bluuebunny/crossref_metadata_2025_split huggingface dataset:
A coaxial fed flower shaped multi‐element suspended patch antenna with illumination area in the form of a ring
Authors: Shekhar T.K. Chandra , Bhat B. 
Published: June 2010

AbstractA multi‐element suspended microstrip patch antenna with flower shaped printed pattern excited at its centre by a coaxial feed is presented. All the radiating patch elements are electromagnetically coupled symmetrically to the same coaxial feed, thereby eliminating the need for a separate power division network. With three or more elements, the antenna beam illuminates an area in the form of a ring symmetric about the axis perpendicular to the plane of the patch elements. The antenna offers a gain in the range 5–6 dBi with a 3 dB beamwidth of about 50° in any cross‐sectional plane passing through the vertical axis. Details of the simulation studies carried out on the antenna with one to five elements and experimental results on the fabricated antennas are presented. The antenna has potential applications in remote sensing and biomedical areas, particularly for microwave imaging. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 2037–2043, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25418
Compact narrow band‐pass filter with λG/4 short stubs using impedance mismatching of the transmission line
Authors: Yoon Ki‐Cheol , Kim Jeonggon Harrison , Lee Jong‐Chul 
Published: June 2010

AbstractIn this article, a narrow band pass filter with reduced size using the λg/4 short stubs is presented.The filter size is reduced by realization of transmission line at the second harmonic while the power can be transferred to the output using the fundamental frequency band generated in the resonator and the transmission line in which the impedance mismatching technique is adopted. The experimental results show that the insertion loss is 2.0 dB and return loss is 11.1 dB, and the fractional bandwidth is 10% at the center frequency of 5.8 GHz. The filter size is 19.7 × 8.6 mm2. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 2002–2005, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25419
Echo planar correlated spectroscopic imaging: Implementation and pilot evaluation in human calf in vivo
Authors: Lipnick Scott , Verma Gaurav , Ramadan Saadallah , Furuyama Jon , Thomas M. Albert 
Published: June 2010

AbstractExploiting the speed benefits of echo‐planar imaging (EPI), the echo‐planar spectroscopic imaging (EPSI) sequence facilitates recording of one spectral and two to three spatial dimensions faster than the conventional magnetic resonance spectroscopic imaging (MRSI). A novel four dimensional (4D) echo‐planar correlated spectroscopic imaging (EP‐COSI) was implemented on a whole body 3 T MRI scanner combining two spectral with two spatial encodings. Similar to EPSI, the EP‐COSI sequence used a bipolar spatial read‐out train facilitating simultaneous spatial and spectral encoding, and the conventional phase and spectral encodings for the other spatial and indirect spectral dimensions, respectively. Multiple 2D correlated spectroscopy (COSY) spectra were recorded over the spatially resolved volume of interest (VOI) localized by a train of three slice‐selective radiofrequency (RF) pulses (90°–180°–90°). After the initial optimization using phantom solutions, the EP‐COSI data were recorded from the lower leg of eight healthy volunteers including one endurance trained volunteer. Pilot results showed acceptable spatial and spectral quality achievable using the EP‐COSI sequence. There was a detectable separation of cross peaks arising from the skeletal muscle intramyocellular lipids (IMCLs) and extramyocellular lipids (EMCLs) saturated and unsaturated pools. Residual dipolar interaction between the N‐methylene and N‐methyl protons of creatine/phosphocreatine (Cr/PCr) was also observed in the tibialis anterior region. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
RF excitation using time interleaved acquisition of modes (TIAMO) to address B1 inhomogeneity in high‐field MRI
Authors: Orzada Stephan , Maderwald Stefan , Poser Benedikt Andreas , Bitz Andreas K. , Quick Harald H. , Ladd Mark E. 
Published: June 2010

AbstractAs the field strength and, therefore, the operational frequency in MRI is increased, the wavelength approaches the size of the human head/body, resulting in wave effects, which cause signal decreases and dropouts. Several multichannel approaches have been proposed to try to tackle these problems, including RF shimming, where each element in an array is driven by its own amplifier and modulated with a certain (constant) amplitude and phase relative to the other elements, and Transmit SENSE, where spatially tailored RF pulses are used. In this article, a relatively inexpensive and easy to use imaging scheme for 7 Tesla imaging is proposed to mitigate signal voids due to B field inhomogeneity. Two time‐interleaved images are acquired using a different excitation mode for each. By forming virtual receive elements, both images are reconstructed together using GRAPPA to achieve a more homogeneous image, with only small SNR and SAR penalty in head and body imaging at 7 Tesla. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Cystic fibrosis related diabetes
Authors: Alexander S , Bridges N 
Published: June 2010

