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Sample records for beck cycle

  1. Ulrich Beck

    DEFF Research Database (Denmark)

    Sørensen, Mads P.; Christiansen, Allan

    Since the 1980s, Ulrich Beck has worked extensively on his theories of second modernity and the risk society. The book Ulrich Beck provides an extensive and thorough introduction to the German sociologist’s collected works. The book covers his sociology of work, his theories of individualization......, globalization and subpolitics, his world famous theory of the risk society and second modernity as well as his latest work on cosmopolitanism. Focusing on the theory outlined in Beck’s chief work, Risk Society, and on his theory of second modernity, the book explains the sociologist’s ideas and writing...

  2. Intersecções: De Beck a ... Beck.

    OpenAIRE

    Cardoso, Francisco

    1995-01-01

    Aaron Beck é um dos pioneiros da psicoterapia cognitiva, realçando-se a sua especial importância no domínio do estudo e intervenção cognitivo-comportamental da depressão. Apresenta-se a sua proposta de ligação entre a depressão com a organização da personalidade, de autonomia versus sociotropa, para o entendimento e intervenção psicoterapêutica.

  3. Kuu plaat : Beck "Guero". Plaadid kauplusest Lasering

    Index Scriptorium Estoniae

    2005-01-01

    Heliplaatidest: Beck "Guero", Common "Be", Stupid F ja Hash "Koodeks: R.L.V.", Kulo "Onarhia", Natalie Imbruglia "Counting Down the Days", New Order "Waiting for the Sirens' Call", Human Ground "Human Ground"

  4. Aaron Temkin Beck (born July 18, 1921- Biography

    Directory of Open Access Journals (Sweden)

    K. Fatih Yavuz

    2012-07-01

    Full Text Available he American Academy of Arts and Sciences in 2007. Beck is noted for his research in psychotherapy, psychopathology, suicide, and psychometrics, which led to his creation of cognitive therapy, for which he received the 2006 Lasker-DeBakey Clinical Medical Research Award, and the Beck Depression Inventory (BDI, one of the most widely used instruments for measuring depression severity. Beck is also known for his creation of the Beck Hopelessness Scale and the Beck Anxiety Inventory, and has founded the Beck Institute in Philadelphia, Pennsylvania, in which his daughter, Dr. Judith Beck, works. He is married with four children, Roy, Judy, Dan, and Alice. He has eight grandchildren.the American Academy of Arts and Sciences in 2007. Beck is noted for his research in psychotherapy, psychopathology, suicide, and psychometrics, which led to his creation of cognitive therapy, for which he received the 2006 Lasker-DeBakey Clinical Medical Research Award, and the Beck Depression Inventory (BDI, one of the most widely used instruments for measuring depression severity. Beck is also known for his creation of the Beck Hopelessness Scale and the Beck Anxiety Inventory, and has founded the Beck Institute in Philadelphia, Pennsylvania, in which his daughter, Dr. Judith Beck, works. He is married with four children, Roy, Judy, Dan, and Alice. He has eight grandchildren.

  5. Erich Beck şi Bucovina

    Directory of Open Access Journals (Sweden)

    Mihai Iacobescu

    2006-11-01

    Full Text Available L'historien de Suceava, Mihai Iacobescu réalise avec sensibilité et talent, dans la première partie de l'étude ci-jointe un portrait authentique de l'érudit Erich Beck, mettant en évidence sa personnalité et son envergure intellectuelle. L'évocation de la dimension culturelle de la biographie de l'érudit allemand, complétée par la perspective nostalgique et les accents anecdotiques est occasionnée par la cérémonie dans laquelle l'Université "Etienne Le Grand" de Suceava a accordé à Monsieur Erich Beck le titre de Doctor Honoris Causa, le 22 novembre 2003. La seconde partie de l'article comprend une synthèse de Laudatio soutenue à cette occasion-là. La présentation des contributions de Erich Beck détermine l'historien Mihai Iacobescu à caractériser l'érudit allemand comme "vraiment le Patriarche de la bibliographie de la Bucovine", et ses volumes bibliographiques comme un "monolithe (… durable".

  6. Some psychometric characteristics of the Beck's Hopelessness Scale

    Directory of Open Access Journals (Sweden)

    Novović Zdenka

    2005-01-01

    Full Text Available The study tested reliability and construct validity of Serbian translation of Beck's Hopelessness scale on a sample of patients diagnosed as a depressive, anxious and anxious-depressive disorder. Scale was found to have a high degree of internal consistency (Cronbach alpha = 0.91. Principal component analysis, with Scree-test as the criterion of extraction, provided single factor as the best solution. Hopelessness Scale highly correlated with symptoms of depression, low self-concept and depressive automatic thoughts which the authors interpreted as the confirmation of Beck's theory. The hypothesis that hopelessness is construct specific to depression and not to anxiety is, also, confirmed.

  7. The prevalence of mycotoxins in Kashin-Beck disease

    OpenAIRE

    Haubruge, Eric; Chasseur, Camille; Debouck, Catherine; Rooze, Marcel; Begaux, Françoise; Suetens, Carl; Mathieu, Françoise; Michel, Valérie; Gaspar, Charles; Nolard, Nicole; Lognay, Georges

    2001-01-01

    Mycotoxins are naturally occurring toxic chemical compounds produced by fungi infesting agricultural crops both during their growth and storage. Such secondary metabolites, when ingested, can produce toxic syndromes in humans. As it has been suggested that mycotoxins might be involved in the development of Kashin-Beck disease (KBD), we undertook a survey of barley grains of KBD-affected families and non-affected families in that country. We found, by thin layer chromatography, a hitherto unkn...

  8. Nano and viscoelastic Beck's column on elastic foundation

    CERN Document Server

    Atanackovic, Teodor M; Zorica, Dusan

    2014-01-01

    Beck's type column on Winkler type foundation is the subject of the present analysis. Instead of the Bernoulli-Euler model describing the rod, two generalized models will be adopted: Eringen non-local model corresponding to nano-rods and viscoelastic model of fractional Kelvin-Voigt type. The analysis shows that for nano-rod, the Herrmann-Smith paradox holds while for viscoelastic rod it does not.

  9. Cognitiva (TC de Beck en una muestra costarricense

    Directory of Open Access Journals (Sweden)

    Hannia Cabezas Pizarro

    2006-01-01

    Full Text Available En este estudio se explora una posible relación empírica entre la terapia racional emotivoconductual (TREC de Ellis y la terapia cognitiva (TC de Beck, dos de los modelos más conspicuos en el campo de la psicoterapia cognitiva actual. Si bien este modelo utiliza el término “cognitivo” en forma tal que se encuentra asociado con el afecto, la fisiología y la conducta (Dobson, 1986, sostiene que las perturbaciones emocionales, en esencia, son causadas por el proceso cognitivo del individuo. En esta investigación, se trabajó con una muestra de 200 estudiantes de la Universidad de Costa Rica de diferentes áreas a quienes se les aplicaron las escalas de: Attitudes and Beliefs Inventory (ABI [Escala de Actitudes y Creencias], y el Beck Depression Inventory, 2ª edición (BDI-II [Inventario de Depresión de Beck], escalas que fueron adaptadas al español. El análisis estadístico de los datos confirma empíricamente la relación entre ambos modelos.

  10. Ulrich Beck : ostmine võib olla sama mõjus poliitiline osalusvorm kui valimaskäimine / Ulrich Beck ; interv. Indrek Ibrus

    Index Scriptorium Estoniae

    Beck, Ulrich

    2005-01-01

    Sotsioloog on seisukohal, et tänapäeval, kus teadusest ja majandusest on kujunenud poliitika, saab erasektorit ja teadlasi mõjutada tarbijakäitumise ning riikidevahelise koostöö suurendamisega. Lisa: Ulrich Beck

  11. Use of the Beck Anxiety and Depression Inventories for Primary Care with Medical Outpatients.

    Science.gov (United States)

    Beck, Aaron T.; Steer, Robert A.; Ball, Roberta; Ciervo, Carman A.; Kabat, Mark

    1997-01-01

    The effectiveness of the Beck Anxiety and Beck Depression Inventories for Primary Care for discriminating 56 primary care patients with and without diagnosed anxiety and mood disorders. Use of these instruments to screen primary care patients before conducting extensive diagnostic evaluations with them is discussed. (SLD)

  12. Pretreatment Beck Depression Inventory score is an important predictor for Post-treatment score in infertile patients: a before-after study

    OpenAIRE

    Ramezanzadeh Fatemeh; Aghahosseini Marzieh; Alleyassin Ashraf; Khademi Afsaneh; Abhari Ali

    2005-01-01

    Abstract Background The experience of infertility can be extremely stressful. Some of the risk factors for depression in infertility are being female, repeated unsuccessful treatment cycles or a 2 to 3 year history of infertility, low socioeconomic status, foreign nationality, lack of partner support, life events and previous depression. In this study, we analyzed the Beck Depression Inventory score at the beginning and the end of infertility treatment, to determine which factors may influenc...

  13. Consistencia interna y estructura factorial de la Escala de Desesperanza de Beck en estudiantes mexicanos

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    Martha Córdova Osnaya

    2011-12-01

    Full Text Available Internal consistency and factorial structure of the Beck Hopelessness Scale among Mexican students The Beck Hopelessness Scale was applied in a sample of 971 male and female students, chosen at random sampling from Mexico City, with an average age of 16.75 years. Results were compared to those reported by Beck, Weissman, Lester and Trexler (1974. Results showed adequate reliability (≥ 0.70 in the total sample by gender. Factorial structure matched only in the Affective factor as reported by Beck et al. (1974 with respect to the total sample. Differences in saturation and factorial structure in both sexes were observed. It was concluded that the factor structure of Beck Hopelessness Scale registers different factor structure in the total sample, according to sex.

  14. [Gunnar Meyer. "Besitzende Bürger" und "Elende Sieche". Lübecks Gesellschaft im Spiegel ihrer Testamente 1400-1449] / Dennis Hortmuth

    Index Scriptorium Estoniae

    Hormuth, Dennis

    2012-01-01

    Arvustus: Gunnar Meyer. "Besitzende Bürger" und "Elende Sieche". Lübecks Gesellschaft im Spiegel ihrer Testamente 1400-1449. (Verhöffentlichungen zur Geschichte der Hansestadt Lübeck. B. 48). (Lübeck, 2010)

  15. Psychometric Properties of the Beck Scale for Depression (Beck Depression Inventory BDI-II)--A Study on a Sample of Students in the State of Kuwait Universities

    Science.gov (United States)

    Dahem, Ahmed Mohammed Faleh

    2016-01-01

    The study aimed to identify the psychometric properties of the Beck Depression Inventory (BDI-II) the Arabized version by Gharib (2000); the study sample consisted of 500 male and female students from the Kuwaiti universities by 250 males and 250 females on whom the BDI-II scale was applied twice; the psychometric characteristics such as the…

  16. Validity study of the Beck Anxiety Inventory (Portuguese version by the Rasch Rating Scale model

    Directory of Open Access Journals (Sweden)

    Sónia Quintão

    2013-01-01

    Full Text Available Our objective was to conduct a validation study of the Portuguese version of the Beck Anxiety Inventory (BAI by means of the Rasch Rating Scale Model, and then compare it with the most used scales of anxiety in Portugal. The sample consisted of 1,160 adults (427 men and 733 women, aged 18-82 years old (M=33.39; SD=11.85. Instruments were Beck Anxiety Inventory, State-Trait Anxiety Inventory and Zung Self-Rating Anxiety Scale. It was found that Beck Anxiety Inventory's system of four categories, the data-model fit, and people reliability were adequate. The measure can be considered as unidimensional. Gender and age-related differences were not a threat to the validity. BAI correlated significantly with other anxiety measures. In conclusion, BAI shows good psychometric quality.

  17. [The history of the Institute of Hygiene of the Medical College of Lübeck].

    Science.gov (United States)

    Preuner, R

    1986-05-01

    The "Institute of Hygiene" of the Hanseatic town of Lübeck was founded in 1946 by Prof. Dr. Franz Schültz on account of the then prevailing epidemic situation mainly caused by the rapid spread of typhoid fever. The local responsibility of the Institute extended to the town itself and to the two hospitals "South" and "East", with the latter originating from the asylum of Strecknitz after its tragic destruction. In 1950 Franz Schütz was appointed ordinary professor and director of the Institute of Hygiene of the University of Göttingen. In Lübeck he was succeeded by Prof. Dr. Hans Schubert, last senior physician of the Institute of Hygiene of the University of Königsberg. He served a very short term in Lübeck, for he died as early as 1951 after seven months' tenure. He was succeeded in office by Prof. Dr. Rudolf Preuner in 1952. During his term of office the ties with the hospitals were severed and the Institute became independent. Endeavors to found a College started in the early sixties. In November 1964 the Medical Academy of Lübeck was created as Second Medical Faculty of the University of Kiel; in 1974 it was converted into the independent Medical College of Lübeck with a presidial constitution. In 1979 Rudolf Preuner retired as professor emeritus. His successor in office was Prof. Dr. Johannes Beckert. In 1985 the College was raised to the Medical University of Lübeck. PMID:3092506

  18. Den sene Derrida, eller: Er Claus Beck-Nielsen et spøgelse?

    DEFF Research Database (Denmark)

    Rösing, Lilian Munk

    2009-01-01

    This article is about hosting the ghost. In Spectres de Marx (1993) Derrida introduces the ghost which seems to condense in one figure the important themes of his late writings: the address, the other, the ethical turn, the event, the mourning, the reality of immateriality, the guest. The article...... turns to the paternal ghost from Shakespeare's Hamlet, as well as to the most ghost-like artist on the Danish contemporary art scene: Claus Beck-Nielsen, who some years ago declared himself dead. Is Claus Beck-Nielsen really a ghost? That is the question....

  19. Psychometric Evaluation of the Beck Anxiety Inventory with Older Medical Patients.

    Science.gov (United States)

    Wetherell, Julie Loebach; Arean, Patricia A.

    1997-01-01

    When 197 disadvantaged older medical patients completed the Beck Anxiety Inventory, the instrument demonstrated high internal consistency and no significant differences by sex or race, suggesting that it is appropriate for use with diverse populations. Total instrument scores correlated negatively with age. (SLD)

  20. Differentiation of Depressive Disorders from Generalized Anxiety by the Beck Depression Inventory.

    Science.gov (United States)

    Steer, Robert A.; And Others

    1986-01-01

    The Beck Depression Inventory was administered to 35 outpatients diagnosed as primary generalized anxiety disorders and 101 outpatients diagnosed as primary major-depression and dysthymic disorders. A backward stepwise-discriminant analysis revealed that Sadness and Loss of Libido were the only two symptoms that meaningfullly distinguished between…

  1. Validating the Beck Depression Inventory-II for Hong Kong Community Adolescents

    Science.gov (United States)

    Byrne, Barbara M.; Stewart, Sunita M.; Lee, Peter W. H.

    2004-01-01

    The primary purpose of this study was to test for the validity of a Chinese version of the Beck Depression Inventory-II (C-BDI-II) for use with Hong Kong community (i.e., nonclinical) adolescents. Based on a randomized triadic split of the data (N = 1460), we conducted exploratory factor analysis on Group1 (n = 486) and confirmatory factor…

  2. Meta-Analysis of the English Version of the Beck Depression Inventory-Second Edition

    Science.gov (United States)

    Erford, Bradley T.; Johnson, Erin; Bardoshi, Gerta

    2016-01-01

    This meta-analysis reviewed 144 studies from 1996 to 2013 using the Beck Depression Inventory-Second Edition. Internal consistency was 0.89 and test-retest reliability 0.75. Convergent comparisons were robust across 43 depression instruments. Structural validity supported both one- and two-factor solutions and diagnostic accuracy varied according…

  3. A Factor Analytic Study of the Beck Depression Inventory for Female College Students.

    Science.gov (United States)

    Hedl, John J., Jr.

    Previous factor studies of the Beck Depression Inventory (BDI) have not analyzed the item data as a function of sex, or reported more than one factor solution. To further study the factor structure of the BDI, items were factor analyzed and multiple solutions were examined for simple structure, parsimony, and psychological meaningfulness. A sample…

  4. Can Beck's Theory of Depression and the Response Style Theory Be Integrated?

    Science.gov (United States)

    Possel, Patrick

    2011-01-01

    There are obvious similarities between the cognitive constructs of A. T. Beck's (1976) cognitive theory and the response style theory (S. Nolen-Hoeksema & J. Morrow, 1991). Different propositions of J. A. Ciesla and J. E. Roberts (2007) and S. Lyubomirsky and S. Nolen-Hoeksema (1993, 1995) concerning associations of 2 response styles, brooding and…

  5. Confirmatory Factor Analysis of the Beck Depression Inventory-II in Bariatric Surgery Candidates

    Science.gov (United States)

    Hall, Brian J.; Hood, Megan M.; Nackers, Lisa M.; Azarbad, Leila; Ivan, Iulia; Corsica, Joyce

    2013-01-01

    Screening for depression is an integral part of psychological evaluations conducted prior to bariatric surgery. The Beck Depression Inventory-II (BDI-II) is the most commonly used measure of depression in these treatment evaluations. The reliability and validity of the BDI-II has not yet been evaluated within bariatric surgery-seeking samples,…

  6. Psychometric Properties of the Beck Depression Inventories When Used with an Elderly Population.

    Science.gov (United States)

    Watkins, Arleen J.; Kligman, Evan

    The Beck Depression Inventory (BDI) is a self-reported inventory tapping current feelings only. A short form was published in 1972 consisting of 13 items from the original BDI, called the BDI-SF. In 1978 the original version was modified to eliminate double negative statements and alternative ways of asking the same question and then referred to…

  7. Measurement Invariance and Latent Mean Differences of the Beck Depression Inventory II across Gender Groups

    Science.gov (United States)

    Wu, Pei-Chen

    2010-01-01

    This study examined measurement invariance (i.e., configural invariance, metric invariance, scalar invariance) of the Chinese version of Beck Depression Inventory II (BDI-II-C) across college males and females and compared gender differences on depression at the latent factor mean level. Two samples composed of 402 male college students and 595…

  8. Longitudinal Stability of the Beck Depression Inventory II: A Latent Trait-State-Occasion Model

    Science.gov (United States)

    Wu, Pei-Chen

    2016-01-01

    In a six-wave longitudinal study with two cohorts (660 adolescents and 630 young adults), this study investigated the longitudinal stability of the Beck Depression Inventory II (BDI-II) using the Trait-State-Occasion (TSO) model. The results revealed that the full TSO model was the best fitting representation of the depression measured by the…

  9. Validation of the Urdu Translation of the Beck Scale for Suicide Ideation

    Science.gov (United States)

    Ayub, Nailah

    2008-01-01

    This study aimed at developing an Urdu version of the Beck Scale for Suicide Ideation (BSI) for use with Pakistani adolescents and young adults. For this purpose, the English BSI was translated into Urdu and tested for psychometric properties. The analyses were carried out with data from a sample of 904 adolescents and young adults from eight…

  10. A counterexample to Beck's conjecture on the discrepancy of three permutations

    CERN Document Server

    Newman, Alantha

    2011-01-01

    Given three permutations on the integers 1 through n, consider the set system consisting of each interval in each of the three permutations. Jozsef Beck conjectured (c. 1987) that the discrepancy of this set system is O(1). We give a counterexample to this conjecture: for any positive integer n = 3^k, we exhibit three permutations whose corresponding set system has discrepancy Omega(log(n)). Our counterexample is based on a simple recursive construction, and our proof of the discrepancy lower bound is by induction. This example also disproves a generalization of Beck's conjecture due to Spencer, Srinivasan and Tetali, who conjectured that a set system corresponding to l permutations has discrepancy O(sqrt(l)).

  11. El legado psicoanalítico en la terapia cognitiva de Aaron Beck

    Directory of Open Access Journals (Sweden)

    Guido Pablo Korman

    2013-12-01

    Full Text Available The psychodynamic model in which Beck was formed tried to include psychoanalysis into the scientific model. This was consistent with the aims of many clinical researchers in the 1950-1960 decades in the United States. This will take him, years later, to develop the cognitive therapy. In this paper we will focus on Beck psychoanalytic training and his firsts publications as a specialist in psychiatry during his hospital practice (at the Austen Riggs Clinic and in the Valley Forge Army Hospital. We will analyze his first hypotheses, trying to trace the evidence of his mode of action as a psychoanalyst. This formation will subsequently lead him to rethink the psychoanalytic theory, a fact that will be the key to explain the features that will adopt cognitive therapy.

  12. Effects of chondroitin sulfate and glucosamine in adult patients with Kaschin-Beck disease

    DEFF Research Database (Denmark)

    Zhang, Ya-xu; Dong, Wei; Liu, Hui;

    2010-01-01

    The purpose is to investigate the effects of chondroitin sulfate and glucosamine on adult patients with Kaschin-Beck disease (KBD). A total of 80 patients, aged over 40 years, were randomized into two groups receiving either 1,600 mg oral mixture of chondroitin sulfate and glucosamine or placebo......). But the overall mean change in joint space was significant between the two groups (P glucosamine might play a protective role in preserving articular cartilage and provide...

  13. Application of the Beck model to stock markets: Value-at-Risk and portfolio risk assessment

    Science.gov (United States)

    Kozaki, M.; Sato, A.-H.

    2008-02-01

    We apply the Beck model, developed for turbulent systems that exhibit scaling properties, to stock markets. Our study reveals that the Beck model elucidates the properties of stock market returns and is applicable to practical use such as the Value-at-Risk estimation and the portfolio analysis. We perform empirical analysis with daily/intraday data of the S&P500 index return and find that the volatility fluctuation of real markets is well-consistent with the assumptions of the Beck model: The volatility fluctuates at a much larger time scale than the return itself and the inverse of variance, or “inverse temperature”, β obeys Γ-distribution. As predicted by the Beck model, the distribution of returns is well-fitted by q-Gaussian distribution of Tsallis statistics. The evaluation method of Value-at-Risk (VaR), one of the most significant indicators in risk management, is studied for q-Gaussian distribution. Our proposed method enables the VaR evaluation in consideration of tail risk, which is underestimated by the variance-covariance method. A framework of portfolio risk assessment under the existence of tail risk is considered. We propose a multi-asset model with a single volatility fluctuation shared by all assets, named the single β model, and empirically examine the agreement between the model and an imaginary portfolio with Dow Jones indices. It turns out that the single β model gives good approximation to portfolios composed of the assets with non-Gaussian and correlated returns.

  14. EFFECT OF SELENIUM ON IMMUNE FUNCTION OF ERYTHROCYTE IN KASHIN-BECK DISEASE

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Kashin-Beck disease(KBD)is an endemicchronic osteoarthropathy affecting about2.5millionresidents with over30million at risk in China[1].KBD manifests large defor med joins with muscularastrophy.Its major pathology is a chondrocyte nec-rosis in deep zone of growth plates[2].Etiology ofKBDis still not very clear,but it is supposed thatseleniumdeficiency is likely to be a cofactor in itsdevelopment.Seleniumis unevenly distributed onthe surfaceof the earth and consequently the seleniumconcen-tration varies wide...

  15. Cross-cultural examination of measurement invariance of the Beck Depression Inventory-II.

    Science.gov (United States)

    Dere, Jessica; Watters, Carolyn A; Yu, Stephanie Chee-Min; Bagby, R Michael; Ryder, Andrew G; Harkness, Kate L

    2015-03-01

    Given substantial rates of major depressive disorder among college and university students, as well as the growing cultural diversity on many campuses, establishing the cross-cultural validity of relevant assessment tools is important. In the current investigation, we examined the Beck Depression Inventory-Second Edition (BDI-II; Beck, Steer, & Brown, 1996) among Chinese-heritage (n = 933) and European-heritage (n = 933) undergraduates in North America. The investigation integrated 3 distinct lines of inquiry: (a) the literature on cultural variation in depressive symptom reporting between people of Chinese and Western heritage; (b) recent developments regarding the factor structure of the BDI-II; and (c) the application of advanced statistical techniques to the issue of cross-cultural measurement invariance. A bifactor model was found to represent the optimal factor structure of the BDI-II. Multigroup confirmatory factor analysis showed that the BDI-II had strong measurement invariance across both culture and gender. In group comparisons with latent and observed variables, Chinese-heritage students scored higher than European-heritage students on cognitive symptoms of depression. This finding deviates from the commonly held view that those of Chinese heritage somatize depression. These findings hold implications for the study and use of the BDI-II, highlight the value of advanced statistical techniques such as multigroup confirmatory factor analysis, and offer methodological lessons for cross-cultural psychopathology research more broadly.

  16. El legado psicoanalítico en la terapia cognitiva de Aaron Beck

    Directory of Open Access Journals (Sweden)

    Guido Pablo Korman

    2013-01-01

    Full Text Available El psicoanálisis en el que Beck se formó tenía como objetivo incluir al psicoanálisis dentro del modelo científico. Esto era consistente con los intereses de un gran número de investigadores clínicos en los Estados Unidos durante las décadas de 1950 y 1960. Este trayecto intelectual lo llevará, años después, a desarrollar la terapia cognitiva. En este trabajo nos enfocaremos en el entrenamiento psicoanalítico de Beck así como en las primeras publicaciones de éste como especialista en psiquiatría durante su práctica hospitalaria en la Clínica de Austen Riggs y en el Hospital Valley Forge Army. Analizaremos sus primeras hipótesis, intentando rastrear los indicios de su modo de actuar como psicoanalista. Esta misma formación posteriormente lo llevará a un replanteo del modelo psicoanalítico, hecho que será clave para explicar las características que adoptará la terapia cognitiva.

  17. Psychometric properties of the Beck Depression Inventory-II in nonclinical adolescent samples.

    Science.gov (United States)

    Osman, Augustine; Barrios, Francisco X; Gutierrez, Peter M; Williams, John E; Bailey, Jennifer

    2008-01-01

    This study examined the factor structure and psychometric properties of the Beck Depression Inventory-II (BDI-II; A. T. Beck, Steer, & Brown, 1996) in samples of high-school adolescents (N=414; 210 boys and 204 girls, ages 14-18 years). Confirmatory factor analyses provided satisfactory fit estimates for the two- and three-factor oblique solutions reported frequently in the extant literature. The solution to a general factor with domain-specific somatic and cognitive-affective factors was examined as an alternative model to previously established models for the current high-school sample data. Results provided stronger support for the general factor model. Estimates of internal consistency for scores on this instrument were high (coefficient alpha=.92, average interitem correlation=.35). The mean BDI-II total score for the nonclinical samples (M=12.50, SD=10.50) was compared with the mean scores reported for various adolescent normative samples in the extant literature. The BDI-II total score correlated moderately and significantly with scores on self-report measures of hopelessness (r=.63), anxiety (r=.53), and suicide-related behaviors (r=.57), providing support of adequate correlates for the BDI-II. Estimates of known-groups validity were evaluated using data from a small sample of 167 clinical adolescent inpatients. Specific study findings, limitations, and recommendations are discussed. PMID:18161034

  18. EFFECT OF SELENIUM ON IMMUNE FUNCTION OF ERYTHROCYTE IN KASHIN-BECK DISEASE

    Institute of Scientific and Technical Information of China (English)

    Dai Xiaoxia; Xiong Yongmin; Chu Yonglie; Wang Zhilun

    2006-01-01

    Objective To investigate the relationship between erythrocyte immune function and selenium (Se)level. Methods Forty-nine Kashin-Beck patients in endemic area aged 13- 16 years were divided into two groups and were orally given either selenized yeast or sodium selenite to provide 200 μg selenium per day for 12 weeks. Erythrocyte selenium level, glutathione peroxidase activity, the rosette formation rates of red blood cells complement receptor type Ⅰ(CR1), the immune function of red blood cells, and circulating immune complexes(CIC) were determined. Results After supplementing with selenium for 12 weeks, erythrocyte selenium level, glutathione peroxidase activity, the rosette formation rates of red blood cells CR1 were significantly increased. But the difference in rosette formation rates of IC and CIC content was not significant between before and after Se supplementation. Conclusion The increase of the immune function of the erythrocyte by selenium-supplement may be one of the effective mechanisms for the prevention of Kashin-Beck disease.

  19. Self-statements, self-esteem, and locus of control in discriminating college students' scores on the Beck Depression Inventory.

    Science.gov (United States)

    Madonna, S; Philpot, V D

    1996-04-01

    To study the use of the ratio of positive to negative self-statements, locus of control, and self-esteem in discriminating between scores on the Beck Depression Inventory 145 undergraduate college students were administered the Beck Depression Inventory, Automatic Thoughts Questionnaire-Revised, Coopersmith Self-esteem Inventory-Adult Form, and the Rotter Locus of Control scale in their classrooms. A stepwise discriminant analysis indicated that five variables combined to yield a statistically significant discrimination among low, middle, and high scores on the Beck Depression Inventory. The classification analysis indicated that 77.1% (n = 111) of the undergraduate students were correctly classified; 93.2% (82 of 88) were correctly classified as low scorers and 73.3% (18 of 46) were correctly classified as high scorers. PMID:9148311

  20. Teoria da resposta ao item aplicada ao Inventário de Depressão Beck Item response theory applied to the Beck Depression Inventory

    Directory of Open Access Journals (Sweden)

    Stela Maris de Jezus Castro

    2010-09-01

    Full Text Available O Inventário de Depressão Beck (BDI, uma escala que mede o traço latente de intensidade de sintomas depressivos, pode ser avaliado através da Teoria da Resposta ao Item (TRI. Este estudo utilizou o modelo TRI de Resposta Gradual na avaliação da intensidade de sintomas depressivos de 4.025 indivíduos que responderam ao BDI, de modo a explorar eficientemente a informação disponível nos diferentes aspectos possibilitados pelo uso desta metodologia. O ajuste foi efetuado no software PARSCALE. Foram identificados 13 itens do BDI nos quais pelo menos uma categoria de resposta não tinha chance maior que as demais de ser escolhida, de modo que estes itens tiveram de ser recategorizados. Os itens com maior capacidade de discriminação são relativos à tristeza, pessimismo, sentimento de fracasso, insatisfação, auto-aversão, indecisão e dificuldade para trabalhar. Os itens mais graves são aqueles relacionados com perda de peso, retraimento social e idéias suicidas. O grupo dos 202 indivíduos com as maiores intensidades de sintomas depressivos foi composto por 74% de mulheres, e praticamente 84% possuíam diagnóstico de algum transtorno psiquiátrico. Os resultados evidenciam alguns dos inúmeros ganhos advindos da utilização da TRI na análise de traços latentes.The Beck Depression Inventory (BDI, a scale that measures the latent trait intensity of depression symptoms, can be assessed by the Item Response Theory (IRT. This study used the Graded-Response model (GRM to assess the intensity of depressive symptoms in 4,025 individuals who responded to the BDI, in order to efficiently use the information available on different aspects enabled by the use of this methodology. The fit of this model was done in PARSCALE software. We identified 13 items of the BDI in which at least one response category was not more likely than others to be chosen, so that these items had to be categorized again. The items with greater power of

  1. Ontario Hydro`s Sir Adam Beck Pump Generating Station : thrust bearing and runner servomotor rehabilitation

    Energy Technology Data Exchange (ETDEWEB)

    Barbour, J.; Garro, A. [Ontario Hydro, Toronto, ON (Canada)

    1998-12-01

    A study was conducted to examine the reasons for the recurring failure of generator thrust bearings at Ontario Hydro`s Sir Adam Beck Pump Generating Station (Niagara Falls) comprised of six 25 MW Deriaz turbines. The possible causes for the thrust bearing failures were listed and commented upon. The suspected causes include: (1) marginal bearing capacity, (2) shoes not flat, (3) sub standard oil, (4) dirt in bearing, (5) bearing cooling problems. To solve the problem, extra precaution was taken in the assembly of the bearing parts and extra capacity was added to the oil lift system. Following implementation of these measures, the unit has been operating smoothly for 3 years. 3 tabs., 4 figs.

  2. OCCURRENCE CHARACTERISTIC OF KASHIN-BECK DISEASE BASED ON NUCLEAR FAMILY PEDIGREES

    Institute of Scientific and Technical Information of China (English)

    郭雄; 杨亚宁

    2003-01-01

    Objective The occurrence characteristic of Kashin-Beck Disease (KBD) in pedigrees ascertained on the basis of one proband was estimated. Methods A total of 255 individuals in 40 pedigrees were collected from areas in the Shaanxi Province. Results ① Parents and siblings of index cases have a 3-4 times higher risk than a random unrelated individual. The odds ratio for disease is higher in mothers than in fathers of index cases; ② Prevalence in relatives of index cases (Kr=59.2%) greatly exceeds population prevalence (K=17.5%); ③ Kr increases with sibship size; ④ There is no significant difference of Kr for male and female siblings of index cases. Also, population prevalence is not sex-specific. Conclusion In conjunction with environmental agents, genetics may play an important role in KBD etiology.

  3. Arthroscopic Ankle Arthrodesis for Treating Osteoarthritis in a Patient with Kashin-Beck Disease

    Directory of Open Access Journals (Sweden)

    Kenjiro Iwasa

    2014-01-01

    Full Text Available Kashin-Beck disease (KBD is an endemic degenerative osteoarthritis. Death of cartilage and growth plate is the pathologic feature; therefore, KBD involves skeletal deformity and often results in osteoarthritis. Deficiency of selenium, high humic acid levels in water, and fungi on storage gains are considered the cause of KBD. The most frequently involved joints are ankles, knees, wrists, and elbows and symptoms are pain and limited motions of those joints. The main treatments for KBD are rehabilitation and osteotomy to correct the deformities because preventive treatment has not been established. In this report, we present a case of ankle osteoarthritis due to KBD and first describe arthroscopic ankle arthrodesis for treating osteoarthritis of KBD.

  4. Electronic structure of transparent oxides with the Tran-Blaha modified Becke-Johnson potential.

    Science.gov (United States)

    Dixit, H; Saniz, R; Cottenier, S; Lamoen, D; Partoens, B

    2012-05-23

    We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. We studied the basic n-type conducting binary oxides In(2)O(3), ZnO, CdO and SnO(2) along with the p-type conducting ternary oxides delafossite CuXO(2) (X=Al, Ga, In) and spinel ZnX(2)O(4) (X=Co, Rh, Ir). The results are presented for calculated band gaps and effective electron masses. We discuss the improvements in the band gap determination using TB-mBJ compared to the standard generalized gradient approximation (GGA) in density functional theory (DFT) and also compare the electronic band structure with available results from the quasiparticle GW method. It is shown that the calculated band gaps compare well with the experimental and GW results, although the electron effective mass is generally overestimated. PMID:22538303

  5. BECK FOUMULA REVISION FOR 222Rn ESCAPE AND WATER CONTENT IN SOIL

    Institute of Scientific and Technical Information of China (English)

    姜让荣; 卢兆伦; 等

    1995-01-01

    This paper points out the limitation of Beck formula and gives a revised formula owing to the water content and 222Rn escape in soil for calculating γ radiation dose rate through the experimental fitting from 576 sets of measured values in Zhejiang Province,When the revised formula is applied to Beijing Municipality,wherer there is a great difference in the meteorology and soil conditions,the calculated average in general is only 3.5% different from that measured;those of every position deviate only2.1% averagely;and their dispersion is in the experimental errors.Therefore,the revised formula possesses a high reliability and a broad suitability,and is an effective method to estimate the γ radiation dose rate onb the land.

  6. Internet Addiction and Beck Depression Inventory in the University Students at a Student Hostel

    Directory of Open Access Journals (Sweden)

    Atilla Senih Mayda 1

    2015-03-01

    Full Text Available Objective: To determine the relationship between internet addiction and depression in students at a student hostel. Methods: The data of this descriptive study was collected with questionnaires applied to 698 of 1000 university students by face to face interview. Data was collected with Beck Depression Inventory and with the interview form that includes 15 questions about sociodemographic characteristics and 7 questions they were prepared using Goldberg’s diagnostic criteria. Results: Among the participants 397 (56,9% were diagnosed as Internet addicts. 61,4% of men and 51,6 %of women were internet addicts and the difference was significant (x²=6.90, p=0.009. Internet addiction was higher in the group over and at the age 19, then the group under 19 years (x2=5.07, p=0,024. 194 (80,5% of 241students they have 18 points and higher by Beck Depression Inventory were in the internet addicts group. Although 203 (44.4% of 457 students they have 17 points and lower were prone to depression. BDI points were higher by the students they had chronic illness and they were to fail. Conclusion: According to BDI, internet addiction is most common by students they are prone to depression. The tendency to depression can be a cause or a consequent of internet addiction. Depression is not only associated with internet addiction. It can be related with chronic illness, losing relatives in the past year, satisfaction by faculty, school failure, and parents to be alive and together. Thus it must be researched if these are independent related with depression.

  7. Cross-Cultural Validation of the Beck Depression Inventory-II across U.S. and Turkish Samples

    Science.gov (United States)

    Canel-Cinarbas, Deniz; Cui, Ying; Lauridsen, Erica

    2011-01-01

    The purpose of this study was to test the Beck Depression Inventory-II (BDI-II) for factorial invariance across Turkish and U.S. college student samples. The results indicated that (a) a two-factor model has an adequate fit for both samples, thus providing evidence of configural invariance, and (b) there is a metric invariance but "no" sufficient…

  8. Analysis of selenium content in hair samples of children in Kaschin-Beck Disease areas in Gansu Province

    Institute of Scientific and Technical Information of China (English)

    康芬艳

    2013-01-01

    Objective To compare selenium content in hair samples of children in Kashin-Beck Disease (KBD) areas and control areas,and to provide academic data for KBD control and prevention.Methods In 2011,Longnan,Qingyang,Dingxi City of KDB areas in Gansu Province were selected as survey point,meanwhile,colleagues of Tianshui City and Lanzhou City were selected as control.

  9. Self-Concepts and Psychological Well-Being Assessed by Beck Youth Inventory among Pupils with Reading Difficulties

    Science.gov (United States)

    Lindeblad, Emma; Svensson, Idor; Gustafson, Stefan

    2016-01-01

    This study investigated the self-image and psychological well-being in 67 children and adolescents age 10-16 years with severe reading difficulties and/or dyslexia. The participants were assessed with Beck Youth Inventory regarding symptoms of depression, anxiety, and negative self-image. The results showed that the participants do not depict…

  10. Psychometric Properties of the Chinese Version of the Beck Depression Inventory-II Using the Rasch Model

    Science.gov (United States)

    Wu, Pei-Chen; Chang, Lily

    2008-01-01

    The authors investigated the Chinese version of the Beck Depression Inventory-II (BDI-II-C; Chinese Behavioral Science Corporation, 2000) within the Rasch framework in terms of dimensionality, item difficulty, and category functioning. Two underlying scale dimensions, relatively high item difficulties, and a need for collapsing 2 response…

  11. The Beck depression inventory as a measure of subjective well-being : A cross-national study

    NARCIS (Netherlands)

    van Hemert, D.A.; van de Vijver, F.J.R.; Poortinga, Y.H.

    2002-01-01

    The present study examined the question whether the Beck Depression Inventory (BDI), which is one of the most widely used instruments to assess depression, can be used to measure differences in subjective well-being at national level. In order to establish the meaning of depression scores at country

  12. Exploring the Old Town School of Folk Music's Beck "Song Reader" Ensemble: An Interview with Nathaniel Braddock

    Science.gov (United States)

    Thibeault, Matthew D.

    2014-01-01

    This column presents an interview with Nathaniel Braddock, who created and teaches an ensemble devoted to Beck's "Song Reader" at the Old Town School of Folk Music in Chicago, Illinois. "Song Reader" is a collection of 20 compositions published as sheet music for musicians to record and release, with over 17,000 versions…

  13. Correlação entre Inventário de Depressão de Beck e cortisol urinário em diabéticos tipo 2 Correlación entre el inventario de Depresión de Beck y el cortisol urinario en diabeticos tipo 2 Correlation between urine cortisol and scores on the Beck Depression inventory in patients with type 2 diabetes

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    Alexandra Bulgarelli do Nascimento

    2009-01-01

    Full Text Available OBJETIVO: Verificar a correlação entre o cortisol urinário e o Inventário de Depressão de Beck em diabéticos do tipo 2. MÉTODOS: O cortisol urinário foi avaliado em uma amostra composta por 40 pacientes da Liga de Controle de Diabetes da Disciplina de Endocrinologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo e para a avaliação dos sintomas de depressão foi aplicado o Inventário de Depressão de Beck. RESULTADOS: Alta confiabilidade para o Inventário de Depressão de Beck(Alfa de Cronbach=0,920e correlação significativa foi observada entre cortisol urinário e Inventário de Depressão de Beck(Spearman,r=0.523,pOBJETIVO: Verificar la correlación entre el cortisol urinario y el Inventario de Depresión de Beck en diabéticos del tipo 2. MÉTODOS: El cortisol urinario fue evaluado en una muestra compuesta por 40 pacientes de la Liga de Control de Diabetes de la Disciplina de Endocrinología del Hospital de las Clínicas de la Facultad de Medicina de la Universidad de Sao Paulo y para la evaluación de los síntomas de depresión fue aplicado el Inventario de Depresión de Beck. RESULTADOS: Alta confiabilidad para el Inventario de Depresión de Beck(Alfa de Cronbach=0,920 y correlación significativa observada entre el cortisol urinario e Inventario de Depresión de Beck (Spearman,r=0.523,pOBJECTIVE: To determine the relationship between urinary cortisol and scores on the Beck Depression Inventory in type 2 diabetics. METHODS: The sample consisted of 40 patients with type 2 diabetes from the diabetes control league of the discipline of endocrinology of the HCFM-USP. Measures consisted of urinary cortisol and depression symptoms using the Beck Depression Inventory. RESULTS: The Beck Depression Inventory had a Cronbach's alpha of 0.92. There was a statistically significant correlation between urinary cortisol and scores on the Beck Depression Inventory (Spearman r = 0.52, p < .001. CONCLUSIONS: The

  14. Profiling modern risks. An appraisal of the works of bauman, beck, castel, giddens and baudrillard

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    Korstanje Maximiliano

    2010-12-01

    Full Text Available Undoubtedly, the fear can be seen a grounding emotion broadly studied by psychology, sociology and anthropology for many years. Every end of millennium represents for human beings a new embodiment of their beliefs, their production, forms of consumption and even their hierarchical lines of authority. As privileged witnesses of the starting of a new millennium, one might realize how the sentiment of unprotection has been disseminated as a virus world-wide. Ranging from appalling events such as 11/09 towards the Swine Flu recently appeared in Mexico, the perception of lay-people of what is or not dangerous seem to be changed for-ever. Under such a context, the present theoretical manuscript explores the connection of risk and fear at the time it delves into the main contributions and limitations of Jean Baudrillard, Anthony Giddens, Robert Castel, Ulrich Beck and Zygmunt Bauman. From different angles, every-one of cited scholars will give to reader an insight view of the role played by risk and fear in our modern society.

  15. Sub-tangentially loaded and damped Beck's columns on two-parameter elastic foundation

    Science.gov (United States)

    Lee, Jun-Seok; Kim, Nam-Il; Kim, Moon-Young

    2007-10-01

    The dynamic stability of the damped Beck's column on two-parameter elastic foundation is investigated by using Hermitian beam elements. For this purpose, based on the extended Hamilton's principle, the dimensionless finite element (FE) formulation using the Hermitian interpolation function is presented. First, the mass matrix, the external and internal damping matrices, the elastic and the geometric stiffness matrices, Winkler and Pasternak foundation matrices, and the load correction stiffness matrix due to the sub-tangential follower force are obtained. Then, evaluation procedure for the flutter and divergence loads of the non-conservative system and the time history analysis using the Newmark- β method are shortly described. Finally, the influences of various parameters on the dynamic stability of non-conservative systems are newly addressed: (1) variation of the second flutter load due to sub-tangentiality, (2) influences of the external and the internal damping on flutter loads by analysis of complex natural frequencies, (3) the effect of the growth rate of motion in a finite time interval using time history analysis, and (4) fluctuation of divergence and flutter loads due to Winkler and Pasternak foundations.

  16. Psychometric Properties of the Persian Version of the Short Beck Depression Inventory with Iranian Psychiatric Outpatients.

    Science.gov (United States)

    Dadfar, Mahboubeh; Kalibatseva, Zornitsa

    2016-01-01

    The short form of the Beck Depression Inventory (BDI-13) is useful for the screening and assessment of depression in clinical and research settings. The aim of the present study was to investigate the psychometric properties of the Persian (Farsi) version of BDI-13 in an Iranian clinical sample. The sample consisted of 52 Iranian psychiatric outpatients who received services at psychiatric and psychological clinics at the School of Behavioral Sciences & Mental Health-Tehran Institute of Psychiatry, Iran University of Medical Sciences (IUMS) in Tehran, Iran. The study examined the reliability, construct validity, and factor structure of the instrument. The instrument indicated good reliability with Cronbach's alpha of .85 and strong construct validity based on moderate to strong positive correlations with other measures of mental health issues. Using a Principal Component Analysis and Varimax Rotation with Kaiser Normalization, three factors were identified and labeled Affective (F1), Somatic/Vegetative (F2), and Cognitive/Loss of Functioning (F3). The current factor structure suggests that depression is a multidimensional construct in an Iranian clinical sample. This study provides further evidence that the Persian version of the BDI-13 is a psychometrically sound instrument that can be used for clinical and research purposes in Iran. PMID:27293979

  17. Modified Becke-Johnson exchange potential: improved modeling of lead halides for solar cell applications

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    Radi A. Jishi

    2016-01-01

    Full Text Available We report first-principles calculations, within density functional theory, on the lead halide compounds PbCl2, PbBr2, and CH3NH3PbBr3−xClx, taking into account spin-orbit coupling. We show that, when the modified Becke-Johnson exchange potential is used with a suitable choice of defining parameters, excellent agreement between calculations and experiment is obtained. The computational model is then used to study the effect of replacing the methylammonium cation in CH3NH3PbI3 and CH3NH3PbBr3 with either N2H5+or N2H3+, which have slightly smaller ionic radii than methylammonium. We predict that a considerable downshift in the values of the band gaps occurs with this replacement. The resulting compounds would extend optical absorption down to the near-infrared region, creating excellent light harvesters for solar cells.

  18. The latent symptom structure of the Beck depression inventory: second edition in Latina pregnant women.

    Science.gov (United States)

    Alexander, Lisa A; de la Fey Rodríguez Muñoz, Maria; Perry, Deborah F; Le, Huynh-Nhu

    2014-07-01

    Pregnancy represents a unique period of time when women are at an increased risk of developing depression. Although the Beck Depression Inventory-Second Edition (BDI-II) is one of the most widely used self-report measures of depression symptomology, its psychometric properties and underlying factor structures have not been determined for antenatal women and among Latinas. The current study evaluated the latent symptom structure of the BDI-II in a community-based sample of Latina pregnant women (N = 217) identified to be at high risk for depression. Exploratory factor analyses were used to identify underlying salient individual item loadings for two- and three-factor models. Confirmatory factor analyses then examined several different indices to determine the best model fit. Examination of exploratory and confirmatory factor analyses supports a three-factor oblique structure of the BDI-II composed of Cognitive-Affective, Somatic, and Pregnancy Symptoms. The three-factor model provides clinicians with the ability to target specific constellations of depressive symptoms instead of relying on the BDI-II total score that represents the overall severity of depression in this population. PMID:23929560

  19. Does the Beck Cognitive Insight Scale Predict Response to Cognitive Remediation in Schizophrenia?

    Science.gov (United States)

    Harvey, Philippe-Olivier

    2016-01-01

    Cognitive remediation therapy (CRT) has emerged as a viable treatment option for people diagnosed with schizophrenia presenting disabling cognitive deficits. However, it is important to determine which variables can influence response to CRT in order to provide cost-effective treatment. This study's aim was to explore cognitive insight as a potential predictor of cognitive improvement after CRT. Twenty patients with schizophrenia completed a 24-session CRT program involving 18 hours of computer exercises and 6 hours of group discussion to encourage generalization of cognitive training to everyday activities. Pre- and posttest assessments included the CogState Research Battery and the Beck Cognitive Insight Scale (BCIS). Lower self-certainty on the BCIS at baseline was associated with greater improvement in speed of processing (rs = −0.48; p < 0.05) and visual memory (rs = −0.46; p < 0.05). The results of this study point out potential associations between self-certainty and cognitive improvement after CRT, a variable that can easily be measured in clinical settings to help evaluate which patients may benefit most from the intervention. They also underline the need to keep investigating the predictors of good CRT outcomes, which can vary widely between patients. PMID:27516906

  20. Does the Beck Cognitive Insight Scale Predict Response to Cognitive Remediation in Schizophrenia?

    Directory of Open Access Journals (Sweden)

    Audrey Benoit

    2016-01-01

    Full Text Available Cognitive remediation therapy (CRT has emerged as a viable treatment option for people diagnosed with schizophrenia presenting disabling cognitive deficits. However, it is important to determine which variables can influence response to CRT in order to provide cost-effective treatment. This study’s aim was to explore cognitive insight as a potential predictor of cognitive improvement after CRT. Twenty patients with schizophrenia completed a 24-session CRT program involving 18 hours of computer exercises and 6 hours of group discussion to encourage generalization of cognitive training to everyday activities. Pre- and posttest assessments included the CogState Research Battery and the Beck Cognitive Insight Scale (BCIS. Lower self-certainty on the BCIS at baseline was associated with greater improvement in speed of processing (rs=-0.48; p<0.05 and visual memory (rs=-0.46; p<0.05. The results of this study point out potential associations between self-certainty and cognitive improvement after CRT, a variable that can easily be measured in clinical settings to help evaluate which patients may benefit most from the intervention. They also underline the need to keep investigating the predictors of good CRT outcomes, which can vary widely between patients.

  1. A generalized Grubbs-Beck test statistic for detecting multiple potentially influential low outliers in flood series

    Science.gov (United States)

    Cohn, T.A.; England, J.F.; Berenbrock, C.E.; Mason, R.R.; Stedinger, J.R.; Lamontagne, J.R.

    2013-01-01

    he Grubbs-Beck test is recommended by the federal guidelines for detection of low outliers in flood flow frequency computation in the United States. This paper presents a generalization of the Grubbs-Beck test for normal data (similar to the Rosner (1983) test; see also Spencer and McCuen (1996)) that can provide a consistent standard for identifying multiple potentially influential low flows. In cases where low outliers have been identified, they can be represented as “less-than” values, and a frequency distribution can be developed using censored-data statistical techniques, such as the Expected Moments Algorithm. This approach can improve the fit of the right-hand tail of a frequency distribution and provide protection from lack-of-fit due to unimportant but potentially influential low flows (PILFs) in a flood series, thus making the flood frequency analysis procedure more robust.

  2. Prevalence of depression and its associated factors using Beck Depression Inventory among students of a medical college in Karnataka

    OpenAIRE

    Kumar, Ganesh S; Jain, Animesh; Hegde, Supriya

    2012-01-01

    Background and Objective: Depression among medical students is an area of increasing concern worldwide. This study aimed to assess the prevalence of depression and its associated factors among medical students. Materials and Methods: A stratified random sample of 400 students was assessed using Beck Depression Inventory by investigators. Associations between depression and class of studying, social factors like alcohol use, drug addiction, family problems, family history of depression, and st...

  3. Biological reduction of iron to the elemental state from ochre deposits of Skelton Beck in Northeast England

    OpenAIRE

    Rahman, Pattanathu K. S. M.; Bastola, Suvechhya

    2014-01-01

    Ochre, consequence of acid mine drainage (AMD), is iron oxides-rich soil pigments that can be found in the water drainage from historic base metal and coal mines. The anaerobic strains of Geobacter sulfurreducens and Shewanella denitrificans were used for the microbial reduction of iron from samples of ochre collected from Skelton Beck (Saltburn Orange River, NZ 66738 21588) in Northeast England. The aim of the research was to determine the ability of the two anaerobic bacteria to reduce the ...

  4. Biological reduction of iron to the elemental state from ochre deposits of Skelton Beck in Northeast England

    OpenAIRE

    PattanathuK S MRahman

    2014-01-01

    Ochre, consequence of acid mine drainage, is iron oxides-rich soil pigments that can be found in the water drainage from historic base metal and coal mines. The anaerobic strains of Geobacter sulfurreducens and Shewanella denitrificans were used for the microbial reduction of iron from samples of ochre collected from Skelton Beck (Saltburn Orange River, NZ 66738 21588) in Northeast England. The aim of the research was to determine the ability of the two anaerobic bacteria to reduce the iron p...

  5. Dimensional and hierarchical models of depression using the Beck Depression Inventory-II in an Arab college student sample

    OpenAIRE

    Ohaeri Jude U; Al-Turkait Fawziyah A

    2010-01-01

    Abstract Background An understanding of depressive symptomatology from the perspective of confirmatory factor analysis (CFA) could facilitate valid and interpretable comparisons across cultures. The objectives of the study were: (i) using the responses of a sample of Arab college students to the Beck Depression Inventory (BDI-II) in CFA, to compare the "goodness of fit" indices of the original dimensional three-and two-factor first-order models, and their modifications, with the corresponding...

  6. Funcionamento Diferencial do Item no Inventário de Depressão Beck

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    Stela Maris de Jezus Castro

    2015-03-01

    Full Text Available INTRODUÇÃO: Diversos estudos mostram o Funcionamento Diferencial do Item (DIF em itens do Inventário de Depressão Beck (BDI, ao compararem homens e mulheres. A presença de um grande número de itens com DIF no BDI é uma severa ameaça à validade da medida da intensidade de sintomas depressivos obtida pela Teoria da Resposta ao Item (TRI e às conclusões baseadas nos escores derivados dos itens com e sem DIF. OBJETIVO: Os objetivos deste estudo foram identificar esses itens do BDI, ajustar o modelo de TRI para itens constrangedores (modelo 2, o qual acomoda itens com a presença de DIF, e comparar esses resultados com os do ajuste do modelo logístico de dois parâmetros tradicional da TRI (modelo 1. MÉTODOS: Os resultados obtidos com ambos os modelos foram comparados. RESULTADOS: Os itens que apresentaram DIF foram: tristeza, sentimento de fracasso, insatisfações, culpa, punição, choro, fatigabilidade e perda da libido. Os resultados do ajuste dos dois modelos são similares quanto à discriminação, gravidade (à exceção dos itens com DIF e no cálculo de escores para os indivíduos. Apesar disso, o modelo 2 é vantajoso, pois mostra as diferenças em gravidade do sintoma depressivo para os grupos avaliados, trazendo, dessa forma, mais informação ao pesquisador sobre a população estudada. CONCLUSÃO: Esse modelo, que tem um alcance mais amplo em termos de população-alvo, pode ser uma ótima alternativa na identificação e acompanhamento de indivíduos com potencial depressivo.

