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  1. 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.

  2. 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"

  3. What is Orobanche haenseleri var. deludens Beck?

    OpenAIRE

    Pujadas Salvà, Antonio J.; Plaza Arregui, Laura

    2004-01-01

    Orobanche haenseleri var. deludens Beck (Orobanchaceae), a problematic taxon described from Algeciras (Cádiz, S Spain) is here identified after studying the original material of Wolley-Dod (BM 4476). It is considered to be the same as O. austrohispanica M.J.Y. Foley and better included, as a variety, under O. gracilis Sm. The new combination O. gracilis var. deludens (Beck) A. Pujadas is consequently proposed. It mainly parasites Ulex (Fabaceae) in the western Mediterranean Region (Iberian Pe...

  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. What is Orobanche haenseleri var. deludens Beck?

    Directory of Open Access Journals (Sweden)

    Pujadas Salvà, Antonio J.

    2004-12-01

    Full Text Available Orobanche haenseleri var. deludens Beck (Orobanchaceae, a problematic taxon described from Algeciras (Cádiz, S Spain is here identified after studying the original material of Wolley-Dod (BM 4476. It is considered to be the same as O. austrohispanica M.J.Y. Foley and better included, as a variety, under O. gracilis Sm. The new combination O. gracilis var. deludens (Beck A. Pujadas is consequently proposed. It mainly parasites Ulex (Fabaceae in the western Mediterranean Region (Iberian Peninsula and NW Africa.Se identifica Orobanche haenseleri var. deludens Beck (Orobanchaceae, un taxon conflictivo descrito de Algeciras (Cádiz, sur de España, a partir del análisis del material original de Wolley-Dod (BM 4476. Se considera que es lo mismo que O. austrohispanica M.J.Y. Foley, y se incluye en O. gracilis Sm. con rango varietal. Se propone la nueva combinación O. gracilis var. deludens (Beck A. Pujadas. Parasita principalmente a especies del género Ulex (Fabaceae en la Región Mediterránea Occidental (Península Ibérica y noroeste de África.

  6. Kashin-Beck disease: a historical overview

    OpenAIRE

    Yamamuro, T.

    2001-01-01

    In 1919, the first report on Kashin-Beck disease (KBD) made by a Japanese doctor described an endemic occurrence in the northern district of Korea. In the 1930s, Dr. Takamori and his colleagues at Manchuria Medical College produced a series of reports on its endemiology, clinical and roentgenological findings observed in the north-eastern district of China. In 1940s, a Tokyo University group led by Dr. Ogata found that the salivary glands of KBD patients were markedly degenerated. Administrat...

  7. Beck Anxiety Inventory: translation and validation of a Norwegian version

    OpenAIRE

    2001-01-01

    This study investigated the psychometric properties of the Norwegian version of the Beck Anxiety Inventory (BAI) in a community sample of 879 respondents and two student samples of a total of 408 respondents. Scores on the BAI were compared to the State-trait Anxiety Inventory, the Beck Depression Inventory-II, three subscales of the SCL-90, the White Bear Suppression Inventory, the Penn State Worry Questionnaire, and the Fear Questionnaire. The BAI demonstrated good psychometric properties w...

  8. 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.

  9. 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...

  10. 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.

  11. 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.

  12. 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

  13. Comparison of the Validities of the Beck, Zung, and MMPI Depression Scales.

    Science.gov (United States)

    Schaefer, Allan; And Others

    1985-01-01

    Surveyed 101 inpatient psychiatric patients and 99 chemical dependency patients to compare the validities of the Beck Depression Inventory, the Minnesota Multiphasic personality Inventory (MMPI) Depression scale, and the Zung Self-Rating Depression Scale. The Zung produced better validity coefficients than the Beck, which yielded higher…

  14. Zung, Beck, and Hamilton Rating Scales as Measures of Treatment Outcome: A Meta-Analytic Comparison.

    Science.gov (United States)

    Lambert, Michael J.; And Others

    1986-01-01

    Treatment studies using the Zung Self-Rating Scale, the Beck Depression Inventory, and the Hamilton Rating Scale for Depression as dependent measures were reviewed to determine whether these scales provide comparable data for assessing treatment effects. Results indicated that the Zung and the Beck showed less change in depression following…

  15. Comparison of Factor Structure Models for the Beck Depression Inventory--II

    Science.gov (United States)

    Ward, L. Charles

    2006-01-01

    Factor analyses of the Beck Depression Inventory--II (A. T. Beck, R. A. Steer, & G. K. Brown, 1996) have frequently produced 2 different 2-factor oblique structures. The author used confirmatory factor analyses to compare these structures with a general-factor model with 2 orthogonal group factors. The general-factor model fit as well as or better…

  16. 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...

  17. 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.

  18. [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)

  19. 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…

  20. [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

  1. 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....

  2. 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)

  3. 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…

  4. Orobanche tunetanaG. Beck (Orobanchaceae), a new species for the European continent

    OpenAIRE

    Pujadas-Salvá, Antonio J.; Lora González, Ángel; Crespo Villalba, Manuel B.

    1997-01-01

    The presence of Orobanche tunetana G. Beck in the south-eastern part of the Iberian Peninsula is noted. An original illustration, the chorology and the description of the Iberian specimens are given. The differences are also analysed between this species and O. caesia Rchb.. with which it shows certain similarities.

  5. 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…

  6. 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…

  7. 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…

  8. The Latent Symptom Structure of the Beck Depression Inventory-II in Outpatients with Major Depression

    Science.gov (United States)

    Quilty, Lena C.; Zhang, K. Anne; Bagby, R. Michael

    2010-01-01

    The Beck Depression Inventory-II (BDI-II) is a self-report instrument frequently used in clinical and research settings to assess depression severity. Although investigators have examined the factor structure of the BDI-II, a clear consensus on the best fitting model has not yet emerged, resulting in different recommendations regarding how to best…

  9. 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.

  10. Orobanche tunetana G. Beck (Orobanchaceae, especie nueva para el continente europeo

    Directory of Open Access Journals (Sweden)

    Pujadas, Antonio

    1997-12-01

    Full Text Available The presence of Orobanche tunetana G. Beck in the south-eastern part of the Iberian Península is noted. An original ilhistrabon, the chorology and the description of the Iberian specimens are given. The differences are also analysed between this species and O. caesia Rchb.. with which it shows certain similarities.Se indica la presencia de Orobanche tunetana G. Beck en el sudeste de la Península Ibérica. Aportamos un icono original, la corología y la descripción de los ejemplares ibéricos. Se analizan las diferencias con O. caesia Rchb., con el que presenta ciertas semejanzas.

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

    OpenAIRE

    DİNÇ, Mehmet

    2012-01-01

    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 sevent...

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

    OpenAIRE

    Atilla Senih Mayda 1; Muammer Yılmaz 1; Filiz Bolu; et al.

    2015-01-01

    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: A...

  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. Aaron T. Beck's drawings and the psychoanalytic origin story of cognitive therapy.

    Science.gov (United States)

    Rosner, Rachael I

    2012-02-01

    In this essay the author challenges the standard origin story of cognitive therapy, namely, that its founder Aaron T. Beck broke with psychoanalysis to pursue a more pragmatic, parsimonious, and experimentalist cognitive model. It is true that Beck broke with psychoanalysis in large measure as a result of his experimental disconfirmation of key psychoanalytic ideas. His new school of cognitive therapy brought the experimental ethos into every corner of psychological life, extending outward into the largest multisite randomized controlled studies of psychotherapy ever attempted and inward into the deepest recesses of our private worlds. But newly discovered hand-sketched drawings from 1964 of the schema, a conceptual centerpiece of cognitive therapy, as well as unpublished personal correspondence show that Beck continued to think psychoanalytically even after he broke with psychoanalysis. The drawings urge us to consider an origin story much more complex than the one of inherited tradition. This new, multifaceted origin story of cognitive therapy reaches beyond sectarian disagreements and speaks to a broader understanding of the theoretical underpinnings of cognitive therapy. PMID:22530375

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

    DEFF Research Database (Denmark)

    Zhang, Ya-xu; Dong, Wei; Liu, Hui; Cicuttini, Flavia; de Courten, Maximilian; Yang, Jian-bai

    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...... overall mean change in joint space was significant between the two groups (P <0.0001). Knee joint space of the experimental group narrowed slowly compared to the control group. Therefore, chondroitin sulfate and glucosamine might play a protective role in preserving articular cartilage and provide...

  16. 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.

  17. 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

  18. 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

  19. Orobanche tunetana G. Beck (Orobanchaceae), especie nueva para el continente europeo

    OpenAIRE

    Pujadas, Antonio; Lora, Ángel; Crespo, Manuel B.

    1997-01-01

    The presence of Orobanche tunetana G. Beck in the south-eastern part of the Iberian Península is noted. An original ilhistrabon, the chorology and the description of the Iberian specimens are given. The differences are also analysed between this species and O. caesia Rchb.. with which it shows certain similarities.Se indica la presencia de Orobanche tunetana G. Beck en el sudeste de la Península Ibérica. Aportamos un icono original, la corología y la descripción de los ejemplares ibéricos. Se...

  20. Alpha-Synuclein mRNA Levels Correspond to Beck Depression Inventory Scores in Females with Eating Disorders

    OpenAIRE

    Frieling, Helge; Gozner, Andreas; Römer, Konstanze D.; Wilhelm, Julia; Hillemacher, Thomas; Kornhuber, Johannes; de Zwaan, Martina; Jacoby, Georg E.; Bleich, Stefan

    2013-01-01

    α-Synuclein (α-Syn) is a neuronal protein involved in the regulation of brain serotonin and dopamine levels. We analyzed the peripheral expression of α-Syn mRNA and Beck Depression Inventory scores in female patients suffering from anorexia nervosa (n = 18) or bulimia nervosa (n = 24). We found a significant positive association between α-Syn mRNA expression and the total scores of the Beck Depression Inventory (linear regression; R 2 = 0.20; p = 0.003). α-Syn may play a pathophysiological ro...

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

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    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.

  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. 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.

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

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    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.

  5. 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…

  6. 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…

  7. Validation of the Beck Depression Inventory for a Portuguese-speaking Chinese community in Brazil

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    Y.-P. Wang

    2005-03-01

    Full Text Available The objective of the present study was to investigate the psychometric properties and cross-cultural validity of the Beck Depression Inventory (BDI among ethnic Chinese living in the city of São Paulo, Brazil. The study was conducted on 208 community individuals. Reliability and discriminant analysis were used to test the psychometric properties and validity of the BDI. Principal component analysis was performed to assess the BDI's factor structure for the total sample and by gender. The mean BDI score was lower (6.74, SD = 5.98 than observed in Western counterparts and showed no gender difference, good internal consistency (Cronbach's alpha 0.82, and high discrimination of depressive symptoms (75-100%. Factor analysis extracted two factors for the total sample and each gender: cognitive-affective dimension and somatic dimension. We conclude that depressive symptoms can be reliably assessed by the BDI in the Brazilian Chinese population, with a validity comparable to that for international studies. Indeed, cultural and measurement biases might have influenced the response of Chinese subjects.

  8. 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.

  9. 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

  10. 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

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

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    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.

  12. 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.

  13. 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.

  14. 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...

  15. 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 ...

  16. 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...

  17. 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...

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

    OpenAIRE

    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 level, the functional equivalence (i.e., similarity of meaning) of depression scores at individual and country level was examined. Studies using the BDI in normal populations from 28 countries wer...

  19. Diagnosing Depression in Chronic Pain Patients: DSM-IV Major Depressive Disorder vs. Beck Depression Inventory (BDI)

    OpenAIRE

    Knaster, Peter; Estlander, Ann-Mari; Karlsson, Hasse; Kaprio, Jaakko; Kalso, Eija

    2016-01-01

    Background Diagnosing depression in chronic pain is challenging due to overlapping somatic symptoms. In questionnaires, such as the Beck Depression Inventory (BDI), responses may be influenced more by pain than by the severity of depression. In addition, previous studies have suggested that symptoms of negative self-image, a key element in depression, are uncommon in chronic pain-related depression. The object of this study is to assess the relationship of the somatic and cognitive-emotional ...

  20. An Empirical Investigation of Depression Symptoms: Norms, Psychometric Characteristics and Factor Structure of the Beck Depression Inventory-II

    OpenAIRE

    Aasen, Harald

    2001-01-01

    The present study provides normative data and investigated the psychometric characteristics and factor structure of a Norwegian version of the Beck Depression Inventory-II (BDI-II) in a general population sample (N=875) and a student sample (N=303). High internal consistency of the BDI-II was found in both samples, and sufficient test-retest reliability over a three week period was obtained in the student sample. Results from the student sample further established evidence for convergent and ...

  1. Correlation of Pain Scores, Analgesic Use, and Beck Anxiety Inventory Scores During Hospitalization in Lower Extremity Amputees

    OpenAIRE

    Trame, Cathy D; Greene, Erin; Moddeman, Gail; Booth, Branyan A; Konstantakos, Emmanuel K; Parada, Stephen; Siebuhr, Karl; Laughlin, Richard T.

    2008-01-01

    Post amputation pain can be debilitating for patients and families. Chronic pain is a common phenomenon after lower extremity amputation, occurring in up to 80% of this population. The purpose of this pilot study was to correlate post amputation pain scores to opioid analgesic consumption and Beck Anxiety Inventory (BAI) scores. Twenty-three patients with lower extremity amputation at an 827-bed acute care inner-city hospital were surveyed pre-operatively and post-operatively to determine if ...

  2. Low selenium environment and Vitamin E in human serum relative to the Kaschin-Beck's disease

    Energy Technology Data Exchange (ETDEWEB)

    Hou, S.; Zhu, Z.

    1982-04-30

    In China, endemic regions of Kaschin-Beck's disease, Keshan disease, and animal white muscle disease basically overlap, mainly the transitional area between the moist Southeast and the arid Northwest. Tests conducted by the authors reveal that the selenium content of major soils of the regions affected by the diseases is 0.088 to 0.360 ppM, that of the grains below 20 to 30 ppB. Of the inhabitants, 94 percent have serum selenium content below 0.031 ..mu..g/l and the selenium content of the hair of inhabitants is 100 to 200 ppB. From July 1979 to June 1980, the authors treated 41 cases of Kaschin-Beck's disease with sodium selenite-V/sub E/ and 36 of them recovered from the disease. Based upon these data, the authors believe that environmental selenium deficiency of these regions is perhaps the cause of the low level selenium nutrition of the inhabitants. The low level selenium nutrition in turn leads to a reduction of certain enzymic activity to cause the Kaschin-Beck's disease, as well as the Keshan disease and the animal white muscle disease.

  3. 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.

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

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    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.

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

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    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.

  6. 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

  7. 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.

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

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    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.

  9. 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,…

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

    OpenAIRE

    Yujie Ning; Xi Wang; Sen Wang; Feng Zhang; Lianhe Zhang; Yanxia Lei; Xiong Guo

    2015-01-01

    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 determin...

  11. 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.

  12. Local Constructions of Vulnerability and Resilience in the Context of Climate Change. A Comparison of Lübeck and Rostock

    Directory of Open Access Journals (Sweden)

    Gabriela B. Christmann

    2014-02-01

    Full Text Available Climate change is globally defined as a “reality”. This does not mean however that the way in which it is understood is the same all over the world. Rather, perceptions may differ at different places and times, even if physical and geographical conditions are similar. For the time being, this phenomenon has not been dealt with on a theoretical-conceptual level. The article will address this desiderate. Based on the approaches of social constructivism as well as actor-network theory, a theoretical concept will be suggested as a heuristic model for empirical analysis. By the examples of Lübeck and Rostock, two cities on Germany’s Baltic coast, it will be shown that climate change related perceptions of vulnerability and resilience may build on physical-material aspects but that they are above all considerably interwoven with specific cultural and social patterns of interpretation. In the framework of the local discourse in Lübeck, it is the strong Hanseatic tradition which consumes the climate change issue, whereas in Rostock it is the problems and historical breaks of a transformation society which shape the way of viewing climate change.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. [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

  15. 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

  16. Hyaluronic acid and glucosamine sulfate for adult Kashin-Beck disease: a cluster-randomized, placebo-controlled study.

