bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical manifestations of primary pulmonary extranodal marginal zone lymphoma of mucosa‐associated lymphoid tissue in Japanese population
Authors: Ogusa Eriko , Tomita Naoto , Ishii Yoshimi , Takasaki Hirotaka , Hattori Yukako , Matsumoto Chihiro , Ishigatsubo Yoshiaki
Published: January 2012

We retrospectively analysed 16 cases of newly diagnosed pulmonary mucosa‐associated lymphoid tissue (MALT) lymphoma in the Japanese population. The disease was found on the basis of examination findings in 14 cases, and clinical manifestations in 2. According to the extensive staging procedure, four patients had concomitant gastric involvement. Primary treatment involved surgery alone in two patients; surgery followed by rituximab (R)‐containing chemotherapy in two; R‐containing chemotherapy alone in 11; and chemoradiotherapy without R in one. Over the median observation period of 28 months, disease progression was recorded in three patients, but all 16 patients were alive at the end of the observation period. One patient was treated with R alone and achieved partial remission; subsequent tentative surgery showed no evidence of residual lymphoma. It has been 72 months of progression‐free survival after the diagnosis. Primary pulmonary MALT lymphoma exhibited an indolent clinical course. R has potential as a therapeutic agent in patients with pulmonary MALT lymphoma. Copyright © 2012 John Wiley & Sons, Ltd.
Malignant melanoma, breast cancer and other cancers in patients with Parkinson's disease
Authors: Rugbjerg Kathrine , Friis Søren , Lassen Christina Funch , Ritz Beate , Olsen Jørgen H.
Published: January 2012

Previous studies report an atypical cancer pattern among patients with Parkinson's disease. Here, we evaluate the cancer pattern among people diagnosed with Parkinson's disease in an extension of our previous cohort study. For this Danish population‐based cohort study, we identified 20,000 people with Parkinson's disease diagnosed in 1977–2006, from the National Danish Hospital Register. Cohort members were followed up for cancer in the Danish Cancer Registry until December 31, 2008, and their incidence rates of cancer were compared to age‐, sex‐ and calendar period‐specific rates in the general population as standardized incidence rate ratios (SIRs). In subanalyses, we estimated the risk for cancer among patients with early onset Parkinson's disease and we also compared breast tumor characteristics among women with Parkinson's disease to that of a control group. The overall cancer risk in our cohort was decreased [SIR = 0.86; 95% confidence interval (CI) = 0.83–0.90], as were those for smoking‐related (SIR = 0.65; 95% CI = 0.60–0.70) and nonsmoking‐related cancers (SIR = 0.79; 95% CI = 0.71–0.86). The cohort had increased risks for malignant melanoma (SIR = 1.41; 95% CI = 1.09–1.80), nonmelanoma skin cancer (SIR = 1.29; 95% CI = 1.18–1.39) and female breast cancer (SIR = 1.17; 95% CI = 1.02–1.34). Among patients with early onset Parkinson's disease, the risk for cancer was comparable to that of the general population. Of breast tumor characteristics, only grade of malignancy differed between Parkinson's disease women and controls. This study confirms a lower cancer risk among people with Parkinson's disease. Increased risks for malignant melanoma, nonmelanoma skin cancer and breast cancer might be due to shared risk factors with Parkinson's disease.
Epigenetically mediated downregulation of the differentiation‐promoting chaperon protein CRABP2 in astrocytic gliomas
Authors: Campos Benito , Warta Rolf , Chaisaingmongkol Jittiporn , Geiselhart Lea , Popanda Odilia , Hartmann Christian , von Deimling Andreas , Unterberg Andreas , Plass Christoph , Schmezer Peter , Herold‐Mende Christel
Published: January 2012

Impairment of endogenous differentiation pathways like retinoic acid (RA) signaling seems to be a central pathogenetic event in astrocytic gliomas. Among others, expression of the differentiation‐promoting RA chaperon protein cellular retinoic acid binding protein 2 (CRABP2) is extenuated in high‐grade gliomas. Against this background, we aimed at identifying potential pathomechanisms underlying reduced CRABP2 expression in these tumors. Using MassARRAY methylation analysis, we detected extensive CpG methylation upstream of the CRABP2 gene locus in a study sample comprising 100 astrocytic gliomas of WHO Grade II to IV. Compared to nontumorous control samples, tumors revealed increased CpG methylation and methylation levels were inversely correlated to CRABP2 mRNA expression. Substantiating our in situ findings, CRABP2 mRNA levels increased in glioma cell lines after exposure to the demethylating agent 5‐aza‐2′‐deoxycytidine. Finally, a distinct CpG methylation signature distinguished between primary glioblastoma on the one hand and the group of astrocytoma WHO II–III and secondary glioblastoma on the other hand. Altogether, our observations suggest that epigenetic silencing of CRABP2 might contribute to an immature phenotype in glioma cells.
The RON‐receptor regulates pancreatic cancer cell migration through phosphorylation‐dependent breakdown of the hemidesmosome
Authors: Yu Peter T. , Babicky Michele , Jaquish Dawn , French Randy , Marayuma Karly , Mose Evangeline , Niessen Sherry , Hoover Heather , Shields David , Cheresh David , Cravatt Benjamin F. , Lowy Andrew M.
Published: January 2012

