bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemically stable polyphenylene ether microcapsules prepared using a facile method for the self‐healing of polymers
Authors: Wu Shenmei , Yuan Li , Zhang Ying , Gu Aijuan , Zhang Yi , Liang Guozheng
Published: March 2016

Chemically stable polyphenylene ether (PPO) microcapsules (MCs) filled with epoxy resins (PPO‐EP MCs) were prepared using low‐molecular‐weight PPO with vinyl end‐groups as shell wall and epoxy resins as core material using an oil‐in‐water emulsion solvent evaporation method. This method for synthesizing MCs with PPO shell walls is simple, convenient and novel, which can avoid the influence of processing parameters on the chemical stability of the epoxy resin core material. The resulting PPO‐EP MCs exhibit good chemical stability below 255 °C mainly owing to the absence of a polymerization catalyst of the epoxy resins. The initial thermal decomposition temperature of the MCs is about 275 °C. The MCs were embedded in a 4,4′‐bismaleimidodiphenylmethane/O,O′‐diallylbisphenol A (BMI/BA) thermosetting resin system. When processed at high temperature (up to 220 °C), the microencapsulated epoxy resins could be released from the fractured MCs to matrix crack surfaces and bond the crack surfaces. An amount of 8 wt% MCs restored 91 and 112% of the original fracture toughness of the BMI/BA matrix when heated at 220 °C/2 h and 80 °C/1 h + 220 °C/2 h, respectively. The MCs only slightly decreased the thermal property of the matrix. © 2016 Society of Chemical Industry
High‐sensitivity HLA class I peptidome analysis enables a precise definition of peptide motifs and the identification of peptides from cell lines and patients’ sera
Authors: Ritz Danilo , Gloger Andreas , Weide Benjamin , Garbe Claus , Neri Dario , Fugmann Tim
Published: March 2016

The characterization of peptides bound to human leukocyte antigen (HLA) class I is of fundamental importance for understanding CD8+ T cell‐driven immunological processes and for the development of immunomodulatory therapeutic strategies. However, until now, the mass spectrometric analysis of HLA‐bound peptides has typically required billions of cells, still resulting in relatively few high‐confidence peptide identifications. Capitalizing on the recent developments in mass spectrometry and bioinformatics, we have implemented a methodology for the efficient recovery of acid‐eluted HLA peptides after purification with the pan‐reactive antibody W6/32 and have identified a total of 27 862 unique peptides with high confidence (1% false discovery rate) from five human cancer cell lines. More than 93% of the identified peptides were eight to 11 amino acids in length and contained signatures that were in excellent agreement with published HLA binding motifs. Furthermore, by purifying soluble HLA class I complexes (sHLA) from sera of melanoma patients, up to 972 high‐confidence peptides could be identified, including melanoma‐associated antigens already described in the literature. Knowledge of the HLA class I peptidome should facilitate multiplex tetramer technology‐based characterization of T cells, and allow the development of patient selection, stratification and immunomodulatory therapeutic strategies.
Double responsive copolymer hydrogels prepared by frontal polymerization
Authors: Nuvoli Luca , Sanna Davide , Alzari Valeria , Nuvoli Daniele , Sanna Vanna , Malfatti Luca , Mariani Alberto
Published: March 2016

Frontal polymerization was successfully used to synthesize copolymer hydrogels of poly(N‐vinylcaprolactam‐co‐itaconic acid). All materials were characterized by response to stimuli (pH and/or temperature), depending on the itaconic acid content. Namely, relatively low amounts of this latter were found to be crucial for determining the degree of swelling. In particular, hydrogels behave differently if swollen at pH values that are higher or lower of 7–8, and exhibit temperature response as well (lower critical solution temperature at ca. 30 °C), which makes these materials potentially interesting for biomedical applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2166–2170
Dextran oxidized by a malaprade reaction shows main chain scission through a maillard reaction triggered by schiff base formation between aldehydes and amines
Authors: Chimpibul Wichchulada , Nagashima Toshio , Hayashi Fumiaki , Nakajima Naoki , Hyon Suong‐Hyu , Matsumura Kazuaki
Published: March 2016

Although periodate‐oxidized dextran is widely used in biomedical applications, the degradation mechanism of oxidized dextran has not yet been elucidated. Herein, we propose a novel main chain scission mechanism of oxidized dextran triggered by reaction with amine. NMR analysis revealed four hemiacetal substructures during oxidation by periodate. Kinetic analysis showed that the degradation time constant of the C3‐removed substructure and increasing time constant of the reducing end protons are consistent with the decrease in molecular weight determined by gel permeation chromatography. A methylene group is generated at the same time constant of degradation, indicating that oxidized dextran degradation proceeds via a Maillard reaction. Oxidized dextran does not degrade in saline solution without reactive amine species. Thus, we conclude that oxidized dextran is degraded in the main chain via Schiff base formation through a Maillard reaction, depending on the oxidation ratio and amino acid concentration. These findings help to elucidate the reaction mechanism of polysaccharide degradation and develop novel biodegradable polysaccharide materials for biomedical applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2254–2260
Reversible shape‐shifting in polymeric materials
Authors: Zhou Jing , Sheiko Sergei S.
Published: March 2016

