WorldWideScience

Sample records for speculative position limits

  1. Positive Feedback Investment Strategies and Destabilizing Rational Speculation

    OpenAIRE

    J. Bradford De Long; Andrei Shleifer; Lawrence H. Summers; Robert J. Waldmann

    1989-01-01

    Analyses of the role of rational speculators in financial markets usually presume that such investors dampen price fluctuations by trading against liquidity or noise traders. This conclusion does not necessarily hold when noise traders follow positive-feedback investment strategies buy when prices rise and sell when prices fall. In such cases, it may pay rational speculators to try to jump on the bandwagon early and to purchase ahead of noise trader demand. If rational speculators' attempts t...

  2. 17 CFR 150.5 - Exchange-set speculative position limits.

    Science.gov (United States)

    2010-04-01

    ..., straddles, or arbitrage,” of from fixing limits which apply to such positions which are different from... opportunity for arbitrage between the futures market and the cash market in the commodity underlying the... pursuant to this section shall apply to bona fide hedging positions as defined by a contract market in...

  3. 78 FR 75679 - Position Limits for Derivatives

    Science.gov (United States)

    2013-12-12

    ... practices for compliance with Designated Contract Market (``DCM'') core principle 5 and Swap Execution Facility (``SEF'') core principle 6 in respect of exchange- set speculative position limits and position... To Become Guidance on and Acceptable Practices for Compliance with DCM Core Principle 5 3. The CFTC...

  4. 75 FR 50950 - Federal Speculative Position Limits for Referenced Energy Contracts and Associated Regulations

    Science.gov (United States)

    2010-08-18

    ..., section 4a(a) of the Act authorized the Commission to establish position limits for contracts traded on or... Position Limits for Referenced Energy Contracts and Associated Regulations AGENCY: Commodity Futures... and option contracts based on a limited set of exempt commodities,\\1\\ namely certain energy...

  5. Rational destabilizing speculation, positive feedback trading, and the oil bubble of 2008

    International Nuclear Information System (INIS)

    Tokic, Damir

    2011-01-01

    This article examines how the interaction of different participants in the crude oil futures markets affects the crude oil price efficiency. Normally, the commercial market participants, such as oil producers and oil consumers, act as arbitrageurs and ensure that the price of crude oil remains within the fundamental value range. However, institutional investors that invest in crude oil to diversify their portfolios and/or hedge inflation can destabilize the interaction among commercial participants and liquidity-providing speculators. We argue that institutional investors can impose limits to arbitrage, particularly during the financial crisis when the investment demand for commodities is particularly strong. In support, we show that commercials hedgers had significantly reduced their short positions leading to the 2008 oil bubble-they were potentially aggressively offsetting their short hedges. As a result, by essentially engaging in a positive feedback trading, commercial hedgers at least contributed to 'the 2008 oil bubble'. These findings have been mainly overlooked by the existing research. - Research Highlights: → This article finds that commercial hedgers at least contributed to the 2008 oil bubble. → Commercial hedgers were aggressively offsetting their short hedges leading to the oil bubble peak. → Commercial hedgers, thus, unwillingly engaged in positive feedback trading. → Institutional investors potentially destabilized the oil markets in 2008.

  6. Rational destabilizing speculation, positive feedback trading, and the oil bubble of 2008

    Energy Technology Data Exchange (ETDEWEB)

    Tokic, Damir, E-mail: Damir.tokic@esc-rennes.f [ESC Rennes - International School of Business, 2 Rue Robert d' Arbissel, 35065 Rennes cedex (France)

    2011-04-15

    This article examines how the interaction of different participants in the crude oil futures markets affects the crude oil price efficiency. Normally, the commercial market participants, such as oil producers and oil consumers, act as arbitrageurs and ensure that the price of crude oil remains within the fundamental value range. However, institutional investors that invest in crude oil to diversify their portfolios and/or hedge inflation can destabilize the interaction among commercial participants and liquidity-providing speculators. We argue that institutional investors can impose limits to arbitrage, particularly during the financial crisis when the investment demand for commodities is particularly strong. In support, we show that commercials hedgers had significantly reduced their short positions leading to the 2008 oil bubble-they were potentially aggressively offsetting their short hedges. As a result, by essentially engaging in a positive feedback trading, commercial hedgers at least contributed to 'the 2008 oil bubble'. These findings have been mainly overlooked by the existing research. - Research Highlights: {yields} This article finds that commercial hedgers at least contributed to the 2008 oil bubble. {yields} Commercial hedgers were aggressively offsetting their short hedges leading to the oil bubble peak. {yields} Commercial hedgers, thus, unwillingly engaged in positive feedback trading. {yields} Institutional investors potentially destabilized the oil markets in 2008.

  7. A new approach to measure speculation in the oil futures market and some policy implications

    International Nuclear Information System (INIS)

    Chan, Leo H.; Nguyen, Chi M.; Chan, Kam C.

    2015-01-01

    We propose using a new relative measure, the speculative ratio, defined as trading volume divided by open interest, to gauge speculative activity in the oil futures market. We apply the speculative ratio to examine the relation between basis and speculative activity in the oil futures market before and after the financialization of the oil market in 2003. Our finding suggests that the oil futures market is dominated by uninformed speculators in the post-financialization period. Our finding carries several practical policy implications, as follows: (1) both the commodity exchange and the regulator should design regulations and trading policies that improve basis risk; (2) on the commodity exchange side, new policies on margin requirements and position limits for speculators should be implemented; (3) margin requirements should be based on the level of basis risk; (4) regulators should speed up implementation of the position limit rule in the Dodd–Frank Act; and (5) stronger and more meaningful enforcement actions by regulators are required to punish and deter market manipulators. - Highlights: • Use a new speculative ratio to gauge speculative activities in oil futures market. • Examine the relation between basis and speculative activities. • The new speculative ratio also works well in the post-2008 oil bubble period. • Oil futures market is dominated by uninformed speculators in post-financialization in 2003.

  8. Foreign Exchange Speculation: An Event Study

    Directory of Open Access Journals (Sweden)

    Rob Hayward

    2018-02-01

    Full Text Available Does speculation facilitate price discovery or instability? If it is price discovery, it is beneficial and should be encouraged; if it is instability, welfare is enhanced by its reduction. This paper seeks to distinguish between these two characteristics by analysing those times when speculation in the foreign exchange market is most extreme. A series of event studies are conducted on the extremes of speculative sentiment and speculative activity. If speculation is noise, extreme sentiment and extreme positions should lead to overshooting and increase risk of subsequent reversals. The finding that speculative extremes do not provide information about subsequent returns implies that speculation is part of the process of price discovery and that efforts to reduce it would reduce the informational efficiency of financial markets.

  9. FCJ-142 Spectacles and Tropes: Speculative Design and Contemporary Food Cultures

    Directory of Open Access Journals (Sweden)

    Carl DiSalvo

    2012-07-01

    Full Text Available Speculative design is a particularly inventive mode of design that is concerned with developing imaginative futures or alternate presents. Often, the purpose of speculative design is to prompt reflection on contemporary conditions and express possible implications of current trends in science and technology. Like all design, speculative design reproduces as well as invents culture and there are limits to the work it does. In this essay, I trace the ways speculative design reproduces contemporary food cultures through two projects: Guide to Free Farming (2009 and Family Whiskey (2010. From these projects I draw out and discuss two strategies of speculative design: the use of spectacle and the use of tropes. I describe how these strategies work to attract us to images and objects, and I identify their limits in providing content, meaning, and significance. In concluding, I consider how speculative design might enable more substantive engagement with issues.

  10. Currency Speculation in Danish Non-Financial Firms: Cowboys or Suits?

    DEFF Research Database (Denmark)

    Aabo, Tom

    Gambling has attracted people since ancient times. This empirical paper surveys and investigates the nature of corporate speculation done by Danish non-financial companies on the currency markets. The empirical results show that such speculation is widespread and that the extent of speculation...... is positively linked to the size of the company, to the degree of foreign involvement, and to the conservatism of the capital structure. The empirical results also show that if a person (often the founder or his relatives) is the largest shareholder in the company, the extent of speculation is reduced....... The results are import in understanding the gap between a widespread corporate practice of speculation and a theoretical and empirical literature that leaves little support for such speculation....

  11. Exchange Rate Exposure Management: "Speculation" in Non-Financial Companies

    DEFF Research Database (Denmark)

    Aabo, Tom

    "Speculation" in non-financial companies in relation to exchange rate exposure management constitutes one of the contributing factors behind corporate (or more widespread) crises. Deviations from benchmark positions constitute speculation. An empirical study of Danish non-financial companies finds...... that the larger the company (ability) and the larger its relative sale on foreign markets (relevance), the more likely the company will be to benchmark its exchange rate exposures. However, at the same time the very same factors (size and foreign sale) lead to more extensive speculation. Financial solvency (value...

  12. Crude oil prices: Speculation versus fundamentals

    Science.gov (United States)

    Kolodziej, Marek Krzysztof

    Beginning in 2004, the price of crude oil fluctuates rapidly over a wide range. Large and rapid price increases have recessionary consequences and dampen long-term infrastructural investment. I investigate whether price changes are driven by market fundamentals or speculation. With regard to market fundamentals, I revisit econometric evidence for the importance of demand shocks, as proxied by dry maritime cargo rates, on oil prices. When I eliminate transportation costs from both sides of the equation, disaggregate OPEC and non-OPEC production, and allow for more than one cointegrating relation, I find that previous specifications are inconsistent with arguments that demand shocks play an important role. Instead, results confirm the importance of OPEC supply shocks. I investigate two channels by which speculation may affect oil prices; the direct effect of trader behavior and changes in oil from a commodity to a financial asset. With regard to trader behavior, I find evidence that trader positions are required to explain the spread between spot and futures prices of crude oil on the New York Mercantile Exchange. The inclusion of trader positions clarifies the process of equilibrium error correction, such that there is bidirectional causality between prices and trader positions. This creates the possibility of speculative bubbles. With regard to oil as a commodity and/or financial asset, I use a Kalman Filter model to estimate the time-varying partial correlation between returns to investments in equity and oil markets. This correlation changes from negative to positive at the onset of the 2008 financial crisis. The low interest rates used to rescue the economy depress convenience yields, which reduces the benefits of holding oil as a commodity. Instead, oil becomes a financial asset (on net) as the oil market changed from contango to backwardation. Contradicting simple political narratives, my research suggests that both market fundamentals and speculation drive

  13. Corporate foreign exchange speculation and integrated risk management

    DEFF Research Database (Denmark)

    Aabo, Tom; Hansen, Marianna Andryeyeva; Pantzalis, Christos

    2012-01-01

    Purpose – The purpose of this paper is to investigate how non-finance departmental involvement in the management of exchange rate risks impacts the extent of foreign exchange speculation in non-financial firms. Design/methodology/approach – We survey non-financial firms in a small open economy...... (Denmark) to investigate the extent of foreign exchange speculation and how it is related to the degree of non-finance departmental involvement in the management of exchange rate risks. We employ binary and ordered probit regression analysis. Findings – We find a positive link between 1) the extent...... to which other departments than the finance department is involved in the management of exchange rate risks and 2) the extent to which the firm is likely to speculate – whether in the form of selective hedging or active speculation – on the foreign exchange market. Practical implications – Our findings...

  14. Derivative markets, speculation and oil prices

    International Nuclear Information System (INIS)

    Babusiaux, D.; Lasserre, F.; Pierru, A.

    2010-01-01

    Recent movements in oil prices have been ascribed by a number of analysts and political leaders not to market fundamentals but to the speculative positions taken by financial investors in derivatives markets. Various economists including Nobel Prize Paul Krugman believe however that the constitution of stocks is a necessary element for speculation, a feature that was not very evident during the sudden price increase in 2008; but these points of view are not entirely incompatible. Various explanations can be put forward, among which the most important is demand inertia. On the very short run, demand price elasticity is significantly lower than that usually calculated for the short term, which can significantly reduce the impact - on stocks - of a temporary price increase provoked by financial investors' behavior. (authors)

  15. Freud's metapsychological speculations.

    Science.gov (United States)

    Fulgencio, Leopoldo

    2005-02-01

    In this paper, the author seeks to analyse the nature and function of metapsychological theory in Freudian psychoanalysis. He shows that Freudian psychoanalytic theory is composed of an empirical part--the psychology of clinical facts--and a speculative part--metapsychology. Freud considers this latter part as being a speculative superstructure of value that is only heuristic, capable of being supplanted by other superstructures of the same type. The author sustains the idea that this metapsychology is the fruit of speculative method, whose foundations were elaborated by philosophers and epistemologists before Freud, including Immanuel Kant and Ernst Mach. He concludes with considerations regarding the future of metapsychological theorisation, presenting criticisms of Freudian metapsychology offered by both philosophers and psychoanalysts, and pointing to the perspective opened by Donald W. Winnicott of a psychoanalysis without metapsychology.

  16. Speculation and Fiction: Introduction

    Directory of Open Access Journals (Sweden)

    Sourit Bhattacharya

    2015-07-01

    Full Text Available As students of literature, one of the most frequent questions we encounter is: how does one write anything? What are the factors responsible for writing fiction? Does fiction have its autonomous qualities? Put in a slightly different way: what is thought or how is thought put into fiction? Broadly speaking, the study into the domain of thought is speculation. The Oxford English dictionary defines “speculation” this way: “the forming of a theory or conjecture without firm evidence.”1 Speculation then is a field of thinking thought, conjecture, or hypothesis which seeks for evidence to become “fact” or “practice.” In such argument, the foundational aspect of all philosophy appears to be speculation. This won’t be an overstatement if we endeavour to trace the genealogy and use of the term in ancient Indian philosophy to the Greco-Roman world, or in the mediaeval scholastic philosophy in Europe.2 From the term’s rooted traditional philosophical basis to a particular meaning-making in genre fiction, there have been many developments but one aspect has been relatively unchanged: the question of conjecture. Speculative fiction does not have a rigid definition and is putatively understood to be an amalgam of many genres, forms, thoughts, or techniques. It is also about a world which is not necessarily the existent but in most cases the “material-possible”: the conjectural. Fiction in that analysis appears to be the medium through which the conjectural element of speculation is given a concrete material body. But fiction is not an end product only, the printed book or the text in this case, but also a world of ideas, thoughts, and imagination. In that sense, there is fiction already always within the “genre” of speculation. These are some of the interrelated but not always easily articulable aspects that we wanted to engage with in this volume, “Speculation and Fiction.”

  17. 75 FR 4143 - Federal Speculative Position Limits for Referenced Energy Contracts and Associated Regulations

    Science.gov (United States)

    2010-01-26

    ... merchandises or anticipates owning, producing, manufacturing, processing, or merchandising, (ii) The potential... merchandising of the cash position which is being offset.'' 17 CFR 1.3(z). \\50\\ 17 CFR 1.47(b)(2). In addition...

  18. Implicit, explicit and speculative knowledge

    NARCIS (Netherlands)

    van Ditmarsch, H.; French, T.; Velázquez-Quesada, F.R.; Wáng, Y.N.

    We compare different epistemic notions in the presence of awareness of propositional variables: the logic of implicit knowledge (in which explicit knowledge is definable), the logic of explicit knowledge, and the logic of speculative knowledge. Speculative knowledge is a novel epistemic notion that

  19. Red Shifts and Existing Speculations

    Science.gov (United States)

    Aisenberg, Sol

    2009-03-01

    There are many current flaws, mysteries, and errors in the standard model of the universe - all based upon speculative interpretation of many excellent and verified observations. The most serious cause of some errors is the speculation about the meaning of the redshifts observed in the 1930s by Hubble. He ascribed the redshifts as due to ``an apparent Doppler effect''. This led to speculation that the remote stars were receding, and the universe was expanding -- although without observational proof of the actual receding velocity of the stars. The age of the universe, based upon the Hubble constant is pure speculation because of lack of velocity demonstration. The belief in expansion, the big bang, and of inflation should be reexamined. Also, the redshift cannot always be used as a distance measure, particularly for photons from quasars containing massive black holes that can reduce photon energy through gravitational attraction. If the linear Hubble constant is extrapolated to the most remote super novae and beyond, it would eventually require that the corresponding photon energy go to zero or become negative -- according to Hubble linear relationship. This should require a reexamination of the meaning of the red shift and the speculative consequences and give a model with fewer mysteries.

  20. Jordan Krall's speculative fiction

    DEFF Research Database (Denmark)

    Doubinsky, Sebastien

    2017-01-01

    Jordan Krall is one of the most interesting writers in American speculative fiction. This article studies the way Krall redefines the tropes and frames of classical dystopian fiction and references, turning them into an idiosyncratic construction.......Jordan Krall is one of the most interesting writers in American speculative fiction. This article studies the way Krall redefines the tropes and frames of classical dystopian fiction and references, turning them into an idiosyncratic construction....

  1. I/O Speculation for the Microsecond Era

    DEFF Research Database (Denmark)

    Wei, Michael Yung Chung; Bjørling, Matias; Bonnet, Philippe

    2014-01-01

    are suboptimal for microsecond devices - they either block the processor for tens of microseconds or yield the processor only to be ready again microseconds later. Speculation is an alternative technique that resolves the issues of yielding and blocking by enabling an application to continue running until...... the application produces an externally visible side effect. State-of-the-art techniques for speculating on I/O requests involve checkpointing, which can take up to a millisecond, squandering any of the performance bene-fits microsecond scale devices have t o offer. In this paper, we survey how speculation can...... address the challenges that microsecond scale devices will bring. We measure applications for the potential benefit to be gained from speculation and examine several classes of speculation techniques. In addition, we propose two new techniques, hardware checkpoint and checkpoint-free speculation. Our...

  2. Video Game Effects--Confirmed, Suspected, and Speculative: A Review of the Evidence

    Science.gov (United States)

    Barlett, Christopher P.; Anderson, Craig A.; Swing, Edward L.

    2009-01-01

    This literature review focuses on the confirmed, suspected, and speculative effects of violent and non-violent video game exposure on negative and positive outcomes. Negative outcomes include aggressive feelings, aggressive thoughts, aggressive behavior, physiological arousal, and desensitization, whereas positive outcomes include various types of…

  3. Relaxing Competition through Speculation : Committing to a Negative Supply Slope

    NARCIS (Netherlands)

    Holmberg, P.; Willems, Bert

    2012-01-01

    Abstract: We demonstrate how suppliers can take strategic speculative positions in derivatives markets to soften competition in the spot market. In our game, suppliers first choose a portfolio of call options and then compete with supply functions. In equilibrium firms sell forward contracts and buy

  4. Relaxing competition through speculation : Committing to a negative supply slope

    NARCIS (Netherlands)

    Holmberg, Par; Willems, Bert

    We demonstrate how commodity producers can take strategic speculative positions in derivatives markets to soften competition in the spot market. In our game, producers first choose a portfolio of call options and then compete in supply functions. In equilibrium, producers sell forward contracts and

  5. Visionary medicine: speculative fiction, racial justice and Octavia Butler's 'Bloodchild'.

    Science.gov (United States)

    Pasco, John Carlo; Anderson, Camille; DasGupta, Sayantani

    2016-12-01

    Medical students across the USA have increasingly made the medical institution a place for speculating racially just futures. From die-ins in Fall 2014 to silent protests in response to racially motivated police brutality, medical schools have responded to the public health crisis that is racial injustice in the USA. Reading science fiction may benefit healthcare practitioners who are already invested in imagining a more just, healthier futurity. Fiction that rewrites the future in ways that undermine contemporary power regimes has been termed 'visionary fiction'. In this paper, the authors introduce 'visionary medicine' as a tool for teaching medical students to imagine and produce futures that preserve health and racial justice for all. This essay establishes the connections between racial justice, medicine and speculative fiction by examining medicine's racially unjust past practices, and the intersections of racial justice and traditional science and speculative fiction. It then examines speculative fiction author Octavia Butler's short story 'Bloodchild' as a text that can introduce students of the medical humanities to a liberatory imagining of health and embodiment, one that does not reify and reinscribe boundaries of difference, but reimagines the nature of Self and Other, power and collaboration, agency and justice. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  6. 10 CFR 434.520 - Speculative buildings.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Speculative buildings. 434.520 Section 434.520 Energy... RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.520 Speculative buildings. 520... for the lighting power provided for the common areas of the building. 520.4Documentation for future...

  7. The Speculative Nature of Stock Market

    Directory of Open Access Journals (Sweden)

    Bogdan-Gabriel FILIPESCU

    2011-12-01

    Full Text Available This paper focuses on the speculative nature of the stock market in Romania, emphasizing the basic rules and risks associated with stock transactions. On the one hand, the speculative nature may be considered as a mandatory feature of the stock market, for the purposes of supporting a fair and efficient functioning stock system. On the other hand, the term "speculative" can be also interpreted in a negative direction, i.e. in combination with market manipulation or market abuse. Related to this latter interpretation, the study refers to European legislation on market abuse, accepted market practices and those that constitute market manipulation.

  8. The timeless aspect of nuclear speculation

    International Nuclear Information System (INIS)

    Kurucz, J.

    1980-01-01

    The author understands peaceful utilization of nuclear energy as a wave of speculations and explains it by the spirit of capitalism. In the fifties the American initiative had resulted in a peaceful utilization of nuclear energy and led to the development which the author terms nuclear speculation and compares with a classic speculation, namely the Panama affair. The main conflict of present days - the conflict of the nuclear club and its opponents - were not yet over. The one would lose who had less persistence. In the supplement the author gives sociological comments on breeding reactor technology and basic law with regard to the decrees of the court of Kalkar. (HSCH) [de

  9. The importance of speculative uranium deposits

    International Nuclear Information System (INIS)

    Kaiser, H.; Roth-Seefrid, H.

    1980-01-01

    Since current known uranium deposits (5 million t U) will either have been exhausted by the end of the century, or must be held in reserve for the thermal converter reactors which will be in operation by that time, the development of nuclear energy after the year 2000 will depend to a large extent on the early availability of speculative uranium deposits. The speculative deposits represent, by definition, the quantities of uranium which are presumed to exist in addition to the 'known' deposits and which can ultimately be exploited according to current technical-economic and ecological standpoints. When viewed critically, however, the US-DOE model used for this purpose projects an over-optimistic picture of uranium supplies and was, therefore, only accepted by the INFCE with a series of limitations and reservations. Overall the model represents a well-founded reassurance for future uranium exploration - nothing more and nothing less. The model clearly shows that due to the long lead-in times considerable expenditure will be required for uranium exploration in the coming years. It is probable that this level of investment will have to be increased several times over in the 1990s as the search moves to greater depths and to less-accessible regions. (orig./UA) [de

  10. Speculative and hedging activities in the European carbon market

    International Nuclear Information System (INIS)

    Lucia, Julio J.; Mansanet-Bataller, Maria; Pardo, Ángel

    2015-01-01

    We explore the dynamics of the speculative and hedging activities in European futures carbon markets by using volume and open interest data. A comparison of the three phases in the European Union Emission Trading Scheme (EU ETS) reveals that (i) Phase II of the EU ETS seems to be the most speculative phase to date and (ii) the highest degree of speculative activity for every single phase occurs at the moment of listing the contracts for the first time. A seasonality analysis identifies a higher level of speculation in the first quarter of each year, related to the schedule of deadlines of the EU ETS. In addition, a time series analysis confirms that most of the speculative activity each year occurs in the front contract, whereas the hedging demand concentrates in the second-to-deliver futures contract. -- Highlights: •This study explores the evolution of speculative and hedging activities in futures carbon markets by using volume and open interest data. •Phase II of the EU ETS seems to be the most speculative phase to date. •A seasonality analysis identifies a higher level of speculation in the first quarter of each year. •Most of the speculative activity occurs in the front contract. •The hedging demand concentrates in the second-to-deliver futures contract

  11. The conceptual and empirical relationship between gambling, investing, and speculation.

    Science.gov (United States)

    Arthur, Jennifer N; Williams, Robert J; Delfabbro, Paul H

    2016-12-01

    Background and aims To review the conceptual and empirical relationship between gambling, investing, and speculation. Methods An analysis of the attributes differentiating these constructs as well as identification of all articles speaking to their empirical relationship. Results Gambling differs from investment on many different attributes and should be seen as conceptually distinct. On the other hand, speculation is conceptually intermediate between gambling and investment, with a few of its attributes being investment-like, some of its attributes being gambling-like, and several of its attributes being neither clearly gambling or investment-like. Empirically, gamblers, investors, and speculators have similar cognitive, motivational, and personality attributes, with this relationship being particularly strong for gambling and speculation. Population levels of gambling activity also tend to be correlated with population level of financial speculation. At an individual level, speculation has a particularly strong empirical relationship to gambling, as speculators appear to be heavily involved in traditional forms of gambling and problematic speculation is strongly correlated with problematic gambling. Discussion and conclusions Investment is distinct from gambling, but speculation and gambling have conceptual overlap and a strong empirical relationship. It is recommended that financial speculation be routinely included when assessing gambling involvement, and there needs to be greater recognition and study of financial speculation as both a contributor to problem gambling as well as an additional form of behavioral addiction in its own right.

  12. ZGS highlights and speculations

    International Nuclear Information System (INIS)

    Fields, T.H.

    1979-01-01

    Several examples of unfinished business of the ZGS program are described. These examples cover physics, apparatus, and institutional subjects. Speculations are given about the evolution of these subjects during the 1980's

  13. A Nonlinear Super-Exponential Rational Model of Speculative Financial Bubbles

    Science.gov (United States)

    Sornette, D.; Andersen, J. V.

    Keeping a basic tenet of economic theory, rational expectations, we model the nonlinear positive feedback between agents in the stock market as an interplay between nonlinearity and multiplicative noise. The derived hyperbolic stochastic finite-time singularity formula transforms a Gaussian white noise into a rich time series possessing all the stylized facts of empirical prices, as well as accelerated speculative bubbles preceding crashes. We use the formula to invert the two years of price history prior to the recent crash on the Nasdaq (April 2000) and prior to the crash in the Hong Kong market associated with the Asian crisis in early 1994. These complex price dynamics are captured using only one exponent controlling the explosion, the variance and mean of the underlying random walk. This offers a new and powerful detection tool of speculative bubbles and herding behavior.

  14. Speculative Betas

    OpenAIRE

    Harrison Hong; David Sraer

    2012-01-01

    We provide a model for why high beta assets are more prone to speculative overpricing than low beta ones. When investors disagree about the common factor of cash-flows, high beta assets are more sensitive to this macro-disagreement and experience a greater divergence-of-opinion about their payoffs. Short-sales constraints for some investors such as retail mutual funds result in high beta assets being over-priced. When aggregate disagreement is low, expected return increases with beta due to r...

  15. Why Meillassoux’s Speculative Materialism Struggles with Ancestrality

    Directory of Open Access Journals (Sweden)

    Ciprian Jeler

    2014-12-01

    Full Text Available This paper shows that Quentin Meillassoux’s speculative materialism doesn’t offer us the means to account for the ancestral statements that the modern sciences produce, i.e. for the scientific statements about events preceding all forms of life. An analysis of the reasons why Meillassoux thinks that the problem of ancestrality problematizes the contemporary self-evidence of correlationism is first offered. The results of this analysis are then applied to speculative materialism itself and the consequences are not very promising: very much like correlationism, speculative materialism explicitly denies what I call the “generalized version of the realistic assumption of science” and, in so doing, renders scientific ancestral statements de jure unverifiable. Therefore, if correlationism is rendered suspicious by the issue of ancestrality, the same can be said of speculative materialism.

  16. Taxing fossil fuels under speculative storage

    International Nuclear Information System (INIS)

    Tumen, Semih; Unalmis, Deren; Unalmis, Ibrahim; Unsal, D. Filiz

    2016-01-01

    Long-term environmental consequences of taxing fossil fuel usage have been extensively studied in the literature. However, these taxes may also impose several short-run macroeconomic policy challenges, the nature of which remains underexplored. This paper investigates the mechanisms through which environmental taxes on fossil fuel usage can affect the main macroeconomic variables in the short-run. We concentrate on a particular mechanism: speculative storage. Formulating and using a dynamic stochastic general equilibrium (DSGE) model, calibrated for the United States, with an explicit storage facility and nominal rigidities, we show that in designing environmental tax policies it is crucial to account for the fact that fossil fuel prices are subject to speculation. The existence of forward-looking speculators in the model improves the effectiveness of tax policies in reducing fossil fuel usage. Improved policy effectiveness, however, is costly: it drives inflation and interest rates up, while impeding output. Based on this tradeoff, we seek an answer to the question how monetary policy should interact with environmental tax policies in our DSGE model of fossil fuel storage. We show that, in an environment with no speculative storers, monetary policy should respond to output along with CPI inflation in order to minimize the welfare losses brought by taxes. However, when the storage facility is activated, responding to output in the monetary policy rule becomes less desirable.

  17. Speculation and the 2008 oil bubble: The DCOT Report analysis

    International Nuclear Information System (INIS)

    Tokic, Damir

    2012-01-01

    This article analyzes the CFTC's Disaggregated Commitments of Traders (DCOT) Report to get more insights into the behavior of different traders during the 2008 oil bubble. The analysis shows that: (1) the Money Manager category perfectly played the oil bubble, got in early and started selling shortly before the bubble peak; (2) the Producer/Merchant/Processor/User category and the Nonreportable category were covering their short positions into the peak of the bubble; (3) the Swap/Dealer category benefited while the price of oil was rising, but incurred heavy losses as the price of oil collapsed; (4) we find no indications of speculation by any group of traders via the positive feedback trading or rational destabilization; and (5) we do, however, criticize the commercial hedgers for failing to arbitrage the soaring oil prices in 2008. - Highlights: ► We analyze the DCOT Report to study the behavior of traders during the 2008 oil bubble. ► the Money Manger category perfectly played the oil bubble. ► the Producer/Merchant/Processor/User and the Nonreportables engaged in short covering. ► the Swap/Dealer incurred heavy losses as the price of oil collapsed. ► We find no indications of speculation by any category.

  18. Version pressure feedback mechanisms for speculative versioning caches

    Science.gov (United States)

    Eichenberger, Alexandre E.; Gara, Alan; O& #x27; Brien, Kathryn M.; Ohmacht, Martin; Zhuang, Xiaotong

    2013-03-12

    Mechanisms are provided for controlling version pressure on a speculative versioning cache. Raw version pressure data is collected based on one or more threads accessing cache lines of the speculative versioning cache. One or more statistical measures of version pressure are generated based on the collected raw version pressure data. A determination is made as to whether one or more modifications to an operation of a data processing system are to be performed based on the one or more statistical measures of version pressure, the one or more modifications affecting version pressure exerted on the speculative versioning cache. An operation of the data processing system is modified based on the one or more determined modifications, in response to a determination that one or more modifications to the operation of the data processing system are to be performed, to affect the version pressure exerted on the speculative versioning cache.

  19. Speculative Before the Turn: Reintroducing Feminist Materialist Performativity

    Directory of Open Access Journals (Sweden)

    Cecilia Åsberg

    2015-11-01

    Full Text Available This is a moment for new conversations and new synergies. While a wealth of contemporary speculative materialisms is currently circulating in academia, art and activism, in this article we focus upon a few ethico-political stakes in the different, loosely affiliated conceptions of ontologies of immanence. More specifically, we are concerned here with the very meaning of speculation itself after the many new headings of immanent ontologies, such as object-oriented ontology (OOO, speculative realism or the (feminist new materialisms. Our concern is a feminist concern, as some of the immanent ontologies seem to actively connect with the varied feminist archive of speculative thought while others seem to actively disconnect from the very same archive. What does this imply for the feminist scholar who is in want of tools for navigating the contemporary landscape of ontologies of immanence? Here, we highlight some important overlapping as well as poignant clashes between various feminist materialist genealogies and OOO/speculative realism. In our discussion we underline the importance of situatedness and context, relationality and affinity—and the possibility for rewiring relations—amid a plethora of lively historiographies and emergent post-disciplinary movements and world-makings.

  20. Defending against speculative attacks

    NARCIS (Netherlands)

    Daniëls, T.; Jager, H.; Klaassen, F.

    2009-01-01

    While virtually all currency crisismodels recognise that the fate of a currency peg depends on how tenaciously policy makers defend it, they seldom model how this is done. We incorporate themechanics of speculation and the interest rate defence against it in the model of Morris and Shin (American

  1. Carry trade as a speculative investment strategy in Serbia

    Directory of Open Access Journals (Sweden)

    Bungin Sanja

    2012-12-01

    Full Text Available This paper is analyses causes and the consequences of a speculative investment carry trade strategy in the exchange market in Serbia. The presence of such type of investor is related to high yields of risk free securities denominated in dinars, as well as the perception of future movements of dinar exchange rate related to currency that serves as source of investment. The consequences of carry trade may significantly influence exchange rate movements when monetary policy has limited facilities to combat negative and sudden shocks.

  2. Evidence and speculation: reimagining approaches to architecture and research within the paediatric hospital.

    Science.gov (United States)

    McLaughlan, Rebecca; Pert, Alan

    2017-11-25

    As the dominant research paradigm within the construction of contemporary healthcare facilities, evidence-based design (EBD) will increasingly impact our expectations of what hospital architecture should be. Research methods within EBD focus on prototyping incremental advances and evaluating what has already been built. Yet medical care is a rapidly evolving system; changes to technology, workforce composition, patient demographics and funding models can create rapid and unpredictable changes to medical practice and modes of care. This dynamism has the potential to curtail or negate the usefulness of current best practice approaches. To imagine new directions for the role of the hospital in society, or innovative ways in which the built environment might support well-being, requires a model that can project beyond existing constraints. Speculative design employs a design-based research methodology to imagine alternative futures and uses the artefacts created through this process to enable broader critical reflection on existing practices. This paper examines the contribution of speculative design within the context of the paediatric hospital as a means of facilitating critical reflection regarding the design of new healthcare facilities. While EBD is largely limited by what has already been built, speculative design offers a complementary research method to meet this limitation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. The end of what? Phenomenology vs. speculative realism

    DEFF Research Database (Denmark)

    Zahavi, Dan

    2016-01-01

    Phenomenology has recently come under attack from proponents of speculative realism. In this paper, I present and assess the criticism, and argue that it is either superficial and simplistic or lacks novelty.......Phenomenology has recently come under attack from proponents of speculative realism. In this paper, I present and assess the criticism, and argue that it is either superficial and simplistic or lacks novelty....

  4. Speculative Considerations about Some Cardiology Enigmas.

    Science.gov (United States)

    Evora, Paulo Roberto Barbosa; Schmidt, Andre; Arcêncio, Livia; Marin-Neto, José Antonio

    2017-01-01

    Enigmas often lead to hypotheses and speculations. For this reason, especially for the sake of the reader's motivation, we opted for the plain discussion of some cardiology enigmas. The present text was aimed to discuss speculatively some cardiology enigmas. Text was freely designed in the context of coronary artery and heart valve diseases. The results were presented as the combination enigma/hypothesis. 1) The absence of arteriosclerosis in intramyocardial coronary arteries/ endothelium-myocardial interaction (crosstalk); 2) The unique and always confirmed superior evolution of the internal thoracic artery as coronary graft/ higher NO basal release 3) The prophylactic left internal thoracic artery graft in mildlystenosed coronary lesions/need of more accurate functional imaging techniques; 4) The high incidence of perioperative atrial fibrillation in patients with coronary artery disease/atrial ischemia associated to left circumflex coronary lesions; 5) The handling of disease-free saphenous vein grafts at the time of reoperation/biological serendipity with graft vein segments; 6) The possible aortic stenosis protection against coronary artery disease/ endothelium-myocardium interaction (crosstalk) improving NO release. The discussed topics associated with their respective speculative hypothesis remain as enigmas, but would become motivations for investigations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  5. [Testing a Model to Predict Problem Gambling in Speculative Game Users].

    Science.gov (United States)

    Park, Hyangjin; Kim, Suk Sun

    2018-04-01

    The purpose of the study was to develop and test a model for predicting problem gambling in speculative game users based on Blaszczynski and Nower's pathways model of problem and pathological gambling. The participants were 262 speculative game users recruited from seven speculative gambling places located in Seoul, Gangwon, and Gyeonggi, Korea. They completed a structured self-report questionnaire comprising measures of problem gambling, negative emotions, attentional impulsivity, motor impulsivity, non-planning impulsivity, gambler's fallacy, and gambling self-efficacy. Structural Equation Modeling was used to test the hypothesized model and to examine the direct and indirect effects on problem gambling in speculative game users using SPSS 22.0 and AMOS 20.0 programs. The hypothetical research model provided a reasonable fit to the data. Negative emotions, motor impulsivity, gambler's fallacy, and gambling self-efficacy had direct effects on problem gambling in speculative game users, while indirect effects were reported for negative emotions, motor impulsivity, and gambler's fallacy. These predictors explained 75.2% problem gambling in speculative game users. The findings suggest that developing intervention programs to reduce negative emotions, motor impulsivity, and gambler's fallacy, and to increase gambling self-efficacy in speculative game users are needed to prevent their problem gambling. © 2018 Korean Society of Nursing Science.

  6. Why Meillassoux’s Speculative Materialism Struggles with Ancestrality

    OpenAIRE

    Ciprian Jeler

    2014-01-01

    This paper shows that Quentin Meillassoux’s speculative materialism doesn’t offer us the means to account for the ancestral statements that the modern sciences produce, i.e. for the scientific statements about events preceding all forms of life. An analysis of the reasons why Meillassoux thinks that the problem of ancestrality problematizes the contemporary self-evidence of correlationism is first offered. The results of this analysis are then applied to speculative materialism itself and the...

  7. Oil prices and speculative bubbles: empirical evidence from WTI markets; Precos do petroleo e bolhas especulativas: algumas evidencias para o mercado de WTI

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Mileno [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Curso de Pos-Graduacao em Economia; PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The purpose of this work is to gather some evidence about the relationship between crude prices and speculation in oil futures and options markets focusing on WTI markets. In order to shed some light on this link, a brief characterization of what a speculative bubble is and how it works is given. It is also shown that the major reason behind the great inflow of capital into oil derivatives markets is that they became much more attractive to investors than other financial markets (i.e. stocks and bonds) between 2000 and 2007. The reasoning behind the speculative bubble argument is stated and a brief discussion about the strategies commercials and non-commercials adopted in WTI futures and options markets during 1995-2007 period is made. We confront this reasoning with the evidence from the non-commercial net positions and WTI prices from 2003 to 2007 and make some econometric tests for the hypotheses that changes in these positions affect prices and for the presence of a speculative bubble in WTI markets. Our analysis shows no clear linkage between oil prices and non-commercials net positions in the way the 'bubble theory' argues and points to a possible problem of asymmetric information in the oil markets. (author)

  8. Oil prices and speculative bubbles: empirical evidence from WTI markets; Precos do petroleo e bolhas especulativas: algumas evidencias para o mercado de WTI

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Mileno [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Curso de Pos-Graduacao em Economia; PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The purpose of this work is to gather some evidence about the relationship between crude prices and speculation in oil futures and options markets focusing on WTI markets. In order to shed some light on this link, a brief characterization of what a speculative bubble is and how it works is given. It is also shown that the major reason behind the great inflow of capital into oil derivatives markets is that they became much more attractive to investors than other financial markets (i.e. stocks and bonds) between 2000 and 2007. The reasoning behind the speculative bubble argument is stated and a brief discussion about the strategies commercials and non-commercials adopted in WTI futures and options markets during 1995-2007 period is made. We confront this reasoning with the evidence from the non-commercial net positions and WTI prices from 2003 to 2007 and make some econometric tests for the hypotheses that changes in these positions affect prices and for the presence of a speculative bubble in WTI markets. Our analysis shows no clear linkage between oil prices and non-commercials net positions in the way the 'bubble theory' argues and points to a possible problem of asymmetric information in the oil markets. (author)

  9. Dark pedagogy – Speculative Realism and Environmental and sustainability education

    DEFF Research Database (Denmark)

    Lysgaard, Jonas Andreasen; Bengtssen, Stefan; Laugesen, Martin

    2018-01-01

    such as correlationism, hyperobjects, object oriented ontology, undermining, overmining and duomining in order to develop a dark pedagogy that could draw on insights from speculative realism and develop the key concepts and discussions within ESE. Based on inspiration from speculative realism a dark pedagogy could...

  10. Contrarian Speculation

    DEFF Research Database (Denmark)

    Bondo Hansen, Kristian

    into account the seemingly irrational behavior of the market crowd. This article’s focal point is the ‘Vermont Ruminator’ Humphrey B. Neill’s conceptualization of ‘The Theory of Contrary Opinion’, a market theory preconditioning the existence of a market crowd as an inherent part of financial markets......This article examines the efforts made in early 20th century novels and investment handbooks to describe allegedly irrational behavior in financial markets, via the employment of late 19th century crowd psychology and the vocabulary that grew out of this theoretical tradition. Crowd psychology...... of ‘problematization’, the article analysis and examines Neill’s contrarian speculation philosophy as a certain field of experience offering an answer to a concrete problem concerning seemingly irrational behavior and inexplicable fluctuations in financial markets. The aim of the article is to understand how ideas...

  11. Design of the digitizing beam position limit detector

    International Nuclear Information System (INIS)

    Merl, R.

    1998-01-01

    The Digitizing Beam Position Limit Detector (DBPLD) is designed to identify and react to beam missteering conditions in the Advanced Photon Source (APS) storage ring. The high power of the insertion devices requires these missteering conditions to result in a beam abort in less than 2 milliseconds. Commercially available beam position monitors provide a voltage proportional to beam position immediately upstream and downstream of insertion devices. The DBPLD is a custom VME board that digitizes these voltages and interrupts the heartbeat of the APS machine protection system when the beam position exceeds its trip limits

  12. What do we know about speculation in the CDS market?

    NARCIS (Netherlands)

    L. Norden (Lars); K. Radoeva (Kristina)

    2012-01-01

    textabstractWe measure speculation in the CDS market and investigate its determinants. The CDS volume on a firm that exceeds its outstanding debt (= naked CDS) indicates speculation since hedging can be ruled out. Using weekly CDS trading volume data for actively traded U.S. firms during 2008-2012,

  13. Garden of cosmic speculation

    CERN Document Server

    Jencks, Charles

    2005-01-01

    This book tells the story of one of the most important gardens in Europe, created by the architectural critic and designer Charles Jencks and his late wife, the landscape architect and author Maggie Keswick. The Garden of Cosmic Speculation is a landscape that celebrates the new sciences of complexity and chaos theory and consists of a series of metaphors exploring the origins, the destiny and the substance of the Universe. The book is illustrated with year-round photography, bringing the garden's many dimensions vividly to life.

  14. Currency speculation and dollar fluctuations

    Directory of Open Access Journals (Sweden)

    Stephan Schulmeister

    1988-12-01

    Full Text Available In this study the reasons behind the wide fluctuations of the dollar exchange rate following the breakdown of the Bretton Woods system, for the most part unexplained by the prevailing exchange rate theories, are explored. To do so, the author investigates the exchange rate between the two most traded currencies, the dollar and the deutschemark, from 1973 to 1988. In the first part, the pattern of the daily exchange rate movements is examined to show that a sequence of upward and downward trends interrupted by non-directional movements is typical of exchange rate dynamics in the short run. Moreover, this pattern is systemically exploited through currency speculation, particularly through the use of “technical analysis”. In the second part, the author focuses on the medium-term, arguing that fluctuations can be explained as the result of interacting disequilibria in the goods and asset markets. Although currency speculation has been systemically profitable for most currencies, it should be considered to be destabilizing since the sequence of price runs caused large and persistent deviations of exchange rates from their equilibrium values (purchasing power parity.

  15. The Home of the Tiger: Economic Speculation and the Ethics of Habitation

    Directory of Open Access Journals (Sweden)

    Jason Matthew Buchanan

    2014-01-01

    Full Text Available In Ireland, the "home" has a long tradition as a powerful spatial signifier, capable of expressing a range of social, aesthetic, and political interactions. Historically, home ownership in Ireland was not only a measure of working-and-middle-class respectability, but also a symbol of national independence that stood in opposition to a colonial history of dispossession. Throughout the Celtic Tiger, however, the ideas of what constituted the "home" were transformed by a speculative form of capitalism that recreated domestic space as a fluctuating (and valuable commodity. By centralizing the connection of urban space to capitalism, speculation opens the domestic spaces of the home to the processes of speculation and devaluation.Essentially, my argument analyzes how changing the economic parameters of domestic space creates a concomitant change in how homes are figured in the Irish cultural lexicon. This change represents a cognitive speculation where the speculative value of a home, as a commodity is what confers an authentic social status on the homeowner. Any ethical concerns related to domestic space, both its use and value, are superseded by its ability to generate capital via a speculative evaluation. Through the connection of spatial and cultural transformation, my paper furthers current discussions in Irish studies that analyze the dramatic impact, and aftermath, of the Tiger. The literary response to speculation, found in analyses of Deidre Madden and Anne Haverty, frame speculation as a parody of communal life that eliminates any real interpersonal relationships in a wave of postmodern alienation. Finally, my paper articulates how the lasting damage that followed the collapse of the Tiger altered the way the Irish understood the concepts and realities of the "home". 

  16. Challenging Speculation about "Dewey's Racialized Visions"

    Science.gov (United States)

    Eldridge, Michael

    2010-01-01

    In this essay Michael Eldridge maintains that Frank Margonis has in a recent article ill-advisedly speculated about John Dewey's pedagogy, suggesting that his "racialized visions" of students and classroom communities involve a "false universalism" that is problematic for our multicultural society. Based on this understanding, Margonis concludes…

  17. The Role of Speculative Factor in the Indonesian Stock Price Determination

    Directory of Open Access Journals (Sweden)

    Soemarso Slamet Rahardjo

    2015-04-01

    Full Text Available This study observes the speculative element in the price determination and its mean reverting pattern. The existence of speculative element in the Indonesian stock market price determination was proven. Exponential Generalized Auto Regressive Conditional Heteroscedasticity (EGARCH method indicates the non-stationary process of the residuals. There are systematic as well as unsystematic component embedded in the speculative behavior. Vector Error Correction Model (VECM concludes that prices contain volatilities in the short run, but, it will revert to the mean in the long run. Investors’ behavior are neutral toward expected gain vis a vis losses in a stock trading.

  18. Speculation in Fixed Futures

    DEFF Research Database (Denmark)

    Puri, Stine Simonsen

    . The thesis focuses on the history of horse racing in India, modes of prediction, friendships among bettors and bookmakers, the interpretation of and work with odds, and the coexistence of legal and illegal economies. The main argument of the study is that the Delhi racecourse is perceived as a site...... knowledge. These speculations are located in the context of an Indian economy, while parallels to global finance are drawn. The thesis follows a number of bettors in their daily life inside and outside the racecourse. Furthermore, it traces the development of various technologies central to betting...

  19. Crowds and Speculation

    DEFF Research Database (Denmark)

    Bondo Hansen, Kristian

    and crowd phenomena in order to fully understand how markets were perceived and conceptualised in the given historical period. Inspired by Michel Foucault’s reflections on the analysis of problematisations, the dissertation explores how practical, academic and popular accounts of financial markets...... problematised (i.e. reflected upon, contested and responded to) various crowd phenomena as they occurred in the markets. As part of the historical exposition, the dissertation examines how financial writers employed tropes and terminology from late nineteenth century crowd theories when describing and seeking....... Drawing on an archive of handbooks on how to become a successful investor or speculator, scholarly work on financial markets (from the academic fields of economics, sociology and psychology) as well as a range of popular (fictional and non-fictional) textual accounts of trading in financial markets...

  20. Speculative prototypes and exogenous ethnographies: Experiencing relationships beyond the human

    DEFF Research Database (Denmark)

    Jönsson, Li; Ulv Lenskjold, Tau

    2017-01-01

    This article deals with the role that speculative design prototypes have as means to intervene in contexts of everyday life in order to explore, and possibly facilitate, new types of relationships between human and non-human beings. Focusing on an off-centered design of the human, it seeks to exp...... to explore what types of new possibilities may arise when speculation in design meets the practice of doing what might be termed an "exogenous ethnography"....

  1. Banking on Extinction: Endangered Species and Speculation

    NARCIS (Netherlands)

    Mason, C.; Bulte, E.H.; Horan, R.D.

    2012-01-01

    Many wildlife commodities, such as tiger bones, bear bladders, ivory, and rhino horn, have been stockpiled in large quantities by speculators who expect that future price increases justify forgoing the interest income associated with current sales. When supply from private stores competes with

  2. Banking on extinction : Endangered species and speculation

    NARCIS (Netherlands)

    Mason, C.; Bulte, E.H.; Horan, R.D.

    2012-01-01

    Many wildlife commodities, such as tiger bones, bear bladders, ivory, and rhino horn, have been stockpiled in large quantities by speculators who expect that future price increases justify forgoing the interest income associated with current sales. When supply from private stores competes with

  3. The Limits of Exercise Physiology: From Performance to Health.

    Science.gov (United States)

    Gabriel, Brendan M; Zierath, Juleen R

    2017-05-02

    Many of the established positive health benefits of exercise have been documented by historical discoveries in the field of exercise physiology. These investigations often assess limits: the limits of performance, or the limits of exercise-induced health benefits. Indeed, several key findings have been informed by studying highly trained athletes, in addition to healthy or unhealthy people. Recent progress has been made in regard to skeletal muscle metabolism and personalized exercise regimes. In this perspective, we review some of the historical milestones of exercise physiology, discuss how these inform contemporary knowledge, and speculate on future questions. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Supply Chain Postponement and Speculation Strategies: How to choose the right strategy

    DEFF Research Database (Denmark)

    Pagh, Janus Dóre; Cooper, Martha

    1998-01-01

    Only a few substaantial efforts have been made to operationalize the theory of postponement and speculation in a way useful to managerial decision making. This paper identifies generic supply chain postpoenment and speculations strategies and proveide managers with a diagnostic and normative...

  5. Managing contamination delay to improve Timing Speculation architectures

    Directory of Open Access Journals (Sweden)

    Naga Durga Prasad Avirneni

    2016-08-01

    Full Text Available Timing Speculation (TS is a widely known method for realizing better-than-worst-case systems. Aggressive clocking, realizable by TS, enable systems to operate beyond specified safe frequency limits to effectively exploit the data dependent circuit delay. However, the range of aggressive clocking for performance enhancement under TS is restricted by short paths. In this paper, we show that increasing the lengths of short paths of the circuit increases the effectiveness of TS, leading to performance improvement. Also, we propose an algorithm to efficiently add delay buffers to selected short paths while keeping down the area penalty. We present our algorithm results for ISCAS-85 suite and show that it is possible to increase the circuit contamination delay by up to 30% without affecting the propagation delay. We also explore the possibility of increasing short path delays further by relaxing the constraint on propagation delay and analyze the performance impact.

  6. A discussion of stock market speculation by Pierre-Joseph Proudhon

    OpenAIRE

    Jean-Claude Juhel; Dominique Dufour

    2010-01-01

    International audience; The object of this contribution is to present the ideas behind the thinking of the French economist Pierre-Joseph Proudhon (1809-1865) in relation to the causes and effects of Stock market speculation. It is based upon the works of this author but particularly on his “Manuel du spéculateur à la Bourse” (Stock Market Speculator Manual) edited in 1857 in Paris. Compared to the markets of today, however, the stock market described by Proudhon appears embryonic. Neverthele...

  7. Performance enhancement of various real-time image processing techniques via speculative execution

    Science.gov (United States)

    Younis, Mohamed F.; Sinha, Purnendu; Marlowe, Thomas J.; Stoyenko, Alexander D.

    1996-03-01

    In real-time image processing, an application must satisfy a set of timing constraints while ensuring the semantic correctness of the system. Because of the natural structure of digital data, pure data and task parallelism have been used extensively in real-time image processing to accelerate the handling time of image data. These types of parallelism are based on splitting the execution load performed by a single processor across multiple nodes. However, execution of all parallel threads is mandatory for correctness of the algorithm. On the other hand, speculative execution is an optimistic execution of part(s) of the program based on assumptions on program control flow or variable values. Rollback may be required if the assumptions turn out to be invalid. Speculative execution can enhance average, and sometimes worst-case, execution time. In this paper, we target various image processing techniques to investigate applicability of speculative execution. We identify opportunities for safe and profitable speculative execution in image compression, edge detection, morphological filters, and blob recognition.

  8. Option Price Estimations and Speculative Trading In Knowledge Society

    Directory of Open Access Journals (Sweden)

    Ovidiu TURCOANE

    2012-01-01

    Full Text Available Derivatives market has known an enormous and continuous development from the late 1970s, thanks to the most celebrated Black-Scholes-Merton formula. The impact on global economy is also tremendous, but due to the high leverage of speculative option trading there is a perpetual danger of economic collapse. This paper gives a short description of knowledge society and proposes methods for option price estimation based on implied volatility, skewness and kurtosis. ‘Free-lunch’ is hardly achievable if one predicts the option price using the knowledgeable information from the market and there is almost impossible to speculate, rather than to hedge, when trading option.

  9. Econometrics as evidence? Examining the 'causal' connections between financial speculation and commodities prices.

    Science.gov (United States)

    Williams, James W; Cook, Nikolai M

    2016-10-01

    One of the lasting legacies of the financial crisis of 2008, and the legislative energies that followed from it, is the growing reliance on econometrics as part of the rulemaking process. Financial regulators are increasingly expected to rationalize proposed rules using available econometric techniques, and the courts have vacated several key rules emanating from Dodd-Frank on the grounds of alleged deficiencies in this evidentiary effort. The turn toward such econometric tools is seen as a significant constraint on and challenge to regulators as they endeavor to engage with such essential policy questions as the impact of financial speculation on food security. Yet, outside of the specialized practitioner community, very little is known about these techniques. This article examines one such econometric test, Granger causality, and its role in a pivotal Dodd-Frank rulemaking. Through an examination of the test for Granger causality and its attempts to distill the causal connections between financial speculation and commodities prices, the article argues that econometrics is a blunt but useful tool, limited in its ability to provide decisive insights into commodities markets and yet yielding useful returns for those who are able to wield it.

  10. The value and pitfalls of speculation about science and technology in bioethics: the case of cognitive enhancement.

    Science.gov (United States)

    Racine, Eric; Martin Rubio, Tristana; Chandler, Jennifer; Forlini, Cynthia; Lucke, Jayne

    2014-08-01

    In the debate on the ethics of the non-medical use of pharmaceuticals for cognitive performance enhancement in healthy individuals there is a clear division between those who view "cognitive enhancement" as ethically unproblematic and those who see such practices as fraught with ethical problems. Yet another, more subtle issue, relates to the relevance and quality of the contribution of scholarly bioethics to this debate. More specifically, how have various forms of speculation, anticipatory ethics, and methods to predict scientific trends and societal responses augmented or diminished this contribution? In this paper, we use the discussion of the ethics of cognitive enhancement to explore the positive and negative contribution of speculation in bioethics scholarship. First, we review and discuss how speculation has relied on different sets of assumptions regarding the non-medical use of stimulants, namely: (1) terminology and framing; (2) scientific aspects such as efficacy and safety; (3) estimates of prevalence and consequent normalization; and (4) the need for normative reflection and regulatory guidelines. Second, three methodological guideposts are proposed to alleviate some of the pitfalls of speculation: (1) acknowledge assumptions more explicitly and identify the value attributed to assumptions; (2) validate assumptions with interdisciplinary literature; and (3) adopt a broad perspective to promote more comprehensive reflection. We conclude that, through the examination of the controversy about cognitive enhancement, we can employ these methodological guideposts to enhance the value of contributions from bioethics and minimize potential epistemic and practical pitfalls in this case and perhaps in other areas of bioethical debate.

  11. Speculative prototypes and alien ethnographies: Experimenting with relations beyond the human

    DEFF Research Database (Denmark)

    Jönsson, Li; Ulv Lenskjold, Tau

    2017-01-01

    This article concerns the role of speculative design prototypes as a means of intervening into everyday life contexts in order to explore, and possibly enable, new kinds of relations between humans and non-human beings. By addressing a human de-centring through design, the aim is to explore what ...... kind of new possibilities might arise when design speculation meets a practice of doing what can be called an ‘alien ethnography’....

  12. On the Efficient Exploitation of Speculation under Data flow Paradigms of Control

    Science.gov (United States)

    1989-05-19

    use. Une maison est une machine 6 habiter. - LE CORBUSIER , Vers une architecture 110 Chapter 5 Experiments and Results W e will journey in this chapter...occupation. le replied: "a speculator." - A. MICHAEL LIPPER, Back to the Future: The Case for Speculation, Baruch-Style 25 Chapter 2 Language and System

  13. Impact of speculator's expectations of returns and time scales of investment on crude oil price behaviors

    International Nuclear Information System (INIS)

    He, Ling-Yun; Fan, Ying; Wei, Yi-Ming

    2009-01-01

    Based on time series of crude oil prices (daily spot), this paper analyses price fluctuation with two significant parameters τ (speculators' time scales of investment) and ε (speculators' expectations of return) by using Zipf analysis technique, specifically, by mapping τ-returns of prices into 3-alphabeted sequences (absolute frequencies) and 2-alphabeted sequences (relative frequencies), containing the fundamental information of price fluctuations. This paper empirically explores parameters and identifies various types of speculators' cognition patterns of price behavior. In order to quantify the degree of distortion, a feasible reference is proposed: an ideal speculator. Finally, this paper discusses the similarities and differences between those cognition patterns of speculators' and those of an ideal speculator. The resultant analyses identify the possible distortion of price behaviors by their patterns. (author)

  14. Speculation on commodities futures markets and destabilization of global food prices: exploring the connections.

    Science.gov (United States)

    Ghosh, Jayati; Heintz, James; Pollin, Robert

    2012-01-01

    In December 2010, the United Nations Food and Agriculture Organization's Food Price Index surpassed its previous peak of June 2008, and prices remained at this level through September 2011. This pattern is creating justified fears of a renewal or intensification of the global food crisis. This paper reviews arguments and evidence to inform debates on how to regulate commodity futures markets in the face of such price volatility and sustained high prices. We focus on the relationship between market liquidity and price patterns in asset markets in general and in commodities futures markets in particular, as well as the relationship between spot and futures market prices for food. We find strong evidence supporting the need to limit huge increases in trading volume on futures markets through regulations. We find that arguments opposing regulation are not supported. We find no support for the claim that liquidity in futures markets stabilizes prices at "fundamental" values or that spot market prices are free of any significant influence from futures markets. Given these results, the most appropriate position for regulators is precautionary: they should enact and enforce policies capable of effectively dampening excessive speculative trading on the commodities markets for food.

