WorldWideScience

Sample records for catastrophic disruption threshold

  1. Catastrophic disruption experiments: Recent results

    Science.gov (United States)

    Martelli, G.; Ryan, E. V.; Nakamura, A. M.; Giblin, I.

    1994-01-01

    This paper presents a review of the progress in the field of catastrophic disruption experiments over the past 4 years, since the publication of the review paper by Fujiwara et al. (1989). We describe the development of new techniques to produce shattering impacts relevant to the study of the collisional evolution of the asteroids, and summarize the results from numerous experiments which have been performed to date, using a variety of materials for both the impactor and the targets. Some of these, such as ice-on-ice, loose aggregates and pressurized targets, are quite new and have provided novel and exciting results. Some of the gaps existing previously in the data on fragment ejection-angle distributions, as well as translational and rotational velocity fields (including fine fragments) have been filled, and these new results will be surveyed.

  2. Coping with ecological catastrophe: crossing major thresholds

    Directory of Open Access Journals (Sweden)

    John Cairns, Jr.

    2004-08-01

    Full Text Available The combination of human population growth and resource depletion makes catastrophes highly probable. No long-term solutions to the problems of humankind will be discovered unless sustainable use of the planet is achieved. The essential first step toward this goal is avoiding or coping with global catastrophes that result from crossing major ecological thresholds. Decreasing the number of global catastrophes will reduce the risks associated with destabilizing ecological systems, which could, in turn, destabilize societal systems. Many catastrophes will be local, regional, or national, but even these upheavals will have global consequences. Catastrophes will be the result of unsustainable practices and the misuse of technology. However, avoiding ecological catastrophes will depend on the development of eco-ethics, which is subject to progressive maturation, comments, and criticism. Some illustrative catastrophes have been selected to display some preliminary issues of eco-ethics.

  3. Rotation-Dependent Catastrophic Disruption of Gravitational Aggregates

    CERN Document Server

    Ballouz, Ronald-Louis; Michel, Patrick; Schwartz, Stephen R

    2014-01-01

    We carry out a systematic exploration of the effect of pre-impact rotation on the outcomes of low-speed collisions between planetesimals modeled as gravitational aggregates. We use pkdgrav, a cosmology code adapted to collisional problems and recently enhanced with a new soft-sphere collision algorithm that includes more realistic contact forces. A rotating body has lower effective surface gravity than a non-rotating one and therefore might suffer more mass loss as the result of a collision. What is less well understood, however, is whether rotation systematically increases mass loss on average regardless of the impact trajectory. This has important implications for the efficiency of planet formation via planetesimal growth, and also more generally for the determination of the impact energy threshold for catastrophic disruption (leading to the largest remnant retaining 50% of the original mass), as this has generally only been evaluated for non-spinning bodies. We find that for most collision scenarios, rotat...

  4. Wavelength dependence of catastrophic optical damage threshold in 980nm semiconductor diode lasers

    OpenAIRE

    Lock, D; Sweeney, SJ; Adams, AR

    2003-01-01

    We investigate the wavelength dependence of the catastrophic optical damage current in 980nm lasers. Using high pressure and low temperature techniques, we find an intrinsic dependence of this threshold on wavelength.

  5. Catastrophic disruption in the solar system - Asteroid collisional history, origin of Hirayama families and disruption of small satellites

    Science.gov (United States)

    Davis, D. R.

    1986-01-01

    The process of collisional catastrophic disruption has played a significantly role in structuring the solar system. Diverse populations of bodies such as the asteroid belt, small satellites of Jupiter and Saturn and perhaps even the rings of Saturn have been created or substantially changed by catastrophic distruption. Understanding the outcome of large scale impacts is essential to learning about the early history of the solar system in the asteroid zone and the reason why a planet failed to form there.

  6. Catastrophic Thresholds: A Synthesis of Concepts, Perspectives, and Applications

    Directory of Open Access Journals (Sweden)

    Tamzen K. Stringham

    2010-09-01

    Full Text Available Research reported in this feature identifies a convergence of interpretations regarding the threshold dynamics of complex ecological systems. This convergence has arisen from a diverse set of investigations addressing rangeland ecosystem dynamics, disease transmission, and fluctuations in the populations of insect pests. Effective application of the threshold concept to ecosystem management will require development of more robust linkages between non-equilibrium theory and protocols to identify triggers that initiate threshold conditions, feedback loops that establish system resilience, and developmental trajectories and attributes of potential alternative stable states. Successful implementation of these theory/application linkages has the potential to underpin an operational framework of resilience-based ecosystem management that is founded upon the identification of structural indicators that are correlated with vulnerability or proximity to thresholds, rather than threshold identification per se. Several investigations indicate that thresholds are strongly influenced by scale; multiple cross-scale interactions demonstrate the need for greater knowledge and analyses to address scale-dependent processes, i.e., critical scales and scaling laws. This feature emphasizes the relevance of thresholds and non-equilibrium dynamics in multiple natural resource management applications and in so doing demonstrates the need for a more comprehensive and integrated ecological framework capable of quantitatively assessing dynamics at multiple scales to inform management and policy recommendations for optimal management and risk assessment.

  7. Fragment shapes in impact experiments ranging from cratering to catastrophic disruption

    Science.gov (United States)

    Michikami, Tatsuhiro; Hagermann, Axel; Kadokawa, Tokiyuki; Yoshida, Akifumi; Shimada, Akira; Hasegawa, Sunao; Tsuchiyama, Akira

    2016-01-01

    Laboratory impact experiments have found that impact fragments tend to be elongated. Their shapes, as defined by axes a, b and c, these being the maximum dimensions of the fragment in three mutually orthogonal planes (a ⩾ b ⩾ c), are distributed around mean values of the axial ratios b/a ∼ 0.7 and c/a ∼ 0.5. This corresponds to a:b:c in the simple proportion 2:√2:1. The shape distributions of some boulders on Asteroid Eros, the small- and fast-rotating asteroids (diameter <200 m and rotation period <1 h), and asteroids in young families, are similar to those of laboratory fragments created in catastrophic disruptions. Catastrophic disruption is, however, a process that is different from impact cratering. In order to systematically investigate the shapes of fragments in the range from impact cratering to catastrophic disruption, impact experiments for basalt targets 5-15 cm in size were performed. A total of 28 impact experiments were carried out by firing a spherical nylon projectile (diameter 7.14 mm) perpendicularly into the target surface at velocities of 1.60-7.13 km/s. More than 12,700 fragments with b ⩾ 4 mm generated in the impact experiments were measured. We found that the mean value of c/a in each impact decreases with decreasing impact energy per unit target mass. For instance, the mean value of c/a in an impact cratering event is nearly 0.2, which is considerably smaller than c/a in a catastrophic disruption (∼0.5). The data presented here can provide important evidence to interpret the shapes of asteroids and boulders on asteroid surfaces, and can constrain current interpretations of asteroid formation. As an example, by applying our experimental results to the boulder shapes on Asteroid Itokawa's surface, we can infer that Itokawa's parent body must have experienced a catastrophic disruption.

  8. Super-catastrophic disruption of asteroids at small perihelion distances

    Science.gov (United States)

    Granvik, Mikael; Morbidelli, Alessandro; Jedicke, Robert; Bolin, Bryce; Bottke, William F.; Beshore, Edward; Vokrouhlický, David; Delbò, Marco; Michel, Patrick

    2016-02-01

    Most near-Earth objects came from the asteroid belt and drifted via non-gravitational thermal forces into resonant escape routes that, in turn, pushed them onto planet-crossing orbits. Models predict that numerous asteroids should be found on orbits that closely approach the Sun, but few have been seen. In addition, even though the near-Earth-object population in general is an even mix of low-albedo (less than ten per cent of incident radiation is reflected) and high-albedo (more than ten per cent of incident radiation is reflected) asteroids, the characterized asteroids near the Sun typically have high albedos. Here we report a quantitative comparison of actual asteroid detections and a near-Earth-object model (which accounts for observational selection effects). We conclude that the deficit of low-albedo objects near the Sun arises from the super-catastrophic breakup (that is, almost complete disintegration) of a substantial fraction of asteroids when they achieve perihelion distances of a few tens of solar radii. The distance at which destruction occurs is greater for smaller asteroids, and their temperatures during perihelion passages are too low for evaporation to explain their disappearance. Although both bright and dark (high- and low-albedo) asteroids eventually break up, we find that low-albedo asteroids are more likely to be destroyed farther from the Sun, which explains the apparent excess of high-albedo near-Earth objects and suggests that low-albedo asteroids break up more easily as a result of thermal effects.

  9. The shapes of fragments in hypervelocity impact experiments ranging from cratering to catastrophic disruption

    Science.gov (United States)

    Michikami, T.; Hagermann, A.; Kadokawa, T.; Yoshida, A.; Shimada, A.; Hasegawa, S.; Tsuchiyama, A.

    2015-12-01

    Laboratory impact experiments have found that the shapes of impact fragments as defined by axes a, b and c, these being the maximum dimensions of the fragment in three mutually orthogonal planes (a ≥ b ≥ c) are distributed around mean values of the axial ratios b/a ~0.7 and c/a ~0.5, i.e., corresponding to a : b: c in the simple proportion 2: √2: 1. The shape distributions of some boulders on asteroid Eros, the small- and fast-rotating asteroids (diameter 8 m) on asteroid Itokawa. The mean value of c/a of these boulders is 0.46, which is similar to the value for catastrophic disruption. This implies that the parent body of Itokawa could have experienced a catastrophic disruption.

  10. Observational support for the current sheet catastrophe model of substorm current disruption

    International Nuclear Information System (INIS)

    It has recently been found that a one-dimensional current sheet equilibrium with a non-zero convection electric field, Ey, and a non-zero normal magnetic field component, Bn, can reach a point of catastrophe through either the reduction of the drift velocity, υD = cEy/Bn or the increase of Bn. This point of catastrophe coincides with a value of κA ≅ 0.7, where κA is the self-consistent value of κ = (Rmin/ρAmax)1/2 corresponding to ions of average energy. (Here Rmin is the minimum field-line radius of curvature and ρAmax is the maximum gyroradius for ions of average energy.) The point of catastrophe was found to be preceded by a twisting of the current sheet field-lines into the dawnward direction, i.e., by the development of a y-component of B, with odd symmetry in z, and a sign opposite Bx, where positive x is earthward, positive y is in the dawn-to-dusk direction and positive z is northward. Since the loss of the current sheet would causee the local configuration to become more dipolar, it was suggested that the catastrophic loss of the local current sheet equilibrium could correspond to local current disruption and dipolarization. In this paper, observations of some of the signatures predicted by theory are presented

  11. Catastrophic disruption of asteriods and satellites; Proceedings of the International Workshop, Pisa, Italy, July 30-August 2, 1985

    Science.gov (United States)

    Davis, D. R. (Editor); Farinella, P. (Editor); Paolicchi, P. (Editor); Zappala, V. (Editor)

    1986-01-01

    Theoretical, numerical, and experimental investigations of the violent disruption of asteroids or planetary satellites are discussed in reviews and reports. Topics examined include acceleration techniques and results of experiments simulating catastrophic fragmentation events; laboratory simulations of catastrophic impact; scaling laws for the catastrophic collisions of asteroids; asteroid collisional history, the origin of the Hirayama families, and disruption of small satellites; and the implications of the inferred compositions of a steroids for their collisional evolution. Diagrams, graphs, tables, and a summary of the discussion at the workshop are provided.

  12. The formation of the Baptistina family by catastrophic disruption: Porous versus non-porous parent body

    Science.gov (United States)

    Jutzi, M.; Michel, P.; Benz, W.; Richardson, D. C.

    2009-01-01

    In this paper, we present numerical simulations aimed at reproducing the Baptistina family based on its properties estimated by observations. A previous study by Bottke et al. (2007) indicated that this family is probably at the origin of the K/T impactor, is linked to the CM meteorites and was produced by the disruption of a parent body 170 km in size due to the head-on impact of a projectile 60 km in size at 3 km s-1. This estimate was based on simulations of fragmentation of non-porous materials, while the family was assumed to be of C taxonomic type, which is generally interpreted as being formed from a porous body. Using both a model of fragmentation of non-porous materials, and a model that we developed recently for porous ones, we performed numerical simulations of disruptions aimed at reproducing this family and at analyzing the differences in the outcome between those two models. Our results show that a reasonable match to the estimated size distribution of the real family is produced from the disruption of a porous parent body by the head-on impact of a projectile 54 km in size at 3 km s-1. Thus, our simulations with a model consistent with the assumed dark type of the family requires a smaller projectile than previously estimated, but the difference remains small enough to not affect the proposed scenario of this family history. We then find that the break-up of a porous body leads to different outcomes than the disruption of a non-porous one. The real properties of the Baptistina family still contain large uncertainties, and it remains possible that its formation did not involve the proposed impact conditions. However, the simulations presented here already show some range of outcomes and once the real properties are better constrained, it will be easy to check whether one of them provides a good match.

  13. Catastrophic shifts and lethal thresholds in a propagating front model of unstable tumour progression

    CERN Document Server

    Amor, Daniel R

    2014-01-01

    Unstable dynamics characterizes the evolution of most solid tumors. Because of an increased failure of maintaining genome integrity, a cumulative increase in the levels of gene mutation and loss is observed. Previous work suggests that instability thresholds to cancer progression exist, defining phase transition phenomena separating tumor-winning scenarios from tumor extinction or coexistence phases. Here we present an integral equation approach to the quasispecies dynamics of unstable cancer. The model exhibits two main phases, characterized by either the success or failure of cancer tissue. Moreover, the model predicts that tumor failure can be due to either a reduced selective advantage over healthy cells or excessive instability. We also derive an approximate, analytical solution that predicts the front speed of aggressive tumor populations on the instability space.

  14. Mitotic Spindle Disruption by Alternating Electric Fields Leads to Improper Chromosome Segregation and Mitotic Catastrophe in Cancer Cells

    OpenAIRE

    Moshe Giladi; Schneiderman, Rosa S; Tali Voloshin; Yaara Porat; Mijal Munster; Roni Blat; Shay Sherbo; Zeev Bomzon; Noa Urman; Aviran Itzhaki; Shay Cahal; Anna Shteingauz; Aafia Chaudhry; Kirson, Eilon D.; Uri Weinberg

    2015-01-01

    Tumor Treating Fields (TTFields) are low intensity, intermediate frequency, alternating electric fields. TTFields are a unique anti-mitotic treatment modality delivered in a continuous, noninvasive manner to the region of a tumor. It was previously postulated that by exerting directional forces on highly polar intracellular elements during mitosis, TTFields could disrupt the normal assembly of spindle microtubules. However there is limited evidence directly linking TTFields to an effect on mi...

  15. Deuteron electrodisintegration near threshold of electro-disruption with allowance for meson exchange currents at large transfer momenta

    International Nuclear Information System (INIS)

    The differential cross section of the electrodisintegration of the deuteron near threshold of electro-disruption at large transfer momenta with allowance for meson exchange currents has been investigated. It is shown that at large transfer momenta the results are very sensitive to the choice of the model of NN interaction, parametrization of the electromagnetic form factors and neutron electric form factor. 27 refs., 3 figs

  16. Mitotic Spindle Disruption by Alternating Electric Fields Leads to Improper Chromosome Segregation and Mitotic Catastrophe in Cancer Cells.

    Science.gov (United States)

    Giladi, Moshe; Schneiderman, Rosa S; Voloshin, Tali; Porat, Yaara; Munster, Mijal; Blat, Roni; Sherbo, Shay; Bomzon, Zeev; Urman, Noa; Itzhaki, Aviran; Cahal, Shay; Shteingauz, Anna; Chaudhry, Aafia; Kirson, Eilon D; Weinberg, Uri; Palti, Yoram

    2015-01-01

    Tumor Treating Fields (TTFields) are low intensity, intermediate frequency, alternating electric fields. TTFields are a unique anti-mitotic treatment modality delivered in a continuous, noninvasive manner to the region of a tumor. It was previously postulated that by exerting directional forces on highly polar intracellular elements during mitosis, TTFields could disrupt the normal assembly of spindle microtubules. However there is limited evidence directly linking TTFields to an effect on microtubules. Here we report that TTFields decrease the ratio between polymerized and total tubulin, and prevent proper mitotic spindle assembly. The aberrant mitotic events induced by TTFields lead to abnormal chromosome segregation, cellular multinucleation, and caspase dependent apoptosis of daughter cells. The effect of TTFields on cell viability and clonogenic survival substantially depends upon the cell division rate. We show that by extending the duration of exposure to TTFields, slowly dividing cells can be affected to a similar extent as rapidly dividing cells. PMID:26658786

  17. Low dose mixture effects of endocrine disrupters and their implications for regulatory thresholds in chemical risk assessment.

    Science.gov (United States)

    Kortenkamp, Andreas

    2014-12-01

    Today's chemical exposures are characterised by a widely spread blanket of contamination composed of myriads of chemicals, many of them endocrine disrupters, all at rather low levels. With their focus on considering single chemicals one by one, the approaches used by regulatory bodies worldwide for safety assessments of chemicals cannot keep up with these pollution patterns. A substantial challenge lies in the assessment of combination effects from large numbers of endocrine disrupters and other chemicals, all at low doses. We retrace the development of experimental and conceptual approaches required for assessing low dose mixtures, with an emphasis on work with endocrine disrupting chemicals. We find that nearly 20 years of research has produced good evidence for combination effects at levels around experimental thresholds. One obstacle in deciding on the relevance of this evidence is incomplete information about the range of endocrine-disrupting chemicals that make up combined exposures. These knowledge gaps need to be closed urgently, as is currently discussed under the heading of exposome research. PMID:25244397

  18. Climate catastrophes

    Science.gov (United States)

    Budyko, Mikhail

    1999-05-01

    Climate catastrophes, which many times occurred in the geological past, caused the extinction of large or small populations of animals and plants. Changes in the terrestrial and marine biota caused by the catastrophic climate changes undoubtedly resulted in considerable fluctuations in global carbon cycle and atmospheric gas composition. Primarily, carbon dioxide and other greenhouse gas contents were affected. The study of these catastrophes allows a conclusion that climate system is very sensitive to relatively small changes in climate-forcing factors (transparency of the atmosphere, changes in large glaciations, etc.). It is important to take this conclusion into account while estimating the possible consequences of now occurring anthropogenic warming caused by the increase in greenhouse gas concentration in the atmosphere.

  19. Resounding Catastrophe

    DEFF Research Database (Denmark)

    Kristensen, Thomas Bjørnsten

    2012-01-01

    The article discusses specific aesthetic strategies for articulating and describing the catastrophic event of 9/11 by focusing on its auditory aspects. This is done through a reading of the American media- and sound artist Stephen Vitiello’s work and novelist Don DeLillo’s Falling Man....

  20. Catastrophic medical expenditure risk.

    Science.gov (United States)

    Flores, Gabriela; O'Donnell, Owen

    2016-03-01

    We propose a measure of household exposure to particularly onerous medical expenses. The measure can be decomposed into the probability that medical expenditure exceeds a threshold, the loss due to predictably low consumption of other goods if it does and the further loss arising from the volatility of medical expenses above the threshold. Depending on the choice of threshold, the measure is consistent with a model of reference-dependent utility with loss aversion. Unlike the risk premium, the measure is only sensitive to particularly high expenses, and can identify households that expect to incur such expenses and would benefit from subsidised, but not actuarially fair, insurance. An empirical illustration using data from seven Asian countries demonstrates the importance of taking account of informal insurance and reveals clear differences in catastrophic medical expenditure risk across and within countries. In general, risk is higher among poorer, rural and chronically ill populations. PMID:26812650

  1. Catastrophe medicine; Medecine de catastrophe

    Energy Technology Data Exchange (ETDEWEB)

    Lebreton, A. [Service Technique de l`Energie Electrique et des Grands Barrages (STEEGB), (France)

    1996-12-31

    The `Catastrophe Medicine` congress which took place in Amiens (France) in December 5 to 7 1996 was devoted to the assessment and management of risks and hazards in natural and artificial systems. The methods of risk evaluation and prevision were discussed in the context of dams accidents with the analysis of experience feedbacks and lessons gained from the organisation of emergency plans. Three round table conferences were devoted to the importance of psychological aspects during such major crises. (J.S.)

  2. Seizing Catastrophes

    DEFF Research Database (Denmark)

    Kublitz, Anja

    2013-01-01

    Based on fieldwork among Palestinians in Denmark the article investigates the Palestinian temporality of Nakba that is equivalent to a time of security in the sense that it is concerned with existential threats and emergency action. The Arabic term Nakba literally means catastrophe and is in...... Palestinian national discourse used to designate the Arab-Israeli war of 1948, when more than half of the Palestinian population were expelled from their homeland – a reverse national myth about how Palestine failed to come into being. Yet, according to Palestinians in Denmark, the Nakba cannot be relegated...

  3. Coherent catastrophism

    Science.gov (United States)

    Asher, D. J.; Clube, S. V. M.; Napier, W. M.; Steel, D. I.

    We review the theoretical and observational evidence that, on timescales relevant to mankind, the prime collision hazard is posed by temporally correlated impacts (coherent catastrophism, Δt ˜ 10 2-10 4 yr) rather than random ones (stochastic catastrophism, Δt ˜ 10 5-10 8 yr). The mechanism whereby coherent incursions into and through the terrestrial atmosphere occur is described as being the result of giant cometary bodies arriving in orbits with perihelia in the inner solar system. Hierarchical fragmentation of such large (100 km-plus) bodies — due to thermal stresses near perihelion, collisions in the asteroid belt, or passages through the Jovian Roche radius — results in numerous ˜kilometre-sized objects being left in short-period orbits, and appearing in telescopic searches as Apollo-type asteroids. Many more smaller objects, in the 10-100 metre size range and only recently observed, by the Spacewatch team, are expected to be in replenished clusters in particular orbits as a result of continuing disintegrations of large, differentiated, cometary objects. Gravitational perturbations by Jupiter bring these clusters around to have a node at 1 AU in a cyclic fashion, leading to impacts at certain times of year every few years during active periods lasting a few centuries, such periods being separated by intervals of a few millennia. Furthermore, fragmentations within the hierarchy result in significant bombardment commensurabilities ( Δt ˜ 10-10 2 yr) during active periods occurring at random intervals ( Δt ˜ 10 2-10 3 yr). It appears that the Earth has been subject to such impacts since the break-up of such a comet ˜2×10 4 years ago; currently we are not passing through a high-risk epoch, although some phenomena originating in the products of this break-up have been observed in the 20th century. This most recent hierarchical disintegration, associated with four well-known meteor showers and termed the Taurid Complex, is now recognized as resulting

  4. Reverse Catastrophe

    Directory of Open Access Journals (Sweden)

    Przemysław Czapliński

    2015-01-01

    Full Text Available The principal notion of the article–a “backward catastrophe”– stands for a catastrophe which occurs unseen until it becomes recognized and which broadens its destructive activity until it has been recognized. This concept in the article has been referred to the Shoah. The main thesis is that the recognition of the actual influence of the Holocaust began in Polish culture in the mid-1980s (largely it started with the film by Claude Lanzmann Shoah and the essay by Jan Błoński Biedni Polacy patrzą na getto [“The Poor Poles Look at the Ghetto”], that is when the question: “What happened to the Jews”, assumes the form: “Did the things that happened to the Jews, also happened to the Poles?”. Cognitive and ethical reorientation leads to the revealing of the hidden consequences of the Holocaust reaching as far as the present day and undermining the foundations of collective identity. In order to understand this situation (and adopt potentially preventive actions Polish society should be recognized as a postcatastrophic one.

  5. Catastrophic volcanism

    Science.gov (United States)

    Lipman, Peter W.

    1988-01-01

    Since primitive times, catastrophes due to volcanic activity have been vivid in the mind of man, who knew that his activities in many parts of the world were threatened by lava flows, mudflows, and ash falls. Within the present century, increasingly complex interactions between volcanism and the environment, on scales not previously experienced historically, have been detected or suspected from geologic observations. These include enormous hot pyroclastic flows associated with collapse at source calderas and fed by eruption columns that reached the stratosphere, relations between huge flood basalt eruptions at hotspots and the rifting of continents, devastating laterally-directed volcanic blasts and pyroclastic surges, great volcanic-generated tsunamis, climate modification from volcanic release of ash and sulfur aerosols into the upper atmosphere, modification of ocean circulation by volcanic constructs and attendent climatic implications, global pulsations in intensity of volcanic activity, and perhaps triggering of some intense terrestrial volcanism by planetary impacts. Complex feedback between volcanic activity and additional seemingly unrelated terrestrial processes likely remains unrecognized. Only recently has it become possible to begin to evaluate the degree to which such large-scale volcanic processes may have been important in triggering or modulating the tempo of faunal extinctions and other evolutionary events. In this overview, such processes are examined from the viewpoint of a field volcanologist, rather than as a previous participant in controversies concerning the interrelations between extinctions, impacts, and volcanism.

  6. The reasons for the application of chaos theory to the analysis of catastrophes.

    Science.gov (United States)

    Valery, Kudin

    2014-05-01

    The study of catastrophes is necessary for understanding the nature of the interaction between the individual and the universal in the process of the development of complex systems. Chaos theory, allowing describing adaptation and bifurcation mechanisms for the development of systems, defines the catastrophes as a transition of the system into a different state (change of structure). The previous state of the system is destroyed because of fluctuations, which do not play a role in the development of the system until it reaches the instability region that is inherent to any system. The catastrophe is considered in this theory as a stage in the evolution of the system, and thus emphasizes the importance of catastrophes for the development of any system. We rarely manage events comprehensively, as events are always subject to changes like gas molecules changing the trajectory of motion each moment under the influence of countless blows. The concept of catastrophes is much broader and is generally applicable to any final result of collision of opposing aspirations. Philosophical definition of catastrophes comes down to the destruction of the unity, accompanied by violent collision between different parts, the growing disruption, failure to prevent crossing the dangerous threshold... As a final vertex of action, disaster is not, however, directly its end: the action may continue after the catastrophe, but in the direction that is determined by the character of opposing aspirations. Major catastrophes, which have already destroyed and continue to ravage the world today, come from a superficial use of the laws of the development of complex systems and, in particular, of individual techniques of the chaos theory.

  7. Catastrophes control problem

    International Nuclear Information System (INIS)

    The problem of catastrophe control is discussed. Catastrophe control aims to withdraw responsible engineering constructions out of the catastrophe. The mathematical framework of catastrophes control systems is constructed. It determines the principles of systems filling by the concrete physical contents and, simultaneously, permits to employ modern control methods for the synthesis of optimal withdrawal strategy for protected objects

  8. The Ongoing Catastrophe

    DEFF Research Database (Denmark)

    Kublitz, Anja

    2016-01-01

    as camps. Based on fieldwork among Palestinians in the Danish camps, this article explores why my interlocutors describe their current lives as a catastrophe. Al-Nakba literally means the catastrophe and, in Palestinian national discourse, it is used to designate the event of 1948, when the Palestinians...

  9. Understanding Atmospheric Catastrophes

    Science.gov (United States)

    Chao, Winston C.

    2009-01-01

    The atmosphere, as in other parts of nature, is full of phenomena that involve rapid transitions from one (quasi-) equilibrium state to another--- i.e. catastrophes. These (quasi-) equilibria are the multiple solutions of the same dynamical system. Unlocking the mystery behind a catastrophe reveals not only the physical mechanism responsible for the transition, but also how the (quasi-) equilibria before and after the transition are maintained. Each catastrophe is different, but they do have some common traits. Understanding these common traits is the first step in studying these catastrophes. In this seminar, three examples chosen based on the speaker's research interest--tropical cyclogenesis, stratospheric sudden warming, and monsoon onset--are given to illustrate how atmospheric catastrophes can be studied.

  10. Habitability and cosmic catastrophes

    CERN Document Server

    Hanslmeier, Arnold; McKay, Christopher P

    2008-01-01

    Catastrophic cosmic events such as asteroid impacts appear in the range of some 100 million years and have drastically affected evolution. The author discusses whether and how such events could have occurred in recently found extrasolar planetary systems.

  11. Catastrophic Antiphospholipid Syndrome.

    Science.gov (United States)

    El-Shereef, Rawhya R; El-Abedin, Zein; Abdel Aziz, Rashad; Talat, Ibrahim; Saleh, Mohammed; Abdel-Samia, Hanna; Sameh, Amro; Sharha, Mahmoud

    2016-01-01

    This paper reports one case of successfully treated patients suffering from a rare entity, the catastrophic antiphospholipid syndrome (CAPS). Management of this patient is discussed in detail. PMID:27375916

  12. Catastrophic Antiphospholipid Syndrome

    Directory of Open Access Journals (Sweden)

    Rawhya R. El-Shereef

    2016-01-01

    Full Text Available This paper reports one case of successfully treated patients suffering from a rare entity, the catastrophic antiphospholipid syndrome (CAPS. Management of this patient is discussed in detail.

  13. Entanglement in quantum catastrophes

    CERN Document Server

    Emary, C; Brandes, T; Emary, Clive; Lambert, Neill; Brandes, Tobias

    2005-01-01

    We classify entanglement singularities for various two-mode bosonic systems in terms of catastrophe theory. Employing an abstract phase-space representation, we obtain exact results in limiting cases for the entropy in cusp, butterfly, and two-dimensional catastrophes. We furthermore use numerical results to extract the scaling of the entropy with the non-linearity parameter, and discuss the role of mixing entropies in more complex systems.

  14. Catastrophes in surface scattering

    International Nuclear Information System (INIS)

    Theoretical and experimental studies concerning atom-surface interactions in the energy range from hyperthermal to approximately 100 eV are reported. An extended study of the interaction of low energetic alkalis (sodium and potassium) with a silver crystal is presented. Finally the ultimate experimental result in this research, the first observation of catastrophes in surface scattering, is shown. The results clearly indicate the strength of the catastrophe analysis in gas-surface scattering. 218 refs.; 40 figs.; 170 schemes; 4 tabs

  15. Catastrophic Crop Insurance

    OpenAIRE

    Edwards, William M.

    2003-01-01

    Beginning in 1995 farmers were offered the chance to carry a minimum level of Multiple Peril Crop Insurance (MPCI) coverage at very little cost. This catastrophic or CAT insurance coverage replaces the protection offered to crop producers under federal disaster programs in recent years.

  16. Catastrophic Medical Expenditure Risk

    NARCIS (Netherlands)

    G. Flores (Gabriela); O.A. O'Donnell (Owen)

    2012-01-01

    textabstractMedical expenditure risk can pose a major threat to living standards. We derive decomposable measures of catastrophic medical expenditure risk from reference-dependent utility with loss aversion. We propose a quantile regression based method of estimating risk exposure from cross-section

  17. Catastrophic primary antiphospholipid syndrome

    International Nuclear Information System (INIS)

    Catastrophic antiphospholipid syndrome (CAPLS) was diagnosed in a 64-year-old male who was admitted to our hospital with dyspnea. The clinical and radiological examinations showed pulmonary thromboembolism, and so thromboembolectomy was performed. Abdominal distension rapidly developed several days later, and the abdominal computed tomography (CT) abdominal scan revealed thrombus within the superior mesenteric artery with small bowel and gall bladder distension. Cholecystectomy and jejunoileostomy were performed, and gall bladder necrosis and small bowel infarction were confirmed. The anticardiolipin antibody was positive. Anticoagulant agents and steroids were administered, but the patient expired 4 weeks after surgery due to acute respiratory distress syndrome (ARDS). We report here on a case of catastrophic APLS with manifestations of pulmonary thromboembolism, rapidly progressing GB necrosis and bowel infarction

  18. Catastrophic primary antiphospholipid syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Hun; Byun, Joo Nam [Chosun University Hospital, Gwangju (Korea, Republic of); Ryu, Sang Wan [Miraero21 Medical Center, Gwangju (Korea, Republic of)

    2006-09-15

    Catastrophic antiphospholipid syndrome (CAPLS) was diagnosed in a 64-year-old male who was admitted to our hospital with dyspnea. The clinical and radiological examinations showed pulmonary thromboembolism, and so thromboembolectomy was performed. Abdominal distension rapidly developed several days later, and the abdominal computed tomography (CT) abdominal scan revealed thrombus within the superior mesenteric artery with small bowel and gall bladder distension. Cholecystectomy and jejunoileostomy were performed, and gall bladder necrosis and small bowel infarction were confirmed. The anticardiolipin antibody was positive. Anticoagulant agents and steroids were administered, but the patient expired 4 weeks after surgery due to acute respiratory distress syndrome (ARDS). We report here on a case of catastrophic APLS with manifestations of pulmonary thromboembolism, rapidly progressing GB necrosis and bowel infarction.

  19. Catastrophic Medical Expenditure Risk

    OpenAIRE

    O'Donnell, Owen; Flores, Gabriela

    2012-01-01

    textabstractMedical expenditure risk can pose a major threat to living standards. We derive decomposable measures of catastrophic medical expenditure risk from reference-dependent utility with loss aversion. We propose a quantile regression based method of estimating risk exposure from cross-section data containing information on the means of financing health payments. We estimate medical expenditure risk in seven Asian countries and find it is highest in Laos and China, and is lowest in Mala...

  20. Valuing Catastrophic Citrus Losses

    OpenAIRE

    Adams, Damian C.; Kilmer, Richard L.; Moss, Charles B.; Schmitz, Andrew

    2004-01-01

    Courts are often required to estimate changes in welfare to agricultural operations from catastrophic events. For example, courts must assign damages in lawsuits, such as with pesticide drift cases, or determine "just compensation" when the government takes private land for public use, as with the removal of dairy farms from environmentally sensitive land or destruction of canker-contaminated citrus trees. In economics, the traditional method of quantifying producer losses is estimating chang...

  1. The limits of catastrophe aversion.

    Science.gov (United States)

    Peterson, Martin

    2002-06-01

    We discuss the management of catastrophe-risks from a theoretical point of view. The concept of a catastrophe is informally and formally defined, and a number of desiderata for catastrophe-averse decision rules are introduced. However, the proposed desiderata turn out to be mutually inconsistent. As a consequence of this result, it is argued that the "rigid" form of catastrophe aversion articulated by, for example, the maximin rule, the maximum probable loss rule, (some versions of) the precautionary principle, and the rule proposed in Ekenberg et al. (1997, 2000) should be given up. An alternative form of "non-rigid" catastrophe aversion is considered. PMID:12088231

  2. CATASTROPHIC EVENTS MODELING

    Directory of Open Access Journals (Sweden)

    Ciumas Cristina

    2013-07-01

    Full Text Available This paper presents the emergence and evolution of catastrophe models (cat models. Starting with the present context of extreme weather events and features of catastrophic risk (cat risk we’ll make a chronological illustration from a theoretical point of view of the main steps taken for building such models. In this way the importance of interdisciplinary can be observed. The first cat model considered contains three modules. For each of these indentified modules: hazard, vulnerability and financial losses a detailed overview and also an exemplification of a potential case of an earthquake that measures more than 7 on Richter scale occurring nowadays in Bucharest will be provided. The key areas exposed to earthquake in Romania will be identified. Then, based on past catastrophe data and taking into account present conditions of housing stock, insurance coverage and the population of Bucharest the impact will be quantified by determining potential losses. In order to accomplish this work we consider a scenario with data representing average values for: dwelling’s surface, location, finishing works. On each step we’ll make a reference to the earthquake on March 4 1977 to see what would happen today if a similar event occurred. The value of Bucharest housing stock will be determined taking firstly the market value, then the replacement value and ultimately the real value to quantify potential damages. Through this approach we can find the insurance coverage of potential losses and also the uncovered gap. A solution that may be taken into account by public authorities, for example by Bucharest City Hall will be offered: in case such an event occurs the impossibility of paying compensations to insured people, rebuilding infrastructure and public buildings and helping the suffering persons should be avoided. An actively public-private partnership should be created between government authorities, the Natural Disaster Insurance Pool, private

  3. Abdominal Vascular Catastrophes.

    Science.gov (United States)

    Singh, Manpreet; Koyfman, Alex; Martinez, Joseph P

    2016-05-01

    Abdominal vascular catastrophes are among the most challenging and time sensitive for emergency practitioners to recognize. Mesenteric ischemia remains a highly lethal entity for which the history and physical examination can be misleading. Laboratory tests are often unhelpful, and appropriate imaging must be quickly obtained. A multidisciplinary approach is required to have a positive impact on mortality rates. Ruptured abdominal aortic aneurysm likewise may present in a cryptic fashion. A specific type of ruptured aneurysm, the aortoenteric fistula, often masquerades as the more common routine gastrointestinal bleed. The astute clinician recognizes that this is a more lethal variant of gastrointestinal hemorrhage. PMID:27133247

  4. Cosmic impacts, cosmic catastrophes. II

    Science.gov (United States)

    Chapman, Clark R.; Morrison, David

    1990-01-01

    The role of extraterrestrial impacts in shaping the earth's history is discussed, arguing that cosmic impacts represent just one example of a general shift in thinking that has made the idea of catastrophes respectable in science. The origins of this view are presented and current catastrophic theory is discussed in the context of modern debate on the geological formation of the earth. Various conflicting theories are reviewed and prominent participants in the ongoing scientific controversy concerning catastrophism are introduced.

  5. RPF101, a new capsaicin-like analogue, disrupts the microtubule network accompanied by arrest in the G2/M phase, inducing apoptosis and mitotic catastrophe in the MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Sá-Júnior, Paulo Luiz de [Laboratory of Genetics, Butantan Institute, Vital Brasil Avenue 1500, Postal Code: 05503-900, Sao Paulo (Brazil); Pasqualoto, Kerly Fernanda Mesquita [Biochemistry and Biophysical Laboratory, Butantan Institute, Vital Brasil Avenue 1500, Postal Code: 05503-900, Sao Paulo (Brazil); Ferreira, Adilson Kleber [Laboratory of Genetics, Butantan Institute, Vital Brasil Avenue 1500, Postal Code: 05503-900, Sao Paulo (Brazil); Tavares, Maurício Temotheo; Damião, Mariana Celestina Frojuello Costa Bernstorff [Department of Pharmacy, School of Pharmaceutical Sciences, University of Sao Paulo, Prof. Lineu Prestes Avenue, 580, Postal Code: 05508-000, Sao Paulo (Brazil); Azevedo, Ricardo Alexandre de [Biochemistry and Biophysical Laboratory, Butantan Institute, Vital Brasil Avenue 1500, Postal Code: 05503-900, Sao Paulo (Brazil); Câmara, Diana Aparecida Dias; Pereira, Alexandre; Madeiro de Souza, Dener [Laboratory of Genetics, Butantan Institute, Vital Brasil Avenue 1500, Postal Code: 05503-900, Sao Paulo (Brazil); Parise Filho, Roberto, E-mail: roberto.parise@usp.br [Department of Pharmacy, School of Pharmaceutical Sciences, University of Sao Paulo, Prof. Lineu Prestes Avenue, 580, Postal Code: 05508-000, Sao Paulo (Brazil)

    2013-02-01

    Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Capsaicin, which is the primary pungent compound in red peppers, was reported to selectively inhibit the growth of a variety tumor cell lines. Here, we report for the first time a novel synthetic capsaicin-like analogue, RPF101, which presents a high antitumor activity on MCF-7 cell line, inducing arrest of the cell cycle at the G2/M phase through a disruption of the microtubule network. Furthermore, it causes cellular morphologic changes characteristic of apoptosis and a decrease of Δψm. Molecular modeling studies corroborated the biological findings and suggested that RPF101, besides being a more reactive molecule towards its target, may also present a better pharmacokinetic profile than capsaicin. All these findings support the fact that RPF101 is a promising anticancer agent. -- Highlights: ► We report for the first time that RPF101 possesses anticancer properties. ► RPF101 induces apoptosis of human breast cancer cells. ► RPF 101 decreases mitochondrial potential and induces DNA fragmentation.

  6. RPF101, a new capsaicin-like analogue, disrupts the microtubule network accompanied by arrest in the G2/M phase, inducing apoptosis and mitotic catastrophe in the MCF-7 breast cancer cells

    International Nuclear Information System (INIS)

    Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Capsaicin, which is the primary pungent compound in red peppers, was reported to selectively inhibit the growth of a variety tumor cell lines. Here, we report for the first time a novel synthetic capsaicin-like analogue, RPF101, which presents a high antitumor activity on MCF-7 cell line, inducing arrest of the cell cycle at the G2/M phase through a disruption of the microtubule network. Furthermore, it causes cellular morphologic changes characteristic of apoptosis and a decrease of Δψm. Molecular modeling studies corroborated the biological findings and suggested that RPF101, besides being a more reactive molecule towards its target, may also present a better pharmacokinetic profile than capsaicin. All these findings support the fact that RPF101 is a promising anticancer agent. -- Highlights: ► We report for the first time that RPF101 possesses anticancer properties. ► RPF101 induces apoptosis of human breast cancer cells. ► RPF 101 decreases mitochondrial potential and induces DNA fragmentation.

  7. Presidential Address: Catastrophe Theory and Catastrophes in China's Civil Service Examinations (Part 1).

    Science.gov (United States)

    D'Costa, Ayres

    1991-01-01

    Introduces Rene Thom's catastrophe theory, which is based upon complex theorems in multidimensional geometry. Catastrophe theory analysis begins by identifying the occurrence of major discontinuities, or catastrophes, in a system such as civil service exams, resulting in catastrophic change. (KS)

  8. Volcanoes and global catastrophes

    Science.gov (United States)

    Simkin, Tom

    1988-01-01

    The search for a single explanation for global mass extinctions has let to polarization and the controversies that are often fueled by widespread media attention. The historic record shows a roughly linear log-log relation between the frequency of explosive volcanic eruptions and the volume of their products. Eruptions such as Mt. St. Helens 1980 produce on the order of 1 cu km of tephra, destroying life over areas in the 10 to 100 sq km range, and take place, on the average, once or twice a decade. Eruptions producing 10 cu km take place several times a century and, like Krakatau 1883, destroy life over 100 to 1000 sq km areas while producing clear global atmospheric effects. Eruptions producting 10,000 cu km are known from the Quaternary record, and extrapolation from the historic record suggests that they occur perhaps once in 20,000 years, but none has occurred in historic time and little is known of their biologic effects. Even larger eruptions must also exist in the geologic record, but documentation of their volume becomes increasingly difficult as their age increases. The conclusion is inescapable that prehistoric eruptions have produced catastrophes on a global scale: only the magnitude of the associated mortality is in question. Differentiation of large magma chambers is on a time scale of thousands to millions of years, and explosive volcanoes are clearly concentrated in narrow belts near converging plate margins. Volcanism cannot be dismissed as a producer of global catastrophes. Its role in major extinctions is likely to be at least contributory and may well be large. More attention should be paid to global effects of the many huge eruptions in the geologic record that dwarf those known in historic time.

  9. Numerical simulations of collisional disruption of rotating gravitational aggregates: Dependence on material properties

    Science.gov (United States)

    Ballouz, R.-L.; Richardson, D. C.; Michel, P.; Schwartz, S. R.; Yu, Y.

    2015-03-01

    Our knowledge of the strengths of small bodies in the Solar System is limited by our poor understanding of their internal structures, and this, in turn, clouds our understanding of the formation and evolution of these bodies. Observations of the rotational states of asteroids whose diameters are larger than a few hundreds of meters have revealed that they are dominated by gravity and that most are unlikely to be monoliths; however, there is a wide range of plausible internal structures. Numerical and analytical studies of shape and spin limits of gravitational aggregates and their collisional evolution show a strong dependence on shear strength. In order to study this effect, we carry out a systematic exploration of the dependence of collision outcomes on dissipation and friction parameters of the material components making up the bodies. We simulate the catastrophic disruption (leading to the largest remnant retaining 50% of the original mass) of km-size asteroids modeled as gravitational aggregates using pkdgrav, a cosmology N-body code adapted to collisional problems and recently enhanced with a new soft-sphere collision algorithm that includes more realistic contact forces. We find that for a range of three different materials, higher friction and dissipation values increase the catastrophic disruption threshold by about half a magnitude. Furthermore, we find that pre-impact rotation systematically increases mass loss on average, regardless of the target's internal configuration. Our results have important implications for the efficiency of planet formation via planetesimal growth, and also more generally to estimate the impact energy threshold for catastrophic disruption, as this generally has only been evaluated for non-spinning bodies without detailed consideration of material properties.

  10. Catastrophic antiphospholipid Syndrome

    International Nuclear Information System (INIS)

    The antiphospholipid syndrome (APS) is characterized by venous, arterial thrombosis and miscarriages along with lupic anticoagulant and antibodies against anticardiolipin. The catastrophic antiphospholipid syndrome (CAPS) has been described since 1992 like a multiple organic dysfunction caused by multiple vascular thrombosis in three or more organs. The patients who suffer from this syndrome may have or not history of APS. There are two or three mechanisms that may cause the CAPS, alone or in combination: These are: 1. The multisystemic thrombotic disease with emphasis in microvasculature occlusion of the organs and occlusion of big arterial or veins 2. The disseminated intravascular coagulation (DIC) superimpose in 15% to 50% of the patients that, of course, conducted to an occlusive disease of arterioles, veins or capillaries. 3. A systemic inflammatory response syndrome (SIRS) induced by citoquines. In this review it is described clinical and laboratory features, pathogenesis and treatment of CAPS. For this purpose, it was searched for Medline from 1993 to 2000 and revised the most significant issues obtained by this medium

  11. Strategic reasoning and bargaining in catastrophic climate change games

    Science.gov (United States)

    Verendel, Vilhelm; Johansson, Daniel J. A.; Lindgren, Kristian

    2016-03-01

    Two decades of international negotiations show that agreeing on emission levels for climate change mitigation is a hard challenge. However, if early warning signals were to show an upcoming tipping point with catastrophic damage, theory and experiments suggest this could simplify collective action to reduce greenhouse gas emissions. At the actual threshold, no country would have a free-ride incentive to increase emissions over the tipping point, but it remains for countries to negotiate their emission levels to reach these agreements. We model agents bargaining for emission levels using strategic reasoning to predict emission bids by others and ask how this affects the possibility of reaching agreements that avoid catastrophic damage. It is known that policy elites often use a higher degree of strategic reasoning, and in our model this increases the risk for climate catastrophe. Moreover, some forms of higher strategic reasoning make agreements to reduce greenhouse gases unstable. We use empirically informed levels of strategic reasoning when simulating the model.

  12. Death, Catastrophe, and the Significance of Tragedy

    Directory of Open Access Journals (Sweden)

    Jennifer Ballengee

    2014-05-01

    Full Text Available This NANO note will examine the tension between representation, memorial, and the catastrophe of death that emerges in the space of tragedy, as the problem arises in two quite different works: Oedipus at Colonus, a fairly typical fifth-century Greek tragedy, and Falling Man, Don DeLillo’s novel that, in its attempt to address the events of 9/11, reflects in form and subject matter many of Aristotle’s terms of tragic representation. It is not the intent of this note to engage with the recent proliferation of work in “performance theory.” Rather than being concerned with an imagined exchange between audience and actor, this study examines how the supplementary relationship of gesture and speech in tragedy disrupts the public/private distinction, and how this articulation effects and enables the public memorialization of death. Thus, this paper will consider the representation of death as an event whose catastrophic, and somewhat mysterious, collision of the public and the private lends it its tragic significance.

  13. Should Governments Provide Catastrophe Insurance?

    OpenAIRE

    Jaffee, Dwight; Russell, Thomas

    2005-01-01

    Hurricane Katrina and the terrorist attacks of 9/11 2001 have focused attention on the appropriate role of government in providing insurance against catastrophes. This paper argues that wherever possible governments should follow policies which enable the continuation of a private insurance market. In the event that government must itself provide catastrophe insurance it should follow the same actuarially based pricing and reserving rules that would be followed by a competitive private market.

  14. SPH calculations of asteroid disruptions: The role of pressure dependent failure models

    CERN Document Server

    Jutzi, Martin

    2015-01-01

    We present recent improvements of the modeling of the disruption of strength dominated bodies using the Smooth Particle Hydrodynamics (SPH) technique. The improvements include an updated strength model and a friction model, which are successfully tested by a comparison with laboratory experiments. In the modeling of catastrophic disruptions of asteroids, a comparison between old and new strength models shows no significant deviation in the case of targets which are initially non-porous, fully intact and have a homogeneous structure (such as the targets used in the study by Benz&Asphaug (1999). However, for many cases (e.g. initially partly or fully damaged targets, rubble-pile structures, etc.) we find that it is crucial that friction is taken into account and the material has a pressure dependent shear strength. Our investigations of the catastrophic disruption threshold $Q^*_{D}$ as a function of target properties and target sizes up to a few 100 km show that a fully damaged target modeled without frict...

  15. Women, catastrophe and mental health.

    Science.gov (United States)

    Raphael, Beverley; Taylor, Mel; McAndrew, Virginia

    2008-01-01

    This paper examines the concept of catastrophic experience, its relationship to the range of acute and prolonged stressors to which women may be exposed and the broad impacts on their mental health and well-being. It identifies catastrophe in terms of multiple accumulated stresses including death, loss, victimization, demoralization, shame, stigmatization, helplessness and identity. Catastrophic experiences include personal violence in domestic circumstances of intimate partner abuse, sexual assault and child physical and sexual abuse. Women's experiences of loss through the violent deaths of children and loved ones may also have such enduring impacts. Terrorism victimizes men and women in this way, with the enduring impacts for women in terms of threat of ongoing attacks as well as acute effects and their aftermath. The catastrophes of war, conflict, genocide, sexual exploitation and refugee status differentially affect large numbers of women, directly and through their concerns for the care of their children and loved ones. Ultimate catastrophes such as Hiroshima and the Holocaust are discussed but with recognition of the very large numbers of women currently experiencing catastrophe in ongoing ways that may be silent and unrecognized. This is significant for clinical care and population impacts, and in the losses for women across such contexts. PMID:18058439

  16. The Ongoing Catastrophe

    DEFF Research Database (Denmark)

    Kublitz, Anja

    . Shrouded in smoke from cigarettes and argilas (water pipes), the women would sing along to the latest Lebanese pop songs, dance and try on different outfits while they commented on each other bottoms, breasts and complexions and exchanged views on men, underwear and creams. These regular occasions of......Based on sixteen months of fieldwork among Palestinians living in housing projects in Denmark this paper examines how girl talk offer a transformative threshold that allow Palestinian women to become someone else, if only for a moment. The history of the Palestinian women that forms the tapestry...... abusive husbands. The plenitude of suffering, however, is only seldom discussed in public. What is discussed in detail is for instance g-strings, boob jobs and facial creams. My first impression of the different women’s clubs in the basement of projects in Denmark was an overwhelming sensory experience...

  17. Sudden stratospheric warmings as catastrophes

    Science.gov (United States)

    Chao, W. C.

    1985-01-01

    The sudden stratospheric warming (SSW) process is qualitatively studied using a conceptual and numerical approach guided by catastrophe theory. A simple example of a catastrophe taken from nonlinear dynamics is given, and results from previous modelling studies of SSW are interpreted in light of catastrophe theory. Properties of this theory such as hysteresis, cusp, and triggering essential to SSW are numerically demonstrated using the truncated quasi-geostrophic beta-plane model of Holton and Mass (1976). A qualitative explanation of the transition from the steady regime to the vacillation regime is given for the Holton and Mass model in terms of the topographically induced barotropic Rossby wave instability. Some implications for the simulation and prediction of SSW are discussed.

  18. Modelling catastrophic risk in international equity markets: An extreme value approach

    OpenAIRE

    Cotter, John

    2011-01-01

    This letter uses the Block Maxima Extreme Value approach to quantify catastrophic risk in international equity markets. Risk measures are generated from a set threshold of the distribution of returns that avoids the pitfall of using absolute returns for markets exhibiting diverging levels of risk. From an application to leading markets, the letter finds that the Nikkei is more prone to catastrophic risk than the FTSE and Dow Jones Indexes.

  19. The Climate Catastrophe as Blockbuster

    DEFF Research Database (Denmark)

    Eskjær, Mikkel Fugl

    2013-01-01

    Modern disaster films constitute a specific cultural form that speaks to the anxieties of the “risk society.” This essay looks at how risks like climate change is presented and constructed in popular culture. It regards blockbuster representations as part of a wider discourse of “catastrophism...

  20. Constructive criterion of catastrophe inevitability

    International Nuclear Information System (INIS)

    A mathematical procedure is proposed for the constructive criteria of nuclear catastrophe inevitability. It was concluded that the procedure can fulfill the objective set, and it allows to make a full formal safety classification of object states. (N.T.). 1 ref., 1 fig

  1. Severe catastrophes and public reactions

    International Nuclear Information System (INIS)

    nuclear opposition. Economical basis of nuclear energy stagnation is in not very successful competition of nuclear engineering with fossil energy production technologies. Much money has been spent for improvement of safety of NPPs. Social roots of the opposition are linked with a bad experience of the public with demonstration of the nuclear energy- The explosion of atomic bombs, some contamination of the territories after nuclear arm tests, misfortunes with TMI-2 and Chernobyl have created a stable enmity and non-acceptance of the all connected with 'atom'. The mass media have strongly promoted the dissemination of the fear of radiation exposures. There is also an influence on that attitude the radiation protection regulation via the declaration of the linear no-threshold dependence of the radiation detriments and dose of exposure. Such concept ignores the adoptive features of all living. But modem studies have showed that protracted irradiation at the same dose is much less dangerous compared with sharp one. It could change public attitude to nuclear energy in the society. Role of nuclear communication for public informing: The reactions of public on various technological and man-made events differ significantly and are being determined not scales of catastrophes but the mental impression and a multiplication of psychological stresses in the society by mass -media. In present situation a nuclear community has to improve the contacts with the pubic, to launch more effective campaign for explanation of real adventures of nuclear power. It needs to compare the risks of climate warming and health detriments from different electricity production technologies and to show that nuclear power is a single alternative all fossil burning techniques of electricity production. It's the truth the nuclear power is a real method of fight for suppression of emission the greenhouse gases, isn't it? (author)

  2. Madame Bovary and Catastrophism: Revolving narratives

    Directory of Open Access Journals (Sweden)

    Ruth Morris

    2011-07-01

    Bovary within the scientific milieu of 1850s French society by reading Flaubert’s narrative as a Cuverian text. The French scientist Georges Cuvier, along with many of his contemporaries, formulated the catastrophist theory as a means of explaining the origins of the world. In catastrophism, the world is divided into very discrete time periods which are punctuated by vast catastrophes, or in Cuverian terminology ‘revolutions’ that have eradicated life and enabled the world to be repopulated afresh. This has implications for the concept of ‘time’. Cuvier theorises the earth as being relatively recent in origin, with the present epoch being only five thousand years old. This compression of time can be inferred in Madame Bovary through references to rapidity and the tempo which increases towards the denouement. In catastrophism and Madame Bovary, time is not constructed in a linear or chronological manner. The ‘revolutions’ disrupt a realisation of continuous time and Emma is frequently unable to distinguish between past, present and future experiences. The ‘revolutions’ also serve to puncture and disrupt the status quo of life by creating massive events within the earth’s history. Emma’s life too parallels this. She regards her existence as being informed by magnitudinous events, such as the ball, which creates dislocated and fragmented time as in Cuviers’ theory. I will also argue for a connection between the suddenness and violence of the ‘revolutions’ and Emma Bovary’s emotional outbursts which occur without for-warning and border on the hysterical. A Cuverian concept of time has implications for other considerations which are arguably the main differences between catastrophism and evolution theory. These include the notions of adaptation, inheritance and death within Flaubert’s narrative.

