bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thiocarbonylthio end group removal from RAFT‐synthesized polymers by a radical‐induced process
Authors: Chen Ming , Moad Graeme , Rizzardo Ezio 
Published: October 2009

AbstractThe removal of thiocarbonylthio end groups by radical‐addition‐fragmentation‐ coupling from polymers synthesized by RAFT polymerization has been studied. We found that a method, which involves heating the polymer with a large excess (20 molar equivalents) of azobis(isobutyronitrile) (AIBN), while successful with methacrylic polymers, is less effective with styrenic or acrylic polymers and provides only partial end group removal. This is attributed to the propagating radicals generated from the latter polymers being poor radical leaving groups relative to the cyanoisopropyl radical. Similar use of lauroyl peroxide (LPO) completely removes the thiocarbonylthio groups from styrenic or acrylic polymers but, even with LPO in large excess, produces a polymer with a bimodal molecular weight distribution. The formation of a peak of double molecular weight is indicative of the occurrence of self‐termination and ineffective radical trapping. We now report that by use of a combination of LPO (2 molar equivalents) and AIBN (20 molar equivalents) we are able to completely remove thiocarbonylthio end groups of styrenic or acrylic polymers and minimize the occurrence of self termination. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6704–6714, 2009
Higher α‐olefins carbonylation in aqueous media by Pd(II) catalysts modified with substituted diphosphine ligands: Aqueous polyketone latices with high solid contents and molecular weights
Authors: Sunjuk Mahmoud , Al‐Noaimi Mousa , Al‐Degs Yahya , Al‐Qirem Tareq , Lindner Ekkehard , Abu‐Surrah Adnan S. 
Published: October 2009

AbstractWater‐soluble palladium complexes cis‐[Pd(L)(OAc)2] (1–8) (L represents a diphosphine ligands of the general formula CH2(CH2PR2)2, where for a: R  (CH2)6OH; b–g: R  (CH2)nP(O)(OEt)2, n = 2–6 and n = 8; h: R  (CH2)3NH2) have been employed, after activation with a large excess of HBF4, for emulsion polymerization of alkenes (propene, butene, and their equimolar mixtures) with carbon monoxide. Aliphatic polyketone lattices with a high solid content (21%), high molecular weight (6.3 × 104 g mol−1), and narrow polydispersities (Mw/Mn ≈ 2) were isolated. The catalytic activity of the dicationic palladium (II) based catalysts, C1–C8 is highly dependent on the length of the alkyl chain of the ligand. Catalyst 3 proved to be highly active for propene/CO copolymers, whereas 6 is active for butene/CO and propene/CO‐butene/CO systems. The presence of methyl β‐cyclodextrin, as a phase‐transfer agent, and undecenoic acid, as an emulsifier, increase the molar mass and the stability of the polyketones and finally the activity of the catalyst. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6715–6725, 2009
Macroporous monolithic poly(4‐vinylbenzyl chloride) columns for organic synthesis facilitation by in situ polymerization of high internal phase emulsions
Authors: Kovačič Sebastijan , Krajnc Peter 
Published: October 2009

AbstractPolyHIPE materials are produced by polymerizing the continuous phase of emulsions where the internal phase volume fraction is higher than 74%. Columns of flow‐through supports for immobilized scavengers and reagents were prepared by polymerizing the continuous phase of high internal phase emulsions containing 4‐vinylbenzyl chloride and divinylbenzene. Emulsions were placed in containers and polymerized in situ. Highly porous (80% pore volume) monolithic columns with chloromethyl functionalities and crosslinked with divinylbenzene (6% or 40%) were obtained and functionalized by a flow‐through method, immobilizing tris(2‐aminoethyl)amine, diethanolamine, and 4‐bromophenylboronic acid. Columns with immobilized tris(2‐aminoethyl)amine were applied for the effective removal of acid chlorides from the solution pumped through the column. Flow properties (back pressure versus flow rate) were characterized for dichloromethane, N,N‐dimethylformamide and acetonitrile. High effectiveness of columns were demonstrated by an over 90% of acid chloride removal from the solution after a single pass‐flow of the solution through the column. The morphology of the column material was characterized by scanning electron microscopy and showed no damage of the material after the flow‐through utilization. Good permeative properties of the interconnected porous structure make polyHIPE columns good candidates for supports for reagents and catalysts. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6726–6734, 2009
A SAXS and swelling study of cured natural rubber/styrene–butadiene rubber blends
Authors: Salgueiro W. , Somoza A. , Marzocca A. J. , Torriani I. , Mansilla M. A. 
Published: October 2009

