bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermopiezoelectric effects on optoelectronic properties of CdTe/ZnTe quantum wires
Authors: Patil Sunil R. , Melnik R. V. N. 
Published: April 2009

AbstractWe investigate thermopiezoelectric field distributions and their effects on electronic properties of the highly strained CdTe/ZnTe quantum wires. The full 3D coupled thermoelectromechanical formulation, consisting of balance equations for heat transfer, electrostatics and the mechanical field, is developed. Effects of thermal loadings on piezoelectric fields are determined for rectangular CdTe/ZnTe quantum wire systems. The conduction band edge shifts due to thermoelectromechancial loadings are calculated. A single band Schrödinger equation is used to determine eigenstates for electrons and the analysis of classical effects are presented. Piezoelectric quantities are observed to be relatively less sensitive to thermal loadings. However, these effects are observed to be important in the determination of electronic/optoelectronic properties of quantum wire systems. The results presented here help improve our understanding of the classical effects on electronic structures and optoelectronic properties of CdTe/ZnTe quantum wires. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recombination processes and light‐induced defect creation in hydrogenated amorphous silicon
Authors: Morigaki K. 
Published: April 2009

AbstractRecombination processes of electrons and holes in hydrogenated amorphous silison (a‐Si:H) are reviewed in terms of our model. The long decay component of photoluminescence (PL) and the long decay of light‐induced electron spin resonance (LESR) are compared, and it is concluded that radiative centres responsible for the long decay component of PL are not LESR centres that are nonradiative centres. This is consistent with our model. The mechanism of light‐induced defect creation in a‐Si:H and its kinetics is summarized in terms of our model. The related defects involved in the recombination processes and the light‐induced defect creation in a‐Si:H are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation and luminescent properties of Eu2+‐activated glass ceramic phosphor precipitated with β‐Ca2SiO4 and Ca3Si2O7
Authors: Nakanishi Takayuki , Tanabe Setsuhisa 
Published: April 2009

AbstractEu2+: calcium silicate glass ceramics (GC) containing β‐Ca2SiO4 and Ca3Si2O7 crystal phosphors were fabricated by cerammization process from a GC that were prepared by a novel GC preparation; frozen sorbet method. The GC obtained (as‐made GC) consisted of glass and spherical β‐Ca2SiO4 crystal phases with size of about 20–40 μm. After post‐ceramization, Ca3Si2O7 crystals were also precipitated. Judging from the cathodoluminescence (CL) mapping images, two emission bands peaked at 515 nm and 600 nm were observed from different parts in the GC. The observed photoluminescence (PL) have two broad emission bands at 515 nm from Eu2+: β‐Ca2SiO4 and at 600 nm from Eu2+:Ca3Si2O7. With increasing heat‐treatment temperature, the color coordinates shifted from green range to center region, which corresponds to pure white in the CIE chromaticity diagram. Eu2+ doped calcium silicate GC containing β‐Ca2SiO4 and Ca3Si2O7 are suitable phosphor as the use of phosphor converting white light emitting diode (pc‐wLED) with high color rendering. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties and energy transfer in InGaAsN quantum well – InAs quantum dots tunnel injection structures for 1.3 μm emission
Authors: Rudno‐Rudziński W. , Sęk G. , Ryczko K. , Syperek M. , Misiewicz J. , Semenova E. S. , Lemaitre A. , Ramdane A. 
Published: April 2009

AbstractTunnel injection structure consisting of InAs self assembled quantum dots emitting light at the second telecom window at 1.3 μm and an InGaAsN injector quantum well is investigated by means of optical spectroscopy and the results compared to the injector‐free reference sample. The photoreflectance measurements, supported by calculations, reveal a complex structure of optical transitions in the system of coupled injector, wetting layer and strain reducing layer. The determined energy structure shows that the tunnelling is possible only through the excited states of quantum dots. Photoluminescence excitation proves the carrier transfer (tunnelling) from the injector to the dots at room temperature. The comparison of photoluminescence spectra confirms the tunnelling efficiency, especially at low temperatures. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Linearized orbital‐free embedding potential in self‐consistent calculations
Authors: Dułak Marcin , Kamiński Jakub W. , Wesołowski Tomasz A. 
Published: April 2009