    Science.gov (United States)

    Xia, Chuan-Tao; Yu, Fang-Fang; Ren, Feng-Ling; Fang, Hua; Guo, Xiong

    2016-05-01

    To evaluate the efficacy and safety of hyaluronic acid (HA) and glucosamine sulfate (GS) in alleviating symptoms and improving function of Kashin-Beck disease (KBD). A cluster-randomized, placebo-controlled trial was conducted in 150 patients with KBD. Participants were randomly allocated to receive intra-articular injection hyaluronic acid (IAHA) for 4 weeks, oral GS for 12 weeks, or oral placebo for 12 weeks. The primary outcome measures were 20 % and 50 % reductions in pain from baseline measured by the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index. Secondary outcome measures included WOMAC index parameters of pain, stiffness, and physical function. The third outcome measure was mean change in Lequence score. HA and GS were effective in reducing WOMAC pain by 20 % (differences of 43.5 % and 25.4 %) and 50 % (differences of 43.4 % and 26.9 %). Both HA and GS significantly reduced WOMAC pain, WOMAC stiffness, and WOMAC normalized score compared with placebo group (all P < 0.05). IAHA was significantly more effective than oral GS in improving WOMAC normalized score (P = 0.034), pain (P = 0.002), stiffness (P = 0.018), and function (P = 0.044). The results indicate that HA and GS were more effective than placebo in treating KBD and HA was more effective than GS. PMID:25388643

  17. 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.

  18. Predicted ferromagnetic insulator CrO2/TiO2 superlattice with the modified Becke-Johnson potential

    Science.gov (United States)

    Guo, San-Dong

    2015-11-01

    The ferromagnetic insulator plays a major role in high-performance spintronic applications. So, it is very necessary to search for better ferromagnetic insulators that are compatible with current semiconductor technology. We investigate the electronic structures and magnetic properties of the \\text{Cr}{{\\text{O}}2}/\\text{Ti}{{\\text{O}}2} superlattice by using Tran and Blaha’s modified Becke and Johnson exchange potential. The calculated results show that the \\text{Cr}{{\\text{O}}2}/\\text{Ti}{{\\text{O}}2} superlattice is a ferromagnetic insulator, which combines ferromagnetic properties of \\text{Cr}{{\\text{O}}2} with insulating properties of \\text{Ti}{{\\text{O}}2} . The ferromagnetic stability is proven by magnetic energy differences for a series of lattice constants a. It is very interesting that both the majority-spin channel and spin non-conservation gaps firstly decrease with increasing lattice constants a, and then increase. However, the minority-spin channel gap firstly decreases, then remains nearly steady. These trends of gaps can be understood by changes of electronic band structures. If the \\text{Cr}{{\\text{O}}2}/\\text{Ti}{{\\text{O}}2} superlattice was experimentally synthesized with ferromagnetic insulator properties, it should be used to design high-performance spintronic devices, achieving new functionality.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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...

  8. 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- ...

  9. 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...

  10. Study of the internal and concurrent validity of the Beck Depression Inventory for primary care settings in pregnant population of metropolitan Lima, May-June 2008

    OpenAIRE

    Enrique Gil; Eduardo Espinoza; Elizabeth Mori; Hans Contreras; Nelly Lam; Giulianna Córdova

    2009-01-01

    Objective: To evaluate the internal and concurrent validity of the Beck Depression Inventory for Primary Care (BDI-PC) in pregnant women from Lima, Peru. Methods: We perform an analytic observational cross-sectional study at the Instituto Nacional Materno Perinatal (INMP). The study included 307 pregnant women attending the Fetal Medicine Service at the INMP, from May to June 2008. To assess theconcurrent validity we used the Edinburgh Depression Scale (EPDS), and calculated Cronbach’s Alpha,...

  11. Contents, Species of Soil Selenium in Kashin-beck Disease-endemic Area, Ruoergai Wetland, Sichuan, China

    Directory of Open Access Journals (Sweden)

    Ying-bing Tian

    2013-04-01

    Full Text Available This study studied that the amounts, species of Se in four kinds of soil (sandy soil, meadow soil, bog soil and peat soil by a method of successive extraction in order to accumulate scientific data for preventing and curing the selenium response symptom of people and livestock in Ruoergai wetland. The results showed that the content range of Total Se (T-Se in surface soil layer was 65-260 μg/kg in ten sampling sites and the low Se circumstance existed because of soil Se deficiency. Among several kinds of Se forms, Water soluble Se (W-Se, Exchangeable Se (E-Se and Organic Se (O-Se accounted for 1.12-3.08%, 2.91-6.03% and 10.28-45.6% of total Se respectively, unavailable Se including Acid soluble Se (A-Se, Sulfidic Se (S-Se and Residual Se (R-Se accounted for more than 60% of total Se. Of the soil O-Se, 57.84% (on average was associated with the Humic Acid fraction (HA-Se and 42.16% with the Fulvic Acid fraction (FA-Se, the range of C/Se in soil organic matter was 0.65×106-7.28×106 (on average 2.96×106 in surface soil layer. The soil organic matter was the most important factor affecting the content of soil T-Se and O-Se, the rich soil organic matter was helpful to the accumulation of soil T-Se and O-Se. It was clear that the lower utilization ratio of Se due to the low content of soil T-Se, the higher portion of O-Se and HA-Se were the possible reason for a deficiency of selenium in Kashin-Beck Disease-endemic area, Ruoergai wetland, Sichuan, China.

  12. 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

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

    Science.gov (United States)

    Ning, Yujie; Wang, Xi; Wang, Sen; Zhang, Feng; Zhang, Lianhe; Lei, Yanxia; Guo, Xiong

    2015-08-01

    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 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. PMID:26225999

  14. 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.

  15. 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.

  16. [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).

  17. Prevalence of Selenium, T-2 Toxin, and Deoxynivalenol in Kashin-Beck Disease Areas in Qinghai Province, Northwest China.

    Science.gov (United States)

    Lei, Ronghui; Jiang, Ning; Zhang, Qiang; Hu, Senke; Dennis, Bannel Sando; He, Shanshan; Guo, Xiong

    2016-05-01

    The aim of this study was to determine the levels of selenium, T-2 toxin, and deoxynivalenol (DON) contamination in Kashin-Beck disease (KBD) areas and provide information for understanding the high prevalence of KBD in Qinghai Province. A total of 183 subjects were chosen in a KBD-prevalent county (Guide County) and a non-KBD county (Huangzhong County) in Qinghai Province, northwestern China, and the samples of wheat flour, soil, drinking water and blood, urine, and hair of children were collected from these residents. The selenium concentrations from all these sources were determined using atomic fluorescence spectrophotometry. The levels of T-2 toxin and DON contamination in the wheat flour samples were assayed using HPLC-MS/MS. The average selenium content in the soil, drinking water, and wheat flour samples from KBD areas were 26.93 ± 10.06 μg/kg, 0.097 ± 0.038 μg/L, and 9.50 ± 7.17 μg/kg, respectively. Among these, the selenium levels in the drinking water and wheat flour samples from the KBD endemic county were significantly lower than those from the non-KBD county. For the selenium nutrient status, only the hair selenium concentration of children from the KBD endemic county was significantly lower than that from the non-KBD county. The contents of T-2 toxin in all wheat samples were below the detection limit (0.4 μg/kg). The levels of DON contamination in wheat flour samples from KBD and non-KBD children's households within the KBD endemic county were relatively higher, with average levels of 302 ± 49 and 280 ± 48 μg/kg, respectively. The DON level of wheat flour samples from the children's households in the non-KBD county was significantly lower than that from the KBD endemic county. These results suggest that the lower selenium status in Guide County still remains. While the selenium nutritional status of the local children has improved to some extent, partly due to the introduction of food produce from nonlocal areas

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

    OpenAIRE

    Jesús Sanz; María Paz García-Vera

    2013-01-01

    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...

  19. Aplicación práctica de los modelos de Mercer y Beck en las especialidades de enfermería

    OpenAIRE

    Berlanga Fernández, Sofía; Pérez Cañaveras, Rosa María; Vizcaya Moreno, María Flores

    2012-01-01

    El vínculo afectivo es la atracción que un individuo siente por otro. La conducta de apego busca la unión emocional y seguridad del bebé hacia su madre. Distintas especialidades de enfermería indican la importancia de trabajar el vínculo afectivo, las relaciones familiares y utilizar el proceso enfermero partiendo de modelos conceptuales. Los modelos conceptuales de Mercer y Beck estudian factores a considerar en la formación y desarrollo de vínculos afectivos entre madres e hijos. Este estud...

  20. 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

    OpenAIRE

    Andrade L.; Gorenstein C.; Vieira Filho A.H.; Tung T.C.; Artes R.

    2001-01-01

    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 s...

  1. 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.

  2. Sulfur cycle

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.

    Microbes, especially bacteria, play an important role in oxidative and reductive cycle of sulfur. The oxidative part of the cycle is mediated by photosynthetic bacteria in the presence of light energy and chemosynthetic forms in the absence of light...

  3. 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...

  4. Cycling injuries.

    OpenAIRE

    Cohen, G. C.

    1993-01-01

    Bicycle-related injuries have increased as cycling has become more popular. Most injuries to recreational riders are associated with overuse or improper fit of the bicycle. Injuries to racers often result from high speeds, which predispose riders to muscle strains, collisions, and falls. Cyclists contact bicycles at the pedals, seat, and handlebars. Each is associated with particular cycling injuries.

  5. 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

  6. Salt-Rich Selenium for Prevention and Control Children with Kashin-Beck Disease: a Meta-analysis of Community-Based Trial.

    Science.gov (United States)

    Yu, Fang-fang; Han, Jing; Wang, Xi; Fang, Hua; Liu, Huan; Guo, Xiong

    2016-03-01

    Kashin-Beck disease (KBD) in western China is not well controlled. The objective of this study is to evaluate prevention and control children with KBD through a meta-analysis of a community-based trial. Web of knowledge, PubMed, Elsevier, the Chinese National Knowledge Infrastructure (CNKI), VIP and Wanfang data had been electronically searched up to February 2015. Search terms included the trial terms "Salt rich selenium" and "Kashin-Beck disease." Eligible studies were prospective trials of salt-rich selenium in endemic villages. Data extraction was performed by two authors using predefined data fields that also included quality evaluation. Of 292 potentially relevant articles initially screened, reporting 11 community-based trials with a total enrollment of 2652 participants were included, from five provinces in China. The pooled odds ratios (OR) and 95 % confidence intervals (CI) of primary prevention in healthy children were 0.16 and 0.08∼0.33, respectively. The OR and 95 % CI of clinical improvement in KBD children were 6.57 and 3.33∼12.93, respectively. The OR of repairing rate of metaphysis lesions was 5.53 (95 % CI 2.92∼10.47) based on X-ray film, which was statistically significantly different in favor of salt-rich selenium. The combined standard mean difference (SMD) of selenium content in hair was 2.54 (95 % CI 1.21∼3.87) which was significantly higher in selenium group. Current evidence showed that supplement salt-rich selenium was effective in reducing new incidence in healthy children and clinical improvement including repairing metaphysis lesions instead of repairing distal end of phalanx lesions in KBD children. PMID:26198135

  7. Glacial cycles

    DEFF Research Database (Denmark)

    Kaufmann, R. K.; Juselius, Katarina

    We use a statistical model, the cointegrated vector autoregressive model, to assess the degree to which variations in Earth's orbit and endogenous climate dynamics can be used to simulate glacial cycles during the late Quaternary (390 kyr-present). To do so, we estimate models of varying complexity...... 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...... to simulate glacial cycles accurately. Also, results suggest that non-linear 10 dynamics, threshold effects, and/or free oscillations may not play an overriding role in glacial cycles....

  8. 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

  9. 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.

  10. '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.

  11. 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.

  12. 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...

  13. 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.

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

    Science.gov (United States)

    Zhang, Yubo; Wang, Youwei; Xi, Lili; Qiu, Ruihao; Shi, Xun; Zhang, Peihong; Zhang, Wenqing

    2014-02-21

    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. PMID:24559355

  15. 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.

  16. 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

  17. Elements regulation during cartilage and bone deformity - potential clinical index in early diagnosis, monitoring and prognosis in children of kashin - beck disease

    International Nuclear Information System (INIS)

    Background: Kashin-Beck Disease (KBD) is a chronic deforming osteoarthritis starting in early childhood and affecting the cartilage metabolism and endochondral ossification. Selenium (Se) deficiency has been postulated as the major environmental etiological factor for KBD by many studies. Other minerals such as the Manganese (Mn) and calcium (Ca) which don't have uniform distribution in environment are also important elements involved in bone and cartilage formation but their regulation in KBD has been rarely reported. The study was done to investigate the role of Mn and Ca in addition to Se in KBD. Method: In this study, the Se, Mn and Calevels were investigated in children from different groups (KBD group, Healthy group from KBD endemic areas (inner control group), Healthy group (outer control group) from Non KBD areas and KBD group with selenium supplementation). The contents of Mn, S and Ca in serum and hair were analyzed by inductively coupled plasma mass spectrometry. Results: The increased Mn levels of. serum and hair in KBD children were observed compared with normal groups. The Mn and Ca have similar trends in different groups but Se and Mn displayed reversed trends. Conclusions: The Mn and Ca contributed to KBD pathogenesis combined with se in regulation of growth and development. The relative ratio of Mn to Se can be a potential clinical index in early diagnosis, monitoring and prognosis of KBD in children. (author)

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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

  6. 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

  7. Fuel cycle

    International Nuclear Information System (INIS)

    The situation of the nuclear fuel cycle for LWR type reactors in France and in the Federal Republic of Germany was presented in 14 lectures with the aim to compare the state-of-the-art in both countries. In addition to the momentarily changing fuilds of fuel element development and fueling strategies, the situation of reprocessing, made interesting by some recent developmnts, was portrayed and differences in ultimate waste disposal elucidated. (orig.)

  8. [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

  9. Safe cycling!

    CERN Multimedia

    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...

  10. 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.

  11. Electronic and optical properties of ZnSc2S4 and CdSc2S4 cubic spinels by the modified Becke-Johnson density functional

    Science.gov (United States)

    Bouhemadou, A.; Al-Essa, S.; Allali, D.; Ghebouli, M. A.; Bin-Omran, S.

    2013-06-01

    Structural, electronic and optical properties of the ZnSc2S4 and CdSc2S4 cubic spinels have been investigated by means of the full-potential (linearized) augmented plane wave plus local orbitals based on density functional theory. The exchange-correlation potential is treated by the GGA-PBEsol [J.P. Perdew, A. Ruzsinszky, G.I. Csonka, O.A. Vydrov, G.E. Scuseria, L.A. Constantin, X. Zhou, K. Burke, Phys. Rev. Lett. 100 (2008) 136406] and the recently proposed modified Becke-Johnson potential approximation (mBJ) [F. Tran, P. Blaha, Phys. Rev. Lett. 102 (2009) 226401], which successfully corrects the band-gap problem found with GGA for a wide range of materials. The obtained structural parameters are in good agreement with the available experimental data. This gives support for the predict properties for ZnSc2S4 and CdSc2S4. The band structures reveal that both compounds are semiconductor with a direct gap. The obtained gap values show that mBJ is superior for estimating band gap energy. We have calculated the electron and hole effective masses in different directions. The density of states has been analyzed. Based on our electronic structure obtained using the mBJ method we have calculated various optical properties, including the complex dielectric function ɛ(ω), complex index of refraction n(ω), reflectivity coefficient R(ω), absorption coefficient α(ω) and electron energy-loss function L(ω) as functions of the photon energy. We find that the values of zero-frequency limit ɛ1(0) increase with decreasing the energy band gap in agreement with the Penn model. The origin of the peaks and structures in the optical spectra is determined in terms of the calculated energy band structures.

  12. The accuracy of diagnosis of major depression in patients with Parkinson's disease: a comparative study among the UPDRS, the geriatric depression scale and the Beck depression inventory A precisão do diagnóstico de depressão na doença de Parkinson: um estudo comparativo entre a UPDRS, a escala geriátrica de depressão e o inventário de depressão de Beck

    OpenAIRE

    Vitor Tumas; Guilherme Gustavo Ricioppo Rodrigues; Tarsis Leonardo Almeida Farias; Crippa, José Alexandre S.

    2008-01-01

    OBJECTIVE: Evaluate the accuracy of diagnosis of major depression in patients with Parkinson's disease (PD) using the UPDRS, the 15-item Geriatric Depression Scale (GDS15) and the Beck Depression Inventory (BDI). METHOD: 50 consecutive patients with PD were evaluated. The diagnosis of major depression was made according to the DSM-IV criteria. RESULTS: We found a 24% prevalence of major depression. All depression scales were highly correlated but UPDRS depression item had the lowest diagnosti...

