bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling root reinforcement using a root-failure Weibull survival function
Authors: Schwarz M. , Giadrossich F. , Cohen D.
Published: November 2013

Abstract. Root networks contribute to slope stability through complex interactions with soil that include mechanical compression and tension. Due to the spatial heterogeneity of root distribution and the dynamics of root turnover, the quantification of root reinforcement on steep slopes is challenging and consequently the calculation of slope stability also. Although considerable progress has been made, some important aspects of root mechanics remain neglected. In this study we address specifically the role of root-strength variability on the mechanical behavior of a root bundle. Many factors contribute to the variability of root mechanical properties even within a single class of diameter. This work presents a new approach for quantifying root reinforcement that considers the variability of mechanical properties of each root diameter class. Using the data of laboratory tensile tests and field pullout tests, we calibrate the parameters of the Weibull survival function to implement the variability of root strength in a numerical model for the calculation of root reinforcement (RBMw). The results show that, for both laboratory and field data sets, the parameters of the Weibull distribution may be considered constant with the exponent equal to 2 and the normalized failure displacement equal to 1. Moreover, the results show that the variability of root strength in each root diameter class has a major influence on the behavior of a root bundle with important implications when considering different approaches in slope stability calculation. Sensitivity analysis shows that the calibration of the equations of the tensile force, the elasticity of the roots, and the root distribution are the most important steps. The new model allows the characterization of root reinforcement in terms of maximum pullout force, stiffness, and energy. Moreover, it simplifies the implementation of root reinforcement in slope stability models. The realistic quantification of root reinforcement for tensile, shear and compression behavior allows for the consideration of the stabilization effects of root networks on steep slopes and the influence that this has on the triggering of shallow landslides.
Precipitation bias correction of very high resolution regional climate models
Authors: Argüeso D. , Evans J. P. , Fita L.
Published: November 2013

Abstract. Regional climate models are prone to biases in precipitation that are problematic for use in impact models such as hydrology models. A large number of methods have already been proposed aimed at correcting various moments of the rainfall distribution. They all require that the model produce the same or a higher number of rain days than the observational data sets, which are usually gridded data sets. Models have traditionally met this condition because their spatial resolution was coarser than the observational grids. But recent climate simulations use higher resolution and the models are likely to systematically produce fewer rain days than the gridded observations. In this study, model outputs from a simulation at 2 km resolution are compared with gridded and in situ observational data sets to determine whether the new scenario calls for revised methodologies. The gridded observations are found to be inadequate to correct the high-resolution model at daily timescales, because they are subjected to too frequent low intensity precipitation due to spatial averaging. A histogram equalisation bias correction method was adapted to the use of station, alleviating the problems associated with relative low-resolution observational grids. The wet-day frequency condition might not be satisfied for extremely dry biases, but the proposed approach substantially increases the applicability of bias correction to high-resolution models. The method is efficient at bias correcting both seasonal and daily characteristic of precipitation, providing more accurate information that is crucial for impact assessment studies.
Predicting freakish sea state with an operational third generation wave model
Authors: Waseda T. , In K. , Kiyomatsu K. , Tamura H. , Miyazawa Y. , Iyama K.
Published: November 2013

Abstract. Understanding of freak wave generation mechanism has advanced and the community has reached to a consensus that spectral geometry plays an important role. Numerous marine accident cases were studied and revealed that the narrowing of the directional spectrum is a good indicator of dangerous sea. However, the estimation of the directional spectrum depends on the performance of the third generation wave model. In this work, a well-studied marine accident case in Japan in 1980 (Onomichi–Maru incident) is revisited and the sea states are hind-casted using both the DIA and SRIAM nonlinear source terms. The result indicates that the temporal evolution of the basic parameters (directional spreading and frequency bandwidth) agree reasonably well between the two schemes and therefore most commonly used DIA method is qualitatively sufficient to predict freakish sea state. The analyses revealed that in the case of Onomichi–Maru, a moving gale system caused the spectrum to grow in energy with limited down-shifting at the accident site. This conclusion contradicts the marine inquiry report speculating that the two swell systems crossed at the accident site. The unimodal wave system grew under strong influence of local wind with a peculiar energy transfer.
Parameter and state estimation with a time-dependent adjoint marine ice sheet model
Authors: Goldberg D. N. , Heimbach P.
Published: November 2013

Abstract. To date, assimilation of observations into large-scale ice models has consisted predominantly of time-independent inversions of surface velocities for basal traction, bed elevation, or ice stiffness, and has relied primarily on analytically derived adjoints of glaciological stress balance models. To overcome limitations of such "snapshot" inversions – i.e., their inability to assimilate time-dependent data for the purpose of constraining transient flow states, or to produce initial states with minimum artificial drift and suitable for time-dependent simulations – we have developed an adjoint of a time-dependent parallel glaciological flow model. The model implements a hybrid shallow shelf–shallow ice stress balance, solves the continuity equation for ice thickness evolution, and can represent the floating, fast-sliding, and frozen bed regimes of a marine ice sheet. The adjoint is generated by a combination of analytic methods and the use of algorithmic differentiation (AD) software. Several experiments are carried out with idealized geometries and synthetic observations, including inversion of time-dependent surface elevations for past thicknesses, and simultaneous retrieval of basal traction and topography from surface data. Flexible generation of the adjoint for a range of independent uncertain variables is exemplified through sensitivity calculations of grounded ice volume to changes in basal melting of floating and basal sliding of grounded ice. The results are encouraging and suggest the feasibility, using real observations, of improved ice sheet state estimation and comprehensive transient sensitivity assessments.
An Estimation of the Contribution of the International Meeting Industry to the Korean National Economy Based on Input—Output Analysis
Authors: Kim Dae-Kwan , Kim Hak-Jun , Lee Sang-Min , Choe Yeongbae , Song Soo-Yeop
Published: November 2013

