bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Discovery of NBI‐77860/GSK561679, a Potent Corticotropin‐Releasing Factor (CRF1) Receptor Antagonist with Improved Pharmacokinetic Properties.
Authors: Williams John P. , et al. et al.
Published: March 2011

Among a variety of antagonists, the title compound (I) is found to be a high affinity ligand in the in vitro CRF ACTH production assay.
ChemInform Abstract: The Identification of Novel Orally Active mGluR5 Antagonist GSK2210875.
Authors: Watson Stephen , et al. et al.
Published: March 2011

The title antagonist (I) shows excellent bioavailability in rats and demonstrates excellent brain exposure.
ChemInform Abstract: Three‐Coordinate [Pt(N,N′‐Chelate)(η2‐olefin)] Complexes: Synthesis, Properties and Reactions with Electrophiles
Authors: Cucciolito Maria Elena , De Felice Vincenzo , Roviello Giuseppina , Ruffo Francesco
Published: March 2011

Review: 46 refs.
ChemInform Abstract: Soft Template Synthesis of Fe(II,III), Co(II,III), Ni(II) and Cu(II) Metalmacrocyclic Compounds in Gelatin‐Immobilized Matrix Implants
Authors: Mikhailov Oleg V.
Published: March 2011

Review: 148 refs.
ChemInform Abstract: Palladium‐Catalyzed Synthesis of N‐ and O‐Heterocycles Starting from Enol Phosphates
Authors: Fuwa Haruhiko
Published: March 2011

Review: about 150 refs.
ChemInform Abstract: Mechanisms in Aminocatalysis
Authors: Nielsen Martin , Worgull Dennis , Zweifel Theo , Gschwend Bjoern , Bertelsen Soeren , Joergensen Karl Anker
Published: March 2011

Review: 71 refs.
ChemInform Abstract: New Synthetic Reactions Using Conjugate Addition Reactions of Nucleophiles to α,β‐Unsaturated Imines
Authors: Hachiya Iwao , Shimizu Makoto
Published: March 2011

Review: ca. 50 refs.
ChemInform Abstract: Modular Synthesis of Organic Electronic Materials
Authors: Tsuji Hayato
Published: March 2011

Review: ca. 50 refs.
ChemInform Abstract: Catalytic Oxidation of Carbon Monoxide over Transition Metal Oxides
Authors: Royer Sebastien , Duprez Daniel
Published: March 2011

Review: 403 refs.
ChemInform Abstract: Medium‐Bridged Lactams: A New Class of Non‐Planar Amides
Authors: Szostak Michal , Aube Jeffrey
Published: March 2011

Review: about 50 refs.
ChemInform Abstract: Graphene Oxide as Catalyst: Application of Carbon Materials Beyond Nanotechnology
Authors: Pyun Jeffrey
Published: March 2011

Review: 23 refs.
ChemInform Abstract: Catalytic Organometallic Reactions of Ammonia
Authors: Klinkenberg Jessica L. , Hartwig John F.
Published: March 2011

Review: 51 refs.
ChemInform Abstract: Colloidal Assembly: The Road from Particles to Colloidal Molecules and Crystals
Authors: Li Fan , Josephson David P. , Stein Andreas
Published: March 2011

Review: 219 refs.
ChemInform Abstract: Gold Nanostructures: A Class of Multifunctional Materials for Biomedical Applications
Authors: Cobley Claire M. , Chen Jingyi , Cho Eun Chul , Wang Lihong V. , Xia Younan
Published: March 2011

Review: 63 refs.
ChemInform Abstract: Dynamic Interplay Between Histone H3 Modifications and Protein Interpreters: Emerging Evidence for a “Histone Language”
Authors: Oliver Samuel S. , Denu John M.
Published: March 2011

Review: 99 refs.
ChemInform Abstract: Aromaticity and Chemical Reactivity
Authors: Matito Eduard , Poater Jordi , Sola Miquel , von Rague Schleyer Paul
Published: March 2011

Review: 149 refs.
ChemInform Abstract: Identifying Reaction Intermediates and Catalytic Active Sites Through in situ Characterization Techniques
Authors: Foster Andrew J. , Lobo Raul F.
Published: March 2011

Review: 71 refs.
ChemInform Abstract: In situ Study on Molecular Diffusion Phenomena in Nanoporous Catalytic Solids
Authors: Chmelik Christian , Kaerger Joerg
Published: March 2011

Review: 169 refs.
ChemInform Abstract: Chiral Separation by Enantioselective Liquid—Liquid Extraction
Authors: Schuur Boelo , Verkuijl Bastiaan J. V. , Minnaard Adriaan J. , de Vries Johannes G. , Heeres Hero J. , Feringa Ben L.
Published: March 2011

Review: 168 refs.
Assessment of mixing quality for an industrial pulp mixer using electrical resistance tomography
Authors: Yenjaichon Wisarn , Pageau Gerry , Bhole Manish , Bennington Chad P. J. , Grace John R.
Published: March 2011

