bluuebunny/crossref_metadata_2025 huggingface dataset:
Pyridine‐Modified Polymer as a Non‐Covalent Compatibilizer for Multi‐Walled CNT/Poly[ethylene‐co‐(methacrylic acid)] Composites Fabricated by Direct Melt Mixing
Authors: Cohen Eyal , Ophir Amos , Kenig Shmuel , Barry Carol , Mead Joey
Published: August 2012

Multi‐wall CNT/poly[ethylene‐co‐(methacrylic acid)] composites were prepared by melt mixing. To improve dispersion and promote polymer/nanotube interactions, a novel non‐covalent compatibilizer is synthesized by reacting the polymer with 4‐(aminomethyl)pyridine. The composite based on the pristine polymer shows electrical and rheological percolation thresholds at nanotube loadings of 1.85 and 1.4 wt%, respectively. When 5 wt% of the pyridine‐modified compatibilizer is added, the corresponding values are reduced to 1.44 and 0.8 wt%, respectively. The electrical resistivity decreases even further as 10 wt% of the novel dispersing agent is used. Microscopy and Raman spectroscopy confirm the improved dispersion and π‐interactions established during melt mixing.

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Glucose‐Regulated Insulin Release from Acid‐Disintegrable Microgels Covalently Immobilized with Glucose Oxidase and Catalase
Authors: Wu Yonghao , Hu Huamin , Hu Jinming , Liu Shiyong
Published: August 2012

The fabrication of a novel type of positively charged acid‐disintegrable microgel loaded with insulin by electrostatic interactions and covalently immobilized with glucose oxidase (GOx) and catalase by inverse emulsion polymerization is reported, aiming for glucose‐regulated insulin release by utilizing GOx/catalase cascade enzymatic reactions to trigger local pH decrease and acid‐cleavage of crosslinking moieties. At the same time, a local pH decrease within the microgels also leads to the diminishment of net surface negative charges of encapsulated insulin. The above two factors both synergistically contribute to the prominently enhanced insulin release at high glucose levels (∼10–20 mM) compared to that in the absence of glucose.
High‐Resolution ultrasound of the pudendal nerve: Normal anatomy
Authors: Tagliafico Alberto , Perez Maribel Miguel , Martinoli Carlo
Published: July 2012

Introduction: In this study we aimed to determine whether high‐resolution ultrasound (US) can identify the pudendal nerve and its terminal branches. We also attempted to identify the best approach for visualizing these structures. Methods: Normal anatomy of the pudendal nerve was evaluated in 3 cadavers and 20 healthy volunteers proximally at the level of the ischial spine and distally with low‐frequency (2–5‐MHZ) and high‐frequency (12–7‐MHZ and 17–5‐MHZ) transducers. Two musculoskeletal radiologists performed the examinations and evaluations. Volunteers were placed in 3 different positions, which allowed different approaches (posterior, medial, and anterior transperineal). A 0–3 scale was used to assess nerve visibility. Results: Visualization of the pudendal nerve at the ischial spine was best when using a medial approach (P < 0.004); the terminal branches were seen best with the anterior approach (P < 0.002). Conclusion: High‐resolution ultrasound (US) can identify the pudendal nerve and its terminal branches. Muscle Nerve 47:403‐408, 2013
Electrophysiological and ultrasonographic findings in ulnar neuropathy with martin‐gruber anastomosis
Authors: Cho Nam Soon , Kim Dong Hwee , Kim Min Young , Park Byung Kyu
Published: August 2012

Introduction

It is important to understand the presence of Martin‐Gruber anastomosis in patients with complete ulnar neuropathy at the elbow. Case Report: We describe a patient with complete ulnar neuropathy at the elbow and Martin‐Gruber anastomosis in the forearm, mimicking incomplete ulnar neuropathy with complete conduction block in the forearm segment. Ultrasonography of the ulnar nerve around the elbow demonstrated severe swelling of the ulnar nerve, which was compatible with severe ulnar neuropathy at the elbow. Conclusions: This case report demonstrates that combination of ultrasonography with electrophysiological studies can provide more detailed information about the changes of nerve structures and lesion sites. Muscle Nerve, 2013
Synergistic effects of polyethylene glycol and ammonium polyphosphate on intumescent flame‐retardant polypropylene
Authors: Li Xiuyun , Yan Tairong , Hu Xiaoping , Wang Ke , Fu Qiang
Published: August 2012

A novel flame‐retardant system of isotactic polypropylene (iPP) is prepared using polyethylene glycol (PEG) and ammonium polyphosphate (APP). The flammability of iPP/PEG/APP composites containing 20 wt% APP improves with the increase of PEG concentration in the range of 3–15 wt%. The limit oxygen index (LOI) of iPP/PEG/APP composites reaches up to 30% with 15 wt% PEG concentration in the composites. At the same time, the mechanical properties of iPP/PEG/APP composites demonstrate that PEG can enhance toughness of iPP/APP composites. The results of cone calorimetry prove the synergistic effects of PEG and APP on intumescent flame‐retardant iPP, and those of the thermogravimetric analysis(TGA) reveal that iPP/PEG/APP samples decompose faster than iPP/APP composites. Investigated by scanning electronic microscopy (SEM), the morphology and structures of residues generated during LOI tests confirm the formation of effective char layer, and that the improvement of the flame retardancy and the impact strength of the composites are thanks to the presence of PEG. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Isothermal crystallization kinetics and melting behaviors of poly(butylene terephthalate) and poly(butylene terephthalate‐co‐fumarate) copolymer
Authors: Xiao Xiaoling , Zeng Zuoxiang , Xue Weilan , Kong Qingjuan , Zhu Wanyu
Published: July 2012

