bluuebunny/crossref_metadata_2025 huggingface dataset:
Single‐Crystalline p‐Type Zn3As2 Nanowires for Field‐Effect Transistors and Visible‐Light Photodetectors on Rigid and Flexible Substrates
Authors: Chen Gui , Liu Zhe , Liang Bo , Yu Gang , Xie Zhong , Huang Hongtao , Liu Bin , Wang Xianfu , Chen Di , Zhu Ming‐Qiang , Shen Guozhen
Published: December 2012

Zn3As2 is an important p‐type semiconductor with the merit of high effective mobility. The synthesis of single‐crystalline Zn3As2 nanowires (NWs) via a simple chemical vapor deposition method is reported. High‐performance single Zn3As2 NW field‐effect transistors (FETs) on rigid SiO2/Si substrates and visible‐light photodetectors on rigid and flexible substrates are fabricated and studied. As‐fabricated single‐NW FETs exhibit typical p‐type transistor characteristics with the features of high mobility (305.5 cm2 V−1 s−1) and a high Ion/Ioff ratio (105). Single‐NW photodetectors on SiO2/Si substrate show good sensitivity to visible light. Using the contact printing process, large‐scale ordered Zn3As2 NW arrays are successfully assembled on SiO2/Si substrate to prepare NW thin‐film transistors and photodetectors. The NW‐array photodetectors on rigid SiO2/Si substrate and flexible PET substrate exhibit enhanced optoelectronic performance compared with the single‐NW devices. The results reveal that the p‐type Zn3As2 NWs have important applications in future electronic and optoelectronic devices.
Photocrosslinkable Kappa‐Carrageenan Hydrogels for Tissue Engineering Applications
Authors: Mihaila Silvia M. , Gaharwar Akhilesh K. , Reis Rui L. , Marques Alexandra P. , Gomes Manuela E. , Khademhosseini Ali
Published: December 2012

Kappa carrageenan (κ‐CA) is a natural‐origin polymer that closely mimics the glycosaminoglycan structure, one of the most important constituents of native tissues extracellular matrix. Previously, it has been shown that κ‐CA can crosslink via ionic interactions rendering strong, but brittle hydrogels. In this study, we introduce photocrosslinkable methacrylate moieties on the κ‐CA backbone to create physically and chemically crosslinked hydrogels highlighting their use in the context of tissue engineering. By varying the degree of methacrylation, the effect on hydrogel crosslinking was investigated in terms of hydration degree, dissolution profiles, morphological, mechanical, and rheological properties. Furthermore, the viability of fibroblast cells cultured inside the photocrosslinked hydrogels was investigated. The combination of chemical and physical crosslinking procedures enables the formation of hydrogels with highly versatile physical and chemical properties, while maintaining the viability of encapsulated cells. To our best knowledge, this is the first study reporting the synthesis of photocrosslinkable κ‐CA with controllable compressive moduli, swelling ratios and pore size distributions. Moreover, by micromolding approaches, spatially controlled geometries and cell distribution patterns could be obtained, thus enabling the development of cell‐material platforms that can be applied and tailored to a broad range of tissue engineering strategies.
Application of femtosecond‐pulsed lasers for direct optical manipulation of biological functions
Authors: Yoon Jonghee , Park Junseong , Choi Myunghwan , Jong Choi Won , Choi Chulhee
Published: December 2012

Absorption of photon energy by cells or tissue can evoke photothermal, photomechanical, and photochemical effects, depending on the density of the deposited energy. Photochemical effects require a low energy density and can be used for reversible modulation of biological functions. Ultrashort‐pulsed lasers have a high intensity due to the short pulse duration, despite its low average energy. Through nonlinear absorption, these lasers can deliver very high peak energy into the submicrometer focus area without causing collateral damage. Absorbed energy delivered by ultrashort‐pulsed laser irradiation induces free electrons, which can be readily converted to reactive oxygen species (ROS) and related free radicals in the localized region. Free radicals are best known to induce irreversible biological effects via oxidative modification; however, they have also been proposed to modulate biological functions by releasing calcium ions from intracellular organelles. Calcium can evoke variable biological effects in both excitable and nonexcitable cell types. Controlled stimulation by ultrashort laser pulses generate intracellular calcium waves that can modulate many biological functions, such as cardiomyocyte beat rate, muscle contractility, and blood–brain barrier (BBB) permeability. This article presents optical methods that are useful therapeutic and research tools in the biomedical field and discuss the possible mechanisms responsible for biological modulation by ultrashort‐pulsed lasers, especially femtosecond‐pulsed lasers.
Non‐equilibrium polaritonics ‐ non‐linear effects and optical switching
Authors: Frank Regine
Published: December 2012

In this article a microscopic electronic non‐equilibrium effect, highly nonlinear polaritonics, is proposed to mediate an ultrafast all‐optical switching. The electronic band structure within gold (Au) nano grains shall be modified by external laser light, namely the Franz‐Keldysh effect, and the modified electronic density of states within the Au grains are coupled to a single mode photonic waveguide. Using this microscopic polaritonic coupling without ever including any macroscopic influences due to the geometric arrangement a strong transmission reduction originating from the established quantum interference is derived. The lifetime of the coupled states is heavily dependent on the Fano resonance type binding and the amplitude of the applied electric field. Besides the Fano signatures the microscopic coupling photon‐electron‐photon leads to a gaped electronic density of states within the Au nano‐grains.
A short walk through quantum optomechanics
Authors: Meystre Pierre
Published: December 2012