In recent years, significant progress has been made in polymeric materials, which alter shape upon external stimuli, suggesting potential applications in robotics, biomedical engineering, and optical devices. These stimuli‐responsive materials may be categorized into two classes: (i) shape‐changing materials in which a specific type of shape‐shifting is encoded in the original material structure and (ii) shape‐memory materials, which do not possess any predetermined shape‐shifting as prepared, yet allow programming of complex shape transformations on demand. While shape alterations in shape‐changing materials are intrinsically reversible, shape memory is usually a one‐way transformation from a metastable (programmed) to an equilibrium (original) state. Recently, different principles for both one‐way reversible and two‐way reversible shape memory have been developed. These offer a powerful combination of reversibility and programmability, which significantly expands the range of potential applications. The goal of this review is to highlight recent developments in reversible shape‐shifting by introducing novel mechanisms, materials, and applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1365–1380
Savoring moderates the association between cancer‐specific physical symptoms and depressive symptoms
Authors: Hou Wai Kai , Lau Kam Man , Ng Sin Man , Cheng Ashley Chi Kin , Shum Tracy Chui Yu , Cheng Sheung‐tak , Cheung Hester Yui Shan
Published: March 2016

Background

This study investigated the associations of savoring with cancer‐specific physical symptoms, psychological distress, and psychological well‐being and the moderating effect of savoring in the associations between physical symptoms and psychological outcomes among cancer patients.

Methods

A total of 263 Chinese adults recently diagnosed with cancer (mean time since diagnosis = 43.72 days, SD = 38.20) were recruited and administered a questionnaire assessing cancer‐specific physical symptoms, perceived capability of savoring the moment, psychological distress, and psychological well‐being within six months following diagnosis.

Results

Structural equation modeling revealed significant associations of savoring with physical symptoms and psychological distress and well‐being (β = −0.41–0.54, p < 0.0001). Savoring significantly moderated the association between physical symptoms and depressive symptoms. Simple slope tests revealed that the association was not significant at higher levels of savoring (estimate = 0.15, z = 0.49, p = 0.62) whereas it was stronger at lower (estimate = 1.11, z = 4.81, p < 0.001) and medium (estimate = 0.63, z = 3.04, p < 0.01) levels of savoring. The effects of demographic and medical covariates were controlled for in all models.

Conclusions

The findings suggest that savoring is positively associated with physical and psychological functioning among people with cancer. The link between physical symptoms and depressive symptoms could be exacerbated at lower levels of savoring. Fostering savoring beliefs and practices could be a significant psychological component of symptom management among cancer patients. Copyright © 2016 John Wiley & Sons, Ltd.
MiR‐301a regulates E‐cadherin expression and is predictive of prostate cancer recurrence
Authors: Nam Robert K. , Benatar Tania , Wallis Christopher J. D. , Amemiya Yutaka , Yang Wenyi , Garbens Alaina , Naeim Magda , Sherman Christopher , Sugar Linda , Seth Arun
Published: March 2016

BACKGROUND

MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression post‐transcriptionally. Dysregulation of miRNA has been implicated in the development and progression of prostate cancer. Through next generation miRNA sequencing, we recently identified a panel of five miRNAs associated with prostate cancer recurrence and metastasis. Of the five miRNAs, miR‐301a had the strongest association with prostate cancer recurrence. Overexpression of miR‐301a in prostate cancer cells, PC3, and LNCaP resulted in increased growth both in vitro and in xenografted tumors. We therefore sought to examine its role in prostate carcinogenesis in greater detail.

METHODS

We examined the effect of miR‐301a expression on biochemical recurrence and metastasis among 585 men treated with radical prostatectomy for prostate cancer. We examined the mechanism of growth deregulation by miR‐301a in prostate cancer cells using analysis of the miRome of prostate cancer cell lines, quantitative PCR, and Western blotting.

RESULTS

High levels of miR‐301a (above the median) were associated with an increased risk of biochemical recurrence (adjusted hazard ratio [aHR] 1.42, 95% confidence interval (CI) 1.06–1.90, P = 0.002) but not of metastasis (aHR 0.84, 95%CI 0.41–1.70, P = 0.6) after adjustment for known prognostic factors. RNA transcriptome sequencing analysis of miR‐301a overexpressing prostate cancer cell lines identified the tumor suppressor p63 as a potential direct miR‐301a target. Transcriptome sequencing, qPCR and Western blotting showed that miR‐301a induced epithelial–mesenchymal transition (EMT) in prostate cancer cells through a pathway initiated by p63 inhibition. Luciferase assay verified p63 as a direct target of miR‐301a. Loss of p63 resulted in miR‐205 downregulation, releasing Zeb1 and Zeb2 from inhibition, culminating in Zeb1/Zeb2 suppression of E‐cadherin. This pathway of growth alteration mediated by miR‐301a upregulation was shown to be valid in prostate cancer cell lines and patient‐derived tumors.

CONCLUSIONS

These data indicate that miR‐301a functions as an oncogene in prostate cancer by directly targeting the p63 tumor suppressor leading to loss of E‐cadherin and EMT. Hence, miR‐301a may serve as a novel biomarker in prostate cancer as well as a therapeutic target for prostate cancer management. Prostate 76:869–884, 2016. © 2016 Wiley Periodicals, Inc.
Hole‐mobility limits for the Zn(OC)2 organic semiconductor obtained by SCLC and field‐effect measurements
Authors: Landi Giovanni , Tunc Ali Veysel , De Sio Antonietta , Parisi Jürgen , Neitzert Heinz‐Christoph
Published: March 2016

