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Kinds of Nd Terms modified by Nd Selected AbstractsSafety of sertindole versus risperidone in schizophrenia: principal results of the sertindole cohort prospective study (SCoP)ACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2010S. H. L. Thomas Thomas SHL, Drici MD, Hall GC, Crocq MA, Everitt B, Lader MH, Le Jeunne C, Naber D, Priori S, Sturkenboom M, Thibaut F, Peuskens J, Mittoux A, Tanghøj P, Toumi M, Moore ND, Mann RD. Safety of sertindole versus risperidone in schizophrenia: principal results of the sertindole cohort prospective study (SCoP) Objective:, To explore whether sertindole increases all-cause mortality or cardiac events requiring hospitalization, compared with risperidone. Method:, Multinational randomized, open-label, parallel-group study, with blinded classification of outcomes, in 9858 patients with schizophrenia. Results:, After 14147 person-years, there was no effect of treatment on overall mortality (sertindole 64, risperidone 61 deaths, Hazard Ratio (HR) = 1.12 (90% CI: 0.83, 1.50)) or cardiac events requiring hospitalization [sertindole 10, risperidone 6, HR = 1.73 (95% CI: 0.63, 4.78)]: Of these, four were considered arrhythmia-related (three sertindole, one risperidone). Cardiac mortality was higher with sertindole (Independent Safety Committee (ISC): 31 vs. 12, HR=2.84 (95% CI: 1.45, 5.55), P = 0.0022; Investigators 17 vs. 8, HR=2.13 (95% CI: 0.91, 4.98), P = 0.081). There was no significant difference in completed suicide, but fewer sertindole recipients attempted suicide (ISC: 68 vs. 78, HR=0.93 (95% CI: 0.66, 1.29), P = 0.65; Investigators: 43 vs. 65, HR=0.67 (95% CI: 0.45, 0.99), P = 0.044). Conclusion:, Sertindole did not increase all-cause mortality, but cardiac mortality was higher and suicide attempts may be lower with sertindole. [source] An update on the role of glutamate in the pathophysiology of depressionACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010N. D. Mitchell Mitchell ND, Baker GB. An update on the role of glutamate in the pathophysiology of depression. Objective:, To review the literature on the involvement of glutamate (Glu), including its interactions with other neurochemical systems, in the pathophysiology of depression. Method:, A MEDLINE search using the terms glutamate, depression and major depressive disorder, was performed. Results:, Alterations in proteins involved in glutamatergic signalling are implicated in variations in behaviour in animal models of depression. Drugs acting at Glu receptors appear to have antidepressant-like effects in these models, and traditional antidepressant pharmacotherapies act on the glutamatergic system. Recent evidence from genetic studies and in vivo spectroscopy also correlate glutamatergic dysfunction with depression. Trials of N -methyl- d -aspartate receptor antagonists in humans have provided mixed results. Conclusion:, A growing body of evidence indicates that the glutamatergic system is involved in the pathophysiology of depression, and may represent a target for intervention. [source] Estimation of temporal variation in splash detachment in two Japanese cypress plantations of contrasting ageEARTH SURFACE PROCESSES AND LANDFORMS, Issue 9 2010Y. Wakiyama Abstract To elucidate splash erosion processes under natural rainfall conditions, temporal variations in splash detachment were observed using a piezoelectric saltation sensor (H11B; Sensit Co., Portland, ND, USA). Preliminary laboratory tests of Sensit suggested that they were suitable for field observations. Field observations were conducted between July and September 2006 in 21- and 36-year-old Japanese cypress (Chamaecyparis obtusa) plantations with mean stand heights of 9·2,m and 17·4,m, respectively. Splash detachment (in g m,2) was measured seven times using splash cups, and raindrop kinetic energy (in J,m,2,mm,1) in both stands was measured using laser drop-sizing (LD) gauges. Sensit was installed to record saltation counts, which were converted to temporal data of splash detachment (splash rate; in g m,2 10,min,1) using the relationship between splash detachment and saltation counts. Surface runoff was monitored using runoff plots of 0·5,m width and 2·0,m length to obtain temporal data of flow depth (in millimeters). Both total splash detachment and raindrop kinetic energy were larger in the older stand. Increased splash rates per unit throughfall were found in both stands after rainless durations longer than approximately one day in both stands. However, a lower splash rate was found in the 21-year stand after rainfall events. During extreme rainstorms, the 21-year stand showed a low runoff rate and a decline in the splash rate, while the 36-year stand showed a higher splash rate and increased flow depth. The piezoelectric sensor proved to be a useful means to elucidate splash erosion processes in field conditions. Copyright © 2010 John Wiley & Sons, Ltd. [source] Sequencing of DSM-IV criteria of nicotine dependenceADDICTION, Issue 8 2009Denise B. Kandel ABSTRACT Aims To determine whether there is a sequence in which adolescents experience symptoms of nicotine dependence (ND) as per the DSM-IV. Design A two-stage design was implemented to select a multi-ethnic target sample of adolescents from a school survey of 6th,10th graders from the Chicago Public Schools. The cohort was interviewed at home five times with structured computerized interviews at 6-month intervals over a 2-year period. Participants Subsample of new tobacco users (n = 353) who had started to use tobacco within 12 months prior to wave 1 or between waves 1 and 5. Measurements and statistical methods Monthly histories of DSM-IV symptoms of ND were obtained. Log-linear quasi-independence models were estimated to identify the fit of different cumulative models of progression among the four most prevalent dependence criteria (tolerance, impaired control, withdrawal, unsuccessful attempts to quit), indexed by specific symptoms, by gender and race/ethnicity. Findings Pathways varied slightly across groups. The proportions who could be classified in a progression pathway not by chance ranged from 50.7% to 68.8%. Overall, tolerance and impaired control appeared first and preceded withdrawal; impaired control preceded attempts to quit. For males, tolerance was experienced first, with withdrawal a minor path of entry; for females withdrawal was experienced last, tolerance and impaired control were experienced first. For African Americans, tolerance by itself was experienced first; for other groups an alternative path began with impaired control. Conclusions The prevalence and sequence of criteria of ND fit our understanding of the neuropharmacology of ND. The order among symptoms early in the process of dependence may differ from the severity order of symptoms among those who persist in smoking. [source] Contaminant pattern and bioaccumulation of legacy and emerging organhalogen pollutants in the aquatic biota from an e-waste recycling region in South ChinaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2010Ying Zhang Abstract Legacy pollutants, polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), and some emerging organhalogen pollutants, such as polybrominated diphenyl ethers (PBDEs), hexabromobenzene (HBB), pentabromotoluene (PBT), 2,3,4,5,6-pentabromoethyl benzene (PBEB), 1,2- bis (2,4,6-tribromophenoxy) ethane (BTBPE), and dechlorane plus (DP), were detected in an aquatic food chain (invertebrates and fish) from an e-waste recycling region in South China. Polychlorinated biphenyls, DDTs, PBDEs, and HBB were detected in more than 90% of the samples, with respective concentrations ranging from not detected (ND),32,000,ng/g lipid weight, ND,850,ng/g lipid weight, 8 to 1,300,ng/g lipid weight, and 0.28 to 240,ng/g lipid weight. Pentabromotoluene, PBEB, BTBPE, and DP were also quantifiable in collected samples with a concentration range of ND,40,ng/g lipid weight. The elevated levels of PCBs and PBDEs in the organisms, compared with those in non-e-waste regions in South China, suggest that these two kinds of pollutants derived mainly from e-waste recycling practices. Hexabromobenzene was significantly correlated with PBDEs, implying that HBB come from the release of e-waste along with PBDEs and/or the pyrolysis of BDE209. Most of the compounds whose trophic magnification factor (TMF) could be calculated were found to biomagnify (TMF > 1). Hexabromobenzene was also found, for the first time, to biomagnify in the present food web, with a TMF of 2.1. Environ. Toxicol. Chem. 2010;29:852,859. © 2010 SETAC [source] Variation in mitochondrial DNA control region haplotypes in populations of the bank vole, Clethrionomys glareolus, living in the Chernobyl environment, UkraineENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2006Jeffrey K. Wickliffe Abstract Bank vole, Clethrionomys glareolus, specimens have been annually sampled from the radioactive Chernobyl, Ukraine, environment and nonradioactive reference sites since 1997. Exposed voles continually exhibit increased mitochondrial DNA hap-lotype (h) and nucleotide diversity (ND), observed in the hypervariable control region (1997,1999). Increased maternal mutation rates, source,sink relationships, or both are proposed as hypotheses for these differences. Samples from additional years (2000 and 2001) have been incorporated into this temporal study. To evaluate the hypothesis that an increased mutation rate is associated with increased h, DNA sequences were examined in a phylogenetic context for novel substitutions not observed in haplotypes from bank voles from outside Ukraine or in other species of Clethrionomys. Such novel substitutions might result from in situ mutation events and, if largely restricted to samples from radioactive environments, support an increased maternal mutation rate in these areas. The only unique substitution meeting this criterion was found in an uncontaminated reference site. All other substitutions are found in other haplotypes of the bank vole or in other species. Increased maternal mutation rates do not appear to explain trends in h and ND observed in northern Ukraine. Studies examining ecological dynamics will clarify the reasons behind, and significance of, increased levels of h in contaminated areas. [source] Direct Cost of Medical Management of Epilepsy among Adults in Italy: A Prospective Cost-of-Illness Study (EPICOS)EPILEPSIA, Issue 2 2004Ettore Beghi Summary: Purpose: To investigate the costs of epilepsy from a nationwide survey comparing adult patients included in different prognostic categories. Methods: A 12-month prospective observational study was conducted in 15 epilepsy centers from Northern, Central, and Southern Italy. The study population included a random sample of individuals aged 18 years and older with newly diagnosed (ND) epilepsy, seizure remission (R), occasional seizures (OS), active non,drug-resistant (NDR) seizures, drug-resistant (DR) seizures, or surgical candidates (SC). Estimates of the direct costs of care of epilepsy were based on the use of diagnostic examinations, laboratory tests, specialist consultations, hospital admissions, day-hospital days, and drugs, taking the Italian National Health Service perspective. Results: The sample included 631 patients (ND 62, R 158, OS 155, NDR 114, DR 128, and SC 14). The SC group had the highest total cost per patient (,3,619) followed by DR (,2,190), ND (,976), NDR (,894), OS (,830), and R (,561). For each epilepsy group, the main components of the total cost were drugs and hospital admissions. Drug costs increased from the R group to the DR group. The new antiepileptic drugs (AEDs) were the largest part of the cost of treatment. Conclusions: The costs of epilepsy in referral patients vary significantly according to the time course of the disease and the response to treatment. Hospital admissions and drugs are the major sources of expenditure. [source] Inflammatory airway disease, nasal discharge and respiratory infections in young British racehorsesEQUINE VETERINARY JOURNAL, Issue 3 2005J. L. N. WOOD Summary Reasons for performing study: Respiratory disease is important in young Thoroughbred racehorses, but the variation in the rates of occurrence between different ages and training groups has not been characterised. Objectives: To determine the rates of respiratory disease, particularly inflammatory airway disease (IAD), as well as evidence of infection, and their variation between age and group. Methods: Horses were examined monthly in 7 British flat training yards over a 3 year period. IAD was defined as increased mucus in the trachea with increased proportions of neutrophils in tracheal wash samples. Frequencies of disease outcomes were estimated from the data. Results: The prevalence of IAD was 13.8% and the incidence was 8.9 cases/100 horses/month. Rates varied with training and age groups, decreasing in older animals. The prevalence of nasal discharge (ND) was 4.1%. Rates of bacterial isolation were more common than viral infections. The incidence and prevalence of several bacterial species decreased with age. Conclusions: IAD and ND were common in young racehorses, varying significantly between training groups and decreasing with age, consistent with infection playing a role in aetiology. Potential relevance: The high prevalence of IAD in 2-year-old horses in Britain suggests that routine endoscopic examination may be helpful in providing early diagnosis and appropriate therapy. The transmission of bacteria and viruses within and between groups of young animals and the role of infection, stable environment and factors inherent to each horse, including their genetic make-up, in the multifactorial aetiology of the disease all merit further study. [source] Discussion on ,Personality psychology as a truly behavioural science' by R. Michael FurrEUROPEAN JOURNAL OF PERSONALITY, Issue 5 2009Article first published online: 14 JUL 200 Yes We Can! A Plea for Direct Behavioural Observation in Personality Research MITJA D. BACK and BORIS EGLOFF Department of Psychology, Johannes Gutenberg University Mainz, Germany mback@uni-leipzig.de Furr's target paper (this issue) is thought to enhance the standing of personality psychology as a truly behavioural science. We wholeheartedly agree with this goal. In our comment we argue for more specific and ambitious requirements for behavioural personality research. Specifically, we show why behaviour should be observed directly. Moreover, we illustratively describe potentially interesting approaches in behavioural personality research: lens model analyses, the observation of multiple behaviours in diverse experimentally created situations and the observation