bluuebunny/crossref_metadata_2025_split huggingface dataset:
Poly(ethylene glycol)‐based amphiphilic model conetworks: Synthesis by RAFT polymerization and characterization
Authors: Achilleos Mariliz , Legge Thomas M. , Perrier Sébastien , Patrickios Costas S. 
Published: October 2008

AbstractPoly(ethylene glycol) (PEG)‐containing quasi‐model amphiphilic polymer conetworks (APCNs) were prepared by reversible addition fragmentation chain transfer (RAFT) polymerization using α,ω‐bis(2‐cyanoprop‐2‐yl dithiobenzoate)‐PEG as a bifunctional RAFT macrochain transfer agent (macro‐CTA) and stepwise additions of a hydrophobic monomer and a crosslinker (crosslinker: macro‐CTA = 10:1, reaction time 24 h). Three different types of monomers, methyl methacrylate (MMA), n‐butyl acrylate and styrene, were employed as the hydrophobic monomers, whereas ethylene glycol dimethacrylate, ethylene glycol diacrylate and 1,4‐divinylbenzene served as the respective crosslinkers. PEG homopolymer hydrophilic quasi‐model networks were also prepared by RAFT‐polymerizing the three crosslinkers directly onto the two active ends of the PEG‐based macro‐CTA. From the three ABA triblock copolymers prepared, the MMA‐containing one was obtained at the highest polymerization yields. The crosslinking yields of the three ABA triblock copolymers with the corresponding crosslinkers were higher than those of the PEG‐based macro‐CTA with the same crosslinkers. The degrees of swelling (DSs) of all conetworks were measured in water and in tetrahydrofuran (THF). The DSs of the APCNs in THF were higher than those in water, whereas the reverse was true for the DSs of the hydrophilic homopolymer networks. Finally, the aqueous DSs of the APCNs were lower than those of the corresponding hydrophilic homopolymer networks. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7556–7565, 2008
Exploring rheological properties of aqueous polyaniline‐PVP dispersion
Authors: Gangopadhyay Rupali 
Published: October 2008

AbstractStable aqueous dispersion of polyaniline (PAn) stabilized by a hydrophilic polymer poly(vinyl pyrrolidone) (PVP) exhibits interesting rheological properties different from its components. Shear thinning observed for both PVP and PAn–PVP colloid (PP) indicates partially entangled nature of the later. Linear viscoelastic response of PVP solution exhibit strong frequency dependence of elastic (G′) and viscous (G″) modulus over the whole frequency range (0.1–100 ras/s) where G′ never exceeds G″ indicating the applicability of the Rouse‐Zimm model to this system. On the other hand, there is a crossover of G′ and G″ in the rheological profile of PP dispersion so that a single relaxation time model can be applicable. Therefore, PVP presents an entangled polymeric system and supposed to have a spectrum of relaxation times, whereas PP resembles to a physically crosslinked system with a single relaxation time. Increasing the extent of hydrogen bonding within the system (by raising the fraction of PAn or by leaving the solution undisturbed for long) relaxation time also becomes longer. The large difference in values of steady and complex shear viscosity (η and η*) within LVE regime reflects that original Cox‐Merz rule is obviously inapplicable to these systems. But at larger strain amplitude, η and η* are satisfactorily coincident that indicates a broader applicability of the modified Cox‐Merz rule. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2443–2455, 2008
Synthesis and aqueous solution properties of hydrophobically modified anionic acrylamide copolymers
Authors: Yang Qingbo , Song Chunlei , Chen Qiang , Zhang Pingping , Wang Pixin 
Published: October 2008

