WorldWideScience

Sample records for surprisingly large effect

  1. Equilibrium deuterium isotope effect of surprising magnitude

    International Nuclear Information System (INIS)

    Goldstein, M.J.; Pressman, E.J.

    1981-01-01

    Seemingly large deuterium isotope effects are reported for the preference of deuterium for the α-chloro site to the bridgehead or to the vinyl site in samples of anti-7-chlorobicyclo[4.3.2]undecatetraene-d 1 . Studies of molecular models did not provide a basis for these large equilibrium deuterium isotope effects. The possibility is proposed that these isotope effects only appear to be large for want of comparison with isotope effects measured for molecules that might provide even greater contrasts in local force fields

  2. Effects of surprisal and locality on Danish sentence processing

    DEFF Research Database (Denmark)

    Balling, Laura Winther; Kizach, Johannes

    2017-01-01

    An eye-tracking experiment in Danish investigates two dominant accounts of sentence processing: locality-based theories that predict a processing advantage for sentences where the distance between the major syntactic heads is minimized, and the surprisal theory which predicts that processing time...

  3. Carbon Dioxide: Surprising Effects on Decision Making and Neurocognitive Performance

    Science.gov (United States)

    James, John T.

    2013-01-01

    The occupants of modern submarines and the International Space Station (ISS) have much in common as far as their air quality is concerned. Air is polluted by materials offgassing, use of utility compounds, leaks of systems chemicals, and anthropogenic sources. The primary anthropogenic compound of concern to submariners and astronauts has been carbon dioxide (CO2). NASA and the US Navy rely on the National Research Council Committee on Toxicology (NRC-COT) to help formulate exposure levels to CO2 that are thought to be safe for exposures of 3-6 months. NASA calls its limits Spacecraft Maximum Allowable Concentrations (SMACs). Years of experience aboard the ISS and a recent publication on deficits in decision making in ground-based subjects exposed briefly to 0.25% CO2 suggest that exposure levels that have been presumed acceptable to preserve health and performance need to be reevaluated. The current CO2 exposure limits for 3-6 months set by NASA and the UK Navy are 0.7%, and the limit for US submariners is 0.5%, although the NRC-COT recommended a 90-day level of 0.8% as safe a few years ago. NASA has set a 1000-day SMAC at 0.5% for exploration-class missions. Anecdotal experience with ISS operations approaching the current 180-day SMAC of 0.7% suggest that this limit is too high. Temporarily, NASA has limited exposures to 0.5% until further peer-reviewed data become available. In the meantime, a study published last year in the journal Environmental Health Perspectives (Satish U, et al. 2012) demonstrated that complexdecision- making performance is somewhat affected at 0.1% CO2 and becomes "dysfunctional" for at least half of the 9 indices of performance at concentrations approaching 0.25% CO2. The investigators used the Strategic Management Simulation (SMS) method of testing for decisionmaking ability, and the results were so surprising to the investigators that they declared that their findings need to be independently confirmed. NASA has responded to the

  4. Surprise, Recipes for Surprise, and Social Influence.

    Science.gov (United States)

    Loewenstein, Jeffrey

    2018-02-07

    Surprising people can provide an opening for influencing them. Surprises garner attention, are arousing, are memorable, and can prompt shifts in understanding. Less noted is that, as a result, surprises can serve to persuade others by leading them to shifts in attitudes. Furthermore, because stories, pictures, and music can generate surprises and those can be widely shared, surprise can have broad social influence. People also tend to share surprising items with others, as anyone on social media has discovered. This means that in addition to broadcasting surprising information, surprising items can also spread through networks. The joint result is that surprise not only has individual effects on beliefs and attitudes but also collective effects on the content of culture. Items that generate surprise need not be random or accidental. There are predictable methods or recipes for generating surprise. One such recipe is discussed, the repetition-break plot structure, to explore the psychological and social possibilities of examining surprise. Recipes for surprise offer a useful means for understanding how surprise works and offer prospects for harnessing surprise to a wide array of ends. Copyright © 2017 Cognitive Science Society, Inc.

  5. Surprise, Memory, and Retrospective Judgment Making: Testing Cognitive Reconstruction Theories of the Hindsight Bias Effect

    Science.gov (United States)

    Ash, Ivan K.

    2009-01-01

    Hindsight bias has been shown to be a pervasive and potentially harmful decision-making bias. A review of 4 competing cognitive reconstruction theories of hindsight bias revealed conflicting predictions about the role and effect of expectation or surprise in retrospective judgment formation. Two experiments tested these predictions examining the…

  6. Ontological Surprises

    DEFF Research Database (Denmark)

    Leahu, Lucian

    2016-01-01

    a hybrid approach where machine learning algorithms are used to identify objects as well as connections between them; finally, it argues for remaining open to ontological surprises in machine learning as they may enable the crafting of different relations with and through technologies.......This paper investigates how we might rethink design as the technological crafting of human-machine relations in the context of a machine learning technique called neural networks. It analyzes Google’s Inceptionism project, which uses neural networks for image recognition. The surprising output...

  7. Surprise Trips

    DEFF Research Database (Denmark)

    Korn, Matthias; Kawash, Raghid; Andersen, Lisbet Møller

    2010-01-01

    We report on a platform that augments the natural experience of exploration in diverse indoor and outdoor environments. The system builds on the theme of surprises in terms of user expectations and finding points of interest. It utilizes physical icons as representations of users' interests...... and as notification tokens to alert users when they are within proximity of a surprise. To evaluate the concept, we developed mock-ups, a video prototype and conducted a wizard-of-oz user test for a national park in Denmark....

  8. The effect of emotionally valenced eye region images on visuocortical processing of surprised faces.

    Science.gov (United States)

    Li, Shuaixia; Li, Ping; Wang, Wei; Zhu, Xiangru; Luo, Wenbo

    2018-05-01

    In this study, we presented pictorial representations of happy, neutral, and fearful expressions projected in the eye regions to determine whether the eye region alone is sufficient to produce a context effect. Participants were asked to judge the valence of surprised faces that had been preceded by a picture of an eye region. Behavioral results showed that affective ratings of surprised faces were context dependent. Prime-related ERPs with presentation of happy eyes elicited a larger P1 than those for neutral and fearful eyes, likely due to the recognition advantage provided by a happy expression. Target-related ERPs showed that surprised faces in the context of fearful and happy eyes elicited dramatically larger C1 than those in the neutral context, which reflected the modulation by predictions during the earliest stages of face processing. There were larger N170 with neutral and fearful eye contexts compared to the happy context, suggesting faces were being integrated with contextual threat information. The P3 component exhibited enhanced brain activity in response to faces preceded by happy and fearful eyes compared with neutral eyes, indicating motivated attention processing may be involved at this stage. Altogether, these results indicate for the first time that the influence of isolated eye regions on the perception of surprised faces involves preferential processing at the early stages and elaborate processing at the late stages. Moreover, higher cognitive processes such as predictions and attention can modulate face processing from the earliest stages in a top-down manner. © 2017 Society for Psychophysiological Research.

  9. Charming surprise

    CERN Multimedia

    Antonella Del Rosso

    2011-01-01

    The CP violation in charm quarks has always been thought to be extremely small. So, looking at particle decays involving matter and antimatter, the LHCb experiment has recently been surprised to observe that things might be different. Theorists are on the case. The study of the physics of the charm quark was not in the initial plans of the LHCb experiment, whose letter “b” stands for “beauty quark”. However, already one year ago, the Collaboration decided to look into a wider spectrum of processes that involve charm quarks among other things. The LHCb trigger allows a lot of these processes to be selected, and, among them, one has recently shown interesting features. Other experiments at b-factories have already performed the same measurement but this is the first time that it has been possible to achieve such high precision, thanks to the huge amount of data provided by the very high luminosity of the LHC. “We have observed the decay modes of the D0, a pa...

  10. Charming surprise

    CERN Multimedia

    Antonella Del Rosso

    2011-01-01

    The CP violation in charm quarks has always been thought to be extremely small. So, looking at particle decays involving matter and antimatter, the LHCb experiment has recently been surprised to observe that things might be different. Theorists are on the case.   The study of the physics of the charm quark was not in the initial plans of the LHCb experiment, whose letter “b” stands for “beauty quark”. However, already one year ago, the Collaboration decided to look into a wider spectrum of processes that involve charm quarks among other things. The LHCb trigger allows a lot of these processes to be selected, and, among them, one has recently shown interesting features. Other experiments at b-factories have already performed the same measurement but this is the first time that it has been possible to achieve such high precision, thanks to the huge amount of data provided by the very high luminosity of the LHC. “We have observed the decay modes of t...

  11. Effect of Temperature Shock and Inventory Surprises on Natural Gas and Heating Oil Futures Returns

    Science.gov (United States)

    Hu, John Wei-Shan; Lin, Chien-Yu

    2014-01-01

    The aim of this paper is to examine the impact of temperature shock on both near-month and far-month natural gas and heating oil futures returns by extending the weather and storage models of the previous study. Several notable findings from the empirical studies are presented. First, the expected temperature shock significantly and positively affects both the near-month and far-month natural gas and heating oil futures returns. Next, significant temperature shock has effect on both the conditional mean and volatility of natural gas and heating oil prices. The results indicate that expected inventory surprises significantly and negatively affects the far-month natural gas futures returns. Moreover, volatility of natural gas futures returns is higher on Thursdays and that of near-month heating oil futures returns is higher on Wednesdays than other days. Finally, it is found that storage announcement for natural gas significantly affects near-month and far-month natural gas futures returns. Furthermore, both natural gas and heating oil futures returns are affected more by the weighted average temperature reported by multiple weather reporting stations than that reported by a single weather reporting station. PMID:25133233

  12. Corn Ethanol: The Surprisingly Effective Route for Natural Gas Consumption in the Transportation Sector

    Energy Technology Data Exchange (ETDEWEB)

    Szybist, James P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Curran, Scott [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-05-01

    Proven reserves and production of natural gas (NG) in the United States have increased dramatically in the last decade, due largely to the commercialization of hydraulic fracturing. This has led to a plentiful supply of NG, resulting in a significantly lower cost on a gallon of gasoline-equivalent (GGE) basis. Additionally, NG is a domestic, non-petroleum source of energy that is less carbon-intensive than coal or petroleum products, and thus can lead to lower greenhouse gas emissions. Because of these factors, there is a desire to increase the use of NG in the transportation sector in the United States (U.S.). However, using NG directly in the transportation sector requires that several non-trivial challenges be overcome. One of these issues is the fueling infrastructure. There are currently only 1,375 NG fueling stations in the U.S. compared to 152,995 fueling stations for gasoline in 2014. Additionally, there are very few light-duty vehicles that can consume this fuel directly as dedicated or bi-fuel options. For example, in model year 2013Honda was the only OEM to offer a dedicated CNG sedan while a number of others offered CNG options as a preparation package for LD trucks and vans. In total, there were a total of 11 vehicle models in 2013 that could be purchased that could use natural gas directly. There are additional potential issues associated with NG vehicles as well. Compared to commercial refueling stations, the at-home refueling time for NG vehicles is substantial – a result of the small compressors used for home refilling. Additionally, the methane emissions from both refueling (leakage) and from tailpipe emissions (slip) from these vehicles can add to their GHG footprint, and while these emissions are not currently regulated it could be a barrier in the future, especially in scenarios with broad scale adoption of CNG vehicles. However, NG consumption already plays a large role in other sectors of the economy, including some that are important to

  13. Surprisingly low frequency attenuation effects in long tubes when measuring turbulent fluxes at tall towers

    DEFF Research Database (Denmark)

    Ibrom, Andreas; Brændholt, Andreas; Pilegaard, Kim

    2016-01-01

    The eddy covariance technique relies on the fast and accurate measurement of gas concentration fluctuations. While for some gasses robust and compact sensors are available, measurement of, e.g., non CO2 greenhouse gas fluxes is often performed with sensitive equipment that cannot be run on a tower...... without massively disturbing the wind field. To measure CO and N2O fluxes, we installed an eddy covariance system at a 125 m mast, where the gas analyser was kept in a laboratory close to the tower and the sampling was performed using a 150 m long tube with a gas intake at 96 m height. We investigated...... by reducing both the water vapour dilution correction and the cross sensitivity effects on the N2O and CO flux measurements. Here we present the set-up of the concentration step change experiment and its results and compare them with recently developed theories for the behaviour of gases in turbulent tube...

  14. Feedback first: the surprisingly weak effects of magnetic fields, viscosity, conduction and metal diffusion on sub-L* galaxy formation

    Science.gov (United States)

    Su, Kung-Yi; Hopkins, Philip F.; Hayward, Christopher C.; Faucher-Giguère, Claude-André; Kereš, Dušan; Ma, Xiangcheng; Robles, Victor H.

    2017-10-01

    Using high-resolution simulations with explicit treatment of stellar feedback physics based on the FIRE (Feedback In Realistic Environments) project, we study how galaxy formation and the interstellar medium (ISM) are affected by magnetic fields, anisotropic Spitzer-Braginskii conduction and viscosity, and sub-grid metal diffusion from unresolved turbulence. We consider controlled simulations of isolated (non-cosmological) galaxies but also a limited set of cosmological 'zoom-in' simulations. Although simulations have shown significant effects from these physics with weak or absent stellar feedback, the effects are much weaker than those of stellar feedback when the latter is modelled explicitly. The additional physics have no systematic effect on galactic star formation rates (SFRs). In contrast, removing stellar feedback leads to SFRs being overpredicted by factors of ˜10-100. Without feedback, neither galactic winds nor volume-filling hot-phase gas exist, and discs tend to runaway collapse to ultra-thin scaleheights with unphysically dense clumps congregating at the galactic centre. With stellar feedback, a multi-phase, turbulent medium with galactic fountains and winds is established. At currently achievable resolutions and for the investigated halo mass range 1010-1013 M⊙, the additional physics investigated here (magnetohydrodynamic, conduction, viscosity, metal diffusion) have only weak (˜10 per cent-level) effects on regulating SFR and altering the balance of phases, outflows or the energy in ISM turbulence, consistent with simple equipartition arguments. We conclude that galactic star formation and the ISM are primarily governed by a combination of turbulence, gravitational instabilities and feedback. We add the caveat that active galactic nucleus feedback is not included in the present work.

  15. The effects of black-tailed prairie dogs on plant communities within a complex urban landscape: an ecological surprise?

    Science.gov (United States)

    Beals, Stower C; Hartley, Laurel M; Prevéy, Janet S; Seastedt, Timothy R

    2014-05-01

    Historically, prairie dogs (Cynomys spp.) have been considered essential keystone species of western United States grassland ecosystems because they provide unique services and increase vegetation community richness, evenness, and diversity. However, the effects of black-tailed prairie dogs (Cynomys ludovicianus) on lands adjacent to or surrounded by urban areas may not result in the same ecosystem benefits historically associated with their presence. An urban landscape presents prairie dogs with movement challenges unparalleled in natural landscapes, as well as suites of nonnative plant species that are more common in disturbed areas. This study examined a complex ecosystem where vegetation communities are being influenced by directional environmental change, and quantified the synergistic effects resulting from the protective management of a native keystone species. The data set for this analysis was comprised of 71 paired (occupied by prairie dogs vs. unoccupied) vegetation surveys and 156 additional unpaired surveys collected from around the city of Boulder, Colorado, USA for 14 yr. Linear mixed models were used to compare data from transects occupied and unoccupied by prairie dogs, as well as to evaluate the effect of prairie dog occupation duration. In the absence of prairie dogs, vegetation in this region exhibited declines in native grasses, no changes in introduced grasses, and increases in native and nonnative forbs and bare soil over the study interval. In the presence of prairie dogs, these observed directional changes were nearly all amplified at rates four to 10 times greater than when prairie dogs were absent. Areas in Boulder occupied by prairie dogs also had significantly lower richness, evenness, and diversity of plant species, compared to unoccupied areas. Analysis of plant functional groups revealed the significant reduction of perennial native grasses, as well as a significantly higher cover of introduced forbs in occupied areas. Prairie dogs

  16. Surprising quantum bounces

    CERN Document Server

    Nesvizhevsky, Valery

    2015-01-01

    This unique book demonstrates the undivided unity and infinite diversity of quantum mechanics using a single phenomenon: quantum bounces of ultra-cold particles. Various examples of such "quantum bounces" are: gravitational quantum states of ultra-cold neutrons (the first observed quantum states of matter in a gravitational field), the neutron whispering gallery (an observed matter-wave analog of the whispering gallery effect well known in acoustics and for electromagnetic waves), and gravitational and whispering gallery states for anti-matter atoms that remain to be observed. These quantum states are an invaluable tool in the search for additional fundamental short-range forces, for exploring the gravitational interaction and quantum effects of gravity, for probing physics beyond the standard model, and for furthering studies into the foundations of quantum mechanics, quantum optics, and surface science.

  17. More statistics, less surprise

    CERN Multimedia

    Antonella Del Rosso & the LHCb collaboration

    2013-01-01

    The LHCb collaboration has recently announced new results for a parameter that measures the CP violation effect in particles containing charm quarks. The new values obtained with a larger data set and with a new independent method are showing that the effect is smaller than previous measurements had  suggested. The parameter is back into the Standard Model picture.   CP violation signals – in particles containing charm quarks, such as the D0 particle, is a powerful probe of new physics. Indeed, such effects could result in unexpected values of parameters whose expectation values in the Standard Model are known. Although less precise than similar approaches used in particles made of b quarks, the investigation of the charm system has proven  to be intriguing. The LHCb collaboration has reported new measurements of ΔACP, the difference in CP violation between the D0→K+K– and D0→π+π– decays. The results are ob...

  18. Surprise... Surprise..., An Empirical Investigation on How Surprise is Connected to Customer Satisfaction

    NARCIS (Netherlands)

    J. Vanhamme (Joëlle)

    2003-01-01

    textabstractThis research investigates the specific influence of the emotion of surprise on customer transaction-specific satisfaction. Four empirical studies-two field studies (a diary study and a cross section survey) and two experiments-were conducted. The results show that surprise positively

  19. Surprise as a design strategy

    NARCIS (Netherlands)

    Ludden, G.D.S.; Schifferstein, H.N.J.; Hekkert, P.P.M.

    2008-01-01

    Imagine yourself queuing for the cashier’s desk in a supermarket. Naturally, you have picked the wrong line, the one that does not seem to move at all. Soon, you get tired of waiting. Now, how would you feel if the cashier suddenly started to sing? Many of us would be surprised and, regardless of

  20. Semantic relation vs. surprise: the differential effects of related and unrelated co-verbal gestures on neural encoding and subsequent recognition.

    Science.gov (United States)

    Straube, Benjamin; Meyer, Lea; Green, Antonia; Kircher, Tilo

    2014-06-03

    Speech-associated gesturing leads to memory advantages for spoken sentences. However, unexpected or surprising events are also likely to be remembered. With this study we test the hypothesis that different neural mechanisms (semantic elaboration and surprise) lead to memory advantages for iconic and unrelated gestures. During fMRI-data acquisition participants were presented with video clips of an actor verbalising concrete sentences accompanied by iconic gestures (IG; e.g., circular gesture; sentence: "The man is sitting at the round table"), unrelated free gestures (FG; e.g., unrelated up down movements; same sentence) and no gestures (NG; same sentence). After scanning, recognition performance for the three conditions was tested. Videos were evaluated regarding semantic relation and surprise by a different group of participants. The semantic relationship between speech and gesture was rated higher for IG (IG>FG), whereas surprise was rated higher for FG (FG>IG). Activation of the hippocampus correlated with subsequent memory performance of both gesture conditions (IG+FG>NG). For the IG condition we found activation in the left temporal pole and middle cingulate cortex (MCC; IG>FG). In contrast, for the FG condition posterior thalamic structures (FG>IG) as well as anterior and posterior cingulate cortices were activated (FG>NG). Our behavioral and fMRI-data suggest different mechanisms for processing related and unrelated co-verbal gestures, both of them leading to enhanced memory performance. Whereas activation in MCC and left temporal pole for iconic co-verbal gestures may reflect semantic memory processes, memory enhancement for unrelated gestures relies on the surprise response, mediated by anterior/posterior cingulate cortex and thalamico-hippocampal structures. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Surprising Ripple Effects: How Changing the SAT Score-Sending Policy for Low-Income Students Impacts College Access and Success

    Science.gov (United States)

    Hurwitz, Michael; Mbekeani, Preeya P.; Nipson, Margaret M.; Page, Lindsay C.

    2017-01-01

    Subtle policy adjustments can induce relatively large "ripple effects." We evaluate a College Board initiative that increased the number of free SAT score reports available to low-income students and changed the time horizon for using these score reports. Using a difference-in-differences analytic strategy, we estimate that targeted…

  2. A surprising palmar nevus: A case report

    Directory of Open Access Journals (Sweden)

    Rana Rafiei

    2018-02-01

    Full Text Available Raised palmar or plantar nevus especially in white people is an unusual feature. We present an uncommon palmar compound nevus in a 26-year-old woman with a large diameter (6 mm which had a collaret-shaped margin. In histopathologic evaluation intralymphatic protrusions of nevic nests were noted. This case was surprising to us for these reasons: size, shape, location and histopathology of the lesion. Palmar nevi are usually junctional (flat and below 3 mm diameter and intra lymphatic protrusion or invasion in nevi is an extremely rare phenomenon.

  3. Some Surprising Introductory Physics Facts and Numbers

    Science.gov (United States)

    Mallmann, A. James

    2016-01-01

    In the entertainment world, people usually like, and find memorable, novels, short stories, and movies with surprise endings. This suggests that classroom teachers might want to present to their students examples of surprising facts associated with principles of physics. Possible benefits of finding surprising facts about principles of physics are…

  4. Pupil size tracks perceptual content and surprise.

    Science.gov (United States)

    Kloosterman, Niels A; Meindertsma, Thomas; van Loon, Anouk M; Lamme, Victor A F; Bonneh, Yoram S; Donner, Tobias H

    2015-04-01

    Changes in pupil size at constant light levels reflect the activity of neuromodulatory brainstem centers that control global brain state. These endogenously driven pupil dynamics can be synchronized with cognitive acts. For example, the pupil dilates during the spontaneous switches of perception of a constant sensory input in bistable perceptual illusions. It is unknown whether this pupil dilation only indicates the occurrence of perceptual switches, or also their content. Here, we measured pupil diameter in human subjects reporting the subjective disappearance and re-appearance of a physically constant visual target surrounded by a moving pattern ('motion-induced blindness' illusion). We show that the pupil dilates during the perceptual switches in the illusion and a stimulus-evoked 'replay' of that illusion. Critically, the switch-related pupil dilation encodes perceptual content, with larger amplitude for disappearance than re-appearance. This difference in pupil response amplitude enables prediction of the type of report (disappearance vs. re-appearance) on individual switches (receiver-operating characteristic: 61%). The amplitude difference is independent of the relative durations of target-visible and target-invisible intervals and subjects' overt behavioral report of the perceptual switches. Further, we show that pupil dilation during the replay also scales with the level of surprise about the timing of switches, but there is no evidence for an interaction between the effects of surprise and perceptual content on the pupil response. Taken together, our results suggest that pupil-linked brain systems track both the content of, and surprise about, perceptual events. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  5. Large-scale biophysical evaluation of protein PEGylation effects

    DEFF Research Database (Denmark)

    Vernet, Erik; Popa, Gina; Pozdnyakova, Irina

    2016-01-01

    PEGylation is the most widely used method to chemically modify protein biopharmaceuticals, but surprisingly limited public data is available on the biophysical effects of protein PEGylation. Here we report the first large-scale study, with site-specific mono-PEGylation of 15 different proteins...... of PEGylation on the thermal stability of a protein based on data generated by circular dichroism (CD), differential scanning calorimetry (DSC), or differential scanning fluorimetry (DSF). In addition, DSF was validated as a fast and inexpensive screening method for thermal unfolding studies of PEGylated...... proteins. Multivariate data analysis revealed clear trends in biophysical properties upon PEGylation for a subset of proteins, although no universal trends were found. Taken together, these findings are important in the consideration of biophysical methods and evaluation of second...

  6. The role of surprise in satisfaction judgements

    NARCIS (Netherlands)

    Vanhamme, J.; Snelders, H.M.J.J.

    2001-01-01

    Empirical findings suggest that surprise plays an important role in consumer satisfaction, but there is a lack of theory to explain why this is so. The present paper provides explanations for the process through which positive (negative) surprise might enhance (reduce) consumer satisfaction. First,

  7. Centrifugal force: a few surprises

    International Nuclear Information System (INIS)

    Abramowicz, M.A.; Max-Planck-Institut fuer Physik und Astrophysik, Garching

    1990-01-01

    The need for a rather fundamental revision in understanding of the nature of the centrifugal force is discussed. It is shown that in general relativity (and contrary to the situation in Newtonian theory) rotation of a reference frame is a necessary but not sufficient condition for the centrifugal force to appear. A sufficient condition for its appearance, in the instantaneously corotating reference frame of a particle, is that the particle motion in space (observed in the global rest frame) differs from a photon trajectory. The direction of the force is the same as that of the gradient of the effective potential for photon motion. In some cases, the centrifugal force will attract towards the axis of rotation. (author)

  8. Climate Change as a Predictable Surprise

    International Nuclear Information System (INIS)

    Bazerman, M.H.

    2006-01-01

    In this article, I analyze climate change as a 'predictable surprise', an event that leads an organization or nation to react with surprise, despite the fact that the information necessary to anticipate the event and its consequences was available (Bazerman and Watkins, 2004). I then assess the cognitive, organizational, and political reasons why society fails to implement wise strategies to prevent predictable surprises generally and climate change specifically. Finally, I conclude with an outline of a set of response strategies to overcome barriers to change

  9. Environmental effects and large space systems

    Science.gov (United States)

    Garrett, H. B.

    1981-01-01

    When planning large scale operations in space, environmental impact must be considered in addition to radiation, spacecraft charging, contamination, high power and size. Pollution of the atmosphere and space is caused by rocket effluents and by photoelectrons generated by sunlight falling on satellite surfaces even light pollution may result (the SPS may reflect so much light as to be a nuisance to astronomers). Large (100 Km 2) structures also will absorb the high energy particles that impinge on them. Altogether, these effects may drastically alter the Earth's magnetosphere. It is not clear if these alterations will in any way affect the Earth's surface climate. Large structures will also generate large plasma wakes and waves which may cause interference with communications to the vehicle. A high energy, microwave beam from the SPS will cause ionospheric turbulence, affecting UHF and VHF communications. Although none of these effects may ultimately prove critical, they must be considered in the design of large structures.

  10. A toolkit for detecting technical surprise.

    Energy Technology Data Exchange (ETDEWEB)

    Trahan, Michael Wayne; Foehse, Mark C.

    2010-10-01

    The detection of a scientific or technological surprise within a secretive country or institute is very difficult. The ability to detect such surprises would allow analysts to identify the capabilities that could be a military or economic threat to national security. Sandia's current approach utilizing ThreatView has been successful in revealing potential technological surprises. However, as data sets become larger, it becomes critical to use algorithms as filters along with the visualization environments. Our two-year LDRD had two primary goals. First, we developed a tool, a Self-Organizing Map (SOM), to extend ThreatView and improve our understanding of the issues involved in working with textual data sets. Second, we developed a toolkit for detecting indicators of technical surprise in textual data sets. Our toolkit has been successfully used to perform technology assessments for the Science & Technology Intelligence (S&TI) program.

  11. Surprisal analysis and probability matrices for rotational energy transfer

    International Nuclear Information System (INIS)

    Levine, R.D.; Bernstein, R.B.; Kahana, P.; Procaccia, I.; Upchurch, E.T.

    1976-01-01

    The information-theoretic approach is applied to the analysis of state-to-state rotational energy transfer cross sections. The rotational surprisal is evaluated in the usual way, in terms of the deviance of the cross sections from their reference (''prior'') values. The surprisal is found to be an essentially linear function of the energy transferred. This behavior accounts for the experimentally observed exponential gap law for the hydrogen halide systems. The data base here analyzed (taken from the literature) is largely computational in origin: quantal calculations for the hydrogenic systems H 2 +H, He, Li + ; HD+He; D 2 +H and for the N 2 +Ar system; and classical trajectory results for H 2 +Li + ; D 2 +Li + and N 2 +Ar. The surprisal analysis not only serves to compact a large body of data but also aids in the interpretation of the results. A single surprisal parameter theta/subR/ suffices to account for the (relative) magnitude of all state-to-state inelastic cross sections at a given energy

  12. Surprise: a belief or an emotion?

    Science.gov (United States)

    Mellers, Barbara; Fincher, Katrina; Drummond, Caitlin; Bigony, Michelle

    2013-01-01

    Surprise is a fundamental link between cognition and emotion. It is shaped by cognitive assessments of likelihood, intuition, and superstition, and it in turn shapes hedonic experiences. We examine this connection between cognition and emotion and offer an explanation called decision affect theory. Our theory predicts the affective consequences of mistaken beliefs, such as overconfidence and hindsight. It provides insight about why the pleasure of a gain can loom larger than the pain of a comparable loss. Finally, it explains cross-cultural differences in emotional reactions to surprising events. By changing the nature of the unexpected (from chance to good luck), one can alter the emotional reaction to surprising events. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Exploring the concept of climate surprises. A review of the literature on the concept of surprise and how it is related to climate change

    International Nuclear Information System (INIS)

    Glantz, M.H.; Moore, C.M.; Streets, D.G.; Bhatti, N.; Rosa, C.H.

    1998-01-01

    This report examines the concept of climate surprise and its implications for environmental policymaking. Although most integrated assessment models of climate change deal with average values of change, it is usually the extreme events or surprises that cause the most damage to human health and property. Current models do not help the policymaker decide how to deal with climate surprises. This report examines the literature of surprise in many aspects of human society: psychology, military, health care, humor, agriculture, etc. It draws together various ways to consider the concept of surprise and examines different taxonomies of surprise that have been proposed. In many ways, surprise is revealed to be a subjective concept, triggered by such factors as prior experience, belief system, and level of education. How policymakers have reacted to specific instances of climate change or climate surprise in the past is considered, particularly with regard to the choices they made between proactive and reactive measures. Finally, the report discusses techniques used in the current generation of assessment models and makes suggestions as to how climate surprises might be included in future models. The report concludes that some kinds of surprises are simply unpredictable, but there are several types that could in some way be anticipated and assessed, and their negative effects forestalled

  14. Exploring the concept of climate surprises. A review of the literature on the concept of surprise and how it is related to climate change

    Energy Technology Data Exchange (ETDEWEB)

    Glantz, M.H.; Moore, C.M. [National Center for Atmospheric Research, Boulder, CO (United States); Streets, D.G.; Bhatti, N.; Rosa, C.H. [Argonne National Lab., IL (United States). Decision and Information Sciences Div.; Stewart, T.R. [State Univ. of New York, Albany, NY (United States)

    1998-01-01

    This report examines the concept of climate surprise and its implications for environmental policymaking. Although most integrated assessment models of climate change deal with average values of change, it is usually the extreme events or surprises that cause the most damage to human health and property. Current models do not help the policymaker decide how to deal with climate surprises. This report examines the literature of surprise in many aspects of human society: psychology, military, health care, humor, agriculture, etc. It draws together various ways to consider the concept of surprise and examines different taxonomies of surprise that have been proposed. In many ways, surprise is revealed to be a subjective concept, triggered by such factors as prior experience, belief system, and level of education. How policymakers have reacted to specific instances of climate change or climate surprise in the past is considered, particularly with regard to the choices they made between proactive and reactive measures. Finally, the report discusses techniques used in the current generation of assessment models and makes suggestions as to how climate surprises might be included in future models. The report concludes that some kinds of surprises are simply unpredictable, but there are several types that could in some way be anticipated and assessed, and their negative effects forestalled.

  15. Human amygdala response to dynamic facial expressions of positive and negative surprise.

    Science.gov (United States)

    Vrticka, Pascal; Lordier, Lara; Bediou, Benoît; Sander, David

    2014-02-01

    Although brain imaging evidence accumulates to suggest that the amygdala plays a key role in the processing of novel stimuli, only little is known about its role in processing expressed novelty conveyed by surprised faces, and even less about possible interactive encoding of novelty and valence. Those investigations that have already probed human amygdala involvement in the processing of surprised facial expressions either used static pictures displaying negative surprise (as contained in fear) or "neutral" surprise, and manipulated valence by contextually priming or subjectively associating static surprise with either negative or positive information. Therefore, it still remains unresolved how the human amygdala differentially processes dynamic surprised facial expressions displaying either positive or negative surprise. Here, we created new artificial dynamic 3-dimensional facial expressions conveying surprise with an intrinsic positive (wonderment) or negative (fear) connotation, but also intrinsic positive (joy) or negative (anxiety) emotions not containing any surprise, in addition to neutral facial displays either containing ("typical surprise" expression) or not containing ("neutral") surprise. Results showed heightened amygdala activity to faces containing positive (vs. negative) surprise, which may either correspond to a specific wonderment effect as such, or to the computation of a negative expected value prediction error. Findings are discussed in the light of data obtained from a closely matched nonsocial lottery task, which revealed overlapping activity within the left amygdala to unexpected positive outcomes. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  16. Effects of combustible stacking in large compartments

    DEFF Research Database (Denmark)

    Gentili, Filippo; Giuliani, Luisa; Bontempi, Franco

    2013-01-01

    This paper focuses on the modelling of fire in case of various distributions of combustible materials in a large compartment. Large compartments often represent a challenge for structural fire safety, because of lack of prescriptive rules to follow and difficulties of taking into account the effect...... of non uniform distribution of the combustible materials and fire propagation. These aspects are discussed in this paper with reference to an industrial steel building, taken as case study. Fires triggered by the burning of wooden pallets stored in the premises have been investigated with respect...

  17. Viral marketing: the use of surprise

    NARCIS (Netherlands)

    Lindgreen, A.; Vanhamme, J.; Clarke, I.; Flaherty, T.B.

    2005-01-01

    Viral marketing involves consumers passing along a company's marketing message to their friends, family, and colleagues. This chapter reviews viral marketing campaigns and argues that the emotion of surprise often is at work and that this mechanism resembles that of word-of-mouth marketing.

  18. Exploration, Novelty, Surprise and Free Energy Minimisation

    Directory of Open Access Journals (Sweden)

    Philipp eSchwartenbeck

    2013-10-01

    Full Text Available This paper reviews recent developments under the free energy principle that introduce a normative perspective on classical economic (utilitarian decision-making based on (active Bayesian inference. It has been suggested that the free energy principle precludes novelty and complexity, because it assumes that biological systems – like ourselves - try to minimise the long-term average of surprise to maintain their homeostasis. However, recent formulations show that minimising surprise leads naturally to concepts such as exploration and novelty bonuses. In this approach, agents infer a policy that minimises surprise by minimising the difference (or relative entropy between likely and desired outcomes, which involves both pursuing the goal-state that has the highest expected utility (often termed ‘exploitation’ and visiting a number of different goal-states (‘exploration’. Crucially, the opportunity to visit new states increases the value of the current state. Casting decision-making problems within a variational framework, therefore, predicts that our behaviour is governed by both the entropy and expected utility of future states. This dissolves any dialectic between minimising surprise and exploration or novelty seeking.

  19. Glial heterotopia of maxilla: A clinical surprise

    Directory of Open Access Journals (Sweden)

    Santosh Kumar Mahalik

    2011-01-01

    Full Text Available Glial heterotopia is a rare congenital mass lesion which often presents as a clinical surprise. We report a case of extranasal glial heterotopia in a neonate with unusual features. The presentation, management strategy, etiopathogenesis and histopathology of the mass lesion has been reviewed.

  20. A Shocking Surprise in Stephan's Quintet

    Science.gov (United States)

    2006-01-01

    This false-color composite image of the Stephan's Quintet galaxy cluster clearly shows one of the largest shock waves ever seen (green arc). The wave was produced by one galaxy falling toward another at speeds of more than one million miles per hour. The image is made up of data from NASA's Spitzer Space Telescope and a ground-based telescope in Spain. Four of the five galaxies in this picture are involved in a violent collision, which has already stripped most of the hydrogen gas from the interiors of the galaxies. The centers of the galaxies appear as bright yellow-pink knots inside a blue haze of stars, and the galaxy producing all the turmoil, NGC7318b, is the left of two small bright regions in the middle right of the image. One galaxy, the large spiral at the bottom left of the image, is a foreground object and is not associated with the cluster. The titanic shock wave, larger than our own Milky Way galaxy, was detected by the ground-based telescope using visible-light wavelengths. It consists of hot hydrogen gas. As NGC7318b collides with gas spread throughout the cluster, atoms of hydrogen are heated in the shock wave, producing the green glow. Spitzer pointed its infrared spectrograph at the peak of this shock wave (middle of green glow) to learn more about its inner workings. This instrument breaks light apart into its basic components. Data from the instrument are referred to as spectra and are displayed as curving lines that indicate the amount of light coming at each specific wavelength. The Spitzer spectrum showed a strong infrared signature for incredibly turbulent gas made up of hydrogen molecules. This gas is caused when atoms of hydrogen rapidly pair-up to form molecules in the wake of the shock wave. Molecular hydrogen, unlike atomic hydrogen, gives off most of its energy through vibrations that emit in the infrared. This highly disturbed gas is the most turbulent molecular hydrogen ever seen. Astronomers were surprised not only by the turbulence

  1. Effective string dynamics in large N QCD

    Energy Technology Data Exchange (ETDEWEB)

    Iroshnikov, G.S. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]|[Moskow Inst. of Physics and Technology, Moscow (Russian Federation)

    1995-05-01

    The semiclassical 1/N expansion in the strong coupling regime for spinor quarks was developed and the form of effective action was obtained. An extremum of the effective action that arises in the calculation of the hadronic correlation functions in the large N limit corresponds to a topologically non-trivial configuration of the gauge field. This configuration forms a chromoelectric Nambu string with additional spinor terms that contain in particular the Polyakov spinor factor. In the case when real quarks forming hadrons are replaced by scalar particles the above correlators yield the standard dual resonance amplitudes. (author). 10 refs, 1 fig.

  2. Radar Design to Protect Against Surprise

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    Technological and doctrinal surprise is about rendering preparations for conflict as irrelevant or ineffective . For a sensor, this means essentially rendering the sensor as irrelevant or ineffective in its ability to help determine truth. Recovery from this sort of surprise is facilitated by flexibility in our own technology and doctrine. For a sensor, this mean s flexibility in its architecture, design, tactics, and the designing organizations ' processes. - 4 - Acknowledgements This report is the result of a n unfunded research and development activity . Sandia National Laboratories is a multi - program laboratory manage d and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000.

  3. Surprise: Dwarf Galaxy Harbors Supermassive Black Hole

    Science.gov (United States)

    2011-01-01

    The surprising discovery of a supermassive black hole in a small nearby galaxy has given astronomers a tantalizing look at how black holes and galaxies may have grown in the early history of the Universe. Finding a black hole a million times more massive than the Sun in a star-forming dwarf galaxy is a strong indication that supermassive black holes formed before the buildup of galaxies, the astronomers said. The galaxy, called Henize 2-10, 30 million light-years from Earth, has been studied for years, and is forming stars very rapidly. Irregularly shaped and about 3,000 light-years across (compared to 100,000 for our own Milky Way), it resembles what scientists think were some of the first galaxies to form in the early Universe. "This galaxy gives us important clues about a very early phase of galaxy evolution that has not been observed before," said Amy Reines, a Ph.D. candidate at the University of Virginia. Supermassive black holes lie at the cores of all "full-sized" galaxies. In the nearby Universe, there is a direct relationship -- a constant ratio -- between the masses of the black holes and that of the central "bulges" of the galaxies, leading them to conclude that the black holes and bulges affected each others' growth. Two years ago, an international team of astronomers found that black holes in young galaxies in the early Universe were more massive than this ratio would indicate. This, they said, was strong evidence that black holes developed before their surrounding galaxies. "Now, we have found a dwarf galaxy with no bulge at all, yet it has a supermassive black hole. This greatly strengthens the case for the black holes developing first, before the galaxy's bulge is formed," Reines said. Reines, along with Gregory Sivakoff and Kelsey Johnson of the University of Virginia and the National Radio Astronomy Observatory (NRAO), and Crystal Brogan of the NRAO, observed Henize 2-10 with the National Science Foundation's Very Large Array radio telescope and

  4. Old Star's "Rebirth" Gives Astronomers Surprises

    Science.gov (United States)

    2005-04-01

    Astronomers using the National Science Foundation's Very Large Array (VLA) radio telescope are taking advantage of a once-in-a-lifetime opportunity to watch an old star suddenly stir back into new activity after coming to the end of its normal life. Their surprising results have forced them to change their ideas of how such an old, white dwarf star can re-ignite its nuclear furnace for one final blast of energy. Sakurai's Object Radio/Optical Images of Sakurai's Object: Color image shows nebula ejected thousands of years ago. Contours indicate radio emission. Inset is Hubble Space Telescope image, with contours indicating radio emission; this inset shows just the central part of the region. CREDIT: Hajduk et al., NRAO/AUI/NSF, ESO, StSci, NASA Computer simulations had predicted a series of events that would follow such a re-ignition of fusion reactions, but the star didn't follow the script -- events moved 100 times more quickly than the simulations predicted. "We've now produced a new theoretical model of how this process works, and the VLA observations have provided the first evidence supporting our new model," said Albert Zijlstra, of the University of Manchester in the United Kingdom. Zijlstra and his colleagues presented their findings in the April 8 issue of the journal Science. The astronomers studied a star known as V4334 Sgr, in the constellation Sagittarius. It is better known as "Sakurai's Object," after Japanese amateur astronomer Yukio Sakurai, who discovered it on February 20, 1996, when it suddenly burst into new brightness. At first, astronomers thought the outburst was a common nova explosion, but further study showed that Sakurai's Object was anything but common. The star is an old white dwarf that had run out of hydrogen fuel for nuclear fusion reactions in its core. Astronomers believe that some such stars can undergo a final burst of fusion in a shell of helium that surrounds a core of heavier nuclei such as carbon and oxygen. However, the

  5. Revisiting the Effectiveness of Large Optical Telescopes

    Directory of Open Access Journals (Sweden)

    V. V. Sychev

    2015-01-01

    back action of design elements and propagation medium on the transmitted radiation wave-front;- lack of a basic source of radiation on the laser radiation wavelength, which is necessary for the adaptive correction methods to be applied to distorted wave-front;- inherent only in laser systems additional distorting factors available in transmitting systems.Such distorting factors are as follows:• length of optical path because of spacing necessary for a high-power laser source with a large number of the consistent optical elements;• thermal self-influence of powerful laser radiation in the channel of radiation transportation before its input in the forming optical system;• instability of spatiotemporal characteristics of laser radiation source itself, which worsens passing radiation conditions both in an optical path and in the free atmosphere;• thermal heterogeneity and thermal deformations.It is shown that adaptive systems are distinguished from active optics by the fact that correction of the radiation wave-front distortions occurs in real time on the entire set of the distorting factors (not only on influence of the atmosphere with the speed much exceeding action of distortions. Thus, the quality correction is assessed according to criterion of quality of primary image.Thus, correction continuously considers information on the current spatial, temperature, temporary, and justified parameters of the optical system, providing quality maintenance of the image under conditions of distorting factors.The main postulates of adaptive correction are formulated and offered.Postulates represent the set of statements and provisions allowing us to realize effective remedies of adaptive correction of distortions.It is also shown what real opportunities are open by using methods and means of adaptive optics in effective application of laser radiation power and what ways allow us to solve these tasks. First of all, it is:- forming a system of assumptions and minimizing the

  6. Primary Care Practice: Uncertainty and Surprise

    Science.gov (United States)

    Crabtree, Benjamin F.

    I will focus my comments on uncertainty and surprise in primary care practices. I am a medical anthropologist by training, and have been a full-time researcher in family medicine for close to twenty years. In this talk I want to look at primary care practices as complex systems, particularly taking the perspective of translating evidence into practice. I am going to discuss briefly the challenges we have in primary care, and in medicine in general, of translating new evidence into the everyday care of patients. To do this, I will look at two studies that we have conducted on family practices, then think about how practices can be best characterized as complex adaptive systems. Finally, I will focus on the implications of this portrayal for disseminating new knowledge into practice.

  7. Surprises and counterexamples in real function theory

    CERN Document Server

    Rajwade, A R

    2007-01-01

    This book presents a variety of intriguing, surprising and appealing topics and nonroutine theorems in real function theory. It is a reference book to which one can turn for finding that arise while studying or teaching analysis.Chapter 1 is an introduction to algebraic, irrational and transcendental numbers and contains the Cantor ternary set. Chapter 2 contains functions with extraordinary properties; functions that are continuous at each point but differentiable at no point. Chapters 4 and intermediate value property, periodic functions, Rolle's theorem, Taylor's theorem, points of tangents. Chapter 6 discusses sequences and series. It includes the restricted harmonic series, of alternating harmonic series and some number theoretic aspects. In Chapter 7, the infinite peculiar range of convergence is studied. Appendix I deal with some specialized topics. Exercises at the end of chapters and their solutions are provided in Appendix II.This book will be useful for students and teachers alike.

  8. A Neural Mechanism for Surprise-related Interruptions of Visuospatial Working Memory.

    Science.gov (United States)

    Wessel, Jan R

    2018-01-01

    Surprising perceptual events recruit a fronto-basal ganglia mechanism for inhibition, which suppresses motor activity following surprise. A recent study found that this inhibitory mechanism also disrupts the maintenance of verbal working memory (WM) after surprising tones. However, it is unclear whether this same mechanism also relates to surprise-related interruptions of non-verbal WM. We tested this hypothesis using a change-detection task, in which surprising tones impaired visuospatial WM. Participants also performed a stop-signal task (SST). We used independent component analysis and single-trial scalp-electroencephalogram to test whether the same inhibitory mechanism that reflects motor inhibition in the SST relates to surprise-related visuospatial WM decrements, as was the case for verbal WM. As expected, surprising tones elicited activity of the inhibitory mechanism, and this activity correlated strongly with the trial-by-trial level of surprise. However, unlike for verbal WM, the activity of this mechanism was unrelated to visuospatial WM accuracy. Instead, inhibition-independent activity that immediately succeeded the inhibitory mechanism was increased when visuospatial WM was disrupted. This shows that surprise-related interruptions of visuospatial WM are not effected by the same inhibitory mechanism that interrupts verbal WM, and instead provides evidence for a 2-stage model of distraction. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. The conceptualization model problem—surprise

    Science.gov (United States)

    Bredehoeft, John

    2005-03-01

    The foundation of model analysis is the conceptual model. Surprise is defined as new data that renders the prevailing conceptual model invalid; as defined here it represents a paradigm shift. Limited empirical data indicate that surprises occur in 20-30% of model analyses. These data suggest that groundwater analysts have difficulty selecting the appropriate conceptual model. There is no ready remedy to the conceptual model problem other than (1) to collect as much data as is feasible, using all applicable methods—a complementary data collection methodology can lead to new information that changes the prevailing conceptual model, and (2) for the analyst to remain open to the fact that the conceptual model can change dramatically as more information is collected. In the final analysis, the hydrogeologist makes a subjective decision on the appropriate conceptual model. The conceptualization problem does not render models unusable. The problem introduces an uncertainty that often is not widely recognized. Conceptual model uncertainty is exacerbated in making long-term predictions of system performance. C'est le modèle conceptuel qui se trouve à base d'une analyse sur un modèle. On considère comme une surprise lorsque le modèle est invalidé par des données nouvelles; dans les termes définis ici la surprise est équivalente à un change de paradigme. Des données empiriques limitées indiquent que les surprises apparaissent dans 20 à 30% des analyses effectuées sur les modèles. Ces données suggèrent que l'analyse des eaux souterraines présente des difficultés lorsqu'il s'agit de choisir le modèle conceptuel approprié. Il n'existe pas un autre remède au problème du modèle conceptuel que: (1) rassembler autant des données que possible en utilisant toutes les méthodes applicables—la méthode des données complémentaires peut conduire aux nouvelles informations qui vont changer le modèle conceptuel, et (2) l'analyste doit rester ouvert au fait

  10. X rays and radioactivity: a complete surprise

    International Nuclear Information System (INIS)

    Radvanyi, P.; Bordry, M.

    1995-01-01

    The discoveries of X rays and of radioactivity came as complete experimental surprises; the physicists, at that time, had no previous hint of a possible structure of atoms. It is difficult now, knowing what we know, to replace ourselves in the spirit, astonishment and questioning of these years, between 1895 and 1903. The nature of X rays was soon hypothesized, but the nature of the rays emitted by uranium, polonium and radium was much more difficult to disentangle, as they were a mixture of different types of radiations. The origin of the energy continuously released in radioactivity remained a complete mystery for a few years. The multiplicity of the radioactive substances became soon a difficult matter: what was real and what was induced ? Isotopy was still far ahead. It appeared that some radioactive substances had ''half-lifes'': were they genuine radioactive elements or was it just a transitory phenomenon ? Henri Becquerel (in 1900) and Pierre and Marie Curie (in 1902) hesitated on the correct answer. Only after Ernest Rutherford and Frederick Soddy established that radioactivity was the transmutation of one element into another, could one understand that a solid element transformed into a gaseous element, which in turn transformed itself into a succession of solid radioactive elements. It was only in 1913 - after the discovery of the atomic nucleus -, through precise measurements of X ray spectra, that Henry Moseley showed that the number of electrons of a given atom - and the charge of its nucleus - was equal to its atomic number in the periodic table. (authors)

  11. X rays and radioactivity: a complete surprise

    Energy Technology Data Exchange (ETDEWEB)

    Radvanyi, P. [Laboratoire National Saturne, Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France); Bordry, M. [Institut du Radium, 75 - Paris (France)

    1995-12-31

    The discoveries of X rays and of radioactivity came as complete experimental surprises; the physicists, at that time, had no previous hint of a possible structure of atoms. It is difficult now, knowing what we know, to replace ourselves in the spirit, astonishment and questioning of these years, between 1895 and 1903. The nature of X rays was soon hypothesized, but the nature of the rays emitted by uranium, polonium and radium was much more difficult to disentangle, as they were a mixture of different types of radiations. The origin of the energy continuously released in radioactivity remained a complete mystery for a few years. The multiplicity of the radioactive substances became soon a difficult matter: what was real and what was induced ? Isotopy was still far ahead. It appeared that some radioactive substances had ``half-lifes``: were they genuine radioactive elements or was it just a transitory phenomenon ? Henri Becquerel (in 1900) and Pierre and Marie Curie (in 1902) hesitated on the correct answer. Only after Ernest Rutherford and Frederick Soddy established that radioactivity was the transmutation of one element into another, could one understand that a solid element transformed into a gaseous element, which in turn transformed itself into a succession of solid radioactive elements. It was only in 1913 - after the discovery of the atomic nucleus -, through precise measurements of X ray spectra, that Henry Moseley showed that the number of electrons of a given atom - and the charge of its nucleus - was equal to its atomic number in the periodic table. (authors).

  12. Surprises in the suddenly-expanded infinite well

    International Nuclear Information System (INIS)

    Aslangul, Claude

    2008-01-01

    I study the time evolution of a particle prepared in the ground state of an infinite well after the latter is suddenly expanded. It turns out that the probability density |Ψ(x, t)| 2 shows up quite a surprising behaviour: for definite times, plateaux appear for which |Ψ(x, t)| 2 is constant on finite intervals for x. Elements of theoretical explanation are given by analysing the singular component of the second derivative ∂ xx Ψ(x, t). Analytical closed expressions are obtained for some specific times, which easily allow us to show that, at these times, the density organizes itself into regular patterns provided the size of the box is large enough; more, above some critical size depending on the specific time, the density patterns are independent of the expansion parameter. It is seen how the density at these times simply results from a construction game with definite rules acting on the pieces of the initial density

  13. The Value of Change: Surprises and Insights in Stellar Evolution

    Science.gov (United States)

    Bildsten, Lars

    2018-01-01

    Astronomers with large-format cameras regularly scan the sky many times per night to detect what's changing, and telescopes in space such as Kepler and, soon, TESS obtain very accurate brightness measurements of nearly a million stars over time periods of years. These capabilities, in conjunction with theoretical and computational efforts, have yielded surprises and remarkable new insights into the internal properties of stars and how they end their lives. I will show how asteroseismology reveals the properties of the deep interiors of red giants, and highlight how astrophysical transients may be revealing unusual thermonuclear outcomes from exploding white dwarfs and the births of highly magnetic neutron stars. All the while, stellar science has been accelerated by the availability of open source tools, such as Modules for Experiments in Stellar Astrophysics (MESA), and the nearly immediate availability of observational results.

  14. Large cutoff effects of dynamical Wilson fermions

    International Nuclear Information System (INIS)

    Sommer, R.; Hoffmann, R.; Knechtli, F.; Rolf, J.; Wolff, U.; Wetzorke, I.

    2003-09-01

    We present and discuss results for cutoff effects in the PCAC masses and the mass dependence of r 0 for full QCD and various fermion actions. Our discussion of how one computes mass dependences - here of r 0 - is also relevant for comparisons with chiral perturbation theory. (orig.)

  15. Toroidal field ripple effects in large tokamaks

    International Nuclear Information System (INIS)

    Uckan, N.A.; Tsang, K.T.; Callen, J.D.

    1975-01-01

    In an experimental power reactor, the ripple produced by the finite number of toroidal field coils destroys the ideal axisymmetry of the configuration and is responsible for additional particle trapping, loss regions and plasma transport. The effects of toroidal field ripple on the plasma transport coefficient, the loss of alpha particles and energetic injection ions, and the relaxation of toroidal flows are investigated in a new and systematic way. The relevant results are applied to the ORNL-EPR reference design; the maximum ripple there of about 2.2 percent at the outer edge of the plasma column is found to be tolerable from plasma physics considerations

  16. Fundamental surprise in the application of airpower

    Science.gov (United States)

    2017-05-25

    explain transformations in scientific research proposed by Thomas Kuhn in his book “The Structure of Scientific Revolutions." Kuhn proposed the idea...that the accepted traditions of scientific research within a particular community, known as a paradigm, provide the tools to perform "normal science...the large-scale attacks on Lebanese infrastructure would have on the regime, this concept was a non- starter . The order issued to the IDF on 12 July

  17. The Influence of Negative Surprise on Hedonic Adaptation

    Directory of Open Access Journals (Sweden)

    Ana Paula Kieling

    2016-01-01

    Full Text Available After some time using a product or service, the consumer tends to feel less pleasure with consumption. This reduction of pleasure is known as hedonic adaptation. One of the emotions that interfere in this process is surprise. Based on two experiments, we suggest that negative surprise – differently to positive – influences with the level of pleasure foreseen and experienced by the consumer. Study 1 analyzes the influence of negative (vs. positive surprise on the consumer’s post-purchase hedonic adaptation expectation. Results showed that negative surprise influences the intensity of adaptation, augmenting its strength. Study 2 verifies the influence of negative (vs positive surprise over hedonic adaptation. The findings suggested that negative surprise makes adaptation happen more intensively and faster as time goes by, which brings consequences to companies and consumers in the post-purchase process, such as satisfaction and loyalty.

  18. A Dichotomic Analysis of the Surprise Examination Paradox

    OpenAIRE

    Franceschi, Paul

    2002-01-01

    This paper presents a dichotomic analysis of the surprise examination paradox. In section 1, I analyse the surprise notion in detail. I introduce then in section 2, the distinction between a monist and dichotomic analysis of the paradox. I also present there a dichotomy leading to distinguish two basically and structurally different versions of the paradox, respectively based on a conjoint and a disjoint definition of the surprise. In section 3, I describe the solution to SEP corresponding to...

  19. An undiagnosed pleural effusion with surprising consequences

    Directory of Open Access Journals (Sweden)

    A.G. Casalini

    2017-01-01

    With this case report, we would like to underline the importance of making a correct diagnosis of any pleural effusion as soon as possible by at least a thoracocentesis. If untreated, tuberculosis may easily disseminate to other organs. Some considerations and suggestions for antibiotic treatment of pleural effusion will also be given, since many antibiotics have some anti-tuberculosis effect and may delay the diagnosis of this infectious disease.

  20. A surprise case of colonic interposition

    International Nuclear Information System (INIS)

    Law, Robert

    2006-01-01

    Blind nasogastric intubation failure as a result of changes to the normal anatomical pathway is not uncommon. This case report is of fluoroscopically guided intubation in a patient in whom blind intubation failed as a result of what was subsequently found to be a colonic interposition with associated late complications. Fluroscopically guided nasogastric intubation is a safe and effective procedure that should always be considered when blind intubation has failed

  1. Older Galaxy Pair Has Surprisingly Youthful Glow

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Poster Version A pair of interacting galaxies might be experiencing the galactic equivalent of a mid-life crisis. For some reason, the pair, called Arp 82, didn't make their stars early on as is typical of most galaxies. Instead, they got a second wind later in life -- about 2 billion years ago -- and started pumping out waves of new stars as if they were young again. Arp 82 is an interacting pair of galaxies with a strong bridge and a long tail. NGC 2535 is the big galaxy and NGC 2536 is its smaller companion. The disk of the main galaxy looks like an eye, with a bright 'pupil' in the center and oval-shaped 'eyelids.' Dramatic 'beads on a string' features are visible as chains of evenly spaced star-formation complexes along the eyelids. These are presumably the result of large-scale gaseous shocks from a grazing encounter. The colors of this galaxy indicate that the observed stars are young to intermediate in age, around 2 million to 2 billion years old, much less than the age of the universe (13.7 billion years). The puzzle is: why didn't Arp 82 form many stars earlier, like most galaxies of that mass range? Scientifically, it is an oddball and provides a relatively nearby lab for studying the age of intermediate-mass galaxies. This picture is a composite captured by Spitzer's infrared array camera with light at wavelength 8 microns shown in red, NASA's Galaxy Evolution Explorer combined 1530 and 2310 Angstroms shown in blue, and the Southeastern Association for Research in Astronomy Observatory light at 6940 Angstroms shown in green.

  2. Smartphone Response System Using Twitter to Enable Effective Interaction and Improve Engagement in Large Classrooms

    Science.gov (United States)

    Kim, Yeongjun; Jeong, Soonmook; Ji, Yongwoon; Lee, Sangeun; Kwon, Key Ho; Jeon, Jae Wook

    2015-01-01

    This paper proposes a method for seamless interaction between students and their professor using Twitter, one of the typical social network service (SNS) platforms, in large lectures. During the lecture, the professor poses surprise questions in the form of a quiz on an overhead screen at unexpected moments, and students submit their answers…

  3. The Value of Surprising Findings for Research on Marketing

    OpenAIRE

    JS Armstrong

    2004-01-01

    In the work of Armstrong (Journal of Business Research, 2002), I examined empirical research on the scientific process and related these to marketing science. The findings of some studies were surprising. In this reply, I address surprising findings and other issues raised by commentators.

  4. Comment exploiter les 'corpus-surprise' ?

    Directory of Open Access Journals (Sweden)

    Rittaud-Hutinet, Chantal

    2009-01-01

    Full Text Available To what extent non-recorded oral corpora may constitute objects of analysis of pragmatic meaning?These corpora are heard by chance: on the radio, on television, in the street, a shop, a means of transport or generally in any conversational interaction in which the linguist participates, but had not previously planned to record for his research. The problem of the use of these corpora in linguistics is all the more crucial since the aim, in phonopragmatics, is to discover the functions and significations of their phonic part. I shall attempt to answer the following questions:–The accuracy of the transcription with respect to the original. To what extent can we ignore our own phonological code, our regional variants, mastered/partly known styles of speech?–The reliability of the oral reproduction carried out by the linguist – for example, during a talk at a conference. What is his capacity for deferred mimicry?–The relation between a significant discrepancy and the elocutionary habits of the speaker.–The relation between the comprehension of the external auditors and the effect produced on the 'real' person addressed.Considering that transparency is (sometimes? often? an illusion, I shall also examine what precautions should be taken so that these corpora offer guarantees as to the veracity.

  5. Corrugator Activity Confirms Immediate Negative Affect in Surprise

    Directory of Open Access Journals (Sweden)

    Sascha eTopolinski

    2015-02-01

    Full Text Available The emotion of surprise entails a complex of immediate responses, such as cognitive interruption, attention allocation to, and more systematic processing of the surprising stimulus. All these processes serve the ultimate function to increase processing depth and thus cognitively master the surprising stimulus. The present account introduces phasic negative affect as the underlying mechanism responsible for these consequences. Surprising stimuli are schema-discrepant and thus entail cognitive disfluency, which elicits immediate negative affect. This affect in turn works like a phasic cognitive tuning switching the current processing mode from more automatic and heuristic to more systematic and reflective processing. Directly testing the initial elicitation of negative affect by suprising events, the present experiment presented high and low surprising neutral trivia statements to N = 28 participants while assessing their spontaneous facial expressions via facial electromyography. High compared to low suprising trivia elicited higher corrugator activity, indicative of negative affect and mental effort, while leaving zygomaticus (positive affect and frontalis (cultural surprise expression activity unaffected. Future research shall investigate the mediating role of negative affect in eliciting surprise-related outcomes.

  6. Surprise Gift” Purchases of Small Electric Appliances: A Pilot Study

    NARCIS (Netherlands)

    J. Vanhamme (Joëlle); C.J.P.M. de Bont (Cees)

    2005-01-01

    textabstractUnderstanding decision-making processes for gifts is of strategic importance for companies selling small electrical appliances as gifts account for a large part of their sales. Among all gifts, the ones that are surprising are the most valued by recipients. However, research about

  7. A large mixing effect on eta,eta' and iota

    International Nuclear Information System (INIS)

    Kawai, E.

    1983-01-01

    We quantitatively investigate a possible large mixing effect on eta(549), eta'(958) and iota(1440) in a phenomenological way, taking both SU(3) symmetry breaking and gluon intervention into due account. (orig.)

  8. Managing Uncertainity: Soviet Views on Deception, Surprise, and Control

    National Research Council Canada - National Science Library

    Hull, Andrew

    1989-01-01

    .... In the first two cases (deception and surprise), the emphasis is on how the Soviets seek to sow uncertainty in the minds of the enemy and how the Soviets then plan to use that uncertainty to gain military advantage...

  9. Dividend announcements reconsidered: Dividend changes versus dividend surprises

    OpenAIRE

    Andres, Christian; Betzer, André; van den Bongard, Inga; Haesner, Christian; Theissen, Erik

    2012-01-01

    This paper reconsiders the issue of share price reactions to dividend announcements. Previous papers rely almost exclusively on a naive dividend model in which the dividend change is used as a proxy for the dividend surprise. We use the difference between the actual dividend and the analyst consensus forecast as obtained from I/B/E/S as a proxy for the dividend surprise. Using data from Germany, we find significant share price reactions after dividend announcements. Once we control for analys...

  10. The Surprise Examination Paradox and the Second Incompleteness Theorem

    OpenAIRE

    Kritchman, Shira; Raz, Ran

    2010-01-01

    We give a new proof for Godel's second incompleteness theorem, based on Kolmogorov complexity, Chaitin's incompleteness theorem, and an argument that resembles the surprise examination paradox. We then go the other way around and suggest that the second incompleteness theorem gives a possible resolution of the surprise examination paradox. Roughly speaking, we argue that the flaw in the derivation of the paradox is that it contains a hidden assumption that one can prove the consistency of the...

  11. Atom Surprise: Using Theatre in Primary Science Education

    Science.gov (United States)

    Peleg, Ran; Baram-Tsabari, Ayelet

    2011-10-01

    Early exposure to science may have a lifelong effect on children's attitudes towards science and their motivation to learn science in later life. Out-of-class environments can play a significant role in creating favourable attitudes, while contributing to conceptual learning. Educational science theatre is one form of an out-of-class environment, which has received little research attention. This study aims to describe affective and cognitive learning outcomes of watching such a play and to point to connections between theatrical elements and specific outcomes. "Atom Surprise" is a play portraying several concepts on the topic of matter. A mixed methods approach was adopted to investigate the knowledge and attitudes of children (grades 1-6) from two different school settings who watched the play. Data were gathered using questionnaires and in-depth interviews. Analysis suggested that in both schools children's knowledge on the topic of matter increased after the play with younger children gaining more conceptual knowledge than their older peers. In the public school girls showed greater gains in conceptual knowledge than boys. No significant changes in students' general attitudes towards science were found, however, students demonstrated positive changes towards science learning. Theatrical elements that seemed to be important in children's recollection of the play were the narrative, props and stage effects, and characters. In the children's memory, science was intertwined with the theatrical elements. Nonetheless, children could distinguish well between scientific facts and the fictive narrative.

  12. Identifying demand effects in a large network of product categories

    NARCIS (Netherlands)

    Gelper, S.E.C.; Wilms, I.; Croux, C.

    2016-01-01

    Planning marketing mix strategies requires retailers to understand within- as well as cross-category demand effects. Most retailers carry products in a large variety of categories, leading to a high number of such demand effects to be estimated. At the same time, we do not expect cross-category

  13. Optimal counterterrorism and the recruitment effect of large terrorist attacks

    DEFF Research Database (Denmark)

    Jensen, Thomas

    2011-01-01

    We analyze a simple dynamic model of the interaction between terrorists and authorities. Our primary aim is to study optimal counterterrorism and its consequences when large terrorist attacks lead to a temporary increase in terrorist recruitment. First, we show that an increase in counterterrorism...... makes it more likely that terrorist cells plan small rather than large attacks and therefore may increase the probability of a successful attack. Analyzing optimal counterterrorism we see that the recruitment effect makes authorities increase the level of counterterrorism after large attacks. Therefore......, in periods following large attacks a new attack is more likely to be small compared to other periods. Finally, we analyze the long-run consequences of the recruitment effect. We show that it leads to more counterterrorism, more small attacks, and a higher sum of terrorism damage and counterterrorism costs...

  14. Estimation and Inference for Very Large Linear Mixed Effects Models

    OpenAIRE

    Gao, K.; Owen, A. B.

    2016-01-01

    Linear mixed models with large imbalanced crossed random effects structures pose severe computational problems for maximum likelihood estimation and for Bayesian analysis. The costs can grow as fast as $N^{3/2}$ when there are N observations. Such problems arise in any setting where the underlying factors satisfy a many to many relationship (instead of a nested one) and in electronic commerce applications, the N can be quite large. Methods that do not account for the correlation structure can...

  15. The effects of large beach debris on nesting sea turtles

    Science.gov (United States)

    Fujisaki, Ikuko; Lamont, Margaret M.