The hole mobility of a semiconducting film with a new type of small molecule has been determined by electrical characterization with two different device geometries. The small molecule, namely Zn(OC)2, consists of oxadiazole groups (O), that act as electron conductor and blue emitter, and carbazole groups (C), that are hole conductors, which are arranged around a central Zn‐atom. This disordered organic material has in principal ambipolar conduction properties. In both the organic devices investigated, that is, a vertical diode and a bottom‐gate organic field effect transistor, the transport is dominated by holes. In the diode structure, the charge carrier transport shows a dependence from the electric field with a space charge limited current characteristic. The hole mobility value is several orders of magnitude higher as compared to the one extracted from the characteristics of the organic transistor. This large difference in the charge carrier transport properties for the two different device configurations is due to the strong influence of the dielectric/semiconductor interface which degrades the hole transport in the organic field effect transistor.
New insight into the modulated photocurrent technique using 2D full numerical simulations
Authors: Lachaume Raphaël , Longeaud Christophe , Kleider Jean‐Paul
Published: March 2016

The modulated photocurrent technique has been used for a few decades now to provide information on the localized density of states (DOS) in semiconductor thin films. In previous studies, a simplified analytical treatment has been performed in 1D to derive equations that one has been using to reconstruct the DOS located near the majority carrier band. In these former studies, all the physical quantities were considered as constant within the sample depth, however, we know that it is not the case especially in the presence of a strong gradient of photogeneration in some materials. In this paper, for the first time, we show results of 2D simulations of the modulated photocurrent (MPC) experiment in order to study the effect of vertical photogeneration inhomogeneity on the MPC and to discuss the validity of the 1D assumption in more realistic cases. Thanks to these 2D simulations, new insight is gained in the understanding of the MPC experiment. Indeed, we show that we can explain and reproduce some of the experimental behaviors that the 1D theory failed to predict. Hydrogenated amorphous silicon (a‐Si:H) is taken as a reference material for demonstration purposes, but this 2D approach can also be extended to other semiconductor materials and other types of inhomogeneities.
Hydrogels with incorporated graphene oxide as light‐addressable actuator materials for cell culture environments in lab‐on‐chip systems
Authors: Breuer L. , Raue M. , Strobel M. , Mang T. , Schöning M. J. , Thoelen R. , Wagner T.
Published: March 2016

Abstractauthoren Graphene oxide (GO) nanoparticles were incorporated in temperature‐sensitive Poly(N‐isopropylacrylamide) (PNIPAAm) hydrogels. The nanoparticles increase the light absorption and convert light energy into heat efficiently. Thus, the hydrogels with GO can be stimulated spatially resolved by illumination as it was demonstrated by IR thermography. The temporal progression of the temperature maximum was detected for different concentrations of GO within the polymer network. Furthermore, the compatibility of PNIPAAm hydrogels with GO and cell cultures was investigated. For this purpose, culture medium was incubated with hydrogels containing GO and the viability and morphology of chinese hamster ovary (CHO) cells was examined after several days of culturing in presence of this medium.
Optimisation and design of PV modules for the application on bus roof‐top and system integration for solar cooling
Authors: Demircioğlu Olgu , Es Fırat , Hande Çiftpınar Emine , Zeybek Akın , Tuncer Cahit , Turan Raşit
Published: March 2016

In this study, an external electrical cooling unit powered by PV modules was installed on the roof‐top of a bus to keep cooled interior atmosphere at a certain temperature level during the journey breaks. All solar cells used in this project were fabricated by Center for Solar Energy Research and Applications (GUNAM) and; then, integrated onto a bus roof together with MAN Turkey A.Ş. For integration of PV modules onto roof of bus, a reliable and commercially applicable method has been developed. Following integration, illumination level on the bus in summer season was measured to investigate the shadow effect on the bus roof while touring in the city. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical modeling and simulation of ZnO nanowire devices for energy harvesting
Authors: Serairi Linda , Yu Dapeng , Leprince‐Wang Yamin
Published: March 2016

Duo to their multifunctional properties, the piezoelectric ZnO nanowires are of great interest in many applications such as the energy harvesting. In this work, a numerical modelling based on the finite element method was performed to study the potential distribution inside the ZnO nanowire and the impact of the geometric parameters on the generated piezopotential both in bending and compression deformation. In this context, a nanowire discharge behavioural study was carried out in order to obtain an analytic expression which connects the piezopotential and nanowire geometrical parameters in the bending deformation. Furthermore, a heuristic algorithm Particle Swarm Optimization (PSO) has been used in order to improve the electromechanical performance of ZnO nanowire based nanogenerator. It is fount that under the same order of force applied on a nanowire, the compression mode results in a piezopotential 9 times larger than that in the bending deformation. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tamm plasmon polaritons in the visible spectral region and its optical properties in ZnSe‐based microcavities
Authors: Shaid‐Ur Rahman S. K. , Sebald Kathrin , Gutowski Jürgen , Klein Thorsten , Klembt Sebastian , Kruse Carsten , Hommel Detlef
Published: March 2016

We report on the formation of Tamm plasmon (TP) modes in the visible spectral region at the interface between a Ag film and a ZnSe‐based distributed Bragg reflector (DBR). The tuning of the TP eigenenergies within the stop‐band in dependence on the DBR top layer thickness is investigated by micro‐reflectivity measurements. The experimental findings are compared with calculations using the transfer matrix method. The latter calculations show that strong coupling can be achieved between quantum well (QW) excitons and the TP modes. In addition, the Rabi‐splitting energy can be enhanced in a simple TP structure by increasing the number of QWs inside the top layer of the DBR.