This paper presents the contribution of the international meeting industry to the Korean national economy. To obtain more accurate results, the study adopted three improvements over previous research: consideration of both supply and demand; direct expenditure surveys of participants and hosts; and re-categorization of related business sectors. The results of the input-output analysis showed that per capita expenditure for international and domestic participants was US$2,432.4 and US$459.3, respectively, and the per capita average budget was US$562.1. Based on these findings, the total contribution of the international meeting industry to the Korean economy exceeds US$1,343.2 million in output, US$236.6 million in personal income, US$589.3 million in value added, US$61.5 million in tax revenue and 16,336 full-time-equivalent jobs. These results provide two key implications, providing evidence of the importance of both the supply and demand sides and the relative importance of each sub-industry for increasing economic benefit.
Japanese Aesthetic Influences on Early 20th-Century Art Education: Arthur Wesley Dow and Ernest Fenollosa
Authors: Williams Betty Lou
Published: November 2013

Incorporating primary archival materials, this essay considers the influence of Arthur Wesley Dow on art education in the United States at the turn of the 20th century. I also highlight the impact of Dow’s teacher and mentor, Ernest Fenollosa. I posit here that their relationship resulted in the introduction and influence of Japanese aesthetics, which in turn shaped Dow’s views about the elements and principles of art and design. My essay chronicles how some of Dows’ aesthetic understandings were shaped and then disseminated into U.S. art education, art history, and training for artists from the late 1800s through the first half of the 1900s.
Alteração experimental de rochas carbonáticas, Caverna das Pérolas, Iporanga (SP)
Authors: SHINZATO Mirian Chieko , HYPOLITO Raphael , BARBIERI Alex José , CARVALHO Flavio Machado de Souza
Published: November 2013

Trabalhos experimentais foram realizados com o intuito de estudar a alteração química em rochas carbonáticas provenientes da Caverna das Pérolas, Município de Iporanga, Estado de São Paulo. Extratores soxhlet foram utilizados para acelerar o processo de lixiviação de duas formas: contínua e intermitente. A solução de lixiviação obtida no ensaio contínuo foi analisada quimicamente no final do período de lixiviação (cerca de 454 horas), enquanto os precipitados foram separados e analisados mineralogicamente por difração de raios X (DRX). No ensaio de alteração intermitente, as soluções foram recolhidas após períodos pré-determinados e analisados quimicamente junto com os precipitados, para determinar o total de íons remobilizados da rocha alterada. A composição química das rochas alteradas experimentalmente também foi analisada e comparada com a da rocha sã, a partir das frações molares de seus constituintes maiores. Verificou-se que os principais íons lixiviados no início do processo de alteração foram Na+ e Mg2+; no entanto, com o aumento da alteração química, os íons Sr2+, Ba2+ e Ca2+ passaram a ser, juntamente com o Na+, os íons mais remobilizados, dando início também à precipitação de calcita. Observou-se que no experimento contínuo as concentrações de Sr2+ e Ba2+ ficaram inferiores em relação ao experimento intermitente, revelando que esses íons possivelmente co-precipitaram com a calcita. A baixa razão Mg/Ca pode ter promovido a precipitação preferencial da calcita, em relação à aragonita, nas soluções de alteração experimental. Verificou-se que houve maior taxa de remobilização dos constituintes da rocha carbonática na zona em que as amostras foram submetidas a flutuações do nível freático no compartimento do soxhlet. Entre os minerais secundários observados na rocha alterada, destaca-se a caulinita.
A erosividade das chuvas nos planaltos cársticos do Vale do Rio Betari, Iporanga (SP)
Authors: FERRARI José Antonio , AMARAL Rosângela do , ARMANI Gustavo , HIRUMA Silvio Takashi
Published: November 2013

Neste trabalho são apresentadas as primeiras estimativas da erosividade das chuvas (EI30) nos planaltos cársticos da bacia do Rio Betari, obtidas a partir da análise de séries pluviográficas. Os resultados possibilitaram ajustar um modelo probabilístico para avaliar a ocorrência de eventos erosivos, bem como estabelecer modelos locais simplificados para o cálculo de EI30 a partir do coeficiente de chuva (RC). Os valores de EI30 mostraram-se inferiores aos estimados pelo modelo tradicionalmente empregado para se inferir a erosividade no Estado de São Paulo.
Sulfatos secundários de Itaquaquecetuba, Estado de São Paulo
Authors: ATENCIO Daniel , HYPOLITO Raphael
Published: November 2013

