WorldWideScience

Sample records for model paradox mace4

  1. Paradox of integration -- a computational model

    CERN Document Server

    Krawczyk, Malgorzata J

    2016-01-01

    The paradoxical aspect of integration of a social group has been highlighted by Peter Blau (Exchange and Power in Social Life, Wiley and Sons, 1964). During the integration process, the group members simultaneously compete for social status and play the role of the audience. Here we show that when the competition prevails over the desire of approval, a sharp transition breaks all friendly relations. However, as was described by Blau, people with high status are inclined to bother more with acceptance of others; this is achieved by praising others and revealing her/his own weak points. In our model, this action smooths the transition and improves interpersonal relations.

  2. Paradox of integration-A computational model

    Science.gov (United States)

    Krawczyk, Małgorzata J.; Kułakowski, Krzysztof

    2017-02-01

    The paradoxical aspect of integration of a social group has been highlighted by Blau (1964). During the integration process, the group members simultaneously compete for social status and play the role of the audience. Here we show that when the competition prevails over the desire of approval, a sharp transition breaks all friendly relations. However, as was described by Blau, people with high status are inclined to bother more with acceptance of others; this is achieved by praising others and revealing her/his own weak points. In our model, this action smooths the transition and improves interpersonal relations.

  3. A Quantum Model for the Ellsberg and Machina Paradoxes

    CERN Document Server

    Aerts, Diederik; Tapia, Jocelyn

    2012-01-01

    The Ellsberg and Machina paradoxes reveal that expected utility theory is problematical when real subjects take decisions under uncertainty. Suitable generalizations of expected utility exist which attempt to solve the Ellsberg paradox, but none of them provides a satisfactory solution of the Machina paradox. In this paper we elaborate a quantum model in Hilbert space describing the Ellsberg situation and also the Machina situation, and show that we can model the specific aspect of the Machina situation that is unable to be modeled within the existing generalizations of expected utility.

  4. MODELING PARADOXES IN NOVICE AND EXPERT DESIGN

    DEFF Research Database (Denmark)

    Dorst, Kees; Hansen, Claus Thorp

    2011-01-01

    In their ICED09 paper ‘Problem formulation as a discursive activity’, the authors have used an extensive educational case study to explore a framework for describing design as a discursive activity, centered around the paradoxical nature of the problem situation. The ‘working definition’ for para...... at play in a design situation, and extract themes that can lead to reformulation of the problem as well as the creation of innovative solutions. This behaviour is compared to the ways of working of novice designers (students) in the original case study....

  5. A PARADOX OF TRANSIENT EKMAN DRIFT MODEL AND ITS EXPLAINATION

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In view of the fact that the simple analytic model is important both in acquiring the dynamic rule of Ocean and in understanding its mechanical essence, a unified solution of transient Ekman drift model encompassing the Fredholm’s solution with constant wind and the hidaka, Nomitsu, and Defant’s solution with unsteady wind is provided, and the paradox that it is uncertain if the solution satisfies the boundary condition is pointed out and explained. The present study shows that a simply mathematical treatment is able to remove this paradox, hoping to call for the mathematicians’ notice.

  6. A Contextual Risk Model for the Ellsberg Paradox

    CERN Document Server

    Aerts, Diederik

    2011-01-01

    The Allais and Ellsberg paradoxes show that the expected utility hypothesis and Savage's Sure-Thing Principle are violated in real life decisions. The popular explanation in terms of 'ambiguity aversion' is not completely accepted. On the other hand, we have recently introduced a notion of 'contextual risk' to mathematically capture what is known as 'ambiguity' in the economics literature. Situations in which contextual risk occurs cannot be modeled by Kolmogorovian classical probabilistic structures, but a non-Kolmogorovian framework with a quantum-like structure is needed. We prove in this paper that the contextual risk approach can be applied to the Ellsberg paradox, and elaborate a 'sphere model' within our 'hidden measurement formalism' which reveals that it is the overall conceptual landscape that is responsible of the disagreement between actual human decisions and the predictions of expected utility theory, which generates the paradox. This result points to the presence of a 'quantum conceptual layer'...

  7. Model selection bias and Freedman's paradox

    Science.gov (United States)

    Lukacs, P.M.; Burnham, K.P.; Anderson, D.R.

    2010-01-01

    In situations where limited knowledge of a system exists and the ratio of data points to variables is small, variable selection methods can often be misleading. Freedman (Am Stat 37:152-155, 1983) demonstrated how common it is to select completely unrelated variables as highly "significant" when the number of data points is similar in magnitude to the number of variables. A new type of model averaging estimator based on model selection with Akaike's AIC is used with linear regression to investigate the problems of likely inclusion of spurious effects and model selection bias, the bias introduced while using the data to select a single seemingly "best" model from a (often large) set of models employing many predictor variables. The new model averaging estimator helps reduce these problems and provides confidence interval coverage at the nominal level while traditional stepwise selection has poor inferential properties. ?? The Institute of Statistical Mathematics, Tokyo 2009.

  8. The hierarchical model of stem cell genesis explains the man mouse paradox, Peto's paradox, the red cell paradox and Wright's enigma.

    Science.gov (United States)

    Morris, James A

    2014-12-01

    The central dogma of carcinogenesis is that deleterious mutations accumulate in regularly cycling stem cells and eventually one of the cells will acquire a specific set of mutations which leads to uncontrolled cell proliferation. Each mutation is rare and the specific set is extremely rare so that even though there are millions of stem cells in a small area of mucosa the specific set of mutations to initiate the process of malignancy will only arise in one stem cell at most; hence neoplasia is clonal. But this model predicts that men, who are 1000 times larger than mice and live 30 times as long, should have a vastly increased risk of cancer compared with mice, but they don't (man-mouse paradox). The model also predicts that the prevalence of cancer in men should rise as power function of age and mutagen dose, the former is correct but not the latter (Peto's paradox). Furthermore there are more mitotic divisions in red cell precursors than in all other stem cells combined and yet erythroleukaemia is rare (red cell paradox). The central dogma is also challenged by Wright's enigma; the observation that some gastro-intestinal neoplasms are polyclonal in origin. The problem with the central dogma is the concept of a regularly cycling stem cell. In fact it is possible to produce all the cells that arise in a human lifetime with fewer than 60 rounds of DNA replication separating the zygote from mature differentiated cells in extreme old age. This hierarchical model of stem cell genesis leads to a very low prevalence of cancer, unless the orderly progression of the hierarchy is disturbed by inflammation, ulceration or trauma. This model explains the paradoxes and Wright's enigma. It is suggested that the number of cell divisions that separate the zygote from stem cells is a key variable in carcinogenesis. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

  9. IMPACT MODEL RESOLUTION ON PAINLEV(E)'S PARADOX

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhen; CHEN Bin; LIU Caishan; JIN Hai

    2004-01-01

    Painlevé's paradox is one of the basic difficulties for solving LCP of dynamic systems subjected to unilateral constraints. A bi-nonlinear parameterized impact model, consistent with dynamic principles and experimental results, is established on the localized and quasi-static impact model theory. Numerical simulations are carried out on the dynamic motion of Painleve's example. The results confirm "impact without collision" in the inconsistent states of the system. A "critical normal force" which brings an important effect on the future movement of the system in the indeterminate states is found. After the motion pattern for the impact process is obtained from numerical results,a rule of the velocity's jump that incorporates the tangential impact process is deduced by using an approximate impulse theory and the coefficient of restitution defined by Stronge. The results of the jump rule are quite precise if the system rigidity is big enough.

  10. The Analysis of Braess’ Paradox and Robustness Based on Dynamic Traffic Assignment Models

    Directory of Open Access Journals (Sweden)

    Bai-Bai Fu

    2013-01-01

    Full Text Available The investigation of the paradox and robustness about the traffic network is an important branch of the traffic assignment. In this paper, Braess’ paradox and robustness of the dynamic traffic network are analyzed by the dynamic traffic assignment models. In addition, the relationship of total costs with different traffic assignment models is discussed. The results show that the paradox only occurs in certain range; the robustness of the network and the relationship of total traffic costs are changed as the traffic demand changes, which provides theoretical guidance for the urban transportation planning.

  11. Resolving the Paradoxes of Creativity: An Extended Phase Model

    Science.gov (United States)

    Cropley, Arthur; Cropley, David

    2008-01-01

    Many teachers are interested in fostering creativity, and there are good reasons for doing so. However, the question of how to do it is made difficult by the paradoxes of creativity: mutually contradictory findings that are, nonetheless, simultaneously true (e.g. convergent thinking hampers creativity but is also necessary for it). These paradoxes…

  12. Paradoxical pharmacology: turning our pharmacological models upside down.

    Science.gov (United States)

    Page, Clive

    2011-04-01

    Paradoxical pharmacology is a term first suggested by Richard Bond to refer to intriguing observations that chronic use of some drug types can have the opposite biological effect(s) to those seen following acute administration of the same drug. A good example of 'paradoxical pharmacology' is the research Richard has pioneered showing that whereas acute administration of β-blockers is contraindicated in the treatment of asthma, chronic use of certain β-blockers can have therapeutic benefit. It would appear that those β-blockers that can act as inverse agonists at the β2 receptor particularly show this paradoxical effect and the findings of Richard's research not only challenge the dogma of the treatment of asthma but also challenge many of the pharmacological principles of ligand/receptor interactions established by Sir James Black and others. In this paper, I discuss Richard's efforts to evaluate the chronic effects of β-blockers in the airways and how this research caught the imagination of Sir James Black.

  13. Modelling non-paradoxical loss of information in black hole evaporation

    CERN Document Server

    Modak, Sujoy K

    2016-01-01

    We give general overview of a novel approach, recently developed by us, to address the issue black hole information paradox. This alternative viewpoint is based on theories involving modifications of standard quantum theory, known as "spontaneous dynamical state reduction" or "wave-function collapse models" which were historically developed to overcome the notorious foundational problems of quantum mechanics known as the "measurement problem". We show that these proposals, when appropriately adapted and refined for this context, provide a self-consistent picture where loss of information in the evaporation of black holes is no longer paradoxical.

  14. University-Community Partnership Models: Employing Organizational Management Theories of Paradox and Strategic Contradiction

    Science.gov (United States)

    Bowers, Amanda M.

    2017-01-01

    University-Community (U-C) partnerships have the potential to respond to society's most pressing needs through engaged scholarship. Despite this promise, partnerships face paradoxical tensions and inherent contradictions that are often not fully addressed in U-C partnership models or frameworks, or in practice. This article seeks to explore the…

  15. A paradox in individual-based models of populations

    NARCIS (Netherlands)

    Van der Meer, J.

    2016-01-01

    The standard dynamic energy budget model is widely used to describe the physiology of individual animals. It assumes thatassimilation rate scales with body surface area, whereas maintenance rate scales with body volume. When the model is usedas the building block of a population model, only limited

  16. Paradoxes of time travel

    CERN Document Server

    Krasnikov, S V

    1997-01-01

    Paradoxes that can supposedly occur if a time machine is created are discussed. It is shown that the existence of trajectories of ``multiplicity zero'' (i.e. trajectories that describe a ball hitting its younger self so that the latter cannot fall into the time machine) is not paradoxical by itself. This {\\em apparent paradox} can be resolved (at least sometimes) without any harm to local physics or to the time machine. Also a simple model is adduced for which the absence of {\\em true} paradoxes caused by self-interaction is proved.

  17. On the paradoxical evolution of the number of photons in a new model of interpolating Hamiltonians

    CERN Document Server

    Valverde, C

    2016-01-01

    We introduce a new Hamiltonian model which interpolates between the Jaynes-Cummings model and other types of such Hamiltonians. It works with two interpolating parameters, rather than one as traditional. Taking advantage of this greater degree of freedom, we can perform continuous interpolation between the various types of these Hamiltonians. As applications we discuss a paradox raised in literature and compare the time evolution of photon statistics obtained in the various interpolating models. The role played by the average excitation in these comparisons is also highlighted.

  18. Solutions to Peto's paradox revealed by mathematical modelling and cross-species cancer gene analysis.

    Science.gov (United States)

    Caulin, Aleah F; Graham, Trevor A; Wang, Li-San; Maley, Carlo C

    2015-07-19

    Whales have 1000-fold more cells than humans and mice have 1000-fold fewer; however, cancer risk across species does not increase with the number of somatic cells and the lifespan of the organism. This observation is known as Peto's paradox. How much would evolution have to change the parameters of somatic evolution in order to equalize the cancer risk between species that differ by orders of magnitude in size? Analysis of previously published models of colorectal cancer suggests that a two- to three-fold decrease in the mutation rate or stem cell division rate is enough to reduce a whale's cancer risk to that of a human. Similarly, the addition of one to two required tumour-suppressor gene mutations would also be sufficient. We surveyed mammalian genomes and did not find a positive correlation of tumour-suppressor genes with increasing body mass and longevity. However, we found evidence of the amplification of TP53 in elephants, MAL in horses and FBXO31 in microbats, which might explain Peto's paradox in those species. Exploring parameters that evolution may have fine-tuned in large, long-lived organisms will help guide future experiments to reveal the underlying biology responsible for Peto's paradox and guide cancer prevention in humans.

  19. Painlevé's paradox and dynamic jamming in simple models of passive dynamic walking

    Science.gov (United States)

    Or, Yizhar

    2014-02-01

    Painlevé's paradox occurs in the rigid-body dynamics of mechanical systems with frictional contacts at configurations where the instantaneous solution is either indeterminate or inconsistent. Dynamic jamming is a scenario where the solution starts with consistent slippage and then converges in finite time to a configuration of inconsistency, while the contact force grows unbounded. The goal of this paper is to demonstrate that these two phenomena are also relevant to the field of robotic walking, and can occur in two classical theoretical models of passive dynamic walking — the rimless wheel and the compass biped. These models typically assume sticking contact and ignore the possibility of foot slippage, an assumption which requires sufficiently large ground friction. Nevertheless, even for large friction, a perturbation that involves foot slippage can be kinematically enforced due to external forces, vibrations, or loose gravel on the surface. In this work, the rimless wheel and compass biped models are revisited, and it is shown that the periodic solutions under sticking contact can suffer from both Painlevé's paradox and dynamic jamming when given a perturbation of foot slippage. Thus, avoidance of these phenomena and analysis of orbital stability with respect to perturbations that include slippage are of crucial importance for robotic legged locomotion.

  20. Solutions to the faint young Sun paradox simulated by a general circulation model

    Science.gov (United States)

    Wolf, Eric Theodore

    The faint young Sun paradox has dominated our thinking regarding early climate. Geological evidence abounds for warm, possibly hot, seawater temperatures and the proliferation of early life during the Archean period of Earth's history (3.8-2.5 Ga). However the standard solar model indicates that the Sun was only 75 to 82 percent as bright as today, implying an apparent contradiction between warm surface temperatures and weak solar irradiance. Geological evidence also places constraints on the amount of atmospheric carbon dioxide present early in Earth's history. Over the past four decades there has been much debate amongst geological, planetary, and climate science communities regarding how to properly resolve the issue of the faint young Sun. Up until very recently, 1-dimensional radiative convective models were the standard tool for deep paleoclimate modeling studies. These studies have notably lacked the ability to treat clouds, surface ice, and meridional energy transport. However, advancements in computing technology now allow us to tackle the faint young Sun paradox using a three-dimensional climate model. Here we use a modified version of the Community Atmosphere Model version 3 from the National Center for Atmospheric Research to study early climate. We find that resolving the faint young Sun paradox becomes less problematic when viewing a full representation of the climate system. Modest amounts of carbon dioxide and methane can provide adequate warming for the Archean within given constraints. Cooler climates with large ice caps but temperate tropical regions can be supported with even less carbon dioxide. The incorporation of systematic climate system differences expected during the Archean, such as fewer cloud condensation nuclei, reduced land albedos, and increased atmospheric nitrogen, can provide additional non-greenhouse means of warming the early Earth. A warm Archean no longer appears at odds with a faint young Sun. Here, we will also discuss the

  1. The integrate model of emotion, thinking and self regulation: an application to the "paradox of aging".

    Science.gov (United States)

    Williams, Leanne M; Gatt, Justine M; Hatch, Ainslie; Palmer, Donna M; Nagy, Marie; Rennie, Christopher; Cooper, Nicholas J; Morris, Charlotte; Grieve, Stuart; Dobson-Stone, Carol; Schofield, Peter; Clark, C Richard; Gordon, Evian; Arns, Martijn; Paul, Robert H

    2008-09-01

    This study was undertaken using the INTEGRATE Model of brain organization, which is based on a temporal continuum of emotion, thinking and self regulation. In this model, the key organizing principle of self adaption is the motivation to minimize danger and maximize reward. This principle drives brain organization across a temporal continuum spanning milliseconds to seconds, minutes and hours. The INTEGRATE Model comprises three distinct processes across this continuum. Emotion is defined by automatic action tendencies triggered by signals that are significant due to their relevance to minimizing danger-maximizing reward (such as abrupt, high contrast stimuli). Thinking represents cognitive functions and feelings that rely on brain and body feedback emerging from around 200 ms post-stimulus onwards. Self regulation is the modulation of emotion, thinking and feeling over time, according to more abstract adaptions to minimize danger-maximize reward. Here, we examined the impact of dispositional factors, age and genetic variation, on this temporal continuum. Brain Resource methodology provided a standardized platform for acquiring genetic, brain and behavioral data in the same 1000 healthy subjects. Results showed a "paradox" of declining function in the "thinking" time scale over the lifespan (6 to 80+ years), but a corresponding preservation or even increase in automatic functions of "emotion" and "self regulation". This paradox was paralleled by a greater loss of grey matter in cortical association areas (assessed using MRI) over age, but a relative preservation of subcortical grey matter. Genetic polymorphisms associated with both healthy function and susceptibility to disorder (including the BDNFVal(66)Met, COMTVal(158/108)Met, MAOA and DRD4 tandem repeat and 5HTT-LPR polymorphisms) made specific contributions to emotion, thinking and self regulatory functions, which also varied according to age.

  2. The Dynamic Range Paradox: A Central Auditory Model of Intensity Change Detection

    Science.gov (United States)

    Simpson, Andrew J.R.; Reiss, Joshua D.

    2013-01-01

    In this paper we use empirical loudness modeling to explore a perceptual sub-category of the dynamic range problem of auditory neuroscience. Humans are able to reliably report perceived intensity (loudness), and discriminate fine intensity differences, over a very large dynamic range. It is usually assumed that loudness and intensity change detection operate upon the same neural signal, and that intensity change detection may be predicted from loudness data and vice versa. However, while loudness grows as intensity is increased, improvement in intensity discrimination performance does not follow the same trend and so dynamic range estimations of the underlying neural signal from loudness data contradict estimations based on intensity just-noticeable difference (JND) data. In order to account for this apparent paradox we draw on recent advances in auditory neuroscience. We test the hypothesis that a central model, featuring central adaptation to the mean loudness level and operating on the detection of maximum central-loudness rate of change, can account for the paradoxical data. We use numerical optimization to find adaptation parameters that fit data for continuous-pedestal intensity change detection over a wide dynamic range. The optimized model is tested on a selection of equivalent pseudo-continuous intensity change detection data. We also report a supplementary experiment which confirms the modeling assumption that the detection process may be modeled as rate-of-change. Data are obtained from a listening test (N = 10) using linearly ramped increment-decrement envelopes applied to pseudo-continuous noise with an overall level of 33 dB SPL. Increments with half-ramp durations between 5 and 50,000 ms are used. The intensity JND is shown to increase towards long duration ramps (p<10−6). From the modeling, the following central adaptation parameters are derived; central dynamic range of 0.215 sones, 95% central normalization, and a central loudness JND

  3. The dynamic range paradox: a central auditory model of intensity change detection.

    Directory of Open Access Journals (Sweden)

    Andrew J R Simpson

    Full Text Available In this paper we use empirical loudness modeling to explore a perceptual sub-category of the dynamic range problem of auditory neuroscience. Humans are able to reliably report perceived intensity (loudness, and discriminate fine intensity differences, over a very large dynamic range. It is usually assumed that loudness and intensity change detection operate upon the same neural signal, and that intensity change detection may be predicted from loudness data and vice versa. However, while loudness grows as intensity is increased, improvement in intensity discrimination performance does not follow the same trend and so dynamic range estimations of the underlying neural signal from loudness data contradict estimations based on intensity just-noticeable difference (JND data. In order to account for this apparent paradox we draw on recent advances in auditory neuroscience. We test the hypothesis that a central model, featuring central adaptation to the mean loudness level and operating on the detection of maximum central-loudness rate of change, can account for the paradoxical data. We use numerical optimization to find adaptation parameters that fit data for continuous-pedestal intensity change detection over a wide dynamic range. The optimized model is tested on a selection of equivalent pseudo-continuous intensity change detection data. We also report a supplementary experiment which confirms the modeling assumption that the detection process may be modeled as rate-of-change. Data are obtained from a listening test (N = 10 using linearly ramped increment-decrement envelopes applied to pseudo-continuous noise with an overall level of 33 dB SPL. Increments with half-ramp durations between 5 and 50,000 ms are used. The intensity JND is shown to increase towards long duration ramps (p<10(-6. From the modeling, the following central adaptation parameters are derived; central dynamic range of 0.215 sones, 95% central normalization, and a central

  4. Rupture mechanism and interface separation in foam rubber models of earthquakes: a possible solution to the heat flow paradox and the paradox of large overthrusts

    Science.gov (United States)

    Brune, James N.; Brown, Stephen; Johnson, Peggy A.

    1993-02-01

    Spontaneous stick-slip along the interface between stressed foam rubber blocks is a simple analog of earthquake rupture and stick-slip. Results from this model are used to elucidate the role of normal stress variations along the interface in the stick-slip process. Observations indicate significant normal interface vibrations and separation during slip, suggesting that dynamic changes in normal stress (rather than a drop in the coefficient of friction) may control stick-slip, as suggested, for example, by Tolstoi, Oden and Martins and Brune and co-workers. Observations of particle trajectories indicate that stick-slip shear motion is associated with various degrees of fault separation. For an asymmetric model, the motion is consistent with slipping motion of the type suggested by Schallamach and Price. For a symmetric model, the motion is similar to that suggested by Comninou and Dundurs. If interface waves of this type, involving separation during slip, occur in earthquakes, they may be a solution to the heat flow paradox, since a major part of the slip occurs during separation and during low normal stress. Thus frictional heat generation is reduced. Normal interface vibrations during stick-slip may explain the high corner frequency of P wave spectra and the generally high levels of P wave spectra beyond the corner frequency. Schallamach-Comninou type waves are consistent with the partial stress drop-abrupt locking-self healing models of Brune and Heaton.

  5. Solutions to Peto's paradox revealed by mathematical modelling and cross-species cancer gene analysis

    National Research Council Canada - National Science Library

    Caulin, Aleah F; Graham, Trevor A; Wang, Li-San; Maley, Carlo C

    2015-01-01

    .... This observation is known as Peto's paradox. How much would evolution have to change the parameters of somatic evolution in order to equalize the cancer risk between species that differ by orders of magnitude in size...

  6. Paradox of the drinking-straw model of the butterfly proboscis.

    Science.gov (United States)

    Tsai, Chen-Chih; Monaenkova, Daria; Beard, Charles E; Adler, Peter H; Kornev, Konstantin G

    2014-06-15

    Fluid-feeding Lepidoptera use an elongated proboscis, conventionally modeled as a drinking straw, to feed from pools and films of liquid. Using the monarch butterfly, Danaus plexippus (Linnaeus), we show that the inherent structural features of the lepidopteran proboscis contradict the basic assumptions of the drinking-straw model. By experimentally characterizing permeability and flow in the proboscis, we show that tapering of the food canal in the drinking region increases resistance, significantly hindering the flow of fluid. The calculated pressure differential required for a suction pump to support flow along the entire proboscis is greater than 1 atm (~101 kPa) when the butterfly feeds from a pool of liquid. We suggest that behavioral strategies employed by butterflies and moths can resolve this paradoxical pressure anomaly. Butterflies can alter the taper, the interlegular spacing and the terminal opening of the food canal, thereby controlling fluid entry and flow, by splaying the galeal tips apart, sliding the galeae along one another, pulsing hemolymph into each galeal lumen, and pressing the proboscis against a substrate. Thus, although physical construction of the proboscis limits its mechanical capabilities, its functionality can be modified and enhanced by behavioral strategies.

  7. Step out the Paradox of Livable City Studies:Conceptual Model and Path Choice

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Based on a comparative analysis on the concepts and standards of livable city in China and abroad,the paper creates a conceptual model and a fundamental formula for livable city development with economic development as the foundation,and the social and cultural conditions,the ecological status,and the city governance as three pillars,so as to provide a theoretical explanation for the two paradoxes of livable city.The paper suggests that China should choose Path C,which combines economic development with city livability.It also analyzes the development rules of livable city under Path C,and talks about the fundamental ideas of livable city construction under the current circumstances in China.In the end,the paper puts forward related planning strategies in terms of spatial structure,ecological environment,cultural construction,transportation system,and housing system,in order to establish a livable city development model that is suitable for China’s practical conditions.

  8. Simpson's Paradox, Lord's Paradox, and Suppression Effects are the same phenomenon – the reversal paradox

    Science.gov (United States)

    Tu, Yu-Kang; Gunnell, David; Gilthorpe, Mark S

    2008-01-01

    This article discusses three statistical paradoxes that pervade epidemiological research: Simpson's paradox, Lord's paradox, and suppression. These paradoxes have important implications for the interpretation of evidence from observational studies. This article uses hypothetical scenarios to illustrate how the three paradoxes are different manifestations of one phenomenon – the reversal paradox – depending on whether the outcome and explanatory variables are categorical, continuous or a combination of both; this renders the issues and remedies for any one to be similar for all three. Although the three statistical paradoxes occur in different types of variables, they share the same characteristic: the association between two variables can be reversed, diminished, or enhanced when another variable is statistically controlled for. Understanding the concepts and theory behind these paradoxes provides insights into some controversial or contradictory research findings. These paradoxes show that prior knowledge and underlying causal theory play an important role in the statistical modelling of epidemiological data, where incorrect use of statistical models might produce consistent, replicable, yet erroneous results. PMID:18211676

  9. Does experimental paradoxical sleep deprivation (EPSD) is an appropriate model for evaluation of cardiovascular complications of obstructive sleep apnea?

    Science.gov (United States)

    Joukar, Siyavash; Ghorbani-Shahrbabaki, Soodabe

    2016-05-01

    Some of the previous studies have used animal model of paradoxical sleep deprivation for investigation of sleep loss complications. The present study is designed to examine the effectiveness and reliability of this model for investigation and assessment of some cardiovascular complications of obstructive sleep apnea syndrome. The Wistar rat groups were divided into the control group, the Test48 and Test72 groups, who experienced paradoxical sleep deprivation for 48 and 72 h, and the Sham48 and Sham72 groups, who were exposed to environmental conditions same to test groups but without sleep deprivation, respectively. At the end of the experiment, blood pressure and heart rate variability were assessed. The results showed that 72 h rapid eye movements sleep deprivation significantly increased the systolic blood pressure compared to the control (p sleep deprivation may be a suitable model for induction and investigation of hemodynamic alterations which occurs in obstructive sleep apnea syndrome; however, it cannot be an alternative model to induce heart rate variability alterations similar to those reported in patient with obstructive sleep apnea.

  10. [Obesity paradox].

    Science.gov (United States)

    Aursulesei, Viviana; Cozma, A; Datcu, M D

    2009-01-01

    Obesity has reached global epidemic proportions and is associated with major cardiovascular diseases and reduced overall survival. This paper reviews the metabolic and vascular consequences of dysfunctional adipocytokines in obesity as well as the pathological effects on blood pressure, cardiovascular structure and function. Despite this adverse association, numerous studies have documented an obesity paradox in which overweight and obese population with established cardiovascular disease have a better prognosis. There are potential explanations offered by literature for these puzzling data. For obese hypertensive patients the paradox is possibly linked to the lower systemic vascular resistance and plasma renin activity. In heart failure the excess body weight may confer some protective effects on mortality, due to a more metabolic reserve, higher levels of arterial pressure compatible with higher doses of cardioprotective medications, and a specific neuroendocrine profile with lower levels of circulating natriuretic atrial peptides, attenuated sympathetic nervous system and renin-angiotensin responses. For coronary heart disease and peripheral arterial disease the mechanisms are still uncertain. There are discussed a lesser severity of coronary lesions and left ventricular dysfunction, or a reduced prevalence of moderate-severe chronic obstructive pulmonary disease in patients selected for surgery. On the other hand, the constellation of data which supports purposeful weight reduction in the prevention and treatment of cardiovascular diseases, induces a controversial position regarding this new concept.

  11. A dynamic model of oceanic sulfur (DMOS) applied to the Sargasso Sea: Simulating the dimethylsulfide (DMS) summer paradox

    Science.gov (United States)

    Vallina, S. M.; Simó, R.; Anderson, T. R.; Gabric, A.; Cropp, R.; Pacheco, J. M.

    2008-03-01

    A new one-dimensional model of DMSP/DMS dynamics (DMOS) is developed and applied to the Sargasso Sea in order to explain what drives the observed dimethylsulfide (DMS) summer paradox: a summer DMS concentration maximum concurrent with a minimum in the biomass of phytoplankton, the producers of the DMS precursor dimethylsulfoniopropionate (DMSP). Several mechanisms have been postulated to explain this mismatch: a succession in phytoplankton species composition towards higher relative abundances of DMSP producers in summer; inhibition of bacterial DMS consumption by ultraviolet radiation (UVR); and direct DMS production by phytoplankton due to UVR-induced oxidative stress. None of these hypothetical mechanisms, except for the first one, has been tested with a dynamic model. We have coupled a new sulfur cycle model that incorporates the latest knowledge on DMSP/DMS dynamics to a preexisting nitrogen/carbon-based ecological model that explicitly simulates the microbial-loop. This allows the role of bacteria in DMS production and consumption to be represented and quantified. The main improvements of DMOS with respect to previous DMSP/DMS models are the explicit inclusion of: solar-radiation inhibition of bacterial sulfur uptakes; DMS exudation by phytoplankton caused by solar-radiation-induced stress; and uptake of dissolved DMSP by phytoplankton. We have conducted a series of modeling experiments where some of the DMOS sulfur paths are turned "off" or "on," and the results on chlorophyll-a, bacteria, DMS, and DMSP (particulate and dissolved) concentrations have been compared with climatological data of these same variables. The simulated rate of sulfur cycling processes are also compared with the scarce data available from previous works. All processes seem to play a role in driving DMS seasonality. Among them, however, solar-radiation-induced DMS exudation by phytoplankton stands out as the process without which the model is unable to produce realistic DMS simulations

  12. EARTHQUAKE SCALING PARADOX

    Institute of Scientific and Technical Information of China (English)

    WU ZHONG-LIANG

    2001-01-01

    Two measures of earthquakes, the seismic moment and the broadband radiated energy, show completely different scaling relations. For shallow earthquakes worldwide from January 1987 to December 1998, the frequency distribution of the seismic moment shows a clear kink between moderate and large earthquakes, as revealed by previous works. But the frequency distribution of the broadband radiated energy shows a single power law, a classical Gutenberg-Richter relation. This inconsistency raises a paradox in the self-organized criticality model of earthquakes.

  13. Identity paradoxes

    Directory of Open Access Journals (Sweden)

    Đurić Jelena

    2010-01-01

    Full Text Available The article considers paradoxical nature of identity that emerges from: 1 the very concept of identity whose abstract generality unites various and even opposite features; 2 the processual nature of reality that is easier to express in the poetical metaphors or abstract principles than in unambiguous conceptual networks; 3 the oppose relationship between being and knowledge, mind and matter, subject and object, self and personality. Entangled in the labyrinth which evade efforts to be conceptually defined, the modern thinking of identity moves towards abandoning the idea of “self” on behalf of the “ego” and towards the misapprehension of identity as being identical. This corresponds to the “time of the lost spirit” stretched between the simultaneous need to find an identity and to give it up.

  14. Fair pricing, and pricing paradoxes

    Directory of Open Access Journals (Sweden)

    Barbara Swart

    2016-05-01

    Full Text Available The St Petersburg Paradox revolves round the determination of a fair price for playing the St Petersburg Game. According to the original formulation, the price for the game is infinite, and, therefore, paradoxical. Although the St Petersburg Paradox can be seen as concerning merely a game, Paul Samuelson (1977 calls it a “fascinating chapter in the history of ideas”, a chapter that gave rise to a considerable number of papers over more than 200 years involving fields such as probability theory and economics. In a paper in this journal, Vivian (2013 undertook a numerical investigation of the St Petersburg Game. In this paper, the central issue of the paradox is identified as that of fair (risk-neutral pricing, which is fundamental in economics and finance and involves important concepts such as no arbitrage, discounting, and risk-neutral measures. The model for the St Petersburg Game as set out in this paper is new and analytical and resolves the so-called pricing paradox by applying a discounting procedure. In this framework, it is shown that there is in fact no infinite price paradox, and simple formulas for obtaining a finite price for the game are also provided.

  15. A Mosquito in the Classroom: Using the Cooperative Business Model to Foster Paradoxical Thinking in Management Education

    Science.gov (United States)

    Audebrand, Luc K.; Camus, Annie; Michaud, Valérie

    2017-01-01

    Although the paradox perspective is gaining increasing attention among management scholars, most of us continue to struggle with addressing this challenging topic in the classroom, as it seems out of reach for many students. In this article, we describe a potentially beneficial way to approach paradoxical thinking in management education: teaching…

  16. Beyond Parrondo's Paradox

    Science.gov (United States)

    SHU, Jian-Jun; WANG, Qi-Wen

    2014-01-01

    The Parrondo's paradox is a counterintuitive phenomenon where individually-losing strategies can be combined in producing a winning expectation. In this paper, the issues surrounding the Parrondo's paradox are investigated. The focus is lying on testifying whether the same paradoxical effect can be reproduced by using a simple capital dependent game. The paradoxical effect generated by the Parrondo's paradox can be explained by placing all the parameters in one probability space. Based on this framework, it is able to generate other possible paradoxical effects by manipulating the parameters in the probability space. PMID:24577586

  17. Paradoxical effects of all-trans-retinoic acid on lupus-like disease in the MRL/lpr mouse model.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Liao

    Full Text Available Roles of all-trans-retinoic acid (tRA, a metabolite of vitamin A (VA, in both tolerogenic and immunogenic responses are documented. However, how tRA affects the development of systemic autoimmunity is poorly understood. Here we demonstrate that tRA have paradoxical effects on the development of autoimmune lupus in the MRL/lpr mouse model. We administered, orally, tRA or VA mixed with 10% of tRA (referred to as VARA to female mice starting from 6 weeks of age. At this age, the mice do not exhibit overt clinical signs of lupus. However, the immunogenic environment preceding disease onset has been established as evidenced by an increase of total IgM/IgG in the plasma and expansion of lymphocytes and dendritic cells in secondary lymphoid organs. After 8 weeks of tRA, but not VARA treatment, significantly higher pathological scores in the skin, brain and lung were observed. These were accompanied by a marked increase in B-cell responses that included autoantibody production and enhanced expression of plasma cell-promoting cytokines. Paradoxically, the number of lymphocytes in the mesenteric lymph node decreased with tRA that led to significantly reduced lymphadenopathy. In addition, tRA differentially affected renal pathology, increasing leukocyte infiltration of renal tubulointerstitium while restoring the size of glomeruli in the kidney cortex. In contrast, minimal induction of inflammation with tRA in the absence of an immunogenic environment in the control mice was observed. Altogether, our results suggest that under a predisposed immunogenic environment in autoimmune lupus, tRA may decrease inflammation in some organs while generating more severe disease in others.

  18. Sheldon Spectrum and the Plankton Paradox: Two Sides of the Same Coin. A trait-based plankton size-spectrum model

    CERN Document Server

    Cuesta, José A; Law, Richard

    2016-01-01

    The Sheldon spectrum describes a remarkable regularity in aquatic ecosystems: the biomass density as a function of logarithmic body mass is approximately constant over many orders of magnitude. While size-spectrum models have explained this phenomenon for assemblages of multicellular organisms, this paper introduces a species-resolved size-spectrum model to explain the phenomenon in unicellular plankton. A Sheldon spectrum spanning the cell-size range of unicellular plankton necessarily consists of a large number of coexisting species covering a wide range of characteristic sizes. The coexistence of many phytoplankton species feeding on a small number of resources is known as the Paradox of the Plankton. Our model resolves the paradox by showing that coexistence is facilitated by the allometric scaling of four physiological rates. Two of the allometries have empirical support, the remaining two emerge from predator-prey interactions exactly when the abundances follow a Sheldon spectrum. Our plankton model is ...

  19. Solutions to Organizational Paradox

    DEFF Research Database (Denmark)

    Li, Xin; Worm, Verner; Peihong, Xie

    Organizations face all kinds of paradoxical problems. There exist various solutions to organizational paradoxes. We develop a typology that lists nine possible logical approaches to understanding the relationship between paradoxical opposites, out of which we identify five types of solutions...... to organizational paradox. Four of the five solutions are explicitly associated with four prominent philosophies. We show the relevance of the five solutions to the real world by applying our scheme to understand different solutions to the generic strategy paradox. Finally, we address the question whether...

  20. Invariant Bayesian Inference in Regression Models that is robust against the Jeffreys-Lindley's paradox

    NARCIS (Netherlands)

    Kleibergen, F.

    2003-01-01

    We obtain the prior and posterior probability of a nested regression model as the Hausdorff-integral of the prior and posterior on the parameters of an encompassing linear regression model over a lower dimensional set that represents the nested model. The invariant expression of the

  1. Invariant Bayesian Inference in Regression Models that is robust against the Jeffreys-Lindleys Paradox

    NARCIS (Netherlands)

    Kleibergen, F.R.

    2004-01-01

    We obtain the prior and posterior probability of a nested regression model as the Hausdorff-integral of the prior and posterior on the parameters of an encompassing linear regression model over a lower-dimensional set that represents the nested model. The Hausdorff-integral is invariant and

  2. Economic Growth, Capitalism and Unknown Economic Paradoxes

    Directory of Open Access Journals (Sweden)

    Andzela Mialik

    2012-10-01

    Full Text Available The paper deals with failures of capitalism or free market and presents the results of economic analysis by applying a logistic capital growth model. The application of a logistic growth model for analysis of economic bubbles reveals the fundamental causes of bubble formation—economic paradoxes related with phenomena of saturated markets: the paradox of growing returnability and the paradoxes of debt and leverage trap. These paradoxes occur exclusively in the saturated markets and cause the majority of economic problems of recent days including overproduction, economic bubbles and cyclic economic development. Unfortunately, these paradoxes have not been taken into account when dealing with the current failures of capitalism. The aim of the paper is to apply logistic capital growth models for the analysis of economic paradoxes having direct impact on the capitalism failures such as economic bubbles, economic crisis and unstable economic growth. The analysis of economic paradoxes and their implication son failures of capitalism provided in the paper presents the new approach in developing policies aimed at increasing economic growth stability and overcoming failures of capitalism.

  3. The Integration Paradox

    Science.gov (United States)

    Verkuyten, Maykel

    2016-01-01

    The integration paradox refers to the phenomenon of the more highly educated and structurally integrated immigrants turning away from the host society, rather than becoming more oriented toward it. This article provides an overview of the empirical evidence documenting this paradox in the Netherlands. In addition, the theoretical arguments and the available findings about the social psychological processes involved in this paradox are considered. The existing evidence for the integration paradox and what might explain it form the basis for making suggestion for future theoretical work and empirical research, and for discussing possible policy implications. PMID:27152028

  4. Mathematical fallacies and paradoxes

    CERN Document Server

    Bunch, Bryan

    1982-01-01

    Stimulating, thought-provoking analysis of the most interesting intellectual inconsistencies in mathematics, physics, and language, including being led astray by algebra (De Morgan's paradox). 1982 edition.

  5. The autophagic tumor stroma model of cancer or "battery-operated tumor growth": A simple solution to the autophagy paradox.

    Science.gov (United States)

    Martinez-Outschoorn, Ubaldo E; Whitaker-Menezes, Diana; Pavlides, Stephanos; Chiavarina, Barbara; Bonuccelli, Gloria; Casey, Trimmer; Tsirigos, Aristotelis; Migneco, Gemma; Witkiewicz, Agnieszka; Balliet, Renee; Mercier, Isabelle; Wang, Chengwang; Flomenberg, Neal; Howell, Anthony; Lin, Zhao; Caro, Jaime; Pestell, Richard G; Sotgia, Federica; Lisanti, Michael P

    2010-11-01

    The role of autophagy in tumorigenesis is controversial. Both autophagy inhibitors (chloroquine) and autophagy promoters (rapamycin) block tumorigenesis by unknown mechanism(s). This is called the "Autophagy Paradox". We have recently reported a simple solution to this paradox. We demonstrated that epithelial cancer cells use oxidative stress to induce autophagy in the tumor microenvironment. As a consequence, the autophagic tumor stroma generates recycled nutrients that can then be used as chemical building blocks by anabolic epithelial cancer cells. This model results in a net energy transfer from the tumor stroma to epithelial cancer cells (an energy imbalance), thereby promoting tumor growth. This net energy transfer is both unilateral and vectorial, from the tumor stroma to the epithelial cancer cells, representing a true host-parasite relationship. We have termed this new paradigm "The Autophagic Tumor Stroma Model of Cancer Cell Metabolism" or "Battery-Operated Tumor Growth". In this sense, autophagy in the tumor stroma serves as a "battery" to fuel tumor growth, progression and metastasis, independently of angiogenesis. Using this model, the systemic induction of autophagy will prevent epithelial cancer cells from using recycled nutrients, while the systemic inhibiton of autophagy will prevent stromal cells from producing recycled nutrients-both effectively "starving" cancer cells. We discuss the idea that tumor cells could become resistant to the systemic induction of autophagy, by the upregulation of natural endogenous autophagy inhibitors in cancer cells. Alternatively, tumor cells could also become resistant to the systemic induction of autophagy, by the genetic silencing/deletion of pro-autophagic molecules, such as Beclin1. If autophagy resistance develops in cancer cells, then the systemic inhibition of autophagy would provide a therapeutic solution to this type of drug resistance, as it would still target autophagy in the tumor stroma. As such, an

  6. Modulation of VEGF signaling in a mouse model of diabetes by xanthohumol and 8-prenylnaringenin: Unveiling the angiogenic paradox and metabolism interplay.

    Science.gov (United States)

    Costa, Raquel; Rodrigues, Ilda; Guardão, Luísa; Lima, Joana Quelhas; Sousa, Emília; Soares, Raquel; Negrão, Rita

    2017-04-01

    Imbalance in kidney and heart neovascularization is common in type2 diabetes (T2DM) patients. Nevertheless, the mechanisms governing this angiogenic paradox have not been elucidated. Xanthohumol (XN) and 8-prenylnaringenin (8PN) beer polyphenols modulate angiogenesis, being thus targets for T2DM-related complications. Our work examined whether polyphenols consumption affects angiogenic paradox and metabolism in a T2DM mouse model. An increase in kidney and a reduction in left ventricle (LV) microvessels of diabetic C57Bl/6 mice were observed. XN consumption reduced angiogenesis, VEGFR-2 expression/activity, VEGF-A and phosphofructokinase-2/fructose-2,6-bisphosphatase-3 enzyme expression, a metabolic marker present in endothelial tip cells in T2DM mice kidney. 8PN had opposite effects in T2DM mice LV. These XN and 8PN effects were dependent on VEGF levels as revealed by in vitro assays. These findings were accompanied by tissue and plasma reduced expression levels of VEGF-B and its receptors, VEGFR1 and neuropilin-1, by both polyphenols. Beer polyphenols modulate T2DM angiogenic paradox in a tissue-dependent manner. We also show for the first time that both polyphenols decreased VEGF-B pathway, which is implicated in endothelial-to-tissue lipid metabolism. Altogether, the effects of these polyphenols in the crosstalk between angiogenesis and metabolism render them potent agents for novel diabetic therapeutic interventions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A "Position Paradox" in Sponsored Search Auctions

    OpenAIRE

    Kinshuk Jerath; Liye Ma; Young-Hoon Park; Kannan Srinivasan

    2011-01-01

    We study the bidding strategies of vertically differentiated firms that bid for sponsored search advertisement positions for a keyword at a search engine. We explicitly model how consumers navigate and click on sponsored links based on their knowledge and beliefs about firm qualities. Our model yields several interesting insights; a main counterintuitive result we focus on is the "position paradox." The paradox is that a superior firm may bid lower than an inferior firm and obtain a position ...

  8. Gray's paradox: A fluid mechanical perspective

    Science.gov (United States)

    Bale, Rahul; Hao, Max; Bhalla, Amneet Pal Singh; Patel, Namrata; Patankar, Neelesh A.

    2014-01-01

    Nearly eighty years ago, Gray reported that the drag power experienced by a dolphin was larger than the estimated muscle power – this is termed as Gray's paradox. We provide a fluid mechanical perspective of this paradox. The viewpoint that swimmers necessarily spend muscle energy to overcome drag in the direction of swimming needs revision. For example, in undulatory swimming most of the muscle energy is directly expended to generate lateral undulations of the body, and the drag power is balanced not by the muscle power but by the thrust power. Depending on drag model utilized, the drag power may be greater than muscle power without being paradoxical. PMID:25082341

  9. Paradoxes in dermatology

    Directory of Open Access Journals (Sweden)

    Keshavmurthy A Adya

    2013-01-01

    Full Text Available Many paradoxical phenomena related to clinical, immunological, and therapeutic dermatology have been described. While some of them can be explained logically, the cause for others can only be speculated. Whenever encountered in clinical practice, background knowledge of such paradoxes may be useful to the clinician.

  10. Paradoxes in probability theory

    CERN Document Server

    Eckhardt, William

    2013-01-01

    Paradoxes provide a vehicle for exposing misinterpretations and misapplications of accepted principles. This book discusses seven paradoxes surrounding probability theory.  Some remain the focus of controversy; others have allegedly been solved, however the accepted solutions are demonstrably incorrect. Each paradox is shown to rest on one or more fallacies.  Instead of the esoteric, idiosyncratic, and untested methods that have been brought to bear on these problems, the book invokes uncontroversial probability principles, acceptable both to frequentists and subjectivists. The philosophical disputation inspired by these paradoxes is shown to be misguided and unnecessary; for instance, startling claims concerning human destiny and the nature of reality are directly related to fallacious reasoning in a betting paradox, and a problem analyzed in philosophy journals is resolved by means of a computer program.

  11. Paradoxical leanness in the imprinting-centre deletion mouse model for Prader-Willi syndrome.

    Science.gov (United States)

    Golding, David M; Rees, Daniel J; Davies, Jennifer R; Relkovic, Dinko; Furby, Hannah V; Guschina, Irina A; Hopkins, Anna L; Davies, Jeffrey S; Resnick, James L; Isles, Anthony R; Wells, Timothy

    2017-01-01

    Prader-Willi syndrome (PWS), a neurodevelopmental disorder caused by loss of paternal gene expression from 15q11-q13, is characterised by growth retardation, hyperphagia and obesity. However, as single gene mutation mouse models for this condition display an incomplete spectrum of the PWS phenotype, we have characterised the metabolic impairment in a mouse model for 'full' PWS, in which deletion of the imprinting centre (IC) abolishes paternal gene expression from the entire PWS cluster. We show that PWS-IC(del) mice displayed postnatal growth retardation, with reduced body weight, hyperghrelinaemia and marked abdominal leanness; proportionate retroperitoneal, epididymal/omental and inguinal white adipose tissue (WAT) weights being reduced by 82%, 84% and 67%, respectively. PWS-IC(del) mice also displayed a 48% reduction in proportionate interscapular brown adipose tissue (isBAT) weight with significant 'beiging' of abdominal WAT, and a 2°C increase in interscapular surface body temperature. Maintenance of PWS-IC(del) mice under thermoneutral conditions (30°C) suppressed the thermogenic activity in PWS-IC(del) males, but failed to elevate the abdominal WAT weight, possibly due to a normalisation of caloric intake. Interestingly, PWS-IC(del) mice also showed exaggerated food hoarding behaviour with standard and high-fat diets, but despite becoming hyperphagic when switched to a high-fat diet, PWS-IC(del) mice failed to gain weight. This evidence indicates that, unlike humans with PWS, loss of paternal gene expression from the PWS cluster in mice results in abdominal leanness. Although reduced subcutaneous insulation may lead to exaggerated heat loss and thermogenesis, abdominal leanness is likely to arise from a reduced lipid storage capacity rather than increased energy utilisation in BAT. © 2017 The authors.

