bluuebunny/crossref_metadata_2025_split huggingface dataset:
IMPLIED VOLATILITY AND THE RISK‐RETURN RELATION: A NOTE
Authors: Kanas Angelos 
Published: March 2012

ABSTRACTA 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

AbstractIn 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

AbstractWhispering 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

AbstractChanges 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

AbstractIn 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.
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

AbstractSimultaneous 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

ABSTRACTSelection 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.
Localization and scheduling protocols for actor‐centric sensor networks
Authors: Das Sajal K. , Ghidini Giacomo , Navarra Alfredo , Pinotti Cristina M. 
Published: March 2012

AbstractWe 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

SUMMARYBy 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

SUMMARYThis 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

AbstractBACKGROUND: 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

AbstractBACKGROUND: 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

ABSTRACTRecent 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

AbstractHigh 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

AbstractBased 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

AbstractWe 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)