bluuebunny/crossref_metadata_2025 huggingface dataset:
Scheduling algorithms‐by‐blocks on small clusters
Authors: Igual Francisco D. , Quintana‐Ortí Gregorio , van de Geijn Robert
Published: March 2012

The arrival of multicore architectures has generated an interest in reformulating dense matrix computations as algorithms‐by‐blocks, where submatrices are units of data and computations with those blocks are units of computation. Rather than directly executing such an algorithm, a directed acyclic graph is generated at runtime that is then scheduled by a runtime system such as SuperMatrix. The benefit is a clear separation of concerns between the library and the heuristics for scheduling. In this paper, we show that this approach can be taken one step further using the same methodology and an ad hoc runtime to map algorithms‐by‐blocks to small clusters. With no change to the library code, and the application that uses it, the computational power of such small clusters can be utilized. An impressive performance on a number of small clusters is reported. As a proof of the flexibility of the solution, we report performance results on accelerated clusters based on graphics processors. We believe this to be a possible step towards programming many‐core architectures, as demonstrated by a port of the solution to Intel's Single‐chip Cloud Computer (Intel, Santa Clara, CA, USA). Copyright © 2012 John Wiley & Sons, Ltd.
Field‐based insights to the evolution of specialization: plasticity and fitness across habitats in a specialist/generalist species pair
Authors: Griffith Timothy , Sultan Sonia E.
Published: March 2012

Factors promoting the evolution of specialists versus generalists have been little studied in ecological context. In a large‐scale comparative field experiment, we studied genotypes from naturally evolved populations of a closely related generalist/specialist species pair (Polygonum persicariaandP. hydropiper), reciprocally transplanting replicates of multiple lines into open and partially shaded sites where the species naturally co‐occur. We measured relative fitness, individual plasticity, herbivory, and genetic variance expressed in the contrasting light habitats at both low and high densities. Fitness data confirmed that the putative specialist out‐performed the generalist in only one environment, the favorable full sun/low‐density environment to which it is largely restricted in nature, while the generalist had higher lifetime reproduction in both canopy and dense neighbor shade. The generalist,P. persicaria, also expressed greater adaptive plasticity for biomass allocation and leaf size in shaded conditions than the specialist. We found no evidence that the ecological specialization ofP. hydropiperreflects either genetically based fitness trade‐offs or maintenance costs of plasticity, two types of genetic constraint often invoked to prevent the evolution of broadly adaptive genotypes. However, the patterns of fitness variance and herbivore damage revealed how release from herbivory in a new range can cause an introduced species to evolve as a specialist in that range, a surprising finding with important implications for invasion biology. Patterns of fitness variance between and within sites are also consistent with a possible role for the process of mutation accumulation (in this case, mutations affecting shade‐expressed phenotypes) in the evolution and/or maintenance of specialization inP. hydropiper.
The genetics of phenotypic plasticity. X. Variation versus uncertainty
Authors: Scheiner Samuel M. , Holt Robert D.
Published: March 2012

Despite the apparent advantages of adaptive plasticity, it is not common. We examined the effects of variation and uncertainty on selection for plasticity using an individual‐based computer simulation model. In the model, the environment consisted of a linear gradient of 50 demes with dispersal occurring either before or after selection. Individuals consisted of multiple loci whose phenotypic expression either are affected (plastic) or are not affected (nonplastic) by the environment. Typically, evolution occurred first as genetic differentiation, which was then replaced by the evolution of adaptive plasticity, opposite to the evolutionary trend that is often assumed. Increasing dispersal rates selected for plasticity, if selection occurred before dispersal. If selection occurred after dispersal, the highest plasticity was at intermediate dispersal rates. Temporal variation in the environment occurring after development, but before selection, favored the evolution of plasticity. With dispersal before selection, such temporal variation resulted in hyperplasticity, with a reaction norm much steeper than the optimum. This effect was enhanced with negative temporal autocorrelation and can be interpreted as representing a form of bet hedging. As the number of nonplastic loci increased, plasticity was disfavored due to an increase in the uncertainty of the genomic environment. This effect was reversed with temporal variation. Thus, variation and uncertainty affect whether or not plasticity is favored with different sources of variation—arising from the amount and timing of dispersal, from temporal variation, and even from the genetic architecture underlying the phenotype—having contrasting, interacting, and at times unexpected effects.
Seasonal dynamics of arboreal spider diversity in a temperate forest
Authors: Hsieh Yu‐Lung , Linsenmair Karl Eduard
Published: March 2012