  15. Turned On / Turned Off: Speculating on the Microchip-based Contraceptive Implant

    DEFF Research Database (Denmark)

    Homewood, Sarah; Heyer, Clint

    2017-01-01

    disruptions of "the pill". Framed as interactive technology, we speculate on the design space of controllable implanted contraceptives. We explored existing implanted contraceptives through a performance ethnography of their implantation. Inspiration from this process informed a speculative video of living...... with controllable implants and a guide for healthcare professionals. These materials, along with expert presentations, backgrounded a design workshop in which participants unpacked issues around controllable contraceptive implants. Participants created and roleplayed physical mock-ups of controllers, manifesting...

  16. Speculative 'before' the Turn: Reintroducing Feminist Materialist Performativity

    NARCIS (Netherlands)

    Thiele, K.C.; van der Tuin, Iris; Asberg, C.

    2015-01-01

    This is a moment for new conversations and new synergies. Whilst a wealth of contemporary speculative materialisms is currently circulating in academia, art, and activism, in this article we would like to focus upon a few ethico-political stakes in the different, loosely affiliated conceptions of

  17. The role of market fundamentals and speculation in recent price changes for crude oil

    International Nuclear Information System (INIS)

    Kaufmann, Robert K.

    2011-01-01

    I hypothesize that the price spike and collapse of 2007-2008 are driven by both changes in both market fundamentals and speculative pressures. Contrary to arguments for a demand shock, I hypothesize that prices rise sharply in 2007-2008 because ongoing growth in Chinese oil demand runs into a sudden and unexpected halt to a decade long increase in non-OPEC production. This caused a loss of OPEC spare capacity because increased demand for OPEC production runs ahead of increases in OPEC capacity. These changes are reinforced by speculative expectations. Although difficult to measure directly, I argue for the role of speculation based on the following: (1) a significant increase in private US crude oil inventories since 2004; (2) repeated and extended break-downs (starting in 2004) in the cointegrating relationship between spot and far month future prices that are inconsistent with the law of one price and arbitrage opportunities; and (3) statistical and predictive failures by an econometric model of oil prices that is based on market fundamentals. These changes are related to the behavior and impact of noise traders on asset prices to sketch mechanisms by which speculative expectations can affect crude oil prices. - Research Highlights: → The 2007-2009 spike and collapse in oil prices is caused by a combination of market fundamentals and speculative expectations. → The rise is caused by an unexpected hiatus in non-OPEC oil production, not a sudden increase in demand. → The role of speculation is suggested by an increase in oil inventories, which reverses a twenty year period of declines, a decoupling between spot and futures prices, which violates the law of one price, and a breakdown of empirical models of oil prices based solely on market fundamentals. → Speculative expectations affect oil prices via noise traders, who create a risk that deters rational arbitrageurs from betting against them.

  18. Risk-premia, Carry-trade Dynamics, and Economic Value of Currency Speculation

    DEFF Research Database (Denmark)

    Wagner, Christian

    2012-01-01

    In this paper, we derive the dynamics and assess the economic value of currency speculation by formalizing the concept of a trader inaction range. We show that exchange rate returns comprise a time-varying risk-premium and that uncovered interest parity (UIP) holds in a speculative sense. The often......-cited ‘forward bias puzzle’ originates from the omission of the risk-premium in standard UIP tests. Consistent with its popularity among market professionals, the carry-trade strategy can be rationalized as it systematically collects risk-premia, however, the economic value generated by bilateral carry-trades...

  19. Historical Drawbacks of Limited Liability

    Directory of Open Access Journals (Sweden)

    Denis Boyle

    2016-07-01

    Full Text Available Limited liability is a human invention which has facilitated enormous economic growth around the world, particularly since the time of its general application in advanced countries during the nineteenth century. The individual legal identity of companies, coupled with the limited liability of their owners, has provided protection for investors from the risks associated with their investments. It has thus contributed to increase the sources of capital available to finance projects which might otherwise have been considered unviable. However, the legal protection offered to investors has negative consequences for other participants in economies. Speculation in stock markets often damages society. It is very important to study the drawbacks of limited liability and to suggest modifications to achieve a more stable, less volatile, economic growth in the world. Although this article goes to some lengths to recognise the work of authors who emphasise the positive historical economic contribution of limited lability, its main objective is to provoke a reflection around texts which point out the drawbacks and propose solutions.

  20. Speculative phenomena impact on oil prices formation

    International Nuclear Information System (INIS)

    Thomas, Matthieu

    2009-01-01

    Crude oil prices evolution between 2007 and 2009 has been the centre of a major controversy. This paper aims to understand the structural changes which happened on the oil market during the past decade. Analysis is focused on the consequences on oil prices of growing financial investments in commodities. More specifically, emphasis is set on little commented facts that comfort the hypothesis of a speculative bubble between 2007 and 2009

  1. Toward quantum-limited position measurements using optically levitated microspheres

    International Nuclear Information System (INIS)

    Libbrecht, Kenneth G.; Black, Eric D.

    2004-01-01

    We propose the use of optically levitated microspheres as test masses in experiments aimed at reaching and potentially exceeding the standard quantum limit for position measurements. Optically levitated microspheres have low mass and are essentially free of suspension thermal noise, making them well suited for experimentally testing our understanding of quantum-limited measurements

  2. Toward quantum-limited position measurements using optically levitated microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Libbrecht, Kenneth G.; Black, Eric D

    2004-01-26

    We propose the use of optically levitated microspheres as test masses in experiments aimed at reaching and potentially exceeding the standard quantum limit for position measurements. Optically levitated microspheres have low mass and are essentially free of suspension thermal noise, making them well suited for experimentally testing our understanding of quantum-limited measurements.

  3. Aminoglycoside antibiotics and autism: a speculative hypothesis

    Directory of Open Access Journals (Sweden)

    Manev Hari

    2001-10-01

    Full Text Available Abstract Background Recently, it has been suspected that there is a relationship between therapy with some antibiotics and the onset of autism; but even more curious, some children benefited transiently from a subsequent treatment with a different antibiotic. Here, we speculate how aminoglycoside antibiotics might be associated with autism. Presentation We hypothesize that aminoglycoside antibiotics could a trigger the autism syndrome in susceptible infants by causing the stop codon readthrough, i.e., a misreading of the genetic code of a hypothetical critical gene, and/or b improve autism symptoms by correcting the premature stop codon mutation in a hypothetical polymorphic gene linked to autism. Testing Investigate, retrospectively, whether a link exists between aminoglycoside use (which is not extensive in children and the onset of autism symptoms (hypothesis "a", or between amino glycoside use and improvement of these symptoms (hypothesis "b". Whereas a prospective study to test hypothesis "a" is not ethically justifiable, a study could be designed to test hypothesis "b". Implications It should be stressed that at this stage no direct evidence supports our speculative hypothesis and that its main purpose is to initiate development of new ideas that, eventually, would improve our understanding of the pathobiology of autism.

  4. Stock market speculation: Spontaneous symmetry breaking of economic valuation

    Science.gov (United States)

    Sornette, Didier

    2000-09-01

    Firm foundation theory estimates a security's firm fundamental value based on four determinants: expected growth rate, expected dividend payout, the market interest rate and the degree of risk. In contrast, other views of decision-making in the stock market, using alternatives such as human psychology and behavior, bounded rationality, agent-based modeling and evolutionary game theory, expound that speculative and crowd behavior of investors may play a major role in shaping market prices. Here, we propose that the two views refer to two classes of companies connected through a "phase transition". Our theory is based on (1) the identification of the fundamental parity symmetry of prices (p→-p), which results from the relative direction of payment flux compared to commodity flux and (2) the observation that a company's risk-adjusted growth rate discounted by the market interest rate behaves as a control parameter for the observable price. We find a critical value of this control parameter at which a spontaneous symmetry-breaking of prices occurs, leading to a spontaneous valuation in absence of earnings, similarly to the emergence of a spontaneous magnetization in Ising models in absence of a magnetic field. The low growth rate phase is described by the firm foundation theory while the large growth rate phase is the regime of speculation and crowd behavior. In practice, while large "finite-time horizon" effects round off the predicted singularities, our symmetry-breaking speculation theory accounts for the apparent over-pricing and the high volatility of fast growing companies on the stock markets.

  5. Oil price dynamics and speculation. A multivariate financial approach

    International Nuclear Information System (INIS)

    Cifarelli, Giulio; Paladino, Giovanna

    2010-01-01

    This paper assesses empirically whether speculation affects oil price dynamics. The growing presence of financial operators in the oil markets has led to the diffusion of trading techniques based on extrapolative expectations. Strategies of this kind foster feedback trading that may cause considerable departures of prices from their fundamental values. We investigate this hypothesis using a modified CAPM following Shiller (1984) and Sentana and Wadhwani (1992). First, a univariate GARCH(1,1)-M is estimated assuming the risk premium to be a function of the conditional oil price volatility. The single factor model, however, is outperformed by the multifactor ICAPM (Merton, 1973), which takes into account a larger investment opportunity set. Analysis is then carried out using a trivariate CCC GARCH-M model with complex nonlinear conditional mean equations where oil price dynamics are associated with both stock market and exchange rate behavior. We find strong evidence that oil price shifts are negatively related to stock price and exchange rate changes and that a complex web of time-varying first and second order conditional moment interactions affects both the CAPM and feedback trading components of the model. Despite the difficulties, we identify a significant role played by speculation in the oil market, which is consistent with the observed large daily upward and downward shifts in prices - a clear evidence that it is not a fundamental-driven market. Thus, from a policy point of view - given the impact of volatile oil prices on global inflation and growth - actions that monitor speculative activities on commodity markets more effectively are to be welcomed. (author)

  6. Oil price dynamics and speculation. A multivariate financial approach

    Energy Technology Data Exchange (ETDEWEB)

    Cifarelli, Giulio [University of Florence, Dipartimento di Scienze Economiche, via delle Pandette 9, 50127, Florence (Italy); Paladino, Giovanna [Economics Department, LUISS University (Italy); BIIS International Division (Italy)

    2010-03-15

    This paper assesses empirically whether speculation affects oil price dynamics. The growing presence of financial operators in the oil markets has led to the diffusion of trading techniques based on extrapolative expectations. Strategies of this kind foster feedback trading that may cause considerable departures of prices from their fundamental values. We investigate this hypothesis using a modified CAPM following Shiller (1984) and Sentana and Wadhwani (1992). First, a univariate GARCH(1,1)-M is estimated assuming the risk premium to be a function of the conditional oil price volatility. The single factor model, however, is outperformed by the multifactor ICAPM (Merton, 1973), which takes into account a larger investment opportunity set. Analysis is then carried out using a trivariate CCC GARCH-M model with complex nonlinear conditional mean equations where oil price dynamics are associated with both stock market and exchange rate behavior. We find strong evidence that oil price shifts are negatively related to stock price and exchange rate changes and that a complex web of time-varying first and second order conditional moment interactions affects both the CAPM and feedback trading components of the model. Despite the difficulties, we identify a significant role played by speculation in the oil market, which is consistent with the observed large daily upward and downward shifts in prices - a clear evidence that it is not a fundamental-driven market. Thus, from a policy point of view - given the impact of volatile oil prices on global inflation and growth - actions that monitor speculative activities on commodity markets more effectively are to be welcomed. (author)

  7. Out of Site & Out of Mind: Speculative Historiographies of Techno Trash

    Directory of Open Access Journals (Sweden)

    Mél Hogan

    2015-06-01

    Full Text Available Out of Site & Out of Mind: Speculative Historiographies of Techno Trash by Mel Hogan and Andrea Zeffiro. Our contribution to the “Aesthetics of Trash” introduces an online participatory storytelling project, Speculative Historiographies of Techno Trash (technotrash.org. In its current iteration, technotrash.org is a website through which we are soliciting and featuring personal written reflections on the consumption and disposal of media technologies. Our project goal is to render the material and immaterial residues generated from of our everyday media practices more visible by accentuating the ecological and ethical dilemmas posed by the production, consumption, and disposal of media technologies.

  8. What is nature capable of? Evidence, ontology and speculative medical humanities.

    Science.gov (United States)

    Savransky, Martin; Rosengarten, Marsha

    2016-09-01

    Expanding on the recent call for a 'critical medical humanities' to intervene in questions of the ontology of health, this article develops a what we call a 'speculative' orientation to such interventions in relation to some of the ontological commitments on which contemporary biomedical cultures rest. We argue that crucial to this task is an approach to ontology that treats it not as a question of first principles, but as a matter of the consequences of the images of nature that contemporary biomedical research practices espouse when they make claims to evidence, as well as the possible consequences of imagining different worlds in which health and disease processes partake. By attending to the implicit ontological assumptions involved in the method par excellence of biomedical research, namely the randomised controlled trial (RCT), we argue that the mechanistic ontology that tacitly informs evidence-based biomedical research simultaneously authorises a series of problematic consequences for understanding and intervening practically in the concrete realities of health. As a response, we develop an alternative ontological proposition that regards processes of health and disease as always situated achievements. We show that, without disqualifying RCT-based evidence, such a situated ontology enables one to resist the reduction of the realities of health and disease to biomedicine's current forms of explanation. In so doing, we call for medical humanities scholars to actively engage in the speculative question of what nature may be capable of. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. Vital New Matters: The Speculative Turn in the Study of Religion and Gender

    Directory of Open Access Journals (Sweden)

    Paul Reid-Bowen

    2011-08-01

    Full Text Available This article provides an introduction to a new trend in continental philosophy, the turn toward metaphysics, realism and speculative philosophy.  This stands in sharp contrast with the anitrealist and correlationist traditions that have held sway since Kant’s Copernican Revolution in 1781.  It is claimed that the study of religion and gender has been shaped by the antirealist legacy of Kant, but there are good reasons for taking account of the new ‘speculative turn’.  Two examples from the leading exponent of this turn, speculative realism, are introduced, and some provisional notes toward applying these to the gender-critical turn in the study of religion are considered.  Research notes on the current state of the Goddess movement serve as a test case for the introduction of an object-oriented ontology into religious and gender studies.

  10. Beyond speculative robot ethics: a vision assessment study on the future of the robotic caretaker.

    Science.gov (United States)

    van der Plas, Arjanna; Smits, Martijntje; Wehrmann, Caroline

    2010-11-01

    In this article we develop a dialogue model for robot technology experts and designated users to discuss visions on the future of robotics in long-term care. Our vision assessment study aims for more distinguished and more informed visions on future robots. Surprisingly, our experiment also led to some promising co-designed robot concepts in which jointly articulated moral guidelines are embedded. With our model, we think to have designed an interesting response on a recent call for a less speculative ethics of technology by encouraging discussions about the quality of positive and negative visions on the future of robotics.

  11. Positive uncertainty: The benefit of the doubt in advertising

    NARCIS (Netherlands)

    Ketelaar, P.E.; Riet, J.P. van 't; Thorbjornsen, H.; Buijzen, M.A.

    2018-01-01

    Positive uncertainty refers to uncertainty surrounding an anticipated positive outcome. It provides consumers with the opportunity to imagine and speculate on a product's or experience's potentially positive characteristics. Research has shown that when uncertainty is associated with something

  12. Of Men, Machines and Apocalypses: Masculine Anxieties in Indian Speculative Fiction

    Directory of Open Access Journals (Sweden)

    Dibyadyuti Roy

    2015-07-01

    Full Text Available Exploding bombs embedded with catastrophic potential have remained central to our eschatological conceptualizations for more than a century. Future war fiction—a key sub-genre of speculative fiction—in building upon this obsession introduces us to unforeseen apocalyptic settings, which are brought forth through a nexus between gendered bodies and destructive military machinery. In underscoring the decidedly masculine nature of future war fiction, this article explores depictions of anxious postcolonial masculinity within the little-explored terrain of Indian speculative fiction. Apocalyptic settings in these texts, I argue, provide a topos for enacting postcolonial masculine anxieties, which are subsequently countered through making male bodies contingent on the volatile performances of destructive military technology. In utilizing R.W Connell’s conceptualization of “hegemonic masculinity,” I explore the reasons behind the emergence of postcolonial masculine insecurities, which, I argue, results from India’s colonial history and its continued legacy within the subcontinent. Finally, my examination of representative Indian speculative texts, namely Mainak Dhar’s Line of Control (2009 and Sami Ahmad Khan’s Red Jihad (2012 emphasizes that making hegemonic postcolonial masculinity contingent on the destructive capabilities of military technology results in unstable and threatening masculine performances; much like the unpredictable nature of war machinery highlighted in these texts.

  13. Rational Speculative Bubble Size in Gold, Hang Seng, S&P 500 and Nikkei 225 Index During Year 2008 to 2016

    Science.gov (United States)

    Borhan, Nurharyanti; Halim, Nurfadhlina Abdul; Amir, W. Ahmad Wan Muhammad

    2017-09-01

    A rational speculative bubble is a surge in asset prices that exceed its intrinsic value. Rational speculative bubbles are among the ascription which may lead to the collapse of an economic system. Rational speculative bubble cannot be created but it comes into existence when assets started to be traded. Financial rational speculative bubble and burst have negative effect on the economy and markets. Financial rational speculative bubbles are difficult to detect. This study aims to shows the size of rational speculative bubble in four markets, which are gold, Hang Seng, S&P500 and Nikkei 225 during year 2008 to 2016. In this study, generalized Johansen-Ledoit-Sornette model are used to find the size of the rational speculative bubble. Bubble detection is important for both sides of macro-economic decision makers and to the trader. Especially for a trading system that requires detailed knowledge about the time and the stage of the bubble burst.

  14. A speculated cause of respiratory inhibition in infants.

    Science.gov (United States)

    Minowa, Hideki; Arai, Ikuyo; Yasuhara, Hajime; Ebisu, Reiko; Ohgitani, Ayako

    2018-10-01

    In our previous studies, we documented that threatened premature labor and asymmetrical intrauterine growth restriction were risk factors for respiratory inhibition. The goal of this study was to determine the cause of respiratory inhibition by considering perinatal risk factors. We examined 1497 infants with a gestational age of 36 weeks or greater. All infants were monitored using pulse oximetry and examined via cranial sonography. Respiratory inhibition was defined as severe hypoxemia caused by respiratory inhibition immediately after crying or gastroesophageal reflux or as a respiratory pause during feeding. We examined the relationships between respiratory inhibition and perinatal factors and speculated on the cause of respiratory inhibition. The median gestational age, birth weight, Apgar score at 1 min, and Apgar score at 5 min of the subjects were 38.9 weeks, 2930 g, 8.0 points, and 9.0 points, respectively. Respiratory inhibition was observed in 422 infants. Lateral ventricle enlargement and increased echogenicity in the ganglionic eminence were observed in 417 and 516 infants, respectively. Respiratory inhibition was significantly correlated with shorter gestational periods, twin pregnancies, lateral ventricle enlargement, and increased echogenicity in the ganglionic eminence. We speculate that umbilical cord compression is a major cause of respiratory inhibition.

  15. A study on the mechanism of speculative attack and the defence strategy of the central bank.

    Directory of Open Access Journals (Sweden)

    Chang-Hyun Yun

    1999-09-01

    Full Text Available We first analyze the concrete mechanism of speculative attack on the foreign exchange market which became very prevalent phenomena during the foreign exchange crisis. When the central bank of the domestic country tries to defend the attack by increasing the interest rate, some problems can arise in that the speculative attacks through foreign exchange options market and/or index futures markets can be very successful due to that policy. So the central bank should pay much attention to the microstructure of the financial markets when the defence strategy against speculative attack is determined.

  16. Elastic stability and the limit of strength

    International Nuclear Information System (INIS)

    Morris Jr., J.W.; Krenn, C.R.; Roundy, D.; Cohen, Marvin L.

    2002-01-01

    The upper limit of strength (the ''theoretical strength'') has been an active subject of research and speculation for the better part of a century. The subject has recently become important, for two reasons. First, given recent advances in ab initio techniques and computing machines, the limits of strength can be calculated with considerable accuracy, making this one of the very few problems in mechanical behavior that can actually be solved. Second, given recent advances in materials engineering, the limits of strength are being approached in some systems, such as hardened or defect-free films, and their relevance is becoming recognized in others. The present paper discusses some interesting results from recent research on the limits of strength, with an intermixture of speculations based on those results. Topics include the inherent nature of {100} cleavage and ''pencil slip'' in bcc metals, the inherent ductility of fcc metals, the anomalous properties of Al, and the possibility of measuring ideal strength with nanoindentation

  17. Speculative Attacks with Multiple Sources of Public Information

    OpenAIRE

    Cornand, Camille; Heinemann, Frank

    2005-01-01

    We propose a speculative attack model in which agents receive multiple public signals. It is characterised by its focus on an informational structure, which sets free from the strict separation between public information and private information. Diverse pieces of public information can be taken into account differently by players and are likely to lead to different appreciations ex post. This process defines players’ private value. The main result is to show that equilibrium uniqueness depend...

  18. NANO supermarket : using speculative design to catalyze a technology debate

    NARCIS (Netherlands)

    Mensvoort, van K.M.; Vos, C.; Wouters, S.; Konrad, K.; Coenen, C.; Dijkstra, A.; Milburn, C.; Lente, van H.

    2013-01-01

    The NANO Supermarket is a mobile exhibition, which presents specula-tive, debate-provoking nanotechnology products that might arrive on the market within the next decades. The products function as scenarios for potential techno-logical futures that invite a broad audience to discuss the impact of

  19. Limits to Arbitrage and Hedging: Evidence from Commodity Markets

    OpenAIRE

    Acharya, Viral V; Lochstoer, Lars; Ramadorai, Tarun

    2009-01-01

    Motivated by the literature on limits-to-arbitrage, we build an equilibrium model of commodity markets in which speculators are capital constrained, and commodity producers have hedging demands for commodity futures. Increases (decreases) in producers' hedging demand (speculators' risk-capacity) increase hedging costs via price-pressure on futures, reduce producers' inventory holdings, and thus spot prices. Consistent with our model, producers' default risk forecasts futures returns, spot pri...

  20. Intertemporal speculation, shortages and the political economy of price reform

    NARCIS (Netherlands)

    van Wijnbergen, S.J.G.

    1992-01-01

    Price controls often focus on commodities that are storable and can thus be used in intertemporal speculation. Second, opposition to dismantling of controls is often based on claims of low supply response, and greatly bolstered if a strong supply response fails to materialise. This is especially

  1. On the maximum drawdown during speculative bubbles

    Science.gov (United States)

    Rotundo, Giulia; Navarra, Mauro

    2007-08-01

    A taxonomy of large financial crashes proposed in the literature locates the burst of speculative bubbles due to endogenous causes in the framework of extreme stock market crashes, defined as falls of market prices that are outlier with respect to the bulk of drawdown price movement distribution. This paper goes on deeper in the analysis providing a further characterization of the rising part of such selected bubbles through the examination of drawdown and maximum drawdown movement of indices prices. The analysis of drawdown duration is also performed and it is the core of the risk measure estimated here.

  2. Speculative Behavior and Heterogeneous Expectations: Theory and Evidence

    OpenAIRE

    Cheolbeom Park

    2002-01-01

    This paper demonstrates that the optimal willingness to pay for a stock is the payoff from holding the stock for one period when investors have different expectations, and that the willingness to pay can be represented as the sum of the expected present value of future dividends and the expected present value of the gap between the future equilibrium price and willingness to pay. This speculative behavior based on the awareness of heterogeneity in expectations is supported by the volatility t...

  3. Fundamental limits to position determination by concentration gradients.

    Directory of Open Access Journals (Sweden)

    Filipe Tostevin

    2007-04-01

    Full Text Available Position determination in biological systems is often achieved through protein concentration gradients. Measuring the local concentration of such a protein with a spatially varying distribution allows the measurement of position within the system. For these systems to work effectively, position determination must be robust to noise. Here, we calculate fundamental limits to the precision of position determination by concentration gradients due to unavoidable biochemical noise perturbing the gradients. We focus on gradient proteins with first-order reaction kinetics. Systems of this type have been experimentally characterised in both developmental and cell biology settings. For a single gradient we show that, through time-averaging, great precision potentially can be achieved even with very low protein copy numbers. As a second example, we investigate the ability of a system with oppositely directed gradients to find its centre. With this mechanism, positional precision close to the centre improves more slowly with increasing averaging time, and so longer averaging times or higher copy numbers are required for high precision. For both single and double gradients, we demonstrate the existence of optimal length scales for the gradients for which precision is maximized, as well as analyze how precision depends on the size of the concentration-measuring apparatus. These results provide fundamental constraints on the positional precision supplied by concentration gradients in various contexts, including both in developmental biology and also within a single cell.

  4. Making, Mending and Growing in Feminist Speculative Fabulations: Design’s Unfaithful Daughters

    DEFF Research Database (Denmark)

    Jönsson, Li; Ståhl, Åsa; Forlano, Laura

    2016-01-01

    Drawing on a recent book by Stengers and Despret (2014), this conversation seeks to consider design research practices around critical and speculative design (Dunne & Raby, 2009, 2013) and speculative fabulation (Haraway, 2011) from a feminist perspective and, in particular, core feminist arguments......’s ethnographic work on gender, stating that “It matters what stories make worlds, what worlds make stories.” Bardzell (2010) describes a feminist HCI methodology as including: a commitment to both scientific and moral objectives, a connection to feminist theory, a deliberate use of methods based on values...... and goals, an empathic relationship with research participants, transparency around the role of the researcher along with their beliefs, co-construction of research, mixed methodologies and reflexivity. This conversation will draw inspiration from critical feminist theory such as Haraway’s cat’s cradle...

  5. The Logic of the Idea and a Speculative Understanding of the State

    Directory of Open Access Journals (Sweden)

    Román Cuartango

    2017-01-01

    Full Text Available The notion of «speculative individual» represents, for Hegel, the philosophical way of apprehending the modern principle of the individual, but reserving for it an ethical perspective, i.e. socially mediated.

  6. Day-­to-­day speculation : designing and wearing dynamic fabric

    NARCIS (Netherlands)

    Mackey, A.M.; Wakkary, R.L.; Wensveen, S.A.G.; Tomico Plasencia, O.; Hengeveld, B.J.

    2017-01-01

    In this paper we describe Greenscreen Dress, a material speculation inquiry that investigates the wearing experience of dynamic fabric in everyday life. In this study the researcher has worn a "greenscreen garment" every day for seven months. Coupled with a chroma-key smartphone application, she has

  7. Past, present, and possible future limits on the photon rest mass

    International Nuclear Information System (INIS)

    Nieto, M.M.

    1992-01-01

    In an historical context, present limits on the photon rest mass are reviewed. More stringent, yet speculative, limits which have been proposed are mentioned. Finally, new theoretical ideas and possible experimental improvements on the present limits are discussed, along with possible relationships between these two areas

  8. Liquidation sales: Land speculation and landscape change

    Science.gov (United States)

    Lazarus, E.

    2012-12-01

    Large-scale land-use transitions can occur with astonishing speed, and landscape stability can change with equal suddenness: for example, the catastrophic dustbowl that paralyzed the Midwestern US in the early 1930s came barely 40 years after the derby for homestead land in Oklahoma in 1889. Some human-landscape systems, like the large prehistoric settlements in the Brazilian Amazon, persisted for centuries without environmental collapse. Others quickly exhausted all of the environmental resources available, as occurred with phosphate mining on the Pacific Island of Nauru. Although abrupt shifts from resource plenty to resource scarcity are theoretically interesting for their complexity, the very real consequences of modern social and environmental boom-bust dynamics can catalyze humanitarian crises. Drawing on historical examples and investigative reporting of current events, I explore the hypothesis that land speculation drives rapid transitions in physical landscapes at large spatial scales. "Land grabs" is one of four core environmental justice and equality issues Oxfam International is targeting in its GROW campaign, citing evidence that foreign investors are buying up vast tracts of land in developing countries, and as a consequence exacerbating food scarcity and marginalization of poor families. Al Jazeera has reported extensively on land-rights disputes in Honduras and investment deals involving foreign ownership of large areas of agricultural land in New Zealand, India, Africa, and South America. Overlapping coverage has also appeared in the New York Times, the Washington Post, the BBC News, the Guardian, and other outlets. Although land itself is only one kind of natural resource, land rights typically determine access to other natural resources (e.g. water, timber, minerals, fossil fuels). Consideration of land speculation therefore includes speculative bubbles in natural-resource markets more broadly. There are categorical commonalities in agricultural

  9. Duration dependence test for rational speculative bubble: the strength and weakness

    OpenAIRE

    Ahmad, Mahyudin

    2012-01-01

    This review highlights the strength and weakness of duration dependence test used by Mokhtar, Nassir and Hassan (2006) to detect the rational speculative bubble in the Malaysian stock market. It is found that despite the test’s strength over the other tests, it is however sensitive to different specifications and therefore may produce contrasting results.

  10. THE LIMITS OF POSITIVE INTERVENTIONS

    Directory of Open Access Journals (Sweden)

    Gonzalo Hervás

    2017-01-01

    Full Text Available Positive interventions have been developed extensively in recent years and they have been tested and applied in very diverse settings. Despite the fact that most of the findings regarding their efficacy can be considered from positive to very positive, the possibility that, in some cases, positive interventions may have unexpected or even iatrogenic effects cannot be discarded. In this article, research from several sources is reviewed in order to inform decisions about what interventions might be inadequate for cases with specific characteristics or vulnerability traits. Finally, the importance of using positive interventions with caution and rigor even when working with individuals who do not have overt problems or psychological disorders is discussed.

  11. Automatic parallelization of while-Loops using speculative execution

    International Nuclear Information System (INIS)

    Collard, J.F.

    1995-01-01

    Automatic parallelization of imperative sequential programs has focused on nests of for-loops. The most recent of them consist in finding an affine mapping with respect to the loop indices to simultaneously capture the temporal and spatial properties of the parallelized program. Such a mapping is usually called a open-quotes space-time transformation.close quotes This work describes an extension of these techniques to while-loops using speculative execution. We show that space-time transformations are a good framework for summing up previous restructuration techniques of while-loop, such as pipelining. Moreover, we show that these transformations can be derived and applied automatically

  12. Detecting position using ARKit II: generating position-time graphs in real-time and further information on limitations of ARKit

    Science.gov (United States)

    Dilek, Ufuk; Erol, Mustafa

    2018-05-01

    ARKit is a framework which allows developers to create augmented reality apps for the iPhone and iPad. In a previous study, we had shown that it could be used to detect position in educational physics experiments and emphasized that the ability to provide position data in real-time was one of the prominent features of this newly emerging technology. In this study, we demonstrate an example of how real-time data acquisition can be employed in educational settings, report some of the limitations of ARKit and how we have overcome these limitations. By means of ARKit or a similar framework, ordinary mobile devices can be adapted for use in microcomputer-based lab activities.

  13. Financial policy and speculative runs with a crawling peg: Argentina 1979-1981

    NARCIS (Netherlands)

    van Wijnbergen, S.J.G.

    1989-01-01

    This paper presents a model of a balance-of-payment crisis and examines the financial policy of the Argentine government in dealing with the speculative runs on the peg between December 1978 and February 1981. The evolution of a crisis when a collapse is not perfectly foreseen; The factors that

  14. Speculations regarding the history of Donum Vitae.

    Science.gov (United States)

    Harvey, J C

    1989-10-01

    In March 1987, the Vatican published Instruction on Respect for Human Life in its Origin and on the Dignity of Procreation, also known as Donum Vitae. Prepared by the Roman Catholic Church's Congregation for the Doctrine of the Faith (CDF), Donum Vitae is intended as a magisterial teaching document that invites further reflection on the relationship between natural moral law and reproductive technologies such as in vitro fertilization. To aid it in its work, the CDF consulted anonymous religious and lay experts in the fields of moral theology, genetics, biology, medicine, and physiology. Harvey speculates on the history of Donum Vitae's preparation, particularly as to the identities of the individuals whom the CDF consulted. He raises the possibility of a biased consultation process, one that called upon moral theologians whose views would be known to support pre-established conclusions.

  15. Reasons on the similarity of objections with regards to gambling and speculation in Islamic finance and conventional finance.

    Science.gov (United States)

    Kunhibava, Sherin

    2011-03-01

    Gambling and speculation which leads to zero-sum outcomes are prohibited in Islamic finance and condemned in conventional finance. This article explores the reasons for the similarity of objections towards gambling and speculation. Three probable reasons are explored namely the concept of stewardship in conventional thought and the concept of khalifa in Islam, Christianity and morality's influence on conventional law and finance and the concept of ethics of sacrifice and ethics of tolerance.

  16. Are familial factors underlying the association between socioeconomic position and prescription medicine?

    DEFF Research Database (Denmark)

    Madsen, Mia; Andersen, Per Kragh; Gerster, Mette

    2013-01-01

    OBJECTIVES: Although well established, the association between socioeconomic position and health and health behaviour is not clearly understood, and it has been speculated that familial factors, for example, dispositional factors or exposures in the rearing environment, may be underlying the asso......OBJECTIVES: Although well established, the association between socioeconomic position and health and health behaviour is not clearly understood, and it has been speculated that familial factors, for example, dispositional factors or exposures in the rearing environment, may be underlying...... and the Danish Registry of Medicinal Product statistics. A total of 8582 monozygotic (MZ) and 15 788 dizygotic same sex (DZSS) twins were included. OUTCOME MEASURES: Number of prescription fillings during follow-up (1995-2005) was analysed according to education and income. Results of unpaired and intrapair...

  17. Defending against speculative attacks: A hybrid model of exchange market pressure and crises

    NARCIS (Netherlands)

    Daniels, T.R.; Jager, H.; Klaassen, F.

    2008-01-01

    While virtually all currency crisis models recognise that the fate of a currency peg depends on how tenaciously policy makers defend it, they seldom model how this is done. We incorporate themechanics of speculation and the interest rate defence against it in the model of Morris and Shin (American

  18. Quantization of dissipative systems - some irresponsible speculations

    International Nuclear Information System (INIS)

    Kochan, Denis

    2007-01-01

    The Newton-Lagrange equations of motion represent the fundamental law of mechanics. Their traditional Lagrangian and/or Hamiltonian precursors when available are essential in the context of quantization. However, there are situations that lack Lagrangian and/or Hamiltonian settings. This paper discusses classical and quantal dynamics of such systems and presents some irresponsible speculations by introducing a certain canonical two-form Ω. By its construction Ω embodies kinetic energy and forces acting within the system (not their potential). A new type of variational principle is introduced, where variation is performed over a set of 'umbilical surfaces' instead of system histories. It provides correct Newton-Lagrange equations of motion and something more. The quantization is inspired by the Feynman functional integral approach. The quintessence is to rearrange path integral into an ''umbilical world-sheet'' integral in accordance with the proposed variational principle. In the case of potential-generated forces, the new approach reduces to the standard quantum mechanics

  19. Evict on write, a management strategy for a prefetch unit and/or first level cache in a multiprocessor system with speculative execution

    Science.gov (United States)

    Gara, Alan; Ohmacht, Martin

    2014-09-16

    In a multiprocessor system with at least two levels of cache, a speculative thread may run on a core processor in parallel with other threads. When the thread seeks to do a write to main memory, this access is to be written through the first level cache to the second level cache. After the write though, the corresponding line is deleted from the first level cache and/or prefetch unit, so that any further accesses to the same location in main memory have to be retrieved from the second level cache. The second level cache keeps track of multiple versions of data, where more than one speculative thread is running in parallel, while the first level cache does not have any of the versions during speculation. A switch allows choosing between modes of operation of a speculation blind first level cache.

  20. Extreme Physics and Informational/Computational Limits

    Energy Technology Data Exchange (ETDEWEB)

    Di Sia, Paolo, E-mail: paolo.disia@univr.it, E-mail: 10alla33@virgilio.it [Department of Computer Science, Faculty of Science, Verona University, Strada Le Grazie 15, I-37134 Verona (Italy) and Faculty of Computer Science, Free University of Bozen, Piazza Domenicani 3, I-39100 Bozen-Bolzano (Italy)

    2011-07-08

    A sector of the current theoretical physics, even called 'extreme physics', deals with topics concerning superstring theories, multiverse, quantum teleportation, negative energy, and more, that only few years ago were considered scientific imaginations or purely speculative physics. Present experimental lines of evidence and implications of cosmological observations seem on the contrary support such theories. These new physical developments lead to informational limits, as the quantity of information, that a physical system can record, and computational limits, resulting from considerations regarding black holes and space-time fluctuations. In this paper I consider important limits for information and computation resulting in particular from string theories and its foundations.

  1. Extreme Physics and Informational/Computational Limits

    International Nuclear Information System (INIS)

    Di Sia, Paolo

    2011-01-01

    A sector of the current theoretical physics, even called 'extreme physics', deals with topics concerning superstring theories, multiverse, quantum teleportation, negative energy, and more, that only few years ago were considered scientific imaginations or purely speculative physics. Present experimental lines of evidence and implications of cosmological observations seem on the contrary support such theories. These new physical developments lead to informational limits, as the quantity of information, that a physical system can record, and computational limits, resulting from considerations regarding black holes and space-time fluctuations. In this paper I consider important limits for information and computation resulting in particular from string theories and its foundations.

  2. Sport physiology, dopamine and nitric oxide - Some speculations and hypothesis generation.

    Science.gov (United States)

    Landers, J G; Esch, Tobias

    2015-12-01

    Elite Spanish professional soccer players surprisingly showed a preponderance of an allele coding for nitric oxide synthase (NOS) that resulted in lower nitric oxide (NO) compared with Spanish endurance and power athletes and sedentary men. The present paper attempts a speculative explanation. Soccer is an "externally-paced" (EP) sport and team work dependent, requiring "executive function skills". We accept that time interval estimation skill is, in part, also an executive skill. Dopamine (DA) is prominent among the neurotransmitters with a role in such skills. Polymorphisms affecting dopamine (especially DRD2/ANKK1-Taq1a which leads to lower density of dopamine D2 receptors in the striatum, leading to increased striatal dopamine synthesis) and COMT val 158 met (which prolongs the action of dopamine in the cortex) feature both in the time interval estimation and the executive skills literatures. Our paper may be a pioneering attempt to stimulate empirical efforts to show how genotypes among soccer players may be connected via neurotransmitters to certain cognitive abilities that predict sporting success, perhaps also in some other externally-paced team sports. Graphing DA levels against time interval estimation accuracy and also against certain executive skills reveals an inverted-U relationship. A pathway from DA, via endogenous morphine and mu3 receptors on endothelia, to the generation of NO in tiny quantities has been demonstrated. Exercise up-regulates DA and this pathway. With somewhat excessive exercise, negative feedback from NO down-regulates DA, hypothetically keeping it near the peak of the inverted-U. Other research, not yet done on higher animals or humans, shows NO "fine-tuning" movement. We speculate that Caucasian men, playing soccer recreationally, would exemplify the above pattern and their nitric oxide synthase (NOS) would reflect the norm of their community, whereas professional players of soccer and perhaps other EP sports, with DA boosted by

  3. The Iron Law of Financial Markets: Self-fulfilling Prophecies and Speculative Booms and Busts

    Directory of Open Access Journals (Sweden)

    Ognjen Radonjić

    2016-02-01

    Full Text Available This paper discusses the factors which, in the absence of strong financial regulation, sustain the Iron Law of the Financial Markets asserting that speculative booms and busts occur more or less regularly from 17 century to the present. The first factor is that financial markets are self-fulfilling system. The second is that human nature does not change and is based on egoism, materialism, loss aversion, exaggerated hopes and fears, emulation, propensity to gamble, herd behavior and so on. Lastly, there is the extreme brevity of the financial memory. In order to enable economic authorities and/or individuals to detect timely that the unsustainable boom is under the way, we have identified the common features of historically recorded speculative episodes. Stages through which the system passes on its way from unsustainable rise to inevitable fall are: displacement, boom, overtrading, financial distress and discredit or revulsion.

  4. The Effect of Founder Family Influence on Hedging and Speculation

    DEFF Research Database (Denmark)

    Aabo, Tom; Kuhn, Jochen; Zanotti, Giovanna

    We investigate the effect of founder family influence in the form of managers, board of directors, and/or ownership on hedging and speculation in medium-sized, manufacturing firms in Denmark. On a crude measure of use / non-use of derivatives we find only a weak indication of differences between...... founder family firms and other firms in relation to their management of foreign exchange rate, interest rate, and commodity price exposures. Digging deeper into a subsample of users of foreign exchange derivatives and debt denominated in foreign currency, we find that founder family firms not only tend...

  5. Liquidity Risk, Speculative Trade, and the Optimal Latency of Financial Markets

    OpenAIRE

    Fricke, Daniel; Gerig, Austin

    2014-01-01

    Garbade and Silber (1979) demonstrate that an asset will be liquid if it has (1) low price volatility and (2) a large number of public investors who trade it. Although these results match nicely with common notions of liquidity, one key element is missing: liquidity also depends on (3) an asset s correlation with other securities. For example, if an illiquid asset is highly correlated with a liquid asset, then speculators will naturally step in and make it liquid . In this paper, we update Ga...

  6. Speculative Bubbles and Financial Crises: A Neo-functionalist Approach

    Directory of Open Access Journals (Sweden)

    José María García Blanco

    2015-01-01

    Full Text Available If economics tends to emphasize the role of irrational behaviour in the formation of the speculative bubble that caused the recent financial crisis, sociology tends to focus on the institutions and social structures that sustain the financial system, particularly the dense social networks formed by financial elites, which function as a socio-culturally closed circle leading to herd behaviour. This article proposes a different interpretation of this supposed herd behaviour, based on functional differentiation and how it fosters internal, second order observation. Modern markets are a particularly striking example of this, and especially financial ones in which self-referential closure is particularly intense, because they trade money, the medium that supports the self-reference of the economic system.

  7. Two Fundamental Problems and Two Periods of German Speculative Idealism

    Directory of Open Access Journals (Sweden)

    V. ZOLOTUKHIN

    2015-02-01

    Full Text Available The author’s concerns are with the philosophical and theological problems integral to German Speculative Idealism. Two key ideas permeated the whole of German Idealism: the idea of divine self-realization / self-understanding and the idea of gravitating between the poles of theism and pantheism. The author attempts to explain how these two ideas are related throughout the course of German Idealism. He includes in this study not only Fichte /the elder/, Schelling, and Hegel, but also the so-called speculative theists (Fichte /the younger/ and others, whose thought in both ideology and methodology resembles that of Schelling and Hegel. The author demonstrates using the writings of the philosophers that the two ideas may be related though the concept of creativity . If God realizes himself in the world and through the world, then it makes sense to say that philosophical theology is replete with pantheism. But if the divine realization takes place ontologically before the process of creation and is in itself an act which takes place within the divine Being Himself, the process is then clearly theistic. Idealists of the older school do not link creation with the Absolute - they reject this point or they speak about creation in reference to the act of divine self-realization. Idealists of the younger generation, on the contrary, hold that the act of divine self-realization precedes that of creation. The author opines that it is this point which allows us to diff erentiate between a philosophical system which leans towards pantheism from one which tends toward theism. The older idealists were indeed mostly pantheists, while the younger generation was mostly theistic. In view of this, German Idealism may be considered to be divided into two periods

  8. Radio-frequency electromagnetic field (RF-EMF) exposure levels in different European outdoor urban environments in comparison with regulatory limits

    NARCIS (Netherlands)

    Urbinello, Damiano; Joseph, Wout; Huss, Anke|info:eu-repo/dai/nl/331385880; Verloock, Leen; Beekhuizen, Johan|info:eu-repo/dai/nl/34472641X; Vermeulen, Roel|info:eu-repo/dai/nl/216532620; Martens, Luc; Röösli, Martin

    Background: Concerns of the general public about potential adverse health effects caused by radio-frequency electromagnetic fields (RF-EMFs) led authorities to introduce precautionary exposure limits, which vary considerably between regions. It may be speculated that precautionary limits affect the

  9. Discrete geometry: speculations on a new framework for classical electrodynamics

    International Nuclear Information System (INIS)

    Hemion, G.

    1988-01-01

    An attempt is made to describe the basic principles of physics in terms of discrete partially ordered sets. Geometric ideas are introduced by means of an action at a distance formulation of classical electrodynamics. The speculations are in two main directions: (i) Gravity, one of the four elementary forces of nature, seems to be fundamentally different from the other three forces. Could it be that gravity can be explained as a natural consequence of the discrete structure? (ii) The problem of the observer in quantum mechanics continues to cause conceptual problems. Can quantum statistics be explained in terms of finite ensembles of possible partially ordered sets? The development is guided at all stages by reference to the simplest, and most well-established principles of physics

  10. Benign paroxysmal positional vertigo after use of noise-canceling headphones.

    Science.gov (United States)

    Dan-Goor, Eric; Samra, Monica

    2012-01-01

    Benign paroxysmal positional vertigo (BPPV) is a common cause of vertigo. We describe a case of a woman presenting acutely with a severe episode of disabling positional vertigo. Although she had no known etiologic risk factors, this attack followed 12 hours of continuously wearing digital noise-canceling headphones. This is the first such reported association between BPPV and the use of this gadget. We also provide a short review of BPPV and speculate on the possible pathogenic mechanisms involved. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Volume Shocks around Announcements in the Chinese Stock Market: An Ex-Post Earnings-Information-Based Study of Speculative Behavior

    Directory of Open Access Journals (Sweden)

    Xiangdong Chen

    2017-09-01

    Full Text Available The Second Board Market is typical stock market for high tech companies in China. This paper discusses the relationship between trading volume and price changes in the case of high-tech listed companies in the Chinese Second-Board Stock Market. By using the basic concepts proposed by Kim and Verrecchia, and Kandel and Pearson, and contrasting them with ex-post information from earnings releases, the paper provides findings on the speculative behavior of informed traders with a volume shock premium. The paper suggests that these methods may be further applied to investigating investors’ behavior in speculation, especially for the high-tech-company-based Second-Board Stock Market during announcement periods.

  12. Physical Limits on the Precision of Mitotic Spindle Positioning by Microtubule Pushing forces: Mechanics of mitotic spindle positioning.

    Science.gov (United States)

    Howard, Jonathon; Garzon-Coral, Carlos

    2017-11-01

    Tissues are shaped and patterned by mechanical and chemical processes. A key mechanical process is the positioning of the mitotic spindle, which determines the size and location of the daughter cells within the tissue. Recent force and position-fluctuation measurements indicate that pushing forces, mediated by the polymerization of astral microtubules against- the cell cortex, maintain the mitotic spindle at the cell center in Caenorhabditis elegans embryos. The magnitude of the centering forces suggests that the physical limit on the accuracy and precision of this centering mechanism is determined by the number of pushing microtubules rather than by thermally driven fluctuations. In cells that divide asymmetrically, anti-centering, pulling forces generated by cortically located dyneins, in conjunction with microtubule depolymerization, oppose the pushing forces to drive spindle displacements away from the center. Thus, a balance of centering pushing forces and anti-centering pulling forces localize the mitotic spindles within dividing C. elegans cells. © 2017 The Authors. BioEssays published by Wiley Periodicals, Inc.

  13. tDCS for Memory Enhancement: Analysis of the Speculative Aspects of Ethical Issues.

    Science.gov (United States)

    Voarino, Nathalie; Dubljević, Veljko; Racine, Eric

    2016-01-01

    Transcranial direct current stimulation (tDCS) is a promising technology to enhance cognitive and physical performance. One of the major areas of interest is the enhancement of memory function in healthy individuals. The early arrival of tDCS on the market for lifestyle uses and cognitive enhancement purposes lead to the voicing of some important ethical concerns, especially because, to date, there are no official guidelines or evaluation procedures to tackle these issues. The aim of this article is to review ethical issues related to uses of tDCS for memory enhancement found in the ethics and neuroscience literature and to evaluate how realistic and scientifically well-founded these concerns are? In order to evaluate how plausible or speculative each issue is, we applied the methodological framework described by Racine et al. (2014) for "informed and reflective" speculation in bioethics. This framework could be succinctly presented as requiring: (1) the explicit acknowledgment of factual assumptions and identification of the value attributed to them; (2) the validation of these assumptions with interdisciplinary literature; and (3) the adoption of a broad perspective to support more comprehensive reflection on normative issues. We identified four major considerations associated with the development of tDCS for memory enhancement: safety, autonomy, justice and authenticity. In order to assess the seriousness and likelihood of harm related to each of these concerns, we analyzed the assumptions underlying the ethical issues, and the level of evidence for each of them. We identified seven distinct assumptions: prevalence, social acceptance, efficacy, ideological stance (bioconservative vs. libertarian), potential for misuse, long term side effects, and the delivery of complete and clear information. We conclude that ethical discussion about memory enhancement via tDCS sometimes involves undue speculation, and closer attention to scientific and social facts would bring

  14. Speculations on the initiation of chromosome replication in Escherichia coli: the dualism hypothesis.

    Science.gov (United States)

    Norris, Vic

    2011-05-01

    The exact nature of the mechanism that triggers initiation of chromosome replication in the best understood of all organisms, Escherichia coli, remains mysterious. Here, I suggest that this mechanism evolved in response to the problems that arise if chromosome replication does not occur. E. coli is now known to be highly structured. This leads me to propose a mechanism for initiation of replication based on the dynamics of large assemblies of molecules and macromolecules termed hyperstructures. In this proposal, hyperstructures and their constituents are put into two classes, non-equilibrium and equilibrium, that spontaneously separate and that are appropriate for life in either good or bad conditions. Maintaining the right ratio(s) of non-equilibrium to equilibrium hyperstructures is therefore a major challenge for cells. I propose that this maintenance entails a major transfer of material from equilibrium to non-equilibrium hyperstructures once per cell and I further propose that this transfer times the cell cycle. More specifically, I speculate that the dialogue between hyperstructures involves the structuring of water and the condensation of cations and that one of the outcomes of ion condensation on ribosomal hyperstructures and decondensation from the origin hyperstructure is the separation of strands at oriC responsible for triggering initiation of replication. The dualism hypothesis that comes out of these speculations may help integrate models for initiation of replication, chromosome segregation and cell division with the 'prebiotic ecology' scenario of the origins of life. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. From hero to zero: Evidence of performance reversal and speculative bubbles in German renewable energy stocks

    International Nuclear Information System (INIS)

    Bohl, Martin T.; Kaufmann, Philipp; Stephan, Patrick M.

    2013-01-01

    Stocks of German renewable energy companies have commonly been regarded as lucrative investment opportunities. Their innovative line of business initially seemed to promise considerable future earnings. As shown by two powerful bubble tests, the positive sentiment for renewable energy stocks even led to explosive price behavior in the mid-2000s. However, intense sector competition and the economic downturn following the global financial crisis erased profit margins to a large extent. As a result, the former fad stocks have recently turned into losers, loading negatively on price momentum and delivering significantly negative Carhart four-factor alphas. The radical shift in Germany's energy policy following the 2011 Fukushima nuclear disaster in Japan could thus only temporarily halt the continuing decline in alternative energy stock prices. - Highlights: ► We examine the return behavior of German renewable energy stocks between 2004 and 2011. ► The former fad stocks have recently turned into loser stocks. ► They produced significantly negative Carhart four-factor alphas since 2008. ► The price behavior before 2008 was considerably driven by explosiveness. ► Upbeat sector sentiment in the mid-2000s might have caused this speculative bubble

  16. A size upper limit and position for the HCN maser in CIT 6

    International Nuclear Information System (INIS)

    Carlstrom, J.E.; Welch, W.J.; Goldsmith, P.F.; Lis, D.C.

    1990-01-01

    A size upper limit and position for the HCN maser in CIT 6 were determined from interferometric observations with the Hat Creek millimeter array. The maser is located at alpha(1950) = 10 h 13 m 10.942 + or - 0.012 s and delta(1950) = + 30 deg 49 arcmin 16.75 arcsec + or - 0.15, coincident with the optical image taken from the Palomar plates, within the 3 arcsec uncertainty of the latter. The size of the maser emission region is less than 0.45 arcsec, approximately 180 AU at the distance estimated for CIT 6. The small size and strong emission (40 Jy) set a lower limit to the brightness temperature of 44,000 K, further strengthening the maser interpretation. 14 refs

  17. Speculative resources of uranium. A review of International Uranium Resources Evaluation Project (IUREP) estimates 1982-1983

    International Nuclear Information System (INIS)

    1983-01-01

    On a country by country basis the International Uranium Resources Evaluation Project (IUREP) estimates 1982-1983 are reviewed. Information provided includes exploration work, airborne survey, radiometric survey, gamma-ray spectrometric survey, estimate of speculative resources, uranium occurrences, uranium deposits, uranium mineralization, agreements for uranium exploration, feasibilities studies, geological classification of resources, proposed revised resource range, production estimate of uranium

  18. Thinking about a limited future enhances the positivity of younger and older adults' recall: Support for socioemotional selectivity theory.

    Science.gov (United States)

    Barber, Sarah J; Opitz, Philipp C; Martins, Bruna; Sakaki, Michiko; Mather, Mara

    2016-08-01

    Compared with younger adults, older adults have a relative preference to attend to and remember positive over negative information. This is known as the "positivity effect," and researchers have typically evoked socioemotional selectivity theory to explain it. According to socioemotional selectivity theory, as people get older they begin to perceive their time left in life as more limited. These reduced time horizons prompt older adults to prioritize achieving emotional gratification and thus exhibit increased positivity in attention and recall. Although this is the most commonly cited explanation of the positivity effect, there is currently a lack of clear experimental evidence demonstrating a link between time horizons and positivity. The goal of the current research was to address this issue. In two separate experiments, we asked participants to complete a writing activity, which directed them to think of time as being either limited or expansive (Experiments 1 and 2) or did not orient them to think about time in a particular manner (Experiment 2). Participants were then shown a series of emotional pictures, which they subsequently tried to recall. Results from both studies showed that regardless of chronological age, thinking about a limited future enhanced the relative positivity of participants' recall. Furthermore, the results of Experiment 2 showed that this effect was not driven by changes in mood. Thus, the fact that older adults' recall is typically more positive than younger adults' recall may index naturally shifting time horizons and goals with age.

  19. Thinking about a Limited Future Enhances the Positivity of Younger and Older Adults’ Recall: Support for Socioemotional Selectivity Theory

    Science.gov (United States)

    Barber, Sarah J.; Opitz, Philipp C.; Martins, Bruna; Sakaki, Michiko; Mather, Mara

    2016-01-01

    Compared with younger adults, older adults have a relative preference to attend to and remember positive over negative information. This is known as the “positivity effect,” and researchers have typically evoked socioemotional selectivity theory to explain it. According to socioemotional selectivity theory, as people get older they begin to perceive their time left in life as more limited. These reduced time horizons prompt older adults to prioritize achieving emotional gratification and thus exhibit increased positivity in attention and recall. Although this is the most commonly cited explanation of the positivity effect, there is currently a lack of clear experimental evidence demonstrating a link between time horizons and positivity. The goal of the current research was to address this issue. In two separate experiments, we asked participants to complete a writing activity, which directed them to think of time as being either limited or expansive (Experiments 1 and 2) or did not orient them to think about time in a particular manner (Experiment 2). Participants were then shown a series of emotional pictures, which they subsequently tried to recall. Results from both studies showed that regardless of chronological age, thinking about a limited future enhanced the relative positivity of participants’ recall. Furthermore, the results of Experiment 2 showed that this effect was not driven by changes in mood. Thus, the fact that older adults’ recall is typically more positive than younger adults’ recall may index naturally shifting time horizons and goals with age. PMID:27112461

  20. Transuranium element toxicity: dose-response relationships at low exposure levels. Summary and speculative interpretation relative to exposure limits

    International Nuclear Information System (INIS)

    Thompson, R.C.

    1975-01-01

    A summary is given of information on transuranium element toxicity and the correlation of this information with current established exposure limits. It is difficult to calculate a biologically relevant radiation dose from deposited plutonium; it is exposure that must be controlled in order to prevent biological effect, and if the relationship between exposure and effect is known, then radiation dose is of no concern. There are extensive data on the effects of plutonium in bone. Results of studies at the University of Utah indicate that plutonium in beagles may be as much as ten times more toxic than radium. It has been suggested that this toxicity ratio may be even higher in man than in the beagle dog because of differences in surface-to-volume ratios and differences in the rate of burial of surface-deposited plutonium. The present capabilities for extrapolating dose-effect relationships seem to be limited to the setting of upper limits, based on assumptions of linearity and considerations related to natural background

  1. Interference and memory capacity limitations.

    Science.gov (United States)

    Endress, Ansgar D; Szabó, Szilárd

    2017-10-01

    Working memory (WM) is thought to have a fixed and limited capacity. However, the origins of these capacity limitations are debated, and generally attributed to active, attentional processes. Here, we show that the existence of interference among items in memory mathematically guarantees fixed and limited capacity limits under very general conditions, irrespective of any processing assumptions. Assuming that interference (a) increases with the number of interfering items and (b) brings memory performance to chance levels for large numbers of interfering items, capacity limits are a simple function of the relative influence of memorization and interference. In contrast, we show that time-based memory limitations do not lead to fixed memory capacity limitations that are independent of the timing properties of an experiment. We show that interference can mimic both slot-like and continuous resource-like memory limitations, suggesting that these types of memory performance might not be as different as commonly believed. We speculate that slot-like WM limitations might arise from crowding-like phenomena in memory when participants have to retrieve items. Further, based on earlier research on parallel attention and enumeration, we suggest that crowding-like phenomena might be a common reason for the 3 major cognitive capacity limitations. As suggested by Miller (1956) and Cowan (2001), these capacity limitations might arise because of a common reason, even though they likely rely on distinct processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Mad Speculation and Absolute Inhumanism: Lovecraft, Ligotti, and the Weirding of Philosophy

    Directory of Open Access Journals (Sweden)

    Ben Woodard

    2011-03-01

    Full Text Available I want to propose, as a trajectory into the philosophically weird, an absurd theoretical claim and pursue it, or perhaps more accurately, construct it as I point to it, collecting the ground work behind me like the Perpetual Train from China Mieville's Iron Council which puts down track as it moves reclaiming it along the way. The strange trajectory is the following: Kant's critical philosophy and much of continental philosophy which has followed, has been a defense against horror and madness. Kant's prohibition on speculative metaphysics such as dogmatic metaphysics and transcendental realism, on thinking beyond the imposition of transcendental and moral constraints, has been challenged by numerous figures proceeding him.

  3. The analysis of return on speculative trading with futures contracts of agriculture commodities in the context of the currency risk

    Directory of Open Access Journals (Sweden)

    Oldřich Šoba

    2007-01-01

    Full Text Available The paper is focused on analysis of return on speculative operations with futures contracts from the view of participators not undertaking and undertaking the currency risk. The currency risk is determined by unexpected change of relevant exchange rate (currency denomination of futures contracts / domestic currency of participator. The paper analyses the basic factors influencing the profitability of these operations such as relative change of futures contract value, leverage incidence and relative change of relevant exchange rate. The paper is focused on futures contracts of the world most important agricultural commodities. The conclusion of the paper for participators not undertaking the currency risk is following: The relative change of futures contract is main factor for the calculation of return on speculative operation. This change is multiplied by leverage incidence finally. The conclusion of the paper for participators undertaking the currency risk is following: The relative change of relevant exchange rate is not usually relevant for the calculation of return on speculative operation. Main factor is the relative change of futures contract because this change is multiplied by leverage incidence finally but the relative change of relevant exchange rate isn’t.Neverthless the conclusions of this paper are not valid only for futures contracts of agricultural commodities but generally also for other commodity futures contracts and futures contracts where underlying assets are not commodities but for example financial assets.

