bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel method for internal nasal valve reconstruction: H‐graft technique
Authors: Tastan Eren , Demirci Munir , Aydin Emine , Aydogan Filiz , Kazikdas K. Cagdas , Kurkcuoglu Melih , Ugur M. Birol 
Published: January 2011

AbstractObjectives:The aim of this study was to determine the efficacy of a novel method for internal nasal valve reconstruction that enables lateralization of the superior segment of upper lateral cartilages (ULC) from the septum to a greater extent than the spreader graft method with lateral wall support.Study Design:Prospective, controlled study set at a tertiary medical center.Methods:The study group was composed of 19 consecutive patients with pure internal nasal valve dysfunction who underwent surgery with the presented technique. All patients completed the Nasal Obstruction Symptom Evaluation (NOSE) and Rhinoplasty Outcomes Evaluation (ROE) tests preoperatively and at 12th month postoperative control to compare functional and aesthetic outcomes.Results:Based upon pre‐ and postoperative calculations made using NOSE scores, there was significant improvement regarding nasal blockage or congestion, troubled breathing and sleeping, and air through nose during exercise, respectively (P< .05). There were no aesthetic changes encountered by the patient when pre‐ and postoperative ROE scores were compared (P> .05).Conclusions:The H shape of the graft not only improves the graft stability on dorsal septum but also has the advantage of combining the spreader and the splay effects. Current data from this prospective study suggest that this technique may be used in the surgical treatment of internal nasal valve dysfunction. Laryngoscope, 2011
Preparation of 3D Fibroin/Chitosan Blend Porous Scaffold for Tissue Engineering Via a Simplified Method
Authors: Ruan Yuhui , Lin Hong , Yao Jinrong , Chen Zhengrong , Shao Zhengzhong 
Published: January 2011

AbstractIn this work, we developed a simple and flexible method to manufacture a 3D porous scaffold based on the blend of regenerated silk fibroin (RSF) and chitosan (CS). No crosslinker or other toxic reagents were used in this method. The pores of resulted 3D scaffolds were connected with each other, and their sizes could be easily controlled by the concentration of the mixed solution. Compared with pure RSF scaffolds, the water absorptivities of these RSF/CS blend scaffolds with significantly enhanced mechanical properties were greatly increased. The results of MTT and RT‐PCR tests indicated that the chondrocytes grew very well in these blend RSF/CS porous scaffolds. This suggested that the RSF/CS blend scaffold prepared by this new method could be a promising candidate for applications in tissue engineering. magnified image
Planar Block Copolymer Membranes by Vesicle Spreading
Authors: Dorn Jan , Belegrinou Serena , Kreiter Max , Sinner Eva‐Kathrin , Meier Wolfgang 
Published: January 2011

AbstractAn easy route to planar solid‐supported polymer membranes by vesicle spreading is described. Pre‐organized poly(butadiene)‐block‐poly(ethylene oxide)(PB‐PEO) assemblies were spread on two different supports, i.e. strongly hydrophilic glass surfaces and ultrasmooth gold substrates. Polymer membranes were produced on a hydrophilic support by spreading hydroxyl‐functionalized polymer vesicles, while covalently immobilized polymer membranes were obtained by spreading LA‐functionalized polymer vesicles on gold substrates. Covalently bound membranes were further incubated with the peptide polymyxin B. Interactions with the polymer membrane were detected by EIS. These systems are of great interest to fundamental membrane science and have potential in technological applications, such as drug screening and (bio)sensing. magnified image
Tailored Media for Homogeneous Cellulose Chemistry: Ionic Liquid/Co‐Solvent Mixtures
Authors: Gericke Martin , Liebert Tim , Seoud Omar A. El , Heinze Thomas 
Published: January 2011

AbstractCo‐solvents can minimize two of the major problems associated with the use of ionic liquids (ILs) as solvents for homogeneous derivatization of cellulose: high viscosity and limited miscibility with non‐polar reagents or reaction products. Thus, the effects of 18 solvents and 3 binary solvent mixtures on cellulose solutions in three ILs were systematically studied with respect to the solution phase behavior. The applicable limits of these mixtures were evaluated and general guidelines for the use of co‐solvents in cellulose chemistry could be advanced: Appropriate co‐solvents should have $E_{{\rm T}}^{{\rm N}} $ values (normalized empirical polarity) > 0.3, very low “acidity” (α < 0.5), and relatively high “basicity” (β ≥ 0.4). Moreover, novel promising co‐solvents and binary co‐solvent mixtures were identified. magnified image
A New Modifier for Silica in Reinforcing SBR Elastomers for the Tyre Industry
Authors: Bertora Alessandro , Castellano Maila , Marsano Enrico , Alessi Matteo , Conzatti Lucia , Stagnaro Paola , Colucci Giovanna , Priola Aldo , Turturro Antonio 
Published: January 2011