AbstractIn this investigation, hydrophobically modified polyacrylamide with low amounts of anionic long‐chain alkyl was synthesized by the free radical polymerization in deionized water. This water‐soluble copolymerization method is more convenient compared with the traditional micellar copolymerization methods. The copolymers were characterized using Fourier transform infrared, 1H NMR, and the molecular weight and polydispersity were determined using gel permeation chromatography. The solution behavior of the copolymers was studied as a function of composition, pH, and added electrolytes. As NaCl was added to solutions of AM/C11AM copolymers or pH was lowered, the shielding or elimination of electrostatic repulsions between carboxylate groups of the C11AM unit lead to coil shrinkage. The steady shear viscosity and dynamic shear viscoelastic properties in semidilute, salt‐free aqueous solutions were conducted to examine the concentration effects on copolymers. In addition, the shear superimposed oscillation technique was used to probe the structural changes of the network under various stresses or shear conditions. We prepared hydrophobically modified polyacrylamide with N‐alkyl groups in the aqueous medium. The advantage of this method is that the production is pure without surfactants. These results suggest that the unique aqueous solution behavior of the copolymers is different from conventional hydrophobically associating acrylamide. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2465–2474, 2008
Preparation and properties of negative thermal expansion zirconium tungstate thin films deposited by radio frequency magnetron sputtering
Authors: Liu Hong‐Fei , Cheng Xiao‐Nong , Zhang Zhi‐Ping 
Published: October 2008

AbstractZirconium tungstate (ZrW2O8) thin films were deposited on quartz substrates by radio frequency magnetron sputtering followed by annealing at various temperatures. The effects of post‐deposition annealing temperature on the phase, morphology and negative thermal expansion properties of the ZrW2O8 thin films were investigated. X‐ray diffraction data confirmed that the as‐deposited ZrW2O8 films were amorphous, and crystalline ZrW2O8 films could be obtained at high annealing temperature. Trigonal ZrW2O8 films could be prepared at 740 °C and cubic ZrW2O8 films could be prepared at 1200 °C. The surface morphologies of the ZrW2O8 thin films were evaluated using scanning electron microscopy. The results indicated that amorphous ZrW2O8 films were uniform and dense, and the grain size of the crystalline ZrW2O8 films became larger with increasing annealing temperature. The resulting cubic ZrW2O8 films showed negative thermal expansion, the average value of thermal expansion coefficient being –8.18 × 10–6 K–1 in the temperature range 15–700 °C. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Broadband viscoelastic spectroscopy measurement of mechanical loss and modulus of polycrystalline BaTiO3 vs. temperature and frequency
Authors: Dong Liang , Stone Donald S. , Lakes Roderic S. 
Published: October 2008

AbstractCharacterization of pure polycrystalline BaTiO3 was carried out by means of Broadband Viscoelastic Spectroscopy (BVS) and Differential Scanning Calorimetry (DSC) above ambient temperature. A peak in mechanical loss has been observed near the Curie point 130 °C. The magnitude of the peak increases with thermal rate and decreases with frequency. Expressions for the peak magnitude have been derived based upon available models describing the first order phase transition. Mechanical anomalies were observed outside the vicinity of the phase transition. Transition temperature measured by BVS differed from that via DSC; the effect of stress on the ferroelastic transformation is a possible cause. Isothermal frequency scans revealed a hump in mechanical loss in the vicinity of the transition temperature below 1 Hz and a modulus decrease with decreasing frequency. Quasi‐isothermal studies revealed a significant softening in bulk modulus and a transient negative Poisson's ratio during the tetragonal‐to‐cubic phase transition. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prediction of auxetic phenomena in nanoporomaterials
Authors: Shilko S. V. , Petrokovets E. M. , Pleskachevsky Yu. M. 
Published: October 2008

AbstractPorous materials are efficient structures in respect to optimizing strength and stiffness for a given weight. A new means of improving the characteristics of the samples may be realized using abnormal deformation properties of auxetic porous materials having a negative Poisson's ratio ν. Auxetic porous materials are suitable for creating adaptive contact joints and for replacing damaged biotissue. It is known that the inverted or re‐entrant cell structure of porous auxetics may be obtained by isotropic permanent volumetric compression of conventional foam, resulting in microbuckling of the cell walls. There is interest in compression‐driven self‐assembly as a means to create auxetic porous structures on a nanoscale. To predict the deformation behaviour of porous materials under various types of loading, corresponding mathematical models should be developed. The possibility of compression‐driven self‐assembly of the auxetic nanostructures has been predicted. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Homological connectivity of random k‐dimensional complexes
Authors: Meshulam R. , Wallach N. 
Published: October 2008

