bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical and photocatalytic properties of TiO2 films modified with oxides and gold
Authors: Busko T. , Dmytrenko O. , Kulish M. , Prylutskyy Y. , Shokhovets S. , Gobsch G. , Vityuk N. , Eremenko A. , Tkach V.
Published: March 2013

Films consisting of TiO2/ZrO2/SiO2 undoped and doped with Au nanoparticles were synthesized by the sol‐gel method. The films were characterized with X‐ray diffraction (XRD), scanning electron microscopy (SEM), spectroscopic ellipsometry (SE) and optical absorption (OA) methods. The XRD study demonstrates the formation of TiO2 anatase nanocrystals and Au nanoparticles. SE and OA measurements of the undoped films showed no significant absorption in the spectral range of 400–1000 nm. Doping with Au nanoparticles resulted in the appearance of a surface plasmon resonance (SPR) absorption band at 600 nm as well as weaker absorption bands in the 300–500 nm region. The observed changes in optical properties agreed with the enhanced photocatalytic activity of Au‐doped TiO2/ZrO2/SiO2 films with gold compared to undoped films. The photocatalytic activity was evaluated by the photodegradation of the organic dye Rhodamine B. Under optimized conditions, the photodecomposition rate of the doped films was several times larger than that of the undoped films. Films of TiO2, TiO2/ZrO2/SiO2 and ternary oxides were investigated.
Physical, chemical and biological properties of micro‐arc deposited calcium phosphate coatings on titanium and zirconium‐niobium alloy
Authors: Legostaeva E.V. , Kulyashova K.S. , Komarova E.G. , Epple M. , Sharkeev Y.P. , Khlusov I.A.
Published: March 2013

A comparative investigation of the physical, chemical and biological properties of micro‐arc deposited calcium phosphate coatings on titanium and zirconium‐niobium substrates was performed. Calcium phosphate coatings on titanium have a higher surface density, porosity and pore size, and a more homogeneous surface topography. Under the same conditions, calcium phosphate coatings on zirconium‐niobium have a relief topography, but their surface density, porosity and pore size were all smaller. X‐ray diffraction of the coatings showed that the coatings on titanium were X‐ray amorphous whereas the coatings on zirconium‐niobium consisted of a mixture of crystalline CaZr4(PO4)6, ZrP2O7, and ZrO2. These differences are due to different electrical and thermophysical characteristics of substrates and passivating films on their surfaces. The coatings were shown to be biocompatible by in‐vitro cell culture experiments.
Microstructure, mechanical and biological properties of zirconium alloyed with niobium after severe plastic deformation
Authors: Sharkeev Y.P. , Eroshenko A.Y. , Kulyashova K.S. , Fortuna S.V. , Suvorov K.A. , Epple M. , Prymak O. , Sokolova V. , Chernousova S.
Published: March 2013

A comparative investigation of microstructure, mechanical and biological properties for zirconium alloyed with niobium in coarse‐grained and ultra‐fine grained states is presented. The temperature and deformation regimes of multi‐stage abc‐pressing resulted in ultra‐fine grained states with an average size of the structural elements in the range of 0.28–0.55 μm, depending on the accumulated strain during pressing. The increase of the accumulated strain at each stage of pressing increased the uniformity of the structure. The microhardness increased by 50% with increased accumulated strain during the severe plastic deformation. Between the microhardness and the average size of the structural elements, a linear dependence was found, indicating a Hall‐Petch relationship. The alloy had a good biocompatibility as shown by an MTT test with osteoblasts (MG‐63 cell line). The good mechanical properties (microhardness) of zirconium alloyed with niobium in the ultra‐fine grained state make it suitable for medical applications, e. g. as implant material.
Platinum nanoparticles on the surface of silica modified with silicon hydride groups
Authors: Tertykh V. A. , Ivashchenko N. A. , Yanishpolskii V. V. , Khainakov S. A.
Published: March 2013

Platinum‐containing nanocomposites were synthesized by the in situ reduction of hexachloroplatinate water solution with silicon hydride groups grafted to the silica surface. Transmission electron microscopy showed that the quantity of supported metal influenced the size of the formed platinum nanoparticles. A decrease of the metal content in the composite from 1.5 to 0.3 wt% resulted in the formation of particles with sizes in a range from 27 to 3–9 nm. X‐ray diffraction, X‐ray photoelectron spectroscopy and temperature‐programmed reduction were applied to investigate the state of the metal on the carrier surface.
Corticomuscular coherence in asymptomatic first‐degree relatives of patients with essential tremor
Authors: Raethjen Jan , Muthuraman Muthuraman , Kostka Achim , Nahrwold Martin , Hellriegel Helge , Lorenz Delia , Deuschl Günther
Published: March 2013

Background

Essential tremor (ET) follows an autosomal dominant type of inheritance in the majority of patients, yet its genetic basis has not been identified. Its exact origin is still elusive, but coherence measurements between electromyography tremor bursts and electroencephalography unequivocally demonstrate a correlation.

Methods

We tested these measurements in 37 healthy first‐degree relatives (children) of patients with essential tremor (ET) and a group of 37 age‐matched and sex‐matched controls. Pooled coherence spectra of the maximally coherent electroencephalogram electrodes were computed for ET relatives and controls.