AbstractA new alkoxysilane was used to reduce the hydrophilic character of the silica used in reinforcing styrene/butadiene elastomers for the tyre industry. The surface properties of silica modified with 17 wt.‐% of this silane were estimated by inverse GC. A clear change from hydrophilic to hydrophobic character was observed. Styrene/butadiene copolymers loaded with modified silicas were characterized were characterized using vulcanization tests, stress/strain measurements and morphological analysis. The best tensile properties were obtained with TESPT‐modified silica. The properties of the compound loaded with sb1‐pre‐grafted silica are scantily lower that the ones of the other compounds. This difference must be ascribed to a higher crosslink density given by the sulfur deriving from the TESPT decomposition during the vulcanization process. magnified image
Nanoreactor‐Assisted Polymerization Toward Stable Dispersions of Conductive Composite Particles
Authors: Korovin Alexey N. , Sergeyev Vladimir G. , Pyshkina Olga A. , Hanske Christoph , Fery Andreas , Wittemann Alexander , Tsarkova Larisa 
Published: January 2011

AbstractWe demonstrate the functioning of a macromolecular nanoreactor which guides a reaction in a confined volume and leads toward improved functional properties of a product material. In our approach, the polymerization of aniline (ANi) is conducted within the interfacial volume of spherical polyelectrolyte brushes (SPB) which are densely affixed to colloidal particles. The SPB provide optimal conditions for matrix polymerization by the efficient confinement of ANi monomers within the finite volume of polyelectrolyte brushes and controlled delivery of the oxidizing reagent to the reaction volume. The excellent kinetic stability of the resulting core–shell particles together with the high macroscopic conductivity of the respective composite open up perspectives for novel materials (a conductive ink). magnified image
Highly Efficient Synthesis of Low Polydispersity Core Cross‐Linked Star Polymers by Ru‐Catalyzed Living Radical Polymerization
Authors: Goh Tor Kit , Yamashita Satoshi , Satoh Kotaro , Blencowe Anton , Kamigaito Masami , Qiao Greg G. 
Published: January 2011

AbstractThe efficient formation of low polydispersity core cross‐linked star (CCS) polymers via controlled/living radical polymerization (LRP) and the arm‐first approach was found to be dependant on the mediating catalyst system. The Ru catalyst, Ru(Ind)Cl(PPh3)2 Cat. 1, and tertiary amine co‐catalyst were used to synthesize highly living poly(methyl methacrylate) (PMMA) macroinitiators, which were then linked together with ethylene glycol dimethacrylate (EGDMA) to form PMMAarmPEGDMAcore CCS polymers. The quantitative and near‐quantitative synthesis of CCS polymers were observed for low to moderate molecular weight macroinitiators ($\overline {M} _{{\rm n}} $ = 8 and 20 kDa), respectively. Lower conversions were observed for high‐molecular weight macroinitiators ($\overline {M} _{{\rm n}} $ ≥ 60 kDa). Overall, an improvement of between 10 and 20% was observed when comparing the Cat. 1 system to a conventional Cu‐catalyzed system. This significant improvement in macroinitiator‐to‐star conversion is explained in the context of catalyst system selection and CCS polymer formation. magnified image
Studies on Morphology and Conductivity of Poly (N‐methyl aniline) Nanoparticles Prepared in Nonstirred Reaction Medium
Authors: Chabukswar Vasant , Dhomase Navnath , Bhavsar Sanjay , Horne Amit , Mohite Kakasaheb , Gaikwad Vishwas 
Published: January 2011

AbstractSummary: Polyaniline has elicited the most interest due to its wide range of applications in many fields. However insolubility and infusibility are the main factors that affect the application of polyaniline. We have studied and worked on the synthesis of dispersible polyaniline and the results are described here. Poly (N‐methyl aniline) PNMANI nanoparticles with controllable morphology and sizes were prepared by removing a routine operation stirring from the conventional method of synthesis and using acrylic acid as a soft template. It is found that polymer formed in the non‐stirring experiment predominantly produces highly dispersible, smooth nanoparticles with controllable morphology and sizes. These nanoparticles have large surface area and thereby high conductivity. Mechanism for generation of well dispersed and smooth nanoparticles is supported by homogeneous nucleation of polymer nanoparticles in non stirred experiments and the use of acrylic acid as a soft template. In the case of the experiment where the reaction mixture was stirred at 1000 RPM comparatively coral‐like, granular and uncontrolled polymer particles were formed. These coral like granular particles were having comparatively small surface area and less conductivity. Conductivity measurements, UV‐ visible, XRD, FTIR spectroscopy and SEM were performed to characterize the product. This method can be used to synthesize highly conductive polymers in minimum time and bulk quantity.
Physicochemical Characterization of Two Polysulfon‐Amides in Dilute Solution
Authors: Chen Ye , Wu Di , Li Jun , Chen Shenghui , Wang Xiaofeng , Zhang Yumei , Wang Huaping 
Published: January 2011