The recepteur d'origine nantais (RON) receptor tyrosine kinase is overexpressed and stimulates invasive growth in pancreatic cancer cells, yet the mechanisms that underlie RON‐mediated phenotypes remain poorly characterized. To better understand RON function in pancreatic cancer cells, we sought to identify novel RON interactants using multidimensional protein identification analysis. These studies revealed plectin, a large protein of the spectrin superfamily, to be a novel RON interactant. Plectin is a multifunctional protein that complexes with integrin‐β4 (ITGB4) to form hemidesmosomes, serves as a scaffolding platform crucial to the function of numerous protein signaling pathways and was recently described as an overexpressed protein in pancreatic cancer (Bausch D et al., Clin Cancer Res 2010; Kelly et al., PLoS Med 2008;5:e85). In this study, we demonstrate that on exposure to its ligand, macrophage‐stimulating protein, RON binds to plectin and ITGB4, which results in disruption of the plectin‐ITGB4 interaction and enhanced cell migration, a phenotype that can be recapitulated by small hairpin ribosomal nucleic acid (shRNA)‐mediated suppression of plectin expression. We demonstrate that disruption of plectin‐ITGB4 is dependent on RON and phosphoinositide‐3 (PI3) kinase, but not mitogen‐activated protein kinase (MEK), activity. Thus, in pancreatic cancer cells, plectin and ITGB4 form hemidesmosomes which serve to anchor cells to the extracellular matrix (ECM) and restrain migration. The current study defines a novel interaction between RON and plectin, provides new insight into RON‐mediated migration and further supports efforts to target RON kinase activity in pancreatic cancer.
Bioactive glass microspheres as reinforcement for improving the mechanical properties and biological performance of poly(ε‐caprolactone) polymer for bone tissue regeneration
Authors: Lei Bo , Shin Kwan‐Ha , Noh Da‐Young , Koh Young‐Hag , Choi Won‐Young , Kim Hyoun‐Ee
Published: January 2012

This study examined the utility of sol–gel‐derived bioactive glass microspheres (BGMs) as a reinforcement to improve the mechanical properties and biological performance of poly(ε‐caprolactone) (PCL) polymer. All of the PCL‐BGMs composites produced, with a variety of BGMs contents (10, 20, and 30 wt %), showed a uniform distribution of the BGMs in the PCL matrix, particularly owing to their spherical shape and small size. This led to a considerable increase in the elastic modulus from 93 ± 12 MPa to 635 ± 179 MPa with increasing BGMs content from 0 to 30 wt %. Furthermore, the addition of the BGMs to the PCL polymer significantly increased the hydrophilicity of the PCL‐BGMs composites, which led to a higher water absorption and degradation rate. The PCL‐BGMs composite with a BGMs content of 30 wt % showed vigorous growth of apatite crystals with a high aspect ratio on its surface after soaking in the simulated body fluid for 7 days, resulting in the creation of a porous carbonate hydroxyapatite layer. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Formulation and in vitro characterization of PEGylated chitosan and polyethylene imine polymers with thrombospondin‐I gene bearing pDNA
Authors: Mehmet Saka Ongun , Bozkir Asuman
Published: January 2012

An ideal gene carrier is required both in safety and efficiency for transfection. We examined the use of water soluble chitosan and polyethyleneimine as a carrier for anti‐angiogenic protein, TSP‐1 coded, in gene delivery. The aim of this study was to synthesize and characterize polyethylene glycol conjugated cationic polymers to increase anti‐angiogenic gene transfection and reduce possible cytotoxicity. Gel electrophoresis study showed strong DNA binding ability of modified cationic polymers. Also structural properties of pegylated polymers were confirmed by 1H‐NMR. We investigated in vitro properties of PEG conjugated and coated particles which were observed between 145 and 250 nm with the positive zeta potential value. In addition, the chitosan‐based DNA complexes did not induce remarkable cytotoxicity against MCF‐7 cells. Due to low cytotoxicity, we observed high transfection efficiency at chitosan‐based formulations compared with PEI ones. Although transfection studies carried on in vitro conditions, we measured slight increases at transfection with PEGylation. PEG‐conjugated chitosan formulations can be a promising candidate due to its efficiency in condensing and transfection of pDNA, its low cytotoxicty and comparatively high encapsulation degree. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Evaluation of the electron momentum density of crystalline systems from ab initio linear combination of atomic orbitals calculations
Authors: Erba Alessandro , Pisani Cesare
Published: January 2012

Alternative techniques are presented for the evaluation of the electron momentum density (EMD) of crystalline systems from ab initio linear combination of atomic‐orbitals calculations performed in the frame of one‐electron self‐consistent‐field Hamiltonians. Their respective merits and drawbacks are analyzed with reference to two periodic systems with very different electronic features: the fully covalent crystalline silicon and the ionic lithium fluoride. Beyond one‐electron Hamiltonians, a post‐Hartree–Fock correction to the EMD of crystalline materials is also illustrated in the case of lithium fluoride. © 2012 Wiley Periodicals, Inc.
MoleculaRnetworks: An integrated graph theoretic and data mining tool to explore solvent organization in molecular simulation
Authors: Mooney Barbara Logan , Corrales L.René , Clark Aurora E.
Published: January 2012