  4. A speculated ribozyme site in the herpes simplex virus type 1 latency-associated transcript gene is not essential for a wild-type reactivation phenotype

    Science.gov (United States)

    Carpenter, Dale; Singh, Sukhpreet; Osorio, Nelson; Hsiang, Chinhui; Jiang, Xianzhi; Jin, Ling; Jones, Clinton; Wechsler, Steven L

    2010-01-01

    During herpes simplex virus-1 (HSV-1) latency in sensory neurons, LAT (latency-associated transcript) is the only abundantly expressed viral gene. LAT plays an important role in the HSV-1 latency-reactivation cycle, because LAT deletion mutants have a significantly decreased reactivation phenotype. Based solely on sequence analysis, it was speculated that LAT encodes a ribozyme that plays an important role in how LAT enhances the virus’ reactivation phenotype. Because LAT ribozyme activity has never been reported, we decided to test the converse hypothesis, namely, that this region of LAT does not encode a ribozyme function important for LAT’s ability to enhance the reactivation phenotype. We constructed a viral mutant (LAT-Rz) in which the speculated ribozyme consensus sequence was altered such that no ribozyme was encoded. We report here that LAT-Rz had a wild-type reactivation phenotype in mice, confirming the hypothesis that the speculated LAT ribozyme is not a dominant factor in stimulating the latency-reactivation cycle in mice. PMID:18982533

  5. MDEP Common Position CP-DICWG-07. Common position on selection and use of industrial digital devices of limited functionality

    International Nuclear Information System (INIS)

    2014-01-01

    The nuclear power industry is increasingly interested in using industrial digital devices of limited functionality in systems important to safety, but that have not been developed specifically for use in nuclear power applications. These devices should meet certain specific requirements in order to be selected and used in systems important to safety at nuclear power plants. Typically, some of these devices are found embedded in plant components and actuating devices, e.g. sensing instrumentation, motors, pumps, actuators, breakers. The Digital Instrumentation and Controls Working Group (DICWG) has agreed that a common position on this topic is warranted given the increase of use of Digital I and C in new reactor designs, its safety implications, and the need to develop a common understanding from the perspectives of regulatory authorities. This action follows the DICWG examination of the regulatory requirements of the participating members and of relevant industry standards and IAEA documents. The DICWG proposes a common position based on its recent experience with the new reactor application reviews and operating plant issues

  6. The searched freedom: last philosophical speculation of Luigi Pareyson. (1975-1991

    Directory of Open Access Journals (Sweden)

    Íris Fátima da Silva Uribe

    2012-10-01

    Full Text Available The presented theme is developed in the volume Ontologia della libertà. Il male e la sofferenza, in which Luigi Pareyson deeply rethink the problem of liberty, articulated through a decisive confrontation, whose ontological and hermeneutic root, puts itself in relation with the Hebrew-Christian “myth”. However, is inside the person’s experience crystallized in human existence that occurs the confrontation between philosophy and religion presented on the already alluded volume. Nevertheless, the sought for freedom is the reveling speculation of Pareyson’s effort to respond to evil and suffering experience that signs the human existence; it is, in fact, the trodden search since the first investigations about the existence philosophy as crisis philosophy, in our time, in which inserts the person’s singularity in its historical concreteness, both in fullness and variety of its manifestations

  7. Efficiency or speculation? A time-varying analysis of European sovereign debt

    Science.gov (United States)

    Ferreira, Paulo

    2018-01-01

    The outbreak of the Greek debt crisis caused turmoil in European markets and drew attention to the problem of public debt and its consequences. The increase in the return rates of sovereign debts was one of these consequences. However, like any other asset, sovereign debt returns are expected to have a memoryless behaviour. Analysing a total of 15 European countries (Eurozone and non-Eurozone), and applying a time-varying analysis of the Hurst exponent, we found evidence of long-range memory in sovereign bonds. When analysing the spreads between each bond and the German one, it is possible to conclude that Eurozone countries' spreads show more evidence of long-range dependence. Considering the Eurozone countries most affected by the Eurozone crisis, that long-range dependence is more evident, but started before the crisis, which could be interpreted as possible speculation by investors.

  8. The limits of direct satellite tracking with the Global Positioning System (GPS)

    Science.gov (United States)

    Bertiger, W. I.; Yunck, T. P.

    1988-01-01

    Recent advances in high precision differential Global Positioning System-based satellite tracking can be applied to the more conventional direct tracking of low earth satellites. To properly evaluate the limiting accuracy of direct GPS-based tracking, it is necessary to account for the correlations between the a-priori errors in GPS states, Y-bias, and solar pressure parameters. These can be obtained by careful analysis of the GPS orbit determination process. The analysis indicates that sub-meter accuracy can be readily achieved for a user above 1000 km altitude, even when the user solution is obtained with data taken 12 hours after the data used in the GPS orbit solutions.

  9. Past speculations of the future: a review of the methods used for forecasting emerging health technologies.

    Science.gov (United States)

    Doos, Lucy; Packer, Claire; Ward, Derek; Simpson, Sue; Stevens, Andrew

    2016-03-10

    Forecasting can support rational decision-making around the introduction and use of emerging health technologies and prevent investment in technologies that have limited long-term potential. However, forecasting methods need to be credible. We performed a systematic search to identify the methods used in forecasting studies to predict future health technologies within a 3-20-year timeframe. Identification and retrospective assessment of such methods potentially offer a route to more reliable prediction. Systematic search of the literature to identify studies reported on methods of forecasting in healthcare. People are not needed in this study. The authors searched MEDLINE, EMBASE, PsychINFO and grey literature sources, and included articles published in English that reported their methods and a list of identified technologies. Studies reporting methods used to predict future health technologies within a 3-20-year timeframe with an identified list of individual healthcare technologies. Commercially sponsored reviews, long-term futurology studies (with over 20-year timeframes) and speculative editorials were excluded. 15 studies met our inclusion criteria. Our results showed that the majority of studies (13/15) consulted experts either alone or in combination with other methods such as literature searching. Only 2 studies used more complex forecasting tools such as scenario building. The methodological fundamentals of formal 3-20-year prediction are consistent but vary in details. Further research needs to be conducted to ascertain if the predictions made were accurate and whether accuracy varies by the methods used or by the types of technologies identified. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. Handgrip Strength, Positive Affect, and Perceived Health Are Prospectively Associated with Fewer Functional Limitations among Centenarians

    Science.gov (United States)

    Franke, Warren D.; Margrett, Jennifer A.; Heinz, Melinda; Martin, Peter

    2012-01-01

    This study assessed the association between perceived health, fatigue, positive and negative affect, handgrip strength, objectively measured physical activity, body mass index, and self-reported functional limitations, assessed 6 months later, among 11 centenarians (age = 102 plus or minus 1). Activities of daily living, assessed 6 months prior to…

  11. Low Upper Limit to Methane Abundance on Mars

    Science.gov (United States)

    Webster, Christopher R.; Mahaffy, Paul R.; Atreya, Sushil K.; Flesch, Gregory J.; Farley, Kenneth A.; Kemppinen, Osku; Bridges, Nathan; Johnson, Jeffrey R.; Minitti, Michelle; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Weigle, Gerald; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Grotzinger, John; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Elvira, Javier Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Soler, Javier Martín; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; DeMarines, Julia; Grinspoon, David; Reitz, Günther; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Eigenbrode, Jennifer; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Posner, Arik; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Brinza, David; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Vasavada, Ashwin R.; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Cucinotta, Francis; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Bullock, Mark; Ehresmann, Bent; Hamilton, Victoria; Hassler, Donald; Peterson, Joseph; Rafkin, Scot; Zeitlin, Cary; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Kim, Myung-Hee; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; Boehm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; García, César Martín; Mueller-Mellin, Reinhold; Wimmer-Schweingruber, Robert; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

    2013-10-01

    By analogy with Earth, methane in the Martian atmosphere is a potential signature of ongoing or past biological activity. During the past decade, Earth-based telescopic observations reported “plumes” of methane of tens of parts per billion by volume (ppbv), and those from Mars orbit showed localized patches, prompting speculation of sources from subsurface bacteria or nonbiological sources. From in situ measurements made with the Tunable Laser Spectrometer (TLS) on Curiosity using a distinctive spectral pattern specific to methane, we report no detection of atmospheric methane with a measured value of 0.18 ± 0.67 ppbv corresponding to an upper limit of only 1.3 ppbv (95% confidence level), which reduces the probability of current methanogenic microbial activity on Mars and limits the recent contribution from extraplanetary and geologic sources.

  12. Design and construction of the movable limiters for holding the plasma in position in the nuclear fusion experiment TEXTOR

    International Nuclear Information System (INIS)

    Butzek, D.A.; Derichs, K.

    1983-11-01

    The nuclear fusion experiment TEXTOR (Tokamak Experiment for Technology Oriented Research) has been constructed for investigation of plasma-wall-interaction. The plasma is generated inside a torus-shaped vacuum vessel. In addition to the magnetic fields mechanical limiters are provided to hold the plasma in position. The limiter scheme of textor consists of main limiters and reference limiters (measuring limiters). Main and reference limiters are mounted in different cross sections of the torus. The main limiters are movable during the plasma discharge while the reference limiters are kept fixed. They are adjustable. Thus, by moving the main limiters, the reference limiters can be exposed to different thermal loads during the discharge. Exposing the reference limiters to the plasma, first results have been obtained concerning the scrape off layer: thickness, fluxes of hydrogen and chromium through this layer. The limiter scheme, the final design and construction of the limiters and the first phase of operation are described in this report. (orig.) [de

  13. Survey of beam-beam limitations

    International Nuclear Information System (INIS)

    Courant, E.; Cornacchia, M.; Donald, M.M.R.; Evans, L.R.; Tazzari, S.; Wilson, E.J.N.

    1979-01-01

    The effect of beam-beam interaction is known to limit the luminosity of electron-positron storage rings and will, no doubt, limit the proton-antiproton collision scheme for the SPS. While theorists are struggling to explain this phenomenon it is more instructive to list their failures than their rather limited successes, in the hope that experiments may emerge which will direct their endeavors. The search for a description of a nonlinear system as it approaches the limit in which ordered motion breaks down, is the nub of the problem. It has engaged many fine mathematical intellects for decades and will no doubt continue to do so long after ISABELLE, the p antip and LEP are past achievements. Empirical scaling laws are emerging which relate electron machines to each other but their extrapolation to proton machines remain a very speculative exercise. Experimental data on proton limits is confined to one machine, the ISR, which does not normally suffer the beam-beam effect and where it must be artificially induced or simulated. This machine is also very different in important ways from the p antip collider. The gloomy picture which has emerged recently is that the fixed limits which were conventionally assumed for proton and electron machines can only be said to be valid for the machines which engendered them - the best guess that could be made at the time. They are very difficult to extrapolate to other sets of parameters

  14. Nonlinear expectations in speculative markets – Evidence from the ECB survey of professional forecasters

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Rülke; Reitz

    2012-01-01

    Chartist and fundamentalist models have proven to be capable of replicating stylized facts on speculative markets. In general, this is achieved by specifying nonlinear interactions of otherwise linear asset price expectations of the respective trader groups. This paper investigates whether...... in the neighborhood of the fundamental value, whereas expectations tend to be stabilizing in the presence of substantial oil price misalignment....... or not regressive and extrapolative expectations themselves exhibit significant nonlinear dynamics. The empirical results are based on a new data set from the European Central Bank Survey of Professional Forecasters on oil price expectations. In particular, we find that forecasters form destabilizing expectations...

  15. Some speculations on a causal unification of relativity, gravitation, and quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Buonomano, V; Engel, A [Universidade Estadual de Campinas (Brazil). Instituto de Matematica

    1976-03-01

    Some speculations on a causal model that could provide a common conceptual foundation for relativity, gravitation, and quantum mechanics are presented. The present approach is a unification of three theories, the first being the repulsive theory of gravitational forces first proposed by Lesage who attempted to explain gravitational forces from the principle of conservation of momentum of the hypothetical particles gravitons. The second of these theories is the Brownian motion theory of quantum mechanics or stochastic mechanics, which treats the nondeterministic nature of quantum mechanics as being due to a Brownian motion of all objects. This Brownian motion being caused by the statistical variation in the graviton flux. The above two theories are unified in this article with the causal theory of special relativity. The Big Bang theory of the creation of the Universe is assumed. An experimental test is proposed.

  16. Safety limiting values. Low frequent electromagnetic fields - knowledge, hypotheses, speculations

    International Nuclear Information System (INIS)

    Hosemann, G.

    1993-01-01

    Electric and magnetic fields influence in any way any vegetable, animal or human cells, cell structures, enzymes and control functions not other than temperature, air pressure and humidity. With the present state of knowledge, noxious effects cannot be derived by no means. (orig.) [de

  17. Speculative petroleum systems of the Punta del Este Basin (offshore Uruguay

    Directory of Open Access Journals (Sweden)

    Ethel Morales

    Full Text Available ABSTRACT: The Uruguayan continental margin was generated as the result of the breakup of Gondwana and, later, the opening of the South Atlantic Ocean, which began in the Jurassic. Three major areas of Meso-Cenozoic sedimentation are located in the Uruguayan offshore: the Punta del Este Basin, the southernmost sector of the Pelotas Basin and the Oriental del Plata Basin. These basins share the classical stages of tectono-sedimentary evolution of the other Atlantic basins, including the prerift (Paleozoic, rift (Jurassic-Early Cretaceous, transition (Barremian-Aptian and postrift (Aptian-present phases. Based on the analysis of basin evolution through seismic sections and well data as well as on the establishment of analogies with productive Atlantic basins, four speculative petroleum systems are proposed for the Punta del Este Basin: 1 Marine petroleum system of the prerift stage: Devonian/Permian-Devonian/Permian(?, 2 Lacustrine petroleum system of the synrift stage: Neocomian-Neocomian(?, 3 Marine petroleum system of the Cretaceous postrift: Aptian-Late Cretaceous(?, 4 Marine petroleum system of the Cenozoic postrift: Paleocene-Paleogene/Neogene(?.

  18. Thinking about a Limited Future Enhances the Positivity of Younger and Older Adults’ Recall: Support for Socioemotional Selectivity Theory

    OpenAIRE

    Barber, Sarah J.; Opitz, Philipp C.; Martins, Bruna; Sakaki, Michiko; Mather, Mara

    2016-01-01

    Compared with younger adults, older adults have a relative preference to attend to and remember positive over negative information. This is known as the “positivity effect,” and researchers have typically evoked socioemotional selectivity theory to explain it. According to socioemotional selectivity theory, as people get older they begin to perceive their time left in life as more limited. These reduced time horizons prompt older adults to prioritize achieving emotional gratification and thus...

  19. Limitations on blanket performance

    International Nuclear Information System (INIS)

    Malang, S.

    1999-01-01

    The limitations on the performance of breeding blankets in a fusion power plant are evaluated. The breeding blankets will be key components of a plant and their limitations with regard to power density, thermal efficiency and lifetime could determine to a large degree the attractiveness of a power plant. The performance of two rather well known blanket concepts under development in the frame of the European Blanket Programme is assessed and their limitations are compared with more advanced (and more speculative) concepts. An important issue is the question of which material (structure, breeder, multiplier, coatings) will limit the performance and what improvement would be possible with a 'better' structural material. This evaluation is based on the premise that the performance of the power plant will be limited by the blankets (including first wall) and not by other components, e.g. divertors, or the plasma itself. However, the justness of this premise remains to be seen. It is shown that the different blanket concepts cover a large range of allowable power densities and achievable thermal efficiencies, and it is concluded that there is a high incentive to go for better performance in spite of possibly higher blanket cost. However, such high performance blankets are usually based on materials and technologies not yet developed and there is a rather high risk that the development could fail. Therefore, it is explained that a part of the development effort should be devoted to concepts where the materials and technologies are more or less in hand in order to ensure that blankets for a DEMO reactor can be developed and tested in a given time frame. (orig.)

  20. Speculazione sulle valute e fluttuazzioni del dollaro. (Currency speculation and dollar fluctuations

    Directory of Open Access Journals (Sweden)

    S. SCHULMEISTER

    2013-12-01

    Full Text Available In questo studio i motivi dietro le ampie fluttuazioni del tasso di cambio del dollaro a seguito del crollo del sistema di Bretton Woods, per la maggior parte non spiegata dalle teorie prevalenti del tasso di cambio, sono esplorate. L'autore indaga il tasso di cambio tra le due valute più scambiate, il dollaro e il marco tedesco, dal 1973 al 1988. Nella prima parte, il modello dei movimenti dei tassi di cambio quotidiani viene esaminato per dimostrare che una sequenza di rialzo o al ribasso interrotto da movimenti non direzionali è tipico della dinamica dei tassi di cambio nel breve periodo. Questo modello è sistematicamente sfruttata attraverso speculazione monetaria, in particolare attraverso l'uso di "analisi tecnica". Nella seconda parte, l'autore si concentra sul medio termine, sostenendo che le fluttuazioni possono essere spiegati come il risultato di interagire squilibri dei beni e mercati delle attività. Anche se valuta la speculazione è stata sistematicamente redditizio per la maggior parte delle valute, deve essere considerata destabilizzante in quanto la sequenza delle corse dei prezzi ha causato notevoli e persistenti deviazioni dei tassi di cambio dai loro valori di equilibrio (PIL.In this study the reasons behind the wide fluctuations of the dollar exchange rate following the breakdown of the Bretton Woods system, for the most part unexplained by the prevailing exchange rate theories, are explored. The author investigates the exchange rate between the two most traded currencies, the dollar and the deutschemark, from 1973 to 1988. In the first part, the pattern of the daily exchange rate movements is examined to show that a sequence of upward and downward trends interrupted by non-directional movements is typical of exchange rate dynamics in the short run. This pattern is systemically exploited through currency speculation, particularly through the use of “technical analysis”. In the second part, the author focuses on the

  1. Recall of symptoms and treatment of syphilis and yaws by healthy blood donors screening positive for syphilis in Kumasi, Ghana

    Directory of Open Access Journals (Sweden)

    Francis Sarkodie

    2016-09-01

    Conclusions: A small proportion of confirmed seroreactive donors in this sample had any recall of symptoms or treatment for yaws or syphilis. These data suggest that clinical questioning adds little further information to the current screening algorithm. The relative contribution of yaws and syphilis to frequent positive tests in endemic areas remains speculative.

  2. The scrape-off layer in a finite-aspect-ratio Torus: The influence of limiter position

    International Nuclear Information System (INIS)

    Harbour, P.J.; Loarte, A.

    1995-01-01

    The effect on the scrape-off layer (SOL) of changing the position of a tokamak limiter from the low field side (LFS) to the high field side (HFS) of the plasma is considered. Conservation of magnetics flux in the SOL requires that the area, A parallel , for flow of particles and energy parallel to the magnetic field, be smaller on the HFS. The effect that this reduction in A parallel has on the SOL is that, when the limiter is on the HFS, as compared with the LFS, then the characteristic scrape-off thickness is increased and the plasma particle and energy densities are higher. Such increases are described. They were observed in an experiment in JET in which the plasma was limited first on the LFS and then, during the same discharge, on the HFS. The magnitude of the effect was larger than expected, with the line integrated density of the SOL, nλ n , having an average increase by a factor of 5.8 ± 1.1, and an increase by a factor of 7 at the respective limiter. Moreover, there was an increase in the characteristic scrape-off thickness for power flow, λ p , by a factor of 2.5 ± 0.4 on average, and a corresponding increase by a factor of 3.0 at the respective limiter. Such an increase in nλ n can substantially improve the screening of recycled particles and can increase wall pumping, although not strongly in the experiments described, which were in helium to avoid these effects. The large increase in λ p measured in JET is useful in spreading power over a larger area of a limiter on the HFS. Evidence is presented which suggests that either the observed enhancement of the effect on the SOL above expectations is due to a reduction in the Mach number at the limiter sheath when on the HFS or there are fundamental problems with the modelling procedure usually used for the SOL. Related experiments are discussed. (author). 29 refs, 3 figs, 3 tabs

  3. Limitations in the use of Drosophila melanogaster as a model host for gram-positive bacterial infection

    DEFF Research Database (Denmark)

    Jensen, Rikke Lind; Pedersen, K.S.; Loeschcke, V

    2007-01-01

    resistance respectively, were subjected to infection by L. monocytogenes, S. aureus and E. coli. Mortality rates were comparable with that of the Oregon R strain. Conclusions: Use of the injection method shows the limitation of D. melanogaster as a model host for gram-positive bacteria as opportunistic......Aims: To examine sensitivities of various Drosophila melanogaster strains towards human pathogenic and nonpathogenic gram-positive bacteria. Methods and Results: The D. melanogaster Oregon R strain was infected by injecting the thorax with a needle containing Escherichia coli (negative control...... with the negative control. Infection with L. innocua, B. subtilis or C. maltaromaticum also resulted in a high fly mortality, whereas Lact. plantarum and P. acidilactici resulted in a slightly increased mortality. Four additional D. melanogaster lines, three of which had been selected for heat, cold and desiccation...

  4. Local and global analysis of a speculative housing market with production lag

    Science.gov (United States)

    Campisi, Giovanni; Naimzada, Ahmad K.; Tramontana, Fabio

    2018-05-01

    We extend the model of Dieci and Westerhoff [J. Evol. Econ. 22(2), 303-329 (2012)], where the authors analyse a speculative housing market populated by heterogeneous interacting agents described by a two dimensional nonlinear discrete time dynamical system. They show the emergence of complicated dynamics through the occurrence of bifurcations for particular parameter combinations. We enlarge their model in several ways. On one hand, we introduce time lag in the supply side and we consider two new scenarios characterised by agents' expectations formation. First, naive expectations instead of perfect foresight are considered, while in the second scenario, we study a mix between the model of Dieci and Westerhoff [J. Evol. Econ. 22(2), 303-329 (2012)] and the one we propose. As a consequence, we, analytically and numerically, explain the appearance of instability in the housing market providing conditions on the parameters that lead to a bifurcation. On the other hand, thanks to further numerical simulations, we conduct a global analysis providing the structure of the basin of attractions of the map showing coexistence of attractors.

  5. Oil prices, speculation, and fundamentals. Interpreting causal relations among spot and futures prices

    International Nuclear Information System (INIS)

    Kaufmann, Robert K.; Ullman, Ben

    2009-01-01

    A consensus that the world oil market is unified begs the question, where do innovations in oil prices enter the market? Here we investigate where changes in the price of crude oil originate and how they spread by examining causal relationships among prices for crude oils from North America, Europe, Africa, and the Middle East on both spot and futures markets. Results indicate that innovations first appear in spot prices for Dubai-Fateh and spread to other spot and futures prices while other innovations first appear in the far month contract for West Texas Intermediate and spread to other exchanges and contracts. Links between spot and futures markets are relatively weak and this may have allowed the long-run relationship between spot and future prices to change after September 2004. Together, these results suggest that market fundamentals initiated a long-term increase in oil prices that was exacerbated by speculators, who recognized an increase in the probability that oil prices would rise over time. (author)

  6. The speculative activity of the investment funds in the NYMEX (New York Mercantile Exchange) oil future prices formation; A atividade especulativa dos fundos de investimento na formacao dos precos futuros de petroleo no NYMEX (New York Mercantile Exchange)

    Energy Technology Data Exchange (ETDEWEB)

    Amin, Mario Miguel [Universidade da Amazonia (UNAMA), Manaus, AM (Brazil); Luczynski, Estanislau [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Geociencias

    2008-07-01

    The increase in the NYMEX future's market oil prices can be explained not only by traditional economic fundamentals of demand and supply, but also by the significant speculative participation of the Investment Funds, as measured by the extraordinary increase in the non-commercial spread traders' open interest positions, as published by the Commodities Futures Trading Commission (CFTC). The open interest increased from 66,234 in May 23, 2000, to 974,159 on May 13, 2008. On that day, the NYMEX reached the historic quantity of 3,149,667 contracts, being the spread trading responsible for 31% of that total. In terms of market liquidity, that percentage represented US$ 119,8 millions applied in the oil futures market. Given the availability of information from the NYMEX and CFTC, the objective of the study was to identify the participation, position and level of influence of the Investment Funds in the determination of international oil prices during the 2000 to 2008 period. The results of the analysis of the international oil prices behavior, in the NYMEX, show that a large portion of the price volatility, during the period 2000 to 2008, and more specifically in 2006 through 2008, was due to the significant process of speculation by the Investment Funds. Needing to recover the losses caused by the subprimes crisis, by the drop in the Wall Street's stock value and, specially, by the intense dollar devaluation in recent years, the Investment Funds sought cover in the commodities market, particularly in the oil futures market. (author)

  7. Quantum Computing and the Limits of the Efficiently Computable

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    I'll discuss how computational complexity---the study of what can and can't be feasibly computed---has been interacting with physics in interesting and unexpected ways. I'll first give a crash course about computer science's P vs. NP problem, as well as about the capabilities and limits of quantum computers. I'll then touch on speculative models of computation that would go even beyond quantum computers, using (for example) hypothetical nonlinearities in the Schrodinger equation. Finally, I'll discuss BosonSampling ---a proposal for a simple form of quantum computing, which nevertheless seems intractable to simulate using a classical computer---as well as the role of computational complexity in the black hole information puzzle.

  8. Speculation of the Time-Dependent Change of FIB4 Index in Patients with Nonalcoholic Fatty Liver Disease: A Retrospective Study.

    Science.gov (United States)

    Miyata, Hiroshi; Miyata, Satoru

    2018-01-01

    To speculate on the time-dependent change of FIB4 index in patients with nonalcoholic fatty liver disease (NAFLD) and its increase-decrease rate per year, simply and accurately. In all 23 patients with NAFLD with the value of FIB4 index over 1.30 at the peak, the period from the first to each examination date was calculated and this period (years) was regarded as x . Next, the mean value of FIB4 index during the past year to each examination date was regarded as y . In every y , the minimum and the maximum y value were found out. Between x corresponding to this minimum y and x corresponding to this maximum y , the correlation between x and y was analyzed as the main subject. Then, the slope of each correlation was investigated, because it should indicate increase-decrease rate per year. In all 23 patients, the correlations as the main subject were recognized and the mean absolute value of correlation coefficient ( r ) was 0.91 ± 0.08. As for the slope, the mean absolute value was 0.1371 ± 0.1147 (/year). Simply and accurately, the time-dependent change of FIB4 index and its increase-decrease rate per year could be approximately speculated.

  9. HER2-positive male breast cancer with thyroid cancer: an institutional report and review of literature.

    Science.gov (United States)

    Bardhan, Pooja; Bui, Marilyn M; Minton, Susan; Loftus, Loretta; Carter, W Bradford; Laronga, Christine; Ismail-Khan, Roohi

    2012-01-01

    We report a rare finding of two male breast cancer patients with HER2-positive breast cancer who also developed thyroid cancer. We reviewed 45 male breast cancer patients treated in our institution from 2003 to 2008. Only five male breast cancer patients were HER2-positive. In reviewing the published data, we found no cases of thyroid cancer and concurrent breast cancer in men. However, breast cancer and thyroid cancer have shown close association in women. This finding therefore provokes speculation as to whether we should investigate whether women with HER2-positive breast cancer are at a higher risk for thyroid cancer. Although this observation seems to be clinically prevalent, publications are sparse in clinical research areas linking thyroid cancer to breast cancer.

  10. Speculation and volatility spillover in the crude oil and agricultural commodity markets: A Bayesian analysis

    International Nuclear Information System (INIS)

    Du Xiaodong; Yu, Cindy L.; Hayes, Dermot J.

    2011-01-01

    This paper assesses factors that potentially influence the volatility of crude oil prices and the possible linkage between this volatility and agricultural commodity markets. Stochastic volatility models are applied to weekly crude oil, corn, and wheat futures prices from November 1998 to January 2009. Model parameters are estimated using Bayesian Markov Chain Monte Carlo methods. Speculation, scalping, and petroleum inventories are found to be important in explaining the volatility of crude oil prices. Several properties of crude oil price dynamics are established, including mean-reversion, an asymmetry between returns and volatility, volatility clustering, and infrequent compound jumps. We find evidence of volatility spillover among crude oil, corn, and wheat markets after the fall of 2006. This can be largely explained by tightened interdependence between crude oil and these commodity markets induced by ethanol production.

  11. Speculative promise as a driver in climate engineering research: The case of Paul Crutzen's back-of-the-envelope calculation on solar dimming with sulfate aerosols

    NARCIS (Netherlands)

    van Hemert, M.

    2017-01-01

    In this paper, I study the generative role of speculative promise in climate engineering research. My analysis operationalizes Alfred Nordmann's call for a 'forensics of wishing', a variety of technology assessment which scrutinizes the politics of anticipation in technoscience. Using scientific

  12. A teoria da libido em Freud como uma hipótese especulativa Freud's theory of libido as a speculative hypothesis

    Directory of Open Access Journals (Sweden)

    Leopoldo Fulgencio

    2002-06-01

    Full Text Available Comenta-se a distinção freudiana entre a sexualidade, como um fato observável, e a libido, como uma hipótese especulativa, mostrando que, para Freud, a suposição de uma energia específica para a pulsão sexual corresponde a um conceito que tem validade apenas instrumental - ou seja, heurística - não sendo uma referência empírica objetiva. Salienta-se que Freud não considera os conceitos desse tipo - especulativos - o fundamento da sua ciência, mas sim o cume substituível do edifício teórico da psicanálise. Esse tipo de interpretação da obra de Freud, que o integra na história da filosofia e da ciência alemãs, permite não só compreender a psicanálise como uma ciência numa perspectiva heurística, como também possibilita uma análise dos desenvolvimentos da psicanálise levando em conta a diferença entre dados empíricos e teóricos (especulativos, e explicando, assim, em que sentido a teoria psicanalítica é considerada por Freud como provisória e sempre aberta a revisões.This article comments on the Freudian distinction between sexuality, as an observable fact, and libido, as a speculative hypothesis, demonstrating that, for Freud, the supposition of a specific energy for sexual drive corresponds to a concept that has only instrumental - or heuristic - validity rather than an objective empirical reference. It is also pointed out that Freud does not consider the concepts of this type - speculative - to be the basis of his science, but the replaceable apogee of the theoretical edifice of psychoanalysis. This type of interpretation of Freud's work,, which integrates it in the history of German philosophy and science, permits not only the comprehension of psychoanalysis as a science from a heuristic perspective but also makes possible an analysis of the developments of psychoanalysis that takes into account the difference between empirical and theoretical (speculative data, explaining in what sense the psychoanalytical

  13. Speculative science (“fairy tale science” in physics, cosmology, and economics

    Directory of Open Access Journals (Sweden)

    Richard Mattessich

    2016-12-01

    Full Text Available The paper juxtaposes two recent books dealing with reality issues in a broad sense. The first of these, by Baggott (2013, examines and criticizes the historically increasing trend to base scientific conclusions on mathematical hypotheses and logical consistency rather than on empirical evidence -- Bagott calls this trend “fairy tale science”. The second book, Tegmark (2014,i defends the opposite view – it considers Mathematics as identical to Reality and promotes increasing reliance of modern physics and cosmology on mathematical assumptions and logical consistencies rather than empirical evidence -- defending such controversial conclusions that we live in one of infinitely many parallel universes with numerous alter egos of each of us. But this is not a book review of Baggott (2013 and Tegmark (2014; its aim is to draw attention to the fact that social scientists are not the only scholars blamed for paying too much attention to model building and too little to empirical confirmation. This, ought to be of enormous interest to financial scholars; it may even be a consolation to some of them for emphasizing mathematical consistency rather than empirical confirmation. But our examples (from “speculative science” in finance illustrate that such a trend caused staggering losses during the financial crisis of 1997-1998 (of Japan and Russia and serious threats to the entire World Economic System during the crisis of 2007-2008.

  14. Changes in seed oil and protein contents of maize cultivars at different positions on the ear in response to water limitation

    Directory of Open Access Journals (Sweden)

    Kazem Ghassemi-Golezani

    2016-10-01

    Full Text Available A field experiment was carried out as split-split plot in 2014 to assess the effects of four irrigation treatments (irrigations after 60, 80, 100 and 120 mm evaporation, respectively on oil and protein changes of maize cultivars (SC704, NS640 and DC303: Late, mid and early maturing cultivars, respectively at different seed positions on the ear (upper, middle and lower positions on the ear. Overall, the highest seed yield was obtained from SC704, followed by NS640 and DC303 cultivars. Seed yield of all cultivars was higher at lower seed position on ear than at middle and upper parts of the ear under different irrigation treatments. The highest oil and protein yields were also recorded for seeds at lower position on the ear. Seed yield of all maize cultivars at various seed positions decreased with increasing irrigation intervals. Oil percentage decreased, but protein percentage increased with decreasing water availability. Water limitation decreased oil and protein yields of maize cultivars. Changes in protein and oil yields of maize cultivars at different seed positions and irrigation treatments were attributed to changes in seed yield.

  15. Limits to human enhancement: nature, disease, therapy or betterment?

    Science.gov (United States)

    Hofmann, Bjørn

    2017-10-10

    New technologies facilitate the enhancement of a wide range of human dispositions, capacities, or abilities. While it is argued that we need to set limits to human enhancement, it is unclear where we should find resources to set such limits. Traditional routes for setting limits, such as referring to nature, the therapy-enhancement distinction, and the health-disease distinction, turn out to have some shortcomings. However, upon closer scrutiny the concept of enhancement is based on vague conceptions of what is to be enhanced. Explaining why it is better to become older, stronger, and more intelligent presupposes a clear conception of goodness, which is seldom provided. In particular, the qualitative better is frequently confused with the quantitative more. We may therefore not need "external" measures for setting its limits - they are available in the concept of enhancement itself. While there may be shortcomings in traditional sources of limit setting to human enhancement, such as nature, therapy, and disease, such approaches may not be necessary. The specification-of-betterment problem inherent in the conception of human enhancement itself provides means to restrict its unwarranted proliferation. We only need to demand clear, sustainable, obtainable goals for enhancement that are based on evidence, and not on lofty speculations, hypes, analogies, or weak associations. Human enhancements that specify what will become better, and provide adequate evidence, are good and should be pursued. Others should not be accepted.

  16. Cold aqueous planetary geochemistry with FREZCHEM from modeling to the search for life at the limits

    CERN Document Server

    Marion, Giles M

    2007-01-01

    This book explicitly investigates issues of astrobiological relevance in the context of cold aqueous planetary geochemistry. At the core of the technical chapters is the FREZCHEM model, initially developed over many years by one of the authors to quantify aqueous electrolyte properties and chemical thermodynamics at subzero temperatures. FREZCHEM, of general relevance to biogeochemists and geochemical modelers, cold planetary scientists, physicochemists and chemical engineers, is subsequently applied to the exploration of biogeochemical applications to solar systems bodies in general, and to speculations about the limits for life in cold environments in particular.

  17. TFTR movable limiter instrumentation and controls

    International Nuclear Information System (INIS)

    Frankenberg, J.; Collins, D.; Kaufmann, D.; Mamoun, A.

    1983-01-01

    The TFTR movable limiter is a single poloidal limiter located within one 18 /SUP o/ segment of the vacuum vessel. It consists of three (3) interconnected inconel backing plates covered with titanium carbide coated graphite tiles. The backing plates are positioned by three independent screw drive actuators. Cooling water is fed through the horizontal port cover to tubes brazed onto the backs of the backing plates. Thermocouples monitor the limiter temperature. (1) and more fully described in refs. (1) and (2). The positioning actuators are driven by independently controlled DC servo motors, controlled either locally or from CICADA. Drive motor shaft position is monitored by chain driven encoders and potentiometers. Limiter blade position can be varied to suit any plasma within the operating range. CICADA is programmed to keep the limiter stroke within safe operating limits. A microprocessor duplicates the CICADA protective function allowing limiter operation without CICADA. The potentiometer signal is sent to an analog computer, which safeguards the limiter against failure of the encoders or the micro-processor. Cooling water flows through the limiter in 3 separate paths, one for each blade. The flow rate and temperature rise through each loop are measured accurately to allow CICADA to calculate the heat into each blade. The water system is also interlocked and alarmed to prevent dumping of water into the vacuum vessel

  18. The effect of differentiated margin on futures market investors' behavior and structure An experimental research

    Institute of Scientific and Technical Information of China (English)

    Jin-hui Luo; Di-fang Wan; Yang Yang; Guang Yang

    2011-01-01

    Purpose-The purpose of this paper is to empirically analyze the role of differentiated margin system in leading investors' investing behavior and then optimize investor structure in futures markets.Design/methodology/approach-Using economic experimental research method,this paper designs and conducts a futures market experiment according to experimental research's basic norms,thus acquiring needed and credible empirical data.Findings-By analyzing the experimental data,it is found that compared with situations in futures markets that implement uniform margin system,investors' (especially speculators') futures open position and the ratio of their open position and futures turnover are both significantly higher,in futures markets that implement differentiated margin system.On the other hand,differentiated margin system has no effects on hedgers' futures turnover,but significantly reduces speculators' futures turnover.Research limitations/implications-The findings suggest that compared with uniform margin system,differentiated margin system is beneficial to effectively restrict both speculators' and hedgers' speculating behavior and lead hedgers' market participation.Practical implications-In order to resolve the problem of unreasonable investor structure in China's futures market,i.e.lack of hedgers and over-speculating China's futures market's regulators should reform the margin system and adopt differentiated margin system to lead investors' rational behavior and optimize investor structure.Originality/value-This paper empirically analyzes and verifies,for the first time,the roles of differentiated margin system in affecting investors' investing behavior.The futures market experiment designed and used in this study is a pioneering and exploratory experiment.

  19. The recognition of autism in children with Down syndrome--implications for intervention and some speculations about pathology.

    Science.gov (United States)

    Howlin, P; Wing, L; Gould, J

    1995-05-01

    Although autism can occur in conjunction with a range of other conditions, the association with Down syndrome is generally considered to be relatively rare. Four young boys with Down syndrome are described who were also autistic. All children clearly fulfilled the diagnostic criteria for autism required by the ICD-10 or DSM-III-R, but in each case the parents had faced considerable difficulties in obtaining this diagnosis. Instead, the children's problems had been attributed to their cognitive delays, despite the fact that their behaviour and general progress differed from other children with Down syndrome in many important aspects. The implications, for both families and children, of the failure to diagnose autism when it co-occurs with other conditions such as Down syndrome are discussed. Some speculations about possible pathological associations are also presented.

  20. Intrinsic spatial resolution limitations due to differences between positron emission position and annihilation detection localization

    International Nuclear Information System (INIS)

    Perez, Pedro; Malano, Francisco; Valente, Mauro

    2012-01-01

    Since its successful implementation for clinical diagnostic, positron emission tomography (PET) represents the most promising medical imaging technique. The recent major growth of PET imaging is mainly due to its ability to trace the biologic pathways of different compounds in the patient's body, assuming the patient can be labeled with some PET isotope. Regardless of the type of isotope, the PET imaging method is based on the detection of two 511-keV gamma photons being emitted in opposite directions, with almost 180 deg between them, as a consequence of electron-positron annihilation. Therefore, this imaging method is intrinsically limited by random uncertainties in spatial resolutions, related with differences between the actual position of positron emission and the location of the detected annihilation. This study presents an approach with the Monte Carlo method to analyze the influence of this effect on different isotopes of potential implementation in PET. (author)

  1. Detecting Position Using ARKit II: Generating Position-Time Graphs in Realtime and Further Information on Limitations of ARKit

    Science.gov (United States)

    Dilek, Ufuk; Erol, Mustafa

    2018-01-01

    ARKit is a framework which allows developers to create augmented reality apps for the iPhone and iPad. In a previous study, we had shown that it could be used to detect position in educational physics experiments and emphasized that the ability to provide position data in real-time was one of the prominent features of this newly emerging…

  2. Mass fractionation of noble gases in diffusion-limited hydrodynamic hydrogen escape

    International Nuclear Information System (INIS)

    Zahnle, K.; Pollack, J.B.; Kasting, J.F.

    1990-01-01

    The theory of mass fractionation by hydrogen is presently extended to atmospheres in which hydrogen is not the major constituent. This theoretical framework is applied to three different cases. In the first, it is shown that the fractionation of terrestrial atmospheric neon with respect to mantle neon is explainable as a consequence of diffusion-limited hydrogen escape from a steam atmosphere toward the end of the accretion process. In the second, the anomalously high Ar-38/Ar-36 ratio of Mars is shown to be due to hydrodynamic fractionation by a vigorously escaping and very pure hydrogen wind. In the last case, it is speculated that the currently high Martian D/H ratio emerged during the hydrodynamic escape phase which fractionated Ar. 35 refs

  3. Navicular bone position determined by positional MRI

    DEFF Research Database (Denmark)

    Hansen, Philip; Johannsen, Finn E; Hangaard, Stine

    2016-01-01

    -scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). RESULTS...

  4. Speculations on the dynamics of Jupiter's atmosphere from 1 to 100 bars

    Science.gov (United States)

    Ingersoll, A. P.

    2017-12-01

    The latitude-altitude map of ammonia mixing ratio shows an ammonia-rich zone at 0-5°N, with mixing ratios of 320-340 ppm, extending from 40-60 bars up to the ammonia cloud base at 0.7 bars. Ammonia-poor air occupies a belt from 5-20°N. We argue that downdrafts as well as updrafts are needed in the 0-5°N zone to balance the upward ammonia flux. Outside the 0-20°N region, the belt-zone signature is weaker. At latitudes out to ±40°, there is an ammonia-rich layer from cloud base down to 2 bars which we argue is caused by falling precipitation. Below, there is an ammonia-poor layer with a minimum at 6 bars. Unanswered questions include how the ammonia-poor layer is maintained, why the belt-zone structure is barely evident in the ammonia distribution outside 0-20°N, and how the internal heat is transported through the ammonia-poor layer to the ammonia cloud base. Here we speculate on possible answers, including double-diffusive convection, deep abyssal overturning, and mass loading of heavy condensates in a hydrogen/helium atmosphere. Ingersoll, A. P. et al. (2017). Implications of the ammonia distribution on Jupiter from 1 to 100 bars as measured by the Juno microwave radiometer. Geophys. Res. Lett., in press, doi: 10.1002/2017GL074277.

  5. How bright planets became dim stars: planetary speculations in John Herschel's double star astronomy.

    Science.gov (United States)

    Case, Stephen

    2014-03-01

    Previous research on the origins of double star astronomy in the early nineteenth century emphasized the role mathematical methods and instrumentation played in motivating early observations of these objects. The work of the British astronomer John Herschel, however, shows that questions regarding the physical nature of double stars were also important. In particular, an analysis of John Herschel's early work on double stars illustrates the way in which speculations regarding these objects were shaped by assumptions of the properties of stars themselves. For Herschel, a major consideration in double star astronomy was distinguishing between types of double stars. Optical doubles were useful in determining parallax while binary doubles were not. In practice, classification of a specific double star pair into one of these categories was based on the assumption that stars were of approximately the same luminosity and thus differences in relative brightness between stars were caused by difference in distances. Such assumptions, though ultimately abandoned, would lead Herschel in the 1830s to advance the possibility that the dim companion stars in certain double star pairs were not stars at all but in fact planets. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Moderate hypofractionated image-guided thoracic radiotherapy for locally advanced node-positive non-small cell lung cancer patients with very limited lung function: a case report

    International Nuclear Information System (INIS)

    Manapov, Farkhad; Roengvoraphoj, Olarn; Li, Ming Lun; Eze, Chukwuka

    2017-01-01

    Patients with locally advanced lung cancer and very limited pulmonary function (forced expiratory volume in 1 second [FEV1] ≤ 1 L) have dismal prognosis and undergo palliative treatment or best supportive care. We describe two cases of locally advanced node-positive non-small cell lung cancer (NSCLC) patients with very limited lung function treated with induction chemotherapy and moderate hypofractionated image-guided radiotherapy (Hypo-IGRT). Hypo-IGRT was delivered to a total dose of 45 Gy to the primary tumor and involved lymph nodes. Planning was based on positron emission tomography-computed tomography (PET/ CT) and four-dimensional computed tomography (4D-CT). Internal target volume (ITV) was defined as the overlap of gross tumor volume delineated on 10 phases of 4D-CT. ITV to planning target volume margin was 5 mm in all directions. Both patients showed good clinical and radiological response. No relevant toxicity was documented. Hypo-IGRT is feasible treatment option in locally advanced node-positive NSCLC patients with very limited lung function (FEV1 ≤ 1 L)

  7. Moderate hypofractionated image-guided thoracic radiotherapy for locally advanced node-positive non-small cell lung cancer patients with very limited lung function: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Manapov, Farkhad; Roengvoraphoj, Olarn; Li, Ming Lun; Eze, Chukwuka [Dept. of Radiation Oncology, Ludwig-Maximilian University of Munich, Munich (Germany)

    2017-06-15

    Patients with locally advanced lung cancer and very limited pulmonary function (forced expiratory volume in 1 second [FEV1] ≤ 1 L) have dismal prognosis and undergo palliative treatment or best supportive care. We describe two cases of locally advanced node-positive non-small cell lung cancer (NSCLC) patients with very limited lung function treated with induction chemotherapy and moderate hypofractionated image-guided radiotherapy (Hypo-IGRT). Hypo-IGRT was delivered to a total dose of 45 Gy to the primary tumor and involved lymph nodes. Planning was based on positron emission tomography-computed tomography (PET/ CT) and four-dimensional computed tomography (4D-CT). Internal target volume (ITV) was defined as the overlap of gross tumor volume delineated on 10 phases of 4D-CT. ITV to planning target volume margin was 5 mm in all directions. Both patients showed good clinical and radiological response. No relevant toxicity was documented. Hypo-IGRT is feasible treatment option in locally advanced node-positive NSCLC patients with very limited lung function (FEV1 ≤ 1 L)

  8. 77 FR 31767 - Aggregation, Position Limits for Futures and Swaps

    Science.gov (United States)

    2012-05-30

    ... submitted in English, or if not, accompanied by an English translation. Comments will be posted as received... significant costs to monitor positions on an intra-day basis, notwithstanding the current lack of control over... filing for disaggregation relief and the owned entity do not have knowledge of the trading decisions of...

  9. A speculation on the debate about the future electricity demand in Korea

    International Nuclear Information System (INIS)

    Lim, Chae Young; Moon, Kee Hwan

    2005-01-01

    Since 1991, Korean government established the Long term Power Development Plan(LPDP) to secure a stable electricity supply. With the introduction of market mechanism into electricity supply sector, that plan has been changed into the Basic Plan of the Electricity supply and demand(BPE), which plays a role as a nonbinding guideline or a reference rather than the implementation plan. The BPE still has its importance as a tool providing market participants with appropriate information of future electricity market. According to the second BPE, released at the end of 2004, electricity demand is projected to grow at 2.5% per annum and reach 416.5TWh in 2017 from 293.6TWh in 2003. Based on the projected demand, power expansion plan provided by utilities has established. In the process of formulating the BPE, there were hot debates on the excess capacity margins for certain period of planning time. Some people, especially from environmental groups maintained that many Koreans were wasteful with electricity so that stronger policy for curbing the electricity consumption should be introduced rather than commissioning of additional power plants. They referred to relatively high number of the electricity intensity of Korea as the grounds of their argument. However, electricity intensity in a region or a country is influenced by various factors and higher intensity does not necessarily mean more wasteful consumption of electricity. We have compared various aspects of electricity demand in Korea with other countries to speculate the argument that electricity consumption in Korea is too high. We have also discussed electricity projection in the BPE

  10. Leisure Activity Engagement and Positive Affect Partially Mediate the Relationship Between Positive Views on Aging and Physical Health.

    Science.gov (United States)

    Hicks, Stephanie A; Siedlecki, Karen L

    2017-03-01

    To examine leisure activity engagement and positive affect as potential mediators for the relationships between positive views on aging (PVA) and two health outcomes: subjective health and physical limitations. Data from 5,194 participants from the German Ageing Survey (aged 40-91 years) were used to examine relationships between PVA to subjective health (assessed by self-rated health and perceived health change from past) and physical limitations (assessed via self-reported limitations on 10 activities). Leisure activity engagement and positive affect were examined as potential mediators in latent variable path analyses. Age moderation among these relationships was also examined. Leisure activity engagement and positive affect separately and jointly served to partially mediate the relationships between PVA and the health outcomes. When entered as joint mediators, positive affect no longer significantly predicted physical limitations, indicating a shared variance with leisure activity engagement. Age moderated the relationship between PVA and physical limitations; the relationship was stronger among older adults than among middle-aged adults. Leisure activity engagement and positive affect were shown to help explain the relationship between PVA and health, but differently for different health constructs and also among middle-aged and older adults. Findings provide further insight into ways in which PVA influence health. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Which way the natural gas price. An attempt to predict the direction of natural gas spot price movements using trader positions

    International Nuclear Information System (INIS)

    Buchanan, W.K.; Hodges, P.; Theis, J.

    2001-01-01

    This research provides a method of predicting direction of spot price movements in the natural gas market for the month succeeding from market participants positions in the futures market. Cumby and Modest (Cumby, R.E., Modest, D.M., 1987. Testing for market timing ability: a framework for forecast evaluation. Journal of Financial Economics 19, 169-189) provide the backdrop for analyzing the futures market positions of large hedgers and speculators to arrive at conclusions of market price movements in the spot market. This methodology is suggested as a means for municipalities entering the natural gas market to improve upon their ordering of quantities of gas for the ensuing months in order to take advantage of possibly foreseeable price trends

  12. Multi-technology positioning

    CERN Document Server

    Lohan, Elena-Simona; Wymeersch, Henk; Seco-Granados, Gonzalo; Nykänen, Ossi

    2017-01-01

    This book provides an overview of positioning technologies, applications and services in a format accessible to a wide variety of readers. Readers who have always wanted to understand how satellite-based positioning, wireless network positioning, inertial navigation, and their combinations work will find great value in this book. Readers will also learn about the advantages and disadvantages of different positioning methods, their limitations and challenges. Cognitive positioning, adding the brain to determine which technologies to use at device runtime, is introduced as well. Coverage also includes the use of position information for Location Based Services (LBS), as well as context-aware positioning services, designed for better user experience. • Brings understanding of positioning technology to readers from a variety of disciplines • Reviews multiple techniques, providing insight on the pros, cons and challenges related to each • Designed to be a tutorial on basic principles, avoiding unnecessary de...

  13. Rational speculative bubbles: A critical view

    Directory of Open Access Journals (Sweden)

    Radonjić Ognjen

    2007-01-01

    Full Text Available According to the theory of rational bubbles, the bubble is present whenever asset prices progressively diverge from their fundamental value, which occurs because agents expect that asset prices will continue to grow exponentially (self-fulfilling prophecies far in the future and consistently, which promises the realization of ever larger capital gains. In our opinion, the basic shortcoming of this theory refers to the assumption that all market agents are perfectly informed and rational and, accordingly, form homogeneous expectations. The model does not explain decision-making processes or expectation formation, nor does it detect potential psychological and institutional factors that might significantly influence decision making processes and market participants’ reactions to news. Since assumptions of the model critically determine its validity, we conclude that comprehensiveness of the rational bubble model is, to put it mildly, limited.

  14. Ordinal Position Research Related to Vocational Interest

    Science.gov (United States)

    Gandy, Gerald L.

    1974-01-01

    Birth order studies directly related to vocational interest were reviewed to discern support for certain theoretical susumptions: firstborns are more directing, controlling, and organizing than later borns and later borns are more sociable, empathic, and sympathetic than firstborns. The research was inconsistent, contradictory, and speculative.…

  15. Prefrontal serotonin transporter availability is positively associated with the cortisol awakening response

    DEFF Research Database (Denmark)

    Frokjaer, Vibe Gedsoe; Erritzoe, David; Holst, Klaus Kähler

    2013-01-01

    higher cortisol responses when exposed to psychosocial stressors relative to high expressing 5-HTTLPR variants. However, it is not clear how the relation between SERT and cortisol output is reflected in the adult brain. We investigated the relation between cortisol response to awakening (CAR) and SERT...... binding in brain regions considered relevant to modify the cortisol awakening response. Methods: thirty-two healthy volunteers underwent in vivo SERT imaging with [11C]DASB-Positron Emission Tomography (PET), genotyping, and performed home-sampling of saliva to assess CAR. Results: CAR, defined...... between CAR and prefrontal SERT binding as tested by an interaction analysis (genotype×CAR). Conclusion: prefrontal SERT binding is positively associated with cortisol response to awakening. We speculate that in mentally healthy individuals prefrontal serotonergic neurotransmission may exert an inhibitory...

  16. Simulated reduction of hypoxia in the northern Gulf of Mexico due to phosphorus limitation

    Directory of Open Access Journals (Sweden)

    Arnaud Laurent

    2014-02-01

    Full Text Available Abstract Excess nutrient loading from the Mississippi-Atchafalaya River system promotes the seasonal development of hypoxic bottom waters on the Louisiana shelf with detrimental effects on the benthic fauna. In the Mississippi River plume, primary production becomes phosphorus-limited between May and July at the peak of nutrient loading, displacing a portion of primary production and depositional fluxes westward. Here we quantitatively assessed, for the first time, the effect of phosphorus limitation on hypoxia development in the Mississippi-Atchafalaya River plume using a realistic physical-biogeochemical model. Results indicate that, despite a redistribution of respiration processes toward the western shelf, phosphorus limitation does not promote a westward expansion or relocation of hypoxia, as previously speculated. Rather, the onset of hypoxia was delayed and the size of the hypoxic zone reduced. Sensitivity experiments showed that this feature is robust in our model. Results from simulations with altered river input indicate that, despite phosphorus limitation, the co-reduction of nitrogen and phosphorus loads remains the best strategy to reduce hypoxia. Yet, even though nutrient load reductions have an immediate effect on hypoxia in this analysis, a 50% reduction in both nutrients will not be sufficient to meet the Gulf Hypoxia action plan goal of a 5·103 km2 hypoxic area.

  17. Decreased carbon limitation of litter respiration in a mortality-affected piñon–juniper woodland

    Directory of Open Access Journals (Sweden)

    E. Berryman

    2013-03-01

    Full Text Available Microbial respiration depends on microclimatic variables and carbon (C substrate availability, all of which are altered when ecosystems experience major disturbance. Widespread tree mortality, currently affecting piñon–juniper ecosystems in southwestern North America, may affect C substrate availability in several ways, for example, via litterfall pulses and loss of root exudation. To determine piñon mortality effects on C and water limitation of microbial respiration, we applied field amendments (sucrose and water to two piñon–juniper sites in central New Mexico, USA: one with a recent (2 flux on the girdled site and a non-significant increase on the control. We speculate that the reduction may have been driven by water-induced carbonate dissolution, which serves as a sink for CO2 and would reduce the net flux. Widespread piñon mortality may decrease labile C limitation of litter respiration, at least during the first growing season following mortality.

  18. Method for limiting movement of a thermal shield for a nuclear reactor, and thermal shield displacement limiter therefor

    International Nuclear Information System (INIS)

    Meuschke, R.E.; Boyd, C.H.

    1989-01-01

    This patent describes a method of limiting the movement of a thermal shield of a nuclear reactor. It comprises: machining at least four (4) pockets in upper portions of a thermal shield circumferentially about a core barrel of a nuclear reactor to receive key-wave inserts; tapping bolt holes in the pockets of the thermal shield to receive bolts; positioning key-wave inserts into the pockets of the thermal shield to be bolted in place with the bolt holes; machining dowel holes at least partially through the positioned key-way inserts and the thermal shield to receive dowel pins; positioning dowel pins in the dowel holes in the key-way insert and thermal shield to tangentially restrain movement of the thermal shield relative to the core barrel; sliding limiter keys into the key-way inserts and bolting the limiter keys to the core barrel to tangentially restrain movement of the thermal shield relative and the core barrel while allowing radial and axial movement of the thermal shield relative to the core barrel; machining dowel holes through the limiter key and at least partially through the core barrel to receive dowel pins; positioning dowel pins in the dowel holes in the limiter key and core barrel to restrain tangential movement of the thermal shield relative to the core barrel of the nuclear reactor

  19. Corporate brand positioning : searching for a new position - case Metso Power

    OpenAIRE

    KUURU, TIINA-KAISA

    2013-01-01

    Tutkielmasta TamPubissa rajattu versio. Täydellinen versio luettavissa Tampereen yliopiston Linna-kirjastossa. This is a limited version of the Master's thesis. The complete version can be viewed in print at Tampere University Library The purpose of this study is to describe and analyse the process of corporate brand positioning. Study is focused on B2B market, precisely on industrial brands. Corporate brand positioning is defined as a process of searching and finding a...

  20. 17 CFR 150.4 - Aggregation of positions.

    Science.gov (United States)

    2010-04-01

    ... ownership interest of limited partners, shareholders, members of a limited liability company, beneficiaries... by limited partners, shareholders or other pool participants. For the purpose of applying the... 10% or greater in an account or positions as a limited partner, shareholder or other similar type of...

  1. High rate behavior and discharge limits in micro-pattern detectors

    CERN Document Server

    Bressan, A; Pagano, P; Ropelewski, Leszek; Sauli, Fabio; Biagi, S F; Buzulutskov, A F; Gruwé, M; De Lentdecker, G; Mörmann, D; Sharma, A

    1999-01-01

    We present and discuss a set of systematic measurements, carried out with gaseous proportional micro-pattern detectors, in order to assess their maximum gain when irradiated with high-rate soft X-rays and heavily ionizing alpha particles. The inventory of detectors tested includes: micro-strip micromegas, micro-dot, gas electron multiplier, CAT (compteur à trous), trench (or groove), micro-CAT (or WELL) detectors, as well as systems with two elements of gaseous amplification in cascade. We confirm the general trend of all single-stage detectors to follow Raether's criterion, i.e. a spontaneous transition from avalanche to streamer, followed by a discharge, when the avalanche size reaches a value of a few 10 7 ; a noticeable exception is the micro-dot counter holding more than 10 8. In multiple structures, where the gain under irradiation is increased by at least one order of magnitude; we speculate this to be a consequence of a voltage dependence of Raether's limit, larger for low operating potentials. Our c...