  12. Paradoxical effects of KB-R7943 on arrhythmogenicity in a chronic myocardial infarction rabbit model.

    Science.gov (United States)

    Chang, Po-Cheng; Wo, Hung-Ta; Lee, Hui-Ling; Wen, Ming-Shien; Chou, Chung-Chuan

    2015-07-01

    Na(+)/Ca(2+) exchanger blockade has been reported to be anti-arrhythmic in different models. The effects of KB-R7943, a Na(+)/Ca(2+) exchanger blocker, on arrhythmogenesis in hearts with chronic myocardial infarction (MI) remain unclear. Dual voltage and intracellular Ca(2+) (Cai) optical mapping was performed in nine rabbit hearts with chronic MI and four control hearts. Electrophysiology studies including inducibility of ventricular tachyarrhythmias, ventricular fibrillation dominant frequency, action potential, Cai alternans, Cai decay, and conduction velocity were performed. The same protocol was repeated in the presence of KB-R7943 (0.5, 1, and 5μM) after the baseline studies. KB-R7943 was effective in suppressing afterdepolarizations and spontaneous ventricular tachyarrhythmias in hearts with chronic MI. Surprisingly, KB-R7943 increased the inducibility of ventricular tachyarrhythmias in a dose-dependent manner (11%, 11%, 22%, and 56% at baseline and with 0.5, 1, and 5μM KB-R7943, respectively, p=0.02). Optical mapping analysis revealed that the underlying mechanisms of the induced ventricular tachyarrhythmias were probably spatially discordant alternans with wave breaks and rotors. Further analysis showed that KB-R7943 significantly enhanced both action potential (p=0.033) and Cai (p=0.001) alternans, prolonged Cai decay (tau value) in a dose-dependent manner (p=0.004), and caused heterogeneous conduction delay especially at peri-infarct zones during rapid burst pacing. In contrast, KB-R7943 had insignificant effects in control hearts. In this chronic MI rabbit model, KB-R7943 has contrasting effects on arrhythmogenesis, suppressing afterdepolarizations and spontaneous ventricular tachyarrhythmias, but enhancing the inducibility of tachyarrhythmias. The mechanism is probably the enhanced spatially discordant alternans because of prolonged Cai decay and heterogeneous conduction delay. Copyright © 2014 Japanese College of Cardiology. Published by Elsevier

  13. Sheldon spectrum and the plankton paradox: two sides of the same coin-a trait-based plankton size-spectrum model.

    Science.gov (United States)

    Cuesta, José A; Delius, Gustav W; Law, Richard

    2017-05-25

    The Sheldon spectrum describes a remarkable regularity in aquatic ecosystems: the biomass density as a function of logarithmic body mass is approximately constant over many orders of magnitude. While size-spectrum models have explained this phenomenon for assemblages of multicellular organisms, this paper introduces a species-resolved size-spectrum model to explain the phenomenon in unicellular plankton. A Sheldon spectrum spanning the cell-size range of unicellular plankton necessarily consists of a large number of coexisting species covering a wide range of characteristic sizes. The coexistence of many phytoplankton species feeding on a small number of resources is known as the Paradox of the Plankton. Our model resolves the paradox by showing that coexistence is facilitated by the allometric scaling of four physiological rates. Two of the allometries have empirical support, the remaining two emerge from predator-prey interactions exactly when the abundances follow a Sheldon spectrum. Our plankton model is a scale-invariant trait-based size-spectrum model: it describes the abundance of phyto- and zooplankton cells as a function of both size and species trait (the maximal size before cell division). It incorporates growth due to resource consumption and predation on smaller cells, death due to predation, and a flexible cell division process. We give analytic solutions at steady state for both the within-species size distributions and the relative abundances across species.

  14. The Simpson's paradox unraveled

    Science.gov (United States)

    Hernán, Miguel A; Clayton, David; Keiding, Niels

    2011-01-01

    Background In a famous article, Simpson described a hypothetical data example that led to apparently paradoxical results. Methods We make the causal structure of Simpson's example explicit. Results We show how the paradox disappears when the statistical analysis is appropriately guided by subject-matter knowledge. We also review previous explanations of Simpson's paradox that attributed it to two distinct phenomena: confounding and non-collapsibility. Conclusion Analytical errors may occur when the problem is stripped of its causal context and analyzed merely in statistical terms. PMID:21454324

  15. The Simpson's paradox unraveled

    DEFF Research Database (Denmark)

    Hernán, Miguel A; Clayton, David; Keiding, Niels

    2011-01-01

    Background In a famous article, Simpson described a hypothetical data example that led to apparently paradoxical results. Methods We make the causal structure of Simpson’s example explicit. Results We show how the paradox disappears when the statistical analysis is appropriately guided by subject......-matter knowledge. We also review previous explanations of Simpson’s paradox that attributed it to two distinct phenomena: confounding and non-collapsibility. Conclusion Analytical errors may occur when the problem is stripped of its causal context and analyzed merely in statistical terms....

  16. Many Worlds Model resolving the Einstein Podolsky Rosen paradox via a Direct Realism to Modal Realism Transition that preserves Einstein Locality

    CERN Document Server

    Vongehr, Sascha

    2011-01-01

    The violation of Bell inequalities by quantum physical experiments disproves all relativistic micro causal, classically real models, short Local Realistic Models (LRM). Non-locality, the infamous "spooky interaction at a distance" (A. Einstein), is already sufficiently 'unreal' to motivate modifying the "realistic" in "local realistic". This has led to many worlds and finally many minds interpretations. We introduce a simple many world model that resolves the Einstein Podolsky Rosen paradox. The model starts out as a classical LRM, thus clarifying that the many worlds concept alone does not imply quantum physics. Some of the desired non-locality, e.g. anti-correlation at equal measurement angles, is already present, but Bell's inequality can of course not be violated. A single and natural step turns this LRM into a quantum model predicting the correct probabilities. Intriguingly, the crucial step does obviously not modify locality but instead reality: What before could have still been a direct realism turns i...

  17. Thermal Expansion "Paradox."

    Science.gov (United States)

    Fakhruddin, Hasan

    1993-01-01

    Describes a paradox in the equation for thermal expansion. If the calculations for heating a rod and subsequently cooling a rod are determined, the new length of the cool rod is shorter than expected. (PR)

  18. Glycogen synthase kinase-3β inhibition in the medial prefrontal cortex mediates paradoxical amphetamine action in a mouse model of ADHD

    Directory of Open Access Journals (Sweden)

    Yi-Chun eYen

    2015-03-01

    Full Text Available Psychostimulants show therapeutic efficacy in the treatment of attention-deficit hyperactivity disorder (ADHD. It is generally assumed that they ameliorate ADHD symptoms via interfering with monoaminergic signaling. We combined behavioral pharmacology, neurochemistry and molecular analyses to identify mechanisms underlying the paradoxical calming effect of amphetamine in low trait anxiety behavior (LAB mice, a novel multigenetic animal model of ADHD. Amphetamine (1 mg/kg and methylphenidate (10 mg/kg elicited similar dopamine and norepinephrine release in the medial prefrontal cortex (mPFC and in the striatum of LAB mice. In contrast, amphetamine decreased, while methylphenidate increased locomotor activity. This argues against changes in dopamine and/or norepinephrine release as mediators of amphetamine paradoxical effects. Instead, the calming activity of amphetamine corresponded to the inhibition of glycogen synthase kinase3β (GSK3β activity, specifically in the mPFC. Accordingly, not only systemic administration of the GSK3β inhibitor TDZD-8 (20 mg/kg, but also local microinjections of TDZD-8 and amphetamine into the mPFC, but not into the striatum, decreased locomotor activity in LAB mice. Amphetamine effects seem to depend on NMDA receptor signaling, since pre- or co-treatment with MK-801 (0.3 mg/kg abolished the effects of amphetamine (1 mg/kg on the locomotion and on the phosphorylation of GSK3β at the level of the mPFC. Taken together, the paradoxical calming effect of amphetamine in hyperactive LAB mice concurs with a decreased GSK3β activity in the mPFC. This effect appears to be independent of dopamine or norepinephrine release, but contingent on NMDA receptor signaling.

  19. Man Is a Paradox

    Institute of Scientific and Technical Information of China (English)

    王茂娟

    2009-01-01

    In the poem "Always", the author Pablo Neruda employs the first person narration to incisively reveal the paradoxical traits in human nature by exploring man in relation to love. "I" play a role shifting from a calm narrator to a furious one, and the last recovering to a mild one, which offers a multiple visual angle to observe humanity. In sum, by means of continuous changes of my inner feelings in the poem, Pablo Neruda reveals the paradoxical humanity .

  20. The core paradox.

    Science.gov (United States)

    Kennedy, G. C.; Higgins, G. H.

    1973-01-01

    Rebuttal of suggestions from various critics attempting to provide an escape from the seeming paradox originated by Higgins and Kennedy's (1971) proposed possibility that the liquid in the outer core was thermally stably stratified and that this stratification might prove a powerful inhibitor to circulation of the outer core fluid of the kind postulated for the generation of the earth's magnetic field. These suggestions are examined and shown to provide no reasonable escape from the core paradox.

  1. The Fontana paradoxical reflex?

    Science.gov (United States)

    Lavorini, Federico; Fontana, Giovanni; Chellini, Elisa; Magni, Chiara; Pistolesi, Massimo; Widdicombe, John

    2011-09-01

    This commentary describes the "deflation cough" caused by deep lung deflations. Deflation cough is a paradoxical reflex similar to that described by Henry Head in 1889 for lung inflations that probably is mediated by the same sensors and afferent fibers in the lungs and activated by gastroesophageal reflux. We discuss how this reflex must be self-limiting, the general role of paradoxical reflexes in the body, and the possible clinical significance of deflation cough.

  2. Giffen's Paradox and Falsifiability

    OpenAIRE

    Gordon Welty

    2004-01-01

    This paper considers the methodological problem which the Giffen paradox poses for the economist intent on establishing the empirical status of microeconomic theory. We then turn to more general considerations of the falsifiability of economic theory based on discussions by Adolf Grünbaum. These considerations lead us to reject Louis De Alessi's proposal for rectifying the problem of the Giffen paradox. Finally, we turn to the problem of ceteris paribus as it bears on De Alessi's argument, an...

  3. The 'Sears paradox'

    CERN Document Server

    Franklin, Jerrold

    2014-01-01

    We resolve a paradox in special relativity proposed by F. W. Sears for the action of forces on a rigid body. In the paradox, a moving rigid rod is struck at different times by impulsive forces, but continues to move with unchanged velocity, with the forces having no effect. Our conclusion is that the usual laws of mechanics can be applied to a rigid body only in its rest system

  4. A Paradox Related to Mechanical and Electrical Energy Conversion

    CERN Document Server

    Li, Songyan

    2014-01-01

    A model is constructed and a paradox concerning the proper direction and magnitude of the external force to maintain the equilibrium state of a parallel plate capacitor system is raised. By a thorough study of the model using different methods, the paradox is eliminated.

  5. Braess like Paradox on Ladder Network

    CERN Document Server

    Toyota, Norihito

    2015-01-01

    Braess \\cite{1} has been studied about a traffic flow on a diamond type network and found that introducing new edges to the networks always does not achieve the efficiency. Some researchers studied the Braess' paradox in similar type networks by introducing various types of cost functions. But whether such paradox occurs or not is not scarcely studied in complex networks except for Dorogovtsev-Mendes network\\cite{2}. In this article, we study the paradox on Ladder type networks, as the first step to the research about Braess' paradox on Watts and Strogatz type small world network\\cite{Watt1}\\cite{Watt2}. %We theoretically and numerically studied Braess' paradox on Ladder networks. For the purpose, we construct $4 \\times 3$ models as extensions of the original Braess' models. We analyze theoretically and numerically studied the models on Ladder networks. Last we give a phase diagram for (a) model, where the cost functions of bypasses are constant =0 or flow, base on two parameters $r$ and $p$ by numerical simu...

  6. Zeno's Paradox of Immortality.

    Science.gov (United States)

    Olshansky, S Jay; Carnes, Bruce A

    2013-01-01

    Scientists who speculate on the future of human longevity have a broad range of views ranging from the promise of immortality, to radical life extension, to declines in life expectancy. Among those who contend that radical life extension is already here, or on the horizon, or immortality is forthcoming, elements of their reasoning appear surprisingly close, if not identical, to a famous mathematical paradox posed by the ancient Greek mathematician known as Zeno. Here we examine the underlying assumptions behind the views that much longer life expectancies are forthcoming or have already arrived, and place their line of reasoning within the context of a new Zeno paradox described here as The Paradox of Immortality. Copyright © 2012 S. Karger AG, Basel.

  7. Single Capacitor Paradox

    CERN Document Server

    Pankovic, Vladan

    2009-01-01

    In this work single capacitor paradox (a variation of the remarkable two capacitor paradox) is considered. Simply speaking in an ideal (without any electrical resistance and inductivity) electrical circuit with single charged capacitor and switch, by transition from initial, open state (switch in OFF position) in the final, closed state (switch in ON position), there is a total loss of the initial energy of the electrical field in condenser. Given energy loss can be simply explained without any dissipative effects (Joule heating or electromagnetic waves emission) by work of the electrical field by movement of the charge from one in the other plate of the capacitor. (Two capacitors paradox can be, obviously, explained in the analogous way.)

  8. Euthanasia: moral paradoxes.

    Science.gov (United States)

    ten Have, H A

    2001-11-01

    Over the past 30 years, euthanasia has been under continuous debate in The Netherlands. This contribution aims to provide a moral assessment of this debate. It is argued that euthanasia should be understood within a historical context, as a protest against medical power and as a way to bring about good death. Within the euthanasia debate, two paradoxes are identified which make the issue inherently complex and hard to regulate. The first paradox results from the dialectical relation between individual autonomy and relief of suffering as the major justifications of euthanasia. Although euthanasia represents an ultimate effort to give the individual patient control over his dying, the result of the debate is an increase of medical power. The second paradox is that although euthanasia emerged from a commitment to good death, it is resulting in a reduced range of options to bring about good death.

  9. Identifying Quantum Structures in the Ellsberg Paradox

    CERN Document Server

    Aerts, Diederik; Tapia, Jocelyn

    2013-01-01

    Empirical evidence has confirmed that quantum effects systematically occur also outside the microscopic domain, while quantum structures satisfactorily model various situations in several areas of science, including biological, cognitive and social processes. In this paper, we elaborate a quantum mechanical model which faithfully describes the 'Ellsberg paradox' in economics, showing that the mathematical formalism of quantum mechanics is capable to represent the 'ambiguity' present in this kind of situations, because of their 'contextuality'. Then, we analyze the data collected in a concrete experiment we performed on the Ellsberg paradox and work out a complete representation of them in complex Hilbert space, indicating that genuine quantum effects occur in the decision processes of the participants in the experiment. Our approach sheds light on 'ambiguity laden' decision processes in economics and decision theory, and allows to deal with different Ellsberg-type generalizations, e.g., the 'Machina paradox'.

  10. Motivation in Beyond Budgeting: A Motivational Paradox?

    DEFF Research Database (Denmark)

    Sandalgaard, Niels; Bukh, Per Nikolaj

    In this paper we discuss the role of motivation in relation to budgeting and we analyse how the Beyond Budgeting model functions compared with traditional budgeting. In the paper we focus on budget related motivation (and motivation in general) and conclude that the Beyond Budgeting model...... is a motivational paradox....

  11. Retrocausation, Consistency, and the Bilking Paradox

    Science.gov (United States)

    Dobyns, York H.

    2011-11-01

    Retrocausation seems to admit of time paradoxes in which events prevent themselves from occurring and thereby create a physical instance of the liar's paradox, an event which occurs iff it does not occur. The specific version in which a retrocausal event is used to trigger an intervention which prevents its own future cause is called the bilking paradox (the event is bilked of its cause). The analysis of Echeverria, Klinkhammer, and Thorne (EKT) suggests time paradoxes cannot arise even in the presence of retrocausation. Any self-contradictory event sequence will be replaced in reality by a closely related but noncontradictory sequence. The EKT analysis implies that attempts to create bilking must instead produce logically consistent sequences wherein the bilked event arises from alternative causes. Bilking a retrocausal information channel of limited reliability usually results only in failures of signaling. An exception applies when the bilking is conducted in response only to some of the signal values that can be carried on the channel. Theoretical analysis based on EKT predicts that, since some of the channel outcomes are not bilked, the channel is capable of transmitting data with its normal reliability, and the paradox-avoidance effects will instead suppress the outcomes that would lead to forbidden (bilked) transmissions. A recent parapsychological experiment by Bem displays a retrocausal information channel of sufficient reliability to test this theoretical model of physical reality's response to retrocausal effects. A modified version with partial bilking would provide a direct test of the generality of the EKT mechanism.

  12. The Paradox of Openness

    DEFF Research Database (Denmark)

    Laursen, Keld; Salter, Ammon

    2014-01-01

    To innovate, firms often need to draw from, and collaborate with, a large number of actors from outside their organization. At the same time, firms need also to be focused on capturing the returns from their innovative ideas. This gives rise to a paradox of openness—the creation of innovations of...

  13. A Hydrostatic Paradox Revisited

    Science.gov (United States)

    Ganci, Salvatore

    2012-01-01

    This paper revisits a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…

  14. A Hydrostatic Paradox Revisited

    Science.gov (United States)

    Ganci, Salvatore

    2012-01-01

    This paper revisits a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…

  15. Adiposopathy and Obesity Paradox

    Directory of Open Access Journals (Sweden)

    Indriyanti Rafi Sukmawati

    2013-04-01

    Full Text Available BACKGROUND: Obesity has reached global epidemic proportions in both adults and children and is associated with numerous comorbidities, including hypertension, type 2 diabetes mellitus (T2DM, dyslipidemia and major cardiovascular diseases (CVD. CONTENT: Adiposity may cause adipocyte and adipose tissue anatomic and functional abnormalities, termed adiposopathy (adipose-opathy or "sick fat," that result in endocrine and immune derangements. Adiposopathy may directly contribute to CVD through pericardiac and perivascular effects on the myocardium and blood vessels. Adiposopathy may also indirectly contribute to CVD through promoting or worsening major CVD risk factors such as T2DM, high blood pressure, and dyslipidemia. Despite this adverse association, numerous studies have documented an obesity paradox in which overweight and obese people with established CVD, including hypertension, heart failure, coronary heart disease, and peripheral arterial disease, have a better prognosis compared with nonoverweight/nonobese patients. These paradoxical findings are made less paradoxical when the pathogenic potential of excessive body fat is assessed based on adipose tissue dysfunction rather than simply on increased fat mass alone. SUMMARY: Adiposopathy is defined as pathological adipose tissue function that may be promoted and exacerbated by fat accumulation (adiposity and sedentary lifestyle in genetically susceptible patients. Adiposopathy is a root cause of some of the most common metabolic diseases observed in clinical practice, including T2DM, hypertension and dyslipidemia. KEYWORDS: adiposopathy, adiposity, obesity paradox, adipocyte dysfunction, adipose hypertrophy, adipose hyperplasia.

  16. Paradox and pleasure

    DEFF Research Database (Denmark)

    Iversen, Sara Mosberg

    2014-01-01

    Media use is a mundane activity which may nevertheless be highly pleasurable. Here the focus is on the articulated pleasures of playing the digital games The Sims 2 and The Sims 3. The paradox that relief from everyday chores is found in a game which to a great degree simulates similar activities...

  17. The paradoxical evolution of runoff in the pastoral Sahel: analysis of the hydrological changes over the Agoufou watershed (Mali) using the KINEROS-2 model

    Science.gov (United States)

    Gal, Laetitia; Grippa, Manuela; Hiernaux, Pierre; Pons, Léa; Kergoat, Laurent

    2017-09-01

    In recent decades, the Sahel has witnessed a paradoxical increase in surface water despite a general precipitation decline. This phenomenon, commonly referred to as the Sahelian paradox, is not completely understood yet. The role of cropland expansion due to the increasing food demand by a growing population has been often put forward to explain this situation for the cultivated Sahel. However, this hypothesis does not hold in pastoral areas where the same phenomenon is observed. Several other processes, such as the degradation of natural vegetation following the major droughts of the 1970s and the 1980s, the development of crusted topsoils, the intensification of the rainfall regime and the development of the drainage network, have been suggested to account for this situation. In this paper, a modeling approach is proposed to explore, quantify and rank different processes that could be at play in pastoral Sahel. The kinematic runoff and erosion model (KINEROS-2) is applied to the Agoufou watershed (245 km2), in the Gourma region in Mali, which underwent a significant increase of surface runoff during the last 60 years. Two periods are simulated, the past case (1960-1975) preceding the Sahelian drought and the present case (2000-2015). Surface hydrology and land cover characteristics for these two periods are derived by the analysis of aerial photographs, available in 1956, and high-resolution remote sensing images in 2011. The major changes identified are (1) a partial crusting of isolated dunes, (2) an increase of drainage network density, (3) a marked decrease in vegetation with the nonrecovery of tiger bush and vegetation growing on shallow sandy soils, and (4) important changes in soil properties with the apparition of impervious soils instead of shallow sandy soil. The KINEROS-2 model was parameterized to simulate these changes in combination or independently. The results obtained by this model display a significant increase in annual discharge between the

  18. The Paradoxes of Liberalism

    DEFF Research Database (Denmark)

    Thompson, Grahame

    2011-01-01

    Jakob Vestergaard has produced one of the most telling analyses of the international financial architecture by deploying a broadly Foucauldian framework that invokes a novel description of neo-liberal governance, one organized around discipline, conditional exceptions and the pursuit of a ‘proper...... economy’. This review both welcomes but challenges some of Vestergaard's analysis. In so doing it explores further the paradoxes of liberalism and the fate of sovereignty in the current international context....

  19. The Island Wind-Buoyancy Paradox

    Science.gov (United States)

    de Boer, A. M.; Nof, D.

    2003-04-01

    In recent years, a variety of studies have suggested that the meridional overturning circulation is at least partially controlled by the Southern Ocean winds. However, the overturning requires transformation of water masses, a process driven by buoyancy fluxes. This seems paradoxical as the wind and buoyancy fluxes are generally thought to be independent. The paradox is resolved qualitatively, using salinity and temperature mixed dynamical-box models, and quantitatively, employing a numerical model. The salinity and temperature box models suggest that stronger southern winds will tend to weaken the vertical and horizontal salinity stratification so that it is easier for the conversion of deep to surface water (and vice versa) to take place. The (process-orientated) reduced-gravity numerical model is adapted to include a thermodynamic parameterization for the surface heat and freshwater fluxes. In response to stronger southern winds, the thermocline thickens in the north, releasing more heat to the atmosphere and, thereby, converting more surface to deep water.

  20. Pentagrams and paradoxes

    CERN Document Server

    Badziag, Piotr; Cabello, Adan; Granstrom, Helena; Larsson, Jan-Ake

    2009-01-01

    Klyachko and coworkers consider an orthogonality graph in the form of a pentagram, and in this way derive a Kochen-Specker inequality for spin 1 systems. In some low-dimensional situations Hilbert spaces are naturally organised, by a magical choice of basis, into SO(N) orbits. Combining these ideas some very elegant results emerge. We give a careful discussion of the pentagram operator, and then show how the pentagram underlies a number of other quantum "paradoxes", such as that of Hardy.

  1. Extending Cantor Paradox

    CERN Document Server

    Leon, Antonio

    2008-01-01

    This paper examines infinity and self-reference from a critique perspective. Starting from an extension of Cantor Paradox that suggests the inconsistency of the actual infinite, the paper makes a short review of the controversial history of infinity and suggests several indicators of its inconsistency. Semantic self-reference is also examined from the same critique perspective by comparing it with self-referent sets. The platonic scenario of infinity and self-reference is finally criticized from a biological and neurobiological perspective.

  2. The Australian Paradox

    Directory of Open Access Journals (Sweden)

    Peter Howe

    2012-04-01

    Full Text Available Nutrients recently became the target of an unprecedented internet campaign by an individual who disagrees with the content and conclusions of a paper published in the journal last year, viz. “The Australian Paradox: A Substantial Decline in Sugars Intake over the Same Timeframe that Overweight and Obesity Have Increased” by Alan W. Barclay and Jennie Brand-Miller, Nutrients 2011, 3, 491–504. Regrettably, his criticism has extended to the journal and its peer review processes for permitting publication of the article. [...

  3. [The obesity paradox].

    Science.gov (United States)

    Du Pan, Rémi C Martin; Golay, Alain

    2014-06-25

    In general population, cardiovascular (CV) mortality increases in parallel with obesity severity, determined by body mass index (BMI). However in cohorts of patients with coronary diseases or heart failure a decrease of the global mortality has been observed in patients aged more than 65 years old with moderate obesity (BMI = 30-35) compared to normal weight people (BMI = 20-25) and morbid obese (BMI > 35). This "obesity paradox" could result from the selection of obese people with healthy metabolic profile and way of life. BMI does not allow to distinguish lean body mass from fat mass and therefore to evaluate abdominal obesity which is associated with metabolic syndrome and CV risk.

  4. [Obesity Paradox and Stroke].

    Science.gov (United States)

    Baumgartner, Ralf; Oesch, Lisa; Sarikaya, Hakan

    2016-07-06

    The obesity paradox suggests that overweight and obese patients of older age may have higher survival rates after stroke as compared to normalweight patients. However, the results need a cautious interpretation due to selection bias, treatment bias and different patients’ characteristics. Moreover, randomized studies that prove a benefit of weight reduction are still lacking. As obesity is an independet risk factor for stroke, weight reduction should still be recommended in overweight patients. Randomized-controlled studies are needed to prove the effect of weight reduction on morbidity and mortality after stroke.

  5. Professions, paradoxes and organizing

    DEFF Research Database (Denmark)

    Juel Jacobsen, Alice

    This paper empirically investigates organizational change in the making as it is constructed in the interaction between managers and professions in a school setting. The empirical basis is three Danish upper secondary schools, all in the process of translating a school reform into practice. Using...... an ethnographic approach and a concept of paradox as an exploring lens, the paper investigates the micro processes at work. The results of the empirical research point to challenging basic assumptions generated by the classical professions’ theory of autonomous and self-reliant professions. The paper contributes...

  6. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  7. Professions, paradoxes and organizing

    DEFF Research Database (Denmark)

    Juel Jacobsen, Alice

    This paper empirically investigates organizational change in the making as it is constructed in the interaction between managers and professions in a school setting. The empirical basis is three Danish upper secondary schools, all in the process of translating a school reform into practice. Using...... an ethnographic approach and a concept of paradox as an exploring lens, the paper investigates the micro processes at work. The results of the empirical research point to challenging basic assumptions generated by the classical professions’ theory of autonomous and self-reliant professions. The paper contributes...

  8. Paradoxes unbounded: Practising community making

    Directory of Open Access Journals (Sweden)

    Tess Maginess

    2011-10-01

    Full Text Available The first section of this paper is a discussion of the paradoxes contained in definitionsof the word 'community' and deliberately foregrounds and makes problematicconflicting meanings before arguing for a third definition and practice of community.This third definition and practice celebrates and even transcends contradictions withinan active learning model of education in the community, aimed at tackling inequalityand prejudice. The second section offers an autocritical narrative account of aneducation in the community project that illustrates how such a practice of communitymaking can be achieved within an educational framework in which pupil is teacher andteacher is pupil and in which an imaginative, creative approach is deployed toconstruct a community making practice. The paper draws on understandings fromcommunity development, inclusive and creative education, emancipatory actionresearch, postcolonial and post-structuralist theory.

  9. A Problem Study on Econometric Model Diversity Paradox%“计量模型多样性悖论”研究

    Institute of Scientific and Technical Information of China (English)

    俞立平; 刘骏

    2016-01-01

    在排除模型误用以后,将经济学研究中针对同一问题的研究,不同计量模型的结果各不相同,甚至结论截然相反问题称为“计量模型多样性悖论”。分析此问题产生的原因,主要是关键变量的多样性、方程形式设定的多样性和计量模型的多样性,提出采用元分析来解决这个问题,指出在元分析应用过程中应力求单个模型的精确,尽可能多地采用合适的模型,注意同类性质的结果才能进行元分析。同时,讨论元分析带来的新问题,比如对研究团队的计量经济学水平要求较高,增加了成本,延长了研究的时间,也加大了论文的篇幅等,但这是计量经济学发展过程中的正常现象,并不涉及采用元分析解决“计量模型多样性悖论”问题的科学性。%This paper will be on the same problems in the research of economics study ,the results of different econometric model each are not identical ,even conclusion is in contrast to the problem is known as the paradox of econometric model diversity after the exclusion of econometric model misuse .It analyzes the main causes of this problem is the diversity of key variables ,forms of equation and econometric model , and proposes to use meta analysis to solve this problem .It notes that we should seek a single accurate model ,as much as possible using a suitable model ,pay attention to the similar nature results in the meta‐analysis application process .The authors also discuss the new problems caused by meta analysis ,such as higher econometric level requirements for the research team ,increased costs ,extend the time to study , and also increased the length of the paper ,etc .But the authors think this is the normal phenomenon in the process of econometrics development and it does not involve the use of meta analysis to solve the"econometric model diversity paradox"problem scientifically .

  10. Simpson’s Paradox in Psychological Science: A Practical Guide

    Directory of Open Access Journals (Sweden)

    Rogier eKievit

    2013-08-01

    Full Text Available The direction of an association at the population-level may be reversed within the subgroups comprising that population—a striking observation called Simpson’s paradox. When facing this pattern, psychologists often view it as anomalous. Here, we argue that Simpson’s paradox is more common than conventionally thought, and typically results in incorrect interpretations – potentially with harmful consequences. We support this claim by drawing on empirical results from cognitive neuroscience, behavior genetics, psychopathology, personality psychology, educational psychology, intelligence research, and simulation studies. We show that Simpson’s Paradox is most likely to occur when inferences are drawn across different levels of explanation (e.g., from populations to subgroups, or subgroups to individuals. We propose a set of statistical markers indicative of the paradox, and offer psychometric solutions for dealing with the paradox when encountered—including a toolbox in R for detecting Simpson’s Paradox. We show that explicit modeling of situations in which the paradox might occur not only prevents incorrect interpretations of data, but also results in a deeper understanding of what data tell us about the world.

  11. Simpson's paradox in psychological science: a practical guide.

    Science.gov (United States)

    Kievit, Rogier A; Frankenhuis, Willem E; Waldorp, Lourens J; Borsboom, Denny

    2013-01-01

    The direction of an association at the population-level may be reversed within the subgroups comprising that population-a striking observation called Simpson's paradox. When facing this pattern, psychologists often view it as anomalous. Here, we argue that Simpson's paradox is more common than conventionally thought, and typically results in incorrect interpretations-potentially with harmful consequences. We support this claim by reviewing results from cognitive neuroscience, behavior genetics, clinical psychology, personality psychology, educational psychology, intelligence research, and simulation studies. We show that Simpson's paradox is most likely to occur when inferences are drawn across different levels of explanation (e.g., from populations to subgroups, or subgroups to individuals). We propose a set of statistical markers indicative of the paradox, and offer psychometric solutions for dealing with the paradox when encountered-including a toolbox in R for detecting Simpson's paradox. We show that explicit modeling of situations in which the paradox might occur not only prevents incorrect interpretations of data, but also results in a deeper understanding of what data tell us about the world.

  12. Paradoxical intention and recursive anxiety.

    Science.gov (United States)

    Ascher, L M; Schotte, D E

    1999-06-01

    The present study was designed to investigate a possible relationship between "recursive anxiety" and paradoxical intention. Groups of subjects were chosen from among individuals with public speaking concerns. and for whom fear of fear or recursive anxiety clearly represented an important element, or was completely absent from the clinical profile. These subjects were offered a standard in vivo treatment program for public speaking phobia with inclusion or exclusion of paradoxical intention. A 2 x 2 factorial design was employed. Those whose public speaking anxiety was complicated by recursive anxiety experienced greater improvement when paradoxical intention was included in the treatment program than when it was not employed. In contrast, individuals reporting simple public speaking phobia demonstrated greater success with a treatment program in which paradoxical intention was absent. Wegner's hypothesis of "ironic" cognitive processing was used to explain the proposed relationship between paradoxical intention and fear of fear.

  13. Yule-Simpson's Paradox in Research

    Directory of Open Access Journals (Sweden)

    Heather Honore Goltz

    2010-10-01

    Full Text Available Yule (1903 and Simpson (1951 described a statistical paradox that occurs when data is aggregated. In such situations, aggregated data may reveal a trend that directly contrasts those of sub-groups trends. In fact, the aggregate data trends may even be opposite in direction of sub-group trends. To reveal Yule-Simpson's paradox (YSP-type occurrences, researchers must simultaneously consider the effect of an intervention at specific levels and on the overall model to ensure datasets are accurately analyzed and research findings are appropriately interpreted. The primary objectives of this manuscript are to: (1 examine the history of YSP; (2 describe necessary and sufficient causes for YSP occurrences; (3 provide examples of YSP in research and explain YSP's relationship to multi-level modeling including Hierarchical Linear Modeling (HLM; and (4 discuss YSP's implications for researchers.

  14. EPR Paradox, Quantum Nonlocality and Physical Reality

    CERN Document Server

    Kupczynski, Marian

    2016-01-01

    Eighty years ago Einstein demonstrated that a particular interpretation of the reduction of wave function led to a paradox and that this paradox disappeared if statistical interpretation of quantum mechanics was adopted. According to the statistical interpretation a wave function describes only an ensemble of identically prepared physical systems. Searching for an intuitive explanation of long range correlations between outcomes of distant measurements, performed on pairs of physical systems prepared in a spin singlet state, John Bell analysed local realistic hidden variable models and proved that correlations consistent with these models satisfy Bell inequalities which are violated by some predictions of quantum mechanics. Several different local models were constructed, various inequalities proven and shown to be violated by experimental data. Some physicists concluded that Nature is definitely not local. We strongly disagree with this conclusion and we critically analyze some influential finite sample proo...

  15. A Resolution of the Paradox of Enrichment

    Science.gov (United States)

    Feng, Z. C.; Li, Y. Charles

    2015-06-01

    The paradox of enrichment was observed by Rosenzweig [1971] in a class of predator-prey models. Two of the parameters in the models are crucial for the paradox. These two parameters are the prey's carrying capacity and prey's half-saturation for predation. Intuitively, increasing the carrying capacity due to enrichment of the prey's environment should lead to a more stable predator-prey system. Analytically, it turns out that increasing the carrying capacity always leads to an unstable predator-prey system that is susceptible to extinction from environmental random perturbations. This is the so-called paradox of enrichment. Our resolution here rests upon a closer investigation on a dimensionless number H formed from the carrying capacity and the prey's half-saturation. By recasting the models into dimensionless forms, the models are in fact governed by a few dimensionless numbers including H. The effects of the two parameters: carrying capacity and half-saturation are incorporated into the number H. In fact, increasing the carrying capacity is equivalent (i.e. has the same effect on H) to decreasing the half-saturation which implies more aggressive predation. Since there is no paradox between more aggressive predation and instability of the predator-prey system, the paradox of enrichment is resolved. The so-called instability of the predator-prey system is characterized by the existence of a stable limit cycle in the phase plane, which gets closer and closer to the predator axis and prey axis. Due to random environmental perturbations, this can lead to extinction. We also further explore spatially dependent models for which the phase space is infinite-dimensional. The spatially independent limit cycle which is generated by a Hopf bifurcation from an unstable steady state, is linearly stable in the infinite-dimensional phase space. Numerical simulations indicate that the basin of attraction of the limit cycle is riddled. This shows that spatial perturbations can

  16. Paradoxical regulation of ChAT and nNOS expression in animal models of Crohn's colitis and ulcerative colitis

    OpenAIRE

    Winston, John H.; Li, Qingjie; Sarna, Sushil K.

    2013-01-01

    Morphological and functional changes in the enteric nervous system (ENS) have been reported in inflammatory bowel disease. We examined the effects of inflammation on the expression of choline acetyltransferase (ChAT) and nNOS in the muscularis externae of two models of colonic inflammation, trinitrobenzene sulfonic acid (TNBS)-induced colitis, which models Crohn's disease-like inflammation, and DSS-induced colitis, which models ulcerative Colitis-like inflammation. In TNBS colitis, we observe...

  17. The Painleve paradox in contact mechanics

    CERN Document Server

    Champneys, Alan R

    2016-01-01

    The 120-year old so-called Painleve paradox involves the loss of determinism in models of planar rigid bodies in point contact with a rigid surface, subject to Coulomb-like dry friction. The phenomenon occurs due to coupling between normal and rotational degrees-of-freedom such that the effective normal force becomes attractive rather than repulsive. Despite a rich literature, the forward evolution problem remains unsolved other than in certain restricted cases in 2D with single contact points. Various practical consequences of the theory are revisited, including models for robotic manipulators, and the strange behaviour of chalk when pushed rather than dragged across a blackboard. Reviewing recent theory, a general formulation is proposed, including a Poisson or energetic impact law. The general problem in 2D with a single point of contact is discussed and cases or inconsistency or indeterminacy enumerated. Strategies to resolve the paradox via contact regularisation are discussed from a dynamical systems po...

  18. Plotting Gothic: A Paradox

    Directory of Open Access Journals (Sweden)

    Stephen Murray

    2014-06-01

    Full Text Available The paradox of the title is that while most historians of medieval architecture agree that a combination of geometric and arithmetic methods was generally used to lay out a medieval church, there has been little consensus on the specifics of the process in relation to the design of any particular edifice. I begin by identifying four premises which underlie the debate. I then ask whether the new technologies — laser scanning and computer assisted design/drafting applications — can help. A case study uses newly generated point cloud data from a laser scan of the choir of Beauvais Cathedral. Finally, the notion of ‘plotting’ introduces essential sociological, anthropological and rhetorical dimensions. In the spirit of Roland Barthes ('Le plaisir du texte' and Peter Brooks ('Reading for the Plot', we can understand the urgency with which the architectural historian may seek to unscramble the hidden codes of the building as compulsive ‘reading for the plot’.

  19. Paradoxes in aerohydrodynamics

    CERN Document Server

    Yershin, Shakhbaz A

    2017-01-01

    This book, on the general topic of hydroaerodynamics, investigates a number of exciting applications in this field, addressing specifically issues that allow seemingly paradoxical issues to be dealt with. The first part is devoted to the study of channel flows, in particular the lateral flow of a viscous and viscous-plastic liquid in a ring channel formed by coaxial cylinders. Specifically, the problem of dissipation of mechanical energy in channel flows of highly viscous liquids is addressed and solved. Furthermore, the mechanism leading to hydrodynamic erosion in intra-field pipelines (known as "channelized effect") is identified. Subsequently, a theory for channel flows with mass transfer through porous walls is developed. In the second part, viscous liquid free flows (jets) are investigated. In particular, a dispersion law for turbulent flow is derived and the existence of dynamic invariance in wake flows of variable density is demonstrated. The third part presents new insights from both theoretical and e...

  20. Mimesis, fiction, paradoxes

    Directory of Open Access Journals (Sweden)

    Françoise Lavocat

    2010-04-01

    Full Text Available Les théories contemporaines de la fiction, comme les poétiques de la Renaissance, privilégient une conception de la mimesis fondée sur la vraisemblance : la démonstration du profit cognitif et moral de la fiction passe toujours par une définition de l’imitation (de quelque façon qu’on la définisse fondée sur la rationalité. L’auteur de cet article examine tout d’abord le statut des contradictions et de l’impossible chez quelques théoriciens actuels (principalement J.-M. Schaeffer, M.-L. Ryan, L. Doležel et poéticiens du 16e siècle (L. Castelvetro et F. Patrizi. Sont ensuite étudiées la forme et la fonction que prend l’impossible dans trois fictions narratives de la Renaissance. L’hypothèse majeure qui est défendue est que ces paradoxes permettent de penser le non-existant, dans la continuité de la scolastique médiévale et en relation avec une problématique religieuse, sérieuse ou parodique. Par là même, et en raison de leur auto-référentialité constitutive, les paradoxes inscrivent dans la fiction une réflexion sur elle-même qui n’a rien d’une apologie. La pensée de la fiction s’articule en définitive de façon bien différente dans les théories et dans les fictions elles-mêmes.Like Renaissance poetics, contemporary theories of fiction do favour a conception of mimesis based on likelihood. In order to underscore the benefits of fiction, in terms of cognition or ethics, both ancient and present-day authors usually identify imitation (however this is understood as a kind of rationality. The aim of this article is to question the status of contradictions and impossibilities, first in current theories of fiction (J-M Schaeffer, M.-L. Ryan, L. Doležel, then in two sixteenth century comments of Aristotle (by L. Castelvetro and F. Patrizi. In the following steps, forms and functions of the impossible are studied in three narratives of the Renaissance. The main hypothesis here is the following: in

  1. Reconsideration of the Paradox of Inquiry

    Science.gov (United States)

    Sato, Kunimasa

    2014-01-01

    It is well known that the Meno presents the argument called "the paradox of inquiry." This paper has two purposes. First, I analyze the paradox of inquiry and reformulate the argument as the "renewed paradox of inquiry." Second, I clarify that the problem of inquiry posed by this paradox concerns the necessary conditions for a…

  2. Reconsideration of the Paradox of Inquiry

    Science.gov (United States)

    Sato, Kunimasa

    2014-01-01

    It is well known that the Meno presents the argument called "the paradox of inquiry." This paper has two purposes. First, I analyze the paradox of inquiry and reformulate the argument as the "renewed paradox of inquiry." Second, I clarify that the problem of inquiry posed by this paradox concerns the necessary conditions for a…

  3. The paradox of enrichment in phytoplankton by induced competitive interactions

    Science.gov (United States)

    Tubay, Jerrold M.; Ito, Hiromu; Uehara, Takashi; Kakishima, Satoshi; Morita, Satoru; Togashi, Tatsuya; Tainaka, Kei-ichi; Niraula, Mohan P.; Casareto, Beatriz E.; Suzuki, Yoshimi; Yoshimura, Jin

    2013-01-01

    The biodiversity loss of phytoplankton with eutrophication has been reported in many aquatic ecosystems, e.g., water pollution and red tides. This phenomenon seems similar, but different from the paradox of enrichment via trophic interactions, e.g., predator-prey systems. We here propose the paradox of enrichment by induced competitive interactions using multiple contact process (a lattice Lotka-Volterra competition model). Simulation results demonstrate how eutrophication invokes more competitions in a competitive ecosystem resulting in the loss of phytoplankton diversity in ecological time. The paradox is enhanced under local interactions, indicating that the limited dispersal of phytoplankton reduces interspecific competition greatly. Thus, the paradox of enrichment appears when eutrophication destroys an ecosystem either by elevated interspecific competition within a trophic level and/or destabilization by trophic interactions. Unless eutrophication due to human activities is ceased, the world's aquatic ecosystems will be at risk. PMID:24089056

  4. Fantaisies et paradoxes mathématiques

    CERN Document Server

    Northrop, E P

    1964-01-01

    Qu'est-ce qu'un paradoxe ? ; quelques casse-tête simples (paradoxes pour tous) ; le puissant petit 2 et autres miracles... (paradoxes en arithmétique) ; je le vois, je ne le vois plus... (paradoxes en géométrie) ; tu ne diviseras pas par zéro... (sophismes algébriques) ; le voir, c'est le croire. Peut-être... (sophismes géométriques) ; toujours plus loin... (paradoxes de l'infini) ; combien de chances ? (paradoxes en probabilité) ; cercles vicieux (paradoxes en logique).

  5. The Risk of Paradoxical Embolism (RoPE Study: Developing risk models for application to ongoing randomized trials of percutaneous patent foramen ovale closure for cryptogenic stroke

    Directory of Open Access Journals (Sweden)

    Thaler David E

    2011-07-01

    Full Text Available Abstract Background Despite the diffusion into practice of percutaneous closure of a patent foramen ovale (PFO in patients with cryptogenic stroke (CS, the benefits have not been demonstrated, and remain unclear. For any individual presenting with a PFO in the setting of CS, it is not clear whether the PFO is pathogenically-related to the index event or an incidental finding. Further, the overall rate of stroke recurrence is low in patients with CS and PFO. How patient-specific factors affect the likelihood that a discovered PFO is related to an index stroke or affect the risk of recurrence is not well understood. These probabilities are likely to be important determinants of the benefits of PFO closure in CS. Design/Methods The goal of the Risk of Paradoxical Embolism (RoPE Study is to develop and test a set of predictive models that can identify those patients most likely to benefit from preventive treatments for PFO-related stroke recurrence, such as PFO closure. To do this, we will construct a database of patients with CS, both with and without PFO, by combining existing cohort studies. We will use this pooled database to identify patient characteristics associated with the presence (versus the absence of a PFO, and to use this "PFO propensity" to estimate the patient-specific probability that a PFO was pathogenically related to the index stroke (Model #1. We will also develop, among patients with both a CS and a PFO, a predictive model to estimate patient-specific stroke recurrence risk based on clinical, radiographic and echocardiographic characteristics. (Model #2. We will then combine Models #1 and #2 into a composite index that can rank patients with CS and PFO by their conditional probability that their PFO was pathogenically related to the index stroke and the risk of stroke recurrence. Finally, we will apply this composite index to completed clinical trials (currently on-going testing endovascular PFO closure against medical therapy

  6. Paradoxical regulation of ChAT and nNOS expression in animal models of Crohn's colitis and ulcerative colitis.

    Science.gov (United States)

    Winston, John H; Li, Qingjie; Sarna, Sushil K

    2013-08-15

    Morphological and functional changes in the enteric nervous system (ENS) have been reported in inflammatory bowel disease. We examined the effects of inflammation on the expression of choline acetyltransferase (ChAT) and nNOS in the muscularis externae of two models of colonic inflammation, trinitrobenzene sulfonic acid (TNBS)-induced colitis, which models Crohn's disease-like inflammation, and DSS-induced colitis, which models ulcerative Colitis-like inflammation. In TNBS colitis, we observed significant decline in ChAT, nNOS, and protein gene product (PGP) 9.5 protein and mRNA levels. In DSS colitis, ChAT and PGP9.5 were significantly upregulated while nNOS levels did not change. The nNOS dimer-to-monomer ratio decreased significantly in DSS- but not in TNBS-induced colitis. No differences were observed in the percentage of either ChAT (31 vs. 33%)- or nNOS (37 vs. 41%)-immunopositive neurons per ganglia or the mean number of neurons per ganglia (55 ± 5 vs. 59 ± 5, P > 0.05). Incubation of the distal colon muscularis externae in vitro with different types of inflammatory mediators showed that cytokines decreased ChAT and nNOS expression, whereas H₂O₂, a component of oxidative stress, increased their expression. NF-κB inhibitor MG-132 did not prevent the IL-1β-induced decline in either ChAT or nNOS expression. These findings showed that TNBS- and DSS-induced inflammation differentially regulates the expression of two critical proteins expressed in the colonic myenteric neurons. These differences are likely due to the exposure of the myenteric plexus neurons to different combinations of Th1-type inflammatory mediators and H₂O₂ in each model.