AbstractConventionally, solving one‐electron equations for embedded orbitals [Eqs. (20) and (21) in Wesolowski and Warshel, J Phys Chem, 1993, 97, 8050] proceeds by a self‐consistent procedure in which the whole effective potential, including its embedding component, is updated in each iteration. We propose an alternative scheme (splitSCF), which uses the linearized embedding potential in the inner iterative loop and the outer‐loop is used to account for its deviations from linearity. The convergence of the proposed scheme is investigated for a set of weakly bound intermolecular complexes representing typical interactions with the environment. The outer loop is shown to converge very fast. No more than 3–4 iterations are needed. Errors due to skipping the outer loop completely and using the electron density obtained in the absence of the environment in the linearized embedding potential are investigated in detail. It is shown that this computationally attractive simplification, used already in numerical simulations by others, is adequate not only for van der Waals and hydrogen‐bonded complexes but even if the complex comprises charged components, i.e., where strong electronic polarization takes place. In charge‐transfer type of complexes, larger changes of electron of density upon complex formation occur and the above simplification is not recommended. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Molecular spinors suitable for four‐component relativistic correlation calculations: Studies of LaF+ and LaF using multiconfigurational quasi‐degenerate perturbation theory
Authors: Moriyama Hiroko , Tatewaki Hiroshi , Watanabe Yoshihiro , Nakano Haruyuki 
Published: April 2009

AbstractMulticonfigurational second‐order quasidegenerate perturbation theory (MCQDPT) calculations were performed for the LaF+ molecule, with one LaF2+ and four LaF+ Dirac–Fock–Roothaan (DFR) spinor sets. The best spinor set was that of LaF2+, which gave the lowest total energies and also the best excitation energies for any state considered. The MCQDPT calculations with the cation and neutral molecular spinors were also performed for LaF. The MCQDPT with the cation spinors gave the lowest total energies for all states under consideration, and the calculated excitation energies compared best with experiment. We prefer the LaF+ spinor set to those of LaF. These calculations indicate that the DFR spinor set for the (n−1) electron system is adequate for treating the molecular electronic system having n electrons. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
First‐trimester uterine artery Doppler indices in the prediction of small‐for‐gestational age pregnancy and intrauterine growth restriction
Authors: Melchiorre K. , Leslie K. , Prefumo F. , Bhide A. , Thilaganathan B. 
Published: April 2009

AbstractObjectivesTo assess the relationship of first‐trimester uterine artery Doppler indices with subsequent delivery of small‐for‐gestational age (SGA) neonates or intrauterine growth restriction (IUGR).MethodsThis was a prospective study in which uterine artery Doppler assessment was performed at 11–14 weeks in 3010 women with singleton pregnancies. Resistance indices (RI) and incidence of bilateral notching were compared between women with normal pregnancies (n = 2445) and those who delivered: SGA neonates (birth weight < 10th centile) (n = 377); SGA neonates who had been affected by pre‐eclampsia (n = 27); IUGR neonates (birth weight < 10th centile and abnormal Doppler indices) with delivery ≥ 37 weeks (n = 62); and IUGR neonates requiring preterm delivery (delivery < 37 weeks) (n = 36).ResultsThe first‐trimester uterine artery mean RI and prevalence of bilateral notching were significantly higher in women destined to deliver SGA neonates than in women with normal pregnancies (median uterine artery RI, 0.74 vs. 0.70, P < 0.001; prevalence of bilateral notches, 56% vs. 43%, P < 0.001). The areas under the receiver–operating characteristics curves for the prediction of SGA without pre‐eclampsia, IUGR, preterm IUGR and SGA with pre‐eclampsia were 0.602, 0.687, 0.776 and 0.708, respectively. There was a statistically significant inverse relationship between mean uterine artery RI and gestational age at delivery in the SGA pregnancies without pre‐eclampsia (R = − 0.329, P = 0.01).ConclusionsThere is a significant relationship between first‐trimester uterine artery Doppler RI and the subsequent development of SGA. The sensitivity of first‐trimester uterine artery Doppler is greater for SGA with pre‐eclampsia than it is for IUGR alone. This could be because these two entities may have different underlying placental abnormalities that are detected variably on first‐trimester uterine artery Doppler evaluation. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Evaluation of POSSUM for Patients Undergoing Pancreatoduodenectomy
Authors: de Castro S. M. M. , Houwert J. T. , Lagarde S. M. , Reitsma J. B. , Busch O. R. C. , van Gulik T. M. , Obertop H. , Gouma D. J. 
Published: April 2009