  13. En kommentar til Becks model

    DEFF Research Database (Denmark)

    Philipps, Morten; Andersen, Thomas Dyreborg

    2014-01-01

    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......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...

  14. 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

  15. 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

  16. 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.

  17. Relación empírica entre la Terapia Racional Emotivo-Conductual (TREC) de Ellis y la Terapia Cognitiva (TC) de Beck en una muestra costarricense

    OpenAIRE

    Hannia Cabezas Pizarro; Leonor I. Lega

    2006-01-01

    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 c...

  18. 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.

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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....

  5. 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) ...

  6. 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…

  7. 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.

  8. Euro area business cycles

    OpenAIRE

    Atilim Seymen

    2012-01-01

    The role of global, euro area and country-specific shocks in business cycle dynamics of six euro area member countries is assessed with the aid of SVAR models. Output fluctuations are driven by global shocks to a large extent in the euro area, and no Europeanisation of business cycles due to, for example the European Monetary Union, could be established. Business cycle heterogeneity is driven mainly by (asymmetric) country-specific shocks in the euro area and not by heterogeneous responses to...

  9. 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

  10. 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...

  11. 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.

  12. 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)

  13. 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...

  14. [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

  15. 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...

  16. 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)

  17. 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....

  18. Seeing the Carbon Cycle

    Science.gov (United States)

    Drouin, Pamela; Welty, David J.; Repeta, Daniel; Engle-Belknap, Cheryl A.; Cramer, Catherine; Frashure, Kim; Chen, Robert

    2006-01-01

    In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

  19. The carbon cycle revisited

    Science.gov (United States)

    Bolin, Bert; Fung, Inez

    1992-01-01

    Discussions during the Global Change Institute indicated a need to present, in some detail and as accurately as possible, our present knowledge about the carbon cycle, the uncertainties in this knowledge, and the reasons for these uncertainties. We discuss basic issues of internal consistency within the carbon cycle, and end by summarizing the key unknowns.

  20. 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 of the...

  1. Family Life Cycle: 1980.

    Science.gov (United States)

    Norton, Arthur J.

    1983-01-01

    Used data from a 1980 national sample survey to show differences in the timing of major family life-cycle events according to age, social and economic characteristics, and marital history. Results suggest that age generational differences, more than any other factor, influence timing of life-cycle events. (Author/JAC)

  2. 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.

  3. Rock Cycle Roulette.

    Science.gov (United States)

    Schmidt, Stan M.; Palmer, Courtney

    2000-01-01

    Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for…

  4. 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.

  5. Nuclear fuel cycles

    International Nuclear Information System (INIS)

    The source of energy in the nuclear reactors in fission if a heavy nuclei by absorbing a neutron and giving fission products, few neutrons and gamma radiation. The Nuclear Fuel Cycle may be broadly defined as the set of process and operations needed to manufacture nuclear fuels, to irradiate them in nuclear reactors and to treat and store them, temporarily or permanently, after irradiation. Several nuclear fuel cycles may be considered, depending on the type of reactor and the type of fuel used and whether or not the irradiated fuel will be reprocessed. The nuclear fuel cycle starts with uranium exploration and ends with final disposal of the material used and generated during the cycle. For practical reasons the process has been further subdivided into the front-end and the back-end. The front-end of the cycle occurs before irradiation and the back-end begins with the discharge of spent fuel from the reactor

  6. Interlinked Cycles for Index Coding: Generalizing Cycles and Cliques

    OpenAIRE

    Thapa, Chandra; Ong, Lawrence; Johnson, Sarah J.

    2016-01-01

    We consider a graphical approach to index coding. While cycles have been shown to provide coding gain, only disjoint cycles and cliques (a specific type of overlapping cycles) have been exploited in existing literature. In this paper, we define a more general form of overlapping cycles, called the interlinked-cycle (IC) structure, that generalizes cycles and cliques. We propose a scheme, called the interlinked-cycle-cover (ICC) scheme, that leverages IC structures in digraphs to construct sca...

  7. 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.

  8. 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....

  9. 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)

  10. 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.

  11. 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.

  12. The effect of cycling intensity on cycling economy during seated and standing cycling

    OpenAIRE

    Arkesteijn, Marco; Simon A. Jobson; James G Hopker; Passfield, Louis

    2016-01-01

    BACKGROUND: Previous research has shown that cycling in a standing position reduces cycling economy compared with seated cycling. It is unknown whether the cycling intensity moderates the reduction in cycling economy while standing. PURPOSE: The aim was to determine whether the negative effect of standing on cycling economy would be decreased at a higher intensity. METHODS: Ten cyclists cycled in 8 different conditions. Each condition was either at an intensity of 50% or 70% ...

  13. 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.

  14. 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

  15. 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

  16. Bir Öğrenci Yurdunda Kalan Üniversite Öğrencilerindeki İnternet Bağımlılığı İle Beck Depresyon Ölçeği Arasındaki İlişki

    OpenAIRE

    AS, Mayda

    2015-01-01

    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 t...

  17. The Pneumocystis life cycle

    OpenAIRE

    Cécile-Marie Aliouat-Denis; Anna Martinez; El Moukhtar Aliouat; Muriel Pottier; Nausicaa Gantois; Eduardo Dei-Cas

    2009-01-01

    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 seve...

  18. Reviewing the Leverage Cycle

    OpenAIRE

    Ana Fostel; John Geanakoplos

    2013-01-01

    We review the theory of leverage developed in collateral equilibrium models with incomplete markets. We explain how leverage tends to boost asset prices, and create bubbles. We show how leverage can be endogenously determined in equilibrium, and how it depends on volatility. We describe the dynamic feedback properties of leverage, volatility, and asset prices, in what we call the Leverage Cycle. We also describe some cross-sectional implications of multiple leverage cycles, including contagio...

  19. Offshore Rankine Cycles

    OpenAIRE

    Brandsar, Jo

    2012-01-01

    The title of the thesis - "Offshore Rankine Cycles" - is very general and cover a large range of engineering fields, e.g. thermodynamic cycles (Rankine, ORC, Brayton, Kalina, etc.), mechanical equipment (gas/steam turbine, heat exchangers and additional equipment) and safety concerns (flammable and/or toxic fluids, high temperature and pressures), to name the most important.The thesis try to give a brief overview of all critical points and alternatives, concerning employment of a wa...

  20. 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...

  1. 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...

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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 or to...... 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. The...... support decision making toward sustainable production and consumption. In both cases, LCSA results could be too disaggregated and consequently too difficult to understand and interpret by decision makers. As non-experts are usually the target audience of experts and scientists, and are also involved in...

  7. Buoyancy organic Rankine cycle

    Energy Technology Data Exchange (ETDEWEB)

    Schoenmaker, J.; Rey, J.F.Q. [Centro de Engenharia, Modelagem e Ciencias Sociais Aplicadas, Universidade Federal do ABC (CECS-UFABC), Rua Santa Adelia 166, Bairro Bangu, 09210-170 Santo Andre, SP (Brazil); Pirota, K.R. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas (UNICAMP), C.P. 6165, Campinas, SP (Brazil)

    2011-03-15

    In the scope of renewable energy, we draw attention to a little known technique to harness solar and geothermal energy. The design here proposed and analyzed is a conceptual hybrid of several patents. By means of a modified organic Rankine cycle, energy is obtained utilizing buoyancy force of a working fluid. Based on thermodynamic properties we propose and compare the performance of Pentane and Dichloromethane as working fluids. Theoretical efficiencies up to 0.26 are estimated for a 51 m (Pentane) and 71.5 m (Dichloromethane) high column of water in a regime below 100 C operation temperature. These findings are especially relevant in the scope of distributed energy systems, combined cycle plants, and low-temperature Rankine cycles. (author)

  8. 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.

  9. Superfluid thermodynamic cycle refrigerator

    International Nuclear Information System (INIS)

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of 3He in a single phase 3He-4He solution. The 3He in superfluid 4He 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 3He at an initial concentration in superfluid 4He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of 4He while restricting passage of 3He. The 3He 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. 12 figs

  10. 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.

  11. Global Carbon Cycle

    OpenAIRE

    Probst, Jean-Luc; Faure, Hugues; Veizer, Jan

    1999-01-01

    The European Union of Geosciences held its 9th biannual meeting in Strasbourg, March 23–27, 1997. During this meeting, Symposium N8 18, Global carbon Cycle, was held under the sponsorship of the IGCP 1 n8404 on the «Terrestrial Carbon in the past 125 Ka», the INQUA 2 Carbon Commission and the ESCOBA-Biosphere 3 project of the EC Environment and Climate Programme. The «Global Carbon Cycle» Symposium attracted 28 oral and poster presentations and about one hundred par...

  12. Resurrecting Equilibria Through Cycles

    DEFF Research Database (Denmark)

    Barnett, Richard C.; Bhattacharya, Joydeep; Bunzel, Helle

    equilibria because they asymptotically violate some economic restriction of the model. The literature has always ruled out such paths. This paper studies a pure-exchange monetary overlapping generations economy in which real balances cycle forever between momentary equilibrium points. The novelty is to show...... that segments of the offer curve that have been previously ignored, can in fact be used to produce asymptotically valid cyclical paths. Indeed, a cycle can bestow dynamic validity on momentary equilibrium points that had erstwhile been classified as dynamically invalid....

  13. 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.

  14. Life Cycle Environmental Management

    DEFF Research Database (Denmark)

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

    1996-01-01

    A precondition for environmentally conscious management is the awareness of the environmental impact potentials created by an industrial company. There is an obvious need for management tools to support the implementation of relevant environmental criteria into the industrial decision making...... 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...... of the complete set of environmental objects in an industrial manufacturing company....

  15. 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....

  16. 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....

  17. 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.

  18. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    2009-01-01

    teacher employment patterns at the state level in Germany and find strong evidence of cycling mechanisms, in the form of electioneering and honeymooning. Against a backdrop of a continuously shrinking total teachers' pool, German state-level incumbents accelerate the hiring of new teachers during election...

  19. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    teacher employment patterns at the state level in Germany and find strong evidence of cycling mechanisms, in the form of electioneering and honeymooning. Against a backdrop of a continuously shrinking total teachers' pool, German state-level incumbents accelerate the hiring of new teachers during election...

  20. 90-Day Cycle Handbook

    Science.gov (United States)

    Park, Sandra; Takahashi, Sola

    2013-01-01

    90-Day Cycles are a disciplined and structured form of inquiry designed to produce and test knowledge syntheses, prototyped processes, or products in support of improvement work. With any type of activity, organizations inevitably encounter roadblocks to improving performance and outcomes. These barriers might include intractable problems at…

  1. ITER fuel cycle

    International Nuclear Information System (INIS)

    Resulting from the Conceptual Design Activities (1988-1990) by the parties involved in the International Thermonuclear Experimental Reactor (ITER) project, this document summarizes the design requirements and the Conceptual Design Descriptions for each of the principal subsystems and design options of the ITER Fuel Cycle conceptual design. The ITER Fuel Cycle system provides for the handling of all tritiated water and gas mixtures on ITER. The system is subdivided into subsystems for fuelling, primary (torus) vacuum pumping, fuel processing, blanket tritium recovery, and common processes (including isotopic separation, fuel management and storage, and processes for detritiation of solid, liquid, and gaseous wastes). After an introduction describing system function and conceptual design procedure, a summary of the design is presented including a discussion of scope and main parameters, and the fuel design options for fuelling, plasma chamber vacuum pumping, fuel cleanup, blanket tritium recovery, and auxiliary and common processes. Design requirements are defined and design descriptions are given for the various subsystems (fuelling, plasma vacuum pumping, fuel cleanup, blanket tritium recovery, and auxiliary/common processes). The document ends with sections on fuel cycle design integration, fuel cycle building layout, safety considerations, a summary of the research and development programme, costing, and conclusions. Refs, figs and tabs

  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. 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…

  4. 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…

  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. Fuel cycle. Fuel reprocessing

    International Nuclear Information System (INIS)

    Reprocessing includes mechanical and chemical operations on spent fuel for extraction of valuable materials. These operations are a part of the fuel cycle. In this paper are given technical data on spent fuels, transport, storage, decladding, dissolution, Purex process, elaboration of U and Pu and reprocessing engineering. This article is completed by 106 references

  7. 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

  8. Efficient Enumeration of Chordless Cycles

    OpenAIRE

    Dias, Elisângela Silva; Castonguay, Diane; Longo, Humberto; Jradi, Walid Abdala Rfaei

    2013-01-01

    In a finite undirected simple graph, a {\\it chordless cycle} is an induced subgraph which is a cycle. We propose two algorithms to enumerate all chordless cycles of such a graph. Compared to other similar algorithms, the proposed algorithms have the advantage of finding each chordless cycle only once. To ensure this, we introduced the concepts of vertex labeling and initial valid vertex triplet. To guarantee that the expansion of a given chordless path will always lead to a chordless cycle, w...

  9. 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.

  10. 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.

  11. 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.

  12. CANDU fuel cycle flexibility

    International Nuclear Information System (INIS)

    High neutron economy, on-power refuelling, and a simple bundle design provide a high degree of flexibility that enables CANDU (Canada Deuterium Uranium; registered trademark) reactors to be fuelled with a wide variety of fuel types. Near-term applications include the use of slightly enriched uranium (SEU), and recovered uranium (RU) from reprocessed spent Light Water Reactor (LWR) fuel. Plutonium and other actinides arising from various sources, including spent LWR fuel, can be accommodated, and weapons-origin plutonium could be destroyed by burning in CANDU. In the DUPIC fuel cycle, a dry processing method would convert spent Pressurized Water Reactor (PWR) fuel to CANDU fuel. The thorium cycle remains of strategic interest in CANDU to ensure long-term resource availability, and would be of specific interest to those countries possessing large thorium reserves, but limited uranium resources. (author). 21 refs

  13. Riding the cycle

    International Nuclear Information System (INIS)

    The current state of the Canadian oil and natural gas industry is reviewed as part of a discussion of economic cycles focusing in particular on the most recent cycle and the impact it has had on the industry. The review of the state of the industry includes discussion of production, exports, commodity prices, the stimulating effect of price increases on the number of oil and natural gas wells drilled, drilling rig operating days. Also discussed are the effect of foreign exchange rates, capital spending, industry financial performance in terms of return on capital employed, the impact of oil and gas prices on Alberta provincial revenues, estimates of Canada's ultimate crude oil and natural gas resources potential, pipelines and pipeline proposals for northern gas, and projection of crude oil and natural gas production in Canada to 2010

  14. A Kalina cycle with ejector

    International Nuclear Information System (INIS)

    A Kalina cycle with ejector (EKalina cycle) is proposed in this paper. In the EKalina cycle, an ejector is used to substitute for the throttle valve and the absorber in the Kalina cycle system 11 (KCS 11). The exhaust pressure of the expander is decreased by the ejector resulted in an increase of the working pressure difference of the expansion, and to increase the power output and the thermal efficiency of the cycle. The thermodynamic analyses and comparisons between the EKalina cycle and the KCS 11 are conducted on the cycle's power output, thermal efficiency with the low-grade heat source (LGHS). Water is chosen as the LGHS fluid, and the same temperature and mass flow rate of the water is the standard condition for the comparative analysis on the EKalina cycle and the KCS 11. Results show that the net power output and thermal efficiency of the EKalina cycle are higher than that of the KCS 11. - Highlights: • A Kalina cycle with ejector (EKalina cycle) based on Kalina cycle system 11 (KCS 11) is proposed. • Substituting ejector for the throttle valve to avoid throttling losses improves the cycle performance. • The net power output and thermal efficiency of EKalina cycle are higher than that of KCS 11

  15. 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.