AbstractSummary: As one class of high temperature resistant aromatic polymers, polysulfonamides (PSA) are widely used in industry, physicochemical properties and conformation in solution have not been disclosed yet. In this work, the dilute solution behaviour of poly(m‐diphenylsulphone terephthal amide) (m‐PSA) was investigated by laser light scattering (LLS) and viscometry. The results showed that the m‐PSA exists as single chains both in dimethylsulfoxide (DMSO) and dimethylformamide (DMF). The value of radius of gyration to hydrodynamic radius (s/Rh) indicats that the m‐PSA has a random coil conformation in solution. Both the persistence length a and the characteristic ratio C∞ indicate that the m‐PSA chain is flexible in solution. The Mark‐Houwink equation of m‐PSA in DMSO was determined as [η] = 1.62 × 10−5M, and the exponent of 0.87 supports the assumption that m‐PSA forms random coils in DMSO‐solution at 25 °C. It was found that the flexibility of the PSA was affected when 4,4'‐diphenylsulphone terephthalamide monomer was incorporated in backbone. The PSA random copolymer (r‐PSA) with a comonomer ratio of 3:1 (4,4′‐diaminodiphenyl‐ sulfone to 3,3′‐diaminodiphenylsulfone) also had a random coil conformation in DMF; the rigidity increased, while the mobility of the chain was maintained.
Comparison of the Effect of an Organoclay, Triphenylphosphate, and a Mixture of Both on the Degradation and Combustion Behaviour of PC/ABS Blends
Authors: Feyz Elham , Jahani Yousef , Esfandeh Masoud 
Published: January 2011

AbstractSummary: Polycarbonate Acrylonitrile‐Butadiene‐Styrene blends (PC/ABS) with flame retardants Triphenyl Phosphate (TPP), nanoclay and their mixtures were prepared in a twin‐ screw extruder. The morphological properties were characterized by X‐ray diffractometry (XRD) which showed the intercalated structure of nanoclay in the matrix. Thermal stability of the samples was studied using Thermogravimetric Analysis (TGA), and the degradation kinetic parameters were determined using various methods including Kissinger, Flynn‐Wall‐Ozawa and Coats‐Redfern methods. It was found that the sample containing both TPP and nanoclay has the highest activation energy. The activation energy order of PC/ABS blends with different flame retardant packages, obtained by Kissinger method agrees well with that obtained by Coats‐Redfern. Cone calorimetry and limited oxygen index (LOI)/underwriters laboratory 94 (UL94) methods were used to investigate the fire behaviour and flammability of materials. The reduced mass loss rate (MLR), peak heat release rate (PHRR) and enhanced LOI of the composite containing mixture system confirmed a synergistic effect of TPP and nanoclay.
Properties and Characterization of Organoclay/Dimethacrylate Composites Obtained by In Situ Photopolymerization
Authors: Rigoli Isabel C. , Batista Tatiana , Cavalheiro Carla C. S. , Neumann Miguel G. 
Published: January 2011

AbstractSummary: Composites of dimethacrylates/organoclay were obtained by in situ photopolymerization of Bis‐GMA (Bisphenol A glycidyl methacrylate) and TEGDMA (tetraethyleneglycol dimethacrylate) in the presence of camphorquinone and DEEMA (2‐(diethylamino)ethyl methacrylate). The composites contained up to 10% wt/wt of organoclays. Monomer conversion and polymerization kinetics were determined by real time Fourier‐Transform Infrared Spectroscopy – Attenuated Total Reflectance (FTIR‐ATR), and showed an increase of conversion with addition of the clay. The storage modulus E' of the composites also had a marked dependence on the composite composition and increased with addition of clay at all temperatures. Tg also increases with clay content. X‐Ray Diffraction (XRD) analysis shows that the clay is completely exfoliated for the composites with a lower proportion of clay, whereas for larger clay/polymer proportions peaks corresponding to the interlamellar distance of the clay are still observed. This is probably due to the fact that the amount of monomers in the initial formulation was not sufficient to delaminate the clay. Scanning Electron Microscopy (SEM) images indicate a quite homogenous copolymer, with some clay aggregates that increase in size and number for the higher filler loadings in agreement with the XRD results.
Synthetic Strategies to Combine High Performance Benzoxazine Thermosets with Polymers
Authors: Kiskan Baris , Yagci Yusuf 
Published: January 2011