    2016-01-01

    A field experiment was conducted to understand the effects of large beach debris on sea turtle nesting behavior as well as the effectiveness of large debris removal for habitat restoration. Large natural and anthropogenic debris were removed from one of three sections of a sea turtle nesting beach and distributions of nests and false crawls (non-nesting crawls) in pre- (2011–2012) and post- (2013–2014) removal years in the three sections were compared. The number of nests increased 200% and the number of false crawls increased 55% in the experimental section, whereas a corresponding increase in number of nests and false crawls was not observed in the other two sections where debris removal was not conducted. The proportion of nest and false crawl abundance in all three beach sections was significantly different between pre- and post-removal years. The nesting success, the percent of successful nests in total nesting attempts (number of nests + false crawls), also increased from 24% to 38%; however the magnitude of the increase was comparably small because both the number of nests and false crawls increased, and thus the proportion of the nesting success in the experimental beach in pre- and post-removal years was not significantly different. The substantial increase in sea turtle nesting activities after the removal of large debris indicates that large debris may have an adverse impact on sea turtle nesting behavior. Removal of large debris could be an effective restoration strategy to improve sea turtle nesting.

  16. An efficient community detection algorithm using greedy surprise maximization

    International Nuclear Information System (INIS)

    Jiang, Yawen; Jia, Caiyan; Yu, Jian

    2014-01-01

    Community detection is an important and crucial problem in complex network analysis. Although classical modularity function optimization approaches are widely used for identifying communities, the modularity function (Q) suffers from its resolution limit. Recently, the surprise function (S) was experimentally proved to be better than the Q function. However, up until now, there has been no algorithm available to perform searches to directly determine the maximal surprise values. In this paper, considering the superiority of the S function over the Q function, we propose an efficient community detection algorithm called AGSO (algorithm based on greedy surprise optimization) and its improved version FAGSO (fast-AGSO), which are based on greedy surprise optimization and do not suffer from the resolution limit. In addition, (F)AGSO does not need the number of communities K to be specified in advance. Tests on experimental networks show that (F)AGSO is able to detect optimal partitions in both simple and even more complex networks. Moreover, algorithms based on surprise maximization perform better than those algorithms based on modularity maximization, including Blondel–Guillaume–Lambiotte–Lefebvre (BGLL), Clauset–Newman–Moore (CNM) and the other state-of-the-art algorithms such as Infomap, order statistics local optimization method (OSLOM) and label propagation algorithm (LPA). (paper)

  17. Large magnetoresistance effect in nitrogen-doped silicon

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2017-05-01

    Full Text Available In this work, we reported a large magnetoresistance effect in silicon by ion implantation of nitrogen atoms. At room temperature, the magnetoresistance of silicon reaches 125 % under magnetic field 1.7 T and voltage bias -80 V. By applying an alternating magnetic field with a frequency (f of 0.008 Hz, we find that the magnetoresistance of silicon is divided into f and 2f two signal components, which represent the linear and quadratic magnetoresistance effects, respectively. The analysis based on tuning the magnetic field and the voltage bias reveals that electric-field-induced space-charge effect plays an important role to enhance both the linear and quadratic magnetoresistance effects. Observation as well as a comprehensive explanation of large MR in silicon, especially based on semiconductor CMOS implantation technology, will be an important progress towards magnetoelectronic applications.

  18. Models of Automation surprise : results of a field survey in aviation

    NARCIS (Netherlands)

    De Boer, Robert; Dekker, Sidney

    2017-01-01

    Automation surprises in aviation continue to be a significant safety concern and the community’s search for effective strategies to mitigate them are ongoing. The literature has offered two fundamentally divergent directions, based on different ideas about the nature of cognition and collaboration

  19. Surprise and Memory as Indices of Concrete Operational Development

    Science.gov (United States)

    Achenbach, Thomas M.

    1973-01-01

    Normal and retarded children's use of color, number, length and continuous quantity as attributes of identification was assessed by presenting them with contrived changes in three properties. Surprise and correct memory responses for color preceded those to number, which preceded logical verbal responses to a conventional number-conservation task.…

  20. Things may not be as expected: Surprising findings when updating ...

    African Journals Online (AJOL)

    2015-05-14

    May 14, 2015 ... Things may not be as expected: Surprising findings when updating .... (done at the end of three months after the first review month) ..... Allen G. Getting beyond form filling: The role of institutional governance in human research ...

  1. Automation surprise : results of a field survey of Dutch pilots

    NARCIS (Netherlands)

    de Boer, R.J.; Hurts, Karel

    2017-01-01

    Automation surprise (AS) has often been associated with aviation safety incidents. Although numerous laboratory studies have been conducted, few data are available from routine flight operations. A survey among a representative sample of 200 Dutch airline pilots was used to determine the prevalence

  2. Effects of large herbivores on grassland arthropod diversity.

    Science.gov (United States)

    van Klink, R; van der Plas, F; van Noordwijk, C G E Toos; WallisDeVries, M F; Olff, H

    2015-05-01

    Both arthropods and large grazing herbivores are important components and drivers of biodiversity in grassland ecosystems, but a synthesis of how arthropod diversity is affected by large herbivores has been largely missing. To fill this gap, we conducted a literature search, which yielded 141 studies on this topic of which 24 simultaneously investigated plant and arthropod diversity. Using the data from these 24 studies, we compared the responses of plant and arthropod diversity to an increase in grazing intensity. This quantitative assessment showed no overall significant effect of increasing grazing intensity on plant diversity, while arthropod diversity was generally negatively affected. To understand these negative effects, we explored the mechanisms by which large herbivores affect arthropod communities: direct effects, changes in vegetation structure, changes in plant community composition, changes in soil conditions, and cascading effects within the arthropod interaction web. We identify three main factors determining the effects of large herbivores on arthropod diversity: (i) unintentional predation and increased disturbance, (ii) decreases in total resource abundance for arthropods (biomass) and (iii) changes in plant diversity, vegetation structure and abiotic conditions. In general, heterogeneity in vegetation structure and abiotic conditions increases at intermediate grazing intensity, but declines at both low and high grazing intensity. We conclude that large herbivores can only increase arthropod diversity if they cause an increase in (a)biotic heterogeneity, and then only if this increase is large enough to compensate for the loss of total resource abundance and the increased mortality rate. This is expected to occur only at low herbivore densities or with spatio-temporal variation in herbivore densities. As we demonstrate that arthropod diversity is often more negatively affected by grazing than plant diversity, we strongly recommend considering the

  3. Large scale obscuration and related climate effects open literature bibliography

    International Nuclear Information System (INIS)

    Russell, N.A.; Geitgey, J.; Behl, Y.K.; Zak, B.D.

    1994-05-01

    Large scale obscuration and related climate effects of nuclear detonations first became a matter of concern in connection with the so-called ''Nuclear Winter Controversy'' in the early 1980's. Since then, the world has changed. Nevertheless, concern remains about the atmospheric effects of nuclear detonations, but the source of concern has shifted. Now it focuses less on global, and more on regional effects and their resulting impacts on the performance of electro-optical and other defense-related systems. This bibliography reflects the modified interest

  4. Large scale obscuration and related climate effects open literature bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Russell, N.A.; Geitgey, J.; Behl, Y.K.; Zak, B.D.

    1994-05-01

    Large scale obscuration and related climate effects of nuclear detonations first became a matter of concern in connection with the so-called ``Nuclear Winter Controversy`` in the early 1980`s. Since then, the world has changed. Nevertheless, concern remains about the atmospheric effects of nuclear detonations, but the source of concern has shifted. Now it focuses less on global, and more on regional effects and their resulting impacts on the performance of electro-optical and other defense-related systems. This bibliography reflects the modified interest.

  5. The effective field theory of cosmological large scale structures

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, John Joseph M. [Stanford Univ., Stanford, CA (United States); Hertzberg, Mark P. [Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States); Senatore, Leonardo [Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2012-09-20

    Large scale structure surveys will likely become the next leading cosmological probe. In our universe, matter perturbations are large on short distances and small at long scales, i.e. strongly coupled in the UV and weakly coupled in the IR. To make precise analytical predictions on large scales, we develop an effective field theory formulated in terms of an IR effective fluid characterized by several parameters, such as speed of sound and viscosity. These parameters, determined by the UV physics described by the Boltzmann equation, are measured from N-body simulations. We find that the speed of sound of the effective fluid is c2s ≈ 10–6c2 and that the viscosity contributions are of the same order. The fluid describes all the relevant physics at long scales k and permits a manifestly convergent perturbative expansion in the size of the matter perturbations δ(k) for all the observables. As an example, we calculate the correction to the power spectrum at order δ(k)4. As a result, the predictions of the effective field theory are found to be in much better agreement with observation than standard cosmological perturbation theory, already reaching percent precision at this order up to a relatively short scale k ≃ 0.24h Mpc–1.

  6. Isolating relativistic effects in large-scale structure

    Science.gov (United States)

    Bonvin, Camille

    2014-12-01

    We present a fully relativistic calculation of the observed galaxy number counts in the linear regime. We show that besides the density fluctuations and redshift-space distortions, various relativistic effects contribute to observations at large scales. These effects all have the same physical origin: they result from the fact that our coordinate system, namely the galaxy redshift and the incoming photons’ direction, is distorted by inhomogeneities in our Universe. We then discuss the impact of the relativistic effects on the angular power spectrum and on the two-point correlation function in configuration space. We show that the latter is very well adapted to isolate the relativistic effects since it naturally makes use of the symmetries of the different contributions. In particular, we discuss how the Doppler effect and the gravitational redshift distortions can be isolated by looking for a dipole in the cross-correlation function between a bright and a faint population of galaxies.

  7. Renormalization in Large Momentum Effective Theory of Parton Physics.

    Science.gov (United States)

    Ji, Xiangdong; Zhang, Jian-Hui; Zhao, Yong

    2018-03-16

    In the large-momentum effective field theory approach to parton physics, the matrix elements of nonlocal operators of quark and gluon fields, linked by straight Wilson lines in a spatial direction, are calculated in lattice quantum chromodynamics as a function of hadron momentum. Using the heavy-quark effective theory formalism, we show a multiplicative renormalization of these operators at all orders in perturbation theory, both in dimensional and lattice regularizations. The result provides a theoretical basis for extracting parton properties through properly renormalized observables in Monte Carlo simulations.

  8. Neutron flux shape effects in large fast reactor safety calculations

    International Nuclear Information System (INIS)

    Galati, A.; Loizzo, P.; Musco, A.

    1978-01-01

    Three classes of accidents in a large fast reactor were studied by the two-dimensional core dynamics code NADYP-2. A Modified version of the code, including a point kinetics module, allowed comparison between 2D and 0D power, reactivity and temperature histories. A strong shape effect was evidenced by these calculations in the boiling phase of LOF accidents as well as in the accident generated by control rod removal. Some future possibilities of by passing the consequences of this effect are indicated

  9. Monitoring the effects of floods on submerged macrophytes in a large river.

    Science.gov (United States)

    Ibáñez, Carles; Caiola, Nuno; Rovira, Albert; Real, Montserrat

    2012-12-01

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton to a macrophyte-dominated system. Macrophytes started to spread at the end of the 1990s and since 2002 artificial floods (flushing flows) of short duration (1-2 days) are released from the Riba-roja dam once or twice a year in order to reduce macrophyte density. The aim of this study was to analyse the spatiotemporal trends of the submerged macrophytes in two stretches of the lower Ebro River using high-resolution hydroacoustic methods, in order to elucidate the effects of artificial floods and natural floods on its distribution and abundance. Results showed that the mean cover in the two studied stretches (Móra and Ginestar) was not reduced after a flushing flow (from 36.59% to 55.85% in Móra, and from 21.18% to 21.05% in Ginestar), but it was greatly reduced after the natural flood (down to 9.79% in Móra and 2.04% in Ginestar); surprisingly the cover increased in Móra after the artificial flood. In order to increase the efficiency of floods in controlling macrophyte spreading, the magnitude and frequency of them should largely increase, as well as the suspended sediment load, approaching as much as possible to the original flood pattern before dam construction. Hydroacoustic methods combined with geostatistics and interpolation in GIS can accurately monitor spatiotemporal trends of submerged macrophytes in large rivers. This is the first article to apply this monitoring system to submerged macrophytes in rivers. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Quantum tunneling observed without its characteristic large kinetic isotope effects.

    Science.gov (United States)

    Hama, Tetsuya; Ueta, Hirokazu; Kouchi, Akira; Watanabe, Naoki

    2015-06-16

    Classical transition-state theory is fundamental to describing chemical kinetics; however, quantum tunneling is also important in explaining the unexpectedly large reaction efficiencies observed in many chemical systems. Tunneling is often indicated by anomalously large kinetic isotope effects (KIEs), because a particle's ability to tunnel decreases significantly with its increasing mass. Here we experimentally demonstrate that cold hydrogen (H) and deuterium (D) atoms can add to solid benzene by tunneling; however, the observed H/D KIE was very small (1-1.5) despite the large intrinsic H/D KIE of tunneling (≳ 100). This strong reduction is due to the chemical kinetics being controlled not by tunneling but by the surface diffusion of the H/D atoms, a process not greatly affected by the isotope type. Because tunneling need not be accompanied by a large KIE in surface and interfacial chemical systems, it might be overlooked in other systems such as aerosols or enzymes. Our results suggest that surface tunneling reactions on interstellar dust may contribute to the deuteration of interstellar aromatic and aliphatic hydrocarbons, which could represent a major source of the deuterium enrichment observed in carbonaceous meteorites and interplanetary dust particles. These findings could improve our understanding of interstellar physicochemical processes, including those during the formation of the solar system.

  11. The Ultraviolet Surprise. Efficient Soft X-Ray High Harmonic Generation in Multiply-Ionized Plasmas

    International Nuclear Information System (INIS)

    Popmintchev, Dimitar; Hernandez-Garcia, Carlos; Dollar, Franklin; Mancuso, Christopher; Perez-Hernandez, Jose A.; Chen, Ming-Chang; Hankla, Amelia; Gao, Xiaohui; Shim, Bonggu; Gaeta, Alexander L.; Tarazkar, Maryam; Romanov, Dmitri A.; Levis, Robert J.; Gaffney, Jim A.; Foord, Mark; Libby, Stephen B.; Jaron-Becker, Agnieskzka; Becker, Andreas; Plaja, Luis; Muranane, Margaret M.; Kapteyn, Henry C.; Popmintchev, Tenio

    2015-01-01

    High-harmonic generation is a universal response of matter to strong femtosecond laser fields, coherently upconverting light to much shorter wavelengths. Optimizing the conversion of laser light into soft x-rays typically demands a trade-off between two competing factors. Reduced quantum diffusion of the radiating electron wave function results in emission from each species which is highest when a short-wavelength ultraviolet driving laser is used. But, phase matching - the constructive addition of x-ray waves from a large number of atoms - favors longer-wavelength mid-infrared lasers. We identified a regime of high-harmonic generation driven by 40-cycle ultraviolet lasers in waveguides that can generate bright beams in the soft x-ray region of the spectrum, up to photon energies of 280 electron volts. Surprisingly, the high ultraviolet refractive indices of both neutral atoms and ions enabled effective phase matching, even in a multiply ionized plasma. We observed harmonics with very narrow linewidths, while calculations show that the x-rays emerge as nearly time-bandwidt-limited pulse trains of ~100 attoseconds

  12. Sleeping beauties in theoretical physics 26 surprising insights

    CERN Document Server

    Padmanabhan, Thanu

    2015-01-01

    This book addresses a fascinating set of questions in theoretical physics which will both entertain and enlighten all students, teachers and researchers and other physics aficionados. These range from Newtonian mechanics to quantum field theory and cover several puzzling issues that do not appear in standard textbooks. Some topics cover conceptual conundrums, the solutions to which lead to surprising insights; some correct popular misconceptions in the textbook discussion of certain topics; others illustrate deep connections between apparently unconnected domains of theoretical physics; and a few provide remarkably simple derivations of results which are not often appreciated. The connoisseur of theoretical physics will enjoy a feast of pleasant surprises skilfully prepared by an internationally acclaimed theoretical physicist. Each topic is introduced with proper background discussion and special effort is taken to make the discussion self-contained, clear and comprehensible to anyone with an undergraduate e...

  13. The June surprises: balls, strikes, and the fog of war.

    Science.gov (United States)

    Fried, Charles

    2013-04-01

    At first, few constitutional experts took seriously the argument that the Patient Protection and Affordable Care Act exceeded Congress's power under the commerce clause. The highly political opinions of two federal district judges - carefully chosen by challenging plaintiffs - of no particular distinction did not shake that confidence that the act was constitutional. This disdain for the challengers' arguments was only confirmed when the act was upheld by two highly respected conservative court of appeals judges in two separate circuits. But after the hostile, even mocking questioning of the government's advocate in the Supreme Court by the five Republican-appointed justices, the expectation was that the act would indeed be struck down on that ground. So it came as no surprise when the five opined the act did indeed exceed Congress's commerce clause power. But it came as a great surprise when Chief Justice John Roberts, joined by the four Democrat-appointed justices, ruled that the act could be sustained as an exercise of Congress's taxing power - a ground urged by the government almost as an afterthought. It was further surprising, even shocking, that Justices Antonin Scalia, Anthony Kennedy, Clarence Thomas, and Samuel Alito not only wrote a joint opinion on the commerce clause virtually identical to that of their chief, but that in writing it they did not refer to or even acknowledge his opinion. Finally surprising was the fact that Justices Ruth Bader Ginsburg and Stephen Breyer joined the chief in holding that aspects of the act's Medicaid expansion were unconstitutional. This essay ponders and tries to unravel some of these puzzles.

  14. ORMS IN SURPRISING PLACES: CLINICAL AND MORPHOLOGICAL FEATURES

    Directory of Open Access Journals (Sweden)

    Myroshnychenko MS

    2013-06-01

    Full Text Available Helminthes are the most common human diseases, which are characterized by involvement in the pathological process of all organs and systems. In this article, the authors discuss a few cases of typical and atypical localizations for parasitic worms such as filarial and pinworms which were recovered from surprising places in the bodies of patients in Kharkiv region. This article will allow the doctors of practical health care to pay special attention to the timely prevention and diagnostics of this pathology.

  15. Decision-making under surprise and uncertainty: Arsenic contamination of water supplies

    Science.gov (United States)

    Randhir, Timothy O.; Mozumder, Pallab; Halim, Nafisa

    2018-05-01

    With ignorance and potential surprise dominating decision making in water resources, a framework for dealing with such uncertainty is a critical need in hydrology. We operationalize the 'potential surprise' criterion proposed by Shackle, Vickers, and Katzner (SVK) to derive decision rules to manage water resources under uncertainty and ignorance. We apply this framework to managing water supply systems in Bangladesh that face severe, naturally occurring arsenic contamination. The uncertainty involved with arsenic in water supplies makes the application of conventional analysis of decision-making ineffective. Given the uncertainty and surprise involved in such cases, we find that optimal decisions tend to favor actions that avoid irreversible outcomes instead of conventional cost-effective actions. We observe that a diversification of the water supply system also emerges as a robust strategy to avert unintended outcomes of water contamination. Shallow wells had a slight higher optimal level (36%) compare to deep wells and surface treatment which had allocation levels of roughly 32% under each. The approach can be applied in a variety of other cases that involve decision making under uncertainty and surprise, a frequent situation in natural resources management.

  16. Surprising results: HIV testing and changes in contraceptive practices among young women in Malawi

    Science.gov (United States)

    Sennott, Christie; Yeatman, Sara

    2015-01-01

    This study uses eight waves of data from the population-based Tsogolo la Thanzi study (2009–2011) in rural Malawi to examine changes in young women’s contraceptive practices, including the use of condoms, non-barrier contraceptive methods, and abstinence, following positive and negative HIV tests. The analysis factors in women’s prior perceptions of their HIV status that may already be shaping their behaviour and separates surprise HIV test results from those that merely confirm what was already believed. Fixed effects logistic regression models show that HIV testing frequently affects the contraceptive practices of young Malawian women, particularly when the test yields an unexpected result. Specifically, women who are surprised to test HIV positive increase their condom use and are more likely to use condoms consistently. Following an HIV negative test (whether a surprise or expected), women increase their use of condoms and decrease their use of non-barrier contraceptives; the latter may be due to an increase in abstinence following a surprise negative result. Changes in condom use following HIV testing are robust to the inclusion of potential explanatory mechanisms including fertility preferences, relationship status, and the perception that a partner is HIV positive. The results demonstrate that both positive and negative tests can influence women’s sexual and reproductive behaviours, and emphasise the importance of conceptualizing of HIV testing as offering new information only insofar as results deviate from prior perceptions of HIV status. PMID:26160156

  17. Spatiotemporal neural characterization of prediction error valence and surprise during reward learning in humans.

    Science.gov (United States)

    Fouragnan, Elsa; Queirazza, Filippo; Retzler, Chris; Mullinger, Karen J; Philiastides, Marios G

    2017-07-06

    Reward learning depends on accurate reward associations with potential choices. These associations can be attained with reinforcement learning mechanisms using a reward prediction error (RPE) signal (the difference between actual and expected rewards) for updating future reward expectations. Despite an extensive body of literature on the influence of RPE on learning, little has been done to investigate the potentially separate contributions of RPE valence (positive or negative) and surprise (absolute degree of deviation from expectations). Here, we coupled single-trial electroencephalography with simultaneously acquired fMRI, during a probabilistic reversal-learning task, to offer evidence of temporally overlapping but largely distinct spatial representations of RPE valence and surprise. Electrophysiological variability in RPE valence correlated with activity in regions of the human reward network promoting approach or avoidance learning. Electrophysiological variability in RPE surprise correlated primarily with activity in regions of the human attentional network controlling the speed of learning. Crucially, despite the largely separate spatial extend of these representations our EEG-informed fMRI approach uniquely revealed a linear superposition of the two RPE components in a smaller network encompassing visuo-mnemonic and reward areas. Activity in this network was further predictive of stimulus value updating indicating a comparable contribution of both signals to reward learning.

  18. Stars Form Surprisingly Close to Milky Way's Black Hole

    Science.gov (United States)

    2005-10-01

    million low mass, sun-like stars in and around the ring, whereas in the disk model, the number of low mass stars could be much less. Nayakshin and his coauthor, Rashid Sunyaev of the Max Plank Institute for Physics in Garching, Germany, used Chandra observations to compare the X-ray glow from the region around Sgr A* to the X-ray emission from thousands of young stars in the Orion Nebula star cluster. They found that the Sgr A* star cluster contains only about 10,000 low mass stars, thereby ruling out the migration model. "We can now say that the stars around Sgr A* were not deposited there by some passing star cluster, rather they were born there," said Sunyaev . "There have been theories that this was possible, but this is the first real evidence. Many scientists are going to be very surprised by these results." Because the Galactic Center is shrouded in dust and gas, it has not been possible to look for the low-mass stars in optical observations. In contrast, X-ray data have allowed astronomers to penetrate the veil of gas and dust and look for these low mass stars. Scenario Dismissed by Chandra Results Scenario Dismissed by Chandra Results "In one of the most inhospitable places in our Galaxy, stars have prevailed," said Nayakshin. "It appears that star formation is much more tenacious than we previously believed." The results suggest that the "rules" of star formation change when stars form in the disk of a giant black hole. Because this environment is very different from typical star formation regions, there is a change in the proportion of stars that form. For example, there is a much higher percentage of massive stars in the disks around black holes. And, when these massive stars explode as supernovae, they will "fertilize" the region with heavy elements such as oxygen. This may explain the large amounts of such elements observed in the disks of young supermassive black holes. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for

  19. Effects of large bending deflections on blade flutter limits

    Energy Technology Data Exchange (ETDEWEB)

    Kallesoee, Bjarne Skovmose; Hartvig Hansen, Morten

    2008-04-15

    The coupling of bending and torsion due to large blade bending are assumed to have some effects of the flutter limits of wind turbines. In the present report, the aeroelastic blade model suggested by Kallesoee, which is similar to a second order model, is used to investigate the aeroelastic stability limits of the RWT blade with and without the effects of the large blade deflection. The investigation shows no significant change of the flutter limit on the rotor speed due to the blade deflection,whereas the first edgewise bending mode becomes negatively damped due to the coupling with blade torsion which causes a change of the effective direction of blade vibration. These observations are confirmed by nonlinear aeroelastic simulations using HAWC2. This work is part of the UpWind project funded by the European Commission under the contract number SES6-CT-2005-019945 which is gratefully acknowledged. This report is the deliverable D2.3 of the UpWind project. (au)

  20. The effects and consequences of very large explosive volcanic eruptions.

    Science.gov (United States)

    Self, S

    2006-08-15

    Every now and again Earth experiences tremendous explosive volcanic eruptions, considerably bigger than the largest witnessed in historic times. Those yielding more than 450km3 of magma have been called super-eruptions. The record of such eruptions is incomplete; the most recent known example occurred 26000 years ago. It is more likely that the Earth will next experience a super-eruption than an impact from a large meteorite greater than 1km in diameter. Depending on where the volcano is located, the effects will be felt globally or at least by a whole hemisphere. Large areas will be devastated by pyroclastic flow deposits, and the more widely dispersed ash falls will be laid down over continent-sized areas. The most widespread effects will be derived from volcanic gases, sulphur gases being particularly important. This gas is converted into sulphuric acid aerosols in the stratosphere and layers of aerosol can cover the global atmosphere within a few weeks to months. These remain for several years and affect atmospheric circulation causing surface temperature to fall in many regions. Effects include temporary reductions in light levels and severe and unseasonable weather (including cool summers and colder-than-normal winters). Some aspects of the understanding and prediction of super-eruptions are problematic because they are well outside modern experience. Our global society is now very different to that affected by past, modest-sized volcanic activity and is highly vulnerable to catastrophic damage of infrastructure by natural disasters. Major disruption of services that society depends upon can be expected for periods of months to, perhaps, years after the next very large explosive eruption and the cost to global financial markets will be high and sustained.

  1. ESB application for effective synchronization of large volume measurements data

    CERN Document Server

    Wyszkowski, Przemysław Michał

    2011-01-01

    The TOTEM experiment at CERN aims at measurement of total cross section, elastic scattering and diffractive processes of colliding protons in the Large Hadron Collider. In order for the research to be possible, it is necessary to process huge amounts of data coming from variety of sources: TOTEM detectors, CMS detectors, measurement devices around the Large Hadron Collider tunnel and many other external systems. Preparing final results involves also calculating plenty of intermediate figures, which also need to be stored. In order for the work of the scientist to be effective and convenient it is crucial to provide central point for the data storage, where all raw and intermediate figures will be stored. This thesis aims at presenting the usage of Enterprise Service Bus concept in building software infrastructure for transferring large volume of measurements data. Topics discussed here include technologies and mechanisms realizing the concept of integration bus, model of data transferring system based on ...

  2. Fringe field effects in small rings of large acceptance

    Directory of Open Access Journals (Sweden)

    Martin Berz

    2000-12-01

    Full Text Available Recently there has been renewed interest in the influence of fringe fields on particle dynamics, due to studies that revealed their importance in some cases, as, for example, the proposed Neutrino Factory and muon colliders. In this paper, we present a systematic study of generic fringe field effects. Using as an example a lattice of the proposed Neutrino Factory, we show that fringe fields influence the dynamics of particles at all orders, starting with the linear motion. It is found that the widely used sharp cutoff approximation leads to divergences regardless of the specific fall-off shape of the fields. The results suggest that a careful consideration of fringe field effects in the design stage of small machines for large emittances is always recommended.

  3. Large Scale Obscuration and Related Climate Effects Workshop: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Zak, B.D.; Russell, N.A.; Church, H.W.; Einfeld, W.; Yoon, D.; Behl, Y.K. [eds.

    1994-05-01

    A Workshop on Large Scale Obsurcation and Related Climate Effects was held 29--31 January, 1992, in Albuquerque, New Mexico. The objectives of the workshop were: to determine through the use of expert judgement the current state of understanding of regional and global obscuration and related climate effects associated with nuclear weapons detonations; to estimate how large the uncertainties are in the parameters associated with these phenomena (given specific scenarios); to evaluate the impact of these uncertainties on obscuration predictions; and to develop an approach for the prioritization of further work on newly-available data sets to reduce the uncertainties. The workshop consisted of formal presentations by the 35 participants, and subsequent topical working sessions on: the source term; aerosol optical properties; atmospheric processes; and electro-optical systems performance and climatic impacts. Summaries of the conclusions reached in the working sessions are presented in the body of the report. Copies of the transparencies shown as part of each formal presentation are contained in the appendices (microfiche).

  4. Economic valuation of the downstream hydrological effects of land use change: Large hydroelectric reservoirs

    Science.gov (United States)

    Aylward, Bruce Allan

    1998-12-01

    Land use change that accompanies economic development and population growth is intended to raise the economic productivity of land. An inevitable by product of this process is the alteration of natural vegetation and downstream hydrological function. This dissertation explores hydrological externalities of land use change in detail, particularly with regard to their economic impact on large hydroelectric reservoirs (LHRs). A review of the linkages between land use, hydrological function and downstream economic activity suggests that on theoretical grounds the net welfare effect of land use change on hydrological function will be indeterminate. Review of the literature suggests that, though the effects of downstream sedimentation will typically be negative, they may often be of little practical significance. The literature on water quantity impacts is sparse at best. This is most surprising in the case of the literature on LHRs where the potentially important and positive effects of increased water yield are typically ignored in favor of simplistic efforts to document the negative effects of reservoir sedimentation. In order to improve the methodological basis for the economic valuation of hydrological externalities, the dissertation considers existing techniques for the evaluation of non-marketed goods and services, clarifying the manner in which they have been and, in the future, may be applied to the topic at hand. A deterministic simulation model is then constructed for the case of LHRs. The model incorporates the effect of changes in water yield, the seasonal pattern of water yield and sedimentation of live and dead storage volumes as they affect reservoir operation and the production of hydroelectricity. The welfare effects of changes in the productivity of the LHR in the short run and changes to the power system expansion plan in the long run are evaluated using the marginal opportunity costs of alternative power sources and power plants, respectively. A case

  5. On the surprising rigidity of the Pauli exclusion principle

    International Nuclear Information System (INIS)

    Greenberg, O.W.

    1989-01-01

    I review recent attempts to construct a local quantum field theory of small violations of the Pauli exclusion principle and suggest a qualitative reason for the surprising rigidity of the Pauli principle. I suggest that small violations can occur in our four-dimensional world as a consequence of the compactification of a higher-dimensional theory in which the exclusion principle is exactly valid. I briefly mention a recent experiment which places a severe limit on possible violations of the exclusion principle. (orig.)

  6. Teacher Supply and Demand: Surprises from Primary Research

    Directory of Open Access Journals (Sweden)

    Andrew J. Wayne

    2000-09-01

    Full Text Available An investigation of primary research studies on public school teacher supply and demand revealed four surprises. Projections show that enrollments are leveling off. Relatedly, annual hiring increases should be only about two or three percent over the next few years. Results from studies of teacher attrition also yield unexpected results. Excluding retirements, only about one in 20 teachers leaves each year, and the novice teachers who quit mainly cite personal and family reasons, not job dissatisfaction. Each of these findings broadens policy makers' options for teacher supply.

  7. Effective field theories in the large-N limit

    International Nuclear Information System (INIS)

    Weinberg, S.

    1997-01-01

    Various effective field theories in four dimensions are shown to have exact nontrivial solutions in the limit as the number N of fields of some type becomes large. These include extended versions of the U (N) Gross-Neveu model, the nonlinear O(N) σ model, and the CP N-1 model. Although these models are not renormalizable in the usual sense, the infinite number of coupling types allows a complete cancellation of infinities. These models provide qualitative predictions of the form of scattering amplitudes for arbitrary momenta, but because of the infinite number of free parameters, it is possible to derive quantitative predictions only in the limit of small momenta. For small momenta the large-N limit provides only a modest simplification, removing at most a finite number of diagrams to each order in momenta, except near phase transitions, where it reduces the infinite number of diagrams that contribute for low momenta to a finite number. copyright 1997 The American Physical Society

  8. Plasma polarimetry for large Cotton--Mouton and Faraday effects

    International Nuclear Information System (INIS)

    Segre, S.E.

    1995-01-01

    A formalism is presented for treating plasma polarimetry when both the Cotton--Mouton and the Faraday effects are large. For this general case it is shown that, for each measuring chord, up to nine parameters related to the plasma can be determined, instead of the usual single Faraday rotation. These parameters can be measured by a convenient modulation of the polarization state of the input radiation, and they can be used in the reconstruction of the magnetohydrodynamic equilibrium. Thus, the potential of the polarimetric diagnostic can be significantly increased, and the range of plasma conditions where the latter can be used, is extended. The importance of refraction is discussed. copyright 1995 American Institute of Physics

  9. Estimations of expectedness and potential surprise in possibility theory

    Science.gov (United States)

    Prade, Henri; Yager, Ronald R.

    1992-01-01

    This note investigates how various ideas of 'expectedness' can be captured in the framework of possibility theory. Particularly, we are interested in trying to introduce estimates of the kind of lack of surprise expressed by people when saying 'I would not be surprised that...' before an event takes place, or by saying 'I knew it' after its realization. In possibility theory, a possibility distribution is supposed to model the relative levels of mutually exclusive alternatives in a set, or equivalently, the alternatives are assumed to be rank-ordered according to their level of possibility to take place. Four basic set-functions associated with a possibility distribution, including standard possibility and necessity measures, are discussed from the point of view of what they estimate when applied to potential events. Extensions of these estimates based on the notions of Q-projection or OWA operators are proposed when only significant parts of the possibility distribution are retained in the evaluation. The case of partially-known possibility distributions is also considered. Some potential applications are outlined.

  10. The Surprising Impact of Seat Location on Student Performance

    Science.gov (United States)

    Perkins, Katherine K.; Wieman, Carl E.

    2005-01-01

    Every physics instructor knows that the most engaged and successful students tend to sit at the front of the class and the weakest students tend to sit at the back. However, it is normally assumed that this is merely an indication of the respective seat location preferences of weaker and stronger students. Here we present evidence suggesting that in fact this may be mixing up the cause and effect. It may be that the seat selection itself contributes to whether the student does well or poorly, rather than the other way around. While a number of studies have looked at the effect of seat location on students, the results are often inconclusive, and few, if any, have studied the effects in college classrooms with randomly assigned seats. In this paper, we report on our observations of a large introductory physics course in which we randomly assigned students to particular seat locations at the beginning of the semester. Seat location during the first half of the semester had a noticeable impact on student success in the course, particularly in the top and bottom parts of the grade distribution. Students sitting in the back of the room for the first half of the term were nearly six times as likely to receive an F as students who started in the front of the room. A corresponding but less dramatic reversal was evident in the fractions of students receiving As. These effects were in spite of many unusual efforts to engage students at the back of the class and a front-to-back reversal of seat location halfway through the term. These results suggest there may be inherent detrimental effects of large physics lecture halls that need to be further explored.

  11. Models of Automation Surprise: Results of a Field Survey in Aviation

    Directory of Open Access Journals (Sweden)

    Robert De Boer

    2017-09-01

    Full Text Available Automation surprises in aviation continue to be a significant safety concern and the community’s search for effective strategies to mitigate them are ongoing. The literature has offered two fundamentally divergent directions, based on different ideas about the nature of cognition and collaboration with automation. In this paper, we report the results of a field study that empirically compared and contrasted two models of automation surprises: a normative individual-cognition model and a sensemaking model based on distributed cognition. Our data prove a good fit for the sense-making model. This finding is relevant for aviation safety, since our understanding of the cognitive processes that govern human interaction with automation drive what we need to do to reduce the frequency of automation-induced events.

  12. Effects of large herbivores on grassland arthropod diversity

    NARCIS (Netherlands)

    van Klink, R.; van der Plas, F.; van Noordwijk, C. G. E. (Toos); WallisDeVries, M. F.; Olff, H.

    Both arthropods and large grazing herbivores are important components and drivers of biodiversity in grassland ecosystems, but a synthesis of how arthropod diversity is affected by large herbivores has been largely missing. To fill this gap, we conducted a literature search, which yielded 141

  13. Human Amygdala Tracks a Feature-Based Valence Signal Embedded within the Facial Expression of Surprise.

    Science.gov (United States)

    Kim, M Justin; Mattek, Alison M; Bennett, Randi H; Solomon, Kimberly M; Shin, Jin; Whalen, Paul J

    2017-09-27

    Human amygdala function has been traditionally associated with processing the affective valence (negative vs positive) of an emotionally charged event, especially those that signal fear or threat. However, this account of human amygdala function can be explained by alternative views, which posit that the amygdala might be tuned to either (1) general emotional arousal (activation vs deactivation) or (2) specific emotion categories (fear vs happy). Delineating the pure effects of valence independent of arousal or emotion category is a challenging task, given that these variables naturally covary under many circumstances. To circumvent this issue and test the sensitivity of the human amygdala to valence values specifically, we measured the dimension of valence within the single facial expression category of surprise. Given the inherent valence ambiguity of this category, we show that surprised expression exemplars are attributed valence and arousal values that are uniquely and naturally uncorrelated. We then present fMRI data from both sexes, showing that the amygdala tracks these consensus valence values. Finally, we provide evidence that these valence values are linked to specific visual features of the mouth region, isolating the signal by which the amygdala detects this valence information. SIGNIFICANCE STATEMENT There is an open question as to whether human amygdala function tracks the valence value of cues in the environment, as opposed to either a more general emotional arousal value or a more specific emotion category distinction. Here, we demonstrate the utility of surprised facial expressions because exemplars within this emotion category take on valence values spanning the dimension of bipolar valence (positive to negative) at a consistent level of emotional arousal. Functional neuroimaging data showed that amygdala responses tracked the valence of surprised facial expressions, unconfounded by arousal. Furthermore, a machine learning classifier identified

  14. Chandra Finds Surprising Black Hole Activity In Galaxy Cluster

    Science.gov (United States)

    2002-09-01

    Scientists at the Carnegie Observatories in Pasadena, California, have uncovered six times the expected number of active, supermassive black holes in a single viewing of a cluster of galaxies, a finding that has profound implications for theories as to how old galaxies fuel the growth of their central black holes. The finding suggests that voracious, central black holes might be as common in old, red galaxies as they are in younger, blue galaxies, a surprise to many astronomers. The team made this discovery with NASA'S Chandra X-ray Observatory. They also used Carnegie's 6.5-meter Walter Baade Telescope at the Las Campanas Observatory in Chile for follow-up optical observations. "This changes our view of galaxy clusters as the retirement homes for old and quiet black holes," said Dr. Paul Martini, lead author on a paper describing the results that appears in the September 10 issue of The Astrophysical Journal Letters. "The question now is, how do these black holes produce bright X-ray sources, similar to what we see from much younger galaxies?" Typical of the black hole phenomenon, the cores of these active galaxies are luminous in X-ray radiation. Yet, they are obscured, and thus essentially undetectable in the radio, infrared and optical wavebands. "X rays can penetrate obscuring gas and dust as easily as they penetrate the soft tissue of the human body to look for broken bones," said co-author Dr. Dan Kelson. "So, with Chandra, we can peer through the dust and we have found that even ancient galaxies with 10-billion-year-old stars can have central black holes still actively pulling in copious amounts of interstellar gas. This activity has simply been hidden from us all this time. This means these galaxies aren't over the hill after all and our theories need to be revised." Scientists say that supermassive black holes -- having the mass of millions to billions of suns squeezed into a region about the size of our Solar System -- are the engines in the cores of

  15. Effective models of new physics at the Large Hadron Collider

    International Nuclear Information System (INIS)

    Llodra-Perez, J.

    2011-07-01

    With the start of the Large Hadron Collider runs, in 2010, particle physicists will be soon able to have a better understanding of the electroweak symmetry breaking. They might also answer to many experimental and theoretical open questions raised by the Standard Model. Surfing on this really favorable situation, we will first present in this thesis a highly model-independent parametrization in order to characterize the new physics effects on mechanisms of production and decay of the Higgs boson. This original tool will be easily and directly usable in data analysis of CMS and ATLAS, the huge generalist experiments of LHC. It will help indeed to exclude or validate significantly some new theories beyond the Standard Model. In another approach, based on model-building, we considered a scenario of new physics, where the Standard Model fields can propagate in a flat six-dimensional space. The new spatial extra-dimensions will be compactified on a Real Projective Plane. This orbifold is the unique six-dimensional geometry which possesses chiral fermions and a natural Dark Matter candidate. The scalar photon, which is the lightest particle of the first Kaluza-Klein tier, is stabilized by a symmetry relic of the six dimension Lorentz invariance. Using the current constraints from cosmological observations and our first analytical calculation, we derived a characteristic mass range around few hundred GeV for the Kaluza-Klein scalar photon. Therefore the new states of our Universal Extra-Dimension model are light enough to be produced through clear signatures at the Large Hadron Collider. So we used a more sophisticated analysis of particle mass spectrum and couplings, including radiative corrections at one-loop, in order to establish our first predictions and constraints on the expected LHC phenomenology. (author)

  16. Physics Nobel prize 2004: Surprising theory wins physics Nobel

    CERN Multimedia

    2004-01-01

    From left to right: David Politzer, David Gross and Frank Wilczek. For their understanding of counter-intuitive aspects of the strong force, which governs quarks inside protons and neutrons, on 5 October three American physicists were awarded the 2004 Nobel Prize in Physics. David J. Gross (Kavli Institute of Theoretical Physics, University of California, Santa Barbara), H. David Politzer (California Institute of Technology), and Frank Wilczek (Massachusetts Institute of Technology) made a key theoretical discovery with a surprising result: the closer quarks are together, the weaker the force - opposite to what is seen with electromagnetism and gravity. Rather, the strong force is analogous to a rubber band stretching, where the force increases as the quarks get farther apart. These physicists discovered this property of quarks, known as asymptotic freedom, in 1976. It later became a key part of the theory of quantum chromodynamics (QCD) and the Standard Model, the current best theory to describe the interac...

  17. Hepatobiliary fascioliasis in non-endemic zones: a surprise diagnosis.

    Science.gov (United States)

    Jha, Ashish Kumar; Goenka, Mahesh Kumar; Goenka, Usha; Chakrabarti, Amrita

    2013-03-01

    Fascioliasis is a zoonotic infection caused by Fasciola hepatica. Because of population migration and international food trade, human fascioliasis is being an increasingly recognised entity in nonendemic zones. In most parts of Asia, hepatobiliary fascioliasis is sporadic. Human hepatobiliary infection by this trematode has two distinct phases: an acute hepatic phase and a chronic biliary phase. Hepatobiliary infection is mostly associated with intense peripheral eosinophilia. In addition to classically defined hepatic phase and biliary phase fascioliasis, some cases may have an overlap of these two phases. Chronic liver abscess formation is a rare presentation. We describe a surprise case of hepatobiliary fascioliasis who presented to us with liver abscess without intense peripheral eosinophilia, a rare presentation of human fascioliasis especially in non-endemic zones. Copyright © 2013 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

  18. Postulated weather modification effects of large energy releases

    Energy Technology Data Exchange (ETDEWEB)

    Ramsdell, J.V.; Scott, B.C.; Orgill, M.M.; Renne, D.S.; Hubbard, J.E.; McGinnis, K.A.

    1977-02-01

    Postulated impacts of large energy releases were examined in the light of existing technical information. The magnitudes of direct atmospheric modifications were estimated, and the ecological and economic implications of the modifications were explored. Energy releases from energy centers (10 to 40 power plants at a single site) and individual power plant clusters (1 to 4 power plants) were considered. In the atmosphere the energy will exist initially as increased temperature (sensible heat), moisture (latent heat), and air motion (kinetic energy). Addition of energy could result in increased cloudiness and fog, and changed precipitation patterns. A framework for economic analysis of the impacts of the postulated atmospheric modifications was established on the basis of costs and benefits. Willingness-to-pay was selected as the appropriate measure for valuing each impact. The primary and secondary atmospheric modifications may affect recreation, transportation, and aesthetics as well as agriculture and forestry. Economic values can be placed on some of the effects. However, the willingness of people to pay to gain benefits and avoid damages in many cases can only be determined through extensive surveys. The economic consequences of a given energy release would be highly site specific.

  19. Postulated weather modification effects of large energy releases

    International Nuclear Information System (INIS)

    Ramsdell, J.V.; Scott, B.C.; Orgill, M.M.; Renne, D.S.; Hubbard, J.E.; McGinnis, K.A.

    1977-02-01

    Postulated impacts of large energy releases were examined in the light of existing technical information. The magnitudes of direct atmospheric modifications were estimated, and the ecological and economic implications of the modifications were explored. Energy releases from energy centers (10 to 40 power plants at a single site) and individual power plant clusters (1 to 4 power plants) were considered. In the atmosphere the energy will exist initially as increased temperature (sensible heat), moisture (latent heat), and air motion (kinetic energy). Addition of energy could result in increased cloudiness and fog, and changed precipitation patterns. A framework for economic analysis of the impacts of the postulated atmospheric modifications was established on the basis of costs and benefits. Willingness-to-pay was selected as the appropriate measure for valuing each impact. The primary and secondary atmospheric modifications may affect recreation, transportation, and aesthetics as well as agriculture and forestry. Economic values can be placed on some of the effects. However, the willingness of people to pay to gain benefits and avoid damages in many cases can only be determined through extensive surveys. The economic consequences of a given energy release would be highly site specific

  20. Large magnetocaloric effect of GdNiAl2 compound

    International Nuclear Information System (INIS)

    Dembele, S.N.; Ma, Z.; Shang, Y.F.; Fu, H.; Balfour, E.A.; Hadimani, R.L.; Jiles, D.C.; Teng, B.H.; Luo, Y.

    2015-01-01

    This paper presents the structure, magnetic properties, and magnetocaloric effect of the polycrystalline compound GdNiAl 2 . Powder X-ray diffraction (XRD) measurement and Rietveld refinement revealed that GdNiAl 2 alloy is CuMgAl 2 -type phase structure with about 1 wt% GdNi 2 Al 3 secondary phase. Magnetic measurements suggest that the compound is ferromagnetic and undergoes a second-order phase transition near 28 K. The maximum value of magnetic entropy change reaches 16.0 J/kg K for an applied magnetic field change of 0–50 kOe and the relative cooling power was 6.4×10 2 J/kg. It is a promising candidate as a magnetocaloric material working near liquid hydrogen temperature (~20 K) exhibiting large relative cooling power. - Highlights: • Preferred orientation with axis of [010] was found in the GdNiAl 2 compound. • The ΔS Mmax and the RCP are 16.0 J/kg K and 640 J/kg, respectively, for ΔH=50 kOe. • Relative low rare earth content in GdNiAl 2 comparing with other candidates

  1. X-rays from comets - a surprising discovery

    CERN Document Server

    CERN. Geneva

    2000-01-01

    Comets are kilometre-size aggregates of ice and dust, which remained from the formation of the solar system. It was not obvious to expect X-ray emission from such objects. Nevertheless, when comet Hyakutake (C/1996 B2) was observed with the ROSAT X-ray satellite during its close approach to Earth in March 1996, bright X-ray emission from this comet was discovered. This finding triggered a search in archival ROSAT data for comets, which might have accidentally crossed the field of view during observations of unrelated targets. To increase the surprise even more, X-ray emission was detected from four additional comets, which were optically 300 to 30 000 times fainter than Hyakutake. For one of them, comet Arai (C/1991 A2), X-ray emission was even found in data which were taken six weeks before the comet was optically discovered. These findings showed that comets represent a new class of celestial X-ray sources. The subsequent detection of X-ray emission from several other comets in dedicated observations confir...

  2. Effects of large-scale deforestation on precipitation in the monsoon regions: remote versus local effects.

    Science.gov (United States)

    Devaraju, N; Bala, Govindasamy; Modak, Angshuman

    2015-03-17

    In this paper, using idealized climate model simulations, we investigate the biogeophysical effects of large-scale deforestation on monsoon regions. We find that the remote forcing from large-scale deforestation in the northern middle and high latitudes shifts the Intertropical Convergence Zone southward. This results in a significant decrease in precipitation in the Northern Hemisphere monsoon regions (East Asia, North America, North Africa, and South Asia) and moderate precipitation increases in the Southern Hemisphere monsoon regions (South Africa, South America, and Australia). The magnitude of the monsoonal precipitation changes depends on the location of deforestation, with remote effects showing a larger influence than local effects. The South Asian Monsoon region is affected the most, with 18% decline in precipitation over India. Our results indicate that any comprehensive assessment of afforestation/reforestation as climate change mitigation strategies should carefully evaluate the remote effects on monsoonal precipitation alongside the large local impacts on temperatures.

  3. Self-organizing weights for Internet AS-graphs and surprisingly simple routing metrics

    DEFF Research Database (Denmark)

    Scholz, Jan Carsten; Greiner, Martin

    2011-01-01

    The transport capacity of Internet-like communication networks and hence their efficiency may be improved by a factor of 5–10 through the use of highly optimized routing metrics, as demonstrated previously. The numerical determination of such routing metrics can be computationally demanding...... to an extent that prohibits both investigation of and application to very large networks. In an attempt to find a numerically less expensive way of constructing a metric with a comparable performance increase, we propose a local, self-organizing iteration scheme and find two surprisingly simple and efficient...... metrics. The new metrics have negligible computational cost and result in an approximately 5-fold performance increase, providing distinguished competitiveness with the computationally costly counterparts. They are applicable to very large networks and easy to implement in today's Internet routing...

  4. Some remarks about large p/sub perpendicular/ spin effects

    International Nuclear Information System (INIS)

    Field, R.D.

    1977-01-01

    A discussion of the ingredients necessary to make predictions concerning single and double spin measurements in large p/sub perpendicular to/ inclusive processes is presented. Remarks are made as to what might be expected and what might be learned from such measurements. Various models for the production of large p/sub perpendicular to/ mesons have quite different spin structure and hence can be expected to give differing predictions. However, it is not possible at this time to make quantitative calculations, and it is possible (not probable) that the interesting spin observables will be negligibly small

  5. The influence of the surprising decay properties of element 108 on search experiments for new elements

    International Nuclear Information System (INIS)

    Hofmann, S.; Armbruster, P.; Muenzenberg, G.; Reisdorf, W.; Schmidt, K.H.; Burkhard, H.G.; Hessberger, F.P.; Schoett, H.J.; Agarwal, Y.K.; Berthes, G.; Gollerthan, U.; Folger, H.; Hingmann, J.G.; Keller, J.G.; Leino, M.E.; Lemmertz, P.; Montoya, M.; Poppensieker, K.; Quint, B.; Zychor, I.

    1986-01-01

    Results of experiments to synthesize the heaviest elements are reported. Surprising is the high stability against fission not only of the odd and odd-odd nuclei but also of even isotopes of even elements. Alpha decay data gave an increasing stability of nuclei by shell effects up to 266 109, the heaviest known element. Theoretically, the high stability is explained by an island of nuclei with big quadrupole and hexadecapole deformations around Z=109 and N=162. Future experiments will be planned to prove the island character of these heavy nuclei. (orig.)

  6. Beyond surprise : A longitudinal study on the experience of visual-tactual incongruities in products

    NARCIS (Netherlands)

    Ludden, G.D.S.; Schifferstein, H.N.J.; Hekkert, P.

    2012-01-01

    When people encounter products with visual-tactual incongruities, they are likely to be surprised because the product feels different than expected. In this paper, we investigate (1) the relationship between surprise and the overall liking of the products, (2) the emotions associated with surprise,

  7. Surprising Incentive: An Instrument for Promoting Safety Performance of Construction Employees

    Directory of Open Access Journals (Sweden)

    Fakhradin Ghasemi

    2015-09-01

    Conclusion: The results of this study proved that the surprising incentive would improve the employees' safety performance just in the short term because the surprising value of the incentives dwindle over time. For this reason and to maintain the surprising value of the incentive system, the amount and types of incentives need to be evaluated and modified annually or biannually.

  8. The Role of Surprise in Game-Based Learning for Mathematics

    NARCIS (Netherlands)

    Wouters, Pieter; van Oostendorp, Herre; ter Vrugte, Judith; Vandercruysse, Sylke; de Jong, Anthonius J.M.; Elen, Jan; De Gloria, Alessandro; Veltkamp, Remco

    2016-01-01

    In this paper we investigate the potential of surprise on learning with prevocational students in the domain of proportional reasoning. Surprise involves an emotional reaction, but it also serves a cognitive goal as it directs attention to explain why the surprising event occurred and to learn for

  9. Effects of Turbine Spacings in Very Large Wind Farms

    DEFF Research Database (Denmark)

    farm. LES simulations of large wind farms are performed with full aero-elastic Actuator Lines. The simulations investigate the inherent dynamics inside wind farms in the absence of atmospheric turbulence compared to cases with atmospheric turbulence. Resulting low frequency structures are inherent...... in wind farms for certain turbine spacings and affect both power production and loads...

  10. The Large-scale Effect of Environment on Galactic Conformity

    Science.gov (United States)

    Sun, Shuangpeng; Guo, Qi; Wang, Lan; Wang, Jie; Gao, Liang; Lacey, Cedric G.; Pan, Jun

    2018-04-01

    We use a volume-limited galaxy sample from the SDSS Data Release 7 to explore the dependence of galactic conformity on the large-scale environment, measured on ˜ 4 Mpc scales. We find that the star formation activity of neighbour galaxies depends more strongly on the environment than on the activity of their primary galaxies. In under-dense regions most neighbour galaxies tend to be active, while in over-dense regions neighbour galaxies are mostly passive, regardless of the activity of their primary galaxies. At a given stellar mass, passive primary galaxies reside in higher density regions than active primary galaxies, leading to the apparently strong conformity signal. The dependence of the activity of neighbour galaxies on environment can be explained by the corresponding dependence of the fraction of satellite galaxies. Similar results are found for galaxies in a semi-analytical model, suggesting that no new physics is required to explain the observed large-scale conformity.

  11. Estimating population effects of vaccination using large, routinely collected data.

    Science.gov (United States)

    Halloran, M Elizabeth; Hudgens, Michael G

    2018-01-30

    Vaccination in populations can have several kinds of effects. Establishing that vaccination produces population-level effects beyond the direct effects in the vaccinated individuals can have important consequences for public health policy. Formal methods have been developed for study designs and analysis that can estimate the different effects of vaccination. However, implementing field studies to evaluate the different effects of vaccination can be expensive, of limited generalizability, or unethical. It would be advantageous to use routinely collected data to estimate the different effects of vaccination. We consider how different types of data are needed to estimate different effects of vaccination. The examples include rotavirus vaccination of young children, influenza vaccination of elderly adults, and a targeted influenza vaccination campaign in schools. Directions for future research are discussed. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Effect of large dose gamma-ray irradiation on polyimide

    International Nuclear Information System (INIS)

    Morita, Yohsuke; Watanabe, Kiyoshi; Yagyu, Hideki.

    1988-01-01

    In the radiation environment of atomic energy, space and so on, with the heightening of the performance of equipment, the organic materials having the radiation resistance up to several hundreds MGy have been demanded. Polyimide is one of a small number of the polymers which are considered to be applicable to such environment. However, actually the characteristics as the insulator for such large dose radiation environment have not been sufficiently verified. In this study, the gamma-ray of as large dose as 100 MGy was irradiated on the polyimides having different chemical structure in the air and in nitrogen, and the change of their mechanical and electrical characteristics was elucidated, at the same time, the structural change was examined. The four kinds of polyimides used for the experiment were three kinds of thermosetting type and thermoplastic polyether imide. Co-60 gamma-ray was irradiated at the dose rate of 17 kGy/h at room temperature. The tensile properties, volume resistivity, dielectric tangent, gel fraction, glass transition temperature and IR spectra were examined. In the air, the characteristics lowered by large dose irradiation due to the severance of main chains. In nitrogen, the deterioration was extremely slight, and cross-linking occurred. (K.I.)

  13. The Effect of Large Scale Salinity Gradient on Langmuir Turbulence

    Science.gov (United States)

    Fan, Y.; Jarosz, E.; Yu, Z.; Jensen, T.; Sullivan, P. P.; Liang, J.

    2017-12-01

    Langmuir circulation (LC) is believed to be one of the leading order causes of turbulent mixing in the upper ocean. It is important for momentum and heat exchange across the mixed layer (ML) and directly impact the dynamics and thermodynamics in the upper ocean and lower atmosphere including the vertical distributions of chemical, biological, optical, and acoustic properties. Based on Craik and Leibovich (1976) theory, large eddy simulation (LES) models have been developed to simulate LC in the upper ocean, yielding new insights that could not be obtained from field observations and turbulent closure models. Due its high computational cost, LES models are usually limited to small domain sizes and cannot resolve large-scale flows. Furthermore, most LES models used in the LC simulations use periodic boundary conditions in the horizontal direction, which assumes the physical properties (i.e. temperature and salinity) and expected flow patterns in the area of interest are of a periodically repeating nature so that the limited small LES domain is representative for the larger area. Using periodic boundary condition can significantly reduce computational effort in problems, and it is a good assumption for isotropic shear turbulence. However, LC is anisotropic (McWilliams et al 1997) and was observed to be modulated by crosswind tidal currents (Kukulka et al 2011). Using symmetrical domains, idealized LES studies also indicate LC could interact with oceanic fronts (Hamlington et al 2014) and standing internal waves (Chini and Leibovich, 2005). The present study expands our previous LES modeling investigations of Langmuir turbulence to the real ocean conditions with large scale environmental motion that features fresh water inflow into the study region. Large scale gradient forcing is introduced to the NCAR LES model through scale separation analysis. The model is applied to a field observation in the Gulf of Mexico in July, 2016 when the measurement site was impacted by

  14. An effective filter for IBD detection in large data sets.

    KAUST Repository

    Huang, Lin

    2014-03-25

    Identity by descent (IBD) inference is the task of computationally detecting genomic segments that are shared between individuals by means of common familial descent. Accurate IBD detection plays an important role in various genomic studies, ranging from mapping disease genes to exploring ancient population histories. The majority of recent work in the field has focused on improving the accuracy of inference, targeting shorter genomic segments that originate from a more ancient common ancestor. The accuracy of these methods, however, is achieved at the expense of high computational cost, resulting in a prohibitively long running time when applied to large cohorts. To enable the study of large cohorts, we introduce SpeeDB, a method that facilitates fast IBD detection in large unphased genotype data sets. Given a target individual and a database of individuals that potentially share IBD segments with the target, SpeeDB applies an efficient opposite-homozygous filter, which excludes chromosomal segments from the database that are highly unlikely to be IBD with the corresponding segments from the target individual. The remaining segments can then be evaluated by any IBD detection method of choice. When examining simulated individuals sharing 4 cM IBD regions, SpeeDB filtered out 99.5% of genomic regions from consideration while retaining 99% of the true IBD segments. Applying the SpeeDB filter prior to detecting IBD in simulated fourth cousins resulted in an overall running time that was 10,000x faster than inferring IBD without the filter and retained 99% of the true IBD segments in the output.

  15. An effective filter for IBD detection in large data sets.

    KAUST Repository

    Huang, Lin; Bercovici, Sivan; Rodriguez, Jesse M; Batzoglou, Serafim

    2014-01-01

    Identity by descent (IBD) inference is the task of computationally detecting genomic segments that are shared between individuals by means of common familial descent. Accurate IBD detection plays an important role in various genomic studies, ranging from mapping disease genes to exploring ancient population histories. The majority of recent work in the field has focused on improving the accuracy of inference, targeting shorter genomic segments that originate from a more ancient common ancestor. The accuracy of these methods, however, is achieved at the expense of high computational cost, resulting in a prohibitively long running time when applied to large cohorts. To enable the study of large cohorts, we introduce SpeeDB, a method that facilitates fast IBD detection in large unphased genotype data sets. Given a target individual and a database of individuals that potentially share IBD segments with the target, SpeeDB applies an efficient opposite-homozygous filter, which excludes chromosomal segments from the database that are highly unlikely to be IBD with the corresponding segments from the target individual. The remaining segments can then be evaluated by any IBD detection method of choice. When examining simulated individuals sharing 4 cM IBD regions, SpeeDB filtered out 99.5% of genomic regions from consideration while retaining 99% of the true IBD segments. Applying the SpeeDB filter prior to detecting IBD in simulated fourth cousins resulted in an overall running time that was 10,000x faster than inferring IBD without the filter and retained 99% of the true IBD segments in the output.

  16. Systematic renormalization of the effective theory of Large Scale Structure

    International Nuclear Information System (INIS)

    Abolhasani, Ali Akbar; Mirbabayi, Mehrdad; Pajer, Enrico

    2016-01-01

    A perturbative description of Large Scale Structure is a cornerstone of our understanding of the observed distribution of matter in the universe. Renormalization is an essential and defining step to make this description physical and predictive. Here we introduce a systematic renormalization procedure, which neatly associates counterterms to the UV-sensitive diagrams order by order, as it is commonly done in quantum field theory. As a concrete example, we renormalize the one-loop power spectrum and bispectrum of both density and velocity. In addition, we present a series of results that are valid to all orders in perturbation theory. First, we show that while systematic renormalization requires temporally non-local counterterms, in practice one can use an equivalent basis made of local operators. We give an explicit prescription to generate all counterterms allowed by the symmetries. Second, we present a formal proof of the well-known general argument that the contribution of short distance perturbations to large scale density contrast δ and momentum density π(k) scale as k 2 and k, respectively. Third, we demonstrate that the common practice of introducing counterterms only in the Euler equation when one is interested in correlators of δ is indeed valid to all orders.

  17. Graviton collider effects in one and more large extra dimensions

    International Nuclear Information System (INIS)

    Giudice, Gian F.; Plehn, Tilman; Strumia, Alessandro

    2005-01-01

    Astrophysical bounds severely limit the possibility of observing collider signals of gravity with less than 3 flat extra dimensions. However, small distortions of the compactified space can lift the masses of the lightest graviton excitations, evading astrophysical bounds without affecting collider signals of quantum gravity. Following this procedure we reconsider theories with one large extra dimension. A slight space warping gives a model which is safe in the infrared against astrophysical and observational bounds, and which has the ultraviolet properties of gravity with a single flat extra dimension. We extend collider studies to the case of one extra dimension, pointing out its peculiarities. Finally, for a generic number of extra dimensions, we compare different channels in LHC searches for quantum gravity, introducing an ultraviolet cutoff as an additional parameter besides the Planck mass

  18. Analyses of hydrodynamic effects of large sodium-water reactions

    International Nuclear Information System (INIS)

    Sakano, K.; Shindo, Y.; Koishikawa, A.; Maekawa, I.

    1977-01-01

    Large leak sodium-water reactions that would occur in a steam generator of LMFBR causes abrupt changes of pressure and velocity of fluid in a secondary sodium system and relief system. This paper describes SOWACS-III together with its model and method. Results of analyses are also given, the comparison with experimental results of initial pressure spike being included. SOWACS-III treats the system which consists of the steam generator, vessel, valve, pump and pipe, and uses the following models and methods. (1) Components are assumed to be one-dimensional. (2) Pressure wave propagation near a reaction zone, where hydrogen is generated, is analyzed with the spherical co-ordinate (sphere-cylinder model). (3) A moving boundary is formed by contact of sodium with other fluid such as hydrogen and nitrogen. The boundary travels without mixing of sodium and another fluid through the boundary (boundary tracking model). The boundary can be treated not to move from the original place (fixed boundary model). (4) Pressure wave propagation is analyzed by the explicit method of characteristics in one-dimensional Eulerian co-ordinate. (5) Flow-induced force is analyzed by momentum balance. (6) The lateral motion of relief piping caused by the force is analyzed by NASTRAN code. Analyses were carried out for large sodium-water reaction experiments in SWAT-3 rig of PNC by using the sphere-cylinder model. The calculated pressure spike in the reaction vessel was compared with the measured one for a few milliseconds after water injection. The calculated value and measured one were 6.4 ata and 6.7 ata for peak pressure and 0.6 ms and 2.8 ms for rising time, respectively

  19. 'Surprise': Outbreak of Campylobacter infection associated with chicken liver pâté at a surprise birthday party, Adelaide, Australia, 2012.

    Science.gov (United States)

    Parry, Amy; Fearnley, Emily; Denehy, Emma

    2012-10-01

    In July 2012, an outbreak of Campylobacter infection was investigated by the South Australian Communicable Disease Control Branch and Food Policy and Programs Branch. The initial notification identified illness at a surprise birthday party held at a restaurant on 14 July 2012. The objective of the investigation was to identify the potential source of infection and institute appropriate intervention strategies to prevent further illness. A guest list was obtained and a retrospective cohort study undertaken. A combination of paper-based and telephone questionnaires were used to collect exposure and outcome information. An environmental investigation was conducted by Food Policy and Programs Branch at the implicated premises. All 57 guests completed the questionnaire (100% response rate), and 15 met the case definition. Analysis showed a significant association between illness and consumption of chicken liver pâté (relative risk: 16.7, 95% confidence interval: 2.4-118.6). No other food or beverage served at the party was associated with illness. Three guests submitted stool samples; all were positive for Campylobacter. The environmental investigation identified that the cooking process used in the preparation of chicken liver pâté may have been inconsistent, resulting in some portions not cooked adequately to inactivate potential Campylobacter contamination. Chicken liver products are a known source of Campylobacter infection; therefore, education of food handlers remains a high priority. To better identify outbreaks among the large number of Campylobacter notifications, routine typing of Campylobacter isolates is recommended.

  20. Are seismic hazard assessment errors and earthquake surprises unavoidable?

    Science.gov (United States)

    Kossobokov, Vladimir

    2013-04-01

    Why earthquake occurrences bring us so many surprises? The answer seems evident if we review the relationships that are commonly used to assess seismic hazard. The time-span of physically reliable Seismic History is yet a small portion of a rupture recurrence cycle at an earthquake-prone site, which makes premature any kind of reliable probabilistic statements about narrowly localized seismic hazard. Moreover, seismic evidences accumulated to-date demonstrate clearly that most of the empirical relations commonly accepted in the early history of instrumental seismology can be proved erroneous when testing statistical significance is applied. Seismic events, including mega-earthquakes, cluster displaying behaviors that are far from independent or periodic. Their distribution in space is possibly fractal, definitely, far from uniform even in a single segment of a fault zone. Such a situation contradicts generally accepted assumptions used for analytically tractable or computer simulations and complicates design of reliable methodologies for realistic earthquake hazard assessment, as well as search and definition of precursory behaviors to be used for forecast/prediction purposes. As a result, the conclusions drawn from such simulations and analyses can MISLEAD TO SCIENTIFICALLY GROUNDLESS APPLICATION, which is unwise and extremely dangerous in assessing expected societal risks and losses. For example, a systematic comparison of the GSHAP peak ground acceleration estimates with those related to actual strong earthquakes, unfortunately, discloses gross inadequacy of this "probabilistic" product, which appears UNACCEPTABLE FOR ANY KIND OF RESPONSIBLE SEISMIC RISK EVALUATION AND KNOWLEDGEABLE DISASTER PREVENTION. The self-evident shortcomings and failures of GSHAP appeals to all earthquake scientists and engineers for an urgent revision of the global seismic hazard maps from the first principles including background methodologies involved, such that there becomes: (a) a

  1. Segmentation, Diarization and Speech Transcription: Surprise Data Unraveled

    NARCIS (Netherlands)

    Huijbregts, M.A.H.