  7. Paradoxes and Innovation in Family Firms

    DEFF Research Database (Denmark)

    Ingram, Amy E.; Lewis, Marianne W.; Barton, Sid

    2016-01-01

    Scholars stress that family firms are inherently paradoxical, and that tensions, such as tradition versus change, family liquidity versus business growth, and founder control versus successor autonomy, can both inhibit and foster innovation. Further, theorists propose that firms led by paradoxical...... thinkers are more likely to manage these tensions and fuel innovative behavior. Leveraging family business and organizational paradox literatures, this multi-stage exploratory study develops measures of paradoxical tensions and paradoxical thinking in family firms, and tests these propositions. Findings...

  8. Toward the Kelvin’s Formula Paradox

    Science.gov (United States)

    2016-09-01

    According to the Kelvins formula paradox , a polarized body will be accelerated by its own electrostatic or magnetostatic field. This paradoxical ...a general approach allowing to get rid of this paradox . However, the approach leads to quite complex formulae. Needless to say, a simpler resolution...of the paradox , if possible, would be highly desirable. A potentially simpler resolution of the paradox was recently suggested by our colleagues

  9. A Probabilistic Analysis of the Fermi Paradox

    CERN Document Server

    Solomonides, Evan; Terzian, Yervant

    2016-01-01

    The fermi paradox uses an appeal to the mediocrity principle to make it seem counter-intuitive that humanity has not been contacted by extraterrestrial intelligence. A numerical, statistical analysis was conducted to determine whether this apparent loneliness is, in fact, unexpected. An inequality was derived to relate the frequency of life arising and developing technology on a suitable planet in the galaxy, the average length of time since the first broadcast of such a civilization, and a constant term. An analysis of the sphere reached thus far by human communication was also conducted, considering our local neighborhood and planets of particular interest. We clearly show that human communication has not reached a number of stars and planets adequate to expect an answer. These analyses both conclude that the Fermi paradox is not, in fact, unexpected. By the mediocrity principle and numerical modeling, it is actually unlikely that the Earth would have been reached by extraterrestrial communication at this p...

  10. Explaining the harmonic sequence paradox.

    Science.gov (United States)

    Schmidt, Ulrich; Zimper, Alexander

    2012-05-01

    According to the harmonic sequence paradox, an expected utility decision maker's willingness to pay for a gamble whose expected payoffs evolve according to the harmonic series is finite if and only if his marginal utility of additional income becomes zero for rather low payoff levels. Since the assumption of zero marginal utility is implausible for finite payoff levels, expected utility theory - as well as its standard generalizations such as cumulative prospect theory - are apparently unable to explain a finite willingness to pay. This paper presents first an experimental study of the harmonic sequence paradox. Additionally, it demonstrates that the theoretical argument of the harmonic sequence paradox only applies to time-patient decision makers, whereas the paradox is easily avoided if time-impatience is introduced.

  11. Identifying Quantum Structures in the Ellsberg Paradox

    Science.gov (United States)

    Aerts, Diederik; Sozzo, Sandro; Tapia, Jocelyn

    2014-10-01

    Empirical evidence has confirmed that quantum effects occur frequently also outside the microscopic domain, while quantum structures satisfactorily model various situations in several areas of science, including biological, cognitive and social processes. In this paper, we elaborate a quantum mechanical model which faithfully describes the Ellsberg paradox in economics, showing that the mathematical formalism of quantum mechanics is capable to represent the ambiguity present in this kind of situations, because of the presence of contextuality. Then, we analyze the data collected in a concrete experiment we performed on the Ellsberg paradox and work out a complete representation of them in complex Hilbert space. We prove that the presence of quantum structure is genuine, that is, interference and superposition in a complex Hilbert space are really necessary to describe the conceptual situation presented by Ellsberg. Moreover, our approach sheds light on `ambiguity laden' decision processes in economics and decision theory, and allows to deal with different Ellsberg-type generalizations, e.g., the Machina paradox.

  12. Four paradoxes about the special theory of relativity

    CERN Document Server

    Li, Xiao-Jun; Li, Xiao-Niu; Li, Yong-An

    2016-01-01

    Various paradoxes about the relativity theory have been developed since the birth of this theory. Each paradox somewhat shows people's query about the relativity theory, and solving of each paradox demonstrates the correctness of relativity theory once again. In this paper, four paradoxes about the special theory of relativity are brought forward: displacement paradox, electromagnetic transformation paradox, Doppler paradox and magnetic force paradox. We hope some researchers can reasonably explain these paradoxes, and then knowledge of the relativity theory will become more abundant.

  13. The Governance Paradox in Megaprojects

    OpenAIRE

    Arena, Lise; Molloy, Eamonn

    2010-01-01

    This research explores a theoretical and practical paradox in megaprojects. According to transaction cost economics (Williamson, 1975) high uncertainty, high asset specificity, situated knowledge and the high frequency of transactions associated with megaprojects should drive managers to internalise resources. However, evidence from case studies reveals the following paradox: managerial incentives to invest in internal resources through vertical integration are limited because of fixed time h...

  14. Paradoxical therapy in conversion disorder

    OpenAIRE

    ATAOĞLU, Ahmet

    2014-01-01

    Paradoxical therapy consists of suggesting that the patient intentionally engages in the unwanted behaviour, such as performing complusive ritual or bringing on a conversion attack. In this study paradoxical intention (PI) was used with to half of the patients with conversion disorders, while the other half were treated with diazepam in order to examine the efficiency of the PI versus diazepam in conversion disorder. Patients treated with PI appeared to have a greater improvement r...

  15. The abortion paradox.

    Science.gov (United States)

    Bergin, J D

    1983-10-12

    of what has changed to make induced abortions increase markedly in Wellington and in the country. The 1st paradox of abortion is that the more science, the more technical advance, the more clinical skills, yet more induced abortions. There are other paradoxical aspects like the continued surfacing of mental health as a reason for induced abortion when so much psychiatric literature indicates that there are no neurotic or psychotic conditions for which abortion is beneficial. Whether or not the law has been subject to abuse, there has been a change in the handling of abortion by doctors.

  16. Methane excess production in oxygen-rich polar water and a model of cellular conditions for this paradox

    Science.gov (United States)

    Damm, E.; Thoms, S.; Beszczynska-Möller, A.; Nöthig, E. M.; Kattner, G.

    2015-09-01

    Summer sea ice cover in the Arctic Ocean has undergone a reduction in the last decade exposing the sea surface to unforeseen environmental changes. Melting sea ice increases water stratification and induces nutrient limitation, which is also known to play a crucial role in methane formation in oxygenated surface water. We report on an excess of methane in the marginal ice zone in the western Fram Strait. Our study is based on measurements of oxygen, methane, DMSP, nitrate and phosphate concentrations as well as on phytoplankton composition and light transmission, conducted along the 79°N oceanographic transect, in the western part of the Fram Strait and in Northeast Water Polynya region off Greenland. Between the eastern Fram Strait, where Atlantic water enters from the south and the western Fram Strait, where Polar water enters from the north, different nutrient limitations occurred and consequently different bloom conditions were established. Ongoing sea ice melting enhances the environmental differences between both water masses and initiates regenerated production in the western Fram Strait. We show that in this region methane is in situ produced while DMSP (dimethylsulfoniopropionate) released from sea ice may serve as a precursor for the methane formation. The methane production occured despite high oxygen concentrations in this water masses. As the metabolic activity (respiration) of unicellular organisms explains the presence of anaerobic conditions in the cellular environment we present a theoretical model which explains the maintenance of anaerobic conditions for methane formation inside bacterial cells, despite enhanced oxygen concentrations in the environment.

  17. The obesity paradox: is it really a paradox? Hypertension.

    Science.gov (United States)

    Lechi, Alessandro

    2017-03-01

    This article is a narrative overview of the role of hypertension on the relationships between obesity, morbidity, and mortality. We used as sources MEDLINE/PubMed, CINAHL, EMBASE, and Cochrane Library, from inception to March 2016. Key words include overweight, obesity, visceral obesity, obesity paradox, and hypertension. In addition, we hand-searched references from the retrieved articles. This work is one of the works of the topical collection "Obesity Paradox". The positive association between overweight, obesity, and cardiovascular diseases is well established, though this relation is typically U shaped with an increased risk in low-weight subjects or even a beneficial effect of overweight and obesity, the so-called "obesity paradox". In addition, the relationship between obesity and arterial hypertension has been demonstrated in both children and adults by many epidemiological studies. Moreover, weight reduction is followed by a decrease in blood pressure in many patients and ameliorates the cardiovascular risk profile. Recent studies using more appropriate obesity indices raise some doubt about the real significance of obesity paradox and there are several studies that central obesity shows either no protective or even a worse effect. These observations raise the question: what kind of obesity is protective and what kind of obesity is harmful? The studies of obesity paradox suffer from several methodological limitations: most of these are retrospective analyses or were not specifically designed to study obesity paradox as a primary goal; a few studies have data on preceding unintentional weight loss and on some particular confounding variables. In conclusion, more prospective and accurate studies are necessary to better elucidate the clinical importance of obesity paradox. When weight loss is functional to reduce hypertension and cardiovascular risk, it should be encouraged, while an unintentional weight in a patient with chronic diseases may indicate an

  18. Two quantum Simpson's paradoxes

    CERN Document Server

    Paris, Matteo G A

    2012-01-01

    The so-called Simpson's "paradox", or Yule-Simpson (YS) effect, occurs in classical statistics when the correlations that are present among different sets of samples are reversed if the sets are combined together, thus ignoring one or more lurking variables. Here we illustrate the occurrence of two analogue effects in quantum measurements. The first, which we term quantum-classical YS effect, may occur with quantum limited measurements and with lurking variables coming from the mixing of states, whereas the second, here referred to as quantum-quantum YS effect, may take place when coherent superpositions of quantum states are allowed. By analyzing quantum measurements on low dimensional systems (qubits and qutrits), we show that the two effects may occur independently, and that the quantum-quantum YS effect is more likely to occur than the corresponding quantum-classical one. We also found that there exist classes of superposition states for which the quantum-classical YS effect cannot occur for any measureme...

  19. A relativistic trolley paradox

    Science.gov (United States)

    Matvejev, Vadim N.; Matvejev, Oleg V.; Grøn, Ø.

    2016-06-01

    We present an apparent paradox within the special theory of relativity, involving a trolley with relativistic velocity and its rolling wheels. Two solutions are given, both making clear the physical reality of the Lorentz contraction, and that the distance on the rails between each time a specific point on the rim touches the rail is not equal to 2 π R , where R is the radius of the wheel, but 2 π R / √{ 1 - R 2 Ω 2 / c 2 } , where Ω is the angular velocity of the wheels. In one solution, the wheel radius is constant as the velocity of the trolley increases, and in the other the wheels contract in the radial direction. We also explain two surprising facts. First that the shape of a rolling wheel is elliptical in spite of the fact that the upper part of the wheel moves faster than the lower part, and thus is more Lorentz contracted, and second that a Lorentz contracted wheel with relativistic velocity rolls out a larger distance between two successive touches of a point of the wheel on the rails than the length of a circle with the same radius as the wheels.

  20. A Probabilistic Analysis of the Fermi Paradox

    Science.gov (United States)

    Solomonides, Evan; Terzian, Yervant

    2016-06-01

    The Fermi paradox uses an appeal to the mediocrity principle to make it seem counterintuitive that humanity has not been contacted by extraterrestrial intelligence. A numerical, statistical analysis was conducted to determine whether this apparent loneliness is, in fact, unexpected. An inequality was derived to relate the frequency of life arising and developing technology on a suitable planet in the galaxy; the average length of time since the first broadcast of such a civilization; and a constant term. An analysis of the sphere reached thus far by human communication was also conducted, considering our local neighborhood and planets of particular interest. These analyses both conclude that the Fermi paradox is not, in fact, unexpected. By the mediocrity principle and numerical modeling, it is actually unlikely that the Earth would have been reached by extraterrestrial communication at this point. We predict that under 1% of the galaxy has been reached at all thus far, and we do not anticipate to be reached until approximately 50% of stars/planets have been reached. We offer a prediction that we should not expect this until at least 1,500 years in the future. Thus the Fermi paradox is not a shocking observation- or lack thereof- and humanity may very well be contacted within our species’ lifespan (we can begin to expect to be contacted 1,500 years in the future).

  1. The fermi paradox is neither Fermi's nor a paradox.

    Science.gov (United States)

    Gray, Robert H

    2015-03-01

    The so-called Fermi paradox claims that if technological life existed anywhere else, we would see evidence of its visits to Earth--and since we do not, such life does not exist, or some special explanation is needed. Enrico Fermi, however, never published anything on this topic. On the one occasion he is known to have mentioned it, he asked "Where is everybody?"--apparently suggesting that we do not see extraterrestrials on Earth because interstellar travel may not be feasible, but not suggesting that intelligent extraterrestrial life does not exist or suggesting its absence is paradoxical. The claim "they are not here; therefore they do not exist" was first published by Michael Hart, claiming that interstellar travel and colonization of the Galaxy would be inevitable if intelligent extraterrestrial life existed, and taking its absence here as proof that it does not exist anywhere. The Fermi paradox appears to originate in Hart's argument, not Fermi's question. Clarifying the origin of these ideas is important, because the Fermi paradox is seen by some as an authoritative objection to searching for evidence of extraterrestrial intelligence--cited in the U.S. Congress as a reason for killing NASA's SETI program on one occasion. But evidence indicates that it misrepresents Fermi's views, misappropriates his authority, deprives the actual authors of credit, and is not a valid paradox.

  2. [The paradox of motherhood].

    Science.gov (United States)

    Ouaidou, N G

    1990-08-01

    All Sahelian countries are working to define their population policies. A population policy document avoids dispersion and duplication. It opens the path to efficiency. It makes it easier to achieve governmental socioeconomic objectives. Various recent population-related meetings have at least two points in common: they aim to overstep and improve a given situation and are at the same time some examples of implementing the Ndjamena action program, adopted in January 1989. All these population-centered actions return to the problem of adolescent fertility--a poignant problem. Adolescent pregnancy is a major source of family and social break-ups. This paradox of motherhood makes a violent storm burst in the skies ordinarily serene with joy and hope. It is an enemy perverse to economic development and social progress. Adolescent motherhood is a phenomenon which complicates and aggravates population problems and is taboo to the point it is still imperceptible, unknown. It is a problem of premier importance in the Sahel. Pregnancy strikes a woman so very unprepared for motherhood and its demands. It risks the life of a being which is preparing itself to enter the world. Adolescent pregnancy has equally tragic health effects: poorly performed underground abortions and maternal and infant deaths. Adolescent fertility is a burning problem regardless of the perspective (demographic, economic, social, or health). In Sahelian countries, one is beginning to be interested in and to speak about it. It will be necessary to search for solutions. Schools must be a top target for all activities aiming to check adolescent fertility. The emphasis must be on information, education, and responsibility of girls, boys, teachers, and parents. Education and training are of capital importance for socioeconomic development of the Sahel. All activities implemented in the education sector should include a large place for family life education in pregnancy prevention.

  3. The paradox of scientific expertise

    DEFF Research Database (Denmark)

    Alrøe, Hugo Fjelsted; Noe, Egon

    2011-01-01

    Modern societies depend on a growing production of scientific knowledge, which is based on the functional differentiation of science into still more specialised scientific disciplines and subdisciplines. This is the basis for the paradox of scientific expertise: The growth of science leads to a f...... cross-disciplinary research and in the collective use of different kinds of scientific expertise, and thereby make society better able to solve complex, real-world problems.......Modern societies depend on a growing production of scientific knowledge, which is based on the functional differentiation of science into still more specialised scientific disciplines and subdisciplines. This is the basis for the paradox of scientific expertise: The growth of science leads...... to a fragmentation of scientific expertise. To resolve this paradox, the present paper investigates three hypotheses: 1) All scientific knowledge is perspectival. 2) The perspectival structure of science leads to specific forms of knowledge asymmetries. 3) Such perspectival knowledge asymmetries must be handled...

  4. Teaching Quantum Physics without Paradoxes

    Science.gov (United States)

    Hobson, Art

    2007-01-01

    Although the resolution to the wave-particle paradox has been known for 80 years, it is seldom presented. Briefly, the resolution is that material particles and photons are the quanta of extended spatially continuous but energetically quantized fields. But because the resolution resides in quantum field theory and is not usually spelled out in…

  5. Mechanical Paradox: The Uphill Roller

    Science.gov (United States)

    Cortes, Emilio; Cortes-Poza, D.

    2011-01-01

    We analyse in detail the dynamics of a mechanical system which is a rigid body with the geometry of a double cone. This double cone is apparently able to spontaneously roll uphill along inclined rails. The experiment has been known for some centuries, and because of its peculiar behaviour, it has been named "mechanical paradox". Although this…

  6. Teaching Quantum Physics without Paradoxes

    Science.gov (United States)

    Hobson, Art

    2007-01-01

    Although the resolution to the wave-particle paradox has been known for 80 years, it is seldom presented. Briefly, the resolution is that material particles and photons are the quanta of extended spatially continuous but energetically quantized fields. But because the resolution resides in quantum field theory and is not usually spelled out in…

  7. The Banach-Tarski paradox

    CERN Document Server

    Wagon, Stan

    1985-01-01

    The Banach-Tarski paradox is a most striking mathematical construction: it asserts that a solid ball may be taken apart into finitely many pieces that can be rearranged using rigid motions to form a ball twice as large as the original. This volume explore

  8. The Paradox of Painful Art

    Science.gov (United States)

    Smuts, Aaron

    2007-01-01

    Many of the most popular genres of narrative art are designed to elicit negative emotions: emotions that are experienced as painful or involving some degree of pain, which people generally avoid in their daily lives. Traditionally, the question of why people seek out such experiences of painful art has been presented as the paradox of tragedy, and…

  9. Generalized friendship paradox in networks with tunable degree-attribute correlation

    CERN Document Server

    Jo, Hang-Hyun

    2014-01-01

    One of interesting phenomena due to topological heterogeneities in complex networks is the friendship paradox: Your friends have on average more friends than you do. Recently, this paradox has been generalized for arbitrary node attributes, called generalized friendship paradox (GFP). The origin of GFP at the network level has been shown to be rooted in positive correlations between degrees and attributes. However, how the GFP holds for individual nodes needs to be understood in more detail. For this, we first analyze a solvable model to characterize the paradox holding probability of nodes for the uncorrelated case. Then we numerically study the correlated model of networks with tunable degree-degree and degree-attribute correlations. In contrast to the network level, we find at the individual level that the relevance of degree-attribute correlation to the paradox holding probability may depend on whether the network is assortative or dissortative. These findings help us to understand the interplay between t...

  10. Parrondo's Paradox: some new results and new ideas

    CERN Document Server

    Gupta, Abhijit Kar

    2016-01-01

    Parrondo's paradox is about a paradoxical game and gambling where two probabilistic losing games can be combined to form a winning game. While the counter intuitive game is interesting in itself, it can be thought of a discrete version of Brownian flashing ratchet which are employed to understand noise induced order. There are plenty of examples from physics to biology and social sciences where the stochastic thermal fluctuations actually help achieving positive movements. In our study, we study various combinations of losing games in order to understand how and how far the losing combinations result in winning. Further we devise an alternative model to study the similar paradox. The work reported here is mostly done through computer simulations.

  11. The Fermi Paradox is Neither Fermis Nor a Paradox

    CERN Document Server

    Gray, Robert H

    2016-01-01

    The so-called Fermi paradox claims that if technological life existed anywhere else, we would see evidence of its visits to Earth-and since we do not, such life does not exist, or some special explanation is needed. Enrico Fermi, however, never published anything on this topic. On the one occasion he is known to have mentioned it, he asked 'where is everybody?'- apparently suggesting that we don't see extraterrestrials on Earth because interstellar travel may not be feasible, but not suggesting that intelligent extraterrestrial life does not exist, or suggesting its absence is paradoxical. The claim 'they are not here; therefore they do not exist' was first published by Michael Hart, claiming that interstellar travel and colonization of the galaxy would be inevitable if intelligent extraterrestrial life existed, and taking its absence here as proof that it does not exist anywhere. The Fermi paradox appears to originate in Hart's argument, not Fermi's question. Clarifying the origin of these ideas is important...

  12. The Double Cone: A Mechanical Paradox or a Geometrical Constraint?

    Science.gov (United States)

    Gallitto, Aurelio Agliolo; Fiordilino, Emilio

    2011-01-01

    In the framework of the Italian National Plan "Lauree Scientifiche" (PLS) in collaboration with secondary schools, we have investigated the mechanical paradox of the double cone. We have calculated the geometric condition for obtaining an upward movement. Based on this result, we have built a mechanical model with a double cone made of aluminum…

  13. The Double Cone: A Mechanical Paradox or a Geometrical Constraint?

    Science.gov (United States)

    Gallitto, Aurelio Agliolo; Fiordilino, Emilio

    2011-01-01

    In the framework of the Italian National Plan "Lauree Scientifiche" (PLS) in collaboration with secondary schools, we have investigated the mechanical paradox of the double cone. We have calculated the geometric condition for obtaining an upward movement. Based on this result, we have built a mechanical model with a double cone made of aluminum…

  14. Sweet Dream Liquid Chinese Medicine Ameliorates Learning and Memory Deficit in a Rat Model of Paradoxical Sleep Deprivation through the ERK/CREB Signaling Pathway.

    Science.gov (United States)

    Su, Xinyun; Wang, Chunhua; Wang, Xiuhua; Han, Fang; Lv, Changjun; Zhang, Xiuli

    2016-05-01

    Sweet dream oral liquid (SDOL), a traditional Chinese herbal compound contains 17 traditional Chinese medicines. It has various pharmacological effects, such as improving brain dysfunction and increasing sleeping quality. This study investigated the neuroprotective effect and the underlying mechanisms of SDOL-impaired hippocampus learning and memory-induced paradoxical sleep deprivation (PSD) in rats. Sixty Male Wistar rats were randomly divided into six groups. Before PSD, SDOL treatment group rats were intragastrically administered SDOL for 25 days at dose of 2.1, 4.2, and 8.4 mL/kg body weight per day. Normal control group, large platform control group, and PSD groups were treated with normal saline instead of SDOL. After 25 days treatment, PSD and SDOL groups were deprived of paradoxical sleep for 72 h. Then two behavioral studies were conducted to test the spatial learning and memory ability using the open field test and Morris water maze test. Expression of the c-fos, c-jun, cyclic AMP response element binding protein (CREB), extracellular signal-regulated protein kinase (ERK), mitogen-activated protein kinases (MAPK)/ERK kinase (MEK), and p-CREB, p-ERK, and p-MEK in the hippocampus were also assayed by western blot. In this study, PSD decreased the levels of p-CREB, p-ERK, p-MEK, c-fos, and c-jun. However, SDOL treatment increased expressions of these proteins. Our results showed that SDOL improved 72-h PSD-induced cognitive impairment. These affects may be mediated by increasing the contents of c-fos, c-jun, and p-CREB/ERK signaling.

  15. Measurements, disturbances and the quantum three box paradox

    Science.gov (United States)

    Maroney, O. J. E.

    2017-05-01

    A quantum pre- and post-selection paradox involves making measurements at two separate times on a quantum system, and making inferences about the state of the system at an intermediate time, conditional upon the observed outcomes. The inferences lead to predictions about the results of measurements performed at the intermediate time, which have been well confirmed experimentally, but which nevertheless seem paradoxical when inferences about different intermediate measurements are combined. The three box paradox is the paradigm example of such an effect, where a ball is placed in one of three boxes and is shuffled between the boxes in between two measurements of its location. By conditionalising on the outcomes of those measurements, it is inferred that between the two measurements the ball would have been found with certainty in Box 1 and with certainty in Box 2, if either box been opened on their own. Despite experimental confirmation of the predictions, and much discussion, it has remained unclear what exactly is supposed to be paradoxical or what specifically is supposed to be quantum, about these effects. In this paper I identify precisely the conditions under which the quantum three box paradox occurs, and show that these conditions are the same as arise in the derivation of the Leggett-Garg Inequality, which is supposed to demonstrate the incompatibility of quantum theory with macroscopic realism. I will argue that, as in Leggett-Garg Inequality violations, the source of the effect actually lies in the disturbance introduced by the intermediate measurement, and that the quantum nature of the effect is that no classical model of measurement disturbance can reproduce the paradox.

  16. Renal cell carcinoma survival and body mass index: a dose-response meta-analysis reveals another potential paradox within a paradox.

    Science.gov (United States)

    Bagheri, M; Speakman, J R; Shemirani, F; Djafarian, K

    2016-12-01

    In healthy subjects increasing body mass index (BMI) leads to greater mortality from a range of causes. Following onset of specific diseases, however, the reverse is often found: called the 'obesity paradox'. But we recently observed the phenomenon called the 'paradox within the paradox' for stroke patients. The objective of our study was to examine the effect of each unit increase in BMI on renal cancer-specific survival (CSS), cancer-specific mortality, overall survival (OS) and overall mortality. Random-effects generalized least squares models for trend estimation were used to analyze the data. Eight studies, comprising of 8699 survivals of 10 512 renal cell carcinoma (RCC) patients met the inclusion criteria, including 5 on CSS and 3 on OS. The association of BMI with CSS and OS was non-linear (Pparadox in RCC. However, each unit increase in BMI over 25 was associated with decreased OS, indicating that RCC may also exhibit a paradox within the paradox. Inconsistent effects of increases in BMI on CSS and OS, as previously observed for stroke, creates a paradox (different directions of mortality for different causes) within the obesity paradox.

  17. The paradox of scientific expertise

    DEFF Research Database (Denmark)

    Alrøe, Hugo Fjelsted; Noe, Egon

    2011-01-01

    to a fragmentation of scientific expertise. To resolve this paradox, the present paper investigates three hypotheses: 1) All scientific knowledge is perspectival. 2) The perspectival structure of science leads to specific forms of knowledge asymmetries. 3) Such perspectival knowledge asymmetries must be handled......Modern societies depend on a growing production of scientific knowledge, which is based on the functional differentiation of science into still more specialised scientific disciplines and subdisciplines. This is the basis for the paradox of scientific expertise: The growth of science leads...... through second order perspectives. We substantiate these hypotheses on the basis of a perspectivist philosophy of science grounded in Peircean semiotics and autopoietic systems theory. Perspectival knowledge asymmetries are an unavoidable and necessary part of the growth of scientific knowledge, and more...

  18. The obesity paradox in diabetes.

    Science.gov (United States)

    Carnethon, Mercedes R; Rasmussen-Torvik, Laura J; Palaniappan, Latha

    2014-02-01

    Overweight or obese adults have demonstrated a survival advantage compared with leaner adults in several population-based samples. This counterintuitive association has been termed the obesity paradox. Evidence for an obesity paradox among persons with diabetes has been less consistent. In the present review, we identified 18 longitudinal studies conducted in cohort studies, patient registries and clinical trial populations that tested the associations between obesity and survival in patients with diabetes. The majority of these studies reported that mortality was lowest in overweight and obese persons, and that leaner adults had the highest relative total and cardiovascular mortality. Some of these studies observed the patterns most strongly in older (age > 65 years) adults. To date, little research has been conducted to identify mechanisms that could explain elevated mortality in leaner adults with diabetes, or to identify strategies for diabetes management or mitigation of elevated mortality risk.

  19. Quantum Structure in Economics: The Ellsberg Paradox

    CERN Document Server

    Aerts, Diederik; 10.1063/1.3689001

    2013-01-01

    The 'expected utility hypothesis' and 'Savage's Sure-Thing Principle' are violated in real life decisions, as shown by the 'Allais' and 'Ellsberg paradoxes'. The popular explanation in terms of 'ambiguity aversion' is not completely accepted. As a consequence, uncertainty is still problematical in economics. To overcome these difficulties a distinction between 'risk' and 'ambiguity' has been introduced which depends on the existence of a Kolmogorovian probabilistic structure modeling these uncertainties. On the other hand, evidence of everyday life suggests that context plays a fundamental role in human decisions under uncertainty. Moreover, it is well known from physics that any probabilistic structure modeling contextual interactions between entities structurally needs a non-Kolmogorovian framework admitting a quantum-like representation. For this reason, we have recently introduced a notion of 'contextual risk' to mathematically capture situations in which ambiguity occurs. We prove in this paper that the ...

  20. Economic globalisation and paradoxes

    Directory of Open Access Journals (Sweden)

    Dokmanović Mirjana

    2003-01-01

    Full Text Available The increased development of technology and integration of markets have created possibilities to eradicate hunger, poverty and other illnesses of the mankind. Contrary, the world is facing opposite trends: the widening gap between the rich and the poor, increasing poverty, human security and conflicts. The negative effects of the globalisation that experience the majority of the world population are rooted at the ruling neoliberal model of macro economy, shaped and dictated by the international financial institutions, WTO, multilateral companies and transnational corporations. This logic is based on the free market economy, free flow of capital, resources, investments and labour force, trade liberalisation, deregulation, privatisation, reduction of social services, and elimination of the concept of “the public good”. This economic model induces exploitation, discrimination, and inequalities, and therefore, it suits only to the big and powerful (states, markets, companies, individuals..., while brings disadvantages to the small and less powerful (states, markets, companies, individuals.... In addition, it deepens historical and contemporary inequalities based on race, sex, ethnicity, nationality etc. between and within states, and regions, including the West and the North. This context of development especially hurts vulnerable and marginalised groups, including women, resulting in their social exclusion and increased poverty. The efforts regarding the realisation of the UN Millennium Development Goals, including eradication of poverty and hunger, and development of gender equity, will be not effective at all until the neoliberal model should be replaced by the heliocentric, human rights approach to development.

  1. Second Parrondo's Paradox in Scale Free Networks

    CERN Document Server

    Toyota, Norihito

    2012-01-01

    Parrondo's paradox occurs in sequences of games in which a winning expectation value of a payoff may be obtained by playing two games in a random order, even though each game in the sequence may be lost when played individually.Several variations of Parrondo's games apparently with the same paradoxical property have been introduced by G.P. Harmer and D. Abbott; history dependence, one dimensional line, two dimensional lattice and so on. I have shown that Parrondo's paradox does not occur in scale free networks in the simplest case with the same number of parameters as the original Parrondo's paradox. It suggests that some technical complexities are needed to present Parrondo's paradox in scale free networks. In this article, I show that a simple modification with the same number of parameters as the original Parrondo's paradox creates Parrondo's paradox in scale free. This paradox is, however, created by a quite different mechanism from the original Parrondo's paradox and a considerably rare phenomenon, where...

  2. The practical paradox of technology: The influence of communication technology use on employee burnout and engagement

    NARCIS (Netherlands)

    ter Hoeven, C.L.; van Zoonen, W.; Fonner, K.L.

    2016-01-01

    Technological advancements in the workplace frequently have produced contradictory effects by facilitating accessibility and efficiency while increasing interruptions and unpredictability. We combine insights from organizational paradoxes and the job demands–resources model to construct a framework

  3. Alterations at the cross-bridge level are associated with a paradoxical gain of muscle function in vivo in a mouse model of nemaline myopathy.

    Science.gov (United States)

    Gineste, Charlotte; Ottenheijm, Coen; Le Fur, Yann; Banzet, Sébastien; Pecchi, Emilie; Vilmen, Christophe; Cozzone, Patrick J; Koulmann, Nathalie; Hardeman, Edna C; Bendahan, David; Gondin, Julien

    2014-01-01

    Nemaline myopathy is the most common disease entity among non-dystrophic skeletal muscle congenital diseases. The first disease causing mutation (Met9Arg) was identified in the gene encoding α-tropomyosin slow gene (TPM3). Considering the conflicting findings of the previous studies on the transgenic (Tg) mice carrying the TPM3Met9Arg mutation, we investigated carefully the effect of the Met9Arg mutation in 8-9 month-old Tg(TPM3)Met9Arg mice on muscle function using a multiscale methodological approach including skinned muscle fibers analysis and in vivo investigations by magnetic resonance imaging and 31-phosphorus magnetic resonance spectroscopy. While in vitro maximal force production was reduced in Tg(TPM3)Met9Arg mice as compared to controls, in vivo measurements revealed an improved mechanical performance in the transgenic mice as compared to the former. The reduced in vitro muscle force might be related to alterations occurring at the cross-bridges level with muscle-specific underlying mechanisms. In vivo muscle improvement was not associated with any changes in either muscle volume or energy metabolism. Our findings indicate that TPM3(Met9Arg) mutation leads to a mild muscle weakness in vitro related to an alteration at the cross-bridges level and a paradoxical gain of muscle function in vivo. These results clearly point out that in vitro alterations are muscle-dependent and do not necessarily translate into similar changes in vivo.

  4. Alterations at the cross-bridge level are associated with a paradoxical gain of muscle function in vivo in a mouse model of nemaline myopathy.

    Directory of Open Access Journals (Sweden)

    Charlotte Gineste

    Full Text Available Nemaline myopathy is the most common disease entity among non-dystrophic skeletal muscle congenital diseases. The first disease causing mutation (Met9Arg was identified in the gene encoding α-tropomyosin slow gene (TPM3. Considering the conflicting findings of the previous studies on the transgenic (Tg mice carrying the TPM3Met9Arg mutation, we investigated carefully the effect of the Met9Arg mutation in 8-9 month-old Tg(TPM3Met9Arg mice on muscle function using a multiscale methodological approach including skinned muscle fibers analysis and in vivo investigations by magnetic resonance imaging and 31-phosphorus magnetic resonance spectroscopy. While in vitro maximal force production was reduced in Tg(TPM3Met9Arg mice as compared to controls, in vivo measurements revealed an improved mechanical performance in the transgenic mice as compared to the former. The reduced in vitro muscle force might be related to alterations occurring at the cross-bridges level with muscle-specific underlying mechanisms. In vivo muscle improvement was not associated with any changes in either muscle volume or energy metabolism. Our findings indicate that TPM3(Met9Arg mutation leads to a mild muscle weakness in vitro related to an alteration at the cross-bridges level and a paradoxical gain of muscle function in vivo. These results clearly point out that in vitro alterations are muscle-dependent and do not necessarily translate into similar changes in vivo.

  5. The Banach-Tarski paradox for flag manifolds

    CERN Document Server

    Komori, Yohei

    2011-01-01

    The famous Banach-Tarski paradox claims that the three dimensional rotation group acts on the two dimensional sphere paradoxically. In this paper, we generalize their result to show that the classical group acts on the flag manifold paradoxically.

  6. Scrounging by foragers can resolve the paradox of enrichment.

    Science.gov (United States)

    Toyokawa, Wataru

    2017-03-01

    Theoretical models of predator-prey systems predict that sufficient enrichment of prey can generate large amplitude limit cycles, paradoxically causing a high risk of extinction (the paradox of enrichment). Although real ecological communities contain many gregarious species, whose foraging behaviour should be influenced by socially transmitted information, few theoretical studies have examined the possibility that social foraging might resolve this paradox. I considered a predator population in which individuals play the producer-scrounger foraging game in one-prey-one-predator and two-prey-one-predator systems. I analysed the stability of a coexisting equilibrium point in the one-prey system and that of non-equilibrium dynamics in the two-prey system. The results revealed that social foraging could stabilize both systems, and thereby resolve the paradox of enrichment when scrounging behaviour (i.e. kleptoparasitism) is prevalent in predators. This suggests a previously neglected mechanism underlying a powerful effect of group-living animals on the sustainability of ecological communities.

  7. MCM Paradox: Abundance of Eukaryotic Replicative Helicases and Genomic Integrity

    Directory of Open Access Journals (Sweden)

    Mitali Das

    2014-01-01

    Full Text Available As a crucial component of DNA replication licensing system, minichromosome maintenance (MCM 2–7 complex acts as the eukaryotic DNA replicative helicase. The six related MCM proteins form a heterohexamer and bind with ORC, CDC6, and Cdt1 to form the prereplication complex. Although the MCMs are well known as replicative helicases, their overabundance and distribution patterns on chromatin present a paradox called the “MCM paradox.” Several approaches had been taken to solve the MCM paradox and describe the purpose of excess MCMs distributed beyond the replication origins. Alternative functions of these MCMs rather than a helicase had also been proposed. This review focuses on several models and concepts generated to solve the MCM paradox coinciding with their helicase function and provides insight into the concept that excess MCMs are meant for licensing dormant origins as a backup during replication stress. Finally, we extend our view towards the effect of alteration of MCM level. Though an excess MCM constituent is needed for normal cells to withstand stress, there must be a delineation of the threshold level in normal and malignant cells. This review also outlooks the future prospects to better understand the MCM biology.

  8. Price Paradox and Strategic Choice of "Vegetable Basket" in China

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    By using the analysis method of game theory,this paper analyzes the phenomenon of price paradox of "vegetable basket" in China and its reason as follows:the price paradox of "vegetable basket" in China is that if the vegetable is cheap,it will harm farmers,and if the vegetable is expensive,it will harm people;high-cost logistics,low negotiation status of vegetable growers and cooperation predicament are responsible for price paradox.Based on the theoretical basis of strategic choice-theory of intermediaries,it indicates that the intermediaries can realize effective transaction and save transaction cost.The strategic choice of solving price paradox of "vegetable basket" is put forward as follows:support vegetable growers’ cooperatives,reduce transaction cost and raise the negotiation status of vegetable growers;develop the model of connection of agricultural products and supermarkets,and reduce the cost of transport and distribution;innovate upon intermediaries and develop the third-party logistics.

  9. Unravelling migrants' health paradoxes: a transdisciplinary research agenda.

    Science.gov (United States)

    Roura, Maria

    2017-07-24

    The Social Determinants of Health literature has consistently found that a higher socioeconomic status is associated with better health outcomes even after adjusting for traditional risk factors. However, research findings in the field of Migrants' Health suggest that the socioeconomic/health gradient does not always behave as expected for migrants and their descendants. The mismatch of findings in these two long-standing parallel research traditions is exemplified by frequent reports of paradoxical findings in the scientific literature: the healthy migrant paradox, the ethnic density paradox and the diminishing returns paradox. This paper outlines a transdisciplinary research agenda to elucidate the social processes that underpin these disconcerting findings and calls for a shift from a pathogenic deficit model that sees migrants as a burden to their reconceptualisation as actively engaged citizens in search of solutions. Amidst a severe refugee crisis, fears of terrorist attacks and political capitalisation of these tragedies to foster antimigrant sentiments, this is urgently needed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. MCM Paradox: Abundance of Eukaryotic Replicative Helicases and Genomic Integrity.

    Science.gov (United States)

    Das, Mitali; Singh, Sunita; Pradhan, Satyajit; Narayan, Gopeshwar

    2014-01-01

    As a crucial component of DNA replication licensing system, minichromosome maintenance (MCM) 2-7 complex acts as the eukaryotic DNA replicative helicase. The six related MCM proteins form a heterohexamer and bind with ORC, CDC6, and Cdt1 to form the prereplication complex. Although the MCMs are well known as replicative helicases, their overabundance and distribution patterns on chromatin present a paradox called the "MCM paradox." Several approaches had been taken to solve the MCM paradox and describe the purpose of excess MCMs distributed beyond the replication origins. Alternative functions of these MCMs rather than a helicase had also been proposed. This review focuses on several models and concepts generated to solve the MCM paradox coinciding with their helicase function and provides insight into the concept that excess MCMs are meant for licensing dormant origins as a backup during replication stress. Finally, we extend our view towards the effect of alteration of MCM level. Though an excess MCM constituent is needed for normal cells to withstand stress, there must be a delineation of the threshold level in normal and malignant cells. This review also outlooks the future prospects to better understand the MCM biology.

  11. Stationary bubbles: information loss paradox?

    CERN Document Server

    Domènech, Guillem

    2016-01-01

    The main purpose of this work is to build classically stationary bubbles, within the thin-shell formalism, which are unstable under quantum effects; they either collapse into a black hole or expand. Thus, the final state can be thought of a superposition of geometries. We point out that, from a quantum mechanical point of view, there is no issue with a loss of information in such configuration. A classical observer sees a definite geometry and, hence, finds an effective loss of information. Although it does not cover all possible cases, we emphasise the role of semi-classical gravitational effects, mediated by instatons, in alleviating/solving the information loss paradox.

  12. Bioterrorism and the Fermi Paradox

    Science.gov (United States)

    Cooper, Joshua

    2013-04-01

    We proffer a contemporary solution to the so-called Fermi Paradox, which is concerned with conflict between Copernicanism and the apparent paucity of evidence for intelligent alien civilizations. In particular, we argue that every community of organisms that reaches its space-faring age will (1) almost immediately use its rocket-building computers to reverse-engineer its genetic chemistry and (2) self-destruct when some individual uses said technology to design an omnicidal pathogen. We discuss some of the possible approaches to prevention with regard to Homo sapiens' vulnerability to bioterrorism, particularly on a short-term basis.

  13. A Note on Faraday Paradoxes

    CERN Document Server

    Auchmann, Bernhard; Russenschuck, Stephan

    2014-01-01

    The validity of the flux rule to determine the electromotive force in a cycle, epsilon = -d Phi/dt, has been the subject of a large amount of controversy since the beginning of electrical technology. Although most authors reach correct conclusions for a class of problems called Faraday paradoxes, the arguments that are used vary and often rely on ad-hoc physical reasoning. A didactic and insightful treatment should be based solely on Maxwell's equations, the constitutive laws, and a detailed study of the mathematics involved.

  14. Yule-Simpson's Paradox in Research

    Science.gov (United States)

    Goltz, Heather Honore; Smith, Matthew Lee

    2010-01-01

    Yule (1903) and Simpson (1951) described a statistical paradox that occurs when data is aggregated. In such situations, aggregated data may reveal a trend that directly contrasts those of sub-groups trends. In fact, the aggregate data trends may even be opposite in direction of sub-group trends. To reveal Yule-Simpson's paradox (YSP)-type…

  15. A Krein Quantization Approach to Klein Paradox

    CERN Document Server

    Payandeh, Farrin; Fathi, Mohsen; Moghaddam, Zahra Gh

    2013-01-01

    In this paper we first introduce the famous Klein paradox. Afterwards by proposing the Krein quantization approach and taking the negative modes into account, we will show that the expected and exact current densities, could be achieved without confronting any paradox.

  16. Fundamental quantal paradox and its resolution

    Science.gov (United States)

    Lev, Felix M.

    2017-05-01

    The postulate that coordinate and momentum representations are related to each other by the Fourier transform has been accepted from the beginning of quantum theory. As a consequence, coordinate wave functions of photons emitted by stars have cosmic sizes. This results in a paradox because predictions of the theory contradict observations. The reason of the paradox and its resolution are discussed.

  17. Family Fathers Lost in Theatre Paradox

    DEFF Research Database (Denmark)

    Kuhlmann, Annelis

    2008-01-01

    Diderot's influence on theatre is well known through The Paradox of Acting (Paradoxe sur le comédien). However, Diderot also wrote a few drames bourgeois, among which is The Family Father (Le Père de famille), which still in Diderot's days was edited in Copenhagen in French, and which in Danish...

  18. Virtue Acquisition: The Paradox of Striving

    Science.gov (United States)

    Snow, Nancy

    2016-01-01

    Aristotelian-inspired accounts of virtue acquisition stress guided practice and habituated action to develop virtue. This emphasis on action can lead to the "paradox of striving". The paradox occurs when we try too hard to act well and thereby spoil our efforts. I identify four forms of striving--forcing, impulsivity, overthinking, and…

  19. Quantum Zeno and anti-Zeno paradoxes

    Indian Academy of Sciences (India)

    S M Roy

    2001-02-01

    Continuous observation of a time independent projection operator is known to prevent change of state (the quantum Zeno paradox). We discuss the recent result that generic continuous measurement of time dependent projection operators will in fact ensure change of state: an anti-Zeno paradox.

  20. [Five paradoxes in health promotion].

    Science.gov (United States)

    López-Dicastillo, Olga; Canga-Armayor, Navidad; Mujika, Agurtzane; Pardavila-Belio, Miren Idoia; Belintxon, Maider; Serrano-Monzó, Inmaculada; Pumar-Méndez, María J

    2017-02-17

    The World Health Organization states that health promotion is a key strategy to improve health, and it is conceived as a global process of enabling people to increase control over, and to improve, their health. Health promotion does not focus solely on empowering individuals dealing with their knowledge, attitudes and skills, but it also takes political, social, economic and environmental aspects influencing health and wellbeing into account. The complexity of applying these concepts is reflected in the five paradoxes in health promotion; these arise in between the rhetoric in health promotion and implementation. The detected paradoxes which are described herein involve the patient versus the person, the individual versus the group, disease professionals versus health professionals, disease indicators versus health indicators, and health as an expense versus health as an investment. Making these contradictions explicit can help determine why it is so complex to put the concepts related to health promotion into practice. It can also help to put forward aspects that need further work if health promotion is to put into practice.

  1. An Approach to Resolving Two Paradoxes in Probability Theory

    Institute of Scientific and Technical Information of China (English)

    LIU Dao-jian; HUANG Tian-min; CHEN Ya-bo

    2008-01-01

    A new mathematical expectation formula with some hypotheses, notions and propositions was givento get rid of the challenge of St. Petersburg paradox and Pascal's wager. Relevant results show that it is veryeffective to apply the model to solve the expected revenue problems containing random events with low proba-bility but high revenue. This work also provides the probability theory with a more widely applied perspectivein group decision-making.

  2. The paradox of atheoretical classification

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2016-01-01

    A distinction can be made between “artificial classifications” and “natural classifications,” where artificial classifications may adequately serve some limited purposes, but natural classifications are overall most fruitful by allowing inference and thus many different purposes. There is strong...... support for the view that a natural classification should be based on a theory (and, of course, that the most fruitful theory provides the most fruitful classification). Nevertheless, atheoretical (or “descriptive”) classifications are often produced. Paradoxically, atheoretical classifications may...... be very successful. The best example of a successful “atheoretical” classification is probably the prestigious Diagnostic and Statistical Manual of Mental Disorders (DSM) since its third edition from 1980. Based on such successes one may ask: Should the claim that classifications ideally are natural...

  3. Paradoxical ratcheting in cornstarch suspensions

    Science.gov (United States)

    Shinbrot, Troy; Siu, Theo; Rutala, Matthew

    2014-11-01

    Cornstarch suspensions are well known to exhibit strong shear thickening, and we show as a result that they must - and do - climb vertically vibrating rods and plates. This occurs because when the rod moves upward, it shears the suspension against gravity, and so the fluid stiffens, but when the rod moves downward, the suspension moves with gravity, and so the fluid is more compliant. This causes the fluid to be dragged up by the upstroke more than it is dragged down by the downstroke, effectively ratcheting the fluid up the rod every cycle. We show experimentally and computationally that this effect is paradoxically caused by gravity - and so goes away when gravity is removed - and we show that the suspension can be made to balance on the uphill side of an inclined rod in an analog of the inverted ``Kapitza pendulum,'' closely related to the recent report by Ramachandran & Nosonovsky, Soft Matter 10, 4633 (2014).

  4. The moving plate capacitor paradox

    Science.gov (United States)

    Davis, B. R.; Abbott, D.; Parrondo, J. M. R.

