bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Spherical Catalyst Particles on Gas‐Liquid Flow Regimes in Minichannels with Square Cross Section
Authors: Haase Stefan , Langsch Robert , Bauer Tobias , Lange Rüdiger
Published: February 2014

The design of process equipment involving minichannel structures necessitates detailed knowledge on the flow conditions inside the apparatus. Here, flow regimes in empty and sphere‐packed square channels were investigated by using optical flow visualization with a high‐speed camera. Flow maps as well as new correlations to predict the flow regime transitions based on the dimensionless gas and liquid Weber numbers are presented. Segmented flow regimes occurred in the studied empty and packed channels for very low gas and low liquid Weber numbers. Such a liquid flow in separate compartments may contribute to the design of highly efficient contacting apparatuses.
Microbial Fuel Cells as Discontinuous Portable Power Sources: Syntropic Interactions with Anode‐Respiring Bacteria
Authors: Gao Yaohuan , An Junyeong , Ryu Hodon , Lee Hyung‐Sool
Published: February 2014

For microbial fuel cells (MFCs) to work as portable power sources used in a discontinuous manner, anode‐respiring bacteria (ARB) should survive for at least several days in the absence of exogenous electron donors, and immediately generate current upon addition of an electron donor. Here, we proved that biopolymer‐accumulating bacteria provide substrate (fuel) for ARB to generate current in lack of exogenous electron donor in 4 days, which allows MFCs to be used as portable power sources.
Nickel–Tungsten Carbide Catalysts for the Production of 2,5‐Dimethylfuran from Biomass‐Derived Molecules
Authors: Huang Yao‐Bing , Chen Meng‐Yuan , Yan Long , Guo Qing‐Xiang , Fu Yao
Published: February 2014

The development of new catalytic systems for the conversion of biomass‐derived molecules into liquid fuels has attracted much attention. We propose a non‐noble bimetallic catalyst based on nickel–tungsten carbide for the conversion of the platform molecules 5‐(hydroxymethyl)furfural into the liquid‐fuel molecule 2,5‐dimethylfuran (DMF). Different catalysts, metal ratios and reaction conditions have been tested and give rise to a 96% yield of DMF. The catalysts have been characterized and are discussed. The reaction mechanism is also explored through capture of reaction intermediates. The analysis of the reaction mixture over different catalysts is presented and helps to understand the role of nickel and tungsten carbide during the reaction.
Unprecedented Formation of the First Alkaline‐Earth‐Metal Complex Bearing an Asymmetrical gem‐Dithiolato Heteroscorpionato Ligand
Authors: Sánchez‐Barba Luis F. , Garcés Andrés , Fernández‐Baeza Juan , Otero Antonio , Honrado Manuel , Lara‐Sánchez Agustín , Rodríguez Ana M. , López‐Solera Isabel
Published: February 2014

The reaction of the lithium dithioacetate derivative [Li(bdmpzdta)(THF)] [bdmpzdta = bis(3,5‐dimethylpyrazol‐1‐yl)dithioacetate] with 1 equiv. of C3H5MgCl proceeds in high yield to give the first alkaline‐earth‐metal complex bearing an asymmetrical gem‐dithiolato moiety, namely, [Mg(κ3‐NNS‐μ‐S‐bppbte)]3 (1) [bppbte = 1,1‐bis(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)pent‐4‐ene‐2,2‐bis(thiolate)]. This is achieved through an unprecedented insertion reaction of the allyl group into the C=S bond. In contrast, the reaction with the Grignard reagents MeMgCl or EtMgCl leads to the formation of the six‐coordinate sandwich species [Mg(κ3‐bdmpzdta)2] (2), as a result of a rapid ligand redistribution. The molecular structures of 1 and 2 in the solid state have been unambiguously established by single‐crystal X‐ray diffraction studies, which reveal a trinuclear entity with a twisted six‐membered core for 1, in which all magnesium centers are arranged in a distorted trigonal bipyramidal geometry, whereas in 2 the magnesium center has an octahedral coordination environment with two heteroscorpionato ligands, which bind in a κ3‐NNS fashion with a relative trans disposition.
A Sustainable Preparation of Glycerol Carbonate from Glycerol and Urea Catalyzed by Hydrotalcite‐Like Solid Catalysts
Authors: Sun Yongfa , Tong Xinli , Wu Zhidong , Liu Jinbiao , Yan Yongtao , Xue Song
Published: February 2014

The selective synthesis of glycerol carbonate from glycerol and urea catalyzed by hydrotalcite‐like compounds has been performed under solvent‐free conditions. Different hydrotalcite‐like compounds have been prepared and characterized by X‐ray diffraction (XRD) and infrared spectroscopic techniques (FTIR), which confirm the well‐defined structure of these materials. The investigations of the reaction of glycerol and urea showed that hydrotalcite‐like compounds including Mg, Zn, and Al elements have very high catalytic activity. As a result, 89.8 % conversion and 93.2 % selectivity for glycerol carbonate were obtained under suitable conditions. Compared to the addition of Zn, the addition of Ga and Ni is disadvantageous to the catalytic activity of Mg–Al hydrotalcite. These phenomena are consistent with the activity of the halides of these metals. The difference between the XRD and FTIR results of fresh and used catalysts showed the existence of dissolved metal, which was related to the catalytic activity in the reaction. The kinetic study with hydrotalcite catalysts was also performed. The relationship between the amounts of active species in liquid phase and the yield of product and recycling tests indicated that homogeneous catalysis was dominant during the entire reaction.
Polymer Solar Cells Processed Using Anisole as a Relatively Nontoxic Solvent
Authors: Venkatesan Swaminathan , Chen Qiliang , Ngo Evan C. , Adhikari Nirmal , Nelson Kelly , Dubey Ashish , Sun Jianyuan , Bommisetty Venkateswara , Zhang Cheng , Galipeau David , Qiao Qiquan
Published: February 2014

