bluuebunny/crossref_metadata_2025 huggingface dataset:
Intergenerational transmission of educational attainment: Three levels of parent–child communication as mediators
Authors: Chi Liping
Published: December 2012

Although the intergenerational transmission of educational attainment has been confirmed by many researchers, its mechanism still remains controversial. Parent–child communication has been regarded as one of the important mediators. The present study primarily aimed to examine the potentially mediating role of parent–child communication in the transmission of educational attainment, based on a sample of 366 Chinese fifth and sixth graders. Parent–child communication was measured against the three levels of the parents' communication ability, the quality of the father–child and mother–child communications, and the relation between the two dyadic communications. The results duplicated the positive effect of parents' educational attainment on children's academic achievement. Moreover, it was found that parents' communication ability alone played a mediating role, and that the three levels of parent–child communication constructed a “mediator chain” between the parents' educational attainment and the children's academic achievement. Finally, the intergenerational transmission of educational attainment in China and the mediating role of the three levels of parent–child communication were discussed.
Measuring adult Attention Deficit Hyperactivity Disorder using the Quantified Behavior Test Plus
Authors: Edebol Hanna , Helldin Lars , Norlander Torsten
Published: December 2012

Attention Deficit Hyperactivity Disorder (ADHD) occurs in approximately 5% of the adult population and includes cardinal symptoms of hyperactivity, inattention, and impulsivity that may be difficult to identify with clinical routine methods. Continuous performance tests are objective measures of inattention and impulsivity that, combined with objective measures of motor activity, facilitate identification of ADHD among adults. The aim of the present study was to examine the sensitivity, specificity, and a composite measure of ADHD using objective measures of the ADHD‐cardinal symptoms in adult participants with ADHD and non‐ADHD normative participants. Cardinal symptoms were measured in 55 participants having ADHD, 202 non‐ADHD normative participants, as well as 84 ADHD normative participants using the Quantified Behavior Test Plus. This test measures inattention and impulsivity using a continuous performance test, and hyperactivity using a motion‐tracking system. A predictive variable for the detection of ADHD called Prediction of ADHD yielded 86% sensitivity and 83% specificity. A composite measure of ADHD cardinal symptoms was developed using a Weighed Core Symptoms scale that indicated the total amount of ADHD symptoms on a numeric scale from 0 to 100. The total amount of ADHD symptoms was measured on a scale and predicted with the categorical variable in a majority of the cases in the present study. Further studies are needed in order to confirm the results with regard to additional clinical and normative samples. Careful consideration of potential sex and diagnostic subtype differences are noteworthy aspects for future examinations of the new instruments.
Investigating differences in treatment effect estimates between propensity score matching and weighting: a demonstration using STAR*D trial data
Authors: Ellis Alan R. , Dusetzina Stacie B. , Hansen Richard A. , Gaynes Bradley N. , Farley Joel F. , Stürmer Til
Published: December 2012

Purpose

The choice of propensity score (PS) implementation influences treatment effect estimates not only because different methods estimate different quantities, but also because different estimators respond in different ways to phenomena such as treatment effect heterogeneity and limited availability of potential matches. Using effectiveness data, we describe lessons learned from sensitivity analyses with matched and weighted estimates.

Methods

With subsample data (N = 1292) from Sequenced Treatment Alternatives to Relieve Depression, a 2001–2004 effectiveness trial of depression treatments, we implemented PS matching and weighting to estimate the treatment effect in the treated and conducted multiple sensitivity analyses.

Results

Matching and weighting both balanced covariates but yielded different samples and treatment effect estimates (matched RR 1.00, 95% CI: 0.75–1.34; weighted RR 1.28, 95% CI: 0.97–1.69). In sensitivity analyses, as increasing numbers of observations at both ends of the PS distribution were excluded from the weighted analysis, weighted estimates approached the matched estimate (weighted RR 1.04, 95% CI 0.77–1.39 after excluding all observations below the 5th percentile of the treated and above the 95th percentile of the untreated). Treatment appeared to have benefits only in the highest and lowest PS strata.

Conclusions

Matched and weighted estimates differed due to incomplete matching, sensitivity of weighted estimates to extreme observations, and possibly treatment effect heterogeneity. PS analysis requires identifying the population and treatment effect of interest, selecting an appropriate implementation method, and conducting and reporting sensitivity analyses. Weighted estimation especially should include sensitivity analyses relating to influential observations, such as those treated contrary to prediction. Copyright © 2012 John Wiley & Sons, Ltd.
Tracking control of high‐concentration photovoltaic systems for minimizing power losses
Authors: Kim Yong Sin , Kang Sung‐Mo , Winston Roland
Published: December 2012

This paper presents three key factors that cause system mismatches and power losses in high‐concentration photovoltaic (HCPV) systems. The first factor is the I–V mismatch within a module, similar to the manufacturing mismatches in conventional photovoltaic modules. The second factor is the misalignments amongst modules, and the third factor is the tracking control. Unlike in the conventional photovoltaic systems, the second and the third factors in HCPV systems introduce larger electro‐optical mismatches due to narrow acceptance angles. We have developed a model to address these three factors. It allows an accurate estimation of power losses in HCPV systems, which enabled us to propose configurations to reduce power losses without adding additional electrical components to the system. Simulation results show that the power harvest can be increased as much as 8.5% for a system using open‐loop controls by simply increasing the number of strings at the time of calibration. Experimental test results are presented for validation. Copyright © 2012 John Wiley & Sons, Ltd.
Thermokarst Lake Morphometry and Erosion Features in Two Peat Plateau Areas of Northeast European Russia
Authors: Sjöberg Ylva , Hugelius Gustaf , Kuhry Peter
Published: December 2012