The quality of mixing of a pulp suspension and chlorine dioxide by a static mixer in an industrial chlorine dioxide bleaching stage was evaluated using electrical resistance tomography (ERT) as a function of process operating conditions, including chemical flow rate, suspension flow rate, and suspension mass concentration. The uniformity was quantified by a mixing index based on the coefficient of variation of the individual conductivity values in each image pixel. An increase in the mixing index, indicating lower mixing quality, was observed when the chemical flow rate increased. In addition, the mixing quality decreased with a decrease in suspension flow rate. On the other hand, a decrease in the suspension mass concentration at a constant volumetric suspension flow rate gave better mixing quality. The results show that ERT can be used to evaluate industrial‐scale mixer performance and to monitor the changes in the mixing quality as a function of process operating conditions. The results are in good agreement with those in the literature based on other measurement techniques for similar mixer installations.
Nanoparticulate Hollow TiO2 Fibers as Light Scatterers in Dye‐Sensitized Solar Cells: Layer‐by‐Layer Self‐Assembly Parameters and Mechanism
Authors: Rahman Masoud , Tajabadi Fariba , Shooshtari Leyla , Taghavinia Nima
Published: March 2011

Hollow structures show both light scattering and light trapping, which makes them promising for dye‐sensitized solar cell (DSSC) applications. In this work, nanoparticulate hollow TiO2 fibers are prepared by layer‐by‐layer (LbL) self‐assembly deposition of TiO2 nanoparticles on natural cellulose fibers as template, followed by thermal removal of the template. The effect of LbL parameters such as the type and molecular weight of polyelectrolyte, number of dip cycles, and the TiO2 dispersion (amorphous or crystalline sol) are investigated. LbL deposition with weak polyelectrolytes (polyethylenimine, PEI) gives greater nanoparticle deposition yield compared to strong polyelectrolytes (poly(diallyldimethylammonium chloride), PDDA). Decreasing the molecular weight of the polyelectrolyte results in more deposition of nanoparticles in each dip cycle with narrower pore size distribution. Fibers prepared by the deposition of crystalline TiO2 nanoparticles show higher surface area and higher pore volume than amorphous nanoparticles. Scattering coefficients and backscattering properties of fibers are investigated and compared with those of commercial P25 nanoparticles. Composite P25–fiber films are electrophoretically deposited and employed as the photoanode in DSSC. Photoelectrochemical measurements showed an increase of around 50 % in conversion efficiency. By employing the intensity‐modulated photovoltage and photocurrent spectroscopy methods, it is shown that the performance improvement due to addition of fibers is mostly due to the increase in light‐harvesting efficiency. The high surface area due to the nanoparticulate structure and strong light harvesting due to the hollow structure make these fibers promising scatterers in DSSCs.
Mucinous adenocarcinoma of rectum in an 11‐year‐old boy: A case report
Authors: Agrawal Pallavi , Rajwanshi Arvind , Gupta Nalini , Rao K. L. N.
Published: March 2011

Colorectal carcinoma in pediatric population is relatively rare (<1% of all cancers in first two decades) and behaves aggressively as compared with the same in adult population. We report a case of 11‐year‐old adolescent male, who presented with pain abdomen and melena. Fine‐needle aspiration cytology from the growth in rectum revealed mucinous adenocarcinomas, which was later confirmed on histopathology. The patient also had positive peritoneal fluid cytology. Diagn. Cytopathol. 2012 © 2011 Wiley Periodicals, Inc.
Synthesis of 5‐(Fluorophenyl)tocopherols as Novel Dioxin Receptor Antagonists
Authors: Kloser Elisabeth , Böhmdorfer Stefan , Brecker Lothar , Kählig Hanspeter , Netscher Thomas , Mereiter Kurt , Rosenau Thomas
Published: March 2011

γ‐Tocopherol, a component of the essential nutrient mixture commonly designated as vitamin E, was chemically combined with differently substituted monofluoro‐ and difluorophenyl moieties to produce potential antagonists for the human aryl hydrocarbon receptor (AhR). 5‐Iodo‐γ‐tocopherol was a very reliable starting material for the Pd‐catalyzed reaction with (fluorophenyl)boronic acids (Suzuki coupling). The ortho‐ and meta‐fluoro‐substituted derivatives showed conformational isomerism due to restricted rotation around the interaromatic bond. This effect was investigated by NMR spectroscopy. Three of the derivatives showed very high potency in assays and are promising candidates for further testing.
Exploring the Relationship between Coping Strategies and Binge Eating in Nonclinical Adolescents
Authors: Sierra‐Baigrie Susana , Lemos‐Giráldez Serafín , Paino Mercedes , Fonseca‐Pedrero Eduardo
Published: March 2011

The aims of the study were to determine the rate of binge eating and examine the relationship between binge eating and coping in nonclinical adolescents. A total of 1913 adolescents completed the Bulimic Investigatory Test, Edinburgh, the Adolescent Coping Scale (ACS), the Youth Self‐Report and additional questions regarding the binge‐eating episodes. Of the total sample, 6.94% reported bingeing in the last 6 months. The adolescents who binge eat reported a more frequent use of Intropunitive avoidance and Introversion and a less frequent use of Positive‐effortful coping compared with those who do not binge eat. However, when the effects of age and depression were controlled in the analysis, the groups only differed in the Positive and Intropunitive avoidance dimensions of coping. Training adolescents on how to cope with stress in a more constructive manner may be a possible strategy for the prevention of maladaptive eating patterns in adolescents. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.
Moisture content in timber decking exposed to bushfire weather conditions
Authors: Macindoe Lyndon , Leonard Justin
Published: March 2011