In this study, a relatively nontoxic single solvent, anisole, was successfully used to process polymer solar cells. Blends cast with anisole showed higher polymer aggregation due to lower solubility. Polymer aggregation led to isolated regions that can trap charges in the polymer phase in anisole‐based cells, supported by photo‐charge extraction by the linearly increasing voltage (photo‐CELIV) technique. However, polymer aggregation resulted in lower bimolecular recombination due to a decreased amount of polymer–PCBM interface as seen in transient photocurrent/photovoltage measurements. The higher charge trapping was compensated by the lower bimolecular recombination and therefore cells fabricated with anisole solvent delivered comparable photovoltaic performance to reference to cells processed with chlorobenzene (CB). Overall anisole was proved to be a friendly solvent to process organic photovoltaics thereby decreasing the risk to human health for large scale production.
High‐resolution p‐adaptive DG simulations of flows with moving shocks
Authors: Panourgias Konstantinos T. , Papoutsakis Andreas , Ekaterinaris John A.
Published: February 2014

High‐order accurate DG discretization is employed for Reynolds‐averaged Navier–Stokes equations modeling of complex shock‐dominated, unsteady flow generated by gas issuing from a shock tube nozzle. The DG finite element discretization framework is used for both the flow field and turbulence transport. Turbulent flow in the near wall regions and the flow field is modeled by the Spalart–Allmaras one‐equation model. The effect of rotation on turbulence modeling for shock‐dominated supersonic flows is considered for accurate resolution of the large coherent and vortical structures that are of interest in high‐speed combustion and supersonic flows. Implicit time marching methodologies are used to enable large time steps by avoiding the severe time step limitations imposed by the higher order DG discretizations and the source terms. Sufficiently high mesh density is used to enable crisp capturing of discontinuities. A p − type refinement procedure is employed to accurately represent the vortical structures generated during the development of the flow. The computed solutions showed qualitative agreement with experiments. Copyright © 2014 John Wiley & Sons, Ltd.
Detecting changing river temperatures in England and Wales
Authors: Orr Harriet G. , Simpson Gavin L. , des Clers Sophie , Watts Glenn , Hughes Mike , Hannaford Jamie , Dunbar Michael J. , Laizé Cédric L. R. , Wilby Rob L. , Battarbee Richard W. , Evans Rob
Published: February 2014

Changes in water temperature can have important consequences for aquatic ecosystems, with some species being sensitive even to small shifts in temperature during some or all of their life cycle. While many studies report increasing regional and global air temperatures, evidence of changes in river water temperature has, thus far, been site specific and often from sites heavily influenced by human activities that themselves could lead to warming. Here we present a tiered assessment of changing river water temperature covering England and Wales with data from 2773 locations. We use novel statistical approaches to detect trends in irregularly sampled spot measurements taken between 1990 and 2006. During this 17‐year period, on average, mean water temperature increased by 0.03 °C per year (±0.002 °C), and positive changes in water temperature were observed at 2385 (86%) sites. Examination of catchments where there has been limited human influence on hydrological response shows that changes in river flow have had little influence on these water temperature trends. In the absence of other systematic influences on water temperature, it is inferred that anthropogenically driven climate change is driving some of this trend in water temperature. © 2014 The Authors. Hydrological Processes published by John Wiley & Sons Ltd.
Sensitivity of the multiannual thermal dynamics of a deep pre‐alpine lake to climatic change
Authors: Valerio Giulia , Pilotti Marco , Barontini Stefano , Leoni Barbara
Published: February 2014

The study of the multiannual thermal dynamics of Lake Iseo, a deep lake in the Italian pre‐alpine area, is presented. Interflow was found to be the dominant river entrance mode, suggesting future susceptibility of the lake thermal structure to the overall effects of climate change expected in the upstream alpine watershed. A lake model employed the results of a long‐term hydrologic model to simulate the effects of a climate change scenario on the lake's thermal evolution for the period 2012–2050. The model predicts an overall average increase in the lake water temperature of 0.012 °C/year and a reinforced Schmidt thermal stability of the water column in the winter up to 800 J/m2. Both these effects may further hinder the deep circulation process, which is vital for the oxygenation of deep water. Copyright © 2014 John Wiley & Sons, Ltd.
Snow water equivalent time‐series forecasting in Ontario, Canada, in link to large atmospheric circulations
Authors: Sarhadi Ali , Kelly Richard , Modarres Reza
Published: February 2014