of behaviour in real life. Copyright © 2009 John Wiley & Sons, Ltd. The Categories of Behaviour Should be Clearly Defined PETER BORKENAU Department of Psychology, Martin-Luther University Halle-Wittenberg, Germany p.borkenau@psych.uni-halle.de The target paper is helpful by clarifying the terminology as well as the strengths and weaknesses of several approaches to collect behavioural data. Insufficiently considered, however, is the clarity of the categories being used for the coding of behaviour. Evidence is reported showing that interjudge agreement for retrospective and even concurrent codings of behaviour does not execeed interjudge agreement for personality traits if the categories being used for the coding of behaviour are not clearly defined. By contrast, if the behaviour to be registered is unambiguously defined, interjudge agreement may be almost perfect. Copyright © 2009 John Wiley & Sons, Ltd. Behaviour Functions in Personality Psychology PHILIP J. CORR Department of Psychology, Faculty of Social Sciences, University of East Anglia, Norwich, UK Philip.Corr@btopenworld.com Furr's target paper highlights the importance, yet under-representation, of behaviour in published articles in personality psychology. Whilst agreeing with most of his points, I remain unclear as to how behaviour (as specifically defined by Furr) relates to other forms of psychological data (e.g. cognitive task performance). In addition, it is not clear how the functions of behaviour are to be decided: different behaviours may serve the same function; and identical behaviours may serve different functions. To clarify these points, methodological and theoretical aspects of Furr's proposal would benefit from delineation. Copyright © 2009 John Wiley & Sons, Ltd. On the Difference Between Experience-Sampling Self-Reports and Other Self-Reports WILLIAM FLEESON Department of Psychology, Wake Forest University, Winston-Salem, NC, USA fleesonW@wfu.edu Furr's fair but evaluative consideration of the strengths and weaknesses of behavioural assessment methods is a great service to the field. As part of his consideration, Furr makes a subtle and sophisticated distinction between different self-report methods. It is easy to dismiss all self-reports as poor measures, because some are poor. In contrast, Furr points out that the immediacy of the self-reports of behaviour in experience-sampling make experience-sampling one of the three strongest methods for assessing behaviour. This comment supports his conclusion, by arguing that ESM greatly diminishes one the three major problems afflicting self-reports,lack of knowledge,and because direct observations also suffer from the other two major problems afflicting self-reports. Copyright © 2009 John Wiley & Sons, Ltd. What and Where is ,Behaviour' in Personality Psychology? LAURA A. KING and JASON TRENT Department of Psychology, University of Missouri, Columbia, USA kingla@missouri.edu Furr is to be lauded for presenting a coherent and persuasive case for the lack of behavioural data in personality psychology. While agreeing wholeheartedly that personality psychology could benefit from greater inclusion of behavioural variables, here we question two aspects of Furr's analysis, first his definition of behaviour and second, his evidence that behaviour is under-appreciated in personality psychology. Copyright © 2009 John Wiley & Sons, Ltd. Naturalistic Observation of Daily Behaviour in Personality Psychology MATTHIAS R. MEHL Department of Psychology, University of Arizona, Tucson, AZ, USA mehl@email.arizona.edu This comment highlights naturalistic observation as a specific method within Furr's (this issue) cluster direct behavioural observation and discusses the Electronically Activated Recorder (EAR) as a naturalistic observation sampling method that can be used in relatively large, nomothetic studies. Naturalistic observation with a method such as the EAR can inform researchers' understanding of personality in its relationship to daily behaviour in two important ways. It can help calibrate personality effects against act-frequencies of real-world behaviour and provide ecological, behavioural personality criteria that are independent of self-report. Copyright © 2009 John Wiley & Sons, Ltd. Measuring Behaviour D. S. MOSKOWITZ and JENNIFER J. RUSSELL Department of Psychology, McGill University, Montreal, Canada dsm@psych.mcgill.ca Furr (this issue) provides an illuminating comparison of the strengths and weaknesses of various methods for assessing behaviour. In the selection of a method for assessing behaviour, there should be a careful analysis of the definition of the behaviour and the purpose of assessment. This commentary clarifies and expands upon some points concerning the suitability of experience sampling measures, referred to as Intensive Repeated Measurements in Naturalistic Settings (IRM-NS). IRM-NS measures are particularly useful for constructing measures of differing levels of specificity or generality, for providing individual difference measures which can be associated with multiple layers of contextual variables, and for providing measures capable of reflecting variability and distributional features of behaviour. Copyright © 2009 John Wiley & Sons, Ltd. Behaviours, Non-Behaviours and Self-Reports SAMPO V. PAUNONEN Department of Psychology, University of Western Ontario, London, Canada paunonen@uwo.ca Furr's (this issue) thoughtful analysis of the contemporary body of research in personality psychology has led him to two conclusions: our science does not do enough to study real, observable behaviours; and, when it does, too often it relies on ,weak' methods based on retrospective self-reports of behaviour. In reply, I note that many researchers are interested in going beyond the study of individual behaviours to the behaviour trends embodied in personality traits; and the self-report of behaviour, using well-validated personality questionnaires, is often the best measurement option. Copyright © 2009 John Wiley & Sons, Ltd. An Ethological Perspective on How to Define and Study Behaviour LARS PENKE Department of Psychology, The University of Edinburgh, Edinburgh, UK lars.penke@ed.ac.uk While Furr (this issue) makes many important contributions to the study of behaviour, his definition of behaviour is somewhat questionable and also lacks a broader theoretical frame. I provide some historical and theoretical background on the study of behaviour in psychology and biology, from which I conclude that a general definition of behaviour might be out of reach. However, psychological research can gain from adding a functional perspective on behaviour in the tradition of Tinbergens's four questions, which takes long-term outcomes and fitness consequences of behaviours into account. Copyright © 2009 John Wiley & Sons, Ltd. What is a Behaviour? MARCO PERUGINI Faculty of Psychology, University of Milan,Bicocca, Milan, Italy marco.perugini@unimib.it The target paper proposes an interesting framework to classify behaviour as well as a convincing plea to use it more often in personality research. However, besides some potential issues in the definition of what is a behaviour, the application of the proposed definition to specific cases is at times inconsistent. I argue that this is because Furr attempts to provide a theory-free definition yet he implicitly uses theoretical