    2000-03-01

    For the first time we describe an apparent paradox concerning a moving plate capacitor driven by thermal noise from a resistor. A demon restores the plates of the capacitor to their original position, only when the voltage across the capacitor is small—hence only small forces are present for the demon to work against. The demon has to work harder than this to avoid the situation of perpetual motion, but the question is how? We explore the concept of a moving plate capacitor, driven by noise, a step further by examining the case where the restoring force on the capacitor plates is provided by a simple spring, rather than some unknown demon. We display simulation results with interesting behavior, particularly where the capacitor plates collide with each other.

  5. The paradox of cooperation benefits.

    Science.gov (United States)

    Németh, A; Takács, K

    2010-05-21

    It seems obvious that as the benefits of cooperation increase, the share of cooperators in the population should also increase. It is well known that positive assortment between cooperative types, for instance in spatially structured populations, provide better conditions for the evolution of cooperation than complete mixing. This study demonstrates that, assuming positive assortment, under most conditions higher cooperation benefits also increase the share of cooperators. On the other hand, under a specified range of payoff values, when at least two payoff parameters are modified, the reverse is true. The conditions for this paradox are determined for two-person social dilemmas: the Prisoner's Dilemma, the Hawks and Doves game, and the Stag Hunt game, assuming global selection and positive assortment.

  6. Gibbs Paradox and Similarity Principle

    CERN Document Server

    Lin, Shu-Kun

    2008-01-01

    Adding -lnN! term to the accepted entropy formula will immediately make the entropy function nonadditive and sometimes negative. As no heat effect and mechanical work are observed, we have a simple experimental resolution of the Gibbs paradox: the thermodynamic entropy of mixing is always zero and the Gibbs free energy change is also always zero during the formation of any ideal mixture of gases, liquids, solids or solutions, whether their components are different or identical. However, information loss is observed and must be the exclusive driving force of these spontaneous processes. Information is defined and calculated as the amount of the compressed data. Information losses due to dynamic motion and static symmetric structure formation are defined as two kinds of entropies-dynamic entropy and static entropy, respectively. Entropy is defined and calculated as the logarithm of the symmetry number. There are three laws of information theory, where the first and the second laws are analogs of the two thermod...

  7. Implications of Stein's Paradox for Environmental Standard Compliance Assessment.

    Science.gov (United States)

    Qian, Song S; Stow, Craig A; Cha, YoonKyung

    2015-05-19

    The implications of Stein's paradox stirred considerable debate in statistical circles when the concept was first introduced in the 1950s. The paradox arises when we are interested in estimating the means of several variables simultaneously. In this situation, the best estimator for an individual mean, the sample average, is no longer the best. Rather, a shrinkage estimator, which shrinks individual sample averages toward the overall average is shown to have improved overall accuracy. Although controversial at the time, the concept of shrinking toward overall average is now widely accepted as a good practice for improving statistical stability and reducing error, not only in simple estimation problems, but also in complicated modeling problems. However, the utility of Stein's insights are not widely recognized in the environmental management community, where mean pollutant concentrations of multiple waters are routinely estimated for management decision-making. In this essay, we introduce Stein's paradox and its modern generalization, the Bayesian hierarchical model, in the context of environmental standard compliance assessment. Using simulated data and nutrient monitoring data from wadeable streams around the Great Lakes, we show that a Bayesian hierarchical model can improve overall estimation accuracy, thereby improving our confidence in the assessment results, especially for standard compliance assessment of waters with small sample sizes.

  8. Why the prevention paradox is a paradox, and why we should solve it: a philosophical view.

    Science.gov (United States)

    John, Stephen

    2011-10-01

    This paper provides some philosophical comments on Rose's prevention paradox, suggesting why that paradox seems so difficult, and why policy-makers should care about solving it. The assumptions underlying the paradox section sets out two ways of understanding the notion of "benefit" in public health programmes, and shows how the prevention paradox arises from combining both understandings. Thinking through the paradox section argues that if we find the second understanding of benefit appealing, then we should rethink how we typically assess preventive public health measures. The implications section shows how these theoretical arguments imply that public health practitioners should care about solving the prevention paradox, rather than simply denying the legitimacy of one of the two views from which it arises. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. How river rocks round: resolving the shape-size paradox.

    Directory of Open Access Journals (Sweden)

    Gabor Domokos

    Full Text Available River-bed sediments display two universal downstream trends: fining, in which particle size decreases; and rounding, where pebble shapes evolve toward ellipsoids. Rounding is known to result from transport-induced abrasion; however many researchers argue that the contribution of abrasion to downstream fining is negligible. This presents a paradox: downstream shape change indicates substantial abrasion, while size change apparently rules it out. Here we use laboratory experiments and numerical modeling to show quantitatively that pebble abrasion is a curvature-driven flow problem. As a consequence, abrasion occurs in two well-separated phases: first, pebble edges rapidly round without any change in axis dimensions until the shape becomes entirely convex; and second, axis dimensions are then slowly reduced while the particle remains convex. Explicit study of pebble shape evolution helps resolve the shape-size paradox by reconciling discrepancies between laboratory and field studies, and enhances our ability to decipher the transport history of a river rock.

  10. How river rocks round: resolving the shape-size paradox

    CERN Document Server

    Domokos, G; Sipos, A Á; Török, Á

    2013-01-01

    River-bed sediments display two universal downstream trends: fining, in which particle size decreases; and rounding, where pebble shapes evolve toward ellipsoids. Rounding is known to result from transport-induced abrasion; however many researchers argue that the contribution of abrasion to downstream fining is negligible. This presents a paradox: downstream shape change indicates substantial abrasion, while size change apparently rules it out. Here we use laboratory experiments and numerical modeling to show quantitatively that pebble abrasion is a curvature-driven flow problem. As a consequence, abrasion occurs in two well-separated phases: first, pebble edges rapidly round without any change in axis dimensions until the shape becomes entirely convex; and second, axis dimensions are then slowly reduced while the particle remains convex. Explicit study of pebble shape evolution helps resolve the shape-size paradox by reconciling discrepancies between laboratory and field studies, and enhances our ability to ...

  11. Inductive reasoning and judgment interference: experiments on Simpson's paradox.

    Science.gov (United States)

    Fiedler, Klaus; Walther, Eva; Freytag, Peter; Nickel, Stefanie

    2003-01-01

    In a series of experiments on inductive reasoning, participants assessed the relationship between gender, success, and a covariate in a situation akin to Simpson's paradox: Although women were less successful then men according to overall statistics, they actually fared better then men at either of two universities. Understanding trivariate relationships of this kind requires cognitive routines similar to analysis of covariance. Across the first five experiments, however, participants generalized the disadvantage of women at the aggregate level to judgments referring to the different levels of the covariate, even when motivation was high and appropriate mental models were activated. The remaining three experiments demonstrated that Simpson's paradox could be mastered when the salience of the covariate was increased and when the salience of gender was decreased by the inclusion of temporal cues that disambiguate the causal status of the covariate.

  12. Paradoxes of Personal Responsibility in Mental Health Care.

    Science.gov (United States)

    Lakeman, Richard

    2016-12-01

    Personal responsibility is widely considered important in mental health recovery as well as in popular models of alcohol and drug treatment. Neo-liberal socio-political rhetoric around consumerism in health care often assumes that people are informed and responsible for their own choices and behaviour. In the mental health care context and especially in emergency or crisis settings, personal responsibility often raises particular paradoxes. People often present whose behaviour does not conform to the ideals of the responsible consumer; they may seek and/or be granted absolution from irresponsible behaviour. This paradox is explored and clinicians are urged to consider the context-bound nature of personal responsibility and how attributions of personal responsibility may conflict with policy and their own professional responsibilities to intervene to protect others.

  13. Time, Topology and the Twin Paradox

    CERN Document Server

    Luminet, J -P

    2009-01-01

    The twin paradox is the best known thought experiment associated with Einstein's theory of relativity. An astronaut who makes a journey into space in a high-speed rocket will return home to find he has aged less than a twin who stayed on Earth. This result appears puzzling, since the situation seems symmetrical, as the homebody twin can be considered to have done the travelling with respect to the traveller. Hence it is called a "paradox". In fact, there is no contradiction and the apparent paradox has a simple resolution in Special Relativity with infinite flat space. In General Relativity (dealing with gravitational fields and curved space-time), or in a compact space such as the hypersphere or a multiply connected finite space, the paradox is more complicated, but its resolution provides new insights about the structure of spacetime and the limitations of the equivalence between inertial reference frames.

  14. Collaboration and competition: the paradox of knowledge ...

    African Journals Online (AJOL)

    Collaboration and competition: the paradox of knowledge management. ... as it is understood in a late or post-capitalist organisation which is typically virtual, ... to an environment in which there is much change happening on a constant and ...

  15. six six six paradox : [luuletused] / Triin Tasuja

    Index Scriptorium Estoniae

    Tasuja, Triin

    2008-01-01

    Sisu: six six six paradox ; cat stevens ; "vahel tundub, et mu ümber..." ; sääse ; Salaalaealised ; kolkalapsed ; longin mööda lumiseid tänavaid ; punkrock dekadents ; "Igast kirjaneitsist..." ; "mina olengi see saikochick..."

  16. The Obesity Paradox in Cancer: a Review.

    Science.gov (United States)

    Lennon, Hannah; Sperrin, Matthew; Badrick, Ellena; Renehan, Andrew G

    2016-09-01

    There is a common perception that excess adiposity, commonly approximated by body mass index (BMI), is associated with reduced cancer survival. A number of studies have emerged challenging this by demonstrating that overweight and early obese states are associated with improved survival. This finding is termed the "obesity paradox" and is well recognized in the cardio-metabolic literature but less so in oncology. Here, we summarize the epidemiological findings related to the obesity paradox in cancer. Our review highlights that many observations of the obesity paradox in cancer reflect methodological mechanisms including the crudeness of BMI as an obesity measure, confounding, detection bias, reverse causality, and a specific form of the selection bias, known as collider bias. It is imperative for the oncologist to interpret the observation of the obesity paradox against the above methodological framework and avoid the misinterpretation that being obese might be "good" or "protective" for cancer patients.

  17. A Solution of the Mitra Paradox

    Directory of Open Access Journals (Sweden)

    Øyvind Grøn

    2016-11-01

    Full Text Available The “Mitra paradox” refers to the fact that while the de Sitter spacetime appears non-static in a freely falling reference frame, it looks static with reference to a fixed reference frame. The coordinate-independent nature of the paradox may be gauged from the fact that the relevant expansion scalar, θ = 3 Λ , is finite if Λ > 0 . The trivial resolution of the paradox would obviously be to set Λ = 0 . However, here it is assumed that Λ > 0 , and the paradox is resolved by invoking the concept of “expansion of space”. This is a reference-dependent concept, and it is pointed out that the solution of the Mitra paradox is obtained by taking into account the properties of the reference frame in which the coordinates are co-moving.

  18. Individualisation of care and the obesity paradox.

    Science.gov (United States)

    Haslam, David

    2014-03-01

    The obesity 'paradox' has recently been discussed based upon the observation that although obesity may be a major causative factor in certain conditions, its presence appears to be protective once that condition occurs. There is a growing body of persuasive evidence to support the obesity paradox in diseases including renal failure and heart failure. Recent evidence is reliable, adjusting more effectively for confounders such as smoking and intercurrent illness, which make lower weight an unhealthy state. The existence of the paradox highlights the fact that approaches to weight management are not as simple as inducing the loss of a few kilograms in overweight and obese individuals, and emphasises the importance of individualisation of care in obesity management taking into account age, ethnicity and comorbid illness. This article explores the individualisation of care in obesity, drawing attention to the obesity paradox in particular.

  19. Fermi's Paradox - The Last Challenge for Copernicanism?

    CERN Document Server

    Cirkovic, Milan M

    2009-01-01

    We review Fermi's paradox (or the "Great Silence" problem), not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI), but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already a more than three quarters of a century old puzzle - and a quarter of century since the last major review paper in the field by G. David Brin - Fermi's paradox has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built into various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literature on the subject. Finally, we consider the ramifications of various classes of hypotheses for the practical SETI projects. Somewhat paradoxically, it seems that the class of (neo)catastrophic hypoth...

  20. six six six paradox : [luuletused] / Triin Tasuja

    Index Scriptorium Estoniae

    Tasuja, Triin

    2008-01-01

    Sisu: six six six paradox ; cat stevens ; "vahel tundub, et mu ümber..." ; sääse ; Salaalaealised ; kolkalapsed ; longin mööda lumiseid tänavaid ; punkrock dekadents ; "Igast kirjaneitsist..." ; "mina olengi see saikochick..."

  1. Johann Madler's Resolution of Olber's Paradox

    Science.gov (United States)

    Tipler, F. J.

    1988-09-01

    In 1861, some 40 years after Olbers' discussion of the paradox which bears his name, the German astronomer Johann Heinrich Mädler argued that a dark sky would be consistent with an infinite universe if the universe began a finite time in the past. The author shows that Mädler's resolution of Olbers' paradox is essentially the same as the resolution offered by modern cosmologists.

  2. Solving the paradox of monetary profits

    OpenAIRE

    2010-01-01

    Bruun and Heyn-Johnsen (2009) state the paradox that economics has failed to provide a satisfactory explanation of how monetary profits are generated, even though the generation of a physical surplus is an established aspect of non-neoclassical economics. They emphasise that our ability to explain phenomena like the Global Financial Crisis (GFC) will be limited while ever we are still unable to explain this fundamental aspect of capitalism. In fact this paradox can be solved very simply, usin...

  3. The obesity paradox in cardiac arrest patients.

    Science.gov (United States)

    Chalkias, Athanasios; Xanthos, Theodoros

    2014-02-01

    Evidence from clinical cohorts indicates an obesity paradox in overweight and obese patients who seem to have a more favorable short-term and long-term prognosis than leaner patients. Although obese cardiac arrest victims are theoretically more difficult to be resuscitated due to difficulties in providing adequate chest compressions, ventilation, and oxygenation, research so far has shown that there is an obesity paradox in cardiac arrest.

  4. Solution to causality paradox upon total reflection

    Institute of Scientific and Technical Information of China (English)

    LIU Xiang-min; CAO Zhuang-qi; ZHU Peng-fei; SHEN Qi-shun

    2006-01-01

    A dispute about the existence of an additional time (named as the Goos-H(a)nchen time) associated with the Goos-H(a)nchen shift in total reflection has recently arisen.At the same time,an inconsistency between the optical ray model and the electromagnetic theory also appears in the optical planar waveguide.By analyzing light propagation in an optical planar waveguide with both the zigzag-ray model and the electromagnetic theory,this paper shows that the Goos-H(a)nchen time really exists,and the total time delay upon total reflection upon an ideal nonabsorbing plasma mirror is the sum of the group-delay time and the Goos-H(a)nchen time.The causality paradox of total reflection of a TM wave upon an ideal nonabsorbing plasma mirror is also solved taking into consideration the negative Goos-H(a)nchen shift.Finally,the expression of the group velocity of the guided mode in optical planar waveguide was obtained,which clearly shows that the time delay upon total reflection is the sum of the group-delay time and the Goos-H(a)nchen time at given any time.

  5. Paradoxes of cosmological physics in the beginning of the 21-st century

    CERN Document Server

    Baryshev, Yurij

    2015-01-01

    In the history of cosmology physical paradoxes played important role for development of contemporary world models. Within the modern standard cosmological model there are both observational and conceptual cosmological paradoxes which stimulate to search their solution. Confrontation of theoretical predictions of the standard cosmological model with the latest astrophysical observational data is considered. A review of conceptual problems of the Friedmann space expending models, which are in the bases of modern cosmological model, is discussed. The main paradoxes, which are discussed in modern literature, are the Newtonian character of the exact Friedmann equation, the violation of the energy conservation within any comoving local volume, violation of the limiting recession velocity of galaxies for the observed high redshift objects. Possible observational tests of the nature of the cosmological redshift are discussed

  6. Unveiling the Mobile Learning Paradox.

    Science.gov (United States)

    Mather, Carey; Cummings, Elizabeth

    2015-01-01

    A mobile learning paradox exists in Australian healthcare settings. Although it is increasingly acknowledged that timely, easy, and convenient access to health information using mobile learning technologies can enhance care and improve patient outcomes, currently there is an inability for nurses to access information at the point of care. Rapid growth in the use of mobile technology has created challenges for learning and teaching in the workplace. Easy access to educational resources via mobile devices challenges traditional strategies of knowledge and skill acquisition. Redesign of learning and teaching in the undergraduate curriculum and the development of policies to support the use of mobile learning at point of care is overdue. This study explored mobile learning opportunities used by clinical supervisors in tertiary and community-based facilities in two Australian States. Individual, organisation and systems level governance were sub-themes of professionalism that emerged as the main theme and impacts on learning and teaching in situ in healthcare environments. It is imperative healthcare work redesign includes learning and teaching that supports professional identity formation of students during work integrated learning.

  7. Braess paradox in a network of totally asymmetric exclusion processes

    Science.gov (United States)

    Bittihn, Stefan; Schadschneider, Andreas

    2016-12-01

    We study the Braess paradox in the transport network as originally proposed by Braess with totally asymmetric exclusion processes (TASEPs) on the edges. The Braess paradox describes the counterintuitive situation in which adding an edge to a road network leads to a user optimum with higher travel times for all network users. Travel times on the TASEPs are nonlinear in the density, and jammed states can occur due to the microscopic exclusion principle, leading to a more realistic description of trafficlike transport on the network than in previously studied linear macroscopic mathematical models. Furthermore, the stochastic dynamics allows us to explore the effects of fluctuations on network performance. We observe that for low densities, the added edge leads to lower travel times. For slightly higher densities, the Braess paradox occurs in its classical sense. At intermediate densities, strong fluctuations in the travel times dominate the system's behavior due to links that are in a domain-wall state. At high densities, the added link leads to lower travel times. We present a phase diagram that predicts the system's state depending on the global density and crucial path-length ratios.

  8. Cutaneous wound healing through paradoxical MAPK activation by BRAF inhibitors

    Science.gov (United States)

    Escuin-Ordinas, Helena; Li, Shuoran; Xie, Michael W.; Sun, Lu; Hugo, Willy; Huang, Rong Rong; Jiao, Jing; de-Faria, Felipe Meira; Realegeno, Susan; Krystofinski, Paige; Azhdam, Ariel; Komenan, Sara Marie D.; Atefi, Mohammad; Comin-Anduix, Begoña; Pellegrini, Matteo; Cochran, Alistair J.; Modlin, Robert L.; Herschman, Harvey R.; Lo, Roger S.; McBride, William H.; Segura, Tatiana; Ribas, Antoni

    2016-01-01

    BRAF inhibitors are highly effective therapies for the treatment of BRAFV600-mutated melanoma, with the main toxicity being a variety of hyperproliferative skin conditions due to paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway in BRAF wild-type cells. Most of these hyperproliferative skin changes improve when a MEK inhibitor is co-administered, as it blocks paradoxical MAPK activation. Here we show how the BRAF inhibitor vemurafenib accelerates skin wound healing by inducing the proliferation and migration of human keratinocytes through extracellular signal-regulated kinase (ERK) phosphorylation and cell cycle progression. Topical treatment with vemurafenib in two wound-healing mice models accelerates cutaneous wound healing through paradoxical MAPK activation; addition of a mitogen-activated protein kinase kinase (MEK) inhibitor reverses the benefit of vemurafenib-accelerated wound healing. The same dosing regimen of topical BRAF inhibitor does not increase the incidence of cutaneous squamous cell carcinomas in mice. Therefore, topical BRAF inhibitors may have clinical applications in accelerating the healing of skin wounds. PMID:27476449

  9. Solving the hard problem of Bertrand's paradox

    Energy Technology Data Exchange (ETDEWEB)

    Aerts, Diederik, E-mail: diraerts@vub.ac.be [Center Leo Apostel for Interdisciplinary Studies and Department of Mathematics, Brussels Free University, Brussels (Belgium); Sassoli de Bianchi, Massimiliano, E-mail: autoricerca@gmail.com [Laboratorio di Autoricerca di Base, Lugano (Switzerland)

    2014-08-15

    Bertrand's paradox is a famous problem of probability theory, pointing to a possible inconsistency in Laplace's principle of insufficient reason. In this article, we show that Bertrand's paradox contains two different problems: an “easy” problem and a “hard” problem. The easy problem can be solved by formulating Bertrand's question in sufficiently precise terms, so allowing for a non-ambiguous modelization of the entity subjected to the randomization. We then show that once the easy problem is settled, also the hard problem becomes solvable, provided Laplace's principle of insufficient reason is applied not to the outcomes of the experiment, but to the different possible “ways of selecting” an interaction between the entity under investigation and that producing the randomization. This consists in evaluating a huge average over all possible “ways of selecting” an interaction, which we call a universal average. Following a strategy similar to that used in the definition of the Wiener measure, we calculate such universal average and therefore solve the hard problem of Bertrand's paradox. The link between Bertrand's problem of probability theory and the measurement problem of quantum mechanics is also briefly discussed.

  10. A Quantum Cognition Analysis of the Ellsberg Paradox

    CERN Document Server

    Aerts, Diederik; Sozzo, Sandro

    2011-01-01

    The 'expected utility hypothesis' is one of the foundations of classical approaches to economics and decision theory and Savage's 'Sure-Thing Principle' is a fundamental element of it. It has been put forward that real-life situations exist, illustrated by the 'Allais' and 'Ellsberg paradoxes', in which the Sure-Thing Principle is violated, and where also the expected utility hypothesis does not hold. We have recently presented strong arguments for the presence of a double layer structure, a 'classical logical' and a 'quantum conceptual', in human thought and that the quantum conceptual mode is responsible of the above violation. We consider in this paper the Ellsberg paradox, perform an experiment with real test subjects on the situation considered by Ellsberg, and use the collected data to elaborate a model for the conceptual landscape surrounding the decision situation of the paradox. We show that it is the conceptual landscape which gives rise to a violation of the Sure-Thing Principle and leads to the pa...

  11. Antiparticle in the Light of Einstein-Podolsky-Rosen Paradox and Klein Paradox

    Institute of Scientific and Technical Information of China (English)

    NI Guang-Jiong; GUAN Hong; ZHOU Wei-Min; YAN Jun

    2000-01-01

    The original version of Einstein-Podolsky-Rosen paradox and the Klein paradox of Klein-Gordon equation are discussed to show the necessity of existence of antiparticle with its wave function being fixed unambiguously. No concept of "hole" is needed.

  12. The obesity paradox in the surgical population.

    Science.gov (United States)

    Valentijn, Tabita M; Galal, Wael; Tjeertes, Elke K M; Hoeks, Sanne E; Verhagen, Hence J; Stolker, Robert Jan

    2013-06-01

    Despite the medical hazards of obesity, recent reports examining body mass index (BMI) show an inverse relationship with morbidity and mortality in the surgical patient. This phenomenon is known as the 'obesity paradox'. The aim of this review is to summarize both the literature concerned with the obesity paradox in the surgical setting, as well as the theories explaining its causation. PubMed was searched to identify available literature. Search criteria included obesity paradox and BMI paradox, and studies in which BMI was used as a measure of body fat were potentially eligible for inclusion in this review. The obesity paradox has been demonstrated in cardiac and in non-cardiac surgery patients. Underweight and morbidly obese patients displayed the worse outcomes, both postoperatively as well as at long-term follow-up. Hypotheses to explain the obesity paradox include increased lean body mass, (protective) peripheral body fat, reduced inflammatory response, genetics and a decline in cardiovascular disease risk factors, but probably unknown factors contribute too. Patients at the extremes of BMI, both the underweight and the morbid obese, seem to have the highest postoperative morbidity and mortality hazard, which even persists at long-term. The cause of the obesity paradox is probably multi-factorial. This offers potential for future research in order to improve outcomes for persons on both sides of the 'optimum BMI'. Copyright © 2013 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  13. Quantum Phase from the Twin Paradox

    Science.gov (United States)

    Ord, G. N.

    2012-05-01

    The modern concept of spacetime usually emerges from the consideration of moving clocks on the assumption that world-lines are continuous. In this paper we start with the assumption that natural clocks are digital and that events are discrete. By taking different continuum limits we show that the phase of non-relativistic quantum mechanics and the odd metric of spacetime both emerge from the consideration of discrete clocks in relative motion. From this perspective, the continuum limit that manifests itself in 'spacetime' is an infinite mass limit. The continuum limit that gives rise to the Schrödinger equation retains a finite mass as a beat frequency superimposed on the 'Zitterbewegung' at the Compton frequency. We illustrate this in a simple model in which a Poisson process drives a relativistic clock that gives rise to a Feynman path integral, where the phase is a manifestation of the twin paradox. The example shows that the non-Euclidean character of spacetime and the wave-particle duality of quantum mechanics share a common origin. They both emerge from the necessity that clocks age at rates that are path dependent.

  14. GLP-2 administration results in increased proliferation but paradoxically an adverse outcome in a juvenile piglet model of short bowel syndrome

    DEFF Research Database (Denmark)

    Pereira-Fantini, Prue M; Nagy, Eva S; Thomas, Sarah L;

    2008-01-01

    OBJECTIVE: The objective of the present study was to examine the effect of glucagon-like peptide-2 (GLP-2) administration in a piglet, juvenile model of short bowel syndrome. MATERIALS AND METHODS: Four-week-old piglets underwent either a sham operation or 75% small bowel resection. Postoperative...

  15. The obesity paradox: an endocrine perspective.

    Science.gov (United States)

    Cheung, Yee-Ming; Joham, Anju; Marks, Sharon; Teede, Helena

    2017-07-01

    Obesity is a growing epidemic both in Australia and worldwide. Being overweight or obese is known to be adversely associated with multiple cardiovascular risk factors, such as type 2 diabetes mellitus, lipid disorders and hypertension. Despite the adverse impact of overweight and obesity, recent observational studies have suggested that in some overweight and obese individuals with established chronic disease, there is a survival advantage that is paradoxically better than individuals of normal weight. A burgeoning area of interest is the existence of this paradox in chronic endocrine disorders, especially with respect to osteoporosis and type 2 diabetes mellitus, as well as the latter's chronic complications, chronic kidney disease and coronary artery disease. In this article, we review the postulated mechanisms and latest evidence concerning the obesity paradox, with a focus on endocrine-related diseases. We discuss confounders and biases that exist in observational studies from which the paradox has been described and highlight that, despite the observed paradox, substantial literature exists supporting the benefits of weight reduction in obesity. © 2017 Royal Australasian College of Physicians.

  16. Three Paradoxes of the Future Prediction

    Directory of Open Access Journals (Sweden)

    D. V. Pivovarov

    2015-02-01

    Full Text Available The paper is devoted to the issue of predicting the future. While creating the future image of the mankind as a whole, and Russia in particular, extrapolated some 50 or 100 years ahead, such cultural forms as religion, philosophy, education and art make their significant impact. However, philosophy plays a special role of critical methodology in coordinating the futurological efforts. It works as a tuning fork that tunes up the orchestra of various sciences and other forms of social consciousness. Being dialectical, philosophers find out and analyze the contradictions – paradoxes, antinomies, and aporias - involved in such activities as prophesizing, prognosticating, predicting and foreseeing. On the basis of the retrospective analysis, the author considers the most significant paradoxes facing the futurologists engaged in predicting the general course of historic events; the paradoxes being denoted as follows: the antinomy of academic ignorance, paradox of newness and paradox of an emergent effect. The analysis results in conclusion that the large-scale, long-term «scientific predictions of the future», claiming to be the truth and pretending for historical value and accuracy, are impossible or at least doubtful. Nevertheless, global prognoses are highly valued, widely discussed and always in demand in society due to the purposeful human intellect. 

  17. Three Paradoxes of the Future Prediction

    Directory of Open Access Journals (Sweden)

    D. V. Pivovarov

    2012-01-01

    Full Text Available The paper is devoted to the issue of predicting the future. While creating the future image of the mankind as a whole, and Russia in particular, extrapolated some 50 or 100 years ahead, such cultural forms as religion, philosophy, education and art make their significant impact. However, philosophy plays a special role of critical methodology in coordinating the futurological efforts. It works as a tuning fork that tunes up the orchestra of various sciences and other forms of social consciousness. Being dialectical, philosophers find out and analyze the contradictions – paradoxes, antinomies, and aporias - involved in such activities as prophesizing, prognosticating, predicting and foreseeing. On the basis of the retrospective analysis, the author considers the most significant paradoxes facing the futurologists engaged in predicting the general course of historic events; the paradoxes being denoted as follows: the antinomy of academic ignorance, paradox of newness and paradox of an emergent effect. The analysis results in conclusion that the large-scale, long-term «scientific predictions of the future», claiming to be the truth and pretending for historical value and accuracy, are impossible or at least doubtful. Nevertheless, global prognoses are highly valued, widely discussed and always in demand in society due to the purposeful human intellect. 

  18. The Lindley paradox in optical interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Mauri, Camillo [Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, I-20133 Milano (Italy); Paris, Matteo G.A., E-mail: matteo.paris@fisica.unimi.it [Quantum Technology Lab, Dipartimento di Fisica, Università degli Studi di Milano, I-20133 Milano (Italy); CNISM, Unità Milano Statale, I-20133 Milano (Italy); INFN, Sezione di Milano, I-20133 Milano (Italy)

    2016-02-05

    The so-called Lindley paradox is a counterintuitive statistical effect where the Bayesian and frequentist approaches to hypothesis testing give radically different answers, depending on the choice of the prior distribution. In this paper we address the occurrence of the Lindley paradox in optical interferometry and discuss its implications for high-precision measurements. In particular, we focus on phase estimation by Mach–Zehnder interferometers and show how to mitigate the conflict between the two approaches by using suitable priors. - Highlights: • We address the occurence of Lindley paradox in interferometry and discuss its implications for high-precision measurements. • We show how to mitigate the conflict between Bayesian and frequentist approach to interferometry using suitable priors. • Our results apply to calibration of homodyne detectors for quantum tomography.

  19. Efficacy paradox and proportional contextual effect (PCE).

    Science.gov (United States)

    Zhang, Weiya; Doherty, Michael

    2017-07-20

    The "efficacy paradox" is when the effect of a treatment tested in an RCT, or evidence-based guideline advice, differs markedly from treatment benefits observed in clinical practice. This arises because in RCT reporting and guideline development treatment efficacy is judged by the separation of the treatment group from the placebo group (the specific treatment effect) whereas in clinical practice it is the overall treatment effect, which includes both specific and contextual responses, that patients experience. This paradox causes a disconnect between guidelines and clinical practice and ignores the importance of contextual response in clinical care. This article fully explains and discusses these issues and presents a possible way to reduce the paradox through an alteration in RCT reporting that shifts the focus to overall treatment benefit and the proportion ("proportional contextual effect") that is explained by placebo and contextual effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Nietzsche et les paradoxes de la force

    Directory of Open Access Journals (Sweden)

    Arnaud François

    2011-06-01

    Full Text Available According to this paper, the Nietzschean notion of force actually consists of a number of paradoxes, which I seek to formulate through the philosophical problems they pose. These paradoxes revolve around this fundamental paradox: on the one hand, force is able to rise and fall, but precisely how could such an increase and such a decrease be designed, as far as only what is given once for all can accept quantitative determinations? I come to draw two methods to answer this question (contrariety between two positive forces, reactivity of one force against the other, which suggest two ways of posing the biological and medical problems today, related to the notions of health and disease, in the scope of which Nietzsche has encountered it.

  1. Quantum, Photo-Electric Single Capacitor Paradox

    CERN Document Server

    Kapor, Darko

    2009-01-01

    In this work single capacitor paradox (a variation of the remarkable two capacitor paradox) is considered in a new, quantum discrete form. Simply speaking we consider well-known usual, photoelectric effect experimental device, i.e. photo electric cell, where cathode and anode are equivalently charged but non-connected. It, obviously, represents a capacitor that initially, i.e. before action of the photons with individual energy equivalent to work function, holds corresponding energy of the electrical fields between cathode and anode. Further, we direct quantum discretely photons, one by one, toward cathode where according to photo-electrical effect electrons discretely, one by one, will be emitted and directed toward anode. It causes discrete discharge of the cell, i.e. capacitor and discrete decrease of the electrical field. Finally, total discharge of the cell, i.e. capacitor, and total disappearance of the electrical field and its energy will occur. Given, seemingly paradoxical, capacitor total energy loss...

  2. Origin of the blackhole information paradox

    CERN Document Server

    Brustein, Ram

    2012-01-01

    It is argued that the blackhole information paradox originates from treating the blackhole geometry as strictly classical. It is further argued that the theory of quantum fields in a classical curved space with a horizon is an ill posed problem. If the geometry is allowed to fluctuate quantum mechanically, then the horizon effectively disappears. The sharp horizon emerges only in the classical limit when the ratio of the Compton wavelength of the black hole to its Schwarzschild radius vanishes. The region of strong gravity that develops when matter collapses to form the blackhole remains visible to the whole of spacetime and has to be described by a microscopic theory of strong gravity. The arguments imply that the information paradox is demoted from a paradox involving fundamental principles of physics to the problem of describing how matter at the highest densities gravitates.

  3. Generalized friendship paradox in networks with tunable degree-attribute correlation.

    Science.gov (United States)

    Jo, Hang-Hyun; Eom, Young-Ho

    2014-08-01

    One of the interesting phenomena due to topological heterogeneities in complex networks is the friendship paradox: Your friends have on average more friends than you do. Recently, this paradox has been generalized for arbitrary node attributes, called the generalized friendship paradox (GFP). The origin of GFP at the network level has been shown to be rooted in positive correlations between degrees and attributes. However, how the GFP holds for individual nodes needs to be understood in more detail. For this, we first analyze a solvable model to characterize the paradox holding probability of nodes for the uncorrelated case. Then we numerically study the correlated model of networks with tunable degree-degree and degree-attribute correlations. In contrast to the network level, we find at the individual level that the relevance of degree-attribute correlation to the paradox holding probability may depend on whether the network is assortative or dissortative. These findings help us to understand the interplay between topological structure and node attributes in complex networks.

  4. Experimental investigation of quantum Simpson's paradox

    Science.gov (United States)

    Li, Yu-Long; Tang, Jian-Shun; Wang, Yi-Tao; Wu, Yu-Chun; Han, Yong-Jian; Li, Chuan-Feng; Guo, Guang-Can; Yu, Ying; Li, Mi-Feng; Zha, Guo-Wei; Ni, Hai-Qiao; Niu, Zhi-Chuan

    2013-07-01

    The well-known Simpson's paradox, or Yule-Simpson (YS) effect, is often encountered in social-science and medical-science statistics. It occurs when the correlations present in different groups are reversed if the groups are combined. Simpson's paradox also exists in quantum measurements. In this Brief Report, we experimentally realized two analogous effects: the quantum-classical YS effect and the quantum-quantum YS effect in the quantum-dot system. We also compared the probability of obtaining those two effects under identical quantum measurements and found that the quantum-quantum YS effect is more likely to occur than the quantum-classical YS effect.

  5. The Paradox of Two Charged Capacitors

    CERN Document Server

    Singal, Ashok K

    2013-01-01

    It is shown that the famous paradox of two charged capacitors is successfully resolved if one properly considers all the energy changes in the system when some of the charges are transferred from one capacitor to the other. It happens so even when the connecting wire has an identically zero resistance, giving rise to no Ohmic losses in the wire. It is shown that in such a case the "missing energy" goes into the kinetic energy of conducting charges. It is shown that radiation plays no significant role in resolving the paradox. The problem can also be formulated and successfully resolved in an alternate form, without involving connecting wires in a circuit.

  6. The Myth of the Twin Paradox

    CERN Document Server

    Fischer, E

    2010-01-01

    One of the most discussed peculiarities of Einstein's theory of relativity is the twin paradox, the fact that the time between two events in space-time appears to depend on the path between these events. We show that this time discrepancy results only from faulty assumptions in the transition from one reference system to another. The twin paradox does not exist. But the Lorentz invariance of the theory has strong consequences, if we assume that it is valid not only locally, but also on cosmic scale.

  7. Some reflections on the Renewal-theory paradox in queueing theory

    Directory of Open Access Journals (Sweden)

    Robert B. Cooper

    1998-01-01

    Full Text Available The classical renewal-theory (waiting time, or inspection paradox states that the length of the renewal interval that covers a randomly-selected time epoch tends to be longer than an ordinary renewal interval. This paradox manifests itself in numerous interesting ways in queueing theory, a prime example being the celebrated Pollaczek-Khintchine formula for the mean waiting time in the M/G/1 queue. In this expository paper, we give intuitive arguments that “explain” why the renewal-theory paradox is ubiquitous in queueing theory, and why it sometimes produces anomalous results. In particular, we use these intuitive arguments to explain decomposition in vacation models, and to derive formulas that describe some recently-discovered counterintuitive results for polling models, such as the reduction of waiting times as a consequence of forcing the server to set up even when no work is waiting.

  8. Evaluating paradox walnut rootstocks for resistance to Armillaria root disease

    Science.gov (United States)

    The most common Juglans regia (English walnut) rootstock in California is Paradox, a hybrid between J. hindsii (Northern California black walnut) and J. regia. Unfortuntely, Paradox rootstock is highly susceptible to Armillaria root disease. The relative resistance of new clonal, Paradox rootstock...

  9. Reversal of a Suspected Paradoxical Reaction to Zopiclone with Flumazenil

    DEFF Research Database (Denmark)

    Jordahn, Zarah; Andersen, Cheme; Roust Aaberg, Anne Marie

    2016-01-01

    ), the patient became agitated and was confused, a possible paradoxical reaction to benzodiazepines. These symptoms were immediately resolved after treatment with flumazenil, usually used to reverse the adverse effects of benzodiazepines or NBRAs and to reverse paradoxical reactions to benzodiazepines. This case...... indicates that zopiclone induced behavioral changes resembling a paradoxical reaction to benzodiazepines and these symptoms may be treated with flumazenil....

  10. HOW STRONG IS POLISH FOOTBALL? "HOST PARADOX" IN FIFA'S RANKING

    Directory of Open Access Journals (Sweden)

    Marek M. Kamiński

    2012-06-01

    Full Text Available The paper analyzes unintiutive properties (paradoxes of the FIFA's ranking of national football teams. The most surprising phenomenon is underrating the teams of the main championship tournament hosts. This "host effect" follows the absence of hosts in preliminaries and the resulting restriction of hosts' pre-tournament matches to friendlies that enter the FIFA system with low weights. Various models built with the FIFA data allow to estimate that the place of the Polish team as a host of Euro 2012 was lowered from 16 to 35 positions.

  11. A Solution to Two Paradoxes of International Capital Flows

    Institute of Scientific and Technical Information of China (English)

    JIANDONG; JU; SHANG-JIN; WEI

    2014-01-01

    International capital flows from rich to poor countries can be regarded as either too small(the Lucas paradox in a one-sector model)or too large(when compared with the logic of factor price equalization in a two-sector model).To resolve the paradoxes,we introduce a non-neoclassical model which features financial contracts and firm heterogeneity.In our model,free trade in goods does not imply equal returns to capital across countries.In addition,rich patterns of gross capital flows emerge as a function of financial and property rights institutions.A poor country with an inefficient financial system may simultaneously experience an outflow of financial capital but an inflow of FDI,resulting in a small net flow.In comparison,a country with a low capital-to-labor ratio but a high risk of expropriation may experience an outflow of financial capital without a compensating inflow of FDI.

  12. The obesity paradox: understanding the effect of obesity on mortality among individuals with cardiovascular disease.

    Science.gov (United States)

    Banack, Hailey R; Kaufman, Jay S

    2014-05-01

    To discuss possible explanations for the obesity paradox and explore whether the paradox can be attributed to a form of selection bias known as collider stratification bias. The paper is divided into three parts. First, possible explanations for the obesity paradox are reviewed. Second, a simulated example is provided to describe collider stratification bias and how it could generate the obesity paradox. Finally, an example is provided using data from 17,636 participants in the US National and Nutrition Examination Survey (NHANES III). Generalized linear models were fit to assess the effect of obesity on mortality both in the general population and among individuals with diagnosed cardiovascular disease (CVD). Additionally, results from a bias analysis are presented. In the general population, the adjusted risk ratio relating obesity and all-cause mortality was 1.24 (95% CI 1.11, 1.39). Adjusted risk ratios comparing obese and non-obese among individuals with and without CVD were 0.79 (95% CI 0.68, 0.91) and 1.30 (95% CI=1.12, 1.50), indicating that obesity has a protective association among individuals with CVD. Results demonstrate that collider stratification bias is one plausible explanation for the obesity paradox. After conditioning on CVD status in the design or analysis, obesity can appear protective among individuals with CVD. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Does the Vulnerability Paradox in PTSD Apply to Women and Men? An Exploratory Study.

    Science.gov (United States)

    Dückers, Michel L A; Olff, Miranda

    2017-04-01

    Recent research suggests that greater country vulnerability is associated with a decreased, rather than increased, risk of mental health problems. Because societal parameters may have gender-specific implications, our objective was to explore whether the "vulnerability paradox" equally applies to women and men. Lifetime posttraumatic stress disorder (PTSD) prevalence data for women and men were retrieved from 11 population studies (N = 57,031): conducted in Australia, Brazil, Canada, France, Lebanon, Mexico, Netherlands, Portugal, Sweden, Switzerland, and the United States. We tested statistical models with vulnerability, gender, and their interaction as predictors. The average lifetime PTSD prevalence in women was at least twice as high as it was in men and the vulnerability paradox existed in the prevalence data for women and men (R(2) = .70). We could not confirm the possibility that gender effects are modified by socioeconomic and cultural country characteristics. Issues of methodology, language, and cultural validity complicate international comparisons. Nevertheless, this international sample points at a parallel paradox: The vulnerability paradox was confirmed for both women and men. The absence of a significant interaction between gender and country vulnerability implies that possible explanations for the paradox at the country-level do not necessarily require gender-driven distinction. Copyright © 2017 International Society for Traumatic Stress Studies.

  14. Art's Pedagogical Paradox

    Science.gov (United States)

    Kalin, Nadine M.

    2014-01-01

    This article contributes to conversations concerning art education futures through engaging alternative relations between art, education, and democracy that mobilize education as art projects associated with the "pedagogical turn" as sites of liminality and paradox. An analysis of the art project, Pedagogical Factory, is used to outline…

  15. Body composition phenotypes and obesity paradox.

    Science.gov (United States)

    Prado, Carla M; Gonzalez, M Cristina; Heymsfield, Steven B

    2015-11-01

    The obesity paradox is a highly controversial concept that may be attributed to methodological limitations related to its identification. One of the primary concerns is the use of BMI to define obesity. This index does not differentiate lean versus adipose tissue compartments (i.e. body composition) confounding health consequences for morbidity and mortality, especially in clinical populations. This review will describe the past year's evidence on the obesity paradox phenomenon, primarily focusing on the role of abnormal body composition phenotypes in explaining the controversies observed in the literature. In spite of the substantial number of articles investigating the obesity paradox phenomenon, less than 10% used a direct measure of body composition and when included, it was not fully explored (only adipose tissue compartment evaluated). When lean tissue or muscle mass is taken into account, the general finding is that a high BMI has no protective effect in the presence of low muscle mass and that it is the latter that associates with poor prognosis. In view of the body composition variability of patients with identical BMI, it is unreasonable to rely solely on this index to identify obesity. The consequences of a potential insubstantial obesity paradox are mixed messages related to patient-related prognostication.

  16. Toward a Theory of Coaching Paradox

    Science.gov (United States)

    Barnson, Steven C.

    2014-01-01

    Multiple tensions exist as part of the coaching process. How a coach responds to these tensions is a fundamental determinant of an athlete or team's fate. In today's highly competitive, socially demanding, and ever-changing sports environment, and as the expectations on coaches become more complex, the paradox becomes a critical lens to…

  17. Paradoxical Interventions and the Counseling Process.

    Science.gov (United States)

    McMillan, Douglas N.; Johnson, Mark E.

    1995-01-01

    Used analogue format to compare relative effects of two paradoxical interventions (symptom scheduling and negative consequences of change), a relaxation directive, and a session summary condition on clients' perceptions of a mental health counselor, counseling expectations, and attributions. Results indicated differential effects on perceptions of…

  18. The Fermi paradox and coronary artery disease

    National Research Council Canada - National Science Library

    Gottlieb, Ilan; Lima, Ronaldo Souza Leão

    2014-01-01

    ..., led Fermi to ask the famous question: "Where is everybody?" Fermi was confronted with a paradox that involved probability, scale, and evidence. Coronary artery disease (CAD) presents a similar challenge. The pathophysiological importance of nonobstructive CAD is well known, as two-thirds of acute coronary syndromes (ACS) originate...

  19. An alternative resolution to the Mansuripur paradox

    Science.gov (United States)

    Redfern, Francis

    2016-04-01

    In 2013 an article published online by the journal Science declared that the paradox proposed by Masud Mansuripur was resolved. This paradox concerns a point charge-Amperian magnetic dipole system as seen in a frame of reference where they are at rest and one in which they are moving. In the latter frame an electric dipole appears on the magnetic dipole. A torque is then exerted upon the electric dipole by the point charge, a torque that is not observed in the at-rest frame. Mansuripur points out this violates the relativity principle and suggests the Lorentz force responsible for the torque be replaced by the Einstein-Laub force. The resolution of the paradox reported by Science, based on numerous papers in the physics literature, preserves the Lorentz force but depends on the concept of hidden momentum. Here I propose a different resolution based on the overlooked fact that the charge-magnetic dipole system contains linear and angular electromagnetic field momentum. The time rate of change of the field angular-momentum in the frame through which the system is moving cancels that due to the charge-electric dipole interaction. From this point of view hidden momentum is not needed in the resolution of the paradox.

  20. Paradoxical Narrators in Heart of Darkness

    Institute of Scientific and Technical Information of China (English)

    刘彤

    2008-01-01

    Conrad's novel involves a great deal of different authorial and personal narrators,which are not onlyexpensive,but often surprising and paradoxical as well.Heart of Darkness is a case in point.It is a way to suggest thatthe exceptional thematic complication of Heart of Darkness is partly dependent on the different degrees of perception shownby the novella's narrators.

  1. Toward a Theory of Coaching Paradox

    Science.gov (United States)

    Barnson, Steven C.

    2014-01-01

    Multiple tensions exist as part of the coaching process. How a coach responds to these tensions is a fundamental determinant of an athlete or team's fate. In today's highly competitive, socially demanding, and ever-changing sports environment, and as the expectations on coaches become more complex, the paradox becomes a critical lens to…

  2. R&D in SMEs : A paradox?

    NARCIS (Netherlands)

    Ortega Argiles, Raquel; Vivarelli, Marco; Voigt, Peter

    2009-01-01

    This paper has three objectives: (1) to survey the relevant literature addressing the (apparent) paradox of Research & Development investments carried out within Small and Medium Enterprises; (2) to provide focused summaries of the articles in this special issue; (3) to draw some general conclusions

  3. Art's Pedagogical Paradox

    Science.gov (United States)

    Kalin, Nadine M.

    2014-01-01

    This article contributes to conversations concerning art education futures through engaging alternative relations between art, education, and democracy that mobilize education as art projects associated with the "pedagogical turn" as sites of liminality and paradox. An analysis of the art project, Pedagogical Factory, is used to outline…

  4. Calcium paradox and calcium entry blockers

    NARCIS (Netherlands)

    Ruigrok, T.J.C.; Slade, A.M.; Nayler, W.G.; Meijler, F.L.