The present study applies different time‐series models for forecasting daily and monthly snow water equivalent (SWE) data in Ontario, Canada, during 1987–2011. For daily time series, which showed a significant negative trend, four categories of the autoregressive moving‐average (ARMA) and ARMA model with exogenous variables (ARMAX) were applied. The North Atlantic Oscillation, Southern Oscillation Index and Pacific/North American Pattern, as large‐scale atmospheric anomalies, as well as temperature time series are considered as exogenous variables for ARMAX models. According to the multicriteria performance evaluation, a time‐trend ARMAX model demonstrated the best performance for modelling and forecasting daily SWE. Two models, seasonal autoregressive integrated moving average (SARIMA) and SARIMA with exogenous variables (SARIMAX), were also fitted to the monthly SWE time series. The results revealed that the SARIMAX model showed a better performance than the SARIMA model according to multicriteria evaluation. The three nonparametric tests, Wilcoxon, Levene and Kolmogorov–Smirnov for forecasting evaluation demonstrated that the selected time‐series models had enough reliability for short‐term SWE forecasting in Ontario. The results of this study also demonstrate the importance of incorporating both trend and appropriate exogenous variables for SWE time‐series modelling and forecasting. Copyright © 2014 John Wiley & Sons, Ltd.
High‐risk HPV types and head and neck cancer
Authors: Michaud Dominique S. , Langevin Scott M. , Eliot Melissa , Nelson Heather H. , Pawlita Michael , McClean Michael D. , Kelsey Karl T.
Published: February 2014

Although HPV16 has been strongly implicated in oropharyngeal carcinogenesis, the role of other high‐risk HPV types in the etiology of head and neck cancer remains unclear. To date, few data exist addressing the nature of the association between antibodies to oncogenic proteins of non‐HPV16 HPVs in relation to head and neck cancer. We examined the relationship between multiple HPV types (HPV6, 11, 16, 18, 31, 33, 45, 52, 58) and head and neck squamous cell carcinoma (HNSCC) in a large population‐based case–control study (1069 cases and 1107 controls). Serological measures for HPV types included antibodies to L1, E6 and/or E7. In a secondary analysis, we excluded HPV16 seropositive subjects to examine independent associations with other high‐risk HPVs. All analyses were adjusted for age, race, sex, education, smoking and alcohol consumption. Statistically significant associations were observed for HPV16, 18, 33 and 52 and risk of HNSCC after mutually adjusting for HPV types. Among HPV16 seronegative subjects, elevated risks of HNSCC were observed for HPV18 E6 (OR = 4.19, 95% CI = 1.26–14.0), HPV33 E6 (OR = 7.96, 95% CI = 1.56–40.5) and HPV52 E7 (OR = 3.40, 95% CI = 1.16–9.99). When examined by tumor type, associations with HPV18 and HPV33 remained statistically significant for oropharyngeal cancer, and HPV52 was associated with oral cancer. In addition, magnitude of associations for HNSCC increased markedly with increasing number of seropositive high‐risk HPV infections. High‐risk HPV types, other than HPV16, are likely to be involved in the etiology of HNSCC.
Deconvolution of Raman spectra for the quantification of ternary high‐pressure phase equilibria composed of carbon dioxide, water and organic solvent
Authors: Schuster Julian J. , Will Stefan , Leipertz Alfred , Braeuer Andreas
Published: February 2014

The paper reports on a routine to extract the composition of multi‐component mixtures from their Raman spectra at elevated pressures. The strategy is based on fitting weighted Raman spectra of the pure compounds to the measured Raman spectrum of the mixture, also considering the effects of intermolecular interactions onto the Raman spectra by applying Gaussian and Voigt profile deconvolution of the Raman peaks. Thereby, an improved accuracy compared to previous evaluation strategies could be obtained. The more accurate data of the ternary mixtures of carbon dioxide, water and organic solvents are presented. Copyright © 2014 John Wiley & Sons, Ltd.
The Benefits of Online Crowdfunding for Fund‐Seeking Business Ventures
Authors: Macht Stephanie A. , Weatherston Jamie
Published: February 2014

Crowdfunding through the Internet, a new fundraising technique for small business ventures, can benefit fund‐seeking companies by helping to overcome funding difficulties, providing value‐added involvement, facilitating access to further funding, providing publicity and contacts, and enabling fundraising with only limited or no loss of control and ownership.
Impact of Strategy–Capital Structure on Firms' Overall Financial Performance
Authors: Agnihotri Arpita
Published: February 2014

Firms may be able to lower their cost of capital and improve their financial performance by fitting their strategy to the mode of financing.
Asymmetric Procurement in the Public Sector
Authors: Deasy Michelle , White Gareth R.T. , Parfitt Scott , Ringwald Kath
Published: February 2014

Certain operational issues related to information technologies and staff training turn out to be particularly important for successful procurement practice in public emergency services.
An Analysis of the Earnings Quality of Iranian Public and Private Firms
Authors: Alipour Mohammad , Barandagh Mohammad Imani , Nazari Naser
Published: February 2014

A significant positive relationship is found in Iran between private ownership and earnings, as private ownership increases the transparency of financial information.
LIBOR, EURIBOR, and the Regulation of Capital Markets: A Review of the Efficient Markets Hypothesis
Authors: Ojo Marianne
Published: February 2014

The recent rate‐rigging scandals serve as a reminder that capital markets need to be properly regulated.
The Kinetic Model of n‐Decane Oxidation in the Presence of Inhibitory Composition
Authors: Tikhonova M. V. , Garifullina G. G. , Gerchikov A. Ya. , Spivak S. I.
Published: February 2014