Os sulfetos de ferro pirita e marcassita ocorrem como cimento em rochas sedimentares da Formação Itaquaquecetuba, no município homônimo, Estado de São Paulo. A exposição destes minerais a condições oxidantes provoca a formação de soluções ácidas de sulfato de ferro que atacam feldspatos, micas e outros minerais, enriquecendo-se em potássio, sódio, cálcio, alumínio e magnésio. A partir dessas soluções precipitam sulfatos contendo esses cátions. Estudos mineralógicos permitiram a identificação dos sulfatos melanterita, rozenita, coquimbita, metavoltina, alunogênio, epsomita e gipsita, bem como minerais dos grupos da halotriquita, copiapita e alunita. Várias transformações mineralógicas ocorreram após a coleta das amostras, incluindo a formação de materiais não observados nos afloramentos de Itaquaquecetuba, como römerita, paracoquimbita e um sulfato de ferro amorfo. O hábito de minerais e agregados - crostas, agregados sacaroidais ou fibrosos e estalactites - reflete cristalização rápida. A sequência de formação dos sulfatos de Itaquaquecetuba é a seguinte: 1) sulfatos hidratados de ferro (II); 2) sulfatos hidratados de ferro (II), ferro (III) e outros cátions; 3) hidroxissulfatos hidratados de ferro (III) e outros cátions. Após esta etapa, duas linhagens divergentes são aparentes, uma com a formação de sulfatos hidratados de ferro (III) e outra com a formação de hidroxissulfatos de ferro (III), eventualmente com outros cátions. A etapa final da alteração produz goethita.
Can Bio-Based Thermoset Polymers Replace Petrochemical Based Counterparts?
Authors: Adekunle Kayode Feyisetan
Published: November 2013

Specific answers are required for purpose of better communication with many researchers, manufacturers, and users of polymer worldwide. This paper posted so many questions about the research activities on bio-based/ renewable thermoset polymers as against petrochemical based thermoset polymers. Quite a few answers were given but the remaining unanswered questions will surely be required in order to better understand the results achieved in this research area.
Modification and Characterization of Biodegradable Chitosan/ Starch-Based Films with Monomer 1,4-Butanediol Diacrylate (BDDA) by Gamma Radiation
Authors: Akter Nousin , Saha Suvanker , Hossain Farah M.J. , Quader Fahad B. , Alamgir Poonam , Khan Ruhul A.
Published: November 2013

Chitosan reinforced starch-based biodegradable films were prepared by solution casting. Tensile strength (TS), tensile modulus (TM), elongation at break (%), and water vapor permeability (WVP) of the 50% chitosan containing starch-based films were found to be 47 MPa, 550 MPa, 16%, and 2.45 g·mm/m2·day·kPa, respectively. Monomer 1,4 butanediol diacrylate (BDDA) was added (0.25-1% by wt) to the starch/chitosan (50:50) based film formulation. Then, films were cast and gamma irradiated from a radiation dose varied from 1 kGy to 25 kGy. Then mechanical and barrier properties were evaluated. The highest TS (80 MPa) and TM (880 MPa) of the films were found by using 0.5% monomer at 5 kGy dose. The WVP of the films were found to be 1.50 g·mm/m2·day·kPa which is 38.77% lower than control starch/chitosan-based films. Molecular interactions due to incorporation of BDDA were supported by Fourier transform infra red (FTIR) spectroscopy. The water uptake of the films pointed out better hydrophobic character due to incorporation of BDDA in starch/chitosan-based films. Surface morphologies of BDDA treated films were examined by scanning electron microscope (SEM) and suggested better morphologies due to BDDA treatment with starch/chitosan-based biodegradable films.
Three-Dimensional Simulation of the Shrinkage Behavior of Injection-Molded Poly Lactic Acid (PLA): Effects of Temperature, Shear Rate and Part Thickness
Authors: Guo Wenhe , Yang Bin , Xia Ru , Su Lifen , Miao Jibin , Qian Jiasheng , Chen Peng , Yu Xuekang , Zhang Qianlei , Deng Shuangquan
Published: November 2013

The effects of injection temperature, shear and part thickness on the linear shrinkage of injection-molded poly (lactic acid) (PLA) were intensively analyzed using the Autodesk Moldflow software. The obtained results showed that both melt temperature and shear rate had obvious effects on the linear shrinkage of PLA, i.e., the linear shrinkage of PLA increases significantly with the increase of melt temperature and shear rate. In addition, the shrinkage of high-crystallinity PLA was remarkably larger than that of low-crystallinity PLA, and thin-walled parts was larger than thick-walled ones in shrinkage.
Computational Simulation of the Random Depolymerization of Linear Polymers Obtained by Step-Polymerization of AB-type Monomers
Authors: López Floralba , Rangel Geraldine , Uzcategui Mayerlin , Velásquez Cristóbal Lárez
Published: November 2013

This paper presents evaluation results of a computational algorithm developed to simulate the random depolymerization process of a linear polymer having an initial distribution of molecular weights similar to polymers obtained by polycondensation of AB-type monomers, i.e., Flory-Schultz or most probable distribution. Starting from fundamental definitions of this system, as the initial values of the degree of polymerization and chain number (Xno and No, respectively) and the percentage of cleaved bonds (%E), it is confirmed that our algorithm adequately describes the random depolymerization process. Results obtained during the computational simulation indicate that the algorithm properly predicts, among other things, that the inverse of the final polymerization degree (1/Xnf) increases linearly with the applied %E while polydispersity after depolymerization (Df) decreases linearly when the latter parameter increases.
Réécriture de la figure mythique d’Ulysse dans Ulysse from Bagdad d’Éric-Emmanuel Schmitt
Authors: Cauville Joëlle
Published: November 2013