    1984-01-01

    Reperfusion of isolated hearts with calcium-containing solution after a short period of calcium-free perfusion results in irreversible cell damage (calcium paradox). This phenomenon is characterized by an excessive influx of calcium into the cells, the rapid onset of myocardial contracture, exhausti

  5. Biofuel Mandating and the Green Paradox

    NARCIS (Netherlands)

    Okullo, Samuel; Reynes, F.; Hofkes, M.

    2016-01-01

    The theory on the green paradox has focused primarily on the consumption of a clean substitute produced using a static technology. In reality, we observe the gradual accumulation of the clean substitute’s capacity, suggesting that supply decisions for the clean substitute and finite carbon resource

  6. Micro-Macro Paradoxes of Entrepreneurship

    DEFF Research Database (Denmark)

    Søgaard, Villy

    2008-01-01

    Artiklen tager afsæt i det såkaldte micro-macro paradox fra Aids-Efficiency litteraturen og argumenterer for, at en tilsvarende problemstilling bør inddrages i vurderingen af f.eks. de beskæftigelsesmæssige konsekvenser af entrepreneuriel virksomhed. Den påviser også i en gennemgang af litteraturen...

  7. The Faint Young Sun Paradox: A Simplified Thermodynamic Approach

    Directory of Open Access Journals (Sweden)

    F. Angulo-Brown

    2012-01-01

    Full Text Available Classical models of the Sun suggest that the energy output in the early stage of its evolution was 30 percent less than today. In this context, radiative balance alone between The Sun and the Earth was not sufficient to explain the early presence of liquid water on Earth’s surface. This difficulty is called the faint young Sun paradox. Many proposals have been published to solve this paradox. In the present work, we propose an oversimplified finite-time thermodynamic approach that describes the air convective cells in the Earth atmosphere. This model introduces two atmospheric modes of thermodynamic performance: a first mode consisting in the maximization of the power output of the convective cells (maximum power regime and a second mode that consists in maximizing a functional representing a good trade-off between power output and entropy production (the ecological regime. Within the assumptions of this oversimplified model, we present different scenarios of albedo and greenhouse effects that seem realistic to preserve liquid water on the Earth in the early stage of formation.

  8. The Braess Paradox in a network of totally asymmetric exclusion processes

    CERN Document Server

    Bittihn, Stefan

    2016-01-01

    We study the Braess paradox in the transport network as originally proposed by Braess with totally asymmetric exclusion processes (TASEPs) on the edges. The Braess paradox describes the counterintuitive situation where adding an additional edge to a road network leads to a user optimum with higher traveltimes for all network users. Traveltimes on the TASEPs are nonlinear in the density and jammed states can occur due to the microscopic exclusion principle. Furthermore the individual edges influence each other. This leads to a much more realistic description of traffic-like transport on the network than in previously studied linear macroscopic mathematical models. Furthermore the stochastic dynamics allows to explore the effects of fluctuations on the network performance. We observe that for low densities the added edge leads to lower traveltimes. For slightly higher densities the Braess paradox in its classical sense occurs in a small density regime. In a large regime of intermediate densities strong fluctuat...

  9. Glycation: the angiogenic paradox in aging and age-related disorders and diseases.

    Science.gov (United States)

    Roca, F; Grossin, N; Chassagne, P; Puisieux, F; Boulanger, E

    2014-05-01

    Angiogenesis is generally a quiescent process which, however, may be modified by different physiological and pathological conditions. The "angiogenic paradox" has been described in diabetes because this disease impairs the angiogenic response in a manner that differs depending on the organs involved and disease evolution. Aging is also associated with pro- and antiangiogenic processes. Glycation, the post-translational modification of proteins, increases with aging and the progression of diabetes. The effect of glycation on angiogenesis depends on the type of glycated proteins and cells involved. This complex link could be responsible for the "angiogenic paradox" in aging and age-related disorders and diseases. Using diabetes as a model, the present work has attempted to review the age-related angiogenic paradox, in particular the effects of glycation on angiogenesis during aging. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. The Role of Secondary Calciprotein Particles in the Mineralisation Paradox of Chronic Kidney Disease.

    Science.gov (United States)

    Cai, Michael M X; Smith, Edward R; Tan, Sven-Jean; Hewitson, Timothy D; Holt, Stephen G

    2017-08-31

    Mineralisation paradox is prevalent in chronic kidney disease and ageing where increased vascular calcification is accompanied by reduced bone mineralisation and osteopenia. Secondary calciprotein particles (CPP2), colloidal nanoparticles containing hydroxyapatite crystal stabilised by a protein shell, have been implicated in vascular calcification in chronic kidney disease. Here, we describe the effect of CPP2 on osteoblasts and vascular smooth muscle cells (VSMC) mineralisation in an in vitro model system. The mineralisation paradox can be simulated in vitro by the addition of phosphate ions (Pi, 3 mM) and CPP2 (10 µg/ml of Ca equivalent). Pi alone induced osteoblast mineralisation but had no effect on VSMC mineralisation. CPP2 alone had no effect on mineralisation in either cell line, but when combined with elevated Pi, reduced osteoblast-like mineralisation (P paradox, and may provide a potential mechanistic link to explain these clinical observations.

  11. A resolution to the blue whiting (Micromesistius poutassou) population paradox?

    Science.gov (United States)

    Pointin, Fabien; Payne, Mark R

    2014-01-01

    We provide the strongest evidence to date supporting the existence of two independent blue whiting (Micromesistius poutassou (Risso, 1827)) populations in the North Atlantic. In spite of extensive data collected in conjunction with the fishery, the population structure of blue whiting is poorly understood. On one hand, genetic, morphometric, otolith and drift modelling studies point towards the existence of two populations, but, on the other hand, observations of adult distributions point towards a single population. A paradox therefore arises in attempting to reconcile these two sets of information. Here we analyse 1100 observations of blue whiting larvae from the Continuous Plankton Recorder (CPR) from 1948-2005 using modern statistical techniques. We show a clear spatial separation between a northern spawning area, in the Rockall Trough, and a southern one, off the Porcupine Seabight. We further show a difference in the timing of spawning between these sites of at least a month, and meaningful differences in interannual variability. The results therefore support the two-population hypothesis. Furthermore, we resolve the paradox by showing that the acoustic observations cited in support of the single-population model are not capable of resolving both populations, as they occur too late in the year and do not extend sufficiently far south to cover the southern population: the confusion is the result of a simple observational artefact. We conclude that blue whiting in the North Atlantic comprises two populations.

  12. A resolution to the blue whiting (Micromesistius poutassou population paradox?

    Directory of Open Access Journals (Sweden)

    Fabien Pointin

    Full Text Available We provide the strongest evidence to date supporting the existence of two independent blue whiting (Micromesistius poutassou (Risso, 1827 populations in the North Atlantic. In spite of extensive data collected in conjunction with the fishery, the population structure of blue whiting is poorly understood. On one hand, genetic, morphometric, otolith and drift modelling studies point towards the existence of two populations, but, on the other hand, observations of adult distributions point towards a single population. A paradox therefore arises in attempting to reconcile these two sets of information. Here we analyse 1100 observations of blue whiting larvae from the Continuous Plankton Recorder (CPR from 1948-2005 using modern statistical techniques. We show a clear spatial separation between a northern spawning area, in the Rockall Trough, and a southern one, off the Porcupine Seabight. We further show a difference in the timing of spawning between these sites of at least a month, and meaningful differences in interannual variability. The results therefore support the two-population hypothesis. Furthermore, we resolve the paradox by showing that the acoustic observations cited in support of the single-population model are not capable of resolving both populations, as they occur too late in the year and do not extend sufficiently far south to cover the southern population: the confusion is the result of a simple observational artefact. We conclude that blue whiting in the North Atlantic comprises two populations.

  13. Ultralarge lotteries : Analyzing the Lottery Paradox using non-standard analysis

    NARCIS (Netherlands)

    Wenmackers, Sylvia

    2013-01-01

    A popular way to relate probabilistic information to binary rational beliefs is the Lockean Thesis, which is usually formalized in terms of thresholds. This approach seems far from satisfactory: the value of the thresholds is not well-specified and the Lottery Paradox shows that the model violates

  14. Non-Thermal Corrections to Hawking Radiation Versus the Information Paradox

    CERN Document Server

    Dvali, Gia

    2015-01-01

    We provide a model-independent argument indicating that for a black hole of entropy N the non-thermal deviations from Hawking radiation, per each emission time, are of order 1/N, as opposed to exp(-N). This fact abolishes the standard a priory basis for the information paradox.

  15. Towards a Resolution of the New Core Paradox

    Science.gov (United States)

    Driscoll, P. E.; Davies, C. J.

    2015-12-01

    Paleomagnetic observations that indicate a geodynamo as old as 4.2 Gyr are at odds with the "new core paradox", which claims insufficient energy to drive the ancient geodynamo prior to inner core nucleation. Recent upward revisions to the thermal conductivity of iron in the core strain the energy budget by increasing the conductive heat flow that must be overcome in order to drive thermal convection and maintain an ancient geodynamo. We address this paradox by computing thermal-magnetic evolutions of the Earth using a 1-D model with parameterizations for heat sources and sinks in the mantle and core. This model includes a number of important new features that have not been previous coupled in a single model. New features in the mantle model include enhanced mantle heat loss to due extrusive volcanism, crust formation and insolation, and latent heating due to magma ocean solidification. New features in the core model include realistic iron conductivities, time-dependent partitioning of light elements (O, S, and Si) between solid and liquid and their effect on the liquidus depression and gravitational energy release. Core evolutions derived from an energy model are compared to an energy-entropy model, which accounts for ohmic dissipation. We identify the conditions necessary to avoid shut-down of the geodynamo prior to inner core nucleation and to maintain a strong magnetic field over the last 4.2 Gyr. Using a dipole field scaling law derived from numerical dynamo models we compare the predicted paleo-dipole intensity to the paleointensity record and speculate on possible observational evidence for the inner core nucleation event.

  16. The Policy Maker's Anguish: Regulating Personal Data Behavior Between Paradoxes and Dilemmas

    Science.gov (United States)

    Compañó, Ramón; Lusoli, Wainer

    Regulators in Europe and elsewhere are paying great attention to identity, privacy and trust in online and converging environments. Appropriate regulation of identity in a ubiquitous information environment is seen as one of the major drivers of the future Internet economy. Regulation of personal identity data has come to the fore including mapping conducted on digital personhood by the OECD; work on human rights and profiling by the Council of Europe andmajor studies by the European Commission with regard to self-regulation in the privacy market, electronic identity technical interoperability and enhanced safety for young people. These domains overlap onto an increasingly complex model of regulation of individuals' identity management, online and offline. This chapter argues that policy makers struggle to deal with issues concerning electronic identity, due to the apparently irrational and unpredictable behavior of users when engaging in online interactions involving identity management. Building on empirical survey evidence from four EU countries, we examine the first aspect in detail - citizens' management of identity in a digital environment. We build on data from a large scale (n = 5,265) online survey of attitudes to electronic identity among young Europeans (France, Germany, Spain, UK) conducted in August 2008. The survey asked questions about perceptions and acceptance of risks, general motivations, attitudes and behaviors concerning electronic identity. Four behavioral paradoxes are identified in the analysis: a privacy paradox (to date well known), but also a control paradox, a responsibility paradox and an awareness paradox. The chapter then examines the paradoxes in relation of three main policy dilemmas framing the debate on digital identity. The paper concludes by arguing for an expanded identity debate spanning policy circles and the engineering community.

  17. Paradox of Denials in All My Sons

    Institute of Scientific and Technical Information of China (English)

    雷慧慧

    2014-01-01

    Arthur Miller, who was one of the greatest American playwrights of the 20th century. In All My Sons, different sorts of denials lead to the family’s collapse and Keller’s death. Paradoxically, the very denial that is designed to protect him from prose-cution and incarceration is followed by a chain of events that lead to Keller’s own self-imprisonment and self-imposed execu-tion. Denial also exists in the history of some countries, such as Germany, Japan and America and so on. My paper aims to ex-plore the paradox of denial both in our history and in literature works. My paper will demonstrate that denial has some negative effects both on the outer-world and the inner-world through thorough analysis on the characters in All My Sons.

  18. The happiness-income paradox revisited.

    Science.gov (United States)

    Easterlin, Richard A; McVey, Laura Angelescu; Switek, Malgorzata; Sawangfa, Onnicha; Zweig, Jacqueline Smith

    2010-12-28

    The striking thing about the happiness-income paradox is that over the long-term--usually a period of 10 y or more--happiness does not increase as a country's income rises. Heretofore the evidence for this was limited to developed countries. This article presents evidence that the long term nil relationship between happiness and income holds also for a number of developing countries, the eastern European countries transitioning from socialism to capitalism, and an even wider sample of developed countries than previously studied. It also finds that in the short-term in all three groups of countries, happiness and income go together, i.e., happiness tends to fall in economic contractions and rise in expansions. Recent critiques of the paradox, claiming the time series relationship between happiness and income is positive, are the result either of a statistical artifact or a confusion of the short-term relationship with the long-term one.

  19. The happiness–income paradox revisited

    Science.gov (United States)

    Easterlin, Richard A.; McVey, Laura Angelescu; Switek, Malgorzata; Sawangfa, Onnicha; Zweig, Jacqueline Smith

    2010-01-01

    The striking thing about the happiness–income paradox is that over the long-term —usually a period of 10 y or more—happiness does not increase as a country's income rises. Heretofore the evidence for this was limited to developed countries. This article presents evidence that the long term nil relationship between happiness and income holds also for a number of developing countries, the eastern European countries transitioning from socialism to capitalism, and an even wider sample of developed countries than previously studied. It also finds that in the short-term in all three groups of countries, happiness and income go together, i.e., happiness tends to fall in economic contractions and rise in expansions. Recent critiques of the paradox, claiming the time series relationship between happiness and income is positive, are the result either of a statistical artifact or a confusion of the short-term relationship with the long-term one. PMID:21149705

  20. A history of the Allais paradox.

    Science.gov (United States)

    Heukelom, Floris

    2015-03-01

    This article documents the history of the Allais paradox, and shows that underneath the many discussions of the various protagonists lay different, irreconcilable epistemological positions. Savage, like his mentor von Neumann and similar to economist Friedman, worked from an epistemology of generalized characterizations. Allais, on the other hand, like economists Samuelson and Baumol, started from an epistemology of exact descriptions in which every axiom was an empirical claim that could be refuted directly by observations. As a result, the two sides failed to find a common ground. Only a few decades later was the now so-called Allais paradox rediscovered as an important precursor when a new behavioural economic subdiscipline started to adopt the epistemology of exact descriptions and its accompanying falsifications of rational choice theory.

  1. A Canadian paradox: Tommy Douglas and eugenics.

    Science.gov (United States)

    Shevell, Michael

    2012-01-01

    Tommy Douglas is an icon of Canadian 20th Century political history and is considered by many as the "Father" of Medicare, a key component of our national identity. Throughout his career, he was associated at both the provincial and federal levels with progressive causes concerning disadvantaged populations. In his sociology Master's thesis written in the early 1930's, Douglas endorsed eugenic oriented solutions such as segregation and sterilization to address what was perceived to be an endemic and biologically determined problem. At first glance, this endorsement of eugenics appears to be paradoxical, but careful analysis revealed that this paradox has multiple roots in religion, political belief, historical exposure and our own desire to view our collective history in a favourable light.

  2. Adaptationism fails to resolve Fermi's paradox

    Directory of Open Access Journals (Sweden)

    Ćirković Milan M.

    2005-01-01

    Full Text Available One of the most interesting problems in the nascent discipline of astrobiology is more than half-century old Fermi's paradox: why, considering extraordinary young age of Earth and the Solar System in the Galactic context, don't we perceive much older intelligent communities or signposts of their activity? In spite of a vigorous research activity in recent years, especially bolstered by successes of astrobiology in finding extrasolar planets and extremophiles, this problem (also known as the "Great Silence" or "astrosociological" paradox remains as open as ever. In a previous paper, we have discussed a particular evolutionary solution suggested by Karl Schroeder based on the currently dominant evolutionary doctrine of adaptationism. Here, we extend that discussion with emphasis on the problems such a solution is bound to face, and conclude that it is ultimately quite unlikely. .

  3. Twin Paradox in de Sitter Spacetime

    CERN Document Server

    Boblest, Sebastian; Wunner, Günter

    2010-01-01

    The "twin paradox" of special relativity offers the possibility to make interstellar flights within a lifetime. For very long journeys with velocities close to the speed of light, however, we have to take into account the expansion of the universe. Inspired by the work of Rindler on hyperbolic motion in curved spacetime, we study the worldline of a uniformly accelerated observer in de Sitter spacetime and the communication between the traveling observer and an observer at rest.

  4. Enjoying Sad Music: Paradox or Parallel Processes?

    Science.gov (United States)

    Schubert, Emery

    2016-01-01

    Enjoyment of negative emotions in music is seen by many as a paradox. This article argues that the paradox exists because it is difficult to view the process that generates enjoyment as being part of the same system that also generates the subjective negative feeling. Compensation theories explain the paradox as the compensation of a negative emotion by the concomitant presence of one or more positive emotions. But compensation brings us no closer to explaining the paradox because it does not explain how experiencing sadness itself is enjoyed. The solution proposed is that an emotion is determined by three critical processes-labeled motivational action tendency (MAT), subjective feeling (SF) and Appraisal. For many emotions the MAT and SF processes are coupled in valence. For example, happiness has positive MAT and positive SF, annoyance has negative MAT and negative SF. However, it is argued that in an aesthetic context, such as listening to music, emotion processes can become decoupled. The decoupling is controlled by the Appraisal process, which can assess if the context of the sadness is real-life (where coupling occurs) or aesthetic (where decoupling can occur). In an aesthetic context sadness retains its negative SF but the aversive, negative MAT is inhibited, leaving sadness to still be experienced as a negative valanced emotion, while contributing to the overall positive MAT. Individual differences, mood and previous experiences mediate the degree to which the aversive aspects of MAT are inhibited according to this Parallel Processing Hypothesis (PPH). The reason for hesitancy in considering or testing PPH, as well as the preponderance of research on sadness at the exclusion of other negative emotions, are discussed.

  5. Cumulative carbon emissions and the Green Paradox

    OpenAIRE

    Ploeg, Frederick Van der

    2013-01-01

    The green paradox states that a gradually more ambitious climate policy such as a renewables subsidy or an anticipated carbon tax induces fossil fuel owners to extract more rapidly and accelerate global warming. However, if extraction becomes more costly as reserves are depleted, such policies also shorten the fossil fuel era, induce more fossil fuel to be left in the earth, and thus curb cumulative carbon emissions. These consequences are relevant, as global warming depends primarily on cumu...

  6. Definite Solution of the Two Capacitors Paradox

    CERN Document Server

    Pankovic, Vladan

    2009-01-01

    In this work we suggest very simple solution of the two capacitors paradox in the completely ideal (without any electrical resistance or inductivity) electrical circuit. Namely, it is shown that electrical field energy loss corresponds to works done by electrical fields of both capacitors by movement of the electrical charge. It is all and nothing more (some dissipative processes, e.g. Joule heating and electromagnetic wave emission effects) is necessary.

  7. Klein Paradox in the Pilot Wave Interpretation

    OpenAIRE

    Dodaro, John F.

    2013-01-01

    The de Broglie-Bohm pilot wave interpretation of quantum mechanics is shown to provide a consistent explanation for a single relativistic particle (more accurately, a single particle process since pair production is addressed). This is accomplished by incorporating the Feynman-Stueckelberg interpretation of anti-matter. The lack of conserved probability and existence of negative energy solutions is studied through this interpretation. We discuss the resolution of Klein's original paradox thro...

  8. Simpson’s Paradox in the interpretation of “leaky pipeline” data

    Directory of Open Access Journals (Sweden)

    Walton Paul H.

    2016-12-01

    Full Text Available The traditional ‘leaky pipeline’ plots are widely used to inform gender equality policy and practice. Herein, we demonstrate how a statistical phenomenon known as Simpson’s paradox can obscure trends in gender ‘leaky pipeline’ plots. Our approach has been to use Excel spreadsheets to generate hypothetical ‘leaky pipeline’ plots of gender inequality within an organisation. The principal factors, which make up these hypothetical plots, can be input into the model so that a range of potential situations can be modelled. How the individual principal factors are then reflected in ‘leaky pipeline’ plots is shown. We find that the effect of Simpson’s paradox on leaky pipeline plots can be simply and clearly illustrated with the use of hypothetical modelling and our study augments the findings in other statistical reports of Simpson’s paradox in clinical trial data and in gender inequality data. The findings in this paper, however, are presented in a way, which makes the paradox accessible to a wide range of people.

  9. The paradox of thrift in an inegalitarian neoclassical economy

    Directory of Open Access Journals (Sweden)

    Mohamed Ben Ridha Mabrouk

    2016-11-01

    Full Text Available Schilcht (1975 and Bourguignon (1981 studied the case of a convex saving function in the Stiglitz (1969 model. They have shown that if one of the two proportions of the rich or the poor is below a certain threshold, there is a two-class equilibrium. However, they have only proved the existence of this threshold. We give here a system of equations to calculate this threshold which we interpret as the maximum proportion of rich for having a stable two-class configuration. If the proportion of rich exceeds this threshold, the economy enters a phase of decline although the golden-rule capital has not yet been reached. The mechanism of this decline recalls the description given in Keynes (1936, of the decline which happens when there is too much savings in an inegalitarian context. This is an example of what is known as the "paradox of thrift". It is remarkable that this paradox takes place in a neoclassical setting that does not include key Keynesian elements such as saturation of demand, monetization of savings, short-term effects, expectation problems, involuntary unemployment and rigidities. Numerical simulations are given to illustrate and analyze the mechanisms involved.

  10. [Once again about "Gregg paradox" and its solution].

    Science.gov (United States)

    Mavrodiev, E V

    2002-01-01

    "Gregg paradox" means that monotypical groups containing the same species (or groups of species) will be equal each other although systematics considers them as different taxa. Thus if the order of placental mammalia Tubilidentata includes one species aardvark Orycteropus after, the order itself, its single family Orycteropodiaceae, single genus of the family Orycteropus and the single species Orycteropus after can be considered as equal to each other. To solve this disagreement the author asserts that taxa of any level can be regarded as an individual according to the taxa of higher rank. Possibility of such interpretation was already suggested by Georg Cantor (1985). He supposed that a set (class) can be regarded as unity by itself. In this case connections between taxa of different levels can be realized by Peano ratio of intrasitive conformities. In this model a genus will consist of species but not individuals, a type--of classes, etc. Thus, if a taxon x as an individual is an element of taxon y, and taxon y as an individual is an element of taxon z, then z according to x will be not only logical class, but class of classes and, hence we could not consider x as an element of z, because the latter consists of indecomposable individual-class y or some similar classes. In this situation "Gregg paradox" does not arise.

  11. Is there a paradox in obesity?

    Science.gov (United States)

    Goyal, Akankasha; Nimmakayala, Kameswara Rao; Zonszein, Joel

    2014-01-01

    In an industrialized society, the increase in obesity incidence has led to an increase in premature morbidity and mortality rates. There is a relationship between body mass index (BMI) and the increased incidence of hypertension, dyslipidemia, type 2 diabetes mellitus, and cardiovascular disease, an increase in mortality. However, obese individuals with these conditions may have better outcomes than their lean counterparts, thus the term "obesity paradox." Most studies supporting this paradox are cross-sectional and do not take into account the quantity or type of adiposity, the disease severity, and comorbidities. Although BMI is an indicator of the amount of body fat, it does not differentiate between adiposity types. Adipocytes that are highly functional have good fuel storage capacity are different from adipocytes found in visceral obesity, which are poorly functioning, laden with macrophages, and causing low-grade inflammation. Individuals with high BMI may be physically fit and have a lower mortality risk when compared with individuals with a lower BMI and poorly functioning adiposity. We review the complexity of adipose tissue and its location, function, metabolic implications, and role in cardiovascular morbidity and mortality. The terminology "obesity paradox" may reflect a lack of understanding of the complex pathophysiology of obesity and the association between adiposity and cardiovascular disease.

  12. Laying the ghost of twin paradox

    Directory of Open Access Journals (Sweden)

    Popović Marko

    2009-01-01

    Full Text Available Someone's true age is not written in his ID, but in his biomarkers. Aging process is not caused by time passing, but by thermodynamically laws. Entropy, extent of metabolic reaction, and temperature are Lorentz invariant, so these facts make twin paradox impossible because there is no way for one twin to age slower than the other even if the time in his frame is dilated. Entropy is the function of state, not time. So as much as standard thermodynamics concerns, the path between two points in space is equivalent to the path between two states. Whether the point B is reached by moving faster using the longer way (with time dilatation, or slower by using shortcut (without time dilatation, the state of the system after completing the road should be the same. This is supported by the fact that when two twins reach the same space-time point (point B in which the state parameters are the same. If we use entropy as an age parameter, then both twins have the same entropy value and are exactly the same biological age. Therefore, the twin paradox is a logical mistake based on wrong first premise. Bergson symmetry is not necessary any more to explain the impossibility of twin paradox.

  13. Obesity and poverty paradox in developed countries

    Directory of Open Access Journals (Sweden)

    Wioletta Żukiewicz-Sobczak

    2014-09-01

    Full Text Available Obesity is a civilization disease and the proportion of people suffering from it continues to grow, especially in the developed countries. Number of obese people in Europe has increased threefold over the last 20 years. The paradox of obesity and poverty relationship is observed especially in the developed and developing countries. In developing countries, along with economic development and income growth, the number of people with overweight and obesity is increasing. This paradox has a relationship with both the easy availability and low cost of highly processed foods containing ‘empty calories’ and no nutritional value. To date, this paradox has been described in the United States and the United Kingdom, although many European countries are also experiencing high percentages of obese people. Among the reasons for the growing obesity in the population of poor people are: higher unemployment, lower education level, and irregular meals. Another cause of obesity is low physical activity, which among the poor is associated with a lack of money for sports equipment. Due to the large rate of deaths caused by diseases directly linked to obesity, the governments of many countries implement prevention programmes of overweight and obesity. These programmes are based primarily on educating the public about a healthy lifestyle based on healthy eating, daily physical activity and avoiding alcohol and cigarettes.

  14. Obesity and poverty paradox in developed countries.

    Science.gov (United States)

    Żukiewicz-Sobczak, Wioletta; Wróblewska, Paula; Zwoliński, Jacek; Chmielewska-Badora, Jolanta; Adamczuk, Piotr; Krasowska, Ewelina; Zagórski, Jerzy; Oniszczuk, Anna; Piątek, Jacek; Silny, Wojciech

    2014-01-01

    Obesity is a civilization disease and the proportion of people suffering from it continues to grow, especially in the developed countries. Number of obese people in Europe has increased threefold over the last 20 years. The paradox of obesity and poverty relationship is observed especially in the developed and developing countries. In developing countries, along with economic development and income growth, the number of people with overweight and obesity is increasing. This paradox has a relationship with both the easy availability and low cost of highly processed foods containing 'empty calories' and no nutritional value. To date, this paradox has been described in the United States and the United Kingdom, although many European countries are also experiencing high percentages of obese people. Among the reasons for the growing obesity in the population of poor people are: higher unemployment, lower education level, and irregular meals. Another cause of obesity is low physical activity, which among the poor is associated with a lack of money for sports equipment. Due to the large rate of deaths caused by diseases directly linked to obesity, the governments of many countries implement prevention programmes of overweight and obesity. These programmes are based primarily on educating the public about a healthy lifestyle based on healthy eating, daily physical activity and avoiding alcohol and cigarettes.

  15. PARADOX SOLUTION ON ELASTIC WEDGE DISSIMILAR MATERIALS

    Institute of Scientific and Technical Information of China (English)

    姚伟岸; 张兵茹

    2003-01-01

    According to the Hellinger-Reissner variational principle and introducing proper transformation of variables, the problem on elastic wedge dissimilar materials can be led to Hamiltonian system, so the solution of the problem can be got by employing the separation of variables method and symplectic eigenfunction expansion under symplectic space, which consists of original variables and their dual variables. The eigenvalue - 1 is a special one of all symplectic eigenvalue for Hamiltonian system in polar coordinate. In general, the eigenvalue - is a single eigenvalue, and the classical solution of an elastic wedge dissimilar materials subjected to a unit concentrated couple at the vertex is got directly by solving the eigenfunction vector for eigenvalue - 1 . But the eigenvalue - 1 becomes a double eigenvalue when the vertex angles and modulus of the materials satisfy certain definite relationships and the classical solution for the stress distribution becomes infinite at this moment, that is, the paradox should occur. Here the Jordan form eigenfunction vector for eigenvalue - 1 exists, and solution of the paradox on elastic wedge dissimilar materials subjected to a unit concentrated couple at the vertex is obtained directly by solving this special Jordan form eigenfunction. The result shows again that the solutions of the special paradox on elastic wedge in the classical theory of elasticity are just Jordan form solutions in symplectic space under Hamiltonian system.

  16. Fermi's paradox: The last challenge for copernicanism?

    Directory of Open Access Journals (Sweden)

    Ćirković M.M.

    2009-01-01

    Full Text Available We review Fermi's paradox (or the 'Great Silence' problem, not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI, but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already more than three quarters of century old puzzle and a quarter of century since the last major review paper in the field by G. David Brin has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built in various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literature on the subject. Finally, we consider the ramifications of various classes of hypotheses for the practical SETI projects. Somewhat paradoxically, it seems that the class of (neocatastrophic hypotheses gives, on the balance, the strongest justification to optimism regarding our current and near-future SETI efforts.

  17. Paradoxical response to dexamethasone and spontaneous hypocortisolism in Cushing's disease.

    Science.gov (United States)

    Lila, Anurag R; Sarathi, Vijaya; Bandgar, Tushar R; Shah, Nalini S

    2013-01-29

    Paradoxical response to dexamethasone and spontaneous development of hypocortisolism are rare features of Cushing's disease. We report a 13-year-old boy with Cushing's disease owing to a pituitary macroadenoma. On initial evaluation, he had partial suppression of serum cortisol by dexamethasone. He developed transient hypocortisolism after first adenomectomy, but the disease recurred after 1 year. Repeat evaluation showed recurrent hypercortisolism and paradoxical response to dexamethasone. He underwent second surgery and, postoperatively, hypercostisolism persisted even after 2 years of surgery. Repeat evaluations after 8 years of second surgery revealed persistent hypocortisolism despite residual tumour of same size and similar plasma adrenocorticotropic hormone (ACTH) levels. We have also shown that the paradoxical increase in serum cortisol was preceded by a paradoxical increase in ACTH. The paradoxical response persisted despite hypocortisolism. This patient with Cushing's disease had two very rare features: paradoxical response to dexamethasone and spontaneous development of hypocortisolism.

  18. International Capital Markets, Oil Producers and the Green Paradox

    OpenAIRE

    van der Meijden, Gerard C.; van der Ploeg, Rick; Cees A. Withagen

    2014-01-01

    In partial equilibrium a rapidly rising carbon tax encourages oil producers to extract fossil fuels more quickly, giving rise to the Green Paradox. General equilibrium analysis for a closed economy shows that a rapidly rising carbon tax negatively affects the interest rate, which tends to weaken the Green Paradox. However, in a two-country world with an oil-importing and an oil-exporting region the Green Paradox may be amplified in general equilibrium if exporters are relatively patient. On t...

  19. Psychohistory Paradox and Introduction to Quantum Social Science

    OpenAIRE

    Wayne, James J.

    2014-01-01

    Why would social science need the help from quantum mechanics? First, there are many unanswerable questions in social science. Are financial markets predictable? How to predict the financial markets? These important questions are not answerable in the existing framework of finance or economics. One important paradox in social science is the psychohistory paradox proposed by Asimov. In his novels, Asimov highlighted a paradox of human society: if the future events of a human society are predic...

  20. Psychohistory Paradox and Introduction to Quantum Social Science

    OpenAIRE

    2014-01-01

    Why would social science need the help from quantum mechanics? First, there are many unanswerable questions in social science. Are financial markets predictable? How to predict the financial markets? These important questions are not answerable in the existing framework of finance or economics. One important paradox in social science is the psychohistory paradox proposed by Asimov. In his novels, Asimov highlighted a paradox of human society: if the future events of a human society are predic...

  1. A paradox of cumulative culture.

    Science.gov (United States)

    Kobayashi, Yutaka; Wakano, Joe Yuichiro; Ohtsuki, Hisashi

    2015-08-21

    Culture can grow cumulatively if socially learnt behaviors are improved by individual learning before being passed on to the next generation. Previous authors showed that this kind of learning strategy is unlikely to be evolutionarily stable in the presence of a trade-off between learning and reproduction. This is because culture is a public good that is freely exploited by any member of the population in their model (cultural social dilemma). In this paper, we investigate the effect of vertical transmission (transmission from parents to offspring), which decreases the publicness of culture, on the evolution of cumulative culture in both infinite and finite population models. In the infinite population model, we confirm that culture accumulates largely as long as transmission is purely vertical. It turns out, however, that introduction of even slight oblique transmission drastically reduces the equilibrium level of culture. Even more surprisingly, if the population size is finite, culture hardly accumulates even under purely vertical transmission. This occurs because stochastic extinction due to random genetic drift prevents a learning strategy from accumulating enough culture. Overall, our theoretical results suggest that introducing vertical transmission alone does not really help solve the cultural social dilemma problem. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. The Paradox of the Fuzzy Disambiguation in the Information Retrieval

    Directory of Open Access Journals (Sweden)

    Anna Bryniarska

    2013-09-01

    Full Text Available Current methods of data mining, word sense disambiguation in the information retrieval, semantic relation, fuzzy sets theory, fuzzy description logic, fuzzy ontology and their implementation, omit the existence of paradox called here the paradox of the fuzzy disambiguation. The paradox lies in the fact that due to fuzzy data and the experts knowledge it can be obtained precise knowledge. In this paper to describe this paradox, is introduced a conceptual apparatus. Moreover, there is formulated an information retrieval logic. There are suggested certain applications of this logic to search information on the Web.

  3. Paradox of simple limiter control.

    Science.gov (United States)

    Hilker, Frank M; Westerhoff, Frank H

    2006-05-01

    Chaos control by simple limiters is an easy-to-implement and effective method of stabilizing irregular fluctuations. Here we show that applying limiter control to a state variable can significantly shift its mean value. In many situations, this is a countereffective as well as unexpected result, when the aim of control is also to restrict the dynamics. We discuss this effect on the basis of a model of population dynamics and conclude that it can have severe implications for the management of pest species and epidemic spread.

  4. What the liar paradox can reveal about the quantum logical structure of our minds

    CERN Document Server

    Bieberich, E

    2001-01-01

    In human consciousness perceptions are distinct or atomistic events despite being perceived by an apparently undivided inner observer. This paper applies both classical (Boolean) and quantum logic to analysis of the Liar paradox which is taken as a typical example of a self-referential negation in the perception space of an undivided observer. The conception of self-referential paradoxes is a unique ability of the human mind still lacking an explanation on the basis of logic. It will be shown that both classical and quantum logics fail to resolve the paradox because of the particle-like (atomistic) nature of physical events in the moments of perception. I suggest a physical mechanism that can deal with our experience of self-referential paradox. Because it is also shown that this cannot be achieved by any previously suggested classical or quantum mechanical operation, the newly proposed mechanism provides a better model than others for an important aspect of the structure of our minds.

  5. Unintended consequence of managing the coupled humans and water: the irrigation efficiency paradox

    Science.gov (United States)

    Liu, Y.

    2015-12-01

    Water shortage most severely restricts the socio-economic development of many arid and semi-arid regions in the world, for which water-saving technology is believed to be an effective solution. However, as a realworld case, the total water consumption of Xinjiang Uygur Autonomous Region of China continued to increase as irrigation efficiency dramatically improved through the application of water-saving technology in the study period 1998-2010. This phenomenon, known as the irrigation efficiency paradox or Jevons paradox, is interpreted as an economic rebound effect. In this study, we explore the dynamic feedbacks between humans and water in this paradox through a socio-hydrological perspective. We analyze the co-evolutionary trajectory of coupled human-water dynamics from 1950 to 2010 to provide it a general context. A conceptual socio-hydrological model based on five key elements, namely, irrigation land, water-saving technology, water consumption, societal sensitivity to water scarcity, and the policy mix, is constructed. The policy mix to be adopted is determined by a social decision-making process mainly based on the societal sensitivity, which reflects the societal preference on two sorts of policies: (i) irrigation land control and (ii) water-saving technology promotion. Modeling results verify the hypothesized mechanism by successfully reproducing the observed dynamics including the emergence of the efficiency paradox. Our analysis indicates that the implementation of more adaptive rules may even eliminate the paradox. The effects of different initial policy mixes are also explored, and the results show that land control policies should be given equal priority when dealing with water scarcity. These findings point to a double-helix-type co-evolution of humans and water.

  6. The paradox of strategic environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    Bidstrup, Morten, E-mail: bidstrup@plan.aau.dk; Hansen, Anne Merrild, E-mail: merrild@plan.aau.dk

    2014-07-01

    Strategic Environmental Assessment (SEA) is a tool that can facilitate sustainable development and improve decision-making by introducing environmental concern early in planning processes. However, various international studies conclude that current planning practice is not taking full advantage of the tool, and we therefore define the paradox of SEA as the methodological ambiguity of non-strategic SEA. This article explores causality through at three-step case study on aggregates extraction planning in Denmark, which consists of a document analysis; a questionnaire survey and follow-up communication with key planners. Though the environmental reports on one hand largely lack strategic considerations, practitioners express an inherent will for strategy and reveal that their SEAs in fact have been an integrated part of the planning process. Institutional context is found to be the most significant barrier for a strategy and this suggests that non-strategic planning setups can prove more important than non-strategic planning in SEA practice. Planners may try to execute strategy within the confinements of SEA-restricted planning contexts; however, such efforts can be overlooked if evaluated by a narrow criterion for strategy formation. Consequently, the paradox may also spark from challenged documentation. These findings contribute to the common understanding of SEA quality; however, further research is needed on how to communicate and influence the strategic options which arguably remain inside non-strategic planning realities. - Highlights: • International studies conclude that SEAs are not strategic. = The paradox of SEA. • Even on the highest managerial level, some contexts do not leave room for strategy. • Non-strategic SEA can derive from challenged documentation. • Descriptive and emergent strategy formation can, in practice, be deemed non-strategic.

  7. Vitamin paradox in obesity: Deficiency or excess?

    Science.gov (United States)

    Zhou, Shi-Sheng; Li, Da; Chen, Na-Na; Zhou, Yiming

    2015-08-25

    Since synthetic vitamins were used to fortify food and as supplements in the late 1930s, vitamin intake has significantly increased. This has been accompanied by an increased prevalence of obesity, a condition associated with diabetes, hypertension, cardiovascular disease, asthma and cancer. Paradoxically, obesity is often associated with low levels of fasting serum vitamins, such as folate and vitamin D. Recent studies on folic acid fortification have revealed another paradoxical phenomenon: obesity exhibits low fasting serum but high erythrocyte folate concentrations, with high levels of serum folate oxidation products. High erythrocyte folate status is known to reflect long-term excess folic acid intake, while increased folate oxidation products suggest an increased folate degradation because obesity shows an increased activity of cytochrome P450 2E1, a monooxygenase enzyme that can use folic acid as a substrate. There is also evidence that obesity increases niacin degradation, manifested by increased activity/expression of niacin-degrading enzymes and high levels of niacin metabolites. Moreover, obesity most commonly occurs in those with a low excretory reserve capacity (e.g., due to low birth weight/preterm birth) and/or a low sweat gland activity (black race and physical inactivity). These lines of evidence raise the possibility that low fasting serum vitamin status in obesity may be a compensatory response to chronic excess vitamin intake, rather than vitamin deficiency, and that obesity could be one of the manifestations of chronic vitamin poisoning. In this article, we discuss vitamin paradox in obesity from the perspective of vitamin homeostasis.

  8. Paradox of enrichment and system order reduction: bacteriophages dynamics as case study.

    Science.gov (United States)

    Korobeinikov, Andrei; Shchepakina, Elena; Sobolev, Vladimir

    2016-09-01

    The paradox of enrichment in a 3D model for bacteriophage dynamics, with a free infection stage of the phage and a bilinear incident rate, is considered. An application of the technique of singular perturbation theory allows us to demonstrate why the paradox arises in this 3D model despite the fact that it has a bilinear incident rate (while in 2D predator-prey models it is usually associated with the concavity of the attack rate). Our analysis demonstrates that the commonly applied approach of the model order reduction using the so-called quasi-steady-state approximation can lead to a loss of important properties of an original system. © The authors 2015. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

  9. Superlubricity: A Paradox about Confined Fluids Resolved

    Science.gov (United States)

    Zhu, Yingxi; Granick, Steve

    2004-08-01

    Using the method of Frantz and Salmeron to cleave mica [Tribol. Lett.TRLEFS1023-8883 5, 151 (1998)10.1023/A:1019149910047] we investigate alkane fluids in a surface forces apparatus and confirm several predictions of molecular dynamics (MD) simulation. An oscillatory force-distance profile is observed for the methyl-branched alkane, squalane. Boundary slip is inferred from the frictional sliding of molecularly thin fluids and also from the hydrodynamic flow of thicker films. These findings resolve the paradox that prior experiments disagreed with these aspects of MD predictions, and demonstrate that exceptionally low energy dissipation is possible when fluids move past solid surfaces that are sufficiently smooth.

  10. Obesity paradox, cachexia, frailty, and heart failure.

    Science.gov (United States)

    Lavie, Carl J; De Schutter, Alban; Alpert, Martin A; Mehra, Mandeep R; Milani, Richard V; Ventura, Hector O

    2014-04-01

    Overweight and obesity adversely affect cardiovascular (CV) risk factors and CV structure and function, and lead to a marked increase in the risk of developing heart failure (HF). Despite this, an obesity paradox exists, wherein those who are overweight and obese with HF have a better prognosis than their leaner counterparts, and the underweight, frail, and cachectic have a particularly poor prognosis. In light of this, the potential benefits of exercise training and efforts to improve cardiorespiratory fitness, as well as the potential for weight reduction, especially in severely obese patients with HF, are discussed.

  11. The information paradox: Conflicts and resolutions

    Indian Academy of Sciences (India)

    Samir D Mathur

    2012-11-01

    Many relativists have been long convinced that black hole evaporation leads to information loss or remnants. String theorists have however not been too worried about the issue, largely due to a belief that the Hawking argument for information loss is flawed in its details. A recently derived inequality shows that the Hawking argument for black holes with horizon can in fact be made rigorous. What happens instead is that in string theory, black hole microstates have no horizons. Thus the evolution of radiation quanta with $E ∼ kT$ is modified by order unity at the horizon, and we resolve the information paradox.

  12. The "paradox" of a brake pad

    Science.gov (United States)

    Zhuravlev, V. Ph.

    2017-05-01

    By the example of a brake pad, a typical error is illustrated, i.e., the fact that the initial conditions should be reconsidered upon finding that there is no solution of the static problem in a certain region of parameters (incorrect in the sense of Hadamard). For example, it turns out that the conditions of disk rotation in the positive direction cannot be implemented in the domain of parameters leading to a "paradox." In this region, the "brake-pad" mechanism is transformed into the "wedge stopper" mechanism.

  13. O paradoxo de Chalmers Chalmers' paradox

    Directory of Open Access Journals (Sweden)

    Gustavo Leal-Toledo

    2009-01-01

    Full Text Available O Argumento dos Zumbis proposto por Chalmers, ao contrário de defender o dualismo, bane as qualia para um "mundo" onde elas não podem influenciar o julgamento que fazemos sobre nós mesmos. Por este motivo, pelo próprio argumento, podemos ser um zumbi e não saber. A isso Chalmers chamou de The Paradox of Phenomenal Judgment. O problema é que ele aceita tal paradoxo como parte de sua própria teoria. No entanto, este movimento filosófico não é aceitável e este paradoxo mina a teoria de Chalmers por dentro mostrando que o argumento dos zumbis é, na verdade, um argumento contra o dualismo. Chalmers tenta resolver este problema com uma série de argumentos que tem como base o fato de que a consciência é um bruto explanandum indubitável. No entanto, tal tentativa fracassa por uma série de razões que mostram que mesmo se ele estivesse correto, ainda poderíamos ser um zumbi e não saber.The Zombie Argument proposed by Chalmers, instead of working as a defense of dualism, banishes qualia to a 'world' where they cannot influence our judgments about ourselves. For this reason, according to the argument itself, we may be all zombies and not know it. This is what Chalmers called The Paradox of Phenomenal Judgment. The problem is that he accepts this paradox as part of his theory. This philosophical move, however, is not acceptable, for the paradox undermines Chalmers' theory, by showing that the zombie argument is, actually, an argument against dualism. Chalmers tries to solve this problem with many arguments based on the status of consciousness as brute indubitable explanandum. However, this attempt is a failure by a series of reasons showing that, even if he were right, we could still be zombies and not know it.

  14. Time, physics, and the paradoxes of continuity

    CERN Document Server

    Steinberg, D A

    2003-01-01

    A recent article in this journal proposes a radical reformulation of classical and quantum dynamics based on a perceived deficiency in current definitions of time. The argument is incorrect but the errors highlight aspects of the foundations of mathematics and physics that are commonly confused and misunderstood. For this reason, the article provides an important and heuristic opportunity to reexamine the types of time and non-standard analysis. This paper will discuss the differences between physical time and experiential time and explain how an expanded system of real analysis containing infinitesimals can resolve the paradoxes of continuity without sacrificing the modern edifice of mathematical physics.

  15. Collective decision making and paradoxical games

    CERN Document Server

    Parrondo, J M R; García-Toraño, E; Sotillo, B

    2014-01-01

    We study an ensemble of individuals playing the two games of the so-called Parrondo paradox. In our study, players are allowed to choose the game to be played by the whole ensemble in each turn. The choice cannot conform to the preferences of all the players and, consequently, they face a simple frustration phenomenon that requires some strategy to make a collective decision. We consider several such strategies and analyze how fluctuations can be used to improve the performance of the system.

  16. Impossible folding puzzles and other mathematical paradoxes

    CERN Document Server

    Sarcone, Gianni A

    2014-01-01

    Do all problems have solutions? Is complexity synonymous with difficulty? This original collection of mathematical puzzles and paradoxes proves that things aren't always what they seem! Readers will discover that nothing is as easy or as difficult as it looks and that puzzles can have one, several, or no solutions.The fun-filled puzzles begin with The Tricky Hole, a challenge that involves pushing a large coin through a small hole in a sheet of paper without ripping or making any cuts in the paper. Advance to the Elastic Playing Card, in which it's possible to cut a hole into a playing card bi

  17. Once Again About the Klein Paradox

    CERN Document Server

    Kevlishvili, N; Nadareishvili, T P

    2003-01-01

    After a short survey of the Klein Paradox in 3-dimensional relativistic equations, there is a detailed consideration of Dirac modified equation, which follows by one particle overweighting. It is shown, that the spin-orbital coupling is excluded in this equation as a result of pseudospin symmetry. That is why the separation of variables and reduction to radial equation is possible with standard methods in momentum space. The kernel of obtained radial equation differs from the kernel of spinless Salpeter equation in bounded, regular factor. That is why the equation has confinement type solutions.

  18. Application Neutrality and a Paradox of Side Payments

    CERN Document Server

    Altman, Eitan; Kesidis, George

    2010-01-01

    The ongoing debate over "net neutrality" covers a broad set of issues related to the regulation of public networks. This paper contains two separate contributions: (a) an extension of the quadratic-utility framework we proposed in a previous paper to study the impact of side payments in a system involving pluralities of access and content providers; and (b) a variation of this model to deal with the question of application neutrality. Our analysis of the generalized framework (a) reveals an interesting "paradox" that did not occur with monopolistic players: side payments handicap the providers who perceive them. Application neutrality (b) refers to price discrimination: ISPs charging consumers different fees depending on their use of the network (web surfing, VoIP, file sharing, etc.). We analyze the consequences of such discrimination for a simple two-application setting.