  16. HCl removal using cycled carbide slag from calcium looping cycles

    International Nuclear Information System (INIS)

    Highlights: • Cycled carbide slag from calcium looping cycles is used to remove HCl. • The optimum temperature for HCl removal of cycled carbide slag is 700 °C. • The presence of CO2 restrains HCl removal of cycled carbide slag. • CO2 capture conditions have important effects on HCl removal of cycled carbide slag. • HCl removal capacity of carbide slag drops with cycle number rising from 1 to 50. - Abstract: The carbide slag is an industrial waste from chlor-alkali plants, which can be used to capture CO2 in the calcium looping cycles, i.e. carbonation/calcination cycles. In this work, the cycled carbide slag from the calcium looping cycles for CO2 capture was proposed to remove HCl in the flue gas from the biomass-fired and RDFs-fired boilers. The effects of chlorination temperature, HCl concentration, particle size, presence of CO2, presence of O2, cycle number and CO2 capture conditions in calcium looping cycles on the HCl removal behavior of the carbide slag experienced carbonation/calcination cycles were investigated in a triple fixed-bed reactor. The chlorination product of the cycled carbide slag from the calcium looping after absorbing HCl is not CaCl2 but CaClOH. The optimum temperature for HCl removal of the cycled carbide slag from the carbonation/calcination cycles is 700 °C. The chlorination conversion of the cycled carbide slag increases with increasing the HCl concentration. The cycled carbide slag with larger particle size exhibits a lower chlorination conversion. The presence of CO2 decreases the chlorination conversions of the cycled carbide slag and the presence of O2 has a trifling impact. The chlorination conversion of the carbide slag experienced 1 carbonation/calcination cycle is higher than that of the uncycled calcined sorbent. As the number of carbonation/calcination cycles increases from 1 to 50, the chlorination conversion of carbide slag drops gradually. The high calcination temperature and high CO2 concentration in the

  17. 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...

  18. Pork Barrel Cycles

    OpenAIRE

    Allan Drazen; Marcela Eslava

    2006-01-01

    We present a model of political budget cycles in which incumbents influence voters by targeting government spending to specific groups of voters at the expense of other voters or other expenditures. Each voter faces a signal extraction problem: being targeted with expenditure before the election may reflect opportunistic manipulation, but may also reflect a sincere preference of the incumbent for the types of spending that voter prefers. We show the existence of a political equilibrium in whi...

  19. The carbon dioxide cycle

    Science.gov (United States)

    James, P.B.; Hansen, G.B.; Titus, T.N.

    2005-01-01

    The seasonal CO2 cycle on Mars refers to the exchange of carbon dioxide between dry ice in the seasonal polar caps and gaseous carbon dioxide in the atmosphere. This review focuses on breakthroughs in understanding the process involving seasonal carbon dioxide phase changes that have occurred as a result of observations by Mars Global Surveyor. ?? 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  20. Recycling and Endogenous Cycles

    OpenAIRE

    Fodha, Mouez; Francesco MAGRIS

    2012-01-01

    This article investigates the conditions under which deterministic cycles can emerge in a discrete-time model with infinitely lived agents and when the economy is characterized by two sectors producing two perfectly substitutable goods: a virgin good and a recycled one. The occurrence of deterministic fluctuations rests upon the countercyclical behavior of the recycling industry: an increase in present consumption implies a lower future waste activity together with a lower agents' total incom...

  1. 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.

  2. 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...

  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. 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.

  5. 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.)

  6. 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.

  7. Bifurcation of limit cycles near equivariant compound cycles

    Institute of Scientific and Technical Information of China (English)

    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.

  8. 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...

  9. 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...

  10. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

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

    1999-01-01

    OBJECTIVE: 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. DESIGN: Prospective follow-up study. SETTING: Healthy couples recruited throughout Denmark...

  11. Fictitious Supercontinent Cycles

    Science.gov (United States)

    Marvin Herndon, J.

    2014-05-01

    "Supercontinent cycles" or "Wilson cycles" is the idea that before Pangaea there were a series of supercontinents that each formed and then broke apart and separated before colliding again, re-aggregating, and suturing into a new supercontinent in a continuing sequence. I suggest that "supercontinent cycles" are artificial constructs, like planetary orbit epicycles, attempts to describe geological phenomena within the framework of problematic paradigms, namely, planetesimal Earth formation and plate tectonics' mantle convection. The so-called 'standard model of solar system formation' is problematic as it would lead to insufficiently massive planetary cores and necessitates additional ad hoc hypotheses such as the 'frost line' between Mars and Jupiter to explain planetary differences and whole-planet melting to explain core formation from essentially undifferentiated matter. The assumption of mantle convection is crucial for plate tectonics, not only for seafloor spreading, but also for continental movement; continent masses are assumed to ride atop convection cells. In plate tectonics, plate collisions are thought to be the sole mechanism for fold-mountain formation. Indeed, the occurrence of mountain chains characterized by folding which significantly predate the breakup of Pangaea is the primary basis for assuming the existence of supercontinent cycles with their respective periods of ancient mountain-forming plate collisions. Mantle convection is physically impossible. Rayleigh Number justification has been misapplied. The mantle bottom is too dense to float to the surface by thermal expansion. Sometimes attempts are made to obviate the 'bottom heavy' prohibition by adopting the tacit assumption that the mantle behaves as an ideal gas with no viscous losses, i.e., 'adiabatic'. But the mantle is a solid that does not behave as an ideal gas as evidenced by earthquakes occurring at depths as great as 660 km. Absent mantle convection, plate tectonics is not valid

  12. The world tourism exports cycle

    OpenAIRE

    Gouveia, Pedro; Guerreiro, Raul Filipe; Paulo M.M. Rodrigues

    2013-01-01

    Considering that tourism is an important industry on a global scale, this study analyses and compares the deviations cycles from the long-term trend of tourism exports for all regions of the world with the cycle of the European Union with 27 member states (EU27). In this context, the approach followed allows us to analyse and determine the synchronization between tourism exports cycles of various regions of interest. In parallel, lagged concordance indices of cycles are id...

  13. GEOSS Water Cycle Integrator

    Science.gov (United States)

    Koike, Toshio; Lawford, Richard; Cripe, Douglas

    2013-04-01

    It is critically important to recognize and co-manage the fundamental linkages across the water-dependent domains; land use, including deforestation; ecosystem services; and food-, energy- and health-securities. Sharing coordinated, comprehensive and sustained observations and information for sound decision-making is a first step; however, to take full advantage of these opportunities, we need to develop an effective collaboration mechanism for working together across different disciplines, sectors and agencies, and thereby gain a holistic view of the continuity between environmentally sustainable development, climate change adaptation and enhanced resilience. To promote effective multi-sectoral, interdisciplinary collaboration based on coordinated and integrated efforts, the intergovernmental Group on Earth Observations (GEO) is implementing the Global Earth Observation System of Systems (GEOSS). A component of GEOSS now under development is the "GEOSS Water Cycle Integrator (WCI)", which integrates Earth observations, modeling, data and information, management systems and education systems. GEOSS/WCI sets up "work benches" by which partners can share data, information and applications in an interoperable way, exchange knowledge and experiences, deepen mutual understanding and work together effectively to ultimately respond to issues of both mitigation and adaptation. (A work bench is a virtual geographical or phenomenological space where experts and managers collaborate to use information to address a problem within that space). GEOSS/WCI enhances the coordination of efforts to strengthen individual, institutional and infrastructure capacities, especially for effective interdisciplinary coordination and integration. GEO has established the GEOSS Asian Water Cycle Initiative (AWCI) and GEOSS African Water Cycle Coordination Initiative (AfWCCI). Through regional, inter-disciplinary, multi-sectoral integration and inter-agency coordination in Asia and Africa, GEOSS

  14. Liquid air cycle engines

    Science.gov (United States)

    Rosevear, Jerry

    1992-01-01

    Given here is a definition of Liquid Air Cycle Engines (LACE) and existing relevant technologies. Heat exchanger design and fabrication techniques, the handling of liquid hydrogen to achieve the greatest heat sink capabilities, and air decontamination to prevent heat exchanger fouling are discussed. It was concluded that technology needs to be extended in the areas of design and fabrication of heat exchangers to improve reliability along with weight and volume reductions. Catalysts need to be improved so that conversion can be achieved with lower quantities and lower volumes. Packaging studies need to be investigated both analytically and experimentally. Recycling with slush hydrogen needs further evaluation with experimental testing.

  15. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    After a short introduction about nuclear power in the world, fission physics and the French nuclear power plants, this brochure describes in a digest way the different steps of the nuclear fuel cycle: uranium prospecting, mining activity, processing of uranium ores and production of uranium concentrates (yellow cake), uranium chemistry (conversion of the yellow cake into uranium hexafluoride), fabrication of nuclear fuels, use of fuels, reprocessing of spent fuels (uranium, plutonium and fission products), recycling of energetic materials, and storage of radioactive wastes. (J.S.)

  16. 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

  17. 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…

  18. Changing global carbon cycle

    International Nuclear Information System (INIS)

    Full text: The increase in atmospheric carbon dioxide (C02) is the single largest human perturbation on the earth's radiative balance contributing to climate change. Its rate of change reflects the balance between anthropogenic carbon emissions and the dynamics of a number of terrestrial and ocean processes that remove or emit C02. It is the long term evolution of this balance that will determine to large extent the speed and magnitude of the human induced climate change and the mitigation requirements to stabilise atmospheric C02 concentrations at any given level. In this talk, we show new trends in global carbon sources and sinks, with particularly focus on major shifts occurring since 2000 when the growth rate of atmospheric C02 has reached its highest level on record. The acceleration in the C02 growth results from the combination of several changes in properties of the carbon cycle, including: acceleration of anthropogenic carbon emissions; increased carbon intensity of the global economy, and decreased efficiency of natural carbon sinks. We discuss in more detail some of the possible causes of the reduced efficiency of natural carbon sinks on land and oceans, such as the decreased net sink in the Southern Ocean and on terrestrial mid-latitudes due to world-wide occurrence of drought. All these changes reported here characterise a carbon cycle that is generating stronger than expected climate forcing, and sooner than expected

  19. Velenje - Mislinja cycle track regulation

    OpenAIRE

    Vidonja, Klemen

    2013-01-01

    In my graduation thesis, I am planning a cycle track from Velenje to Mislinja, where it will be connected to an existing bike track to Otiški vrh. The cycle track would be placed on a deserted railway route from Velenje to Dravograd. A short section of cycle track is already in use, but it has to be repared. I planned the rest of the cycle track and I regulated it in a turist – recreational manner, suitable for all types of riders. The cycle track is placed away from traffic, does not dema...

  20. 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

  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. Nutrient Cycling Study

    Energy Technology Data Exchange (ETDEWEB)

    Peter A. Pryfogle

    2005-09-01

    The particular goal of this study is to develop measurement techniques for understanding how consortia of organisms from geothermal facilities utilize sulfur and iron for metabolic activity; and in turn, what role that activity plays in initiating or promoting the development of a biofilm on plant substrates. Sulfur cycling is of interest because sulfur is produced in the resource. Iron is found in some of the steel formulations used in plant components and is also added as chemical treatment for reducing sulfide emissions from the plants. This report describes the set-up and operation of a bioreactor for evaluating the response of colonies of geothermal organisms to changes in nutrient and environmental conditions. Data from initial experiments are presented and plans for future testing is discussed.

  3. CANDU advanced fuel cycles

    International Nuclear Information System (INIS)

    This report is based on informal lectures and presentations made on CANDU Advanced Fuel Cycles over the past year or so, and discusses the future role of CANDU in the changing environment for the Canadian and international nuclear power industry. The changing perspectives of the past decade lead to the conclusion that a significant future market for a CANDU advanced thermal reactor will exist for many decades. Such a reactor could operate in a stand-alone strategy or integrate with a mixed CANDU-LWR or CANDU-FBR strategy. The consistent design focus of CANDU on enhanced efficiency of resource utilization combined with a simple technology to achieve economic targets, will provide sufficient flexibility to maintain CANDU as a viable power producer for both the medium- and long-term future

  4. 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)

  5. Coupled quantum Otto cycle.

    Science.gov (United States)

    Thomas, George; Johal, Ramandeep S

    2011-03-01

    We study the one-dimensional isotropic Heisenberg model of two spin-1/2 systems as a quantum heat engine. The engine undergoes a four-step Otto cycle where the two adiabatic branches involve changing the external magnetic field at a fixed value of the coupling constant. We find conditions for the engine efficiency to be higher than in the uncoupled model; in particular, we find an upper bound which is tighter than the Carnot bound. A domain of parameter values is pointed out which was not feasible in the interaction-free model. Locally, each spin seems to cause a flow of heat in a direction opposite to the global temperature gradient. This feature is explained by an analysis of the local effective temperature of the spins. PMID:21517482

  6. The nuclear power cycle

    International Nuclear Information System (INIS)

    Fifty years after the first nuclear reactor come on-line, nuclear power is fourth among the world's primary energy sources, after oil, coal and gas. In 2002, there were 441 reactors in operation worldwide. The United States led the world with 104 reactors and an installed capacity of 100,000 MWe, or more than one fourth of global capacity. Electricity from nuclear energy represents 78% of the production in France, 57% in Belgium, 46% in Sweden, 40% in Switzerland, 39% in South Korea, 34% in Japan, 30% in Germany, 30% in Finland, 26% in Spain, 22% in Great Britain, 20% in the United States and 16% in Russia. Worldwide, 32 reactors are under construction, including 21 in Asia. This information document presents the Areva activities in the nuclear power cycle: the nuclear fuel, the nuclear reactors, the spent fuel reprocessing and recycling and nuclear cleanup and dismantling. (A.L.B.)

  7. 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

  8. The Hamburg oceanic carbon cycle circulation model. Cycle 1

    International Nuclear Information System (INIS)

    The carbon cycle model calculates the prognostic fields of oceanic geochemical carbon cycle tracers making use of a 'frozen' velocity field provided by a run of the LSG oceanic circulation model (see the corresponding manual, LSG=Large Scale Geostrophic). The carbon cycle model includes a crude approximation of interactions between sediment and bottom layer water. A simple (meridionally diffusive) one layer atmosphere model allows to calculate the CO2 airborne fraction resulting from the oceanic biogeochemical interactions. (orig.)

  9. Money and Business Cycles: A Real Business Cycle Interpretation

    OpenAIRE

    Charles I. Plosser

    1990-01-01

    This paper focuses on the role of money in economic fluctuations. While money may play an important role in market economies, its role as an important impulse to business cycles remains a highly controversial hypothesis. For years economists have attempted to construct monetary theories of the business cycle with only limited empirical success. Alternatively, recent real theories of the cycle have taken the view that to a first approximation independent variations in the nominal quantity of o...

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

    DEFF Research Database (Denmark)

    Andersen, S. B.; Thomsen, Jon Juel

    2002-01-01

    predicted 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......This study examines how a tip mass with rotary inertia affects the stability of a follower-loaded cantilevered column. Using nonlinear modeling and perturbation analysis, expressions are set up for determining the stability of the straight column and the amplitude of post-critical flutter...... into subcritical. This can imply very large motions for follower loads just beyond critical, contrasting the finite amplitude motions accompanying supercritical bifurcations. Also, the straight column may be destabilized by a sufficiently strong disturbance at loads far below the value of critical load...

  11. 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

  12. 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.

  13. 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

  14. Life cycle of mobile devices

    OpenAIRE

    T.V. Rohal; S.I. Naumenko; G.О Peresadko

    2011-01-01

    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 i...

  15. 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, ...

  16. 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.

  17. 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.

  18. Fast reactor fuel cycle facility

    International Nuclear Information System (INIS)

    An integrated fuel cycle facility named Fast Reactor Fuel Cycle Facility (FRFCF) is planned to be set up at Kalpakkam to close the fuel cycle of the Prototype Fast Breeder Reactor (PFBR) that is already under construction there. FRFCF is the first project of its kind in India. Closure of fuel cycle of PFBR will be a significant milestone of the second stage of nuclear power programme of the Department of Atomic Energy. The facility would be ready for operation in 2014. Design work and safety review of FRFCF are presently in progress. (author)

  19. 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 ...

  20. 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.