Ignition of the external combustible elements of a building is one of the key factors leading to house loss in bushfires. Timber elements contain moisture that migrates into and out from the timber surface, depending on the surrounding ambient conditions. In extreme hot and dry conditions, such as those associated with severe bushfire weather, the moisture contents (MCs) in building timbers can drop well below the normal levels. In this paper, we not only qualify a methodology to assess the likely MCs of timbers under typical bushfire conditions, but also quantify the low levels of moisture that can be expected for the climatic conditions experienced in Melbourne—one of Australia's bushfire‐prone regions. Copyright © 2011 John Wiley & Sons, Ltd.
Investigating evacuation lift dispatch strategies using computer modelling
Authors: Kinsey Michael J. , Galea Edwin R. , Lawrence Peter J.
Published: March 2011

This paper presents a detailed description of an agent‐based lift (elevator) model developed within buildingEXODUS software intended to represent evacuation scenarios. The main components of the lift model are described including the lift: kinematics, attributes and dispatch control. The agent–lift interaction model is also described, including the lift bank selection, the lift waiting area behaviour (wait location selection and wait duration) and the lift car selection and entry. The lift model is used to investigate a series of full building evacuation scenarios based on a hypothetical 50 floor building with four staircases and a population of 7840 agents. The analysis explores the relative merits of using up to 32 lifts (arranged in four banks) and various egress lift dispatch strategies to evacuate the entire building population. Findings from the investigation suggest that the most efficient evacuation strategy utilizes a combination of lifts and stairs to empty the building and clear the upper half of the building in minimum time. Combined stair lift evacuation times have been shown to be as much as 50% faster than stair only evacuation times. The introduction of the agent milling behaviour resulted in reductions in evacuation times compared with the same scenarios without milling behaviour. Copyright © 2011 John Wiley & Sons, Ltd.
Are speculators informed?
Authors: Schwarz Krista
Published: March 2011

The positions of hedgers and speculators are correlated with returns in a number of futures markets, but there is much debate as to the interpretation of such a relationship—whether it reflects private information, liquidity, or trend‐chasing behavior. This paper studies the relationship between positioning of hedgers and speculators and returns in equity futures markets. I propose a novel test of the private information hypothesis: analyzing the effect of public announcements about futures positions on prices, using high‐frequency data in short windows around the announcements. I find that the revelation of speculators' positions is informative to investors more broadly, supporting the private information view. © 2011 Wiley Periodicals, Inc. Jrl Fut Mark
Functional outcomes related to the prevention of radiation‐induced xerostomia: Oral pilocarpine versus submandibular salivary gland transfer
Authors: Rieger Jana M. , Jha Naresh , Lam Tang Judith A. , Harris Jeffrey , Seikaly Hadi
Published: March 2011

Background

Xerostomia has a devastating impact on oral function and quality of life in patients who receive radiation treatment for head and neck cancer. The purpose of this study was to examine functional outcomes related to 2 saliva‐sparing treatments: (1) oral pilocarpine during radiotherapy; or (2) the submandibular salivary gland transfer (SGT) before radiotherapy.

Methods

Sixty‐nine patients were recruited (SGT = 36; pilocarpine = 33). Speech intelligibility, swallowing outcomes, and quality of life were assessed at 4 points in time (pretreatment, and 1 month, 6 months, and 12 months after the pretreatment assessment).

Results

There were no differences between groups in speech outcomes; however, significant between‐group differences existed in swallowing and quality of life outcomes. In all cases, patients who received the SGT procedure had better swallowing outcomes and quality of life scores than the patients who received oral pilocarpine.

Conclusion

The SGT should be the treatment of choice between the 2 treatments offered to prevent xerostomia in the present study. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Voice, swallowing, and quality of life after total laryngectomy—Results of the west of Scotland laryngectomy audit
Authors: Robertson Stuart M. , Yeo Justin C. L. , Dunnet Catherine , Young David , MacKenzie Kenneth
Published: March 2011

Background

The purpose of this study was to determine the effects of radiotherapy and surgical voice restoration on functional outcome after total laryngectomy.

Methods

Questionnaire packs were posted to all 258 laryngectomy patients in the West of Scotland Managed Clinical Network. Packs contained the Voice Symptom Scale (VoiSS), MD Anderson Dysphagia Inventory (MDADI), and University of Washington Quality of Life Questionnaire (UW‐QOL).

Results

Significantly better VoiSS and MDADI scores were reported by patients undergoing laryngectomy alone in comparison with patients receiving adjuvant radiotherapy and patients undergoing salvage laryngectomy (p < .02). Patients using tracheoesophageal voice reported significantly better VoiSS scores than patients using other communication methods (p < .005).

Conclusion

Radiotherapy has a highly significant and detrimental effect on voice and swallowing outcome after total laryngectomy. Surgical voice restoration confers significant benefit in terms of self‐reported voice outcome. These findings have implications for patients with advanced laryngeal cancer considering laryngectomy and organ preservation. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Closure of laryngectomy defects in the age of chemoradiation therapy
Authors: Hanasono Matthew M. , Lin Derrick , Wax Mark K. , Rosenthal Eben L.
Published: March 2011

