bluuebunny/crossref_metadata_2025_split huggingface dataset:
Congenital thrombotic thrombocytopenic purpura (cTTP) with two novel mutations
Authors: Prestidge Timothy D. , Rurali Erica , Wadsworth Louis , Wu John K. , Moore Jane C. , Bresin Elena 
Published: April 2012

AbstractCongenital thrombotic thrombocytopenic purpura (cTTP) is a rare disorder of childhood that has clinical and laboratory similarities to other, more common conditions. Prompt recognition is required as delays in therapy are associated with significant morbidity and failure to treat may lead to death. While the principles of treatment have not changed, enormous progress in the genetic and molecular understanding has taken place. Emerging treatment options may offer some hope of improved quality of life in future. We describe a Chinese patient with cTTP which resulted from two previously undescribed mutations in the ADAMTS13 gene. Pediatr Blood Cancer 2012; 59: 1296–1298. © 2012 Wiley Periodicals, Inc.
Silver/polystyrene nanocomposites: Optical and thermal properties
Authors: Vodnik Vesna , Božanić Dušan K. , Džunuzović Jasna V. , Vukoje Ivana , Nedeljković Jovan 
Published: April 2012

AbstractNanocomposites consisted of different quantities of silver (Ag) nanoparticles incorporated in a polystyrene (PS) matrix have been prepared by solution mixing method. Transmission electron microscopy was applied to determine the size distribution of the Ag nanoparticles, while the morphology of fractured surfaces of pure PS and Ag/PS nanocomposites was examined by scanning electron microscopy. Absorption spectra of nanocomposites were compared with theoretically calculated spectra based on the Maxwell‐Garnett effective medium theory. The influence of Ag content on thermal properties of Ag/PS nanocomposites was investigated by thermogravimetric analysis and differential scanning calorimetry. Thermal and thermo‐oxidative stability of the host polymer were improved by introduction of silver nanoparticles. The glass transition temperature of the prepared Ag/PS nanocomposites was lower in comparison with the neat PS and decreased with the increase of the Ag content due to the very weak interfacial interaction between Ag nanoparticles and polymer matrix. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Effect of organoclays on the thermal, mechanical, and oxygen barrier properties of poly(methylmethacrylate‐co‐acrylonitrile)/clay nanocomposites
Authors: Patra Subrata K. , Swain Sarat K. 
Published: April 2012

AbstractThe nanostructured hybrid materials of poly(methylmethacrylate‐co‐acrylonitrile) copolymer were synthesized with incorporation of two organically modified clays, Cloisite® 30B and 93A by in situ intercalative emulsifier‐free emulsion polymerization method. The synthesized products were characterized by Fourier transform infrared spectroscopy to get evidence of copolymerization and formation of copolymer‐clay nanocomposite. X‐ray diffraction study and transmission electron microscopy analysis revealed that the clays were successfully intercalated and exfoliated into the copolymer matrix. Thermal properties of the nanocomposites were studied as a function of clay content of different clay types by thermogravimetric analysis. The results showed significant effect of both the clays in enhancing thermal resistance of the materials. Mechanical properties of the composites were also found to be improved at optimum clay loading. Oxygen barrier property of these materials was measured and it was found that the oxygen permeability was reduced almost by half due to incorporation of clays at 3% loading. Further, it was observed that Cloisite® 93A was more effective for improvement in properties when compared with Cloisite® 30B in the hybrid materials. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Aroma Evaluation of Gamazumi (Viburnum dilatatum) by Aroma Extract Dilution Analysis and Odour Activity Value
Authors: Miyazawa Mitsuo , Hashidume Shunsuke , Takahashi Toshiyuki , Kikuchi Tohru 
Published: April 2012