Results

The maximal coherence and its frequency were significantly higher in ET relatives than in controls during the pinch grip task and during slow hand movements. Electromyography amplitude (root‐mean‐square) was slightly but significantly greater in ET relatives, whereas 2‐Hz to 40‐Hz power and spectral peak frequency were not different.

Conclusions

The presymptomatic alteration in corticomuscular interaction may reflect a role of genetic factors. © 2013 Movement Disorder Society
Solvability of a class of impulsive damped vibration problems
Authors: Bai Liang , Dai Binxiang
Published: March 2013

In this paper, a class of impulsive damped vibration problems are considered. Existence results are obtained by using variational method and critical point theorem. The obtained results are also valid and new even if the impulsive damped vibration problem is reduced to impulsive Hamiltonian system and Hamiltonian system. Examples are presented to illustrate the feasibility and effectiveness of the results. Copyright © 2013 John Wiley & Sons, Ltd.
Computational inversion of electron micrographs using L2‐gradient flows—convergence analysis
Authors: Chen C. , Xu G.
Published: March 2013

A gradient flow‐based explicit finite element method (L2GF) for reconstructing the 3D density function from a set of 2D electron micrographs has been proposed in recently published papers. The experimental results showed that the proposed method was superior to the other classical algorithms, especially for the highly noisy data. However, convergence analysis of the L2GF method has not been conducted. In this paper, we present a complete analysis on the convergence of L2GF method for the case of using a more general form regularization term, which includes the Tikhonov‐type regularizer and modified or smoothed total variation regularizer as two special cases. We further prove that the L2‐gradient flow method is stable and robust. These results demonstrate that the iterative variational reconstruction method derived from the L2‐gradient flow approach is mathematically sound and effective and has desirable properties. Copyright © 2013 John Wiley & Sons, Ltd.
Auraptene suppresses inflammatory responses in activated RAW264 macrophages by inhibiting p38 mitogen‐activated protein kinase activation
Authors: Lin Shan , Hirai Shizuka , Goto Tsuyoshi , Sakamoto Tomoya , Takahashi Nobuyuki , Yano Masamichi , Sasaki Takao , Yu Rina , Kawada Teruo
Published: March 2013

Scope

Inflammation plays a key role in obesity‐related pathologies such as insulin resistance and type 2 diabetes. Hypertrophied adipocytes trigger the enhancement of macrophage infiltration and the release of various proinflammatory factors in obese adipose tissue. In this study, we examined whether auraptene, a citrus‐fruit–derived compound, could suppress the production of inflammatory factors that mediate the interaction between adipocytes and macrophages.

Methods and results

Experiments using a co‐culture system of 3T3‐L1 adipocytes and RAW264 macrophages showed that auraptene reduced the production of nitric oxide and tumor necrosis factor‐α. In RAW264 macrophages, auraptene also suppressed the inflammation induced by either LPS or the conditioned medium derived from 3T3‐L1 adipocytes. In addition, auraptene inhibited the phosphorylation of the p38 mitogen‐activated protein kinase and suppressed the production of proinflammatory mediators in activated macrophages.

Conclusion

Our findings indicate that auraptene exhibits anti‐inflammatory properties by suppressing the production of inflammatory factors that mediate the interaction between adipocytes and macrophages, suggesting that auraptene is a valuable food‐derived compound with a potential to attenuate chronic inflammation in adipose tissue and to improve obesity‐related insulin resistance.
Modifying and validating the Composite International Diagnostic Interview (CIDI) for use in Nepal
Authors: Ghimire Dirgha J. , Chardoul Stephanie , Kessler Ronald C. , Axinn William G. , Adhikari Bishnu P.
Published: March 2013

Background: Efforts to develop and validate fully‐structured diagnostic interviews of mental disorders in non‐Western countries have been largely unsuccessful. However, the principled methods of translation, harmonization, and calibration that have been developed by cross‐national survey methodologists have never before been used to guide such development efforts. The current report presents the results of a rigorous program of research using these methods designed to modify and validate the Composite International Diagnostic Interview (CIDI) for an epidemiological survey in Nepal. Methods: A five‐step process of translation, harmonization, and calibration was used to modify the instrument. A blinded clinical reappraisal design was used to validate the instrument. Results: Preliminary interviews with local mental health expert led to a focus on major depressive episode, mania/hypomania, panic disorder, post‐traumatic stress disorder, generalized anxiety disorder, and intermittent explosive disorder. After an iterative process of multiple translations‐revisions guided by the principles developed by cross‐national survey methodologists, lifetime DSM‐IV diagnoses based on the final Nepali CIDI had excellent concordance with diagnoses based on blinded Structured Clinical Interview for DSM‐IV (SCID) clinical reappraisal interviews. Conclusions: Valid assessment of mental disorders can be achieved with fully‐structured diagnostic interviews even in low‐income non‐Western settings with rigorous implementation of replicable developmental strategies. Copyright © 2013 John Wiley & Sons, Ltd.
Dealing with clinical heterogeneity in meta‐analysis. Assumptions, methods, interpretation
Authors: Kriston Levente
Published: March 2013