  19. Paradox reconsidered: Methane oversaturation in well-oxygenated lake waters

    DEFF Research Database (Denmark)

    Tang, Kam W.; McGinnis, Daniel F.; Frindte, Katharina

    2014-01-01

    was up to 5 mmol m22 d21. Mid-water methane oversaturation was also observed in nine other lakes that collectively showed a strongly negative gradient of methane concentration within 0–20% dissolved oxygen (DO) in the bottom water, and a positive gradient within ≥20% DO in the upper water column. Further......The widely reported paradox of methane oversaturation in oxygenated water challenges the prevailing paradigm that microbial methanogenesis only occurs under anoxic conditions. Using a combination of field sampling, incubation experiments, and modeling, we show that the recurring mid-water methane...... peak in Lake Stechlin, northeast Germany, was not dependent on methane input from the littoral zone or bottom sediment or on the presence of known micro-anoxic zones. The methane peak repeatedly overlapped with oxygen oversaturation in the seasonal thermocline. Incubation experiments and isotope...

  20. Paradoxical pop-ups: Why are they difficult to catch?

    Science.gov (United States)

    McBeath, Michael K.; Nathan, Alan M.; Bahill, A. Terry; Baldwin, David G.

    2008-08-01

    Professional baseball players occasionally find it difficult to gracefully approach seemingly routine pop-ups. We describe a set of towering pop-ups with trajectories that exhibit cusps and loops near the apex. For a normal fly ball the horizontal velocity continuously decreases due to drag caused by air resistance. For pop-ups the Magnus force is larger than the drag force. In these cases the horizontal velocity initially decreases like a normal fly ball, but after the apex, the Magnus force accelerates the horizontal motion. We refer to this class of pop-ups as paradoxical because they appear to misinform the typically robust optical control strategies used by fielders and lead to systematic vacillation in running paths, especially when a trajectory terminates near the fielder. Former major league infielders confirm that our model agrees with their experiences.

  1. The earth as a planet - Paradigms and paradoxes

    Science.gov (United States)

    Anderson, D. L.

    1984-01-01

    The independent growth of the various branches of the earth sciences in the past two decades has led to a divergence of geophysical, geochemical, geological, and planetological models for the composition and evolution of a terrestrial planet. Evidence for differentiation and volcanism on small planets and a magma ocean on the moon contrasts with hypotheses for a mostly primitive, still undifferentiated, and homogeneous terrestrial mantle. In comparison with the moon, the earth has an extraordinarily thin crust. The geoid, which should reflect convection in the mantle, is apparently unrelated to the current distribution of continents and oceanic ridges. If the earth is deformable, the whole mantle should wander relative to the axis of rotation, but the implications of this are seldom discussed. The proposal of a mantle rich in olivine violates expectations based on evidence from extraterrestrial sources. These and other paradoxes force a reexamination of some long-held assumptions.

  2. The Neutrosophic Logic View to Schroedinger's Cat Paradox

    Directory of Open Access Journals (Sweden)

    Smarandache F.

    2006-04-01

    Full Text Available This article discusses Neutrosophic Logic interpretation of the Schrodinger's cat paradox. We argue that this paradox involves some degree of indeterminacy (unknown which Neutrosophic Logic could take into consideration, whereas other methods including Fuzzy Logic could not. For a balanced discussion, other interpretations have also been discussed.

  3. The Lottery Paradox and the Pragmatics of Belief

    NARCIS (Netherlands)

    Douven, Igor

    The thesis that high probability suffices for rational belief, while initially plausible, is known to face the Lottery Paradox. The present paper proposes an amended version of that thesis which escapes the Lottery Paradox. The amendment is argued to be plausible on independent grounds.

  4. Killing Mosquitoes and Keeping Practice: Teacher Education as Sustaining Paradox

    Science.gov (United States)

    Keiser, David Lee

    2013-01-01

    The moral and ethical charge of teaching and teacher education includes sustaining equanimity and paradox, and maintaining poise amongst contradicting policies and interests. This paper draws upon the wisdom of the Tao Te Ching to address some paradoxes in education and teacher preparation. Specifically, the article looks at four chapters of the…

  5. [Reviews of "Dewey, Peirce, and the Learning Paradox"].

    Science.gov (United States)

    Apple, Michael W.; Noddings, Nel; Gee, James Paul; Cunningham, Michael; Russell, Dee; Cherryholmes, Cleo H.; Pekarsky, Daniel

    1999-01-01

    Seven articles comment on the proposed resolution of the "learning paradox" of how people make meaning and learn from prior learning. The reviewers find much of merit in the proposed reliance on the work of J. Dewey and C. Peirce, but they criticize many aspects of the paper, especially its brief treatment of the learning paradox itself. (SLD)

  6. An Applet for the Investigation of Simpson's Paradox

    Science.gov (United States)

    Schneiter, Kady; Symanzik, Jurgen

    2013-01-01

    This article describes an applet that facilitates investigation of Simpson's Paradox in the context of a number of real and hypothetical data sets. The applet builds on the Baker-Kramer graphical representation for Simpson's Paradox. The implementation and use of the applet are explained. This is followed by a description of how the applet has…

  7. The "Paradox of Interdisciplinarity" in Australian Research Governance

    Science.gov (United States)

    Woelert, Peter; Millar, Victoria

    2013-01-01

    This paper identifies what can be called the "paradox of interdisciplinarity" (Weingart 2000) in Australian higher education research governance and explores some of its constitutive dimensions. In the Australian context, the paradox of interdisciplinarity primarily concerns the proliferation of a programmatic discourse of…

  8. A Simple Explanation of the Classic Hydrostatic Paradox

    Science.gov (United States)

    Kontomaris, Stylianos-Vasileios; Malamou, Anna

    2016-01-01

    An interesting problem in fluid mechanics, with significant educational importance, is the classic hydrostatic paradox. The hydrostatic paradox states the fact that in different shaped containers, with the same base area, which are filled with a liquid of the same height, the applied force by the liquid on the base of each container is exactly the…

  9. Killing Mosquitoes and Keeping Practice: Teacher Education as Sustaining Paradox

    Science.gov (United States)

    Keiser, David Lee

    2013-01-01

    The moral and ethical charge of teaching and teacher education includes sustaining equanimity and paradox, and maintaining poise amongst contradicting policies and interests. This paper draws upon the wisdom of the Tao Te Ching to address some paradoxes in education and teacher preparation. Specifically, the article looks at four chapters of the…

  10. A Comparison of Paradoxical and Nonparadoxical Interpretations and Directives.

    Science.gov (United States)

    Feldman, Daniel A.; And Others

    1982-01-01

    Explored the effects of consistent and inconsistent combinations of paradoxical and nonparadoxical interpretations and directives in brief counseling with moderately depressed college students. Paradoxical interpretations were associated with more symptom remission than were nonparadoxical interpretations. The nature of the directives students…

  11. Feynman's Relativistic Electrodynamics Paradox and the Aharonov-Bohm Effect

    Science.gov (United States)

    Caprez, Adam; Batelaan, Herman

    2009-03-01

    An analysis is done of a relativistic paradox posed in the Feynman Lectures of Physics involving two interacting charges. The physical system presented is compared with similar systems that also lead to relativistic paradoxes. The momentum conservation problem for these systems is presented. The relation between the presented analysis and the ongoing debates on momentum conservation in the Aharonov-Bohm problem is discussed.

  12. The "Paradox of Interdisciplinarity" in Australian Research Governance

    Science.gov (United States)

    Woelert, Peter; Millar, Victoria

    2013-01-01

    This paper identifies what can be called the "paradox of interdisciplinarity" (Weingart 2000) in Australian higher education research governance and explores some of its constitutive dimensions. In the Australian context, the paradox of interdisciplinarity primarily concerns the proliferation of a programmatic discourse of…

  13. A paradox in the global description of the multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Bousso, Raphael [Center for Theoretical Physics, Department of Physics, University of California, Berkeley, CA 94720-7300 (United States); Freivogel, Ben [Center for Theoretical Physics, Department of Physics, University of California, Berkeley, CA 94720-7300 (United States)

    2007-06-15

    We use an argument by Page to exhibit a paradox in the global description of the multiverse: the overwhelming majority of observers arise from quantum fluctuations and not by conventional evolution. Unless we are extremely atypical, this contradicts observation. The paradox does not arise in the local description of the multiverse, but similar arguments yield interesting constraints on the maximum lifetime of metastable vacua.

  14. Bolzano's Approach to the Paradoxes of Infinity: Implications for Teaching

    Science.gov (United States)

    Waldegg, Guillermina

    2005-01-01

    In this paper we analyze excerpts of "Paradoxes of the Infinite", the posthumous work of Bernard Bolzano (1781-1848), in order to show that Georg Cantor's (1845-1918) approach to the problem of defining actual mathematical infinity is not the most natural. In fact, Bolzano's approach to the paradoxes of infinity is more intuitive, while remaining…

  15. Lord’s Paradox Revisited - (On Lord! Kumbaya!)

    Science.gov (United States)

    2014-10-03

    Here, Lord’s paradox has surfaced through a variant named the Birth Weight paradox, which presents a new twist . Whereas in Lord’s setup we faced a...research. PLOS One 9 artikel nr e95949. Fisher, R. (1935). The Design of Experiments. Oliver and Boyd, Edinburgh. Frangakis, C. and Rubin, D. (2002

  16. On the empirical relevance of Condorcet’s paradox

    NARCIS (Netherlands)

    Deemen, A.M.A. van

    2014-01-01

    Condorcet’s paradox occurs when there is no alternative that beats every other alternative by majority. The paradox may pose real problems to democratic decision making such as decision deadlocks and democratic paralysis. However, its relevance has been discussed again and again since the celebrated

  17. A Simple Explanation of the Classic Hydrostatic Paradox

    Science.gov (United States)

    Kontomaris, Stylianos-Vasileios; Malamou, Anna

    2016-01-01

    An interesting problem in fluid mechanics, with significant educational importance, is the classic hydrostatic paradox. The hydrostatic paradox states the fact that in different shaped containers, with the same base area, which are filled with a liquid of the same height, the applied force by the liquid on the base of each container is exactly the…

  18. Pulmonary embolism and impending paradoxical embolism: a case report

    Institute of Scientific and Technical Information of China (English)

    ZHONG You; HE Qing; WANG Xin-yue; CHEN Huan; LI Jing; ZHEN Wen-jun; TONG Hong-feng; WANG Huai-bin; CHEN Qi-hang

    2008-01-01

    @@ Adefinitive diagnosis of paradoxical embolism is based on the evidence that a thrombus crosses through the right-to-left shunting. We report a case of impending paradoxical embolism in a patient with pulmonary embolism diagnosed by echocardiography and proved by operation later.

  19. The Lottery Paradox and the Pragmatics of Belief

    NARCIS (Netherlands)

    Douven, Igor

    2012-01-01

    The thesis that high probability suffices for rational belief, while initially plausible, is known to face the Lottery Paradox. The present paper proposes an amended version of that thesis which escapes the Lottery Paradox. The amendment is argued to be plausible on independent grounds.

  20. Glutamate protects against Ca(2+) paradox-induced injury and inhibits calpain activity in isolated rat hearts.

    Science.gov (United States)

    Zhang, Jian-Ying; Kong, Ling-Heng; Lai, Dong; Jin, Zhen-Xiao; Gu, Xiao-Ming; Zhou, Jing-Jun

    2016-10-01

    This study determined the effects of glutamate on the Ca(2+) paradoxical heart, which is a model for Ca(2+) overload-induced injury during myocardial ischaemia and reperfusion, and evaluated its effect on a known mediator of injury, calpain. An isolated rat heart was retrogradely perfused in a Langendorff apparatus. Ca(2+) paradox was elicited via perfusion with a Ca(2+) -free Krebs-Henseleit (KH) solution for 3 minutes followed by Ca(2+) -containing normal KH solution for 30 minutes. The Ca(2+) paradoxical heart exhibited almost no viable tissue on triphenyltetrazolium chloride staining and markedly increased LDH release, caspase-3 activity, cytosolic cytochrome c content, and apoptotic index. These hearts also displayed significantly increased LVEDP and a disappearance of LVDP. Glutamate (5 and 20 mmol/L) significantly alleviated Ca(2+) paradox-induced injury. In contrast, 20 mmol/L mannitol had no effect on Ca(2+) paradox. Ca(2+) paradox significantly increased the extent of the translocation of μ-calpain to the sarcolemmal membrane and the proteolysis of α-fodrin, which suggests calpain activation. Glutamate also blocked these effects. A non-selective inhibitor of glutamate transporters, dl-TBOA (10 μmol/L), had no effect on control hearts, but it reversed glutamate-induced cardioprotection and reduction in calpain activity. Glutamate treatment significantly increased intracellular glutamate content in the Ca(2+) paradoxical heart, which was also blocked by dl-TBOA. We conclude that glutamate protects the heart against Ca(2+) overload-induced injury via glutamate transporters, and the inhibition of calpain activity is involved in this process. © 2016 John Wiley & Sons Australia, Ltd.

  1. Explaining the Energy-Efficiency Paradox. A Vintage Model with Returns to Diversity and Learning-by-Using: A Vintage model with returns to diversity and learning-by-using

    NARCIS (Netherlands)

    H.L.F. de Groot (Henri); M.W. Hofkes; P. Mulder (Peter)

    2003-01-01

    textabstractThis paper studies the adoption and diffusion of energy-saving technologies in a vintage model. An important characteristic of the model is that vintages are modeled as being complementary: there are returns to diversity of using different vintages. We analyse how diffusion patterns and

  2. Avoiding the "Condorcet paradox" in stakeholder networks for participatory decision-making: an agent-based approach

    CERN Document Server

    Pira, Michela Le; Ignaccolo, Matteo; Pluchino, Alessandro; Rapisarda, Andrea

    2016-01-01

    We address the problem of a participatory decision-making process where a shared priority list of alternatives has to be obtained while avoiding inconsistent decisions, related to the "Condorcet paradox". An agent-based model (ABM) is proposed to mimic this process in different social networks of stakeholders who interact according to an opinion dynamics model. Simulations' results show the efficacy of interaction in avoiding the paradox and finding a transitive and, above all, shared decision. These findings are in agreement with real participation experiences regarding transport planning decisions and can give useful suggestions on how to plan an effective participation process for sustainable policy-making based on opinion consensus.

  3. The Hispanic paradox in cardiovascular disease and total mortality.

    Science.gov (United States)

    Medina-Inojosa, Jose; Jean, Nathalie; Cortes-Bergoderi, Mery; Lopez-Jimenez, Francisco

    2014-01-01

    Health statistics and epidemiologic studies have shown that Hispanics live longer than Non Hispanic Whites, despite a high prevalence of cardiovascular disease (CVD) risk factors and an average low socioeconomic status, both strong predictors of CVD and mortality. This phenomenon has been dubbed "The Hispanic paradox" and has been demonstrated in old and contemporary cohorts. To date, no factor has been identified that could explain this phenomenon, but socio demographic factors, dietary intake and genetic predisposition have been proposed as possible explanations for the Hispanic paradox. As with the French paradox, where French were found to have a lower rate of coronary heart disease (CHD), helped to identify the role of the Mediterranean diet and wine consumption in the prevention of CHD, the Hispanic paradox could help identify protective factors against CHD. This article describes the current evidence supporting the existence of the Hispanic paradox and provides a brief review on the possible explanations. Copyright © 2014. Published by Elsevier Inc.

  4. Obesity Paradox in the Course of Cerebrovascular Diseases.

    Science.gov (United States)

    Brzecka, Anna; Ejma, Maria

    2015-01-01

    Obesity remains an important risk factor of cardiovascular and cerebrovascular diseases. However, it has been observed that increased body fat and body mass index predicted longer survival after the occurrence of a cardiovascular event. This observation has been named the obesity paradox. Initially, the term obesity paradox referred to the observation of the better outcome of cardiovascular diseases, such as heart failure and coronary heart disease, in obese patients as compared to underweight and normal-weight patients. Recently, similar, although fewer, observations confirm the occurrence of the obesity paradox in patients with acute cerebrovascular diseases. The underlying reasons for the protective effects of excessive body fat tissue against the consequences of acute cardiovascular and cerebrovascular diseases are poorly understood. The effect of preconditioning may be associated with the obesity paradox. The issue of the correlation between obesity and better survival of patients with cardiovascular and cerebrovascular diseases still remains largely unexplored. Debates for and against the obesity paradox continue.

  5. Unveiling consumer's privacy paradox behaviour in an economic exchange.

    Science.gov (United States)

    Motiwalla, Luvai F; Li, Xiao-Bai

    2016-01-01

    Privacy paradox is of great interest to IS researchers and firms gathering personal information. It has been studied from social, behavioural, and economic perspectives independently. However, prior research has not examined the degrees of influence these perspectives contribute to the privacy paradox problem. We combine both economic and behavioural perspectives in our study of the privacy paradox with a price valuation of personal information through an economic experiment combined with a behavioural study on privacy paradox. Our goal is to reveal more insights on the privacy paradox through economic valuation on personal information. Results indicate that general privacy concerns or individual disclosure concerns do not have a significant influence on the price valuation of personal information. Instead, prior disclosure behaviour in specific scenario, like with healthcare providers or social networks, is a better indicator of consumer price valuations.

  6. Is There a Paradox in Obesity?

    Science.gov (United States)

    Goyal, Akankasha; Nimmakayala, Kameswara Rao; Zonszein, Joel

    2014-01-01

    In an industrialized society, the increase in obesity incidence has led to an increase in premature morbidity and mortality rates. There is a relationship between body mass index (BMI) and the increased incidence of hypertension, dyslipidemia, type 2 diabetes, and cardiovascular disease, leading to mortality. However, obese individuals with these conditions may have better outcomes than their lean counterparts, thus the term “obesity paradox.” Most studies supporting this paradox are cross-sectional and do not take into account the quantity or type of adiposity, the disease severity and comorbidities. While BMI is an indicator of the amount of body fat, it does not differentiate between adiposity types. Adipocytes that are highly functional and have good fuel storage capacity are different from adipocytes found in visceral obesity, which are poorly functioning, laden with macrophages and causing low grade inflammation. Individuals with high BMI may be physically fit and have a lower mortality risk when compared to individuals with a lower BMI and poorly functioning adiposity. We review the complexity of adipose tissue as well as its location, function, metabolic implications and role in cardiovascular morbidity and mortality. The terminology ‘obesity paradox’ may reflect a lack of understanding of the complex pathophysiology of obesity and the association between adiposity and cardiovascular disease. PMID:24896249

  7. The Obesity Paradox and Cardiorespiratory Fitness

    Directory of Open Access Journals (Sweden)

    Paul A. McAuley

    2012-01-01

    Full Text Available Cardiorespiratory fitness as an explanation for the obesity paradox warrants further examination. We evaluated independent and joint associations of cardiorespiratory fitness and adiposity with all-cause mortality in 811 middle-aged (age, 53.3±7.2 years male never smokers without documented cardiopulmonary disease or diabetes from the Veterans Exercise Testing Study (VETS. Cardiorespiratory fitness was quantified in metabolic equivalents (METs using final treadmill speed and grade achieved on a maximal exercise test. Subjects were grouped for analysis by METs: unfit (lowest third and fit (upper two-thirds; and by body mass index (kg/m2: nonobese (18.5−29.9 and obese (≥30.0. Associations of baseline fitness and adiposity measures with all-cause mortality were determined by Cox proportional hazards analysis adjusted for age, ethnicity, hypertension, hypercholesterolemia, family history of coronary artery disease, and cardiovascular medication use. In multivariate analysis, mortality risk for obese/fit men did not differ significantly from the nonobese/fit reference group. However, compared to the reference group, nonobese and obese unfit men were 2.2 (=0.01 and 1.9 (=0.03 times more likely to die, respectively. Cardiorespiratory fitness altered the obesity paradox such that mortality risk was lower for both obese and nonobese men who were fit.

  8. Fermi's Paradox - The Last Challenge For Copernicanism?

    Directory of Open Access Journals (Sweden)

    Ćirković, M. M.

    2009-06-01

    Full Text Available We review Fermi's paradox (or the "Great Silence" problem, not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI, but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already more than three quarters of century old puzzle -- and a quarter of century since the last major review paper in the field by G. David Brin -- has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built in various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literatureon the subject. Finally, we consider the ramifications of variousclasses of hypotheses for the practical SETI projects. Somewhatparadoxically, it seems that the class of (neocatastrophichypotheses gives, on the balance, the strongest justification tooptimism regarding our current and near-future SETI efforts.

  9. 新特里芬悖论之VECM模型分析及对中国货币政策的启示%On the VECM Model Analysis of New Triffin Paradox and its Inspiration to Currency Policy in China

    Institute of Scientific and Technical Information of China (English)

    王雅炯

    2012-01-01

    In this paper,I propose the concept of New Triffin Paradox,and with cointegration test and VECM model,I set up a long-term equilibrium and short-term dynamic relationship among US dollar real effective exchange rate and currency supply and international capital revenue and expenditure.And by using impulse response function and variance decomposition principle,I make an analysis on the shock of variables' short-term fluctuation on US dollar real effective exchange rate.The effect of New Triffin Paradox problems on real economic activity is limit.When the world nations have a sustainable growing demand for US dollar,there does not exist a fundamental contradiction of international currency system led by US dollar,New Triffin Paradox can not be a theoretical basis for US dollar depreciation policy,and it provides reference for RMB internationalization and foreign exchange policy in a long time.%本文从特里芬悖论的原意出发提出新特里芬悖论概念,通过协整检验和构建向量误差修正模型(VECM),建立美元实际有效汇率与货币供应量、国际资本收支之间的长期均衡和短期动态关系,并利用脉冲响应函数和方差分解原理分析变量短期波动给美元实际有效汇率的冲击。新特里芬悖论产生的问题对实际经济活动影响有限,当世界各国的美元需求增长可持续时,以美元为主导的国际货币体系不存在根本性矛盾,新特里芬悖论并不能作为美元贬值政策的理论依据,这也对人民币国际化和外汇政策有长期的借鉴意义。

  10. Which factors could explain the low birth weight paradox?

    Directory of Open Access Journals (Sweden)

    Antônio Augusto Moura da Silva

    2006-08-01

    Full Text Available OBJECTIVE: Low birth weight children are unusual among well-off families. However, in Brazil, low birth weight rate was higher in a more developed city than in a less developed one. The study objective was to find out the reasons to explain this paradox. METHODS: A study was carried out in two municipalities, Ribeirão Preto (Southeastern Brazil and São Luís (Northeastern Brazil, which low birth weight rates were 10.7% and 7.6% respectively. Data from two birth cohorts were analyzed: 2,839 newborns in Ribeirão Preto in 1994 and 2,439 births in São Luís in 1997-1998. Multiple logistic regression analysis was performed, adjusted for confounders. RESULTS: Low birth weight risk factors in São Luís were primiparity, maternal smoking and maternal age less than 18 years. In Ribeirão Preto, the associated variables were family income between one and three minimum wages, maternal age less than 18 and equal to or more than 35 years, maternal smoking and cesarean section. In a combined model including both cohorts, Ribeirão Preto presented a 45% higher risk of low birth weight than São Luís. When adjusted for maternal smoking habit, the excess risk for low birth weight in Ribeirão Preto compared to São Luís was reduced by 49%, but the confidence interval was marginally significant. Differences in cesarean section rates between both cities contributed to partially explain the paradox. CONCLUSIONS: Maternal smoking was the most important risk factor for explaining the difference in low birth weight between both cities. The other factors contributed little to explain the difference in low birth weight rates.

  11. Paradoxical Roles of Antioxidant Enzymes: Basic Mechanisms and Health Implications.

    Science.gov (United States)

    Lei, Xin Gen; Zhu, Jian-Hong; Cheng, Wen-Hsing; Bao, Yongping; Ho, Ye-Shih; Reddi, Amit R; Holmgren, Arne; Arnér, Elias S J

    2016-01-01

    Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated from aerobic metabolism, as a result of accidental electron leakage as well as regulated enzymatic processes. Because ROS/RNS can induce oxidative injury and act in redox signaling, enzymes metabolizing them will inherently promote either health or disease, depending on the physiological context. It is thus misleading to consider conventionally called antioxidant enzymes to be largely, if not exclusively, health protective. Because such a notion is nonetheless common, we herein attempt to rationalize why this simplistic view should be avoided. First we give an updated summary of physiological phenotypes triggered in mouse models of overexpression or knockout of major antioxidant enzymes. Subsequently, we focus on a series of striking cases that demonstrate "paradoxical" outcomes, i.e., increased fitness upon deletion of antioxidant enzymes or disease triggered by their overexpression. We elaborate mechanisms by which these phenotypes are mediated via chemical, biological, and metabolic interactions of the antioxidant enzymes with their substrates, downstream events, and cellular context. Furthermore, we propose that novel treatments of antioxidant enzyme-related human diseases may be enabled by deliberate targeting of dual roles of the pertaining enzymes. We also discuss the potential of "antioxidant" nutrients and phytochemicals, via regulating the expression or function of antioxidant enzymes, in preventing, treating, or aggravating chronic diseases. We conclude that "paradoxical" roles of antioxidant enzymes in physiology, health, and disease derive from sophisticated molecular mechanisms of redox biology and metabolic homeostasis. Simply viewing antioxidant enzymes as always being beneficial is not only conceptually misleading but also clinically hazardous if such notions underpin medical treatment protocols based on modulation of redox pathways.

  12. From the BMI paradox to the obesity paradox: the obesity-mortality association in coronary heart disease.

    Science.gov (United States)

    Antonopoulos, A S; Oikonomou, E K; Antoniades, C; Tousoulis, D

    2016-10-01

    Despite a strong association between body weight and mortality in the general population, clinical evidence suggests better clinical outcome of overweight or obese individuals with established coronary heart disease. This finding has been termed the 'obesity paradox', but its existence remains a point of debate, because it is mostly observed when body mass index (BMI) is used to define obesity. Inherent limitations of BMI as an index of adiposity, as well as methodological biases and the presence of confounding factors, may account for the observed findings of clinical studies. In this review, our aim is to present the data that support the presence of a BMI paradox in coronary heart disease and then explore whether next to a BMI paradox a true obesity paradox exists as well. We conclude by attempting to link the obesity paradox notion to available translational research data supporting a 'healthy', protective adipose tissue phenotype. © 2016 World Obesity. © 2016 World Obesity.

  13. The Fermi Paradox, Self-Replicating Probes, and the Interstellar Transportation Bandwidth

    CERN Document Server

    Wiley, Keith B

    2011-01-01

    It has been widely acknowledged that self-replicating space-probes (SRPs) could explore the galaxy very quickly relative to the age of the galaxy. An obvious implication is that SRPs produced by extraterrestrial civilizations should have arrived in our solar system millions of years ago, and furthermore, that new probes from an ever-arising supply of civilizations ought to be arriving on a constant basis. The lack of observations of such probes underlies a frequently cited variation of the Fermi Paradox. We believe that a predilection for ETI-optimistic theories has deterred consideration of incompatible theories. Notably, SRPs have virtually disappeared from the literature. In this paper, we consider the most common arguments against SRPs and find those arguments lacking. By extension, we find recent models of galactic exploration which explicitly exclude SRPs to be unfairly handicapped and unlikely to represent natural scenarios. We also consider several other models that seek to explain the Fermi Paradox, ...

  14. The periodontal pain paradox: Difficulty on pain assesment in dental patients (The periodontal pain paradox hypothesis

    Directory of Open Access Journals (Sweden)

    Haryono Utomo

    2006-12-01

    Full Text Available In daily dental practice, the majority of patients’ main complaints are related to pain. Most patients assume that all pains inside the oral cavity originated from the tooth. One particular case is thermal sensitivity; sometimes patients were being able to point the site of pain, although there is neither visible caries nor secondary caries in dental radiograph. In this case, gingival recession and dentin hypersensitivity are first to be treated to eliminate the pain. If these treatments failed, pain may misdiagnose as pulpal inflammation and lead to unnecessary root canal treatment. Study in pain during periodontal instrumentation of plaque-related periodontitis revealed that the majority of patients feel pain and discomfort during probing and scaling. It seems obvious because an inflammation, either acute or chronic is related to a lowered pain threshold. However, in contrast, in this case report, patient suffered from chronic gingivitis and thermal sensitivity experienced a relative pain-free sensation during probing and scaling. Lowered pain threshold which accompanied by a blunted pain perception upon periodontal instrumentation is proposed to be termed as the periodontal pain paradox. The objective of this study is to reveal the possibility of certain factors in periodontal inflammation which may involved in the periodontal pain paradox hypothesis. Patient with thermal hypersensitivity who was conducted probing and scaling, after the relative pain-free instrumentation, thermal hypersensitivity rapidly disappeared. Based on the successful periodontal treatment, it is concluded that chronic gingivitis may modulate periodontal pain perception which termed as periodontal pain paradox

  15. ASA's Chandra Neon Discovery Solves Solar Paradox

    Science.gov (United States)

    2005-07-01

    NASA's Chandra X-ray Observatory survey of nearby sun-like stars suggests there is nearly three times more neon in the sun and local universe than previously believed. If true, this would solve a critical problem with understanding how the sun works. "We use the sun to test how well we understand stars and, to some extent, the rest of the universe," said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "But in order to understand the sun, we need to know exactly what it is made of," he added. It is not well known how much neon the sun contains. This is critical information for creating theoretical models of the sun. Neon atoms, along with carbon, oxygen and nitrogen, play an important role in how quickly energy flows from nuclear reactions in the sun's core to its edge, where it then radiates into space. Chandra X-ray Spectrum of II Pegasi Chandra X-ray Spectrum of II Pegasi The rate of this energy flow determines the location and size of a crucial stellar region called the convection zone. The zone extends from near the sun's surface inward approximately 125,000 miles. The zone is where the gas undergoes a rolling, convective motion much like the unstable air in a thunderstorm. "This turbulent gas has an extremely important job, because nearly all of the energy emitted at the surface of the sun is transported there by convection," Drake said. The accepted amount of neon in the sun has led to a paradox. The predicted location and size of the solar convection zone disagree with those deduced from solar oscillations. Solar oscillations is a technique astronomers previously relied on to probe the sun's interior. Several scientists have noted the problem could be fixed if the abundance of neon is in fact about three times larger than currently accepted. Attempts to measure the precise amount of neon in the Sun have been frustrated by a quirk of nature; neon atoms in the Sun give off no signatures in visible light. However, in a gas

  16. Non-thermal corrections to Hawking radiation versus the information paradox

    Energy Technology Data Exchange (ETDEWEB)

    Dvali, Gia [Arnold Sommerfeld Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen (Germany); Max-Planck-Institut fuer Physik, Muenchen (Germany); Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY (United States)

    2016-01-15

    We provide a model-independent argument indicating that for a black hole of entropy N the non-thermal deviations from Hawking radiation, per each emission time, are of order 1/N, as opposed to e{sup -N}. This fact abolishes the standard a priory basis for the information paradox. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Geology and total petroleum systems of the Paradox Basin, Utah, Colorado, New Mexico, and Arizona

    Science.gov (United States)

    Whidden, Katherine J.; Lillis, Paul G.; Anna, Lawrence O.; Pearson, Krystal M.; Dubiel, Russell F.

    2014-01-01

    The geological model for the development of the Total Petroleum Systems (TPSs) within the Paradox Basin formed the foundation of the recent U.S. Geological Survey assessment of undiscovered, technically recoverable resources in the basin. Five TPSs were defined, of which three have known production and two are hypothetical. These TPSs are based on geologic elements of the basin and the potential development of Precambrian, Devonian, Pennsylvanian, Permian-Mississippian, and Cretaceous source rock intervals.

  18. Aging and communication in the twin paradox

    Science.gov (United States)

    de Wolf, David A.

    2016-11-01

    The twin paradox of the special theory of relativity has given rize to a large body of literature discussing its implications. In its standard form, the traveler changes velocity only at the destination of the trip, so that he appears to perceive an improbably instantaneous and non-continuous change in age of the stationary twin. In this work, a smooth velocity/acceleration profile is used that allows the abrupt velocity-change case as a limit. All gravitational effects are ignored in this treatment. Aside from mutual perception of simultaneous clock times in an accelerating frame, constant communication of clock times between the twins by means of (digital) light signals is shown to be possible, in principle if not in practice.

  19. Cannabinoid Hyperemesis Syndrome: A Paradoxical Cannabis Effect

    Directory of Open Access Journals (Sweden)

    Ivonne Marie Figueroa-Rivera

    2015-01-01

    Full Text Available Despite well-established antiemetic properties of marijuana, there has been increasing evidence of a paradoxical effect in the gastrointestinal tract and central nervous system, given rise to a new and underrecognized clinical entity called the Cannabinoid Hyperemesis Syndrome. Reported cases in the medical literature have established a series of patients exhibiting a classical triad of symptoms: cyclic vomiting, chronic marijuana use, and compulsive bathing. We present a case of a 29-year-old man whose clinical presentation strongly correlates with cannabinoid hyperemesis syndrome. Despite a diagnosis of exclusion, this syndrome should be considered plausible in the setting of a patient with recurrent intractable vomiting and a strong history of cannabis use as presented in this case.

  20. Quantum Solution to the Extended Newcomb's Paradox

    CERN Document Server

    Chi, D P; Chi, Dong Pyo; Jeong, Kabgyun

    2005-01-01

    We regard the Newcomb's Paradox as a reduction of the Prisoner's Dilemma and search for the considerable quantum solution. The all known classical solutions to the Newcomb's problem always imply that human has freewill and is due to the unfair set-up(including strategies)of the Newcomb's Problem. In this reason, we here substitute the asymmetric payoff matrix to the general form of the payoff matrix M and consider both of them use the same quantum strategy. As a result we obtained the fair Nash equilibrium, which is better than the case using classical strategies. This means that whether the supernatural being has the precognition or not depends only on the choice of strategy.

  1. Weakly isolated horizon information loss paradox

    CERN Document Server

    Chen, Ge-Rui

    2014-01-01

    In this paper we investigate the information loss paradox of weakly isolated horizon(WIH) based on the Parikh and Wilczek's tunneling spectrum. We find that there are correlations among Hawking radiations from weakly isolated horizon, the information can be carried out in terms of correlations between sequential emissions, and the radiation is an entropy conservation process. We generalize Refs.[11-13]' results to a more general spacetime. Through revisiting the calculation of tunneling of weakly isolated horizon, we find that Ref.[12]'s requirement that radiating particles have the same angular momenta of unit mass as that of black hole is not needed, and the energy and angular momenta of emitting particles are very arbitrary, which should be restricted only by keeping the cosmic censorship of black hole.

  2. Dynamics in Braess Paradox with Nonimpulsive Commuters

    Directory of Open Access Journals (Sweden)

    Arianna Dal Forno

    2015-01-01

    the individual rationality leads to collective irrationality. In the literature, the dynamics has been analyzed when considering impulsive commuters, i.e., those who switch choice regardless of the actual difference between costs. We analyze a dynamical version of the paradox with nonimpulsive commuters, who change road proportionally to the cost difference. When only two roads are available, we provide a rigorous proof of the existence of a unique fixed point showing that it is globally attracting even if locally unstable. When a new road is added the system becomes discontinuous and two-dimensional. We prove that still a unique fixed point exists, and its global attractivity is numerically evidenced, also when the fixed point is locally unstable. Our analysis adds a new insight in the understanding of dynamics in social dilemma.

  3. The St. Petersburg paradox: An experimental solution

    Science.gov (United States)

    Da Silva, Sergio; Matsushita, Raul

    2016-03-01

    The St. Petersburg paradox refers to a gamble of infinite expected value, where people are likely to spend only a small entrance fee for it. There is a huge volume of literature that mostly concentrates on the psychophysics of the game; experiments are scant. Here, rather than focusing on the psychophysics, we offer an experimental, "physical" solution as if robots played the game. After examining the time series formed by one billion plays, we: confirm that there is no characteristic scale for this game; explicitly formulate the implied power law; and identify the type of α-stable distribution associated with the game. We find an α = 1 and, thus, the underlying distribution of the game is a Cauchy flight, as hinted by Paul Samuelson.

  4. Aging and communication in the twin paradox

    CERN Document Server

    de Wolf, David A

    2016-01-01

    The twin paradox of the special theory of relativity has given rise to a large body of literature discussing its implications. In its standard form, the traveler changes velocity only at the destination of the trip, so that he appears to perceive an improbably instantaneous and non-continuous change in age of the stationary twin. In this work, a smooth velocity/acceleration profile is used that allows the abrupt velocity-change case as a limit. All gravitational effects are ignored in this treatment. Aside from mutual perception of simultaneous clock times in an accelerating frame, constant communication of clock times between the twins by means of (digital) light signals is shown to be possible, in principle if not in practice.

  5. The paradox of evil/homosexuality.

    Science.gov (United States)

    Woo, Juhyun

    2015-01-01

    In this article, I analyze "personal experience stories around the homosexual" that entered into the parliamentary debates on the Sexual Offences Act in Britain in the 1950s and 1960s and shaped understandings of sexual citizenship in particular ways. Specific attention is paid to the effects of political storytelling involved in the making of British sexual citizens. I explore how the paradoxical figure of the evil homosexual emerges and how politicians, in telling stories of the evil homosexuality, police the border that can effectively separate sexual outsiders from sexual citizens. I conclude with an analysis of these stories, and how their telling is closely linked to the postwar social welfare thinking in Britain.

  6. Paradoxes and Opportunities in Logistic Outsourcing Research

    Directory of Open Access Journals (Sweden)

    Đurđica Stojanović

    2012-11-01

    Full Text Available Historically, very few logistic trends have caught the attention of academics and practitioners to the same extent as outsourcing. A comprehensive literature review reveals two reasons for this continual topicality. The problem complexity and the business environment dynamics – including an interaction with other main trends in logistics and modern supply chains – both led to a permanent literature gap, indicating the need to explore some new aspects of logistics outsourcing (LO. In this paper, a new LO research perspective has been explored by identifying some weaknesses in the main LO research streams and related common viewpoints which led to six ‘logistics outsourcing research paradoxes’. Each of these paradoxes is briefly described and their links with research streams and common views on LO discussed. Finally, the nature of some known opportunities for further research is better explained and some overlooked research opportunities are highlighted.

  7. Statins and the cholesterol mortality paradox.

    Science.gov (United States)

    Nunes, José Pedro L

    2017-02-01

    Large-scale randomised controlled trials, carried out in the context of secondary cardiovascular prevention, have shown that statins are superior to placebo: these drugs were shown to decrease cardiovascular events and total mortality. A further set of clinical trials compared high intensity to low/standard intensity LDL cholesterol lowering in the same setting (using either statins or a statin/ezetimibe association). In this case, a decrease in LDL cholesterol and a concomitant significant reduction in cardiovascular events were seen with intensive therapy, however with no change in total mortality. This phenomenon we may term the LDL cholesterol mortality paradox. It could be due either to the prevention (by high-intensity therapy) of episodes not severe enough to lead to the death of patients, or to high-intensity therapy leading to the death of some patients at the same time as preventing the death of others, with a null aggregate effect. Several types of adverse effects have been seen with statin therapy, such as a possible increased incidence of Diabetes mellitus and of myopathy. The decision to start high-intensity LDL cholesterol lowering (rather than low- or moderate-intensity statin treatment) should be evaluated on a case-by-case basis, taking into consideration the overall aspects of each patient, including the patient's preferences. High-intensity LDL cholesterol lowering, up to the present moment, has failed to produce a change in overall prognosis (total mortality), and should not therefore be mandatory in secondary cardiovascular prevention. It remains to be seen if a similar LDL cholesterol mortality paradox occurs with new drugs targeting plasma lipids.

  8. The Epigenetic Paradox of Pluripotent ES Cells.

    Science.gov (United States)

    Festuccia, Nicola; Gonzalez, Inma; Navarro, Pablo

    2017-05-19

    The propagation and maintenance of gene expression programs are at the foundation of the preservation of cell identity. A large and complex set of epigenetic mechanisms enables the long-term stability and inheritance of transcription states. A key property of authentic epigenetic regulation is being independent from the instructive signals used for its establishment. This makes epigenetic regulation, particularly epigenetic silencing, extremely robust and powerful to lock regulatory states and stabilise cell identity. In line with this, the establishment of epigenetic silencing during development restricts cell potency and maintains the cell fate choices made by transcription factors (TFs). However, how more immature cells that have not yet established their definitive fate maintain their transitory identity without compromising their responsiveness to signalling cues remains unclear. A paradigmatic example is provided by pluripotent embryonic stem (ES) cells derived from a transient population of cells of the blastocyst. Here, we argue that ES cells represent an interesting "epigenetic paradox": even though they are captured in a self-renewing state characterised by extremely efficient maintenance of their identity, which is a typical manifestation of robust epigenetic regulation, they seem not to heavily rely on classical epigenetic mechanisms. Indeed, self-renewal strictly depends on the TFs that previously instructed their undifferentiated identity and relies on a particular signalling-dependent chromatin state where repressive chromatin marks play minor roles. Although this "epigenetic paradox" may underlie their exquisite responsiveness to developmental cues, it suggests that alternative mechanisms to faithfully propagate gene regulatory states might be prevalent in ES cells. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. The paradoxes of the consumer society

    Directory of Open Access Journals (Sweden)

    A. N. Il’In

    2016-01-01

    Full Text Available The article describes two characteristic of the consumer society of the paradox. The first is expressed in the contradiction between the desire for himself by exposure to high consumer standards and constraints of a financial nature. Specifics of consumer culture requires to make demonstrative waste of money, even if it is associated with financial resources. Demonstrative waste of money exercise by savings on invisible to others spheres of life, as “message” on the status becomes more important need than the satisfaction of these needs. The relationship between income and consumption does not seem unambiguous. Updated trend of the sense of consumption goods, pseudoconsumerism, realizing the need to seem - one of fictitious needs, which in practice translates into implementation of strategy is symbolic of deception. There is a “fictitious second order”, which is not associated with the symbolic meaning of a certain good, and with the symbolic meaning of goods, which is not cash, but is missing. Consumption has shifted imitating under the consumption of performance, consumption of simulacrum and virtuality. The dichotomy of “to have or to be” in this case is replaced by the dichotomy of “to have or to pass” and, in turn, “to pass or to be”. The second paradox is expressed in cultivating the desire to emphasize with consumption individuality that goes away when the practice becomes mass. Standardization is carried out under the rhetoric about elitism. The samples on offer as elitist, their attractiveness ascribe to itself the masses. It’s elitist by material unavailable to most people, but the mass by the desire of many people to be attached to them. Characteristic of a consumer society fashion consciously orients a select minority, but the underlying basis remains unconscious orientation to universality. Fashion stimulating consumption standards and to the implementation of individual choice, which constrained by these

  10. Obesity Paradox should not interfere with public health efforts.

    Science.gov (United States)

    Stevens, J; Bradshaw, P T; Truesdale, K P; Jensen, M D

    2015-01-01

    The Obesity Paradox could result in confusing messages that derail beneficial environmental changes and lead to reduced efforts by physicians to provide healthy lifestyle treatment plans to their obese patients. The Obesity Paradox applies in the main to individuals who have a disease, and therefore observed associations with mortality illustrating the Paradox may be more susceptible to certain types of bias than would be found in healthy individuals. Although individualization of weight loss advice for patients with serious disease is appropriate in medical settings, this does not supplant the need for general efforts to prevent and treat obesity.

  11. A Quantum Rosetta Stone for the Information Paradox

    CERN Document Server

    Zayas, Leopoldo A Pando

    2014-01-01

    The black hole information loss paradox epitomizes the contradictions between general relativity and quantum field theory. The AdS/CFT correspondence provides an implicit answer for the information loss paradox in black hole physics by equating a gravity theory with an explicitly unitary field theory. Gravitational collapse in asymptotically AdS spacetimes is generically turbulent. Given that the mechanism to read out the information about correlations functions in the field theory side is plagued by deterministic classical chaos, we argue that quantum chaos might provide the true Rosetta Stone for answering the information paradox in the context of the AdS/CFT correspondence.

  12. A quantum Rosetta Stone for the information paradox

    Science.gov (United States)

    Pando Zayas, Leopoldo A.

    2014-11-01

    The black hole information loss paradox epitomizes the contradictions between general relativity and quantum field theory. The AdS/conformal field theory (CFT) correspondence provides an implicit answer for the information loss paradox in black hole physics by equating a gravity theory with an explicitly unitary field theory. Gravitational collapse in asymptotically AdS spacetimes is generically turbulent. Given that the mechanism to read out the information about correlations functions in the field theory side is plagued by deterministic classical chaos, we argue that quantum chaos might provide the true Rosetta Stone for answering the information paradox in the context of the AdS/CFT correspondence.

  13. No information or horizon paradoxes for Th. Smiths

    CERN Document Server

    Maes, Christian

    2015-01-01

    'Th'e 'S'tatistical 'm'echanician 'i'n 'th'e 's'treet (our Th. Smiths) must be surprised upon hearing popular versions of some of today's most discussed paradoxes in astronomy and cosmology. In fact, rather standard reminders of the meaning of thermal probabilities in statistical mechanics appear to answer the horizon problem (one of the major motivations for inflation theory) and the information paradox (related to black hole physics), at least as they are usually presented. Still the paradoxes point to interesting gaps in our statistical understanding of (quantum) gravitational effects.

  14. A simple explanation of the classic hydrostatic paradox

    Science.gov (United States)

    Kontomaris, Stylianos-Vasileios; Malamou, Anna

    2016-07-01

    An interesting problem in fluid mechanics, with significant educational importance, is the classic hydrostatic paradox. The hydrostatic paradox states the fact that in different shaped containers, with the same base area, which are filled with a liquid of the same height, the applied force by the liquid on the base of each container is exactly the same. However, if the shape of the container is different, the amount of the liquid (and as a consequence the weight) can greatly vary. In this paper, a simple explanation of the hydrostatic paradox, specifically designed and implemented for educational purposes regarding secondary education, is provided.

  15. Reversal of a Suspected Paradoxical Reaction to Zopiclone with Flumazenil

    Directory of Open Access Journals (Sweden)

    Zarah Jordahn

    2016-01-01

    Full Text Available We describe the care for an elderly woman who was admitted to the intensive care unit (ICU to receive noninvasive ventilation for acute exacerbation of chronic obstructive pulmonary disease. After administration of the sleeping pill zopiclone, a nonbenzodiazepine receptor agonist (NBRA, the patient became agitated and was confused, a possible paradoxical reaction to benzodiazepines. These symptoms were immediately resolved after treatment with flumazenil, usually used to reverse the adverse effects of benzodiazepines or NBRAs and to reverse paradoxical reactions to benzodiazepines. This case indicates that zopiclone induced behavioral changes resembling a paradoxical reaction to benzodiazepines and these symptoms may be treated with flumazenil.

  16. Natural resistance to cancers: a Darwinian hypothesis to explain Peto’s paradox

    Directory of Open Access Journals (Sweden)

    Roche Benjamin

    2012-09-01

    Full Text Available Abstract Background Peto's paradox stipulates that there is no association between body mass (a surrogate of number of cells and longevity and cancer prevalence in wildlife species. Resolving this paradox is a very promising research direction to understand mechanisms of cancer resistance. As of present, research has been focused on the consequences of these evolutionary pressures rather than of their causes. Discussion Here, we argue that evolution through natural selection may have shaped mechanisms of cancer resistance in wildlife species and that this can result in a threshold in body mass above which oncogenic and tumor suppressive mechanisms should be increasingly purified and positively selected, respectively. Summary We conclude that assessing wildlife species in their natural ecosystems, especially through theoretical modeling, is the most promising way to understand how evolutionary processes can favor one or the other pathway. This will provide important insights into mechanisms of cancer resistance.