AbstractLet Δn−1 denote the (n − 1)‐dimensional simplex. Let Y be a random k‐dimensional subcomplex of Δn−1 obtained by starting with the full (k − 1)‐dimensional skeleton of Δn−1 and then adding each k‐simplex independently with probability p. Let Hk−1(Y; R) denote the (k − 1)‐dimensional reduced homology group of Y with coefficients in a finite abelian group R. It is shown that for any fixed R and k ≥ 1 and for any function ω(n) that tends to infinity

© 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2009
On systematic scan for sampling H‐colorings of the path
Authors: Pedersen Kasper 
Published: October 2008

AbstractWe show that systematic scan for H‐colorings of the n‐vertex path mixes in O(log n) scans for any fixed H using block dynamics. For a restricted family of H we furthermore show that systematic scan mixes in O(log n) scans for any scan order. For completeness we show that a random update Markov chain mixes in O(nlog n) updates for any fixed H. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2009
Corrigendum: On fractional K‐factors of random graphs
Authors: Haber Simi , Krivelevich Michael 
Published: October 2008

AbstractWe regret that the article “On Fractional K‐Factors of Random Graphs,” which appeared in Random Structures and Algorithms (Haber and Krivelevich 30 (2007), 441–463), had an inaccuracy in Lemma 6.1. This in turn led to a misstatement in the description of a family of graphs demonstrating the tightness of the main result. In this short note, we fix this inaccuracy and also take the opportunity, kindly provided by the editors, to close a gap in the proofs of two of the technical lemmas. We like to point the readers to http://www.math.tau.ac.il/∼krivelev/papers.html, where a corrected version of the article appears. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008
A comparison of hospital performance with non‐ignorable missing covariates: An application to trauma care data
Authors: Kirkham Jamie J. 
Published: October 2008

AbstractTrauma is a term used in medicine for describing physical injury. The prospective evaluation of the care of injured patients aims to improve the management of a trauma system and acts as an ongoing audit of trauma care. One of the principal techniques used to evaluate the effectiveness of trauma care at different hospitals is through a comparative outcome analysis. In such an analysis, a national ‘league table’ can be compiled to determine which hospitals are better at managing trauma care. One of the problems with the conventional analysis is that key covariates for measuring physiological injury can often be missing. It is also hypothesized that this missingness is not missing at random (NMAR). We describe the methods used to assess the performance of hospitals in a trauma setting and implement the method of weights for generalized linear models to account for the missing covariate data, when we suspect the missing data mechanism is NMAR using a Monte Carlo EM algorithm. Through simulation work and application to the trauma data we demonstrate the affect the missing covariate data can have on the performance of hospitals and how the conclusions we draw from the analysis can differ. We highlight the differences in hospital performance and the ranking of hospitals. Copyright © 2008 John Wiley & Sons, Ltd.
Disintegration, recognition, and violence: A theoretical perspective
Authors: Heitmeyer Wilhelm , Anhut Reimund 
Published: October 2008

AbstractThe literature explaining deviance, criminality, or violence offers a broad spectrum of approaches in criminology and sociology. Mostly the theories focus on specific levels of explanation like the macrolevel (for example, strain theories) or the microlevel (for example, self‐control theory).This article presents a relatively new theoretical approach combining different levels and focusing on three dimensions associated with specific kinds of recognition: social‐structural, institutional, and socioemotional. The social‐structural dimension refers to access to the functional systems of society and the accompanying recognition of position, status, and so on. The institutional dimension concentrates on the opportunity to participate in public affairs with the aim of getting moral recognition. The socioemotional dimension emphasizes the quantity and quality of integration in and social support from families, friends, partners, and so on, which provide emotional recognition.The underlying idea is that lack of access, participation, and belonging causes a lack of recognition. When this happens, social and individual problems increase. Thus, deviant and violent behavior can be seen as one potential reaction to a lack of recognition and as a way to gain status and recognition in a different manner (for example, with a delinquent peer group or other gang).
Violence in street culture: Cross‐cultural comparison of youth groups and criminal gangs
Authors: Zdun Steffen 
Published: October 2008