considerations when applying the definition to specific cases. Copyright © 2009 John Wiley & Sons, Ltd. Is Personality Really the Study of Behaviour? MICHAEL D. ROBINSON Department of Psychology, North Dakota State University, Fargo, ND, USA Michael.D.Robinson@ndsu.edu Furr (this issue) contends that behavioural studies of personality are particularly important, have been under-appreciated, and should be privileged in the future. The present commentary instead suggests that personality psychology has more value as an integrative science rather than one that narrowly pursues a behavioural agenda. Cognition, emotion, motivation, the self-concept and the structure of personality are important topics regardless of their possible links to behaviour. Indeed, the ultimate goal of personality psychology is to understanding individual difference functioning broadly considered rather than behaviour narrowly considered. Copyright © 2009 John Wiley & Sons, Ltd. Linking Personality and Behaviour Based on Theory MANFRED SCHMITT Department of Psychology, University of Koblenz-Landau, Landau, Germany schmittm@uni-landau.de My comments on Furr's (this issue) target paper ,Personality as a Truly Behavioural Science' are meant to complement his behavioural taxonomy and sharpen some of the presumptions and conclusions of his analysis. First, I argue that the relevance of behaviour for our field depends on how we define personality. Second, I propose that every taxonomy of behaviour should be grounded in theory. The quality of behavioural data does not only depend on the validity of the measures we use. It also depends on how well behavioural data reflect theoretical assumptions on the causal factors and mechanisms that shape behaviour. Third, I suggest that the quality of personality theories, personality research and behavioural data will profit from ideas about the psychological processes and mechanisms that link personality and behaviour. Copyright © 2009 John Wiley & Sons, Ltd. The Apparent Objectivity of Behaviour is Illusory RYNE A. SHERMAN, CHRISTOPHER S. NAVE and DAVID C. FUNDER Department of Psychology, University of California, Riverside, CA, USA funder@ucr.edu It is often presumed that objective measures of behaviour (e.g. counts of the number of smiles) are more scientific than more subjective measures of behaviour (e.g. ratings of the degree to which a person behaved in a cheerful manner). We contend that the apparent objectivity of any behavioural measure is illusory. First, the reliability of more subjective measures of behaviour is often strikingly similar to the reliabilities of so-called objective measures. Further, a growing body of literature suggests that subjective measures of behaviour provide more valid measures of psychological constructs of interest. Copyright © 2009 John Wiley & Sons, Ltd. Personality and Behaviour: A Neglected Opportunity? LIAD UZIEL and ROY F. BAUMEISTER Department of Psychology, Florida State University, Tallahassee, FL, USA Baumeister@psy.fsu.edu Personality psychology has neglected the study of behaviour. Furr's efforts to provide a stricter definition of behaviour will not solve the problem, although they may be helpful in other ways. His articulation of various research strategies for studying behaviour will be more helpful for enabling personality psychology to contribute important insights and principles about behaviour. The neglect of behaviour may have roots in how personality psychologists define the mission of their field, but expanding that mission to encompass behaviour would be a positive step. Copyright © 2009 John Wiley & Sons, Ltd. [source] Übersicht über die Sporenassoziationen (lepidophyta - bis pusilla -Zone) aus dem Unterkarbon der Bohrung Neuenkirchen 2/1973 (Insel Rügen, NE-Deutschland)FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 1 2001Gusti Burmann Abstract Es wird die Sporenzonierung für das Tournai (einschließlich der Grenzschichten) der Bohrung Neuenkirchen 2/73 auf der Insel Rügen (NE-Deutschland) vorgelegt - von der lepidophyta -Zone var. minor -Subzone des Tnla des obersten Devons bis zur pusilla -Zone des tieferen Visé. Das Profit wird verglichen mit der Zonenabfolge aus der Bohrung Wiek 4/70 (Burmann 1975). Zur lepidophyta -Zone liegen vergleichbare Daten aus dem Harz vor (Burmann 1976). Die untersuchte Abfolge von Sporenzonen umfasst die lepidophyta -Zone mit der var. minor -Subzone (höheres Tnla); PA (pusillites-asperitis; Tn1b); NRH (nitidus-rarituberculatus-hederatus; Tn1b-Tn2); ND (nitidus-distinctus; Tn2); RM (rarituber-culatus-minutissimus; tieferes Tn3); CM (claviger-macra; höheres Tn3); Pu (pusilla; V1a+V1b; Obergrenze der Pu-Zone nicht erfasst). Die stratigraphische Einbindung der Sporenzonen erfolgte durch makrofaunistische Datierungen. Die Pu-Zone ist in beiden Bohrungen untergliederbar durch einen Horizont mit Gloeocapsamorpha. Lower Carboniferous spore assemblages (lepidophyta zone to pusilla zone) in the Neuenkirchen 2/1973 borehole of Rügen Island, NE Germany A spore zonation is given for the Tournaisian sequence of the Neuenkirchen 2/73 borehole on the island of Rügen (NE Germany). The deposits range from the lepidophyta zone var. minor subzone of the uppermost Famennian (Tnla) to the pusilla zone of the basal Viséan. The results are compared with the miospore zonation of the borehole Wiek 4 (Burmann 1975), and comparable dates for the lepidophyta zone from the Harz mountains (Burmann 1976). In ascending order the miospore zones examined are: lepidophyta zone with var. minor subzone (upper part of Tnla); PA (pusillites-asperitis; Tnlb); NRH (nitidus-rarituberculatus-hederatus; Tnlb-Tn2): ND (nitidus-distinctus; Tn2); RM (rarituber-culatus-minutissimus; lower part of Tn3): CM (claviger-macra; upper part of Tn3); Pu (pusilla; V1a+V1b; the upper boundary of the Pu zone is not determined). The stratigraphy of the spore zones is also compared with the macrofaunal data. The Pu zone in both boreholes is divided into two parts by a horizon with Gloeocapsamorpha. [source] RhoA, encoding a Rho GTPase, is associated with smoking initiationGENES, BRAIN AND BEHAVIOR, Issue 8 2007X. Chen We used microarray analysis of acute nicotine responses in mouse brain to choose rationale candidates for human association studies on tobacco smoking and nicotine dependence (ND). Microarray studies on the time,course of acute response to nicotine in mouse brain identified 95 genes regulated in ventral tegmental area. Among these, 30 genes were part of a gene network, with functions relevant to neural plasticity. On this basis and their known roles in drug abuse or synaptic plasticity, we chose the genes RhoA and Ywhag as candidates for human association studies. A synteny search identified human orthologs and we investigated their role in tobacco smoking and ND in a human case,control association study. We genotyped five and three single nucleotide polymorphisms from the RhoA and Ywhag genes, respectively. Both single marker and haplotype analyses were negative for the Ywhag gene. For the RhoA gene, rs2878298 showed highly significant genotypic association with both smoking initiation (SI) and ND (P = 0.00005 for SI and P = 0.0007 for ND). In the allelic analyses, rs2878298 was only significant for SI. In the multimarker haplotype analyses, significant association with SI was found for the RhoA gene (empirical