IntroductionViburnum dilatatum (gamazumi) is widely distributed in Japan and China. Recently, juice from V. dilatatum fruits has been manufactured in Japan. Concerning the aroma of V. dilatatum, phenethyl alcohol, 3Z‐hexenol and l‐linalool have been identified in the essential oil from the flowers of V. dilatatum, however, there are no detailed reports on the aroma of V. dilatatum elucidated using sensory evaluation.ObjectiveTo clarify odourants contributing to the characteristic aroma, the aroma extract dilution analysis (AEDA) method was performed through gas chromatography olfactometry (GC‐O) analysis.MethodologyThe aroma‐active compounds were identified by GC‐O and AEDA, and in order to determine the relative contribution of each compound to the aroma of V. dilatatum, odour activity value (OAV) has been used.ResultsThe hydrodistillation of the leaf and branch of V. dilatatum afforded pale yellowish oils, with yields of 0.008 and 0.015% (w/w). The main components of the leaf oil were 3Z‐hexenal (12.7%) and linalool (10.8%). In branch oil, palmitic acid (18.3%) and linoleic acid (8.2%) were identified. With regard to aroma components, 24 and 14 compounds were identified in the leaf and branch oils respectively, by GC‐O analysis.ConclusionOn the basis of AEDA, OAVs and sensory evaluations, nonanal is estimated as the main aroma compound of leaf and branch oil, as the other aroma compounds, C6 compounds and 2‐pentyl furan make green odour; linalool, eugenol and β‐ionone play important role in the sweet odour of leaf oil. In branch oil, cis‐furanlinalool oxide and eugenol make sweet odour, and β‐eudesmol contributes to woody odour. Copyright © 2011 John Wiley & Sons, Ltd.
Quantitation of α‐Galactosides in Rehmannia glutinosa by Hydrophilic Interaction Chromatography–Evaporative Light Scattering Detector
Authors: Kim Tae Bum , Kim Seung Hyun , Sung Sang Hyun 
Published: April 2012

ABSTRACTIntroductionThe use of raffinose family oligosaccharides (RFOs) to control several diseases and stimulate immune systems has been studied. Rehmannia glutinosa is reported to contain RFOs; however, there are no reports on their content level in R. glutinosa. Furthermore, it is difficult to analyse RFOs using common reverse‐phase chromatographic techniques due to their high polarity.ObjectiveTo develop a rapid and reliable chromatographic method for the simultaneous quantitation of multiple RFOs in R. glutinosa.MethodologyChromatographic separation was performed by using hydrophilic interaction liquid chromatography coupled with an evaporative light scattering detector. For efficient ultrasound‐assisted extraction of oligosaccharides, a central composite design was used.ResultsResponse surface analysis estimated the highest‐obtained yields of raffinose, stachyose and verbascose to be 58.31, 408.75 and 26.59 mg, respectively, from 1 g of R. glutinosa, while under optimal conditions, experimental yields per gram were 56.79, 391.42 and 27.69 mg, respectively.ConclusionA rapid and reliable chromatographic method to simultaneously quantitate multiple RFOs in R. glutinosa was developed. Three RFOs in R. glutinosa were separated within 10 min using isocratic conditions. Quantitative analysis of RFOs showed that R. glutinosa may be a rich source of α‐galacto‐oligosaccharides, especially stachyose. Copyright © 2012 John Wiley & Sons, Ltd.
Interdiffusion of thermoplastics and epoxy resin precursors: investigations using experimental and molecular dynamics methods
Authors: Dumont David , Seveno David , De Coninck Joël , Bailly Christian , Devaux Jacques , Daoust Daniel 
Published: April 2012

AbstractToughening of epoxy thermosets with thermoplastics is an important avenue towards improved properties of high‐performance systems. The main focus of the work reported was to study the complex issue of interdiffusion between thermoplastics and epoxy resin precursors, using a combination of experimental and numerical simulation methods, in order to understand the key parameters driving the process. Diameter changes of thermoplastic filaments in contact with epoxide and diamine precursors have been followed and an original approach using carbon nanotubes as tracers of the filament swelling front has been developed. This method shows that the improved mobility of low‐molecular‐weight resin monomers as well as the greater mobility of phenoxy of lower glass transition temperature as compared to poly(ether sulfone) control dissolution by favouring the penetration of precursors into the thermoplastic and lead to both swelling of the outer part of the filaments and reduction of the inner unaffected core. Simulation by molecular dynamics supports the idea that diffusion of polymer macromolecules remains limited compared to the dominant effect of precursor diffusion. Indeed, low diffusion coefficients have been predicted for thermoplastic oligomers compared to resin monomers. For the latter, the calculated values correlate well with the experimental data measured during interdiffusion. Copyright © 2012 Society of Chemical Industry
Microwave‐assisted synthesis and bulk polymerization of 3‐aminophthalic anhydride as an AB‐type monomer for the formation of linear and cyclic polyimides
Authors: Theis Julia , Ritter Helmut 
Published: April 2012