AbstractCystic fibrosis related diabetes is the most common co‐morbidity in cystic fibrosis. Insulin deficiency is the key factor in the development of cystic fibrosis related diabetes, which is associated with worse pulmonary and nutritional morbidity and increased mortality.The oral glucose tolerance test remains standard for screening, but continuous glucose monitoring systems are increasingly used to help with screening and management.Insulin is the only treatment with evidence of benefit. The timing of insulin treatment, and the level of glycaemia for which to aim, are areas which need further research.Treatment is aimed at both optimising nutrition and lung function and reducing the risk of microvascular complications. Copyright © 2010 John Wiley & Sons.
Validation of the mPW1PW Quantum chemical calculations for the vibrational study of organic molecules – re‐assignment of the isopropylamine vibrational spectra
Authors: Padrão Sara , Fiuza Sónia M. , Amado Ana M. , Amorim da Costa António M. , Batista de Carvalho Luis A. E. 
Published: June 2010

AbstractThe validity of the mPW1PW91 density functional theory (DFT) method coupled to the all‐electron basis set 6‐31G* (mPW1PW/6‐31G*) for the study of amines, using isopropylamine (iPram) as a case study, was evaluated. Validation was performed by comparing the calculated values with the corresponding experimental results obtained and/or reported in the literature. Moreover, the accuracy of that theoretical level was compared with that of other widely used theoretical levels, namely HF/6‐31G*, B3LYP/6‐31G* and MP2/6‐31G*. The effect of basis set improvement within the mPW1PW protocol was evaluated considering the widely used 6‐311G** basis set. On the whole, the results clearly show that the mPW1PW/6‐31G* calculations are a suitable tool for the prediction of the structural and vibrational features of iPram. The validation of the theoretical methodology allowed a complete revision of the vibrational assignments previously reported in the literature, being the result of several proposed re‐assignments. Copyright © 2010 John Wiley & Sons, Ltd.
An Open Argon Dielectric Barrier Discharge VUV‐Source
Authors: Sobottka Axel , Drößler Lutz , Lenk Martin , Prager Lutz , Buchmeiser Michael R. 
Published: June 2010

AbstractAn argon vacuum ultra violet (VUV) light lamp was built. The radiation source is driven by an RF generator in continuous wave (cw) mode at frequencies of 680 and 840 kHz, respectively. An optimum design was developed for an atmospheric pressure glow discharge in an open system. The UV power of the radiation source was measured and the time response of the dielectric discharge was investigated. Finally, the emission spectra were measured under different conditions. All components of the lamp were designed in way that they meet the requirements for a practical setup for the irradiation of miscellaneous samples for both surface modification and activation.magnified image
Recent developments in linear and nonlinear near‐field microscopy on single plasmonic nanoparticles
Authors: Duò Lamberto , Biagioni Paolo , Finazzi Marco 
Published: June 2010

AbstractPlasmonic circuits constituted of several interacting optical elements require new means to characterize their response down to the single particle level, both in amplitude and phase. To this aim, scanning near‐field optical microscopy (SNOM) allows for sub‐diffraction resolution, but requires a deep understanding of the physical processes at the basis of image formation. In this paper, we briefly review recent developments in the linear and nonlinear near‐field characterization of single plasmonic resonators. On the one hand, linear scattering processes are governed by interference between light propagating out of the SNOM aperture and that radiated by the plasmonic scatterer, thus bearing signatures of both amplitude and phase of the particle response. On the other hand, nonlinear investigations are dominated by local field enhancements, and are thus best suited to image the spatial distribution of the plasmon modes sustained by the resonator. The combined use of the two techniques, therefore, allows for a complete analysis of both the scattering response and the local field distribution near resonant plasmonic nanoparticles.
Optical properties of nanostructured metamaterials
Authors: Cortes Ernesto , Mochán Luis , Mendoza Bernardo S. , Ortiz Guillermo P. 
Published: June 2010