    2008-01-01

    In this thesis, research on large vocabulary continuous speech recognition for unknown audio conditions is presented. For automatic speech recognition systems based on statistical methods, it is important that the conditions of the audio used for training the statistical models match the conditions

  2. Short-range effects in large white dwarfs

    International Nuclear Information System (INIS)

    Membrado, M.C.; Pacheco, A.F.

    1988-01-01

    Recent work of Membrado and Pacheco (1988) on the implication of Yukawa-like effects in small white dwarfs is extended to analyze the very massive case. Although the role of these impurities grows substantially as the radius of the star decreases, when reasonable supergravity parameters are used the predicted change in the white dwarf mass-radius relation is unobservably small. 8 references

  3. Effective horizons, junction conditions and large-scale magnetism

    Energy Technology Data Exchange (ETDEWEB)

    Giovannini, Massimo [CERN, Department of Physics, Theory Division, Geneva (Switzerland); INFN, Milan (Italy)

    2017-08-15

    The quantum mechanical generation of hypermagnetic and hyperelectric fields in four-dimensional conformally flat background geometries rests on the simultaneous continuity of the effective horizon and of the extrinsic curvature across the inflationary boundary. The junction conditions for the gauge fields are derived in general terms and corroborated by explicit examples with particular attention to the limit of a sudden (but nonetheless continuous) transition of the effective horizon. After reducing the dynamics to a pair of integral equations related by duality transformations, we compute the power spectra and deduce a novel class of logarithmic corrections which turn out to be, however, numerically insignificant and overwhelmed by the conductivity effects once the gauge modes reenter the effective horizon. In this perspective the magnetogenesis requirements and the role of the postinflationary conductivity are clarified and reappraised. As long as the total duration of the inflationary phase is nearly minimal, quasi-flat hypermagnetic power spectra are comparatively more common than in the case of vacuum initial data. (orig.)

  4. Effect Of Exogenous Progesterone On Blood Chemistry Of Large ...

    African Journals Online (AJOL)

    Exogenous hormones are major economic factors in swine production. This study evaluate the effects of exogenous administration of progesterone on the blood chemistry of pigs.Experiment involved weekly injections of progesterone to 24 pigs (12 males and 12 females)from day old to 24 weeks and only corn oil to another ...

  5. Large strengthening effect of a hip-flexor training programme

    DEFF Research Database (Denmark)

    Thorborg, Kristian; Bandholm, Thomas Quaade; Zebis, Mette

    2016-01-01

    PURPOSE: To investigate the effect on hip-flexion strength of a 6-week hip-flexor training programme using elastic bands as resistance. We hypothesized that the training group, compared to a control group, would increase their hip-flexion strength more. METHODS: Thirty-three healthy subjects (45 ...

  6. Effectiveness of hearing conservation program at a large surface ...

    African Journals Online (AJOL)

    A study conducted to determine the effectiveness of a Hearing Conservation Programme (HcP) was conducted in a surface gold mining Company in Ghana. The procedure adopted included a retrospective review and comparison of individual Audiograms from 1999-2003. The analysis of data was based on 200 workers at ...

  7. Effectiveness of hearing conservation program at a large surface ...

    African Journals Online (AJOL)

    kemrilib

    African Journal of Health Sciences, Volume 14, Numbers 1-2, January-June 2007. 49. Effectiveness ... Programme (HcP) was conducted in a surface gold mining Company in Ghana. The ... The analysis of data was based on 200 workers at ..... Industry. New York Raven Press 1982. 9. Franks JR, Davis RR and Kreig EF jr.

  8. Longitudinal intensity effects in the CERN Large Hadron Collider

    CERN Document Server

    AUTHOR|(CDS)2081238; Rivkin, Leonid

    This PhD thesis provides an improved knowledge of the LHC longitudinal impedance model and a better understanding of the longitudinal intensity effects. These effects can limit the LHC performance and lead to a reduction of the integrated luminosity. The LHC longitudinal impedance was measured with beams. Results obtained using traditional techniques are consistent with the expectations based on the impedance model, although the measurement precision was proven insufficient for the low impedance of the LHC. Innovative methods to probe the LHC reactive impedance were successfully used. One of the methods is based on exciting the beam with a sinusoidal rf phase modulation to estimate the synchrotron frequency shift from potential-well distortion. In the second method, the impedance is estimated from the loss of Landau damping threshold, which is also found to be in good agreement with analytical estimations. Beam-based impedance measurements agree well with estimations using the LHC impedance model. Macropartic...

  9. Mitigating Surprise Through Enhanced Operational Design: Civilian Conceptual Planning Models

    Science.gov (United States)

    2007-01-01

    political, historical, cultural , and economic contexts. If we are going to fight among the people, we must understand them.1 When evaluating US military...represents both the Christian and Yoruba minorities as well as the military, continues to compete against rival elites representing disparate elements...undeniably have to learn a new culture , the physical battlespace would not be alien since MS-13 maintains a large presence in areas that are home to

  10. Analytic expressions for polarimetry in plasma with large Cotton endash Mouton or Faraday effects

    International Nuclear Information System (INIS)

    Segre, S.E.

    1996-01-01

    Analytic expressions for plasma polarimetry are derived for the case when either the Cotton endash Mouton effect or the Faraday effect is large while the other effect is small. copyright 1996 American Institute of Physics

  11. Some Fluid Dynamic Effects in Large-Scale MHD Generators

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, J. C.R. [University of Warwick, Coventry (United Kingdom)

    1966-10-15

    At the present time we are unable to carry out a complete analysis of the fluid dynamics and electrodynamics of an MHD generator. However, various aspects of the behaviour of an MHD generator may be examined by the use of simplified models, for example: (1) one-dimensional gas dynamics (Louis et al. 1964); (2) the current distribution can be found if the velocity is assumed constant across the duct (Witalis, 1965); (3) the skin friction and heat transfer to the walls can be calculated by boundary layer analysis if the flow is assumed to be laminar (Kerrebrock, 1961), and (4) a complete description of the velocity and current distribution across the duct can be given if the flow is assumed to be uniform, laminar, incompressible and not varying in the flow direction (Hunt and Stewartson, 1965). Taken together, these and other models will enable us to describe most of the effects in an MHD generator. In this paper another simplification is considered in which the electromagnetic forces are assumed to be much larger than the inertial forces. The ratio of these two forces is measured by the parameter, S = aB{sup 2}{sub 0}d/pU, where o is the conductivity, B{sub 0} the magnetic field, d the width of the duct, p the density and U the mean velocity. Thus S >> 1. We also assume that the magnetic Reynolds number is very much less than one. In the largest experimental generators now being built S {approx} 2 . Thus, though the results of this model are not immediately applicable, they should indicate the effects of increasing the magnetic field strength and the size of MHD generators. When S >> 1, one can can consider the duct to be divided into 2 regions: (1) a core region where electromagnetic forces are balanced by the pressure gradient and where inertial as well as viscous forces are negligible, and (2) boundary layers on the walls where again inertial forces are negligible but where the viscous, electromagnetic and pressure forces are of the same order. We show how it is

  12. Large-scale climatic effects on traditional Hawaiian fishpond aquaculture.

    Directory of Open Access Journals (Sweden)

    Daniel McCoy

    Full Text Available Aquaculture accounts for almost one-half of global fish consumption. Understanding the regional impact of climate fluctuations on aquaculture production thus is critical for the sustainability of this crucial food resource. The objective of this work was to understand the role of climate fluctuations and climate change in subtropical coastal estuarine environments within the context of aquaculture practices in He'eia Fishpond, O'ahu Island, Hawai'i. To the best of our knowledge, this was the first study of climate effects on traditional aquaculture systems in the Hawaiian Islands. Data from adjacent weather stations were analyzed together with in situ water quality instrument deployments spanning a 12-year period (November 2004 -November 2016. We found correlations between two periods with extremely high fish mortality at He'eia Fishpond (May and October 2009 and slackening trade winds in the week preceding each mortality event, as well as surface water temperatures elevated 2-3°C higher than the background periods (March-December 2009. We posit that the lack of trade wind-driven surface water mixing enhanced surface heating and stratification of the water column, leading to hypoxic conditions and stress on fish populations, which had limited ability to move within net pen enclosures. Elevated water temperature and interruption of trade winds previously have been linked to the onset of El Niño in Hawai'i. Our results provide empirical evidence regarding El Niño effects on the coastal ocean, which can inform resource management efforts about potential impact of climate variation on aquaculture production. Finally, we provide recommendations for reducing the impact of warming events on fishponds, as these events are predicted to increase in magnitude and frequency as a consequence of global warming.

  13. Atmospheric effects of heat release at large power plants

    International Nuclear Information System (INIS)

    Kikuchi, Yukio

    1979-01-01

    In power plants, the thermal efficiency of generating electricity is generally 1/3, the rest 2/3 being carried away by cooling water. To release the heat, there are three alternative methods; i.e. cooling water released into sea, cooling water released into a cooling pond, and cooling of such water with a cooling tower. In the third method, cooling towers are stacks of 10m -- 80m bore, and warm cooling water flowing on the side wall is cooled with atmospheric air. The resultant heated air is discharged as plume from their top. Upon condensation, it becomes visible and then leads to the formation of clouds. In this manner, the weather around the sites of power plants is affected, such as reduction of insolation reaching ground and increase in precipitation. The following matters are described: cooling towers; phenomena and prediction methods of visible plume, cloud formation, increase of precipitation and deposition of drifting waterdrops; and effects of the group of power plants. (J.P.N.)

  14. Latin America: how a region surprised the experts.

    Science.gov (United States)

    De Sherbinin, A

    1993-02-01

    In 1960-1970, family planning specialists and demographers worried that poverty, limited education, Latin machismo, and strong catholic ideals would obstruct family planning efforts to reduce high fertility in Latin America. It had the highest annual population growth rate in the world (2.8%), which would increase the population 2-fold in 25 years. Yet, the UN's 1992 population projection for Latin America and the Caribbean in the year 2000 was about 20% lower than its 1963 projection (just over 500 vs. 638 million). Since life expectancy increased simultaneously from 57 to 68 years, this reduced projection was caused directly by a large decline in fertility from 5.9 to 3. A regression analysis of 11 Latin American and Caribbean countries revealed that differences in the contraceptive prevalence rates accounted for 90% of the variation in the total fertility rate between countries. Thus, contraception played a key role in the fertility decline. The second most significant determinant of fertility decline was an increase in the average age at first marriage from about 20 to 23 years. Induced abortion and breast feeding did not contribute significantly to fertility decline. The major socioeconomic factors responsible for the decline included economic development and urbanization, resulting in improvements in health care, reduced infant and child mortality, and increases in female literacy, education, and labor force participation. Public and private family planning programs also contributed significantly to the decline. They expanded from cities to remote rural areas, thereby increasing access to contraception. By the early 1990s, Brazil, Mexico, and Colombia had among the lowest levels of unmet need (13-24%) in developing countries. Other key factors of fertility decline were political commitment, strong communication efforts, and stress on quality services. Latin America provides hope to other regions where religion and culture promote a large family size.

  15. Automated Atmospheric Composition Dataset Level Metadata Discovery. Difficulties and Surprises

    Science.gov (United States)

    Strub, R. F.; Falke, S. R.; Kempler, S.; Fialkowski, E.; Goussev, O.; Lynnes, C.

    2015-12-01

    The Atmospheric Composition Portal (ACP) is an aggregator and curator of information related to remotely sensed atmospheric composition data and analysis. It uses existing tools and technologies and, where needed, enhances those capabilities to provide interoperable access, tools, and contextual guidance for scientists and value-adding organizations using remotely sensed atmospheric composition data. The initial focus is on Essential Climate Variables identified by the Global Climate Observing System - CH4, CO, CO2, NO2, O3, SO2 and aerosols. This poster addresses our efforts in building the ACP Data Table, an interface to help discover and understand remotely sensed data that are related to atmospheric composition science and applications. We harvested GCMD, CWIC, GEOSS metadata catalogs using machine to machine technologies - OpenSearch, Web Services. We also manually investigated the plethora of CEOS data providers portals and other catalogs where that data might be aggregated. This poster is our experience of the excellence, variety, and challenges we encountered.Conclusions:1.The significant benefits that the major catalogs provide are their machine to machine tools like OpenSearch and Web Services rather than any GUI usability improvements due to the large amount of data in their catalog.2.There is a trend at the large catalogs towards simulating small data provider portals through advanced services. 3.Populating metadata catalogs using ISO19115 is too complex for users to do in a consistent way, difficult to parse visually or with XML libraries, and too complex for Java XML binders like CASTOR.4.The ability to search for Ids first and then for data (GCMD and ECHO) is better for machine to machine operations rather than the timeouts experienced when returning the entire metadata entry at once. 5.Metadata harvest and export activities between the major catalogs has led to a significant amount of duplication. (This is currently being addressed) 6.Most (if not

  16. EFFECTS OF LARGE-SCALE POULTRY FARMS ON AQUATIC MICROBIAL COMMUNITIES: A MOLECULAR INVESTIGATION.

    Science.gov (United States)

    The effects of large-scale poultry production operations on water quality and human health are largely unknown. Poultry litter is frequently applied as fertilizer to agricultural lands adjacent to large poultry farms. Run-off from the land introduces a variety of stressors into t...

  17. Threats and surprises behind IPv6 extension headers

    NARCIS (Netherlands)

    Hendriks, Luuk; Velan, Petr; de Oliveira Schmidt, Ricardo; De Boer, Pieter Tjerk; Pras, Aiko

    2017-01-01

    The concept of Extension Headers, newly introduced with IPv6, is elusive and enables new types of threats in the Internet. Simply dropping all traffic containing any Extension Header - a current practice by operators-seemingly is an effective solution, but at the cost of possibly dropping legitimate

  18. Orbital melanocytoma: When a tumor becomes a relieving surprise

    Directory of Open Access Journals (Sweden)

    Haytham E. Nasr

    2018-06-01

    Full Text Available Purpose: Melanocytomas are rare pigmented tumors that arise form melanocytes and have been reported in the central nervous system. Orbital melanocytomas “also known as blue nevus” are rarely reported. The occurrence of choroidal melanoma and orbital melanocytomas has never been described. Observations: This is a case of orbital melanocytoma in a 34 year old female who presented with left proptosis and ecchymosis. She has the right eye enucleated to treat a large choroidal melanoma, 6 years earlier. Orbital metastasis was suspected. After orbital imaging and systemic evaluation, incisional biopsy was planned yet the mass could be totally excised and it turned out to be melanocytoma. The condition was not associated with nevus of Ota and the patient is not known to have any predisposing condition for melanocytic lesions. Conclusion and importance: Melanocytoma and malignant melanoma share the same cell of origin. The benign course, the well differentiated cells, absence of anaplasia and the positive reaction to Human Melanoma Black-45 (HMB-45 and S-100 proteins established the diagnosis of the former. Such diagnosis was a relief for this one eyed patient.(HMB-45:human melanoma black-45. Keywords: Orbit, Melanocytoma, Choroidal melanoma, HMB-45, S-100

  19. Ampullary Mixed Adenoneuroendocrine Carcinoma: Surprise Histology, Familiar Management.

    Science.gov (United States)

    Mahansaria, Shyam Sunder; Agrawal, Nikhil; Arora, Asit; Bihari, Chhagan; Appukuttan, Murali; Chattopadhyay, Tushar Kanti

    2017-10-01

    Mixed adenoneuroendocrine carcinoma (MANEC) has recently been defined by the World Health Organization in 2010. These are rare tumors and MANECs of ampullary region are even rarer. Only 19 cases have been reported in literature. We present 3 cases; the largest series, second case of amphicrine tumor and first case associated with chronic pancreatitis. Retrospective review of 3 patients who were diagnosed to have ampullary MANEC. All 3 patients were diagnosed preoperatively as neuroendocrine carcinoma and underwent margin negative pancreaticoduodenectomy. The histopathology revealed MANECs of small cell, mixed type in 2 patients and large cell, amphicrine type in 1 patient. The neuroendocrine component was grade 3 in all, the tumor was T3 in 2 and T2 in 1 and all had nodal metastases. Two patients received adjuvant chemotherapy and 2 of them had recurrence at 13 and 16 months. The median survival was 15 months. Ampullary MANECs are rare tumors. They are diagnosed on histopathologic examination of the resected specimen. Clinical presentation, management, and prognosis is similar to ampullary adenocarcinoma in literature.

  20. Aeolian comminution experiments revealing surprising sandball mineral aggregates

    Science.gov (United States)

    Nørnberg, P.; Bak, E.; Finster, K.; Gunnlaugsson, H. P.; Iversen, J. J.; Jensen, S. Knak; Merrison, J. P.

    2014-06-01

    We have undertaken a set of wind erosion experiments on a simple and well defined mineral, quartz. In these experiments wind action is simulated by end over end tumbling of quartz grains in a sealed quartz flask. The tumbling induces collisions among the quartz grains and the walls of the flask. This process simulates wind action impact speed of ∼1.2 m/s. After several months of tumbling we observed the formation of a large number of spherical sand aggregates, which resemble small snowballs under optical microscopy. Upon mechanical load the aggregates are seen to be more elastic than quartz and their mechanical strength is comparable, though slightly lower than that of sintered silica aerogels. Aggregates of this kind have not been reported from field sites or from closed circulation systems. However, sparse occurrence might explain this, or in nature the concentration of the aggregate building particles is so low that they never meet and just appear as the most fine grained tail of the sediment particle size distribution.

  1. Surprising structures hiding in Penrose’s future null infinity

    Science.gov (United States)

    Newman, Ezra T.

    2017-07-01

    Since the late1950s, almost all discussions of asymptotically flat (Einstein-Maxwell) space-times have taken place in the context of Penrose’s null infinity, I+. In addition, almost all calculations have used the Bondi coordinate and tetrad systems. Beginning with a known asymptotically flat solution to the Einstein-Maxwell equations, we show first, that there are other natural coordinate systems, near I+, (analogous to light-cones in flat-space) that are based on (asymptotically) shear-free null geodesic congruences (analogous to the flat-space case). Using these new coordinates and their associated tetrad, we define the complex dipole moment, (the mass dipole plus i times angular momentum), from the l  =  1 harmonic coefficient of a component of the asymptotic Weyl tensor. Second, from this definition, from the Bianchi identities and from the Bondi-Sachs mass and linear momentum, we show that there exists a large number of results—identifications and dynamics—identical to those of classical mechanics and electrodynamics. They include, among many others, {P}=M{v}+..., {L}= {r} × {P} , spin, Newton’s second law with the rocket force term (\\dotM v) and radiation reaction, angular momentum conservation and others. All these relations take place in the rather mysterious H-space rather than in space-time. This leads to the enigma: ‘why do these well known relations of classical mechanics take place in H-space?’ and ‘What is the physical meaning of H-space?’

  2. Distinct medial temporal networks encode surprise during motivation by reward versus punishment

    Science.gov (United States)

    Murty, Vishnu P.; LaBar, Kevin S.; Adcock, R. Alison

    2016-01-01

    Adaptive motivated behavior requires predictive internal representations of the environment, and surprising events are indications for encoding new representations of the environment. The medial temporal lobe memory system, including the hippocampus and surrounding cortex, encodes surprising events and is influenced by motivational state. Because behavior reflects the goals of an individual, we investigated whether motivational valence (i.e., pursuing rewards versus avoiding punishments) also impacts neural and mnemonic encoding of surprising events. During functional magnetic resonance imaging (fMRI), participants encountered perceptually unexpected events either during the pursuit of rewards or avoidance of punishments. Despite similar levels of motivation across groups, reward and punishment facilitated the processing of surprising events in different medial temporal lobe regions. Whereas during reward motivation, perceptual surprises enhanced activation in the hippocampus, during punishment motivation surprises instead enhanced activation in parahippocampal cortex. Further, we found that reward motivation facilitated hippocampal coupling with ventromedial PFC, whereas punishment motivation facilitated parahippocampal cortical coupling with orbitofrontal cortex. Behaviorally, post-scan testing revealed that reward, but not punishment, motivation resulted in greater memory selectivity for surprising events encountered during goal pursuit. Together these findings demonstrate that neuromodulatory systems engaged by anticipation of reward and punishment target separate components of the medial temporal lobe, modulating medial temporal lobe sensitivity and connectivity. Thus, reward and punishment motivation yield distinct neural contexts for learning, with distinct consequences for how surprises are incorporated into predictive mnemonic models of the environment. PMID:26854903

  3. Distinct medial temporal networks encode surprise during motivation by reward versus punishment.

    Science.gov (United States)

    Murty, Vishnu P; LaBar, Kevin S; Adcock, R Alison

    2016-10-01

    Adaptive motivated behavior requires predictive internal representations of the environment, and surprising events are indications for encoding new representations of the environment. The medial temporal lobe memory system, including the hippocampus and surrounding cortex, encodes surprising events and is influenced by motivational state. Because behavior reflects the goals of an individual, we investigated whether motivational valence (i.e., pursuing rewards versus avoiding punishments) also impacts neural and mnemonic encoding of surprising events. During functional magnetic resonance imaging (fMRI), participants encountered perceptually unexpected events either during the pursuit of rewards or avoidance of punishments. Despite similar levels of motivation across groups, reward and punishment facilitated the processing of surprising events in different medial temporal lobe regions. Whereas during reward motivation, perceptual surprises enhanced activation in the hippocampus, during punishment motivation surprises instead enhanced activation in parahippocampal cortex. Further, we found that reward motivation facilitated hippocampal coupling with ventromedial PFC, whereas punishment motivation facilitated parahippocampal cortical coupling with orbitofrontal cortex. Behaviorally, post-scan testing revealed that reward, but not punishment, motivation resulted in greater memory selectivity for surprising events encountered during goal pursuit. Together these findings demonstrate that neuromodulatory systems engaged by anticipation of reward and punishment target separate components of the medial temporal lobe, modulating medial temporal lobe sensitivity and connectivity. Thus, reward and punishment motivation yield distinct neural contexts for learning, with distinct consequences for how surprises are incorporated into predictive mnemonic models of the environment. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Surprisingly rational: probability theory plus noise explains biases in judgment.

    Science.gov (United States)

    Costello, Fintan; Watts, Paul

    2014-07-01

    The systematic biases seen in people's probability judgments are typically taken as evidence that people do not use the rules of probability theory when reasoning about probability but instead use heuristics, which sometimes yield reasonable judgments and sometimes yield systematic biases. This view has had a major impact in economics, law, medicine, and other fields; indeed, the idea that people cannot reason with probabilities has become a truism. We present a simple alternative to this view, where people reason about probability according to probability theory but are subject to random variation or noise in the reasoning process. In this account the effect of noise is canceled for some probabilistic expressions. Analyzing data from 2 experiments, we find that, for these expressions, people's probability judgments are strikingly close to those required by probability theory. For other expressions, this account produces systematic deviations in probability estimates. These deviations explain 4 reliable biases in human probabilistic reasoning (conservatism, subadditivity, conjunction, and disjunction fallacies). These results suggest that people's probability judgments embody the rules of probability theory and that biases in those judgments are due to the effects of random noise. (c) 2014 APA, all rights reserved.

  5. Can surprising nonreward and adjunctive behavior influence each other?

    Directory of Open Access Journals (Sweden)

    Patricia Rick

    2018-02-01

    Full Text Available Adjunctive or schedule-induced behavior can be defined as an increase in the frequency of a behavior under conditions of intermittent reinforcement. Adjunctive behavior has been explained as developing from reinforcement contingencies and emotional responses of frustration due to periods of reward omission, among other accounts. Two experiments with rats were designed to test the hypothesis that frustration mediates adjunctive behavior. According to this hypothesis, extensive training under conditions involving both reward and reward omission (e.g., partial reinforcement and intermittent reinforcement promote frustration counterconditioning, a mechanism activated when reward omissions are followed by reward. Frustration counterconditioning reduces avoidance and enhances approach, inducing behavioral persistence that transfers across situations inducing frustration—a mechanism yielding transsituational transfer. In Experiment 1, Phase 1 involved runway training under continuous vs. partial food reinforcement, whereas Phase 2 involved exposure to a fixed-time 60-s schedule of intermittent food reinforcement with free access to a wheel. Counterconditioning of goal approach in Phase 1 led only to a modest increase in wheel running in Phase 2. In Experiment 2, Phase 1 involved groups exposed to either intermittent reinforcement or massed-food control, both with access to a wheel, followed in Phase 2 by runway training under continuous reinforcement and extinction. No support was found for a transfer effect. The results are discussed in relation to accounts of adjunctive behavior based on Amsel’s frustration theory and Killeen-Pellón’s reinforcement theory of adjunctive behavior.

  6. Interest in smart metering project surprises utility, IBM

    International Nuclear Information System (INIS)

    Horne, D.

    2006-01-01

    This article provided an outline of Hydro Ottawa and IBM's smart metering pilot project, which has resulted in high approval ratings from the public. The project features 375 participants broken down into 3 separate groups to look for potential consumption differences between customers charged according to standard time-of-use pricing; time-of-use with critical peak pricing; and time-of-use with critical peak rebates. The Ontario Smart Price Pilot project will be run for 5 months, and is expected to provide detailed energy information about usage. Past projects have indicated that customers respond quickly to smart metering, as they are able to monitor their energy usage and more effectively manage their energy consumption. Ontario plans to have all homes and small businesses using smart meters by 2010, as high seasonal demand has indicated that conservation and balanced resource use are now top priorities for many utility companies. At least 10 states in the United States have conducted smart metering pilot projects. The California Public Utilities Commissions has recently approved a $1.7 billion statewide plan to replace old meters with smart meters. In Ontario, customers have ordered 10,000 electricity monitors that Hydro One is giving away. It was concluded that research results from an earlier Hydro One demonstration project with 500 Ontario homeowners showed that real time electricity monitors can help homeowners reduce their consumption of electricity by up to 15 per cent. 4 figs

  7. SURPRISINGLY WEAK MAGNETISM ON YOUNG ACCRETING BROWN DWARFS

    International Nuclear Information System (INIS)

    Reiners, A.; Basri, G.; Christensen, U. R.

    2009-01-01

    We have measured the surface magnetic flux on four accreting young brown dwarfs and one nonaccreting young very low mass (VLM) star utilizing high-resolution spectra of absorption lines of the FeH molecule. A magnetic field of 1-2 kG had been proposed for one of the brown dwarfs, Two Micron All Sky Survey (2MASS) J1207334-393254, because of its similarities to higher mass T Tauri stars as manifested in accretion and the presence of a jet. We do not find clear evidence for a kilogauss field in any of our young brown dwarfs but do find a 2 kG field on the young VLM star. Our 3σ upper limit for the magnetic flux in 2MASS J1207334-393254 just reaches 1 kG. We estimate the magnetic field required for accretion in young brown dwarfs given the observed rotations, and find that fields of only a few hundred gauss are sufficient for magnetospheric accretion. This predicted value is less than our observed upper limit. We conclude that magnetic fields in young brown dwarfs are a factor of 5 or more lower than in young stars of about one solar mass, and in older stars with spectral types similar to our young brown dwarfs. It is interesting that, during the first few million years, the fields scale down with mass in line with what is needed for magnetospheric accretion, yet no such scaling is observed at later ages within the same effective temperature range. This scaling is opposite to the trend in rotation, with shorter rotation periods for very young accreting brown dwarfs compared with accreting solar-mass objects (and very low Rossby numbers in all cases). We speculate that in young objects a deeper intrinsic connection may exist between magnetospheric accretion and magnetic field strength, or that magnetic field generation in brown dwarfs may be less efficient than in stars. Neither of these currently has an easy physical explanation.

  8. A Contrast-Based Computational Model of Surprise and Its Applications.

    Science.gov (United States)

    Macedo, Luis; Cardoso, Amílcar

    2017-11-19

    We review our work on a contrast-based computational model of surprise and its applications. The review is contextualized within related research from psychology, philosophy, and particularly artificial intelligence. Influenced by psychological theories of surprise, the model assumes that surprise-eliciting events initiate a series of cognitive processes that begin with the appraisal of the event as unexpected, continue with the interruption of ongoing activity and the focusing of attention on the unexpected event, and culminate in the analysis and evaluation of the event and the revision of beliefs. It is assumed that the intensity of surprise elicited by an event is a nonlinear function of the difference or contrast between the subjective probability of the event and that of the most probable alternative event (which is usually the expected event); and that the agent's behavior is partly controlled by actual and anticipated surprise. We describe applications of artificial agents that incorporate the proposed surprise model in three domains: the exploration of unknown environments, creativity, and intelligent transportation systems. These applications demonstrate the importance of surprise for decision making, active learning, creative reasoning, and selective attention. Copyright © 2017 Cognitive Science Society, Inc.

  9. The influence of psychological resilience on the relation between automatic stimulus evaluation and attentional breadth for surprised faces.

    Science.gov (United States)

    Grol, Maud; De Raedt, Rudi

    2015-01-01

    The broaden-and-build theory relates positive emotions to resilience and cognitive broadening. The theory proposes that the broadening effects underly the relation between positive emotions and resilience, suggesting that resilient people can benefit more from positive emotions at the level of cognitive functioning. Research has investigated the influence of positive emotions on attentional broadening, but the stimulus in the target of attention may also influence attentional breadth, depending on affective stimulus evaluation. Surprised faces are particularly interesting as they are valence ambiguous, therefore, we investigated the relation between affective evaluation--using an affective priming task--and attentional breadth for surprised faces, and how this relation is influenced by resilience. Results show that more positive evaluations are related to more attentional broadening at high levels of resilience, while this relation is reversed at low levels. This indicates that resilient individuals can benefit more from attending to positively evaluated stimuli at the level of attentional broadening.

  10. A Statistical Analysis of the Relationship between Harmonic Surprise and Preference in Popular Music.

    Science.gov (United States)

    Miles, Scott A; Rosen, David S; Grzywacz, Norberto M

    2017-01-01

    Studies have shown that some musical pieces may preferentially activate reward centers in the brain. Less is known, however, about the structural aspects of music that are associated with this activation. Based on the music cognition literature, we propose two hypotheses for why some musical pieces are preferred over others. The first, the Absolute-Surprise Hypothesis, states that unexpected events in music directly lead to pleasure. The second, the Contrastive-Surprise Hypothesis, proposes that the juxtaposition of unexpected events and subsequent expected events leads to an overall rewarding response. We tested these hypotheses within the framework of information theory, using the measure of "surprise." This information-theoretic variable mathematically describes how improbable an event is given a known distribution. We performed a statistical investigation of surprise in the harmonic structure of songs within a representative corpus of Western popular music, namely, the McGill Billboard Project corpus. We found that chords of songs in the top quartile of the Billboard chart showed greater average surprise than those in the bottom quartile. We also found that the different sections within top-quartile songs varied more in their average surprise than the sections within bottom-quartile songs. The results of this study are consistent with both the Absolute- and Contrastive-Surprise Hypotheses. Although these hypotheses seem contradictory to one another, we cannot yet discard the possibility that both absolute and contrastive types of surprise play roles in the enjoyment of popular music. We call this possibility the Hybrid-Surprise Hypothesis. The results of this statistical investigation have implications for both music cognition and the human neural mechanisms of esthetic judgments.

  11. Surprises from a Deep ASCA Spectrum of the Broad Absorption Line Quasar PHL 5200

    Science.gov (United States)

    Mathur, Smita; Matt, G.; Green, P. J.; Elvis, M.; Singh, K. P.

    2002-01-01

    We present a deep (approx. 85 ks) ASCA observation of the prototype broad absorption line quasar (BALQSO) PHL 5200. This is the best X-ray spectrum of a BALQSO yet. We find the following: (1) The source is not intrinsically X-ray weak. (2) The line-of-sight absorption is very strong, with N(sub H) = 5 x 10(exp 23)/sq cm. (3) The absorber does not cover the source completely; the covering fraction is approx. 90%. This is consistent with the large optical polarization observed in this source, implying multiple lines of sight. The most surprising result of this observation is that (4) the spectrum of this BALQSO is not exactly similar to other radio-quiet quasars. The hard X-ray spectrum of PHL 5200 is steep, with the power-law spectral index alpha approx. 1.5. This is similar to the steepest hard X-ray slopes observed so far. At low redshifts, such steep slopes are observed in narrow-line Seyfert 1 (NLS1) galaxies, believed to be accreting at a high Eddington rate. This observation strengthens the analogy between BALQSOs and NLS1 galaxies and supports the hypothesis that BALQSOs represent an early evolutionary state of quasars. It is well accepted that the orientation to the line of sight determines the appearance of a quasar: age seems to play a significant role as well.

  12. Summit surprises.

    Science.gov (United States)

    Myers, N

    1994-01-01

    A New Delhi Population Summit, organized by the Royal Society, the US National Academy of Sciences, the Royal Swedish Academy of Sciences, and the Indian National Science Academy, was convened with representation of 120 (only 10% women) scientists from 50 countries and about 12 disciplines and 43 national scientific academies. Despite the common assumption that scientists never agree, a 3000 word statement was signed by 50 prominent national figures and supported by 25 professional papers on diverse subjects. The statement proclaimed that stable world population and "prodigious planning efforts" are required for dealing with global social, economic, and environmental problems. The target should be zero population growth by the next generation. The statement, although containing many uncompromising assertions, was not as strong as a statement by the Royal Society and the US National Academy of Sciences released last year: that, in the future, science and technology may not be able to prevent "irreversible degradation of the environment and continued poverty," and that the capacity to sustain life on the planet may be permanently jeopardized. The Delhi statement was backed by professional papers highlighting several important issues. Dr Mahmoud Fathalla of the Rockefeller Foundation claimed that the 500,000 annual maternal deaths worldwide, of which perhaps 33% are due to "coathanger" abortions, are given far less attention than a one-day political event of 500 deaths would receive. Although biologically women have been given a greater survival advantage, which is associated with their reproductive capacity, socially disadvantaged females are relegated to low status. There is poorer nutrition and overall health care for females, female infanticide, and female fetuses are increasingly aborted in China, India, and other countries. The sex ratio in developed countries is 95-97 males to every 100 females, but in developing Asian countries the ratio is 105 males to 100 females. There are reports of 60-100 million missing females. The human species 12,000 years ago had a population of 6 million, a life expectancy of 20 years, and a doubling time of 8000 years; high birth rates were important for preservation of the species. Profertility attitudes are still prevalent today. Insufficient funds go to contraceptive research.

  13. Hypersingular integral equations, waveguiding effects in Cantorian Universe and genesis of large scale structures

    International Nuclear Information System (INIS)

    Iovane, G.; Giordano, P.

    2005-01-01

    In this work we introduce the hypersingular integral equations and analyze a realistic model of gravitational waveguides on a cantorian space-time. A waveguiding effect is considered with respect to the large scale structure of the Universe, where the structure formation appears as if it were a classically self-similar random process at all astrophysical scales. The result is that it seems we live in an El Naschie's o (∞) Cantorian space-time, where gravitational lensing and waveguiding effects can explain the appearing Universe. In particular, we consider filamentary and planar large scale structures as possible refraction channels for electromagnetic radiation coming from cosmological structures. From this vision the Universe appears like a large self-similar adaptive mirrors set, thanks to three numerical simulations. Consequently, an infinite Universe is just an optical illusion that is produced by mirroring effects connected with the large scale structure of a finite and not a large Universe

  14. Effects of uncertainty in model predictions of individual tree volume on large area volume estimates

    Science.gov (United States)

    Ronald E. McRoberts; James A. Westfall

    2014-01-01

    Forest inventory estimates of tree volume for large areas are typically calculated by adding model predictions of volumes for individual trees. However, the uncertainty in the model predictions is generally ignored with the result that the precision of the large area volume estimates is overestimated. The primary study objective was to estimate the effects of model...

  15. Estimating the Effectiveness of Special Education Using Large-Scale Assessment Data

    Science.gov (United States)

    Ewing, Katherine Anne

    2009-01-01

    The inclusion of students with disabilities in large scale assessment and accountability programs has provided new opportunities to examine the impact of special education services on student achievement. Hanushek, Kain, and Rivkin (1998, 2002) evaluated the effectiveness of special education programs by examining students' gains on a large-scale…

  16. Distinct medial temporal networks encode surprise during motivation by reward versus punishment

    OpenAIRE

    Murty, Vishnu P.; LaBar, Kevin S.; Adcock, R. Alison

    2016-01-01

    Adaptive motivated behavior requires predictive internal representations of the environment, and surprising events are indications for encoding new representations of the environment. The medial temporal lobe memory system, including the hippocampus and surrounding cortex, encodes surprising events and is influenced by motivational state. Because behavior reflects the goals of an individual, we investigated whether motivational valence (i.e., pursuing rewards versus avoiding punishments) also...

  17. Communication Management and Trust: Their Role in Building Resilience to "Surprises" Such As Natural Disasters, Pandemic Flu, and Terrorism

    Directory of Open Access Journals (Sweden)

    P. H. Longstaff

    2008-06-01

    Full Text Available In times of public danger such as natural disasters and health emergencies, a country's communication systems will be some of its most important assets because access to information will make individuals and groups more resilient. Communication by those charged with dealing with the situation is often critical. We analyzed reports from a wide variety of crisis incidents and found a direct correlation between trust and an organization's preparedness and internal coordination of crisis communication and the effectiveness of its leadership. Thus, trust is one of the most important variables in effective communication management in times of "surprise."

  18. Ignorance, Vulnerability and the Occurrence of "Radical Surprises": Theoretical Reflections and Empirical Findings

    Science.gov (United States)

    Kuhlicke, C.

    2009-04-01

    By definition natural disasters always contain a moment of surprise. Their occurrence is mostly unforeseen and unexpected. They hit people unprepared, overwhelm them and expose their helplessness. Yet, there is surprisingly little known on the reasons for their being surprised. Aren't natural disasters expectable and foreseeable after all? Aren't the return rates of most hazards well known and shouldn't people be better prepared? The central question of this presentation is hence: Why do natural disasters so often radically surprise people at all (and how can we explain this being surprised)? In the first part of the presentation, it is argued that most approaches to vulnerability are not able to grasp this moment of surprise. On the contrary, they have their strength in unravelling the expectable: A person who is marginalized or even oppressed in everyday life is also vulnerable during times of crisis and stress, at least this is the central assumption of most vulnerability studies. In the second part, an understanding of vulnerability is developed, which allows taking into account such radical surprises. First, two forms of the unknown are differentiated: An area of the unknown an actor is more or less aware of (ignorance), and an area, which is not even known to be not known (nescience). The discovery of the latter is mostly associated with a "radical surprise", since it is per definition impossible to prepare for it. Second, a definition of vulnerability is proposed, which allows capturing the dynamics of surprises: People are vulnerable when they discover their nescience exceeding by definition previously established routines, stocks of knowledge and resources—in a general sense their capacities—to deal with their physical and/or social environment. This definition explicitly takes the view of different actors serious and departs from their being surprised. In the third part findings of a case study are presented, the 2002 flood in Germany. It is shown

  19. Large Data Set Mining

    NARCIS (Netherlands)

    Leemans, I.B.; Broomhall, Susan

    2017-01-01

    Digital emotion research has yet to make history. Until now large data set mining has not been a very active field of research in early modern emotion studies. This is indeed surprising since first, the early modern field has such rich, copyright-free, digitized data sets and second, emotion studies

  20. Surprise responses in the human brain demonstrate statistical learning under high concurrent cognitive demand

    Science.gov (United States)

    Garrido, Marta Isabel; Teng, Chee Leong James; Taylor, Jeremy Alexander; Rowe, Elise Genevieve; Mattingley, Jason Brett

    2016-06-01

    The ability to learn about regularities in the environment and to make predictions about future events is fundamental for adaptive behaviour. We have previously shown that people can implicitly encode statistical regularities and detect violations therein, as reflected in neuronal responses to unpredictable events that carry a unique prediction error signature. In the real world, however, learning about regularities will often occur in the context of competing cognitive demands. Here we asked whether learning of statistical regularities is modulated by concurrent cognitive load. We compared electroencephalographic metrics associated with responses to pure-tone sounds with frequencies sampled from narrow or wide Gaussian distributions. We showed that outliers evoked a larger response than those in the centre of the stimulus distribution (i.e., an effect of surprise) and that this difference was greater for physically identical outliers in the narrow than in the broad distribution. These results demonstrate an early neurophysiological marker of the brain's ability to implicitly encode complex statistical structure in the environment. Moreover, we manipulated concurrent cognitive load by having participants perform a visual working memory task while listening to these streams of sounds. We again observed greater prediction error responses in the narrower distribution under both low and high cognitive load. Furthermore, there was no reliable reduction in prediction error magnitude under high-relative to low-cognitive load. Our findings suggest that statistical learning is not a capacity limited process, and that it proceeds automatically even when cognitive resources are taxed by concurrent demands.

  1. Pseudohalide (SCN(-))-Doped MAPbI3 Perovskites: A Few Surprises.

    Science.gov (United States)

    Halder, Ansuman; Chulliyil, Ramya; Subbiah, Anand S; Khan, Tuhin; Chattoraj, Shyamtanu; Chowdhury, Arindam; Sarkar, Shaibal K

    2015-09-03

    Pseudohalide thiocyanate anion (SCN(-)) has been used as a dopant in a methylammonium lead tri-iodide (MAPbI3) framework, aiming for its use as an absorber layer for photovoltaic applications. The substitution of SCN(-) pseudohalide anion, as verified using Fourier transform infrared (FT-IR) spectroscopy, results in a comprehensive effect on the optical properties of the original material. Photoluminescence measurements at room temperature reveal a significant enhancement in the emission quantum yield of MAPbI3-x(SCN)x as compared to MAPbI3, suggestive of suppression of nonradiative channels. This increased intensity is attributed to a highly edge specific emission from MAPbI3-x(SCN)x microcrystals as revealed by photoluminescence microscopy. Fluoresence lifetime imaging measurements further established contrasting carrier recombination dynamics for grain boundaries and the bulk of the doped material. Spatially resolved emission spectroscopy on individual microcrystals of MAPbI3-x(SCN)x reveals that the optical bandgap and density of states at various (local) nanodomains are also nonuniform. Surprisingly, several (local) emissive regions within MAPbI3-x(SCN)x microcrystals are found to be optically unstable under photoirradiation, and display unambiguous temporal intermittency in emission (blinking), which is extremely unusual and intriguing. We find diverse blinking behaviors for the undoped MAPbI3 crystals as well, which leads us to speculate that blinking may be a common phenomenon for most hybrid perovskite materials.

  2. Effects of electrolyte gating on photoluminescence spectra of large-area WSe2monolayer films

    KAUST Repository

    Matsuki, Keiichiro; Pu, Jiang; Kozawa, Daichi; Matsuda, Kazunari; Li, Lain-Jong; Takenobu, Taishi

    2016-01-01

    We fabricated electric double-layer transistors comprising large-area WSe2 monolayers and investigated the effects of electrolyte gating on their photoluminescence (PL) spectra. Using the efficient gating effects of electric double layers, we succeeded in the application of a large electric field (>107Vcm%1) and the accumulation of high carrier density (>1013cm%2). As a result, we observed PL spectra based on both positively and negatively charged excitons and their gate-voltage-dependent redshifts, suggesting the effects of both an electric field and charge accumulation. © 2016 The Japan Society of Applied Physics.

  3. Effects of electrolyte gating on photoluminescence spectra of large-area WSe2monolayer films

    KAUST Repository

    Matsuki, Keiichiro

    2016-05-24

    We fabricated electric double-layer transistors comprising large-area WSe2 monolayers and investigated the effects of electrolyte gating on their photoluminescence (PL) spectra. Using the efficient gating effects of electric double layers, we succeeded in the application of a large electric field (>107Vcm%1) and the accumulation of high carrier density (>1013cm%2). As a result, we observed PL spectra based on both positively and negatively charged excitons and their gate-voltage-dependent redshifts, suggesting the effects of both an electric field and charge accumulation. © 2016 The Japan Society of Applied Physics.

  4. Effects of cell asymmetry on the performance of a large heterogeneous critical assembly

    International Nuclear Information System (INIS)

    Scholtyssek, W.; Humbert, G.; Martini, M.; Norvez, G.

    1981-09-01

    Calculations were performed to investigate asymmetry effects observed in the RACINE reference configuration. The perturbation sources -material shifts in fissile rodlet cells- were identified and influences on various experimental parameters were estimated. Improvements of the relatively simple methods used in this work could lead to applications, considering similar effects, in project calculations for large power reactor cores

  5. Effectiveness of feeding large kibbles with mechanical cleaning properties in cats with gingivitis

    NARCIS (Netherlands)

    Vrieling, HE; Theyse, LFH; van Winkelhoff, AJ; Dijkshoorn, NA; Logan, EI; Picovet, P

    2005-01-01

    Effectiveness of feeding large kibbles with mechanical cleaning properties in cats with gingivitis periodontal disease is the most common acquired oral disease in cats. it starts with plaque accumulation and gingivitis. The aim of this study was to evaluate the effectiveness of different types of

  6. Large-order behavior of nondecoupling effects in the standard model and triviality

    International Nuclear Information System (INIS)

    Aoki, K.

    1994-01-01

    We compute some nondecoupling effects in the standard model, such as the ρ parameter, to all orders in the coupling constant expansion. We analyze their large order behavior and explicitly show how they are related to the nonperturbative cutoff dependence of these nondecoupling effects due to the triviality of the theory

  7. A surprisingly simple correlation between the classical and quantum structural networks in liquid water

    Science.gov (United States)

    Hamm, Peter; Fanourgakis, George S.; Xantheas, Sotiris S.

    2017-08-01

    Nuclear quantum effects in liquid water have profound implications for several of its macroscopic properties related to the structure, dynamics, spectroscopy, and transport. Although several of water's macroscopic properties can be reproduced by classical descriptions of the nuclei using interaction potentials effectively parameterized for a narrow range of its phase diagram, a proper account of the nuclear quantum effects is required to ensure that the underlying molecular interactions are transferable across a wide temperature range covering different regions of that diagram. When performing an analysis of the hydrogen-bonded structural networks in liquid water resulting from the classical (class) and quantum (qm) descriptions of the nuclei with two interaction potentials that are at the two opposite ends of the range in describing quantum effects, namely the flexible, pair-wise additive q-TIP4P/F, and the flexible, polarizable TTM3-F, we found that the (class) and (qm) results can be superimposed over the temperature range T = 250-350 K using a surprisingly simple, linear scaling of the two temperatures according to T(qm) = α T(class) + ΔT, where α = 0.99 and ΔT = -6 K for q-TIP4P/F and α = 1.24 and ΔT = -64 K for TTM3-F. This simple relationship suggests that the structural networks resulting from the quantum and classical treatment of the nuclei with those two very different interaction potentials are essentially similar to each other over this extended temperature range once a model-dependent linear temperature scaling law is applied.

  8. Herbivore grazing—or trampling? Trampling effects by a large ungulate in cold high- latitude ecosystems

    OpenAIRE

    Heggenes, Jan; Odland, Arvid; Chevalier, Tomas; Ahlberg, Jörgen; Berg, Amanda; Larsson, Håkan; Bjerketvedt, Dag Kjartan

    2017-01-01

    Mammalian herbivores have important top-down effects on ecological processes and landscapes by generating vegetation changes through grazing and trampling. For free-ranging herbivores on large landscapes, trampling is an important ecological factor. However, whereas grazing is widely studied, low-intensity trampling is rarely studied and quantified. The cold-adapted northern tundra reindeer (Rangifer tarandus) is a wide-ranging keystone herbivore in large open alpine and Arctic ecosystems. Re...

  9. On the Renormalization of the Effective Field Theory of Large Scale Structures

    OpenAIRE

    Pajer, Enrico; Zaldarriaga, Matias

    2013-01-01

    Standard perturbation theory (SPT) for large-scale matter inhomogeneities is unsatisfactory for at least three reasons: there is no clear expansion parameter since the density contrast is not small on all scales; it does not fully account for deviations at large scales from a perfect pressureless fluid induced by short-scale non-linearities; for generic initial conditions, loop corrections are UV-divergent, making predictions cutoff dependent and hence unphysical. The Effective Field Theory o...

  10. A Simple Method to Estimate Large Fixed Effects Models Applied to Wage Determinants and Matching

    OpenAIRE

    Mittag, Nikolas

    2016-01-01

    Models with high dimensional sets of fixed effects are frequently used to examine, among others, linked employer-employee data, student outcomes and migration. Estimating these models is computationally difficult, so simplifying assumptions that are likely to cause bias are often invoked to make computation feasible and specification tests are rarely conducted. I present a simple method to estimate large two-way fixed effects (TWFE) and worker-firm match effect models without additional assum...

  11. A Methodology of Estimation on Air Pollution and Its Health Effects in Large Japanese Cities

    OpenAIRE

    Hirota, Keiko; Shibuya, Satoshi; Sakamoto, Shogo; Kashima, Shigeru

    2012-01-01

    The correlation between air pollution and health effects in large Japanese cities presents a great challenge owing to the limited availability of data on the exposure to pollution, health effects and the uncertainty of mixed causes. A methodology for quantitative relationships (between the emission volume and air quality, and the air quality and health effects) is analysed with a statistical method in this article; the correlation of air pollution reduction policy in Japan from 1974 to 2007. ...

  12. The Impact of a Surprise Dividend Increase on a Stocks Performance : the Analysis of Companies Listed on the Warsaw Stock Exchange

    Directory of Open Access Journals (Sweden)

    Tomasz Słoński

    2012-01-01

    Full Text Available The reaction of marginal investors to the announcement of a surprise dividend increase has been measured. Although field research is performed on companies listed on the Warsaw Stock Exchange, the paper has important theoretical implications. Valuation theory gives many clues for the interpretation of changes in dividends. At the start of the literature review, the assumption of the irrelevance of dividends (to investment decisions is described. This assumption is the basis for up-to-date valuation procedures leading to fundamental and fair market valuation of equity (shares. The paper is designed to verify whether the market value of stock is immune to the surprise announcement of a dividend increase. This study of the effect of a surprise dividend increase gives the chance to partially isolate such an event from dividend changes based on long-term expectations. The result of the research explicitly shows that a surprise dividend increase is on average welcomed by investors (an average abnormal return of 2.24% with an associated p-value of 0.001. Abnormal returns are realized by investors when there is a surprise increase in a dividend payout. The subsample of relatively high increases in a dividend payout enables investors to gain a 3.2% return on average. The results show that valuation models should be revised to take into account a possible impact of dividend changes on investors behavior. (original abstract

  13. Imprint of non-linear effects on HI intensity mapping on large scales

    Energy Technology Data Exchange (ETDEWEB)

    Umeh, Obinna, E-mail: umeobinna@gmail.com [Department of Physics and Astronomy, University of the Western Cape, Cape Town 7535 (South Africa)

    2017-06-01

    Intensity mapping of the HI brightness temperature provides a unique way of tracing large-scale structures of the Universe up to the largest possible scales. This is achieved by using a low angular resolution radio telescopes to detect emission line from cosmic neutral Hydrogen in the post-reionization Universe. We use general relativistic perturbation theory techniques to derive for the first time the full expression for the HI brightness temperature up to third order in perturbation theory without making any plane-parallel approximation. We use this result and the renormalization prescription for biased tracers to study the impact of nonlinear effects on the power spectrum of HI brightness temperature both in real and redshift space. We show how mode coupling at nonlinear order due to nonlinear bias parameters and redshift space distortion terms modulate the power spectrum on large scales. The large scale modulation may be understood to be due to the effective bias parameter and effective shot noise.

  14. What is a surprise earthquake? The example of the 2002, San Giuliano (Italy event

    Directory of Open Access Journals (Sweden)

    M. Mucciarelli

    2005-06-01

    Full Text Available Both in scientific literature and in the mass media, some earthquakes are defined as «surprise earthquakes». Based on his own judgment, probably any geologist, seismologist or engineer may have his own list of past «surprise earthquakes». This paper tries to quantify the underlying individual perception that may lead a scientist to apply such a definition to a seismic event. The meaning is different, depending on the disciplinary approach. For geologists, the Italian database of seismogenic sources is still too incomplete to allow for a quantitative estimate of the subjective degree of belief. For seismologists, quantification is possible defining the distance between an earthquake and its closest previous neighbor. Finally, for engineers, the San Giuliano quake could not be considered a surprise, since probabilistic site hazard estimates reveal that the change before and after the earthquake is just 4%.

  15. Conference of “Uncertainty and Surprise: Questions on Working with the Unexpected and Unknowable”

    CERN Document Server

    McDaniel, Reuben R; Uncertainty and Surprise in Complex Systems : Questions on Working with the Unexpected

    2005-01-01

    Complexity science has been a source of new insight in physical and social systems and has demonstrated that unpredictability and surprise are fundamental aspects of the world around us. This book is the outcome of a discussion meeting of leading scholars and critical thinkers with expertise in complex systems sciences and leaders from a variety of organizations sponsored by the Prigogine Center at The University of Texas at Austin and the Plexus Institute to explore strategies for understanding uncertainty and surprise. Besides distributions to the conference it includes a key digest by the editors as well as a commentary by the late nobel laureat Ilya Prigogine, "Surprises in half of a century". The book is intended for researchers and scientists in complexity science as well as for a broad interdisciplinary audience of both practitioners and scholars. It will well serve those interested in the research issues and in the application of complexity science to physical and social systems.

  16. Vlasov simulation of the relativistic effect on the breaking of large amplitude plasma waves

    International Nuclear Information System (INIS)

    Xu Hui; Sheng Zhengming; Zhang Jie

    2007-01-01

    The influence of relativistic and thermal effects on plasma wave breaking has been studied by solving the coupled Vlasov-Poisson equations. When the relativistic effect is not considered, the wave breaking will not occur, provided the initial perturbation is less than certain value as predicted previously, and the largest amplitude of the plasma wave will decrease with the increase of the initial temperature. When the relativistic effect is considered, wave breaking always occurs during the time evolution, irrespective of the initial perturbation amplitude. Yet the smaller the initial perturbation amplitude is, the longer is the time for wave breaking to occur. With large initial perturbations, wave breaking can always occur with the without the relativistic effect. However, the results are significantly different in the two cases. The thermal effects of electrons decrease the threshold value to initial amplitude for wave breaking and large phase velocity makes the nonlinear phenomenon occur more easily. (authors)

  17. Large Differences in the Optical Spectrum Associated with the Same Complex: The Effect of the Anisotropy of the Embedding Lattice

    DEFF Research Database (Denmark)

    Aramburu, José Antonio; García-Fernández, Pablo; García Lastra, Juan Maria

    2017-01-01

    of the electric field created by the rest of lattice ions over the complex. To illustrate this concept we analyze the origin of the surprisingly large differences in the d–d optical transitions of two systems containing square-planar CuF42– complexes, CaCuF4, and center II in Cu2+-doped Ba2ZnF6, even though...... the Cu2+–F–distance difference is just found to be 1%. Using a minimalist first-principles model we show that the different morphology of the host lattices creates an anisotropic field that red-shifts the in vacuo complex transitions to the 1.25–1.70 eV range in CaCuF4, while it blue-shifts them to the 1...

  18. Salience and attention in surprisal-based accounts of language processing

    Directory of Open Access Journals (Sweden)

    Alessandra eZarcone

    2016-06-01

    Full Text Available The notion of salience has been singled out as the explanatory factor for a diverse range oflinguistic phenomena. In particular, perceptual salience (e.g. visual salience of objects in the world,acoustic prominence of linguistic sounds and semantic-pragmatic salience (e.g. prominence ofrecently mentioned or topical referents have been shown to influence language comprehensionand production. A different line of research has sought to account for behavioral correlates ofcognitive load during comprehension as well as for certain patterns in language usage usinginformation-theoretic notions, such as surprisal. Surprisal and salience both affect languageprocessing at different levels, but the relationship between the two has not been adequatelyelucidated, and the question of whether salience can be reduced to surprisal / predictability isstill open. Our review identifies two main challenges in addressing this question: terminologicalinconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalise upon work in visual cognition inorder to orient ourselves in surveying the different facets of the notion of salience in linguisticsand their relation with models of surprisal. We find that work on salience highlights aspects oflinguistic communication that models of surprisal tend to overlook, namely the role of attentionand relevance to current goals, and we argue that the Predictive Coding framework provides aunified view which can account for the role played by attention and predictability at different levelsof processing and which can clarify the interplay between low and high levels of processes andbetween predictability-driven expectation and attention-driven focus.

  19. Salience and Attention in Surprisal-Based Accounts of Language Processing.

    Science.gov (United States)

    Zarcone, Alessandra; van Schijndel, Marten; Vogels, Jorrig; Demberg, Vera

    2016-01-01

    The notion of salience has been singled out as the explanatory factor for a diverse range of linguistic phenomena. In particular, perceptual salience (e.g., visual salience of objects in the world, acoustic prominence of linguistic sounds) and semantic-pragmatic salience (e.g., prominence of recently mentioned or topical referents) have been shown to influence language comprehension and production. A different line of research has sought to account for behavioral correlates of cognitive load during comprehension as well as for certain patterns in language usage using information-theoretic notions, such as surprisal. Surprisal and salience both affect language processing at different levels, but the relationship between the two has not been adequately elucidated, and the question of whether salience can be reduced to surprisal / predictability is still open. Our review identifies two main challenges in addressing this question: terminological inconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalize upon work in visual cognition in order to orient ourselves in surveying the different facets of the notion of salience in linguistics and their relation with models of surprisal. We find that work on salience highlights aspects of linguistic communication that models of surprisal tend to overlook, namely the role of attention and relevance to current goals, and we argue that the Predictive Coding framework provides a unified view which can account for the role played by attention and predictability at different levels of processing and which can clarify the interplay between low and high levels of processes and between predictability-driven expectation and attention-driven focus.

  20. Salience and Attention in Surprisal-Based Accounts of Language Processing

    Science.gov (United States)

    Zarcone, Alessandra; van Schijndel, Marten; Vogels, Jorrig; Demberg, Vera

    2016-01-01

    The notion of salience has been singled out as the explanatory factor for a diverse range of linguistic phenomena. In particular, perceptual salience (e.g., visual salience of objects in the world, acoustic prominence of linguistic sounds) and semantic-pragmatic salience (e.g., prominence of recently mentioned or topical referents) have been shown to influence language comprehension and production. A different line of research has sought to account for behavioral correlates of cognitive load during comprehension as well as for certain patterns in language usage using information-theoretic notions, such as surprisal. Surprisal and salience both affect language processing at different levels, but the relationship between the two has not been adequately elucidated, and the question of whether salience can be reduced to surprisal / predictability is still open. Our review identifies two main challenges in addressing this question: terminological inconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalize upon work in visual cognition in order to orient ourselves in surveying the different facets of the notion of salience in linguistics and their relation with models of surprisal. We find that work on salience highlights aspects of linguistic communication that models of surprisal tend to overlook, namely the role of attention and relevance to current goals, and we argue that the Predictive Coding framework provides a unified view which can account for the role played by attention and predictability at different levels of processing and which can clarify the interplay between low and high levels of processes and between predictability-driven expectation and attention-driven focus. PMID:27375525

  1. Risk, surprises and black swans fundamental ideas and concepts in risk assessment and risk management

    CERN Document Server

    Aven, Terje

    2014-01-01

    Risk, Surprises and Black Swans provides an in depth analysis of the risk concept with a focus on the critical link to knowledge; and the lack of knowledge, that risk and probability judgements are based on.Based on technical scientific research, this book presents a new perspective to help you understand how to assess and manage surprising, extreme events, known as 'Black Swans'. This approach looks beyond the traditional probability-based principles to offer a broader insight into the important aspects of uncertain events and in doing so explores the ways to manage them.

  2. Quantitative Missense Variant Effect Prediction Using Large-Scale Mutagenesis Data.

    Science.gov (United States)

    Gray, Vanessa E; Hause, Ronald J; Luebeck, Jens; Shendure, Jay; Fowler, Douglas M

    2018-01-24

    Large datasets describing the quantitative effects of mutations on protein function are becoming increasingly available. Here, we leverage these datasets to develop Envision, which predicts the magnitude of a missense variant's molecular effect. Envision combines 21,026 variant effect measurements from nine large-scale experimental mutagenesis datasets, a hitherto untapped training resource, with a supervised, stochastic gradient boosting learning algorithm. Envision outperforms other missense variant effect predictors both on large-scale mutagenesis data and on an independent test dataset comprising 2,312 TP53 variants whose effects were measured using a low-throughput approach. This dataset was never used for hyperparameter tuning or model training and thus serves as an independent validation set. Envision prediction accuracy is also more consistent across amino acids than other predictors. Finally, we demonstrate that Envision's performance improves as more large-scale mutagenesis data are incorporated. We precompute Envision predictions for every possible single amino acid variant in human, mouse, frog, zebrafish, fruit fly, worm, and yeast proteomes (https://envision.gs.washington.edu/). Copyright © 2017 Elsevier Inc. All rights reserved.

  3. An Audit of the Effectiveness of Large Group Neurology Tutorials for Irish Undergraduate Medical Students

    LENUS (Irish Health Repository)

    Kearney, H

    2016-07-01

    The aim of this audit was to determine the effectiveness of large group tutorials for teaching neurology to medical students. Students were asked to complete a questionnaire rating their confidence on a ten point Likert scale in a number of domains in the undergraduate education guidelines from the Association of British Neurologists (ABN). We then arranged a series of interactive large group tutorials for the class and repeated the questionnaire one month after teaching. In the three core domains of neurological: history taking, examination and differential diagnosis, none of the students rated their confidence as nine or ten out of ten prior to teaching. This increased to 6% for history taking, 12 % in examination and 25% for differential diagnosis after eight weeks of tutorials. This audit demonstrates that in our centre, large group tutorials were an effective means of teaching, as measured by the ABN guidelines in undergraduate neurology.

  4. Gluon bremstrahlung effects in large P/sub perpendicular/ hadron-hadron scattering

    International Nuclear Information System (INIS)

    Fox, G.C.; Kelly, R.L.

    1982-02-01

    We consider effects of parton (primarily gluon) bremstrahlung in the initial and final states of high transverse momentum hadron-hadron scattering. Monte Carlo calculations based on conventional QCD parton branching and scattering processes are presented. The calculations are carried only to the parton level in the final state. We apply the model to the Drell-Yan process and to high transverse momentum hadron-hadron scattering triggered with a large aperture calorimeter. We show that the latter triggers are biased in that they select events with unusually large bremstrahlung effects. We suggest that this trigger bias explains the large cross section and non-coplanar events observed in the NA5 experiment at the SPS

  5. Deciphering the clinical effect of drugs through large-scale data integration

    DEFF Research Database (Denmark)

    Kjærulff, Sonny Kim

    . This work demonstrates the power of a strategy that uses clinical data mining in association with chemical biology in order to reduce the search space and aid identification of novel drug actions. The second article described in chapter 3 outlines a high confidence side-effect-drug interaction dataset. We...... demonstrates the importance of using high-confidence drug-side-effect data in deciphering the effect of small molecules in humans. In summary, this thesis presents computational systems chemical biology approaches that can help identify clinical effects of small molecules through large-scale data integration...

  6. Absolute activity determinations on large volume geological samples independent of self-absorption effects

    International Nuclear Information System (INIS)

    Wilson, W.E.

    1980-01-01

    This paper describes a method for measuring the absolute activity of large volume samples by γ-spectroscopy independent of self-absorption effects using Ge detectors. The method yields accurate matrix independent results at the expense of replicative counting of the unknown sample. (orig./HP)

  7. Interactive effects of fire and large herbivores on web-building spiders.

    Science.gov (United States)

    Foster, C N; Barton, P S; Wood, J T; Lindenmayer, D B

    2015-09-01

    Altered disturbance regimes are a major driver of biodiversity loss worldwide. Maintaining or re-creating natural disturbance regimes is therefore the focus of many conservation programmes. A key challenge, however, is to understand how co-occurring disturbances interact to affect biodiversity. We experimentally tested for the interactive effects of prescribed fire and large macropod herbivores on the web-building spider assemblage of a eucalypt forest understorey and investigated the role of vegetation in mediating these effects using path analysis. Fire had strong negative effects on the density of web-building spiders, which were partly mediated by effects on vegetation structure, while negative effects of large herbivores on web density were not related to changes in vegetation. Fire amplified the effects of large herbivores on spiders, both via vegetation-mediated pathways and by increasing herbivore activity. The importance of vegetation-mediated pathways and fire-herbivore interactions differed for web density and richness and also differed between web types. Our results demonstrate that for some groups of web-building spiders, the effects of co-occurring disturbance drivers may be mostly additive, whereas for other groups, interactions between drivers can amplify disturbance effects. In our study system, the use of prescribed fire in the presence of high densities of herbivores could lead to reduced densities and altered composition of web-building spiders, with potential cascading effects through the arthropod food web. Our study highlights the importance of considering both the independent and interactive effects of disturbances, as well as the mechanisms driving their effects, in the management of disturbance regimes.