This work discusses scripts for processing molecular simulations data written using the software package R: A Language and Environment for Statistical Computing. These scripts, named moleculaRnetworks, are intended for the geometric and solvent network analysis of aqueous solutes and can be extended to other H‐bonded solvents. New algorithms, several of which are based on graph theory, that interrogate the solvent environment about a solute are presented and described. This includes a novel method for identifying the geometric shape adopted by the solvent in the immediate vicinity of the solute and an exploratory approach for describing H‐bonding, both based on the PageRank algorithm of Google search fame. The moleculaRnetworks codes include a preprocessor, which distills simulation trajectories into physicochemical data arrays, and an interactive analysis script that enables statistical, trend, and correlation analysis, and other data mining. The goal of these scripts is to increase access to the wealth of structural and dynamical information that can be obtained from molecular simulations. © 2012 Wiley Periodicals, Inc.
thermocalc — A poor man's approach to computational thermochemistry
Authors: Hellweg Arnim , Diedenhofen Michael , Huniar Uwe
Published: January 2012

We present thermocalc, a Perl module to perform the automated calculation of atomization energies and heats of formation for lists of molecules. The methods used are based on density functional theory and second‐order perturbation theory to ensure that data sets of medium sized to large molecules can be run at reasonable throughput rates. The quantum chemical calculations are performed using the program package TURBOMOLE in a three‐step protocol. In a first step, a pre‐optimization of the structure and a zero‐point energy calculation are performed. As second step, a geometry optimization is being carried out, and the last step is a single point energy calculation. The level of theory used in the different steps can be modified by the user to allow for customized protocols. The performance of example protocols is investigated on different test sets of molecules. In the course of this work, a simple, but efficient one‐parameter correction term based on the shared electron numbers has been developed, which reduces the error of calculated heats of formation significantly. © 2012 Wiley Periodicals, Inc.
Treatment of an industrial chemical waste‐water using a granular activated carbon adsorption‐microwave regeneration process
Authors: Liu Qing‐Song , Wang Peng , Zhao Shan‐Shan , Zhang Wei
Published: January 2012

BACKGROUND: Industrial waste‐water is posing an ever‐greater environmental hazard. Recently, a process for purification combining activated carbon adsorption and microwave regeneration has drawn much attention. In this study, the effectiveness of this process for the treatment of industrial waste‐water from a chemical plant was tested.

RESULTS: The effects of various factors including solution pH, granular activated carbon (GAC) dosage and contact time on the adsorption efficiency of organic compounds were studied. The regeneration of the exhausted GAC under microwave radiation was investigated, and the optimal conditions were: microwave power 400 W, radiation time 3 min for 10 g GAC. Under the optimal conditions the regenerated GAC recovered 97.6% of its original adsorption capacity. Repetitive uses of the GAC showed that it maintained a stable performance in the first few repetitions, but a decrease was observed after further repetitions. A GAC weight loss of about 10% at the sixth repetition was observed and a decrease in the surface area and increase in the surface basicity were observed for the regenerated GAC. Economic evaluation of the microwave regeneration process suggested that the total cost was about 24.3% of the GAC price at a pilot scale.

CONCLUSIONS: A satisfactory regeneration of the chemical waste‐water exhausted GAC could be achieved under microwave radiation. The GAC adsorption‐microwave regeneration process was applicable for the treatment of this chemical waste‐water. Copyright © 2012 Society of Chemical Industry
Recyclable plant tannin‐chelated Rh(III) complex catalysts for aqueous–organic biphasic hydrogenation of quinoline
Authors: Mao Hui , Liao Xuepin , Zhang Wenhua , shi Bi
Published: January 2012

BACKGROUND: Synthetic ligands have conventionally been used for the preparation of homogenous Rh complex catalyst but biomass has rarely been utilized for this purpose. In the present investigation, plant tannins (natural polyphenols) were used as water‐soluble ligands for the preparation of homogenous Rh3+ complex catalysts.

RESULTS: Based on X‐ray photoelectron spectroscopy (XPS) and proton nuclear magnetic resonance (HNMR) analyses, the preparation mechanism of these complex catalysts was proven to involve chelating interactions between Rh3+ and the adjacent phenolic hydroxyls of plant tannins. As a result, the use of plant tannin promoted aqueous‐organic biphasic interactions and the plant tannin‐chelated Rh3+ complex catalysts exhibited much higher catalytic activity than commercial Rh complex catalysts in the biphasic hydrogenation of quinoline. Furthermore, the plant tannin‐chelated Rh3+ complex can be reused three times without significant loss of catalytic activity

CONCLUSION: Our experimental results suggested that black wattle tannin (BWT) can be used as water‐soluble ligands for the preparation of highly active and recyclable Rh3+ complex catalysts. Copyright © 2012 Society of Chemical Industry
An optimization‐oriented green design for methanol plants
Authors: Taghdisian Hosein , Farhadi Fatola , Pishvaie Mahmoud Reza
Published: January 2012

BACKGROUND: A new design for a methanol plant is proposed in which CO2 addition, as one of the important parameters, is used to optimize the synthesis gas composition. An attempt has been made to assess the environmental features as well as the process operability of the proposed plant, in which the required CO2 is provided from reformer flue gas. As a starting point, simulation of a conventional reference methanol case (RMC) and also the proposed green integrated methanol case (GIMC) are performed to obtain operational and kinetic parameters. In order to compare properly GIMC and RMC, the objective function is defined so that SynGas production, and thereby methanol production, in the GIMC is equal to that of the RMC.

RESULTS: In the optimization the optimum values of decision variables are calculated using a genetic algorithm. In the best case, the eco‐efficiency indicators of GIMC would decrease to 330.3 kg CO2 tonne−1 MeOH, which is 15% lower than that of RMC. The environmental damage cost of 2.9 million dollars could also be prevented in GIMC when compared with RMC.

