bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving the water resistance of biodegradable collagen films
Authors: Sommer Isabell , Kunz Peter M. 
Published: February 2012

AbstractAlthough collagen‐based films have been successfully used for packaging in the meat industry, their potential as a replacement for synthetic packaging films in other industries has not yet been widely investigated. This may be due to the low water resistance of protein films. The objective of this study was to systematically improve water resistance in collagen‐based films and to investigate the influence of different crosslinking agents and crosslinker concentration levels. In this study, the film's water resistance was determined gravimetrically as well as by applying the Sircol™ Protocol. Although the reference collagen film produced without any crosslinking agents showed to have almost completely disintegrated after 2 h at 80°C, it was possible to generate chemically crosslinked films, which stayed intact after 2 h at 80°C and even maintained water resistance after 8 h at 60°C. The results of this study showed that thermal crosslinking leads to weaker bonds than the chemically crosslinking. Both assay methods for the determination of the water resistance yielded almost identical curves, except for films with an added plasticizer, clarifying that the Sircol™ protocol is not suitable to record data as a result of the dissipation of the plasticizer. Furthermore, study results indicated that the water resistance strongly depends on the amount of added crosslinker and reaches a maximum at a concentration of 10% w/w, whereas compostability was nearly 90% at 58°C within 38 days for a chemically crosslinked collagen film plasticized with lecithin. However, increased crosslinking significantly decreased the enzymatic degradability of the investigated films. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Photo‐cured organic–inorganic hybrid composites of acrylated castor oil and methacrylate‐substituted polysilsesquioxane
Authors: Shibata Mitsuhiro , Obara Syotarou 
Published: February 2012

AbstractAcrylated castor oil (ACO) was synthesized by the reaction of castor oil and acryloyl chloride in the presence of triethylamine. The 1H‐NMR and Fourier transform infrared spectral analyses of ACO showed that the hydroxy groups of castor oil are completely esterified and that the number of acrylate groups per triglyceride is 2.56. The ACO was photo‐cured with methacrylate‐substituted polysilsesquioxane (ME‐PSQ) prepared from 3‐(trimethoxysilyl)propyl methacrylate and tetramethylammonium hydroxide in the ACO/ME‐PSQ weight ratio of 20/0, 20/1, 20/2, and 20/3. Although the mechanical reinforcement effect by the incorporation of PSQ frameworks was observed when evaluated from dynamic mechanical analysis and flexural test, the reinforcement effect showed a tendency to decline with a higher ME‐PSQ content. The TEM observation revealed that the PSQ is homogeneously distributed in the matrix for the cured ACO/ME‐PSQ (20/1), while some aggregated particles of the PSQ were observed for the cured AC/ME‐PSQ (20/2). The 5% weight loss temperature of the cured ACO/ME‐PSQ rose with ME‐PSQ content. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
New Catalytic Approaches towards the Enantioselective Halogenation of Alkenes
Authors: Hennecke Ulrich 
Published: February 2012

AbstractThe addition of electrophilic reagents to the carbon–carbon double bond is one of the most fundamental reactions in organic chemistry. Halogen electrophiles constitute probably the most important class of electrophiles and have been widely used to induce electrophilic addition reactions to alkenes like halolactonizations or dihalogenations. Despite their long history and high importance, catalytic, asymmetric variants of these reactions have been underdeveloped until very recently. During the last two years this has changed and many novel approaches have been reported. This review aims to cover these new developments through discussing the common themes as well as the suggested mechanistic scenarios.
Highly Dispersed Platinum Nanoparticles on TiO2 Prepared by Using the Microwave‐Assisted Deposition Method: An Efficient Photocatalyst for the Formation of H2 and N2 from Aqueous NH3
Authors: Fuku Kojirou , Kamegawa Takashi , Mori Kohsuke , Yamashita Hiromi 
Published: February 2012

