bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of capecitabine and oxaliplatin administered prior to and then concomitant to radiotherapy in high risk locally advanced rectal cancer
Authors: Gao Yuan‐Hong , An Xin , Sun Wei‐Jiang , Cai Juan , Cai Mu‐Yan , Kong Ling‐Heng , Lin Jun‐Zhong , Liu Guo‐Chen , Tang Jing‐Hua , Wu Xiao‐Jun , Chen Gong , Pan Zhi‐Zhong , Ding Pei‐Rong 
Published: November 2013

Background and ObjectivesSystemic failure remains a predominant issue in locally advanced rectal cancer (LARC). A new strategy using capecitabine and oxaliplatin (XELOX regimen) administered prior to and then concomitant to radiotherapy for high risk LARC is developed in our practice. The aim of the present study was to evaluate the short‐term efficacy and toxicities of this strategy.MethodsPatients were treated with one cycle XELOX regimen (oxaliplatin 130 mg/m2 on day 1 with capecitabine 1,000 mg/m2 twice daily for 14 days every 3 weeks), followed by chemoradiation (50 Gy over 5 weeks) with modified XELOX regimen (oxaliplatin dose reduction to 100 mg/m2), and total mesorectal excision. Tumor response, toxicities, and surgical complications were recorded.ResultsForty‐two patients treated with the strategy were identified. All patients completed planned dose of induction chemotherapy and concurrent chemoradiotherapy. Grade 3 toxicities were thrombocytopenia (4.8%), diarrhea (7.1%), proctitis (4.8%), and radiation dermatitis (7.1%). Five patients (12.5%) developed postoperative complications. Pathologic complete response (pCR) and nearly pCR were achieved in 7 (15.0%) and 13 patients (35.0%).ConclusionsThe preliminary results suggest that induction chemotherapy followed by chemoradiotherapy with capecitabine and oxaliplatin in LARC is well tolerated. The strategy achieves favorable short term outcome in terms of pCR and nearly pCR rate, which warrants further investigation. J. Surg. Oncol. 2014 109:478–482. © 2013 Wiley Periodicals, Inc.
Convenient Synthesis of a Polyester‐co‐Polyether Block for Assembling Biocompatible Hyperbranched Macromolecules
Authors: Elkin Igor , Hildgen Patrice 
Published: November 2013

Synthesis of a novel multifunctional block based on asymmetrically substituted pentaerythritol, succinic acid, and tetraethylene glycol is reported. The proposed reaction conditions allow selective preparation of the product in high overall yield. The block can be used in the assembly of biocompatible polyester‐co‐polyether (PEPE) hyperbranched macromolecules, which allows the product to be considered as a promising intermediate for the development of new biomedical dendrimers. As an example, the use of the “block by block” strategy is employed to obtain a second‐generation dendron. It is shown that the approach is much more efficient than the pathway of step‐by‐step grafting of separate molecular fragments.
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Micron‐Sized Polymer Particles by Membrane Emulsification
Authors: Simons J.M.M. , Keurentjes J.T.F. , Meuldijk J. 
Published: November 2013

SummaryDispersions of micron‐sized styrene droplets in water were produced by straight through microchannel arrays. The monomer droplets have been polymerized by suspension polymerization using an initiator system, which was only oil soluble. A significant amount of submicron particles was formed by secondary nucleation. The side reaction was emulsion polymerization, which was confirmed by the molecular weight distribution of the reaction product. Suppression of secondary nucleation was only partially possible by using the water soluble inhibitor NaNO2. Increasing the monomer to water ratio before polymerization resulted in less emulsion polymerization. Molecular weight was found to be strongly dependent on the initiator concentration as well as on the inhibitor concentration. It was demonstrated that polymer particles with a diameter of about 10 μm can be produced using emulsification of the monomer by microchannel arrays prior to polymerization.
Quantification of Colour Formation in PET Depending on SSP Residence Time, Temperature, and Oxygen Concentration
Authors: Rieckmann Thomas , Besse Katharina , Frei Fabian , Völker Susanne 
Published: November 2013