Objective

There is an ongoing debate how to interpret findings of meta‐analyses when substantial clinical heterogeneity is present among included trials. The aim of the present study was to demonstrate various ways of dealing with clinical heterogeneity along with underlying assumptions and interpretation. A recent meta‐analysis on long‐term psychodynamic psychotherapy (LTPP) was used as an illustrative example. Method: Re‐analysis of published data including calculation of a prediction interval, heterogeneity tests, Bayesian meta‐analysis, meta‐regression, and subgroup analysis to explore and interpret summary estimates in clinically heterogeneous studies. Results: Meta‐analytic results and their implications varied considerably depending on whether and how clinical heterogeneity was addressed. Conclusions: Whether or not to trust summary estimates in meta‐analysis depends largely on the subjective relevance of clinical heterogeneity present. No single analysis and interpretation strategy can be valid in every context or paradigm, thus, reflection of own beliefs on the role of heterogeneity is needed. Copyright © 2013 John Wiley & Sons, Ltd.
Sparse spectral deconvolution algorithm for noncartesian MR spectroscopic imaging
Authors: Bhave Sampada , Eslami Ramin , Jacob Mathews
Published: March 2013

Purpose

To minimize line shape distortions and spectral leakage artifacts in MR spectroscopic imaging (MRSI).

Methods

A spatially and spectrally regularized non‐Cartesian MRSI algorithm that uses the line shape distortion priors, estimated from water reference data, to deconvolve the spectra is introduced. Sparse spectral regularization is used to minimize noise amplification associated with deconvolution. A spiral MRSI sequence that heavily oversamples the central k‐space regions is used to acquire the MRSI data. The spatial regularization term uses the spatial supports of brain and extracranial fat regions to recover the metabolite spectra and nuisance signals at two different resolutions. Specifically, the nuisance signals are recovered at the maximum resolution to minimize spectral leakage, while the point spread functions of metabolites are controlled to obtain acceptable signal‐to‐noise ratio.

Results

The comparisons of the algorithm against Tikhonov regularized reconstructions demonstrates considerably reduced line‐shape distortions and improved metabolite maps.

Conclusion

The proposed sparsity constrained spectral deconvolution scheme is effective in minimizing the line‐shape distortions. The dual resolution reconstruction scheme is capable of minimizing spectral leakage artifacts. Magn Reson Med 71:469–476, 2014. © 2013 Wiley Periodicals, Inc.
Muscle volume as a predictor of maximum force generating ability in the plantar flexors post‐stroke
Authors: Knarr Brian A. , Ramsay John W. , Buchanan Thomas S. , Higginson Jill S. , Binder‐Macleod Stuart A.
Published: March 2013

Introduction: Post‐stroke muscle weakness is commonly thought to be the result of a combination of decreased voluntary activation and decreased maximum force generating ability (MFGA). We assessed the ability of muscle volumes obtained using MRI to estimate the MFGA of the plantar flexor muscle group in individuals post‐stroke. Methods: MRI was used to measure muscle volume of the plantar flexor muscle group in 17 individuals with post‐stroke hemiparesis. A modified burst superimposition test was used to measure force of volitional contraction and predict the MFGA of the plantar flexors. Results: While muscle volume obtained by means of MRI provided information on the overall size of muscle, it overestimated the force generating ability of the paretic plantar flexors. Conclusions: Results suggest that MRI‐derived muscle volume underestimates the functional impairment in individuals post‐stroke. Interestingly, the central activation ratio had a strong relationship with the maximum volitional force of contraction. Muscle Nerve 48: 971–976, 2013
Fatigue and recovery from dynamic contractions in men and women differ for arm and leg muscles
Authors: Senefeld Jonathon , Yoon Tejin , Bement Marie Hoeger , Hunter Sandra K.
Published: March 2013

Introduction: Whether there is a gender difference in fatigue and recovery from maximal velocity fatiguing contractions and across muscles is not understood. Methods: Sixteen men and 19 women performed 90 isotonic contractions at maximal voluntary shortening velocity (maximal velocity concentric contractions, MVCC) with the elbow flexor and knee extensor muscles (separate days) at a load equivalent to 20% maximal voluntary isometric contraction (MVIC). Results: Power (from MVCCs) decreased similarly for men and women for both muscles (P > 0.05). Men and women had similar declines in MVIC of elbow flexors, but men had greater reductions in knee extensor MVIC force and MVIC electromyogram activity than women (P < 0.05). The decline in MVIC and power was greater, and force recovery was slower for the elbow flexors compared with knee extensors. Conclusions: The gender difference in muscle fatigue often observed during isometric tasks was diminished during fast dynamic contractions for upper and lower limb muscles. Muscle Nerve 48: 436–439, 2013
Factors associated with a better therapeutic effect of solifenacin in patients with overactive bladder syndrome
Authors: Hsiao Sheng‐Mou , Lin Ho‐Hsiung , Kuo Hann‐Chorng
Published: March 2013

Aims

To analyze the predictors of therapeutic success after solifenacin treatment.

Methods

Between January 2008 and December 2011, all patients with overactive bladder syndrome (OAB) who consecutively visited the urologic outpatient clinics of a medical center were prospectively enrolled. All enrolled patients received 5 mg solifenacin once a day for 12 weeks.