Measuring and estimating biodiversity patterns is a fundamental task of the scientist working to support conservation and inform management decisions. Most biodiversity studies in temperate regions were often carried out over a very short period of time (e.g., a single season) and it is often—at least tacitly—assumed that these short‐term findings are representative of long‐term general patterns. However, should the studied biodiversity pattern in fact contain significant temporal dynamics, perhaps leading to contradictory conclusions. Here, we studied the seasonal diversity dynamics of arboreal spider communities dwelling in 216 European beeches (Fagus sylvatica L.) to assess the spider community composition in the following seasons: two cold seasons (I: November 2005–January 2006; II: February–April) and two warm seasons (III: May–July; IV: August–October). We show that the usually measured diversity of the warm season community (IV: 58 estimated species) alone did not deliver a reliable image of the overall diversity present in these trees, and therefore, we recommend it should not be used for sampling protocols aimed at providing a full picture of a forest's biodiversity in the temperate zones. In particular, when the additional samplings of other seasons (I, II, III) were included, the estimated species richness nearly doubled (108). Community I possessed the lowest diversity and evenness due to the harsh winter conditions: this community was comprised of one dominant species together with several species low in abundance. Similarity was lowest (38.6%) between seasonal communities I and III, indicating a significant species turnover due to recolonization, so that community III had the highest diversity. Finally, using nonparametric estimators, we found that further sampling in late winter (February–April) is most needed to complete our inventory. Our study clearly demonstrates that seasonal dynamics of communities should be taken into account when studying biodiversity patterns of spiders, and probably forest arthropods in general.
Synthesis, Characterization, and in vitro Testing of a Bacteria‐Targeted MR Contrast Agent
Authors: Matosziuk Lauren M. , Harney Allison S. , MacRenaris Keith W. , Meade Thomas J.
Published: March 2012

A bacteria‐targeted MR contrast agent, Zn‐1, consisting of two Zn‐dipicolylamine (Zn‐dpa) groups conjugated to a GdIII chelate has been synthesized and characterized. In vitro studies with S. aureus and E. coli show that Zn‐1 exhibits a significant improvement in bacteria labeling efficiency vs. control. Studies with a structural analogue, Zn‐2, indicate that removal of one Zn‐dpa moiety dramatically reduces the agent's affinity for bacteria. The ability of Zn‐1 to significantly reduce the T1 of labeled vs. unlabeled bacteria, resulting in enhanced MR image contrast, demonstrates its potential for visualizing bacterial infections in vivo.
Syntheses, Characterization, and Properties of Functionalized 9,10‐Bis(1,3‐dithiol‐2‐ylidene)‐9,10‐dihydroanthracene Derivatives and Tricarbonylrhenium(I) Complexes
Authors: Hu Liang , Qin Jie , Zhu Rong‐Mei , Li Yi‐Zhi , Zuo Jing‐Lin , You Xiao‐Zeng
Published: March 2012

New π‐extended tetrathiafulvalenes (exTTF) 4a, 4b, 5a, and 5b have been synthesized by direct phosphite‐mediated cross‐couplings of anthraquinone with 1,3‐dithiole‐2‐thione derivatives. Further coordination reactions of the exTTF ligands including the phenanthroline unit (5a and 5b) with [Re(CO)5Cl] afford interesting tricarbonylrhenium(I) complexes 6a and 6b, respectively. The X‐ray crystal structures of compounds 4a and 4b show a saddlelike conformation of the exTTF framework. The electrochemical and spectroscopic properties of compounds 4a–6a and 4b–6b have been studied. The results suggest that the oxidation of the exTTF derivatives shows the typical quasi‐reversible two‐electron oxidation wave of the exTTF core at potentials that vary depending on the substituents.
Synthesis of Calixarene‐Based Bis(iminophosphoranes) and Their Use in Suzuki–Miyaura Cross‐Coupling
Authors: Monnereau Laure , Sémeril David , Matt Dominique
Published: March 2012

Calix[4]arene‐derived bis(iminophosphoranes) have been synthesised and assessed in palladium‐catalysed cross‐couplings between phenylboronic acid and aryl bromides orchlorides. TOFs of up to 35100 mol(ArPh formed) mol(Pd)–1 h–1were observed in the reaction with 4‐bromoanisole. The ligands showed higher activities than the parent calixarene–diphosphanes. Their relatively good performances possibly arise from their ability to generate chelated intermediates in highly crowded metal environments, which incidentally facilitates the reductive elimination step.
HgII‐Selective Fluorescent Indicator: One‐Step Synthesis
Authors: Kim Seul‐Bi , Cho Dong‐Gyu
Published: March 2012

Fluorescent indicator 2 was synthesized by a single‐step reaction. The indicator underwent an HgII‐selective reaction (hydrolysis/decarboxylation sequence) in the presence of HgII, which was verified by using LC‐MS and NMR techniques.
Optimized earthquake response of multi‐storey buildings with seismic isolation at various elevations
Authors: Charmpis Dimos C. , Komodromos Petros , Phocas Marios C.
Published: March 2012

The response of multi‐storey structures can be controlled under earthquake actions by installing seismic isolators at various storey levels. By vertically distributing isolation devices at various elevations, the designer is provided with numerous options to appropriately adjust the seismic performance of a building. However, introducing seismic isolators at various storey levels is not a straightforward task, as it may lead to favourable or unfavourable structural behaviour depending on a large number of factors. As a consequence, a rather chaotic decision space of seismic isolation configurations arises, within which a favourable solution needs to be located. The search for favourable isolators' configurations is formulated in this work as a single‐objective optimization task. The aim of the optimization process is to minimize the maximum floor acceleration of the building under consideration, while constraints are specified to control the maximum interstorey drift, the maximum base displacement and the total seismic isolation cost. A genetic algorithm is implemented to perform this optimization task, which selectively introduces seismic isolators at various elevations, in order to identify the optimal configuration for the isolators satisfying the pre‐specified constraints. This way, optimized earthquake response of multi‐storey buildings can be obtained. The effectiveness of the proposed optimization procedure in the design of a seismically isolated structure is demonstrated in a numerical study using time‐history analyses of a typical six‐storey building. Copyright © 2012 John Wiley & Sons, Ltd.
Analytical computation of the correlation of spreading sequences for nonlinear OQPSK‐type modulations
Authors: Afonso Daniel , Cercas Francisco , Dinis Rui , Rodrigues Rui , Luz Ângelo
Published: March 2012