SummaryA systematic approach was carried out to quantify the discolouration of different poly(ethylene terephthalate) (PET) samples such as virgin bottle‐grade resins, bottle‐to‐bottle recycled chips, and bottle‐to‐bottle recycled flakes. The PET samples were treated in a fixed bed reactor in the solid‐state. The possible influencing parameters such as residence time, temperature, and oxygen partial pressure were studied by analysing the CIELAB b*‐coordinate (axis = yellow to blue) with a spectrophotometer at the end of the experiment. The PET samples were analysed once as chips respectively flakes retained from the experiments and again as plates obtained from a following standardised melting procedure. The combination of experiments and literature review results in the proposal of different discolouration mechanisms, which are influenced by temperature, residence time, and oxygen concentration. Using the design of experiments (DoE) approach, a mathematical model was compiled that can be used to predict the yellowing of the different PET grades.
A Theoretical and Experimental Kinetic Investigation of the ROP of L,L‐Lactide in the Presence of Polyalcohols
Authors: Karidi Konstantina , Pladis Prokopios , Kiparissides Costas 
Published: November 2013

SummaryThe present work deals with the experimental and theoretical investigation of the ring‐opening polymerization of L,L‐lactide with stannous octoate as a catalyst for the production of high molecular weight polymers with improved physical and mechanical properties. The polymerization of L,L‐lactide was experimentally studied at various temperatures and different monomer to initiator concentration ratio values. Subsequently, co‐initiators with different number of hydroxyl groups (i.e., 1,4‐butanediol, glycerol, di‐trimethylolpropane and polyglycidol) were utilized to obtain branched or star shaped polymers. A comprehensive mathematical model was developed based on a detailed kinetic mechanism to predict the dynamic evolution of monomer conversion and molecular weight averages (i.e., Mn, Mw of PLLA). The predictive capabilities of the mathematical model are demonstrated by a direct comparison of model predictions with literature and new experimental data on monomer conversion as well as number and weight average molecular‐weight of PLLA.
Microencapsulation of Fragrance and Natural Volatile Oils for Application in Cosmetics, and Household Cleaning Products
Authors: Tekin Rumeysa , Bac Nurcan , Erdogmus Huseyin 
Published: November 2013

SummaryIn this study, polyurethane‐urea microcapsules containing fabric softener fragrance (TeddysoftTM, by EPS) as active agents were produced by interfacial polymerization. Size, shape and morphology of the microcapsules were studied by using an optical microscope and scanning electron microscope. The effectiveness of the fragrance containing microcapsules was tested by washing hand towels in a commercial washing machine. Textile impregnation and the durability of the fragrance impregnation effect were evaluated qualitatively by perfumers, and by headspace GC analysis. Optical and scanning electron microscopic results indicated that increasing the stirring rate during the emulsion step results in microcapsules with smaller particle size, but at some point morphologies were adversely affected.
Specialised tools for a better comprehension of olefin polymerisation reactors
Authors: McKenna Timothy F.L. , Boisson Christophe , Monteil Vincent , Ranieri Elena , Tioni Estevan 
Published: November 2013

Summary2 laboratory‐scale reactor systems suitable for gas phase, and for solution or slurry polymerisations are discussed. The underlying concept behind the design and use of these reactors is that they can be used to understand the impact of conditions specific to different time scales and/or length scales inherent to large reactors that are difficult to recreate at the laboratory scale. For instance the fixed bed gas phase reactor is used to study the influence of different relative gas/solid velocities on the evolution of the molecular weight distribution of the nascent polymer. It is shown that in certain conditions, changing the heat transfer characteristics does not change the observed yield, but will impact the polymer properties. In the case of the solution reactor, the concept is to design and use a reactor to study the activation of unsupported metallocenes. Here it is shown that different metallocenes have very different activation profiles to a point where a stopped flow reactor might not be the ideal tool for their study.
Properties of Smart‐Scaled PTFE‐Tubular Reactors for Continuous Emulsion Polymerization Reactions
Authors: Lueth Fabian Gabriel , Pauer Werner , Moritz Hans‐Ulrich 
Published: November 2013