  7. Disordered glycometabolism involved in pathogenesis of Kashin–Beck disease, an endemic osteoarthritis in China

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Cuiyan, E-mail: xj.cy.69@stu.xjtu.edu.cn [School of Public Health, Health Science Centre of Xi' an Jiaotong University, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education (China); Key Laboratory of Trace elements and Endemic Diseases, Ministry of Health, Xi' an, Shaanxi 710061 (China); Lei, Ronghui, E-mail: leirh@mail.xjtu.edu.cn [School of Public Health, Health Science Centre of Xi' an Jiaotong University, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education (China); Key Laboratory of Trace elements and Endemic Diseases, Ministry of Health, Xi' an, Shaanxi 710061 (China); Tiainen, Mika, E-mail: mika.tiainen@uef.fi [School of Pharmacy, University of Eastern Finland, Kuopio (Finland); Wu, Shixun, E-mail: wushixun313@stu.xjtu.edu.cn [School of Public Health, Health Science Centre of Xi' an Jiaotong University, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education (China); Key Laboratory of Trace elements and Endemic Diseases, Ministry of Health, Xi' an, Shaanxi 710061 (China); Zhang, Qiang, E-mail: wdrr@163.com [Department of Kashin–Beck Disease, Qinghai Institute for Endemic Disease Control and Prevention, Xining, Qinghai 811602 (China); Pei, Fuxing, E-mail: peifuxing@vip.163.com [Department of Orthopedics, West China Hospital, Sichuan University, Chengdu, Sichuan 610041 (China); Guo, Xiong, E-mail: guox@mail.xjtu.edu.cn [School of Public Health, Health Science Centre of Xi' an Jiaotong University, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education (China); Key Laboratory of Trace elements and Endemic Diseases, Ministry of Health, Xi' an, Shaanxi 710061 (China)

    2014-08-15

    Kashin–Beck disease (KBD) is a chronic endemic osteoarthritis in China. Previous studies have suggested a role of metabolic dysfunction in causation of this disease. In this investigation, the metabolomics approach and cell experiments were used to discover the metabolic changes and their effects on KBD chondrocytes. Nuclear magnetic resonance ({sup 1}H NMR) spectroscopy was used to examine serum samples from both the KBD patients and normal controls. The pattern recognition multivariate analysis (OSC–PLS) and quantitative analysis (QMTLS iterator) revealed altered glycometabolism in KBD, with increased glucose and decreased lactate and citrate levels. IPA biological analysis showed the centric location of glucose in the metabolic network. Massive glycogen deposits in chondrocytes and increased uptake of glucose by chondrocytes further confirmed disordered glycometabolism in KBD. An in vitro study showed the effects of disordered glycometabolism in chondrocytes. When chondrocytes were treated with high glucose, expression of type II collagen and aggrecan were decreased, while TNF-α expression, the level of cellular reactive oxygen species and cell apoptosis rates all were increased. Therefore, our results demonstrated that disordered glycometabolism in patients with KBD was linked to the damage of chondrocytes. This may provide a new basis for understanding the pathogenesis of KBD. - Highlights: • Disordered glycometabolism in KBD was demonstrated by combining serum metabolomics and chondrocyte studies. • Glucose and TNF-α were key molecules linked to altered metabolism and inflammation in the pathophysiology of KBD. • The glycometabolism disorder was linked to expression of type II collagen and aggrecan, ROS and apoptosis of KBD chondrocytes.

  8. Aaron Temkin BECK: After Cricitical Thinking to A Creative Psychotherapy Theory

    Directory of Open Access Journals (Sweden)

    Mehmet DİNÇ

    2012-07-01

    Full Text Available There is growing interest in the cognitive psychotherapy all around the world including Turkey. According to American Institute of Cognitive Therapy; cognitive psychotherapy is the fastest growing and most rigorously studied kind of talk therapy and it is practiced around the world, taking hold in places from the Middle East to Japan. Cognitive psychotherapy was designed first by Aaron Temkin Beck in 1950’s. He has published over 450 articles and authored or co-authored seventeen books and he has been listed as one of the “10 individuals who shaped the face of American Psychiatry” and one of the 5 most influential psychotherapists of all time since then. Beck’s groundbreaking systematic research established for the first time the efficacy of any psychotherapy for the treatment of depression. Moreover he not only developed and tested an effective short-term treatment (cognitive therapy for depression, but he and his former students have successfully adapted cognitive therapy to a wide range of other psychiatric disorders as well. Numerous controlled clinical trials have now demonstrated that cognitive therapy is effective in a variety of psychiatric conditions including depression, bulimia nervosa, hypochondriasis, social phobia, obsessive-compulsive disorder, substance abuse, body dysmorphic disorder, and post-traumatic stress disorder. Therefore knowing the father of cognitive therapy and his journey from 1950’s to 2010’s will help to understand cognitive therapy and its development during these years. This article aims to give an overview of the historical background to contemporary cognitive and cognitive-behavioral approaches to psychotherapy by focusing on Beck’s life, characteristics and works.

  9. Robust flood frequency analysis: Performance of EMA with multiple Grubbs-Beck outlier tests

    Science.gov (United States)

    Lamontagne, J. R.; Stedinger, J. R.; Yu, Xin; Whealton, C. A.; Xu, Ziyao

    2016-04-01

    Flood frequency analysis generally involves the use of simple parametric probability distributions to smooth and extrapolate the information provided by short flood records to estimate extreme flood flow quantiles. Parametric probability distributions can have difficulty simultaneously fitting both the largest and smallest floods. A danger is that the smallest observations in a record can distort the exceedance probabilities assigned to the large floods of interest. The identification and treatment of such Potentially Influential Low Floods (PILFs) frees a fitting algorithm to describe the distribution of the larger observations. This can allow parametric flood frequency analysis to be both efficient, and also robust to deviations from the proposed probability model's lower tail. Historically, PILF identification involved subjective judgement. We propose a new multiple Grubbs-Beck outlier test (MGBT) for objective PILF identification. MGBT PILF identification rates (akin to Type I errors) are reported for the lognormal (LN) distribution and the log-Pearson Type III (LP3) distribution with a variety of skew coefficients. MGBT PILF identification generally matched subjective identification from a recent California flood frequency study. Monte Carlo results show that censoring of PILFs identified by the MGBT algorithm improves the extreme quantile estimator efficiency of the expected moments algorithm (EMA) for negatively skewed LP3 distributions and has little effect for zero or positive skews; simultaneously it protects against deviations from the LP3 in the lower tail, as illustrated by distorted LN examples. Thus, MGBT generally makes flood frequency analysis based on the LP3 distribution with EMA both more accurate and more robust.

  10. Disordered glycometabolism involved in pathogenesis of Kashin–Beck disease, an endemic osteoarthritis in China

    International Nuclear Information System (INIS)

    Kashin–Beck disease (KBD) is a chronic endemic osteoarthritis in China. Previous studies have suggested a role of metabolic dysfunction in causation of this disease. In this investigation, the metabolomics approach and cell experiments were used to discover the metabolic changes and their effects on KBD chondrocytes. Nuclear magnetic resonance (1H NMR) spectroscopy was used to examine serum samples from both the KBD patients and normal controls. The pattern recognition multivariate analysis (OSC–PLS) and quantitative analysis (QMTLS iterator) revealed altered glycometabolism in KBD, with increased glucose and decreased lactate and citrate levels. IPA biological analysis showed the centric location of glucose in the metabolic network. Massive glycogen deposits in chondrocytes and increased uptake of glucose by chondrocytes further confirmed disordered glycometabolism in KBD. An in vitro study showed the effects of disordered glycometabolism in chondrocytes. When chondrocytes were treated with high glucose, expression of type II collagen and aggrecan were decreased, while TNF-α expression, the level of cellular reactive oxygen species and cell apoptosis rates all were increased. Therefore, our results demonstrated that disordered glycometabolism in patients with KBD was linked to the damage of chondrocytes. This may provide a new basis for understanding the pathogenesis of KBD. - Highlights: • Disordered glycometabolism in KBD was demonstrated by combining serum metabolomics and chondrocyte studies. • Glucose and TNF-α were key molecules linked to altered metabolism and inflammation in the pathophysiology of KBD. • The glycometabolism disorder was linked to expression of type II collagen and aggrecan, ROS and apoptosis of KBD chondrocytes

  11. Whole-exome sequencing for the identification of susceptibility genes of Kashin-Beck disease.

    Directory of Open Access Journals (Sweden)

    Zhenxing Yang

    Full Text Available OBJECTIVE: To identify and investigate the susceptibility genes of Kashin-Beck disease (KBD in Chinese population. METHODS: Whole-exome capturing and sequencing technology was used for the detection of genetic variations in 19 individuals from six families with high incidence of KBD. A total of 44 polymorphisms from 41 genes were genotyped from a total of 144 cases and 144 controls by using MassARRAY under the standard protocol from Sequenom. Association was applied on the data by using PLINK1.07. RESULTS: In the sequencing stage, each sample showed approximately 70-fold coverage, thus covering more than 99% of the target regions. Among the single nucleotide polymorphisms (SNPs used in the transmission disequilibrium test, 108 had a p-value of <0.01, whereas 1056 had a p-value of <0.05. Kyoto Encyclopedia of Genes and Genomes(KEGG pathway analysis indicates that these SNPs focus on three major pathways: regulation of actin cytoskeleton, focal adhesion, and metabolic pathways. In the validation stage, single locus effects revealed that two of these polymorphisms (rs7745040 and rs9275295 in the human leukocyte antigen (HLA-DRB1 gene and one polymorphism (rs9473132 in CD2-associated protein (CD2AP gene have a significant statistical association with KBD. CONCLUSIONS: HLA-DRB1 and CD2AP gene were identified to be among the susceptibility genes of KBD, thus supporting the role of the autoimmune response in KBD and the possibility of shared etiology between osteoarthritis, rheumatoid arthritis, and KBD.

  12. Psychometric characteristics of the Beck depression inventory on a Serbian student sample

    Directory of Open Access Journals (Sweden)

    Novović Zdenka

    2011-01-01

    Full Text Available Beck Depression Inventory (BDI is one of the most popular instruments for measuring intensity and symptoms of depression in clinical and general population. The instrument has been translated into many languages and validated in many different cultures, but there is still no published paper on psychometric characteristics and the norms for the BDI in Serbian language. In this paper, we checked psychometric characteristics of the BDI-II on 400 students of the University of Novi Sad, Serbia. Descriptive statistics (M=8.02; SD=7.10, internal consistency (α=.87, and test-retest reliability (.63 are satisfactory and similar to the results of other validation studies. Convergent and divergent validity of the instrument are also supported by moderate to high correlations with the measures of similar phenomena (r=.70 with Depression Symptoms Scale and by low correlations with unrelated constructs (i.e., r=.19 with Impulsive Sensation Seeking Scale. However, the divergent validity is not supported by a high correlation with a measure of anxiety (r=.70, similar finding is commonly obtained in other validation studies. Our results suggest cut-off scores which are similar to those suggested by Canadian authors (Kappa coefficient=.85. Two-factor structure of the inventory is also in concordance with other authors. Cognitive-Affective factor explains 29.27% of the variance and its structure resembles those reported in other analyses. The second extracted factor explains 7.76% of the variance and is saturated mostly with somatic items; however, a significant contribution of some cognitive items has led us to identify the factor as Exhaustion, specific to our student sample. The two-factor solution is confirmed by Confirmatory Factor Analyses once the item related to sexual difficulties was eliminated. General conclusion is that BDI-II has satisfactory psychometric characteristics and can reliably be used with Serbian student population.

  13. Hair Selenium Levels of School Children in Kashin-Beck Disease Endemic Areas in Tibet, China.

    Science.gov (United States)

    Chen, Zhuo; Li, Hairong; Yang, Linsheng; Wang, Wuyi; Li, Yonghua; Gong, Hongqiang; Guo, Min; Nima, Cangjue; Zhao, Shengcheng; Wang, Jing; Ye, Bixiong; Danzeng, Sangbu; Deji, Yangzong

    2015-11-01

    Previous studies have shown that the selenium (Se) deficiency is an important factor for the etiology of Kashin-Beck disease (KBD). Although KBD is presently controlled in most regions of China, it is still active in the Tibetan Plateau. The present study aimed to assess the nutritional status of selenium in school children by using the Se level in hair as a biomarker in KBD endemic areas of Lhasa in Tibet, China. Hair samples of 155 school children aged 6-15 years were collected in both KBD areas and non-KBD areas of Lhasa in 2013. The Se level in the hair samples was determined by inductive coupled plasma mass spectrometry (ICP-MS). The average concentration of Se in children's hair was 0.232 μg/g in KBD areas of Lhasa, which was significantly higher than the data reported decades ago. A significant difference in hair Se was observed between the boys (0.255 μg/g) and the girls (0.222 μg/g) in the studied KBD areas (P hair Se did not vary by age or region. School children in KBD endemic areas in Lhasa likely have improved Se status as a result of high Se content staple food substitution with the enforcement of Free Education Policy and Nutrition Improvement Plan in Tibet. Nevertheless, there were still 20.3 % of students with low Se status (hair Se <0.20 μg/g), which showed that Se status of school children was also partly affected by low Se environment in KBD endemic areas of Lhasa.

  14. THE PROSPECTIVE STUDY OF RELATIONSHIP BETWEEN LOW SELENIUM AND KASHIN-BECK DISEASE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The relationship of cause-result between low selenium (Se) and Kashin-Beck disease (KBD) was probed by the prospective study of epidemiological method with regarding low-Se as an exposure factor in this paper. 597 healthy children lived in KBD areas with low, middle and high prevalence were divided into the low-Se exposed group and the non-low-Se exposed group according to their Se content in hair. The low-Se exposed group was divided into three subgroups, such as Se content in hair≤110 ng/g, 110 ng/g<Se content in hair≤150 ng/g and 150 ng/g<Se content in hair≤200 ng/g, respectively. Six new cases of the total with KBD (incidence was 0.574% person-year) were found in the low-Se exposed group during three years period of the investigation. No new case was found in the non low-Se exposed group . KBD incidence was not significantly different between those two groups. Two new cases were found in children with Se content in hair kept below 110 ng/g during three years (incidence: 1.21% person-year). SMR in each group indicated that the new cases observed in the low-Se exposed group was remarkable lower than the new cases expected. It was not observed that the dose-response relationship between low-Se and KBD, and was not supported that the low-Se was a predominant factor to cause KBD.

  15. Criterion Validity, Severity Cut Scores, and Test-Retest Reliability of the Beck Depression Inventory-II in a University Counseling Center Sample

    Science.gov (United States)

    Sprinkle, Stephen D.; Lurie, Daphne; Insko, Stephanie L.; Atkinson, George; Jones, George L.; Logan, Arthur R.; Bissada, Nancy N.

    2002-01-01

    The criterion validity of the Beck Depression Inventory-II (BDI-II; A. T. Beck, R. A. Steer, & G. K. Brown, 1996) was investigated by pairing blind BDI-II administrations with the major depressive episode portion of the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I; M. B. First, R. L. Spitzer, M. Gibbon, & J. B. W. Williams,…

  16. The Beck Depression Inventory Second Edition (BDI-II): psychometric properties in Icelandic student and patient populations.

    Science.gov (United States)

    Arnarson, Thornorethur Orn; Olason, Daníel Thorn; Smári, Jakob; Sigurethsson, Jón Friethrik

    2008-01-01

    The Beck Depression Inventory (BDI) is one of the most widely used self-report measures of depression in both research and clinical practice. The Beck Depression Inventory Second Edition (BDI-II) is the most recent version of the BDI. The objective of the present study was to assess the psychometric foundations of the Icelandic translation of the BDI-II, adding to its international knowledge base. Participants were in total 1454, 1206 students and 248 outpatient-clinic patients. All students completed the BDI-II and a subgroup (n=142) completed additional measures of anxiety and depression. The Mini-International Psychiatric Interview (MINI) and the BDI-II were administrated to the patients. Convergent and divergent validity of the BDI-II were supported. It discriminated satisfactorily between patients diagnosed and those not diagnosed with major depression. Confirmatory factor analyses revealed small differences between various factor models of the BDI-II, derived from previous studies. However, a model of three first-order factors (cognitive-affective-somatic) and one second-order factor (general depression) offered an acceptable description of the item covariance structure for the BDI-II in both samples. It is concluded that the psychometric properties of the Icelandic version of the BDI-II are supported in patient and student populations. PMID:18752106

  17. STUDIES ON BLOOD GLUTATHIONE PEROXIDASE PROTEIN LEVEL OF CHILDREN IN KESHAN DISEASE AND KASHIN-BECK DISEASE AREAS

    Institute of Scientific and Technical Information of China (English)

    谭武红; 种晓红; 杨占田; 翟连榜; 王立新; 徐光禄

    2002-01-01

    Objective To oberve the change in blood glutathione peroxidase (GSH-Px) protein levels of residents in the low-selenium (Se) area by contrasting the blood GSH-Px protein level of the children in the Keshan disease area with those in the Kashin-Beck disease and non-endemic areas. Methods GSH-Px protein levels were measured by enzyme-linked immunosorbent assays (ELISA). The Se content and GSH-Px activity were assayed by the 2,3-diaminonaphthalene spectrofluorimetric method and glutathione reductase-coupled method respectively. Results ①The blood Se content and GSH-Px protein level of children in Keshan disease area (Moding) were significantly lower than those in Xi'an non-endemic area, however, there was no significant difference when compared with the low-Se non-endemic area; ②The blood Se content, GSH-Px activity and GSH-Px protein level of children in the Kashin-Beck disease area (Yulin) were significantly lower than those of children in two non-endemic areas and in the Keshan disease area; ③The blood Se content and GSH-Px activity were positively correlated to the GSH-Px protein level respectively. Conclusion These results indicate that the blood GSH-Px protein level is decreased in the low-Se residents. The Se status not only affects the GSH-Px activity but also regulate the GSH-Px protein level.

  18. Inventário de Depressão de Beck - BDI: validação fatorial para mulheres com câncer Beck Depression Inventory - BDI: factorial analysis for women with cancer

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Gandini

    2007-06-01

    Full Text Available Este estudo teve por objetivo validar fatorialmente o Inventário de Depressão de Beck - BDI para uma amostra de 208 mulheres com câncer. A validação fatorial do BDI foi realizada por meio da análise fatorial, método de extração dos componentes principais e rotação oblimin, tendo sido identificadas duas soluções fatoriais, uma bifatorial - sendo F1 composto por 8 itens (a = 0,82 denominado "visão negativa de si mesmo", explicando 32,4% da variância e F2 com 5 itens (a = 0,77 denominado "função física", explicando 8% da variância - e outra unifatorial com 13 itens, com fidedignidade altamente satisfatória (a = 0,86 denominada "depressão", explicando 38% da variância total.This study refers to the factor analysis of the Beck Depression Inventory - BDI in a population composed by 208 women with cancer. The extraction method was principal components and the rotation procedure was oblimin. The BDI factorial analysis was done through the oblimin rotation, finding two solutions possibilities. One with two factors solution - the first one with 8 items (a = 0,82, called "negative view of self", explaining 32,4% of the variance and the second factor with 5 items (a = 0,77, called "physical function", explaining 8% of the variance - and other with one factor solution with 13 items, with really satisfactory reliability of 0,86, called "depression" and explaining 38% of the total variance.

  19. O velho mundo novo do trabalho: concepção e abordagem em Ulrick Beck e Zygmunt Bauman

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    Luiz Carlos Chaves

    2006-01-01

    Full Text Available Este artigo tem por finalidade apresentar considerações delineadas por Beck e Bauman sobre o mundo do trabalho, problematizando as concepções e possibilidades apontadas por ambos. A hipótese de partida centra-se no argumento de que as constantes mudanças percebidas no mundo do trabalho, neste momento, ocorrem em decorrência de processos societais pretéritos e não propriamente em decorrência da vontade dos indivíduos. Entretanto, para se pensar a relação entre o mundo do trabalho e o indivíduo, na pós-modernidade, é imprescindível a leitura histórica dos aspectos sociais, psicológicos e fisiológicos do trabalho.

  20. [Antjekathrin Grassmann. Zu den wirtschaftlichen und persönlichen Beziehungen Lübecks ins Baltikum im Lichte einer unbeachteten mittelalterlichen Quellegruppe]/ Dennis Hortmuth

    Index Scriptorium Estoniae

    Hormuth, Dennis

    2012-01-01

    Arvustus: Antjekathrin Grassmann. Zu den wirtschaftlichen und persönlichen Beziehungen Lübecks ins Baltikum im Lichte einer unbeachteten mittelalterlichen Quellegruppe. In: Leder ist Brot. Beiträge zur norddeutschen Landes- und Archivgeseten. Schwerin 2011. S. 125-135

  1. Is the beck anxiety inventory a good tool to assess the severity of anxiety? A primary care study in The Netherlands study of depression and anxiety (NESDA)

    NARCIS (Netherlands)

    Muntingh, Anna D. T.; van der Feltz-Cornelis, Christina M.; van Marwijk, Harm W. J.; Spinhoven, Philip; Penninx, Brenda W. J. H.; van Balkom, Anton J. L. M.

    2011-01-01

    Background: Appropriate management of anxiety disorders in primary care requires clinical assessment and monitoring of the severity of the anxiety. This study focuses on the Beck Anxiety Inventory (BAI) as a severity indicator for anxiety in primary care patients with different anxiety disorders (so

  2. [Concurrent validation of the suicidal risk assessment scale (R.S.D.) with the Beck's suicidal ideation scale].

    Science.gov (United States)

    Ducher, J-L; Daléry, J

    2004-01-01

    The prevention of suicide is a top priority in mental health. The determination of high risk suicidal groups is not sufficient. The expressing suicidal ideas is not a protective factor, but in contrary a risk factor to take into account, or even to search and to quantify: 80% of the subjects who attempt to commit suicide or commit suicide express such ideas months before. Several evaluation instruments try to help the practitioners or the research workers in this reasoning. The suicidal risk assessment scale RSD can be cited in particular. It is composed of eleven sections. The 0 level corresponds to the absence of particular ideas of death or suicide. Levels 1 and 2, the presence of ideas of death. Levels 3-4-5, the presence of suicidal ideas. The difference compared to the majority of the other scales consecrated to the same subject, the passif desire of death, occupies a place totally particular in the RSD (level 6). From the level 7, the risk of acting out seems to become more important. It stops being a simple idea of suicide, but becomes a real will of dying, firstly retained by something or someone (level 7), the fear of causing suffering to dear ones or a religious belief., then determined (level 8). Finally, the patient has elaborated a concrete plan (level 9) or he has already started the preparation of acting out (level 10). It is just necessary to evaluate and to note the highest level of the scale. The inclusion of the suicidal risk assessment scale RSD and of the Suicidal Ideation Scale by Beck in an international multicenters, phase IV, double-blind study, according to two parallel groups, with a fixed dose of fluoxétine or fluvoxamine for six weeks, allowed to search correlations which could exist between the two scales. The ana-lysis before the beginning of the treatment was done on 108 outpatients depressive, male and female, aged 18 or over. It finds a satisfactory concurrent validity between the suicidal risk assessment scale RSD and the

  3. Electronic structure engineering of ZnO with the modified Becke-Johnson exchange versus the classical correlation potential approaches

    KAUST Repository

    Ul Haq, Bakhtiar

    2013-12-01

    In this study, we report investigations of structural and electronic properties of ZnO in wurtzite (WZ), rock salt (RS) and zinc-blende (ZB) phases. Calculations have been done with full-potential linearized augmented plane wave plus local orbital method developed within the frame work of Density Functional Theory (DFT). For structural properties investigations, Perdew and Wang proposed local density approximations (LDA) and Perdew et al. proposed generalized gradient approximations (GGA) have been applied. Where for electronic properties in addition to these, Tran-Blaha modified Becke-Johnson (mBJ) potential has been used. Our computed band gap values of ZnO in WZ and ZB phases with mBJ potential are significantly improved compared to those with LDA and GGA; however, in RS phase, energy gap is significantly overestimated compared to experimental measurements. The Zn-d band was found to be more narrower with mBJ potential than that of LDA and GGA. On the other hand, our evaluated crystal field splitting energy values overestimate the experimental values. © 2013 Taylor and Francis.

  4. Factor structure of the Beck Depression Inventory-Second Edition (BDI-II) with Puerto Rican elderly.

    Science.gov (United States)

    Rodríguez-Gómez, José R; Dávila-Martínez, Mariel G; Collazo-Rodríguez, Luis C

    2006-06-01

    The Beck Depression Inventory-Second Edition (BDI-II; (1) is one of the most useful measures for depressive symptomatology in many countries (2). The psychometric properties of this inventory, however, have not been reported with Puerto Rican elderly. This paper reports, exploratory psychometric results with a sample of 410 elderly Puerto Rican (65 years and older; men=94, women=316). The assessment of the construct validity of the BDI-II yielded four factors accounting for 52% of total variance and an internal reliability coefficient (alpha Cronbach) of .89. A factor analysis with the 21 items of the BDI-II was performed using principal component analysis as the extraction method and Varimax rotation. This analysis revealed that the BDI-II was a good measure of the dimensions of depressive symptomatology in the present sample, which resembled prior findings reported with the general Puerto Rican Population (3). This study also reports further data supporting the reliability, validity, and practical utility of the BDI-II for the Puerto Rican population including elders. Implications for potential research with minorities and clinical uses of the BDI-II are also discussed.

  5. The structural, electronic and optical response of IIA-VIA compounds through the modified Becke-Johnson potential

    Science.gov (United States)

    Ali, Roshan; Mohammad, S.; Ullah, Hamid; Khan, S. A.; Uddin, H.; Khan, M.; Khan, N. U.

    2013-02-01

    The structural, electronic and optical properties of IIA-VIA compounds are performed, by using the full-potential linearized augmented plan wave (FP-LAPW) method within DFT, by using the (PBEsol-GGA 2008) version. We have compared the modified Becke-Johnson (mBJ) potential to LDA, GGA and EV-GGA approximations. The IIA-VIA compounds have rock salt structure (B1) and zinc-blend structure (B3). The results obtained for band structure using mBJ show a significant improvement over previous theoretical work and give closer values to the experimental results. The bandgaps less than 3.1 eV are used in the visible light devices applications, while those with bandgaps bigger than 3.1 eV, used in UV devices applications. Optical parameters, like the dielectric constant, refractive indices, reflectivity, optical conductivity and absorption coefficient are calculated and analyzed. Refractive index lesser than unity (vg=c/n) shows that the group velocity of the incident radiation is greater than the speed of light.

  6. Expression profile analysis of mycotoxin-related genes in cartilage with endemic osteochondropathy kashin-beck disease

    Directory of Open Access Journals (Sweden)

    Zhang Feng

    2012-07-01

    Full Text Available Abstract Background Kashin-Beck Disease (KBD is an endemic osteochondropathy. Mycotoxins are believed to play an important role in the pathogenesis of KBD. Because the molecular mechanism of mycotoxin-induced cartilage lesions remains unclear, there is not effective treatment for KBD now. To identify key genes involved in the mycotoxin-induced cartilage lesions, we compared the expression profiles of mycotoxin-related genes (MRG between KBD cartilage and healthy cartilage. Methods Total RNA was isolated from cartilage samples, following by being amplified, labeled and hybridized to Agilent human whole genome microarray chip. qRT-PCR was conducted to validate the microarray data. 1,167 MRG were derived from the environmentally related genomic database Toxicogenomics. The microarray data of MRG was subjected to single gene and gene ontology (GO expression analysis for identifying differently expressed genes and GO. Results We identified 7 up-regulated MRG and 2 down-regulated MRG in KBD cartilage, involved in collagen, apoptosis, metabolism and growth & development. GO expression analysis found that 4 apoptosis-related GO and 5 growth & development-related GO were significantly up-regulated in KBD cartilage. Conclusions Based on the results of previous and our studies, we suggest that mycotoxins might contribute to the development of KBD through dysfunction of MRG involved in collagen, apoptosis and growth & development in cartilage.

  7. Exploring Genome-wide DNA Methylation Profiles Altered in Kashin-Beck Disease Using Infinium Human Methylation 450 Bead Chips.

    Science.gov (United States)

    Shi, Xiao Wei; Shi, Bo Hui; Lyu, Ai Li; Zhang, Feng; Zhou, Tian Tian; Guo, Xiong

    2016-07-01

    To understand how differentially methylated genes (DMGs) might affect the pathogenesis of Kashin-Beck disease (KBD). Genome-wide methylation profiling of whole blood from 12 matched KBD and controls pairs was performed using a high-resolution Infinium 450 K methylation array. In total, 97 CpG sites were differentially methylated in KBD compared to the normal controls; of these sites, 36 sites were significantly hypermethylated (covering 22 genes) and 61 sites were significantly hypomethylated (covering 34 genes). Of these genes, 14 significant pathways were identified, the most significant P value pathway was type I diabetes mellitus pathway and pathways associated with autoimmune diseases and inflammatory diseases were included in this study. Subsequently, 4 CpG sites in HLA-DRB1 were validated using bisulfite sequencing polymerase chain reaction (BSP) in articular cartilage, and the results showed significant differences in the methylation status between KBD and controls, consistent with the results of the high-resolution array. These results suggested that differences in genome-wide DNA methylation exist between KBD and the controls, and the biological pathways support the autoimmune disease and inflammatory disease hypothesis of KBD.

  8. Exploring Genome-wide DNA Methylation Profiles Altered in Kashin-Beck Disease Using Infinium Human Methylation 450 Bead Chips.

    Science.gov (United States)

    Shi, Xiao Wei; Shi, Bo Hui; Lyu, Ai Li; Zhang, Feng; Zhou, Tian Tian; Guo, Xiong

    2016-07-01

    To understand how differentially methylated genes (DMGs) might affect the pathogenesis of Kashin-Beck disease (KBD). Genome-wide methylation profiling of whole blood from 12 matched KBD and controls pairs was performed using a high-resolution Infinium 450 K methylation array. In total, 97 CpG sites were differentially methylated in KBD compared to the normal controls; of these sites, 36 sites were significantly hypermethylated (covering 22 genes) and 61 sites were significantly hypomethylated (covering 34 genes). Of these genes, 14 significant pathways were identified, the most significant P value pathway was type I diabetes mellitus pathway and pathways associated with autoimmune diseases and inflammatory diseases were included in this study. Subsequently, 4 CpG sites in HLA-DRB1 were validated using bisulfite sequencing polymerase chain reaction (BSP) in articular cartilage, and the results showed significant differences in the methylation status between KBD and controls, consistent with the results of the high-resolution array. These results suggested that differences in genome-wide DNA methylation exist between KBD and the controls, and the biological pathways support the autoimmune disease and inflammatory disease hypothesis of KBD. PMID:27554126

  9. Electronic structure engineering of ZnO with the modified Becke-Johnson exchange versus the classical correlation potential approaches

    Science.gov (United States)

    Haq, Bakhtiar Ul; Ahmed, R.; Goumri-Said, Souraya; Shaari, A.; Afaq, A.

    2013-12-01

    In this study, we report investigations of structural and electronic properties of ZnO in wurtzite (WZ), rock salt (RS) and zinc-blende (ZB) phases. Calculations have been done with full-potential linearized augmented plane wave plus local orbital method developed within the frame work of Density Functional Theory (DFT). For structural properties investigations, Perdew and Wang proposed local density approximations (LDA) and Perdew et al. proposed generalized gradient approximations (GGA) have been applied. Where for electronic properties in addition to these, Tran-Blaha modified Becke-Johnson (mBJ) potential has been used. Our computed band gap values of ZnO in WZ and ZB phases with mBJ potential are significantly improved compared to those with LDA and GGA; however, in RS phase, energy gap is significantly overestimated compared to experimental measurements. The Zn-d band was found to be more narrower with mBJ potential than that of LDA and GGA. On the other hand, our evaluated crystal field splitting energy values overestimate the experimental values.

  10. Optical response of mixed molybdenum dichalcogenides for solar cell applications using the modified Becke-Johnson potential

    Energy Technology Data Exchange (ETDEWEB)

    Ahuja, Ushma [Sardar Patel College of Engineering, Mumbai (India). Dept. of Electrical Engineering; Joshi, Ritu; Venugopalan, K. [M.L. Sukhadia Univ., Udaipur (India). Dept. of Physics; Kothari, D.C. [Mumbai Univ. (India). National Center for Nanosciences and Nanotechnology; Tiwari, Harpal [Malaviya National Institute of Technology, Jaipur (India). Dept. of Electrical Engineering

    2016-07-01

    Energy bands and density of states (DOS) of mixed molybdenum dichalcogenides like MoS{sub 2}, MoSeS, MoSe{sub 2}, MoTe{sub 2}, MoTeS, and MoTe{sub 0.5}S{sub 1.5} are reported for the first time using the Tran-Blaha modified Becke-Johnson potential within full potential-linearised augmented plane wave technique. From the partial DOS, a strong hybridisation between the Mo-d and chalcogen-p states is observed below the Fermi energy E{sub F}. In addition, the dielectric constants, absorption coefficients, and refractivity spectra of these compounds have also been deduced. The integrated absorption coefficients derived from the frequency-dependent absorption spectra within the energy range of 0-4.5 eV show a possibility of using molybdenum dichalcogenides, particularly MoTe{sub 0.5}S{sub 1.5}, in solar cell applications. Birefringence and degree of anisotropy are also discussed using the data on refractivity and imaginary components of the dielectric constant.

  11. Proposal for a short version of the Beck Hopelessness Scale based on a national representative survey in Hungary.

    Science.gov (United States)

    Perczel Forintos, Dóra; Rózsa, Sándor; Pilling, János; Kopp, Mária

    2013-12-01

    In our study we assessed the frequency of reported hopelessness and suicide attempts in the national representative survey Hungarostudy 2002. The randomly selected sample consisted of 14,000 individuals over the age of 18. We created a short version of the widely used Beck Hopelessness Scale for screening purposes in suicide prevention. The short version of the BHS consists of four items and has high internal consistency (Cronbach's alpha = 0.85). Moreover, we conducted an investigation into psychological, somatic, sociological and socio-economic as well as cultural variables that show a positive or negative correlation with hopelessness and important predictors of suicide. The following psychological variables showing a positive correlation with hopelessness were identified: dysfunctional attitudes, exhaustion, psychological distress, hostility, lack of life goals and inability to cope emotionally. Sense of coherence, social support, perceived self-efficiency, subjective well-being and problem-solving coping showed a negative correlation with hopelessness. Concerning the relationship between hopelessness and suicide attempts, we found that participants who attempted suicide in the last year scored higher (mean = 4.86) than participants who attempted suicide more than 3 years ago (mean = 3.57). These results indicate that applying the short version of the BHS could be very useful in general practice and in psychiatric care. PMID:23756722

  12. Optical response of mixed molybdenum dichalcogenides for solar cell applications using the modified Becke-Johnson potential

    International Nuclear Information System (INIS)

    Energy bands and density of states (DOS) of mixed molybdenum dichalcogenides like MoS2, MoSeS, MoSe2, MoTe2, MoTeS, and MoTe0.5S1.5 are reported for the first time using the Tran-Blaha modified Becke-Johnson potential within full potential-linearised augmented plane wave technique. From the partial DOS, a strong hybridisation between the Mo-d and chalcogen-p states is observed below the Fermi energy EF. In addition, the dielectric constants, absorption coefficients, and refractivity spectra of these compounds have also been deduced. The integrated absorption coefficients derived from the frequency-dependent absorption spectra within the energy range of 0-4.5 eV show a possibility of using molybdenum dichalcogenides, particularly MoTe0.5S1.5, in solar cell applications. Birefringence and degree of anisotropy are also discussed using the data on refractivity and imaginary components of the dielectric constant.

  13. Relationship between selenium concentration in child hair and the distribution of Kashin-Beck Disease in Tibet,China

    Institute of Scientific and Technical Information of China (English)

    LI Shunjiang; YANG Linsheng; WANG Wuyi; LI Yonghua; LI Hairong; XIRAO Ruodeng

    2007-01-01

    The focus of this study is to determine the relationship between selenium(Se)concentrations in child hair and the distribution of Kashin-Beck disease(KBD)in Tibet.The hair of children in typical KBD-affected areas and non-disease areas was collected,and its Se concentrations were measured by atomic fluorescent spectrometry.The Se concentrations in child hair were (0.13±0.04)and (0.1 8±0.07)μg/g respectively in KBD areas and non-disease areas respectively,which are significantly difierent.In areas supplemented with Se in Tibet,the Se concentration of hair in KBD-affected areas was higher than that in non-diseased areas,being(0.28±0.03)and(0.18±0.04)μg/g respectively.There is a close relationship between the Se concentrations in hair and KBD distribution.Se supplement increase the Se concentrations in the human body.Appropriate Se supplementation is important to prevent KBD in Tibet.

  14. Optical Response of Mixed Molybdenum Dichalcogenides for Solar Cell Applications Using the Modified Becke-Johnson Potential

    Science.gov (United States)

    Ahuja, Ushma; Joshi, Ritu; Kothari, D. C.; Tiwari, Harpal; Venugopalan, K.

    2016-03-01

    Energy bands and density of states (DOS) of mixed molybdenum dichalcogenides like MoS2, MoSeS, MoSe2, MoTe2, MoTeS, and MoTe0.5S1.5 are reported for the first time using the Tran-Blaha modified Becke-Johnson potential within full potential-linearised augmented plane wave technique. From the partial DOS, a strong hybridisation between the Mo-d and chalcogen-p states is observed below the Fermi energy EF. In addition, the dielectric constants, absorption coefficients, and refractivity spectra of these compounds have also been deduced. The integrated absorption coefficients derived from the frequency-dependent absorption spectra within the energy range of 0-4.5 eV show a possibility of using molybdenum dichalcogenides, particularly MoTe0.5S1.5, in solar cell applications. Birefringence and degree of anisotropy are also discussed using the data on refractivity and imaginary components of the dielectric constant.

  15. Biological reduction of iron to the elemental state from ochre deposits of Skelton Beck in Northeast England

    Directory of Open Access Journals (Sweden)

    Pattanathu K S M Rahman

    2014-06-01

    Full Text Available Ochre, consequence of acid mine drainage, is iron oxides-rich soil pigments that can be found in the water drainage from historic base metal and coal mines. The anaerobic strains of Geobacter sulfurreducens and Shewanella denitrificans were used for the microbial reduction of iron from samples of ochre collected from Skelton Beck (Saltburn Orange River, NZ 66738 21588 in Northeast England. The aim of the research was to determine the ability of the two anaerobic bacteria to reduce the iron present in ochre and to determine the rate of the reduction process. The physico-chemical changes in the ochre sample after the microbial reduction process were observed by the production of zero-valent iron which was later confirmed by the detection of elemental Fe in XRD spectrum. The XRF results revealed that 69.16% and 84.82% of iron oxide can be reduced using G. sulfurreducens and S. denitrificans respectively after 8 days of incubation. These results could provide the basis for the development of a biohydrometallurgical process for the production of elemental iron from ochre sediments.

  16. Sintomas depressivos no câncer de mama: Inventário de Depressão de Beck - Short Form Depressive symptoms in breast cancer: Beck Depression Inventory - Short Form

    Directory of Open Access Journals (Sweden)

    Renata de Oliveira Cangussu

    2010-01-01

    Full Text Available OBJETIVOS: Verificar a prevalência de sintomas depressivos em mulheres com câncer de mama e identificar os fatores de risco associados à sua ocorrência. MÉTODOS: Foi realizado um estudo transversal, em que foram entrevistadas 71 mulheres com câncer de mama. Foram empregados dois instrumentos: um questionário para verificar os dados sociodemográficos e clínicos e o Inventário de Depressão de Beck - Short Form (BDI-SF, para avaliação dos sintomas depressivos. Para análise dos dados, utilizaram-se medidas descritivas e o teste de qui-quadrado, que avaliou a associação entre variáveis sociodemográficas e clínicas e os sintomas depressivos. O nível de significância considerado foi de 5%. RESULTADOS: A prevalência de sintomas depressivos foi de 29,6%. Os fatores associados à presença desses sintomas foram o tratamento quimioterápico (p = 0,021, presença de dor (p = 0,018 e limitação do movimento do membro superior (p = 0,010 e pior percepção da saúde (p = 0,018. CONCLUSÃO: Sintomas depressivos são frequentes no câncer de mama, assim a saúde mental das mulheres com esse tipo de câncer deve ser investigada e tratada quando necessário, reduzindo o impacto desses sintomas na vida da mulher.OBJECTIVES: To verify the prevalence of depressive symptoms in women with breast cancer and identify risk factors associated to its occurrence. METHODS: It was a transversal study where 71 women with breast cancer were interviewed. Two instruments were applied, being one questionnaire used to verify sociodemographic and clinical data, and the Beck Depression Inventory - Short Form to evaluate depressive symptoms. Descriptive methods and chi-square test were utilized to analyze data, evaluating association between depressive symptoms, sociodemographic and clinical data. Significance level was considered of 5%. RESULTS: Depressive symptoms prevalence was 29,6%. Factors associated to the presence of this kind of symptoms were

  17. Validação da bateria "Beck" de testes de habilidades para atletas brasileiros de "rugby" em cadeira de rodas Validation of beck battery of skills tests to Brazilian players of wheelchair rugby

    Directory of Open Access Journals (Sweden)

    José Irineu Gorla

    2011-09-01

    Full Text Available O "Rugby" em Cadeira de Rodas é uma modalidade praticada por sujeitos com tetraplegia ou tetra-equivalência, desde 2005 no Brasil, onde existem aproximadamente 10 equipes em atividade. A avaliação motora é um dos meios de controle do treinamento que possibilita conquistar avanços no planejamento. A bateria "Beck" de testes de habilidades (manejo de bola, precisão de passes, bloqueio, velocidade e passes de longa distância para atletas da modalidade foi desenvolvida nos EUA por Yilla e Sherrill (1998. O objetivo deste estudo foi analisar os critérios de autenticidade científica da bateria para a população de atletas brasileiros. Os resultados de duas avaliações com a bateria (teste e re-teste realizadas com 11 atletas (média de idade 27,59 ± 5,37 anos, tempo de lesão 8,19 ± 3,83 anos, foram registrados por três avaliadores, o que possibilitou a análise de objetividade, fidedignidade e consistência interna. Foram utilizadas as ferramentas ANOVA para análise de objetividade e, coeficiente de correlação intraclasse e teste t para análise de fidedignidade e consistência. Não foram encontradas diferenças entre os resultados dos diferentes avaliadores (valores de p variando de 0,45 a 1,00 e os valores de correlação intraclasse encontrados (variação de r de 0,78 a 0,99 permitem concluir que a bateria é consistente e fidedigna. Os resultados encontrados neste estudo são evidências de que os critérios de autenticidade científica para a bateria são satisfeitos e a bateria pode ser considerada um instrumento válido para avaliação motora de atletas brasileiros de "rugby" em cadeira de rodas.The Wheelchair Rugby is a sport practiced by subjects with tetraplegia or tetra-equivalence, since 2005 in Brazil, where there are approximately 10 teams in business. The motricity evaluation is a means of training control that allows achieve real progress in planning. The BECK battery of skills tests (ball handling, precision

  18. Comparison of mineral intake between children from endemic and non-endemic areas for Kashin-Beck disease in Tibet Autonomous Region: Pilote study

    OpenAIRE

    Dermience, Michael; Maesen, Philippe; Mathieu, Françoise; De Maertelaer, Viviane; Lognay, Georges

    2012-01-01

    Background The Kashin-Beck disease (KBD) is an endemic and chronic osteochondropathy affecting between 0.74 million and 2.5 million people in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. The etiology remains unclear, although a multifactorial hypothesis has been proposed (selenium/iodine deficiency; high concentration of organic matters in drinking water; and mycotoxin poisoning by fungi infecting cereals). The rural population is almost exclusive...

  19. Is the beck anxiety inventory a good tool to assess the severity of anxiety? A primary care study in the Netherlands Study of Depression and Anxiety (NESDA)

    OpenAIRE

    van der Feltz-Cornelis Christina M; Muntingh Anna DT; van Marwijk Harm WJ; Spinhoven Philip; Penninx Brenda WJH; van Balkom Anton JLM

    2011-01-01

    Abstract Background Appropriate management of anxiety disorders in primary care requires clinical assessment and monitoring of the severity of the anxiety. This study focuses on the Beck Anxiety Inventory (BAI) as a severity indicator for anxiety in primary care patients with different anxiety disorders (social phobia, panic disorder with or without agoraphobia, agoraphobia or generalized anxiety disorder), depressive disorders or no disorder (controls). Methods Participants were 1601 primary...

  20. Depressive Symptoms in People with and without Alcohol Abuse: Factor Structure and Measurement Invariance of the Beck Depression Inventory (BDI-II) Across Groups

    OpenAIRE

    Cecilie Skule; Pål Ulleberg; Hilde Dallavara Lending; Torkil Berge; Jens Egeland; Tim Brennen; Nils Inge Landrø

    2014-01-01

    This study explored differences in the factor structure of depressive symptoms in patients with and without alcohol abuse, and differences in the severity of depressive symptoms between the two groups. In a sample of 358 patients without alcohol problems and 167 patients with comorbid alcohol problems, confirmatory factor analysis revealed that the same factor structures, Beck et al.'s two-factor Somatic Affective-Cognitive (SA-C) model, and Buckley et al.'s three-factor Cognitive-Affective- ...

  1. Optoelectronic and thermoelectric properties of Zintl YLi3 A 2 (A = Sb, Bi) compounds through modified Becke-Johnson potential

    Science.gov (United States)

    Seddik, T.; Uğur, G.; Khenata, R.; Uğur, Ş.; Soyalp, F.; Murtaza, G.; Rai, D. P.; Bouhemadou, A.; Omran, S. Bin

    2016-10-01

    In the present work, we investigate the structural, optoelectronic and thermoelectric properties of the YLi3 X 2 (X = Sb, Bi) compounds using the full potential augmented plane wave plus local orbital (FP-APW+lo) method. The exchange-correlation potential is treated with the generalized gradient approximation/local density approximation (GGA/LDA) and with the modified Becke-Johnson potential (TB-mBJ) in order to improve the electronic band structure calculations. In addition, the estimated ground state properties such as the lattice constants, external parameters, and bulk moduli agree well with the available experimental data. Our band structure calculations with GGA and LDA predict that both compounds have semimetallic behaviors. However, the band structure calculations with the GGA/TB-mBJ approximation indicate that the ground state of the YLi3Sb2 compound is semiconducting and has an estimated indirect band gap (Γ-L) of about 0.036 eV while the ground state of YLi3Bi2 compound is semimetallic. Conversely the LDA/TB-mBJ calculations indicate that both compounds exhibit semiconducting characters and have an indirect band gap (Γ-L) of about 0.15 eV and 0.081 eV for YLi3Sb and YLi3Bi2 respectively. Additionally, the optical properties reveal strong responses of the herein materials in the energy range between the IR and extreme UV regions. Thermoelectric properties such as thermal conductivity, electrical conductivity, Seebeck coefficient, and thermo power factors are also calculated.

  2. Is It the Appropriate Time to Stop Applying Selenium Enriched Salt in Kashin-Beck Disease Areas in China?

    Directory of Open Access Journals (Sweden)

    Yujie Ning

    2015-07-01

    Full Text Available We aimed to identify significant factors of selenium (Se nutrition of children in Kashin-Beck disease (KBD endemic areas and non-KBD area in Shaanxi Province for providing evidence of whether it is the time to stop applying Se-enriched salt in KBD areas. A cross-sectional study contained 368 stratified randomly selected children aged 4–14 years was conducted with 24-h retrospective questionnaire based on a pre-investigation. Food and hair samples were collected and had Se contents determined with hydride generation atomic fluorescence spectrometry. Average hair Se content of 349.0 ± 60.2 ng/g in KBD-endemic counties was significantly lower than 374.1 ± 47.0 ng/g in non-KBD counties. It was significantly higher in the male children (365.2 ± 52.3 ng/g than in the female (345.0 ± 62.2 ng/g, p = 0.002 and significantly higher in the 4.0–6.9 years group (375.2 ± 58.9 ng/g than the 7.0–14.0 years group (347.0 ± 56.1 ng/g, p < 0.01. Gender, living area, Se intake without supplements, Se-enriched salt, oil source and protein intake were identified as significant factors of hair Se contents. Cereals, meat and milk were commonly included as significant food categories that mainly contributed to Se intake without supplement of the whole population. Balanced dietary structure without Se supplement could effectively enhance and maintain children’s Se nutrition. It may be the time to stop applying Se-enriched salt in KBD areas in Shaanxi Province.

  3. Assessing cognitive insight in nonpsychiatric individuals and outpatients with schizophrenia in Taiwan: an investigation using the Beck Cognitive Insight Scale

    Directory of Open Access Journals (Sweden)

    Lu Chien-Wen

    2011-10-01

    Full Text Available Abstract Background The Beck Cognitive Insight Scale (BCIS was designed for the assessment of the cognitive processes involved in self-reflection and the ability to modify erroneous beliefs and misinterpretations. Studies investigating the factor structure of the BCIS have indicated a two-factor model in the psychotic population. The factor structure of the BCIS, however, has not received much consideration in the nonpsychiatric population. The present study examined the factor structure and validity of the BCIS and compared its scores between nonpsychiatric individuals and outpatients with psychosis. Method The Taiwanese version of the BCIS was administered to 507 nonpsychiatric individuals and 118 outpatients with schizophrenia. The psychometric properties of the BCIS were examined through the following analyses: exploratory and confirmatory factor analyses, reliability, correlation analyses, and discriminative validity. Results The BCIS showed adequate internal consistency and stability over time. Exploratory and confirmatory factor analyses on the 15-item measure indicated a two-factor solution that supported the two dimensions of the Taiwanese BCIS, which was also observed with the original BCIS. Following the construct validation, we obtained a composite index (self-reflectiveness minus self-certainty of the Taiwanese BCIS that reflected cognitive insight. Consistent with previous studies, our results indicated that psychosis is associated with low self-reflectiveness and high self-certainty, which possibly reflect lower cognitive insight. Our results also showed that better cognitive insight is related to worse depression in patients with schizophrenia spectrum disorders, but not in nonpsychiatric individuals. The receiver operating characteristic (ROC analyses revealed that the area under the curve (AUC was 0.731. A composite index of 3 was a good limit, with a sensitivity of 87% and a specificity of 51%. Conclusion The BCIS proved to be

  4. Dimensional and hierarchical models of depression using the Beck Depression Inventory-II in an Arab college student sample

    Directory of Open Access Journals (Sweden)

    Ohaeri Jude U

    2010-07-01

    Full Text Available Abstract Background An understanding of depressive symptomatology from the perspective of confirmatory factor analysis (CFA could facilitate valid and interpretable comparisons across cultures. The objectives of the study were: (i using the responses of a sample of Arab college students to the Beck Depression Inventory (BDI-II in CFA, to compare the "goodness of fit" indices of the original dimensional three-and two-factor first-order models, and their modifications, with the corresponding hierarchical models (i.e., higher - order and bifactor models; (ii to assess the psychometric characteristics of the BDI-II, including convergent/discriminant validity with the Hopkins Symptom Checklist (HSCL-25. Method Participants (N = 624 were Kuwaiti national college students, who completed the questionnaires in class. CFA was done by AMOS, version 16. Eleven models were compared using eight "fit" indices. Results In CFA, all the models met most "fit" criteria. While the higher-order model did not provide improved fit over the dimensional first - order factor models, the bifactor model (BFM had the best fit indices (CMNI/DF = 1.73; GFI = 0.96; RMSEA = 0.034. All regression weights of the dimensional models were significantly different from zero (P Conclusion The broadly adequate fit of the various models indicates that they have some merit and implies that the relationship between the domains of depression probably contains hierarchical and dimensional elements. The bifactor model is emerging as the best way to account for the clinical heterogeneity of depression. The psychometric characteristics of the BDI-II lend support to our CFA results.

  5. Factor Structure and Clinical Utility of the Beck Depression Inventory in Patients with Binge Eating Disorder and Obesity

    Science.gov (United States)

    Udo, Tomoko; McKee, Sherry A.; Grilo, Carlos M.

    2015-01-01

    Objective The Beck Depression Inventory (BDI) is often used to assess depression symptoms, but its factor structure and clinical utility have not been evaluated in patients with binge eating disorder (BED) and obesity. Methods 882 treatment-seeking obese patients with BED were administered structured interviews (SCID-I/P) and completed self-report questionnaires. Results Exploratory and confirmatory factor analyses supported a brief 16-item BDI version with a three-factor structure (affective, attitudinal, and somatic). Both 21- and 16-item versions showed excellent internal consistency (both α=0.89) and had significant correlation patterns with different aspects of eating disorder psychopathology; three factors showed significant but variable associations with eating disorder psychopathology. Area under the curves (AUC) for both BDI versions were significant in predicting major depressive disorder (MDD; AUC=0.773 [16-item], 73.5% sensitivity/70.2% specificity, AUC=0.769 [21-item], 79.5% sensitivity/64.1% specificity) and mood disorders (AUC=0.763 [16-item], 67.1% sensitivity/71.5% specificity, AUC=0.769 [21-item], 84.2% sensitivity/55.7% specificity). 21-item BDI (cut-off score ≥16) showed higher negative predictive values (94.0% vs. 93.0% [MDD]; 92.4% vs. 88.3% [mood disorders]) than brief 16-item BDI (cut-off score ≥13). Conclusions Both BDI versions demonstrated moderate performance as a screening instrument for MDD/mood disorders in obese patients with BED. Advantages and disadvantages for both versions are discussed. A three-factor structure has potential to inform the conceptualization of depression features. PMID:25537344

  6. [Manfred Schneider. Lübeck im 12. und 13. Jahrhundert. Archäologische Befunde zur entstehung einer mittelalterlichen Grossstadt. In : Expansion - integration? Danish-Baltic Contacts 1147-1410] / Dennis Hortmuth

    Index Scriptorium Estoniae

    Hortmuth, Dennis

    2011-01-01

    Arvustus:Manfred Schneider. Lübeck im 12. und 13. Jahrhundert. Archäologische Befunde zur entstehung einer mittelalterlichen Grossstadt. In : Expansion - integration? Danish-Baltic Contacts 1147-1410 AD. (Vordingborg, 2009).

  7. X-ray image characteristics and related measurements in the ankles of 118 adult patients with Kashin-Beck disease

    Institute of Scientific and Technical Information of China (English)

    Zeng Yi; Zhou Zongke; Shen Bin; Yang Jing; Kang Pengde; Zhou Xuan; Zou Ling

    2014-01-01

    Background Kashin-Beck disease (KBD) is a chronic,degenerative osteoarthropathy that causes severe skeletal deformation.Although many researchers have proven that almost all KBD patients who showed an increaseing proximo-distal gradient had radiographic abnormalities of the ankle,few detailed description of radiographic changes in the ankles of patients with KBD has been reported,especially for variable measurements of ankle changes.The purpose of this study was to demonstrate the radiographic characteristics of the ankles of adult KBD patients.Methods One hundred and eighteen adult KBD patients from september to October 2010 in Rongtang county in China were examined with lateral radiographs of the right ankle.The morphological abnormalities in the talus,calcaneus,navicular bone,distal tibia,and joint space were analyzed,and the calcaneus length,height,length-height ratio,tuber angle,front angle,plantar angle,and distal tibia anteroposterior (AP) length were measured using Riepert's method.Results Eighty-one patients (68.6%) had abnormal ankle radiographs; 72 (88.9%) patients had talus changes,69 (85.2%) patients had calcaneus changes,28 (34.6%) patients had navicular bone changes,and 48 (59.2%) patients had distal tibia changes.For 118 KBD patients,the average calcaneus length was 7.4 cm,height was 4.3 cm,and the length-height ratio was 1.7.The calcaneus tuber angle was 28.2°,front angle was 38.0° and the plantar angle was 74.2°.The distal tibia anteroposterior length was 4.05 cm.Compared with 50 normal adults (control group),significant differences were found for the calcaneus length,the calcaneus length-height ratio,and the distal tibia AP length.Conclusions Patients with KBD have characteristic abnormalities on ankle radiographs; talus depression and deformity,calcaneus shortening deformity,and distal tibia deformity with AP length widening were the most typical changes.

