bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structures ofN-(arenecarbonyl)-N,N′-dicyclohexylureas, cyclohexyl-NH—C(O)—N(cyclohexyl)—C(O)Ar, (Ar = Ph, pyridin-3-yl and pyrazinyl)
Authors: Pinheiro Alessandra , de Souza Marcos V. N. , Wardell James L. , Wardell Solange M. S. V. 
Published: January 2012

AbstractThe crystal structures of threeN-(arenecarbonyl)-N,N′-dicyclohexylureas, [1: ArCO-N(cyclohexyl)-CO-NH-cyclohexyl: (R = Ph (1a), pyridin-3-yl (1c) and pyrazinyl (1e)] are reported from data collected at 120K. Comparison of the new findings with published data for the three compounds indicates three forms have been recognized for this group of compounds: anorthorhombic-form [P212121] and twotriclinic[P-1] forms –triclinic-Iandtriclinic-II.Orthorhombicandtriclinic-IIphases have been determined for compound,1a,triclinic-Iandtriclinic-IIforms for compound1c, and just theorthorhombicform for compound,1e. Orthorhombic1aand1eare isostructural, as aretriclinic-II1aand1c. The asymmetric unit for theorthorhombicform contains just a single molecule, while the molecules are linked into chains,C(7)R22(11),viastrong N—H ··· Oand weaker C—H ··· O intermolecular hydrogen bonds. The asymmetric unit fortriclinic-Iconsists of two independent molecules, molecules A and B, which are linked alternatively into chains,C(8)R22(16),viaN—H ··· N and C—H ··· O intermolecular hydrogen bonds in the direction of theaaxis: such chains are linkedviaC—H ··· O hydrogen bonds. The asymmetric unit of thetriclinic-IIphase also comprises two independent molecules, molecules A and B, which are also linked alternatively into chains,C(8), but onlyviaN—H ··· O hydrogen bonds, with other intermolecular interactions of the C—H ··· π type also present.
Effects of Timing and Level of Degree Attained on Depressive Symptoms and Self-Rated Health at Midlife
Authors: Walsemann Katrina M. , Bell Bethany A. , Hummer Robert A. 
Published: January 2012

Objectives. We examined whether attaining a higher educational degree after 25 years of age was associated with fewer depressive symptoms and better self-rated health at midlife than was not attaining a higher educational degree. Methods. We analyzed data from National Longitudinal Survey of Youth, restricting our sample to respondents who had not attained a bachelor's degree by 25 years of age (n = 7179). We stratified all regression models by highest degree attained by 25 years of age. Results. Among respondents with no degree, a high school diploma, or a post–high school certificate at 25 years of age, attaining at least a bachelor's degree by midlife was associated with fewer depressive symptoms and better self-rated health at midlife compared with respondents who did not attain a higher degree by midlife. Those with an associate's degree at 25 years of age who later attained a bachelor's degree or higher reported better health at midlife. Conclusions. Attaining at least a bachelor's degree after 25 years of age is associated with better midlife health. Other specifications of educational timing and its health effects across the life course should be studied.
Determining the Clinical Utility of the Short Child Occupational Profile (SCOPE)
Authors: Bowyer Patricia , Lee Jenica , Kramer Jessica , Taylor Renee R , Kielhofner Gary 
Published: January 2012

Objective: The purpose of this study was to propose a process for the study of clinical utility and to illustrate its implementation in the development of an assessment. Method: A mixed methods approach was used to understand the clinical utility of an assessment in development. An exploratory qualitative/quantitative (QUAL?QUANT) approach was used to identify perspectives of the clinical utility of the assessment. The design placed equal status on the two methods used: focus groups and surveys. Results: The proposed process for the study of clinical utility resulted in targeted revisions based upon data obtained from 21 practitioners in three focus groups during a systemised examination of clinical utility. Conclusion: A mixed methods process can be used to ensure the clinical utility of assessments during the development process.
Palladium‐Catalyzed Carbonylation of Amines: Switchable Approaches to Carbamates and N,N′‐Disubstituted Ureas
Authors: Guan Zheng‐Hui , Lei Hao , Chen Ming , Ren Zhi‐Hui , Bai Yinjuan , Wang Yao‐Yu 
Published: January 2012