Dans Ulysse from Bagdad, Éric-Emmanuel Schmitt fait appel consciemment au mythe : il fait le pari d’ennoblir son personnage, l’immigré clandestin irakien, Saad Saad en le plongeant dans un voyage comparable à celui d’Ulysse dans l’Odyssée. Toutefois le périple d’Ulysse est un voyage de retour tandis que celui de Saad est celui de tous les départs. Là n’est pas la seule entorse que l’écrivain contemporain fait au texte matriciel. En analysant cette réécriture originale du célèbre mythe, on s’apercevra que, par le ton parodique de son roman, Schmitt est aussi l’héritier de Giraudoux. Nous conclurons que l’humour de Schmitt, sa verve de conteur et son recours à la grande épopée homérique ne nous détournent pas du sérieux de la condition de Saad Saad, ils nous permettent paradoxalement d’en mesurer la gravité.
Understanding the Behavior of Filipino Twitter Users during Disaster
Authors: Lee Boaz John , Ybañez Michael , De Leon Marlene M. , Estuar Ma. Regina E.
Published: November 2013

The Philippines is a country that frequently experiences disasters, such as typhoons. During these events, many citizens spread information and communicate with each other through social media like Twitter. This study aims to take advantage of that fact by analyzing the data from social media to get some insights on the situation. Specifically, this paper studies the behavior of Filipinos on Twitter during a disaster, and tries to see the differences between participants, or the direct victims of the disaster, and observers. The study used Latent Dirichlet Allocation and Principal Component Analysis to extract the different topics discussed during a disaster, and found out which topics participants are more likely to talk about. Results also show which topics are more likely to be retweeted, which language participants in disaster use more often, and what emotions are present in the disaster-time tweets of Filipinos.
Real-time strategy games bot based on a nonsimultaneous human-like movement characteristic
Authors: Novak Damijan , Verber Domen
Published: November 2013

This paper discusses how to improve the behaviour of artificial intelligence (AI) algorithms during real-time strategy games so as to behave more like human players. If we want to achieve this goal we must take into consideration several aspects of human psychology – human characteristics. Here we focused on the limited reaction times of the players in contrast to the enormous speed of modern computers. We propose an approach that mimics the limitations of the human reaction times. In order to work properly, the AI must know the average reaction times of the players. Some techniques and proposed algorithm outline are presented on how to achieve this.
A Highly Robust Audio Monitoring System for Radio Broadcasting
Authors: Nishan E.D. , Senevirathna W. , Jayaratne K.L.
Published: November 2013

Proposing a novel approach for monitoring songs for the radio broadcasting channels is very important for the interest of singers, writers and musicians in the musical industry. Singers, writers and musicians have a claim to intellectual property rights for their songs broadcast over all the radio channels. According to this intellectual property rights act singers, writers and musicians should be paid for their songs broadcast over all the radio channels. Therefore we propose a real time audio monitoring approach to solve this problem which includes our own audio recognition algorithm. It is easy to recognize a song, when you provide the original high quality blueprint of the song as input. But we can’t expect such kind of audio input from radio channels since lots of transformations are possible before reaching the end user or listener. For example, adding environmental effects such as noise, adding commercials on the song as watermarks, playing more than one song as a chain without adding any silence between them, playing a part of the song, playing same song in various speeds and so on. These transformations cause change in the uniqueness of particular song and make the problem even more difficult. The algorithm we proposing is resistant to noise and distortion as well as it is capable of recognizing short segment of song when broadcasting over the radio channels. At the end of the processing our system generates a descriptive report including title of the song, singer of the song, writer of the song, composer of the song, number of times it was played and when it was played for all songs for a particular period for all radio broadcasting channels. We evaluate our system against various types of real time scenarios and achieved overall higher level of accuracy (96%) at the end.
Enhanced cross‐shelf exchange by tides in the western Ross Sea
Authors: Wang Q. , Danilov S. , Hellmer H. , Sidorenko D. , Schröter J. , Jung T.
Published: November 2013

The western Ross Sea is one of the key sites for cross‐shelf water exchange around Antarctica. The mechanism through which tides affect the cross‐shelf exchange in the northwestern Ross Sea is investigated using numerical simulations. Tides are found to increase the high‐salinity shelf water (HSSW) outflow through the impact on the warm water intrusion of open ocean origin. The residual tidal currents are onshore along the Modified Circumpolar Deep Water pathway and therefore enhance its intrusion. Lighter ambient water adjacent to the HSSW increases the cross‐flow density gradient, thus strengthening the HSSW export. At the same time, the onshore residual current and increased dilution of the HSSW have the potential to reduce the export rate. Owing to the existence of opposite tidal effects, the strongest HSSW export happens at the intermediate tidal forcing strength. The amplification of tides on cross‐shelf exchange indicates that the relevant dynamical processes should be simulated or parameterized in climate models in order to adequately predict the ocean.
Azimuthal directions of equatorial noise propagation determined using 10 years of data from the Cluster spacecraft
Authors: Němec F. , Santolík O. , Pickett J. S. , Hrbáčková Z. , Cornilleau‐Wehrlin N.
Published: November 2013