  8. Biogeochemical Cycling

    Science.gov (United States)

    Bebout, Brad; Fonda, Mark (Technical Monitor)

    2002-01-01

    This lecture will introduce the concept of biogeochemical cycling. The roles of microbes in the cycling of nutrients, production and consumption of trace gases, and mineralization will be briefly introduced.

  9. Críticas al paradigma pos-político: en torno al consensualismo de Ulrich Beck y Anthony Giddens

    Directory of Open Access Journals (Sweden)

    Agustín Lewit

    2011-01-01

    Full Text Available This paper attempts to develop a critical reading of two authors registered within of the Theory of Reflexive Modernity, Anthony Giddens and Ulrich Beck, with particular emphasis on the political nature from both authors promote their theoretical propositions. The main objective of this paper is to highlight that the authors mentioned in their quest to eradicate the conflictual element of the political dimension, end up emptying it of its content more appropriate.The main theoretical lifeline that we use to guide our review consists of the theoretical contributions of the Belgian philosopher Chantal Mouffe.

  10. FES cycling.

    Science.gov (United States)

    Newham, D J; Donaldson, N de N

    2007-01-01

    Spinal cord injury (SCI) leads to a partial or complete disruption of motor, sensory, and autonomic nerve pathways below the level of the lesion. In paraplegic patients, functional electrical stimulation (FES) was originally widely considered as a means to restore walking function but this was proved technically very difficult because of the numerous degrees of freedom involved in walking. FES cycling was developed for people with SCI and has the advantages that cycling can be maintained for reasonably long periods in trained muscles and the risk of falls is low. In the article, we review research findings relevant to the successful application of FES cycling including the effects on muscle size, strength and function, and the cardiovascular and bone changes. We also describe important practical considerations in FES cycling regarding the application of surface electrodes, training and setting up the stimulator limitations, implanted stimulators and FES cycling including FES cycling in groups and other FES exercises such as FES rowing.

  11. Cycling more for safer cycling

    OpenAIRE

    VAN HOUT, Kurt

    2009-01-01

    Cycling presents a lot of benefits to the individual and to society. Health, environment, accessibility, local businesses, … all gain when more people cycle. Yet many governments are reluctant when it comes to promoting cycling, mainly because of (perceived) safety issues. Since studies have established a clear and consistent relationship between bicycle use and cyclist accident risk, this lack of bicycle promotion will influence the safety outcome of bicyclists. In this paper the relation be...

  12. Electronic properties of III-nitride semiconductors: A first-principles investigation using the Tran-Blaha modified Becke-Johnson potential

    International Nuclear Information System (INIS)

    In this work, we use density functional theory to investigate the influence of semilocal exchange and correlation effects on the electronic properties of III-nitride semiconductors considering zinc-blende and wurtzite crystal structures. We find that the inclusion of such effects through the use of the Tran-Blaha modified Becke-Johnson potential yields an excellent description of the electronic structures of these materials giving energy band gaps which are systematically larger than the ones obtained with standard functionals such as the generalized gradient approximation. The discrepancy between the experimental and theoretical band gaps is then significantly reduced with semilocal exchange and correlation effects. However, the effective masses are overestimated in the zinc-blende nitrides, but no systematic trend is found in the wurtzite compounds. New results for energy band gaps and effective masses of zinc-blende and wurtzite indium nitrides are presented

  13. Fuel cycles

    International Nuclear Information System (INIS)

    AECL publications, from the open literature, on fuels and fuel cycles used in CANDU reactors are listed in this bibliography. The accompanying index is by subject. The bibliography will be brought up to date periodically

  14. Fes cycling

    Directory of Open Access Journals (Sweden)

    Berkelmans Rik

    2008-01-01

    Full Text Available Many research with functional electrical stimulation (FES has been done to regain mobility and for health benefits. Better results have been reported for FES-cycling than for FES-walking. The majority of the subjects during such research are people with a spinal cord injury (SCI, cause they often lost skin sensation. Besides using surface stimulation also implanted stimulators can be used. This solves the skin sensation problem, but needs a surgery. Many physiological effects of FES-cycling has been reported, e.g., increase of muscles, better blood flow, reduction of pressure ulcers, improved self-image and some reduction of bone mineral density (BMD loss. Also people with an incomplete SCI benefit by FES-cycling, e.g. cycling time without FES, muscle strength and also the walking abilities increased. Hybrid exercise gives an even better cardiovascular training. Presently 4 companies are involved in FES-cycling. They all have a stationary mobility trainer. Two of them also use an outdoor tricycle. One combined with voluntary arm cranking. By optimizing the stimulation parameters the power output and fatigue resistance will increase, but will still be less compared to voluntary cycling.

  15. Koszul cycles

    CERN Document Server

    Bruns, Winfreid; Römer, Tim

    2010-01-01

    We prove regularity bounds for Koszul cycles holding for every ideal of dimension at most 1 in a polynomial ring. We generalize the lower bound for the Green-Lazarsfeld index of Veronese rings we proved in arXiv:0902.2431 to the multihomogeneous setting.

  16. Happy Cycling

    DEFF Research Database (Denmark)

    Geert Jensen, Birgitte; Nielsen, Tom

    2013-01-01

    og Interaktions Design, Aarhus Universitet under opgave teamet: ”Happy Cycling City – Aarhus”. Udfordringen i studieopgaven var at vise nye attraktive løsningsmuligheder i forhold til cyklens og cyklismens integration i byrum samt at påpege relationen mellem design og overordnede diskussioner af...

  17. Glacial cycles

    DEFF Research Database (Denmark)

    Kaufmann, R. K.; Juselius, Katarina

    and compare the accuracy of their in-sample simulations. Results indicate that strong statistical associations between endogenous climate variables are not enough for statistical models to reproduce glacial cycles. Rather, changes in solar insolation associated with changes in Earth's orbit are needed...

  18. 'Extra-regional' strike-slip fault systems in Chile and Alaska: the North Pacific Rim orogenic Stream vs. Beck's Buttress

    Science.gov (United States)

    Redfield, T. F.; Scholl, D. W.; Fitzgerald, P. G.

    2010-12-01

    us to speculate towards the role of obliquity of plate tectonic convergence for the along-strike evolution of extra-regional strike-slip systems. Highly-oblique initiation of the DFS encourages detachment of fault-bounded terranes and provides a driver that encourages a westward-fanning pattern of extrusion towards the free face of the Beringian margin. Plausibly, its less-oblique central segment promotes vertical pathway exhumation observed at (for example) Denali itself. A more orthogonal regime drives the entire LOFZ, precluding slivering at its initiation and promoting upstream buttressing (Beck et al., 1993). The convergent plate boundary setting opens a window through time and space on the evolution of large-magnitude fault-systems. Escape, or not to escape ~ what best answers the question ? Citations Redfield, T. F., Scholl, D. W., Fitzgerald, P. G., and Beck, M. E., & 2007. Escape tectonics and the extrusion of Alaska: past, present, and future. Geology. 35, 11, 1039-1042 Beck, M.E., Rojas, C. and Cembrano, J. (1993). “On the nature of buttressing in margin-parallel strike-fault systems.” Geology, Vol. 21, pp. 755-758.

  19. Sulfur cycle

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.

    Ecological Society Symposium held jointly with the Linnean Society of London. Oxford: Blackwell. Huston MH and Smith T (1987) Plant succession: Life history and competition. American Naturalist 130: 168–198. Sulfur Cycle P A Loka Bharathi, National Institute.... Vegetatio 110: 115–147. Odum EP (1969) The strategy of ecosystem development. Science 164: 262–270. Walker KR and Alberstadt LP(1975) Ecological succession asan aspect of structure in fossil communities. Paleobiology 1: 238–257. Author's personal copy S 4 O...

  20. Application of Beck self-rating depression scale among patients with infertility%Beck抑郁自评问卷在不孕症患者中的应用

    Institute of Scientific and Technical Information of China (English)

    谭丽; 张婷婷; 王姿雅; 徐博文

    2011-01-01

    Objective: To research the reliability and validity of Beck self- rating depression scale among patients with infertility,provide a basis for choosing depression self - assessment tool for patients with infertility.Methods: Beck self - rating depression scale was used to investigate 176 patients with infertihty, factor analysis was used to research the reliability and validity of Beck self - rating depression scale.Results: Beck self- rating depression scale chose four factors including pessimism, depression, diminished capacity and low self- evaluation; the Cronbach α coefficients of four dimensions were 0.583, 0.554, 0.398 and 0.529, respectively; the total Cronbach α coefficient was 0.718; the correlation coefficient between dimensions and total score of the questionnaire was 0.43 ~ 0.809 ( P < 0.01 ).Conclusion: The reliability and validity of Beck self - rating depression scale are good, Beck self - rating depression scale can reflect the depression status of infertile cases effectively; the depression status of infertile cases is high, necessary preventive measures should be adopted to intervene the adverse psychological state early.%目的:研究Beck抑郁自评问卷在不孕症患者中使用的信度和效度,为不孕症患者抑郁状态自评工具的选择提供依据.方法:应用Beck抑郁白评问卷(BDI),对176例不孕症患者进行调查,采用因素分析方法研究BDI的信度和效度.结果:BDI提取了悲观情绪、抑郁情绪、能力减退、自我评价低4个因子;该问卷Cronbach α系数4个构面分别是0.583,0.554、0.398、0.529,总Cronbach α系数为0.718;各分维度与问卷总分的相关在0.43~0.809之间(P<0.01).结论:Beck抑郁自评问卷具有较好的信度和效度,可以有效反映不孕症患者的抑郁状态.不孕症患者抑郁状态较高,应采取必要的预防措施对其不良心理状态进行早期干预.

  1. Prevalence of depression and its associated factors using Beck Depression Inventory among students of School of Health and Nutrition, Tabriz, Iran in 2009

    Directory of Open Access Journals (Sweden)

    Saeid Safiri

    2013-12-01

    Full Text Available BACKGROUND: Depression is a debilitating disease which is caused by social and environmental factors in additionto genetic factors. University students are among the young and vulnerable population to depression and theirpopulation is increasing with increase in universities and higher education institutions. Therefore, any disturbance instudent's mental and physical health is a serious threat for the next generation. In this study, we aimed to estimate theprevalence of depression and its related factors in students of School of Health and Nutrition at Tabriz University ofMedical Sciences, Iran. METHODS: This was a cross-sectional survey on 175 students selected by stratified random sampling, educating indifferent fields at School of Health and Nutrition in 2009. The data collection tool was the short form of the standardBeck Depression Inventory (BDI which is used for screening depression. The collected data were analyzed by softwareStata Statistical Software, Release 10.0 (Stata Corporation, College Station, TX, USA. RESULTS: The results showed that 62.7% of the students had depression and from these 10.9% suffered from severedepression. Significantly higher depression rates were seen in students with worrisome about the future. Marriedstudents, those interested in their field of study, those performing prayers and regularly reading the Quran hadsignificantly lower rates of depression. CONCLUSIONS: Due to the high prevalence of depression, screening strategies should be implemented to identifydepressed students. Counseling services should be available and accessible to students at risk.

  2. Substance Use and Depression Symptomatology: Measurement Invariance of the Beck Depression Inventory (BDI-II among Non-Users and Frequent-Users of Alcohol, Nicotine and Cannabis.

    Directory of Open Access Journals (Sweden)

    Ashlee A Moore

    Full Text Available Depression is a highly heterogeneous condition, and identifying how symptoms present in various groups may greatly increase our understanding of its etiology. Importantly, Major Depressive Disorder is strongly linked with Substance Use Disorders, which may ameliorate or exacerbate specific depression symptoms. It is therefore quite plausible that depression may present with different symptom profiles depending on an individual's substance use status. Given these observations, it is important to examine the underlying construct of depression in groups of substance users compared to non-users. In this study we use a non-clinical sample to examine the measurement structure of the Beck Depression Inventory (BDI-II in non-users and frequent-users of various substances. Specifically, measurement invariance was examined across those who do vs. do not use alcohol, nicotine, and cannabis. Results indicate strict factorial invariance across non-users and frequent-users of alcohol and cannabis, and metric invariance across non-users and frequent-users of nicotine. This implies that the factor structure of the BDI-II is similar across all substance use groups.

  3. Substance Use and Depression Symptomatology: Measurement Invariance of the Beck Depression Inventory (BDI-II) among Non-Users and Frequent-Users of Alcohol, Nicotine and Cannabis.

    Science.gov (United States)

    Moore, Ashlee A; Neale, Michael C; Silberg, Judy L; Verhulst, Brad

    2016-01-01

    Depression is a highly heterogeneous condition, and identifying how symptoms present in various groups may greatly increase our understanding of its etiology. Importantly, Major Depressive Disorder is strongly linked with Substance Use Disorders, which may ameliorate or exacerbate specific depression symptoms. It is therefore quite plausible that depression may present with different symptom profiles depending on an individual's substance use status. Given these observations, it is important to examine the underlying construct of depression in groups of substance users compared to non-users. In this study we use a non-clinical sample to examine the measurement structure of the Beck Depression Inventory (BDI-II) in non-users and frequent-users of various substances. Specifically, measurement invariance was examined across those who do vs. do not use alcohol, nicotine, and cannabis. Results indicate strict factorial invariance across non-users and frequent-users of alcohol and cannabis, and metric invariance across non-users and frequent-users of nicotine. This implies that the factor structure of the BDI-II is similar across all substance use groups. PMID:27046165

  4. Insights in the electronic structure and redox reaction energy in LiFePO{sub 4} battery material from an accurate Tran-Blaha modified Becke Johnson potential

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Rafael B., E-mail: rafael.barros@physics.uu.se [Condensed Matter Theory Group, Department of Physics and Astronomy, Box 516, Uppsala University, S-75120 Uppsala (Sweden); Almeida, J. de S [Condensed Matter Theory Group, Department of Physics and Astronomy, Box 516, Uppsala University, S-75120 Uppsala (Sweden); Instituto de Física, Universidade Federal da Bahia, Salvador, Bahia (Brazil); Ferreira da Silva, A. [Instituto de Física, Universidade Federal da Bahia, Salvador, Bahia (Brazil); Ahuja, Rajeev [Condensed Matter Theory Group, Department of Physics and Astronomy, Box 516, Uppsala University, S-75120 Uppsala (Sweden); Applied Materials Physics, Department of Materials and Engineering, Royal Institute of Technology (KTH), S-100 44 Stockholm (Sweden)

    2015-09-28

    The main goals of this paper are to investigate the accuracy of the Tran-Blaha modified Becke Johnson (TB-mBJ) potential to predict the electronic structure of lithium iron phosphate and the related redox reaction energy with the lithium deintercalation process. The computed electronic structures show that the TB-mBJ method is able to partially localize Fe-3d electrons in LiFePO{sub 4} and FePO{sub 4} which usually is a problem for the generalized gradient approximation (GGA) due to the self interaction error. The energy band gap is also improved by the TB-mBJ calculations in comparison with the GGA results. It turned out, however, that the redox reaction energy evaluated by the TB-mBJ technique is not in good agreement with the measured one. It is speculated that this disagreement in the computed redox energy and the experimental value is due to the lack of a formal expression to evaluate the exchange and correlation energy. Therefore, the TB-mBJ is an efficient method to improve the prediction of the electronic structures coming form the standard GGA functional in LiFePO{sub 4} and FePO{sub 4}. However, it does not appear to have the same efficiency for evaluating the redox reaction energies for the investigated system.

  5. Depressive symptoms in people with and without alcohol abuse: factor structure and measurement invariance of the Beck Depression Inventory (BDI-II) across groups.

    Science.gov (United States)

    Skule, Cecilie; Ulleberg, Pål; Dallavara Lending, Hilde; Berge, Torkil; Egeland, Jens; Brennen, Tim; Landrø, Nils Inge

    2014-01-01

    This study explored differences in the factor structure of depressive symptoms in patients with and without alcohol abuse, and differences in the severity of depressive symptoms between the two groups. In a sample of 358 patients without alcohol problems and 167 patients with comorbid alcohol problems, confirmatory factor analysis revealed that the same factor structures, Beck et al.'s two-factor Somatic Affective-Cognitive (SA-C) model, and Buckley et al.'s three-factor Cognitive-Affective- Somatic (C-A-S) model, demonstrated the best fit to the data in both groups. The SA-C model was preferred due to its more parsimonious nature. Evidence for strict measurement invariance across the two groups for the SA-C model was found. MIMIC (multiple-indicator-multiple-cause) modeling showed that the level of depressive symptoms was found to be highest on both factors in the group with comorbid alcohol problems. The magnitude of the differences in latent mean scores suggested a moderate difference in the level of depressive symptoms between the two groups. It is argued that patients with comorbid depression and alcohol abuse should be offered parallel and adequate treatment for both conditions. PMID:24533075

  6. Improved half-metallic gap of zincblende half-metal superlattices with the Tran-Blaha modified Becke-Johnson density functional

    Science.gov (United States)

    Guo, San-Dong

    2016-08-01

    Binary transition-metal pnictides and chalcogenides half-metallic ferromagnetic materials with zincblende structure, being compatible with current semiconductor technology, can be used to make high-performance spintronic devices. Here, we investigate electronic structures and magnetic properties of composite structure ((CrX)2 /(YX)2 (X=As, Sb; Se, Te and Y=Ga; Zn) superlattices) of zincblende half-metallic ferromagnetism and semiconductor by using Tran and Blaha's modified Becke and Johnson (mBJ) exchange potential. Calculated results show that they all are half-metallic ferromagnets with both generalized gradient approximation (GGA) and mBJ, and the total magnetic moment per formula unit follows a Slater-Pauling-like "rule of 8". The key half-metallic gaps by using mBJ are enhanced with respect to GGA results, which is because mBJ makes the occupied minority-spin p-bands move toward lower energy, but toward higher energy for empty minority-spin Cr-d bands. When the spin-orbit coupling (SOC) is included, the spin polarization deviates from 100%, and a most reduced polarization of 98.3% for (CrSb)2 /(GaSb)2, which indicates that SOC has small effects, of the order of 1%, in the considered four kinds of superlattice.

  7. In vitro effects of sodium hyaluronate on the proliferation and the apoptosis in chondrocytes from patients with Kashin-Beck disease and osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    Zongqiang Gao; Xiong Guo; Chen Duan; Weijuan Ma; Peng Xu; Ruiyu Liu; Qisheng Gu; Junchang Chen

    2009-01-01

    Objective:To identify the in vitro effects of sodium hyaluronate(HA) on the proliferation and the apoptosis of chondrocytes from patients with Kashin-Beck disease(KBD) and osteoarthritis(OA). Methods:Samples of articular cartilages from KBD and OA patients, as well as healthy volunteers(6 subjects in each of the 3 groups) were dissected, digested with collagenase and the cells cultured in monolayers. Chondrocytes from each sample were assigned to an untreated group and two HA-treated groups: H0(no HA), H100(HA, 0.1 g/L) and H500(HA, 0.5 g/L). The first passage chondrocytes were used to observe proliferation using the MTT assay, and apoptosis by flow cytometry through Annexin V/PI staining. Results:HA promoted proliferation of chondrocytes in all the three groups, and in KBD and OA groups, for cells cultured for 4 and 6 days, H500 significantly promoted the cell proliferation. The apoptotic rates of both KBD and OA group chondrocytes were in the order H500 < HA100 < H0. Conclusion:Sodium hyaluronate administration has a dose-dependendent vitro effect to promote proliferation and inhibit apoptosis of chondrocytes from patients with KBD and OA.

  8. Insights in the electronic structure and redox reaction energy in LiFePO4 battery material from an accurate Tran-Blaha modified Becke Johnson potential

    International Nuclear Information System (INIS)

    The main goals of this paper are to investigate the accuracy of the Tran-Blaha modified Becke Johnson (TB-mBJ) potential to predict the electronic structure of lithium iron phosphate and the related redox reaction energy with the lithium deintercalation process. The computed electronic structures show that the TB-mBJ method is able to partially localize Fe-3d electrons in LiFePO4 and FePO4 which usually is a problem for the generalized gradient approximation (GGA) due to the self interaction error. The energy band gap is also improved by the TB-mBJ calculations in comparison with the GGA results. It turned out, however, that the redox reaction energy evaluated by the TB-mBJ technique is not in good agreement with the measured one. It is speculated that this disagreement in the computed redox energy and the experimental value is due to the lack of a formal expression to evaluate the exchange and correlation energy. Therefore, the TB-mBJ is an efficient method to improve the prediction of the electronic structures coming form the standard GGA functional in LiFePO4 and FePO4. However, it does not appear to have the same efficiency for evaluating the redox reaction energies for the investigated system

  9. Near-edge band structures and band gaps of Cu-based semiconductors predicted by the modified Becke-Johnson potential plus an on-site Coulomb U

    International Nuclear Information System (INIS)

    Diamond-like Cu-based multinary semiconductors are a rich family of materials that hold promise in a wide range of applications. Unfortunately, accurate theoretical understanding of the electronic properties of these materials is hindered by the involvement of Cu d electrons. Density functional theory (DFT) based calculations using the local density approximation or generalized gradient approximation often give qualitative wrong electronic properties of these materials, especially for narrow-gap systems. The modified Becke-Johnson (mBJ) method has been shown to be a promising alternative to more elaborate theory such as the GW approximation for fast materials screening and predictions. However, straightforward applications of the mBJ method to these materials still encounter significant difficulties because of the insufficient treatment of the localized d electrons. We show that combining the promise of mBJ potential and the spirit of the well-established DFT + U method leads to a much improved description of the electronic structures, including the most challenging narrow-gap systems. A survey of the band gaps of about 20 Cu-based semiconductors calculated using the mBJ + U method shows that the results agree with reliable values to within ±0.2 eV

  10. Understanding ferromagnetism and optical absorption in 3d transition metal-doped cubic ZrO2 with the modified Becke-Johnson exchange-correlation functional

    International Nuclear Information System (INIS)

    The electronic structure, magnetic, and optical properties in cubic crystalline phase of Zr1−xTMxO2 (TM = V, Mn, Fe, and Co) at x = 6.25% are studied using density functional theory with the Generalized Gradient Approximation and the modified Becke-Johnson of the exchange-correlation energy and potential. In our calculations, the zirconia is a p-type semiconductor and has a large band gap. We evaluated the possibility of long-range magnetic order for transition metal ions substituting Zr. Our results show that ferromagnetism is the ground state in V, Mn, and Fe-doped ZrO2 and have a high value of energy in Mn-doped ZrO2. However, in Co-doped ZrO2, antiferromagnetic ordering is more stable than the ferromagnetic one. The exchange interaction mechanism has been discussed to explain the responsible of this stability. Moreover, it has been found that the V, Mn, and Fe transition metals provide half-metallic properties considered to be the leading cause, responsible for ferromagnetism. Furthermore, the optical absorption spectra in the TM -doped cubic ZrO2 are investigated

  11. Electronic structure of antifluorite Cu2X (X = S, Se, Te) within the modified Becke-Johnson potential plus an on-site Coulomb U

    International Nuclear Information System (INIS)

    The traditional photon absorbers Cu2−xX (X = S, Se, and Te) have regained significant research attention in the search of earth-abundant photovoltaic materials. These moderate- and narrow-gap materials have also been shown to exhibit excellent thermoelectric properties recently. However, semimetallic band structures with inverted band orderings are predicted for antifluorite structure Cu2X using density functional theory with the local density approximation or the generalized gradient approximation. We find that semiconducting band structures and normal band orderings can be obtained using the modified Becke-Johnson potential plus an on-site Coulomb U (the mBJ+U approach), which is consistent with our earlier finding for diamond-like Cu-based multinary semiconductors [Y. Zhang, J. Zhang, W. Gao, T. A. Abtew, Y. Wang, P. Zhang, and W. Zhang, J. Chem. Phys. 139, 184706 (2013)]. The trend of the chemical bonding of Cu2X is analyzed, which shows that the positions of the valence band maximum and conduction band minimum are strongly affected by the inter-site pd and intra-site sp hybridizations, respectively. The calculated gaps of Cu2S and Cu2Se still seem to be underestimated compared with experimental results. We also discuss the effects of different structural phases and Cu disordering and deficiency on the bandgaps of these materials

  12. Depressive symptoms in people with and without alcohol abuse: factor structure and measurement invariance of the Beck Depression Inventory (BDI-II across groups.

    Directory of Open Access Journals (Sweden)

    Cecilie Skule

    Full Text Available This study explored differences in the factor structure of depressive symptoms in patients with and without alcohol abuse, and differences in the severity of depressive symptoms between the two groups. In a sample of 358 patients without alcohol problems and 167 patients with comorbid alcohol problems, confirmatory factor analysis revealed that the same factor structures, Beck et al.'s two-factor Somatic Affective-Cognitive (SA-C model, and Buckley et al.'s three-factor Cognitive-Affective- Somatic (C-A-S model, demonstrated the best fit to the data in both groups. The SA-C model was preferred due to its more parsimonious nature. Evidence for strict measurement invariance across the two groups for the SA-C model was found. MIMIC (multiple-indicator-multiple-cause modeling showed that the level of depressive symptoms was found to be highest on both factors in the group with comorbid alcohol problems. The magnitude of the differences in latent mean scores suggested a moderate difference in the level of depressive symptoms between the two groups. It is argued that patients with comorbid depression and alcohol abuse should be offered parallel and adequate treatment for both conditions.

  13. First principles phase transition, elastic properties and electronic structure calculations for cadmium telluride under induced pressure: density functional theory, LDA, GGA and modified Becke-Johnson potential

    Science.gov (United States)

    Kabita, Kh; Maibam, Jameson; Indrajit Sharma, B.; Brojen Singh, R. K.; Thapa, R. K.

    2016-01-01

    We report first principles phase transition, elastic properties and electronic structure for cadmium telluride (CdTe) under induced pressure in the light of density functional theory using the local density approximation (LDA), generalised gradient approximation (GGA) and modified Becke-Johnson (mBJ) potential. The structural phase transition of CdTe from a zinc blende (ZB) to a rock salt (RS) structure within the LDA calculation is 2.2 GPa while that within GGA is found to be at 4 GPa pressure with a volume collapse of 20.9%. The elastic constants and parameters (Zener anisotropy factor, Shear modulus, Poisson’s ratio, Young’s modulus, Kleinmann parameter and Debye’s temperature) of CdTe at different pressures of both the phases have been calculated. The band diagram of the CdTe ZB structure shows a direct band gap of 1.46 eV as predicted by mBJ calculation which gives better results in close agreement with experimental results as compared to LDA and GGA. An increase in the band gap of the CdTe ZB phase is predicted under induced pressure while the metallic nature is retained in the CdTe RS phase.

  14. Psychometric properties of the Portuguese version of the State-Trait Anxiety Inventory applied to college students: factor analysis and relation to the Beck Depression Inventory

    Directory of Open Access Journals (Sweden)

    L. Andrade

    2001-03-01

    Full Text Available The psychometric properties of the Portuguese version of the trait form of the State-Trait Anxiety Inventory (STAI-T and its relation to the Beck Depression Inventory (BDI were evaluated in a large Brazilian college student sample containing 845 women and 235 men. STAI-T scores tended to be higher for women, singles, those who work, and subjects under 30 years. Factor analysis of the STAI-T for total sample and by gender yielded two factors: the first representing a mood dimension and the second being related to worrying or cognitive aspects of anxiety. In order to study the relation between anxiety and depression measures, factor analysis of the combination of the 21 BDI items and the 20 STAI-T items was also carried out. The analysis resulted in two factors that were analyzed according to the tripartite model of anxiety and depression. Most of the BDI items (measuring positive affectivity and nonspecific symptoms of depression were loaded on the first factor and four STAI-T items that measure positive affectivity. The remaining STAI-T items, all of them measuring negative affect, remained in the second factor. Thus, factor 1 represents a depression dimension and factor 2 measures a mood-worrying dimension. The findings of this study suggest that, although widely used as an anxiety scale, the STAI-T in fact measures mainly a general negative affect.

  15. Safe cycling!

    CERN Document Server

    Anaïs Schaeffer

    2012-01-01

    The HSE Unit will be running a cycling safety campaign at the entrances to CERN's restaurants on 14, 15 and 16 May. Pop along to see if they can persuade you to get back in the saddle!   With summer on its way, you might feel like getting your bike out of winter storage. Well, the HSE Unit has come up with some original ideas to remind you of some of the most basic safety rules. This year, the prevention campaign will be focussing on three themes: "Cyclists and their equipment", "The bicycle on the road", and "Other road users". This is an opportunity to think about the condition of your bike as well as how you ride it. From 14 to 16 May, representatives of the Swiss Office of Accident Prevention and the Touring Club Suisse will join members of the HSE Unit at the entrances to CERN's restaurants to give you advice on safe cycling (see box). They will also be organising three activity stands where you can test your knowle...

  16. [Rolf Hammel-Kiesow. Der Lübecker Katasterplan des 19. Jahrhunderts als historische Quelle. Überlegungen zur Stadtentwicklung Lübecks aus archäologischer, historischer und bauhistorischen Zicht] / Dennis Hormuth

    Index Scriptorium Estoniae

    Hormuth, Dennis

    2013-01-01

    Arvustus : Rolf Hammel-Kiesow. Der LÜbecker Katasterplan des 19. Jahrhunderts als historische Quelle. Überlegungen zur Stadtentwicklung Lübecks aus archäologischer, historischer und bauhistorischen Sicht. In: Stadtgründung und Stadterweiterung. Beiträge von Archäologie und Stadtgeschichtsforschung (=Beiträge zur Geschichte der Städte Mitteleuropas XXII). Linz, 2011. S. 75-104

  17. Rendimiento diagnóstico y estructura factorial del Inventario de Depresión de Beck-II (BDI-II

    Directory of Open Access Journals (Sweden)

    Jesús Sanz

    2013-01-01

    Full Text Available Este estudio tenía dos objetivos. Primero, analizar el rendimiento diagnóstico de la versión española del Inventario de Depresión de Beck-II (BDI-II en una muestra de pacientes con trastornos psicológicos y, segundo, examinar si las soluciones unifactoriales y bifactoriales del BDI-II encontradas previamente en muestras similares son replicables y, de ser así, analizar la contribución relativa del factor general y de los dos factores específicos a la varianza del BDI-II. El BDI-II, junto con el módulo de los trastornos del estado de ánimo de la Entrevista Clínica Estructurada para los Trastornos del Eje I del DSM-IV (SCID-I VC y un listado de cotejo de síntomas depresivos completado por el clínico, fueron aplicados a una muestra española de 322 pacientes adultos ambulatorios con diversos trastornos psicológicos. Tomando como criterio el diagnóstico clínico basado en la SCID-I VC y el listado de cotejo de síntomas depresivos, el BDI-II demostró un rendimiento diagnóstico aceptable para discriminar entre pacientes con trastorno depresivo mayor y pacientes sin depresión. Los análisis factoriales indicaron que el BDI-II mide una dimensión general de depresión compuesta por dos factores relacionados (somático y cognitivo, pero estos factores apenas explicaban varianza adicional más allá de la puntuación global.

  18. The electronic structure and optical properties of XSi(X = Fe,Ru,Os): A first principles investigation within the modified Becke-Johnson exchange potential plus LDA

    Energy Technology Data Exchange (ETDEWEB)

    Li Jia, E-mail: jiali@hebut.edu.cn; Zhang Zhidong; Ji Qing; Zhang Hui; Luo Hongzhi

    2012-10-05

    Highlights: Black-Right-Pointing-Pointer Reproduce of band gap for XSi(X = Fe,Ru,Os) with gap of {approx}10{sup -1} eV. Black-Right-Pointing-Pointer Using the mBJ + LDA first principles in comparison with GGA and LDA. Black-Right-Pointing-Pointer Theoretical optical conductivity is in agreement with the measurement. - Abstract: The electronic structure, optical reflectivity spectra and optical conductivity of semiconducting transition-metal silicides FeSi, RuSi and OsSi have been investigated by using first principles calculation within the recent developed modified Becke-Johnson exchange potential plus local-density approximation (mBJ + LDA). The electronic structures produced by mBJ + LDA, generalized gradient approximation (GGA) and LDA are rather similar although the band gap has been enlarged more or less by the mBJ + LDA compared to the GGA and LDA for the three compounds. The mBJ + LDA, GGA and LDA all have overestimated the band gap for FeSi and OsSi compared to the experiment. For RuSi, the theoretical gap values are basically close to the experimental values and the improvement of gap by mBJ + LDA is only 0.04 eV in comparison with the GGA. The mBJ + LDA and GGA also produce similar results with respect to their optical properties including the reflectivity spectra and optical conductivity except that for the reflectivity spectra of FeSi, the GGA result is little better consistent with the experimental measurement than the mBJ + LDA result. The optical conductivity calculated by mBJ + LDA and GGA both exhibits the absorption edge, in well correspondence to the optical measurement.

  19. En kommentar til Becks model

    DEFF Research Database (Denmark)

    Philipps, Morten; Andersen, Thomas Dyreborg

    2014-01-01

    Flipped classroom – en trend vi må forholde os til Online læringsressourcer har de sidste par år fået mange til at indse at teknologien har noget radikalt andet at byde på, og dette har skabt en populær didaktik kaldet flipped classroom som vi både ser vinde indpas i folkeskolen og på...... Professionshøjskolen Metropol hvor vi er ansat. Kommentaren her retter sig mod en tidligere bragt artikel i MONA, “Det virtuelle læringsrums topologi” af Claus Jessen. Vi argumenterer for at den didaktiske model flipped classrooms brug af video, frem for tavleundervisning, kan frigøre undervisningstid til at arbejde...

  20. Kriisi fataalne oht / Ulrich Beck

    Index Scriptorium Estoniae

    Beck, Ulrich

    2009-01-01

    Sotsioloogi arvates peitub praeguses majanduskriisis võimalus tuua Euroopa Liit uutele alustele, võttes aluseks printsiibi, et poliitika on rahvuslikul tasemel seda edukam, mida euroopalikum, kosmopoliitlikum ta on

  1. Study of wurtzite and zincblende GaN/InN based solar cells alloys: First-principles investigation within the improved modified Becke-Johnson potential

    KAUST Repository

    Ul Haq, Bakhtiar

    2014-09-01

    Wurtzite GaInN alloys with flexible energy gaps are pronounced for their potential applications in optoelectronics and solar cell technology. Recently the unwanted built-in fields caused by spontaneous polarization and piezoelectric effects in wurtzite (WZ) GaInN, has turned the focus towards zinc-blende (ZB) GaInN alloys. To comprehend merits and demerits of GaInN alloys in WZ and ZB structures, we performed a comparative study of the structural, electronic and optical properties of Ga1-xInxN alloys with different In concentration using first-principles methodology with density function theory with generalized gradient approximations (GGA) and modified Becke-Johnson (mBJ) potential. Investigations pertaining to total energy of GaInN for the both phases, demonstrate a marginal difference, reflecting nearly equivalent stability of the ZB-GaInN to WZ-GaInN. The larger ionic radii of indium (In), result in larger values of lattice parameters of Ga1-xInxN with higher In concentration. For In deficient Ga1-xInxN, at first, the formation enthalpies increase rapidly as the In content approaches to 45% in WZ and 47% in ZB, and then decreases with the further increase in In concentration. ZB-Ga1-xInxN alloys exhibit comparatively narrower energy gaps than WZ, and get smaller with increase in In contents. The smaller values of effective masses of free carriers, in WZ phase, than ZB phase, reflect higher carrier mobility and electrical conductivity of WZ-Ga1-xInxN. Moreover wide energy gap of WZ-Ga1-xInxN results in large values of the absorption coefficients comparatively and smaller static refractive indices compared to ZB-Ga1-xInxN. Comparable electronic and optical characteristics of the ZB-Ga1-xInxN to WZ-Ga1-xInxN endorses it a material of choice for optoelectronics and solar cell applications besides the WZ-Ga1-xInxN. © 2014 Elsevier Ltd.

  2. The relevance of food composition data for nutrition surveys in rural Tibet: pilot study in the context of Kashin-Beck Disease

    Directory of Open Access Journals (Sweden)

    Dermience, M.

    2013-01-01

    Full Text Available Kashin-Beck disease (KBD is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People's Republic of China. The etiology of the disease remains obscure although environmental factors are assumed to be involved. Diet, in particular, differentiates the rural community, affected by KBD, from the other communities (nomads and city-dwellers, who remain unaffected. In anticipation of a nutrition survey, this study aimed to measure the mineral content (Ca, P, Mg, Fe, Zn, Mn, Cu, Ni, Se, Al, Sr, Mo, Cd, As, Pb, Hg, Cr, and Co of eight Tibetan staple foods and to compare the results against two food composition tables (FCTs. Foods were sampled in twenty households selected from both an endemic and a non-endemic area of rural Tibet. Ten minerals involved in bone metabolism were measured using atomic and molecular spectrometric methods. Results revealed that a very limited number of food/constituent pairs showed a variation in mineral composition during a single year of testing for a given region. In addition, results showed significant differences in mineral content between the endemic and the non-endemic area, especially for wheat flour. Following our analysis of the mineral content of the Tibetan food samples, results were statistically compared with similar foods listed in two food composition tables: the USDA National Nutrient Database (USDA Food Search for Windows, Version 1.0, database version SR23, and the China Food Composition Table (book 1, 2nd edition. More than 50 to 60% of p-values < 0.05 were highlighted, suggesting the inappropriateness of using FCTs as a reference for nutrition surveys in rural Tibet, and emphasizing the need for analysis of traditional foods. Differences were found to be more or less marked depending on the element considered, and calcium content seemed to show the greatest difference. Although it is obviously too early for definite

  3. Relationship between short humerus disease and Kashin Beck disease in Kaschin-Beck disease areas in Tibet%西藏大骨节病病区肱骨短小症与大骨节病关系的分析

    Institute of Scientific and Technical Information of China (English)

    李群伟; 龚弘强

    2016-01-01

    Three new points of view were reported in this study:1.Found out the distribution of KaschinBeck disease (KBD) in Tibet,the complexity of bone disease composition,and the types of osteopathy coexisted which need to be identified;2.The clinical symptoms of KBD in Tibet were significantly different from those in other areas of our country;3.The new clinical subtypes of KBD were found in Tibet,which had humeral shortness and short stature,but with normal hands and feet.This discovery made us understand KBD more profoundly and comprehensively,and promoted the research and prevention work of KBD.%作者报告三个全新的观点:1.西藏大骨节病病区骨病构成十分复杂,有多种骨病并存,应注意鉴别;2.西藏大骨节病的临床表现与内地有本质区别;3.在西藏存在大骨节病新的临床亚型,即以“肱骨短小、身材矮小和手足正常”为主要临床表现的特殊类型.本发现使得对大骨节病的认识更为深刻而全面,对大骨节病的研究和防治具有重要意义.

  4. Validation of the Brazilian Portuguese version of the Beck Depression Inventory-II in a community sample Validação da versão brasileira em português do Inventário de Depressão de Beck-II numa amostra da comunidade

    Directory of Open Access Journals (Sweden)

    Marcio Henrique Gomes-Oliveira

    2012-12-01

    Full Text Available BACKGROUND: The Beck Depression Inventory (BDI is used worldwide for detecting depressive symptoms. This questionnaire has been revised (1996 to match the DSM-IV criteria for a major depressive episode. We assessed the reliability and the validity of the Brazilian Portuguese version of the BDI-II for non-clinical adults. METHODS: The questionnaire was applied to 60 college students on two occasions. Afterwards, 182 community-dwelling adults completed the BDI-II, the Self-Report Questionnaire, and the K10 Scale. Trained psychiatrists performed face-to-face interviews with the respondents using the Structured Clinical Interview (SCID-I, the Montgomery-Åsberg Depression Scale, and the Hamilton Anxiety Scale. Descriptive analysis, signal detection analysis (Receiver Operating Characteristics, correlation analysis, and discriminant function analysis were performed to investigate the psychometric properties of the BDI-II. RESULTS: The intraclass correlation coefficient of the BDI-II was 0.89, and the Cronbach's alpha coefficient of internal consistency was 0.93. Taking the SCID as the gold standard, the cut-off point of 10/11 was the best threshold for detecting depression, yielding a sensitivity of 70% and a specificity of 87%. The concurrent validity (a correlation of 0.63-0.93 with scales applied simultaneously and the predictive ability of the severity level (over 65% correct classification were acceptable. CONCLUSION: The BDI-II is reliable and valid for measuring depressive symptomatology among Portuguese-speaking Brazilian non-clinical populations.OBJETIVOS: O Inventário de Depressão de Beck (IDB é utilizado mundialmente para detectar sintomas depressivos. Este questionário foi revisado (1996 para se adequar aos critérios do DSM-IV para episódio depressivo maior. Avaliamos a confiabilidade e validade da versão I em português-brasileiro do IDB-I em uma amostra não clínica de adultos. MÉTODOS: O questionário foi aplicado em duas

  5. An Improved Study of Electronic Band Structure and Optical Parameters of X-Phosphides (X--B, AL, Ga, In) by Modified Becke-Johnson Potential%An Improved Study of Electronic Band Structure and Optical Parameters of X-Phosphides (X--B, AL, Ga, In) by Modified Becke-Johnson Potential

    Institute of Scientific and Technical Information of China (English)

    Masood Yousaf; M.A. Saeed; R. Ahmed; M.M. Alsardia; Ahmad Radzi Mat Isa; A. Shaari

    2012-01-01

    We report the electronic band structure and optical parameters of X-Phosphides (X=B, AI, Ga, In) by first-principles technique based on a new approximation known as modified Becke-Johnson (roB J). This potential is considered more accurate in elaborating excited states properties of insulators and semiconductors as compared to LDA and GGA. The present calculated band gaps values of BP, AlP, GaP, and InP are 1.867 eV, 2.268 eV, 2.090 eV, and 1.377 eV respectively, which are in close agreement to the experimental results. The band gap values trend in this study is as: E9 (mBJ-GGA/LDA) 〉 E9 (GGA) 〉 Eg (LDA). Optical parametric quantities (dielectric constant, refractive index, reflectivity and optical conductivity) which based on the band structure are aiso presented and discussed. BP, AlP, GaP, and InP have strong absorption in between the energy range 4-9 eV, 4-7 ev, 3-7 eV, and 2-7 eV respectively. Static dielectric constant, static refractive index and coefficient of reflectivity at zero frequency, within mBJ-GGA, are also calculated. BP, AIP, GaP, and InP show significant optical conductivity in the range 5.2-10 eV, 4.3-8 eV, 3.5- 7.2 eV, and 3.2-8 eV respectively. The present study endorses that the said compounds can be used in opto-electronic applications, for different energy ranges.

  6. Extraction of Phenylethanoid Glucosides in Cistanches salsa Beck and It Application in Cigarette%肉苁蓉中苯乙醇糖苷提取及在卷烟中的应用研究

    Institute of Scientific and Technical Information of China (English)

    赵秋蓉; 吴迪; 祖萌萌; 纪旭东; 张峻松

    2012-01-01

    考察了乙醇浓度、提取时间、提取温度对肉苁蓉提取量的影响。实验结果表明:肉苁蓉提取量随着乙醇浓度的升高先是逐渐升高然后又呈现下降的趋势;当乙醇浓度和提取温度一定时,肉苁蓉提取得率随提取时间的延长而增加,当固定肉苁蓉的提取时间和提取用乙醇的浓度,肉苁蓉提取随着提取温度的增加,通过实验表明肉苁蓉提取条件为:乙醇浓度为70%,提取时间为4h,提取温度为70℃。以V(乙酸乙酯):V(甲醇)=15:1的混合溶剂为洗脱剂,用柱层析法分离得到苯乙醇糖苷。通过卷烟加香试验发现,肉苁蓉苯乙醇糖苷能有效地掩盖卷烟杂气,使烟气柔和、余味舒适、回甜感好、香气细腻,对改进烟气质量作用明显。%The affluence of alcohol concentration, extraction time and extraction temperature on the yield of the Cistanches salsa Beck were investigated. The yield of the Cistanches salsa Beck increased with the concentration of alcohol increasing at first, and then decreased as the alcohol concentration keep on increasing. The yield also increased with the extraction time when the alcohol concentration and extraction h temperature were fixed. As the alcohol concentration and extraction time were 4h. The optimum technology of extracting Cistanches salsa Beck was as follows: The extraction time is 4h, the extraction temperature is 70℃ and the alcohol concentration is 70%. The phenylethanoid glucosides in Cistanches salsa Beck were separated with column chromatography, and use V ( ethyl acetate ) :V ( methyl alcohol ) =15:1 for eluent. The phenylethanoid glucosides of Cistanches salsa Beck was applied in cigarettes as tobacco flavorant. The results indicated that it could efficiently reduce offensive odor, make tobacco smoke smooth and fine, and improve smoking quality of the cigarettes.

  7. Essays on economic cycles

    NARCIS (Netherlands)

    Groot, de E.A. (Bert)

    2006-01-01

    Schumpeter’s line of thought of multiple economic cycles is further investigated. The existence of multiple cycles in economic variables is demonstrated. In basic innovations five different cycles are found. Multiple cycle structures are shown in various macro-economic variables from the United King

  8. The business cycle and the life cycle

    OpenAIRE

    Paul Gomme; Richard Rogerson; Peter Rupert; Randall Wright

    2004-01-01

    The paper documents how cyclical fluctuations in market work vary over the life cycle and then assesses the predictions of a life-cycle version of the growth model for those observations. The analysis yields a simple but striking finding. The main discrepancy between the model and that data lies in the inability of the model to account for fluctuations in hours for individuals in the first half of their life cycle. The predictions for those in the latter half of the life cycle are quite close...

  9. The Solar Cycle

    CERN Document Server

    Hathaway, David H

    2015-01-01

    The Solar Cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. A number of other solar activity indicators also vary in association with the sunspots including; the 10.7cm radio flux, the total solar irradiance, the magnetic field, flares and coronal mass ejections, geomagnetic activity, galactic cosmic ray fluxes, and radioisotopes in tree rings and ice cores. Individual solar cycles are characterized by their maxima and minima, cycle periods and amplitudes, cycle shape, the equatorward drift of the active latitudes, hemispheric asymmetries, and active longitudes. Cycle-to-cycle variability includes the Maunder Minimum, the Gleissberg Cycle, and the Gnevyshev-Ohl (even-odd) Rule. Short-term variability includes the 154-day periodicity, quasi-biennial variations, and double-peaked maxima. We conclude with an examination of prediction techniques for the solar cycle and a closer look at cycles 23 and 24.

  10. 基质金属蛋白酶与大骨节病的相关性研究%Correlation of matrix metalloproteinases and Kashin-Beck disease

    Institute of Scientific and Technical Information of China (English)

    陈静宏; 曹峻岭; 王治伦; 马天有; 王梦莹; 何颖; 杨占田; 陈晨

    2014-01-01

    目的:观察基质金属蛋白酶(Matrix metalloproteinases,MMPs)在大骨节病(Kashin-Beck disease, KBD)儿童软骨和低硒条件下T-2毒素中毒大鼠软骨中的表达,以及T-2毒素对软骨细胞MMP-13启动子的激活作用,探讨MMPs与KBD发病的关系。方法以5例尸检KBD儿童(KBD组)和5例因车祸死亡或畸形手术的正常儿童(对照组)手指节软骨为研究对象,采用免疫组织化学染色的方法,检测软骨中MMP-1和MMP-13的表达。雄性健康SD大鼠32只,按体质量采用随机数字表法分为常规饲料组、低硒饲料组,每组各16只。常规饲料硒含量为101.500μg/kg,低硒饲料硒含量为1.118μg/kg。大鼠低硒动物模型建造成功后,常规饲料组分为常规组和常规+T-2组,低硒饲料组分为低硒组和低硒+T-2组,每组8只。 T-2毒素(100μg·kg-1·d-1)灌胃饲养,30 d后处死大鼠,取左侧膝关节,用免疫组织化学染色方法检测大鼠关节软骨细胞MMP-1和MMP-13的表达水平。体外培养人软骨细胞系C28/I2细胞,分成空载体组、MMP-13启动子载体组、MMP-13启动子载体+T-2毒素20μg/L组、MMP-13启动子载体+T-2毒素40μg/L组,将-1602/+20-MMP13-Luc启动子重组荧光素酶报导质粒以及空载体瞬时转染C28/I2细胞,24 h后,加入20μg/L和40μg/L T-2毒素,继续培养24 h,用荧光素酶报告基因检测T-2毒素对MMP-13启动子的作用。结果 KBD组儿童关节软骨表层和中层MMP-1表达阳性率[(29.73±10.12)%、(28.27±0.91)%]均高于对照组[(2.47±0.11)%、(0.00±0.00)%,P均<0.05],KBD组儿童关节软骨表层和中层 MMP-13表达阳性率[(13.21±4.32)%、(41.85±6.32)%]明显高于对照组[(5.72±0.31)%、(0.00±0.00)%,P均<0.05]。低硒+T-2毒素组大鼠关节软骨MMP-13在表层和中层表达水平[(13.21±4.32)%、61.85±8.68)%]明显高于常规组和低硒组[(2.43±0.22

  11. Solar cycle 25: another moderate cycle?

    CERN Document Server

    Cameron, Robert H; Schuessler, Manfred

    2016-01-01

    Surface flux transport simulations for the descending phase of cycle 24 using random sources (emerging bipolar magnetic regions) with empirically determined scatter of their properties provide a prediction of the axial dipole moment during the upcoming activity minimum together with a realistic uncertainty range. The expectation value for the dipole moment around 2020 $(2.5\\pm1.1\\,$G) is comparable to that observed at the end of cycle 23 (about $2\\,$G). The empirical correlation between the dipole moment during solar minimum and the strength of the subsequent cycle thus suggests that cycle 25 will be of moderate amplitude, not much higher than that of the current cycle. However, the intrinsic uncertainty of such predictions resulting from the random scatter of the source properties is considerable and fundamentally limits the reliability with which such predictions can be made before activity minimum is reached.

  12. Solar Cycle 25: Another Moderate Cycle?

    Science.gov (United States)

    Cameron, R. H.; Jiang, J.; Schüssler, M.

    2016-06-01

    Surface flux transport simulations for the descending phase of Cycle 24 using random sources (emerging bipolar magnetic regions) with empirically determined scatter of their properties provide a prediction of the axial dipole moment during the upcoming activity minimum together with a realistic uncertainty range. The expectation value for the dipole moment around 2020 (2.5 ± 1.1 G) is comparable to that observed at the end of Cycle 23 (about 2 G). The empirical correlation between the dipole moment during solar minimum and the strength of the subsequent cycle thus suggests that Cycle 25 will be of moderate amplitude, not much higher than that of the current cycle. However, the intrinsic uncertainty of such predictions resulting from the random scatter of the source properties is considerable and fundamentally limits the reliability with which such predictions can be made before activity minimum is reached.

  13. Cycling in Sydney, Australia

    Directory of Open Access Journals (Sweden)

    Alexis Zander

    2013-01-01

    Full Text Available Introduction. Cycling can be an enjoyable way to meet physical activity recommendations and is suitable for older people; however cycling participation by older Australians is low. This qualitative study explored motivators, enablers, and barriers to cycling among older people through an age-targeted cycling promotion program. Methods. Seventeen adults who aged 50–75 years participated in a 12-week cycling promotion program which included a cycling skills course, mentor, and resource pack. Semistructured interviews at the beginning and end of the program explored motivators, enablers, and barriers to cycling. Results. Fitness and recreation were the primary motivators for cycling. The biggest barrier was fear of cars and traffic, and the cycling skills course was the most important enabler for improving participants’ confidence. Reported outcomes from cycling included improved quality of life (better mental health, social benefit, and empowerment and improved physical health. Conclusions. A simple cycling program increased cycling participation among older people. This work confirms the importance of improving confidence in this age group through a skills course, mentors, and maps and highlights additional strategies for promoting cycling, such as ongoing improvement to infrastructure and advertising.

  14. Life cycle assessment (LCA)

    DEFF Research Database (Denmark)

    Thrane, Mikkel; Schmidt, Jannick Andresen

    2004-01-01

    The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards.......The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards....

  15. Adaptación española del Inventario para la Depresión de Beck-II (BDI-II: 3. Propiedades psicométricas en pacientes con trastornos psicológicos

    Directory of Open Access Journals (Sweden)

    JESÚS SANZ

    2005-01-01

    Full Text Available Se presentan datos sobre la fiabilidad y validez de la adaptación española del Inventario para la Depresión de Beck-II (BDI-II; Beck, Steer y Brown, 1996, obtenidos con una muestra de 305 pacientes ambulatorios con diversos diagnósticos psicopatológicos según el DSM-IV. El coeficiente alfa de fiabilidad fue alto (alfa = 0,89. Las correlaciones con otras medidas autoaplicadas y heteroaplicadas de depresión fueron elevadas y significativamente mayores que la correlación con una medida de ansiedad, lo que avala la validez convergente y discriminante del BDI-II, respectivamente. Respecto a la validez de criterio, los resultados demostraron que los pacientes diagnosticados con un trastorno depresivo mayor tenían niveles de depresión más elevados, medidos con el BDI-II, que los pacientes de otros grupos diagnósticos, aunque no hubo diferencias con los pacientes con trastornos de personalidad. Finalmente, la validación factorial del BDI-II proporcionó una solución bifactorial (factor somático- motivacional y factor cognitivo que coincide con la hallada en estudios previos. Se concluye que el BDI es un instrumento válido de detección y cuantificación de síntomas depresivos en pacientes, si bien su utilidad como herramienta para el diagnóstico diferencial de la depresión es una cuestión pendiente de investigación.

  16. HIV Life Cycle

    Science.gov (United States)

    HIV Overview The HIV Life Cycle (Last updated 9/22/2015; last reviewed 9/22/2015) Key Points HIV gradually destroys the immune ... life cycle. What is the connection between the HIV life cycle and HIV medicines? Antiretroviral therapy (ART) ...