Results

Overall, 648 patients, 332 men, and 316 women, completed the 12‐week study. The overall success rate was 48.8%. The success rate for female patients was superior to that for male patients (55.4% vs. 42.5%, P < 0.001). The urgency severity scale (USS) score, daytime frequency, nocturia, voided volume, and bladder capacity were all improved after 12 weeks' treatment. Multivariate logistic regression analysis revealed that female gender, high USS score, high maximum flow rate (Qmax), and low postvoid residual volume (PVR) were all significant predictive factors for success after antimuscarinic treatment. USS score = 4 and Qmax ≥ 12 ml/sec were the most strongly predictive cutoff values for success, with receiver operating characteristic curve (ROC) areas of 0.70 (sensitivity = 66.8%, specificity = 66.0%) and 0.63 (sensitivity = 80.7%, specificity = 43.1%), respectively. PVR ≥70 ml was the most predictive cutoff value for failure, with a ROC area of 0.58 (sensitivity = 18.2%, specificity = 93.7%).

Conclusions

Female gender, high USS score, high Qmax, and low PVR were associated with better therapeutic efficacy. These findings could serve as an initial guide or assist in consultation regarding the treatment of OAB patients with antimuscarinics. Neurourol. Urodynam. 33:331–334, 2014. © 2013 Wiley Periodicals, Inc.
Conceptual framework for patient‐important treatment outcomes for pelvic organ prolapse
Authors: Sung Vivian W. , Rogers Rebecca G. , Barber Matthew D. , Clark Melissa A.
Published: March 2013

Aims

To develop a comprehensive conceptual framework representing the most important outcomes for women seeking treatment for pelvic organ prolapse (POP).

Methods

Twenty‐five women with POP were recruited and participated in four semi‐structured focus groups to refine and assess the content validity of a conceptual framework representing patient‐important outcomes for POP. Specifically, the focus groups addressed the following three aims: (1) to evaluate the content and appropriateness of domains in our framework; (2) to identify gaps in the framework; and (3) to determine the relative importance of our framework domains from the patient perspective. Sessions were transcribed, coded, and qualitatively and quantitatively analyzed using analytic induction and deductive analysis to identify themes and domains relevant to women with POP.

Results

Our focus groups confirmed the importance of vaginal bulge symptoms (discomfort, bother, and adaptation), and the overarching domains and subdomains of physical (physical function and participation), social (social function, relationships, and sexual function), and mental health (emotional distress, preoccupation, and body image). Patients ranked outcomes in the following order of importance: (1) the resolution of vaginal bulge symptoms, (2) improvement in physical function; (3) improvement in sexual function; (4) improvement in body image perception; and (5) improvement in social function.

Conclusions

We developed a conceptual framework for patient important outcomes of women seeking treatment for POP. This framework can improve the transparency and interpretation of POP study findings from the patient perspective. Vaginal bulge and its associated discomfort are most important for the definition of POP treatment success from the patient perspective. Neurourol. Urodynam. 33:414–419, 2014. © 2013 Wiley Periodicals, Inc.
Role of MRI in prostate cancer detection
Authors: Shukla‐Dave Amita , Hricak Hedvig
Published: March 2013

The standard approach for the detection of prostate cancer ‐‐ prostate‐specific antigen (PSA) screening followed by transrectal ultrasonography (TRUS)‐guided biopsy ‐‐ has low sensitivity and provides limited information about the true extent and aggressiveness of the cancer. Improved methods are needed to assess the extent and aggressiveness of the cancer and to identify patients who will benefit from therapy. In recent years, there has been tremendous development of acquisition and processing tools for physiological and metabolic MRI techniques which play a potential role in the detection, localization and characterization of prostate cancer, such as dynamic contrast‐enhanced MRI (DCE‐MRI), diffusion‐weighted MRI (DW‐MRI) and/or proton MR spectroscopic imaging (1H MRSI). The standard protocol for prostate MRI without the use of a contrast agent involves multi‐planar T1‐weighted MRI, T2‐weighted MRI and DW‐MRI. This review discusses the potential role of MRI in the detection of prostate cancer, specifically describing the status of MRI as a tool for guiding targeted prostate biopsies and for detecting cancer in the untreated and treated gland. In addition, future areas of MRI research are briefly discussed. Groups conducting clinical trials should consider the recommendations put forward by the European Consensus Meeting, which state that the minimum requirements for prostate MRI are T1‐weighted MRI, T2‐weighted MRI, DCE‐MRI (which involves the use of a contrast agent) and DW‐MRI with a pelvic phased‐array coil and propose the use of transperineal template mapping biopsies as the optimal reference standard. Copyright © 2013 John Wiley & Sons, Ltd.
Conducting polypyrrole‐coated banana fiber composites: Preparation and characterization
Authors: Merlini Claudia , Ramôa Sílvia D.A.S. , Barra Guilherme M.O.
Published: March 2013

In this study, conducting banana fibers (BF) were obtained through in situ oxidative polymerization of pyrrole (Py) on the BF surface using ferric chloride hexahydratate (FeCl3·6H2O) as an oxidant. Suitable reaction conditions are outlined for the polymerization of Py: oxidant/monomer molar ratio, Py concentration and polymerization time of 2/1, 0.05 mol.L−1 and 30 min, respectively. Under these conditions, high‐quality conducting fibers containing polyPy and BF (PPy‐BF) were obtained with an electrical resistivity as low as 0.54 Ω.cm. The PPy‐BF was blended with different concentrations of polyurethane (PU) by mixing the two components in a vacuum chamber and then applying compression molding. The electrical resistivity of composites with 25 wt% of PPy‐BF was around 1.8 × 105 Ωcm, which is approximately 108 times lower than that found for pure PU. Moreover, PU/PPy‐BF composites exhibited higher mechanical properties than pure PU and PU/PPy, indicating that these conducting fibers can also be used as reinforcement for polymer matrices. The properties of the PPy‐BF obtained by the method described herein open interesting possibilities for novel applications of electrically conducting fibers, from smart sensors to new conducting fillers that can be incorporated into several polymer matrixes to develop conducting polymer composites with good mechanical properties.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Fabrication of polymer/microwave‐reduced graphite oxide nanocomposites by ball‐milling assisted wet compounding
Authors: Long Jiang , Chen Guohua
Published: March 2013