SummaryThis article presents a novel design of smart scale PTFE tubular reactor systems for continuous polymerization reactions. To optimize the flow pattern, CFD calculations and RTD experiments were done. These results led to an unique tube geometry combined with a specialized arrangement of static mixers. A comparison of heat transfer properties of two different types of tubular reactors shows the feasibility of using PTFE instead of stainless steel as reactor construction material. The versatility of the operation modes is demonstrated for emulsion copolymerization experiments with the same recipe but at the different modes.
Polyolefin Composite Synthesis: From Small Scale to kg Material
Authors: Scheel Saskia , Rosehr André , Poeppel Artur , Luinstra Gerrit A. 
Published: November 2013

SummaryPolyolefin composites were prepared by the in situ polymerization technique. Experiments were performed with mixtures of aluminum silicates and multi walled carbon nanotubes as fillers in 1 L reactors. The mixture of fillers was sonicated in toluene solution before polymerization, leading to a more stable dispersion in the solvent. Scale up to 10 L reactions gives access to kg material with well‐dispersed filler in polypropylene. The thermal properties (Tm, Tc) of the composite are basically unchanged to polypropylene without filler, like the crystallinity is.
Semi‐Batch Copolymerization of Propylene Oxide and Carbon Dioxide
Authors: Nörnberg Benjamin , Spottog Carmen , Rahlf Anne , Korashvili Revaz , Berlin Claas , Luinstra Gerrit A. 
Published: November 2013

SummaryA nanoscopic heterogeneous catalyst system based on zinc glutarate is used to prepare poly(propylene carbonate) (PPC) from CO2 and propylene oxide (PO). The catalyst was exposed to a defined humid atmosphere. The water uptake resulted in a deactivation to a minimum of 25% of the original activity, depending on time of exposure and water concentration. In addition, the progress of the copolymerization at constant pressure was monitored by measuring the CO2 uptake. It is shown that the rate is linear with time after an initial phase and that this rate is in linear correlation with the amount of catalyst. The copolymerization was also performed in several modes of discontinuous addition of PO. The productivity of the catalyst was in the range of 1.6–2.0 kg PPC/g Zn, the highest productivity reported for the zinc carboxylate catalyst system so far. High molecular weights of around 220 kg/mol (Mw) and low polydispersities of 2.2–2.5 were achieved in all experiments.
Curcumin promotes exosomes/microvesicles secretion that attenuates lysosomal cholesterol traffic impairment
Authors: Canfrán‐Duque Alberto , Pastor Óscar , Quintana‐Portillo Rocío , Lerma Milagros , de la Peña Gema , Martín‐Hidalgo Antonia , Fernández‐Hernando Carlos , Lasunción Miguel A. , Busto Rebeca 
Published: November 2013

ScopeExosomes/microvesicles are originated from multivesicular bodies that allow the secretion of endolysosome components out of the cell. In the present work, we investigated the effects of curcumin, a polyphenol, on exosomes/microvesicles secretion in different cells lines, using U18666A as a model of intracellular cholesterol trafficking impairment.Methods and resultsIn both HepG2 hepatocarcinoma cells and THP‐1 differentiated macrophages, treatment with curcumin affected the size and the localization of endosome/lysosomes accumulated by U18666A, and reduced the cholesterol cell content. To ascertain the mechanism, we analyzed the incubation medium. Curcumin stimulated the release of cholesterol and the lysosomal β‐hexosaminidase enzyme, as well as the exosome markers, flotillin‐2 and CD63. Electron microscopy studies demonstrated the presence of small vesicles similar to exosomes/microvesicles in the secretion fluid. These vesicles harbored CD63 on their surface, indicative of their endolysosomal origin. These effects of curcumin were particularly intense in cells treated with U18666A.ConclusionThese findings indicate that curcumin ameliorates the U18666A‐induced endolysosomal cholesterol accumulation by shuttling cholesterol and presumably other lipids out of the cell via exosomes/microvesicles secretion. This action may contribute to the potential of curcumin in the treatment of lysosomal storage diseases.
Fractional order hybrid system dynamics
Authors: (Stevanović) Hedrih Katica R. 
Published: November 2013

