bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal Degradation and Kinetics of Poly(3‐hydroxybutyrate)/Organoclay Nanocomposites
Authors: Erceg Matko , Kovačić Tonka , Klarić Ivka 
Published: July 2008

AbstractPoly(3‐hydroxybutyrate)/Cloisite30B (PHB/30B) nanocomposites were prepared by solution‐intercalation method. The influence of 30B content on the thermal stability of PHB was investigated. With the addition of 3 wt. % of 30B the highest thermal stability of PHB was achieved. The kinetic analysis of the non‐isothermal degradation was performed using the isoconversional Friedman method and invariant kinetic parameters method.
Relaxation Processes and Glass Transition in Polymer Filled with Nanoparticles
Authors: Lopez Ivan Joel , Dolidze Vladimir , Rivera Manuel , Aliev Fouad 
Published: July 2008

AbstractWe report the results of the investigations of the influence of filling of polymer with Aerosil nanosize particles on the glass transition and dynamics of the α‐ and the β‐relaxation processes in poly(n‐octyl methacrylate) by dielectric spectroscopy and differential scanning calorimetry (DSC). The polymer was filled with hydrophilic and hydrophobic Aerosil particles of 12 nm diameter. In filled polymers the characteristic frequency of the alpha‐process was shifted to higher frequencies in comparison with pure bulk polymer at the same temperature. This suggests that the filling of the polymer with nanoparticles has resulted in the shift of its glass transition temperature Tg. This change in Tg was mainly due to the existence of a developed solid particle‐polymer interface and the difference in the dynamic behavior of the polymer in the surface layers at this interface compared to the bulk behavior. This result was in agreement with DSC experiments.
Polymer Based Nanocomposites with PhenethylPOSS as Nanofiller Investigated by Dielectric Spectroscopy and Gas Transport Measurements
Authors: Hao N. , Böhning M. , Wohlrab S. , Schönhals A. 
Published: July 2008

AbstractPolyhedral oligomeric silsesquioxane with phenethyl substituents (PhenethylPOSS) as nanofiller was incorporated within Poly(bisphenol A carbonate) (PBAC) as matrix. Dielectric spectroscopy proved an almost complete miscibility of PhenethylPOSS up to 7 wt. %. At higher concentrations phase separation yields composites with a PBAC‐rich matrix and POSS‐rich domains which posses well shaped interfaces. The nanocomposites were also investigated with respect to their gas transport behaviour. An increase of the gas permeability was found at higher PhenethylPOSS concentrations, which is due to the phase separated structure.
Morphology of Different Epoxy‐Amine Systems Modified with a Thermoplastic: Influence of Temperature, Thermoplastic Concentration and Molecular Structure of Epoxy Systems
Authors: Ramírez Carmen , Rico Maite , López Joaquín , Montero Belén , Ladra Marcelino 
Published: July 2008

AbstractThe morphologies generated by polymerization induced phase separaron (PIPS) in different epoxy‐amine systems modified with a thermoplastic, polystyrene (PS), were studied by SEM. The amino groups of the epoxy‐amine systems were provided by a monoamine and a diamine in different proportions, so that the resulting polymer would vary from a linear polymer (epoxy‐MA) to a highly crosslinked polymer (epoxy‐DA). The effects of reaction temperature, initial modifier concentration and degree of crosslinking of epoxy‐amine system on the morphology were discussed and trends for the size, distribution and concentration of dispersed particles were deduced. Different types of morphologies were obtained depending on the initial PS content. Typical morphologies of compositions close to critical point were observed for the 9 and 12 wt. % of PS in all the studied systems.
Preparation of Metal Microdots and Microdiscs by Using Honeycomb Template Prepared by Self‐organization
Authors: Hirai Yuji , Yabu Hiroshi , Shimomura Masatsugu 
Published: July 2008

AbstractHoneycomb‐patterned films were prepared by using orderly arranged water droplets as templates. By using the honeycomb‐patterned films as templates, Pt/Pd metal microdot arrays were formed on solid substrates. Silver layer was formed on the Pt/Pd layer by electroless deposition, and then, the microdiscs of Ag were obtained by removing the substrate.
Monte Carlo Simulations of Self‐Assembling Copolymer Brushes
Authors: Romiszowski Piotr , Sikorski Andrzej 
Published: July 2008