Microwave‐induced reduction of graphite oxide (GO) is a promising method for rapid and scalable production of graphene. However, homogeneous incorporation of thus prepared graphene into polymer matrix is still a hard task. In this article, we present a ball‐milling assisted wet compounding method for the fabrications of microwave‐reduced GO (MRGO)/polymer composites. MRGO powders were added into a solution of polystyrene (PS) and then mechanically exfoliated in a stirring mill. Scanning electron microscopy and transmission electron microscopy investigations show that the graphene sheets have been homogeneously dispersed in the PS matrix. The composites show pronouncedly improved properties. The thermal degradation temperature of composites increased by 34°C with the addition of 5wt% MRGO in PS. Up to 76% improvement of storage modulus (at 30°C) is achieved by compounding with 10wt% MRGO.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Synthesis and characterization of PVA/YBCO nanocomposite for improvement of solar energy conversion
Authors: Shirbeeny W. , Hafez M. , Mahmoud Waleed E.
Published: March 2013

The development of nano‐metal oxide materials with unique optoelectronic properties such as highly solar energy absorption and generation of dense amount of electrons is one of the hottest topics now days. The incorporation of these nanomaterials into polymers results in an improvement of the properties of these polymers. Therefore, the understanding of their electronic properties is an essential demand to introduce these nanocomposites into service life. In this work, Yttrium barium copper oxide (YBCO) nanopowders with a uniform particle size of around 11 nm was prepared, sintered, and blended with polyvinyl alcohol (PVA) by casting technique. The characteristics of the structure and morphology of PVA/YBCO nanocomposite films are studied using X‐ray diffraction and transmission electron microscopy. The influence of YBCO nanoparticles on the thermal stability of PVA showed that the YBCO enhanced the thermal stability and reduced the rate of thermal degradation of PVA nanocomposites. Current–voltage behavior of PVA/YBCO nanocomposite films was measured at different temperatures. An explanation for the charge carrier concentration in the conduction band with the calculation of the barrier height, activation energy, and conversion and their dependence on temperature and applied field is presented.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Reduction of percolation threshold through double percolation in melt‐blended polycarbonate/acrylonitrile butadiene styrene/multiwall carbon nanotubes elastomer nanocomposites
Authors: Maiti Sandip , Shrivastava Nilesh K. , Khatua B.B.
Published: March 2013

We demonstrate a method that involves melt blending of polycarbonate (PC) and melt‐blended acrylonitrile butadiene styrene (ABS) with multiwall carbon nanotubes (MWCNTs) to prepare electrically conducting PC/MWCNT nanocomposites at significantly low MWCNT loading. The partial solubility of ABS in PC led to a selective dispersion of the MWCNTs in the ABS phase after melt‐blending PC and ABS. Thus, a sudden rise in electrical conductivity (∼108 orders of magnitude) of the nanocomposites was found at 0.328 vol% of MWCNT, which was explained in terms of double percolation phenomena. By optimizing the ratio of PC and the ABS–MWCNT mixture, an electrical conductivity of 5.58 × 10−5 and 7.23 × 10−3 S cm−1 was achieved in the nanocomposites with MWCNT loading as low as 0.458 and 1.188 vol%, respectively. Transmission electron microscopy revealed a good dispersion and distribution of the MWCNTs in the ABS phase, leading to the formation of continuous MWCNT network structure throughout the matrix even at very low MWCNT loading. Storage modulus and thermal stability of the PC were also increased by the presence of a small amount of MWCNTs in the nanocomposites.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Natural fiber blend—nylon 6 composites
Authors: Ozen Ertan , Kiziltas Alper , Kiziltas Esra Erbas , Gardner Douglas J.
Published: March 2013

In this study, engineering thermoplastic composites were prepared from natural fiber blend–filled nylon 6. Natural fiber blend from a mixture of kenaf, flax, and hemp fibers were added to nylon 6 using melt mixing to produce compounded pellets. The natural fibers/ nylon6 composites with varying concentrations of natural fibers (from 5 to 20 wt%) were prepared by injection molding. The tensile and flexural properties of the nylon 6 composites were increased significantly with the addition of the natural fiber blend. The maximum strength and modulus of elasticity for the nylon 6 composites were achieved at a natural fiber blend weight fraction of 20%. The Izod impact strength of composites decreased with the incorporation of natural fibers without any surface treatments and coupling agent. The melt flow index (MFI) also decreased with increasing natural fiber blend loading. The results of tensile and flexural modulus of elasticity (FMOE) are in accordance with the rheological data from the MFI measurements. The increase in the tensile and flexural properties indicated that efficient bonding occurred between the natural fibers and nylon 6. No fiber pullout was observed during the scanning electron microscopic analysis of the fracture surfaces. The higher mechanical results with lower density demonstrate that a natural fiber blend can be used as a sufficient reinforcing material for low‐cost, eco‐friendly composites in the automotive industry and in other applications such as the building and construction industries, packaging, consumer products, etc.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Dynamic mechanical analysis of elastic modulus development of dental composites
Authors: Jian Yu , He Yong , Zhao Liyan , Yang Wantai , Nie Jun
Published: March 2013