When a metal layer is deposited on a cold MC sample, micro‐reflectivity spectra show a blue shift of the cavity resonance. The TP modes are likewise observed in the same MC sample when reducing the top layer thickness of the DBR. This shift of cavity resonance and formation of TP mode are in good agreement with calculations. These results are rather promising in order to realize a spatial confinement of the polaritons by utilizing metal strips. Such channeling of polaritons opens the way to practical demonstration of exciton‐polariton integrated circuits. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A comparative study of the gas sensing properties of hierarchical ZnO nanostructures
Authors: Capochichi‐Gnambodoe Martine , Habba Yamina Ghozlane , Leprince‐Wang Yamin
Published: March 2016

Two types of ZnO nanostructure have been fabricated to make a comparative study on their gas sensing performance: the conventional ZnO nanowire arrays were synthesized by hydrothermal method and the hierarchical ZnO nanowires/nanofibers nanostructures were prepared through a combination of the hydrothermal and electrospinning methods. Field emission scanning electron microscopy study showed a quiet homogeneous morphology both for both nanostructures. Three kinds of commonly used gases, such as ethanol, acetone and ammonia were chosen for ZnO nanostructure gas sensing property study. The UV‐Visible spectroscopy measurements showed a higher detection sensitivity of ZnO NWs for ammonia compared to ethanol and acetone, and an enhanced sensing performance for the hierarchical nano‐ structure, which has a higher surface to volume ratio. On the other hand, the enhancement was more obviously in the case of ethanol sensing. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of source transport rate upon fractions of Mg and Se in Zn1‐xMgxSeyTe1–y layers grown by metalorganic vapor phase epitaxy
Authors: Saito Katsuhiko , Abiru Masakatsu , Mori Eiichiro , Araki Yasuhiro , Tanaka Daichi , Tanaka Tooru , Guo Qixin , Nishio Mitsuhiro
Published: March 2016

The growth of undoped Zn1–xMgx Sey Te1–y layers on (100) ZnTe substrates by metalorganic vapor phase epitaxy has been carried out. The fractions of Mg and Se, Raman property and surface roughness have been characterized as a function of bis‐methylcyclopentadienyl‐magnesium ((MeCp)2Mg) or diethylselenide (DESe) transport rates. It has been demonstrated that the Mg and Se fractions in Zn1–xMgx Sey Te1–y layer can be controlled successfully by these source transport rates. Furthermore, the behaviors of two Raman peaks related to ZnSeTe‐like longitudinal optical phonon mode and MgSeTe‐like one have been clarified for some Mg and Se fractions in Zn1–xMgx Sey Te1–y layers. It has been shown by varying (MeCp)2Mg or DESe transport rates that Zn1‐xMgx Sey Te1–y layer nearly‐lattice‐matched to ZnTe substrate shows low surface roughness. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recent advances in robot‐assisted head and neck surgery
Authors: Friedrich Daniel T. , Scheithauer Marc O. , Greve Jens , Hoffmann Thomas K. , Schuler Patrick J.
Published: March 2016

Objective

This article reviews current clinical applications and experimental developments for robotic surgery in the head and neck with special focus on financial challenges, current clinical trials, and the controversial aspect of haptic and tactile feedback.

Data sources

Literature was screened using the pubmed library. Information on clinical trials was excerpted from the National Institute of Health database. Additional data on experimental developments were gathered by personal communication.

Results

A steep increase in clinical applications for robotic surgery in the head and neck is determined as possible indications extend. Clinical trials are mostly non‐randomized. A wide range of new robotic systems are expected to come into clinical use in the near future.

Conclusion

As head and neck surgeons become more familiar with robotic surgery some patients evidently benefit from new technologies. Increased competition between the systems will certainly drive technological improvement and decrease the financial burden. Copyright © 2016 John Wiley & Sons, Ltd.
Fish and Benthic Macroinvertebrate Assemblage Response to Removal of a Partially Breached Lowhead Dam
Authors: Gillette D. P. , Daniel K. , Redd C.
Published: March 2016

Dam removal is an increasingly common restoration technique in lotic ecosystems. Potential dam removal benefits include improved aquatic organism passage, restoration of natural flow dynamics and a general improvement in habitat for native species. However, understanding potential dam removal outcomes requires data on ecosystem response in a wide variety of settings. We evaluated fish and benthic macroinvertebrate response to removal of the Spruce Pine dam in western North Carolina, USA. This dam was partially breached prior to removal, and impounded a coolwater river, both scenarios under which dam removal has been under‐studied. Post‐removal shifts in fish and benthic macroinvertebrate assemblages did not occur, suggesting that previously documented patterns of assemblage change in response to dam removal, particularly in the area upstream from the dam, are not universal, and may depend upon factors such as river gradient and water temperature, and the available species pool. Such information can aid managers in identifying conditions under which an expectation of significant instream habitat improvement in response to dam removal may not be warranted. Copyright © 2016 John Wiley & Sons, Ltd.
Morphological and nanomechanical changes in mechanosensitive endothelial cells induced by colloidal AFM probes
Authors: Targosz‐Korecka Marta , Malek‐Zietek Katarzyna E. , Brzezinka Grzegorz D. , Jaglarz Magdalena
Published: March 2016