This article addresses mathematical modeling of the reaction of inhibited organic compounds oxidation. It was proposed to solve the inverse problems of chemical kinetics by using the index method of constrained global minimization of the deviation between the calculated and experimental data. This approach allows us to use more complete information about the chemical process which, in its turn, reduces the range of possible solutions, narrows down the domain of uncertainty, and improves the quality of mathematical model of chemical reactions. The index method was applied to solving inverse kinetic problem for the reaction of n‐decane oxidation in the presence of a p‐oxydiphenylamine/n‐decyl alcohol inhibitory composition.
Photoinduced Copper(I)‐Catalyzed Click Chemistry by the Electron Transfer Process Using Polynuclear Aromatic Compounds
Authors: Yilmaz Gorkem , Iskin Birol , Yagci Yusuf
Published: February 2014

Based on electron‐transfer reactions of the excited states of polynuclear aromatic compounds, such as anthracene, pyrene, and phenothiazine and Cu(II), a long‐wavelength photoinduced copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) click reaction is developed. Although at different rates, all the sensitizers are shown to efficiently reduce Cu(II) to Cu(I), which catalyzes the click reaction between small organic compounds. The applicability of the method for the construction of various macromolecular architectures, including telechelic polymers and block copolymers is demonstrated. Spectroscopic and chromatographic investigations reveal that successful macromolecular syntheses are achieved.

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Morphologic changes of dendritic spines of striatal neurons in the levodopa‐induced dyskinesia model
Authors: Nishijima Haruo , Suzuki Satoko , Kon Tomoya , Funamizu Yukihisa , Ueno Tatsuya , Haga Rie , Suzuki Chihiro , Arai Akira , Kimura Tamaki , Suzuki Chieko , Meguro Reiko , Miki Yasuo , Yamada Junko , Migita Keisuke , Ichinohe Noritaka , Ueno Shinya , Baba Masayuki , Tomiyama Masahiko
Published: February 2014

Maladaptive plasticity at corticostriatal synapses plays an important role in the development of levodopa‐induced dyskinesia. Recently, it has been shown that synaptic plasticity is closely linked to morphologic changes of dendritic spines. To evaluate morphologic changes of dendritic spines of two types of striatal medium spiny neurons, which project to the internal segment of globus pallidus or the external segment of globus pallidus, in the levodopa‐induced dyskinesia model, we used 6‐hydroxydopamine‐lesioned rats chronically treated with levodopa. Dendritic spines were decreased and became enlarged in the direct pathway neurons of the model of levodopa‐induced dyskinesia. The same levodopa treatment to normal rats, in which no dyskinesia was observed, also induced enlargement of dendritic spines, but not a decrease in density of spines in the direct pathway neurons. These results suggest that a loss and enlargement of dendritic spines in the direct pathway neurons plays important roles in the development of levodopa‐induced dyskinesia. © 2014 International Parkinson and Movement Disorder Society
Simultaneous functional MRI acquisition of distributed brain regions with high temporal resolution using a 2D‐selective radiofrequency excitation
Authors: Finsterbusch Jürgen
Published: February 2014

Purpose

To perform simultaneous functional MRI of multiple, distributed brain regions at high temporal resolution using a 2D‐selective radiofrequency (2DRF) excitation.

Methods

A tailored 2DRF excitation is used to excite several, small regions‐of‐interest distributed in the brain. They are acquired in a single projection image with an appropriately chosen orientation such that the different regions‐of‐interest can be discriminated by their position in the projection plane. Thus, they are excited and acquired simultaneously with a temporal resolution comparable to that of a single‐slice measurement. The feasibility of this approach for functional neuroimaging (in‐plane resolution 2 × 2 mm2) at high temporal resolution (80 ms) is demonstrated in healthy volunteers for regions‐of‐interest in the visual and motor system using checkerboard and finger tapping block‐design paradigms.

Results

Task‐related brain activation could be observed in both the visual and the motor system simultaneously with a high temporal resolution. For an onset shift of 240 ms for half of the checkerboard, a delay of the hemodynamic response in the corresponding hemisphere of the visual cortex could be detected.

Conclusion

Limiting the excited magnetization to the desired target regions with a 2DRF excitation reduces the imaging sampling requirements which can improve the temporal resolution significantly. Magn Reson Med 73:683–691, 2015. © 2014 Wiley Periodicals, Inc.
In situ vacuum exfoliation plus microwave curing: A facile and green technique for preparing polymeric composites with very good dispersion based on expanded graphite
Authors: Sun Yichen , Yuan Li , Liang Guozheng , Chang Jianfei , Gu Aijuan
Published: February 2014

Functional polymeric composites based on expanded graphite (EG) have obtained wide attentions worldwide owing to their great potential in many fields. Poor dispersion is the main problem limiting the full exploitation of outstanding properties of these composites. To solve the problem, a facile and green method, named as in situ vacuum exfoliation plus microwave curing (VEMC) technique, is developed. The biggest merit of the VEMC process is that worm‐like EG particles are directly used to prepare composites, and no solvent or other chemical is needed, so the chemical structure and original advantages of exfoliatable fillers can be fully utilized in the composites. A series of composites based on EG particles and epoxy (EP) resin, coded as new‐EG/EP, were fabricated using the VEMC technique. Interestingly, worm‐like EG particles are found to be in situ exfoliated into nanosheets, and these sheets are well dispersed in the resin. Compared with the composites prepared using traditional processes, new‐EG/EP composites have much higher dielectric constants, demonstrating that the VEMC technique is efficient to prepare composites with good dispersion based on exfoliatable fillers. POLYM. COMPOS., 36:385–388, 2015. © 2014 Society of Plastics Engineers
A randomized pilot trial of a telephone‐based couples intervention for physical intimacy and sexual concerns in colorectal cancer
Authors: Reese Jennifer Barsky , Porter Laura S. , Regan Katelyn R. , Keefe Francis J. , Azad Nilofer S. , Diaz Luis A. , Herman Joseph M. , Haythornthwaite Jennifer A.
Published: February 2014

Background

We previously developed and piloted a telephone‐based intimacy enhancement (IE) intervention addressing sexual concerns of colorectal cancer patients and their partners in an uncontrolled study. The current study tested the feasibility, acceptability, and preliminary efficacy of the IE intervention in a randomized, controlled trial.