This paper gives a brief review of the basic physics of quantum optomechanics and provides an overview of some of its recent developments and current areas of focus. It first outlines the basic theory of cavity optomechanical cooling and gives a brief status report of the experimental state‐of‐the‐art. It then turns to the deep quantum regime of operation of optomechanical oscillators and covers selected aspects of quantum state preparation, control and characterization, including mechanical squeezing and pulsed optomechanics. This is followed by a discussion of the “bottom‐up” approach that exploits ultracold atomic samples instead of nanoscale systems. It concludes with an outlook that concentrates largely on the functionalization of quantum optomechanical systems and their promise in metrology applications.
Estimation and monitoring of traffic intensities with application to control of stochastic systems
Authors: Hung Ying‐Chao , Michailidis George , Chuang Shih‐Chung
Published: December 2012

The development of optimal control strategies for many stochastic models relies on the observed traffic intensity. However, implementation of such control strategies is often infeasible because of high operating costs induced by the fluctuations of traffic flows. In this study, we propose a framework for estimating and monitoring the traffic intensities of stochastic systems. The framework does not require knowledge of any input traffic statistics, and it allows us to adaptively estimate the intensity function over time and simultaneously detect its significant changes so that the control strategy can be adjusted accordingly without requiring high operating costs. Finally, a canonical queueing system with various types of input traffic is used to evaluate the effectiveness of the proposed framework. Copyright © 2012 John Wiley & Sons, Ltd.
Population transcriptomics with single‐cell resolution: A new field made possible by microfluidics
Authors: Plessy Charles , Desbois Linda , Fujii Teruo , Carninci Piero
Published: December 2012

Tissues contain complex populations of cells. Like countries, which are comprised of mixed populations of people, tissues are not homogeneous. Gene expression studies that analyze entire populations of cells from tissues as a mixture are blind to this diversity. Thus, critical information is lost when studying samples rich in specialized but diverse cells such as tumors, iPS colonies, or brain tissue. High throughput methods are needed to address, model and understand the constitutive and stochastic differences between individual cells. Here, we describe microfluidics technologies that utilize a combination of molecular biology and miniaturized labs on chips to study gene expression at the single cell level. We discuss how the characterization of the transcriptome of each cell in a sample will open a new field in gene expression analysis, population transcriptomics, that will change the academic and biomedical analysis of complex samples by defining them as quantified populations of single cells.
A simple and sensitive spectrofluorimetric method for the determination of furosemide using zinc(II)–1,4‐bis(imidazol‐1‐ylmethyl)benzene complexes
Authors: Liu Yali , Wang Huijuan , Wang Jian , Li Yuanfang
Published: December 2012

A novel spectrofluorometric method for the determination of furosemide (FUR) is described. The method is based on enhancement of fluorescence emission of FUR in the presence of zinc (II) complexes of 1,4‐bis(imidazol‐1‐ylmethyl)benzene. Under optimum conditions, the enhanced fluorescence intensity is linearly related to the concentration of FUR. The proposed method has been successfully applied to the determination of FUR in pharmaceutical preparations. The possible mechanism of this reaction is discussed briefly based on data from fluorescence spectroscopy, UV–vis absorption and infrared spectroscopy. Copyright © 2012 John Wiley & Sons, Ltd.
Extreme thermophilic ethanol production from rapeseed straw: Using the newly isolated Thermoanaerobacter pentosaceus and combining it with Saccharomyces cerevisiae in a two‐step process
Authors: Tomás Ana Faria , Karagöz Pınar , Karakashev Dimitar , Angelidaki Irini
Published: December 2012

The newly isolated extreme thermophile Thermoanaerobacter pentosaceus was used for ethanol production from alkaline‐peroxide pretreated rapeseed straw (PRS). Both the liquid and solid fractions of PRS were used. T. pentosaceus was able to metabolize the typical process inhibitors present in lignocellulosic hydrolysate, namely 5‐hydroxymethyl furfural (HMF) and furfural, up to concentrations of 1 and 0.5 g L−1, respectively. Above these levels, xylose consumption was inhibited up to 70% (at 3.4 g‐furfural L−1) and 75% (at 3.4 g‐HMF L−1). T. pentosaceus was able to grow and produce ethanol directly from the liquid fraction of PRS, without any dilution or need for additives. However, when the hydrolysate was used undiluted the ethanol yield was only 37% compared to yield of the control, in which pure sugars in synthetic medium were used. The decrease of ethanol yield was attributed to the high amounts of salts resulting from the alkaline‐peroxide pretreatment. Finally, a two‐stage ethanol production process from PRS using Saccharomyces cerevisiae (utilization of hexoses in the first step) and T. pentosaceus (utilization of pentoses in the second step) was developed. Results showed that the two strains together could achieve up to 85% of the theoretical ethanol yield based on the sugar composition of the rapeseed straw, which was 14% and 50% higher compared to the yield with the yeast or the bacteria alone, respectively. Biotechnol. Bioeng. 2013; 110: 1574–1582. © 2012 Wiley Periodicals, Inc.
A screening model to predict microalgae biomass growth in photobioreactors and raceway ponds
Authors: Huesemann M. H. , Van Wagenen J. , Miller T. , Chavis A. , Hobbs S. , Crowe B.
Published: December 2012

