bluuebunny/crossref_metadata_2025_split huggingface dataset:
Préparation de Polystyrènes à Ramification Contrôlée
Authors: Rempp Paul , Decker‐Freyss Danielle 
Published: September 2014

AbstractPreparation of branched “comblike” polystyrene has been performed by two different methods derived from the anionic grafting techniques. Grafting by carbanionic initiation can be utilized: as its basis we have used statistical copolymers of styrene and p‐bromostyrene. Partial metallation of the p‐bromostyrene units is performed by naphthalene—lithium and the metallated sites are used as initiators for the polymerization of styrene. Thus, branched polystyrene samples were obtained. Grafting by carbanionic deactivation has also been applied. The “backbone” chain is a statistical copolymer of styrene and methylmethacrylate. The ester functions are used as electrophilic deactivators for “living” polystyrene chains. Easily characterizable samples of low polydispersity have been obtained, fractionated, studied by light scattering, and characterized as “comb” polymers. The advantages and disadvantages of both methods are discussed.
Polycycloaddition of terephthalonitrile oxide
Authors: Overberger C. G. , Fujimoto Sumio 
Published: September 2014

AbstractTerephthalonitrile oxide (TNO) of various crystalline states was prepared and its structure was studied by infrared spectroscopy, x‐ray diffraction, and hydrolysis. Biscycloadditions of unsaturated compounds such as ethynylbenzene, styrene, benzonitrile, and cyclopentadiene were found to yield 1,4‐bis(5‐phenyl‐3‐isoxazolyl)‐benzene, 1,4‐bis‐(5‐phenyl‐3‐isoxazolinyl)‐benzene, 1,4‐bis‐(5‐phenyl‐1,2,4‐oxadiazolyl)‐benzene, and 1,4‐bis‐(4,5‐cyclopent‐3′‐ene‐3‐isoxazolinyl)‐benzene, respectively. Solution polymerization of TNO gave a polyfuroxan, which had an alternating structure of p‐phenylene and furoxan rings. Polymerization of TNO in the solid state also gave a polymer, whose structure was postulated as a polyoxazoxime. Copolymerizations of TNO with bifunctional unsaturated compounds such as 1,4‐diethynylbenzene, terephthalonitrile, cyclopentadiene, quinone, and allene yielded 1:1 alternating copolymers containing p‐phenylene units and corresponding ring structures.
Beziehungen zwischen den dynamischen Eigenschaften und der Schlagzähigkeit der Mischungen des Polyvinylchlorids mit Kautschuk
Authors: Zelinger Jiří 
Published: September 2014

AbstractMeasurements of dynamic properties of a series of polyvinylchloride‐rubber blends at temperatures of −60 to +100°C and frequencies of 0.3–3.0 Hz have been carried out by means of the free vibration method. The dynamic data have been compared to the results of impact resistance Charpy‐experiments. The linear correlation obtained between the dynamic shear modulus at −10°C (G′−10) and the impact resistance at 20°C indicated that the value G′−10 has to be decreased compared to that of unmodified PVC to increase the resistance of compatible as well as incompatible PVC‐rubber blends. The impact resistance increases with higher decrease of G′−10. The correlation given and the breaking characteristics of the samples investigated show that, ductile fracture, relieving the deformational stress mainly by developing cracks, occurs in blends with G′−10 in the range of 12.0–7.5 × 108 N/m2. This is valid for compatible as well as incompatible PVC rubber blends.
Über einige elektrische Eigenschaften von Metall—Tetracyanoäthyleniden und ihren Polymeren
Authors: Storbeck I. 
Published: September 2014

AbstractA copper tetracyanoethylene polymer has been prepared and its thermal stability investigated. Direct current resistivity, thermo e.m.f., and thermal conductivity of the initial product and of the annealing products have been determined as a function of temperature. The relative dielectric constant has been measured in the frequency range of 50 cps to 500 kc./sec. The electric measurements and infrared spectra allowed to conclude that destruction of the polymers by copper degradation occurs at 250–300°C.
Über Bildung und Zerfall von Peroxiden in strahlenoxydiertem Polyvinylchlorid (PVC)
Authors: Zeppenfeld G. , Bartl A. 
Published: September 2014