AbstractSwitchable access to carbamates and ureas has been developed by solvent control palladium‐catalyzed carbonylation of aromatic amines under an atmosphere of carbon monoxide. A variety of N‐phenylcarbamates and N,N′‐diphenylureas was easily synthesized in good to excellent yields from readily available aromatic amines under mild conditions.
Facile Preparation and Reactivity of Magnetic Nanoparticle‐ Supported Hypervalent Iodine Reagent: A Convenient Recyclable Reagent for Oxidation
Authors: Zhu Chenjie , Wei Yunyang 
Published: January 2012

AbstractA simple three‐step preparation of magnetic nanoparticle‐supported (diacetoxyiodo)benzene starting from 4‐iodobenzoic acid is described. The nanoparticle reagent was obtained with good loading levels and has been successfully used for efficient oxidation of a wide range of alcohols. The supported reagent demonstrated comparable activity with that of its homogeneous counterpart (diacetoxyiodo)benzene and could be simply recycled with the assistance of an external magnet.
Die Umprogrammierung des genetischen Codes: vom Triplett‐ zum Quadruplettcode
Authors: Wang Kaihang , Schmied Wolfgang H. , Chin Jason W. 
Published: January 2012

AbstractDer genetische Code lebender Zellen ist nahezu universell ein Triplettcode. Zelluläre Ribosomen so zu verändern, dass sie auch andere als Triplettcodes ablesen können, stellt eine große Herausforderung dar, da viele ribosomale Mutationen letal sind. In diesem Kurzaufsatz diskutieren wir den Einbau nichtnatürlicher Aminosäuren in Proteine durch Ablesen von Quadruplettcodons sowie die Entwicklung eines orthogonalen Translationssystems in der Zelle, das sich eines evolvierten orthogonalen Ribosoms bedient, um durch Ablesen von Quadruplettcodons in effizienter Weise den Einbau nichtnatürlicher Aminosäuren in Proteine zu dirigieren. Durch Verwendung dieses Systems gelang der Einbau von multiplen nichtnatürlichen Aminosäuren, um rekombinante Proteine auf genetischem Wege mit emergenten Eigenschaften auszustatten. Die Ausweitung dieses Ansatzes könnte die kombinatorische Biosynthese von Materialien und Therapeutika möglich machen und darüber hinaus die Erforschung der Frage anspornen, ob sich Lebensformen mit zusätzlichen genetisch codierten Polymeren entwickeln könnten, die Aufgaben erfüllen, die natürliche biologische Systeme nicht ausführen.
Effect of reactive blocked polyisocyanate on the properties of solvent cast blends from poly(lactic acid) and poly(ethylene glycol)
Authors: Shen Tengfei , Lu Mangeng , Zhou Dewen , Liang Liyan 
Published: January 2012

AbstractPoly(lactic acid) (PLA)/poly(ethylene glycol) (PEG) blends containing reactive ethyl cellosolve‐blocked polyisocyanate (EC‐bp) as a crosslinking agent with the goal of making sustainable “eco‐friendly materials” were prepared using solvent casting method. Effects of such crosslinking agent and PEG additive on the properties of the prepared blends were investigated and compared. The morphology of the blends, evaluated by environmental scanning electron microscopy (ESEM), indicated that improved interfacial adhesion between PLA and PEG were achieved by the crosslinking effect of EC‐bp. Tensile properties and water resistance were also studied and the results showed that these properties of EC‐bp modified blends were significantly enhanced in comparison with the unmodified ones. Differential scanning calorimetry (DSC) and X‐ray diffraction (XRD) results showed that the degree of crystallinity (χc) of the blends was enhanced in the presence of PEG domains, whereas crystallization rate was decreased by addition of EC‐bp. Dynamical mechanical analysis (DMA) showed that enhanced storage modulus and heat resistance of the blends were obtained when EC‐bp was introduced as a crosslinking agent. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Copolymerization of ethylene with α‐olefins over supported titanium–magnesium catalysts. II. Comonomer as a chain transfer agent
Authors: Nikolaeva Marina I. , Matsko Mikhail A. , Mikenas Tatiana B. , Echevskaya Ludmila G. , Zakharov Vladimir A. 
Published: January 2012