The use of chemoradiation therapy in laryngeal cancer has resulted in significant reconstructive challenges. Although reconstruction of salvage laryngectomy defects remains controversial, current literature supports aggressive management of these defects with vascularized tissue, even when there is sufficient pharyngeal tissue present for primary closure. Significant advancement in reconstructive techniques has permitted improved outcomes in patients with advanced disease who require total laryngopharyngectomy or total laryngoglossectomy. Use of enteric and fasciocutaneous flaps result in good patient outcomes. Finally, wound complication rates after salvage surgery approach 60% depending on comorbid conditions such as cardiac insufficiency, hypothyroidism, or extent of previous treatment. Neck dehiscence, great vessel exposure, fistula formation, or cervical skin necrosis results in complex wounds that can often be treated initially with negative pressure dressings followed by definitive reconstruction. The timing of repair and approach to the vessel‐depleted neck also present challenges in this patient population. Currently, there is significant institutional bias in the management of the patient with postchemoradiation salvage laryngectomy. Future prospective multi‐institutional studies are certainly needed to more clearly define optimal treatment of these difficult patients. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
The activity of aminoacyl‐tRNA synthetase‐interacting multi‐functional protein 1 (AIMP1) on endothelial cells is mediated by the assembly of a cytoskeletal protein complex
Authors: Jackson Valentina Charlotte , Dewilde Sarah , Albo Alessandra Giuliano , Lis Katarzyna , Corpillo Davide , Canepa Barbara
Published: March 2011

AIMP1 was first found as a factor associated with the aminoacyl‐tRNA synthetase (ARS) complex. However, it is also secreted and acts on different target cells such as endothelial cells, macrophages, and fibroblasts as an extracellular regulator, respectively, of angiogenesis, inflammatory responses and dermal regeneration. AIMP1 has also been reported to suppress in vivo tumor growth. In this study, we investigated the signaling pathways activated by exogenous AIMP1 in an in vitro endothelial model. AIMP1 decreases EC viability through an α5β1 integrin‐dependent mechanism and inhibits cell adhesion, is internalized and shows an asymmetric pattern of distribution and accumulation in cell protrusions. Experiments of affinity purification, pull down, and co‐immunoprecipitation showed that AIMP1 interacts with four cytoskeletal proteins (filamin‐A, α‐tubulin, vinculin, and cingulin). α‐Tubulin also gets phosphorylated upon cell treatment with AIMP1 and colocalization between AIMP1 and filamin‐A as well as between AIMP1 and cingulin was observed through immunofluorescence assays. In this work, we propose that AIMP1 effect on EC adhesion is mediated by the assembly of a cytoskeletal protein complex on the cytosolic face of the cell membrane which could regulate cellular architecture maintenance and remodeling. Moreover, this activity is able to indirectly influence cell viability. J. Cell. Biochem. 112: 1857–1868, 2011. © 2011 Wiley‐Liss, Inc.
Observational and supportive modelling analyses of winter precipitation change in China over the last half century
Authors: Gillies Robert R. , Wang Shih‐Yu , Huang Wan‐Ru
Published: March 2011

Overall increasing trends in annual precipitation and widespread warming over China have been documented. During the winter months in southeast China, where snow is commonplace but rarely accumulates, the climatological 0 °C surface isotherm generally defines the southern boundary of the snowfield. Therefore, a warming climate will: (a) modify the southern boundary of the snowfield; and (b) potentially alter the snow‐rain ratio. Using recently released daily precipitation from the Asian Precipitation‐Highly Resolved Observational Data Integration Towards Evaluation (APHRODITE) and temperature observations from the ERA‐40/Interim Reanalyses, this study investigated historical winter precipitation changes in China. Since snowfall observations were largely unavailable for southeast China, snowfall amounts were estimated using a rain‐snow threshold temperature (RST) method which was subsequently verified by in situ and satellite observations of snow depth, snow cover, and snow water equivalent (SWE). The composite analysis reveals a decrease in snowfall totals which are accompanied by an increase in rainfall; this change corresponds with the northward retreat of the 0 °C surface isotherm and the snow‐rain ratio. Atmospheric circulation analysis indicated lower tropospheric warming with increased moisture over southeast China, consistent with previous studies. Moreover, we observed an increase in the convergence of water vapour flux which sustains the increase in precipitation; this is accompanied by the suppression of snowfall due to the lower tropospheric warming. An additional analysis employed to further substantiate the RST method was undertaken by modelling the snow‐rain ratio with the Weather Research and Forecasting (WRF) Model. The results were in agreement with those estimated from the observations. Copyright © 2011 Royal Meteorological Society
Bone stresses before and after insertion of two commercially available distal ulnar implants using finite element analysis
Authors: Austman Rebecca L. , King Graham J.W. , Dunning Cynthia E.
Published: March 2011

Distal ulnar arthroplasty is becoming a popular treatment option for disorders of the distal radioulnar joint; however, few studies have investigated how load transfer in the ulna is altered after insertion of an implant. The purpose of our study was to compare bone stresses before and after insertion of two commercially available cemented distal ulnar implants: an implant with a titanium stem and an implant with a cobalt chrome stem. Appropriately sized implants of both types were inserted into eight previously validated subject‐specific finite element models, which were created by using information derived from computed tomography scans. The von Mises stresses were compared at eight different regions pre‐ and post‐implantation. The bone stresses with the titanium stem were consistently closer to the pre‐implantation stresses than with the cobalt chrome stem. For the loading situation and parameters investigated, results of these models show that insertion of the E‐Centrix® ulnar Head may result in less stress shielding than the SBI uHead™ stem. Future studies are required to investigate other implant design parameters and loading conditions that may affect the predicted amount of stress shielding. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1418–1423, 2011
Micro‐Raman investigation of nanosized zinc ferrite: effect of crystallite size and fluence of irradiation
Authors: Singh Jitendra Pal , Srivastava R. C. , Agrawal H. M. , Kumar Ravi
Published: March 2011