AbstractWe studied a simplified model of a polymer brush formed by linear chains, which were restricted to vertices of a simple cubic lattice. The macromolecules consisted of a sequence of two different kinds of united atoms arranged in a specific sequence. The chains were grafted to an impenetrable surface, i.e. they were terminally attached to the surface with one end. The model system was studied at different solvent quality from good to poor solvent. The properties of this model system were determined by means of Monte Carlo simulation using a Metropolis‐like sampling algorithm based on local changes of chain's conformations. The size and the structure of the brush were determined.
Direct Observation of Dye‐Containing Amphiphilic Copolymer in the Honeycomb‐Patterned Film
Authors: Kojima Miki , Yabu Hiroshi , Shimomura Masatsugu 
Published: July 2008

AbstractHoneycomb‐patterned film was prepared by casting chloroform solution of hydrophobic polymer and dye‐containing amphiphilic copolymer under humid conditions. The confocal laser scanning microscopy image shows that amphiphilic copolymer is localized around the pores of the honeycomb‐patterned film.
Sorption Characteristics of Porous Styrene‐Divinylbenzene Copolymers Filled with Modified Silica
Authors: Bolbukh Yulia , Kuzema Pavlo , Tertykh Valentin , Gawdzik Barbara 
Published: July 2008

AbstractThe structural parameters of porous styrene‐divinylbenzene copolymer, unfilled and filled with silica containing surface trimethylsilyl and silicon hydride groups were studied by aniline and p‐chloroaniline adsorption. It has been shown that embedding of chemically modified silica affects the material porosity and decreases the copolymer swelling in benzene.
Development of Polymer Nanocomposites as Electrolyte Membranes
Authors: Morozan Adina , Dumitru Anca , Nastase Claudia , Nastase Florin , Stamatin Ioan 
Published: July 2008

AbstractConfidence in the potential of hydrogen as an energy vector and fuel bring the opportunities for enhancing electrolyzer performance. The aim of this paper is to develop new polymer nanocomposites as electrolyte membranes for PEM‐electrolyzer. A series of nanocomposite membranes, including GEFC/TiO2, GEFC/CNTs, and GEFC/TiO2CNTs have been developed and characterized by FT‐IR spectroscopy and AFM. The application of polymer nanocomposite membranes in electrochemical cells for water electrolysis was investigated. Experimental results obtained with respect to performance are reported and discussed related to GEFC membrane.
Technique for determining when plantar heel pain can be neural in origin
Authors: Dellon A. Lee 
Published: July 2008

AbstractThe surgeon doing microsurgery will encounter problems related to the heel not only in terms of how to reinnervate the transferred tissue, but also in patients presenting with heel pain. While most heel pain is thought to be related to the plantar fascia arising from the calcaneus, conceptually heel pain can be of neural origin. The technique for documenting sensibility in the heel is described using the Pressure‐Specified Sensory Device™. Knowledge of calcaneal nerve sensibility can determine whether there is sufficient sensation to prevent ulceration, whether there is a nerve entrapment that would benefit from neurolysis, or whether there is a neuroma that would benefit from resection. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Stereotactic image‐guided navigation in the preoperative imaging of perforators for DIEP flap breast reconstruction
Authors: Rozen W. M. , Ashton M. W. , Stella D. L. , Phillips T. J. , Taylor G. I. 
Published: July 2008

AbstractPreoperative imaging is sought prior to DIEA (Deep Inferior Epigastric Artery) perforator flaps due to the potential for maximizing operative success and minimizing operative complications. Recent advances include the use of computed tomography (CT) angiography (CTA) and magnetic resonance angiography. Image‐guided stereotactic surgery is a recent technique that has been used with success in several fields of surgery. The variability of perforator anatomy makes DIEA perforator flap surgery a suitable candidate for such technology, but as yet this has not been described. A study was undertaken to determine the feasibility of CT‐guided stereotaxy technique in DIEA perforator flap surgery and to compare findings with both conventional CTA and operative findings. Five consecutive patients planned for an elective DIEA perforator flap were recruited. Each patient underwent preoperative imaging of the anterior abdominal wall vasculature with both conventional CTA and CT‐guided stereotactic imaging. Imaging findings were compared to operative findings. In all cases, all the major perforators were accurately localized with stereotactic imaging and with conventional CTA. Stereotactic navigation demonstrated a slightly better (nonsignificant) correlation with perforator location than conventional CTA. As such, CT‐guided stereotactic imaging is an accurate method for the preoperative planning of DIEA perforator flaps, providing additional and potentially more accurate data to conventional CTA. With no additional scanning required, the method described in this paper allows the combined use of both methods for preoperative planning. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
In vitro and in vivo evaluation of a biodegradable chitosan–PLA composite peripheral nerve guide conduit material
Authors: Xie Feng , Li Qing Feng , Gu Bin , Liu Kai , Shen Guo Xiong 
Published: July 2008