  1. 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)

  2. The nitrogen cycle.

    Science.gov (United States)

    Stein, Lisa Y; Klotz, Martin G

    2016-02-01

    Nitrogen is the fourth most abundant element in cellular biomass, and it comprises the majority of Earth's atmosphere. The interchange between inert dinitrogen gas (N2) in the extant atmosphere and 'reactive nitrogen' (those nitrogen compounds that support, or are products of, cellular metabolism and growth) is entirely controlled by microbial activities. This was not the case, however, in the primordial atmosphere, when abiotic reactions likely played a significant role in the inter-transformation of nitrogen oxides. Although such abiotic reactions are still important, the extant nitrogen cycle is driven by reductive fixation of dinitrogen and an enzyme inventory that facilitates dinitrogen-producing reactions. Prior to the advent of the Haber-Bosch process (the industrial fixation of N2 into ammonia, NH3) in 1909, nearly all of the reactive nitrogen in the biosphere was generated and recycled by microorganisms. Although the Haber-Bosch process more than quadrupled the productivity of agricultural crops, chemical fertilizers and other anthropogenic sources of fixed nitrogen now far exceed natural contributions, leading to unprecedented environmental degradation. PMID:26859274

  3. 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

  4. 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

  5. Otto Hansmann: Jean-Jacques Rousseau (1712–1778). (Basiswissen Pädagogik – Teilbereich Historische Pädagogik, Bd. 1.) Baltmannsweiler: Schneider 2002. 232 S., EUR 16,–. Hartmut von Hentig: Rousseau oder Die wohlgeordnete Freiheit. München: Beck 2003. 124 S., EUR 14,90. Alfred Schäfer: Jean-Jacques Rousseau. Ein pädagogisches Porträt. Weinheim/Basel: Beltz 2002. 156 S., EUR 14,90 [Rezension

    OpenAIRE

    Tenorth, Heinz-Elmar

    2005-01-01

    Sammelrezension zu: Otto Hansmann: Jean-Jacques Rousseau (1712–1778). (Basiswissen Pädagogik – Teilbereich Historische Pädagogik, Bd. 1.) Baltmannsweiler: Schneider 2002. 232 S., EUR 16,–. Hartmut von Hentig: Rousseau oder Die wohlgeordnete Freiheit. München: Beck 2003. 124 S., EUR 14,90. Alfred Schäfer: Jean-Jacques Rousseau. Ein pädagogisches Porträt. Weinheim/Basel: Beltz 2002. 156 S., EUR 14,90

  6. The Level of Anxiety and Depression Among Iranian Infertile Couples Undergoing In Vitro Fertilization or Intra Cytoplasmic Sperm Injection Cycles

    Directory of Open Access Journals (Sweden)

    M Yassini

    2005-11-01

    Full Text Available Background: Approximately 10% of Iranian couples wishing to have a child experience some types of infertility which may impose a considerable psychological burden on them. The main objective of this cross-sectional study was to examine the level of anxiety and depression among infertile couples undergoing IVF or ICSI treatment cycles in Iran. Methods: Fifty infertile couples that who undergoing IVF (n=25 or ICSI (n=25 cycles were considered for this descriptive cross-sectional study. Also, 25 married couples (18-40 years old with history of fertility served as control subjects. All husbands and wives were examined by means of Beck Depression and Spielberger Anxiety Inventories. Results: Comparing with controls, the highest rates of moderate and severe anxiety, were observed in women undergoing IVF (76% and 12%, respectively; P<0.05. However, the rate of depression among women in IVF group was comparable to women undergoing ICSI. Also, the highest rates of severe depression and anxiety were demonstrated among housewives (23.9% and 11%, respectively. The lowest rates of severe anxiety and depression were observed in husbands participated in either IVF or ICSI cycles. In addition, illiterates, compared with educated couples, undergoing IVF or ICSI program were shown to have the highest rates of both depression and anxiety. Conclusion: The results showed that the levels of anxiety and depression were higher in women, especially housewives, undergoing IVF or ICSI cycles than control subjects. Also, men showed lower rates of anxiety and depression than women undergoing IVF or ICSI. Therefore, this can provide useful information and guidance for health professionals working with infertile patients. KeyWords: anxiety, depression, infertility, IVF, ICSI, Iran

  7. 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).

  8. 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

  9. Business Cycles Accounting for Paraguay

    OpenAIRE

    Hnatkovska, Viktoria; Koehler-Geib, Friederike

    2015-01-01

    This study investigates the role of domestic and external shocks in business cycle fluctuations in Paraguay during 1991–2012. Time-series methods and a structural model-based approach are used to conduct an integrated analysis of business cycles. First, structural vector autoregression is used to assess the role played by external factors and domestic shocks in driving fluctuations in gros...

  10. 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,…

  11. Analysis of Sunspot Activity Cycles

    Science.gov (United States)

    Greenkorn, Robert A.

    2009-04-01

    A nonlinear analysis of the daily sunspot number for each of cycles 10 to 23 is used to indicate whether the convective turbulence is stochastic or chaotic. There is a short review of recent papers considering sunspot statistics and solar activity cycles. The differences in the three possible regimes - deterministic laminar flow, chaotic flow, and stochastic flow - are discussed. The length of data sets necessary to analyze the regimes is investigated. Chaos is described and a chronology of recent results that utilize chaos and fractals to analyze sunspot numbers follows. The parameters necessary to describe chaos - time lag, phase space, embedding dimension, local dimension, correlation dimension, and the Lyapunov exponents - are determined for the attractor for each cycle. Assuming the laminar regime is unlikely if chaos is not indicated in a cycle by the calculations, the regime must be stochastic. The sunspot numbers in each of cycles 10 to 19 indicate stochastic behavior. There is a transition from stochastic to chaotic behavior of the sunspot numbers in cycles 20, 21, 22, and 23. These changes in cycles 20 - 23 may indicate a change in the scale of turbulence in the convection zone that could result in a change in the convective heat transfer and a change in the size of the convection region for these four cycles.

  12. 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...

  13. 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.

  14. Corporate governance cycles during transition

    DEFF Research Database (Denmark)

    Jones, Derek C.; Mygind, Niels

    2004-01-01

    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...

  15. Business Cycle Theory before Keynes

    OpenAIRE

    Claude Diebolt

    2009-01-01

    This article is concerned with the development of the theory of business cycles before Keynes. It is impossible to treat fully all the theories or to mention all those who have contributed to the literature. Our main consideration will be the development of cycle theory, with maximum emphasis upon ideas.

  16. 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.

  17. Reciprocating heat-engine cycles

    International Nuclear Information System (INIS)

    The performance of a generalized irreversible reciprocating heat-engine cycle model consisting of two heating branches, two cooling branches and two adiabatic branches with heat-transfer loss and friction-like term loss was analyzed using finite-time thermodynamics. The relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, as well as the optimal relation between the power output and the efficiency of the cycle are derived. Moreover, analysis and optimization of the model were carried out in order to investigate the effect of the cycle process on the performances of the cycles using numerical examples. The results obtained herein include the performance characteristics of irreversible reciprocating Diesel, Otto, Atkinson, Brayton, Dual and Miller cycles

  18. Fuel cycle cost uncertainty from nuclear fuel cycle comparison

    International Nuclear Information System (INIS)

    This paper examined the uncertainty in fuel cycle cost (FCC) calculation by considering both model and parameter uncertainty. Four different fuel cycle options were compared in the analysis including the once-through cycle (OT), the DUPIC cycle, the MOX cycle and a closed fuel cycle with fast reactors (FR). The model uncertainty was addressed by using three different FCC modeling approaches with and without the time value of money consideration. The relative ratios of FCC in comparison to OT did not change much by using different modeling approaches. This observation was consistent with the results of the sensitivity study for the discount rate. Two different sets of data with uncertainty range of unit costs were used to address the parameter uncertainty of the FCC calculation. The sensitivity study showed that the dominating contributor to the total variance of FCC is the uranium price. In general, the FCC of OT was found to be the lowest followed by FR, MOX, and DUPIC. But depending on the uranium price, the FR cycle was found to have lower FCC over OT. The reprocessing cost was also found to have a major impact on FCC

  19. 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.

  20. Limit cycles in quantum systems

    International Nuclear Information System (INIS)

    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/R2-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.

  1. 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

  2. Digital daily cycles of individuals

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...

  3. 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...

  4. 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...

  5. 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.

  6. 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.

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

    International Nuclear Information System (INIS)

    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

  8. Ammonium generation during SRAT cycle

    International Nuclear Information System (INIS)

    During the IDMS noble-metal demonstration runs ammonium nitrate deposition was found in the vessel vent system of the feed preparation area. In the bench-scale experiments of studying the hydrogen generation during the sludge treatment cycle, ammonium ion production was also monitored. It was found that: During a simulation of the DWPF Cold Chemical Runs SRAT cycle no detectable amount of ammonium ions was generated when treating a non-noble-metal containing sludge simulant according to the nitric acid flowsheet. Ammonium ions were generated during the SRAT-SME cycle when treating the noble-metal containing sludge with either formic acid or nitric acid/late-washing PHA. This is due to the reaction between formic acid and nitrate catalyzed by the noble metals in the sludge simulant. Ammonium ion production closely followed the hydrogen evolution from the catalytic decomposition of formic acid. This report summarizes the results of the production of ammonia during the SRAT cycle

  9. Optimisation of the nominal cycle

    CERN Document Server

    Redaelli, S

    2011-01-01

    The energy ramp and the betatron squeeze are critical phases of the LHC operation. During the squeeze, delicate optics manipulations take place when the stored energy is maximum. In 2010, ramp and squeeze were commissioned rapidly and smoothly became operational. On the other hand, during the first commissioning exercise, the focus was put on machine safety and on operational robustness rather then in efficiency for luminosity production. After having accumulated a full year of experience on the operational cycle and having gained important feedback on machine behaviour and operational procedures, it is now time to address the optimization of the LHC cycle, while still respecting safe boundaries. In this paper, the experience with the LHC operational cycle is reviewed, possible bottlenecks are identified and paths for improvements are addressed. Proposals for improvement are based on a critical look at the limiting factors encountered in the different phases of the cycle. More complex operation configurations...

  10. 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.

  11. 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...

  12. (Auto)Ethnographies and Cycling

    DEFF Research Database (Denmark)

    Larsen, Jonas

    2014-01-01

    This article discusses the formation, salience and reformation of everyday bodily routines and resources in relation to cycling; it also examines how we can study them ethnographically in different places. I discuss forms of embodied, sensuous and mobile ethnography that can illuminate how routines......, 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...

  13. DIPS power conversion cycle selection

    International Nuclear Information System (INIS)

    This paper presents the results of the dynamic power conversion cycle selection process conducted by the Rocketdyne Division of Rockwell International as part of the Dynamic Isotope Power Subsystem (DIPS) Program, sponsored by the U.S. Department of Energy (DOE). Rocketdyne is under contract with DOE for the DIPS Program. The objective of the DIPS Program is to demonstrate the technology necessary to provide dynamic radioisotope space electrical power systems in the 1 to 10 kWe range to support evolving military and civilian missions in the early 1990s and beyond. Selecting the most appropriate DIPS power conversion cycle that would support this objective was an integral step in this process. The closed Brayton cycle was selected as the preferred power conversion cycle for the DIPS Program based on an evaluation of several key areas concerning spacecraft power systems performance

  14. Cell cycle control in Alphaproteobacteria.

    Science.gov (United States)

    Collier, Justine

    2016-04-01

    Alphaproteobacteria include many medically and environmentally important organisms. Despite the diversity of their niches and lifestyles, from free-living to host-associated, they usually rely on very similar mechanisms to control their cell cycles. Studies on Caulobacter crescentus still lay the foundation for understanding the molecular details of pathways regulating DNA replication and cell division and coordinating these two processes with other events of the cell cycle. This review highlights recent discoveries on the regulation and the mode of action of conserved global regulators and small molecules like c-di-GMP and (p)ppGpp, which play key roles in cell cycle control. It also describes several newly identified mechanisms that modulate cell cycle progression in response to stresses or environmental conditions. PMID:26871482

  15. 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...

  16. 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,...

  17. 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...

  18. 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.

  19. Grown-up business cycles

    OpenAIRE

    Pugsley, Benjamin; Şahin, Ayşegül

    2014-01-01

    We document two striking facts about U.S. firm dynamics and interpret their significance for aggregate employment dynamics. The first observation is the steady decline in the firm entry rate over the last thirty years, and the second is the gradual shift of employment from younger to older firms over the same period. Both observations hold across industries and geographies. We show that, despite these trends, firms' life-cycle dynamics and business-cycle properties have remained virtually unc...

  20. 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...

  1. New Relationship in Carbon Cycle

    OpenAIRE

    Aleksei Naumov

    2012-01-01

    The problem of carbon dioxide accumulation in the atmosphere is closely related to the biological carbon cycle processes insufficiently studied from the global viewpoint. Based on data obtained from the literature on net primary production (NPP) and soil respiration (SR) of world ecosystems, a quantitative analysis of the relationship between these basic parameters of the production/destruction phase of the carbon cycle is offered in this paper. A direct correspondence (equality in carbon equ...

  2. 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...

  3. 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...

  4. 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...

  5. Muscular & mechanical efficiency in cycling

    OpenAIRE

    Blake, Oliver Malcolm

    2011-01-01

    In cycling some muscle coordination patterns result in high power outputs whereas others are more efficient. This study examined mechanical factors that affect muscle activity to identify coordination patterns used for different power outputs, total muscle activation and muscle activation effectiveness to produce power in cycling. Electromyography, pedal forces, kinematics, power output, cadence and slope were measured and compared indoors and/or outdoors in competitive cyclists at a range of...

  6. 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 ...

  7. 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.

  8. 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)

  9. Thorium fuel cycles in CANDU

    International Nuclear Information System (INIS)

    In recent years, Atomic Energy of Canada Limited has been examining in detail the implications of using thorium-based fuels tn the CANDU reactor. Various cycles initiated and enriched either with fissile plutonium or with enriched uranium, and with effective conversion ratios ranging up to 1.0, have been evaluated. We have concluded that: 1. Substantial quantities of uranium can be saved by adoption of the thorium fuel cycle, and the long-term security of fissile supply both for the domestic and overseas market can be considerably enhanced. The amount saved will depend on the details of the fuel cycle and the anticipated growth of nuclear power in Canada. 2. The fuel cycle can be introduced into the basic CANDU design without major modifications and without compromising current safety standards. 3. The economic conditions that make thorium competitive with the once-through natural uranium cycle depend a the price of uranium and on the costs both to fabricate α and γ-emitting fuels and to either enrich uranium or to extract fissile material from spent fuel. While timing is difficult to predict, we believe that competitive economic conditions will prevail toward the end of this century. 4. A twenty-year technological development program will be required to establish commercial confidence in the fuel cycle. (author)

  10. 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.

  11. Thermodynamic Cycles--One More Time.

    Science.gov (United States)

    Nolan, Michael J.

    1995-01-01

    Discusses interesting aspects of the Carnot cycle and other thermodynamic cycles that are generally not dealt with in elementary physics texts. Presents examples that challenge the student to think about the extraction of net work from a cycle. (JRH)

  12. Binary Brayton cycle with two isothermal processes

    International Nuclear Information System (INIS)

    Highlights: • This paper presents binary Brayton cycle with two isothermal processes. • Different parameters affecting the cycle performance have been studied. • The present cycle is a promising cycle for future power generation. - Abstract: The literature introduced isothermal concept and binary Brayton cycle as two promising methods used to enhance the performance of the gas turbine. Consequently, this work presents a cycle based on the blending of the two methods. This cycle is composed of gas turbine topping cycle with isothermal combustion and air turbine bottoming cycle with isothermal heating. Different parameters affecting the cycle performance have been studied. Simulations demonstrate that the present cycle achieves drastic enhancement in performance. The cycle merits justify its potential utilization for future power generation

  13. The British cycling economy: 'gross cycling product' report

    OpenAIRE

    Grous, Alexander

    2011-01-01

    We believe this is the first-ever attempt to chart the full extent of cycling’s contribution to the British economy. Previous studies have focused on particular sectors such as the bicycle retail trade, but never before has a study been conducted into the true ‘Gross Cycling Product’ (GCP) of UK plc – from bike sales to improved health. The GCP report was conceived by Sky and British Cycling and has been made a reality through the London School of Economics. We commissioned the report, t...

  14. Optimal Life Cycle Portfolio Choice with Housing Market Cycles

    DEFF Research Database (Denmark)

    Fischer, Marcel; Stamos, Michael Z.

    2013-01-01

    In recent decades U.S. households have experienced residential house prices moving persistently, that is, returns being positively serially correlated. We set up a realistically calibrated life cycle model with slow-moving time variation in expected housing returns, showing that not only age, labor...... 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 of...

  15. Candu fuel and fuel cycles

    International Nuclear Information System (INIS)

    A primary rationale for Indonesia to proceed with a nuclear power program is to diversity its energy sources and achieve freedom from future resource constraints. While other considerations, such as economy of power supply, hedging against potential future increases in the price of fossil fuels, fostering the technological development of the Indonesia economy and minimizing greenhouse and other gaseous emissions are important, the strategic resource issue is key. In considering candidate nuclear power technologies upon which to base such a program, a major consideration will be the potential for those technologies to be economically sustained in the face of large future increases in demand for nuclear fuels. The technology or technologies selected should be amenable to evaluation in a rapidly changing technical, economic, resource and environmental policy. The world's proven uranium resources which can be economically recovered represent a fairly modest energy resource if utilization is based on the currently commercialized fuel cycles, even with the use of recovered plutonium in mixed oxide fuels. In the long term, fuel cycles relying solely on the use of light water reactors will encounter increasing fuel supply constraints. Because of its outstanding neutron economy and the flexibility of on-power refueling, CANDU reactors are the most fuel resource efficient commercial reactors and offer the potential for accommodating an almost unlimited variety of advanced and even more fuel efficient cycles. Most of these cycles utilize nuclear fuels which are too low grade to be used in light water reactors, including many products now considered to be waste, such as spent light water reactor fuel and reprocessing products such as recovered uranium. The fuel-cycle flexibility of the CANDU reactor provides a ready path to sustainable energy development in both the short and the long terms. Most of the potential CANDU fuel cycle developments can be accommodated in existing

  16. 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.