A microalgae biomass growth model was developed for screening novel strains for their potential to exhibit high biomass productivities under nutrient‐replete conditions in photobioreactors or outdoor ponds. Growth is modeled by first estimating the light attenuation by biomass according to Beer‐Lambert's Law, and then calculating the specific growth rate in discretized culture volume slices that receive declining light intensities due to attenuation. The model uses only two physical and two species‐specific biological input parameters, all of which are relatively easy to determine: incident light intensity, culture depth, as well as the biomass light absorption coefficient and the specific growth rate as a function of light intensity. Roux bottle culture experiments were performed with Nannochloropsis salina at constant temperature (23°C) at six different incident light intensities (10, 25, 50, 100, 250, and 850 µmol/m2 s) to determine both the specific growth rate under non‐shading conditions and the biomass light absorption coefficient as a function of light intensity. The model was successful in predicting the biomass growth rate in these Roux bottle batch cultures during the light‐limited linear phase at different incident light intensities. Model predictions were moderately sensitive to minor variations in the values of input parameters. The model was also successful in predicting the growth performance of Chlorella sp. cultured in LED‐lighted 800 L raceway ponds operated in batch mode at constant temperature (30°C) and constant light intensity (1,650 µmol/m2 s). Measurements of oxygen concentrations as a function of time demonstrated that following exposure to darkness, it takes at least 5 s for cells to initiate dark respiration. As a result, biomass loss due to dark respiration in the aphotic zone of a culture is unlikely to occur in highly mixed small‐scale photobioreactors where cells move rapidly in and out of the light. By contrast, as supported also by the growth model, biomass loss due to dark respiration occurs in the dark zones of the relatively less well‐mixed pond cultures. In addition to screening novel microalgae strains for high biomass productivities, the model can also be used for optimizing the pond design and operation. Additional research is needed to validate the biomass growth model for other microalgae species and for the more realistic case of fluctuating temperatures and light intensities observed in outdoor pond cultures. Biotechnol. Bioeng. 2013; 110: 1583–1594. © 2012 Wiley Periodicals, Inc.
Non‐invasive online detection of microbial lysine formation in stirred tank bioreactors by using calorespirometry
Authors: Regestein Lars , Maskow Thomas , Tack Andreas , Knabben Ingo , Wunderlich Martin , Lerchner Johannes , Büchs Jochen
Published: December 2012

Non‐invasive methods for online monitoring of biotechnological processes without compromising the integrity of the reactor system are very important to generate continuous data. Even though calorimetry has been used in conventional biochemical analysis for decades, it has not yet been specifically applied for online detection of product formation at technical scale. Thus, this article demonstrates a calorespirometric method for online detection of microbial lysine formation in stirred tank bioreactors. The respective heat generation of two bacterial strains, Corynebacterium glutamicum ATCC 13032 (wild‐type) and C. glutamicum DM1730 (lysine producer), was compared with the O2‐consumption in order to determine whether lysine was formed. As validation of the proposed calorespirometric method, the online results agreed well with the offline measured data. This study has proven that calorespirometry is a viable non‐invasive technique to detect product formation at any time point. Biotechnol. Bioeng. 2013; 110: 1386–1395. © 2012 Wiley Periodicals, Inc.
Global gene expression of Dehalococcoides within a robust dynamic TCE‐dechlorinating community under conditions of periodic substrate supply
Authors: West Kimberlee A. , Lee Patrick K.H. , Johnson David R. , Zinder Stephen H. , Alvarez‐Cohen Lisa
Published: December 2012

A microarray targeting four sequenced strains in the Dehalococcoides (Dhc) genus was used to analyze gene expression in a robust long‐term trichloroethene (TCE)‐degrading microbial community (designated ANAS) during feeding cycles that involve conditions of periodic substrate supply. The Dhc transcriptome was examined at three time‐points throughout a batch feeding cycle: T1 (27 h) when TCE, dichloroethene (DCE), and vinyl chloride (VC) were present; T2 (54 h) when only VC remained; and T3 (13 days) when Dhc had been starved of substrate for 9 days. Ninety percent of the Dhc open reading frames (ORFs) that were detected in the ANAS DNA were found to be expressed as RNA sometime during the time course, demonstrating extraordinary utilization of the streamlined genome. Ninety‐seven percent of these transcripts were differentially expressed during the time course indicating efficiency of transcription through regulation in Dhc. Most Dhc genes were significantly down‐regulated at T3, responding to a lack of substrate as would be expected. The tceA and vcrA genes, which code for proteins with known chlorinated ethene reduction functions, were highly expressed at both T1 and T2, whereas two other putative reductive dehalogenase genes (DET0173 and DET1545) were most highly expressed at T2, likely in response to the presence of VC. Hydrogenases were most highly expressed at T1, reflecting their important role in accumulating electrons used to initiate reductive dechlorination and other biosynthesis pathways. Cobalamin transport genes were preferentially expressed at T2, reflecting an increase in corrinoid transport as chloroethenes were degraded and a decrease in activity of the transport system after dehalogenation was complete. This is the first application of a microarray targeting a known genus, including both core genomes and identified strain‐specific genes, to improve our understanding of transcriptional dynamics within an undefined microbial community. Biotechnol. Bioeng. 2013; 110: 1333–1341. © 2012 Wiley Periodicals, Inc.
A redox trap to augment the intein toolbox
Authors: Callahan Brian P. , Stanger Matthew , Belfort Marlene
Published: December 2012