AbstractThe data on the effect of comonomer (propylene and 1‐hexene) on molecular weight (Mw), molecular weight distribution (MWD), and content of terminal double bonds were obtained for ethylene/α‐olefin copolymers produced over a supported titanium–magnesium catalyst (TMC) upon polymerization in the absence of hydrogen. The experimental data on the effect of comonomer concentration on Mw of polymers were used to calculate the ratios between the effective rate constants of chain transfer with monomer and the propagation rate constant. It was shown that the effective rate constant of chain transfer with monomers increases in the row of monomers: ethylene < 1‐hexene < propylene. Meanwhile, the data on the effect of copolymers on content of terminal double bonds of various types demonstrate that different reactions of chain transfer with comonomer may simultaneously occur during copolymerization. It results in simultaneous formation of terminal vinylidene and trans‐vinylene bonds. Therefore, the calculated rate constants of chain transfer with comonomer are complex values, which include the rate constants of chain transfer with comonomer occurring via different mechanisms. The data on MWD, short chain branching (SCB) and terminal double bonds content of different types were obtained by molecular weight fractionation of copolymers followed by the analysis of narrow fractions. The analysis of the data on MWDs of SCB and terminal double bonds shows that active sites of the TMC are considerably heterogeneous with respect to the rates of different chain transfer reactions with monomers. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Antielectrostatic agent addition in low‐dielectric‐constant polymerization media
Authors: Bayat Mohammad Hossein , Abdouss Majid 
Published: January 2012

AbstractIn the coordinative polymerization of α‐olefin by a slurry process, a low‐dielectric‐constant suspending agent, such as hexane or heptane, must be used. As a result of solvent movement and its friction between system components, electrostatic charges are generated. Because of low electrical conduction of these solvents, the generated charges accumulate in the polymerization medium. Consequently, a repulsive force between same charges effects the growth of the polymer particles and causes them to form fine particles. In this article, we present research results on the effects of antielectrostatic agents on the increase of the electrical conduction of the polymerization medium, particle size distribution, and also the quantity of fine particles in the final polymer. Techniques gained from the fuel industry were applied to modify the subjected polymerization medium. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Use of flux pre‐analysis to enable 13C tracer studies in pyruvate kinase‐deficient Escherichia coli
Authors: Meade Jonathan , Khan Saleem , Ataai Mohammad , Domach Michael 
Published: January 2012

AbstractPyruvate kinase‐deficient Escherichia coli (PB25) is a low by‐product‐producing yet fast‐growing mutant that has been shown to have technological potential. Determining the flux limits through finding the extreme point flux sets was previously reported to identify alternate metabolite trafficking scenarios. Previously, the extreme point flux sets were used to design tracer experiments; however, variation in extracellular measurements was not considered, and reaction reversibility was assumed to be low to moderate. In this study, we examined the utility of limiting the fluxes and predetermining the trafficking scenarios in PB25, including confirmation of quasi‐linearity between extreme points to ensure sensitivity is maintained. The effects of variation in extracellular measurements and reaction reversibilities were also examined. Tightened flux limits reduced the nonlinearity between label distribution and fluxes. For low to moderate reversibility, contrast was also preserved. However, for highly reversible phosphoglucoisomerase activity, information from common analytes could lead to a flux solution that is biased towards one extreme point. Based on the PB25 model, some suggestions are provided for how predetermining flux limits and trafficking scenarios could enable flux identification in larger network problems.
Systematic review and meta-analysis of randomized clinical trials of self-expanding metallic stents as a bridge to surgery versus emergency surgery for malignant left-sided large bowel obstruction
Authors: Tan C J , Dasari B V M , Gardiner K 
Published: January 2012

Abstract

Background
Use of self-expanding metallic stents (SEMS) as a bridge to surgery has been suggested as an alternative management for acute malignant left-sided colonic obstruction, as emergency surgery has a high risk of morbidity and mortality. This meta-analysis evaluated high-quality evidence comparing preoperative SEMS with emergency surgery.

Methods
Relevant randomized clinical trials (RCTs) were identified from the Cochrane Central Register of Controlled Trials, MEDLINE, Embase and PubMed (1990–2011). Primary outcomes were primary anastomosis, stoma and in-hospital mortality rates. Secondary outcomes included anastomotic leak, 30-day reoperation and surgical-site infection rates.