  2. Deformed special relativity as an effective flat limit of quantum gravity

    International Nuclear Information System (INIS)

    Girelli, Florian; Livine, Etera R.; Oriti, Daniele

    2005-01-01

    We argue that a (slightly) curved space-time probed with a finite resolution, equivalently a finite minimal length, is effectively described by a flat non-commutative space-time. More precisely, a small cosmological constant (so a constant curvature) leads the κ-deformed Poincare flat space-time of deformed special relativity (DSR) theories. This point of view eventually helps understanding some puzzling features of DSR. It also explains how DSR can be considered as an effective flat (low energy) limit of a (true) quantum gravity theory. This point of view leads us to consider a possible generalization of DSR to arbitrary curvature in momentum space and to speculate about a possible formulation of an effective quantum gravity model in these terms. It also leads us to suggest a doubly deformed special relativity framework for describing particle kinematics in an effective low energy description of quantum gravity

  3. How Computers Are Used in the Teaching of Music and Speculations about How Artificial Intelligence Could Be Applied to Radically Improve the Learning of Compositional Skills. CITE Report No. 6.

    Science.gov (United States)

    Holland, Simon

    This paper forms part of a preliminary survey for work on the application of artificial intelligence theories and techniques to the learning of music composition skills. The paper deals with present day applications of computers to the teaching of music and speculations about how artificial intelligence might be used to foster music composition in…

  4. Navicular bone position determined by positional MRI: a reproducibility study

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Philip; Nybing, Janus D. [Copenhagen University Hospital Frederiksberg and Bispebjerg, Department of Radiology, Frederiksberg (Denmark); Johannsen, Finn E.; Stallknecht, Sandra E. [Copenhagen University Hospital Bispebjerg, Institute of Sports Medicine Copenhagen, Copenhagen, NV (Denmark); Hangaard, Stine; Hansen, Bjarke B. [Copenhagen University Hospital Frederiksberg, Parker Institute, Department of Rheumatology, Frederiksberg (Denmark); Boesen, Mikael [Copenhagen University Hospital Frederiksberg and Bispebjerg, Department of Radiology, Frederiksberg (Denmark); Copenhagen University Hospital Frederiksberg, Parker Institute, Department of Rheumatology, Frederiksberg (Denmark)

    2016-02-15

    To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). Intraobserver and interobserver reliability was ''substantial'' in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was ''moderate'' for NVH (ICC 0.72) and ''slight'' for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors. (orig.)

  5. Navicular bone position determined by positional MRI: a reproducibility study

    International Nuclear Information System (INIS)

    Hansen, Philip; Nybing, Janus D.; Johannsen, Finn E.; Stallknecht, Sandra E.; Hangaard, Stine; Hansen, Bjarke B.; Boesen, Mikael

    2016-01-01

    To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP). Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%). Intraobserver and interobserver reliability was ''substantial'' in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was ''moderate'' for NVH (ICC 0.72) and ''slight'' for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %). Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors. (orig.)

  6. On the use of one-dimensional position sensitive detector for x-ray diffraction reciprocal space mapping: Data quality and limitations

    International Nuclear Information System (INIS)

    Masson, Olivier; Boulle, Alexandre; Guinebretiere, Rene; Lecomte, Andre; Dauger, Alain

    2005-01-01

    A homemade x-ray diffractometer using one-dimensional position sensitive detector (PSD) and well suited to the study of thin epitaxial layer systems is presented. It is shown how PSDs can be advantageously used to allow fast reciprocal space mapping, which is especially interesting when analyzing poor crystalline and defective layers as usually observed with oxides and ceramics films. The quality of the data collected with such a setup and the limitations of PSDs in comparison with the use of analyzer crystals are discussed. In particular, the effects of PSD on angular precision, instrument resolution and corrections that must be applied to raw data are presented

  7. Pretty Easy Pervasive Positioning

    DEFF Research Database (Denmark)

    Hansen, Rene; Wind, Rico; Jensen, Christian Søndergaard

    2009-01-01

    With the increasing availability of positioning based on GPS, Wi-Fi, and cellular technologies and the proliferation of mobile devices with GPS, Wi-Fi and cellular connectivity, ubiquitous positioning is becoming a reality. While offerings by companies such as Google, Skyhook, and Spotigo render...... positioning possible in outdoor settings, including urban environments with limited GPS coverage, they remain unable to offer accurate indoor positioning. We will demonstrate a software infrastructure that makes it easy for anybody to build support for accurate Wi-Fi based positioning in buildings. All...... that is needed is a building with Wi-Fi coverage, access to the building, a floor plan of the building, and a Wi-Fi enabled device. Specifically, we will explain the software infrastructure and the steps that must be completed to obtain support for positioning. And we will demonstrate the positioning obtained...

  8. Classical limit of irregular blocks and Mathieu functions

    International Nuclear Information System (INIS)

    Piątek, Marcin; Pietrykowski, Artur R.

    2016-01-01

    The Nekrasov-Shatashvili limit of the N = 2 SU(2) pure gauge (Ω-deformed) super Yang-Mills theory encodes the information about the spectrum of the Mathieu operator. On the other hand, the Mathieu equation emerges entirely within the frame of two-dimensional conformal field theory (2d CFT) as the classical limit of the null vector decoupling equation for some degenerate irregular block. Therefore, it seems to be possible to investigate the spectrum of the Mathieu operator employing the techniques of 2d CFT. To exploit this strategy, a full correspondence between the Mathieu equation and its realization within 2d CFT has to be established. In our previous paper http://dx.doi.org/10.1007/JHEP12(2014)032, we have found that the expression of the Mathieu eigenvalue given in terms of the classical irregular block exactly coincides with the well known weak coupling expansion of this eigenvalue in the case in which the auxiliary parameter is the noninteger Floquet exponent. In the present work we verify that the formula for the corresponding eigenfunction obtained from the irregular block reproduces the so-called Mathieu exponent from which the noninteger order elliptic cosine and sine functions may be constructed. The derivation of the Mathieu equation within the formalism of 2d CFT is based on conjectures concerning the asymptotic behaviour of irregular blocks in the classical limit. A proof of these hypotheses is sketched. Finally, we speculate on how it could be possible to use the methods of 2d CFT in order to get from the irregular block the eigenvalues of the Mathieu operator in other regions of the coupling constant.

  9. Limited agreement of independent RNAi screens for virus-required host genes owes more to false-negative than false-positive factors.

    Directory of Open Access Journals (Sweden)

    Linhui Hao

    Full Text Available Systematic, genome-wide RNA interference (RNAi analysis is a powerful approach to identify gene functions that support or modulate selected biological processes. An emerging challenge shared with some other genome-wide approaches is that independent RNAi studies often show limited agreement in their lists of implicated genes. To better understand this, we analyzed four genome-wide RNAi studies that identified host genes involved in influenza virus replication. These studies collectively identified and validated the roles of 614 cell genes, but pair-wise overlap among the four gene lists was only 3% to 15% (average 6.7%. However, a number of functional categories were overrepresented in multiple studies. The pair-wise overlap of these enriched-category lists was high, ∼19%, implying more agreement among studies than apparent at the gene level. Probing this further, we found that the gene lists implicated by independent studies were highly connected in interacting networks by independent functional measures such as protein-protein interactions, at rates significantly higher than predicted by chance. We also developed a general, model-based approach to gauge the effects of false-positive and false-negative factors and to estimate, from a limited number of studies, the total number of genes involved in a process. For influenza virus replication, this novel statistical approach estimates the total number of cell genes involved to be ∼2,800. This and multiple other aspects of our experimental and computational results imply that, when following good quality control practices, the low overlap between studies is primarily due to false negatives rather than false-positive gene identifications. These results and methods have implications for and applications to multiple forms of genome-wide analysis.

  10. Nuclear Positioning in Muscle Development and Disease

    Directory of Open Access Journals (Sweden)

    Eric eFolker

    2013-12-01

    Full Text Available Muscle disease as a group is characterized by muscle weakness, muscle loss, and impaired muscle function. Although the phenotype is the same, the underlying cellular pathologies, and the molecular causes of these pathologies, are diverse. One common feature of many muscle disorders is the mispositioning of myonuclei. In unaffected individuals myonuclei are spaced throughout the periphery of the muscle fiber such that the distance between nuclei is maximized. However, in diseased muscles, the nuclei are often clustered within the center of the muscle cell. Although this phenotype has been acknowledged for several decades, it is often ignored as a contributor to muscle weakness. Rather, these nuclei are taken only as a sign of muscle repair. Here we review the evidence that mispositioned myonuclei are not merely a symptom of muscle disease but also a cause. Additionally, we review the working models for how myonuclei move from two different perspectives, from that of the nucleus and from that of the cytoskeleton. We further compare and contrast these mechanisms with the mechanisms of nuclear movement in other cell types both to draw general themes for nuclear movement and to identify muscle-specific considerations. Finally, we focus on factors that can be linked to muscle disease and find that genes that regulate myonuclear movement and positioning have been linked to muscular dystrophy. Although the cause-effect relationship is largely speculative, recent data indicate that the position of nuclei should no longer be considered only a means to diagnose muscle disease.

  11. Shoulder surgery in the beach chair position is associated with diminished cerebral autoregulation but no differences in postoperative cognition or brain injury biomarker levels compared with supine positioning: the anesthesia patient safety foundation beach chair study.

    Science.gov (United States)

    Laflam, Andrew; Joshi, Brijen; Brady, Kenneth; Yenokyan, Gayane; Brown, Charles; Everett, Allen; Selnes, Ola; McFarland, Edward; Hogue, Charles W

    2015-01-01

    Although controversial, failing to consider the gravitational effects of head elevation on cerebral perfusion is speculated to increase susceptibility to rare, but devastating, neurologic complications after shoulder surgery in the beach chair position (BCP). We hypothesized that patients in the BCP have diminished cerebral blood flow autoregulation than those who undergo surgery in the lateral decubitus position (LDP). A secondary aim was to examine whether there is a relationship between patient positioning during surgery and postoperative cognition or serum brain injury biomarker levels. Patients undergoing shoulder surgery in the BCP (n = 109) or LDP (n = 109) had mean arterial blood pressure (MAP) and regional cerebral oxygen saturation (rScO2) monitored with near-infrared spectroscopy. A continuous, moving Pearson correlation coefficient was calculated between MAP and rScO2, generating the variable cerebral oximetry index (COx). When MAP is in the autoregulated range, COx approaches zero because there is no correlation between cerebral blood flow and arterial blood pressure. In contrast, when MAP is below the limit of autoregulation, COx is higher because there is a direct relationship between lower arterial blood pressure and lower cerebral blood flow. Thus, diminished autoregulation would be manifest as higher COx. Psychometric testing was performed before surgery and then 7 to 10 days and 4 to 6 weeks after surgery. A composite cognitive outcome was determined as the Z-score. Serum S100β, neuron-specific enolase, and glial fibrillary acidic protein were measured at baseline, after surgery, and on postoperative day 1. After adjusting for age and history of hypertension, COx (P = 0.035) was higher and rScO2 lower (P surgery between the BCP and the LDP groups. There was no difference in serum biomarker levels between the 2 position groups : Compared with patients in the LDP, patients undergoing shoulder surgery in the BCP are more likely to have higher COx

  12. Who Pulls the Trigger? Evidence on Corporate Currency Speculation

    DEFF Research Database (Denmark)

    Aabo, Tom; Hansen, Marianna Andryeyeva; Pantzalis, Christos

    This empirical study of non-financial firms is based on a survey of 186 medium-sized, non-financial Danish firms with operating revenues and/or costs in foreign currency. We find that the involvement of non-finance departments in the management of exchange rate risks has a positive impact...

  13. Preferred partner characteristics in homosexual men in relation to speculated patterns of brain differentiation.

    Science.gov (United States)

    Muscarella, Frank

    2002-08-01

    The current study was designed to test a neurohormonally based theory of sexual orientation and preferred partner characteristics in homosexual men. The theory holds that the brains of homosexual men are masculinized and feminized directing attraction to targets younger and more masculine than self, and the brains of homosexual adolescents are incompletely masculinized and feminized directing attraction to targets older and more masculine than self. Ninety-six homosexual men completed questionnaires that asked them to rate morphological and behavioral characteristics associated with ethologically relevant indicators of masculinity. The participants made ratings for themselves as adolescents and adults, their current partners and idealized partners as adults, and their idealized partners as adolescents. Results of within-subjects multivariate analyses of variance supported most of the hypotheses. Participants as adults rated their idealized partners as more masculine than themselves and their real partners on five measures: height, weight, muscle development, facial hair, and sexuality. As adolescents they indicated a preference for males older and more masculine than self. The participants in adulthood did not show the predicted preference for partners younger than themselves. The increased ratings of sexuality for self from adolescence to adulthood support the contention that some additional masculinization of the brain may occur with aging. The increased ratings of body size for the idealized target from adolescence to adulthood keeps the target more masculine then self across developmental periods. This phenomenon is consistent with the speculated feminization of the brain at both periods and its effects on partner preferences.

  14. The Limits of Exercise Physiology

    DEFF Research Database (Denmark)

    Gabriel, Brendan M; Zierath, Juleen R

    2017-01-01

    Many of the established positive health benefits of exercise have been documented by historical discoveries in the field of exercise physiology. These investigations often assess limits: the limits of performance, or the limits of exercise-induced health benefits. Indeed, several key findings have...... been informed by studying highly trained athletes, in addition to healthy or unhealthy people. Recent progress has been made in regard to skeletal muscle metabolism and personalized exercise regimes. In this perspective, we review some of the historical milestones of exercise physiology, discuss how...

  15. Effects of stomatal development on stomatal conductance and on stomatal limitation of photosynthesis in Syringa oblata and Euonymus japonicus Thunb.

    Science.gov (United States)

    Wu, Bing-Jie; Chow, Wah Soon; Liu, Yu-Jun; Shi, Lei; Jiang, Chuang-Dao

    2014-12-01

    During leaf development, the increase in stomatal conductance cannot meet photosynthetic demand for CO2, thus leading to stomatal limitation of photosynthesis (Ls). Considering the crucial influences of stomatal development on stomatal conductance, we speculated whether stomatal development limits photosynthesis to some extent. To test this hypothesis, stomatal development, stomatal conductance and photosynthesis were carefully studied in both Syringa oblata (normal greening species) and Euonymus japonicus Thunb (delayed greening species). Our results show that the size of stomata increased gradually with leaf expansion, resulting in increased stomatal conductance up to the time of full leaf expansion. During this process, photosynthesis also increased steadily. Compared to that in S. oblata, the development of chloroplasts in E. japonicus Thunb was obviously delayed, leading to a delay in the improvement of photosynthetic capacity. Further analysis revealed that before full leaf expansion, stomatal limitation increased rapidly in both S. oblata and E. japonicus Thunb; after full leaf expansion, stomatal limitation continually increased in E. japonicus Thunb. Accordingly, we suggested that the enhancement of photosynthetic capacity is the main factor leading to stomatal limitation during leaf development but that stomatal development can alleviate stomatal limitation with the increase of photosynthesis by controlling gas exchange. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Organic positive ions in aircraft gas-turbine engine exhaust

    Science.gov (United States)

    Sorokin, Andrey; Arnold, Frank

    Volatile organic compounds (VOCs) represent a significant fraction of atmospheric aerosol. However the role of organic species emitted by aircraft (as a consequence of the incomplete combustion of fuel in the engine) in nucleation of new volatile particles still remains rather speculative and requires a much more detailed analysis of the underlying mechanisms. Measurements in aircraft exhaust plumes have shown the presence of both different non-methane VOCs (e.g. PartEmis project) and numerous organic cluster ions (MPIK-Heidelberg). However the link between detected organic gas-phase species and measured mass spectrum of cluster ions is uncertain. Unfortunately, up to now there are no models describing the thermodynamics of the formation of primary organic cluster ions in the exhaust of aircraft engines. The aim of this work is to present first results of such a model development. The model includes the block of thermodynamic data based on proton affinities and gas basicities of organic molecules and the block of non-equilibrium kinetics of the cluster ions evolution in the exhaust. The model predicts important features of the measured spectrum of positive ions in the exhaust behind aircraft. It is shown that positive ions emitted by aircraft engines into the atmosphere mostly consist of protonated and hydrated organic cluster ions. The developed model may be explored also in aerosol investigations of the background atmosphere as well as in the analysis of the emission of fine aerosol particles by automobiles.

  17. Light limitation of phytoplankton biomass and macronutrient utilization in the Southern Ocean

    International Nuclear Information System (INIS)

    Mitchell, B.G.; Brody, E.A.; Holm-Hansen, O.; McClain, C.; Bishop, J.

    1991-01-01

    The Antarctic Circumpolar Current (ACC) is unique in that it has continually high concentrations of major plant nutrients but low phytoplankton biomass. This enigmatic phenomenon is the focus of significant speculation that trace nutrients, including Fe, may limit phytoplankton crop size. Global climatologies indicate that the ACC is a region with low surface temperatures, weak density stratification, little summertime surface solar irradiance, and strong wind stress. These physical phenomena act to limit growth rates of the phytoplankton community. Using a photo-physiological description of phytoplankton growth in a simple one-dimensional ecosystem model forced by observations or climatologies of mixing depth and surface irradiance, the authors make an evaluation of the potential for massive, nutrient-exhausting, phytoplankton blooms forming in the ACC. The ACC has persistent mixed layers in excess of 50 m. Literature values and model optimization indicate that the minimal aggregate specific loss rate and typical physical conditions of stratification and surface irradiance, the model predicts that phytoplankton in the ACC would not utilize >10% of the available macronutrients. Without a mechanism for increasing the strength of stratification, the authors predict that massive Fe additions to the Southern Ocean would fail to significantly mitigate the atmospheric CO 2 derived from fossil fuel

  18. Why Libertarians Should Reject Positive Rights

    OpenAIRE

    Joshua Katz

    2009-01-01

    Maloberti, in “Why Libertarians Should Accept Positive Rights” argues that, as normally presented, libertarianism entails anarchism. He argues that libertarians should, therefore, accept a limited form of positive rights, which will allow for the creation of a libertarian government. In this paper, it is argued that the entailment of anarchism is not a problem for libertarianism, and that the form of positive rights endorsed by Maloberti is unfounded, ill-defined, and inconsistent with libe...

  19. Ego depletion and positive illusions: does the construction of positivity require regulatory resources?

    Science.gov (United States)

    Fischer, Peter; Greitemeyer, Tobias; Frey, Dieter

    2007-09-01

    Individuals frequently exhibit positive illusions about their own abilities, their possibilities to control their environment, and future expectations. The authors propose that positive illusions require resources of self-control, which is considered to be a limited resource similar to energy or strength. Five studies revealed that people with depleted self-regulatory resources indeed exhibited a less-optimistic sense of their own abilities (Study 1), a lower sense of subjective control (Study 2), and less-optimistic expectations about their future (Study 3). Two further studies shed light on the underlying psychological process: Ego-depleted (compared to nondepleted) individuals generated/retrieved less positive self-relevant attributes (Studies 4 and 5) and reported a lower sense of general self-efficacy (Study 5), which both partially mediated the impact of ego depletion on positive self-views (Study 5).

  20. A randomised controlled trial of flow driver and bubble continuous positive airway pressure in preterm infants in a resource-limited setting.

    Science.gov (United States)

    Mazmanyan, P; Mellor, K; Doré, C J; Modi, N

    2016-01-01

    The variable-flow flow driver (FD; EME) and continuous-flow bubble (Fisher-Paykel) continuous positive airway pressure (CPAP) systems are widely used. As these differ in cost and technical requirements, determining comparative efficacy is important particularly where resources are limited. We performed a randomised, controlled, equivalence trial of CPAP systems. We specified the margin of equivalence as 2 days. We analysed binary variables by logistical regression adjusted for gestation, and log transformed continuous variables by multiple linear regression adjusted for gestation, sex and antenatal steroids. A neonatal unit with no blood gas analyser or surfactant availability and limited X-ray and laboratory facilities Neonates CPAP at delivery followed by randomisation to FD or bubble (B). Primary outcome included total days receiving CPAP; secondary outcomes included days receiving CPAP, supplemental oxygen, ventilation, death, pneumothorax and nasal excoriation. We randomised 125 infants (B 66, FD 59). Differences in infant outcomes on B and FD were not statistically significant. The median (range) for CPAP days for survivors was B 0.8 (0.04 to 17.5), FD 0.5 (0.04 to 5.3). B:FD (95% CI) ratios were CPAP days 1.3 (0.9 to 2.1), CPAP plus supplementary oxygen days 1.2 (0.7 to 1.9). B:FD (95% CI) ORs were death 2.3 (0.2 to 28), ventilation 2.1 (0.5 to 9), nasal excoriation 1.2 (0.2 to 8) and pneumothorax 2.4 (0.2 to 26). In a resource-limited setting we found B CPAP equivalent to FD CPAP in the total number of days receiving CPAP within a margin of 2 days. ISRCTN22578364. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  1. Selection of exception limits for all actinide nuclides based on revised criteria for safe international transport

    International Nuclear Information System (INIS)

    Lavarenne, C.; Rouyer, V.; Sert, G.; Mennerdahl, D.; Dean, C.; Barton, N.; Jean, F.

    2003-01-01

    Since 1998, there have been some speculations about future transport of significant quantities and concentrations of other actinide nuclides than the four currently listed in the regulation for the safe transport of the radioactive material. Therefore, it raised a need to specify exception limits for such actinides. Additionally, the total fissile nuclide mass per consignment of excepted packages was limited in the 1996 edition of the regulations (a conveyance limit is preliminary supported in the 2003 revision). The proposed changes of the rules have to take this new control into account. The European Community (DGTREN) decided to fund a project related to this subject. In order to define credible exception limits, it was necessary to have reasonably accurate data for all actinide nuclides. Then the authors of the study decided to perform calculations with different codes (MONK, MCNP, CRISTAL, SCALE) and different cross-section libraries (JEF2.2, ENDFB, JENDL, etc.). This article presents the work achieved and gives propositions of modification for the IAEA requirements for the Safe Transport of Radioactive Material related to, firstly, the list of the fissile materials, and secondly, the rule to determine the quantities of actinide nuclides that can be excepted from the requirements for the packages containing fissile materials. The participants acknowledge the DGTREN who made this work possible due to its support. (author)

  2. Is relativism the limit of my world?

    OpenAIRE

    Jonathan Elizondo Orozco

    2016-01-01

    In his book Tractatus Logico-Philosophicus, Wittgenstein put ethics among the things that our language cannot grasp. Later, in the Philosophical Investigations he extended the possibilities of meaning, which resulted in some speculations about an alternative way to grasp or to express ethical judgements. If this is possible, then some questions arise: Does this imply a Metaethical Cognitivism? If the conditions of expression in the language have been relativized, does this imply an ethical re...

  3. Quantum limits to center-of-mass measurements

    International Nuclear Information System (INIS)

    Vaughan, Timothy; Drummond, Peter; Leuchs, Gerd

    2007-01-01

    We discuss the issue of measuring the mean position (center of mass) of a group of bosonic or fermionic quantum particles, including particle number fluctuations. We introduce a standard quantum limit for these measurements at ultralow temperatures, and discuss this limit in the context of both photons and ultracold atoms. In the case of non-interacting harmonically trapped fermions, we present evidence that the Pauli exclusion principle has a strongly beneficial effect, giving rise to a 1/N scaling in the position standard deviation--as opposed to a 1/√(N) scaling for bosons. The difference between the actual mean-position fluctuation and this limit is evidence for quantum wave-packet spreading in the center of mass. This macroscopic quantum effect cannot be readily observed for noninteracting particles, due to classical pulse broadening. For this reason, we also study the evolution of photonic and matter-wave solitons, where classical dispersion is suppressed. In the photonic case, we show that the intrinsic quantum diffusion of the mean position can contribute significantly to uncertainties in soliton pulse arrival times. We also discuss ways in which the relatively long lifetimes of attractive bosons in matter-wave solitons may be used to demonstrate quantum interference between massive objects composed of thousands of particles

  4. Biased limiter experiments on text

    International Nuclear Information System (INIS)

    Phillips, P.E.; Wootton, A.J.; Rowan, W.L.; Ritz, C.P.; Rhodes, T.L.; Bengtson, R.D.; Hodge, W.L.; Durst, R.D.; McCool, S.C.; Richards, B.; Gentle, K.W.; Schoch, P.; Forster, J.C.; Hickok, R.L.; Evans, T.E.

    1987-01-01

    Experiments using an electrically biased limiter have been performed on the Texas Experimental Tokamak (TEXT). A small movable limiter is inserted past the main poloidal ring limiter (which is electrically connected to the vacuum vessel) and biased at V Lim with respect to it. The floating potential, plasma potential and shear layer position can be controlled. With vertical strokeV Lim vertical stroke ≥ 50 V the plasma density increases. For V Lim Lim > 0 the results obtained are inconclusive. Variation of V Lim changes the electrostatic turbulence which may explain the observed total flux changes. (orig.)

  5. Microbial ecology of extreme environments: Antarctic dry valley yeasts and growth in substrate limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1981-01-01

    The multiple stresses temperature, moisture, and for chemoheterotrophs, sources of carbon and energy of the Dry Valley Antarctica soils allow at best depauperate communities, low in species diversity and population density. The nature of community structure, the operation of biogeochemical cycles, the evolution and mechanisms of adaptation to this habitat are of interest in informing speculations upon life on other planets as well as in modeling the limits of gene life. Yeasts of the Cryptococcus vishniacil complex (Basidiobiastomycetes) are investigated, as the only known indigenes of the most hostile, lichen free, parts of the Dry Valleys. Methods were developed for isolating these yeasts (methods which do not exclude the recovery of other microbiota). The definition of the complex was refined and the importance of nitrogen sources was established as well as substrate competition in fitness to the Dry Valley habitats.

  6. The Limited Capacity of Sleep-Dependent Memory Consolidation

    Directory of Open Access Journals (Sweden)

    Gordon B Feld

    2016-09-01

    Full Text Available Sleep supports memory consolidation. However, the conceptually important influence of the amount of items encoded in a memory test on this effect has not been investigated. In two experiments, participants (n=101 learned lists of word-pairs varying in length (40, 160, 320 word-pairs in the evening before a night of sleep (sleep group or of sleep deprivation (wake group. After 36 h (including a night allowing recovery sleep retrieval was tested. Compared with wakefulness, post-learning sleep enhanced retention for the 160 word-pair condition (p < 0.01, importantly, this effect completely vanished for the 320 word-pair condition. This result indicates a limited capacity for sleep-dependent memory consolidation, which is consistent with an active system consolidation view on sleep’s role for memory, if it is complemented by processes of active forgetting and/or gist abstraction. Whereas the absolute benefit from sleep should have increased with increasing amounts of successfully encoded items, if sleep only passively protected memory from interference. Moreover, the finding that retention performance was significantly diminished for the 320 word-pair condition compared to the 160 word-pair condition in the sleep group, makes it tempting to speculate that with increasing loads of information encoded during wakefulness, sleep might favour processes of forgetting over consolidation.

  7. Automatic limit switch system for scintillation device and method of operation

    International Nuclear Information System (INIS)

    Brunnett, C.J.; Ioannou, B.N.

    1976-01-01

    A scintillation scanner is described having an automatic limit switch system for setting the limits of travel of the radiation detection device which is carried by a scanning boom. The automatic limit switch system incorporates position responsive circuitry for developing a signal representative of the position of the boom, reference signal circuitry for developing a signal representative of a selected limit of travel of the boom, and comparator circuitry for comparng these signals in order to control the operation of a boom drive and indexing mechanism. (author)

  8. MHSP with position detection capability

    Energy Technology Data Exchange (ETDEWEB)

    Natal da Luz, H. [Physics Dept., University of Aveiro, 3810-193 Aveiro (Portugal); Physics Dept., University of Coimbra, 3004-516 Coimbra (Portugal); Veloso, J.F.C.A. [Physics Dept., University of Aveiro, 3810-193 Aveiro (Portugal) and Physics Dept., University of Coimbra, 3004-516 Coimbra (Portugal)]. E-mail: jveloso@fis.ua.pt; Mendes, N.F.C. [Physics Dept., University of Coimbra, 3004-516 Coimbra (Portugal); Santos, J.M.F. dos [Physics Dept., University of Coimbra, 3004-516 Coimbra (Portugal); Mir, J.A. [CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom)

    2007-04-01

    The first implementation of a position sensitive readout for a Micro Hole and Strip Plate (MHSP) is described and tested. The readout consists on a resistive layer crossing the anodes and connected to a preamplifier on each side. By weighing the charge pulses on both preamplifiers it is possible to determine the interaction point. A 100-200 {omega} resistance layer between consecutive strips was found to be the best compromise between position linearity and energy resolution. Preliminary results using 22.1 keV X-rays present a good linearity between the measured and the actual position with a mean deviation of about 0.15 mm and a position resolution of 1.6 mm full-width at half-maximum (FWHM), being limited by the analogue division electronic circuit. The performance of the MHSP position detector will be presented and discussed for 1D readout.

  9. If psychosis were cancer: a speculative comparison

    Science.gov (United States)

    Boden, Zoë; Newton, Elizabeth

    2017-01-01

    Recently, health policy in the UK has begun to engage with the concept of ‘parity of esteem’ between physical and mental healthcare. This has led one recent initiative to improve service provision for first episode psychosis, which aims to bring it into line with some of the principles underpinning good practice in cancer care. In this paper, we consider some of the metaphorical consequences of likening psychosis to cancer. While we find the comparison unhelpful for clinical purposes, we argue that it can be a helpful lens through which to examine service provision for psychosis in young people. Through this lens, specialist community-based services would appear to compare reasonably well. Inpatient care for young people with psychosis, on the other hand, suffers very badly by comparison with inpatient facilities for teenage cancer care. We note some of the many positive features of inpatient cancer care for young adults, and—drawing upon previous research on inpatient psychiatric care—observe that many of these are usually absent from mental health facilities. We conclude that this metaphor may be a helpful rhetorical device for communicating the lack of ‘parity of esteem’ between mental and physical healthcare. This inequity must be made visible in health policy, in commissioning, and in service provision. PMID:28559369

  10. Fourier-positivity constraints on QCD dipole models

    Directory of Open Access Journals (Sweden)

    Bertrand G. Giraud

    2016-09-01

    Full Text Available Fourier-positivity (F-positivity, i.e. the mathematical property that a function has a positive Fourier transform, can be used as a constraint on the parametrization of QCD dipole-target cross-sections or Wilson line correlators in transverse position space r. They are Bessel transforms of positive transverse momentum dependent gluon distributions. Using mathematical F-positivity constraints on the limit r→0 behavior of the dipole amplitudes, we identify the common origin of the violation of F-positivity for various, however phenomenologically convenient, dipole models. It is due to the behavior r2+ϵ, ϵ>0 softer, even slightly, than color transparency. F-positivity seems thus to conflict with the present dipole formalism when it includes a QCD running coupling constant α(r.

  11. Observation of positional relation between mandibular third molars and the mandibular canal on limited cone beam computed tomography

    International Nuclear Information System (INIS)

    Hashizume, Atsuko; Nakagawa, Yoichi; Ishii, Hisako; Kobayashi, Kaoru

    2004-01-01

    We describe the preoperative use of limited cone beam computed tomography (CT) with a dental CT scanner for the assessment of mandibular third molars before extraction. Cone beam CT provides 42.7-mm-high and 30-mm-wide rectangular solid images, with a resolution of less than 0.2 mm. The positional relationship between the mandibular third molars and the mandibular canal was examined by dental CT. Sixty-eight lower third molars of 62 patients whose teeth were superimposed on the mandibular canal on periapical or panoramic radiographs were studied. Dental CT scans clearly demonstrated the positional relationship between the mandibular canal and the teeth. The mandibular canal was located buccally to the roots of 16 teeth, lingually to the roots of 27 teeth, inferiorly to the roots of 23 teeth, and between the roots of 2 teeth. The presence of bone between the mandibular canal and the teeth was not noted in 7 of 16 buccal cases, 24 of 27 lingual cases, and 10 of 23 inferior cases on dental CT scans, suggesting that the canal was in contact with the teeth. Fifty-nine of the 68 mandibular third molars were surgically removed, and postoperative transient hypoesthesia occurred in 4 patients. Dental CT scans showed no bone between the mandibular canal and the teeth in all 4 patients. Hypoesthesia was not related to the bucco-lingual location of the mandibular canal or to the extent of bone loss between the canal and the teeth. However, hypoesthesia did not occur in patients with bone between the mandibular canal and the teeth. Thus, information on the distance between the canal and teeth on dental CT scans was useful for predicting the risk of inferior alveolar nerve damage. Because of its high resolution and low radiation dose, cone beam CT was useful for examination before mandibular third molar surgery. (author)

  12. Why Libertarians Should Reject Positive Rights

    Directory of Open Access Journals (Sweden)

    Joshua Katz

    2009-01-01

    Full Text Available Maloberti, in “Why Libertarians Should Accept Positive Rights” argues that, as normally presented, libertarianism entails anarchism. He argues that libertarians should, therefore, accept a limited form of positive rights, which will allow for the creation of a libertarian government. In this paper, it is argued that the entailment of anarchism is not a problem for libertarianism, and that the form of positive rights endorsed by Maloberti is unfounded, ill-defined, and inconsistent with libertarian notions of individual freedom. It is further argued that Maloberti’s positive rights, as defined in his paper, cannot withstand the analysis prompted by Austrian value theory.

  13. Provisional thoughts on limitations to the right to procreate ...

    African Journals Online (AJOL)

    ... also had a severe non-intended impact on the social and economic situation in China. It is suggested, therefore, that positive measures (eg proper education and social provision) be considered to limit population growth. KEYWORDS: Limitation of rights; right to procreate; overpopulation; limitation of the right to procreate; ...

  14. High rate behavior and discharge limits in micro-pattern detectors

    International Nuclear Information System (INIS)

    Bressan, A.; Hoch, M.; Pagano, P.; Ropelewski, L.; Sauli, F.; Biagi, S.; Buzulutskov, A.; Gruwe, M.; De Lentdecker, G.; Moermann, D.; Sharma, A.

    1999-01-01

    We present and discuss a set of systematic measurements, carried out with gaseous proportional micro-pattern detectors, in order to assess their maximum gain when irradiated with high-rate soft X-rays and heavily ionizing alpha particles. The inventory of detectors tested includes: micro-strips, micromegas, micro-dot, gas electron multiplier, CAT (compteur a trous), trench (or groove), micro-CAT (or WELL) detectors, as well as systems with two elements of gaseous amplification in cascade. We confirm the general trend of all single-stage detectors to follow Raether's criterion, i.e. a spontaneous transition from avalanche to streamer, followed by a discharge, when the avalanche size reaches a value of a few 10 7 ; a noticeable exception is the micro-dot counter holding more than 10 8 . In multiple structures, where the gain is shared between two devices in cascade, the maximum overall gain under irradiation is increased by at least one order of magnitude; we speculate this to be a consequence of a voltage dependence of Raether's limit, larger for low operating potentials. Our conclusion is that only multiple devices can guarantee a sufficient margin of reliability for operation in harsh LHC running conditions

  15. Onset of mobility limitations in old age: the combined effect of socioeconomic position and social relations

    DEFF Research Database (Denmark)

    Nilsson, Charlotte Juul; Avlund, Kirsten; Lund, Rikke

    2011-01-01

    performed in a study population of 2,839 older men and women from the Danish Intervention Study on Preventive Home Visits. Results: among men low financial assets, living alone or having low social participation significantly increased the odds ratios (OR) for onset of mobility limitations. Among women only...... limitations among both genders, yet the tendencies appeared stronger for males. In particular, men with simultaneous exposure to low financial assets and low social participation had increased odds ratios for onset of mobility limitations, OR = 5.36 (2.51-11.47), compared with the non-exposed. Conclusion...... low financial assets and low social participation significantly increased the ORs for onset of mobility limitations. Analyses with combined exposure variables showed that simultaneous exposure to low financial assets and poor social relations significantly increased the ORs for onset of mobility...

  16. Relationship between job stress, occupational position and job satisfaction using a brief job stress questionnaire (BJSQ).

    Science.gov (United States)

    Kawada, Tomoyuki; Otsuka, Toshiaki

    2011-01-01

    Subjects with higher occupational position are speculated to have higher ability to handle with stress, and they were less affected by job stress. This study focused on the relationship between job satisfaction and three sub-scales of a brief job stress questionnaire (BJSQ) related to workload. This self-administered questionnaire was distributed to 371 employees of a company, and all the workers sent back their responses. Among the 57 items graded on a 4-point Likert-type scale to measure job stressors, psycho-physical complaints, and support for workers, the authors studied the influence of quantitative and qualitative job overload (six items), job control (three items), and support port (six items). The job satisfaction score estimated on a 4-point Likert-type scale was also used in relation to job stress determined using a 15-item scale from the BJSQ based on demand-control-support model. Occupational positions were classified into directors, managers, and general workers, and the content of job was classified into clerical workers, skilled technicians, and unskilled manual workers. All the scales on job stress presented acceptable alpha coefficients reflecting high internal consistency (job demand: 0.855, job control: 0.644, and support: 0.878, respectively). Principal axis factor analysis was conducted, and three factors were extracted; support, job demand and job control. There was a significant difference in the mean score among four groups divided by the job satisfaction level as evaluated by Dunnett's multiple comparison, and members who were dissatisfied with their job showed a high job demand, limited job control, and poor support. The mean score of support for managers were significantly higher (lower support) than that for general workers. The logistic regression analysis revealed that job control and support contributed significantly to job satisfaction. In addition, unskilled manual workers showed significantly higher job dissatisfaction compared

  17. Limited time perspective increases the value of calm.

    Science.gov (United States)

    Jiang, Da; Fung, Helene H; Sims, Tamara; Tsai, Jeanne L; Zhang, Fan

    2016-02-01

    Previous findings indirectly suggest that the more people perceive their time in life as limited, the more they value calm. No study, however, has directly tested this hypothesis. To this end, using a combination of survey, experience sampling, and experimental methods, we examined the relationship between future time perspective and the affective states that people ideally want to feel (i.e., their "ideal affect"). In Study 1, the more people reported a limited time perspective, the more they wanted to feel calm and experience other low-arousal positive states. In Study 2, participants were randomly assigned to a limited time or an expanded time condition. Participants in the limited time condition reported valuing calm and other low arousal positive states more than those in the expanded time condition. We discuss the implications of these findings for broadening our understanding of the factors that shape how people ideally want to feel, and their consequences for decision making. (c) 2016 APA, all rights reserved).

  18. The Limits to Giving Back

    Directory of Open Access Journals (Sweden)

    Jade S. Sasser

    2014-07-01

    Full Text Available In this thematic section, authors consider the limitations on giving back that they faced in field research, or saw others face. For some authors, their attempts at giving back were severely limited by the scope of their projects, or their understandings of local cultures or histories. For others, very specific circumstances and historical interventions of foreigners in certain places can limit how and to what extent a researcher is able to have a reciprocal relationship with the participating community. Some authors, by virtue of their lesser positions of power relative to those that they were studying, simply decided not to give back to those communities. In each article it becomes apparent that how and in what ways people give back is unique (and limited both to their personal values and the contexts in which they do research.

  19. FTU pump limiter

    International Nuclear Information System (INIS)

    Alessandrini, C.; Ciotti, M.; Mattei, A. De; Maddaluno, G.; Mazzitelli, G.

    1989-01-01

    The control of the refuelling and recycling of the plasma is crucial in providing enhanced performances in tokamaks and steady-state operation in future reactors. In this paper, we report details of the design and analysis for the pump limiter to be incorporated into the FTU tokamak. The FTU, presently under commissioning, is a compact high field (B=8T), medium high density, circular cross section machine with small accesses. The dimensions of the equatorial port (width 8 cm) would reduce the length of the entrance throat to a few centimeters, which is unacceptable for efficient particle trapping. We have, therefore, designed a rotating blade of the pump limiter head that, in the working position, extends in the toroidal direction inside the vacuum chamber. (author) 8 refs., 4 figs

  20. Positivity-preserving space-time CE/SE scheme for high speed flows

    KAUST Repository

    Shen, Hua

    2017-03-02

    We develop a space-time conservation element and solution element (CE/SE) scheme using a simple slope limiter to preserve the positivity of the density and pressure in computations of inviscid and viscous high-speed flows. In general, the limiter works with all existing CE/SE schemes. Here, we test the limiter on a central Courant number insensitive (CNI) CE/SE scheme implemented on hybrid unstructured meshes. Numerical examples show that the proposed limiter preserves the positivity of the density and pressure without disrupting the conservation law; it also improves robustness without losing accuracy in solving high-speed flows.

  1. Positivity-preserving space-time CE/SE scheme for high speed flows

    KAUST Repository

    Shen, Hua; Parsani, Matteo

    2017-01-01

    We develop a space-time conservation element and solution element (CE/SE) scheme using a simple slope limiter to preserve the positivity of the density and pressure in computations of inviscid and viscous high-speed flows. In general, the limiter works with all existing CE/SE schemes. Here, we test the limiter on a central Courant number insensitive (CNI) CE/SE scheme implemented on hybrid unstructured meshes. Numerical examples show that the proposed limiter preserves the positivity of the density and pressure without disrupting the conservation law; it also improves robustness without losing accuracy in solving high-speed flows.

  2. Positivity for Convective Semi-discretizations

    KAUST Repository

    Fekete, Imre

    2017-04-19

    We propose a technique for investigating stability properties like positivity and forward invariance of an interval for method-of-lines discretizations, and apply the technique to study positivity preservation for a class of TVD semi-discretizations of 1D scalar hyperbolic conservation laws. This technique is a generalization of the approach suggested in Khalsaraei (J Comput Appl Math 235(1): 137–143, 2010). We give more relaxed conditions on the time-step for positivity preservation for slope-limited semi-discretizations integrated in time with explicit Runge–Kutta methods. We show that the step-size restrictions derived are sharp in a certain sense, and that many higher-order explicit Runge–Kutta methods, including the classical 4th-order method and all non-confluent methods with a negative Butcher coefficient, cannot generally maintain positivity for these semi-discretizations under any positive step size. We also apply the proposed technique to centered finite difference discretizations of scalar hyperbolic and parabolic problems.

  3. Some speculations on a beginning of a causal unified model of relativity, gravitation and quantum mechanics

    International Nuclear Information System (INIS)

    Buonomano, V.; Engel, A.

    1974-10-01

    Some speculations on a causal model that seems to provide a common conceptual foundation for Relativity Gravitation and Quantum Mechanics are presented. The present approach is a unifying of three theories. The first being the repulsive theory of gravitational forces first proposed by Lesage in the eighteenth century. The second of these theories is the Brownian Motion Theory of Quantum Mechanics or Stocastic Mechanics which treats the non-deterministic Nature of Quantum Mechanics as being due to a Brownian motion of all objects. This Brownian motion being caused by the statistical variation in the graviton flux. The above two theories are unified with the Causal Theory of Special Relativity. Within the present context, the time dilations (and other effects) of Relativity are explained by assuming that the rate of a clock is a function of the total number or intensity of gravitons and the average frequency or energy of the gravitons that the clock receives. The Special Theory would then be the special case of the General Theory where the intensity is constant but the average frequency varies. In all the previous it is necessary to assume a particular model of the creation of the universe, namely the Big Bang Theory. This assumption gives us the existence of a preferred reference frame, the frame in which the Big Bang explosion was at rest. The above concepts of graviton distribution and real time dilations become meaningful by assuming the Big Bang Theory along with this preferred frame. An experimental test is proposed

  4. Limit of detection and threshold for positivity of the Centers for Disease Control and Prevention assay for factor VIII inhibitors.

    Science.gov (United States)

    Miller, C H; Boylan, B; Shapiro, A D; Lentz, S R; Wicklund, B M

    2017-10-01

    Essentials Immunologic methods detect factor VIII (FVIII) antibodies in some inhibitor-negative specimens. Specimens were tested by modified Nijmegen-Bethesda assay (NBA) and fluorescence immunoassay. The NBA with preanalytical heat inactivation detects FVIII inhibitors down to 0.2 NBU. IgG 4 frequency validates the established threshold for positivity of ≥ 0.5 NBU for this NBA. Background The Bethesda assay for measurement of factor VIII inhibitors called for quantification of positive inhibitors by using dilutions producing 25-75% residual activity (RA), corresponding to 0.4-2.0 Bethesda units, with the use of 'more sensitive methods' for samples with RA closer to 100% being recommended. The Nijmegen modification (Nijmegen-Bethesda assay [NBA]) changed the reagents used but not these calculations. Some specimens negative by the NBA have been shown to have FVIII antibodies detectable with sensitive immunologic methods. Objective To examine the performance at very low inhibitor titers of the Centers for Disease Control and Prevention (CDC)-modified NBA (CDC-NBA), which includes preanalytic heat inactivation to liberate bound anti-FVIII antibodies. Methods Specimens with known inhibitors were tested with the CDC-NBA. IgG 4 anti-FVIII antibodies were measured by fluorescence immunoassay (FLI). Results Diluted inhibitors showed linearity below 0.4 Nijmegen-Bethesda units (NBU). With four statistical methods, the limit of detection of the CDC-NBA was determined to be 0.2 NBU. IgG 4 anti-FVIII antibodies, which correlate most strongly with functional inhibitors, were present at rates above the background rate of healthy controls in specimens with titers ≥ 0.2 NBU and showed an increase in frequency from 14.3% at 0.4 NBU to 67% at the established threshold for positivity of 0.5 NBU. Conclusions The CDC-NBA can detect inhibitors down to 0.2 NBU. The FLI, which is more sensitive, demonstrates anti-FVIII IgG 4 in some patients with negative (NBA, supporting the need for

  5. Is the benefit of postmastectomy irradiation limited to patients with four or more positive nodes, as recommended in international consensus reports? A subgroup analysis of the DBCG 82 b & c randomized trials

    DEFF Research Database (Denmark)

    Overgaard, Marie; Nielsen, Hanne Melgaard; Overgaard, Jens

    2007-01-01

    % to 10% (p4% (p...BACKGROUND AND AIM: Numerous consensus reports recommend that postmastectomy radiotherapy (RT) in addition to systemic therapy is indicated in high-risk patients with 4+ positive nodes, but not in patients with 1-3 positive nodes. A subgroup analysis of the DBCG 82 b&c trials was performed...... lymph nodes removed (median 7), the present analysis was limited to 1152 node positive patients with 8 or more nodes removed. RESULTS: The overall 15-year survival rate in the subgroup was 39% and 29% (p=0.015) after RT and no RT, respectively. RT reduced the 15-year loco-regional failure rate from 51...

  6. Aetiology and management of malnutrition in HIV-positive children.

    Science.gov (United States)

    Rose, Anna M; Hall, Charles S; Martinez-Alier, Nuria

    2014-06-01

    Worldwide, more than 3 million children are infected with HIV and, without treatment, mortality among these children is extremely high. Both acute and chronic malnutrition are major problems for HIV-positive children living in resource-limited settings. Malnutrition on a background of HIV represents a separate clinical entity, with unique medical and social aetiological factors. Children with HIV have a higher daily calorie requirement than HIV-negative peers and also a higher requirement for micronutrients; furthermore, coinfection and chronic diarrhoea due to HIV enteropathy play a major role in HIV-associated malnutrition. Contributory factors include late presentation to medical services, unavailability of antiretroviral therapy, other issues surrounding healthcare provision and food insecurity in HIV-positive households. Treatment protocols for malnutrition have been greatly improved, yet there remains a discrepancy in mortality between HIV-positive and HIV-negative children. In this review, the aetiology, prevention and treatment of malnutrition in HIV-positive children are examined, with particular focus on resource-limited settings where this problem is most prevalent. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. Limiting currents of overcompensated electron beams

    International Nuclear Information System (INIS)

    Malafaev, V.A.

    1990-01-01

    A possibility of producing recompensated electron beam and increasing its limiting currents in the magnetic field is experimentally investigated. It is shown that such a possibility is realized when the beam is surrounded by a cylindrical net placed into the tube located under the positive potential relative to the net. In this case an increase of limiting current at the expense of increasing the ion life time, takes place. Current, exceeding the Pierce threshold 1.5 times, is obtained

  8. Meningeal Hemangiopericytoma with Intracranial Metastases in an HIV-Positive Male: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Zachary Beatty

    2012-03-01

    Full Text Available Background: Meningeal hemangiopericytoma is a rare, aggressive CNS tumor that tends to invade locally, metastasize, and has a high rate of recurrence. HIV classically increases the risk of 3 AIDS-defining malignancies: Kaposi’s sarcoma, non-Hodgkin’s lymphoma and invasive cervical cancer. More recently, considerable interest has been paid to the link between HIV and a wider range of non-AIDS-defining cancers. An HIV-positive patient with meningeal hemangiopericytoma is described. Case Description: A 36-year-old HIV-positive male presented with worsening headache and ataxia. The patient had experienced similar neurologic symptoms 4 months prior and MRI at that time had showed an extra-axial left cerebellar mass most consistent with benign meningioma. Repeat MRI showed the tumor had increased in size by a factor of greater than 20 in this 4-month period, with 4 small additional foci of similar enhancement. Subtotal resection was performed on the mass and final pathological diagnosis was meningeal hemangiopericytoma. Conclusions: This represents the first reported case of meningeal hemangiopericytoma in an HIV-positive patient. This is also the shortest time to intracranial metastasis ever reported for a meningeal hemangiopericytoma. Although the increased risk in the HIV-positive population of non-AIDS-defining cancers that has been observed in recent years can largely be attributed to cancers with a known viral pathogenesis, it is speculated that HIV infection in this patient may have contributed to the occurrence or unique behavior of this rare tumor.

  9. ["Purified empiricism": Johann Christian Reil's (1759-1813) attempts at a foundation of medicine in relation to its tradition, kantianism, and speculative philosophy].

    Science.gov (United States)

    Steinmann, Michael

    2013-01-01

    Johann Christian Reil's (1759-1813) importance lies in his theoretical approach to medicine. Following Kant in his early work, he attempts to combine medical experience with an underlying conceptual structure. This attempt is directed against both the chaotic empiricism of traditional medicine and speculative theories such as vitalism. The paper starts from his early reflections on the concept of a life force, which he interprets in the way of a non-reductive materialism. In the following, the basic outlines of his Theory of Fever will be shown. The Theory is a systematic attempt at finding a new foundation for diagnosis and therapy on the basis of the concept of fever, which is understood as modification of vital processes. The paper ends with a discussion of his later work, which has remained controversial so far. It shows that the combination of practical empiricism and scientific theory remained rather unstable in this early phase of the development of modern medicine.

  10. Platform Architecture for Decentralized Positioning Systems

    Directory of Open Access Journals (Sweden)

    Zakaria Kasmi

    2017-04-01

    Full Text Available A platform architecture for positioning systems is essential for the realization of a flexible localization system, which interacts with other systems and supports various positioning technologies and algorithms. The decentralized processing of a position enables pushing the application-level knowledge into a mobile station and avoids the communication with a central unit such as a server or a base station. In addition, the calculation of the position on low-cost and resource-constrained devices presents a challenge due to the limited computing, storage capacity, as well as power supply. Therefore, we propose a platform architecture that enables the design of a system with the reusability of the components, extensibility (e.g., with other positioning technologies and interoperability. Furthermore, the position is computed on a low-cost device such as a microcontroller, which simultaneously performs additional tasks such as data collecting or preprocessing based on an operating system. The platform architecture is designed, implemented and evaluated on the basis of two positioning systems: a field strength system and a time of arrival-based positioning system.

  11. Accurate decisions in an uncertain world: collective cognition increases true positives while decreasing false positives.

    Science.gov (United States)

    Wolf, Max; Kurvers, Ralf H J M; Ward, Ashley J W; Krause, Stefan; Krause, Jens

    2013-04-07

    In a wide range of contexts, including predator avoidance, medical decision-making and security screening, decision accuracy is fundamentally constrained by the trade-off between true and false positives. Increased true positives are possible only at the cost of increased false positives; conversely, decreased false positives are associated with decreased true positives. We use an integrated theoretical and experimental approach to show that a group of decision-makers can overcome this basic limitation. Using a mathematical model, we show that a simple quorum decision rule enables individuals in groups to simultaneously increase true positives and decrease false positives. The results from a predator-detection experiment that we performed with humans are in line with these predictions: (i) after observing the choices of the other group members, individuals both increase true positives and decrease false positives, (ii) this effect gets stronger as group size increases, (iii) individuals use a quorum threshold set between the average true- and false-positive rates of the other group members, and (iv) individuals adjust their quorum adaptively to the performance of the group. Our results have broad implications for our understanding of the ecology and evolution of group-living animals and lend themselves for applications in the human domain such as the design of improved screening methods in medical, forensic, security and business applications.

  12. The Speculative Neuroscience of the Future Human Brain

    Directory of Open Access Journals (Sweden)

    Robert A. Dielenberg

    2013-05-01

    Full Text Available The hallmark of our species is our ability to hybridize symbolic thinking with behavioral output. We began with the symmetrical hand axe around 1.7 mya and have progressed, slowly at first, then with greater rapidity, to producing increasingly more complex hybridized products. We now live in the age where our drive to hybridize has pushed us to the brink of a neuroscientific revolution, where for the first time we are in a position to willfully alter the brain and hence, our behavior and evolution. Nootropics, transcranial direct current stimulation (tDCS, transcranial magnetic stimulation (TMS, deep brain stimulation (DBS and invasive brain mind interface (BMI technology are allowing humans to treat previously inaccessible diseases as well as open up potential vistas for cognitive enhancement. In the future, the possibility exists for humans to hybridize with BMIs and mobile architectures. The notion of self is becoming increasingly extended. All of this to say: are we in control of our brains, or are they in control of us?

  13. Electrode and limiter biasing experiments on the tokamak ISTTOK

    International Nuclear Information System (INIS)

    Silva, C.; Figueiredo, H.; Cabral, J.A.C.; Nedzelsky, I.; Varandas, C.A.F.

    2003-01-01

    In this contribution limiter and electrode biasing experiments are compared, in particular in what concerns their effects on the edge plasma parameters. For electrode AC bias a substantial increase (>50%) in the average plasma density is observed with positive voltage, without significant changes in the edge density, leading to steeper profiles. The ratio n e /Hα also increases significantly (>20%), indicating an improvement in gross particle confinement. The plasma potential profile is strongly modified as both the edge E r and its shear increase significantly. For positive limiter bias an increase in the average plasma density and the radiation losses is observed, resulting in almost no modification, or a slight, in particle confinement. Preliminary results of simultaneous electrode and limiter bias experiments show that the control of the plasma potential profile is very limited, since negative voltages do not modify the plasma parameters significantly. (author)

  14. Intrinsic position uncertainty impairs overt search performance.

    Science.gov (United States)

    Semizer, Yelda; Michel, Melchi M

    2017-08-01

    Uncertainty regarding the position of the search target is a fundamental component of visual search. However, due to perceptual limitations of the human visual system, this uncertainty can arise from intrinsic, as well as extrinsic, sources. The current study sought to characterize the role of intrinsic position uncertainty (IPU) in overt visual search and to determine whether it significantly limits human search performance. After completing a preliminary detection experiment to characterize sensitivity as a function of visual field position, observers completed a search task that required localizing a Gabor target within a field of synthetic luminance noise. The search experiment included two clutter conditions designed to modulate the effect of IPU across search displays of varying set size. In the Cluttered condition, the display was tiled uniformly with feature clutter to maximize the effects of IPU. In the Uncluttered condition, the clutter at irrelevant locations was removed to attenuate the effects of IPU. Finally, we derived an IPU-constrained ideal searcher model, limited by the IPU measured in human observers. Ideal searchers were simulated based on the detection sensitivity and fixation sequences measured for individual human observers. The IPU-constrained ideal searcher predicted performance trends similar to those exhibited by the human observers. In the Uncluttered condition, performance decreased steeply as a function of increasing set size. However, in the Cluttered condition, the effect of IPU dominated and performance was approximately constant as a function of set size. Our findings suggest that IPU substantially limits overt search performance, especially in crowded displays.

  15. Convergence Time and Positioning Accuracy Comparison between BDS and GPS Precise Point Positioning

    Directory of Open Access Journals (Sweden)

    ZHANG Xiaohong

    2015-03-01

    Full Text Available BDS/GPS data from MGEX were processed by TriP 2.0 software developed at Wuhan University. Both static and kinematic float PPP are tested by adopting precise satellite orbits and clocks provided by Research Center of GNSS, Wuhan University. The results show that the convergence time of BDS static PPP is about 80min while kinematic PPP is about 100min. For 3h observations, static positioning accuracy of 5 cm and kinematic positioning accuracy of 8 cm in horizontal, about 12 cm in vertical can be achieved. Similar to GPS PPP, precision in east component is worse than north. At present, BDS PPP needs longer convergence time than GPS PPP to reach an absolute positioning accuracy of cm~dm due to the lack of global tracking stations and the limited accuracy of orbit and clock products.

  16. Airborne relay-based regional positioning system.

    Science.gov (United States)

    Lee, Kyuman; Noh, Hongjun; Lim, Jaesung

    2015-05-28

    Ground-based pseudolite systems have some limitations, such as low vertical accuracy, multipath effects and near-far problems. These problems are not significant in airborne-based pseudolite systems. However, the monitoring of pseudolite positions is required because of the mobility of the platforms on which the pseudolites are mounted, and this causes performance degradation. To address these pseudolite system limitations, we propose an airborne relay-based regional positioning system that consists of a master station, reference stations, airborne relays and a user. In the proposed system, navigation signals are generated from the reference stations located on the ground and are relayed via the airborne relays. Unlike in conventional airborne-based systems, the user in the proposed system sequentially estimates both the locations of airborne relays and his/her own position. Therefore, a delay due to monitoring does not occur, and the accuracy is not affected by the movement of airborne relays. We conducted several simulations to evaluate the performance of the proposed system. Based on the simulation results, we demonstrated that the proposed system guarantees a higher accuracy than airborne-based pseudolite systems, and it is feasible despite the existence of clock offsets among reference stations.

  17. Design of precision position adjustable scoop

    International Nuclear Information System (INIS)

    Li Zhili; Zhang Kai; Dong Jinping

    2014-01-01

    In isotopes separation technologies, the centrifuge method has been the most popular technology now. Separation performance of centrifugal machines is greatly influenced by the flow field in the centrifugal machines. And the position of scoops in the centrifuges has a significant influence on the flow field. To obtain a better flow field characteristic and find the best position of scoops in the centrifuges, a position adjustable scoop system was studied. A micro stage and a linear encoder were used in the system to improve the position accuracy of the scoop. Eddy current sensors had been used in a position calibration measurement. The measurement result showed the sensitivity and stability of the position system could meet the performance expectation. But as the driving mean, the steel wire and pulley limit the control precision. On the basis of this scheme, an ultrasonic motor was used as driving mean. Experimental results showed the control accuracy was improved. This scheme laid a foundation to obtain internal flow field parameters of centrifuge and get the optimal feeding tube position. (authors)

  18. Ancrage dynamique: principales applications Dynamic Positioning: Main Applications

    Directory of Open Access Journals (Sweden)

    Fay H.