  3. Catastrophic events and older adults.

    Science.gov (United States)

    Cloyd, Elizabeth; Dyer, Carmel B

    2010-12-01

    The plight of older adults during catastrophic events is a societal concern. Older persons have an increased prevalence of cognitive disorders, chronic illnesses, and mobility problems that limit their ability to cope. These disorders may result in a lack of mental capacity and the ability to discern when they should evacuate or resolve problems encountered during a catastrophe. Some older persons may have limited transportation options, and many of the elderly survivors are at increased risk for abuse, neglect, and exploitation. Recommendations for future catastrophic events include the development of a federal tracking system for elders and other vulnerable adults, the designation of separate shelter areas for elders and other vulnerable adults, and involvement of gerontological professionals in all aspects of emergency preparedness and care delivery, including training of frontline workers. Preparation through preevent planning that includes region-specific social services, medical and public health resources, volunteers, and facilities for elders and vulnerable adults is critical. Elders need to be protected from abuse and fraud during catastrophic events. A public health triage system for elders and other vulnerable populations in pre- and postdisaster situations is useful, and disaster preparedness is paramount. Communities and members of safety and rescue teams must address ethical issues before an event. When older adults are involved, consideration needs to be given to triage decision making, transporting those who are immobile, the care of older adults who receive palliative care, and the equitable distribution of resources. Nurses are perfectly equipped with the skills, knowledge, and training needed to plan and implement disaster preparedness programs. In keeping with the tradition of Florence Nightingale, nurses can assume several crucial roles in disaster preparedness for older adults. Nurses possess the ability to participate and lead community

  4. Disrupting Vestibular Activity Disrupts Body Ownership.

    Science.gov (United States)

    Hoover, Adria E N; Harris, Laurence R

    2015-01-01

    People are more sensitive at detecting asynchrony between a self-generated movement and visual feedback concerning that movement when the movement is viewed from a first-person perspective. We call this the 'self-advantage' and interpret it as an objective measure of self. Here we ask if disruption of the vestibular system in healthy individuals affects the self-advantage. Participants performed finger movements while viewing their hand in a first-person ('self') or third-person ('other') perspective and indicated which of two periods (one with minimum delay and the other with an added delay of 33-264 ms) was delayed. Their sensitivity to the delay was calculated from the psychometric functions obtained. During the testing, disruptive galvanic vestibular stimulation (GVS) was applied in five-minute blocks interleaved with five minutes of no stimulation for a total of 40 min. We confirmed the self-advantage under no stimulation (31 ms). In the presence of disruptive GVS this advantage disappeared and there was no longer a difference in performance between perspectives. The threshold delay for the 'other' perspective was not affected by the GVS. These results suggest that an intact vestibular signal is required to distinguish 'self' from 'other' and to maintain a sense of body ownership. PMID:26595957

  5. Is Geothermal Simulation a "Catastrophe"?

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, V.V.; Pinder, George F.

    1980-12-16

    All numerical simulators of geothermal reservoirs depend upon an accurate representation of the thermodynamics of steam-water systems. These relationships are required to render tractable the system of balance equations derived from the physics of flow through porous media. While it is generally recognized that the steam-water system (i.e. two phase) is not in thermodynamic equilibrium, equihbrium thermodynamics are employed in its description. In this paper, we present an alternative view based on non-equilibrium thermodynamics. The underpinnings of this approach are found in a branch of topology generally referred to as "catastrophe theory". [Thom, 1975

  6. Is geothermal simulation a catastrophe

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, V.V.; Pinder, G.F.

    1980-01-01

    All numerical simulators of geothermal reservoirs depend upon an accurate representation of the thermodynamics of steam-water systems. These relationships are required to render tractable the system of balance equations derived from the physics of flow through porous media. While it is generally recognized that the steam-water system (i.e., two phase) is not in thermodynamic equilibrium, equilibrium thermodynamics are employed in its description. An alternative view based on non-equilibrium thermodynamics is presented. The underpinnings of this approach are found in a branch of topology generally referred to as catastrophe theory.

  7. A catastrophe in quantum mechanics

    International Nuclear Information System (INIS)

    The standard scattering theory (SST) in nonrelativistic quantum mechanics (QM) is analyzed. Self-contradictions of SST are deconstructed. A direct way to calculate scattering probability without introduction of a finite volume is discussed. Substantiation of SST in textbooks with the help of wave packets is shown to be incomplete. A complete theory of wave packet scattering on a fixed center is presented, and its similarity to the plane wave scattering is demonstrated. The neutron scattering on a monatomic gas is investigated, and several problems are pointed out. A catastrophic ambiguity of the cross section is revealed, and a way to resolve this ambiguity is discussed

  8. The Diseconomies of Environmental Catastrophes

    OpenAIRE

    Cairns, John

    2006-01-01

    Four factors are almost certain to lead to one or more catastrophes unless major remedial measures are taken. (1) China has replaced the United States as the world s leading consumer of resources, except for oil (Brown, 2006a), but China is already a major factor in the world market in this area also. Together, China and the United States consume approximately half the world s resources and the global population is still increasing on a finite planet. (2) The over 20% global ecological oversh...

  9. Catastrophic models of materials destruction

    Science.gov (United States)

    Kupchishin, A. I.; Taipova, B. G.; Kupchishin, A. A.; Voronova, N. A.; Kirdyashkin, V. I.; Fursa, T. V.

    2016-02-01

    The effect of concentration and type of fillers on mechanical properties of composite material based on polyimide were studied. Polyethylene terephthalate (PET, polyester), polycarbonate (PCAR) and montmorillonite (MM) were used as the fillers. The samples were prepared by mechanically blending the polyimide-based lacquer solutions with different concentrations of the second component. The concentration of filler and its class, especially their internal structure and technology of synthesis determine features of physical and mechanical properties of obtained materials. Models of catastrophic failure of material satisfactorily describe the main features depending on tension ct from deformation e.

  10. Family Disruptions

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Life Listen Español Text Size Email Print Share Family Disruptions Page Content Article Body No matter how ...

  11. Extensional rheometer based on viscoelastic catastrophes outline

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a method and a device for determining viscoelastic properties of a fluid. The invention resides inter alia in the generation of viscoelastic catastrophes in confined systems for use in the context of extensional rheology. The viscoelastic catastrophe is according to...... the invention generated in a bistable fluid system, and the flow conditions for which the catastrophe occurs can be used as a fingerprint of the fluid's viscoelastic properties in extensional flow....

  12. Effects of microtubule mechanics on hydrolysis and catastrophes

    International Nuclear Information System (INIS)

    We introduce a model for microtubule (MT) mechanics containing lateral bonds between dimers in neighboring protofilaments, bending rigidity of dimers, and repulsive interactions between protofilaments modeling steric constraints to investigate the influence of mechanical forces on hydrolysis and catastrophes. We use the allosteric dimer model, where tubulin dimers are characterized by an equilibrium bending angle, which changes from 0∘ to 22∘ by hydrolysis of a dimer. This also affects the lateral interaction and bending energies and, thus, the mechanical equilibrium state of the MT. As hydrolysis gives rise to conformational changes in dimers, mechanical forces also influence the hydrolysis rates by mechanical energy changes modulating the hydrolysis rate. The interaction via the MT mechanics then gives rise to correlation effects in the hydrolysis dynamics, which have not been taken into account before. Assuming a dominant influence of mechanical energies on hydrolysis rates, we investigate the most probable hydrolysis pathways both for vectorial and random hydrolysis. Investigating the stability with respect to lateral bond rupture, we identify initiation configurations for catastrophes along the hydrolysis pathways and values for a lateral bond rupture force. If we allow for rupturing of lateral bonds between dimers in neighboring protofilaments above this threshold force, our model exhibits avalanche-like catastrophe events. (papers)

  13. Catastrophe mechanism & classification of discontinuity behavior in thermal science (Ⅰ) --Fold catastrophe

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The mechanism of discontinuity behavior has important significance in the study of thermal science,such as fire,combustion,explosion and heat transfer.This sort of discontinuity behavior and the catastrophe caused by system nonlinearity may be equivalently classified according to the catastrophe model promulgated by catastrophe theory.Under the conditions of uniform temperature and thermal isolation,the self-ignition behavior of a Semenov System can be viewed as a result of the fold catastrophe of the system.

  14. Academic Training: Predicting Natural Catastrophes

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 12, 13, 14, 15, 16 December from 11:00 to 12:00 - Main Auditorium, bldg. 500 Predicting Natural Catastrophes E. OKAL / Northwestern University, Evanston, USA 1. Tsunamis -- Introduction Definition of phenomenon - basic properties of the waves Propagation and dispersion Interaction with coasts - Geological and societal effects Origin of tsunamis - natural sources Scientific activities in connection with tsunamis. Ideas about simulations 2. Tsunami generation The earthquake source - conventional theory The earthquake source - normal mode theory The landslide source Near-field observation - The Plafker index Far-field observation - Directivity 3. Tsunami warning General ideas - History of efforts Mantle magnitudes and TREMOR algorithms The challenge of 'tsunami earthquakes' Energy-moment ratios and slow earthquakes Implementation and the components of warning centers 4. Tsunami surveys Principles and methodologies Fifteen years of field surveys and re...

  15. Catastrophe Finance: An Emerging Discipline

    Science.gov (United States)

    Elsner, James B.; Burch, R. King; Jagger, Thomas H.

    2009-08-01

    While the recent disasters in the world's financial markets demonstrate that finance theory remains far from perfected, science also faces steep challenges in the quest to predict and manage the effects of natural disasters. Worldwide, as many as half a million people have died in disasters such as earthquakes, tsunamis, and tropical cyclones since the turn of the 21st century [Wirtz, 2008]. Further, natural disasters can lead to extreme financial losses, and independent financial collapses can be exacerbated by natural disasters. In financial cost, 2008 was the second most expensive year on record for such catastrophes and for financial market declines. These extreme events in the natural and financial realms push the issue of risk management to the fore, expose the deficiencies of existing knowledge and practice, and suggest that progress requires further research and training at the graduate level.

  16. Climate Catastrophe - The Giant Swindle

    International Nuclear Information System (INIS)

    Energy is the life-blood of civilization. More than 80% of global energy is supplied by fossil fuels. And this will continue for the foreseeable future - if an implementation of the Kyoto Protocol does not lead to a dramatic decrease of these fuels causing worldwide turmoil of unprecedented dimensions. However, the scaremongering with a 'climate catastrophe' allegedly caused by 'greenhouse gas' emissions from the burning of fossil fuels is a huge hoax. Its only 'scientific' base is the IPCC management's enigmatic assessment: 'The balance of evidence suggests a discernable human influence on climate'. But even IPCC had to admit at the World Energy Conference in Tokyo in 1996: 'We have no evidence'. And all the scaremongering assertions of the protagonists of 'global warming' have been convincingly refuted by the world elite of scientists. This paper will: - show how the whole anti-CO2 campaign has been manipulated from the very beginning till today; - give great many scientific and logical reason why the arguments of the scaremongers are incorrect; - outline the catastrophic economic and social consequences of the proposed anti-CO2 measures - without any benefit for the environment of climate; - name the driving forces behind this campaign and their interests. The witchhunt against CO2 is an incredible scientific and political scandal, CO2 does not damage the environment at all, and labelling it a 'climate killer' is absurd. On the contrary, this gas is vital for the life on our plant, and a stronger concentration of CO2 will be beneficial by doubling plant growth and with this combatting global famine. And to pretend that we could influence - with a CO2 tax - the climate, is insane arrogance. Man is absolutely helpless when confronted with the forces of nature. The squandering of multimillions USD of taxpayer's money for the travelling circus of 'Climate summits' and the stultification of the population must stop. The 'global warming' lie is the biggest

  17. Catastrophe theory with application in nuclear technology

    International Nuclear Information System (INIS)

    The monograph is structured on the following seven chapters: 1. Correlation of risk, catastrophe and chaos at the level of polyfunctional systems with nuclear injection; 1.1 Approaching the risk at the level of power systems; 1.2 Modelling the chaos-catastrophe-risk correlation in the structure of integrated classical and nuclear processes; 2. Catastrophe theory applied in ecosystems models and applications; 2.1 Posing the problems in catastrophe theory; 2.2 Application of catastrophe theory in the engineering of the power ecosystems with nuclear injection; 4.. Decision of abatement of the catastrophic risk based on minimal costs; 4.1 The nuclear power systems sensitive to risk-catastrophe-chaos in the structure of minimal costs; 4.2 Evaluating the market structure on the basis of power minimal costs; 4.3 Decisions in power systems built on minimal costs; 5. Models of computing the minimal costs in classical and nuclear power systems; 5.1 Calculation methodologies of power minimal cost; 5.2 Calculation methods of minimal costs in nuclear power sector; 6. Expert and neuro expert systems for supervising the risk-catastrophe-chaos correlation; 6.1 The structure of expert systems; 6.2 Application of the neuro expert program; 7. Conclusions and operational proposals; 7.1 A synthesis of the problems presented in this work; 7.2 Highlighting the novel aspects applicable in the power systems with nuclear injection

  18. Adaptation to and Recovery from Global Catastrophe

    Directory of Open Access Journals (Sweden)

    Seth D. Baum

    2013-03-01

    Full Text Available Global catastrophes, such as nuclear war, pandemics and ecological collapse threaten the sustainability of human civilization. To date, most work on global catastrophes has focused on preventing the catastrophes, neglecting what happens to any catastrophe survivors. To address this gap in the literature, this paper discusses adaptation to and recovery from global catastrophe. The paper begins by discussing the importance of global catastrophe adaptation and recovery, noting that successful adaptation/recovery could have value on even astronomical scales. The paper then discusses how the adaptation/recovery could proceed and makes connections to several lines of research. Research on resilience theory is considered in detail and used to develop a new method for analyzing the environmental and social stressors that global catastrophe survivors would face. This method can help identify options for increasing survivor resilience and promoting successful adaptation and recovery. A key point is that survivors may exist in small isolated communities disconnected from global trade and, thus, must be able to survive and rebuild on their own. Understanding the conditions facing isolated survivors can help promote successful adaptation and recovery. That said, the processes of global catastrophe adaptation and recovery are highly complex and uncertain; further research would be of great value.

  19. Fracto—emissions in Catastrophic Cleavage Process

    Institute of Scientific and Technical Information of China (English)

    HonglaiTAN; WeiYANG

    1996-01-01

    Fracto-emissions accompanying crack propagation are observed in the recent experiments.The energy impulses during and after fracture stimulate the fracto-emissions.Model concerning atomic scale cleavage processes is proposed to formulate a catastrophic fracure theory relevant to these phenomena.A criterion for catastrophic jump of the cleavage potential is applied to representative crystals.

  20. 76 FR 50929 - Catastrophic Risk Protection Endorsement

    Science.gov (United States)

    2011-08-17

    ..., published at 48 FR 29115, June 24, 1983. Executive Order 12988 This proposed rule has been reviewed in...; ] DEPARTMENT OF AGRICULTURE Federal Crop Insurance Corporation 7 CFR Part 402 RIN 0563-AC31 Catastrophic Risk... Federal Crop Insurance Corporation (FCIC) proposes to amend the Catastrophic Risk Protection...

  1. Environmental Catastrophes Under Time-inconsistent Preferences

    NARCIS (Netherlands)

    Michielsen, T.O.

    2013-01-01

    Abstract I analyze optimal natural resource use in an intergenerational model with the risk of a catastrophe. Each generation maximizes a weighted sum of discounted utility (positive) and the probability that a catastrophe will occur at any point in the future (negative). The model generates time-in

  2. Disrupting Business

    DEFF Research Database (Denmark)

    Cox, Geoff; Bazzichelli, Tatiana

    Disruptive Business explores some of the interconnections between art, activism and the business concept of disruptive innovation. With a backdrop of the crisis of financial capitalism, austerity cuts in the cultural sphere, the idea is to focus on potential art strategies in relation to a broken...... economy. In a perverse way, we ask whether this presents new opportunities for cultural producers to achieve more autonomy over their production process. If it is indeed possible, or desirable, what alternative business models emerge? The book is concerned broadly with business as material for reinvention...

  3. Catastrophe mechanism and classification of discontinuity behavior in thermal science (Ⅱ) -- Cusp catastrophe

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The catastrophe mechanisms of thermal performance characteristics of the firebox gas combustion system were analyzed from the viewpoint of catastrophe theory. The mathematical models of cusp catastrophe were established. The relationship between the thermal performance characteristics and the changing of system control variables was studied. The cusp catastrophe mechanisms of typical performance characteristics, such as kicking and lagging, and those of transition from quenching to igniting were explained. It was illustrated that discontinuity behavior of thermal systems with an "S" motion feature curve and lagging feature may be equivalently classified according to the topology of cusp catastrophe, influenced by two groups of independent control variables.

  4. Quantum catastrophes: a case study

    Science.gov (United States)

    Znojil, Miloslav

    2012-11-01

    The bound-state spectrum of a Hamiltonian H is assumed real in a non-empty domain D of physical values of parameters. This means that for these parameters, H may be called crypto-Hermitian, i.e. made Hermitian via an ad hoc choice of the inner product in the physical Hilbert space of quantum bound states (i.e. via an ad hoc construction of the operator Θ called the metric). The name quantum catastrophe is then assigned to the N-tuple-exceptional-point crossing, i.e. to the scenario in which we leave the domain D along such a path that at the boundary of D, an N-plet of bound-state energies degenerates and, subsequently, complexifies. At any fixed N ⩾ 2, this process is simulated via an N × N benchmark effective matrix Hamiltonian H. It is being assigned such a closed-form metric which is made unique via an N-extrapolation-friendliness requirement. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Quantum physics with non-Hermitian operators’.

  5. Quantum catastrophes: a case study

    International Nuclear Information System (INIS)

    The bound-state spectrum of a Hamiltonian H is assumed real in a non-empty domain D of physical values of parameters. This means that for these parameters, H may be called crypto-Hermitian, i.e. made Hermitian via an ad hoc choice of the inner product in the physical Hilbert space of quantum bound states (i.e. via an ad hoc construction of the operator Θ called the metric). The name quantum catastrophe is then assigned to the N-tuple-exceptional-point crossing, i.e. to the scenario in which we leave the domain D along such a path that at the boundary of D, an N-plet of bound-state energies degenerates and, subsequently, complexifies. At any fixed N ⩾ 2, this process is simulated via an N × N benchmark effective matrix Hamiltonian H. It is being assigned such a closed-form metric which is made unique via an N-extrapolation-friendliness requirement. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Quantum physics with non-Hermitian operators’. (paper)

  6. A story of transformation following catastrophic loss.

    Science.gov (United States)

    Rateau, Margaret R

    2010-08-01

    The emotional impact following catastrophic loss is a highly individualized and personal experience. Such an experience may be life transforming and can significantly influence the course of one's emotional recovery. Through the gathering of story, a clearer understanding of the transformational experience may lead to more appropriate mental health support for those most in need. The purposes of this article are to share the author's 4-year autobiographical story following catastrophic loss from a house explosion and fire, to discuss the transpersonal perspective on transformation, and to offer the use of story for practice and research applications for persons experiencing catastrophic loss. PMID:20650371

  7. Disrupted Disclosure

    DEFF Research Database (Denmark)

    Krause Hansen, Hans; Uldam, Julie

    While projects of governance by transparency have become widespread over the past decades, theyare usually investigated and theorized in isolation from the wider field of visibility and surveillancein which they are embedded. Building on theories of governance, visibility and surveillance...... appearances become challenged through disruptive disclosures in mediaenvironments characterized by multiple levels of visibility, with companies both observing andbeing observed by civil society groups that criticize them; (c) why and how the mobilization aroundtransparency and ensuing practices...

  8. CATASTROPHIC ECO-ENVIRONMENTAL CHANGE IN THE SONGNEN PLAIN, NORTHEASTERN CHINA SINCE 1900S

    Institute of Scientific and Technical Information of China (English)

    WANG Hai-xia; WAN Zhong-juan; YU Shao-peng; LUO Xin-zheng; SUN Guang-you

    2004-01-01

    Although the Songnen Plain in the northeastern China was developed relatively late in the temperate zone of the world, its eco-environment has changed greatly. This paper analyzes the changes of land cover and the rates and trends ofdesertification during the past 100 years in the Songnen Plain. According to the macroscopic analysis, we find that the eco-environment in the plain has reached to the threshold of catastrophic change since the 1950s. The Thom Needle Catastrophic Model was used to determine and validate this conclusion. Human activities, including large-scale construction projects, such as huge dams and dikes, and excessive grazing were the primary factors contributing to regional eco-environmental catastrophe. And irrational reclamation of the wilderness also affected the eco-environmental change. The results reveal the complex human-land interactions.

  9. Insuring catastrophes and the role of governments

    Science.gov (United States)

    Boyer, M. M.; Nyce, C. M.

    2013-08-01

    In this paper we model the cost of providing insurance coverage against natural and man-made hazards. We propose an insurance market model that explains (1) the use of reinsurance to help finance the cost of catastrophic events and (2) the implicit (or explicit) presence of government entities acting as (re)insurers of last resort. Using an economic model, we show how insurance programmes should be designed to cover the losses due to a possible catastrophic natural hazard. Our results show that the optimal structure of a reinsurance programme minimizes the cost of offering insurance protection. We also show how government intervention can reduce the cost of insurance against natural catastrophes and increase policyholders' welfare. Our paper therefore offers public policy implications as to the role and presence of government as an insurer of last resort and the minimum insurance premium necessary to cover the cost of catastrophic events.

  10. Catastrophes in Scale-Free Networks

    Institute of Scientific and Technical Information of China (English)

    ZHOU Tao; WANG Bing-Hong

    2005-01-01

    @@ An alternative model about cascading occurrences caused by perturbation is established to search the mechanism because catastrophes in networks occur. We investigate the avalanche dynamics of our model on two-dimensional Euclidean lattices and scale-free networks and find that the avalanche dynamic behaviour is sensitive to the topological structure of networks. The simulation results show that the catastrophes occur much more frequently in scale-free networks than those in Euclidean lattices, and the greatest catastrophe in scale-free networks is much more serious than that in Euclidean lattices. Furthermore, we have studied how to reduce the catastrophes'degree, and have schemed out an effective strategy, called the targeted safeguard strategy for scale-free networks.

  11. Catastrophic event modeling. [lithium thionyl chloride batteries

    Science.gov (United States)

    Frank, H. A.

    1981-01-01

    A mathematical model for the catastrophic failures (venting or explosion of the cell) in lithium thionyl chloride batteries is presented. The phenomenology of the various processes leading to cell failure is reviewed.

  12. Insuring catastrophes and the role of governments

    Directory of Open Access Journals (Sweden)

    M. M. Boyer

    2013-08-01

    Full Text Available In this paper we model the cost of providing insurance coverage against natural and man-made hazards. We propose an insurance market model that explains (1 the use of reinsurance to help finance the cost of catastrophic events and (2 the implicit (or explicit presence of government entities acting as (reinsurers of last resort. Using an economic model, we show how insurance programmes should be designed to cover the losses due to a possible catastrophic natural hazard. Our results show that the optimal structure of a reinsurance programme minimizes the cost of offering insurance protection. We also show how government intervention can reduce the cost of insurance against natural catastrophes and increase policyholders' welfare. Our paper therefore offers public policy implications as to the role and presence of government as an insurer of last resort and the minimum insurance premium necessary to cover the cost of catastrophic events.

  13. Microtubule dynamics: Caps, catastrophes, and coupled hydrolysis

    DEFF Research Database (Denmark)

    Flyvbjerg, H.; Holy, T.E.; Leibler, S.

    1996-01-01

    probability distributions relating to available experimental data are derived. Caps are found to be short and the total rate of hydrolysis at a microtubule end is found to be dynamically coupled to growth. The so-called catastrophe rate is a simple function of the microtubule growth rare and fits experimental...... data. A constant nonzero catastrophe rare, identical for both microtubule ends, is predicted at large growth rates. The delay time for dilution-induced catastrophes is stochastic with a simple distribution that fits the experimental one and, like the experimental one, does not depend on the rate of...... unified description of several apparently contradictory experimental data. Experimental results for the catastrophe rate at different concentrations of magnesium ions and of microtubule associated proteins are discussed in terms of the model. Feasible experiments are suggested that can provide decisive...

  14. Valuing Catastrophe Bonds Involving Credit Risks

    OpenAIRE

    Jian Liu; Jihong Xiao; Lizhao Yan; Fenghua Wen

    2014-01-01

    Catastrophe bonds are the most important products in catastrophe risk securitization market. For the operating mechanism, CAT bonds may have a credit risk, so in this paper we consider the influence of the credit risk on CAT bonds pricing that is different from the other literature. We employ the Jarrow and Turnbull method to model the credit risks and get access to the general pricing formula using the Extreme Value Theory. Furthermore, we present an empirical pricing study of the Property C...

  15. Catastrophic avalanches and methods of their control

    Directory of Open Access Journals (Sweden)

    N. A. Volodicheva

    2014-01-01

    Full Text Available Definition of such phenomenon as “catastrophic avalanche” is presented in this arti-cle. Several situations with releases of catastrophic avalanches in mountains of Caucasus, Alps, and Central Asia are investigated. Materials of snow-avalanche ob-servations performed since 1960s at the Elbrus station of the Lomonosov Moscow State University (Central Caucasus were used for this work. Complex-valued measures of engineering protection demonstrating different efficiencies are consid-ered.

  16. Mindfulness, Acceptance and Catastrophizing in Chronic Pain

    OpenAIRE

    de Boer, Maaike J.; Steinhagen, Hannemike E.; Versteegen, Gerbrig J.; Struys, Michel M.R.F.; Sanderman, Robbert

    2014-01-01

    Objectives: Catastrophizing is often the primary target of the cognitive-behavioral treatment of chronic pain. Recent literature on acceptance and commitment therapy (ACT) suggests an important role in the pain experience for the concepts mindfulness and acceptance. The aim of this study is to examine the influence of mindfulness and general psychological acceptance on pain-related catastrophizing in patients with chronic pain. Methods: A cross-sectional survey was conducted, including 87 chr...

  17. Catastrophizing and Causal Beliefs in Whiplash

    OpenAIRE

    Buitenhuis, J.; de Jong, P J; Jaspers, J. P. C.; Groothoff, J. W.

    2008-01-01

    Study Design. Prospective cohort study. Objective. This study investigates the role of pain catastrophizing and causal beliefs with regard to severity and persistence of neck complaints after motor vehicle accidents. Summary of Background Data. In previous research on low back pain, somatoform disorders and chronic fatigue syndrome, pain catastrophizing and causal beliefs were found to be related to perceived disability and prognosis. Furthermore, it has been argued with respect to whiplash t...

  18. The Economic and Policy Consequences of Catastrophes

    OpenAIRE

    Robert S. Pindyck; Neng Wang

    2013-01-01

    How likely is a catastrophic event that would substantially reduce the capital stock, GDP, and wealth? How much should society be willing to pay to reduce the probability or impact of a catastrophe? We answer these questions and provide a framework for policy analysis using a general equilibrium model of production, capital accumulation, and household preferences. Calibrating the model to economic and financial data, we estimate the mean arrival rate of shocks and their size distribution, the...

  19. Mindfulness, acceptance and catastrophizing in chronic pain.

    Directory of Open Access Journals (Sweden)

    Maaike J de Boer

    Full Text Available OBJECTIVES: Catastrophizing is often the primary target of the cognitive-behavioral treatment of chronic pain. Recent literature on acceptance and commitment therapy (ACT suggests an important role in the pain experience for the concepts mindfulness and acceptance. The aim of this study is to examine the influence of mindfulness and general psychological acceptance on pain-related catastrophizing in patients with chronic pain. METHODS: A cross-sectional survey was conducted, including 87 chronic pain patients from an academic outpatient pain center. RESULTS: The results show that general psychological acceptance (measured with the AAQ-II is a strong predictor of pain-related catastrophizing, independent of gender, age and pain intensity. Mindfulness (measured with the MAAS did not predict levels of pain-related catastrophizing. DISCUSSION: Acceptance of psychological experiences outside of pain itself is related to catastrophizing. Thus, acceptance seems to play a role in the pain experience and should be part of the treatment of chronic pain. The focus of the ACT treatment of chronic pain does not necessarily have to be on acceptance of pain per se, but may be aimed at acceptance of unwanted experiences in general. Mindfulness in the sense of "acting with awareness" is however not related to catastrophizing. Based on our research findings in comparisons with those of other authors, we recommend a broader conceptualization of mindfulness and the use of a multifaceted questionnaire for mindfulness instead of the unidimensional MAAS.

  20. Emergency obstetric care in Mali: catastrophic spending and its impoverishing effects on households

    Directory of Open Access Journals (Sweden)

    Catherine Arsenault

    2013-03-01

    Full Text Available OBJECTIVE: To investigate the frequency of catastrophic expenditures for emergency obstetric care, explore its risk factors, and assess the effect of these expenditures on households in the Kayes region, Mali. METHODS: Data on 484 obstetric emergencies (242 deaths and 242 near-misses were collected in 2008-2011. Catastrophic expenditure for emergency obstetric care was assessed at different thresholds and its associated factors were explored through logistic regression. A survey was subsequently administered in a nested sample of 56 households to determine how the catastrophic expenditure had affected them. FINDINGS: Despite the fee exemption policy for Caesareans and the maternity referral-system, designed to reduce the financial burden of emergency obstetric care, average expenses were 152 United States dollars (equivalent to 71 535 Communauté Financière Africaine francs and 20.7 to 53.5% of households incurred catastrophic expenditures. High expenditure for emergency obstetric care forced 44.6% of the households to reduce their food consumption and 23.2% were still indebted 10 months to two and a half years later. Living in remote rural areas was associated with the risk of catastrophic spending, which shows the referral system's inability to eliminate financial obstacles for remote households. Women who underwent Caesareans continued to incur catastrophic expenses, especially when prescribed drugs not included in the government-provided Caesarean kits. CONCLUSION: The poor accessibility and affordability of emergency obstetric care has consequences beyond maternal deaths. Providing drugs free of charge and moving to a more sustainable, nationally-funded referral system would reduce catastrophic expenses for households during obstetric emergencies.

  1. 22 CFR 71.7 - Reports on catastrophes abroad.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Reports on catastrophes abroad. 71.7 Section 71... catastrophes abroad. Whenever a great catastrophe occurs abroad, either on land or on sea, the officer within whose district the catastrophe takes place or into whose district the survivors are brought shall...

  2. Research on catastrophe control in 1-D system

    Institute of Scientific and Technical Information of China (English)

    SUN Yao; TANG Li-ping; LI Xue-lian

    2003-01-01

    A new method of catastrophe control is described in one dimension nonlinear system. Catastrophe control based on catastrophe theory is a brand new area for control theory. A certain catastrophe is created at a desired location by appropriate control, which has preferred properties. Washout filter is presented and applied to preserve the original equilibrium of a system. Washout filter aided dynamic feedback controller is developed for the creation of catastrophe, and an example is given to illustrate the process. Catastrophe control may provide a new way of designing warning signals of impending collapse or catastrophe for monitoring and control purposes.

  3. Pricing for Catastrophe Bonds Based on Expected-value Model

    Directory of Open Access Journals (Sweden)

    Junfei Chen

    2013-02-01

    Full Text Available As the catastrophes cannot be avoided and result in huge economic losses, therefore the compensation issue for catastrophe losses become an important research topic. Catastrophe bonds can effectively disperse the catastrophe risks which mainly undertaken by the government and the insurance companies currently and focus on capital more effectively in broad capital market, therefore to be an ideal catastrophe securities product. This study adopts Expectancy Theory to supplement and improve the pricing of catastrophe bonds based on Value Theory. A model of expected utility is established to determine the conditions of the expected revenue R of catastrophe bonds. The pricing model of the value function is used to get the psychological value of R,U (R-R‾, for catastrophe bonds. Finally, the psychological value is improved by the value according to expected utility and this can more accurately evaluate catastrophe bonds at a reasonable price. This research can provide decision-making for the pricing of catastrophe bonds.

  4. Downward Catastrophe of Solar Magnetic Flux Ropes

    Science.gov (United States)

    Zhang, Quanhao; Wang, Yuming; Hu, Youqiu; Liu, Rui

    2016-07-01

    2.5-dimensional time-dependent ideal magnetohydrodynamic (MHD) models in Cartesian coordinates were used in previous studies to seek MHD equilibria involving a magnetic flux rope embedded in a bipolar, partially open background field. As demonstrated by these studies, the equilibrium solutions of the system are separated into two branches: the flux rope sticks to the photosphere for solutions at the lower branch but is suspended in the corona for those at the upper branch. Moreover, a solution originally at the lower branch jumps to the upper, as the related control parameter increases and reaches a critical value, and the associated jump is here referred to as an upward catastrophe. The present paper advances these studies in three aspects. First, the magnetic field is changed to be force-free; the system still experiences an upward catastrophe with an increase in each control parameter. Second, under the force-free approximation, there also exists a downward catastrophe, characterized by the jump of a solution from the upper branch to the lower. Both catastrophes are irreversible processes connecting the two branches of equilibrium solutions so as to form a cycle. Finally, the magnetic energy in the numerical domain is calculated. It is found that there exists a magnetic energy release for both catastrophes. The Ampère's force, which vanishes everywhere for force-free fields, appears only during the catastrophes and does positive work, which serves as a major mechanism for the energy release. The implications of the downward catastrophe and its relevance to solar activities are briefly discussed.

  5. Environmental catastrophes under time-inconsistent preference

    Energy Technology Data Exchange (ETDEWEB)

    Michielsen, T.

    2013-02-15

    I analyze optimal natural resource use in an intergenerational model with the risk of a catastrophe. Each generation maximizes a weighted sum of discounted utility (positive) and the probability that a catastrophe will occur at any point in the future (negative). The model generates time inconsistency as generations disagree on the relative weights on utility and catastrophe prevention. As a consequence, future generations emit too much from the current generation's perspective and a dynamic game ensues. I consider a sequence of models. When the environmental problem is related to a scarce exhaustible resource, early generations have an incentive to reduce emissions in Markov equilibrium in order to enhance the ecosystem's resilience to future emissions. When the pollutant is expected to become obsolete in the near future, early generations may however increase their emissions if this reduces future emissions. When polluting inputs are abundant and expected to remain essential, the catastrophe becomes a self-fulfilling prophecy and the degree of concern for catastrophe prevention has limited or even no effect on equilibrium behaviour.

  6. Valuing Catastrophe Bonds Involving Credit Risks

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2014-01-01

    Full Text Available Catastrophe bonds are the most important products in catastrophe risk securitization market. For the operating mechanism, CAT bonds may have a credit risk, so in this paper we consider the influence of the credit risk on CAT bonds pricing that is different from the other literature. We employ the Jarrow and Turnbull method to model the credit risks and get access to the general pricing formula using the Extreme Value Theory. Furthermore, we present an empirical pricing study of the Property Claim Services data, where the parameters in the loss function distribution are estimated by the MLE method and the default probabilities are deduced by the US financial market data. Then we get the catastrophe bonds value by the Monte Carlo method.

  7. On a new global catastrophic ICT model

    DEFF Research Database (Denmark)

    Riaz, M. Tahir; Bhalerao, Dipashree M.; Madsen, Ole Brun;

    2011-01-01

    Many parts of India are prone to natural disasters, particularly caused by earthquakes and floods because of its geographical location. The Catastrophic areas can be rural, remote or urban anywhere in the world. It has been understood that earthquakes directly do not cause causalities but instead...

  8. 78 FR 52832 - Catastrophic Risk Protection Endorsement

    Science.gov (United States)

    2013-08-27

    .... See the Notice related to 7 CFR part 3015, subpart V, published at 48 FR 29115, June 24, 1983... the Federal Register at 76 FR 50929-50931. The public was afforded 60 days to submit written comments... Federal Crop Insurance Corporation 7 CFR Part 402 RIN 0563-AC31 Catastrophic Risk Protection...

  9. THE NONLINEAR CUSP-CATASTROPHE MODEL OF THE SEDIMENT TRANSPORT RATE

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the catastrophe theory of nonlinear science,the intensity of water-flow and the coefficient of non-uniformsediment m are regarded as two bound variables, and the in-tensity of bed-load transport Φ as the state variable in the mo-tion of non-uniform sediment in cusp-catastrophe model.Based on the standard equation of the cusp-catastrophe theo-ry, the relation equation between the intensity of bed-loadtransport Φ and the intensity of water-flow has been derivedby used coordinate transform and topology transform. The e-quation of bed load transport rate was built on the cusp-catas-trophe theory of nonlinear science. The others are applied toverify this equation, that the results calculated by the cusp-ca-tastrophe equation agree well with the other equations. Thisindicates that the cusp-catastrophe equation is reasonable, and the results fully reflect the characteristics of threshold motionand transport of non-uniform sediment. The purpose of thispaper is to explore the incipient motion and transport laws ofnon-uniform sediment from the viewpoint of nonlinear science.

  10. INCORPORATING CATASTROPHES INTO INTEGRATED ASSESSMENT: SCIENCE, IMPACTS, AND ADAPTATION

    Science.gov (United States)

    Incorporating potential catastrophic consequences into integrated assessment models of climate change has been a top priority of policymakers and modelers alike. We review the current state of scientific understanding regarding three frequently mentioned geophysical catastrophes,...

  11. CATASTROPHE FRACTURE OF THIN-WALL PRESSURE TUBES

    Institute of Scientific and Technical Information of China (English)

    魏德敏; 杨桂通

    2002-01-01

    Catastrophe theory was used to investigate the fracture behavior of thin-wall cylindrical tubes subjected to nternal explosive pressure. Based on the energy theory and catastrophe theory, a cusp catastrophe model for the fracture was established, and a critical condition associated with the model is given.

  12. Axial and focal-plane diffraction catastrophe integrals

    Energy Technology Data Exchange (ETDEWEB)

    Berry, M V [H H Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Howls, C J [School of Mathematics, University of Southampton, Southampton, SO17 1BJ (United Kingdom)

    2010-09-17

    Exact expressions in terms of Bessel functions are found for some of the diffraction catastrophe integrals that decorate caustics in optics and mechanics. These are the axial and focal-plane sections of the elliptic and hyperbolic umbilic diffraction catastrophes, and symmetric elliptic and hyperbolic unfoldings of the X{sub 9} diffraction catastrophes. These representations reveal unexpected relations between the integrals.

  13. CARA Risk Assessment Thresholds

    Science.gov (United States)

    Hejduk, M. D.

    2016-01-01

    Warning remediation threshold (Red threshold): Pc level at which warnings are issued, and active remediation considered and usually executed. Analysis threshold (Green to Yellow threshold): Pc level at which analysis of event is indicated, including seeking additional information if warranted. Post-remediation threshold: Pc level to which remediation maneuvers are sized in order to achieve event remediation and obviate any need for immediate follow-up maneuvers. Maneuver screening threshold: Pc compliance level for routine maneuver screenings (more demanding than regular Red threshold due to additional maneuver uncertainty).

  14. On Catastrophe and Cavitation for Spherical Cavity

    Institute of Scientific and Technical Information of China (English)

    MingJIN; KefuHUANG; 等

    1999-01-01

    This work deals with catastrophe of a spherical cavity and cavitation of a spherical cavity for Hooke material with 1/2 Poisson's ratio.A nonlinear problem.which is the Cauchy traction problem,is solved analytically.The governing equations are written on the deformed region or on the present configuration.And the conditions are described on moving boundary.A closed form solution is found.Furthermore,a bifurcation solution in closed form is given from the trivial homogeneous solution of a solid sphere.The results indicate that there is a tangent bifurcation on the displacement-load curve for a sphere with a cavity.On the tangent bifurcation point,the cavity grows up suddenly,which is a kind of catastrophe,And there is a pitchfork bifurcation on the displacement-load curve for a solid sphere.On the pitchfork bifurcation point.there is a cavitation in the solid sphere.

  15. Microtubule dynamics: Caps, catastrophes, and coupled hydrolysis

    DEFF Research Database (Denmark)

    Flyvbjerg, H.; Holy, T.E.; Leibler, S.

    1996-01-01

    An effective theory is formulated for the dynamics of the guanosine triphosphate (GTP) cap believed to stabilize growing microtubules. The theory provides a ''coarse-grained'' description of the cap's dynamics. ''Microscopic'' details, such as the microtubule lattice structure and the fate of its...... data. A constant nonzero catastrophe rare, identical for both microtubule ends, is predicted at large growth rates. The delay time for dilution-induced catastrophes is stochastic with a simple distribution that fits the experimental one and, like the experimental one, does not depend on the rate of....... A recent experimental result for the size of the minimal cap that can stabilize a microtubule is shown to agree with the result predicted by the cap model, after its parameters have been extracted from previous experimental results. Thus the effective theory and cap model presented here provide a...

  16. Nonlinear physics: Catastrophe, chaos and complexity

    International Nuclear Information System (INIS)

    Currently in the world of physics, there is open debate on the role of the three C's - catastrophe, chaos and complexity. Seen as new ideas or paradigms, incapable of being harmonized within the realm of traditional physics, these terms seem to be creating turmoil in the classical physics establishment whose foundations date back to the early seventeenth century. This paper first defines catastrophe, chaos and complexity and shows how these terms are all connected to nonlinear dynamics and how they have long since been present within scientific treatises. It also evidences the relationship of the three C's with the concept of organization, inappropriately called self-organization, and with recognition and decisional strategies of cognitive systems. Relevant to natural science, the development of these considerations is necessitating the re-examination of the role and capabilities of human knowledge and a return to inter-disciplinary scientific-philosophical debate

  17. Scaling law characterizing the dynamics of the transition of HIV-1 to error catastrophe

    Science.gov (United States)

    Gupta, Vipul; Dixit, Narendra M.

    2015-10-01

    Increasing the mutation rate, μ , of viruses above a threshold, {μ }c, has been predicted to trigger a catastrophic loss of viral genetic information and is being explored as a novel intervention strategy. Here, we examine the dynamics of this transition using stochastic simulations mimicking within-host HIV-1 evolution. We find a scaling law governing the characteristic time of the transition: τ ≈ 0.6/≤ft(μ -{μ }c\\right). The law is robust to variations in underlying evolutionary forces and presents guidelines for treatment of HIV-1 infection with mutagens. We estimate that many years of treatment would be required before HIV-1 can suffer an error catastrophe.

  18. Valuing Catastrophic Losses for Perennial Agricultural Crops

    OpenAIRE

    Adams, Damian C.; Kilmer, Richard L.; Moss, Charles B.; Schmitz, Andrew

    2003-01-01

    Courts are often required to estimate changes in welfare to agricultural operations from catastrophic events. For example, courts must assign damages in lawsuits, such as with pesticide drift cases, or determine 'just compensation' when the government takes private land for public use, as with the removal of dairy farms from environmentally sensitive land or destruction of canker-contaminated citrus trees. In economics, the traditional method of estimating changes in producer welfare is the c...

  19. Catastrophic health expenditure and impoverishment in Mongolia

    OpenAIRE

    Dorjdagva, Javkhlanbayar; Batbaatar, Enkhjargal; Svensson, Mikael; Dorjsuren, Bayarsaikhan; Kauhanen, Jussi

    2016-01-01

    Background The social health insurance coverage is relatively high in Mongolia; however, escalation of out-of-pocket payments for health care, which reached 41 % of the total health expenditure in 2011, is a policy concern. The aim of this study is to analyse the incidence of catastrophic health expenditures and to measure the rate of impoverishment from health care payments under the social health insurance scheme in Mongolia. Methods We used the data from the Household Socio-Economic Survey...

  20. Recent catastrophic landslides and mitigation in China

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Increasing population density and development of mountainous terrain have brought human settlements within reach of landslide hazards.In recent years,due to the shortening of return period for severe natural events such as heavy rainfall,snowline retreating,great earthquake together with human activities,catastrophic landslides happened more frequently than before,resulting in large-scale casualties due to the increasing occurrences of rapid long-runout rock avalanches,especially in China.This paper present...

  1. Catastrophic Consequences of Kicking the Chameleon

    OpenAIRE

    Erickcek, Adrienne L.; Barnaby, Neil; Burrage, Clare; Huang, Zhiqi

    2013-01-01

    The physics of the "dark energy" that drives the current cosmological acceleration remains mysterious, and the dark sector may involve new light dynamical fields. If these light scalars couple to matter, a screening mechanism must prevent them from mediating an unacceptably strong fifth force locally. Here we consider a concrete example: the chameleon mechanism. We show that the same coupling between the chameleon field and matter employed by the screening mechanism also has catastrophic cons...

  2. Catastrophic Natural Disasters and Economic Growth

    OpenAIRE

    Cavallo, Eduardo; Galiani, Sebastian; Noy, Ilan; Pantano, Juan

    2010-01-01

    We examine the short and long run average causal impact of catastrophic natural disasters on economic growth by combining information from comparative case studies. We assess the counterfactual of the cases studied by constructing synthetic control groups taking advantage of the fact that the timing of large sudden natural disasters is an exogenous event. We find that only extremely large disasters have a negative effect on output both in the short and long run. However, we also show that thi...

  3. Fitting the Cusp Catastrophe in R: A cusp Package Primer

    Directory of Open Access Journals (Sweden)

    Raoul P. P. P. Grasman

    2009-11-01

    Full Text Available Of the seven elementary catastrophes in catastrophe theory, the “cusp” model is the most widely applied. Most applications are however qualitative. Quantitative techniques for catastrophe modeling have been developed, but so far the limited availability of flexible software has hindered quantitative assessment. We present a package that implements and extends the method of Cobb (Cobb and Watson 1980; Cobb, Koppstein, and Chen 1983, and makes it easy to quantitatively fit and compare different cusp catastrophe models in a statistically principled way. After a short introduction to the cusp catastrophe, we demonstrate the package with two instructive examples.

  4. Paleomagnetic study of the Tunguska catastrophe epicenter

    Science.gov (United States)

    Gladysheva, O. G.; Popov, V. V.

    2016-03-01

    The Tunguska catastrophe occurred in the area of the East Siberian magnetic anomaly on June 30, 1908. The epicenter of the explosive destruction of the Tunguska cosmic body (TCB) was above the central neck of a paleovolcano (Mt. Stoikovich). According to the paleomagnetic data available, the bedrocks on the top of Mt. Stoikovich carry remanent magnetization, which is substantially higher than that in rocks from neighboring mountains. Analysis of the results of paleomagnetic measurements of rock samples collected in the vicinity of the Tunguska catastrophe epicenter showed that the destruction of the cosmic body was accompanied by the formation of multidirectional magnetic fields, which provide disturbances spreading over a distance of 25 km from the epicenter. The chaotic distribution pattern of magnetization vectors measured in the soil in the vicinity of the Tunguska catastrophe epicenter confirms the previously expressed assumption that destruction of the TCB was accompanied with multiple discharges. According to this, we can conclude that the matter of the Tunguska cosmic body was dispersed around the epicenter in a zone approximately 25 km in diameter.

  5. A critical look at catastrophe risk assessments

    CERN Document Server

    Kent, A

    2004-01-01

    Recent papers by Busza et al. (BJSW) and Dar et al. (DDH) argue that astrophysical data can be used to establish bounds on the risk of a catastrophe in forthcoming collider experiments. The safety case set out by BJSW does not rely on these bounds, but on theoretical arguments, which BJSW find sufficiently compelling. However, DDH and other commentators (initially including BJSW) have suggested that the astrophysical bounds alone do give sufficient reassurance. This seems unsupportable when the bounds are expressed in terms of expected cost. For example, DDH's main bound, $p_{\\rm catastrophe} < 2 \\times 10^{-8}$, implies only that the expectation value of the number of deaths is bounded by 120. We thus reappraise the DDH and BJSW risk bounds by comparing risk policy in other areas. We find that requiring a catastrophe risk of no higher than 10^{-15} is necessary to be consistent with established policy for risk optimisation from radiation hazards, even if highly risk tolerant assumptions are made. A respec...

  6. Catastrophic fragmentation of asteroids: Evidence from meteorites

    Science.gov (United States)

    Keil, K.; Haack, H.; Scott, E. R. D.

    1994-01-01

    Meteorites are impact-derived fragments from approximately 85 parent bodies. For seven of these bodies, the meteorites record evidence suggesting that they may have been catastrophically fragmented. We identify three types of catastrophic events: (1) impact and reassemble events greater than 4.4 Gy ago, involving molten or very hot parent bodies (greater than 1200 C); this affected the parent bodies of the ureilites, Shallowater, and the mesosiderites. In each case, the fragments cooled rapidly (approximately 1-1000 C/day) and then reassembled. (2) Later impacts involving cold bodies which, in some cases, reassembled; this occurred on the H and L ordinary chondrite parent bodies. The L parent body probably suffered another catastrophic event about 500 My ago. (3) Recent impacts of cold, multi-kilometer-sized bodies that generated meter-sized meteoroids; this occurred on the parent bodies of the IIIAB irons (650 My ago), the IVA irons (400 My ago), and the H ordinary chondrite (7 My ago).

  7. Downward catastrophe of solar magnetic flux ropes

    CERN Document Server

    Zhang, Quanhao; Hu, Youqiu; Liu, Rui

    2016-01-01

    2.5D time-dependent ideal magnetohydrodynamic (MHD) models in Cartesian coordinates were used in previous studies to seek MHD equilibria involving a magnetic flux rope embedded in a bipolar, partially open background field. As demonstrated by these studies, the equilibrium solutions of the system are separated into two branches: the flux rope sticks to the photosphere for solutions at the lower branch but is suspended in the corona for those at the upper branch. Moreover, a solution originally at the lower branch jumps to the upper, as the related control parameter increases and reaches a critical value, and the associated jump is here referred to as upward catastrophe. The present paper advances these studies in three aspects. First, the magnetic field is changed to be force-free. The system still experiences an upward catastrophe with an increase in each control parameter. Secondly, under the force-free approximation, there also exists a downward catastrophe, characterized by a jump of a solution from the u...

  8. Proteomic profiling revealed the functional networks associated with mitotic catastrophe of HepG2 hepatoma cells induced by 6-bromine-5-hydroxy-4-methoxybenzaldehyde

    International Nuclear Information System (INIS)

    Mitotic catastrophe, a form of cell death resulting from abnormal mitosis, is a cytotoxic death pathway as well as an appealing mechanistic strategy for the development of anti-cancer drugs. In this study, 6-bromine-5-hydroxy-4-methoxybenzaldehyde was demonstrated to induce DNA double-strand break, multipolar spindles, sustain mitotic arrest and generate multinucleated cells, all of which indicate mitotic catastrophe, in human hepatoma HepG2 cells. We used proteomic profiling to identify the differentially expressed proteins underlying mitotic catastrophe. A total of 137 differentially expressed proteins (76 upregulated and 61 downregulated proteins) were identified. Some of the changed proteins have previously been associated with mitotic catastrophe, such as DNA-PKcs, FoxM1, RCC1, cyclin E, PLK1-pT210, 14-3-3σ and HSP70. Multiple isoforms of 14-3-3, heat-shock proteins and tubulin were upregulated. Analysis of functional significance revealed that the 14-3-3-mediated signaling network was the most significantly enriched for the differentially expressed proteins. The modulated proteins were found to be involved in macromolecule complex assembly, cell death, cell cycle, chromatin remodeling and DNA repair, tubulin and cytoskeletal organization. These findings revealed the overall molecular events and functional signaling networks associated with spindle disruption and mitotic catastrophe. - Graphical abstract: Display Omitted Research highlights: → 6-bromoisovanillin induced spindle disruption and sustained mitotic arrest, consequently resulted in mitotic catastrophe. → Proteomic profiling identified 137 differentially expressed proteins associated mitotic catastrophe. → The 14-3-3-mediated signaling network was the most significantly enriched for the altered proteins. → The macromolecule complex assembly, cell cycle, chromatin remodeling and DNA repair, tubulin organization were also shown involved in mitotic catastrophe.

  9. Granular motions near the threshold of entrainment

    Science.gov (United States)

    Valyrakis, Manousos; Alexakis, athanasios-Theodosios

    2016-04-01

    Our society is continuously impacted by significant weather events many times resulting in catastrophes that interrupt our normal way of life. In the context of climate change and increasing urbanisation these "extreme" hydrologic events are intensified both in magnitude and frequency, inducing costs of the order of billions of pounds. The vast majority of such costs and impacts (even more to developed societies) are due to water related catastrophes such as the geomorphic action of flowing water (including scouring of critical infrastructure, bed and bank destabilisation) and flooding. New tools and radically novel concepts are in need, to enable our society becoming more resilient. This presentation, emphasises the utility of inertial sensors in gaining new insights on the interaction of flow hydrodynamics with the granular surface at the particle scale and for near threshold flow conditions. In particular, new designs of the "smart-sphere" device are discussed with focus on the purpose specific sets of flume experiments, designed to identify the exact response of the particle resting at the bed surface for various below, near and above threshold flow conditions. New sets of measurements are presented for particle entrainment from a Lagrangian viewpoint. Further to finding direct application in addressing real world challenges in the water sector, it is shown that such novel sensor systems can also help the research community (both experimentalists and computational modellers) gain a better insight on the underlying processes governing granular dynamics.

  10. Targeting pain catastrophization in patients with fibromyalgia using virtual reality exposure therapy: a proof-of-concept study.