global P values ranged from 9 × 10,5 to 10,5). In all multimarker combinations analyzed, with or without inclusion of the single most significant marker rs2878298, identical risk and protective haplotypes were identified. Our results indicated that the RhoA gene is likely involved in initiation of tobacco smoking and ND. Replication and future model system studies will be needed to validate the role of RhoA gene in SI and ND. [source] The effect of temperature and daylength on heading in tetraploid cultivars of rhodesgrass (Chloris gayana Kunth)GRASSLAND SCIENCE, Issue 4 2005Isao Tarumoto Abstract The present study was conducted to clarify the effect of temperature and daylength on heading in tetraploid cultivars of rhodesgrass (Chloris gayana Kunth). Five cultivars, Tochiraku-kei (2,), Fords Katambora (2,), Callide (4,), Masaba (4,) and Pokot (4,), were planted on three dates at 1-month intervals (4 May, 4 June and 4 July) in three of the Ministry of Agriculture, Forestry and Fisheries research institutions in Ishigaki (Tropical Agriculture Research Center), Nishigoshi (Kyushu National Agricultural Experiment Station) and Nishinasuno (National Grassland Research Institute) in 1978. Three tetraploid cultivars were planted on three dates at 1-month intervals (4 May, 4 June and 4 July) under four daylength-treatments of natural daylength (ND), 12 h daylength [12 h], ND/12 h and 12 h/ND, and changed daylength at the eighth leaf stage, in Nishinasuno in 1978. Under natural daylength, although heading was not observed for Masaba and Pokot, heading was observed in all plots for Tochiraku-kei, Fords Katambora and Callide, and their days to heading (DH) linearly decreased with increases in daily mean temperature (DMT). The result indicated that, under natural daylength in summer, temperature was a major factor in determining DH in tetraploid Callide, which was the same as in diploid rhodesgrass cultivars. Callide reached heading under all four daylength treatments. However, Masaba and Pokot reached heading only under 12 h and ND/12 h treatments, suggesting that Masaba and Pokot have qualitative sensitivity to photoperiods that operate after the ninth leaf stage. These findings would be useful in tetraploid rhodesgrass for estimating foliage harvesting time in the field and for conducting cross-pollination in a greenhouse during winter. [source] Who merits a neck dissection after definitive chemoradiotherapy for N2,N3 squamous cell head and neck cancer?HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2003Scott A. McHam DO Abstract Background. The role of neck dissection (ND) after definitive chemoradiotherapy for squamous cell head and neck cancer is incompletely defined. We retrospectively reviewed 109 patients with N2,N3 disease treated with chemoradiotherapy to identify predictors of a clinical complete response in the neck (CCR-neck), pathologic complete response after ND (PCR-neck), and regional failure. Method. All patients were given 4-day continuous infusions of 5-fluorouracil (1000 mg/m2/d) and cisplatin (20 mg/m2/d) during the first and fourth weeks of either once daily (n = 68) or twice daily (n = 41) radiation therapy. ND was considered for all patients after completion of chemoradiotherapy and was performed in 32 of the 65 patients achieving a CCR-neck after chemoradiotherapy and in all 44 patients with residual clinical evidence of neck disease. CCR-neck, PCR-neck, and regional failure were then correlated with potential predictors, including T, N, largest lymph node size (<3 cm, ,3 cm), primary tumor site, and radiation fractionation schedule. Results. Achievement of a CCR-neck was predicted by N, N2 vs N3 (53 of 80 vs 12 of 29, p = .019) and by largest lymph node size, <3 cm vs ,3 cm (19 of 25 vs 46 of 84, p = .06). Achievement of a PCR-neck could not be predicted by any clinical parameter. Regional failure occurred both in patients undergoing ND and those not dissected (5 of 76 vs 4 of 33, p = .33) and proved more likely only in the ND patients with residual positive pathology compared with those achieving a PCR-neck (5 of 25 vs 0 of 51, p < .001). Primary site was not a useful predictor of CCR-neck, PCR-neck, or regional failure. Most importantly, CCR-neck (vs Grading of dysplasia in Barrett's oesophagus: substantial interobserver variation between general and gastrointestinal pathologistsHISTOPATHOLOGY, Issue 7 2007M Kerkhof Aims:, To determine interobserver variation in grading of dysplasia in Barrett's oesophagus (BO) between non-expert general pathologists and expert gastrointestinal pathologists on the one hand and between expert pathologists on the other hand. Methods and results:, In this prospective multicentre study, non-expert and expert pathologists graded biopsy specimens of 920 patients with endoscopic BO, which were blindly reviewed by one member of a panel of expert pathologists (panel experts) and by a second panel expert in case of disagreement on dysplasia grade. Agreement between two of three pathologists was established as the final diagnosis. Analysis was performed by , statistics. Due to absence of intestinal metaplasia, 127/920 (14%) patients were excluded. The interobserver agreement for dysplasia [no dysplasia (ND) versus indefinite for dysplasia/low-grade dysplasia (IND/LGD) versus high-grade dysplasia (HGD)/adenocarcinoma (AC)] between non-experts and first panel experts and between initial experts and first panel experts was fair (, = 0.24 and ,,= 0.27, respectively), and substantial for differentiation of HGD/AC from ND/IND/LGD (, = 0.62 and ,,= 0.58, respectively). Conclusions:, There was considerable interobserver variability in the interpretation of ND or IND/LGD in BO between non-experts and experts, but also between expert pathologists. This suggests that less subjective markers are needed to determine the risk of developing AC in BO. [source] Indentation of a free-falling lance penetrometer into a poroelastic seabedINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 2 2005Derek Elsworth Abstract A solution is developed for the build-up, steady and post-arrest dissipative pore fluid pressure fields that develop around a blunt penetrometer that self-embeds from freefall into the seabed. Arrest from freefall considers deceleration under undrained conditions in a purely cohesive soil, with constant shear strength with depth. The resulting decelerating velocity field is controlled by soil strength, geometric bearing capacity factors, and inertial components. At low impact velocities the embedment process is controlled by soil strength, and at high velocities by inertia. With the deceleration defined, a solution is evaluated for a point normal dislocation penetrating in a poroelastic medium with a prescribed decelerating velocity. Dynamic steady pressures, PD, develop relative to the penetrating tip geometry with their distribution conditioned by the non-dimensional penetration rate, UD, incorporating impacting penetration rate, consolidation coefficient and penetrometer radius, and the non-dimensional strength, ND, additionally incorporating undrained shear strength of the sediment. Pore pressures develop to a steady peak magnitude at the penetrometer tip, and drop as PD=1/xD with distance xD behind the tip and along the shaft. Peak induced pressure magnitudes may be correlated with sediment permeabilities, post-arrest