A method based on the compression mode of a dynamic mechanical analysis was first reported to measure the real‐time elastic modulus of dental composites during photopolymerization. By using this novel method, it was easy to investigate the real‐time development of mechanical property of dental materials. Because the modulus development was the consequence of photopolymerization, the modulus development was governed by the double‐bond conversion. High energy dose obtained by using high light intensity or long exposure time increased the “final” modulus because of the increase of conversion, but decreased the contribution of postpolymerization to the “final” modulus because of mobility limitation at high conversion. Moreover, the vitrification effect played the important role for the development of elastic modulus. The modulus significantly increased in the stage of vitrification.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
A glimpse of fear: Fast detection of threatening targets in visual search with brief stimulus durations
Authors: Soares Sandra C. , Esteves Francisco
Published: March 2013

Reliable detection of a threat based on temporally restricted information allows organisms to activate their defensive mechanisms. In the present study we investigated attentional efficiency for prototypical evolutionarily relevant stimuli, snakes (compared with spiders and mushrooms), during visual search conditions in which displays were presented for brief durations and under conditions of high perceptual load. Participants were exposed to a visual search paradigm in which the duration of the display varied between 150 and 300 ms. Perceptual load was manipulated using small, medium, and larger displays (4, 6, and 8 items, respectively). The results showed that fear stimuli, compared with neutral stimuli, were more accurately and quickly detected under both visually degraded conditions. The results also showed differences between the two categories of fear‐relevant stimuli (snakes and spiders) in their dependency on perceptual load manipulations. Snake targets were overall detected more accurately than spiders, with this snake advantage effect being more clear‐cut with many distracters (high load) than with few (low load). The results were interpreted in light of an evolutionary‐based theory (the snake detection theory), which posits that snakes are the prototypical predators of primates.
Introduction and empirical assessment of executive functioning as a predictor of job performance
Authors: Culbertson Satoris S. , Huffcutt Allen I. , Goebl Allen P.
Published: March 2013

The primary purposes of this study were (a) to introduce the concept of executive functioning (higher‐level cognitive processes which monitor events, actions, and outcomes) to the employee selection literature and (b) to provide an empirical assessment of executive functioning in relation to key selection variables. Two of the three main components of executive functioning (set shifting and inhibition) appear to have considerable potential for selection because of their unique nature (e.g., self‐directed, goal‐oriented) and because they appear to be only modestly associated with general mental ability. While our empirical results were inconsistent, there may be underlying reasons for this, such as the unstable nature of the retail job sector. We believe there is considerable justification for continued exploration of this unique and potentially promising construct, and identify a number of directions for future research.
Electrochemiluminescence biosensor for Ramos cells based on a nanostructured conducting polymer composite material (PICA‐MWNTs)
Authors: Nie Guangming , Bai Zhimin , Yu Wenying , Zhang Lin
Published: March 2013

A novel nanostructured conducting polymer (PICA‐MWNTs) is easily prepared by direct electrodeposition of indole‐6‐carboxylic acid (ICA) and carboxylic groups ended multiwalled carbon nanotubes (MWNTs) in acetonitrile in one step. The resulting PICA‐MWNTs composites with larger specific surface area and quite a few functionalized carboxylic acid groups are naturally integrated as a continuous uniform film on the electrode. CdSe quantum dots electrochemiluminescence biosensor with high sensitivity for detection of Ramos cells is fabricated based on PICA‐MWNTs. Coupled with nanoparticle‐amplification technnique, this sensor shows high sensitivity and good selectivity for Ramos cells with a low detection limit of 390 cells mL−1. This result provides an avenue for a simple and sensitive approach for detection of Ramos cells, which may have great potential in clinical applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2385–2392
Efficient terpolymerization of ethylene and styrene with α‐olefins by aryloxo‐modified half‐titanocene‐based catalysts and cocatalyst systems
Authors: Apisuk Wannida , Suzuki Naohiro , Kim Hyun Joon , Kim Dong Hyun , Kitiyanan Boonyarach , Nomura Kotohiro
Published: March 2013

Aryloxo‐modified half‐titanocenes, Cp′TiCl2(O‐2,6‐iPr2C6H3) [Cp′ = Cp* (1), tBuC5H4 (2)], catalyze terpolymerization of ethylene and styrene with α‐olefin (1‐hexene and 1‐decene) efficiently in the presence of cocatalyst, affording high‐molecular‐weight polymers with unimodal distributions (compositions). Efficient comonomer incorporations have been achieved by these catalysts. The content of each comonomer (α‐olefin, styrene, etc.) could be controlled by varying the comonomer concentration charged, and resonances ascribed to styrene and α‐olefin repeated insertion were negligible. The terpolymerization with p‐methylstyrene (p‐MS) in place of styrene also proceeded in the presence of [PhN(H)Me2][B(C6F5)4] and AliBu3 cocatalyst, and p‐MS was incorporated in an efficient matter, affording high‐molecular‐weight polymers with uniform molecular weight distributions. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2565–2574
Efficient ethylene/norbornene copolymerization by half‐titanocenes containing imidazolin‐2‐iminato ligands and MAO catalyst systems
Authors: Apisuk Wannida , Trambitas Alexandra G. , Kitiyanan Boonyarach , Tamm Matthias , Nomura Kotohiro
Published: March 2013