    Science.gov (United States)

    Morris, Linzette Deidrè; Louw, Quinette Abegail; Grimmer, Karen Anne; Meintjes, Ernesta

    2015-11-01

    [Purpose] Pain catastrophizing is a key predictor of poor compliance to exercises among patients with fibromyalgia syndrome. Alteration of pain catastrophizing in this group is thus warranted. This study aimed to provide proof-of-concept of a novel virtual reality exposure therapy program as treatment for exercise-related pain catastrophizing in patients with fibromyalgia syndrome. [Subjects and Methods] An exploratory, case-controlled study was conducted (fibromyalgia syndrome group and matched control group). Functional magnetic resonance imaging was used to acquire neural correlates. The functional magnetic resonance imaging task consisted of two stimuli: active (exercise activity visuals) and passive (relaxing visuals). Structural images and blood-oxygenation-level-dependent contrasts were acquired for the conditions and compared within subjects/groups and between groups. Statistic images were thresholded using corrected clusters (determined by Z>2.3; level of significance: 0.05). [Results] Thirteen fibromyalgia syndrome subjects and nine healthy matched controls were included. The right inferior frontal gyrus, right middle frontal gyrus, right posterior cerebellum, left thalamus, and left supramarginal gyrus were activated in the fibromyalgia syndrome subjects. [Conclusion] The study results provide preliminary proof indicating that exposing patients with fibromyalgia syndrome to visuals of exercises elicits neurophysiological changes in functional brain areas associated with pain catastrophization and add to the current body of knowledge regarding the possibility of objectively identifying cognitive behavioral strategies like pain catastrophization. PMID:26696719

  11. Threshold Concepts in Biochemistry

    Science.gov (United States)

    Loertscher, Jennifer

    2011-01-01

    Threshold concepts can be identified for any discipline and provide a framework for linking student learning to curricular design. Threshold concepts represent a transformed understanding of a discipline, without which the learner cannot progress and are therefore pivotal in learning in a discipline. Although threshold concepts have been…

  12. Observational Features of Large-Scale Structures as Revealed by the Catastrophe Model of Solar Eruptions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Large-scale magnetic structures are the main carrier of major eruptions in the solar atmosphere. These structures are rooted in the photosphere and are driven by the unceasing motion of the photospheric material through a series of equilibrium configurations. The motion brings energy into the coronal magnetic field until the system ceases to be in equilibrium. The catastrophe theory for solar eruptions indicates that loss of mechanical equilibrium constitutes the main trigger mechanism of major eruptions, usually shown up as solar flares,eruptive prominences, and coronal mass ejections (CMEs). Magnetic reconnection which takes place at the very beginning of the eruption as a result of plasma instabilities/turbulence inside the current sheet, converts magnetic energy into heating and kinetic energy that are responsible for solar flares, and for accelerating both plasma ejecta (flows and CMEs) and energetic particles. Various manifestations are thus related to one another, and the physics behind these relationships is catastrophe and magnetic reconnection. This work reports on recent progress in both theoretical research and observations on eruptive phenomena showing the above manifestations. We start by displaying the properties of large-scale structures in the corona and the related magnetic fields prior to an eruption, and show various morphological features of the disrupting magnetic fields. Then, in the framework of the catastrophe theory,we look into the physics behind those features investigated in a succession of previous works,and discuss the approaches they used.

  13. Catastrophic Fires in the Russian Federation

    Science.gov (United States)

    Sukhinin, A. I.; Soja, A. J.; McRae, D. J.; Cahoon, D. R.; Stocks, B. J.; Dubrovskaya, O. A.; Ji-Zhong, J.; Flannigan, M.; DeGroot, B.; Westberg, D.; Stackhouse, P. W.; Conard, S. G.; Hao, W. M.

    2011-12-01

    Impacts of climate change on the severity of wildfires and the implications for carbon emissions in the boreal zone are globally significant because Russia contains two-thirds of the world's boreal forest and peat lands. Wildfires in Russia burn from 2 to 20 million ha annually, depending on burning conditions, yet quantification of trends in fire patterns is hampered by the lack of accurate historic fire data. Official Russian wildfire records greatly underestimate burned areas. However, satellite data for Russia have become easily available for assessing area burned since 1980, and we are in the process of analyzing these data to map historic burned area and fire patterns. Catastrophic fire refers to large, uncontrollable fires that are associated with extreme weather conditions. In Russia, major catastrophic fire events are associated with stable anticyclonic systems, which lead to severe drought that supports extreme fire behavior. These forest fires result in large areas burned and high consumption of vegetation and organic soil horizons. Additionally, thick smoke can reduce visibility, which often paralyzes suppression efforts. In recent years, there have been several large and often economically devastating fire complexes across Russia (European Russia, Tyva, Sakha, Chita and the Far East). We present evidence of the association of these large fires with very high or extreme fire weather danger. We assert that these large fire systems have increased in severity in response to current changes in weather and climate, and we argue that catastrophic fires are likely to increase in the future, as climate warms in the northern hemisphere upper latitudes of Russia.

  14. A unified approach of catastrophic events

    Directory of Open Access Journals (Sweden)

    S. Nikolopoulos

    2004-01-01

    Full Text Available Although there is an accumulated charge of theoretical, computational, and numerical work, like catastrophe theory, bifurcation theory, stochastic and deterministic chaos theory, there is an important feeling that these matters do not completely cover the physics of real catastrophic events. Recent studies have suggested that a large variety of complex processes, including earthquakes, heartbeats, and neuronal dynamics, exhibits statistical similarities. Here we are studying in terms of complexity and non linear techniques whether isomorphic signatures emerged indicating the transition from the normal state to the both geological and biological shocks. In the last 15 years, the study of Complex Systems has emerged as a recognized field in its own right, although a good definition of what a complex system is, actually is eluded. A basic reason for our interest in complexity is the striking similarity in behaviour close to irreversible phase transitions among systems that are otherwise quite different in nature. It is by now recognized that the pre-seismic electromagnetic time-series contain valuable information about the earthquake preparation process, which cannot be extracted without the use of important computational power, probably in connection with computer Algebra techniques. This paper presents an analysis, the aim of which is to indicate the approach of the global instability in the pre-focal area. Non-linear characteristics are studied by applying two techniques, namely the Correlation Dimension Estimation and the Approximate Entropy. These two non-linear techniques present coherent conclusions, and could cooperate with an independent fractal spectral analysis to provide a detection concerning the emergence of the nucleation phase of the impending catastrophic event. In the context of similar mathematical background, it would be interesting to augment this description of pre-seismic electromagnetic anomalies in order to cover biological

  15. Disruptive event analysis: volcanism and igneous intrusion

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, B.M.

    1980-08-01

    An evaluation is made of the disruptive effects of volcanic activity with respect to long term isolation of radioactive waste through deep geologic storage. Three major questions are considered. First, what is the range of disruption effects of a radioactive waste repository by volcanic activity. Second, is it possible, by selective siting of a repository, to reduce the risk of disruption by future volcanic activity. And third, can the probability of repository disruption by volcanic activity be quantified. The main variables involved in the evaluation of the consequences of repository disruption by volcanic activity are the geometry of the magma-repository intersection (partly controlled by depth of burial) and the nature of volcanism. Potential radionuclide dispersal by volcanic transport within the biosphere ranges in distance from several kilometers to global. Risk from the most catastrophic types of eruptions can be reduced by careful site selection to maximize lag time prior to the onset of activity. Certain areas or volcanic provinces within the western United States have been sites of significant volcanism and should be avoided as potential sites for a radioactive waste repository. Examples of projection of future sites of active volcanism are discussed for three areas of the western United States. Probability calculations require two types of data: a numerical rate or frequency of volcanic activity and a numerical evaluation of the areal extent of volcanic disruption for a designated region. The former is clearly beyond the current state of art in volcanology. The latter can be approximated with a reasonable degree of satisfaction. In this report, simplified probability calculations are attempted for areas of past volcanic activity.

  16. Disruptive event analysis: volcanism and igneous intrusion

    International Nuclear Information System (INIS)

    An evaluation is made of the disruptive effects of volcanic activity with respect to long term isolation of radioactive waste through deep geologic storage. Three major questions are considered. First, what is the range of disruption effects of a radioactive waste repository by volcanic activity. Second, is it possible, by selective siting of a repository, to reduce the risk of disruption by future volcanic activity. And third, can the probability of repository disruption by volcanic activity be quantified. The main variables involved in the evaluation of the consequences of repository disruption by volcanic activity are the geometry of the magma-repository intersection (partly controlled by depth of burial) and the nature of volcanism. Potential radionuclide dispersal by volcanic transport within the biosphere ranges in distance from several kilometers to global. Risk from the most catastrophic types of eruptions can be reduced by careful site selection to maximize lag time prior to the onset of activity. Certain areas or volcanic provinces within the western United States have been sites of significant volcanism and should be avoided as potential sites for a radioactive waste repository. Examples of projection of future sites of active volcanism are discussed for three areas of the western United States. Probability calculations require two types of data: a numerical rate or frequency of volcanic activity and a numerical evaluation of the areal extent of volcanic disruption for a designated region. The former is clearly beyond the current state of art in volcanology. The latter can be approximated with a reasonable degree of satisfaction. In this report, simplified probability calculations are attempted for areas of past volcanic activity

  17. Bankruptcy by catastrophes for major multi-nationals: stock exchange sensitivity for three catastrophes

    NARCIS (Netherlands)

    Van Gulijk, C.; Ale, B.J.M.

    2012-01-01

    This paper investigates the effect of major catastrophes have on stock exchange values for the major multi-nationals. The paper demonstrates that the Sharpe analysis is more sensitive in identifying effects than just following the daily stock values for assessing market response. It was found that m

  18. Factors underlying companies response to supply chain disruption: a grounded theory approach

    OpenAIRE

    Chadist, Patrapa

    2012-01-01

    A wide range of recent man-made and natural disasters has demonstrated the importance of managing disruption risk in global supply chains. This research argues that supply chain disruptions are, de facto, unavoidable and consequently all complex supply chains can be considered inherently risky. This research focuses on a relatively unexplored issue in supply chain risk management, asking and answering the question of how companies specifically use time to respond to catastrophic events of low...

  19. Catastrophizing and Parental Response to Child Symptom Complaints

    OpenAIRE

    Langer, Shelby L.; Romano, Joan M.; Levy, Rona L; Walker, Lynn S.; Whitehead, William E.

    2009-01-01

    This study investigated whether catastrophic thinking about pain by children with functional abdominal pain or by their parents is associated with health outcomes in the child. Subjects were 132 parent-child dyads. Child catastrophizing predicted child depression, anxiety and functional disability. Parents’ catastrophizing cognitions about their own pain predicted self-reported protective responses to their children’s abdominal pain (responding in ways that encourage illness behavior). Protec...

  20. Averting Catastrophes: The Strange Economics of Scylla and Charybdis

    OpenAIRE

    Martin, Ian; Pindyck, R. S.

    2014-01-01

    How should we evaluate public policies or projects to avert, or reduce the likelihood of, a catastrophic event? Examples might include inspection and surveillance programs to avert nuclear terrorism, investments in vaccine technologies to help respond to a "mega-virus," or the construction of levees to avert major flooding. A policy to avert a particular catastrophe considered in isolation might be evaluated in a cost-benefit framework. But because society faces multiple potential catastrophe...

  1. Mutation accumulation and the catastrophic senescence of Pacific salmon

    CERN Document Server

    Penna, T J P; Stauffer, D; Stauffer, Dietrich

    1995-01-01

    The bit-string model of biological aging is used to simulate the catastrophic senescence of Pacific Salmon. We have shown that reproduction occuring only once and at a fixed age is the only ingredient needed to explain the catastrophic senescence according the mutation accumulation theory. Several results are presented, some of them with up to 10^8 fishes, showing how the survival rates in catastrophic senescence are affected by changes in the parameters of the model.

  2. Inside Money, Procyclical Leverage, and Banking Catastrophes

    Science.gov (United States)

    Brummitt, Charles D.; Sethi, Rajiv; Watts, Duncan J.

    2014-01-01

    We explore a model of the interaction between banks and outside investors in which the ability of banks to issue inside money (short-term liabilities believed to be convertible into currency at par) can generate a collapse in asset prices and widespread bank insolvency. The banks and investors share a common belief about the future value of certain long-term assets, but they have different objective functions; changes to this common belief result in portfolio adjustments and trade. Positive belief shocks induce banks to buy risky assets from investors, and the banks finance those purchases by issuing new short-term liabilities. Negative belief shocks induce banks to sell assets in order to reduce their chance of insolvency to a tolerably low level, and they supply more assets at lower prices, which can result in multiple market-clearing prices. A sufficiently severe negative shock causes the set of equilibrium prices to contract (in a manner given by a cusp catastrophe), causing prices to plummet discontinuously and banks to become insolvent. Successive positive and negative shocks of equal magnitude do not cancel; rather, a banking catastrophe can occur even if beliefs simply return to their initial state. Capital requirements can prevent crises by curtailing the expansion of balance sheets when beliefs become more optimistic, but they can also force larger price declines. Emergency asset price supports can be understood as attempts by a central bank to coordinate expectations on an equilibrium with solvency. PMID:25136959

  3. Inside money, procyclical leverage, and banking catastrophes.

    Science.gov (United States)

    Brummitt, Charles D; Sethi, Rajiv; Watts, Duncan J

    2014-01-01

    We explore a model of the interaction between banks and outside investors in which the ability of banks to issue inside money (short-term liabilities believed to be convertible into currency at par) can generate a collapse in asset prices and widespread bank insolvency. The banks and investors share a common belief about the future value of certain long-term assets, but they have different objective functions; changes to this common belief result in portfolio adjustments and trade. Positive belief shocks induce banks to buy risky assets from investors, and the banks finance those purchases by issuing new short-term liabilities. Negative belief shocks induce banks to sell assets in order to reduce their chance of insolvency to a tolerably low level, and they supply more assets at lower prices, which can result in multiple market-clearing prices. A sufficiently severe negative shock causes the set of equilibrium prices to contract (in a manner given by a cusp catastrophe), causing prices to plummet discontinuously and banks to become insolvent. Successive positive and negative shocks of equal magnitude do not cancel; rather, a banking catastrophe can occur even if beliefs simply return to their initial state. Capital requirements can prevent crises by curtailing the expansion of balance sheets when beliefs become more optimistic, but they can also force larger price declines. Emergency asset price supports can be understood as attempts by a central bank to coordinate expectations on an equilibrium with solvency. PMID:25136959

  4. Gradient catastrophe and flutter in vortex filament dynamics

    CERN Document Server

    Konopelchenko, B G

    2011-01-01

    Gradient catastrophe and flutter instability in the motion of vortex filament within the localized induction approximation are analyzed. It is shown that the origin if this phenomenon is in the gradient catastrophe for the dispersionless Da Rios system which describes motion of filament with slow varying curvature and torsion. Geometrically this catastrophe manifests as a rapid oscillation of a filament curve in a point that resembles the flutter of airfoils. Analytically it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painlev\\'e-I equation.

  5. Gradient catastrophe and flutter in vortex filament dynamics

    International Nuclear Information System (INIS)

    Gradient catastrophe and flutter instability in the motion of a vortex filament within the localized induction approximation are analyzed. It is shown that the origin of this phenomenon is in the gradient catastrophe for the dispersionless Da Rios system which describes the motion of a filament with slow varying curvature and torsion. Geometrically, this catastrophe manifests as a rapid oscillation of a filament curve in a point that resembles the flutter of airfoils. Analytically, it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painleve-I equation. (fast track communication)

  6. Gradient catastrophe and flutter in vortex filament dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Konopelchenko, B G [Dipartimento di Fisica, Universita del Salento and INFN, Sezione di Lecce, 73100 Lecce (Italy); Ortenzi, G, E-mail: giovanni.ortenzi@unimib.it [Dipartimento di Matematica Pura ed Applicazioni, Universita di Milano Bicocca, 20125 Milano (Italy)

    2011-10-28

    Gradient catastrophe and flutter instability in the motion of a vortex filament within the localized induction approximation are analyzed. It is shown that the origin of this phenomenon is in the gradient catastrophe for the dispersionless Da Rios system which describes the motion of a filament with slow varying curvature and torsion. Geometrically, this catastrophe manifests as a rapid oscillation of a filament curve in a point that resembles the flutter of airfoils. Analytically, it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painleve-I equation. (fast track communication)

  7. Ecological catastrophes: threshold responses to climate, soil, and land use drivers of the dust bowl

    Science.gov (United States)

    The Dust Bowl was one of the largest ecological disasters, yet is among the least well-studied for regional-scale impacts. Much of the central grasslands region (CGR) of North America experienced a multi-year drought in the 1930s that combined with poor land management practices to result in broad-s...

  8. Corporate Demand for Insurance: An Empirical Analysis of the U.S. Market for Catastrophe and Non-Catastrophe Risks

    OpenAIRE

    Michel-Kerjan, Erwann; Raschky, Paul A.; Kunreuther, Howard C.

    2009-01-01

    This paper tests some existing theories developed over the past 25 years on corporate demand for insurance. Using a unique dataset of 1,809 large U.S. corporations it provides the first empirical analysis that compares corporate demand for standard property insurance and for catastrophe coverage (here, terrorism). We find that larger companies are more likely to have some catastrophe coverage. Corporate demand for catastrophe insurance is found to be more price inelastic than insurance for no...

  9. Exact Threshold Circuits

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.

    2010-01-01

    We initiate a systematic study of constant depth Boolean circuits built using exact threshold gates. We consider both unweighted and weighted exact threshold gates and introduce corresponding circuit classes. We next show that this gives a hierarchy of classes that seamlessly interleave with the...... well-studied corresponding hierarchies defined using ordinary threshold gates. A major open problem in Boolean circuit complexity is to provide an explicit super-polynomial lower bound for depth two threshold circuits. We identify the class of depth two exact threshold circuits as a natural subclass of...... these where also no explicit lower bounds are known. Many of our results can be seen as evidence that this class is a strict subclass of depth two threshold circuits - thus we argue that efforts in proving lower bounds should be directed towards this class....

  10. The perils of thresholding

    CERN Document Server

    Font-Clos, Francesc; Deluca, Anna; Moloney, Nicholas R

    2014-01-01

    The thresholding of time series of activity or intensity is frequently used to define and differentiate events. This is either implicit, for example due to resolution limits, or explicit, in order to filter certain small scale physics from the supposed true asymptotic events. Thresholding the birth-death process, however, introduces a scaling region into the event size distribution, which is characterised by an exponent that is unrelated to the actual asymptote and is rather an artefact of thresholding. As a result, numerical fits of simulation data produce a range of exponents, with the true asymptote visible only in the tail of the distribution. This tail is increasingly difficult to sample as the threshold is increased. In the present case, the exponents and the spurious nature of the scaling region can be determined analytically, thus demonstrating the way in which thresholding conceals the true asymptote. The analysis also suggests a procedure for detecting the influence of the threshold by means of a da...

  11. Catastrophic Consequences of Kicking the Chameleon

    CERN Document Server

    Erickcek, Adrienne L; Burrage, Clare; Huang, Zhiqi

    2013-01-01

    The physics of the "dark energy" that drives the current cosmological acceleration remains mysterious, and the dark sector may involve new light dynamical fields. If these light scalars couple to matter, a screening mechanism must prevent them from mediating an unacceptably strong fifth force locally. Here we consider a concrete example: the chameleon mechanism. We show that the same coupling between the chameleon field and matter employed by the screening mechanism also has catastrophic consequences for the chameleon during the Universe's first minutes. The chameleon couples to the trace of the stress-energy tensor, which is temporarily non-zero in a radiation-dominated universe whenever a particle species becomes non-relativistic. These "kicks" impart a significant velocity to the chameleon field, causing its effective mass to vary non-adiabatically and resulting in the copious production of quantum fluctuations. Dissipative effects strongly modify the background evolution of the chameleon field, invalidati...

  12. Application of catastrophe theory to nuclear structure

    International Nuclear Information System (INIS)

    Three two-parameter models, one describing an A-body system (the atomic nucleus) and two describing many-body systems (the van der Waals gas and the ferroelectric (perovskite) system) are compared within the framework of catastrophe theory. It is shown that each has a critical point (second-order phase transition) when the two counteracting forces controlling it are in balance; further, each undergoes a first-order phase transition when one of the forces vanishes (the deforming force for the nucleus, the attractive force for the van der Waals gas, and the dielectric constant for the perovskite). Finally, when both parameters are kept constant, a kind of phase transition may occur at a critical angular momentum, critical pressure, and critical electric field. 3 figures, 1 table

  13. A model of major disruption in tokamaks

    International Nuclear Information System (INIS)

    A mechanism for the onset of the major disruption is proposed which considers the effect of magnetic stochasticity on the growth of the m=2 tearing mode. The toroidicity can cause stochasticity near the separatrix of the m=2 magnetic island which enhances the current viscosity, resulting in explosive growth. The threshold condition and the time scale of rapid growth are studied. The role of the toroidal coupling to the m=1 component is also discussed. (author)

  14. Experiments on Mixotrophic Protists and Catastrophic Darkness

    Science.gov (United States)

    Jones, Harriet; Cockell, Charles S.; Goodson, Claire; Price, Nicola; Simpson, Annika; Thomas, Benjamin

    2009-08-01

    Catastrophically darkened photic zone conditions in water bodies are postulated to be induced by a diversity of mechanisms that are recorded in the geological record, including asteroid and comet impacts and large-scale volcanic eruptions. Giant wildfires, such as those that followed the great fires in Siberia in 1915, have been directly shown to cause large reductions in sunlight penetrating to the ground. Previous studies on the response of phototrophs to s udden prolonged darkness have focused on the survival of axenic strains. In this paper, we describe laboratory experiments to investigate the survival and growth of isolated and mixed cultures of freshwater and marine mixotrophs after 6 months of darkness and in the low light that would follow these events. Mixotrophs could survive 6 months of darkness. Some species used dissolved organic carbon, which can be released from dead biomass after loss of light and was shown to improve feeding rates. Mixotrophs also improved the survival and subsequent growth of obligate phototrophs at low light levels when grown in mixed cultures. The ability of mixotrophs to switch from photosynthesis to heterotrophy following sudden darkening would not only allow them to survive but to grow and contribute to active food chains. The experiments suggest that, following the return of light, resumption of photosynthesis can be rapid. These experiments improve our understanding of the collapse of photosynthesis following catastrophic darkening and emphasize the important role of mixotrophy in the resilience of the photosynthetic biosphere during such periods. We speculate on the implications for the Cretaceous-Tertiary impact event and periods of global freezing.

  15. Grasshopper Population Ecology: Catastrophe, Criticality, and Critique

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Lockwood

    2008-06-01

    Full Text Available Grasshopper population dynamics are an important part of the North American rangeland ecosystem and an important factor in the economies that derive from the rangeland. Outbreak dynamics have plagued management strategies in the rangeland, and attempts to find simple, linear and mechanistic solutions to both understanding and predicting the dynamics have proved fruitless. These efforts to ground theory in a correspondence with the “real” world, including whether the population dynamics are ultimately density dependent or density independent, have generated abundant heat but little light. We suggest that a pragmatic approach, in which theories are taken to be “tools” rather than competing claims of truth, has greater promise to move ecological research in a constructive direction. Two recent non-linear approaches exploiting the tools of complexity science provide insights relevant to explaining and forecasting population dynamics. Observation and data collection were used to structure models derived from catastrophe theory and self-organized criticality. These models indicate that nonlinear processes are important in the dynamics of the outbreaks. And the conceptual structures of these approaches provide clear, albeit constrained or contingent, implications for pest managers. We show that, although these two frameworks, catastrophe theory and self-organized criticality, are very different, the frequency distributions of time series from both systems result in power law relationships. Further, we show that a simple lattice-based model, similar to SOC but structured on the biology of the grasshoppers gives a spatial time series similar to data over a 50-year span and the frequency distribution is also a power law relationship. This demonstration exemplifies how a “both–and” rather than an “either–or” approach to ecological modeling, in which the useful elements of particular theories or conceptual structures are extracted, may

  16. Determinants of Catastrophic Health Expenditure in Iran

    Directory of Open Access Journals (Sweden)

    M Ramezanian

    2013-01-01

    Full Text Available Background: This study will provide detailed specification of those variables and determinants of unpredictable health expenditure in Iran, and the requirements to reduce extensive effects of the factors affecting households’ payments for health and other goods and services inappropriately.Method: This study aims to identify measures of fair financing of health services and determinants of fair financing contribution, regarding the required share of households that prevents their catastrophic payments. In this regard, analysis of shares of households’ expenditures on main groups of goods and services in urban and rural areas and in groups of deciles in the statistics from households’ expenditure surveys was applied.Results: The growth of spending in nominal values within the years 2002-2008 was considerably high and the rate for out-of-pocket payments is nearly the same or greater than the rate for total health expenditure. In 2008, urban and rural households in average pay 6.4% and 6.35% of their total expenditure on health services. Finally three categories of determinants of unfair and catastrophic payments by households were recognized in terms of households’ socio-economic status, equality/inequality conditions of the distribution of risk of financing, and economic aspects of health expenditure distribution.Conclusion: While extending the total share of government and prepayment sources of financing health services are considered as the simplest policy for limiting out-of-pocket payments, indicators and policies introduced in this study could also be considered important and useful for the development of health sector and easing access to health services, irrespective of health financing fairness

  17. Can a stochastic cusp catastrophe model explain housing market crashes?

    NARCIS (Netherlands)

    C. Diks; J. Wang

    2016-01-01

    Like stock market prices, housing prices often exhibit temporary booms and busts. A possible explanation for the observed abrupt changes is offered by the stochastic catastrophe model. This paper addresses the question whether the catastrophe model can describe and predict the dynamics of housing ma

  18. Grey forewarning and prediction for mine water inflowing catastrophe periods

    Institute of Scientific and Technical Information of China (English)

    MA Qi-hua; CAO Jian-jun

    2007-01-01

    Based on the theory of grey system, established GM (1, 1) grey catastrophe predict model for the first time in order to forecast the catastrophe periods of mine water inflowing (not the volume of water inflowing). After establishing the grey predict system of the catastrophe regularity of 10 month-average volume of water inflowing, the grey forewarning for mine water inflowing catastrophe periods was established which was used to analyze water disaster in -400 meter level of Wennan Colliery. Based on residual analysis,it shows that the result of grey predict system is almost close to the actual value. And the scene actual result also shows the reliability of prediction. Both the theoretical analysis and the scene actual result indicate feasibility and reliability of the method of grey catastrophe predict system.

  19. Threshold Concepts in Economics

    Science.gov (United States)

    Shanahan, Martin

    2016-01-01

    Purpose: The purpose of this paper is to examine threshold concepts in the context of teaching and learning first-year university economics. It outlines some of the arguments for using threshold concepts and provides examples using opportunity cost as an exemplar in economics. Design/ Methodology/Approach: The paper provides an overview of the…

  20. Manipulation of pain catastrophizing: An experimental study of healthy participants

    Directory of Open Access Journals (Sweden)

    Joel E Bialosky

    2008-11-01

    Full Text Available Joel E Bialosky1*, Adam T Hirsh2,3, Michael E Robinson2,3, Steven Z George1,3*1Department of Physical Therapy; 2Department of Clinical and Health Psychology; 3Center for Pain Research and Behavioral Health, University of Florida, Gainesville, Florida, USAAbstract: Pain catastrophizing is associated with the pain experience; however, causation has not been established. Studies which specifically manipulate catastrophizing are necessary to establish causation. The present study enrolled 100 healthy individuals. Participants were randomly assigned to repeat a positive, neutral, or one of three catastrophizing statements during a cold pressor task (CPT. Outcome measures of pain tolerance and pain intensity were recorded. No change was noted in catastrophizing immediately following the CPT (F(1,84 = 0.10, p = 0.75, partial η2 < 0.01 independent of group assignment (F(4,84 = 0.78, p = 0.54, partial η2 = 0.04. Pain tolerance (F(4 = 0.67, p = 0.62, partial η2 = 0.03 and pain intensity (F(4 = 0.73, p = 0.58, partial η2 = 0.03 did not differ by group. This study suggests catastrophizing may be difficult to manipulate through experimental pain procedures and repetition of specific catastrophizing statements was not sufficient to change levels of catastrophizing. Additionally, pain tolerance and pain intensity did not differ by group assignment. This study has implications for future studies attempting to experimentally manipulate pain catastrophizing.Keywords: pain, catastrophizing, experimental, cold pressor task, pain catastrophizing scale

  1. Applications of modelling historical catastrophic events with implications for catastrophe risk management

    Science.gov (United States)

    Sorby, A.; Grossi, P.; Pomonis, A.; Williams, C.; Nyst, M.; Onur, T.; Seneviratna, P.; Baca, A.

    2009-04-01

    The management of catastrophe risk is concerned with the quantification of financial losses, and their associated probabilities, for potential future catastrophes that might impact a region. Modelling of historical catastrophe events and, in particular, the potential consequences if a similar event were to occur at the present day can provide insight to help bridge the gap between what we know can happen from historical experience and what potential losses might be out there in the "universe" of potential catastrophes. The 1908 Messina Earthquake (and accompanying local tsunami) was one of the most destructive earthquakes to have occurred in Europe and by most accounts remains Europe's most fatal with over 70,000 casualties estimated. However, what would the potential consequences be, in terms of financial and human losses, if a similar earthquake were to occur at the present day? Exposures, building stock and populations can change over time and, therefore, the consequences of a similar earthquake at the present day may sensibly differ from those observed in 1908. The city of Messina has been reconstructed several times in its history, including following the 1908 earthquake and again following the Second World War. The 1908 earthquake prompted the introduction of the first seismic design regulations in Italy and since 1909 parts of the Messina and Calabria regions have been in the zones of highest seismic coefficient. Utilizing commercial catastrophe loss modelling technology - which combines the modelling of hazard, vulnerability, and financial losses on a database of property exposures - a modelled earthquake scenario of M7.2 in the Messina Straits region of Southern Italy is considered. This modelled earthquake is used to assess the potential consequences in terms of financial losses that an earthquake similar to the 1908 earthquake might have if it were to occur at the present day. Loss results are discussed in the context of applications for the financial

  2. A preliminary assessment of asteroid shapes produced by impact disruption and re-creation: Application to the AIDA target.

    Science.gov (United States)

    Barnouin, Olivier; Michel, Patrick; Richardson, Derek

    2016-04-01

    In order to understand the origin of the 65803 Didymos, the target of the Asteroid Impact and Deflection Assessment mission, and gain insights on the origin and evolution of the asteroid's162173 Ryugu and 101955 Bennu, we investigate systematically the shapes of all re-accumulated fragments produced by the catastrophic disruption of a parent body that is 1 km in diameter or larger. These new fragments eventually become new asteroids of the size that current sample-return missions plan to explore. We choose a range of impact conditions by varying the parent bodies' strength, size and porosity, and the velocity and size of the projectile. Impact conditions range from near the catastrophic threshold, usually designated by Q*, where half of the target's mass escapes, to far greater values above this threshold. Our numerical investigations of the catastrophic disruption, which are undertaken using an SPH hydrocode, include a model of fragmentation for porous materials. The gravitationally dominated phase of reaccumulation of our asteroids is computed using the N-body code pkdgrav. At sufficiently slow impact speeds in the N-body model, particles are permitted to stick, forming irregular, competent pieces that can gather into non-idealized rubble piles as a result of re-accumulation. Shape and spin information of re-accumulated bodies are thus preserved. Due to numerical expense, this first study uses what we call a hard-sphere model, rather than a soft-sphere spring and dashpot model. This latter model is more commonly used in granular flow simulations for which detailed treatment of the multicontact physics is needed, which is not the case here, and comes at the expense of much smaller timesteps. With the hard-sphere model, there are three supported collision outcomes for bonded aggregates: sticking on contact (to grow the aggregate); bouncing (computed for these generally non-central impacts); and fragmentation (wherein the particles involved become detached from

  3. Top Threshold Physics

    OpenAIRE

    Hoang, Andre H.

    2006-01-01

    Running a future Linear Collider at the top pair threshold allows for precise measurements of the mass, the widths and the couplings of the top quark. I give a nontechnical review on recent theoretical developments and the theory status in top threshold physics concerning QCD corrections and top quark finite lifetime and electroweak effects. I also discuss threshold physics in the context of measurements of the top Yukawa coupling from $e^+e^-\\to t\\bar t H$ and of squark pair production.

  4. Risk Measure and Premium Distribution on Catastrophe Reinsurance

    Institute of Scientific and Technical Information of China (English)

    XUN LI; WANG DE-HUI

    2012-01-01

    In this paper,we propose a new risk measure which is based on the Orlicz premium principle to characterize catastrophe risk premium.The intention is to develop a formulation strategy for Catastrophe Fund.The logarithm equivalent form of reinsurance premium is regarded as the retention of reinsurer,and the differential earnings between the reinsurance premium and the reinsurer's retention is accumulated as a part of Catastrophe Fund.We demonstrate that the aforementioned risk measure has some good properties,which are further confirmed by numerical simulations in R environment.

  5. Quantum threshold group signature

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

  6. Proteus - Geology, shape, and catastrophic destruction

    Science.gov (United States)

    Croft, Steven K.

    1992-01-01

    Least-squares fits to the two available limb profiles of Proteus yield a sphericity close to unity; the visual irregularity is due to a degree of surface roughness comparable to that of Hyperion and the smaller icy satellites. A network of streaks that can be interpreted as tectonic troughs cuts the surface of Proteus, and is organized concentrically around either one of the two nearly-coincident Proteus-Neptune of Pharos axes of symmetry. If the streaks are tectonic, they may be due to tidal stresses generated by a past change in Proteus' equilibrium orientation. The streaks may also be disruptive-stress fractures.

  7. Large-scale coastal impact induced by a catastrophic storm

    DEFF Research Database (Denmark)

    Fruergaard, Mikkel; Andersen, Thorbjørn Joest; Johannessen, Peter N;

    Catastrophic storms and storm surges induce rapid and substantial changes along sandy barrier coasts, potentially causing severe environmental and economic damage. Coastal impacts of modern storms are associated with washover deposition, dune erosion, barrier breaching, and coastline and shoreface...

  8. Catastrophic Events and Mass Extinctions: Impacts and Beyond

    Science.gov (United States)

    2000-01-01

    This volume contains extended abstracts that have been accepted for presentation at the conference on Catastrophic Events and Mass Extinctions: Impacts and Beyond, July 9-12, 2000, in Vienna, Austria.

  9. Pain frequency moderates the relationship between pain catastrophizing and pain

    Science.gov (United States)

    Kjøgx, Heidi; Zachariae, Robert; Pfeiffer-Jensen, Mogens; Kasch, Helge; Svensson, Peter; Jensen, Troels S.; Vase, Lene

    2014-01-01

    Background: Pain frequency has been shown to influence sensitization, psychological distress, and pain modulation. The present study examined if pain frequency moderates the relationship between pain catastrophizing and pain. Method: A non-clinical (247 students) and a clinical (223 pain patients) sample completed the Danish versions of the Pain Catastrophizing Scale (PCS), Beck Depression Inventory, and the State Trait Anxiety Inventory and rated pain intensity, unpleasantness and frequency. Results: In both samples, high pain frequency was found to moderate the association between pain catastrophizing and pain intensity, whereas low pain frequency did not. The psychometric properties and the factor structure of the Danish version of the PCS were confirmed. Conclusions: This is the first study to validate the Danish version of the PCS and to show that pain frequency moderates the relationship between pain catastrophizing and reported pain in both non-clinical and clinical populations. PMID:25646089

  10. Pain frequency moderates the relationship between pain catastrophizing and pain

    Directory of Open Access Journals (Sweden)

    Heidi eKjøgx

    2014-12-01

    Full Text Available Background Pain frequency has been shown to influence sensitization, psychological distress and pain modulation. The present study examined if pain frequency moderates the relationship between pain catastrophizing and pain. Method A non-clinical (247 students and a clinical (223 pain patients sample completed the Danish versions of the Pain Catastrophizing Scale, Beck Depression Inventory and the State Trait Anxiety Inventory and rated pain intensity, unpleasantness and frequency Results In both samples, high pain frequency was found to moderate the association between pain catastrophizing and pain intensity, whereas low pain frequency did not. The psychometric properties and the factor structure of the Danish version of the PCS were confirmed.Conclusions This is the first study to validate the Danish version of the PCS and to show that pain frequency moderates the relationship between pain catastrophizing and reported pain in both non-clinical and clinical populations.

  11. Chernobyl: Endless horror. Late effects of the reactor catastrophe

    International Nuclear Information System (INIS)

    Ten years after the accident, the people of Chernobyl are trying to live a normal life, but the problems resulting from the catastrophe have not been solved. Some of them are just starting to emerge. (orig.)

  12. Understanding disruptions in tokamaks

    International Nuclear Information System (INIS)

    This paper describes progress achieved since 2007 in understanding disruptions in tokamaks, when the effect of plasma current sharing with the wall was introduced into theory. As a result, the toroidal asymmetry of the plasma current measurements during vertical disruption event (VDE) on the Joint European Torus was explained. A new kind of plasma equilibria and mode coupling was introduced into theory, which can explain the duration of the external kink 1/1 mode during VDE. The paper presents first results of numerical simulations using a free boundary plasma model, relevant to disruptions.

  13. Navigating catastrophes: Local but not global optimisation allows for macro-economic navigation of crises

    Science.gov (United States)

    Harré, Michael S.

    2013-02-01

    Two aspects of modern economic theory have dominated the recent discussion on the state of the global economy: Crashes in financial markets and whether or not traditional notions of economic equilibrium have any validity. We have all seen the consequences of market crashes: plummeting share prices, businesses collapsing and considerable uncertainty throughout the global economy. This seems contrary to what might be expected of a system in equilibrium where growth dominates the relatively minor fluctuations in prices. Recent work from within economics as well as by physicists, psychologists and computational scientists has significantly improved our understanding of the more complex aspects of these systems. With this interdisciplinary approach in mind, a behavioural economics model of local optimisation is introduced and three general properties are proven. The first is that under very specific conditions local optimisation leads to a conventional macro-economic notion of a global equilibrium. The second is that if both global optimisation and economic growth are required then under very mild assumptions market catastrophes are an unavoidable consequence. Third, if only local optimisation and economic growth are required then there is sufficient parametric freedom for macro-economic policy makers to steer an economy around catastrophes without overtly disrupting local optimisation.

  14. Can we be prepared for the next accident or catastrophe?

    OpenAIRE

    Andersson, Annika

    2013-01-01

    Catastrophes and accidents (natural, technological, or man--‐made) have been subjected to scientific research from different disciplines and perspectives for a long time. Examples of these perspectives include community risk and vulnerability, human behaviour during crisis, fire behaviour and eco--‐system management, decision--‐making, communication, and collaboration issues. This paper deals with different perspectives of preparation and prevention in terms of accidents and catastrophes. The...

  15. Mathematical modeling of human behaviors during catastrophic events

    OpenAIRE

    Verdière, Nathalie; Lanza, Valentina; Charrier, Rodolphe; Provitolo, Damienne; Dubos-Paillard, Edwige; Bertelle, Cyrille; Aziz-Alaoui, Moulay

    2014-01-01

    In this paper, we introduce a new approach for modeling the human collective behaviors in the speci c scenario of a sudden catastrophe, this catastrophe can be natural (i.e. earthquake, tsunami) or technological (nuclear event). The novelty of our work is to propose a mathematical model taking into account di erent concurrent behaviors in such situation and to include the processes of transition from one behavior to the other during the event. Here, we focus more on the sequence of behaviors ...

  16. Climate change policy in a growing economy under catastrophic risks

    OpenAIRE

    Tsur, Yacov; Zemel, Amos

    2007-01-01

    Under risk of catastrophic climate change, the occurrence hazard is added to the social discount rate. As a result, the social discount rate (i) increases and (ii) turns endogenous to the global warming policy. The second effect bears profound policy implications that are magnifed by economic growth. In particular, it implies that green- house gases (GHG) emission should gradually be brought to a halt. Due to the public bad nature of the catastrophic risk, the second effect is ignored in a co...

  17. Some Aspects of the Economics of Catastrophe Risk Insurance

    OpenAIRE

    Gollier, Christian

    2005-01-01

    The ability to share risk efficiently in the economy is essential to welfare and growth. However, the increased frequency of natural catastrophes over the last decade has raised once again questions associated to the limits of insurability in a free-market economy, and to the relevance of public interventions on risk-sharing markets. In this paper, we explore the potential reasons for the lack of insurance specifically associated to catastrophe environmental risks. Our final aim is to link ea...

  18. Electron Vortex Production and Control Using Aberration Induced Diffraction Catastrophes

    Science.gov (United States)

    Petersen, T. C.; Weyland, M.; Paganin, D. M.; Simula, T. P.; Eastwood, S. A.; Morgan, M. J.

    2013-01-01

    An aberration corrected electron microscope is used to create electron diffraction catastrophes, containing arrays of intensity zeros threading vortex cores. Vortices are ascribed to these arrays using catastrophe theory, scalar diffraction integrals, and experimentally retrieved phase maps. From measured wave function phases, obtained using focal-series phase retrieval, the orbital angular momentum density is mapped for highly astigmatic electron probes. We observe vortex rings and topological reconnections of nodal lines by tracking the vortex cores using the retrieved phases.

  19. Pain Catastrophizing Correlates with Early Mild Traumatic Brain Injury Outcome.

    Science.gov (United States)

    Chaput, Geneviève; Lajoie, Susanne P; Naismith, Laura M; Lavigne, Gilles

    2016-01-01

    Background. Identifying which patients are most likely to be at risk of chronic pain and other postconcussion symptoms following mild traumatic brain injury (MTBI) is a difficult clinical challenge. Objectives. To examine the relationship between pain catastrophizing, defined as the exaggerated negative appraisal of a pain experience, and early MTBI outcome. Methods. This cross-sectional design included 58 patients diagnosed with a MTBI. In addition to medical chart review, postconcussion symptoms were assessed by self-report at 1 month (Time 1) and 8 weeks (Time 2) after MTBI. Pain severity, psychological distress, level of functionality, and pain catastrophizing were measured by self-report at Time 2. Results. The pain catastrophizing subscales of rumination, magnification, and helplessness were significantly correlated with pain severity (r = .31 to .44), number of postconcussion symptoms reported (r = .35 to .45), psychological distress (r = .57 to .67), and level of functionality (r = -.43 to -.29). Pain catastrophizing scores were significantly higher for patients deemed to be at high risk of postconcussion syndrome (6 or more symptoms reported at both Time 1 and Time 2). Conclusions. Higher levels of pain catastrophizing were related to adverse early MTBI outcomes. The early detection of pain catastrophizing may facilitate goal-oriented interventions to prevent or minimize the development of chronic pain and other postconcussion symptoms. PMID:27445604

  20. Pain Catastrophizing Correlates with Early Mild Traumatic Brain Injury Outcome

    Directory of Open Access Journals (Sweden)

    Geneviève Chaput

    2016-01-01

    Full Text Available Background. Identifying which patients are most likely to be at risk of chronic pain and other postconcussion symptoms following mild traumatic brain injury (MTBI is a difficult clinical challenge. Objectives. To examine the relationship between pain catastrophizing, defined as the exaggerated negative appraisal of a pain experience, and early MTBI outcome. Methods. This cross-sectional design included 58 patients diagnosed with a MTBI. In addition to medical chart review, postconcussion symptoms were assessed by self-report at 1 month (Time 1 and 8 weeks (Time 2 after MTBI. Pain severity, psychological distress, level of functionality, and pain catastrophizing were measured by self-report at Time 2. Results. The pain catastrophizing subscales of rumination, magnification, and helplessness were significantly correlated with pain severity (r=.31 to .44, number of postconcussion symptoms reported (r=.35 to .45, psychological distress (r=.57 to .67, and level of functionality (r=-.43 to -.29. Pain catastrophizing scores were significantly higher for patients deemed to be at high risk of postconcussion syndrome (6 or more symptoms reported at both Time 1 and Time 2. Conclusions. Higher levels of pain catastrophizing were related to adverse early MTBI outcomes. The early detection of pain catastrophizing may facilitate goal-oriented interventions to prevent or minimize the development of chronic pain and other postconcussion symptoms.

  1. Search and Disrupt

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders

    This paper analyzes how external search is affected by strategic interest alignment among knowledge sources. I focus on misalignment arising from the heterogeneous effects of disruptive technologies by analyzing the influence of incumbents on 2,855 non-incumbents? external knowledge search efforts....... The efforts most likely to solve innovation problems obtained funding from the European Commission?s 7th Framework Program (2007-2013). The results show that involving incumbents improves search in complementary technologies, while demoting it when strategic interests are misaligned in disruptive...... technologies. However, incumbent sources engaged in capability reconfiguration to accommodate disruption improve search efforts in disruptive technologies. The paper concludes that the value of external sources is contingent on more than their knowledge. Specifically, interdependence of sources in search gives...

  2. Polynomial threshold functions and Boolean threshold circuits

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.

    2013-01-01

    secondary interest. We show that PTFs on general Boolean domains are tightly connected to depth two threshold circuits. Our main results in regard to this connection are: PTFs of polynomial length and polynomial degree compute exactly the functions computed by THRMAJ circuits. An exponential length lower...... bound for PTFs that holds regardless of degree, thereby extending known lower bounds for THRMAJ circuits. We generalize two-party unbounded error communication complexity to the multi-party number-on-the-forehead setting, and show that communication lower bounds for 3-player protocols would yield size...... lower bounds for THRTHR circuits. We obtain several other results about PTFs. These include relationships between weight and degree of PTFs, and a degree lower bound for PTFs of constant length. We also consider a variant of PTFs over the max-plus algebra. We show that they are connected to PTFs over...

  3. Pion photoproduction near threshold

    International Nuclear Information System (INIS)

    A review of the high accuracy π+ threshold photoproduction cross-section determinations on deuterium and helium-3 is presented. These must be considered on the same footing as the data on electromagnetic observables, with reference to the important question of the description of the non nucleonic degrees of freedom in the nucleus. The π0 threshold photoproduction on very light nuclei which conveys information on the elementary nucleonic amplitudes in an energy region where one is sensitive to the break down of isospin symmetry as revealed by the π+-, π0 and the n, p mass splittings is discussed

  4. The race between cooperation and catastrophe

    International Nuclear Information System (INIS)

    If a nuclear weapon were detonated in London, or in any of the world's major cities, it would change our world forever. Beyond the horror and the immediate death, and the lives that would be shortened by radioactive fallout, the casualties could also include civil liberties, privacy, world confidence and the global economy. With so much at stake, our citizens have every reason to ask: 'Are we doing all we can to prevent a nuclear attack?' My emphatic answer is 'No, we are not.' We have, however, taken some important steps, including: - The Nunn-Lugar Cooperative Threat Reduction programme, working since 1991 to secure and destroy weapons and material in the former Soviet Union. This programme helped Kazakhstan, Ukraine and Belarus get rid of all their nuclear weapons, a historic achievement. - The G8 commitment launched three years ago to create and fund the Global Partnership Against the Spread of Weapons and Materials of Mass Destruction. - The recently launched US-Russian Global Threat Reduction Initiative to remove and secure high enriched uranium from research facilities around the globe. - The IAEA Nuclear Security Fund, launched to help Member States strengthen the security of nuclear material worldwide. - The commitment by Libya to give up its nuclear weapons programme following skilful diplomacy led by the United Kingdom and the United States of America, with important oversight by the IAEA. - The recent Bush-Putin summit, in which the President of the Russian Federation and the President of the USA each made a personal commitment to enhance and accelerate efforts to secure nuclear weapons and nuclear material worldwide. These are all indispensable steps for global security, but we have miles to go before we sleep. We must remove roadblocks, we must provide more resources, we must convert pledges to programmes and words to deeds. We must develop a global partnership against catastrophic terrorism that is effective, focused and truly global. This includes

  5. Predicting Predictable about Natural Catastrophic Extremes

    Science.gov (United States)

    Kossobokov, Vladimir

    2015-04-01

    predictable, but not the exact size, site, date, and probability of an extreme catastrophe. This, apparently natural concept, is illustrated by application to seismic extremes that show how understanding by modeling the complexity of non-linear dynamics of hierarchically organized systems of blocks-and-faults has led to reliable methodologies of neo-deterministic seismic hazard analysis and intermediate-term middle- to narrow-range earthquake prediction algorithms tested in real-time applications over the last decades.

  6. From Catastrophizing to Recovery: a pilot study of a single-session treatment for pain catastrophizing

    Directory of Open Access Journals (Sweden)

    Darnall BD

    2014-04-01

    Full Text Available Beth D Darnall, John A Sturgeon, Ming-Chih Kao, Jennifer M Hah, Sean C MackeyDivision of Pain Medicine, Stanford Systems Neuroscience and Pain Laboratory, Stanford University School of Medicine, Palo Alto, CA, USABackground: Pain catastrophizing (PC – a pattern of negative cognitive-emotional responses to real or anticipated pain – maintains chronic pain and undermines medical treatments. Standard PC treatment involves multiple sessions of cognitive behavioral therapy. To provide efficient treatment, we developed a single-session, 2-hour class that solely treats PC entitled “From Catastrophizing to Recovery”[FCR].Objectives: To determine 1 feasibility of FCR; 2 participant ratings for acceptability, understandability, satisfaction, and likelihood to use the information learned; and 3 preliminary efficacy of FCR for reducing PC.Design and methods: Uncontrolled prospective pilot trial with a retrospective chart and database review component. Seventy-six patients receiving care at an outpatient pain clinic (the Stanford Pain Management Center attended the class as free treatment and 70 attendees completed and returned an anonymous survey immediately post-class. The Pain Catastrophizing Scale (PCS was administered at class check-in (baseline and at 2, and 4 weeks post-treatment. Within subjects repeated measures analysis of variance (ANOVA with Student's t-test contrasts were used to compare scores across time points.Results: All attendees who completed a baseline PCS were included as study participants (N=57; F=82%; mean age =50.2 years; PCS was completed by 46 participants at week 2 and 35 participants at week 4. Participants had significantly reduced PC at both time points (P<0001 and large effect sizes were found (Cohen's d=0.85 and d=1.15.Conclusion: Preliminary data suggest that FCR is an acceptable and effective treatment for PC. Larger, controlled studies of longer duration are needed to determine durability of response, factors

  7. Disruption prediction at JET

    International Nuclear Information System (INIS)

    The sudden loss of the plasma magnetic confinement, known as disruption, is one of the major issue in a nuclear fusion machine as JET (Joint European Torus). Disruptions pose very serious problems to the safety of the machine. The energy stored in the plasma is released to the machine structure in few milliseconds resulting in forces that at JET reach several Mega Newtons. The problem is even more severe in the nuclear fusion power station where the forces are in the order of one hundred Mega Newtons. The events that occur during a disruption are still not well understood even if some mechanisms that can lead to a disruption have been identified and can be used to predict them. Unfortunately it is always a combination of these events that generates a disruption and therefore it is not possible to use simple algorithms to predict it. This thesis analyses the possibility of using neural network algorithms to predict plasma disruptions in real time. This involves the determination of plasma parameters every few milliseconds. A plasma boundary reconstruction algorithm, XLOC, has been developed in collaboration with Dr. D. O'Brien and Dr. J. Ellis capable of determining the plasma wall/distance every 2 milliseconds. The XLOC output has been used to develop a multilayer perceptron network to determine plasma parameters as li and qψ with which a machine operational space has been experimentally defined. If the limits of this operational space are breached the disruption probability increases considerably. Another approach for prediction disruptions is to use neural network classification methods to define the JET operational space. Two methods have been studied. The first method uses a multilayer perceptron network with softmax activation function for the output layer. This method can be used for classifying the input patterns in various classes. In this case the plasma input patterns have been divided between disrupting and safe patterns, giving the possibility of

  8. Elaborating on Threshold Concepts

    Science.gov (United States)

    Rountree, Janet; Robins, Anthony; Rountree, Nathan

    2013-01-01

    We propose an expanded definition of Threshold Concepts (TCs) that requires the successful acquisition and internalisation not only of knowledge, but also its practical elaboration in the domains of applied strategies and mental models. This richer definition allows us to clarify the relationship between TCs and Fundamental Ideas, and to account…

  9. Setting Graduation Rate Thresholds.

    Science.gov (United States)

    Underwood, David G.; Rieck, James R.

    1999-01-01

    Reviews the college completion/graduation rate thresholds developed by several states and discusses advantages and disadvantages of several statistical approaches, including use of the one standard deviation lower bound method, the logit prediction bound method, the linear regression method, and the logistic regression method. (DB)

  10. Catastrophic destabilization of tunnel under rocks slipping in faultage

    Institute of Scientific and Technical Information of China (English)

    LIU Hai-qing; WANG Xue-qing; YUAN Jing

    2008-01-01

    The model of catastrophic destabilization of tunnel under rock slipping in fault zone based on catastrophic theory and the potential function of fault movement were presented. On the basis of the results above, through Taylor series expansion of the equation of equilibrium surface, its standard form was obtained. Analysis show that catastrophic destabilization of tunnel will occur only when stiffness ratio between elastic sector and strain weakening sector of soft rocks was larger than or equal to 1. On the other hand,sliding behavior and evolution path of fault were directly affected by exogenous process,and it was a major extraneous factor which leads to catastrophic destabilization of tunnel.In the condition of system catastrophe could be generated, if external forces vary from smaller to larger, firstly, fault sticks or creeps, and secondly, when external force equal to or larger than critical value, fault turns to slip suddenly. Inverse, if external forces vary from larger to smaller, fault smoothly slips firstly, when external force equal to or smaller than critical value, and fault turns to stick or creep suddenly.

  11. Search and Disrupt

    DEFF Research Database (Denmark)

    Ørding Olsen, Anders

    Extant research on external knowledge search and open innovation assumes that collaborators are aligned in their strategic interests towards solving innovation problems. However, disruptive innovation is known to threaten the competitive advantage of incumbent firms, thereby creating a potential...... conflict of interest between these firms and their collaborators. This paper explores the extent to which strategic interests influence joint problem solving in both complementary and disruptive technologies by analyzing the effects of incumbent collaboration. The analysis disentangles inability and...... strategic intent to find that non-incumbents experience suppression of problem solving likelihood within disruptive technologies when incumbent collaborators are not strategically committed. The paper contributes to extant theory by showing the influence of firms’ underlying strategic interests on their...

