bluuebunny/crossref_metadata_2025_split huggingface dataset:
Free‐radical copolymerization of 2,2,2‐trifluoroethyl methacrylate and 2,2,2‐trichloroethyl α‐fluoroacrylate: Synthesis, kinetics of copolymerization, and characterization
Authors: Cracowski Jean‐Marc , Montembault Véronique , Améduri Bruno 
Published: April 2010

AbstractCopolymers based on 2,2,2‐trifluoroethyl methacrylate (MATRIFE) and 2,2,2‐trichlororoethyl α‐fluoroacrylate (FATRICE) were synthesized in good yields by radical process initiated by tert‐butyl 2,2‐dimethylperoxypropanoate. Molar composition of the obtained poly(MATRIFE‐co‐FATRICE) copolymers were assessed by means of 1H and 19F nuclear magnetic resonance spectroscopy and by elemental analysis. The reactivity ratios, ri, of both comonomers were determined from the Kelen‐Tüdos and Finneman‐Ross methods (rMATRIFE = 1.52 ± 0.03 and rFATRICE = 0.61 ± 0.03 at 74 °C) showing unexpectedly that MATRIFE is the more reactive monomer in copolymerization. Molecular weights and polydispersity indexes of poly(MATRIFE‐co‐FATRICE) copolymers were ranging between 1.47 and 2.68 × 104 g·mol−1 and from 1.44 to 2.21, respectively. Thermal properties of the resulting polymers were examined and thermogravimetric analyses showed a satisfactory thermal stability, a thermal decomposition occurring from 220 to 295 °C as the molar ratio of FATRICE increased in the copolymer. Moreover, the glass transition temperatures of copolymers varied from 66 to 108 °C and also increased with FATRICE molar ratio in the copolymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2154–2161, 2010
Facile synthesis of fluorescent quantum dot‐polymer nanocomposites via frontal polymerization
Authors: Fang Yuan , Chen Li , Wang Cai‐feng , Chen Su 
Published: April 2010

AbstractWe report an available approach for quickly fabricating CdS QD‐polymer nanocomposites via frontal polymerization (FP). First, we synthesized (3‐mercaptopropyl)‐1‐trimethoxysilane (MPS)‐capped CdS quantum dots (QDs). With these MPS‐capped CdS QDs containing mercapto groups, MPS‐capped CdS QDs can be easily incorporated into a poly(N‐methylolacrylamide) (PNMA) matrix via FP. A variety of features for preparing QD‐polymer nanocomposites, such as initiator concentration and CdS concentration, were thoroughly investigated. The fluorescence properties of QD‐polymer nanocomposites prepared via FP are comparatively investigated on the basis of ultraviolet–visible (UV–vis) spectra and photoluminescence (PL) spectra. Results show that the PL intensity of QD‐polymer nanocomposites prepared via the FP method is superior to that obtained by the traditional batch polymerization (BP) method. In addition, by measuring the changes of PL intensity of the samples immersed in different concentrations of copper acetate solution, we found the QD‐polymer nanocomposites can be ultrasensitive to copper ions. This FP process can be exploited as a facile and rapid way for synthesis QD‐polymer nanocomposites on a large scale, avoiding the fluorescence quenching of nanocrystals during incorporation nanocrystals into polymer matrices. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2170–2177, 2010
Polyisobutylene‐based polyurethanes. V. Oxidative‐hydrolytic stability and biocompatibility
Authors: Kang Jungmee , Erdodi Gabor , Brendel Christopher M. , Ely Daniel , Kennedy Joseph P. 
Published: April 2010