    2006-11-01

    Full Text Available L'ancrage dynamique est la technique qui a permis à la recherche pétrolière d'étendre ses possibilités bien au-delà des plateaux continentaux, sans limitation de profondeur, pour des opérations difficiles, ou encore dans un environnement océanométéorologique sévère, comme celui de la mer du Nord et des mers froides avec la présence d'icebergs. Cet article correspond à des extraits de l'ouvrage Ancrage dynamique. Technique et applications , à paraître aux Editions Technip. Après un bref rappel historique et un exposé succinct des caractéristiques des systèmes d'ancrage dynamique, les principales réalisations de navires et de plates-formes semi-submersibles équipées d'un ancrage dynamique sont présentées. La précision du maintien en position, ainsi que les limites opérationnelles des supports considérés sont de même exposées. Enfin la conclusion retrace les avantages de ce procédé, dont l'exceptionnel développement s'applique aussi aux domaines scientifiques et militaires, ainsi qu'à d'autres secteurs industriels que celui des hydrocarbures. Dynamic positioning is the technique that has enabled oil exploration to extend its possibilities far beyond continental shelves, without any limitation of water depth, for difficult operations or else in harsh environments such as for the North Sea and arctic zones with the presence of icebergs. This paper consists of extracts from the book Dynamic Positioning. Technique and Applications , to be published by Editions Technip. After a brief historical review and a succinct survey of the characteristics of dynamic positioning systems, the principal realizations of ships and semi-submersible platforms equipped with a dynamic positioning system are described. The accuracy of position holding capability as well as the operational limits of the supports considered are also described. The conclusion reviews the advantages of this technique, whose exceptional development also

  19. Plasma vertical instability in a tokamak with rail limiters

    International Nuclear Information System (INIS)

    Belashob, V.I.; Brevnov, N.N.; Gribov, Yu.V.; Putvinskij, S.V.

    1989-01-01

    An effect of currents between rail limiters on plasma equilibrium in the tokamak is studied theoretically and experimentally. Limiter currents can emerge at fast changes of plasma position along rail limiters for example when compression along major radius takes place and result in additional electrodynamic loadings on to the chamber and limiters. It is shown that at high currents between the limiters, the behaviour of discharge depends on limiter voltage polarity. When the plasma - limiter contact points are asymmetrically located respective to an equatorial plane a radial component of the limiter current emerges. The interaction of the component with the toroidal magnetic field can result in a vertical plasma filament instability. 9 refs.; 10 figs

  20. Exclusion Through Speculation

    NARCIS (Netherlands)

    Argenton, C.; Willems, Bert

    2010-01-01

    Many commodities are traded on both a spot market and a derivative market. We show that an incumbent producer may use financial derivatives to extract rent from a potential entrant. The incumbent can indeed sell insurance to a large buyer to commit himself to compete aggressively in the spot market

  1. Speculative data selfies

    NARCIS (Netherlands)

    van der Vlist, F.; Helmond, A.

    2017-01-01

    This short piece examines Data Selfie, an open-source Chrome browser extension that collects and analyses data about your behaviour on facebook.com. The extension has been developed by DATA X (Hang Do Thi Duc and Regina Flores Mir) and was originally announced in April 2016 as an iPhone app and a

  2. 33 CFR 401.52 - Limit of approach to a bridge.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Limit of approach to a bridge... approach to a bridge. (a) No vessel shall pass the limit of approach sign at any movable bridge until the bridge is in a fully open position and the signal light shows green. (b) No vessel shall pass the limit...

  3. Effects of limiter biasing on the ATF torsatron

    International Nuclear Information System (INIS)

    Uckan, T.; Baylor, L.R.; Bell, J.D.; Bigelow, T.S.; England, A.C.; Harris, J.H.; Isler, R.C.; Jernigan, T.C.; Lyon, J.F.; Ma, C.H.; Mioduszewski, P.K.; Murakami, M.; Rasmussen, D.A.; Wilgen, J.B.; Aceto, S.C.; Zielinski, J.J.

    1992-09-01

    Positive limiter biasing on the currentless Advanced Toroidal Facility (ATF) torsatron produces a significant increase in the particle confinement with no improvement in the energy confinement. Experiments have been carried out in 1-T plasmas with ∼400 kill of electron cyclotron heating ECM. Two rail limiters located at the last closed flux surface (LCFS), one at the top and one at the bottom of the device, are biased at positive and negative potentials with respect to the vessel. When the limiters are positively biased at up to 300 V, the density increases sharply to the ECH cutoff value. At the same time, the H α radiation drops, indicating that the particle confinement improves. When the density is kept constant, the H α radiation is further reduced and there is almost no change in the plasma stored energy. Under these conditions, the density profile becomes peaked and the electric field becomes outward-pointing outside the LCFS and more negative inside the LCFS. In contrast, negative biasing yields some reduction of the density and stored energy at constant gas feed, and the plasma potential profile remains the same. Biasing has almost no effect on the intrinsic impurity levels in the plasma

  4. Plasma position control on Alcator C

    International Nuclear Information System (INIS)

    Pribyl, P.A.

    1981-05-01

    The Alcator C MHD equilibrium is investigated from the standpoint of determining the plasma position. A review of equilibrium theory is presented, indicating that the central flux surfaces of the plasma should be displaced about 1 to 2 cm from the outermost. Further, the plasma should have a slightly noncircular cross-section. A comparison is made between the observed and predicted profiles. Flux loops sensitive to plasma position generate the error signal for the feedback control circuit. This measurement agrees with other position-sensitive diagnostics, such as limiter heating, and centroids of density, soft x-ray, and electron cyclotron emission. A linear model is developed for the position control feedback system, including the vertical field SCR supply, plasma, and feedback electronics. Operation of the control system agrees well with that predicted by the model, with acceptable plasma position being maintained for the duration of the discharge. The feedback control system is in daily use for Alcator C runs

  5. Design, building and test of one prototype and four final position sensor assemblies: Hall effect position sensors

    Science.gov (United States)

    1976-01-01

    This report covers the development of a three channel Hall effect position sensing system for the commutation of a three phase dc torquer motor. The effort consisted of the evaluation, modification and re-packaging of a commercial position sensor and the design of a target configuration unique to this application. The resulting design meets the contract requirements and, furthermore, the test results indicate not only the practicality and versatility of the design, but also that there may be higher limits of resolution and accuracy achievable.

  6. Magnetic shielding of a limiter

    International Nuclear Information System (INIS)

    Brevnov, N.N.; Stepanov, S.B.; Khimchenko, L.N.; Matthews, G.F.; Goodal, D.H.J.

    1991-01-01

    Localization of plasma interaction with material surfaces in a separate chamber, from where the escape of impurities is hardly realized, i.e. application of magnetic divertors or pump limiters, is the main technique for reduction of the impurity content in a plasma. In this case, the production of a divertor configuration requires a considerable power consumption and results in a less effective utilization of the magnetic field volume. Utilization of a pump limiter, for example the ICL-type, under tokamak-reactor conditions would result in the extremely high and forbidden local heat loadings onto the limiter surface. Moreover, the magnetically-shielded pump limiter (MSL) was proposed to combine positive properties of the divertor and the pump limiter. The idea of magnetic shielding is to locate the winding with current inside the limiter head so that the field lines of the resultant magnetic field do not intercept the limiter surface. In this case the plasma flows around the limiter leading edges and penetrates into the space under the limiter. The shielding magnetic field can be directed either counter the toroidal field or counter the poloidal one of a tokamak, dependent on the concrete diagram of the device. Such a limiter has a number of advantages: -opportunity to control over the particle and impurity recycling without practical influence upon the plasma column geometry, - perturbation of a plasma column magnetic configuration from the side of such a limiter is less than that from the side of the divertor coils. The main deficiency is the necessity to locate active windings inside the discharge chamber. (author) 5 refs., 3 figs

  7. Empowerment Amongst Teachers Holding Leadership Positions

    Science.gov (United States)

    Avidov-Ungar, Orit; Friedman, Izhak; Olshtain, Elite

    2014-01-01

    This study used semi-structured in-depth interviews to explore empowerment patterns among teachers who hold leadership positions in school. Our qualitative analysis presents a hierarchical ladder with three types of empowerment amongst these teachers, ranging from limited empowerment through rewarding empowerment to change-enhancing empowerment.…

  8. Evidence for subwavelength imaging with positive refraction

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yun Gui [Temasek Laboratories, National University of Singapore, Singapore 119260 (Singapore); Sahebdivan, Sahar; Tyc, Tomas; Leonhardt, Ulf [School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS (United Kingdom); Ong, C K, E-mail: ulf@st-andrews.ac.uk [Centre for Superconducting and Magnetic Materials, Department of Physics, National University of Singapore, Singapore 117542 (Singapore)

    2011-03-15

    The resolution of lenses is normally limited by the wave nature of light. Imaging with perfect resolution was believed to rely on negative refraction, but here we present experimental evidence for subwavelength imaging with positive refraction.

  9. Evidence for subwavelength imaging with positive refraction

    International Nuclear Information System (INIS)

    Ma, Yun Gui; Sahebdivan, Sahar; Tyc, Tomas; Leonhardt, Ulf; Ong, C K

    2011-01-01

    The resolution of lenses is normally limited by the wave nature of light. Imaging with perfect resolution was believed to rely on negative refraction, but here we present experimental evidence for subwavelength imaging with positive refraction.

  10. Emissive limiter bias experiment for improved confinement of tokamaks

    International Nuclear Information System (INIS)

    Choe, W.; Ono, M.; Darrow, D.S.; Pribyl, P.A.; Liberati, J.R.; Taylor, R.J.

    1992-01-01

    Experiments have been performed in Ohmic discharges of the UCLA CCT tokamak with a LaB 6 biased limiter, capable of emitting energetic electrons as a technique to improve confinement in tokamaks. To study the effects of emitted electrons, the limiter position, bias voltage, and plasma position were varied. The results have shown that the plasma positioning with respect to the emissive limiter plays an important role in obtaining H-mode plasmas. The emissive cathode must be located close to the last closed flux surface in order to charge up the plasma. As the cathode is moved closer to the wall, the positioning of the plasma becomes more critical since the plasma can easily detach from the cathode and reattach to the wall, resulting in the termination of H-mode. The emissive capability appears to be important for operating at lower bias voltage and reducing impurity levels in the plasma. With a heated cathode, transition to H-mode was observed for V bias ≤ 50 V and I inj ≥ 30 A. At a lower cathode heater current, a higher bias voltage is required for the transition. Moreover, with a lower cathode heater current, the time delay for inducing H-mode becomes longer, which can be attributed to the required time for the self-heating of the cathode to reach the emissive temperature. From this result, we conclude that the capacity for emission can significantly improve the performance of limiter biasing for inducing H-mode transition. With L-mode plasmas, the injection current flowing out of the cathode was generally higher than 100 A

  11. Case-positive versus case-negative designs for low-rate lithium thionyl chloride cells

    Science.gov (United States)

    Mahy, T. X.

    1982-03-01

    Case polarity design choices are discussed. Two examples of case-negative designs are presented. One battery is thionyl chloride limited and the other is lithium limited. The case-positive design is thionyl chloride limited. It is found that the case-positive/case-negative design consideration does not seem to have much bearing on storage. However, during low rate discharge, the case-negative cells show a steadily decreasing capacity as you go to lower and lower rates.

  12. Profitability of Technical Currency Speculation. The Case of Yen-Dollar Trading 1976-2007

    OpenAIRE

    Schulmeister, Stephan

    2008-01-01

    The paper investigates the profitability of 1,024 moving average and momentum models and their components in the yen-dollar market. It turns out that all models would have been profitable between 1976 and 2007. The models produce more single losses than single profits. At the same time, the size of the single profits is on average much higher than the size of single losses because profitable positions last two to six times longer than unprofitable positions. Hence, the profitability of techni...

  13. The NASA competitive placement plan for positions GS-15 and below (including trades and labor positions)

    Science.gov (United States)

    1993-01-01

    This plan provides the framework for selection based on merit from among the best qualified candidates available. Selections will be made without regard to political, religious, or labor organization affiliation or nonaffiliation, marital status, race, color, sex, national origin, nondisqualifying disability, or age. This plan does not guarantee promotion but rather ensures that all qualified available candidates receive fair and equitable consideration for positions filled under these competitive procedures. Announcing a vacancy under this plan is only one method of locating applicants for a position and can be used in conjunction with other methods. Subject to applicable law and regulation, selection of an individual to fill a position is the decision of management, as is the decision as to the method(s) to be used in identifying candidates. This plan is applicable to all NASA Installations. It covers all positions in the competitive service at (and below) the GS/GM-15 level (including all trades and labor positions), except positions in the Office of the Inspector General. The requirements herein are not intended to, nor should they be construed to limit in any way, the independent personnel authority of the Inspector General under the Inspector General Act, as Amended.

  14. Pharmacological Management of Elderly Patients with Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome: Room for Speculation?

    Science.gov (United States)

    Castiglia, Daniela; Battaglia, Salvatore; Benfante, Alida; Sorino, Claudio; Scichilone, Nicola

    2016-06-01

    Asthma and chronic obstructive pulmonary disease (COPD) are two distinct diseases that share a condition of chronic inflammation of the airways and bronchial obstruction. In clinical settings, it is not rare to come across patients who present with clinical and functional features of both diseases, posing a diagnostic dilemma. The overlap condition has been termed asthma-COPD overlap syndrome (ACOS), and mainly occurs in individuals with long-standing asthma, especially if they are also current or former smokers. Patients with ACOS have poorer health-related quality of life and a higher exacerbation rate than subjects with asthma or COPD alone. Whether ACOS is a distinct nosological entity with genetic variants or rather a condition of concomitant diseases that overlap is still a matter of debate. However, there is no doubt that extended life expectancy has increased the prevalence of asthma and COPD in older ages, and thus the probability that overlap conditions occur in clinical settings. In addition, age-associated changes of the lung create the basis for the two entities to converge on the same subject. ACOS patients may benefit from a stepwise treatment similar to that of asthma and COPD; however, the proposed therapeutic algorithms are only speculative and extrapolated from studies that are not representative of the ACOS population. Inhaled corticosteroids are the mainstay of therapy, and always in conjunction with long-acting bronchodilators. The potential heterogeneity of the overlap syndrome in terms of inflammatory features (T helper-1 vs. T helper-2 pathways) may be responsible for the different responses to treatments. The interaction between respiratory drugs and concomitant diseases should be carefully evaluated. Similarly, the effect of non-respiratory drugs, such as aspirin, statins, and β-blockers, on lung function needs to be properly assessed.

  15. Noncommuting limits of oscillator wave functions

    International Nuclear Information System (INIS)

    Daboul, J.; Pogosyan, G. S.; Wolf, K. B.

    2007-01-01

    Quantum harmonic oscillators with spring constants k > 0 plus constant forces f exhibit rescaled and displaced Hermite-Gaussian wave functions, and discrete, lower bound spectra. We examine their limits when (k, f) → (0, 0) along two different paths. When f → 0 and then k → 0, the contraction is standard: the system becomes free with a double continuous, positive spectrum, and the wave functions limit to plane waves of definite parity. On the other hand, when k → 0 first, the contraction path passes through the free-fall system, with a continuous, nondegenerate, unbounded spectrum and displaced Airy wave functions, while parity is lost. The subsequent f → 0 limit of the nonstandard path shows the dc hysteresis phenomenon of noncommuting contractions: the lost parity reappears as an infinitely oscillating superposition of the two limiting solutions that are related by the symmetry

  16. The Limited Test Ban Treaty

    International Nuclear Information System (INIS)

    Loeb, B.S.

    1991-01-01

    This paper discusses the Limited Test Ban Treaty which came at the end of nearly five years of frustrated efforts to obtain a comprehensive test ban. Negotiations toward that end had begun in October 1958. At the same time a voluntary, informal moratorium on tests was initiated. The negotiations soon stalled over the Soviet Union's resistance to internationally supervised inspections on its soil. In April 1959 a phased ban that was to be limited at first to atmospheric tests conducted below an altitude of 50 kilometers. Such tests were thought to be easily verifiable. The Soviets rejected this idea and continued to insist that a complete test ban need not require numerous inspections. The two sides nevertheless appeared to be nearing agreement on a treaty to ban all but relatively small underground tests when, in May 1960, an U.S. U-2 reconnaissance plane was shot down over Soviet territory. After a thorough review of the U.S. position, the Kennedy administration proposed in April 1961 a draft treaty that made several concessions toward the Soviet position. Nevertheless, the Soviets, still disagreeing with the provisions for verification and with the makeup of the control organization, rejected it

  17. Perioperative Desensitization Improves Outcomes Among Crossmatch Positive Recipients of Deceased Donor Renal Transplants.

    Science.gov (United States)

    Sharma, Amit; King, Anne; Kumar, Dhiren; Behnke, Martha; McDougan, Felecia; Kimball, Pamela M

    2016-06-01

    Graft failure due to chronic rejection is greater among renal transplant patients with donor-specific antibody (DSA) than among DSA-free patients. For patients dependent on deceased donor transplantation, preoperative desensitization to eliminate DSAs may be impractical. We speculated that perioperative desensitization might eliminate preexisting DSAs and prevent de novo DSAs and improve graft outcomes. We report that brief perioperative desensitization using either intravenous immunoglobulin (IVIG) or plasmapheresis/IVIG (PP/IVIG) treatment improves clinical outcomes among patients with positive crossmatches. Immediately following deceased donor transplantation, 235 renal recipients were assigned points for PRA and flow crossmatches (FCXM): delayed graft function (DGF) ≤ 1 point received standard therapy; 2 points received high-dose IVIG; and ≥3 points received PP/IVIG. The DSAs were serially monitored by single antigen bead luminex for 1 year. Five-year clinical outcomes were determined from the chart review. All desensitized patients had preoperatively positive FCXM with DSA. Rejection was more common (P desensitized than nonsensitized groups. However, overall graft survivals were similar between the groups (P = not significant) and superior to historic untreated patients (P 90% in all desensitizated patients with DSA elimination as well as PP/IVIG patients with residual DSA. In contrast, IVIG patients with persistent DSA had poorer graft survival (45%, P desensitization improved overall graft survival of sensitized patients compared to historic untreated patients. Plasmapheresis/IVIG had greater impact on DSA eradication and graft survival than IVIG alone. © 2016, NATCO.

  18. Submicron position-sensitive detector

    Energy Technology Data Exchange (ETDEWEB)

    Pugatch, V M; Rosenfeld, A B; Litovchenko, P G; Barabash, L I; Nemets, O F; Pavlenko, Yu N; Vasiliev, Yu O [Ukrainian Academy of Sciences, Kiev (Ukraine). Inst. for Nuclear Research

    1992-08-01

    A method has been developed to measure precisely the coordinates of charged particles incident between adjacent strips of a strip detector. The position sensitivity of an inter-strip gap has been studied by means of a pulsed laser beam and irradiation by [alpha]-particles of a [sup 226]Ra-source. The capacitive division of charge generated by the incident particle depends on the position of its track. Its coordinates were determined by two-dimensional amplitude analysis of the charges collected by neighbouring strips. This method of coordinate determination applied to studies of spatial and energy distributions of electromagnetic as well as charged particle beams (including radioactive ion beams) of low intensity could provide the highest level of the precision limited by the track dimensions of charged particles, i.e. percents of a micrometer. (orig.).

  19. Photon beam position monitor

    Science.gov (United States)

    Kuzay, Tuncer M.; Shu, Deming

    1995-01-01

    A photon beam position monitor for use in the front end of a beamline of a high heat flux and high energy photon source such as a synchrotron radiation storage ring detects and measures the position and, when a pair of such monitors are used in tandem, the slope of a photon beam emanating from an insertion device such as a wiggler or an undulator inserted in the straight sections of the ring. The photon beam position monitor includes a plurality of spaced blades for precisely locating the photon beam, with each blade comprised of chemical vapor deposition (CVD) diamond with an outer metal coating of a photon sensitive metal such as tungsten, molybdenum, etc., which combination emits electrons when a high energy photon beam is incident upon the blade. Two such monitors are contemplated for use in the front end of the beamline, with the two monitors having vertically and horizontally offset detector blades to avoid blade "shadowing". Provision is made for aligning the detector blades with the photon beam and limiting detector blade temperature during operation.

  20. Emergent classicality via commuting position and momentum operators

    Energy Technology Data Exchange (ETDEWEB)

    Halliwell, J J, E-mail: j.halliwell@ic.ac.u [Blackett Laboratory, Imperial College, London SW7 2BZ (United Kingdom)

    2009-06-01

    Any account of the emergence of classicality from quantum theory must address the fact that the quantum operators representing positions and momenta do not commute, whereas their classical counterparts suffer no such restrictions. To address this, we revive an old idea of von Neumann, and seek a pair of commuting operators X, P which are, in a specific sense, 'close' to the canonical non-commuting position and momentum operators, x,p. The construction of such operators is related to the problem of finding complete sets of orthonormal phase space localized states, a problem severely limited by the Balian-Low theorem. Here these limitations are avoided by restricting attention to situations in which the density matrix is reasonably decohered (i.e., spread out in phase space).

  1. Usefulness and limits of ultrasound guided hook-wire positioning for localisation of soft tissue lesions prior to surgery

    International Nuclear Information System (INIS)

    Trenaghi, Alberto; Dal Bosco, Chiara; Talenti, Enrico; Rubaltelli, Enrico; Borsato, Simonetta; Rossi, Carlo Riccardo; Lumachi, Franco

    2005-01-01

    Purpose. The aim of our study was to assess the usefulness of positioning metal wires under ultrasound guidance for localising soft tissue lesions in the preoperative phase. Materials and methods. We studied superficial soft-tissue lesions in 12 patients, using hooked mammographic wires of different lengths. One patient had a multifocal growth of disease which required a double localisation procedure. Correct positioning of the wire was confirmed by ultrasonography. All patients underwent surgery within five hours of hook-wire positioning. Results. Correct wire position was confirmed at surgery in 12 out of 13 procedures. In one case the hook-wire reached the margin of the lesion. In all cases, the preoperative localisation procedure facilitated identification and resection of the masses. Conclusions. In our experience, the main indications for hook-wire positioning before surgery are: marking of small lesions, localisation of lesions in anatomic areas structurally subverted by previous surgery and consequently difficult to detect, guidance for surgical sectioning in order to safeguard the noble structures dose to the lesions [it

  2. The microbiological diagnosis of tuberculosis in a resource - limited ...

    African Journals Online (AJOL)

    The objective of this study is to audit the processes for the microbiological diagnosis of tuberculosis (TB) in our resource-limited setting. A total of 694 specimens were received from 333 patients. 129 (38.7%) of these patients were positive for TB. 78 (60.5%) were positive on AFB microscopy alone, 13 (10.0%) on culture ...

  3. Physical limits of feedback noise-suppression in biological networks

    International Nuclear Information System (INIS)

    Zhang, Jiajun; Yuan, Zhanjiang; Zhou, Tianshou

    2009-01-01

    Feedback is a ubiquitous control mechanism of biological networks, and has also been identified in a variety of regulatory systems and organisms. It has been shown that, for a given gain and with negligible intrinsic noise, negative feedback impairs noise buffering whereas positive feedback enhances noise buffering. We further investigate the influence of negative and positive feedback on noise in output signals by considering both intrinsic and extrinsic noise as well as operator noise. We find that, while maintaining the system sensitivity, either there exists a minimum of the output noise intensity corresponding to a biologically feasible feedback strength, or the output noise intensity is a monotonic function of feedback strength bounded by both biological and dynamical constraints. In both cases, feedback noise-suppression is physically limited. In other words, noise suppressed by negative or positive feedback cannot be reduced without limitation even in the case of slow transcription

  4. Evidence for subwavelength imaging with positive refraction

    OpenAIRE

    Ma, Yun Gui; Sahebdivan, Sahar; Ong, C. K.; Tyc, Tomas; Leonhardt, Ulf

    2011-01-01

    The resolution of lenses is normally limited by the wave nature of light. Imaging with perfect resolution was believed to rely on negative refraction, but here we present experimental evidence for subwavelength imaging with positive refraction. Publisher PDF Peer reviewed

  5. Fundamental limits on beam stability at the Advanced Photon Source

    International Nuclear Information System (INIS)

    Decker, G. A.

    1998-01-01

    Orbit correction is now routinely performed at the few-micron level in the Advanced Photon Source (APS) storage ring. Three diagnostics are presently in use to measure and control both AC and DC orbit motions: broad-band turn-by-turn rf beam position monitors (BPMs), narrow-band switched heterodyne receivers, and photoemission-style x-ray beam position monitors. Each type of diagnostic has its own set of systematic error effects that place limits on the ultimate pointing stability of x-ray beams supplied to users at the APS. Limiting sources of beam motion at present are magnet power supply noise, girder vibration, and thermal timescale vacuum chamber and girder motion. This paper will investigate the present limitations on orbit correction, and will delve into the upgrades necessary to achieve true sub-micron beam stability

  6. Evaluation of high yielding soybean germplasm under water limitation.

    Science.gov (United States)

    Prince, Silvas J; Murphy, Mackensie; Mutava, Raymond N; Zhang, Zhengzhi; Nguyen, Na; Kim, Yoon Ha; Pathan, Safiullah M; Shannon, Grover J; Valliyodan, Babu; Nguyen, Henry T

    2016-05-01

    Limited information is available for soybean root traits and their plasticity under drought stress. To date, no studies have focused on examining diverse soybean germplasm for regulation of shoot and root response under water limited conditions across varying soil types. In this study, 17 genetically diverse soybean germplasm lines were selected to study root response to water limited conditions in clay (trial 1) and sandy soil (trial 2) in two target environments. Physiological data on shoot traits was measured at multiple crop stages ranging from early vegetative to pod filling. The phenotypic root traits, and biomass accumulation data are collected at pod filling stage. In trial 1, the number of lateral roots and forks were positively correlated with plot yield under water limitation and in trial 2, lateral root thickness was positively correlated with the hill plot yield. Plant Introduction (PI) 578477A and 088444 were found to have higher later root number and forks in clay soil with higher yield under water limitation. In sandy soil, PI458020 was found to have a thicker lateral root system and higher yield under water limitation. The genotypes identified in this study could be used to enhance drought tolerance of elite soybean cultivars through improved root traits specific to target environments. © 2015 Institute of Botany, Chinese Academy of Sciences.

  7. A New Algorithm for Determining Ultimate Pit Limits Based on Network Optimization

    Directory of Open Access Journals (Sweden)

    Ali Asghar Khodayari

    2013-12-01

    Full Text Available One of the main concerns of the mining industry is to determine ultimate pit limits. Final pit is a collection of blocks, which can be removed with maximum profit while following restrictions on the slope of the mine’s walls. The size, location and final shape of an open-pit are very important in designing the location of waste dumps, stockpiles, processing plants, access roads and other surface facilities as well as in developing a production program. There are numerous methods for designing ultimate pit limits. Some of these methods, such as floating cone algorithm, are heuristic and do not guarantee to generate optimum pit limits. Other methods, like Lerchs–Grossmann algorithm, are rigorous and always generate the true optimum pit limits. In this paper, a new rigorous algorithm is introduced. The main logic in this method is that only positive blocks, which can pay costs of their overlying non-positive blocks, are able to appear in the final pit. Those costs may be paid either by positive block itself or jointly with other positive blocks, which have the same overlying negative blocks. This logic is formulated using a network model as a Linear Programming (LP problem. This algorithm can be applied to two- and three-dimension block models. Since there are many commercial programs available for solving LP problems, pit limits in large block models can be determined easily by using this method.

  8. Low-rank extremal positive-partial-transpose states and unextendible product bases

    International Nuclear Information System (INIS)

    Leinaas, Jon Magne; Sollid, Per Oyvind; Myrheim, Jan

    2010-01-01

    It is known how to construct, in a bipartite quantum system, a unique low-rank entangled mixed state with positive partial transpose (a PPT state) from an unextendible product basis (UPB), defined as an unextendible set of orthogonal product vectors. We point out that a state constructed in this way belongs to a continuous family of entangled PPT states of the same rank, all related by nonsingular unitary or nonunitary product transformations. The characteristic property of a state ρ in such a family is that its kernel Ker ρ has a generalized UPB, a basis of product vectors, not necessarily orthogonal, with no product vector in Im ρ, the orthogonal complement of Ker ρ. The generalized UPB in Ker ρ has the special property that it can be transformed to orthogonal form by a product transformation. In the case of a system of dimension 3x3, we give a complete parametrization of orthogonal UPBs. This is then a parametrization of families of rank 4 entangled (and extremal) PPT states, and we present strong numerical evidence that it is a complete classification of such states. We speculate that the lowest rank entangled and extremal PPT states also in higher dimensions are related to generalized, nonorthogonal UPBs in similar ways.

  9. Confinement and gas fueling in LHD limiter discharges

    International Nuclear Information System (INIS)

    Nishimura, K.; Kawahata, K.; Narihara, K.; Morisaki, T.; Masuzaki, S.; Sakakibara, S.; Tanaka, K.

    2003-01-01

    Plasma discharges in the Large Helical Device are normally open helical divertor discharges. To compare limiter discharges with open divertor discharges and to examine the role of the peripheral region, a radial movable limiter, whose head was made of carbon with high heat conductivity, was inserted into the plasma from the high field side (near the helical coil). The electron temperature was bounded well by the limiter. A high temperature gradient at the edge region was observed in both open divertor and limiter discharges. Formation of such a high temperature gradient led to good energy confinement even in the limiter discharges and an enhancement factor of 1.1±0.3 for International Stellarator Scaling 95 (ISS95) scaling was observed at every limiter position (0.75 ax =3.75 m prevents gas fueling by puffing

  10. Quantity and quality limit detritivore growth: mechanisms revealed by ecological stoichiometry and co-limitation theory.

    Science.gov (United States)

    Halvorson, Halvor M; Sperfeld, Erik; Evans-White, Michelle A

    2017-12-01

    Resource quantity and quality are fundamental bottom-up constraints on consumers. Best understood in autotroph-based systems, co-occurrence of these constraints may be common but remains poorly studied in detrital-based systems. Here, we used a laboratory growth experiment to test limitation of the detritivorous caddisfly larvae Pycnopsyche lepida across a concurrent gradient of oak litter quantity (food supply) and quality (phosphorus : carbon [P:C ratios]). Growth increased simultaneously with quantity and quality, indicating co-limitation across the resource gradients. We merged approaches of ecological stoichiometry and co-limitation theory, showing how co-limitation reflected shifts in C and P acquisition throughout homeostatic regulation. Increased growth was best explained by elevated consumption rates and improved P assimilation, which both increased with elevated quantity and quality. Notably, C assimilation efficiencies remained unchanged and achieved maximum 18% at low quantity despite pronounced C limitation. Detrital C recalcitrance and substantive post-assimilatory C losses probably set a minimum quantity threshold to achieve positive C balance. Above this threshold, greater quality enhanced larval growth probably by improving P assimilation toward P-intensive growth. We suggest this interplay of C and P acquisition contributes to detritivore co-limitation, highlighting quantity and quality as potential simultaneous bottom-up controls in detrital-based ecosystems, including under anthropogenic change like nutrient enrichment. © 2017 by the Ecological Society of America.

  11. Selection of exception limits for all actinide nuclides based on revised criteria for safe international transport and including storage delay

    International Nuclear Information System (INIS)

    Lavarenne, C.; Rouyer, V.; Mennerdahl, D.; Dean, C.; Barton, N.; Jean, F.

    2004-01-01

    Since 1998, there have been some speculations about future transport of significant quantities and concentrations of other actinide nuclides than the four currently listed in the regulation for the safe transport of the radioactive material. Therefore, it raised a need to specify exception limits for such actinides. In order to define credible exception limits, it was necessary to have reasonably accurate data for all actinide nuclides. Then the DGTREN/participants decided to perform calculations with different codes (MONK, MCNP, CRISTAL and SCALE) and different cross-section libraries (JEF2.2, ENDFB, etc.). The parameters of interest (such as k-infinite, critical masses) were determined. This article presents the work achieved and the questions raised, e.g. related to the effect of the radioactive decay of the isotopes on the criticality risks. It also points out the need for an evolution of the regulation of the safe transport of radioactive materials and gives a proposition of modification for the IAEA requirements related to, firstly, the list of the fissile materials, secondly, the rule to determine the quantities of actinide nuclides that can be excepted from the requirements for the packages containing fissile materials

  12. The effect of laterally positioned flap-revised technique and 24% ethylenediaminetetraacetic acid root conditioning on root coverage: A case report

    Directory of Open Access Journals (Sweden)

    Jagmohan Singh

    2014-07-01

    Full Text Available Complete root coverage is considered the true goal of treatment of gingival recession defects because only complete coverage assures recovery from the hypersensitivity and esthetic defects associated with recession areas. Previous studies have shown that the laterally positioned flap (LPF technique or root surface biomodification yields a higher percentage of complete root coverage upon gingival recession treatment. This article highlights the use of the laterally positioned pedicle flap-revised technique (LPFRT as a modification of the LPF technique, along with 24% EDTA gel as a root surface biomodification agent, in the management of localized gingival recession defects. Clinical examination revealed a Miller class II recession defect on the buccal aspect of the lower right central incisor, as well as the presence of aberrant frenum pull adjacent to the recession defect. The LPFRT, together with 24% EDTA gel, was speculated to cover the gingival recession defect. The frenectomy, along with periosteal fenestration, was planned simultaneously with LPFRT. After 6 months of therapy, the clinical condition was stable with complete root coverage and satisfactory healing of the gingival tissues at both the donor and recipient sites with no signs of inflammation.

  13. Code as Code: Speculations on Diversity, Inequity, and Digital Women

    Directory of Open Access Journals (Sweden)

    Sharon L. Comstock

    2015-04-01

    Full Text Available All technologies are social. Taking this socio-technological position becomes less a political stance as a necessity when considering the lived experience of digital inequity, divides, and –isms as they are encountered in every-day library work spheres. Personal experience as women and women of color in our respective technological and leadership communities provides both fore- and background to explore the private-public lines delineating definitions of “diversity”, “inequity”, and digital literacies in library practice. We suggest that by not probing these definitions at the most personal level of lived experience, we in the LIS and technology professions will remain well-intentioned, but ineffective, in genuine inclusion.

  14. Ventilator-associated pneumonia: role of positioning.

    Science.gov (United States)

    Li Bassi, Gianluigi; Torres, Antoni

    2011-02-01

    Ventilator-associated pneumonia (VAP) is a lung infection commonly acquired following tracheal intubation. This review assesses the role of the supine semirecumbent and the prone position as VAP preventive strategies and calls attention for further investigation on novel body positions that could potentially reduce risks of VAP. The most recent studies on the semirecumbent position failed to achieve an orientation of the head of the bed higher than 30° and did not corroborate any benefit of the semirecumbent position on VAP, as reported in earlier studies. To date, there is clear evidence that the supine horizontal body position increases risks of pulmonary aspiration and VAP, particularly when patients are enterally fed. Laboratory reports are emphasizing the importance of an endotracheal tube-oropharynx-trachea axis below horizontal to avoid VAP. The prone position potentially increases drainage of oropharyngeal and airways secretions and recent evidence is supporting its beneficial effects. However, several associated adverse effects preclude its regular use as a VAP preventive strategy for patients other than those with acute respiratory distress syndrome. Body position greatly affects several pathogenetic mechanisms of VAP. The current evidence recommends avoidance of supine horizontal position in order to prevent aspiration of colonized gastric contents. The semirecumbent position has proven benefits and should be routinely used but there is still limited evidence to recommend the lowest orientation of the bed at which the patient can be safely maintained. Results from pioneering laboratory investigation call attention to new possible positions, that is lateral Trendelenburg position, aimed to avoid pulmonary aspiration and to enhance mucus clearance in intubated patients.

  15. On the effect of ionospheric delay on geodetic relative GPS positioning

    NARCIS (Netherlands)

    Georgiadou, P.Y.; Kleusberg, A.

    1988-01-01

    Uncorrected ionospheric delay is one of the factors limiting the accuracy in geodetic relative positioning with single frequency Global Positioning System (GPS) carrier phase observations. Dual frequency measurements can be combined to eliminate the ionospheric delay in the observations. A

  16. Constitutional and legal protection for life support limitation in India

    Directory of Open Access Journals (Sweden)

    R K Mani

    2015-01-01

    Full Text Available Appropriate treatment limitations towards the end of life to reduce unwanted burdens require ethical clarity that is supported by appropriate legislation. The lack of knowledge of enabling legal provisions, physicians feel vulnerable to legal misinterpretation of treatment limiting decisions. In India the lack of societal awareness, inadequate exploration of the gray areas of bio-ethics and unambiguous legal position relating to terminal illness have resulted in poor quality end of life care. Much of the perceived vulnerability by the physician is attributable to insufficient knowledge and understanding of existing constitutional and legal position in India. While we await informed legal and legislative opinion, this paper highlights possible legal liabilities arising from treatment limitation decisions with available defense. It is hoped that such clarity would lead to more confident ethical decisions and improved end of life care for patients.

  17. Positive selection on the nonhomologous end-joining factor Cernunnos-XLF in the human lineage

    Directory of Open Access Journals (Sweden)

    Jurka Jerzy

    2006-06-01

    Full Text Available Abstract Background Cernunnos-XLF is a nonhomologous end-joining factor that is mutated in patients with a rare immunodeficiency with microcephaly. Several other microcephaly-associated genes such as ASPM and microcephalin experienced recent adaptive evolution apparently linked to brain size expansion in humans. In this study we investigated whether Cernunnos-XLF experienced similar positive selection during human evolution. Results We obtained or reconstructed full-length coding sequences of chimpanzee, rhesus macaque, canine, and bovine Cernunnos-XLF orthologs from sequence databases and sequence trace archives. Comparison of coding sequences revealed an excess of nonsynonymous substitutions consistent with positive selection on Cernunnos-XLF in the human lineage. The hotspots of adaptive evolution are concentrated around a specific structural domain, whose analogue in the structurally similar XRCC4 protein is involved in binding of another nonhomologous end-joining factor, DNA ligase IV. Conclusion Cernunnos-XLF is a microcephaly-associated locus newly identified to be under adaptive evolution in humans, and possibly played a role in human brain expansion. We speculate that Cernunnos-XLF may have contributed to the increased number of brain cells in humans by efficient double strand break repair, which helps to prevent frequent apoptosis of neuronal progenitors and aids mitotic cell cycle progression. Reviewers This article was reviewed by Chris Ponting and Richard Emes (nominated by Chris Ponting, Kateryna Makova, Gáspár Jékely and Eugene V. Koonin.

  18. Women and leadership positions in the Malian Ministry of agriculture ...

    African Journals Online (AJOL)

    This study is based on a comparative analysis of female and male employees in leadership positions in the Malian Ministry of Agriculture. Special emphasis is placed on the obstacles and challenges limiting women attaining leadership positions within the Ministry. It provides insights into gender and cultural bias within the ...

  19. A global limit load solution for plates with surface cracks under combined end force and cross-thickness bending

    International Nuclear Information System (INIS)

    Lei Yuebao; Fox, Mike J.H.

    2011-01-01

    A global limit load solution for rectangular surface cracks in plates under combined end force and cross-thickness bending is derived, which allows any combination of positive/negative end force and positive/negative cross-thickness moment. The solution is based on the net-section plastic collapse concept and, therefore, gives limit load values based on the Tresca yielding criterion. Solutions for both cases with and without crack face contact are derived when whole or part of the crack is located in the compressive stress zone. From the solution, particular global limit load solutions for plates with extended surface cracks and through-thickness cracks under the same loading conditions are obtained. The solution is consistent with the limit load solution for surface cracks in plates under combined tension and positive bending due to Goodall and Webster and Lei when both the applied end force and bending moment are positive. The solution reduces to the limit load solution for plain plates under combined end force and cross-thickness bending when the crack vanishes. - Highlights: → A global limit load solution for plates with surface cracks in plates is derived. → Combined positive/negative end force and positive/negative cross-thickness moment are considered. → The solution is based on the net-section plastic collapse concept.

  20. Generalized Grüneisen parameters and low temperature limit of ...

    Indian Academy of Sciences (India)

    The low temperature limit of volume thermal expansion calculated here for cad- mium and zirconium is found to be positive and so we expect a positive volume expansion down to 0 K even though the mode gammas are negative. The mea- surement of higher-order elastic constants and hence the calculation of the thermal.

  1. Pink-color sign in esophageal squamous neoplasia, and speculation regarding the underlying mechanism

    Science.gov (United States)

    Ishihara, Ryu; Kanzaki, Hiromitsu; Iishi, Hiroyasu; Nagai, Kengo; Matsui, Fumi; Yamashina, Takeshi; Matsuura, Noriko; Ito, Takashi; Fujii, Mototsugu; Yamamoto, Sachiko; Hanaoka, Noboru; Takeuchi, Yoji; Higashino, Koji; Uedo, Noriya; Tatsuta, Masaharu; Tomita, Yasuhiko; Ishiguro, Shingo

    2013-01-01

    AIM: To investigate the reasons for the occurrence of the pink-color sign of iodine-unstained lesions. METHODS: In chromoendoscopy, the pink-color sign of iodine-unstained lesions is recognized as useful for the diagnosis of esophageal squamous cell carcinoma. Patients with superficial esophageal neoplasms treated by endoscopic resection were included in the study. Areas of mucosa with and without the pink-color sign were evaluated histologically. The following histologic features that were possibly associated with the pink-color sign were evaluated. The keratinous layer and basal cell layer were classified as present or absent. Cellular atypia was classified as high grade, moderate grade or low grade, based on nuclear irregularity, mitotic figures, loss of polarity, chromatin pattern and nuclear/cytoplasmic ratio. Vascular change was assessed based on dilatation, tortuosity, caliber change and variability in shape. Vessels with these four findings were classified as positive for vascular change. Endoscopic images of the lesions were captured immediately after iodine staining, 2-3 min after iodine staining and after complete fading of iodine staining. Quantitative analysis of color changes after iodine staining was also performed. RESULTS: A total of 61 superficial esophageal neoplasms in 54 patients were included in the study. The lesions were located in the cervical esophagus in one case, the upper thoracic esophagus in 10 cases, the mid-thoracic esophagus in 33 cases, and the lower thoracic esophagus in 17 cases. The median diameter of the lesions was 20 mm (range: 2-74 mm). Of the 61 lesions, 28 were classified as pink-color sign positive and 33 as pink-color sign negative. The histologic diagnosis was high-grade intraepithelial neoplasia (HGIN) or cancer invading into the lamina propria in 26 of the 28 pink-color sign positive lesions. There was a significant association between pink-color sign positive epithelium and HGIN or invasive cancer (P = 0

  2. Damping at positive frequencies in the limit J⊥-->0 in the strongly correlated Hubbard model

    Science.gov (United States)

    Mohan, Minette M.

    1992-08-01

    I show damping in the two-dimensional strongly correlated Hubbard model within the retraceable-path approximation, using an expansion around dominant poles for the self-energy. The damping half-width ~J2/3z occurs only at positive frequencies ω>5/2Jz, the excitation energy of a pure ``string'' state of length one, where Jz is the Ising part of the superexchange interaction, and occurs even in the absence of spin-flip terms ~J⊥ in contrast to other theoretical treatments. The dispersion relation for both damped and undamped peaks near the upper band edge is found and is shown to have lost the simple J2/3z dependence characteristic of the peaks near the lower band edge. The position of the first three peaks near the upper band edge agrees well with numerical simulations on the t-J model. The weight of the undamped peaks near the upper band edge is ~J4/3z, contrasting with Jz for the weight near the lower band edge.

  3. Global positioning method based on polarized light compass system

    Science.gov (United States)

    Liu, Jun; Yang, Jiangtao; Wang, Yubo; Tang, Jun; Shen, Chong

    2018-05-01

    This paper presents a global positioning method based on a polarized light compass system. A main limitation of polarization positioning is the environment such as weak and locally destroyed polarization environments, and the solution to the positioning problem is given in this paper which is polarization image de-noising and segmentation. Therefore, the pulse coupled neural network is employed for enhancing positioning performance. The prominent advantages of the present positioning technique are as follows: (i) compared to the existing position method based on polarized light, better sun tracking accuracy can be achieved and (ii) the robustness and accuracy of positioning under weak and locally destroyed polarization environments, such as cloudy or building shielding, are improved significantly. Finally, some field experiments are given to demonstrate the effectiveness and applicability of the proposed global positioning technique. The experiments have shown that our proposed method outperforms the conventional polarization positioning method, the real time longitude and latitude with accuracy up to 0.0461° and 0.0911°, respectively.

  4. Integrated algorithms for RFID-based multi-sensor indoor/outdoor positioning solutions

    Science.gov (United States)

    Zhu, Mi.; Retscher, G.; Zhang, K.

    2011-12-01

    Position information is very important as people need it almost everywhere all the time. However, it is a challenging task to provide precise positions indoor/outdoor seamlessly. Outdoor positioning has been widely studied and accurate positions can usually be achieved by well developed GPS techniques but these techniques are difficult to be used indoors since GPS signal reception is limited. The alternative techniques that can be used for indoor positioning include, to name a few, Wireless Local Area Network (WLAN), bluetooth and Ultra Wideband (UWB) etc.. However, all of these have limitations. The main objectives of this paper are to investigate and develop algorithms for a low-cost and portable indoor personal positioning system using Radio Frequency Identification (RFID) and its integration with other positioning systems. An RFID system consists of three components, namely a control unit, an interrogator and a transponder that transmits data and communicates with the reader. An RFID tag can be incorporated into a product, animal or person for the purpose of identification and tracking using radio waves. In general, for RFID positioning in urban and indoor environments three different methods can be used, including cellular positioning, trilateration and location fingerprinting. In addition, the integration of RFID with other technologies is also discussed in this paper. A typical combination is to integrate RFID with relative positioning technologies such as MEMS INS to bridge the gaps between RFID tags for continuous positioning applications. Experiments are shown to demonstrate the improvements of integrating multiple sensors with RFID which can be employed successfully for personal positioning.

  5. Reduced H3K27me3 expression in Merkel cell polyoma virus-positive tumors.

    Science.gov (United States)

    Busam, Klaus J; Pulitzer, Melissa P; Coit, Daniel C; Arcila, Maria; Leng, Danielle; Jungbluth, Achim A; Wiesner, Thomas

    2017-06-01

    Merkel cell carcinoma is a primary cutaneous neuroendocrine carcinoma, which once metastatic is difficult to treat. Recent mutation analyses of Merkel cell carcinoma revealed a low number of mutations in Merkel cell polyomavirus-associated tumors, and a high number of mutations in virus-negative combined squamous cell and neuroendocrine carcinomas of chronically sun-damaged skin. We speculated that the paucity of mutations in virus-positive Merkel cell carcinoma may reflect a pathomechanism that depends on derangements of chromatin without alterations in the DNA sequence (epigenetic dysregulation). One central epigenetic regulator is the Polycomb repressive complex 2 (PRC2), which silences genomic regions by trimethylating (me3) lysine (K) 27 of histone H3, and thereby establishes the histone mark H3K27me3. Recent experimental research data demonstrated that PRC2 loss in mice skin results in the formation of Merkel cells. Prompted by these findings, we explored a possible contribution of PRC2 loss in human Merkel cell carcinoma. We examined the immunohistochemical expression of H3K27me3 in 35 Merkel cell carcinomas with pure histological features (22 primary and 13 metastatic lesions) and in 5 combined squamous and neuroendocrine carcinomas of the skin. We found a strong reduction of H3K27me3 staining in tumors with pure histologic features and virus-positive Merkel cell carcinomas. Combined neuroendocrine carcinomas had no or only minimal loss of H3K27me3 labeling. Our findings suggest that a PRC2-mediated epigenetic deregulation may play a role in the pathogenesis of virus-positive Merkel cell carcinomas and in tumors with pure histologic features.

  6. Positional Accuracy Assessment for Effective Shoreline Change ...

    African Journals Online (AJOL)

    Michael

    2016-06-01

    Jun 1, 2016 ... as backdrop in GIS environment. Positional error of ... integrated dataset obviously bore the cumulative effect of the input datasets. ... change. The shoreline, which is the interface between land ... modelling, which enables future shoreline change trend to ..... as gaps due to cloud cover and limitation of the.

  7. Experiments to test an intra-island scoop limiter on TEXT

    International Nuclear Information System (INIS)

    Evans, T.E.; DeGrassie, J.S.; Jackson, G.L.; Ohyabu, N.; Wootton, A.J.; Gentle, K.W.; Hodge, W.L.; McCool, S.C.; Phillips, P.E.; Rhodes, T.L.; Richards, B.; Ritz, C.P.; Rowan, W.L.

    1987-01-01

    An instrumented scoop limiter probe is being operated on TEXT to test the concept of limiter cooling and improved particle removal efficiencies using an externally-applied resonant magnetic field perturbation (the resonant helical divertor concept). Cooling of the limiter face has been demonstrated for limiter positions ranging from r L = 29.0 cm inward to r L = 25.5 cm (the TEXT primary poloidal hoop limiter radius r a = 27.0 cm). Pressure rises in the limiter throat of approximately 40% are observed under optimized conditions. Interchangable limiter heads with thicknesses of 1.0 cm and 0.3 cm have been used to examine particle ducting into the scoop aperture. Experimental results are discussed along with observations of the limiter floating potential, H α recycling emissions, pressure measurements, and edge density and temperature measurements. (orig.)

  8. Acknowledging and Appreciating the Full Spectrum of the Human Condition: School Psychology's (Limited) Focus on Positive Psychological Functioning

    Science.gov (United States)

    Froh, Jeffrey J.; Huebner, E. Scott; Youssef, Al-Jameela; Conte, Vincent

    2011-01-01

    This study is a content analysis of a random selection of 20% (N = 1,168) of articles from "School Psychology Quarterly", "Psychology in the Schools", the "Journal of School Psychology", and "School Psychology Review". Across the four journals, 27% of the articles had a positive focus, and the percentage of articles focused on the positive has…

  9. Comparative proteomics of leaves found at different stem positions of maize seedlings.

    Science.gov (United States)

    Chen, Yi-Bo; Wang, Dan; Ge, Xuan-Liang; Zhao, Biligen-Gaowa; Wang, Xu-Chu; Wang, Bai-Chen

    2016-07-01

    To better understand the roles of leaves at different stem positions during plant development, we measured the physiological properties of leaves 1-4 on maize seedling stems, and performed a proteomics study to investigate the differences in protein expression in the four leaves using two-dimensional difference gel electrophoresis and tandem mass spectrometry in conjunction with database searching. A total of 167 significantly differentially expressed protein spots were found and identified. Of these, 35% are involved in photosynthesis. By further analysis of the data, we speculated that in leaf 1 the seedling has started to transition from a heterotroph to an autotroph, development of leaf 2 is the time at which the seedling fully transitions from a heterotroph to an autotroph, and leaf maturity was reached only with fully expanded leaves 3 and 4, although there were still some protein expression differences in the two leaves. These results suggest that the different leaves make different contributions to maize seedling growth via modulation of the expression of the photosynthetic proteins. Together, these results provide insight into the roles of the different maize leaves as the plant develops from a heterotroph to an autotroph. Copyright © 2016 Elsevier GmbH. All rights reserved.

  10. Upper limits on the luminosity of the progenitor of type Ia supernova SN2014J

    DEFF Research Database (Denmark)

    Nielsen, M. T. B.; Gilfanov, M.; Bogdan, A.

    2014-01-01

    We analysed archival data of Chandra pre-explosion observations of the position of SN2014J in M82. No X-ray source at this position was detected in the data, and we calculated upper limits on the luminosities of the progenitor. These upper limits allow us to firmly rule out an unobscured supersof...

  11. A limited positioning system for memory.

    Science.gov (United States)

    Shapiro, Matthew

    2015-06-01

    The 2014 Nobel Prize for Physiology or Medicine is an enormous triumph for John O'Keefe and May-Britt and Edvard Moser and an historic event for cognitive and behavioral neuroscience. Neuronal representations decoded from action potentials form a mechanistic bridge between brain and mind and demonstrate the continuity of psychology with biology and physical science. The cognitive map theory powered an ongoing, international research program inspired by Hebb (The Organization of Behavior. New York, NY: Wiley) that showed the way toward linking specific patterns of neuronal activity to high level representation and processing. The prize celebrates a path that led from fundamental, philosophical questions about psychological space to enduring, scientific facts: place, head direction, grid, and boundary fields in the hippocampus, presubiculum, entorhinal cortex, and other brain circuits provide a cellular basis for spatial behavior, learning, and memory. By awarding this prize, the Nobel committee affirmed neuroethology and comparative psychology, marked the end of a chapter in one debate about the existence of animal cognition, and recognized cognitive neurophysiology. The "inner GPS" in the brain" demonstrates "a cellular basis for higher cognitive function." Animals represent, process, and use information defined by abstract relationships among items (O'Keefe and Conway,) to guide flexible, goal-directed actions. Beyond raising the ontological status of "animal mind," the committee agreed that abstract mental representations can be investigated rigorously by recording single unit activity in the brain of behaving animals. © 2015 Wiley Periodicals, Inc.

  12. Evolution of Indoor Positioning Technologies: A Survey

    Directory of Open Access Journals (Sweden)

    Ramon F. Brena

    2017-01-01

    Full Text Available Indoor positioning systems (IPS use sensors and communication technologies to locate objects in indoor environments. IPS are attracting scientific and enterprise interest because there is a big market opportunity for applying these technologies. There are many previous surveys on indoor positioning systems; however, most of them lack a solid classification scheme that would structurally map a wide field such as IPS, or omit several key technologies or have a limited perspective; finally, surveys rapidly become obsolete in an area as dynamic as IPS. The goal of this paper is to provide a technological perspective of indoor positioning systems, comprising a wide range of technologies and approaches. Further, we classify the existing approaches in a structure in order to guide the review and discussion of the different approaches. Finally, we present a comparison of indoor positioning approaches and present the evolution and trends that we foresee.

  13. Application of fault current limiters

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, A.

    2007-11-30

    This report presents the results of a study commissioned by the Department for Business, Enterprise and Industry (BERR; formerly the Department of Trade and Industry) into the application of fault current limiters in the UK. The study reviewed the current state of fault current limiter (FCL) technology and regulatory position in relation to all types of current limiters. It identified significant research and development work with respect to medium voltage FCLs and a move to high voltage. Appropriate FCL technologies being developed include: solid state breakers; superconducting FCLs (including superconducting transformers); magnetic FCLs; and active network controllers. Commercialisation of these products depends on successful field tests and experience, plus material development in the case of high temperature superconducting FCL technologies. The report describes FCL techniques, the current state of FCL technologies, practical applications and future outlook for FCL technologies, distribution fault level analysis and an outline methodology for assessing the materiality of the fault level problem. A roadmap is presented that provides an 'action agenda' to advance the fault level issues associated with low carbon networks.

  14. Positional Velar Fronting: An Updated Articulatory Account

    Science.gov (United States)

    Byun, Tara McAllister

    2012-01-01

    This study develops the hypothesis that the child-specific phenomenon of positional velar fronting can be modeled as the product of phonologically encoded articulatory limitations unique to immature speakers. Children have difficulty executing discrete tongue movements, preferring to move the tongue and jaw as a single unit. This predisposes the…

  15. Accounting for False Positive HIV Tests: Is Visceral Leishmaniasis Responsible?

    Science.gov (United States)

    Shanks, Leslie; Ritmeijer, Koert; Piriou, Erwan; Siddiqui, M Ruby; Kliescikova, Jarmila; Pearce, Neil; Ariti, Cono; Muluneh, Libsework; Masiga, Johnson; Abebe, Almaz

    2015-01-01

    Co-infection with HIV and visceral leishmaniasis is an important consideration in treatment of either disease in endemic areas. Diagnosis of HIV in resource-limited settings relies on rapid diagnostic tests used together in an algorithm. A limitation of the HIV diagnostic algorithm is that it is vulnerable to falsely positive reactions due to cross reactivity. It has been postulated that visceral leishmaniasis (VL) infection can increase this risk of false positive HIV results. This cross sectional study compared the risk of false positive HIV results in VL patients with non-VL individuals. Participants were recruited from 2 sites in Ethiopia. The Ethiopian algorithm of a tiebreaker using 3 rapid diagnostic tests (RDTs) was used to test for HIV. The gold standard test was the Western Blot, with indeterminate results resolved by PCR testing. Every RDT screen positive individual was included for testing with the gold standard along with 10% of all negatives. The final analysis included 89 VL and 405 non-VL patients. HIV prevalence was found to be 12.8% (47/ 367) in the VL group compared to 7.9% (200/2526) in the non-VL group. The RDT algorithm in the VL group yielded 47 positives, 4 false positives, and 38 negatives. The same algorithm for those without VL had 200 positives, 14 false positives, and 191 negatives. Specificity and positive predictive value for the group with VL was less than the non-VL group; however, the difference was not found to be significant (p = 0.52 and p = 0.76, respectively). The test algorithm yielded a high number of HIV false positive results. However, we were unable to demonstrate a significant difference between groups with and without VL disease. This suggests that the presence of endemic visceral leishmaniasis alone cannot account for the high number of false positive HIV results in our study.

  16. Accounting for False Positive HIV Tests: Is Visceral Leishmaniasis Responsible?

    Directory of Open Access Journals (Sweden)

    Leslie Shanks

    Full Text Available Co-infection with HIV and visceral leishmaniasis is an important consideration in treatment of either disease in endemic areas. Diagnosis of HIV in resource-limited settings relies on rapid diagnostic tests used together in an algorithm. A limitation of the HIV diagnostic algorithm is that it is vulnerable to falsely positive reactions due to cross reactivity. It has been postulated that visceral leishmaniasis (VL infection can increase this risk of false positive HIV results. This cross sectional study compared the risk of false positive HIV results in VL patients with non-VL individuals.Participants were recruited from 2 sites in Ethiopia. The Ethiopian algorithm of a tiebreaker using 3 rapid diagnostic tests (RDTs was used to test for HIV. The gold standard test was the Western Blot, with indeterminate results resolved by PCR testing. Every RDT screen positive individual was included for testing with the gold standard along with 10% of all negatives. The final analysis included 89 VL and 405 non-VL patients. HIV prevalence was found to be 12.8% (47/ 367 in the VL group compared to 7.9% (200/2526 in the non-VL group. The RDT algorithm in the VL group yielded 47 positives, 4 false positives, and 38 negatives. The same algorithm for those without VL had 200 positives, 14 false positives, and 191 negatives. Specificity and positive predictive value for the group with VL was less than the non-VL group; however, the difference was not found to be significant (p = 0.52 and p = 0.76, respectively.The test algorithm yielded a high number of HIV false positive results. However, we were unable to demonstrate a significant difference between groups with and without VL disease. This suggests that the presence of endemic visceral leishmaniasis alone cannot account for the high number of false positive HIV results in our study.