AbstractWe succeeded in determining quantitatively hydroperoxides and peroxiradicals in radiation‐oxidized polyvinyl chloride (PVC) by combining the chemical method with electron paramagnetic resonance. PVC oxidized by radiation contains two different kinds of peroxiradicals and one of hydroperoxide. 60% of peroxiradicals decay at 20°C in atmospheric oxygen at a half time T½ ∼ 3 hr. 40% of peroxiradicals are relatively stable at room temperature. They decay at 56°C. in vacuum with T½ ∼ 40 hr. The hydroperoxide R″COOH decays at 50°C. in vacuum with T½ = 650 hr. The activation energy of decay is E = 35 kcal./mole in a temperature range of 50 to 75°C.
Contribution à l'Étude de la Polymérisation Radiochimique de l'Isopréne en Phase Solide
Authors: Hinschberger André , Marchal Jean , Vacherot Monique , Dworkin Ary , Roncin Jean 
Published: September 2014

AbstractThe study by calorimetry of the γ irradiation induced polymerization of isoprene in the solid state showed that the reaction took place through irradiation. No post‐effect was observed while heating the polymer from the irradiation temperature to the melting point. Gas chromatography analysis showed that, with respect to the polymer, the proportion of minor products resulting from irradiation was small. After UV irradiation of solid isoprene we found the same radical, vinyl 2‐allyl, as after γ irradiation.
Détermination de la Polydispersité en Masse Moléculaire et en Composition Chimique d'un Copolymère Greffé Poly(isobutylene) Poly(Styrène) Préparé Par Voie Radiochimique
Authors: Danon Jeanne , Jozefowicz Jacqueline 
Published: September 2014

AbstractA graft copolymer of polyisobutylene–polystyrene prepared radiochemically and possessing both a molecular weight polydispersity and chemical heterogeneity has been fractionated by elution on a column. The system solvent–precipitant has been chosen in order to produce a fractionation essentially on the basis of the molecular weight. Some fractions have been examined by light diffusion in order to determine their polydispersities of molecular weight and of chemical composition. This study permits the conclusion that the fractionation was indeed obtained on the basis of molecular weight differences.
New monomers involving nitrogen and sulfur and their polymers
Authors: Sidelkovskaya F. P. , Avetisyan A. A. , Zelenskaya M. G. 
Published: September 2014

AbstractVinyl and allyl derivatives of cyclic thioamides containing an unsaturated radical at nitrogen or sulfur have been synthesized and their homopolymers and copolymers prepared. The synthesized polymers were converted to other polymers by suitable reactions.
Cyclopolymerization of unconjugated dienes
Authors: Trossarelli L. , Guaita M. , Priola A. 
Published: September 2014

AbstractThe experimental results of an investigation on the products obtained from the free radical polymerization of some unsymmetrical unconjugated dienes, such as N‐allyl‐methacrylamide, N‐allylacrylamide, allyl methacrylate, and allyl acrylate, are presented and discussed, reference being made to some general relationships between monomer concentration and eyclopolymer composition (from the point of view of the possible structural units). Data on the relative reactivities of the two double bonds of these monomers toward the attacking radicals are obtained which allow us to get some interesting informations about the intramolecular and intermolecular steps of the cyclopolymerization process.
Deformation of compensated piled raft foundations with deep embedment in super‐tall buildings of Shanghai
Authors: Yongjing Tang , Xihong Zhao 
Published: September 2014

SummaryThis paper presents a synergetic approach based on a statistical‐empirical method, conservation of energy method and superstructure‐foundation interaction theory, and this paper aims to estimate the deformation level of a compensated piled raft foundation. The advantages and main characteristics of such a compensated piled raft foundation are described, and a history of the heave, recompression deformation and final settlement data measurements is provided. Case studies of four super‐tall buildings, the 88‐story Jinmao Building, 66‐story Henglong Plaza, 101‐story Shanghai World Financial Center and 121‐story Shanghai Center Tower in Shanghai, all of which are engineering projects that the second author participated in, are provided to illustrate the effectiveness of different calculations for heave, recompression deformation and final settlement. This study demonstrates that the deformation process can be reasonably projected for a piled raft foundation with deep embedment in Shanghai using superstructure‐foundation interaction methods, statistical‐empirical formulas and a method based on the conservation of energy. The coefficients in the statistical‐empirical method are also further optimized. This deformation estimation considering compensation for deep embedment unloading is reasonable and can be used to avoid excessively conservative designs, and the synergetic approach is applicable to any compensated piled raft foundation with deep embedment in Shanghai. Copyright © 2014 John Wiley & Sons, Ltd.
A taxonomic and phylogenetic revision of Penicillium section Aspergilloides
Authors: Houbraken J. , Visagie C.M. , Meijer M. , Frisvad J.C. , Busby P.E. , Pitt J.I. , Seifert K.A. , Louis-Seize G. , Demirel R. , Yilmaz N. , Jacobs K. , Christensen M. , Samson R.A. 
Published: September 2014