The unregulated activity of inteins during expression and consequent side reactions during work‐up limits their widespread use in biotechnology and chemical biology. Therefore, we exploited a mechanism‐based approach to regulate intein autocatalysis for biotechnological application. The system, inspired by our previous structural studies, is based on reversible trapping of the intein's catalytic cysteine residue through a disulfide bond. Using standard mutagenesis, the disulfide trap can be implemented to impart redox control over different inteins and for a variety of applications both in vitro and in Escherichia coli. Thereby, we first enhanced the output for bioconjugation in intein‐mediated protein ligation, also referred to as expressed protein ligation, where precursor recovery and product yield were augmented fourfold to sixfold. Second, in bioseparation experiments, the redox trap boosted precursor recovery and product yield twofold. Finally, the disulfide‐trap intein technology stimulated development of a novel bacterial redox sensor. This sensor reliably identified hyperoxic E. coli harboring mutations that disrupt the reductive pathways for thioredoxin and glutathione, against a background of wild‐type cells. Biotechnol. Bioeng. 2013; 110: 1565–1573. © 2012 Wiley Periodicals, Inc.
A thin‐walled polydimethylsiloxane bioreactor for high‐density hepatocyte sandwich culture
Authors: Tan Guo‐Dong Sean , Toh Guoyang William , Birgersson Erik , Robens Jeffrey , van Noort Danny , Leo Hwa Liang
Published: December 2012

In vitro drug testing requires long‐term maintenance of hepatocyte liver specific functions. Hepatocytes cultured at a higher seeding density in a sandwich configuration exhibit an increased level of liver specific functions when compared to low density cultures due to the better cell to cell contacts that promote long term maintenance of polarity and liver specific functions. However, culturing hepatocytes at high seeding densities in a standard 24‐well plate poses problems in terms of the mass transport of nutrients and oxygen to the cells. In view of this drawback, we have developed a polydimethylsiloxane (PDMS) bioreactor that was able to maintain the long‐term liver specific functions of a hepatocyte sandwich culture at a high seeding density. The bioreactor was fabricated with PDMS, an oxygen permeable material, which allowed direct oxygenation and perfusion to take place simultaneously. The mass transport of oxygen and the level of shear stress acting on the cells were analyzed by computational fluid dynamics (CFD). The combination of both direct oxygenation and perfusion has a synergistic effect on the liver specific function of a high density hepatocyte sandwich culture over a period of 9 days. Biotechnol. Bioeng. 2013; 110: 1663–1673. © 2012 Wiley Periodicals, Inc.
Analysis of a high‐throughput cone‐and‐plate apparatus for the application of defined spatiotemporal flow to cultured cells
Authors: Spruell Christopher , Baker Aaron B.
Published: December 2012

The shear stresses derived from blood flow regulate many aspects of vascular and immunobiology. In vitro studies on the shear stress‐mediated mechanobiology of endothelial cells have been carried out using systems analogous to the cone‐and‐plate viscometer in which a rotating, low‐angle cone applies fluid shear stress to cells grown on an underlying, flat culture surface. We recently developed a device that could perform high‐throughput studies on shear‐mediated mechanobiology through the rotation of cone‐tipped shafts in a standard 96‐well culture plate. Here, we present a model of the three‐dimensional flow within the culture wells with a rotating, cone‐tipped shaft. Using this model we examined the effects of modifying the design parameters of the system to allow the device to create a variety of flow profiles. We first examined the case of steady‐state flow with the shaft rotating at constant angular velocity. By varying the angular velocity and distance of the cone from the underlying plate we were able to create flow profiles with controlled shear stress gradients in the radial direction within the plate. These findings indicate that both linear and non‐linear spatial distributions in shear stress can be created across the bottom of the culture plate. In the transition and “parallel shaft” regions of the system, the angular velocities needed to provide high levels of physiological shear stress (5 Pa) created intermediate Reynolds number Taylor‐Couette flow. In some cases, this led to the development of a flow regime in which stable helical vortices were created within the well. We also examined the system under oscillatory and pulsatile motion of the shaft and demonstrated minimal time lag between the rotation of the cone and the shear stress on the cell culture surface. Biotechnol. Bioeng. 2013; 110: 1782–1793. © 2013 Wiley Periodicals, Inc.
Pressure assisted stabilization of biocatalysts at elevated temperatures: Characterization by dynamic light scattering
Authors: Kirsch Christian , Dahms Jessica , Kostko Andrei F. , McHugh Mark A. , Smirnova Irina
Published: December 2012