In this paper we study the behavior and correlation properties of some spreading sequences when applied to a system using nonlinear offset quadrature phase‐shift keying‐type modulations. These signals, which include as special cases continuous‐phase modulation schemes, can be designed to have very low envelope fluctuations or even a constant envelope, making them compatible with a very low‐cost and power‐efficient grossly nonlinear amplification. We use an analytical method to derive the correlation of those signals. The resulting expressions are then applied to maximum‐length sequences, Kasami, and Tomlinson, Cercas, Hughes sequences. It is shown that Tomlinson, Cercas, Hughes sequences have better correlation properties than other spreading sequences. Copyright © 2012 John Wiley & Sons, Ltd.
Real‐Time Forecasts of Inflation: The Role of Financial Variables
Authors: Monteforte Libero , Moretti Gianluca
Published: March 2012

We present a mixed‐frequency model for daily forecasts of euro area inflation. The model combines a monthly index of core inflation with daily data from financial markets; estimates are carried out with the MIDAS regression approach. The forecasting ability of the model in real time is compared with that of standard VARs and of daily quotes of economic derivatives on euro area inflation. We find that the inclusion of daily variables helps to reduce forecast errors with respect to models that consider only monthly variables. The mixed‐frequency model also displays superior predictive performance with respect to forecasts solely based on economic derivatives. Copyright © 2012 John Wiley & Sons, Ltd.
Accurate Imputation of Rare and Common Variants in a Founder Population From a Small Number of Sequenced Individuals
Authors: Uricchio Lawrence H. , Chong Jessica X. , Ross Kevin D. , Ober Carole , Nicolae Dan L.
Published: March 2012

Advances in DNA sequencing technologies have greatly facilitated the discovery of rare genetic variants in the human genome, many of which may contribute to common disease risk. However, evaluating their individual or even collective effects on disease risk requires very large sample sizes, which involves study designs that are often prohibitively expensive. We present an alternative approach for determining genotypes in large numbers of individuals for all variants discovered in the sequence of relatively few individuals. Specifically, we developed a new imputation algorithm that utilizes whole‐exome sequencing data from 25 members of the South Dakota Hutterite population, and genome‐wide single nucleotide polymorphism (SNP) genotypes from >1,400 individuals from the same founder population. The algorithm relies on identity‐by‐descent sharing of phased haplotypes, a different strategy than the linkage disequilibrium methods found in most imputation algorithms. We imputed genotypes discovered in the sequence data to on average ∼77% of chromosomes among the 1,400 individuals. Median R2 between imputed and directly genotyped data was >0.99. As expected, many variants that are vanishingly rare in European populations have risen to larger frequencies in the founder population and would be amenable to single‐SNP analyses. Genet. Epidemiol. 36:312–319, 2012. © 2012 Wiley Periodicals, Inc.
Training older workers: Lessons learned, unlearned, and relearned from the field of instructional design
Authors: Williams van Rooij Shahron
Published: March 2012

Changing workforce demographics have highlighted the need to provide training and development opportunities for older workers. This article critically examines the current state of research on the use of systematic instructional design procedures to develop work‐related training that is inclusive of older workers. The review reveals a disconnect between what the literature recommends to achieve age‐inclusive design and what is offered as evidence of age‐inclusive design. Age‐related generalizations about cognition and learning capacity often serve as the basis for design decisions, with little attention paid to the role of training context and content. The article recommends that this disconnect be resolved and offers some specific suggestions about how human resource managers can integrate sound instructional design principles into the training and development component of their talent management strategies. © 2012 Wiley Periodicals, Inc.
Do conflict management systems matter?
Authors: Roche William , Teague Paul
Published: March 2012

The most influential current idea in the theory of conflict management concerns the design features and supposed superior outcomes of conflict management systems combining interest‐based and rights‐based practices for resolving conflict in organizations. Yet much of the literature in the area is highly prescriptive and draws heavily either on exemplary case studies or descriptive data. Using focus groups of HR practitioners and experts in conflict resolution to develop a questionnaire covering the main conflict management practices associated with the theory of conflict management systems, the study analyzes data from a survey of firms in the Republic of Ireland to examine quantitatively the effects of conflict management systems on organizational outcomes. While proactive line management and supervisory engagement in conflict resolution as a key dimension of conflict management systems is found to be positively associated with a range of organizational outcomes, no evidence is found for the kind of system effects proposed in the theoretical and prescriptive literature. © 2012 Wiley Periodicals, Inc.
Randomised health services studies
Authors: Hakama Matti , Malila Nea , Dillner Joakim
Published: March 2012