AbstractA simple and practical technique to synthesize nanosized platinum particles loaded on TiO2 (Pt–TiO2) by using a microwave (Mw)‐assisted deposition method has been exploited in the development of a highly efficient photocatalyst for the formation of H2 and N2 gases from harmful nitrogen‐containing chemical wastes, for example, aqueous ammonia (NH3). Upon Mw irradiation, a platinum precursor can be deposited quickly on the TiO2 surface from an aqueous solution of platinum and subsequent reduction with H2 affords the nanosized platinum metal particles with a narrow size distribution (Mw‐Pt–TiO2). Characterization by CO adsorption, platinum LIII‐edge X‐ray absorption fine structure analysis, and TEM analysis revealed that the size of the metal nanoparticles strongly depended on the preparation methods. Smaller platinum nanoparticles were obtained by the Mw heating method than those obtained by conventional preparation techniques, such as photoassisted deposition (PAD), impregnation (Imp), and equilibrium adsorption (EA) deposition by conventional convective heating. The H2 and N2 formation rates increased with increasing dispersity of platinum. Pt–TiO2 prepared by the Mw heating method exhibited a specifically high H2 formation activity in the photocatalytic decomposition of aqueous NH3 in a nearly stoichiometric 3:1 (H2/N2) molar ratio under inert conditions. The present Mw heating method is applicable to a variety of anatase‐type TiO2 species possessing different specific surface areas to provide small and highly dispersed platinum nanoparticles with a narrow size distribution.
Exploring self‐optimization and self‐stabilization properties in bio‐inspired autonomic cloud applications
Authors: Champrasert Paskorn , Suzuki Junichi , Lee Chonho 
Published: February 2012

SUMMARYThis paper describes an architecture to build self‐optimizable and self‐stabilizable cloud applications. The design of the proposed architecture, SymbioticSphere, is inspired by key biological principles such as decentralization, evolution, and symbiosis. In SymbioticSphere, each cloud application consists of application services and middleware platforms. Each service and platform is designed as a biological entity and implements biological behaviors such as energy exchange, migration, reproduction, and death. Each service/platform possesses behavior policies, as genes, each of which governs when to and how to invoke a particular behavior. SymbioticSphere allows services and platforms to autonomously adapt to dynamic network conditions by optimizing their behavior policies with a multiobjective genetic algorithm. Moreover, SymbioticSphere allows services and platforms to autonomously seek stable adaptation decisions as equilibria (or symbiosis) between them with a game theoretic algorithm. This symbiosis augments evolutionary optimization to expedite the adaptation of agents and platforms. It also contributes to stable performance that contains very limited amounts of fluctuations. Simulation results demonstrate that agents and platforms successfully attain self‐optimization and self‐stabilization properties in their adaptation process. Copyright © 2012 John Wiley & Sons, Ltd.
Alternative strategies of seed predator escape by early‐germinating oaks in Asia and North America
Authors: Yi Xianfeng , Yang Yueqin , Curtis Rachel , Bartlow Andrew W. , Agosta Salvatore J. , Steele Michael A. 
Published: February 2012

AbstractEarly germination of white oaks is widely viewed as an evolutionary strategy to escape rodent predation; yet, the mechanism by which this is accomplished is poorly understood. We report that chestnut oak Quercus montana (CO) and white oak Q. alba (WO) (from North America), and oriental cork oak Q. variabilis (OO) and Mongolian oak Q. mongolica (MO) (from Asia) can escape predation and successfully establish from only taproots. During germination in autumn, cotyledonary petioles of acorns of CO and WO elongate and push the plumule out of the cotyledons, whereas OO and MO extend only the hypocotyls and retain the plumule within the cotyledons. Experiments showed that the pruned taproots (>6 cm) of CO and WO acorns containing the plumule successfully germinated and survived, and the pruned taproots (≥12 cm) of OO and MO acorns without the plumule successfully regenerated along with the detached acorns, thus producing two seedlings. We argue that these two distinct regeneration morphologies reflect alternative strategies for escaping seed predation.
Influence of gem‐Dimethyl Substitution on the Stability, Kinetics and Relaxometric Properties of PDTA Complexes
Authors: Forgács Attila , Giovenzana Giovanni B. , Botta Mauro , Brücher Ernő , Tóth Imre , Baranyai Zsolt 
Published: February 2012