CONCLUSION: It was found that the CO2 needed in GIMC could be provided by an environmentally friendly process and that the GIMC is a cleaner process compared with RMC. Furthermore, the proposed GIMC would be capable of reducing CO2 emission while its mitigation potential depends significantly on the type of solvent employed in the GIMC. The results obtained show that environmental damage cost would be important and should be considered in the process design. Copyright © 2012 Society of Chemical Industry
Scale‐up of MSC under hypoxic conditions for allogeneic transplantation and enhancing bony regeneration in a rabbit calvarial defect model
Authors: Yew Tu‐Lai , Huang Tung‐Fu , Ma Hsiao‐Li , Hsu Yuan‐Tong , Tsai Chih‐Chien , Chiang Chao‐Ching , Chen Wei‐Ming , Hung Shih‐Chieh
Published: January 2012

To realize the therapeutic potential of mesenchymal stem cells (MSCs), we aimed to develop a method for isolating and expanding New Zealand rabbit MSCs in a great scale. Rabbit MSCs expanded under hypoxic and normoxic conditions were compared in terms of replication capacity, differentiation potential, and the capacity for allogeneic transplantation in a calvarial defect model. The cells from all tested rabbits were expanded more rapidly when plated at low‐density under hypoxic conditions compared to under normoxic conditions. Moreover, cells expanded under hypoxic conditions increased in the potential of osteoblastic, adipocytic, and chondrocytic differentiation. More importantly, radiographic analysis and micro‐CT measurement of bone volume revealed the hypoxic cells when transplanted in the calvarial defects of another rabbit increased in the ability to repair bone defect compared to the normoxic cells. Six weeks after allogeneic transplantation of hypoxic MSCs, histological analysis revealed a callus spanned the length of the defect, and several bone tissues spotted in the implant. At 12 weeks, new bone had formed throughout the implant. Using BrdU labeling to track the transplanted cells, the hypoxic cells were more detected in the newly formed bone compared to the normoxic cells. For defects treated with allogeneic MSCs, no adverse host response could be detected at any time‐point. In conclusion, we have developed a robust method for isolation and expansion of rabbit MSCs by combining low‐density with hypoxic culture, which can be applied for the design of clinical trials in allogeneic transplantation of MSCs for bone healing. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1213–1220, 2012
PRISM (Pictorial Representation of Illness and Self Measure): A new method for the assessment of suffering after trauma
Authors: Wittmann Lutz , Schnyder Ulrich , Büchi Stefan
Published: January 2012

This pilot study tested the validity of a 1‐item visual assessment method originally developed to evaluate suffering in chronic illness that has been adapted for use with patients who have been exposed to traumatic events. The Pictorial Representation of Illness and Self Measure (PRISM) was administered 5 times during the course of a posttraumatic stress disorder (PTSD) treatment outcome study (N = 29). The PRISM scores declined significantly under trauma‐focused psychotherapy and differentiated between participants with and without PTSD diagnoses. Test‐retest reliability over a 6‐month period was high (r = .85). PRISM showed significant correlations with measures of PTSD, depression, and psychopathology symptom load (r = −.38 to r = −.81; convergent validity). At the same time, PRISM was not significantly related to trauma history (discriminant validity). Illustrations of symptom time courses indicated that PRISM was more closely related to trauma‐specific psychopathology than to nontrauma‐specific psychopathology (discriminant validity) and sensitive to change. In summary, PRISM appears to be a valid tool for the assessment of trauma‐related suffering and adds to multimethod approaches in trauma research.
Targeting of Multidrug‐Resistant Human Ovarian Carcinoma Cells With Anti‐P‐Glycoprotein Antibody Conjugates
Authors: Fowers Kirk D. , Kopeček Jindřich
Published: January 2012

A monoclonal antibody (mAb) to P‐glycoprotein (Pgp), UIC2, is used as a targeting moiety for N‐(2‐hydroxypropyl)methacrylamide (HPMA) copolymer/drug [(meso chlorin e6 mono(N‐2‐aminoethylamide) (Mce6) or doxorubicin (DOX)] conjugates to investigate their cytotoxicity towards the Pgp‐expressing human ovarian carcinoma cell line A2780/AD. The binding, internalization, and subcellular trafficking of a fluorescein labeled UIC2 targeted HPMA copolymer are studied and show localization to the plasma membrane with limited internalization. The specificity of the UIC2‐targeted HPMA copolymer/drug conjugates are confirmed using the sensitive cell line A2780 that does not express Pgp.

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Numerical Assessment of PE 80 and PE 100 Pipe Lifetime Based on Paris‐Erdogan Equation
Authors: Frank Andreas , Hutař Pavel , Pinter Gerald
Published: January 2012

Summary: A novel accelerated fracture mechanics extrapolation procedure based on cyclic test with cracked round bar (CRB) specimens was verified by a correlation of real pipe failure time to simulated failure times at a temperature of 60 °C. The procedure was applied to predict the long‐term failure of modern PE 80 and PE 100 pipes 23 °C. Moreover, the used stress intensity factor concept also allows to consider the impact of arbitrary additional loading situations like soil loads or point loads and to assess pipe lifetime under complex loading situations.
Towards the Antimicrobial Finishing of Poly(isoprene)
Authors: Kienberger Julia , Kreutzwiesner Elisabeth , Noormofidi Nadja , Klarholz Ingo , Harms Carsten , Slugovc Christian
Published: January 2012