The randomised controlled (or clinical) trial (RCT) is recognized as the most valid among the study designs. The use of RCT in research is widespread and well formalised. In contrast, implementations of new methods and policies in routine health care are commonly lacking a formalised design, impairing the ability to evaluate and improve health care. Use of experimental designs in health care is possible at the implementation phase of clinical or preventive action or more broad process‐of‐care. We propose the terminology randomised health services studies (RHS) to denote the use of a randomised design with observations in routine health care, regardless of whether randomisation is done at individual, population or process level. In contrast to RCT, the RHS should be based on the same regulative actions, funding mechanisms and ethical framework as routine health care itself. This commentary discusses the different basis, practicalities, and formalities that distinguish the RHS from the RCT. Development of a formalised framework for RHS, including distinct registration, could contribute to an increased use of valid methods in effectiveness research, thus gaining better and more direct evidence on routine medical practice.
IMPLIED VOLATILITY AND THE RISK‐RETURN RELATION: A NOTE
Authors: Kanas Angelos
Published: March 2012

A strong and positive risk‐return relation for the S&P 500 market index is uncovered when the implied volatility index is allowed for in the conditional variance equation. This result holds for five alternative Generalised Autoregressive Heteroscedasticity (GARCH) specifications and irrespective of the conditional distribution. Monte Carlo evidence suggests that if implied volatility is not included while it should be, then the risk‐return relation is more likely to be negative or weak. Copyright © 2012 John Wiley & Sons, Ltd.
Characterization of oral squamous cell carcinoma based on higher‐harmonic generation microscopy
Authors: Tsai Ming‐Rung , Shieh Dar‐Bin , Lou Pei‐Jen , Lin Chih‐Feng , Sun Chi‐Kuang
Published: March 2012

In vivo higher‐harmonic generation microscopy (HGM) performed on healthy human oral mucosa not only provides images with a <500 nm lateral resolution at a 280 μm penetration depth, but also leaves no photodamages in the tissues. These advantages suggest that HGM could serve as an ideal virtual biopsy tool for in vivo, in situ, and immediate histopathological diagnosis of oral cancer. However, translation of such mechanism for clinical cancer diagnosis requires evidence based algorithm capable to differentiate cancerous tissues from normal. It is thus critical to investigate if the endogenous contrast provided by the HGM would be high enough to differentiate cancerous versus normal tissues in human oral mucosa. In this report, ex vivo HGM study was performed on the cancerous mucosa from 10 patients with oral squamous cell carcinoma. Compared with histology, HGM revealed histopathological features including the cytological abnormalities, loss of differentiation, interruption of basement membrane, and irregular epithelial stratification in all 10 specimens. In addition, distinct patterns of collagen fibers and increased distribution area of actin filaments in tumor cells were noted. These results indicate HGM holds great potential for the optical biopsy screening of oral cancer lesions. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Whispering gallery mode aptasensors for detection of blood proteins
Authors: Pasquardini Laura , Berneschi Simone , Barucci Andrea , Cosi Franco , Dallapiccola Ramona , Insinna Massimiliano , Lunelli Lorenzo , Conti Gualtiero Nunzi , Pederzolli Cecilia , Salvadori Simone , Soria Silvia
Published: March 2012

Whispering gallery mode resonators (WGMR), as silica microspheres, have been recently proposed as an efficient tool for the realisation of optical biosensors. In this work we present a functionalization procedure based on the DNA‐aptamer sequence immobilization on WGMR, able to recognize specifically thrombin or VEGF protein, preserving a high Q factor. The protein binding was optically characterized in terms of specificity in buffer solution or in 10% diluted human serum. Simulation of the protein flow was found in good agreement with experimental data. The aptasensor was also chemically regenerated and tested again, demonstrating the reusability of our system. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of ultraviolet B radiation on physicochemical properties of human hair shaft
Authors: Kim Kyung Sook , Shin Min Kyung , Park Hun‐Kuk
Published: March 2012

Changes in physicochemical properties of the human hair shaft induced by UVB during the summer climate were investigated. Using atomic force microscopy and thermogravimetric analyzer measurements, we investigated the changes in hair shaft physical properties including morphology, roughness, and water content. The changes in chemical properties were investigated by using FTIR spectroscopy. Hair samples from 20 females without any chemical or physical stresses were investigated. The samples were exposed to various UVB doses of 400, 2,000, and 4,000 mJ/cm2, which correspond to the radiation times of 0.44, 2.22, and 4.44 h, respectively. The morphology and surface of the hair shaft was not significantly affected by UVB irradiation. The components of keratin were affected by the UVB irradiation where the amide A bands at 3,263 and 3,246 cm−1 of the proximal and distal roots, respectively, were shifted to higher band region because α‐helix converted to β‐sheet, and the stretching modes of CH lipid alkyl chains at 2,965 and 2,850 cm−1 in the proximal and distal roots, respectively, were developed. As the UVB intensity increased, the water content of the proximal root decreased. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.
High‐resolution subunit detection of glutamate receptor by ultrasmall gold nanoparticles
Authors: Loukanov Alexandre R. , Gagov Hristo
Published: March 2012