Zinc ferrite nanoparticles of different sizes ranging from 12 to 62 nm were synthesized by using the nitrate route. These nanoparticles were irradiated by a 100 MeV oxygen beam at two fluences: 1 × 1013 and 5 × 1013 ions/cm2. It was observed that modes corresponding to cubic spinel phase were retained after the irradiation in all the systems. The variation in the parameters of various modes follows phonon confinement, while this effect seems to violate in irradiated specimen. It was found that the irradiation‐induced changes in the modes F2g(2) and F2g(3) depend on whether the crystallite size of the pristine sample is less than, equal to or greater than the phonon confinement length, while this length is not dominant for the irradiation‐induced changes in the mode A1g. The changes in various parameters of the modes are attributed to the combined effect of the restructuring of the chemical species and ion‐induced defects. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of Rotaxane Formation on the Photophysical, Morphological, and Adhesion Properties of Poly[2,7‐(9,9‐dioctylfluorene)‐alt‐(5,5'‐bithiophene)] Main‐Chain Polyrotaxanes
Authors: Farcas Aurica , Ghosh Indrajit , Grigoras Vasile C. , Stoica Iuliana , Peptu Cristian , Nau Werner M.
Published: March 2011

In order to investigate the effect of rotaxane formation on the photophysical and morphological properties of π‐conjugated materials, a new main chain polyrotaxane was synthesized through Suzuki coupling between the inclusion complex of 5,5'‐dibromo‐2,2'‐bithiophene with randomly methylated β‐cyclodextrin and 9,9‐dioctylfluorene‐2,7‐trimethylene diborate. Due to rotaxane formation, a blue shift in the absorption spectra as well as in the fluorescence spectra was observed, while the fluorescence quantum yields and fluorescence lifetimes remained unchanged. This study demonstrates that rotaxane formation can alter the electronic and morphological properties of the threaded copolymer, which is of great interest for electronic applications.

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Nanocomposites with Biodegradable Polycaprolactone Matrix
Authors: Janigová Ivica , Lednický František , Mošková Daniela Jochec , Chodák Ivan
Published: March 2011

Summary: Biodegradable polymer/clay nanocomposites and/or composites based on poly(ε‐polycaprolactone) (PCL) were prepared by conventional melt mixing. Three kinds of clays, organomodified Cloisite 15A and Cloisite 10A with different ammonium cations located in the silicate gallery and unmodified Cloisite with Na cations were used for composites preparation. The degree of dispersion of silicate layers in the matrix was determined by X‐ray diffraction and transmission electron microscopy. Oscillatory rheological measurements were used for characterization of the physical network formed by the filler. The presence of intercalated and exfoliated structures were observed for the composites PCL/Cloisite 15A and PCL/Cloisite 10A, indicating that nanocomposite structure was formed. Changes of viscoelastic properties to more solid‐like behavior, especially in the low frequency range were explained by formation of silicate network structure, which can be detected by modified Cole‐Cole plots.
Reprocessed High Impact Polypropylene Containing Oil Pollutant Exhibiting Flame Retardant Properties
Authors: Casetta Mathilde , Delaval Damien , Traisnel Michel , Bourbigot Serge
Published: March 2011

Summary: In this work, the reaction to fire of reprocessed polypropylene (PP)/Ethylene Propylene Rubber (EPR) materials containing engine oil as pollutant was investigated by mass loss calorimetry. It was compared to the behaviour of the corresponding original high impact PP material. In order to flame retard the polymers, an intumescent system was studied in combination with zinc borate (ZB) as potential synergistic agent. It is shown that 20% of additives are necessary to obtain good FR properties. The use of ZB greatly improves the reaction to fire of original PP/EPR materials due to the formation of borophosphates during the degradation process that permit to reinforce the char structure. In the case of the polluted and reprocessed formulations, ZB has no influence on the fire performance because the minerals included in the engine oil act also as a flame retardant. For the two types of materials, it is demonstrated that the expansion rate at the beginning of the intumescent process plays a crucial role in the formation of an efficient insulating layer at the surface of the substrate. On the contrary, the fire performance is not related to the thickness of the carbonaceous shield.
Comparative Properties of Thermoplastic Polyurethane Adhesive Filled with Natural or Precipitated Calcium Carbonate
Authors: Donate‐Robles Jessica , Martín‐Martínez José Miguel
Published: March 2011

Summary: The rheological, mechanical and adhesion properties of thermoplastic polyurethane adhesive (TPU) containing natural ultramicronized or precipitated nanometric calcium carbonate filler were compared. Precipitated calcium carbonate addition did not noticeably improve the rheological properties of filled TPU with respect to the effect produced by adding natural calcium carbonate. The precipitated calcium carbonate nanoparticles migrated to the TPU surface due to incompatibility between the filler and the polyurethane. The wettability of the filled TPU was reduced by adding natural calcium carbonate, but it was increased slightly by adding precipitated calcium carbonate. Finally, the immediate adhesive strength in PVC/TPU adhesive/PVC joints increased noticeably when the adhesive contained filler; however, the final adhesive strength was similar irrespective of the filler particle size.
Organo‐Montmorillonite as a Controlled Release Reservoir for Triclosan in Silicone Elastomer: A Flow Micro‐Calorimetry and Leaching Study
Authors: Liauw Christopher M. , Taylor Rebecca L. , Maryan Christopher , Kato Ryo , Wilkinson Arthur N. , Cheerarot Onanong
Published: March 2011