The effect of pressure, at elevated temperatures, is reported on the activity and stability of a thermophilic endo‐β‐glucanase from the filamentous fungus Talaromyces emersonii. The production of reduced sugars after treatment at different temperatures and pressures is used as a measure of the activity and stability of the enzyme. The activity of the enzyme is maintained to higher temperatures with increasing pressure. For example, the relative activity of endo‐β‐glucanase decreases to 30% after 4 h at 75°C and 1 bar, whereas it is preserved at 100% after 6 h at 75°C and 230 bar. High‐pressure dynamic light scattering is used to characterize the hydrodynamic radius of the enzyme as a function of pressure, temperature, and time. At higher temperature the hydrodynamic radius increases with time, whereas increasing pressure suppresses this effect. Changes in the hydrodynamic radius are correlated with the activity measurements obtained at elevated pressures, since the changes in the hydrodynamic radius indicate structural changes of the enzyme, which cause the deactivation. Biotechnol. Bioeng. 2013; 110: 1674–1680. © 2012 Wiley Periodicals, Inc.
Integration of stochastic simulation with multivariate analysis: Short‐term facility fit prediction
Authors: Stonier Adam , Pain David , Westlake Ashley , Hutchinson Nicholas , Thornhill Nina F. , Farid Suzanne S.
Published: December 2012

This article describes a decision‐support tool to help pinpoint the potential root causes of sub‐optimal short‐term facility fit issues in biopharmaceutical facilities. This was achieved by creating a tool that integrated stochastic simulation with advanced multivariate statistical analysis. Process fluctuations in product titers in cell culture, step yields, and chromatography eluate volumes were mimicked using Monte Carlo simulation data derived using a stochastic discrete‐event simulation model. The resulting stochastic datasets, with the computed consequences on key metrics such as product mass loss and cost of goods, were examined using advanced multivariate statistical techniques. Principal component analysis combined with clustering algorithms was used to analyze the complex datasets from complete industrial batch processes for biopharmaceuticals. The challenge of visualizing the multidimensional nature of the dataset was addressed using hierarchical and k‐means clustering as well as stacked parallel co‐ordinate plots to help identify process fingerprints and characteristics of clusters leading to sub‐optimal facility fit issues. Industrially‐relevant case studies are presented that focus on technology transfer challenges for therapeutic antibodies moving from early phase to late phase clinical trials. The case study details how sub‐optimal facility fit can be alleviated by allocating alternative product pool tanks. The impact of this operational change is then assessed by reviewing an updated process fingerprint. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 368–377, 2013
Cyberbullying among Adolescent Bystanders: Role of the Communication Medium, Form of Violence, and Empathy
Authors: Barlińska Julia , Szuster Anna , Winiewski Mikołaj
Published: December 2012

The purpose of this study was to understand how adolescents respond as bystanders of cyberbullying and to seek factors that might influence their actions. The study explored the effects of type of contact (online vs. face to face), form of violence (private vs. public), and empathy activation (affective and cognitive) on negative bystander behaviour understood as active participation in victimisation. The influence of experience of cyberbullying as perpetrator and as victim and gender on negative bystander behaviour was also controlled. Three experimental studies were conducted. The results indicate that online contact increases the likelihood of negative bystander behaviour. Private violence was less likely to elicit negative bystander action than was public violence. Previous experience of cyberperpetration was proved to increase the probability of negative bystander behaviour. Neither gender nor cybervictimisation affected the engagement in negative bystander behaviour in any of the studies. The inhibitory effect of empathy activation (both affective and cognitive) on negative bystander behaviour was demonstrated. Both types of cognitive empathy induction, emotion and behaviour focused, diminish the likelihood of negative bystander behaviour. The conclusions of the research are that negative bystander behaviour occurs more often in cyberspace than offline and that forms of intervention involving both affective and cognitive empathy may limit the negative bystander behaviour that supports cyberbullying. Copyright © 2012 John Wiley & Sons, Ltd.
Self‐transcendence and Self‐oriented Perspective as Mediators between Video game Playing and Aggressive Behaviour in Teenagers
Authors: Espinosa Pablo , Clemente Miguel
Published: December 2012

The present study examines the mediating effect of self‐transcendence and a self‐oriented perspective on the relationship between general video game playing and aggressive antisocial behaviour in a sample of 659 Spanish teenagers of both sexes aged 12 to 18 years (mean age = 15.31 years). Results show that there is a direct effect of the amount of video game playing on aggression, even when violent content is controlled for. Self‐transcendence and a self‐oriented perspective mediate this effect on aggression. These findings are in agreement with the hypothesis that the effects of media on behaviour are related to the socialisation pattern and role‐taking opportunities they offer, and not only due to the mere exposure to violent media. Consistent with the time displacement hypothesis, an interpretation of our results may be that the relationship between video game playing and antisocial behaviour comes from a deficit of social interaction and role‐taking opportunities. Not being able to adopt the perspective of others may result in a limited ability to predict the consequences of behaviour and understand the needs, desires, and intentions of others. This social perspective deficit may increase the chances of behaving antisocially through different processes. For instance, an individual may use aggressive behavioural patterns in the absence of a more elaborate behavioural repertoire, or the failure in predicting the effects of an aggressive behaviour may reduce the perception of its consequences. Copyright © 2012 John Wiley & Sons, Ltd.
Cyberbullying Research: New Perspectives and Alternative Methodologies. Introduction to the Special Issue
Authors: Dehue Francine
Published: December 2012