  8. Virtual Volatility, an Elementary New Concept with Surprising Stock Market Consequences

    Science.gov (United States)

    Prange, Richard; Silva, A. Christian

    2006-03-01

    Textbook investors start by predicting the future price distribution, PDF, of a candidate stock (or portfolio) at horizon T, e.g. a year hence. A (log)normal PDF with center (=drift =expected return) μT and width (=volatility) σT is often assumed on Central Limit Theorem grounds, i.e. by a random walk of daily (log)price increments δs. The standard deviation, stdev, of historical (ex post) δs `s is usually a fair predictor of the coming year's (ex ante) stdev(δs) = σdaily, but the historical mean E(δs) at best roughly limits the true, to be predicted, drift by μtrueT˜ μhistT ± σhistT. Textbooks take a PDF with σ ˜ σdaily and μ as somehow known, as if accurate predictions of μ were possible. It is elementary and presumably new to argue that an average of PDF's over a range of μ values should be taken, e.g. an average over forecasts by different analysts. We estimate that this leads to a PDF with a `virtual' volatility σ ˜ 1.3σdaily. It is indeed clear that uncertainty in the value of the expected gain parameter increases the risk of investment in that security by most measures, e. g. Sharpe's ratio μT/σT will be 30% smaller because of this effect. It is significant and surprising that there are investments which benefit from this 30% virtual increase in the volatility

  9. The Most Distant Mature Galaxy Cluster - Young, but surprisingly grown-up

    Science.gov (United States)

    2011-03-01

    Astronomers have used an armada of telescopes on the ground and in space, including the Very Large Telescope at ESO's Paranal Observatory in Chile to discover and measure the distance to the most remote mature cluster of galaxies yet found. Although this cluster is seen when the Universe was less than one quarter of its current age it looks surprisingly similar to galaxy clusters in the current Universe. "We have measured the distance to the most distant mature cluster of galaxies ever found", says the lead author of the study in which the observations from ESO's VLT have been used, Raphael Gobat (CEA, Paris). "The surprising thing is that when we look closely at this galaxy cluster it doesn't look young - many of the galaxies have settled down and don't resemble the usual star-forming galaxies seen in the early Universe." Clusters of galaxies are the largest structures in the Universe that are held together by gravity. Astronomers expect these clusters to grow through time and hence that massive clusters would be rare in the early Universe. Although even more distant clusters have been seen, they appear to be young clusters in the process of formation and are not settled mature systems. The international team of astronomers used the powerful VIMOS and FORS2 instruments on ESO's Very Large Telescope (VLT) to measure the distances to some of the blobs in a curious patch of very faint red objects first observed with the Spitzer space telescope. This grouping, named CL J1449+0856 [1], had all the hallmarks of being a very remote cluster of galaxies [2]. The results showed that we are indeed seeing a galaxy cluster as it was when the Universe was about three billion years old - less than one quarter of its current age [3]. Once the team knew the distance to this very rare object they looked carefully at the component galaxies using both the NASA/ESA Hubble Space Telescope and ground-based telescopes, including the VLT. They found evidence suggesting that most of the

  10. Dealing with unexpected events on the flight deck : A conceptual model of startle and surprise

    NARCIS (Netherlands)

    Landman, H.M.; Groen, E.L.; Paassen, M.M. van; Bronkhorst, A.W.; Mulder, M.

    2017-01-01

    Objective: A conceptual model is proposed in order to explain pilot performance in surprising and startling situations. Background: Today’s debate around loss of control following in-flight events and the implementation of upset prevention and recovery training has highlighted the importance of

  11. Bagpipes and Artichokes: Surprise as a Stimulus to Learning in the Elementary Music Classroom

    Science.gov (United States)

    Jacobi, Bonnie Schaffhauser

    2016-01-01

    Incorporating surprise into music instruction can stimulate student attention, curiosity, and interest. Novelty focuses attention in the reticular activating system, increasing the potential for brain memory storage. Elementary ages are ideal for introducing novel instruments, pieces, composers, or styles of music. Young children have fewer…

  12. The Educational Philosophies of Mordecai Kaplan and Michael Rosenak: Surprising Similarities and Illuminating Differences

    Science.gov (United States)

    Schein, Jeffrey; Caplan, Eric

    2014-01-01

    The thoughts of Mordecai Kaplan and Michael Rosenak present surprising commonalities as well as illuminating differences. Similarities include the perception that Judaism and Jewish education are in crisis, the belief that Jewish peoplehood must include commitment to meaningful content, the need for teachers to teach from a position of…

  13. Large-scale monitoring of effects of clothianidin-dressed OSR seeds on pollinating insects in Northern Germany: effects on large earth bumble bees (Bombus terrestris).

    Science.gov (United States)

    Sterk, Guido; Peters, Britta; Gao, Zhenglei; Zumkier, Ulrich

    2016-11-01

    The aim of this study was to investigate the effects of Elado ® -dressed winter oilseed rape (OSR, 10 g clothianidin & 2 g beta-cyfluthrin/kg seed) on the development, reproduction and behaviour of large earth bumble bees (Bombus terrestris) as part of a large-scale monitoring field study in Northern Germany, where OSR is usually cultivated at 25-33 % of the arable land. Both reference and test sites comprised 65 km 2 in which no other crops attractive to pollinating insects were present. Six study locations were selected per site and 10 bumble bee hives were placed at each location. At each site, three locations were directly adjacent to OSR fields and three locations were situated 400 m distant from the nearest OSR field. The development of colonies was monitored from the beginning of OSR flowering in April until June 2014. Pollen from returning foragers was analysed for its composition. An average of 44 % of OSR pollen was found in pollen loads of bumble bees indicating that OSR was a major resource for the colonies. At the end of OSR flowering, hives were transferred to a nature reserve until the end of the study. Colony development in terms of hive weight and the number of workers showed a typical course with no statistically significant differences between the sites. Reproductive output was comparatively high and not negatively affected by the exposure to treated OSR. In summary, Elado ® -dressed OSR did not cause any detrimental effects on the development or reproduction of bumble bee colonies.

  14. Effectiveness of a large mimic panel in an existing nuclear power plant central control board

    International Nuclear Information System (INIS)

    Kubota, Ryuji; Satoh, Hiroyuki; Sasajima, Katsuhiro; Kawano, Ryutaro; Shibuya Shinya

    1999-01-01

    We conducted the analysis of the nuclear power plant (NPP) operators' behaviors under emergency conditions by using training simulators as a joint research project by Japanese BWR groups for twelve years. In the phase-IV of this project we executed two kinds of experiments to evaluate the effectiveness of the interfaces. One was for evaluations of the interfaces such as CRTs with touch screen, a large mimic panel, and a hierarchical annunciator system introduced in the newly developed ABWR type central control board. The other was that we analyzed the operators' behaviors in emergency conditions by using the first generation BWR type central control board which was added new interfaces such as a large display screen and demarcation on the board to help operators to understand the plant. The demarcation is one of the visual interface improvements and its technique is that a line enclosing several components causes them to be perceived as a group.The result showed that both the large display panel Introduced in ABWR central control board and the large display screen in the existing BWR type central control board improved the performance of the NPP operators in the experiments. It was expected that introduction of the large mimic panel into the existing BWR type central control boards would improve operators' performance. However, in the case of actual installation of the large display board into the existing central control boards, there are spatial and hardware constraints. Therefore the size of lamps, lines connecting from symbols of the pumps or valves to the others' will have to be modified under these constraints. It is important to evaluate the displayed information on the large display board before actual installation. We made experiments to solve these problems by using TEPCO's research simulator which is added a large mimic panel. (author)

  15. Effect of thermal contact resistances on fast charging of large format lithium ion batteries

    International Nuclear Information System (INIS)

    Ye, Yonghuang; Saw, Lip Huat; Shi, Yixiang; Somasundaram, Karthik; Tay, Andrew A.O.

    2014-01-01

    Highlights: • The effect of thermal contact resistance on thermal performance of large format lithium ion batteries. • The effect of temperature gradient on electrochemical performance of large format batteries during fast charging. • The thermal performance of lithium ion battery utilizing pulse charging protocol. • Suggestions on battery geometry design optimization to improve thermal performance. - Abstract: A two dimensional electrochemical thermal model is developed on the cross-plane of a laminate stack plate pouch lithium ion battery to study the thermal performance of large format batteries. The effect of thermal contact resistance is taken into consideration, and is found to greatly increase the maximum temperature and temperature gradient of the battery. The resulting large temperature gradient would induce in-cell non-uniformity of charging-discharging current and state of health. Simply increasing the cooling intensity is inadequate to reduce the maximum temperature and narrow down the temperature difference due to the poor cross-plane thermal conductivity. Pulse charging protocol does not help to mitigate the temperature difference on the bias of same total charging time, because of larger time-averaged heat generation rate than constant current charging. Suggestions on battery geometry optimizations for both prismatic/pouch battery and cylindrical battery are proposed to reduce the maximum temperature and mitigate the temperature gradient within the lithium ion battery

  16. Modeling thermo-optic effect in large mode area double cladding photonic crystal fibers

    Science.gov (United States)

    Coscelli, Enrico; Cucinotta, Annamaria

    2014-02-01

    The impact of thermally-induced refractive index changes on the single-mode (SM) properties of large mode area (LMA) photonic crystal fibers are thoroughly investigated by means of a full-vector modal solver with integrated thermal model. Three photonic crystal fiber designs are taken into account, namely the 19-cell core fiber, the large-pitch fiber (LPF) and the distributed modal filtering (DMF) fiber, to assess the effects of the interplay between thermal effects and the high-order mode (HOM) suppression mechanisms exploited in order to obtain effectively SM guiding. The results have shown significant differences in the way the SM regime is changed by the increase of heat load, providing useful hints for the design of LMA fibers for high power lasers.

  17. Different goods, different effects: Exploring the effects of generalized social trust in large-N collective action

    DEFF Research Database (Denmark)

    Sønderskov, Kim Mannemar

    2009-01-01

    Does generalized social trust help solve large-N collective action problems? This paper argues so, offering a novel explanation for the relationship: People tend to cooperate if they expect others to be cooperating, which implies that people holding generalized social trust more readily cooperate...... in large-N dilemmas because they expect that most people will cooperate. The paper tests the explanation in a rigorous design. The analyses show a positive, robust effect of generalized social trust on public good provision, but no effect is found in a joint product situation. This supports the hypothesis......, indicating that trust specifically enhances cooperation in collective action dilemmas....

  18. Extremely Large Magnetoresistance at Low Magnetic Field by Coupling the Nonlinear Transport Effect and the Anomalous Hall Effect.

    Science.gov (United States)

    Luo, Zhaochu; Xiong, Chengyue; Zhang, Xu; Guo, Zhen-Gang; Cai, Jianwang; Zhang, Xiaozhong

    2016-04-13

    The anomalous Hall effect of a magnetic material is coupled to the nonlinear transport effect of a semiconductor material in a simple structure to achieve a large geometric magnetoresistance (MR) based on a diode-assisted mechanism. An extremely large MR (>10(4) %) at low magnetic fields (1 mT) is observed at room temperature. This MR device shows potential for use as a logic gate for the four basic Boolean logic operations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Renormalization-group flow of the effective action of cosmological large-scale structures

    CERN Document Server

    Floerchinger, Stefan

    2017-01-01

    Following an approach of Matarrese and Pietroni, we derive the functional renormalization group (RG) flow of the effective action of cosmological large-scale structures. Perturbative solutions of this RG flow equation are shown to be consistent with standard cosmological perturbation theory. Non-perturbative approximate solutions can be obtained by truncating the a priori infinite set of possible effective actions to a finite subspace. Using for the truncated effective action a form dictated by dissipative fluid dynamics, we derive RG flow equations for the scale dependence of the effective viscosity and sound velocity of non-interacting dark matter, and we solve them numerically. Physically, the effective viscosity and sound velocity account for the interactions of long-wavelength fluctuations with the spectrum of smaller-scale perturbations. We find that the RG flow exhibits an attractor behaviour in the IR that significantly reduces the dependence of the effective viscosity and sound velocity on the input ...

  20. Relativistic effects on large amplitude nonlinear Langmuir waves in a two-fluid plasma

    International Nuclear Information System (INIS)

    Nejoh, Yasunori

    1994-07-01

    Large amplitude relativistic nonlinear Langmuir waves are analyzed by the pseudo-potential method. The existence conditions for nonlinear Langmuir waves are confirmed by considering relativistic high-speed electrons in a two-fluid plasma. The significant feature of this investigation is that the propagation of nonlinear Langmuir waves depends on the ratio of the electron streaming velocity to the velocity of light, the normalized potential and the ion mass to electron mass ratio. The constant energy is determined by the specific range of the relativistic effect. In the non-relativistic limit, large amplitude relativistic Langmuir waves do not exist. The present investigation predicts new findings of large amplitude nonlinear Langmuir waves in space plasma phenomena in which relativistic electrons are important. (author)

  1. Large-current-controllable carbon nanotube field-effect transistor in electrolyte solution

    Science.gov (United States)

    Myodo, Miho; Inaba, Masafumi; Ohara, Kazuyoshi; Kato, Ryogo; Kobayashi, Mikinori; Hirano, Yu; Suzuki, Kazuma; Kawarada, Hiroshi

    2015-05-01

    Large-current-controllable carbon nanotube field-effect transistors (CNT-FETs) were fabricated with mm-long CNT sheets. The sheets, synthesized by remote-plasma-enhanced CVD, contained both single- and double-walled CNTs. Titanium was deposited on the sheet as source and drain electrodes, and an electrolyte solution was used as a gate electrode (solution gate) to apply a gate voltage to the CNTs through electric double layers formed around the CNTs. The drain current came to be well modulated as electrolyte solution penetrated into the sheets, and one of the solution gate CNT-FETs was able to control a large current of over 2.5 A. In addition, we determined the transconductance parameter per tube and compared it with values for other CNT-FETs. The potential of CNT sheets for applications requiring the control of large current is exhibited in this study.

  2. Performance of informative priors skeptical of large treatment effects in clinical trials: A simulation study.

    Science.gov (United States)

    Pedroza, Claudia; Han, Weilu; Thanh Truong, Van Thi; Green, Charles; Tyson, Jon E

    2018-01-01

    One of the main advantages of Bayesian analyses of clinical trials is their ability to formally incorporate skepticism about large treatment effects through the use of informative priors. We conducted a simulation study to assess the performance of informative normal, Student- t, and beta distributions in estimating relative risk (RR) or odds ratio (OR) for binary outcomes. Simulation scenarios varied the prior standard deviation (SD; level of skepticism of large treatment effects), outcome rate in the control group, true treatment effect, and sample size. We compared the priors with regards to bias, mean squared error (MSE), and coverage of 95% credible intervals. Simulation results show that the prior SD influenced the posterior to a greater degree than the particular distributional form of the prior. For RR, priors with a 95% interval of 0.50-2.0 performed well in terms of bias, MSE, and coverage under most scenarios. For OR, priors with a wider 95% interval of 0.23-4.35 had good performance. We recommend the use of informative priors that exclude implausibly large treatment effects in analyses of clinical trials, particularly for major outcomes such as mortality.

  3. Initial condition effects on large scale structure in numerical simulations of plane mixing layers

    Science.gov (United States)

    McMullan, W. A.; Garrett, S. J.

    2016-01-01

    In this paper, Large Eddy Simulations are performed on the spatially developing plane turbulent mixing layer. The simulated mixing layers originate from initially laminar conditions. The focus of this research is on the effect of the nature of the imposed fluctuations on the large-scale spanwise and streamwise structures in the flow. Two simulations are performed; one with low-level three-dimensional inflow fluctuations obtained from pseudo-random numbers, the other with physically correlated fluctuations of the same magnitude obtained from an inflow generation technique. Where white-noise fluctuations provide the inflow disturbances, no spatially stationary streamwise vortex structure is observed, and the large-scale spanwise turbulent vortical structures grow continuously and linearly. These structures are observed to have a three-dimensional internal geometry with branches and dislocations. Where physically correlated provide the inflow disturbances a "streaky" streamwise structure that is spatially stationary is observed, with the large-scale turbulent vortical structures growing with the square-root of time. These large-scale structures are quasi-two-dimensional, on top of which the secondary structure rides. The simulation results are discussed in the context of the varying interpretations of mixing layer growth that have been postulated. Recommendations are made concerning the data required from experiments in order to produce accurate numerical simulation recreations of real flows.

  4. Solar-terrestrial effect controls seismic activity to a large extent (Invited)

    Science.gov (United States)

    Duma, G.

    2010-12-01

    , too, and the number of events during Kp maxima is about twice that observed for N-America. For the whole of Eurasia the same becomes evident. In all three regions, the strongest earthquakes with magnitude 7 and even 8 occur during the Kp maxima. In the recent decade, several geophysical models have been tested to interpret the coupling between the solar induced geomagnetic variations and disturbances and its mechanic implications in the Earth’s lithosphere, i.e. in rupture zones. The main questions in that regard are, of course, how mechanic forces are generated by the magnetic variations and whether they are strong enough to influence the tectonic process, that is, to act as a powerful trigger mechanism, as observed. Two such models are demonstrated, which fit well the observations, and which both indicate a surprisingly high energy and mechanic stress involved in the process. They build on Lorentz forces and on the effect of magnetostriction, respectively. The effect applies in particular to strong earthquake activity as outlined above. Moreover, it is a general geodynamic process which acts in nearly all main seismic regions on the globe. Thus, the results add very novel and important aspects to the research on seismic performance, temporal trends of strong earthquake occurrence and hazard assessment.

  5. Influence of the large-small split effect on strategy choice in complex subtraction.

    Science.gov (United States)

    Xiang, Yan Hui; Wu, Hao; Shang, Rui Hong; Chao, Xiaomei; Ren, Ting Ting; Zheng, Li Ling; Mo, Lei

    2018-04-01

    Two main theories have been used to explain the arithmetic split effect: decision-making process theory and strategy choice theory. Using the inequality paradigm, previous studies have confirmed that individuals tend to adopt a plausibility-checking strategy and a whole-calculation strategy to solve large and small split problems in complex addition arithmetic, respectively. This supports strategy choice theory, but it is unknown whether this theory also explains performance in solving different split problems in complex subtraction arithmetic. This study used small, intermediate and large split sizes, with each split condition being further divided into problems requiring and not requiring borrowing. The reaction times (RTs) for large and intermediate splits were significantly shorter than those for small splits, while accuracy was significantly higher for large and middle splits than for small splits, reflecting no speed-accuracy trade-off. Further, RTs and accuracy differed significantly between the borrow and no-borrow conditions only for small splits. This study indicates that strategy choice theory is suitable to explain the split effect in complex subtraction arithmetic. That is, individuals tend to choose the plausibility-checking strategy or the whole-calculation strategy according to the split size. © 2016 International Union of Psychological Science.

  6. Characterizing Android apps’ behavior for effective detection of malapps at large scale

    KAUST Repository

    Wang, Xing

    2017-05-06

    Android malicious applications (malapps) have surged and been sophisticated, posing a great threat to users. How to characterize, understand and detect Android malapps at a large scale is thus a big challenge. In this work, we are motivated to discover the discriminatory and persistent features extracted from Android APK files for automated malapp detection at a large scale. To achieve this goal, firstly we extract a very large number of features from each app and categorize the features into two groups, namely, app-specific features as well as platform-defined features. These feature sets will then be fed into four classifiers (i.e., Logistic Regression, linear SVM, Decision Tree and Random Forest) for the detection of malapps. Secondly, we evaluate the persistence of app-specific and platform-defined features on classification performance with two data sets collected in different time periods. Thirdly, we comprehensively analyze the relevant features selected by Logistic Regression classifier to identify the contributions of each feature set. We conduct extensive experiments on large real-world app sets consisting of 213,256 benign apps collected from six app markets, 4,363 benign apps from Google Play market, and 18,363 malapps. The experimental results and our analysis give insights regarding what discriminatory features are most effective to characterize malapps for building an effective and efficient malapp detection system. With the selected discriminatory features, the Logistic Regression classifier yields the best true positive rate as 96% with a false positive rate as 0.06%.

  7. Derivation of the pure Faraday and Cotton-Mouton effects when polarimetric effects in a tokamak are large

    International Nuclear Information System (INIS)

    Segre, S E; Zanza, V

    2006-01-01

    When polarimetric effects are large the Cotton-Mouton and Faraday effects do not combine linearly and it is not possible to separate exactly the pure Cotton-Mouton effect W 1 and the pure Faraday effect, W 3 . Four alternative approximate expressions for W 1 and W 3 in terms of measurable quantities are examined for tokamak configurations. Two of these approximations proposed recently are found to be preferable, some previous statements concerning them are corrected and the errors incurred by their use are evaluated

  8. A hard-to-read font reduces the framing effect in a large sample.

    Science.gov (United States)

    Korn, Christoph W; Ries, Juliane; Schalk, Lennart; Oganian, Yulia; Saalbach, Henrik

    2018-04-01

    How can apparent decision biases, such as the framing effect, be reduced? Intriguing findings within recent years indicate that foreign language settings reduce framing effects, which has been explained in terms of deeper cognitive processing. Because hard-to-read fonts have been argued to trigger deeper cognitive processing, so-called cognitive disfluency, we tested whether hard-to-read fonts reduce framing effects. We found no reliable evidence for an effect of hard-to-read fonts on four framing scenarios in a laboratory (final N = 158) and an online study (N = 271). However, in a preregistered online study with a rather large sample (N = 732), a hard-to-read font reduced the framing effect in the classic "Asian disease" scenario (in a one-sided test). This suggests that hard-read-fonts can modulate decision biases-albeit with rather small effect sizes. Overall, our findings stress the importance of large samples for the reliability and replicability of modulations of decision biases.

  9. Reionization on large scales. IV. Predictions for the 21 cm signal incorporating the light cone effect

    Energy Technology Data Exchange (ETDEWEB)

    La Plante, P.; Battaglia, N.; Natarajan, A.; Peterson, J. B.; Trac, H. [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Cen, R. [Department of Astrophysical Science, Princeton University, Princeton, NJ 08544 (United States); Loeb, A., E-mail: plaplant@andrew.cmu.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2014-07-01

    We present predictions for the 21 cm brightness temperature power spectrum during the Epoch of Reionization (EoR). We discuss the implications of the 'light cone' effect, which incorporates evolution of the neutral hydrogen fraction and 21 cm brightness temperature along the line of sight. Using a novel method calibrated against radiation-hydrodynamic simulations, we model the neutral hydrogen density field and 21 cm signal in large volumes (L = 2 Gpc h {sup –1}). The inclusion of the light cone effect leads to a relative decrease of about 50% in the 21 cm power spectrum on all scales. We also find that the effect is more prominent at the midpoint of reionization and later. The light cone effect can also introduce an anisotropy along the line of sight. By decomposing the 3D power spectrum into components perpendicular to and along the line of sight, we find that in our fiducial reionization model, there is no significant anisotropy. However, parallel modes can contribute up to 40% more power for shorter reionization scenarios. The scales on which the light cone effect is relevant are comparable to scales where one measures the baryon acoustic oscillation. We argue that due to its large comoving scale and introduction of anisotropy, the light cone effect is important when considering redshift space distortions and future application to the Alcock-Paczyński test for the determination of cosmological parameters.

  10. An innovative large scale integration of silicon nanowire-based field effect transistors

    Science.gov (United States)

    Legallais, M.; Nguyen, T. T. T.; Mouis, M.; Salem, B.; Robin, E.; Chenevier, P.; Ternon, C.

    2018-05-01

    Since the early 2000s, silicon nanowire field effect transistors are emerging as ultrasensitive biosensors while offering label-free, portable and rapid detection. Nevertheless, their large scale production remains an ongoing challenge due to time consuming, complex and costly technology. In order to bypass these issues, we report here on the first integration of silicon nanowire networks, called nanonet, into long channel field effect transistors using standard microelectronic process. A special attention is paid to the silicidation of the contacts which involved a large number of SiNWs. The electrical characteristics of these FETs constituted by randomly oriented silicon nanowires are also studied. Compatible integration on the back-end of CMOS readout and promising electrical performances open new opportunities for sensing applications.

  11. Large radiative corrections to the effective potential and the gauge hierarchy problem

    International Nuclear Information System (INIS)

    Sachrajda, C.T.C.

    1982-01-01

    We study the higher order corrections to the effective potential in a simple toy model and in the SU(5) grand unified theory, with a view to seeing what their effects are on the stability equations, and hence on the gauge hierarchy problem for these theories. These corrections contain powers of log (v 2 /h 2 ), where v and h are the large and small vacuum expectation values respectively, and hence cannot a priori be neglected. Nevertheless, after summing these large logarithms we find that the stability equations always contain two equations for v (i.e. these equations are independent of h) and hence can only be satisfied by a special (and hence unnatural) choice of parameters. This we claim is the precise statement of the gauge hierarchy problem. (orig.)

  12. Decrease of the tunneling time and violation of the Hartman effect for large barriers

    International Nuclear Information System (INIS)

    Olkhovsky, V.S.; Zaichenko, A.K.; Petrillo, V.

    2004-01-01

    The explicit formulation of the initial conditions of the definition of the wave-packet tunneling time is proposed. This formulation takes adequately into account the irreversibility of the wave-packet space-time spreading. Moreover, it explains the violations of the Hartman effect, leading to a strong decrease of the tunneling times up to negative values for wave packets with large momentum spreads due to strong wave-packet time spreading

  13. Test methods of total dose effects in very large scale integrated circuits

    International Nuclear Information System (INIS)

    He Chaohui; Geng Bin; He Baoping; Yao Yujuan; Li Yonghong; Peng Honglun; Lin Dongsheng; Zhou Hui; Chen Yusheng

    2004-01-01

    A kind of test method of total dose effects (TDE) is presented for very large scale integrated circuits (VLSI). The consumption current of devices is measured while function parameters of devices (or circuits) are measured. Then the relation between data errors and consumption current can be analyzed and mechanism of TDE in VLSI can be proposed. Experimental results of 60 Co γ TDEs are given for SRAMs, EEPROMs, FLASH ROMs and a kind of CPU

  14. Do Large Companies Have Lower Effective Corporate Tax Rates? A European Survey

    OpenAIRE

    Gaëtan Nicodème

    2007-01-01

    The current debate in corporate taxation is focusing on leveling the tax playing field within the European Union for companies operating across-countries. However, tax burdens could also vary with the size of companies within the same country, raising the question whether large companies pay their share of the burden. This paper uses firm-level data for 21 European countries between 1992 and 2004. The paper finds a robust negative correlation between the number of employees and the effective ...

  15. Examining the effectiveness of experiential teaching in small and large OM modules

    OpenAIRE

    Piercy, N.; Brandon-Jones, A.; Brandon-Jones, E.; Campbell, C.

    2012-01-01

    Purpose – This paper aims to examine the preferences of students towards different teaching methods and the perceived effectiveness of experiential teaching methods in different operations management (OM) modules.Design/methodology/approach – Student perceptions of different teaching methods and various aspects of an experiential teaching method, in the form of a business simulation game, are examined using survey data from 274 respondents in four small post-experience and two large pre-exper...

  16. The effects of an invasive alien plant (Chromolaena odorata on large African mammals

    Directory of Open Access Journals (Sweden)

    Lihle Dumalisile

    2017-11-01

    Full Text Available Alien plants have invaded most ecosystem types (terrestrial, fresh water and marine and are responsible for the loss of irreplaceable natural services on which humankind relies. They alter food quantity, quality and accessibility, and may result in declines in native species richness, which may ultimately result in extinction. For an effective management of invasive alien plants, it is important to understand the effects that such plants have on all levels of biodiversity. However, the effects that invasive alien plants, such as the Triffid weed (Chromolaena odorata, have on mammalian biodiversity, especially large mammalian species, are not well-known, although they play major ecological roles in areas such as nutrient cycling. Also, little is known about the recovery of the ecosystem following alien plant removal. This study investigated the effects of C. odorata invasion on large mammalian herbivores in Hluhluwe-iMfolozi Park and whether clearing of this plant helped in rehabilitating the habitat. We used track counts to estimate and compare species richness, diversity and abundance indices for large mammalian species between areas with differing C. odorata invasion durations (ca 2 years, ca 10 years, ca 20 years, areas with differing clearing times (cl < 2 years, cl 3–5 years and an area without any history of C. odorata invasion as a control. The results from this study show that large mammalian species utilised the uninvaded and the cleared areas more than the invaded areas. Species richness, abundance and diversity decreased with increasing invasion duration and cleared areas showed an increasing species richness and abundance. We conclude that this invasive alien plant modifies habitats and their removal does aid in the restoration of the ecosystem.

  17. The effects of large scale processing on caesium leaching from cemented simulant sodium nitrate waste

    International Nuclear Information System (INIS)

    Lee, D.J.; Brown, D.J.

    1982-01-01

    The effects of large scale processing on the properties of cemented simulant sodium nitrate waste have been investigated. Leach tests have been performed on full-size drums, cores and laboratory samples of cement formulations containing Ordinary Portland Cement (OPC), Sulphate Resisting Portland Cement (SRPC) and a blended cement (90% ground granulated blast furnace slag/10% OPC). In addition, development of the cement hydration exotherms with time and the temperature distribution in 220 dm 3 samples have been followed. (author)

  18. Effectiveness of Acupuncture Therapy on Stress in a Large Urban College Population.

    Science.gov (United States)

    Schroeder, Stefanie; Burnis, James; Denton, Antony; Krasnow, Aaron; Raghu, T S; Mathis, Kimberly

    2017-06-01

    This study is a randomized controlled clinical trial to study the effectiveness of acupuncture on the perception of stress in patients who study or work on a large, urban college campus. The hypothesis was that verum acupuncture would demonstrate a significant positive impact on perceived stress as compared to sham acupuncture. This study included 111 participants with high self-reported stress levels who either studied or worked at a large, urban public university in the southwestern United States. However, only 62 participants completed the study. The participants were randomized into a verum acupuncture or sham acupuncture group. Both the groups received treatment once a week for 12 weeks. The Cohen's global measure of perceived stress scale (PSS-14) was completed by each participant prior to treatment, at 6 weeks, at 12 weeks, and 6 weeks and 12 weeks post-treatment completion. While participants of both the groups showed a substantial initial decrease in perceived stress scores, at 12 weeks post treatment, the verum acupuncture group showed a significantly greater treatment effect than the sham acupuncture group. This study indicates that acupuncture may be successful in decreasing the perception of stress in students and staff at a large urban university, and this effect persists for at least 3 months after the completion of treatment. Copyright © 2017. Published by Elsevier B.V.

  19. A large-scale deforestation experiment: Effects of patch area and isolation on Amazon birds

    Science.gov (United States)

    Ferraz, G.; Nichols, J.D.; Hines, J.E.; Stouffer, P.C.; Bierregaard, R.O.; Lovejoy, T.E.

    2007-01-01

    As compared with extensive contiguous areas, small isolated habitat patches lack many species. Some species disappear after isolation; others are rarely found in any small patch, regardless of isolation. We used a 13-year data set of bird captures from a large landscape-manipulation experiment in a Brazilian Amazon forest to model the extinction-colonization dynamics of 55 species and tested basic predictions of island biogeography and metapopulation theory. From our models, we derived two metrics of species vulnerability to changes in isolation and patch area. We found a strong effect of area and a variable effect of isolation on the predicted patch occupancy by birds.

  20. Effective Conformal Descriptions of Black Hole Entropy

    Directory of Open Access Journals (Sweden)

    Steven Carlip

    2011-07-01

    Full Text Available It is no longer considered surprising that black holes have temperatures and entropies. What remains surprising, though, is the universality of these thermodynamic properties: their exceptionally simple and general form, and the fact that they can be derived from many very different descriptions of the underlying microscopic degrees of freedom. I review the proposal that this universality arises from an approximate conformal symmetry, which permits an effective “conformal dual” description that is largely independent of the microscopic details.

  1. Cluster galaxy dynamics and the effects of large-scale environment

    Science.gov (United States)

    White, Martin; Cohn, J. D.; Smit, Renske

    2010-11-01

    Advances in observational capabilities have ushered in a new era of multi-wavelength, multi-physics probes of galaxy clusters and ambitious surveys are compiling large samples of cluster candidates selected in different ways. We use a high-resolution N-body simulation to study how the influence of large-scale structure in and around clusters causes correlated signals in different physical probes and discuss some implications this has for multi-physics probes of clusters (e.g. richness, lensing, Compton distortion and velocity dispersion). We pay particular attention to velocity dispersions, matching galaxies to subhaloes which are explicitly tracked in the simulation. We find that not only do haloes persist as subhaloes when they fall into a larger host, but groups of subhaloes retain their identity for long periods within larger host haloes. The highly anisotropic nature of infall into massive clusters, and their triaxiality, translates into an anisotropic velocity ellipsoid: line-of-sight galaxy velocity dispersions for any individual halo show large variance depending on viewing angle. The orientation of the velocity ellipsoid is correlated with the large-scale structure, and thus velocity outliers correlate with outliers caused by projection in other probes. We quantify this orientation uncertainty and give illustrative examples. Such a large variance suggests that velocity dispersion estimators will work better in an ensemble sense than for any individual cluster, which may inform strategies for obtaining redshifts of cluster members. We similarly find that the ability of substructure indicators to find kinematic substructures is highly viewing angle dependent. While groups of subhaloes which merge with a larger host halo can retain their identity for many Gyr, they are only sporadically picked up by substructure indicators. We discuss the effects of correlated scatter on scaling relations estimated through stacking, both analytically and in the simulations

  2. Effects of large deep-seated landslides on hillslope morphology, western Southern Alps, New Zealand

    Science.gov (United States)

    Korup, Oliver

    2006-03-01

    Morphometric analysis and air photo interpretation highlight geomorphic imprints of large landslides (i.e., affecting ≥1 km2) on hillslopes in the western Southern Alps (WSA), New Zealand. Large landslides attain kilometer-scale runout, affect >50% of total basin relief, and in 70% are slope clearing, and thus relief limiting. Landslide terrain shows lower mean local relief, relief variability, slope angles, steepness, and concavity than surrounding terrain. Measuring mean slope angle smoothes out local landslide morphology, masking any relationship between large landslides and possible threshold hillslopes. Large failures also occurred on low-gradient slopes, indicating persistent low-frequency/high-magnitude hillslope adjustment independent of fluvial bedrock incision. At the basin and hillslope scale, slope-area plots partly constrain the effects of landslides on geomorphic process regimes. Landslide imprints gradually blend with relief characteristics at orogen scale (102 km), while being sensitive to length scales of slope failure, topography, sampling, and digital elevation model resolution. This limits means of automated detection, and underlines the importance of local morphologic contrasts for detecting large landslides in the WSA. Landslide controls on low-order drainage include divide lowering and shifting, formation of headwater basins and hanging valleys, and stream piracy. Volumes typically mobilized, yet still stored in numerous deposits despite high denudation rates, are >107 m3, and theoretically equal to 102 years of basin-wide debris production from historic shallow landslides; lack of absolute ages precludes further estimates. Deposit size and mature forest cover indicate residence times of 101-104 years. On these timescales, large landslides require further attention in landscape evolution models of tectonically active orogens.

  3. Projection Effects of Large-scale Structures on Weak-lensing Peak Abundances

    Science.gov (United States)

    Yuan, Shuo; Liu, Xiangkun; Pan, Chuzhong; Wang, Qiao; Fan, Zuhui

    2018-04-01

    High peaks in weak lensing (WL) maps originate dominantly from the lensing effects of single massive halos. Their abundance is therefore closely related to the halo mass function and thus a powerful cosmological probe. However, besides individual massive halos, large-scale structures (LSS) along lines of sight also contribute to the peak signals. In this paper, with ray-tracing simulations, we investigate the LSS projection effects. We show that for current surveys with a large shape noise, the stochastic LSS effects are subdominant. For future WL surveys with source galaxies having a median redshift z med ∼ 1 or higher, however, they are significant. For the cosmological constraints derived from observed WL high-peak counts, severe biases can occur if the LSS effects are not taken into account properly. We extend the model of Fan et al. by incorporating the LSS projection effects into the theoretical considerations. By comparing with simulation results, we demonstrate the good performance of the improved model and its applicability in cosmological studies.

  4. Comparison of cardioprotective effects of salvianolic acid B and benazepril on large myocardial infarction in rats.

    Science.gov (United States)

    He, Hai-Bo; Yang, Xian-Zhe; Shi, Meng-Qiong; Zeng, Xiao-Wei; Wu, Li-Mao; Li, Lian-Da

    2008-01-01

    In the present study, we compared cardioprotective effects of salvianolic acid B (Sal B) and the angiotension-converting enzyme inhibitor, benazepril, in rats with large myocardial infarction (MI). The large MI was produced by coronary artery ligation for 4 weeks in rats. The rats were divided into the following groups: sham operation; MI; MI + Sal B (100 mg/kg by a gavage, once a day for 4 weeks) and MI + benazepril (1 mg/kg by a gavage, once a day for 4 weeks). Echocardiogram, hemodynamic and hemorheological changes, angiogenesis, infarct size and cardiac remodeling, as well as messenger ribonucleic acid (mRNA) of vascular endothelium growth factor (VEGF) were measured. The following similar effects were observed in MI rats treated with Sal B and benazepril: (1) a marked improvement of echocardiographic, hemodynamic and hemorheological parameters, (2) significant reduction of infarct size, (3) significantly attenuated heart hypertrophy, left ventricular (LV) dilatation and fibrosis. The unique effects of Sal B were: angiogenesis and augmented VEGF expression in the border and remote noninfarcted LV area. These results suggest that Sal B and benazepril exerted beneficial cardioprotective effects. However, Sal B enforced some different modality than benazepril, which might improve myocardial microcirculation by augmenting VEGF expression and promoting angiogenesis besides similar effects to benazepril.

  5. [Adverse Effect Predictions Based on Computational Toxicology Techniques and Large-scale Databases].

    Science.gov (United States)

    Uesawa, Yoshihiro

    2018-01-01

     Understanding the features of chemical structures related to the adverse effects of drugs is useful for identifying potential adverse effects of new drugs. This can be based on the limited information available from post-marketing surveillance, assessment of the potential toxicities of metabolites and illegal drugs with unclear characteristics, screening of lead compounds at the drug discovery stage, and identification of leads for the discovery of new pharmacological mechanisms. This present paper describes techniques used in computational toxicology to investigate the content of large-scale spontaneous report databases of adverse effects, and it is illustrated with examples. Furthermore, volcano plotting, a new visualization method for clarifying the relationships between drugs and adverse effects via comprehensive analyses, will be introduced. These analyses may produce a great amount of data that can be applied to drug repositioning.

  6. Design of an amplifier model accounting for thermal effect in fully aperiodic large pitch fibers

    Science.gov (United States)

    Tragni, K.; Molardi, C.; Poli, F.; Dauliat, R.; Leconte, B.; Darwich, D.; du Jeu, R.; Malleville, M. A.; Jamier, R.; Selleri, S.; Roy, P.; Cucinotta, A.

    2018-02-01

    Yb-doped Photonic Crystal Fibers (PCFs) have triggered a significant power scaling into fiber-based lasers. However thermally-induced effects, like mode instability, can compromise the output beam quality. PCF design with improved Higher Order Mode (HOM) delocalization and effective thermal resilience can contain the problem. In particular, Fully- Aperiodic Large-Pitch Fibers (FA-LPFs) have shown interesting properties in terms of resilience to thermal effects. In this paper the performances of a Yb-doped FA-LPF amplifier are experimentally and numerically investigated. Modal properties and gain competition between Fundamental Mode (FM) and first HOM have been calculated, in presence of thermal effects. The main doped fiber characteristics have been derived by comparison between experimental and numerical results.

  7. Prediction, Expectation, and Surprise: Methods, Designs, and Study of a Deployed Traffic Forecasting Service

    OpenAIRE

    Horvitz, Eric J.; Apacible, Johnson; Sarin, Raman; Liao, Lin

    2012-01-01

    We present research on developing models that forecast traffic flow and congestion in the Greater Seattle area. The research has led to the deployment of a service named JamBayes, that is being actively used by over 2,500 users via smartphones and desktop versions of the system. We review the modeling effort and describe experiments probing the predictive accuracy of the models. Finally, we present research on building models that can identify current and future surprises, via efforts on mode...

  8. Analysis of physiological signals for recognition of boredom, pain, and surprise emotions.

    Science.gov (United States)

    Jang, Eun-Hye; Park, Byoung-Jun; Park, Mi-Sook; Kim, Sang-Hyeob; Sohn, Jin-Hun

    2015-06-18

    The aim of the study was to examine the differences of boredom, pain, and surprise. In addition to that, it was conducted to propose approaches for emotion recognition based on physiological signals. Three emotions, boredom, pain, and surprise, are induced through the presentation of emotional stimuli and electrocardiography (ECG), electrodermal activity (EDA), skin temperature (SKT), and photoplethysmography (PPG) as physiological signals are measured to collect a dataset from 217 participants when experiencing the emotions. Twenty-seven physiological features are extracted from the signals to classify the three emotions. The discriminant function analysis (DFA) as a statistical method, and five machine learning algorithms (linear discriminant analysis (LDA), classification and regression trees (CART), self-organizing map (SOM), Naïve Bayes algorithm, and support vector machine (SVM)) are used for classifying the emotions. The result shows that the difference of physiological responses among emotions is significant in heart rate (HR), skin conductance level (SCL), skin conductance response (SCR), mean skin temperature (meanSKT), blood volume pulse (BVP), and pulse transit time (PTT), and the highest recognition accuracy of 84.7% is obtained by using DFA. This study demonstrates the differences of boredom, pain, and surprise and the best emotion recognizer for the classification of the three emotions by using physiological signals.

  9. The effects of Strongylus vulgaris parasitism on eosinophil distribution and accumulation in equine large intestinal mucosa.

    Science.gov (United States)

    Rötting, A K; Freeman, D E; Constable, P D; Moore, R M; Eurell, J C; Wallig, M A; Hubert, J D

    2008-06-01

    Eosinophilic granulocytes have been associated with parasite or immune-mediated diseases, but their functions in other disease processes remain unclear. Cause and timing of eosinophil migration into the equine gastrointestinal mucosa are also unknown. To determine the effects of intestinal parasitism on eosinophils in equine large intestinal mucosa. Large intestinal mucosal samples were collected from horses and ponies (n = 16) from the general veterinary hospital population, ponies (n = 3) raised in a parasite-free environment, ponies experimentally infected with 500 infective Strongylus vulgaris larvae and treated with a proprietary anthelmintic drug (n = 14), and a similar group of ponies (n = 7) that received no anthelmintic treatment. Total eosinophil counts and eosinophil distribution in the mucosa were determined by histological examination. A mixed model analysis was performed and appropriate Bonferroni adjusted P values used for each family of comparisons. Pvulgaris and those raised in a parasite-free environment. Experimental infection with S. vulgaris, with or without subsequent anthelmintic treatment, did not change eosinophil counts, and counts were similar to those for horses from the general population. Migration of eosinophils to the equine large intestinal mucosa appears to be independent of exposure to parasites. Large intestinal mucosal eosinophils may have more functions in addition to their role in defence against parasites.

  10. Electromagnetic and structural coupled analysis with the effect of large deflection

    International Nuclear Information System (INIS)

    Horie, Tomoyoshi; Niho, Tomoya

    1997-01-01

    In the designs of future fusion reactors and magnetic levitated vehicles, thin shell conducting structures are located in a high electromagnetic field. The transient magnetic field induces the eddy current on the conductive structure. While the Lorentz force by the eddy current and the magnetic field is loaded to the thin shell structure, the electromotive force by the deflection velocity and magnetic field reduces the eddy current. Therefore, the electromagnetic and structural coupled analysis is required for the design of these components. This paper describes a coupled finite element analysis for the eddy current and the structure. A formulation is presented considering the effect of the large deflection of shell structures by the total Lagrangian formulation. Both matrix equations for the eddy current and the structure are solved simultaneously using coupling sub-matrices. A coupled problem of a cantilever bending plate is analyzed. Based on the analysis results, the influence of the large deflection on the coupling effect is discussed. The condition that the large deflection analysis is required is examined through some parametric analyses

  11. Simultaneous effect of modified gravity and primordial non-Gaussianity in large scale structure observations

    International Nuclear Information System (INIS)

    Mirzatuny, Nareg; Khosravi, Shahram; Baghram, Shant; Moshafi, Hossein

    2014-01-01

    In this work we study the simultaneous effect of primordial non-Gaussianity and the modification of the gravity in f(R) framework on large scale structure observations. We show that non-Gaussianity and modified gravity introduce a scale dependent bias and growth rate functions. The deviation from ΛCDM in the case of primordial non-Gaussian models is in large scales, while the growth rate deviates from ΛCDM in small scales for modified gravity theories. We show that the redshift space distortion can be used to distinguish positive and negative f NL in standard background, while in f(R) theories they are not easily distinguishable. The galaxy power spectrum is generally enhanced in presence of non-Gaussianity and modified gravity. We also obtain the scale dependence of this enhancement. Finally we define galaxy growth rate and galaxy growth rate bias as new observational parameters to constrain cosmology

  12. Large photon drag effect of intrinsic graphene induced by plasmonic evanescent field

    Science.gov (United States)

    Luo, Ma; Li, Zhibing

    2016-12-01

    A large photon drag effect of the massless Dirac fermions in intrinsic graphene is predicted for a graphene-on-plasmonic-layer system. The surface plasmons in the plasmonic layer enlarge the wave number of the photon hundreds times more than in vacuum. The evanescent field of the surface plasmons generates a directional motion of carriers in the intrinsic graphene because of the large momentum transfer from the surface plasmon to the excited carriers. A model Hamiltonian is developed on the assumption that the in-plane wavelength of the surface plasmons is much smaller than the mean free path of the carriers. The time evolution of the density matrix is solved by perturbation method as well as numerical integration. The nondiagonal density matrix elements with momentum transfer lead to a gauge current, which is an optically driven macroscopic direct current. The dependence of the macroscopic direct current on the incident direction and intensity of the laser field is studied.

  13. Hydrologic effects of large southwestern USA wildfires significantly increase regional water supply: fact or fiction?

    Science.gov (United States)

    Wine, M. L.; Cadol, D.

    2016-08-01

    In recent years climate change and historic fire suppression have increased the frequency of large wildfires in the southwestern USA, motivating study of the hydrological consequences of these wildfires at point and watershed scales, typically over short periods of time. These studies have revealed that reduced soil infiltration capacity and reduced transpiration due to tree canopy combustion increase streamflow at the watershed scale. However, the degree to which these local increases in runoff propagate to larger scales—relevant to urban and agricultural water supply—remains largely unknown, particularly in semi-arid mountainous watersheds co-dominated by winter snowmelt and the North American monsoon. To address this question, we selected three New Mexico watersheds—the Jemez (1223 km2), Mogollon (191 km2), and Gila (4807 km2)—that together have been affected by over 100 wildfires since 1982. We then applied climate-driven linear models to test for effects of fire on streamflow metrics after controlling for climatic variability. Here we show that, after controlling for climatic and snowpack variability, significantly more streamflow discharged from the Gila watershed for three to five years following wildfires, consistent with increased regional water yield due to enhanced infiltration-excess overland flow and groundwater recharge at the large watershed scale. In contrast, we observed no such increase in discharge from the Jemez watershed following wildfires. Fire regimes represent a key difference between the contrasting responses of the Jemez and Gila watersheds with the latter experiencing more frequent wildfires, many caused by lightning strikes. While hydrologic dynamics at the scale of large watersheds were previously thought to be climatically dominated, these results suggest that if one fifth or more of a large watershed has been burned in the previous three to five years, significant increases in water yield can be expected.

  14. Implementation of effective alcohol control strategies is needed at large sports and entertainment events.

    Science.gov (United States)

    Lyne, Mark; Galloway, Andrew

    2012-02-01

    To assess the implementation and effectiveness of strategies and actions to eliminate and/or reduce alcohol-related problems at large sports and entertainment events in New Zealand. We conducted site visits and monitoring observations at venues before, during and after a variety of large events between March 2009 and November 2010. Thirteen events were attended at nine different venues. Events included rugby, rugby league and cricket matches, motor racing, rowing, horse racing, an outdoor music festival, and food and wine festivals. Most large events appeared to pass with few or no alcohol-related problems. The exceptions were one of the horse-race meetings, a rugby league match and one food and wine festival. Common contexts at events where alcohol-related problems were seen included: inadequate alcohol control and management by security staff; the ability to purchase four alcoholic drinks (rather than two) at a time; inexperienced bar staff untrained in responsible alcohol service; no or little promotion of low and non-alcoholic drinks; and a lack of monitoring and enforcement of the law on intoxication. An important approach to prevent and reduce alcohol-related problems at large spots and entertainment events is the use of specific alcohol-control strategies. The management of alcohol consumption is a major part of event management that must be planned with harm-minimisation strategies well in advance of the event itself. If strategies and actions are not properly implemented to manage the sale and supply of alcohol at large events, there is significant risk of alcohol-related problems and harm resulting from them. © 2012 The Authors. ANZJPH © 2012 Public Health Association of Australia.

  15. COMBINED EFFECTS OF GALAXY INTERACTIONS AND LARGE-SCALE ENVIRONMENT ON GALAXY PROPERTIES

    International Nuclear Information System (INIS)

    Park, Changbom; Choi, Yun-Young

    2009-01-01

    We inspect the coupled dependence of physical parameters of the Sloan Digital Sky Survey galaxies on the small-scale (distance to and morphology of the nearest neighbor galaxy) and the large-scale (background density smoothed over 20 nearby galaxies) environments. The impacts of interaction on galaxy properties are detected at least out to the neighbor separation corresponding to the virial radius of galaxies, which is typically between 200 and 400 h -1 kpc for the galaxies in our sample. To detect these long-range interaction effects, it is crucial to divide galaxy interactions into four cases dividing the morphology of target and neighbor galaxies into early and late types. We show that there are two characteristic neighbor-separation scales where the galaxy interactions cause abrupt changes in the properties of galaxies. The first scale is the virial radius of the nearest neighbor galaxy r vir,nei . Many physical parameters start to deviate from those of extremely isolated galaxies at the projected neighbor separation r p of about r vir,nei . The second scale is at r p ∼ 0.05r vir,nei = 10-20 h -1 kpc, and is the scale at which the galaxies in pairs start to merge. We find that late-type neighbors enhance the star formation activity of galaxies while early-type neighbors reduce it, and that these effects occur within r vir,nei . The hot halo gas and cold disk gas must be participating in the interactions at separations less than the virial radius of the galaxy plus dark halo system. Our results also show that the role of the large-scale density in determining galaxy properties is minimal once luminosity and morphology are fixed. We propose that the weak residual dependence of galaxy properties on the large-scale density is due to the dependence of the halo gas property on the large-scale density.

  16. The costs and effectiveness of large Phase III pre-licensure vaccine clinical trials.

    Science.gov (United States)

    Black, Steven

    2015-01-01

    Prior to the 1980s, most vaccines were licensed based upon safety and effectiveness studies in several hundred individuals. Beginning with the evaluation of Haemophilus influenzae type b conjugate vaccines, much larger pre-licensure trials became common. The pre-licensure trial for Haemophilus influenzae oligosaccharide conjugate vaccine had more than 60,000 children and that of the seven-valent pneumococcal conjugate vaccine included almost 38,000 children. Although trial sizes for both of these studies were driven by the sample size required to demonstrate efficacy, the sample size requirements for safety evaluations of other vaccines have subsequently increased. With the demonstration of an increased risk of intussusception following the Rotashield brand rotavirus vaccine, this trend has continued. However, routinely requiring safety studies of 20,000-50,000 or more participants has two major downsides. First, the cost of performing large safety trials routinely prior to licensure of a vaccine is very large, with some estimates as high at US$200 million euros for one vaccine. This high financial cost engenders an opportunity cost whereby the number of vaccines that a company is willing or able to develop to meet public health needs becomes limited by this financial barrier. The second downside is that in the pre-licensure setting, such studies are very time consuming and delay the availability of a beneficial vaccine substantially. One might argue that in some situations, this financial commitment is warranted such as for evaluations of the risk of intussusception following newer rotavirus vaccines. However, it must be noted that while an increased risk of intussusception was not identified in large pre-licensure studies, in post marketing evaluations an increased risk of this outcome has been identified. Thus, even the extensive pre-licensure evaluations conducted did not identify an associated risk. The limitations of large Phase III trials have also been

  17. Large Fizeau's light-dragging effect in a moving electromagnetically induced transparent medium.

    Science.gov (United States)

    Kuan, Pei-Chen; Huang, Chang; Chan, Wei Sheng; Kosen, Sandoko; Lan, Shau-Yu

    2016-10-03

    As one of the most influential experiments on the development of modern macroscopic theory from Newtonian mechanics to Einstein's special theory of relativity, the phenomenon of light dragging in a moving medium has been discussed and observed extensively in different types of systems. To have a significant dragging effect, the long duration of light travelling in the medium is preferred. Here we demonstrate a light-dragging experiment in an electromagnetically induced transparent cold atomic ensemble and enhance the dragging effect by at least three orders of magnitude compared with the previous experiments. With a large enhancement of the dragging effect, we realize an atom-based velocimeter that has a sensitivity two orders of magnitude higher than the velocity width of the atomic medium used. Such a demonstration could pave the way for motional sensing using the collective state of atoms in a room temperature vapour cell or solid state material.

  18. Climatological changing effects on wind, precipitation and erosion: Large, meso and small scale analysis

    International Nuclear Information System (INIS)

    Aslan, Z.

    2004-01-01

    The Fourier transformation analysis for monthly average values of meteorological parameters has been considered, and amplitudes, phase angles have been calculated by using ground measurements in Turkey. The first order harmonics of meteorological parameters show large scale effects, while higher order harmonics show the effects of small scale fluctuations. The variations of first through sixth order harmonic amplitudes and phases provide a useful means of understanding the large and local scale effects on meteorological parameters. The phase angle can be used to determine the time of year the maximum or minimum of a given harmonic occurs. The analysis helps us to distinguish different pressure, relative humidity, temperature, precipitation and wind speed regimes and transition regions. Local and large scale phenomenon and some unusual seasonal patterns are also defined near Keban Dam and the irrigation area. Analysis of precipitation based on long term data shows that semi-annual fluctuations are predominant in the study area. Similarly, pressure variations are mostly influenced by semi-annual fluctuations. Temperature and humidity variations are mostly influenced by meso and micro scale fluctuations. Many large and meso scale climate change simulations for the 21st century are based on concentration of green house gases. A better understanding of these effects on soil erosion is necessary to determine social, economic and other impacts of erosion. The second part of this study covers the time series analysis of precipitation, rainfall erosivity and wind erosion at the Marmara Region. Rainfall and runoff erosivity factors are defined by considering the results of field measurements at 10 stations. Climatological changing effects on rainfall erosion have been determined by monitoring meteorological variables. In the previous studies, Fournier Index is defined to estimate the rainfall erosivity for the study area. The Fournier Index or in other words a climatic index

  19. Need for new effect based on large-scale development of renewable energy in Northern Europe

    International Nuclear Information System (INIS)

    Doorman, Gerard; Grinden, Bjoern; Fuchs, Ida

    2007-02-01

    Changes in the effect balance in Northern Europe between 2005 and 2020 are evaluated. Norway, Denmark, Sweden, Finland, Germany and the Netherlands are the countries included in the analysis. Scenarios from studies conducted in the different countries have been used as starting points. Some scenarios give explicit figures for effect installations, but most only provide estimations on the energy balance. In these cased it has been necessary to estimate how much effect there is behind the energy figures. Utilization time analyses have been employed for this, primarily. Moreover, emphasis has been put on the modelling of wind power's effect contribution, and a method based on the reliability of the production system has been employed, giving an effect varying between 18 and 24 percent in the different scenarios. Also, the need for regulation reserves has been considered. Four scenarios have been outlined along the axes growth in consumption (high/low) and share of renewable energy (high/low). All scenarios show considerable reductions in the effect balance from 2005 to 2020, varying from about 15.000 MW to 22.000 MW. The largest reduction is in Germany, but Sweden too has large reductions in each of the scenarios. The most important underlying causes are the reduction or dismantling of nuclear power and the development of large amounts of wind power, and in Germany also the development of solar power. In Norway too, the effect balance is weakened with the existing scenarios. Here, wind power and small-scale hydroelectric power contribute with relatively much energy, but little effect. The biggest insecurity in the analysis is how much thermal capacity there will be in operation in 2020, especially in Germany. In a system with much wind power, the utilization time for some of the thermal production may be short, and it may be phased out if no support schemes for effect reserves are set up. Thermal capacity as short term backup for wind power will have to compete with

  20. D-brane black holes: Large-N limit and the effective string description

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, S F [International Centre for Theoretical Physics, Trieste (Italy); Wadia, S R [Theoretical Physics Div., CERN, Geneva (Switzerland)

    1997-03-01

    We address the derivation of the effective conformal field theory description of the 5-dimensional black hole, modelled by a collection of D1-and D5-branes, from the corresponding low energy U(Q{sub 1}) x U(Q{sub 5}) gauge theory. Finite horizon size at weak coupling requires both Q{sub 1} and Q{sub 5} to be large. We derive the results in the moduli space approximation (say for Q{sub 1} > Q{sub 5}) and appeal to supersymmetry to argue its validity beyond weak coupling. As a result of a combination of quenched Z{sub Q1} Wilson lines and a residual Weyl symmetry, the low-lying excitations of the U(Q{sub 1}) x U(Q{sub 5}) gauge theory are described by an effective N = 4 superconformal field theory with c = 6 in 1 + 1 dimensions, where the space is a circle of radius RQ{sub 1}Q{sub 5}. We also discuss the appearance of a marginal perturbation of the effective conformal field theory for large but finite values of Q{sub 5}. (author). 42 refs.

  1. THERAPEUTIC EFFECT OF SOLASODINE RHAMNOSYL GLYCOSIDES FOR LARGE SKIN CANCERS: TWO CLINICAL CASES

    Directory of Open Access Journals (Sweden)

    Bill E. Cham

    2012-01-01

    Full Text Available Solasodine rhamnosyl glycosides (BEC are a new class of antineoplastics, the efficiency of which administered via intravenous, intraperitoneal, and intratumoral routes is higher than that of many other antitumor agents. Early investigations have established the efficiency of topical BEC applications as a treatment option for non-melanoma skin cancers. There have recently been two clinical cases that count in favor of the fact that the cream formulation Curaderm containing BEC has a very high efficacy in the treatment of large non-melanoma skin cancers that are incurable by other existing methods. Also, Curaderm treatment shows a splendid cosmetic effect

  2. A Large Scale Test of the Effect of Social Class on Prosocial Behavior

    Science.gov (United States)

    Korndörfer, Martin; Egloff, Boris; Schmukle, Stefan C.

    2015-01-01

    Does being from a higher social class lead a person to engage in more or less prosocial behavior? Psychological research has recently provided support for a negative effect of social class on prosocial behavior. However, research outside the field of psychology has mainly found evidence for positive or u-shaped relations. In the present research, we therefore thoroughly examined the effect of social class on prosocial behavior. Moreover, we analyzed whether this effect was moderated by the kind of observed prosocial behavior, the observed country, and the measure of social class. Across eight studies with large and representative international samples, we predominantly found positive effects of social class on prosociality: Higher class individuals were more likely to make a charitable donation and contribute a higher percentage of their family income to charity (32,090 ≥ N ≥ 3,957; Studies 1–3), were more likely to volunteer (37,136 ≥N ≥ 3,964; Studies 4–6), were more helpful (N = 3,902; Study 7), and were more trusting and trustworthy in an economic game when interacting with a stranger (N = 1,421; Study 8) than lower social class individuals. Although the effects of social class varied somewhat across the kinds of prosocial behavior, countries, and measures of social class, under no condition did we find the negative effect that would have been expected on the basis of previous results reported in the psychological literature. Possible explanations for this divergence and implications are discussed. PMID:26193099

  3. A Large Scale Test of the Effect of Social Class on Prosocial Behavior.

    Science.gov (United States)

    Korndörfer, Martin; Egloff, Boris; Schmukle, Stefan C

    2015-01-01

    Does being from a higher social class lead a person to engage in more or less prosocial behavior? Psychological research has recently provided support for a negative effect of social class on prosocial behavior. However, research outside the field of psychology has mainly found evidence for positive or u-shaped relations. In the present research, we therefore thoroughly examined the effect of social class on prosocial behavior. Moreover, we analyzed whether this effect was moderated by the kind of observed prosocial behavior, the observed country, and the measure of social class. Across eight studies with large and representative international samples, we predominantly found positive effects of social class on prosociality: Higher class individuals were more likely to make a charitable donation and contribute a higher percentage of their family income to charity (32,090 ≥ N ≥ 3,957; Studies 1-3), were more likely to volunteer (37,136 ≥N ≥ 3,964; Studies 4-6), were more helpful (N = 3,902; Study 7), and were more trusting and trustworthy in an economic game when interacting with a stranger (N = 1,421; Study 8) than lower social class individuals. Although the effects of social class varied somewhat across the kinds of prosocial behavior, countries, and measures of social class, under no condition did we find the negative effect that would have been expected on the basis of previous results reported in the psychological literature. Possible explanations for this divergence and implications are discussed.

  4. Dark energy and modified gravity in the Effective Field Theory of Large-Scale Structure

    Science.gov (United States)

    Cusin, Giulia; Lewandowski, Matthew; Vernizzi, Filippo

    2018-04-01

    We develop an approach to compute observables beyond the linear regime of dark matter perturbations for general dark energy and modified gravity models. We do so by combining the Effective Field Theory of Dark Energy and Effective Field Theory of Large-Scale Structure approaches. In particular, we parametrize the linear and nonlinear effects of dark energy on dark matter clustering in terms of the Lagrangian terms introduced in a companion paper [1], focusing on Horndeski theories and assuming the quasi-static approximation. The Euler equation for dark matter is sourced, via the Newtonian potential, by new nonlinear vertices due to modified gravity and, as in the pure dark matter case, by the effects of short-scale physics in the form of the divergence of an effective stress tensor. The effective fluid introduces a counterterm in the solution to the matter continuity and Euler equations, which allows a controlled expansion of clustering statistics on mildly nonlinear scales. We use this setup to compute the one-loop dark-matter power spectrum.

  5. SUSY Higgs at the LHC large stop mixing effects and associated production

    CERN Document Server

    Bélanger, G; Sridhar, K

    2000-01-01

    We revisit the effect of the large stop mixing on the decay and production of the lightest SUSY Higgs at the LHC. We stress that whenever the inclusive 2-photon signature is substantially reduced, associated production, $Wh$ and $t\\bar t h$, with the subsequent decay of the Higgs into photons is enhanced and becomes an even more important discovery channel. We also point out that these reductions in the inclusive channel do not occur for the smallest Higgs mass where the significance is known to be lowest. We show that in such scenarios the Higgs can be produced in the decay of the heaviest stop. For not too heavy masses of the pseudo-scalar Higgs where the inclusive channel is even further reduced, we show that large stop mixing also allows the production of the pseudo-scalar Higgs through stop decays. These large mixing scenarios therefore offer much better prospects than previously thought. As a by-product we have recalculated stop1-stop1-h production at the LHC and give a first evaluation of stop1-stop1-Z...

  6. Modeling the Hydrologic Effects of Large-Scale Green Infrastructure Projects with GIS

    Science.gov (United States)

    Bado, R. A.; Fekete, B. M.; Khanbilvardi, R.

    2015-12-01

    Impervious surfaces in urban areas generate excess runoff, which in turn causes flooding, combined sewer overflows, and degradation of adjacent surface waters. Municipal environmental protection agencies have shown a growing interest in mitigating these effects with 'green' infrastructure practices that partially restore the perviousness and water holding capacity of urban centers. Assessment of the performance of current and future green infrastructure projects is hindered by the lack of adequate hydrological modeling tools; conventional techniques fail to account for the complex flow pathways of urban environments, and detailed analyses are difficult to prepare for the very large domains in which green infrastructure projects are implemented. Currently, no standard toolset exists that can rapidly and conveniently predict runoff, consequent inundations, and sewer overflows at a city-wide scale. We demonstrate how streamlined modeling techniques can be used with open-source GIS software to efficiently model runoff in large urban catchments. Hydraulic parameters and flow paths through city blocks, roadways, and sewer drains are automatically generated from GIS layers, and ultimately urban flow simulations can be executed for a variety of rainfall conditions. With this methodology, users can understand the implications of large-scale land use changes and green/gray storm water retention systems on hydraulic loading, peak flow rates, and runoff volumes.

  7. Large signal S-parameters: modeling and radiation effects in microwave power transistors

    International Nuclear Information System (INIS)

    Graham, E.D. Jr.; Chaffin, R.J.; Gwyn, C.W.

    1973-01-01

    Microwave power transistors are usually characterized by measuring the source and load impedances, efficiency, and power output at a specified frequency and bias condition in a tuned circuit. These measurements provide limited data for circuit design and yield essentially no information concerning broadbanding possibilities. Recently, a method using large signal S-parameters has been developed which provides a rapid and repeatable means for measuring microwave power transistor parameters. These large signal S-parameters have been successfully used to design rf power amplifiers. Attempts at modeling rf power transistors have in the past been restricted to a modified Ebers-Moll procedure with numerous adjustable model parameters. The modified Ebers-Moll model is further complicated by inclusion of package parasitics. In the present paper an exact one-dimensional device analysis code has been used to model the performance of the transistor chip. This code has been integrated into the SCEPTRE circuit analysis code such that chip, package and circuit performance can be coupled together in the analysis. Using []his computational tool, rf transistor performance has been examined with particular attention given to the theoretical validity of large-signal S-parameters and the effects of nuclear radiation on device parameters. (auth)

  8. On the renormalization of the effective field theory of large scale structures

    International Nuclear Information System (INIS)

    Pajer, Enrico; Zaldarriaga, Matias

    2013-01-01

    Standard perturbation theory (SPT) for large-scale matter inhomogeneities is unsatisfactory for at least three reasons: there is no clear expansion parameter since the density contrast is not small on all scales; it does not fully account for deviations at large scales from a perfect pressureless fluid induced by short-scale non-linearities; for generic initial conditions, loop corrections are UV-divergent, making predictions cutoff dependent and hence unphysical. The Effective Field Theory of Large Scale Structures successfully addresses all three issues. Here we focus on the third one and show explicitly that the terms induced by integrating out short scales, neglected in SPT, have exactly the right scale dependence to cancel all UV-divergences at one loop, and this should hold at all loops. A particularly clear example is an Einstein deSitter universe with no-scale initial conditions P in ∼ k n . After renormalizing the theory, we use self-similarity to derive a very simple result for the final power spectrum for any n, excluding two-loop corrections and higher. We show how the relative importance of different corrections depends on n. For n ∼ −1.5, relevant for our universe, pressure and dissipative corrections are more important than the two-loop corrections

  9. On the renormalization of the effective field theory of large scale structures

    Energy Technology Data Exchange (ETDEWEB)

    Pajer, Enrico [Department of Physics, Princeton University, Princeton, NJ 08544 (United States); Zaldarriaga, Matias, E-mail: enrico.pajer@gmail.com, E-mail: matiasz@ias.edu [Institute for Advanced Study, Princeton, NJ 08544 (United States)

    2013-08-01

    Standard perturbation theory (SPT) for large-scale matter inhomogeneities is unsatisfactory for at least three reasons: there is no clear expansion parameter since the density contrast is not small on all scales; it does not fully account for deviations at large scales from a perfect pressureless fluid induced by short-scale non-linearities; for generic initial conditions, loop corrections are UV-divergent, making predictions cutoff dependent and hence unphysical. The Effective Field Theory of Large Scale Structures successfully addresses all three issues. Here we focus on the third one and show explicitly that the terms induced by integrating out short scales, neglected in SPT, have exactly the right scale dependence to cancel all UV-divergences at one loop, and this should hold at all loops. A particularly clear example is an Einstein deSitter universe with no-scale initial conditions P{sub in} ∼ k{sup n}. After renormalizing the theory, we use self-similarity to derive a very simple result for the final power spectrum for any n, excluding two-loop corrections and higher. We show how the relative importance of different corrections depends on n. For n ∼ −1.5, relevant for our universe, pressure and dissipative corrections are more important than the two-loop corrections.