AbstractThe oxidative/hydrolytic stability of polyurethanes (PUs) containing exclusively polyisobutylene (PIB), or mixed PIB/polytetramethylene oxide (PTMO), or mixed PIB/polyhexamethylene carbonate (PC) soft segments was investigated. The tensile strengths and elongations of various PUs were determined before and after agitating in 35% HNO3 or 20% H2O2/0.1 M CoCl2 solutions and retentions were quantified. The presence of PIB imparts significant oxidative/hydrolytic resistance. The tensile strength and elongation of PUs containing 70% PIB, or those of mixed PIB/PC soft segments with 50% PIB, remained essentially unchanged upon exposure to HNO3; in contrast, PUs containing mixed PIB/PTMO soft segments with 50% PIB underwent significant degradation. The tensile strength of PUs with mixed PIB/PC (60/10%) soft segment increased after exposure to HNO3, most likely because of oxidative crosslinking of PC segments. PIB/PTMO‐ and PIB/PC‐based PUs and commercially available PUs (Elast‐Eon® and Carbothane®) were exposed to H2O2/CoCl2 solutions for up to 14 weeks. Although the experimental PIB/PC‐based PUs exhibited negligible change in mechanical properties and no surface damage, Elast‐Eon® and Carbothane® showed significant surface damage. PIB‐based polyureas and Bionate® were implanted in rats for 4 weeks in vivo, and their biocompatibility was investigated. The biocompatibility of PIB‐based materials was superior to Bionate®. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2194–2203, 2010
SET‐LRP of methyl methacrylate initiated with sulfonyl halides
Authors: Fleischmann Sven , Percec Virgil 
Published: April 2010

AbstractSingle electron transfer‐living radical polymerization (SET‐LRP) represents a robust and versatile method for the rapid synthesis of macromolecules with defined architecture. The present article describes the polymerization of methyl methacrylate by SET‐LRP in protic solvent mixtures. Herein, the polymerization process was catalyzed by a straightforward Cu(0)wire/Me6‐TREN catalyst while initiation was obtained by toluenesulfonyl chloride. All experiments were conducted at 50 °C and the living polymerization was demonstrated by kinetic evaluation of the SET‐LRP. The process follows first order kinetic until all monomer is consumed which was typically achieved within 4 h. The molecular weight increased linearly with conversion and the molecular weight distributions were very narrow with Mw/Mn ∼ 1.1. Detailed investigations of the polymer samples by MALDI‐TOF confirmed that no termination took place and that the chain end functionality is retained throughout the polymerization process. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2236–2242, 2010
Design and evaluation of a dopant‐delivery system for an orthogonal atmospheric‐pressure photoionization source and its performance in the analysis of polycyclic aromatic hydrocarbons
Authors: Ehrenhauser Franz S. , Wornat Mary J. , Valsaraj Kalliat T. , Rodriguez Paul 
Published: April 2010

AbstractAtmospheric‐pressure photoionization (APPI) mass spectrometry benefits from the addition of an ionization‐enhancing dopant such as benzene. A passive dopant‐delivery system has therefore been designed for use with the orthogonal APPI source within a commercial liquid chromatographic instrument with mass spectrometric detector. By providing the dopant in the gas phase, the newly designed equipment avoids mixing problems and other difficulties associated with liquid dopant addition. The system is a simple and durable design that can reliably deliver virtually any dopant with sufficient vapor pressure in the temperature range of 20 to 120°C. At the optimum dopant flow rate (10% of the mobile phase flow rate) for high‐performance liquid chromatography with narrow‐bore (2.1 mm) columns, the system allows for uninterrupted routine analysis for up to two weeks. The performance of the device has been evaluated with benzene as dopant and with a test mixture consisting of four polycyclic aromatic hydrocarbons (PAH): naphthalene, 9H‐fluorene, anthracene, and phenanthrene. All four PAH can be detected with an excellent signal‐to‐noise ratio in the scanning mode and a limit of detection down to 0.42 ng on column (51 pg in single‐ion monitoring mode). The concentration calibration curves are linear over a range of three orders of magnitude, with correlation coefficients greater than 0.99. The utilization of benzene as dopant not only increases the sensitivity significantly – 20‐fold, compared with dopant‐free operation – but the low m/z values of the background ions observed also allow for the effective quantitative and qualitative analysis of PAH. Copyright © 2010 John Wiley & Sons, Ltd.
Using dynamic perturbations to identify fragilities in biochemical networks
Authors: Jacobsen Elling W. , Trane Camilla 
Published: April 2010