Methods

Twenty‐three couples were randomized to either the four‐session IE condition or to a wait list control condition and completed sexual and relationship outcomes measures. The IE intervention teaches skills for coping with sexual concerns and improving intimacy. Feasibility and acceptability were assessed through enrollment and post‐treatment program evaluations, respectively. Effect sizes were calculated by comparing differences in average pre/post change scores across completers in the two groups (n = 18 couples).

Results

Recruitment and attrition data supported feasibility. Program evaluations for process (e.g., ease of participation) and content (e.g., relevance) demonstrated acceptability. Engaging in intimacy‐building activities and communication were the skills rated as most commonly practiced and most helpful. For patients, positive effects of the IE intervention were found for female and male sexual function, medical impact on sexual function, and self‐efficacy for enjoying intimacy (≥.58); no effects were found on sexual distress or intimacy and small negative effects for sexual communication, and two self‐efficacy items. For partners, positive IE effects were found for all outcomes; the largest were for sexual distress (.69), male sexual function (1.76), communication (.97), and two self‐efficacy items (≥.87).

Conclusions

The telephone‐based IE intervention shows promise for couples facing colorectal cancer. Larger multi‐site intervention studies are necessary to replicate findings. Copyright © 2014 John Wiley & Sons, Ltd.
Orientation of electron spins in hybrid ferromagnet–semiconductor nanostructures
Authors: Akimov I. A. , Korenev V. L. , Sapega V. F. , Langer L. , Zaitsev S. V. , Danilov Yu. A. , Yakovlev D. R. , Bayer M.
Published: February 2014

The spin orientation of electrons is studied in ferromagnet (FM)–semiconductor (SC) hybrid structures composed of a (Ga,Mn)As ferromagnetic layer, which is placed in the direct vicinity of a non‐magnetic SC quantum well (QW). It is shown that the polarization of carriers in the SC QW is achieved by spin‐dependent tunnelling into the magnetized ferromagnetic layer. This leads to dynamical spin polarization of the electrons, which can be directly observed by means of time‐resolved photoluminescence. We find that the electron spin polarization grows in time after excitation with an optical pulse and may reach values as large as 30%. The rate of spin‐dependent capture grows exponentially steeply with decreasing thickness of the spacer between ferromagnetic layer and QW, and it persists up to the Curie temperature of the (Ga,Mn)As layer. From time‐resolved pump–probe Kerr rotation data, we evaluate a value of only a few eV for the energy splitting between the electron Zeeman sublevels due to interaction with the ferromagnetic (Ga,Mn)As layer, indicating that the equilibrium spin polarization is negligible.

Schematic presentation of electron spin orientation in a semiconductor quantum well (QW) under linearly polarized excitation due to spin‐dependent capture of electrons in the ferromagnetic layer (FM). The arrows in the FM box indicate the orientation of the magnetization . The effect is detected by appearance of a circular polarization degree of photoluminescence after pulsed optical excitation (right). The data are shown for a spacer thickness of 5 nm.
Effect of Electrical Parameters on Type and Content of Non‐Metallic Inclusions after Electro‐Slag‐Remelting
Authors: Paar Armin , Schneider Reinhold , Zeller Peter , Reiter Gerhard , Paul Stefan , Würzinger Paul
Published: February 2014

This paper describes the effect of different electrical parameters on the type and content of non‐metallic‐inclusions in the ESR material X38CrMoV5‐1. For these investigations, six ingots were remelted with two DC polarities (cathodic and anodic) and with low frequency (1 Hz) AC power supplies under otherwise comparable remelting conditions, in an open laboratory ESR plant. The investigations included automated SEM‐analysis combined with EDX. The results show that the cleaning effect of both DC polarities is lower than the one with a low frequency AC power supply, whereas the cathodic DC polarity results in better cleanliness levels than the anodic one. In addition, the oxygen content of the ingots shows a strong increase when remelting with anodic DC polarity. A strong relation between the electric parameters and the types and sizes of inclusion of the ESR ingots could be found. The most pronounced differences occur with the oxide‐type inclusions. Thereby, the amount of the originally dominating (Al,Mg)‐spinel‐type‐oxides is further increased when remelting under DC− and AC conditions, but were rather eliminated in favor of Al2O3‐type inclusions when DC+ polarity is used. All oxysulfides, except Al‐oxysulfides, were strongly decreased or eliminated. Furthermore, a significant reduction of sulfides, especially CaS took place under all electrical parameters.
Internationalization as Interaction: A Process Perspective on Internationalization from a Small Developing Country
Authors: Williams Nigel L. , Ridgman Tom , Shi Yongjiang , Ferdinand Nicole
Published: February 2014