High‐resolution satellite remote sensing analysis (n = 637 lakes) and field measurements (n = 29 lakes) of two peat plateau areas in northeast European Russia were carried out to investigate lake morphology, map shoreline erosion indicators and assess possible orientation patterns in lake and shore morphology. The study includes the first detailed characterisation of the shape and size of thermokarst lakes in organic terrain. The area covered by lakes is 7.0 per cent and 13.6 per cent, and median lake size is 184 m2 and 265 m2, respectively, for the two study areas. In both areas, most lakes have a similar northwest to southeast orientation, and shores most commonly face northeast or southwest. The shores are generally steeper and have more cracks and lake depths are greater along shores facing northeast or southeast, and along the shorelines of larger lakes. Shores with a peat substrate are more heterogeneous than those with a mineral substrate in terms of steepness, cracks and water depths. Since the lakes are generally small, the shoreline/area ratio is high and a large part of the peat plateau areas can potentially be affected by shoreline erosion. Copyright © 2012 John Wiley & Sons, Ltd.
Standardized Aqueous Tribulus terristris (Nerunjil) Extract Attenuates Hyperalgesia in Experimentally Induced Diabetic Neuropathic Pain Model: Role of Oxidative Stress and Inflammatory Mediators
Authors: Ranjithkumar Ravichandran , Prathab Balaji S. , Balaji Bhaskar , Ramesh R. V. , Ramanathan Muthiah
Published: December 2012

The present study aimed to evaluate standardized aqueous Tribulus terristris (nerunjil) extract on the pain threshold response in streptozotocin (STZ)‐induced diabetic neuropathic pain model in rats. After a single injection of STZ (40 mg/kg; i.p.), Wistar male rats were tested by the thermal and chemical‐induced pain models. Diabetic rats exhibited significant hyperalgesia, and these rats were left untreated for the first four weeks. Thereafter, treatment was initiated and continued up to week‐8. All the rats except the vehicle‐treated group received insulin 5 IU/kg/day to maintain plasma glucose levels. Treatment with nerunjil (100 and 300 mg/kg; p.o.) for 4 weeks significantly attenuated the nociception in behavioural models. Nerunjil also inhibited the tumour necrosis factor‐α and interleukin‐1 beta levels. The effect of nerunjil (300 mg/kg) is comparable to the standard drug Pregabalin (100 mg/kg). Nerunjil increased the superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione, and decreased the lipid peroxide levels in dose‐dependent manner. Insulin alone‐treated rats failed to attenuate hyperalgesic response. In comparison to insulin alone‐treated rats, nerunjil exhibited significant increase in the pain threshold response. It could be concluded that in controlled diabetic states, nerunjil attenuated the neuropathic pain through modulation of oxidative stress and inflammatory cytokine release. Copyright © 2012 John Wiley & Sons, Ltd.
Antimicrobial, antioxidant and anti‐inflammatory activity of young shoots of the smoke tree, Cotinus coggygria Scop
Authors: Marčetić Mirjana , Božić Dragana , Milenković Marina , Malešević Nevenka , Radulović Siniša , Kovačević Nada
Published: December 2012

In this study, we investigated the antimicrobial activity of the young shoots of the smoke tree, Cotinus coggygria Scop., Anacardiaceae. The acetone extract and the derived ethyl acetate fraction effectively inhibited the growth of Gram‐positive and Gram‐negative bacteria (MIC 25–200 µg/ml), while the chloroform fraction showed pronounced activity against the yeast Candida albicans (MIC 3.12 µg/ml). The ethyl acetate fraction exhibited a significant ferric‐reducing ability (10.7 mmol Fe2+/g extract), a very high DPPH radical scavenging activity (SC50 = 1.7 µg/ml) and inhibition of lipid peroxidation (IC50 = 41.8 µg/ml). High amounts of total phenolics (929.8 mg/g), tannins (833.8 mg/g) and flavonoids (35.5 mg/g) were determined in the ethyl acetate fraction, which also exerted significant anti‐inflammatory (76.7%) and cytotoxic effects (IC50 = 15.6 µg/ml). Copyright © 2012 John Wiley & Sons, Ltd.
Migration Prediction Model of Residual Contaminants from Food Packaging Paper and its Experimental Verification
Authors: Huang Chong‐Xing , Duan Dan‐Dan , Yan Meng‐Meng , Wang Shuang‐Fei
Published: December 2012