  17. Cycling To Awareness.

    Science.gov (United States)

    Kozak, Stan

    1999-01-01

    Encourages environmental and outdoor educators to promote bicycling. In the community and the curriculum, cycling connects environmental issues, health and fitness, law and citizenship, appropriate technology, and the joy of being outdoors. Describes the Ontario Cycling Association's cycling strategy and its four components: school cycling…

  18. The Solar Cycle

    Directory of Open Access Journals (Sweden)

    David H. Hathaway

    2015-09-01

    Full Text Available The solar cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. A number of other solar activity indicators also vary in association with the sunspots including; the 10.7 cm radio flux, the total solar irradiance, the magnetic field, flares and coronal mass ejections, geomagnetic activity, galactic cosmic ray fluxes, and radioisotopes in tree rings and ice cores. Individual solar cycles are characterized by their maxima and minima, cycle periods and amplitudes, cycle shape, the equatorward drift of the active latitudes, hemispheric asymmetries, and active longitudes. Cycle-to-cycle variability includes the Maunder Minimum, the Gleissberg Cycle, and the Gnevyshev–Ohl (even-odd Rule. Short-term variability includes the 154-day periodicity, quasi-biennial variations, and double-peaked maxima. We conclude with an examination of prediction techniques for the solar cycle and a closer look at cycles 23 and 24.

  19. [Cycling in Zagreb].

    Science.gov (United States)

    Matos, Stipan; Krapac, Ladislav; Krapac, Josip

    2007-01-01

    Cycling in Zagreb, as means of urban transport inside and outside the city, has a bright past, hazy presence but a promising future. Every day, aggressive citizens who lack urban traffic culture mistreat many cyclists but also many pedestrians. Sedentary way of living, unhealthy eating habits and inadequate recreation would surely be reduced if Zagreb had a network of cycling tracks (190 cm) or lanes (80 cm). Main city roads were constructed at the beginning of the 20th century. Today, the lack of cycling tracks is particularly evident in terms of missing connections between northern and southern parts of the city. Transportation of bikes in public vehicles, parking of bikes as well as cycling along the foot of the mountains Medvednica and Zumberacko gorje is not adequately organized. Better organization is necessary not only because of the present young generation but also because of the young who will shortly become citizens of the EU, where cycling is enormously popular. Cycling tourism is not known in Zagreb, partly due to inadequate roads. The surroundings of Zagreb are more suitable for cycling tourism and attractive brochures and tourist guides offer information to tourists on bikes. Professional, acrobatic and sports cycling do not have a tradition in Zagreb and in Croatia. The same holds true for recreational cycling and indoor exercise cycling. The authors discuss the impact of popularization of cycling using print and electronic media. The role of district and local self-government in the construction and improvement of traffic roads in Zagreb is very important. It is also significant for the implementation of legal regulations that must be obeyed by all traffic participants in order to protect cyclists, the most vulnerable group of traffic participants besides passengers. Multidisciplinary action of all benevolent experts would surely increase safety and pleasure of cycling in the city and its surroundings. This would also help reduce daily stress and

  20. Real business cycle realizations

    OpenAIRE

    Smith, Gregor W.; Stanley E. Zin

    1997-01-01

    Much recent business cycle research focuses on moments of macroeconomic aggregates. We construct examples of real business cycle sample paths for output, consumption, and employment for the U.S. economy. Annual sample paths are generated from an initial condition in 1925, measured technology and government spending shocks since then, and a standard, calibrated, one-sector model of the business cycle. Quarterly sample paths are generated similarly, from an initial condition in 1955. The law of...

  1. Fictitious Supercontinent Cycles

    CERN Document Server

    Herndon, J Marvin

    2013-01-01

    Descriptions of phenomena, events, or processes made on the basis of problematic paradigms can be unreasonably complex (e.g. epicycles) or simply wrong (e.g. ultraviolet catastrophe). Supercontinent cycles, also called Wilson cycles, are, I submit, artificial constructs, like epicycles. Here I provide the basis for that assertion and describe published considerations from a fundamentally different, new, indivisible geoscience paradigm which obviate the necessity for assuming supercontinent cycles.

  2. Alternative fuel cycles

    International Nuclear Information System (INIS)

    Uranium resource utilization and economic considerations provide incentives to study alternative fuel cycles as future options to the PHWR natural uranium cycle. Preliminary studies to define the most favourable alternatives and their possible introduction dates are discussed. The important and uncertain components which influence option selection are reviewed, including nuclear capacity growth, uranium availability and demand, economic potential, and required technological developments. Finally, a summary of Ontario Hydro's program to further assess cycle selection and define development needs is given. (auth)

  3. Fast breeder fuel cycle

    International Nuclear Information System (INIS)

    Basic elements of the ex-reactor part of the fuel cycle (reprocessing, fabrication, waste handling and transportation) are described. Possible technical and proliferation measures are evaluated, including current methods of accountability, surveillance and protection. The reference oxide based cycle and advanced cycles based on carbide and metallic fuels are considered utilizing conventional processes; advanced nonaqueous reprocessing is also considered. This contribution provides a comprehensive data base for evaluation of proliferation risks

  4. Friction Generated Limit Cycles

    OpenAIRE

    Ohlsson, Henrik; Åström, Karl Johan

    2001-01-01

    This paper treats limit cycles caused by friction. The goal has been to explain phenomena that have been observed experimentally in mechatronic systems. Experiments have shown that oscillations of qualitatively different types can be obtained simply by changing controller specifications. Stiction is important in some cases but not in others. Necessary conditions for limit cycle are given for the case where stiction is important. Conditions for local stability of the limit cycles are also pres...

  5. Historicising the Hydrosocial Cycle

    OpenAIRE

    Jeremy J. Schmidt

    2014-01-01

    This paper examines the historical claims made in support of the hydrosocial cycle. In particular, it considers how arguments advancing the hydrosocial cycle make historical claims regarding modernist conceptions of what water is (i.e. H2O) and its fit with society. The paper gives special emphasis to the society/nature dualism and to the notion of agency as key sites of contest in arguments regarding the hydrosocial cycle. It finds that, while several versions of the hydrosocial cycle seek t...

  6. Edgeworth cycles revisited

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Joseph [MIT Sloan School of Management, 50 Memorial Drive, E52-447, Cambridge MA 02142 (United States); Muehlegger, Erich [John F. Kennedy School of Government, Harvard University, Mailbox 25, 79 JFK Street, Cambridge, MA 02138 (United States); Samphantharak, Krislert [Graduate School of International Relations and Pacific Studies, University of California at San Diego, 9500 Gilman Drive 1519, La Jolla, CA 92093 (United States)

    2010-05-15

    Some gasoline markets exhibit remarkable price cycles, where price spikes are followed by a series of small price declines: a pattern consistent with a model of Edgeworth cycles described by Maskin and Tirole. We extend the model and empirically test its predictions with a new dataset of daily station-level prices in 115 US cities. Consistent with the theory, and often in contrast with previous empirical work, we find the least and most concentrated markets are much less likely to exhibit cycling behavior both within and across cities; areas with more independent convenience-store gas stations are also more likely to cycle. (author)

  7. Adaptación española del Inventario para la Depresión de Beck-II (BDI-II: 2. Propiedades psicométricas en población general

    Directory of Open Access Journals (Sweden)

    JESÚS SANZ

    2003-01-01

    Full Text Available Se presentan por primera vez datos normativos y de fiabilidad y validez factorial de la adaptación española del Inventario para la Depresión de Beck-II (BDI-II; Beck, Steer y Brown, 1996 obtenidos con una muestra de 470 adultos seleccionados de la población general española. La fiabilidad de consistencia interna del BDI-II fue elevada (coeficiente alfa de 0,87. Los análisis factoriales indicaron que el BDI-II mide una dimensión general de depresión compuesta por dos factores altamente relacionados, uno cognitivo-afectivo y otro somático-motivacional. En términos de consistencia interna y validez factorial, el BDI-II parece mejor instrumento para evaluar sintomatología depresiva en población general que su predecesor, el BDI-IA. La distribución de la puntuación total del BDI-II fue similar a la encontrada en estudios previos, con una media superior en 2 puntos a la que se suele obtener con el BDI-IA, lo que justifica incrementar las puntuaciones para definir las categorías de gravedad de la depresión. Además, se hallaron diferencias significativas en tales puntuaciones en función del sexo, la edad, el nivel de educación y el estado civil: las mujeres puntuaban más alto que los varones, las personas mayores de 60 años más que las personas de menor edad, las personas con estudios básicos o sin estudios más que las personas con estudios secundarios o universitarios, y las personas divorciadas, separadas o viudas más que las personas casadas o conviviendo con una pareja. Se ofrecen puntuaciones normativas para la muestra total, y se discute su utilidad para evaluar la significación clínica de los resultados de los tratamientos contra la depresión.

  8. Teaching the Krebs Cycle.

    Science.gov (United States)

    Akeroyd, F. Michael

    1983-01-01

    Outlines a simple but rigorous treatment of the Krebs Cycle suitable for A-level Biology students. The importance of the addition of water molecules in various stages of the cycle is stressed as well as the removal of hydrogen atoms by the oxidizing enzymes. (JN)

  9. Life Cycle Environmental Management

    DEFF Research Database (Denmark)

    Pedersen, Claus Stig; Jørgensen, Jørgen; Pedersen, Morten Als

    1996-01-01

    processes. The discipline of life cycle environmental management (LCEM) focuses on the incorporation of environmental criteria from the life cycles of products and other company activities into the company management processes. This paper introduces the concept of LCEM as an important element...

  10. Life cycle management (LCM)

    DEFF Research Database (Denmark)

    Remmen, Arne; Thrane, Mikkel

    2004-01-01

    The chapter gives an introduction to Life Cycle Management (LCM) and shows how LCM can be practiced in different contexts and at different ambition levels.......The chapter gives an introduction to Life Cycle Management (LCM) and shows how LCM can be practiced in different contexts and at different ambition levels....

  11. Power Plant Cycling Costs

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, N.; Besuner, P.; Lefton, S.; Agan, D.; Hilleman, D.

    2012-07-01

    This report provides a detailed review of the most up to date data available on power plant cycling costs. The primary objective of this report is to increase awareness of power plant cycling cost, the use of these costs in renewable integration studies and to stimulate debate between policymakers, system dispatchers, plant personnel and power utilities.

  12. Predicting the Sunspot Cycle

    Science.gov (United States)

    Hathaway, David H.

    2009-01-01

    The 11-year sunspot cycle was discovered by an amateur astronomer in 1844. Visual and photographic observations of sunspots have been made by both amateurs and professionals over the last 400 years. These observations provide key statistical information about the sunspot cycle that do allow for predictions of future activity. However, sunspots and the sunspot cycle are magnetic in nature. For the last 100 years these magnetic measurements have been acquired and used exclusively by professional astronomers to gain new information about the nature of the solar activity cycle. Recently, magnetic dynamo models have evolved to the stage where they can assimilate past data and provide predictions. With the advent of the Internet and open data policies, amateurs now have equal access to the same data used by professionals and equal opportunities to contribute (but, alas, without pay). This talk will describe some of the more useful prediction techniques and reveal what they say about the intensity of the upcoming sunspot cycle.

  13. Assessing Cycling Participation in Australia

    OpenAIRE

    Chris Rissel; Cameron Munro; Adrian Bauman

    2013-01-01

    Planning and evaluating cycling programs at a national or state level requires accurate measures of cycling participation. However, recent reports of cycling participation have produced very different estimates. This paper examines the reported rates of cycling in five recent population surveys of cycling. Three surveys (one national and two from Sydney) asking respondents when they last rode a bicycle generated cycling participation (cycled in the past year) estimates of 29.7%, 34.1% and 28....

  14. Bimodality and the Hale cycle

    Science.gov (United States)

    Wilson, Robert M.

    1988-01-01

    Evidence is provided of a modulation of between 20 and 24 yr for the Hale cycle, and comparison of consecutive pairs of cycles strongly suggests that even-numbered cycles are preferentially paired with odd-numbered following cycles. The results indicate that cycles 22 and 23 form a new cyle pair. The sum of monthly mean sunspot numbers over consecutively paired sunspot cycles for Hale cycle 12 is found to be about 19,100 + or - 3000.

  15. The Anderson Quin Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J.H.; Bilbow, W.M.

    1993-03-18

    The objective of this study was to make a more refined evaluation of the Anderson Quin Cycle based on most recent information on the performance of various elements that will be used in the Anderson Quin Cycle. My original estimate of the work plan for evaluating and optimizing the Anderson Quin Cycle called for 7000 man hours of work. Since this grant was limited to 2150 man hours, we could not expect to achieve all the objectives within the allotted period of work. However, the most relevant program objectives have been completed as reported here. The analysis generally confirms the results originally estimated in my paper on the subject. (Ref. 2) Further optimizations should show even higher efficiencies. The Anderson Quin Cycle (US Patent applied for) basically consists of 5 elements in the power cycle: A refrigeration system to cool and clean the inlet air before it enters the compressor that supplies air for the gas turbine; a gas turbine consisting of a compressor, combustor, and turbine; a steam boiler and steam turbine system using the heat from the exhaust gas out of the gas turbine; a vapor turbine cycle, which utilizes the condensed heat from the exhaust of the steam turbine and the exhaust gas heat leaving the steam boiler to operate a vapor turbine cycle which utilizes another fluid than water, in this case isobutane; and the fifth element consists of a gas cooler and heat pump system, which removes the heat from the exhaust gas to lower its temperature essentially to atmospheric temperature, and at the same time permits treatment of the exhaust gas to remove acid components such as sulfur dioxide and nitrogen oxides. Current industry accepted component characteristics were incorporated in the performance analysis of the overall cycle, ensuring accurate and meaningful operating predictions. The characteristics and performance of each of the elements are described. The thermal efficiency of the optimized calculated Anderson Quin Cycle is 62 percent.

  16. Future fuel cycles

    International Nuclear Information System (INIS)

    A fuel cycle must offer both financial and resource savings if it is to be considered for introduction into Ontario's nuclear system. The most promising alternative CANDU fuel cycles are examined in the context of both of these factors over a wide range of installed capacity growth rates and economic assumptions, in order to determine which fuel cycle, or cycles, should be introduced, and when. It is concluded that the optimum path for the long term begins with the prompt introduction of the low-enriched-uranium fuel cycle. For a wide range of conditions, this cycle remains the optimum throughout the very long term. Conditions of rapid nuclear growth and very high uranium price escalation rates warrant the supersedure of the low-enriched-uranium cycle by either a plutonium-topped thorium cycle or plutonium recycle, beginning between 2010 and 2025. It is also found that the uranium resource position is sound in terms of both known resources and production capability. Moreover, introduction of the low-enriched-uranium fuel cycle and 1250 MWe reactor units will assure the economic viability of nuclear power until at least 2020, even if uranium prices increase at a rate of 3.5% above inflation. The interrelationship between these two conclusions lies in the tremendous incentive for exploration which will occur if the real uranium price escalation rate is high. From a competitive viewpoint, nuclear power can withstand increases in the price of uranium. However, such increases will likely further expand the resource base, making nuclear an even more reliable energy source. (auth)

  17. Cycling across borders

    Directory of Open Access Journals (Sweden)

    Jože Kos

    1999-01-01

    Full Text Available The article describes the intent and content of the international Velo-City conference 1999, Maribor–Graz and the organisation of this cycling development planning meeting. It focuses on the resolution of the conference concerning cycling traffic policies, the emerging network of European cycling connections and the traffic planning workshop about a difficult square in Maribor. The content framework of particular papers is shown, as well as other post-conference events. In the conclusion certain useful addresses for obtaining added data on sustainable traffic planning are given.

  18. Life Cycle Sustainability Dashboard

    DEFF Research Database (Denmark)

    Traverso, Marzia; Finkbeiner, Matthias; Jørgensen, Andreas;

    2012-01-01

    One method to assess the sustainability performance of products is life cycle sustainability assessment (LCSA), which assesses product performance considering the environmental,economic, and social dimensions of the life cycle. The results of LCSA can be used to compare different products...... of sustainability is the communicability of the results by means of a graphical representation (a cartogram), characterized by a suitable chromatic scale and ranking score. The integration of LCSA and the dashboard of sustainability into a so-called Life Cycle Sustainability Dashboard (LCSD) is described here...

  19. Pain, depression and sleep disorders in patients with diabetic and nondiabetic carpal tunnel syndrome: a vicious cycle

    Directory of Open Access Journals (Sweden)

    Nermin Tanik

    2016-03-01

    Full Text Available ABSTRACT Carpal tunnel syndrome (CTS is a condition involving nerve entrapment that often leads to chronic neuropathic pain. We aimed to evaluate sleep quality and related parameters in diabetic and non-diabetic CTS patients. Method This study included a total of 366 patients with chronic CTS. These patients’ sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI and depression using the Beck Depression Inventory (BDI. The severity of neuropathic pain was evaluated using the Douleur Neuropathique-4 (DN4 questionnaire and a visual analogue scale (VAS. Results In the non-diabetic patient group, the total PSQI score was found to affect BDI and VAS, while in the diabetic patient group, the duration of symptoms affected VAS, BDI and fasting glucose levels. Conclusion For diabetic patients, hyperglycemia depression and chronification of neuropathic pain may lead to deterioration of sleep quality. Therefore, consideration of these parameters in the treatment may break a vicious cycle.

  20. Fuel cycle data survey

    International Nuclear Information System (INIS)

    A survey of the fuel cycle cost data published during 1977 and 1978 is presented in tabular and graphical form. Cost trends for the period 1965 onwards are presented for yellow cake, conversion, uranium enrichment, fuel fabrication and reprocessing

  1. Cycles in graphs

    CERN Document Server

    Alspach, BR

    1985-01-01

    This volume deals with a variety of problems involving cycles in graphs and circuits in digraphs. Leading researchers in this area present here 3 survey papers and 42 papers containing new results. There is also a collection of unsolved problems.

  2. Fuel cycle studies

    International Nuclear Information System (INIS)

    Programs are being conducted in the following areas: advanced solvent extraction techniques, accident consequences, fuel cycles for nonproliferation, pyrochemical and dry processes, waste encapsulation, radionuclide transport in geologic media, hull treatment, and analytical support for LWBR

  3. Resuscitating Real Business Cycles

    OpenAIRE

    Robert G. King; Sergio T. Rebelo

    2000-01-01

    The Real Business Cycle (RBC) research program has grown spectacularly over the last decade, as its concepts and methods have diffused into mainstream macroeconomics. Yet, there is increasing skepticism that technology shocks are a major source of business fluctuations. This chapter exposits the basic RBC model and shows that it requires large technology shocks to produce realistic business cycles. While Solow residuals are sufficiently volatile, these imply frequent technological regress. Pr...

  4. Quantifying the adaptive cycle

    Science.gov (United States)

    Angeler, David G.; Allen, Craig R.; Garmestani, Ahjond S.; Gunderson, Lance H.; Hjerne, Olle; Winder, Monika

    2015-01-01

    The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term (1994–2011) data and multivariate analysis of community structure to assess key components of the adaptive cycle. Specifically, we tested predictions about: reorganisation: spring and summer blooms comprise distinct community states; conservatism: community trajectories during individual adaptive cycles are conservative; and adaptation: phytoplankton species during blooms change in the long term. All predictions were supported by our analyses. Results suggest that traditional ecological paradigms such as phytoplankton successional models have potential for moving the adaptive cycle from a metaphor to a framework that can improve our understanding how complex systems organize and reorganize following collapse. Quantifying reorganization, conservatism and adaptation provides opportunities to cope with the intricacies and uncertainties associated with fast ecological change, driven by shifting system controls. Ultimately, combining traditional ecological paradigms with heuristics of complex system dynamics using quantitative approaches may help refine ecological theory and improve our understanding of the resilience of ecosystems.

  5. Solar Cycle Prediction

    CERN Document Server

    Petrovay, K

    2010-01-01

    A review of solar cycle prediction methods and their performance is given, including forecasts for cycle 24 and focusing on aspects of the solar cycle prediction problem that have a bearing on dynamo theory. The scope of the review is further restricted to the issue of predicting the amplitude (and optionally the epoch) of an upcoming solar maximum no later than right after the start of the given cycle. Prediction methods form three main groups. Precursor methods rely on the value of some measure of solar activity or magnetism at a specified time to predict the amplitude of the following solar maximum. Their implicit assumption is that each numbered solar cycle is a consistent unit in itself, while solar activity seems to consist of a series of much less tightly intercorrelated individual cycles. Extrapolation methods, in contrast, are based on the premise that the physical process giving rise to the sunspot number record is statistically homogeneous, i.e., the mathematical regularities underlying its variati...

  6. Helium process cycle

    Science.gov (United States)

    Ganni, Venkatarao

    2007-10-09

    A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

  7. Helium process cycle

    Science.gov (United States)

    Ganni, Venkatarao

    2008-08-12

    A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

  8. THE SURVEY OF CHILDREN WITH KASHIN-BECK DISEASE IN SICHUAN PROVINCE IN 2009%2009年四川省儿童大骨节病病情现状调查

    Institute of Scientific and Technical Information of China (English)

    李富忠; 邓佳云; 黄慧; 陈开华; 李津蜀

    2011-01-01

    [目的]了解四川省儿童大骨节病病情现状及相关危险因素.[方法]调查74个大骨节病病区村的自然环境和社会经济等基础资料,采用临床和X缦拍片的方法,调查儿童大骨节病病情现状,采集儿童发样及当地主食粮惮进行含硒量检测.[结果]临床检查7~12岁儿童4530名,检出1度患者8例,临床检出率为0.18%;拍摄7~12岁儿童右手X线片4530张,X线阳性片83张,阳性检出率平均为1.83%(0~13.73%),病情活跃程度指数平均为1.30,病情严重程度指数平均为1.83.儿童发硒水平平均为(0.26±0.07)mg/kg.粮食硒水平平均为(0.0067±0.0018)mg/kg,T2毒素含量平均为31.39 ppb(2.67~101.14).[结论]2009年四川省儿童大骨节病病情较为稳定,处于控制或基本控制范围,仅局部地区病情活跃,与主食种类及来源关系密切.%[Objective] To understand children's condition of Kaschin-Beck disease (KBD) and risk factors in Sichuan Province. [Methods] Surveyed 74 villages of Kashin-Beck disease area's natural environment and socio-economic and other basic information. Did clinical detection and shoot right hand X-ray for children, collected children's hair and staple samples to test the level of selenium in these villages. [Results] 4 530 children aged 7-12 year underwent clinical examination, 8 cases were detected as grade I patients, clinical detection rate was 0.18%; 4 530 children aged 7-12 year underwent X-ray examination, 83 X-ray films were positive. The average positive detectable rate was 1.83% (0-13.73%), index of active degree was 1.30, index of severity degree was 1.83. The average selenium level in hair of children was (0.26 ± 0.07) rag/kg. The average selenium level in staple was (0.006 7 ± 0.001 8) mg/kg, the average T2 toxin content in grain was 31.39ppb (2.67-101.14). [Conclusion] The children KBD condition is stable, which is in controlled or basically controlled state in Sichuan in 2009. Only local areas are with

  9. 西藏藏族自治区大骨节病病情调查结果分析%Analysis of a survey result on the state of Kashin-Beck disease in Tibet

    Institute of Scientific and Technical Information of China (English)

    赵生成; 白玛次旺; 扎西桑珠; 朗杰

    2011-01-01

    distribution of Kashin-Beck disease(KBD) in Tibet, and assess the disease status. Methods Between 2007 and 2008, a survey was done on KBD epidemiology which was carried out in four prefectures of 26 counties according to the east, south, west, north and center in Nakchu,Lhoca, Nyingtri and Shigatse districts of Tibet, with towns and villages as baseline survey points. According to the KBD e survey scheme, KBD clinical examination for adults was also carried out and at the same time clinical and right hand anteroposterior X-ray examinations were given to children aged 4 - 13. The partition of endemic area was based on the criteria of national standards for Kashin-Beck disease diagnoses《GB 16395-1996》. Slight KBD area:clinical prevalence of Kashin-Beck disease grade Ⅰ and above was less than 10% or X-ray detection rate < 10% of children; the moderate prevalent KBD area: clinical prevalence of Kashin-Beck disease grade Ⅰ and above was between 10% and 20% or X-ray detection rate was between 10% and 30% of children; severe KBD area: clinical prevalence of KBD grade Ⅰ and above was more than 20% or X-ray detection rate was higher than 30% of children.Results A total of 108 townships of 26 counties were surveyed, 14 686 adults were clinically examined, cases detection of grade Ⅰ and above were 637 people, the prevalence was 4.34%, and no case of grade Ⅲ was detected.Of 5769 children's right anteroposterior X-ray film, 102 were detected positive; the prevalence rate was 1.77%.Metaphysis was affected in most of the child cases, which accounting for 89.2% (91/102). Amongst all the counties, there were 10 counties, clinical detection rate of adult KBD was 0, and children's X-ray detection rate of KBD was also 0. In 1 county the clinical prevalence rate for adults KBD was 0 and X-ray detection rate for children was 3.66(7/191 ). In 12 counties the clinical prevalence rate for adults KBD was between 1.03% and 7.54%, X-ray detection rate for

  10. Inventário de Depressão de Beck (BDI e Escala de Avaliação de Depressão de Hamilton (HAM-D em pacientes com epilepsia

    Directory of Open Access Journals (Sweden)

    Guilherme Nogueira M. de Oliveira

    2011-01-01

    Full Text Available OBJETIVO: Determinar os pontos de melhor sensibilidade e especificidade do Inventário de Depressão de Beck (BDI e da Escala de Avaliação de Depressão de Hamilton (HAM-D no diagnóstico de depressão associada à epilepsia. MÉTODOS: Setenta e três pacientes de um centro de referência no tratamento da epilepsia foram submetidos à avaliação neuropsiquiátrica. Foram colhidos dados clínicos e sociodemográficos, sendo utilizados os seguintes instrumentos: entrevista clínica estruturada (MINI-PLUS para diagnóstico psiquiátrico conforme o DSM-IV, HAM-D e BDI. RESULTADOS: No momento da entrevista, 27,4% dos pacientes estavam deprimidos e 37% preenchiam critérios para diagnóstico de depressão maior ao longo da vida. A análise da curva ROC indicou que o ponto de corte em 16 (> 16 para o BDI (sensibilidade de 94,4%, especificidade de 90,6% e em 16 (> 16 para a HAM-D (sensibilidade de 95%, especificidade de 75,5% representou dicotomização ótima entre deprimidos e não deprimidos. Ambos os instrumentos apresentaram um valor preditivo negativo superior a 95%. CONCLUSÃO: A frequência de depressão maior é elevada em pacientes com epilepsia. BDI e a HAM-D podem auxiliar o clínico na identificação da depressão associada à epilepsia, diminuindo seu subdiagnóstico.

  11. Advanced heat pump cycle

    Energy Technology Data Exchange (ETDEWEB)

    Groll, E.A.; Radermacher, R.

    1993-07-01

    The desorption and absorption process of a vapor compression heat pump with a solution circuit (VCHSC) proceeds at gliding temperature intervals, which can be adjusted over a wide range. In case that the gliding temperature intervals in the desorber and the absorber overlap, a modification of the VCHSC employing a desorber/absorber heat exchange (DAHX) can be introduced, which results in an extreme reduction of the pressure ratio. Although the DAHX-cycle has features of a two-stage cycle, it still requires only one solution pump, one separator and one compressor. Such a cycle for the working pair ammonia/water is built in the Energy Laboratory of the Center for Environmental Energy Engineering at the University of Maryland. The experimental results obtained with the research plant are discussed and compared to those calculated with a simulation program. The possible temperature lift between heat source and heat sink depending on the achievable COP are presented.

  12. Superfluid thermodynamic cycle refrigerator

    Science.gov (United States)

    Swift, Gregory W.; Kotsubo, Vincent Y.

    1992-01-01

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

  13. The global sulfur cycle

    Science.gov (United States)

    Sagan, D. (Editor)

    1985-01-01

    The results of the planetary biology microbial ecology's 1984 Summer Research Program, which examined various aspects of the global sulfur cycle are summarized. Ways in which sulfur flows through the many living and chemical species that inhabit the surface of the Earth were investigated. Major topics studied include: (1) sulfur cycling and metabolism of phototropic and filamentous sulfur bacteria; (2) sulfur reduction in sediments of marine and evaporite environments; (3) recent cyanobacterial mats; (4) microanalysis of community metabolism in proximity to the photic zone in potential stromatolites; and (5) formation and activity of microbial biofilms on metal sulfides and other mineral surfaces. Relationships between the global sulfur cycle and the understanding of the early evolution of the Earth and biosphere and current processes that affect global habitability are stressed.

  14. Cycles in fossil diversity

    Energy Technology Data Exchange (ETDEWEB)

    Rohde, Robert A.; Muller, Richard A.

    2004-10-20

    It is well-known that the diversity of life appears to fluctuate during the course the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0-542 Ma). Using Sepkoski's compendium of the first and last stratigraphic appearances of 36380 marine genera, we report a strong 62 {+-} 3 Myr cycle, which is particularly strong in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski may be an aspect of this cycle. Because of the high statistical significance, we also consider contributing environmental factors and possible causes.

  15. Revenue cycle management.

    Science.gov (United States)

    Manley, Ray; Satiani, Bhagwan

    2009-11-01

    With the widening gap between overhead expenses and reimbursement, management of the revenue cycle is a critical part of a successful vascular surgery practice. It is important to review the data on all the components of the revenue cycle: payer contracting, appointment scheduling, preregistration, registration process, coding and capturing charges, proper billing of patients and insurers, follow-up of accounts receivable, and finally using appropriate benchmarking. The industry benchmarks used should be those of peers in identical groups. Warning signs of poor performance are discussed enabling the practice to formulate a performance improvement plan.

  16. Global water cycle

    Science.gov (United States)

    Robertson, Franklin; Goodman, Steven J.; Christy, John R.; Fitzjarrald, Daniel E.; Chou, Shi-Hung; Crosson, William; Wang, Shouping; Ramirez, Jorge

    1993-01-01

    This research is the MSFC component of a joint MSFC/Pennsylvania State University Eos Interdisciplinary Investigation on the global water cycle extension across the earth sciences. The primary long-term objective of this investigation is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates change on both global and regional scales. Significant accomplishments in the past year are presented and include the following: (1) water vapor variability; (2) multi-phase water analysis; (3) global modeling; and (4) optimal precipitation and stream flow analysis and hydrologic processes.

  17. Marine nitrogen cycle

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.

    and particulate organic forms, respectively) and atmospheric deposition (~50 Tg N a -1 ), a substantial fraction of which is believed to be of anthropogenic (human-made) origin. Of the various loss terms of combined nitrogen from the ocean, emission of N 2 O... and nitrous oxide budgets: Moving targets as we enter the anthropocene?, Sci. Mar., 65, 85-105, 2001. Page 2 of 3Marine nitrogen cycle - Encyclopedia of Earth 11/20/2006http://www.eoearth.org/article/Marine_nitrogen_cycle square6 Gruber, N.: The dynamics...

  18. Carbon cycle makeover

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Kump, Lee R.

    2013-01-01

    remaining in sediments after respiration leave a residual of oxygen in the atmosphere. The source of oxygen to the atmosphere represented by organic matter burial is balanced by oxygen sinks associated with rock weathering and chemical reaction with volcanic gases. This is the long-term carbon and oxygen...... geochemical cycle. But Earth is an old planet, and oxygen levels have changed through time (2). On page 540 of this issue, Schrag et al. (3) challenge the most commonly used geochemical approach to assess long-term changes in the coupled oxygen and carbon cycles....

  19. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik;

    1999-01-01

    To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....

  20. The Science of Cycling

    Science.gov (United States)

    Crompton, Zoe; Daniels, Shelley

    2014-01-01

    Children are engaged by finding out about science in the real world (Harlen, 2010). Many children will be cyclists or will have seen or heard about the success of British cyclists in the Olympics and the Tour de France. This makes cycling a good hook to draw children into learning science. It is also a good cross-curricular topic, with strong…

  1. Assisted Cycling Tours

    Science.gov (United States)

    Hollingsworth, Jan Carter

    2008-01-01

    This article discusses Assisted Cycling Tours (ACT), a Westminster, Colorado based 501(c)3, non-profit that is offering the joy of bicycle tours in breathtaking, scenic locations to children and adults with developmental and physical disabilities and their families. ACT was founded by Bob Matter and his son David with a goal of opening up the…

  2. Re-Cycling

    Science.gov (United States)

    Brown, Robert W.; Covault, Corbin E.

    2015-01-01

    An old comedy routine on Saturday Night Live by Father Guido Sarducci introduced a "Five-Minute University," because five minutes is all that's remembered after graduation anyway. In counterpoint, we discuss "cycling," a teaching method for memory enhancement. Our principal implementation consists of offering a simple version…

  3. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    Strong institutional constraints and better-informed voters may lead re-election seeking incumbents to shift the use of political business cycle mechanisms away from monetary and fiscal policy towards other policy domains that are more easily manipulable, targetable, and timeable. We investigate...

  4. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    2009-01-01

    Strong institutional constraints and better-informed voters may lead re-election seeking incumbents to shift the use of political business cycle mechanisms away from monetary and fiscal policy towards other policy domains that are more easily manipulable, targetable, and timeable. We investigate...

  5. Boundedly rational credit cycles

    OpenAIRE

    S??ez, Mar??a

    1996-01-01

    We propose an evolutionary model of a credit market. We show that the economy exhibits credit cycles. The model predicts dynamics which are consistent with some evidence about the Great Depression. Real shocks trigger episodes of credit--crunch which are observed in the process of adjustment towards the post shock equilibrium.

  6. Life Cycle Collection Management

    Directory of Open Access Journals (Sweden)

    Helen Shenton

    2003-09-01

    Full Text Available Life cycle collection management is a way of taking a long-term approach to the responsible stewardship of the British Library's collections and is one of the Library's strategic strands. It defines the different stages in a collection item's existence over time. These stages range from selection and acquisitions processing, cataloguing and press marking, through to preventive conservation, storage and retrieval. Life cycle collection management seeks to identify the costs of each stage in order to show the economic interdependencies between the phases over time. It thereby aims to demonstrate the long-term consequences of what the library takes into its collections, by making explicit the financial and other implications of decisions made at the beginning of the life cycle for the next 100 plus years. This paper describes the work over the past year at the British Library on this complex and complicated subject. It presents the emerging findings and suggests how it can be used for practical reasons (by individual curators and selectors and for economic, governance and political purposes. The paper describes the next steps in the project, for example, on a predictive data model. The British Library is seeking to benchmark itself against comparable organisations in this area. It intends to work with others on specific comparison for example, of life cycle costing of electronic and paper journals, as a prelude to eliding digital and 'traditional' formats.

  7. Skills, sunspots and cycles

    DEFF Research Database (Denmark)

    Busato, Francesco; Marchetti, Enrico

    This paper explores the ability of a class of one-sector,multi-input models to generate indeterminate equilibrium paths, andendogenous cycles, without relying on factors' hoarding. The modelpresents a novel theoretical economic mechanism that supportssunspot-driven expansions without requiring up...

  8. The Pneumocystis life cycle

    Directory of Open Access Journals (Sweden)

    Cécile-Marie Aliouat-Denis

    2009-05-01

    Full Text Available First recognised as "schizonts" of Trypanosoma cruzi, Pneumocystis organisms are now considered as part of an early-diverging lineage of Ascomycetes. As no robust long-term culture model is available, most data on the Pneumocystis cell cycle have stemmed from ultrastructural images of infected mammalian lungs. Although most fungi developing in animals do not complete a sexual cycle in vivo, Pneumocystis species constitute one of a few exceptions. Recently, the molecular identification of several key players in the fungal mating pathway has provided further evidence for the existence of conjugation and meiosis in Pneumocystisorganisms. Dynamic follow-up of stage-to-stage transition as well as studies of stage-specific proteins and/or genes would provide a better understanding of the still hypothetical Pneumocystislife cycle. Although difficult to achieve, stage purification seems a reasonable way forward in the absence of efficient culture systems. This mini-review provides a comprehensive overview of the historical milestones leading to the current knowledge available on the Pneumocystis life cycle.

  9. Stellar magnetic cycles

    Science.gov (United States)

    Baliunas, S. L.

    2004-05-01

    Is hope for understanding the solar magnetic cycle to be found in stars? Observations of stars with significant sub-surface convective zones -- masses smaller than about 1.5 solar masses on the lower main sequence and many types of cool, post-main-sequence stars -- indicate the presence of surface and atmospheric inhomogeneities analogous to solar magnetic features, making stellar magnetic activity a cosmically widespread phenomenon. Observations have been made primarily in visible wavelengths, and important information has also been derived from the ultraviolet and x-ray spectrum regions. Interannual to interdecadal variability of spectrum indicators of stellar magnetic features is common, and in some cases similar in appearance to the 11-year sunspot cycle. Successful models of the physical processes responsible for stellar magnetic cycles, typically cast as a magnetohydrodynamic dynamo, require advances in understanding not only convection but also the magnetic field's interaction with it. The observed facts that underpin the hope for models will be summarized. Properties of stellar magnetic cycles will be compared and contrasted with those of the sun, including inferences from paleo-environmental reservoirs that contain information on solar century- to millennial-scale magnetic variability. Partial support of this research came from NASA NAG5-7635, NRC COBASE, CRDF 322, MIT-MSG 5710001241, JPL 1236821, AF 49620-02-1-0194, Richard Lounsberry Foundation, Langley-Abbot, Rollins, Scholarly Studies and James Arthur Funds (Smithsonian Institution) and several generous individuals.

  10. Big Data and Cycling

    NARCIS (Netherlands)

    Romanillos, Gustavo; Zaltz Austwick, Martin; Ettema, Dick; De Kruijf, Joost

    2016-01-01

    Big Data has begun to create significant impacts in urban and transport planning. This paper covers the explosion in data-driven research on cycling, most of which has occurred in the last ten years. We review the techniques, objectives and findings of a growing number of studies we have classified

  11. The Geologic Nitrogen Cycle

    Science.gov (United States)

    Johnson, B. W.; Goldblatt, C.

    2013-12-01

    N2 is the dominant gas in Earth's atmosphere, and has been so through the majority of the planet's history. Originally thought to only be cycled in significant amounts through the biosphere, it is becoming increasingly clear that a large degree of geologic cycling can occur as well. N is present in crustal rocks at 10s to 100s of ppm and in the mantle at 1s to perhaps 10s of ppm. In light of new data, we present an Earth-system perspective of the modern N cycle, an updated N budget for the silicate Earth, and venture to explain the evolution of the N cycle over time. In an fashion similar to C, N has a fast, biologically mediated cycle and a slower cycle driven by plate tectonics. Bacteria fix N2 from the atmosphere into bioavailable forms. N is then cycled through the food chain, either by direct consumption of N-fixing bacteria, as NH4+ (the primary waste form), or NO3- (the most common inorganic species in the modern ocean). Some organic material settles as sediment on the ocean floor. In anoxic sediments, NH4+ dominates; due to similar ionic radii, it can readily substitute for K+ in mineral lattices, both in sedimentary rocks and in oceanic lithosphere. Once it enters a subduction zone, N may either be volatilized and returned to the atmosphere at arc volcanoes as N2 or N2O, sequestered into intrusive igneous rocks (as NH4+?), or subducted deep into the mantle, likely as NH4+. Mounting evidence indicates that a significant amount of N may be sequestered into the solid Earth, where it may remain for long periods (100s m.y.) before being returned to the atmosphere/biosphere by volcanism or weathering. The magnitude fluxes into the solid Earth and size of geologic N reservoirs are poorly constrained. The size of the N reservoirs contained in the solid Earth directly affects the evolution of Earth's atmosphere. It is possible that N now sequestered in the solid Earth was once in the atmosphere, which would have resulted in a higher atmospheric pressure, and

  12. Stirling cycle cryogenic cooler

    Science.gov (United States)

    Gasser, M. G.; Sherman, A.; Studer, P. A.; Daniels, A.; Goldowsky, M. P. (Inventor)

    1983-01-01

    A long lifetime Stirling cycle cryogenic cooler particularly adapted for space applications is described. It consists of a compressor section centrally aligned end to end with an expansion section, and respectively includes a reciprocating compressor piston and displacer radially suspended in interconnecting cylindrical housings by active magnetic bearings and has adjacent reduced clearance regions so as to be in noncontacting relationship therewith and wherein one or more of these regions operate as clearance seals. The piston and displacer are reciprocated in their housings by linear drive motors to vary the volume of respectively adjacent compression and expansion spaces which contain a gaseous working fluid and a thermal regenerator to effect Stirling cycle cryogenic cooling.

  13. Stirling cycle cryogenic cooler

    Science.gov (United States)

    Gasser, M. G.; Sherman, A.; Studer, P. A.; Daniels, A.; Goldowsky, M. P.

    1983-06-01

    A long lifetime Stirling cycle cryogenic cooler particularly adapted for space applications is described. It consists of a compressor section centrally aligned end to end with an expansion section, and respectively includes a reciprocating compressor piston and displacer radially suspended in interconnecting cylindrical housings by active magnetic bearings and has adjacent reduced clearance regions so as to be in noncontacting relationship therewith and wherein one or more of these regions operate as clearance seals. The piston and displacer are reciprocated in their housings by linear drive motors to vary the volume of respectively adjacent compression and expansion spaces which contain a gaseous working fluid and a thermal regenerator to effect Stirling cycle cryogenic cooling.

  14. Gap Cycling for SWIFT

    CERN Document Server

    Corum, Curtis A; Snyder, Carl J; Garwood, Michael

    2013-01-01

    Purpose: SWIFT (SWeep Imaging with Fourier Transformation) is a non- Cartesian MRI method with unique features and capabilities. In SWIFT, radiofrequency (RF) excitation and reception are performed nearly simultaneously, by rapidly switching between transmit and receive during a frequency-swept RF pulse. Because both the transmitted pulse and data acquisition are simultaneously amplitude-modulated in SWIFT (in contrast to continuous RF excitation and uninterrupted data acquisition in more familiar MRI sequences), crosstalk between different frequency bands occurs in the data. This crosstalk leads to a "bulls-eye" artifact in SWIFT images. We present a method to cancel this inter-band crosstalk by cycling the pulse and receive gap positions relative to the un-gapped pulse shape. We call this strategy "gap cycling." Methods: We carry out theoretical analysis, simulation and experiments to characterize the signal chain, resulting artifacts, and their elimination for SWIFT. Results: Theoretical analysis reveals t...

  15. Archaea in biogeochemical cycles.

    Science.gov (United States)

    Offre, Pierre; Spang, Anja; Schleper, Christa

    2013-01-01

    Archaea constitute a considerable fraction of the microbial biomass on Earth. Like Bacteria they have evolved a variety of energy metabolisms using organic and/or inorganic electron donors and acceptors, and many of them are able to fix carbon from inorganic sources. Archaea thus play crucial roles in the Earth's global geochemical cycles and influence greenhouse gas emissions. Methanogenesis and anaerobic methane oxidation are important steps in the carbon cycle; both are performed exclusively by anaerobic archaea. Oxidation of ammonia to nitrite is performed by Thaumarchaeota. They represent the only archaeal group that resides in large numbers in the global aerobic terrestrial and marine environments on Earth. Sulfur-dependent archaea are confined mostly to hot environments, but metal leaching by acidophiles and reduction of sulfate by anaerobic, nonthermophilic methane oxidizers have a potential impact on the environment. The metabolisms of a large number of archaea, in particular those dominating the subsurface, remain to be explored.

  16. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik;

    1999-01-01

    OUTCOME MEASURE(S): The probability of pregnancy occurring within one menstrual cycle (fecundity). RESULT(S): In women who had a cycle length that differed by >10 days from the usual cycle length, fecundity was approximately 25% that of women who had no variation (odds ratio 0.25, 95% confidence interval...... 0.09-0.68). When the combined effect of cycle variation and cycle length was assessed, cycle variation was a persistent strong predictor of fecundity. CONCLUSION(S): The mechanisms of the present findings probably are female functional disturbances in ovulation, conception, implantation......, or sustained pregnancy, linked with variable menstrual cycle length. Thus, identification of medical and environmental causes of abnormal menstrual cycle patterns may provide clues to the causes of infertility. Moreover, the menstrual cycle pattern also should be taken into consideration in the clinical...

  17. Assessing Cycling Participation in Australia

    Directory of Open Access Journals (Sweden)

    Chris Rissel

    2013-01-01

    Full Text Available Planning and evaluating cycling programs at a national or state level requires accurate measures of cycling participation. However, recent reports of cycling participation have produced very different estimates. This paper examines the reported rates of cycling in five recent population surveys of cycling. Three surveys (one national and two from Sydney asking respondents when they last rode a bicycle generated cycling participation (cycled in the past year estimates of 29.7%, 34.1% and 28.9%. Two other national surveys which asked participants to recall (unprompted any physical activity done for exercise, recreation or sport in the previous 12 months, estimated cycling in the past year as 11.1% and 6.5%. While unprompted recall of cycling as a type of physical activity generates lower estimates of cycling participation than specific recall questions, both assessment approaches produced similar patterns of cycling by age and sex with both approaches indicating fewer women and older adults cycling. The different question styles most likely explain the substantial discrepancies between the estimates of cycling participation. Some differences are to be expected due to sampling variability, question differences, and regional variation in cycling.

  18. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    The papers presented at the International Conference on The Nuclear Fuel Cycle, held at Stockholm, 28 to 31 October 1975, are reviewed. The meeting, organised by the U.S. Atomic Industrial Forum, and the Swedish Nuclear Forum, was concerned more particularly with economic, political, social and commercial aspects than with tecnology. The papers discussed were considered under the subject heading of current status, uranium resources, enrichment, and reprocessing. (U.K.)

  19. Concordance in Business Cycles

    OpenAIRE

    C. John McDermott; Alasdair Scott

    2000-01-01

    We study the properties of a test that determines whether two time series comove. The test computes a simple nonparametric statistic for “concordance,” which describes the proportion of time that the cycles of two series spend in the same phase. We establish the size and power properties of this test. As an illustration, the procedures are applied to output series from selected major industrial countries. We find limited evidence of widespread concordance for these countries.

  20. Cycles in Nonlinear Macroeconomics

    OpenAIRE

    Voronin, Anatoly V.; Chernyshov, Sergey I.

    2007-01-01

    The monograph is concerned with some key problems of the theory of nonlinear economic dynamics. The authors' concept consists in analyzing the problem of structural instability of economic systems within the framework of the synergetic paradigm. As examples, the classical models of macroeconomics are considered. The authors present the results of the study of the phenomenon of self-organization in open and nonequilibrium economic systems. The generation of limit cycles, as well as of more com...

  1. Steps and cycles

    OpenAIRE

    Chadwick, Andy

    2015-01-01

    Andy Chadwick* explains how interaction between continuous trend with natural climate cycles produces the observed stepped pattern of global warming Climate-change ‘sceptics’ have made great mileage out of the current hiatus in observed global warming. Atmospheric temperatures have not really increased since the turn of the 21st Century, a fact frequently cited as incompatible with, or even disproving, global warming. These same commentators draw a discreet veil over the fact that temper...

  2. FUZZY REASONING IN CYCLES

    Institute of Scientific and Technical Information of China (English)

    曹立明

    1990-01-01

    By the similarity between the syllogism in logic and a path proposition in graph theory,a new concept,fuzzy reasoning graph G has been given in this paper. Transitive closure has been studied and used to do reasoning related to self-loop in G,and an algorithm has been designed to cope with reasoning in other cycles in G. Both approaches are applicable and efficient.

  3. Nuclear Fuel Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Deborah J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-28

    These slides will be presented at the training course “International Training Course on Implementing State Systems of Accounting for and Control (SSAC) of Nuclear Material for States with Small Quantity Protocols (SQP),” on November 3-7, 2014 in Santa Fe, New Mexico. The slides provide a basic overview of the Nuclear Fuel Cycle. This is a joint training course provided by NNSA and IAEA.

  4. International Business Cycle

    Directory of Open Access Journals (Sweden)

    Marek Lubiński

    2007-06-01

    Full Text Available Prime stylized facts of international business cycle theory refer to positive correlation in the cyclical components of important macroeconomic variables across countries. However a number of indicators of business cycle synchronization do not point to clear trends. It can be ascribed to the fact that different forces influence level of business cycle correlation. When investigating into the forces behind the commonness in aggregate fluctuations economic research seems to have pointed in two directions. One strand of the literature examines the idea of common exogenous shocks that affect economies simultaneously. In addition to that economic interdependencies such as trade in goods and services or capital account transactions may serve as the channels through which disturbances spill over across countries.The observed degree of output co movement reflects both the nature of the shocks that have occurred and the degree of economic interdependence. In the periods when common shocks prevail level of synchronization is usually higher than in times of transmission dominance.

  5. X-ray observation on knee joint space of adults' Kaschin-Beck disease%成人大骨节病膝关节间隙的X线观察

    Institute of Scientific and Technical Information of China (English)

    刘辉; 李德安; 邓晴; 高本; 刘宁

    2009-01-01

    Objective To observe and scale knee joint space of the patients who suffered adults' Kaschin-Beck disease (KBD) in Shangzhi City of Heilongjiang Province in order to acquire basic knowledge for upcoming intervention trial. Methods Clinical test was proceeded in adults aged above 40 in Guanghui Village of Shangzhi City in 2007. In typical patients, bilateral knee X-ray was taken and knee joint space was scaled. Three points were chosen on inner and outer epicondyle of each knee and results were recorded. Results There were 307 peoples over the age of 40 in the village. Two hundred eighty-two accepted clinical test, in a rate of 91.9%. Eighty out of 282 suffered KBD, accounting for 28.4%. When the patients' condition became more serious, measurements from flank, middle, inside points on outer epicondyle of joint space presented a narrowing trend [degree Ⅰ: (5.85±0.17), (4.84±0.17), (4.36±0.18)mm; degree Ⅱ: (5.11±0.43), (4.24±0.34), (3.48±0.28)nun; degree Ⅲ: (3.59± 0.78), (3.10±0.56), (2.14±0.62)mm; Fflank,middle,inside= 6.547,5.372,10.302, all P 0.05]. Joint space 0.05].关节间隙<5.00 mm的测量点共618个,内上髁关节面测量点(363个)明显多于外上髁关节面(255个),二者比较差异有统计学意义(χ2=9.59,P<0.05).结论 光辉村成年大骨节病病例较多;伴随病情加重患者膝关节间隙呈变窄趋势,尤以外上髁表现明显;但患者以内上髁狭窄病变为多见.

  6. Trial and Evaluation of Beck Depression Inventory for Teachers in Disaster Area%Beck抑郁问卷在灾区教师中的试用及评价

    Institute of Scientific and Technical Information of China (English)

    游永恒; 于少萍; 梁斌

    2011-01-01

    To evaluate the psychometric properties of the Beck depression inventory (BDI), and use BDI for determination of the 750 disaster area teachers and to analyze the reliability and validity of BDI.Results show that all items tested on the degree of depression show good discernment, scale Cronbach's α coefficient is 0.915, Spearman-Brown split-half reliability coefficient is 0.864.Factor analysis indicates that somatic disorder and depression are two major factors.This is consistent with the definition of depression.Butthe difference of load between above two factors in sin(E), self - blame( H), crying(J), weight loss(S) is less than 0.2, which shows the poor construction validity.Depression scores and overall well-being in all dimensions and total score show significantly negative correlation (r= -0.416 ~ -0.577,P <0.001 ), which indicates that the BDI scale has good criterion vahdity; BDI Chinese translation is generally stable, but the construction validity is unsatisfactory and the attention should be paid in applications.%为评价Beck抑郁问卷(BDI)的心理测量特性.使用BDI测定了750名灾区教师,分析BDI的信度和效度.结果表明所有题项对被试的抑郁程度均有良好的鉴别力,量表的Cronbach's a系数为0.915,Spearman-Brown分半信度系数为0.864.因子分析后共得到躯体障碍和抑郁情绪两大因子,与心理学中对抑郁的定义较为一致.但罪感(E)、自责(H)、痛哭(J)、体重减轻(S)等4个条目在两个因子上的载荷差值均小于0.2,表明量表的结构效度欠佳.抑郁总分与总体幸福感各个维度及总分均存在显著的负相关(r=-0.416~-0.577,P<0.001),表明BDI量表具有较好的校标效度;BDI中译本总体稳定,但结构效度欠理想,在使用中应引起注意.

  7. Extremely low sulfate availability — a new explaination of pathopoiesis of Kaschin-Beck Disease%极其低下的硫酸根可利用度—大骨节病病因新解

    Institute of Scientific and Technical Information of China (English)

    关放; 王治伦; 陈静宏

    2013-01-01

    Kaschin - Beck disease ( KBD) is an endemic and degenerative osteoarthropathic disease. Currently the etiology of the disease is unclear. This article reviews the effects of extremely low sulphate availability in the diets of residents in the regions of high occurrence of the disease. KBD is associated with an abnormal metabolism of proteoglycans in the articular and epiphyseal plate cartilages and behaves as undersulfation and enhanced catabolism similar to osteoarthritis. Low sulfate levels can decrease the incorporation of sulfate into proteoglycans synthesized by chondrocytes and can enhance the catabolism of the proteoglycans. The extremely low sulphate availability pathopoiesis hypothesis can reasonably explain the main epidemiological phenomena of KBD, i. e. , a severe Se deficiency resulting in the impairment of methionine transsulfuration. Mouldy foods and drinking water with abundant phenol acid compounds further decrease the originally low sulphate availability in KBD patients and promote the occurrence of KBD.%大骨节病是一种地方性、畸形性骨关节病,至今病因不明.本文论述了大骨节病饮食中过低的硫酸根可利用度在大骨节病发生中的作用.大骨节病表现出蛋白聚糖低硫酸化和增强的分解代谢特征,而低硫酸根培养液能降低软骨细胞合成的糖胺聚糖中硫酸根的掺入量,同时体外实验表明过低的硫酸根可利用度可增强软骨蛋白聚糖的分解代谢.大骨节病过低的硫酸根可利用度病因说能够较合理地解释主要的大骨节病流行病学现象,如严重的硒缺乏导致蛋氨酸转硫作用的损害,霉变的粮食和富含酚酸类化合物的饮水进一步降低了大骨节病区人群本来就很低下的硫酸根可利用度,导致了大骨节病的发生.

  8. Terrestrial Carbon Cycle Variability

    Science.gov (United States)

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2, temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1), and

  9. Bifurcation of limit cycles near equivariant compound cycles

    Institute of Scientific and Technical Information of China (English)

    Mao-an HAN; Tong-hua ZHANG; Hong ZANG

    2007-01-01

    In this paper we study some equivariant systems on the plane. We first give some criteria for the outer or inner stability of compound cycles of these systems. Then we investigate the number of limit cycles which appear near a compound cycle of a Hamiltonian equivariant system under equivariant perturbations. In the last part of the paper we present an application of our general theory to show that a Z3 equivariant system can have 13 limit cycles.

  10. Cycle-to-cycle variability as an optimal behavioral strategy

    OpenAIRE

    Brezina, Vladimir; Proekt, Alex; Weiss, Klaudiusz R.

    2006-01-01

    Aplysia feeding behavior is highly variable from cycle to cycle. In some cycles, when the variability causes a mismatch between the animal's movements and the requirements of the feeding task, the variability makes the behavior unsuccessful. We propose that the behavior is variable nevertheless because the variability serves a higher-order functional purpose. When the animal is faced with a new and only imperfectly known feeding task in each cycle, the variability implements a trial-and-error...