Ethylene copolymerizations with norbornene (NBE) using half‐titanocenes containing imidazolin‐2‐iminato ligands, Cp′TiCl2[1,3‐R2(CHN)2CN] [Cp′ = Cp (1), tBuC5H4 (2); R = tBu (a), 2,6‐iPr2C6H3 (b)], have been explored in the presence of methylaluminoxane (MAO) cocatalyst. Complex 1a exhibited remarkable catalytic activity with better NBE incorporation, affording high‐molecular‐weight copolymers with uniform molecular weight distributions, whereas the tert‐BuC5H4 analog (2a) showed low activity, and the resultant polymer prepared by the Cp‐2,6‐diisopropylphenyl analog (1b) possessed broad molecular weight distribution. The microstructure analysis of the poly(ethylene‐co‐NBE)s prepared by 1a suggests the formation of random copolymers including two and three NBE repeating units. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2575–2580
Synthesis and characterization of tridentate [O−N(H)X] titanium complexes and their applications in olefin polymerization
Authors: Wan Da‐Wei , Chen Zhou , Gao Yan‐Shan , Shen Qi , Sun Xiu‐Li , Tang Yong
Published: March 2013

A series of [O−N(H)X]TiCl3 complexes derived from (arylamino)methylene phenol are prepared. The molecular structures of the complexes are characterized by 1H NMR, 13C NMR, and X‐ray analysis. Upon activation with modified methylaluminoxane (MMAO), the titanium complexes display high thermal stability and single‐site like ethylene (co)polymerization behavior at the temperatures of up to 150 °C. 1‐Octene and 1‐octadencene prove suitable to be incorporated into polyethylene backbone at 110 °C and the highest activity of 1.89 × 106 g/mol(Ti)·h·atm can be achieved. The pendant group X has great influence on the catalytic behaviors of the complexes, and PPh2 proves to be the optimal group. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2495–2503
Co‐morbid mental health conditions in cancer patients at working age – prevalence, risk profiles, and care uptake
Authors: Singer S. , Szalai C. , Briest S. , Brown A. , Dietz A. , Einenkel J. , Jonas S. , Konnopka A. , Papsdorf K. , Langanke D. , Löbner M. , Schiefke F. , Stolzenburg J.‐U. , Weimann A. , Wirtz H. , König H. H. , Riedel‐Heller S.
Published: March 2013

Objective

This study examined the prevalence of mental health conditions in cancer patients, the role of socioeconomic position in relation to that, and the use of professional mental health care.

Methods

Prospective cohort with measurements at the beginning of inpatient treatment (baseline) and 3, 9, and 15 months after baseline using structured clinical interviews based on DSM‐IV, questionnaires, and medical records.

Results

At baseline, 149 out of 502 cancer patients (30%) were diagnosed with a mental health condition. Prevalence was associated with unemployment (odds ratio [OR] 2.0), fatigue (OR 1.9), and pain (OR 1.7).

Of those with mental health conditions, 9% saw a psychotherapist within 3 months of the diagnosis, 19% after 9 months, and 11% after 15 months. Mental health care use was higher in patients with children ≤18 years (OR 3.3) and somatic co‐morbidity (OR 2.6). There was no evidence for an effect of sex on the use of mental health care.

Conclusion

Few cancer patients with psychiatric disorders receive professional mental health care early enough. If patients are unemployed or if they suffer from fatigue or pain, special attention should be paid because the risk of having a mental health condition is increased in these patients. Copyright © 2013 John Wiley & Sons, Ltd.
The Mechanism of Plasma Destruction of Enalapril and Related Metabolites in Water
Authors: Magureanu Monica , Dobrin Daniela , Mandache Nicolae Bogdan , Bradu Corina , Medvedovici Andrei , Parvulescu Vasile I.
Published: March 2013

A pulsed dielectric barrier discharge was used for the decomposition of enalapril, its metabolite, enalaprilat, its degradation by‐product, diketopiperazine, as well as their combination, in aqueous solution. The discharge was generated at the interface between gas and the solution which flows as a film on the surface of the inner electrode of the plasma reactor. The degradation mechanism of the studied compounds and the temporal evolution of the reaction intermediates were established from LC–MS analysis. A wide variety of degradation by‐products were formed; at least six new derivatives, not mentioned in literature, were observed. However, most of these by‐products were subsequently degraded to small molecules. The mineralization degree, determined from TOC and COD measurements, was approximately 40%.

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CryoGRID 1.0: Permafrost Distribution in Norway estimated by a Spatial Numerical Model
Authors: Gisnås K. , Etzelmüller B. , Farbrot H. , Schuler T. V. , Westermann S.
Published: March 2013

CryoGRID 1.0 provides an equilibrium model of permafrost distribution in Norway at a spatial resolution of 1 km2. The approach was forced with gridded data on daily air temperature and snow cover. Ground thermal properties for different bedrock types and sediment covers were derived from surveys and geological maps to yield distributions of thermal conductivity, heat capacity and water content. The distribution of blockfields was derived from satellite images adapting a newly developed classification scheme. The model was evaluated using measured ground surface and ground temperatures, yielding a realistic description of the permafrost distribution in mainland Norway.