In this study, we aimed to increase the sensitivity of protein labeling using 1.4 nm gold nanoparticles and glutamate δ2 receptor (GluD2) from the postsynaptic membrane of the Purkinje cells. The very small marker size of the particles reduces the steric hindrance between antibodies leading to a higher labeling efficiency of more than one subunit per single receptor molecule. The nanoparticles are visible in 200 kV dark‐field scanning transmission electron microscope on freeze‐fractured carbon replica of nervous tissue after plasma cleaning treatment. The different elemental composition of nanoparticles as Au nanogold or CdS quantum dot can be distinguished by energy dispersive X‐ray spectroscopy. This method ensures detection of an average of three subunits per GluD2 and often labels all four of them with 1.4 nm Au nanoparticles. It is concluded that this high‐resolution microscopic method is useful for exploring the quaternary structure of membrane proteins. Microsc. Res. Tech. 75:1159–1164, 2012. © 2012 Wiley Periodicals, Inc.
Synthesis of 14C‐acanthoic acid
Authors: Rhee Sung‐Whi , Malerich Jeremiah P. , Lee Jung‐Joon , Tanga Mary J.
Published: March 2012

14C‐Acanthoic acid was prepared in four steps by a degradation/reconstitution strategy.
Identification and characterization of new Fusarium masked mycotoxins, T2 and HT2 glycosyl derivatives, in naturally contaminated wheat and oats by liquid chromatography–high‐resolution mass spectrometry
Authors: Lattanzio Veronica M.T. , Visconti Angelo , Haidukowski Miriam , Pascale Michelangelo
Published: March 2012

The presence of glucoside derivatives of T‐2 and HT‐2 toxins (type A trichothecene mycotoxins) in naturally contaminated wheat and oats is reported for the first time. The use of advanced high‐resolution mass spectrometry based on Orbitrap technology allowed to obtain molecular structure details by measuring exact masses of main characteristic fragments, with mass accuracy lower than 2.8 ppm (absolute value). A monoglucoside derivative of T‐2 toxin and two monoglucoside derivatives of HT‐2 toxin were identified and characterized. The analysis of their fragmentation patterns provided evidence for glucosylation at C‐3 position for T‐2 toxin and at C‐3 or C‐4 position for HT‐2 toxin.

A screening for the presence of these new masked forms of mycotoxins was carried out on a set of naturally contaminated wheat and oats samples. On the basis of peak area ratio between glucoside derivatives and free T‐2 and HT‐2 toxins, the presence of glucoside derivatives was more likely in wheat than in oats samples. The present work confirms the widespread occurrence of trichothecene glucosides in cereal grains naturally contaminated with the relevant unconjugated toxins, thus suggesting the importance of developing suitable analytical methods for their detection. Besides toxicity studies, tracking down these new masked forms of trichothecenes along the food/feed chain would enable to collect information on their relevance in human/animal exposure to mycotoxin risk. Copyright © 2012 John Wiley & Sons, Ltd.
Holocene pollen assemblages from coastal wetlands: differentiating natural and anthropogenic causes of change in the Thames estuary, UK
Authors: Waller Martyn , Grant Michael J.
Published: March 2012

Simultaneous changes in the representation of wetland and dry land taxa are a common feature of mid and late Holocene pollen diagrams from the coastal wetlands of North‐West Europe. Distinguishing both the areas affected and between natural and anthropogenic causes can be problematic. High temporal resolution, improved taxonomic procedures and multivariate statistics have been applied to two Thames estuary sites, along with simulation models, to resolve these issues. Large Poaceae pollen grains appear to be derived from wild grasses rather than cereals, while modelling indicates that even extensive clearance in dry land areas produces relatively minor changes in pollen assemblages where fen carr is the in situ vegetation. It is concluded that rapid/abrupt simultaneous pollen stratigraphic events in coastal wetlands are likely to have been caused by wetland vegetation changes alone. Simultaneous events, dating from c. 2150–1300 cal a BC, can be distinguished at 12 Thames estuary pollen sites. During this interval inter‐tidal environments expanded creating areas attractive to human populations for pasturage. This exploitation is likely to have led to further changes in wetland vegetation and increased clearance activity on adjacent dry land areas. In such circumstances disentangling the processes causing vegetation change is challenging, although considerably aided by the techniques adopted in this paper. Copyright © 2012 John Wiley & Sons, Ltd.
Integration of Analytic Hierarchy Process with Regression Analysis to Identify Attractive Locations for Market Expansion
Authors: Priya Preeti , Venkatesh Anand
Published: March 2012

Selection of new geographies in which to expand is a key decision for businesses aspiring to go beyond the opportunities in the existing markets. The conventional approaches of market selection can only provide a set of systematic steps for problem solving without considering the relationships between the decision factors. Decision models based on statistical techniques are able to examine the relationship between decision factors but are unable to effectively assist decision makers in identifying the most promising market, particularly in terms of prioritizing across decision factors. Analytic Hierarchy Process (AHP) is a commonly used approach for choosing alternatives by prioritizing across multiple decision factors. The typical AHP modelling requires knowledge of criteria and/or alternatives along with their relative weights, generally elicited from field experts. Quite often, firms encounter situations where decision makers are aware of only the overall objective and a set of earmarked geographies for setting up market locations while being relatively unaware of decision criteria and relative weights. This precludes using AHP to identify promising market locations. This paper conceptualizes a market selection decision model that integrates AHP with statistical modelling techniques to identify the attractive market locations for the purpose of expansion. The model first uses principal component analysis and multiple regression to determine significant decision criteria and their weights. Thereafter, it applies AHP to prioritize the market locations across the decision criteria. This integrative approach is illustrated for identifying the attractive locations in rural markets for a steel firm in India. The major advantage of this approach is that unlike the existing models, it works in situations when firms have not enough knowledge about factors for evaluating alternative market locations. Another key advantage of the proposed model is that of economizing resources for data collection on variables representing decision factors. Copyright © 2012 John Wiley & Sons, Ltd.
Diffusion kurtosis imaging and log‐normal distribution function imaging enhance the visualisation of lesions in animal stroke models
Authors: Grinberg Farida , Ciobanu Luisa , Farrher Ezequiel , Shah N. Jon
Published: March 2012