A migration prediction model of residual contaminants from food packaging paper was established on the basis of one‐dimensioned Fick's diffusion theory, and analytical solutions were obtained by inducing paper porosity and the adsorption quantity of pollutants. In addition, the migration of the six contaminants, namely styrene, diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, dioctyl phthalate and bisphenol A in three kinds of food packaging paper(Kraft, white cardboard and imitation parchment) into different food stimulants was studied. In this study, the diffusion coefficient and the partition coefficient of these six contaminants in those papers were measured by experiments, and the experimental migration data and calculated values based on the model were analyzed. The results show that paper porosity affects the migration of contaminants so significantly that it is necessary to set it as a parameter in the analysis model. The experiment results agreed with the theoretical prediction values when the temperature was set approximately at 25°C. Copyright © 2012 John Wiley & Sons, Ltd.
Ensemble spread‐based assessment of observation impact: application to a global ocean analysis system
Authors: Storto Andrea , Masina Simona , Dobricic Srdjan
Published: December 2012

This article explores an ensemble strategy for evaluating the impact of different observing networks. The impact is represented by the relative ensemble spread increase, in model space, of data‐denial ensemble simulations with respect to an ‘all‐observation’ ensemble experiment, evaluated independently for each observing network. The forecast‐error covariance intercomparison reduces to the ensemble spread intercomparison; thus, the method can be applied to any assimilation system and requires only the proper construction of an ensemble system, although the impact assessment results depend on the specific configuration of the investigated analysis system. Our approach allows us to determine the impact of the observing networks in model space (unlike Observing System Experiments) and for different forecast ranges of the ocean general circulation model. No tangent‐linear and adjoint coding of the ocean model are required. The method is applied for demonstration to a large‐scale global ocean variational analysis system. The ensemble members are generated by (i) perturbing the observations within the 3D‐Var assimilation scheme, (ii) perturbing the surface forcing, and (iii) stochastically perturbing the ocean model parametrisation tendencies. The impact is calculated for CTDs, XBTs, moorings, Argo, sea‐level anomaly observations and sea‐surface temperature measurements from space‐borne microwave instruments within the three‐year period from January 2003 to December 2005. It turns out, on the global scale, that altimetry exhibits the largest impact on near‐surface temperature and sea‐surface height. In contrast, deep‐ocean impacts are led by the Argo float network. As expected, space‐borne observations (sea‐level anomaly and sea‐surface temperature observations) increase their impact in the Southern Ocean, due to the lack of a robust network ofin situobservations. The results of the impact on the salinity indicate the great importance of Argo floats, especially in the northern Extratropics.
On a greedy 2‐matching algorithm and Hamilton cycles in random graphs with minimum degree at least three
Authors: Frieze Alan
Published: December 2012

We describe and analyse a simple greedy algorithm 2greedy that finds a good 2‐matching M in the random graph when . A 2‐matching is a spanning subgraph of maximum degree two and G is drawn uniformly from graphs with vertex set , cn edges and minimum degree at least three. By good we mean that M has components. We then use this 2‐matching to build a Hamilton cycle in time w.h.p. © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 45, 443‐497, 2014
Empirical Bayes ranking and selection methods via semiparametric hierarchical mixture models in microarray studies
Authors: Noma Hisashi , Matsui Shigeyuki
Published: December 2012

The main purpose of microarray studies is screening of differentially expressed genes as candidates for further investigation. Because of limited resources in this stage, prioritizing genes are relevant statistical tasks in microarray studies. For effective gene selections, parametric empirical Bayes methods for ranking and selection of genes with largest effect sizes have been proposed (Nomaet al., 2010;Biostatistics11: 281–289). The hierarchical mixture model incorporates the differential and non‐differential components and allows information borrowing across differential genes with separation from nuisance, non‐differential genes. In this article, we develop empirical Bayes ranking methods via a semiparametric hierarchical mixture model. A nonparametric prior distribution, rather than parametric prior distributions, for effect sizes is specified and estimated using the “smoothing by roughening” approach of Laird and Louis (1991;Computational Statistics and Data Analysis12: 27–37). We present applications to childhood and infant leukemia clinical studies with microarrays for exploring genes related to prognosis or disease progression. Copyright © 2012 John Wiley & Sons, Ltd.
Incremental inconsistency detection with low memory overhead
Authors: Falleri Jean‐Rémy , Blanc Xavier , Bendraou Reda , da Silva Marcos Aurélio Almeida , Teyton Cédric
Published: December 2012

Ensuring models’ consistency is a key concern when using a model‐based development approach. Therefore, model inconsistency detection has received significant attention over the last years. To be useful, inconsistency detection has to be sound, efficient, and scalable. Incremental detection is one way to achieve efficiency in the presence of large models. In most of the existing approaches, incrementalization is carried out at the expense of the memory consumption that becomes proportional to the model size and the number of consistency rules. In this paper, we propose a new incremental inconsistency detection approach that only consumes a small and model size‐independent amount of memory. It will therefore scale better to projects using large models and many consistency rules. Copyright © 2012 John Wiley & Sons, Ltd.
Advanced measurement of surface charge distribution with high potential
Authors: Kumada Akiko , Wangcen Qin , Hidaka Kunihiko
Published: December 2012

A measuring technique with a multilayer insulator is proposed to enable charge distribution measurement on an insulator of high potential. By using this technique, the residual charge distribution of the positive surface discharge was successfully measured with an electrostatic probe; nevertheless its potential is 10 times higher than the measurable range of an electrostatic probe. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Imputation
Authors: Rässler Susanne , Rubin Donald B. , Zell Elizabeth R.
Published: December 2012