Despite their heavy dependence on international markets, small developing countries or small states have been underrepresented in the internationalization literature. Unlike developed or large developing countries, small states face dual constraints of relatively weak institutions and a narrow resource base along with an open market environment. A changing domestic environment in small states requires firms to adapt and a process approach was employed in order to examine sustained internationalization firms from Trinidad and Tobago (TT). Analysis of the findings indicates that changing economic circumstances result in varying domestic production and market resource availability. In response, firms from small states may engage in phased rather than staged patterns of activity that include accelerated, reverse, and inward internationalization. © 2014 Wiley Periodicals, Inc.
The Big Family: Informal Financing of Small‐ and Medium‐Sized Businesses by Guanxi
Authors: Sheng Hsia Hua , Mendes‐Da‐Silva Wesley
Published: February 2014

Guanxi facilitates interaction between companies and people in Confucian societies. Does this type of social construct still play the key role, when the entrepreneurs live in Western societies? The objective of this article is to verify the impact of Guanxi on the capacity of small and medium‐sized businesses accessing financial resources informally. To this end, data collected from small Chinese entrepreneurs active in the principal business center of Brazil were used. From nonparametric tests, the results suggest that: (1) different levels of Guanxi allow small and medium‐sized businesses to access informal financial resources; (2) different types of informal financing are mostly used, or judged to be more significant, depending on the level of Guanxi of the entrepreneur in terms of parental and nonfamily ties; and (3) unlike the Western literature on the financial cycles of start‐ups, this type of informal financing can extend beyond the initial stage of the business. © 2014 Wiley Periodicals, Inc.
Nrf2 protects the lung against inflammation induced by titanium dioxide nanoparticles: A positive regulator role of Nrf2 on cytokine release
Authors: Delgado‐Buenrostro Norma L. , Medina‐Reyes Estefany I. , Lastres‐Becker Isabel , Freyre‐Fonseca Verónica , Ji Zhaoxia , Hernández‐Pando Rogelio , Marquina Brenda , Pedraza‐Chaverri José , Espada Sandra , Cuadrado Antonio , Chirino Yolanda I.
Published: February 2014

Titanium dioxide nanoparticles (TiO2NPs) have been classified as possibly carcinogenic to humans and they are an important nanomaterial widely used in pharmaceutical and paint industries. Inhalation is one of the most important routes of exposure in occupational settings. Several experimental models have shown that oxidative stress and inflammation are key mediators of cell damage. In this regard, Nrf2 modulates cytoprotection against oxidative stress and inflammation, however, its role in inflammation induced by TiO2NPs exposure has been less investigated. The aim of this work was to investigate the role of Nrf2 in the cytokines produced after 4 weeks of TiO2NPs exposure (5 mg/kg/2 days/week) using wild‐type and Nrf2 knockout C57bl6 mice. Results showed that Nrf2 protects against inflammation and oxidative damage induced by TiO2NPs exposure, however, Nrf2 is a positive mediator in the expression of IFN‐γ, TNF‐α, and TGF‐β in bronchial epithelium and alveolar space after 4 weeks of exposure. These results suggest that Nrf2 has a central role in up‐regulation of cytokines released during inflammation induced by TiO2NPs and those cytokines are needed to cope with histological alterations in lung tissue. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 782–792, 2015.
Long-Term Outcomes following Single-Portal Endoscopic Carpal Tunnel Release
Authors: Means K. R. , Dubin N. H. , Patel K. M. , Pletka J. D.
Published: February 2014

Background

There is limited published information about long-term outcomes and recurrence rates following ***single-portal endoscopic carpal tunnel release.

Methods

We reviewed symptom and function outcomes from a prospectively collected database of patients who underwent single-portal endoscopic carpal tunnel release at a minimum of 8 years follow-up. Out of 207 patients in the original database, we were able to confirm correct current contact information for 106 patients. Of these, 91 patients with 115 single-portal endoscopic carpal tunnel releases agreed to participate. All of these patients were eligible for this long-term follow-up study based on documented preoperative and 6-month postoperative Levine-Katz questionnaire scores. Patients then completed a current update of the Levine-Katz questionnaires to assess function and symptom outcomes at latest follow-up.

Results

The average 6-month postoperative scores were significantly lower compared with the average preoperative scores and were maintained at long-term follow-up. There were no significant differences in average change in scores at long-term follow-up compared to 6-months postoperative.

Conclusions

Single-portal endoscopic carpal tunnel release is an effective surgical treatment for carpal tunnel syndrome. Low recurrence rates and maintenance of low symptom and function scores can be expected at 8 to 10 years following this technique.
On the beta-expansions of 1 and algebraic numbers for a Salem number beta
Authors: KANEKO HAJIME
Published: February 2014

We study the digits of $\beta $-expansions in the case where $\beta $ is a Salem number. We introduce new upper bounds for the numbers of occurrences of consecutive 0s in the expansion of 1. We also give lower bounds for the numbers of non-zero digits in the $\beta $-expansions of algebraic numbers. As applications, we give criteria for transcendence of the values of power series at certain algebraic points.
DNS of a turbulent boundary layer with surface roughness
Authors: Cardillo James , Chen Yi , Araya Guillermo , Newman Jensen , Jansen Kenneth , Castillo Luciano
Published: February 2014