AbstractBackgroundComparison of operative morbidity rates after pancreatoduodenectomy between units may be misleading because it does not take into account the physiological variable of the condition of the patients. The aim of the present study was to evaluate the Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM) for pancreatoduodenectomy patients and to look for risk factors associated with morbidity in a high‐volume center.MethodsBetween January 1993 and April 2006, 652 patients underwent a pancreatoduodenectomy, 502 of them for malignant disease. POSSUM performance was evaluated by assessing the “goodness‐of‐fit” with the linear analysis method.ResultsOverall, 332 of the 652 patients (50.9%) had one or more complication after pancreatoduodenectomy, and 9 patients (1.4%) died. POSSUM had a significant lack of fit using goodness‐of‐fit analysis. In multivariate analysis, one statistically significant factor associated with morbidity and not incorporated in POSSUM (P < 0.05) was identified: ampulla of Vater adenocarcinoma (OR = 1.73, 95% CI: 1.07–2.80).ConclusionsOverall, there is a lack of calibration of POSSUM among patients who undergo pancreatoduodenectomy.
Community, Culture and Sustainability in Multilevel Dynamic Systems Intervention Science
Authors: Schensul Jean J. 
Published: April 2009

AbstractThis paper addresses intertwined issues in the conceptualization, implementation and evaluation of multilevel dynamic systems intervention science (MDSIS). Interventions are systematically planned, conducted and evaluated social science‐based cultural products intercepting the lives of people and institutions in the context of multiple additional events and processes (which also may be referred to as interventions) that may speed, slow or reduce change towards a desired outcome. Multilevel interventions address change efforts at multiple social levels in the hope that effects at each level will forge synergistic links, facilitating movement toward desired change. This paper utilizes an ecological framework that identifies macro (policy and regulatory institutions), meso (organizations and agencies with resources, and power) and micro (individuals, families and friends living in communities) interacting directly and indirectly. An MDSIS approach hypothesizes that change toward a goal will occur faster and more effectively when synchronized and supported across levels in a social system. MDSIS approaches by definition involve “whole” communities and cannot be implemented without the establishments of working community partnerships This paper takes a dynamic systems approach to science as conducted in communities, and discusses four concepts that are central to MDSIS—science, community, culture, and sustainability. These concepts are important in community based participatory research and to the targeting, refinement, and adaptation of enduring interventions. Consistency in their meaning and use can promote forward movement in the field of MDSIS, and in community‐based prevention science.
Introduction to Multi‐Level Community Based Culturally Situated Interventions
Authors: Schensul Jean J. , Trickett Edison 
Published: April 2009

AbstractThis introduction to a special issue of theAmerican Journal of Community Psychiatryis the result of a symposium at the Annual Meeting of the Society for Applied Anthropology, 2006, that brought together anthropologists and psychologists involved in community based collaborative intervention studies to examine critically the assumptions, processes and results of their multilevel interventions in local communities with local partners. The papers were an effort to examine context by offering a theoretical framework for the concept of “level” in intervention science, and advocating for “multi‐level” approaches to social/behavioral change. They presented examples of ways in which interventions targeted social “levels” either simultaneously or sequentially by working together with communities across levels, and drawing on and co‐constructing elements of local culture as components of the intervention. The papers raised a number of important issues, for example: (1) How are levels defined and how should collaborators be chosen; (2) does it matter at which level multilevel interventions begin; (3) do multilevel interventions have a greater effect on desired outcomes than level‐specific interventions; (4) are multilevel interventions more sustainable; (5) are multilevel interventions cost effective to run, and evaluate; (6) how can theories of intervention be generated and adapted to each level of a multilevel intervention; (7) how should intervention activities at each level coordinate to facilitate community resident or target population empowerment? Many of these questions were only partially addressed in the papers presented at that time, and are more fully addressed in the theoretical papers, case studies and approach to evaluation included in this collection.
The pharmacological chaperone 1‐deoxygalactonojirimycin increases α‐galactosidase A levels in Fabry patient cell lines
Authors: Benjamin E. R. , Flanagan J. J. , Schilling A. , Chang H. H. , Agarwal L. , Katz E. , Wu X. , Pine C. , Wustman B. , Desnick R. J. , Lockhart D. J. , Valenzano K. J. 
Published: April 2009