Abstract3‐Aminophthalic anhydride was synthesized in high purity by heterogeneous catalytic transfer hydrogenation of 3‐nitrophthalic acid. The reduction was carried out in a one‐pot reaction under microwave conditions, using 4‐methyl‐1‐cyclohexene as a source of hydrogen, in short reaction times. By microwave‐assisted polymerization of the resulting AB‐type amino anhydride monomer in bulk, linear and cyclic polymers consisting of amic acid and imide units were formed. Copyright © 2012 Society of Chemical Industry
Effect of voltage sweep direction on the performance evaluation of P3HT : PCBM solar cells
Authors: Kumar Pankaj , Sharma Abhishek , Singh Dwijendra Pratap 
Published: April 2012

ABSTRACTInvestigations on the effect of direction of voltage sweeps, on the current density–voltage (J–V) characteristics in polymer bulk‐heterojunction solar cells, based on the blend of poly(3‐hexylthiophene) (P3HT) and phenyl [6,6] C61 butyric acid methyl ester (PCBM), are reported with time. On the freshly prepared device, the direction of the voltage sweep did not have any effect; however, as the device started degrading, the change in direction of the voltage sweep resulted into different characteristics. Analysis beyond complete degradation, when all the photovoltaic parameters reduced to zero, revealed some interesting results. The J–V characteristics, measured with voltage sweep from −ve to +ve voltage, both in the dark and under illumination, were observed to pass through the second quadrant. On the other hand, with the change in the direction of voltage sweep, viz. from +ve to −ve voltage, the characteristics both in the dark and under illumination passed through the fourth quadrant. These results have been explained on the basis of polarization of the degraded active layer due to applied external voltage. This is an important effect and is observed to depend on the applied voltages during performance evaluation and becomes more prominent with time. This effect puts a question mark on the correctness of the method for calculation of the parameters of a degraded device. Studies on degradation of P3HT : PCBM solar cells showed that both the short circuit current density (Jsc) and the power conversion efficiency (η) decay exponentially, whereas the open circuit voltage (Voc) decays almost linearly with time. Copyright © 2012 John Wiley & Sons, Ltd.
Diffusion‐free high efficiency silicon solar cells
Authors: Prajapati Victor , Janssens Tom , John Joachim , Poortmans Jef , Mertens Robert 
Published: April 2012

ABSTRACTTraditional POCl3 diffusion is performed in large diffusion furnaces heated to ~850 C and takes an hour long. This may be replaced by an implant and subsequent 90‐s rapid thermal annealing step (in a firing furnace) for the fabrication of p‐type passivated emitter rear contacted silicon solar cells. Implantation has long been deemed a technology too expensive for fabrication of silicon solar cells, but if coupled with innovative process flows as that which is mentioned in this paper, implantation has a fighting chance. An SiOx/SiNy rear side passivated p‐type wafer is implanted at the front with phosphorus. The implantation creates an inactive amorphous layer and a region of silicon full of interstitials and vacancies. The front side is then passivated using a plasma‐enhanced chemical vapor deposited SiNxHy. The wafer is placed in a firing furnace to achieve dopant activation. The hydrogen‐rich silicon nitride releases hydrogen that is diffused into the Si, the defect rich amorphous front side is immediately passivated by the readily available hydrogen; all the while, the amorphous silicon recrystallizes and dopants become electrically active. It is shown in this paper that the combination of this particular process flow leads to an efficient Si solar cell. Cell results on 160‐µm thick, 148.25‐cm2 Cz Si wafers with the use of the proposed traditional diffusion‐free process flow are up to 18.8% with a Voc of 638 mV, Jsc of 38.5 mA/cm2, and a fill factor of 76.6%. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis and properties of star polymers with a C5‐symmetric bowl‐shaped aromatic core
Authors: Stuparu Mihaiela C. 
Published: April 2012

AbstractWe report the synthesis and properties of star polymers with a C5‐symmetric aromatic core. For this, corannulene‐based penta‐substituted polymerization initiators were synthesized. These initiators were then used to polymerize cyclic ester and styrenic monomers via ring opening polymerization and free radical polymerization methods, respectively. Preliminary results suggest that these novel polymers can interact with fullerene, C60, and the degree of interaction can be tuned by the chemical nature of the solvent. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Hyperbranched photo responsive and liquid crystalline azo‐siloxane polymers synthesized by click chemistry
Authors: Pandey Someshwarnath , Mishra Sarada P. , Kolli Balakrishna , Kanai Tapan , Samui Asit B. 
Published: April 2012