Summary: Organically modified montmorillonite (o‐MMT) in a room temperature addition cured silicone elastomer (PDMS) has been found to control the release of 2,4,2′‐trichloro‐2′‐hydroxy diphenylether (triclosan (TCS)) from the composite. The effect of o‐MMT gallery polarity on controlled release was investigated via different intercalants and the interaction of triclosan with the o‐MMT was investigated using flow micro‐calorimetry (FMC). The latter was found not to be a universal predictor of controlled release activity of the composite as combined TCS and PDMS interactions with MMT/o‐MMT leading to intercalation (observed using WAXS) and controlled release activity must also be considered. Southern Clay Products Cloisite® 15A (C15A) gave the most sustained release of TCS whilst also featuring a uniform gallery spacing in the composite. A pore structure based on self‐assembled C15A intercalant alkyl tails is tentatively proposed.
Polypropylene Nanocomposites, Study of the Influence of the Nanofiller Nature on Morphology and Material Properties
Authors: Tabuani D. , Ceccia S. , Camino G.
Published: March 2011

Summary: In this paper we investigate the influence of various nanofilllers' aspect ratio, chemical nature and organic modification on some selected polypropylene properties, such as crystallinity, thermal and mechanical resistance and fire behaviour. Materials were prepared by twin‐screw extrusion and characterized by means of scanning electron microscopy, X‐ray diffraction, thermogravimetric analysis, tensile and cone calorimeter tests. Fillers characteristics were found to influence at different extents, and for different reasons, the material final properties.
Processing and Final Properties Improvement of Polyolefin‐Sepiolite and Carbon Nanofibre Nanocomposites
Authors: La Tegola S. , Terenzi A. , Martini R. , Barbosa S. , Torre L. , Kenny José
Published: March 2011

Summary: In this work polypropylene (PP) nanocomposites with different nanofillers (sepiolites and carbon nanofibres) have been produced, processed by injection moulding and fibre spinning and analyzed in terms of mechanical properties improvements. Different concentrations of both fillers were used in nanocomposites preparation. The influence of nanofiller type and amount on mechanical properties were analyzed and discussed for each process studied. This study was completed with a basic morphological characterization in order analyze the nanofiller dispersion, distribution and orientation in the nanocomposites. The results achieved show that it is possible to obtain a good dispersion and distribution of the each kind of nanofillers with conventional processing methodologies when the nanofiller concentration is small. Moreover the nanocomposites obtained had better properties than the starting polymers, showing that sepiolite and carbon nanofiller are able to provide an important contribution to the improvement of mechanical properties of the materials analyzed, enlarging the final application possibilities of PP based products.
Quantitative Characterization of Clay Dispersion in Polymer‐Clay Nanocomposites
Authors: Xie Shaobo , Harkin‐Jones Eileen , Shen Yucai , Hill Janet , Hornsby Peter , McAfee Marion , McNally Tony , Patel Raj , Benkreira Hadj , Coates Phil
Published: March 2011

Summary: A novel methodology has been developed to describe the microstructure of polymer‐clay nanocomposites quantitatively. It builds on the image analyses of transmission electron microscopy and optical microscopy micrographs, and two parameters, degree of dispersion and mean interparticle distance per unit volume of clay, are proposed to characterize the level of clay dispersion. It provides insights into the ‘real’ clay dispersion using a combination of both microscopical and macroscopical aspects.
Prediction of Acute Rodent Toxicity on the Basis of Chemical Structure and Physicochemical Similarity
Authors: Raevsky O. A. , Grigor'ev V. Y. , Liplavskaya E. A. , Worth A. P.
Published: March 2011

A development of the Arithmetic Mean Toxicity (AMT) approach is presented in this article. Twenty six physicochemical descriptors, calculated by using the HYBOT program, along with molecular weight and lipophilicity were included in the selection of structural and physicochemical neighbours (analogues). Toxicity predictions of 906 chemicals from the REACH Pre‐Registration Substance (PRS) list were carried out with the application of six nearest structural neighbours and three pairs of structural/physicochemical neighbours on the basis of molecular polarizability, the sum of negative atomic charges in a molecule, the sum of H‐bond acceptor and donor factors and the octanol‐water partition coefficient. The best prediction results were obtained three pair structural neighbours were applied (each pair contains one chemical with a higher and one chemical with a lower descriptor value). The prediction of toxicity as the mean arithmetic toxicity value of the nearest structural and physicochemical neighbours can be considered a robust approach for the read‐across of properties (toxicity data) between analogues. Traditionally, analogues would be selected by expert judgement, but increasingly the availability of large databases and the application of nearest neighbour approaches such as the AMT approach provide a means of automating such assessments.
Predictivity of Simulated ADME AutoQSAR Models over Time
Authors: Rodgers Sarah L. , Davis Andrew M. , Tomkinson Nick P. , van de Waterbeemd Han
Published: March 2011