AbstractChitosan, a nature biodegradable material, has good biocompatibility but poor physical properties to serve as a nerve conduit. In this study, polylactic acid (PLA) was added to chitosan to form a composite material with improved intensity and elasticity, to be used as nerve conduits. The chitosan–PLA nerve conduits were fabricated with a mold casting/infrared dehydration technique. The constituent ratio of PLA and chitosan of 1:5 (v:v) was chosen to give the composite material both good mechanical properties and good biocompatibility. An in vitro cytotoxicity test showed that the chitosan–PLA material was not cytotoxic. The conduits were proved biodegradable and had many micropores to allow permeability. We evaluated chitosan–PLA nerve conduits as a guidance channel to repair 10 mm gaps in rat sciatic nerves. Nerve autograft and silicon conduits were used as the control. After 12 weeks, the regenerating nerves in three groups succeeded in passing through the nerve gap and reinnervating the muscle. Assessments, including ECG, histomorphometric evaluation, and weighing of triceps calf muscle, showed that the functional recovery of sciatic nerve was better in chitosan–PLA conduit group than in the silicon conduit group (P < 0.05), but the differences between the chitosan–PLA conduit group and the nerve autograft group were not significant (P > 0.05). Therefore, the chitosan–PLA guide proved to be a promising nerve conduit. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Secondary nerve reconstruction using vein conduit grafts for neglected digital nerve injuries
Authors: Lee Yen‐Hsun , Shieh Shyh‐Jou 
Published: July 2008

AbstractDigital nerve defects can result from neglected nerve injuries. The standard method of reconstruction is nerve grafting, but donor‐site morbidity encourages searching for alternative graft materials, including vein conduit grafts. From 1995–2005, three patients with neglected digital nerve injuries received vein conduit grafting for digital nerve reconstruction in our hospital. The interval between the injury and the reconstructive procedure ranged from 17 days to 2 years, and the length of the defects ranged from 0.8 to 2.5 cm. All the vein grafts were harvested from the distal forearm. Patient 1 had a moving and a static two‐point discrimination (M2PD and S2PD) of 3 and 4 mm, respectively, at a 12‐year follow‐up. Patient 2 had an M2PD of 5 mm and S2PD of 6 mm at an 11‐year follow‐up, and the patient 3 had both an M2PD and S2PD of 4 mm at a near 3‐year follow‐up. They all achieved useful sensory function (S3 and S3+) by modified Highet and Sander criteria. Although previous studies showed secondary repair using vein grafts yielded worse sensory recovery than that of primary repair, in our cases, secondary digital nerve reconstruction with vein conduit grafts gives excellent results at the long‐term sensory evaluation, two of them with more than 10 years' follow‐up. To the best of our knowledge, this might be the longest follow‐up after secondary digital nerve reconstruction using a vein conduit graft. It bears the advantages of readily accessible, no donor‐site morbidity, and compatible in size with digital nerves. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Isometric tetanic force measurement method of the tibialis anterior in the rat
Authors: Shin Richard H. , Vathana Torpon , Giessler Goetz A. , Friedrich Patricia F. , Bishop Allen T. , Shin Alexander Y. 
Published: July 2008

AbstractTetanic force measurements of rat tibialis anterior (TA) muscles have been described, but with a variety of stimulation parameters. This study presents a novel functional method of force measurement of the rat TA muscle and describes the optimization of stimulation parameters. Bilateral TA muscles in 10 male Lewis rats were attached to a force transducer after the corresponding hindlimb was fixed. Preload, stimulus intensity, duration, and frequency were optimized for each individual muscle and the isometric maximal tetanic muscle force was measured. The mean left side tetanic force as a percentage of the right was 100.0 ± 4.4% and was statistically equivalent. Large standard deviations between sides (35–50%) were observed in the optimized parameters (preload, stimulus intensity, duration, and frequency). Optimization of the variables affecting isometric tetanic force resulted in reproducible and reliable side‐to‐side measurements of the TA muscle in the rat model. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Neural cell transplantation effects on sciatic nerve regeneration after a standardized crush injury in the rat
Authors: Luís A. L. , Rodrigues J. M. , Geuna S. , Amado S. , Simões M. J. , Fregnan F. , Ferreira A. J. , Veloso A. P. , Armada‐Da‐Silva P. A. S. , Varejão A. S. P. , Maurício A. C. 
Published: July 2008