AbstractDynamics of multi deformable bodies coupled by standard light fractional order discrete continuum layers is described by coupled partial fractional order differential equations. A mathematical analogy and phenomenological mapping between generalized coordinates of fractional order discrete chain systems and eigen time functions correspond to one of infinite numbers of eigen amplitude functions of dynamics of multi deformable bodies (beams, plates or membranes) coupled by standard light fractional order discrete continuum layers are identified. Eigen fractional order vibration modes are approximately determined analytically and graphically presented. A number of theorems is defined and proofed. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling of the dynamic phenomena “stick‐slip” and “whirl” of a drill string demonstrator
Authors: Ostermeyer Georg‐Peter , Kueck Armin 
Published: November 2013

AbstractVibrations of drill strings in oil and gas well bores can reduce drilling performance or lead to damage of drill string components. These vibrations are neither optically observable nor measurable because of the geological formation. Hence usually simulations are used to understand the dynamic behavior. The test stand “OSTrator” adds more insight to this problem. The demonstrator represents a scaled drill rig granting direct access to the complex dynamic behavior of the real drill string. Two phenomena are of special interest: the stick‐slip effect, a torsional oscillation, and the whirl effect, a periodic torsional‐lateral movement with permanent wall contact. Since the OSTrator was built for showcase purposes, it has to be piloted in and out Stick‐Slip and Whirl domains by a control algorithm. Therefore efficient multi‐body‐systems able to represent these two effects in faster than real time are demanded. In this presentation, the modeling of the stick‐slip and the whirl effect are discussed. The models should be able to predict these effects and supply data to avoid or confront them. Key questions are the modeling of the wall contact and the resistance at the drill bit. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Discrete Element Approach for Wave Propagation in Thin Rods
Authors: Stühler Sven , Fleissner Florian , Seifried Robert , Eberhard Peter 
Published: November 2013

AbstractWave propagation and evoked side effects, such as material failure, are important parts of analysis of dynamically exposed structures like buildings or machinery. One of the numerical analysis tools for wave propagation is the well‐known Finite Element Method (FEM) with its impressive performance but also with the drawback of not being able to model easily material failure, discontinuities and contacts. In contrast, the Discrete Element Method (DEM) is capable to describe these effects on a meso‐scale more easily. The here selected concept is based on a DEM particle which is considered as deformable, and can establish and remove lasting bonds with other particles. The simulation example used is a thin rod that has been an extensive numerical and experimental research subject since the last century. A longitudinal wave is excited within the thin rod by simulating an impact on one end of the rod in a free‐free configuration. It is found, that the simulation data, the velocity profile and the resulting displacement at the end of the rod, are in good agreement with experimental obtained data. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Development of a miniature robot based on experience that is inspired by nature
Authors: Stevanović Ilija , Rašuo Boško 
Published: November 2013

AbstractIn this paper, using nature as inspiration, micro robot is designed. Utilizing the basic principles of the biological systems motion and modern software tools Matlab Simulink and SolidWorks a mathematical analysis and simulation of its mechanism for movement are developed. It will be shown that the Bionics along with use of modern software can be a powerful engineering tool. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the mechanics of fluid‐like growth in solid materials
Authors: Bolea Albero Antonio , Böl Markus 
Published: November 2013

AbstractLiving materials can change in mass and volume depending on the availability of nutrients and on its mechanical environment. During growth phenomena, even with mechanical properties as solids, some living materials present fluid‐like characteristics. Bodies with such behaviour can be deformed as elastic bodies under the application of loads and constrains. However, their growth can be described as the flow of the new material contribution as these loads and constrains do not let the body grow in an isotropic way. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Towards modelling the dynamics of a 3D continuum‐mechanical two‐muscle musculoskeletal system
Authors: Sprenger Michael , Schmitt Syn , Röhrle Oliver 
Published: November 2013