  17. Computerized working memory training has positive long-term effect in very low birthweight preschool children.

    Science.gov (United States)

    Grunewaldt, Kristine Hermansen; Skranes, Jon; Brubakk, Ann-Mari; Lähaugen, Gro C C

    2016-02-01

    Working memory deficits are frequently found in children born preterm and have been linked to learning disabilities, and cognitive and behavioural problems. Our aim was to evaluate if a computerized working memory training program has long-term positive effects on memory, learning, and behaviour in very-low-birthweight (VLBW) children at age 5 to 6 years. This prospective, intervention study included 20 VLBW preschool children in the intervention group and 17 age-matched, non-training VLBW children in the comparison group. The intervention group trained with the Cogmed JM working memory training program daily for 5 weeks (25 training sessions). Extensive neuropsychological assessment and parental questionnaires were performed 4 weeks after intervention and at follow-up 7 months later. For most of the statistical analyses, general linear models were applied. At follow-up, higher scores and increased or equal performance gain were found in the intervention group than the comparison group on memory for faces (p=0.012), narrative memory (p=0.002), and spatial span (p=0.003). No group differences in performance gain were found for attention and behaviour. Computerized working memory training seems to have positive and persisting effects on working memory, and visual and verbal learning, at 7-month follow-up in VLBW preschool children. We speculate that such training is beneficial by improving the ability to learn from the teaching at school and for further cognitive development. © 2015 Mac Keith Press.

  18. Positioning Sex Educators: A Critical Ethnography of a Professional Development Workshop

    Science.gov (United States)

    Scott, Brigitte C.

    2013-01-01

    In this ethnographic research, I offer an analysis of a state-sponsored professional development workshop for sex educators. Positioning theory is used to understand how the lived space of the workshop -- including texts, talk and silence -- positions sex education teachers as professionals and practitioners with certain (limited) speaking rights…

  19. The mystery of flavor

    International Nuclear Information System (INIS)

    Peccei, R. D.

    1998-01-01

    After outlining some of the issues surrounding the flavor problem, I present three speculative ideas on the origin of families. In turn, families are conjectured to arise from an underlying preon dynamics; from random dynamics at very short distances; or as a result of compactification in higher dimensional theories. Examples and limitations of each of these speculative scenarios are discussed

  20. Experiments to test an intra-island scoop limiter on TEXT

    International Nuclear Information System (INIS)

    Evans, T.E.; deGrassie, J.S.; Jackson, G.L.; Ohyabu, N.; Karger, F.; Haas, G.

    1986-07-01

    An instrumented scoop limiter probe is being operated on TEXT to test the concept of limiter cooling and improved particle removal efficiencies using an externally-applied resonant magnetic field perturbation (the resonant helical divertor concept). Cooling of the limiter face has been demonstrated for limiter positions ranging from γ/sub L/ = 29.0 cm inward to γ/sub L/ = 25.5 cm (the TEXT primary poloidal hoop limiter radius γ/sub a/ = 27.0 cm). Pressure rises in the limiter throat of approximately 40% are observed under optimized conditions. Interchangeable limiter heads with thicknesses of 1.0 cm and 0.3 cm have been used to examine particle ducting into the scoop aperture. Experimental results are discussed along with observations of the limiter floating potential, H/sub α/ recycling emissions, pressure measurements, and edge density and temperature measurements

  1. Incentive-Rewarding Mechanism for User-position Control in Mobile Services

    Science.gov (United States)

    Yoshino, Makoto; Sato, Kenichiro; Shinkuma, Ryoichi; Takahashi, Tatsuro

    When the number of users in a service area increases in mobile multimedia services, no individual user can obtain satisfactory radio resources such as bandwidth and signal power because the resources are limited and shared. A solution for such a problem is user-position control. In the user-position control, the operator informs users of better communication areas (or spots) and navigates them to these positions. However, because of subjective costs caused by subjects moving from their original to a new position, they do not always attempt to move. To motivate users to contribute their resources in network services that require resource contributions for users, incentive-rewarding mechanisms have been proposed. However, there are no mechanisms that distribute rewards appropriately according to various subjective factors involving users. Furthermore, since the conventional mechanisms limit how rewards are paid, they are applicable only for the network service they targeted. In this paper, we propose a novel incentive-rewarding mechanism to solve these problems, using an external evaluator and interactive learning agents. We also investigated ways of appropriately controlling rewards based on user contributions and system service quality. We applied the proposed mechanism and reward control to the user-position control, and demonstrated its validity.

  2. Beam position monitor system for storage rings

    International Nuclear Information System (INIS)

    Nakamura, M.; Hinkson, J.A.

    1985-05-01

    Beam position monitors (BPM) for synchrotron light storage rings usually consist of beam pickup electrodes, coaxial relays and a narrowband receiver. While accurate, these systems are slow and of limited use in the commissioning of an accelerator. A beam position monitor is described which is intended to be a principal diagnostic during debug and routine running of a storage ring. It is capable of measuring the position of a single bunch on the first or nth orbit to an accuracy of a few percent. Stored beam position is more accurately measured with averaging techniques. Beam position changes can be studied in a bandwidth from DC to a few MHz. The beam monitor electronics consist of a separate amplification, detection, and sampling channel for each beam pickup electrode. Fast switches in each channel permit selection of the nth turn for measurement (single bunch mode). A calibration pulse is injected into each channel after beam measurement to permit gain offsets to be measured and removed from the final data. While initially more costly than the usual beam position monitor system, this sytem will pay for itself in reduced storage ring debug and trouble shooting time. 5 refs., 5 figs

  3. Beam position monitors for the high brightness lattice

    International Nuclear Information System (INIS)

    Ring, T.

    1985-06-01

    Engineering developments associated with the high brightness lattice and the projected change in machine operating parameters will inherently affect the diagnostics systems and devices installed at present in the storage ring. This is particularly true of the beam position monitoring (BPI) system. The new sixteen unit cell lattice with its higher betatron tune values and the limited space available in the redesigned machine straights for fitting standard BPI vessels forces a fundamental re-evaluation of the beam position monitor system. The design aims for the new system are based on accepting the space limitations imposed while still providing the monitor points required to give good radial and vertical closed orbit plots. The locations of BPI's in the redesigned machine straights is illustrated. A description of the new BPI assemblies and their calibration is given. The BPI's use capacitance button type pick-ups; their response is described. (U.K.)

  4. Heterogeneous Expectations and Speculative Behavior in Insurance-Linked Securities

    Directory of Open Access Journals (Sweden)

    Min Zheng

    2015-01-01

    Full Text Available Within the framework of heterogeneous agent models, this paper analyzes the impact factors on the issuance of an insurance-linked security (ILS, and gives an ILS pricing formula and the conditions of existence and stability of the issue price. We consider two cases: fixed supply and flexible supply. We find that, in the fixed volume case, to assure the successful issuance of an ILS, an appropriate volume of the ILS is necessary, and to attract investors, the ILS should pay a positive premium which can help investors to enhance the efficient frontier of their portfolio. In the flexible supply case, we show that the issue price of an ILS is given by the weighted average of different beliefs about the discounted ILS return, and the stability of the issue price depends on the numbers of investors and sponsors and the extrapolation rate to the ILS of investors. In addition, whether an ILS has the hedging ability to sponsors depends on their own understanding about the ILS coupon and the relationship between the recovery from the ILS and their liability, but how much the risk of sponsors can be hedged relies on the ILS coupon expected by investors.

  5. Quantum interference of position and momentum: A particle propagation paradox

    Science.gov (United States)

    Hofmann, Holger F.

    2017-08-01

    Optimal simultaneous control of position and momentum can be achieved by maximizing the probabilities of finding their experimentally observed values within two well-defined intervals. The assumption that particles move along straight lines in free space can then be tested by deriving a lower limit for the probability of finding the particle in a corresponding spatial interval at any intermediate time t . Here, it is shown that this lower limit can be violated by quantum superpositions of states confined within the respective position and momentum intervals. These violations of the particle propagation inequality show that quantum mechanics changes the laws of motion at a fundamental level, providing a different perspective on causality relations and time evolution in quantum mechanics.

  6. Assessment of HIV-positive in-patients using the International ...

    African Journals Online (AJOL)

    version checklist was used to assess the impairments, activity limitations and participation restrictions experienced by a sample of HIV-positive in-patients admitted to Chris Hani Baragwanath Hospital in Johannesburg, South Africa. Laboratory ...

  7. Perception of Women in Top Managerial Positions in Poland

    Directory of Open Access Journals (Sweden)

    Anna Górska

    2017-03-01

    Full Text Available Purpose: The aim of the pilot study was to fnd out whether the perception of candidates for leadership positions differs along with the gender of the candidate in Poland. Methodology: In order to answer the question, the author has conducted a preliminary experiment on 50 MBA students, which were experienced in recruitment. Two identical CVs were randomly distributed among the participants, with either a male or female version of the CV. Basing on the provided information, respondents were to decide on among others hireability, likeability and offered income to the given candidate. Findings: The experiment revealed that the female candidate for the CEO position was perceived and evaluated differently than the male candidate. Thus, the experiment indicated that gender inequality may already appear at the phase of recruitment for higher positions. Originality: The presented study analyzed perceptions of experienced recruiters, which may suggest that such behaviors and patters may be repeated in a non-laboratory environment. Limitations: A limitation of the pilot study is the low number of participants and therefore further research should be conducted.

  8. 14 CFR 25.523 - Design weights and center of gravity positions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Design weights and center of gravity... Design weights and center of gravity positions. (a) Design weights. The water load requirements must be...) must be used. (b) Center of gravity positions. The critical centers of gravity within the limits for...

  9. Limit regulation system for pressurized water nuclear reactors

    International Nuclear Information System (INIS)

    Aleite, W.; Bock, H.W.

    1976-01-01

    Described is a limit regulation system for a pressurized water nuclear reactor in combination with a steam generating system connected to a turbine, the nuclear reactor having control rods as well as an operational regulation system and a protective system, which includes reactor power limiting means operatively associated with the control rods for positioning the same and having response values between operating ranges of the operational regulation system, on the one hand, and response values of the protective system, on the other hand, and a live steam-minimal pressure regulation system cooperating with the reactor power limiting means and operatively connected to a steam inlet valve to the turbine for controlling the same

  10. Occupational Exposures and Chronic Airflow Limitation

    Directory of Open Access Journals (Sweden)

    Helen Dimich-Ward

    1996-01-01

    Full Text Available The recent literature was reviewed to evaluate whether chronic airflow limitation is associated with occupational exposures to dusts. Only those studies that controlled for the effects of smoking were included. There is compelling evidence that exposure to inorganic dusts, such as from coal and hardrock mining or asbestos, are associated with the development of chronic airflow limitation, independently of pneumoconiosis. Nonsmoking gold miners are particularly at high risk of airflow obstruction and emphysema. Findings from studies of organic dusts, such as exposures to wood, cotton, grain or other agricultural dusts, or to mixed dust exposures, were less consistent but tended to show positive dose-response associations. In the majority of studies, no statistical interaction was shown between dust exposures and smoking; however, the effects of the dust exposures were often more pronounced. An occupational history should be considered, in addition to a smoking history, as an integral part of an investigation of chronic airflow limitation in a patient.

  11. Positive muscle phenomena-diagnosis, pathogenesis and associated disorders

    NARCIS (Netherlands)

    Kortman, Hans G.; Veldink, Jan H.; Drost, Gea

    Positive muscle phenomena arise owing to various forms of spontaneous muscle hyperactivity originating in motor neurons or in the muscle itself. Although they are common in a wide range of neurological and non-neurological diseases, clinical and scientific data on these phenomena are limited, and

  12. Effects of line dancing on physical function and perceived limitation in older adults with self-reported mobility limitations.

    Science.gov (United States)

    Bennett, Crystal G; Hackney, Madeleine E

    2018-06-01

    Older adults with mobility limitations are at greater risk for aging-related declines in physical function. Line dancing is a popular form of exercise that can be modified, and is thus feasible for older adults with mobility limitations. The purpose of this study was to assess the effects of 8 weeks of line dancing on balance, muscle strength, lower extremity function, endurance, gait speed, and perceived mobility limitations. An experimental design randomly assigned older adults to either an 8-week line dancing or usual care group. The convenience sample consisted of 23 participants with mobility limitations (age range: 65-93 years). The intervention used simple routines from novice line dance classes. At baseline and at 8 weeks, balance, knee muscle strength, lower extremity function, endurance, gait speed, and mobility limitations were measured. ANCOVA tests were conducted on each dependent variable to assess the effects of the intervention over time. Results found significant positive differences for the intervention group in lower extremity function (p dancing significantly improved physical function and reduced self-reported mobility limitations in these individuals. Line dancing could be recommended by clinicians as a potential adjunct therapy that addresses mobility limitations. Implications for Rehabilitation Line dancing may be an alternative exercise for older adults who need modifications due to mobility limitations. Line dancing incorporates cognitive and motor control. Line dancing can be performed alone or in a group setting. Dancing improves balance which can reduce risk of falls.

  13. Limitation of Piston Centre Shift in Free Piston Stirling Engines

    Energy Technology Data Exchange (ETDEWEB)

    Van der Woude, R.R. [ECN Energy in the Built Environment and Networks, Petten (Netherlands)

    2006-09-15

    Piston centre shift is one of the phenomena setting Free Piston engines apart from traditional kinematic engines. In kinematic engines the piston centre position is determined by the design of the engine's internal mechanisms. In Free Piston engines however, the piston's mid-stroke position is determined by the balance of forces acting on the piston, in particular flexure and gas pressure forces. As a result, a mean pressure difference across the piston emerging during engine operation will cause the piston mid-stroke position to shift away from the geometrical centre. This process will continue until a new balance is reached with the flexure forces counteracting the new mean pressure balance. Yet, before the new equilibrium is reached, the resulting piston centre shift may have grown to such an extent that piston overstrokes have become inevitable. In order to limit piston centre shift and prevent piston overstrokes, several solutions have been proposed in the past. Popular solutions include ingenious mechanisms to vent gas between the spaces separated by the piston, in an attempt to limit the pressure difference. Enatec however has adopted a different approach by applying a precisely determined clearance between the piston and cylinder. With the right shape the clearance effectively limits the mean pressure difference across the piston and therefore limits the extent of the piston centre drift. Taking benefit of tightly controlled tolerances of both piston and cylinder, Enatec has demonstrated the effectiveness of this simple concept in series produced engines.

  14. Does Andrews facial analysis predict esthetic sagittal maxillary position?

    Science.gov (United States)

    Resnick, Cory M; Daniels, Kimberly M; Vlahos, Maryann

    2018-04-01

    Cephalometric analyses have limited utility in planning maxillary sagittal position for orthognathic surgery. In Six Elements of Orofacial Harmony, Andrews quantified maxillary position relative to forehead projection and angulation and proposed an ideal relationship. The purpose of this study was to investigate the ability of this technique to predict esthetic sagittal maxillary position. Survey study including a male and female with straight facial profiles, normal maxillary incisor angulations, and Angle's Class I. Maxillary position was modified on lateral photographs to create 5 images for each participant with incisor-goal anterior limit line (GALL) distances of -4, -2, 0, +2, and +4 mm. A series of health care professionals and laypeople were asked to rate each photo in order of attractiveness. A total of 100 complete responses were received. Incisor-GALL distances of +4 mm (41%) and +2 mm (40%) were most commonly considered "most esthetic" for the female volunteer (P < .001). For the male volunteer, there were 2 peak "most esthetic" responses: incisor-GALL distances of 0 mm (37%) and -4 mm (32%) (P < .001). Respondents considered maxillary incisor position 2 to 4 mm anterior to GALL most attractive in a woman and 0 to 4 mm posterior to GALL most esthetic in a man. Using these modified target distances, this analysis may be useful for orthognathic surgery planning. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Recall of symptoms and treatment of syphilis and yaws by healthy blood donors screening positive for syphilis in Kumasi, Ghana.

    Science.gov (United States)

    Sarkodie, Francis; Owusu-Dabo, Ellis; Hassall, Oliver; Bates, Imelda; Bygbjerg, Ib C; Ullum, Henrik

    2016-09-01

    To describe the recalled medical history, clinical manifestations, and treatment of yaws and syphilis by syphilis seroreactive blood donors in Kumasi, Ghana. Of the blood donors at Komfo Anokye Teaching Hospital, Kumasi, Ghana tested with the syphilis rapid diagnostic test (RDT) and later by rapid plasma reagin (RPR) test, 526 were seroreactive. Four hundred and seventy-one (89.5%) of these subjects were confirmed with the Ortho-Vitros Syphilis TP test as the gold standard and were interviewed to determine past or present clinical manifestations of yaws and syphilis. Of the 471 respondent donors, 28 (5.9%) gave a history of skin lesions and sores; four (14.3%) of these subjects, who were all male and RPR-positive, recalled a diagnosis of syphilis. All four reported having had skin lesions/bumps with slow-healing sores, but only one of them had had these symptoms before the age of 15 years. A small proportion of confirmed seroreactive donors in this sample had any recall of symptoms or treatment for yaws or syphilis. These data suggest that clinical questioning adds little further information to the current screening algorithm. The relative contribution of yaws and syphilis to frequent positive tests in endemic areas remains speculative. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  16. Do limiting factors at Alaskan treelines shift with climatic regimes?

    International Nuclear Information System (INIS)

    Ohse, B; Jansen, F; Wilmking, M

    2012-01-01

    Trees at Alaskan treelines are assumed to be limited by temperature and to expand upslope and/or to higher latitudes with global warming. However, recent studies describe negative temperature responses and drought stress of Alaskan treeline trees in recent decades. In this study, we have analyzed the responses of treeline white spruce to temperature and precipitation according to different climatic regimes in Alaska, described as negative (cool) and positive (warm) phases of the Pacific Decadal Oscillation (PDO). We found that in three consecutive phases (positive from 1925–46, negative from 1947–76, and positive again from 1977–98), the growth responses to temperature and precipitation differed markedly. Before 1947, in a phase of warm winters and with summer temperatures being close to the century mean, the trees at most sites responded positively to summer temperature, as one would expect from treeline trees at northern high latitudes. Between 1947 and 1976, a phase of cold winters and average summers, the trees showed similar responses, but a new pattern of negative responses to the summer temperature of the year prior to growth coupled with positive responses to the precipitation in the same year emerged at some sites. As the precipitation was relatively low at those sites, we assume that drought stress might have played a role. However, the climate responses were not uniform but were modified by regional gradients (trees at northern sites responded more often to temperature than trees at southern sites) and local site conditions (forest trees responded more often to precipitation than treeline trees), possibly reflecting differences in energy and water balance across regions and sites, respectively. However, since the shift in the PDO in 1976 from a negative to a positive phase, the trees’ climate–growth responses are much less pronounced and climate seems to have lost its importance as a limiting factor for the growth of treeline white spruce. If

  17. Socioeconomic position and participation in colorectal cancer screening

    DEFF Research Database (Denmark)

    Frederiksen, B L; Jørgensen, Torben; Brasso, K

    2010-01-01

    Colorectal cancer (CRC) screening with faecal occult blood test (FOBT) has the potential to reduce the incidence and mortality of CRC. Screening uptake is known to be inferior in people with low socioeconomic position (SEP) when compared with those with high position; however, the results of most...... information on education, employment, and income to encompass different but related aspects of socioeconomic stratification. Also, the impact of ethnicity and cohabiting status was analysed.......Colorectal cancer (CRC) screening with faecal occult blood test (FOBT) has the potential to reduce the incidence and mortality of CRC. Screening uptake is known to be inferior in people with low socioeconomic position (SEP) when compared with those with high position; however, the results of most...... previous studies have limited value because they are based on recall or area-based measures of socioeconomic position, and might thus be subject to selective participation and misclassification. In this study we investigated differences in CRC screening participation using register-based individual...

  18. Psychiatry, religion, positive emotions and spirituality.

    Science.gov (United States)

    Vaillant, George E

    2013-12-01

    This paper proposes that eight positive emotions: awe, love/attachment, trust/faith, compassion, gratitude, forgiveness, joy and hope constitute what we mean by spirituality. These emotions have been grossly ignored by psychiatry. The two sciences that I shall employ to demonstrate this definition of spirituality will be ethology and neuroscience. They are both very new. I will argue that spirituality is not about ideas, sacred texts and theology. Rather, spirituality is all about emotion and social connection that are more dependent on the limbic system than the cortex. Specific religions, for all their limitations, are often the portal through which positive emotions are brought into conscious attention. Neither Freud nor psychiatric textbooks ever mention emotions like joy and gratitude. Hymns and psalms give these emotions pride of place. Our whole concept of psychotherapy might change, if clinicians set about enhancing positive emotions, rather than focusing only on the negative ones. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Tanzania Telecommunication Company Limited as a Mobile Service Provider

    OpenAIRE

    Ndyamukama, Edna

    2014-01-01

    This bachelor’s thesis was researched and written under the consent and authority of Tanzania Telecommunication Company Limited (TTCL), with the purpose to find out ways of improving sales and profits of its mobile service department. The mobile service department of TTCL is performing poorly as compared to its competitors despite being managed by a strategically positioned and experienced company in tele-communication services. It was also meant to find out the positive contribution of compe...

  20. Investigation of limiter recycling in the divertor tokamak ASDEX

    International Nuclear Information System (INIS)

    Wagner, F.

    1981-08-01

    A divertor experiment like the ASDEX tokamak is especially suited for studying ion recycling at a material limiter, because the plasma can alternatively be limited by a magnetic limiter (separatrix) or by a material limiter. The role of the material limiter in ion recycling is documented by observing the increase in charge exchange flux emitted at the limiter position, and the decrease in external gas input necessary to keep the plasma line density invariant, when the material limiter is moved to the plasma. Ion recycling occurs predominantly at the outside section of a ring limiter. The limiter material saturates shortly after the start of the discharge. About 60% of the total recycling occurs at the limiter, which is nearly 100% of the ion recycling. The remaining 40% of the total recycling is carried by charge exchange neutrals. Due to saturation, the recycling coefficient at the limiter is 1; the recycling coefficient of the charge exchange neutrals at the wall is approximately 0.5 giving rise to a total recycling coefficient of limiter discharges of 0.8-0.9. It is observed that the plasma resistivity increases when the material limiter is moved toward the separatrix. The increase in Zsub(eff) can tentatively be explained by proton sputtering. (orig.)

  1. Position detectors, methods of detecting position, and methods of providing positional detectors

    Science.gov (United States)

    Weinberg, David M.; Harding, L. Dean; Larsen, Eric D.

    2002-01-01

    Position detectors, welding system position detectors, methods of detecting various positions, and methods of providing position detectors are described. In one embodiment, a welding system positional detector includes a base that is configured to engage and be moved along a curved surface of a welding work piece. At least one position detection apparatus is provided and is connected with the base and configured to measure angular position of the detector relative to a reference vector. In another embodiment, a welding system positional detector includes a weld head and at least one inclinometer mounted on the weld head. The one inclinometer is configured to develop positional data relative to a reference vector and the position of the weld head on a non-planar weldable work piece.

  2. Herbivory and pollen limitation at the upper elevational range limit of two forest understory plants of eastern North America.

    Science.gov (United States)

    Rivest, Sébastien; Vellend, Mark

    2018-01-01

    Studies of species' range limits focus most often on abiotic factors, although the strength of biotic interactions might also vary along environmental gradients and have strong demographic effects. For example, pollinator abundance might decrease at range limits due to harsh environmental conditions, and reduced plant density can reduce attractiveness to pollinators and increase or decrease herbivory. We tested for variation in the strength of pollen limitation and herbivory by ungulates along a gradient leading to the upper elevational range limits of Trillium erectum (Melanthiaceae) and Erythronium americanum (Liliaceae) in Mont Mégantic National Park, Québec, Canada. In T. erectum, pollen limitation was higher at the range limit, but seed set decreased only slightly with elevation and only in one of two years. In contrast, herbivory of T. erectum increased from 60% at the upper elevational range limit. In E. americanum , we found no evidence of pollen limitation despite a significant decrease in seed set with elevation, and herbivory was low across the entire gradient. Overall, our results demonstrate the potential for relatively strong negative interactions (herbivory) and weak positive interactions (pollination) at plant range edges, although this was clearly species specific. To the extent that these interactions have important demographic consequences-highly likely for herbivory on Trillium , based on previous studies-such interactions might play a role in determining plant species' range limits along putatively climatic gradients.

  3. Geometric derivation of the quantum speed limit

    International Nuclear Information System (INIS)

    Jones, Philip J.; Kok, Pieter

    2010-01-01

    The Mandelstam-Tamm and Margolus-Levitin inequalities play an important role in the study of quantum-mechanical processes in nature since they provide general limits on the speed of dynamical evolution. However, to date there has been only one derivation of the Margolus-Levitin inequality. In this paper, alternative geometric derivations for both inequalities are obtained from the statistical distance between quantum states. The inequalities are shown to hold for unitary evolution of pure and mixed states, and a counterexample to the inequalities is given for evolution described by completely positive trace-preserving maps. The counterexample shows that there is no quantum speed limit for nonunitary evolution.

  4. Productive diversification in natural resource abundant countries : limitations, policies and the experience of Argentina in the 2000s

    NARCIS (Netherlands)

    L.A. Serino (Leandro)

    2009-01-01

    textabstractThe debate on the pattern of specialization in natural resource abundant countries has re-emerged as demand for raw materials and food products from the rapidly growing East Asian countries, speculation in financial markets, and changes in production techniques augmented the

  5. 7 CFR 1400.204 - Limited partnerships, limited liability partnerships, limited liability companies, corporations...

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Limited partnerships, limited liability partnerships..., limited liability partnerships, limited liability companies, corporations, and other similar legal entities. (a) A limited partnership, limited liability partnership, limited liability company, corporation...

  6. The mystery of flavor

    International Nuclear Information System (INIS)

    Peccei, R.D.

    1998-01-01

    After outlining some of the issues surrounding the flavor problem, I present three speculative ideas on the origin of families. In turn, families are conjectured to arise from an underlying preon dynamics; from random dynamics at very short distances; or as a result of compactification in higher dimensional theories. Examples and limitations of each of these speculative scenarios are discussed. copyright 1998 American Institute of Physics

  7. Ion extraction from positively biased laser-ablation plasma

    International Nuclear Information System (INIS)

    Isono, Fumika; Nakajima, Mitsuo; Hasegawa, Jun; Horioka, Kazuhiko

    2016-01-01

    Ions were extracted through a grounded grid from a positively biased laser-ablation plasma and the behaviors were investigated. Since the plasma was positively biased against the grounded wall, we could extract the ions without insulated gap. We confirmed formation of a virtual anode when we increased the distance between the grid and the ion collector. Results also indicated that when the ion flux from the ablation plasma exceeded a critical value, the current was strongly suppressed to the space charge limited level due to the formation of virtual anode.

  8. Subwavelength position measurements with running-wave driving fields

    Energy Technology Data Exchange (ETDEWEB)

    Evers, Joerg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Qamar, Sajid [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Centre for Quantum Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan)

    2011-08-15

    Subwavelength position measurement of quantum particles is discussed. Our setup is based on a closed-loop driving-field configuration, which enforces a sensitivity of the particle dynamics to the phases of the applied fields. Thus, running wave fields are sufficient, avoiding limitations associated with standing-wave-based localization schemes. Reversing the directions of the driving laser fields switches between different magnification levels for the position determination. This allows us to optimize the localization, and at the same time eliminates the need for additional classical measurements common to all previous localization schemes based on spatial periodicity.

  9. Lymphocyte subsets are influenced by positivity levels in healthy subjects before and after mild acute stress.

    Science.gov (United States)

    Caprara, Gian Vittorio; Nisini, Roberto; Castellani, Valeria; Vittorio, Pasquali; Alessandri, Guido; Vincenzo, Ziparo; Claudia, Ferlito; Valentina, Germano; Andrea, Picchianti Diamanti; Biondo, Michela Ileen; Milanetti, Francesca; Salerno, Gerardo; Vincenzo, Visco; Mario, Pietrosanti; Aniballi, Eros; Simonetta, Salemi; Angela, Santoni; D'Amelio, Raffaele

    2017-08-01

    In the current study, the possible association of positivity (POS), recently defined as general disposition to view life under positive outlook, with immune markers and post-stress modifications, was analyzed. Circulating lymphocyte subsets and serum cytokine levels were evaluated before and after a standard mild acute stress test, in 41 healthy students, previously selected by a questionnaire for their level of POS (high [POS-H] and low [POS-L]). The CD3 + and CD4 + cell frequency was higher in the POS-H students before and after acute stress. CD4 + subpopulation analysis revealed baseline higher terminally differentiated frequency in the POS-H, whereas higher effector memory frequency was present in the POS-L students. Moreover, the frequency of post-stress B cells was higher in the POS-H students. The mild-stress test was associated to an increase of the IL-10 mean values, while mean values of the other cytokines tested did not change significantly. It is tempting to speculate that IL-10 may work as biomarker of response to acute mild stress and that POS-H may be associated to a better capacity of the immune system to contrast the disturbing effects of mild acute stress. Yet further studies on lymphocyte subset absolute number and function of larger and different populations are needed to definitively prove these preliminary observations. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  10. Beyond Speculative Robot Ethics

    NARCIS (Netherlands)

    Smits, M.; Van der Plas, A.

    2010-01-01

    In this article we develop a dialogue model for robot technology experts and designated users to discuss visions on the future of robotics in long-term care. Our vision assessment study aims for more distinguished and more informed visions on future robots. Surprisingly, our experiment also lead to

  11. In-vitro evaluation of limitations and possibilities for the future use of intracorporeal gas exchangers placed in the upper lobe position.

    Science.gov (United States)

    Schumer, Erin; Höffler, Klaus; Kuehn, Christian; Slaughter, Mark; Haverich, Axel; Wiegmann, Bettina

    2018-03-01

    The lack of donor organs has led to the development of alternative "destination therapies", such as a bio-artificial lung (BA) for end-stage lung disease. Ultimately aiming at a fully implantable BA, general capabilities and limitations of different oxygenators were tested based on the model of BA positioning at the right upper lobe. Three different-sized oxygenators (neonatal, paediatric, and adult) were tested in a mock circulation loop regarding oxygenation and decarboxylation capacities for three respiratory pathologies. Blood flows were imitated by a roller pump, and respiration was imitated by a mechanical ventilator with different FiO 2 applications. Pressure drops across the oxygenators and the integrity of the gas-exchange hollow fibers were analyzed. The neonatal oxygenator proved to be insufficient regarding oxygenation and decarboxylation. Despite elevated pCO 2 levels, the paediatric and adult oxygenators delivered comparable sufficient oxygen levels, but sufficient decarboxylation across the oxygenators was ensured only at flow rates of 0.5 L min. Only the adult oxygenator indicated no significant pressure drops. For all tested conditions, gas-exchange hollow fibers remained intact. This is the first study showing the general feasibility of delivering sufficient levels of gas exchange to an intracorporeal BA via patient's breathing, without damaging gas-exchange hollow fiber membranes.

  12. Indoor Positioning with Radio Location Fingerprinting

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    . A promising indoor positioning technique is radio-based location ngerprinting, having the major advantage of exploiting already existing radio infrastructures, like IEEE 802.11 or GSM, which avoids extra deployment costs and eort. The research goal of this thesis is to address the limitations of current...... indoor location ngerprinting systems. In particular the aim is to advance location ngerprinting techniques for the challenges of handling heterogeneous clients, scalability to many clients, and interference between communication and positioning. The wireless clients used for location ngerprinting...... are heterogeneous even when only considering clients for the same technology. The heterogeneity is due to dierent radios, antennas, and rmwares causing measurements for location ngerprinting not to be directly comparable among clients. Heterogeneity is a challenge for location ngerprinting because it severely...

  13. Optimal Hedge Tracking Portfolios in a Limit Order Book

    DEFF Research Database (Denmark)

    Ellersgaard, Simon; Tegner, Martin

    2017-01-01

    -optimizing option seller, who hedges his position using a combination of limit and market orders, while facing certain constraints as to how far he can deviate from a targeted (Bachelierian) delta strategy. By translating the control problem into a three-dimensional Hamilton–Jacobi–Bellman quasi......-variational inequality (HJB QVI) and solving numerically, we are able to deduce optimal limit order quotes alongside the regions surrounding the targeted delta surface in which the option seller must place limit orders vis-à-vis the more aggressive market orders. Our scheme is shown to be monotone, stable......, and consistent and thence, modulo a comparison principle, convergent in the viscosity sense....

  14. Automatic approach to deriving fuzzy slope positions

    Science.gov (United States)

    Zhu, Liang-Jun; Zhu, A.-Xing; Qin, Cheng-Zhi; Liu, Jun-Zhi

    2018-03-01

    Fuzzy characterization of slope positions is important for geographic modeling. Most of the existing fuzzy classification-based methods for fuzzy characterization require extensive user intervention in data preparation and parameter setting, which is tedious and time-consuming. This paper presents an automatic approach to overcoming these limitations in the prototype-based inference method for deriving fuzzy membership value (or similarity) to slope positions. The key contribution is a procedure for finding the typical locations and setting the fuzzy inference parameters for each slope position type. Instead of being determined totally by users in the prototype-based inference method, in the proposed approach the typical locations and fuzzy inference parameters for each slope position type are automatically determined by a rule set based on prior domain knowledge and the frequency distributions of topographic attributes. Furthermore, the preparation of topographic attributes (e.g., slope gradient, curvature, and relative position index) is automated, so the proposed automatic approach has only one necessary input, i.e., the gridded digital elevation model of the study area. All compute-intensive algorithms in the proposed approach were speeded up by parallel computing. Two study cases were provided to demonstrate that this approach can properly, conveniently and quickly derive the fuzzy slope positions.

  15. Real-time precision pedestrian navigation solution using Inertial Navigation System and Global Positioning System

    OpenAIRE

    Yong-Jin Yoon; King Ho Holden Li; Jiahe Steven Lee; Woo-Tae Park

    2015-01-01

    Global Positioning System and Inertial Navigation System can be used to determine position and velocity. A Global Positioning System module is able to accurately determine position without sensor drift, but its usage is limited in heavily urbanized environments and heavy vegetation. While high-cost tactical-grade Inertial Navigation System can determine position accurately, low-cost micro-electro-mechanical system Inertial Navigation System sensors are plagued by significant errors. Global Po...

  16. Patterns of positive selection in six Mammalian genomes

    DEFF Research Database (Denmark)

    Kosiol, Carolin; Vinar, Tomás; da Fonseca, Rute R

    2008-01-01

    Genome-wide scans for positively selected genes (PSGs) in mammals have provided insight into the dynamics of genome evolution, the genetic basis of differences between species, and the functions of individual genes. However, previous scans have been limited in power and accuracy owing to small...... several new lineage- and clade-specific tests to be applied. Of approximately 16,500 human genes with high-confidence orthologs in at least two other species, 400 genes showed significant evidence of positive selection (FDR... showed evidence of positive selection on particular lineages or clades. As in previous studies, the identified PSGs were enriched for roles in defense/immunity, chemosensory perception, and reproduction, but enrichments were also evident for more specific functions, such as complement-mediated immunity...

  17. A rhamnose-rich O-antigen mediates adhesion, virulence, and host colonization for the xylem-limited phytopathogen Xylella fastidiosa.

    Science.gov (United States)

    Clifford, Jennifer C; Rapicavoli, Jeannette N; Roper, M Caroline

    2013-06-01

    Xylella fastidiosa is a gram-negative, xylem-limited bacterium that causes a lethal disease of grapevine called Pierce's disease. Lipopolysaccharide (LPS) composes approximately 75% of the outer membrane of gram-negative bacteria and, because it is largely displayed on the cell surface, it mediates interactions between the bacterial cell and its surrounding environment. LPS is composed of a conserved lipid A-core oligosaccharide component and a variable O-antigen portion. By targeting a key O-antigen biosynthetic gene, we demonstrate the contribution of the rhamnose-rich O-antigen to surface attachment, cell-cell aggregation, and biofilm maturation: critical steps for successful infection of the host xylem tissue. Moreover, we have demonstrated that a fully formed O-antigen moiety is an important virulence factor for Pierce's disease development in grape and that depletion of the O-antigen compromises its ability to colonize the host. It has long been speculated that cell-surface polysaccharides play a role in X. fastidiosa virulence and this study confirms that LPS is a major virulence factor for this important agricultural pathogen.

  18. African Journal of Science and Technology (AJST) USE OF LIMITED ...

    African Journals Online (AJOL)

    Linear regression models for all stations show the expected strong positive association of ... streams in which flow rates are stochastic in nature. Effective flood ... Use of Limited Hydrological Data and Mathematical Parameters for Catchment.

  19. Lower limit of detection: definition and elaboration of a proposed position for radiological effluent and environmental measurements

    International Nuclear Information System (INIS)

    Currie, L.A.

    1984-09-01

    A manual is provided to define and illustrate a proposed use of the Lower Limit of Detection (LLD) for Radiological Effluent and Environmental Measurements. The manual contains a review of information regarding LLD practices gained from site visits; a review of the literature and a summary of basic principles underlying the concept of detection in Nuclear and Analytical Chemistry; a detailed presentation of the application of LLD principles to a range of problem categories (simple counting to multinuclide spectroscopy), including derivations, equations, and numerical examples; and a brief examination of related issues such as reference samples, numerical quality control, and instrumental limitations. An appendix contains a summary of notation and terminology, a bibliography, and worked-out examples. 100 references, 10 figures, 7 tables

  20. Current limitation by an electric double layer in ion laser discharges

    International Nuclear Information System (INIS)

    Torven, S.

    1977-12-01

    A theory for current limitation in ion laser discharges is investigated. The basic mechanism considered is saturation of the positive ion flux at an electric double layer by the limited flux of neutral atoms. The result is compared with a recently published synthesis of a large number of experimental data which agree well with those predicted by the double layer model

  1. Rigorous quantum limits on monitoring free masses and harmonic oscillators

    Science.gov (United States)

    Roy, S. M.

    2018-03-01

    There are heuristic arguments proposing that the accuracy of monitoring position of a free mass m is limited by the standard quantum limit (SQL): σ2( X (t ) ) ≥σ2( X (0 ) ) +(t2/m2) σ2( P (0 ) ) ≥ℏ t /m , where σ2( X (t ) ) and σ2( P (t ) ) denote variances of the Heisenberg representation position and momentum operators. Yuen [Phys. Rev. Lett. 51, 719 (1983), 10.1103/PhysRevLett.51.719] discovered that there are contractive states for which this result is incorrect. Here I prove universally valid rigorous quantum limits (RQL), viz. rigorous upper and lower bounds on σ2( X (t ) ) in terms of σ2( X (0 ) ) and σ2( P (0 ) ) , given by Eq. (12) for a free mass and by Eq. (36) for an oscillator. I also obtain the maximally contractive and maximally expanding states which saturate the RQL, and use the contractive states to set up an Ozawa-type measurement theory with accuracies respecting the RQL but beating the standard quantum limit. The contractive states for oscillators improve on the Schrödinger coherent states of constant variance and may be useful for gravitational wave detection and optical communication.

  2. Positive solutions for nonlocal dispersal equation with spatial degeneracy

    Science.gov (United States)

    Sun, Jian-Wen

    2018-02-01

    In this paper, we consider the positive solutions of the nonlocal dispersal equation \\int \\limits _{Ω }J(x,y)[u(y)-u(x)]dy=-λ m(x)u(x)+[c(x)+ɛ ]u^p(x) \\quad { in }\\bar{Ω }, where Ω \\subset R^N is a bounded domain, λ ,ɛ and p>1 are positive constants. The dispersal kernel J and the coefficient c( x) are nonnegative, but c( x) has a degeneracy in some subdomain of Ω . In order to study the influence of heterogeneous environment on the nonlocal system, we study the sharp spatial patterns of positive solutions as ɛ → 0. We obtain that the positive solutions always have blow-up asymptotic profiles in \\bar{Ω }. Meanwhile, we find that the profiles in degeneracy domain are different from the domain without degeneracy.

  3. The Nonverbal Communication of Positive Emotions: An Emotion Family Approach.

    Science.gov (United States)

    Sauter, Disa A

    2017-07-01

    This review provides an overview of the research on nonverbal expressions of positive emotions, organised into emotion families, that is, clusters sharing common characteristics. Epistemological positive emotions (amusement, relief, awe, and interest) are found to have distinct, recognisable displays via vocal or facial cues, while the agency-approach positive emotions (elation and pride) appear to be associated with recognisable visual, but not auditory, cues. Evidence is less strong for the prosocial emotions (love, compassion, gratitude, and admiration) in any modality other than touch, and there is little support for distinct recognisable signals of the savouring positive emotions (contentment, sensory pleasure, and desire). In closing, some limitations of extant work are noted and some proposals for future research are outlined.

  4. Determination of the upper limit of a peak area

    International Nuclear Information System (INIS)

    Helene, O.

    1990-03-01

    This paper reports the procedure to extract an upper limit of a peak area in a multichannel spectrum. This procedure takes into account the finite shape of the peak and the uncertanties in the background and in the expected position of the peak. (author) [pt

  5. Determination of the upper limit of a peak area

    International Nuclear Information System (INIS)

    Helene, O.

    1991-01-01

    This article reports the procedure to extract an upper limit of a peak area in a multichannel spectrum. This procedure takes into account the finite shape of the peak and the uncertainties both in the background and in the expected position of the peak. (orig.)

  6. Positive Association of Fibroadenomatoid Change with HER2-Negative Invasive Breast Cancer: A Co-Occurrence Study.

    Directory of Open Access Journals (Sweden)

    Yaqin Chen

    Full Text Available Risk assessment of a benign breast disease/lesion (BBD for invasive breast cancer (IBC is typically done through a longitudinal study. For an infrequently-reported BBD, the shortage of occurrence data alone is a limiting factor to conducting such a study. Here we present an approach based on co-occurrence analysis, to help address this issue. We focus on fibroadenomatoid change (FAC, an under-studied BBD, as our preliminary analysis has suggested its previously unknown significant co-occurrence with IBC.A cohort of 1667 female patients enrolled in the Clinical Breast Care Project was identified. A single experienced breast pathologist reviewed all pathology slides for each case and recorded all observed lesions, including FAC. Fibroadenoma (FA was studied for comparison since FAC had been speculated to be an immature FA. FA and Fibrocystic Changes (FCC were used for method validation since they have been comprehensively studied. Six common IBC and BBD risk/protective factors were also studied. Co-occurrence analyses were performed using logistic regression models.Common risk/protective factors were associated with FA, FCC, and IBC in ways consistent with the literature in general, and they were associated with FAC, FA, and FCC in distinct patterns. Age was associated with FAC in a bell-shape curve so that middle-aged women were more likely to have FAC. We report for the first time that FAC is positively associated with IBC with odds ratio (OR depending on BMI (OR = 6.78, 95%CI = 3.43-13.42 at BMI25 kg/m2. This association is only significant with HER2-negative IBC subtypes.We conclude that FAC is a candidate risk factor for HER2-negative IBCs, and it is a distinct disease from FA. Co-occurrence analysis can be used for initial assessment of the risk for IBC from a BBD, which is vital to the study of infrequently-reported BBDs.

  7. Positive Association of Fibroadenomatoid Change with HER2-Negative Invasive Breast Cancer: A Co-Occurrence Study

    Science.gov (United States)

    Kovatich, Albert J.; Hooke, Jeffrey A.; Liu, Jianfang; Kvecher, Leonid; Fantacone-Campbell, J. Leigh; Mitchell, Edith P.; Rui, Hallgeir; Shriver, Craig D.; Hu, Hai

    2015-01-01

    Background Risk assessment of a benign breast disease/lesion (BBD) for invasive breast cancer (IBC) is typically done through a longitudinal study. For an infrequently-reported BBD, the shortage of occurrence data alone is a limiting factor to conducting such a study. Here we present an approach based on co-occurrence analysis, to help address this issue. We focus on fibroadenomatoid change (FAC), an under-studied BBD, as our preliminary analysis has suggested its previously unknown significant co-occurrence with IBC. Methods A cohort of 1667 female patients enrolled in the Clinical Breast Care Project was identified. A single experienced breast pathologist reviewed all pathology slides for each case and recorded all observed lesions, including FAC. Fibroadenoma (FA) was studied for comparison since FAC had been speculated to be an immature FA. FA and Fibrocystic Changes (FCC) were used for method validation since they have been comprehensively studied. Six common IBC and BBD risk/protective factors were also studied. Co-occurrence analyses were performed using logistic regression models. Results Common risk/protective factors were associated with FA, FCC, and IBC in ways consistent with the literature in general, and they were associated with FAC, FA, and FCC in distinct patterns. Age was associated with FAC in a bell-shape curve so that middle-aged women were more likely to have FAC. We report for the first time that FAC is positively associated with IBC with odds ratio (OR) depending on BMI (OR = 6.78, 95%CI = 3.43-13.42 at BMI25 kg/m2). This association is only significant with HER2-negative IBC subtypes. Conclusions We conclude that FAC is a candidate risk factor for HER2-negative IBCs, and it is a distinct disease from FA. Co-occurrence analysis can be used for initial assessment of the risk for IBC from a BBD, which is vital to the study of infrequently-reported BBDs. PMID:26098961

  8. DOES POSITIONING HAVE A PLACE IN THE MINDS OF OUR STUDENTS?

    Directory of Open Access Journals (Sweden)

    Tatu Cristian Ionut

    2010-12-01

    Full Text Available Positioning is one of the most powerful marketing concepts. At the beginning, the meaning of positioning was rather limited, focusing on the concept of reputation. Then it became ”the place a brand occupies in the mind of its target audience”. Under this meaning , many companies have implemented the concept of positioning as a part of their everyday marketing activities. Nowadays, positioning is being used as a tool for explaining how consumers relate to foreign countries. The concept of positioning is simply to important to be ignored, but does it have a place in our students minds? This paper aims to determine whether we have an evolution or an involution in this matter.

  9. Optimising Mycobacterium tuberculosis detection in resource limited settings.

    Science.gov (United States)

    Alfred, Nwofor; Lovette, Lawson; Aliyu, Gambo; Olusegun, Obasanya; Meshak, Panwal; Jilang, Tunkat; Iwakun, Mosunmola; Nnamdi, Emenyonu; Olubunmi, Onuoha; Dakum, Patrick; Abimiku, Alash'le

    2014-03-03

    The light-emitting diode (LED) fluorescence microscopy has made acid-fast bacilli (AFB) detection faster and efficient although its optimal performance in resource-limited settings is still being studied. We assessed the optimal performances of light and fluorescence microscopy in routine conditions of a resource-limited setting and evaluated the digestion time for sputum samples for maximum yield of positive cultures. Cross-sectional study. Facility-based involving samples of routine patients receiving tuberculosis treatment and care from the main tuberculosis case referral centre in northern Nigeria. The study included 450 sputum samples from 150 new patients with clinical diagnosis of pulmonary tuberculosis. The 450 samples were pooled into 150 specimens, examined independently with mercury vapour lamp (FM), LED CysCope (CY) and Primo Star iLED (PiLED) fluorescence microscopies, and with the Ziehl-Neelsen (ZN) microscopy to assess the performance of each technique compared with liquid culture. The cultured specimens were decontaminated with BD Mycoprep (4% NaOH-1% NLAC and 2.9% sodium citrate) for 10, 15 and 20 min before incubation in Mycobacterium growth incubator tube (MGIT) system and growth examined for acid-fast bacilli (AFB). Of the 150 specimens examined by direct microscopy: 44 (29%), 60 (40%), 49 (33%) and 64 (43%) were AFB positive by ZN, FM, CY and iLED microscopy, respectively. Digestion of sputum samples for 10, 15 and 20 min yielded mycobacterial growth in 72 (48%), 81 (54%) and 68 (45%) of the digested samples, respectively, after incubation in the MGIT system. In routine laboratory conditions of a resource-limited setting, our study has demonstrated the superiority of fluorescence microscopy over the conventional ZN technique. Digestion of sputum samples for 15 min yielded more positive cultures.

  10. Positional Accuracy in Optical Trap-Assisted Nanolithography

    Science.gov (United States)

    Arnold, Craig B.; McLeod, Euan

    2009-03-01

    The ability to directly print patterns on size scales below 100 nm is important for many applications where the production or repair of high resolution and density features are important. Laser-based direct-write methods have the benefit of quickly and easily being able to modify and create structures on existing devices, but feature sizes are conventionally limited by diffraction. In this presentation, we show how to overcome this limit with a new method of probe-based near-field nanopatterning in which we employ a CW laser to optically trap and manipulate dispersed microspheres against a substrate using a 2-d Bessel beam optical trap. A secondary, pulsed nanosecond laser at 355 nm is directed through the bead and used to modify the surface below the microsphere, taking advantage of the near-field enhancement in order to produce materials modification with feature sizes under 100 nm. Here, we analyze the 3-d positioning accuracy of the microsphere through analytic modeling as a function of experimental parameters. The model is verified in all directions for our experimental conditions and is used to predict the conditions required for improved positional accuracy.

  11. Positive psychology interventions in breast cancer. A systematic review.

    Science.gov (United States)

    Casellas-Grau, Anna; Font, Antoni; Vives, Jaume

    2014-01-01

    Positive psychology is an emerging area of empirical study, not only in clinical, but also in health psychology. The present systematic review aims to synthesize the evidence about the positive psychology interventions utilized in breast cancer. Relevant studies were identified via Pubmed, PsycINFO, Web of Science, Scopus, Cochrane, CINAHL, Wiley Online Library, TDX, and DIALNET databases (up to April 2013). Only those papers focused on interventions related to positive psychology and carried out on breast cancer patients were included. Of the 7266 articles found through databases, 16 studies were finally included in this review. Five groups of therapies were found: mindfulness-based approaches, expression of positive emotions, spiritual interventions, hope therapy, and meaning-making interventions. These specific interventions promoted positive changes in breast cancer participants, such as enhanced quality of life, well-being, hope, benefit finding, or optimism. However, the disparity of the interventions and some methodological issues limit the outcomes. Some studies provided relevant evidence about the clear development of positive aspects from the breast cancer experience. Positive interventions applied to patients and survivors of breast cancer were found to be able to promote positive aspects. A global consensus of a positive therapies classification is needed to take one more step in structuring positive psychology. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Forward and correctional OFDM-based visible light positioning

    Science.gov (United States)

    Li, Wei; Huang, Zhitong; Zhao, Runmei; He, Peixuan; Ji, Yuefeng

    2017-09-01

    Visible light positioning (VLP) has attracted much attention in both academic and industrial areas due to the extensive deployment of light-emitting diodes (LEDs) as next-generation green lighting. Generally, the coverage of a single LED lamp is limited, so LED arrays are always utilized to achieve uniform illumination within the large-scale indoor environment. However, in such dense LED deployment scenario, the superposition of the light signals becomes an important challenge for accurate VLP. To solve this problem, we propose a forward and correctional orthogonal frequency division multiplexing (OFDM)-based VLP (FCO-VLP) scheme with low complexity in generating and processing of signals. In the first forward procedure of FCO-VLP, an initial position is obtained by the trilateration method based on OFDM-subcarriers. The positioning accuracy will be further improved in the second correctional procedure based on the database of reference points. As demonstrated in our experiments, our approach yields an improved average positioning error of 4.65 cm and an enhanced positioning accuracy by 24.2% compared with trilateration method.

  13. A COMPARATIVE ANALYSIS OF GLOBAL POSITIONING SYSTEM SCHEMES BASED ON BLOCK CODES

    OpenAIRE

    Prasad Janga; Dr. R. L. Sharma

    2017-01-01

    Global Positioning System (GPS) is a satellite based positioning system based on radio ranging technique. The GPS will provide very accurate three-dimensional position, velocity and timing information to users anywhere in the world. GPS can also be used in other applications such as vehicle monitoring for traffic management in urban areas, Geographical Information System (GIS), 4G Communications, marine navigation, search and rescue and military applications. As GPS accuracy is limited by ion...

  14. An experimental study of the effect of green positioning on brand attitude

    OpenAIRE

    PATRIK HARTMANN; VANESSA APAOLAZA IBÁÑEZ; F. JAVIER FORCADA SAIZ

    2004-01-01

    Reducing the environmental impact of a product or its manufacturing process not necessarily limits the company’s activities. In the context of a green branding strategy, it might as well open new business opportunities. Ecological positioning provides a strategic tool for the active implementation of green brands. The empirical study shows that more positive attitudes are developed towards a brand positioned by environmental attributes and that these effects vary as a result of the implementa...

  15. Quantitative risk stratification in Markov chains with limiting conditional distributions.

    Science.gov (United States)

    Chan, David C; Pollett, Philip K; Weinstein, Milton C

    2009-01-01

    Many clinical decisions require patient risk stratification. The authors introduce the concept of limiting conditional distributions, which describe the equilibrium proportion of surviving patients occupying each disease state in a Markov chain with death. Such distributions can quantitatively describe risk stratification. The authors first establish conditions for the existence of a positive limiting conditional distribution in a general Markov chain and describe a framework for risk stratification using the limiting conditional distribution. They then apply their framework to a clinical example of a treatment indicated for high-risk patients, first to infer the risk of patients selected for treatment in clinical trials and then to predict the outcomes of expanding treatment to other populations of risk. For the general chain, a positive limiting conditional distribution exists only if patients in the earliest state have the lowest combined risk of progression or death. The authors show that in their general framework, outcomes and population risk are interchangeable. For the clinical example, they estimate that previous clinical trials have selected the upper quintile of patient risk for this treatment, but they also show that expanded treatment would weakly dominate this degree of targeted treatment, and universal treatment may be cost-effective. Limiting conditional distributions exist in most Markov models of progressive diseases and are well suited to represent risk stratification quantitatively. This framework can characterize patient risk in clinical trials and predict outcomes for other populations of risk.

  16. Culture-positive sepsis in neonatal camelids: 21 cases.

    Science.gov (United States)

    Dolente, Brett A; Lindborg, Susan; Palmer, Jonathan E; Wilkins, Pamela A

    2007-01-01

    There is limited literature on neonatal bacterial sepsis in New World (NW) camelids. Bacterial culture-positive crias have clinical differences based on the specific bacterial genera isolated. Bacterial culture-positive NW camelid crias blood gas abnormalities, potentially complicating diagnosis. Affected crias may not have localizing signs at presentation and are not usually febrile, although hypothermia, tachypnea, and tachycardia are relatively common. Total protein concentration was not a substitute for immunoglobulin G measurement in septic crias in this study. Familiarity with the clinical presentation and common pathogens isolated should improve early recognition and treatment and ultimately outcome of crias with sepsis.

  17. Perceived health in lung cancer patients: the role of positive and negative affect.

    Science.gov (United States)

    Hirsch, Jameson K; Floyd, Andrea R; Duberstein, Paul R

    2012-03-01

    To examine the association of affective experience and health-related quality of life in lung cancer patients, we hypothesized that negative affect would be positively, and positive affect would be negatively, associated with perceived health. A sample of 133 English-speaking lung cancer patients (33% female; mean age = 63.68 years old, SD = 9.37) completed a battery of self-report surveys. Results of our secondary analysis indicate that trait negative affect was significantly associated with poor physical and social functioning, greater role limitations due to emotional problems, greater bodily pain, and poor general health. Positive affect was significantly associated with adaptive social functioning, fewer emotion-based role limitations, and less severe bodily pain. In a full model, positive affect was significantly associated with greater levels of social functioning and general health, over and above the effects of negative affect. Reduction of negative affect is an important therapeutic goal, but the ability to maintain positive affect may result in greater perceived health. Indeed, engagement in behaviors that result in greater state positive affect may, over time, result in dispositional changes and enhancement of quality of life.

  18. The neglected role of positive emotion in adolescent psychopathology.

    Science.gov (United States)

    Gilbert, Kirsten E

    2012-08-01

    Adolescence is a developmental period characterized by elevated stress, heightened risky behaviors, and increases in psychopathology. Emotion dysregulation is a hypothesized contributor to negative outcomes and to the onset of psychopathology during adolescence. However, the dysregulation of negative emotion has been the focus of research while the literature on positive emotion in adolescent psychopathology is limited. This review highlights both the development of normative and dysregulated positive emotion during adolescence. First, the literature on normative adolescent emotional development and on negative emotional regulation is briefly reviewed, followed by a discussion of current theories of positive emotion, which are grounded in the adult literature. From a developmental perspective, the dimension of approach motivation within positive emotion is emphasized throughout and frames the review. This conceptualization guides organization of literatures on normative experiences of positive emotion in adolescence and the role of dysregulated positive emotion in adolescent psychopathology, specifically adolescent depression, anxiety, bipolar disorder, externalizing disorders and eating disorders. Last, future directions in the study of adolescent positive emotion and its regulation and the implications of highlighting approach motivation in normative and dysregulated positive emotion in adolescence are detailed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Mouse models of estrogen receptor-positive breast cancer

    Directory of Open Access Journals (Sweden)

    Shakur Mohibi

    2011-01-01

    Full Text Available Breast cancer is the most frequent malignancy and second leading cause of cancer-related deaths among women. Despite advances in genetic and biochemical analyses, the incidence of breast cancer and its associated mortality remain very high. About 60 - 70% of breast cancers are Estrogen Receptor alpha (ER-α positive and are dependent on estrogen for growth. Selective estrogen receptor modulators (SERMs have therefore provided an effective targeted therapy to treat ER-α positive breast cancer patients. Unfortunately, development of resistance to endocrine therapy is frequent and leads to cancer recurrence. Our understanding of molecular mechanisms involved in the development of ER-α positive tumors and their resistance to ER antagonists is currently limited due to lack of experimental models of ER-α positive breast cancer. In most mouse models of breast cancer, the tumors that form are typically ER-negative and independent of estrogen for their growth. However, in recent years more attention has been given to develop mouse models that develop different subtypes of breast cancers, including ER-positive tumors. In this review, we discuss the currently available mouse models that develop ER-α positive mammary tumors and their potential use to elucidate the molecular mechanisms of ER-α positive breast cancer development and endocrine resistance.

  20. Change of position of constitutional judiciary

    Directory of Open Access Journals (Sweden)

    Orlović Slobodan P.