AbstractA small‐angle X‐ray scattering (SAXS) and swelling study of natural rubber and styrene–butadiene rubber blends (NR/SBR) is presented. To this aim, specimens of NR and SBR and blends with 75/25, 50/50, and 25/75 NR/SBR ratios (in phr) were prepared at a cure temperature of 433 K and the optimum cure time (t100). This time was obtained from rheometer torque curves. The system of cure used in the samples was sulfur/n‐t‐butyl‐2‐benzothiazole sulfenamide. From swelling tests of the cured samples, information about the molecular weight of the network chain between chemical crosslinks was obtained. For all cured compounds, in the Lorentz plots built from SAXS scattering curves, a maximum of the scattering vector q around 0.14 Å−1 was observed. However, the q position shows a linear‐like shift toward lower values when the SBR content in the SBR/NR blend increases. In pure NR or SBR the q values show a different tendency. The results obtained are discussed in terms of the existence of different levels of vulcanization for each single phase forming the blend and the existence of a third level of vulcanization located in the interfacial NR/SBR layer. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2320–2327, 2009
The effect of water content on the ultimate properties of rubbery nanocomposite gels
Authors: Haraguchi Kazutoshi , Li Huan‐Jun 
Published: October 2009

AbstractAn investigation was conducted into the effects of water content (R) on the ultimate tensile properties of nanocomposite hydrogels (NC gels) based on poly(N‐isopropylacrylamide)/clay networks. Rubbery NC gels with low clay contents (<NC10) exhibited unique changes in their stress–strain curves, depending on the R. At high R, where PNIPA chains are fully hydrated, NC gels retained their rubbery tensile properties, whereas they changed to exhibit plastic‐like deformations with decreasing R. Consequently, for a series of NC gels with different R, a failure envelope was obtained by connecting the rupture points in the stress–strain curves. Here, the counterclockwise movement was observed as either the R decreased or the strain rate increased. This seemed to be analogous to that of a conventional elastomer (e.g., SBR), although the mechanisms are different in the two cases. From the R and Cclay dependences of the ultimate properties, three critical values of R were defined, where R showed a maximum strain at break, a steep increase in initial modulus, and onset of brittle fracture. Compared with NC gels, OR gels (chemically crosslinked hydrogels) showed similar but very small changes in their stress–strain curves on altering R, whereas LR (viscous PNIPA solution) showed a monotonic decrease (increase) in εb (Ei) with decreasing R. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2328–2340, 2009
Vibrational spectroscopic investigation of poly(p‐phenylene sulfide)
Authors: Kumar Naresh , Shukla Sandeep Kumar , Tandon Poonam , Gupta Vishwambhar Dayal 
Published: October 2009

AbstractPoly(p‐phenylene sulfide) (PPS) is an important polymer of engineering interest particularly useful in the electronics and automotive industries. Normal mode analysis including phonon dispersion has been performed to understand completely the vibrational spectra of this polymer. Various characteristic features of the dispersion curves have been reported. Crossing/Repulsion between various pairs of modes at certain phase values have been explained as arising due to internal symmetry in the energy momentum space. The heat capacity is calculated as a function of temperature via density‐of‐states in the range 220–360 K. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2353–2367, 2009
Strongly segregated cubic microdomain morphology consistent with the double gyroid phase in high molecular weight diblock copolymers of polystyrene and poly(dimethylsiloxane)
Authors: Politakos Nikolaos , Ntoukas Eleftherios , Avgeropoulos Apostolos , Krikorian Vahik , Pate Brian D. , Thomas Edwin L. , Hill Randal M. 
Published: October 2009

AbstractWe report the observation of a cubic phase consistent with the double gyroid structure in strongly segregated diblock copolymers of PS‐b‐PDMS over a volume fraction (φPDMS) range of ∼0.39 to 0.45. The samples have respective molecular weights of 127 kg/mol and 73 kg/mol and degree of segregation Nχ equal to 187 and 106, respectively, at annealing temperature of 130 °C. It is important to highlight that two out of the total four samples investigated, exhibited hexagonally close packed cylindrical domains of PDMS and alternating lamellae at φPDMS = 0.39 and 0.45, respectively, indicating the possible narrow range of the DG morphology for the specific diblock copolymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2419–2427, 2009
Psychosocial adjustment of siblings of children with cancer: a systematic review
Authors: Alderfer Melissa A. , Long Kristin A. , Lown E. Anne , Marsland Anna L. , Ostrowski Nancy L. , Hock Janet M. , Ewing Linda J. 
Published: October 2009