AbstractThe protonation constants of DMPDTA (H4DMPDTA = 2,2‐dimethylpropylenediamine‐N,N,N′,N′‐tetraacetic acid) and the stability and protonation constants of its Ln3+ and some divalent metal complexes have been determined by pH potentiometry and spectrophotometry (Cu2+) and compared with the corresponding properties of the complexes formed with PDTA (H4PDTA = propylenediamine‐N,N,N′,N′‐tetraacetic acid). The log K2H value of DMPDTA is lower by 1.5 log K units than that of PDTA. The stability constants (log KML) of the Ln3+ complexes formed with DMPDTA are lower by 1.0–1.5 log K units than those of PDTA. The kinetics of the transmetallation reactions of Gd(DMPDTA)– and Gd(PDTA)– with Cu2+ and Eu3+ have been studied by spectrophotometry. The reactions with Cu2+ and Eu3+ occur predominantly by spontaneous and proton‐assisted dissociation of the Gd(DMPDTA)– and Gd(PDTA)– complexes. The rates of the metal‐exchange reactions of Gd(DMPDTA)– are significantly lower than those of Gd(PDTA)–. The presence of the two methyl groups on the ligand backbone increases the kinetic inertness of Gd(DMPDTA)– due to the higher conformational rigidity of DMPDTA. Temperature‐dependent 17O NMR spectra and 1/T1 1H nuclear magnetic relaxation dispersion profiles of the Gd3+ complexes were measured and analyzed to obtain the parameters that influence the water exchange rate and rotational dynamics.
The effect of wind averaging time on wind erosivity estimation
Authors: Guo Zhongling , Zobeck Ted M. , Stout John E. , Zhang Keli 
Published: February 2012

ABSTRACTThe Wind Erosion Prediction System (WEPS) and Revised Wind Erosion Equation (RWEQ) are widely used for estimating wind‐induced soil erosion at a field scale. Wind is the principal erosion driver in the two models. Wind erosivity, which describes the capacity of wind to cause soil erosion, is defined as erosive wind power density (WPD) in WEPS, and wind value (W) in RWEQ. In this study, the daily average WPD (AWPD) and the daily average W (Wf) were chosen to investigate the effect of averaging time on wind erosivity estimation based on observed wind data. We compare the daily AWPD and Wf calculated from 1, 5, 10, 15, 30, and 60 minute average wind speed data.The results of comparisons indicate that averaging wind speed can significantly influence estimates of wind erosivity. Compared with the daily AWPD and Wf calculated from one minute average wind speed data, all daily AWPD and Wf values calculated from 5, 10, 15, 30, and 60 minute averaged wind speeds tend to be significantly lower than values calculated from one minute values. In general, longer averaging times tend to produce smaller values of daily AWPD or Wf, which may lead to an under‐estimation of wind erosion. Further studies are needed to extend and apply the findings obtained in this study to actual wind erosion predictions. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of soil compaction, rain exposure and their interaction on soil carbon dioxide emission
Authors: Novara Agata , Armstrong Alona , Gristina Luciano , Semple Kirk T. , Quinton John N. 
Published: February 2012

ABSTRACTSoils release more carbon, primarily as carbon dioxide (CO2), per annum than current global anthropogenic emissions. Soils emit CO2 through mineralization and decomposition of organic matter and respiration of roots and soil organisms. Given this, the evaluation of the effects of abiotic factors on microbial activity is of major importance when considering the mitigation of greenhouse gases emissions. Previous studies demonstrate that soil CO2 emission is significantly affected by temperature and soil water content. A limited number of studies have illustrated the importance of bulk density and soil surface characteristics as a result of exposure to rain on CO2 emission, however, none examine their relative importance. Therefore, this study investigated the effects of soil compaction and exposure of the soil surface to rainfall and their interaction on CO2 release. We conducted a factorial laboratory experiment with three soil types after sieving (clay, silt and sand soil), three different bulk densities (1·1 g cm–3, 1·3 g cm–3, 1·5 g cm–3) and three different exposures to rainfall (no rain, 30 minutes and 90 minutes of rainfall). The results demonstrated CO2 release varied significantly with bulk density, exposure to rain and time. The relationship between rain exposure and CO2 is positive: CO2 emission was 53% and 42% greater for the 90 minutes and 30 minutes rainfall exposure, respectively, compared to those not exposed to rain. Bulk density exhibited a negative relationship with CO2 emission: soil compacted to a bulk density of 1·1 g cm–3 emitted 32% more CO2 than soil compacted to 1·5 g cm–3. Furthermore we found that the magnitude of CO2 effluxes depended on the interaction of these two abiotic factors. Given these results, understanding the influence of soil compaction and raindrop impact on CO2 emission could lead to modified soil management practices which promote carbon sequestration. Copyright © 2012 John Wiley & Sons, Ltd.
Should bedside sonography be used first to diagnose pneumothorax secondary to blunt trauma?
Authors: Donmez Halil , Tokmak Turgut Tursem , Yildirim Afra , Buyukoglan Hakan , Ozturk Mehmet , Yaşar Ayaz Ümit , Mavili Ertugrul 
Published: February 2012