  10. Possible future effects of large-scale algae cultivation for biofuels on coastal eutrophication in Europe.

    Science.gov (United States)

    Blaas, Harry; Kroeze, Carolien

    2014-10-15

    Biodiesel is increasingly considered as an alternative for fossil diesel. Biodiesel can be produced from rapeseed, palm, sunflower, soybean and algae. In this study, the consequences of large-scale production of biodiesel from micro-algae for eutrophication in four large European seas are analysed. To this end, scenarios for the year 2050 are analysed, assuming that in the 27 countries of the European Union fossil diesel will be replaced by biodiesel from algae. Estimates are made for the required fertiliser inputs to algae parks, and how this may increase concentrations of nitrogen and phosphorus in coastal waters, potentially leading to eutrophication. The Global NEWS (Nutrient Export from WaterSheds) model has been used to estimate the transport of nitrogen and phosphorus to the European coastal waters. The results indicate that the amount of nitrogen and phosphorus in the coastal waters may increase considerably in the future as a result of large-scale production of algae for the production of biodiesel, even in scenarios assuming effective waste water treatment and recycling of waste water in algae production. To ensure sustainable production of biodiesel from micro-algae, it is important to develop cultivation systems with low nutrient losses to the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Large eddy simulation of a buoyancy-aided flow in a non-uniform channel – Buoyancy effects on large flow structures

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Y. [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom); School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); He, S., E-mail: s.he@sheffield.ac.uk [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2017-02-15

    Highlights: • Buoyancy may greatly redistribute the flow in a non-uniform channel. • Flow structures in the narrow gap are greatly changed when buoyancy is strong. • Large flow structures exist in wider gap, which is enhanced when heat is strong. • Buoyancy reduces mixing factor caused by large flow structures in narrow gap. - Abstract: It has been a long time since the ‘abnormal’ turbulent intensity distribution and high inter-sub-channel mixing rates were observed in the vicinity of the narrow gaps formed by the fuel rods in nuclear reactors. The extraordinary flow behaviour was first described as periodic flow structures by Hooper and Rehme (1984). Since then, the existences of large flow structures were demonstrated by many researchers in various non-uniform flow channels. It has been proved by many authors that the Strouhal number of the flow structure in the isothermal flow is dependent on the size of the narrow gap, not the Reynolds number once it is sufficiently large. This paper reports a numerical investigation on the effect of buoyancy on the large flow structures. A buoyancy-aided flow in a tightly-packed rod-bundle-like channel is modelled using large eddy simulation (LES) together with the Boussinesq approximation. The behaviour of the large flow structures in the gaps of the flow passage are studied using instantaneous flow fields, spectrum analysis and correlation analysis. It is found that the non-uniform buoyancy force in the cross section of the flow channel may greatly redistribute the velocity field once the overall buoyancy force is sufficiently strong, and consequently modify the large flow structures. The temporal and axial spatial scales of the large flow structures are influenced by buoyancy in a way similar to that turbulence is influenced. These scales reduce when the flow is laminarised, but start increasing in the turbulence regeneration region. The spanwise scale of the flow structures in the narrow gap remains more or

  12. Large anomalous Nernst and spin Nernst effects in the noncollinear antiferromagnets Mn3X (X =Sn ,Ge ,Ga )

    Science.gov (United States)

    Guo, Guang-Yu; Wang, Tzu-Cheng

    2017-12-01

    Noncollinear antiferromagnets have recently been attracting considerable interest partly due to recent surprising discoveries of the anomalous Hall effect (AHE) in them and partly because they have promising applications in antiferromagnetic spintronics. Here we study the anomalous Nernst effect (ANE), a phenomenon having the same origin as the AHE, and also the spin Nernst effect (SNE) as well as AHE and the spin Hall effect (SHE) in noncollinear antiferromagnetic Mn3X (X =Sn , Ge, Ga) within the Berry phase formalism based on ab initio relativistic band structure calculations. For comparison, we also calculate the anomalous Nernst conductivity (ANC) and anomalous Hall conductivity (AHC) of ferromagnetic iron as well as the spin Nernst conductivity (SNC) of platinum metal. Remarkably, the calculated ANC at room temperature (300 K) for all three alloys is huge, being 10-40 times larger than that of iron. Moreover, the calculated SNC for Mn3Sn and Mn3Ga is also larger, being about five times larger than that of platinum. This suggests that these antiferromagnets would be useful materials for thermoelectronic devices and spin caloritronic devices. The calculated ANC of Mn3Sn and iron are in reasonably good agreement with the very recent experiments. The calculated SNC of platinum also agrees with the very recent experiments in both sign and magnitude. The calculated thermoelectric and thermomagnetic properties are analyzed in terms of the band structures as well as the energy-dependent AHC, ANC, SNC, and spin Hall conductivity via the Mott relations.

  13. Effects of a large wildfire on vegetation structure in a variable fire mosaic.

    Science.gov (United States)

    Foster, C N; Barton, P S; Robinson, N M; MacGregor, C I; Lindenmayer, D B

    2017-12-01

    Management guidelines for many fire-prone ecosystems highlight the importance of maintaining a variable mosaic of fire histories for biodiversity conservation. Managers are encouraged to aim for fire mosaics that are temporally and spatially dynamic, include all successional states of vegetation, and also include variation in the underlying "invisible mosaic" of past fire frequencies, severities, and fire return intervals. However, establishing and maintaining variable mosaics in contemporary landscapes is subject to many challenges, one of which is deciding how the fire mosaic should be managed following the occurrence of large, unplanned wildfires. A key consideration for this decision is the extent to which the effects of previous fire history on vegetation and habitats persist after major wildfires, but this topic has rarely been investigated empirically. In this study, we tested to what extent a large wildfire interacted with previous fire history to affect the structure of forest, woodland, and heath vegetation in Booderee National Park in southeastern Australia. In 2003, a summer wildfire burned 49.5% of the park, increasing the extent of recently burned vegetation (post-fire) to more than 72% of the park area. We tracked the recovery of vegetation structure for nine years following the wildfire and found that the strength and persistence of fire effects differed substantially between vegetation types. Vegetation structure was modified by wildfire in forest, woodland, and heath vegetation, but among-site variability in vegetation structure was reduced only by severe fire in woodland vegetation. There also were persistent legacy effects of the previous fire regime on some attributes of vegetation structure including forest ground and understorey cover, and woodland midstorey and overstorey cover. For example, woodland midstorey cover was greater on sites with higher fire frequency, irrespective of the severity of the 2003 wildfire. Our results show that even

  14. Surprising results from a search for effective disinfectants for Tobacco mosaic virus-contaminated tools

    Science.gov (United States)

    Tobacco mosaic virus (TMV) and four other tobamoviruses infected multiple petunia cultivars without producing obvious viral symptoms. A single cutting event on a TMV-infected plant was sufficient for transmission to many plants subsequently cut with the same clippers. A number of 'old standbys' an...

  15. The effects of surprise political events on quoted firms: The March 2004 election in Spain

    OpenAIRE

    Castells, Pau; Trillas, Francesc

    2013-01-01

    In the last days of the electoral campaign for the 2004 general election in Spain, on Thursday March 11th 2004, a series of simultaneous terror attacks caused the death of 191 persons in commuting trains in the capital Madrid. Four days later, the opposition party won the election, against all predictions that were made prior to the terror attacks. This change in expectations presents a unique opportunity to take advantage of event study techniques to test some politico-economic hypotheses. T...

  16. Quantitation of the late effects of x radiation on the large intestine

    International Nuclear Information System (INIS)

    Black, W.C.; Gomez, L.S.; Yuhas, J.M.; Kligerman, M.M.

    1980-01-01

    A model for quantitating late effects of x radiation on the large intestine utilizing the rectum of the Sprague-Dawley rat is reported. This model was constructed prefatory to establishing relative biological effectiveness for negative pions as a component of preclinical trials at the Clinton P. Anderson Meson Physics Facility. The endpoint involves microscopic evaluation of the severity of the experimental lesion, compared with surgically resected bowel lesions we have studied following clinical radiation exposure of the bowel. Individual components of the overall lesion include mucosal ulceration, a typical epithelial regeneration, colitis cystica profunda, fibrosis, and vascular sclerosis. Dose response curves were established for animals receiving 1, 2, 5 and 10 fractions with groups sacrificed at both four and 12 months after completion of radiation exposures

  17. Effects of Collar Permeability on the Field Quality of the Large Aperture Quadrupoles for the LHC

    CERN Document Server

    Catalan-Lasheras, N; Kirby, G; Mess, K H; Ostojic, R; Russenschuck, Stephan

    2008-01-01

    The LHC contains a number of large aperture quadrupoles (MQY) in the insertions. The acceptance of these magnets was based on warm magnetic measurements performed before delivery to CERN. During the series production of the MQY quadrupoles, the permeability of the collars drifted from the nominal value, and effects on the transfer function and multipole components became evident. To study the effects on the magnetic field, variable permeability of the stainless-steel collars as a function of local field and temperature was introduced into a numerical model. Comparing the results with measured data, we could isolate the contribution of permeability deviation on the magnetic field quality. The extrapolation of transfer function and field multipoles to operating temperature and current gives the necessary offsets, which are compared with measurements on a reduced set of magnets.

  18. Effect of relative pile’s stiffness on lateral pile response under loading of large eccentricity

    DEFF Research Database (Denmark)

    Zania, Varvara; Hededal, Ole; Klinkvort, R.T.

    2015-01-01

    The wide application of monopiles as foundations for offshore wind turbines has raised the issue of the suitability of the p –y curves proposed by API for lateral pile loading, since the latter were developed after full-scale tests on flexible and slender piles. This study investigates the role...... of the relative pile’s stiffness, when it is subjected to lateral load of large eccentricity. Employing centrifuge experiments, a hollow steel pile well instrumented with strain gauge pairs has been subjected to lateral load. The bending moment distribution of the model pile embedded in uniform, dense, dry sand...... was obtained under two different stress levels and two different embedment depths. Hence, the p – y curves were obtained providing an insight into the effect of the relative pile’s stiffness on the soil – pile interaction, while the effect of the installation process could also be evaluated....

  19. Observation of large magnetocaloric effect in equiatomic binary compound ErZn

    Directory of Open Access Journals (Sweden)

    Lingwei Li

    2017-05-01

    Full Text Available The magnetism, magnetocaloric effect and universal behaviour in rare earth Zinc binary compound of ErZn have been studied. The ErZn compound undergoes a second order paramagnetic (PM to ferromagnetic (FM transition at Curie temperature of TC ∼ 20 K. The ErZn compound exhibits a large reversible magnetocaloric effect (MCE around its own TC. The rescaled magnetic entropy change curves overlap with each other under various magnetic field changes, further confirming the ErZn with the second order phase transition. For the magnetic field change of 0-7 T, the maximum values of the magnetic entropy change (−ΔSMmax, relative cooling power (RCP and refrigerant capacity (RC for ErZn are 23.3 J/kg K, 581 J/kg and 437 J/kg, respectively.

  20. Effects of large-angle Coulomb collisions on inertial confinement fusion plasmas.

    Science.gov (United States)

    Turrell, A E; Sherlock, M; Rose, S J

    2014-06-20

    Large-angle Coulomb collisions affect the rates of energy and momentum exchange in a plasma, and it is expected that their effects will be important in many plasmas of current research interest, including in inertial confinement fusion. Their inclusion is a long-standing problem, and the first fully self-consistent method for calculating their effects is presented. This method is applied to "burn" in the hot fuel in inertial confinement fusion capsules and finds that the yield increases due to an increase in the rate of temperature equilibration between electrons and ions which is not predicted by small-angle collision theories. The equilibration rate increases are 50%-100% for number densities of 10(30)  m(-3) and temperatures around 1 keV.

  1. Variability in mutational fitness effects prevents full lethal transitions in large quasispecies populations

    Science.gov (United States)

    Sardanyés, Josep; Simó, Carles; Martínez, Regina; Solé, Ricard V.; Elena, Santiago F.

    2014-04-01

    The distribution of mutational fitness effects (DMFE) is crucial to the evolutionary fate of quasispecies. In this article we analyze the effect of the DMFE on the dynamics of a large quasispecies by means of a phenotypic version of the classic Eigen's model that incorporates beneficial, neutral, deleterious, and lethal mutations. By parameterizing the model with available experimental data on the DMFE of Vesicular stomatitis virus (VSV) and Tobacco etch virus (TEV), we found that increasing mutation does not totally push the entire viral quasispecies towards deleterious or lethal regions of the phenotypic sequence space. The probability of finding regions in the parameter space of the general model that results in a quasispecies only composed by lethal phenotypes is extremely small at equilibrium and in transient times. The implications of our findings can be extended to other scenarios, such as lethal mutagenesis or genomically unstable cancer, where increased mutagenesis has been suggested as a potential therapy.

  2. Large persistent photochromic effect due to DX centers in AlSb doped with selenium

    International Nuclear Information System (INIS)

    Becla, P.; Witt, A.G.

    1995-04-01

    A large photochromic effect has been observed in bulk AlSb crystals doped with Se. Illumination with light of energy higher than 1 eV leads to an increase of the absorption coefficient in the spectral range 0.1 to 1.6 eV. The enhanced absorption is persistent at temperatures below about K. The effect is a manifestation of a DX-like bistability of Se donors. The illumination transfers the from the DX center to a metastable hydrogenic level. The increased absorption with peaks around 0.2 eV and 0.5 is due to photoionization from the donor level to X l and X 3 minima of the conduction band

  3. Simulated effects of host fish distribution on juvenile unionid mussel dispersal in a large river

    Science.gov (United States)

    Daraio, J.A.; Weber, L.J.; Zigler, S.J.; Newton, T.J.; Nestler, J.M.

    2012-01-01

    Larval mussels (Family Unionidae) are obligate parasites on fish, and after excystment from their host, as juveniles, they are transported with flow. We know relatively little about the mechanisms that affect dispersal and subsequent settlement of juvenile mussels in large rivers. We used a three-dimensional hydrodynamic model of a reach of the Upper Mississippi River with stochastic Lagrangian particle tracking to simulate juvenile dispersal. Sensitivity analyses were used to determine the importance of excystment location in two-dimensional space (lateral and longitudinal) and to assess the effects of vertical location (depth in the water column) on dispersal distances and juvenile settling distributions. In our simulations, greater than 50% of juveniles mussels settled on the river bottom within 500 m of their point of excystment, regardless of the vertical location of the fish in the water column. Dispersal distances were most variable in environments with higher velocity and high gradients in velocity, such as along channel margins, near the channel bed, or where effects of river bed morphology caused large changes in hydraulics. Dispersal distance was greater and variance was greater when juvenile excystment occurred in areas where vertical velocity (w) was positive (indicating an upward velocity) than when w was negative. Juvenile dispersal distance is likely to be more variable for mussels species whose hosts inhabit areas with steeper velocity gradients (e.g. channel margins) than a host that generally inhabits low-flow environments (e.g. impounded areas).

  4. Effects of baryons on the statistical properties of large scale structure of the Universe

    International Nuclear Information System (INIS)

    Guillet, T.

    2010-01-01

    Observations of weak gravitational lensing will provide strong constraints on the cosmic expansion history and the growth rate of large scale structure, yielding clues to the properties and nature of dark energy. Their interpretation is impacted by baryonic physics, which are expected to modify the total matter distribution at small scales. My work has focused on determining and modeling the impact of baryons on the statistics of the large scale matter distribution in the Universe. Using numerical simulations, I have extracted the effect of baryons on the power spectrum, variance and skewness of the total density field as predicted by these simulations. I have shown that a model based on the halo model construction, featuring a concentrated central component to account for cool condensed baryons, is able to reproduce accurately, and down to very small scales, the measured amplifications of both the variance and skewness of the density field. Because of well-known issues with baryons in current cosmological simulations, I have extended the central component model to rely on as many observation-based ingredients as possible. As an application, I have studied the effect of baryons on the predictions of the upcoming Euclid weak lensing survey. During the course of this work, I have also worked at developing and extending the RAMSES code, in particular by developing a parallel self-gravity solver, which offers significant performance gains, in particular for the simulation of some astrophysical setups such as isolated galaxy or cluster simulations. (author) [fr

  5. Safety Effect Analysis of the Large-Scale Design Changes in a Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun-Chan; Lee, Hyun-Gyo [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2015-05-15

    These activities were predominantly focused on replacing obsolete systems with new systems, and these efforts were not only to prolong the plant life, but also to guarantee the safe operation of the units. This review demonstrates the safety effect evaluation using the probabilistic safety assessment (PSA) of the design changes, system improvements, and Fukushima accident action items for Kori unit 1 (K1). For the large scale of system design changes for K1, the safety effects from the PSA perspective were reviewed using the risk quantification results before and after the system improvements. This evaluation considered the seven significant design changes including the replacement of the control building air conditioning system and the performance improvement of the containment sump using a new filtering system as well as above five system design changes. The analysis results demonstrated that the CDF was reduced by 12% overall from 1.62E-5/y to 1.43E-5/y. The CDF reduction was larger in the transient group than in the loss of coolant accident (LOCA) group. In conclusion, the analysis using the K1 PSA model supports that the plant safety has been appropriately maintained after the large-scale design changes in consideration of the changed operation factors and failure modes due to the system improvements.

  6. Time delay effects on large-scale MR damper based semi-active control strategies

    International Nuclear Information System (INIS)

    Cha, Y-J; Agrawal, A K; Dyke, S J

    2013-01-01

    This paper presents a detailed investigation on the robustness of large-scale 200 kN MR damper based semi-active control strategies in the presence of time delays in the control system. Although the effects of time delay on stability and performance degradation of an actively controlled system have been investigated extensively by many researchers, degradation in the performance of semi-active systems due to time delay has yet to be investigated. Since semi-active systems are inherently stable, instability problems due to time delay are unlikely to arise. This paper investigates the effects of time delay on the performance of a building with a large-scale MR damper, using numerical simulations of near- and far-field earthquakes. The MR damper is considered to be controlled by four different semi-active control algorithms, namely (i) clipped-optimal control (COC), (ii) decentralized output feedback polynomial control (DOFPC), (iii) Lyapunov control, and (iv) simple-passive control (SPC). It is observed that all controllers except for the COC are significantly robust with respect to time delay. On the other hand, the clipped-optimal controller should be integrated with a compensator to improve the performance in the presence of time delay. (paper)

  7. Effects of fluid flow on heat transfer in large rotating electrical machines

    International Nuclear Information System (INIS)

    Lancial, Nicolas

    2014-01-01

    EDF operates a large number of electrical rotating machines in its electricity generation capacity. Thermal stresses which affect them can cause local heating, sufficient to damage their integrity. The present work contributes to provide methodologies for detecting hot spots in these machines, better understanding the topology of rotating flows and identifying their effects on heat transfer. Several experimental scale model were used by increasing their complexity to understand and validate the numerical simulations. A first study on a turbulent wall jet over a non-confined backward-facing step (half-pole hydro-generator) notes significant differences compared to results from confined case: both of them are present in an hydro-generator. A second study was done on a small confined rotating scale model to determinate the effects of a Taylor-Couette-Poiseuille on temperature distribution and position of hot spots on the heated rotor, by studying the overall flow regimes flow. These studies have helped to obtain a reliable method based on conjugate heat transfer (CHT) simulations. Another method, based on FEM coupled with the use of an inverse method, has been studied on a large model of hydraulic generator so as to solve the computation time issue of the first methodology. It numerically calculates the convective heat transfer from temperature measurements, but depends on the availability of experimental data. This work has also developed new no-contact measurement techniques as the use of a high-frequency pyrometer which can be applied on rotating machines for monitoring temperature. (author)

  8. HIFU procedures at moderate intensities-effect of large blood vessels

    International Nuclear Information System (INIS)

    Hariharan, P; Myers, M R; Banerjee, R K

    2007-01-01

    A three-dimensional computational model is presented for studying the efficacy of high-intensity focused ultrasound (HIFU) procedures targeted near large blood vessels. The analysis applies to procedures performed at intensities below the threshold for cavitation, boiling and highly nonlinear propagation, but high enough to increase tissue temperature a few degrees per second. The model is based upon the linearized KZK equation and the bioheat equation in tissue. In the blood vessel the momentum and energy equations are satisfied. The model is first validated in a tissue phantom, to verify the absence of bubble formation and nonlinear effects. Temperature rise and lesion-volume calculations are then shown for different beam locations and orientations relative to a large vessel. Both single and multiple ablations are considered. Results show that when the vessel is located within about a beam width (few mm) of the ultrasound beam, significant reduction in lesion volume is observed due to blood flow. However, for gaps larger than a beam width, blood flow has no major effect on the lesion formation. Under the clinically representative conditions considered, the lesion volume is reduced about 40% (relative to the no-flow case) when the beam is parallel to the blood vessel, compared to about 20% for a perpendicular orientation. Procedures involving multiple ablation sites are affected less by blood flow than single ablations. The model also suggests that optimally focused transducers can generate lesions that are significantly larger (>2 times) than the ones produced by highly focused beams

  9. HIFU procedures at moderate intensities-effect of large blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Hariharan, P [Mechanical, Industrial, and Nuclear Engineering Department, University of Cincinnati, Cincinnati, OH (United States); Myers, M R [Division of Solid and Fluid Mechanics, Center for Devices and Radiological Health, US Food and Drug Administration, 10903 New Hampshire Avenue, Building 62, Silver Spring, MD 20993-0002 (United States); Banerjee, R K [Mechanical, Industrial, and Nuclear Engineering Department, University of Cincinnati, Cincinnati, OH (United States)

    2007-07-21

    A three-dimensional computational model is presented for studying the efficacy of high-intensity focused ultrasound (HIFU) procedures targeted near large blood vessels. The analysis applies to procedures performed at intensities below the threshold for cavitation, boiling and highly nonlinear propagation, but high enough to increase tissue temperature a few degrees per second. The model is based upon the linearized KZK equation and the bioheat equation in tissue. In the blood vessel the momentum and energy equations are satisfied. The model is first validated in a tissue phantom, to verify the absence of bubble formation and nonlinear effects. Temperature rise and lesion-volume calculations are then shown for different beam locations and orientations relative to a large vessel. Both single and multiple ablations are considered. Results show that when the vessel is located within about a beam width (few mm) of the ultrasound beam, significant reduction in lesion volume is observed due to blood flow. However, for gaps larger than a beam width, blood flow has no major effect on the lesion formation. Under the clinically representative conditions considered, the lesion volume is reduced about 40% (relative to the no-flow case) when the beam is parallel to the blood vessel, compared to about 20% for a perpendicular orientation. Procedures involving multiple ablation sites are affected less by blood flow than single ablations. The model also suggests that optimally focused transducers can generate lesions that are significantly larger (>2 times) than the ones produced by highly focused beams.

  10. Effect of Large Negative Phase of Blast Loading on Structural Response of RC Elements

    Directory of Open Access Journals (Sweden)

    Syed Zubair Iman

    2016-01-01

    Full Text Available Structural response of reinforced concrete (RC elements for analysis and design are often obtained using the positive phase of the blast pressure curve disregarding the negative phase assuming insignificant contribution from the negative phase of the loading. Although, some insight on the effect of negative phase of blast pressure based on elastic single-degree-of-freedom (SDOF analysis was presented before, the influence of negative phase on different types of resistance functions of SDOF models and on realistic finite element analysis has not been explored. In this study, the effects of inclusion of pulse negative phase on structural response of RC elements from SDOF analysis and from more detailed finite element analysis have been investigated. Investigation of SDOF part has been conducted using MATLAB code that utilizes non-linear resistance functions of SDOF model. Detailed numerical investigation using finite element code DIANA was conducted on the significance of the negative phase on structural response. In the FE model, different support stiffness was used to explore the effect of support stiffness on the structural response due to blast negative phase. Results from SDOF and FE analyses present specific situations where the effect of large negative phase was found to be significant on the structural response of RC elements.

  11. A Methodology of Health Effects Estimation from Air Pollution in Large Asian Cities

    Directory of Open Access Journals (Sweden)

    Keiko Hirota

    2017-09-01

    Full Text Available The increase of health effects caused by air pollution seems to be a growing concern in Asian cities with increasing motorization. This paper discusses methods of estimating the health effects of air pollution in large Asian cities. Due to the absence of statistical data in Asia, this paper carefully chooses the methodology using data of the Japanese compensation system. A basic idea of health effects will be captured from simple indicators, such as population and air quality, in a correlation model. This correlation model enables more estimation results of respiratory mortality caused by air pollution to be yielded than by using the relative model. The correlation model could be an alternative method to estimate mortality besides the relative risk model since the results of the correlation model are comparable with those of the relative model by city and by time series. The classification of respiratory diseases is not known from the statistical yearbooks in many countries. Estimation results could support policy decision-making with respect to public health in a cost-effective way.

  12. Control rod shadowing and anti-shadowing effects in a large gas-cooled fast reactor

    International Nuclear Information System (INIS)

    Girardin, G.; Chawla, R.; Rimpault, G.; Coddington, P.

    2007-01-01

    An investigation of control rod shadowing and anti-shadowing (interaction) effects has been carried out in the context of a design study of the control rod pattern for the large 2400 MWth Generation IV Gas-cooled Fast Reactor (GFR). For the calculations, the deterministic code system ERANOS-2.0 has been used, in association with a full core model including a European Fast Reactor (EFR)-type pattern for the control rods. More specifically, the core contains a total of 33 control (CSD) and safety (DSD) rods implemented in three banks: -1) a first bank of 6 CSD rods, placed at 64 cm from core centre in the inner fuel zone (Pu content 16.3 % vol.), -2) a safety bank consisting of 9 DSD rods, at an average distance of 118 cm, and -3) a third bank with 18 CSD rods, placed at 171 cm, i.e. at the interface between the inner and outer (Pu content 19.2 % vol.) core regions. Each control rod has been modelled as a homogeneous material containing 90%-enriched B 4 C, steel and helium. Considerable shadowing effects have been observed between the first bank and the safety bank, as also between individual rods within the first bank. Large anti-shadowing effects take place in an even greater number of the studied rod configurations. The largest interaction is between the two CSD banks, the anti-shadowing value being 46% in this case, implying that the total rod worth is increased by a factor of almost 2 when compared to the sum of the individual bank values. Additional investigations have been performed, in particular the computation of the first order eigenvalue and the eigenvalue separation. The main finding is that the interactions are lower when one of the control rod banks is located at a radial position corresponding to half the core radius. (authors)

  13. Large Spatial and Temporal Separations of Cause and Effect in Policy Making - Dealing with Non-linear Effects

    Science.gov (United States)

    McCaskill, John

    There can be large spatial and temporal separation of cause and effect in policy making. Determining the correct linkage between policy inputs and outcomes can be highly impractical in the complex environments faced by policy makers. In attempting to see and plan for the probable outcomes, standard linear models often overlook, ignore, or are unable to predict catastrophic events that only seem improbable due to the issue of multiple feedback loops. There are several issues with the makeup and behaviors of complex systems that explain the difficulty many mathematical models (factor analysis/structural equation modeling) have in dealing with non-linear effects in complex systems. This chapter highlights those problem issues and offers insights to the usefulness of ABM in dealing with non-linear effects in complex policy making environments.

  14. Thermal motion in proteins: Large effects on the time-averaged interaction energies

    International Nuclear Information System (INIS)

    Goethe, Martin; Rubi, J. Miguel; Fita, Ignacio

    2016-01-01

    As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothing effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.

  15. Thermal motion in proteins: Large effects on the time-averaged interaction energies

    Energy Technology Data Exchange (ETDEWEB)

    Goethe, Martin, E-mail: martingoethe@ub.edu; Rubi, J. Miguel [Departament de Física Fonamental, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Fita, Ignacio [Institut de Biologia Molecular de Barcelona, Baldiri Reixac 10, 08028 Barcelona (Spain)

    2016-03-15

    As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothing effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.

  16. Modeling the acute health effects of astronauts from exposure to large solar particle events.

    Science.gov (United States)

    Hu, Shaowen; Kim, Myung-Hee Y; McClellan, Gene E; Cucinotta, Francis A

    2009-04-01

    Radiation exposure from Solar Particle Events (SPE) presents a significant health concern for astronauts for exploration missions outside the protection of the Earth's magnetic field, which could impair their performance and result in the possibility of failure of the mission. Assessing the potential for early radiation effects under such adverse conditions is of prime importance. Here we apply a biologically based mathematical model that describes the dose- and time-dependent early human responses that constitute the prodromal syndromes to consider acute risks from SPEs. We examine the possible early effects on crews from exposure to some historically large solar events on lunar and/or Mars missions. The doses and dose rates of specific organs were calculated using the Baryon radiation transport (BRYNTRN) code and a computerized anatomical man model, while the hazard of the early radiation effects and performance reduction were calculated using the Radiation-Induced Performance Decrement (RIPD) code. Based on model assumptions we show that exposure to these historical events would cause moderate early health effects to crew members inside a typical spacecraft or during extra-vehicular activities, if effective shielding and medical countermeasure tactics were not provided. We also calculate possible even worse cases (double intensity, multiple occurrences in a short period of time, etc.) to estimate the severity, onset and duration of various types of early illness. Uncertainties in the calculation due to limited data on relative biological effectiveness and dose-rate modifying factors for protons and secondary radiation, and the identification of sensitive sites in critical organs are discussed.

  17. Surprisal analysis of Glioblastoma Multiform (GBM) microRNA dynamics unveils tumor specific phenotype.

    Science.gov (United States)

    Zadran, Sohila; Remacle, Francoise; Levine, Raphael

    2014-01-01

    Gliomablastoma multiform (GBM) is the most fatal form of all brain cancers in humans. Currently there are limited diagnostic tools for GBM detection. Here, we applied surprisal analysis, a theory grounded in thermodynamics, to unveil how biomolecule energetics, specifically a redistribution of free energy amongst microRNAs (miRNAs), results in a system deviating from a non-cancer state to the GBM cancer -specific phenotypic state. Utilizing global miRNA microarray expression data of normal and GBM patients tumors, surprisal analysis characterizes a miRNA system response capable of distinguishing GBM samples from normal tissue biopsy samples. We indicate that the miRNAs contributing to this system behavior is a disease phenotypic state specific to GBM and is therefore a unique GBM-specific thermodynamic signature. MiRNAs implicated in the regulation of stochastic signaling processes crucial in the hallmarks of human cancer, dominate this GBM-cancer phenotypic state. With this theory, we were able to distinguish with high fidelity GBM patients solely by monitoring the dynamics of miRNAs present in patients' biopsy samples. We anticipate that the GBM-specific thermodynamic signature will provide a critical translational tool in better characterizing cancer types and in the development of future therapeutics for GBM.

  18. Cloud Surprises in Moving NASA EOSDIS Applications into Amazon Web Services

    Science.gov (United States)

    Mclaughlin, Brett

    2017-01-01

    NASA ESDIS has been moving a variety of data ingest, distribution, and science data processing applications into a cloud environment over the last 2 years. As expected, there have been a number of challenges in migrating primarily on-premises applications into a cloud-based environment, related to architecture and taking advantage of cloud-based services. What was not expected is a number of issues that were beyond purely technical application re-architectures. We ran into surprising network policy limitations, billing challenges in a government-based cost model, and difficulty in obtaining certificates in an NASA security-compliant manner. On the other hand, this approach has allowed us to move a number of applications from local hosting to the cloud in a matter of hours (yes, hours!!), and our CMR application now services 95% of granule searches and an astonishing 99% of all collection searches in under a second. And most surprising of all, well, you'll just have to wait and see the realization that caught our entire team off guard!

  19. Combining eastern and western practices for safe and effective endoscopic resection of large complex colorectal lesions.

    Science.gov (United States)

    Emmanuel, Andrew; Gulati, Shraddha; Burt, Margaret; Hayee, Bu'Hussain; Haji, Amyn

    2018-05-01

    Endoscopic resection of large colorectal polyps is well established. However, significant differences in technique exist between eastern and western interventional endoscopists. We report the results of endoscopic resection of large complex colorectal lesions from a specialist unit that combines eastern and western techniques for assessment and resection. Endoscopic resections of colorectal lesions of at least 2 cm were included. Lesions were assessed using magnification chromoendoscopy supplemented by colonoscopic ultrasound in selected cases. A lesion-specific approach to resection with endoscopic mucosal resection or endoscopic submucosal dissection (ESD) was used. Surveillance endoscopy was performed at 3 (SC1) and 12 (SC2) months. Four hundred and sixty-six large (≥20 mm) colorectal lesions (mean size 54.8 mm) were resected. Three hundread and fifty-six were resected using endoscopic mucosal resection and 110 by ESD or hybrid ESD. Fifty-one percent of lesions had been subjected to previous failed attempts at resection or heavy manipulation (≥6 biopsies). Nevertheless, endoscopic resection was deemed successful after an initial attempt in 98%. Recurrence occurred in 15% and could be treated with endoscopic resection in most. Only two patients required surgery for perforation. Nine patients had postprocedure bleeding; only two required endoscopic clips. Ninety-six percent of patients without invasive cancer were free from recurrence and had avoided surgery at last follow-up. Combining eastern and western practices for assessment and resection results in safe and effective organ-conserving treatment of complex colorectal lesions. Accurate assessment before and after resection using magnification chromoendoscopy and a lesion-specific approach to resection, incorporating ESD where appropriate, are important factors in achieving these results.

  20. Statistical Analysis of Large Simulated Yield Datasets for Studying Climate Effects

    Science.gov (United States)

    Makowski, David; Asseng, Senthold; Ewert, Frank; Bassu, Simona; Durand, Jean-Louis; Martre, Pierre; Adam, Myriam; Aggarwal, Pramod K.; Angulo, Carlos; Baron, Chritian; hide

    2015-01-01

    Many studies have been carried out during the last decade to study the effect of climate change on crop yields and other key crop characteristics. In these studies, one or several crop models were used to simulate crop growth and development for different climate scenarios that correspond to different projections of atmospheric CO2 concentration, temperature, and rainfall changes (Semenov et al., 1996; Tubiello and Ewert, 2002; White et al., 2011). The Agricultural Model Intercomparison and Improvement Project (AgMIP; Rosenzweig et al., 2013) builds on these studies with the goal of using an ensemble of multiple crop models in order to assess effects of climate change scenarios for several crops in contrasting environments. These studies generate large datasets, including thousands of simulated crop yield data. They include series of yield values obtained by combining several crop models with different climate scenarios that are defined by several climatic variables (temperature, CO2, rainfall, etc.). Such datasets potentially provide useful information on the possible effects of different climate change scenarios on crop yields. However, it is sometimes difficult to analyze these datasets and to summarize them in a useful way due to their structural complexity; simulated yield data can differ among contrasting climate scenarios, sites, and crop models. Another issue is that it is not straightforward to extrapolate the results obtained for the scenarios to alternative climate change scenarios not initially included in the simulation protocols. Additional dynamic crop model simulations for new climate change scenarios are an option but this approach is costly, especially when a large number of crop models are used to generate the simulated data, as in AgMIP. Statistical models have been used to analyze responses of measured yield data to climate variables in past studies (Lobell et al., 2011), but the use of a statistical model to analyze yields simulated by complex

  1. Large lateral photovoltaic effect with ultrafast relaxation time in SnSe/Si junction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xianjie; Zhao, Xiaofeng; Hu, Chang; Zhang, Yang; Song, Bingqian; Zhang, Lingli; Liu, Weilong; Lv, Zhe; Zhang, Yu; Sui, Yu, E-mail: suiyu@hit.edu.cn [Department of Physics, Harbin Institute of Technology, Harbin 150001 (China); Tang, Jinke [Department of Physics and Astronomy, University of Wyoming, Laramie, Wyoming 82071 (United States); Song, Bo, E-mail: songbo@hit.edu.cn [Department of Physics, Harbin Institute of Technology, Harbin 150001 (China); Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150001 (China)

    2016-07-11

    In this paper, we report a large lateral photovoltaic effect (LPE) with ultrafast relaxation time in SnSe/p-Si junctions. The LPE shows a linear dependence on the position of the laser spot, and the position sensitivity is as high as 250 mV mm{sup −1}. The optical response time and the relaxation time of the LPE are about 100 ns and 2 μs, respectively. The current-voltage curve on the surface of the SnSe film indicates the formation of an inversion layer at the SnSe/p-Si interface. Our results clearly suggest that most of the excited-electrons diffuse laterally in the inversion layer at the SnSe/p-Si interface, which results in a large LPE with ultrafast relaxation time. The high positional sensitivity and ultrafast relaxation time of the LPE make the SnSe/p-Si junction a promising candidate for a wide range of optoelectronic applications.

  2. Large scale vibration tests on pile-group effects using blast-induced ground motion

    International Nuclear Information System (INIS)

    Katsuichirou Hijikata; Hideo Tanaka; Takayuki Hashimoto; Kazushige Fujiwara; Yuji Miyamoto; Osamu Kontani

    2005-01-01

    Extensive vibration tests have been performed on pile-supported structures at a large-scale mining site. Ground motions induced by large-scale blasting operations were used as excitation forces for vibration tests. The main objective of this research is to investigate the dynamic behavior of pile-supported structures, in particular, pile-group effects. Two test structures were constructed in an excavated 4 m deep pit. Their test-structures were exactly the same. One structure had 25 steel piles and the other had 4 piles. The test pit was backfilled with sand of appropriate grain size distributions to obtain good compaction, especially between the 25 piles. Accelerations were measured at the structures, in the test pit and in the adjacent free field, and pile strains were measured. Dynamic modal tests of the pile-supported structures and PS measurements of the test pit were performed before and after the vibration tests to detect changes in the natural frequencies of the soil-pile-structure systems and the soil stiffness. The vibration tests were performed six times with different levels of input motions. The maximum horizontal acceleration recorded at the adjacent ground surface varied from 57 cm/s 2 to 1,683 cm/s 2 according to the distances between the test site and the blast areas. (authors)

  3. Morphological changes connected with irradiation of large fields in dogs and with the effect of automyelotransplantation

    International Nuclear Information System (INIS)

    Klestova, O.V.; Sil'chenko, N.N.; Stanzhevskaya, T.I.; Strelin, G.S.; Vishnyakov, Yu.S.; Gubareva, A.V.; Skripkina, N.S.

    1983-01-01

    Dogs have been used to study the effect of automyelotransplantation on processes of post-radiation recovery of hemopoietic organs in large-field fractionated irradiation and morphological changes in some internal organs irradiated with different doses. Dogs of both sexes were irradiated in the gamma device twice a week alternately from the back and from the stomach with fractions of 8 Gy for the radiation field. The integral dose for all irradiated sections is 48 Gy. Automyelotransplantation of bone marrow is done after irradiation of the upper part of the body of the animal. Morphological changes in bone marrow, spleen, gastrointestinal tract, liver, heart and lungs, are found. It is shown that automyelotransplantation from non-irradiated section in the case of large-field radiation promotes the recovery of bone marrow and other homopoietic organs which is expressed in the intensification of repopulation of bone marrow of breast bone and lymphoid hemopoiesis in spleen. It is noted that such reparation of bone marrow can play a positive role in the recovery of bone marrow syndrome of radiation disease

  4. High prices for rare species can drive large populations extinct: the anthropogenic Allee effect revisited.

    Science.gov (United States)

    Holden, Matthew H; McDonald-Madden, Eve

    2017-09-21

    Consumer demand for plant and animal products threatens many populations with extinction. The anthropogenic Allee effect (AAE) proposes that such extinctions can be caused by prices for wildlife products increasing with species rarity. This price-rarity relationship creates financial incentives to extract the last remaining individuals of a population, despite higher search and harvest costs. The AAE has become a standard approach for conceptualizing the threat of economic markets on endangered species. Despite its potential importance for conservation, AAE theory is based on a simple graphical model with limited analysis of possible population trajectories. By specifying a general class of functions for price-rarity relationships, we show that the classic theory can understate the risk of species extinction. AAE theory proposes that only populations below a critical Allee threshold will go extinct due to increasing price-rarity relationships. Our analysis shows that this threshold can be much higher than the original theory suggests, depending on initial harvest effort. More alarmingly, even species with population sizes above this Allee threshold, for which AAE predicts persistence, can be destined to extinction. Introducing even a minimum price for harvested individuals, close to zero, can cause large populations to cross the classic anthropogenic Allee threshold on a trajectory towards extinction. These results suggest that traditional AAE theory may give a false sense of security when managing large harvested populations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Revealing the large extra dimension effective interaction at an e+e- collider with polarized beams

    International Nuclear Information System (INIS)

    Pankov, A. A.; Tsytrinov, A. V.; Paver, N.

    2007-01-01

    Several types of new physics scenarios are represented by contactlike effective interactions. An example is the exchange of nonstandard quanta of very large mass scales, beyond the kinematical limit for direct production set by the available collider energy. This kind of interactions can be revealed only through deviations of observables from the standard model predictions. If such deviations were observed, the relevant source should be identified among the possible models that could explain them. Here, we assess the expected 'identification reach' on the ADD model of gravity in large compactified extra dimensions, against the compositeness-inspired four-fermion contact interaction. As basic observables we take the differential cross sections for fermion-pair production at a 0.5-1 TeV electron-positron linear collider with both beams longitudinally polarized. For the four-fermion contact interaction, we assume a general linear combination of the individual models with definite chiralities, with arbitrary coupling constants. In this sense, the estimated identification reach on the ADD model can be considered as 'model independent'. In the analysis, we give estimates also for the expected ''discovery reaches'' on the various scenarios. We emphasize the substantial role of beams polarization in enhancing the sensitivity to the contactlike interactions under consideration

  6. Largely Improved Near-Infrared Silicon-Photosensing by the Piezo-Phototronic Effect.

    Science.gov (United States)

    Dai, Yejing; Wang, Xingfu; Peng, Wenbo; Zou, Haiyang; Yu, Ruomeng; Ding, Yong; Wu, Changsheng; Wang, Zhong Lin

    2017-07-25

    Although silicon (Si) devices are the backbone of modern (opto-)electronics, infrared Si-photosensing suffers from low-efficiency due to its limitation in light-absorption. Here, we demonstrate a large improvement in the performance, equivalent to a 366-fold enhancement in photoresponsivity, of a Si-based near-infrared (NIR) photodetector (PD) by introducing the piezo-phototronic effect via a deposited CdS layer. By externally applying a -0.15‰ compressive strain to the heterojunction, carrier-dynamics modulation at the local junction can be induced by the piezoelectric polarization, and the photoresponsivity and detectivity of the PD exhibit an enhancement of two orders of magnitude, with the peak values up to 19.4 A/W and 1.8 × 10 12 cm Hz 1/2 /W, respectively. The obtained maximum responsivity is considerably larger than those of commercial Si and InGaAs PDs in the NIR waveband. Meanwhile, the rise time and fall time are reduced by 84.6% and 76.1% under the external compressive strain. This work provides a cost-effective approach to achieve high-performance NIR photosensing by the piezo-phototronic effect for high-integration Si-based optoelectronic systems.

  7. Divalent Metal Ion Transport across Large Biological Ion Channels and Their Effect on Conductance and Selectivity

    Directory of Open Access Journals (Sweden)

    Elena García-Giménez

    2012-01-01

    Full Text Available Electrophysiological characterization of large protein channels, usually displaying multi-ionic transport and weak ion selectivity, is commonly performed at physiological conditions (moderate gradients of KCl solutions at decimolar concentrations buffered at neutral pH. We extend here the characterization of the OmpF porin, a wide channel of the outer membrane of E. coli, by studying the effect of salts of divalent cations on the transport properties of the channel. The regulation of divalent cations concentration is essential in cell metabolism and understanding their effects is of key importance, not only in the channels specifically designed to control their passage but also in other multiionic channels. In particular, in porin channels like OmpF, divalent cations modulate the efficiency of molecules having antimicrobial activity. Taking advantage of the fact that the OmpF channel atomic structure has been resolved both in water and in MgCl2 aqueous solutions, we analyze the single channel conductance and the channel selectivity inversion aiming to separate the role of the electrolyte itself, and the counterion accumulation induced by the protein channel charges and other factors (binding, steric effects, etc. that being of minor importance in salts of monovalent cations become crucial in the case of divalent cations.

  8. Effect, Feasibility, and Clinical Relevance of Cell Enrichment in Large Volume Fat Grafting

    DEFF Research Database (Denmark)

    Rasmussen, Bo Sonnich; Lykke Sørensen, Celine; Vester-Glowinski, Peter Viktor

    2017-01-01

    Large volume fat grafting is limited by unpredictable volume loss; therefore, methods of improving graft retention have been developed. Fat graft enrichment with either stromal vascular fraction (SVF) cells or adipose tissue-derived stem/stromal cells (ASCs) has been investigated in several animal...... and human studies, and significantly improved graft retention has been reported. Improvement of graft retention and the feasibility of these techniques are equally important in evaluating the clinical relevance of cell enrichment. We conducted a systematic search of PubMed to identify studies on fat graft...... enrichment that used either SVF cells or ASCs, and only studies reporting volume assessment were included. A total of 38 articles (15 human and 23 animal) were included to investigate the effects of cell enrichment on graft retention as well as the feasibility and clinical relevance of cell-enriched fat...

  9. Effect of air gap on uniformity of large-scale surface-wave plasma

    International Nuclear Information System (INIS)

    Lan Chaohui; Hu Xiwei; Jiang Zhonghe; Liu Minghai

    2009-01-01

    The effect of air gap on the uniformity of large-scale surface-wave plasma (SWP) in a rectangular chamber device is studied by using three-dimensional numerical analyses based on the finite difference time-domain (FDTD) approximation to Maxwell's equations and plasma fluid model. The spatial distributions of surface wave excited by slot-antenna array and the plasma parameters such as electron density and temperature are presented. For different air gap thicknesses, the results show that the existence of air gap would severely weaken the excitations of the surface wave and thereby the SWP. Thus the air gap should be eliminated completely in the design of the SWP source, which is opposite to the former research results. (authors)

  10. Desorption of large molecules with light-element clusters: Effects of cluster size and substrate nature

    Energy Technology Data Exchange (ETDEWEB)

    Delcorte, Arnaud, E-mail: arnaud.delcorte@uclouvain.be [Institute of Condensed Matter and Nanosciences - Bio and Soft Matter, Universite catholique de Louvain, Croix du Sud, 1 bte 3, B-1348 Louvain-la-Neuve (Belgium); Garrison, Barbara J. [Department of Chemistry, Penn State University, University Park, PA 16802 (United States)

    2011-07-15

    This contribution focuses on the conditions required to desorb a large hydrocarbon molecule using light-element clusters. The test molecule is a 7.5 kDa coil of polystyrene (PS61). Several projectiles are compared, from C{sub 60} to 110 kDa organic droplets and two substrates are used, amorphous polyethylene and mono-crystalline gold. Different aiming points and incidence angles are examined. Under specific conditions, 10 keV nanodrops can desorb PS61 intact from a gold substrate and from a soft polyethylene substrate. The prevalent mechanism for the desorption of intact and 'cold' molecules is one in which the molecules are washed away by the projectile constituents and entrained in their flux, with an emission angle close to {approx}70 deg. The effects of the different parameters on the dynamics and the underlying physics are discussed in detail and the predictions of the model are compared with other published studies.

  11. Desorption of large molecules with light-element clusters: Effects of cluster size and substrate nature

    International Nuclear Information System (INIS)

    Delcorte, Arnaud; Garrison, Barbara J.

    2011-01-01

    This contribution focuses on the conditions required to desorb a large hydrocarbon molecule using light-element clusters. The test molecule is a 7.5 kDa coil of polystyrene (PS61). Several projectiles are compared, from C 60 to 110 kDa organic droplets and two substrates are used, amorphous polyethylene and mono-crystalline gold. Different aiming points and incidence angles are examined. Under specific conditions, 10 keV nanodrops can desorb PS61 intact from a gold substrate and from a soft polyethylene substrate. The prevalent mechanism for the desorption of intact and 'cold' molecules is one in which the molecules are washed away by the projectile constituents and entrained in their flux, with an emission angle close to ∼70 deg. The effects of the different parameters on the dynamics and the underlying physics are discussed in detail and the predictions of the model are compared with other published studies.

  12. Order of magnetic transition and large magnetocaloric effect in Er3Co

    International Nuclear Information System (INIS)

    Jun, Shen; Jian-Feng, Wu; Jin-Liang, Zhao; Feng-Xia, Hu; Ji-Rong, Sun; Bao-Gen, Shen

    2010-01-01

    We have studied the magnetic and magnetocaloric properties of the Er 3 Co compound, which undergoes ferromagnetic ordering below the Curie temperature T C = 13 K. It is found by fitting the isothermal magnetization curves that the Landau model is appropriate to describe the Er 3 Co compound. The giant magnetocaloric effect (MCE) without hysteresis loss around T C is found to result from the second-order ferromagnetic-to-paramagnetic transition. The maximal value of magnetic entropy change is 24.5 J/kg·K with a refrigerant capacity (RC) value of 476 J/kg for a field change of 0–5 T. Large reversible MEC and RC indicate the potentiality of Er 3 Co as a candidate magnetic refrigerant at low temperatures. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  13. The Effects of Topology on Throughput Capacity of Large Scale Wireless Networks

    Directory of Open Access Journals (Sweden)

    Qiuming Liu

    2017-03-01

    Full Text Available In this paper, we jointly consider the inhomogeneity and spatial dimension in large scale wireless networks. We study the effects of topology on the throughput capacity. This problem is inherently difficult since it is complex to handle the interference caused by simultaneous transmission. To solve this problem, we, according to the inhomogeneity of topology, divide the transmission into intra-cluster transmission and inter-cluster transmission. For the intra-cluster transmission, a spheroidal percolation model is constructed. The spheroidal percolation model guarantees a constant rate when a power control strategy is adopted. We also propose a cube percolation mode for the inter-cluster transmission. Different from the spheroidal percolation model, a constant transmission rate can be achieved without power control. For both transmissions, we propose a routing scheme with five phases. By comparing the achievable rate of each phase, we get the rate bottleneck, which is the throughput capacity of the network.

  14. Large N non-perturbative effects in N=4 superconformal Chern-Simons theories

    International Nuclear Information System (INIS)

    Hatsuda, Yasuyuki; Honda, Masazumi; Okuyama, Kazumi

    2015-07-01

    We investigate the large N instanton effects of partition functions in a class of N = 4 circular quiver Chern-Simons theories on a three-sphere. Our analysis is based on the supersymmetry localization and the Fermi-gas formalism. The resulting matrix model can be regarded as a two-parameter deformation of the ABJM matrix model, and has richer non-perturbative structures. Based on a systematic semi-classical analysis, we find analytic expressions of membrane instanton corrections. We also exactly compute the partition function for various cases and find some exact forms of worldsheet instanton corrections, which appear as quantum mechanical non-perturbative corrections in the Fermi-gas system.

  15. Effect of large aspect ratio of biomass particles on carbon burnout in a utility boiler

    Energy Technology Data Exchange (ETDEWEB)

    D. Gera; M.P. Mathur; M.C. Freeman; Allen Robinson [Fluent, Inc./NETL, Morgantown, WV (United States)

    2002-12-01

    This paper reports on the development and validation of comprehensive combustion sub models that include the effect of large aspect ratio of biomass (switchgrass) particles on carbon burnout and temperature distribution inside the particles. Temperature and carbon burnout data are compared from two different models that are formulated by assuming (i) the particles are cylindrical and conduct heat internally, and (ii) the particles are spherical without internal heat conduction, i.e., no temperature gradient exists inside the particle. It was inferred that the latter model significantly underpredicted the temperature of the particle and, consequently, the burnout. Additionally, some results from cofiring biomass (10% heat input) with pulverized coal (90% heat input) are compared with the pulverized coal (100% heat input) simulations and coal experiments in a tangentially fired 150 MW{sub e} utility boiler. 26 refs., 7 figs., 4 tabs.

  16. Trauma-induced "Macklin effect" with pneumothorax and large pneumomediastinum, disguised by allergy.

    Science.gov (United States)

    Di Saverio, Salomone; Kawamukai, Kenji; Biscardi, Andrea; Villani, Silvia; Zucchini, Luca; Tugnoli, Gregorio

    2013-09-01

    A 56-year-old man presented spontaneously to the Emergency Department complaining of facial and neck oedema after assumption of nonsteroidal anti-inflammatory drugs (NSAIDS). The triage nurse assigned the patient to Accident & Emergency (A&E) doctor as probable allergic reaction to NSAIDS. Chest X-ray (CXR), ordered after 24 hours, revealed a huge subcutaneous chest and neck emphysema without clearly visible pneumothorax. Subsequent chest CT scan showed a small left pneumothorax and a large amount of air in the mediastinum. The patient was conservatively treated since he was eupnoeic and hemodynamically stable. The pathophysiology of pneumomediastinum was first described by Macklin in 1939. The Macklin effect involves alveolar ruptures with air dissection along bronchovascular sheaths to the mediastinum. In this case the patient did not report in his history a recent blunt thoracic trauma and the initial suspicion of an allergic reaction has prevented physicians to immediately achieve the correct diagnosis.

  17. Sonoporation at Small and Large Length Scales: Effect of Cavitation Bubble Collapse on Membranes.

    Science.gov (United States)

    Fu, Haohao; Comer, Jeffrey; Cai, Wensheng; Chipot, Christophe

    2015-02-05

    Ultrasound has emerged as a promising means to effect controlled delivery of therapeutic agents through cell membranes. One possible mechanism that explains the enhanced permeability of lipid bilayers is the fast contraction of cavitation bubbles produced on the membrane surface, thereby generating large impulses, which, in turn, enhance the permeability of the bilayer to small molecules. In the present contribution, we investigate the collapse of bubbles of different diameters, using atomistic and coarse-grained molecular dynamics simulations to calculate the force exerted on the membrane. The total impulse can be computed rigorously in numerical simulations, revealing a superlinear dependence of the impulse on the radius of the bubble. The collapse affects the structure of a nearby immobilized membrane, and leads to partial membrane invagination and increased water permeation. The results of the present study are envisioned to help optimize the use of ultrasound, notably for the delivery of drugs.

  18. Mapping resistance to powdery mildew in barley reveals a large-effect nonhost resistance QTL.

    Science.gov (United States)

    Romero, Cynara C T; Vermeulen, Jasper P; Vels, Anton; Himmelbach, Axel; Mascher, Martin; Niks, Rients E

    2018-05-01

    Resistance factors against non-adapted powdery mildews were mapped in barley. Some QTLs seem effective only to non-adapted mildews, while others also play a role in defense against the adapted form. The durability and effectiveness of nonhost resistance suggests promising practical applications for crop breeding, relying upon elucidation of key aspects of this type of resistance. We investigated which genetic factors determine the nonhost status of barley (Hordeum vulgare L.) to powdery mildews (Blumeria graminis). We set out to verify whether genes involved in nonhost resistance have a wide effectiveness spectrum, and whether nonhost resistance genes confer resistance to the barley adapted powdery mildew. Two barley lines, SusBgt SC and SusBgt DC , with some susceptibility to the wheat powdery mildew B. graminis f.sp. tritici (Bgt) were crossed with cv Vada to generate two mapping populations. Each population was assessed for level of infection against four B. graminis ff.spp, and QTL mapping analyses were performed. Our results demonstrate polygenic inheritance for nonhost resistance, with some QTLs effective only to non-adapted mildews, while others play a role against adapted and non-adapted forms. Histology analyses of nonhost interaction show that most penetration attempts are stopped in association with papillae, and also suggest independent layers of defence at haustorium establishment and conidiophore formation. Nonhost resistance of barley to powdery mildew relies mostly on non-hypersensitive mechanisms. A large-effect nonhost resistance QTL mapped to a 1.4 cM interval is suitable for map-based cloning.

  19. Polarization-maintaining performance of large effective area, higher order modes fiber in a coiled configuration

    Science.gov (United States)

    Ahmad, Raja; Nicholson, Jeffrey W.; Abedin, Kazi S.; Westbrook, Paul S.; Headley, Clifford; Wisk, Patrick W.; Monberg, Eric M.; Yan, Man F.; DiGiovanni, David J.

    2018-02-01

    Scaling the power-level of fiber sources has many practical advantages, while also enabling fundamental studies on the light-matter interaction in amorphous guiding media. In order to scale the power-level of fiber-sources without encountering nonlinear impairments, a strategy is to increase the effective-area of the guided optical-mode. Increasing the effective-area of the fundamental mode in a fiber, however, presents the challenges of increased susceptibility to mode-distortion and effective-area-reduction under the influence of bends. Therefore, higher-order-mode (HOM) fibers, which guide light in large effective-area (Aeff) Bessel-like modes, are a good candidate for scaling the power-level of robust fiber-sources. Many applications of high-power fiber-sources also demand a deterministic control on the polarization-state of light. Furthermore, a polarization-maintaining (PM)-type HOM fiber can afford the added possibility of coherent-beam combination and polarization multiplexing of high-power fiber-lasers. Previously, we reported polarization-maintaining operation in a 1.3 m length of PM-HOM fiber that was held straight. The PM-HOM fiber guided Bessel-like modes with Aeff ranging from 1200-2800 μm2. In this work, we report, for the first time, that the polarization-extinction-ratio (PER) of the HOM exceeds 10 dB in an 8 m long fiber that is coiled down to a diameter of 40 cm. This opens a path towards compact and polarization-controlled high-power fiber-systems.

  20. Large grazers modify effects of aboveground-belowground interactions on small-scale plant community composition

    NARCIS (Netherlands)

    Veen, G. F. (Ciska); Geuverink, Elzemiek; Olff, Han; Schmid, Bernhard

    Aboveground and belowground organisms influence plant community composition by local interactions, and their scale of impact may vary from millimeters belowground to kilometers aboveground. However, it still poorly understood how large grazers that select their forage on large spatial scales

  1. Large grazers modify effects of aboveground–belowground interactions on small-scale plant community composition

    NARCIS (Netherlands)

    Veen, G.F.; Geuverink, E.; Olff, H.

    2012-01-01

    Aboveground and belowground organisms influence plant community composition by local interactions, and their scale of impact may vary from millimeters belowground to kilometers aboveground. However, it still poorly understood how large grazers that select their forage on large spatial scales

  2. Large Eddy Simulation and the effect of the turbulent inlet conditions in the mixing Tee

    International Nuclear Information System (INIS)

    Ndombo, Jean-Marc; Howard, Richard J.A.

    2011-01-01

    Highlights: → LES of Tee junctions can easily reproduce the bulk flow. → The presence or absence of a turbulent inlet condition has an affect on the wall heat transfer. → The maximum heat transfer moves 1 cm and reduces by 10% when a turbulent inlet is used. - Abstract: Thermal fatigue in Pressurized Water Reactor plants has been found to be very acute in some hot/cold Tee junction mixing zones. Large Eddy Simulation (LES) can be used to capture the unsteadiness which is responsible for the large mechanical stresses associated with thermal fatigue. Here one LES subgrid model is studied, namely the Dynamic Smagorinsky model. This paper has two goals. The first is to demonstrate some results obtained using the EDF R and D Code Saturne applied to the Vattenfall Tee junction benchmark (version 2006) and the second is to look at the effect of including synthetic turbulence at the Tee junction pipe inlets. The last goal is the main topic of this paper. The Synthetic Eddy Method is used to create the turbulent inlet conditions and is applied to two kinds of grids. One contains six million cells and the other ten million. The addition of turbulence at the inlet does not seem to have much effect on the bulk flow and all computations are in good agreement with the experimental data. However, the inlet turbulence does have an effect on the near wall flow. All cases show that the wall temperature fluctuation and the wall temperature/velocity correlation are not the same when a turbulent inlet condition is used. Inclusion of the turbulent inlet condition moves the downstream location of the maximum temperature/velocity correlation by 1 cm and reduces its magnitude by 10%. This result is very important because the temperature/velocity correlation is closely related to the turbulent heat transfer in the flow, which is in turn responsible for the mechanical stresses on the structure. Finally we have studied in detail the influence of the turbulent inlet condition just

  3. Effects of thin-layer boilover on flame geometry and dynamics in large hydrocarbon pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Ferrero, Fabio; Munoz, Miguel; Arnaldos, Josep [Centre d' Estudis del Risc Tecnologic (CERTEC), Chemical Engineering Department, Universitat Politecnica de Catalunya, Diagonal 647, 08028-Barcelona, Catalonia (Spain)

    2007-03-15

    This work aims to estimate the effects of thin-layer boilover on flame geometry and dynamics. A series of large scale experiments (in pools ranging from 1.5 to 6 m in diameter) were performed using gasoline and diesel as fuel. As expected, only diesel showed evidence of this phenomenon. This article presents a summary of the results obtained for flame height, tilt and pulsation. Flame height increases during water ebullition, though the increase is no longer detectable when wind speed exceeds certain values. Correlations previously presented in the literature to predict flame length and tilt were modified in order to fit the results obtained during thin-layer boilover. However, the influence on flame tilt is not as great and the equations for the stationary period seem suitable for the entire fire. Results of flame pulsation during the stationary period fill the gap in the literature for fires between 1.5 and 6 m and fit previous correlations. On the other hand, during ebullition, the flame pulsates faster, as air entrainment is greater and, as one would expect, this effect decreases with pool size. A new equation for estimating pulsation frequency during boilover is proposed. (author)

  4. Effect of stable stratification on dispersion within urban street canyons: A large-eddy simulation

    Science.gov (United States)

    Li, Xian-Xiang; Britter, Rex; Norford, Leslie K.

    2016-11-01

    This study employs a validated large-eddy simulation (LES) code with high tempo-spatial resolution to investigate the effect of a stably stratified roughness sublayer (RSL) on scalar transport within an urban street canyon. The major effect of stable stratification on the flow and turbulence inside the street canyon is that the flow slows down in both streamwise and vertical directions, a stagnant area near the street level emerges, and the vertical transport of momentum is weakened. Consequently, the transfer of heat between the street canyon and overlying atmosphere also gets weaker. The pollutant emitted from the street level 'pools' within the lower street canyon, and more pollutant accumulates within the street canyon with increasing stability. Under stable stratification, the dominant mechanism for pollutant transport within the street canyon has changed from ejections (flow carries high-concentration pollutant upward) to unorganized motions (flow carries high-concentration pollutant downward), which is responsible for the much lower dispersion efficiency under stable stratifications.

  5. Demand for mini cars and large cars; decay effects, and gasoline demand in Japan

    International Nuclear Information System (INIS)

    Bonilla, David; Schmitz, Klaus E.; Akisawa, Atsushi

    2012-01-01

    This article explains why: (a) consumers underinvest in new car fuel economy by opting to buy large vehicles; (b) macro shifts in vehicle classes have occurred in the last decades; and how (c) the effects of vehicle fuel economy and shifts in vehicle type influence the growth path of gasoline demand, which is the key to designing effective energy efficiency goals for transport. From 2008, 1.9 EXJ (Exajoules) of energy were consumed in Japan by private vehicles producing 124 MtCO 2 emissions. For the period 1980 to 2008, we estimated: (1) gasoline demand for three vehicle sizes; (2) vehicle sales; (3) new car fuel economy changes (the ‘real’ technical change); and (4) vehicle stocks. Using a data sample for 1980–2008 we found that: (a) in the short term consumers buy fuel economy, that is sales of mini and small cars increase, but this is not sustained in the long term: and (b) consumers increasingly traded in their cars for larger cars. A further finding was that gasoline demand is projected to increase to 2.3 EXJ by 2035, even with a growing number of mini cars. The policy implication is clear: Japan’s policy to reduce oil dependency to 80% by 2030 is in peril as long as buyers prefer larger cars and drive ever longer distances.

  6. Primordial Magnetic Field Effects on the CMB and Large-Scale Structure

    Directory of Open Access Journals (Sweden)

    Dai G. Yamazaki

    2010-01-01

    Full Text Available Magnetic fields are everywhere in nature, and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the turbulent high-temperature environment of the big bang. Such a primordial magnetic field (PMF would be expected to manifest itself in the cosmic microwave background (CMB temperature and polarization anisotropies, and also in the formation of large-scale structure. In this paper, we summarize the theoretical framework which we have developed to calculate the PMF power spectrum to high precision. Using this formulation, we summarize calculations of the effects of a PMF which take accurate quantitative account of the time evolution of the cutoff scale. We review the constructed numerical program, which is without approximation, and an improvement over the approach used in a number of previous works for studying the effect of the PMF on the cosmological perturbations. We demonstrate how the PMF is an important cosmological physical process on small scales. We also summarize the current constraints on the PMF amplitude Bλ and the power spectral index nB which have been deduced from the available CMB observational data by using our computational framework.

  7. Effects of Erythropoietin Administration on Adrenal Glands of Landrace/Large White Pigs after Ventricular Fibrillation

    Directory of Open Access Journals (Sweden)

    Armando Faa

    2016-01-01

    Full Text Available Aim. To evaluate the effects of erythropoietin administration on the adrenal glands in a swine model of ventricular fibrillation and resuscitation. Methods. Ventricular fibrillation was induced via pacing wire forwarded into the right ventricle in 20 female Landrace/Large White pigs, allocated into 2 groups: experimental group treated with bolus dose of erythropoietin (EPO and control group which received normal saline. Cardiopulmonary resuscitation (CPR was performed immediately after drug administration as per the 2010 European Resuscitation Council (ERC guidelines for Advanced Life Support (ALS until return of spontaneous circulation (ROSC or death. Animals who achieved ROSC were monitored, mechanically ventilated, extubated, observed, and euthanized. At necroscopy, adrenal glands samples were formalin-fixed, paraffin-embedded, and routinely processed. Sections were stained with hematoxylin-eosin. Results. Oedema and apoptosis were the most frequent histological changes and were detected in all animals in the adrenal cortex and in the medulla. Mild and focal endothelial lesions were also detected. A marked interindividual variability in the degree of the intensity of apoptosis and oedema at cortical and medullary level was observed within groups. Comparing the two groups, higher levels of pathological changes were detected in the control group. No significant difference between the two groups was observed regarding the endothelial changes. Conclusions. In animals exposed to ventricular fibrillation, EPO treatment has protective effects on the adrenal gland.

  8. Vascular legacy: HOPE ADVANCEs to EMPA-REG and LEADER: A Surprising similarity

    Directory of Open Access Journals (Sweden)

    Sanjay Kalra

    2017-01-01

    Full Text Available Recently reported cardiovascular outcome studies on empagliflozin (EMPA-REG and liraglutide (LEADER have spurred interest in this field of diabetology. This commentary compares and contrasts these studies with two equally important outcome trials conducted using blood pressure lowering agents. A comparison with MICROHOPE (using ramipril and ADVANCE (using perindopril + indapamide blood pressure arms throws up interesting facts. The degree of blood pressure lowering, dissociation between cardiovascular and cerebrovascular benefits, and discordance between renal and retinal outcomes are surprisingly similar in these trials, conducted using disparate molecules. The time taken to achieve such benefits is similar for all drugs except empagliflozin. Such discussion helps inform rational and evidence-based choice of therapy and forms the framework for future research.