AbstractViolence is a widespread phenomenon in juvenile street culture. But the questions of whether this relationship is a deterministic one, and if not, which are the contributing factors, are largely unanswered. This article focuses on the role of public space, starting with a comparison of the meaning of deviant behavior and crime in street culture in Brazil, Russia, and Germany. Focusing on street culture norms and their relevance for youth groups in everyday life, the author shows that there are worldwide similarities, and these are most likely to be seen in disadvantaged neighborhoods. The article deals not only with the question of how people act in conflicts but also focuses on a social order in which the reputation of men is based mainly on questions of masculinity, honor, and power expressed through aggressive behavior. The results are based on more than one hundred semistructured qualitative interviews with street culture youth, prison inmates, adult family members, social workers, police, and researchers that were conducted in recent years in the three countries.The study also describes a typology of conflict behavior among male street culture youth that helps in understanding why even juveniles who were socialized in the milieu of the street culture can reject violence and do not have to turn to violence in all conflicts. The article examines the similarities in the reasons for violence and fear of violence, as well as the differences in frequency and intensity between violent countries (such as Brazil and the Russian Federation) and less violent countries (for example, Germany).
Fears of violence among English young people: Disintegration theory and British social policy
Authors: Cockburn Tom 
Published: October 2008

AbstractYoung people are not only the perpetrators of violence; they are also the victims of violent acts. This leads to the question of how young people handle potential risk and how they can reduce the danger of becoming victims. The article stresses the topic of juvenile experience and fear of violence. Starting with a description of the nature of social disintegration in the north of England and the social consequences of social change at the beginning of the twenty‐first century, the author focuses on the experience of young people who are affected by changes in social policies, such as the governmental response to antisocial behavior, which is generally considered to be the cause of escalating youth crime. It is pointed out that young people's experience of social disintegration is more complex than generally considered. Based on one of the few qualitative studies in this research field, the study outlines the reasons for fear of violence by presenting comments by young people in two cities and three smaller towns in the north of England. In particular, it looks at the experience of young people in public spaces, the effect of excessive alcohol consumption, young people's fears around illegal drugs and violence, strategies young people use to remain safe, and factors that tend to reduce perceived safety. The authors question the wider societal view that young people are passive and innocent objects: this view has consequences regarding the drive to reduce and avoid violence (by adult society) but also can result in increased insecurity for young people. For this reason, the article also provides a new political approach regarding the communal context.
The role of social work in the context of social disintegration and violence
Authors: Möller Kurt 
Published: October 2008

AbstractViolence and the violence discourse are very similar from country to country: focus on youth, preponderance of males among perpetrators and victims, disproportionate involvement of migrants and indigenous people, greater prevalence with socioeconomic disadvantage and low education, and the impact of underlying factors such as political disintegration, exclusion from the consumer lifestyle, and inadequacies of social institutions. In social disintegration theory, the basic explanatory backdrop is the dynamic relationship of integration and disintegration between and within the different spheres: individual and functional system integration, integration into society, and integration into the community. (Relative) exclusion from work, consumption, and democratic processes combined with experience of socioemotional deficits seem to give a particularly strong boost to socially unacceptable forms of particularist integration and to favor collective and individual acceptance of violence. When subjects draw balances of personal recognition and of the achieved and achievable scope to organize their life, the latter orientations appear subjectively more likely to meet their expectations than socially (more) accepted modes of behavior.The central conclusion on social reactions to violence in general and professional social work in particular is that rather than relying on admonishment, punishment, or curative measures, or some combination of these, to combat violence, there is a need for wide‐ranging long‐term options for those acutely affected and at risk to have the long‐term scope to organize their own lives—to experience life control, recognized integration, and development of competences. Those who experience being the organizer of their own life have no need of violence as a form of self‐assertion.
Sensory‐motor polyneuropathy occurring in variant maple syrup urine disease
Authors: Harty S. , King M. D. , McCoy B. , Costigan D. , Treacy E. P. 
Published: October 2008