Missing data are a common problem in statistics. Imputation, or filling in the missing values, is an intuitive and flexible way to address the resulting incomplete data sets. We focus on multiple imputation, which, when implemented correctly, can be a statistically valid strategy for handling missing data. The analysis of a multiply‐imputed data set is now relatively standard using readily available statistical software. The creation of multiply‐imputed data sets is more challenging than their analysis but still straightforward relative to other valid methods of handling missing data, and we discuss available software for doing so.Ad hocmethods, including using singly‐imputed data sets, almost always lead to invalid inferences and should be eschewed, especially when valid interval estimation or hypothesis testing is the objective.WIREs Comput Stat2013, 5:20–29. doi: 10.1002/wics.1240

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Data Reduction, Smoothing, and Filtering

Statistical and Graphical Methods of Data Analysis > Sampling
A Comparative Study of Consumer and B2B Goods Importers’ Trust and Commitment: Evidence from an Asian Developing Country
Authors: Saleh M. Abu , Ali M. Yunus , Quazi Ali
Published: December 2012

This paper develops and empirically tests a theoretical model integrating the predictors and consequences of relationship trust and commitment behaviour concerning consumer and B2B goods importers in an Asian developing market setting. A sample of 93 B2B and 139 consumer goods importers is used to test the model employing structural equation modelling. The results provide clear evidence that transaction-specific investment, environmental volatility and communication have varying impacts on trust and commitment and thus affecting international buyers’ relationships and their international exchange operations. The findings broaden and deepen our understanding of how consumer and B2B goods international exchange partners’ varying relationship outcomes can help reinforce their international relationships with foreign suppliers. These findings have strategic implications for maintaining effective relationships between B2B and consumer goods importers which are highlighted in this paper.
Global standardization measurement of cerebral spinal fluid for Alzheimer's disease: An update from the Alzheimer's Association Global Biomarkers Consortium
Authors: Carrillo Maria C. , Blennow Kaj , Soares Holly , Lewczuk Piotr , Mattsson Niklas , Oberoi Pankaj , Umek Robert , Vandijck Manu , Salamone Salvatore , Bittner Tobias , Shaw Leslie M. , Stephenson Diane , Bain Lisa , Zetterberg Henrik
Published: December 2012

Recognizing that international collaboration is critical for the acceleration of biomarker standardization efforts and the efficient development of improved diagnosis and therapy, the Alzheimer's Association created the Global Biomarkers Standardization Consortium (GBSC) in 2010. The consortium brings together representatives of academic centers, industry, and the regulatory community with the common goal of developing internationally accepted common reference standards and reference methods for the assessment of cerebrospinal fluid (CSF) amyloid β42 (Aβ42) and tau biomarkers. Such standards are essential to ensure that analytical measurements are reproducible and consistent across multiple laboratories and across multiple kit manufacturers. Analytical harmonization for CSF Aβ42 and tau will help reduce confusion in the AD community regarding the absolute values associated with the clinical interpretation of CSF biomarker results and enable worldwide comparison of CSF biomarker results across AD clinical studies.
A Rare Cause of Compression Neuropathy of Upper Limbs - Ganglionic Cysts
Authors: Wai-Yin Mak
Published: December 2012

We report a 51-year-old Chinese male with a ganglion in the Guyon canal causing ulnar nerve palsy and a 54-year-old Chinese male with a ganglion in the elbow causing posterior interosseous nerve (PIN) palsy. Exploration and excision of the ganglions were performed. Both patients made a good recovery.
RETRACTED: Inosine‐specific cleavage of RNA for microarray analysis of RNA A‐to‐I editing targets
Authors: Huang Hurng‐Wern , Chang Hsueh‐Wei , Wang Hui‐Chun , Lu Chiu‐Jin , Chen Shaio‐Wen , Yi Szu‐Cheng , Wang Hay‐Yan , Cho Chung‐Lung , Wu Cheng‐Hsuan , Yang Jyuer‐Ger , Tseng Chao‐Neng
Published: December 2012

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).

This article has been retracted at the request of the Editor.

It has come to our attention that there is substantial duplication of some figures between this Kaohsiung Journal of Medical Science article and an earlier paper by the same authors, Chao‐Neng Tseng et al, A method to identify RNA A‐to‐I editing targets using I‐specific cleavage and exon array analysis, Molecular and Cellular Probes, Vol 27, 38‐45 (2013), https://doi.org/10.1016/j.mcp.2012.08.008.

One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re‐use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
A REVIEW OF HEALTH TECHNOLOGY APPRAISALS: CASE STUDIES IN ONCOLOGY
Authors: Shah Koonal Kirit , Mestre-Ferrandiz Jorge , Towse Adrian , Smyth Emily Nash
Published: December 2012