In this work, we report a case study of a stroke model in animals using two methods of quantification of the deviations from Gaussian behaviour: diffusion kurtosis imaging (DKI) and log‐normal distribution function imaging (LNDFI). The affected regions were predominantly in grey rather than in white matter. The parameter maps were constructed for metrics quantifying the apparent diffusivity (evaluated from conventional diffusion tensor imaging, DKI and LNDFI) and for those quantifying the degree of deviations (mean kurtosis and a parameter σ characterising the width of the distribution). We showed that both DKI and LNDFI were able to dramatically enhance the visualisation of ischaemic lesions in comparison with conventional methods. The largest relative change in the affected versus healthy regions was observed in the mean kurtosis values. The average changes in the mean kurtosis and σ values in the lesions were a factor of two to three larger than the relative changes observed in the mean diffusivity. In conclusion, the applied methods promise valuable perspectives in the assessment of stroke. Copyright © 2012 John Wiley & Sons, Ltd.
Localization and scheduling protocols for actor‐centric sensor networks
Authors: Das Sajal K. , Ghidini Giacomo , Navarra Alfredo , Pinotti Cristina M.
Published: March 2012

We propose novel localization and routing protocols in an actor‐centric wireless sensor network consisting of an actor node and a large number of energy‐constrained sensors operating under L different periodic sleep–awake schedules. Specifically, we propose a semidistributed localization algorithm in which a small subset of sensors extracts their positions in polar coordinates based on the messages received from the actor, and subsequently localizes (also in polar coordinates) the remaining sensors. By modeling the deployed sensors as a two‐dimensional Poisson point process and applying well‐known results from the coupon collector's problem and Chernoff bounds, we analytically derive and also validate, by simulation, the sensor density required to localize all sensors in the network with high probability. The actor‐centric network can be modeled by a cluster adjacency graph G with the help of the already localized polar coordinates that logically partition the network into concentric coronas (around the actor), each subdivided in a varying number of clusters (of almost the same area). To avoid intercluster collisions in G, sensors in different clusters transmit on different channels. A lower bound on the number of channels required to schedule the transmissions without collisions is obtained by solving a distance‐2 vertex coloring problem on G. Optimal and quasioptimal fully distributed algorithms are provided to determine the channel assigned to each cluster in constant time. Finally, we apply these results to develop a geographic routing protocol: the messages generated from the sensors in a given cluster are routed toward the actor through the unique shortest path of G that starts from the node associated with the cluster and goes up to the corona where the actor resides. In each cluster, to avoid redundant retransmissions toward the actor, we select L leaders, one for each periodic sleep–awake schedule. © Wiley Periodicals, Inc. NETWORKS, Vol. 2012.
Modulus‐based synchronous multisplitting iteration methods for linear complementarity problems
Authors: Bai Zhong‐Zhi , Zhang Li‐Li
Published: March 2012

By an equivalent reformulation of the linear complementarity problem into a system of fixed‐point equations, we construct modulus‐based synchronous multisplitting iteration methods based on multiple splittings of the system matrix. These iteration methods are suitable to high‐speed parallel multiprocessor systems and include the multisplitting relaxation methods such as Jacobi, Gauss–Seidel, successive overrelaxation, and accelerated overrelaxation of the modulus type as special cases. We establish the convergence theory of these modulus‐based synchronous multisplitting iteration methods and their relaxed variants when the system matrix is an H + ‐matrix. Numerical results show that these new iteration methods can achieve high parallel computational efficiency in actual implementations. Copyright © 2012 John Wiley & Sons, Ltd.
Robust C0 high‐order plate finite element for thin to very thick structures: mechanical and thermo‐mechanical analysis
Authors: Polit O. , Vidal P. , D'Ottavio M.
Published: March 2012

This paper presents a new C0 eight‐node quadrilateral finite element (FE) for geometrically linear elastic plates. This finite element aims at modeling both thin and thick plates without any pathologies of the classical plate finite elements (shear and Poisson or thickness locking, spurious modes, etc). A C1 FE was previously developed by the first author based on the kinematics proposed by Touratier. This new FE can be viewed as an evolution towards three directions: (1) use of only C0 FE approximations; (2) modeling of thick to thin structures; and (3) capability in multifield problems. The transverse normal stress is included allowing use of the three‐dimensional constitutive law. The element performances are evaluated on some standard plate tests, and comparisons are given with exact three‐dimensional solutions for plates under mechanical and thermal loads. Comparisons are made with other plate models using C1 and semi‐C1 FE approximations as well as with an eight node C0 FE based on the Reissner–Mindlin model. All results indicate that the present element is highly insensitive to mesh distortion, has very fast convergence properties and gives accurate results for displacements and stresses. Copyright © 2012 John Wiley & Sons, Ltd.
Response of imidazolinone‐tolerant and ‐susceptible volunteer oilseed rape (Brassica napus L.) to ALS inhibitors and alternative herbicides
Authors: Krato Christoph , Hartung Karin , Petersen Jan
Published: March 2012

BACKGROUND: Imidazolinone‐tolerant oilseed rape (Brassica napus L.) varieties are currently grown in Canada, North America, Chile and Australia with high acreage. A Europe‐wide introduction has started and will be pushed further for both spring and winter varieties. The primary aim of this study was to evaluate the impact of imidazolinone tolerance for future volunteer oilseed rape control in subsequent crops, particularly winter wheat.