Mechanotransduction is one of the main properties of endothelial cells (ECs) phenotype. Hemodynamic forces like flow‐generated endothelial shear stress play a fundamental role in ECs cytoskeletal remodeling and activate signaling cascades in ECs. AFM methods are widely used to characterize morphology as well as mechanical properties of cells. In both cases AFM probes directly interact with cell surface exerting mechanical forces on the cellular membrane, which in turn may stimulate mechanosensitive receptors present in EC. This article presents examples of how the colloidal AFM probes influence ECs during multiple scans. The results revealed that multiple scans of the ECs significantly influenced the morphology and elasticity of cells. Moreover, changes in the cell shape and mechanical properties were dependent on the scan direction (across or along the main axis of the cell). Multiple scans with a colloidal probe leaded to reorientation of the cell main axis and this effect was similar to the action of the shear stress induced by flow conditions. Furthermore, the correlation between the tip‐induced modification of the cell properties and the remodeling of the cell's glycocalyx was observed. SCANNING 38:654–664, 2016. © 2016 Wiley Periodicals, Inc.
Insights Into the Diversity of Attitudes Concerning Evolution and Creation: A Multidimensional Approach
Authors: KONNEMANN CHRISTIANE , ASSHOFF ROMAN , HAMMANN MARCUS
Published: March 2016

The main aim of this paper is to describe high school students’ attitudes concerning evolution and creation, with a focus on (1) attitudes toward evolutionary theory, (2) attitudes toward the Biblical accounts of creation, (3) creationist beliefs, and (4) scientistic beliefs. Latent class analyses revealed seven attitude profiles in a sample of 1672 German high school students. In contrast with the prevailing focus on creationism in science education research, a scientistic attitude profile (22%) rather than a creationist attitude profile (4%) characterized the largest group in this sample. The remaining five profiles account for three‐fourths of the sample and describe a range of different positions, that is, noncreationist and nonscientistic positions. Moreover, the groups of students who belonged to different attitude profiles differed significantly in terms of further variables: (a) perception of conflict between science and theology, (b) attitudes toward science, (c) attitudes toward religion, (d) understanding of the nature of science, and (e) understanding of the nature of Christian theology. The benefit of the presented approach is discussed in the context of previous studies that focused on the acceptance of evolutionary theory. Because we found evidence for a wide variety of attitudes, implications for teaching and learning evolution are discussed.
Comparative study of Au–Sn and Sn–Ag–Cu as die‐attach materials for power electronics applications
Authors: Lee Byung‐Suk , Lee Chang‐Woo , Yoon Jeong‐Won
Published: March 2016

A comparative study of Sn–3.0Ag–0.5Cu (SAC305) and Au–20Sn solders as die‐attach materials for high‐temperature power electronic applications was performed. The solid‐state interfacial reactions of SAC305 and Au–20Sn solders with a Ni‐plated Si chip and a direct‐bonded‐copper substrate, as well as the growth of interfacial intermetallic compound layers and interfacial stability, were investigated and compared during aging at 150 and 200 °C for up to 2000 h. The SAC305 solder exhibited a higher interfacial intermetallic compound growth rate and a higher consumption rate of the Ni layer than the Au–20Sn solder. The Au–20Sn solder had a superior interfacial stability for high‐temperature power electronic applications. Copyright © 2016 John Wiley & Sons, Ltd.
Electrodeposition of dendritic gold/silver nanaoparticles on disposable screen‐printed carbon electrode and its application of 4‐mercaptopyridine in in situ electrochemical surface‐enhanced Raman scattering
Authors: Teng Yuanjie , Ding Guocheng , Liu Wenhan , Liu Jiangmei , Nie Yonghui , Li Pan
Published: March 2016

Column electrodes pretreated through oxidation–reduction cycles were traditionally used in electrochemical surface‐enhanced Raman scattering (SERS). In this study, a disposable screen‐printed carbon electrode was introduced into in situ electrochemical SERS through the electrodeposition of dendritic gold/silver nanoparticles (Au/AgNPs) onto the surface of the carbon working electrode to induce the SERS enhancement effect on the electrode. Scanning electron microscopy images showed that dendritic Au/AgNPs nanostructures could be fabricated under appropriate electrodeposition conditions and could present a minimum SERS factor of 4.25 × 105. Furthermore, the absorbed behavior of 4‐mercaptopyridine was investigated under different potentials. The adsorption configuration was inferred to transform from ‘vertical’ to ‘lying‐flat’. The proposed new electrode combined with a portable Raman spectrometer could be useful in the identifying products or intermediates during electrochemical synthesis or electrochemical catalysis in in situ electrochemical SERS. Copyright © 2016 John Wiley & Sons, Ltd.
Determination of phosphoryl‐oligosaccharides obtained from Canna edulis Ker starch
Authors: Liu Jianhua , Li Hu , Wu Jinhong , Xie Fan , Zhang Juan , Wang Zhengwu
Published: March 2016

Phosphoryl oligosaccharides (POs) are a new type of functional oligosaccharide that promote the absorption of calcium. Canna edulis Ker (edible canna) starch contains a small amount of phosphorus and may be a source in the production of POs. Herein, the POs fraction was separated from Canna edulis Ker starch for the first time using enzymatic reactions that produce isomalto‐oligosaccharides (IMOs). Fourier transform infrared (FT‐IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and high‐performance anion exchange chromatography (HPAEC) were used to determine the presence and composition of the isolated POs. The POs that were obtained from Canna edulis Ker starch were mainly composed of phosphoryl maltotriose, maltotetraose, maltopentaose, maltohexaose, and maltoheptaose. These findings provide new insight into the simultaneous production of IMOs and POs from Canna edulis Ker starch by enzymatic reaction.
Effects of amylose/amylopectin starch on starch‐based superabsorbent polymers prepared by γ‐radiation
Authors: Zhang Ya‐nan , Xu Shi‐ai
Published: March 2016