SummaryMaple syrup urine disease (MSUD; OMIM 248600) results from an inherited deficiency of the branched‐chain ketoacid dehydrogenase (BCKD) complex. Approximately 20% of patients with BCKD deficiency are non‐classic variants of MSUD with differing clinical severity. Outcomes for this cohort are generally favourable; episodes of metabolic decompensation do not appear to correlate with adverse events if acute management is promptly provided. A case of predominantly axonal sensory‐motor neuropathy following metabolic decompensation which persisted for a number of months is presented in an adolescent girl with variant (intermediate type) MSUD. EMG and nerve conduction studies suggested a pre‐existent asymptomatic chronic neuropathy, exacerbated by the acute decompensation. Peak leucine concentration at decompensation was 1083 μmol/L. The patient had laboratory signs of secondary mitochondrial respiratory chain dysfunction at presentation. She had been on a moderate dose of thiamine prior to decompensation; thiamine and pyridoxine blood concentrations were normal. This, to our knowledge, is the first report of a neuropathy presenting in a patient with a decompensation of variant MSUD. We propose that this presentation resembles the intermittent neuropathy observed in pyruvate dehydrogenase deficiency and may reflect secondary inhibition of pyruvate dehydrogenase activity by MSUD metabolites.
Detection of treatable neonatal liver disease by expanded newborn screening
Authors: Mackay R. J. , Bratkovic D. , Couper R. , Davidson G. P. , Fahy R. , Fletcher J. M. , Ranieri E. 
Published: October 2008

SummaryTwo neonates were identified at age 48 h by expanded newborn screening, with abnormal methionine and tyrosine concentrations, which were confirmed on repeat samples. Evidence of previously unsuspected liver disease was found at recall, and there was radiological and biochemical evidence of severe liver disease with hepatic synthetic failure. After inborn errors of metabolism (IEMs) were excluded, both were considered to have neonatal haemochromatosis, on the basis of raised ferritin, iron saturation, and very high α‐fetoprotein and confirmed by a mildly hyperferritinaemic sibling in the first case, and raised ferritin and iron saturation in the second. However, it was not feasible to obtain tissue confirmation as the requirement for early therapy precluded biopsy. The babies were treated with antioxidants and iron‐chelating agents, and the coagulopathy and hypoalbuminaemia were corrected. Both made a complete recovery and remain well after follow‐up. Newborn screening programmes could consider advising clinicians, when tyrosine and methionine values are elevated, that once IEMs are excluded liver disease from other causes must be sought. Neonatal haemochromatosis is an example of one such disease that is potentially treatable.
Mesoscale Dynamics
Authors: Orlanski Isidro 
Published: October 2008

Mesoscale meteorology is the study of atmospheric phenomena with typical spatial scales between 10 and 1000 kilometers. Examples of mesoscale phenomena include fronts, mesoconvective systems, thunderstorms, gap winds, downslope windstorms, and land‐sea breezes. Many of the weather phenomena that most directly affect human activity occur on the mesoscale.While researchers have been able to successfully predict large‐scale weather patterns since the 1950s, the prediction of smaller—or mesoscale—phenomena such as storms has proven more difficult. Why the lag in mesoscale prediction? The dynamics of weather phenomena on large scales can largely be described by considering just hydrostatic and geostrophic balance, allowing them to be described by highly simplified models.