  11. How well can business cycle accounting account for business cycles?

    OpenAIRE

    Otsu, Keisuke

    2012-01-01

    The business cycle accounting method introduced by Chari, Kehoe and McGrattan (2007) is a useful tool to decompose business cycle fluctuations into their contributing factors. However, the model estimated by the maximum likelihood method cannot replicate business cycle moments computed from data. Moment-based estimation might be an attractive alternative if the purpose of the research is to study business cycle properties such as volatility, persistence and cross-correlation of variables inst...

  12. 2012年山东省大骨节病病情调查结果分析%Analysis of investigating results of Kashin-Beck disease in Shandong Province in 2012

    Institute of Scientific and Technical Information of China (English)

    云中杰; 李伟国; 尹玉岩; 高杰; 潘恩群; 王波; 边建朝; 陈培忠

    2014-01-01

    目的:了解山东省大骨节病的病情和防控措施落实现状,为消除大骨节病考核验收工作提供科学依据。方法按照国家《2012年医改地方病防治项目实施方案》和《2012年山东省医改大骨节病防治项目技术实施方案》的要求,在青州市的4个病区乡镇中,每个乡镇抽取3个病区村作为调查点,了解大骨节病防控措施落实情况,包括调查点的人口、耕种、主食以及防控措施落实等情况。对每个调查村的全部7~12岁儿童进行临床和X线摄片检查,人数少于50人时,在调查村附近再增加1个病区村,并检查该村的全部7~12岁儿童。分别计算临床Ⅰ度、Ⅱ度、Ⅲ度检出例数及检出率;X线阳性检出率;干骺、骨骺、骨端、腕骨、三联征检出例数及检出率。临床和X线诊断依据《大骨节病诊断标准》(WS/T 207-2010)。结果共调查了14个病区村。近3年病区未实施补硒措施,也未实行搬迁和异地育人;病区农作物以小麦和玉米为主,居民主食以面粉为主,占80%以上,且购食外地粮仅占11%;退耕还林(草)面积占原有耕地的0.32%(36/11151);改种经济作物面积占原有耕地的1.17%(131/11151)。临床和X线摄片检查7~12岁儿童共536名,临床检查未检出大骨节病患儿;X线摄片检查,检出阳性患儿6例,均为单纯干骺端改变,平均X线检出率为1.12%(6/536),未检出骨骺、骨端及腕骨阳性患儿。结论山东省大骨节病病情得到了有效控制,但由于大骨节病病因未明,仍需建立可持续控制大骨节病的长效机制,进一步完善监测体系,做好病情动态监测工作。%Objective To understand the status quo of the illness situation and the implementation of prevention and control measures on Kashin-Beck disease( KBD ) in Shandong Province , and provide a scientific basis for assessment and acceptance of the work

  13. The software life cycle

    CERN Document Server

    Ince, Darrel

    1990-01-01

    The Software Life Cycle deals with the software lifecycle, that is, what exactly happens when software is developed. Topics covered include aspects of software engineering, structured techniques of software development, and software project management. The use of mathematics to design and develop computer systems is also discussed. This book is comprised of 20 chapters divided into four sections and begins with an overview of software engineering and software development, paying particular attention to the birth of software engineering and the introduction of formal methods of software develop

  14. Geomicrobiological cycling of antimony

    Science.gov (United States)

    Kulp, T. R.; Terry, L.; Dovick, M. A.; Braiotta, F.

    2013-12-01

    Microbiologically catalyzed oxidation and reduction of toxic metalloids (e.g., As, Se, and Te) generally proceeds much faster than corresponding abiotic reactions. These microbial transformations constitute biogeochemical cycles that control chemical speciation and environmental behavior of metalloids in aqueous environments. Particular progress has been made over the past two decades in documenting microbiological biotransformations of As, which include anaerobic respiratory reduction of As(V) to As(III), oxidation of As(III) to As(V) linked to chemoautotrophy or photoautotrophy, and cellular detoxification pathways. By contrast, microbial interactions with Sb, As's group 15 neighbor and a toxic element of emerging global concern, are poorly understood. Our work with sediment microcosms, enrichment cultures, and bacterial isolates suggests that prokaryotic metabolisms may be similarly important to environmental Sb cycling. Enrichment cultures and isolates from a Sb-contaminated mine site in Idaho exhibited Sb(V)-dependent heterotrophic respiration under anaerobic conditions and Sb(III)-dependent autotrophic growth in the presence of air. Live, anoxic cultures reduced 2 mM Sb(V) to Sb(III) within 5 d, while no activity occurred in killed controls. Sb(V) reduction was stimulated by lactate or acetate and was quantitatively coupled to the oxidation of lactate. The oxidation of radiolabeled 14C-acetate (monitored by GC-GPC) demonstrated Sb(V)-dependent oxidation to 14CO2, suggesting a dissimilatory process. Sb(V) dependent growth in cultures was demonstrated by direct counting. Microbiological reduction of Sb(V) also occurred in anerobic sediment microcosms from an uncontaminated suburban lake, but did not appear to be linked to growth and is interpreted as a mechanism of biological detoxification. Aerobic microcosms and cultures from the Idaho mine oxidized 2 mM Sb(III) to Sb(V) within 7 d and coupled this reaction to cell growth quantified by direct counting. An

  15. Revenue cycle management: part I.

    Science.gov (United States)

    Crew, Matt

    2006-01-01

    The revenue cycle starts long before a patient is seen and continues until a claim is completely resolved. Each step in the revenue cycle must be clearly defined and easy to follow. Use of various tools such as templates, forms, reports, spreadsheets, and components of your practice management system will help to provide the consistency you need for profitable revenue cycle management.

  16. Sometimes "Newton's Method" Always "Cycles"

    Science.gov (United States)

    Latulippe, Joe; Switkes, Jennifer

    2012-01-01

    Are there functions for which Newton's method cycles for all non-trivial initial guesses? We construct and solve a differential equation whose solution is a real-valued function that two-cycles under Newton iteration. Higher-order cycles of Newton's method iterates are explored in the complex plane using complex powers of "x." We find a class of…

  17. Paths and cycles of hypergraphs

    Institute of Scientific and Technical Information of China (English)

    王建方; Tony; T.Lee

    1999-01-01

    Hypergraphs are the most general structures in discrete mathematics. Acyclic hypergraphs have been proved very useful in relational databases. New systems of axioms for paths, connectivity and cycles of hypergraphs are constructed. The systems suit the structure properties of relational databases. The concepts of pseudo cycles and essential cycles of hypergraphs are introduced. They are relative to each other. Whether a family of cycles of a hypergraph is dependent or independent is defined. An enumeration formula for the maximum number of independent essential cycles of a hypergraph is given.

  18. Part 5. Fuel cycle options

    International Nuclear Information System (INIS)

    The results of the FBR fuel cycle study that supported US contributions to the INFCE are presented. Fuel cycle technology is reviewed from both generic and historical standpoints. Technology requirements are developed within the framework of three deployment scenarios: the reference international, the secured area, and the integral cycle. Reprocessing, fabrication, waste handling, transportation, and safeguards are discussed for each deployment scenario. Fuel cycle modifications designed to increase proliferation defenses are described and assessed for effectiveness and technology feasibility. The present status of fuel cycle technology is reviewed and key issues that require resolution are identified

  19. 大骨节病健康相关生存质量架构的质性研究%Framework for assessing health related quality of life of Kaschin-Beck disease: a qualitative research

    Institute of Scientific and Technical Information of China (English)

    方华; 郭雄; 夏传涛; 刘明; 任峰玲; 董睿

    2012-01-01

    目的 建立我国大骨节病健康相关生存质量的架构,以期反映出大骨节病对患者生存质量的影响.方法 运用质性描述性研究,采用世界卫生组织(WHO)对健康及生存质量的定义发展半开放式问题,通过焦点团体访谈和面对面访谈,收集陕西省大骨节病患病率较高的病区麟游县、永寿县29名大骨节病专家和48名大骨节病患者的意见,并用WHO生存质量问卷(WHOQOL-100)的架构作为模板,用内容模板法分析访谈资料.结果 大骨节病健康相关生存质量架构包含了4个领域:身体活动能力、家庭/社会支持、经济、心理状态;反映在11个方面:疼痛与不适,身体功能与活动限制、饮食与睡眠、社会关系、对家庭责任的担忧、社会支持、经济状况、住房及周围环境、对外貌的担心、精神状况、总的健康状况;共有69个条目.结论 建立了大骨节病健康相关生存质量的架构,该架构凸显了大骨节病对患者生存质量的影响,特异性较强.%Objective To identify the framework for assessing health related quality of life(HRQOL) of Kaschin-Beck disease(KBD),in order to reflect the impact of KBD on quality of life in patients with the disease.Methods Qualitative descriptive research was adopted.Semi-open ended questions were developed by using the World Health Organization(WHO) definitions of health and quality of life.Group interview and face to face interviews were conducted on 48 patients with KBD and 29 health care experts on KBD in Linyou and Yongshou counties,Shaanxi province,which were higher prevalence areas of KBD.Content template analysis was conducted and the template was based on the WHOQOL-100's framework.Results The framework of HRQOL for KBD included four domains:physical activity,familial/social support,economic and psychological state.There were also eleven facets which were:pain and discomfort,physical function and activity limitation,diet and sleeping

  20. Krebs Cycle Wordsearch

    Science.gov (United States)

    Helser, Terry L.

    2001-04-01

    This puzzle embeds 46 names, terms, abbreviations, and acronyms about the citric acid (Krebs) cycle in a 14- x 17-letter matrix. A descriptive narrative beside it describes important features of the pathway. All the terms a student needs to find are embedded there with the first letter followed by underlined blanks to be completed. Therefore, the students usually must find the terms to know how to spell them, correctly fill in the blanks in the narrative with the terms, and then find and highlight the terms in the letter matrix. When all are found, the 24 unused letters complete a sentence that describes a major feature of this central pathway. The puzzle may be used as homework, an extra-credit project, or a group project in the classroom in any course where basic metabolism is learned. It disguises as fun the hard work needed to learn the names of the intermediates, enzymes, and cofactors.

  1. Open cycle thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Robert Stowers

    2000-01-01

    A new type of thermodynamic device combining a thermodynamic cycle with the externally applied steady flow of an open thermodynamic process is discussed and experimentally demonstrated. The gas flowing through this device can be heated or cooled in a series of semi-open cyclic steps. The combination of open and cyclic flows makes possible the elimination of some or all of the heat exchangers (with their associated irreversibility). Heat is directly exchanged with the process fluid as it flows through the device when operating as a refrigerator, producing a staging effect that tends to increase First Law thermodynamic efficiency. An open-flow thermoacoustic refrigerator was built to demonstrate this concept. Several approaches are presented that describe the physical characteristics of this device. Tests have been conducted on this refrigerator with good agreement with a proposed theory.

  2. HTGR fuel cycle

    International Nuclear Information System (INIS)

    In the spring of 1987, the HTGR fuel cycle project has been existing for ten years, and for this reason a status seminar has been held on May 12, 1987 in the Juelich Nuclear Research Center, that gathered the participants in this project for a discussion on the state of the art in HTGR fuel element development, graphite development, and waste management. The papers present an overview of work performed so far and an outlook on future tasks and goals, and on taking stock one can say that the project has been very successful so far: The HTGR fuel element now available meets highest requirements and forms the basis of today's HTGR safety philosophy; research work on graphite behaviour in a high-temperature reactor has led to complete knowledge of the temperature or neutron-induced effects, and with the concept of direct ultimate waste disposal, the waste management problem has found a feasible solution. (orig./GL)

  3. The supercontinent cycle

    Energy Technology Data Exchange (ETDEWEB)

    Nance, R.D.; Worsley, T.R.; Moody, J.B.

    1988-07-01

    This paper discusses a new theory of plate tectonics which proposes that Pangaea was only the most recent in a series of supercontinents that have been breaking up and reassembling every 500 million years or so. The cycle, driven by heat percolating up from the mantle, splits continents and drives interrelated processes that shape the earth's geology and climate and play a role in biological evolution. The framework of the supercontinent theory makes it possible to understand the timing of changes in sea level that have taken place in the past 570 million years, and also helps to explain periods of intense mountain building, episodes of glaciation, and changes in the nature of life on the earth.

  4. The uranium cycle

    International Nuclear Information System (INIS)

    In identifying uranium provinces, and, more importantly, mineralized zones within these provinces, it is of paramount importance to attempt to trace the geochemical behaviour of an element through all stages of Earth's evolution. Aspects that need to be addressed in this regard include solar abundance levels and fractionation processes during accretion, changing patterns of crustal evolution, effects of an evolving atmosphere, and the weathering cycle. Abundance patterns and partition coefficients of some of the siderophile elements in mantle rocks lend support to a multistage accretionary process. Lack of a terrestrial record in the first 500 Ma necessitates that lunar models be invoked, which suggests that early fractionation of a mafic/ultramafic magma resulted in an anorthositic crust. Fractionation of the mantle and transfer of materials to the upper levels must be central to any model invoked for development of the crust. Given high heat flow conditions in the early Archaean it would seem inescapable that the process of sea floor spreading and plate tectonics was an ongoing process. If the plate tectonic model is taken back to 3500 Ma, and assuming current speading rates, then about half of the mantle has passed through the irreversible differentiation cycle. Arguments in support of recycled material must be balanced against mantle metasomatism effects. With the associated advent of partial melting of the mantle material a partitioning of minor and trace elements into the melt fraction would take place. The early primitive mafic and ultramafic komatiites exemplify this feature by concentrating U and Th by a factor of 5 compared to chondritic abundances. It is of tantamount importance to understand the generation of the magmas in order to predict which are the 'fertile' bodies in terms of radioelement concentrations. In that the granitoid magmas image their source compositions, the association of high radioelements will primarily be source-dependent. Uranium

  5. Measurement of single cycle and sub-cycle pulse duration

    Institute of Scientific and Technical Information of China (English)

    Zhenglie Gong(龚正烈); Wenzhuo Ge(葛文卓); Guizhong Zhang(张贵忠); Wanghua Xiang(向望华)

    2004-01-01

    This paper suggests that the linear interferometric correlation (LFC) can be used to measure pulse duration of a few cycles, single cycle or even sub-cycle light pulse. The relations between pulsewidth and LFC curve are derived for Gaussian- and hyperbolic secant-shaped pules. This new method abandons focusing,frequency doubling and filtering in the traditional second order correlation method, meanwhile the signalto-noise ratio (SNR) is improved.

  6. Overview of cycling injuries: results of a cycling club survey.

    Science.gov (United States)

    Decalzi, Javier F; Narvy, Steven J; Vangsness, C Thomas

    2013-04-01

    Participation in competitive bicycling has increased substantially over the past decade, and bicycle injuries have increased accordingly. Cycling has been reported in several studies to have higher rates of injury than other sports and recreational activities; accordingly, riders must be cognizant of the potential for injury and protect themselves appropriately. The purpose of the current study was to survey an established competitive Los Angeles-based road cycling team to determine the epidemiology of and circumstances for traumatic cycling injuries.

  7. Removing Cycles in Esterel Programs

    Directory of Open Access Journals (Sweden)

    Reinhard von Hanxleden

    2007-05-01

    Full Text Available Esterel belongs to the family of synchronous programming languages, which are affected by cyclic signal dependencies. This prohibits a static scheduling, limiting the choice of available compilation techniques for programs with such cycles. This work proposes an algorithm that, given a constructive synchronous Esterel program, performs a semantics-preserving source code level transformation that removes cyclic signal dependencies. The transformation is divided into two parts: detection of cycles and iterative resolution of these cycles. It is based on the replacement of cycle signals by a signal expression involving no other cycle signals, thereby breaking the cycle. This transformation of cyclic Esterel programs enables the use of efficient compilation techniques, which are only available for acyclic programs. Furthermore, experiments indicate that the code transformation can even improve code quality produced by compilers that can already handle cyclic programs.

  8. Reproductive cycles of buffalo.

    Science.gov (United States)

    Perera, B M A O

    2011-04-01

    The domestic water buffalo (Bubalus bubalis) has an important role in the agricultural economy of many developing countries in Asia, providing milk, meat and draught power. It is also used in some Mediterranean and Latin American countries as a source of milk and meat for specialized markets. Although the buffalo can adapt to harsh environments and live on poor quality forage, reproductive efficiency is often compromised by such conditions, resulting in late sexual maturity, long postpartum anoestrus, poor expression of oestrus, poor conception rates and long calving intervals. The age at puberty is influenced by genotype, nutrition, management and climate, and under favourable conditions occurs at 15-18 months in river buffalo and 21-24 months in swamp buffalo. The ovaries are smaller than in cattle and contain fewer primordial follicles. Buffalo are capable of breeding throughout the year, but in many countries a seasonal pattern of ovarian activity occurs. This is attributed in tropical regions to changes in rainfall resulting in feed availability or to temperature stress resulting in elevated prolactin secretion, and in temperate regions to changes in photoperiod and melatonin secretion. The mean length of the oestrous cycle is 21 days, with greater variation than observed in cattle. The signs of oestrus in buffalo are less overt than in cattle and homosexual behaviour between females is rare. The duration of oestrus is 5-27 h, with ovulation occurring 24-48 h (mean 34 h) after the onset of oestrus. The hormonal changes occurring in peripheral circulation are similar to those observed in cattle, but the peak concentrations of progesterone and oestradiol-17β are less. The number of follicular waves during an oestrous cycle varies from one to three and influences the length of the luteal phase as well as the inter-ovulatory interval. Under optimal conditions, dairy types managed with limited or no suckling resume oestrus cyclicity by 30-60 days after calving

  9. Entrepreneurship and the business cycle

    OpenAIRE

    Thurik, Roy

    2014-01-01

    Entrepreneurship has a cyclical component, raising two questions. Is the entrepreneurship cycle related to the business cycle? And is there causality? A two-way relationship between entrepreneurship and the business cycle would be in line with the two faces of entrepreneurs: as agents of change creating upswings (opportunity entrepreneurship) and as rational actors escaping unemployment by setting up a business (necessity entrepreneurship). Nascent entrepreneurship can indeed be precyclical, ...

  10. Rethinking the Ancient Sulfur Cycle

    Science.gov (United States)

    Fike, David A.; Bradley, Alexander S.; Rose, Catherine V.

    2015-05-01

    The sulfur biogeochemical cycle integrates the metabolic activity of multiple microbial pathways (e.g., sulfate reduction, disproportionation, and sulfide oxidation) along with abiotic reactions and geological processes that cycle sulfur through various reservoirs. The sulfur cycle impacts the global carbon cycle and climate primarily through the remineralization of organic carbon. Over geological timescales, cycling of sulfur is closely tied to the redox state of Earth's exosphere through the burial of oxidized (sulfate) and reduced (sulfide) sulfur species in marine sediments. Biological sulfur cycling is associated with isotopic fractionations that can be used to trace the fluxes through various metabolic pathways. The resulting isotopic data provide insights into sulfur cycling in both modern and ancient environments via isotopic signatures in sedimentary sulfate and sulfide phases. Here, we review the deep-time δ34S record of marine sulfates and sulfides in light of recent advances in understanding how isotopic signatures are generated by microbial activity, how these signatures are encoded in marine sediments, and how they may be altered following deposition. The resulting picture shows a sulfur cycle intimately coupled to ambient carbon cycling, where sulfur isotopic records preserved in sedimentary rocks are critically dependent on sedimentological and geochemical conditions (e.g., iron availability) during deposition.

  11. Regenerative superheated steam turbine cycles

    Science.gov (United States)

    Fuller, L. C.; Stovall, T. K.

    1980-01-01

    PRESTO computer program was developed to analyze performance of wide range of steam turbine cycles with special attention given to regenerative superheated steam turbine cycles. It can be used to model standard turbine cycles, including such features as process steam extraction, induction and feedwater heating by external sources, peaking, and high back pressure. Expansion line efficiencies, exhaust loss, leakages, mechanical losses, and generator losses are used to calculate cycle heat rate and generator output. Program provides power engineer with flexible aid for design and analysis of steam turbine systems.

  12. Organic rankine cycle fluid

    Science.gov (United States)

    Brasz, Joost J.; Jonsson, Ulf J.

    2006-09-05

    A method of operating an organic rankine cycle system wherein a liquid refrigerant is circulated to an evaporator where heat is introduced to the refrigerant to convert it to vapor. The vapor is then passed through a turbine, with the resulting cooled vapor then passing through a condenser for condensing the vapor to a liquid. The refrigerant is one of CF.sub.3CF.sub.2C(O)CF(CF.sub.3).sub.2, (CF.sub.3).sub.2 CFC(O)CF(CF.sub.3).sub.2, CF.sub.3(CF.sub.2).sub.2C(O)CF(CF.sub.3).sub.2, CF.sub.3(CF.sub.2).sub.3C(O)CF(CG.sub.3).sub.2, CF.sub.3(CF.sub.2).sub.5C(O)CF.sub.3, CF.sub.3CF.sub.2C(O)CF.sub.2CF.sub.2CF.sub.3, CF.sub.3C(O)CF(CF.sub.3).sub.2.

  13. The earth's hydrological cycle

    CERN Document Server

    Bonnet, R-M; Calisto, M; Destouni, G; Gurney, R; Johannessen, J; Kerr, Y; Lahoz, WA; Rast, M

    2014-01-01

    This book gives a comprehensive presentation of our present understanding of the Earth's Hydrological cycle and the problems, consequences and impacts that go with this topic. Water is a central component in the Earth's system. It is indispensable for life on Earth in its present form and influences virtually every aspect of our planet's life support system. On relatively short time scales, atmospheric water vapor interacts with the atmospheric circulation and is crucial in forming the Earth's climate zones. Water vapor is the most powerful of the greenhouse gases and serves to enhance the tropospheric temperature. The dominant part of available water on Earth resides in the oceans. Parts are locked up in the land ice on Greenland and Antarctica and a smaller part is estimated to exist as groundwater. If all the ice over the land and all the glaciers were to melt, the sea level would rise by some 80 m. In comparison, the total amount of water vapor in the atmosphere is small; it amounts to ~ 25 kg/m2, or the ...

  14. Biomass Gasification Combined Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Judith A. Kieffer

    2000-07-01

    Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

  15. The closed fuel cycle

    International Nuclear Information System (INIS)

    Available in abstract form only. Full text of publication follows: The fast growth of the world's economy coupled with the need for optimizing use of natural resources, for energy security and for climate change mitigation make energy supply one of the 21. century most daring challenges. The high reliability and efficiency of nuclear energy, its competitiveness in an energy market undergoing a new oil shock are as many factors in favor of the 'renaissance' of this greenhouse gas free energy. Over 160,000 tHM of LWR1 and AGR2 Used Nuclear Fuel (UNF) have already been unloaded from the reactor cores corresponding to 7,000 tons discharged per year worldwide. By 2030, this amount could exceed 400,000 tHM and annual unloading 14,000 tHM/year. AREVA believes that closing the nuclear fuel cycle through the treatment and recycling of Used Nuclear Fuel sustains the worldwide nuclear power expansion. It is an economically sound and environmentally responsible choice, based on the preservation of natural resources through the recycling of used fuel. It furthermore provides a safe and secure management of wastes while significantly minimizing the burden left to future generations. (authors)

  16. Post-critical behavior of Beck`s column with a tip mass

    DEFF Research Database (Denmark)

    Andersen, S. B.; Thomsen, Jon Juel

    2002-01-01

    by linear theory. A similar change in bifurcation is found to occur with increased external (as compared to internal) damping, and with a shortening in column length. These effects are not revealed by linear modeling and analysis, which may consequently fail to predict even qualitatively the real critical...... oscillations. Bifurcation diagrams are given, showing how the vibration amplitude changes with follower load and other parameters. These results agree closely with numerical simulation. It is found that sufficiently large values of tip mass rotary inertia can change the primary bifurcation from supercritical...

  17. Ulrich Beck : riskiühiskond / Ulrich Beck ; tõlk. Külli-Riin Tigasson

    Index Scriptorium Estoniae

    Beck, Ulrich

    2004-01-01

    Katkend raamatust "Risikogesellschaft". Autori hinnangul on tänapäeval poliitikute roll ühiskonna arengu otsustamisel kahanenud, sest võtmelise tähtsusega otsuseid teevad teadlased ja äriühingute juhid. Poliitika ja mittepoliitika vahetavad kohad

  18. Life Cycle of Stars

    Science.gov (United States)

    1999-01-01

    In this stunning picture of the giant galactic nebula NGC 3603, the crisp resolution of NASA's Hubble Space Telescope captures various stages of the life cycle of stars in one single view. To the upper left of center is the evolved blue supergiant called Sher 25. The star has a unique circumstellar ring of glowing gas that is a galactic twin to the famous ring around the supernova 1987A. The grayish-bluish color of the ring and the bipolar outflows (blobs to the upper right and lower left of the star) indicates the presence of processed (chemically enriched) material. Near the center of the view is a so-called starburst cluster dominated by young, hot Wolf-Rayet stars and early O-type stars. A torrent of ionizing radiation and fast stellar winds from these massive stars has blown a large cavity around the cluster. The most spectacular evidence for the interaction of ionizing radiation with cold molecular-hydrogen cloud material are the giant gaseous pillars to the right of the cluster. These pillars are sculptured by the same physical processes as the famous pillars Hubble photographed in the M16 Eagle Nebula. Dark clouds at the upper right are so-called Bok globules, which are probably in an earlier stage of star formation. To the lower left of the cluster are two compact, tadpole-shaped emission nebulae. Similar structures were found by Hubble in Orion, and have been interpreted as gas and dust evaporation from possibly protoplanetary disks (proplyds). This true-color picture was taken on March 5, 1999 with the Wide Field Planetary Camera 2.

  19. The LifeCycle model

    DEFF Research Database (Denmark)

    Krink, Thiemo; Løvbjerg, Morten

    2002-01-01

    Adaptive search heuristics are known to be valuable in approximating solutions to hard search problems. However, these techniques are problem dependent. Inspired by the idea of life cycle stages found in nature, we introduce a hybrid approach called the LifeCycle model that simultaneously applies...

  20. Nuclear fuel cycle information workshop

    International Nuclear Information System (INIS)

    This overview of the nuclear fuel cycle is divided into three parts. First, is a brief discussion of the basic principles of how nuclear reactors work; second, is a look at the major types of nuclear reactors being used and world-wide nuclear capacity; and third, is an overview of the nuclear fuel cycle and the present industrial capability in the US

  1. Economic growth and business cycles

    NARCIS (Netherlands)

    Canton, E.J.F.

    1997-01-01

    This thesis contains five essays on economic growth and business cycles. The main focus is on the interaction between economic growth and the cycle: is cyclical variability good or bad for the long-run rate of economic growth? The introduction aims to provide some empirical evidence for an investmen

  2. Variations on the Zilch Cycle

    Science.gov (United States)

    Binder, P.-M.; Tanoue, C. K. S.

    2013-01-01

    Thermo dynamic cycles in introductory physics courses are usually made up from a small number of permutations of isothermal, adiabatic, and constant-pressure and volume quasistatic strokes, with the working fluid usually being an ideal gas. Among them we find the Carnot, Stirling, Otto, Diesel, and Joule-Brayton cycles; in more advanced courses,…

  3. The water cycle for kids

    Science.gov (United States)

    Neno, Stephanie; Morgan, Jim; Zonolli, Gabriele; Perlman, Howard; Gonthier, Gerard

    2013-01-01

    The U.S. Geological Survey (USGS) and the Food and Agriculture Organization of the United Nations (FAO) have created a water-cycle diagram for use in elementary and middle schools. The diagram is available in many languages. This diagram is part of the USGS's Water Science School, in which the water cycle is described in detail.

  4. Activity Cycle of Solar Filaments

    Indian Academy of Sciences (India)

    K. J. Li; Q. X. Li; P. X. Gao; J. Mu; H. D. Chen; T. W. Su

    2007-06-01

    Long-term variation in the distribution of the solar filaments observed at the Observatorie de Paris, Section de Meudon from March 1919 to December 1989 is presented to compare with sunspot cycle and to study the periodicity in the filament activity, namely the periods of the coronal activity with the Morlet wavelet used. It is inferred that the activity cycle of solar filaments should have the same cycle length as sunspot cycle, but the cycle behavior of solar filaments is globally similar in profile with, but different in detail from, that of sunspot cycles. The amplitude of solar magnetic activity should not keep in phase with the complexity of solar magnetic activity. The possible periods in the filament activity are about 10.44 and 19.20 years. The wavelet local power spectrum of the period 10.44 years is statistically significant during the whole consideration time. The wavelet local power spectrum of the period 19.20 years is under the 95% confidence spectrum during the whole consideration time, but over the mean red-noise spectrum of = 0.72 before approximate Carrington rotation number 1500, and after that the filament activity does not statistically show the period. Wavelet reconstruction indicates that the early data of the filament archive (in and before cycle 16) are more noiseful than the later (in and after cycle 17).

  5. Study on diet-related behavior of pupils in Kaschin-Beck disease endemic areas of Xi'an City%西安市大骨节病区小学生饮食行为研究

    Institute of Scientific and Technical Information of China (English)

    陈伟; 柳明; 时学花; 李平; 靳玲; 董璐; 姚培杰; 杨钢; 谢龙

    2015-01-01

    目的 了解西安市大骨节病区小学生饮食行为情况,为大骨节病病因研究和防治提供科学依据.方法 采用分层随机整群抽样法,用自行设计的问卷对1 076名小学生进行自填式问卷调查.结果 调查对象中当地小麦的食用率为78.81%,其次为外地大米(58.92%)和当地玉米(52.51%).调查对象中坚持食用大米的行为率为51.30%,食用富硒食品的行为率为21.28%;中、重病区食用大米和富硒食品的行为率均低于轻病区(x2=9.351、54.818,均P<0.05).五年级学生坚持食用大米和富硒食品的行为率高于三年级(x2=17.104、6.262,均P<0.05).50.93%的调查对象愿意食用大米,24.67%的调查对象愿意食用富硒食物.四、五年级学生食用大米的意愿高于三年级(x2=19.384,P<0.05),轻病区学生食用富硒食物的意愿高于重中病区(x2=33.331,P<0.05).病区学生最近1周内副食食用情况中蔬菜(73.04%)、新鲜水果(57.43%)和奶及奶制品(44.05%)食用率较高,而家禽及禽产品(18.40%)、猪牛羊肉(15.33%)、鱼类(13.01%)较低.结论 西安市大骨节病病区小学生的饮食行为不合理,存在主食种类单一,以当地小麦、玉米为主,肉类、家禽、鱼类等食用率偏低的情况.相关部门应加强对病区居民大骨节病防治知识的健康教育,促进居民改善不良的饮食行为,提高病区儿童身体素质.%[Objective] To understand the diet-related behavior of pupils in Kaschin-Beck disease (KBD) endemic areas of Xi'an City,provide a scientific basis for etiological study and prevention of KBD.[Methods] Using the stratified random cluster sampling method,the self-administered questionnaire survey was performed among 1076 pupils with a self-designed questionnaire.[Results] The consumption rate of local wheat among respondents was 78.81%,followed by the nonlocal rice (58.92%) and local corn (52.51%).51.30% of respondents insisted on eating rice

  6. Analysis on surveillance results of Kaschin-Beck disease from monitoring site in Henan Province in 2008%2008年河南省大骨节病病情调查结果与分析

    Institute of Scientific and Technical Information of China (English)

    崔才磊; 于红阳; 岳义田

    2009-01-01

    目的 了解河南省大骨节病病情现状,为大骨节病防治提供依据.方法 2008年在河南省大骨节病病区选择地形、地貌、生产及生活方式上具有代表性的陕县张村乡窑店、庙洼村,灵宝市朱阳镇朱阳村进行7~12岁儿童大骨节病临床调查,同时拍右手X线片和采集部分儿童发样和当地粮样.儿童发硒、粮食硒测定采用2,3-二氨基萘荧光法.在洛宁县、灵宝市、渑池县、陕县、卢氏县大骨节病病区乡进行16岁以上成人大骨节病病情调查.结果 共检查7~12岁儿童190人,未检出大骨节病临床病例;拍摄右手X线片190人,X线阳性3人.检出率为1.58%(3/190).共调查16岁及以上的常住人口20 521人,大骨节病临床检出率为6.10%(1251/20 521),其中Ⅰ度为3.97%(814/20 521),Ⅱ度为1.77%(364/20 521),Ⅲ度为0.36%(73/20 521).儿童发硒平均值为(0.319±0.128)mg/kg,粮食硒平均值为(0.031±0.009)mg/kg.结论 河南省儿童大骨节病处于控制水平,成人大骨节病病情较为严重,应加强以治疗现患病人为目的的二级预防.%Objective To understand Kaschin-Beck disease(KBD) status in Henan Province and provide the basis for the further prevention and treatment of KBD. Methods Children aged 7 to 12 in 3 villages(Yaodian, Miaowa and Zhuyang) with the same environment such as topography, physiognomy,production mode and living habits in Shan County and Lingbao City were selected to undertake KBD clinical examination in 2008, X-ray examination of right hand and child hair samples and food samples were collected to determine the content of selenium. Selenium was determined using 2,3-Diaminonaphthalene method. Adults who were 16 years or older in 5 counties(Luoning, Lingbao, Mianchi, Shah and Lushi) were selected and examined for KBD. Results One hundred and ninty children aged 7 to 12 were clinically examined and clinical KBD were found, whereas 3 children were diagnosed as KBD by X-ray examination, the

  7. 不同补硒方式防治大骨节病的系统评价%A systematic review regarding the effects of different kinds of selenium supplementations on Kaschin-Beck disease

    Institute of Scientific and Technical Information of China (English)

    时春虎; 田宏亮; 田金徽; 曾嵘; 杨克虎; 吴泰相; 廖永健

    2013-01-01

    目的 系统评价大骨节病病区不同补硒方式对患病儿童的防治效果.方法 计算机系统检索各中外文数据库及搜索引擎.全面收集有关各种补硒方法防治大骨节病的对照研究,检索时间截至2012年12月.对纳入研究进行质量评价,采用RevMan 5.1软件进行Meta分析.结果 最终纳入14个随机对照试验,12个非随机对照试验,方法学质量均较低.Meta分析结果显示,与安慰剂或空白对照相比,单独补硒治疗能提高大骨节病患儿的X线有效率(RR=3.28,95%CI:2.06~5.22)及发硒水平(SMD=2.05,95%CI:1.00~ 3.11),且能降低新发病例(OR=0.18,95%CI:0.09~ 0.36);单独补硒与单独补充维生素C的X线干骺端好转率的差异无统计学意义(RR=1.01,95%CI:0.84~1.22);补硒联合维生素E治疗的X线有效率及发硒水平高于安慰剂组;与单独补硒相比,补硒联合维生素C在X线疗效和发硒水平上无明显差异;富硒酵母组的有效率(70.83%)高于亚硒酸钠(48.84%)(P<0.05);施硒肥组的X线有效率高于空白组(RR=3.98,95%CI:2.25~7.05),综合干预及晒粮等方法亦有一定效果.结论 单独补硒可提高大骨节病患者X线有效率和发硒水平;维生素联合补硒效果优于单独补硒;富硒酵母的疗效优于单独补硒和对照组.%Objective To systematically assess the efficacy of different programs regarding the selenium supplementation formulae used for prevention and treatment of Kaschin-Beck disease (KBD) in children.Methods PubMed,EMBASE,Cochrane Library,SCI expanded,CNKI (Chinese National Knowledge Infrastructure),VIP (Chinese Science and Technique Journals Database),CBM (The Chinese Biomedical Database),Wanfang Database,CSCD (Chinese Science Citation Database)had been electronically searched.All the searching processes were up-dated to Dec 2012 to identify randomized trials (RCTs) and non-RCTs to compare the selenium supplementation formulae with placebo or with no

  8. Prospects for Predicting Cycle 24

    Indian Academy of Sciences (India)

    Arnab Rai Choudhuri

    2008-03-01

    Although we have reliable data of solar polar fields only from the mid-1970s, it seems that the polar field at a minimum is well correlated with the next cycle, but the strength of the cycle is not correlated with the polar field produced at its end. We explain this by suggesting that the Babcock–Leighton mechanism of poloidal field generation from tilted active regions involves randomness, whereas the other aspects of the dynamo process are more ordered. To model actual cycles, we have to ‘correct’ our theoretical dynamo model by ‘feeding’ information about the polar field at the minima. Following this process, we find that our model fits the observed sunspot numbers of cycles 21–23 reasonably well and predicts that cycle 24 will be the weakest in a century.

  9. Limit cycles in quantum systems

    Energy Technology Data Exchange (ETDEWEB)

    Niemann, Patrick

    2015-04-27

    In this thesis we investigate Limit Cycles in Quantum Systems. Limit cycles are a renormalization group (RG) topology. When degrees of freedom are integrated out, the coupling constants flow periodically in a closed curve. The presence of limit cycles is restricted by the necessary condition of discrete scale invariance. A signature of discrete scale invariance and limit cycles is log-periodic behavior. The first part of this thesis is concerned with the study of limit cycles with the similarity renormalization group (SRG). Limit cycles are mainly investigated within conventional renormalization group frameworks, where degrees of freedom, which are larger than a given cutoff, are integrated out. In contrast, in the SRG potentials are unitarily transformed and thereby obtain a band-diagonal structure. The width of the band structure can be regarded as an effective cutoff. We investigate the appearance of limit cycles in the SRG evolution. Our aim is to extract signatures as well as the scaling factor of the limit cycle. We consider the 1/R{sup 2}-potential in a two-body system and a three-body system with large scattering lengths. Both systems display a limit cycle. Besides the frequently used kinetic energy generator we apply the exponential and the inverse generator. In the second part of this thesis, Limit Cycles at Finite Density, we examine the pole structure of the scattering amplitude for distinguishable fermions at zero temperature in the medium. Unequal masses and a filled Fermi sphere for each fermion species are considered. We focus on negative scattering lengths and the unitary limit. The properties of the three-body spectrum in the medium and implications for the phase structure of ultracold Fermi gases are discussed.

  10. Mechanistic exploration of the catalytic cycles for the CO oxidation by O2 over FeO(1-3) application of the energetic span model.

    Science.gov (United States)

    Wang, Huan-Jiang; Wang, Yong-Cheng

    2014-06-01

    Carbon monoxide (CO) and oxygen (O2) catalyzed by small neutral iron oxide clusters (FeO(1-3)) was investigated at the density functional level of theory using the Becke-Perdew-Wang functional (BPW91). Three reaction pathways along with singlet, triplet and quintet states were calculated for ascertaining the presence of some spin inversion during the catalytic cycle. The catalytic cycle was found to be "two state reactivity" resulting from the crossing among the multistate energetic profiles. The Landau-Zener equation was used to calculate the thermally-averaged spin transition probabilities for the non-adiabatic surface crossing reaction. In order to predict the efficiency of catalyst the energetic span model developed by Kozuch was implemented, whereas this model is not suitable for handling the diabatic reaction, this feature we must take into consideration. To this end, a kinetic assessment is carried out with an expansion of the energetic span model, including the spin-crossing effects. This approximation enables one to measure the efficiency of catalytic cycle including spin-crossing effects by quantum mechanical computation.

  11. Life cycle of mobile devices

    Directory of Open Access Journals (Sweden)

    T.V. Rohal

    2011-12-01

    Full Text Available Article is devoted features of life cycle of mobile devices. The article highlighted a number of disadvantages associated with managing the life cycle of the product. Disadvantages include the orientation is not on the quality of mobile devices and their design, the obsolescence of digital products. The article drew attention to the need for process improvement life cycle management of mobile devices. For since this type of product is now the most popular among the population, consumers are interested, first of all, quality, and only then, look good.

  12. Introducing Life Cycle Impact Assessment

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Huijbregts, Mark AJ

    2015-01-01

    methodology projects and presents the international scientific discussions and methodological consensus attempts in consecutive working groups under the auspices of the Society of Environmental Toxicology and Chemistry (SETAC) as well as the UNEP/ SETAC Life Cycle Initiative, and the (almost) parallel......This chapter serves as an introduction to the presentation of the many aspects of life cycle impact assessment (LCIA) in this volume of the book series ‘LCA Compendium’. It starts with a brief historical overview of the development of life cycle impact assessment driven by numerous national LCIA...

  13. Prospects for predicting cycle 24

    OpenAIRE

    Choudhuri, Arnab Rai

    2008-01-01

    Although we have reliable data of solar polar fields only from the mid-1970s, it seems that the polar field at a minimum is well correlated with the next cycle, but the strength of the cycle is not correlated with the polar field produced at its end. We explain this by suggesting that the Babcock–Leighton mechanism of poloidal field generation from tilted active regions involves randomness, whereas the other aspects of the dynamo process are more ordered. To model actual cycles, we have to 'c...

  14. (Auto)Ethnographies and Cycling

    DEFF Research Database (Denmark)

    Larsen, Jonas

    2014-01-01

    , habits and affective capacities of cycling are cultivated and performed. The article argues that autoethnography is particularly apt at illuminating the embodied qualities of movement, and it sits within established ethnographies of ‘excising’ and ‘mobile bodies’. In the second part of the article, I...... draw upon ongoing autoethnographies of cycling in a familiar place (my hometown, Copenhagen) and by learning to cycle ‘out-of-place’ (in London) and ‘in-a-new–way’ (when commuting long distance on a racer bike). The study challenges static notions of the body by analysing how cyclists’ (and researchers...

  15. BWROPT: A multi-cycle BWR fuel cycle optimization code

    Energy Technology Data Exchange (ETDEWEB)

    Ottinger, Keith E.; Maldonado, G. Ivan, E-mail: Ivan.Maldonado@utk.edu

    2015-09-15

    Highlights: • A multi-cycle BWR fuel cycle optimization algorithm is presented. • New fuel inventory and core loading pattern determination. • The parallel simulated annealing algorithm was used for the optimization. • Variable sampling probabilities were compared to constant sampling probabilities. - Abstract: A new computer code for performing BWR in-core and out-of-core fuel cycle optimization for multiple cycles simultaneously has been developed. Parallel simulated annealing (PSA) is used to optimize the new fuel inventory and placement of new and reload fuel for each cycle considered. Several algorithm improvements were implemented and evaluated. The most significant of these are variable sampling probabilities and sampling new fuel types from an ordered array. A heuristic control rod pattern (CRP) search algorithm was also implemented, which is useful for single CRP determinations, however, this feature requires significant computational resources and is currently not practical for use in a full multi-cycle optimization. The PSA algorithm was demonstrated to be capable of significant objective function reduction and finding candidate loading patterns without constraint violations. The use of variable sampling probabilities was shown to reduce runtime while producing better results compared to using constant sampling probabilities. Sampling new fuel types from an ordered array was shown to have a mixed effect compared to random new fuel type sampling, whereby using both random and ordered sampling produced better results but required longer runtimes.

  16. Life-cycle cost analysis of adsorption cycles for desalination

    KAUST Repository

    Thu, Kyaw

    2010-08-01

    This paper presents the thermo-economic analysis of the adsorption desalination (AD) cycle that is driven by low-temperature waste heat from exhaust of industrial processes or renewable sources. The AD cycle uses an adsorbent such as the silica gel to desalt the sea or brackish water. Based on an experimental prototype AD plant, the life-cycle cost analysis of AD plants of assorted water production capacities has been simulated and these predictions are translated into unit cost of water production. Our results show that the specific energy consumption of the AD cycle is 1.38 kWh/m3 which is the lowest ever reported. For a plant capacity of 1000 m3/d, the AD cycle offers a unit cost of $0.457/m3 as compared to more than $0.9 for the average RO plants. Besides being cost-effective, the AD cycle is also environment-friendly as it emits less CO2 emission per m3 generated, typically 85% less, by comparison to an RO process. © 2010 Desalination Publications.

  17. A retrospective analysis of Kashin-Beck disease f rom 1982 to 2011 in Qinghai Province%青海省大骨节病30年防治状况分析

    Institute of Scientific and Technical Information of China (English)

    张强; 王虎; 陈黎林; 丁生荣; 李强; 赵志军; 白生录; 马静

    2014-01-01

    Objective To summarize the date of surveillance ,investigation ,prevention and research on Kash-in-Beck disease (KBD) among children from the year 1982 through 2011 in KBD regions of Qinghai Province ,in or-der to analyze the growth and decline of KBD occurrence ,development and influencing factors .Methods Survey was conducted among children with reference to the standard diagnosis of KBD .The internal and external environ-ment of trace elements including selenium ,iodine and fluorine were detected .Food T-2 toxins were determined ac-cording to the national standard method .Results The KBD prevalence rate and the X-ray detectable rate were 2.50~17 .39% ,0~13 .73% ;1 .21~8 .24% ,6 .70~23 .28% ;and 4 .26~26 .14% ,0 .80~3 .46% in Guide County , Xinghai County ,and Banma County ,respectively .The hair selenium of children rose from (57 .00 ± 48 .12)μg/kg in 1982 to (182 .09 ± 78 .46)μg/kg in 2010 in Guide County .The hair selenium of children rose from (70 .34 ± 60 .97)μg/kg in 1989 to (211 .80 ± 86 .84)μg/kg in 2010 in Xinghai County according to single factor analysis of variance (F test) ,(P<0 .05) .The hair selenium level of children in Banma County was stable and higher than that in Guide County and Xinghai County according to F test ,(P=0 .05) .Water ,soil ,household produced food selenium level was low and stable in Guide County and Xinghai County .Water ,soil ,grain selenium level in Banma County was higher than that in Guide and Xinghai ,according to F test ,( P<0 .05 ) .Salt iodine and urinary iodine levels were within the normal range in Guide County and Xinghai County ,but water iodine was lower than the national stand-ard .In Xinghai County ,the T-2 toxin in household produced food was exceedingly high .In Guide County ,the fluo-rine content of external environment was below the non -endemic area ,and the content of fluorine in children was higher than that in children in non -endemic area .Conclusions The prevalence rate declined with

  18. Beck Robert et Madoeuf Anna, Divertissements et loisirs dans les sociétés urbaines à l’époque moderne et contemporaine, Tours, Presses universitaires François Rabelais et Maison des Sciences de l’Homme, 2005, 410 p.

    Directory of Open Access Journals (Sweden)

    Francine Fourmaux

    2007-11-01

    Full Text Available Comment prend-on du bon temps dans les sociétés urbaines, à l’époque moderne et contemporaine ? Telle est la question à laquelle plus d’une vingtaine de chercheurs ont consacré leurs analyses, rassemblées dans cet ouvrage par Robert Beck et Anna Madoeuf à la suite du colloque international et pluridisciplinaire « Divertissements et loisirs dans les sociétés urbaines, une approche comparative monde occidental – monde musulman » qu’ils ont organisé à Tours en 2003. L’historien Alain Corbin l’a ...

  19. Corporate governance cycles during transition

    DEFF Research Database (Denmark)

    Mygind, Niels; Demina, Natalia; Gregoric, Aleksandra;

    2004-01-01

    -nancial system. To provide simple hypothesis tests, we use Russian enterprise data for 1995-2003 and Slovenian data covering 1998-2003. In spite of differences in institutional development, con-cerning privatization and development of corporate governance institutions, we find that govern-ance cycles are broadly...... of ownership on managers, external domestic and foreign owners. JEL-codes: G3, J5, P2, P3 - Keywords: corporate governance, life-cycle, privatization, ownership change, transition economies, Russia and Slovenia.......Ownership is determined by firm specific factors and the environment. Firms change over their life-cycle. The governance cycle - here defined as changes in identity of the dominant owner and own-ership concentration - is marked by key phases including start-up, growth, and possibly a restructur...

  20. Revenue cycle management, Part II.

    Science.gov (United States)

    Crew, Matt

    2007-01-01

    The proper management of your revenue cycle requires the application of "best practices" and the continual monitoring and measuring of the entire cycle. The correct technology will enable you to gain the insight and efficiencies needed in the ever-changing healthcare economy. The revenue cycle is a process that begins when you negotiate payor contracts, set fees, and schedule appointments and continues until claims are paid in full. Every single step in the cycle carries equal importance. Monitoring all phases and a commitment to continually communicating the results will allow you to achieve unparalleled success. In part I of this article, we explored the importance of contracting, scheduling, and case management as well as coding and clinical documentation. We will now take a closer look at the benefits charge capture, claim submission, payment posting, accounts receivable follow-up, and reporting can mean to your practice.

  1. Total Product Life Cycle (TPLC)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Total Product Life Cycle (TPLC) database integrates premarket and postmarket data about medical devices. It includes information pulled from CDRH databases...

  2. Mirador - Carbon Cycle and Ecosystems

    Data.gov (United States)

    National Aeronautics and Space Administration — Earth Science data access made simple. This Focus Area deals with the cycling of carbon in reservoirs and ecosystems as it changes naturally, is changed by humans,...

  3. Mirador - Water and Energy Cycles

    Data.gov (United States)

    National Aeronautics and Space Administration — Earth Science data access made simple. Through water and energy cycle research we can improve hurricane prediction, quantify tropical rainfall and eventually begin...

  4. Cycling in multimodal transport behaviours

    DEFF Research Database (Denmark)

    Olafsson, Anton Stahl; Nielsen, Thomas Sick; Carstensen, Trine Agervig

    2016-01-01

    explores how cycling forms part of multimodal transport behaviour based on survey data on transport modes and travel purposes and the weekly frequency of out-of-home activities and travel mode use in a representative sample of adult Danes (n = 1957). The following five distinct multimodal travel segments......Multimodality is important for achieving less car dependent lifestyles and more sustainable transport behaviours. It is widely recognised that cycling plays a prominent role in sustainable transport. However, research has largely focused on cycling substituting motorised transport. This study...... or 'modality styles' are identified: 'education transport'; 'public-based transport'; 'limited transport'; 'bicycle-based transport'; and 'car-based transport'. Travel behaviour is predominantly multimodal with few unimodal car-drivers being identified. Substantial cycling takes place in all modality styles...

  5. Towards Life Cycle Sustainability Assessment

    Directory of Open Access Journals (Sweden)

    Marzia Traverso

    2010-10-01

    Full Text Available Sustainability is nowadays accepted by all stakeholders as a guiding principle for both public policy making and corporate strategies. However, the biggest challenge for most organizations remains in the real and substantial implementation of the sustainability concept. The core of the implementation challenge is the question, how sustainability performance can be measured, especially for products and processes. This paper explores the current status of Life Cycle Sustainability Assessment (LCSA for products and processes. For the environmental dimension well established tools like Life Cycle Assessment are available. For the economic and social dimension, there is still need for consistent and robust indicators and methods. In addition to measuring the individual sustainability dimensions, another challenge is a comprehensive, yet understandable presentation of the results. The “Life Cycle Sustainability Dashboard” and the “Life Cycle Sustainability Triangle” are presented as examples for communication tools for both experts and non expert stakeholders.

  6. Venus Altitude Cycling Balloon Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The ISTAR Group ( IG) and team mate Thin Red Line Aerospace (TRLA) propose a Venus altitude cycling balloon (Venus ACB), an innovative superpressure balloon...

  7. Endogenous, Imperfectly Competitive Business Cycles

    DEFF Research Database (Denmark)

    Whitta-Jacobsen, Hans Jørgen

    We investigate how imperfect competition affects the occurrence and the properties of endogenous, rational expectations business cycles in an overlapping generations model with constant returns to scale in production. The model has explicit product and labor markets all characterized...... by monopolistic competition. An implicit assumption of barriers to entry justifies that the number of firms is fixed even when positive profits occur. It turns out that both market power of firms on the product markets and market power of unions on the labor markets make the occurrence of cycles more likely....... In particular, imperfect competition on the product markets and the positive profits associated with it may have the effect that there is a cycle even if the labor supply curve is increasing in the real-wage rate. For competitive cycles is required not only a decreasing labor supply curve, but a wage elasticity...

  8. Stability ordering of cycle expansions

    CERN Document Server

    Dettmann, C P

    1997-01-01

    We propose that cycle expansions be ordered with respect to stability rather than orbit length for many chaotic systems, particularly those exhibiting crises. This is illustrated with the strong field Lorentz gas, where we obtain significant improvements over traditional approaches.

  9. Glacial Cycles and Milankovitch Forcing

    CERN Document Server

    Raghuraman, Shiv Priyam

    2015-01-01

    Using a recent conceptual model of the glacial-interglacial cycles we present more evidence of Milankovitch cycles being the trigger for retreat and forming of ice sheets in the cycles. This model is based on a finite approximation of an infinite dimensional model which has three components: Budyko's energy balance model describing the annual mean temperatures at latitudes, Widiasih's ODE which describes the behavior of the edge of the ice sheet, and Walsh et al. who introduced a snow line to account for glacial accumulation and ablation zones. Certain variables in the model are made to depend on the Milankovitch cycles, in particular, the obliquity of the Earth's axis and the eccentricity of the Earth's orbit. We see as a result that deglaciation and glaciation do occur mostly due to obliquity and to some extent eccentricity.

  10. On acyclicity of games with cycles

    DEFF Research Database (Denmark)

    Andersson, Klas Olof Daniel; Hansen, Thomas Dueholm; Gurvich, Vladimir

    2010-01-01

    We study restricted improvement cycles (ri-cycles) in finite positional n-person games with perfect information modeled by directed graphs (di-graphs) that may contain directed cycles (di-cycles). We assume that all these di-cycles form one outcome c, for example, a draw. We obtain criteria of re...

  11. Detonation Jet Engine. Part 1--Thermodynamic Cycle

    Science.gov (United States)

    Bulat, Pavel V.; Volkov, Konstantin N.

    2016-01-01

    We present the most relevant works on jet engine design that utilize thermodynamic cycle of detonative combustion. The efficiency advantages of thermodynamic detonative combustion cycle over Humphrey combustion cycle at constant volume and Brayton combustion cycle at constant pressure were demonstrated. An ideal Ficket-Jacobs detonation cycle, and…

  12. No News in Business Cycles

    OpenAIRE

    Forni, Mario; Gambetti, Luca; Sala, Luca

    2011-01-01

    This paper uses a structural, large dimensional factor model to evaluate the role of 'news' shocks (shocks with a delayed effect on productivity) in generating the business cycle. We find that (i) existing small-scale VECM models are affected by 'non-fundamentalness' and therefore fail to recover the correct shock and impulse response functions; (ii) news shocks have a limited role in explaining the business cycle; (iii) their effects are in line with what predicted by standard neoclassical t...

  13. Business Cycle Theory and Econometrics

    OpenAIRE

    Allan W. Gregory; Smith, Gregor W.

    1995-01-01

    We outline in turn criticisms made by econometricians of the methods used in empirical business-cycle research and then criticisms made by business-cycle researchers of some methods used by econometricians. The aim is to clarify and in some cases correct these criticisms. Overall there is no conflict in using rigourous statistical procedures to study modern dynamic stochastic general equilibrium models. We also provide a concise bibliography of recent research on statistical methods for busin...

  14. Limit cycles of effective theories

    OpenAIRE

    Glazek, Stanislaw D.

    2006-01-01

    A simple example is used to show that renormalization group limit cycles of effective quantum theories can be studied in a new way. The method is based on the similarity renormalization group procedure for Hamiltonians. The example contains a logarithmic ultraviolet divergence that is generated by both real and imaginary parts of the Hamiltonian matrix elements. Discussion of the example includes a connection between asymptotic freedom with one scale of bound states and the limit cycle with a...