AbstractObjectives: To promote a broader understanding of the psychosocial impact of childhood cancer on siblings, a systematic review was undertaken. Directions for future research are proposed and clinical strategies are suggested for addressing the needs of these children.Methods: Searches of Medline, PsycINFO and CINAHL revealed 65 relevant qualitative, quantitative, or mixed methods' papers published between 1997 and 2008. These papers were rated for scientific merit and findings were extracted for summary.Results: Siblings of children with cancer do not experience elevated mean rates of psychiatric disorders, but a significant subset experiences post‐traumatic stress symptoms, negative emotional reactions (e.g. shock, fear, worry, sadness, helplessness, anger, and guilt), and poor quality of life in emotional, family, and social domains. In general, distress is greater closer to time of diagnosis. School difficulties are also evident within 2 years of diagnosis. Qualitative studies reveal family‐level themes such as loss of attention and status as well as positive outcomes including increased sibling maturity and empathy.Conclusions: Research regarding siblings of children with cancer continues to be methodologically limited. The conclusions of qualitative and quantitative studies differ considerably. We propose a research agenda to propel this field forward including greater attention to alterations in normative development (as opposed to psychiatric conditions), development of more appropriate quantitative measures, examination of potential moderators of adaptation, and use of prospective longitudinal designs. Siblings of children with cancer are a psychosocially at‐risk group and should be provided with appropriate supportive services. Copyright © 2009 John Wiley & Sons, Ltd.
Sexual functioning in young adult survivors of childhood cancer
Authors: Zebrack Brad J. , Foley Sallie , Wittmann Daniela , Leonard Marcia 
Published: October 2009

AbstractBackground: Studies of sexuality or sexual behavior in childhood cancer survivors tend to examine relationships or achievement of developmental milestones but not physiological response to cancer or treatment. The purpose of this study is to (1) identify prevalence and risk factors for sexual dysfunction in childhood cancer survivors, and (2) examine the extent to which sexual dysfunction may be associated with health‐related quality of life (HRQOL) and psychosocial outcomes.Methods: Five hundred ninety‐nine survivors age 18–39 years completed standardized measures of sexual functioning, HRQOL, psychological distress and life satisfaction. Descriptive statistics assessed prevalence of sexual symptoms. Bivariate analyses identified correlates of sexual symptoms and examined associations between symptoms and HRQOL/psychosocial outcomes.Results: Most survivors appear to be doing well, although 52% of female survivors and 32% of male survivors reported at least ‘a little of a problem' in one or more areas of sexual functioning. Mean symptom score for females was more than twice that of males. Sexual symptoms were associated with reporting health problems. Significant associations between sexual functioning and HRQOL outcomes were observed, with gender differences in strengths of association suggesting that males find sexual symptoms more distressing than do females.Conclusions: While most survivors appear to be doing well in this important life domain, some young adult survivors report sexual concerns. While female survivors may report more sexual symptoms than male survivors, males may experience more distress associated with sexual difficulties. Better‐specified measures of sexual function, behavior and outcomes are needed for this young adult population. Copyright © 2009 John Wiley & Sons, Ltd.
Looking past the obvious: experiences of altered masculinity in penile cancer
Authors: Bullen Kathryn , Edwards Stephen , Marke Victoria , Matthews Sarah 
Published: October 2009