Pharmaceutical manufacturers, regulators, patients, providers, and payers all have a shared interest in improving health outcomes for patients with cancer. Each plays an important role in helping to achieve this common goal. Pharmaceutical manufacturers seek to develop new medicines that are supported by robust and clinically meaningful evidence of their safety, efficacy, and effectiveness. Regulators authorize these medicines based on evaluations of their safety and efficacy. Patients and providers together make treatment decisions and desire access to the most effective treatment options. Payers appraise new medicines with the goal of ensuring access to those medicines that constitute efficient uses of healthcare expenditure. Profits generated from the sale of the medicines provide a return to the manufacturer, which helps to drive continued research and development in an effort to improve patient health outcomes and societal well-being. Many payers have initiated health technology assessment (HTA) activities to inform decision making in light of the rising costs of health care. Given the financial constraints imposed as a result of the global economic crisis, HTAs are likely to become increasingly important as payers seek value for money solutions to major health problems. Successful collaboration and aligning incentives across stakeholders is critical to ensuring that patients are able to access the most effective medicines.
BENEFITS OF CONTINUOUS SUBCUTANEOUS INSULIN INFUSION ON QUALITY OF LIFE
Authors: Lukács Andrea , Kiss-Tóth Emőke , Varga Beatrix , Soós Andrea , Takác Peter , Barkai László
Published: December 2012

Purpose: The aim of this study was to compare the general health-related quality of life (HRQoL), the metabolic control (HbA1c), the anthropometric measurement, and the cardiorespiratory fitness (expressed by VO2max) in youths with type 1 diabetes treated with continuous subcutaneous insulin infusion (CSII) to those receiving multiple daily injections (MDI). We looked for factors influencing the HRQoL and metabolic control.

Methods: A total of 239 patients treated with CSII (51 girls and 53 boys) or MDI (64 girls and 71 boys) between ages 8 and 18 years were assessed with the Pediatric Quality of Life Inventory, Generic Core Scales, and Diabetes Module. VO2max was evaluated using the 20-meter shuttle run test.

Results: CSII group had significantly better HRQoL according to both child self-report and parent proxy-report. Youths with CSII reported better physical, emotional, and school-related functioning, and had less diabetes-related fear and symptoms than the MDI group. There were no significant differences in body mass index z-scores, insulin doses, HbA1c, and VO2max between the groups. HRQoL was predicted by the CSII therapy (β = −0.220; p = .000) and the VO2max (β = 0.386; p = .000), other clinical and anthropometric parameters had no effect; the HbA1c was predicted only by VO2max (β = −0.353; p = .000).

Conclusions: Diabetic youths treated with CSII therapy have better HRQoL than those treated with MDI. There are no differences between the investigated groups in anthropometric data, glycated hemoglobin, and physical fitness. Moreover, good physical fitness has an important role in achieving better metabolic control and HRQoL, which underlines the importance of regular aerobic exercise in the treatment and care of type 1 diabetes in childhood.
Nachrichten
Authors: Weber Heike
Published: December 2012

PD Dr. Sabine Vollstädt-Klein: Initial, habitual and compulsive alcohol use is characterized by a shift of cue processing from ventral to dorsal striatum. Addiction, 105, 1741–1749.

Zu Beginn der Entwicklung einer Substanzabhängigkeit stehen hedonische Effekte des Substanzkonsums im Vordergrund, während im späteren Verlauf eher gewohnheitsmäßig oder gar zwanghaft konsumiert wird. Tierstudien konnten zeigen, dass diese Veränderungen mit einem Übergang von präfrontaler kortikaler Kontrolle durch striatale Kontolle einhergehen und außerdem Reizverarbeitungsprozesse sich innerhalb des Striatums von ventral nach dorsal verlagern. Beim Menschen gab es bisher noch keine Untersuchungen zu diesem Thema.

In dieser Studie wurde mittels funktioneller Magnetresonanztomographie (fMRT) die neuronale Reizreaktion auf alkoholassoziierte visuelle Stimuli bei 21 schweren Trinkern ohne Behandlungswunsch (darunter 13 mit Alkoholabhängigkeit) und 10 leichten sozialen Trinkern als gesunde Kontrollen untersucht. Außerdem wurde mittels eines Fragebogens das Ausmaß zwanghafter Gedanken und Handlungen im Zusammenhang mit Alkohol erfasst.

Die vorliegende Studie konnte die beschriebenen präklinischen Befunde bestätigen. Schwere Trinker aktivierten in Reaktion auf Alkoholreize eher das dorsale Striatum, während sich bei den Kontrollen mehr Aktivierung im ventralen Striatum und in präfrontalen Arealen zeigte. Dazu passend zeigte sich im ventralen Striatum eine Abnahme der Reizreaktion mit zwanghaftem Alkoholverlangen, während die Aktivierung im dorsalen Striatum mit stärkerem zwanghaftem Alkoholverlangen zunahm.

Die Ergebnisse der Studie sind unter verschiedenen Aspekten als klinisch bedeutsam zu betrachten. Die vorliegenden Daten könnten erklären, warum Medikamente, welche die belohnenden Effekte von Alkohol reduzieren (wie beispielsweise Naltrexon) nur in Subgruppen alkoholabhängiger Patienten wirken. Diese Medikamente könnten vor allem bei nicht-abhängigen schweren Trinkern oder bei Alkoholabhängigen in früheren Stadien wirksam sein, da bei diesen Individuen noch die hedonischen Effekte des Alkohols, repräsentiert durch eine reizinduzierte Aktivierung im ventralen Striatum, im Vordergrund zu stehen scheinen. Frühere Studien zeigten, dass reizinduzierte Hirnaktivierung mit Rückfall assoziiert zu sein scheint. Daher könnte die fMRT-Reizreaktion zum Therapiemonitoring geeigneter sein als beispielsweise Fragebögen zum Alkoholverlangen, da Patienten oft sozial erwünscht antworten.
Performance of recent and high-performance approximate density functionals for time-dependent density functional theory calculations of valence and Rydberg electronic transition energies
Authors: Isegawa Miho , Peverati Roberto , Truhlar Donald G.
Published: December 2012