Species belonging to Penicillium section Aspergilloides have a world-wide distribution with P. glabrum, P. spinulosum and P. thomii the most well-known species of this section. These species occur commonly and can be isolated from many
substrates including soil, food, bark and indoor environments. The taxonomy of these species has been investigated several times using various techniques, but species delimitation remains difficult. In the present study, 349 strains belonging to section Aspergilloides were subjected
to multilocus molecular phylogenetic analyses using partial β-tubulin (BenA), calmodulin (CaM) and RNA polymerase II second largest subunit (RPB2) sequences. Section Aspergilloides is subdivided into 12 clades and 51 species. Twenty-five species are described
here as new and P. yezoense, a species originally described without a Latin diagnosis, is validated. Species belonging to section Aspergilloides are phenotypically similar and most have monoverticillate conidiophores and grow moderately or quickly on agar media. The most
important characters to distinguish these species were colony sizes on agar media, growth at 30 °C, ornamentation and shape of conidia, sclerotium production and stipe roughness.
Reconstructing the Timing of Flash Floods Using10Be Surface Exposure Dating at Leidy Creek Alluvial Fan and Valley, White Mountains, California–Nevada, USA
Authors: Fuchs Markus , Reverman Rebecca , Owen Lewis A. , Frankel Kurt L. 
Published: September 2014

AbstractLarge alluvial fans characterize the piedmonts of the White Mountains, California–Nevada, USA, with large boulders strewn across their surfaces. The boulders are interpreted as flash floods deposits with an unclear trigger for the transport process. Several triggers are possible, including glacial lake outburst floods (GLOFs), thunderstorms or rainfall on snow cover. From a paleoenvironmental perspective, the origin of the flash floods is of fundamental importance. The alluvial fans that flank the White Mountains at Leidy Creek display particularly impressive examples of these deposits. The boulder deposits and the source catchment at Leidy Creek were examined using10Be terrestrial cosmogenic nuclide (TCN) surface exposure dating to help elucidate their age and origin. All boulders dated on the alluvial fans date to the Holocene. This is in accordance with the geomorphic analyses of the Leidy Creek catchment and its terraces and sediment ridges, which were also dated to the Holocene using optically stimulated luminescence (OSL) and10Be surface exposure. The results suggest that the boulders on the alluvial fan were deposited by flash floods during thunderstorm events affecting the catchment of the Leidy Creek valley. Paleomonsoonal-induced mid-Holocene flash floods are the most plausible explanation for the discharges needed for these boulder aggradations, but a regional dataset is needed to confirm this explanation.
Fluid migration between confined aquifers
Authors: Pegler Samuel S. , Huppert Herbert E. , Neufeld Jerome A. 
Published: September 2014

AbstractWe study the two-dimensional flow and leakage of buoyant fluid injected at a constant volumetric rate into a fluid-saturated porous medium confined vertically by horizontal boundaries. The upper boundary contains a localized vertical fracture that allows fluid to leak into an open or partially confined porous layer above. The rate of leakage is modelled as proportional to the combined action of the gravitational hydrostatic head of the current below the fracture and the background pressure introduced by the injection. After the injected current reaches the fracture, leakage is initially controlled kinematically by the rate at which injected fluid flows towards the fracture. Once the rate at which buoyant fluid flows towards the fracture exceeds a critical value, the current overshoots the fracture and leakage switches to being controlled dynamically by the pressure drop across the fracture. Two long-term regimes of flow can emerge. In one, the current approaches a steady height above the lower boundary and essentially all fluid injected into the medium leaks at long times. In the other, the current accumulates to fill the entire depth of the medium below the fracture. Only a fraction of the injected fluid then leaks at long times, implying significantly greater long-term storage than has been proposed from studies of leakage from unconfined media. An understanding of the flow regimes is obtained using numerical solutions and analysis of long-term similarity solutions. The implications of our results to the geological storage of carbon dioxide is discussed.
Mach number effects on the global mixing modes induced by ramp injectors in supersonic flows
Authors: Massa Luca 
Published: September 2014