The isothermal crystallization kinetics and melting behaviors after isothermal crystallization of poly(butylene terephthalate) (PBT) and poly(butylene terephthalate‐co‐fumarate) (PBTF) containing 95/5, 90/10, and 80/20 molar ratios of terephthalic acid/fumaric acid were investigated by differential scanning calorimetry. The equilibrium melting temperatures of these polymers were estimated by Hoffman–Weeks equation. So far as the crystallization kinetics was concerned, the Avrami equation was applied and the values of the exponent n for all these polymers are in the range of 2.50–2.96, indicating that the addition of fumarate does not affect the geometric dimension of PBT crystal growth. Crystallization activation energy (ΔE) and nucleation constant (Kg) of PBTF copolymers are higher than that of PBT homopolymer, suggesting that the introduction of fumarate hinders the crystallization of PBT in PBTF. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Studies of new oligomer–metal complexes and their antibacterial activities
Authors: Azarudeen Raja S , Burkanudeen Abdul R
Published: August 2012

A new oligomeric ligand was synthesized from anthranilic acid and 2‐aminopyridine with formaldehyde using a condensation technique in the presence of acid medium. Oligomer–metal complexes were prepared involving transition metal ions Cu(II), Mn(II) and Zn(II) using the synthesized oligomer as ligand. The oligomeric ligand and its metal complexes were characterized using various spectral techniques such as Fourier transform infrared, electronic, electron spin resonance, 1H NMR and 13C NMR. Gel permeation chromatography was used to determine number‐, weight‐ and size‐average molecular weights of the oligomeric ligand. The surface characteristics and nature of the oligomeric ligand and its metal complexes were examined using scanning electron microscopy and X‐ray diffraction analysis. The thermal properties and degradation behaviour of the oligomeric ligand and its complexes were investigated using thermogravimetric analysis. Kinetic and thermodynamic studies of the ligand and its metal complexes were carried out using Freeman–Carroll (FC) and Sharp–Wentworth (SW) methods. From the thermogravimetric data, kinetic and thermodynamic parameters such as activation energy, order of reaction, entropy change, apparent entropy, frequency factor and free energy change were calculated. The activation energy was further calculated from the Phadnis‐Deshpande (PD) method and the degradation mechanism for the thermal decomposition reaction is proposed. The activation energy calculated from the FC and SW methods was in good agreement with that calculated from the PD method. The oligomeric ligand and its metal complexes were screened for antibacterial activity. It was found that the synthesized compounds were potent antibacterial agents. © 2012 Society of Chemical Industry
Multi‐walled carbon nanotubes as unexpected accelerators of chemical reactions
Authors: Courbaron Gilbert Anne‐Claude , Billon Laurent , El Bounia Noureddine , Derail Christophe
Published: August 2012

The influence of carbon nanotubes on various chemical reactions has been examined. These reactions include epoxy crosslinking, in situ polymerization of copolymers in the presence of carbon nanotubes and thermal degradation of a thermoplastic matrix. The various characterizations were based on different types of analyses, including differential scanning calorimetry, proton nuclear magnetic resonance, size exclusion chromatography and thermogravimetric analysis. In each case, we show that the presence of multi‐walled carbon nanotubes accelerates the process. © 2012 Society of Chemical Industry
Kinetics and mechanisms in flow systems: reduction of SO2 on carbons
Authors: Humeres Eduardo , Moreira Regina de F. P. M.
Published: July 2012

Surface‐science studies of some reactions have allowed postulating the mechanisms using a variety of techniques. The surface chemistry of Group IV elements has been particularly studied recently because Si, Ge, and C are semiconductors, and the surface organic chemistry to functionalize these elements has seen immense progress in recent years. In this review article we describe the methodology used to study the mechanism of a solid–gas reaction, the reduction of SO2 on carbons, and the necessary conditions that allowed the measurement of the solid conversion and product distribution when the kinetics was chemically controlled and the reaction had reached the steady state. The reaction was first‐order with respect to SO2 and with respect to carbon and the stoichiometry was determined from the product distribution. The reaction proceeds through two thermally stable reaction intermediates bound to the surface, a six‐membered ring 1,3,2‐dioxathiolane and a five‐membered ring 1,2‐oxathietene 2‐oxide or γ‐sultine, both species being in equilibrium. The reaction was shown to be reversible. The primary product is an episulfide that, after a series of consecutive reactions of atomic sulfur, is able to free sulfur. The reactivity of the intermediates and the episulfide was studied for several reactions and consistent mechanisms were postulated from the X‐ray photoelectron spectroscopy and solid state nuclear magnetic resonance spectra. Aminolysis and the reaction with alkyl halides resulted on the insertion of the alkyl moiety in the episulfide primary product, while the thiolysis and photolytic alcoholysis resulted in the insertion of the alkyl moiety in the oxidized intermediates. Copyright © 2012 John Wiley & Sons, Ltd.
Study on the scope of tert‐amino effect: new extensions of type 2 reactions to bridged biaryls
Authors: Bottino Paola , Dunkel Petra , Schlich Michele , Galavotti Lorenzo , Deme Ruth , Regdon Géza , Bényei Attila , Pintye‐Hódi Klára , Ronsisvalle Giuseppe , Mátyus Péter
Published: August 2012