AbstractThree new types of hyperbranched photoactive liquid crystalline siloxane polymers containing azo moieties were synthesized using click chemistry methodology. The polymers were soluble in most of the polar solvents like chloroform, tetrahydrofuran, dimethylformamide, dimethyl sulphoxide and dichloromethane. The molecular weights of the polymers were in the range of 9000–12,000 g mol−1. The trans‐cis photoisomerization of the polymer were studied both under UV radiation and dark. The isomerization rate constants were found to be in the range of 0.7–1.4 × 10−2 sec−1 and 7.0 × −2.5 × 10−5 sec−1. The thermotropic behavior of the polymers was studied by using polarizing optical microscopy and differential scanning calorimetry, respectively. The polymers P1 and P2 showed liquid crystalline texture characteristic of nematic phase. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Biodegradable stereocomplex materials of polylactide‐grafted dextran exhibiting soft and tough properties in dry and wet states
Authors: Nagahama Koji , Shimizu Keiko , Ichimura Shunsuke , Takahashi Akihiro , Ouchi Tatsuro , Ohya Yuichi 
Published: April 2012

AbstractWater‐swellable biodegradable materials exhibiting mechanically tenacious and tough characters in the wet state were prepared by a simple blend of two enantiomeric polylactide‐grafted dextran copolymers (Dex‐g‐PLLA and Dex‐g‐PDLA). DSC and WAXD analyses demonstrated the formation of SC crystals in the copolymer blend films. SC blend films showed lamellar‐type microphase‐separated structures. When swollen with water, these blend films showed the same level of tensile strengths and Young's modulus as the films in the dry state. SC blend films degraded gradually over a month under physiological conditions with a degradation rate faster than the corresponding Dex‐g‐PLLA films. The SC‐forming enantiomeric mixture of polylactide‐grafted polysaccharides should be a good candidate for an implantable biocompatible material exhibiting favorable mechanical properties and degradation behavior. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Preparation of poly(acrylic acid)‐b‐polystyrene by two‐step atom transfer radical polymerization in supercritical carbon dioxide
Authors: Minami Hideto , Tanaka Atsushi , Kagawa Yasuyuki , Okubo Masayoshi 
Published: April 2012

AbstractIt is known that it is difficult to polymerize carboxylic acid‐based monomer by atom transfer radical polymerization (ATRP) in polar solvents due to the protonation of ligand caused by acidic dissociation of the monomer. In this study, precipitation reverse ATRP of acrylic acid (AA) was carried out in supercritical carbon dioxide (scCO2), which is a nonpolar solvent to dissolve transition metal complexes, at 30 MPa and 45 °C. The polymerization proceeded smoothly and the conversion reached 86% for 3 h. After vending of scCO2, a dry poly(acrylic acid) (PAA) powder was obtained. Weight‐average molecular weight and polydispersity of the methylated PAA, which were measured by gel‐permeation chromatography after methyl esterification, were 3.5 × 104 and 2.07, respectively, indicating that the precipitation reverse ATRP proceeded with a bad control manner. However, chain extension of the methylated PAA with styrene was possible by ATRP in a bulk system. Moreover, PAA‐b‐polystyrene was successfully prepared in scCO2 directly by two‐step ATRP, although its molecular weight distribution was broad. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Associations of obesity and asthma with functional exercise capacity in urban minority adolescents
Authors: Rastogi Deepa , Khan Unab I. , Isasi Carmen R. , Coupey Susan M. 
Published: April 2012