  17. Dynamics of mechanical systems with multiple sliding contacts: new faces of Painlev\\'e's paradox

    CERN Document Server

    Várkonyi, Péter L

    2016-01-01

    We investigate the dynamics of finite degree-of-freedom, planar mechanical systems with multiple sliding, unilateral frictional point contacts. A complete classification of systems with 2 sliding contacts is given. The contact-mode based approach of rigid body mechanics is combined with linear stability analysis using a compliant contact model to determine the feasibility and the stability of every possible contact mode in each class. Special forms of non-stationary contact dynamics including "impact without collision" and "reverse chattering" are also investigated. Many types of solution inconsistency and the indeterminacy are identified and new phenomena related to Painlev\\'e"s non-existence and non-uniqueness paradoxes are discovered. Among others, we show that the non-existence paradox is not fully resolvable by considering impulsive contact forces. These results contribute to a growing body of evidence that rigid body mechanics cannot be developed into a complete and self-consistent theory in the presenc...

  18. A resource-based game theoretical approach for the paradox of the plankton.

    Science.gov (United States)

    Huang, Weini; de Araujo Campos, Paulo Roberto; Moraes de Oliveira, Viviane; Fagundes Ferrreira, Fernando

    2016-01-01

    The maintenance of species diversity is a central focus in ecology. It is not rare to observe more species than the number of limiting resources, especially in plankton communities. However, such high species diversity is hard to achieve in theory under the competitive exclusion principles, known as the plankton paradox. Previous studies often focus on the coexistence of predefined species and ignore the fact that species can evolve. We model multi-resource competitions using evolutionary games, where the number of species fluctuates under extinction and the appearance of new species. The interspecific and intraspecific competitions are captured by a dynamical payoff matrix, which has a size of the number of species. The competition strength (payoff entries) is obtained from comparing the capability of species in consuming resources, which can change over time. This allows for the robust coexistence of a large number of species, providing a possible solution to the plankton paradox.

  19. Boxfish swimming paradox resolved: forces by the flow of water around the body promote manoeuvrability.

    Science.gov (United States)

    Van Wassenbergh, S; van Manen, K; Marcroft, T A; Alfaro, M E; Stamhuis, E J

    2015-02-06

    The shape of the carapace protecting the body of boxfishes has been attributed an important hydrodynamic role in drag reduction and in providing automatic, flow-direction realignment and is therefore used in bioinspired design of cars. However, tight swimming-course stabilization is paradoxical given the frequent, high-performance manoeuvring that boxfishes display in their spatially complex, coral reef territories. Here, by performing flow-tank measurements of hydrodynamic drag and yaw moments together with computational fluid dynamics simulations, we reverse several assumptions about the hydrodynamic role of the boxfish carapace. Firstly, despite serving as a model system in aerodynamic design, drag-reduction performance was relatively low compared with more generalized fish morphologies. Secondly, the current theory of course stabilization owing to flow over the boxfish carapace was rejected, as destabilizing moments were found consistently. This solves the boxfish swimming paradox: destabilizing moments enhance manoeuvrability, which is in accordance with the ecological demands for efficient turning and tilting.

  20. How predator functional responses and Allee effects in prey affect the paradox of enrichment and population collapses

    NARCIS (Netherlands)

    Boukal, D.; Sabelis, M.W.; Berec, L.

    2007-01-01

    In Rosenzweig-MacArthur models of predator-prey dynamics, Allee effects in prey usually destabilize interior equilibria and can suppress or enhance limit cycles typical of the paradox of enrichment. We re-evaluate these conclusions through a complete classification of a wide range of Allee effects

  1. Tests of Branch Splitting and Branch-Splitting Independence in Allais Paradoxes with Positive and Mixed Consequences

    Science.gov (United States)

    Birnbaum, Michael H.

    2007-01-01

    Four experiments with 1391 participants compared descriptive models of risky decision making. The first replicated and extended evidence refuting cumulative prospect theory (CPT) as an explanation of Allais paradoxes. The second and third experiments used a new design to unconfound tests of upper and lower coalescing, which allows tests of…

  2. Intimate partner violence against women and the Nordic paradox.

    Science.gov (United States)

    Gracia, Enrique; Merlo, Juan

    2016-05-01

    Nordic countries are the most gender equal countries in the world, but at the same time they have disproportionally high prevalence rates of intimate partner violence (IPV) against women. High prevalence of IPV against women, and high levels of gender equality would appear contradictory, but these apparently opposite statements appear to be true in Nordic countries, producing what could be called the 'Nordic paradox'. Despite this paradox being one of the most puzzling issues in the field, this is a research question rarely asked, and one that remains unanswered. This paper explores a number of theoretical and methodological issues that may help to understand this paradox. Efforts to understand the Nordic paradox may provide an avenue to guide new research on IPV and to respond to this major public health problem in a more effective way.

  3. THE PARADOX OF THE PLANKTON: COMMUNITY STRUCTURE PROMOTES BLOOMS

    Science.gov (United States)

    ABSTRACT: The 'paradox of the plankton' refers to commensalism as well as symbiosis, predation, and impacts of non equilibrium conditions between two planktoniccompetitors. In regards to commensalism, phytoplankton can release organic carbon that enhances growth of its ba...

  4. Contribution of cardiorespiratory fitness to the obesity paradox.

    Science.gov (United States)

    McAuley, Paul A; Beavers, Kristen M

    2014-01-01

    Until recently, cardiorespiratory fitness (CRF) has been overlooked as a potential modifier of the inverse association between obesity and mortality (the so-called obesity paradox), observed in patients with known or suspected cardiovascular (CV) disease. Evidence from five observational cohort studies of 30,104 patients (87% male) with CV disease indicates that CRF significantly alters the obesity paradox. There is general agreement across studies that the obesity paradox persists among patients with low CRF, regardless of whether adiposity is assessed by body mass index, waist circumference, or percentage body fat. However, among patients with high CRF, risk of all-cause mortality is lowest for the overweight category in some, but not all, studies, suggesting that higher levels of fitness may modify the relationship between body fatness and survival in patients manifesting an obesity paradox. Further study is needed to better characterize the joint contribution of CRF and obesity on mortality in diverse populations. © 2014.

  5. A retrodiction paradox in quantum and classical optics

    CERN Document Server

    Aiello, Andrea

    2015-01-01

    Quantum mechanics represents one of the greatest triumphs of human intellect and, undoubtedly, is the most successful physical theory we have to date. However, since its foundation about a century ago, it has been uninterruptedly the center of harsh debates ignited by the counterintuitive character of some of its predictions. The subject of one of these heated discussions is the so-called "retrodiction paradox", namely a deceptive inconsistency of quantum mechanics which is often associated with the "measurement paradox" and the "collapse of the wave function"; it comes from the apparent time-asymmetry between state preparation and measurement. Actually, in the literature one finds several versions of the retrodiction paradox; however, a particularly insightful one was presented by Sir Roger Penrose in his seminal book \\emph{The Road to Reality}. Here, we address the question to what degree Penrose's retrodiction paradox occurs in the classical and quantum domain. We achieve a twofold result. First, we show t...

  6. Obesity and the obesity paradox in heart failure.

    Science.gov (United States)

    Gupta, Pritha P; Fonarow, Gregg C; Horwich, Tamara B

    2015-02-01

    Obesity has reached epidemic proportions in the general population and is associated with an increased risk for the development of new-onset heart failure (HF). However, in acute and chronic HF, overweight and mild to moderate obesity is associated with substantially improved survival compared with normal weight. This phenomenon has been termed the "obesity paradox" in HF. The majority of data pertaining to the obesity paradox identifies obesity with body mass index; however, the reliability of this method has been questioned. Newer studies have explored the use of other measures of body fat and body composition, including waist circumference, waist-to-hip ratio, skinfold thickness, and bioelectrical impedance analysis of body composition. The relationship between the obesity paradox and cardiorespiratory fitness in HF is also discussed in this review, and we explore the various potential explanations for the obesity paradox and summarize the current evidence and guidelines for intentional weight loss treatments for HF in the obese population.

  7. Notes on the firewall paradox, complexity, and quantum theory

    CERN Document Server

    Schlesinger, Karl-Georg

    2014-01-01

    We investigate what it means to apply the solution, proposed to the firewall paradox by Harlow and Hayden, to the famous quantum paradoxes of Sch\\"odinger's Cat and Wigner's Friend if ones views these as posing a thermodynamic decoding problem (as does Hawking radiation in the firewall paradox). The implications might point to a relevance of the firewall paradox for the axiomatic and set theoretic foundations underlying mathematics. We reconsider in this context the results of Benioff on the foundational challenges posed by the randomness postulate of quantum theory. A central point in our discussion is that one can mathematically not naturally distinguish between computational complexity (as central to the approach of Harlow and Hayden and further developed by Susskind) and proof theoretic complexity (since they represent the same concept on a Turing machine), with the latter being related to a finite bound on Kolmogorov entropy (due to Chaitin incompleteness).

  8. Maximization Paradox: Result of Believing in an Objective Best.

    Science.gov (United States)

    Luan, Mo; Li, Hong

    2017-05-01

    The results from four studies provide reliable evidence of how beliefs in an objective best influence the decision process and subjective feelings. A belief in an objective best serves as the fundamental mechanism connecting the concept of maximizing and the maximization paradox (i.e., expending great effort but feeling bad when making decisions, Study 1), and randomly chosen decision makers operate similar to maximizers once they are manipulated to believe that the best is objective (Studies 2A, 2B, and 3). In addition, the effect of a belief in an objective best on the maximization paradox is moderated by the presence of a dominant option (Study 3). The findings of this research contribute to the maximization literature by demonstrating that believing in an objective best leads to the maximization paradox. The maximization paradox is indeed the result of believing in an objective best.

  9. Solution of Supplee's submarine paradox through special and general relativity

    Science.gov (United States)

    Vieira, R. S.

    2016-12-01

    In 1989 Supplee described an apparent relativistic paradox on which a submarine seems to sink to observers at rest within the ocean, but it rather seems to float in the submarine proper frame. In this letter, we show that the paradox arises from a misuse of the Archimedes principle in the relativistic case. Considering first the special relativity, we show that any relativistic force field can be written in the Lorentz form, so that it can always be decomposed into a static (electric-like) and a dynamic (magnetic-like) part. These gravitomagnetic effects provide a relativistic formulation of Archimedes principle, from which the paradox is explained. Besides, if the curved spacetime on the vicinity of the Earth is taken into account, we show that the gravitational force exerted by the Earth on a moving body must increase with the speed of the body. The submarine paradox is then analyzed again with this speed-dependent gravitational force.

  10. Zeno Paradox for Bohmian Trajectories: The Unfolding of the Metatron

    CERN Document Server

    de Gosson, Maurice

    2010-01-01

    We study an analogue of the quantum Zeno paradox for the Bohm trajectory of a sharply located particle (or a system of particles). We show that a continuously observed Bohm trajectory is the classical trajectory predicted by Hamiltonian mechanics.

  11. THE PARADOX OF THE PLANKTON: COMMUNITY STRUCTURE PROMOTES BLOOMS

    Science.gov (United States)

    ABSTRACT: The 'paradox of the plankton' refers to commensalism as well as symbiosis, predation, and impacts of non equilibrium conditions between two planktoniccompetitors. In regards to commensalism, phytoplankton can release organic carbon that enhances growth of its ba...

  12. Exploring a Parabolic Paradox with the Graphing Calculator.

    Science.gov (United States)

    Shilgalis, Tom

    1997-01-01

    Argues that technology influences mathematics education by enabling students and teachers to discover and demonstrate generalizations and properties that were unthinkable a few years ago. Focuses on one example related to a paradox involving parabolas. (DDR)

  13. Ending the myth of the St Petersburg Paradox

    Directory of Open Access Journals (Sweden)

    Robert Vivian

    2013-09-01

    Full Text Available Nicolas Bernoulli suggested the St Petersburg game, nearly 300 years ago, which is widely believed to produce a paradox in decision theory.  This belief stems from a long standing mathematical error in the original calculation of the expected value of the game.   This article argues that, in addition to the mathematical error, there are also methodological considerations which gave rise to the paradox.   This article explains these considerations and why because of the modern computer, the same considerations, when correctly applied, also demonstrate that no paradox exists.  Because of the longstanding belief that a paradox exists it is unlikely the mere mathematical correction will end the myth.  The article explains why it is the methodological correction which will dispel the myth.

  14. Exploring a Parabolic Paradox with the Graphing Calculator.

    Science.gov (United States)

    Shilgalis, Tom

    1997-01-01

    Argues that technology influences mathematics education by enabling students and teachers to discover and demonstrate generalizations and properties that were unthinkable a few years ago. Focuses on one example related to a paradox involving parabolas. (DDR)

  15. One-Piece Faraday Generator: A Paradoxical Experiment from 1851

    Science.gov (United States)

    Crooks, M. J.; And Others

    1978-01-01

    Describes an experiment based on Faraday's one-piece generator, where the rotating disk is replaced by a cylindrical permanent magnet. Explains the apparent paradox that an observer in an inertial frame could measure his absolute velocity. (GA)

  16. Paradoxical proepileptic response to NMDA receptor blockade linked to cortical interneuron defect in stargazer mice

    Directory of Open Access Journals (Sweden)

    Atul eMaheshwari

    2013-09-01

    Full Text Available Paradoxical seizure exacerbation by antiepileptic medication is a well-known clinical phenomenon in epilepsy, but the cellular mechanisms remain unclear. One possibility is enhanced network disinhibition by unintended suppression of inhibitory interneurons. We investigated this hypothesis in the stargazer mouse model of absence epilepsy, which bears a mutation in stargazin, an AMPA receptor trafficking protein. If AMPA signaling onto inhibitory GABAergic neurons is impaired, their activation by glutamate depends critically upon NMDA receptors. Indeed, we find that stargazer seizures are exacerbated by NMDA receptor blockade with CPP and MK-801, whereas other genetic absence epilepsy models are sensitive to these antagonists. To determine how an AMPA receptor trafficking defect could lead to paradoxical network activation, we analyzed stargazin and AMPA receptor localization and found that stargazin is detected exclusively in parvalbumin-positive (PV+ fast-spiking interneurons in somatosensory cortex, where it is co-expressed with the AMPA receptor subunit GluA4. PV+ cortical interneurons in stargazer show a near two-fold decrease in the dendrite:soma GluA4 expression ratio compared to wild type littermates. We explored the functional consequence of this trafficking defect on network excitability in neocortical slices. Both NMDA receptor antagonists suppressed 0 Mg2+ induced network discharges in wild type but augmented bursting in stargazer cortex. Interneurons mediate this paradoxical response, since the difference between genotypes was masked by GABA receptor blockade. Our findings provide a cellular locus for AMPA receptor-dependent signaling defects in stargazer cortex and define an interneuron-dependent mechanism for paradoxical seizure exacerbation in absence epilepsy.

  17. Estimation of salt loads for the Dolores River in the Paradox Valley, Colorado, 1980–2015

    Science.gov (United States)

    Mast, M. Alisa

    2017-07-13

    Regression models that relate total dissolved solids (TDS) concentrations to specific conductance were used to estimate salt loads for two sites on the Dolores River in the Paradox Valley in western Colorado. The salt-load estimates will be used by the Bureau of Reclamation to evaluate salt loading to the river coming from the Paradox Valley and the effect of the Paradox Valley Unit (PVU), a project designed to reduce the salinity of the Colorado River. A second-order polynomial provided the best fit of the discrete data for both sites on the river. The largest bias occurred in samples with elevated sulfate concentrations (greater than 500 milligrams per liter), which were associated with short-duration runoff events in late summer and fall. Comparison of regression models from a period of time before operation began at the PVU and three periods after operation began suggests the relation between TDS and specific conductance has not changed over time. Net salt gain through the Paradox Valley was estimated as the TDS load at the downstream site minus the load at the upstream site. The mean annual salt gain was 137,900 tons per year prior to operation of the PVU (1980–1993) and 43,300 tons per year after the PVU began operation (1997–2015). The difference in annual salt gain in the river between the pre-PVU and post-PVU periods was 94,600 tons per year, which represents a nearly 70 percent reduction in salt loading to the river.

  18. Obesity Paradox in End-Stage Kidney Disease Patients

    OpenAIRE

    Park, Jongha; Ahmadi, Seyed-Foad; Streja, Elani; Molnar, Miklos Z; Flegal, Katherine M.; Gillen, Daniel; Kovesdy, Csaba P.; Kalantar-Zadeh, Kamyar

    2013-01-01

    In the general population, obesity is associated with increased cardiovascular risk and decreased survival. In patients with end-stage renal disease (ESRD), however, an “obesity paradox” or “reverse epidemiology” (to include lipid and hypertension paradoxes) has been consistently reported, i.e. a higher body mass index (BMI) is paradoxically associated with better survival. This survival advantage of large body size is relatively consistent for hemodialysis patients across racial and regional...

  19. Editor, executive and entrepreneur: strategic paradoxes in the digital age

    OpenAIRE

    2016-01-01

    To survive in today’s increasingly complex business environments, firms must embrace strategic paradoxes: contradictory yet interrelated objectives that persist over time. This can be one of toughest of all leadership challenges, as managers must accept inconsistency and contradictions. In this article, we develop and empirically test a set of hypotheses related to ambidexterity, a key example of a paradoxical strategy. Through our analysis of data from a survey of executive le...

  20. Governance and Developing Asia: Concepts, Measurements, Determinants, and Paradoxes

    OpenAIRE

    M. G. Quibria

    2014-01-01

    Recent years have seen the emergence of a considerable volume of literature on governance and its role in economic and social development of a country. This paper provides a critical review of the literature. This review brings into the open a number of serious conceptual, measurement, and data issues as well as the existence of an Asian governance paradox - i.e., a general disjunction between growth and governance in most Asian economies. This paradox seems to suggest that much of the curren...

  1. Brownian motion and gambling: from ratchets to paradoxical games

    CERN Document Server

    Parrondo, J M R

    2014-01-01

    Two losing gambling games, when alternated in a periodic or random fashion, can produce a winning game. This paradox has been inspired by certain physical systems capable of rectifying fluctuations: the so-called Brownian ratchets. In this paper we review this paradox, from Brownian ratchets to the most recent studies on collective games, providing some intuitive explanations of the unexpected phenomena that we will find along the way.

  2. Consumer response: the paradoxes of food and health.

    Science.gov (United States)

    Biltekoff, Charlotte

    2010-03-01

    The papers in the session "Food Culture and Consumer Response," show how important people's values, beliefs, aspirations and social context are to their dietary health. They also reveal several tensions that shape consumer responses to healthy food. This essay discusses the paradoxical nature of eating habits in general, and describes three paradoxes related specifically to the challenges of providing food for health in the 21st century: pleasure/health, technology/nature, innovation/nostalgia.

  3. Paradoxical Cerebral Fat Embolism in Revision Hip Surgery

    Directory of Open Access Journals (Sweden)

    Nicolás S. Piuzzi

    2014-01-01

    Full Text Available The incidence of clinical fat embolism syndrome (FES is low (<1% whilst fat embolism (FE of marrow fat appears to occur more often (Mellor and Soni (2001. Paradoxical brain FE may occur in patients undergoing hip orthopedic surgery who have an undocumented patent foramen ovale (PFO. We report a case of an eighty-year-old male patient, who underwent a scheduled revision hip surgery suffering a paradoxical cerebral FE.

  4. Addressing the Old Water Paradox using tritium

    Science.gov (United States)

    Cartwright, Ian; Morgenstern, Uwe

    2017-04-01

    The paradox that much of the water that contributes to streams during high flow events appears to be derived from relatively old stores in catchments has been of interest to hydrogeologists for several decades. It is a common observation that stream chemistry varies less than would be expected if simple dilution of groundwater inflows by event water occurred during storm events. However, it is not clear to what extent this observation reflects displacement of water from the soils or the regolith vs. enhanced discharge of older groundwater into the stream. Here we use tritium in conjunction with major ion and stable isotope tracers to assess the sources of water in high flow events in streams in southeast Australia. The concentrations of most of the major ions and EC values either remained relatively constant during the high flow events or displayed non-systematic variations with respect to flow. Oxygen isotopes do vary systematically during the events, but the magnitude of the variation is Tritium activities increased from 1.4 to 1.5 TU to up to 2.4 TU close to the peak in streamflow and then decline over several days to pre-high flow levels. The peak tritium activities in the stream are lower than the tritium activity of the rainfall that generated the high flow events (2.7 to 2.8 TU) but within the range of tritium activities commonly recorded in soil water in southeast Australia (2.0 to 2.6 TU). The combined geochemical data imply that there is significant input from water stores other than groundwater during the high flow events. This is most likely to include a significant component of water displaced from the soils or regolith that typically has a residence time of 1 to 5 years. The major ion geochemistry of this water, especially its nitrate concentrations, is distinct from both groundwater and rainfall reflecting biogeochemical reactions in the soil zone/regolith. More generally, this study illustrates that since catchments contain multiple stores of water

  5. Democratic parenting: paradoxical messages in democratic parent education theories

    Science.gov (United States)

    Oryan, Shlomit; Gastil, John

    2013-06-01

    Some prominent parent education theories in the United States and other Western countries base their educational viewpoint explicitly on democratic values, such as mutual respect, equality and personal freedom. These democratic parenting theories advocate sharing power with children and including them in family decision making. This study presents a textual analysis of two such theories, the Adlerian model of parent education and the Parent Effectiveness Training (PET) model, as they are embodied in two original bestselling textbooks. Through content and argumentation analysis of these influential texts, this study examines the paradoxes inherent in these two theories when they articulate how to implement fully democratic principles within the parent-child relationship. We discover that in spite of their democratic rationale, both books offer communication practices that guide the child to modify misbehaviour, enforce parental power, and manipulate the child to make decisions that follow parental judgment, and thus do not endorse the use of a truly democratic parenting style. We suggest, as an alternative to the democratic parenting style, that parents be introduced to a guardianship management style, in which they do not share authority with children, but seek opportunities for enabling children to make more autonomous decisions and participate in more family decision making.

  6. Stishovite paradox in genesis of the superdeep diamond

    Science.gov (United States)

    Litvin, Yuriy

    2013-04-01

    O - SiO2 - FeO - CaSiO3 system where Ca-perovskite is stable. Thus, the "stishovite paradox" has physicochemical substantiation. Fractional crystallization of magnesiowustite in ultrabasic lower-mantle magma could lead to a rise of FeO content in the residual melts and activate the peritectic mechanism of the "stishovite paradox' formation. This is resulted in a transfer to basic residual melts and in situ formation of stishovite-magnesiowustite-Ca-perovskite rocks where stishovite is a primary lower-mantle mineral. This mechanism can be extended to the origin of stishovite and "stishovite paradox" in the superdeep diamond inclusions. By mantle-carbonatite model [5], the parental media of upper-mantle diamonds and inclusions are presented by carbonate-silicate-carbon melts. Carbonate-based parental media are applicable to origin of lower-mantle superdeep diamonds and inclusions. In this case the reasons arise from the presence of primary Na-, Mg-, Fe-, Ca-carbonate inclusions in superdeep diamonds and experimental evidence for congruent melting of carbonates under PT-conditions of the lower mantle [6, 7]. Support: RFBR grant 11-05-00401. 1. Stishov S.M., Popova S.V. (1961). Doklady USSR Academy of Sciences ????? 2. Kaminsky F. (2012). Earth-Science Review 110 . 127-147. 3. Akaogi M. ln E. Ohtani, ed. Advances in High-Pressure Mineralogy: Geological Society of America Special Paper 2007. # 421. P. 1-13. 4. Litvin Yu.A. Doklady Earth Sciences, 2013 (accepted). 5. Litvin Yu.A. ln E. Ohtani, ed. Advances in High-Pressure Mineralogy: Geological Society of America Special Paper 2007. # 421. P.83-103. 6. Spivak A.V., Litvin Yu.A., S.V. Ovsyannikov, et al. // Journal of Solid State Chemistry 2012,. 191, 102-106. 7. Solopova N.A., Litvin Yu.A., Spivak A.V. et al. Doklady Earth Sciences, 2013 (accepted).

  7. [Dream in the land of paradoxical sleep].

    Science.gov (United States)

    Pire, E; Herman, G; Cambron, L; Maquet, P; Poirrier, R

    2008-01-01

    Paradoxical sleep (PS or REM sleep) is traditionally a matter for neurophysiology, a science of the brain. Dream is associated with neuropsychology and sciences of the mind. The relationships between sleep and dream are better understood in the light of new methodologies in both domains, particularly those of basic neurosciences which elucidate the mechanisms underlying SP and functional imaging techniques. Data from these approaches are placed here in the perspective of rather old clinical observations in human cerebral lesions and in the phylogeny of vertebrates, in order to support a theory of dream. Dreams may be seen as a living marker of a cognitivo-emotional process, called here "eidictic process", involving posterior brain and limbic structures, keeping up during wakefulness, but subjected, at that time, to the leading role of a cognitivo-rational process, called here "thought process". The last one is of instrumental origin in human beings. It involves prefrontal cortices (executive tasks) and frontal/parietal cortices (attention) in the brain. Some clinical implications of the theory are illustrated.

  8. Collective Intelligence, Data Routing and Braess' Paradox

    CERN Document Server

    Tumer, K; 10.1613/jair.995

    2011-01-01

    We consider the problem of designing the the utility functions of the utility-maximizing agents in a multi-agent system so that they work synergistically to maximize a global utility. The particular problem domain we explore is the control of network routing by placing agents on all the routers in the network. Conventional approaches to this task have the agents all use the Ideal Shortest Path routing Algorithm (ISPA). We demonstrate that in many cases, due to the side-effects of one agent's actions on another agent's performance, having agents use ISPA's is suboptimal as far as global aggregate cost is concerned, even when they are only used to route infinitesimally small amounts of traffic. The utility functions of the individual agents are not "aligned" with the global utility, intuitively speaking. As a particular example of this we present an instance of Braess' paradox in which adding new links to a network whose agents all use the ISPA results in a decrease in overall throughput. We also demonstrate th...

  9. Orígenes: um pensador paradoxal?

    Directory of Open Access Journals (Sweden)

    Rogério Miranda de Almeida

    2016-01-01

    Full Text Available Estas reflexões têm como objetivo principal mostrar o caráter essencialmente paradoxal do pensamento de Orígenes. Na verdade, este paradoxo se desdobra no pensador alexandrino sob uma dupla modalidade: no seu pensamento e na experiência mesma da sua escrita, que é inseparável daquele. Consideramos, com efeito, que a escrita, enquanto espaço de resistências pelas quais se desenrola o desejo, não somente manifesta o pensamento de um autor, mas também determina este pensamento e, ao mesmo tempo, é por ele determinada. Na realidade, esta questão poderia ser aplicada não somente a Orígenes, mas também a todo pensador, ou melhor, a todo escritor. Em Orígenes, porém, esta problemática assume uma importância particular, na medida em que, sendo ele um exegeta e um escritor, ele se empenha em analisar e entender a relação entre fé e razão, ou “sabedoria cristã” e “sabedoria pagã”.

  10. Duodenal Intracellular Bicarbonate and the 'CF Paradox'

    Directory of Open Access Journals (Sweden)

    Kaunitz JD

    2001-07-01

    Full Text Available HCO(3(- secretion, which is believed to neutralize acid within the mucus gel, is the most studied duodenal defense mechanism. In general, HCO(3(- secretion rate and mucosal injury susceptibility correlate closely. Recent studies suggest that luminal acid can lower intracellular pH (pH(i of duodenal epithelial cells and that HCO(3(- secretion is unchanged during acid stress. Furthermore, peptic ulcers are rare in cystic fibrosis (CF, although, with impaired HCO(3(- secretion, increased ulcer prevalence is predicted, giving rise to the 'CF Paradox'. We thus tested the hypothesis that duodenal epithelial cell protection occurs as the result of pH(i regulation rather than by neutralization of acid by HCO(3(- in the pre-epithelial mucus. Cellular acidification during luminal acid perfusion, and unchanged HCO(3(- secretion during acid stress are inconsistent with pre-epithelial acid neutralization by secreted HCO(3(-. Furthermore, inhibition of HCO(3(- secretion by 5-nitro-2-(3-phenylpropylamino benzoic acid (NPPB despite preservation of pH(i and protection from acid-induced injury further question the pre-epithelial acid neutralization hypothesis. This decoupling of HCO(3(- secretion and injury susceptibility by NPPB (and possibly by CF further suggest that cellular buffering, rather than HCO(3(- exit into the mucus, is of primary importance for duodenal mucosal protection, and may account for the lack of peptic ulceration in CF patients.

  11. The autophagic paradox in cancer therapy.

    Science.gov (United States)

    Wu, W K K; Coffelt, S B; Cho, C H; Wang, X J; Lee, C W; Chan, F K L; Yu, J; Sung, J J Y

    2012-02-23

    Autophagy, hallmarked by the formation of double-membrane bound organelles known as autophagosomes, is a lysosome-dependent pathway for protein degradation. The role of autophagy in carcinogenesis is context dependent. As a tumor-suppressing mechanism in early-stage carcinogenesis, autophagy inhibits inflammation and promotes genomic stability. Moreover, disruption of autophagy-related genes accelerates tumorigenesis in animals. However, autophagy may also act as a pro-survival mechanism to protect cancer cells from various forms of cellular stress. In cancer therapy, adaptive autophagy in cancer cells sustains tumor growth and survival in face of the toxicity of cancer therapy. To this end, inhibition of autophagy may sensitize cancer cells to chemotherapeutic agents and ionizing radiation. Nevertheless, in certain circumstances, autophagy mediates the therapeutic effects of some anticancer agents. Data from recent studies are beginning to unveil the apparently paradoxical nature of autophagy as a cell-fate decision machinery. Taken together, modulation of autophagy is a novel approach for enhancing the efficacy of existing cancer therapy, but its Janus-faced nature may complicate the clinical development of autophagy modulators as anticancer therapeutics.

  12. Marketing human organs: the autonomy paradox.

    Science.gov (United States)

    Marshall, P A; Thomasma, D C; Daar, A S

    1996-03-01

    The severe shortage of organs for transplantation and the continual reluctance of the public to voluntarily donate has prompted consideration of alternative strategies for organ procurement. This paper explores the development of market approaches for procuring human organs for transplantation and considers the social and moral implications of organ donation as both a "gift of life" and a "commodity exchange." The problematic and paradoxical articulation of individual autonomy in relation to property rights and marketing human body parts is addressed. We argue that beliefs about proprietorship over human body parts and the capacity to provide consent for organ donation are culturally constructed. We contend that the political and economic framework of biomedicine, in western and non-western nations, influences access to transplantation technology and shapes the form and development of specific market approaches. Finally, we suggest that marketing approaches for organ procurement are and will be negotiated within cultural parameters constrained by several factors: beliefs about the physical body and personhood, religious traditions, economic conditions, and the availability of technological resources.

  13. "Obesity paradox" in coronary artery disease.

    Science.gov (United States)

    Akin, Ibrahim; Nienaber, Christoph A

    2015-10-26

    Obesity used to be among the more neglected public health problems, but has unfolded as a growing medical and socioeconomic burden of epidemic proportions. Morbid obesity is linked to traditional cardiovascular risk factors like, hypertension, hyperlipidemia and diabetes, and suspected to incur increased morbidity and mortality in the Western and even third world populations. This patient cohort is also at greater risk to develop coronary artery disease. Recent population-based registries revealed that 43% and 24% of all cases of coronary revascularization were carried out in overweight and obese patients, respectively. However, despite evidence of a positive correlation between obesity and increased cardiovascular morbidity, some authors have described a better clinical outcome in overweight and obese patients, a phenomenon they coined "obesity paradoxon". Thus, there is an ongoing debate in light of conflicting data and the possibility of confounding bias causing misconception and challenging the "obesity paradox". In this review article we present the current evidence and throughly discuss the validity of the "obesity paradoxon" in a variety of clinical settings.

  14. Paradoxical sleep deprivation increases plasma endothelin levels

    Directory of Open Access Journals (Sweden)

    B.D. Palma

    2002-01-01

    Full Text Available The endothelins (ET-1, 2 and 3 constitute a family of 21 amino acid peptides with potent biological activities. ET-1 is one of the most potent endogenous vasoconstrictors so far identified and its increased concentration in plasma appears to be closely related to the pathogenesis of arterial hypertension as well as to obstructive sleep apnea (OSA. OSA patients exhibit repetitive episodes of apnea and hypopnea that result in hypoxia and consecutive arousals. These patients are chronically sleep deprived, which may aggravate the hypertensive features, since literature data show that sleep deprivation results in hypertension both in humans and in animals. Based on the reported relationship between ET-1, hypertension and sleep deprivation consequences, the purpose of the present study was to determine plasma ET concentrations in paradoxical sleep-deprived animals. Male Wistar rats, 3 to 4 months old (N = 10 per group, were deprived of sleep for 24 and 96 h by the platform technique and plasma ET-1/2 was measured by radioimmunoassay. Analysis of plasma revealed that 96 h of sleep deprivation induced a significant increase in ET-1/2 release (6.58 fmol/ml compared to control (5.07 fmol/ml. These data show that sleep deprivation altered plasma ET-1/2 concentrations, suggesting that such an increase may participate in the genesis of arterial hypertension and cardiorespiratory changes observed after sleep deprivation.

  15. Variational Principles, Occam Razor and Simplicity Paradox

    Science.gov (United States)

    Berezin, Alexander A.

    2004-05-01

    Variational minimum principles (VMP) refer to energy (statics, Thomson and Earnshaw theorems in electrostatics), action (Maupertuis, Euler, Lagrange, Hamilton), light (Fermat), quantum paths (Feynman), etc. Historically, VMP appeal to some economy in nature, similarly to Occam Razor Parsimony (ORP) principle. Version of ORP are "best world" (Leibniz), Panglossianism (Voltaire), and "most interesting world" (Dyson). Conceptually, VMP exemplify curious fact that infinite set is often simpler than its subsets (e.g., set of all integers is simpler than set of primes). Algorithmically very simple number 0.1234567... (Champernowne constant) contains Library of Babel of "all books" (Borges) and codes (infinitely many times) everything countably possible. Likewise, full Megaverse (Everett, Deutsch, Guth, Linde) is simpler than our specific ("Big Bang") universe. Dynamically, VMP imply memory effects akin to hysteresis. Similar ideas are "water memory" (Benveniste, Josephson) and isotopic biology (Berezin). Paradoxically, while ORP calls for economy (simplicity), unfolding of ORP in VMP seemingly works in the opposite direction allowing for complexity emergence (e.g., symmetry breaking in Jahn-Teller effect). Metaphysical extrapolation of this complimentarity may lead to "it-from-bit" (Wheeler) reflection of why there is something rather than nothing.

  16. On probability, indeterminism and quantum paradoxes

    CERN Document Server

    Galvan, B

    2004-01-01

    If the quantum mechanical description of reality is not complete and a hidden variable theory is possible, what arises is the problem to explain where the rates of the outcomes of statistical experiments come from, as already noticed by Land\\'e and Popper. In this paper this problem is investigated, and a new "paradigm" about the nature of dynamical and statistical laws is proposed. In spite of its mathematical simplicity, this paradigm proposes some concepts which contrast with the usual intuitive view of evolution and of physical law, such as: initial conditions could play no privileged role in determining the evolution of the universe; the statistical distribution of the particles emitted by a source could depend on the future interactions of the particles; indeterministic trajectories can be defined by the least action principle. This paradigm is applied to the analysis of the two slits experiment and of the EPR paradox, and a coherent picture for these phenomena is proposed; this new picture could show h...

  17. Clouds and the Faint Young Sun Paradox

    CERN Document Server

    Goldblatt, Colin

    2011-01-01

    We investigate the role which clouds could play in resolving the Faint Young Sun Paradox (FYSP). Lower solar luminosity in the past means that less energy was absorbed on Earth (a forcing of -50 Wm-2 during the late Archean), but geological evidence points to the Earth being at least as warm as it is today, with only very occasional glaciations. We perform radiative calculations on a single global mean atmospheric column. We select a nominal set of three layered, randomly overlapping clouds, which are both consistent with observed cloud climatologies and reproduce the observed global mean energy budget of Earth. By varying the fraction, thickness, height and particle size of these clouds we conduct a wide exploration of how changed clouds could affect climate, thus constraining how clouds could contribute to resolving the FYSP. Low clouds reflect sunlight but have little greenhouse effect. Removing them entirely gives a~forcing of +25 Wm-2 whilst more modest reduction in their efficacy gives a forcing of +10 ...

  18. Aristotle vs. Plato: The Balkans' Paradoxical Enlightenment

    Directory of Open Access Journals (Sweden)

    D. Michalopoulos

    2007-09-01

    Full Text Available As it occurred in West, Aristotle’s thought was in Byzantium the main organon of philosophical meditation within the frame of the Christian Faith. Nonetheless, from the ninth century on it was a revival of Platonism that took place – of Neo-Platonism at the beginning and of Platonism itself at the end. The Church, initially indifferent, became suspicious only when, at the turning of the fourteenth to the fifteenth century, the Platonism seemed to engender somewhat a latent paganism; but the Patriarchate was not then able to fight that tendency. So only after the 1453 capture of Constantinople by the Ottomans, Gennadius Scholarius managed to root out from the Greek lands Platonism and its crypto-pagan extension. Be that as it may; the main paradox of the Balkan history is that in the early seventeenth century some leading Greek scholars endorsed the materialist interpretation of Aristotle’s thought – as it was taught in the University of Padua by Cesare Cremonini; and as a corollary this materialistic philosophical system began being taught in both Constantinople and Athens. It was that very way that the Enlightenment took birth in the Balkans – and somehow became a State ideology - long before its prevalence in France. And of course all this had as a result a turn toward Physics and Chemistry with far-reaching consequences

  19. The inflammation paradox in the evolution of mammalian pregnancy: turning a foe into a friend.

    Science.gov (United States)

    Chavan, Arun Rajendra; Griffith, Oliver William; Wagner, Günter Paul

    2017-08-26

    A widely discussed physiological puzzle of mammalian pregnancy is the immunological paradox, which asks: why is the semi-allogenic fetus not attacked by the mother's adaptive immune system? Here, we argue that an additional, and perhaps more fundamental paradox is the question: why is embryo implantation so similar to inflammation while inflammation is also the greatest threat to the continuation of pregnancy? Equally puzzling is the question of how this arose during evolution. We call this the inflammation paradox. We argue that acute endometrial inflammation was ancestrally a natural maternal reaction to the attaching blastocyst, a situation still observed in the opossum. Eutherian implantation arose through a transformation of the acute inflammation into a process essential for implantation by causing vascular permeability and matrix reorganization as well as by suppressing the effects deleterious to the fetus. We propose that this model allows us to understand the differences between 'good inflammation' and 'bad inflammation'. Further, it allows us to understand the influence of inflammation on the outcome of pregnancy and maternal health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Effects of behavioral patterns and network topology structures on Parrondo’s paradox

    Science.gov (United States)

    Ye, Ye; Cheong, Kang Hao; Cen, Yu-wan; Xie, Neng-gang

    2016-01-01

    A multi-agent Parrondo’s model based on complex networks is used in the current study. For Parrondo’s game A, the individual interaction can be categorized into five types of behavioral patterns: the Matthew effect, harmony, cooperation, poor-competition-rich-cooperation and a random mode. The parameter space of Parrondo’s paradox pertaining to each behavioral pattern, and the gradual change of the parameter space from a two-dimensional lattice to a random network and from a random network to a scale-free network was analyzed. The simulation results suggest that the size of the region of the parameter space that elicits Parrondo’s paradox is positively correlated with the heterogeneity of the degree distribution of the network. For two distinct sets of probability parameters, the microcosmic reasons underlying the occurrence of the paradox under the scale-free network are elaborated. Common interaction mechanisms of the asymmetric structure of game B, behavioral patterns and network topology are also revealed. PMID:27845430

  1. Rogers' paradox recast and resolved: population structure and the evolution of social learning strategies.

    Science.gov (United States)

    Rendell, Luke; Fogarty, Laurel; Laland, Kevin N

    2010-02-01

    We explore the evolution of reliance on social and asocial learning using a spatially explicit stochastic model. Our analysis considers the relative merits of four evolved strategies, two pure strategies (asocial and social learning) and two conditional strategies (the "critical social learner," which learns asocially only when copying fails, and the "conditional social learner," which copies only when asocial learning fails). We find that spatial structure generates outcomes that do not always conform to the finding of earlier theoretical analyses that social learning does not enhance average individual fitness at equilibrium (Rogers' paradox). Although we describe circumstances under which the strategy of pure social learning increases the average fitness of individuals, we find that spatial structure introduces a new paradox, which is that social learning can spread even when it decreases the average fitness of individuals below that of asocial learners. We also show that the critical social learner and conditional social learner both provide solutions to the aforementioned paradoxes, although we find some conditions in which pure (random) social learning out-competes both conditional strategies. Finally, we consider the relative merits of critical and conditional social learning under various conditions.

  2. Epidemiological Paradox or Immigrant Vulnerability? Obesity Among Young Children of Immigrants

    Science.gov (United States)

    Baker, Elizabeth H.; Rendall, Michael S.; Weden, Margaret M.

    2015-01-01

    According to the “immigrant epidemiological paradox,” immigrants and their children enjoy health advantages over their U.S.-born peers—advantages that diminish with greater acculturation. We investigated child obesity as a potentially significant deviation from this paradox for second-generation immigrant children. We evaluated two alternate measures of mother's acculturation: age at arrival in the United States and English language proficiency. To obtain sufficient numbers of second-generation immigrant children, we pooled samples across two related, nationally representative surveys. Each included measured (not parent-reported) height and weight of kindergartners. We also estimated models that alternately included and excluded mother's pre-pregnancy weight status as a predictor. Our findings are opposite to those predicted by the immigrant epidemiological paradox: children of U.S.-born mothers were less likely to be obese than otherwise similar children of foreign-born mothers; and the children of the least-acculturated immigrant mothers, as measured by low English language proficiency, were the most likely to be obese. Foreign-born mothers had lower (healthier) pre-pregnancy weight than U.S.-born mothers, and this was protective against their second-generation children's obesity. This protection, however, was not sufficiently strong to outweigh factors associated or correlated with the mothers' linguistic isolation and marginal status as immigrants. PMID:26111970

  3. Obesity Paradox in Recurrent Attacks of Gout in Observational Studies: Clarification and Remedy.

    Science.gov (United States)

    Nguyen, Uyen-Sa D T; Zhang, Yuqing; Louie-Gao, Qiong; Niu, Jingbo; Felson, David T; LaValley, Michael P; Choi, Hyon K

    2017-04-01

    Obesity is strongly associated with incident gout risk, but its association with the risk of recurrent gout attacks has been null or weak, constituting an obesity paradox. We sought to demonstrate and overcome the methodologic issues associated with the obesity paradox for risk of recurrent gout attacks. Using the Multiple Risk Factor Intervention Trial database, we decomposed the total effect of obesity into its direct and indirect (i.e., mediated) effects using marginal structural models. We also estimated the total effect of body mass index (BMI) change from baseline among incident gout patients. Of 11,816 gout-free subjects at baseline, we documented 408 incident gout cases, with 132 developing recurrent gout attacks over a 7-year followup period. The adjusted odds ratio (OR) for incident gout among obese individuals was 2.6, whereas that for recurrent gout attacks among gout patients was 0.98 (i.e., the obesity paradox). These ORs correlated well with the ORs for the indirect and direct effects of obesity on the risk of recurrent gout attacks (2.83 and 0.98, respectively). Compared with no BMI change, the OR of increasing versus decreasing >5% of baseline BMI was 0.61 and 1.60 for recurrent gout attacks, respectively (P for trend paradox for the risk of recurrent gout attacks is explained by the absence of the direct effect, which is often measured in conventional analyses and misinterpreted as the intended total effect of interest. In contrast, the BMI change analysis correctly estimated the intended total effect of BMI, and revealed a dose-response relationship. © 2016, American College of Rheumatology.

  4. Oxford and the Savannah: can the hippo provide an explanation for Peto's paradox?

    Science.gov (United States)

    Kelleher, Fergal C; O'Sullivan, Hazel

    2014-02-01

    Peto's paradox is the counterintuitive finding that increasing body mass and thereby cell number does not correlate with an increase in cancer incidence across different species. The Hippo signaling pathway is an evolutionarily conserved system that determines organ size by regulating apoptosis and cell proliferation. It also affects cell growth by microRNA-29 (miR-29)-mediated cross-talk to the mTOR signaling pathway. Whether these pathways that decide organ size could explain this paradox merits consideration. Inactivation of most genes of the Hippo pathway in Drosophila melanogaster genetic screens causes excessive tissue-specific growth of developing tissues. Altered Hippo pathway activity is frequently found in diverse tumor types, but mutations of component pathway genes are rare. Most Hippo pathway components are encoded by tumor suppressor genes (TSG), but an exception is the downstream effector gene called YAP. Activity of the Hippo pathway causes deactivating phosphorylation of YES-associated protein (YAP) with nuclear exclusion. YAP can also be phosphorylated at a second site, S127, by AKT. YAP induces the expression of genes responsible for proliferation and suppression of apoptosis. Resolving Peto's paradox may serendipitously provide new insights into the biology and treatment of cancer. This article considers Hippo signaling and Peto's paradox in the context of TSG-oncogene computed models. Interspecies differences in dietary composition, metabolic rates, and anabolic processes are also discussed in the context of Hippo-mTOR signaling. The metabolically important LKB1-AMPK (liver kinase B1-AMP activated protein kinase) signaling axis that suppresses the mTOR pathway is also considered.

  5. Adiposopathy, "sick fat," Ockham's razor, and resolution of the obesity paradox.

    Science.gov (United States)

    Bays, Harold

    2014-05-01

    Among lean populations, cardiovascular disease (CVD) is rare. Among those with increased adiposity, CVD is the commonest cause of worldwide death. The "obesity paradox" describes seemingly contrary relationships between body fat and health/ill-health. Multiple obesity paradoxes exist, and include the anatomic obesity paradox, physiologic obesity paradox, demographic obesity paradox, therapeutic obesity paradox, cardiovascular event/procedure obesity paradox, and obesity treatment paradox. Adiposopathy ("sick fat") is defined as adipocyte/adipose tissue dysfunction caused by positive caloric balance and sedentary lifestyle in genetically and environmentally susceptible individuals. Adiposopathy contributes to the commonest metabolic disorders encountered in clinical practice (high glucose levels, high blood pressure, dyslipidemia, etc.), all major CVD risk factors. Ockham's razor is a principle of parsimony which postulates that among competing theories, the hypothesis with the fewest assumptions is the one best selected. Ockham's razor supports adiposopathy as the primary cause of most cases of adiposity-related metabolic diseases, which in turn helps resolve the obesity paradox.