Thermal isomerization of aminomethyl‐ or oxygen‐bridged biphenyl systems possessing dicyanovinyl and sec‐amino groups in ortho‐ and ortho′‐positions was investigated. Both systems underwent cyclization via tert‐amino effect. Thus, 2‐(2‐{[2‐(sec‐amino)benzyl]‐N‐methylamino}benzylidene)malononitriles gave tetrahydroquinolines, whereas a 2‐[2‐(sec‐amino)phenoxy]benzylidenemalononitrile isomerized to dibenzoxazonine derivative. The ring closure reaction was studied by differential scanning calorimetry measurements. Copyright © 2012 John Wiley & Sons, Ltd.
Polyelectrolyte complex nanoparticles from chitosan and poly(acrylic acid) and Polystyrene‐block‐poly(acrylic acid)
Authors: Rolland Julien , Guillet Pierre , Schumers Jean‐Marc , Duhem Nicolas , Préat Véronique , Gohy Jean‐François
Published: July 2012

Interpolymer polyelectrolyte complexes of chitosan (CS) with poly(acrylic acid) homopolymers and polystyrene‐block‐poly(acrylic acid) diblock copolymers were prepared and characterized. The influence of the positive/negative charge balance (charge ratio), pH, and ionic strength were thoroughly studied by dynamic light scattering. The existence of a strong polyelectrolyte effect was also highlighted in this study. Domains of stability, in which nanoparticle sizes are smaller than 100 and 200 nm for complexes of CS with the homopolymer and copolymer, respectively, were identified and confirmed by scanning electron microscopy and atomic force microscopy. The charged nature of the surface of the nanoparticles was evidenced by Zeta potential measurements. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Thermoresponsive graphene oxide‐PNIPAM nanocomposites with controllable grafting polymer chains via moderate in situ SET–LRP
Authors: Deng Yan , Zhang Jin Zhong , Li Yongjun , Hu Jianhua , Yang Dong , Huang Xiaoyu
Published: August 2012

In this study, we report a mild and efficient strategy for growing thermosensitive polymers directly from the surface of exfoliated graphene oxide (GO). Exfoliated GO sheets were sequentially subject to the epoxide ring‐opening reaction with tris(hydroxymethyl) aminomethane (TRIS) to increase the amount of reactive sites, the esterification with 2‐bromo‐2‐methylpropionyl bromide to introduce the Br‐containing initiating groups, and the surface‐initiated single electron transfer–living radical polymerization of N‐isopropylacrylamide (NIPAM) to tune the molecular weights of grafted polymers. All these reactions were performed at ambient temperature without losing any other oxygen‐containing functionality on GO. The resulting TRIS‐GO‐PNIPAM nanocomposites still maintain the separated single layers in dispersion, and the dispersibilities in organic solvents are significantly improved. Meanwhile, the aqueous dispersion of TRIS‐GO‐PNIPAM shows reversible temperature switching self‐assembly and disassembly behavior at about 40°C. Such smart graphene‐based hybrid materials are promising for applications in nanoelectronics, sensors, and microfluidic switches. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Optically active core/shell nanoparticles prepared using self‐assembled polymer micelle as reactive nanoreactor
Authors: Zhang Haiyang , Ding Lei , Chen Yu , Yang Wantai , Deng Jianping
Published: August 2012

This article reports on optically active core/shell nanoparticles constituted by chiral helical polymers and prepared by a novel approach: using self‐assembled polymer micelles as reactive nanoreactors. Such core/shell nanoparticles were composed of optically active helical‐substituted polyacetylene as the core and thermosensitive poly(N‐isopropylacrylamide) as the shell. The synthetic procedure is divided into three major steps: (1) synthesis of amphiphilic diblock copolymer bearing polymerizable C[tbond]C bonds via atom transfer radical polymerization, followed by (2) self‐assembly of the diblock copolymer to form polymer micelles; and (3) catalytic emulsion polymerization of substituted acetylene monomer conducted using the polymer micelles as reactive nanoreactors leading to the core/shell nanoparticles. The core/shell nanoparticles simultaneously exhibited remarkable optical activity and thermosensitivity. The facile, versatile synthesis methodology opens new approach toward preparing novel multifunctional core/shell nanoparticles.© 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Aggregation behavior of organic‐soluble semi‐aromatic polyimides in N‐methylpyrrolidone systems
Authors: Ogata Yoichi , Fujita Kenji , Nakanishi Megumi , Okaniwa Motoki , Sekiguchi Manabu
Published: July 2012

Aggregation behavior of the organic‐soluble semi‐aromatic polyimides, whose degrees of imidization range from 69 to 96%, obtained using 4,4′‐oxydianiline, 4,4′‐diamino‐3,3′dihydroxybiphenyl, and bicyclo[2.2.2]‐oct‐7‐ene‐2,3,5,6‐tetracarboxylic dianhydride (BCDA) in N‐methylpyrrolidone (NMP), NMP/cyclohexanone, and NMP/γ‐butyrolactone (BCDA‐based polyimides) were studied by static light scattering (SLS) and dynamic light scattering (DLS). The DLS analyses for the multirelaxation modes demonstrated the specific character unlike flexible polymers that the single BCDA‐based polyimide chains first associate with each other to form small clusters in the dilute region, and then expand to large aggregates by the entanglements between the small clusters with an increasing concentration into the semi‐dilute region. Given the semi‐aromatic structure of BCDA‐based polyimides weakening the charge transfer (CT) interaction between the diamine and the dianhydride unit, it is concluded that the unique aggregation behavior of BCDA‐based polyimides is dominated by the balance between the driving force for the “organic solubility” given by both the increase in bulkiness and the decrease in the CT interaction, and that for the “organic insolubility” derived from both the hydrogen‐bonded interaction of the phenolic hydroxyl groups and the π–π interaction of the phenyl rings. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Stereochemical heterogeneity of biodegradable poly(L‐lactide) homopolymer as revealed by temperature rising elution fractionation and successive self‐nucleation/annealing thermal fractionation
Authors: Luo Jun , Huo Fei , Lin Hui , Lin Zhouli , Chen Zhengjian , Yuan Fang , Jiang Hongliang , Wang Hongjun , Tu Kehua , Liu Dingrong , Tan Songwei , Wang Li‐Qun
Published: July 2012