SummaryFabry disease is an X‐linked lysosomal storage disorder caused by mutations in the gene encoding α‐galactosidase A (α‐Gal A), with consequent accumulation of its major glycosphingolipid substrate, globotriaosylceramide (GL‐3). Over 500 Fabry mutations have been reported; approximately 60% are missense. The iminosugar 1‐deoxygalactonojirimycin (DGJ, migalastat hydrochloride, AT1001) is a pharmacological chaperone that selectively binds α‐Gal A, increasing physical stability, lysosomal trafficking, and cellular activity. To identify DGJ‐responsive mutant forms of α‐Gal A, the effect of DGJ incubation on α‐Gal A levels was assessed in cultured lymphoblasts from males with Fabry disease representing 75 different missense mutations, one insertion, and one splice‐site mutation. Baseline α‐Gal A levels ranged from 0 to 52% of normal. Increases in α‐Gal A levels (1.5‐ to 28‐fold) after continuous DGJ incubation for 5 days were seen for 49 different missense mutant forms with varying EC50 values (820 nmol/L to >1 mmol/L). Amino acid substitutions in responsive forms were located throughout both structural domains of the enzyme. Half of the missense mutant forms associated with classic (early‐onset) Fabry disease and a majority (90%) associated with later‐onset Fabry disease were responsive. In cultured fibroblasts from males with Fabry disease, the responses to DGJ were comparable to those of lymphoblasts with the same mutation. Importantly, elevated GL‐3 levels in responsive Fabry fibroblasts were reduced after DGJ incubation, indicating that increased mutant α‐Gal A levels can reduce accumulated substrate. These data indicate that DGJ merits further evaluation as a treatment for patients with Fabry disease with various missense mutations.
Anti‐Rancidity Effects of Sesame and Rice Bran Oils on Canola Oil During Deep Frying
Authors: Farhoosh Reza , Esmaeilzadeh Kenari Reza 
Published: April 2009

AbstractIn this study, the effect of sesame oil (SEO) and rice bran oil (RBO) on the rancidity of canola oil (CAO) during the process of frying potato pieces at 180 °C was investigated. The SEO and RBO were added to the CAO at levels of 3 and 6%. Frying stability of the oil samples during the frying process was measured on the basis of total polar compounds (TPC) content, conjugated diene value (CDV), acid value (AV), and carbonyl value (CV). In general, frying stability of the CAO significantly (P < 0.05) improved in the presence of the SEO and RBO. The positive effect of the SEO on the stability of the CAO was more than that of the RBO. Increasing the amounts of SEO and RBO from 3 to 6% led to decreases in the TPC and AV, and increases in the CDV and CV of the CAO during the frying process. The best frying performance for the CAO was obtained by use of 3% of both SEO and RBO together (CAO/SEO/RBO, 94:3:3 w/w/w).
Gelatin sponge insertion into tympanostomy tubes: An in‐vitro study to evaluate postoperative obstruction
Authors: Secor Chad P. , Wilson Robert E. , Spring Paul M. , Haydon Richard C. 
Published: April 2009

ObjectiveTo analyze the efficacy of gelatin sponge insertion into lumens of tympanostomy tubes to prevent obstruction in the presence of blood.Study DesignIn vitro model.MethodsAbsorbable gelatin sponge wicks were placed in the lumen of Ultrasil Collar Button ventilation tubes and Shepherd Grommet ventilation tubes. One half of each group was covered with blood, the other left untreated. Each tube was treated with ofloxacin solution three times daily for seven days. After treatment, the tubes were inspected. Reinspection was performed after brief suctioning. Numerical scores were given based on degree of obstruction.ResultsA statistically significant difference in degree of obstruction (P < 0.0001) was seen between all tubes with wicks alone versus those with blood added. After re‐evaluation, there remained a statistically significant difference between tubes with wicks alone and tubes with wicks and blood (P < 0.0001).ConclusionsGelatin sponge insertion does not prevent, and may in fact, enhance, obstruction of pressure equalization tube lumens in the presence of blood.
Stonehenge excavations 2008
Authors: Darvill Timothy , Wainwright Geoffrey 
Published: April 2009