RESULTS: A greenhouse bioassay showed cross‐tolerance of imidazolinone‐tolerant oilseed rape towards sulfonylureas, triazolopyrimidines and sulfonylaminocarbonyltriazolinones (resistance factors between 5 and 775), with a homozygous variety expressing a much higher tolerance level compared with a heterozygous variety. Calculated ED90 values suitable for controlling tolerant plants were always much higher than the recommended herbicide dose. Generally, results were confirmed under field conditions, but with higher efficacies than expected in some cases (e.g. florasulam). Herbicides with an alternative mode of action were found to be effective in controlling imidazolinone‐tolerant volunteers in subsequent winter wheat crops.

CONCLUSION: Herbicide strategies have to be adjusted for volunteer control in subsequent crops if imidazolinone‐tolerant oilseed rape varieties are to be grown. However, agronomic tools (harvest date, harvest technique, tillage) should be used conscientiously in the first place to keep volunteer oilseed rape densities at the lowest possible level. Copyright © 2012 Society of Chemical Industry
Activation of defence in sweet pepper, Capsicum annum, by cis‐jasmone, and its impact on aphid and aphid parasitoid behaviour
Authors: Dewhirst Sarah Y , Birkett Michael A , Loza‐Reyes Elisa , Martin Janet L , Pye Barry J , Smart Lesley E , Hardie Jim , Pickett John A
Published: March 2012

BACKGROUND: Two important pests of the sweet pepper, Capsicum annuum, are the peach potato aphid, Myzus persicae, and the glasshouse potato aphid, Aulacorthum solani. Current aphid control measures include the use of biological control agents, i.e. parasitic wasps, but with varying levels of success. One option to increase parasitoid efficiency is to activate plant defence. Therefore, sweet pepper plants were treated with the naturally occurring plant defence activator cis‐jasmone, and its impact upon the behaviour and development of aphids and aphid parasitoids was investigated.

RESULTS: Growth rate studies revealed that the intrinsic rate of population increase of A. solani and M. persicae on sweet pepper plants treated with cis‐jasmone (cJSP) was not affected compared with untreated plants (UnSP), but the positive behavioural response of alate M. persicae towards the volatile organic compounds (VOCs) from UnSP was eliminated by cis‐jasmone treatment 48 h previously (cJSP48). In addition, the aphid parasitoid Aphidius ervi preferred VOCs from cJSP48 compared with UnSP, and a significant increase in foraging time was also observed on cJSP. Analysis of VOCs collected from cJSP48 revealed differences compared with UnSP.

CONCLUSION: There is evidence that treatment with cis‐jasmone has the potential to improve protection of sweet pepper against insect pests. © Crown copyright 2012. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Immigration and Residential Change in Spain
Authors: Módenes Juan A. , Bayona Jordi , López‐Colás Julián
Published: March 2012

Recent foreign immigration has become the most important sociodemographic process in Spain. It impinges on many different social aspects, among them, the interrelationship between housing and population. More than 5 million immigrants have arrived during the last 10 years, responsible for about half of new households created since 2001. The size of Spanish demographic change due to immigration, as well as the predominance of a housing model based on home ownership, justifies the interest of the study. Attention will be focused on access to home ownership by long‐standing immigrants, who arrived between 1981 and 1991, observed in the 1991 and 2001 censuses, and compared with Spaniards. Their residential patterns can help us to predict the impact of the current immigration on the Spanish housing system. The conclusions point towards the beginning of a new heterogeneity in the Spanish housing system caused by a deficit of assimilation of the households with immigratory antecedents. Copyright © 2012 John Wiley & Sons, Ltd.
High‐permittivity and conduction mechanism of La‐doped Ba0.67Sr0.33TiO3 ceramics
Authors: Xu Jing , Liu HanXing , He Bo , Hao Hua , Cao MingHe
Published: March 2012

High permittivity La‐doped Ba0.67Sr0.33TiO3 ceramics (BSTL) with cubic perovskite structure, i.e., BaxSr1−xTiO3 (BST) + x at.% La, where x = 0–1, were prepared by conventional ceramic processing techniques. Dielectric characteristics, X‐ray diffraction, scanning electron microscopy (SEM), and J–V (leakage current density–voltage) behaviors were measured. Doping with the La in the BST host lattice resulted in a large‐grained (1–3 µm) and fine‐grained (0.3–1 µm) microstructure, marked raising, and broadening of the Curie peak. The temperature of dielectric peak (Tm) at 10 kHz decreased rapidly with a doping concentration of <0.7 at.% La. By means of doping with La, high dielectric constant ceramics (BSTL: 0.2 ≤ x ≤ 0.7) with permittivity at room temperature (εRT) > 110 000 at 10 kHz have been achieved. The plots of leakage current density versus voltage show the different electrical conduction mechanism in different voltage ranges.
The magnetoelectric effect and double‐perovskite structure
Authors: Bahoosh Safa Golrokh , Wesselinowa Julia M. , Trimper Steffen
Published: March 2012

