‐MS is a powerful approach to identify and compare protein profiles of tissue samples, that it is complementary to 2‐DE/MALDI‐MS approaches and has the potential to identify novel biomarkers.
Identification of circulating endorepellin LG3 fragment: Potential use as a serological biomarker for breast cancer
Authors: Chang Jong Wook , Kang Un‐Beom , Kim Dong Hyun , Yi Jae Kyo , Lee Jong Won , Noh Dong‐Young , Lee Cheolju , Yu Myeong‐Hee 
Published: December 2007

AbstractComparative proteome analysis was performed on the cultured media of human nontumor and malignant breast cell lines, Hs578Bst and Hs578T, respectively, in search of a serological biomarker(s) for breast cancer. Proteins in the conditioned media were separated by 2‐D PAGE and then visualized by silver‐staining. Eight proteins changed differentially by more than two‐fold were identified by MALDI‐TOF/TOF MS. Among the proteins identified, the terminal laminin‐like globular (LG3) domain of endorepellin, which was recently reported as an antiangiogenesis factor, was decreased in the cancer cell line. We confirmed the bone morphogenic protein‐1 (BMP‐1) mediated cleavage site on the N‐terminus of endorepellin LG3 fragment. This finding suggests that the LG3 fragment is specifically released by a BMP‐1 driven limited proteolytic process. The protein was also detected in plasma by Western blot analysis and selected reaction monitoring (SRM). The plasma level of the endorepellin LG3 fragment was significantly lower in breast cancer patients compared to healthy donors (p = 0.017; n = 12). The LG3 protein concentration in the control plasma was measured at approximately 3.7 pmol/mL compared to 1.8 pmol/mL in plasma from the cancer patients. We suggest that these results support the potential use of the endorepellin LG3 fragment as a new serological biomarker for breast cancer.
Secretome analysis of novel IgE‐binding proteins from Penicillium citrinum
Authors: Chiu Li‐Li , Lee Kuang‐Lun , Lin Yu‐Fen , Chu Chia‐Yu , Su Son‐Nan , Chow Lu‐Ping 
Published: December 2007

AbstractThe Penicillium genus of fungi is a frequently reported cause of allergic reactions. However, only a limited number of allergens have been reported. In Penicillium spp., many allergens show higher IgE‐binding activity in culture filtrate extracts than in cellular extracts. In order to investigate the IgE‐reactive profile of mold‐sensitized patients, secreted IgE‐reactive proteins from Penicillium citrinum were identified by 2‐DE, serum immunoblotting, and nanoLC‐MS/MS. Among the IgE‐reactive spots, one known allergen, Pen c 13, and four novel allergens were identified. The cDNAs coding for Pen c 32 and Pen c 30 were cloned using designed primers based on nanoLC‐MS/MS analysis. The amino acid sequences of Pen c 32 and Pen c 30 were, respectively, found to have extensive similarity with those of pectate lyases and catalases from various fungi. Native Pen c 30 was shown to have catalase activity and to bind to serum IgE from 48% of mold‐allergic patients and induced immediate type skin reactions in a sensitized patient. Here, we present a proteome approach which resulted in the identification of four novel secreted allergens. These novel allergens might be useful in allergy diagnosis and in the treatment of mold‐allergic disorders.
Stable and unstable angina: Identifying novel markers on circulating leukocytes
Authors: Brown Angus , Lattimore Jo‐Dee , McGrady Michele , Sullivan David , Dyer Wayne , Braet Filip , dos Remedios Cristobal 
Published: December 2007

AbstractThere is currently no blood‐based test that can rapidly and objectively distinguish between chest pain which is initiated by increased myocardial oxygen demand (stable angina pectoris (SAP)) and chest pain initiated due to decreased coronary blood flow (unstable angina pectoris (UAP)). Since leukocytes play an active role in the progression of coronary artery disease (CAD), we hypothesize these can provide novel markers of SAP and UAP. Here we use a microarray of 82 cluster of differentiation (CD) antibodies (plus controls) to selectively immobilize peripheral blood mononuclear cells. We find that the pattern of leukocyte immobilization from patients with CAD significantly differs from healthy donors. Within the CAD group, 15 SAP patients exhibited significant (p<0.05) changes in 8 of 82 CD antibody spots compared to 19 age‐matched healthy blood donors. An additional ten CD antigens differed between healthy donors and patients with UAP (p<0.05). Furthermore, seven CD antibody spots are significantly different between SAP and UAP patients. These preliminary data suggest it is now appropriate to undertake a larger clinical trial to test the hypothesis that these antibody microarrays can monitor the progression from SAP to UAP.
Breast Cancer and Proteomics: The inaugural Mammary Gland Proteome Initiative (MGPI) workshop 12–13 July 2007, Cambridge, UK
Authors: Souchelnytskyi Serhiy , Alldridge Louise 
Published: December 2007

AbstractBreast cancer proteomics has progressed to a level where further development requires the coordination and cooperation of research strategies and resources. The Mammary Gland Proteome Initiative (MGPI) aims to provide a platform to promote such a coordination of comprehensive studies of mammary glands in health and disease. An inaugural MGPI workshop, Breast Cancer and Proteomics, was held in Cambridge, UK in July 2007. The workshop outlined the development of the MGPI, with emphasis on four specific programs: (i) breast cancer, (ii) standardisation, deposition and processing of data, (iii) technology and (iv) logistics.
Theoretical Analysis of Plasma Enhancement of Propellant Burning Rate
Authors: Alimi Roger , Berdichevsky Vadim 
Published: December 2007

AbstractA theoretical model of the combustion of a nitramine solid propellant in the presence of a plasma jet is proposed. Unlike standard double‐base compositions, nitramine propellants exhibit experimental evidence that plasma induces a burning rate enhancement. The model is based on heat transfer considerations and proposes a closed‐form solution of the enhancement of the propellant burning rate as a function of the thermophysical parameters of the system. The model provides a good qualitative agreement with experimental results.
Sb6O13 and Bi2O3 as Oxidants for Si in Pyrotechnic Time Delay Compositions
Authors: Kalombo Lonji , Del Fabbro Olinto , Conradie Corrie , Focke Walter W. 
Published: December 2007

AbstractLead and its compounds in detonator time delays are being phased out owing to environmental and health concerns. It was found that changing from the conventional rolled lead elements to rigid aluminium tubes caused a significant decrease in the burn rate. It also impaired ignitability, especially of slow burning compositions such as SiBaSO4. Consequently, potential alternatives for the latter and also the fast burning SiPb3O4 system were sought. Bi2O3, prepared by thermal decomposition of bismuth subcarbonate, gave fast burning compositions with silicon as fuel (155 mm s−1 with 20% Si). This system was ignitable by the spit of a shock tube. The SiSb6O13 system required an initiating composition and yielded slow burning compositions. The lowest sustainable and reproducible burn rate in lead tubes, in the absence of additives, was 4.8 mm s−1. In lead tubes, it was possible to reduce the burn rate further by adding fumed silica: A composition obtained by adding 10% fumed silica (add‐on basis) to a 10% Si–90% Sb6O13 composition still burned reliably at a burn rate of 2.3 mm s−1.