Summary: Anionically polymerised (poly)isoprene was functionalized with cysteamine applying thiol‐ene click chemistry. Subsequent quaternisation of the primary amino groups gave polymers with antimicrobial activity against Listeria monocytogenes, Eschericchia coli, Pseudomonas fluorescens and Staphylococcus aureus as revealed from tests performed according to the Japanese Industrial Standard Z2801:2000. The novel polymers feature sufficient thermal stability for the compounding with commodity polymers such as poly(propylene) and might be used as a non leaching additive to finish commodity polymers with antimicrobial acitivity.
Simulation of the Long Term Behaviour of Plastics Components
Authors: Stommel M. , Naumann T.
Published: January 2012

Summary: This paper presents a method to model the mechanical behavior of polymers over a wide time‐ and load‐range by means of finite element analyses. The method includes a material model as well as the determination of material parameters to calibrate the material model. As a special feature of this method the model is calibrated only by using creep data that are commonly available in material data bases. So the procedure improves the simulation of the long time behavior of plastic‐components without an additional experimental effort. In combination with time‐temperature‐superposition principle, the temperature dependency of the long term behavior is represented, too. The simulation results are validated by creep experiments on an example part.
Analytical and Numerical Methods for the Design of Maddock Mixers in Single Screw Plasticizing Technology
Authors: Olbrich Michael , Zitzenbacher Gernot , Hochenauer Christoph , Kneidinger Christian , Lawlor Vincent
Published: January 2012

Summary: In single screw plasticizing technology dispersive mixing elements, i.e., axial and spiral Maddock shear heads, are often used to improve the melt quality. Mathematical models are necessary to efficiently design the mixing section. An analytical model for the design of Maddock mixers is presented in this work. In addition, a CFD‐software package is employed to determine the flow and pressure field for different geometries and processing conditions. For the design and process analysis of fluted dispersive mixers the validity and potential of simplified analytical solutions are compared to more versatile and detailed CFD‐simulations.
Preparation and Thermal Characterization of PTFE/PES Nanocomposites
Authors: Antonioli Diego , Laus Michele , Sparnacci Katia , Deregibus Simone , Kapeliouchko Valerj , Poggio Tiziana , Zuccheri Giampaolo , Passeri Rosita , Boarino Luca
Published: January 2012

Summary: PTFE/PES composites were prepared by precipitation of Radel A® into a PTFE latex containing nanoparticles with average diameters of 48 nm and spherical shape. Several samples were prepared by varying the relative ratio between the Radel A® and PTFE content. The combination of SEM and AFM analysis indicates that the precipitation of Radel A in the presence of PTFE leads mainly, if not exclusively, to a bimodal mixture of the two homoparticles. The fractionated crystallization behaviour of these samples is revealing of the PTFE dispersion degree within the Radel A® matrix. When the PTFE amount is lower than 2%, a perfect PTFE nanoparticle dispersion is obtained. When the amount of PTFE is comprised between 5 and 30%, larger PTFE clusters are obtained that, after melting, coalesce and crystallize at higher temperatures depending on the crystallization propensity of their individual heterogeneous nuclei. Finally, in case of samples 40%, only one crystallization exotherm is observed at 310 °C indicating the formation of very large clusters that after melting coalesce into wide domains.
Analysis of Molecular and Morphological Effects on Slow Crack Growth in Modern PE Pipe Grades by Cyclic Fracture Mechanics Tests
Authors: Redhead Anita , Pinter Gerald , Frank Andreas
Published: January 2012

Summary: Three different polyethylene (PE) pipe grades as well as three different lots of one of the grades were investigated by cyclic tests with cracked round bar (CRB) specimens, concerning resistance to slow crack growth. To enhance the test sensibility and proof its applicability for a quick quality assurance method various molecular and morphological characterizations on compression molded plates were carried out, with special attention on the influence of molecular and morphological differences, as well as lot to lot variations on the resistance to slow crack growth. The cyclic CRB tests allowed a ranking of the different pipe grades and lots with short testing times per material and testing machine, as a function of failure time as well as of crack initiation time with further reduction of testing time of about 50%. Moreover the ranking corresponded to the expectations based on the molecular and morphological properties of the materials, where only minor changes in the molecular mass distribution and the co‐monomer concentration in case of lot to lot variations were proofed reliably.
Effect of the Mixture Composition on Shear and Extensional Rheology of Recycled PET and ABS Nanocomposites
Authors: Kracalik Milan , Laske Stephan , Witschnigg Andreas , Holzer Clemens
Published: January 2012

Summary: Recycled PET as well as ABS ‐ organomodified montmorillonite nanocomposites were prepared via melt compounding in a counter‐rotating twin screw extruder. The topological changes in polymer matrices as dependency on clay modification have been evaluated from dynamic experiments in the shear flow using low amplitude oscillatory measurements. Flow characteristics of all studied organoclay nanocomposites showed shear‐thinning behavior at low frequencies. Filling of PET with some organoclays led to degradation reactions, which were reflected by lower magnitudes of viscosity and storage modulus in the range of higher frequencies as compared to unfilled polymer matrix. On the contrary, no degradation during the processing of different organoclays with recycled ABS has been observed.
Numerical Simulation of Crack Growth in Polyethylene Composites by Means of the Cohesive Zone Model
Authors: Janko Marian , Ecker Werner , Pinter Gerald , Kolednik Otmar
Published: January 2012