AbstractSummary: Polybenzoxazines are newly developed thermosetting polymers exhibiting versatility in a wide range of applications including electronics and aerospace industries. They exhibit highly competitive combination of properties compare to the conventional thermosets. In this paper we present synthetic strategies to incorporate thermally curable benzoxazine functions into polymers as main and side chain groups in order to further improve various properties. The strategies successfully employed include monomer synthesis, macromonomer method, polycondensation, oxidative polymerization, photo‐polymerization, click chemistry and hydrosilylation processes. In the case of macromononomer method functional initiators were used in various controlled/living polymerizations to give polymers with benzoxazine end groups. The thermal curing behaviors of the obtained polymers were also demonstrated.
Polysulfones on the Base of New Diallylaminophosphonium Salts
Authors: Gorbunova M. N. , Vorob'eva A. I. 
Published: January 2011

AbstractSummary: Methods for the synthesis of new diallylaminophosphonium salts have been developed. The reactivity of tris(diethylamino)diallylaminophosphonium tetrafluoroborate (DAAP‐BF4) and chloride (DAAP‐Cl) through free‐radical copolymerization with sulfur dioxide have been studied. Diallylaminophosphonium salts do not undergo free radical homopolymerization but copolymerize at a low rate with vinyl monomers. DAAP‐BF4 and DAAP‐Cl show high activity in copolymerization with sulfur dioxide. The structure of the polysulfones obtained has been identified by NMR 13C. The investigations carried out have shown that DAAP‐BF4 and DAAP‐Cl copolymerize with sulfur dioxide, both double bonds participating with formation of cis‐, trans‐stereoisomeric pyrrolidine structures in a cyclolinear polymer chain. The new polysulfones possess a broad spectrum of bactericidal effect.
Synthesis of New Amphiphilic Comb‐Like Copolymers Based on Maleic Anhydride and α‐Olefins
Authors: Kudina Olena , Budishevska Olga , Voronov Andriy , Kohut Ananiy , Khomenko Olena , Voronov Stanislav 
Published: January 2011

AbstractSummary: Novel amphiphilic comb‐like poly(α‐olefin‐co‐maleic anhydride) with a controlled ratio of hydrophilic (polyoxyethylene) and hydrophobic (polymethylene) side chains have been synthesized and characterized. The comb‐like copolymers are soluble in organic and aqueous media and form micelles whose behaviour could be correlated to the chemical structure of polymers. We foresee that amphiphilic properties of the novel comb‐like polymers are obviously the basis of new architectures in solution which could be used in a broad range of applications. Using micelles from these copolymers, silver nanoparticles with a narrow particle size distribution have been obtained as stable dispersion in both polar and non‐polar media.
Mechanical properties of blood clots – a new test method
Authors: Krasokha N. , Theisen W. , Reese S. , Mordasini P. , Brekenfeld C. , Gralla J. , Slotboom J. , Schrott G. , Monstadt H. 
Published: January 2011

AbstractA blood clot needs to have the right degree of mechanical, chemical and biological properties to stem the flow of blood and yet to be suitable for lytic enzymes or mechanical thrombectomy so as not to form a thrombotic event. The origin and understanding of these mechanical properties are still not known in detail. Clots are made of a three‐dimensional network of fibrin fibers stabilized through ligation with a transglutaminase, factor XIIIa. New methods to achieve information about mechanical properties were established in this work. We performed compressive strength experiments of aged human blood clots. Furthermore after the set up of a new test environment, it was possible to perform tensile strength measurements of aged animal blood clots. Stress strain curves of aged clots were measured and discussed. The viscoelastic properties of the clot material were quantitatively described. This work should make a contribution to a better understanding of the behaviour of aged blood thrombus bulk material and induced mechanical stress.In der Behandlung ischämischer Schlaganfälle sind mechanische, chemische und biologische Eigenschaften von Blutgerinnseln von essentieller Bedeutung und entscheidend über den Erfolg einer Lyse‐Therapie bzw. mechanischer Thrombektomie. Die Einflussfaktoren der Gerinnungsbedingungen auf die mechanischen Eigenschaften sind jedoch bisher noch nicht eingehend untersucht. Aus Schrifttum ist bekannt, dass auf mikrostruktureller Ebene die Blutgerinnsel aus Fibrinfasern, die untereinander in Knotenpunkten verbunden sind und in der Gesamtheit ein dreidimensionales Netzwerk bilden, bestehen. Dabei haben besonders die Faserdicke und die Knotenpunktendichte einen direkten Einfluss auf die mechanischen Eigenschaften eines Thrombus. Im Rahmen dieser Arbeit wurden Druck‐ und Zugversuche an Thrombus‐Proben (hergestellt aus humanem bzw. tierischem Blut) durchgeführt und die Messergebnisse hinsichtlich der Gerinnungsbedingungen diskutiert.
Stabilizing ultra‐hydrophilic surfaces by an exsiccation layer of salts and implications of the Hofmeistereffect
Authors: Jennissen H.P. 
Published: January 2011