Results
Four RCTs with 234 patients were included. Technical and clinical success rates for stenting were 70·7 per cent (82 of 116) and 69·0 per cent (80 of 116) respectively. The clinical perforation rate was 6·9 per cent (8 of 116) and the silent perforation rate 14 per cent (11 of 77). SEMS intervention resulted in significantly higher successful primary anastomosis (risk ratio (RR) 1·58, 95 per cent confidence interval 1·22 to 2·04; P &lt; 0·001) and lower overall stoma (RR 0·71, 0·56 to 0·89; P = 0·004) rates. There was no difference in primary anastomosis, permanent stoma, in-hospital mortality, anastomotic leak, 30-day reoperation and surgical-site infection rates. Three trials were stopped prematurely, one because the emergency surgery group had a significantly increased anastomotic leak rate, and two others because of stent-related complications and increased 30-day morbidity following SEMS management.

Conclusion
Technical and clinical success rates for stenting were lower than expected. SEMS is associated with a high incidence of clinical and silent perforation. However, as a bridge to surgery, SEMS has higher successful primary anastomosis and lower overall stoma rates, with no significant difference in complications or mortality.
Do the Psychopathic Personality Traits of Fearless Dominance and Self‐Centered Impulsivity Predict Attitudes about and Influences on Research Participation?
Authors: Smith Shannon Toney , Edens John F. , Epstein Monica , Stiles Paul G. , Poythress Norman G. 
Published: January 2012

AbstractLittle is known about potential participants' views about research, their willingness to participate in research, and the extent to which they might be susceptible to coercive attempts to compel their participation, particularly among populations at risk for exploitation (e.g., offenders). The extent to which individual differences variables, such as personality constructs (e.g., psychopathic traits), might affect participants' attitudes toward research is also essentially unknown. The present study sought to examine the psychopathy constructs of Fearless Dominance (FD) and Self‐Centered Impulsivity (SCI) via the Multidimensional Personality Questionnaire‐Brief Form (MPQ‐BF) to assess the extent to which these traits predict attitudes towards research and susceptibility to coercion within a diverse criminal justice sample (N = 631). SCI was modestly associated with perceptions that illicit pressures regarding research participation were likely to occur, and participants high in these traits appeared somewhat vulnerable to succumbing to coercive influences. In contrast, FD failed to predict the likelihood that illicit pressures regarding research participation would occur as well as the potential that these pressures would have to impact participants' voluntariness and likelihood of participating. Implications for recruiting potential participants for research in correctional settings are discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Arp@: Remote experiences with real embedded systems
Authors: Vilajosana Xavier , Llosa Jordi , Vilajosana Ignasi , Prieto‐Blàzquez Josep 
Published: January 2012

ABSTRACTThe emergence of the Internet of Things increases the demand on embedded computer systems, which in turn requires the availability of specialized engineers in the near future. Several universities commenced embedded‐systems programming courses to complement students' skills by introducing specific firmware development techniques. Hands‐on labs with real hardware interaction is restricted to the time students are in the laboratory whilst virtual‐laboratories provide more flexibility at the caveat that students do not improve hardware manipulation skills as they cannot physically inter‐actuate with real devices. We argue that students' abilities can be increased by providing them with a sensor board with reduced computation and communication capabilities to work with at home. Students increase the time spent manipulating the device; moreover, their motivation is also increased as they can put their effort on developments of their interest. The article presents the experience carried out at the virtual‐course of Embedded‐Systems at the UOC. The developed technology, the methodology, and the feedback from students are presented here, and corroborate the benefits of the chosen methodology.© 2012 Wiley Periodicals, Inc. Comput Appl Eng Educ 22:639–648, 2014; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21555
Novel Capsular Aggregates from Flexible Tripodal Triureas with Cs Symmetry
Authors: Alajarin Mateo , Orenes Raul‐Angel , Howard Judith A. K. , Spencer Elinor C. , Steed Jonathan W. , Pastor Aurelia 
Published: January 2012