Summary: The cohesive zone model is used for the numerical simulation of crack growth in homogeneous specimens made of two different grades of polyethylene (PE) as well as in PE‐bimaterials. The material data and the shapes of the cohesive function are deduced from experimental data by Ivankovic et al., Eng. Fract. Mech. 71, 2004, 657–668 and Ting et al., Polym. Eng. Sci. 46, 2006, 763–777. Fracture toughness parameters are evaluated from the simulated load versus displacement curves. The results show a significant influence of the arrangement of the two PE‐grades in the bimaterial specimens, caused by both the different material properties and the different characteristic parameters of the cohesive function.
Mathematical Modeling of Acid‐Catalyzed 1,3‐Propanediol Polymerization
Authors: Mueller Philipp A. , Rajagopalan Bhuma , Congalidis John P. , Murphy Edward R.
Published: January 2012

A reaction mechanism for the polymerization of 1,3‐propanediol is proposed for two acid catalysts. Population and mass balance equations are derived for small molecules and for polymeric species of chain distributions distinguishable in terms of protonation state and end group functionality. Since the sulfuric acid catalyzed process has two types of polymer linkages, the derivation of the moment equations is challenging. The reverse reactions are also accounted thus creating a moment closure problem. A mass transfer model is developed to predict reaction mixture water content. The Sanchez‐Lacombe equation of state is used to calculate phase behavior and species partitioning. Optimization of selected parameters is accomplished by comparison to laboratory data resulting in a fully predictive model.

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Does the presence of the palmaris longus tendon influence median nerve function?
Authors: Werner Robert A. , Spiegelberg Teresa
Published: January 2012

Introduction: The objective of this study was to determine if the presence or absence of a palmaris longis tendon influenced the function of the median nerve across the wrist. The primary hypothesis was that the presence of a palmaris longus tendon would be associated with more median nerve entrapment at the wrist. Methods: This was a cross‐sectional study. Subjects were recruited at a screening of dental professionals. The median and ulnar sensory nerve latencies across the wrist (relative prolongation of the median compared with the ulnar) and the presence or absence of the palmaris longus tendon were the primary outcome measures. Results: A total of 462 subjects were recruited into the study of which 16.2% lacked a palmaris longus tendon. There was no difference in the median nerve function or the percentage with a 0.5 ms prolongation of the median sensory latency when comparing subjects with and without a palmaris longus tendon. Conclusions: The presence of a palmaris longus tendon does not influence the median nerve function across the wrist. Muscle Nerve 45: 895–896, 2012
Application of hyperpolarized [1‐13C]lactate for the in vivo investigation of cardiac metabolism
Authors: Mayer Dirk , Yen Yi‐Fen , Josan Sonal , Park Jae Mo , Pfefferbaum Adolf , Hurd Ralph E. , Spielman Daniel M.
Published: January 2012

In addition to cancer imaging, 13C‐MRS of hyperpolarized pyruvate has also demonstrated utility for the investigation of cardiac metabolism and ischemic heart disease. Although no adverse effects have yet been reported for doses commonly used in vivo, high substrate concentrations have lead to supraphysiological pyruvate levels that can affect the underlying metabolism and should be considered when interpreting results. With lactate serving as an important energy source for the heart and physiological lactate levels one to two orders of magnitude higher than for pyruvate, hyperpolarized lactate could potentially be used as an alternative to pyruvate for probing cardiac metabolism. In this study, hyperpolarized [1‐13C]lactate was used to acquire time‐resolved spectra from the healthy rat heart in vivo and to measure dichloroacetate (DCA)‐modulated changes in flux through pyruvate dehydrogenase (PDH). Both primary oxidation of lactate to pyruvate and subsequent conversion of pyruvate to alanine and bicarbonate could reliably be detected. Since DCA stimulates the activity of PDH through inhibition of PDH kinase, a more than 2.5‐fold increase in bicarbonate‐to‐substrate ratio was found after administration of DCA, similar to the effect when using [1‐13C]pyruvate as the substrate. Copyright © 2012 John Wiley & Sons, Ltd.
A practical network coding and routing scheme based on maximum flow combination
Authors: Wu Lianlong , Curran Kevin
Published: January 2012

Network coding is a novel field of information theory and coding theory. It is a breakthrough over the traditional store‐and‐forward routing methods by allowing coding of two or more packets together. From an information flow aspect, multiple flows could be overlapped in a routing scheme. Hence the theoretical upper bound of multicast capacity could be achieved by network coding. In this project, a complete routing and coding scheme is constructed to realize the maximum multicast transportation task. In order to implement the scheme, the paths of multiple max‐flows are determined. Edges are divided into overlapped and normal type based on the merged max‐flows. The transmitting data are represented using packets in a specific format. Multicast, forward and coding operations are defined to transmit data at the nodes. The nodes are classified according to the type of operation. A dynamic coding and routing algorithm is proposed to route packets gradually from source node to destinations in topological sorting order by the three operations on the path of merged max‐flows. We show that the use of simple XOR operations can satisfy most of the network topologies. The running time of the algorithm presented here is less than 1 second for most of the benchmark and random datasets. Copyright © 2012 John Wiley & Sons, Ltd.
ETHICAL CULTURE AND THE VALUE‐BASED APPROACH TO INTEGRITY MANAGEMENT: A CASE STUDY OF THE DEPARTMENT OF CORRECTIONAL SERVICES
Authors: Webb Werner Nicholaas
Published: January 2012