AbstractBiological functions at the cellular level result from interactions between genes, proteins and metabolites within complex biochemical reaction networks. Identifying specific and localized fragilities in such networks is important to understand the source of biological malfunctions, and to devise strategies for fighting disease states that have developed robustness. Herein we consider a method based on robust control theoretic concepts for identifying network fragilities. In particular, we consider adding static or dynamic perturbations to the network edges, i.e. the direct binary interactions within the network, and compute the smallest perturbation that induces a bifurcation, and hence a qualitative change, in the network function. The proposed method can also serve as a powerful modeling tool in that it can be used to identify parts of a model that require more detailed descriptions of the underlying processes. The method is demonstrated by application to models of sustained oscillations in the glycolytic pathway and bistability in the mitogen‐activated protein kinase (MAPK) signal transduction. Copyright © 2010 John Wiley & Sons, Ltd.
The analysis of treatment effects for recurring episodic conditions
Authors: Pullenayegum Eleanor M. , Cook Richard J. 
Published: April 2010

AbstractMany chronic disease processes feature acute episodic conditions which warrant therapeutic intervention to alleviate symptoms or reduce the risk of further complications. Examples of such disease processes arise in fields such as neurology, where migraineurs experience recurrent attacks of migraine, and respirology, where patients suffering from asthma, cystic fibrosis, or chronic obstructive pulmonary disease may experience recurrent exacerbations. In randomized clinical trials, patients suffering from diseases of this sort are often randomized to one of several treatments and followed over a fixed period of time, during which any episodes are treated with the assigned treatment. When the outcome of interest is a response to treatment at each episode, the data have a similar structure to longitudinal data from studies with prescheduled follow‐up assessments, and it is commonplace for analyses to be based on the corresponding methodology. However, this approach ignores the fact that the timing of episodes, and hence the number observed in any given period, is stochastic. In this tutorial we demonstrate the biases that result from naive analyses, discuss analyses that account for the complete stochastic nature, and use a recent migraine trial for illustration. We conclude with some considerations for the design of randomized trials where the unit of analysis is the episode rather than the patient. Copyright © 2010 John Wiley & Sons, Ltd.
Joint modeling of progression‐free survival and death in advanced cancer clinical trials
Authors: Dejardin David , Lesaffre Emmanuel , Verbeke Geert 
Published: April 2010

AbstractProgression‐related endpoints (such as time to progression or progression‐free survival) and time to death are common endpoints in cancer clinical trials. It is of interest to study the link between progression‐related endpoints and time to death (e.g. to evaluate the degree of surrogacy). However, current methods ignore some aspects of the definitions of progression‐related endpoints. We review those definitions and investigate their impact on modeling the joint distribution. Further, we propose a multi‐state model in which the association between the endpoints is modeled through a frailty term. We also argue that interval‐censoring needs to be taken into account to more closely match the latent disease evolution. The joint distribution and an expression for Kendall's τ are derived. The model is applied to data from a clinical trial in advanced metastatic ovarian cancer. Copyright © 2010 John Wiley & Sons, Ltd.
Case study and analogue methodologies in climate change vulnerability research
Authors: Ford James D. , Keskitalo E. C. H. , Smith Tanya , Pearce Tristan , Berrang‐Ford Lea , Duerden Frank , Smit Barry 
Published: April 2010

AbstractAssessing vulnerability is an important component of human dimensions of climate change (HDCC) research. Vulnerability assessments identify and characterize who and what are sensitive to climatic risks and why, characterize adaptive capacity and its determinants, and identify opportunities for adaptation. This paper examines the importance of case study and analogue methodologies in vulnerability research, reviews the historical evolution of the two methodologies in the HDCC field, and identifies ways in which they can be used to increase our understanding of vulnerability. Case studies involve in‐depth place‐based research that focuses on a particular exposure unit (e.g., community, industry, etc.) to characterize vulnerability and its determinants. Temporal analogues use past and present experiences and responses to climatic variability, change and extremes to provide insights for vulnerability to climate change; spatial analogues involve conducting research in one region and identifying parallels to how another region might be affected by climate change. Vulnerability research that uses case studies and analogues can help to develop an understanding of the determinants of vulnerability and how they interact, and identify opportunities to reduce vulnerability and enhance adaptive capacity to current and future climate risks. This information can assist policy makers in developing adaptation plans and to mainstream climate change adaptation into other policy‐ and decision‐making processes. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:Vulnerability and Adaptation to Climate Change > Learning from Cases and Analogies
Embodiment as a unifying perspective for psychology
Authors: Glenberg Arthur M. 
Published: April 2010