  15. Social learning and innovation cycles

    OpenAIRE

    Garfagnini, Umberto; Strulovici, Bruno

    2012-01-01

    We study social learning and innovation in an overlapping generations model, emphasizing the trade-off between marginal innovation (combining existing technologies) and radical innovation (breaking new ground). We characterize both short-term and long-term dynamics of innovation, and the intergenerational accumulation of knowledge. Innovation cycles emerge endogenously, but the number of cycles is finite almost surely, and radical innovation terminates in finite time. We identify a negative r...

  16. Animal spirits and business cycles

    OpenAIRE

    Bidder, Rhys

    2015-01-01

    Animal spirits are often suggested as a cause of business cycles, but they are very difficult to define. Recent research proposes a novel explanation based on the changing level of risk over time and people’s uncertainty about how the world works. The interaction of these two can lead to significant business cycle fluctuations in response to spikes in volatility. This finding gives researchers an alternative to irrational behavior as an explanation for why swings in consumer sentiment appear ...

  17. The NEWS Water Cycle Climatology

    Science.gov (United States)

    Rodell, Matthew; Beaudoing, Hiroko Kato; L'Ecuyer, Tristan; William, Olson

    2012-01-01

    NASA's Energy and Water Cycle Study (NEWS) program fosters collaborative research towards improved quantification and prediction of water and energy cycle consequences of climate change. In order to measure change, it is first necessary to describe current conditions. The goal of the first phase of the NEWS Water and Energy Cycle Climatology project was to develop "state of the global water cycle" and "state of the global energy cycle" assessments based on data from modern ground and space based observing systems and data integrating models. The project was a multi-institutional collaboration with more than 20 active contributors. This presentation will describe the results of the water cycle component of the first phase of the project, which include seasonal (monthly) climatologies of water fluxes over land, ocean, and atmosphere at continental and ocean basin scales. The requirement of closure of the water budget (i.e., mass conservation) at various scales was exploited to constrain the flux estimates via an optimization approach that will also be described. Further, error assessments were included with the input datasets, and we examine these in relation to inferred uncertainty in the optimized flux estimates in order to gauge our current ability to close the water budget within an expected uncertainty range.

  18. Fuel cycles using adulterated plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Brooksbank, R. E.; Bigelow, J. E.; Campbell, D. O.; Kitts, F. G.; Lindauer, R. B.

    1978-01-01

    Adjustments in the U-Pu fuel cycle necessitated by decisions made to improve the nonproliferation objectives of the US are examined. The uranium-based fuel cycle, using bred plutonium to provide the fissile enrichment, is the fuel system with the highest degree of commercial development at the present time. However, because purified plutonium can be used in weapons, this fuel cycle is potentially vulnerable to diversion of that plutonium. It does appear that there are technologically sound ways in which the plutonium might be adulterated by admixture with /sup 238/U and/or radioisotopes, and maintained in that state throughout the fuel cycle, so that the likelihood of a successful diversion is small. Adulteration of the plutonium in this manner would have relatively little effect on the operations of existing or planned reactors. Studies now in progress should show within a year or two whether the less expensive coprocessing scheme would provide adequate protection (coupled perhaps with elaborate conventional safeguards procedures) or if the more expensive spiked fuel cycle is needed as in the proposed civex pocess. If the latter is the case, it will be further necessary to determine the optimum spiking level, which could vary as much as a factor of a billion. A very basic question hangs on these determinations: What is to be the nature of the recycle fuel fabrication facilities. If the hot, fully remote fuel fabrication is required, then a great deal of further development work will be required to make the full cycle fully commercial.

  19. Optimization of the fuel cycle

    International Nuclear Information System (INIS)

    The nuclear fuel cycle can be optimized subject to a wide range of criteria. Prime amongst these are economics, sustainability of resources, environmental aspects, and proliferation-resistance of the fuel cycle. Other specific national objectives will also be important. These criteria, and their relative importance, will vary from country to country, and with time. There is no single fuel cycle strategy that is optimal for all countries. Within the short term, the industry is attached to dominant thermal reactor technologies, which themselves have two main variants, a cycle closed by reprocessing of spent fuel and subsequent recycling and a once through one where spent fuel is stored in advance of geological disposal. However, even with current technologies, much can be done to optimize the fuel cycles to meet the relevant criteria. In the long term, resource sustainability can be assured for centuries through the use of fast breeder reactors, supporting high-conversion thermal reactors, possibly also utilizing the thorium cycle. These must, however, meet the other key criteria by being both economic and safe. (author)

  20. A biogeochemical cycle for aluminium?

    Science.gov (United States)

    Exley, Christopher

    2003-09-15

    The elaboration of biogeochemical cycles for elements which are known to be essential for life has enabled a broad appreciation of the homeostatic mechanisms which underlie element essentiality. In particular they can be used effectively to identify any part played by human activities in element cycling and to predict how such activities might impact upon the lithospheric and biospheric availability of an element in the future. The same criteria were the driving force behind the construction of a biogeochemical cycle for aluminium, a non-essential element which is a known ecotoxicant and a suspected health risk in humans. The purpose of this exercise was to examine the concept of a biogeochemical cycle for aluminium and not to review the biogeochemistry of this element. The cycle as presented is rudimentary and qualitative though, even in this nascent form, it is informative and predictive and, for these reasons alone, it is deserving of future quantification. A fully fledged biogeochemical cycle for aluminium should explain the biospheric abundance of this element and whether we should expect its (continued) active involvement in biochemical evolution.

  1. The Water Cycle Solutions Network

    Science.gov (United States)

    Houser, P.; Belvedere, D.; Imam, B.; Schiffer, R.; Schlosser, C.; Gupta, H.; Welty, C.; Vörösmarty, C.; Matthews, D.; Lawford, R.

    2006-12-01

    The goal of the Water cycle Solutions Network is to improve and optimize the sustained ability of water cycle researchers, stakeholders, organizations and networks to interact, identify, harness, and extend research results to augment decision support tools and meet national needs. WaterNet will engage relevant NASA water cycle research resources and community-of-practice organizations, to develop what we term an "actionable database" that can be used to communicate and connect water cycle research results (WCRs) towards the improvement of water-related Decision Support Tools (DSTs). An actionable database includes enough sufficient knowledge about its nodes and their heritage so that connections between these nodes are identifiable and robust. Recognizing the many existing highly valuable water-related science and application networks, we will focus the balance of our efforts on enabling their interoperability in a solutions network context. We will initially focus on identification, collection, and analysis of the two end points, these being the WCRs and water related DSTs. We will then develop strategies to connect these two end points via innovative communication strategies, improved user access to NASA resources, improved water cycle research community appreciation for DST requirements, improved policymaker, management and stakeholder knowledge of NASA research and application products, and improved identification of pathways for progress. Finally, we will develop relevant benchmarking and metrics, to understand the network's characteristics, to optimize its performance, and to establish sustainability. The WaterNet will deliver numerous pre-evaluation reports that will identify the pathways for improving the collective ability of the water cycle community to routinely harness WCRs that address crosscutting water cycle challenges.

  2. Focused training boosts revenue cycle skills, accountability.

    Science.gov (United States)

    Richmond, Craig

    2011-09-01

    In 2009, the MetroHealth System took its first steps toward creating a comprehensive revenue cycle university, with the goal of developing revenue cycle staff talent and achieving best-in-class revenue cycle operations. MetroHealth became a beta site for HFMA's online Credentialed Revenue Cycle Representative (CRCR) program, and asked its revenue cycle leaders to present classes on key revenue cycle issues. As of June 2011, 62 percent of 122 revenue cycle employees who had taken the CRCR course passed the exam. The CRCR designation is now a prerequisite for career advancement in certain revenue cycle areas at MetroHealth.

  3. Antifreeze life cycle assessment (LCA

    Directory of Open Access Journals (Sweden)

    Kesić Jelena

    2005-01-01

    Full Text Available Antifreeze based on ethylene glycol is a commonly used commercial product The classification of ethylene glycol as a toxic material increased the disposal costs for used antifreeze and life cycle assessment became a necessity. Life Cycle Assessment (LCA considers the identification and quantification of raw materials and energy inputs and waste outputs during the whole life cycle of the analyzed product. The objectives of LCA are the evaluation of impacts on the environment and improvements of processes in order to reduce and/or eliminate waste. LCA is conducted through a mathematical model derived from mass and energy balances of all the processes included in the life cycle. In all energy processes the part of energy that can be transformed into some other kind of energy is called exergy. The concept of exergy considers the quality of different types of energy and the quality of different materials. It is also a connection between energy and mass transformations. The whole life cycle can be described by the value of the total loss of exergy. The physical meaning of this value is the loss of material and energy that can be used. The results of LCA are very useful for the analyzed products and processes and for the determined conditions under which the analysis was conducted. The results of this study indicate that recycling is the most satisfactory solution for the treatment of used antifreeze regarding material and energy consumption but the re-use of antifreeze should not be neglected as a solution.

  4. Air bottoming cycle, an alternative to combined cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaikko, J. [Royal Inst. of Techn., Stockholm (Sweden). Dept. of Energy Technology

    2001-10-01

    In this work, the idea of Air Bottoming Cycle (ABC) has been studied. The objectives for the work have been to establish an understanding of the concept for power and heat generation as well as to find - if possible - feasible concepts for future use in the Swedish energy system. Combined cycle in power generation is an established technology. In the conventional combined cycle, a gas turbine works as a topping cycle together with the steam (Rankine) bottoming cycle. In the ABC the steam bottoming cycle is replaced with a gas turbine (Brayton) bottoming cycle having air as a working fluid. The two gas turbines are thermally connected over a gas-to-gas heat exchanger. This concept promises savings in weight and cost, as well as operating benefits, compared to the Rankine bottoming technology. The ABC has been modelled using a heat balance program, and a parametric study for the concept optimisation as well as for off-design analysis has been performed. Performance of the ABC has been compared to other, established technologies. A preliminary economic evaluation has been made. As a result of the study, it is clarified that the Rankine bottoming cycle with steam remains superior to the ABC as regards electrical efficiency in the medium and large power scale. For small-scale applications (<10 MW{sub e}) where the thermodynamic advantage of the Rankine cycle is not dominating any longer and its economy is burdened by the heavy investment structure, the ABC becomes the better alternative for energy utilisation. A preliminary economic evaluation shows that (at energy prices autumn 2000) the ABC is at the same level as the comparable small-scale cogeneration installations. Due to high power-to-heat ratio however, higher electricity prices will favour the ABC. One interesting feature of the ABC is that about 50% of the dissipated low-value heat from the cycle is carried by clean (sterile) air at the temperature around 200 deg C. This air can be utilised for space heating or

  5. Air bottoming cycle, an alternative to combined cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaikko, J. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

    2002-02-01

    In this work, the idea of Air Bottoming Cycle (ABC) has been studied. The objectives for the work have been to establish an understanding of the concept for power and heat generation as well as to find - if possible - feasible concepts for future use in the Swedish energy system. Combined cycle in power generation is an established technology. In the conventional combined cycle, a gas turbine works as a topping cycle together with the steam (Rankine) bottoming cycle. In the ABC the steam bottoming cycle is replaced with a gas turbine (Brayton) bottoming cycle having air as a working fluid. The two gas turbines are thermally connected over a gas-to-gas heat exchanger. This concept promises savings in weight and cost, as well as operating benefits, compared to the Rankine bottoming technology. The ABC has been modelled using a heat balance program, and a parametric study for the concept optimisation as well as for off-design analysis has been performed. Performance of the ABC has been compared to other, established technologies. A preliminary economic evaluation has been made. As a result of the study, it is clarified that the Rankine bottoming cycle with steam remains superior to the ABC as regards electrical efficiency in the medium and large power scale. For small-scale applications (<10 MW{sub e}) where the thermodynamic advantage of the Rankine cycle is not dominating any longer and its economy is burdened by the heavy investment structure, the ABC becomes the better alternative for energy utilisation. A preliminary economic evaluation shows that (at energy prices autumn 2000) the ABC is at the same level as the comparable small-scale cogeneration installations. Due to high power-to-heat ratio however, higher electricity prices will favour the ABC. One interesting feature of the ABC is that about 50% of the dissipated low-value heat from the cycle is carried by clean (sterile) air at the temperature around 200 deg C. This air can be utilised for space heating or

  6. Proliferation resistance fuel cycle technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. S.; Ko, W. I

    1999-02-01

    The issues of dual use in nuclear technology are analysed for nuclear fuel cycle with special focus on uranium enrichment and spent fuel reprocessing which are considered as the most sensitive components in terms of vulnerability to diversion. Technical alternatives to mitigrate the vulnerability, as has been analysed in depth during the NASAP and INFCE era in the late seventies, are reviewed to characterize the DUPIC fuel cycle alternative. On the other hand, the new realities in nuclear energy including the disposition of weapon materials as a legacy of cold war are recast in an angle of nuclear proliferation resistance and safeguards with a discussion on the concept of spent fuel standard concept and its compliance with the DUPIC fuel cycle technology. (author)

  7. Corporate governance cycles during transition

    DEFF Research Database (Denmark)

    Jones, Derek C.; Mygind, Niels

    2004-01-01

    is faster in Estonia and this can be explained by the relatively fast pace of institutional change and evolution of important gov-ernance institutions, including tough bankruptcy legislation and advances in the financial system. JEL-codes: G3, J5, P2, P3 Keywords: corporate governance, life......We begin by identifying a typical governance life-cycle, defined as changes in ownership structure, and including both the identity of the major owner and ownership concentration. The cycle is marked by key events and phases including start-up, initial growth, mature growth, and possibly a crisis...... and restructuring stage or exit stage. The governance cycle for transitional countries reflects some specific characteristics -e.g. often privatization produces specific initial ownership structures, with an unusually high proportion of insider, especially, employee ownership. Subsequently pres...

  8. Measuring risky adolescent cycling behaviour.

    Science.gov (United States)

    Feenstra, Hans; Ruiter, Robert A C; Schepers, Jan; Peters, Gjalt-Jorn; Kok, Gerjo

    2011-09-01

    Adolescents are at a greater risk of being involved in traffic accidents than most other age groups, even before they start driving cars. This article aims to determine the factor structure of a self-report questionnaire measuring adolescent risky cycling behaviour, the ACBQ (Adolescent Cycling Behaviour Questionnaire). The questionnaire's structure was based on the widely used Driver Behaviour Questionnaire (DBQ). A sample of secondary school students (N = 1749; age range: 13-18 years) filled out the questionnaire. Factor analysis revealed a three-factor structure underlying the questionnaire, which was confirmed on two equally large portions of the entire sample. These three underlying factors were identified as errors, common violations and exceptional violations. The ACBQ is a useful instrument for measuring adolescents' risky cycling behaviour.

  9. Proliferation resistance fuel cycle technology

    International Nuclear Information System (INIS)

    The issues of dual use in nuclear technology are analysed for nuclear fuel cycle with special focus on uranium enrichment and spent fuel reprocessing which are considered as the most sensitive components in terms of vulnerability to diversion. Technical alternatives to mitigrate the vulnerability, as has been analysed in depth during the NASAP and INFCE era in the late seventies, are reviewed to characterize the DUPIC fuel cycle alternative. On the other hand, the new realities in nuclear energy including the disposition of weapon materials as a legacy of cold war are recast in an angle of nuclear proliferation resistance and safeguards with a discussion on the concept of spent fuel standard concept and its compliance with the DUPIC fuel cycle technology. (author)

  10. Optimization of data life cycles

    Science.gov (United States)

    Jung, C.; Gasthuber, M.; Giesler, A.; Hardt, M.; Meyer, J.; Rigoll, F.; Schwarz, K.; Stotzka, R.; Streit, A.

    2014-06-01

    Data play a central role in most fields of science. In recent years, the amount of data from experiment, observation, and simulation has increased rapidly and data complexity has grown. Also, communities and shared storage have become geographically more distributed. Therefore, methods and techniques applied to scientific data need to be revised and partially be replaced, while keeping the community-specific needs in focus. The German Helmholtz Association project "Large Scale Data Management and Analysis" (LSDMA) aims to maximize the efficiency of data life cycles in different research areas, ranging from high energy physics to systems biology. In its five Data Life Cycle Labs (DLCLs), data experts closely collaborate with the communities in joint research and development to optimize the respective data life cycle. In addition, the Data Services Integration Team (DSIT) provides data analysis tools and services which are common to several DLCLs. This paper describes the various activities within LSDMA and focuses on the work performed in the DLCLs.

  11. ALMA Cycle 0 Publication Statistics

    CERN Document Server

    Stoehr, Felix; Meakins, Silvia; Bishop, Marsha; Uchida, Ayako; Testi, Leonardo; Iono, Daisuke; Tatematsu, Kenichi; Wootten, Al

    2016-01-01

    The scientific impact of a facility is the most important measure of its success. Monitoring and analysing the scientific return can help to modify and optimise operations and adapt to the changing needs of scientific research. The methodology that we have developed to monitor the scientific productivity of the ALMA Observatory, as well as the first results, are described. We focus on the outcome of the first cycle (Cycle 0) of ALMA Early Science operations. Despite the fact that only two years have passed since the completion of Cycle 0 and operations have already changed substantially, this analysisconfirms the effectiveness of the underlying concepts. We find that ALMA is fulfilling its promise as a transformational facility for the observation of the Universe in the submillimetre.

  12. Modeling road-cycling performance.

    Science.gov (United States)

    Olds, T S; Norton, K I; Lowe, E L; Olive, S; Reay, F; Ly, S

    1995-04-01

    This paper presents a complete set of equations for a "first principles" mathematical model of road-cycling performance, including corrections for the effect of winds, tire pressure and wheel radius, altitude, relative humidity, rotational kinetic energy, drafting, and changed drag. The relevant physiological, biophysical, and environmental variables were measured in 41 experienced cyclists completing a 26-km road time trial. The correlation between actual and predicted times was 0.89 (P road-cycling performance are maximal O2 consumption, fractional utilization of maximal O2 consumption, mechanical efficiency, and projected frontal area. The model is then applied to some practical problems in road cycling: the effect of drafting, the advantage of using smaller front wheels, the effects of added mass, the importance of rotational kinetic energy, the effect of changes in drag due to changes in bicycle configuration, the normalization of performances under different conditions, and the limits of human performance.

  13. SIRTF Cycle-1 Research Opportunities

    Science.gov (United States)

    Soifer, B. T.; Bicay, M. D.

    2003-12-01

    The Space InfraRed Telescope Facility (SIRTF), the fourth and final element in NASA's family of Great Observatories, was successfully launched into an Earth-trailing heliocentric orbit on August 25, 2003. The SIRTF Science Center (SSC) at Caltech is now soliciting Cycle-1 research proposals from the worldwide scientific community. Proposals must be submitted electronically to the SSC by February 14, 2004. A preliminary version of the Cycle-1 Call for Proposals (CP) was issued by the SSC in November 2002. A CP Update and supporting technical documentation, which incorporates the on-orbit performance of the observatory, were released in December 2003. Investigations may be proposed for new SIRTF observations, through the General Observer (GO) program, or for archival research. About 3700 hours of observing time is being offered for the Cycle-1 GO Program, in small (less than 50 hours) and medium (50 to 200 hours) categories. More than \\15 million in NASA data analysis support is available to qualified GO investigators. For GO proposals, a detailed list of proposed observations, generated by the SIRTF Planning Observations Tool, must accompany the research proposal. The Archival Research (AR) Program in Cycle-1 is limited to the analysis of data from the First-Look Survey, a 100-hour program to be executed by the SSC at the start of the science mission. Up to \\750,000 in NASA data analysis support is available to qualified AR investigators. All documents supporting the Cycle-1 solicitation are available online in the Proposal Kit section of the SSC public Web site (http://sirtf.caltech.edu/SSC/). Questions pertaining to the Cycle-1 CP should be sent electronically to the SSC HelpDesk at sirtf@ipac.caltech.edu. SIRTF is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA.

  14. Tracing the glacial sulphur cycle

    Science.gov (United States)

    Hansson, M. E.; Jonsell, U.; Bigler, M.; de Angelis, M.; Fischer, H.; Siggaard-Andersen, M.-L.; Steffensen, J. P.; Udisti, R.; Wolff, E.

    2003-04-01

    Sulphate aerosols are playing a major role in climate forcing in the present atmosphere and therefore possibly also during other climatic stages. The deposition of sulphur-containing species onto polar ice sheets provides a tool for determining variations in the sulphur cycle in the past. Relatively short atmospheric residence times for sulphate aerosols cause spatial gradients and a high sensitivity to variations in the general circulation of the atmosphere and the hydrological cycle. Several factors may influence the air-snow transfer functions and post-depositional process may modify the deposited signal. Therefore, both a large spatial and temporal coverage is needed to identify significant changes in the sulphur cycle in the past. The EPICA Dome C ice core from Antarctica is providing the longest records ever, spanning several glacial cycles. Unique high-resolution chemical records, from discontinuous samples analysed by Ion Chromatography (IC), are gradually evolving from the cooperation between the laboratories in the EPICA Chemistry Consortium. The EPICA DML ice core is analysed in parallel by the same laboratories and the profiles are growing with the progress of the drilling each season. The sulphate and methane sulphonate records are here in focus and will be presented as far as they reach at present. High-resolution chemical records are now also available from the NorthGRIP ice core from Greenland spanning the last glacial cycle. An interhemispheric comparison of sulphur-containing species during the glacial period will be presented, using both new high-resolution data and previous ice core data from a few locations as well as initial results from sulphur isotope measurements, with the aim to increase our understanding of variations in the global sulphur cycle with climate change.

  15. Tricarboxylic-acid-cycle intermediates and cycle endurance capacity.

    Science.gov (United States)

    Brown, Amy C; Macrae, Holden S H; Turner, Nathan S

    2004-12-01

    The purpose of this study was to determine whether ingestion of a multinutrient supplement containing 3 tricarboxylic-acid-cycle intermediates (TCAIs; pyridoxine-alpha-ketoglutarate, malate, and succinate) and other substances potentially supporting the TCA cycle (such as aspartate and glutamate) would improve cyclists' time to exhaustion during a submaximal endurance-exercise test (approximately 70 % to 75 % VO2peak) and rate of recovery. Seven well-trained male cyclists (VO2max 67.4 2.1 mL x kg(-1) x in(-1), 28.6 +/- 2.4 y) participated in a randomized, double-blind crossover study for 7 wk. Each took either the treatment or a placebo 30 min before and after their normal training sessions for 3 wk and before submaximal exercise tests. There were no significant differences between the TCAI group (KI) and placebo group (P) in time to exhaustion during cycling (KI = 105 +/- 18, P = 113 +/- 11 min); respiratory-exchange ratio at 20-min intervals; blood lactate and plasma glucose before, after, and at 30-min intervals during exercise; perceived exertion at 20-min intervals during exercise; or time to fatigue after the 30-min recovery (KI = 16.1 +/- 3.2, P = 15 +/- 2 min). Taking a dietary sport supplement containing several TCAIs and supporting substances for 3 wk does not improve cycling performance at 75 % VO2peak or speed recovery from previously fatiguing exercise.

  16. Optimal Life Cycle Portfolio Choice with Housing Market Cycles

    DEFF Research Database (Denmark)

    Fischer, Marcel; Stamos, Michael Z.

    2013-01-01

    income, and pre-existing housing wealth but also the state of the housing market significantly affect household decisions. Consistently with the data, the model predicts that in good states of housing market cycles (1) homeownership rates increase, (2) households buying homes invest a larger share...

  17. Simple ocean carbon cycle models

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira, K. [Lawrence Livermore National Lab., CA (United States); Hoffert, M.I. [New York Univ., NY (United States). Dept. of Earth System Sciences; Siegenthaler, U. [Bern Univ. (Switzerland). Inst. fuer Physik

    1994-02-01

    Simple ocean carbon cycle models can be used to calculate the rate at which the oceans are likely to absorb CO{sub 2} from the atmosphere. For problems involving steady-state ocean circulation, well calibrated ocean models produce results that are very similar to results obtained using general circulation models. Hence, simple ocean carbon cycle models may be appropriate for use in studies in which the time or expense of running large scale general circulation models would be prohibitive. Simple ocean models have the advantage of being based on a small number of explicit assumptions. The simplicity of these ocean models facilitates the understanding of model results.

  18. SNMR pulse sequence phase cycling

    Science.gov (United States)

    Walsh, David O; Grunewald, Elliot D

    2013-11-12

    Technologies applicable to SNMR pulse sequence phase cycling are disclosed, including SNMR acquisition apparatus and methods, SNMR processing apparatus and methods, and combinations thereof. SNMR acquisition may include transmitting two or more SNMR pulse sequences and applying a phase shift to a pulse in at least one of the pulse sequences, according to any of a variety cycling techniques. SNMR processing may include combining SNMR from a plurality of pulse sequences comprising pulses of different phases, so that desired signals are preserved and indesired signals are canceled.

  19. Ramsey Results for Cycle Spectra

    DEFF Research Database (Denmark)

    Brandt, S.; Joos, F.; Muttel, J.;

    2013-01-01

    Let C(G) denote the set of lengths of cycles of a graph G of order n and let (G) over bar denote the complement of G. We show that if n >= 6, then C(G) boolean OR C((G) over bar) contains all odd l with 3......Let C(G) denote the set of lengths of cycles of a graph G of order n and let (G) over bar denote the complement of G. We show that if n >= 6, then C(G) boolean OR C((G) over bar) contains all odd l with 3...

  20. Business Cycles in Developing Countries

    DEFF Research Database (Denmark)

    Rand, John; Tarp, Finn

    2002-01-01

    This paper demonstrates that developing countries differ considerably from their developed counterparts when focus is on the nature and characteristics of short run macroeconomic fluctuations. Cycles are generally shorter, and the stylized facts of business cycles across countries are more diverse...... than those of the rather uniform industrialized countries. Supply-side models are generally superior in explaining changes in output, but a “one-size fits all” approach in formulating policy is inappropriate. Our results also illustrate the critical importance of understanding business regularities...... as a stepping-stone in the process of designing appropriate stabilization policy and macroeconomic management in developing countries....

  1. Life cycle of remanufactured engines

    Institute of Scientific and Technical Information of China (English)

    YANG Ming; CHEN Ming

    2005-01-01

    The life cycle index of remanufactured engines was assessed by using the method of life cycle assessment (LCA). A remanufactured engine of a certain domestic brand was taken as researching object. Engine reproducing engineering was investigated from three aspects which were energy, material and environment. The application of LCA on remanufacturing engines was discussed in detail with a practical case. The results indicate that remanufackg CO2 , 6.09 kg CO, 1.01 kg NOx, 3. 985 kg SOx and 288. 725 kg solid waste. The remanufacturing of engines possesses great economic value and practicability.

  2. Digital calculations of engine cycles

    CERN Document Server

    Starkman, E S; Taylor, C Fayette

    1964-01-01

    Digital Calculations of Engine Cycles is a collection of seven papers which were presented before technical meetings of the Society of Automotive Engineers during 1962 and 1963. The papers cover the spectrum of the subject of engine cycle events, ranging from an examination of composition and properties of the working fluid to simulation of the pressure-time events in the combustion chamber. The volume has been organized to present the material in a logical sequence. The first two chapters are concerned with the equilibrium states of the working fluid. These include the concentrations of var

  3. Biogeochemical cycling and remote sensing

    Science.gov (United States)

    Peterson, D. L.

    1985-01-01

    Research is underway at the NASA Ames Research Center that is concerned with aspects of the nitrogen cycle in terrestrial ecosystems. An interdisciplinary research group is attempting to correlate nitrogen transformations, processes, and productivity with variables that can be remotely sensed. Recent NASA and other publications concerning biogeochemical cycling at global scales identify attributes of vegetation that could be related or explain the spatial variation in biologically functional variables. These functional variables include net primary productivity, annual nitrogen mineralization, and possibly the emission rate of nitrous oxide from soils.

  4. Properties of stellar activity cycles

    CERN Document Server

    Korhonen, Heidi

    2015-01-01

    The current photometric datasets, that span decades, allow for studying long-term cycles on active stars. Complementary Ca H&K observations give information also on the cycles of normal solar-like stars, which have significantly smaller, and less easily detectable, spots. In the recent years, high precision space-based observations, for example from the Kepler satellite, have allowed also to study the sunspot-like spot sizes in other stars. Here I review what is known about the properties of the cyclic stellar activity in other stars than our Sun.

  5. Properties of stellar activity cycles

    OpenAIRE

    Korhonen, Heidi

    2015-01-01

    The current photometric datasets, that span decades, allow for studying long-term cycles on active stars. Complementary Ca H&K observations give information also on the cycles of normal solar-like stars, which have significantly smaller, and less easily detectable, spots. In the recent years, high precision space-based observations, for example from the Kepler satellite, have allowed also to study the sunspot-like spot sizes in other stars. Here I review what is known about the properties of ...

  6. A short note on Reitlinger thermodynamic cycles

    CERN Document Server

    Sparavigna, Amelia Carolina

    2015-01-01

    It is well known that Carnot cycle is the thermodynamic cycle which has the best thermal efficiency. However, an entire class of cycles exists that can have the same maximum efficiency: this class is that of the regenerative Reitlinger cycles. Here we discuss them.

  7. Fundamental Cycles of Cognitive Growth.

    Science.gov (United States)

    Pegg, John

    Over recent years, various theories have arisen to explain and predict cognitive development in mathematics education. We focus on an underlying theme that recurs throughout such theories: a fundamental cycle of growth in the learning of specific concepts, which we frame within broader global theories of individual cognitive growth. Our purpose is…

  8. The product life cycle revisited

    DEFF Research Database (Denmark)

    Ulhøi, John Parm

    1995-01-01

    Efter et introduktionsafsnit følger afsnit II, hvor der gives en historisk analyse af Life Cycle Assessment (LCA) og Environmental Impact Assessment (EIA). I afsnit III munder analysen ud i en vurdering af ligheder og forskelle mellem LCA analyser og EIA analyser, og en diskussion følger af...

  9. Business Cycle Dependent Unemployment Insurance

    DEFF Research Database (Denmark)

    Andersen, Torben M.; Svarer, Michael

    The consequences of business cycle contingencies in unemployment insurance systems are considered in a search-matching model allowing for shifts between "good" and "bad" states of nature. We show that not only is there an insurance argument for such contingencies, but there may also be an incentive...

  10. Digital daily cycles of individuals

    DEFF Research Database (Denmark)

    Aledavood, Talayeh; Jørgensen, Sune Lehmann; Saramäki, Jari

    2015-01-01

    day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We...

  11. Nuclear fuel cycle. V. 2

    International Nuclear Information System (INIS)

    Nuclear fuel cycle information in some countries that develop, supply or use nuclear energy is presented. Data about Argentina, Australia, Belgium, Netherlands, Italy, Denmarmark, Norway, Sweden, Switzerland, Finland, Spain and India are included. The information is presented in a tree-like graphic way. (C.S.A.)

  12. Cycles and events in stratigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Einsele, G.; Ricken, W.; Seilacher, A. (eds.)

    1991-01-01

    This book reviews and discusses the most up-to-date knowledge in the fields of cyclostratigraphy and event stratigraphy. The book contains 48 papers contributed by the most knowledgeable geologists and paleontologists in the fields of cycle and event stratigraphy. It is divided into two parts. Part one is concerned with the structure of individual beds and larger cycles and sequences and discusses; rhythmic stratification, event stratification, diagenetic overprint, cherts and phosphorites, and preservation and biologic destruction of laminated sediments. Part two, on larger cycles and sequences, looks at sequences, hierarchies, causes and environmental expression, and timing and correlation, i.e. the cycles of frequencies from millions of years to thousands of years (Milankovich band). Summaries on spectral analysis are also presented. There are 80 pages of references and a comprehensive index. It is extensively illustrated with line drawings and graphs. Practicing sedimentary geologists without access to a good library or find it hard to keep up with the plethora of journal articles and want a refresher in this area of stratigraphy will find the book particularly useful.

  13. Nuclear fuel cycle. V. 1

    International Nuclear Information System (INIS)

    Nuclear fuel cycle information in the main countries that develop, supply or use nuclear energy is presented. Data about Japan, FRG, United Kingdom, France and Canada are included. The information is presented in a tree-like graphic way. (C.S.A.)

  14. Sorption Refrigeration / Heat Pump Cycles

    Science.gov (United States)

    Saha, Bidyut Baran; Alam, K. C. Amanul; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    Over the past few decades there have been considerable efforts to use adsorption (solid/vapor) for cooling and heat pump applications, but intensified efforts were initiated only since the imposition of international restrictions on the production and use of CFCs (chlorofluorocarbons) and HCFCs (hydrochlorofluorocarbons). Up to now, only the desiccant evaporative cooling system of the open type has achieved commercial use, predominantly in the United States. Closed-type adsorption refrigeration and heat pump systems are rarely seen in the market, or are still in the laboratory testing stage. Promising recent development have been made in Japan for the use of porous metal hydrides and composite adsorbents. In this paper, a short description of adsorption theories along with an overview of present status and future development trends of thermally powered adsorption refrigeration cycles are outlined putting emphasis on experimental achievements. This paper also addressed some advanced absorption cycles having relatively higher COP, and also summarizes fundamental concepts of GAX cycles and various GAX cycles developed for heat pump applications.

  15. H gas turbine combined cycle

    Energy Technology Data Exchange (ETDEWEB)

    Corman, J. [General Electric Co., Schenectady, NY (United States)

    1995-10-01

    A major step has been taken in the development of the Next Power Generation System - {open_quotes}H{close_quotes} Technology Combined Cycle. This new gas turbine combined-cycle system increases thermal performance to the 60% level by increasing gas turbine operating temperature to 1430 C (2600 F) at a pressure ratio of 23 to 1. Although this represents a significant increase in operating temperature for the gas turbine, the potential for single digit NOx levels (based upon 15% O{sub 2}, in the exhaust) has been retained. The combined effect of performance increase and environmental control is achieved by an innovative closed loop steam cooling system which tightly integrates the gas turbine and steam turbine cycles. The {open_quotes}H{close_quotes} Gas Turbine Combined Cycle System meets the goals and objectives of the DOE Advanced Turbine System Program. The development and demonstration of this new system is being carried out as part of the Industrial/Government cooperative agreement under the ATS Program. This program will achieve first commercial operation of this new system before the end of the century.

  16. Multilevel cycle of anthropogenic copper.

    Science.gov (United States)

    Graedel, T E; van Beers, D; Bertram, M; Fuse, K; Gordon, R B; Gritsinin, A; Kapur, A; Klee, R J; Lifset, R J; Memon, L; Rechberger, H; Spatari, S; Vexler, D

    2004-02-15

    A comprehensive contemporary cycle for stocks and flows of copper is characterized and presented, incorporating information on extraction, processing, fabrication and manufacturing, use, discard, recycling, final disposal, and dissipation. The analysis is performed on an annual basis, ca. 1994, at three discrete governmental unit levels--56 countries or country groups that together comprise essentially all global anthropogenic copper stocks and flows, nine world regions, and the planet as a whole. Cycles for all of these are presented and discussed, and a "best estimate" global copper cycle is constructed to resolve aggregation discrepancies. Among the most interesting results are (1) transformation rates and recycling rates in apparently similar national economies differ by factors of two or more (country level); (2) the discard flows that have the greatest potential for copper recycling are those with low magnitude flows but high copper concentrations--electronics, electrical equipment, and vehicles (regional level); (3) worldwide, about 53% of the copper that was discarded in various forms was recovered and reused or recycled (global level); (4) the highest rate of transfer of discarded copper to repositories is into landfills, but the annual amount of copper deposited in mine tailings is nearly as high (global level); and (5) nearly 30% of copper mining occurred merely to replace copper that was discarded. The results provide a framework for similar studies of other anthropogenic resource cycles as well as a basis for supplementary studies in resource stocks, industrial resource utilization, waste management, industrial economics, and environmental impacts. PMID:14998044

  17. Activity cycles of M dwarfs

    Science.gov (United States)

    Savanov, I. S.

    2012-09-01

    We have determined activity cycles for coolest M dwarfs using photometry from the ASAS survey. The time scales of brightness variations were determined for the program stars using calculated amplitude power spectra and wavelet spectra. Most of ther program stars display periodicities in their light-curve variations, with periods from hundreds of days to years. Analysis of diagrams plotting P cyc/ P rot versus 1/ P rot in logarithmic coordinates shows that the data for all our program objects fit the general relation quite well. No differences in the activity cycles are found for our sample stars, which have different masses and thus internal structures, some having convective envelopes and others being totally convective. Our analysis indicates that the slope i of this relation is close to unity, regardless of whether it is determined from all data, from data for the shortest cycles, or from data for the longest cycles. This value of i differs from values in the literature for stars of other spectral types. Our analysis of the P cyc- P rot relation indicates that the activity cycles for the studied sample of M dwarfs do not depend on the rotation periods of these objects. The data for the studied objects do not agree with any of the relations for relatively young (active) stars or older (less active) stars. The studied M dwarfs probably form another branch of low-mass stars that display more random, irregular magnetic activity on their surfaces, which is generated and supported by the distributed dynamo mechanism or a small-scale dynamo mechanism.

  18. The economics of thorium fuel cycles

    International Nuclear Information System (INIS)

    The individual cost components and the total fuel cycle costs for natural uranium and thorium fuel cycles are discussed. The thorium cycles are initiated by using either enriched uranium or plutonium. Subsequent thorium cycles utilize recycled uranium-233 and, where necessary, either uranium-235 or plutonium as topping. A calculation is performed to establish the economic conditions under which thorium cycles are economically attractive. (auth)

  19. When Product Life Cycle Meets Customer Activity Cycle

    DEFF Research Database (Denmark)

    Tan, Adrian Ronald

    2007-01-01

    Manufacturing companies have traditionally focused their efforts on designing, developing and producing products to offer on the market. Today global competition and demands for greater company responsibility of products throughout their entire life cycle are driving manufacturing companies...... to shift market strategies from a transactional approach to an approach based on the establishment and management of customer relationships (Grönroos, 1999). A growing number of studies and research programmes have focused on the potentials of business strategies based on providing the value of utility...... of products throughout their life cycle by designing integrated solutions of products and services. This approach has been dubbed ‘product/service-systems (PSS)’ (Mont, 2004). Although relationship marketing and product/service-system design have their roots in each their own research fields - marketing...

  20. Nitrogen cycling. Rapid nitrous oxide cycling in the suboxic ocean.

    Science.gov (United States)

    Babbin, Andrew R; Bianchi, Daniele; Jayakumar, Amal; Ward, Bess B

    2015-06-01

    Nitrous oxide (N2O) is a powerful greenhouse gas and a major cause of stratospheric ozone depletion, yet its sources and sinks remain poorly quantified in the oceans. We used isotope tracers to directly measure N2O reduction rates in the eastern tropical North Pacific. Because of incomplete denitrification, N2O cycling rates are an order of magnitude higher than predicted by current models in suboxic regions, and the spatial distribution suggests strong dependence on both organic carbon and dissolved oxygen concentrations. Furthermore, N2O turnover is 20 times higher than the net atmospheric efflux. The rapid rate of this cycling coupled to an expected expansion of suboxic ocean waters implies future increases in N2O emissions. PMID:26045434

  1. 2007-2011年四川省阿坝州综合措施预防儿童大骨节病效果分析%Effects of comprehensive measures on prevention of children's Kashin-Beck disease in Aba state Sichuan province from 2007 to 2011

    Institute of Scientific and Technical Information of China (English)

    黄慧; 邓佳云; 李富忠; 李津蜀; 秦胜超; 陈开华; 王丽华

    2012-01-01

    Objective To observe the effects of comprehensive measures of changing grain,selenium supplementation,off-site education and resettlement on prevention of children's Kashin-Beck disease in Aba state.Methods Fifty eight villages in Aba Kashin-Beck disease areas were chosen as intervention points in Aba state Sichuan province from 2007 to 2011.Based on the implementation of prevention and control measures,the villages were divided into off-site education + changing grain + selenium supplementation group and resettlement + off-site education + changing grain + selenium supplementation group,Geletuo town of Seda county,Ganzi state was selected as a control point,and right-hand anteroposterior X-ray examination(including the wrist) was carried out on children aged 6-13 from 2007 to 2011 annually.Clinical and X-ray diagnosis of Kashin-Beck disease was made in accordance with "the Diagnostic Criteria of Kaschin-Beck Disease"(GB 16003-1995).The effects of prevention and control measures were evaluated by comparing the child X-ray detection rate before and after the implementation of the measures.Results The average X-ray positive detectable rate of children in the intervention points was 2.07%(66/3181),2.72% (69/2540),1.16% (35/3017),0.56% (19/3397) and 0.56% (24/4273),respectively from 2007 to 2011,with a downward trend (x2trend =66.74,P < 0.01).There was a downward trend in the average X-ray positive detectable rate of children in off-site education + changing grain + selenium supplementation group [1.60%(29/1809),2.63% (39/1484),1.29% (25/1941),0.64% (15/2332),0.42% (10/2379)] and resettlement + off-site education + changing grain + selenium supplementation group [2.70% (37/1372),2.84% (30/1056),0.93%(10/1076),0.38% (4/1065),0.74%(14/1894)] (x2trend=30.97,35.19,all P < 0.01).The average X-ray positive detectable rate of children in the intervention group was 0 from 2007 to 2010,and was 1.61% (1/62) in 2011.The difference of X

  2. When Product Life Cycle Meets Customer Activity Cycle

    OpenAIRE

    Tan, Adrian Ronald

    2007-01-01

    Manufacturing companies have traditionally focused their efforts on designing, developing and producing products to offer on the market. Today global competition and demands for greater company responsibility of products throughout their entire life cycle are driving manufacturing companies to shift market strategies from a transactional approach to an approach based on the establishment and management of customer relationships (Grönroos, 1999). A growing number of studies and research progra...

  3. VISION - Verifiable Fuel Cycle Simulation of Nuclear Fuel Cycle Dynamics

    International Nuclear Information System (INIS)

    The U.S. DOE Advanced Fuel Cycle Initiative's (AFCI) fundamental objective is to provide technology options that--if implemented--would enable long-term growth of nuclear power while improving sustainability and energy security. The AFCI organization structure consists of four areas; Systems Analysis, Fuels, Separations and Transmutations. The Systems Analysis Working Group is tasked with bridging the program technical areas and providing the models, tools, and analyses required to assess the feasibility of design and deployment options and inform key decision makers. An integral part of the Systems Analysis tool set is the development of a system level model that can be used to examine the implications of the different mixes of reactors, implications of fuel reprocessing, impact of deployment technologies, as well as potential ''exit'' or ''off ramp'' approaches to phase out technologies, waste management issues and long-term repository needs. The Verifiable Fuel Cycle Simulation Model (VISION) is a computer-based simulation model that allows performing dynamic simulations of fuel cycles to quantify infrastructure requirements and identify key trade-offs between alternatives. It is based on the current AFCI system analysis tool ''DYMOND-US'' functionalities in addition to economics, isotopic decay, and other new functionalities. VISION is intended to serve as a broad systems analysis and study tool applicable to work conducted as part of the AFCI and Generation IV reactor development studies

  4. ITER-FEAT fuel cycle

    International Nuclear Information System (INIS)

    The Fuel Cycle, which includes plasma fuelling and exhaust, as well as exhaust processing and isotope separation, is one of the key elements on which the successful operation of ITER will depend. This paper provides an overview of this system, reviewing requirements, operational scenarios, and the integration of the various subsystems using the ITER fuel cycle dynamic simulation program CFTSIM. The requirements to provide a plasma fuelling rate of 200 Pam3s-1, with a flat-top burn of ∼400s and a repetition rate of two pulses per hour have the greatest influence on the design. However, while a flat-top burn of ∼400s is the initial design basis, the capability to extend the pulse to 3,000s in the longer term is essential from an operational perspective. (author)

  5. Soleus stretch reflex during cycling

    DEFF Research Database (Denmark)

    Grey, Michael James; Pierce, C. W.; Milner, T. E.;

    2001-01-01

    The modulation and strength of the human soleus short latency stretch reflex was investigated by mechanically perturbing the ankle during an unconstrained pedaling task. Eight subjects pedaled at 60 rpm against a preload of 10 Nm. A torque pulse was applied to the crank at various positions during...... the crank cycle, producing ankle dorsiflexion perturbations of similar trajectory. The stretch reflex was greatest during the power phase of the crank cycle and was decreased to the level of background EMG during recovery. Matched perturbations were induced under static conditions at the same crank angle...... and background soleus EMG as recorded during the power phase of active pedaling. The magnitude of the stretch reflex was not statistically different from that during the static condition throughout the power phase of the movement. The results of this study indicate that the stretch reflex is not depressed during...

  6. THE CANADIAN POLITICAL BUSINESS CYCLE

    Directory of Open Access Journals (Sweden)

    Barbara Libby

    2000-01-01

    Full Text Available This paper will discuss the existence of a Canadian Political Business Cycle (PBC during the period 1946-1989. Logit analysis was used to determine if changes in the unemployment rate, growth of real GNE and the rate of inflation are significantly different in the period before an election than during the rest of the electoral term. It was found that the rate of growth in the unemployment rate declines and the rate of growth of real GNP increases in the four quarters before an election. The behavior of these variables reverses in the period after an election. These findings are consistent with a political business cycle. Policy variables, under a majority government, also behave in a manner associated with a PBC, with the government stimulating the economy approximately two years into its term so that good economic news will occur before it has to call an election. Minority governments tend to simulate the economy immediately after taking office.

  7. Breaking the cycle of abuse.

    Science.gov (United States)

    Egeland, B; Jacobvitz, D; Sroufe, L A

    1988-08-01

    The aim of this study was to identify variables that distinguish mothers who broke the cycle of abuse from mothers who were abused as children and who also abused their own children. Based on maternal interviews and questionnaires completed over a 64-month period, measures of mothers' past and current relationship experiences, stressful life events, and personality characteristics were obtained. Abused mothers who were able to break the abusive cycle were significantly more likely to have received emotional support from a nonabusive adult during childhood, participated in therapy during any period of their lives, and to have had a nonabusive and more stable, emotionally supportive, and satisfying relationship with a mate. Abused mothers who reenacted their maltreatment with their own children experienced significantly more life stress and were more anxious, dependent, immature, and depressed. PMID:3168615

  8. Swimming as a limit cycle

    CERN Document Server

    Jacobs, Henry O

    2012-01-01

    Steady swimming can be characterized as both periodic and stable. These characteristics are the very definition of limit cycles, and so we ask "Can we view swimming as a limit cycle?" In this paper we will find that the answer is "yes". We will define a class of dissipative systems which correspond to the passive dynamics of a body immersed in a Navier-Stokes fluid (i.e. the dynamics of a dead fish). Upon performing reduction by symmetry we will find a hyperbolically stable fixed point which corresponds to the stability of a dead fish in stagnant water. Given a periodic force on the shape of the body we will invoke the persistence theorem to assert the existence of a loop which approximately satisfies the exact equations of motion. If we lift this loop with a phase reconstruction formula we will find that the lifted loops are not loops, but stable trajectories which represent regular periodic motion reminiscent of swimming.

  9. Carnot cycle for an oscillator

    CERN Document Server

    Arnaud, J; Philippe, F

    2002-01-01

    Carnot established in 1824 that the efficiency of cyclic engines operating between a hot bath at absolute temperature Th and a cold bath at temperature Tc cannot exceed 1-Tc/Th. This result implies the existence of an entropy function S(U) with the property that d^2S/dU^2 less equal 0, where U denotes the average energy. Linear single-mode systems alternately in contact with hot and cold baths obey these principles. A specific expression of the work done per cycle by an oscillator is derived from a prescription established by Einstein in 1906: heat baths may exchange energy with oscillators at angular frequency omega only by amounts hbar *omega, where 2*pi*hbar denotes the Planck constant. Non-reversible cycles are illustrated. The paper is essentially self-contained.

  10. Life cycle assessment of turbines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-10-15

    This report forms part of the final reporting of the project 'LCA and turbines, which has been carried out as a cooperation between Vestas Wind Systems A/S and Tech-wise A/S on behalf of Elsam A/S. The goal of the project was to create a life cycle model for a big Vestas offshore turbine. Based on the offshore model an analysis has been prepared and this analysis will show the most significant environmental impacts a turbine will be subject to during its life cycle. Furthermore we have prepared a recommendation on how an improvement strategy on a selected area can be drafted. Finally, a preliminary environmental declaration of contents will be prepared for the turbine in question and 1 kWh generated from here. (BA)

  11. Business cycle synchronization in Europe

    DEFF Research Database (Denmark)

    Bergman, Ulf Michael; Jonung, Lars

    2011-01-01

    In this paper we study business cycle synchronization in the three Scandinavian countries Denmark, Norway and Sweden prior to, during and after the Scandinavian Currency Union 1873–1913. We find that the degree of synchronization tended to increase during the currency union, thus supporting earli...... empirical evidence. Estimates of factor models suggest that common Scandinavian shocks are important for these three countries. At the same time we find evidence suggesting that the importance of these shocks does not depend on the monetary regime.......In this paper we study business cycle synchronization in the three Scandinavian countries Denmark, Norway and Sweden prior to, during and after the Scandinavian Currency Union 1873–1913. We find that the degree of synchronization tended to increase during the currency union, thus supporting earlier...

  12. Single-cycle nonlinear optics

    Energy Technology Data Exchange (ETDEWEB)

    Max-Planck-Institut fur Quantenoptik; Goulielmakis, E.; Schultze, M.; Hofstetter, M.; Yakovlev, V. S.; Gagnon, J.; Uiberacker, M.; Aquila, A. L.; gullikson, E. M.; attwood, D. T.; Kienberger, R.; Krausz, F.; Kleineberg, U.

    2008-11-05

    Nonlinear optics plays a central role in the advancement of optical science and laser-based technologies. We report on the confinement of the nonlinear interaction of light with matter to a single wave cycle and demonstrate its utility for time-resolved and strong-field science. The electric field of 3.3-femtosecond, 0.72-micron laser pulses with a controlled and measured waveform ionizes atoms near the crests of the central wave cycle, with ionization being virtually switched off outside this interval. Isolated sub-100-attosecond pulses of extreme ultraviolet light (photon energy {approx} 80 electron volts), containing {approx} 0.5 nanojoule of energy, emerge from the interaction with a conversion efficiency of {approx} 10{sup -6}. These tools enable the study of the precision control of electron motion with light fields and electron-electron interactions with a resolution approaching the atomic unit of time ({approx} 24 attoseconds).

  13. HTGR fuel and fuel cycle technology

    Energy Technology Data Exchange (ETDEWEB)

    Lotts, A.L.; Coobs, J.H.

    1976-08-01

    The status of fuel and fuel cycle technology for high-temperature gas-cooled reactors (HTGRs) is reviewed. The all-ceramic core of the HTGRs permits high temperatures compared with other reactors. Core outlet temperatures of 740/sup 0/C are now available for the steam cycle. For advanced HTGRs such as are required for direct-cycle power generation and for high-temperature process heat, coolant temperatures as high as 1000/sup 0/C may be expected. The paper discusses the variations of HTGR fuel designs that meet the performance requirements and the requirements of the isotopes to be used in the fuel cycle. Also discussed are the fuel cycle possibilities, which include the low-enrichment cycle, the Th-/sup 233/U cycle, and plutonium utilization in either cycle. The status of fuel and fuel cycle development is summarized.

  14. National Policy on Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    National policy on nuclear fuel cycle is aimed at attaining the expected condition, i.e. being able to support optimality the national energy policy and other related Government policies taking into account current domestic nuclear fuel cycle condition and the trend of international nuclear fuel cycle development, the national strength, weakness, thread and opportunity in the field of energy. This policy has to be followed by the strategy to accomplish covering the optimization of domestic efforts, cooperation with other countries, and or purchasing licences. These policy and strategy have to be broken down into various nuclear fuel cycle programmes covering basically assesment of the whole cycle, performing research and development of the whole cycle without enrichment and reprocessing being able for weapon, as well as programmes for industrialization of the fuel cycle stepwisery commencing with the middle part of the cycle and ending with the edge of the back-end of the cycle

  15. Phase lags of solar hemispheric cycles

    CERN Document Server

    Muraközy, J

    2013-01-01

    The North-South asymmetry of solar activity is variable in time and strength. We analyse the long-term variation of the phase lags of hemispheric cycles and check a conjectured relationship between these phase lags and the hemispheric cycle strengths. Sunspot data are used from cycles 12-23 in which the separation of northern and southern hemispheres is possible. The centers of mass of the hemispheric cycle profiles were used to study the phase relations and relative strengths of the hemispheric cycles. This approach considers a cycle as a whole and disregards the short-term fluctuations of the cycle time profile. The phase of the hemispheric cycles shows an alternating variation: the northern cycle leads in 4 cycles and follows in 4 cycles. No significant relationship is found between the phase and strength differences of the hemispheric cycles. The period of 4+4 cycles appears to be close to the Gleissberg cycle and may provide a key to its physical background. It may raise a new aspect in the solar dynamo ...

  16. Biomechanics of Counterweighted One-Legged Cycling.

    Science.gov (United States)

    Elmer, Steven J; McDaniel, John; Martin, James C

    2016-02-01

    One-legged cycling has served as a valuable research tool and as a training and rehabilitation modality. Biomechanics of one-legged cycling are unnatural because the individual must actively lift the leg during flexion, which can be difficult to coordinate and cause premature fatigue. We compared ankle, knee, and hip biomechanics between two-legged, one-legged, and counterweighted (11.64 kg) one-legged cycling. Ten cyclists performed two-legged (240 W), one-legged (120 W), and counterweighted one-legged (120 W) cycling (80 rpm). Pedal forces and limb kinematics were recorded to determine work during extension and flexion. During counterweighted one-legged cycling relative ankle dorsiflexion, knee flexion, and hip flexion work were less than one-legged but greater than two-legged cycling (all P one-legged cycling were greater than one-legged but less than two-legged cycling (all P one-legged cycling reduced but did not eliminate differences in joint flexion and extension actions between one- and two-legged cycling. Even with these differences, counterweighted one-legged cycling seemed to have advantages over one-legged cycling. These results, along with previous work highlighting physiological characteristics and training adaptations to counterweighted one-legged cycling, demonstrate that this exercise is a viable alternative to one-legged cycling.

  17. Branes wrapped on coassociative cycles

    International Nuclear Information System (INIS)

    We obtain a supergravity solution arising when D6-branes are wrapped on coassociative four-cycles of constant curvature in seven manifolds of G2 holonomy. The solutions preserve two supercharges and thus represent supergravity duals of three dimensional Yang-Mills with N=1 supersymmetry. When uplifted to eleven dimensions our solution describes M-theory on the background of an eight manifold with Spin(7) holonomy. (author)

  18. Technology cycles and technology revolutions

    Energy Technology Data Exchange (ETDEWEB)

    Paganetto, Luigi; Scandizzo, Pasquale Lucio

    2010-09-15

    Technological cycles have been characterized as the basis of long and continuous periods economic growth through sustained changes in total factor productivity. While this hypothesis is in part consistent with several theories of growth, the sheer magnitude and length of the economic revolutions experienced by humankind seems to indicate surmise that more attention should be given to the origin of major technological and economic changes, with reference to one crucial question: role of production and use of energy in economic development.