In this introduction, the definition of cyberbullying will be discussed, instruments to measure cyberbullying will be described, and the state of the art of research on cyberbullying will presented. To date, most studies of cyberbullying investigate demographic factors such as the prevalence of bullying and being victimized, gender, age, and negative outcomes. Some studies investigate responses to cyberbullying, but most of them are limited to technological solutions and informing adults. Hardly any attention is paid to the underlying social psychological mechanisms in relation to antisocial behaviour in online communities and to the role of peer groups. Moreover, most studies are cross‐sectional self‐reports. The present special issue aims to fill these gaps by presenting studies which are focused on alternative topics using alternative methodologies. Copyright © 2012 John Wiley & Sons, Ltd.
Coping with Cyberbullying: Differences Between Victims, Bully‐victims and Children not Involved in Bullying
Authors: Völlink Trijntje , Bolman Catherine A.W. , Dehue Francine , Jacobs Niels C.L.
Published: December 2012

This study investigated the relationship between the use of coping strategies to deal with daily stressors in general (n = 325) and the use of coping strategies to deal with cyberbullying in particular (n = 88) among children aged 11 and 12 years. Additionally, it investigated the impact of coping strategies on depression and health in victims of cyberbullying (n = 88). The results showed that victims differed significantly from bully‐victims (i.e. victims that also bully) and from children not involved in cyberbullying, in that they use certain emotion‐focused coping strategies for daily stressors in general more than others. Additionally, this study investigated among victims of cyberbullying the relation between coping strategies in daily life, cyberspecific coping, depressive feelings and health complaints. Coping through emotional expression, avoidance and depressive coping in daily life will lead to more cyberspecific depressive coping when confronted with cyberbullying. This in turn will lead to more depressive feelings and/or health complaints for victims of cyberbullying. These results stress the importance of teaching children how to stand up for themselves and employ effective coping strategies to deal with stress in daily life in general and to deal with cyberbullying in particular. Copyright © 2012 John Wiley & Sons, Ltd.
Structure of the O‐Glycosylated Conopeptide CcTx from Conus consors Venom
Authors: Hocking Henry G. , Gerwig Gerrit J. , Dutertre Sébastien , Violette Aude , Favreau Philipe , Stöcklin Reto , Kamerling Johannis P. , Boelens Rolf
Published: December 2012

The glycopeptide CcTx, isolated from the venom of the piscivorous cone snail Conus consors, belongs to the κA‐family of conopeptides. These toxins elicit excitotoxic responses in the prey by acting on voltage‐gated sodium channels. The structure of CcTx, a first in the κA‐family, has been determined by high‐resolution NMR spectroscopy together with the analysis of its O‐glycan at Ser7. A new type of glycopeptide O‐glycan core structure, here registered as core type 9, containing two terminal L‐galactose units {α‐L‐Galp‐(1→4)‐α‐D‐GlcpNAc‐(1→6)‐[α‐L‐Galp‐(1→2)‐β‐D‐Galp‐(1→3)‐]α‐D‐GalpNAc‐(1→O)}, is highlighted. A sequence comparison to other putative members of the κA‐family suggests that O‐linked glycosylation might be more common than previously thought. This observation alone underlines the requirement for more careful and in‐depth investigations into this type of post‐translational modification in conotoxins.
Mixed Linker Strategies for Organic Framework Functionalization
Authors: Bunck David N. , Dichtel William R.
Published: December 2012

Framework materials have attracted intense interest for gas storage, separations, catalysis, and other applications as a consequence of their periodicity, high specific surface area, and rational synthesis. Cocrystallizing multiple monomers with identical linking chemistry represents an emerging route to access materials with increased complexity and advanced functions. This Concept Article highlights three strategies for framework synthesis that employ mixtures of monomers with 1) identical linking geometries, 2) different linking geometries, or 3) in which one monomer is truncated with respect to the other. These approaches offer a diverse toolbox to modify framework topology, incorporate active functionality, and rationally control crystallite size and morphology.
A Pd(II)‐Catalyzed Oxidative Cyclization for the Preparation of Aryl‐Fused Six‐Membered Nitrogen Heterocycles with 2‐Acetoxy Functionality
Authors: Wang Xiaolei , Wu Zhengxing , Zhu Xiaowen , Ye Chenghao , Jiang Feng , Zhang Wanbin
Published: December 2012

A Pd(II)‐catalyzed oxidative cyclization of olefinic tosylamides was developed for the preparation of aryl‐fused and N‐containing six‐membered heterocycles. Under optimized conditions the reaction proceeded with high activity and selectivity, with yields of up to 83% being obtained. This procedure provides a facile and efficient route to the aforementioned heterocycles with 2‐acetoxy functionality.
Expedient Synthesis of (R)‐Curcuphenol: A Chiral Pool Strategy
Authors: Feng Jing , Zhu Guili , Liu Bo , Zhou Xiangdong
Published: December 2012

Curcuphenol is an interesting sesquiterpenoid with diverse bioactivities. Exploration of a concise and scalable synthetic route is still of significance in spite that many asymmetric total syntheses have been achieved. We report an expedient asymmetric synthesis of (R)‐curcuphenol from citronellal, which features only two purification operations in the overall six‐step synthesis.
A Study of Nano Materials and Their Reactions in Liquid Using in situ Wet Cell TEM Technology
Authors: Chen Xin , Zhou Lihui , Wang Ping , Zhao Chongjun , Miao Xiaoli
Published: December 2012