  12. Interruptions disrupt reading comprehension.

    Science.gov (United States)

    Foroughi, Cyrus K; Werner, Nicole E; Barragán, Daniela; Boehm-Davis, Deborah A

    2015-06-01

    Previous research suggests that being interrupted while reading a text does not disrupt the later recognition or recall of information from that text. This research is used as support for Ericsson and Kintsch's (1995) long-term working memory (LT-WM) theory, which posits that disruptions while reading (e.g., interruptions) do not impair subsequent text comprehension. However, to fully comprehend a text, individuals may need to do more than recognize or recall information that has been presented in the text at a later time. Reading comprehension often requires individuals to connect and synthesize information across a text (e.g., successfully identifying complex topics such as themes and tones) and not just make a familiarity-based decision (i.e., recognition). The goal for this study was to determine whether interruptions while reading disrupt reading comprehension when the questions assessing comprehension require participants to connect and synthesize information across the passage. In Experiment 1, interruptions disrupted reading comprehension. In Experiment 2, interruptions disrupted reading comprehension but not recognition of information from the text. In Experiment 3, the addition of a 15-s time-out prior to the interruption successfully removed these negative effects. These data suggest that the time it takes to process the information needed to successfully comprehend text when reading is greater than that required for recognition. Any interference (e.g., an interruption) that occurs during the comprehension process may disrupt reading comprehension. This evidence supports the need for transient activation of information in working memory for successful text comprehension and does not support LT-WM theory. PMID:25867225

  13. Catastrophic disasters and the design of disaster medical care systems.

    Science.gov (United States)

    Mahoney, L E; Reutershan, T P

    1987-09-01

    The National Disaster Medical System (NDMS) is aimed at medical care needs resulting from catastrophic earthquakes, which may cause thousands of deaths and injuries. Other geophysical events may cause great mortality, but leave few injured survivors. Weather incidents, technological disasters, and common mass casualty incidents cause much less mortality and morbidity. Catastrophic disasters overwhelm the local medical care system. Supplemental care is provided by disaster relief forces; this care should be adapted to prevalent types of injuries. Most care should be provided at the disaster scene through supplemental medical facilities, while some can be provided by evacuating patients to distant hospitals. Medical response teams capable of stabilizing, sorting, and holding victims should staff supplemental medical facilities. The NDMS program includes hospital facilities, evacuation assets, and medical response teams. The structure and capabilities of these elements are determined by the medical care needs of the catastrophic disaster situation. PMID:3631673

  14. Gravothermal Catastrophe: the dynamical stability of a fluid model

    CERN Document Server

    Sormani, M C

    2013-01-01

    A re-investigation of the gravothermal catastrophe is presented. By means of a linear perturbation analysis, we study the dynamical stability of a spherical self-gravitating isothermal fluid of finite volume and find that the conditions for the onset of the gravothermal catastrophe, under different external conditions, coincide with those obtained from thermodynamical arguments. This suggests that the gravothermal catastrophe may reduce to Jeans instability, rediscovered in an inhomogeneous framework. We find normal modes and frequencies for the fluid system and show that instability develops on the dynamical time scale. We then discuss several related issues. In particular: (1) For perturbations at constant total energy and constant volume, we introduce a simple heuristic term in the energy budget to mimic the role of binaries. (2) We outline the analysis of the two-component case and show how linear perturbation analysis can be carried out also in this more complex context in a relatively straightforward wa...

  15. Dynamical systems V bifurcation theory and catastrophe theory

    CERN Document Server

    1994-01-01

    Bifurcation theory and catastrophe theory are two of the best known areas within the field of dynamical systems. Both are studies of smooth systems, focusing on properties that seem to be manifestly non-smooth. Bifurcation theory is concerned with the sudden changes that occur in a system when one or more parameters are varied. Examples of such are familiar to students of differential equations, from phase portraits. Moreover, understanding the bifurcations of the differential equations that describe real physical systems provides important information about the behavior of the systems. Catastrophe theory became quite famous during the 1970's, mostly because of the sensation caused by the usually less than rigorous applications of its principal ideas to "hot topics", such as the characterization of personalities and the difference between a "genius" and a "maniac". Catastrophe theory is accurately described as singularity theory and its (genuine) applications. The authors of this book, the first printing of w...

  16. Catastrophic ice lake collapse in Aram Chaos, Mars

    CERN Document Server

    Roda, Manuel; Zegers, Tanja E; Oosthoek, Jelmer H P

    2014-01-01

    Hesperian chaotic terrains have been recognized as the source of outflow channels formed by catastrophic outflows. Four main scenarios have been proposed for the formation of chaotic terrains that involve different amounts of water and single or multiple outflow events. Here, we test these scenarios with morphological and structural analyses of imagery and elevation data for Aram Chaos in conjunction with numerical modeling of the morphological evolution of the catastrophic carving of the outflow valley. The morphological and geological analyses of Aram Chaos suggest large-scale collapse and subsidence (1500 m) of the entire area, which is consistent with a massive expulsion of liquid water from the subsurface in one single event. The combined observations suggest a complex process starting with the outflow of water from two small channels, followed by continuous groundwater sapping and headward erosion and ending with a catastrophic lake rim collapse and carving of the Aram Valley, which is synchronous with ...

  17. Grossman's Missing Health Threshold

    OpenAIRE

    Titus J. Galama; Arie Kapteyn

    2009-01-01

    The authors present a generalized solution to Grossman's model of health capital (1972), relaxing the widely used assumption that individuals can adjust their health stock instantaneously to an "optimal" level without adjustment costs. The Grossman model then predicts the existence of a health threshold above which individuals do not demand medical care. Their generalized solution addresses a significant criticism: the model's prediction that health and medical care are positively related is ...

  18. Elaborating on threshold concepts

    Science.gov (United States)

    Rountree, Janet; Robins, Anthony; Rountree, Nathan

    2013-09-01

    We propose an expanded definition of Threshold Concepts (TCs) that requires the successful acquisition and internalisation not only of knowledge, but also its practical elaboration in the domains of applied strategies and mental models. This richer definition allows us to clarify the relationship between TCs and Fundamental Ideas, and to account for both the important and the problematic characteristics of TCs in terms of the Knowledge/Strategies/Mental Models Framework defined in previous work.

  19. Efficient Threshold Signature Scheme

    Directory of Open Access Journals (Sweden)

    Sattar J Aboud

    2012-01-01

    Full Text Available In this paper, we introduce a new threshold signature RSA-typed scheme. The proposed scheme has the characteristics of un-forgeable and robustness in random oracle model. Also, signature generation and verification is entirely non-interactive. In addition, the length of the entity signature participate is restricted by a steady times of the length of the RSA signature modulus. Also, the signing process of the proposed scheme is more efficient in terms of time complexity and interaction.

  20. Vibration intensity difference thresholds

    OpenAIRE

    Forta, Nazim Gizem

    2009-01-01

    The intensity difference threshold is defined as ‘the difference in the intensity of two stimuli which is just sufficient for their difference to be detected’. The aim of this thesis is to advance understanding of the perception of vibration intensity differences in humans. In addition to increasing understanding of the tactile senses, knowledge of difference perception could inform various applications such as the optimisation of the vibration characteristics of vehicles and ...

  1. Application of Catastrophe Theory in 3D Seismic Data Interpretation of Coal Mine

    Institute of Scientific and Technical Information of China (English)

    ZHAO Mu-hua; YANG Wen-qiang; CUI Hui-xia

    2005-01-01

    In order to detect fault exactly and quickly, cusp catastrophe theory is used to interpret 3D coal seismic data in this paper. By establishing a cusp model, seismic signal is transformed into standard form of cusp catastrophe and catastrophe parameters, including time-domain catastrophe potential, time-domain catastrophe time, frequency-domain catastrophe potential and frequency- domain degree, are calculated. Catastrophe theory is used in 3D seismic structural interpretation in coal mine. The results show that the position of abnormality of the catastrophe parameter profile or curve is related to the location of fault, and the cusp catastrophe theory is effective to automatically pick up geology information and improve the interpretation precision in 3D seismic data.

  2. Crisis Management Aspects of Bam Catastrophic Earthquake: Review Article

    OpenAIRE

    Homayoun Sadeghi-Bazargani; Saber Azami-Aghdash; Abdolhassan Kazemi; Behrad Ziapour

    2015-01-01

    Background: Bam earthquake was the most catastrophic natural disasters in recent years. The aim of this study was to review different aspects of crisis manage­ment during and after the catastrophic earthquake in Bam City, Iran.Methods: Data needed for this systematic review were collected through search­ing PubMed, EMBASE and SID databases, for the period from 2003 to 2011. Keywords included earthquake, Iran and Bam earthquake. The data were summarized and were analyzed using Content Analysis...

  3. Catastrophic antiphospholipid syndrome presenting as fever of unknown origin

    Directory of Open Access Journals (Sweden)

    Fatma I Al-Beladi

    2012-01-01

    Full Text Available Antiphospholipid syndrome is characterized by the presence of antiphospholipid antibodies with characteristic clinical manifestation, which include venous, arterial thrombosis, thrombotic microangiopathy, and recurrent fetal loss. The syndrome can be secondary to many causes including systemic lupus erythematosus (SLE or "primary" antiphospholipid syndrome (APLS. We report a case of a man with catastrophic antiphospholipid syndrome (CAPS, which occurs when three or more organ systems are affected by thrombosis in less than a week. Catastrophic antiphospholipid syndrome is uncommon but often fatal. The patient received a successful treatment that controlled this disease and included intravenous heparin, antiplatelet, intravenous corticosteroid, and plasmapheresis.

  4. COLLISIONAL STRIPPING AND DISRUPTION OF SUPER-EARTHS

    International Nuclear Information System (INIS)

    The final stage of planet formation is dominated by collisions between planetary embryos. The dynamics of this stage determine the orbital configuration and the mass and composition of planets in the system. In the solar system, late giant impacts have been proposed for Mercury, Earth, Mars, and Pluto. In the case of Mercury, this giant impact may have significantly altered the bulk composition of the planet. Here we present the results of smoothed particle hydrodynamics simulations of high-velocity (up to ∼5v esc) collisions between 1 and 10 M + planets of initially terrestrial composition to investigate the end stages of formation of extrasolar super-Earths. As found in previous simulations of collisions between smaller bodies, when collision energies exceed simple merging, giant impacts are divided into two regimes: (1) disruption and (2) hit-and-run (a grazing inelastic collision and projectile escape). Disruption occurs when the impact parameter is near zero, when the projectile mass is small compared to the target, or at extremely high velocities. In the disruption regime, we derive the criteria for catastrophic disruption (when half the total colliding mass is lost), the transition energy between accretion and erosion, and a scaling law for the change in bulk composition (iron-to-silicate ratio) resulting from collisional stripping of a mantle.

  5. Study of runaway current generation following disruptions in KSTAR

    International Nuclear Information System (INIS)

    The high fraction of runaway current conversion following disruptions has an important effect on the first wall for next-generation tokamaks. Because of the potentially severe consequences of a large full current runaway beam on the first wall in an unmitigated disruption, runaway suppression is given a high priority. The behavior of runaway currents both in spontaneous disruptions and in D2 massive gas injection (MGI) shutdown experiments is investigated in the KSTAR tokamak. The experiments in KSTAR show that the toroidal magnetic field threshold, BT >2 T, for runaway generation is not absolute. A high fraction of runaway current conversion following spontaneous disruptions is observed at a much lower toroidal magnetic field of BT = 1.3 T. A dedicated fast valve for high-pressure gas injection with 39.7 bar is developed for the study of disruptions. A study of runaway current parameters shows that the conversion efficiency of pre-disruptive plasma currents into runaway current can reach over 80% both in spontaneous disruptions and in D2 MGI shutdown experiments in KSTAR. (paper)

  6. Threshold laws for multiparticle fragmentation

    International Nuclear Information System (INIS)

    The threshold behavior of the cross section for break-up of an atomic particle into N charged fragments is described by power law, σfr ∼ Eμ, where E is the energy excess above the threshold. The threshold index μ reflects the dynamics of long-range Coulomb correlation. The general features of the theory are discussed. The charge and mass dependence of the threshold index is analyzed for some particular systems. Refs. 13 (author)

  7. Hadron production near threshold

    Indian Academy of Sciences (India)

    B K Jain; N G Kelkar; K P Khmemchandani

    2006-04-01

    Final state interaction effects in → + and → 3He reactions are explored near threshold to study the sensitivity of the cross-sections to the potential and the scattering matrix. The final state scattering wave functions between and and and 3He are described rigorously. The production is described by the exchange of one pion and a -meson between two protons in the incident channel. The production is described by a two-step model, where in the first step a pion is produced. This pion then produces an by interacting with another nucleon.

  8. Unstable Particles near Threshold

    CERN Document Server

    Chway, Dongjin; Kim, Hyung Do

    2015-01-01

    We explore physics of unstable particles when mother particle mass is around the sum of its daughter particle masses. In this case, the conventional wave function renormalization factor is ill-defined. We propose a simple resolution of the threshold singularity problem which still allows the use of narrow width approximation by defining branching ratio in terms of spectral density. The resonance peak and shape is different for different decay channels and no single decay width can be assigned to the unstable particles. Non-exponential decay happens in all time scales.

  9. 7 CFR 402.4 - Catastrophic Risk Protection Endorsement Provisions.

    Science.gov (United States)

    2010-01-01

    ... history program (7 CFR part 400, subpart G) or for crops not included under 7 CFR part 400, subpart G, the... Endorsement: (1) The Common Crop Insurance Policy (7 CFR 457.8) and crop provisions; (2) The Group Risk Plan... 7 Agriculture 6 2010-01-01 2010-01-01 false Catastrophic Risk Protection Endorsement...

  10. On the governance of global and catastrophic risks

    DEFF Research Database (Denmark)

    Faber, Michael Havbro

    2011-01-01

    The focus of the present paper regards the identification and treatment of critical issues in the process of societal decision making concerning management of global and catastrophic risks. Taking basis in recent works by the author, the paper in particular addresses: 1) Which are the most relevant...

  11. ATR Prohibits Replication Catastrophe by Preventing Global Exhaustion of RPA

    DEFF Research Database (Denmark)

    Toledo Lazaro, Luis Ignacio; Altmeyer, Matthias; Rask, Maj-Britt;

    2013-01-01

    origin firing generates an excess of single-stranded DNA that exhausts the nuclear pool of RPA. Partial reduction of RPA accelerated fork breakage, and forced elevation of RPA was sufficient to delay such "replication catastrophe" even in the absence of ATR activity. Conversely, unscheduled origin firing...

  12. Self-Organized Patchiness and Catastrophic Shifts in Ecosystems

    NARCIS (Netherlands)

    Rietkerk, Max; Dekker, Stefan C.; Ruiter, Peter C. de; Koppel, Johan van de

    2004-01-01

    Unexpected sudden catastrophic shifts may occur in ecosystems, with concomitant losses or gains of ecological and economic resources. Such shifts have been theoretically attributed to positive feedback and bistability of ecosystem states. However, verifications and predictive power with respect to c

  13. Self-organized patchiness and catastrophic shifts in ecosystems

    NARCIS (Netherlands)

    Rietkerk, M.; Dekker, S.C.; de Ruiter, P.C.; Van de Koppel, J.

    2004-01-01

    Unexpected sudden catastrophic shifts may occur in ecosystems, with concomitant losses or gains of ecological and economic resources. Such shifts have been theoretically attributed to positive feedback and bistability of ecosystem states. However, verifications and predictive power with respect to c

  14. Early warning signals also precede non-catastrophic transitions

    NARCIS (Netherlands)

    Kefi, S.; Dakos, V.; Scheffer, M.; Nes, E.H. van; Rietkerk, M.

    2013-01-01

    Ecosystem responses to external changes can surprise us by their abruptness and irreversibility. Models have helped identifying indicators of impending catastrophic shifts, referred to as ‘generic early warning signals’. These indicators are linked to a phenomenon known as ‘critical slowing down’ wh

  15. Three Solvable Matrix Models of a Quantum Catastrophe

    Czech Academy of Sciences Publication Activity Database

    Levai, G.; Růžička, František; Znojil, Miloslav

    2014-01-01

    Roč. 53, č. 9 (2014), s. 2875-2890. ISSN 0020-7748 Institutional support: RVO:61389005 Keywords : quantum theory * PT symmetry * Finite-dimensional non-Hermitian Hamiltonians * exceptional-point localization * quantum theory of catastrophes * methods of computer algebra Subject RIV: BE - Theoretical Physics Impact factor: 1.184, year: 2014

  16. Training and Practice in Trauma, Catastrophes, and Disaster Counseling

    Science.gov (United States)

    Bowman, Sharon L.; Roysircar, Gargi

    2011-01-01

    Trauma-related assistance in response to disasters or catastrophes is needed locally, regionally, nationally, and internationally, and the authors argue that there is a necessity for counseling psychologists and counseling psychology programs to incorporate it into their prevention, training, and social justice repertoire. Counseling psychologists…

  17. Endocrine disrupting compounds

    DEFF Research Database (Denmark)

    Bøgh, I B; Christensen, P; Dantzer, V;

    2001-01-01

    With the growing concern that environmental chemicals might impair human and animal fertility, it is important to investigate the possible influence of these substances on sexual differentiation and genital development of mammals. Many of these substances are suspected to interfere with endocrine...... of alkylphenols, these are disseminated in the environment with sewage sludge, and domestic animals and humans are likely to be exposed via the food chain. Using the pig as an in vivo model, we studied the effect of intrauterine exposure to tertiary octylphenol (OP) on essential reproductive...... usefulness of in vivo animal or embryo models for the evaluation of possible consequences of human exposure to endocrine disrupting compounds is discussed. Furthermore, possible consequences of exposure to endocrine disrupting compounds for the embryo transfer industry are addressed....

  18. Coloring geographical threshold graphs

    Energy Technology Data Exchange (ETDEWEB)

    Bradonjic, Milan [Los Alamos National Laboratory; Percus, Allon [Los Alamos National Laboratory; Muller, Tobias [EINDHOVEN UNIV. OF TECH

    2008-01-01

    We propose a coloring algorithm for sparse random graphs generated by the geographical threshold graph (GTG) model, a generalization of random geometric graphs (RGG). In a GTG, nodes are distributed in a Euclidean space, and edges are assigned according to a threshold function involving the distance between nodes as well as randomly chosen node weights. The motivation for analyzing this model is that many real networks (e.g., wireless networks, the Internet, etc.) need to be studied by using a 'richer' stochastic model (which in this case includes both a distance between nodes and weights on the nodes). Here, we analyze the GTG coloring algorithm together with the graph's clique number, showing formally that in spite of the differences in structure between GTG and RGG, the asymptotic behavior of the chromatic number is identical: {chi}1n 1n n / 1n n (1 + {omicron}(1)). Finally, we consider the leading corrections to this expression, again using the coloring algorithm and clique number to provide bounds on the chromatic number. We show that the gap between the lower and upper bound is within C 1n n / (1n 1n n){sup 2}, and specify the constant C.

  19. Community resilience and decision theory challenges for catastrophic events.

    Science.gov (United States)

    Cox, Louis Anthony

    2012-11-01

    Extreme and catastrophic events pose challenges for normative models of risk management decision making. They invite development of new methods and principles to complement existing normative decision and risk analysis. Because such events are rare, it is difficult to learn about them from experience. They can prompt both too little concern before the fact, and too much after. Emotionally charged and vivid outcomes promote probability neglect and distort risk perceptions. Aversion to acting on uncertain probabilities saps precautionary action; moral hazard distorts incentives to take care; imperfect learning and social adaptation (e.g., herd-following, group-think) complicate forecasting and coordination of individual behaviors and undermine prediction, preparation, and insurance of catastrophic events. Such difficulties raise substantial challenges for normative decision theories prescribing how catastrophe risks should be managed. This article summarizes challenges for catastrophic hazards with uncertain or unpredictable frequencies and severities, hard-to-envision and incompletely described decision alternatives and consequences, and individual responses that influence each other. Conceptual models and examples clarify where and why new methods are needed to complement traditional normative decision theories for individuals and groups. For example, prospective and retrospective preferences for risk management alternatives may conflict; procedures for combining individual beliefs or preferences can produce collective decisions that no one favors; and individual choices or behaviors in preparing for possible disasters may have no equilibrium. Recent ideas for building "disaster-resilient" communities can complement traditional normative decision theories, helping to meet the practical need for better ways to manage risks of extreme and catastrophic events. PMID:22967051

  20. Population resilience to catastrophic mortality events during early life stages.

    Science.gov (United States)

    Ohlberger, Jan; Langangen, Øystein

    2015-07-01

    Catastrophic mortality events that drastically reduce the abundance of a population or a particular life stage can have long-term ecological and economic effects, and are of great concern in species conservation and management. Severe die-offs may be caused by natural catastrophes such as disease outbreaks and extreme climates, or human-caused disturbances such as toxic spills. Forecasting potential impacts of such disturbances is difficult and highly uncertain due to unknown future conditions, including population status and environmental conditions at the time of impact. Here, we present a framework for quantifying the range of potential, population-level effects of catastrophic events based on a hindcasting approach. A dynamic population model with Bayesian parameter estimation is used to simulate the impact of severe (50-99%) mortality events during the early life stages of Northeast Arctic cod (Gadus morhua), an abundant marine fish population of high economic value. We quantify the impact of such die-offs in terms of subsequent changes in population biomass and harvest through direct comparison of simulated and historical trends, and estimate the duration of the impact as a measure of population resilience. Our results demonstrate strong resilience to catastrophic events that affect early life stages owing to density dependence in survival and a broad population age structure. Yet, while population recovery is. relatively fast, losses in harvest and economic value can be substantial. Future research efforts should focus on long-term and indirect effects via food web interactions in order to better understand the ecological and economic ramifications of catastrophic mortality events. PMID:26485960

  1. Coincident disruptive coloration

    OpenAIRE

    Cuthill, Innes C.; Székely, Aron

    2008-01-01

    Even if an animal matches its surroundings perfectly in colour and texture, any mismatch between the spatial phase of its pattern and that of the background, or shadow created by its three-dimensional relief, is potentially revealing. Nevertheless, for camouflage to be fully broken, the shape must be recognizable. Disruptive coloration acts against object recognition by the use of high-contrast internal colour boundaries to break up shape and form. As well as the general outline, characterist...

  2. Schematically disruptive game design

    OpenAIRE

    Howell, Peter

    2011-01-01

    Many games focus their resources at satiating player ‘needs’, and meeting perceived expectations that players have of how games should behave and of what constitutes enjoyable, gratifying gameplay. This paper outlines an alternate position on game design – one which focuses on disrupting these expectations, on designing games that players cannot succeed in simply by relying on their pre-acquired gameplay experiences. A critique of current game design trends is offered, and possible future out...

  3. Search and Disrupt

    OpenAIRE

    Ørding Olsen, Anders

    2015-01-01

    This paper analyzes how external search is affected by strategic interest alignment among knowledge sources. I focus on misalignment arising from the heterogeneous effects of disruptive technologies by analyzing the influence of incumbents on 2,855 non-incumbents? external knowledge search efforts. The efforts most likely to solve innovation problems obtained funding from the European Commission?s 7th Framework Program (2007-2013). The results show that involving incumbents improv...

  4. Celibacy and Family Disruption

    OpenAIRE

    Emaletdinov B. M.

    2013-01-01

    Causes for celibacy, divorces and successful marriage are discussed in the article. Absence of true love and inability to build and keep it are the main reasons for family disruption. Amorousness, immature love and various forms of false or flawed love substitute the true feeling. It is caused by increased women’s independence, loss of mutual understanding and trust (due to infidelity or jealousy), incompatibility of characters or values. Celibacy is often conditioned by physical disability, ...

  5. Stability threshold approach for complex dynamical systems

    Science.gov (United States)

    Klinshov, Vladimir V.; Nekorkin, Vladimir I.; Kurths, Jürgen

    2016-01-01

    A new measure to characterize the stability of complex dynamical systems against large perturbations is suggested, the stability threshold (ST). It quantifies the magnitude of the weakest perturbation capable of disrupting the system and switch it to an undesired dynamical regime. In the phase space, the ST corresponds to the 'thinnest site' of the attraction basin and therefore indicates the most 'dangerous' direction of perturbations. We introduce a computational algorithm for quantification of the ST and demonstrate that the suggested approach is effective and provides important insights. The generality of the obtained results defines their vast potential for application in such fields as engineering, neuroscience, power grids, Earth science and many others where the robustness of complex systems is studied.

  6. Aerogel threshold Cherenkov counter

    International Nuclear Information System (INIS)

    The results of studying the SiO2 aerogel properties, used as radiator for the Cherenkov counters are presented. Brief data on the technology of preparing the aerogel samples and their optical characteristics are indicated. The formula binding the aerogel refractive index with its density with an account of light dispersion is analyzed. The results of the Cherenkov aerogel threshold counter testing on the charged particles beam within the pulse range of p = ∼ 0.4-2.5 eV/s are presented. The registration efficiency of pions with p ≥ 1 GeV/s constituted ∼ 97% and that of protons - ∼ 4% by the p ≤ 2.5 GeV/s

  7. 15 CFR 2301.10 - Applications resulting from catastrophic damage or emergency situations.

    Science.gov (United States)

    2010-01-01

    ... catastrophic damage or emergency situations. 2301.10 Section 2301.10 Commerce and Foreign Trade Regulations... Applications resulting from catastrophic damage or emergency situations. (a) An application may be filed with a... suffers catastrophic damage to the basic equipment essential to its continued operation as a result of...

  8. 78 FR 24310 - Study and Report to Congress on Natural Catastrophes and Insurance

    Science.gov (United States)

    2013-04-24

    ... Study and Report to Congress on Natural Catastrophes and Insurance AGENCY: Federal Insurance Office... market for natural catastrophe insurance in the United States.\\1\\ \\1\\ Public Law 112-141, Sec. 100247..., Attention: Study on Natural Catastrophes and Insurance, Room 1319 MT, Department of the Treasury,...

  9. Monolayer dispersion thresholds and threshold effect displayed by supported catalysts

    Institute of Scientific and Technical Information of China (English)

    Cun DENG

    2008-01-01

    The principle of spontaneous monolayer dis-persion holds that active components of many supported catalysts will disperse spontaneously onto the surface of the carrier. The monolayer dispersion threshold of the active component on the surface of the carrier can be measured by X-ray diffraction phase-quantitative extra-polation method, etc. By measuring the monolayer disper-sion threshold, beneficial information on the surface structure and dispersion of supported catalysts can be obtained, and the optimal preparative processing condi-tions of the catalysts can be chosen. The proportion of the active component of many supported catalysts can be optimized while its monolayer dispersion threshold is observed. Mutation values of many physicochemical properties of supported catalysts are related to monolayer dispersion thresholds; the threshold effect on catalysts is apparent, and the proposal regarding the threshold effect provides instruction for the research on catalysts.

  10. Disruption - Access cards service

    CERN Document Server

    2014-01-01

    We would like to inform you that between 10 November and 15 December 2014, the access cards service in Building 55 will be disrupted, as the GS Department has decided to improve the facilities for users of this building. During the work, you will find the registration, biometric registration and dosimeter exchange services on the second floor of Building 55 and the vehicle sticker service on the ground floor along with the access cards service. We thank you for your understanding and apologise for any inconvenience caused.

  11. Sustainable Disruption Management

    DEFF Research Database (Denmark)

    Vaaben, Bo Valdemar

    The world we live in is globalized. Goods are seldom made in the place where they are used or consumed, and we do increasingly travel to other countries for either business or pleasure. In our everyday lives we rely on well-functioning global transportations systems to continue the standard of li...... disruption management. The real-world results show considerable yearly savings of above 5.1 million USD for a medium size airline operating in European airspace, which is significantly affected by airspace congestions....

  12. Celibacy and Family Disruption

    Directory of Open Access Journals (Sweden)

    Emaletdinov B. M.

    2013-01-01

    Full Text Available Causes for celibacy, divorces and successful marriage are discussed in the article. Absence of true love and inability to build and keep it are the main reasons for family disruption. Amorousness, immature love and various forms of false or flawed love substitute the true feeling. It is caused by increased women’s independence, loss of mutual understanding and trust (due to infidelity or jealousy, incompatibility of characters or values. Celibacy is often conditioned by physical disability, revaluation of freedom and independence, huge requirements to partners, consumer attitude to life, infertility, alcohol and drug abuse, abnormalities in personality and sexuality.

  13. Acceptance of governmental communication in catastrophes and media coverage

    International Nuclear Information System (INIS)

    Technology policy - like every political field - has to deal with conflicts, in which different partial interests are negotiated. Technological catastrophes are based on past decisions in technology policy. From there specific problems of acceptance in catastrophes can only be understood according to this social and temporal context. Acceptance deficits of the government result from the insufficient consideration of the interests non-governmental actors express(ed) with regard to technological risk decisions. Therefore governmental risk and crisis communication should communicate the rationales underlying technology decisions, at the same time giving other actors the possibility of further negotiation. The media coverage plays an important role in this communication process. Following their own specific rules the media create a public sphere, in order to give different groups and institutions an orientation for their social acting. Governmental communication should not consider journalism as a transmission belt for its information policy - rather, in order to be effective, it should respect the specific journalistic conduct. (orig.)

  14. The Kychtym accident or the story of a secret catastrophe

    International Nuclear Information System (INIS)

    This paper analyses the causes, the circumstances and the environmental consequences of the Kychtym catastrophe (Ural, USSR) that occurred in September 29, 1957 in the fuel recycle plant of the Tcheliabinsk military-industrial complex. A brief description of the separation process and of the installations used is given to understand the conclusions of the inquiry carried out by Russian and foreign experts. The violent redox reaction between nitrates and acetates that occurred, was due to a lack of cooling in the fission products storage ponds. The catastrophe produced a huge strontium 90-rich radioactive cloud which led to a 9000 to 15000 km2 surface contamination. A comparison with the PUREX separation process used in France is given to evaluate the risk of such industrial accidents in French fuel recycle centers. (J.S.). 1 fig., 2 photos

  15. Intraoperative endobronchial rupture of pulmonary hydatid cyst: An airway catastrophe

    Directory of Open Access Journals (Sweden)

    Richa Gupta

    2013-01-01

    Full Text Available Hydatid cyst disease of lungs may not be symptomatic. It may present as spontaneous rupture in pleura or a bronchus. During spontaneous breathing, cyst content of endobronchially ruptured pulmonary hydatid cyst is mostly evacuated by coughing. However, during positive pressure ventilation such extruded fragments may lodge into smaller airway leading to an airway catastrophe. We present such accidental endobronchial rupture of pulmonary hydatid cyst during surgery, its prompt detection, and management by rigid bronchoscopy.

  16. Can a stochastic cusp catastrophe model explain stock market crashes?

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Vošvrda, Miloslav

    2009-01-01

    Roč. 33, č. 10 (2009), s. 1824-1836. ISSN 0165-1889 R&D Projects: GA ČR GD402/09/H045; GA ČR GA402/09/0965 Grant ostatní: GAUK(CZ) 46108 Institutional research plan: CEZ:AV0Z10750506 Keywords : Stochastic cusp catastrophe * Bifurcations * Singularity * Nonlinear dynamics * Stock market crash Subject RIV: AH - Economics Impact factor: 1.097, year: 2009

  17. The Risk and Duration of Catastrophic Health Care Expenditures

    OpenAIRE

    Feenberg, Daniel; Skinner, Jonathan

    1992-01-01

    Catastrophic medical expenses are an important economic risk facing the elderly. Little is known about the persistence of such out-of-pocket medical costs. We measure the time-series property of medical costs using information on medical deductions from a panel of tax returns. During the period of analysis, 1968-73, taxpayers could deduct medical expenses above 3 percent of income. We correct for the resulting censoring bias using multivariate Tobit estimated with a variant of the smoothed si...

  18. Bank strategies in catastrophe settings: empirical evidence and policy suggestions

    OpenAIRE

    Leonardo Becchetti; Stefano Castriota; Pierluigi Conzo

    2012-01-01

    The poor in developing countries are the most exposed to natural catastrophes and microfinance organizations may potentially ease their economic recovery. Yet, no evidence on MFIs strategies after natural disasters exists. We aim to fill this gap by building adataset which merges bank records of loans, issued before and after the 2004 Tsunami by a Sri Lankan MFI recapitalized by Western donors, with detailed survey data on the corresponding borrowers. Evidence of effective post-calamity inter...

  19. Iatrogenic diaphragmatic hernia in infants: Potentially catastrophic when overlooked

    Directory of Open Access Journals (Sweden)

    Yousef El-Gohary

    2014-11-01

    Full Text Available Acquired diaphragmatic hernias are a rare occurrence. They can result from blunt, penetrating or inadvertent iatrogenic injury. When overlooked they can potentially be catastrophic. We report a case of iatrogenic diaphragmatic hernia in a six-month old infant presenting with acute respiratory distress as a result of strangulated bowel herniating into the left hemithorax caused from a traumatic chest tube insertion in the neonatal period.

  20. Book review: Global NATO and the catastrophic failure in Libya

    OpenAIRE

    von Weitershausen, Inez

    2013-01-01

    "Global NATO and the Catastrophic Failure in Libya." Horace Campbell. Monthly Review Press. March 2013. --- Horace Campbell investigates the political and economic crises of the early twenty-first century through the prism of NATO’s intervention in Libya. He traces the origins of the conflict, situates it in the broader context of the Arab Spring uprisings, and explains the expanded role of a post-Cold War NATO. This military organization is the instrument through which the capitalist cla...

  1. Pricing Excess-of-loss Reinsurance Contracts Against Catastrophic Loss

    OpenAIRE

    J. David Cummins; Lewis, Christopher M.; Phillips, Richard D.

    1998-01-01

    This paper develops a pricing methodology and pricing estimates for the proposed Federal excess-of- loss (XOL) catastrophe reinsurance contracts. The contracts, proposed by the Clinton Administration, would provide per-occurrence excess-of-loss reinsurance coverage to private insurers and reinsurers, where both the coverage layer and the fixed payout of the contract are based on insurance industry losses, not company losses. In financial terms, the Federal government would be selling earthqua...

  2. An illustrative 'plug & play' catastrophe model for groundwater flooding

    Science.gov (United States)

    Wang, Lei; Hillier, John; Royse, Kate; Lee, Tzu-Fung; O'Niel, Jullian; Kingdon, Andrew; Hughes, Andrew

    2013-04-01

    Economic losses from natural catastrophes are substantial; e.g., US130 billion in 2010. 'Catastrophe models' are stochastic event-set based models that simulate these risks and underpin their assessment in the insurance industry. Most catastrophe models are proprietary 'black boxes', which limit the level of user interaction, but new regulations (Solvency II) require firms to understand better the assumptions upon which the calculations ultimately rest. Part of this greater transparency requires constraining where uncertainty originates, perhaps by interchanging components provided by rival model vendors in 'plug and play' catastrophe models. The objective of this paper is to demonstrate a practical, accessible way in which this may be made possible. Specifically to do this the first, illustrative 'plug and play' model was created efficiently and effectively using OpenMI, a free 'open-source' model linking standard. In about 100 man-hours climate, groundwater flow, vulnerability, exposure and loss components were linked to output financial losses, i.e., occurrence exceedance probability (OEP) curves. Groundwater flooding near Marlborough (UK) is used for this proof of concept. Losses from this example dataset are small, about £3.8 million for a 33 yr OEP, but groundwater is an important compounding factor in UK flooding and this is the first, albeit rudimentary, attempt to probabilistically model loss for this hazard. Selected components are swopped, and losses calculated to show how insights into the origin of uncertainty can be gained. Crucially, OpenMI has the future potential to operate online and shield valuable data within components whilst allowing them to be swopped. So, it has the potential to underpin a secure, open-source, practical framework of use to the insurance industry.

  3. Market Integration for Shrimp and the Effect of Catastrophic Events

    OpenAIRE

    Harri, Ardian; Muhammad, Andrew; Jones, Keithly G.

    2010-01-01

    Seasonal unit-root testing and seasonal cointegration methods are employed to investigate the price transmission in U.S. shrimp markets. ARIMA and Vector Error Correction Models (VECM) are used to identify the effect of catastrophic events on individual price series in one region and the spillover effects in the price series for other regions. Results showed that a cointegrating relation exists between neighboring states, specifically between Alabama and Mississippi and Louisiana and Texas. C...

  4. Catastrophic Fault Recovery with Self-Reconfigurable Chips

    Science.gov (United States)

    Zheng, Will Hua; Marzwell, Neville I.; Chau, Savio N.

    2006-01-01

    Mission critical systems typically employ multi-string redundancy to cope with possible hardware failure. Such systems are only as fault tolerant as there are many redundant strings. Once a particular critical component exhausts its redundant spares, the multi-string architecture cannot tolerate any further hardware failure. This paper aims at addressing such catastrophic faults through the use of 'Self-Reconfigurable Chips' as a last resort effort to 'repair' a faulty critical component.

  5. Dynamic of gastroduodenal bleeding distribution after Chernobyl catastrophe

    International Nuclear Information System (INIS)

    It was investigated the evidence of gastroduodenal bleeding between Belarus population from 1989 to 1996 period. 27981 occurrences of this disease were registered. The annual permanent growth of the disease was revealed. Between persons, having worked in the Chernobyl region in the first year after the catastrophe, it was found the ulcer disease distribution in 7 times greater than between the whole population. It was concluded about heavy course of ulcer disease in residents of Belarus in the modern conditions

  6. Underwater studies in the regions of 'Komsomolets' nuclear submarine catastrophe

    International Nuclear Information System (INIS)

    There is a summary of the results of an expedition in the area of the 'Komsomolets' nuclear submarine catastrophe. The submarine sunk in the Norvegian Sea, 1690 m deep-seated in April 1989. The ecological situation was studied, radioactivity levels onboard the submarine and around it were measured. Visual inspections of the submarine and its parts have shown permissible levels of radioactive contamination. 1 ref., 3 figs

  7. Relativistic tidal disruption events

    Directory of Open Access Journals (Sweden)

    Levan A.

    2012-12-01

    Full Text Available In March 2011 Swift detected an extremely luminous and long-lived outburst from the nucleus of an otherwise quiescent, low luminosity (LMC-like galaxy. Named Swift J1644+57, its combination of high-energy luminosity (1048 ergs s−1 at peak, rapid X-ray variability (factors of >100 on timescales of 100 seconds and luminous, rising radio emission suggested that we were witnessing the birth of a moderately relativistic jet (Γ ∼ 2 − 5, created when a star is tidally disrupted by the supermassive black hole in the centre of the galaxy. A second event, Swift J2058+0516, detected two months later, with broadly similar properties lends further weight to this interpretation. Taken together this suggests that a fraction of tidal disruption events do indeed create relativistic outflows, demonstrates their detectability, and also implies that low mass galaxies can host massive black holes. Here, I briefly outline the observational properties of these relativistic tidal flares observed last year, and their evolution over the first year since their discovery.

  8. MD 751: Train Instability Threshold

    CERN Document Server

    Carver, Lee Robert; Metral, Elias; Salvant, Benoit; Levens, Tom; Nisbet, David; Zobov, M; CERN. Geneva. ATS Department

    2016-01-01

    The purpose of this MD is to measure the octupole current thresholds for stability for a single bunch, and then make an immediate comparison (with the same operational settings) for a train of 72 bunches separated by 25ns. From theory, the expected thresholds should be similar. Any discrepancy between the two cases will be of great interest as it could indicate the presence of additional mechanisms that contribute to the instability threshold, for example electron cloud.

  9. Lower Hearing Threshold by Noise

    Institute of Scientific and Technical Information of China (English)

    龙长才; 邵峰; 张燕萍; 秦佑国

    2004-01-01

    We demonstrate that noise can be a benefit factor that enables us to hear weaker signals. We measured the hearing thresholds of subjects for pure tone in different noise levels. The results show that pure tone thresholds with noise of some levels are lower than that without noise. The largest down-shift of the threshold by noise among the examined subjects is 5. 7dB, and the smallest is 1.7dB.

  10. Olfactory threshold in Parkinson's disease.

    OpenAIRE

    Quinn, N P; M.N. Rossor; Marsden, C. D.

    1987-01-01

    Olfactory threshold to differing concentrations of amyl acetate was determined in 78 subjects with idiopathic Parkinson's disease and 40 age-matched controls. Impaired olfactory threshold (previously reported by others) was confirmed in Parkinsonian subjects compared with controls. There was no significant correlation between olfactory threshold and age, sex, duration of disease, or current therapy with levodopa or anticholinergic drugs. In a sub-group of 14 levodopa-treated patients with sev...

  11. Disruptions in the TFTR tokamak

    International Nuclear Information System (INIS)

    For a successful reactor, it will be useful to predict the occurrence of disruptions and to understand disruption effects including how a plasma disrupts onto the wall and how reproducibly it does so. Studies of disruptions on TFTR at both high-βpol and high-density have shown that, in both types, a fast growing m/n=1/1 mode plays an important role. In highdensity disruptions, a newly observed fast m/n = 1/1 mode occurs early in the thermal decay phase. For the first time in TFTR q-profile measurements just prior to disruptions have been made. Experimental studies of heat deposition patterns on the first wall of TFTR due to disruptions have provided information on MHD phenomena prior to or during the disruption, how the energy is released to the wall, and the reproducibility of the heat loads from disruptions. This information is important in the design of future devices such as ITER. Several new processes of runaway electron generation are theoretically suggested and their application to TFTR and ITER is considered, together with a preliminary assessment of x-ray data from runaways generated during disruptions

  12. Safeguards as catastrophic risk management: insights and projections

    International Nuclear Information System (INIS)

    The system of international agreements designed to prevent the use of nuclear weapons and to control the spread of nuclear weapons, materials and technologies (collectively referred to as the nuclear arms control and nonproliferation regimes) is posited as humanity.s first attempt to mitigate a man-made global catastrophic risk. By extrapolating general principles of government response to risk from the arms control and nonproliferation regimes, a model of international regime building for catastrophic risk mitigation is constructed. This model provides the context for an examination of the system of safeguards implemented by the International Atomic Energy Agency (IAEA), which serves as the nuclear nonproliferation regime.s verification and enforcement mechanism and thereby constitutes the regime's most completely developed discrete mechanism for risk mitigation (a 'system within a system'). An assessment of the history, evolution and effectiveness of the IAEA safeguards system in the context of the regimes-as-risk-mitigation model reveals some general principles for risk-mitigation regimes which are then applied to the safeguards system to identify ways in which it may be strengthened. Finally, the IAEA safeguards system is posited as the prototype verification/enforcement mechanism for future risk mitigation regimes that governments will be compelled to create in the face of new global catastrophic risks that technological advance will inevitably create. (author)

  13. The impact of possible climate catastrophes on global warming policy

    International Nuclear Information System (INIS)

    Recent studies on global warming have introduced the inherent uncertainties associated with the costs and benefits of climate policies and have often shown that abatement policies are likely to be less aggressive or postponed in comparison to those resulting from traditional cost-benefit analyses (CBA). Yet, those studies have failed to include the possibility of sudden climate catastrophes. The aim of this paper is to account simultaneously for possible continuous and discrete damages resulting from global warming, and to analyse their implications on the optimal path of abatement policies. Our approach is related to the new literature on investment under uncertainty, and relies on some recent developments of the real option in which we incorporated negative jumps (climate catastrophes) in the stochastic process corresponding to the net benefits associated with the abatement policies. The impacts of continuous and discrete climatic risks can therefore be considered separately. Our numerical applications lead to two main conclusions: (i) gradual, continuous uncertainty in the global warming process is likely to delay the adoption of abatement policies as found in previous studies, with respect to the standard CBA; however (ii) the possibility of climate catastrophes accelerates the implementation of these policies as their net discounted benefits increase significantly

  14. Bifurcation and catastrophe of seepage flow system in broken rock

    Institute of Scientific and Technical Information of China (English)

    MIAO Xie-xing; LI Shun-cai; CHEN Zhan-qing

    2009-01-01

    The study of dynamical behavior of water or gas flows in broken rock is a basic research topic among a series of key projects about stability control of the surrounding rocks in mines and the prevention of some disasters such as water inrush or gas outburst and the protection of the groundwater resource. It is of great theoretical and engineering importance in respect of promo-tion of security in mine production and sustainable development of the coal industry. According to the non-Darcy property of seepage flow in broken rock dynamic equations of non-Darcy and non-steady flows in broken rock are established. By dimensionless transformation, the solution diagram of steady-states satisfying the given boundary conditions is obtained. By numerical analysis of low relaxation iteration, the dynamic responses corresponding to the different flow parameters have been obtained. The stability analysis of the steady-states indicate that a saddle-node bifurcaton exists in the seepage flow system of broken rock. Consequently, using catastrophe theory, the fold catastrophe model of seepage flow instability has been obtained. As a result, the bifurcation curves of the seepage flow systems with different control parameters are presented and the standard potential function is also given with respect to the generalized state variable for the fold catastrophe of a dynamic system of seepage flow in broken rock.

  15. Catastrophic rupture of lunar rocks - A Monte Carlo simulation

    Science.gov (United States)

    Hoerz, F.; Schneider, E.; Gault, D. E.; Hartung, J. B.; Brownlee, D. E.

    1975-01-01

    A computer model based on Monte Carlo techniques was developed to simulate the destruction of lunar rocks by 'catastrophic rupture' due to meteoroid impact. Energies necessary to accomplish catastrophic rupture were derived from laboratory experiments. A crater-production rate derived from lunar rocks was utilized to calculate absolute time scales. Calculated median survival times for crystalline lunar rocks are 1.9, 4.6, 10.3, and 22 m.y. for rock masses of 10, 100, 1000, and 10,000 g, respectively. Corresponding times of 6, 14.5, 32, and 68 million years are required before the probability of destruction reaches 0.99. These results are consistent with absolute exposure ages measured on returned rocks. Some results also substantiate previous conclusions that the catastrophic-rupture process is significantly more effective in obliterating lunar rocks than mass wasting by single-particle abrasion. The view is also corroborated that most rocks presently on the lunar surface either are exhumed from the regolith or are fragments of much larger boulders rather than primary ejecta excavated from pristine bedrock.

  16. Molecular and Mechanical Causes of Microtubule Catastrophe and Aging.

    Science.gov (United States)

    Zakharov, Pavel; Gudimchuk, Nikita; Voevodin, Vladimir; Tikhonravov, Alexander; Ataullakhanov, Fazoil I; Grishchuk, Ekaterina L

    2015-12-15

    Tubulin polymers, microtubules, can switch abruptly from the assembly to shortening. These infrequent transitions, termed "catastrophes", affect numerous cellular processes but the underlying mechanisms are elusive. We approached this complex stochastic system using advanced coarse-grained molecular dynamics modeling of tubulin-tubulin interactions. Unlike in previous simplified models of dynamic microtubules, the catastrophes in this model arise owing to fluctuations in the composition and conformation of a growing microtubule tip, most notably in the number of protofilament curls. In our model, dynamic evolution of the stochastic microtubule tip configurations over a long timescale, known as the system's "aging", gives rise to the nonexponential distribution of microtubule lifetimes, consistent with experiment. We show that aging takes place in the absence of visible changes in the microtubule wall or tip, as this complex molecular-mechanical system evolves slowly and asymptotically toward the steady-state level of the catastrophe-promoting configurations. This new, to our knowledge, theoretical basis will assist detailed mechanistic investigations of the mechanisms of action of different microtubule-binding proteins and drugs, thereby enabling accurate control over the microtubule dynamics to treat various pathologies. PMID:26682815

  17. Genomic catastrophes frequently arise in esophageal adenocarcinoma and drive tumorigenesis.

    Science.gov (United States)

    Nones, Katia; Waddell, Nicola; Wayte, Nicci; Patch, Ann-Marie; Bailey, Peter; Newell, Felicity; Holmes, Oliver; Fink, J Lynn; Quinn, Michael C J; Tang, Yue Hang; Lampe, Guy; Quek, Kelly; Loffler, Kelly A; Manning, Suzanne; Idrisoglu, Senel; Miller, David; Xu, Qinying; Waddell, Nick; Wilson, Peter J; Bruxner, Timothy J C; Christ, Angelika N; Harliwong, Ivon; Nourse, Craig; Nourbakhsh, Ehsan; Anderson, Matthew; Kazakoff, Stephen; Leonard, Conrad; Wood, Scott; Simpson, Peter T; Reid, Lynne E; Krause, Lutz; Hussey, Damian J; Watson, David I; Lord, Reginald V; Nancarrow, Derek; Phillips, Wayne A; Gotley, David; Smithers, B Mark; Whiteman, David C; Hayward, Nicholas K; Campbell, Peter J; Pearson, John V; Grimmond, Sean M; Barbour, Andrew P

    2014-01-01

    Oesophageal adenocarcinoma (EAC) incidence is rapidly increasing in Western countries. A better understanding of EAC underpins efforts to improve early detection and treatment outcomes. While large EAC exome sequencing efforts to date have found recurrent loss-of-function mutations, oncogenic driving events have been underrepresented. Here we use a combination of whole-genome sequencing (WGS) and single-nucleotide polymorphism-array profiling to show that genomic catastrophes are frequent in EAC, with almost a third (32%, n=40/123) undergoing chromothriptic events. WGS of 22 EAC cases show that catastrophes may lead to oncogene amplification through chromothripsis-derived double-minute chromosome formation (MYC and MDM2) or breakage-fusion-bridge (KRAS, MDM2 and RFC3). Telomere shortening is more prominent in EACs bearing localized complex rearrangements. Mutational signature analysis also confirms that extreme genomic instability in EAC can be driven by somatic BRCA2 mutations. These findings suggest that genomic catastrophes have a significant role in the malignant transformation of EAC. PMID:25351503

  18. Fast Quasi-Threshold Editing

    CERN Document Server

    Brandes, Ulrik; Strasser, Ben; Wagner, Dorothea

    2015-01-01

    We introduce Quasi-Threshold Mover (QTM), an algorithm to solve the quasi-threshold (also called trivially perfect) graph editing problem with edge insertion and deletion. Given a graph it computes a quasi-threshold graph which is close in terms of edit count. This edit problem is NP-hard. We present an extensive experimental study, in which we show that QTM is the first algorithm that is able to scale to large real-world graphs in practice. As a side result we further present a simple linear-time algorithm for the quasi-threshold recognition problem.

  19. Albania - Thresholds I and II

    Data.gov (United States)

    Millenium Challenge Corporation — From 2006 to 2011, the government of Albania (GOA) received two Millennium Challenge Corporation (MCC) Threshold Programs totaling $29.6 million. Albania received...

  20. Watershed safety and quality control by safety threshold method

    Science.gov (United States)

    Da-Wei Tsai, David; Mengjung Chou, Caroline; Ramaraj, Rameshprabu; Liu, Wen-Cheng; Honglay Chen, Paris

    2014-05-01

    Taiwan was warned as one of the most dangerous countries by IPCC and the World Bank. In such an exceptional and perilous island, we would like to launch the strategic research of land-use management on the catastrophe prevention and environmental protection. This study used the watershed management by "Safety Threshold Method" to restore and to prevent the disasters and pollution on island. For the deluge prevention, this study applied the restoration strategy to reduce total runoff which was equilibrium to 59.4% of the infiltration each year. For the sediment management, safety threshold management could reduce the sediment below the equilibrium of the natural sediment cycle. In the water quality issues, the best strategies exhibited the significant total load reductions of 10% in carbon (BOD5), 15% in nitrogen (nitrate) and 9% in phosphorus (TP). We found out the water quality could meet the BOD target by the 50% peak reduction with management. All the simulations demonstrated the safety threshold method was helpful to control the loadings within the safe range of disasters and environmental quality. Moreover, from the historical data of whole island, the past deforestation policy and the mistake economic projects were the prime culprits. Consequently, this study showed a practical method to manage both the disasters and pollution in a watershed scale by the land-use management.

  1. The 1985 Nevado del Ruiz volcano catastrophe: anatomy and retrospection

    Science.gov (United States)

    Voight, Barry

    1990-12-01

    This paper seeks to analyze in an objective way the circumstances and events that contributed to the 1985 Nevado del Ruiz catastrophe, in order to provide useful guidelines for future emergencies. The paper is organized into two principal parts. In the first part, an Anatomy of the catastrophe is developed as a step-by-step chronicle of events and actions taken by individuals and organizations during the period November 1984 through November 1985. This chronicle provides the essential background for the crucial events of November 13. This year-long period is broken down further to emphasize important chapters: the gradual awareness of the awakening of the volcano; a long period of institutional skepticism reflecting an absence of credibility; the closure of the credibility gap with the September 11 phreatic eruption, followed by an intensive effort to gird for the worst; and a detailed account of the day of reckoning. The second part of the paper, Retrospection, examines the numerous complicated factors that influenced the catastrophic outcome, and attempts to cull a few "lessons from Armero" in order to avoid similar occurrences in the future. In a nutshell, the government on the whole acted responsibly but was not willing to bear the economic or political costs of early evacuation or a false alarm. Science accurately foresaw the hazards but was insufficiently precise to render reliable warning of the crucial event at the last possible minute. Catastrophe was therefore a calculated risk, and this combination - the limitations of prediction/detection, the refusal to bear a false alarm and the lack of will to act on the uncertain information available - provided its immediate and most obvious causes. But because the crucial event occurred just two days before the Armero emergency management plan was to be critically examined and improved, the numerous circumstances which delayed progress of emergency management over the previous year also may be said to have

  2. Cell disruption for microalgae biorefineries.

    Science.gov (United States)

    Günerken, E; D'Hondt, E; Eppink, M H M; Garcia-Gonzalez, L; Elst, K; Wijffels, R H

    2015-01-01

    Microalgae are a potential source for various valuable chemicals for commercial applications ranging from nutraceuticals to fuels. Objective in a biorefinery is to utilize biomass ingredients efficiently similarly to petroleum refineries in which oil is fractionated in fuels and a variety of products with higher value. Downstream processes in microalgae biorefineries consist of different steps whereof cell disruption is the most crucial part. To maintain the functionality of algae biochemicals during cell disruption while obtaining high disruption yields is an important challenge. Despite this need, studies on mild disruption of microalgae cells are limited. This review article focuses on the evaluation of conventional and emerging cell disruption technologies, and a comparison thereof with respect to their potential for the future microalgae biorefineries. The discussed techniques are bead milling, high pressure homogenization, high speed homogenization, ultrasonication, microwave treatment, pulsed electric field treatment, non-mechanical cell disruption and some emerging technologies. PMID:25656098

  3. Evaluation of indirect loss from hypothetical catastrophes in two regions with different economic development levels in China

    Directory of Open Access Journals (Sweden)

    W. Xie

    2012-11-01

    Full Text Available This study evaluates and compares the indirect economic loss (IEL resulting from two hypothetical catastrophes occurring in China – in developed Shanghai and in less-developed Sichuan – to provide new measures of disaster reduction. IEL was divided into indirect economic loss due to the disruption of production process (IEL I and indirect economic loss induced by the disturbance of industrial lines (IEL II. An input-output model was used to assess these two types of IEL. The study showed that (1 developed regions may be more vulnerable with respect to IEL; (2 IEL II is the primary factor contributing to total IEL; (3 decision makers need to focus on IEL II beside IEL I which is usually the main disaster-reduction target after a disaster; and (4 tradeoff between economic growth and disaster prevention is needed to achieve regional sustainable development.

  4. Evaluation of indirect loss from hypothetical catastrophes in two regions with different economic development levels in China

    Science.gov (United States)

    Xie, W.; Li, N.; Wu, J.-D.; Liu, X.-Q.

    2012-11-01

    This study evaluates and compares the indirect economic loss (IEL) resulting from two hypothetical catastrophes occurring in China - in developed Shanghai and in less-developed Sichuan - to provide new measures of disaster reduction. IEL was divided into indirect economic loss due to the disruption of production process (IEL I) and indirect economic loss induced by the disturbance of industrial lines (IEL II). An input-output model was used to assess these two types of IEL. The study showed that (1) developed regions may be more vulnerable with respect to IEL; (2) IEL II is the primary factor contributing to total IEL; (3) decision makers need to focus on IEL II beside IEL I which is usually the main disaster-reduction target after a disaster; and (4) tradeoff between economic growth and disaster prevention is needed to achieve regional sustainable development.

  5. Disruptive camouflage impairs object recognition

    OpenAIRE

    Richard J. Webster; Hassall, Christopher; Herdman, Chris M.; Godin, Jean-Guy J.; Sherratt, Thomas N.