  19. Entrepreneurship and the Business Cycle

    OpenAIRE

    KOELLINGER, Philipp; Thurik, Roy

    2009-01-01

    This discussion paper resulted in a publication in 'The Review of Economics and Statistics' (2012). Volume 94, issue 4, pages 1143-1156. We study the cyclical pattern of entrepreneurial activity. Results across 22 OECD countries for the period 1972-2007 show that entrepreneurial activity is a leading indicator of the business cycle in a Granger-causality sense. This contradicts existing theoretical hypotheses which predict that entrepreneurship is pro-cyclical or not cyclical. We discuss poss...

  20. Immigration, remittances, and business cycles

    OpenAIRE

    Federico S. Mandelman; Zlate, Andrei

    2010-01-01

    We use data on border enforcement and macroeconomic indicators from the United States and Mexico to estimate a two-country business cycle model of labor migration and remittances. The model matches the cyclical dynamics of labor migration to the United States and documents how remittances to Mexico serve an insurance role to smooth consumption across the border. During expansions in the destination economy, immigration increases with the expected stream of future wage gains, but it is dampene...

  1. Cycling Behavior and Memory Formation

    OpenAIRE

    Gerstner, Jason R.; Lyons, Lisa C.; Wright, Kenneth P.; Loh, Dawn H; Rawashdeh, Oliver; Eckel-Mahan, Kristin L.; Roman, Gregg W.

    2009-01-01

    Circadian research has spent considerable effort in the determining clock output pathways, including identifying both physiological and behavioral processes that demonstrate significant time-of-day variation. Memory formation and consolidation represent notable processes shaped by endogenous circadian oscillators. To date, very few studies on memory mechanisms have considered potential confounding effects of time-of-day and the organism’s innate activity cycles (e.g., nocturnal, diurnal, or c...

  2. Cardiac Biomarkers and Cycling Race

    OpenAIRE

    Caroline Le Goff, Jean-François Kaux, Sébastien Goffaux, Etienne Cavalier

    2015-01-01

    In cycling as in other types of strenuous exercise, there exists a risk of sudden death. It is important both to understand its causes and to see if the behavior of certain biomarkers might highlight athletes at risk. Many reports describe changes in biomarkers after strenuous exercise (Nie et al., 2011), but interpreting these changes, and notably distinguishing normal physiological responses from pathological changes, is not easy. Here we have focused on the kinetics of different cardiac bi...

  3. Miller cycle analysis using EGM

    OpenAIRE

    Ribeiro, Bernardo Sousa; Martins, Jorge

    2005-01-01

    The Entropy Generation Minimization (EGM) method is based on the analysis by three sciences (thermodynamics, fluid flow and heat transfer) of the different processes that may occur in a system or in an equipment. Herein the EGM method is applied to internal combustion engines to determine the entropy generation caused by different processes. A model incorporating entropy generation calculations is used to assess various engines configurations. Otto cycle was tested and...

  4. Creative Cycling of News Professionals

    OpenAIRE

    Astrid Gynnild, PhD.

    2007-01-01

    The theory of creative cycling emerged from my PhD study of news professionals in Norway. The study was carried out according to classic grounded theory principles (Glaser and Strauss 1967, Glaser 1978, 1998, 2001, 2005), and the area of interest was the performance of news journalism in the multimedia age. The theory runs counter to widespread tendencies of industrial age thinking in news media. It emphasizes news professionals’ search for meaning in their daily work, and suggests that their...

  5. Sickness Absence and Business Cycles

    OpenAIRE

    Jan Erik Askildsen; Espen Bratberg; Oivind Anti Nilsen

    2000-01-01

    Absenteeism is affected by the sickness benefit system. Countries with generous compensation during sick leaves also experience high numbers of sick leave. Sick leaves may vary over the business cycle due to unemployment disciplining effects or changes in labour force composition. The latter hypothesis maintains that sickness may be pro-cyclical due to employment of `marginal' workers with poorer health when demand increases. Using individual records of labour force participants in Norway, we...

  6. Containing revenue-cycle costs.

    Science.gov (United States)

    Geer, Robert; Burton, Eric

    2003-04-01

    Healthcare organizations can achieve revenue-cycle improvement while maintaining optimum staffing levels by taking a three-step approach-developing a plan, measuring costs, and using benchmarks to measure performance. Planned cost reductions can be achieved without a negative impact on the organization. Cost-reduction strategies should look at purchased services, staffing, and the cost-to-collect ratio. Healthcare organizations should reach target performance levels before implementing a cost-reduction strategy.

  7. Fundamental cycles and graph embeddings

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, we investigate fundamental cycles in a graph G and their relations with graph embeddings. We show that a graph G may be embedded in an orientable surface with genus at least g if and only if for any spanning tree T , there exists a sequence of fundamental cycles C1, C2, . . . , C2g with C2i-1 ∩ C2i≠ф for 1≤ i ≤g. In particular, among β(G) fundamental cycles of any spanning tree T of a graph G, there are exactly 2γM (G) cycles C1, C2, . . . , C2γM (G) such that C2i-1 ∩ C2i≠ф for 1 ≤i≤γM (G), where β(G) and γM (G) are the Betti number and the maximum genus of G, respectively. This implies that it is possible to construct an orientable embedding with large genus of a graph G from an arbitrary spanning tree T (which may have very large number of odd components in G\\E(T )). This is different from the earlier work of Xuong and Liu, where spanning trees with small odd components are needed. In fact, this makes a common generalization of Xuong, Liu and Fu et al. Furthermore, we show that (1) this result is useful for locating the maximum genus of a graph having a specific edge-cut. Some known results for embedded graphs are also concluded; (2) the maximum genus problem may be reduced to the maximum matching problem. Based on this result and the algorithm of Micali-Vazirani, we present a new efficient algorithm to determine the maximum genus of a graph in O((β(G)) 25 ) steps. Our method is straight and quite different from the algorithm of Furst, Gross and McGeoch which depends on a result of Giles where matroid parity method is needed.

  8. Biogeochemical Cycles in Degraded Lands

    Science.gov (United States)

    Davidson, Eric A.; Vieira, Ima Celia G.; ReisdeCarvalho, Claudio Jose; DeanedeAbreuSa, Tatiana; deSouzaMoutinho, Paulo R.; Figueiredo, Ricardo O.; Stone, Thomas A.

    2004-01-01

    The objectives of this project were to define and describe the types of landscapes that fall under the broad category of "degraded lands" and to study biogeochemical cycles across this range of degradation found in secondary forests. We define degraded land as that which has lost part of its capacity of renovation of a productive ecosystem, either in the context of agroecosystems or as native communities of vegetation. This definition of degradation permits evaluation of biogeochemical constraints to future land uses.

  9. Product development cycle time reduction

    Science.gov (United States)

    Farran, Robin

    1992-05-01

    We are facing here today the key issues that face us in the competitive environment. North American companies are struggling to compete in the global marketplace. Gone are the days when presence ensured success. Then, sales and earnings were guaranteed. Today the competition is intense. Many manufacturing and service companies are no longer competitive. Traditionally, manufacturing companies have created the most wealth for the community and economy. Losing this ability to create wealth is tragic and unnecessary. A company can only be successful by focusing on customer satisfaction at competitive costs. Revenue growth and earnings growth require a continuous stream of products that anticipate the customers' needs, result from shorter and shorter innovation cycles, continually improve in quality, and are produced at improved costs on each cycle. The best opportunities for increased quality and decreased costs are with new products. Sure, work on quality and costs everyday. The biggest changes, however, will come through the new product development cycle. We must improve our development processes to provide leadership products which result in high levels of customer satisfaction. This is a prerequisite for business success. When presence in the marketplace was a virtual guarantee of success for a North American company, technology tended to drive the products, and the customers bought virtually everything that was produced. Functional excellence was stressed within companies ... and that was enough. Effective planning processes were not a prerequisite for success. Today success demands highly developed business research and planning processes, and functional excellence combined with organizational capabilities that ensure commercialization excellence.

  10. The parenting cycle of deployment.

    Science.gov (United States)

    DeVoe, Ellen R; Ross, Abigail

    2012-02-01

    Parents of dependent children comprise approximately 42% of Active Duty and National Guard/Reserve military members serving in Operation Iraqi Freedom/Operation Enduring Freedom. Recent estimates indicate that more than two million children have experienced parental deployment since the terrorist attacks on September 11, 2001. This article seeks to characterize the impact of the deployment life cycle on parenting roles among service members and at-home partners/caregivers of dependent children. Specifically, a new conceptual framework is presented for considering the ways in which parenting and co-parenting processes are affected by the demands and transitions inherent in contemporary deployment to a war zone. Although the phase-based emotional cycle of deployment continues to offer an instructive description of the broad challenges faced by military couples, a parenting cycle of deployment model shifts the perspective to the critical and largely ignored processes of parenting in the context of deployment and war, and to the realities faced by parents serving in the U.S. military. Implications for prevention, intervention, and future research related to military families are addressed. PMID:22360065

  11. Managing the strategic capital cycle.

    Science.gov (United States)

    Kaufman, K

    1997-12-01

    A healthcare organization's financial strategy should be defined within the context of the capital cycle and provide for the management of three critical components that will ensure the expansion and renewal of capital capacity--the design and implementation of the financial plan, the design and implementation of an appropriate capital structure, and a means to strategically utilize capital and reinvest it in the organization. The capital cycle comprises two parts--strategic planning and implementation, and the development of the support infrastructure that includes financial planning, capital structure, and capital allocation. The financial plan positions an organization within an area of financial equilibrium and defines its organizational capabilities. The financial infrastructure gives integrity and momentum to the capital cycle. Capital structure addresses critical funding and financing questions and is best defined as the combination of debt and equity that funds the strategic plan. In regard to capital allocation, healthcare organizations should follow a corporate "best practices" approach for such areas as financial objectives and policies, project review, and the capital expenditures approval process.

  12. ZPC Matrices and Zero Cycles

    Directory of Open Access Journals (Sweden)

    Marina Arav

    2009-01-01

    Full Text Available Let H be an m×n real matrix and let Zi be the set of column indices of the zero entries of row i of H. Then the conditions |Zk∩(∪i=1k−1Zi|≤1 for all k  (2≤k≤m are called the (row Zero Position Conditions (ZPCs. If H satisfies the ZPC, then H is said to be a (row ZPC matrix. If HT satisfies the ZPC, then H is said to be a column ZPC matrix. The real matrix H is said to have a zero cycle if H has a sequence of at least four zero entries of the form hi1j1,hi1j2,hi2j2,hi2j3,…,hikjk,hikj1 in which the consecutive entries alternatively share the same row or column index (but not both, and the last entry has one common index with the first entry. Several connections between the ZPC and the nonexistence of zero cycles are established. In particular, it is proved that a matrix H has no zero cycle if and only if there are permutation matrices P and Q such that PHQ is a row ZPC matrix and a column ZPC matrix.

  13. Endoreversible Meletis-Georgiou cycle

    Directory of Open Access Journals (Sweden)

    Chang Liu, Lingen Chen, Fengrui Sun

    2012-01-01

    Full Text Available An endoreversible Meletis-Georgiou (MG cycle model with constant specific heat of working fluid is established and the analytical formulae of performance parameters including working fluid temperatures, work output and efficiency are derived using the finite time thermodynamic theory. The performance of the endoreversible MG cycle is analyzed and optimized. The characteristics of the work output versus compression ratio, efficiency versus compression ratio, and work output versus efficiency are obtained, respectively, by detailed numerical examples, and the effects of changeover ratio, over-expansion ratio, heating value of fuel, heat transfer loss coefficient, initial temperature of working fluid, and the transferred volume ratio on the relationship mentioned above are also discussed. The maximum work output and the corresponding optimal compression ratio, changeover ratio, over-expansion ratio as well as the maximum efficiency and the corresponding optimal changeover ratio and over-expansion ratio are obtained by taking the cycle work output and efficiency as the optimization objectives, respectively. Moreover, the effects of the parameters such as the heating value of fuel, heat transfer loss coefficient, initial temperature of working fluid, and the transferred volume ratio on the maximum work output, the maximum efficiency and the corresponding optimal ratios are analyzed. The results may provide guidelines for the optimal design of practical MG engine.

  14. Nutrient cycling in mango trees

    Directory of Open Access Journals (Sweden)

    Cinara Xavier de Almeida

    2014-02-01

    Full Text Available Estimates of nutrient amounts both shedding and demanding replacement in the maintenance of productivity of fruit trees require studies on element dynamics within the many ecosystem components generally made up of nutrient cycling. Thus, it was the objective of this study to evaluate the nutrient biochemical cycling in a mango tree (Mangifera indica L. orchard, Palmer variety. Macronutrients [nitrogen (N, phosphorus (P, potassium (K, calcium (Ca, magnesium (Mg, and sulfur (S] had their contents evaluated in leaves at different stages: new, mature, senescent, and litter. First exploratory analysis was performed for main components which preserve the multivariate structure shown by the data. It was possible to observe the association of new leaves with N, P, K, Mg, and S; senescent leaves and the leaves from the litter were associated to Ca, while mature leaves, to K. As a complement, taking the independent variables into consideration, Tukey test (p?0.01 showed that the averages of N, P, and Ca differ between the new and the mature leaves; average of Mg in new leaves differs from the others, and S does not differ along the stages. Also observed was the re-translocation of 41%, 63% and 57% of N, P, and K, respectively, when comparison was made among the contents of the elements in mature leaves as well as in litter, which indicates that the biochemical cycling is important for the mango tree cultivation.

  15. Digital Daily Cycles of Individuals

    Science.gov (United States)

    Aledavood, Talayeh; Lehmann, Sune; Saramäki, Jari

    2015-10-01

    Humans, like almost all animals, are phase-locked to the diurnal cycle. Most of us sleep at night and are active through the day. Because we have evolved to function with this cycle, the circadian rhythm is deeply ingrained and even detectable at the biochemical level. However, within the broader day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We begin at the aggregate level, discuss earlier results, and illustrate differences between population-level daily rhythms in different media. Then we move on to the individual level, and show that there is a strong individual-level variation beyond averages: individuals typically have their distinctive daily pattern that persists in time. We conclude by discussing the driving forces behind these signature daily patterns, from personal traits (morningness/eveningness) to variation in activity level and external constraints, and outline possibilities for future research.

  16. Digital Daily Cycles of Individuals

    Directory of Open Access Journals (Sweden)

    Talayeh eAledavood

    2015-10-01

    Full Text Available Humans, like almost all animals, are phase-locked to the diurnal cycle. Most of us sleep at night and are active through the day. Because we have evolved to function with this cycle, the circadian rhythm is deeply ingrained and even detectable at the biochemical level. However, within the broader day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We begin at the aggregate level, discuss earlier results, and illustrate differences between population-level daily rhythms in different media. Then we move on to the individual level, and show that there is a strong individual-level variation beyond averages: individuals typically have their distinctive daily pattern that persists in time. We conclude by discussing the driving forces behind these signature daily patterns, from personal traits (morningness/eveningness to variation in activity level and external constraints, and outline possibilities for future research.

  17. Solar storms, cycles and topology

    Directory of Open Access Journals (Sweden)

    Lundstedt H.

    2010-12-01

    Full Text Available Solar storms are produced due to plasma processes inside and between coronal loops. These loops are topologically examined using knot and braid theory. Solar cycles are topologically explored with a complex generalization of the three ordinary differential equations studied by Lorenz. By studying the Poincaré map we give numerical evidence that the flow has an attractor with fractal structure. The period is defined as the time needed for a point on a hyperplane to return to the hyperplane again. The periods are distributed in an interval. For large values of the Dynamo number there is a long tail toward long periods and other interesting comet-like features. We also found a relationship between the intensity of a cycle and the length for the previous cycle. Maunder like minima are also appearing. These general relations found for periods can further be physically interpreted with improved helioseismic estimates of the parameters used by the dynamical systems. Solar Dynamic Observatory is expected to offer such improved measurements.

  18. Advanced Fuel Cycle Cost Basis

    Energy Technology Data Exchange (ETDEWEB)

    D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert; E. Schneider

    2009-12-01

    This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.

  19. Advanced Fuel Cycle Cost Basis

    Energy Technology Data Exchange (ETDEWEB)

    D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert; E. Schneider

    2008-03-01

    This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.

  20. Advanced Fuel Cycle Cost Basis

    Energy Technology Data Exchange (ETDEWEB)

    D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert

    2007-04-01

    This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 26 cost modules—24 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, and high-level waste.

  1. BUSINESS CYCLES, ELECTORAL CYCLES. TOWARD A THEORETICAL FRAME OF INTERACTION

    Directory of Open Access Journals (Sweden)

    BOGDAN-LUCIAN DOSPINESCU

    2015-06-01

    Full Text Available The idea of cyclical movement of a system: be it political, economic, institutional, is one of the constants of critical thinking. In this sense, there is a natural cyclic movement that cannot be avoided (only amplified or diminished and is connected with the nature of these systems. The economy follows a cyclical movement; a period of growth follows a period of decline, and so on. So does popularity for political parties or leaders. In this paper, I explore the links between the business cycles and electoral cycles. For this purpose, I introduce the concept of electoral perception cycles. My hypothesis is that popularity of political parties and leaders follow a cyclical evolution, both on short and long term. I show how perception cycles can impact the “political business cycle theory”. There is great interest in political science literature for the factors that influence the fluctuations in Presidents’ popularity, especially from United States. However, very little has been said about Romania’s case. I investigate the hypothesis of electoral perception cycles looking at the popularity of former president Traian Basescu, over his two terms. The variable used to measure popularity is favorability, measured in national surveys, done face to face, on representative samplez, of around 1000 subjects. I’ve correlated the fluctuations in favorability over time, with key public events or political decisions taken by Traian Băsescu. The main findings are as follows. Firstly, there are significant short term fluctuations (short term perception cycles and they are correlated with major events on the agenda. I would point the following key moments: 1. The referendum for dismissal of the President in May 2007 – Traian Băsescu’s favorability increased by 7 percentage points; 2. The referendum for unicameral Parliament with 300 MPs in the fall of 2009. Coupled with victory in the presidential election, it lead to an increase of 10 percentage

  2. High performance heat pump absorption cycles

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Longo, G.; Rossetto, L.

    1988-10-01

    Absorption heat pumps can provide high performances when operating in suitable cycles with multiple effects. This report describes some multistage cycles and evaluates the coefficient of performance realistically obtainable both in winter and summer working conditions.

  3. Not all counterclockwise thermodynamic cycles are refrigerators

    Science.gov (United States)

    Dickerson, R. H.; Mottmann, J.

    2016-06-01

    Clockwise cycles on PV diagrams always represent heat engines. It is therefore tempting to assume that counterclockwise cycles always represent refrigerators. This common assumption is incorrect: most counterclockwise cycles cannot be refrigerators. This surprising result is explored here for quasi-static ideal gas cycles, and the necessary conditions for refrigeration cycles are clarified. Three logically self-consistent criteria can be used to determine if a counterclockwise cycle is a refrigerator. The most fundamental test compares the counterclockwise cycle with a correctly determined corresponding Carnot cycle. Other criteria we employ include a widely accepted description of the functional behavior of refrigerators, and a corollary to the second law that limits a refrigerator's coefficient of performance.

  4. Biogeochemical cycles: Interactions in global metabolism

    Science.gov (United States)

    Moore, B., III; Morowitz, H.; Dastoor, M. N.

    1984-01-01

    A science that chooses the globe as it fundamental biogeophysical unit forces extraordinary conceptual difficulties. The roles of energy flow, matter cycles, carbon cycle, air pollution, global effects, air water interactions are discussed.

  5. Terminology gap in hydrological cycle

    Science.gov (United States)

    Zhuo, Lu; Han, Dawei

    2016-04-01

    Water is central to life on Earth. People have been trying to understand how water moves in the hydrosphere throughout the human history. In the 9th century BC, the famous Greek poet Homer described the hydrological cycle in Iliad as "okeanos whose stream bends back in a circle" with a belief that rivers are ocean-fed from subterranean seas. Later, Aristotle (4th century BC) claimed that most of the water came from underground caverns in which air was transformed into water. It was only until 1674, French scientist Perrault developed the correct concept of the water cycle. In modern times, scientists are interested in understanding the individual processes of the hydrological cycle with a keen focus on runoff which supplies water to rivers, lakes, and oceans. Currently, the prevailing concepts on runoff processes include 'infiltration excess runoff' and 'saturation excess runoff'. However, there is no term to describe another major runoff due to the excess beyond the soil water holding capacity (i.e., the field capacity). We argue that a new term should be introduced to fill this gap, and it could be called 'holding excess runoff' which is compatible with the convention. This new term is significant in correcting a half-century misnomer where 'holding excess runoff' has been incorrectly named as 'saturation excess runoff', which was introduced by the Xinanjiang model in China in 1960s. Similar concept has been adopted in many well-known hydrological models such as PDM and HBV in which the saturation refers to the field capacity. The term 'holding excess runoff' resolves such a common confusion in the hydrological community.

  6. Fundamental cycles and graph embeddings

    Institute of Scientific and Technical Information of China (English)

    REN Hani; ZHAO HongTao; LI HaoLing

    2009-01-01

    In this paper, we investigate fundamental cycles in a graph G and their relations with graph embeddings. We show that a graph G may be embedded in an orientable surface with genus at least g if and only if for any spanning tree T, there exists a sequence of fundamental cycles of any spanning tree T of a graph G, there are exactly 2γM(G) cycles G1,G2,…,C2γM(G) such that C2i-1 ∩ C2i≠ for 1≤I≤γM(G), where β(G) and γM(G) are the Betti number and the maximum genus of G, respectively. This implies that it is possible to construct an orientable embedding with large genus of a graph G from an arbitrary spanning tree T (which may have very large number of odd components in G\\E(T)). This is different from the earlier work of Xuong and Liu, where spanning trees with small odd components are needed. In fact, this makes a common generalization of Xuong, Liu and Fu et al. Furthermore, we show that (1) this result is useful for locating the maximum genus of a graph having a specific edge-cut. Some known results for embedded graphs are also concluded; (2) the maximum genus problem may be reduced to the maximum matching problem. Based on this result and the algorithm of Micali-Vazirani, we present a new efficient algorithm to determine the maximum genus of a graph in O((β(G))5/2) steps. Our method is straight and quite different from the algorithm of Furst, Gross and McGeoch which depends on a result of Giles where matroid parity method is needed.

  7. Rankine cycle system and method

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Nelson, Christopher R.

    2014-09-09

    A Rankine cycle waste heat recovery system uses a receiver with a maximum liquid working fluid level lower than the minimum liquid working fluid level of a sub-cooler of the waste heat recovery system. The receiver may have a position that is physically lower than the sub-cooler's position. A valve controls transfer of fluid between several of the components in the waste heat recovery system, especially from the receiver to the sub-cooler. The system may also have an associated control module.

  8. The biogeochemistry of metal cycling

    Science.gov (United States)

    Nealson, Kenneth H. (Editor); Nealson, Molly (Editor); Dutcher, F. Ronald (Editor)

    1990-01-01

    The results of the Planetary Biology and Microbial Ecology's summer 1987 program are summarized. The purpose of the interdisciplinary PBME program is to integrate, via lectures and laboratory work, the contributions of university and NASA scientists and student interns. The 1987 program examined various aspects of the biogeochemistry of metal cycling, and included such areas as limnology, metal chemistry, metal geochemistry, microbial ecology, and interactions with metals. A particular area of focus was the use of remote sensing in the study of biogeochemistry. Abstracts and bibliographies of the lectures and reports of the laboratory projects are presented.

  9. Heteroclinic Cycles in Hopfield Networks

    Science.gov (United States)

    Chossat, Pascal; Krupa, Maciej

    2016-04-01

    It is widely believed that information is stored in the brain by means of the varying strength of synaptic connections between neurons. Stored patterns can be replayed upon the arrival of an appropriate stimulus. Hence, it is interesting to understand how an information pattern can be represented by the dynamics of the system. In this work, we consider a class of network neuron models, known as Hopfield networks, with a learning rule which consists of transforming an information string to a coupling pattern. Within this class of models, we study dynamic patterns, known as robust heteroclinic cycles, and establish a tight connection between their existence and the structure of the coupling.

  10. Search for relationship between duration of the extended solar cycles and amplitude of sunspot cycle

    CERN Document Server

    Tlatov, A G

    2007-01-01

    Duration of the extended solar cycles is taken into the consideration. The beginning of cycles is counted from the moment of polarity reversal of large-scale magnetic field in high latitudes, occurring in the sunspot cycle n till the minimum of the cycle n+2. The connection between cycle duration and its amplitude is established. Duration of the "latent" period of evolution of extended cycle between reversals and a minimum of the current sunspot cycle is entered. It is shown, that the latent period of cycles evolution is connected with the next sunspot cycle amplitude and can be used for the prognosis of a level and time of a sunspot maximum. The 24-th activity cycle prognosis is done. Long-term behavior of extended cycle's lengths is considered.

  11. Multiple Limit Cycles in an Immune System

    Institute of Scientific and Technical Information of China (English)

    Xun-cheng Huang; Le-min Zhu; Minaya Villasana

    2008-01-01

    The nonlinear oscillatory phenomenon has been observed in the system of immune response, which corresponds to the limit cycles in the mathematical models. We prove that the system simulating an immune response studied by Huang has at least three limit cycles in the system. The conditions for the multiple limit cycles are useful in analyzing the nonlinear oscillation in immune response.

  12. The next generation of revenue cycle management.

    Science.gov (United States)

    Hammer, David C

    2007-07-01

    The revenue cycle management environment is dynamic. Revenue cycle leaders are now responsible for additional functional areas and have to deal with new financing arrangements that expose the organization to greater financial risk. Financial managers can use key performance indicators and the suggested practice processes checklist to determine whether their revenue cycle operations are in good shape or need shaping up.

  13. Does It Have a Life Cycle?

    Science.gov (United States)

    Keeley, Page

    2010-01-01

    If life continues from generation to generation, then all plants and animals must go through a life cycle, even though it may be different from organism to organism. Is this what students have "learned," or do they have their own private conceptions about life cycles? The formative assessment probe "Does It Have a Life Cycle?" reveals some…

  14. Dormancy cycling in seeds: mechanisms and regulation

    NARCIS (Netherlands)

    Claessens, S.M.C.

    2012-01-01

    The life cycle of most plants starts, and ends, at the seed stage. In most species mature seeds are shed and dispersed on the ground. At this stage of its life cycle the seed may be dormant and will, by definition, not germinate under favourable conditions (Bewley, 1997). Seasonal dormancy cycling

  15. Combined cycles with gas turbine engines

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, Y.S.H.; Akyurt, M. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Mechanical Engineering Dept.)

    1994-03-01

    Simple cycle gas turbine engines suffer from limited efficiencies and consequential dominance of fuel prices on generation costs. Combined cycles, however. exploit the waste heat from exhaust gases to boost power output, resulting in overall efficiencies around 50%, which are significantly above those of steam power plants. This paper reviews various types of combined cycles, including repowering, integrated gasification and other advanced systems. (author)

  16. Kinetic models of conjugated metabolic cycles

    Science.gov (United States)

    Ershov, Yu. A.

    2016-01-01

    A general method is developed for the quantitative kinetic analysis of conjugated metabolic cycles in the human organism. This method is used as a basis for constructing a kinetic graph and model of the conjugated citric acid and ureapoiesis cycles. The results from a kinetic analysis of the model for these cycles are given.

  17. Hopf limit cycles estimation in power systems

    Energy Technology Data Exchange (ETDEWEB)

    Barquin, J.; Gomez, T.; Pagola, L.F. [Univ. Pontificia Comillas, Madrid (Spain). Inst. de Investigacion Tecnologica

    1995-11-01

    This paper addresses the computation of the Hopf limit cycle. This limit cycle is associated to the appearance of an oscillatory instability in dynamical power systems. An algorithm is proposed to estimate the dimensions and shape of this limit cycle. The algorithm is computationally efficient and is able to deal with large power systems. 7 refs, 4 figs, 1 tab

  18. On Acyclicity of Games with Cycles

    DEFF Research Database (Denmark)

    Andersson, Daniel; Gurvich, Vladimir; Hansen, Thomas Dueholm

    2009-01-01

    We study restricted improvement cycles (ri-cycles) in finite positional n-person games with perfect information modeled by directed graphs (digraphs) that may contain cycles. We obtain criteria of restricted improvement acyclicity (ri-acyclicity) in two cases: for n = 2 and for acyclic digraphs. We...

  19. Rock weathering and Carbon cycle

    Science.gov (United States)

    Strozza, Patrick

    2010-05-01

    In the history of the Earth system, we can find indicators of hot or glacial periods, as well as brutal climatic change… How can we explain those climate variations on a geological timescale ? One of the causative agents is probably the fluctuation of atmospheric CO2 amounts, (gas responsible for the greenhouse effect). A concrete study of some CO2 fluxes between Earth system reservoirs (atmo, hydro and lithosphere) is proposed in this poster. Hydrogencarbonate is the major ion in river surface waters and its amount is so high that it can not be explained by a simple atmospheric Carbon diffusion. From a simple measurement of river HCO3- concentration, we can estimate the consumption of atmospheric CO2 that arises from carbonate and silicate weathering processes. Practical experiments are proposed. These are carried out in the local environment, and are conform to the curriculums of Chemistry and Earth sciences. These tests enable us to outline long-term Carbon cycles and global climatic changes. Key words : Erosion, rock weathering, CO2 cycle, Hydrogencarbonate in waters, climatic changes

  20. Social Life Cycle Assessment Revisited

    Directory of Open Access Journals (Sweden)

    Ruqun Wu

    2014-07-01

    Full Text Available To promote the development of Social Life Cycle Assessment (SLCA, we conducted a comprehensive review of recently developed frameworks, methods, and characterization models for impact assessment for future method developers and SLCA practitioners. Two previous reviews served as our foundations for this review. We updated the review by including a comprehensive list of recently-developed SLCA frameworks, methods and characterization models. While a brief discussion from goal, data, and indicator perspectives is provided in Sections 2 to 4 for different frameworks/methods, the focus of this review is Section 5 where discussion on characterization models for impact assessment of different methods is provided. The characterization models are categorized into two types following the UNEP/SETAC guidelines: type I models without impact pathways and type II models with impact pathways. Different from methods incorporating type I/II characterization models, another LCA modeling approach, Life Cycle Attribute Assessment (LCAA, is also discussed in this review. We concluded that methods incorporating either type I or type II models have limitations. For type I models, the challenge lies in the systematic identification of relevant stakeholders and materiality issues; while for type II models, identification of impact pathways that most closely and accurately represent the real-world causal relationships is the key. LCAA may avoid these problems, but the ultimate questions differ from those asked by the methods using type I and II models.

  1. Life Cycle Assessment of Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Sjunnesson, Jeannette

    2005-09-15

    This is an environmental study on concrete that follows the standard protocol of life cycle assessment (LCA). The study is done for two types of concrete, ordinary and frost-resistant concrete, and has an extra focus on the superplasticizers used as admixtures. The utilization phase is not included in this study since the type of construction for which the concrete is used is not defined and the concrete is assumed to be inert during this phase. The results show that it is the production of the raw material and the transports involved in the life cycle of concrete that are the main contributors to the total environmental load. The one single step in the raw material production that has the highest impact is the production of cement. Within the transportation operations the transportation of concrete is the largest contributor, followed by the transportation of the cement. The environmental impact of frost-resistant concrete is between 24-41 % higher than that of ordinary concrete due to its higher content of cement. Superplasticizers contribute with approximately 0.4-10.4 % of the total environmental impact of concrete, the least to the global warming potential (GWP) and the most to the photochemical ozone creation potential (POCP). Also the toxicity of the superplasticizers is investigated and the conclusion is that the low amount of leakage of superplasticizers from concrete leads to a low risk for the environment and for humans.

  2. Technology development life cycle processes.

    Energy Technology Data Exchange (ETDEWEB)

    Beck, David Franklin

    2013-05-01

    This report and set of appendices are a collection of memoranda originally drafted in 2009 for the purpose of providing motivation and the necessary background material to support the definition and integration of engineering and management processes related to technology development. At the time there was interest and support to move from Capability Maturity Model Integration (CMMI) Level One (ad hoc processes) to Level Three. As presented herein, the material begins with a survey of open literature perspectives on technology development life cycles, including published data on %E2%80%9Cwhat went wrong.%E2%80%9D The main thrust of the material presents a rational expose%CC%81 of a structured technology development life cycle that uses the scientific method as a framework, with further rigor added from adapting relevant portions of the systems engineering process. The material concludes with a discussion on the use of multiple measures to assess technology maturity, including consideration of the viewpoint of potential users.

  3. MHD Integrated Topping Cycle Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The overall objective of the project is to design and construct prototypical hardware for an integrated MHD topping cycle, and conduct long duration proof-of-concept tests of integrated system at the US DOE Component Development and Integration Facility in Butte, Montana. The results of the long duration tests will augment the existing engineering design data base on MHD power train reliability, availability, maintainability, and performance, and will serve as a basis for scaling up the topping cycle design to the next level of development, an early commercial scale power plant retrofit. The components of the MHD power train to be designed, fabricated, and tested include: A slagging coal combustor with a rated capacity of 50 MW thermal input, capable of operation with an Eastern (Illinois {number sign}6) or Western (Montana Rosebud) coal, a segmented supersonic nozzle, a supersonic MHD channel capable of generating at least 1.5 MW of electrical power, a segmented supersonic diffuser section to interface the channel with existing facility quench and exhaust systems, a complete set of current control circuits for local diagonal current control along the channel, and a set of current consolidation circuits to interface the channel with the existing facility inverter.

  4. MHD Integrated Topping Cycle Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    The Magnetohydrodynamics (MHD) Integrated Topping Cycle (ITC) Project represents the culmination of the proof-of-concept (POC) development stage in the US Department of Energy (DOE) program to advance MHD technology to early commercial development stage utility power applications. The project is a joint effort, combining the skills of three topping cycle component developers: TRW, Avco/TDS, and Westinghouse. TRW, the prime contractor and system integrator, is responsible for the 50 thermal megawatt (50 MW{sub t}) slagging coal combustion subsystem. Avco/TDS is responsible for the MHD channel subsystem (nozzle, channel, diffuser, and power conditioning circuits), and Westinghouse is responsible for the current consolidation subsystem. The ITC Project will advance the state-of-the-art in MHD power systems with the design, construction, and integrated testing of 50 MW{sub t} power train components which are prototypical of the equipment that will be used in an early commercial scale MHD utility retrofit. Long duration testing of the integrated power train at the Component Development and Integration Facility (CDIF) in Butte, Montana will be performed, so that by the early 1990's, an engineering data base on the reliability, availability, maintainability and performance of the system will be available to allow scaleup of the prototypical designs to the next development level. This Sixteenth Quarterly Technical Progress Report covers the period May 1, 1991 to July 31, 1991.

  5. Water Cycling &the GPM Mission

    Science.gov (United States)

    Smith, E. A.

    2003-04-01

    The GPM mission is currently planned for start in the late'07 - early'08 time frame. Its main scientific goal is to help answer pressing scientific problems arising within the context of global and regional water cycles. These problems cut across a hierarchy of scales and include climate-water cycle interactions, techniques for improving weather and climate predictions, and better methods for combining observed precipitation with hydrometeorological prediction models for applications to hazardous flood-producing storms, seasonal flood/draught conditions, and fresh water resource assessments. The GPM mission will expand the scope of precipitation measurement through the use of a constellation of some 9 satellites, one of which will be an advanced TRMM-like "core" satellite carrying a dual-frequency Ku-Ka band precipitation radar and an advanced, multifrequency passive microwave radiometer with vertical-horizontal polarization discrimination. The other constellation members will include new dedicated satellites and co-existing operational/research satellites carrying similar (but not identical) passive microwave radiometers. The goal of the constellation is to achieve 3-hour sampling at any spot on the globe - continuously. The constellation's orbit architecture will consist of a mix of sun-synchronous and non-sun-synchronous satellites with the "core" satellite providing measurements of cloud-precipitation microphysical processes plus calibration-quality rainrates to be used with the other retrieval information to ensure bias-free constellation coverage. GPM is organized internationally, involving existing, pending, projected, and under-study partnerships which will link NASA and NOAA in the US, NASDA in Japan, ESA in Europe, ISRO in India, CNES in France, and possibly ASI in Italy, KARI in South Korea, CSA in Canada, and AEB in Brazil. Additionally, the program is actively pursuing agreements with other international collaborators and domestic scientific agencies

  6. Advanced Fuel Cycle Economic Sensitivity Analysis

    Energy Technology Data Exchange (ETDEWEB)

    David Shropshire; Kent Williams; J.D. Smith; Brent Boore

    2006-12-01

    A fuel cycle economic analysis was performed on four fuel cycles to provide a baseline for initial cost comparison using the Gen IV Economic Modeling Work Group G4 ECON spreadsheet model, Decision Programming Language software, the 2006 Advanced Fuel Cycle Cost Basis report, industry cost data, international papers, the nuclear power related cost study from MIT, Harvard, and the University of Chicago. The analysis developed and compared the fuel cycle cost component of the total cost of energy for a wide range of fuel cycles including: once through, thermal with fast recycle, continuous fast recycle, and thermal recycle.

  7. Design and Fabrication of Eu-Cycle

    Directory of Open Access Journals (Sweden)

    A.Venkat Sai

    2014-10-01

    Full Text Available EU-Cycle is a self balancing electric unicycle. A regular unicycle is powered by pedal and is balanced by a rider, whilst the EU-Cycle runs by an electric motor and balance by control system in the roll direction. The simple thing to do by rider is to lean forward for acceleration, to lean backward for braking. EU-Cycle is designed as to be a fast and portable means of transport among crowded area, home and office. Therefore, The EU-Cycle gives tough challenge to the unicycle. EU-Cycle has attracted print media including future stories in radio, television. Thus in addition to successful development of EU-Cycle in urban use, the project has to implement the EU-cycle as an educative device.

  8. A class of internally irreversible refrigeration cycles

    Science.gov (United States)

    Ait-Ali, Mohand A.

    1996-03-01

    A Carnot-like irreversible refrigeration cycle is modelled with two isothermal and two non-adiabatic, irreversible processes. The generic source of internal irreversibility, measured by the Clausius inequality, is a general irreversibility term which could include any heat leaks into the Joule - Thompson expansion valve, the evaporator and compressor cold boxes. This cycle is optimized first for maximum refrigeration power and maximum refrigeration load, then for maximum coefficient of performance. Its performances are compared with those of the endoreversible refrigeration cycle, based on a propane stage of a classical cascade liquefaction cycle example. Both cycle models achieve optimum power and maximum refrigeration load at nearly the same refrigeration temperature, but only the coefficient of performance of the irreversible refrigeration cycle reaches a maximum. Moreover, its prediction of heat conductance allocation between evaporator and condenser appears to be not only more conservative, but also more realistic for actual design considerations of refrigeration cycles.

  9. Search for relationship between duration of the extended solar cycles and amplitude of sunspot cycle

    OpenAIRE

    Tlatov, A. G.

    2007-01-01

    Duration of the extended solar cycles is taken into the consideration. The beginning of cycles is counted from the moment of polarity reversal of large-scale magnetic field in high latitudes, occurring in the sunspot cycle n till the minimum of the cycle n+2. The connection between cycle duration and its amplitude is established. Duration of the "latent" period of evolution of extended cycle between reversals and a minimum of the current sunspot cycle is entered. It is shown, that the latent ...

  10. Fuel Cycle System Analysis Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Steven J. Piet; Brent W. Dixon; Dirk Gombert; Edward A. Hoffman; Gretchen E. Matthern; Kent A. Williams

    2009-06-01

    This Handbook aims to improve understanding and communication regarding nuclear fuel cycle options. It is intended to assist DOE, Campaign Managers, and other presenters prepare presentations and reports. When looking for information, check here. The Handbook generally includes few details of how calculations were performed, which can be found by consulting references provided to the reader. The Handbook emphasizes results in the form of graphics and diagrams, with only enough text to explain the graphic, to ensure that the messages associated with the graphic is clear, and to explain key assumptions and methods that cause the graphed results. Some of the material is new and is not found in previous reports, for example: (1) Section 3 has system-level mass flow diagrams for 0-tier (once-through), 1-tier (UOX to CR=0.50 fast reactor), and 2-tier (UOX to MOX-Pu to CR=0.50 fast reactor) scenarios - at both static and dynamic equilibrium. (2) To help inform fast reactor transuranic (TRU) conversion ratio and uranium supply behavior, section 5 provides the sustainable fast reactor growth rate as a function of TRU conversion ratio. (3) To help clarify the difference in recycling Pu, NpPu, NpPuAm, and all-TRU, section 5 provides mass fraction, gamma, and neutron emission for those four cases for MOX, heterogeneous LWR IMF (assemblies mixing IMF and UOX pins), and a CR=0.50 fast reactor. There are data for the first 10 LWR recycle passes and equilibrium. (4) Section 6 provides information on the cycle length, planned and unplanned outages, and TRU enrichment as a function of fast reactor TRU conversion ratio, as well as the dilution of TRU feedstock by uranium in making fast reactor fuel. (The recovered uranium is considered to be more pure than recovered TRU.) The latter parameter impacts the required TRU impurity limits specified by the Fuels Campaign. (5) Section 7 provides flows for an 800-tonne UOX separation plant. (6) To complement 'tornado' economic

  11. The effect of turbo trainer cycling on pedalling technique and cycling efficiency.

    Science.gov (United States)

    Arkesteijn, M; Hopker, J; Jobson, S A; Passfield, L

    2013-06-01

    Cycling can be performed on the road or indoors on stationary ergometers. The purpose of this study was to investigate differences in cycling efficiency, muscle activity and pedal forces during cycling on a stationary turbo trainer compared with a treadmill. 19 male cyclists cycled on a stationary turbo trainer and on a treadmill at 150, 200 and 250 W. Cycling efficiency was determined using the Douglas bags, muscle activity patterns were determined using surface electromyography and pedal forces were recorded with instrumented pedals. Treadmill cycling induced a larger muscular contribution from Gastrocnemius Lateralis, Biceps Femoris and Gluteus Maximus of respectively 14%, 19% and 10% compared with turbo trainer cycling (pcycling induced larger muscular contribution from Vastus Lateralis, Rectus Femoris and Tibialis Anterior of respectively 7%, 17% and 14% compared with treadmill cycling (pcycling was observed. These results suggest that cycling technique and type of ergometer can be altered without affecting cycling efficiency.

  12. The evolution of nitrogen cycling

    Science.gov (United States)

    Mancinelli, Rocco L.; Mckay, Christopher P.

    1988-01-01

    The energetics of nitrogen transformation reactions and the evolution of nitrogen cycling are examined. It is suggested that meteor impact-produced fixed nitrogen could have caused the entire reservoir of the earth's N2 to convert into fixed nitrogen at the end of accretion. The abiotic fixation rate on the early earth by lightning is estimated at about 1-3 X 10 to the 16th molecules of NO/J. It is found that biological nitrogen fixation may have evolved after the development of an aerobic atmosphere. It is shown that HNO could eventually become NO2(-) and NO3(-) after reaching the earth's surface. It is concluded that the evolutionary sequence for the biological transformation of nitrogen compounds is ammonification - denitrification - nitrification - nitrogen fixation.

  13. Thorium nuclear fuel cycle technology

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Tae Yoon; Do, Jae Bum; Choi, Yoon Dong; Park, Kyoung Kyum; Choi, In Kyu; Lee, Jae Won; Song, Woong Sup; Kim, Heong Woo

    1998-03-01

    Since thorium produces relatively small amount of TRU elements after irradiation in the reactor, it is considered one of possible media to mix with the elements to be transmuted. Both solid and molten-salt thorium fuel cycles were investigated. Transmutation concepts being studied involved fast breeder reactor, accelerator-driven subcritical reactor, and energy amplifier with thorium. Long-lived radionuclides, especially TRU elements, could be separated from spent fuel by a pyrochemical process which is evaluated to be proliferation resistance. Pyrochemical processes of IFR, MSRE and ATW were reviewed and evaluated in detail, regarding technological feasibility, compatibility of thorium with TRU, proliferation resistance, their economy and safety. (author). 26 refs., 22 figs

  14. Business cycles in oil economies

    Energy Technology Data Exchange (ETDEWEB)

    Al-Mutairi, N.H.

    1991-01-01

    This study examines the impact of oil price shocks on output fluctuations of several oil-exporting economies. In most studies of business cycles, the role of oil price is ignored; the few studies that use oil price as one of the variables in the system focus on modeling oil-importing economies. The vector autoregression (VAR) technique is used to consider the cases of Norway, Nigeria, and Mexico. Both atheoretical and structural' VARs are estimated to determine the importance of oil price impulses on output variations. The study reports two types of results: variance decomposition and impulse response functions, with particular emphasis on the issues of stationarity and co-integration among the series. The empirical results suggest that shocks to oil price are important in explaining output variations. In most cases, shocks to oil price are shown to explain more than 20% of the forecast variance of output over a 40-quarter horizon.

  15. Violence as a Vicious Cycle

    Directory of Open Access Journals (Sweden)

    Huseyin Gulec

    2012-03-01

    Full Text Available Since the conclusion that the violence as a behavior is not (cannot be determined within an absolute genetic determinism has been reached for long years, environmental factors are increasingly examined. We witness that human behavior in society can easily convert into coping with stressful events with violence. Individual or social violence as a behavior has a similar pattern with violence committed in primitive society and by children. After a brief review of violence, its description, etiological theories and types, this article majorly focuses on children and their early and late response to violence. The purpose here is to draw attention to the individuals who were previously exposed to violence (either directly or indirectly resort to violence, perpetuating a vicious cycle.

  16. Canard cycles in global dynamics

    CERN Document Server

    Vidal, Alexandre

    2009-01-01

    Fast-slow systems are studied usually by "geometrical dissection". The fast dynamics exhibit attractors which may bifurcate under the influence of the slow dynamics which is seen as a parameter of the fast dynamics. A generic solution comes close to a connected component of the stable invariant sets of the fast dynamics. As the slow dynamics evolves, this attractor may lose its stability and the solution eventually reaches quickly another connected component of attractors of the fast dynamics and the process may repeat. This scenario explains quite well relaxation and bursting oscillations. More recently, in relation both with theory of dynamical systems and with applications to physiology, a new interest has emerged in canard cycles. These orbits share the property that they remain for a while close to an unstable invariant set (either singular set or periodic orbits of the fast dynamics). Although canards were first discovered when the transition points are folds, in this article, we focus on the case where...

  17. Fuel cycle of the AVR

    International Nuclear Information System (INIS)

    All the stages of development were secured by irradiation tests and by the use of the elements concerned in the AVR. Summarising, these were: The first charge with fuel elements from Union Carbide, with U-Th mixed carbide particles, wallpaper variants, U-Th mixed carbide particles, the pressed fuel element with U-Th mixed carbide particles, the pressed fuel element with U-Th mixed oxide particles, with an intermediate boundary layer; the present THTR element, the pressed fuel element with U-Th mixed oxide particles and low temperature PyC coating, the pressed fuel element with U-Th mixed oxide particles, with PyC and SiC layers, i.e.: TRISO particles, the pressed fuel element with pure uranium oxide particles for the low enrichment cycle, one coated only by 2 PyC layers, the other coated with PyC and SiC, i.e.: TRISO coating. (orig.)

  18. MAPK uncouples cell cycle progression from cell spreading and cytoskeletal organization in cycling cells

    OpenAIRE

    Margadant, Coert; Cremers, Lobke; Sonnenberg, Arnoud; Boonstra, Johannes

    2012-01-01

    Integrin-mediated cytoskeletal tension supports growth-factor-induced proliferation, and disruption of the actin cytoskeleton in growth factor-stimulated cells prevents the re-expression of cyclin D and cell cycle re-entry from quiescence. In contrast to cells that enter the cell cycle from G0, cycling cells continuously express cyclin D, and are subject to major cell shape changes during the cell cycle. Here, we investigated the cell cycle requirements for cytoskeletal tension and cell sprea...

  19. Allele frequencies of 5 short tandem repeat loci of Kashin-Beck disease patients on chromosome 12%大骨节病患者12号染色体5个短串联重复序列位点基因频率分析

    Institute of Scientific and Technical Information of China (English)

    平智广; 刘莉; 郭雄

    2008-01-01

    Objective To analyze the allele frequencies of 5 short tandem repeat(STR)loci(D12S313,D12S304,D12S1640,D12S1708 and D12S1583)on chromosome 12 among Kashin-Beck disease(KBD)patients and the control population living in the area suffered from KBD.Methods Fifty KBD patient8 and 50 non-KBD patients were chosen in endemic afea of Shaanxi Province,5 STR loci on chromosome 12 were genotyped by the technology of polymerase chain reacfion(PCR)and capillary electmphoresis.The pelymorphisms of STR in these popIllations were analyzed.The allele and genotype frequencies of each STR in the corresponding groups were caleulated and compared. Results In KBD group,the 5 STR loci had 8,6,7,5 and 11 types ofalleles and 17,11,15,8 and 28 genotypes, respectively;while in the control group,the number of aUele types of 5 STR loci were 6,8,6,4 and 10,the number of genotype of those loci were 13,21,14,8 and 23,respectively The allele frequence of D12S304 locus was statiBtically significant between KBD patients and controls(P<0.05),especially for the 319 bp allele(P<0.006 25). Conclusion There is an association between D12S304 locus and KBD.The 319 bp allele might play the key role.%目的 分析大骨节病(Kashin-Beck disease,KBD)病区患者与非患者在12号染色体上5个短串联重复序列(short tandem repeat,STR)位点的多态性并比较其差异.方法 在陕西省KBD病区选择KBD患者(病例组)和非KBD患者(对照组)各50人,采集静脉血,利用PCR扩增和毛细管电泳技术,对12号染色体上5个STR位点(D12S313、D12S304、D12S1640、D12S1708和D12S1583)进行分型,分析各位点在上述人群中的多态性,计算5个位点在相应人群中等位基因与基因型频率,对各位点的等位基冈及基因型频率进行比较.结果 上述5种位点,病例组分别检出8,6、7、5和11种等位基因以及17、11、15、8和28种基因型;在对照组中检出6、8、6、4和10种等位基因以及13、21、14、8和23种基因型;在D12S304位点,病

  20. Solar Cycle Predictions Near Sunspot Minimum

    Science.gov (United States)

    Hathaway, David H.

    1997-01-01

    Observations of solar magnetic activity and the dynamics of the solar convection zone have produced severe constraints on models of the Sun's magnetic dynamo. These constraints are so severe that, at present, we do not have numerical models that can accept the current conditions and then march forward in time to predict future activity. Given this state of solar dynamo theory we are forced to examine previous behavior to discover patterns and trends that afford us some measure of predictability. Here we examine the behavior of several indicators of solar activity near solar minimum that are well correlated with the amplitude of the following solar maximum to predict the level of solar activity over cycle 23. Sunspot numbers, areas, and positions are useful for characterizing solar cycle behavior due to the extent of the data (12 cycles or more). These data exhibit several patterns that relate future activity to past behavior. With the Odd-Even effect the odd numbered cycles have been larger than their even numbered predecessors for each of the last six cycle pairs. With the Amplitude-Period effect short period cycles have been followed by large amplitude cycles and long period cycles have been followed by small amplitude cycles for 10 of the last 13 cycles. With the Maximum-Minimum effect the sunspot number at minimum is directly correlated with the sunspot number at maximum for a given cycle. The geomagnetic indices aa and Ap are also related to solar activity by the connections between disturbances in the solar wind and variations in the Earth's magnetic field. Like the Maximum-Minimum effect for sunspots, the size of the aa and Ap indices at minimum are directly related to the amplitude of the following maximum. The number of geomagnetically disturbed days (days with Ap >= 25) over the course of a cycle is another indicator for the size of the next cycle. The aa and Ap indices can each be separated into a component in phase with the current sunspot cycle and an

  1. Battery charging in float vs. cycling environments

    Energy Technology Data Exchange (ETDEWEB)

    COREY,GARTH P.

    2000-04-20

    In lead-acid battery systems, cycling systems are often managed using float management strategies. There are many differences in battery management strategies for a float environment and battery management strategies for a cycling environment. To complicate matters further, in many cycling environments, such as off-grid domestic power systems, there is usually not an available charging source capable of efficiently equalizing a lead-acid battery let alone bring it to a full state of charge. Typically, rules for battery management which have worked quite well in a floating environment have been routinely applied to cycling batteries without full appreciation of what the cycling battery really needs to reach a full state of charge and to maintain a high state of health. For example, charge target voltages for batteries that are regularly deep cycled in off-grid power sources are the same as voltages applied to stand-by systems following a discharge event. In other charging operations equalization charge requirements are frequently ignored or incorrectly applied in cycled systems which frequently leads to premature capacity loss. The cause of this serious problem: the application of float battery management strategies to cycling battery systems. This paper describes the outcomes to be expected when managing cycling batteries with float strategies and discusses the techniques and benefits for the use of cycling battery management strategies.

  2. A comparison of advanced heat recovery power cycles in a combined cycle for large ships

    DEFF Research Database (Denmark)

    Larsen, Ulrik; Sigthorsson, Oskar; Haglind, Fredrik

    2014-01-01

    Strong motivation exists within the marine sector to reduce fuel expenses and to comply with ever stricter emission regulations. Heat recovery can address both of these issues. The ORC (organic Rankine cycle), the Kalina cycle and the steam Rankine cycle have received the majority of the focus...... in the literature. In the present work we compare these cycles in a combined cycle application with a large marine two-stroke diesel engine. We present an evaluation of the efficiency and the environmental impact, safety concerns and practical aspects of each of the cycles. A previously validated numerical engine...... model is combined with a turbocharger model and bottoming cycle models written in Matlab. Genetic algorithm optimisation results suggest that the Kalina cycle possess no significant advantages compared to the ORC or the steam cycle. While contributing to very high efficiencies, the organic working...

  3. Thermodynamic Analysis of Combined Cycle Power Plant

    Directory of Open Access Journals (Sweden)

    A.K.Tiwari,

    2010-04-01

    Full Text Available Air Bottoming Cycle (ABC can replace the heat recovery steam generator and the steam turbine of the conventionalcombined cycle plant. The exhaust energy of the topping gas turbine of existing combine cycle is sent to gas-air heat exchange, which heats the air in the secondary gas turbine cycle. In 1980’s the ABC was proposed as an alternative for the conventional steam bottoming cycle. In spite of the cost of reducing hardware installations it could achieve a thermal efficiency of 80%. The complete thermodynamic analysis of the system has been performed by using specially designed programme, enabling the variation of main independent variables. The result shows the gain in net work output as well as efficiency of combined cycle is 35% to 68%.

  4. Short Time Cycles of Purely Quantum Refrigerators

    CERN Document Server

    Feldmann, Tova

    2012-01-01

    Four stroke Otto refrigerator cycles with no classical analogue are studied. Extremely short cycle times with respect to the internal time scale of the working medium characterize these refrigerators. Therefore these cycles are termed sudden. The sudden cycles are characterized by the stable limit cycle which is the invariant of the global cycle propagator. During their operation the state of the working medium possesses significant coherence which is not erased in the equilibration segments due to the very short time allocated. This characteristic is reflected in a difference between the energy entropy and the Von Neumann entropy of the working medium. A classification scheme for sudden refrigerators is developed allowing simple approximations for the cooling power and coefficient of performance.