Commercial poly(L‐lactide) is typically heterogeneous in chain structure due to the existence of a small amount of D‐lactyl units that are produced by the racemization reactions during the synthesis. In this article, the stereochemical heterogeneity of two commercial poly(L‐lactide) was investigated with temperature rising elution fractionation (TREF) and successive self‐nucleation/annealing (SSA) thermal fractionation. For both samples, three fractions were collected and characterized with rotatory power analysis and DSC. The fractions show distinct optical purity and DSC results, which reflect the structure differences among them directly. After SSA treatment, the observation of multiple endotherms for each physically separated fraction confirms the fractionated sample contains a heterogeneous intermolecular and intramolecular distribution of defects. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Preparation, characterization, and properties of novel biodegradable aliphatic–aromatic copolyester nanohybrids with polyhedral oligomeric silsesquioxanes moieties
Authors: Wang Bing‐Tao , Zhang Yan , Zhang Ping , Gao De , Fang Zheng‐Ping
Published: August 2012

Biodegradable aliphatic–aromatic copolyester nanohybrids, with polyhedral oligomeric silsesquioxane (POSS) moieties tethered between poly(lactic acid) (PLA) and poly(butylene terephthalate) segments, is designed and prepared. First, (bis(2‐hydroxyethyl) dipropionate POSS, BH‐POSS) is synthesized under mild conditions, then in situ polycondensation is carried out in the presence of terephthalic acid, PLA oligomer, 1,4‐butanediol, and BH‐POSS.1 H‐NMR and Fourier transfer infrared spectroscopy confirm that Michael addition reaction of amino‐POSS and hydroxyethyl acrylate takes place efficiently and forms BH‐POSS in high yield at room temperature. Owing to similar functional groups, BH‐POSS could be easily incorporated into the macromolecular chains and obtain final copolyester nanohybrids. Moreover, X‐ray diffractometry and transmission electron microscopy observations demonstrate that POSS moieties occur self‐assembly behaviors and form nanoaggregates with the diameter of 50–100 nm. The thermal stability and mechanical properties of the copolyester nanohybrids containing BH‐POSS are substantially improved. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Microstructure, electrical, and electromagnetic interference shielding properties of carbon nanotube/acrylonitrile–butadiene–styrene nanocomposites
Authors: Al‐Saleh Mohammed H. , Sundararaj Uttandaraman
Published: August 2012

Processing, electrical, and electromagnetic interference (EMI) shielding behaviors of carbon nanotube (CNT)/acrylonitrile–butadiene–styrene (ABS) nanocomposites were studied as function of CNT concentration. The nanocomposites were prepared by melt mixing followed by compression molding. The selective and good level of dispersion of CNT in the styrene–acrylonitrile section of the ABS polymer was found to create conductive networks in the ABS matrix at a nanofiller loading of 0.75 wt %. At this nanofiller loading, the nanocomposite electrical conductivity was 10−5 S/m. This conductivity makes the nanocomposite suitable for electrostatic discharge protection applications. The EMI shielding effectiveness of the nanocomposites increased with the increase in nanofiller concentration. In the 100–1500 MHz frequency range, 1.1 mm thick plates made of ABS nanocomposite filled with 5 wt % CNT exhibit an EMI shielding effectiveness of 24 dB. At this shielding level, the nanocomposite is suitable for a broad range of applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Microwave experiments using open chaotic cavities in the realm of the effective Hamiltonian formalism
Authors: Kuhl U. , Legrand O. , Mortessagne F.
Published: July 2012

The description of open quantum system successfully uses the concept of the effective Hamiltonian, which takes into account the coupling to the environment. The concept can be extended to classical waves. Experimentally, classical waves are very convenient as they allow to control boundaries, coupling and absorption. We combine here recent works with microwaves investigating properties of open systems which can be described by an effective Hamiltonian. This ranges from spectral properties like modifications to level dynamics, width distribution and coupling fidelity to spatial properties like intensity distributions and complexness parameter which describes the non‐orthogonality of eigenfunctions.
Improving membrane binding as a design strategy for amphipathic peptide hormones: 2‐helix variants of PYY3‐36
Authors: Pedersen Søren L. , Bhatia Vikram K. , Jurt Simon , Paulsson Johan F. , Pedersen Maria H. , Jorgensen Rasmus , Holst Birgitte , Stamou Dimitrios , Vrang Niels , Zerbe Oliver , Jensen Knud J.
Published: August 2012