Equatorial noise (EN) emissions are electromagnetic waves at frequencies between the proton cyclotron frequency and the lower hybrid frequency routinely observed within a few degrees of the geomagnetic equator at radial distances from about 2 to 6 RE. They propagate in the extraordinary (fast magnetosonic) mode nearly perpendicularly to the ambient magnetic field. We conduct a systematic analysis of azimuthal directions of wave propagation, using all available Cluster data from 2001 to 2010. Altogether, combined measurements of the Wide‐Band Data and Spectrum Analyzer of the Spatio‐Temporal Analysis of Field Fluctuations instruments allowed us to determine azimuthal angle of wave propagation for more than 100 EN events. It is found that the observed propagation pattern is mostly related to the plasmapause location. While principally isotropic azimuthal directions of EN propagation were detected inside the plasmasphere, wave propagation in the plasma trough was predominantly found directed to the West or East, perpendicular to the radial direction. The observed propagation pattern can be explained using a simple propagation analysis, assuming that the emissions are generated close to the plasmapause.
Investigation of ionospheric stimulated Brillouin scatter generated at pump frequencies near electron gyroharmonics
Authors: Mahmoudian A. , Scales W. A. , Bernhardt P. A. , Fu H. , Briczinski S. J. , McCarrick M. J.
Published: November 2013

Stimulated Electromagnetic Emissions (SEEs), secondary electromagnetic waves excited by high power electromagnetic waves transmitted into the ionosphere, produced by the Magnetized Stimulated Brillouin Scatter (MSBS) process are investigated. Data from four recent research campaigns at the High Frequency Active Auroral Research Program (HAARP) facility is presented in this work. These experiments have provided additional quantitative interpretation of the SEE spectrum produced by MSBS to yield diagnostic measurements of the electron temperature and ion composition in the heated ionosphere. SEE spectral emission lines corresponding to ion acoustic (IA) and electrostatic ion cyclotron (EIC) mode excitation were observed with a shift in frequency up to a few tens of Hz from the pump frequency for heating near the third harmonic of the electron gyrofrequency 3fce. The threshold of each emission line has been measured by changing the pump wave power. The excitation threshold of IA and EIC emission lines originating at the reflection and upper hybrid altitudes is measured for various beam angles relative to the magnetic field. Variation of strength of MSBS emission lines with pump frequency relative to 3fce and 4fce is also studied. A full wave solution has been used to estimate the amplitude of the electric field at the interaction altitude. The estimated instability threshold using the theoretical model is compared with the threshold of MSBS lines in the experiment and possible diagnostic information for the background ionospheric plasma is discussed. Simultaneous formation of artificial field‐aligned irregularities (FAIs) and suppression of the MSBS process is investigated. This technique can be used to estimate the growth time of artificial FAIs which may result in determination of plasma waves and physical process involved in the formation of FAIs.
Numerical derivation of dispersion coefficients for flow through three‐dimensional randomly packed beds of monodisperse spheres
Authors: Jourak Amir , Hellström J. Gunnar I. , Lundström T. Staffan , Frishfelds Vilnis
Published: November 2013

The longitudinal (DL) and transverse (DT) dispersion coefficients for flow through randomly packed beds of discrete monosized spherical particles are studied. The three‐dimensional (3‐D) porous‐medium model consists of thousands of spherical particles that are divided into cells using Voronoi diagrams. The relationship between the variation of the dual stream function and the vorticity between neighboring particles is derived using Laurent series. The whole flow pattern at low particle Reynolds number is then obtained by minimization of the dissipation rate of energy with respect to the dual stream function. The DLis obtained by fitting the resulting effluent curve to a 1‐D solution of a continuous model. The DTis obtained by fitting the numerical concentration profile to an approximate 2‐D solution. The derived DLand DTvalues are in agreement with 3‐D experimental data from the literature enabling a study of the effects of pore structure and porosity on DLand DT. © 2013 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical EngineersAIChE J60: 749–761, 2014
N‐Heterocyclic carbene/phosphite synergistically assisted Pd/C‐catalyzed Suzuki coupling of aryl chlorides
Authors: Ke Haihua , Chen Xiaofeng , Zou Gang
Published: November 2013

An N‐heterocyclic carbene and phosphite synergistically enhanced Pd/C catalyst system has been developed for Suzuki coupling of aryl chlorides and aryl boronic acids from commercially available Pd/C with sterically demanding N,N′‐bis(2,6‐diisopropylphenyl)imidazolylidene and trimethylphosphite. A remarkable increase in catalytic activity of Pd/C was observed when used along with 1 equiv. N,N′‐bis(2,6‐diisopropylphenyl)imidazolium chloride and 2 equiv. phosphite with respect to palladium in appropriate solvents that were found to play a crucial role in Pd/C‐NHC‐P(OR)3‐catalyzed Suzuki coupling. A dramatic ortho‐substitution effect of carbonyl and nitrile groups in aryl chlorides was observed and explained by a modified quasi‐heterogeneous catalysis mechanism. The Pd/C catalyst could be easily recovered from reaction mixtures by simple filtration and only low palladium contamination was detected in the biparyl products. A practical process for the synthesis of 4‐biphenylcarbonitrile has therefore been developed using the N‐heterocyclic carbene/phosphite‐assisted Pd/C‐catalyzed Suzuki coupling. Copyright © 2013 John Wiley & Sons, Ltd.
Architectural characteristics of stochastic honeycombs fabricated from varying melt strength polypropylenes
Authors: Hostetter Megan , Hibbard Glenn D.
Published: November 2013