    2013-01-01

    Full Text Available Constitutional judiciary is the youngest branch of authority in the horizontal level of state power. Constitutional judiciary has, during its existence - during two centuries as an ordinary court and during one century as a special authority, changed its position, role and importance. Those characteristics of constitutional judiciary had an increasing way - the position became better, in political and law sense, its role has expanded and the importance has increased. Today, constitutional judiciary is an inevitable subject of constitutional regimes in huge number of states (between them are almost all federations but, in the same time, constitutional judiciary is an authority which is at least limited by the constitution. The constitution is "soft" to the constitutional judiciary because the judiciary interpreted the constitution in accordance to its political and law attitudes, hidden by the guise of protection. Different separation of power, a rise of executive power, requests for better protections of fundamental human rights, a changed role of state and executive power, altogether, have influenced to change of position of constitutional judiciary.

  1. Difficulties in emotion regulation mediate negative and positive affects and craving in alcoholic patients.

    Science.gov (United States)

    Khosravani, Vahid; Sharifi Bastan, Farangis; Ghorbani, Fatemeh; Kamali, Zoleikha

    2017-08-01

    The aim of this study was to assess the mediating effects of difficulties in emotion regulation (DER) on the relations of negative and positive affects to craving in alcoholic patients. 205 treatment-seeking alcoholic outpatients were included. DER, positive and negative affects as well as craving were evaluated by the Difficulties in Emotion Regulation Scale (DERS), the Positive/Negative Affect Scales, and the Obsessive Compulsive Drinking Scale (OCDS) respectively. Clinical factors including depression and severity of alcohol dependence were investigated by the Alcohol Use Disorders Identification Test (AUDIT) and the Beck Depression Inventory-II (BDI-II) respectively. Results revealed that both increased negative affect and decreased positive affect indirectly influenced craving through limited access to emotion regulation strategies. It was concluded that limited access to emotion regulation strategies may be important in predicting craving for alcoholics who experience both increased negative affect and decreased positive affect. This suggests that treatment and prevention efforts focused on increasing positive affect, decreasing negative affect and teaching effective regulation strategies may be critical in reducing craving in alcoholic patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Limitations to private properties in the vicinity of nuclear power plants

    International Nuclear Information System (INIS)

    Martini, L.E.

    1978-01-01

    This study, based on Argentine legislation, analyses the limitations to private property in the surroundings of nuclear power plants, due to public interest. A nuclear power plant could demand different kinds of property limitation, that could vary from restrictions to the absolute nature of property, to expropriation. Limitation of property is a different concept from restriction of property, the concept of limitation is wider. The author analyses for both concepts: validy requirements, competent bodies, and jurisdiction in case of conflict. He also explains the conditions and process of expropriation. Article 14 of the Constitution constitutes the positive legal basis for limitations of property. In the hypotheses of limitations to property due to vicinity of nuclear power plants, national legislation takes precedence over provincial law, since it is a matter of public national interest. (author)

  3. Quantum limit on time measurement in a gravitational field

    International Nuclear Information System (INIS)

    Sinha, Supurna; Samuel, Joseph

    2015-01-01

    Good clocks are of importance both to fundamental physics and for applications in astronomy, metrology and global positioning systems. In a recent technological breakthrough, researchers at NIST have been able to achieve a stability of one part in 10 18 using an ytterbium clock. This naturally raises the question of whether there are fundamental limits to time keeping. In this article we point out that gravity and quantum mechanics set a fundamental limit on the fractional frequency uncertainty of clocks. This limit comes from a combination of the uncertainty relation, the gravitational redshift and the relativistic time dilation effect. For example, a single ion aluminium clock in a terrestrial gravitational field cannot achieve a fractional frequency uncertainty better than one part in 10 22 . This fundamental limit explores the interaction between gravity and quantum mechanics on a laboratory scale. (paper)

  4. Comparison of WDM/Pulse-Position-Modulation (WDM/PPM) with Code/Pulse-Position-Swapping (C/PPS) Based on Wavelength/Time Codes

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2009-06-19

    Pulse position modulation (PPM) signaling is favored in intensity modulated/direct detection (IM/DD) systems that have average power limitations. Combining PPM with WDM over a fiber link (WDM/PPM) enables multiple accessing and increases the link's throughput. Electronic bandwidth and synchronization advantages are further gained by mapping the time slots of PPM onto a code space, or code/pulse-position-swapping (C/PPS). The property of multiple bits per symbol typical of PPM can be combined with multiple accessing by using wavelength/time [W/T] codes in C/PPS. This paper compares the performance of WDM/PPM and C/PPS for equal wavelengths and bandwidth.

  5. Radio-frequency electromagnetic field (RF-EMF) exposure levels in different European outdoor urban environments in comparison with regulatory limits.

    Science.gov (United States)

    Urbinello, Damiano; Joseph, Wout; Huss, Anke; Verloock, Leen; Beekhuizen, Johan; Vermeulen, Roel; Martens, Luc; Röösli, Martin

    2014-07-01

    Concerns of the general public about potential adverse health effects caused by radio-frequency electromagnetic fields (RF-EMFs) led authorities to introduce precautionary exposure limits, which vary considerably between regions. It may be speculated that precautionary limits affect the base station network in a manner that mean population exposure unintentionally increases. The objectives of this multicentre study were to compare mean exposure levels in outdoor areas across four different European cities and to compare with regulatory RF-EMF exposure levels in the corresponding areas. We performed measurements in the cities of Amsterdam (the Netherlands, regulatory limits for mobile phone base station frequency bands: 41-61 V/m), Basel (Switzerland, 4-6 V/m), Ghent (Belgium, 3-4.5 V/m) and Brussels (Belgium, 2.9-4.3 V/m) using a portable measurement device. Measurements were conducted in three different types of outdoor areas (central and non-central residential areas and downtown), between 2011 and 2012 at 12 different days. On each day, measurements were taken every 4s for approximately 15 to 30 min per area. Measurements per urban environment were repeated 12 times during 1 year. Arithmetic mean values for mobile phone base station exposure ranged between 0.22 V/m (Basel) and 0.41 V/m (Amsterdam) in all outdoor areas combined. The 95th percentile for total RF-EMF exposure varied between 0.46 V/m (Basel) and 0.82 V/m (Amsterdam) and the 99th percentile between 0.81 V/m (Basel) and 1.20 V/m (Brussels). All exposure levels were far below international reference levels proposed by ICNIRP (International Commission on Non-Ionizing Radiation Protection). Our study did not find indications that lowering the regulatory limit results in higher mobile phone base station exposure levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Weak limits for quantum random walks

    International Nuclear Information System (INIS)

    Grimmett, Geoffrey; Janson, Svante; Scudo, Petra F.

    2004-01-01

    We formulate and prove a general weak limit theorem for quantum random walks in one and more dimensions. With X n denoting position at time n, we show that X n /n converges weakly as n→∞ to a certain distribution which is absolutely continuous and of bounded support. The proof is rigorous and makes use of Fourier transform methods. This approach simplifies and extends certain preceding derivations valid in one dimension that make use of combinatorial and path integral methods

  7. Reliability-based dynamic positioning of floating vessels with riser and mooring system

    DEFF Research Database (Denmark)

    Fang, Shaoji; Leira, Bernt J.; Blanke, Mogens

    2011-01-01

    To maintain safety of a floating vessel with associated slender components such as risers and mooring line, the vessel is normally kept within a limited region. To specify a safe position in that region, this paper suggests a new position chasing algorithm with the consideration of both riser ang...... to their criticality. An optimal position set-point is produced by minimization of the value of the cost function. Numerical simulations show the effectiveness of the proposed algorithm....

  8. Lateral positioning for critically ill adult patients.

    Science.gov (United States)

    Hewitt, Nicky; Bucknall, Tracey; Faraone, Nardene M

    2016-05-12

    lateral positioning in critically ill adults. We included manual or automated turns but limited eligibility to studies that included duration of body position of 10 minutes or longer. We examined each lateral position versus at least one comparator (opposite lateral position and/or another body position) for single therapy effects, and the lateral positioning schedule (repeated lateral turning) versus other positioning schedules for repetitive therapy effects. We pre-specified methods to be used for data collection, risk of bias assessment and analysis. Two independent review authors carried out each stage of selection and data extraction and settled differences in opinion by consensus, or by third party adjudication when disagreements remained unresolved. We planned analysis of pair-wise comparisons under composite time intervals with the aim of considering recommendations based on meta-analyses of studies with low risk of bias. We included 24 studies of critically ill adults. No study reported mortality as an outcome of interest. Two randomized controlled trials (RCTs) examined lateral positioning for pulmonary morbidity outcomes but provided insufficient information for meta-analysis. A total of 22 randomized trials examined effects of lateral positioning (four parallel-group and 18 cross-over designs) by measuring various continuous data outcomes commonly used to detect adverse cardiopulmonary events within critical care areas. However, parallel-group studies were not comparable, and cross-over studies provided limited data as the result of unit of analysis errors. Eight studies provided some data; most of these were single studies with small effects that were imprecise. We pooled partial pressure of arterial oxygen (PaO2) as a measure to detect hypoxaemia from two small studies of participants with unilateral lung disease (n = 19). The mean difference (MD) between lateral positions (bad lung down versus good lung down) was approximately 50 mmHg (MD -49.26 mmHg, 95

  9. Recursive integral equations with positive kernel for lattice calculations

    International Nuclear Information System (INIS)

    Illuminati, F.; Isopi, M.

    1990-11-01

    A Kirkwood-Salzburg integral equation, with positive defined kernel, for the states of lattice models of statistical mechanics and quantum field theory is derived. The equation is defined in the thermodynamic limit, and its iterative solution is convergent. Moreover, positivity leads to an exact a priori bound on the iteration. The equation's relevance as a reliable algorithm for lattice calculations is therefore suggested, and it is illustrated with a simple application. It should provide a viable alternative to Monte Carlo methods for models of statistical mechanics and lattice gauge theories. 10 refs

  10. Quantum speed limits in open system dynamics.

    Science.gov (United States)

    del Campo, A; Egusquiza, I L; Plenio, M B; Huelga, S F

    2013-02-01

    Bounds to the speed of evolution of a quantum system are of fundamental interest in quantum metrology, quantum chemical dynamics, and quantum computation. We derive a time-energy uncertainty relation for open quantum systems undergoing a general, completely positive, and trace preserving evolution which provides a bound to the quantum speed limit. When the evolution is of the Lindblad form, the bound is analogous to the Mandelstam-Tamm relation which applies in the unitary case, with the role of the Hamiltonian being played by the adjoint of the generator of the dynamical semigroup. The utility of the new bound is exemplified in different scenarios, ranging from the estimation of the passage time to the determination of precision limits for quantum metrology in the presence of dephasing noise.

  11. Practical roadmap and limits to nanostructured photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lunt, Richard R. [Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824 (United States); Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Osedach, Timothy P. [School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138 (United States); Brown, Patrick R. [Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Rowehl, Jill A. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Bulovic, Vladimir [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2011-12-22

    The significant research interest in the engineering of photovoltaic (PV) structures at the nanoscale is directed toward enabling reductions in PV module fabrication and installation costs as well as improving cell power conversion efficiency (PCE). With the emergence of a multitude of nanostructured photovoltaic (nano-PV) device architectures, the question has arisen of where both the practical and the fundamental limits of performance reside in these new systems. Here, the former is addressed a posteriori. The specific challenges associated with improving the electrical power conversion efficiency of various nano-PV technologies are discussed and several approaches to reduce their thermal losses beyond the single bandgap limit are reviewed. Critical considerations related to the module lifetime and cost that are unique to nano-PV architectures are also addressed. The analysis suggests that a practical single-junction laboratory power conversion efficiency limit of 17% and a two-cell tandem power conversion efficiency limit of 24% are possible for nano-PVs, which, when combined with operating lifetimes of 10 to 15 years, could position them as a transformational technology for solar energy markets. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Bioethical Considerations for Teachers of the Severe and Profoundly Retarded: A Position Paper.

    Science.gov (United States)

    Downie, Don; Snart, Fern

    1983-01-01

    The paper reviews bioethical positions regarding the "human-ness" of severely handicapped students, notes that the quality of life for many severely handicapped persons is directly threatened by the utilitarian position which questions the personhood of individuals with limited IQ, and asserts that the deontological postition is more aligned with…

  13. Positive emotions, spirituality and the practice of psychiatry.

    Science.gov (United States)

    Vaillant, George E

    2008-01-01

    THIS PAPER PROPOSES THAT EIGHT POSITIVE EMOTIONS: awe, love (attachment), trust (faith), compassion, gratitude, forgiveness, joy and hope constitute what we mean by spirituality. These emotions have been grossly ignored by psychiatry. The two sciences that I shall employ to demonstrate this definition of spirituality will be ethology and neuroscience. They are both very new. I will argue that spirituality is not about ideas, sacred texts and theology; rather, spirituality is all about emotion and social connection.Specific religions, for all their limitations, are often the portal through which positive emotions are brought into conscious attention. Neither Freud nor psychiatric textbooks ever mention emotions like joy and gratitude. Hymns and psalms give these emotions pride of place. Our whole concept of psychotherapy might change if clinicians set about enhancing positive emotions rather than focusing only on negative emotions.

  14. Gas and electric power opening of the markets. Reality, limits and paradoxes the position of the cogeneration; Gaz electricite ouverture des marches. Realite, limites et paradoxes place de la cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    During these two days of the colloquium on gas and electric power market opening, industrial and french administration discussed about the new market deregulation impacts and the cogeneration position in this context. The position of EDF and Gaz De France, the european competition and the government policy are presented. These nineteen papers proposed an economic analysis and the state of the art of the situation. (A.L.B.)

  15. Possibilities and Limits of Religion in the Cyberspace of Digital Media

    Directory of Open Access Journals (Sweden)

    Slavomír Gálik

    2017-06-01

    Full Text Available The authors of this paper study possibilities and limits of religion in the cyberspace of digital media, especially in the World of Warcraft videogame. Basing on various research cases, they claim that videogames can saturate religious needs of the hypermodern human. Nevertheless, they cannot substitute them totally, since there is the humans’ body, a barrier between virtual and traditional religion. In the first case (the so-called external limitation, the body is irreplaceable in religious ritual such as Baptising in Christian religion or Mindfulness of Breathing (ānāpānasati in Buddhism. In the second case (the so-called internal limitation, when the body (or its nerve centre is linked to technologies, the boundary lies in the depth and validity of spiritual experience. The authors state that even if positive cyber-spiritual experience could be reached, it would still be necessary to plant it into broader moral and cognitive frames. Only in such case it could represent a positive stimulus for the spiritual journey.

  16. Impulse position control algorithms for nonlinear systems

    Energy Technology Data Exchange (ETDEWEB)

    Sesekin, A. N., E-mail: sesekin@list.ru [Ural Federal University, 19 S. Mira, Ekaterinburg, 620002 (Russian Federation); Institute of Mathematics and Mechanics, Ural Division of Russian Academy of Sciences, 16 S. Kovalevskaya, Ekaterinburg, 620990 (Russian Federation); Nepp, A. N., E-mail: anepp@urfu.ru [Ural Federal University, 19 S. Mira, Ekaterinburg, 620002 (Russian Federation)

    2015-11-30

    The article is devoted to the formalization and description of impulse-sliding regime in nonlinear dynamical systems that arise in the application of impulse position controls of a special kind. The concept of trajectory impulse-sliding regime formalized as some limiting network element Euler polygons generated by a discrete approximation of the impulse position control This paper differs from the previously published papers in that it uses a definition of solutions of systems with impulse controls, it based on the closure of the set of smooth solutions in the space of functions of bounded variation. The need for the study of such regimes is the fact that they often arise when parry disturbances acting on technical or economic control system.

  17. Impulse position control algorithms for nonlinear systems

    Science.gov (United States)

    Sesekin, A. N.; Nepp, A. N.

    2015-11-01

    The article is devoted to the formalization and description of impulse-sliding regime in nonlinear dynamical systems that arise in the application of impulse position controls of a special kind. The concept of trajectory impulse-sliding regime formalized as some limiting network element Euler polygons generated by a discrete approximation of the impulse position control This paper differs from the previously published papers in that it uses a definition of solutions of systems with impulse controls, it based on the closure of the set of smooth solutions in the space of functions of bounded variation. The need for the study of such regimes is the fact that they often arise when parry disturbances acting on technical or economic control system.

  18. Limitations of the RAPD technique in phylogeny reconstruction in Drosophila

    NARCIS (Netherlands)

    van de Zande, Louis; Bijlsma, R.

    In this study the limitations of the RAPD technique for phylogenetic analysis of very closely related and less related species of Drosophila are examined. In addition, assumptions of positional homology of amplified fragments in different species are examined by cross-hybridization of RAPD

  19. A labview approach to instrumentation for the TFTR bumper limiter alignment project

    International Nuclear Information System (INIS)

    Skelly, G.N.; Owens, D.K.

    1992-01-01

    This paper reports on a project recently undertaken to measure the alignment of the TFTR bumper limiter in relation to the toroidal magnetic field axis. The process involved the measurement of the toroidal magnetic field, and the positions of the tiles that make up the bumper limiter. The basis for the instrument control and data acquisition system was National Instrument's LabVIEW 2. LabVIEW is a graphical programming system for developing scientific and engineering applications on a Macintosh. For this project, a Macintosh IIci controlled the IEEE-488 GPIB programmable instruments via an interface box connected to the SCSI port of the computer. With LabVIEW, users create graphical software modules called virtual instruments instead of writing conventional text-based code. To measure the magnetic field, the control system acquired data from two nuclear magnetic resonance magnetometers while the torroidal field coils were pulsed. To measure the position of the tiles on the limiter, an instrumented mechanical arm was used inside the vessel

  20. Design of exceptionally strong and conductive Cu alloys beyond the conventional speculation via the interfacial energy-controlled dispersion of γ-Al2O3 nanoparticles.

    Science.gov (United States)

    Han, Seung Zeon; Kim, Kwang Ho; Kang, Joonhee; Joh, Hongrae; Kim, Sang Min; Ahn, Jee Hyuk; Lee, Jehyun; Lim, Sung Hwan; Han, Byungchan

    2015-11-30

    The development of Cu-based alloys with high-mechanical properties (strength, ductility) and electrical conductivity plays a key role over a wide range of industrial applications. Successful design of the materials, however, has been rare due to the improvement of mutually exclusive properties as conventionally speculated. In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled. We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes. It is shown that the Ti dramatically drives the interfacial phase transformation from very irregular to homogeneous spherical morphologies resulting in substantial enhancement of the mechanical property of Cu matrix. Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu. We validate experimental results using TEM and EDX combined with first-principles density functional theory (DFT) calculations, which all consistently poise that our materials are suitable for industrial applications.

  1. Homeless Adolescents' Perceptions of Positive Development: A Comparative Study

    Science.gov (United States)

    Nott, Brooke Dolenc; Vuchinich, Samuel

    2016-01-01

    Background: While some recent research has addressed homeless youth from a strengths-based approach, comparative studies of homeless and non-homeless youth from a strengths perspective are few; research that includes youth's views on positive youth development are also limited. Objective: Addressing these gaps and using an inductive approach,…

  2. Football Players' Head-Impact Exposure After Limiting of Full-Contact Practices.

    Science.gov (United States)

    Broglio, Steven P; Williams, Richelle M; O'Connor, Kathryn L; Goldstick, Jason

    2016-07-01

    Sporting organizations limit full-contact football practices to reduce concussion risk and based on speculation that repeated head impacts may result in long-term neurodegeneration. To directly compare head-impact exposure in high school football players before and after a statewide restriction on full-contact practices. Cross-sectional study. High school football field. Participants were varsity football athletes from a single high school. Before the rule change, 26 athletes (age = 16.2 ± 0.8 years, height = 179.6 ± 6.4 cm, weight = 81.9 ± 13.1 kg) participated. After the rule change, 24 athletes (age = 15.9 ± 0.8 years, height = 178.3 ± 6.5 cm, weight = 76.2 ± 11.6 kg) participated. Nine athletes participated in both years of the investigation. Head-impact exposure was monitored using the Head Impact Telemetry System while the athletes participated in football games and practices in the seasons before and after the rule change. Head-impact frequency, location, and magnitude (ie, linear acceleration, rotational acceleration, and Head Impact Telemetry severity profile [HITsp], respectively) were measured. A total of 15 398 impacts (592 impacts per player per season) were captured before the rule change and 8269 impacts (345 impacts per player per season) after the change. An average 42% decline in impact exposure occurred across all players, with practice-exposure declines occurring among linemen (46% decline); receivers, cornerbacks, and safeties (41% decline); and tight ends, running backs (including fullbacks), and linebackers (39% decline). Impact magnitudes remained largely unchanged between the years. A rule change limiting full-contact high school football practices appears to have been effective in reducing head-impact exposure across all players, with the largest reduction occurring among linemen. This finding is likely associated with the rule modification, particularly because the coaching staff and offensive scheme remained consistent, yet how

  3. Parallel arrangements of positive feedback loops limit cell-to-cell variability in differentiation.

    Science.gov (United States)

    Dey, Anupam; Barik, Debashis

    2017-01-01

    Cellular differentiations are often regulated by bistable switches resulting from specific arrangements of multiple positive feedback loops (PFL) fused to one another. Although bistability generates digital responses at the cellular level, stochasticity in chemical reactions causes population heterogeneity in terms of its differentiated states. We hypothesized that the specific arrangements of PFLs may have evolved to minimize the cellular heterogeneity in differentiation. In order to test this we investigated variability in cellular differentiation controlled either by parallel or serial arrangements of multiple PFLs having similar average properties under extrinsic and intrinsic noises. We find that motifs with PFLs fused in parallel to one another around a central regulator are less susceptible to noise as compared to the motifs with PFLs arranged serially. Our calculations suggest that the increased resistance to noise in parallel motifs originate from the less sensitivity of bifurcation points to the extrinsic noise. Whereas estimation of mean residence times indicate that stable branches of bifurcations are robust to intrinsic noise in parallel motifs as compared to serial motifs. Model conclusions are consistent both in AND- and OR-gate input signal configurations and also with two different modeling strategies. Our investigations provide some insight into recent findings that differentiation of preadipocyte to mature adipocyte is controlled by network of parallel PFLs.

  4. The Yuan vs. the Dollar: China and the United States are Already in a Hot War

    Science.gov (United States)

    2005-05-19

    HotWar is named as such because it is a money-centric conflict where speculative money (Le., "Hof’ money in FOREX )reigns as an instrument of economic and...exchange ( FOREX ) market. Here, the USD valiantly attempts to defend its reserved position in the world, while it is dragged into collisions with the...the two nations; rather, the value ofthese two currencies, which perennially draw speculative (i.e., "hot") money in the FOREX markets, is the

  5. Analysis of Links Positions in Landing Gear Mechanism

    Science.gov (United States)

    Brewczyński, D.; Tora, G.

    2014-08-01

    This article contains a kinematic analysis of an aircraft chassis mechanism in a range of positions. The mechanism of the chassis is made up of several smaller subsystems with different functions. The first mechanism is used to eject the chassis before landing (touchdown) and fold it to hatchway after the lift off. The second mechanism is designed to perform rotation of the crossover with the wheel, in order to adjust the position of the wheel to fit it in the limited space in the hold. The third mechanism allows movement of the chassis resulting from the change in length of the damper. To determine the position of the following links of the mechanism calculus of vectors was applied in which unit vectors were used to represent the angular position of the links. The aim of the analysis is to determine the angle of convergence and the angle of heel wheels as a function of the variable length of hydraulic cylinder, length of the shock absorber, length of the regulations rods

  6. Position sensitive proportional counters as focal plane detectors

    International Nuclear Information System (INIS)

    Ford, J.L.C. Jr.

    1979-01-01

    The rise time and charge division techniques for position decoding with RC-line proportional counters are reviewed. The advantages that these detectors offer as focal plane counters for nuclear spectroscopy performed with magnetic spectrographs are discussed. The theory of operation of proportional counters as position sensing devices is summarized, as well as practical aspects affecting their application. Factors limiting the position and energy resolutions obtainable with a focal plane proportional counter are evaluated and measured position and energy loss values are presented for comparison. Detector systems capable of the multiparameter measurements required for particle identification, background suppression and ray-tracing are described in order to illustrate the wide applicability of proportional counters within complex focal plane systems. Examples of the use of these counters other than with magnetic spectrographs are given in order to demonstrate their usefulness in not only nuclear physics but also in fields such as solid state physics, biology, and medicine. The influence of the new focal plane detector systems on future magnetic spectrograph designs is discussed. (Auth.)

  7. Effects of the location of a biased limiter on turbulent transport in the IR-T1 tokamak plasma

    International Nuclear Information System (INIS)

    Alipour, R.; Ghoranneviss, M.; Salar Elahi, A.; Meshkani, S.

    2017-01-01

    Plasma confinement plays an important role in fusion study. Applying an external voltage using limiter biasing system is proved to be an efficient approach for plasma confinement. In this study, the position of the limiter biasing system was changed to investigate the effect of applying external voltages at different places to the plasma. The external voltages of ±200 V were applied at the different positions of edge, 5 mm and 10 mm inside the plasma. Then, the main plasma parameters were measured. The results show that the poloidal turbulent transport and radial electric field increased about 25-35% and 35-45%, respectively (specially when the limiter biasing system was placed 5 mm inside the plasma). Also, the Reynolds stress has experienced its maximum reduction about 5-10% when the limiter biasing system was at 5 mm inside the plasma and the voltage of +200 V was applied to the plasma. When the limiter biasing system move 10 mm inside the plasma, the main plasma parameters experienced more instabilities and fluctuations than other positions. (authors)

  8. 76 FR 4751 - Position Limits for Derivatives

    Science.gov (United States)

    2011-01-26

    ... saleable by long traders at its market value in normal cash marketing channels at the derivative contract's... Association, Futures Industry Association, GDF Suez Energy, Morgan Stanley, and NextEra Energy Power Marketing...

  9. Large acoustic solitons and double layers in plasmas with two positive ion species

    International Nuclear Information System (INIS)

    Verheest, Frank; Hellberg, Manfred A.; Saini, Nareshpal Singh; Kourakis, Ioannis

    2011-01-01

    Large nonlinear acoustic waves are discussed in a plasma made up of cold supersonic and adiabatic subsonic positive ions, in the presence of hot isothermal electrons, with the help of Sagdeev pseudopotential theory. In this model, no solitons are found at the acoustic speed, and no compositional parameter ranges exist where solutions of opposite polarities can coexist. All nonlinear modes are thus super-acoustic, but polarity changes are possible. The upper limits on admissible structure velocities come from different physical arguments, in a strict order when the fractional cool ion density is increased: infinite cold ion compression, warm ion sonic point, positive double layers, negative double layers, and finally, positive double layers again. However, not all ranges exist for all mass and temperature ratios. Whereas the cold and warm ion sonic point limitations are always present over a wide range of mass and temperature ratios, and thus positive polarity solutions can easily be obtained, double layers have a more restricted existence range, specially if polarity changes are sought.

  10. Limit distributions of random walks on stochastic matrices

    Indian Academy of Sciences (India)

    condition that μm(P) > 0 for some positive integer m (as opposed to just 1, instead of m, considered in [1]), where μm is the ...... Limit distributions of random walks. 611. PROPOSITION 3.2. Let f be as introduced before Proposition 3.1. The probability distribution λ is the image of π by the map b ↦→ f (b). In other words, λ = ∑.

  11. Nonlinear acoustic waves in nonthermal plasmas with negative and positive dust

    International Nuclear Information System (INIS)

    Verheest, Frank

    2009-01-01

    Using a Sagdeev pseudopotential formalism where nonlinear structures are stationary in a co-moving frame, large dust-acoustic solitary waves and double layers have been studied in plasmas with negative and positive cold dust, in the presence of nonthermal electrons and ions. This has been done in a systematic way, to delimit the compositional parameter space in which such modes can be found. The existence domain of negative/positive solitary waves is limited by infinite compression of the negative/positive dust or by the occurrence of negative/positive double layers. These double layers require a sufficient nonthermality of the electrons/ions and the presence of enough positive/negative dust. There are parameter ranges where both negative and positive solitary structures coexist, sometimes both of the solitary wave type, sometimes one a solitary wave and the other a double layer. Typical Sagdeev pseudopotentials and solitary wave profiles have been presented.

  12. Quantum speed limits in open system dynamics

    OpenAIRE

    del Campo, A.; Egusquiza, I. L.; Plenio, M. B.; Huelga, S. F.

    2012-01-01

    Bounds to the speed of evolution of a quantum system are of fundamental interest in quantum metrology, quantum chemical dynamics and quantum computation. We derive a time-energy uncertainty relation for open quantum systems undergoing a general, completely positive and trace preserving (CPT) evolution which provides a bound to the quantum speed limit. When the evolution is of the Lindblad form, the bound is analogous to the Mandelstam-Tamm relation which applies in the unitary case, with the ...

  13. Limit on the electric charge of antihydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Capra, A., E-mail: acapra@triumf.ca; Amole, C. [York University, Department of Physics and Astronomy (Canada); Ashkezari, M. D. [Simon Fraser University, Department of Physics (Canada); Baquero-Ruiz, M. [University of California at Berkeley, Department of Physics (United States); Bertsche, W. [University of Manchester, School of Physics and Astronomy (United Kingdom); Butler, E. [Imperial College, Centre for Cold Matter (United Kingdom); Cesar, C. L. [Universidade Federal do Rio de Janeiro, Instituto de Física (Brazil); Charlton, M.; Eriksson, S. [Swansea University, Department of Physics, College of Science (United Kingdom); Fajans, J. [University of California at Berkeley, Department of Physics (United States); Friesen, T. [University of Calgary, Department of Physics and Astronomy (Canada); Fujiwara, M. C.; Gill, D. R. [TRIUMF (Canada); Gutierrez, A. [University of British Columbia, Department of Physics and Astronomy (Canada); Hangst, J. S. [CERN, Physics Department (Switzerland); Hardy, W. N. [University of British Columbia, Department of Physics and Astronomy (Canada); Hayden, M. E. [Simon Fraser University, Department of Physics (Canada); Isaac, C. A. [Swansea University, Department of Physics, College of Science (United Kingdom); Jonsell, S. [Stockholm University, Department of Physics (Sweden); Kurchaninov, L. [TRIUMF (Canada); and others

    2017-11-15

    The ALPHA collaboration has successfully demonstrated the production and the confinement of cold antihydrogen, H̅. An analysis of trapping data allowed a stringent limit to be placed on the electric charge of the simplest antiatom. Charge neutrality of matter is known to a very high precision, hence a neutrality limit of H̅ provides a test of CPT invariance. The experimental technique is based on the measurement of the deflection of putatively charged H̅ in an electric field. The tendency for trapped H̅ atoms to be displaced by electrostatic fields is measured and compared to the results of a detailed simulation of H̅ dynamics in the trap. An extensive survey of the systematic errors was performed, and this work focuses on those due to the silicon vertex detector, which is the device used to determine the H̅ annihilation position. The limit obtained on the charge of the H̅ atom is Q = (−1.3 ± 1.8 ± 0.4) × 10{sup −8}, representing the first precision measurement with H̅ [1].

  14. Scaling Limit of Symmetric Random Walk in High-Contrast Periodic Environment

    Science.gov (United States)

    Piatnitski, A.; Zhizhina, E.

    2017-11-01

    The paper deals with the asymptotic properties of a symmetric random walk in a high contrast periodic medium in Z^d, d≥1. From the existing homogenization results it follows that under diffusive scaling the limit behaviour of this random walk need not be Markovian. The goal of this work is to show that if in addition to the coordinate of the random walk in Z^d we introduce an extra variable that characterizes the position of the random walk inside the period then the limit dynamics of this two-component process is Markov. We describe the limit process and observe that the components of the limit process are coupled. We also prove the convergence in the path space for the said random walk.

  15. D walls and junctions in supersymmetric gluodynamics in the large N limit suggest the existence of heavy hadrons

    International Nuclear Information System (INIS)

    Gabadadze, Gregory; Shifman, Mikhail

    2000-01-01

    A number of arguments exists that the ''minimal'' Bogomol'nyi-Prasad-Sommerfeld (BPS) wall width in large-N supersymmetric gluodynamics vanishes as 1/N. There is a certain tension between this assertion and the fact that the mesons coupled to λλ have masses O(N 0 ). To reconcile these facts we argue that there should exist additional solitonlike states with masses scaling as N. The BPS walls must be ''made'' predominantly of these heavy states which are coupled to λλ stronger than the conventional mesons. The tension of the BPS wall junction scales as N 2 , which serves as an additional argument in favor of the 1/N scaling of the wall width. The heavy states can be thought of as solitons of the corresponding closed string theory. They are related to certain fivebranes in the M-theory construction. We study the issue of the wall width in toy models which capture some features of supersymmetric gluodynamics. We speculate that the special hadrons with mass scaling as N should also exist in the large-N limit of nonsupersymmetric gluodynamics. (c) 2000 The American Physical Society

  16. SP-100 Position Multiplexer and Analog Input Processor

    International Nuclear Information System (INIS)

    Syed, A.; Gilliland, K.; Shukla, J.N.

    1992-01-01

    This paper describes the design, implementation, and performance test results of an engineering model of the Position Multiplexer (MUX)-Analog Input Processor (AIP) System for the transmission and continuous measurements of Reflector Control Drive position in SP-100. This paper describes the work performed to determine the practical circuit limitations, investigate the circuit/component degradation of the multiplexer due to radiation, develop an interference cancellation technique, and evaluate the measurement accuracy as a function of resolver angle, temperature, radiation, and interference. The system developed performs a complex cross-correlation between the resolver excitation and the resolver sine cosine outputs, from which the precise resolver amplitude and phase can be determined while simultaneously eliminating virtually all uncorrelated interference

  17. Position-Sensitive Organic Scintillation Detectors for Nuclear Material Accountancy

    International Nuclear Information System (INIS)

    Hausladen, P.; Newby, J.; Blackston, M.

    2015-01-01

    Recent years have seen renewed interest in fast organic scintillators with pulse shape properties that enable neutron-gamma discrimination, in part because of the present shortage of He3, but primarily because of the diagnostic value of timing and pulse height information available from such scintillators. Effort at Oak Ridge National Laboratory (ORNL) associated with fast organic scintillators has concentrated on development of position-sensitive fast-neutron detectors for imaging applications. Two aspects of this effort are of interest. First, the development has revisited the fundamental limitations on pulseshape measurement imposed by photon counting statistics, properties of the scintillator, and properties of photomultiplier amplification. This idealized limit can then be used to evaluate the performance of the detector combined with data acquisition and analysis such as free-running digitizers with embedded algorithms. Second, the development of position sensitive detectors has enabled a new generation of fast-neutron imaging instruments and techniques with sufficient resolution to give new capabilities relevant to safeguards. Toward this end, ORNL has built and demonstrated a number of passive and active fast-neutron imagers, including a proof-of-concept passive imager capable of resolving individual fuel pins in an assembly via their neutron emanations. This presentation will describe the performance and construction of position-sensing fast-neutron detectors and present results of imaging measurements. (author)

  18. Parallel arrangements of positive feedback loops limit cell-to-cell variability in differentiation.

    Directory of Open Access Journals (Sweden)

    Anupam Dey

    Full Text Available Cellular differentiations are often regulated by bistable switches resulting from specific arrangements of multiple positive feedback loops (PFL fused to one another. Although bistability generates digital responses at the cellular level, stochasticity in chemical reactions causes population heterogeneity in terms of its differentiated states. We hypothesized that the specific arrangements of PFLs may have evolved to minimize the cellular heterogeneity in differentiation. In order to test this we investigated variability in cellular differentiation controlled either by parallel or serial arrangements of multiple PFLs having similar average properties under extrinsic and intrinsic noises. We find that motifs with PFLs fused in parallel to one another around a central regulator are less susceptible to noise as compared to the motifs with PFLs arranged serially. Our calculations suggest that the increased resistance to noise in parallel motifs originate from the less sensitivity of bifurcation points to the extrinsic noise. Whereas estimation of mean residence times indicate that stable branches of bifurcations are robust to intrinsic noise in parallel motifs as compared to serial motifs. Model conclusions are consistent both in AND- and OR-gate input signal configurations and also with two different modeling strategies. Our investigations provide some insight into recent findings that differentiation of preadipocyte to mature adipocyte is controlled by network of parallel PFLs.

  19. Fostering Positive Attitude in Probability Learning Using Graphing Calculator

    Science.gov (United States)

    Tan, Choo-Kim; Harji, Madhubala Bava; Lau, Siong-Hoe

    2011-01-01

    Although a plethora of research evidence highlights positive and significant outcomes of the incorporation of the Graphing Calculator (GC) in mathematics education, its use in the teaching and learning process appears to be limited. The obvious need to revisit the teaching and learning of Probability has resulted in this study, i.e. to incorporate…

  20. Positive Technologies for Understanding and Promoting Positive Emotions.

    Science.gov (United States)

    Baños, Rosa María; Carrillo, Alba; Etchemendy, Ernestina; Botella, Cristina

    2017-10-26

    Information and Communication Technologies (ICTs) have become increasingly present in our lives, and their use has spread considerably. This paper presents a review of the way ICTs can help practitioners and researchers to study, promote, and train positive emotions. It is framed within the field of Positive Technologies: the applied scientific approach to the study of the use of technology to improve the quality of personal experience, with the goal of increasing wellbeing. First, the article presents an introduction to the topic of technologies and positive emotions. Then, it describes how ICTs can aid in monitoring, assessing, promoting, modifying, and training positive emotions. Finally, implications and future directions of the role of Positive Technologies in positive emotions are discussed. The authors conclude that, in the near future, Positive Technologies and the field of positive emotions will interact synergistically, producing an exponential growth in the understanding and promotion of positive emotions.

  1. Performance of the CEBAF Arc Beam Position Monitors

    International Nuclear Information System (INIS)

    A.S. Hofler; B.A. Bowling; C.S. Higgins; P.K. Kloeppel; G.A. Krafft; K.L. Mahoney

    1993-01-01

    The first three quarters of the first CEBAF arc have been instrumented with beam position monitors. Thirty-seven monitors (of 450) have been installed and their noise measured. Resolution of 100 mu-m was obtained at the lowest operating current of 1 mu-A. The update time of the system is 1 sec, limited by computer interfacing with a potential bandwidth of greater than 10 kHz

  2. 17 CFR 200.402 - Closed meetings.

    Science.gov (United States)

    2010-04-01

    ... significant financial speculation in currencies, securities, or commodities, including, but not limited to... affecting publicly-traded securities, or (B) Significantly endanger the stability of any financial...

  3. China's climate change positions: at a turning point?

    Energy Technology Data Exchange (ETDEWEB)

    Tangen, K.; Heggelund, G.; Buen, J.

    2001-03-01

    The purpose of this article is to discuss major concerns and perceptions underlying Chinese positions in the international climate negotiations. China has asserted that concrete action on the part of developed countries is a precondition for any developing country action. It has been sceptical of the Kyoto Mechanisms and has consistently refused to discuss quantified emission limits for developing countries. China's position regarding the Clean Development Mechanism has, however, developed from scepticism towards a more pragmatic focus on maximising benefits. The dynamics of China's positioning can partly be explained by perceptions of costs, but also 'high politics', and tactical considerations. However, in light of the external and internal forces for change, it is worth asking how long it will be in China's interest to stick to its present position. (author)

  4. The equivalent internal orientation and position noise for contour integration.

    Science.gov (United States)

    Baldwin, Alex S; Fu, Minnie; Farivar, Reza; Hess, Robert F

    2017-10-12

    Contour integration is the joining-up of local responses to parts of a contour into a continuous percept. In typical studies observers detect contours formed of discrete wavelets, presented against a background of random wavelets. This measures performance for detecting contours in the limiting external noise that background provides. Our novel task measures contour integration without requiring any background noise. This allowed us to perform noise-masking experiments using orientation and position noise. From these we measure the equivalent internal noise for contour integration. We found an orientation noise of 6° and position noise of 3 arcmin. Orientation noise was 2.6x higher in contour integration compared to an orientation discrimination control task. Comparing against a position discrimination task found position noise in contours to be 2.4x lower. This suggests contour integration involves intermediate processing that enhances the quality of element position representation at the expense of element orientation. Efficiency relative to the ideal observer was lower for the contour tasks (36% in orientation noise, 21% in position noise) compared to the controls (54% and 57%).

  5. High Prevalence and Significance of Hepatitis D Virus Infection among Treatment-Naïve HBsAg-Positive Patients in Northern Vietnam

    Science.gov (United States)

    Sy, Bui Tien; Ratsch, Boris A.; Toan, Nguyen Linh; Song, Le Huu; Wollboldt, Christian; Bryniok, Agnes; Nguyen, Hung Minh; Luong, Hoang Van; Velavan, Thirumalaisamy P.; Wedemeyer, Heiner; Kremsner, Peter G.; Bock, C.-Thomas

    2013-01-01

    Background Hepatitis D virus (HDV) infection is considered to cause more severe hepatitis than hepatitis B virus (HBV) monoinfection. With more than 9.5 million HBV-infected people, Vietnam will face an enormous health burden. The prevalence of HDV in Vietnamese HBsAg-positive patients is speculative. Therefore, we assessed the prevalence of HDV in Vietnamese patients, determined the HDV-genotype distribution and compared the findings with the clinical outcome. Methods 266 sera of well-characterized HBsAg-positive patients in Northern Vietnam were analysed for the presence of HDV using newly developed HDV-specific RT-PCRs. Sequencing and phylogenetic analysis were performed for HDV-genotyping. Results The HDV-genome prevalence observed in the Vietnamese HBsAg-positive patients was high with 15.4% while patients with acute hepatitis showed 43.3%. Phylogenetic analysis demonstrated a predominance of HDV-genotype 1 clustering in an Asian clade while HDV-genotype 2 could be also detected. The serum aminotransferase levels (AST, ALT) as well as total and direct bilirubin were significantly elevated in HDV-positive individuals (p<0.05). HDV loads were mainly low (<300 to 4.108 HDV-copies/ml). Of note, higher HDV loads were mainly found in HBV-genotype mix samples in contrast to single HBV-infections. In HBV/HDV-coinfections, HBV loads were significantly higher in HBV-genotype C in comparison to HBV-genotype A samples (p<0.05). Conclusion HDV prevalence is high in Vietnamese individuals, especially in patients with acute hepatitis B. HDV replication activity showed a HBV-genotype dependency and could be associated with elevated liver parameters. Besides serological assays molecular tests are recommended for diagnosis of HDV. Finally, the high prevalence of HBV and HDV prompts the urgent need for HBV-vaccination coverage. PMID:24205106

  6. Speed and position sensors for electric motors

    Energy Technology Data Exchange (ETDEWEB)

    Lyyjynen, M. [Helsinki University of Technology, Otaniemi (Finland). Institute of Intelligent Power Electronics

    1997-12-31

    This paper gives an overview of speed and position measuring instruments for electric motors. The emphasis is on sensors that are designed to operate at industrial environment. In addition to that, some other, mostly magnetic sensors which are used, e.g., in automotive applications, are presented. Some of them are already applied in induction motors and some might be worth a try remembering the limitations. Automotive sensors are very cost-effective due to high production volumes. (orig.) 22 refs.

  7. Extensions of positive definite functions applications and their harmonic analysis

    CERN Document Server

    Jorgensen, Palle E T; Tian, Feng

    2016-01-01

    This monograph deals with the mathematics of extending given partial data-sets obtained from experiments; Experimentalists frequently gather spectral data when the observed data is limited, e.g., by the precision of instruments; or by other limiting external factors. Here the limited information is a restriction, and the extensions take the form of full positive definite function on some prescribed group. It is therefore both an art and a science to produce solid conclusions from restricted or limited data. While the theory of is important in many areas of pure and applied mathematics, it is difficult for students and for the novice to the field, to find accessible presentations which cover all relevant points of view, as well as stressing common ideas and interconnections. We have aimed at filling this gap, and we have stressed hands-on-examples.

  8. Intrinsic Subtype and Therapeutic Response Among HER2-Positive Breast Tumors from the NCCTG (Alliance) N9831 Trial

    Science.gov (United States)

    Perez, Edith A.; Ballman, Karla V.; Mashadi-Hossein, Afshin; Tenner, Kathleen S.; Kachergus, Jennifer M.; Norton, Nadine; Necela, Brian M.; Carr, Jennifer M.; Ferree, Sean; Perou, Charles M.; Baehner, Frederick; Cheang, Maggie Chon U.

    2017-01-01

    Background: Genomic data from human epidermal growth factor receptor 2–positive (HER2+) tumors were analyzed to assess the association between intrinsic subtype and clinical outcome in a large, well-annotated patient cohort. Methods: Samples from the NCCTG (Alliance) N9831 trial were analyzed using the Prosigna algorithm on the NanoString platform to define intrinsic subtype, risk of recurrence scores, and risk categories for 1392 HER2+ tumors. Subtypes were evaluated for recurrence-free survival (RFS) using Kaplan-Meier and Cox model analysis following adjuvant chemotherapy (n = 484) or chemotherapy plus trastuzumab (n = 908). All statistical tests were two-sided. Results: Patients with HER2+ tumors from N9831 were primarily scored as HER2-enriched (72.1%). These individuals received statistically significant benefit from trastuzumab (hazard ratio [HR] = 0.68, 95% confidence interval [CI] = 0.52 to 0.89, P = .005), as did the patients (291 of 1392) with luminal-type tumors (HR = 0.52, 95% CI = 0.32 to 0.85, P = .01). Patients with basal-like tumors (97 of 1392) did not have statistically significantly better RFS when treated with trastuzumab and chemotherapy compared with chemotherapy alone (HR = 1.06, 95% CI = 0.53 to 2.13, P = .87). Conclusions: The majority of clinically defined HER2-positive tumors were classified as HER2-enriched or luminal using the Prosigna algorithm. Intrinsic subtype alone cannot replace conventional histopathological evaluation of HER2 status because many tumors that are classified as luminal A or luminal B will benefit from adjuvant trastuzumab if that subtype is accompanied by HER2 overexpression. However, among tumors that overexpress HER2, we speculate that assessment of intrinsic subtype may influence treatment, particularly with respect to evaluating alternative therapeutic approaches for that subset of HER2-positive tumors of the basal-like subtype. PMID:27794124

  9. September 11th, an attack at the limits of thought.

    Science.gov (United States)

    Patalano, Roberta

    2017-10-01

    The paper deals with imagination and its failures from a psychoanalytic perspective. We offer a definition of imagination failures and suggest how they can be interpreted as an opportunity to learn from experience. In order to show that the topic has a concrete and not only speculative significance we consider the public report on September 11 as a case study. The report was published by the National Commission on Terrorist Attacks Upon the United States after a long investigation of the facts and circumstances relating to the September 11 attacks. The document has been the object of strong criticisms, as we argue in the paper. Both the document and some of the critiques that it received focus, however, on significant aspects of the debate about imagination, such us the fragility of imaginative thought, its dependence on unconscious desires and its plurality of outcomes: a plethora of imaginaries can in fact be developed at any time, from the same set of information about reality. We comment on these aspects and reinterpret them from a Bionian perspective. The concepts of 'unthinkability', 'imagination failure' and 'depressive position' are used to inform the necessity of dealing with an evolving and conflictual geopolitical scenario. Particular attention is paid to the proposal of 'routinizing, even bureaucratizing, the exercise of imagination' within the institutions that deal with National Defense. This possibility is discussed in depth in order to suggest how it may be concretely implemented. In conclusion, a strong case is made for the usefulness of psychoanalytic reflection in the arena of relationships among countries, with particular emphasis on the new terrorist challenges. Copyright © 2016 Institute of Psychoanalysis.

  10. Video-assisted thoracic surgery for superior posterior mediastinal neurogenic tumour in the supine position

    Directory of Open Access Journals (Sweden)

    Darlong Laleng

    2009-01-01

    Full Text Available Video-assisted thoracic surgery (VATS for a superior posterior mediastinal lesion is routinely done in the lateral decubitus position similar to a standard thoracotomy using a double-lumen endotracheal tube for one-lung ventilation. This is an area above the level of the pericardium, with the superior thoracic opening as its superior limit and its inferior limit at the plane from the sternal angle to the level of intervertebral disc of thoracic 4 to 5 vertebra lying behind the great vessels. The lateral decubitus position has disadvantages of the double-lumen endotracheal tube getting malpositioned during repositioning from supine position to the lateral decubitus position, shoulder injuries due to the prolonged abnormal fixed posture and rarer injuries of the lower limb. There is no literature related to VATS in the supine position for treating lesions in the posterior mediastinum because the lung tissue falls in the dependent posterior mediastinum and obscures the field of surgery; however, VATS in the supine position is routinely done for lesions in the anterior mediastinum and single-stage bilateral spontaneous pneumothorax. Thus, in the selected cases, ′VATS in supine position′ allows an invasive procedure to be completed in the most stable anatomical posture.

  11. Markers to differentiate between Kaposi's sarcoma and tuberculous pleural effusions in HIV-positive patients.

    Science.gov (United States)

    Coleman, M; Finney, L J; Komrower, D; Chitani, A; Bates, J; Chipungu, G A; Corbett, E; Allain, T J

    2015-02-01

    Kaposi's sarcoma (KS) and tuberculosis (TB) commonly cause pleural effusions in high human immunodeficiency virus (HIV) burden resource-limited countries. Differentiating between them is challenging, as pleural biopsy and TB culture are rarely available. To identify markers to differentiate between TB effusions and KS effusions in HIV-positive patients, and to compare liquid culture and Xpert MTB/RIF in pleural fluid. Fifty HIV-positive patients with pleural effusions recruited in Malawi underwent pleural ultrasound and aspiration. Fluid visual inspection, cell count, bacterial culture, glucose/protein, solid and liquid TB culture and Xpert were performed. The mean age of the patients was 32 years; 30/50 (60%) were male and 29 (58%) had cutaneous/oral KS. Thirteen (26%) pleural fluid samples were liquid culture-positive for TB, while 9/13 (69%) were Xpert-positive. Three (10.3%) KS patients had culture-positive TB effusions; 17 (58.6%) had KS effusions. The relative risk of TB in KS patients increased with limited KS, loculated fluid and low glucose. Eleven (52.3%) non-KS patients had culture-positive TB effusions associated with male sex, straw-coloured fluid and fibrin stranding on ultrasound. KS patients were most likely to have KS effusion, but TB should be considered. Most non-KS patients had TB, supporting the use of World Health Organization guidelines. Xpert identified two thirds of liquid culture-positive results.

  12. Innovative Behavior and Psychological Capital: Does Positivity Make any Difference

    Directory of Open Access Journals (Sweden)

    Yomna M. Sameer

    2018-05-01

    Full Text Available Aim/purpose - Despite increasing importance of fostering innovation among employees, and the growing interest in Positive Organizational Behaviour (POB constructs, little empirical research has been conducted on the topic of innovation with POB. Moreover, though research proved significant relationship between positive psychological capital (PsyCap and creative performance, no studies examined PsyCap with innovative behavior. Thus, the purpose of this paper is to examine the link between positive psychological capital and innovative behavior as well as the link between innovative behavior and job satisfaction as well as engagement. Design/methodology/approach - Using regression analyses, data were obtained from Egyptian professionals (N = 250. The survey included measures of psychological capital and innovative behavior as well as job satisfaction and engagement. Findings - Regression analyses reveal that PsyCap, with its four components of hope, optimism, resilience and efficacy, predict innovative behavior, which in turn affects satisfaction and engagement. Research implications/limitations - Limitations, contributions and recommendations for future research are noted. Results contribute to a better understanding of how psychological capital enhances Innovative behavior in the workplace, which in turns, enhances job satisfaction and engagement. Originality/value/contribution - The study is the first to examine the relationship between psychological capital and innovative behavior.(original abstract

  13. Limitations on continuous variable quantum algorithms with Fourier transforms

    International Nuclear Information System (INIS)

    Adcock, Mark R A; Hoeyer, Peter; Sanders, Barry C

    2009-01-01

    We study quantum algorithms implemented within a single harmonic oscillator, or equivalently within a single mode of the electromagnetic field. Logical states correspond to functions of the canonical position, and the Fourier transform to canonical momentum serves as the analogue of the Hadamard transform for this implementation. This continuous variable version of quantum information processing has widespread appeal because of advanced quantum optics technology that can create, manipulate and read Gaussian states of light. We show that, contrary to a previous claim, this implementation of quantum information processing has limitations due to a position-momentum trade-off of the Fourier transform, analogous to the famous time-bandwidth theorem of signal processing.

  14. Limits on fundamental limits to computation.

    Science.gov (United States)

    Markov, Igor L

    2014-08-14

    An indispensable part of our personal and working lives, computing has also become essential to industries and governments. Steady improvements in computer hardware have been supported by periodic doubling of transistor densities in integrated circuits over the past fifty years. Such Moore scaling now requires ever-increasing efforts, stimulating research in alternative hardware and stirring controversy. To help evaluate emerging technologies and increase our understanding of integrated-circuit scaling, here I review fundamental limits to computation in the areas of manufacturing, energy, physical space, design and verification effort, and algorithms. To outline what is achievable in principle and in practice, I recapitulate how some limits were circumvented, and compare loose and tight limits. Engineering difficulties encountered by emerging technologies may indicate yet unknown limits.

  15. Adaptation of Bacillus subtilis to Life at Extreme Potassium Limitation.

    Science.gov (United States)

    Gundlach, Jan; Herzberg, Christina; Hertel, Dietrich; Thürmer, Andrea; Daniel, Rolf; Link, Hannes; Stülke, Jörg

    2017-07-05

    Potassium is the most abundant metal ion in every living cell. This ion is essential due to its requirement for the activity of the ribosome and many enzymes but also because of its role in buffering the negative charge of nucleic acids. As the external concentrations of potassium are usually low, efficient uptake and intracellular enrichment of the ion is necessary. The Gram-positive bacterium Bacillus subtilis possesses three transporters for potassium, KtrAB, KtrCD, and the recently discovered KimA. In the absence of the high-affinity transporters KtrAB and KimA, the bacteria were unable to grow at low potassium concentrations. However, we observed the appearance of suppressor mutants that were able to overcome the potassium limitation. All these suppressor mutations affected amino acid metabolism, particularly arginine biosynthesis. In the mutants, the intracellular levels of ornithine, citrulline, and arginine were strongly increased, suggesting that these amino acids can partially substitute for potassium. This was confirmed by the observation that the supplementation with positively charged amino acids allows growth of B. subtilis even at the extreme potassium limitation that the bacteria experience if no potassium is added to the medium. In addition, a second class of suppressor mutations allowed growth at extreme potassium limitation. These mutations result in increased expression of KtrAB, the potassium transporter with the highest affinity and therefore allow the acquisition and accumulation of the smallest amounts of potassium ions from the environment. IMPORTANCE Potassium is essential for every living cell as it is required for the activity for many enzymes and for maintaining the intracellular pH by buffering the negative charge of the nucleic acids. We have studied the adaptation of the soil bacterium Bacillus subtilis to life at low potassium concentrations. If the major high-affinity transporters are missing, the bacteria are unable to grow

  16. Scaling Limit of the Noncommutative Black Hole

    International Nuclear Information System (INIS)

    Majid, Shahn

    2011-01-01

    We show that the 'quantum' black hole wave operator in the κ-Minkowski or bicrossproduct model quantum spacetime introduced in [1] has a natural scaling limit λ p → 0 at the event horizon. Here λ p is the Planck time and the geometry at the event horizon in Planck length is maintained at the same time as the limit is taken, resulting in a classical theory with quantum gravity remnants. Among the features is a frequency-dependent 'skin' of some ω/ν Planck lengths just inside the event horizon for ω > 0 and just outside for ω < 0, where v is the frequency associated to the Schwarzschild radius. We use bessel and hypergeometric functions to analyse propagation through the event horizon and skin in both directions. The analysis confirms a finite redshift at the horizon for positive frequency modes in the exterior.

  17. Are positive emotions just as "positive" across cultures?

    Science.gov (United States)

    Leu, Janxin; Wang, Jennifer; Koo, Kelly

    2011-08-01

    Whereas positive emotions and feeling unequivocally good may be at the heart of well-being among Westerners, positive emotions often carry negative associations within many Asian cultures. Based on a review of East-West cultural differences in dialectical emotions, or co-occurring positive and negative feelings, we predicted culture to influence the association between positive emotions and depression, but not the association between negative emotions and depression. As predicted, in a survey of over 600 European-, immigrant Asian-, and Asian American college students, positive emotions were associated with depression symptoms among European Americans and Asian Americans, but not immigrant Asians. Negative emotions were associated with depression symptoms among all three groups. We also found initial evidence that acculturation (i.e., nativity) may influence the role of positive emotions in depression: Asian Americans fell "in between" the two other groups. These findings suggest the importance of studying the role of culture in positive emotions and in positive psychology. The use of interventions based on promoting positive emotions in clinical psychology among Asian clients is briefly discussed. 2011 APA, all rights reserved

  18. Genetic testing of aetiology of intellectual disability in a dedicated physical healthcare outpatient clinic for adults with intellectual disability.

    Science.gov (United States)

    Wallace, R A

    2016-02-01

    No guidelines exist for assessment of aetiology of intellectual disability in adults with intellectual disability by adult physicians, although robust guidelines exist for paediatric populations. It was speculated that the paediatric guidelines would also be suitable for adults. In rural/regional setting with limited clinical genetics, to perform a quality assurance evaluation on genetics assessment of aetiology of developmental disability in adults attending a dedicated healthcare clinic for adults with intellectual disability, compared results with paediatric standards, speculates if these seem appropriate for adults and speculates on a role for clinical genetics services. Retrospective chart audit of eligible patients looking at genetic clinical assessment, tests selected (molecular karyotype, G banding, metabolics), and yields of positive results. The results were compared with the recommended paediatric guidelines. Of 117 eligible adult patients, ideal genetic history was incomplete for 40% of patients without Down syndrome because of physician cause and lack of information. The number of abnormal genetic results increased from 46% to 66%, mainly from the molecular karyotype, though not all may have been clinically relevant. The improved yield from this test was similar to that in paediatric studies. Use of G banding and metabolic testing could be refined. Improvement can be made in clinical genetic assessment, but results generally support use of molecular karyotyping as first tier testing of cause of unknown intellectual disability in adults, as in the case for paediatric populations. The study highlights a necessary complementary role for clinical geneticists to interpret abnormal results. © 2016 Royal Australasian College of Physicians.