Biodegradable superabsorbent polymers (SAPs) were synthesized in this study by graft copolymerization of acrylic acid onto amylose and amylopectin using N,N′‐methylenebisacrylamide as a cross‐linker, initiated by an initiator (potassium persulfate) and γ‐ray radiation, respectively. The structures of the resultant amylose‐graft‐poly(acrylic acid) (amylose‐g‐PAA) and amylopectin‐graft‐poly(acrylic acid) (amylopectin‐g‐PAA) SAPs were characterized by Fourier transform infrared (FTIR) spectroscopy, solid‐state 13C nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetric analysis (TGA). The main purpose of this study is to investigate the effects of the two initiation modes and chain structures of starches on the grafting ratios (GR) and properties of these amylose‐g‐PAA and amylopectin‐g‐PAA SAPs. The results show that SAPs prepared by γ‐radiation have higher water absorption and GR than SAPs prepared by the initiator. In addition, amylose‐g‐PAA SAPs have higher water absorption and GR than amylopectin‐g‐PAA SAPs. The optimum water absorption is 530 g/g for amylose‐g‐PAA SAPs and 355 g/g for amylopectin‐g‐PAA SAPs, respectively. It is concluded that γ‐radiation is more time‐saving, energy‐saving, and efficient than the initiator.
Production of raw starch degrading enzyme by the thermophilic filamentous bacterium Laceyella sacchari LP175 and its application for ethanol production from dried cassava chips
Authors: Lomthong Thanasak , Lertwattanasakul Noppon , Kitpreechavanich Vichien
Published: March 2016

Physical factors that enhanced the production of raw starch degrading enzyme by a thermophilic filamentous bacterium, Laceyella sacchari LP175 in a 3 L airlift fermenter, were optimized at a pH of 6.5, a temperature of 45°C, and an aeration rate of 0.5 vvm using a central composite design. This yielded 278 U/mL, at 36 h cultivation, an increase in enzyme production and productivity of 1.53‐ and 2.04‐fold, respectively, as compared with a shaking flask cultivation. Raw starch degrading enzyme produced by L. sacchari LP175 with commercial glucoamylase synergistically enhanced the hydrolysis of 300 g/L dried cassava chips (71% starch content) to 157 g/L reducing sugars, equivalent to 66.3% hydrolysis at pH 6.5 and 50°C for 12 h. The comparative study on bioethanol production in a non‐sterile system from dried cassava chip by three different processes; the maximum production, 90.9 g/L (88% theoretical yield), was obtained by modified simultaneous saccharification and fermentation at 50°C for 6 h and subsequent fermentation by the thermotolerant Kluyveromyces marxianus DMKU‐KS07 at 42°C within 18 h with the highest productivity of 3.79 g/L/h. The other processes tested – separate hydrolysis and fermentation and simultaneous saccharification and fermentation – yielded 83 and 51.6 g/L of ethanol, respectively.
Multiple Subsets of Brain Tumor Initiating Cells Coexist in Glioblastoma
Authors: Rennert Robert C. , Achrol Achal S. , Januszyk Michael , Kahn Suzana A. , Liu Tiffany T. , Liu Yi , Sahoo Debashis , Rodrigues Melanie , Maan Zeshaan N. , Wong Victor W. , Cheshier Samuel H. , Chang Steven D. , Steinberg Gary K. , Harsh Griffith R. , Gurtner Geoffrey C.
Published: March 2016

Brain tumor-initiating cells (BTICs) are self-renewing multipotent cells critical for tumor maintenance and growth. Using single-cell microfluidic profiling, we identified multiple subpopulations of BTICs coexisting in human glioblastoma, characterized by distinct surface marker expression and single-cell molecular profiles relating to divergent bulk tissue molecular subtypes. These data suggest BTIC subpopulation heterogeneity as an underlying source of intra-tumoral bulk tissue molecular heterogeneity, and will support future studies into BTIC subpopulation-specific therapies.
Vav1 Regulates Mesenchymal Stem Cell Differentiation Decision Between Adipocyte and Chondrocyte via Sirt1
Authors: Qu Peng , Wang Lizhen , Min Yongfen , McKennett Lois , Keller Jonathan R. , Lin P. Charles
Published: March 2016

Mesenchymal stem cells (MSCs) are multipotent stromal cells residing in the bone marrow. MSCs have the potential to differentiate to adipocytes, chondrocytes, and other types of cells. In this study, we investigated the molecular mechanism that controls MSC cell fate decisions for differentiation. We found that Vav1, a guanine nucleotide exchange factor for Rho GTPase, was highly expressed in MSCs. Interestingly, loss of Vav1 in MSCs led to spontaneous adipogenic but impaired chondrogenic differentiation, and accordingly Vav1 null mice displayed an increase in fat content and a decrease in cartilage. Conversely, ectopic expression of Vav1 in MSCs reversed this phenotype, and led to enhanced MSC differentiation into chondrocyte but retarded adipogenesis. Mechanistically, loss of Vav1 reduced the level of Sirt1, which was responsible for an increase of acetylated PPARγ. As acetylation activates PPARγ, it increased C/EBPα expression and promoted adipogenesis. On the other hand, loss of Vav1 resulted in an increase of acetylated Sox9, a target of Sirt1. As acetylation represses Sox9 activity, it led to a dramatic reduction of collagen 2α1, a key regulator in chondrocyte differentiation. Finally, we found that Vav1 regulates Sirt1 in MSCs through Creb. Together this study reveals a novel function of Vav1 in regulating MSC cell fate decisions for differentiation through Sirt1. Sirt1 deacetylates PPARγ and Sox9, two key mediators that control adipocyte and chondrocyte differentiation. The acetylation status of PPARγ and Sox9 has opposite effects on its activity, thereby controlling cell fate decision.
Analytical modelling of bond stress at steel concrete interface due to corrosion
Authors: Hussein Luaay , Amleh Lamya
Published: March 2016