AbstractBackground.Our purpose was to evaluate the effectiveness of bedside sonography (US) in the detection of pneumothorax secondary to blunt thoracic trauma.Methods.In this prospective study, 240 hemithoraces of 120 consecutive patients with multiple trauma were evaluated with chest radiographs (CXR) and bedside thoracic US for the diagnosis of pneumothorax. CT examinations were performed in 68 patients. Fifty‐two patients who did not undergo CT examinations were excluded from the study. US examinations were performed independently at bedside by two radiologists who were not informed about CXR and CT findings. CXRs were interpreted by two radiologists who were unaware of the US and CT results. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CXR and US were calculated.Results.One hundred thirty‐six hemithoraces were assessed in 68 patients. A total of 35 pneumothoraces were detected in 33 patients. On US, the diagnosis of pneumothorax was correct in 32 hemithoraces. In 98 hemithoraces without pneumothorax, US was normal. With US examination, there were three false‐positive and three false‐negative results. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of US were 91.4%, 97%, 91.4%, 97%, and 97%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CXR were 82.7%, 89.7%, 68.5%, 95%, and 89.5%, respectively.Conclusions.Bedside thoracic US is an accurate method that can be used in trauma patients instead of CXR for the detection of pneumothorax. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012
Structure and Morphology of New Bio‐Based Thermoplastic Polyurethanes Obtained From Dimeric Fatty Acids
Authors: Bueno‐Ferrer Carmen , Hablot Elodie , Perrin‐Sarazin Florence , Garrigós M. Carmen , Jiménez Alfonso , Averous Luc 
Published: February 2012

AbstractBio‐based TPUs from dimer acid‐based polyols are synthesised by using a two‐step prepolymer process including reactive processing. The effect of the polyol on the final chemical structures, morphologies and properties of bio‐based TPUs is evaluated by different analytical techniques. It is observed that the percentage of hard segment (HS) distributed in organised and unorganised phases is a key factor to control the materials properties. DSC reveals that the percentages of HS dispersed in the soft domains are high at low experimental HS contents. Multiscale microscopies show better defined organised structures with increasing HS content in TPUs, highlighting the importance of the distribution between hard and soft segments in the material structure.magnified image
A finite element approach to the simulation of hydraulic fractures with lag
Authors: Hunsweck Michael J. , Shen Yongxing , Lew Adrian J. 
Published: February 2012

SummaryWe presented a finite‐element‐based algorithm to simulate plane‐strain, straight hydraulic fractures in an impermeable elastic medium. The algorithm accounts for the nonlinear coupling between the fluid pressure and the crack opening and separately tracks the evolution of the crack tip and the fluid front. It therefore allows the existence of a fluid lag. The fluid front is advanced explicitly in time, but an implicit strategy is needed for the crack tip to guarantee the satisfaction of Griffith's criterion at each time step. We enforced the coupling between the fluid and the rock by simultaneously solving for the pressure field in the fluid and the crack opening at each time step. We provided verification of our algorithm by performing sample simulations and comparing them with two known similarity solutions. Copyright © 2012 John Wiley & Sons, Ltd.
Blossom‐Quad: A non‐uniform quadrilateral mesh generator using a minimum‐cost perfect‐matching algorithm
Authors: Remacle J.‐F. , Lambrechts J. , Seny B. , Marchandise E. , Johnen A. , Geuzainet C. 
Published: February 2012

SUMMARYA new indirect way of producing all‐quad meshes is presented. The method takes advantage of a well‐known algorithm of the graph theory, namely the Blossom algorithm, that computes the minimum‐cost perfect matching in a graph in polynomial time. The new Blossom‐Quad algorithm is compared with standard indirect procedures. Meshes produced by the new approach are better both in terms of element shape and in terms of size field efficiency. Copyright © 2012 John Wiley & Sons, Ltd.
Online Calibration Methods for the DINA Model with Independent Attributes in CD-CAT
Authors: Chen Ping , Xin Tao , Wang Chun , Chang Hua-Hua 
Published: February 2012