Stochastic honeycombs are a cellular polymer fabricated through a simple melt‐stretching process. In this study, five polypropylenes (PP) with varying rheological properties were used to fabricate stochastic honeycombs over a range of densities. Rheology tests were performed to determine the melt behavior, while micro‐CT scans were used as a nondestructive characterization technique to determine the internal architecture. The sandwich structure consists of parallel skins separated by a network of interconnected webs. The cross‐sectional area decreased from unit area at the skins to a plateau over the middle third of the honeycomb height where the cross‐sectional area and total edge length of the webs were relatively constant. The rheological properties of the polymer were found to determine the web length per unit area, while the starting areal density of the polymer controlled the mid‐height cross‐sectional area. Other features, such as archways and buttresses, act as secondary structures that support the webs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40074.
A bibliometric study of highly cited reviews in the Science Citation Index expanded™
Authors: Ho Yuh‐Shan , Kahn Michael
Published: November 2013

Some 1,857 highly cited reviews, namely those cited at least 1,000 times since publication to 2011, were identified using the data hosted on the Science Citation Index Expanded™ database (Thomson Reuters, New York, NY) between 1899 and 2011. The data are disaggregated by publication date, citation counts, journals, Web of Science® (Thomson Reuters) subject areas, citation life cycles, and publications by Nobel Prize winners. Six indicators, total publications, independent publications, collaborative publications, first‐author publications, corresponding‐author publications, and single‐author publications were applied to evaluate publication of institutions and countries. Among the highly cited reviews, 33% were single‐author, 61% were single‐institution, and 83% were single‐country reviews. The United States ranked top for all 6 indicators. The G7 (United States, United Kingdom, Germany, Canada, France, Japan, and Italy) countries were the site of almost all the highly cited reviews. The top 12 most productive institutions were all located in the United States with Harvard University (Cambridge, MA) the leader. The top 3 most productive journals were Chemical Reviews, Nature, and the Annual Review of Biochemistry. In addition, the impact of the reviews was analyzed by total citations from publication to 2011, citations in 2011, and citation in publication year.
Measures for impact, consistency, and the h‐ and g‐indices
Authors: Prathap Gangan
Published: November 2013

An altogether different view on the properties of a good performance measure than that given in Egghe (2012) is offered. Egghe argued that a good impact measure should reward nonconsistency; that is, the more citations over papers are unequally distributed, the higher the impact should be. Here, a quantitative proxy for consistency is offered, and it is shown that as consistency increases, the ideal performance measure, which is sensitive to changes in consistency, should increase, reflecting this virtue.
The Synthesis of Magnetic Lysozyme‐Imprinted Polymers by Means of Distillation–Precipitation Polymerization for Selective Protein Enrichment
Authors: Cao Jiali , Zhang Xihao , He Xiwen , Chen Langxing , Zhang Yukui
Published: November 2013

A protein imprinting approach for the synthesis of core–shell structure nanoparticles with a magnetic core and molecularly imprinted polymer (MIP) shell was developed using a simple distillation–precipitation polymerization method. In this work, Fe3O4 magnetic nanoparticles were first synthesized through a solvothermal method and then were conveniently surface‐modified with 3‐(methacryloyloxy)propyltrimethoxylsilane as anchor molecules to donate vinyl groups. Next a high‐density MIP shell was coated onto the surface of the magnetic nanoparticles by the copolymerization of functional monomer acrylamide (AAm), cross‐linking agent N,N′‐methylenebisacrylamide (MBA), the initiator azodiisobutyronitrile (AIBN), and protein in acetonitrile heated at reflux. The morphology, adsorption, and recognition properties of the magnetic molecularly imprinted nanoparticles were investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and rebinding experiments. The resulting MIP showed a high adsorption capacity (104.8 mg g−1) and specific recognition (imprinting factor=7.6) to lysozyme (Lyz). The as‐prepared Fe3O4@Lyz‐MIP nanoparticles with a mean diameter of 320 nm were coated with an MIP shell that was 20 nm thick, which enabled Fe3O4@Lyz‐MIP to easily reach adsorption equilibrium. The high magnetization saturation (40.35 emu g−1) endows the materials with the convenience of magnetic separation under an external magnetic field and allows them to be subsequently reused. Furthermore, Fe3O4@Lyz‐MIP could selectively extract a target protein from real egg‐white samples under an external magnetic field.
Influence of magnetic fields on the hydration process of amino acids: Vibrational spectroscopy study of L‐phenylalanine and L‐glutamine
Authors: De Ninno Antonella , Castellano Agostina Congiu
Published: November 2013

Attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy has been used to investigate the effect of weak electromagnetic fields on the structure of L‐glutamine (L‐Gln) and L‐phenylalnine (L‐Phe) in aqueous solution. It has been found that the exposure to a DC field or a 50 Hz AC field, for a short time induces modifications in the spectra of exposed samples in agreement with our preceding observations on glutamic acid. Furthermore, the acid–base equilibrium has been investigated by using the ratio of the intensity of the deprotonated on protonated species. In the case of L‐Phe, the exposure induces a measurable shift of acid dissociation constant pKa1 out of the experimental errors, while in case of L‐Gln, the effect is under the limit detectable with this method. The phenomenon of the shift of the acid–base equilibrium has been connected elsewhere to modification of the water–water hydrogen bonds in the water around both the backbone and the residue (R). Here we suggest that the magnetic field modifies the water structure around the molecules and changes the hydrophobic interactions allowing the molecules of amino acids to aggregate. The differences observed in the behavior of L‐Phe and L‐Gln may be related to the differences in the polarity of their residues. Bioelectromagnetics. 35:129–135, 2014. © 2013 Wiley Periodicals, Inc.
Electric field‐induced effects on yeast cell wall permeabilization
Authors: Stirke Arunas , Zimkus Aurelijus , Ramanaviciene Almira , Balevicius Saulius , Zurauskiene Nerija , Saulis Gintautas , Chaustova Larisa , Stankevic Voitech , Ramanavicius Arunas
Published: November 2013