AbstractObjectives: Penile cancer, although statistically rare in Western countries (1:100 000 per year), results in considerable physical and psychological morbidity. The treatment of choice for penile cancer is either partial or total amputation of the penis. Metastatic spread into the surrounding lymphatic system may require additional surgery. To date, little is known of the lived experiences of men with penile cancer regarding the impact of the disease and its treatment on dimensions of masculinity.Methods: A small‐scale qualitative study using Interpretative Phenomenological Analysis (IPA). IPA aims at exploring the experience of life events and the meaning and implications for the person living through them. A purposive sample of men with penile cancer who were within a minimum of 18 months post‐surgery were recruited via a specialist urology clinic (n = 9). Participants were interviewed by a male researcher using a pre‐agreed semi‐structured interview schedule; interviews were audio recorded for transcription with detailed analyses of main and sub‐themes conducted independently by three researchers. To maintain analytical rigour, constant comparisons of main and sub‐themes were made between the individual transcripts and across the emergent themes within the research group.Results: Central themes were (1) grappling with reality; (2) learning to cope and (3) changes to self.Conclusions: That men should have an altered sense of masculine identity following penile cancer surgery is not unexpected. However, the ways in which altered masculinity manifested itself were both subtle and insidious. The results have implications for clinical practice and demonstrated the need for further research. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of Electrode Protrusion Length, Pre‐Existing Bubbles, Solution Conductivity and Temperature, on Liquid Phase Pulsed Electrical Discharge
Authors: Shih Kai‐Yuan , Locke Bruce R. 
Published: October 2009

AbstractThe effects of high voltage electrode needle protrusion length and the presence of low density pre‐existing bubbles on liquid phase pulsed electrical discharge were investigated. Liquid phase pulsed corona discharge was operated with two different protrusion length needle electrodes (short – 2 mm and long – 20 mm) with different bulk solution conductivities (5 µS · cm−1and 150 µS · cm−1) at room temperature (25 °C) and near boiling (95 °C). Chemical reactions formed in the discharge were also investigated by measuring the generation rates of hydrogen (H2), oxygen (O2) and hydrogen peroxide (H2O2).magnified image
Potential enhancement of degradation of the nematicides aldicarb, oxamyl and fosthiazate in UK agricultural soils through repeated applications
Authors: Osborn Rachel K , Edwards Simon G , Wilcox Andrew , Haydock Patrick PJ 
Published: October 2009

AbstractBACKGROUND: The potential for enhanced degradation of the carbamoyloxime nematicides aldicarb and oxamyl and the organophosphate fosthiazate was investigated in 35 UK agricultural soils. Under laboratory conditions, soil samples received three successive applications of nematicide at 25 day intervals.RESULTS: The second and third applications of aldicarb were degraded at a faster rate than the first application in six of the 15 aldicarb‐treated soils, and a further three soils demonstrated rapid degradation of all three applications. High organic matter content and low pH had an inhibitory effect on the rate of aldicarb degradation. Rapid degradation was observed in nine out of the ten soils treated with oxamyl. In contrast, none of the fosthiazate‐treated soils demonstrated enhanced degradation.CONCLUSION: The potential for enhanced degradation of aldicarb and oxamyl was demonstrated in nine out of 15 and nine out of ten soils respectively that had previously been treated with these active substances. Degradation of fosthiazate occurred at a much slower rate, with no evidence of enhanced degradation. Fosthiazate may provide a useful alternative in cases where the efficacy of aldicarb and oxamyl has been reduced as a result of enhanced degradation. Copyright © 2009 Society of Chemical Industry
Deep defect level spectra in the neutron irradiated Si ionizing radiation detectors
Authors: Kažukauskas Vaidotas , Kalendra Vidmantas , Vainorius Neimantas , Pranaitis Mindaugas , Vaitkus Juozas Vidmantis 
Published: October 2009

AbstractIn the framework of WODEAN project of CERN‐RD50 collaboration the photoconductivity spectra of p+‐n‐n+ Si detectors were investigated depending on irradiation by high energy neutrons. The samples were irradiated by neutrons to the fluencies 1×1013 –1×1016 cm2. The extrinsic photoconductivity spectra indicated that upon irradiation deep levels (DL) below the middle of the band gap were created. Their activation energies were in the ranges of 0.49‐0.52 eV, 0.77‐0.81 eV, 0.88‐0.91 eV, and 1.02‐1.11 eV. The effective concentrations of these levels were depending on the fluencies and on the isochronal thermal treatments at low temperatures. The changes of DL population induced by annealing have been compared with the steady state lifetimes and photoconductivity decay constants. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SiON as a barrier layer for depositing an Al2O3 thin film on Si for gate applications
Authors: Zhen Congmian , He Gang , Wang Xiaoliang , Shimogaki Yukihiro 
Published: October 2009