It has been hypothesized that amphipathic peptides might bind to membranes prior to activating their cognate receptors, but this has proven difficult to test. The peptide hormone PYY3‐36 is believed to perform its appetite‐suppressing actions through binding to hypothalamic Y2 receptors. It has been proposed that PYY3‐36 via its amphipathic α‐helix binds to the plasma membrane prior to receptor docking. Here, our aim was to study the implication of this hypothesis using new analogs of PYY3‐36. We first studied membrane binding of PYY3‐36. Next, we designed a series of PYY3‐36 analogs to increase membrane‐binding affinity by substituting the N‐terminal segment with a de novo designed α‐helical, amphipathic sequence. These 2‐helix variants of PYY3‐36 were assembled by solid‐phase peptide synthesis. Pharmacological studies demonstrated that even though the native peptide sequence was radically changed, highly active Y2 receptor agonists were generated. A potent analog, with a Kd of 4 nM for membranes, was structurally characterized by NMR in the membrane‐bound state, which clearly showed that it formed the expected 2‐helix. The topology of the peptide–micelle association was studied by paramagnetic relaxation enhancement using a spin label, which confirmed that the hydrophobic residues bound to the membrane. Our studies further support the hypothesis that PYY3‐36 associates with the membrane and indicate that this can be used in the design of novel molecules with high receptor binding potency. These observations are likely to be generally important for peptide hormones and biopharmaceutical drugs derived from them. This new 2‐helix variant of PYY3‐36 will be useful as a tool compound for studying peptide–membrane interactions. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis and properties of cyclic gomesin and analogues
Authors: Machado Alessandra , Fázio Marcos A. , Miranda Antonio , Daffre Sirlei , Machini M. Teresa
Published: August 2012

Gomesin (Gm) was the first antimicrobial peptide (AMP) isolated from the hemocytes of a spider, the Brazilian mygalomorph Acanthoscurria gomesiana. We have been studying the properties of this interesting AMP, which also displays anticancer, antimalarial, anticryptococcal and anti‐Leishmania activities. In the present study, the total syntheses of backbone‐cyclized analogues of Gm (two disulfide bonds), [Cys(Acm)2,15]‐Gm (one disulfide bond) and [Thr2,6,11,15,d‐Pro9]‐Gm (no disulfide bonds) were accomplished, and the impact of cyclization on their properties was examined. The consequence of simultaneous deletion of pGlu1 and Arg16‐Glu‐Arg18‐NH2 on Gm antimicrobial activity and structure was also analyzed. The results obtained showed that the synthetic route that includes peptide backbone cyclization on resin was advantageous and that a combination of 20% DMSO/NMP, EDC/HOBt, 60 °C and conventional heating appears to be particularly suitable for backbone cyclization of bioactive peptides. The biological properties of the Gm analogues clearly revealed that the N‐terminal amino acid pGlu1 and the amidated C‐terminal tripeptide Arg16‐Glu‐Arg18‐NH2 play a major role in the interaction of Gm with the target membranes. Moreover, backbone cyclization practically did not affect the stability of the peptides in human serum; it also did not affect or enhanced hemolytic activity, but induced selectivity and, in some cases, discrete enhancements of antimicrobial activity and salt tolerance. Because of its high therapeutic index, easy synthesis and lower cost, the [Thr2,6,11,15,d‐Pro9]‐Gm analogue remains the best active Gm‐derived AMP developed so far; nevertheless, its elevated instability in human serum may limit its therapeutic potential. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
Plasma‐assisted MBE growth of ZnO on GaAs substrate with a ZnSe buffer layer
Authors: Zhao Kuaile , Ye Lijia , Tamargo M. C. , Shen A.
Published: July 2012

ZnO thin films were grown by plasma‐assisted MBE on GaAs substrates with ZnSe buffer layers. GaAs with different orientations: (001), (111) A, and (111) B were investigated. X‐ray diffraction measurements showed that ZnO grown on (111) B GaAs substrates have the best structural quality. All the samples showed good optical qualities as indicated by room temperature photoluminescence measurements. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A revision of sexual mixing matrices in models of sexually transmitted infection
Authors: Walker Robert , Nickson Carolyn , Lew Jie‐Bin , Smith Megan , Canfell Karen
Published: July 2012

Two sexual mixing matrices previously used in models of sexually transmitted infections (STIs) are intended to calculate the probability of sexual interaction between age groups and sexual behaviour subgroups. When these matrices are used to specify multiple criteria for how people select sexual partners (such as age group and sexual behaviour class), their conditional probability structure means that they have in practice been prone to misuse. We constructed revised mixing matrices that incorporate a corrected conditional probability structure and then used one of them to examine the effect of this revision on population modelling of STIs. Using a dynamic model of human papillomavirus (HPV) transmission as an example, we examined changes to estimates of HPV prevalence and the relative reduction in age‐standardised HPV incidence after the commencement of publicly funded HPV vaccination in Australia. When all other model specifications were left unchanged, the revised mixing matrix initially led to estimates of age‐specific oncogenic HPV prevalence that were up to 11% higher than our previous models at certain ages. After re‐calibrating the model by modifying unobservable parameters characterising HPV natural history, the revised mixing matrix yielded similar estimates to our previous models, predicting that vaccination would lead to relative HPV incidence reductions of 43% and 85% by 2010 and 2050, respectively, compared with 43% and 86% using the unrevised mixing matrix formulation. Our revised mixing matrix offers a rigorous alternative to commonly used mixing matrices, which can be used to reliably and explicitly accommodate conditional probabilities, with appropriate re‐calibration of unobservable model parameters. Copyright © 2012 John Wiley & Sons, Ltd.
Responses of PTTH‐producing neurosecretory neurons in Lymantria dispar caterpillars exposed to cadmium
Authors: Ilijin Larisa , Vlahović Milena , Mrdaković Marija , Mirčić Dejan , Todorović Dajana , Lazarević Jelica , Perić‐Mataruga Vesna
Published: August 2012