The permeability of the yeast cells (Saccharomyces cerevisiae) to lipophilic tetraphenylphosphonium cations (TPP+) after their treatment with single square‐shaped strong electric field pulses was analyzed. Pulsed electric fields (PEF) with durations from 5 to 150 µs and strengths from 0 to 10 kV/cm were applied to a standard electroporation cuvette filled with the appropriate buffer. The TPP+ absorption process was analyzed using an ion selective microelectrode (ISE) and the plasma membrane permeability was determined by measurements obtained using a calcein blue dye release assay. The viability of the yeast and the inactivation of the cells were determined using the optical absorbance method. The experimental data taken after yeasts were treated with PEF and incubated for 3 min showed an increased uptake of TPP+ by the yeast. This process can be controlled by setting the amplitude and pulse duration of the applied PEF. The kinetics of the TPP+ absorption process is described using the second order absolute rate equation. It was concluded that the changes of the charge on the yeast cell wall, which is the main barrier for TPP+, is due to the poration of the plasma membrane. The applicability of the TPP+ absorption measurements for the analysis of yeast cells electroporation process is also discussed. Bioelectromagnetics. 35:136–144, 2014. © 2013 Wiley Periodicals, Inc.
Assessment of extremely low frequency magnetic field exposure from GSM mobile phones
Authors: Calderón Carolina , Addison Darren , Mee Terry , Findlay Richard , Maslanyj Myron , Conil Emmanuelle , Kromhout Hans , Lee Ae‐kyoung , Sim Malcolm R. , Taki Masao , Varsier Nadège , Wiart Joe , Cardis Elisabeth
Published: November 2013

Although radio frequency (RF) electromagnetic fields emitted by mobile phones have received much attention, relatively little is known about the extremely low frequency (ELF) magnetic fields emitted by phones. This paper summarises ELF magnetic flux density measurements on global system for mobile communications (GSM) mobile phones, conducted as part of the MOBI‐KIDS epidemiological study. The main challenge is to identify a small number of generic phone models that can be used to classify the ELF exposure for the different phones reported in the study. Two‐dimensional magnetic flux density measurements were performed on 47 GSM mobile phones at a distance of 25 mm. Maximum resultant magnetic flux density values at 217 Hz had a geometric mean of 221 (+198/−104) nT. Taking into account harmonic data, measurements suggest that mobile phones could make a substantial contribution to ELF exposure in the general population. The maximum values and easily available variables were poorly correlated. However, three groups could be defined on the basis of field pattern indicating that manufacturers and shapes of mobile phones may be the important parameters linked to the spatial characteristics of the magnetic field, and the categorization of ELF magnetic field exposure for GSM phones in the MOBI‐KIDS study may be achievable on the basis of a small number of representative phones. Such categorization would result in a twofold exposure gradient between high and low exposure based on type of phone used, although there was overlap in the grouping. Bioelectromagnetics. 35:210–221, 2014. © 2013 Wiley Periodicals, Inc.
DNA Re‐EvolutioN: A game for learning molecular genetics and evolution
Authors: Miralles Laura , Moran Paloma , Dopico Eduardo , Garcia‐Vazquez Eva
Published: November 2013

Evolution is a main concept in biology, but not many students understand how it works. In this article we introduce the game DNA Re‐EvolutioN as an active learning tool that uses genetic concepts (DNA structure, transcription and translation, mutations, natural selection, etc.) as playing rules. Students will learn about molecular evolution while playing a game that mixes up theory and entertainment. The game can be easily adapted to different educational levels. The main goal of this play is to arrive at the end of the game with the longest protein. Students play with pawns and dices, a board containing hypothetical events (mutations, selection) that happen to molecules, “Evolution cards” with indications for DNA mutations, prototypes of a DNA and a mRNA chain with colored “nucleotides” (plasticine balls), and small pieces simulating t‐RNA with aminoacids that will serve to construct a “protein” based on the DNA chain. Students will understand how changes in DNA affect the final protein product and may be subjected to positive or negative selection, using a didactic tool funnier than classical theory lectures and easier than molecular laboratory experiments: a flexible and feasible game to learn and enjoy molecular evolution at no‐cost. The game was tested by majors and non‐majors in genetics from 13 different countries and evaluated with pre‐ and post‐tests obtaining very positive results. © 2013 by The International Union of Biochemistry and Molecular Biology, 41(6):396–401, 2013
Lanthanide Metal–Organic Frameworks Showing Luminescence in the Visible and Near‐Infrared Regions with Potential for Acetone Sensing
Authors: Dang Song , Min Xue , Yang Weiting , Yi Fei‐Yan , You Hongpeng , Sun Zhong‐Ming
Published: November 2013