AbstractOxynitridization of an Si wafer was conducted by rapid thermal annealing in NH3 and O2. The refractive index of the SiON barrier layer formed at 1000 °C for 0.5 min was relatively high, about 1.96 at 589 nm, showing that the oxynitridized layer formed was compact. An Al2O3 film was then deposited on the SiON layer by metalorganic chemical vapor deposition using new chemical vapor deposition chemistry. X‐ray photoelectron spectroscopy showed that the SiON barrier layer effectively prevents the formation of a layer of SiO2 or aluminum silicate at the interface between the Al2O3 layer and the Si wafer. Electrical measurements confirmed that few mobile charges were found to exist in the Al2O3 film. The higher Al2O3 dielectric constant and the lower equivalent oxide thickness were achieved when the sample was subjected to oxynitridization. A reduced flat band voltage shows that the SiON layer also decreases the interface trap charges and improves the interface quality. The leakage current density of the sample with oxynitridization obviously reduced with JA = 2.54 × 10−8 A/cm2 at a voltage Vg = +1.00 V. Copyright © 2009 John Wiley & Sons, Ltd.
Early exposure to haloperidol or olanzapine induces long‐term alterations of dendritic form
Authors: Frost Douglas O. , Page Stephanie Cerceo , Carroll Cathy , Kolb Bryan 
Published: October 2009

AbstractExposure of the developing brain to a wide variety of drugs of abuse (e.g., stimulants, opioids, ethanol, etc.) can induce life‐long changes in behavior and neural circuitry. However, the long‐term effects of exposure to therapeutic, psychotropic drugs have only recently begun to be appreciated. Antipsychotic drugs are little studied in this regard. Here, we quantitatively analyzed dendritic architecture in adult mice treated with paradigmatic typical‐ (haloperidol) or atypical (olanzapine) antipsychotic drugs at developmental stages corresponding to fetal or fetal plus early childhood stages in humans. In layer 3 pyramidal cells of the medial and orbital prefrontal cortices and the parietal cortex and in spiny neurons of the core of the nucleus accumbens, both drugs induced significant changes (predominantly reductions) in the amount and complexity of dendritic arbor and the density of dendritic spines. The drug‐induced plasticity of dendritic architecture suggests changes in patterns of neuronal connectivity in multiple brain regions that are likely to be functionally significant. Synapse 64: 191–199, 2010. © 2009 Wiley‐Liss, Inc.
Muscarinic receptor blockade in the ventral tegmental area attenuates cocaine enhancement of laterodorsal tegmentum stimulation‐evoked accumbens dopamine efflux in the mouse
Authors: Lester Deranda B. , Miller Anthony D. , Blaha Charles D. 
Published: October 2009

AbstractThe reinforcing properties of cocaine have been related to increased extracellular concentrations of dopamine in the nucleus accumbens (NAc). M5 muscarinic acetylcholine receptors (mAChRs) on dopamine cells in the ventral tegmental area (VTA) facilitate mesoaccumbens dopamine transmission and are critically involved in mediating natural and drug reinforcement. We investigated the effects of pharmacological blockade of mAChRs in the VTA on cocaine's ability to enhance electrically evoked NAc dopamine efflux. Using fixed potential amperometry together with carbon fiber recording microelectrodes positioned in the NAc core, we quantified dopamine oxidation currents (dopamine efflux) evoked by brief stimulation (15 monophasic pulses at 50 Hz every 30 s) of the laterodorsal tegmentum (LDT) in urethane (1.5 g/kg, i.p.) anesthetized mice. Compared to predrug baseline responses, cocaine (5 or 10 mg/kg, i.p.) dose‐dependently enhanced LDT stimulation‐evoked NAc dopamine efflux, whereas the nonsubtype selective mAChR antagonist scopolamine (10 μg/0.5 μl) microinfused into the VTA diminished LDT‐evoked NAc dopamine efflux. Preinfusion of scopolamine into the VTA diminished the facilitatory actions of cocaine on LDT stimulation‐evoked NAc dopamine efflux, and when infused at the peak effect of cocaine attenuated LDT‐evoked dopamine efflux to below predrug baseline levels. These findings suggest that LDT cholinergic inputs to dopamine neurons in the VTA, via activation of mAChRs (probably of the M5 subtype), are involved in modulating the facilitatory effects of cocaine on NAc dopamine neurotransmission. They also suggest that the development of antagonists aimed at selectively disrupting M5 receptor function may be valuable in reducing abuse liability of psychostimulants. Synapse 64:216–223, 2010. © 2009 Wiley‐Liss, Inc.