AbstractUltra‐hydrophilic titanium surfaces can be prepared in a variety of ways by acid etching. However such surfaces are unstable in air and in water so that a storage for several years, as is necessary for clinical use, is a major problem. Ultrahydrophilic surfaces on miniplates prepared by chromosulfuric acid (CSA) enhancement showing dynamic advancing and receding contact angles of 0° (no hysteresis) can be easily stabilized and stored at room temperature in the dry state in air atmosphere. After evaporation of the aqueous phase of a salt containing solution (e. g. PBS) an exsiccation layer composed of specific ions is formed on the dry metal oxide surface exerting the stabilizing effect. The mechanism involved in this stabilizing effect of salts appears to be governed by the Hofmeister Effect. Ultra‐hydrophilic CSA (chromsulfuric acid) etched surfaces can be stabilized by an exsiccation layer for over 3 years without loss of hydrophilicity.Ultra‐hydrophile Titanoberflächen können auf verschiedenen Wegen gewonnen werden. Diese Oberflächen verlieren jedoch sowohl in der Luft als auch in Wasser ihre ultra‐hydrophilen Eigenschaften, wodurch die Lagerung über mehrere Jahre, wie sie für Implantate notwendig ist, zum Problem wird. Ultrahydrophile Oberflächen auf Titanplättchen, die mit Chromschwefelsäure (CSA) veredelt wurden und dynamische Vorrück‐ und Rückzugswinkel von 0 Grad (keine Hysterese) aufweisen, können leicht im trockenen Zustand bei Zimmertemperatur in Luftatmosphäre stabilisiert und gelagert werden. Nach Evaporierung der wässrigen Phase einer Salzlösung (z. B. PBS) bildet sich auf der Metalloberfläche eine Exsikkationsschicht bestehend aus einer spezifischen Ionenzusammensetzung, die den stabilisierenden Effekt hervorruft. Der zugrunde liegende Mechanismus für die Stabilisierung von Exsikkationsschichten scheint im Hofmeister‐Effekt zu liegen. Ultra‐hydrophile CSA (Chromschwefelsäure) geätzte Oberflächen können durch eine Exsikkationsschicht für 3 Jahre stabilisiert und gelagert werden ohne Hydrophilizitätsverlust.
A model of market‐making with imperfect information
Authors: Hirst I. R. C. 
Published: January 2011

AbstractAlthough the prevention of false markets is one of the major concerns of stock market authorities in the UK and elsewhere, until recently, the theoretical literature on the workings of markets with imperfect information has been sparse. This paper analyses the problem of providing liquidity to investors when price‐sensitive information is unequally distributed.Specifically we shall model the activities of a market‐maker when certain traders have price‐sensitive information unavailable to other market participants. Our model will show how the bid‐asked spread would be determined in such a market. It is useful in explaining certain tactics employed by stock market traders and in suggesting alternative ways of evaluating market efficiency.The theory is developed in three sections: (1) the determination of the bid‐asked spread for a single, isolated transaction; (2) the determination of the bid‐asked spread in a continuous market; (3) the relationship between the spread and the size of transaction.
Resource allocation in the nationalized energy sector of the United Kingdom
Authors: Harris D. J. , Davies B. C. L. 
Published: January 2011

AbstractResource allocation in the energy sector of the United Kingdom is a difficult area to plan, because demand and supply projections need to embrace both the large private sector oil industry and the public sector fuel industries. In addition, relationships between the latter are complex as they involve both competition and co‐ordination. One approach to the problem has been to find common ground in the concept of marginal cost pricing, but there are practical difficulties in application. Government has encouraged the use of analytical techniques, such as corporate planning, by the fuel industries as a means of co‐ordination in areas where market mechanisms may no longer always be effective.