  17. Answering Key Fuel Cycle Questions

    International Nuclear Information System (INIS)

    Given the range of fuel cycle goals and criteria, and the wide range of fuel cycle options, how can the set of options eventually be narrowed in a transparent and justifiable fashion? It is impractical to develop all options. We suggest an approach that starts by considering a range of goals for the Advanced Fuel Cycle Initiative (AFCI) and then posits seven questions, such as whether Cs and Sr isotopes should be separated from spent fuel and, if so, what should be done with them. For each question, we consider which of the goals may be relevant to eventually providing answers. The AFCI program has both ''outcome'' and ''process'' goals because it must address both waste already accumulating as well as completing the fuel cycle in connection with advanced nuclear power plant concepts. The outcome objectives are waste geologic repository capacity and cost, energy security and sustainability, proliferation resistance, fuel cycle economics, and safety. The process objectives are rea diness to proceed and adaptability and robustness in the face of uncertainties

  18. 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

  19. 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

  20. 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.

  1. Endogenous, Imperfectly Competitive Business Cycles

    DEFF Research Database (Denmark)

    Whitta-Jacobsen, Hans Jørgen

    below -½ (at stationary equilibrium). Market power on the labor markets may have the effect that imperfectly competitive cycles are in accordance with certain empirical regularities (some well known, some reported in the paper) concerning fluctuations in output and involuntary unemployment. Since......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...

  2. Corporate governance cycles during transition

    DEFF Research Database (Denmark)

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

    2004-01-01

    -ing or exit stage. During transition the cycle reflects: privatization often with a high proportion of employee ownership like in Russia and in Slovenia; strong pressures for restructuring and owner-ship changes; limited possibility for external finance because of embryonic development of the fi......-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...... 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....

  3. 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)

  4. 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.

  5. CANDU fuel-cycle vision

    International Nuclear Information System (INIS)

    The fuel-cycle path chosen by a particular country will depend on a range of local and global factors. The CANDU reactor provides the fuel-cycle flexibility to enable any country to optimize its fuel-cycle strategy to suit its own needs. AECL has developed the CANFLEX fuel bundle as the near-term carrier of advanced fuel cycles. A demonstration irradiation of 24 CANFLEX bundles in the Point Lepreau power station, and a full-scale critical heat flux (CHF) test in water are planned in 1998, before commercial implementation of CANFLEX fuelling. CANFLEX fuel provides a reduction in peak linear element ratings, and a significant enhancement in thermalhydraulic performance. Whereas natural uranium fuel provides many advantages, the use of slightly enriched uranium (SEU) in CANDU reactors offers even lower fuel-cycle costs and other benefits, such as uprating capability through flattening the channel power distribution across the core. Recycled uranium (RU) from reprocessing spent PWR fuel is a subset of SEU that has significant economic promise. AECL views the use of SEU/RU in the CANFLEX bundle as the first logical step from natural uranium. High neutron economy enables the use of low-fissile fuel in CANDU reactors, which opens up a spectrum of unique fuel-cycle opportunities that exploit the synergism between CANDU reactors and LWRs. At one end of this spectrum is the use of materials from conventional reprocessing: CANDU reactors can utilize the RU directly without re-enrichment, the plutonium as conventional Mixed-oxide (MOX) fuel, and the actinide waste mixed with plutonium in an inert-matrix carrier. At the other end of the spectrum is the DUPIC cycle, employing only thermal-mechanical processes to convert spent LWR fuel into CANDU fuel, with no purposeful separation of isotopes from the fuel, and possessing a high degree of proliferation resistance. Between these two extremes are other advanced recycling options that offer particular advantages in exploiting the

  6. CANDU fuel-cycle vision

    International Nuclear Information System (INIS)

    The fuel-cycle path chosen by a particular country will depend on a range of local and global factors. The CANDU reactor provides the fuel-cycle flexibility to enable any country to optimize its fuel-cycle strategy to suit its own needs. AECL has developed the CANFLEX fuel bundle as the near-term carrier of advanced fuel cycles. A demonstration irradiation of 24 CANFLEX bundles in the Point Lepreau power station, and a full-scale critical heat flux (CHF) test in water are planned in 1998, before commercial implementation of CANFLEX fuelling. CANFLEX fuel provides a reduction in peak linear element ratings, and a significant enhancement in thermalhydraulic performance. Whereas natural uranium fuel provides many advantages, the use of slightly enriched uranium (SEU) in CANDU reactors offers even lower fuel-cycle costs and other benefits, such as uprating capability through flattening the channel power distribution across the core. Recycled uranium (RU) from reprocessing spent PWR fuel is a subset of SEU that has significant economic promise. AECL views the use of SEU/RU in the CANFLEX bundle as the first logical step from natural uranium. High neutron economy enables the use of low-fissile fuel in CANDU reactors, which opens up a spectrum of unique fuel-cycle opportunities that exploit the synergism between CANDU reactors and LWRs. At one end of this spectrum is the use of materials from conventional reprocessing: CANDU reactors can utilize the RU directly without reenrichment, the plutonium as conventional mixed-oxide (MOX) fuel, and the actinide waste mixed with plutonium in an inert-matrix carrier. At the other end of the spectrum is the DUPIC cycle, employing only thermal-mechanical processes to convert spent LWR fuel into CANDU fuel, with no purposeful separation of isotopes from the fuel, and possessing a high degree of proliferation resistance. Between these two extremes are other advanced recycling options that offer particular advantages in exploiting the

  7. 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...... 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...... urban settings and small towns. Thus, the way in which travel modes relate to the urban environment and variations in modality styles must serve as the starting point for policies aiming to fulfil the potential of multimodal transport behaviour and promote cycling....

  8. 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)

  9. 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.

  10. 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.

  11. Fuel cycle math - part two

    International Nuclear Information System (INIS)

    This article is Part 2 of a two part series on simple mathematics associated with the nuclear fuel cycle. While not addressing any of the financial aspects of the fuel cycle, this article does discuss the following: conversion between English and metric systems; uranium content expressed in equivalent forms, such as U3O8, and the method of determining these equivalencies; the uranium conversion process, considering different input and output compounds; and the enrichment process, including feed, tails, and product assays, as well as SWU and feed requirements

  12. 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...

  13. 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.

  14. 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.

  15. WWER-1000 fuel cycle improvement

    International Nuclear Information System (INIS)

    The problems of organization of fuel cycles with different operation time of stationary load for the reactor WWER-1000 are considered. The outcomes of matching of the characteristics for stationary load constructed on fuel cells of existing and improved designs are presented. Improved designs of a fuel cell are include increase of an altitude of a fuel stake, change of outside and axial diameters of a fuel pellet, change thickness of a cladding of a fuel cell. Effect of the layout solutions on improving of a fuel cycle WWER-1000 also considered (Authors)

  16. Long operating cycle simplified BWR

    International Nuclear Information System (INIS)

    Considering next generation requirement for nuclear plants, a long cycle operating simplified BWR (LSBWR) concept is proposed. The major features of LSBWR are; 1) Long cycle operation core using uranium fuels; 2) Simplified system and component as well as passive systems; 3) Combined building concept with ship hull structure. This concept have potential to reduce construction cost and to Increase availability. Safety feature of LSBWR makes possible to attain no evacuation capability in case of a severe accident. Further research and development is underway. (author)

  17. 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

  18. 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.

  19. 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 ...

  20. IAEA activities on nuclear fuel cycle 1997

    International Nuclear Information System (INIS)

    The presentation discussing the IAEA activities on nuclear fuel cycle reviews the following issues: organizational charts of IAEA, division of nuclear power and the fuel cycle, nuclear fuel cycle and materials section; 1997 budget estimates; budget trends; the nuclear fuel cycle programme

  1. 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.

  2. On polytropic cycles in finite time

    International Nuclear Information System (INIS)

    Efficiencies at maximum power regime for Stirling and Ericsson cycles are calculated. The Curzon and Ahlborn formula, for efficiency of a Carnot cycle at finite time, for such cycles is obtained also. A theorem for ideal gas polytropic cycles is proposed (Author)

  3. 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…

  4. Time Cycles in Indian Cosmology

    OpenAIRE

    Narayan, R. H.

    2007-01-01

    In this article we review some key time cycles in ancient Indian astronomy, especially those that have emerged from researches in the past couple of decades expressing knowledge of the changing frame of earth's axis. The article also briefly reviews the philosophy related to the interconnection between the inner and the outer cosmos that was used in the analytical narrative related to this astronomy.

  5. Dynamics of the carbon cycle

    International Nuclear Information System (INIS)

    The short article describes the development of the increase in atmospheric CO2 in the past 35 years. The interdependence between CO2 levels and changes in fuel consumption is discussed, but other contributing cycles are discussed as well, e.g. enhanced timber production, ocean warming, reverse ocean currents in the South Pacific. (VHE)

  6. Sourcing Life Cycle Inventory Data

    Science.gov (United States)

    The collection and validation of quality lifecycle inventory (LCI) data can be the most difficult and time-consuming aspect of developing a life cycle assessment (LCA). Large amounts of process and production data are needed to complete the LCI. For many studies, the LCA analyst ...

  7. 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.

  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. 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.)

  10. 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...

  11. Combined cycle power plant Skopje

    International Nuclear Information System (INIS)

    Regarding the new directions in constructing combined cycle power plants, in this work an idea of such plant in Skopje with power of 190 MW has been elaborated. This plant will be constructed on the site of the existing TPP 'Energetika', AD ESM. The rates of efficiency for different condition of operation has been estimated. (Author)

  12. The Passive Aggressive Conflict Cycle

    Science.gov (United States)

    Whitson, Signe

    2013-01-01

    Understanding the Passive Aggressive Conflict Cycle (PACC) helps observers to be able to look beyond behavior and better understand what is occurring beneath the surface. This article presents a real-life example of a seemingly minor conflict between a teacher and child that elicited an apparent major overreaction by the adult. Also provided is a…

  13. 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.

  14. 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.)

  15. 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.

  16. The Timing of the Cognitive Cycle

    OpenAIRE

    Madl, Tamas; Baars, Bernard J.; Franklin, Stan

    2011-01-01

    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 LI...

  17. Evaluation, Generation, and Transformation of Driving Cycles

    OpenAIRE

    Nyberg, Peter

    2015-01-01

    Driving cycles are important components for evaluation and design of vehicles. They determine the focus of vehicle manufacturers, and indirectly they affect the environmental impact of vehicles since the vehicle control system is usually tuned to one or several driving cycles. Thus, the driving cycle affects the design of the vehicle since cost, fuel consumption, and emissions all depend on the driving cycle used for design. Since the existing standard driving cycles cannot keep up with the c...

  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...... 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 and...... engineering design - it seems that the two approaches are complimentary. The principle behind PSS is a shift from a perception that value is mainly embedded in a physical artefact to a perception where the activities associated with the product are considered to be a better definition of value. In this new...

  20. 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...

  1. Multi-cycle boiling water reactor fuel cycle optimization

    Energy Technology Data Exchange (ETDEWEB)

    Ottinger, K.; Maldonado, G.I. [University of Tennessee, 311 Pasqua Engineering Building, Knoxville, TN 37996-2300 (United States)

    2013-07-01

    In this work a new computer code, BWROPT (Boiling Water Reactor Optimization), is presented. BWROPT uses the Parallel Simulated Annealing (PSA) algorithm to solve the out-of-core optimization problem coupled with an in-core optimization that determines the optimum fuel loading pattern. However it uses a Haling power profile for the depletion instead of optimizing the operating strategy. The result of this optimization is the optimum new fuel inventory and the core loading pattern for the first cycle considered in the optimization. Several changes were made to the optimization algorithm with respect to other nuclear fuel cycle optimization codes that use PSA. Instead of using constant sampling probabilities for the solution perturbation types throughout the optimization as is usually done in PSA optimizations the sampling probabilities are varied to get a better solution and/or decrease runtime. The new fuel types available for use can be sorted into an array based on any number of parameters so that each parameter can be incremented or decremented, which allows for more precise fuel type selection compared to random sampling. Also, the results are sorted by the new fuel inventory of the first cycle for ease of comparing alternative solutions. (authors)

  2. 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

  3. 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)

  4. 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).

  5. 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.

  6. 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.

  7. 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.

  8. 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)

  9. 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

  10. 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

  11. Fuel cycle math - part one

    International Nuclear Information System (INIS)

    This article is Part One of a two-part article that reviews some of the numbers associated with the nuclear fuel cycle. The contents of Part One include: composition of the element uranium, considering atomic mass and weight-percent of the isotopes; uranium in the ground, including ore grades; mining, with dilution factors and recovery rates; ore sorting, including concentration factors; and uranium recovery. No financial information is presented in either Part One or Part Two

  12. 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...

  13. 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...

  14. 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)

  15. 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...

  16. Accounting for Spanish business cycles.

    OpenAIRE

    Jesús Rodríguez-López; Mario Solís-García

    2014-01-01

    We apply the business cycle methodology proposed by Chari, Kehoe, and McGrattan (2007) to identify the sources of Spanish business fluctuations during two outstanding cyclical episodes: the recession alongside the transition to democracy in 1977 and the great recession of 2008. We find that the labor wedge plays a key role during both recessions and that taxes and labor market institutions are likely behind the wedge movements. We conclude that any model that tries to understand the causes of...

  17. 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...

  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. Business Cycle Synchronization in Croatia

    OpenAIRE

    Šergo Zdravko; Poropat Amorino; Gržinić Jasmina

    2012-01-01

    The purpose of this paper is to analyze business cycle synchronization in the Croatian economy using various annualized growth rate variables over a period of eighteen years (1992-2010), de-trended by a Hodrick-Prescott filter, and following the Harding and Pagan methodological procedure in the determination of its turning points. Our conceptual analysis of synchronization is based on the technique of concordance indexes and correlation coefficients obtained by the HAC estimators. The main re...

  20. Business cycle dependent unemployment insurance

    OpenAIRE

    Andersen, Torben M.; Svarer, Michael

    2010-01-01

    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 argument. Since benefits may be less distortionary in a recession than a boom, it follows that counter-cyclical benefits reduce average distortions compared to state independent benefits. We show t...

  1. 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...

  2. 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...

  3. 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...

  4. 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

  5. The Life Cycle Analysis Toolbox

    International Nuclear Information System (INIS)

    The life cycle analysis toolbox is a valuable integration of decision-making tools and supporting materials developed by Oak Ridge National Laboratory (ORNL) to help Department of Energy managers improve environmental quality, reduce costs, and minimize risk. The toolbox provides decision-makers access to a wide variety of proven tools for pollution prevention (P2) and waste minimization (WMin), as well as ORNL expertise to select from this toolbox exactly the right tool to solve any given P2/WMin problem. The central element of the toolbox is a multiple criteria approach to life cycle analysis developed specifically to aid P2/WMin decision-making. ORNL has developed numerous tools that support this life cycle analysis approach. Tools are available to help model P2/WMin processes, estimate human health risks, estimate costs, and represent and manipulate uncertainties. Tools are available to help document P2/WMin decision-making and implement programs. Tools are also available to help track potential future environmental regulations that could impact P2/WMin programs and current regulations that must be followed. An Internet-site will provide broad access to the tools

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Optimization of data life cycles

    International Nuclear Information System (INIS)

    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.