We report a test of 30 density functionals, including several recent ones, for their predictions of 69 singlet-to-singlet excitation energies of 11 molecules. The reference values are experimental results collected by Caricato et al. for 30 valence excitations and 39 Rydberg excitations. All calculations employ time-dependent density functional theory in the adiabatic, linear-response approximation. As far as reasonable, all of the assignments are performed by essentially the same protocol as used by Caricato et al., and this allows us to merge our mean unsigned errors (MUEs) with the ones they calculated for both density functional and wave function methods. We find 21 of the 30 density functionals calculated here have smaller MUEs for the 30 valence states than what they obtained (0.47 eV) for the state-of-the-art EOM-CCSD wave function. In contrast, for all of density functionals the MUE for 39 Rydberg states is larger than that (0.11 eV) of EOM-CCSD. Merging the 30 density functionals calculated here with the 26 calculated by Caricato et al. makes a set of 56 density functionals. Averaging the unsigned errors over both the valence excitations and the Rydberg excitations, none of the 56 density functionals shows a lower mean unsigned error than that (0.27 eV) of EOM-CCSD. Nevertheless, two functionals are successful in having an overall mean unsigned error of 0.30 eV, and another nine are moderately successful in having overall mean unsigned errors in the range 0.32–0.36 eV. Successful or moderately successful density functionals include seven hybrid density functionals with 41% to 54% Hartree–Fock exchange, and four range-separated hybrid density functionals in which the percentage of Hartree–Fock exchange increases from 0% to 19% at small interelectronic separation to 65%–100% at long range.
Electron paramagnetic resonance probed oxygen deficiency in SrTiO3 with different cap layers
Authors: Chen Y. S. , Guo H. Y. , Chi Yang Jan , Chu Y. H. , Wu W. F. , Lin J. G.
Published: December 2012

The oxygen vacancies in the SrTiO3 (STO) single crystal with two different cap layers, CoFe2O4 (CFO) and BiFeO3 (BFO), are investigated with the technique of electron paramagnetic resonance (EPR). EPR spectra show the resonance lines of the residual oxygen vacancy in air annealed STO, STO/CFO, and STO/BFO, showing the high sensitivity of EPR to the low concentration defects. The experimental results indicate that the oxide cap layers enhance the oxygen deficiency in bulk STO and the amount of oxygen vacancy is dependent on the electronegativity of metal ion in the cap layer. Accordingly, STO/BFO has a larger amount of oxygen vacancy than that of STO/CFO.
Raman microscopy of silicon for electronic displays and solar cells: Enhanced Raman scattering observed for microstructured surface
Authors: Kitahara K. , Ishizaki A.
Published: December 2012

This paper describes Raman spectroscopy of microstructured silicon (Si), which is used for electronic displays, solar cells, and other applications. Enhanced Raman scattering was found for excimer laser crystallized polycrystalline Si (ELC poly-Si) thin films, texture-structured Si, black Si, and porous Si. Raman scattering of those materials reflects mainly the conditions at projections on their surfaces. Atomic force microscopy and Raman spectroscopy for ELC poly-Si indicated that hillocks and ridges are located at grain boundaries where the defect density is relatively large and the thermal stress in the films is somewhat relaxed. The enhancement effect was shown to be useful for detecting a local vibration mode that could not be easily detected for mirror-finished Si. The variation in the enhancement ratio with the incident light wavelength was examined for comparison with the electromagnetic model.
Calorimeters for precision power dissipation measurements on controlled-temperature superconducting radiofrequency samples
Authors: Xiao B. P. , Reece C. E. , Phillips H. L. , Kelley M. J.
Published: December 2012

Two calorimeters, with stainless steel and Cu as the thermal path material for high precision and high power versions, respectively, have been designed and commissioned for the 7.5 GHz surface impedance characterization system at Jefferson Lab to provide low temperature control and measurement for CW power up to 22 W on a 5 cm diameter disk sample which is thermally isolated from the radiofrequency (RF) portion of the system. A power compensation method has been developed to measure the RF induced power on the sample. Simulation and experimental results show that with these two calorimeters, the whole thermal range of interest for superconducting radiofrequency materials has been covered. The power measurement error in the interested power range is within 1.2% and 2.7% for the high precision and high power versions, respectively. Temperature distributions on the sample surface for both versions have been simulated and the accuracy of sample temperature measurements have been analyzed. Both versions have the ability to accept bulk superconductors and thin film superconducting samples with a variety of substrate materials such as Al, Al2O3, Cu, MgO, Nb, and Si.
Activation and thermal stability of ultra-shallow B+-implants in Ge
Authors: Yates B. R. , Darby B. L. , Petersen D. H. , Hansen O. , Lin R. , Nielsen P. F. , Romano L. , Doyle B. L. , Kontos A. , Jones K. S.
Published: December 2012