AbstractThe goal of the present study was to assess whether in vitro‐differentiated N1E‐115 cells supported by a collagen membrane would enhance rat sciatic nerve regeneration after a crush injury. To set up an appropriate experimental model for investigating the effects of neural cell transplantation, we have recently described the sequence of functional and morphologic changes occurring after a standardized sciatic nerve crush injury with a nonserrated clamp. Functional recovery was evaluated using the sciatic functional index, the static sciatic index, the extensor postural thrust, the withdrawal reflex latency, and ankle kinematics. In addition, histomorphometric analysis was carried out on regenerated nerve fibers by means of the 2D‐disector method. Based on the results of the EPT and of some of the ankle locomotor kinematic parameters analyzed, the hypothesis that N1E‐115 cells may enhance nerve regeneration is partially supported although histomorphometry disclosed no significant difference in nerve fiber regeneration between the different experimental groups. Therefore, results suggest that enrichment of equine type III collagen membrane with the N1E‐115 cellular system in the rat sciatic nerve crush model may support recovery, at least in terms of motor function. The discrepancy between functional and morphological results also suggests that the combined use of functional and morphological analysis should be recommended for an overall assessment of recovery in nerve regeneration studies. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Use of the venous flap for salvage of difficult ring avulsion injuries
Authors: Brooks Darrell , Buntic Rudolf F. , Taylor Chris 
Published: July 2008

AbstractRing avulsion can lead to soft tissue compromise resulting in eventual digit failure or restriction of motion. The authors present use of the venous flow through flap for simultaneous soft tissue and digital vessel reconstruction in severe ring avulsion injury. A retrospective review of ring avulsion injuries treated with transplantation of an arterialized (A‐V‐A) venous flap between 1999 and 2006 was conducted. Indications included digits which were debrided and required soft tissue and digital artery reconstruction. Eight venous flaps were transplanted for 3 Urbaniak class II and 5 Urbaniak class III ring avulsions. Average size of the venous flap was 6 cm2. All flaps and digits survived without partial necrosis. The soft tissue envelope was supple in all cases. Total active motion (TAM) ranged from 160 to 210°. The arterialized venous flow‐through flap is a reliable solution for the complex ring avulsion injury which requires simultaneous soft tissue and digital vessel reconstruction. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
An approximation to the solution of telegraph equation by variational iteration method
Authors: Biazar J. , Ebrahimi H. , Ayati Z. 
Published: July 2008

AbstractThe variational iteration method (VIM) has been applied to solve many functional equations. In this article, this method is applied to obtain an approximate solution for the Telegraph equation. Some examples are presented to show the ability of the proposed method. The results of applying VIM are exactly the same as those obtained by Adomian decomposition method. It seems less computation is needed in proposed method.© 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Die Bedeutung der Mutterkorn‐Alkaloide als Arzneistoffe. Weit mehr als nur α‐Blocker
Authors: Sinz Andrea 
Published: July 2008

AbstractMutterkorn‐Alkaloide und ihre an der Δ9,10‐Doppelbindung hydrierten Derivate besitzen als α‐Blocker nur noch geringe therapeutische Bedeutung, da sie partielle Antagonisten und partielle Agonisten an α‐Adrenozeptoren darstellen. Daher finden sie in den aktuellen Leitlinien zur Behandlung der arteriellen Hypertonie der Deutschen Hochdruckliga e. V. (Deutsche Hypertonie Gesellschaft) keine Erwähnung. Da Mutterkorn‐Alkaloide zusätzlich zu α‐Adrenozeptoren auch an 5‐HT‐Rezeptoren und Dopaminrezeptoren angreifen, finden sie Anwendung als Migränetherapeutika, bei Morbus Parkinson und in der Therapie der Altersdemenz. Allerdings werden die Mutterkorn‐Alkaloide auch im Bereich der Migränetherapie zunehmend von den Triptanen in den Hintergrund gedrängt. Es bleibt abzuwarten, wie sich die Anwendung der Mutterkorn‐Alkaloide in den nächsten Jahren entwickeln wird und ob sie sich als so genannte “dirty drugs” auf dem Markt werden behaupten können.
Current practice perspectives on the management of thrombosis in children with renal insufficiency: The results of a survey of pediatric hematologists in North America
Authors: Sharathkumar Anjali Alatkar 
Published: July 2008