An analytical model is proposed for bond stresses at the corroded steel‐concrete interface in reinforced concrete. The concrete around the corroded bar is modelled as a thick‐walled cylinder – consisting of an inner cylinder of an anisotropic material and an outer cylinder made of an isotropic material – subjected to internal pressure exerted by the growth of corrosion products on the concrete wall at the interface. A frictional model is used to combine the action of confining pressure due to radial pressure produced by principal bar ribs and the pressure resulting from expansion of corrosion products. The analysis results using the proposed model show good agreement with the experimental results of several researchers.
Experiments to establish the loadbearing behaviour of lightweight sandwich beams using textile‐reinforced and expanded polystyrene concrete
Authors: Anh Nguyen Viet , Jesse Frank , Curbach Manfred
Published: March 2016

Textile‐reinforced concrete (TRC) is a combination of small‐grain high‐performance concrete (HPC) and high‐strength textile reinforcement. TRC enables thin layers and has high tensile and compressive strengths. In this paper, TRC was used for the face layers and combined with a core of lightweight expanded polystyrene concrete (EPC) to create lightweight sandwich beams without special joint reinforcement to connect the layers. The experimental testing of the loadbearing behaviour of this kind of sandwich beam, along with the influence of the shear span‐to‐depth ratio (a/d) as observed during three‐ and four‐point bending tests, will be summarized. The failure behaviour of the sandwich beams is influenced by the shear span‐to‐depth ratio, the type of bending test and the tensile capacity of the TRC layer. A diagonal tension failure occurred in experimental beams with 2.6 ≤ a/d ≤ 5.2 in three‐point bending tests and 3.1 ≤ a/d ≤ 4.1 in four‐point tests. The shear strength of the beams could be conservatively estimated according to the current European standards.
Changes in the expression of IL‐6‐Mediated MicroRNAs in the dorsal root ganglion under neuropathic pain in mice
Authors: Hori Naosuke , Narita Michiko , Yamashita Akira , Horiuchi Hiroshi , Hamada Yusuke , Kondo Takashige , Watanabe Moe , Igarashi Katsuhide , Kawata Miho , Shibasaki Masahiro , Yamazaki Mitsuaki , Kuzumaki Naoko , Inada Eiichi , Ochiya Takahiro , Iseki Masako , Mori Tomohisa , Narita Minoru
Published: March 2016

A multiplex analysis for profiling the expression of candidate microRNAs (miRNAs), which are small noncoding RNAs that function as key post‐transcriptional regulators, may lead to a better understanding of the complex machinery of neuropathic pain. In the present study, we performed a miRNA array analysis using tissues of the dorsal root ganglion (DRG), a primary site for pain processing, obtained from mice with partial sciatic nerve ligation. Among 1135 total miRNAs, 26 miRNAs showed up‐regulation (more than 2‐fold change) and only 4 miRNAs showed down‐regulation (less than 0.5‐fold change) in the DRG of nerve‐ligated mice. In a RT‐qPCR assay, the levels of miR‐21, miR‐431, and miR‐511‐3p were significantly increased on the ipsilateral side of the DRG from 3 to 7 days after sciatic nerve ligation. These elevations were almost absent in IL‐6 knockout mice. Furthermore, the expression level of miR‐21, but not those of miR‐431 or miR511‐3p, was significantly increased in exosomes extracted from blood of nerve‐ligated mice. These findings suggest that the increased expression of IL‐6‐regulated miR‐21, miR‐431, and miR‐511‐3p in the DRG and increased exosomal miR‐21 extracted from blood after sciatic nerve ligation may play at least a partial role in neuropathic pain. Synapse 70:317–324, 2016. © 2016 Wiley Periodicals, Inc.
Acteoside‐mediates chemoprevention of experimental liver carcinogenesis through STAT‐3 regulated oxidative stress and apoptosis
Authors: Peerzada Kaiser J. , Faridi Aamir H. , Sharma Love , Bhardwaj Subhash C. , Satti Naresh K. , Shashi Bhushan , Tasduq Sheikh A.
Published: March 2016

In the absence of an effective therapy against Hepatocellular Carcinoma (HCC), chemoprevention remains an important strategy to circumvent morbidity and mortality. Here, we examined chemopreventive potential of Acteoside (ACT), a plant derived phenylethanoid glycoside against an environmental and dietary carcinogen, diethylnitrosamine (DEN)‐induced rat hepatocarcinogenesis. ACT treatment (0.1 and 0.3% supplemented with diet) started 2 weeks before DEN challenge and continued for 18 weeks thereafter, showed a remarkable chemopreventive activity. ACT treatment resulted in reduced HCC nodules. Histopathology showed progressive tissue damage, necrosis (5 weeks), hepatocytic injury (10 weeks), anisonucleosis with presence of prominent nucleoli, sinusidal dilations, and lymphomono nuclear inflammation (18 weeks). Biochemical analysis showed hepatocytic injury (raised ALT, p < 0.001), inflammation [IL‐6, IFN‐γ (p < 0.05), and TNF‐α (p < 0.001)], apoptosis [elevated Caspase‐3 (p < 0.001)]. ACT at 0.1 and 0.3% ameliorated DEN‐induced pre‐hepatocarcinogenic manifestations. Mechanistic studies of ACT chemoprevention was elucidated using Hep3B cells with an aim to develop an in vitro DEN‐induced toxicity model. Hep3B was found to be a reliable and more sensitive towards DEN toxicity compared to HepG2 and HuH7 cells. ACT prevented DEN‐induced cytotoxicity (p < 0.001), DNA damage, and genotoxicity (micronuclei test, DNA ladder test, Hoechst staining, cell cycle analysis). ACT significantly (p < 0.001) scavenged DEN‐induced reactive oxygen species (ROS) levels and prevented mitochondrial membrane potential (MMP) loss. Immunoblotting showed ACT treatment reversed DEN‐induced NF‐κB, Bax, Cytochrome C, Bcl‐2, and Stat‐3 levels. We conclude that chemoprotective effect of ACT is mediated by STAT‐3 dependent regulation of oxidative stress and apoptosis and ACT has potential to be developed as a chemopreventive agent. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 782–798, 2016.
Triptolide induced cell death through apoptosis and autophagy in murine leukemia WEHI‐3 cells in vitro and promoting immune responses in WEHI‐3 generated leukemia mice in vivo
Authors: Chan Shih‐Feng , Chen Ya‐Yin , Lin Jen‐Jyh , Liao Ching‐Lung , Ko Yang‐Ching , Tang Nou‐Ying , Kuo Chao‐Lin , Liu Kuo‐Ching , Chung Jing‐Gung
Published: March 2016