AbstractModern injectors for supersonic combustors (hypermixers) augment the fuel–air mixing rate by energizing the perturbation in the mixing layer. From an instability point of view, the increased perturbation growth is linked to the increased complexity of the equilibrium base flow when compared to the axisymmetric mixing layer. Common added features are streamwise vortex streaks, oblique recompression shocks and Prandtl–Meyer expansions. One of the main effects of such distortions of the mean flow is to transform the instability responsible for the creation of fine scales from a local amplified mode to a global self-sustained fluctuation. The focus of the present research is on the flow distortion induced by flushed ramps for free-stream Mach numbers in the range 2.5–3.5. The principal mean flow features are the recirculation region due to the recompression of the flow after the ramp, the shear layer over the recirculation region and the vortex streaks propagating from the ramp corners. A global three-dimensional stability analysis and three-dimensional direct numerical simulations of small perturbations of the mean flow are performed. The growth and energy distribution of the dominant and subdominant fluctuations supported by the three-dimensional steady laminar base flow are computed. The main results are the growth rates of the self-sustained varicose and sinuous modes and their correlation to the variation in the free-stream Mach number. The complex three-dimensional wavemaker is investigated by evaluating the three-dimensional eigenfunctions of the direct and adjoint modes, and the effects of the axial vorticity generated by the ramp corners are discussed.
Dietary patterns and cardiovascular risk factors in adolescents and young adults: the Northern Ireland Young Hearts Project
Authors: McCourt Hannah J. , Draffin Claire R. , Woodside Jayne V. , Cardwell Chris R. , Young Ian S. , Hunter Steven J. , Murray Liam J. , Boreham Colin A. , Gallagher Alison M. , Neville Charlotte E. , McKinley Michelle C. 
Published: September 2014

Dietary pattern (DP) analysis allows examination of the combined effects of nutrients and foods on the markers of CVD. Very few studies have examined these relationships during adolescence or young adulthood. Traditional CVD risk biomarkers were analysed in 12–15-year-olds (n487; Young Hearts (YH)1) and again in the same individuals at 20–25 years of age (n487; YH3). Based on 7 d diet histories, in the present study, DP analysis was performed usinga posterioriprincipal component analysis for the YH3 cohort and thea prioriMediterranean Diet Score (MDS) was calculated for both YH1 and YH3 cohorts. In thea posterioriDP analysis, YH3 participants adhering most closely to the ‘healthy’ DP were found to have lower pulse wave velocity (PWV) and homocysteine concentrations, the ‘sweet tooth’ DP were found to have increased LDL concentrations, systolic blood pressure, and diastolic blood pressure and decreased HDL concentrations, the ‘drinker/social’ DP were found to have lower LDL and homocysteine concentrations, but exhibited a trend towards a higher TAG concentration, and finally the ‘Western’ DP were found to have elevated homocysteine and HDL concentrations. In thea prioridietary score analysis, YH3 participants adhering most closely to the Mediterranean diet were found to exhibit a trend towards a lower PWV. MDS did not track between YH1 and YH3, and nor was there a longitudinal relationship between the change in the MDS and the change in CVD risk biomarkers. In conclusion, cross-sectional analysis revealed that some associations between DP and CVD risk biomarkers were already evident in the young adult population, namely the association between the healthy DP (and the MDS) and PWV; however, no longitudinal associations were observed between these relatively short time periods.
Bayesian model selection for multiple QTLs mapping combining linkage disequilibrium and linkage
Authors: JIANG DAN , MA GUODA , YANG RUNQING , LI KESHEN , FANG MING 
Published: September 2014