AbstractWe present a very efficient recursive method to calculate the effective optical response of nanostructured metamaterials made up of particles with arbitrarily shaped cross sections arranged in periodic two‐dimensional arrays. We consider dielectric particles embedded in a metal matrix with a lattice constant much smaller than the wavelength. Neglecting retardation our formalism allows factoring the geometrical properties from the properties of the materials. If the conducting phase is continuous the low frequency behavior is metallic. If the conducting paths are nearly bloqued by the dielectric particles, the high frequency behavior is dielectric. Thus, extraordinary‐reflectance bands may develop at intermediate frequencies, where the macroscopic response matches vacuum. The optical properties of these systems may be tuned by adjusting the geometry.magnified image Sketch of a nanostructured metamaterial slab with a dielectric‐like or metallic‐like behavior depending on the frequency of the incoming light.
Theory of the temperature dependent dielectric function of semiconductors: from bulk to surfaces. Application to GaAs and Si
Authors: Shkrebtii Anatoli I. , Ibrahim Zahraa A. , Teatro Timothy , Richter Wolfgang , Lee Martin J.G. , Henderson Laura 
Published: June 2010

AbstractA novel, efficient method for calculating the temperature dependencies of the linear dielectric functions of semiconductor systems and its application are presented. The method follows an intuitive and natural path withab‐initiofinite temperature molecular dynamics providing the thermally perturbed atomic configurations, which are used as structural inputs for calculating the dielectric function. The effect of lattice dynamics, including quantum zero point vibration, on the electronic bands and dielectric function of crystalline (c‐) GaAs and Si as well as hydrogenated amorphous Si (a‐Si:H) is discussed. Our theoretical results for bulk c‐GaAs and c‐Si in the range from 0 to 1000 K are in good overall agreement with highly accurate ellipsometric measurements. The implementation of the method resolves a serious discrepancy in energy and line shape between experiment and the latest optical models, all of which neglect lattice dynamics, and provides information on the indirect gap and indirect optical transitions in c‐Si. For a‐Si:H, the calculated temperature dependent optical response combined with the vibrational spectroscopy provides detailed insight into electronic, dynamical properties, and stability of this important prototypical amorphous semiconductor material. At semiconductor surfaces, dynamical effects are expected to be even more pronounced due to reduced atom coordination and reconstruction. This is demonstrated for C(111) 2 × 1, an intensively studied but controversial surface of the quantum diamond crystal.
Vibrational properties of sp carbon atomic wires in cluster‐assembled carbon films
Authors: Onida Giovanni , Manini Nicola , Ravagnan Luca , Cinquanta Eugenio , Sangalli Davide , Milani Paolo 
Published: June 2010

AbstractLinear chains made by a single row of sp‐hybridized carbon are predicted to display fascinating mechano‐electronic properties connected with their termination and stabilization inside realistic carbon structures. The present work describes how the computed vibrational properties of cumulenic and polyynic carbon chains allow one to interpret the carbynic features observed in Raman spectra of cluster‐assembled sp–sp2 films. The overall picture is consistent with the measured decay of the components induced by air or oxygen exposure.magnified image
The electronic properties of carbon atomic chains attached to the edges of graphitic fragments can be controlled by a relative twist of the terminating planes.
A slave‐boson mean‐field theory for general multi‐band Hubbard models
Authors: Bünemann J. 
Published: June 2010

AbstractWe introduce a new slave‐boson mean‐field theory which allows the investigation of general multi‐band Hubbard models. Unlike earlier attempts of such a generalization, in our approach the quantum‐mechanical problem is exactly reformulated in an extended Hilbert space of Fermions and Bosons before a mean‐field approximation is applied. Systems with superconducting order parameters are naturally included in our formalism. Our ground‐state energy functional agrees with the corresponding quantity derived within the Gutzwiller theory.
Electrical properties of C60 delta‐doped GaAs and AlGaAs layers grown by MBE
Authors: Nishinaga Jiro , Hayashi Takashi , Hishida Kiyoshi , Horikoshi Yoshiji 
Published: June 2010