    2013-01-01

    Whether hiding from predators, or avoiding battlefield casualties, camouflage is widely employed to prevent detection. Disruptive coloration is a seemingly well-known camouflage mechanism proposed to function by breaking up an object's salient features (for example their characteristic outline), rendering objects more difficult to recognize. However, while a wide range of animals are thought to evade detection using disruptive patterns, there is no direct experimental evidence that disruptive...

  6. Life below the threshold.

    Science.gov (United States)

    Castro, C

    1991-01-01

    This article explains that malnutrition, poor health, and limited educational opportunities plague Philippine children -- especially female children -- from families living below the poverty threshold. Nearly 70% of households in the Philippines do not meet the required daily level of nutritional intake. Because it is often -- and incorrectly -- assumed that women's nutritional requirements are lower than men's, women suffer higher rates of malnutrition and poor health. A 1987 study revealed that 11.7% of all elementary students were underweight and 13.9% had stunted growths. Among elementary-school girls, 17% were malnourished and 40% suffered from anemia (among lactating mothers, more than 1/2 are anemic). A 1988 Program for Decentralized Educational Development study showed that grade VI students learn only about 1/2 of what they are supposed to learn. 30% of the children enrolled in grade school drop out before they reach their senior year. The Department of Education, Culture and Sports estimates that some 2.56 million students dropped out of school in l989. That same year, some 3.7 million children were counted as part of the labor force. In Manila alone, some 60,000 children work the streets, whether doing odd jobs or begging, or turning to crime or prostitution. the article tells the story of a 12 year-old girl named Ging, a 4th grader at a public school and the oldest child in a poor family of 6 children. The undernourished Ging dreams of a good future for her family and sees education as a way out of poverty; unfortunately, her time after school is spend working in the streets or looking after her family. She considers herself luckier than many of the other children working in the streets, since she at least has a family. PMID:12285009

  7. Endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Mandrup, Karen

    BACKGROUND: Endocrine disrupting chemicals (EDCs) may contribute to reproductive changes in boys in the Western world, however, less is known about influence of EDCs in women. The incidence of precocious breast development is increasing in USA and Europe and mammary gland development has been...... examination showed changes in epithelial morphology in male (hypertrophic epithelium) and female (lobuloalveolar morphology) mammary glands in adult rats exposed to phytoestrogens. Anti-androgenic chemicals showed signs of feminisation of adult male mammary glands. No effects of anti-androgens were observed...... in female mammary glands. The histological changes observed in adult female and male mammary glands were not present consistently in the groups of estrogenic or anti-androgenic chemicals and may be due to other modes of action of thechemicals. Female genital malformations were affected by the potent...

  8. Second threshold in weak interactions

    NARCIS (Netherlands)

    Veltman, M.J.G.

    1977-01-01

    The point of view that weak interactions must have a second threshold below 300 – 600 GeV is developed. Above this threshold new physics must come in. This new physics may be the Higgs system, or some other nonperturbative system possibly having some similarities to the Higgs system. The limit of la

  9. Threshold Concepts and Information Literacy

    Science.gov (United States)

    Townsend, Lori; Brunetti, Korey; Hofer, Amy R.

    2011-01-01

    What do we teach when we teach information literacy in higher education? This paper describes a pedagogical approach to information literacy that helps instructors focus content around transformative learning thresholds. The threshold concept framework holds promise for librarians because it grounds the instructor in the big ideas and underlying…

  10. Double scaling limits and airy functions for O(N) vector sigma models with elementary catastrophes or the catastrophe X9

    International Nuclear Information System (INIS)

    One and two vector sigma models are defined that possess catastrophes in their action. Each catastrophe defines a double scaling limit at N→∞. Critical indices are calculated and the Airy functions are shown to satisfy RG equations. Copyright copyright 1996 Academic Press, Inc

  11. Chernobyl catastrophe: Information for people living in the contaminated areas

    International Nuclear Information System (INIS)

    The radioactive blow-outs after the Chernobyl Nuclear Power Plant catastrophe reached many states. The largest amount of them (according to experts' estimations - 70%) fell out on the Belarus territory. The estimation of radioecological, medico-biological, economic and social consequences of the Chernobyl catastrophe has shown that unimaginable damage was incurred on Belarus and its territory became the zone of ecological calamity. More than 14 years have passed since the Chernobyl NPP accident but some of the problems caused by the catastrophe have not been solved. This is bound up, first of all, with a high collective dosage absorbed by the population, with difficulties in forecasting and prophylactics of remote radiological effects, with ecological and economic crisis. The consequences of the disaster greatly affect all the aspects of vital activities of the affected regions and the state as a whole. Destructive tendencies have been revealed in all spheres of the life activity of people who experienced radiation effects. The processes of social adaptation and socio-psychological support of the population inhabiting the contaminated territory and resettled as well, require considerable optimisation. Negative factors of the Chernobyl catastrophe, which are significant for human health can be divided into two groups as follows: radiation-based, directly related to influence of ionising radiation and non radiation based, related to changes in habitat and prolonged psychological stress. The specific peculiarities of psychogenic disorders caused by the catastrophe are determined by the following reasons: insufficient knowledge of radiation effects; constant apprehension for the health and well-being of themselves and their families, especially children; unexpected change of the life stereotype (forced resettlement, the break of the former life, changing the place and the character of work, etc.); the necessity of constant keeping precaution measures and prophylactic

  12. Catastrophic nanosecond laser induced damage in the bulk of potassium titanyl phosphate crystals

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Frank R., E-mail: frank.wagner@fresnel.fr; Natoli, Jean-Yves; Akhouayri, Hassan; Commandré, Mireille [Institut Fresnel, CNRS, Aix-Marseille Université, Ecole Centrale Marseille, Campus de St Jérôme, 13013 Marseille (France); Duchateau, Guillaume [CELIA, UMR 5107 Université Bordeaux 1-CNRS-CEA, 351 Cours de la Libération, 33405 Talence Cedex (France)

    2014-06-28

    Due to its high effective nonlinearity and the possibility to produce periodically poled crystals, potassium titanyl phosphate (KTiOPO{sub 4}, KTP) is still one of the economically important nonlinear optical materials. In this overview article, we present a large study on catastrophic nanosecond laser induced damage in this material and the very similar RbTiOPO{sub 4} (RTP). Several different systematic studies are included: multiple pulse laser damage, multi-wavelength laser damage in KTP, damage resistance anisotropy, and variations of the laser damage thresholds for RTP crystals of different qualities. All measurements were carried out in comparable experimental conditions using a 1064 nm Q-switched laser and some were repeated at 532 nm. After summarizing the experimental results, we detail the proposed model for laser damage in this material and discuss the experimental results in this context. According to the model, nanosecond laser damage is caused by light-induced generation of transient laser-damage precursors which subsequently provide free electrons that are heated by the same nanosecond pulse. We also present a stimulated Raman scattering measurement and confront slightly different models to the experimental data. Finally, the physical nature of the transient damage precursors is discussed and similarities and differences to laser damage in other crystals are pointed out.

  13. Repartnering after First Union Disruption

    Science.gov (United States)

    Wu, Zheng; Schimmele, Christoph M.

    2005-01-01

    Using data from the 1995 General Social Survey (N= 2,639), this study examines two competing repartnering choices made by Canadians after first union disruption: marriage or cohabitation. About 42% of women and 54% of men form a second union 5 years after union disruption, with cohabitation being the most prevalent choice. The timing of second…

  14. Stochastic catastrophe theory and instabilities in plasma turbulence

    International Nuclear Information System (INIS)

    Full text: A Langevin equation (LE) describing evolution of turbulence amplitude in plasma is analyzed from the aspect of stochastic catastrophe theory (SCT) so that turbulent plasma is considered as a stochastic gradient system. According to SCT the dynamics of the system is completely determined by the stochastic potential function and the maximum likelihood estimates of stable and unstable equilibria are associated with the modes and anti-modes, respectively, of the system's stationary probability density function. First order phase transitions occur at degenerate equilibrium points and the potential function at these points may be represented in a generic way. Since the diffusion function of plasma LE is not constant the probability density function (pdf) is not a reliable estimator of the number of stable states. We show that the generalized pdf represented as the product of the stationary pdf and the diffusion function is a reliable estimator of the stable states and that it can be evaluated from the zero mean crossing analysis of plasma turbulence signal. Stochastic bifurcations, and particularly the sudden (catastrophic) ones, are recognized from the pdf's obtained by the zero crossing analysis and we illustrate the applications of SCT in plasma turbulence on data obtained from the MAST (Mega Ampere Spherical Tokamak) for low (L), high (H) and unstable dithering (L/H) confinement regimes. The relationship of the transformation invariant zero-crossing function and SCT is shown to provide important information about the nature of edge localized modes (ELMs) and L-H transition. Finally we show that ELMs occur as a result of catastrophic (hard) bifurcations ruling out the self-organized criticality scenario for their origin. (author)

  15. Catastrophic events leading to de facto limits on liability

    International Nuclear Information System (INIS)

    This study conducts an overview of large technological systems in society to ascertain prevalence, if any, of situations that can lead to catastrophic effects where the resultant liabilities far exceed the insurances or assets subject to suit in court, thereby imposing de facto limits on liability. Several potential situations are examined: dam rupture, aircraft crash into a sports stadium, chemical plant accident, shipping disaster, and a toxic drug disaster. All of these events are estimated to have probabilities per year similar to or larger than a major nuclear accident and they are found to involve potential liability far exceeding the available resources, such as insurance, corporation assets, or government revenues

  16. Blue sky catastrophe as applied to modeling of cardiac rhythms

    Science.gov (United States)

    Glyzin, S. D.; Kolesov, A. Yu.; Rozov, N. Kh.

    2015-07-01

    A new mathematical model for the electrical activity of the heart is proposed. The model represents a special singularly perturbed three-dimensional system of ordinary differential equations with one fast and two slow variables. A characteristic feature of the system is that its solution performs nonclassical relaxation oscillations and simultaneously undergoes a blue sky catastrophe bifurcation. Both these factors make it possible to achieve a phenomenological proximity between the time dependence of the fast component in the model and an ECG of the human heart.

  17. Catastrophic medical protection: a plan for sharing excessive costs.

    Science.gov (United States)

    Hester, R D

    1982-01-01

    Cost sharing provisions in both private and public health insurance plans have greatly increased consumer out-of-pocket expenses for medical services in recent years. The effects of these provisions, coupled with the effects of massive unemployment, have been that many individuals are unable to afford adequate health insurance protection. To protect the nation's health, new proposals to expand health coverage have given rise to catastrophic health insurance. This new health policy priority may assist many low-wage and unemployed workers to meet their cost-sharing obligations in the face of rising medical costs. PMID:10298874

  18. Catastrophes and nuclear accidents in the former USSR

    International Nuclear Information System (INIS)

    In the former USSR, the nuclear safety, the environment protection and the preservation of workers and population health were not the first priority for the Soviet Union authorities. The fabrication of nuclear weapons, the construction of nuclear submarines and the production of an abundant energy source were the only goals at that time. This book describes and explains the circumstances of the nuclear catastrophes and accidents that have occurred during this era. It tries to estimate their impacts on populations and environment and their possible consequences in a near or far future. (J.S.)

  19. A general theory for flooding implementing cuspoids catastrophe

    International Nuclear Information System (INIS)

    This paper combines Kelvin-Helmholtz Theory and Catastrophe Theory to develop a general mathematical framework for the flooding phenomenon. The theoretical model proposed in this paper is based on the functional relationship between the gas and liquid flow rates expressed in terms of a modified Kutateladze number that takes into account the effects of entrainment and geometry. A large number of experimental data has been examined against the theoretical model prediction. In most cases, good agreement is obtained by empirically varying only one coefficient. (orig.)

  20. Music effect on pain threshold evaluated with current perception threshold

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: Music relieves anxiety and psychotic tension. This effect of music is applied to surgical operation in the hospital and dental office. It is still unclear whether this music effect is only limited to the psychological aspect but not to the physical aspect or whether its music effect is influenced by the mood or emotion of audience. To elucidate these issues, we evaluated the music effect on pain threshold by current perception threshold (CPT) and profile of mood states (POMC) test. METHODS: Healthy 30 subjects (12 men, 18 women, 25-49 years old, mean age 34.9) were tested. (1)After POMC test, all subjects were evaluated pain threshold with CPT by Neurometer (Radionics, USA) under 6 conditions, silence, listening to the slow tempo classic music, nursery music, hard rock music, classic paino music and relaxation music with 30 seconds interval. (2)After Stroop color word test as the stresser, pain threshold was evaluated with CPT under 2 conditions, silence and listening to the slow tempo classic music. RESULTS: Under litening to the music, CPT sores increased, especially 2 000 Hz level related with compression, warm and pain sensation. Type of music, preference of music and stress also affected CPT score. CONCLUSION: The present study demonstrated that the concentration on the music raise the pain threshold and that stress and mood influence the music effect on pain threshold.

  1. Incomplete spontaneous ureteral disruption

    International Nuclear Information System (INIS)

    Background. The aim of the authors was to present the case of spontaneous partial ureteral rupture during a renal colic, caused by an anorganic concrement in the proximal part of the left ureter, at the level of the transverse processus of L3. Case report. On the excretory urography imaging, the dilatation of the canal system, cups, necks and pyelon, was observed. At the level of the pyeloureteric passage, the contrast medium was leaking. The leakage was found to be extending along the psoas muscle to the pelvis. On the transversal CT imaging scans, the contrast medium was seen along the medial and dorsal part of the perirenal space, and in the distal part, along the psoas muscle to the pelvis. The ureter was imaged from the pyeloureterical rupture to the site of the concrement. No signs of the damage of the renal parenchyma or perirenal bleeding were detected. During surgery, the site of the rupture was found and also a lot of the perirenal and periureteral liquid. After the extraction of the concrement, the suture of the rupture was made. Postoperative urography and CT showed a normal ureteral image. Conclusions. At the spontaneous partial disruption of the ureter, the contrast medium is still seen in the ureter, distally from the site of the rupture and as extravasation along the psoas muscle. (author)

  2. Disrupting Ethnography through Rhizoanalysis

    Directory of Open Access Journals (Sweden)

    Diana Masny

    2014-10-01

    Full Text Available This article interrogates principles of ethnography in education proposed by Mills and Morton: raw tellings, analytic pattern, vignette and empathy. This article adopts a position that is uncomfortable, unconventional and interesting. It involves a deterritorialization/ rupture of ethnography in education in order to reterritorialize a different concept: rhizoanalysis, a way to position theory and data that is multilayered, complex and messy. Rhizoanalysis, the main focus of this article is not a method. It is an approach to research conditioned by a reality in which Deleuze and Guattari disrupt representation, interpretation and subjectivity. In this article, Multiple Literacies Theory, a theoretical and practical framework, becomes a lens to examine a rhizomatic study of a Korean family recently arrived to Australia and attending English as a second language classes. Observations and interviews recorded the daily lives of the family. The vignettes were selected by reading data intensively and immanently through a process of palpation, an innovative approach to educational research. Rhizoanalysis proposes to abandon the given and invent different ways of thinking about and doing research and what might happen when reading data differently, intensively and immanently, through Multiple Literacies Theory. Rhizoanalysis, a game-changer in the way research can be conducted, affords a different lens to tackle issues in education through research.

  3. Parton distributions with threshold resummation

    CERN Document Server

    Bonvini, Marco; Rojo, Juan; Rottoli, Luca; Ubiali, Maria; Ball, Richard D; Bertone, Valerio; Carrazza, Stefano; Hartland, Nathan P

    2015-01-01

    We construct a set of parton distribution functions (PDFs) in which fixed-order NLO and NNLO calculations are supplemented with soft-gluon (threshold) resummation up to NLL and NNLL accuracy respectively, suitable for use in conjunction with any QCD calculation in which threshold resummation is included at the level of partonic cross sections. These resummed PDF sets, based on the NNPDF3.0 analysis, are extracted from deep-inelastic scattering, Drell-Yan, and top quark pair production data, for which resummed calculations can be consistently used. We find that, close to threshold, the inclusion of resummed PDFs can partially compensate the enhancement in resummed matrix elements, leading to resummed hadronic cross-sections closer to the fixed-order calculation. On the other hand, far from threshold, resummed PDFs reduce to their fixed-order counterparts. Our results demonstrate the need for a consistent use of resummed PDFs in resummed calculations.

  4. Pain catastrophizing, physiological indexes, and chronic pain severity: tests of mediation and moderation models

    OpenAIRE

    Wolff, Brandy; Burns, John W.; Quartana, Phillip J.; Lofland, Kenneth; Bruehl, Stephen; Chung, Ok Y.

    2008-01-01

    Catastrophizing about pain is related to elevated pain severity and poor adjustment among chronic pain patients, but few physiological mechanisms by which pain catastrophizing maintains and exacerbates pain have been explored. We hypothesized that resting levels of lower paraspinal muscle tension and/or lower paraspinal and cardiovascular reactivity to emotional arousal may: (a) mediate links between pain catastrophizing and chronic pain intensity; (b) moderate these links such that only pati...

  5. Catastrophizing, Functional Disability and Pain Reports in Adults with Chronic Low Back Pain

    OpenAIRE

    1999-01-01

    OBJECTIVE: To test the hypothesis that subjective reports of pain severity, pain intensity and functional disability correlate positively with catastrophizing.PATIENTS: Adults with chronic low back pain for six months or longer presenting to a tertiary care Pain Management Unit.METHODS: Catastrophizing was measured with the Pain Catastrophizing Scale (PCS) in 40 subjects (23 males, 17 females). Functional disability was measured with the Pain Disability Index and pain severity/intensity was q...

  6. A gradient catastrophe mechanism in contexts of the phase change condition

    OpenAIRE

    Durmagambetov, A. A.

    2016-01-01

    The paper describes the mechanism of occurrence of a gradient catastrophe when changing phase. Materials shows that classical methods of estimation theory of functions do not fit the problem of studying the gradient catastrophe. We present material showing that the embedding theorem can not give an opportunity to study the process of a gradient catastrophe. In fact, work justifies pessimism Terence Tao in the insolvency of modern mathematics to solve the problem of the Navier-Stokes equations...

  7. Catastrophic failure in complex socio-technical systems

    Energy Technology Data Exchange (ETDEWEB)

    Weir, D. [Intercultural Management, Rue Dostoievski, BP 085, 06902 Sophia Antipolis (France)]. E-mail: dweir@tinyworld.co.uk

    2004-07-01

    This paper reviews the sequences leading to catastrophic failures in complex socio-technical systems. It traces some of the elements of an analytic framework to that proposed by Beer in Decision and Control, first published in 1966, and argues that these ideas are centrally relevant to a topic on which research interest has developed subsequently, the study of crises, catastrophes and disasters in complex socio-technical systems in high technology sectors. But while the system perspective is central, it is not by itself entirely adequate. The problems discussed cannot be discussed simply in terms of system parameters like variety, redundancy and complexity. Much empirical research supports the view that these systems typically operate in degraded mode. The degradations may be primarily initiated within the social components of the socio-technical system. Such variables as hierarchical position, actors' motivations and intentions are relevant to explain the ways in which communication systems typically operate to filter out messages from lower participants and to ignore the 'soft signals' issuing from small-scale and intermittent malfunctions. (author)

  8. Zeeman catastrophe machines as a toolkit for teaching chaos

    International Nuclear Information System (INIS)

    The investigation of chaotic motions and cooperative systems offers a magnificent opportunity to involve modern physics in the basic course of mechanics taught to engineering students. In this paper, it will be demonstrated that the Zeeman machine can be a versatile and motivating tool for students to acquire introductory knowledge about chaotic motion via interactive simulations. The Zeeman catastrophe machine is a typical example of a quasi-static system with hysteresis. It works in a relatively simple way and its properties can be understood very easily. Since the machine can be built easily and the simulation of its movement is also simple, the experimental investigation and the theoretical description can be connected intuitively. Although the Zeeman machine is known mainly for its quasi-static and catastrophic behaviour, its dynamic properties are also of interest with its typical chaotic features. By means of a periodically driven Zeeman machine, a wide range of chaotic properties of the simple systems can be demonstrated, such as bifurcation diagrams, chaotic attractors, transient chaos, Lyapunov exponents and so on. This paper is organically linked to our website (http://csodafizika.hu/zeeman) where the discussed simulation programs can be downloaded. In a second paper, the novel construction of a network of Zeeman machines will be presented to study the properties of cooperative systems. (paper)

  9. Iodine and thyroid gland with or without nuclear catastrophe

    Directory of Open Access Journals (Sweden)

    Kovačev-Zavišić Branka

    2012-01-01

    Full Text Available Introduction. Iodine, as a trace element, is a necessary and limiting substrate for thyroid gland hormone synthesis. It is an essential element that enables the thyroid gland to produce thyroid hormones thyroxine (T4 and triiodothyronine (T3. Synthesis of Thyroid Hormones and Iodine Metabolism. Three iodine molecules are added to make triiodothyronine, and four for thyroxine - the two key hormones produced by the thyroid gland. Iodine deficiency. The proper daily amount of iodine is required for optimal thyroid function. Iodine deficiency can cause hypothyroidism, developmental brain disorders and goiter. Iodine deficiency is the single most common cause of preventable mental retardation and brain damage in the world. It also decreases child survival, causes goiters, and impairs growth and development. Iodine deficiency disorders in pregnant women cause miscarriages, stillbirths, and other complications. Children with iodine deficiency disorders can grow up stunted, apathetic, mentally retarded, and incapable of normal movements, speech or hearing. Excessive Iodine Intake. Excessive iodine intake, which can trigger autoimmune thyroid disease and dysfunction, is on the other side. Iodine use in Case of Nuclear Catastrophe. In addition to other severe consequences of radioactivity, high amount of radioactive iodine causes significant increase in incidence of thyroid gland carcinoma after some of the nuclear catastrophes (Hiroshima, Nagasaki, Chernobyl, Fukushima. The incidence of thyroid carcinoma was increased mostly in children. This paper was aimed at clarifying some of the possibilities of prevention according to the recommendations given by the World Health Organization.

  10. Catastrophic failure in complex socio-technical systems

    International Nuclear Information System (INIS)

    This paper reviews the sequences leading to catastrophic failures in complex socio-technical systems. It traces some of the elements of an analytic framework to that proposed by Beer in Decision and Control, first published in 1966, and argues that these ideas are centrally relevant to a topic on which research interest has developed subsequently, the study of crises, catastrophes and disasters in complex socio-technical systems in high technology sectors. But while the system perspective is central, it is not by itself entirely adequate. The problems discussed cannot be discussed simply in terms of system parameters like variety, redundancy and complexity. Much empirical research supports the view that these systems typically operate in degraded mode. The degradations may be primarily initiated within the social components of the socio-technical system. Such variables as hierarchical position, actors' motivations and intentions are relevant to explain the ways in which communication systems typically operate to filter out messages from lower participants and to ignore the 'soft signals' issuing from small-scale and intermittent malfunctions. (author)

  11. Crisis Management Aspects of Bam Catastrophic Earthquake: Review Article

    Directory of Open Access Journals (Sweden)

    Homayoun Sadeghi-Bazargani

    2015-03-01

    Full Text Available Background: Bam earthquake was the most catastrophic natural disasters in recent years. The aim of this study was to review different aspects of crisis manage­ment during and after the catastrophic earthquake in Bam City, Iran.Methods: Data needed for this systematic review were collected through search­ing PubMed, EMBASE and SID databases, for the period from 2003 to 2011. Keywords included earthquake, Iran and Bam earthquake. The data were summarized and were analyzed using Content Analysis.Results: Out of 422 articles, 25 articles were included in the study. Crisis Manage­ment aspects and existing pitfalls were classified into seven categories including planning and organization, human resource management, management of logistics, international humanitarian aids, field performance of the military and security forces, health and medical service provision, and information manage­ment. Positive aspects and major pitfalls of crisis management have been introduced in all the mentioned categories. Conclusion: The available evidence indicated poor crisis management during Bam earthquake that resulted in aggravating the losses as well as diminishing the effect of interventions. Thus, concerning the importance of different aspects of the crisis management and the high prevalence of disasters in Iran, the observed vulnerability in disaster management process should be addressed.

  12. Tatra's forests will recover from catastrophe for decades

    International Nuclear Information System (INIS)

    Windy tornado in Tatra's national park (TANAP, High Tatras, Slovakia) at the end of 2004 caused extensive ecological catastrophe and economic losses. Wind has totally damaged the trees in more than one fourth of forest area, which is administrated by state forests of TANAP. Next fourth of forest area has impaired structure. Mostly coniferous forests have fallen down not only in High Tatras, but also in Horehronie, Kysuce, Orava and Spis. According to estimates around 2.5 million cubic meters of wood have lain on the ground in High Tatras. This wood must be precipitately processed. In another regions totally from 800 to 900 thousands cubic meters are overcame by wind. Ecological catastrophe has come in High Tatras. Totally damaged large forests areas need to be recovered for long decades. 90 per cent of annual Slovakian wood cutting represents totally 2.5 million cubic meters. The state will invest in forest recovery from sale of calamity stuff. Reforestation of one hectare of forest costs from 80 to 90 thousands Slovak crowns (∼2666-3000 USD). Another remedies at the age to five years represent from 40 to 50 thousands Slovak crowns (1333-16666 USD). Around 1.6 billion Slovak crown (∼53.333 million USD) will be needed for reforestation of 12 thousands hectares of TANAP

  13. Observing a catastrophic thermokarst lake drainage in northern Alaska

    Science.gov (United States)

    Jones, Benjamin M.; Arp, Christopher D.

    2015-01-01

    The formation and drainage of thermokarst lakes have reshaped ice-rich permafrost lowlands in the Arctic throughout the Holocene. North of Teshekpuk Lake, on the Arctic Coastal Plain of northern Alaska, thermokarst lakes presently occupy 22.5% of the landscape, and drained thermokarst lake basins occupy 61.8%. Analysis of remotely sensed imagery indicates that nine lakes (>10 ha) have drained in the 1,750 km2 study area between 1955 and 2014. The most recent lake drainage was observed using in situ data loggers providing information on the duration and magnitude of the event, and a nearby weather station provided information on the environmental conditions preceding the lake drainage. Lake 195 (L195), an 80 ha thermokarst lake with an estimated water volume of ~872,000 m3, catastrophically drained on 05 July 2014. Abundant winter snowfall and heavy early summer precipitation resulted in elevated lake water levels that likely promoted bank overtopping, thermo-erosion along an ice-wedge network, and formation of a 9 m wide, 2 m deep, and 70 m long drainage gully. The lake emptied in 36 hours, with 75% of the water volume loss occurring in the first ten hours. The observed peak discharge of the resultant flood was 25 m3/s, which is similar to that in northern Alaska river basins whose areas are more than two orders of magnitude larger. Our findings support the catastrophic nature of sudden lake drainage events and the mechanistic hypotheses developed by J. Ross Mackay.

  14. Threshold models in radiation carcinogenesis

    International Nuclear Information System (INIS)

    Cancer incidence and mortality data from the atomic bomb survivors cohort has been analyzed to allow for the possibility of a threshold dose response. The same dose-response models as used in the original papers were fit to the data. The estimated cancer incidence from the fitted models over-predicted the observed cancer incidence in the lowest exposure group. This is consistent with a threshold or nonlinear dose-response at low-doses. Thresholds were added to the dose-response models and the range of possible thresholds is shown for both solid tumor cancers as well as the different leukemia types. This analysis suggests that the A-bomb cancer incidence data agree more with a threshold or nonlinear dose-response model than a purely linear model although the linear model is statistically equivalent. This observation is not found with the mortality data. For both the incidence data and the mortality data the addition of a threshold term significantly improves the fit to the linear or linear-quadratic dose response for both total leukemias and also for the leukemia subtypes of ALL, AML, and CML

  15. When Disruptive Approaches Meet Disruptive Technologies: Learning at a Distance.

    Science.gov (United States)

    Gibson, Chere Campbell

    2000-01-01

    Reviews research on constructivism in learning and selection of learning strategies. Suggests linking constructivism with instructional technologies for continuing medical education in order to "disrupt" reactive, habitual ways of learning and encourage active engagement. (SK)

  16. Agricultural Mechanism of Spreading Catastrophe Risk in China and Legislation Conception

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This paper introduces agricultural catastrophe and its characteristics,and conducts comparative analysis on existing mechanism of spreading agricultural catastrophe risk,indicating that the mechanism of administrative remedy has the greatest efficiency and highest cost;the mechanism of social assistance has the lowest cost,but its efficiency is lowest and there are unstable factors;market mechanism,namely the insurance of agricultural catastrophe,is the rational choice of agricultural department in mechanism of risk spreading.This paper analyzes the status quo of China’s insurance of agricultural catastrophe,indicating that the main body of management in China’s insurance of agricultural catastrophe is missing.In addition,the market demand is critically scanty,and insurance of agricultural catastrophe lacks external development environment.The gap of China’s insurance law of agricultural catastrophe has become the greatest obstacle to the development of insurance of agricultural catastrophe.From legislative purpose,basic principle,nature,main body of legal relations,management range,policy support,supervision and management and so on,the legislation conception of China’s insurance of agricultural catastrophe is put forward.

  17. Endocrine Effects of Circadian Disruption.

    Science.gov (United States)

    Bedrosian, Tracy A; Fonken, Laura K; Nelson, Randy J

    2016-01-01

    Disruption of circadian rhythms, provoked by artificial lighting at night, inconsistent sleep-wake schedules, and transmeridian air travel, is increasingly prevalent in modern society. Desynchrony of biological rhythms from environmental light cycles has dramatic consequences for human health. In particular, disrupting homeostatic oscillations in endocrine tissues and the hormones that these tissues regulate can have cascading effects on physiology and behavior. Accumulating evidence suggests that chronic disruption of circadian organization of endocrine function may lead to metabolic, reproductive, sleep, and mood disorders. This review discusses circadian control of endocrine systems and the consequences of distorting rhythmicity of these systems. PMID:26208951

  18. Guidelines for Auditory Threshold Measurement for Significant Threshold Shift.

    Science.gov (United States)

    Campbell, Kathleen; Hammill, Tanisha; Hoffer, Michael; Kil, Jonathan; Le Prell, Colleen

    2016-09-01

    The purpose of this article is to provide guidelines for determining a Significant Noise-Induced Threshold Shift in clinical trials involving human populations. The article reviews recommendations for the standards to be referenced for human subjects, equipment, test environment, and personnel. Additional guidelines for military populations are provided. Guidelines for the calibration of audiometers, sound booth noise levels, and immitance equipment are provided. In addition the guidance provides specific suggestions for the subjects history before study onset, and otoscopy.Test frequencies for threshold determination and methods of threshold determination are reviewed for both air conduction and bone conduction for both baseline testing and later determination of either a temporary (TTS) or permanent threshold shift (PTS). Once a Significant Noise-Induced Threshold Shift has been determined, subjects should be retested, conductive component should be ruled out or addressed, and the subject should be counseled or referred for additional medical evaluation. Guidance for reporting procedures and the computerized study database are described. Finally, experimental designs suggested for noise-induced otoprotection clinical trials are described. PMID:27518134

  19. Prediction of density limit disruptions on the J-TEXT tokamak

    Science.gov (United States)

    Wang, S. Y.; Chen, Z. Y.; Huang, D. W.; Tong, R. H.; Yan, W.; Wei, Y. N.; Ma, T. K.; Zhang, M.; Zhuang, G.

    2016-05-01

    Disruption mitigation is essential for the next generation of tokamaks. The prediction of plasma disruption is the key to disruption mitigation. A neural network combining eight input signals has been developed to predict the density limit disruptions on the J-TEXT tokamak. An optimized training method has been proposed which has improved the prediction performance. The network obtained has been tested on 64 disruption shots and 205 non-disruption shots. A successful alarm rate of 82.8% with a false alarm rate of 12.3% can be achieved at 4.8 ms prior to the current spike of the disruption. It indicates that more physical parameters than the current physical scaling should be considered for predicting the density limit. It was also found that the critical density for disruption can be predicted several tens of milliseconds in advance in most cases. Furthermore, if the network is used for real-time density feedback control, more than 95% of the density limit disruptions can be avoided by setting a proper threshold.

  20. Vortex disruption by magnetohydrodynamic feedback

    CERN Document Server

    Mak, Julian; Hughes, D W

    2016-01-01

    In an electrically conducting fluid, vortices stretch out a weak, large-scale magnetic field to form strong current sheets on their edges. Associated with these current sheets are magnetic stresses, which are subsequently released through reconnection, leading to vortex disruption, and possibly even destruction. This disruption phenomenon is investigated here in the context of two-dimensional, homogeneous, incompressible magnetohydrodynamics. We derive a simple order of magnitude estimate for the magnetic stresses --- and thus the degree of disruption --- that depends on the strength of the background magnetic field (measured by the parameter $M$, a ratio between the Alfv\\'en speed and a typical flow speed) and on the magnetic diffusivity (measured by the magnetic Reynolds number $\\mbox{Rm}$). The resulting estimate suggests that significant disruption occurs when $M^{2}\\mbox{Rm} = O(1)$. To test our prediction, we analyse direct numerical simulations of vortices generated by the breakup of unstable shear flo...

  1. Frequency dependence of vestibuloocular reflex thresholds

    OpenAIRE

    Haburcakova, Csilla; Lewis, Richard F.; Merfeld, Daniel M.

    2011-01-01

    How the brain processes signals in the presence of noise impacts much of behavioral neuroscience. Thresholds provide one way to assay noise. While perceptual thresholds have been widely investigated, vestibuloocular reflex (VOR) thresholds have seldom been studied and VOR threshold dynamics have never, to our knowledge, been reported. Therefore, we assessed VOR thresholds as a function of frequency. Specifically, we measured horizontal VOR thresholds evoked by yaw rotation in rhesus monkeys, ...

  2. Wing pathology of white-nose syndrome in bats suggests life-threatening disruption of physiology

    Science.gov (United States)

    Cryan, Paul M.; Meteyer, Carol U.; Boyles, Justin G.; Blehert, David S.

    2010-01-01

    White-nose syndrome (WNS) is causing unprecedented declines in several species of North American bats. The characteristic lesions of WNS are caused by the fungus Geomyces destructans, which erodes and replaces the living skin of bats while they hibernate. It is unknown how this infection kills the bats. We review here the unique physiological importance of wings to hibernating bats in relation to the damage caused by G. destructans and propose that mortality is caused by catastrophic disruption of wing-dependent physiological functions. Mechanisms of disease associated with G. destructans seem specific to hibernating bats and are most analogous to disease caused by chytrid fungus in amphibians.

  3. Beam emittance and beam disruption

    International Nuclear Information System (INIS)

    Beam disruption during the collision of intense relativistic bunches has been studied by R. Hollebeek. In the case of oppositely charged bunches, focussing effects occur causing a decrease in the effective bunch cross section, and thereby an increase of luminosity by an enhancement factor H. The term disruption derives from the fact that the beam emittance changes markedly during the collision. 1 ref., 1 fig., 1 tab

  4. H-mode threshold power dependences in ITPA threshold database

    International Nuclear Information System (INIS)

    Newly contributed data and the current status of the International H-mode threshold database are presented. Selecting data from only one divertor geometry per tokamak leads to a reduction in the data scattering and improves the quality of the fits. The selection of a reduced set of transition types also leads to fit improvement. A new parameter, (R+a)/(R-a), is introduced in the power law scaling to account for the data provided by the spherical tokamaks. A prediction for ITER is given for the different power law scalings. Threshold power for ITER is estimated at about 35MW. (author)

  5. Health-related financial catastrophe, inequality and chronic illness in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Md Mizanur Rahman

    Full Text Available BACKGROUND: Bangladesh has a high proportion of households incurring catastrophic health expenditure, and very limited risk sharing mechanisms. Identifying determinants of out-of-pocket (OOP payments and catastrophic health expenditure may reveal opportunities to reduce costs and protect households from financial risk. OBJECTIVE: This study investigates the determinants of high healthcare expenditure and healthcare- related financial catastrophe. METHODS: A cross-sectional household survey was conducted in Rajshahi city, Bangladesh, in 2011. Catastrophic health expenditure was estimated separately based on capacity to pay and proportion of non-food expenditure. Determinants of OOP payments and financial catastrophe were estimated using double hurdle and Poisson regression models respectively. RESULTS: On average households spent 11% of their total budgets on health, half the residents spent 7% of the monthly per capita consumption expenditure for one illness, and nearly 9% of households faced financial catastrophe. The poorest households spent less on health but had a four times higher risk of catastrophe than the richest households. The risk of financial catastrophe and the level of OOP payments were higher for users of inpatient, outpatient public and private facilities respectively compared to using self-medication or traditional healers. Other determinants of OOP payments and catastrophic expenses were economic status, presence of chronic illness in the household, and illness among children and adults. CONCLUSION: Households that received inpatient or outpatient private care experienced the highest burden of health expenditure. The poorest members of the community also face large, often catastrophic expenses. Chronic illness management is crucial to reducing the total burden of disease in a household and its associated increased risk of level of OOP payments and catastrophic expenses. Households can only be protected from these situations by

  6. 2-(3-Methoxyphenyl)-5-methyl-1,8-naphthyridin-4(1H)-one (HKL-1) induces G2/M arrest and mitotic catastrophe in human leukemia HL-60 cells

    International Nuclear Information System (INIS)

    2-(3-Methoxyphenyl)-5-methyl-1,8-naphthyridin-4(1H)-one (HKL-1), a 2-phenyl-1,8-naphthyridin-4-one (2-PN) derivative, was synthesized and evaluated as an effective antimitotic agent in our laboratory. However, the molecular mechanisms are uncertain. In this study, HKL-1 was demonstrated to induce multipolar spindles, sustain mitotic arrest and generate multinucleated cells, all of which indicate mitotic catastrophe, in human leukemia HL-60 cells. Western blotting showed that HKL-1 induces mitotic catastrophe in HL-60 cells through regulating mitotic phase-specific kinases (down-regulating CDK1, cyclin B1, CENP-E, and aurora B) and regulating the expression of Bcl-2 family proteins (down-regulating Bcl-2 and up-regulating Bax and Bak), followed by caspase-9/-3 cleavage. These findings suggest that HKL-1 appears to exert its cytotoxicity toward HL-60 cells in culture by inducing mitotic catastrophe. Highlights: ► HKL-1 is a potential antimitotic agent against HL-60 cells. ► HKL-1 induces spindle disruption and sustained resulted in mitotic catastrophe. ► CENP-E and aurora B protein expressions significantly reduced. ► Bcl-2 family protein expressions altered and caspase-9/-3 activation. ► HKL-1 is an attractive candidate for possible use as a novel antimitotic agent.

  7. [Christopher Columbus flu. A hypothesis for an ecological catastrophe].

    Science.gov (United States)

    Muñoz-Sanz, Agustín

    2006-05-01

    When Christopher Columbus and his men embarked on the second Colombian expedition to the New World (1493), the crew suffered from fever, respiratory symptoms and malaise. It is generally accepted that the disease was influenza. Pigs, horses and hens acquired in Gomera (Canary Islands) traveled in the same ship. The pigs may well have been the origin of the flu and the intermediary hosts for genetic recombination of other viral subtypes. The Caribbean archipelago had a large population of birds, the natural reservoir of the avian influenza virus. In this ecological scenario there was a concurrence of several biological elements that had never before coexisted in the New World: pigs, horses, the influenza virus and humans. We propose that birds are likely to have played an important role in the epidemiology of the flu occurring on the second Colombian trip, which caused a fatal demographic catastrophe, with an estimated mortality of 90% among the natives. PMID:16762260

  8. Coupled catastrophes: sudden shifts cascade and hop among interdependent systems

    CERN Document Server

    Brummitt, Charles D; D'Souza, Raissa M

    2014-01-01

    A profoundly important challenge in several disciplines today is to understand how sudden changes can propagate among coupled systems. Examples include the synchronization of business cycles, population collapse in patchy ecosystems, markets shifting to a new technology platform, collapses in prices and in confidence in financial markets, and protests erupting in multiple countries. We characterize these phenomena using a simple model grounded in the theory of fast--slow ordinary differential equations and in catastrophe theory. In the model, a system consists of multiple subsystems (e.g., countries in the global economy or patches of an ecosystem), each described by a scalar quantity (such as economic output or population) that undergoes sudden changes via saddle-node bifurcations. The subsystems are coupled via their scalar quantities (e.g., trade couples economic output, diffusion couples populations); that coupling moves their bifurcations. The model elucidates two ways in which sudden changes can propaga...

  9. Industrial arsenic contamination causes catastrophic changes in freshwater ecosystems

    Science.gov (United States)

    Chen, Guangjie; Shi, Haibin; Tao, Jianshuang; Chen, Li; Liu, Yuanyuan; Lei, Guoliang; Liu, Xiaohai; Smol, John P.

    2015-11-01

    Heavy metal pollution is now widely recognized to pose severe health and environmental threats, yet much of what is known concerning its adverse impacts on ecosystem health is derived from short-term ecotoxicological studies. Due to the frequent absence of long-term monitoring data, little is known of the long-tem ecological consequences of pollutants such as arsenic. Here, our dated sediment records from two contaminated lakes in China faithfully document a 13.9 and 21.4-fold increase of total arsenic relative to pre-1950 background levels. Concurrently, coherent responses in keystone biota signal pronounced ecosystem changes, with a >10-fold loss in crustacean zooplankton (important herbivores in the food webs of these lake systems) and a >5-fold increase in a highly metal-tolerant alga. Such fundamental ecological changes will cascade through the ecosystem, causing potentially catastrophic consequences for ecosystem services in contaminated regions.

  10. Catastrophic chromosomal restructuring during genome elimination in plants.

    Science.gov (United States)

    Tan, Ek Han; Henry, Isabelle M; Ravi, Maruthachalam; Bradnam, Keith R; Mandakova, Terezie; Marimuthu, Mohan Pa; Korf, Ian; Lysak, Martin A; Comai, Luca; Chan, Simon Wl

    2015-01-01

    Genome instability is associated with mitotic errors and cancer. This phenomenon can lead to deleterious rearrangements, but also genetic novelty, and many questions regarding its genesis, fate and evolutionary role remain unanswered. Here, we describe extreme chromosomal restructuring during genome elimination, a process resulting from hybridization of Arabidopsis plants expressing different centromere histones H3. Shattered chromosomes are formed from the genome of the haploid inducer, consistent with genomic catastrophes affecting a single, laggard chromosome compartmentalized within a micronucleus. Analysis of breakpoint junctions implicates breaks followed by repair through non-homologous end joining (NHEJ) or stalled fork repair. Furthermore, mutation of required NHEJ factor DNA Ligase 4 results in enhanced haploid recovery. Lastly, heritability and stability of a rearranged chromosome suggest a potential for enduring genomic novelty. These findings provide a tractable, natural system towards investigating the causes and mechanisms of complex genomic rearrangements similar to those associated with several human disorders. PMID:25977984

  11. Eradicating Catastrophic Collapse in Interdependent Networks via Reinforced Nodes

    CERN Document Server

    Yuan, Xin; Stanley, H Eugene; Havlin, Shlomo

    2016-01-01

    In interdependent networks, it is usually assumed, based on percolation theory, that nodes become nonfunctional if they lose connection to the network giant component. However, in reality, some nodes, equipped with alternative resources, together with their connected neighbors can still be functioning once disconnected from the giant component. Here we propose and study a generalized percolation model that introduces a fraction of reinforced nodes in the interdependent networks that can function and support their neighborhood. We analyze, both analytically and via simulations, the order parameter$-$the functioning component$-$comprising both the giant component and smaller components that include at least one reinforced node. Remarkably, we find that for interdependent networks, we need to reinforce only a small fraction of nodes to prevent abrupt catastrophic collapses. Moreover, we find that the universal upper bound of this fraction is 0.1756 for two interdependent Erd\\H{o}s-R\\'{e}nyi (ER) networks, regula...

  12. Can non-ideal magnetohydrodynamics solve the magnetic braking catastrophe?

    CERN Document Server

    Wurster, James; Bate, Matthew R

    2015-01-01

    We investigate whether or not the low ionisation fractions in molecular cloud cores can solve the `magnetic braking catastrophe', where magnetic fields prevent the formation of circumstellar discs around young stars. We perform three-dimensional smoothed particle non-ideal magnetohydrodynamics (MHD) simulations of the gravitational collapse of one solar mass molecular cloud cores, incorporating the effects of ambipolar diffusion, Ohmic resistivity and the Hall effect alongside a self-consistent calculation of the ionisation chemistry assuming 0.1 micron grains. When including only ambipolar diffusion or Ohmic resistivity, discs do not form in the presence of strong magnetic fields, similar to the cases using ideal MHD. With the Hall effect included, disc formation depends on the direction of the magnetic field with respect to the rotation vector of the gas cloud. When the vectors are aligned, strong magnetic braking occurs and no disc is formed. When the vectors are anti-aligned, a disc with radius of 13AU ca...

  13. Catastrophe analysis on pillar instability considered mining effect

    Institute of Scientific and Technical Information of China (English)

    LI Jiang-teng; CAO Ping

    2005-01-01

    The instability of the pillar was discussed based on the potential energy principle and the cusp catastrophe theory, and a simplified mechanical model of the pillar was established considering the mining effect. The necessary-sufficient conditions, the jump value of displacement of pillar and the released energy expressions were deduced. The results show that the instability of the pillar is related to the properties of the rock, the external force and the relative stiffness of the elastic area to the plastic area. The instability of system is like to occur with the enlarging of the softening area or the decreasing of E/λ. The calculation done shows that the estimated results correspond to practical experience.

  14. CUSP CATASTROPHE MODEL OF INSTABILITY OF PILLAR IN ASYMMETRIC MINING

    Institute of Scientific and Technical Information of China (English)

    LI Jiang-teng; CAO Ping

    2005-01-01

    A simplified mechanical model of pillar-hang wall was established in asymmetric mining and instability of the system was discussed by means of potential energy principle and cusp catastrophe theory. The necessary-sufficient condition and the jump value of displacement of pillar and the released energy expressions were derived,which established foundation for quantifying of the instability of system. The results show that instability of the system is related to load and its stiffness distribution. The critical load increases with the increasing relative stiffness, and the system is more stable. On the contrary, the instability of system is likely to occur, and the released energy is larger in instability process, and the harm is more tremendous accordingly.Furthermore, an example was calculated, and the estimated results are in good agreement with the practical experience, which provide basis for mining order and arranging stope.

  15. Nuclear war and climatic catastrophe: Some policy implications

    International Nuclear Information System (INIS)

    Apocalyptic prediction require, to be taken seriously, higher standards of evidence than do assertions on other matters where the stakes are not as great. Since the immediate effects of even a single hermonuclear weapon explosion are so devastating, it is natural to assume - even without considering detailed mechanism - that the more or less simultaneous explosion of 10,000 such weapons all over the Northern Hemisphere might have unpredictable and catastrophic consequences. And yet, while it is widely accepted that a full nuclear war might mean the end of civilization at least in the Northern Hemisphere, claims that nuclear war might imply a reversion of the human population to prehistoric levels, or even the extinction of the human species, have, among some policymakers at least, been dismissed as alarmist or, worse, irrelevant

  16. Heckling the Catastrophe. On the Holocaust Literary Criticism

    Directory of Open Access Journals (Sweden)

    Paweł Wolski

    2015-01-01

    Full Text Available The article discusses a special kind of narrative about the catastrophe, treated as a specific genre of writing: the theory of literature of the Holocaust. The article presents its two most significant (although not the only ones features: firstly, the conviction about its unusual character as compared to other genres/forms of writing, sometimes secretly described by such concepts as the uniqueness of the Holocaust (which metonymizes not only the event itself but also the narrations referring to it and, secondly, identifies all text-producing entities (narrator, author etc., simultaneously constituting the basic feature of the most important genre/modality of this kind of writing which is testimony. The article presents the examples of Polish and foreign scholars portraying this state of affairs.

  17. Catastrophes in nature and society mathematical modeling of complex systems

    CERN Document Server

    Khlebopros, Rem G; Fet, Abram I

    2007-01-01

    Many people are concerned about crises leading to disasters in nature, in social and economic life. The book offers a popular account of the causative mechanisms of critical states and breakdown in a broad range of natural and cultural systems - which obey the same laws - and thus makes the reader aware of the origin of catastrophic events and the ways to avoid and mitigate their negative consequences. The authors apply a single mathematical approach to investigate the revolt of cancer cells that destroy living organisms and population outbreaks that upset natural ecosystems, the balance between biosphere and global climate interfered lately by industry, the driving mechanisms of market and related economic and social phenomena, as well as the electoral system the proper use of which is an arduous accomplishment of democracy.

  18. Cylinder on an incline as a fold catastrophe system

    International Nuclear Information System (INIS)

    The motion of a cylinder on an inclined plane, acted upon by a torque along its axis, is studied theoretically and experimentally. It is shown that the potential for the centre-of-mass exhibits the features of a fold catastrophe potential, the control parameter being related to the strength of the torque. This parameter determines whether or not the system experiences stable equilibrium positions. If it does, and depending on the initial conditions, it may perform oscillations around an equilibrium position, or it may cross a no-return point and roll down. A cylinder with a magnet inside, placed on an inclined plane in a region where a uniform magnetic field is present, is a real example of such a system. We constructed that system and report the data obtained in a set of experiments

  19. Surviving protein quality control catastrophes--from cells to organisms.

    Science.gov (United States)

    Schneider, Kim; Bertolotti, Anne

    2015-11-01

    Organisms have evolved mechanisms to cope with and adapt to unexpected challenges and harsh conditions. Unfolded or misfolded proteins represent a threat for cells and organisms, and the deposition of misfolded proteins is a defining feature of many age-related human diseases, including the increasingly prevalent neurodegenerative diseases. These protein misfolding diseases are devastating and currently cannot be cured, but are hopefully not incurable. In fact, the aggregation-prone and potentially harmful proteins at the origins of protein misfolding diseases are expressed throughout life, whereas the diseases are late onset. This reveals that cells and organisms are normally resilient to disease-causing proteins and survive the threat of misfolded proteins up to a point. This Commentary will outline the limits of the cellular resilience to protein misfolding, and discuss the possibility of pushing these limits to help cells and organisms to survive the threat of misfolding proteins and to avoid protein quality control catastrophes. PMID:26483388

  20. Vegetative disthonic syndrome treatment in children, suffered from Chernobyl catastrophe

    International Nuclear Information System (INIS)

    Vegetative diatonic syndrome was diagnosed in 28,3% of children, arrived to sanatorium from the regions, suffered from Chernobyl catastrophe. In order to make correction of this kind of pathology 62 children had undergone the treatment on the base of specially developed programs: 1-st - complex of spirulina reception, infrared radiation treatment, collar-neck zone massage, 2-nd - glycine reception and collar-neck zone massage, 3-d - short wave frequency therapy on active points (control group - 37 children). As the result, in children of the main group in comparison with control, for certain decreased somatic complains quantity (p=0,008), neurological state (p=0,0009) and autonomic system state (p=0,05) improved. Thus the suggested complexes exert gentle influence upon mane autonomic system characteristics and promote subsidence of clinical manifestation of the vegetative diatonic syndrome. (Authors)

  1. Alternative solutions for public and private catastrophe funding in Austria

    Directory of Open Access Journals (Sweden)

    M. Gruber

    2008-07-01

    Full Text Available The impacts of natural hazards as well as their frequency of occurrence during the last decades have increased decisively. Therefore, the public as well as the private sector are expected to react to this development by providing sufficient funds, in particular for the improvement of protection measures and an enhanced funding of damage compensation for affected private individuals, corporate and public entities.

    From the public stance, the establishment of an appropriate regulatory environment seems to be indispensable. Structural and legal changes should, on the one hand, renew and improve the current distribution system of public catastrophe funds as well as the profitable investment of these financial resources, and on the other hand, facilitate the application of alternative mechanisms provided by the capital and insurance markets.

    In particular, capital markets have developed alternative risk transfer and financing mechanisms, such as captive insurance companies, risk pooling, contingent capital solutions, multi-trigger products and insurance securitisation for hard insurance market phases. These instruments have already been applied to catastrophic (re-insurance in other countries (mainly the US and off-shore domiciles, and may contribute positively to the insurability of extreme weather events in Austria by enhancing financial capacities. Not only private individuals and corporate entities may use alternative mechanisms in order to retain, thus, to finance certain risks, but also public institutions.

    This contribution aims at analysing potential solutions for an improved risk management of natural hazards in the private and the public sector by considering alternative mechanisms of the capital and insurance markets. Also the establishment of public-private-partnerships, which may contribute to a more efficient cat funding system in Austria, is considered.

  2. Overcoming challenges of catastrophe modelling in data poor regions

    Science.gov (United States)

    Grassby, L.; Millinship, I.; Breinl, K.

    2012-04-01

    There is an increasing demand for loss accumulation tools in expanding international insurance markets such as India, China and Thailand. This reflects the combination of an increase in exposures in these territories as industry intensifies and urban development expands, as well as several notable natural catastrophes affecting these areas over the past few years (e.g. extreme floods in Mumbai in 2006 and in Thailand in 2011). Large, global insurers and reinsurers are embracing the opportunity to underwrite these exposures but only where adequate tools are available to provide understanding of the hazards, exposures and potential losses. Unlike more developed countries, data availability in these regions is typically limited and of poor resolution, but model development is still required in order to analyse the risk. Some of the modelling challenges associated with data limitations include: (1) dealing with a lack of hydrological data which results in greater uncertainty of the flow rate and event frequency; (2) lower DTM resolution than that available across much of Europe, which underlies the hazard component of the catastrophe model; (3) limited accessibility to data that characterises the Built Environment including information on different building types and their susceptibility to damage; and (4) a lack of claims data from previous events or engineering research into the vulnerability of different building types. This is used to generate of country and structure specific vulnerability curves that explain the relationship between hazard intensity and damages. By presenting an industry specific flood model for data-poor India in collaboration with Allianz Re, we illustrate how we have overcome many of these challenges to allow loss accumulations to be made. The resulting model was successfully validated against the floods in Mumbai and Surat in 2006 and is being developed further with the availability of new data.