SummaryLinkage disequilibrium (LD) mapping is able to localize quantitative trait loci (QTL) within a rather small region (e.g. 2 cM), which is much narrower than linkage analysis (LA, usually 20 cM). The multilocus LD method utilizes haplotype information around putative mutation and takes historical recombination events into account, and thus provides a powerful method for further fine mapping. However, sometimes there are more than one QTLs in the region being studied. In this study, the Bayesian model selection implemented via the Markov chain Monte Carlo (MCMC) method is developed for fine mapping of multiple QTLs using haplotype information in a small region. The method combines LD as well as linkage information. A series of simulation experiments were conducted to investigate the behavior of the method. The results showed that this new multiple QTLs method was more efficient in separating closely linked QTLs than single-marker association studies.
Mycological study on cholesteatoma keratin obtained during primary mastoid surgery
Authors: Effat K G , Madany N M 
Published: September 2014

AbstractObjective:Established middle-ear cleft cholesteatoma is associated with keratinous debris, which is likely to be an ideal medium for saprophytic fungal colonisation. This prospective case study aimed to explore the incidence and nature of fungal elements in cholesteatoma keratin samples obtained during primary mastoid surgery.Methods:All cases of middle-ear cleft cholesteatoma treated with primary mastoid surgery at the El-Sahel Teaching Hospital over a seven-month period were included. Keratinous debris obtained from the mastoid antrum was subjected to mycological analysis at the Department of Medical Microbiology and Immunology, Faculty of Medicine, Cairo University. A literature search was performed to determine the clinical and pathological relevance of fungal colonisation in cholesteatoma.Results:Eighteen patients underwent primary mastoid surgery for cholesteatoma (nineteen ears in total) in a seven-month period starting 30 March 2013. Patients included 13 males and 5 females, with an age range of 9 to 45 years (mean 23 years). Fungal cultures were obtained from 17 keratin samples (89 per cent). Of these, five fungal isolates belonged to the dermatophyte group (21 per cent).Conclusion:Fungal colonisation in middle-ear cleft cholesteatoma probably plays a significant role in disease progression. Moreover, saprophytic fungal colonisation in cholesteatoma keratin may be responsible for the fetor commonly associated with the ear discharge.
Daily variations inEscherichia coliO157 shedding patterns in a cohort of dairy heifers at pasture
Authors: WILLIAMS K. J. , WARD M. P. , DHUNGYEL O. P. 
Published: September 2014

SUMMARYEscherichia coliO157 is a human pathogen carried asymptomatically by cattle and shed in their faeces. Infection can occur from the consumption of contaminated beef or by direct contact. Large variations ofE. coliO157 shedding in cattle exist and vary in the number of cattle positive forE. coliO157 and the amount of bacteria (c.f.u./g faeces) shed by positive animals. To investigateE. coliO157 shedding and super-shedding (>104 c.f.u./g) we used daily sampling over two 8-day periods; in January 2013 (n = 12) and February 2013 (n = 21). Samples were tested by direct faecal culture for enumeration and by immunomagnetic separation to detect lower levels of shedding. We identified three patterns of shedding, similar to previously observed descriptions: intermittent, transient and consistent. The most commonly observed pattern was intermittent shedding and variation in the level of shedding could be large. This extreme variation is demonstrated by a heifer from whichE. coliO157 could be not detected one day, was super-sheddingE. coliO157 the next and was detected as shedding >100 c.f.u./g the following day. Recto-anal mucosal swab testing did not predict super-shedding in this cohort of heifers. The variable individual patterns of shedding suggest that a common mechanism of infection may not operate within such a herd when considering previously described patterns and the inferred mechanisms. The sporadic and intermittent nature of shedding is a challenge to identifying risk factors and potential intervention strategies.
Myocarditis in drug rash with eosinophilia and systemic symptoms
Authors: Ho Cynthia H. , Uzunyan Merujan Y. 
Published: September 2014

AbstractDrug rash with eosinophilia and systemic symptoms is a drug hypersensitivity reaction. Hepatitis and nephritis are the most common visceral manifestations. Myocarditis is important to recognise, given the high mortality rate. We describe a child with drug rash with eosinophilia and systemic symptoms and discuss the role of N-terminal pro-hormone of basic natriuretic peptide in early recognition of associated myocarditis.