  14. Forging the anthropogenic iron cycle.

    Science.gov (United States)

    Wang, Tao; Müller, Daniel B; Graedel, T E

    2007-07-15

    Metallurgical iron cycles are characterized for four anthropogenic life stages: production, fabrication and manufacturing, use, and waste management and recycling. This analysis is conducted for year 2000 and at three spatial levels: 68 countries and territories, nine world regions, and the planet. Findings include the following: (1) contemporary iron cycles are basically open and substantially dependent on environmental sources and sinks; (2) Asia leads the world regions in iron production and use; Oceania, Latin America and the Caribbean, Africa, and the Commonwealth of Independent States present a highly production-biased iron cycle; (3) purchased scrap contributes a quarter of the global iron and steel production; (4) iron exiting use is three times less than that entering use; (5) about 45% of global iron entering use is devoted to construction, 24% is devoted to transport equipment, and 20% goes to industrial machinery; (6) with respect to international trade of iron ore, iron and steel products, and scrap, 54 out of the 68 countries are net iron importers, while only 14 are net exporters; (7) global iron discharges in tailings, slag, and landfill approximate one-third of the iron mined. Overall, these results provide a foundation for studies of iron-related resource policy, industrial development, and waste and environmental management. PMID:17711233

  15. 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.

  16. Solar Cycle 24: Where are you?

    Science.gov (United States)

    Chapman, Gary A.; Cookson, A.; Preminger, D.

    2009-05-01

    Photometric images have been obtained on a daily basis since 1986 at the San Fernando Observatory. We will compare sunspot and facular areas from cycle 22 with those of cycle 23. Both spot areas and facular areas were lower during the maximum of cycle 23 compared to cycle 22. The distribution in spot areas will be compared. The extended minimum in spot area following cycle 23 is delaying the beginning of cycle 24. This work has been partially supported by NSF grant ATM-0533511.

  17. On The Cycle Double Cover Problem

    CERN Document Server

    Ghassab, Ali

    2012-01-01

    In this paper, for each graph G, a free edge set F is defined. To study the existence of cycle double cover, the naive cycle double cover of G and F have been defined and studied. In the main theorem, the paper, based on the Kuratowski minor properties, presents a condition to guarantee the existence of a naive cycle double cover for couple (G,F). As a result, the cycle double cover conjecture has been concluded. Moreover, Goddyn's conjecture - asserting if C is a cycle in bridgeless graph G, there is a cycle double cover of G containing C - will have been proved.

  18. The nuclear fuel cycle; Le cycle du combustible nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    After a short introduction about nuclear power in the world, fission physics and the French nuclear power plants, this brochure describes in a digest way the different steps of the nuclear fuel cycle: uranium prospecting, mining activity, processing of uranium ores and production of uranium concentrates (yellow cake), uranium chemistry (conversion of the yellow cake into uranium hexafluoride), fabrication of nuclear fuels, use of fuels, reprocessing of spent fuels (uranium, plutonium and fission products), recycling of energetic materials, and storage of radioactive wastes. (J.S.)

  19. VVER fuel cycle development at Slovakia

    International Nuclear Information System (INIS)

    Four VVER-440 units are now under exploitation at Bohunice-site in Slovakia. Fuel cycle development of Unit No.3 and No.4 (type 213) is discussed and compared with equilibrium cycles in this paper. (author)

  20. 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.

  1. Development Plan for the Fuel Cycle Simulator

    International Nuclear Information System (INIS)

    The Fuel Cycle Simulator (FCS) project was initiated late in FY-10 as the activity to develop a next generation fuel cycle dynamic analysis tool for achieving the Systems Analysis Campaign 'Grand Challenge.' This challenge, as documented in the Campaign Implementation Plan, is to: 'Develop a fuel cycle simulator as part of a suite of tools to support decision-making, communication, and education, that synthesizes and visually explains the multiple attributes of potential fuel cycles.'

  2. An introduction to global carbon cycle management

    Science.gov (United States)

    Sundquist, Eric T.; Ackerman, Katherine V.; Parker, Lauren; Huntzinger, Deborah N.

    2009-01-01

    Past and current human activities have fundamentally altered the global carbon cycle. Potential future efforts to control atmospheric CO2 will also involve significant changes in the global carbon cycle. Carbon cycle scientists and engineers now face not only the difficulties of recording and understanding past and present changes but also the challenge of providing information and tools for new management strategies that are responsive to societal needs. The challenge is nothing less than managing the global carbon cycle.

  3. Oconee 1, cycle 5 design report

    International Nuclear Information System (INIS)

    The Oconee 1, cycle 5 fuel cycle was designed to irradiate five fuel assemblies to a burnup of approximately 40,000 MWd/mtU. The fuel cycle design was performed using standard Babcock and Wilcox calculational techniques for nuclear fuel cycles. All applicable design criteria were satisfied. Valuable experimental data on the performance characteristics of high-burnup fuel assemblies will be obtained from these assemblies in subsequent post-irradiation examinations

  4. Seasonality and equilibrium business cycle theories

    OpenAIRE

    R. Anton Braun; Evans, Charles L.

    1991-01-01

    Barksy-Miron [1989] find that the postwar U.S. economy exhibits a regular seasonal cycle, as well as the business cycle phenomenon. Are these findings consistent with current equilibrium business cycle theories as surveyed by Prescott [1986]? We consider a dynamic, stochastic equilibrium business cycle model which includes deterministic seasonals and nontime-separable preferences. We show how to compute a perfect foresight seasonal equilibrium path for this economy. An approximation to the st...

  5. Population crises and population cycles.

    Science.gov (United States)

    Russell, C; Russell, W M

    2000-01-01

    To prevent a population irretrievably depleting its resources, mammals have evolved a behavioural and physiological response to population crisis. When a mammalian population becomes dangerously dense, there is a reversal of behaviour. Co-operation and parental behaviour are replaced by competition, dominance and aggressive violence, leading to high mortality, especially of females and young, and a reduced population. The stress of overpopulation and the resulting violence impairs both the immune and the reproductive systems. Hence epidemics complete the crash of the population, and reproduction is slowed for three or four generations, giving the resources ample time to recover. In some mammal species, crisis and crisis response recur regularly, leading to cycles of population growth and relapse, oscillating about a fixed mean. Population crisis response and population cycles have been equally prominent in the history of human societies. But in man successive advances in food production have made possible growing populations, though with every such advance population soon outgrew resources again. Hence human cycles have been superimposed on a rising curve, producing a saw-tooth graph. Because advances in food production amounted to sudden disturbances in the relations between human populations and their environments, the crisis response in man has failed to avert famine and resource damage. In the large human societies evolved since the coming of settled agriculture and cities, the basic effects of violence, epidemics, famine and resource damage have been mediated by such specifically human disasters as inflation, unemployment, and political tyranny. An account of past crises, periods of relative relief from population pressure, and resulting cycles, is given for a number of regions: China, North Africa and Western Asia, the northern Mediterranean, and north-western Europe. The paper ends with an account of the present world-wide population crisis, and the solution

  6. 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 earlier...... 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....

  7. Radioecology of nuclear fuel cycles

    International Nuclear Information System (INIS)

    This study provides information to help assess the environmental impacts and certain potential 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. 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

  8. Carnot cycle for an oscillator

    OpenAIRE

    Arnaud, J.; Chusseau, L.; Philippe, F.

    2001-01-01

    Carnot established in 1824 that the efficiency of cyclic engines operating between a hot bath at absolute temperature $T_{hot}$ and a bath at a lower temperature $T_{cold}$ cannot exceed $1-T_{cold}/T_{hot}$. We show that linear oscillators alternately in contact with hot and cold baths obey this principle in the quantum as well as in the classical regime. The expression of the work performed is derived from a simple prescription. Reversible and non-reversible cycles are illustrated. The pape...

  9. A Coupled Quantum Otto Cycle

    OpenAIRE

    Thomas, George; Johal, Ramandeep S.

    2010-01-01

    We study the 1-d isotropic Heisenberg model of two spin-1/2 systems as a quantum heat engine. The engine undergoes a four-step Otto cycle where the two adiabatic branches involve changing the external magnetic field at a fixed value of the coupling constant. We find conditions for the engine efficiency to be higher than the uncoupled model; in particular, we find an upper bound which is tighter than the Carnot bound. A new domain of parameter values is pointed out which was not feasible in th...

  10. New technology and fuel cycles

    International Nuclear Information System (INIS)

    The means of improving uranium utilization in nuclear power reactors are reviewed with respect to economic considerations, assurance of adequate fuel supplies and risk of weapons proliferation. Reference is made to what can be done to improve fuel economy in existing reactor systems operating on a once-through fuel cycle and the potential for improvement offered by fuel recycle in those systems. The state of development of new reactor systems that offer significant savings in uranium utilization is also reviewed and conclusions are made respecting the policy implications of the search for fuel economy. (author)

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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…

  17. Aspects of the fast reactors fuel cycle

    International Nuclear Information System (INIS)

    The fuel cycle for fast reactors, is analysed, regarding the technical aspects of the developing of the reprocessing stages and the fuel fabrication. The environmental impact of LMFBRs and the waste management of this cycle are studied. The economic aspects of the fuel cycle, are studied too. Some coments about the Brazilian fast reactors programs are done. (E.G.)

  18. The benefits of getting England cycling

    OpenAIRE

    Crawford, F; Lovelace, R

    2015-01-01

    This report compares the economic benefits of achieving the ambitions for cycling proposed in the Cycling Development Plan and the 'Get Britain Cycling' report against a zero-growth baseline. Monetary estimates of the benefits to health, the environment, safety and congestion are presented for the period 2015 to 2050.

  19. 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

  20. VVER-1000 at KNPP - nuclear fuel cycle

    International Nuclear Information System (INIS)

    Information about the realized fuel cycles in the Kozloduy NPP units 5 and 6 is presented - fuel assemblies, fuel maps, transition from 2 years fuel cycle to 3 years fuel cycle, main characteristics of the fueling, combustion depth. Some possibilities for improvements of the campaigns and usage of fuels are discussed

  1. Proposal of a nuclear cycle research and development plan in Tokai works. The roadmap from LWR cycle to FBR cycle

    International Nuclear Information System (INIS)

    The Generation-II Project Task Force Team has investigated a research and development plan of a future nuclear fuel cycle in Tokai works for about three months from December 19, 2002. First we have discussed about the present condition of Japanese nuclear fuel cycle and have recognized it as the following. The relation of the technology between the LWR-cycle and the FBR-cycle is not clear. MOX Fuel Use in Light Water Reactors is important to establish technology of the FBR fuel cycle. Radioactive waste disposal issue is urgent. Next we have proposed the three basic policies on R and D plan of nuclear fuel cycle in consideration of the F.S. on FBR-cycle. Establishment and advancement of 'the tough nuclear fuel cycle'. Early establishment of the FBR cycle technology to be able to supply energy stably for long-term. Establishment of the radioactive waste treatment and disposal technology, and optimization of nuclear fuel cycle technology from the viewpoint of radioactive waste. And we have proposed the Japanese technical holder system to integrate all LWR and FBR cycle technology. (author)

  2. 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

  3. 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.

  4. 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.

  5. Opportunities for fuel cycle development

    International Nuclear Information System (INIS)

    Today the Nuclear Industry is faced with several key challenges, not least that in all it does it has to achieve the highest levels of safety, pursue waste management options acceptable to the industry and general public, operate within varying political climates, and tackle these within a cost regime competitive with fossil fuel generated electricity. These are undoubtedly testing challenges, but on looking to the future there are certain trends which may prove beneficial to the industry and assist in mitigating them - namely that global energy demands are forecast to steadily increase over the next twenty years and beyond, and that in meeting this demand, the desire is to do so with minimal environmental impact. This paper will describe the part nuclear generation can play in servicing future energy demands, how the nuclear resource can best be utilised, how the 'holistic fuel cycle' philosophy can provide a framework for tackling the challenges faced by the industry, and the extent by which international co-operation can support certain advances in the fuel cycle. (author)

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Open-cycle OTEC system performance analysis. [Claude cycle

    Energy Technology Data Exchange (ETDEWEB)

    Lewandowski, A.A.; Olson, D.A.; Johnson, D.H.

    1980-10-01

    An algorithm developed to calculate the performance of Claude-Cycle ocean thermal energy conversion (OTEC) systems is described. The algorithm treats each component of the system separately and then interfaces them to form a complete system, allowing a component to be changed without changing the rest of the algorithm. Two components that are subject to change are the evaporator and condenser. For this study we developed mathematical models of a channel-flow evaporator and both a horizontal jet and spray director contact condenser. The algorithm was then programmed to run on SERI's CDC 7600 computer and used to calculate the effect on performance of deaerating the warm and cold water streams before entering the evaporator and condenser, respectively. This study indicates that there is no advantage to removing air from these streams compared with removing the air from the condenser.

  11. Thermal cycling in multifilamentary superconducting composites

    International Nuclear Information System (INIS)

    NbTi-Cu multifilamentary superconducting composites were embedded, polished, characterized by microscopic techniques, and analyzed in a qualitative and semiquantitative way by energy dispersion technique. The superconductors were submitted to thermal cycling between the ambient temperature and the boiling point of helium (4.2K), for different number of cycles. The aims were to study the correlation between the possible microstructural damages due to thermal stresses arising in the composite during cycling and the variation of properties of the material with the number of cycles as well as to verify the validity of an elastic model for thermal stresses for low temperature cycles. (author)

  12. 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.

  13. Understanding the petrochemical cycle: Part 1

    International Nuclear Information System (INIS)

    Fitness in the hydrocarbon processing industry (HPI) arena involves understanding and coping with business cycles: supply and demand. This becomes increasingly more important as the industry globalizes and matures. Competitive-edge thinking needs to look hard at the forces that influence business cycles. Recognition of potential pitfalls is very important when considering: future capacity expansion, mergers and acquisitions, market departure, plant closure, potential product substitution, etc. Understanding pricing mechanisms and the workings of hockey-stick profitability profiles help HPI operators endure cycle downturns and prepare plants to maximize profits for the next upswing. The paper discusses characteristic trends, cycles in the hydrocarbon processing industry, current conditions, and mitigating cycle effects

  14. Advanced Fuel Cycle Economic Sensitivity Analysis

    International Nuclear Information System (INIS)

    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

  15. 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

  16. Country nuclear fuel cycle profiles. Second ed

    International Nuclear Information System (INIS)

    This publication presents an overall review of worldwide nuclear fuel cycle activities, followed by country specific nuclear fuel cycle information. This information is presented in a concise form and focuses on the essential activities related to the nuclear fuel cycle in each country operating commercial nuclear power reactors or providing nuclear fuel cycle services. It also includes country specific diagrams which illustrate the main material flow in the nuclear fuel cycle. These illustrations are intended to help clarify understanding of both the essential nuclear fuel cycle activities in each country and international relationships. Section 1 provides an introduction and Section 2 a review of worldwide nuclear fuel cycle activities, dealing with mining and milling, conversion, enrichment, fuel fabrication, heavy water production, spent fuel management, and the dismantling of facilities. Individual country profiles are then given in Section 3

  17. 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.

  18. VISION: Verifiable Fuel Cycle Simulation Model

    Energy Technology Data Exchange (ETDEWEB)

    Jacob J. Jacobson; Abdellatif M. Yacout; Gretchen E. Matthern; Steven J. Piet; David E. Shropshire

    2009-04-01

    The nuclear fuel cycle is a very complex system that includes considerable dynamic complexity as well as detail complexity. In the nuclear power realm, there are experts and considerable research and development in nuclear fuel development, separations technology, reactor physics and waste management. What is lacking is an overall understanding of the entire nuclear fuel cycle and how the deployment of new fuel cycle technologies affects the overall performance of the fuel cycle. The Advanced Fuel Cycle Initiative’s systems analysis group is developing a dynamic simulation model, VISION, to capture the relationships, timing and delays in and among the fuel cycle components to help develop an understanding of how the overall fuel cycle works and can transition as technologies are changed. This paper is an overview of the philosophy and development strategy behind VISION. The paper includes some descriptions of the model and some examples of how to use VISION.

  19. 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 ...

  20. Conceptual design of an advanced absorption cycle: the double-effect regenerative absorption refrigeration cycle

    Energy Technology Data Exchange (ETDEWEB)

    Dao, K.

    1978-09-01

    An advanced absorption refrigeration cycle was proposed as a heat-activated refrigeration system. Referred to as the double-effect regenerative absorption cycle of cycle 2R, it improves the performance of the conventional single-effect absorption cycle at high heat source temperatures. The performance of cycle 2R continually improves as input temperatures rise, in contrast to the conventional double-effect absorption cycle that has a sharp cut-off temperature below which it ceases to operate. Cycle 2R operates with two subcycles, the first-effect and the second-effect subcycles.