Lymantria dispar, as most invasive insect species, is very adaptable and reacts quickly to changing environment. Neuroendocrine system first reacts to stress in insects, and specific neurohormonal reorganization may be used in early heavy metal risk assessment. Prothoracicotropic neurohormones (PTTH) control ecdysteroid synthesis (morphogenetic and stress hormones) in insects. In this article, we report the presence of PTTH immunoreactive molecules in L2' dorsolateral neurosecretory neurons (nsn) in caterpillar brains and changes after exposure to pollutant stress of different intensity. For 3 days, after molting into the 4th instar, caterpillars of Lymantria dispar were fed with a high wheat germ diet without (control) or with added cadmium (experimental groups: 10, 30, 100, 250 μg Cd/g dry food weight). Changes in PTTH producing L2' nsn and differences in the intensity of protein bands in the region of PTTH molecular mass (Mr 11–15 kDa) were analyzed. The number of L2' neurons tended to decrease except in the group given the highest cadmium concentration (250 μg). The neurons were enlarged after acute treatment especially in the group given the highest cadmium concentration. The size of L2' nsn nuclei was decreased only in the group fed with 30 μg Cd. Protein band intensity in the Mr region of PTTH remained unchanged in all groups except for the group given the diet with the highest Cd concentration. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 770–779, 2014.
Fabry‐Perot‐based Layer Stacks for Ellipsometric Encoding
Authors: Beck Uwe , Hönig Dirk , Schneider Stefan , Domnick Ralph , Belzner Mathias , Hertwig Andreas , Stephanowitz Ralph , Sahre Mario , Weise Matthias
Published: August 2012

Public, hidden, and forensic features either encoded or directly legible are used for authentication. Fabry‐Perot layer stacks as information carriers in combination with imaging ellipsometry as optical read‐out system provide all‐in‐one anti‐counterfeiting capability that may establish the new security level “encoded forensic”. Different layer designs are described with regard to all three security levels: public features (e.g. color and tilt effect) perceptible by the human eye, hidden features (e.g. spectroscopic response in the UV or IR), and forensic features (ellipsometric quantities Ψ and Δ as a function of wavelength λ and angle of incidence AOI). Physically uncloneable functions (PUF) could be realized as a result of a multi‐material and a multi‐parameter deposition approach as well as by means of specific design features of the Fabry‐Perot layer stack. Hence, they are not subject to any reverse engineering strategies. Examples of stratified, micro‐structured, and laser‐modified Fabry‐Perot layer systems are considered that may be used at all perception levels (e.g. human eye, bar code reader, and imaging ellipsometry) for authentication against product counterfeiting and related areas.
Transparente leitfähige Elektroden
Authors: Müller‐Meskamp Lars , Sachse Christoph , Kim Yong Hyun , Furno Mauro , May Christian , Leo Karl
Published: August 2012

Organische photoaktive Bauelemente wie organische Solarzellen oder OLEDs benötigen mindestens eine transparente leitfähige Elektrodenschicht. Auf Glassubstraten und für erste Produkte werden dazu überwiegend IndiumZinn‐Oxid (ITO) Dünnschichten eingesetzt. ITO hat hervorragende Eigenschaften und ist seit Jahren in der Industrie erprobt. Für den Einsatz in kostengünstigen, leichten und flexiblen Produkten ist das spröde und relativ teure Material aber nicht optimal, so dass neue Marktchancen für alternative Elektrodenmaterialien bestehen.

Kandidaten dafür sind alternative transparente Oxide, netzwerkbasierte Elektroden aus Metallnanodrähten oder Carbon Nanotubes, leitfähige Polymere, Metalldünnschichten oder Graphene. Transparente Elektrodenschichten aus diesen Materialien sind teilweise noch im experimentellen Stadium, können aber in Zukunft ITO in ausgewählten Applikationen ersetzen.
Laserakustik für Schicht‐ und Oberflächenprüfung
Authors: Schneider Dieter , Leson Andreas , Berger Lutz‐Michael
Published: August 2012

In dem Beitrag wird eine laserakustische Methode für die zerstörungsfreie Prüfung von Schichten und Werkstoffoberflächen vorgestellt. Sie beruht auf der Messung der Dispersion von akustischen Oberflächenwellen, die mit kurzen Laserimpulsen angeregt werden. Dabei wird ausgenutzt, dass die Ausbreitungsgeschwindigkeit der Welle in beschichteten und oberflächenmodifizierten Werkstoffen von der Frequenz abhängt. Aus der Messung der Oberflächenwellendispersion kann man auf wichtige Eigenschaften der Randschichten schließen.

An drei Beispielen wird demonstriert, dass man mit der Messmethode sehr unterschiedliche Probleme lösen kann. Die Verschleißeigenschaften von diamantähnlichen Kohlenstoffschichten, die nur wenige Nanometer dick sind, konnten bewertet werden. Der Elastizitätsmodul thermischer Spitzschichten, deren Dicke mehrere hundert Mikrometer beträgt, wurde gemessen. Dies erlaubt, die Defektstruktur der Schichten zu bewerten. Die Tiefe von Bearbeitungsrandschichten, die beim Trennen von Halbleiterwerkstoffen entstehen, wurde bestimmt.
Capture and Characterization of a Iron(II) Precursor Complex [FeCl3(Hpipz)(pipz)] for Coordination Polymer Synthesis from a Piperazine Melt
Authors: Schönfeld Fabian , Meyer Larissa Valerie , Winter Florian , Niehaus Oliver , Rodewald Ute Ch. , Pöttgen Rainer , Müller‐Buschbaum Klaus
Published: August 2012