AbstractA basic claim of the embodiment framework is that all psychological processes are influenced by body morphology, sensory systems, motor systems, and emotions. As such, the framework holds the promise of providing a unifying perspective for psychological research. This article begins with a sketch of several arguments, from evolution to philosophy, as to why the embodiment framework is a good bet. These arguments are followed by a review of approaches to embodiment, including those from cognitive linguistics, perceptual symbol theory, and action‐based theories. Finally, examples are provided for how a unifying perspective might work for cognition (including language and memory), cognitive and social development, social psychology, neuroscience, clinical psychology, and psychology applied to education. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:

Psychology > Theory and Methods
Tree‐structured classifiers
Authors: Loh Wei‐Yin 
Published: April 2010

AbstractA tree‐structured classifier is a decision tree for predicting a class variable from one or more predictor variables. THAID was the first such algorithm. This article focuses on the classification and regression trees CART® C4.5, and GUIDE methods. The algorithms are briefly reviewed and their similarities and differences are compared on a real data set and by simulation. Copyright © 2010 John Wiley & Sons, Inc.This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Classification and Regression Trees (CART)
More carrots than sticks: Antanas Mockus's civic culture policy in Bogotá
Authors: Buendía Felipe Cala 
Published: April 2010

AbstractThe son of a Lithuanian artist, Antanas Mockus was the president of the National University in Colombia before he became mayor of Bogotá in 1995. As mayor, he transformed the city into a huge classroom, not only bringing to his administration a new view of governing but also transforming the way people exercised their citizenship. Mockus resorted to a creative communicative and pedagogical effort to change the citizens' hearts and minds in favor of peaceful coexistence and legal compliance. Symbols, metaphors, and humor became the language through which the administration would enforce its measures to deal with urban violence. Unconventional techniques, such as a symbolic vaccine against domestic violence and the use of mimes to control traffic circulation and create a sense of shame among those who committed infractions, helped to stop crime and develop a new sense of citizenship.
Silent gains: Instituto Buena Bista and art as catalyst among Curaçaoan youth
Authors: González Iberia Pérez 
Published: April 2010

AbstractConsidering the limited opportunities and resources for creative education, artists David Bade and Tirzo Martha, along with art historian Nancy Hoffmann, developed a dynamic platform to support creative young talent on the Dutch Caribbean island of Curaçao. The aim of Instituto Buena Bista (IBB), founded in 2006, is to strengthen the arena of culture and the visual arts by offering young Curaçaoans a basic but thorough course in art education that is meant to function as a springboard to more advanced art schools. With only two years of operation, the IBB is already seeing how some of its students go to art academies abroad and participate in art contests in the Netherlands. An exploration of how the IBB is filling up a cultural void by proposing an alternative to local youth education that allows them to develop a buena bista—a new and different view of their island, their futures, and themselves.
The Beat of Boyle Street: Empowering Aboriginal youth through music making
Authors: Wang Elaine L. 
Published: April 2010

AbstractAn irrepressibly popular musical phenomenon, hip‐hop is close to spoken word and focuses on lyrics with a message, reviving local traditions of song that tell histories, counsel listeners, and challenge participants to outdo one another in clever exchanges. A hip‐hop music‐making program in Edmonton, Canada, successfully reengages at‐risk Aboriginal youth in school with high levels of desertion and helps them establish a healthy sense of self and of their identity as Aboriginals.
Music as social medicine: Two perspectives on the West‐Eastern Divan Orchestra
Authors: Washington David M. , Beecher Devin G. 
Published: April 2010

AbstractThe social power of music can effect stable and positive changes in individual health and communities that have significant health risks. Two observers, a medical student and a music student, discuss respectively the ideals and challenges of this principle put into practice. Their reflections about the role of music as social therapy and space for cultural communication stem from their one‐week involvement with the West‐Eastern Divan Orchestra at its summer institute in Spain.
Boal's Theater of the Oppressed and how to derail real‐life tragedies with imagination
Authors: Schaedler Maria Tereza 
Published: April 2010