The activation and thermal stability of ultra-shallow B+ implants in crystalline (c-Ge) and preamorphized Ge (PA-Ge) following rapid thermal annealing was investigated using micro Hall effect and ion beam analysis techniques. The residual implanted dose of ultra-shallow B+ implants in Ge was characterized using elastic recoil detection and was determined to correlate well with simulations with a dose loss of 23.2%, 21.4%, and 17.6% due to ion backscattering for 2, 4, and 6 keV implants in Ge, respectively. The electrical activation of ultra-shallow B+ implants at 2, 4, and 6 keV to fluences ranging from 5.0 × 1013 to 5.0 × 1015 cm−2 was studied using micro Hall effect measurements after annealing at 400–600 °C for 60 s. For both c-Ge and PA-Ge, a large fraction of the implanted dose is rendered inactive due to the formation of a presumable B-Ge cluster. The B lattice location in samples annealed at 400 °C for 60 s was characterized by channeling analysis with a 650 keV H+ beam by utilizing the 11B(p, α)2α nuclear reaction and confirmed the large fraction of off-lattice B for both c-Ge and PA-Ge. Within the investigated annealing range, no significant change in activation was observed. An increase in the fraction of activated dopant was observed with increasing energy which suggests that the surface proximity and the local point defect environment has a strong impact on B activation in Ge. The results suggest the presence of an inactive B-Ge cluster for ultra-shallow implants in both c-Ge and PA-Ge that remains stable upon annealing for temperatures up to 600 °C.
Magnetoresistance and shot noise in graphene-based nanostructure with effective exchange field
Authors: Liu Zheng-Fang , Liu Nian-Hua , Wu Qing-Ping
Published: December 2012

Based on the transfer-matrix method, we investigated the spin transport through a graphene-based nanostructure with effective exchange field. It is found that the effective exchange field induces a spin-dependent Klein tunneling. The magnetoresistance becomes a number of times larger than that in the case of the Rashba spin-orbit interaction. With increasing the effective exchange field strength, the magnetoresistance and the Fano factor exhibit periodic oscillation features. In graphene superlattice, when the effective exchange field satisfies a certain condition, the Fano factor can be tuned from nearly zero to 1/3 by applying an appropriate periodic gate voltage.
A two-dimensional Wigner crystal (Review Article)
Authors: Monarkha Yu. P. , Syvokon V. E.
Published: December 2012

The current state of theoretical and experimental studies of the Wigner crystallization of a two-dimensional electron gas is reviewed. The Wigner crystal (WC) has first been observed experimentally in a two-dimensional electron system on the surface of liquid helium in 1979. This success was favored by the exceptional purity of the free surface of superfluid liquid and the ability to fairly accurately describe the polaronic deformation phenomena accompanying the crystallization of electrons. Very pure samples of heterostructures (GaAs/GaAlAs) and strong magnetic fields, making easier the localization of electrons in a conducting layer, were necessary in order to observe the Wigner crystallization in semiconductor two-dimensional electron systems This review discusses the basic properties of a two-dimensional WC, common to the both above-mentioned electronic systems, and also major advances in the study of transport properties of WC caused by response of the environment on motion of the electron lattice.
The effect of confining potential on the stability of an electron crystal over liquid helium
Authors: Slavin V. V. , Krivchikov A. A.
Published: December 2012

A mechanism of destabilization of an electron crystal over liquid helium is described in the case when the confining electric field is below the field required for complete charge compensation. The dependence of the electron crystal stability parameter on the external confining electric field is obtained within the framework of a one-electron model and in the quasi-classical approximation. It is shown that for an arbitrarily small “undercompensation” of the external electric field the electrons evaporate from the helium surface via both thermal activation and tunneling. The contribution of the tunneling process increases rapidly with electron concentration. The experimental data on the electric properties of the electron crystal over helium surface have been explained using the proposed model.
The structural, electronic and magnetic properties of iron nanowires with different diameters
Authors: Boutko V. G. , Gusev A. A. , Shevtsova T. N. , Pashkevich Yu. G.
Published: December 2012

The electronic structure of iron nanowires with transverse dimensions up to 9 Å was calculated using the density functional theory methods. The calculations were carried out taking into account not only the transverse but also the longitudinal optimization of the structural parameters of nanowires. It was shown that the magnetic moments of Fe atoms, on average, decrease with increasing the transverse dimensions of the nanowires and increase with the distance from the nanowire axis. Giant magnetic anisotropy energy was obtained for Fe1 and Fe9 structures.
Investigation of ferroelectric phase transition for barium strontium titanate ceramics by in situ Raman scattering
Authors: Zhang Qiwei , Zhai Jiwei , Kong Lingbing , Yao Xi
Published: December 2012

The origin of the change in ferroelectric properties of Ba0.6Sr0.4TiO3 (BST60) ceramics near Curie temperature due to the application of an electric field was investigated by using Raman scattering spectroscopy. The results showed that different structural responses were induced upon electric fields (E). The relative intensity ratio between the vibrating modes of A1(TO3) and E(TO4) was attributed to the structural phase transitions induced by the electric field E. The increase in degree of structural distortion with increasing E was in a good agreement with the gradual shift in Curie point to higher temperature. These electric-field-induced structural effects contributed significantly to the tunability of the BST60 ceramics. These conclusion should be also applicable to other ferroelectric materials.
A model for phosphosilicate glass deposition via POCl3 for control of phosphorus dose in Si
Authors: Chen Renyu , Wagner Hannes , Dastgheib-Shirazi Amir , Kessler Michael , Zhu Zihua , Shutthanandan Vaithiyalingam , Altermatt Pietro P. , Dunham Scott T.
Published: December 2012