By reacting iron(III) chloride with a melt of piperazine, the complex [FeCl3(Hpipz)(pipz)] is formed containing equatorial chloride anions and axial piperazine ligands constituting a trigonal bipyramidal coordination polyhedron. The obtained product is an example for the capture of a precursor complex under melt conditions for the formation of coordination polymers and is thus of limited crystallinity. Characterization was achieved by solution and refinement of the crystal structure by a combination of powder X‐ray diffraction, geometrical optimization methods, 57Fe‐Mößbauer, and IR spectroscopy, magnetic investigations, and elemental analysis. In addition, corroboration by X‐ray single crystal data was used to prove the results from powder diffraction as suitable single crystals were finally achieved by modification of the synthesis with the auxiliary solvent pyridine.
Synthesis and Crystal Structure of the Highly Reduced ­Metalate Ba3[Ir(CN)3]
Authors: Jach Franziska , Höhn Peter , Senyshyn Anatoliy , Ruck Michael , Kniep Rüdiger
Published: July 2012

Greenish gray microcrystalline powders of Ba3[Ir(CN)3] were prepared from pressed pellets of mixtures of Ba2N, iridium, NaCN, and graphite at 1020 K under inert conditions. Neutron diffraction data at 293 K revealed the crystal structure of the Ir compound (P63/m (no. 176), a = 9.2277(8) Å, c = 5.7878(6) Å) to be isostructural to Sr3[Co(CN)3] and Ba3[Co(CN)3]. The trigonal‐planar complex [Ir3(CN)3]6– is surrounded by nine Ba2+ ions forming a tricapped trigonal prism. Elongated C–N distances and low vibrational frequencies in the highly reduced iridium complex are similar to those observed in the corresponding cobalt compounds.
Synthesis and X‐ray Structural Characterization of the Polymeric Cluster Compound [Hg3(O2SePh)(SePh)5]n
Authors: Stieler Rafael , Back Davi F. , Tirloni Bárbara , Burrow Robert A. , Lang Ernesto S.
Published: August 2012

Two synthetic routes to prepare [Hg3(O2SePh)(SePh)5]n and its structural characterization are presented in this paper. This compound results either from the partial oxidation of mercury phenylselenolate clusters or from a mixture of its components with defined stoichiometry. This compound was observed in almost all of our reactions as a by‐product, during the development of the synthesis of new mercury selenolate clusters. It was now characterized by single‐crystal X‐ray diffractometry, elemental analysis, and infrared spectroscopy.
A Survey of Diabetes Prevalence in Zoo‐housed Primates
Authors: Kuhar C. W. , Fuller G. A. , Dennis P. M.
Published: July 2012

In humans, type II diabetes mellitus is a condition in which the pancreas is capable of producing insulin but cells do not appropriately respond to insulin with an uptake of glucose. While multiple factors are associated with type II diabetes in humans, a high calorie diet and limited exercise are significant risk factors for the development of this disease. Zoo primates, with relatively high caloric density diets and sedentary lifestyles, may experience similar conditions that could predispose them to the development of diabetes. We surveyed all Association of Zoos and Aquariums (AZA) facilities with primates in their collections to determine the prevalence of diabetes, diagnosis and treatment methods, and treatment outcomes. Nearly 30% of responding institutions reported at least one diabetic primate in their current collection. Although the majority of reported cases were in Old World Monkeys (51%), all major taxonomic groups were represented. Females represented nearly 80% of the diagnosed cases. A wide variety of diagnosing, monitoring, and treatment techniques were reported. It is clear from these results diabetes should be considered prominently in decisions relating to diet, weight and activity levels in zoo‐housed primates, as well as discussions surrounding animal health and welfare. Zoo Biol. 32:63‐69, 2013. © 2012 Wiley Periodicals, Inc.
Tinospora cordifoliaconsumption ameliorates changes in kidney chondroitin sulphate/dermatan sulphate in diabetic rats
Authors: Joladarashi Darukeshwara , Chilkunda Nandini D. , Salimath Paramahans V.
Published: July 2012

Diabetes is known to alter kidney extracellular matrix (ECM) components. Chondroitin sulphate (CS)/dermatan sulphate (DS), an ECM component, which plays an essential role in kidney is altered during diabetes. The focus of this study has been to examine the effect ofTinospora cordifolia(TC) consumption, a potent plant widely used to treat diabetes, on kidney CS/DS. Experimentally induced diabetic rats were fed with diet containingTCat 2·5 and 5 % levels and the effect of it on kidney CS/DS was examined. The CS/DS content and CS:heparan sulphate ratio which was decreased during diabetic condition were ameliorated inTC-fed groups. Disaccharide composition analysis of CS/DS by HPLC showed that decreases in ‘E’ units and degree of sulphation were modulated in 5 %TC-fed groups. Apparent molecular weight of purified CS/DS from the control rat kidney was found to be 38 kDa which was decreased to 29 kDa in diabetic rat kidney. Rats in 5 %TC-fed groups showed chain length of 38 kDa akin to control rats. Expression of chondroitin 4-O-sulfotransferase-1, dermatan 4-O-sulfotransferase-1 andN-acetylgalactosamine 4 sulphate 6-O-sulfotransferase, enzymes involved in the synthesis of ‘E’ units which was reduced during diabetic condition, was significantly contained in the 5 %TC-fed group. Purified CS/DS from 5 %TC-fed group was able to bind higher amounts of ECM components, namely type IV collagen and laminin, when compared with untreated diabetic rats. The present results demonstrate that consumption of a diet containingTCat the 5 % level modulates changes in kidney CS/DS which were due to diabetes.
The Civic Origins of Progressive Policy Change: Combating Violence against Women in Global Perspective, 1975–2005
Authors: HTUN MALA , WELDON S. LAUREL
Published: July 2012