  5. Nuclear reactors and fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    fulfill its mission that is to contribute in improving the quality of life of the Brazilian people. The nuclear fuel cycle is a series of steps involved in the production and use of fuel for nuclear reactors. The Laboratories of Chemistry and Environmental Diagnosis Center, CQMA, support the demand of Nuclear Fuel Cycle Program providing chemical characterization of uranium compounds and other related materials. In this period the Research Reactor Center (CRPq) concentrated efforts on improving equipment and systems to enable the IEA-R1 research reactor to operate at higher power, increasing the capacity of radioisotopes production, samples irradiation, tests and experiments. (author)

  6. Life cycle of transformer oil

    Directory of Open Access Journals (Sweden)

    Đurđević Ksenija R.

    2008-01-01

    Full Text Available The consumption of electric power is constantly increasing due to industrialization and population growth. This results in much more severe operating conditions of transformers, the most important electrical devices that make integral parts of power transmission and distribution systems. The designed operating life of the majority of worldwide transformers has already expired, which puts the increase of transformer reliability and operating life extension in the spotlight. Transformer oil plays a very important role in transformer operation, since it provides insulation and cooling, helps extinguishing sparks and dissolves gases formed during oil degradation. In addition to this, it also dissolves moisture and gases from cellulose insulation and atmosphere it is exposed to. Further and by no means less important functions of transformer are of diagnostic purpose. It has been determined that examination and inspection of insulation oil provide 70% of information on transformer condition, which can be divided in three main groups: dielectric condition, aged transformer condition and oil degradation condition. By inspecting and examining the application oil it is possible to determine the condition of insulation, oil and solid insulation (paper, as well as irregularities in transformer operation. All of the above-mentioned reasons and facts create ground for the subject of this research covering two stages of transformer oil life cycle: (1 proactive maintenance and monitoring of transformer oils in the course of utilization with reference to influence of transformer oil condition on paper insulation condition, as well as the condition of the transformer itself; (2 regeneration of transformer oils for the purpose of extension of utilization period and paper insulation revitalization potential by means of oil purification. The study highlights advantages of oil-paper insulation revitalization over oil replacement. Besides economic, there are

  7. Nuclear reactors and fuel cycle

    International Nuclear Information System (INIS)

    contribute in improving the quality of life of the Brazilian people. The nuclear fuel cycle is a series of steps involved in the production and use of fuel for nuclear reactors. The Laboratories of Chemistry and Environmental Diagnosis Center, CQMA, support the demand of Nuclear Fuel Cycle Program providing chemical characterization of uranium compounds and other related materials. In this period the Research Reactor Center (CRPq) concentrated efforts on improving equipment and systems to enable the IEA-R1 research reactor to operate at higher power, increasing the capacity of radioisotopes production, samples irradiation, tests and experiments. (author)

  8. Variants of closing the nuclear fuel cycle

    Science.gov (United States)

    Andrianova, E. A.; Davidenko, V. D.; Tsibulskiy, V. F.; Tsibulskiy, S. V.

    2015-12-01

    Influence of the nuclear energy structure, the conditions of fuel burnup, and accumulation of new fissile isotopes from the raw isotopes on the main parameters of a closed fuel cycle is considered. The effects of the breeding ratio, the cooling time of the spent fuel in the external fuel cycle, and the separation of the breeding area and the fissile isotope burning area on the parameters of the fuel cycle are analyzed.

  9. Epigenetic dynamics across the cell cycle

    DEFF Research Database (Denmark)

    Kheir, Tony Bou; Lund, Anders H.

    2010-01-01

    Progression of the mammalian cell cycle depends on correct timing and co-ordination of a series of events, which are managed by the cellular transcriptional machinery and epigenetic mechanisms governing genome accessibility. Epigenetic chromatin modifications are dynamic across the cell cycle...... a correct inheritance of epigenetic chromatin modifications to daughter cells. In this chapter, we summarize the current knowledge on the dynamics of epigenetic chromatin modifications during progression of the cell cycle....

  10. Empirical solar/stellar cycle simulations

    Directory of Open Access Journals (Sweden)

    Santos Ângela R. G.

    2015-01-01

    Full Text Available As a result of the magnetic cycle, the properties of the solar oscillations vary periodically. With the recent discovery of manifestations of activity cycles in the seismic data of other stars, the understanding of the different contributions to such variations becomes even more important. With this in mind, we built an empirical parameterised model able to reproduce the properties of the sunspot cycle. The resulting simulations can be used to estimate the magnetic-induced frequency shifts.

  11. Overview of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The nuclear fuel cycle is substantially more complicated than the energy production cycles of conventional fuels because of the very low abundance of uranium 235, the presence of radioactivity, the potential for producing fissile nuclides from irradiation, and the risk that fissile materials will be used for nuclear weapons. These factors add enrichment, recycling, spent fuel storage, and safeguards to the cycle, besides making the conventional steps of exploration, mining, processing, use, waste disposal, and transportation more difficult

  12. The spatial dimension of cycle logistics

    OpenAIRE

    Vitale Brovarone, Elisabetta; Staricco, Luca

    2016-01-01

    Cycle logistics is emerging as a promising alternative in urban freight transport. Compared to fossil fuelled vans, the use of cycles for delivering goods within urban areas offers advantages in terms of environmental friendliness, economic efficiency, flexibility, and liveability of urban neighbourhood. At the same time, cycle logistics has to face limits in terms of weight and volume of goods that can be delivered, distances that can be covered, and spatial urban structures that can be serv...

  13. Should We Rely on Intelligence Cycle?

    OpenAIRE

    Aydın, Bahadir; Ozleblebici, Zafer

    2015-01-01

    Intelligence cycle is a systematic process which is usually applied in order to obtain intelligence from raw data. Today the world has been experiencing dazzling changes on many fields as well as technology. With the help of the new emerging technologies the data that have to be handled for intelligence is much more than ever. In addition to new technological contributions, there are discussions about intelligence cycle whether it’s being out-dated and old fashioned. Intelligence cycle was ma...

  14. The Frequency Analysis of the Business Cycle

    OpenAIRE

    Prof D.S.G. Pollock

    2008-01-01

    An account is given of some techniques of linear filtering that can be used for extracting the business cycle from economic data sequences of limited duration. It is argued that there can be no definitive definition of the business cycle. Both the definition of the business cycle and the methods that are used to extract it must be adapted to the purposes of the analysis; and different definitions may be appropriate to different eras.

  15. Limit Cycle Oscillations in Pacemaker Cells

    CERN Document Server

    Endresen, L P; Endresen, Lars Petter; Skarland, Nils

    1999-01-01

    In recent decades, several mathematical models describing the pacemaker activity of the rabbit sinoatrial node have been developed. We demonstrate that it is not possible to establish the existence, uniqueness, and stability of a limit cycle oscillation in those models. Instead we observe an infinite number of limit cycles. We then display numerical results from a new model, with a limit cycle that can be reached from many different initial conditions.

  16. The sulfur cycle in the marine atmosphere

    Science.gov (United States)

    Toon, Owen B.; Kasting, James F.; Turco, Richard P.; Liu, May S.

    1987-01-01

    The simulation of the sulfur cycle in the marine atmosphere using a one-dimensional photochemical model is described and evaluated. Theoretical uncertainties concerning the operation of the marine sulfur cycle are examined, and measurements of sulfur gases in the marine atmosphere necessary for developing the model are derived. Previous modeling studies are reviewed, and the data from these studies are compared to the model simulations. Recommendations for improving the simulation of the sulfur cycle in the marine atmosphere are discussed.

  17. Open cycle cooling systems using solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Sovrano, M.

    Open cycle cooling systems are particularly suitable for utilizing solar energy. In all these systems the adsorption and absorption phenomena are very important, hence they are described separately. The cycles used are essentially two: the Baum-Kakabaev cycle using liquid absorbers and the dehumidification/humidification cycle where also adsorbent substances can be utilized. Solar energy is used in the regeneration process of dehumidifying substances. Reactivation modes can be various: suitability of one mode or the other can depend on the climate of the site where the system is installed.

  18. Supermarket Defrost Cycles As Flexible Reserve

    DEFF Research Database (Denmark)

    Pedersen, Rasmus; Sloth, Christoffer; Wisniewski, Rafal;

    2015-01-01

    This work analyses how supermarket defrost cycles can be used as flexible reserve in a smart grid context. The consumption flexibility originates from being able to shift defrost cycles in time, while adhering to the underlying refrigeration systems constraints. It is shown how this time constrai......This work analyses how supermarket defrost cycles can be used as flexible reserve in a smart grid context. The consumption flexibility originates from being able to shift defrost cycles in time, while adhering to the underlying refrigeration systems constraints. It is shown how this time...

  19. Reproductive cycle of dogs and artificial insemination

    OpenAIRE

    Zvolská, Helena

    2012-01-01

    The first sexual cycle of a bitch begins in the period of pubescence, approximately between 6th and 24th month of life. Considering breed and individuality, estrus is repeated mostly twice a year. The whole cycle is divided into 4 stadiums: proestrus (5 – 20 days), estrus (3 – 21 days), metestrus (diestrus, 50-80 days) and anestrus (80 – 240 days). The cycle is initiated due to the evaluation of inner and extinor impulses by the central nervous system. In the first stadium of the cycle, ...

  20. Probable Values of Current Solar Cycle Peak

    Directory of Open Access Journals (Sweden)

    V. M. Silbergleit

    2012-01-01

    Full Text Available An analysis of multiple linear regression method applied to solar cycles 4 to 23 using lagged values of smoothed monthly mean sunspot numbers as independent variables is presented. According to that, the amplitude of current solar cycle 24 is estimated providing a quantitative prediction result. Our adjustment shows that the current cycle would have a sunspot peak less than the biggest one observed during the cycle 19 giving an additional support to the declination in solar activity which is currently happening.

  1. Combined rankine and vapor compression cycles

    Science.gov (United States)

    Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

    2005-04-19

    An organic rankine cycle system is combined with a vapor compression cycle system with the turbine generator of the organic rankine cycle generating the power necessary to operate the motor of the refrigerant compressor. The vapor compression cycle is applied with its evaporator cooling the inlet air into a gas turbine, and the organic rankine cycle is applied to receive heat from a gas turbine exhaust to heat its boiler within one embodiment, a common condenser is used for the organic rankine cycle and the vapor compression cycle, with a common refrigerant, R-245a being circulated within both systems. In another embodiment, the turbine driven generator has a common shaft connected to the compressor to thereby eliminate the need for a separate motor to drive the compressor. In another embodiment, an organic rankine cycle system is applied to an internal combustion engine to cool the fluids thereof, and the turbo charged air is cooled first by the organic rankine cycle system and then by an air conditioner prior to passing into the intake of the engine.

  2. Aromatase inhibitors in stimulated IVF cycles

    DEFF Research Database (Denmark)

    Papanikolaou, Evangelos G; Polyzos, Nikolaos P; Al Humaidan, Peter Samir Heskjær;

    2011-01-01

    are available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears...... to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels....

  3. Economic aspects of Dukovany NPP fuel cycle

    International Nuclear Information System (INIS)

    The paper discusses some aspects of high burnup program implementation at Dukovany NPP and its influence on the fuel cycle costs. Dukovany internal fuel cycle is originally designed as a three years cycle of the Out-In-In fuel reloading patterns. These reloads are not only uneconomical but they additionally increased the radiation load of the reactor pressure vessel due to high neutron leakage typical for Out-In-In loading pattern. To avoid the high neutron leakage from the core a transition to 4-year fuel cycle is started in 1987. The neutron leakage from the core is sequentially decreased by insertion of older fuel assemblies at the core periphery. Other developments in fuel cycle are: 1) increasing of enrichment in control assemblies (3.6% of U-235); 2) improvement in fuel assembly design (reduce the assembly shroud thickness from 2.1 to 1.6 mm); 3) introduction of Zr spacer grid instead of stainless steel; 4) introduction of new type of assembly with profiled enrichment with average value of 3.82%. Due to increased reactivity of the new assemblies the transition to the partial 5-year fuel cycle is required. Typical fuel loading pattern for 3, 3.5, 4 and 5-year cycles are shown in the presented paper. An evaluation of fuel cost is also discussed by using comparative analysis of different fuel cycle options. The analysis shows that introduction of the high burnup program has decrease relative fuel cycle costs

  4. Nonlinear solar cycle forecasting: theory and perspectives

    Directory of Open Access Journals (Sweden)

    A. L. Baranovski

    2008-02-01

    Full Text Available In this paper we develop a modern approach to solar cycle forecasting, based on the mathematical theory of nonlinear dynamics. We start from the design of a static curve fitting model for the experimental yearly sunspot number series, over a time scale of 306 years, starting from year 1700 and we establish a least-squares optimal pulse shape of a solar cycle. The cycle-to-cycle evolution of the parameters of the cycle shape displays different patterns, such as a Gleissberg cycle and a strong anomaly in the cycle evolution during the Dalton minimum. In a second step, we extract a chaotic mapping for the successive values of one of the key model parameters – the rate of the exponential growth-decrease of the solar activity during the n-th cycle. We examine piece-wise linear techniques for the approximation of the derived mapping and we provide its probabilistic analysis: calculation of the invariant distribution and autocorrelation function. We find analytical relationships for the sunspot maxima and minima, as well as their occurrence times, as functions of chaotic values of the above parameter. Based on a Lyapunov spectrum analysis of the embedded mapping, we finally establish a horizon of predictability for the method, which allows us to give the most probable forecasting of the upcoming solar cycle 24, with an expected peak height of 93±21 occurring in 2011/2012.

  5. Rotary Stirling-Cycle Engine And Generator

    Science.gov (United States)

    Chandler, Joseph A.

    1990-01-01

    Proposed electric-power generator comprises three motor generators coordinated by microprocessor and driven by rotary Stirling-cycle heat engine. Combination offers thermodynamic efficiency of Stirling cycle, relatively low vibration, and automatic adjustment of operating parameters to suit changing load on generator. Rotary Stirling cycle engine converts heat to power via compression and expansion of working gas between three pairs of rotary pistons on three concentric shafts in phased motion. Three motor/generators each connected to one of concentric shafts, can alternately move and be moved by pistons. Microprocessor coordinates their operation, including switching between motor and generator modes at appropriate times during each cycle.

  6. Cycle slipping in phase synchronization systems

    Science.gov (United States)

    Yang, Ying; Huang, Lin

    2007-02-01

    Cycle slipping is a characteristically nonlinear phenomenon in phase synchronization systems, which is highly dependent of the initial state of the system. Slipping a cycle means that the phase error is increased to such an extent that the generator to be synchronized slips one complete cycle with respect to the input phase. In this Letter, a linear matrix inequality (LMI) based approach is proposed and the estimation of the number of cycles which slips a solution of the system is obtained by solving a quasi-convex optimization problem of LMI. Applications to phase locked loops demonstrate the validity of the proposed approach.

  7. Kalina cycle. Thermodynamic principles and feasibility

    Energy Technology Data Exchange (ETDEWEB)

    Gajewski, W.; Lezuo, A.; Nuernberg, R.; Rukes, B.; Vesper, H.

    1989-05-01

    The Kalina cycle belongs to the group of absorption cycles. It is operated with the two substances H/sub 2/O/NH/sub 3/. For combined gas- and steam power plants using the Kalina retrofit cycle in place of the normal water/steam cycle an increase in efficiency by about 2 to 3 percentage points can be expected. The advantage in efficiency contrasts with the high additional expenditure in capital costs. In addition operating difficulties as a result of partial decomposition of the ammonia are to be expected.

  8. Entering the German Gas market in Lübeck

    OpenAIRE

    Amith, Azmi; Finstad, Kenneth; Lie, Geir Andre

    2009-01-01

    Gasnor AS is a Norwegian Gas company consisting of 50 employees. Gasnor is characterizing Norway as its main market, with their main activities on the west side of Norway, where they have their main office. Nowadays they are considering expansion to the German market, but they already have some international activities, delivering gas to parts of England and Sweden. Since Gasnor are planning on expansion to Germany they have asked us to make a market research for them, and t...

  9. Kaksikud lahendavad geneetilised mõistatused / Rasmus Thirup Beck

    Index Scriptorium Estoniae

    Beck, Rasmus Thirup

    2015-01-01

    Maailma ainsate astronautidest ühemunarakukaksikute Mark ja Scott Kellyga tehtud katsete ajal tehakse kindlaks, kuidas reageerib inimese organism pikaajalisele viibimisele kosmosekeskkonnas. Ka teistest kaksikute uuringutest

  10. Maakoolid ja koduõpe Norras / Christian W. Beck

    Index Scriptorium Estoniae

    Beck, Christian W.

    2007-01-01

    Tänapäevane koduõpe sai Norras alguse aastatel 1991-1994. Aastail 1997-2004 püüdis meedia tähelepanu väikeste koolide sulgemine maarajoonides. Rahvas tahtis aga, et nende kodukohas oleks kool, ning kasutas oma õigust taotleda vabakooli. Avalduse käsitlemise ajal õpetasid vanemad lapsi kodus. Kohalikud koolivõimud püüdsid vanemaid takistada. Aktsiooni tulemuseks oli uut tüüpi külakoolide rajamine. Koduõpe kui väikekoolide ellujäämisstrateegia

  11. Avalik kiri Euroopa tulevikust / Anthony Giddens, Ulrich Beck

    Index Scriptorium Estoniae

    Giddens, Anthony

    2005-01-01

    Autorid kutsuvad üles mõtlema Euroopa Liidust mitte kui "lõpetamata (rahvus)riigist" või "poolikust föderaalriigist", vaid pigem kui uuelaadsest kosmopoliitsest projektist. Kui Euroopa soovib, et teda maailmas kuulda võetaks, siis ei saa me deklareerida laienemise lõppemist ega loobuda EL-i juhtimismudeli muutmisest

  12. Globalisation, Environmental Degradation and Ulrich Beck's Risk Society

    OpenAIRE

    Brent K. Marshall

    1999-01-01

    This paper is organised in three interconnected parts. First, contemporary political economic approaches to understanding the structure of the global economic system are outlined and synthesised. Specifically, it is suggested that the current structural configuration of the globe is a transitional phase between the spatially-bounded configuration hypothesised by world-system theory and the configuration hypothesised by globalisation theorists. Second, the contemporary problem of environmental...

  13. Radioecology of nuclear fuel cycles

    International Nuclear Information System (INIS)

    Sites where radioactive wastes are found are solid waste burial grounds, soils below liquid stoage areas, surface ditches and ponds, and the terrestrial environment around chemical processing facilities that discharge airborne radioactive debris from stacks. This study provides information to help assess the environmental impacts and certain potentiall human hazards associated with nuclear fuel cycles. A data base is being developed to define and quantify biological transport routes which will permit credible predictions and assessment of routine and potential large-scale releases of radionuclides and other toxic materials. These data, used in assessment models, will increase the accuracy of estimating radiation doses to man and other life forms. Information obtained from existing storage and disposal sites will provide a meaningful radioecological perspective with which to improve the effectiveness of waste management practices. Results will provide information to determine if waste management procedures on the Hanford Site have caused ecological perturbations, and if so, to determine the source, nature, and magnitude of such disturbances

  14. Mercury cycling in terrestrial watersheds

    Science.gov (United States)

    Shanley, James B.; Bishop, Kevin; Banks, Michael S.

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  15. MHD Integrated Topping Cycle Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    This fourteenth quarterly technical progress report of the MHD Integrated Topping Cycle Project presents the accomplishments during the period November 1, 1990 to January 31, 1991. Testing of the High Pressure Cooling Subsystem electrical isolator was completed. The PEEK material successfully passed the high temperature, high pressure duration tests (50 hours). The Combustion Subsystem drawings were CADAM released. The procurement process is in progress. An equipment specification and RFP were prepared for the new Low Pressure Cooling System (LPCS) and released for quotation. Work has been conducted on confirmation tests leading to final gas-side designs and studies to assist in channel fabrication.The final cathode gas-side design and the proposed gas-side designs of the anode and sidewall are presented. Anode confirmation tests and related analyses of anode wear mechanisms used in the selection of the proposed anode design are presented. Sidewall confirmation tests, which were used to select the proposed gas-side design, were conducted. The design for the full scale CDIF system was completed. A test program was initiated to investigate the practicality of using Avco current controls for current consolidation in the power takeoff (PTO) regions and to determine the cause of past current consolidation failures. Another important activity was the installation of 1A4-style coupons in the 1A1 channel. A description of the coupons and their location with 1A1 channel is presented herein.

  16. Production cycles in aquatic microcosms

    Energy Technology Data Exchange (ETDEWEB)

    Jassby, A.; Dudzik, M.; Rees, J.; Lapan, E.; Levy, D.; Harte, J.

    1977-02-08

    Four 700-liter cylindrical containers were filled with demineralized water, enriched with nutrients, and inoculated with 3.5-liter lakewater samples. The microcosms were maintained at a temperature of 18/sup 0/C under a 12:12 L:D cycle for 6 months and several manipulations of their trophic structure were carried out, including addition of snails (Physa sp.), mosquitofish (Gambusia affinis), and catfish (Placostomas placostomas). Temporal variation of the phytoplankton resembled the bimodal patterns of certain natural systems. Further analysis demonstrated a close analogy with the predator-prey oscillations of temperate marine waters: an initial bloom is terminated by zooplankton grazing; the resulting low phytoplankton levels lead to gradual starvation of the zooplankton; and a second bloom follows the final dieoff of zooplankton. Both decreasing the concentration of initial nutrients and stocking the microcosms with Gambusia decreases the time between the spring and fall blooms. The problem of heavy periphyton growth in microcosms was not solved with the introduction of either Physa or Placostomas. Possible solutions to this and to other problems peculiar to microcosm research are discussed, and modifications are suggested for increasing the ability of microcosms to simulate natural systems.

  17. Exergoeconomic comparison of TLC (trilateral Rankine cycle), ORC (organic Rankine cycle) and Kalina cycle using a low grade heat source

    International Nuclear Information System (INIS)

    Recently, the TLC (trilateral power cycle) has attracted significant interest as it provides better matching between the temperature profiles in the evaporator compared to conventional power cycles. This article investigates the performance of this cycle and compares it with those for the ORC (organic Rankine cycle) and the Kalina cycle, from the viewpoints of thermodynamics and thermoeconomics. A low-grade heat source with a temperature of 120 °C is considered for all the three systems. Parametric studies are performed for the systems for several working fluids in the ORC and TLC. The systems are then optimized for either maximum net output power or minimum product cost, using the EES (engineering equation solver) software. The results for the TLC indicate that an increase in the expander inlet temperature leads to an increase in net output power and a decrease in product cost for this power plant, whereas this is not the case for the ORC system. It is found that, although the TLC can achieve a higher net output power compared with the ORC and Kalina (KCS11 (Kalina cycle system 11)) systems, its product cost is greatly affected by the expander isentropic efficiency. It is also revealed that using n-butane as the working fluid can result in the lowest product cost in the ORC and the TLC. In addition, it is observed that, for both the ORC and Kalina systems, the optimum operating condition for maximum net output power differs from that for minimum product cost. - Highlights: • Exergoeconomic analysis of trilateral Rankine cycle is performed. • The system performance is compared with Organic Rankine and Kalina cycles. • Net power from trilateral Rankine cycle is higher than the other power systems. • Superiority of trilateral cycle depends on its expander isentropic efficiency

  18. Science Illiteracy: Breaking the Cycle

    Science.gov (United States)

    Lebofsky, L. A.; Lebofsky, N. R.

    2003-12-01

    At the University of Arizona, as at many state universities and colleges, the introductory science classes for non-science majors may be the only science classes that future K--8 teachers will take. The design of the UA's General Education program requires all future non-science certified teachers to take the General Education science classes. These classes are therefore an ideal venue for the training of the state's future teachers. Many students, often including future teachers, are ill-prepared for college, i.e., they lack basic science content knowledge, basic mathematics skills, and reading and writing skills. They also lack basic critical thinking skills and study skills. It is within this context that our future teachers are trained. How do we break the cycle of science illiteracy? There is no simple solution, and certainly not a one-size-fits-all panacea that complements every professor's style of instruction. However, there are several programs at the University of Arizona, and also principles that I apply in my own classes, that may be adaptable in other classrooms. Assessment of K--12 students' learning supports the use of inquiry-based science instruction. This approach can be incorporated in college classes. Modeling proven and productive teaching methods for the future teachers provides far more than ``just the facts,'' and all students gain from the inquiry approach. Providing authentic research opportunities employs an inquiry-based approach. Reading (outside the textbook) and writing provide feedback to students with poor writing and critical thinking skills. Using peer tutors and an instant messaging hot line gives experience to the tutors and offers "comfortable" assistance to students.

  19. Nature's third cycle a story of sunspots

    CERN Document Server

    Choudhuri, Arnab Rai

    2015-01-01

    The cycle of day and night and the cycle of seasons are two familiar natural cycles around which many human activities are organized. But is there a third natural cycle of importance for us humans? On 13 March 1989, six million people in Canada went without electricity for many hours: a large explosion on the sun was discovered as the cause of this blackout. Such explosions occur above sunspots, dark features on the surface of the Sun that have been observed through telescopes since the time of Galileo. The number of sunspots has been found to wax and wane over a period of 11 years. Although this cycle was discovered less than two centuries ago, it is becoming increasingly important for us as human society becomes more dependent on technology. For nearly a century after its discovery, the cause of the sunspot cycle remained completely shrouded in mystery. The 1908 discovery of strong magnetic fields in sunspots made it clear that the 11-year cycle is the magnetic cycle of the sun. It is only during the last ...

  20. Finite Feedback Cycling in Structural Equation Models

    Science.gov (United States)

    Hayduk, Leslie A.

    2009-01-01

    In models containing reciprocal effects, or longer causal loops, the usual effect estimates assume that any effect touching a loop initiates an infinite cycling of effects around that loop. The real world, in contrast, might permit only finite feedback cycles. I use a simple hypothetical model to demonstrate that if the world permits only a few…

  1. Ocular biometric characteristics during the menstrual cycle

    Directory of Open Access Journals (Sweden)

    Çakmak H

    2015-06-01

    Full Text Available Harun Çakmak,1 Ayten Taspinar,2 Mehmet Ozbagcivan,1 Tolga Kocatürk1 1Department of Ophthalmology, 2Department of Midwifery, School of Health, Adnan Menderes University Medical Faculty, Aydin, Turkey Purpose: To determine the ocular biometric characteristics during the menstrual cycle using the optical low-coherence reflectometry (OLCR biometry. Methods: Twenty-two healthy women between the ages of 19 and 36 years with regular menstrual cycles were enrolled in this prospective study. Subjects with irregular menstrual cycles, those taking contraceptive pills, those with a history of ocular surgery or trauma, and women unable to cooperate with the ocular biometry device were excluded from this study. A complete ophthalmic examination was performed between 8.30 and 10.30 am for all participants. Also, central corneal thickness, axial length, anterior chamber depth, lens thickness, and keratometric measurements were made at the same time using the OLCR device. Measurements were taken at the beginning of the cycle (1–3 days, at ovulation (12–16 days, and at the end of the cycle (26–32 days. Results: The mean age of the participants was 22.86±4.22 (range: 18–36 years. The difference in central corneal thickness, axial length, anterior chamber depth, lens thickness, and keratometry values were not statistically significant during the menstrual cycle. Conclusion: The ocular biometric parameters did not significantly vary during the menstrual cycle according to the OLCR biometry. Keywords: ocular biometry, OLCR, menstrual cycle

  2. The Experiential Learning Cycle in Visual Design

    Science.gov (United States)

    Arsoy, Aysu; Özad, Bahire Efe

    2004-01-01

    Experiential Learning Cycle has been applied to the Layout and Graphics Design in Computer Course provided by the Faculty of Communication and Media Studies to the students studying at the Public Relations and Advertising Department. It is hoped that by applying the Experiential Learning Cycle, the creativity and problem solving strategies of the…

  3. The Brain-Mind Cycle of Reflection.

    Science.gov (United States)

    Iran-Nejad, Asghar; Gregg, Madeleine

    2001-01-01

    Discusses a theory of thinking, learning, and schooling based on developments in biofunctional cognition and the notion that the brain-awareness-mind cycle directly represents the natural course of human reflection. The paper argues that what makes this brain-mind cycle of reflection possible is intuitive self-awareness. Data from an experimental…

  4. Integrating hospital and physician revenue cycle operations.

    Science.gov (United States)

    Lockett, Kevin M

    2014-03-01

    Standardized revenue cycle processes should be a key component of the coordinated care delivery strategy organizations will require to complete the transition to population health management. Integrating hospital and physician revenue cycle operations can help organizations better navigate new payment models, reduce costs, and improve value. The most comprehensive approach involves integrating patient access and registration, coding operations, and receivables management across different settings.

  5. Magnetic cycles at different ages of stars

    Science.gov (United States)

    Oláh, K.; Kővári, Zs.; Petrovay, K.; Soon, W.; Baliunas, S.; Kolláth, Z.; Vida, K.

    2016-06-01

    Aims: We study the different patterns of interannual magnetic variability in stars on or near the lower main sequence, approximately solar-type (G-K dwarf) stars in time series of 36 yr from the Mount Wilson Observatory Ca ii H&K survey. Our main aim is to search for correlations between cycles, activity measures, and ages. Methods: Time-frequency analysis has been used to discern and reveal patterns and morphology of stellar activity cycles, including multiple and changing cycles, in the datasets. Both the results from short-term Fourier transform and its refinement using the Choi-Williams distribution, with better frequency resolution, are presented in this study. Rotational periods of the stars were derived using multifrequency Fourier analysis. Results: We found at least one activity cycle on 28 of the 29 stars we studied. Twelve stars, with longer rotational periods (39.7 ± 6.0 days), have simple smooth cycles, and the remaining stars, with much faster rotation (18.1 ± 12.2 days) on average, show complex and sometimes vigorously changing multiple cycles. The cycles are longer and quite uniform in the first group (9.7 ± 1.9 yr), while they are generally shorter and vary more strongly in the second group (7.6 ± 4.9). The clear age division between stars with smooth and complex cycles follows the known separation between the older and younger stars at around 2 to 3 Gyr of age.

  6. An Ethnography of the Navajo Reproductive Cycle.

    Science.gov (United States)

    Wright, Anne

    1982-01-01

    Describes the reproductive cycle (menarche, menstrual cycle, fertility and contraceptive use, and menopause) as experienced by two groups of contemporary Navajo women. Eighty Navajo women, 40 traditional and 40 acculturated, participated in the 1978 research project which focused on influences of menopause. (ERB)

  7. LIFE CYCLE ASSESSMENT: PRINCIPLES AND PRACTICE

    Science.gov (United States)

    The following document provides an introductory overview of Life Cycle Assessment (LCA) and describes the general uses and major components of LCA. This document is an update and merger of two previous EPA documents on LCA ("Life Cycle Assessment: Inventory Guidelines and Princip...

  8. How people with low vision cycle safely

    NARCIS (Netherlands)

    Jelijs, Bart; Melis-Dankers, Bart; de Waard, Dick; Heutink, Jochem

    2015-01-01

    In the Netherlands, the ability to cycle safely and responsibly is important for independent mobility across the lifespan. In addition, cycling can be important in maintaining physical health. But when can a visually challenged person use a bicycle safely? Opinions vary, but there are no reliable -

  9. Uncertainty Analyses of Advanced Fuel Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Laurence F. Miller; J. Preston; G. Sweder; T. Anderson; S. Janson; M. Humberstone; J. MConn; J. Clark

    2008-12-12

    The Department of Energy is developing technology, experimental protocols, computational methods, systems analysis software, and many other capabilities in order to advance the nuclear power infrastructure through the Advanced Fuel Cycle Initiative (AFDI). Our project, is intended to facilitate will-informed decision making for the selection of fuel cycle options and facilities for development.

  10. Survey of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    A brief outline of the technical aspects of the fuel cycle, starting from the mining of uranium up to fuel element fabrication, is followed by a more detailed description of the management of the outer fuel cycle. This includes the system of contracts and their reciprocal technical and chronological interdepence, as well as financial aspects, market conditions and trends. (RB)

  11. Khovanov-Rozansky homology and Directed Cycles

    OpenAIRE

    Wu, Hao

    2015-01-01

    We determine the cycle packing number of a directed graph using elementary projective algebraic geometry. Our idea is rooted in the Khovanov-Rozansky theory. In fact, using the Khovanov-Rozansky homology of a graph, we also obtain algebraic methods of detecting directed and undirected cycles containing a particular vertex or edge.

  12. Physics challenges for advanced fuel cycle assessment

    Energy Technology Data Exchange (ETDEWEB)

    Giuseppe Palmiotti; Massimo Salvatores; Gerardo Aliberti

    2014-06-01

    Advanced fuel cycles and associated optimized reactor designs will require substantial improvements in key research area to meet new and more challenging requirements. The present paper reviews challenges and issues in the field of reactor and fuel cycle physics. Typical examples are discussed with, in some cases, original results.

  13. Analysis of the Schizosaccharomyces pombe Cell Cycle.

    Science.gov (United States)

    Hagan, Iain M; Grallert, Agnes; Simanis, Viesturs

    2016-01-01

    Schizosaccharomyces pombe cells are rod shaped, and they grow by tip elongation. Growth ceases during mitosis and cell division; therefore, the length of a septated cell is a direct measure of the timing of mitotic commitment, and the length of a wild-type cell is an indicator of its position in the cell cycle. A large number of documented stage-specific changes can be used as landmarks to characterize cell cycle progression under specific experimental conditions. Conditional mutations can permanently or transiently block the cell cycle at almost any stage. Large, synchronously dividing cell populations, essential for the biochemical analysis of cell cycle events, can be generated by induction synchrony (arrest-release of a cell cycle mutant) or selection synchrony (centrifugal elutriation or lactose-gradient centrifugation). Schizosaccharomyces pombe cell cycle studies routinely combine particular markers, mutants, and synchronization procedures to manipulate the cycle. We describe these techniques and list key landmarks in the fission yeast mitotic cell division cycle. PMID:27587785

  14. Cycle-maximal triangle-free graphs

    DEFF Research Database (Denmark)

    Durocher, Stephane; Gunderson, David S.; Li, Pak Ching;

    2015-01-01

    Abstract We conjecture that the balanced complete bipartite graph K ⌊ n / 2 ⌋ , ⌈ n / 2 ⌉ contains more cycles than any other n -vertex triangle-free graph, and we make some progress toward proving this. We give equivalent conditions for cycle-maximal triangle-free graphs; show bounds...

  15. Uncertainty Analyses of Advanced Fuel Cycles

    International Nuclear Information System (INIS)

    The Department of Energy is developing technology, experimental protocols, computational methods, systems analysis software, and many other capabilities in order to advance the nuclear power infrastructure through the Advanced Fuel Cycle Initiative (AFDI). Our project, is intended to facilitate will-informed decision making for the selection of fuel cycle options and facilities for development

  16. Fuel cycles for the 80's

    International Nuclear Information System (INIS)

    Papers presented at the American Nuclear Society's topical meeting on the fuel cycle are summarized. Present progress and goals in the areas of fuel fabrication, fuel reprocessing, spent fuel storage, accountability, and safeguards are reported. Present governmental policies which affect the fuel cycle are also discussed. Individual presentations are processed for inclusion in the Energy Data Base

  17. General framework for bridge life cycle design

    Institute of Scientific and Technical Information of China (English)

    Junhai MA; Airong CHEN; Jun HE

    2009-01-01

    Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environ-mental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.

  18. Possible types of breeders with thorium cycle

    International Nuclear Information System (INIS)

    Neutronics calculations of simplified homogeneous reactor models show the possibility that metal-fueled LMFBRs and coated particle fueled gas cooled reactors achieve reactor doubling times of around 10 years with the thorium cycle. Three concepts of gas-cooled thorium cycle breeders are discused. (Author)

  19. Possible types of breeders with thorium cycle

    International Nuclear Information System (INIS)

    Neutronics calculations of simplified homogeneous reactor models show the possibility that metal-fueled LMFBRs and coated particle fueled gas cooled reactors achieve doubling times of around 10 years with the thorium cycle. Three concepts of gas-cooled thorium cycle breeders are discussed. (Author)

  20. Helioseismic Solar Cycle Changes and Splitting Coefficients

    Indian Academy of Sciences (India)

    S. C. Tripathy; Kiran Jain; A. Bhatnagar

    2000-09-01

    Using the GONG data for a period over four years, we have studied the variation of frequencies and splitting coefficients with solar cycle. Frequencies and even-order coefficients are found to change significantly with rising phase of the solar cycle. We also find temporal variations in the rotation rate near the solar surface.

  1. Few-optical-cycle dissipative solitons

    Energy Technology Data Exchange (ETDEWEB)

    Leblond, H [Laboratoire de Photonique d' Angers EA 4464, Universite d' Angers, 2 Bd. Lavoisier, 49045 Angers Cedex 01 (France); Mihalache, D, E-mail: herve.leblond@univ-angers.f [Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), 407 Atomistilor, Magurele-Bucharest, 077125 (Romania)

    2010-09-17

    By using a powerful reductive perturbation technique, or multiscale analysis, a generalized modified Korteweg-de Vries partial differential equation is derived, which describes the physics of few-optical-cycle dissipative solitons beyond the slowly varying envelope approximation. Numerical simulations of the formation of stable dissipative solitons from arbitrary breather-like few-cycle pulses are also given.

  2. Effective risk management SOGO life cycle management

    OpenAIRE

    Ali, Mohamed Omar

    2012-01-01

    After new or upgrade projects the offshore installation gets maintenance or support through the life cycle management organization at Siemens. Small to medium modification projects are executed by the life cycle management. Risk assessment on these projects show different risks when it comes to estimation and pricing of projects, planning and executing, resource management, competence and knowledge.

  3. Advanced fuel cycles: a rationale and strategy for adopting the low-enriched-uranium fuel cycle

    International Nuclear Information System (INIS)

    A two-year study of alternatives to the natural uranium fuel cycle in CANDU reactors is summarized. The possible advanced cycles are briefly described. Selection criteria for choosing a cycle for development include resource utilization, economics, ease of implementaton, and social acceptability. It is recommended that a detailed study should be made with a view to the early implementation of the low-enriched uranium cycle. (LL)

  4. Verification of a Similar Cycle Prediction for the Ascending and Peak Phases of Solar Cycle 23

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Reviews of long-term predictions of solar cycles have shown that a precise prediction with a lead time of 2 years or more of a solar cycle remains an unsolved problem. We used a simple method, the method of similar cycles, to make long-term predictions of not only the maximum amplitude but also the smoothed monthly mean sunspot number for every month of Solar Cycle 23. We verify and compare our prediction with the latest available observational results.

  5. Associations between urban form and cycling

    DEFF Research Database (Denmark)

    Nielsen, Thomas Alexander Sick; Olafsson, Anton Stahl; Carstensen, Trine Agervig

    The bikeability project has analysed the environmental correlates of cycling based on Danish National Transportation Survey data transportation and urban form micro-data; and based on a smaller sample of primary data which included housing preferences, policy and attitude variables. Analysis...... of National Travel Survey data indicated that established walkability factors such as density, connectivity and diversity are related to cycling, and that access to retail concentrations/centres, public transportation level-of-service, as well as competition between walking and cycling depending...... on environmental features can be added to the set of influential environmental factors. Attractive conditions for using public transportation or walking are related to less cycling. Highly relevant in the context of the promotion of cycling, the results suggest different effects of urban form on the probability...

  6. Cycles and Clustering in Multiplex Networks

    CERN Document Server

    Baxter, Gareth J; Dorogovtsev, Sergey N; Mendes, José F F

    2016-01-01

    In multiplex networks, cycles cannot be characterized only by their length, as edges may occur in different layers in different combinations. We define a classification of cycles by the number of edges in each layer and the number of switches between layers. We calculate the expected number of cycles of each type in the configuration model of a large sparse multiplex network. Our method accounts for the full degree distribution including correlations between degrees in different layers. In particular, we obtain the numbers of cycles of length 3 of all possible types. Using these, we give a complete set of clustering coefficients and their expected values. We show that correlations between the degrees of a vertex in different layers strongly affect the number of cycles of a given type, and the number of switches between layers. Both increase with assortative correlations and are strongly decreased by disassortative correlations. The effect of correlations on clustering coefficients is equally pronounced.

  7. Life cycle assessment of fertilizers: a review

    Science.gov (United States)

    Skowrońska, Monika; Filipek, Tadeusz

    2014-03-01

    Life cycle assessment has become an increasingly common approach for identifying, quantifying, and evaluating the total potential environmental impact of production processes or products, from the procurement of raw materials (the `cradle'), to production and utilization (the `gates') and their final storage (the `grave'), as well as for determining ways to repair damage to the environment. The paper describes life cycle assessment of mineral fertilizers. On the basis of results provided by life cycle assessment, it can be concluded that an effective strategy for protecting the environment against the harmful effects of fertilizers is to attempt to `seal' the nutrient cycle on a global, regional, and local scale. Pro-environ- mental measures aim on the one hand to reduce resource utilization, and on the other hand to limit losses of nutrients, during both production and use of fertilizers. An undoubted challenge for life cycle assessment when used in agricultural production is the need for relevance at each scale.

  8. Low cycle fatigue problem in RAPP fuel

    International Nuclear Information System (INIS)

    In a nuclear power plant, the fuel sheath is subjected to power cycling during start-up and shut-down, and also during normal operation. Power reactors operating in relatively small electrical grids, as for example RAPS-1 are prone to large number of such power cycles. RAPS fuel sheath being of the collapsible design is subjected to high initial plastic strains. These environmental conditions pose serious low cycle fatigue problem in RAPS fuel operations. The limitations on fuel life due to low cycle fatigue are described. The low cycle fatigue behaviour of zircaloy under normal and irradiation is discussed. UO2 expansion model used for calculating plastic strains is also described. (author)

  9. Thorium fuel cycle - Potential benefits and challenges

    International Nuclear Information System (INIS)

    There has been significant interest among Member States in developing advanced and innovative technologies for safe, proliferation resistant and economically efficient nuclear fuel cycles, while minimizing waste and environmental impacts. This publication provides an insight into the reasons for renewed interest in the thorium fuel cycle, different implementation scenarios and options for the thorium cycle and an update of the information base on thorium fuels and fuel cycles. The present TECDOC focuses on the upcoming thorium based reactors, current information base, front and back end issues, including manufacturing and reprocessing of thorium fuels and waste management, proliferation-resistance and economic issues. The concluding chapter summarizes future prospects and recommendations pertaining to thorium fuels and fuel cycles

  10. Plutonium in an enduring fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Pillay, K.K.S.

    1998-05-01

    Nuclear fuel cycles evolved over the past five decades have allowed many nations of the world to enjoy the benefits of nuclear energy, while contributing to the sustainable consumption of the world`s energy resources. The nuclear fuel cycle for energy production suffered many traumas since the 1970s because of perceived risks of proliferation of nuclear weapons. However, the experience of the past five decades has shown that the world community is committed to safeguarding all fissile materials and continuing the use of nuclear energy resources. Decisions of a few nations to discard spent nuclear fuels in geologic formations are contrary to the goals of an enduring nuclear fuel cycle and sustainable development being pursued by the world community. The maintenance of an enduring nuclear fuel cycle is dependent on sensible management of all the resources of the fuel cycle, including spent fuels.

  11. Income inequality and the business cycle

    Directory of Open Access Journals (Sweden)

    Shahee Mostafa

    2015-01-01

    Full Text Available This paper first examines the relationship between ordinary least squares estimators of consumption and investment for 36 selected countries with their respective Gini indices. The analysis shows that income inequality is consistent with a smaller estimator of consumption and a greater estimator of investment. Second, the cycles of GDP, consumption and investment are dated separately to determine how the deepness and duration of cycles of those variables are correlated with the Gini indices of countries. The results show that income inequality leads to a deeper and longer decline of GDP, which causes a greater cumulative income loss of GDP during recession, and a somewhat faster speed of recovery during expansion. Likewise, the result of a correlation between Gini indices and the number of cycles in consumption, investment and GDP indicate that income inequality is associated with a greater number of cycles in consumption and GDP and a lower number of cycles in investment.

  12. Life-cycle assessment of semiconductors

    CERN Document Server

    Boyd, Sarah B

    2012-01-01

    Life-Cycle Assessment of Semiconductors presents the first and thus far only available transparent and complete life cycle assessment of semiconductor devices. A lack of reliable semiconductor LCA data has been a major challenge to evaluation of the potential environmental benefits of information technologies (IT). The analysis and results presented in this book will allow a higher degree of confidence and certainty in decisions concerning the use of IT in efforts to reduce climate change and other environmental effects. Coverage includes but is not limited to semiconductor manufacturing trends by product type and geography, unique coverage of life-cycle assessment, with a focus on uncertainty and sensitivity analysis of energy and global warming missions for CMOS logic devices, life cycle assessment of flash memory and life cycle assessment of DRAM. The information and conclusions discussed here will be highly relevant and useful to individuals and institutions. The book also: Provides a detailed, complete a...

  13. LIFE CYCLE BIOASSAY FOR ASSESSMENT OF THE EFFECTS OF TOXIC CHEMICALS USING RAPID CYCLING OF BRASSICA

    Science.gov (United States)

    Initial evaluation of a new plant life cycle bioassay for the assessment of the effects of toxic chemicals is presented. he bioassay features a rapid cycling Brassica species that can complete its life cycle in as little as 36 days. he herbicide dalapon (2,2 dichloropropionic aci...

  14. Dual Expander Cycle Rocket Engine with an Intermediate, Closed-cycle Heat Exchanger

    Science.gov (United States)

    Greene, William D. (Inventor)

    2008-01-01

    A dual expander cycle (DEC) rocket engine with an intermediate closed-cycle heat exchanger is provided. A conventional DEC rocket engine has a closed-cycle heat exchanger thermally coupled thereto. The heat exchanger utilizes heat extracted from the engine's fuel circuit to drive the engine's oxidizer turbomachinery.

  15. The spatial dimension of cycle logistics

    Directory of Open Access Journals (Sweden)

    Luca Staricco

    2016-08-01

    Full Text Available Cycle logistics is emerging as a promising alternative in urban freight transport. Compared to fossil fuelled vans, the use of cycles for delivering goods within urban areas offers advantages in terms of environmental friendliness, economic efficiency, flexibility, and liveability of urban neighbourhood. At the same time, cycle logistics has to face limits in terms of weight and volume of goods that can be delivered, distances that can be covered, and spatial urban structures that can be served. This latter issue has till now received less attention in the scientific literature: it is generally recognized that cycle logistics performs at its best in inner urban areas, but no systematic study has been realized to identify specific spatial requisites for the effectiveness of cycle logistics. This paper provides a brief review of the main issues that emerge from the literature over cycle logistics, and contributes to stimulate the debate over the spatial dimension of cycle logistics: it presents a classification of cycle logistics schemes, on the basis of their integration with other urban logistic facilities and of the spatial structure of delivery operations. A three-level classification is proposed, depending on the type of goods consolidation: only distribution without consolidation, consolidation in a fixed urban consolidation centre, or consolidation in a mobile depot; for each level, operational examples and case studies are provided. This systematizing typology could support both public and private operators in decisions about the organization of cycle logistics facilities, such as the location of urban consolidation centres or the composition of cycle fleets.

  16. Pipeline bottoming cycle study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    The technical and economic feasibility of applying bottoming cycles to the prime movers that drive the compressors of natural gas pipelines was studied. These bottoming cycles convert some of the waste heat from the exhaust gas of the prime movers into shaft power and conserve gas. Three typical compressor station sites were selected, each on a different pipeline. Although the prime movers were different, they were similar enough in exhaust gas flow rate and temperature that a single bottoming cycle system could be designed, with some modifications, for all three sites. Preliminary design included selection of the bottoming cycle working fluid, optimization of the cycle, and design of the components, such as turbine, vapor generator and condensers. Installation drawings were made and hardware and installation costs were estimated. The results of the economic assessment of retrofitting bottoming cycle systems on the three selected sites indicated that profitability was strongly dependent upon the site-specific installation costs, how the energy was used and the yearly utilization of the apparatus. The study indicated that the bottoming cycles are a competitive investment alternative for certain applications for the pipeline industry. Bottoming cycles are technically feasible. It was concluded that proper design and operating practices would reduce the environmental and safety hazards to acceptable levels. The amount of gas that could be saved through the year 2000 by the adoption of bottoming cycles for two different supply projections was estimated as from 0.296 trillion ft/sup 3/ for a low supply projection to 0.734 trillion ft/sup 3/ for a high supply projection. The potential market for bottoming cycle equipment for the two supply projections varied from 170 to 500 units of varying size. Finally, a demonstration program plan was developed.

  17. Random transitions and cell cycle control.

    Science.gov (United States)

    Brooks, R F

    1981-01-01

    Differences between the cycle times of sister cells are exponentially distributed, which means that these differences can be explained entirely by the existence of a single critical step in the cell cycle which occurs at random. Cycle times as a whole are not exponentially distributed, indicating an additional source of variation in the cell cycle. It follows that this additional variation must affect sister cells identically; ie, sister cell cycle times are correlated. This correlation and the overall distribution of cycle times can be predicted quantitatively by a model that was developed initially in order to explain certain problematic features of the response of quiescent cells to mitogenic stimulation - in particular, the significance of the lag that almost invariably occurs between stimulation and the onset of DNA synthesis. This model proposes that each cell cycle depends not on one but two random transitions, one of which (at reasonably high growth rates) occurs in the mother cell, its effects being inherited equally by the two daughter cells. The fundamental timing element in the cell cycle is proposed to be a lengthy process, called L, which accounts for most of the lag on mitogenic stimulation and also for the minimum cycle time in growing cultures. One of the random transitions is concerned with the initiation of L, whereas the other becomes possible on completion of L. The latter transition has two consequences: the first is the initiation of a sequence of events which includes S, G2 and M; the second is the restoration of the state from which L may be initiated once more. As a result, L may begin (at random) at any stage of the conventional cycle, ie, S, G2, M, or G1. There are marked similarities between the hypothetical process L and the biogenesis of mitotic centres - the structures responsible for organising the spindle poles. PMID:7312875

  18. The timing of the cognitive cycle.

    Directory of Open Access Journals (Sweden)

    Tamas Madl

    Full Text Available We propose that human cognition consists of cascading cycles of recurring brain events. Each cognitive cycle senses the current situation, interprets it with reference to ongoing goals, and then selects an internal or external action in response. While most aspects of the cognitive cycle are unconscious, each cycle also yields a momentary "ignition" of conscious broadcasting. Neuroscientists have independently proposed ideas similar to the cognitive cycle, the fundamental hypothesis of the LIDA model of cognition. High-level cognition, such as deliberation, planning, etc., is typically enabled by multiple cognitive cycles. In this paper we describe a timing model LIDA's cognitive cycle. Based on empirical and simulation data we propose that an initial phase of perception (stimulus recognition occurs 80-100 ms from stimulus onset under optimal conditions. It is followed by a conscious episode (broadcast 200-280 ms after stimulus onset, and an action selection phase 60-110 ms from the start of the conscious phase. One cognitive cycle would therefore take 260-390 ms. The LIDA timing model is consistent with brain evidence indicating a fundamental role for a theta-gamma wave, spreading forward from sensory cortices to rostral corticothalamic regions. This posteriofrontal theta-gamma wave may be experienced as a conscious perceptual event starting at 200-280 ms post stimulus. The action selection component of the cycle is proposed to involve frontal, striatal and cerebellar regions. Thus the cycle is inherently recurrent, as the anatomy of the thalamocortical system suggests. The LIDA model fits a large body of cognitive and neuroscientific evidence. Finally, we describe two LIDA-based software agents: the LIDA Reaction Time agent that simulates human performance in a simple reaction time task, and the LIDA Allport agent which models phenomenal simultaneity within timeframes comparable to human subjects. While there are many models of reaction time

  19. A review on Life Cycle Assessment, Life Cycle Energy Assessment and Life Cycle Carbon Emissions Assessment on buildings

    International Nuclear Information System (INIS)

    Highlights: • Three streams of life cycle studies, namely LCA, LCEA and LCCO2A, were compared. • Previous findings from the three streams were reviewed. • Cases led to discrepancies of results arising from different types of life cycle studies were discussed. • Limitations in using life cycle studies as decision tools for building design were identified. - Abstract: This paper provides a review on three streams of life cycle studies that have been frequently applied to evaluate the environmental impacts of building construction with a major focus on whether they can be used for decision making. The three streams are Life Cycle Assessment (LCA), Life Cycle Energy Assessment (LCEA) and Life Cycle Carbon Emissions Assessment (LCCO2A). They were compared against their evaluation objectives, methodologies, and findings. Although they share similar objectives in evaluating the environmental impacts over the life cycle of building construction, they show some differences in the major focuses of evaluation and methodologies employed. Generally, it has been revealed that quite consistent results can be derived from the three streams with regard to the relative contribution of different phases of life cycle. However, discrepancies occur among the findings obtained from the three streams when different compositions of fuel mixes are used in power generation, or when the overall impacts are not contributed mostly by greenhouse gases emissions. The use of different functional units in different studies also makes it difficult to compare results with benchmarks or results from previous studies. Besides, there are drawbacks in boundary scoping, methodology framework, data inventory and practices which impair their usefulness as a decision making support tool for sustainable building designs

  20. A Model for Wilson Cycles

    Science.gov (United States)

    Coakley, B.

    2001-12-01

    While the steady state tectonics of subduction are reasonably well understood, the initiation of subduction is not. Theoretical and modeling studies of subduction initiation require large, sustained in-plane stresses to break the continuous oceanic plate and drive the slab into the mantle before a new subduction zone can be self-sustaining. These studies have identified sediment loading and old, dense oceanic lithosphere associated with passive margins as factors favoring the localization of subduction. Old oceanic lithosphere is also quite strong, increasing the stress necessary to break the plate, making passive margins less appealing as a locale for initiation. In contrast to breaking the plate in-plane, a subduction zone could grow laterally, by crack propagation, extending to join a passive margin. "Primed" by the bouyancy flux of the pre-existing subduction zone, progressive failure along a passive continental margin would disrupt the oceanic lithosphere and become self-sustaining as the dense plate sank into the mantle, accelerating the tear. The Caribbean plate provides an example of how a micro-plate might nucleate a subduction zone through stress concentration. As the Caribbean plate advanced, the subduction zone at its leading, eastern edge was progressively channeled to the south as first Cuba and then Hispanola were jammed against the Bahamas platform. The Antilles arc is the current site of active subduction. The Caribbean plate is being over-ridden at the Muertos trough, south of Puerto Rico, and at the northern limit of South America and is over-riding the Pacific plate on the west and the North American plate on the east. The Caribbean plate is pinned between the three surrounding plates, which may provide the necessary stress concentration which could lead to the development of a new active margin on the East coast of North America. Wilson cycle tectonics, as seen in the Phanerozoic history of North Atlantic passive margins, require that passive