A pioneer direct numerical simulation (DNS) of a turbulent boundary layer at $R{e}_{\theta } = 2077{{\unicode{x2013}}}2439$, was performed, on a rough surface and with a zero pressure gradient (ZPG). The boundary layer was subjected to transitional, 24-grit sandpaper surface roughness, with a roughness parameter of ${k}^{+ } \simeq 11$. The computational method involves a synergy of the dynamic multi-scale approach devised by Araya et al. (2011) for prescribing inlet turbulent boundary conditions and a new methodology for mapping high-resolution topographical surface data into a computational fluid dynamics (CFD) environment. It is shown here that the dynamic multi-scale approach can be successfully extended to simulations which incorporate surface roughness. The DNS results demonstrate good agreement with the laser Doppler anemometry (LDA) measurements performed by Brzek et al. (2008) and Schultz & Flack (2003) under similar conditions in terms of mean velocity profiles, Reynolds stresses and flow parameters, such as the skin friction coefficient, boundary and momentum thicknesses. Further, it is demonstrated that the effects of the surface roughness on the Reynolds stresses, at the values of $R{e}_{\theta } = 2077{{\unicode{x2013}}}2439$, are scale-dependent. Roughness effects were mainly manifested up to $y/ \delta \approx 0. 1$. Generally speaking, it was observed that inner peak values of Reynolds stresses increased when considering outer units. However, decreases were seen in inner units. In the outer region, the most significant differences between the present DNS smooth and rough cases were computed in the wall-normal component $\langle {v}^{\prime 2} \rangle $ of the Reynolds stresses and in the Reynolds shear stresses $\langle {u}^{\prime } {v}^{\prime } \rangle $ in outer units. From the resulting flow fields a proper orthogonal decomposition (POD) analysis is performed and the effects of the surface roughness are distinctly observed in the most energetic POD modes. The POD analysis shows that the surface roughness causes a redistribution of the kinetic energy amongst the POD modes with energy being shifted from low-order to high-order modes in the rough case versus the smooth case. Also, the roughness causes a marked decrease in the characteristic wavelengths observed in the POD modes, particularly in the streamwise component of the velocity field. Low-order modes of the streamwise component demonstrated characteristic wavelengths of the order of $3\delta $ in the smooth case, whereas the same modes for the rough case demonstrated characteristic wavelengths of only $\delta $.
Efficacy and safety of inferior turbinates coblation in children
Authors: Bitar M A , Kanaan A A , Sinno S
Published: February 2014

Objective:

To assess the effectiveness and safety of coblation in relieving inferior turbinate hypertrophy in children.

Methods:

An observational cohort study was undertaken. The severity of allergic rhinitis and the severity and degree of nasal obstruction were assessed using subjective and clinical symptom grading tools, a visual analogue scale, and endoscopy. Any post-operative complications were noted at 1 week, and at 1, 3, 6 and 12 months post-operatively. Data from extended follow-up periods were included when available. The statistical significance of changes in parameter values was assessed using the Wilcoxon signed-rank test.

Results:

Thirty-two patients were recruited (mean age, 11.28 years; range, 6–17 years). Significant post-operative improvement (p < 0.001) was noted in the severity and degree of nasal obstruction. This improvement was maintained after a mean follow-up period of 10.5 months (range, 1 month to 4 years). No mucosal ulceration or adhesion was encountered. Minimal crusting was noted in 8.57 per cent of patients at 1-week follow up. Allergic rhinitis symptoms improved significantly.

Conclusion:

Inferior turbinate reduction by coblation is an effective and safe procedure in children aged six years and older. The positive outcomes seem to be long-lasting.
Reduced gray matter volume in the anterior cingulate, orbitofrontal cortex and thalamus as a function of mild depressive symptoms: a voxel-based morphometric analysis
Authors: Webb C. A. , Weber M. , Mundy E. A. , Killgore W. D. S.
Published: February 2014

Background

Studies investigating structural brain abnormalities in depression have typically employed a categorical rather than dimensional approach to depression [i.e. comparing subjects with Diagnostic and Statistical Manual of Mental Disorders (DSM)-defined major depressive disorder (MDD)v. healthy controls]. The National Institute of Mental Health, through their Research Domain Criteria initiative, has encouraged a dimensional approach to the study of psychopathology as opposed to an over-reliance on categorical (e.g. DSM-based) diagnostic approaches. Moreover, subthreshold levels of depressive symptoms (i.e. severity levels below DSM criteria) have been found to be associated with a range of negative outcomes, yet have been relatively neglected in neuroimaging research.

Method

To examine the extent to which depressive symptoms – even at subclinical levels – are linearly related to gray matter volume reductions in theoretically important brain regions, we employed whole-brain voxel-based morphometry in a sample of 54 participants.

Results

The severity of mild depressive symptoms, even in a subclinical population, was associated with reduced gray matter volume in the orbitofrontal cortex, anterior cingulate, thalamus, superior temporal gyrus/temporal pole and superior frontal gyrus. A conjunction analysis revealed concordance across two separate measures of depression.