The automation of model building and model updating (autoQSAR) is an important step forward towards real‐time small molecule drug discovery project support using the latest experimental data. We present here a simulation study using real company data of the behaviour of QSAR models over time. Three different global QSAR models, namely, human plasma protein binding, aqueous solubility and log D7.4, are updated on a monthly basis over a period of three years. The effect of updating the models on their predictivity is studied using a series of monthly temporal test sets in addition to a final terminal temporal test set. Partial Least Squares (PLS), Random Forest (RF) and Bayesian Neural Networks (BNN) models are examined, covering three distinctly different approaches to QSAR modelling. It is demonstrated that the models are able to predict forward in time, but that updating models on a regular basis increases their ability to make predictions for current compounds. The degree of the improvement depends on the property studied and the model building technique used. These results demonstrate the importance of updating models on a regular basis. For both static models predicting forward in time, and regularly updating models it is shown that RF models are the most predictive for these data sets.
Associating Drugs, Targets and Clinical Outcomes into an Integrated Network Affords a New Platform for Computer‐Aided Drug Repurposing
Authors: Oprea Tudor I. , Nielsen Sonny Kim , Ursu Oleg , Yang Jeremy J. , Taboureau Olivier , Mathias Stephen L. , Kouskoumvekaki Irene , Sklar Larry A. , Bologa Cristian G.
Published: March 2011

Finding new uses for old drugs is a strategy embraced by the pharmaceutical industry, with increasing participation from the academic sector. Drug repurposing efforts focus on identifying novel modes of action, but not in a systematic manner. With intensive data mining and curation, we aim to apply bio‐ and cheminformatics tools using the DRUGS database, containing 3837 unique small molecules annotated on 1750 proteins. These are likely to serve as drug targets and antitargets (i.e., associated with side effects, SE). The academic community, the pharmaceutical sector and clinicians alike could benefit from an integrated, semantic‐web compliant computer‐aided drug repurposing (CADR) effort, one that would enable deep data mining of associations between approved drugs (D), targets (T), clinical outcomes (CO) and SE. We report preliminary results from text mining and multivariate statistics, based on 7684 approved drug labels, ADL (Dailymed) via text mining. From the ADL corresponding to 988 unique drugs, the “adverse reactions” section was mapped onto 174 SE, then clustered via principal component analysis into a 5×5 self‐organizing map that was integrated into a Cytoscape network of SE‐D‐T‐CO. This type of data can be used to streamline drug repurposing and may result in novel insights that can lead to the identification of novel drug actions.
Exact algorithms for the vertex separator problem in graphs
Authors: de Souza Cid C. , Cavalcante Victor F.
Published: March 2011

In this article, we propose a Lagrangian relaxation framework to solve the vertex separator problem (VSP). This framework is based on the development of relax‐and‐cut algorithms which embed the separation of valid inequalities for the VSP discussed by Balas and de Souza (Math Program 103 (2005), 583–608) in the subgradient method. These relax‐and‐cut algorithms are then used as a preprocessing phase in a hybrid algorithm which combines them with branch‐and‐cut algorithms proposed by de Souza and Balas (Math Program 103 (2005), 609–631). This is done basically by feeding the branch‐and‐cut algorithms not only with the primal bound but also the cuts separated during the preprocessing phase. Computational results obtained with benchmarks from the literature showed that the hybrid algorithm developed here outperforms the best exact algorithm available for the VSP to date. © 2011 Wiley Periodicals, Inc. NETWORKS, 2011
Shape optimization of shell structures based on NURBS description using automatic differentiation
Authors: Espath L. F. R. , Linn R. V. , Awruch A. M.
Published: March 2011

The consolidation of the link among four fields in computational mathematics and mechanics is the main objective of this work. Surfaces based on NURBS (non‐uniform rational B‐spline), mathematical optimization, the finite element method (FEM) in structural analysis, and automatic differentiation (AD) are applied in shape optimization of shells. This problem is performed taking into account the fact that material and mechanical characteristics influence both, the structural shape and the thickness variation, in order to obtain the best performance with respect to a specific criterium. Some techniques were implemented to modify the shell geometry conserving the same parameterization without a new finite element mesh generation. The shape modification is carried out using an optimization code based on the data obtained by a finite element analysis and gradients evaluation. In this work the optimization procedure is performed using an SQP (Sequential Quadratic Programming) algorithm, where the variables are the control points in homogeneous coordinates, the knot vectors, and the thickness. The functional value is determined by the FEM and gradients are evaluated using AD. Some examples are analyzed and discussed. As a consequence of the shape optimization, shells with high structural performance and aesthetically beautiful shapes can be obtained. Copyright © 2011 John Wiley & Sons, Ltd.
Knowledge and health beliefs of Jamaican adolescents with sickle cell disease
Authors: Bhatt Komal , Reid Marvin E. , Lewis Norma A. , Asnani Monika R.
Published: March 2011

Background

The adolescent stage of life is generally perceived to be a challenging period, which may be magnified when a chronic illness such as sickle cell disease (SCD) is present. In this study, we sought to determine the knowledge and health beliefs of Jamaican adolescents with SCD as these factors may impact their self‐management skills.

Procedure

An interviewer‐administered questionnaire was completed by 117 patients (93 SS:24 SC; 48 males:69 females) between the ages of 15 and 19 years at their routine health maintenance visit to the Sickle Cell Unit, UWI. A maximum total score of 17 could be attained for knowledge. The health belief questions were assessed using a 5‐point Likert scale and correlations between knowledge and health beliefs were done. Multiple regression models were created to study the predictors of knowledge and health belief scores. The study was granted ethical approval by UWI/UHWI Ethics Committee.

Results

The mean knowledge score was 64% (range 88–29%). No differences were found in the mean knowledge scores between genotypes and educational attainment but females appeared to score higher than males (P‐value <0.05). Most adolescents perceived SCD to be a severe illness and thought it is important for people to know their SCD status. However, almost 30% thought their partners would be hard to convince for testing. Higher knowledge scores predicted positive health beliefs in the adolescent.