  3. The Chernobyl catastrophe is the most terrible civil nuclear incident

    International Nuclear Information System (INIS)

    Full text: The 4th nuclear reactor of the Chernobyl NPP exploded on 26 April 1986, 20 years ago. It's the most terrible nuclear civil accident of all times. The consequences of the Chernobyl accident led to contamination of 3,1 million ha of arable land, 1,5 million ha of natural pasture land, 3,5 million ha of forests and changed the lifestyle for millions of people in Belarus, Ukraine and Russia. It is well known that the mortality in the contaminated areas (infant mortality by cancer) drastically increased. The Chernobyl catastrophe is presented , such as a sad example for humanity, a complex political international, economical, social and, particular, ecological problem according to the traditional and new studies for the development of the nucleotide contaminated territories: 1. Financing of safety of stopped working 4th nuclear reactor (security of covering system) and of work another 3 blocks at the Chernobyl NPP. Detailed control of international financial support for guarantee the safety, security of the Chernobyl NPP and sustainable development for rehabilitation of the affected zones and people. 2. It should be marked increase in medical, demographic analysis and in social, economical protection of the people in the contaminated areas. 3. Analysis and synthesis, monitoring of the long-time data results due to environmental, ecological, social and political consequences of the Chernobyl disaster. 4. Protection from the possible terrorist (extra) actions and (inter) damage or incident function of the Chernobyl plant, such as an old generation nuclear power. 5. Planned budget for future studies in the affected territories and flexibility actually realization of budget (State and International). 6. Nuclear refuse and aria/water protection in the Ukraine, Belarus and Russia contaminated zones. 7. Risk evaluation of not good function of NPPs which are situated in Russia, Ukraine and in another places (always remembering that the Chernobyl catastrophe is the

  4. Alternative solutions for public and private catastrophe funding in Austria

    Science.gov (United States)

    Gruber, M.

    2008-07-01

    The impacts of natural hazards as well as their frequency of occurrence during the last decades have increased decisively. Therefore, the public as well as the private sector are expected to react to this development by providing sufficient funds, in particular for the improvement of protection measures and an enhanced funding of damage compensation for affected private individuals, corporate and public entities. From the public stance, the establishment of an appropriate regulatory environment seems to be indispensable. Structural and legal changes should, on the one hand, renew and improve the current distribution system of public catastrophe funds as well as the profitable investment of these financial resources, and on the other hand, facilitate the application of alternative mechanisms provided by the capital and insurance markets. In particular, capital markets have developed alternative risk transfer and financing mechanisms, such as captive insurance companies, risk pooling, contingent capital solutions, multi-trigger products and insurance securitisation for hard insurance market phases. These instruments have already been applied to catastrophic (re-)insurance in other countries (mainly the US and off-shore domiciles), and may contribute positively to the insurability of extreme weather events in Austria by enhancing financial capacities. Not only private individuals and corporate entities may use alternative mechanisms in order to retain, thus, to finance certain risks, but also public institutions. This contribution aims at analysing potential solutions for an improved risk management of natural hazards in the private and the public sector by considering alternative mechanisms of the capital and insurance markets. Also the establishment of public-private-partnerships, which may contribute to a more efficient cat funding system in Austria, is considered.

  5. Applying Catastrophe Theory to an Information-Processing Model of Problem Solving in Science Education

    Science.gov (United States)

    Stamovlasis, Dimitrios; Tsaparlis, Georgios

    2012-01-01

    In this study, we test an information-processing model (IPM) of problem solving in science education, namely the working memory overload model, by applying catastrophe theory. Changes in students' achievement were modeled as discontinuities within a cusp catastrophe model, where working memory capacity was implemented as asymmetry and the degree…

  6. Pain-related catastrophizing in pain patients and people with pain in the general population.

    NARCIS (Netherlands)

    Boer, M.J. de; Struys, M.M.; Versteegen, G.J.

    2012-01-01

    BACKGROUND: Catastrophizing is a defining factor in the pain experience and strongly contributes to the prediction of various aspects of health. Catastrophizing is not just present in pain patients, but may also be present in people with non-clinical pain. The aim of the present study is to investig

  7. Pain-related catastrophizing in pain patients and people with pain in the general population

    NARCIS (Netherlands)

    de Boer, M. J.; Struys, M. M. R. F.; Versteegen, G. J.

    2012-01-01

    Background Catastrophizing is a defining factor in the pain experience and strongly contributes to the prediction of various aspects of health. Catastrophizing is not just present in pain patients, but may also be present in people with non-clinical pain. The aim of the present study is to investiga

  8. Research on traffic flow forecasting model based on cusp catastrophe theory

    Institute of Scientific and Technical Information of China (English)

    张亚平; 裴玉龙

    2004-01-01

    This paper intends to describe the relationship between traffic parameters by using cusp catastrophe theory and to deduce highway capacity and corresponding speed forecasting value through suitable transformation of catastrophe model. The five properties of a catastrophe system are outlined briefly, and then the data collected on freeways of Zhujiang River Delta, Guangdong province, China are examined to ascertain whether they exhibit qualitative properties and attributes of the catastrophe model. The forecasting value of speed and capacity for freeway segments are given based on the catastrophe model. Furthermore, speed-flow curve on freeway is drawn by plotting out congested and uncongested traffic flow and the capacity value for the same freeway segment is also obtained from speed-flow curve to test the feasibility of the application of cusp catastrophe theory in traffic flow analysis. The calculating results of catastrophe model coincide with those of traditional traffic flow models regressed from field observed data, which indicates that the deficiency of traditional analysis of relationship between speed, flow and occupancy in two-dimension can be compensated by analysis of the relationship among speed, flow and occupancy based on catastrophe model in three-dimension. Finally, the prospects and problems of its application in traffic flow research in China are discussed.

  9. Analysis of Interlayer Connection Catastrophe Characteristics in Internet AS level Topology

    Directory of Open Access Journals (Sweden)

    Si-yuan Jia

    2013-02-01

    Full Text Available Based on CAIDA’s (cooperative association for Internet data analysis statistics at AS-level collected from April 2009 to April 2010, it is found that network size, degree correlations and clustering have changed significantly three times. According to the definition of k-core, the Internet topology is divided into different levels. In this paper, by analyzing the changing connection on each level at the three time spots, we found that the connection difference between the highest and the lowest level varies cyclically. Before Internet has significant change, the connection difference between the highest and the lowest shell changes acutely. At that time point it is the later stage of the fluctuation period which is the accumulation of small fluctuation. The concept of catastrophe coefficient is proposed for quantifying the probability of Internet catastrophe so that the catastrophe coefficient of Internet could be calculated on real time, and the catastrophe time spots could be predicted. Using real data for verification, it turns out that catastrophe coefficient can accurately predict the "giant fluctuations" occurrence in the macroscopic structure. With the proposal of the concept of catastrophe coefficient, the research can play an important guiding role in understanding the actual network internal development and changes, analyzing the cause of Internet catastrophe, preventing devastating catastrophe, planning and further re-designing Ipv6.

  10. Household Catastrophic Healthcare Expenditure and Impoverishment Due to Rotavirus Gastroenteritis Requiring Hospitalization in Malaysia

    OpenAIRE

    Loganathan, T; Lee, WS; Lee, KF; Jit, M.; Ng, CW

    2015-01-01

    Background While healthcare costs for rotavirus gastroenteritis requiring hospitalization may be burdensome on households in Malaysia, exploration on the distribution and catastrophic impact of these expenses on households are lacking. Objectives We assessed the economic burden, levels and distribution of catastrophic healthcare expenditure, the poverty impact on households and inequities related to healthcare payments for acute gastroenteritis requiring hospitalization in Malaysia. Methods A...

  11. 12 CFR 741.214 - Report of crime or catastrophic act and Bank Secrecy Act compliance.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Report of crime or catastrophic act and Bank Secrecy Act compliance. 741.214 Section 741.214 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION... Unions § 741.214 Report of crime or catastrophic act and Bank Secrecy Act compliance. Any credit...

  12. Managing Catastrophic Disaster Risks Using Alternative Risk financing and Pooled Insurance Structures

    OpenAIRE

    Pollner, John D

    2001-01-01

    This report examines the constraints and opportunities in implementing a catastrophe insurance system which can resolve the key obstacles impeding broader implementation of a risk funding approach. The four main pillars in such a strategy involve: 1) strengthening insurance sector regulatory requirements and supervision; 2) establishing broad-based pooled catastrophe funding structures wit...

  13. Baryon Form Factors at Threshold

    Energy Technology Data Exchange (ETDEWEB)

    Baldini Ferroli, Rinaldo [Museo Storico della Fisica e Centro Studi e Ricerche ' E. Fermi' , Rome (Italy); INFN, Laboratori Nazionali di Frascati, Frascati (Italy); Pacetti, Simone [INFN and Dipartimento di Fisica, Universita di Perugia, Perugia (Italy)

    2012-04-15

    An extensive study of the e{sup +}e{sup -}{yields}pp{sup Macron }BABAR cross section data is presented. Two unexpected outcomes have been found: the modulus of the proton form factor is normalized to one at threshold, i.e.: |G{sup p}(4M{sub p}{sup 2})|=1, as a pointlike fermion, and the resummation factor in the Sommerfeld formula is not needed. Other e{sup +}e{sup -} {yields} baryon-antibaryon cross sections show a similar behavior near threshold.

  14. Hypergraphs with Zero Chromatic Threshold

    OpenAIRE

    Balogh, József; Lenz, John

    2013-01-01

    Let F be an r-uniform hypergraph. The chromatic threshold of the family of F-free, r-uniform hypergraphs is the infimum of all non-negative reals c such that the subfamily of F-free, r-uniform hypergraphs H with minimum degree at least $c \\binom{|V(H)|}{r-1}$ has bounded chromatic number. The study of chromatic thresholds of various graphs has a long history, beginning with the early work of Erd\\H{o}s-Simonovits. One interesting question, first proposed by \\L{}uczak-Thomass\\'{e} and then solv...

  15. Yoga attitudes in chronic low back pain: Roles of catastrophizing and fear of movement.

    Science.gov (United States)

    Combs, Martha A; Thorn, Beverly E

    2015-08-01

    Chronic low back pain is a significant public health problem and, although underused, yoga may be an effective complementary treatment. The current study examined associations of pain catastrophizing and fear of movement with attitudes toward yoga in adults with chronic low back pain. Participants completed three quantitative questionnaires assessing specific constructs: beliefs about yoga, fear of movement, and pain catastrophizing. A semi-structured in-person interview was then conducted to obtain specific pain-related information. Hierarchical regression and mediational analyses were used to test hypotheses. Consistent with the fear-avoidance model of chronic pain, catastrophizing and fear of movement were negatively associated with yoga attitudes. Specifically, fear of movement was a mediator between catastrophizing and attitudes toward yoga. Individuals with higher levels of catastrophizing and fear of movement may be less likely to consider a pain treatment involving physical movement. PMID:26256134

  16. Gérard Brugnot, 2008, Les Catastrophes Naturelles, Paris, Le Cavalier Bleu, 127 p.

    Directory of Open Access Journals (Sweden)

    Stéphane Callens

    2009-01-01

    Full Text Available La collection « idées reçues » se propose de faire le point sur les savoirs et les croyances à propos d’un thème donné. Le thème des « catastrophes naturelles » est présenté par Gérard Brugnot, qui commente 16 idées reçues sur ces risques majeurs, regroupées dans quatre chapitres : 1/ « il y a toujours eu des catastrophes naturelles, il y en aura toujours », 2/ « Des catastrophes vraiment toutes naturelles ? », 3/ « On peut réduire les effets des catastrophes naturelles », 4/ « Catastrophes n...

  17. Disruptive event analysis: volcanism and igneous intrusion

    International Nuclear Information System (INIS)

    Three basic topics are addressed for the disruptive event analysis: first, the range of disruptive consequences of a radioactive waste repository by volcanic activity; second, the possible reduction of the risk of disruption by volcanic activity through selective siting of a repository; and third, the quantification of the probability of repository disruption by volcanic activity

  18. Disruption studies on ASDEX upgrade

    International Nuclear Information System (INIS)

    Disruptions generate large thermal and mechanical stresses on the tokamak components and are occasionally responsible for damages to the machine. For a future reactor disruptions have a significant impact on the design since all loading conditions must be analyzed in accordance with stricter design criteria (due to safety or difficult maintenance). Therefore the uncertainties affecting the predicted stresses must be reduced as much as possible with a more comprehensive set of measurements and analyses in this generation of experimental machines, and avoidance/predictive methods must be developed further. Disruption studies on ASDEX Upgrade are focused on these subjects, namely on: (1) understanding the physical mechanisms leading to this phenomenon in order to learn to avoid it or to predict its occurrence and to mitigate its effects; (2) analyzing the effects of disruptions on the machine to determine the functional dependence of the thermal and mechanical loads upon the discharge parameters. This allows, firstly, to dimension or reinforce the machine components to withstand these loads and, secondly, to extrapolate them to tokamaks still in the design phase; (3) learning to mitigate the consequence of disruptions, i.e. thermal loads, mechanical forces and runaways with injection of impurity pellets or gas. This paper is focused on most recent results concerning points, i.e. on the analysis of the degree of asymmetry of the forces and on the use of impurity puff for mitigation

  19. Disruption studies in ASDEX Upgrade

    International Nuclear Information System (INIS)

    Disruption generate large thermal and mechanical stresses on the tokamak components. For a future reactor disruptions have a significant impact on the design since all loading conditions must be analyzed in accordance with stricter design criteria (due to safety or difficult maintenance). Therefore the uncertainties affecting the predicted stresses must be reduced as much as possible with a more comprehensive set of measurements and analyses in this generation of experimental machines, and avoidance/ predictive methods must be developed further. The study of disruptions on ASDEX Upgrade is focused on these subjects, namely on: (1) understanding the physical mechanisms leading to this phenomenon and learning to avoid it or to predict its occurrence (with neural networks, for example) and to mitigate its effects; (2) analyzing the effects of disruptions on the machine to determine the functional dependence of the thermal and mechanical loads upon the discharge parameters. This allows to dimension or reinforce the machine components to withstand these loads and to extrapolate them to tokamaks still in the design phase; (3) learning to mitigate the consequence of disruptions. (author)

  20. Weights of Exact Threshold Functions

    DEFF Research Database (Denmark)

    Babai, László; Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.;

    2010-01-01

    We consider Boolean exact threshold functions defined by linear equations, and in general degree d polynomials. We give upper and lower bounds on the maximum magnitude (absolute value) of the coefficients required to represent such functions. These bounds are very close and in the linear case in ...

  1. Quark States Near a Threshold

    CERN Document Server

    Bashinsky, S V

    1996-01-01

    We reduce the problem of many-channel hadron scattering at nonrelativistic energies to calculations on the scale of a few fermis. Having thus disentangled kinematics from interior quark dynamics, we study their interplay when a quark state occurs near a hadronic threshold. Characteristic parameters, such as the observed peak width, the decay width, and the shape of a cross-section itself are highly affected by the threshold. A general pole-form expression for the S-matrix in an arbitrary background is given, and the pole structure of S is examined. We show that at a hadronic threshold two poles in S are generally important. We also classify the S-matrix pole structure considering an example where nonsingular coupled channels are closed at the threshold. The framework of our paper is the P-matrix formalism, which is reviewed and extended for use together with conventional methods of computing quark-gluon dynamics. Results and applications are illustrated for the doubly strange two-baryon system, the detailed a...

  2. Crossing Thresholds in Academic Reading

    Science.gov (United States)

    Abbott, Rob

    2013-01-01

    This paper looks at the conceptual thresholds in relation to academic reading which might be crossed by undergraduate English Literature students. It is part of a wider study following 16 students through three years of undergraduate study. It uses theoretical ideas from Bakhtin and Foucault to analyse interviews with English lecturers. It…

  3. The Nature of Psychological Thresholds

    NARCIS (Netherlands)

    Rouder, Jeffrey N.; Morey, Richard D.

    2009-01-01

    Following G. T. Fechner (1966), thresholds have been conceptualized as the amount of intensity needed to transition between mental states, such as between a states of unconsciousness and consciousness. With the advent of the theory of signal detection, however, discrete-state theory and the correspo

  4. Catastrophic caldera-forming eruptions II: The subordinate role of magma buoyancy as an eruption trigger

    Science.gov (United States)

    Gregg, Patricia M.; Grosfils, Eric B.; de Silva, Shanaka L.

    2015-10-01

    Recent analytical investigations have suggested that magma buoyancy is critical for triggering catastrophic caldera forming eruptions. Through detailed assessment of these approaches, we illustrate how analytical models have been misapplied for investigating buoyancy and are, therefore, incorrect and inconclusive. Nevertheless, the hypothesis that buoyancy is the critical trigger for larger eruptions warrants further investigation. As such, we utilize viscoelastic finite element models that incorporate buoyancy to test overpressure evolution and mechanical failure in the roof due to the coalescence of large buoyant magma bodies for two model cases. In the first case, we mimic empirical approaches and include buoyancy as an explicit boundary condition. In the second set of models, buoyancy is calculated implicitly due to the density contrast between the magma in the reservoir and the host rock. Results from these numerical experiments indicate that buoyancy promotes only minimal overpressurization of large silicic magma reservoirs (implementations and the results from the numerical experiments, we conclude that buoyancy does not provide an eruption triggering mechanism for large silicic systems. Therefore, correlations of buoyancy with magma residence times, the eruption frequency-volume relationship, and the dimensions of calderas are re-assessed. We find a causal relationship with magma reservoir volume that implicates the mechanical conditions of the host rock as a primary control on eruption frequency. As magma reservoirs grow in size (> 100 km3) they surpass a rheological threshold where their subsequent evolution is controlled by host rock mechanics. Consequently, this results in a thermomechanical division between small systems that are triggered "internally" by magmatic processes and large systems that are triggered "externally" by faulting related to roof uplift or tectonism. Finally, critical assessment of recent analytical approaches illustrates that care

  5. National Health Insurance Scheme: How Protected Are Households in Oyo State, Nigeria from Catastrophic Health Expenditure?

    Directory of Open Access Journals (Sweden)

    Olayinka Stephen Ilesanmi

    2014-05-01

    Full Text Available Background The major objective of the National Health Insurance Scheme (NHIS in Nigeria is to protect families from the financial hardship of large medical bills. Catastrophic Health Expenditure (CHE is rampart in Nigeria despite the take-off of the NHIS. This study aimed to determine if households enrolled in the NHIS were protected from having CHE. Methods The study took place among 714 households in urban communities of Oyo State. CHE was measured using a threshold of 40% of monthly non-food expenditure. Descriptive statistics were done, Principal Component Analysis was used to divide households into wealth quintiles. Chi-square test and binary logistic regression were done. Results The mean age of household respondent was 33.5 years. The median household income was 43,500 naira (290 US dollars and the range was 7,000–680,000 naira (46.7–4,533 US dollars in 2012. The overall median household healthcare cost was 890 naira (5.9 US dollars and the range was 10-17,700 naira (0.1–118 US dollars in 2012. In all, 67 (9.4% households were enrolled in NHIS scheme. Healthcare services was utilized by 637 (82.9% and CHE occurred in 42 (6.6% households. CHE occurred in 14 (10.9% of the households in the lowest quintile compared to 3 (2.5% in the highest wealth quintile (P= 0.004. The odds of CHE among households in lowest wealth quintile is about 5 times. They had Crude OR (CI: 4.7 (1.3–16.8, P= 0.022. Non enrolled households were two times likely to have CHE, though not significant Conclusion Households in the lowest wealth quintiles were at higher risk of CHE. Universal coverage of health insurance in Nigeria should be fast-tracked to give the expected financial risk protection and decreased incidence of CHE.

  6. Major disruptions, inverse cascades, and the Strauss equations

    International Nuclear Information System (INIS)

    Current-carrying plasmas in a strong dc magnetic field are subject to violent disruptions above certain thresholds. At present difficult to verify, explanations are typically sought in terms of tearing modes. An alternative explanation is in terms of inverse magnetic helicity cascades, generated from a variety of possible sources of small-scale MHD turbulence. Strongly anisotropic MHD plasmas may be described by the Strauss equations. Indications of turbulent inverse cascade behavior for the Strauss equations are sought, in parallel with earlier examples from MHD and fluid mechanics

  7. Nuclear catastrophe in Japan. Health consequences resulting from Fukushima

    International Nuclear Information System (INIS)

    On 11 March 2011, a nuclear catastrophe occurred at the Fukushima Dai-ichi nuclear power plant in Japan in the wake of an earthquake and due to serious safety deficiencies. This resulted in a massive and prolonged release of radioactive fission and decay products. Approximately 20% of the radioactive substances released into the atmosphere have led to the contamination of the landmass of Japan with 17,000 becquerels per square meter of cesium-137 and a comparable quantity of cesium-134. The initial health consequences of the nuclear catastrophe are already now, after only two years, scientifically verifiable. Similar to the case of Chernobyl, a decline in the birth rate was documented nine months after the nuclear catastrophe. Throughout Japan, the total drop in number of births in December 2011 was 4362, with the Fukushima Prefecture registering a decline of 209 births. Japan also experienced a rise in infant mortality, with 75 more children dying in their first year of life than expected statistically. In the Fukushima Prefecture alone, some 55,592 children were diagnosed with thyroid gland nodules or cysts. In contrast to cysts and nodules found in adults, these findings in children must be classified as precancerous. There were also the first documented cases in Fukushima of thyroid cancer in children. The present document undertakes three assessments of the expected incidence of cancer resulting from external exposure to radiation. These are based on publications in scientific journals on soil contamination in 47 prefectures in Japan, the average total soil contamination, and, in the third case, on local dose rate measurements in the fall of 2012. Taking into consideration the shielding effect of buildings, the medical organization IPPNW has calculated the collective lifetime doses for individuals at 94,749 manSv, 206,516 manSv, and 118,171 manSv, respectively. In accordance with the risk factors set by the European Committee on Radiation Risk (ECRR) for death

  8. Dynamic Sublimation Pressure and the Catastrophic Breakup of Comet ISON

    CERN Document Server

    Steckloff, Jordan K; Bowling, Timothy; Melosh, H Jay; Minton, David; Lisse, Carey M; Battams, Karl

    2015-01-01

    Previously proposed mechanisms have difficulty explaining the disruption of Comet C/2012 S1 (ISON) as it approached the Sun. We describe a novel cometary disruption mechanism whereby comet nuclei fragment and disperse through dynamic sublimation pressure, which induces differential stresses within the interior of the nucleus. When these differential stresses exceed its material strength, the nucleus breaks into fragments. We model the sublimation process thermodynamically and propose that it is responsible for the disruption of Comet ISON. We estimate the bulk unconfined crushing strength of Comet ISON's nucleus and the resulting fragments to be 0.5 Pa and 1-9 Pa respectively, assuming typical Jupiter Family Comet (JFC) albedos. However, if Comet ISON has an albedo similar to Pluto, this strength estimate drops to 0.2 Pa for the intact nucleus and 0.6-4 Pa for its fragments. Regardless of assumed albedo, these are similar to previous strength estimates of JFCs. This suggests that, if Comet ISON is representat...

  9. Is heat pain detection threshold associated with the area of secondary hyperalgesia following brief thermal sensitization?

    DEFF Research Database (Denmark)

    Hansen, Morten Sejer; Wetterslev, Jørn; Pipper, Christian Bressen;

    2016-01-01

    investigates different aspects of the human pain response. Brief thermal sensitization induces a mild burn injury, resulting in development of primary hyperalgesia at the site of stimulation, and secondary hyperalgesia surrounding the site of stimulation. Central sensitization is believed to play an important...... role in the development of secondary hyperalgesia; however, a possible association of secondary hyperalgesia following brief thermal sensitization and other heat pain models remains unknown. Our aim with this study is to investigate how close the heat pain detection threshold is associated with the......) heat pain detection threshold and iii) pain during thermal stimulation. Additionally, the participants will be tested with the Pain Catastrophizing Scale and Hospital Anxiety and Depression Scale questionnaires. We conducted statistical simulations based on data from our previous study, to estimate an...

  10. Reassessing Catastrophic Infill of the Pokhara Valley, Nepal Himalaya

    Science.gov (United States)

    Schwanghart, Wolfgang; Bernhardt, Anne; Stolle, Amelie; Adhikari, Basantha; Korup, Oliver

    2014-05-01

    The Pokhara valley, home to Nepal's second largest city and a major tourist attraction (28°15'N, 83°58'E), is covered by 4-5 km3 and 50-100 m thick intramontane fan deposits that resulted from massive aggradation of the Seti Khola, a river draining the Annapurna Massif of the Greater Himalaya. Poorly sorted, gravelly fluvial facies intercalated with debris-flow and mud-flow facies known as the Pokhara Gravels attest to highly energetic transport conditions during one or several catastrophic flow events. In May 2012, a devastative flash flood/debris flow in the Seti Khola rekindled interest in the formation processes and timing of the Pokhara Gravels as they may provide constraints on the magnitudes and frequencies of similar past events. Interpretations of previous sedimentological work and radiocarbon dating (Yamanaka, 1982; Fort, 1987) culminated in the belief that the Pokhara Gravels were catastrophically emplaced only 500 to 1000 years ago, although the exact nature, timing, and triggers of the purported event(s) remain obscure. Specifically, it remains debated whether the Pokhara Gravels were deposited instantaneously, possibly within less than a year, or whether sedimentation was more protracted over perhaps decades to millennia. We present new geomorphological, sedimentological, geochemical, and radiocarbon data and re-assess a potential catastrophic infill of the Pokhara Valley during one or several high-magnitude events. Support for this scenario is given by laterally continuous long-runout (~40 km) debris-flow deposits topped by large (i.e. up to >11-m) boulders, a distinctly calcareous lithology diagnostic of a small Greater Himalayan source area tens of kilometres upstream, and by historical anecdotes of a large flood that destroyed an earlier settlement in the area. However, we show that dated outcrops of fine-grained sediments in tributaries blocked by the Pokhara Gravels yield asynchronous ages. Although our radiocarbon dates are consistent with

  11. Gravothermal catastrophe in the framework of f(R) gravity

    International Nuclear Information System (INIS)

    Full text: The anomalous rotation curves of spiral galaxies, the mass discrepancy in elliptical galaxies as well as in clusters of galaxies, are all well known observational aspects that led to the necessity of considering huge amounts of the so called dark matter at a galactic and extra-galactic scale. Relative to the mass discrepancy in the elliptical and in clusters of galaxies, the total mass can be estimated in two ways: I) by taking into account the motion of its members, the virial theorem provides MV , the so called virial mass; II) considering the total sum of each individual member's mass one may estimate the total baryonic mass MB. The mass discrepancy then arises when one verifies that MV is considerably greater than MB, typical values are MV / MB ∼ 20 - 30. There is nowadays a great debate about the mechanism behind this observed mass discrepancy. As long as the possibility that Einstein's and Newton's theories of gravity breaks down at galactic scale can not be excluded a priori, a number of galactic environment scenarios and modified gravity have been proposed in the literature. Perhaps the much simple of these models, f(R) gravity examines the possibility of modifying Einstein's general relativity by adding terms proportional to powers of the Ricci scalar R to the Einstein-Hilbert Lagrangian. Specific models of f(R) gravity were already examined in the literature which can explain the Pioneer anomaly and the flat rotation curves of spiral galaxies. As specified above, the virial theorem is in the core of the observed mass discrepancy. However, when one consider the virial theorem in the framework of f(R) gravity, supplementary geometric terms arise in the generalized Einstein's equations providing an effective contribution to the gravitational energy. Here we investigate how the total virial mass, which is proportional to the effective mass associated with the new geometrical term, affects the so called gravothermal catastrophe in the context of f

  12. Gravothermal catastrophe in the framework of f(R) gravity

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Thiago B.R.F.; Santos, Janilo [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

    2011-07-01

    , affects the so called gravothermal catastrophe in the context of f(R) gravity. As is well known, the thermodynamics of self-gravitating systems shows a stable branch for negative specific heat, a phenomenon known as gravothermal catastrophe. This can be derived from the virial theorem applied to astrophysical systems and has important consequences for the stability of nuclear burning in the cores of stars. (author)

  13. The issue of threshold states

    International Nuclear Information System (INIS)

    The states which have not joined the Non-proliferation Treaty nor have undertaken any other internationally binding commitment not to develop or otherwise acquire nuclear weapons are considered a threshold states. Their nuclear status is rendered opaque as a conscious policy. Nuclear threshold status remains a key disarmament issue. For those few states, as India, Pakistan, Israel, who have put themselves in this position, the security returns have been transitory and largely illusory. The cost to them, and to the international community committed to the norm of non-proliferation, has been huge. The decisions which could lead to recovery from the situation in which they find themselves are essentially at their own hands. Whatever assistance the rest of international community is able to extend, it will need to be accompanied by a vital political signal

  14. Hadronic resonances enhanced by thresholds

    CERN Document Server

    Caramés, T F

    2016-01-01

    We present a neat example of a meson--baryon system where the vicinity of two different thresholds enhances the binding of a hadronic resonance, a pentaquark. As a consequence the pattern of states may change when moving among different flavor sectors, what poses a warning on naive extrapolations to heavy flavor sectors based on systematic expansions. For this purpose we simultaneously analyze the $N\\bar D$ and $NB$ two-hadron systems looking for possible bound states or resonances. When a resonance is controlled by a coupled-channel effect, going to a different flavor sector may enhance or diminish the binding. This effect may, for example, generate significant differences between the charmonium and bottomonium spectra above open-flavor thresholds or pentaquark states in the open-charm and open-bottom sectors.

  15. Pion production reaction near threshold

    International Nuclear Information System (INIS)

    The differential cross section of the 40Ca(p,π+)41Ca reaction has been measured. The energy dependence of pion production near threshold has been studied at constant transferred momentum. The cross-section decreases by a factor 7, for proton energies varying from 154 to 149MeV (E(π) varies from 17.4 to 12.4MeV). The results are analyzed in the framework of the one nucleon mechanism

  16. Roots at the Percolation Threshold

    Science.gov (United States)

    Kroener, E.; Ahmed, M. A.; Kaestner, A.; Vontobel, P.; Zarebanadkouki, M.; Carminati, A.

    2014-12-01

    Much of the carbon assimilated by plants during photosynthesis is lost to the soil via rhizodepositions. One component of rhizopdeposition is mucilage, a hydrogel that dramatically alters the soil physical properties. Mucilage was assumed to explain unexpectedly low rhizosphere rewetting rates during irrigation (Carminati et al. 2010) and temporarily water repellency in the rhizosphere after severe drying (Moradi et al. 2012).Here, we present an experimental and theoretical study for the rewetting behaviour of a soil mixed with mucilage, which was used as an analogue of the rhizosphere. Our samples were made of two layers of untreated soils separated by a thin layer (ca. 1 mm) of soil treated with mucilage. We prepared soil columns of varying particle size, mucilage concentration and height of the middle layer above the water table. The dry soil columns were re-wetted by capillary rise from the bottom.The rewetting of the middle layer showed a distinct dual behavior. For mucilage concentrations lower than a certain threshold, water could cross the thin layer almost immediately after rewetting of bulk soil. At slightly higher mucilage concentrations, the thin layer was almost impermeable. The mucilage concentration at the threshold strongly depended on particle size: the smaller the particle size the larger the soil specific surface and the more mucilage was needed to cover the entire particle surface and to induce water repellency.We applied a classic pore network model to simulate the experimental observations. In the model a certain fraction of nodes were randomly disconnected to reproduce the effect of mucilage in temporarily blocking the flow. The percolation model could qualitatively reproduce well the threshold characteristics of the experiments. Our experiments, together with former observations of water dynamics in the rhizosphere, suggest that the rhizosphere is near the percolation threshold, where small variations in mucilage concentration sensitively

  17. Root finding with threshold circuits

    Czech Academy of Sciences Publication Activity Database

    Jeřábek, Emil

    2012-01-01

    Roč. 462, Nov 30 (2012), s. 59-69. ISSN 0304-3975 R&D Projects: GA AV ČR IAA100190902; GA MŠk(CZ) 1M0545 Institutional support: RVO:67985840 Keywords : root finding * threshold circuit * power series Subject RIV: BA - General Mathematics Impact factor: 0.489, year: 2012 http://www.sciencedirect.com/science/article/pii/S0304397512008006#

  18. Kauffman networks with threshold functions

    OpenAIRE

    Greil, Florian; Drossel, Barbara

    2007-01-01

    We investigate Threshold Random Boolean Networks with $K = 2$ inputs per node, which are equivalent to Kauffman networks, with only part of the canalyzing functions as update functions. According to the simplest consideration these networks should be critical but it turns out that they show a rich variety of behaviors, including periodic and chaotic oscillations. The results are supported by analytical calculations and computer simulations.

  19. JET and COMPASS asymmetrical disruptions

    Czech Academy of Sciences Publication Activity Database

    Gerasimov, S.N.; Abreu, P.; Baruzzo, M.; Drozdov, V.; Dvornova, A.; Havlíček, Josef; Hender, T.C.; Hronová-Bilyková, Olena; Kruezi, U.; Li, X.; Markovič, Tomáš; Pánek, Radomír; Rubinacci, G.; Tsalas, M.; Ventre, S.; Villone, F.; Zakharov, L.E.

    2015-01-01

    Roč. 55, č. 11 (2015), s. 113006-113006. ISSN 0029-5515 R&D Projects: GA MŠk(CZ) LM2011021 Institutional support: RVO:61389021 Keywords : tokamak * asymmetrical disruption * JET * COMPASS Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.062, year: 2014

  20. Disruptive Innovation in Healthcare & Rehabilitation

    DEFF Research Database (Denmark)

    Brooks, Anthony Lewis

    2014-01-01

    Disruption is a powerful body of theory that describes how people interact and react, how behavior is shaped, how organizational cultures form and influence decisions. Innovation is the process of translating an idea or invention into a product or service that creates value or for which customers...

  1. Supply disruption cost for power network planning

    International Nuclear Information System (INIS)

    A description is given of the method of approach to calculate the total annual socio-economic cost of power supply disruption and non-supplied energy, included the utilities' cost for planning. The total socio-economic supply disruption cost is the sum of the customers' disruption cost and the utilities' cost for failure and disruption. The mean weighted disruption cost for Norway for one hour disruption is NOK 19 per kWh. The customers' annual disruption cost is calculated with basis in the specific disruption cost referred to heavy load (January) and dimensioning maximum loads. The loads are reduced by factors taking into account the time variations of the failure frequency, duration, the loads and the disruption cost. 6 refs

  2. Combined injuries and their significance in catastrophic medicine

    International Nuclear Information System (INIS)

    The problems involved in combined injuries and their significance for catastrophe medicine are investigated in animal experiments. Rats and mice were irradiated under various conditions. In addition, they were subjected to further traumas such as wounds, application of chemotherapeuticals, stress, amongst others, in order to test these combined injuries. Certain pathological parameters such as the influence of these combined injuries on hematopoiesis, erythropoiesis, metabolic behaviour, histological investigations on organs, mortality, recovery phase were tested. It was thus shown that the dose and time dependence are of decisive importance. The effects of pure radiation injuries - compared to those injuries brought about by other parameters - generally do not give a summation of the injuries within the combined injuries. Rather, we find a very different effect picture of the combined injuries compared to the so-called 'single injuries'. The varying behaviour of the species is also remarkable so that one cannot directly relate these results to humans. The results clearly show that yet several animal species must be investigated in order to be able to draw conclusions regarding combined injuries in humans. (GSE)

  3. Evaluation of catastrophic failure risk in pressure vessels

    International Nuclear Information System (INIS)

    Within the Nordic countries a four-year research programme in the area of elastic-plastic fracture mechanics was initiated in 1985. Seven laboratories from Denmark, Finland, Norway and Sweden are participating in the programme. The main technical objective of the programme is to clarify how catastrophic fracture can be prevented in pressure vessels and piping by using the leak-before-break concept. The major experimental effort of the programme is destructive pressurization of a large size pressure vessel up to rupture. The vessel has dimensions similar to a nuclear reactor pressure vessel and it has been in operation for 20 years in a Finnish oil refinery plant. The materials characterization of the vessel has been partially carried out within an extensive Nordic round-robin programme. Two pressure tests have been carried out. In both tests an artificial sharp axial surface flaw was made on the inner wall of the vessel. The experimental details of the last test including repair welding of the vessel, flaw prepration, instrumentation and material characterization are described in this report. The fracture behaviour as well as experimental results are reported. The failure pressure is compared to estimates of the analytical pre-test calculations

  4. Role of senescence and mitotic catastrophe in cancer therapy

    Directory of Open Access Journals (Sweden)

    Shukla Yogeshwer

    2010-01-01

    Full Text Available Abstract Senescence and mitotic catastrophe (MC are two distinct crucial non-apoptotic mechanisms, often triggered in cancer cells and tissues in response to anti-cancer drugs. Chemotherapeuticals and myriad other factors induce cell eradication via these routes. While senescence drives the cells to a state of quiescence, MC drives the cells towards death during the course of mitosis. The senescent phenotype distinguishes tumor cells that survived drug exposure but lost the ability to form colonies from those that recover and proliferate after treatment. Although senescent cells do not proliferate, they are metabolically active and may secrete proteins with potential tumor-promoting activities. The other anti-proliferative response of tumor cells is MC that is a form of cell death that results from abnormal mitosis and leads to the formation of interphase cells with multiple micronuclei. Different classes of cytotoxic agents induce MC, but the pathways of abnormal mitosis differ depending on the nature of the inducer and the status of cell-cycle checkpoints. In this review, we compare the two pathways and mention that they are activated to curb the growth of tumors. Altogether, we have highlighted the possibilities of the use of senescence targeting drugs, mitotic kinases and anti-mitotic agents in fabricating novel strategies in cancer control.

  5. Chandler wobble excitation by catastrophic flooding of the Black Sea

    Directory of Open Access Journals (Sweden)

    E. Boschi

    1999-06-01

    Full Text Available It is now widely accepted that during the late Quaternary glaciation the Black Sea formed an isolated inland lake (Ross et al., 1970. New geological data and the recognition of sudden population movements away from the Black Sea coasts suggest that the basin was rapidly flooded through the Bosphorus sill 7150 years bp, causing a sea level rise of ~ 135 m in a few years (Ryan et al., 1997. As shown here, such a catastrophic redistribution of mass has significantly altered the amplitude of the Chandler wobble, the free motion of the pole of rotation around the main inertia axis of the Earth (Lambeck, 1980. We also estimate that during the flooding the pole of rotation was diverted from its secular path and shifted by ~ 30 m, at a rate of several meters per year. These rotational variations are found to be orders of magnitude larger than those produced by other short-term geophysical processes, such as earthquakes seismic moment release (O'Connell and Dziewonski, 1979; Chao et al.,1996, anthropogenic water impoundment (Chao, 1995, and tectonic mass movements (Alfonsi and Spada, 1998. The Black Sea flooding may thus be responsible for the most drastic change in the rotational parameters of the Earth in the recent history of our planet.

  6. Vital signs: a banner year, barring political and economic catastrophes

    International Nuclear Information System (INIS)

    Barring political and economic catastrophes, key indicators in the oil and gas industry point to a good year in 2003. The optimistic forecast is based on strong commodity prices through the first quarter despite the anticipated military action in Iraq, strong land sale activity, capacity employment of drilling fleets and seriously depleted natural gas storage caverns across North America. In terms of well completions, Canada is looking for 17,500 completions in 2003, an 11 per cent increase over 2002. Crude markets are expected to be slightly weaker, but prices are expected to remain in the $27 to $29 range for many months to come, owing to the tight inventory situation throughout the western world. Similar fundamentals were responsible for strong performance by Canadian energy exporters in 2002, as shown by a number of statistical tables that form part of this article. Electricity prices are also expected to remain higher than in 2002, given that natural gas prices are high and snow packs lower than last year. FirstEnergy Capital Corporation pegged the Alberta power price to average $64.46 per megawatt-hour this year, up from $55.77 per megawatt-hour last year. tabs

  7. Quantifying the hurricane catastrophe risk to offshore wind power.

    Science.gov (United States)

    Rose, Stephen; Jaramillo, Paulina; Small, Mitchell J; Apt, Jay

    2013-12-01

    The U.S. Department of Energy has estimated that over 50 GW of offshore wind power will be required for the United States to generate 20% of its electricity from wind. Developers are actively planning offshore wind farms along the U.S. Atlantic and Gulf coasts and several leases have been signed for offshore sites. These planned projects are in areas that are sometimes struck by hurricanes. We present a method to estimate the catastrophe risk to offshore wind power using simulated hurricanes. Using this method, we estimate the fraction of offshore wind power simultaneously offline and the cumulative damage in a region. In Texas, the most vulnerable region we studied, 10% of offshore wind power could be offline simultaneously because of hurricane damage with a 100-year return period and 6% could be destroyed in any 10-year period. We also estimate the risks to single wind farms in four representative locations; we find the risks are significant but lower than those estimated in previously published results. Much of the hurricane risk to offshore wind turbines can be mitigated by designing turbines for higher maximum wind speeds, ensuring that turbine nacelles can turn quickly to track the wind direction even when grid power is lost, and building in areas with lower risk. PMID:23763387

  8. Catastrophic debris avalanche deposit of Socompa volcano, northern Chile

    Science.gov (United States)

    Francis, P. W.; Gardeweg, M.; Ramirez, C. F.; Rothery, D. A.

    1985-01-01

    Between 10,000 and 500 yr ago the Socompa volcano in northern Chile experienced a catastrophic collapse of a 70 deg sector of the original cone, causing a debris avalanche that descended nearly 3000 m vertically and traveled more than 35 km from the volcano. The deposits cover some 490 sq km and have a minimum volume of 15 cu km. Parts of the original cone slumped in a nearly coherent form and are now preserved as large blocks more than 400 m high. The primary avalanche traveled northwestward over sloping ground before coming to rest transiently, forming a prominent marginal ridge, and then slid away northeastward to form a secondary flow, overriding much of the primary avalanche deposit. Abundant, prismatic, jointed dacite blocks within the debris avalanche deposit and a thin, fine-grained pumiceous deposit beneath it suggest that the collapse was triggered by magmatic activity and may have been accompanied by a violent lateral blast. Collapse was followed by eruption of pumiceous pyroclastic flows and extrusion of voluminous dacite domes.

  9. Reconciling the infrared catastrophe and observations of SN 2011fe

    CERN Document Server

    Fransson, Claes

    2015-01-01

    The observational effects of the 'Infrared Catastrophe' are discussed in view of the very late observations of the Type Ia SN 2011fe. Our model spectra at 1000d take non-local radiative transfer into account, and find that this has a crucial impact on the spectral formation. Although rapid cooling of the ejecta to a few 100 K occurs also in these models, the late-time optical/NIR flux is brighter by 1-2 magnitudes due to redistribution of UV emissivity, resulting from non-thermal excitation and ionization. This effect brings models into better agreement with late-time observations of SN 2011fe and other Type Ia supernovae, and offers a solution to the long standing discrepancy between models and observations. The models show that spectral formation shifts from Fe II and Fe III at 300d to Fe I at 1000d, which explains the apparent wavelength shifts seen in SN2011fe. We discuss effects of time dependence and energy input from 57Co, finding both to be important at 1000d.

  10. Quantum resonance catastrophe for conductance through a periodically driven barrier

    Science.gov (United States)

    Thuberg, Daniel; Reyes, Sebastián A.; Eggert, Sebastian

    2016-05-01

    We consider the quantum conductance in a tight-binding chain with a locally applied potential which is oscillating in time. The steady state for such a driven impurity can be calculated exactly for any energy and applied potential using the Floquet formalism. The resulting transmission has a nontrivial, nonmonotonic behavior depending on incoming momentum, driving frequency, and the strength of the applied periodic potential. Hence there is an abundance of tuning possibilities, which allows finding the resonances of total reflection for any choice of incoming momentum and periodic potential. Remarkably, this implies that even for an arbitrarily small infinitesimal impurity potential it is always possible to find a resonance frequency at which there is a catastrophic breakdown of the transmission T =0 . The points of zero transmission are closely related to the phenomenon of Fano resonances at dynamically created bound states in the continuum. The results are relevant for a variety of one-dimensional systems where local AC driving is possible, such as quantum nanodot arrays, ultracold gases in optical lattices, photonic crystals, or molecular electronics.

  11. Catastrophic anoxia in the chesapeake bay in 1984.

    Science.gov (United States)

    Seliger, H H; Boggs, J A; Biggley, W H

    1985-04-01

    In 1984, four climatic sequences combined to produce what may be a major anoxic catastrophe in the northern Chesapeake Bay, sufficient to severely threaten the major benthic species. These sequences are (i) the highest late-winter streamflow on record from the Susquehanna River watershed; (ii) streamflows from the Susquehanna River for the consecutive months of June, July, and August that are higher by 2 standard deviations than the respective monthly mean values measured over the last 34 years; (iii) a stationary high in August off the Atlantic Coast; and (iv) an absence of strong storm events in summer. An empirical equation is proposed for the prediction of the monthly trend of dissolved oxygen decrease in terms of a temperature-dependent subpycnoclinal respiration and a modified estuarine Richardson number. As of 23 August 1984, the summer pycnocline of the northern bay had eroded upward from its historically recorded depth below 10 meters to an abnormally shallow 5 meters, with higher stratification than in earlier years. Dissolved oxygen concentrations directly below the pycnocline decreased to zero during June, 2 months earlier than for previous wet years. At present, oxygen-deficient waters containing significant concentrations of hydrogen sulfide have penetrated into Eastern Bay and the Choptank and Potomac rivers. Because most remaining shellfish-spawning and seed-bed areas in these tributaries are located at depths between 4 and 8 meters, the continued absence of major destratifying events will prolong the present anoxic trend and may result in high benthic mortalities. PMID:17811570

  12. Radiation-induced mitotic catastrophe in PARG-deficient cells

    International Nuclear Information System (INIS)

    Poly(ADP-ribosyl)ation is a post-translational modification of proteins involved in the regulation of chromatin structure, DNA metabolism, cell division and cell death. Through the hydrolysis of poly(ADP-ribose) (PAR), Poly(ADP-ribose) glyco-hydrolase (PARG) has a crucial role in the control of life-and-death balance following DNA insult. Comprehension of PARG function has been hindered by the existence of many PARG isoforms encoded by a single gene and displaying various subcellular localizations. To gain insight into the function of PARG in response to irradiation, we constitutively and stably knocked down expression of PARG isoforms in HeLa cells. PARG depletion leading to PAR accumulation was not deleterious to undamaged cells and was in fact rather beneficial, because it protected cells from spontaneous single-strand breaks and telomeric abnormalities. By contrast, PARG-deficient cells showed increased radiosensitivity, caused by defects in the repair of single- and double-strand breaks and in mitotic spindle checkpoint, leading to alteration of progression of mitosis. Irradiated PARG-deficient cells displayed centrosome amplification leading to mitotic supernumerary spindle poles, and accumulated aberrant mitotic figures, which induced either polyploidy or cell death by mitotic catastrophe. Our results suggest that PARG could be a novel potential therapeutic target for radiotherapy. (authors)

  13. Can non-ideal magnetohydrodynamics solve the magnetic braking catastrophe?

    Science.gov (United States)

    Wurster, James; Price, Daniel J.; Bate, Matthew R.

    2016-03-01

    We investigate whether or not the low ionization fractions in molecular cloud cores can solve the `magnetic braking catastrophe', where magnetic fields prevent the formation of circumstellar discs around young stars. We perform three-dimensional smoothed particle non-ideal magnetohydrodynamics (MHD) simulations of the gravitational collapse of one solar mass molecular cloud cores, incorporating the effects of ambipolar diffusion, Ohmic resistivity and the Hall effect alongside a self-consistent calculation of the ionization chemistry assuming 0.1 μm grains. When including only ambipolar diffusion or Ohmic resistivity, discs do not form in the presence of strong magnetic fields, similar to the cases using ideal MHD. With the Hall effect included, disc formation depends on the direction of the magnetic field with respect to the rotation vector of the gas cloud. When the vectors are aligned, strong magnetic braking occurs and no disc is formed. When the vectors are anti-aligned, a disc with radius of 13 au can form even in strong magnetic when all three non-ideal terms are present, and a disc of 38 au can form when only the Hall effect is present; in both cases, a counter-rotating envelope forms around the first hydrostatic core. For weaker, anti-aligned fields, the Hall effect produces massive discs comparable to those produced in the absence of magnetic fields, suggesting that planet formation via gravitational instability may depend on the sign of the magnetic field in the precursor molecular cloud core.

  14. Lorentz violating kinematics: threshold theorems

    Science.gov (United States)

    Baccetti, Valentina; Tate, Kyle; Visser, Matt

    2012-03-01

    Recent tentative experimental indications, and the subsequent theoretical speculations, regarding possible violations of Lorentz invariance have attracted a vast amount of attention. An important technical issue that considerably complicates detailed calculations in any such scenario, is that once one violates Lorentz invariance the analysis of thresholds in both scattering and decay processes becomes extremely subtle, with many new and naively unexpected effects. In the current article we develop several extremely general threshold theorems that depend only on the existence of some energy momentum relation E(p), eschewing even assumptions of isotropy or monotonicity. We shall argue that there are physically interesting situations where such a level of generality is called for, and that existing (partial) results in the literature make unnecessary technical assumptions. Even in this most general of settings, we show that at threshold all final state particles move with the same 3-velocity, while initial state particles must have 3-velocities parallel/anti-parallel to the final state particles. In contrast the various 3-momenta can behave in a complicatedand counter-intuitive manner.

  15. Catastrophe versus instability for the eruption of a toroidal solar magnetic flux rope

    CERN Document Server

    Kliem, B; Forbes, T G; Priest, E R; Török, T

    2014-01-01

    The onset of a solar eruption is formulated here as either a magnetic catastrophe or as an instability. Both start with the same equation of force balance governing the underlying equilibria. Using a toroidal flux rope in an external bipolar or quadrupolar field as a model for the current-carrying flux, we demonstrate the occurrence of a fold catastrophe by loss of equilibrium for several representative evolutionary sequences in the stable domain of parameter space. We verify that this catastrophe and the torus instability occur at the same point; they are thus equivalent descriptions for the onset condition of solar eruptions.

  16. Catastrophe versus instability for the eruption of a toroidal solar magnetic flux rope

    Energy Technology Data Exchange (ETDEWEB)

    Kliem, B.; Lin, J. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Forbes, T. G. [Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, New Hampshire 03824 (United States); Priest, E. R. [School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews KY16 9SS (United Kingdom); Török, T., E-mail: bkliem@uni-potdam.de [Predictive Science Inc., 9990 Mesa Rim Rd., Ste 170, San Diego, CA 92121 (United States)

    2014-07-01

    The onset of a solar eruption is formulated here as either a magnetic catastrophe or as an instability. Both start with the same equation of force balance governing the underlying equilibria. Using a toroidal flux rope in an external bipolar or quadrupolar field as a model for the current-carrying flux, we demonstrate the occurrence of a fold catastrophe by loss of equilibrium for several representative evolutionary sequences in the stable domain of parameter space. We verify that this catastrophe and the torus instability occur at the same point; they are thus equivalent descriptions for the onset condition of solar eruptions.

  17. Vers une ontologie des risques et des catastrophes : le modèle conceptuel

    OpenAIRE

    Provitolo, Damienne; Dubos-Paillard, Edwige; Müller, Jean-Pierre

    2009-01-01

    Nous présentons une réflexion sur la construction d'une ontologie formalisée du domaine des risques et des catastrophes. L'objectif est de revenir sur les concepts essentiels permettant de caractériser le risque, l'accident, la catastrophe et les notions associées, et d'organiser ces concepts entre eux par des relations. Nous présentons donc le modèle conceptuel du domaine des risques et des catastrophes, modèle réalisé à partir des diagrammes de classe d'UML(Unified Modelling Language). Si l...

  18. Catastrophe versus instability for the eruption of a toroidal solar magnetic flux rope

    International Nuclear Information System (INIS)

    The onset of a solar eruption is formulated here as either a magnetic catastrophe or as an instability. Both start with the same equation of force balance governing the underlying equilibria. Using a toroidal flux rope in an external bipolar or quadrupolar field as a model for the current-carrying flux, we demonstrate the occurrence of a fold catastrophe by loss of equilibrium for several representative evolutionary sequences in the stable domain of parameter space. We verify that this catastrophe and the torus instability occur at the same point; they are thus equivalent descriptions for the onset condition of solar eruptions.

  19. Voting on Thresholds for Public Goods

    DEFF Research Database (Denmark)

    Rauchdobler, Julian; Sausgruber, Rupert; Tyran, Jean-Robert

    Introducing a threshold in the sense of a minimal project size transforms a public goods game with an inefficient equilibrium into a coordination game with a set of Pareto-superior equilibria. Thresholds may therefore improve efficiency in the voluntary provision of public goods. In our one......-shot experiment, we find that coordination often fails and exogenously imposed thresholds are ineffective at best and often counter-productive. This holds under a range of threshold levels and refund rates. We test if thresholds perform better if they are endogenously chosen, i.e. if a threshold is approved in a...

  20. 30 years life with Chernobyl, 5 years life with Fukushima. Health consequences of the nuclear catastrophes of Chernobyl and Fukushima

    International Nuclear Information System (INIS)

    The IPPNW report on health consequences of the nuclear catastrophes of Chernobyl and Fukushima covers the following issues: Part.: 30 years life with Chernobyl: Summarized consequences of Chernobyl, the accident progression, basic data of the catastrophe, estimation of health hazards as a consequence of the severe accident of Chernobyl, health consequences for the liquidators, health consequences for the contaminated population, mutagenic and teratogenic effects. Part B: 5 years life with Fukushima: The start of the nuclear catastrophe, emissions and contamination, consequences of the nuclear catastrophe on human health, thyroid surveys in the prefecture Fukushima, consequences of the nuclear catastrophe on the ecosystem, outlook.

  1. Variable Threshold MOSFET Approach (Through Dynamic Threshold MOSFET) For Universal Logic Gates

    OpenAIRE

    Ragini, K.; DR.M. SATYAM; Dr. B.C. Jinaga

    2010-01-01

    In this article, we proposed a Variable threshold MOSFET(VTMOS)approach which is realized from Dynamic Threshold MOSFET(DTMOS), suitable for sub-threshold digital circuit operation. Basically the principle of sub- threshold logics is operating MOSFET in sub-threshold region and using the leakage current in that region for switching action, there by drastically decreasing power. To reduce the power consumption of sub-threshold circuits further, a novel body biasing technique termed VTMOS is in...

  2. Establishment and Application of Assessment Indicator System of Agricultural Catastrophe Vulnerability

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    To give play to the role of agricultural catastrophe risk fund in spreading agricultural catastrophe risk,we select natural conditions,economic conditions,social conditions,as the external vulnerability assessment indicators;select commodity rate of agricultural products,substitutability of agricultural products,the extent of agricultural products being related to the national economy and the people’s livelihood,as the internal vulnerability assessment indicators.We assign weight to indicators using Analytic Hierarchy Process,and establish assessment indicator system of agricultural catastrophe vulnerability,to analyze the compensation for losses of different agricultural products arising from agricultural catastrophe in different regions.And we take the case of rice in Sichuan Province,to demonstrate the role this indicator system.

  3. Global Catastrophes in Earth History: An Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality

    Science.gov (United States)

    1988-01-01

    Topics addressed include: Cretaceous-Tertiary mass extinctions; geologial indicators for meteorite collisions; carbon dioxide catastrophes; volcanism; climatic changes; geochemistry; mineralogy; fossil records; biospheric traumas; stratigraphy; mathematical models; and ocean dynamics.