AbstractIn the 1960s, Augusto Boal created a process whereby audience members could stop a performance and suggest different actions for the actors, who would then carry out the audience's suggestions. Then, he began inviting audience members onto the stage to demonstrate their ideas and discovered that through their participation they become empowered not only to imagine change but also to practice it and generate social action. The author studied with him and shares with us her own expertise as a practicing artist and educator of youth and adult immigrants, using Boal's revolutionary methods.
Das neue Neodym(III)‐Oxidchlorid‐Oxoselenat(IV) Nd7O5Cl3[SeO3]4
Authors: Zitzer Sabine , Schleid Thomas 
Published: April 2010

AbstractPale violet, needle‐shaped single crystals of the new neodymium(III) oxide chloride oxoselenate(IV) Nd7O5Cl3[SeO3]4 were obtained by the reaction of Nd2O3 and NdCl3 with SeO2 (molar ratio: 3:1:4) in evacuated silica ampoules within seven days at 775 °C, if an excess of CsCl worked as fluxing agent. Nd7O5Cl3[SeO3]4 crystallizes in the triclinic space group P$\bar{1}$ with the lattice parameters a = 694.46(4), b = 944.53(5), c = 1567.92(9) pm, α = 87.821(3), β = 81.849(3), γ = 84.852(3)° and Z = 2. Its structure exhibits seven crystallographically different Nd3+ cations, of which (Nd1)3+ – (Nd4)3+ are coordinated by O2– anions forming distorted square prisms. The polyhedra of (Nd1)3+ and (Nd2)3+ receive additional caps by one Cl– anion each, and (Nd5)3+ – (Nd7)3+ show mixed square antiprismatic environments of O2– and Cl– anions too. However, the polyhedra of (Nd5)3+ and (Nd6)3+ include two, the polyhedron about (Nd7)3+ even three Cl– anions. Two‐dimensional ${}^2_\infty \{[\textrm{O}_5\textrm{Nd}_7]^{11+}\}$ layers of edge‐ and vertex‐linked [ONd4]10+ tetrahedra are built up by (O1)2– – (O5)2– together with all Nd3+ cations. All the other oxygen atoms belong to four crystallographically different Se4+ cations erecting ψ1‐tetrahedral oxoselenate(IV) units [SeO3]2– with stereochemically active non‐bonding electron pairs (“lone pairs”) pointing into the free space between the ${}^2_\infty \{[\textrm{O}_5\textrm{Nd}_7]^{11+}\}$ layers. Three independent Cl– anions in threefold coordination of Nd3+ cations interconnect the ${}^2_\infty \{([\textrm{O}_5\textrm{Nd}_7][\textrm{SeO}_3]_4)^{3+}\}$ layers to form a three‐dimensional network, thereby achieving the charge balance.
Structural Effects of Cu/Zn Substitution in the Malachite–Rosasite System
Authors: Behrens Malte , Girgsdies Frank 
Published: April 2010

AbstractSynthetic zincian malachite samples (Cu1–xZnx)2(OH)2CO3withx= 0, 0.1, 0.2 and 0.3 were characterized by powder X‐ray diffraction and optical spectroscopy. The XRD patterns of the samples up tox= 0.2 indicate single phase materials with an approximately linear dependence of the refined lattice parameters on the zinc content. In contrast, the sample with a nominal zinc contentx= 0.3 shows the formation of a small amount of aurichalcite (Zn,Cu)5(OH)6(CO3)2as an additional phase. Based on the lattice parameter variations, the zinc content of the zincian malachite component in this sample is estimated to bex≈︁ 0.27, which seems to represent the maximum possible substitution in zincian malachite under the synthesis conditions applied. The results are discussed in relation to preparation of Cu/ZnO catalysts and the crystal structures of the minerals malachite and rosasite. One striking difference between these two structurally closely related phases is the orientation of the Jahn–Teller elongated axes of the CuO6octahedra in the unit cell, which seems to be correlated with the placement of the monoclinicβangle. The structural and chemical relationship between these crystallographically distinct phases is discussed using a hypothetical intermediate Zn2(OH)2CO3phase of higher orthorhombic symmetry. In addition to the crystallographic analysis, optical spectroscopy proves to be a useful tool for estimation of the Cu:Zn ratio in (Cu1–xZnx)2(OH)2CO3samples.