AbstractC60 δ‐doped GaAs and AlGaAs layers are grown by migration enhanced epitaxy method. Sticking coefficients of C60 on GaAs and AlGaAs surfaces and electrical characteristics of the layers are investigated by secondary ion mass spectroscopy (SIMS) and electrochemical capacitance voltage (ECV) measurements. SIMS profiles indicate that the layers have well‐defined δ‐doped structures, and the sticking coefficients of C60 on GaAs and AlGaAs surfaces are confirmed to be sufficiently high. ECV profiles of C60 δ‐doped GaAs and AlGaAs layers suggest that C60 molecules in GaAs and AlGaAs lattices produce electron traps which can be charged or discharged by applied electric fields. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic layer epitaxy of AlGaN
Authors: Nagamatsu Kentaro , Iida Daisuke , Takeda Kenichiro , Nagata Kensuke , Asai Toshiaki , Iwaya Motoaki , Kamiyama Satoshi , Amano Hiroshi , Akasaki Isamu 
Published: June 2010

AbstractAtomic layer epitaxy of AlGaN with an average growth rate of as high as 4.5 mm/h has been achieved by the high‐speed switching‐valves (HSSVs) technique in a raised‐pressure metalorganic vapor phase epitaxy system. Regarding the duration of group III metalorganics and NH3 gases input, 0.1 second for each injection time is found to be sufficient to realize AlGaN growth of one monolayer per cycle over a 2‐inch wafer with hydrogen and nitrogen carrier gases at a raised pressure. Low‐temperature growth of high‐quality AlGaN has been achieved using HSSVs. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integrating sustainable waste management into product design: sustainability as a functional requirement
Authors: Deutz Pauline , Neighbour Gareth , McGuire Michael 
Published: June 2010

AbstractMunicipal waste management is, by definition, spatially organized. In the United Kingdom the national government designates waste collection and disposal responsibilities to the various scales of local government. However, whilst the highest aim of waste management is prevention, achieving this is beyond the scope of local authorities, which deal with the waste stream presented to them as an independent variable. Alternatively, product design offers a potential point of policy intervention, by which the waste stream becomes a dependent variable. This paper innovatively argues that, for eco‐design to be effective, sustainable waste management must be established as a functional requirement in the design process. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Selective measurement of the electronic states of the steps on rutile TiO2 (15 15 4) surface by optical second harmonic spectroscopy
Authors: Takahashi Hiroaki , Watanabe Ryosuke , Mizutani Goro 
Published: June 2010

AbstractWe have obtained optical second harmonic spectra of stepped rutile TiO2 (15 15 4) adsorbed with formic acid HCOOH. We have achieved selective measurement of the electronic states of the bunched steps on this surface in an optical configuration with nearly normal incident laser illumination. For the polarization combinations S in‐S out and P in‐S out, the SH intensity was higher near the second harmonic photon energy 3.6 eV and also above 4.45 eV. The terraces and steps were found to show remarkably different contributions to the optical second harmonic spectra at 45° incidence. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of annealing on AlN/GaN quantum dot heterostructures: advanced ion beam characterization and X‐ray study of low‐dimensional structures
Authors: Magalhães S. , Lorenz K. , Franco N. , Barradas N. P. , Alves E. , Monteiro T. , Amstatt B. , Fellmann V. , Daudin B. 
Published: June 2010

AbstractMultilayers consisting of six GaN quantum dot (QD) layers separated by AlN spacer layers were grown by molecular beam epitaxy. Structural properties and the effects of thermal annealing were analyzed using X‐ray diffraction (XRD), X‐ray reflection (XRR) and Rutherford backscattering spectrometry/Channeling (RBS/C). Annealing was performed in nitrogen atmosphere for 20 min at temperatures between 1000 and 1200 °C.The GaN QDs on the surface were destroyed at temperatures ≥ 1100 °C while the AlN spacer layers protected the deeper lying QD layers. The multilayer structure was well preserved for all studied temperatures. Indications of interdiffusion in the interfaces were found. Thickness fluctuations were evidenced by XRR. Copyright © 2010 John Wiley & Sons, Ltd.
Nonbiofouling surface based on amphiphilic alkanethiol self‐assembled monolayers
Authors: Feng Shijun , Huang Yangen , Wang Qiang , Qing Feng‐Ling 
Published: June 2010