  9. Probing Critical Point Energies of Transition Metal Dichalcogenides: Surprising Indirect Gap of Single Layer WSe 2

    KAUST Repository

    Zhang, Chendong

    2015-09-21

    By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.

  10. Probing Critical Point Energies of Transition Metal Dichalcogenides: Surprising Indirect Gap of Single Layer WSe 2

    KAUST Repository

    Zhang, Chendong; Chen, Yuxuan; Johnson, Amber; Li, Ming-yang; Li, Lain-Jong; Mende, Patrick C.; Feenstra, Randall M.; Shih, Chih Kang

    2015-01-01

    By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.

  11. Surprising judgments about robot drivers: Experiments on rising expectations and blaming humans

    Directory of Open Access Journals (Sweden)

    Peter Danielson

    2015-05-01

    Full Text Available N-Reasons is an experimental Internet survey platform designed to enhance public participation in applied ethics and policy. N-Reasons encourages individuals to generate reasons to support their judgments, and groups to converge on a common set of reasons pro and con various issues.  In the Robot Ethics Survey some of the reasons contributed surprising judgments about autonomous machines. Presented with a version of the trolley problem with an autonomous train as the agent, participants gave unexpected answers, revealing high expectations for the autonomous machine and shifting blame from the automated device to the humans in the scenario. Further experiments with a standard pair of human-only trolley problems refine these results. While showing the high expectations even when no autonomous machine is involved, human bystanders are only blamed in the machine case. A third experiment explicitly aimed at responsibility for driverless cars confirms our findings about shifting blame in the case of autonomous machine agents. We conclude methodologically that both results point to the power of an experimental survey based approach to public participation to explore surprising assumptions and judgments in applied ethics. However, both results also support using caution when interpreting survey results in ethics, demonstrating the importance of qualitative data to provide further context for evaluating judgments revealed by surveys. On the ethics side, the result about shifting blame to humans interacting with autonomous machines suggests caution about the unintended consequences of intuitive principles requiring human responsibility.http://dx.doi.org/10.5324/eip.v9i1.1727

  12. Effects of mud supply on large-scale estuary morphology and development over centuries to millennia

    Directory of Open Access Journals (Sweden)

    L. Braat

    2017-10-01

    Full Text Available Alluvial river estuaries consist largely of sand but are typically flanked by mudflats and salt marshes. The analogy with meandering rivers that are kept narrower than braided rivers by cohesive floodplain formation raises the question of how large-scale estuarine morphology and the late Holocene development of estuaries are affected by cohesive sediment. In this study we combine sand and mud transport processes and study their interaction effects on morphologically modelled estuaries on centennial to millennial timescales. The numerical modelling package Delft3D was applied in 2-DH starting from an idealised convergent estuary. The mixed sediment was modelled with an active layer and storage module with fluxes predicted by the Partheniades–Krone relations for mud and Engelund–Hansen for sand. The model was subjected to a range of idealised boundary conditions of tidal range, river discharge, waves and mud input. The model results show that mud is predominantly stored in mudflats on the side of the estuary. Marine mud supply only influences the mouth of the estuary, whereas fluvial mud is distributed along the whole estuary. Coastal waves stir up mud and remove the tendency to form muddy coastlines and the formation of mudflats in the downstream part of the estuary. Widening continues in estuaries with only sand, while mud supply leads to a narrower constant width and reduced channel and bar dynamics. This self-confinement eventually leads to a dynamic equilibrium in which lateral channel migration and mudflat expansion are balanced on average. However, for higher mud concentrations, higher discharge and low tidal amplitude, the estuary narrows and fills to become a tidal delta.

  13. Up-Regulatory Effects of Curcumin on Large Conductance Ca2+-Activated K+ Channels

    Science.gov (United States)

    Hei, Hongya; Li, Fangping; Wang, Yunman; Peng, Wen; Zhang, Xuemei

    2015-01-01

    Large conductance Ca2+-activated potassium channels (BK) are targets for research that explores therapeutic means to various diseases, owing to the roles of the channels in mediating multiple physiological processes in various cells and tissues. We investigated the pharmacological effects of curcumin, a compound isolated from the herb Curcuma longa, on BK channels. As recorded by whole-cell patch-clamp, curcumin increased BK (α) and BK (α+β1) currents in transfected HEK293 cells as well as the current density of BK in A7r5 smooth muscle cells in a dose-dependent manner. By incubating with curcumin for 24 hours, the current density of exogenous BK (α) in HEK293 cells and the endogenous BK in A7r5 cells were both enhanced notably, though the steady-state activation of the channels did not shift significantly, except for BK (α+β1). Curcumin up-regulated the BK protein expression without changing its mRNA level in A7r5 cells. The surface expression and the half-life of BK channels were also increased by curcumin in HEK293 cells. These effects of curcumin were abolished by MG-132, a proteasome inhibitor. Curcumin also increased ERK 1/2 phosphorylation, while inhibiting ERK by U0126 attenuated the curcumin-induced up-regulation of BK protein expression. We also observed that the curcumin-induced relaxation in the isolated rat aortic rings was significantly attenuated by paxilline, a BK channel specific blocker. These results show that curcumin enhances the activity of the BK channels by interacting with BK directly as well as enhancing BK protein expression through inhibiting proteasomal degradation and activating ERK signaling pathway. The findings suggest that curcumin is a potential BK channel activator and provide novel insight into its complicated pharmacological effects and the underlying mechanisms. PMID:26672753

  14. Up-Regulatory Effects of Curcumin on Large Conductance Ca2+-Activated K+ Channels.

    Directory of Open Access Journals (Sweden)

    Qijing Chen

    Full Text Available Large conductance Ca2+-activated potassium channels (BK are targets for research that explores therapeutic means to various diseases, owing to the roles of the channels in mediating multiple physiological processes in various cells and tissues. We investigated the pharmacological effects of curcumin, a compound isolated from the herb Curcuma longa, on BK channels. As recorded by whole-cell patch-clamp, curcumin increased BK (α and BK (α+β1 currents in transfected HEK293 cells as well as the current density of BK in A7r5 smooth muscle cells in a dose-dependent manner. By incubating with curcumin for 24 hours, the current density of exogenous BK (α in HEK293 cells and the endogenous BK in A7r5 cells were both enhanced notably, though the steady-state activation of the channels did not shift significantly, except for BK (α+β1. Curcumin up-regulated the BK protein expression without changing its mRNA level in A7r5 cells. The surface expression and the half-life of BK channels were also increased by curcumin in HEK293 cells. These effects of curcumin were abolished by MG-132, a proteasome inhibitor. Curcumin also increased ERK 1/2 phosphorylation, while inhibiting ERK by U0126 attenuated the curcumin-induced up-regulation of BK protein expression. We also observed that the curcumin-induced relaxation in the isolated rat aortic rings was significantly attenuated by paxilline, a BK channel specific blocker. These results show that curcumin enhances the activity of the BK channels by interacting with BK directly as well as enhancing BK protein expression through inhibiting proteasomal degradation and activating ERK signaling pathway. The findings suggest that curcumin is a potential BK channel activator and provide novel insight into its complicated pharmacological effects and the underlying mechanisms.

  15. Tree-crown-resolving large-eddy simulation for evaluating greenery effects on urban heat environments

    Science.gov (United States)

    Matsuda, K.; Onishi, R.; Takahashi, K.

    2017-12-01

    Urban high temperatures due to the combined influence of global warming and urban heat islands increase the risk of heat stroke. Greenery is one of possible countermeasures for mitigating the heat environments since the transpiration and shading effect of trees can reduce the air temperature and the radiative heat flux. In order to formulate effective measures, it is important to estimate the influence of the greenery on the heat stroke risk. In this study, we have developed a tree-crown-resolving large-eddy simulation (LES) model that is coupled with three-dimensional radiative transfer (3DRT) model. The Multi-Scale Simulator for the Geoenvironment (MSSG) is used for performing building- and tree-crown-resolving LES. The 3DRT model is implemented in the MSSG so that the 3DRT is calculated repeatedly during the time integration of the LES. We have confirmed that the computational time for the 3DRT model is negligibly small compared with that for the LES and the accuracy of the 3DRT model is sufficiently high to evaluate the radiative heat flux at the pedestrian level. The present model is applied to the analysis of the heat environment in an actual urban area around the Tokyo Bay area, covering 8 km × 8 km with 5-m grid mesh, in order to confirm its feasibility. The results show that the wet-bulb globe temperature (WBGT), which is an indicator of the heat stroke risk, is predicted in a sufficiently high accuracy to evaluate the influence of tree crowns on the heat environment. In addition, by comparing with a case without the greenery in the Tokyo Bay area, we have confirmed that the greenery increases the low WBGT areas in major pedestrian spaces by a factor of 3.4. This indicates that the present model can predict the greenery effect on the urban heat environment quantitatively.

  16. Effects of Large Wood on River-Floodplain Connectivity in a Headwater Appalachian Stream

    Science.gov (United States)

    Keys, T.; Govenor, H.; Jones, C. N.; Hession, W. C.; Scott, D.; Hester, E. T.

    2017-12-01

    Large wood (LW) plays an important, yet often undervalued role in stream ecosystems. Traditionally, LW has been removed from streams for aesthetic, navigational, and flood mitigation purposes. However, extensive research over the last three decades has directly linked LW to critical ecosystem functions including habitat provisioning, stream geomorphic stability, and water quality improvements; and as such, LW has increasingly been implemented in stream restoration activities. One of the proposed benefits to this restoration approach is that LW increases river-floodplain connectivity, potentially decreasing downstream flood peaks and improving water quality. Here, we conducted two experiential floods (i.e., one with and one without LW) in a headwater, agricultural stream to explore the effect of LW on river-floodplain connectivity and resulting hydrodynamic processes. During each flood, we released an equal amount of water to the stream channel, measured stream discharge at upstream and downstream boundaries, and measured inundation depth at multiple locations across the floodplain. We then utilized a 2-dimensional hydrodynamic model (HEC-RAS) to simulate floodplain hydrodynamics. We first calibrated the model using observations from the two experimental floods. Then, we utilized the calibrated model to evaluate differing LW placement strategies and effects under various flow conditions. Results show that the addition of LW to the channel decreased channel velocity and increased inundation extent, inundation depth, and floodplain velocity. Differential placement of LW along the stream impacted the levels of floodplain discharge, primarily due to the geomorphic characteristics of the stream. Finally, we examined the effects of LW on floodplain hydrodynamics across a synthetic flow record, and found that the magnitude of river-floodplain connectivity decreased as recurrence interval increased, with limited impacts on storm events with a recurrence interval of 25 years

  17. On predicting quantal cross sections by interpolation: Surprisal analysis of j/sub z/CCS and statistical j/sub z/ results

    International Nuclear Information System (INIS)

    Goldflam, R.; Kouri, D.J.

    1976-01-01

    New methods for predicting the full matrix of integral cross sections are developed by combining the surprisal analysis of Bernstein and Levine with the j/sub z/-conserving coupled states method (j/sub z/CCS) of McGuire, Kouri, and Pack and with the statistical j/sub z/ approximation (Sj/sub z/) of Kouri, Shimoni, and Heil. A variety of approaches is possible and only three are studied in the present work. These are (a) a surprisal fit of the j=0→j' column of the j/sub z/CCS cross section matrix (thereby requiring only a solution of the lambda=0 set of j/sub z/CCS equations), (b) a surprisal fit of the lambda-bar=0 Sj/sub z/ cross section matrix (again requiring solution of the lambda=0 set of j/sub z/CCS equations only), and (c) a surprisal fit of a lambda-bar not equal to 0 Sj/sub z/ submatrix (involving input cross sections for j,j'> or =lambda-bar transitions only). The last approach requires the solution of the lambda=lambda-bar set of j/sub z/CCS equations only, which requires less computation effort than the effective potential method. We explore three different choices for the prior and two-parameter (i.e., linear) and three-parameter (i.e., parabolic) fits as applied to Ar--N 2 collisions. The results are in general very encouraging and for one choice of prior give results which are within 20% of the exact j/sub z/CCS results

  18. Assessing cost-effectiveness of specific LID practice designs in response to large storm events

    Science.gov (United States)

    Chui, Ting Fong May; Liu, Xin; Zhan, Wenting

    2016-02-01

    Low impact development (LID) practices have become more important in urban stormwater management worldwide. However, most research on design optimization focuses on relatively large scale, and there is very limited information or guideline regarding individual LID practice designs (i.e., optimal depth, width and length). The objective of this study is to identify the optimal design by assessing the hydrological performance and the cost-effectiveness of different designs of LID practices at a household or business scale, and to analyze the sensitivity of the hydrological performance and the cost of the optimal design to different model and design parameters. First, EPA SWMM, automatically controlled by MATLAB, is used to obtain the peak runoff of different designs of three specific LID practices (i.e., green roof, bioretention and porous pavement) under different design storms (i.e., 2 yr and 50 yr design storms of Hong Kong, China and Seattle, U.S.). Then, life cycle cost is estimated for the different designs, and the optimal design, defined as the design with the lowest cost and at least 20% peak runoff reduction, is identified. Finally, sensitivity of the optimal design to the different design parameters is examined. The optimal design of green roof tends to be larger in area but thinner, while the optimal designs of bioretention and porous pavement tend to be smaller in area. To handle larger storms, however, it is more effective to increase the green roof depth, and to increase the area of the bioretention and porous pavement. Porous pavement is the most cost-effective for peak flow reduction, followed by bioretention and then green roof. The cost-effectiveness, measured as the peak runoff reduction/thousand Dollars of LID practices in Hong Kong (e.g., 0.02 L/103 US s, 0.15 L/103 US s and 0.93 L/103 US s for green roof, bioretention and porous pavement for 2 yr storm) is lower than that in Seattle (e.g., 0.03 L/103 US s, 0.29 L/103 US s and 1.58 L/103 US s for

  19. Effect of pore size on performance of monolithic tube chromatography of large biomolecules.

    Science.gov (United States)

    Podgornik, Ales; Hamachi, Masataka; Isakari, Yu; Yoshimoto, Noriko; Yamamoto, Shuichi

    2017-11-01

    Effect of pore size on the performance of ion-exchange monolith tube chromatography of large biomolecules was investigated. Radial flow 1 mL polymer based monolith tubes of different pore sizes (1.5, 2, and 6 μm) were tested with model samples such as 20 mer poly T-DNA, basic proteins, and acidic proteins (molecular weight 14 000-670 000). Pressure drop, pH transient, the number of binding site, dynamic binding capacity, and peak width were examined. Pressure drop-flow rate curves and dynamic binding capacity values were well correlated with the nominal pore size. While duration of the pH transient curves depends on the pore size, it was found that pH duration normalized on estimated surface area was constant, indicating that the ligand density is the same. This was also confirmed by the constant number of binding site values being independent of pore size. The peak width values were similar to those for axial flow monolith chromatography. These results showed that it is easy to scale up axial flow monolith chromatography to radial flow monolith tube chromatography by choosing the right pore size in terms of the pressure drop and capacity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Complex magnetic properties and large magnetocaloric effects in RCoGe (R=Tb, Dy compounds

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2018-05-01

    Full Text Available Complicated magnetic phase transitions and Large magnetocaloric effects (MCEs in RCoGe (R=Tb, Dy compounds have been reported in this paper. Results show that the TbCoGe compounds have a magnetic phase transition from antiferromagnetic to paramagnetic (AFM-PM at TN∼16 K, which is close to the value reported by neutron diffraction. The DyCoGe compound undergoes complicated phase changes from 2 K up to 300 K. The peak at 10 K displays a phase transition from antiferromagnetic to ferromagnetic (AFM-FM. In particular, a significant ferromagnetic to paramagnetic (FM-PM phase transition was found at the temperature as high as 175 K and the cusp becomes more abrupt with the magnetic field increasing from 0.01 T to 0.1 T. The maximum value of magnetic entropy change of TbCoGe and DyCoGe compounds achieve 14.5 J/kg K and 11.5 J/kg K respectively for a field change of 0-5 T. Additionally, the correspondingly considerable refrigerant capacity value of 260 J/kg and 242 J/kg are also obtained respectively, suggesting that both TbCoGe and DyCoGe compounds could be considered as good candidates for low temperature magnetic refrigerant.

  1. Large magnetocaloric effect of GdNiAl{sub 2} compound

    Energy Technology Data Exchange (ETDEWEB)

    Dembele, S.N.; Ma, Z.; Shang, Y.F. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Fu, H., E-mail: fuhao@uestc.edu.cn [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Balfour, E.A. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Hadimani, R.L.; Jiles, D.C. [Department of Electrical and Computer Engineering, Iowa State University, Ames, IA 50011 (United States); Ames Laboratory, US Department of Energy, Ames, IA 50011 (United States); Teng, B.H.; Luo, Y. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2015-10-01

    This paper presents the structure, magnetic properties, and magnetocaloric effect of the polycrystalline compound GdNiAl{sub 2}. Powder X-ray diffraction (XRD) measurement and Rietveld refinement revealed that GdNiAl{sub 2} alloy is CuMgAl{sub 2}-type phase structure with about 1 wt% GdNi{sub 2}Al{sub 3} secondary phase. Magnetic measurements suggest that the compound is ferromagnetic and undergoes a second-order phase transition near 28 K. The maximum value of magnetic entropy change reaches 16.0 J/kg K for an applied magnetic field change of 0–50 kOe and the relative cooling power was 6.4×10{sup 2} J/kg. It is a promising candidate as a magnetocaloric material working near liquid hydrogen temperature (~20 K) exhibiting large relative cooling power. - Highlights: • Preferred orientation with axis of [010] was found in the GdNiAl{sub 2} compound. • The ΔS{sub Mmax} and the RCP are 16.0 J/kg K and 640 J/kg, respectively, for ΔH=50 kOe. • Relative low rare earth content in GdNiAl{sub 2} comparing with other candidates.

  2. On the effect of numerical errors in large eddy simulations of turbulent flows

    International Nuclear Information System (INIS)

    Kravchenko, A.G.; Moin, P.

    1997-01-01

    Aliased and dealiased numerical simulations of a turbulent channel flow are performed using spectral and finite difference methods. Analytical and numerical studies show that aliasing errors are more destructive for spectral and high-order finite-difference calculations than for low-order finite-difference simulations. Numerical errors have different effects for different forms of the nonlinear terms in the Navier-Stokes equations. For divergence and convective forms, spectral methods are energy-conserving only if dealiasing is performed. For skew-symmetric and rotational forms, both spectral and finite-difference methods are energy-conserving even in the presence of aliasing errors. It is shown that discrepancies between the results of dealiased spectral and standard nondialiased finite-difference methods are due to both aliasing and truncation errors with the latter being the leading source of differences. The relative importance of aliasing and truncation errors as compared to subgrid scale model terms in large eddy simulations is analyzed and discussed. For low-order finite-difference simulations, truncation errors can exceed the magnitude of the subgrid scale term. 25 refs., 17 figs., 1 tab

  3. Effects of induced magnetic field on large scale pulsed MHD generator with two phase flow

    International Nuclear Information System (INIS)

    Ishikawa, M.; Koshiba, Y.; Matsushita, T.

    2004-01-01

    A large pulsed MHD generator 'SAKHALIN' was constructed in Russia (the former Soviet-Union) and operated with solid fuels. The 'SAKHALIN' with the channel length of 4.5 m could demonstrate the electric power output of 510 MW. The effects of induced magnetic field and two phase flow on the shock wave within the 'SAKHALIN' generator have been studied by time dependent, one dimensional analyses. It has been shown that the magnetic Reynolds number is about 0.58 for Run No. 1, and the induced magnetic flux density is about 20% at the entrance and exit of the MHD channel. The shock wave becomes stronger when the induced magnetic field is taken into account, when the operation voltage becomes low. The working gas plasma contains about 40% of liquid particles (Al 2 O 3 ) in weight, and the present analysis treats the liquid particles as another gas. In the case of mono-phase flow, the sharp shock wave is induced when the load voltage becomes small such as 500 V with larger Lorentz force, whereas in the case of two phase flow, the shock wave becomes less sharp because of the interaction with liquid particles

  4. [Effects of large-area planting water hyacinth on macro-benthos community structure and biomass].

    Science.gov (United States)

    Liu, Guo-Feng; Liu, Hai-Qin; Zhang, Zhi-Yong; Zhang, Ying-Ying; Yan, Shao-Hua; Zhong, Ji-Cheng; Fan, Cheng-Xin

    2010-12-01

    The effects on macro-benthos and benthos environment of planting 200 hm2 water hyacinth (E. crassipens) in Zhushan Bay, Lake Taihu, were studied during 8-10 months consecutive surveys. Results indicated that average densities of mollusca (the main species were Bellamya aeruginosa) in far-planting, near-planting and planting area were 276.67, 371.11 and 440.00 ind/m2, respectively, and biomass were 373.15, 486.57 and 672.54 g/m2, respectively, showed that average density and biomass of planting area's were higher than those of others. However, the average density and biomass of Oligochaeta (the main species was Limodrilus hoffmeisteri) and Chironomidae in planting area were lower than that of outside planting area. The density and biomass of three dominant species of benthic animal increased quickly during 8-9 months, decreased quickly in October inside and outside water hyacinth planting area. The reason of this phenomenon could be possible that lots of cyanobacteria cells died and consumed dissolve oxygen in proceed decomposing. Algae cells released lots of phosphorus and nitrogen simultaneously, so macro-benthos died in this environment. The indexes of Shannon-Weaver and Simpson indicated that water environment was in moderate polluted state. On the basis of the survey results, the large-area and high-density planting water hyacinth haven't demonstrated a great impact on macrobenthos and benthos environment in short planting time (about 6 months planting time).

  5. Principal shapes and squeezed limits in the effective field theory of large scale structure

    Energy Technology Data Exchange (ETDEWEB)

    Bertolini, Daniele; Solon, Mikhail P., E-mail: dbertolini@lbl.gov, E-mail: mpsolon@lbl.gov [Berkeley Center for Theoretical Physics, University of California, South Hall Road, Berkeley, CA, 94720 (United States)

    2016-11-01

    We apply an orthogonalization procedure on the effective field theory of large scale structure (EFT of LSS) shapes, relevant for the angle-averaged bispectrum and non-Gaussian covariance of the matter power spectrum at one loop. Assuming natural-sized EFT parameters, this identifies a linear combination of EFT shapes—referred to as the principal shape—that gives the dominant contribution for the whole kinematic plane, with subdominant combinations suppressed by a few orders of magnitude. For the covariance, our orthogonal transformation is in excellent agreement with a principal component analysis applied to available data. Additionally we find that, for both observables, the coefficients of the principal shapes are well approximated by the EFT coefficients appearing in the squeezed limit, and are thus measurable from power spectrum response functions. Employing data from N-body simulations for the growth-only response, we measure the single EFT coefficient describing the angle-averaged bispectrum with Ο (10%) precision. These methods of shape orthogonalization and measurement of coefficients from response functions are valuable tools for developing the EFT of LSS framework, and can be applied to more general observables.

  6. Effect of large volume paracentesis on plasma volume--a cause of hypovolemia

    International Nuclear Information System (INIS)

    Kao, H.W.; Rakov, N.E.; Savage, E.; Reynolds, T.B.

    1985-01-01

    Large volume paracentesis, while effectively relieving symptoms in patients with tense ascites, has been generally avoided due to reports of complications attributed to an acute reduction in intravascular volume. Measurements of plasma volume in these subjects have been by indirect methods and have not uniformly confirmed hypovolemia. We have prospectively evaluated 18 patients (20 paracenteses) with tense ascites and peripheral edema due to chronic liver disease undergoing 5 liter paracentesis for relief of symptoms. Plasma volume pre- and postparacentesis was assessed by a 125 I-labeled human serum albumin dilution technique as well as by the change in hematocrit and postural blood pressure difference. No significant change in serum sodium, urea nitrogen, hematocrit or postural systolic blood pressure difference was noted at 24 or 48 hr after paracentesis. Serum creatinine at 24 hr after paracentesis was unchanged but a small but statistically significant increase in serum creatinine was noted at 48 hr postparacentesis. Plasma volume changed -2.7% (n = 6, not statistically significant) during the first 24 hr and -2.8% (n = 12, not statistically significant) during the 0- to 48-hr period. No complications from paracentesis were noted. These results suggest that 5 liter paracentesis for relief of symptoms is safe in patients with tense ascites and peripheral edema from chronic liver disease

  7. Effect of Age on the Hemostatic Function in Patients with Degenerative Diseases of the Large Joints

    Directory of Open Access Journals (Sweden)

    Igor L. Shlykov, PhD¹, ScD¹

    2013-06-01

    Full Text Available Background: Aging is associated with an increased hypercoagulable state. Degenerative diseases of the large joints are also accompanied by increased coagulation activity. We investigated the effect of age on the hemostatic function in patients with osteoarthritis. Material and Methods: The study included 192 patients with osteoarthritis admitted to the clinic for primary hip or knee arthroplasty. The patients were categorized into 5 age groups: the age group under 40 years, the 41–to-50 -year age group, the 51–to-60-year age group, the 61-to-70- year age group, and the age group over 70 years. The general blood clotting tests, platelet number, fibrinogen, antithrombin, protein C, TAT, D-dimer, vonWillebrand factor (vWF, PAI-1, ß-thromboglobulin were determined. Results: Among patients with osteoarthritis, the antithrombin III level significantly decreased by the age of 50; however, above the age of 60 there was a distinct decrease in platelet count, and over the age of 70 the activity of the extrinsic coagulation pathway and the plasminogen level dropped significantly. TAT and D-dimer levels were elevated in most of the patients. Conclusion: The decrease in platelet count coupled with the activity of the extrinsic coagulation pathway in elderly osteoarthritic patients may increase blood loss during total arthroplasty; also, the drop in the anticoagulant and fibrinolytic potential may play a negative role in strengthening the prothrombotic state during the postoperative period.

  8. Effect, Feasibility, and Clinical Relevance of Cell Enrichment in Large Volume Fat Grafting: A Systematic Review.

    Science.gov (United States)

    Rasmussen, Bo Sonnich; Lykke Sørensen, Celine; Vester-Glowinski, Peter Viktor; Herly, Mikkel; Trojahn Kølle, Stig-Frederik; Fischer-Nielsen, Anne; Drzewiecki, Krzysztof Tadeusz

    2017-07-01

    Large volume fat grafting is limited by unpredictable volume loss; therefore, methods of improving graft retention have been developed. Fat graft enrichment with either stromal vascular fraction (SVF) cells or adipose tissue-derived stem/stromal cells (ASCs) has been investigated in several animal and human studies, and significantly improved graft retention has been reported. Improvement of graft retention and the feasibility of these techniques are equally important in evaluating the clinical relevance of cell enrichment. We conducted a systematic search of PubMed to identify studies on fat graft enrichment that used either SVF cells or ASCs, and only studies reporting volume assessment were included. A total of 38 articles (15 human and 23 animal) were included to investigate the effects of cell enrichment on graft retention as well as the feasibility and clinical relevance of cell-enriched fat grafting. Improvements in graft retention, the SVF to fat (SVF:fat) ratio, and the ASC concentration used for enrichment were emphasized. We proposed an increased retention rate greater than 1.5-fold relative to nonenriched grafts and a maximum SVF:fat ratio of 1:1 as the thresholds for clinical relevance and feasibility, respectively. Nine studies fulfilled these criteria, whereof 6 used ASCs for enrichment. We found no convincing evidence of a clinically relevant effect of SVF enrichment in humans. ASC enrichment has shown promising results in enhancing graft retention, but additional clinical trials are needed to substantiate this claim and also determine the optimal concentration of SVF cells/ASCs for enrichment. 4. © 2017 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  9. Large eddy simulation on the effect of free-stream turbulence on bypass transition

    International Nuclear Information System (INIS)

    Xu, Zhengqian; Zhao, Qingjun; Lin, Qizhao; Xu, Jianzhong

    2015-01-01

    Highlights: • Low-frequency dominant inflow leads to inner instability. • High-frequency mode is indispensable for inner instability. • Low-frequency mode highly affects the transition onset. • High-frequency mode highly affects the transition rate. • The frequency of laminar streaks is comparable with that of turbulent spot. - Abstract: The effect of free-stream turbulence (FST) on bypass transition in a zero-pressure-gradient boundary layer is investigated by means of Large Eddy Simulation (LES). The broadband turbulent inflow is synthesized to validate the feasibility of LES. Both a zero-thickness plate and one with super-ellipse leading-edge are addressed. The calculated Reynolds-averaged fields are compared with experimental data and decent agreement is achieved. Instantaneous fields show the instability occurs in the lifted low-speed streaks similar to earlier DNS results, which can be ascribed to outer mode. Various inflows with bi-/tri-mode interaction are specified to analyze effects of particular frequency mode on the instability pattern and multifarious transition or non-transition scenarios are obtained. Outer instability is observed in the cases with one low-frequency mode and one high-frequency mode inflow as reported by Zaki and Durbin (2005), and with one more high-frequency mode appended. Inner instability is observed in the case with a low-frequency dominant inflow, while the high-frequency mode is indispensable to induce the secondary instability. Furthermore, the results show that the transition onset is highly sensitive to low-frequency mode while the transition rate is highly sensitive to high-frequency mode. Finally, the formational frequency of turbulent spot (FFTS) is counted and the frequency of laminar streaks is demonstrated by spectral analysis

  10. THE TURN OF THE MONTH EFFECT CONTINUED: A COMPARISON OF SMALL CAP STOCKS AND LARGE CAP STOCKS

    OpenAIRE

    Ramsundhar, Shamman

    2010-01-01

    The purpose of this paper is to investigate whether the turn of the month effect occurs in small cap and large cap stocks and if it occurs in both categories, to determine whether there is a difference in the magnitude. My research, for the period of 1963-2008, based on the CRSP value weighted index, shows that there is a significant turn of the month effect in small and large cap stocks, however the effect is larger in small cap stocks. Furthermore, this effect is not limited to a short time...

  11. Short- and medium-term atmospheric constituent effects of very large solar proton events

    Directory of Open Access Journals (Sweden)

    C. H. Jackman

    2008-02-01

    Full Text Available Solar eruptions sometimes produce protons, which impact the Earth's atmosphere. These solar proton events (SPEs generally last a few days and produce high energy particles that precipitate into the Earth's atmosphere. The protons cause ionization and dissociation processes that ultimately lead to an enhancement of odd-hydrogen and odd-nitrogen in the polar cap regions (>60° geomagnetic latitude. We have used the Whole Atmosphere Community Climate Model (WACCM3 to study the atmospheric impact of SPEs over the period 1963–2005. The very largest SPEs were found to be the most important and caused atmospheric effects that lasted several months after the events. We present the short- and medium-term (days to a few months atmospheric influence of the four largest SPEs in the past 45 years (August 1972; October 1989; July 2000; and October–November 2003 as computed by WACCM3 and observed by satellite instruments. Polar mesospheric NOx (NO+NO2 increased by over 50 ppbv and mesospheric ozone decreased by over 30% during these very large SPEs. Changes in HNO3, N2O5, ClONO2, HOCl, and ClO were indirectly caused by the very large SPEs in October–November 2003, were simulated by WACCM3, and previously measured by Envisat Michelson Interferometer for Passive Atmospheric Sounding (MIPAS. WACCM3 output was also represented by sampling with the MIPAS averaging kernel for a more valid comparison. Although qualitatively similar, there are discrepancies between the model and measurement with WACCM3 predicted HNO3 and ClONO2 enhancements being smaller than measured and N2O5 enhancements being larger than measured. The HOCl enhancements were fairly similar in amounts and temporal variation in WACCM3 and MIPAS. WACCM3 simulated ClO decreases below 50 km, whereas MIPAS mainly observed increases, a very perplexing difference. Upper stratospheric

  12. Hillslope, river, and Mountain: some surprises in Landscape evolution (Ralph Alger Bagnold Medal Lecture)

    Science.gov (United States)

    Tucker, G. E.

    2012-04-01

    Geomorphology, like the rest of geoscience, has always had two major themes: a quest to understand the earth's history and 'products' - its landscapes and seascapes - and, in parallel, a quest to understand its formative processes. This dualism is manifest in the remarkable career of R. A. Bagnold, who was inspired by landforms such as dunes, and dedicated to understanding the physical processes that shaped them. His legacy inspires us to emulate two principles at the heart of his contributions: the benefits of rooting geomorphic theory in basic physics, and the importance of understanding geomorphic systems in terms of simple equations framed around energy or force. Today, following Bagnold's footsteps, the earth-surface process community is engaged in a quest to build, test, and refine an ever-improving body of theory to describe our planet's surface and its evolution. In this lecture, I review a small sample of some of the fruits of that quest, emphasizing the value of surprises encountered along the way. The first example involves models of long-term river incision into bedrock. When the community began to grapple with how to represent this process mathematically, several different ideas emerged. Some were based on the assumption that sediment transport is the limiting factor; others assumed that hydraulic stress on rock is the key, while still others treated rivers as first-order 'reactors.' Thanks in part to advances in digital topography and numerical computing, the predictions of these models can be tested using natural-experiment case studies. Examples from the King Range, USA, the Central Apennines, Italy, and the fold-thrust belt of Taiwan, illustrate that independent knowledge of history and/or tectonics makes it possible to quantify how the rivers have responded to external forcing. Some interesting surprises emerge, such as: that the relief-uplift relationship can be highly nonlinear in a steady-state landscape because of grain-entrainment thresholds

  13. Geomechanical effects of stress shadow created by large-scale destress blasting

    Directory of Open Access Journals (Sweden)

    Isaac Vennes

    2017-12-01

    Full Text Available This study aims to determine if large-scale choked panel destress blasting can provide sufficient beneficial stress reduction in highly-stressed remnant ore pillar that is planned for production. The orebody is divided into 20 stopes over 2 levels, and 2 panels are choke-blasted in the hanging wall to shield the ore pillar by creating a stress shadow around it. A linear-elastic model of the mining system is constructed with finite difference code FLAC3D. The effect of destress blasting in the panels is simulated by applying a fragmentation factor (α to the rock mass stiffness and a stress reduction factor (β to the current state of stress in the region occupied by the destress panels. As an extreme case, the destress panel is also modeled as a void to obtain the maximum possible beneficial effects of destressing and stress shadow. Four stopes are mined in the stress shadow of the panels in 6 lifts and then backfilled. The effect of destress blasting on the remnant ore pillar is quantified based on stress change and brittle shear ratio (BSR in the stress shadow zone compared to the base case without destress blasting. To establish realistic rock fragmentation and stress reduction factors, model results are compared to measured stress changes reported for case studies at Fraser and Brunswick mines. A 1.5 MPa immediate stress decrease was observed 20 m away from the panel at Fraser Mine, and a 4 MPa immediate stress decrease was observed 25 m away at Brunswick Mine. Comparable results are obtained from the current model with a rock fragmentation factor α of 0.2 and a stress reduction factor β of 0.8. It is shown that a destress blasting with these parameters reduces the major principal stress in the nearest stopes by 10–25 MPa. This yields an immediate reduction of BSR, which is deemed sufficient to reduce volume of ore at risk in the pillar.

  14. The (in)effectiveness of Global Land Policies on Large-Scale Land Acquisition

    NARCIS (Netherlands)

    Verhoog, S.M.

    2014-01-01

    Due to current crises, large-scale land acquisition (LSLA) is becoming a topic of growing concern. Public data from the ‘Land Matrix Global Observatory’ project (Land Matrix 2014a) demonstrates that since 2000, 1,664 large-scale land transactions in low- and middle-income countries were reported,

  15. Effect of plumes on measuring the large scale circulation in turbulent Rayleigh-Bénard convection

    NARCIS (Netherlands)

    Stevens, Richard Johannes Antonius Maria; Clercx, H.J.H.; Lohse, Detlef

    2011-01-01

    We studied the properties of the large-scale circulation (LSC) in turbulent Rayleigh-Bénard (RB) convection by using results from direct numerical simulations in which we placed a large number of numerical probes close to the sidewall. The LSC orientation is determined by either a cosine or a

  16. Effects of mud supply on large-scale estuary morphology and development over centuries to millennia

    NARCIS (Netherlands)

    Braat, L.; van Kessel, Thijs; Leuven, J.R.F.W.; Kleinhans, M.G.

    2017-01-01

    Alluvial river estuaries consist largely of sand but are typically flanked by mudflats and salt marshes. The analogy with meandering rivers that are kept narrower than braided rivers by cohesive floodplain formation raises the question of how large-scale estuarine morphology and the late Holocene

  17. Possible future effects of large-scale algae cultivation for biofuels on coastal eutrophication in Europe

    NARCIS (Netherlands)

    Blaas, H.; Kroeze, C.

    2014-01-01

    Biodiesel is increasingly considered as an alternative for fossil diesel. Biodiesel can be produced from rapeseed, palm, sunflower, soybean and algae. In this study, the consequences of large-scale production of biodiesel from micro-algae for eutrophication in four large European seas are analysed.

  18. Unscheduled load flow effect due to large variation in the distributed generation in a subtransmission network

    Science.gov (United States)

    Islam, Mujahidul

    A sustainable energy delivery infrastructure implies the safe and reliable accommodation of large scale penetration of renewable sources in the power grid. In this dissertation it is assumed there will be no significant change in the power transmission and distribution structure currently in place; except in the operating strategy and regulatory policy. That is to say, with the same old structure, the path towards unveiling a high penetration of switching power converters in the power system will be challenging. Some of the dimensions of this challenge are power quality degradation, frequent false trips due to power system imbalance, and losses due to a large neutral current. The ultimate result is the reduced life of many power distribution components - transformers, switches and sophisticated loads. Numerous ancillary services are being developed and offered by the utility operators to mitigate these problems. These services will likely raise the system's operational cost, not only from the utility operators' end, but also reflected on the Independent System Operators and by the Regional Transmission Operators (RTO) due to an unforeseen backlash of frequent variation in the load-side generation or distributed generation. The North American transmission grid is an interconnected system similar to a large electrical circuit. This circuit was not planned but designed over 100 years. The natural laws of physics govern the power flow among loads and generators except where control mechanisms are installed. The control mechanism has not matured enough to withstand the high penetration of variable generators at uncontrolled distribution ends. Unlike a radial distribution system, mesh or loop networks can alleviate complex channels for real and reactive power flow. Significant variation in real power injection and absorption on the distribution side can emerge as a bias signal on the routing reactive power in some physical links or channels that are not distinguishable

  19. Surprising transformation of a block copolymer into a high performance polystyrene ultrafiltration membrane with a hierarchically organized pore structure

    KAUST Repository

    Shevate, Rahul

    2018-02-08

    We describe the preparation of hierarchical polystyrene nanoporous membranes with a very narrow pore size distribution and an extremely high porosity. The nanoporous structure is formed as a result of unusual degradation of the poly(4-vinyl pyridine) block from self-assembled poly(styrene)-b-poly(4-vinyl pyridine) (PS-b-P4VP) membranes through the formation of an unstable pyridinium intermediate in an alkaline medium. During this process, the confined swelling and controlled degradation produced a tunable pore size. We unequivocally confirmed the successful elimination of the P4VP block from a PS-b-P4VPVP membrane using 1D/2D NMR spectroscopy and other characterization techniques. Surprisingly, the long range ordered surface porosity was preserved even after degradation of the P4VP block from the main chain of the diblock copolymer, as revealed by SEM. Aside from a drastically improved water flux (∼67% increase) compared to the PS-b-P4VP membrane, the hydraulic permeability measurements validated pH independent behaviour of the isoporous PS membrane over a wide pH range from 3 to 10. The effect of the pore size on protein transport rate and selectivity (a) was investigated for lysozyme (Lys), bovine serum albumin (BSA) and globulin-γ (IgG). A high selectivity of 42 (Lys/IgG) and 30 (BSA/IgG) was attained, making the membranes attractive for size selective separation of biomolecules from their synthetic model mixture solutions.

  20. How to reach clients of female sex workers: a survey by surprise in brothels in Dakar, Senegal.

    Science.gov (United States)

    Espirito Santo, M. E. Gomes do; Etheredge, G. D.

    2002-01-01

    OBJECTIVE: To describe the sampling techniques and survey procedures used in identifying male clients who frequent brothels to buy sexual services from female sex workers in Dakar, Senegal, with the aim of measuring the prevalence of human immunodeficiency virus (HIV) infection and investigating related risk behaviours. METHODS: Surveys were conducted in seven brothels in Dakar, Senegal. Clients were identified "by surprise" and interviewed and requested to donate saliva for HIV testing. RESULTS: Of the 1450 clients of prostitutes who were solicited to enter the study, 1140 (79.8%) agreed to be interviewed; 1083 (95%) of these clients provided saliva samples for testing. Of the samples tested, 47 were positive for HIV-1 or HIV-2, giving an HIV prevalence of 4.4%. CONCLUSION: The procedures adopted were successful in reaching the target population. Men present in the brothels could not deny being there, and it proved possible to explain the purpose of the study and to gain their confidence. Collection of saliva samples was shown to be an excellent method for performing HIV testing in difficult field conditions where it is hard to gain access to the population under study. The surveying of prostitution sites is recommended as a means of identifying core groups for HIV infection with a view to targeting education programmes more effectively. In countries such as Senegal, where the prevalence of HIV infection is still low, interventions among commercial sex workers and their clients may substantially delay the onset of a larger epidemic in the general population. PMID:12378288

  1. A computational study of ethylene–air sooting flames: Effects of large polycyclic aromatic hydrocarbons

    KAUST Repository

    Selvaraj, Prabhu

    2015-11-05

    An updated reduced gas-phase kinetic mechanism was developed and integrated with aerosol models to predict soot formation characteristics in ethylene nonpremixed and premixed flames. A primary objective is to investigate the sensitivity of the soot formation to various chemical pathways for large polycyclic aromatic hydrocarbons (PAH). The gas-phase chemical mechanism adopted the KAUST-Aramco PAH Mech 1.0, which utilized the AramcoMech 1.3 for gas-phase reactions validated for up to C2 fuels. In addition, PAH species up to coronene (C24H12 or A7) were included to describe the detailed formation pathways of soot precursors. In this study, the detailed chemical mechanism was reduced from 397 to 99 species using directed relation graph with expert knowledge (DRG-X) and sensitivity analysis. The method of moments with interpolative closure (MOMIC) was employed for the soot aerosol model. Counterflow nonpremixed flames at low strain rate sooting conditions were considered, for which the sensitivity of soot formation characteristics to different nucleation pathways were investigated. Premixed flame experiment data at different equivalence ratios were also used for validation. The findings show that higher PAH concentrations result in a higher soot nucleation rate, and that the total soot volume and average size of the particles are predicted in good agreement with experimental results. Subsequently, the effects of different pathways, with respect to pyrene- or coronene-based nucleation models, on the net soot formation rate were analyzed. It was found that the nucleation processes (i.e., soot inception) are sensitive to the choice of PAH precursors, and consideration of higher PAH species beyond pyrene is critical for accurate prediction of the overall soot formation.

  2. Effect of grid resolution on large eddy simulation of wall-bounded turbulence

    Science.gov (United States)

    Rezaeiravesh, S.; Liefvendahl, M.

    2018-05-01

    The effect of grid resolution on a large eddy simulation (LES) of a wall-bounded turbulent flow is investigated. A channel flow simulation campaign involving a systematic variation of the streamwise (Δx) and spanwise (Δz) grid resolution is used for this purpose. The main friction-velocity-based Reynolds number investigated is 300. Near the walls, the grid cell size is determined by the frictional scaling, Δx+ and Δz+, and strongly anisotropic cells, with first Δy+ ˜ 1, thus aiming for the wall-resolving LES. Results are compared to direct numerical simulations, and several quality measures are investigated, including the error in the predicted mean friction velocity and the error in cross-channel profiles of flow statistics. To reduce the total number of channel flow simulations, techniques from the framework of uncertainty quantification are employed. In particular, a generalized polynomial chaos expansion (gPCE) is used to create metamodels for the errors over the allowed parameter ranges. The differing behavior of the different quality measures is demonstrated and analyzed. It is shown that friction velocity and profiles of the velocity and Reynolds stress tensor are most sensitive to Δz+, while the error in the turbulent kinetic energy is mostly influenced by Δx+. Recommendations for grid resolution requirements are given, together with the quantification of the resulting predictive accuracy. The sensitivity of the results to the subgrid-scale (SGS) model and varying Reynolds number is also investigated. All simulations are carried out with second-order accurate finite-volume-based solver OpenFOAM. It is shown that the choice of numerical scheme for the convective term significantly influences the error portraits. It is emphasized that the proposed methodology, involving the gPCE, can be applied to other modeling approaches, i.e., other numerical methods and the choice of SGS model.

  3. The Composite Regulatory Basis of the Large X-Effect in Mouse Speciation.

    Science.gov (United States)

    Larson, Erica L; Keeble, Sara; Vanderpool, Dan; Dean, Matthew D; Good, Jeffrey M

    2017-02-01

    The disruption of meiotic sex chromosome inactivation (MSCI) has been proposed to be a major developmental mechanism underlying the rapid evolution of hybrid male sterility. We tested this idea by analyzing cell-specific gene expression across spermatogenesis in two lineages of house mice and their sterile and fertile reciprocal hybrids. We found pervasive disruption of sex chromosome gene expression in sterile hybrids at every stage of spermatogenesis. Failure of MSCI was developmentally preceded by increased silencing of autosomal genes, supporting the hypothesis that divergence at the hybrid incompatibility gene, Prdm9, results in increased rates of autosomal asynapsis which in turn triggers widespread silencing of unsynapsed chromatin. We also detected opposite patterns of postmeiotic overexpression or hyper-repression of the sex chromosomes in reciprocal hybrids, supporting the hypothesis that genomic conflict has driven functional divergence that leads to deleterious X-Y dosage imbalances in hybrids. Our developmental timeline also exposed more subtle patterns of mitotic misregulation on the X chromosome, a previously undocumented stage of spermatogenic disruption in this cross. These results indicate that multiple hybrid incompatibilities have converged on a common regulatory phenotype, the disrupted expression of the sex chromosomes during spermatogenesis. Collectively, these data reveal a composite regulatory basis to hybrid male sterility in mice that helps resolve the mechanistic underpinnings of the well-documented large X-effect in mice speciation. We propose that the inherent sensitivity of spermatogenesis to X-linked regulatory disruption has the potential to be a major driver of reproductive isolation in species with chromosomal sex determination. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Effect of classic back massage on spinal pain in a woman with large breasts - case report

    Directory of Open Access Journals (Sweden)

    Natalia Zielińska

    2017-07-01

    Full Text Available Introduction. The most common ailment of the motion system is spinal pain. For one of the main reasons, it consider a sedentary lifestyle that weakens the musculo-skeletal system, obesity that increases spine load, sleep disorders resulting from unsettled positions during rest or sleep, and chronic stress. The use of massage can reduce the painful pain of the spine, by loosening the excessively tight spine muscles, the articular joints of the joints and the relaxation of the body. Objective. An assessment of the effect of classical spine massage on spinal pain in a woman with large breasts. Material and methods. 10 massage treatments of the classical ridge using olive oil were performed. Sessions took place 2-3 times a week after 30-50 minutes. Before and after intervention were measured: linear measurements of upper and lower limbs; Measurement of the first and short long and short for the upper and lower limbs for the upper and lower extremities; Measurement of the range of mobility of individual segments of the spine; Measurement of muscle strength of the cervical, thoracic and lumbar musculature of the upper limbs; Assessment of deviation from the symmetry of body posture. Also tested was the Cross Stroke Challenge, finger-to-floor test, lumbar vertebrae overtaxis test, Laseque test, Scherer test and Gilett test. Results. The difference in the range of motion, ie the flexion of the thorax and lumbar spine and the finger-to-floor examination, was statistically significantly different. After intervention the silhouette of the body was positioned closer to the vertical axis. The Laseque test for both lower limbs turned out to be negative. The difference in linear and limb length measurements and the Schober test was not statistically significant. The test of cross-provocation, the overtaking test for the lumbar spine movement and the Gillet test did not show deviations before or after intervention. Conclusions. Therapeutic massage of the

  5. An effective fractal-tree closure model for simulating blood flow in large arterial networks.

    Science.gov (United States)

    Perdikaris, Paris; Grinberg, Leopold; Karniadakis, George Em

    2015-06-01

    The aim of the present work is to address the closure problem for hemodynamic simulations by developing a flexible and effective model that accurately distributes flow in the downstream vasculature and can stably provide a physiological pressure outflow boundary condition. To achieve this goal, we model blood flow in the sub-pixel vasculature by using a non-linear 1D model in self-similar networks of compliant arteries that mimic the structure and hierarchy of vessels in the meso-vascular regime (radii [Formula: see text]). We introduce a variable vessel length-to-radius ratio for small arteries and arterioles, while also addressing non-Newtonian blood rheology and arterial wall viscoelasticity effects in small arteries and arterioles. This methodology aims to overcome substantial cut-off radius sensitivities, typically arising in structured tree and linearized impedance models. The proposed model is not sensitive to outflow boundary conditions applied at the end points of the fractal network, and thus does not require calibration of resistance/capacitance parameters typically required for outflow conditions. The proposed model convergences to a periodic state in two cardiac cycles even when started from zero-flow initial conditions. The resulting fractal-trees typically consist of thousands to millions of arteries, posing the need for efficient parallel algorithms. To this end, we have scaled up a Discontinuous Galerkin solver that utilizes the MPI/OpenMP hybrid programming paradigm to thousands of computer cores, and can simulate blood flow in networks of millions of arterial segments at the rate of one cycle per 5 min. The proposed model has been extensively tested on a large and complex cranial network with 50 parent, patient-specific arteries and 21 outlets to which fractal trees where attached, resulting to a network of up to 4,392,484 vessels in total, and a detailed network of the arm with 276 parent arteries and 103 outlets (a total of 702,188 vessels

  6. Cerebral metastasis masquerading as cerebritis: A case of misguiding history and radiological surprise!

    Directory of Open Access Journals (Sweden)

    Ashish Kumar

    2013-01-01

    Full Text Available Cerebral metastases usually have a characteristic radiological appearance. They can be differentiated rather easily from any infective etiology. Similarly, positive medical history also guides the neurosurgeon towards the possible diagnosis and adds to the diagnostic armamentarium. However, occasionally, similarities on imaging may be encountered where even history could lead us in the wrong direction and tends to bias the clinician. We report a case of a 40-year-old female with a history of mastoidectomy for otitis media presenting to us with a space occupying lesion in the right parietal region, which was thought pre-operatively as an abscess along with the cerebritis. Surprisingly, the histopathology proved it to be a metastatic adenocarcinoma. Hence, a ring enhancing lesion may be a high grade neoplasm/metastasis/abscess, significant gyral enhancement; a feature of cerebritis is not linked with a neoplastic etiology more often. This may lead to delayed diagnosis, incorrect prognostication and treatment in patients having coincidental suggestive history of infection. We review the literature and highlight the key points helping to differentiate an infective from a neoplastic pathology which may look similar at times.

  7. Beyond interests and institutions: US health policy reform and the surprising silence of big business.

    Science.gov (United States)

    Smyrl, Marc E

    2014-02-01

    Interest-based arguments do not provide satisfying explanations for the surprising reticence of major US employers to take a more active role in the debate surrounding the 2010 Patient Protection and Affordable Care Act (ACA). Through focused comparison with the Bismarckian systems of France and Germany, on the one hand, and with the 1950s and 1960s in the United States, on the other, this article concludes that while institutional elements do account for some of the observed behavior of big business, a necessary complement to this is a fuller understanding of the historically determined legitimating ideology of US firms. From the era of the "corporate commonwealth," US business inherited the principles of private welfare provision and of resistance to any expansion of government control. Once complementary, these principles are now mutually exclusive: employer-provided health insurance increasingly is possible only at the cost of ever-increasing government subsidy and regulation. Paralyzed by the uncertainty that followed from this clash of legitimate ideas, major employers found themselves unable to take a coherent and unified stand for or against the law. As a consequence, they failed either to oppose it successfully or to secure modifications to it that would have been useful to them.

  8. From Lithium-Ion to Sodium-Ion Batteries: Advantages, Challenges, and Surprises.

    Science.gov (United States)

    Nayak, Prasant Kumar; Yang, Liangtao; Brehm, Wolfgang; Adelhelm, Philipp

    2018-01-02

    Mobile and stationary energy storage by rechargeable batteries is a topic of broad societal and economical relevance. Lithium-ion battery (LIB) technology is at the forefront of the development, but a massively growing market will likely put severe pressure on resources and supply chains. Recently, sodium-ion batteries (SIBs) have been reconsidered with the aim of providing a lower-cost alternative that is less susceptible to resource and supply risks. On paper, the replacement of lithium by sodium in a battery seems straightforward at first, but unpredictable surprises are often found in practice. What happens when replacing lithium by sodium in electrode reactions? This review provides a state-of-the art overview on the redox behavior of materials when used as electrodes in lithium-ion and sodium-ion batteries, respectively. Advantages and challenges related to the use of sodium instead of lithium are discussed. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Surprises from the resolution of operator mixing in N=4 SYM

    International Nuclear Information System (INIS)

    Bianchi, Massimo; Rossi, Giancarlo; Stanev, Yassen S.

    2004-01-01

    We reexamine the problem of operator mixing in N=4 SYM. Particular attention is paid to the correct definition of composite gauge invariant local operators, which is necessary for the computation of their anomalous dimensions beyond lowest order. As an application we reconsider the case of operators with naive dimension Δ 0 =4, already studied in the literature. Stringent constraints from the resummation of logarithms in power behaviours are exploited and the role of the generalized N=4 Konishi anomaly in the mixing with operators involving fermions is discussed. A general method for the explicit (numerical) resolution of the operator mixing and the computation of anomalous dimensions is proposed. We then resolve the order g 2 mixing for the 15 (purely scalar) singlet operators of naive dimension Δ 0 =6. Rather surprisingly we find one isolated operator which has a vanishing anomalous dimension up to order g 4 , belonging to an apparently long multiplet. We also solve the order g 2 mixing for the 26 operators belonging to the representation 20' of SU(4). We find an operator with the same one-loop anomalous dimension as the Konishi multiplet

  10. Large-scale assessment of flood risk and the effects of mitigation measures along the Elbe River

    NARCIS (Netherlands)

    de Kok, Jean-Luc; Grossmann, M.

    2010-01-01

    The downstream effects of flood risk mitigation measures and the necessity to develop flood risk management strategies that are effective on a basin scale call for a flood risk assessment methodology that can be applied at the scale of a large river. We present an example of a rapid flood risk

  11. Tube-dwelling invertebrates: tiny ecosystem engineers have large effects in lake ecosystems

    NARCIS (Netherlands)

    Hölker, Franz; Vanni, Michael J.; Kuiper, Jan J.; Meile, Christof; Grossart, Hans-Peter; Stief, Peter; Adrian, Rita; Lorke, Andreas; Dellwig, Olaf; Brand, Andreas; Hupfer, Michael; Mooij, Wolf M.; Nützmann, Gunnar; Lewandowski, Jörg

    2015-01-01

    There is ample evidence that tube-dwelling invertebrates such as chironomids significantly alter multiple important ecosystem functions, particularly in shallow lakes. Chironomids pump large water volumes, and associated suspended and dissolved substances, through the sediment and thereby compete

  12. Surface States Effect on the Large Photoluminescence Redshift in GaN Nanostructures

    KAUST Repository

    Ben Slimane, Ahmed; Najar, Adel; Ooi, Boon S.; Shen, Chao; Anjum, Dalaver H.; San-Romá n-Alerigi, Damiá n P.; Ng, Tien Khee

    2013-01-01

    We report on the large photoluminescence redshift observed in nanostructures fabricated using n-type GaN by ultraviolet (UV) metal-assisted electroless chemical-etching method. The scanning electron microscopy (SEM) characterization showed

  13. Side effects of problem-solving strategies in large-scale nutrition science: towards a diversification of health.

    Science.gov (United States)

    Penders, Bart; Vos, Rein; Horstman, Klasien

    2009-11-01

    Solving complex problems in large-scale research programmes requires cooperation and division of labour. Simultaneously, large-scale problem solving also gives rise to unintended side effects. Based upon 5 years of researching two large-scale nutrigenomic research programmes, we argue that problems are fragmented in order to be solved. These sub-problems are given priority for practical reasons and in the process of solving them, various changes are introduced in each sub-problem. Combined with additional diversity as a result of interdisciplinarity, this makes reassembling the original and overall goal of the research programme less likely. In the case of nutrigenomics and health, this produces a diversification of health. As a result, the public health goal of contemporary nutrition science is not reached in the large-scale research programmes we studied. Large-scale research programmes are very successful in producing scientific publications and new knowledge; however, in reaching their political goals they often are less successful.

  14. Large reversible magnetostrictive effect of MnCoSi-based compounds prepared by high-magnetic-field solidification

    Science.gov (United States)

    Hu, Q. B.; Hu, Y.; Zhang, S.; Tang, W.; He, X. J.; Li, Z.; Cao, Q. Q.; Wang, D. H.; Du, Y. W.

    2018-01-01

    The MnCoSi compound is a potential magnetostriction material since the magnetic field can drive a metamagnetic transition from an antiferromagnetic phase to a high magnetization phase in it, which accompanies a large lattice distortion. However, a large driving magnetic field, magnetic hysteresis, and poor mechanical properties seriously hinder its application for magnetostriction. By substituting Fe for Mn and introducing vacancies of the Mn element, textured and dense Mn0.97Fe0.03CoSi and Mn0.88CoSi compounds are prepared through a high-magnetic-field solidification approach. As a result, large room-temperature and reversible magnetostriction effects are observed in these compounds at a low magnetic field. The origin of this large magnetostriction effect and potential applications are discussed.

  15. Herbivore grazing?or trampling? Trampling effects by a large ungulate in cold high?latitude ecosystems

    OpenAIRE

    Heggenes, Jan; Odland, Arvid; Chevalier, Tomas; Ahlberg, J?rgen; Berg, Amanda; Larsson, H?kan; Bjerketvedt, Dag K.

    2017-01-01

    Mammalian herbivores have important top-down effects on ecological processes and landscapes by generating vegetation changes through grazing and trampling. For free-ranging herbivores on large landscapes, trampling is an important ecological factor. However, whereas grazing is widely studied, low-intensity trampling is rarely studied and quantified. The cold-adapted northern tundra reindeer (Rangifer tarandus) is a wide-ranging keystone herbivore in large open alpine and Arctic ecosystems. Re...

  16. Mitigating Aviation Communication and Satellite Orbit Operations Surprises from Adverse Space Weather

    Science.gov (United States)

    Tobiska, W. Kent

    2008-01-01

    Adverse space weather affects operational activities in aviation and satellite systems. For example, large solar flares create highly variable enhanced neutral atmosphere and ionosphere electron density regions. These regions impact aviation communication frequencies as well as precision orbit determination. The natural space environment, with its dynamic space weather variability, is additionally changed by human activity. The increase in orbital debris in low Earth orbit (LEO), combined with lower atmosphere CO2 that rises into the lower thermosphere and causes increased cooling that results in increased debris lifetime, adds to the environmental hazards of navigating in near-Earth space. This is at a time when commercial space endeavors are posed to begin more missions to LEO during the rise of the solar activity cycle toward the next maximum (2012). For satellite and aviation operators, adverse space weather results in greater expenses for orbit management, more communication outages or aviation and ground-based high frequency radio used, and an inability to effectively plan missions or service customers with space-based communication, imagery, and data transferal during time-critical activities. Examples of some revenue-impacting conditions and solutions for mitigating adverse space weather are offered.

  17. Short- and Medium-term Atmospheric Effects of Very Large Solar Proton Events

    Science.gov (United States)

    Jackman, Charles H.; Marsh, Daniel R.; Vitt, Francis M.; Garcia, Rolando R.; Fleming, Eric L.; Labow, Gordon J.; Randall, Cora E.; Lopez-Puertas, Manuel; Funke, Bernd

    2007-01-01

    Long-term variations in ozone have been caused by both natural and humankind related processes. In particular, the humankind or anthropogenic influence on ozone from chlorofluorocarbons and halons (chlorine and bromine) has led to international regulations greatly limiting the release of these substances. These anthropogenic effects on ozone are most important in polar regions and have been significant since the 1970s. Certain natural ozone influences are also important in polar regions and are caused by the impact of solar charged particles on the atmosphere. Such natural variations have been studied in order to better quantify the human influence on polar ozone. Large-scale explosions on the Sun near solar maximum lead to emissions of charged particles (mainly protons and electrons), some of which enter the Earth's magnetosphere and rain down on the polar regions. "Solar proton events" have been used to describe these phenomena since the protons associated with these solar events sometimes create a significant atmospheric disturbance. We have used the National Center for Atmospheric Research (NCAR) Whole Atmosphere Community Climate Model (WACCM) to study the short- and medium-term (days to a few months) influences of solar proton events between 1963 and 2005 on stratospheric ozone. The four largest events in the past 45 years (August 1972; October 1989; July 2000; and October-November 2003) caused very distinctive polar changes in layers of the Earth's atmosphere known as the stratosphere (12-50 km; -7-30 miles) and mesosphere (50-90 km; 30-55 miles). The solar protons connected with these events created hydrogen- and nitrogen- containing compounds, which led to the polar ozone destruction. The hydrogen-containing compounds have very short lifetimes and lasted for only a few days (typically the duration of the solar proton event). On the other hand, the nitrogen-containing compounds lasted much longer, especially in the Winter. The nitrogen oxides were predicted

  18. Effect of GFRP spacer on local deformation of large superconductor in coil pack

    International Nuclear Information System (INIS)

    Nishimura, Arata; Tamura, Hitoshi; Mito, Toshiyuki; Yamamoto, Junya

    1994-01-01

    Design and construction of the Large Helical Device (LHD) are in progress at the National Institute for Fusion Science (NIFS) in Japan. The LHD has superconducting poloidal and helical coils, and many efforts have been undertaken to develop these large superconductors. When designing a large superconducting magnet, the mechanical behavior of the wound structure becomes a very important factor since the apparent rigidity affects the design of a coil support structure and the superconducting coil needs to endure the large electro-magnetic force it creates. Also, non-linear mechanical behavior should yield the instability of the magnet. In this paper, local deformation in a large conductor caused by GFRP spacers and epoxy adhesives was investigated after compressive rigidity testing. The epoxy adhesive used for attaching the GFRP spacers to the superconductor changed shape from an almost square sheet into a lens-like sheet during deformation, and a dent appeared on the surface of the superconductor. Three-dimensional FEM analysis showed that a compressive stress in the vertical direction of the loading axis existed in the adhesive plane. This stress component makes the adhesive lens-like and it results in the dent created during the compressive testing. This local deformation should yield a part of the permanent deformation observed after the compressive load cycle at 4.2 K

  19. A conceptual geochemical model of the geothermal system at Surprise Valley, CA

    Science.gov (United States)

    Fowler, Andrew P. G.; Ferguson, Colin; Cantwell, Carolyn A.; Zierenberg, Robert A.; McClain, James; Spycher, Nicolas; Dobson, Patrick

    2018-03-01

    Characterizing the geothermal system at Surprise Valley (SV), northeastern California, is important for determining the sustainability of the energy resource, and mitigating hazards associated with hydrothermal eruptions that last occurred in 1951. Previous geochemical studies of the area attempted to reconcile different hot spring compositions on the western and eastern sides of the valley using scenarios of dilution, equilibration at low temperatures, surface evaporation, and differences in rock type along flow paths. These models were primarily supported using classical geothermometry methods, and generally assumed that fluids in the Lake City mud volcano area on the western side of the valley best reflect the composition of a deep geothermal fluid. In this contribution, we address controls on hot spring compositions using a different suite of geochemical tools, including optimized multicomponent geochemistry (GeoT) models, hot spring fluid major and trace element measurements, mineralogical observations, and stable isotope measurements of hot spring fluids and precipitated carbonates. We synthesize the results into a conceptual geochemical model of the Surprise Valley geothermal system, and show that high-temperature (quartz, Na/K, Na/K/Ca) classical geothermometers fail to predict maximum subsurface temperatures because fluids re-equilibrated at progressively lower temperatures during outflow, including in the Lake City area. We propose a model where hot spring fluids originate as a mixture between a deep thermal brine and modern meteoric fluids, with a seasonally variable mixing ratio. The deep brine has deuterium values at least 3 to 4‰ lighter than any known groundwater or high-elevation snow previously measured in and adjacent to SV, suggesting it was recharged during the Pleistocene when meteoric fluids had lower deuterium values. The deuterium values and compositional characteristics of the deep brine have only been identified in thermal springs and

  20. Explanatory models of health and disease: surprises from within the former Soviet Union

    Directory of Open Access Journals (Sweden)

    Tatiana I Andreeva

    2013-06-01

    Full Text Available Extract The review of anthropological theories as applied to public health by Jennifer J. Carroll (Carroll, 2013 published in this issue of TCPHEE made me recollect my first and most surprising discoveries of how differently same things can be understood in different parts of the world. Probably less unexpectedly, these impressions concern substance abuse and addiction behaviors, similarly to many examples deployed by Jennifer J. Carroll. The first of these events happened soon after the break-up of the Soviet Union when some of the most active people from the West rushed to discover what was going on behind the opening iron curtain. A director of an addiction clinic, who had just come into contact with a Dutch counterpart, invited me to join the collaboration and the innovation process he planned to launch. Being a participant of the exchange program started within this collaboration, I had an opportunity to discover how addictive behaviors were understood and explained in books (English, 1961; Kooyman, 1992; Viorst, 1986 recommended by the colleagues in the Netherlands and, as I could observe with my own eyes, addressed in everyday practice. This was a jaw-dropping contrast to what I learnt at the soviet medical university and some post-graduate courses, where all the diseases related to alcohol, tobacco, or drug abuse were considered predominantly a result of the substance intake. In the Soviet discourse, the intake itself was understood as 'willful and deliberate' or immoral behavior which, in some cases, was to be rectified in prison-like treatment facilities. In the West, quite oppositely, substance abuse was seen rather as a consequence of a constellation of life-course adversities thoroughly considered by developmental psychology. This approach was obviously deeply ingrained in how practitioners diagnosed and treated their patients.

  1. Metaproteomics of cellulose methanisation under thermophilic conditions reveals a surprisingly high proteolytic activity.