  4. Mindfulness, functioning and catastrophizing after multidisciplinary pain management for chronic low back pain.

    Science.gov (United States)

    Cassidy, Emma Louise; Atherton, Rachel Jane; Robertson, Noelle; Walsh, David Andrew; Gillett, Raphael

    2012-03-01

    We examined mindfulness in people with chronic low back pain who were attending a multidisciplinary pain management programme. Participants completed questionnaires at baseline (n=116) and after a 3-month cognitive-behaviourally informed multidisciplinary intervention (n=87). Self-reported mindfulness was measured before and after the intervention, and relationships were explored between mindfulness, disability, affect and pain catastrophizing. Mindfulness increased following participation in the intervention, and greater mindfulness was predictive of lower levels of disability, anxiety, depression and catastrophizing, even when pain severity was controlled. Mediator analyses suggested that the relationship between mindfulness and disability was mediated by catastrophizing. It is possible that cognitive-behavioural interventions and processes can affect both catastrophizing and mindfulness. PMID:22240149

  5. Catastrophe plan for areas surrounding nuclear facilities in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    In the FRG, the federal government is responsible for the construction and operation of nuclear facilities, as well as defence measures against the 'damaging effect of ionizing radiation'. The responsibility of guarding public safety and order from danger lies with the states. Catastrophe defense is a special part in this scope of duties. It guards against such interferences in public safety and order which, because of their extraordinary consequences and the necessity of specially organized defense, we call catastrophes. The duty of catastrophe defence is to prevent or alleviate immediate consequences for the population from high amounts of released radioactivity. This means that the catastrophe defence is equipped to prevent or aleviate so called non-stochastic damages, especially early damages, and to reduce individual risk

  6. Transient probabilities for a simple birth-death-immigration process under the influence of total catastrophes

    Directory of Open Access Journals (Sweden)

    Randall J. Swift

    2001-03-01

    Full Text Available The transient probabilities for a simple birth-death-immigration process are considered. Catastrophes occur at a constant rate, and when they occur, reduce the population to size zero.

  7. Extravasational side effects of cytotoxic drugs: A preventable catastrophe

    Directory of Open Access Journals (Sweden)

    Thakur Jagdeep

    2008-01-01

    Full Text Available In addition to their therapeutic effects on malignant cells, cytotoxic agents have the potential of causing destruction of healthy, normal cells. Extravasation of the drug can produce extensive necrosis of the skin and subcutaneous tissue. Management of these extravasational effects differs from one centre to another and prevention is usually strongly emphasized. We analyzed our management of 12 patients referred to us over five years with extravasation of cytotoxic drugs and reviewed the literature for different approaches with regard to prophylaxis and management of extravasational effects. Materials and Methods: This study was done in the department of plastic surgery of a medical college. Five years of retrospective data were studied of patients referred to our department with extravasation of cytotoxic drugs. Results: We managed 12 cases referred to our department with extravasation of cytotoxic drugs. Mitomycin C was used in seven cases (58.33%, vincristine in two cases (16.66%, 5-Florouracil in another two cases while doxorubicin was responsible for extravasational side effects in one case (8.33%. The size of necrosis ranged from 3.75 cm 2 to 25 cm 2 with average size of 9.6 cm 2 . In terms of the area involved, the dorsum of the hand was involved in five cases (41.66%, the wrist in another five cases (41.66%, and the cubital fossa in the remaining two cases (16.66%. All cases were treated with daily debridement of necrotic tissue, saline dressing, and split skin grafting. Conclusion: Extravasation of cytotoxic drugs further increases the suffering of cancer patients. This catastrophe can only be avoided by vigilance and immediate application of antidotes. Once the local toxicity of the drugs takes effect, morbidity is unavoidable

  8. Fully-coupled hydrometeorological prediction of catastrophic Mediterranean floods

    Science.gov (United States)

    Rebora, N.; Gabellani, S.; Rudari, R.; Silvestro, F.; Parodi, A.; Gochis, D.

    2012-12-01

    On November 4th, 2011, the city of Genoa, Italy, located between the Tyrrhenian Sea and the Apennine mountains, was witness to a catastrophic flash flood. About 500 millimeters of rain -a third of the average annual rainfall- fell in approximately six hours. The waters that flooded the town center equated to an approximately 300 year flood event. Six people perished, commercial property was inundated, cars were swept away and many trees were uprooted. We analyze the performance of cloud-permitting (1 km) model simulations of the convective system responsible for this extreme event using the Advanced Research Weather and Forecasting Model (ARW-WRF, version 3.3) with its associated hydrological modeling extension ('WRF-Hydro') focusing on the utility of model quantitative precipitation forecasts (QPFs) for flash flood prediction. WRF model skill is assessed with respect to specification of cloud microphysics, convection and land surface physics parameterizations. The QPF results strongly suggest an event dominated by comparatively shallow warm rain processes where local maxima were the product of both synoptic scale dynamics and orographic enhancement over the Apennine mountain range. Land and sea surface temperature forcing was assess but found to be secondary in importance. Streamflow prediction skill from the fully coupled WRF-Hydro modeling system was compared against observations and against offline or 'uncoupled' hydrological model runs, driven by several quantitative precipitation estimate (QPEs) products. The results illustrate the significant sensitivity of the predicted (simulated) streamflow event to QPF (QPE) skill and emphasize the importance of taking into account many factors and sources of error in the hydrometeorological prediction chain. The end product of this study is a comprehensive evaluation and justification for optimal configurations of the WRF-Hydro modeling system for high-impact Mediterranean flood events for use in future forecasting

  9. Terrestrial evidence of a nuclear catastrophe in paleoindian times

    International Nuclear Information System (INIS)

    A common problem at paleoindian sites in the northeastern region of North America is the recovery of radiocarbon dates that are much younger than their western counterparts, sometimes by as much as 10,000 years. Other methods like thermoluminescence, geoarchaeology, and sedimentation suggest that the dates are incorrect. Evidence has been mounting that the peopling of the Americas occurred much earlier than 12,000 bp. The discovery of tracks and micrometeorite-like particles in paleoindian artifacts across North America demonstrates they were bombarded during a cosmic event. Measurements of Uranium 235 (235U), depleted by 17-77%, and enhanced concentrations of Plutonium 239 (239Pu), from neutron capture on Uranium 238 (238U), in artifacts, associated chert types, and sediments at depth indicates that the entire prehistoric North American landscape was bombarded by thermal neutrons. Radiocarbon dating assumes that there is no substantial change in isotopic composition over time. A large thermal neutron event would convert residual Nitrogen 14 (14N) in charcoal to Carbon 14 (14C) thus resetting the radiocarbon date to a younger value and pushing back the date that paleoindians occupied the Americas by thousands of years. Analysis of data from 11 locations across North America indicates there were episodes of cosmic ray bombardments of the prehistoric landscape in Late Glacial times. Examination of the radiocarbon record suggests these events were coupled with geomagnetic excursions at 41,000, 33,000, and 12,500 bp and irradiated the landscape with massive thermal neutron fluxes of the order of approximately1015 neutrons/cm2. These data provide a clear body of terrestrial evidence supporting either one of two longstanding hypotheses for catastrophe in paleoindian times: (1) a giant solar flare during a geomagnetic excursion as explored by Wolfendale and Zook, and (2) a supernova shockwave as forwarded by Brackenridge, Clarke, and Dar. The evidence is reviewed, and

  10. Using Catastrophe-Linked Securities to Diversity Insurance Risk: A Financial Analysis of Cat Bonds

    OpenAIRE

    Henri Louberge; Evis Kellezi; Manfred Gilli

    1999-01-01

    Severe natural catastrophes in the early 1990s generated a lack of financial capacity in the catastrophe line of the global reinsurance market. The finance industry reacted to this situation by issuing innovative products designed to spread the excess risk more widely among international investors (risk securitization). The paper reviews these developments and emphasizes their significance with respect to the economic theory of risk exchanges. Special attention is devoted to the case of catas...

  11. Use of catastrophe risk models in assessing sovereign food security for risk transfer

    OpenAIRE

    Sharma, Mohan; Hohl, Roman

    2015-01-01

    This paper discusses how catastrophe crop risk models can be used to assess food security needs at the sovereign level for the purpose of risk transfer. The rationale for a system to evaluate food security needs at the national level is discussed. The role of technology and remote sensing data availability as an enabler of catastrophe crop risk models is discussed followed by a description...

  12. Financial Innovation in Property Catastrophe Reinsurance: The Convergence of Insurance and Capital Markets

    OpenAIRE

    Chichilnisky, Graciela

    1996-01-01

    The property catastrophe reinsurance industry faces a major challenge. Since 1989, climatic volatility has produced unprecedented insured losses of $43 billion, $18 billion of which were from Hurricane Andrew alone. A surge of insurer defaults and dramatic changes in capacity and pricing have followed in their wake. Catastrophic risks must be addressed with innovative financial approaches that bring the insurance industry closer to the securities industry. This article discusses the new f...

  13. Equilibrium balking strategies in the single server Markovian queue with catastrophes

    CERN Document Server

    Boudali, Olga

    2011-01-01

    We consider a Markovian queue subject to Poisson generated catastrophes. Whenever a catastrophe occurs, all customers are forced to abandon the system, the server is rendered inoperative and an exponential repair time is set on. We assume that the arriving customers decide whether to join the system or balk, based on a natural reward-cost structure. We study the balking behavior of the customers and derive the corresponding Nash equilibrium strategies.

  14. Collaboration or Control?: the struggle for power in catastrophic disaster response

    OpenAIRE

    Lombardo, Tony S.

    2007-01-01

    Past domestic catastrophic disasters have required massive Department of Defense (DoD) Title 10 involvement. During Hurricanes Andrew and Katrina, DoDs initial response, although critical, was criticized as slow. The increased risks to the United States of cataclysmic events have solidified DoDs mandatory response to future events. This has punctuated the importance of DoDs initial response capability. Historically, DoDs response to catastrophic disasters was instantaneous. This was in p...

  15. Cross-cultural adaptation, reliability, and validity of the German version of the Pain Catastrophizing Scale

    OpenAIRE

    Meyer, K.; Sprott, H.; Mannion, A. F.

    2008-01-01

    OBJECTIVE: In patients with chronic pain, catastrophizing is a significant determinant of self-rated pain intensity and disability. The Pain Catastrophizing Scale (PCS) was developed to assist with both treatment planning and outcome assessment; to date, no German version has been validated. METHODS: A cross-cultural adaptation of the PCS into German was carried out, strictly according to recommended methods. A questionnaire booklet containing the PCS, visual analogue scales (numeric rating s...

  16. The importance of catastrophizing for successful pharmacological treatment of peripheral neuropathic pain

    Directory of Open Access Journals (Sweden)

    Toth C

    2014-06-01

    Full Text Available Cory Toth, Shauna Brady, Melinda Hatfield Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada Objective: Catastrophizing may be a negative predictor of pain-related outcomes. We evaluated the impact of catastrophizing upon success of first-line pharmacotherapy in the management of neuropathic pain (NeP due to peripheral polyneuropathy. Methods: Patients with confirmed NeP with NeP Visual Analog Scale (VAS pain severity score ≥4 (0–10 scale completed the Coping Strategies Questionnaire (CSQ catastrophizing subscale at baseline. Pharmacological therapy consisting of first-line agents gabapentin, pregabalin, or a tricyclic antidepressant was initiated. Other measures examined included the Karnofsky Performance Scale, Beck Depression Inventory, EuroQol Quality of Life Health Questionnaire, and Modified Brief Pain Inventory. At 3 and 6 months, questionnaires were repeated and adverse effect reporting was completed. Outcome measures assessed were pharmacotherapy success (≥30% relief of NeP and tolerability over 6 months of follow-up. Bivariate relationships using Pearson product-moment correlations were examined for baseline CSQ catastrophizing subscale score and the change in the NeP VAS scores and medication discontinuation. Results: Sixty-six patients were screened, 62 subjects participated, and 58 subjects (94% completed the final follow-up visit. Greater catastrophizing was associated with poor pain relief response and greater likelihood of discontinuation of pharmacotherapy, reports of greater disability, and impaired quality of life. Duration of pain was negatively associated with likelihood of pharmacotherapy success. Conclusion: Catastrophizing exerts maladaptive effects on outcomes with pharmacotherapy in NeP patients. Detection of catastrophizing during clinical visits when pharmacological therapy is being considered can be a predictive factor for patient outcomes. Keywords: neuropathic pain

  17. Catastrophizing and fear of tinnitus predict quality of life in patients with chronic tinnitus

    OpenAIRE

    Cima, Rilana FF; Crombez, Geert; Vlaeyen, Johan WS

    2011-01-01

    Objectives: It is well established that catastrophic misinterpretations and fear are involved in the suffering and disability of patients with chronic pain. This study investigated whether similar processes explain suffering and disability in patients with chronic tinnitus. We hypothesized that patients who catastrophically (mis)interpret their tinnitus would be more fearful of tinnitus, more vigilant toward their tinnitus, and report less quality of life. Moreover, tinnitus-related fear was ...

  18. Validity and Reliability of the Catastrophic Cognitions Questionnaire-Turkish Version

    OpenAIRE

    Ayse Kart

    2016-01-01

    Aim: Importance of catastrophic cognitions is well known for the development and maintance of panic disorder. Catastrophic Cognitions Questionnaire (CCQ) measures thoughts associated with danger and was originally developed by Khawaja (1992). In this study, it is aimed to evaluate the validity and reliability of CCQ- Turkish version. Material and Method: CCQ was administered to 250 patients with panic disorder. Turkish version of CCQ was created by translation, back-translation and pilot as...

  19. Household catastrophic health expenditure: evidence from Georgia and its policy implications

    Directory of Open Access Journals (Sweden)

    Zoidze Akaki

    2009-04-01

    Full Text Available Abstract Background To quantify extent of catastrophic household health expenditures, determine factors influencing it and estimate Fairness in Financial Contribution (FFC index in Georgia to establish the baseline for expected reforms and contribute to the design and fine-tuning of the major reforms in health care financing initiated by the government mid-2007. Methods The research is based on the nationally representative Health Care Utilization and Expenditure survey conducted during May-June 2007, prior to preparing for new phase of implementation for the health care financing reforms. Households' catastrophic health expenditures were estimated according to the methodology proposed by WHO – Ke Xu 1. A logistic regression (logit model was used to predict probability of catastrophic health expenditure occurrence. Results In Georgia between 2000 and 2007 access to care for poor has improved slightly and the share of households facing catastrophic health expenditures have seemingly increased from 2.8% in 1999 to 11.7% in 2007. However, this variance may be associated with the methodological differences of the respective surveys from which the analysis were derived. The high level of the catastrophic health expenditure may be associated with the low share of prepayment in national health expenditure, adequate availability of services and a high level of poverty in the country. Major factors determining the financial catastrophe related to ill health were hospitalization, household members with chronic illness and poverty status of the household. The FFC for Georgia appears to have improved since 2004. Conclusion Reducing the prevalence of catastrophic health expenditure is a policy objective of the government, which can be achieved by focusing on increased financial protection offered to poor and expanding government financed benefits for poor and chronically ill by including and expanding inpatient coverage and adding drug benefits. This

  20. Childhood Trauma and Pain and Pain Catastrophizing in Adulthood: A Cross-Sectional Survey Study

    OpenAIRE

    Sansone, Randy A.; Watts, Daron A.; Wiederman, Michael W.

    2013-01-01

    Objective: Previous studies have indicated relationships between trauma in childhood and pain in adulthood, although some studies have reported no such relationships and challenge the methodologies of large-scale community samples. In this study involving a clinical sample, we examined relationships among (1) childhood trauma at ages 12 or younger, (2) rated pain for 3 time points in adulthood, and (3) pain catastrophizing (ie, catastrophic thoughts and feelings about pain).

  1. A CATASTROPHIC-CUM-RESTORATIVE QUEUING SYSTEM WITH CORRELATED BATCH ARRIVALS AND VARIABLE CAPACITY

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar

    2008-07-01

    Full Text Available In this paper, we study a catastrophic-cum-restorative queuing system with correlated batch arrivals and service in batches of variable sizes. We perform the transient analysis of the queuing model. We obtain the Laplace Transform of the probability generating function of system size. Finally, some particular cases of the model have been derived and discussed. Keywords: Queue length, Catastrophes, Correlated batch arrivals, Broadband services, Variable service capacity, and Restoration.

  2. Using of catastrophe theory for processing of experimental results measured in low-temperature plasma

    International Nuclear Information System (INIS)

    For acoustoplasma of CO2 laser the obtained family of dynamic volt-ampere characteristics for different modulation frequencies of the discharge current is described by catastrophe theory. We propose a method of processing the experimental results, which allows obtaining not only qualitative but also quantitative characteristics of the control parameters. The best agreement with experimental data is obtained for 'dovetail catastrophe'. The areas of changing of control parameters are determined

  3. Cusp catastrophe of symmetry breaking in two-component Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Bifurcation analysis is applied to the spontaneous spatial symmetry breaking occurring in the ground state of two-component Bose-Einstein condensates. The cusp catastrophe describing the supercritical pitchfork bifurcation associated with the symmetry breaking is derived via the identification of the local curvature of the Gross-Pitaevskii energy functional. The bifurcation diagram and universal scaling laws for the eigenvalue and energy are obtained from the catastrophe function

  4. PMI Thresholds for GDP Growth

    OpenAIRE

    Kilinc, Zubeyir; Yucel, Eray

    2016-01-01

    In this study, we try to uncover the information capacity of the Purchasing Managers Index (PMI) as a leading indicator of GDP growth of euro area. Our results show that PMI carries a significant amount of information that can be used to forecast the growth rate in the current as well as subsequent quarters. In particular, having verified that a PMI level around 50 works as the threshold distinguishing between positive and negative rates of GDP growth, we establish a sequence of other PMI thr...

  5. Oscillation threshold of woodwind instruments

    OpenAIRE

    Grand, Noël; Gilbert, Joël; Laloë, Franck

    1997-01-01

    this version has figures at the end, which was not the case of version 1 We give a theoretical study of the nature of the bifurcations occurring at the oscillation threshold of woodwind instruments, or of physical systems obeying similar non-linear equations of motion. We start from the simplest description of the acoustical behavior these instruments, a mathematical model containing two equations only, one of which is linear but includes delays, while the other is non-linear but has no de...

  6. An analysis and reduction of disruptive behavior on school buses.

    Science.gov (United States)

    Greene, B F; Bailey, J S; Barber, F

    1981-01-01

    Thousands of children are injured or killed each year in school bus accidents. A significant number of these tragic incidents is precipitated by disruptive child behavior that distracts the drivers from their difficult task. Two experiments were conducted which addressed this problem. For both experiments an automated sound recording device (referred to as a Noise Guard) selectively responsive to frequencies above 500 Hz (i.e., unresponsive to bus drone) recorded both the duration and frequency of noise outbursts above a tolerable threshold. Additionally, an observer made in situ measurements of other disruptions including roughhousing and getting-out-of-seat. In the first experiment, following baseline measurements of these behaviors, middle-school students received feedback for noise outbursts. That is, when "Noise Guard" was activated, it in turn operated one of several lights on a panel visible to all passengers. Each day students were allowed to listen to high-appeal taped music while riding the bus and to participate in a raffle for prizes, provided the number of outbursts on the preceding day remained below a specified criterion indicated on the light panel. This intervention resulted in drastic reductions of noise outbursts with a concomitant reduction in other disruptive behaviors. Comparable results were obtained in the second experiment which eliminated the raffle from the intervention. PMID:7287600

  7. Optimal Disruption of Complex Networks

    CERN Document Server

    Zhao, Jin-Hua

    2016-01-01

    The collection of all the strongly connected components in a directed graph, among each cluster of which any node has a path to another node, is a typical example of the intertwining structure and dynamics in complex networks, as its relative size indicates network cohesion and it also composes of all the feedback cycles in the network. Here we consider finding an optimal strategy with minimal effort in removal arcs (for example, deactivation of directed interactions) to fragment all the strongly connected components into tree structure with no effect from feedback mechanism. We map the optimal network disruption problem to the minimal feedback arc set problem, a non-deterministically polynomial hard combinatorial optimization problem in graph theory. We solve the problem with statistical physical methods from spin glass theory, resulting in a simple numerical method to extract sub-optimal disruption arc sets with significantly better results than a local heuristic method and a simulated annealing method both...

  8. Disrupting the habit of interviewing

    Directory of Open Access Journals (Sweden)

    Eileen Honan

    2014-06-01

    Full Text Available This paper contributes to the growing domain of ‘post-qualitative’ research and experiments with a new (representational form to move away from traditional and clichéd descriptions of research methods. In this paper, I want to interrogate the category of interview, and the habit of interviewing, to disrupt the clichés, so as to allow thinking of different ways of writing/speaking/representing the interactions between researcher and researched that will breathe new life into qualitative inquiries. I will attempt to flatten and shred, destabilise and disrupt our common-sense ideas about interview, including those held most sacred to the qualitative community, that of anonymity and confidentiality, as well as the privilege of the ‘transcript’ in re-presenting interview data.

  9. Disruptive technologies in higher education

    Directory of Open Access Journals (Sweden)

    Michael Flavin

    2012-08-01

    Full Text Available This paper analyses the role of “disruptive” innovative technologies in higher education. In this country and elsewhere, Higher Education Institutions (HEIs have invested significant sums in learning technologies, with Virtual Learning Environments (VLEs being more or less universal, but these technologies have not been universally adopted and used by students and staff. Instead, other technologies not owned or controlled by HEIs are widely used to support learning and teaching. According to Christensen's theory of Disruptive Innovation, these disruptive technologies are not designed explicitly to support learning and teaching in higher education, but have educational potential. This study uses Activity Theory and Expansive Learning to analyse data regarding the impact of disruptive technologies. The data were obtained through a questionnaire survey about awareness and use of technologies, and through observation and interviews, exploring participants’ actual practice. The survey answers tended to endorse Disruptive Innovation theory, with participants establishing meanings for technologies through their use of them, rather than in keeping with a designer's intentions. Observation revealed that learners use a narrow range of technologies to support learning, but with a tendency to use resources other than those supplied by their HEIs. Interviews showed that participants use simple and convenient technologies to support their learning and teaching. This study identifies a contradiction between learning technologies made available by HEIs, and technologies used in practice. There is no evidence to suggest that a wide range of technologies is being used to support learning and teaching. Instead, a small range of technologies is being used for a wide range of tasks. Students and lecturers are not dependent on their HEIs to support learning and teaching. Instead, they self-select technologies, with use weighted towards established brands. The

  10. Thyroid effects of endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Boas, Malene; Feldt-Rasmussen, Ulla; Main, Katharina M

    2012-01-01

    In recent years, many studies of thyroid-disrupting effects of environmental chemicals have been published. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing organism may have deleterious effects on neurological outcome. Chemicals may exert ...... thyroid-disrupting effects, and there is emerging evidence that also phthalates, bisphenol A, brominated flame retardants and perfluorinated chemicals may have thyroid disrupting properties....

  11. HOW TO IDENTIFY DISRUPTIVE NEW BUSINESSES

    OpenAIRE

    Elizabeth Robles

    2015-01-01

    In almost any industry, the most dramatic stories of growth and success were launched from a platform of disruptive innovation (Christensen et al., 2002). The probability of creating a successful, new growth business is 10 times greater if the innovators pursue a disruptive strategy rather than a sustaining one. Genuinely disruptive innovations are the ones that result in the creation of entirely new markets and business models. Few companies have introduced these innovations. Disruptive inno...

  12. Pain catastrophizing and interpersonal problems: a circumplex analysis of the communal coping model.

    Science.gov (United States)

    Lackner, Jeffrey M; Gurtman, Michael B

    2004-08-01

    Using the circumplex model of interpersonal behavior [Handbook of research methods in clinical psychology, 1982], this study tested the communal coping model of catastrophizing (CCM) in a large (N = 179) sample of patients with irritable bowel syndrome (IBS), a common, benign chronic pain disorder associated with significant painful extraintestinal comorbidity (e.g. headache, low back pain). Patients completed the Coping Strategies Questionnaire, the Brief Symptom Inventory, and the Inventory of Interpersonal Problems. The main findings were: (1) individuals who reported higher levels of catastrophizing described greater interpersonal problems; (2) the interpersonal problems described by catastrophizers fell within the friendly and friendly submissive quadrants of the circumplex supporting the notion that they have an interpersonal style demanding support and care-taking [Pain 103 (2003) 151]; (3) the pain coping behavior most strongly associated with interpersonal problems was catastrophizing; and (4) the relationship between interpersonal problems and catastrophizing remained after removing the influence of general symptomatic distress (i.e. an overall tendency to complain of psychological problems in general). In general, data provide evidence supporting the interpersonal distinctiveness of pain catastrophizing as postulated by the CCM. Advantages of a circumplex model and of interpersonal theory for understanding and testing the CCM are discussed. PMID:15288400

  13. Relationships Between Refraining From Catastrophic Thinking, Repetitive Negative Thinking, and Psychological Distress.

    Science.gov (United States)

    Sugiura, Tomoko; Sugiura, Yoshinori

    2016-10-01

    Skills to refrain from catastrophic thinking were negatively related to worry and a wide range of psychological distress. Repetitive negative thinking (including worry) is proposed as a common etiological factor for a wide range of psychological distress. Therefore, reduced repetitive negative thinking would mediate the negative relation between refraining from catastrophic thinking and psychological distress (depression, social anxiety, phobia, generalized anxiety, and obsessions and compulsions). As an overlap between five indices of psychological distress was expected, we first computed latent factors underlying them, which were then predicted by refraining from catastrophic thinking and repetitive negative thinking. Cross-sectional questionnaire data from 125 nonclinical voluntarily participating students (M age = 19.0 years, SD = 3.6; 54% women) supported the predictions: refraining from catastrophic thinking was negatively correlated with depression, social anxiety, phobia, generalized anxiety, and obsession and compulsion. Repetitive negative thinking mediated the negative relationship between refraining from catastrophic thinking and latent factors underlying psychological distress (Fear and Distress). Refraining from catastrophic thinking may be negatively correlated with psychological distress due to its negative relation to repetitive negative thinking. PMID:27511967

  14. Catastrophic Health Expenditure and Household Impoverishment: a case of NCDs prevalence in Kenya

    Directory of Open Access Journals (Sweden)

    Daniel Mwai

    2016-03-01

    Full Text Available Introduction and problem: Non-Communicable Diseases (NCDs have become one of the leading causes of morbidity and mortality in Kenya. Their claim on financial and time resources adversely affects household welfare. Health care cost for NCDs in Kenya is predominantly paid by households as OOP. Health expenditure on NCD stands at 6.2% of Total Health Expenditure which is 0.4 % of the total gross domestic product of the country. This expenditure scenario could have implications on household welfare through catastrophic expenditure in Kenya. Most studies done on catastrophic expenditure in Kenya have not looked at the effect of NCD on poverty. Methodology: The paper has investigated the determinants of catastrophic health spending in a household with special focus on the NCDs. It has also investigated the effect of catastrophic expenditure on household welfare.A National household level survey data on expenditure and utilization is used. Controlling for endogeneity, the results revealed that NCDs and communicable diseases contribute significantly to the likelihood of a household incurring catastrophic expenditure. Results: Although all types of sicknesses have negative effects on household welfare, NCDs have more severe impacts on impoverishment. Policy wise, government and development partners should put in place a health financing plan entailing health insurance and resource pooling as a mean towards social protection. Key words:  Non-Communicable Diseases (NCD, Catastrophic Health Expenditure, endogeneity Impoverishment

  15. Polymorphism in serotonin receptor 3B is associated with pain catastrophizing.

    Directory of Open Access Journals (Sweden)

    Emilia Horjales-Araujo

    Full Text Available Pain catastrophizing, a coping style characterized by excessively negative thoughts and emotions in relation to pain, is one of the psychological factors that most markedly predicts variability in the perception of pain; however, only little is known about the underlying neurobiology. The aim of this study was to test for associations between psychological variables, such as pain catastrophizing, anxiety and depression, and selected polymorphisms in genes related to monoaminergic neurotransmission, in particular serotonin pathway genes. Three hundred seventy-nine healthy participants completed a set of psychological questionnaires: the Pain Catastrophizing Scale (PCS, the State-Trait Anxiety Inventory and Beck's Depression Inventory, and were genotyped for 15 single nucleotide polymorphisms (SNPs in nine genes. The SNP rs1176744 located in the serotonin receptor 3B gene (5-HTR3B was found to be associated with pain catastrophizing scores: both the global score and the subscales of magnification and helplessness. This is the first study to show an association between 5-HTR3B and PCS scores, thus suggesting a role of the serotonin pathway in pain catastrophizing. Since 5-HTR3B has previously been associated with descending pain modulation pathways, future studies will be of great interest to elucidate the molecular pathways involved in the relation between serotonin, its receptors and pain catastrophizing.

  16. Scaling single-state variable catastrophe functions: an application to two-phase natural circulation

    International Nuclear Information System (INIS)

    In this paper I present transformation laws to scale physical processes governed by polynomial equations. Of particular importance is the class of polynomials which describe catastrophe functions. Many important, stability-related, thermal hydraulic phenomena are described by these catastrophe functions, including flooding, two-phase natural circulation, and critical heat flux. Catastrophe functions can be used to define the boundaries of stable system behavior. If a process evolves such that one of these boundaries are crossed, it will undergo a discontinuity which radically alters its evolution (i.e. morphogenesis). By scaling these catastrophe functions, processes exhibiting discontinuous behavior can be studied in scaled test models rather than experimenting with a full-scale, and typically very expensive, prototype. To illustrate their usefulness, the catastrophe function transformation laws are applied to the practical problem of scaling two-phase fluid natural circulation. In addition, the catastrophe manifold for two-phase fluid natural circulation is developed and evaluated to obtain a criterion for the onset of flow instability. ((orig.))

  17. Compositional threshold for Nuclear Waste Glass Durability

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Albert A. [Pacific Northwest National Lab., Richland, WA (United States); Farooqi, Rahmatullah [Pohang Univ. of Science and Technology, (Korea, Republic of); Hrma, Pavel R. [Pacific Northwest National Lab., Richland, WA (United States), Pohang Univ. of Science and Technology, (Korea, Republic of)

    2013-04-24

    Within the composition space of glasses, a distinct threshold appears to exist that separates "good" glasses, i.e., those which are sufficiently durable, from "bad" glasses of a low durability. The objective of our research is to clarify the origin of this threshold by exploring the relationship between glass composition, glass structure and chemical durability around the threshold region.

  18. Threshold Concepts in Finance: Student Perspectives

    Science.gov (United States)

    Hoadley, Susan; Kyng, Tim; Tickle, Leonie; Wood, Leigh N.

    2015-01-01

    Finance threshold concepts are the essential conceptual knowledge that underpin well-developed financial capabilities and are central to the mastery of finance. In this paper we investigate threshold concepts in finance from the point of view of students, by establishing the extent to which students are aware of threshold concepts identified by…

  19. Turbulence and disruptions in Tokamaks

    International Nuclear Information System (INIS)

    In the first part of this thesis, the possible explanation of the electron abnormal thermal conductivity with electromagnetic drift modes rather than simply electrostatic is discussed. A variational form is established in non collisional conditions; linear modes principal possibilities are reviewed, then quasilinear theory is used to calculate the transport phenomenon associated to each mode. They are compared to experimental results. Electron abnormal thermal conductibility is not better explained by electromagnetic modes than by electrostatic modes. In the second part, disruptions are examined; experimental manifestations are briefly recalled. Existing interpretations of these phenomenons are reviewed, which are based on magnetic islands non-linear evolution. A detailed analytical study of the case l=1, m=1 is made. Other disruptions are studied; it is shown that the disruptive process is indissociable from sudden apparition of small scale magnetic turbulence. The possibility of such a turbulence is studied. Its predictable effects are compared to experiment. Such a turbulence, is assumed to exist permanently in an attenuated form, which could justify the electronic transport anomalies in quiescent state

  20. Pharmacological disruption of maladaptive memory.

    Science.gov (United States)

    Taylor, Jane R; Torregrossa, Mary M

    2015-01-01

    Many psychiatric disorders are characterized by intrusive, distracting, and disturbing memories that either perpetuate the illness or hinder successful treatment. For example, posttraumatic stress disorder (PTSD) involves such strong reemergence of memories associated with a traumatic event that the individual feels like the event is happening again. Furthermore, drug addiction is characterized by compulsive use and repeated relapse that is often driven by internal memories of drug use and/or by exposure to external stimuli that were associated with drug use. Therefore, identifying pharmacological methods to weaken the strength of maladaptive memories is a major goal of research efforts aimed at finding new treatments for these disorders. The primary mechanism by which memories could be pharmacologically disrupted or altered is through manipulation of memory reconsolidation. Reconsolidation occurs when an established memory is remembered or reactivated, reentering a labile state before again being consolidated into long-term memory storage. Memories are subject to disruption during this labile state. In this chapter we will discuss the preclinical and clinical studies identifying potential pharmacological methods for disrupting the integrity of maladaptive memory to treat mental illness. PMID:25977090

  1. Engineering analysis of TFTR disruption

    International Nuclear Information System (INIS)

    This report covers an engineering approach quantifying the currents, forces, and times, as well as plasma position, for the worst-case disruption based on engineerign circuit assumptions for the plasma. As the plasma moves toward the wall during the current-decay phase of disruption, the wall currents affect the rate of movement and, hence, the decay time. The calculated structure-induced currents differ considerably from those calculated using a presently available criterion, which specifies that the plasma remains stationary in the center of the torus while decaying in 10 ms. This report outlines the method and basis for the engineering calculation used to determine the current and forces as a function of the circuit characteristics. It provides specific calculations for the Tokamak Fusion Test Reactor (TFTR) with variations in parameters such as the thermal decay time, the torus resistance, and plasma temperature during the current decay. The study reviews possible ways to reduce the disruption damage of TFTR by reducing the magnitude of the plasma external field energy that is absorbed by the plasma during the current decay

  2. The disruptive instability in Tokamak plasmas

    NARCIS (Netherlands)

    Salzedas, F.J.B.

    2001-01-01

    Studies performed in RTP (Rijnhuizen Tokamak Project) of the most violent and dangerous instability in tokamak plasmas, the major disruption, are presented. A particular class of disruptions is analyzed, namely the density limit disruption, which occur in high density plasmas. The radiative te

  3. Threshold enhancement of diphoton resonances

    CERN Document Server

    Bharucha, Aoife; Goudelis, Andreas

    2016-01-01

    The data collected by the LHC collaborations at an energy of 13 TeV indicates the presence of an excess in the diphoton spectrum that would correspond to a resonance of a 750 GeV mass. The apparently large production cross section is nevertheless very difficult to explain in minimal models. We consider the possibility that the resonance is a pseudoscalar boson $A$ with a two--photon decay mediated by a charged and uncolored fermion having a mass at the $\\frac12 M_A$ threshold and a very small decay width, $\\ll 1$ MeV; one can then generate a large enhancement of the $A\\gamma\\gamma$ amplitude which explains the excess without invoking a large multiplicity of particles propagating in the loop, large electric charges and/or very strong Yukawa couplings. The implications of such a threshold enhancement are discussed in two explicit scenarios: i) the Minimal Supersymmetric Standard Model in which the $A$ state is produced via the top quark mediated gluon fusion process and decays into photons predominantly through...

  4. Investigation of Shapes and Spins of Reaccumulated Remnants from Asteroid Disruption Simulations

    Science.gov (United States)

    Michel, Patrick; Ballouz, R.; Richardson, D. C.; Schwartz, S. R.

    2012-10-01

    Evidence that asteroids larger than a few hundred meters diameter can be gravitational aggregates of smaller, cohesive pieces comes, for instance, from images returned by the Hayabusa spacecraft of asteroid 25143 Itokawa (Fujiwara et al., 2006, Science 312, 1330). These images show an irregular 500-meter-long body with a boulder-strewn surface, as might be expected from reaccumulation following catastrophic disruption of a larger parent asteroid (Michel et al., 2001, Science 294, 1696). However, numerical simulations of this process to date essentially focus on the size/mass and velocity distributions of reaccumulated fragments, matching asteroid families. Reaccumulation was simplified by merging the objects into growing spheres. However, understanding shapes, spins and surface properties of gravitational aggregates formed by reaccumulation is required to interpret information from ground-based observations and space missions. E.g., do boulders on Itokawa originate from reaccumulation of material ejected from a catastrophic impact or from other processes (such as the Brazil-nut effect)? How does reaccumulation affect the observed shapes? A model was developed (Richardson et al., 2009, Planet. Space Sci. 57, 183) to preserve shape and spin information of reaccumulated bodies in simulations of asteroid disruption, by allowing fragments to stick on contact (and optionally bounce or fragment further, depending on user-selectable parameters). Such treatments are computationally expensive, and we could only recently start to explore the parameter space. Preliminary results will be presented, showing that some observed surface and shape features may be explained by how fragments produced by a disruption reaccumulate. Simulations of rubble pile collisions without particle cohesion, and an investigation of the influence of initial target rotation on the outcome will also be shown. We acknowledge the National Science Foundation (AST1009579) and NASA (NNX08AM39G).

  5. Thresholds in vegetation responses to drought: Implications for rainfall-runoff modeling

    Science.gov (United States)

    Tague, C.; Dugger, A. L.

    2011-12-01

    While threshold behavior is often associated with soil and subsurface runoff generation, dynamic vegetation responses to water stress may be an important contributor to threshold type behavior in rainfall runoff models. Vegetation water loss varies with vegetation type and biomass and transpiration dynamics in many settings are regulated by stomatal function. In water limited environments the timing and frequency of stomatal closure varies from year to year as a function of water stress. Stomatal closure and associated fine time scale (hourly to weekly) plant transpiration may appear as threshold (on/off) behavior. Total seasonal to annual plant water use, however, typically show a continuous relationship with atmospheric conditions and soil moisture. Thus while short-time scale behavior may demonstrate non-linear, threshold type behavior, continuous relationships at slightly longer time scales can be used to capture the role of vegetation mediated water loss and its associated impact on storage and runoff. Many rainfall runoff models rely on these types of relationships. However these relationships may change if water stress influences vegetation structure as it does in drought conditions. Forest dieback under drought is a dramatic example of a threshold event, and one that is expected to occur with increasing frequency under a warmer climate. Less dramatic but still important are changes in leaf and root biomass in response to drought. We demonstrate these effects using a coupled ecosystem carbon cycling and hydrology model and show that by accounting for drought driven changes in vegetation dynamics we improve our ability to capture inter-annual variation in streamflow for a semi-arid watershed in New Mexico. We also use the model to predict spatial patterns of more catastrophic vegetation dieback with moisture stress and show that we can accurately capture the spatial pattern of ponderosa pine dieback during a early 2000s drought in New Mexico. We use these

  6. Sensitization of catastrophic cognition in cognitive-behavioral therapy for panic disorder

    Directory of Open Access Journals (Sweden)

    Kataoka Miyako

    2007-12-01

    Full Text Available Abstract Background Cognitive model of panic disorder have proposed that panic attacks result from the catastrophic misinterpretation of certain bodily sensations. Cognitive-Behavioral Therapy (CBT for panic disorder aims to change these catastrophic cognitions. CBT intervention successfully caused reduction of catastrophic cognitions and symptomatic improvement in the majority of cases. However there are some patients who fail to modify their catastrophic cognitions or rather experience an increase in them during CBT treatment. It is clinically and theoretically important to understand about cognitive sensitization of panic disorder during CBT sessions. The purpose of the present study is 1 to clarify the baseline characteristics of panic patients who would experience sensitization of their catastrophic cognitions through the CBT treatment, and 2 to examine the course of symptomatic changes for them. Methods Of ninety-five outpatients with panic disorder started the group CBT program for treatment of panic disorder, seventy-nine completer were classified as "cognitively sensitized (CS" or "cognitive responding (CR" or "no-responder" according to the difference of the Agoraphobic Cognitions Questionnaire score across treatment. We compared the CS and CR patients in terms of their baseline clinical characteristics. Then we assessed the symptomatic and functional changes for both groups. Results At the start of the CBT program, despite of the same degree of panic disorder severity, CS scored significantly lower on ACQ score than CR. CS also showed significantly lower score on anticipatory anxiety compared to CR. At the end of treatment CS showed significant improvement in severity of panic disorder, although the degree of improvement was smaller than that for CR. Then CS would progressively reduce their agoraphobic fear and avoidance, and would improve their functional impairment up to three month of follow-up. Conclusion Panic patients who would

  7. The efficacy of stream power and flow duration on geomorphic responses to catastrophic flooding

    Science.gov (United States)

    Magilligan, F. J.; Buraas, E. M.; Renshaw, C. E.

    2015-01-01

    Geomorphologists have long studied the impacts of extreme floods, yet the association between the magnitude of flow parameters (discharge, velocity, shear stress, or stream power) and resulting geomorphic effectiveness remains vague and non-deterministic. Attempts have been made to include flow duration and total expenditure of stream power, in combination with peak unit stream power, as important variables, but there has been minimal exploration of this hydraulic combination. Taking advantage of Tropical Storm Irene's rapid track through eastern Vermont (USA) in late summer 2011, this paper presents the array of geomorphic responses to a short duration (time to peak of theory concerning the role of, and trade-off between, the magnitude of energy expenditure during a flood and its duration. Focusing on a detailed field effort within the 187-km2 Saxtons River basin in southeastern VT, augmented by select sites along the adjacent lower gradient Williams River (291-km2), we elucidate (1) the geomorphic effects of a short duration flood in a humid, well-vegetated landscape; (2) the relationship between geomorphic response and (a) peak stream power, (b) total stream power, and (c) flow duration of stream power above a critical threshold; and (3) the spatial variation of geomorphic effects relative to reach-scale geologic and geomorphic controls. Flooding associated with Tropical Storm Irene ranged from the 1000 year recurrence interval (RI) flood (based on Weibull flood frequency analysis) to the 300 year RI flood (log Pearson Type III). Discharges spawned a peak unit stream power of 712 W/m2 (Saxtons River) and 361 W/m2 (Williams River), with total energy expenditure throughout the event of ~ 16,000 × 103 and 15,000 × 103 J, respectively. For the Saxtons River, channel widening was spatially infrequent and limited in magnitude; however, other geomorphic effects were profound (1) the entrainment, transport, and deposition of extremely coarse material; (2) stripping of

  8. Science for decision making: Transmitting hazard science using catastrophic scenarios

    Science.gov (United States)

    Wein, A.

    2010-12-01

    The ShakeOut and ARkStorm scenarios are scientifically-based, multi-disciplinary efforts to describe the damages and consequences of large, but plausible, natural disasters for use in emergency management and other planning. The ShakeOut earthquake scenario, completed in 2008, posits the occurrence of a major earthquake on the southern San Andreas Fault. It was used by more than 5,000 emergency personnel in a California statewide exercise, and it underpins the Federal Emergency Management Agency’s (FEMA) Catastrophic Plan for Southern California. The ARkStorm winter storm scenario, to be completed in 2010, posits the occurrence of a statewide disaster like the storm that occurred during 1861-1862. The ARkStorm scenario will culminate with two planning summits comprised of federal and state agencies, because such an event would exceed local response and recovery capabilities. This talk will address the following questions that are critical to transmitting science for decision making with examples and observations from the two scenarios: 1) Who are the end users of the scenarios, what types of decisions can scenarios inform, and how are stakeholders engaged? 2) What forms of information and processes work best to communicate and apply the hazard science? 3) What are the challenges of using science in decision making? 4) What future directions shall we pursue? From my perspective as coordinator of economic consequences analyses for the two scenarios, I will share insights to these questions. Framing stakeholder decisions in terms of scale (e.g., household to State) and disaster phase (e.g., emergency response, recovery, and mitigation) allows us to align methods of stakeholder engagement with stakeholder decision making. For these regional-scale scenarios, the methods of engagement included stakeholder participation in project vision, scenario construction workshops, presentations, conferences, and emergency response and recovery exercises. Champions (self

  9. Threshold Signature Scheme Based on Discrete Logarithm and Quadratic Residue

    Institute of Scientific and Technical Information of China (English)

    FEI Ru-chun; WANG Li-na

    2004-01-01

    Digital signature scheme is a very important research field in computer security and modern cryptography.A(k,n) threshold digital signature scheme is proposed by integrating digital signature scheme with Shamir secret sharing scheme.It can realize group-oriented digital signature, and its security is based on the difficulty in computing discrete logarithm and quadratic residue on some special conditions.In this scheme, effective digital signature can not be generated by any k-1 or fewer legal users, or only by signature executive.In addition, this scheme can identify any legal user who presents incorrect partial digital signature to disrupt correct signature, or any illegal user who forges digital signature.A method of extending this scheme to an Abelian group such as elliptical curve group is also discussed.The extended scheme can provide rapider computing speed and stronger security in the case of using shorter key.

  10. Orientability thresholds for random hypergraphs

    CERN Document Server

    Gao, Pu

    2010-01-01

    Let $h>w>0$ be two fixed integers. Let $\\orH$ be a random hypergraph whose hyperedges are all of cardinality $h$. To {\\em $w$-orient} a hyperedge, we assign exactly $w$ of its vertices positive signs with respect to the hyperedge, and the rest negative. A $(w,k)$-orientation of $\\orH$ consists of a $w$-orientation of all hyperedges of $\\orH$, such that each vertex receives at most $k$ positive signs from its incident hyperedges. When $k$ is large enough, we determine the threshold of the existence of a $(w,k)$-orientation of a random hypergraph. The $(w,k)$-orientation of hypergraphs is strongly related to a general version of the off-line load balancing problem. The graph case, when $h=2$ and $w=1$, was solved recently by Cain, Sanders and Wormald and independently by Fernholz and Ramachandran, which settled a conjecture of Karp and Saks.

  11. Instability Threshold “Hysteresis”

    Directory of Open Access Journals (Sweden)

    Agnes Muszynska

    1999-01-01

    Full Text Available The transient process which starts at the instability threshold of a rotor rotating in a fluid environment, and ends up in the limit cycle of self-excited vibrations known as fluid whirl or fluid whip, is discussed in this paper. A one-lateral-mode, isotropic, nonlinear model of the rotor with fluid interaction allows for exact particular solutions and an estimation of the transient process. The fluid interacting with the rotor is contained in a small radial clearance area, such as in bearings, seals, or rotor-to-stator clearances, and its effects are represented by fluid film radial stiffness, damping, and fluid inertia rotating at a different angular velocities.

  12. Astronomy below the Survey Threshold

    CERN Document Server

    Zwart, Jonathan T L; Karim, Alexander; Jackson, Carole; Norris, Ray; Condon, Jim; Afonso, Jose; Heywood, Ian; Jarvis, Matt; Navarrete, Felipe; Prandoni, Isabella; Rigby, Emma; Rottgering, Huub; Santos, Mario; Sargent, Mark; Seymour, Nick; Taylor, Russ; Vernstrom, Tessa

    2014-01-01

    Astronomy at or below the 'survey threshold' has expanded significantly since the publication of the original 'Science with the Square Kilometer Array' in 1999 and its update in 2004. The techniques in this regime may be broadly (but far from exclusively) defined as 'confusion' or 'P(D)' analyses (analyses of one-point statistics), and 'stacking', accounting for the flux-density distribution of noise-limited images co-added at the positions of objects detected/isolated in a different waveband. Here we discuss the relevant issues, present some examples of recent analyses, and consider some of the consequences for the design and use of surveys with the SKA and its pathfinders.

  13. Crossing thresholds: Analysis of hazardous tipping points in alpine catchments

    Science.gov (United States)

    Lutzmann, Silke; Sass, Oliver

    2016-04-01

    Steep mountain channels or torrents in small alpine catchments are characterized by high geomorphic activity with sediment dynamics being inherently nonlinear and threshold-mediated. Localized, high intensity rainstorms can drive torrential systems past a tipping point resulting in a sudden onset of hazardous events like (flash-) flooding, heavy bedload transport or debris flows. Such responses exhibit an abrupt switch in the fluvial system's mode (e.g. transport / supply limited). Changes in functional connectivity may persist beyond the tipping point. Torrential hazards cause costly damage in the densely populated Alpine Region. Thus, there is a rising interest in potential effects of climate change on torrential sediment dynamics. Understanding critical conditions close to tipping points is important to reduce uncertainty in predicting sediment fluxes. In this study we aim at (i) establishing threshold precipitation characteristics for the Eastern Alps of Austria. Precipitation is hypothesized to be the main forcing factor of torrential events. (ii) How do thresholds vary in space and time? (iii) The effect of external triggers is strongly mediated by the internal disposition of catchments to respond. Which internal conditions are critical for susceptibility? (iv) Is there a change in magnitude or frequency in the recent past and what can be expected for the future? The 71 km2 catchment of the river Schöttlbach in the East Alpine Region of Styria (Austria) is monitored since a heavy precipitation event resulted in a catastrophic flood in July 2011. Sediment mobilization from slopes as well as within-channel storage and bedload transport are regularly measured using photogrammetric methods and sediment impact sensors. Thus, detailed knowledge exists on magnitude and spatial propagation of sediment waves through the catchment. The associated hydro-meteorological (pre-) conditions can be inferred from a dense station network. Changing bedload transport rates and

  14. Disruptive Innovation in Numerical Hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Waltz, Jacob I. [Los Alamos National Laboratory

    2012-09-06

    We propose the research and development of a high-fidelity hydrodynamic algorithm for tetrahedral meshes that will lead to a disruptive innovation in the numerical modeling of Laboratory problems. Our proposed innovation has the potential to reduce turnaround time by orders of magnitude relative to Advanced Simulation and Computing (ASC) codes; reduce simulation setup costs by millions of dollars per year; and effectively leverage Graphics Processing Unit (GPU) and future Exascale computing hardware. If successful, this work will lead to a dramatic leap forward in the Laboratory's quest for a predictive simulation capability.

  15. Study of the generation and suppression of runaway currents in provoked disruptions in J-TEXT

    International Nuclear Information System (INIS)

    Runaway currents following disruptions have an important effect on the first wall for the next generation tokamak. The behaviors of runaway currents following intentional provoked disruptions have been investigated in the J-TEXT tokamak. It is found that the runaway current generation following provoked disruptions depends on both the toroidal magnetic field and the plasma current. The conversion efficiency of pre-disruptive plasma currents into runaway currents is in the ranges of 30% to 60% in J-TEXT. The runaway currents can be avoided by the intensive gas puffing of H2 due to the low multiplication factor in J-TEXT. -- Highlights: ► The regime of runaway generation in disruptions in J-TEXT has been established. ► The magnetic field threshold for runaway current generation in disruptions is 2.2 T. ► The conversion efficiency of runaway current is in the ranges of 30% to 60%. ► The runaway currents can be avoided by the intensive gas puffing of H2.

  16. Disruption mitigation experiment on Tore Supra

    International Nuclear Information System (INIS)

    Disruptions can cause serious damages to tokamaks due to the resulting forces on the machine's structures and to the flux of accelerated runaway electrons. Mitigation techniques are thus required. A promising method is massive gas injection (MGI), the impact of this method on runaway electrons has been investigated on Tore-Supra where runaway electrons are observed in a majority of disruptions. Helium has been injected in either stable or pre-disruptive phases. A statistical comparison of several disruptions either spontaneous or triggered by MGI indicates that MGI disruptions are less violent, with a good benefit for machine's structures. Compared to a standard disruption, a MGI disruption enables an easy plasma recovery for the next pulse without noticeable helium pollution of following plasmas. The most important effect of MGI disruptions is the total disappearance of the runaway electron production. The capability of MGI to stop already accelerated electrons has also been investigated, it is shown that MGI is not able to stop already accelerated runaways. This points to the absolute necessity to develop disruption precursor techniques to identify disruptions sufficiently in advance (6-10 ms) to allow MGI to penetrate the plasma core before the current quenches. (A.C.)

  17. Catastrophe Bonds. From Structure to Strategy – A Cluster Analysis at European Level

    Directory of Open Access Journals (Sweden)

    Laura-Gabriela CONSTANTIN

    2014-12-01

    Full Text Available As a core activity and discipline of corporate management and corporate governance, risk management is, especially nowadays, a central part in pursuing the sustainable development desiderates, both from the perspective of the firm and of the society as a whole.Considering the negative impact natural catastrophes have on the companies’ and countries’ competitiveness, the development of sustainable financial products that make a contribution to transferring the risk and allocating the capital in case of disasters stands for a continual preoccupation, especially for the (reinsurance industry, while the study of catastrophe bonds – insurance-linked securities – is of interest in the specialized literature. In this context, the scope of the present research is to expand the empirical studies within this field while examining the link between the structure of the catastrophe bonds and the risk management approach employed while accessing the capital markets through this transactions.The methodology entailed clustering a selection of transactions developed by European cedents based on the size of each issue and correlating the results with an innovative score, developed to encompass several important catastrophe bonds structural components.The findings reflect that the general structural elements of the financial transactions reflect closely the corporate approach regarding the innovative risk intermediation instruments for the examined catastrophe bonds deals. The outcomes also emphasize, as expected, that companies with a stronger presence on this market seem to have a more sophisticated risk management approach.

  18. Catastrophic phase transitions and early warnings in a spatial ecological model

    International Nuclear Information System (INIS)

    Gradual changes in exploitation, nutrient loading, etc produce shifts between alternative stable states (ASS) in ecosystems which, quite often, are not smooth but abrupt or catastrophic. Early warnings of such catastrophic regime shifts are fundamental for designing management protocols for ecosystems. Here we study the spatial version of a popular ecological model, involving a logistically growing single species subject to exploitation, which is known to exhibit ASS. Spatial heterogeneity is introduced by a carrying capacity parameter varying from cell to cell in a regular lattice. Transport of biomass among cells is included in the form of diffusion. We investigate whether different quantities from statistical mechanics—like the variance, the two-point correlation function and the patchiness—may serve as early warnings of catastrophic phase transitions between the ASS. In particular, we find that the patch-size distribution follows a power law when the system is close to the catastrophic transition. We also provide links between spatial and temporal indicators and analyse how the interplay between diffusion and spatial heterogeneity may affect the earliness of each of the observables. We find that possible remedial procedures, which can be followed after these early signals, become more effective as the diffusion becomes lower. Finally, we comment on similarities of and differences between these catastrophic shifts and paradigmatic thermodynamic phase transitions like the liquid–vapour change of state for a fluid like water

  19. Catastrophe model and its experimental verification of static loading rock system under impact load

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    According to the catastrophe model for impact buckling of static loading structures, a new catastrophe model for impact loading failure of a static loading rock system was established, and one dimension (1D) catastrophe model was analyzed. The analysis results indicate that the furcation collection where catastrophe may take place is not only decided by mechanical system itself but also relates to exterior loading, which is different from the results obtained under mono-static loading where the bifurcation collection is only determined by mechanics of the system itself and has nothing to do with exterior loading. In addition, the corresponding 1D coupled static-dynamic loading experiment is designed to verify the analysis results of catastrophe model The test is done with Instron 1342 electroservo controlled testing system, in which medium strain rate is caused by monotony rising dynamic load. The parameters are obtained combining theoretical model with experiment. The experimental and theoretical curves of critical dynamic load vs static load are rather coincided, thus the new model is proved to be correct.