dissipation rates may be correlated with consolidation coefficients, and depths of penetration may be correlated with shear strengths. Together, these records enable strength and transport parameters to be recovered from lance penetrometer data. Penetrometer data recorded off La Palma in the Canary Islands (J. Volcanol. Geotherm. Res. 2000; 101:253) are used to recover permeabilities and consolidation coefficients from peak pressure and dissipation response, respectively. Copyright © 2004 John Wiley & Sons, Ltd. [source] The level of polyaromatic hydrocarbons in kajal and surma of major Indian brandsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 3 2009D. K. Patel Synopsis Kajal and surma are eye cosmetics extensively used in Indian subcontinent. Kajal is prepared by burning of vegetable oil and butter oil while surma by grinding of the stones. High performance liquid chromatography and gas chromatography,mass spectrometry instruments were used for quantification and confirmation of 16 polyaromatic hydrocarbons (PAHs). Significant concentration of PAH was found in all the samples examined. The median concentration of PAH ranged from 0.14 (lowest, anthracene) to 31.18 ,g g,1 [dibenz(a,h)anthracene] in kajal sample and from not detectable concentration (naphthalene) to 197.47 ,g g,1 of benzo(a)pyrene in surma sample. Fifteen PAHs were detected in all the samples. Therefore the use of kajal and surma in eye should be strictly restricted. Résumé Le Kajal et le Surma sont des composés très utilisés sur le sous-continent indien pour le maquillage des yeux. Ils sont préparés par calcination d'huile végétale et d'huile de beurre, puis par broyage des résidus. La chromatographie liquide haute pression et la chromatographie en phase gazeuse couplée à la spectrométrie de masse ont été employées pour quantifier et valider seize hydrocarbures polyaromatiques (PAHs). Des concentrations significatives en PAHs ont été trouvées dans les échantillons examinés. La concentration médiane en PAH classées de la faible à la plus élevée est de 0,14 ,g g,1 (anthracène) à 31,18 ,g g,1 (dibenz (a,h) anthracène) dans l'échantillon de Kajal et d'une présence ND (naphtalène) à 197,47 ,g g,1 (benzo (a) pyrène) dans l'échantillon de Surma. Quinze PAHs ont été détectés dans tous les échantillons. En conséquence, l'utilisation de Kajal et de Surma pour la cosmétique des yeux doit être limitée de façon stricte. [source] Mirror exposure for the treatment of body image disturbanceINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 2 2006Sherrie Selwyn Delinsky PhD Abstract Objective Body image disturbance is a risk factor for the development and persistence of eating disorders. Limitations of current treatments for body image disturbance prompted the development of a mirror exposure (ME) treatment. Method ME involves deliberate, planned, and systematic exposure to body image. The approach is nonjudgmental, holistic in focus, and mindful of present emotional experience. Complementary behavioral assignments aim to reduce avoidance and excessive checking. The current study evaluated the effectiveness of ME therapy (in a three-session format) compared with a nondirective (ND) therapy for 45 women with extreme weight and shape concerns. Results ME resulted in significant improvements at termination and follow-up in body checking and avoidance, weight and shape concerns, body dissatisfaction, dieting, depression, and self-esteem. As hypothesized, ME was significantly better than ND on many of the outcome measures. Conclusion ME is an effective treatment for body image disturbance and should be evaluated in the context of treatments for eating disorders. © 2005 by Wiley Periodicals, Inc. [source] Broken symmetry approach and chemical susceptibility of carbon nanotubesINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 8 2010Elena F. Sheka Abstract Constituting a part of odd electrons that are excluded from the covalent bonding, effectively unpaired electrons are posed by the singlet instability of the single-determinant broken spin-symmetry unrestricted Hartree,Fock (UBS HF) SCF solution. The correct determination of the total number of effectively unpaired electrons ND and its fraction on each NDÀ atom is well provided by the UBS HF solution. The NDÀ value is offered to be a quantifier of atomic chemical susceptibility (or equivalently, reactivity) thus highlighting targets that are the most favorable for addition reactions of any type. The approach is illustrated for two families involving fragments of arm-chair (n,n) and zigzag (m,0) single-walled nanotubes different by the length and end structure. Short and long tubes as well as tubes with capped end and open end, in the latter case, both hydrogen terminated and empty, are considered. Algorithms of the quantitative description of any length tubes are suggested. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 [source] Chemical susceptibility of fullerenes in view of Hartree,Fock approachINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 14 2007Elena F. Sheka Abstract Constituting a part of fullerenes odd electrons which are removed from the covalent bonding (Int J Quantum Chem, 2004, 100, 375), effectively unpaired electrons are posed by the singlet instability of the unrestricted Hartree,Fock SCF solution. The feature occurs to be of a particular importance leading to a quantitative description of atomically matched chemical susceptibility of the odd-electron molecular species via the relevant electron density on atoms. A correct determination of the total number of effectively unpaired electrons ND and its partial density NDA is well provided by the UHF solution. The calculation procedure and the obtained results reliability are justified for a set of diatomic molecules and ethylene. Practically full identity of the distribution of both NDA values and independently calculated free valence over atoms of X60 (X = C, Si) and C70 molecules makes it possible to consider the NDA maps as chemical portraits of the fullerenes. The NDA value is offered to be a quantitative pointer of the atom chemical activity thus highlighting targets, which are the most favorable for addition reactions of any type. Basic grounds for a NDA -based computational synthesis of the fullerene derivatives are illustrated for initial steps of C60 fluorination. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [source] A comparative study of single-line and Rietveld strain,size evaluation procedures using MgO ceramicsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2002Suminar Pratapa Strain,size evaluations from diffraction line broadening for MgO ceramic materials have been compared using single-line integral-breadth and Rietveld procedures with the Voigt function. Diffraction data were measured by Bragg,Brentano X-ray diffractometry (XRD), without incident beam monochromatization, and neutron diffractometry (ND) to encompass near-surface and bulk effects, respectively. The specimens consisted of sets of MgO ceramics and MgO,Y2O3 ceramic composites sintered over a range of temperatures. An MgO ceramic sintered at 1723,K for 2,h exhibited slightly less XRD broadening than the standard LaB6 NIST 660 SRM, and was therefore selected to make instrument profile corrections for both XRD and ND data. It was found for both data types that: (a) sintering initially relieves residual strain present in the MgO powder used to sinter the ceramics and also promotes grain growth; (b) residual strain of the MgO ceramic minimizes as the sintering temperature increases, and then increases with further rise in the sintering temperature, presumably as a result of intragranular interactions associated with grain growth; and (c) introduction of the second phase (Y2O3) increases strain and inhibits crystal growth. The single-line and Rietveld methods gave similar strain values from both the XRD and ND data within the limits of experimental error, but there were substantial differences between the single-line and Rietveld size estimates determined with the XRD and ND data. [source] Geographic variation in diapause induction and mode of diapause inheritance in Tetranychus pueraricolaJOURNAL OF APPLIED ENTOMOLOGY, Issue 5 2006Akiyuki Suwa Abstract:, Diapause induction and photoperiodic response curves were determined for 33 strains of Tetranychus pueraricola derived from kudzu vine at three constant temperatures (15, 18 and 20°C) under a short-day condition (10 : 14 h; light : dark). Females of all but one of the strains entered diapause at all three temperatures with little variation in diapause percentages among the strains. The exception was the southernmost strain, which was found to be a non-diapause (ND) strain. The critical photoperiod gradually decreased towards the south at a rate of about 1 h for each 5 degrees of latitude. The diapause strains (D1 and D2) exhibited 100% diapause, whereas the ND strain exhibited 0% diapause. By crossing these strains, we determined that ,non-diapause' was a dominant character over ,diapause' and the character was controlled by simple Mendelian inheritance. To clarify why the female progeny from the crosses between the D1 and ND strains did not segregate into the diapause and non-diapause phenotypes in a 1:1 ratio in the B1 generation, round-robin crosses were carried out among the three strains. The results showed that the F1 generation was reproductively compatible and showed high egg hatchability with a female-biased sex ratio. In the B1 generation, the crosses between the D1 and ND strains and between the D1 and D2 strains exhibited extremely low egg hatchability and produced mostly female progeny, whereas offspring from the crosses between the D2 and ND strains showed more than 50% hatchability for B1 eggs and a female-biased sex ratio. Thus, the absence of segregation observed in the crosses between the D1 and ND strains appears to be due to the severe hybrid breakdown that occurred in the B1 generation. [source] Vascular catheterization is difficult in infants with Down syndromeACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2009D. S. SULEMANJI Background: Our aim was to compare difficulties in vascular access interventions in infants with and without Down Syndrome (DS) undergoing congenital heart surgery. Methods: The anesthesia records of infants with DS undergoing congenital heart surgery (Group DS, n=61) were reviewed and matched with records of infants without DS (Group ND, n=61). Vascular cannulation sites, the experience of the anesthesiologists performing each procedure, the number of clinicians who attempted each procedure until it was successfully performed, and the number of attempts for each catheterization were recorded. Results: The rate of unsuccessful peripheral venous cannulation in any of the four extremities was higher in Group DS (P=0.026). The success rate of radial artery cannulation was lower in Group DS (P=0.048). Although the total number of attempts for arterial cannulation was higher in Group DS, the difference was not statistically significant (P=0.058). However, in Group DS, the clinician who was able to cannulate the artery successfully required a significantly higher number of attempts at cannulation (P=0.011). For central venous catheterization, cannulation site and the number of attempts required before success was achieved were similar in both groups. The specialist-to-resident ratio was higher in Group DS (P=0.037). Conclusion: Our results indicate a trend toward clinicians having more difficulty performing arterial and peripheral venous catheterizations in infants with DS compared with performing the same procedure in infants without DS. Anesthesiologists should be prepared for catheterization difficulties in this patient population. In infants with DS, we recommend that catheterizations be performed by more experienced physicians. [source] Synthesis and properties of poly(carbonate-urethane) consisting of alternating carbonate and urethane moietiesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2006Bungo Ochiai Abstract Poly(carbonate-urethane) consisting of alternating carbonate and urethane moieties (poly(HC-MDI)) was prepared by polyaddition of 4,4,-diphenylmethane diisocyanate (MDI) and a monocarbonate diol bis(3-hydroxypropyl)carbonate (HC), prepared by hydrolysis of a six-membered spiroorthocarbonate 1,5,7,11-tetraoxa-spiro[5.5]undecane. The polyaddition proceeds without concomitant side reactions including carbonate exchange reaction and affords the desired poly(carbonate-urethane). The hydrolysis and thermal behaviors of poly(HC-MDI) were compared with those of the analogous polyurethane carrying no carbonate structure (poly(ND-MDI)) prepared from MDI and 1,9-nonanediol (ND). Although the glass transition behaviors are almost identical, poly(HC-MDI) is less crystalline than poly(ND-MDI). Poly(HC-MDI) is more susceptible to hydrolysis than poly(ND-MDI) probably due to the higher polarity and the lower crystallinity. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2802,2808, 2006 [source] Dual Diagnosis: Prevalence, Risk Factors, and Relationship With Suicide Risk in a Nationwide Sample of French PrisonersALCOHOLISM, Issue 1 2009Michael Lukasiewicz Background:, Axis I psychiatric disorders (PD) and substance use disorders (SUD) are common in prison, but only few studies have focused on their association in this setting. Dual diagnosis (DD) (the co-occurrence of a SUD and any axis I disorder) is known to have a poorer prognosis and to require more intense supportive care. Objectives:, The objectives of this study were (1) to describe prisoners with DD (prevalence and characteristics); (2) to compare DD prisoners with 3 other groups of prisoners: no diagnosis (ND), SUD alone, or other isolated PD; and (3) to evaluate the impact of DD on suicide risk in prison. Method:, A random stratified strategy was used to select 23 various types of prisons and 998 prisoners. Diagnoses were assessed using a unique procedure, each prisoner being evaluated by 2 psychiatrists, 1 junior, using a structured interview (MINI 5 plus), and 1 senior, using an open clinical interview. Following interviews, clinicians met to establish a list of diagnoses. Cloninger's temperament and character inventory was also used. Results:, Of the prisoners, 26.3% had a DD. DD prevalence was almost 80% in prisoners with SUD, while only one-third of the prisoners with an axis I PD had co-morbid SUD. No significant differences were observed in drug use patterns between DD and SUD without co-morbid PDs. DD showed the strongest association with suicide risk [OR = 5.7 (1.7,4.6)]. Conclusion:, DD is very frequent in prison and is a major risk factor for suicide. Systematic psychiatric/SUD