Effective control of the dose of diffused phosphorus emitter profiles is crucial for optimization of crystalline silicon solar cells, but it requires detailed understanding of the POCl3 doping process. We measure concentration profiles within the deposited phosphosilicate glass (PSG) layer for a range of POCl3 doping conditions and find that (i) its composition is nearly independent of process conditions and (ii) it is separated from Si by a thin SiO2 layer. We also find strong accumulation of P at the SiO2-Si interface. As common linear-parabolic models cannot fully explain the observed kinetics of PSG thickness and phosphorus dose in Si, we present an improved model including oxygen depletion and dose saturation, giving a better explanation of the experimental data. In contrast to previous models that adjust the peak phosphorus concentration at the Si surface to match the measured profiles, our models accurately predict the time-dependent dose behavior under different experimental conditions. We further couple this growth model with previously reported phosphorus diffusion and deactivation models in silicon, providing full modeling of the POCl3 doping process.
Shock model description of the interaction radiation pulse in nested wire array z-pinches
Authors: Ampleford D. J. , Jennings C. A. , Lebedev S. V. , Bland S. N. , Cuneo M. E. , Sinars D. B. , Bott S. C. , Hall G. N. , Suzuki-Vidal F. , Palmer J. B. A. , Chittenden J. P.
Published: December 2012

Bow shock structures are observed in a nested wire array z-pinch as ablation streams from the outer array pass the inner array. The jump in plasma conditions across these shocks results in an enhancement of snowplow emission from the imploding plasma piston. Results from a snowplow model modified to account for the shock jumps are discussed and compared to experimental data from MAGPIE. Magnetohydrodynamic simulations indicate that this is the primary heating mechanism responsible for the interaction pulse recorded on the Z generator, which is required for pulse shaping for inertial confinement fusion.
Polarity-controlled ultraviolet/visible light ZnO nanorods/p-Si photodetector
Authors: Xie Yong , Madel Manfred , Li Yujie , Jie Wanqi , Neuschl Benjamin , Feneberg Martin , Thonke Klaus
Published: December 2012

Vertically aligned ZnO nanorods of high quality were grown on p-type silicon substrate by a modified chemical vapor phase process. Low temperature photoluminescence measurements show a near band gap donor bound exciton full width at half maximum of less than 500 μeV, and only weak green defect luminescence proofing the superior optical quality of the ZnO structures. n-ZnO/p-Si photodetector devices were processed from these upright standing nanorods. The devices show bias dependent selective photon response: under forward bias, an ultraviolet to visible sensitivity ratio of three orders of magnitude was achieved, while under reverse bias ultraviolet and visible light contributed similarly to the electrical readout current. Thus, the characteristics of this detector element can be switched between “solar blind” and “broadband.”
Spectroscopic imaging ellipsometry and Fano resonance modeling of graphene
Authors: Matković Aleksandar , Beltaos Angela , Milićević Marijana , Ralević Uroš , Vasić Borislav , Jovanović Djordje , Gajić Radoš
Published: December 2012

In this work, we have examined the optical properties of exfoliated graphene on an Si/SiO2 substrate using spectroscopic imaging ellipsometry in the visible range (360–800 nm). Measured spectra were analyzed by an optical model based on the Fresnel coefficient equations. The optical model was supported by correlated Raman and atomic force microscopy measurements. The complex refractive index of graphene was obtained by inversion of the measured ellipsometry data. The Fano line-shape was used to parameterize the optical properties. Measurements were highly reliable due to the numerous advantages of the spectroscopic imaging ellipsometric technique combined with the proper choice of substrate and experimental set-up. Thickness maps of the graphene sample were obtained from spatially resolved imaging ellipsometry spectra with a spot size of 1 μm. The data showed the presence of a water layer on the surface of the sample, and the thickness was mapped showing the distribution of water over graphene in ambient conditions.
Doppler-shifted optical absorption characterization of plume-lateral expansion in laser ablation of a cerium target
Authors: Miyabe M. , Oba M. , Iimura H. , Akaoka K. , Maruyama Y. , Ohba H. , Tampo M. , Wakaida I.
Published: December 2012

The temporal evolution of the ablation plume of cerium was investigated by absorption spectroscopy. Cerium oxide pellets were ablated in a helium atmosphere by second-harmonic radiation (532 nm) from a Nd:YAG laser at a fluence of 0.5 J/cm2. The lateral velocity (expansion velocity horizontal to the sample surface) of the plume was determined from the magnitude of the Doppler splitting of the absorption spectra measured close to the sample surface. The lateral velocities of neutral and singly ionized atoms were systematically investigated by varying several parameters, such as ambient gas pressure, ablation laser fluence, observation timing, and observation height. In addition, temporal profiles of the absorption signal were measured by detuning the probe laser frequency from the atomic resonant frequency in order to obtain the temporal variation of the velocity. On the basis of the drag force model, the slowing coefficients for atomic and ionic species in a helium atmosphere were evaluated along with lateral velocity in a vacuum. This study may help in understanding the plume dynamics effect on deposited film properties as well as optimizing experimental conditions for ablation-based spectroscopic analysis.