  20. Catastrophic Outcomes in Free Tissue Transfer: A Six-Year Review of the NSQIP Database

    Directory of Open Access Journals (Sweden)

    David W. Grant

    2014-01-01

    Full Text Available Background. No studies report robust data on the national incidence and risk factors associated with catastrophic medical outcomes following free tissue transfer. Methods. The American College of Surgeons (ACS multicenter, prospective National Surgical Quality Improvement Program (NSQIP database was used to identify patients who underwent free tissue transfer between 2006 and 2011. Multivariable logistic regression was used for statistical analysis. Results. Over the 6-year study period 2,349 patients in the NSQIP database underwent a free tissue transfer procedure. One hundred and twenty-two patients had at least one catastrophic medical outcome (5.2%. These 122 patients had 151 catastrophic medical outcomes, including 93 postoperative respiratory failure events (4.0%, 14 pulmonary emboli (0.6%, 13 septic shock events (0.5%, 12 myocardial infarctions (0.5%, 6 cardiac arrests (0.3%, 4 strokes (0.2%, 1 coma (0.0%, and 8 deaths (0.3%. Total length of hospital stay was on average 14.7 days longer for patients who suffered a catastrophic medical complication (P<0.001. Independent risk factors were identified. Conclusions. Free tissue transfer is a proven and safe technique. Catastrophic medical complications were infrequent but added significantly to length of hospital stay and patient morbidity.

  1. Cross-cultural adaptation and validation of the Norwegian pain catastrophizing scale in patients with low back pain

    OpenAIRE

    Fernandes Linda; Storheim Kjersti; Lochting Ida; Grotle Margreth

    2012-01-01

    Background Pain catastrophizing has been found to be an important predictor of disability and days lost from work in patients with low back pain. The most commonly used outcome measure to identify pain catastrophizing is the Pain Catastrophizing Scale (PCS). To enable the use of the PCS in clinical settings and research in Norwegian speaking patients, the PCS had to be translated. The purpose of this study was therefore to translate and cross-culturally adapt the PCS into N...

  2. The influence of catastrophizing on treatment outcome in patients with non-specific low back pain: A systematic review

    OpenAIRE

    Wertli, Maria M; Burgstaller, Jakob M.; Weiser, Sherri; Steurer, Johann; Kofmehl, Reto; Held, Ulrike

    2014-01-01

    Study Design. Systematic reviewObjective. The aim of the current study was to assess the effect of catastrophizing on treatment efficacy and outcome in patients treated for low back pain.Summary of Background Data. Psychological factors including catastrophizing thoughts are believed to increase the risk for chronic low back pain. The influence of catastrophizing is debated.Methods. In September 2012 the following databases were searched: BIOSIS, CINAHL, Cochrane Library, Embase, OTSeeker, Pe...

  3. Pain-related Catastrophizing and Perceived Social Responses: Inter-relationships in the Context of Chronic Pain

    OpenAIRE

    Buenaver, Luis F.; Edwards, Robert R.; Haythornthwaite, Jennifer A.

    2006-01-01

    Pain-related coping, particularly catastrophizing, plays a significant role in shaping pain responses. One way catastrophizing is hypothesized to amplify pain and disability is via its effect on patients, social environments (e.g., communal coping model), though empirical support is limited. The present study tested whether the association between catastrophizing and deleterious pain-related outcomes was mediated by patients’ perceptions of significant others’ responses to their pain in a sam...

  4. Association between catastrophizing and self-rated pain and disability in patients with chronic low back pain

    OpenAIRE

    K. Meyer; Tschopp, A.; Sprott, H; Mannion, A. F.

    2009-01-01

    BACKGROUND: Catastrophizing plays an important role in models of pain chronicity, showing a consistent correlation with both pain intensity and disability. It is conceivable that these associations are mediated or confounded by other psychological attributes. OBJECTIVE: To examine the relative influence of catastrophizing and other psychological variables on pain and disability in patients with chronic low back pain. METHODS: Seventy-eight patients completed the Pain Catastrophizing Scale, Ro...

  5. On the implications of thresholds for economic science and environmental policy

    Energy Technology Data Exchange (ETDEWEB)

    Aalbers, R.

    1999-05-11

    This thesis consists of four chapters on the topic of thresholds. Chapter 2 deals with the issue of a truly catastrophic threshold. Society has perfect information on both the location and the impact of crossing the threshold. The assumption is made that crossing the threshold will result in the destruction of all human utility on earth (which is not the same as the destruction of all human life on earth). On the basis of a simple neoclassical growth model the question is posed under what conditions society would like to cross the threshold, and hence, initiate a catastrophe. The trade-off for society is to have a relatively low consumption level for an infinite period of time, or to have a relatively high consumption level for a short period of time. Perhaps surprisingly, it turns out that the doomsday scenario may be optimal (in the sense of maximizing human utility). Chapter 3 extends the analysis of the second chapter by allowing society to spend resources either on consumption or on abatement. In chapter 4 the assumption of certainty of information about both the location and the impact of a threshold is relaxed. Instead it is assumed that a society has information - in the form of a probability density function - about both the location of the threshold and its impact. What then is the optimal strategy for that society? In addition, it will be analysed how society`s optimal strategy changes, if the uncertainty increases. We will see that if uncertainty about the impact of the threshold increases, society`s strategy will become more prudent. Moreover, it is argued that any form of cost-benefit analysis must - whenever thresholds cannot be excluded a priori from the analysis - necessarily be based on arbitrary, in the sense of non-empirically verifiable, assumptions about the shape of the damage function. Finally, the author examines the case in which society has not enough - quantitative or qualitative - information in order to obtain, or estimate, a

  6. Iran: the next nuclear threshold state?

    OpenAIRE

    Maurer, Christopher L.

    2014-01-01

    Approved for public release; distribution is unlimited A nuclear threshold state is one that could quickly operationalize its peaceful nuclear program into one capable of producing a nuclear weapon. This thesis compares two known threshold states, Japan and Brazil, with Iran to determine if the Islamic Republic could also be labeled a threshold state. Furthermore, it highlights the implications such a status could have on U.S. nonproliferation policy. Although Iran's nuclear program is mir...

  7. VIBRATORY THRESHOLDS AND MOBILITY IN OLDER PERSONS

    OpenAIRE

    Buchman, Aron S; Wilson, Robert S.; Leurgans, Sue; David A Bennett

    2009-01-01

    We tested the hypothesis that vibratory thresholds in the elderly are related to mobility. 629 older persons without dementia underwent testing including 11 lower extremity performance measures and modified UPDRS, summarized as composite mobility and global Parkinsonian signs. Vibratory thresholds were measured at the ankle and toes bilaterally using the graduated Rydel-Seiffer tuning fork. In linear regression models adjusted for age, sex and education, vibratory threshold was associated wit...

  8. Threshold Effects of Energy Price Changes

    International Nuclear Information System (INIS)

    This paper presents a theoretical model emphasising energy investments' characteristics of uncertainty and irreversibility. The theoretical model suggests threshold effects. Firms are induced to substitute away from energy only if prices of energy exceed a certain threshold level and they reverse the technology only if energy prices are low enough. Estimating a simple investment relation using panel data for the Dutch economy, we find evidence for threshold effects. 23 refs

  9. Public policy and risk financing strategies for global catastrophe risk management - the role of global risk initiatives

    Science.gov (United States)

    McSharry, Patrick; Mitchell, Andrew; Anderson, Rebecca

    2010-05-01

    Decision-makers in both public and private organisations depend on accurate data and scientific understanding to adequately address climate change and the impact of extreme events. The financial impacts of catastrophes on populations and infrastructure can be offset through effective risk transfer mechanisms, structured to reflect the specific perils and levels of exposure to be covered. Optimal strategies depend on the likely socio-econonomic impact, the institutional framework, the overall objectives of the covers placed and the level of both the frequency and severity of loss potential expected. The diversity of approaches across different countries has been documented by the Spanish "Consorcio de Compensación de Seguros". We discuss why international public/private partnerships are necessary for addressing the risk of natural catastrophes. International initiatives such as the Global Earthquake Model (GEM) and the World Forum of Catastrophe Programmes (WFCP) can provide effective guidelines for constructing natural catastrophe schemes. The World Bank has been instrumental in the creation of many of the existing schemes such as the Turkish Catastrophe Insurance Pool, the Caribbean Catastrophe Risk Insurance Facility and the Mongolian Index-Based Livestock Insurance Program. We review existing schemes and report on best practice in relation to providing protection against natural catastrophe perils. The suitability of catastrophe modelling approaches to support schemes across the world are discussed and we identify opportunities to improve risk assessment for such schemes through transparent frameworks for quantifying, pricing, sharing and financing catastrophe risk on a local and global basis.

  10. Viral-mediated Ntf3 overexpression disrupts innervation and hearing in nondeafened guinea pig cochleae.

    Science.gov (United States)

    Lee, Min Young; Kurioka, Takaomi; Nelson, Megan M; Prieskorn, Diane M; Swiderski, Donald L; Takada, Yohei; Beyer, Lisa A; Raphael, Yehoash

    2016-01-01

    Synaptopathy in the cochlea occurs when the connection between inner hair cells and the auditory nerve is disrupted, leading to impaired hearing and nerve degeneration. Experiments using transgenic mice have shown that overexpression of NT3 by supporting cells repairs synaptopathy caused by overstimulation. To accomplish such therapy in the clinical setting, it would be necessary to activate the neurotrophin receptor on auditory neurons by other means. Here we test the outcome of NT3 overexpression using viral-mediated gene transfer into the perilymph versus the endolymph of the normal guinea pig cochlea. We inoculated two different Ntf3 viral vectors, adenovirus (Adv) or adeno-associated virus (AAV) into the perilymph, to facilitate transgene expression in the mesothelial cells and cochlear duct epithelium, respectively. We assessed outcomes by comparing Auditory brainstem response (ABR) thresholds prior to that at baseline to thresholds at 1 and 3 weeks after inoculation, and then performed histologic evaluation of hair cells, nerve endings, and synaptic ribbons. We observed hearing threshold shifts as well as disorganization of peripheral nerve endings and disruption of synaptic connections between inner hair cells and peripheral nerve endings with both vectors. The data suggest that elevation of NT3 levels in the cochlear fluids can disrupt innervation and degrade hearing. PMID:27525291

  11. Threshold pion electroproduction at large momentum transfers

    International Nuclear Information System (INIS)

    We consider pion electroproduction close to threshold for Q2 in the region 1-10 GeV2 on a nucleon target. The momentum transfer dependence of the S-wave multipoles at threshold, E0+ and L0+, is calculated in the chiral limit using light-cone sum rules. Predictions for the cross sections in the threshold region are given taking into account P-wave contributions that, as we argue, are model independent to a large extent. The results are compared with the SLAC E136 data on the structure function F2(W,Q2) in the threshold region. (orig.)

  12. Percolation Threshold in Polycarbonate Nanocomposites

    Science.gov (United States)

    Ahuja, Suresh

    2014-03-01

    Nanocomposites have unique mechanical, electrical, magnetic, optical and thermal properties. Many methods could be applied to prepare polymer-inorganic nanocomposites, such as sol-gel processing, in-situ polymerization, particle in-situ formation, blending, and radiation synthesis. The analytical composite models that have been put forth include Voigt and Reuss bounds, Polymer nanocomposites offer the possibility of substantial improvements in material properties such as shear and bulk modulus, yield strength, toughness, film scratch resistance, optical properties, electrical conductivity, gas and solvent transport, with only very small amounts of nanoparticles Experimental results are compared against composite models of Hashin and Shtrikman bounds, Halpin-Tsai model, Cox model, and various Mori and Tanaka models. Examples of numerical modeling are molecular dynamics modeling and finite element modeling of reduced modulus and hardness that takes into account the modulus of the components and the effect of the interface between the hard filler and relatively soft polymer, polycarbonate. Higher nanoparticle concentration results in poor dispersion and adhesion to polymer matrix which results in lower modulus and hardness and departure from the existing composite models. As the level of silica increases beyond a threshold level, aggregates form which results in weakening of the structure. Polymer silica interface is found to be weak as silica is non-interacting promoting interfacial slip at silica-matrix junctions. Our experimental results compare favorably with those of nanocomposites of polyesters where the effect of nanoclay on composite hardness and modulus depended on dispersion of nanoclay in polyester.

  13. Efficient threshold for volumetric segmentation

    Science.gov (United States)

    Burdescu, Dumitru D.; Brezovan, Marius; Stanescu, Liana; Stoica Spahiu, Cosmin; Ebanca, Daniel

    2015-07-01

    Image segmentation plays a crucial role in effective understanding of digital images. However, the research on the existence of general purpose segmentation algorithm that suits for variety of applications is still very much active. Among the many approaches in performing image segmentation, graph based approach is gaining popularity primarily due to its ability in reflecting global image properties. Volumetric image segmentation can simply result an image partition composed by relevant regions, but the most fundamental challenge in segmentation algorithm is to precisely define the volumetric extent of some object, which may be represented by the union of multiple regions. The aim in this paper is to present a new method to detect visual objects from color volumetric images and efficient threshold. We present a unified framework for volumetric image segmentation and contour extraction that uses a virtual tree-hexagonal structure defined on the set of the image voxels. The advantage of using a virtual tree-hexagonal network superposed over the initial image voxels is that it reduces the execution time and the memory space used, without losing the initial resolution of the image.

  14. Roots at the percolation threshold

    Science.gov (United States)

    Kroener, Eva; Ahmed, Mutez Ali; Carminati, Andrea

    2015-04-01

    The rhizosphere is the layer of soil around the roots where complex and dynamic interactions between plants and soil affect the capacity of plants to take up water. The physical properties of the rhizosphere are affected by mucilage, a gel exuded by roots. Mucilage can absorb large volumes of water, but it becomes hydrophobic after drying. We use a percolation model to describe the rewetting of dry rhizosphere. We find that at a critical mucilage concentration the rhizosphere becomes impermeable. The critical mucilage concentration depends on the radius of the soil particle size. Capillary rise experiments with neutron radiography prove that for concentrations below the critical mucilage concentration water could easily cross the rhizosphere, while above the critical concentration water could no longer percolate through it. Our studies, together with former observations of water dynamics in the rhizosphere, suggest that the rhizosphere is near the percolation threshold, where small variations in mucilage concentration sensitively alter the soil hydraulic conductivity. Is mucilage exudation a plant mechanism to efficiently control the rhizosphere conductivity and the access to water?

  15. Stable states and catastrophic shifts in tidal eco-morphodynamics

    Science.gov (United States)

    Marani, M.; D'Alpaos, A.; Lanzoni, S.; Carniello, L.; Rinaldo, A.

    2007-12-01

    Changes in relative sea level, nutrient and sediment loading, and ecological characteristics expose tidal landforms and ecosystems to responses which may or may not be reversible. On this basis alone predicting the response of tidal geomorphology is important in view of the ecological, cultural and socio-economic importance of endangered tidal environments worldwide. Here we present a point model of the joint evolution of tidal landforms and biota including the dynamics of intertidal vegetation, benthic microbial assemblages, erosional and depositional processes, local and general hydrodynamics, and relative sea-level change. Alternative stable states and punctuated-equilibrium dynamics emerge, characterized by possible sudden transitions of the system, governed by marine transgressions or regressions, vegetation type, disturbances of the benthic biofilm and sediment availability. Multiple equilibria are the result of the interplay of erosion, deposition and biostabilization, highlighting the importance of the coupling between biological and sediment transport processes in determining the evolution of a tidal system as a whole. Hysteretic switches between stable states may arise because of differences in the threshold values of relative sea level rise inducing transitions from vegetated to unvegetated equilibria and viceversa. A similar hysteretic mechanism is also found to link successive periods of increased and decreased sediment availability.

  16. Catastrophic loss of stratospheric ozone in dense volcanic clouds

    Science.gov (United States)

    Prather, Michael

    1992-01-01

    Rapid, localized loss of ozone is predicted to occur in the midlatitude and tropical stratosphere in the presence of very large concentrations of sulfate aerosols. Volcanic eruptions can increase the effective surface area of sulfuric acid so that heterogeneous reactions involving ClONO2, and secondarily N2O5, are able to suppress NO(x) abundances by more than a factor of 10 relative to gas phase chemistry. When NO(x) levels fall below a threshold, e.g., 0.6 ppb at 24 km in mid-latitudes, the chlorine-catalyzed loss of O3 proceeds at rates comparable to those during the formation of the Antarctic ozone hole, more than 50 ppb per day. If such losses occurred following the eruption of Mount Pinatubo in the most volcanically perturbed regions over the tropics and mid-latitudes, this model predicts that they are driven primarily by the suppression of NO(x) below these critical levels. The increase in stratospheric chlorine since El Chichon has made Mount Pinatubo more than twice as effective in causing rapid O3 loss.

  17. Measured currents in JET limiters during disruptions

    International Nuclear Information System (INIS)

    Structures mounted inside a tokamak must be able to withstand the electromagnetic forces which arise during disruptions of the plasma. This paper reports on halo current measurements in the JET tokamak during disruptions. A toroidally distributed array of current sensing tiles reveal that in many disruptions a high degree of toroidal uniformity exists. However in exceptional disruptions the halo current measured at different toroidal positions varies by more than a factor of 2. This latter class of disruption has been observed to result in an asymmetric displacement of the vacuum vessel. The total halo current is estimated to be up to 15% of the initial plasma current. The halo current width for a particular disruption is estimated to be 8 cm

  18. Plasma characteristics during soft disruptions

    International Nuclear Information System (INIS)

    A significant class of disruptive discharges in tokamaks is characterized by an irreversible but rather slow current decay occurring while the electron temperature is still high. For definitiveness we refer to typical JET cases, where the observed rate of current decay is of the order of 2-3MA/s and the electron temperature Te measured by the ECE polychromator may decay as fast as 6keV/s in the center and 1.5 keV/s at the position of the q=2 surface. The influx of impurities is moderate and Zeff ∼6. The Ohmic resistance ROhm calculated with the proper plasma geometry and the ECE profiles is of the order of 1 μΩ plasma during the disruptive decay and these observations cannot be reconciled with the model of a choking effect of the plasma caused solely by a sudden inflow of impurities which may drive a radiative collapse of the plasma temperature to a few eV on a ms time scale. The discharge evolution is conveniently described by the trajectories on the plane of the parameters li (internal inductance) and q(a) (safety factor). Inspection of the path followed shows that the soft disruption phase often traces backwards the current ramp up phase, where an accelerated peaking up of the current profile may be associated to the effects of observed enhancement of MHD activity, as measured by the poloidal and toroidal magnetic pick-up coils. The observed irreversible process suggests that the effective resistance Reff of the plasma may be due indeed to temperature independent MHD effects. The problem is discussed comparing the difference between the effective and the Ohmic resistances with the expected value of a model based on the coupling of unstable tearing modes with resonant surfaces close together, around the q=2 surface where a saturated background mode is assumed. The time scales of the process observed require that the power input to the plasma be evaluated considering the full coupling with the external active and passive circuit elements since it is incorrect

  19. Quasi-classical approximation in vortex filament dynamics. Integrable systems, gradient catastrophe and flutter

    CERN Document Server

    Konopelchenko, B G

    2012-01-01

    Quasiclassical approximation in the intrinsic description of the vortex filament dynamics is discussed. Within this approximation the governing equations are given by elliptic system of quasi-linear PDEs of the first order. Dispersionless Da Rios system and dispersionless Hirota equation are among them. They describe motion of vortex filament with slow varying curvature and torsion without or with axial flow. Gradient catastrophe for governing equations is studied. It is shown that geometrically this catastrophe manifests as a fast oscillation of a filament curve around the rectifying plane which resembles the flutter of airfoils. Analytically it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painleve' I equation.

  20. Loading-rate-independent delay of catastrophic avalanches in a bulk metallic glass

    Science.gov (United States)

    Chen, S. H.; Chan, K. C.; Wang, G.; Wu, F. F.; Xia, L.; Ren, J. L.; Li, J.; Dahmen, K. A.; Liaw, P. K.

    2016-02-01

    The plastic flow of bulk metallic glasses (BMGs) is characterized by intermittent bursts of avalanches, and this trend results in disastrous failures of BMGs. In the present work, a double-side-notched BMG specimen is designed, which exhibits chaotic plastic flows consisting of several catastrophic avalanches under the applied loading. The disastrous shear avalanches have, then, been delayed by forming a stable plastic-flow stage in the specimens with tailored distances between the bottoms of the notches, where the distribution of a complex stress field is acquired. Differing from the conventional compressive testing results, such a delaying process is independent of loading rate. The statistical analysis shows that in the specimens with delayed catastrophic failures, the plastic flow can evolve to a critical dynamics, making the catastrophic failure more predictable than the ones with chaotic plastic flows. The findings are of significance in understanding the plastic-flow mechanisms in BMGs and controlling the avalanches in relating solids.

  1. Catastrophic Failure and Fault-Tolerant Design of IGBT Power Electronic Converters - An Overview

    DEFF Research Database (Denmark)

    Wu, Rui; Blaabjerg, Frede; Wang, Huai;

    2013-01-01

    Reliability is one of the key issues for the application of Insulated Gate Bipolar Transistors (IGBTs) in power electronic converters. Many efforts have been devoted to the reduction of IGBT wear out failure induced by accumulated degradation and catastrophic failure triggered by single......-event overstress. The wear out failure under field operation could be mitigated by scheduled maintenances based on lifetime prediction and condition monitoring. However, the catastrophic failure is difficult to be predicted and thus may lead to serious consequence of power electronic converters. To obtain a better...... understanding of catastrophic failure of IGBTs, the state-of-the-art research on their failure behaviors and failure mechanisms is presented in this paper. Moreover, various fault-tolerant design methods, to prevent converter level malfunctions in the event of IGBT failure, are also reviewed....

  2. Analgesic effect of perioperative escitalopram in high pain catastrophizing patients after total knee arthroplasty

    DEFF Research Database (Denmark)

    Lunn, Troels H; Frokjaer, Vibe G; Hansen, Torben Bæk;

    2015-01-01

    has not previously been investigated. The authors hypothesized that perioperative escitalopram would reduce pain after TKA in high pain catastrophizing patients. METHODS: A total of 120 pain catastrophizing patients (selected using the pain catastrophizing scale as preoperative screening tool......) scheduled for TKA were randomized in a double-blind manner to either 10 mg escitalopram or placebo daily from preanesthesia to postoperative day 6 in addition to a standardized analgesic regime. The primary outcome was pain upon ambulation 24 h after surgery. Secondary outcomes were overall pain during well......-defined mobilizations and at rest from 2 to 48 h and from days 2 to 6, morphine equivalents, anxiety, depression, and side effects. RESULTS: Pain upon ambulation (mean [95% CI]) 24 h after surgery in the escitalopram versus placebo group was 58 (53 to 64) versus 64 (58 to 69), the mean difference being -5 (-13 to 3), P...

  3. Efficient prevention and compensation of catastrophic risks. The example of damage by nuclear accidents

    International Nuclear Information System (INIS)

    This book deals with the liability for damage due to catastrophic risks. The nuclear liability law serves as an example of such a catastrophic risk. The question that we tried to answer is what an efficient compensation scheme for catastrophic risks should look like. This question is dealt with both from a law and an economic point of view and from a comparative point of view. The main element in comparing the laws in different countries is the comparison between Belgian and Dutch civil (nuclear) liability law. But also American nuclear liability law is part of the analysis (the Price-Anderson Act). The book consists of four parts: (nuclear) civil liability law, legal and economic approach, analysis of other compensation systems and conclusions. The big themes in this book are therefore civil (nuclear) liability law, insurance law and environmental liability law

  4. Evaluation of the propensity for coal spontaneous combustion based on catastrophe theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-tao; ZHANG Xi-chen; TIEN Jerry C; LI Ya-qing

    2011-01-01

    Generally,different prevention measures should be taken according to spontaneous combustion propensities.The current methods to evaluate the propensity of coal spontaneous combustion,such as chromatographic method of oxygen adsorption,oxidation kinetics method and activation energy method,are mostly affected by human factors.Their boundaries among different classes of propensities were all established by subjective judgments.A new evaluation method using catastrophe theory is introduced.This method can accurately depict the process of coal spontaneous combustion and the evaluation index,"catastrophe temperature",be obtained based on the model.In terms of catastrophe temperature,the spontaneous combustion propensity of different coals can be sequenced.Experimental data indicate that this method is appropriate to describe the spontaneous combustion process and to evaluate the propensity of coal spontaneous combustion.

  5. Long-range pulse length scaling of 351 nm laser damage thresholds

    International Nuclear Information System (INIS)

    This paper reports how, in a series of experiments incorporating 351-nm pulselengths of 9, 26, 54, and 625 ns, it was found that laser damage thresholds increased as (pulselength)x, and that the exponent averaged 0.36 and ranged, for different samples, from 0.23 to 0.48. Similar results were obtained when only catastrophic damage was considered. Samples included Al2O3/SiO2 in both AR and HR multilayers. HR's of Sc2O3/SiO2 and HfO2/SiO2, and an Al- on-pyrex mirror; 9-ns thresholds were between 0.2-5.6 J/cm2. When these data were compared with a wide range of other results - for wavelengths from 0.25 to 10.6 μm and pulselengths down to 4 ps - a remarkably consistent picture emerged. Damage thresholds on average, increase approximately as the cube-root of pulselength from picoseconds to nearly a microsecond, and do so regardless of wavelength or material under test

  6. Long-range pulselength scaling of 351nm laser damage thresholds

    Science.gov (United States)

    Foltyn, S. R.; Jolin, L. J.

    1986-12-01

    In a series of experiments incorporating 351nm pulselength of 9, 26, 54, and 625ns, it was found that laser damage thresholds increased as (pulselength)/sup x/, and that the exponent averaged 0.36 and ranged, for different samples, from 0.23 to 0.48. Similar results were obtained when only catastrophic damage was considered. Samples included Al2O3/SiO2 in both AR and HR multilayers, HR's of Sc2O3/SiO2 and HfO2/SiO2, and Al-on-pyrex mirror; 9ns thresholds were between 0.2 to 5.6 J/sq cm. When these data were compared with a wide range of other results - for wavelengths from 0.25 to 10.6 microns and pulselengths down to 4ps - a remarkably consistent picture emerged. Damage thresholds, on average, increase approximately as the cube-root of pulselength from picoseconds to nearly a microsecond, and do so regardless of wavelength or material under test.

  7. Disrupted Sleep: From Molecules to Cognition

    OpenAIRE

    Someren, E.J.W.; Cirelli, C.; Dijk, D.-J.; Van Cauter, E; Schwartz, Sophie; Chee, M. W. L.

    2015-01-01

    Although the functions of sleep remain to be fully elucidated, it is clear that there are far-reaching effects of its disruption, whether by curtailment for a single night, by a few hours each night over a long period, or by disruption in sleep continuity. Epidemiological and experimental studies of these different forms of sleep disruption show deranged physiology from subcellular levels to complex affective behavior. In keeping with the multifaceted influence of sleep on health and well-bei...

  8. Disrupted Sleep: From Molecules to Cognition

    OpenAIRE

    Van Someren, Eus J. W.; Cirelli, Chiara; Dijk, Derk-Jan; Van Cauter, Eve; Schwartz, Sophie; Chee, Michael W. L.

    2015-01-01

    UNLABELLED: Although the functions of sleep remain to be fully elucidated, it is clear that there are far-reaching effects of its disruption, whether by curtailment for a single night, by a few hours each night over a long period, or by disruption in sleep continuity. Epidemiological and experimental studies of these different forms of sleep disruption show deranged physiology from subcellular levels to complex affective behavior. In keeping with the multifaceted influence of sleep on health ...

  9. Multistage Logistic Network Optimization under Disruption Risk

    OpenAIRE

    Rusman, Muhammad

    2013-01-01

    Getting over disruptions risk has been a challenging issue for many companies under the globalization that will link to potential external source such as demand uncertainties, natural disasters, and terrorist attacks. The disruption is an unexpected event that disturbs normal flows of products and materials within a supply chain. The disruption at one members of supply chain will propagate the offers and finally affect significant impacts on the entire chain. If we look back...

  10. Towards a Framework of Digital Platform Disruption

    OpenAIRE

    Kazan, Erol; Tan, Chee-Wee; Lim, Eric T. K.

    2014-01-01

    Digital platforms are disruptive information technology (IT) artifacts that erode conventional business logic associated with traditional market structures. This paper presents a framework for examining the disruptive potential of digital platforms whereby we postulate that the strategic interplay of governance regimes and platform layers is deterministic of whether disruptive derivatives are permitted to flourish. This framework has been employed in a comparative case study betwe...

  11. Disruption management in passenger railway transportation.

    OpenAIRE

    Jespersen-Groth, J.; Potthoff, Daniel; Clausen, J.; Huisman, Dennis; Kroon, Leo; Maróti, Gábor; Nielsen, M.N.

    2007-01-01

    textabstractThis paper deals with disruption management in passenger railway transportation. In the disruption management process, many actors belonging to different organizations play a role. In this paper we therefore describe the process itself and the roles of the different actors. Furthermore, we discuss the three main subproblems in railway disruption management: timetable adjustment, and rolling stock and crew re-scheduling. Next to a general description of these problems, we give an o...

  12. Household catastrophic healthcare expenditure and impoverishment due to rotavirus gastroenteritis requiring hospitalization in Malaysia.

    Directory of Open Access Journals (Sweden)

    Tharani Loganathan

    Full Text Available While healthcare costs for rotavirus gastroenteritis requiring hospitalization may be burdensome on households in Malaysia, exploration on the distribution and catastrophic impact of these expenses on households are lacking.We assessed the economic burden, levels and distribution of catastrophic healthcare expenditure, the poverty impact on households and inequities related to healthcare payments for acute gastroenteritis requiring hospitalization in Malaysia.A two-year prospective, hospital-based study was conducted from 2008 to 2010 in an urban (Kuala Lumpur and rural (Kuala Terengganu setting in Malaysia. All children under the age of 5 years admitted for acute gastroenteritis were included. Patients were screened for rotavirus and information on healthcare expenditure was obtained.Of the 658 stool samples collected at both centers, 248 (38% were positive for rotavirus. Direct and indirect costs incurred were significantly higher in Kuala Lumpur compared with Kuala Terengganu (US$222 Vs. US$45; p<0.001. The mean direct and indirect costs for rotavirus gastroenteritis consisted 20% of monthly household income in Kuala Lumpur, as compared with only 5% in Kuala Terengganu. Direct medical costs paid out-of-pocket caused 141 (33% households in Kuala Lumpur to experience catastrophic expenditure and 11 (3% households to incur poverty. However in Kuala Terengganu, only one household (0.5% experienced catastrophic healthcare expenditure and none were impoverished. The lowest income quintile in Kuala Lumpur was more likely to experience catastrophic payments compared to the highest quintile (87% vs 8%. The concentration index for out-of-pocket healthcare payments was closer to zero at Kuala Lumpur (0.03 than at Kuala Terengganu (0.24.While urban households were wealthier, healthcare expenditure due to gastroenteritis had more catastrophic and poverty impact on the urban poor. Universal rotavirus vaccination would reduce both disease burden and health

  13. Current disruption in toroidal devices

    International Nuclear Information System (INIS)

    Attempts at raising the density or the plasma current in a tokamak above certain critical values generally result in termination of the discharge by a disruption. This sudden end of the plasma current and plasma confinement is accompanied by large induced voltages and currents in the outer structures which, in large tokamaks, can only be handled with considerable effort, and which will probably only be tolerable in reactors as rare accidents. Because of its crucial importance for the construction and operation of tokamaks, this phenomenon and its theoretical interpretation were the subject of a three-day symposium organized by the International Atomic Energy Agency and Max-Planck-Institut fuer Plasmaphysik at Garching from February 14 to 16. (orig./HT)

  14. Disrupting Entanglement of Black Holes

    CERN Document Server

    Leichenauer, Stefan

    2014-01-01

    We study entanglement in thermofield double states of strongly coupled CFTs by analyzing two-sided Reissner-Nordstrom solutions in AdS. The central object of study is the mutual information between a pair of regions, one on each asymptotic boundary of the black hole. For large regions the mutual information is positive and for small ones it vanishes; we compute the critical length scale, which goes to infinity for extremal black holes, of the transition. We also generalize the butterfly effect of Shenker and Stanford to a wide class of charged black holes, showing that mutual information is disrupted upon perturbing the system and waiting for a time of order $\\log E/\\delta E$ in units of the temperature. We conjecture that the parametric form of this timescale is universal.

  15. Traffic disruption and recovery in road networks

    Science.gov (United States)

    Zhang, Lele; de Gier, Jan; Garoni, Timothy M.

    2014-05-01

    We study the impact of disruptions on road networks, and the recovery process after the disruption is removed from the system. Such disruptions could be caused by vehicle breakdown or illegal parking. We analyze the transient behavior using domain wall theory, and compare these predictions with simulations of a stochastic cellular automaton model. We find that the domain wall model can reproduce the time evolution of flow and density during the disruption and the recovery processes, for both one-dimensional systems and two-dimensional networks.

  16. Requiem for analytical psychology: a reflection on Jung's (anti)catastrophic psychology.

    Science.gov (United States)

    Barreto, Marco Heleno

    2014-02-01

    This article is an interpretation of analytical psychology in the light of the catastrophic vision and dreams that Jung had in 1913 and 1914. It is shown how the guiding spirit of Jung's psychological project is to be found in that psychic material. Then it is proposed that the completion of the symbolic catastrophe displayed in Jung's last vision (1961) points to the end of the psychological foundations upon which analytical psychology is built, and thus to its cultural obsolescence, extensive to any psychology grounded in Jung's notion of 'soul'. PMID:24467353

  17. Roll stability catastrophe mechanism of a flooded ship on regular sea waves

    International Nuclear Information System (INIS)

    Based on a typical one-free-degree ship roll motion equation, the cusp catastrophe model is built including the bifurcation set equation, splitting factor ‘u’ and regular factor ‘v’, where both ‘u’ and ‘v’ are further expressed with typical flooded ship parameters. Then, the roll catastrophe mechanism is analyzed mainly by means ‘u’, under the given parameters of a typical trawler boat. The aim of this research is to reveal the mutagenic mechanism of the roll stability and provide a reference for improving ship roll stability. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  18. Catastrophes and Conservation: Lessons from Sea Otters and the Exxon Valdez

    Directory of Open Access Journals (Sweden)

    Estes J.A.

    1992-02-01

    Full Text Available The Exxon Valdez spill is broadly perceived as an environmental catastrophe. However, expected catastrophic declines in the region's sea otter population cannot be demonstrated, not because they didn't occur but because the necessary information is lacking. Furthermore, efforts to rehabilitate oiled sea otters following the spill were extremely expensive and ineffective. Some improvements are possible with better planning. However, post-spill capture and rehabilitation probably can not be used to substantially reduce sea otter losses from future spills, and the use of such measures to conserve populations is unrealistic.

  19. Pain catastrophizing as a risk factor for chronic pain after total knee arthroplasty: a systematic review

    Directory of Open Access Journals (Sweden)

    Burns LC

    2015-01-01

    Full Text Available Lindsay C Burns,1–3 Sarah E Ritvo,1 Meaghan K Ferguson,1 Hance Clarke,3–5 Ze’ev Seltzer,3,5 Joel Katz1,3–5 1Department of Psychology, York University, Toronto, ON, Canada; 2Arthritis Research Centre of Canada, Vancouver, BC, Canada; 3Department of Anesthesia and Pain Management, Toronto General Hospital, Toronto, ON, Canada; 4Department of Anesthesia, University of Toronto, Toronto, ON, Canada; 5Centre for the Study of Pain, Faculties of Dentistry and Medicine, University of Toronto, Toronto, ON, Canada Background: Total knee arthroplasty (TKA is a common and costly surgical procedure. Despite high success rates, many TKA patients develop chronic pain in the months and years following surgery, constituting a public health burden. Pain catastrophizing is a construct that reflects anxious preoccupation with pain, inability to inhibit pain-related fears, amplification of the significance of pain vis-à-vis health implications, and a sense of helplessness regarding pain. Recent research suggests that it may be an important risk factor for untoward TKA outcomes. To clarify this impact, we systematically reviewed the literature to date on pain catastrophizing as a prospective predictor of chronic pain following TKA. Methods: We searched MEDLINE, EMBASE, and PsycINFO databases to identify articles related to pain catastrophizing, TKA, risk models, and chronic pain. We reviewed titles and abstracts to identify original research articles that met our specified inclusion criteria. Included articles were then rated for methodological quality. including methodological quality. Due to heterogeneity in follow-up, analyses, and outcomes reported across studies, a quantitative meta-analysis could not be performed. Results: We identified six prospective longitudinal studies with small-to-mid-sized samples that met the inclusion criteria. Despite considerable variability in reported pain outcomes, pain catastrophizing was identified as a significant

  20. Nonlinear analysis of the cooperation of strategic alliances through stochastic catastrophe theory

    Science.gov (United States)

    Xu, Yan; Hu, Bin; Wu, Jiang; Zhang, Jianhua

    2014-04-01

    The excitation intervention of strategic alliance may change with the changes in the parameters of circumstance (e.g., external alliance tasks). As a result, the stable cooperation between members may suffer a complete unplanned betrayal at last. However, current perspectives on strategic alliances cannot adequately explain this transition mechanism. This study is a first attempt to analyze this nonlinear phenomenon through stochastic catastrophe theory (SCT). A stochastic dynamics model is constructed based on the cooperation of strategic alliance from the perspective of evolutionary game theory. SCT explains the discontinuous changes caused by the changes in environmental parameters. Theoretically, we identify conditions where catastrophe can occur in the cooperation of alliance members.

  1. Model and algorithm for optimization of rescue center location of emergent catastrophe

    Institute of Scientific and Technical Information of China (English)

    WANG Ding-wei; ZHANG Guo-xiang

    2006-01-01

    The location of rescue centers is a key problem in optimal resource allocation and logistics in emergency response.We propose a mathematical model for rescue center location with the considerations of emergency occurrence probability,catastrophe diffusion function and rescue function.Because the catastrophe diffusion and rescue functions are both nonlinear and time-variable,it cannot be solved by common mathematical programming methods.We develop a heuristic embedded genetic algorithm for the special model solution.The computation based on a large number of examples with practical data has shown us satisfactory results.

  2. Imaging findings in the rare catastrophic variant of the primary antiphospholipid syndrome

    International Nuclear Information System (INIS)

    We report imaging findings in a case of the rare catastrophic variant of antiphospholipid syndrome (CAPS) characterized by widespread microvascular occlusions, which may lead to multiple organ failure. We present a case of a 66-year-old woman with bone marrow necrosis, acute acalculous cholecystitis (AAC), focal liver necrosis, subtle patchy splenic infarctions, and bilateral adrenal infarction. The demonstration of multiple microvascular organ involvement (three or more) is crucial for the diagnosis of the catastrophic variant of APS. This can be performed radiologically intra-vitam. Imaging can even reveal subclinical microinfarctions, which are often only diagnosed at autopsy. (orig.)

  3. Imaging findings in the rare catastrophic variant of the primary antiphospholipid syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Thuerl, Christina; Altehoefer, Carsten; Laubenberger, Joerg [Freiburg Univ. (Germany). Abt. Radiologie; Spyridonidis, Alexandros [Freiburg Univ. (DE). Abt. Innere Medizin 1 (Haematologie und Onkologie)

    2002-03-01

    We report imaging findings in a case of the rare catastrophic variant of antiphospholipid syndrome (CAPS) characterized by widespread microvascular occlusions, which may lead to multiple organ failure. We present a case of a 66-year-old woman with bone marrow necrosis, acute acalculous cholecystitis (AAC), focal liver necrosis, subtle patchy splenic infarctions, and bilateral adrenal infarction. The demonstration of multiple microvascular organ involvement (three or more) is crucial for the diagnosis of the catastrophic variant of APS. This can be performed radiologically intra-vitam. Imaging can even reveal subclinical microinfarctions, which are often only diagnosed at autopsy. (orig.)

  4. Disrupted Brain Functional Network Architecture in Chronic Tinnitus Patients

    Science.gov (United States)

    Chen, Yu-Chen; Feng, Yuan; Xu, Jin-Jing; Mao, Cun-Nan; Xia, Wenqing; Ren, Jun; Yin, Xindao

    2016-01-01

    Purpose: Resting-state functional magnetic resonance imaging (fMRI) studies have demonstrated the disruptions of multiple brain networks in tinnitus patients. Nonetheless, several studies found no differences in network processing between tinnitus patients and healthy controls (HCs). Its neural bases are poorly understood. To identify aberrant brain network architecture involved in chronic tinnitus, we compared the resting-state fMRI (rs-fMRI) patterns of tinnitus patients and HCs. Materials and Methods: Chronic tinnitus patients (n = 24) with normal hearing thresholds and age-, sex-, education- and hearing threshold-matched HCs (n = 22) participated in the current study and underwent the rs-fMRI scanning. We used degree centrality (DC) to investigate functional connectivity (FC) strength of the whole-brain network and Granger causality to analyze effective connectivity in order to explore directional aspects involved in tinnitus. Results: Compared to HCs, we found significantly increased network centrality in bilateral superior frontal gyrus (SFG). Unidirectionally, the left SFG revealed increased effective connectivity to the left middle orbitofrontal cortex (OFC), left posterior lobe of cerebellum (PLC), left postcentral gyrus, and right middle occipital gyrus (MOG) while the right SFG exhibited enhanced effective connectivity to the right supplementary motor area (SMA). In addition, the effective connectivity from the bilateral SFG to the OFC and SMA showed positive correlations with tinnitus distress. Conclusions: Rs-fMRI provides a new and novel method for identifying aberrant brain network architecture. Chronic tinnitus patients have disrupted FC strength and causal connectivity mostly in non-auditory regions, especially the prefrontal cortex (PFC). The current findings will provide a new perspective for understanding the neuropathophysiological mechanisms in chronic tinnitus. PMID:27458377

  5. Forecasting scenarios of collision catastrophes produced by celestial body falls

    Science.gov (United States)

    Shor, V.; Kochetova, O.; Chernetenko, Y.; Zheleznov, N.; Deryugin, V.; Zaitsev, A.

    2014-07-01

    The subject under discussion arose in the course of developing a computer program, which gives the possibility for numerical and graphical modeling of the scenarios of catastrophes caused by collisions of cosmic bodies with the Earth. It is expected that this program can be used for computer-assisted training of the personnel of units of the Ministry for Emergency Situations in the case of a situation caused by the fall of a celestial body on the Earth. Also, it is anticipated that the program can be used in real situations when a dangerous body is discovered on an orbit leading to an imminent collision with the Earth. From the scientific point of view, both variants of use require solving of analogous tasks. In what follows, we discuss both variants. 1. The computation of the circumstances for a fall on the Earth (or approach within short distance) of a real body begins with the determination of its orbit from the observations available using the least-squares method. The mean square error of the representation of the observations on the base of the initial values of the coordinates and the velocities is computed, as well as their covariance matrix. Then, the trajectory of the body's motion is followed by numerical integration starting from the osculating epoch to the collision with the Earth or to its flyby. The computer program takes into account the various cases: at the initial moment, the body can move away from or approach the Earth, it can be outside the sphere of action or inside it. At the moment, when the body enters the sphere of action, the coordinates of the center of the dispersion ellipse on the target plane are computed as well as the dimensions of its axes. Using these data, the probability of collision with the Earth is calculated. Then, the point of penetration of the body into the Earth's atmosphere at a given height above the level of the Earth geoid is determined. In case the body is passing by the Earth, the minimum distance of the body from

  6. Improving SUSY Spectrum Determinations at the LHC with Wedgebox and Hidden Threshold Techniques

    CERN Document Server

    Bisset, M; Lü, R

    2008-01-01

    The LHC has the potential not only to discover supersymmetry (SUSY), but also to permit fairly precise measurements of at least a portion of the sparticle spectrum. Proposed mass reconstruction methods rely upon either inverting invariant mass endpoint expressions or upon solving systems of mass-shell equations. These methodologies suffer from the weakness that one certain specific sparticle decay chain is assumed to account for all the events in the sample.Taking two examples of techniques utilizing mass-shell equations, it is found that also applying wedgebox and hidden threshold (HT) techniques allows for the isolation of a purer event sample, thus avoiding errors, possibly catastrophic, due to mistaken assumptions about the decay chains involved and simultaneously improving accuracy. What is innovative is using endpoint measurements (with wedgebox and HT techniques) to obtain a more homogeneous, well-understood sample set rather than just using said endpoints to constrain the values of the masses (here fo...

  7. Dyadic analysis of child and parent trait and state pain catastrophizing in the process of children's pain communication.

    Science.gov (United States)

    Birnie, Kathryn A; Chambers, Christine T; Chorney, Jill; Fernandez, Conrad V; McGrath, Patrick J

    2016-04-01

    When explored separately, child and parent catastrophic thoughts about child pain show robust negative relations with child pain. The objective of this study was to conduct a dyadic analysis to elucidate intrapersonal and interpersonal influences of child and parent pain catastrophizing on aspects of pain communication, including observed behaviours and perceptions of child pain. A community sample of 171 dyads including children aged 8 to 12 years (89 girls) and parents (135 mothers) rated pain catastrophizing (trait and state versions) and child pain intensity and unpleasantness following a cold pressor task. Child pain tolerance was also assessed. Parent-child interactions during the cold pressor task were coded for parent attending, nonattending, and other talk, and child symptom complaints and other talk. Data were analyzed using the actor-partner interdependence model and hierarchical multiple regressions. Children reporting higher state pain catastrophizing had greater symptom complaints regardless of level of parent state pain catastrophizing. Children reporting low state pain catastrophizing had similar high levels of symptom complaints, but only when parents reported high state pain catastrophizing. Higher child and parent state and/or trait pain catastrophizing predicted their own ratings of higher child pain intensity and unpleasantness, with child state pain catastrophizing additionally predicting parent ratings. Higher pain tolerance was predicted by older child age and lower child state pain catastrophizing. These newly identified interpersonal effects highlight the relevance of the social context to children's pain expressions and parent perceptions of child pain. Both child and parent pain catastrophizing warrant consideration when managing child pain. PMID:26713422

  8. Numerical Simulations of Collisional Disruption of Rotating Gravitational Aggregates: Dependence on Material Properties

    CERN Document Server

    Ballouz, Ronald-Louis; Michel, Patrick; Schwartz, Stephen R; Yu, Yang

    2014-01-01

    Our knowledge of the strengths of small bodies in the Solar System is limited by our poor understanding of their internal structures, and this, in turn, clouds our understanding of the formation and evolution of these bodies. Observations of the rotational states of asteroids whose diameters are larger than a few hundreds of meters have revealed that they are dominated by gravity and that most are unlikely to be monoliths; however, there is a wide range of plausible internal structures. Numerical and analytical studies of shape and spin limits of gravitational aggregates and their collisional evolution show a strong dependence on shear strength. In order to study this effect, we carry out a systematic exploration of the dependence of collision outcomes on dissipation and friction parameters of the material components making up the bodies. We simulate the catastrophic disruption (leading to the largest remnant retaining 50% of the original mass) of km-size asteroids modeled as gravitational aggregates using pk...

  9. Optimal thresholds for the estimation of area rain-rate moments by the threshold method

    Science.gov (United States)

    Short, David A.; Shimizu, Kunio; Kedem, Benjamin

    1993-01-01

    Optimization of the threshold method, achieved by determination of the threshold that maximizes the correlation between an area-average rain-rate moment and the area coverage of rain rates exceeding the threshold, is demonstrated empirically and theoretically. Empirical results for a sequence of GATE radar snapshots show optimal thresholds of 5 and 27 mm/h for the first and second moments, respectively. Theoretical optimization of the threshold method by the maximum-likelihood approach of Kedem and Pavlopoulos (1991) predicts optimal thresholds near 5 and 26 mm/h for lognormally distributed rain rates with GATE-like parameters. The agreement between theory and observations suggests that the optimal threshold can be understood as arising due to sampling variations, from snapshot to snapshot, of a parent rain-rate distribution. Optimal thresholds for gamma and inverse Gaussian distributions are also derived and compared.

  10. On the nullification of threshold amplitudes

    OpenAIRE

    Gonera, Joanna

    2002-01-01

    The nullification of threshold amplitudes is considered within the conventional framework of quantum field theory. The relevant Ward identities for the reduced theory are derived both on path-integral and diagrammatic levels. They are then used to prove the vanishing of tree-graph threshold amplitudes.

  11. Threshold Effects in Coral Reef Fisheries

    OpenAIRE

    Crépin, Anne Sophie

    2003-01-01

    Coral reefs may naturally flip between coral-dominated and algae-dominated states, when species' stocks trespass some threshold levels. This essay uses a stylized model of a coral reef to show how fishing may induce flips towards more algae-dominated states. Threshold effects have consequences for fisheries management, which are analyzed for open access fisheries and sole ownership.

  12. Threshold Concepts, Systems and Learning for Sustainability

    Science.gov (United States)

    Sandri, Orana Jade

    2013-01-01

    This paper presents a framework for understanding the role that systems theory might play in education for sustainability (EfS). It offers a sketch and critique of Land and Meyer's notion of a "threshold concept", to argue that seeing systems as a threshold concept for sustainability is useful for understanding the processes of…

  13. Intelligence and Creativity: Over the Threshold Together?

    Science.gov (United States)

    Welter, Marisete Maria; Jaarsveld, Saskia; van Leeuwen, Cees; Lachmann, Thomas

    2016-01-01

    Threshold theory predicts a positive correlation between IQ and creativity scores up to an IQ level of 120 and no correlation above this threshold. Primary school children were tested at beginning (N = 98) and ending (N = 70) of the school year. Participants performed the standard progressive matrices (SPM) and the Test of Creative…

  14. Applying Threshold Concepts to Finance Education

    Science.gov (United States)

    Hoadley, Susan; Wood, Leigh N.; Tickle, Leonie; Kyng, Tim

    2016-01-01

    Purpose: The purpose of this paper is to investigate and identify threshold concepts that are the essential conceptual content of finance programmes. Design/Methodology/Approach: Conducted in three stages with finance academics and students, the study uses threshold concepts as both a theoretical framework and a research methodology. Findings: The…

  15. Detectability thresholds of general modular graphs

    CERN Document Server

    Kawamoto, Tatsuro

    2016-01-01

    We investigate the detectability thresholds of various modular structures in the stochastic block model. Our analysis reveals how the detectability threshold is related to the details of the modular pattern, including the hierarchy of the clusters. We show that certain planted structures are impossible to infer regardless of their fuzziness.

  16. Thresholding magnetic resonance images of human brain

    Institute of Scientific and Technical Information of China (English)

    Qing-mao HU; Wieslaw L NOWINSKI

    2005-01-01

    In this paper, methods are proposed and validated to determine low and high thresholds to segment out gray matter and white matter for MR images of different pulse sequences of human brain. First, a two-dimensional reference image is determined to represent the intensity characteristics of the original three-dimensional data. Then a region of interest of the reference image is determined where brain tissues are present. The non-supervised fuzzy c-means clustering is employed to determine: the threshold for obtaining head mask, the low threshold for T2-weighted and PD-weighted images, and the high threshold for T1-weighted, SPGR and FLAIR images. Supervised range-constrained thresholding is employed to determine the low threshold for T1-weighted, SPGR and FLAIR images. Thresholding based on pairs of boundary pixels is proposed to determine the high threshold for T2- and PD-weighted images. Quantification against public data sets with various noise and inhomogeneity levels shows that the proposed methods can yield segmentation robust to noise and intensity inhomogeneity. Qualitatively the proposed methods work well with real clinical data.

  17. Voting on Thresholds for Public Goods

    DEFF Research Database (Denmark)

    Rauchdobler, Julian; Sausgruber, Rupert; Tyran, Jean-Robert

    2010-01-01

    Introducing a threshold in the sense of a minimal project size transforms a public-good game with an inefficient equilibrium into a coordination game with a set of Pareto-superior equilibria. Thresholds may therefore improve efficiency in the voluntary provision of public goods. In our one...

  18. Provably secure robust threshold partial blind signature

    Institute of Scientific and Technical Information of China (English)

    CAO Zhenfu; ZHU Haojin; LU Rongxing

    2006-01-01

    Threshold digital signature and blind signature are playing important roles in cryptography as well as in practical applications such as e-cash and e-voting systems.Over the past few years, many cryptographic researchers have made considerable headway in this field. However, to our knowledge, most of existing threshold blind signature schemes are based on the discrete logarithm problem. In this paper, we propose a new robust threshold partial blind signature scheme based on improved RSA cryptosystem.This scheme is the first threshold partial blind signature scheme based on factoring, and the robustness of threshold partial blind signature is also introduced. Moreover, in practical application, the proposed scheme will be especially suitable for blind signature-based voting systems with multiple administrators and secure electronic cash systems to prevent their abuse.

  19. Summary of DOE threshold limits efforts

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) has been developing the concept of threshold quantities for use in determining which waste materials may be disposed of as nonradioactive waste in DOE sanitary landfills. Waste above a threshold level could be managed as radioactive or mixed waste (if hazardous chemicals are present); waste below this level would be handled as sanitary waste. After extensive review of a draft threshold guidance document in 1985, a second draft threshold background document was produced in March 1986. The second draft included a preliminary cost-benefit analysis and quality assurance considerations. The review of the second draft has been completed. Final changes to be incorporated include an in-depth cost-benefit analysis of two example sites and recommendations of how to further pursue (i.e. employ) the concept of threshold quantities within the DOE. 3 references

  20. Scaled biotic disruption during early Eocene global warming events

    Directory of Open Access Journals (Sweden)

    S. J. Gibbs

    2012-11-01

    Full Text Available Late Paleocene and early Eocene hyperthermals are transient warming events associated with massive perturbations of the global carbon cycle, and are considered partial analogues for current anthropogenic climate change. Because the magnitude of carbon release varied between the events, they are natural experiments ideal for exploring the relationship between carbon cycle perturbations, climate change and biotic response. Here we quantify marine biotic variability through three million years of the early Eocene that include five hyperthermals, utilizing a method that allows us to integrate the records of different plankton groups through scenarios ranging from background to major extinction events. Our long time-series calcareous nannoplankton record indicates a scaling of biotic disruption to climate change associated with the amount of carbon released during the various hyperthermals. Critically, only the three largest hyperthermals, the Paleocene–Eocene Thermal Maximum (PETM, Eocene Thermal Maximum 2 (ETM2 and the I1 event, show above-background variance, suggesting that the magnitude of carbon input and associated climate change needs to surpass a threshold value to cause significant biotic disruption.