AbstractPurposeTo examine the independent association of asthma and obesity and of their co‐existence with functional exercise capacity among urban adolescents.MethodsOne hundred eighteen Hispanic‐ and African‐American adolescents including 33 obese asthmatics, 18 normal‐weight asthmatics, 38 obese non‐asthmatics, and 29 normal‐weight non‐asthmatics underwent anthropometric measures, 6‐minute walk test (6MWT) as measure of functional exercise capacity and spirometry as measure of pulmonary function. The 6‐minute walk distance (6MWD) was compared between the four study groups. The association of 6MWD with measures of lower airway obstruction, and measures of adiposity was assessed.ResultsThe 6MWD was lower among the obese groups with the least distance covered by the obese asthmatic group (P = 0.02). In the obese asthmatic group, there was a negative correlation between 6MWD and body mass index (BMI) (r = −0.35, P = 0.03), but no association was noted with percent‐predicted forced expiratory volume in the 1st second (FEV1; r = 0.07, P = 0.70). Conversely, the 6MWD correlated with FEV1 among normal‐weight asthmatics (r = 0.45, P = 0.04) and normal‐weight non‐asthmatics (r = 0.4, P = 0.03), but was not associated with BMI in either of the two groups. After adjusting for age, height, gender, and ethnicity, BMI was noted to be a significant predictor (β −2.76, 95% CI −4.77 to −0.76, P < 0.01) of the 6MWD among the obese while percent predicted FEV1 (β 1.87, 95% CI 0.28–3.45, P = 0.02) was a significant predictor among the normal‐weight participants.ConclusionsOur findings suggest that among urban minority obese asthmatic adolescents, functional exercise capacity was associated with obesity, rather than pulmonary function. Pediatr Pulmonol. 2012. 47:1061–1069. © 2012 Wiley Periodicals, Inc.
Developmental and genetic aspects of congenital diaphragmatic hernia
Authors: Veenma D.C.M. , de Klein A. , Tibboel D. 
Published: April 2012

AbstractCongenital diaphragmatic hernia (CDH) is a frequent occurring cause of neonatal respiratory distress and occurs 1 in every 3,000 liveborns. Ventilatory support and pharmaceutical treatment of the co‐occurring lung hypoplasia and pulmonary hypertension are insufficient in, respectively, 20% of isolated cases and 60% of complex ones leading to early perinatal death. The exact cause of CDH remains to be identified in the majority of human CDH patients and prognostic factors predicting treatment refraction are largely unknown. Their identification is hampered by the multifactorial and heterogenic nature of this congenital anomaly. However, application of high‐resolution molecular cytogenetic techniques to patients' DNA now enables detection of chromosomal aberrations in 30% of the patients. Furthermore, recent insights in rodent embryogenesis pointed to a specific disruption of the early mesenchymal structures in the primordial diaphragm of CDH‐induced offspring. Together, these data allowed for the introduction of new hypotheses on CDH pathogenesis, although many issues remain to be resolved. In this review, we have combined these new insights and remaining questions on diaphragm pathogenesis with a concise overview of the clinical, embryological, and genetic data available. Pediatr Pulmonol. 2012; 47:534–545. © 2012 Wiley Periodicals, Inc.
The fraction of NO in exhaled air and estimates of alveolar NO in adolescents with asthma: Methodological aspects
Authors: Heijkenskjöld‐Rentzhog Charlotte , Alving Kjell , Kalm‐Stephens Pia , Lundberg Jon O , Nordvall Lennart , Malinovschi Andrei 
Published: April 2012

AbstractRationaleThis study investigated the oral contribution to exhaled NO in young people with asthma and its potential effects on estimated alveolar NO (CalvNO), a proposed marker of inflammation in peripheral airways. Secondary aims were to investigate the effects of various exhalation flow‐rates and the feasibility of different proposed adjustments of (CalvNO) for trumpet model and axial diffusion (TMAD).MethodsExhaled NO at flow rates of 50–300 ml/sec, and salivary nitrite was measured before and after antibacterial mouthwash in 29 healthy young people (10–20 years) and 29 with asthma (10–19 years). CalvNO was calculated using the slope–intercept model with and without TMAD adjustment.ResultsExhaled NO at 50 ml/sec decreased significantly after mouthwash, to a similar degree in asthmatic and healthy subjects (8.8% vs. 9.8%, P = 0.49). The two groups had similar salivary nitrite levels (56.4 vs. 78.4 µM, P = 0.25). CalvNO was not significantly decreased by mouthwash. CalvNO levels were similar when flow‐rates between 50–200 or 100–300 ml/sec were used (P = 0.34 in asthmatics and P = 0.90 in healthy subjects). A positive association was found between bronchial and alveolar NO in asthmatic subjects and this disappeared after the TMAD‐adjustment. Negative TMAD‐adjusted CalvNO values were found in a minority of the subjects.ConclusionsYoung people with and without asthma have similar salivary nitrite levels and oral contributions to exhaled NO and therefore no antibacterial mouthwash is necessary in routine use. TMAD corrections of alveolar NO could be successfully applied in young people with asthma and yielded negative results only in a minority of subjects. Pediatr Pulmonol. 2012. 47:941–949. © 2012 Wiley Periodicals, Inc.