Several nano material and reaction systems were in situ monitored with an electrochemical TEM wet cell set up. In a 1 g/L sliver particle aqueous solution, the particles were observed to be ca. 10 nm sized, in both discrete particle and nano cluster forms. The silver particles were attached to the 50 nm‐thick Si3N4 windows of the wet cell and could not move freely in the liquid. With a SiCl4 liquid loaded in the wet cell, silicon nano materials were controllably grown on the wet cell windows by means of a liquid phase electron beam induced deposition (EBID) method. The deposited nano dots were nicely round‐shaped, and demonstrated a power law growth dependency on beam exposure time in a log‐log plot. In a NiCl2 solution/Ni system, both electrochemical deposition and dissolution of the nickel nano films were observed while applying electric biases on to the nickel electrodes in the wet cell. Instead of extensional growth on existing crystals, interestingly, it is more commonly observed that new nickel nano particles grow out in front of the existing film first and then merged into the film. The wet cell set up is demonstrated to be a versatile tool for nano liquid system research.
Uptake and Accumulation of Arsenic in Different Organs of Carrot Irrigated with As‐Rich Water
Authors: Mayorga Paloma , Moyano Amelia , Anawar Hossain M. , Garcia‐Sanchez Antonio
Published: December 2012

Irrigation with arsenic (As)‐rich water in agricultural soil may increase high levels of As in crops and cause food chain contamination. In this study, a greenhouse experiment was established using Spanish agricultural soil (Valladolid and Segovia provinces), that are extensively cultivated for carrot plant, to investigate the process of As uptake, bioaccumulation, and translocation of As from root to shoot and leaves in carrot plant. Arsenic concentrations in different organs of carrot plant, rhizosphere soil, and soil solutions were determined by hydride generation atomic absorption spectrometry (AAS). High concentrations of As in irrigation water, and the alkaline and sandy character of this soil enhanced As uptake in carrot plants indicating the potential health risk from consumption of carrots cultivated in these areas. Bioaccumulation of As into the leaves and roots increased with increase of As concentration in irrigation water. Both roots and leaves demonstrated a higher accumulation rate of As at an As concentration of 41 than 131 µg L−1 in the soil solution. The ratios of Asroot/Asleaves showed no statistically significant differences for the different irrigation treatments, and had an average value of 0.36 indicating the high magnitude of As translocation from roots to leaves in carrot plants. The leaves of carrots had a higher affinity for As than roots did. The correlation between As uptake by leaves or roots of carrots and the soluble As in rhizosphere soil did not demonstrate a linear or a plateau curve, indicating a slow but continuous constant As absorption which could be prolonged over time with high potential environmental risks.
Closed Hypersurfaces Driven by Mean Curvature and Inner Pressure
Authors: Notz Thilo
Published: December 2012

We introduce a hyperbolic equation that describes the motion of closed hypersurfaces in a Riemannian manifold with surface tension and inner pressure as driving forces. In the case of spherical surfaces this equation can be considered as an idealized mathematical model for a moving soap bubble. The equation is derived as an Euler‐Lagrange equation from a suitable action integral. It is a quasi‐linear degenerate hyperbolic PDE of second order that describes the motion of the surfaces extrinsically.

Our main results are the solution of the Cauchy problem by means of the Nash‐Moser inverse function theorem, a continuation criterion, and stability estimates. © 2012 Wiley Periodicals, Inc.
Right frontal lobe glioma presenting as anorexia nervosa: Further evidence implicating dorsal anterior cingulate as an area of dysfunction
Authors: Goddard Elizabeth , Ashkan Keyoumars , Farrimond Stuart , Bunnage Martin , Treasure Janet
Published: December 2012

Objective:

The association of anorexia nervosa (AN) with organic brain lesions may offer insight into underlying illness neuropathology. A systematic review reported an association between AN and lesions located in the right frontal lobe. To date, no studies have studied such a case longitudinally. A case of a male presenting with AN and a frontal lobe glioma is described.

Method:

The clinical symptoms and subsequent medical and neuropsychological investigations before and after surgery are reviewed.

Results:

The remission of ED symptoms is observed at 2 year post‐surgery follow up.

Discussion:

The features of this case are set into the context of recent conceptualizations of AN and the clinical implications for identifying individuals with underlying organic causes. © 2012 by Wiley Periodicals, Inc. (Int J Eat Disord 2013)
Monitoring considerations for a dynamic dune restoration project: Pacific Rim National Park Reserve, British Columbia, Canada.
Authors: Darke Ian B. , Eamer Jordan B. R. , Beaugrand Hawley E. R. , Walker Ian J.
Published: December 2012