screening of prisoners with either a SUD or an axis I PD should be encouraged. [source] Effect of light filters on reading speed in normal and low vision due to age-related macular degenerationOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 1 2004Frank Eperjesi Abstract Purpose:, To investigate the effects of light filters on reading speed in normal and low vision due to age-related macular degeneration (AMD). Methods:, Reading speed was determined for 12 subjects with normal vision and 12 subjects with non-exudative AMD using stationary lowercase nonsensical print in Times Roman font and four light filters; a yellow Corning Photochromic Filter (CPF) 450, a grey neural density (ND) filter, an individual filter obtained using the Intuitive Colorimeter® and a clear filter. Results:, There was no statistically significant light filter effect on reading speed for the normal subjects. The AMD group demonstrated a statistically significant 5% average improvement in reading speed with the CPF450 compared with the other filters although some AMD subjects had improvements of 10,15%. Conclusions:, Light filters obtained using the Intuitive Colorimeter® performed poorly when compared with the CPF450, ND and clear filters for both the study groups. For the AMD group, average reading speed was statistically greater with the CPF450 than the other filters, however it is questionable whether the improvement (5%) would be clinically significant. As some of the subjects with AMD had greater improvements with the CPF450 we advocate clinical assessment of light filters using existing protocols on an individual basis. [source] Retinopathy of prematurity: Mutations in the Norrie disease gene and the risk of progression to advanced stagesPEDIATRICS INTERNATIONAL, Issue 2 2001Mohammad Z Haider AbstractBackground: Retinopathy of prematurity (ROP) is a retinal vascular disease that occurs in infants with short gestational age and low birth weight and may lead to retinal detachment and blindness. Missense mutations in the Norrie disease (ND) gene have been associated with the risk of progression to advanced stages in cases of ROP from the US and also in clinically similar ND and familial exudative vitreoretinopathy. Methods: We have screened two ND gene mutations, namely A105T and Val60Glu, by polymerase chain reaction,restriction fragment length polymorphism (PCR-RFLP) and allele-specific PCR methods, respectively, in 210 Kuwaiti premature newborns to replicate these findings in a different ethnic group. Results: In the Kuwaiti premature newborn cohort, 115 of 210 babies had no eye problems and served as controls, while 95 were cases of ROP. In 71 of 95 ROP cases, the disease regressed spontaneously on or before stage 3, while in 24 of 95 ROP cases the disease progressed to advanced stages 4 and 5. In case of missense mutation (A105T), the AA genotype was detected in 96% of controls compared with 87% of ROP cases (NS); similarly no significant difference was found between spontaneously regressed ROP cases and those who progressed to advanced stages. For the Val60Glu mutation, no significant association was detected between the genotype and progression of ROP to advanced stages. Conclusions: Unlike data from the US, our findings from a Kuwaiti cohort of ROP cases and controls suggest a lack of association between the two ND gene mutations (A105T and Val60Glu) and ROP and the risk of progression of the disease to advanced stages. [source] Compensation in boron-doped CVD diamondPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 9 2008Markus Gabrysch Abstract Hall-effect measurements on single crystal boron-doped CVD diamond in the temperature interval 80,450 K are presented together with SIMS measurements of the dopant concentration. Capacitance,voltage measurements on rectifying Schottky junctions manufactured on the boron-doped structures are also presented in this context. Evaluation of the compensating donor (ND) and acceptor concentrations (NA) show that in certain samples very low compensation ratios (ND/NA below 10,4) have been achieved. The influence of compensating donors on majority carrier transport and the significance for diamond device performance are briefly discussed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Electrical and optical properties of thick highly doped p-type GaN layers grown by HVPEPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2008A. Usikov Abstract In this paper we report 3-7 ,m thick p-GaN growth by hydride vapor phase epitaxy (HVPE) on sapphire substrates. Mg impurity was used for doping. As-grown GaN layers had p-type conductivity with concentration NA -ND up to 3×1019 cm,3. Mg atom concentration was varied from 1017 to 1020 cm,3. Hydrogen concentration was about 10 times less than that for Mg, which may explain effective p-type doping for as-grown GaN layers. Micro-cathodoluminescence revealed a columnar-like structure of the GaN layers with a non-uniform distribution of material regions having dominant 362 nm or 430 nm luminescence. Use of these thick p-GaN layers to grow InGaN-based blue and green LEDs by the HVPE is demonstrated. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Peculiarities of dislocation photoluminescence in germanium with quasi-equilibrium dislocation structurePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 8 2007S. Shevchenko Abstract The dislocation photoluminescence (DPL) at 4.2 K was studied in germanium (Ge) single crystals of n- and p-type with quasi-equilibrium structure of 60° dislocations. The DPL spectra for different samples were decomposed on Gaussian lines (Gm -lines) over the range 0.47-0.58 eV characterized by practically the same peak energies Em and the widths under 15 meV. The G-lines with Em , 0.55 eV were ascribed to the radiation of regular segments of 60° dislocations with different stacking fault (SF) widths , between 30 and 90° partials. An increase of the dislocations density up to ND , 107 cm,2 was found to result in a considerable growth of the intensity of the G-lines with Em <0.513 eV. The factors, which promote the appearance of different , values for quasi-equilibrium 60° dislocation structure, are discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Effects of Mg fluctuation on the electrical and optical properties in p-GaN/undoped GaN layers dependent on the growth temperaturePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2003C. S. Kim Abstract The effects of heavly Mg doping dependent on the growth temperature of p-GaN layers grown on undoped GaN layers by metalorganic chemical vapor deposition (MOCVD) on electrical and optical properties were studied by capacitance,voltage (C,V) and temperature-dependent photoluminescence (TDPL), respectively. At high growth temperature of p-GaN above 1110 °C, optical microscopy images as well as atomic force microscopy (AFM) images show polygonal hillocks on heavily Mg-doped GaN surface. It was also found that fluctuation of Mg concentration ([Mg]) measured by secondary ion mass spectroscopy (SIMS) was increased with increasing growth temperature. These phenomena were appeared to decrease NA,ND and change PL emission from 3.1,3.2 eV of conduction band-to-shallow Mg acceptor (e, A) transition to 2.8,2.9 eV of Mg-related deep donor-to-acceptor pair (DAP) transition. [source]
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