AbstractItem replenishing is essential for item bank maintenance in cognitive diagnostic computerized adaptive testing (CD-CAT). In regular CAT, online calibration is commonly used to calibrate the new items continuously. However, until now no reference has publicly become available about online calibration for CD-CAT. Thus, this study investigates the possibility to extend some current strategies used in CAT to CD-CAT. Three representative online calibration methods were investigated: Method A (Stocking in Scale drift in on-line calibration. Research Rep. 88-28, 1988), marginal maximum likelihood estimate with one EM cycle (OEM) (Wainer & Mislevy In H. Wainer (ed.) Computerized adaptive testing: A primer, pp. 65–102, 1990) and marginal maximum likelihood estimate with multiple EM cycles (MEM) (Ban, Hanson, Wang, Yi, & Harris in J. Educ. Meas. 38:191–212, 2001). The objective of the current paper is to generalize these methods to the CD-CAT context under certain theoretical justifications, and the new methods are denoted as CD-Method A, CD-OEM and CD-MEM, respectively. Simulation studies are conducted to compare the performance of the three methods in terms of item-parameter recovery, and the results show that all three methods are able to recover item parameters accurately and CD-Method A performs best when the items have smaller slipping and guessing parameters. This research is a starting point of introducing online calibration in CD-CAT, and further studies are proposed for investigations such as different sample sizes, cognitive diagnostic models, and attribute-hierarchical structures.
When a product takes on characteristics of the person who created it: Sometimes it sounds sweeter
Authors: Folkes Valerie S. , Matta Shashi 
Published: February 2012

AbstractWe investigated when consumers' judgments about a product reflect information about its product source (the person who creates the product). Three experiments manipulated congruence between the source's gender and the gender‐typing of the source's product. When congruent with expectations (a male conductor played male‐typed music), pre‐trial source information had the same effect on post‐trial product judgments as when source information was absent. Incongruence (a female conductor played male‐typed music) distorted product attribute judgments when the source's competence was questioned. Her music was judged to be more delicate, less powerful and worse quality than his. This process of product experience being assimilated into incompetence stereotypes required minimal cognitive resources. When the incongruent source was undoubtedly competent, the amount of experiential evidence about an attribute influenced distortion. Consumers judged powerful music as powerful regardless of conductor gender, but, lacking much evidence about its delicacy, judged hers as more delicate than his. The selective effect of source gender information reflects consumers' cognitively effortful hypothesis testing of beliefs that gender expresses itself in a person's output against experiential evidence.
The effect of maternal fish oil supplementation during the last trimester of pregnancy on blood pressure, heart rate and heart rate variability in the 19-year-old offspring
Authors: Rytter Dorte , Christensen Jeppe H. , Bech Bodil H. , Schmidt Erik B. , Henriksen Tine B. , Olsen Sjurdur F. 
Published: February 2012

Studies in experimental animals and human subjects have suggested that intake of n-3 fatty acids in early life can affect cardiovascular risk factors in adult life. Therefore, the aim of the present study was to investigate the effect of fish oil (FO) supplementation during the third trimester of pregnancy on blood pressure (BP), heart rate (HR) and HR variability (HRV) in the 19-year-old offspring. The study was based on follow-up of a randomised, controlled trial from 1990, in which 533 pregnant women were randomised to FO, olive oil (OO) or no oil (NO) during the last trimester of pregnancy. The offspring was invited to a physical examination including BP, HR and HRV measurements. A subgroup consisting of the offspring of mothers with a low baseline fish intake also had 24 h HRV determined. The OO group was used as reference and multiple linear regression modelling was used to compare the FO and OO groups. A total of 180 of the offspring from the FO and OO groups agreed to participate in the study (45 %). The adjusted difference between the FO and OO groups was 2 (95 % CI − 1, 4) mmHg in systolic and 1 (95 % CI 0, 3) mmHg in diastolic BP. The difference in HR was 1 (95 % CI − 2, 4). Also, HRV indices did not differ significantly between groups. Hence, FO supplementation during late pregnancy was not associated with offspring BP, HR and HRV during adolescence.