AbstractThe following paper is the first published account of an excavation that took place at Stonehenge during April 2008. As this was the first excavation to take place within the stone circle for some forty years, the excavation has attracted an uncommon degree of interest, hence its publication in the Antiquaries Journal as an interim account of work in progress, in the form of an edited transcript of a paper first given at the Ordinary Meeting of the Society of Antiquaries of London on 9 October 2008. The paper explains that the 2008 excavation set out to date the construction of the Double Bluestone Circle at Stonehenge and to chart the subsequent history of the bluestones and their use at the monument. Evidence is presented for a provisional working date of around 2300 bc for the construction of the Double Bluestone Circle, while it is argued that the history of the site is far more complex than has been allowed for in existing interpretations, with a multiplicity of overlapping and intercutting (though not continuous) events, including substantial late Roman, medieval and early modern activity. The excavated material, and the evidence from the surviving stones, supports the suggestion that bluestones were brought to the site because of their perceived special qualities, perhaps for their supposed healing properties, and that some knowledge of those qualities remained current in later times with the result that in excess of two-thirds of the original bluestone volume has now disappeared.
Christopher Hawkes: his archive and networks in British and European archaeology
Authors: Díaz-Andreu Margarita , Price Megan , Gosden Chris 
Published: April 2009

AbstractThis paper reviews the contribution of Professor Christopher Hawkes, FSA, to the development of Bronze and Iron Age studies in the decades before and – more especially – after World Warii. It also provides an overview and analysis of the Hawkes Papers, kept in the Bodleian Library, and particularly of the general correspondence section, with a view to assessing the potential of this documentation for the study of the development of British prehistoric archaeology within its European context. Examination of the first thirty-one boxes of the archive situates Hawkes at the interface between several networks of individuals and communities of interest, including amateurs, professional archaeologists and his own students.
Firm Characteristics, Relative Efficiency, and Equity Returns
Authors: Nguyen Giao X. , Swanson Peggy E. 
Published: April 2009

AbstractThis study uses a stochastic frontier approach to evaluate firm efficiency. The resulting efficiency score, based on firm characteristics, is the input for performance evaluation. The portfolio composed of highly efficient firms significantly underperforms the portfolio composed of inefficient firms even after adjustment for firm characteristics and risk factors, suggesting a required premium for the inefficient firms. The difference in performance between the two portfolios remains for at least five years after the portfolio formation year. In addition, firm efficiency exhibits significant explanatory power for average equity returns in cross-sectional analysis.
Institutional Investors, Past Performance, and Dynamic Loss Aversion
Authors: O’Connell Paul G. J. , Teo Melvyn 
Published: April 2009

AbstractUsing a proprietary database of currency trades, this paper explores the effects of trading gains and losses on risk-taking among large institutional investors. We find that institutional investors, unlike individuals, are not prone to the disposition effect. Instead, institutions aggressively reduce risk following losses and mildly increase risk following gains. This asymmetry is more pronounced later in the calendar year and among older and more experienced funds. We show that such performance dependence is consistent with dynamic loss aversion (Barberis, Huang, and Santos (2001)) and overconfidence. In addition, prior institutional gains and losses have palpable implications for future prices.
The Determinants of Credit Default Swap Premia
Authors: Ericsson Jan , Jacobs Kris , Oviedo Rodolfo 
Published: April 2009

AbstractVariables that in theory determine credit spreads have limited explanatory power in existing empirical work on corporate bond data. We investigate the linear relationship between theoretical determinants of default risk and default swap spreads. We find that estimated coefficients for a minimal set of theoretical determinants of default risk are consistent with theory and are significant statistically and economically. Volatility and leverage have substantial explanatory power in univariate and multivariate regressions. A principal component analysis of residuals and spreads indicates limited evidence for a residual common factor, confirming that the theoretical variables explain a significant amount of the variation in the data.