Conclusions

Reduced gray matter volume in theoretically important brain regions can be observed even in a sample that does not meet DSM criteria for MDD, but who nevertheless report relatively elevated levels of depressive symptoms. Overall, these findings highlight the need for additional research using dimensional conceptual and analytic approaches, as well as further investigation of subclinical populations.
Mapping collective behavior in the big-data era
Authors: Bentley R. Alexander , O'Brien Michael J. , Brock William A.
Published: February 2014

The behavioral sciences have flourished by studying how traditional and/or rational behavior has been governed throughout most of human history by relatively well-informed individual and social learning. In the online age, however, social phenomena can occur with unprecedented scale and unpredictability, and individuals have access to social connections never before possible. Similarly, behavioral scientists now have access to “big data” sets – those from Twitter and Facebook, for example – that did not exist a few years ago. Studies of human dynamics based on these data sets are novel and exciting but, if not placed in context, can foster the misconception that mass-scale online behavior is all we need to understand, for example, how humans make decisions. To overcome that misconception, we draw on the field of discrete-choice theory to create a multiscale comparative “map” that, like a principal-components representation, captures the essence of decision making along two axes: (1) aneast–westdimension that represents the degree to which an agent makes a decision independently versus one that is socially influenced, and (2) anorth–south dimensionthat represents the degree to which there is transparency in the payoffs and risks associated with the decisions agents make. We divide the map into quadrants, each of which features a signature behavioral pattern. When taken together, the map and its signatures provide an easily understood empirical framework for evaluating how modern collective behavior may be changing in the digital age, including whether behavior is becoming more individualistic, as people seek out exactly what they want, or more social, as people become more inextricably linked, even “herdlike,” in their decision making. We believe the map will lead to many new testable hypotheses concerning human behavior as well as to similar applications throughout the social sciences.
An addition to Kurzban et al.'s model: Thoroughness of cost-benefit analyses depends on the executive tasks at hand
Authors: Bruyneel Sabrina D. , Dewitte Siegfried
Published: February 2014

Though Kurzban et al.'s model explains a considerable set of empirical findings, it cannot accommodate other results without relying on extra assumptions. We offer an addition to the model, and suggest that cost-benefit analyses themselves depend on executive function, and therefore can be biased. The adapted model allows for explaining depletion effects, as well as their reversals, documented in the literature.
On treating effort as a dynamically varying cost input
Authors: Hofmann Wilhelm , Kotabe Hiroki
Published: February 2014

Kurzban et al.'s framework may be extended in fruitful ways by treating effort also as a cost input that affects the utility computation of a given option (rather than only as the output of a utility comparison between options). The weight people assign to effort as a cost may vary dynamically as a function of situational and dispositional factors.
Opportunity prioritization, biofunctional simultaneity, and psychological mutual exclusion
Authors: Iran-Nejad Asghar , Zengaro Sally Ann
Published: February 2014

We argue that prioritization, simultaneity, and mutual exclusion are mind-body integration functions that can't be addressed meaningfully at the psychological (computational) level alone. We describe the outlook for an integration between Kurzban et al.'s profound discussion of opportunity cost/benefit prioritization and decades of related development in biofunctional science.
An expanded perspective on the role of effort phenomenology in motivation and performance
Authors: Molden Daniel C.
Published: February 2014

Kurzban and colleagues propose that experiences of effort alter motivations to persist during goal pursuit by highlighting costs of persistence. I expand this proposal by discussing how effort experiences (a) not only influence, but can be influenced by motivations to persist on a goal; and (b) not only highlight costs that undermine persistence, but can also signal progress and increase persistence.
Effort aversiveness may be functional, but does it reflect opportunity cost?
Authors: Navon David
Published: February 2014

Though the aversiveness of effort may indeed serve in selecting tasks for executive attention, the notion that it reflects opportunity costs is questionable: The potency of distractions in real-life situations is not regularly related with the potential benefit from attending to them.
Mental effort and fatigue as consequences of monotony
Authors: Prudkov Pavel N.
Published: February 2014

Kurzban et al. associate mental effort and fatigue with a hypothetical mechanism able to estimate the utilities of possible actions and then select the action with a maximal utility. However, this approach faces fundamental problems. In my opinion, mental effort and fatigue are results of a conflict between the monotony of long-term activities and the novelty-processing systems.
Subjective effort derives from a neurological monitor of performance costs and physiological resources
Authors: Tops Mattie , Boksem Maarten A. S. , Koole Sander L.
Published: February 2014

Kurzban et al.'s expectancy-value mechanism of effort allocation seems relevant in situations when familiar tasks are initiated. However, we think additional mechanisms are important when people continue with a task for a prolonged time. These mechanisms, which are particularly relevant for performance of novel or urgent tasks, involve neural systems that track performance costs and resources.
Effort processes in achieving performance outcomes: Interrelations among and roles of core constructs
Authors: Wright Rex A. , Pantaleo Giuseppe
Published: February 2014

We address points of confusion pertaining to interrelations among and roles of core constructs involved in the production of performance outcomes. We do so informed by the body of work derived from Brehm's seminal motivation intensity theory – in particular an elaboration from the theory concerned with fatigue influence on effort and associated cardiovascular responses in people confronted with performance challenges.
Persistence: What does research on self-regulation and delay of gratification have to say?
Authors: Zayas Vivian , Günaydin Gül , Pandey Gayathri
Published: February 2014

Despite the simplicity of Kurzban et al.'s framework, we argue that important information is lost in their simplification. We discuss research on delay of gratification and self-regulation that identifies key situational and psychological factors affecting how people represent rewards and costs. These factors affect the expected utilities of behavioral options and thus dramatically influence whether individuals persist on a difficult task.