In this article the author proposes that a compliance‐based approach be supplemented by a value‐based approach in attempts to reduce public service malfeasance. The compliance‐based approach per se should not be regarded as the panacea for corruption. It could be argued that such an approach not only reduces malfeasance, but creates additional layers of oversight and reduces public service efficiency and effectiveness. In fact, additional structures and policies could create opportunities for corruption. Conversely, the value‐based approach seeks to promote the ethical culture within a public institution. This research builds on an existing body of literature concerned with the ethical culture of organisations. This author identified the Department of Correctional Services as a case study to determine how the promotion of an ethical culture could enhance the implementation of corruption prevention policies. The author makes use of a survey to collect data. The captured data is analysed and subjected to exploratory factor analysis. A total of 11 factors of ethical culture are provided and the correlation between factors is provided with the Pearson's correlation coefficient. The findings indicate that the promotion of some factors of ethical culture coincides with reduced levels of malfeasance. Copyright © 2012 John Wiley & Sons, Ltd.
CONFRONTING CORRUPTION IN THE HEALTH SECTOR IN VIETNAM: PATTERNS AND PROSPECTS
Authors: Vian Taryn , Brinkerhoff Derick W. , Feeley Frank G. , Salomon Matthieu , Vien Nguyen Thi Kieu
Published: January 2012

Corruption in Vietnam is a national concern that could derail health sector goals for equity, access and quality. Yet, there is little research on vulnerabilities to corruption or associated factors at the sectoral level. This article examines current patterns and risks of corruption in Vietnam's health sector and reviews strategies for addressing corruption in the future. The article builds on the findings and discussion at the sixth Anti‐Corruption Dialogue between the Vietnamese government and the international donor community. Development partners, government agencies, Vietnamese and international non‐governmental organisations, media representatives and other stakeholders explored what is known about important problems such as informal payments, procurement corruption and health insurance fraud. The participants proposed corruption‐reduction interventions in the areas of administrative oversight, transparency initiatives and civil society participation and health reforms to change incentives. The analysis assesses the prospects for success of these interventions, given the Vietnamese institutional context, and draws conclusions relevant to addressing health sector corruption in other countries. Copyright © 2012 John Wiley & Sons, Ltd.
INSTITUTIONAL TRUST AND OPINIONS OF CORRUPTION
Authors: Sööt Mari‐Liis , Rootalu Kadri
Published: January 2012

The aim of this study was to examine individual factors that influence attitudes towards corruption. The study used data from an original opinion survey conducted in the Estonian public sector. The results demonstrate that trust in institutions, age and nationality are the most important individual factors to influence public officials' awareness of corruption and the extent to which they are ready to condemn corrupt and unethical behaviour. Copyright © 2012 John Wiley & Sons, Ltd.
Microstructure and mechanical properties of isotactic polypropylene composite with two‐scale reinforcement
Authors: Chen Yan‐Hui , Zhang Zheng‐Chi , Hsiao Benjamin S. , Tang Jian‐Hua , Li Zhong‐Ming
Published: January 2012

Isotactic polypropylene (iPP) composite with two‐scale reinforcement structure, i.e. nanoscale shish–kebab structure and micron‐scale glass fiber (GF) with orientation, was fabricated by an oscillatory shear injection molding (OSIM) technology. The oscillatory shear flow provided by the OSIM gave rise to a high fraction of shish–kebab structures in the iPP composite, characterized by X‐ray scattering technique. On the other hand, the oscillatory shear flow oriented GFs in the iPP composite, which was revealed by scanning electron microscopy measurement. The iPP composite with this two‐scale reinforcement structure exhibited simultaneously remarkably enhanced tensile strength and impact strength. Fracture mechanism of this iPP composite was also proposed. Copyright © 2012 John Wiley & Sons, Ltd.
Photo‐regulated phase transition of poly(ethylene glycol) derivative containing azobenzene group
Authors: Hu Jie , Wang Xiang , Zheng Shiheng
Published: January 2012

A photo‐responsive and thermo‐responsive poly(ethylene glycol) derivative containing azobenzene group was synthesized. Its photoisomerization kinetics was investigated by the UV–vis spectra, and the pseudo‐first‐order rate constants (kt and kc) were determined to be 1.5 × 10−2 and 9.3 × 10−2 s−1, respectively. It is found that the phase transition behavior can be tuned theoretically through photoirradiation between 26.6°C and 36.7°C. Finally, it is worthy to note that the changes of the lower critical solution temperature occur repeatedly upon successive irradiation of UV and visible light. Copyright © 2012 John Wiley & Sons, Ltd.
Multi‐responsive polymeric microcontainers for potential biomedical applications: synthesis and functionality evaluation
Authors: Bilalis Panayiotis , Efthimiadou Eleni K. , Chatzipavlidis Alexandros , Boukos Nikos , Kordas George C.
Published: January 2012