The model results show that permafrost underlies sites mainly with exposed bedrock or covered by coarse‐grained sediments, such as blockfields and coarse tills. In northern Norway, palsa mires are abundant and organic material and vegetation strongly influence the ground thermal regime. Modelling suggests that permafrost in equilibrium with the 1981–2010 climate presently underlies between 6.1 per cent and 6.4 per cent of the total area of mainland Norway, an area significantly smaller than that modelled for the Little Ice Age climate (14%). CryoGRID 1.0 was subsequently forced using output from a regional climate model for the 2071–2100 period, which suggests that severe permafrost degradation will occur, leaving permafrost beneath an area of just 0.2 per cent of mainland Norway. Copyright © 2013 John Wiley & Sons, Ltd.
Three dimensional structure of the anthrax toxin translocon–lethal factor complex by cryo‐electron microscopy
Authors: Gogol E. P. , Akkaladevi N. , Szerszen L. , Mukherjee S. , Chollet‐Hinton L. , Katayama H. , Pentelute B. L. , Collier R. J. , Fisher M. T.
Published: March 2013

We have visualized by cryo‐electron microscopy (cryo‐EM) the complex of the anthrax protective antigen (PA) translocon and the N‐terminal domain of anthrax lethal factor (LFN) inserted into a nanodisc model lipid bilayer. We have determined the structure of this complex at a nominal resolution of 16 Å by single‐particle analysis and three‐dimensional reconstruction. Consistent with our previous analysis of negatively stained unliganded PA, the translocon comprises a globular structure (cap) separated from the nanodisc bilayer by a narrow stalk that terminates in a transmembrane channel (incompletely distinguished in this reconstruction). The globular cap is larger than the unliganded PA pore, probably due to distortions introduced in the previous negatively stained structures. The cap exhibits larger, more distinct radial protrusions, previously identified with PA domain three, fitted by elements of the NMFF PA prepore crystal structure. The presence of LFN, though not distinguished due to the seven‐fold averaging used in the reconstruction, contributes to the distinct protrusions on the cap rim volume distal to the membrane. Furthermore, the lumen of the cap region is less resolved than the unliganded negatively stained PA, due to the low contrast obtained in our images of this specimen. Presence of the LFN extended helix and N terminal unstructured regions may also contribute to this additional internal density within the interior of the cap. Initial NMFF fitting of the cryoEM‐defined PA pore cap region positions the Phe clamp region of the PA pore translocon directly above an internal vestibule, consistent with its role in toxin translocation.
Explosibility of a urea dust sample
Authors: Thomas J. Kelly , Kirby David C. , Going John E.
Published: March 2013

The standard dust explosibility test is performed in a 20‐L vessel with either one or two 5 kJ pyrotechnic igniters. The dust is deemed to be explosible if the ratio of the maximum deflagration pressure to the initial pressure exceeds some threshold value. This type of test is widely accepted and used. However, marginal dusts may be “over driven” in the 20‐L standard test and yield a “false positive” result (i.e., indicate that the dust is explosible), even when such a dust is not capable of forming a dust cloud through which a flame would actually propagate any significant distance. This can be avoided by testing such dusts in a larger vessel, where the flame must propagate over a more reasonable distance in order to develop a maximum pressure sufficient to classify the dust as explosible. This article reports on urea dust testing where this type of result was obtained, but the approach taken in this work is applicable to other dusts as well. © 2013 American Institute of Chemical Engineers Process Saf Prog, 2013
First‐principles calculations of structural and electronic properties of pure and Tm2+‐doped SrCl2
Authors: Ma C.‐G. , Brik M. G.
Published: March 2013

The structural and electronic properties of pure and Tm2+‐doped SrCl2 have been studied in details using the hybrid density‐functional theory, as implemented in CRYSTAL09 code. The calculated local geometry structures of the doped site, electronic band structures, density of states, and Mulliken populations for the pure and doped crystals are analyzed and compared to reveal the changes induced by the impurity ion. Additionally, based on the optimized local structure, the 4f13 and 4f125d energy levels of Tm2+ ions in SrCl2 are calculated by employing the exchange charge model of the semi‐empirical crystal‐field theory. The simulated 4f–5d transition optical spectrum of Tm2+ ions in SrCl2 shows good agreement with the corresponding experimental result.
Corrugated Box Compression—A Literature Survey
Authors: Frank Benjamin
Published: March 2013

The past 130+ years of research into the production of corrugated packaging has produced a tremendous wealth of information about the structural dynamics of corrugated boxes in use and in failure. Most of the studies in this area were published in the journals of the paper industry. However, much of the current work on corrugated fiberboard packaging now comes from individuals with a focus on corrugated packaging as a whole rather than on the corrugated paper or structures that comprise the packaging material. Because of the difficulty in accessing or identifying some of the previous art, more recent studies may tread ground well covered by others decades earlier. This review focuses on the process of box compression and the utility of box compression testing, bringing previous work back to the fore to provide useful background for current studies. It examines the conditioning and testing process in detail, discusses the state of the art in compression estimation, and explores various parameters that affect box compression strength that are not captured in most current industry models. It also looks at how box compression results are related to field performance of boxes in unit loads. In the process, it identifies many areas for fruitful new research. Copyright © 2013 John Wiley & Sons, Ltd.