Historically, management of coastal dune systems has often involved artificial stabilization of active sand surfaces in order for coastal areas to be more easily controlled and modified for human benefit. In North America, the introduction of invasive grasses, namely European and American beach (marram) grasses (Ammophila spp.) has been one of the most successful strategies used for stabilizing active coastal dune sands. Recent research has demonstrated, however, that stabilization of coastal dunes often leads to reduced landform complexity and resilience, as well as declines in species diversity. More ‘dynamic’ restoration efforts have emerged over the past 20 years that encourage dune mobility and aeolian activity in order to provide a more resilient biogeomorphic system. In North America, there is generally little research relating restoration methods and outcomes to geomorphic responses despite the fundamental importance of sedimentary processes and dune morphodynamics in broader ecosystem function. This paper aims to better situate dynamic dune restoration within current geomorphic understanding. A brief review of key terms and concepts used in the emerging field of dynamic dune restoration is provided and expanded upon with respect to geomorphologic considerations. A case study of a recent dynamic restoration effort in Pacific Rim National Park Reserve, British Columbia, Canada is provide to demonstrate how these concepts are applied. Introduction of European marram at this site, coupled with a warming climate and increased precipitation in recent decades at this site, is thought to be associated with a rapid decline in aeolian activity, system stabilization and accelerated ecological succession. Preliminary results on the response of the dune system to mechanical removal of Ammophila are presented to provide the foundation for a research framework to guide the broader restoration project. Recommendations for improving treatment methodologies and monitoring protocols are provided to aid future restoration projects of this nature. Copyright © 2013 John Wiley & Sons, Ltd.
Shelf life of air and modified atmosphere‐packaged fresh tilapia (Oreochromis niloticus) fillets stored under chilled and superchilled conditions
Authors: Cyprian Odoli , Lauzon Hélène L. , Jóhannsson Ragnar , Sveinsdóttir Kolbrún , Arason Sigurjón , Martinsdóttir Emilía
Published: December 2012

Optimal packaging and storage conditions for fresh tilapia fillets were established by evaluating sensory and microbiological changes, as well as monitoring physicochemical properties. Nile tilapia (Oreochromis niloticus) farmed in recirculation aquaculture system was filleted, deskinned, and packaged in air and 50% CO2/50% N2 prior to chilling and superchilling storage at 1°C and −1°C. Sensory analysis of cooked samples revealed a shelf life of 13–15 days for air‐packaged fillets during storage at 1°C and 20 days at −1°C. At the end of shelf life in air‐packaged fillets, total viable counts (TVC) and pseudomonads counts reached log 8 colony‐forming units (CFU) g−1. In 50% CO2/50% N2‐packaged fillets, the lag phase and generation time of bacteria were extended and recorded counts were below the limit for consumption (<log 8 CFU g−1) after 23 days of storage at both 1°C and −1°C. However, modified atmosphere (MA) packaging negatively affected color characteristics of the fillets soon after packaging (day 6). Color is an important indicator of tilapia fillets quality and a major factor in influencing retail purchase decisions. In view of that, air packaged at −1°C storage temperature was the optimal condition for fresh tilapia fillets. Total volatile basic nitrogen (TVB‐N) and trimethylamine (TMA) were not good indicators of spoilage of tilapia fillets in this study.
Flaking process increases the NF‐κB inhibition activity and melanoidin extractability of coffee
Authors: Chu Yi‐Fang , Hu Kang , Hatzold Thomas , Black Richard M. , Chen Don
Published: December 2012

Research on the health impacts of coffee has escalated. However, few studies were devoted to understanding the potential impact of mechanical processing on coffee's chemistry and subsequent health implications. Coffee flaking is a commonly used process to improve extractability and aroma characteristics. In this study, we studied the biochemical activity, chemical composition, and microstructure of coffee before and after flaking. We found that flaked coffee extract had 3.3‐fold higher activity in inhibiting nuclear factor‐kappa B (NF‐κB) activation than regular coffee extract. Interestingly, flaking did not significantly alter the amount of coffee phenolics. It increased coffee melanoidin, by 2.1‐fold, which likely contributed to the observed higher activity in inhibiting NF‐κB activation. Flaking crushed cell walls revealed by microscopy might possibly result in disruption of polysaccharide entanglement and release of high‐molecular‐weight compounds, such as melanoidins. Consequently, the increased melanoidin content in the brew resulted in the increased inhibition of NF‐κB activation. Small molecules, like coffee phenolics, are readily soluble in water during coffee brewing even without flaking, suggesting that flaking has no effect on its extractability. In summary, our investigation revealed that flaking enhanced NF‐κB inhibition activity, possibly through the release of melanoidins from crushed cell microstructures.
The effect of music therapy compared with general recreational activities in reducing agitation in people with dementia: a randomised controlled trial
Authors: Vink A. C. , Zuidersma M. , Boersma F. , de Jonge P. , Zuidema S. U. , Slaets J. P. J.
Published: December 2012

Objective

This study aimed to compare the effects of music therapy with general recreational day activities in reducing agitation in people with dementia, residing in nursing home facilities.

Methods

In a randomised controlled design, residents with dementia (n = 94) were allocated to either music therapy or recreational activities. Both music therapy and general activities were offered twice weekly for 4 months. Changes in agitation were measured with a modified Cohen‐Mansfield Agitation Inventory (CMAI) at four intervals on each intervention day. A mixed model analysis was used to evaluate the effectiveness of music therapy, compared with general activities, on CMAI scores at 4 h after the intervention, controlled for CMAI scores at 1 h before the session and session number.

Results

Data were analysed for 77 residents (43 randomised to music therapy and 34 to general activities). In both groups, the intervention resulted in a decrease in agitated behaviours from 1 h before to 4 h after each session. This decrease was somewhat greater in the music therapy group than in the general activities group, but this difference was statistically not significant (F = 2.885, p = 0.090) and disappeared completely after adjustment for Global Deterioration Scale stage (F = 1.500; p = 0.222).

Conclusions

Both music therapy and recreational activities lead to a short‐term decrease in agitation, but there was no additional beneficial effect of music therapy over general activities. More research is required to provide insight in the effects of music therapy in reducing agitation in demented older people. Copyright © 2012 John Wiley & Sons, Ltd.