    Science.gov (United States)

    Lü, Fan; Bize, Ariane; Guillot, Alain; Monnet, Véronique; Madigou, Céline; Chapleur, Olivier; Mazéas, Laurent; He, Pinjing; Bouchez, Théodore

    2014-01-01

    Cellulose is the most abundant biopolymer on Earth. Optimising energy recovery from this renewable but recalcitrant material is a key issue. The metaproteome expressed by thermophilic communities during cellulose anaerobic digestion was investigated in microcosms. By multiplying the analytical replicates (65 protein fractions analysed by MS/MS) and relying solely on public protein databases, more than 500 non-redundant protein functions were identified. The taxonomic community structure as inferred from the metaproteomic data set was in good overall agreement with 16S rRNA gene tag pyrosequencing and fluorescent in situ hybridisation analyses. Numerous functions related to cellulose and hemicellulose hydrolysis and fermentation catalysed by bacteria related to Caldicellulosiruptor spp. and Clostridium thermocellum were retrieved, indicating their key role in the cellulose-degradation process and also suggesting their complementary action. Despite the abundance of acetate as a major fermentation product, key methanogenesis enzymes from the acetoclastic pathway were not detected. In contrast, enzymes from the hydrogenotrophic pathway affiliated to Methanothermobacter were almost exclusively identified for methanogenesis, suggesting a syntrophic acetate oxidation process coupled to hydrogenotrophic methanogenesis. Isotopic analyses confirmed the high dominance of the hydrogenotrophic methanogenesis. Very surprising was the identification of an abundant proteolytic activity from Coprothermobacter proteolyticus strains, probably acting as scavenger and/or predator performing proteolysis and fermentation. Metaproteomics thus appeared as an efficient tool to unravel and characterise metabolic networks as well as ecological interactions during methanisation bioprocesses. More generally, metaproteomics provides direct functional insights at a limited cost, and its attractiveness should increase in the future as sequence databases are growing exponentially.

  2. [Fall from height--surprising autopsy diagnosis in primarily unclear initial situations].

    Science.gov (United States)

    Schyma, Christian; Doberentz, Elke; Madea, Burkhard

    2012-01-01

    External post-mortem examination and first police assessments are often not consistent with subsequent autopsy results. This is all the more surprising the more serious the injuries found at autopsy are. Such discrepancies result especially from an absence of gross external injuries, as demonstrated by four examples. A 42-year-old, externally uninjured male was found at night time in a helpless condition in the street and died in spite of resuscitation. Autopsy showed severe polytrauma with traumatic brain injury and lesions of the thoracic and abdominal organs. A jump from the third floor was identified as the cause. At dawn, a twenty-year-old male was found dead on the grounds of the adjacent house. Because of the blood-covered head the police assumed a traumatic head injury by strike impact. The external examination revealed only abrasions on the forehead and to a minor extent on the back. At autopsy a midfacial fracture, a trauma of the thorax and abdomen and fractures of the spine and pelvis were detected. Afterwards investigations showed that the man, intoxicated by alcohol, had fallen from the flat roof of a multistoried house. A 77-year-old man was found unconscious on his terrace at day time; a cerebral seizure was assumed. He was transferred to emergency care where he died. The corpse was externally inconspicuous. Autopsy revealed serious traumatic injuries of the brain, thorax, abdomen and pelvis, which could be explained by a fall from the balcony. A 47-year-old homeless person without any external injuries was found dead in a barn. An alcohol intoxication was assumed. At autopsy severe injuries of the brain and cervical spine were found which were the result of a fall from a height of 5 m. On the basis of an external post-mortem examination alone gross blunt force trauma cannot be reliably excluded.

  3. Technological monitoring radar: a weak signals interpretation tool for the identification of strategic surprises

    Directory of Open Access Journals (Sweden)

    Adalton Ozaki

    2011-07-01

    Full Text Available In the current competitive scenario, marked by rapid and constant changes, it is vital that companies actively monitor the business environment, in search of signs which might anticipate changes. This study poses to propose and discuss a tool called Technological Monitoring Radar, which endeavours to address the following query: “How can a company systematically monitor the environment and capture signs that anticipate opportunities and threats concerning a particular technology?”. The literature review covers Competitive Intelligence, Technological Intelligence, Environmental Analysis and Anticipative Monitoring. Based on the critical analysis of the literature, a tool called Technological Monitoring Radar is proposed comprising five environments to be monitored (political, economical, technological, social and competition each of which with key topics for analysis. To exemplify the use of the tool, it is applied to the smartphone segment in an exclusively reflexive manner, and without the participation of a specific company. One of the suggestions for future research is precisely the application of the proposed methodology in an actual company. Despite the limitation of this being a theoretical study, the example demonstrated the tool´s applicability. The radar prove to be very useful for a company that needs to monitor the environment in search of signs of change. This study´s main contribution is to relate different fields of study (technological intelligence, environmental analysis and anticipative monitoring and different approaches to provide a practical tool that allows a manager to identify and better visualize opportunities and threats, thus avoiding strategic surprises in the technological arena.Key words: Technological monitoring. Technological intelligence. Competitive intelligence. Weak signals.

  4. The genome of Pelobacter carbinolicus reveals surprising metabolic capabilities and physiological features

    Energy Technology Data Exchange (ETDEWEB)

    Aklujkar, Muktak [University of Massachusetts, Amherst; Haveman, Shelley [University of Massachusetts, Amherst; DiDonatoJr, Raymond [University of Massachusetts, Amherst; Chertkov, Olga [Los Alamos National Laboratory (LANL); Han, Cliff [Los Alamos National Laboratory (LANL); Land, Miriam L [ORNL; Brown, Peter [University of Massachusetts, Amherst; Lovley, Derek [University of Massachusetts, Amherst

    2012-01-01

    Background: The bacterium Pelobacter carbinolicus is able to grow by fermentation, syntrophic hydrogen/formate transfer, or electron transfer to sulfur from short-chain alcohols, hydrogen or formate; it does not oxidize acetate and is not known to ferment any sugars or grow autotrophically. The genome of P. carbinolicus was sequenced in order to understand its metabolic capabilities and physiological features in comparison with its relatives, acetate-oxidizing Geobacter species. Results: Pathways were predicted for catabolism of known substrates: 2,3-butanediol, acetoin, glycerol, 1,2-ethanediol, ethanolamine, choline and ethanol. Multiple isozymes of 2,3-butanediol dehydrogenase, ATP synthase and [FeFe]-hydrogenase were differentiated and assigned roles according to their structural properties and genomic contexts. The absence of asparagine synthetase and the presence of a mutant tRNA for asparagine encoded among RNA-active enzymes suggest that P. carbinolicus may make asparaginyl-tRNA in a novel way. Catabolic glutamate dehydrogenases were discovered, implying that the tricarboxylic acid (TCA) cycle can function catabolically. A phosphotransferase system for uptake of sugars was discovered, along with enzymes that function in 2,3-butanediol production. Pyruvate: ferredoxin/flavodoxin oxidoreductase was identified as a potential bottleneck in both the supply of oxaloacetate for oxidation of acetate by the TCA cycle and the connection of glycolysis to production of ethanol. The P. carbinolicus genome was found to encode autotransporters and various appendages, including three proteins with similarity to the geopilin of electroconductive nanowires. Conclusions: Several surprising metabolic capabilities and physiological features were predicted from the genome of P. carbinolicus, suggesting that it is more versatile than anticipated.

  5. A post-genomic surprise. The molecular reinscription of race in science, law and medicine.

    Science.gov (United States)

    Duster, Troy

    2015-03-01

    The completion of the first draft of the Human Genome Map in 2000 was widely heralded as the promise and future of genetics-based medicines and therapies - so much so that pundits began referring to the new century as 'The Century of Genetics'. Moreover, definitive assertions about the overwhelming similarities of all humans' DNA (99.9 per cent) by the leaders of the Human Genome Project were trumpeted as the end of racial thinking about racial taxonomies of human genetic differences. But the first decade of the new century brought unwelcomed surprises. First, gene therapies turned out to be far more complicated than any had anticipated - and instead the pharmaceutical industry turned to a focus on drugs that might be 'related' to population differences based upon genetic markers. While the language of 'personalized medicine' dominated this frame, research on racially and ethnically designated populations differential responsiveness to drugs dominated the empirical work in the field. Ancestry testing and 'admixture research' would play an important role in a new kind of molecular reification of racial categories. Moreover, the capacity of the super-computer to map differences reverberated into personal identification that would affect both the criminal justice system and forensic science, and generate new levels of concern about personal privacy. Social scientists in general, and sociologists in particular, have been caught short by these developments - relying mainly on assertions that racial categories are socially constructed, regionally and historically contingent, and politically arbitrary. While these assertions are true, the imprimatur of scientific legitimacy has shifted the burden, since now 'admixture research' can claim that its results get at the 'reality' of human differentiation, not the admittedly flawed social constructions of racial categories. Yet what was missing from this framing of the problem: 'admixture research' is itself based upon socially

  6. The Large-Scale Biosphere-Atmosphere Experiment in Amazonia: Analyzing Regional Land Use Change Effects.

    Science.gov (United States)

    Michael Keller; Maria Assunção Silva-Dias; Daniel C. Nepstad; Meinrat O. Andreae

    2004-01-01

    The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multi-disciplinary, multinational scientific project led by Brazil. LBA researchers seek to understand Amazonia in its global context especially with regard to regional and global climate. Current development activities in Amazonia including deforestation, logging, cattle ranching, and agriculture...

  7. Verbalizing, Visualizing, and Navigating: The Effect of Strategies on Encoding a Large-Scale Virtual Environment

    Science.gov (United States)

    Kraemer, David J. M.; Schinazi, Victor R.; Cawkwell, Philip B.; Tekriwal, Anand; Epstein, Russell A.; Thompson-Schill, Sharon L.

    2017-01-01

    Using novel virtual cities, we investigated the influence of verbal and visual strategies on the encoding of navigation-relevant information in a large-scale virtual environment. In 2 experiments, participants watched videos of routes through 4 virtual cities and were subsequently tested on their memory for observed landmarks and their ability to…

  8. EFFECTIVENESS OF LARGE WOODY DEBRIS IN STREAM REHABILITATION PROJECTS IN URBAN BASINS. (R825284)

    Science.gov (United States)

    Urban stream rehabilitation projects commonly include log placement to establish the types of habitat features associated with large woody debris (LWD) in undisturbed streams. Six urban in-stream rehabilitation projects were examined in the Puget Sound Lowland of western Washi...

  9. Predicting the effect of fire on large-scale vegetation patterns in North America.

    Science.gov (United States)

    Donald McKenzie; David L. Peterson; Ernesto. Alvarado

    1996-01-01

    Changes in fire regimes are expected across North America in response to anticipated global climatic changes. Potential changes in large-scale vegetation patterns are predicted as a result of altered fire frequencies. A new vegetation classification was developed by condensing Kuchler potential natural vegetation types into aggregated types that are relatively...

  10. History, physical effects, and management implications of large organic debris in western Oregon streams.

    Science.gov (United States)

    Frederick Swanson; George W. Lienkaemper; James R. Sedell

    1976-01-01

    Large organic debris has historically been an important element in small mountain streams of the Pacific Northwest. The debris serves to slow the movement of water and inorganic and fine organic matter through the channel. Debris may remain in the channel for decades or longer, and tends to stabilize some sections of a streambed and stream banks while destabilizing...

  11. A computational study of ethylene–air sooting flames: Effects of large polycyclic aromatic hydrocarbons

    KAUST Repository

    Selvaraj, Prabhu; Arias, Paul G.; Lee, Bok Jik; Im, Hong G.; Wang, Yu; Gao, Yang; Park, Sungwoo; Sarathy, Mani; Lu, Tianfeng; Chung, Suk-Ho

    2015-01-01

    formation to various chemical pathways for large polycyclic aromatic hydrocarbons (PAH). The gas-phase chemical mechanism adopted the KAUST-Aramco PAH Mech 1.0, which utilized the AramcoMech 1.3 for gas-phase reactions validated for up to C2 fuels

  12. Effects of large herbivores on wood pasture dynamics in a European wetland system

    NARCIS (Netherlands)

    Cornelissen, P.; Bokdam, J.; Sykora, K.V.; Berendse, F.

    2014-01-01

    Whether self-regulating large herbivores play a key role in the development of wood-pasture landscapes remains a crucial unanswered question for both ecological theory and nature conservation. We describe and analyse how a ‘partly self-regulating’ population of cattle, horses and red deer affected

  13. Distributed measurement system for long term monitoring of clouding effects on large PV plants

    DEFF Research Database (Denmark)

    Paasch, K. M.; Nymand, M.; Haase, F.

    2013-01-01

    A recording system for the generation of current-voltage characteristics of solar panels is presented. The system is intended for large area PV power plants. The recorded curves are used to optimize the energy output of PV power plants, which are likely to be influenced by passing clouds...

  14. Some effects of integrated production planning in large-scale kitchens

    DEFF Research Database (Denmark)

    Engelund, Eva Høy; Friis, Alan; Jacobsen, Peter

    2005-01-01

    Integrated production planning in large-scale kitchens proves advantageous for increasing the overall quality of the food produced and the flexibility in terms of a diverse food supply. The aim is to increase the flexibility and the variability in the production as well as the focus on freshness ...

  15. External human factors in incident management team decisionmaking and their effect on large fire suppression expenditures

    Science.gov (United States)

    Janie Canton-Tompson; Krista M. Gebert; Brooke Thompson; Greg Jones; David Calkin; Geoff. Donovan

    2008-01-01

    Large wildland fires are complex, costly events influenced by a vast array of physical, climatic, and social factors. Changing climate, fuel buildup due to past suppression, and increasing populations in the wildland-urban interface have all been blamed for the extreme fire seasons and rising suppression expenditures of recent years. With each high-cost year comes a...

  16. The cognitive dynamics of computer science cost-effective large scale software development

    CERN Document Server

    De Gyurky, Szabolcs Michael; John Wiley & Sons

    2006-01-01

    This book has three major objectives: To propose an ontology for computer software; To provide a methodology for development of large software systems to cost and schedule that is based on the ontology; To offer an alternative vision regarding the development of truly autonomous systems.

  17. The acoustic environment in large HTGR's

    International Nuclear Information System (INIS)

    Burton, T.E.

    1979-01-01

    Well-known techniques for estimating acoustic vibration of structures have been applied to a General Atomic high-temperature gas-cooled reactor (HTGR) design. It is shown that one must evaluate internal loss factors for both fluid and structure modes, as well as radiation loss factors, to avoid large errors in estimated structural response. At any frequency above 1350 rad/s there are generally at least 20 acoustic modes contributing to acoustic pressure, so statistical energy analysis may be employed. But because the gas circuit consists mainly of high-aspect-ratio cavities, reverberant fields are nowhere isotropic below 7500 rad/s, and in some regions are not isotropic below 60 000 rad/s. In comparison with isotropic reverberant fields, these anistropic fields enhance the radiation efficiencies of some structural modes at low frequencies, but have surprisingly little effect at most frequencies. The efficiency of a dipole sound source depends upon its orientation. (Auth.)

  18. Gastrointestinal absorption of large amounts of plutonium. Effect of valency state on transfer

    International Nuclear Information System (INIS)

    Lataillade, G.; Duserre, C.; Metivier, H.; Madic, C.; CEA Centre d'Etudes Nucleaires de Fontenay-aux-Roses, 92

    1989-01-01

    The gastrointestinal absorption of Pu, ingested in valency state III, IV, V or VI was studied in baboons. For each state, the absorption of Pu from masses ranging from 1 to 7 mg per kg of body weight was compared with that from masses ranging from 5 to 45 μg per kg of body weight. The mass ingested did not affect the gastrointestinal absorption of Pu(IV) or PU(VI), but for Pu(V) and to a lesser extent Pu(III), absorption clearly increased about 150-fold and 7-fold respectively, when large masses of Pu were ingested. When small masses were ingested, the valency state did not affect absorption. The increased Pu absorption observed after ingestion of large masses of Pu(V) or (III) might be due to the weak hydrolysis of these valency states. (author)

  19. Surface States Effect on the Large Photoluminescence Redshift in GaN Nanostructures

    KAUST Repository

    Ben Slimane, Ahmed

    2013-01-01

    We report on the large photoluminescence redshift observed in nanostructures fabricated using n-type GaN by ultraviolet (UV) metal-assisted electroless chemical-etching method. The scanning electron microscopy (SEM) characterization showed nanostructures with size dispersion ranging from 10 to 100 nm. We observed the crystalline structure using high resolution transmission electron microscopy (HRTEM) and electron energy loss (EELS) techniques. In contrast to 362 nm UV emission from the GaN epitaxy, the nanostructures emitted violet visible-light in photoluminescence (PL) characterization with increasing optical excitation. An energy band model was presented to shed light on the large PL redshift under the influence of surface states, which resulted in two competing photoluminescence mechanisms depending on excitation conditions.

  20. Effects of Large Area Liquid Lithium Limiters on Spherical Torus Plasmas

    International Nuclear Information System (INIS)

    Kaita, R.; Majeski, R.; Boaz, M.; Efthimion, P.; Gettelfinger, G.; Gray, T.; Hoffman, D.; Jardin, S.; Kugel, H.; Marfuta, P.; Munsat, T.; Neumeyer, C.; Raftopoulos, S.; Soukhanovskii, V.; Spaleta, J.; Taylor, G.; Timberlake, J.; Woolley, R.; Zakharov, L.; Finkenthal, M.; Stutman, D.; Delgado-Aparicio, L.; Seraydarian, R.P.; Antar, G.; Doerner, R.; Luckhardt, S.; Baldwin, M.; Conn, R.W.; Maingi, R.; Menon, M.; Causey, R.; Buchenauer, D.; Ulrickson, M.; Jones, B.; Rodgers, D.

    2004-01-01

    Use of a large-area liquid lithium surface as a first wall has significantly improved the plasma performance in the Current Drive Experiment-Upgrade (CDX-U) at the Princeton Plasma Physics Laboratory. Previous CDX-U experiments with a partially-covered toroidal lithium limiter tray have shown a decrease in impurities and the recycling of hydrogenic species. Improvements in loading techniques have permitted nearly full coverage of the tray surface with liquid lithium. Under these conditions, there was a large drop in the loop voltage needed to sustain the plasma current. The data are consistent with simulations that indicate more stable plasmas having broader current profiles, higher temperatures, and lowered impurities with liquid lithium walls. As further evidence for reduced recycling with a liquid lithium limiter, the gas puffing had to be increased by up to a factor of eight for the same plasma density achieved with an empty toroidal tray limiter

  1. Effects of large area liquid lithium limiters on spherical torus plasmas

    International Nuclear Information System (INIS)

    Kaita, R.; Majeski, R.; Boaz, M.; Efthimion, P.; Gettelfinger, G.; Gray, T.; Hoffman, D.; Jardin, S.; Kugel, H.; Marfuta, P.; Munsat, T.; Neumeyer, C.; Raftopoulos, S.; Soukhanovskii, V.; Spaleta, J.; Taylor, G.; Timberlake, J.; Woolley, R.; Zakharov, L.; Finkenthal, M.; Stutman, D.; Delgado-Aparicio, L.; Seraydarian, R.P.; Antar, G.; Doerner, R.; Luckhardt, S.; Baldwin, M.; Conn, R.W.; Maingi, R.; Menon, M.; Causey, R.; Buchenauer, D.; Ulrickson, M.; Jones, B.; Rodgers, D.

    2005-01-01

    Use of a large-area liquid lithium surface as a limiter has significantly improved the plasma performance in the Current Drive Experiment-Upgrade (CDX-U) at the Princeton Plasma Physics Laboratory. Previous CDX-U experiments with a partially-covered toroidal lithium limiter tray have shown a decrease in impurities and the recycling of hydrogenic species. Improvements in loading techniques have permitted nearly full coverage of the tray surface with liquid lithium. Under these conditions, there was a large drop in the loop voltage needed to sustain the plasma current. The data are consistent with simulations that indicate more stable plasmas having broader current profiles, higher temperatures, and lowered impurities with liquid lithium walls. As further evidence for reduced recycling with a liquid lithium limiter, the gas puffing had to be increased by up to a factor of eight for the same plasma density achieved with an empty toroidal tray limiter

  2. Drastic Pressure Effect on the Extremely Large Magnetoresistance in WTe2: Quantum Oscillation Study.

    Science.gov (United States)

    Cai, P L; Hu, J; He, L P; Pan, J; Hong, X C; Zhang, Z; Zhang, J; Wei, J; Mao, Z Q; Li, S Y

    2015-07-31

    The quantum oscillations of the magnetoresistance under ambient and high pressure have been studied for WTe2 single crystals, in which extremely large magnetoresistance was discovered recently. By analyzing the Shubnikov-de Haas oscillations, four Fermi surfaces are identified, and two of them are found to persist to high pressure. The sizes of these two pockets are comparable, but show increasing difference with pressure. At 0.3 K and in 14.5 T, the magnetoresistance decreases drastically from 1.25×10(5)% under ambient pressure to 7.47×10(3)% under 23.6 kbar, which is likely caused by the relative change of Fermi surfaces. These results support the scenario that the perfect balance between the electron and hole populations is the origin of the extremely large magnetoresistance in WTe2.

  3. Large rotating magnetocaloric effect in ErAlO3 single crystal

    Directory of Open Access Journals (Sweden)

    X. Q. Zhang

    2017-05-01

    Full Text Available Magnetic and magnetocaloric properties of ErAlO3 single crystal were investigated. Magnetization of ErAlO3 shows obvious anisotropy when magnetic field is applied along the a, b and c axes, which leads to large anisotropic magnetic entropy change. In particular, large rotating field entropy change from the b to c axis within the bc plane is obtained and reaches 9.7 J/kg K at 14 K in a field of 5 T. This suggests the possibility of using ErAlO3 single crystal for magnetic refrigerators by rotating its magnetization vector rather than moving it in and out of the magnet.

  4. Drought effects on large fire activity in Canadian and Alaskan forests

    International Nuclear Information System (INIS)

    Xiao Jingfeng; Zhuang Qianlai

    2007-01-01

    Fire is the dominant disturbance in forest ecosystems across Canada and Alaska, and has important implications for forest ecosystems, terrestrial carbon dioxide emissions and the forestry industry. Large fire activity had increased in Canadian and Alaskan forests during the last four decades of the 20th century. Here we combined the Palmer Drought Severity Index and historical large fire databases to demonstrate that Canada and Alaska forest regions experienced summer drying over this time period, and drought during the fire season significantly affected forest fire activity in these regions. Climatic warming, positive geopotential height anomalies and ocean circulation patterns were spatially and temporally convolved in causing drought conditions, which in turn enhanced fuel flammability and thereby indirectly affected fire activity. Future fire regimes will likely depend on drought patterns under global climate change scenarios

  5. Reduction of reabsorption effects in scintillators by employing solutes with large Stokes shifts

    International Nuclear Information System (INIS)

    Harrah, L.A.; Renschler, C.L.

    1986-01-01

    A radiation or high energy particle responsive system is described useful as a scintillator, and comprising, a first component which interacts with the radiation or high energy particle to emit photons in a certain first wavelength range; and at least one additional solute component which absorbs the photons in the first wavelength range and thereupon emits photons in another wavelength range higher than the first range; the improvement wherein at least one of the components absorbs substantially no photons in the wavelength range in which it emits photons, due to large Stokes shift caused by an excited states intramolecular rearrangement, with the proviso that the component having a large Stokes shift is not methyl salicylate or salicyclic acid

  6. Modern Sedimentation along the SE Bangladesh Coast Reveal Surprisingly Low Accumulation Rates

    Science.gov (United States)

    McHugh, C.; Mustaque, S.; Mondal, D. R.; Akhter, S. H.; Iqbal, M.

    2016-12-01

    Recent sediments recovered along the SE coast of Bangladesh, from Teknaf to Cox's Bazar and drainage basin analyses reveal sediment sources and very low sedimentation rates of 1mm/year. These low rates are surprisingly low given that this coast is adjacent to the Ganges-Brahmaputra Delta with a yearly discharge of 1GT. The Teknaf anticline (elevation 200 m), part of the western Burma fold-thrust belt dominates the topography extending across and along the Teknaf peninsula. It is thought to have begun evolving since the Miocene (Alam et al. 2003 & Allen et al. 2008). Presently the anticline foothills on the west are flanked by uplifted terraces, the youngest linked to coseismic displacement during the 1762 earthquake (Mondal et al. 2015), and a narrow beach 60-200 m in width. Petrography, semi-quantitative bulk mineralogy and SEM/EDX analyses were conducted on sediments recovered along the west coast from 1-4 m deep trenches and three 4-8 m deep drill holes. GIS mapping of drainage basins and quartz-feldspar-lithic (QFL) ternary plots based on grain counting show mixing of sediments from multiple sources: Himalayan provenance of metamorphic and igneous origin (garnet-mostly almandine, tourmaline, rutile, kyanite, zircon, sillimanite and clinopyroxene) similar to Uddin et al. (2007); Brahmaputra provenance of igneous and metamorphic origin (amphibole, epidote, plagioclase 40% Na and 60% Ca, apatite, ilmenite, magnetite, Cr-spinel and garnet-mostly grossular,) as indicated by Garzanti et al. (2010) & Rahman et al. (2016) and Burmese sources (cassiterite and wolframite) (Zaw 1990 & Searle et al. 2007). Low sedimentation rates are the result of two main factors: 1. Strong longshore currents from the south-east that interact with high tidal ranges as evidenced by the morphology of sand waves and ridge and runnel landforms along the beach. 2. Streams draining the Teknaf anticline are dry during the winter and during summer monsoon rains, the sediments bypass the narrow

  7. Scale breaking effects in the quark-parton model for large P perpendicular phenomena

    International Nuclear Information System (INIS)

    Baier, R.; Petersson, B.

    1977-01-01

    We discuss how the scaling violations suggested by an asymptotically free parton model, i.e., the Q 2 -dependence of the transverse momentum of partons within hadrons may affect the parton model description of large p perpendicular phenomena. We show that such a mechanism can provide an explanation for the magnitude of the opposite side correlations and their dependence on the trigger momentum. (author)

  8. Isogeometric analysis of free-form Timoshenko curved beams including the nonlinear effects of large deformations

    Science.gov (United States)

    Hosseini, Seyed Farhad; Hashemian, Ali; Moetakef-Imani, Behnam; Hadidimoud, Saied

    2018-03-01

    In the present paper, the isogeometric analysis (IGA) of free-form planar curved beams is formulated based on the nonlinear Timoshenko beam theory to investigate the large deformation of beams with variable curvature. Based on the isoparametric concept, the shape functions of the field variables (displacement and rotation) in a finite element analysis are considered to be the same as the non-uniform rational basis spline (NURBS) basis functions defining the geometry. The validity of the presented formulation is tested in five case studies covering a wide range of engineering curved structures including from straight and constant curvature to variable curvature beams. The nonlinear deformation results obtained by the presented method are compared to well-established benchmark examples and also compared to the results of linear and nonlinear finite element analyses. As the nonlinear load-deflection behavior of Timoshenko beams is the main topic of this article, the results strongly show the applicability of the IGA method to the large deformation analysis of free-form curved beams. Finally, it is interesting to notice that, until very recently, the large deformations analysis of free-form Timoshenko curved beams has not been considered in IGA by researchers.

  9. A comparison of three approaches to compute the effective Reynolds number of the implicit large-eddy simulations

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ye [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thornber, Ben [The Univ. of Sydney, Sydney, NSW (Australia)

    2016-04-12

    Here, the implicit large-eddy simulation (ILES) has been utilized as an effective approach for calculating many complex flows at high Reynolds number flows. Richtmyer–Meshkov instability (RMI) induced flow can be viewed as a homogeneous decaying turbulence (HDT) after the passage of the shock. In this article, a critical evaluation of three methods for estimating the effective Reynolds number and the effective kinematic viscosity is undertaken utilizing high-resolution ILES data. Effective Reynolds numbers based on the vorticity and dissipation rate, or the integral and inner-viscous length scales, are found to be the most self-consistent when compared to the expected phenomenology and wind tunnel experiments.

  10. The effects of a stress-management training program in individuals at risk in the community at large

    NARCIS (Netherlands)

    Timmerman, IGH; Emmelkamp, PMG; Sanderman, R

    In this study we examine the effects of a stress-management training program on individuals without serious (mental) health complaints but with an increased chance of developing them as a consequence of stress. Potential subjects were randomly selected from the community at large and, then screened

  11. Experimental study and large eddy simulation of effect of terrain slope on marginal burning in shrub fuel beds

    Science.gov (United States)

    Xiangyang Zhou; Shankar Mahalingam; David Weise

    2007-01-01

    This paper presents a combined study of laboratory scale fire spread experiments and a three-dimensional large eddy simulation (LES) to analyze the effect of terrain slope on marginal burning behavior in live chaparral shrub fuel beds. Line fire was initiated in single species fuel beds of four common chaparral plants under various fuel bed configurations and ambient...

  12. Forest landscape models, a tool for understanding the effect of the large-scale and long-term landscape processes

    Science.gov (United States)

    Hong S. He; Robert E. Keane; Louis R. Iverson

    2008-01-01

    Forest landscape models have become important tools for understanding large-scale and long-term landscape (spatial) processes such as climate change, fire, windthrow, seed dispersal, insect outbreak, disease propagation, forest harvest, and fuel treatment, because controlled field experiments designed to study the effects of these processes are often not possible (...

  13. Thermal effect-resilient design of large mode area double-cladding Yb-doped photonic crystal fibers

    DEFF Research Database (Denmark)

    Coscelli, Enrico; Poli, Federica; Johansen, Mette Marie

    2013-01-01

    The effects of thermally-induced refractive index change on the guiding properties of different large mode area fibers have been numerically analyzed. A simple but accurate model has been applied to obtain the refractive index change in the fiber cross-section, and a full-vector modal solver base...

  14. The Partially Flipped Classroom: The Effects of Flipping a Module on "Junk Science" in a Large Methods Course

    Science.gov (United States)

    Burgoyne, Stephanie; Eaton, Judy

    2018-01-01

    Flipped classrooms are gaining popularity, especially in psychology statistics courses. However, not all courses lend themselves to a fully flipped design, and some instructors might not want to commit to flipping every class. We tested the effectiveness of flipping just one component (a module on junk science) of a large methods course. We…

  15. Effects of selective logging on large mammal populations in a remote indigenous territory in the northern Peruvian Amazon

    OpenAIRE

    Pedro Mayor; Pedro Pérez-Peña; Mark Bowler; Pablo E. Puertas; Maire Kirkland; Richard Bodmer

    2015-01-01

    We examined the effects of selective timber logging carried out by local indigenous people in remote areas within indigenous territories on the mammal populations of the Yavari-Mirin River basin on the Peru-Brazil border. Recent findings show that habitat change in the study area is minimal, and any effect of logging activities on large mammal populations is highly likely to be the result of hunting associated with logging operations. We used hunting registers to estimate the monthly and year...

  16. Large-scale brain network coupling predicts acute nicotine abstinence effects on craving and cognitive function.

    Science.gov (United States)

    Lerman, Caryn; Gu, Hong; Loughead, James; Ruparel, Kosha; Yang, Yihong; Stein, Elliot A

    2014-05-01

    Interactions of large-scale brain networks may underlie cognitive dysfunctions in psychiatric and addictive disorders. To test the hypothesis that the strength of coupling among 3 large-scale brain networks--salience, executive control, and default mode--will reflect the state of nicotine withdrawal (vs smoking satiety) and will predict abstinence-induced craving and cognitive deficits and to develop a resource allocation index (RAI) that reflects the combined strength of interactions among the 3 large-scale networks. A within-subject functional magnetic resonance imaging study in an academic medical center compared resting-state functional connectivity coherence strength after 24 hours of abstinence and after smoking satiety. We examined the relationship of abstinence-induced changes in the RAI with alterations in subjective, behavioral, and neural functions. We included 37 healthy smoking volunteers, aged 19 to 61 years, for analyses. Twenty-four hours of abstinence vs smoking satiety. Inter-network connectivity strength (primary) and the relationship with subjective, behavioral, and neural measures of nicotine withdrawal during abstinence vs smoking satiety states (secondary). The RAI was significantly lower in the abstinent compared with the smoking satiety states (left RAI, P = .002; right RAI, P = .04), suggesting weaker inhibition between the default mode and salience networks. Weaker inter-network connectivity (reduced RAI) predicted abstinence-induced cravings to smoke (r = -0.59; P = .007) and less suppression of default mode activity during performance of a subsequent working memory task (ventromedial prefrontal cortex, r = -0.66, P = .003; posterior cingulate cortex, r = -0.65, P = .001). Alterations in coupling of the salience and default mode networks and the inability to disengage from the default mode network may be critical in cognitive/affective alterations that underlie nicotine dependence.

  17. Effect of low dose gamma irradiation on onion yield: Large scale application

    International Nuclear Information System (INIS)

    Al-Oudat, M.

    1993-01-01

    Large scale application of presowing gamma-irradiation of seeds, bulblets and bulbs of onion, performed in 1989, using the doses of 10 Gy for seeds and 1 Gy for bulblets and bulbs. The doses were chosen on the basis of previous experiments. Reliable increases in yield of seeds (19.3%), bulblets (18.9) and bulbs (31.4%) for red variety. and of 22.3% and 23.4% for seeds and bulbs of white variety were obtained. (author). 2 tabs

  18. Large Eddy Simulation of Vertical Axis Wind Turbine wakes; Part II: effects of inflow turbulence

    Science.gov (United States)

    Duponcheel, Matthieu; Chatelain, Philippe; Caprace, Denis-Gabriel; Winckelmans, Gregoire

    2017-11-01

    The aerodynamics of Vertical Axis Wind Turbines (VAWTs) is inherently unsteady, which leads to vorticity shedding mechanisms due to both the lift distribution along the blade and its time evolution. Large-scale, fine-resolution Large Eddy Simulations of the flow past Vertical Axis Wind Turbines have been performed using a state-of-the-art Vortex Particle-Mesh (VPM) method combined with immersed lifting lines. Inflow turbulence with a prescribed turbulence intensity (TI) is injected at the inlet of the simulation from a precomputed synthetic turbulence field obtained using the Mann algorithm. The wake of a standard, medium-solidity, H-shaped machine is simulated for several TI levels. The complex wake development is captured in details and over long distances: from the blades to the near wake coherent vortices, then through the transitional ones to the fully developed turbulent far wake. Mean flow and turbulence statistics are computed over more than 10 diameters downstream of the machine. The sensitivity of the wake topology and decay to the TI level is assessed.

  19. The effects of luminance contribution from large fields to chromatic visual evoked potentials.

    Science.gov (United States)

    Skiba, Rafal M; Duncan, Chad S; Crognale, Michael A

    2014-02-01

    Though useful from a clinical and practical standpoint uniform, large-field chromatic stimuli are likely to contain luminance contributions from retinal inhomogeneities. Such contribution can significantly influence psychophysical thresholds. However, the degree to which small luminance artifacts influence the chromatic VEP has been debated. In particular, claims have been made that band-pass tuning observed in chromatic VEPs result from luminance intrusion. However, there has been no direct evidence presented to support these claims. Recently, large-field isoluminant stimuli have been developed to control for intrusion from retinal inhomogeneities with particular regard to the influence of macular pigment. We report here the application of an improved version of these full-field stimuli to directly test the influence of luminance intrusion on the temporal tuning of the chromatic VEP. Our results show that band-pass tuning persists even when isoluminance is achieved throughout the extent of the stimulus. In addition, small amounts of luminance intrusion affect neither the shape of the temporal tuning function nor the major components of the VEP. These results support the conclusion that the chromatic VEP can depart substantially from threshold psychophysics with regard to temporal tuning and that obtaining a low-pass function is not requisite evidence of selective chromatic activation in the VEP. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Large-Scale Brain Network Coupling Predicts Total Sleep Deprivation Effects on Cognitive Capacity.

    Directory of Open Access Journals (Sweden)

    Yu Lei

    Full Text Available Interactions between large-scale brain networks have received most attention in the study of cognitive dysfunction of human brain. In this paper, we aimed to test the hypothesis that the coupling strength of large-scale brain networks will reflect the pressure for sleep and will predict cognitive performance, referred to as sleep pressure index (SPI. Fourteen healthy subjects underwent this within-subject functional magnetic resonance imaging (fMRI study during rested wakefulness (RW and after 36 h of total sleep deprivation (TSD. Self-reported scores of sleepiness were higher for TSD than for RW. A subsequent working memory (WM task showed that WM performance was lower after 36 h of TSD. Moreover, SPI was developed based on the coupling strength of salience network (SN and default mode network (DMN. Significant increase of SPI was observed after 36 h of TSD, suggesting stronger pressure for sleep. In addition, SPI was significantly correlated with both the visual analogue scale score of sleepiness and the WM performance. These results showed that alterations in SN-DMN coupling might be critical in cognitive alterations that underlie the lapse after TSD. Further studies may validate the SPI as a potential clinical biomarker to assess the impact of sleep deprivation.

  1. Selective exploitation of large pike Esox lucius-Effects on mercury concentrations in fish populations

    International Nuclear Information System (INIS)

    Sharma, Chhatra Mani; Borgstrom, Reidar; Huitfeldt, Jorgen Sinkaberg; Rosseland, Bjorn Olav

    2008-01-01

    The present study outlines two main trends of mercury transfer patterns through the fish community: 1) the Hg concentrations increase with increase in the trophic level, with top predators having the highest concentrations, and 2) a fast growth rate may dilute the concentrations of Hg in fish muscle tissue (growth biodilution). In 2004, an extensive reduction in number of large pike (Esox lucius L.), was initiated by selective gillnet fishing in Lake Arungen, Norway, in order to increase the pike recruitment due to an expected reduction in cannibalism. In this connection, total mercury (THg) concentrations in the fish community were studied both before (2003) and after (2005) the removal of large pike. The δ 15 N signatures and stomach content analyses indicated that pike and perch (Perca fluviatilis L.) occupied the highest trophic position, while roach (Rutilus rutilus (L.)) was at the lower level, and rudd (Scardinius erythrophthalmus L.) at the lowest. The piscivores, pike and perch, had the highest concentrations of THg. The biomagnification rate of THg through the food web in the fish community was 0.163 ( per milleδ 15 N), with the highest uptake rate (0.232) in perch. A significant decrease in THg concentrations was found in all fish species in 2005 compared to 2003. Removal of the top predators in an Hg contaminated lake might thus be an important management tool for reducing Hg levels in fish, thereby reducing health risk to humans

  2. AN INSECURE WILD WEB: A LARGE-SCALE STUDY OF EFFECTIVENESS OF WEB SECURITY MECHANISMS

    Directory of Open Access Journals (Sweden)

    Kailas Patil

    2017-03-01

    Full Text Available This research work presents a large-scale study of the problems in real-world web applications and widely-used mobile browsers. Through a large-scale experiment, we find inconsistencies in Secure Socket Layer (SSL warnings among popular mobile web browsers (over a billion users download. The majority of popular mobile browsers on the Google Play Store either provide incomplete information in SSL warnings shown to users or failed to provide SSL warnings in the presence of security certificate errors, thus making it a difficult task even for a security savvy user to make an informed decision. In addition, we find that 28% of websites are using mixed content. Mixed content means a secure website (https loads a sub resource using insecure HTTP protocol. The mixed content weakens the security of entire website and vulnerable to man-in-the-middle (MITM attacks. Furthermore, we inspected the default behavior of mobile web browsers and report that majority of mobile web browsers allow execution of mixed content in web applications, which implies billions of mobile browser users are vulnerable to eavesdropping and MITM attacks. Based on our findings, we make recommendations for website developers, users and browser vendors.

  3. Earnings management, audit committee effectiveness and the role of blockholders ownership: Evidence from UK large firms

    Directory of Open Access Journals (Sweden)

    Murya Habbash

    2012-12-01

    Full Text Available The existing literature documents that the quality of financial reporting is higher when firms have effective audit committees. However, recent studies find that audit committees are not effective in family firms where agency conflicts arise between controlling and non-controlling shareholders. This study extends the previous findings by investigating the effectiveness of audit committees in firms with similar agency conflicts when one owner obtains effective control of the firm. Compared to firms with a low level of block ownership, high-blockholder firms face less agency problems due to the separation of ownership and management, but more severe agency problems between controlling (blockholders and non-controlling shareholders (minority shareholders. Using a unique hand-collected sample, this study tests the largest 350 UK firms for three years from 2005 to 2007, and shows that firms with effective audit committees have less earnings management. This study also documents that the monitoring effectiveness of audit committees is moderated in firms with high blockholder ownership. The results are not sensitive to the endogeneity test and hold for alternative specifications of both dependent and independent variables. Overall, these findings suggest that audit committees are ineffective in mitigating the majority-minority conflict compared to their effectiveness in reducing owners-managers conflicts. These conclusions, along with some recent similar evidence (e.g., Rose, 2009 and Guthrie and Sokolowsky, 2010, may raise doubts about the monitoring role of blockholders asserted by agency theorists and widely accepted in corporate governance literature.

  4. arXiv Effective horizons, junction conditions and large-scale magnetism

    CERN Document Server

    Giovannini, Massimo

    2017-08-05

    The quantum mechanical generation of hypermagnetic and hyperlectric fields in four-dimensional conformally flat background geometries rests on the simultaneous continuity of the effective horizon and of the extrinsic curvature across the inflationary boundary. The junction conditions for the gauge fields are derived in general terms and corroborated by explicit examples with particular attention to the limit of a sudden (but nonetheless continuous) transition of the effective horizon. After reducing the dynamics to a pair of integral equations related by duality transformations, we compute the power spectra and deduce a novel class of logarithmic corrections which turn out to be, however, numerically insignificant and overwhelmed by the conductivity effects once the gauge modes reenter the effective horizon. In this perspective the magnetogenesis requirements and the role of the postinflationary conductivity are clarified and reappraised. As long as the total duration of the inflationary phase is nearly minim...

  5. Study design considerations in a large COPD trial comparing effects of tiotropium with salmeterol on exacerbations

    NARCIS (Netherlands)

    K-M. Beeh (Kai-Michael); B. Hederer (Bettina); T. Glaab (Thomas); A. Müller (Achim); M.P.M.H. Rutten-van Mölken (Maureen); S. Kesten (Steven); C. Vogelmeier (Claus)

    2009-01-01

    textabstractAbstract Currently available long-acting inhaled bronchodilators (tiotropium, salmeterol, formoterol) have demonstrated beneficial effects on exacerbations in placebo-controlled trials. However, there have been no direct comparisons of these drugs with exacerbations as the primary

  6. Statistical characterization of a large geochemical database and effect of sample size

    Science.gov (United States)

    Zhang, C.; Manheim, F.T.; Hinde, J.; Grossman, J.N.

    2005-01-01

    The authors investigated statistical distributions for concentrations of chemical elements from the National Geochemical Survey (NGS) database of the U.S. Geological Survey. At the time of this study, the NGS data set encompasses 48,544 stream sediment and soil samples from the conterminous United States analyzed by ICP-AES following a 4-acid near-total digestion. This report includes 27 elements: Al, Ca, Fe, K, Mg, Na, P, Ti, Ba, Ce, Co, Cr, Cu, Ga, La, Li, Mn, Nb, Nd, Ni, Pb, Sc, Sr, Th, V, Y and Zn. The goal and challenge for the statistical overview was to delineate chemical distributions in a complex, heterogeneous data set spanning a large geographic range (the conterminous United States), and many different geological provinces and rock types. After declustering to create a uniform spatial sample distribution with 16,511 samples, histograms and quantile-quantile (Q-Q) plots were employed to delineate subpopulations that have coherent chemical and mineral affinities. Probability groupings are discerned by changes in slope (kinks) on the plots. Major rock-forming elements, e.g., Al, Ca, K and Na, tend to display linear segments on normal Q-Q plots. These segments can commonly be linked to petrologic or mineralogical associations. For example, linear segments on K and Na plots reflect dilution of clay minerals by quartz sand (low in K and Na). Minor and trace element relationships are best displayed on lognormal Q-Q plots. These sensitively reflect discrete relationships in subpopulations within the wide range of the data. For example, small but distinctly log-linear subpopulations for Pb, Cu, Zn and Ag are interpreted to represent ore-grade enrichment of naturally occurring minerals such as sulfides. None of the 27 chemical elements could pass the test for either normal or lognormal distribution on the declustered data set. Part of the reasons relate to the presence of mixtures of subpopulations and outliers. Random samples of the data set with successively

  7. Effects of large floods on channel width: recent insights from Italian rivers

    Science.gov (United States)

    Scorpio, Vittoria; Righini, Margherita; Amponsah, William; Crema, Stefano; Ciccarese, Giuseppe; Nardi, Laura; Zoccatelli, Davide; Borga, Marco; Cavalli, Marco; Comiti, Francesco; Corsini, Alessandro; Marchi, Lorenzo; Rinaldi, Massimo; Surian, Nicola

    2017-04-01

    Variations of channel morphology occurring during large flood events (recurrence interval > 50-100 years.) are very often the cause of damages to buildings and infrastructures, as well as of casualties. However, our knowledge of such processes remains poor, as is our capability to predict them. Post-event campaigns documenting channel changes and linking them to hydrological and morphological factors thus bear an enormous value for both the scientific community and river management agencies. We present the results of an analysis on the geomorphic response associated to 4 large floods that occurred between October 2011 and September 2015, affecting several catchments in Northern Italy (Magra-Vara, Trebbia, Nure rivers) and Sardinia (Posada and Mannu di Bitti rivers), characterized by different climatic, lithological and geomorphological settings. The analysis considered more than 400 channel reaches characterized by a drainage area ranging from 39 to 1,100 km2 and featuring a wide range of lateral confinement, mostly within the partly- and unconfined conditions. The approach to flood analysis encompassed: (i) hydrological and hydraulic analysis; (ii) analysis of sediment delivery by landslides to the channel network; (iii) GIS-based and field assessment of morphological channel modifications. For the Nure River flood event (September 2015) a quantitative assessment on average bed level variations was also carried out. Return period for maximum hourly rainfall intensities and peak water discharges exceeded in all basins 100 yr, in some cases even 300 yr. Very high unit peak discharges were estimated, reaching 8.8 m3 s-1km-2 in the Nure River (205 km2) and up to 30 m3 s-1km-2in few Magra River tributaries (5-10 km2). Notable channel widening (post-flood width / pre-flood width > 1.1) occurred in 83% of studied reaches, and it was found more relevant in the channels with narrower initial width, i.e. along the relatively steep tributaries. For these tributaries, the

  8. The effect of parental factors in children with large cup-to-disc ratios.

    Directory of Open Access Journals (Sweden)

    Hae-Young Lopilly Park

    Full Text Available To investigate large cup-to-disc ratios (CDR in children and to determine the relationship between parental CDR and clinical characteristics associated with glaucoma.Two hundred thirty six children aged 6 to 12 years with CDR ≥ 0.6 were enrolled in this study. Subjects were classified into two groups based on parental CDR: disc suspect children with disc suspect (CDR ≥0.6 parents and disc suspect children without disc suspect parents. Ocular variables were compared between the two groups.Of the 236 disc suspect children, 100 (42.4% had at least one disc suspect parent. Intraocular pressure (IOP was higher in disc suspect children with disc suspect parents (16.52±2.66 mmHg than in disc suspect children without disc suspect parents (14.38±2.30 mmHg, p = 0.023. In the group with disc suspect parents, vertical CDR significantly correlated with IOP (R = -0.325, p = 0.001, average retinal nerve fiber layer (RNFL thickness (R = -0.319, p = 0.001, rim area (R = -0.740, p = 0.001, and cup volume (R = 0.499, p = 0.001. However, spherical equivalent (R = 0.333, p = 0.001, AL (R = -0.223, p = 0.009, and disc area (R = 0.325, p = 0.001 significantly correlated with vertical CDR in disc suspect children without disc suspect parents, in contrast to those with disc suspect parents. Larger vertical CDR was associated with the presence of disc suspect parents (p = 0.001, larger disc area (p = 0.001, thinner rim area (p = 0.001, larger average CDR (p = 0.001, and larger cup volume (p = 0.021.Family history of large CDR was a significant factor associated with large vertical CDR in children. In children with disc suspect parents, there were significant correlations between IOP and average RNFL thickness and vertical CDR.

  9. The effect of parental factors in children with large cup-to-disc ratios.

    Science.gov (United States)

    Park, Hae-Young Lopilly; Ha, Min Ji; Shin, Sun Young

    2017-01-01

    To investigate large cup-to-disc ratios (CDR) in children and to determine the relationship between parental CDR and clinical characteristics associated with glaucoma. Two hundred thirty six children aged 6 to 12 years with CDR ≥ 0.6 were enrolled in this study. Subjects were classified into two groups based on parental CDR: disc suspect children with disc suspect (CDR ≥0.6) parents and disc suspect children without disc suspect parents. Ocular variables were compared between the two groups. Of the 236 disc suspect children, 100 (42.4%) had at least one disc suspect parent. Intraocular pressure (IOP) was higher in disc suspect children with disc suspect parents (16.52±2.66 mmHg) than in disc suspect children without disc suspect parents (14.38±2.30 mmHg, p = 0.023). In the group with disc suspect parents, vertical CDR significantly correlated with IOP (R = -0.325, p = 0.001), average retinal nerve fiber layer (RNFL) thickness (R = -0.319, p = 0.001), rim area (R = -0.740, p = 0.001), and cup volume (R = 0.499, p = 0.001). However, spherical equivalent (R = 0.333, p = 0.001), AL (R = -0.223, p = 0.009), and disc area (R = 0.325, p = 0.001) significantly correlated with vertical CDR in disc suspect children without disc suspect parents, in contrast to those with disc suspect parents. Larger vertical CDR was associated with the presence of disc suspect parents (p = 0.001), larger disc area (p = 0.001), thinner rim area (p = 0.001), larger average CDR (p = 0.001), and larger cup volume (p = 0.021). Family history of large CDR was a significant factor associated with large vertical CDR in children. In children with disc suspect parents, there were significant correlations between IOP and average RNFL thickness and vertical CDR.

  10. CP violation in beauty decays the standard model paradigm of large effects

    CERN Document Server

    Bigi, Ikaros I.Y.

    1994-01-01

    The Standard Model contains a natural source for CP asymmetries in weak decays, which is described by the KM mechanism. Beyond \\epsilon _K it generates only elusive manifestations of CP violation in {\\em light-}quark systems. On the other hand it naturally leads to large asymmetries in certain non-leptonic beauty decays. In particular when B^0-\\bar B^0 oscillations are involved, theoretical uncertainties in the hadronic matrix elements either drop out or can be controlled, and one predicts asymmetries well in excess of 10\\% with high parametric reliability. It is briefly described how the KM triangle can be determined experimentally and then subjected to sensitive consistency tests. Any failure would constitute indirect, but unequivocal evidence for the intervention of New Physics; some examples are sketched. Any outcome of a comprehensive program of CP studies in B decays -- short of technical failure -- will provide us with fundamental and unique insights into nature's design.

  11. Promoting Handwashing Behavior: The Effects of Large-scale Community and School-level Interventions.

    Science.gov (United States)

    Galiani, Sebastian; Gertler, Paul; Ajzenman, Nicolas; Orsola-Vidal, Alexandra

    2016-12-01

    This paper analyzes a randomized experiment that uses novel strategies to promote handwashing with soap at critical points in time in Peru. It evaluates a large-scale comprehensive initiative that involved both community and school activities in addition to communication campaigns. The analysis indicates that the initiative was successful in reaching the target audience and in increasing the treated population's knowledge about appropriate handwashing behavior. These improvements translated into higher self-reported and observed handwashing with soap at critical junctures. However, no significant improvements in the health of children under the age of 5 years were observed. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Integration of community structure data reveals observable effects below sediment guideline thresholds in a large estuary

    KAUST Repository

    Tremblay, Louis A.

    2017-04-07

    The sustainable management of estuarine and coastal ecosystems requires robust frameworks due to the presence of multiple physical and chemical stressors. In this study, we assessed whether ecological health decline, based on community structure composition changes along a pollution gradient, occurred at levels below guideline threshold values for copper, zinc and lead. Canonical analysis of principal coordinates (CAP) was used to characterise benthic communities along a metal contamination gradient. The analysis revealed changes in benthic community distribution at levels below the individual guideline values for the three metals. These results suggest that field-based measures of ecological health analysed with multivariate tools can provide additional information to single metal guideline threshold values to monitor large systems exposed to multiple stressors.

  13. Effect of surface roughness on the heating rates of large-angled hypersonic blunt cones

    Science.gov (United States)

    Irimpan, Kiran Joy; Menezes, Viren

    2018-03-01

    Surface-roughness caused by the residue of an ablative Thermal Protection System (TPS) can alter the turbulence level and surface heating rates on a hypersonic re-entry capsule. Large-scale surface-roughness that could represent an ablated TPS, was introduced over the forebody of a 120° apex angle blunt cone, in order to test for its influence on surface heating rates in a hypersonic freestream of Mach 8.8. The surface heat transfer rates measured on smooth and roughened models under the same freestream conditions were compared. The hypersonic flow-fields of the smooth and rough-surfaced models were visualized to analyse the flow physics. Qualitative numerical simulations and pressure measurements were carried out to have an insight into the high-speed flow physics. Experimental observations under moderate Reynolds numbers indicated a delayed transition and an overall reduction of 17-46% in surface heating rates on the roughened model.

  14. The effect of continuous grouping of pigs in large groups on stress response and haematological parameters

    DEFF Research Database (Denmark)

    Damgaard, Birthe Marie; Studnitz, Merete; Jensen, Karin Hjelholt

    2009-01-01

    The consequences of an ‘all in-all out' static group of uniform age vs. a continuously dynamic group with litter introduction and exit every third week were examined with respect to stress response and haematological parameters in large groups of 60 pigs. The experiment included a total of 480 pigs...... from weaning at the age of 4 weeks to the age of 18 weeks after weaning. Limited differences were found in stress and haematological parameters between pigs in dynamic and static groups. The cortisol response to the stress test was increasing with the duration of the stress test in pigs from...... the dynamic group while it was decreasing in the static group. The health condition and the growth performance were reduced in the dynamic groups compared with the static groups. In the dynamic groups the haematological parameters indicated an activation of the immune system characterised by an increased...

  15. A more accurate modeling of the effects of actuators in large space structures

    Science.gov (United States)

    Hablani, H. B.

    1981-01-01

    The paper deals with finite actuators. A nonspinning three-axis stabilized space vehicle having a two-dimensional large structure and a rigid body at the center is chosen for analysis. The torquers acting on the vehicle are modeled as antisymmetric forces distributed in a small but finite area. In the limit they represent point torquers which also are treated as a special case of surface distribution of dipoles. Ordinary and partial differential equations governing the forced vibrations of the vehicle are derived by using Hamilton's principle. Associated modal inputs are obtained for both the distributed moments and the distributed forces. It is shown that the finite torquers excite the higher modes less than the point torquers. Modal cost analysis proves to be a suitable methodology to this end.

  16. Modeling Optical Spectra of Large Organic Systems Using Real-Time Propagation of Semiempirical Effective Hamiltonians.

    Science.gov (United States)

    Ghosh, Soumen; Andersen, Amity; Gagliardi, Laura; Cramer, Christopher J; Govind, Niranjan

    2017-09-12

    We present an implementation of a time-dependent semiempirical method (INDO/S) in NWChem using real-time (RT) propagation to address, in principle, the entire spectrum of valence electronic excitations. Adopting this model, we study the UV/vis spectra of medium-sized systems such as P3B2 and f-coronene, and in addition much larger systems such as ubiquitin in the gas phase and the betanin chromophore in the presence of two explicit solvents (water and methanol). RT-INDO/S provides qualitatively and often quantitatively accurate results when compared with RT- TDDFT or experimental spectra. Even though we only consider the INDO/S Hamiltonian in this work, our implementation provides a framework for performing electron dynamics in large systems using semiempirical Hartree-Fock Hamiltonians in general.

  17. Summary Report: The Shadow effect of large wind farms: measurements, data analysis and modelling

    DEFF Research Database (Denmark)

    Frandsen, Sten Tronæs; Barthelmie, Rebecca Jane; Rathmann, Ole

    It was the goal of the project – by means of data from the demonstration wind farms Horns Rev and Nysted, analyses of these data and modelling – to facilitate prediction of the power losses from a wind farm should a new wind farm be built upwind relative to the prevailing wind direction...... it may appropriate to build new wind farms rather close to the existing wind farms. A relevant question is therefore how far away new wind farms must be placed to avoid too large power losses. Measurements have been carried out for several years at the two sites, and databases have been prepared....... Thus, if different modelling efforts results in comparable results, the quality of the models will be tested outside the physical range where data are available. All considered the project participants find that the project has been immensely successful. The main achievements of the project are...

  18. Polarization effects of supersymmetric QCD in large-Psub(T) direct photon production

    International Nuclear Information System (INIS)

    Antoniadis, I.; Contogouris, A.P.

    1983-05-01

    The linear polarization P (approximately perpendicular minus parallel to the scattering plane) of large-Psub(T) direct photons from unpolarized hadrons is considered. Contrary to standard QCD, where to 0(1) P vanishes, and to 0(αsub(s)) P is very small and changes sign at angle thetasub(cm)=90 0 , it is shown that supersymmetric theories (involving s quarks and light gluinos), already to 0(1), imply a substantial and positive P through a wide range of angles including thetasub(cm)=90 0 . For antipp→γ+X at collider energy and Psub(T)> or approximately 30 GeV, with s quark mass 20 GeV we find P approximately 10% - 5% decreasing with Psub(T). We offer a qualitative understanding and discuss the significance of our results

  19. Assessing the Vulnerability of Large Critical Infrastructure Using Fully-Coupled Blast Effects Modeling

    Energy Technology Data Exchange (ETDEWEB)

    McMichael, L D; Noble, C R; Margraf, J D; Glascoe, L G

    2009-03-26

    Structural failures, such as the MacArthur Maze I-880 overpass in Oakland, California and the I-35 bridge in Minneapolis, Minnesota, are recent examples of our national infrastructure's fragility and serve as an important reminder of such infrastructure in our everyday lives. These two failures, as well as the World Trade Center's collapse and the levee failures in New Orleans, highlight the national importance of protecting our infrastructure as much as possible against acts of terrorism and natural hazards. This paper describes a process for evaluating the vulnerability of critical infrastructure to large blast loads using a fully-coupled finite element approach. A description of the finite element software and modeling technique is discussed along with the experimental validation of the numerical tools. We discuss how such an approach can be used for specific problems such as modeling the progressive collapse of a building.

  20. Far-Field Effects of Large Earthquakes on South Florida's Confined Aquifer

    Science.gov (United States)

    Voss, N. K.; Wdowinski, S.

    2012-12-01

    The similarity between a seismometer and a well hydraulic head record during the passage of a seismic wave has long been documented. This is true even at large distances from earthquake epicenters. South Florida lacks a dense seismic array but does contain a comparably dense network of monitoring wells. The large spatial distribution of deep monitoring wells in South Florida provides an opportunity to study the variance of aquifer response to the passage of seismic waves. We conducted a preliminary study of hydraulic head data, provided by the South Florida Water Management District, from 9 deep wells in South Florida's confined Floridian Aquifer in response to 27 main shock events (January 2010- April 2012) with magnitude 6.9 or greater. Coseismic hydraulic head response was observed in 7 of the 27 events. In order to determine what governs aquifer response to seismic events, earthquake parameters were compared for the 7 positive events. Seismic energy density (SED), an empirical relationship between distance and magnitude, was also used to compare the relative energy between the events at each well site. SED is commonly used as a parameter for establishing thresholds for hydrologic events in the near and intermediate fields. Our analysis yielded a threshold SED for well response in South Florida as 8 x 10-3 J m-3, which is consistent with other studies. Deep earthquakes, with SED above this threshold, did not appear to trigger hydraulic head oscillations. The amplitude of hydraulic head oscillations had no discernable relationship to SED levels. Preliminary results indicate a need for a modification of the SED equation to better accommodate depth in order to be of use in the study of hydrologic response in the far field. We plan to conduct a more comprehensive study incorporating a larger subset (~60) of wells in South Florida in order to further examine the spatial variance of aquifers to the passing of seismic waves as well as better confine the relationship

  1. Small-scale open ocean currents have large effects on wind wave heights

    Science.gov (United States)

    Ardhuin, Fabrice; Gille, Sarah T.; Menemenlis, Dimitris; Rocha, Cesar B.; Rascle, Nicolas; Chapron, Bertrand; Gula, Jonathan; Molemaker, Jeroen

    2017-06-01

    Tidal currents and large-scale oceanic currents are known to modify ocean wave properties, causing extreme sea states that are a hazard to navigation. Recent advances in the understanding and modeling capability of open ocean currents have revealed the ubiquitous presence of eddies, fronts, and filaments at scales 10-100 km. Based on realistic numerical models, we show that these structures can be the main source of variability in significant wave heights at scales less than 200 km, including important variations down to 10 km. Model results are consistent with wave height variations along satellite altimeter tracks, resolved at scales larger than 50 km. The spectrum of significant wave heights is found to be of the order of 70>>2/>(g2>>2>) times the current spectrum, where >> is the spatially averaged significant wave height, >> is the energy-averaged period, and g is the gravity acceleration. This variability induced by currents has been largely overlooked in spite of its relevance for extreme wave heights and remote sensing.Plain Language SummaryWe show that the variations in currents at scales 10 to 100 km are the main source of variations in wave heights at the same scales. Our work uses a combination of realistic numerical models for currents and waves and data from the Jason-3 and SARAL/AltiKa satellites. This finding will be of interest for the investigation of extreme wave heights, remote sensing, and air-sea interactions. As an immediate application, the present results will help constrain the error budget of the up-coming satellite missions, in particular the Surface Water and Ocean Topography (SWOT) mission, and decide how the data will have to be processed to arrive at accurate sea level and wave measurements. It will also help in the analysis of wave measurements by the CFOSAT satellite.

  2. Likelihood of Null Effects of Large NHLBI Clinical Trials Has Increased over Time.

    Directory of Open Access Journals (Sweden)

    Robert M Kaplan

    Full Text Available We explore whether the number of null results in large National Heart Lung, and Blood Institute (NHLBI funded trials has increased over time.We identified all large NHLBI supported RCTs between 1970 and 2012 evaluating drugs or dietary supplements for the treatment or prevention of cardiovascular disease. Trials were included if direct costs >$500,000/year, participants were adult humans, and the primary outcome was cardiovascular risk, disease or death. The 55 trials meeting these criteria were coded for whether they were published prior to or after the year 2000, whether they registered in clinicaltrials.gov prior to publication, used active or placebo comparator, and whether or not the trial had industry co-sponsorship. We tabulated whether the study reported a positive, negative, or null result on the primary outcome variable and for total mortality.17 of 30 studies (57% published prior to 2000 showed a significant benefit of intervention on the primary outcome in comparison to only 2 among the 25 (8% trials published after 2000 (χ2=12.2,df= 1, p=0.0005. There has been no change in the proportion of trials that compared treatment to placebo versus active comparator. Industry co-sponsorship was unrelated to the probability of reporting a significant benefit. Pre-registration in clinical trials.gov was strongly associated with the trend toward null findings.The number NHLBI trials reporting positive results declined after the year 2000. Prospective declaration of outcomes in RCTs, and the adoption of transparent reporting standards, as required by clinicaltrials.gov, may have contributed to the trend toward null findings.

  3. Effect of maternal age on the risk of preterm birth: A large cohort study.

    Science.gov (United States)

    Fuchs, Florent; Monet, Barbara; Ducruet, Thierry; Chaillet, Nils; Audibert, Francois

    2018-01-01

    Maternal age at pregnancy is increasing worldwide as well as preterm birth. However, the association between prematurity and advanced maternal age remains controversial. To evaluate the impact of maternal age on the occurrence of preterm birth after controlling for multiple known confounders in a large birth cohort. Retrospective cohort study using data from the QUARISMA study, a large Canadian randomized controlled trial, which collected data from 184,000 births in 32 hospitals. Inclusion criteria were maternal age over 20 years. Exclusion criteria were multiple pregnancy, fetal malformation and intra-uterine fetal death. Five maternal age categories were defined and compared for maternal characteristics, gestational and obstetric complications, and risk factors for prematurity. Risk factors for preterm birth births were included in the study. Chronic hypertension, assisted reproduction techniques, pre-gestational diabetes, invasive procedure in pregnancy, gestational diabetes and placenta praevia were linearly associated with increasing maternal age whereas hypertensive disorders of pregnancy followed a "U" shaped distribution according to maternal age. Crude rates of preterm birth before 37 weeks followed a "U" shaped curve with a nadir at 5.7% for the group of 30-34 years. In multivariate analysis, the adjusted odds ratio (aOR) of prematurity stratified by age group followed a "U" shaped distribution with an aOR of 1.08 (95%CI; 1.01-1.15) for 20-24 years, and 1.20 (95% CI; 1.06-1.36) for 40 years and older. Confounders found to have the greatest impact were placenta praevia, hypertensive complications, and maternal medical history. Even after adjustment for confounders, advanced maternal age (40 years and over) was associated with preterm birth. A maternal age of 30-34 years was associated with the lowest risk of prematurity.

  4. Topology of Large-Scale Structures of Galaxies in two Dimensions—Systematic Effects

    Science.gov (United States)

    Appleby, Stephen; Park, Changbom; Hong, Sungwook E.; Kim, Juhan

    2017-02-01

    We study the two-dimensional topology of galactic distribution when projected onto two-dimensional spherical shells. Using the latest Horizon Run 4 simulation data, we construct the genus of the two-dimensional field and consider how this statistic is affected by late-time nonlinear effects—principally gravitational collapse and redshift space distortion (RSD). We also consider systematic and numerical artifacts, such as shot noise, galaxy bias, and finite pixel effects. We model the systematics using a Hermite polynomial expansion and perform a comprehensive analysis of known effects on the two-dimensional genus, with a view toward using the statistic for cosmological parameter estimation. We find that the finite pixel effect is dominated by an amplitude drop and can be made less than 1% by adopting pixels smaller than 1/3 of the angular smoothing length. Nonlinear gravitational evolution introduces time-dependent coefficients of the zeroth, first, and second Hermite polynomials, but the genus amplitude changes by less than 1% between z = 1 and z = 0 for smoothing scales {R}{{G}}> 9 {Mpc}/{{h}}. Non-zero terms are measured up to third order in the Hermite polynomial expansion when studying RSD. Differences in the shapes of the genus curves in real and redshift space are small when we adopt thick redshift shells, but the amplitude change remains a significant ˜ { O }(10 % ) effect. The combined effects of galaxy biasing and shot noise produce systematic effects up to the second Hermite polynomial. It is shown that, when sampling, the use of galaxy mass cuts significantly reduces the effect of shot noise relative to random sampling.

  5. Large-scale automatic extraction of side effects associated with targeted anticancer drugs from full-text oncological articles.