Based on a microscopic model with a biquadratic magnetoelectric coupling the properties of Bi2NiMnO6 thin films are investigated. Using Green's functions the phonon spectrum is calculated which is determined by the polarization and the magnetization. The phonon energy and its damping offer a kink at the magnetic phase transition temperature. The phonon energy is enhanced if an external magnetic field is increased, whereas, the damping of the phonons decreases. The observed behavior is a strong evidence for a magnetoelectric coupling. The relevance of our approach for other multiferroics is discussed.
Surface plasmon amplification under controlled exciton‐plasmon coupling in individual carbon nanotubes
Authors: Bondarev I. V. , Antonijevic T.
Published: March 2012

We theoretically demonstrate the possibility of low‐energy surface plasmon amplification by optically excited excitons in small‐diameter carbon nanotubes. The stimulated character of such an energy transfer causes the buildup of the macroscopic population numbers of coherent localized surface plasmons. As a consequence, high‐intensity coherent optical‐frequency fields are created at nanoscale throughout the nanotube surface. These strong local fields can be used in a variety of new optoelectronic applications of carbon nanotubes, including near‐field nonlinear‐optical probing and sensing, optical switching, enhanced electromagnetic absorption, and materials nanoscale modification. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of AlInN/AlGaN distributed Bragg reflectors for high quality microcavities
Authors: Berger Christoph , Dadgar Armin , Bläsing Jürgen , Franke Alexander , Hempel Thomas , Goldhahn Rüdiger , Christen Jürgen , Krost Alois
Published: March 2012

We report on the growth of lattice‐matched AlInN/AlGaN distributed Bragg reflectors (DBRs) by metal‐organic vapor phase epitaxy. Growing these structures on a lattice‐matched AlGaN template, the formation of cracks was completely supressed and strain‐related structural degradations were avoided. A 35‐pair DBR provides a peak reflectivity of 99% at a wavelength of ∼360 nm with a stop band width of 18 nm. Thus, the DBRs are well suited for the application in high Q‐factor microcavities designed for the ultraviolet spectral region. However, spatially resolved X‐ray diffraction shows an increase of the DBR period thickness towards the edge of the wafer, leading to a strong red‐shift of the stop band of ∼35 nm. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic field effect on charge transport in π‐d system (EDT‐TTFVO)2FeBr4
Authors: Kodama Kota , Kurita Nobuyuki , Tsuchiya Satoshi , Terashima Taichi , Uji Shinya , Noguchi Satoru , Sugimoto Toyonari
Published: March 2012

Current‐voltage (I ‐V) characteristics and magnetoresistance have been measured to investigate the magnetic field effect on the charge transport in the π ‐d organic conductor (EDT‐TTFVO)2FeBr4. The I ‐V characteristics show nonlinear behavior at low temperatures, which is qualitatively explained by the transport of electrons and holes thermally excited from the charge ordered states in the EDT‐TTFVO molecule layers.

At low temperatures, the magnetoresistance has a shape change at ∼0.3 T, likely due to the spin flop transition of the 3d spins, and then a broad minimum at 7.6 T. The absence of the field angle dependence shows that the broad minimum arises mainly from the Zeeman effect, but not from the orbital effect. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Development of chiral molecular crystals
Authors: Krivickas Sara J. , Hashimoto Chiho , Takahashi Kazuyuki , Wallis John D. , Mori Hatsumi
Published: March 2012

The synthesis of enantiopure donors (R,R) and (S,S)‐vic ‐bis(hydroxymethyl)‐BEDT‐TTF (BEDT‐TTF = bis(ethylenedithio)tetrathiafulvalene) and the crystal structure of novel chiral crystal α′‐[(S,S)‐vic ‐bis(hydroxymethyl)‐BEDT‐TTF]2ClO4 is described. The charge transfer complex is chiral with the polar space group P2, which affords the possibility of pyroelectricity. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Charge disproportionation in (TMTTF)2X (X = PF6, AsF6 and SbF6) investigated by infrared spectroscopy
Authors: Knoblauch Tobias , Dressel Martin
Published: March 2012

The charge‐transfer salts (TMTTF)2X (X = PF6, AsF6 and SbF6) undergo a charge‐order transition at different temperatures TCO. We have performed infrared measurements on the ac plane with light polarized in the c direction in the temperature range from 290 down to 10 K. Below TCO, we report the splitting of the ν28 (B1u) mode including the charge sensitive C=C double bond.

From the spectra, we respectively derived a charge disproportionation of 2δ = 0.15 e, 0.21 e and 0.29 e for (TMTTF)2PF6, (TMTTF)2AsF6 and (TMTTF)2SbF6. The temperature‐dependent development of 2δ exhibits a steep increase below TCO resembling a mean‐field behaviour. We compare our results with previous infrared and NMR values. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)