AbstractTris(2‐ and 3‐ureidobenzyl)amines with Cs symmetry self‐assemble in solution forming mixtures of regioisomeric capsular aggregates, one of which is chiral and the other centrosymmetric. Under certain conditions, a predominance of the centrosymmetric regioisomer is found before equilibrium, that is, a mixture close to the statistical ratio of the two species is reached. In the solid state, there is a preference for the centrosymmetric capsules. Molecular models of both regioisomeric aggregates have been built and analyzed for comparison. Guests inside capsules formed by self‐assembly of desymmetrized tris(3‐ureidobenzyl)amines feel different magnetic environments, depending on whether they are inside a chiral or an achiral regioisomeric container. Of special significance are the experiments with a more flexible triurea endowed with an ureidopropylic arm, which self‐assembles with the same efficiency as the more rigid tris(ureidobenzyl)amines.
Growth Behavior and Kinetics of Self‐Assembled Silica–Carbonate Biomorphs
Authors: Kellermeier Matthias , Melero‐García Emilio , Glaab Fabian , Eiblmeier Josef , Kienle Lorenz , Rachel Reinhard , Kunz Werner , García‐Ruiz Juan Manuel 
Published: January 2012

AbstractUpon slow crystallization from silica‐containing solutions or gels at elevated pH, alkaline‐earth carbonates spontaneously self‐assemble into remarkable nanocrystalline ultrastructures. These so‐called silica biomorphs exhibit curved morphologies beyond crystallographic symmetry and ordered textures reminiscent of the hierarchical design found in many biominerals. The formation of these fascinating materials is thought to be driven by a dynamic coupling of the components’ speciations in solution, which causes concerted autocatalytic mineralization of silica‐stabilized nanocrystals over hours. In the present work, we have studied the precipitation kinetics of this unique system by determining growth rates of individual aggregates using video microscopy, and correlated the results with time‐dependent data on the concentration of metal ions and pH acquired online during crystallization. In this manner, insight to the evolution of chemical conditions during growth was gained. It is shown that crystallization proceeds linearly with time and is essentially reaction controlled, which fits well in the proposed morphogenetic scenario, and thus, indirectly supports it. Measurements of the silica concentration in solution, combined with analyses of crystal aggregates isolated at distinct stages of morphogenesis, further demonstrate that the fraction of silica coprecipitated with carbonate during active growth is rather small. We discuss our findings with respect to the role of silica in the formation of biomorphs, and moreover, prove that the external silica skins that occasionally sheath the aggregates—previously supposed to be involved in the growth mechanism— originate from secondary precipitation after growth is already terminated.
High‐TC Ferromagnetic Semiconductor‐Like Behavior and Unusual Electrical Properties in Compounds with a 2×2×2 Superstructure of the Half‐Heusler Phase
Authors: Xiong Ding‐Bang , Okamoto Norihiko L. , Waki Takeshi , Zhao Yufeng , Kishida Kyosuke , Inui Haruyuki 
Published: January 2012

AbstractHeusler phases, including the full‐ and half‐Heusler families, represent an outstanding class of multifunctional materials on account of their great tunability in compositions, valence electron counts (VEC), and properties. Here we demonstrate a systematic design of a series of new compounds with a 2×2×2 superstructure of the half‐Heusler unit cell in X–Y–Z (X=Fe, Ru, Co, Rh, Ir; Y=Zn, Mn; Z=Sn, Sb) systems. Their structures were solved by using both powder and single‐crystal X‐ray diffraction, and also directly observed by using high‐angle annular dark‐field imaging in a scanning transmission electron microscope (HAADF‐STEM). The VEC values of these new compounds span a wide and continuous range comparable to those for the full‐ and half‐Heusler families, thereby implying tunability in compositions and physical properties in the superstructure. In fact, we observed abnormal electrical properties and a ferromagnetic semiconductor‐like behavior with a high and tunable Curie temperature in these superstructures.
Accurate solution for acceleration motion of a vertically falling spherical particle in incompressible newtonian media
Authors: Torabi Mohsen , Yaghoobi Hessameddin 
Published: January 2012

AbstractIn this paper, the acceleration motion of a vertically falling spherical particle in incompressible Newtonian media was investigated. The instantaneous velocity and acceleration were carried out using analytical solution technique i.e. the differential transformation method (DTM). Using the DTM, the non‐linear constrained governing equations were reduced to recurrence relations and related initial conditions were transformed into a set of algebraic equations. The solutions were subsequently solved by a process of inverse transformation. The results were also compared with those derived from the homotopy perturbation method (HPM), closed‐form solution, the established fourth order Runge–Kutta method and experimental data in order to verify the accuracy of the proposed method. It was found that this method can achieve more accurate results compared with the HPM. © 2012 Canadian Society for Chemical Engineering