    Science.gov (United States)

    Xu, Rong; Wang, QuanQiu

    2015-06-01

    Targeted anticancer drugs such as imatinib, trastuzumab and erlotinib dramatically improved treatment outcomes in cancer patients, however, these innovative agents are often associated with unexpected side effects. The pathophysiological mechanisms underlying these side effects are not well understood. The availability of a comprehensive knowledge base of side effects associated with targeted anticancer drugs has the potential to illuminate complex pathways underlying toxicities induced by these innovative drugs. While side effect association knowledge for targeted drugs exists in multiple heterogeneous data sources, published full-text oncological articles represent an important source of pivotal, investigational, and even failed trials in a variety of patient populations. In this study, we present an automatic process to extract targeted anticancer drug-associated side effects (drug-SE pairs) from a large number of high profile full-text oncological articles. We downloaded 13,855 full-text articles from the Journal of Oncology (JCO) published between 1983 and 2013. We developed text classification, relationship extraction, signaling filtering, and signal prioritization algorithms to extract drug-SE pairs from downloaded articles. We extracted a total of 26,264 drug-SE pairs with an average precision of 0.405, a recall of 0.899, and an F1 score of 0.465. We show that side effect knowledge from JCO articles is largely complementary to that from the US Food and Drug Administration (FDA) drug labels. Through integrative correlation analysis, we show that targeted drug-associated side effects positively correlate with their gene targets and disease indications. In conclusion, this unique database that we built from a large number of high-profile oncological articles could facilitate the development of computational models to understand toxic effects associated with targeted anticancer drugs. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Complex long-distance effects of mutations that confer linezolid resistance in the large ribosomal subunit

    Science.gov (United States)

    Fulle, Simone; Saini, Jagmohan S.; Homeyer, Nadine; Gohlke, Holger

    2015-01-01

    The emergence of multidrug-resistant pathogens will make current antibiotics ineffective. For linezolid, a member of the novel oxazolidinone class of antibiotics, 10 nucleotide mutations in the ribosome have been described conferring resistance. Hypotheses for how these mutations affect antibiotics binding have been derived based on comparative crystallographic studies. However, a detailed description at the atomistic level of how remote mutations exert long-distance effects has remained elusive. Here, we show that the G2032A-C2499A double mutation, located > 10 Å away from the antibiotic, confers linezolid resistance by a complex set of effects that percolate to the binding site. By molecular dynamics simulations and free energy calculations, we identify U2504 and C2452 as spearheads among binding site nucleotides that exert the most immediate effect on linezolid binding. Structural reorganizations within the ribosomal subunit due to the mutations are likely associated with mutually compensating changes in the effective energy. Furthermore, we suggest two main routes of information transfer from the mutation sites to U2504 and C2452. Between these, we observe cross-talk, which suggests that synergistic effects observed for the two mutations arise in an indirect manner. These results should be relevant for the development of oxazolidinone derivatives that are active against linezolid-resistant strains. PMID:26202966

  7. Interactive effects of large- and small-scale sources of feral honey-bees for sunflower in the Argentine Pampas.

    Directory of Open Access Journals (Sweden)

    Agustín Sáez

    Full Text Available Pollinators for animal pollinated crops can be provided by natural and semi-natural habitats, ranging from large vegetation remnants to small areas of non-crop land in an otherwise highly modified landscape. It is unknown, however, how different small- and large-scale habitat patches interact as pollinator sources. In the intensively managed Argentine Pampas, we studied the additive and interactive effects of large expanses (up to 2200 ha of natural habitat, represented by untilled isolated "sierras", and narrow (3-7 m wide strips of semi-natural habitat, represented by field margins, as pollinator sources for sunflower (Helianthus annus. We estimated visitation rates by feral honey-bees, Apis mellifera, and native flower visitors (as a group at 1, 5, 25, 50 and 100 m from a field margin in 17 sunflower fields 0-10 km distant from the nearest sierra. Honey-bees dominated the pollinator assemblage accounting for >90% of all visits to sunflower inflorescences. Honey-bee visitation was strongly affected by proximity to the sierras decreasing by about 70% in the most isolated fields. There was also a decline in honey-bee visitation with distance from the field margin, which was apparent with increasing field isolation, but undetected in fields nearby large expanses of natural habitat. The probability of observing a native visitor decreased with isolation from the sierras, but in other respects visitation by flower visitors other than honey-bees was mostly unaffected by the habitat factors assessed in this study. Overall, we found strong hierarchical and interactive effects between the study large and small-scale pollinator sources. These results emphasize the importance of preserving natural habitats and managing actively field verges in the absence of large remnants of natural habitat for improving pollinator services.

  8. Interactive effects of large- and small-scale sources of feral honey-bees for sunflower in the Argentine Pampas.

    Science.gov (United States)

    Sáez, Agustín; Sabatino, Malena; Aizen, Marcelo A

    2012-01-01

    Pollinators for animal pollinated crops can be provided by natural and semi-natural habitats, ranging from large vegetation remnants to small areas of non-crop land in an otherwise highly modified landscape. It is unknown, however, how different small- and large-scale habitat patches interact as pollinator sources. In the intensively managed Argentine Pampas, we studied the additive and interactive effects of large expanses (up to 2200 ha) of natural habitat, represented by untilled isolated "sierras", and narrow (3-7 m wide) strips of semi-natural habitat, represented by field margins, as pollinator sources for sunflower (Helianthus annus). We estimated visitation rates by feral honey-bees, Apis mellifera, and native flower visitors (as a group) at 1, 5, 25, 50 and 100 m from a field margin in 17 sunflower fields 0-10 km distant from the nearest sierra. Honey-bees dominated the pollinator assemblage accounting for >90% of all visits to sunflower inflorescences. Honey-bee visitation was strongly affected by proximity to the sierras decreasing by about 70% in the most isolated fields. There was also a decline in honey-bee visitation with distance from the field margin, which was apparent with increasing field isolation, but undetected in fields nearby large expanses of natural habitat. The probability of observing a native visitor decreased with isolation from the sierras, but in other respects visitation by flower visitors other than honey-bees was mostly unaffected by the habitat factors assessed in this study. Overall, we found strong hierarchical and interactive effects between the study large and small-scale pollinator sources. These results emphasize the importance of preserving natural habitats and managing actively field verges in the absence of large remnants of natural habitat for improving pollinator services.

  9. Meteorological effects of heat and moisture releases from large power stations (precipitation modification)

    International Nuclear Information System (INIS)

    Patrinos, A.A.N.; Eissenberg, D.M.

    1978-01-01

    The Bowen Electric Generating Plant (Plant Bowen) in Northwest Georgia has been chosen as a test site to investigate the atmospheric effects of cooling towers. This 3,200-MWe coal-fired power plant uses four natural-draft cooling towers and is the largest of U.S. power plants having cooling towers as the sole cooling method. Results are reported from both climatological and field studies. Extensive use has been made of the U.S. National Weather Service (NWS) data accumulated over several decades in Northwest Georgia. Apart from providing preliminary indications of precipitation modification effects, these data have aided in the general understanding of the climatology in the vicinity of Plant Bowen and have paved the way for the field studies currently underway. These field studies, employing a dense network of rain gauges and windsets, are expected to provide the statistical data base necessary to estimate the plant's effect (if any) on precipitation

  10. Large-scale study on effects of metritis on reproduction in Danish Holstein cows

    DEFF Research Database (Denmark)

    Elkjær, Karina; Labouriau, Rodrigo; Ancker, Marie-Louise

    2013-01-01

    production and body condition score as confounders. Metritis was defined as a score of at least 5 (indicating purulent vaginal discharge with abnormal smell) on the Danish uterine score scale (from 0 to 9, used to evaluate vaginal discharge in the first 19d postpartum on all fresh cows in herds participating......A total of 398,237 lactations of Danish Holstein dairy cows were studied with the main objective to investigate the effects of metritis on 2 fertility variables: interval from calving to first insemination (CFI) and nonreturn rate at 56d after first insemination (NR56), adjusting for milk...... in a national herd health program). Cows with metritis in early lactation presented a significant delay in first insemination (hazard ratio of 0.80) and a significantly reduced probability of success at first insemination. The effect of metritis was also present after adjusting for possible effects of body...

  11. Large-scale assessment of Mediterranean marine protected areas effects on fish assemblages.

    Directory of Open Access Journals (Sweden)

    Paolo Guidetti

    Full Text Available Marine protected areas (MPAs were acknowledged globally as effective tools to mitigate the threats to oceans caused by fishing. Several studies assessed the effectiveness of individual MPAs in protecting fish assemblages, but regional assessments of multiple MPAs are scarce. Moreover, empirical evidence on the role of MPAs in contrasting the propagation of non-indigenous-species (NIS and thermophilic species (ThS is missing. We simultaneously investigated here the role of MPAs in reversing the effects of overfishing and in limiting the spread of NIS and ThS. The Mediterranean Sea was selected as study area as it is a region where 1 MPAs are numerous, 2 fishing has affected species and ecosystems, and 3 the arrival of NIS and the northward expansion of ThS took place. Fish surveys were done in well-enforced no-take MPAs (HP, partially-protected MPAs (IP and fished areas (F at 30 locations across the Mediterranean. Significantly higher fish biomass was found in HP compared to IP MPAs and F. Along a recovery trajectory from F to HP MPAs, IP were similar to F, showing that just well enforced MPAs triggers an effective recovery. Within HP MPAs, trophic structure of fish assemblages resembled a top-heavy biomass pyramid. Although the functional structure of fish assemblages was consistent among HP MPAs, species driving the recovery in HP MPAs differed among locations: this suggests that the recovery trajectories in HP MPAs are likely to be functionally similar (i.e., represented by predictable changes in trophic groups, especially fish predators, but the specific composition of the resulting assemblages may depend on local conditions. Our study did not show any effect of MPAs on NIS and ThS. These results may help provide more robust expectations, at proper regional scale, about the effects of new MPAs that may be established in the Mediterranean Sea and other ecoregions worldwide.

  12. Sustained Large-Scale Collective Climate Action Supported by Effective Climate Change Education Practice

    Science.gov (United States)

    Niepold, F., III; Crim, H.; Fiorile, G.; Eldadah, S.

    2017-12-01

    Since 2012, the Climate and Energy Literacy community have realized that as cities, nations and the international community seek solutions to global climate change over the coming decades, a more comprehensive, interdisciplinary approach to climate literacy—one that includes economic and social considerations—will play a vital role in knowledgeable planning, decision-making, and governance. City, county and state leaders are now leading the American response to a changing climate by incubating social innovation to prevail in the face of unprecedented change. Cities are beginning to realize the importance of critical investments to support the policies and strategies that will foster the climate literacy necessary for citizens to understand the urgency of climate actions and to succeed in a resilient post-carbon economy and develop the related workforce. Over decade of federal and non-profit Climate Change Education effective methods have been developed that can support municipality's significant educational capabilities for the purpose of strengthening and scaling city, state, business, and education actions designed to sustain and effectively address this significant social change. Looking to foster the effective and innovative strategies that will enable their communities several networks have collaborated to identify recommendations for effective education and communication practices when working with different types of audiences. U.S. National Science Foundation funded Climate Change Education Partnership (CCEP) Alliance, the National Wildlife Federation, NOAA Climate Program Office, Tri-Agency Climate Change Education Collaborative and the Climate Literacy and Energy Awareness Network (CLEAN) are working to develop a new web portal that will highlight "effective" practices that includes the acquisition and use of climate change knowledge to inform decision-making. The purpose of the web portal is to transfer effective practice to support communities to be

  13. Effectiveness of pentavalent rotavirus vaccine in a large urban population in the United States.

    Science.gov (United States)

    Boom, Julie A; Tate, Jacqueline E; Sahni, Leila C; Rench, Marcia A; Hull, Jennifer J; Gentsch, Jon R; Patel, Manish M; Baker, Carol J; Parashar, Umesh D

    2010-02-01

    The goal was to assess the effectiveness of complete (3-dose) or partial (1- or 2-dose) immunization with pentavalent rotavirus vaccine (RV5) against rotavirus acute gastroenteritis (AGE) in US clinical practice. A case-control evaluation was conducted in February through June 2008 at an emergency department in Houston, Texas. Case patients with rotavirus AGE (N = 90) were identified through testing for rotavirus in fecal specimens obtained from 205 children 15 days through 23 months of age presenting with AGE. Control groups included rotavirus-negative AGE patients (N = 115), concurrently enrolled patients with acute respiratory infection (ARI) (N = 228), and up to 10 age- and zip code-matched children sampled from the Houston-Harris County Immunization Registry (HHCIR) for each case patient >8 months of age. Immunization data were obtained from parent records, health care providers, and/or the HHCIR. Vaccine effectiveness was calculated as 1 minus odds of RV5 vaccination for case patients versus control patients, after adjustment for age at presentation and birth date. The vaccine effectiveness of a complete RV5 series was 89% (95% confidence interval [CI]: 70%-96%) and 85% (95% CI: 55%-95%) with rotavirus-negative AGE and ARI control patients, respectively. Immunization data were available for 44% of case patients (n = 40) from the HHCIR; the estimated 3-dose vaccine effectiveness with these HHCIR control patients was 82% (95% CI: 19%-96%). A complete RV5 series conferred 100% protection (95% CI: 71%-100%) against severe rotavirus disease requiring hospitalization and 96% protection (95% CI: 72%-99%) against disease requiring intravenous hydration. Vaccine effectiveness of 1 and 2 doses against hospitalization and emergency department visits was 69% (95% CI: 13%-89%) and 81% (95% CI: 13%-96%), respectively, using rotavirus-negative AGE and ARI control groups combined. In this setting, a complete series of RV5 was highly effective against severe rotavirus AGE

  14. Large-Scale Assessment of Mediterranean Marine Protected Areas Effects on Fish Assemblages

    Science.gov (United States)

    Guidetti, Paolo; Baiata, Pasquale; Ballesteros, Enric; Di Franco, Antonio; Hereu, Bernat; Macpherson, Enrique; Micheli, Fiorenza; Pais, Antonio; Panzalis, Pieraugusto; Rosenberg, Andrew A.; Zabala, Mikel; Sala, Enric

    2014-01-01

    Marine protected areas (MPAs) were acknowledged globally as effective tools to mitigate the threats to oceans caused by fishing. Several studies assessed the effectiveness of individual MPAs in protecting fish assemblages, but regional assessments of multiple MPAs are scarce. Moreover, empirical evidence on the role of MPAs in contrasting the propagation of non-indigenous-species (NIS) and thermophilic species (ThS) is missing. We simultaneously investigated here the role of MPAs in reversing the effects of overfishing and in limiting the spread of NIS and ThS. The Mediterranean Sea was selected as study area as it is a region where 1) MPAs are numerous, 2) fishing has affected species and ecosystems, and 3) the arrival of NIS and the northward expansion of ThS took place. Fish surveys were done in well-enforced no-take MPAs (HP), partially-protected MPAs (IP) and fished areas (F) at 30 locations across the Mediterranean. Significantly higher fish biomass was found in HP compared to IP MPAs and F. Along a recovery trajectory from F to HP MPAs, IP were similar to F, showing that just well enforced MPAs triggers an effective recovery. Within HP MPAs, trophic structure of fish assemblages resembled a top-heavy biomass pyramid. Although the functional structure of fish assemblages was consistent among HP MPAs, species driving the recovery in HP MPAs differed among locations: this suggests that the recovery trajectories in HP MPAs are likely to be functionally similar (i.e., represented by predictable changes in trophic groups, especially fish predators), but the specific composition of the resulting assemblages may depend on local conditions. Our study did not show any effect of MPAs on NIS and ThS. These results may help provide more robust expectations, at proper regional scale, about the effects of new MPAs that may be established in the Mediterranean Sea and other ecoregions worldwide. PMID:24740479

  15. Unusually large secondary deuterium isotope effect. Thermal trans-cis isomerization of trans-1-phenylcyclohexene

    International Nuclear Information System (INIS)

    Caldwell, R.A.; Misawa, H.; Healy, E.F.; Dewar, M.J.S.

    1987-01-01

    The magnitudes of secondary deuterium isotope effects (SDIE) are generally in the range of 0.9 < k/sub H//k/sub D/ < 1.25, and are often satisfactorily rationalized by the zero-point energy (ZPE) change on going from reactant to transition state due to C-H rehybridization. They now report a far larger SDIE for the title reaction. Its rationalization on the basis of transition state theory suggests that it more closely resembles a primary isotope effect

  16. Effect of small in-plane anisotropy in the large-D phase systems based on Ni{sup 2+} (S=1) ions in Heisenberg antiferromagnetic chains

    Energy Technology Data Exchange (ETDEWEB)

    Rudowicz, Czesław, E-mail: crudowicz@zut.edu.pl

    2014-03-01

    Heisenberg antiferromagnetic chains based on Ni{sup 2+} ions with integer spin S=1 exhibit intriguing behavior, e.g. the Haldane gap phase and the large-D phase. The predicted transitions between the two phases and the Neel phase has generated search for real candidate systems. Crucial to this search is the interplay between the ‘in-plane anisotropy’, i.e. the rhombic zero-field splitting (ZFS) E-term, and the ‘planar anisotropy’, i.e. the axial ZFS D-term. This paper clarifies intricate properties of orthorhombic ZFS Hamiltonians (H{sub ZFS}) and inconsistencies revealed by critical survey of pertinent studies. Reporting the non-standard (D, E) sets with λ=E/D out of the standard range (0, 1/3) alongside the standard sets with λ∝(0, 1/3) indicates that these properties are not recognized. We show that direct comparisons of the non-standard and standard sets are meaningless and lead to incorrect conclusions on the strength of the ‘in-plane anisotropy’ (E) as compared with the ‘planar anisotropy’ (D). To remedy such problems, the ZFSP sets reported for the large-D phase candidate systems are reanalyzed using orthorhombic standardization. The six physically equivalent ZFSP sets are determined in the conventional (D, E) and Stevens (b{sub 2}{sup 0}, b{sub 2}{sup 2}) notation. These considerations help understanding intricacies inherent in orthorhombic H{sub ZFS} and provide consistent data for future modeling of ZFS parameters in the large-D phase and Haldane gap systems.

  17. The Geology of the Marcia Quadrangle of Asteroid Vesta: Assessing the Effects of Large, Young Craters

    Science.gov (United States)

    Williams, David A.; Denevi, Brett W.; Mittlefehldt, David W.; Mest, Scott C.; Schenk, Paul M.; Yingst, R. Aileen; Buczowski, Debra L.; Scully, Jennifer E. C.; Garry, W. Brent; McCord, Thomas B.; hide

    2014-01-01

    We used Dawn spacecraft data to identify and delineate geological units and landforms in the Marcia quadrangle of Vesta as a means to assess the role of the large, relatively young impact craters Marcia (approximately 63 kilometers diameter) and Calpurnia (approximately 53 kilometers diameter) and their surrounding ejecta field on the local geology. We also investigated a local topographic high with a dark-rayed crater named Aricia Tholus, and the impact crater Octavia that is surrounded by a distinctive diffuse mantle. Crater counts and stratigraphic relations suggest that Marcia is the youngest large crater on Vesta, in which a putative impact melt on the crater floor ranges in age between approximately 40 and 60 million years (depending upon choice of chronology system), and Marcia's ejecta blanket ranges in age between approximately 120 and 390 million years (depending upon choice of chronology system). We interpret the geologic units in and around Marcia crater to mark a major Vestan time-stratigraphic event, and that the Marcia Formation is one of the geologically youngest formations on Vesta. Marcia crater reveals pristine bright and dark material in its walls and smooth and pitted terrains on its floor. The smooth unit we interpret as evidence of flow of impact melts and (for the pitted terrain) release of volatiles during or after the impact process. The distinctive dark ejecta surrounding craters Marcia and Calpurnia is enriched in OH- or H-bearing phases and has a variable morphology, suggestive of a complex mixture of impact ejecta and impact melts including dark materials possibly derived from carbonaceous chondrite-rich material. Aricia Tholus, which was originally interpreted as a putative Vestan volcanic edifice based on lower resolution observations, appears to be a fragment of an ancient impact basin rim topped by a dark-rayed impact crater. Octavia crater has a cratering model formation age of approximately 280-990 million years based on counts

  18. Effects of tectonics and large scale climatic changes on the evolutionary history of Hyalomma ticks.

    Science.gov (United States)

    Sands, Arthur F; Apanaskevich, Dmitry A; Matthee, Sonja; Horak, Ivan G; Harrison, Alan; Karim, Shahid; Mohammad, Mohammad K; Mumcuoglu, Kosta Y; Rajakaruna, Rupika S; Santos-Silva, Maria M; Matthee, Conrad A

    2017-09-01

    Hyalomma Koch, 1844 are ixodid ticks that infest mammals, birds and reptiles, to which 27 recognized species occur across the Afrotropical, Palearctic and Oriental regions. Despite their medical and veterinary importance, the evolutionary history of the group is enigmatic. To investigate various taxonomic hypotheses based on morphology, and also some of the mechanisms involved in the diversification of the genus, we sequenced and analysed data derived from two mtDNA fragments, three nuclear DNA genes and 47 morphological characters. Bayesian and Parsimony analyses based on the combined data (2242 characters for 84 taxa) provided maximum resolution and strongly supported the monophyly of Hyalomma and the subgenus Euhyalomma Filippova, 1984 (including H. punt Hoogstraal, Kaiser and Pedersen, 1969). A predicted close evolutionary association was found between morphologically similar H. dromedarii Koch, 1844, H. somalicum Tonelli Rondelli, 1935, H. impeltatum Schulze and Schlottke, 1929 and H. punt, and together they form a sister lineage to H. asiaticum Schulze and Schlottke, 1929, H. schulzei Olenev, 1931 and H. scupense Schulze, 1919. Congruent with morphological suggestions, H. anatolicum Koch, 1844, H. excavatum Koch, 1844 and H. lusitanicum Koch, 1844 form a clade and so also H. glabrum Delpy, 1949, H. marginatum Koch, 1844, H. turanicum Pomerantzev, 1946 and H. rufipes Koch, 1844. Wide scale continental sampling revealed cryptic divergences within African H. truncatum Koch, 1844 and H. rufipes and suggested that the taxonomy of these lineages is in need of a revision. The most basal lineages in Hyalomma represent taxa currently confined to Eurasia and molecular clock estimates suggest that members of the genus started to diverge approximately 36.25 million years ago (Mya). The early diversification event coincides well with the collision of the Indian and Eurasian Plates, an event that was also characterized by large scale faunal turnover in the region. Using S

  19. Effectiveness of Guided Peer Review of Student Essays in a Large Undergraduate Biology Course

    Science.gov (United States)

    Kelly, Lauren

    2015-01-01

    Instructors and researchers often consider peer review an integral part of the writing process, providing myriad benefits for both writers and reviewers. Few empirical studies, however, directly address the relationship between specific methodological changes and peer review effectiveness, especially outside the composition classroom. To…

  20. Statistical Analysis of Large Simulated Yield Datasets for Studying Climate Effects

    NARCIS (Netherlands)

    Makowski, D.; Asseng, S.; Ewert, F.; Bassu, S.; Durand, J.L.; Martre, P.; Adam, M.; Aggarwal, P.K.; Angulo, C.; Baron, C.; Basso, B.; Bertuzzi, P.; Biernath, C.; Boogaard, H.; Boote, K.J.; Brisson, N.; Cammarano, D.; Challinor, A.J.; Conijn, J.G.; Corbeels, M.; Deryng, D.; Sanctis, De G.; Doltra, J.; Gayler, S.; Goldberg, R.; Grassini, P.; Hatfield, J.L.; Heng, L.; Hoek, S.B.; Hooker, J.; Hunt, L.A.; Ingwersen, J.; Izaurralde, C.; Jongschaap, R.E.E.; Jones, J.W.; Kemanian, R.A.; Kersebaum, K.C.; Kim, S.H.; Lizaso, J.; Müller, C.; Naresh Kumar, S.; Nendel, C.; O'Leary, G.J.; Olesen, J.E.; Osborne, T.M.; Palosuo, T.; Pravia, M.V.; Priesack, E.; Ripoche, D.; Rosenzweig, C.; Ruane, A.C.; Sau, F.; Semenov, M.A.; Shcherbak, I.; Steduto, P.; Stöckle, C.O.; Stratonovitch, P.; Streck, T.; Supit, I.; Tao, F.; Teixeira, E.; Thorburn, P.; Timlin, D.; Travasso, M.; Roetter, R.P.; Waha, K.; Wallach, D.; White, J.W.; Williams, J.R.; Wolf, J.

    2015-01-01

    Many simulation studies have been carried out to predict the effect of climate change on crop yield. Typically, in such study, one or several crop models are used to simulate series of crop yield values for different climate scenarios corresponding to different hypotheses of temperature, CO2

  1. Large blastholes in coal mining, canal effects. Barrenos largos en la mineria del carbon, efecto canal

    Energy Technology Data Exchange (ETDEWEB)

    Muniz Hevia, E.; Legorburu Zuazva, V.; Blanco Gonzalez, R. (Union Explosivos Rio Tinto SA, Madrid (Spain))

    1988-01-01

    The 'canal effect' has been known for a long time. It appears only in underground workings. It may be said that the coal industry has suffered from it less than other sectors, perhaps because of its rigorous safety legislation. The Spanish coal mining industry has now been without this phenomenon for many years. 3 refs., 3 figs.

  2. Effects of large herbivores on biodiversity of vegetation and soil microarthropods in low Arctic Greenland

    DEFF Research Database (Denmark)

    Aastrup, Peter; Raundrup, Katrine; Feilberg, Jon

    This report summarizes the results of a project that aims at documenting long term effects of grazing by comparing baseline data inside and outside exclosures. We collected data on vascular plants, mosses, lichens, microarthropod abundance and food-web structure, soil nutrients, decomposition, an...

  3. The Effect of Board Independence on the Sustainability Reporting Practices of Large U.S. Firms \\

    Directory of Open Access Journals (Sweden)

    David N. Herda

    2012-12-01

    firms with a greater proportion of independent board members are: 1 more likely to publish standalone sustainability reports, and 2 more likely to publish higher quality sustainability reports. This paper contributes to prior literature that reports somewhat mixed results on the effect of board independence on voluntary disclosure.

  4. Impact of herbivores on nitrogen cycling : contrasting effects of small and large species

    NARCIS (Netherlands)

    Bakker, ES; Olff, H; Boekhoff, M; Gleichman, JM; Berendse, F

    Herbivores are reported to slow down as well as enhance nutrient cycling in grasslands. These conflicting results may be explained by differences in herbivore type. In this study we focus on herbivore body size as a factor that causes differences in herbivore effects on N cycling. We used an

  5. Impact of herbivores on nitrogen cycling: contrasting effects of small and large species

    NARCIS (Netherlands)

    Bakker, E.S.; Olff, H.; Boekhoff, M.; Gleichman, J.M.; Berendse, F.

    2004-01-01

    Herbivores are reported to slow down as well as enhance nutrient cycling in grasslands. These conflicting results may be explained by differences in herbivore type. In this study we focus on herbivore body size as a factor that causes differences in herbivore effects on N cycling. We used an

  6. Effects of deep basins on structural collapse during large subduction earthquakes

    Science.gov (United States)

    Marafi, Nasser A.; Eberhard, Marc O.; Berman, Jeffrey W.; Wirth, Erin A.; Frankel, Arthur

    2017-01-01

    Deep sedimentary basins are known to increase the intensity of ground motions, but this effect is implicitly considered in seismic hazard maps used in U.S. building codes. The basin amplification of ground motions from subduction earthquakes is particularly important in the Pacific Northwest, where the hazard at long periods is dominated by such earthquakes. This paper evaluates the effects of basins on spectral accelerations, ground-motion duration, spectral shape, and structural collapse using subduction earthquake recordings from basins in Japan that have similar depths as the Puget Lowland basin. For three of the Japanese basins and the Puget Lowland basin, the spectral accelerations were amplified by a factor of 2 to 4 for periods above 2.0 s. The long-duration subduction earthquakes and the effects of basins on spectral shape combined, lower the spectral accelerations at collapse for a set of building archetypes relative to other ground motions. For the hypothetical case in which these motions represent the entire hazard, the archetypes would need to increase up to 3.3 times its strength to compensate for these effects.

  7. Effects of Large Polycyclic Aromatic Hydrocarbons on the Soot Formation in Ethylene-Air Nonpremixed Flames

    KAUST Repository

    Prabhu, S.; Arias, P.G.; Wang, Y.; Gao, Y.; Park, S.; Im, Hong G.; Sarathy, Mani; Chung, Suk-Ho; Lu, T.

    2015-01-01

    This study presents updated comprehensive gas-phase kinetic mechanism and aerosol models to predict soot formation characteristics in ethylene-air nonpremixed flames. A main objective is to investigate the sensitivity of the soot formation rate to various chemical pathways for large polycyclic aromatic hydrocarbons (PAH). In this study, the detailed chemical mechanism was reduced from 397 to 99 species using directed relation graph (DRG) and sensitivity analysis. The method of moments with interpolative closure (MOMIC) was employed for the soot aerosol model. Counterflow nonpremixed flames of pure ethylene at low strain rate sooting conditions are considered, for which the sensitivity of soot formation characteristics with respect to hetrogeneous nucleation is investigated. Results show that higher PAH concentrations result in higher soot nucleation rate, and that the average size of the particles are in good agreement with experimental results. It is found that the nucleation processes (i.e., soot inception) from higher PAH precursors, coronene in particular, is critical for accurate prediction of the overall soot formation.

  8. Effects of Large Polycyclic Aromatic Hydrocarbons on the Soot Formation in Ethylene-Air Nonpremixed Flames

    KAUST Repository

    Prabhu, S.

    2015-03-30

    This study presents updated comprehensive gas-phase kinetic mechanism and aerosol models to predict soot formation characteristics in ethylene-air nonpremixed flames. A main objective is to investigate the sensitivity of the soot formation rate to various chemical pathways for large polycyclic aromatic hydrocarbons (PAH). In this study, the detailed chemical mechanism was reduced from 397 to 99 species using directed relation graph (DRG) and sensitivity analysis. The method of moments with interpolative closure (MOMIC) was employed for the soot aerosol model. Counterflow nonpremixed flames of pure ethylene at low strain rate sooting conditions are considered, for which the sensitivity of soot formation characteristics with respect to hetrogeneous nucleation is investigated. Results show that higher PAH concentrations result in higher soot nucleation rate, and that the average size of the particles are in good agreement with experimental results. It is found that the nucleation processes (i.e., soot inception) from higher PAH precursors, coronene in particular, is critical for accurate prediction of the overall soot formation.

  9. Large magnetocaloric effect of NdGa compound due to successive magnetic transitions

    Science.gov (United States)

    Zheng, X. Q.; Xu, J. W.; Shao, S. H.; Zhang, H.; Zhang, J. Y.; Wang, S. G.; Xu, Z. Y.; Wang, L. C.; Chen, J.; Shen, B. G.

    2018-05-01

    The magnetic behavior and MCE property of NdGa compound were studied in detail. According to the temperature dependence of magnetization (M-T) curve at 0.01 T, two sharp changes were observed at 20 K (TSR) and 42 K (TC), respectively, corresponding to spin reorientation and FM-PM transition. Isothermal magnetization curves up to 5 T at different temperatures were measured and magnetic entropy change (ΔSM) was calculated based on M-H data. Temperature dependences of -ΔSM for a field change of 0-2 T and 0-5 T show that there are two peaks on the curves corresponding to TSR and TC, respectively. The value of the two peaks is 6.4 J/kg K and 15.5 J/kg K for the field change of 0-5 T. Since the two peaks are close, the value of -ΔSM in the temperature range between TSR and TC keeps a large value. The excellent MCE performance of NdGa compound benefits from the existence of two successive magnetic transitions.

  10. MHD instabilities and their effects on plasma confinement in the large helical device plasmas

    International Nuclear Information System (INIS)

    Toi, K.

    2002-01-01

    MHD stability of NBI heated plasmas and impacts of MHD modes on plasma confinement are intensively studied in the Large Helical Device (LHD). Three characteristic MHD instabilities were observed, that is, (1) pressure driven modes excited in the plasma edge, (2) pressure driven mode in the plasma core, and (3) Alfven eigenmodes (AEs) driven by energetic ions. MHD mode excited in the edge region accompanies multiple satellites, and is called Edge Harmonic Modes (EHMs). EHM sometimes has a bursting character. The bursting EHM transiently decreases the stored energy by about 15 percent. In the plasma core region, m=2/n=1 pressure driven mode is typically destabilized. The mode often induces internal collapse in the higher beta regime more than 1 percent. The internal collapse appreciably affects the global confinement. Energetic ion driven AEs are often detected in NBI-heated LHD plasmas. Particular AE with the frequency 8-10 times larger than TAE-frequency was detected in high beta plasmas more than 2 percent. The AE may be related to helicity-induced AE. Excitation of these three types of MHD instabilities and their impacts on plasma confinement are discussed. (author)

  11. Effects of stochastic field lines on the pressure driven MHD instabilities in the Large Helical Device

    Science.gov (United States)

    Ohdachi, Satoshi; Watanabe, Kiyomasa; Sakakibara, Satoru; Suzuki, Yasuhiro; Tsuchiya, Hayato; Ming, Tingfeng; Du, Xiaodi; LHD Expriment Group Team

    2014-10-01

    In the Large Helical Device (LHD), the plasma is surrounded by the so-called magnetic stochastic region, where the Kolmogorov length of the magnetic field lines is very short, from several tens of meters and to thousands meters. Finite pressure gradient are formed in this region and MHD instabilities localized in this region is observed since the edge region of the LHD is always unstable against the pressure driven mode. Therefore, the saturation level of the instabilities is the key issue in order to evaluate the risk of this kind of MHD instabilities. The saturation level depends on the pressure gradient and on the magnetic Reynolds number; there results are similar to the MHD mode in the closed magnetic surface region. The saturation level in the stochastic region is affected also by the stocasticity itself. Parameter dependence of the saturation level of the MHD activities in the region is discussed in detail. It is supported by NIFS budget code ULPP021, 028 and is also partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research 26249144, by the JSPS-NRF-NSFC A3 Foresight Program NSFC: No. 11261140328.

  12. The effect of various parameters of large scale radio propagation models on improving performance mobile communications

    Science.gov (United States)

    Pinem, M.; Fauzi, R.

    2018-02-01

    One technique for ensuring continuity of wireless communication services and keeping a smooth transition on mobile communication networks is the soft handover technique. In the Soft Handover (SHO) technique the inclusion and reduction of Base Station from the set of active sets is determined by initiation triggers. One of the initiation triggers is based on the strong reception signal. In this paper we observed the influence of parameters of large-scale radio propagation models to improve the performance of mobile communications. The observation parameters for characterizing the performance of the specified mobile system are Drop Call, Radio Link Degradation Rate and Average Size of Active Set (AS). The simulated results show that the increase in altitude of Base Station (BS) Antenna and Mobile Station (MS) Antenna contributes to the improvement of signal power reception level so as to improve Radio Link quality and increase the average size of Active Set and reduce the average Drop Call rate. It was also found that Hata’s propagation model contributed significantly to improvements in system performance parameters compared to Okumura’s propagation model and Lee’s propagation model.

  13. Differential effects of allergen challenge on large and small airway reactivity in mice.

    Directory of Open Access Journals (Sweden)

    Chantal Donovan

    Full Text Available The relative contributions of large and small airways to hyperresponsiveness in asthma have yet to be fully assessed. This study used a mouse model of chronic allergic airways disease to induce inflammation and remodelling and determine whether in vivo hyperresponsiveness to methacholine is consistent with in vitro reactivity of trachea and small airways. Balb/C mice were sensitised (days 0, 14 and challenged (3 times/week, 6 weeks with ovalbumin. Airway reactivity was compared with saline-challenged controls in vivo assessing whole lung resistance, and in vitro measuring the force of tracheal contraction and the magnitude/rate of small airway narrowing within lung slices. Increased airway inflammation, epithelial remodelling and fibrosis were evident following allergen challenge. In vivo hyperresponsiveness to methacholine was maintained in isolated trachea. In contrast, methacholine induced slower narrowing, with reduced potency in small airways compared to controls. In vitro incubation with IL-1/TNFα did not alter reactivity. The hyporesponsiveness to methacholine in small airways within lung slices following chronic ovalbumin challenge was unexpected, given hyperresponsiveness to the same agonist both in vivo and in vitro in tracheal preparations. This finding may reflect the altered interactions of small airways with surrounding parenchymal tissue after allergen challenge to oppose airway narrowing and closure.

  14. Uniaxial and biaxial tensioning effects on thin membrane materials. [large space structures

    Science.gov (United States)

    Hinson, W. F.; Goslee, J. W.

    1980-01-01

    Thin laminated membranes are being considered for various surface applications on future large space structural systems. Some of the thin membranes would be stretched across or between structural members with the requirement that the membrane be maintained within specified limits of smoothness which would be dictated by the particular applications such as antenna reflector requirements. The multiaxial tensile force required to maintain the smoothness in the membrane needs to be determined for use in the structure design. Therefore, several types of thicknesses of thin membrane materials have been subjected to varied levels of uniaxial and biaxial tensile loads. During the biaxial tests, deviations of the material surface smoothness were measured by a noncontacting capacitance probe. Basic materials consisted of composites of vacuum deposited aluminum on Mylar and Kapton ranging in thickness from 0.00025 in (0.000635 cm) to 0.002 in (0.00508 cm). Some of the material was reinforced with Kevlar and Nomex scrim. The uniaxial tests determined the material elongation and tensile forces up to ultimate conditions. Biaxial tests indicated that a relatively smooth material surface could be achieved with tensile force of approximately 1 to 15 Newtons per centimeter, depending upon the material thickness and/or reinforcement.

  15. Environmental effects of large discharges of cooling water. Experiences from Swedish nuclear power plants

    International Nuclear Information System (INIS)

    Ehlin, Ulf; Lindahl, Sture; Neuman, Erik; Sandstroem, Olof; Svensson, Jonny

    2009-07-01

    Monitoring the environmental effects of cooling water intake and discharge from Swedish nuclear power stations started at the beginning of the 1960s and continues to this day. In parallel with long-term monitoring, research has provided new knowledge and methods to optimise possible discharge locations and design, and given the ability to forecast their environmental effects. Investigations into the environmental effects of cooling-water are a prerequisite for the issuing of power station operating permits by the environmental authorities. Research projects have been carried out by scientists at universities, while the Swedish Environmental Protection Agency, the Swedish Board of Fisheries, and the Swedish Meteorological and Hydrological Institute, SMHI, are responsible for the greater part of the investigations as well as of the research work. The four nuclear power plants dealt with in this report are Oskarshamn, Ringhals, Barsebaeck and Forsmark. They were taken into operation in 1972, 1975, 1975 and 1980 resp. - a total of 12 reactors. After the closure of the Barsebaeck plants in 2005, ten reactors remain in service. The maximum cooling water discharge from the respective stations was 115, 165, 50 and 135 m 3 /s, which is comparable to the mean flow of an average Swedish river - c:a 150 m 3 /s. The report summarizes studies into the consequences of cooling water intake and discharge. Radiological investigations made at the plants are not covered by this review. The strategy for the investigations was elaborated already at the beginning of the 1960s. The investigations were divided into pre-studies, baseline investigations and monitoring of effects. Pre-studies were partly to gather information for the technical planning and design of cooling water intake and outlet constructions, and partly to survey the hydrographic and ecological situation in the area. Baseline investigations were to carefully map the hydrography and ecology in the area and their natural

  16. A multiwavelength survey of H I-excess galaxies with surprisingly inefficient star formation

    Science.gov (United States)

    Geréb, K.; Janowiecki, S.; Catinella, B.; Cortese, L.; Kilborn, V.

    2018-05-01

    We present the results of a multiwavelength survey of H I-excess galaxies, an intriguing population with large H I reservoirs associated with little current star formation. These galaxies have stellar masses M⋆ > 1010 M⊙, and were identified as outliers in the gas fraction versus NUV-r colour and stellar mass surface density scaling relations based on the GALEX Arecibo SDSS Survey (GASS). We obtained H I interferometry with the Giant Metrewave Radio Telescope, Keck optical long-slit spectroscopy, and deep optical imaging (where available) for four galaxies. Our analysis reveals multiple possible reasons for the H I excess in these systems. One galaxy, AGC 10111, shows an H I disc that is counter-rotating with respect to the stellar bulge, a clear indication of external origin of the gas. Another galaxy appears to host a Malin 1-type disc, where a large specific angular momentum has to be invoked to explain the extreme M_{H I}/M⋆ ratio of 166 per cent. The other two galaxies have early-type morphology with very high gas fractions. The lack of merger signatures (unsettled gas, stellar shells, and streams) in these systems suggests that these gas-rich discs have been built several Gyr ago, but it remains unclear how the gas reservoirs were assembled. Numerical simulations of large cosmological volumes are needed to gain insight into the formation of these rare and interesting systems.

  17. Near-Earth Magnetic Field Effects of Large-Scale Magnetospheric Currents

    DEFF Research Database (Denmark)

    Lühr, Hermann; Xiong, Chao; Olsen, Nils

    2017-01-01

    . Significant progress in interpreting the magnetic fields from the different sources has been achieved thanks to magnetic satellite missions like Ørsted, CHAMP and now Swarm. Of particular interest for this article is a proper representation of the magnetospheric ring current effect. Uncertainties in modelling...... its effect still produce the largest residuals between observations and present-day geomagnetic field models. A lot of progress has been achieved so far, but there are still open issues like the characteristics of the partial ring current. Other currents discussed are those flowing......Magnetospheric currents play an important role in the electrodynamics of near-Earth space. This has been the topic of many space science studies. Here we focus on the magnetic fields they cause close to Earth. Their contribution to the geomagnetic field is the second largest after the core field...

  18. Investigation of radial power and temperature effects in large-scale reflood experiments

    International Nuclear Information System (INIS)

    Motley, F.

    1983-01-01

    The largest reflood test facility in the world has been designed and constructed by the Japan Atomic Energy Research Institute (JAERI). The experimental test facility, known as the Cylindrical Core Test Facility (CCTF), models a full-height core section and the four primary loops of a Pressurized Water Reactor (PWR). The radial power distribution and temperature distribution were varied during the testing program. The test results indicate that the radial effects, while noticeable, do not appreciably alter the overall quenching behavior of the facility. The Transient Reactor Analysis Code (TRAC) correctly predicted the experimental results of several of the tests. The code results indicate that the core flow pattern adjusts multidimensionally to mitigate the effects of increased power or stored energy

  19. Oxidized Mn:Ge magnetic semiconductor: Observation of anomalous Hall effect and large magnetoresistance

    Science.gov (United States)

    Duc Dung, Dang; Choi, Jiyoun; Feng, Wuwei; Cao Khang, Nguyen; Cho, Sunglae

    2018-03-01

    We report on the structural and magneto-transport properties of the as-grown and oxidized Mn:Ge magnetic semiconductors. Based on X-ray diffraction and X-ray photoelectron spectroscopy results, the samples annealed at 650 and 700 °C became fully oxidized and the chemical binding energies of Mn was found to be Mn3O4. Thus, the system became Mn3O4 clusters embedded in Ge1-yOy. The as-grown sample showed positive linear Hall effect and negligible negative magnetoresistance (MR), which trend remained for the sample annealed up to 550 °C. Interestingly, for the samples annealed at above 650 °C, we observed the anomalous Hall effect around 45 K and the giant positive MR, which are respectively 59.2% and 78.5% at 7 kOe annealed at 650 °C and 700 °C.

  20. Effect of energy distribution of laser facula on shafting aligning detection of large assembling set

    Science.gov (United States)

    Cao, Guohua; Su, Chengzhi; Xu, Hongji

    2005-01-01

    This paper introduces the principle of Shafting correction In heavy mechanical manufacturing industry, shipping industry and Nuclear industry, analyzes the effect of distribution of laser light beam spot energy to PSD measure precision. With experiment, we analyze the relation between the different distribution of laser light beam spot energy and PSD measure precision, discuss the method to compensate of shafting correction error caused by the distribution of laser light beam spot energy.

  1. Monetary Losses Do Not Loom Large in Later Life: Age Differences in the Framing Effect

    OpenAIRE

    Joseph A. Mikels; Andrew E. Reed

    2009-01-01

    Studies of the framing effect indicate that individuals are risk averse for decisions framed as gains but risk seeking for decisions framed as losses. However, findings regarding age-related changes in susceptibility to framing are mixed. Recent work demonstrating age-related decreases in reactivity to anticipated monetary losses, but not gains, suggests that older and younger adults might show equivalent risk aversion for gains but discrepant risk seeking for losses. In the current study, ol...

  2. Hydrologic Effects of Global Climate Change on a Large Drained Pine Forest

    Science.gov (United States)

    Devendra M. Amatya; Ge Sun; R. W. Skaggs; G. M Chescheir; J. E. Nettles

    2006-01-01

    A simulation study using a watershed scale forest hydrology model (DRAINWAT) was conducted to evaluate potential effects of climate change on the hydrology of a 3,000 ha managed pine forest in coastal North Carolina. The model was first validated with a five-year (1996-2000) data set fro111 the study site and then run with 50-years (1951-00) of historic weather data...

  3. Large magnetovolume effect induced by ferromagnetic-antiferromagnetic competition in a cobaltite perovskite

    Science.gov (United States)

    Miao, Ping; Lin, Xiaohuan; Koda, Akihiro; Lee, Sanghyun; Ishikawa, Yoshihisa; Torii, Shuki; Yonemura, Masao; Mochiku, Takashi; Sagayama, Hajime; Itoh, Shinichi; Wang, Yinxia; Kadono, Ryosuke; Kamiyama, Takashi

    Materials that show negative thermal expansion (NTE) have significant industrial merit because they can be used to fabricate composites whose dimensions remain invariant upon heating. In some materials, NTE is concomitant with the spontaneous magnetization, known as the magnetovolume effect (MVE). Here we report a new class of MVE material; namely, a layered perovskite PrBaCo2O5.5+ x (0 financed by the S-type project (No. 2014S05) of KEK.

  4. Prediction of temperature and thermal inertia effect in the maturation stage and stockpiling of a large composting mass

    OpenAIRE

    Barrena Gómez, Raquel

    2006-01-01

    A macroscopic non-steady state energy balance was developed and solved for a composting pile of source-selected organic fraction of municipal solid waste during the maturation stage (13,500 kg of compost). Simulated temperature profiles correlated well with temperature experimental data (ranging from 50 to 70 °C) obtained during the maturation process for more than 50 days at full scale. Thermal inertia effect usually found in composting plants and associated to the stockpiling of large compo...

  5. Large intrinsic anomalous Hall effect in half-metallic ferromagnet Co3Sn2S2 with magnetic Weyl fermions

    OpenAIRE

    Wang, Qi; Xu, Yuanfeng; Lou, Rui; Liu, Zhonghao; Li, Man; Huang, Yaobo; Shen, Dawei; Weng, Hongming; Wang, Shancai; Lei, Hechang

    2017-01-01

    The origin of anomalous Hall effect (AHE) in magnetic materials is one of the most intriguing aspect in condensed matter physics and has been controversial for a long time. Recent studies indicate that the intrinsic AHE is closely related to the Berry curvature of occupied electronic states. In a magnetic Weyl semimetal with broken time-reversal symmetry, there are significant contributions on Berry curvature around Weyl nodes, which would lead to a large intrinsic AHE. Here, we report the la...

  6. Assessing Effects of Joining Common Currency Area with Large-Scale DSGE model: A Case of Poland

    OpenAIRE

    Maciej Bukowski; Sebastian Dyrda; Pawe³ Kowal

    2008-01-01

    In this paper we present a large scale dynamic stochastic general equilibrium model, in order to analyze and simulate effects of Euro introduction in Poland. Presented framework is a based on a two-country open economy model, where foreign acts as the Eurozone, and home as a candidate country. We have implemented various types of structural frictions in the open economy block, that generate empirically observable deviations from purchasing power parity rule. We consider such mechanisms as a d...

  7. THE EVALUATION OF SOIL EROSION OFF-SITES EFFECTS IN LARGE BASINS: THE STUDYCASE OF LERMA-CHAPALA WATERSHED, MEXICO

    OpenAIRE

    Helena Cotler A.; Susana Gutierrez D.; Carlos Enriquez G.; Arturo Garrido P.

    2005-01-01

    One of the primary global concerns during the new millennium is the assessment of the impact of accelerated soil erosion on the economy and the environment (Pimentel et al. 1995; Lal, 1995). Erosion damages the site on which it occurs and also has undesirable effects off-site in the larger environment. Erosion moves sediments and nutrients out of the land, creating the two most widespread water pollution problems in the rivers, lakes and dams. The nutrients impact water quality largely throug...

  8. Dynamical screening of AMM and QED effects for large- Z hydrogen-like atoms

    Science.gov (United States)

    Roenko, A. A.; Sveshnikov, K. A.

    2018-01-01

    The effective interaction Δ U AMM of the anomalous magnetic moment (AMM) of an electron with the Coulomb field of an extended nucleus is analyzed. As soon as the q 2 dependence of the electron formfactor F 2( q 2)is taken into account from the beginning, the AMM is found to be dynamically screened at small distances of r ≪ 1/ m. The Δ U AMM effects on the low-lying electronic levels of a superheavy extended nucleus with Zα > 1are analyzed using the nonperturbative approach. The growth rate of the Δ U AMM contribution with increasing Z is shown to be essentially nonmonotonic. At the same time, the energy shifts of electronic levels in the vicinity of the threshold of the lower continuum monotonically decrease in the region Z ≫ Z cr,1 s . The latter result is generalized to the whole self-energy contribution to energy shifts of electronic levels, thus also referring to the possible behavior of QED radiative effects with virtual-photon exchange, considered beyond the framework of the perturbative expansion in Zα.

  9. Effects of bryophyte and lichen cover on permafrost soil temperature at large scale

    Directory of Open Access Journals (Sweden)

    P. Porada

    2016-09-01

    Full Text Available Bryophyte and lichen cover on the forest floor at high latitudes exerts an insulating effect on the ground. In this way, the cover decreases mean annual soil temperature and can protect permafrost soil. Climate change, however, may change bryophyte and lichen cover, with effects on the permafrost state and related carbon balance. It is, therefore, crucial to predict how the bryophyte and lichen cover will react to environmental change at the global scale. To date, current global land surface models contain only empirical representations of the bryophyte and lichen cover, which makes it impractical to predict the future state and function of bryophytes and lichens. For this reason, we integrate a process-based model of bryophyte and lichen growth into the global land surface model JSBACH (Jena Scheme for Biosphere–Atmosphere Coupling in Hamburg. The model simulates bryophyte and lichen cover on upland sites. Wetlands are not included. We take into account the dynamic nature of the thermal properties of the bryophyte and lichen cover and their relation to environmental factors. Subsequently, we compare simulations with and without bryophyte and lichen cover to quantify the insulating effect of the organisms on the soil. We find an average cooling effect of the bryophyte and lichen cover of 2.7 K on temperature in the topsoil for the region north of 50° N under the current climate. Locally, a cooling of up to 5.7 K may be reached. Moreover, we show that using a simple, empirical representation of the bryophyte and lichen cover without dynamic properties only results in an average cooling of around 0.5 K. This suggests that (a bryophytes and lichens have a significant impact on soil temperature in high-latitude ecosystems and (b a process-based description of their thermal properties is necessary for a realistic representation of the cooling effect. The advanced land surface scheme, including a dynamic bryophyte and lichen model, will

  10. Effect of captivity on genetic variance for five traits in the large milkweed bug (Oncopeltus fasciatus).

    Science.gov (United States)

    Rodríguez-Clark, K M

    2004-07-01

    Understanding the changes in genetic variance which may occur as populations move from nature into captivity has been considered important when populations in captivity are used as models of wild ones. However, the inherent significance of these changes has not previously been appreciated in a conservation context: are the methods aimed at founding captive populations with gene diversity representative of natural populations likely also to capture representative quantitative genetic variation? Here, I investigate changes in heritability and a less traditional measure, evolvability, between nature and captivity for the large milkweed bug, Oncopeltus fasciatus, to address this question. Founders were collected from a 100-km transect across the north-eastern US, and five traits (wing colour, pronotum colour, wing length, early fecundity and later fecundity) were recorded for founders and for their offspring during two generations in captivity. Analyses reveal significant heritable variation for some life history and morphological traits in both environments, with comparable absolute levels of evolvability across all traits (0-30%). Randomization tests show that while changes in heritability and total phenotypic variance were highly variable, additive genetic variance and evolvability remained stable across the environmental transition in the three morphological traits (changing 1-2% or less), while they declined significantly in the two life-history traits (5-8%). Although it is unclear whether the declines were due to selection or gene-by-environment interactions (or both), such declines do not appear inevitable: captive populations with small numbers of founders may contain substantial amounts of the evolvability found in nature, at least for some traits.

  11. Effects of Large-Scale Acquisition on Food Insecurity in Sierra Leone

    Directory of Open Access Journals (Sweden)

    Genesis Tambang Yengoh

    2015-07-01

    Full Text Available The recent phenomenon of large-scale acquisition of land for a variety of investment purposes has raised deep concerns over the food security, livelihood and socio-economic development of communities in many regions of the developing world. This study set out to investigate the food security outcomes of land acquisitions in northern Sierra Leone. Using a mixture of quantitative and qualitative research methods, the study measures the severity of food insecurity and hunger, compares the situation of food security before and after the onset of operations of a land investing company, analyzes the food security implications of producing own food versus depending on wage labour for household food needs, and evaluates initiatives put in place by the land investing company to mitigate its food insecurity footprint. Results show an increase in the severity of food insecurity and hunger. Household income from agricultural production has fallen. Employment by the land investing company is limited in terms of the number of people it employs relative to the population of communities in which it operates. Also, wages from employment by the company cannot meet the staple food needs of its employees. The programme that has been put in place by the company to mitigate its food insecurity footprint is failing because of a host of reasons that relate to organization and power relations. In conclusion, rural people are better off producing their own food than depending on the corporate structure of land investment companies. Governments should provide an enabling framework to accommodate this food security need, both in land investment operations that are ongoing and in those that are yet to operate.

  12. Numerical investigation of the effects of large particles on wall-turbulence

    International Nuclear Information System (INIS)

    Pan, Y.; Banerjee, S.

    1997-01-01

    Particle-laden turbulent flows, at average volume fraction less than 4x10 -4 , in open channels are numerically simulated by using a pseudospectral method. The motion of particles, that are large compared with the dissipative length scale, is coupled to the fluid motion by a method that generates a open-quotes virtualclose quotes no-slip boundary on the particle surface by imposition of an external force field on the grid-points enclosed by the particle. Cases for both moving and stationary particles, lying on the wall, are simulated. The investigations focus on particle-turbulence interaction. It is found that particles increase turbulence intensities and Reynolds stress. By examining higher order turbulence statistics and doing a quadrant analysis of the Reynolds stress, it is found that the ejection-sweep cycle is affected emdash primarily through suppression of sweeps by the smaller particles and enhancement of sweep activity by the larger particles. An assessment of the impact of these findings on scalar transfer is made, as enhancement of wall heat/mass transfer rates is a motivation of the overall work on this subject. In the cases considered, comparison of the calculations with an existing experiment was possible, and shows good agreement. At present, due to limitations in available computational resources, this method cannot be used when the particle diameter is smaller than the smallest turbulence scale (e.g. the Kolmogorov length scale) and the volume fraction is of the same order as studied in this paper, i.e. between 10 -3 and 10 -4 . copyright 1997 American Institute of Physics

  13. Study of Cost Effective Large Advanced Pressurized Water Reactors that Employ Passive Safety Features

    International Nuclear Information System (INIS)

    Winters, J.W.; Corletti, M.M.; Hayashi, Y.

    2003-01-01

    A report of DOE sponsored portions of AP1000 Design Certification effort. On December 16, 1999, The United States Nuclear Regulatory Commission issued Design Certification of the AP600 standard nuclear reactor design. This culminated an 8-year review of the AP600 design, safety analysis and probabilistic risk assessment. The AP600 is a 600 MWe reactor that utilizes passive safety features that, once actuated, depend only on natural forces such as gravity and natural circulation to perform all required safety functions. These passive safety systems result in increased plant safety and have also significantly simplified plant systems and equipment, resulting in simplified plant operation and maintenance. The AP600 meets NRC deterministic safety criteria and probabilistic risk criteria with large margins. A summary comparison of key passive safety system design features is provided in Table 1. These key features are discussed due to their importance in affecting the key thermal-hydraulic phenomenon exhibited by the passive safety systems in critical areas. The scope of some of the design changes to the AP600 is described. These changes are the ones that are important in evaluating the passive plant design features embodied in the certified AP600 standard plant design. These design changes are incorporated into the AP1000 standard plant design that Westinghouse is certifying under 10 CFR Part 52. In conclusion, this report describes the results of the representative design certification activities that were partially supported by the Nuclear Energy Research Initiative. These activities are unique to AP1000, but are representative of research activities that must be driven to conclusion to realize successful licensing of the next generation of nuclear power plants in the United States

  14. Magnetism and large magnetocaloric effect in HoFe{sub 2-x}Al{sub x}

    Energy Technology Data Exchange (ETDEWEB)

    Mican, S., E-mail: sever.mican@ubbcluj.ro [Babes-Bolyai University Cluj-Napoca, RO-400084 Cluj-Napoca (Romania); Benea, D., E-mail: diana.benea@phys.ubbcluj.ro [Babes-Bolyai University Cluj-Napoca, RO-400084 Cluj-Napoca (Romania); Tetean, R., E-mail: romulus.tetean@phys.ubbcluj.ro [Babes-Bolyai University Cluj-Napoca, RO-400084 Cluj-Napoca (Romania)

    2013-02-05

    Highlights: Black-Right-Pointing-Pointer Structural, magnetic and magnetocaloric properties of HoFe{sub 2-x}Al{sub x} compounds are reported. Black-Right-Pointing-Pointer Electronic structure calculations show a good agreement between theory and experiment. Black-Right-Pointing-Pointer Magnetic transitions close to room temperature for the Fe-rich samples. Black-Right-Pointing-Pointer High values of the relative cooling power for all of the investigated samples. Black-Right-Pointing-Pointer No hysteresis losses in applied fields of up to 4 T. - Abstract: The structural, magnetic and magnetocaloric properties of several HoFe{sub 2-x}Al{sub x} compounds were investigated. The compounds in the Fe-rich region (0.36 Less-Than-Or-Slanted-Equal-To x Less-Than-Or-Slanted-Equal-To 0.4) crystallize in the cubic MgCu{sub 2} (C15) structure, while for the ones in the intermediate region (0.75 Less-Than-Or-Slanted-Equal-To x Less-Than-Or-Slanted-Equal-To 1.125) the hexagonal MgZn{sub 2} (C14) structure was observed. Electronic structure calculations were performed, showing a good agreement between theory and experiment. The Curie temperatures were found to decrease with Al content. For the Fe-rich compounds, these are close to room temperature, while for the compounds in the intermediate region, transition temperatures are well below 300 K. No magnetic hysteresis was found around the Curie temperature for applied magnetic fields of up to 4 T. All of the investigated compounds undergo a second-order magnetic phase transition at the Curie temperature. A maximum magnetic entropy change value of 7.6 J/kg K was obtained for the sample with x = 1.125, all of the samples displaying rather large RCP values. The possibility of incorporating these materials in magnetic refrigeration devices is discussed.

  15. Cloud Surprises Discovered in Moving NASA EOSDIS Applications into Amazon Web Services… and #6 Will Shock You!

    Science.gov (United States)

    McLaughlin, B. D.; Pawloski, A. W.

    2017-12-01

    NASA ESDIS has been moving a variety of data ingest, distribution, and science data processing applications into a cloud environment over the last 2 years. As expected, there have been a number of challenges in migrating primarily on-premises applications into a cloud-based environment, related to architecture and taking advantage of cloud-based services. What was not expected is a number of issues that were beyond purely technical application re-architectures. From surprising network policy limitations, billing challenges in a government-based cost model, and obtaining certificates in an NASA security-compliant manner to working with multiple applications in a shared and resource-constrained AWS account, these have been the relevant challenges in taking advantage of a cloud model. And most surprising of all… well, you'll just have to wait and see the "gotcha" that caught our entire team off guard!

  16. Large effect of irradiance on hydrogen isotope fractionation of alkenones in Emiliania huxleyi

    Science.gov (United States)

    van der Meer, Marcel T. J.; Benthien, Albert; French, Katherine L.; Epping, Eric; Zondervan, Ingrid; Reichart, Gert-Jan; Bijma, Jelle; Sinninghe Damsté, Jaap S.; Schouten, Stefan

    2015-07-01

    The hydrogen isotopic (δD) composition of long-chain alkenones produced by certain haptophyte algae has been suggested as a potential proxy for reconstructing paleo sea surface salinity. However, environmental parameters other than salinity may also affect the δD of alkenones. We investigated the impact of the level of irradiance on hydrogen isotopic fractionation of alkenones versus growth water by cultivating two strains of the cosmopolitan haptophyte Emiliania huxleyi at different light intensities. The hydrogen isotope fractionation decreased by approximately 40‰ when irradiance was increased from 15 to 200 μmol photons m-2 s-1 above which it was relatively constant. The response is likely a direct effect of photosystem I and II activity as the relationship of the fractionation factor α versus light intensity can be described by an Eilers-Peeters photosynthesis model. This irradiance effect is in agreement with published δD data of alkenones derived from suspended particulate matter collected from different depths in the photic zone of the Gulf of California and the eastern tropical North Pacific. However, haptophyte algae tend to bloom at relatively high light intensities (>500 μmol photons m-2 s-1) occurring at the sea surface, at which hydrogen isotope fractionation is relatively constant and not affected by changes in light intensity. Alkenones accumulating in the sediment are likely mostly derived from these surface water haptophyte blooms, when the largest amount of biomass is produced. Therefore, the observed irradiance effect is unlikely to affect the applicability of the hydrogen isotopic composition of sedimentary long chain alkenones as a proxy for paleosalinity.

  17. Acoustic Studies of the Effects of Environmental Stresses on Marine Mammals in Large Ocean Basins

    Science.gov (United States)

    Sidorovskaia, N.; Ma, B.; Ackleh, A. S.; Tiemann, C.; Ioup, G. E.; Ioup, J. W.

    2014-12-01

    Effects of environmental stresses on deep-diving marine mammal populations have not been studied systematically. Long-term regional passive acoustic monitoring of phonating marine mammals opens opportunities for such studies. This paper presents a unique multi-year study conducted by the Littoral Acoustic Demonstration Center (LADC) in the Northern Gulf of Mexico to understand short-term and long-term effects of anthropogenic stresses on resident populations of endangered sperm and elusive beaked whales. Both species spend many hours each day in deep dives which last about one hour each, so any visual observations for population estimates and behavioral responses are very limited. However, much more cost-efficient acoustic recordings of the phonations during dives on bottom-mounted hydrophones are not skewed by weather conditions or daylight requirements. Broadband passive acoustic data were collected by LADC in 2007 and 2010 at three ranges, 15, 40, and 80 km away from the 2010 Deep Water Horizon oil spill site. Pre-spill and post-spill data processing and comparison allow observing responses of both species to local short-term environmental condition changes and long-term responses to the spill. The short-term effects are studied by correlating daily activity cycles with anthropogenic noise curve daily and weekly cycles at different sites. The strong correlation between the decrease in overall daily activity and the increase in anthropogenic noise level associated with seismic exploration signals can be seen. After streaming raw acoustic data through detection algorithms and detailed assessment of false detection rates, the temporal densities of acoustic phonations are passed into statistical algorithms for resident population estimations. The statistically significant results have shown different regional abundance trends, associated with long-term responses to environmental stresses, for these two species.

  18. Reconstructive Effects of Percutaneous Electrical Stimulation Combined with GGT Composite on Large Bone Defect in Rats

    Directory of Open Access Journals (Sweden)

    Bo-Yin Yang

    2013-01-01

    Full Text Available Previous studies have shown the electromagnetic stimulation improves bone remodeling and bone healing. However, the effect of percutaneous electrical stimulation (ES was not directly explored. The purpose of this study was to evaluate effect of ES on improvement of bone repair. Twenty-four adult male Sprague-Dawley rats were used for cranial implantation. We used a composite comprising genipin cross-linked gelatin mixed with tricalcium phosphate (GGT. Bone defects of all rats were filled with the GGT composites, and the rats were assigned into six groups after operation. The first three groups underwent 4, 8, and 12 weeks of ES, and the anode was connected to the backward of the defect on the neck; the cathode was connected to the front of the defect on the head. Rats were under inhalation anesthesia during the stimulation. The other three groups only received inhalation anesthesia without ES, as control groups. All the rats were examined afterward at 4, 8, and 12 weeks. Radiographic examinations including X-ray and micro-CT showed the progressive bone regeneration in the both ES and non-ES groups. The amount of the newly formed bone increased with the time between implantation and examination in the ES and non-ES groups and was higher in the ES groups. Besides, the new bone growth trended on bilateral sides in ES groups and accumulated in U-shape in non-ES groups. The results indicated that ES could improve bone repair, and the effect is higher around the cathode.

  19. Large electron transfer rate effects from the Duschinsky mixing of vibrations

    DEFF Research Database (Denmark)

    Sando, Gerald M.; Spears, Kenneth G; Hupp, Joseph T

    2001-01-01

    vibrations are very important. The Duschinsky effect arises when two electronic states have vibrational normal mode coordinate systems that are rotated and translated relative to each other. We use a conventional quantum rate model for ET, and the examples include 6-8 vibrations, where two vibrational modes...... are mixed with different amounts of coordinate rotation. The multidimensional Franck-Condon factors (FCF) are computed with standard algorithms and recently developed recursion relations. When displaced, totally symmetric modes are involved, rates with Duschinsky mixing can increase several orders...

  20. Large Converse Piezoelectric Effect Measured on a Single Molecule on a Metallic Surface

    Czech Academy of Sciences Publication Activity Database

    Stetsovych, Oleksandr; Mutombo, Pingo; Švec, Martin; Šámal, Michal; Nejedlý, Jindřich; Císařová, I.; Vázquez, Héctor; Moro-Lagares, María; Berger, Jan; Vacek, Jaroslav; Stará, Irena G.; Starý, Ivo; Jelínek, Pavel

    2018-01-01

    Roč. 140, č. 3 (2018), s. 940-946 ISSN 0002-7863 R&D Projects: GA MŠk LM2015087; GA ČR GA15-19672S; GA ČR GJ17-24210Y; GA ČR(CZ) GA16-08327S Institutional support: RVO:68378271 ; RVO:61388963 Keywords : piezoelectric effect * nc AFM * DFT Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.); Organic chemistry (UOCHB-X) Impact factor: 13.858, year: 2016