Temperature and pH responsive poly(N‐isopropylacrylamide‐co‐methacrylic acid) (P(NIPAAm‐co‐MAA)) microcontainers with encapsulated magnetic nanoparticles in the shell were prepared by a two‐stage distillation precipitation polymerization. PMAA@Fe3O4/P(NIPAAm‐co‐MAA) core–shell nanoparticles were synthesized by the second‐stage polymerization of NIPAAm, MAA and N, N′‐methylenebisacrylamide as crosslinker in the presence of magnetic nanoparticles and PMAA as core. These novel triple‐functional microcontainers were prepared by selective removal of the PMAA core in water. Daunorubicin hydrochloride (DNR) was loaded into the microcontainers and the release profile was studied by UV–visible spectroscopy. The synthesized nanostructures were characterized with transmission and scanning electron microscopy, X‐ray diffraction and Fourier transform infrared spectroscopy. The magnetic properties were evaluated by vibrating sample magnetometry. The shrink and swelling behavior was studied by dynamic light scattering. Copyright © 2012 Society of Chemical Industry
The basicity of sulfonamides and carboxamides. Theoretical and experimental analysis and effect of fluorinated substituent
Authors: Shainyan Bagrat. A. , Chipanina Nina. N. , Oznobikhina Larisa. P.
Published: January 2012

The basicity of a series of sulfonamides and carboxamides with respect to protonation and hydrogen‐bonded complex formation with phenol was investigated by calculations using the Becke three‐parameter hybrid functional combined with Lee–Yang–Parr correlation functional with the 6‐311G** and 6‐311++G** basis sets and by infrared spectroscopy. The effect of fluorinated substituent was studied for the two series. The proton affinity of nitrogen in sulfonamides is higher than oxygen, in contrast to carboxamides, which are protonated at oxygen. The phenyl group in benzenesulfonamide increases the basicity of both heteroatoms, but more strongly of the nitrogen, whereas in benzamide the effect on the two heteroatoms is about the same. The CF3 group equally decreases the basicity of nitrogen and oxygen atoms in sulfonamides and carboxamides. The second fluorinated substituent decreases the basicity of oxygen in (CF3CO)2NH more strongly than of nitrogen. For sulfonamides, the same effect results in the reverse of the center of basicity from nitrogen in (MeSO2)2NH to oxygen in (CF3SO2)2NH. All studied carboxamides give H‐complexes via the carbonyl oxygen, whereas for sulfonamides two types of H‐complexes, with the OH···N and OH···O=S, were found theoretically, the latter being more stable. The exception is bisimide (CF3SO2)2NH, for which only the OH···O=S complex is stable. Experimentally, only the oxygen‐bound complexes are observed. Analysis of the natural charges revealed an ‘abnormal’ increase of the electron density on the NH group by electron‐acceptor substituents in CF3SO2NHR, which was explained using the natural bond orbital analysis by loosening of the S–N bond because of orbital interactions with the σ*S−N orbital. Copyright © 2012 John Wiley & Sons, Ltd.
Insights into the molecular mechanism of tolerance to carboxylic acid amide (CAA) fungicides in Pythium aphanidermatum
Authors: Blum Mathias , Gisi Ulrich
Published: January 2012

BACKGROUND: Tolerance to the oomycete‐specific carboxylic acid amide (CAA) fungicides is a poorly understood mechanism in Pythium species. The root‐rot and damping‐off causative agent Pythium aphanidermatum and the CAA fungicide mandipropamid (MPD) were used to investigate the molecular basis of CAA tolerance.

RESULTS: Five genes putatively involved in carbohydrate synthesis were identified and characterised: one chitin synthase gene, PaChs, and four cellulose synthase genes PaCesA1 to PaCesA4, of which PaCesA3 encodes the MPD target enzyme. These genes were differentially expressed throughout the life cycle of P. aphanidermatum. Mycelium treated with MPD concentrations slightly affecting mycelial growth did not cause a change in PaCesA3 expression nor a strong upregulation of PaCesA homologues. The high tolerance level of P. aphanidermatum and the lack of PaCesA upregulation imply that MPD tolerance is the result of a specific amino acid configuration in the cellulose synthase 3 (CesA3) target enzyme. Indeed, P. aphanidermatum displays the amino acid L1109 which is also associated with MPD resistance in artificial mutants of Phytophthora species.

CONCLUSION: It is concluded that MPD tolerance in P. aphanidermatum is not caused by compensatory mechanisms but most likely by an inherent target‐site configuration in PaCesA3 that hinders MPD binding to the enzyme pocket. Copyright © 2012 Society of Chemical Industry
Variation in the sensitivity of Callosobruchus (Coleoptera: Bruchidae) acetylcholinesterase to the organophosphate insecticide malaoxon: effect of species, geographical strain and food type
Authors: Gbaye Olajire A , Holloway Graham J , Callaghan Amanda
Published: January 2012

BACKGROUND: Bruchid beetles, Callosobruchus species, are serious pests of economically important grain legumes; their activity in stores is often controlled by the use of synthetic insecticides. Esterases are known to be involved in insecticide resistance in insects. However, there is a dearth of information on esterase activity in the genus Callosobruchus. In this study, the effect of species, geographical strain and food type on the variation in acetylcholinesterase (AChE) activity and its inhibition by malaoxon (malathion metabolite) was investigated using an in vitro spectrophotometric method.

RESULT: AChE activity varied significantly among species and strains and also among legume type used for rearing them. Generally, irrespective of species, strain or food type, the higher the AChE activity of a population, the higher is its inhibition by malaoxon. C. chinensis had the highest AChE activity of the species studied, and in the presence of malaoxon it had the lowest remaining AChE activity, while C. rhodesianus retained the highest activity.

CONCLUSION: A first‐hand knowledge of AChE activity in regional Callosobruchus in line with the prevailing food types should be of utmost importance to grain legume breeders, researchers on plant materials for bruchid control and pesticide manufacturer/applicators for a robust integrated management of these bruchids. Copyright © 2012 Society of Chemical Industry