AbstractComputational expenses restrict the usage of continuum mechanics in modelling (parts of) the musculoskeletal system, although, continuum mechanics would provide the possibility to represent the complex mechanical behaviour of a muscle‐tendon complex (MTC). This work provides an overview on a modelling framework, which aims to achieve forward‐dynamics simulations of musculoskeletal systems by coupling three‐dimensional continuum‐mechanical‐based finite element simulations to rigid‐body simulations based on a simplified two‐muscle upper arm model. Here, the focus is on implementing a sophisticated representation of the skeletal MTC and tissue‐bone interaction. The three‐dimensional continuum‐mechanical description of the skeletal muscle is described within the framework of finite elasticity. To model the MTC, two additional parameters are introduced providing the possibility to describe muscle tissue, tendon tissue, and soft tissue within one set of constitutive equations. Further, a realistic fibre orientation for the skeletal muscles and contact mechanics between the muscles and the bones is considered. For different elbow flexion angle positions, the muscles' mechanical state is compared with and without considering contact mechanics. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Porous‐media simulation of bone‐cement spreading during vertebroplasty
Authors: Wagner Arndt , Bleiler Christian , Stadelmann Vincent , Windolf Markus , Gueorguiev‐Rüegg Boyko , Köstler Harald , Boger Andreas , Röhrle Oliver , Ehlers Wolfgang 
Published: November 2013

AbstractThe reinforcement of porous vertebral cancellous bone by the injection of bone cement is a practical procedure for the stabilisation of osteoporotic compression fractures and other weakening lesions. This contribution concerns the reproduction and prediction of the resulting bone‐cement distribution during the injection procedure by means of numerical simulation. A detailed micromechanical (locally single‐phasic) model exhibits the drawback that all geometrical and physical transition conditions of the individual parts of the complex aggregate have to be known. Therefore, we rather proceed from a macroscopic (and multi‐constituent) continuum‐mechanical model based on the Theory of Porous Media. In this regard, the homogenisation of the underlying micro‐structure results in a model of three constituents: these are the solid bone skeleton, which is saturated by the liquid bone marrow that may be displaced by the injected liquid bone cement. The influence of the micro‐architecture of the pore space on the spreading of the bone cement is considered by a spatial diversification of the anisotropic permeability tensors, obtained through image processing techniques applied to medical imaging data (µCT). The numerical investigation of the strongly coupled problem enables the study of vertebroplasty and allows for the comparison between the simulation results and the experimentally determined bone‐cement distribution that were imaged during injections. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A parametric study on creep‐fatigue endurance of welded joints
Authors: Gorash Yevgen , Chen Haofeng 
Published: November 2013

AbstractThis work is devoted to parametric study on creep‐fatigue endurance of the steel AISI type 316N(L) weldments defined as type 3 according to R5 Vol. 2/3 procedure at 550°C. The study is implemented using a novel direct method known as the Linear Matching Method (LMM) and based upon the creep‐fatigue evaluation procedure considering time fraction rule for creep‐damage assessment. Seven geometrical configurations of the weldment, which are characterised by individual values of a geometrical parameter ρ, are proposed. Parameter ρ, which represents different grades of TIG dressing, is a ratio between the radius of the fillet of the remelted metal on a weld toe and the thickness of welded plates. For each configuration, the total number of cycles to failure N* in creep‐fatigue conditions is assessed numerically for different loading cases including normalised bending moment $\tilde{M}$ and dwell period Δt. The obtained set of N* is extrapolated by the analytic function dependent on $\tilde{M}$, Δt and ρ. Proposed function for N* shows good agreement with numerical results obtained by the LMM. It is used for the identification of Fatigue Strength Reduction Factors (FSRFs) effected by creep and dependent on Δt and ρ. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
3D finite elements to model electromechanical coupled solids at failure
Authors: Linder Christian 
Published: November 2013

AbstractThis work presents an extension of newly developed 3D finite elements to model failure in purely mechanical based materials [1, 2] to electromechanical coupled materials. Following the approach suggested in [6] for the plane setting, new finite elements are developed, which in addition to resolving strong discontinuities in the mechanical displacement field are capable of modeling strong discontinuities in 3D also in the electric potential. An application to a 3D off‐centered three point bending test under combined mechanical and electrical loading outlines the performance of the newly developed finite elements. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)