The luminescent properties of a family of lanthanide metal–organic frameworks LnL (Ln=Y, La–Yb, except Pm; L=4,4′‐({2‐[(4‐carboxyphenoxy)methyl]‐2‐methylpropane‐1,3‐diyl}bis{oxy})dibenzoic acid) have been explored, and the energy‐transfer process in the compounds has been carefully analyzed. The visible‐emitting Tb0.08Gd0.92L and the near‐infrared (NIR)‐luminescent Yb0.10Gd0.90L show excellent optical performances and can be considered as fluorescent probes for acetone sensing based on luminescence quenching effects arising from host–guest interactions. Moreover, GdL exhibits a strong second harmonic generation (SHG) signal 6.1 times that of potassium dihydrogen phosphate (KDP) and an outstanding phase‐matchable effect. These lanthanide compounds combining fluorescent and nonlinear optical (NLO) properties could meet further requirements as multifunctional materials.
Structural Diversity of Copper(I)–N‐Heterocyclic Carbene Complexes; Ligand Tuning Facilitates Isolation of the First Structurally Characterised Copper(I)–NHC Containing a Copper(I)–Alkene Interaction
Authors: Lake Benjamin R. M. , Willans Charlotte E.
Published: November 2013

The preparation of a series of imidazolium salts bearing N‐allyl substituents, and a range of substituents on the second nitrogen atom that have varying electronic and steric properties, is reported. The ligands have been coordinated to a copper(I) centre and the resulting copper(I)–NHC (NHC=N‐heterocyclic carbene) complexes have been thoroughly examined, both in solution and in the solid‐state. The solid‐state structures are highly diverse and exhibit a range of unusual geometries and cuprophilic interactions. The first structurally characterised copper(I)–NHC complex containing a copper(I)–alkene interaction is reported. An N‐pyridyl substituent, which forms a dative bond with the copper(I) centre, stabilises an interaction between the metal centre and the allyl substituent of a neighbouring ligand, to form a 1D coordination polymer. The stabilisation is attributed to the pyridyl substituent increasing the electron density at the copper(I) centre, and thus enhancing the metal(d)‐to‐alkene(π*) back‐bonding. In addition, components other than charge transfer appear to have a role in copper(I)–alkene stabilisation because further increases in the Lewis basicity of the ligand disfavours copper(I)–alkene binding.
The Ambivalent Chemistry of a Free Anionic N‐Heterocyclic Carbene Decorated with a Malonate Backbone: The Plus of a Negative Charge
Authors: César Vincent , Labat Stéphane , Miqueu Karinne , Sotiropoulos Jean‐Marc , Brousses Rémy , Lugan Noël , Lavigne Guy
Published: November 2013

The anionic heterocycle “[maloNHC]−”, ([1]−), is the archetype of a growing family of N‐heterocyclic carbenes incorporating an anionic backbone; here, a malonate group. A comprehensive experimental exploration of its chemistry as a free entity (in the form of its lithium salt [1]⋅Li) is presented, and rationalized using DFT calculations at the B3LYP/6‐31+G** level of theory. For the sake of comparison, similar computations were performed on other representative carbene types. Reactions of [1]⋅Li with a broad series of electrophilic reagents were used to ascertain its intrinsic nature as a nucleophilic carbene. Unexpectedly, [1]⋅Li was also seen to react with the nucleophilic tert‐butylisocyanide, to give an anionic ketenimine, which could be subsequently derivatized, either into an imine by protonation of the ketenimine moiety, or into a neutral ketenimine by alkylation of the intracyclic malonate moiety. Further experiments on the electrophilic behavior of [1]⋅Li revealed its unexpected reactivity toward p‐chlorobenzaldehyde, resulting in a formal CH activation and the first structurally characterized keto‐tautomer of the Breslow intermediate. Finally, [1]⋅Li remarkably activates polar EH bonds, including NH bonds from ammonia and amines, SiH bonds, and BH bonds. Importantly, DFT calculations indicate the importance of counterion effects. In particular, the key to the observed reactivity appears to be a modulation of energy levels associated with a dynamic variability of the LiO distance between the remote malonate group and the counterion.
Pharmacokinetics and safety of teneligliptin in subjects with hepatic impairment
Authors: Halabi Atef , Maatouk Haidar , Siegler Karl Ernst , Faisst Nadja , Hinrichsen Holger
Published: November 2013

The pharmacokinetics of teneligliptin was compared in 3 groups of 8 subjects assigned according to their degree of hepatic impairment (mild, moderate, or matched healthy subjects). Hepatic impairment was associated with an increase in maximal plasma concentration (Cmax) and overall exposure (AUC0–∞) to teneligliptin. Geometric least square mean ratios for Cmax in subjects with mild and moderate hepatic impairment were 25% and 38% higher than in healthy subjects, and those for AUC0–∞ were 46% and 59% higher than in healthy subjects, respectively. For both parameters, the upper limit of the 90% confidence intervals was outside the 80%–125% “no effect” limit, but below the FDA‐recommended “dose‐adjustment” boundary of 200%. The lower mean total clearance in subjects with mild (9.79 L/h) or moderate (8.57 L/h) hepatic impairment resulted in longer mean half‐lives (27.9 and 30.9 hours, respectively) than in healthy subjects (clearance: 13.11 L/h, half life: 24.8 hours). Protein binding ranged between 36.9% and 47.5% in subjects with hepatic impairment and between 32.5% and 34.5% in healthy subjects. Overall, teneligliptin was well tolerated by subjects with hepatic impairment. These results may indicate that caution will be needed when administering teneligliptin to subjects with hepatic impairment.