AbstractA series of novel amphiphilic alkanethiols used for preparation of nonbiofouling surfaces have been synthesized and characterized. Surface properties of the resultant self assembled layers have been studied by multiple characterization techniques, such as XPS, Grazing angle infrared spectroscopy (GA‐FTIR) and contact angle measurements. The antifouling performance of surfaces grafted with terminally fluorinated alkanethiols were assayed employing the fouling diatom Nitzschia and ubiquitous Staphylococcus aureus. The results indicated that amphiphilic alkanethiol‐grafted surfaces could effectively reduce the bacterial adhesion and settlement of the fouling diatom. Copyright © 2010 John Wiley & Sons, Ltd.
Surface structure of cationic surfactant solutions investigated by angular resolved X‐ray photoelectron spectroscopy with calibrated transmission function
Authors: Wang Chuangye , Morgner Harald 
Published: June 2010

AbstractThe main goal of the present work is to investigate the surface structure of cationic surfactant solutions by angular resolved X‐ray photoelectron spectroscopy (ARXPS) after calibrating transmission function of the spectrometer. We have estimated the transmission function of the ARXPS spectrometer, and with it, we investigated solution of tetrabutylammonium iodide in a nonaqueous polar solvent. By genetic algorithm, the fractional concentration‐depth profiles of constituents were reconstructed. These depth profiles evidence the enrichment of surfactant and the depletion of solvent in the surface regime and verify the separate distributions of oppositely charged surfactant ions. From those profiles we draw a conclusion that there is a preferred orientation for cation present at the surface, and the possibility for cation to take this orientation is related to its surface amount. Copyright © 2010 John Wiley & Sons, Ltd.
Estimation of relative risk and prevalence ratio
Authors: Savu Anamaria , Liu Qi , Yasui Yutaka 
Published: June 2010

AbstractRelative risks (RRs) and prevalence ratios (PRs) are measures of association that are more intuitively interpretable than odds ratios (ORs). Many health science studies report OR estimates, however, even when their designs permit and study questions target RRs and/or PRs. This is, partially, attributable to the popularity and technical advantage (i.e. no restriction on the parameter space) of logistic regression for estimating ORs. To improve this practice, several biostatistical approaches for estimating RR/PR, adjusting for potential confounders, have been proposed. In this paper, we consider two RR/PR estimating methods: (1) the modification of log‐binomial regression with the COPY method; and (2) an inverse‐probability‐of‐treatment‐weighted (IPTW) log‐binomial regression we newly propose. For the COPY method, we rigorously establish the existence and uniqueness of the maximum‐likelihood estimator, provided certain degeneracies in the data do not occur. Moreover, the global maximum of the COPY‐modified likelihood is shown to occur at an interior point of the restricted parameter space. This result explains why the COPY method avoids convergence problems of log‐binomial models frequently. For the IPTW estimator, we show that its simple procedure results in standardized estimates of RR/PR, and discuss its potential challenges, extensions, and an improvement through propensity‐score‐based grouping of observations. Furthermore, we compare the performances of four RR/PR estimation methods, including the COPY method and IPTW log‐binomial regression, on simulated data. We demonstrate a lack of robustness of the COPY method against misspecification of the true relationship between binary outcome and explanatory variables, and show robustness of the IPTW approach in this regard. Copyright © 2010 John Wiley & Sons, Ltd.
Chestnut and acorn starch properties affected by isolation methods
Authors: Correia Paula Reis , Beirão‐da‐Costa Maria Luísa 
Published: June 2010

AbstractStarches from chestnut (Castanea sativa Mill.) and acorns (Quercus suber Lam. and Q. rotundifolia Lam.) were isolated from dried fruits using four different methods. These involved a physicochemical and/or an enzymatic treatment followed by centrifugation and sieving: (i) low shear at alkaline pH – LSA, (ii) high shear in water – HSW, (iii) enzymatic treatment at low shear – LSE, (iv) LSA and using successively three sieves – LSA3S. Raw yield, purity, colour parameters, morphology, protein, fat, ash, reducing sugars and amylose contents, damaged starch content and viscoamylographic profiles were studied in isolated starches, presenting different properties through different methods. In general, chestnut starch seems to be poorly resistant to extraction methodologies as shown by the damaged starch content and viscoamylographic properties encountered during this study. Moreover, acorn starches exhibited cross‐linked amylographic patterns. For all the tested raw materials, the LSA3S isolation method always higher yield and purity of starches. Gelatinization temperature and peak consistency were also higher than those shown by starches produced by the other methods, a less damaged structure was also evident. In conclusion, it seems that this method is the most suitable to produce starch for food ingredient usage.