Triptolide, a traditional Chinese medicine, obtained from Tripterygium wilfordii Hook F, has anti‐inflammatory, antiproliferative, and proapoptotic properties. We investigated the potential efficacy of triptolide on murine leukemia by measuring the triptolide‐induced cytotoxicity in murine leukemia WEHI‐3 cells in vitro. Results indicated that triptolide induced cell morphological changes and induced cytotoxic effects through G0/G1 phase arrest, induction of apoptosis. Flow cytometric assays showed that triptolide increased the production of reactive oxygen species, Ca2+ release and mitochondrial membrane potential (ΔΨm), and activations of caspase‐8, ‐9, and ‐3. Triptolide increased protein levels of Fas, Fas‐L, Bax, cytochrome c, caspase‐9, Endo G, Apaf‐1, PARP, caspase‐3 but reduced levels of AIF, ATF6α, ATF6β, and GRP78 in WEHI‐3 cells. Triptolide stimulated autophagy based on an increase in acidic vacuoles, monodansylcadaverine staining for LC‐3 expression and increased protein levels of ATG 5, ATG 7, and ATG 12. The in vitro data suggest that the cytotoxic effects of triptolide may involve cross‐talk between cross‐interaction of apoptosis and autophagy. Normal BALB/c mice were i.p. injected with WEHI‐3 cells to generate leukemia and were oral treatment with triptolide at 0, 0.02, and 0.2 mg/kg for 3 weeks then animals were weighted and blood, liver, spleen samples were collected. Results indicated that triptolide did not significantly affect the weights of animal body, spleen and liver of leukemia mice, however, triptolide significant increased the cell populations of T cells (CD3), B cells (CD19), monocytes (CD11b), and macrophage (Mac‐3). Furthermore, triptolide increased the phagocytosis of macrophage from peripheral blood mononuclear cells (PBMC) but not effects from peritoneum. Triptolide promoted T and B cell proliferation at 0.02 and 0.2 mg/kg treatment when cells were pretreated with Con A and LPS stimulation, respectively; however, triptolide did not significant affect NK cell activities in vivo. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 550–568, 2017.
Changes in ductus venosus flow profile in twin–twin transfusion syndrome: role in risk stratification
Authors: Wohlmuth C. , Osei F. A. , Moise K. J. , Wieser I. , Johnson A. , Papanna R. , Bebbington M. , Gardiner H. M.
Published: March 2016

Objectives

To evaluate changes in ductus venosus (DV) waveforms and the timing of these changes in twin–twin transfusion syndrome (TTTS), to relate these to disease severity and to assess the clinical applicability of the suggested measurements in the prediction of TTTS.

Methods

DV time intervals and velocity‐time integrals (VTI) normalized to cardiac cycle and total VTI, respectively, as well as velocity ratios were analyzed in 149 monochorionic diamniotic (MCDA) twin pairs. Pregnancies were assigned to the following groups: uncomplicated MCDA (n = 29); TTTS Stages I+II (n = 50); TTTS Stages III+IV (n = 49); and pre‐TTTS (n = 21), of which 14 remained stable and seven progressed to TTTS. Intertwin differences were calculated as larger/recipient minus smaller/donor and related to disease severity. Receiver–operating characteristics curve analysis was used to distinguish TTTS vs uncomplicated MCDA and pre‐TTTS progressing to TTTS vs non‐progressing pre‐TTTS. Intra‐ and interobserver reliability of measurement of DV parameters were evaluated using intraclass correlation coefficients (ICCs).

Results

No intertwin differences in DV parameters were found in uncomplicated MCDA pregnancies. Diastolic VTIs and filling times were significantly shorter in recipient twins in TTTS cases and in larger pre‐TTTS twins in comparison with their cotwins. Time intervals, VTIs and velocity ratios correlated significantly with Quintero stages. An intertwin difference in early filling time (eT) normalized to cardiac cycle, eT (%) ≤ −3.6%, could differentiate TTTS from uncomplicated MCDA pregnancies (82.8% sensitivity; 79.8% specificity) and eT (%) ≤ −2.8% predicted progression to TTTS (73.1% sensitivity; 67.4% specificity).

Conclusions

DV flow profiles and timing of waveform events are already altered in pre‐TTTS and early‐stage disease, reflecting abnormal ventricular filling and circulatory imbalance. Intertwin comparison of filling times and VTI may allow prediction of evolving TTTS in MCDA pregnancies. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.