Over the past four decades, violence against women (VAW) has come to be seen as a violation of human rights and an important concern for social policy. Yet government action remains uneven. Some countries have adopted comprehensive policies to combat VAW, whereas others have been slow to address the problem. Using an original dataset of social movements and VAW policies in 70 countries over four decades, we show that feminist mobilization in civil society—not intra-legislative political phenomena such as leftist parties or women in government or economic factors like national wealth—accounts for variation in policy development. In addition, we demonstrate that autonomous movements produce an enduring impact on VAW policy through the institutionalization of feminist ideas in international norms. This study brings national and global civil society into large-n explanations of social policy, arguing that analysis of civil society in general—and of social movements in particular—is critical to understanding progressive social policy change.
Collective Action, Clientelism, and Connectivity
Authors: SHAMI MAHVISH
Published: July 2012

Backed by studies finding only limited propensity for free-riding when communities have an interest in self-provision, the last few decades have seen a surge of interest in community-based development. A major caveat to the “second wave” of collective action studies, however, is that collective action often breaks down under hierarchical social relationships. This is unfortunate news for developing countries’ rural societies, which are often entrenched in patron-client networks. Using a natural experiment found in the construction of a motorway, the article finds that clientelist relationships do not, in and by themselves, block peasant collective action. Rather, it is the interaction between clientelism and isolation that empowers patrons to block community-based projects. Peasants in connected villages face no such constraints, but instead rely on their patrons’ assistance in collective projects, making the hierarchical network an additional resource.
Long-term tracking of plasma phospholipid fatty acid concentrations and their correlation with the dietary intake of marine foods in newly diagnosed diabetic patients: results from a follow-up of the HUNT Study, Norway
Authors: Lindberg Morten , Midthjell Kristian , Bjerve Kristian S.
Published: July 2012

Analysis of long-chainn-3 andn-6 fatty acid (FA) concentrations is used to evaluate their potential health effects in epidemiological studies, and, recently, also to counsel patients with a suboptimal intake ofn-3 FA. Data on the method's ability to track and detect differences within and between individuals in appropriate populations are, however, lacking. The present study provides such data for twenty-nine plasma phospholipid (PL) FA concentrations and indices measured in 214 newly diagnosed type 2 diabetic patients at baseline and after 3 years. 20 : 3n-6 and the 20 : 4n-6:20 : 3n-6 ratio showed the highest tracking coefficients (Spearman'sr0·68), while DHA, EPA and PLN3-index (EPA+DHA) coefficients were 0·60, 0·47 and 0·55, respectively. Fish consumption measured simultaneously with EPA, DHA, sumn-3 and PLN3 index showed Spearman's correlation coefficients of 0·47, 0·44, 0·48 and 0·49, respectively, decreasing to 0·20, 0·19, 0·22 and 0·21 when measured 3 years apart. The within-subject CV of EPA, DHA and PLN3 index were 39·9, 14·3 and 18·0 %, respectively. The corresponding between-subject CV were 33·6, 16·5 and 18·7 %, while the reference change values were 112, 41 and 52 %. In conclusion, PLn-3 FA concentrations showed a significant long-term tracking and were positively correlated with marine food intake. Analytical precision, biological variability, reference change value and the index of individuality of EPA, DHA and PLN3 index are similar to commonly used clinical biomarkers, supporting their validity as dietary markers in clinical and epidemiological work.
THE POLITICS OF ENLIGHTENMENT: FROM PETER GAY TO JONATHAN ISRAEL
Authors: de DIJN ANNELIEN
Published: August 2012

According to the textbook version of history, the Enlightenment played a crucial role in the creation of the modern, liberal democracies of the West. Ever since this view – which we might describe as the modernization thesis – was first formulated by Peter Gay, it has been repeatedly criticized as misguided: a myth. Yet, as this paper shows, it continues to survive in postwar historiography, in particular in the Anglophone world. Indeed, Gay's most important and influential successors – historians such as Robert Darnton and Roy Porter – all ended up defending the idea that the Enlightenment was a major force in the creation of modern democratic values and institutions. More recently, Jonathan Israel's trilogy on the Enlightenment has revived the modernization thesis, albeit in a dramatic new form. Yet, even Israel's work, as its critical reception highlights, does not convincingly demonstrate that the Enlightenment, as an intellectual movement, contributed in any meaningful way to the creation of modern political culture. This conclusion raises a new question: if the Enlightenment did not create our modern democracies, then what did it do? In answer to that question, this paper suggests that we should take more seriously the writings of enlightened monarchists like Nicolas-Antoine Boulanger. Studying the Enlightenment might not allow us to understand why democratic political culture came into being. But, as Boulanger's work underscores, it might throw light on an equally important problem: why democracy came so late in the day.
BREAKING BRITANNIA'S BOUNDS? LAW, SETTLERS, AND SPACE IN BRITAIN'S IMPERIAL HISTORIOGRAPHY
Authors: LAIDLAW ZOË
Published: August 2012

Historians of the British empire recast their understanding of relations between the metropole and its peripheries in the late twentieth century, notably through the work of the ‘British world’ network and the ‘new imperial historians’. The former emphasized the material, emotional, and financial links between British colonizers across the imperial diaspora; the latter focused on the empire's impact on Britain, particularly in terms of ‘everyday’ experience. This article critically reviews recent interventions, which extend and challenge these approaches by seeking new ways to juxtapose the macro with the micro, and balance the exceptional with the quotidian; by adopting a more transnational (or global) approach to colonialism; and by rethinking the categories of ‘settler’ and ‘colonizer’. Collectively, these works question the traditional frameworks within which both colonialism and the British empire have been understood. In conclusion, the article considers their impact on the vibrant field of Britain's colonial legal history.