  19. High voltage disconnect switch position monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Crampton, S W

    1983-08-01

    Unreliable position indication on high-voltage (HV) disconnect switches can result in equipment damage worth many times the cost of a disconnect switch. The benefits and limitations of a number of possible methods of reliably monitoring HV disconnect switches are assessed. Several methods of powering active devices at HV are noted. It is concluded that the most reliable way of monitoring switch position at reasonable cost would use a passive hermetically-sealed blade-position sensor located at HV, with a fibre-optic link between HV and ground. Separate sensors would be used for open and closed position indication. For maximum reliability the fibre-optic link would continue into the relay building. A passive magnetically actuated fibre-optic sensor has been built which demonstrates the feasibility of the concept. The sensor monitors blade position relative to the jaws in three dimensions with high resolution. A design for an improved passive magneto-optic sensor has significantly lower optical losses, allowing a single fibre-optic loop and 3 sensors to monitor closure of all phases of a disconnect switch. A similar loop would monitor switch opening. The improved sensor has a solid copper housing to provide greater immunity to fault currents, and to protect it from the environment and from physical damage. Two methods of providing a protected path for fibre-optics passing from HV to ground are proposed, one using a hollow porcelain switch-support insulator and the other using an additional small-diameter polymer insulator with optical fibres imbedded in its fibreglass core. A number of improvements are recommended which can be made to existing switches to increase their reliability. 16 refs., 13 figs., 1 tab.

  20. Reducing air-pollution: a new argument for getting drivers to abide by the speed limit?

    Science.gov (United States)

    Delhomme, P; Chappé, J; Grenier, K; Pinto, M; Martha, C

    2010-01-01

    Speeding is one of the main factors of car crash-risk, but it also contributes to increasing air-pollution. In two studies we attempted to lead drivers to abide by speed limits using "reducing air-pollution" as a new argument. We presented prevention messages that highlighted the role of speeding in increasing "crash-risk", "air-pollution", or both (Studies 1 and 2). The messages were also positively or negatively framed (Study 2). Given that women are more concerned with environmental issues than are men, we expected the following hypotheses to be validated for women. The message with the "air-pollution" argument was expected to be evaluated more positively than the "crash-risk" message (H1). The "air-pollution" and "crash-risk and air-pollution" messages were expected to be more effective than the "crash-risk" message on the behavioral intention to observe speed limits (H2a) and on the perceived efficacy of speed-limit observance in reducing air-pollution (H2b; Studies 1 and 2). Furthermore, positive framing was expected to be more effective than negative framing (H3), and presenting a message to be more effective than presenting no message (H4; Study 2). Broadly, our results argue in favor of our hypotheses. However in Study 2, the effects of message framing did not allow us to conclude that negative or positive framing was superior. All in all, messages with the "air-pollution" argument were more effective at leading drivers to observe speed limits. Thus, environmental protection may be a fruitful route to explore for increasing road safety.

  1. Classical particle limit of non-relativistic quantum mechanics

    International Nuclear Information System (INIS)

    Zucchini, R.

    1984-01-01

    We study the classical particle limit of non-relativistic quantum mechanics. We show that the unitary group describing the evolution of the quantum fluctuation around any classical phase orbit has a classical limit as h → 0 in the strong operator topology for a very large class of time independent scalar and vector potentials, which in practice covers all physically interesting cases. We also show that the mean values of the quantum mechanical position and velocity operators on suitable states, obtained by time evolution of the product of a Weyl operator centred around the large coordinates and momenta and a fixed n-independent wave function, converge to the solution of the classical equations with initial data as h → 0 for a broad class of repulsive interactions

  2. Partnerships – Limited partnerships and limited liability limited partnerships

    OpenAIRE

    Henning, Johan J.

    2000-01-01

    Consideration of the Limited Liability Partnership Act 2000 which introduced a new corporate entity, carrying the designations “partnership” and “limited” which allow members to limit their liability whilst organising themselves internally as a partnership. Article by Professor Johan Henning (Director of the Centre for Corporate Law and Practice, IALS and Dean of the Faculty of Law, University of the Free State, South Africa). Published in Amicus Curiae - Journal of the Institute of Advanced ...

  3. Detecting positive quadrant dependence and positive function dependence

    NARCIS (Netherlands)

    Janic-Wróblewska, A.; Kallenberg, W.C.M.; Ledwina, T.

    2004-01-01

    There is a lot of interest in positive dependence going beyond linear correlation. In this paper three new rank tests for testing independence against positive dependence are introduced. The first one is directed on positive quadrant dependence, the second and third one concentrate on positive

  4. Detecting positive quadrant dependence and positive function dependence

    NARCIS (Netherlands)

    Janic-Wróblewska, A.; Kallenberg, W.C.M.; Ledwina, T.

    2003-01-01

    There is a lot of interest in positive dependence going beyond linear correlation. In this paper three new rank tests for testing independence against positive dependence are introduced. The first one is directed on positive quadrant dependence, the second and third one concentrate on positive

  5. The limitation and modification of flux-limited diffusion theory

    International Nuclear Information System (INIS)

    Liu Chengan; Huang Wenkai

    1986-01-01

    The limitation of various typical flux-limited diffusion theory and advantages of asymptotic diffusion theory with time absorption constant are analyzed and compared. The conclusions are as following: Though the flux-limited problem in neutron diffusion theory are theoretically solved by derived flux-limited diffusion equation, it's going too far to limit flux due to the inappropriate assumption in deriving flux-limited diffusion equation. The asymptotic diffusion theory with time absorption constant has eliminated the above-mentioned limitation, and it is more accurate than flux-limited diffusion theory in describing neutron transport problem

  6. Exploring the relation between positive emotions and the functional status of older adults living independently: a systematic review.

    Science.gov (United States)

    Cabrita, Miriam; Lamers, Sanne M A; Trompetter, Hester R; Tabak, Monique; Vollenbroek-Hutten, Miriam M R

    2017-11-01

    Literature suggests that positive emotions positively influence physiological parameters but their relation to functioning in the daily life of older adults living independently remains unclear. The present work aims to investigate the relation between positive emotions and functional status in daily life of older people living independently. A systematic literature review was conducted using the PubMed, PsycINFO and Scopus electronic databases. Included works were peer-reviewed empirical studies that analysed the relation between positive emotions and ability to perform activities of daily living with older adults living independently. After removal of duplicates, 10 out of 963 papers met the inclusion criteria. Cross-sectional studies (n = 6) provided limited evidence about a relation between positive emotions and functioning in daily life. However, longitudinal studies (n = 4) provide significant evidence for an interaction between the two factors, suggesting that time influences this interaction. The variety on the design and samples of the studies included in this review does not allow a cohesive conclusion of the results. Nevertheless, limited evidence suggests that higher frequency in the experience of positive emotions might be associated with lower functional limitations. The issue of causality in emotions-functioning remains unclear from the review. Further observational studies are highly recommended, supported by innovative technologies.

  7. Different views about work-hour limitations in medicine: a qualitative content analysis of surgeons', lawyers', and pilots' positive and negative arguments.

    Directory of Open Access Journals (Sweden)

    Adrian P Businger

    Full Text Available Whereas work-hour regulations have been taken for granted since 1940 in other occupational settings, such as commercial aviation, they have been implemented only recently in medical professions, where they lead to a lively debate. The aim of the present study was to evaluate arguments in favour of and against work-hour limitations in medicine given by Swiss surgeons, lawyers, and pilots.An electronic questionnaire survey with four free-response items addressing the question of what arguments speak in favour of or against work-hour limitations in general and in medicine was sent to a random sample of board-certified surgeons, lawyers in labour law, and pilots from SWISS International Airlines Ltd.In all, 279/497 (56% of the respondents answered the survey: 67/117 surgeons, 92/226 lawyers, and 120/154 pilots. Support for work-hour limitations in general and in medicine was present and higher among lawyers and pilots than it was in surgeons (p<0.001. The latter agreed more with work-hour limitations in general than in medicine (p<0.001. The most often cited arguments in favour of work-hour limitations were "quality and patient safety," "health and fitness," and "leisure and work-family balance," whereas the lack of "flexibility" was the most important argument against. Surgeons expected more often that their "education" and the "quality of their work" would be threatened (p<0.001.Work-hour limitations should be supported in medicine also, but a way must be found to reduce problems resulting from discontinuity in patient care and to minimise the work in medicine, which has no education value.

  8. Influence of the vibro-acoustic sensor position on cavitation detection in a Kaplan turbine

    Science.gov (United States)

    Schmidt, H.; Kirschner, O.; Riedelbauch, S.; Necker, J.; Kopf, E.; Rieg, M.; Arantes, G.; Wessiak, M.; Mayrhuber, J.

    2014-03-01

    Hydraulic turbines can be operated close to the limits of the operating range to meet the demand of the grid. When operated close to the limits, the risk increases that cavitation phenomena may occur at the runner and / or at the guide vanes of the turbine. Cavitation in a hydraulic turbine can cause material erosion on the runner and other turbine parts and reduce the durability of the machine leading to required outage time and related repair costs. Therefore it is important to get reliable information about the appearance of cavitation during prototype operation. In this experimental investigation the high frequency acoustic emissions and vibrations were measured at 20 operating points with different cavitation behaviour at different positions in a large prototype Kaplan turbine. The main goal was a comparison of the measured signals at different sensor positions to identify the sensitivity of the location for cavitation detection. The measured signals were analysed statistically and specific values were derived. Based on the measured signals, it is possible to confirm the cavitation limit of the examined turbine. The result of the investigation shows that the position of the sensors has a significant influence on the detection of cavitation.

  9. Influence of the vibro-acoustic sensor position on cavitation detection in a Kaplan turbine

    International Nuclear Information System (INIS)

    Schmidt, H; Kirschner, O; Riedelbauch, S; Necker, J; Kopf, E; Rieg, M; Arantes, G; Wessiak, M; Mayrhuber, J

    2014-01-01

    Hydraulic turbines can be operated close to the limits of the operating range to meet the demand of the grid. When operated close to the limits, the risk increases that cavitation phenomena may occur at the runner and / or at the guide vanes of the turbine. Cavitation in a hydraulic turbine can cause material erosion on the runner and other turbine parts and reduce the durability of the machine leading to required outage time and related repair costs. Therefore it is important to get reliable information about the appearance of cavitation during prototype operation. In this experimental investigation the high frequency acoustic emissions and vibrations were measured at 20 operating points with different cavitation behaviour at different positions in a large prototype Kaplan turbine. The main goal was a comparison of the measured signals at different sensor positions to identify the sensitivity of the location for cavitation detection. The measured signals were analysed statistically and specific values were derived. Based on the measured signals, it is possible to confirm the cavitation limit of the examined turbine. The result of the investigation shows that the position of the sensors has a significant influence on the detection of cavitation

  10. Control system design for nano-positioning using piezoelectric actuators

    International Nuclear Information System (INIS)

    Shan, Jinjun; Liu, Yanfang; Cui, Naigang; Gabbert, Ulrich

    2016-01-01

    This paper presents a systematic control system design for nano-positioning of a piezoelectric actuator (PEA). PEAs exhibit hysteresis nonlinearity, which can dramatically limit the application and performance of linear feedback control theory. Thus the hysteresis is compensated for based on the Maxwell resistive capacitor (MRC) model first. Then a proportional plus integral (PI) controller and a proportional double integral plus lead compensation (PII and L) controller are designed for the hysteresis-compensated PEA to account for model uncertainty, disturbance, and noise. The robust stability of both controllers is proved. The effectiveness of the proposed control scheme is demonstrated experimentally. Both controllers achieve fast precise positioning. The 2% settling times for the PI controller and the PII and L controller are 1.5 ms and 4.7 ms, respectively. The positioning resolution is upto 1 nm for both controllers. (paper)

  11. Head and neck position sense.

    Science.gov (United States)

    Armstrong, Bridget; McNair, Peter; Taylor, Denise

    2008-01-01

    fails to be appropriately integrated in the CNS, errors in head position may occur, resulting in an inaccurate reference for HNPS, and conversely if neck proprioceptive information is inaccurate, then control of head position may be affected. The cerebellum and cortex also play a role in control of head position, providing feed-forward and modulatory influences depending on the task requirements. Position-matching tasks have been the most popular means of testing position sense in the cervical spine. These allow the appreciation of absolute, constant and variable errors in positioning and have been shown to be reliable. The results of such tests indicate that errors are relatively low (2-5 degrees). It is apparent that error is not consistently affected by age, a finding similar to studies undertaken in peripheral joints. Furthermore, the range of motion in which subjects are tested does not consistently affect accuracy in a predictable manner. However, it is evident that impairments in position sense are observed in individuals who have experienced whiplash-type injuries and individuals with chronic head and neck pain of non-traumatic origin (e.g. cervical spondylosis). While researchers advocate comprehensive retraining protocols, which include eye and neck motion targeting tasks and coordination exercises, as well as co-contraction exercises to reduce such impairments, some studies show that more general exercises and manipulation may be of benefit. Overall, there is limited information concerning the efficacy of treatment programmes.

  12. Investigations of radial electric field and global circulation layer in limiter tokamaks

    International Nuclear Information System (INIS)

    Zagorski, R.; Gerhauser, H.; Lehnen, M.; Loarer, T.

    2002-01-01

    An updated version of the 2D multifluid code TECXY is used to study the radial electric field structure and the appearance of a global circulation layer (GCL) inside the separatrix of the limiter tokamaks TEXTOR-94 and Tore-Supra-CIEL. The dependence of the driving forces on device geometry, limiter position, magnetic field orientation, impurity content and other parameters is investigated. The centrifugal force in the vicinity of the limiter head always determines the direction of the poloidal velocity in the GCL. There is good agreement with experimentally measured profiles of the poloidal velocity at the TEXTOR low field side. (orig.)

  13. A fast high-precision six-degree-of-freedom relative position sensor

    Science.gov (United States)

    Hughes, Gary B.; Macasaet, Van P.; Griswold, Janelle; Sison, Claudia A.; Lubin, Philip; Meinhold, Peter; Suen, Jonathan; Brashears, Travis; Zhang, Qicheng; Madajian, Jonathan

    2016-03-01

    Lasers are commonly used in high-precision measurement and profiling systems. Some laser measurement systems are based on interferometry principles, and others are based on active triangulation, depending on requirements of the application. This paper describes an active triangulation laser measurement system for a specific application wherein the relative position of two fixed, rigid mechanical components is to be measured dynamically with high precision in six degrees of freedom (DOF). Potential applications include optical systems with feedback to control for mechanical vibration, such as target acquisition devices with multiple focal planes. The method uses an array of several laser emitters mounted on one component. The lasers are directed at a reflective surface on the second component. The reflective surface consists of a piecewise-planar pattern such as a pyramid, or more generally a curved reflective surface such as a hyperbolic paraboloid. The reflected spots are sensed at 2-dimensional photodiode arrays on the emitter component. Changes in the relative position of the emitter component and reflective surface will shift the location of the reflected spots within photodiode arrays. Relative motion in any degree of freedom produces independent shifts in the reflected spot locations, allowing full six-DOF relative position determination between the two component positions. Response time of the sensor is limited by the read-out rate of the photodiode arrays. Algorithms are given for position determination with limits on uncertainty and sensitivity, based on laser and spot-sensor characteristics, and assuming regular surfaces. Additional uncertainty analysis is achievable for surface irregularities based on calibration data.

  14. Entanglement and the process of measuring the position of a quantum particle

    International Nuclear Information System (INIS)

    Apel, V.M.; Curilef, S.; Plastino, A.R.

    2015-01-01

    We explore the entanglement-related features exhibited by the dynamics of a composite quantum system consisting of a particle and an apparatus (here referred to as the “pointer”) that measures the position of the particle. We consider measurements of finite duration, and also the limit case of instantaneous measurements. We investigate the time evolution of the quantum entanglement between the particle and the pointer, with special emphasis on the final entanglement associated with the limit case of an impulsive interaction. We consider entanglement indicators based on the expectation values of an appropriate family of observables, and also an entanglement measure computed on particular exact analytical solutions of the particle–pointer Schrödinger equation. The general behavior exhibited by the entanglement indicators is consistent with that shown by the entanglement measure evaluated on particular analytical solutions of the Schrödinger equation. In the limit of instantaneous measurements the system’s entanglement dynamics corresponds to that of an ideal quantum measurement process. On the contrary, we show that the entanglement evolution corresponding to measurements of finite duration departs in important ways from the behavior associated with ideal measurements. In particular, highly localized initial states of the particle lead to highly entangled final states of the particle–pointer system. This indicates that the above mentioned initial states, in spite of having an arbitrarily small position uncertainty, are not left unchanged by a finite-duration position measurement process. - Highlights: • We explore entanglement features of a quantum position measurement. • We consider instantaneous and finite-duration measurements. • We evaluate the entanglement of exact time-dependent particle–pointer states

  15. 2 DOF resolution adjustment laser position sensor

    CSIR Research Space (South Africa)

    Shaik, A

    2008-12-01

    Full Text Available means. [19, 20] Other - Displacement measuring instruments utilizing eddy currents, capacitive and inductive properties exist, but are not as widely spread as the technologies mentioned. Accelerometers and Gyroscopes are used to determine... resolution. The current accuracy of the IRB 340 Flex Picker, a rapid pick and place machine, is 0.1 mm. The lower limit on screen resolution for absolute 2D positioning would then be 400 phototransistors per square mm, a screen with twice the resolution...

  16. MDEP Common Position CP-DICWG-13. Common position on spurious actuation

    International Nuclear Information System (INIS)

    2017-01-01

    Spurious actuations produced by Instrumentation and Control (I and C) systems are a safety concern if such actuations could challenge plant safety. Spurious actuations can lead to unnecessary challenges to safety equipment, challenge the ability of safety systems to provide their intended functions, or place the plant in an un-analysed state. Spurious actuation of plant equipment can be caused by factors including, but not limited to, single failures, common cause failures, human (e.g. operator) action, maintenance errors, design errors, or missing requirements. Modern I and C systems can have inter-connectivities, dependencies and commonalities that can, if the overall I and C architecture and the individual I and C systems are not adequately developed and operated, facilitate fault propagation, leading to potential spurious actuation of one or more trains of plant equipment. Sources and contributors of spurious actuations of multiple trains of plant equipment may include inadequate independence among redundant portions of I and C systems, inappropriate allocation of I and C functions, inadequate qualification or design of supporting systems (e.g. heating, ventilation and air conditioning (HVAC) system), or non-classified systems that could have been erroneously classified. Spurious actuations are a type of hazard. Generic Common Position (GCP) DICWG-10 'Common Position on Hazard Identification and Controls for Digital Instrumentation and Control Systems' provides a set of common positions pertaining to identifying and controlling hazards in an I and C system. This common position was developed to add special considerations when identifying and controlling hazards that include spurious actuations. It is expected that GCP DICWG-10 and the common positions in this document be used together for a complete analysis of hazards and their controls (e.g. prevention of spurious actuations in the design of the system/component). Spurious actuations of concern

  17. The Coo Effect in the International Brand Positioning Strategy

    Directory of Open Access Journals (Sweden)

    Barbara Kobuszewski Volles

    2016-12-01

    Full Text Available Abstract Purpose: This study aims to develop a model in order to understand how Chinese companies strategically position their brands, considering the causes of the country of origin (COO effect, when going through the process of internationalization. Design/methodology/approach: The study approach a qualitative case study that incorporates two different Chinese companies with subsidiaries settled in Brazil. It was conducted depth interviews with different components of the studied firms. Findings: In this way, it was developed a model that try to explain the positive and/or negative effect of general attributes from China (labor market, institution framework and education on the brand positioning divers (value preposition, points of leverage, primary target and image reinforcement, which influences on the cost-benefit strategy approach of the brands when positioning internationally. Research limitations/implications: Considering that this research is a qualitative study of two Chinese companies, further qualitative and quantitative studies would be fruitful to the validity of the presented model. Originality/value: In order to contribute to the academic field, it was found that this research present a unique model considering different causes of the COO effect that might affect the international branding positioning.

  18. Les limites du capitalisme selon Joseph Schumpeter et Karl Marx The limits of capitalism by Joseph Schumpeter and Karl Marx

    Directory of Open Access Journals (Sweden)

    Omer Moussaly

    2012-11-01

    Full Text Available À jongler avec les mérites et les ratés de la théorie de Marx et de ses adeptes, Schumpeter semble vouloir s’imposer en tant qu’arbitre unique et impartial du marxisme. Bien qu’il reconnaisse plusieurs mérites à la conception économique de Marx, Schumpeter soulève de multiples limites à l’analyse des marxistes orthodoxes qui ne font que corroborer sa prise de position critique du marxisme. Une lecture des critiques et des réponses que Schumpeter a adressées au marxisme permet de révéler les points communs et les divergences entre les deux auteurs. Chez Schumpeter comme chez Marx, le capitalisme est un mode passager de la production sociale. Schumpeter se fixe comme objectif de combler la lacune des marxistes qui n’ont pas su identifier les vraies raisons du dépérissement du capitalisme. Il lui fallait relever le défi de critiquer certains adeptes de Marx sans pour autant s’en prendre trop au fondateur du marxisme auquel il vouait une admiration sincère.Juggling with the merits and flaws of Marx and his followers, Schumpeter seems to be acting as an impartial judge, especially since he eliminates the extreme arguments of both the Marxists and their opponents. His technique seeks to make his position unassailable from either side of the debate. Although he recognizes several merits to the economic conceptions of Marx, Schumpeter points out several limits of orthodox Marxists which only confirm his critical position towards Marxism. A careful reading of Schumpeter’s commentary on Marxism reveals many points in common between himself and Marx. For Schumpeter as for Marx, capitalism is a transitory and historically limited social mode of production. Unlike most Marxists, who merely repeated ideological slogans from the works of Marx, Schumpeter believed he had discovered the true reasons behind capitalism’s demise. With his critique of Marxism, Schumpeter did not wish to diminish the merit of its founder, but rather

  19. The adult spinal cord harbors a population of GFAP-positive progenitors with limited self-renewal potential.

    Science.gov (United States)

    Fiorelli, Roberto; Cebrian-Silla, Arantxa; Garcia-Verdugo, Jose-Manuel; Raineteau, Olivier

    2013-12-01

    Adult neural stem cells (aNSCs) of the forebrain are GFAP-expressing cells that are intercalated within ependymal cells of the subventricular zone (SVZ). Cells showing NSCs characteristics in vitro can also be isolated from the periaqueductal region in the adult spinal cord (SC), but contradicting results exist concerning their glial versus ependymal identity. We used an inducible transgenic mouse line (hGFAP-CreERT2) to conditionally label GFAP-expressing cells in the adult SVZ and SC periaqueduct, and directly and systematically compared their self-renewal and multipotential properties in vitro. We demonstrate that a population of GFAP(+) cells that share the morphology and the antigenic properties of SVZ-NSCs mostly reside in the dorsal aspect of the central canal (CC) throughout the spinal cord. These cells are non-proliferative in the intact spinal cord, but incorporate the S-phase marker EdU following spinal cord injury. Multipotent, clonal YFP-expressing neurospheres (i.e., deriving from recombined GFAP-expressing cells) were successfully obtained from both the intact and injured spinal cord. These spheres however showed limited self-renewal properties when compared with SVZ-neurospheres, even after spinal cord injury. Altogether, these results demonstrate that significant differences exist in NSCs lineages between neurogenic and non-neurogenic regions of the adult CNS. Thus, although we confirm that a population of multipotent GFAP(+) cells co-exists alongside with multipotent ependymal cells within the adult SC, we identify these cells as multipotent progenitors showing limited self-renewal properties. Copyright © 2013 Wiley Periodicals, Inc.

  20. Current limiters

    Energy Technology Data Exchange (ETDEWEB)

    Loescher, D.H. [Sandia National Labs., Albuquerque, NM (United States). Systems Surety Assessment Dept.; Noren, K. [Univ. of Idaho, Moscow, ID (United States). Dept. of Electrical Engineering

    1996-09-01

    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  1. Speculative dynamic vectorization to assist static vectorization in a HW/SW co-designed environment

    OpenAIRE

    Kumar, R.; Martinez, A.; Gonzalez, A.

    2013-01-01

    Compiler based static vectorization is used widely to extract data level parallelism from computation intensive applications. Static vectorization is very effective in vectorizing traditional array based applications. However, compilers inability to reorder ambiguous memory references severely limits vectorization opportunities, especially in pointer rich applications. HW/SW co-designed processors provide an excellent opportunity to optimize the applications at runtime. The availability of dy...

  2. Ideal MHD B limits in the BIG DEE tokamak

    International Nuclear Information System (INIS)

    Helton, F.J.; Bernard, L.C.; Greene, J.M.

    1983-01-01

    Using D-D reactions, tokamak reactors become economically attractive when B (the ratio of volume averaged pressure to magnetic pressure) exceeds 5 percent. Ideal MID instabilities are of great concern because they have the potential to limit B below this range and so extensive studies have been done to determine ideal MHD B limits. As B increases with inverse aspect ratio, elongation and triangularity, the Doublet III upgrade machine -- BIG DEE -- is particularly suited to study the possibility of very high B. The authors have done computations to determine ideal MHD B limits for various plasma shapes and elongations in BIG DEE. They have determined that for q at the plasma surface greater than 2, B is limited by the ballooning mode if the wall is reasonably close to the plasma surface (d/a < 1.5 where d and a are the wall and plasma radii respectively). On the other hand, for q at the plasma surface less than 2, the n=1 external kink is unstable even with a wall close by. Thus, relevant values of limiting B can be obtained by assuming that the external kink limits the value of q at the limiter to a value greater than 2 and that the ballooning modes limit B. Under this assumption, a relevant B limit for the BIG DEE would be over 18%. For such an equilibrium, the wall position necessary to stabilize the n=1 and n=2 modes is 2a and the equilibrium is stable for n=3

  3. Beam-limiting and radiation-limiting interlocks

    International Nuclear Information System (INIS)

    Macek, R.J.

    1996-01-01

    This paper reviews several aspects of beam-limiting and radiation- limiting interlocks used for personnel protection at high-intensity accelerators. It is based heavily on the experience at the Los Alamos Neutron Science Center (LANSCE) where instrumentation-based protection is used extensively. Topics include the need for ''active'' protection systems, system requirements, design criteria, and means of achieving and assessing acceptable reliability. The experience with several specific devices (ion chamber-based beam loss interlock, beam current limiter interlock, and neutron radiation interlock) designed and/or deployed to these requirements and criteria is evaluated

  4. Relationship of condylar position to disc position and morphology

    Energy Technology Data Exchange (ETDEWEB)

    Incesu, L.; Taskaya-Yilmaz, N. E-mail: nergizy@omu.edu.tr; Oeguetcen-Toller, M.; Uzun, E

    2004-09-01

    Introduction/objective: The purpose of this study was to assess whether condylar position, as depicted by magnetic resonance imaging, was an indicator of disc morphology and position. Methods and material: One hundred and twenty two TMJs of 61 patients with temporomandibular joint disorder were examined. Condylar position, disc deformity and degree of anterior disc displacement were evaluated by using magnetic resonance imaging. Results and discussion: Posterior condyle position was found to be the main feature of temporomandibular joints with slight and moderate anterior disc displacement. No statistical significance was found between the condylar position, and reducing and nonreducing disc positions. On the other hand, superior disc position was found to be statistically significant for centric condylar position. Conclusion: It was concluded that posterior condyle position could indicate anterior disc displacement whereas there was no relation between the position of condyle and the disc deformity.

  5. Fusion Based on Visible Light Positioning and Inertial Navigation Using Extended Kalman Filters.

    Science.gov (United States)

    Li, Zhitian; Feng, Lihui; Yang, Aiying

    2017-05-11

    With the rapid development of smart technology, the need for location-based services (LBS) increases every day. Since classical positioning technology such as GPS cannot satisfy the needs of indoor positioning, new indoor positioning technologies, such as Bluetooth, Wi-Fi, and Visible light communication (VLC), have already cut a figure. VLC positioning has been proposed because it has higher accuracy, costs less, and is easier to accomplish in comparison to the other indoor positioning technologies. However, the practicality of VLC positioning is limited since it is easily affected by multipath effects and the layout of LEDs. Thus, we propose a fusion positioning system based on extended Kalman filters, which can fuse the VLC position and the inertial navigation data. The accuracy of the fusion positioning system is in centimeters, which is better compared to the VLC-based positioning or inertial navigation alone. Furthermore, the fusion positioning system has high accuracy, saves energy, costs little, and is easy to install, making it a promising candidate for future indoor positioning applications.

  6. Material limitations on the detection limit in refractometry.

    Science.gov (United States)

    Skafte-Pedersen, Peder; Nunes, Pedro S; Xiao, Sanshui; Mortensen, Niels Asger

    2009-01-01

    We discuss the detection limit for refractometric sensors relying on high-Q optical cavities and show that the ultimate classical detection limit is given by min {Δn} ≳ η, with n + iη being the complex refractive index of the material under refractometric investigation. Taking finite Q factors and filling fractions into account, the detection limit declines. As an example we discuss the fundamental limits of silicon-based high-Q resonators, such as photonic crystal resonators, for sensing in a bio-liquid environment, such as a water buffer. In the transparency window (λ ≳ 1100 nm) of silicon the detection limit becomes almost independent on the filling fraction, while in the visible, the detection limit depends strongly on the filling fraction because the silicon absorbs strongly.

  7. Speculation, Hedging, and Interest Rates

    DEFF Research Database (Denmark)

    Buraschi, Andrea; Whelan, Paul

    of Treasury bond markets that the singleagent paradigm finds difficult to reconcile. Empirically, we test predictions from themodel using a large dataset on beliefs about fundamentals and find that: (i) shocksto disagreement lower short term interest rates; (ii) raise the slope of the yield curve;and (iii...

  8. Speculative values and courtroom contestations

    NARCIS (Netherlands)

    de Goede, M.

    2015-01-01

    This article examines the trial of former Goldman Sachs employee Fabrice Tourre, who was held liable for securities fraud in 2013, and asks what it tells us about postcrisis understanding of politics and critique. What does it mean to hold Tourre individually liable amid the complex

  9. Speculative attacks, openness and crises

    Directory of Open Access Journals (Sweden)

    Aloisio Araujo

    2012-06-01

    Full Text Available We extended the Cole and Kehoe model (1996 by adding trade and debt denominated in national currency. We then evaluated some external debt defaults and steep national currency devaluations occurred during last decades. Although default is unlikely, steep devaluation has been repeatedly triggered during financial distresses. It helps to overcome financial crisis as it improves trade balance and reduces national debt level. On the other hand, expected devaluation hurts welfare through both higher national debt cost and reductions in the investment level. We modeled such trade-offs and showed that trade openness, by and large, improves the expected welfare as it allows for a better devaluation-response technology. We ran model simulations based on past 48 crises occurred in 32 middle-income countries, reasonably fitting devaluation and default responses observed as from 1971.

  10. Monetary policy during speculative attacks

    DEFF Research Database (Denmark)

    Bergman, Ulf Michael; Jellingsø, Mads

    2010-01-01

    This paper extends the currency crises model of Aghion, Bacchetta and Banerjee (2000, 2001, 2004) in different directions. Our main result is that a tight monetary policy can have adverse effects beyond the short term and can potentially cause a currency crisis in the medium term, even in cases w...

  11. Style in Malawian speculative fiction

    African Journals Online (AJOL)

    Lipenga

    effect, and to account for what it is that we are responding to when we praise ..... the narrative) is an unborn child she refers to as “babi” (Nhlema, 2015b). The ... characters; J.K Rowling in Harry Potter (1997) in generating a new wizarding.

  12. Real-time positioning technology in horizontal directional drilling based on magnetic gradient tensor measurement

    Science.gov (United States)

    Deng, Guoqing; Yao, Aiguo

    2017-04-01

    Horizontal directional drilling (HDD) technology has been widely used in Civil Engineering. The dynamic position of the drill bit during construction is one of significant facts determining the accuracy of the trajectory of HDD. A new method now has been proposed to detecting the position of drill bit by measuring the magnetic gradient tensor of the ground solenoid magnetic beacon. Compared with traditional HDD positioning technologies, this new model is much easier to apply with lower request for construction sites and higher positioning efficiency. A direct current (DC) solenoid as a magnetic dipole is placed on ground near the drill bit, and related sensors array which contains four Micro-electromechanical Systems (MEMS ) tri-axial magnetometers, one MEMS tri-axial accelerometer and one MEMS tri-axial gyroscope is set up for measuring the magnetic gradient tensor of the magnetic dipole. The related HDD positioning model has been established and simulation experiments have been carried out to verify the feasibility and reliability of the proposed method. The experiments show that this method has good positioning accuracy in horizontal and vertical direction, and totally avoid the impact of the environmental magnetic field. It can be found that the posture of the magnetic beacon will impact the remote positioning precision within valid positioning range, and the positioning accuracy is higher with longer baseline for limited space in drilling tools. The results prove that the relative error can be limited in 2% by adjusting position of the magnetic beacon, the layers of the enameled coil, the sensitive of magnetometers and the baseline distance. Conclusion can be made that this new method can be applied in HDD positioning with better effect and wider application range than traditional method.

  13. A signal strength priority based position estimation for mobile platforms

    Science.gov (United States)

    Kalgikar, Bhargav; Akopian, David; Chen, Philip

    2010-01-01

    Global Positioning System (GPS) products help to navigate while driving, hiking, boating, and flying. GPS uses a combination of orbiting satellites to determine position coordinates. This works great in most outdoor areas, but the satellite signals are not strong enough to penetrate inside most indoor environments. As a result, a new strain of indoor positioning technologies that make use of 802.11 wireless LANs (WLAN) is beginning to appear on the market. In WLAN positioning the system either monitors propagation delays between wireless access points and wireless device users to apply trilateration techniques or it maintains the database of location-specific signal fingerprints which is used to identify the most likely match of incoming signal data with those preliminary surveyed and saved in the database. In this paper we investigate the issue of deploying WLAN positioning software on mobile platforms with typically limited computational resources. We suggest a novel received signal strength rank order based location estimation system to reduce computational loads with a robust performance. The proposed system performance is compared to conventional approaches.

  14. Indoor anti-occlusion visible light positioning systems based on particle filtering

    Science.gov (United States)

    Jiang, Meng; Huang, Zhitong; Li, Jianfeng; Zhang, Ruqi; Ji, Yuefeng

    2015-04-01

    As one of the most popular categories of mobile services, a rapid growth of indoor location-based services has been witnessed over the past decades. Indoor positioning methods based on Wi-Fi, radio-frequency identification or Bluetooth are widely commercialized; however, they have disadvantages such as low accuracy or high cost. An emerging method using visible light is under research recently. The existed visible light positioning (VLP) schemes using carrier allocation, time allocation and multiple receivers all have limitations. This paper presents a novel mechanism using particle filtering in VLP system. By this method no additional devices are needed and the occlusion problem in visible light would be alleviated which will effectively enhance the flexibility for indoor positioning.

  15. Positive mood broadens visual attention to positive stimuli.

    Science.gov (United States)

    Wadlinger, Heather A; Isaacowitz, Derek M

    2006-03-01

    In an attempt to investigate the impact of positive emotions on visual attention within the context of Fredrickson's (1998) broaden-and-build model, eye tracking was used in two studies to measure visual attentional preferences of college students (n=58, n=26) to emotional pictures. Half of each sample experienced induced positive mood immediately before viewing slides of three similarly-valenced images, in varying central-peripheral arrays. Attentional breadth was determined by measuring the percentage viewing time to peripheral images as well as by the number of visual saccades participants made per slide. Consistent with Fredrickson's theory, the first study showed that individuals induced into positive mood fixated more on peripheral stimuli than did control participants; however, this only held true for highly-valenced positive stimuli. Participants under induced positive mood also made more frequent saccades for slides of neutral and positive valence. A second study showed that these effects were not simply due to differences in emotional arousal between stimuli. Selective attentional broadening to positive stimuli may act both to facilitate later building of resources as well as to maintain current positive affective states.

  16. Material Limitations on the Detection Limit in Refractometry

    Directory of Open Access Journals (Sweden)

    Niels Asger Mortensen

    2009-10-01

    Full Text Available We discuss the detection limit for refractometric sensors relying on high-Q optical cavities and show that the ultimate classical detection limit is given by min {Δn} ≳ η with n + iη being the complex refractive index of the material under refractometric investigation. Taking finite Q factors and filling fractions into account, the detection limit declines. As an example we discuss the fundamental limits of silicon-based high-Q resonators, such as photonic crystal resonators, for sensing in a bio-liquid environment, such as a water buffer. In the transparency window (λ ≳ 1100 nm of silicon the detection limit becomes almost independent on the filling fraction, while in the visible, the detection limit depends strongly on the filling fraction because the silicon absorbs strongly.

  17. Positive airway pressure adherence and subthreshold adherence in posttraumatic stress disorder patients with comorbid sleep apnea

    Directory of Open Access Journals (Sweden)

    Krakow BJ

    2017-11-01

    Full Text Available Barry J Krakow,1–3 Jessica J Obando,2 Victor A Ulibarri,1,2 Natalia D McIver1,2 1Sleep & Human Health Institute, 2Maimonides Sleep Arts & Sciences, Albuquerque, 3Los Alamos Medical Center, Los Alamos, NM, USA Study objectives: Patients with comorbid posttraumatic stress disorder (PTSD and obstructive sleep apnea (OSA manifest low adherence to continuous positive airway pressure (CPAP due to fixed, pressure-induced expiratory pressure intolerance (EPI, a subjective symptom and objective sign aggravated by anxiety sensitivity and somatosensory amplification. As advanced PAP therapy modes (ie, auto-bilevel PAP [ABPAP] or adaptive servo-ventilation [ASV] may address these side effects, we hypothesized such treatment would be associated with decreased expiratory intolerance and increased adherence in posttraumatic stress patients with co-occurring OSA.Methods: We reviewed charts of 147 consecutive adult patients with moderately severe posttraumatic stress symptoms and objectively diagnosed OSA. All patients failed or rejected CPAP and were manually titrated on auto-adjusting, dual-pressure ABPAP or ASV modes in the sleep laboratory, a technique to eliminate flow limitation breathing events while resolving EPI. Patients were then prescribed either mode of therapy. Follow-up encounters assessed patient use, and objective data downloads (ODDs measured adherence.Results: Of 147 charts reviewed, 130 patients were deemed current PAP users, and 102 provided ODDs: 64 used ASV and 38 used ABPAP. ODDs yielded three groups: 59 adherent per insurance conventions, 19 subthreshold compliant partial users, and 24 noncompliant. Compliance based on available downloads was 58%, notably higher than recently reported rates in PTSD patients with OSA. Among the 19 partial users, 17 patients were minutes of PAP use or small percentages of nights removed from meeting insurance compliance criteria for PAP devices.Conclusion: Research is warranted on advanced PAP modes in

  18. A novel particle filter approach for indoor positioning by fusing WiFi and inertial sensors

    Directory of Open Access Journals (Sweden)

    Zhu Nan

    2015-12-01

    Full Text Available WiFi fingerprinting is the method of recording WiFi signal strength from access points (AP along with the positions at which they were recorded, and later matching those to new measurements for indoor positioning. Inertial positioning utilizes the accelerometer and gyroscopes for pedestrian positioning. However, both methods have their limitations, such as the WiFi fluctuations and the accumulative error of inertial sensors. Usually, the filtering method is used for integrating the two approaches to achieve better location accuracy. In the real environments, especially in the indoor field, the APs could be sparse and short range. To overcome the limitations, a novel particle filter approach based on Rao Blackwellized particle filter (RBPF is presented in this paper. The indoor environment is divided into several local maps, which are assumed to be independent of each other. The local areas are estimated by the local particle filter, whereas the global areas are combined by the global particle filter. The algorithm has been investigated by real field trials using a WiFi tablet on hand with an inertial sensor on foot. It could be concluded that the proposed method reduces the complexity of the positioning algorithm obviously, as well as offers a significant improvement in position accuracy compared to other conventional algorithms, allowing indoor positioning error below 1.2 m.

  19. Comparison of pulsar positions from timing and very long baseline astrometry

    Science.gov (United States)

    Wang, J. B.; Coles, W. A.; Hobbs, G.; Shannon, R. M.; Manchester, R. N.; Kerr, M.; Yuan, J. P.; Wang, N.; Bailes, M.; Bhat, N. D. R.; Dai, S.; Dempsey, J.; Keith, M. J.; Lasky, P. D.; Levin, Y.; Osłowski, S.; Ravi, V.; Reardon, D. J.; Rosado, P. A.; Russell, C. J.; Spiewak, R.; van Straten, W.; Toomey, L.; Wen, L.; You, X.-P.; Zhu, X.-J.

    2017-07-01

    Pulsar positions can be measured with high precision using both pulsar timing methods and very long baseline interferometry (VLBI). Pulsar timing positions are referenced to a solar-system ephemeris, whereas VLBI positions are referenced to distant quasars. Here, we compare pulsar positions from published VLBI measurements with those obtained from pulsar timing data from the Nanshan and Parkes radio telescopes in order to relate the two reference frames. We find that the timing positions differ significantly from the VLBI positions (and also differ between different ephemerides). A statistically significant change in the obliquity of the ecliptic of 2.16 ± 0.33 mas is found for the JPL ephemeris DE405, but no significant rotation is found in subsequent JPL ephemerides. The accuracy with which we can relate the two frames is limited by the current uncertainties in the VLBI reference source positions and in matching the pulsars to their reference source. Not only do the timing positions depend on the ephemeris used in computing them, but also different segments of the timing data lead to varying position estimates. These variations are mostly common to all ephemerides, but slight changes are seen at the 10 μas level between ephemerides.

  20. Position displacement effect on the doses in the peripheral head regions

    International Nuclear Information System (INIS)

    Kortesniemi, M.; Seppaelae, T.; Bjugg, H.; Seren, T.; Kotiluoto, P.; Auterinen, I.; Parkkinen, R.; Savolainen, S.

    2000-01-01

    Patient positioning is a challenging task in BNCT-treatments due to the use of multiple fields and a static horizontal beam construction. Positioning accuracy of 5 mm is required for acceptable dose delivery within appropriate limits of dose uncertainty (up to 10% of point dose in target volume). The aim of this study was to determine if a patient head position creating a clear gap between the beam port and the head would have a significant effect on the doses to the peripheral regions of the head, e.g. to the eyes. The gamma dose rates were measured in a water filled ellipsoidal phantom with an ionisation chamber (IC). Mn activation wires were used to determine the Mn-55(n, γ) reaction rates. Twelve measurement points were chosen in the phantom and two phantom positions were applied. According to this study the 35 mm position change and the resulting gap has an obvious effect on the peripheral doses in BNCT. The Mn activation reaction rates were on the average 80% higher in the deviation position than in the reference position. Increasing depth from the surface inside the phantom diminished the gamma dose difference between the two positions. Scattering environment changes with position displacement and resulting gap causes differences in neutron fluences and gamma doses. (author)

  1. Embedded wavelet-based face recognition under variable position

    Science.gov (United States)

    Cotret, Pascal; Chevobbe, Stéphane; Darouich, Mehdi

    2015-02-01

    For several years, face recognition has been a hot topic in the image processing field: this technique is applied in several domains such as CCTV, electronic devices delocking and so on. In this context, this work studies the efficiency of a wavelet-based face recognition method in terms of subject position robustness and performance on various systems. The use of wavelet transform has a limited impact on the position robustness of PCA-based face recognition. This work shows, for a well-known database (Yale face database B*), that subject position in a 3D space can vary up to 10% of the original ROI size without decreasing recognition rates. Face recognition is performed on approximation coefficients of the image wavelet transform: results are still satisfying after 3 levels of decomposition. Furthermore, face database size can be divided by a factor 64 (22K with K = 3). In the context of ultra-embedded vision systems, memory footprint is one of the key points to be addressed; that is the reason why compression techniques such as wavelet transform are interesting. Furthermore, it leads to a low-complexity face detection stage compliant with limited computation resources available on such systems. The approach described in this work is tested on three platforms from a standard x86-based computer towards nanocomputers such as RaspberryPi and SECO boards. For K = 3 and a database with 40 faces, the execution mean time for one frame is 0.64 ms on a x86-based computer, 9 ms on a SECO board and 26 ms on a RaspberryPi (B model).

  2. Advantages and limitations of peer assessment

    Directory of Open Access Journals (Sweden)

    Karmen Goršak, Karmen Pižorn

    2010-12-01

    Full Text Available This article examines current theoretical work and research findings regarding the effectiveness of peer assessment. The main purpose of the article is to define peer asses sment and its subcategory peer feedback and to present the advantages and limitations of peer assessment derived from different research findings. In addition, conditions and strategies to successfully guarantee the benefits of peer assessment are presented. The main research studies, mentioned in this article, have been carried out in different disciplines in higher education programmes and their findings reveal positive students’ and teachers’ attitude to peer assessment as well as high correlation between peers’ and te achers’ grades. The main results of the studies show a positive effect of peer assessment on student’s active role in the process of learning and assessment, the development of social and professional skills, student’s autonomy, critical thinking, peer and selfassessment skills. Recommendations for implementing peer assessment within foreign language tea ching, as well as implications for future research work are provided.

  3. Applications and limitations of quantitative sacroiliac joint scintigraphy

    International Nuclear Information System (INIS)

    Goldberg, R.P.; Genant, H.K.; Shimshak, R.; Shames, D.

    1978-01-01

    Evaluation of sacroiliac joint pathology by quantitative analysis of radionuclide bone scanning has been advocated as a useful technique. We have examined this technique in 61 patients and controls. The procedure was useful in detecting early sacroilitis but was of limited value in patients with advanced sacroiliac joint findings radiographically. False positive values were found in patients with metabolic bone disease or structural abnormalities in the low back. Normative data must be determined for each laboratory

  4. The position profiles of order cancellations in an emerging stock market

    International Nuclear Information System (INIS)

    Gu, Gao-Feng; Ren, Fei; Zhou, Wei-Xing; Xiong, Xiong; Zhang, Wei

    2013-01-01

    Order submission and cancellation are two constituent actions of stock trading behaviors in order-driven markets. Order submission dynamics has been extensively studied for different markets, while order cancellation dynamics is less understood. There are two positions associated with a cancellation, that is, the price level in the limit-order book (LOB) and the position in the queue at each price level. We study the profiles of these two order cancellation positions through rebuilding the limit-order book using the order flow data of 23 liquid stocks traded on the Shenzhen Stock Exchange in the year 2003. We find that the profiles of relative price levels where cancellations occur obey a log-normal distribution. After normalizing the relative price level by removing the factor of order numbers stored at the price level, we find that the profiles exhibit a power-law scaling behavior on the right tails for both buy and sell orders. When focusing on the order cancellation positions in the queue at each price level, we find that the profiles increase rapidly in the front of the queue, and then fluctuate around a constant value till the end of the queue. These profiles are similar for different stocks. In addition, the profiles of cancellation positions can be fitted by an exponent function for both buy and sell orders. These two kinds of cancellation profiles seem universal for different stocks investigated and exhibit minor asymmetry between buy and sell orders. Our empirical findings shed new light on the order cancellation dynamics and pose constraints on the construction of order-driven stock market models. (paper)

  5. A Randomized Comparison of In-hospital Rescuer Positions for Endotracheal Intubation in a Difficult Airway

    OpenAIRE

    Le Parc, Joanna M.; Bischof, Jason J.; King, Andrew M.; Greenberger, Sarah; Way, David P.; Panchal, Ashish R.; Finnegan, Geoffrey I.; Terndrup, Thomas E.

    2018-01-01

    Introduction: Emergency endotracheal intubation (ETI) is a common and critical procedure performed in both prehospital and in-hospital settings. Studies of prehospital providers have demonstrated that rescuer position influences ETI outcomes. However, studies of in-hospital rescuer position for ETI are limited. While we adhere to strict standards for the administration of ETI, we posited that perhaps requiring in-hospital rescuers to stand for ETI is an obstacle to effectiveness. Our objectiv...

  6. Long-term psychosocial consequences of false-positive screening mammography

    DEFF Research Database (Denmark)

    Brodersen, John; Siersma, Volkert Dirk

    2013-01-01

    Cancer screening programs have the potential of intended beneficial effects, but they also inevitably have unintended harmful effects. In the case of screening mammography, the most frequent harm is a false-positive result. Prior efforts to measure their psychosocial consequences have been limite...... by short-term follow-up, the use of generic survey instruments, and the lack of a relevant benchmark-women with breast cancer....

  7. Curved spaces before Einstein: Karl Schwarzschild's cosmological speculations and the beginnings of relativistic cosmology (German Title: Gekrümmte Universen vor Einstein: Karl Schwarzschilds kosmologische Spekulationen und die Anfänge der relativistischen Kosmologie)

    Science.gov (United States)

    Schemmel, Matthias

    In contrast to most of his collegues in astronomy and physics, the German astronomer Karl Schwarzschild immediately recognized the significance of general relativity for physics and astronomy, and played a pioneering role in its early development. In this contribution, it is argued that the clue for understanding Schwarzschild's exceptional reaction to general relativity lies in the study of his prerelativistic work. Long before the rise of general relativity, Schwarzschild occupied himself with foundational problems on the borderline of physics, astronomy, and mathematics that, from today's perspective, belong to the field of problems of that theory. In this contribution, the example of Schwarzschild's early speculations about the non-Euclidean nature of physical space on cosmological scales is presented and their reflection in his reception of general relativity is discussed.

  8. Positioning consumption

    DEFF Research Database (Denmark)

    Halkier, Bente; Keller, Margit

    2014-01-01

    positionings emerges based on empirical examples of research in parent–children consumption. Positionings are flexible discursive fixations of the relationship between the performances of the practitioner, other practitioners, media discourse and consumption activities. The basic positioning types...... are the practice maintenance and the practice change position, with different sorts of adapting in between. Media discourse can become a resource for a resistant position against social control or for an appropriating position in favour of space for action. Regardless of the current relation to a particular media......This article analyses the ways in which media discourses become a part of contested consumption activities. We apply a positioning perspective with practice theory to focus on how practitioners relate to media discourse as a symbolic resource in their everyday practices. A typology of performance...

  9. The investigation in radiation protection of γ-rays material position meter in Guizhou Province

    International Nuclear Information System (INIS)

    Wei Fuxing

    1997-01-01

    The paper investigates the protective property of 38 γ-rays material position meters used in machine vertical kilns by 36 cement factories in Guizhou. Model FLW-II material position meter use the least radioactive source activity and the air absorption dose rate about one meter is equal to the natural background. For model FWJ-77A, the air absorption dose rate around one meter was 1.1-5.3 μGY/h and the average value is 2.1 +- 0.7 μGY/h; for Model LF-I, they are respectively 0.42-6.4 μGY/h and 2.4 +- 0.6 μGY/h. These value are lower than or near to the dose limit value which state stipulated. The biggest dose equivalent that maintenance workers accepted per year is only equal to 1/2∼1/3 of the dose limit value which state stipulated. Some management suggestions for the production, sellment and use of γ-rays material position meter were presented

  10. Vehicle Maximum Weight Limitation Based on Intelligent Weight Sensor

    Science.gov (United States)

    Raihan, W.; Tessar, R. M.; Ernest, C. O. S.; E Byan, W. R.; Winda, A.

    2017-03-01

    Vehicle weight is an important factor to be maintained for transportation safety. A weight limitation system is proposed to make sure the vehicle weight is always below its designation prior the vehicle is being used by the driver. The proposed system is divided into two systems, namely vehicle weight confirmation system and weight warning system. In vehicle weight confirmation system, the weight sensor work for the first time after the ignition switch is turned on. When the weight is under the weight limit, the starter engine can be switched on to start the engine system, otherwise it will be locked. The seconds system, will operated after checking all the door at close position, once the door of the car is closed, the weight warning system will check once again the weight during runing engine condition. The results of these two systems, vehicle weight confirmation system and weight warning system have 100 % accuracy, respectively. These show that the proposed vehicle weight limitation system operate well.

  11. Provisional Thoughts on Limitations to the Right to Procreate

    Directory of Open Access Journals (Sweden)

    JA (Robbie Robinson

    2015-07-01

    Full Text Available The constantly increasing human population results in severe ecological, psychological, political, economic and sociological ramifications. These negative implications raise the question whether the constitutionally entrenched right to make decisions concerning reproduction may be limited, as the continued existence of the State may ultimately be jeopardised if the population is not kept "[d]own to the means of subsistence". An analysis of relevant constitutional provisions shows that in essence it is the "inner sanctum" of the individual which is shielded from erosion by conflicting rights of the community, and that the outward manifestation of the right (procreation may indeed be limited. However, the so-called Chinese experience shows that negative measures have the desired results but also had a severe non-intended impact on the social and economic situation in China. It is suggested, therefore, that positive measures (eg proper education and social provision be considered to limit population growth.

  12. Approach motivation and cognitive resources combine to influence memory for positive emotional stimuli.

    Science.gov (United States)

    Crowell, Adrienne; Schmeichel, Brandon J

    2016-01-01

    Inspired by the elaborated intrusion theory of desire, the current research tested the hypothesis that persons higher in trait approach motivation process positive stimuli deeply, which enhances memory for them. Ninety-four undergraduates completed a measure of trait approach motivation, viewed positive or negative image slideshows in the presence or absence of a cognitive load, and one week later completed an image memory test. Higher trait approach motivation predicted better memory for the positive slideshow, but this memory boost disappeared under cognitive load. Approach motivation did not influence memory for the negative slideshow. The current findings support the idea that individuals higher in approach motivation spontaneously devote limited resources to processing positive stimuli.

  13. Material Limitations on the Detection Limit in Refractometry

    OpenAIRE

    Skafte-Pedersen, Peder; Nunes, Pedro S.; Xiao, Sanshui; Mortensen, Niels Asger

    2009-01-01

    We discuss the detection limit for refractometric sensors relying on high-Q optical cavities and show that the ultimate classical detection limit is given by min {Δn} ≳ η with n + iη being the complex refractive index of the material under refractometric investigation. Taking finite Q factors and filling fractions into account, the detection limit declines. As an example we discuss the fundamental limits of silicon-based high-Q resonators, such as photonic crystal resonators, for sensing in a...

  14. Living With Limited Time: Socioemotional Selectivity Theory in the Context of Health Adversity

    OpenAIRE

    Sullivan-Singh, Sarah J.; Stanton, Annette L.; Low, Carissa A.

    2015-01-01

    The current research was designed to test the applicability of socioemotional selectivity theory (SST; Carstensen, 2006), a life span theory that posits that perceived time remaining in life (time perspective) is a critical determinant of motivation, to individuals who face foreshortened futures (limited time perspective) due to life-limiting medical illness. In Study 1, we investigated whether life goals and biases in attention and memory for valenced emotional stimuli differed between women...

  15. False Position, Double False Position and Cramer's Rule

    Science.gov (United States)

    Boman, Eugene

    2009-01-01

    We state and prove the methods of False Position (Regula Falsa) and Double False Position (Regula Duorum Falsorum). The history of both is traced from ancient Egypt and China through the work of Fibonacci, ending with a connection between Double False Position and Cramer's Rule.

  16. Survey on Ranging Sensors and Cooperative Techniques for Relative Positioning of Vehicles

    Directory of Open Access Journals (Sweden)

    Fabian de Ponte Müller

    2017-01-01

    Full Text Available Future driver assistance systems will rely on accurate, reliable and continuous knowledge on the position of other road participants, including pedestrians, bicycles and other vehicles. The usual approach to tackle this requirement is to use on-board ranging sensors inside the vehicle. Radar, laser scanners or vision-based systems are able to detect objects in their line-of-sight. In contrast to these non-cooperative ranging sensors, cooperative approaches follow a strategy in which other road participants actively support the estimation of the relative position. The limitations of on-board ranging sensors regarding their detection range and angle of view and the facility of blockage can be approached by using a cooperative approach based on vehicle-to-vehicle communication. The fusion of both, cooperative and non-cooperative strategies, seems to offer the largest benefits regarding accuracy, availability and robustness. This survey offers the reader a comprehensive review on different techniques for vehicle relative positioning. The reader will learn the important performance indicators when it comes to relative positioning of vehicles, the different technologies that are both commercially available and currently under research, their expected performance and their intrinsic limitations. Moreover, the latest research in the area of vision-based systems for vehicle detection, as well as the latest work on GNSS-based vehicle localization and vehicular communication for relative positioning of vehicles, are reviewed. The survey also includes the research work on the fusion of cooperative and non-cooperative approaches to increase the reliability and the availability.

  17. Power transport to the PDX scoop limiter

    International Nuclear Information System (INIS)

    Kugel, H.W.; Bol, K.; Budny, R.

    1986-07-01

    Power transport to the PDX graphite scoop limiter was measured during both ohmic- and neutral-beam-heated discharges by observing its front face temperatures using an infrared camera. Measurements were made as a function of plasma density, current, position, fueling mode, and heating power for both co- and counter-neutral beam injection. The measured thermal load on the scoop limiter was 25 to 50% of the total plasma heating power. The measured peak front face midplane temperature was 1500 0 C corresponding to a peak surface power density of 3 kW/cm 2 . This power density implies an effective parallel power flow of 54 kW/cm 2 in agreement with the radial power distribution extrapolated from TVTS and calorimetry measurements. Symmetric and asymmetric thermal loads were observed. The asymmetric heat loads were predominantly skewed toward the respective ion drift directions for both co- and counter-injected beams. The results of transport calculations are consistent with the direction and magnitude of the observed asymmetries

  18. The Role of Positive Emotions in Positive Psychology: The Broaden-and-Build Theory of Positive Emotions.

    Science.gov (United States)

    Fredrickson, Barbara L.

    2001-01-01

    Describes the broaden-and-build theory of positive emotions, situating it within the field of positive psychology. The theory posits that experiences of positive emotions broaden people's momentary thought-action repertoires, which in turn build their enduring personal resources (physical, intellectual, social, and psychological). Reviews…

  19. Ubiquitous positioning

    CERN Document Server

    Mannings, Robin

    2008-01-01

    This groundbreaking resource offers a practical, in-depth understanding of Ubiquitous Positioning - positioning systems that identify the location and position of people, vehicles and objects in time and space in the digitized networked economy. The future and growth of ubiquitous positioning will be fueled by the convergence of many other areas of technology, from mobile telematics, Internet technology, and location systems, to sensing systems, geographic information systems, and the semantic web. This first-of-its-kind volume explores ubiquitous positioning from a convergence perspective, of

  20. A Sleep Position Trainer for positional sleep apnea

    DEFF Research Database (Denmark)

    Laub, Rasmus R; Tønnesen, Philip; Jennum, Poul J

    2017-01-01

    We tested the effect of the Sleep Position Trainer, a vibrational device, for positional sleep apnea in an open, randomized controlled trial with 101 patients, where 52 patients were allocated to Sleep Position Trainer and 49 patients to a non-treatment control group for 2 months (Part 1). All...... patients were then followed as a cohort for a period of 6 months with use of the Sleep Position Trainer (Part 2). The participants were assessed with polygraphy at entry, and after 2 and 6 months. The mean apnea-hypopnea index supine was 35 per h (SD, 18) in the Sleep Position Trainer group and 38 per h...... (SD, 15) in the control group at entry. In a per protocol analysis, the mean total apnea-hypopnea index at entry and after 2 months in the Sleep Position Trainer group was 18 per h (SD, 10) and 10 per h (SD, 9; P