  1. The heat engine cycle, the heat removal cycle, and ergonomics of the control room displays

    International Nuclear Information System (INIS)

    This paper discusses and illustrates the ergonomics of an integrated display, which will allow operators to monitor the heat engine cycle during normal operation of the plant, and the heat removal cycle during emergency operation of the plant. A computer-based iconic display is discussed as an overview to monitor these cycles. Specific emphasis is placed upon the process variables and process functions within each cycle, and the action of control systems and engineered safeguard systems within each cycle. This paper contains examples of display formats for the heat engine cycle and the heat removal cycle in a pressurized water reactor

  2. Fuel Cycle System Analysis Handbook

    International Nuclear Information System (INIS)

    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 uncertainty

  3. 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

  4. 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...

  5. 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

  6. 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...

  7. 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.

  8. 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.

  9. A Coupled Quantum Otto Cycle

    CERN Document Server

    Thomas, George

    2010-01-01

    We study the 1-d isotropic Heisenberg model of two spin-1/2 systems as a quantum heat engine. The engine undergoes a four-step Otto cycle where the two adiabatic branches involve changing the external magnetic field at a fixed value of the coupling constant. We find conditions for the engine efficiency to be higher than the uncoupled model; in particular, we find an upper bound which is tighter than the Carnot bound. A new domain of parameter values is pointed out which was not feasible in the interaction-free model. Locally, each spin seems to effect the flow of heat in a direction opposite to the global temperature gradient. This seeming contradiction to the second law can be resolved in terms of local effective temperature of the spins.

  10. Business cycles in oil economies

    International Nuclear Information System (INIS)

    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

  11. 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.)

  12. Carbon cycling in Lake Superior

    Science.gov (United States)

    Urban, N. R.; Auer, M. T.; Green, S. A.; Lu, X.; Apul, D. S.; Powell, K. D.; Bub, L.

    2005-06-01

    Carbon (C) cycling in Lake Superior was studied within the Keweenaw Interdisciplinary Transport Experiment in Superior (KITES) project to assess (1) whether the lake is net heterotrophic, (2) sources, sinks and residence time for dissolved organic carbon (DOC), (3) importance of terrigenous organic C subsidies, and (4) factors limiting C flow through bacteria. During 3 years of fieldwork, measurements were made of spatial and temporal distributions of C pools and rates of photosynthesis, community respiration, and bacterial production. Measurements were made of the composition of dissolved organic matter (DOM), rates of DOM photolysis, lability of DOM toward microbial consumption, and river inputs of DOM. All measurements suggest the lake is net heterotrophic. The C:N ratios of DOM suggest that it is primarily of terrigenous origin, but other characteristics (size distribution, UV absorption) point to the presence of autochthonous DOM and to alteration of terrigenous material. The lake mass balance indicates that the residence time (˜8 years) of the DOC pool (17 Tg) is short relative to the hydrologic residence time (170 years). The known flux of terrigenous DOC (˜1 Tg/yr) is too low to support annual bacterial carbon demand (6-38 Tg/yr), but microbial respiration is the major sink for terrigenous DOC. A rapidly cycling, autochthonous DOC pool must exist. Microbial activity was correlated with temperature, phosphorus availability, and DOC concentration but not with photosynthesis rates. Measurements of respiration (˜40 Tg/yr), photosynthesis (2-7 Tg/yr), and bacterial production (0.5-2 Tg/yr) are not all mutually compatible and result in a discrepancy in the organic carbon budget.

  13. 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

  14. 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.

  15. 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

  16. 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...

  17. 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

  18. 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

  19. 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...

  20. 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%.

  1. Automatic control of clock duty cycle

    Science.gov (United States)

    Feng, Xiaoxin (Inventor); Roper, Weston (Inventor); Seefeldt, James D. (Inventor)

    2010-01-01

    In general, this disclosure is directed to a duty cycle correction (DCC) circuit that adjusts a falling edge of a clock signal to achieve a desired duty cycle. In some examples, the DCC circuit may generate a pulse in response to a falling edge of an input clock signal, delay the pulse based on a control voltage, adjust the falling edge of the input clock signal based on the delayed pulse to produce an output clock signal, and adjust the control voltage based on the difference between a duty cycle of the output clock signal and a desired duty cycle. Since the DCC circuit adjusts the falling edge of the clock cycle to achieve a desired duty cycle, the DCC may be incorporated into existing PLL control loops that adjust the rising edge of a clock signal without interfering with the operation of such PLL control loops.

  2. 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.

  3. 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

  4. 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)

  5. Variants of closing the nuclear fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Andrianova, E. A., E-mail: Andrianova-EA@nrcki.ru; Davidenko, V. D.; Tsibulskiy, V. F.; Tsibulskiy, S. V. [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    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.

  6. LIFE CYCLE ANALYSIS CONSTRUCTION OF HIGHWAYS

    OpenAIRE

    ЛІСНІЧЕНКО, Т. В.; Національний авіаційний університет

    2016-01-01

    It proposed and studied the life cycle of the construction of public roads. We considere allphases of construction: from design to repiar. The scheme of the life cycle of the constructionof public roads is proposed. Construction of highway is seen as a project. The life cycle of theproject, known as a set of logically interrelated works in the completion of which achieved oneof the main results of the project. The complex of road construction works related to construction,reconstruction and r...

  7. 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

  8. 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....

  9. Workforce Planning over the Service Life Cycle

    OpenAIRE

    Ruwen Qin

    2011-01-01

    Services usually have a limited life under modern conditions of competition. The life cycle phenomenon is characterized by time-varying demand and a learning curve of workforce efficiency, making it difficult to determine staffing requirements. This paper initiates a study of the service life cycle phenomenon, from which the learning curve is found to be manageable through workforce planning. Therefore, optimal control is employed to model workforce planning over a service life cycle. An iter...

  10. Business Cycle and TPM of TNCs

    OpenAIRE

    Junrong Liu

    2011-01-01

    This article is devoted to analyses on effects of the four phases of business cycle on transfer pricing manipulation (TPM) of transnational corporations (TNCs) and TNCs’ possible TMP practices through business cycle. The researcher herein holds that business cycle arouses the fluctuation of economical indicators and policy changes, which subsequently affect TNCs’ production, financial situation, sales and their resource allocation globally. Acting as a reasoning business being, TNCs should ta...

  11. The economic implications of carbon cycle uncertainty

    OpenAIRE

    Smith, Steven J.; Edmonds, James A.

    2011-01-01

    This paper examines the implications of uncertainty in the carbon cycle for the cost of stabilizing carbon dioxideconcentrations. Using a state of the art integrated assessment model, we find that uncertainty in our understanding of thecarbon cycle has significant implications for the costs of a climate stabilization policy, with cost differences denominatedin trillions of dollars. Uncertainty in the carbon cycle is equivalent to a change in concentration target of up to 100 ppmv.The impact o...

  12. Austrian economics: application on Norwegian business cycles

    OpenAIRE

    Bjerkenes, Håkon; Kiil, Håkon; Anker-Nilssen, Paal

    2010-01-01

    This paper reviews the key elements of Austrian macroeconomics and aims to find out whether the Austrian business cycle theory can explain causes to Norwegian business cycles between 1979 and 2009. The Austrian school suggests that monetary interventions disturb the term structure of interest rates. This causes the capital structure to change which accounts for fluctuations of the business cycle. Credit- induced expansions with unchanged time-preferences create unsustaina...

  13. Liquid-Flooded Ericsson Power Cycle

    OpenAIRE

    James, Nelson A.; Braun, James E.; Groll, Eckhard A.; Horton, W. Travis

    2014-01-01

    In this paper, the use of liquid flooding is examined to create a high efficiency Ericsson Power Cycle. The introduction of significant amounts of liquid into the compression and expansion processes of a gas leads to quasi-isothermal behavior approximating that of an Ericsson cycle. A thermodynamic model is presented and various working fluid pairs are examined under operating conditions suitable for solar thermal power generation. The Liquid-Flooded Ericsson Cycle (LFEC) can be manufactured ...

  14. Business cycle forecasting and regime switching

    OpenAIRE

    Thórarinn G. Pétursson

    2000-01-01

    This paper applies Hamilton's (1989) Markov-switching model of business cycle dynamics to real GDP in Iceland for the period of 1945 to 1998. The resulting model gives a reasonable description of the data generating process for real GDP and produces business cycles that correspond quite well to conventional wisdom concerning the Icelandic business cycle. Although the model cannot be distinguished from a simple, linear time series model, it offers some improvements in terms of mean absolute fo...

  15. The vicious cycle of diabetes and pregnancy.

    Science.gov (United States)

    Pettitt, David J; Jovanovic, Lois

    2007-08-01

    The offspring of women with diabetes during pregnancy are at high risk of developing diabetes before they reach childbearing age, resulting in a vicious cycle of diabetes and pregnancy. New cases of diabetes enter the cycle as a result of the effects of the increasing obesity among our youth. Solutions need to be found to break this cycle by preventing diabetes or delaying its onset until later in life and by normalizing glucose regulation during pregnancy. PMID:17686406

  16. 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.

  17. 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...

  18. 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.

  19. Variants of closing the nuclear fuel cycle

    International Nuclear Information System (INIS)

    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

  20. Onsager coefficients of a Brownian Carnot cycle

    OpenAIRE

    Izumida, Yuki; Okuda, Koji

    2010-01-01

    We study a Brownian Carnot cycle introduced by T. Schmiedl and U. Seifert [Europhys. Lett. \\textbf{81}, 20003 (2008)] from a viewpoint of the linear irreversible thermodynamics. By considering the entropy production rate of this cycle, we can determine thermodynamic forces and fluxes of the cycle and calculate the Onsager coefficients for general protocols, that is, arbitrary schedules to change the potential confining the Brownian particle. We show that these Onsager coefficients contain the...

  1. Life cycle modelling for tourism areas

    OpenAIRE

    Alvares, Daniela; Lourenço, Júlia

    2005-01-01

    Modelling tourism development cycles associated with planning and investment cycles intends to be a contribution to the understanding of the tourism activity within a continuum process. It allows a better apprehension of the sequence of interdependencies that exist and can be addressed enlarging the well-known concept of tourism product and its life cycle. The proposed model can contribute for monitoring the tourism activity and improve its development in a sustainable way. If the tourist sit...

  2. Feasibility study on tandem fuel cycle

    International Nuclear Information System (INIS)

    The objective of this feasibility study is to review and assess the current state of technology concerning the tandem fuel cycle. Based on the results from this study, a long-term development plan suitable for Korea has been proposed for this cycle, i.e., the PWR → CANDU tandem fuel cycle which used plutonium and uranium, recovered from spent PWR fuel by co-processing, as fuel material for CANDU reactors. (Author)

  3. Governance and the corporate life-cycle

    OpenAIRE

    Thomas O'Connor; Julie Byrne

    2015-01-01

    Purpose –The purpose of this paper is to examine whether corporate governance changes along the corporate life-cycle. Design/methodology/approach -In a sample of 205 firms from 21 emerging market countries and using a life-cycle proxy from the dividends literature, the authors use a governance-prediction model which examines whether corporate governance differs along the corporate life-cycle. Findings -Mature firms tend to practice better overall corporate governance. Discipline and independe...

  4. Nonproliferation characteristics of advanced fuel cycle concepts

    International Nuclear Information System (INIS)

    The purpose of this study is to comment on the proliferation characteristic profiles of some of the proposed fuel cycle alternatives to help ensure that nonproliferation concerns are introduced into the early stages of a fuel cycle concept development program, and to perhaps aid in the more effective implementation of the international nonproliferation regime initiatives and safeguards methods and systems. Alternative cycle concepts proposed by several countries involve the recycle of spent fuel without the separation of plutonium from uranium and fission products

  5. Say's Law and the Business Cycles

    OpenAIRE

    Xianming Meng

    2006-01-01

    The relationship between Say's Law and the business cycle has been vigorously debated but no generally accepted agreement has yet been reached. Although this is a disputed topic, revisiting it anew could further develop economic theory, and enhance the further growth of the global economy. By scrutinising Say¡¯s Law, and its implicit business cycle theories, this paper claims that general gluts are possible, and that the essence of the business cycle is in innovation scarcity. Thus in order t...

  6. 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

  7. Rankine-cycle heating and cooling systems

    Science.gov (United States)

    1979-01-01

    Design for domestic or commercial solar heating and cooling system based on rankine heat pump cycle includes detailed drawings, performance data, equipment specifications, and other pertinent information.

  8. 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...

  9. One-cycle control of switching converters

    OpenAIRE

    Smedley, Keyue M.; Ćuk, Slobodan

    1995-01-01

    A new large-signal nonlinear control technique is proposed to control the duty-ratio d of a switch such that in each cycle the average value of a switched variable of the switching converter is exactly equal to or proportional to the control reference in the steady-state or in a transient. One-cycle control rejects power source perturbations in one switching cycle; the average value of the switched variable follows the dynamic reference in one switching cycle; and the controller corrects swit...

  10. 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.

  11. 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.

  12. Irreversible cycle in linear irreversible thermodynamics

    International Nuclear Information System (INIS)

    The reversible Carnot cycle in reversible thermodynamics is composed of two reversible heat exchange processes and two reversible adiabatic processes. We construct an irreversible cycle in linear irreversible thermodynamics by analogy with the reversible Carnot cycle. The irreversible cycle is composed of two linear irreversible heat exchange processes and two linear irreversible adiabatic processes. It is found that the Curzon-Alhborn efficiency can be attained if the power for each of the four linear irreversible processes reaches its maximum. The maximum efficiency is the Carnot efficiency. The strong coupling condition is prerequisite for the respective attainment of the Curzon-Alhborn efficiency and the Carnot efficiency.

  13. 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.

  14. Development Plan for the Fuel Cycle Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Brent Dixon

    2011-09-01

    The Fuel Cycle Simulator (FCS) project was initiated late in FY-10 as the activity to develop a next generation fuel cycle dynamic analysis tool for achieving the Systems Analysis Campaign 'Grand Challenge.' This challenge, as documented in the Campaign Implementation Plan, is to: 'Develop a fuel cycle simulator as part of a suite of tools to support decision-making, communication, and education, that synthesizes and visually explains the multiple attributes of potential fuel cycles.'

  15. 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.

  16. 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, ...

  17. Back Work Ratio of Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Malaver de la Fuente M.

    2010-07-01

    Full Text Available This paper analizes the existing relation between temperatures, back work ratio and net work of Brayton cycle, a cycle that describes gas turbine engines performance. The application of computational soft ware helps to show the influence of back work ratio or coupling ratio, compressor and turbine in let temperatures in an ideal thermodynamical cycle. The results lead to deduce that the maximum value reached in back work ratio will depend on the ranges of maximum and minimal temperatures of Brayton cycle.

  18. Closing the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Generally the case for closing the nuclear fuel cycle is based on the strategic value of the uranium and plutonium recovered by reprocessing spent fuel. The energy content of 1 t of spent fuel varies from 10,000 to 40,000 t of coal equivalent depending on the reactor type from which the spent fuel arises. Recycling in fast reactors would increase these values by a factor or roughly 40. Reprocessing in the UK has its roots in the technology developed during and after the 1939-45 war to provide plutonium for defence purposes. At BNFL's Sellafield site in northern England the commercial reprocessing of spent fuel has been undertaken for over 30 years with a cumulative throughput of over 30,000 tU. Over 15,000 tU of the uranium recovered has been recycled and some 70% of all the UK's AGR fuel has been produced from this material. As a consequence the UK's bill for imported uranium has been reduced by several hundred million pounds sterling. This report discusses issues associated with reprocessing, uranium, and plutonium recycle

  19. 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

  20. Kozai Cycles and Tidal Friction

    Energy Technology Data Exchange (ETDEWEB)

    L, K; P.P., E

    2009-07-17

    Several studies in the last three years indicate that close binaries, i.e. those with periods of {approx}< 3 d, are very commonly found to have a third body in attendance. We argue that this proves that the third body is necessary in order to make the inner period so short, and further argue that the only reasonable explanation is that the third body causes shrinkage of the inner period, from perhaps a week or more to the current short period, by means of the combination of Kozai cycles and tidal friction (KCTF). In addition, once KCTF has produced a rather close binary, magnetic braking also combined with tidal friction (MBTF) can decrease the inner orbit further, to the formation of a contact binary or even a merged single star. Some of the products of KCTF that have been suggested, either by others or by us, are W UMa binaries, Blue Stragglers, X-ray active BY Dra stars, and short-period Algols. We also argue that some components of wide binaries are actually merged remnants of former close inner pairs. This may include such objects as rapidly rotating dwarfs (AB Dor, BO Mic) and some (but not all) Be stars.