Conclusions

Whereas most adolescents were knowledgeable about how the disease was inherited and tested for, further education especially about disease and pregnancy complications is needed. Pediatr Blood Cancer 2011; 57: 1044–1048. © 2011 Wiley‐Liss, Inc.
Self‐assembly and secondary structures of linear polypeptides tethered to polyhedral oligomeric silsesquioxane nanoparticles through click chemistry
Authors: Lin Yung‐Chih , Kuo Shiao‐Wei
Published: March 2011

In this study, we used click chemistry to synthesize a new macromolecular self‐assembling building blocks, linear polypeptide‐b‐polyhedral oligomeric silsesquioxane (POSS) copolymers, from a mono‐azido–functionalized POSS (N3‐POSS) and several alkyne‐poly(γ‐benzyl‐L‐glutamate) (alkyne‐PBLG) systems. The incorporation of the POSS unit at the chain end of the PBLG moiety allowed intramolecular hydrogen bonding to occur between the POSS and PBLG units, thereby enhancing the α‐helical conformation in the solid state, as determined through Fourier transform infrared spectroscopy and wide‐angle X‐ray diffraction analyses. POSS‐b‐PBLG underwent hierarchical self‐assembly, characterized using small‐angle X‐ray scattering, to form a bilayer‐like nanostructure featuring α‐helical or β‐sheet conformations and POSS aggregates. Thermogravimetric analysis indicated that the thermal degradation temperature increased significantly after incorporation of the POSS moiety, which presumably formed an inorganic protection layer on the nanocomposite's surface. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Plasma Polymerization of Zinc Acetyl Acetonate for the Development of a Polymer‐based Zinc Release System
Authors: Duque Luis , Förch Renate
Published: March 2011

Growing interest in novel materials for biomedical applications has promoted the investigation of composite materials that involve metal ions or metallic nanoparticles embedded in an organic polymeric matrix. The aim of the current work was the development of metal containing thin organic films, the material characterization and a study of the metal release properties when immersed in aqueous solution. Using a multitude of standard surface analytical tools and sophisticated optical techniques it could be shown that the plasma deposits of zinc acetylacetonate consist of nanometre‐sized ZnO particle inclusions in a highly oxygenated organic matrix. Infrared reflection absorption spectroscopy suggests some retention of the complex structure of the monomer. This is lost upon immersion in water as the zinc is released into the surrounding solution. The amount of zinc in the film and its release was shown to be dependent on the plasma conditions used and the thickness of the film. The ultimate goal of this study is the development of a zinc metal release system showing antimicrobial properties.

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The structural and optical properties of Volmer–Weber‐type ZnO nanorods
Authors: Park Se‐Jeong , He Weizhen , Qiu Jijun , Kim Jin Woo , Lee Ik Jae , Kim Beomkeun , Kim Hyung‐Kook , Hwang Yoon‐Hwae
Published: March 2011

Volmer–Weber‐type ZnO nanorods (VW ZnO NRs) were fabricated by using a hybrid method combined with RF sputtering and hydrothermal methods. The structural and optical properties of VW ZnO NRs were investigated by using synchrotron X‐ray diffraction (XRD), micro‐Raman spectroscopy, photoluminescence (PL) spectroscopy and X‐ray photoelectron spectroscopy (XPS). It was found that VW ZnO NRs showed wurtzite structure and were vertically standing on a substrate with a compressive stress from the substrate that can be reduced by annealing. In the micro‐Raman study, a forbidden E1(LO) mode in a bulk ZnO was observed in VW ZnO NRs due to the many edges in NR structures. It was also confirmed that VW ZnO NRs have a wurtzite structure by observing E2 low and E2 high peaks. In the PL spectra, VW ZnO NRs showed a broad emission in the visible range, especially yellow emission, with a weak UV emission. The UV emission was monotonously enhanced on increasing the annealing temperature. The yellow emission was enhanced in the annealed sample at 200 °C due to an evaporation of hydroxyl groups (OH−) on the surface of VW ZnO NRs.
Tensor and spatially resolved analysis of microscopic stress fields in polycrystalline alumina by polarized Raman spectroscopy
Authors: Zhu Wenliang , Pezzotti Giuseppe
Published: March 2011

A spectroscopic method is shown to resolve the full set of components of the residual stress tensor, as it locally develops on the microstructural scale in polycrystalline alumina. A polarized/confocal Raman probe is employed. As a first step, the local crystallographic orientation of alumina grains is extracted from the angular dependence of the intensities of polarized Raman bands (i.e., upon in‐plane rotation experiments) and expressed in terms of three Euler angles. Then, the stress tensor components for an unknown multiaxial stress state, expressed in their most general form through the Euler transformation matrix, are retrieved from solving the system of linear equations linking them to the observed spectral shifts of different (polarized) Raman bands. In order to clarify the sub‐surface characteristics of the Raman probe and their effect of the assessment of the stress field stored among the alumina grains, both in‐depth (defocusing) and in‐plane (focal shift) analyses were first carried out to quantitatively determine the three‐dimensional response of the Raman probe. Then, a computer‐aided data restoration procedure was applied to the experimental data, which minimized the averaging effect of the laser probe and brought about the actual magnitude of the residual stress components. From the physics viewpoint, the most relevant feature of the newly proposed stress analysis is that stress tensor components could be individually determined without a direct knowledge of the secular equation pertaining the corundum crystal.