AbstractBackgroundNo guidelines exist for the management of venous thromboembolic events (VTE) in children with renal insufficiency (RI).ObjectiveTo define current practice patterns of VTE management in children with RI.MethodsAn online multiple choice survey encompassing general questions/clinical scenarios related to thrombosis in RI. Study participants: Pediatric hematologists who were members of Hemophilia and Thrombosis Research Society (HTRS) of North America.ResultsResponse rate was 54% (39/75). VTE was perceived as the major hemostatic problem in children with RI by half (20/39) of respondents. All respondents used anticoagulation for treatment of VTE while 56% used it for prophylaxis of VTE in this population. Management practices varied with respect to choice of anticoagulants employed, consideration of prophylactic anticoagulation, and evaluation for hereditary thrombophilia. Low molecular weight heparin was perceived as a safe anticoagulation for VTE treatment by 77% of respondents given that anti‐factor Xa monitoring was performed to assess bioaccumulation in RI. Thromboprophylaxis was considered for preventing thrombosis at central venous catheter, renal allo‐graft and arterio‐venous fistula in the context of previous history of thrombosis and congenital/acquired thrombophilia. The majority (>70%) would treat life‐threatening emergencies such as superior vena cava syndrome with fibrinolytics despite RI.ConclusionsThis pediatric study documents that substantial variability existed among pediatric hemologists with respect to VTE management in children with RI. Larger studies are required to better define the epidemiology and management of VTE in children with RI including the value of screening for underlying hereditary thrombophilia. Pediatr Blood Cancer 2008;51:657–661. © 2008 Wiley‐Liss, Inc.
JAK2 V617F positive polycythemia Vera in a child with neurofibromatosis type I
Authors: Berman Jason N. , Greer Wenda L. , Archambeault Sophie , Loh Mignon L. , Riddell Christie , Morash Barbara , Dumas Nadine , Fernandez Conrad V. , Ludman Mark D. 
Published: July 2008

AbstractWe report a child with polycythemia vera (PV). This patient demonstrates the acquired somatic JAK2 V617F mutation and also has neurofibromatosis type I (NF1). NF1, while not previously associated with PV, is associated with another childhood MPD, juvenile myelomonocytic leukemia (JMML). Thus we examined a number of genetic abnormalities identified in JMML patients, but found no association in this case. Neurofibromin sequencing failed to identify a causative mutation. An unknown genetic abnormality resulting in NF1 may have predisposed this young child to acquiring the common JAK2 mutation. Pediatr Blood Cancer 2008;51:689–691. © 2008 Wiley‐Liss, Inc.
Increased serum monocyte chemoattractant protein‐1, macrophage inflammatory protein‐1β, and interleukin‐8 concentrations in hemophagocytic lymphohistiocytosis
Authors: Tamura Kazushi , Kanazawa Takashi , Tsukada Shota , Kobayashi Tohru , Kawamura Machiko , Morikawa Akihiro 
Published: July 2008

AbstractBackgroundHemophagocytic lymphohistiocytosis (HLH) is characterized by hypercytokinemia caused by macrophage and T cell activation. We analyzed the serum concentrations of monocyte chemoattractant protein (MCP)‐1, macrophage inflammatory protein (MIP)‐1β, and interleukin (IL)‐8 to investigate the roles of these chemokines in the pathophysiology of HLH.MethodsSeven patients clinically diagnosed with HLH were examined. Serum cytokines and chemokines were measured. The differences in the serum concentrations between the patients with HLH and the controls were investigated.ResultsIn patients with an active phase of HLH, the serum MCP‐1, MIP‐1β, and IL‐8 levels all were significantly higher than in healthy controls. The chemokine elevations decreased rapidly after initiation of chemotherapy. During increases in disease activity, elevation of MCP‐1 and MIP‐1β preceded elevation of the serum ferritin level, which is a clinical indicator of HLH disease activity.ConclusionsThese results suggest that MCP‐1, MIP‐1β, and IL‐8 play important roles in the pathophysiology of HLH. In addition, the serum concentrations of these chemokines may be sensitive markers for assessing disease activity in patients with HLH. Pediatr Blood Cancer 2008;51:662–668. © 2008 Wiley‐Liss, Inc.