  6. Carbonate mound reservoirs in the paradox formation: An outcrop analogue along the San Juan River, Southeastern Utah

    Energy Technology Data Exchange (ETDEWEB)

    Chidsey, T. C. Jr.; Morgan, C.D. [Utah Geological Survey, Salt Lake City, UT (United States); Eby, D.E. [Eby Petrography & Consulting, Inc., Littleton, CO (United States)] [and others

    1996-06-01

    Carbonate mound reservoirs within the Pennsylvanian (Desmoinesian) Paradox Formation are major producers of oil and gas in the Paradox basin of Utah, Colorado, and Arizona. Outcrops of the Paradox Formation along the San Juan River of southeastern Utah provide small-scale analogues of reservoir heterogeneity, flow barriers and baffles, lithofacies, and geometry. These characteristics can be used in reservoir simulation models for secondary/tertiary recovery of oil from small fields in the basin. Exposures of the Paradox Formation Ismay zone in the Wild Horse Canyon area display lateral facies changes from phylloid algal mounds to off-mound detrital wedges or fans bounded at the top by a flooding surface. The phylloid mounds are composed of bafflestone, skeletal grainstone, packstone, and cementstone. Algal plates, brachiopods, bryozoans, and rugose corals are commonly found in the phylloid mounds. The mound wall is composed of rudstone, lumpstone, and cementstone. The detrital fan consists of transported algal material, grainstone, and mudstone with open-marine fossils. Within the mound complex is an inter-mound trough tentatively interpreted to be a tidal channel. The geometry and composition of the rocks in the trough significantly add to the overall heterogeneity of the mound. Reservoir models are being developed for possible water- and carbon-dioxide floods of small Paradox basin fields to determine the most effective secondary/tertiary recovery method. The models will include lithologic fabrics, flooding surfaces, and inter-mound troughs, based on the mound complex exposed at Wild Horse Canyon. This project may also provide reservoir information for simulation models in small Paleozoic carbonate mound fields in other basins worldwide.

  7. Spatial heterogeneity can resolve the nitrogen paradox of tropical forests.

    Science.gov (United States)

    Menge, Duncan N L; Levin, Simon A

    2017-01-10

    Many tropical forests are characterized by large losses of plant-available forms of nitrogen (N), indicating that they are N-rich, and by an abundance of plants capable of symbiotic N fixation. These N-fixing plants can fix enough N to drive N-richness. However, biological N fixation (BNF) is more expensive than using plant-available N, so sustained BNF in N-rich soils appears to be a paradox. Here, we use spatially explicit ecosystem models to analyze the conditions under which spatial heterogeneity can induce simultaneous BNF and loss of plant-available N (hereafter, we call this combination "N-rich BNF"). Spatial movement of litter to neighboring plants' rooting zones can maintain N-rich BNF under a variety of conditions. For example, when N-fixers have higher N demand than non-fixers, N-fixers export N-rich litter to non-fixers, inducing large losses of plant-available N from the ecosystem, and receive N-poor litter from non-fixers, inducing BNF. BNF and N loss fluxes increase in proportion to the ratio of N-fixer litter N:P to non-fixer litter N:P, and also in proportion to the fraction of litter transferred out of a tree's rooting zone. Stoichiometric variability augments N-rich BNF, as does increasing the fraction of the landscape occupied by N-fixers, at least when they are rare. On the contrary, greater root overlap between neighbors and clumping of N-fixers diminish N-rich BNF. Finally, we examined how spatial litter transfer interacts with another mechanism that can sustain N-rich BNF, incomplete down-regulation of BNF. Spatial transfer and incomplete down-regulation can both sustain N-rich BNF, but they are compensatory rather than additive. These mechanisms can be distinguished by examining where N losses occur. Incomplete down-regulation of BNF leads to greater N loss under N-fixing trees, whereas spatial litter transfer leads to greater N loss under non-fixing trees. Along with time lags in regulating BNF, these results comprise a series of

  8. Obesity paradox in end-stage kidney disease patients.

    Science.gov (United States)

    Park, Jongha; Ahmadi, Seyed-Foad; Streja, Elani; Molnar, Miklos Z; Flegal, Katherine M; Gillen, Daniel; Kovesdy, Csaba P; Kalantar-Zadeh, Kamyar

    2014-01-01

    In the general population, obesity is associated with increased cardiovascular risk and decreased survival. In patients with end-stage renal disease (ESRD), however, an "obesity paradox" or "reverse epidemiology" (to include lipid and hypertension paradoxes) has been consistently reported, i.e. a higher body mass index (BMI) is paradoxically associated with better survival. This survival advantage of large body size is relatively consistent for hemodialysis patients across racial and regional differences, although published results are mixed for peritoneal dialysis patients. Recent data indicate that both higher skeletal muscle mass and increased total body fat are protective, although there are mixed data on visceral (intra-abdominal) fat. The obesity paradox in ESRD is unlikely to be due to residual confounding alone and has biologic plausibility. Possible causes of the obesity paradox include protein-energy wasting and inflammation, time discrepancy among competitive risk factors (undernutrition versus overnutrition), hemodynamic stability, alteration of circulatory cytokines, sequestration of uremic toxin in adipose tissue, and endotoxin-lipoprotein interaction. The obesity paradox may have significant clinical implications in the management of ESRD patients especially if obese dialysis patients are forced to lose weight upon transplant wait-listing. Well-designed studies exploring the causes and consequences of the reverse epidemiology of cardiovascular risk factors, including the obesity paradox, among ESRD patients could provide more information on mechanisms. These could include controlled trials of nutritional and pharmacologic interventions to examine whether gain in lean body mass or even body fat can improve survival and quality of life in these patients. © 2014.

  9. Paradoxical upregulation of glutamatergic presynaptic boutons during mild cognitive impairment.

    Science.gov (United States)

    Bell, Karen F S; Bennett, David A; Cuello, A Claudio

    2007-10-03

    Synaptic integrity is now recognized as a central component of Alzheimer's disease. Surprisingly, however, the structural status of glutamatergic synapses in Alzheimer's disease is unclear, despite the fact that glutamate is the major excitatory transmitter of the CNS and has key roles in excitotoxicity and long-term potentiation. The identification of specific markers of glutamatergic neurons now allows an assessment of the structural involvement of the glutamatergic system across progressive stages of the Alzheimer's pathology, an opportunity not afforded by previously used neurochemical approaches. Glutamatergic presynaptic bouton density and dystrophic neurite abundance were quantified in midfrontal gyrus brain tissue from subjects with no cognitive impairment, mild cognitive impairment, or mild- or severe-stage Alzheimer's disease. Our study demonstrates a striking pathology-dependent pattern of glutamatergic synaptic remodeling with disease progression. Subjects with mild cognitive impairment display a paradoxical elevation in glutamatergic presynaptic bouton density, a situation akin to that observed in the cholinergic system, which then depletes and drops with disease progression. This pattern of synaptic remodeling mirrors our previous findings in transgenic animal models and is of major relevance to current transmitter-based therapeutics.

  10. Paradoxical Personality Scale: Its Development and Construct Validity Analysis

    Directory of Open Access Journals (Sweden)

    Agustín Freiberg Hoffmann

    2014-01-01

    Full Text Available The development and construct validation process of the Paradoxical Personality Scale is presented in this paper. The concept assessed has been posed by Csikszentmihalyi (1996 and was described as related to creative individuals. Following his guidelines, 150 items were designed and judged by five experts, and later analysed from a facies standpoint. The resulting version was used in a sample of college students (n=473; 50.5% males, 49.5% females from 18 to 35 years ( = 21.82; DT= 3.14, to explore underlying dimensions. A 30item/6-factor solution was firstly isolated and after confirmed by a confirmatory factor analysis developed with 800 college students (44.4% males, 55.6% females, between18 and 35 years ( = 23.47; DT= 3.30. Both samples were selected from the population of college students from Buenos Aires, Argentina. Internal consistency and temporal stability of scores were also tested, obtaining adequate coefficients in both cases, in view of the composition of the dimensions underlying the construct analysed. Results show acceptable psychometric properties as well as shortness and simplicity for data gathering, which are discussed taking into account theoretical models and new research lines.

  11. Different Roles for Contracture and Calpain in Calcium Paradox-Induced Heart Injury

    Science.gov (United States)

    Zhang, Jian-Ying; Bi, Sheng-Hui; Xu, Ming; Jin, Zhen-Xiao; Yang, Yang; Jiang, Xiao-Fan; Zhou, Jing-Jun

    2012-01-01

    The Ca2+ paradox represents a good model to study Ca2+ overload injury in ischemic heart diseases. We and others have demonstrated that contracture and calpain are involved in the Ca2+ paradox-induced injury. This study aimed to elucidate their roles in this model. The Ca2+ paradox was elicited by perfusing isolated rat hearts with Ca2+-free KH media for 3 min or 5 min followed by 30 min of Ca2+ repletion. The LVDP was measured to reflect contractile function, and the LVEDP was measured to indicate contracture. TTC staining and the quantification of LDH release were used to define cell death. Calpain activity and troponin I release were measured after Ca2+ repletion. Ca2+ repletion of the once 3-min Ca2+ depleted hearts resulted in almost no viable tissues and the disappearance of contractile function. Compared to the effects of the calpain inhibitor MDL28170, KB-R7943, an inhibitor of the Na+/Ca2+ exchanger, reduced the LVEDP level to a greater extent, which was well correlated with improved contractile function recovery and tissue survival. The depletion of Ca2+ for 5 min had the same effects on injury as the 3-min Ca2+ depletion, except that the LVEDP in the 5-min Ca2+ depletion group was lower than the level in the 3-min Ca2+ depletion group. KB-R7943 failed to reduce the level of LVEDP, with no improvement in the LVDP recovery in the hearts subjected to the 5-min Ca2+ depletion treatment; however, KB-R7943 preserved its protective effects in surviving tissue. Both KB-R7943 and MDL28170 attenuated the Ca2+ repletion-induced increase in calpain activity in 3 min or 5 min Ca2+ depleted hearts. However, only KB-R7943 reduced the release of troponin I from the Ca2+ paradoxic heart. These results provide evidence suggesting that contracture is the main cause for contractile dysfunction, while activation of calpain mediates cell death in the Ca2+ paradox. PMID:23284963

  12. Different roles for contracture and calpain in calcium paradox-induced heart injury.

    Directory of Open Access Journals (Sweden)

    Jian-Ying Zhang

    Full Text Available The Ca(2+ paradox represents a good model to study Ca(2+ overload injury in ischemic heart diseases. We and others have demonstrated that contracture and calpain are involved in the Ca(2+ paradox-induced injury. This study aimed to elucidate their roles in this model. The Ca(2+ paradox was elicited by perfusing isolated rat hearts with Ca(2+-free KH media for 3 min or 5 min followed by 30 min of Ca(2+ repletion. The LVDP was measured to reflect contractile function, and the LVEDP was measured to indicate contracture. TTC staining and the quantification of LDH release were used to define cell death. Calpain activity and troponin I release were measured after Ca(2+ repletion. Ca(2+ repletion of the once 3-min Ca(2+ depleted hearts resulted in almost no viable tissues and the disappearance of contractile function. Compared to the effects of the calpain inhibitor MDL28170, KB-R7943, an inhibitor of the Na(+/Ca(2+ exchanger, reduced the LVEDP level to a greater extent, which was well correlated with improved contractile function recovery and tissue survival. The depletion of Ca(2+ for 5 min had the same effects on injury as the 3-min Ca(2+ depletion, except that the LVEDP in the 5-min Ca(2+ depletion group was lower than the level in the 3-min Ca(2+ depletion group. KB-R7943 failed to reduce the level of LVEDP, with no improvement in the LVDP recovery in the hearts subjected to the 5-min Ca(2+ depletion treatment; however, KB-R7943 preserved its protective effects in surviving tissue. Both KB-R7943 and MDL28170 attenuated the Ca(2+ repletion-induced increase in calpain activity in 3 min or 5 min Ca(2+ depleted hearts. However, only KB-R7943 reduced the release of troponin I from the Ca(2+ paradoxic heart. These results provide evidence suggesting that contracture is the main cause for contractile dysfunction, while activation of calpain mediates cell death in the Ca(2+ paradox.

  13. Desire versus efficacy in smokers' paradoxical reactions to pictorial health warnings for cigarettes.

    Directory of Open Access Journals (Sweden)

    Daniel Romer

    Full Text Available Pictorial health warnings on cigarette packs create aversive emotional reactions to smoking and induce thoughts about quitting; however, contrary to models of health behavior change, they do not appear to alter intentions to quit smoking. We propose and test a novel model of intention to quit an addictive habit such as smoking (the efficacy-desire model that can explain this paradoxical effect. At the core of the model is the prediction that self-efficacy and desire to quit an addictive habit are inversely related. We tested the model in an online experiment that randomly exposed smokers (N = 3297 to a cigarette pack with one of three increasing levels of warning intensity. The results supported the model's prediction that despite the effects of warnings on aversion to smoking, intention to quit smoking is an inverted U-shape function of the smoker's self-efficacy for quitting. In addition, smokers with greater (lesser quit efficacy relative to smoking efficacy increase (decrease intentions to quit. The findings show that previous failures to observe effects of pictorial warning labels on quit intentions can be explained by the contradictory individual differences that warnings produce. Thus, the model explains the paradoxical finding that quit intentions do not change at the population level, even though smokers recognize the implications of warnings. The model suggests that pictorial warnings are effective for smokers with stronger quit-efficacy beliefs and provides guidance for how cigarette warnings and tobacco control strategies can be designed to help smokers quit.

  14. Quantum information paradox: Real or fictitious?

    Indian Academy of Sciences (India)

    Abhas Mitra

    2009-09-01

    One of the outstanding puzzles of theoretical physics is whether quantum information indeed gets lost in the case of black hole (BH) evaporation or accretion. Let us recall that quantum mechanics (QM) demands an upper limit on the acceleration of a test particle. On the other hand, it is pointed out here that, if a Schwarzschild BH exists, the acceleration of the test particle would blow up at the event horizon in violation of QM. Thus the concept of an exact BH is in contradiction with QM and quantum gravity (QG). It is also reminded that the mass of a BH actually appears as an integration constant of Einstein equations. And it has been shown that the value of this integration constant is actually zero! Thus even classically, there cannot be finite mass BHs though zero mass BH is allowed. It has been further shown that during continued gravitational collapse, radiation emanating from the contracting object gets trapped within it by the runaway gravitational field. As a consequence, the contracting body attains a quasi-static state where outward trapped radiation pressure gets balanced by inward gravitational pull and the ideal classical BH state is never formed in a finite proper time. In other words, continued gravitational collapse results in an `eternally collapsing object' which is a ball of hot plasma and which is asymptotically approaching the true BH state with = 0 after radiating away its entire mass energy. And if we include QM, this contraction must halt at a radius suggested by the highest QM acceleration. In any case no event horizon (EH) is ever formed and in reality, there is no quantum information paradox.

  15. Embolia paradojal inminente Impending paradoxical embolism

    Directory of Open Access Journals (Sweden)

    Miguel A. Veltri

    2006-12-01

    Full Text Available La presencia de un trombo venoso atrapado en un defecto interauricular e insinuándose en las cavidades izquierdas configura una forma extremadamente inusual de enfermedad tromboembólica denominada embolia paradojal inminente. Presentamos el caso de un varón de 71 años, sometido 10 días antes a adenomectomía prostática, que consultó por disnea y mareos. Se le diagnosticó tromboembolismo pulmonar bilateral por tomografía axial computada helicoidal. Se lo anticoaguló con heparina sódica y se le realizó un ecocardiograma transesofágico que mostró un trombo que atravesaba el foramen oval y se alojaba en la aurícula izquierda. No presentaba signos clínicos de embolización sistémica. Se realizó la embolectomía quirúrgica y cierre del defecto auricular. El paciente falleció.An intracardiac thrombus traversing a patent foramen ovale is a very infrequent but potentially catastrophic complication of the thromboembolic disease. It is named "impending paradoxical embolism". We report the case of a 71 year old Caucasian male warded in ten days after a prostatectomy because of bilateral pulmonary embolism. Diagnosis was confirmed by HCT scan and the patient received anticoagulation with heparin. A transesophageal ecocardiogram disclosed a thrombus traversing foramen ovale into the left atrium. Surgical embolectomy was performed, but the patient died shortly after surgery.

  16. The ABC-paradox: is Time Driven ABC relevant for small and Medium sized enterprises (SME)?

    DEFF Research Database (Denmark)

    Fladkjær, Henrik Find; Jensen, Erling

    Several articles suggest that Activity Based Costing (ABC) has failed to succeed in practical use. It is even argued that we have an ABC-paradox. Activity Based Costing has won theoretically in nu-merous articles in journals, through books, being included in all major Business Accounting text...... manufacturing company we will analyse whether it is possible to create a satisfactory decision making foundation using a TDABC as a less complex cost model in the company. We have analysed our way to the conclusion that compared to ABC, the TDABC model provides the management with a number of pragmatic...

  17. Fermi's Paradox Is a Daunting Problem, Under Whatever Label

    Science.gov (United States)

    Čirković, Milan M.

    2016-10-01

    Gray (2015) argued that the Fermi paradox (FP) is a misnomer, and it is not a valid paradox. Gray also speculated that the argument was misattributed to Fermi, whose lunchtime remarks did not pertain to the existence of extraterrestrial intelligence, but to the feasibility of interstellar travel. Instead, the paradox is ascribed to Hart and Tipler, and it is further suggested that the paradox is not a real problem or research subject and should not be used in debates about SETI projects. The arguments given are unpersuasive, ahistorical, and, in at least one instance, clearly hinge on literalistic and uncharitable reading of evidence. Instead, I argue the following three points: (i) Contrary to Gray's assertion, the historical issue of naming of ideas or concepts is completely divorced from their epistemic status. (ii) FP is easily and smoothly generalized into the Great Silence paradox, so it makes no sense either theoretically or empirically to separate the two. (iii) In sharp contrast to the main implication of Gray's paper, FP has become more aggravated lately due to advances in astrobiology.

  18. Fermi's Paradox Is a Daunting Problem---Under Whatever Label

    CERN Document Server

    Cirkovic, Milan M

    2016-01-01

    Gray (2015) argued that the Fermi paradox (FP) is a misnomer, and it is not a valid paradox. Gray also speculated that the argument was misattributed to Fermi, whose lunchtime remarks did not pertain to the existence of extraterrestrial intelligence, but to the feasibility of interstellar travel. Instead, the paradox is ascribed to Hart and Tipler, and it is further suggested that the paradox is not a real problem or research subject and should not be used in debates about SETI projects. The arguments given are unpersuasive, ahistorical, and, in at least one instance, clearly hinge on literalistic and uncharitable reading of evidence. Instead, I argue the following three points: (i) Contrary to Gray's assertion, the historical issue of naming of ideas or concepts is completely divorced from their epistemic status. (ii) FP is easily and smoothly generalized into the Great Silence paradox, so it makes no sense either theoretically or empirically to separate the two. (iii) In sharp contrast to the main implicati...

  19. Why We Must Continue to Investigate Menthol's Role in the African American Smoking Paradox.

    Science.gov (United States)

    Alexander, Linda A; Trinidad, Dennis R; Sakuma, Kari-Lyn K; Pokhrel, Pallav; Herzog, Thaddeus A; Clanton, Mark S; Moolchan, Eric T; Fagan, Pebbles

    2016-04-01

    The disproportionate burden of tobacco use among African Americans is largely unexplained. The unexplained disparities, referred to as the African American smoking paradox, includes several phenomena. Despite their social disadvantage, African American youth have lower smoking prevalence rates, initiate smoking at older ages, and during adulthood, smoking rates are comparable to whites. Smoking frequency and intensity among African American youth and adults are lower compared to whites and American Indian and Alaska Natives, but tobacco-caused morbidity and mortality rates are disproportionately higher. Disease prediction models have not explained disease causal pathways in African Americans. It has been hypothesized that menthol cigarette smoking, which is disproportionately high among African Americans, may help to explain several components of the African American smoking paradox. This article provides an overview of the potential role that menthol plays in the African American smoking paradox. We also discuss the research needed to better understand this unresolved puzzle. We examined prior synthesis reports and reviewed the literature in PubMed on the menthol compound and menthol cigarette smoking in African Americans. The pharmacological and physiological effects of menthol and their interaction with biological and genetic factors may indirectly contribute to the disproportionate burden of cigarette use and diseases among African Americans. Future studies that examine taste sensitivity, the menthol compound, and their effects on smoking and chronic disease would provide valuable information on how to reduce the tobacco burden among African Americans. Our study highlights four counterintuitive observations related to the smoking risk profiles and chronic disease outcomes among African Americans. The extant literature provides strong evidence of their existence and shows that long-standing paradoxes have been largely unaffected by changes in the social

  20. Paradoxes in virtual team knowledge communication and trust building

    DEFF Research Database (Denmark)

    Petersen, Nils Braad

    2012-01-01

    a need for a different, multi-level, multi-theoretical approach to virtual team research in order to overcome the paradoxes. A moderate constructionist research position building on Critical Realism is proposed. To situate the project within current literatures, trust, knowledge management and virtual...... team literatures are reviewed. These are used to support the paradoxes used as a lens for understanding. A research design is presented building on interviews, documentary analysis and observations analysed using Social Network Analysis and James Gee’s framework for discourse analysis. Finally......This thesis proposal presents paradoxes within current trust and knowledge management literatures as a lens for understanding challenges in virtual teams working across organisational and geographic boundaries. By exposing contradictions within current virtual team research, the author proposes...

  1. The paradox of enrichment in an adaptive world

    Science.gov (United States)

    Mougi, Akihiko; Nishimura, Kinya

    2008-01-01

    Paradoxically, enrichment can destabilize a predator–prey food web. While adaptive dynamics can greatly influence the stability of interaction systems, few theoretical studies have examined the effect of the adaptive dynamics of interaction-related traits on the possibility of resolution of the paradox of enrichment. We consider the evolution of attack and defence traits of a predator and two prey species in a one predator–two prey system in which the predator practises optimal diet use. The results showed that optimal foraging alone cannot eliminate a pattern of destabilization with enrichment, but trait evolution of the predator or prey can change the pattern to one of stabilization, implying a possible resolution of the paradox of enrichment. Furthermore, trait evolution in all species can broaden the parameter range of stabilization. Importantly, rapid evolution can stabilize this system, but weaken its stability in the face of enrichment. PMID:18700201

  2. Obesity and the obesity paradox in heart failure.

    Science.gov (United States)

    Clark, Adrienne L; Fonarow, Gregg C; Horwich, Tamara B

    2014-01-01

    Obesity is a growing public health problem in the general population, and significantly increases the risk for the development of new-onset heart failure (HF). However, in the setting of chronic HF, overweight and mild to moderate obesity is associated with substantially improved survival compared to normal-weight patients. Evidence exists for an "obesity paradox" in HF, with the majority of data measuring obesity by body mass index, but also across various less-frequently used measures of body fat (BF) and body composition including waist circumference, waist-hip ratio, skinfold estimates of percent BF, and bioelectrical impedance analysis of body composition. Other emerging areas of investigation such as the relationship of the obesity paradox to cardiorespiratory fitness are also discussed. Finally, this review explores various explanations for the obesity paradox, and summarizes the current evidence for intentional weight loss treatments for HF in context. © 2014.

  3. Ambiguity aversion in a delay analogue of the Ellsberg Paradox

    Directory of Open Access Journals (Sweden)

    Bethany J. Weber

    2012-07-01

    Full Text Available Decision makers are often ambiguity averse, preferring options with subjectively known probabilities to options with unknown probabilities. The Ellsberg paradox is the best-known example of this phenomenon. Ambiguity has generally been studied in the domain of risky choice, and many theories of ambiguity aversion deal with ambiguity only in this context. However, ambiguity aversion may occur in other contexts. In the present experiment, we examine the effects of ambiguity in intertemporal choice. Subjects imagine they are expecting a package and must choose between two delivery options. Some delivery times are exact. Others are ambiguous, with delivery possible over a range of dates. This problem was structurally identical to the Ellsberg paradox. Subjects showed the same pattern of responses as in the traditional Ellsberg paradox, with each delivery service preferred when it was the unambiguous option. Ambiguity aversion is not specific to risk, but can also occur in other domains.

  4. Obesity paradox in different populations: evidence and controversies.

    Science.gov (United States)

    Goel, Kashish; Lopez-Jimenez, Francisco; De Schutter, Alban; Coutinho, Thais; Lavie, Carl J

    2014-01-01

    An inverse association between BMI and mortality has been reported in patients with coronary heart disease and heart failure. This 'obesity paradox' has recently been reported in other disease states, including stroke, hypertension, incident diabetes, atrial fibrillation, hemodialysis and transcatheter aortic valve replacement. Cardiorespiratory fitness influences the obesity paradox and this inverse association may be present only in individuals with low fitness levels. Intentional weight loss, exercise training and improving lean mass are important and should be advised to all patients. Recent studies have also explored the association between measures of central obesity and direct measures of body fat with mortality. This review will summarize the evidence, controversies and mechanisms associated with the puzzling obesity paradox.

  5. 肿瘤悖论%Cancer paradox

    Institute of Scientific and Technical Information of China (English)

    张百红; 岳红云

    2016-01-01

    肿瘤的存在有其矛盾性。除了 Peto 悖论,肿瘤还有其他悖论:肿瘤是整体的一部分,却不受整体控制;肿瘤是抵抗衰老的方式,却加速死亡;肿瘤依赖人体而存在,却通过转移而最终杀灭人体。肿瘤存在的悖论提示调变肿瘤的价值。%Cancer existence is contradiction.Except Peto's paradox,cancer paradox includes that cancer is a part of the whole,but out of control.Cancer is a manner of age -resistance,but promoting death.Cancer depends on human body,but killing body through metastasis.Cancer paradox will provide the value of modulating cancer.

  6. The Charge-Magnet Paradoxes of Classical Electrodynamics

    CERN Document Server

    Mansuripur, Masud

    2014-01-01

    A number of charge-magnet paradoxes have been discussed in the literature, beginning with Shockley's famous 1967 paper, where he introduced the notion of hidden momentum in electromagnetic systems. We discuss all these paradoxes in a single, general context, showing that the conservation laws of linear and angular momenta can be satisfied without the need for hidden entities, provided that the Einstein-Laub laws of force and torque are used in place of the standard Lorentz law. Einstein and Laub published their paper in 1908, but the simplicity of the conventional Lorentz law overshadowed the subtle features of their formulation which, at first sight, appears somewhat complicated. However, that slight complication turns out to lead to subsequent advantages in light of Shockley's discovery of hidden momentum, which occurred more than a decade after Einstein had passed away. In this paper, we show how the Einstein-Laub formalism handles the underlying problems associated with certain paradoxes of classical elec...

  7. Sevoflurane protects ventricular myocytes from Ca2+ paradox-mediated Ca2+ overload by blocking the activation of transient receptor potential canonical channels.

    Science.gov (United States)

    Kojima, Akiko; Kitagawa, Hirotoshi; Omatsu-Kanbe, Mariko; Matsuura, Hiroshi; Nosaka, Shuichi

    2011-09-01

    Volatile anesthetics produce cardioprotective action by attenuating cellular Ca2+ overload. The Ca2+ paradox is an important model for studying the mechanisms associated with Ca2+ overload-mediated myocardial injury, and was recently found to be mediated by Ca2+ entry through the transient receptor potential canonical channels upon Ca2+ repletion. This study investigated the effect of sevoflurane on cellular mechanisms underlying the Ca2+ paradox. The Ca2+ paradox was examined in fluo-3 or mag-fluo-4-loaded mouse ventricular myocytes using confocal laser scanning microscope, upon Ca2+ repletion after 15 min of Ca2+ depletion in the absence and presence of sevoflurane. The Ca2+ paradox was evoked in approximately 65% of myocytes upon Ca2+ repletion, as determined by an abrupt elevation of cytosolic Ca2+ accompanied by hypercontracture. The Ca2+ paradox was significantly suppressed by sevoflurane administered for 3 min before and during Ca2+ repletion (Post) or during Ca2+ depletion and repletion (Postlong), and Postlong was more beneficial than Post application. The sarcoplasmic reticulum Ca2+ levels gradually decreased during Ca2+ depletion, and the Ca2+ paradox was readily evoked in myocytes with reduced sarcoplasmic reticulum Ca2+ levels. Postlong but not Post application of sevoflurane prevented decrease in sarcoplasmic reticulum Ca2+ levels by blocking Ca2+ leak through ryanodine receptors. Whole cell patch-clamp recordings revealed that sevoflurane rapidly blocked thapsigargin-induced transient receptor potential canonical currents. Sevoflurane protects ventricular myocytes from Ca2+ paradox-mediated Ca2+ overload by blocking transient receptor potential canonical channels and by preventing the decrease in sarcoplasmic reticulum Ca2+ levels, which is associated with less activation of transient receptor potential canonical channels.

  8. Paradoxical Embolization in an Adult Cystic Fibrosis Patient

    Directory of Open Access Journals (Sweden)

    Nabil M Al Lawati

    2007-01-01

    Full Text Available Cystic fibrosis patients with an implantable venous access device (IVAD and a patent foramen ovale (PFO are at an increased risk of developing paradoxical embolism. A 33-year-old patient who had a cerebrovascular accident in the above setting is described. She had been anticoagulated because she had thrombosis of the tip of the indwelling catheter, and her PFO was closed percutaneuosly followed by replacement of her IVAD. She made a full neurological recovery. Echocardiography and prophylactic closure of the PFO, when present, as primary prevention for paradoxical embolism may be warranted in cystic fibrosis patients before placement of an IVAD.

  9. The calcium paradox - What should we have to fear?

    Science.gov (United States)

    de Oliveira, Marcos Aurélio Barboza; Brandi, Antônio Carlos; dos Santos, Carlos Alberto; Botelho, Paulo Henrique Husseni; Cortez, José Luís Lasso; Goissis, Gilberto; Braile, Domingo Marcolino

    2014-01-01

    The calcium paradox was first mentioned in 1966 by Zimmerman et al. Thereafter gained great interest from the scientific community due to the fact of the absence of calcium ions in heart muscle cells produce damage similar to ischemia-reperfusion. Although not all known mechanisms involved in cellular injury in the calcium paradox intercellular connection maintained only by nexus seems to have a key role in cellular fragmentation. The addition of small concentrations of calcium, calcium channel blockers, and hyponatraemia hypothermia are important to prevent any cellular damage during reperfusion solutions with physiological concentration of calcium. PMID:25140476

  10. A Paradox of Newtonian Gravitation and Laplace's Solution

    Indian Academy of Sciences (India)

    2016-05-01

    Newton’s theory of gravitation solvedmany problemsof celestial mechanics but led to some majorproblems, one of which was that it gave rise toa serious paradox discussed in this article. Theparadox has a number of manifestations one ofwhich is presented here. It should be rememberedthat the root cause of all these paradoxes isfundamentally the same. Laplace attempted anad hoc solution. However, it could not be mathematicallydemonstrated that his proposal solvesthe difficulty. In this article, it is shown that hissuggestion removes the problem. A physical phenomenonthat can justify Laplace’s suggestion isalso mentioned briefly. This article also posesan interesting mathematical problem that can beattempted by interested readers. The computationalsolution is presented here.

  11. The obesity paradox in the ICU: real or not?

    Science.gov (United States)

    Dickerson, Roland N

    2013-06-12

    The obesity paradox has been used to describe the observed phenomenon described by several studies that indicated improved survival for critically ill patients with mild to moderate obesity when compared with their lean counterparts. The study by Arabi and coworkers challenges the obesity paradox concept for critically ill obese patients with septic shock. Their data indicate that obesity, per se, does not significantly improve mortality when outcomes are adjusted for differences in baseline characteristics and sepsis interventions. Further studies are needed to assess the influence of body weight, lean weight, and fat mass for optimizing fluid resuscitation, pharmacotherapy, and nutritional therapy for critically ill patients with sepsis.

  12. Testing the Transivity Explanation of the Allais Paradox

    DEFF Research Database (Denmark)

    Groes, Ebbe; Jacobsen, Hans Jørgen; Sloth, Birgitte;

    1999-01-01

    This paper uses a two-dimensional version of a standard common consequence experiment to test the intransitivity explanation of Allais-paradox-type violations of expected utility theory. We compare the common consequence effect of two choice problems differing only with respect to whether...... intransitivity as an explanation of the Allais Paradox. The question whether violations of expected utility are mainly due to intransitivity or to violation of independence is important since it is exactly on this issue the main new decision theories differ...

  13. Herbart paradoxal ? La lecture de Cassirer

    OpenAIRE

    Maigné, Carole

    2012-01-01

    Cet article voudrait éclaircir le paradoxe que Ernst Cassirer décèle chez Johann Friedrich Herbart, auquel il consacre un chapitre dense du volume 3 de son histoire de la philosophie : Le Problème de la connaissance. Il nous semble que le paradoxe se dénoue si Herbart est inscrit dans l’histoire même des écrits de Cassirer, depuis Substance et Fonction jusqu’à la Philosophie des formes symboliques : alors que Herbart s’inscrit pleinement dans cette ontologie fonctionnelle que décrit et promeu...

  14. Paradoxical intervention in the psychotherapeutic relationship as viewed from an ecosystemic perspective

    OpenAIRE

    2014-01-01

    M.A. (Clinical Psychology) This study traces the description of Paradox as a therapeutic measure by numerous therapists since Erikson first used the paradox in the form of positive reframing during the thirties. Major theoretical definitions of the paradoxical communication are reviewed. The therapeutic Paradoxical intervention is categorized into a series of relatively circumscribed intervention strategies, each of which shares theoretical similarities but emphasizes different aspects of ...

  15. The Inhabitance Paradox: how habitability and inhabitancy are inseparable

    Science.gov (United States)

    Goldblatt, C.

    2015-12-01

    The dominant paradigm in assigning "habitability" to terrestrial planets is to define a circumstellar habitable zone: the locus of orbital radii in which the planet is neither too hot nor too cold for life as we know it. One dimensional climate models have put theoretically impressive boundaries on this: a runaway greenhouse or water loss at the inner edge (Venus), and low-latitude glaciation followed by formation of CO2 clouds at the outer edge. A cottage industry now exists to "refine" the definition of these boundaries each year to the third decimal place of an AU. Using exactly that kind of model, I'll show that the different climate states can overlap very substantially and that "snowball Earth", temperate climate and a post-runaway climate can all be stable under the same solar flux. Furthermore, the radial extent of the temperature climate band is very narrow for pure water atmospheres. The width of the habitable zone is determined by the atmospheric inventories of di-nitrogen and carbon dioxide. Yet Earth teaches us that these abundances are very heavily influenced (perhaps even controlled) by biology. This is paradoxical: the habitable zone seeks to define the region a planet should be capable of harbouring life; yet whether the planet is inhabited will determine whether the climate may be habitable at any given distance from the star. This matters, because future life detection missions may use habitable zone boundaries in mission design. A historical view of solar system exploration helps frame the problem; robotic exploration of the outer solar system revealed the un-imagined nature of the Jovian and Saturnian moons, whilst showing that the Venusian jungle died long ago. Prediction will fall to data but the unexpected may emerge. To soften that fall we should revise the paradigm of habitability to acknowledge that habitability depends on inhabitance; for life as we know it is a planetary scale--and planet dominating--phenomenon.

  16. Case Study:The research of the paradox baradox between Strategic Alignment and IT Business Value

    Institute of Scientific and Technical Information of China (English)

    朱书阳

    2009-01-01

    This report analyses the case-Investigating the Relationship between Strategic Alignment and IT Business Value:The Discoven/of a Paradox,and interpret the paradox-step by step.First,the report introduces the stracegic alignment and IT business value.Then,the relationship betweenthem and the paradox is discussed.At last.conclusion and suggestion are made.

  17. Creative Paradoxical Thinking and Its Implications for Teaching and Learning Motor Skills

    Science.gov (United States)

    Chen, David

    2011-01-01

    A paradox is a statement or situation that involves two or more contradictory, mutually exclusive elements that operate at the same time. This article examines a number of findings in motor-learning and motor-control research and categorizes them into six paradoxes. Based on those research findings, the concept of creative paradoxical thinking is…

  18. Bifurcation of the roots of the characteristic polynomial and the destabilization paradox in friction induced oscillations

    Directory of Open Access Journals (Sweden)

    Kirillov O.N.

    2007-01-01

    Full Text Available Paradoxical effect of small dissipative and gyroscopic forces on the stability of a linear non-conservative system, which manifests itself through the unpredictable at first sight behavior of the critical non-conservative load, is studied. By means of the analysis of bifurcation of multiple roots of the characteristic polynomial of the non-conservative system, the analytical description of this phenomenon is obtained. As mechanical examples two systems possessing friction induced oscillations are considered: a mass sliding over a conveyor belt and a model of a disc brake describing the onset of squeal during the braking of a vehicle.

  19. Unilateral Carbon Taxation in the Global Economy: The Green Paradox and carbon leakage revisted

    OpenAIRE

    Frederick van der Ploeg

    2015-01-01

    Unilateral, second-best carbon taxes are analysed in a two-period, two-country model with international trade in final goods, oil and bonds. The increase in oil demand and acceleration of global warming resulting from a future carbon tax are large if the price elasticities of oil demand are large and that of oil supply is small, but are attenuated by the fall in the world interest rate especially if intertemporal substitution is weak. Despite this Green Paradox effect, green welfare rises if ...

  20. Obesity paradox in patients with community-acquired pneumonia: Is inflammation the missing link?

    Science.gov (United States)

    Braun, Nina; Hoess, Claus; Kutz, Alexander; Christ-Crain, Mirjam; Thomann, Robert; Henzen, Christoph; Zimmerli, Werner; Mueller, Beat; Schuetz, Philipp

    2017-01-01

    Positive associations between body mass index (BMI) and clinical outcomes have been found and are called "the obesity survival paradox." However, whether obesity has protective effects or if this paradox is because of confounding remains unclear. Herein, we analyzed the effects of weight on long-term mortality in a large cohort of patients with community-acquired pneumonia (CAP) and investigated whether the differential effects of obesity on inflammation pathways accounted for mortality differences. For this secondary analysis, we followed prospectively for 6 y 763 CAP patients who were previously included in a multicenter trial (the ProHOSP Trial). To assess associations of BMI with mortality and with several inflammatory biomarker levels, we calculated three regression models adjusted for severity: the pneumonia severity index (PSI); fully adjusted for PSI, age, sex, metabolic factors, cardiovascular diseases, and other comorbidities; and fully adjusted including biomarker levels. Within the 763 patients studied, all-cause 6-y mortality was significantly lower in obese patients (BMI >30 kg/m(2)) compared with normal-weight patients (BMI 18.5-25 kg/m(2)), with a severity-adjusted hazard ratio of 0.641 (95% confidence interval 0.462-0.889) and robust results in fully adjusted and fully adjusted plus biomarker models. No associations of increased BMI and C-reactive protein, procalcitonin, or white blood cell count were found, but BMI > 30 kg/m(2) was associated with higher proadrenomedullin levels. Over a 6-y long-term follow-up, we found obesity to be associated with lower all-cause mortality in CAP patients, confirming the obesity paradox in this population. However, differences in inflammatory pathways did not explain these findings. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Paradoxical anxiogenic response of juvenile mice to fluoxetine.

    Science.gov (United States)

    Oh, Ji-eun; Zupan, Bojana; Gross, Steven; Toth, Miklos

    2009-09-01

    Depression, anxiety, and conduct disorders are common in children and adolescents, and selective serotonin reuptake inhibitors (SSRIs) are often used to treat these conditions. Fluoxetine (Prozac) is the first approved SSRI for the treatment of depression in this population. Although it is believed that overall, fluoxetine is effective in child and adolescent psychiatry, there have been reports of specific adverse drug effects, most prominently, suicidality and psychiatric symptoms such as agitation, worsening of depression, and anxiety. Chronic fluoxetine substantially increases brain extracellular 5-HT concentrations, and the juvenile developing brain may respond to supraphysiological 5-HT levels with specific adverse effects not seen or less prominent in adult brain. Using novelty-induced hypophagia, as well as open-field and elevated plus maze tests, we show that both Swiss Webster and C57Bl/6 mice, receiving fluoxetine in a clinically relevant dose and during their juvenile age corresponding to child-adolescent periods in humans, exhibit a paradoxical anxiogenic response. The adverse effects of juvenile fluoxetine disappeared upon drug discontinuation and no long-term behavioral consequences were apparent. No adverse effect to chronic fluoxetine was seen in adult mice and a dose-dependent anxiolytic effect developed. These data show that the age of the mice, independently of the strains and tests used in this study, is the determining factor of whether the response to chronic fluoxetine is anxiolytic or anxiogenic. Taken together, the response of the juvenile and adult brain to fluoxetine could be fundamentally different and the juvenile fluoxetine administration mouse model described here may help to identify the mechanism underlying this difference.

  2. Paradoxical facilitation of working memory after basolateral amygdala damage.

    Directory of Open Access Journals (Sweden)

    Barak Morgan

    Full Text Available Working memory is a vital cognitive capacity without which meaningful thinking and logical reasoning would be impossible. Working memory is integrally dependent upon prefrontal cortex and it has been suggested that voluntary control of working memory, enabling sustained emotion inhibition, was the crucial step in the evolution of modern humans. Consistent with this, recent fMRI studies suggest that working memory performance depends upon the capacity of prefrontal cortex to suppress bottom-up amygdala signals during emotional arousal. However fMRI is not well-suited to definitively resolve questions of causality. Moreover, the amygdala is neither structurally or functionally homogenous and fMRI studies do not resolve which amygdala sub-regions interfere with working memory. Lesion studies on the other hand can contribute unique causal evidence on aspects of brain-behaviour phenomena fMRI cannot "see". To address these questions we investigated working memory performance in three adult female subjects with bilateral basolateral amygdala calcification consequent to Urbach-Wiethe Disease and ten healthy controls. Amygdala lesion extent and functionality was determined by structural and functional MRI methods. Working memory performance was assessed using the Wechsler Adult Intelligence Scale-III digit span forward task. State and trait anxiety measures to control for possible emotional differences between patient and control groups were administered. Structural MRI showed bilateral selective basolateral amygdala damage in the three Urbach-Wiethe Disease subjects and fMRI confirmed intact functionality in the remaining amygdala sub-regions. The three Urbach-Wiethe Disease subjects showed significant working memory facilitation relative to controls. Control measures showed no group anxiety differences. Results are provisionally interpreted in terms of a 'cooperation through competition' networks model that may account for the observed paradoxical

  3. The Pink Elephant Paradox (or, Avoiding the Misattribution of Data

    Directory of Open Access Journals (Sweden)

    Jude A. Spiers

    2002-12-01

    Full Text Available The pink elephant paradox refers to the threat to inductive thinking caused by the difficulty of inadvertently proving the existence of a concept or phenomena just because it overtly or insidiously exists in one's thoughts, leading to misattribution, or miscategorization of data, and thus subverting inductive processes. As Morse and Mitcham discussed in Part I, this is reduced through inductive strategies, including processes of saturation, replication, and verification. In this article, I present a story of how the phenomenon of interest in nurse-patient interaction evolved and emerged through a number of qualitative projects. At each stage, concepts were identified, explored, and developed in order to more elucidate the central phenomenon. I will show how, while at times I could identify and avoid the pink elephant, at other times there were one or a herd lurking in the shadows or rampaging through my work. I think that discussing both the successes and pit falls is one way to acknowledge and address the fact that, although we accept the evolution in ideas and thought processes in qualitative research, we still may not be comfortable in articulating the far more complex and insidious threats to inductive processes. Some schools of qualitative inquiry consider analysis of the literature a hindrance—in fact an invalidity—before commencing fieldwork. To the contrary, when a researcher is studying a concept rather than letting a concept emerge from a setting, it is essential to undertake a thorough theoretical and conceptual analysis of the literature (Morse, 2000; Morse et al, 1996. In my own program of research, the concept analysis was a study in, and of, itself, with the purpose of examining the maturity of concepts, and the explicit and implicit theoretical and research models. The literature constituted data that could be analyzed and formed the basis for a reconceptualization of the original concept by contrasting it with the theory

  4. Localization of the brainstem GABAergic neurons controlling paradoxical (REM sleep.

    Directory of Open Access Journals (Sweden)

    Emilie Sapin

    Full Text Available Paradoxical sleep (PS is a state characterized by cortical activation, rapid eye movements and muscle atonia. Fifty years after its discovery, the neuronal network responsible for the genesis of PS has been only partially identified. We recently proposed that GABAergic neurons would have a pivotal role in that network. To localize these GABAergic neurons, we combined immunohistochemical detection of Fos with non-radioactive in situ hybridization of GAD67 mRNA (GABA synthesis enzyme in control rats, rats deprived of PS for 72 h and rats allowed to recover after such deprivation. Here we show that GABAergic neurons gating PS (PS-off neurons are principally located in the ventrolateral periaqueductal gray (vlPAG and the dorsal part of the deep mesencephalic reticular nucleus immediately ventral to it (dDpMe. Furthermore, iontophoretic application of muscimol for 20 min in this area in head-restrained rats induced a strong and significant increase in PS quantities compared to saline. In addition, we found a large number of GABAergic PS-on neurons in the vlPAG/dDPMe region and the medullary reticular nuclei known to generate muscle atonia during PS. Finally, we showed that PS-on neurons triggering PS localized in the SLD are not GABAergic. Altogether, our results indicate that multiple populations of PS-on GABAergic neurons are distributed in the brainstem while only one population of PS-off GABAergic neurons localized in the vlPAG/dDpMe region exist. From these results, we propose a revised model for PS control in which GABAergic PS-on and PS-off neurons localized in the vlPAG/dDPMe region play leading roles.

  5. A paradoxical harmony in Jeremiah 20:7-18

    African Journals Online (AJOL)

    exercise with a therapeutic effect (with varying degrees of success). In the book of ... artificial generation of optimism can be short-lived and lead to depression. The .... As in the case of Job, this co-existence of defiance and acceptance, praise ... burning paradox of categorical commitment to Jahweh in spite of apparent self-.

  6. Underlying Paradox in the European Union's Multilingualism Policies

    Science.gov (United States)

    Johnson, Fern L.

    2013-01-01

    The European Union (EU) has developed comprehensive policies in recent years to promote multilingualism. In this article, major EU policy statements on multilingualism are analyzed to demonstrate how their underlying language ideology produces paradox by both encouraging multilingualism and regulating its definition within the EU. The first…

  7. Linearization of Schwarzschild's line element - Application to the clock paradox.

    Science.gov (United States)

    Broucke, R.

    1971-01-01

    This article studies the relativistic theory of the motion of a particle in the presence of a uniform acceleration field. The problem is introduced as a linearization of the fundamental line element of general relativity. The linearized line element is a solution of Einstein's field equations. The equations of geodesics corresponding to this line element are solved and applied to the clock paradox problem.-

  8. Managing Polarity, Paradox, and Dilemma during Leader Transition

    Science.gov (United States)

    Manderscheid, Steven V.; Freeman, Peter D.

    2012-01-01

    Purpose: The purpose of this study is to review literature relevant to leader transition and the navigation of polarities, paradoxes, and dilemmas that exist in organizations. Furthermore, the researchers aim to critique the literature and provide suggestions for practitioners and researchers interested in leader transition through the lens of…

  9. Service Recovery Paradox In Indian Banking Industry: An Empirical Investigation

    Directory of Open Access Journals (Sweden)

    Arunesh Garg

    2013-10-01

    Full Text Available The present study examines existence of service recovery paradox in Indian banking industry. The study is taken up in the tri-city of Chandigarh, Panchkula and Mohali. The respondents are catego- rized into failure and no-failure groups on the basis of their service experience. Failure group consti- tutes those respondents who have experienced service recovery, and has been further divided into five sub-groups ranging from service recovery++ (service recovery better than expected to service recovery- - (service recovery worse than expected. Service recovery paradox is examined by com- paring service recovery++ group with no-failure group. The study shows evidence for existence of service recovery paradox in relation to satisfaction. It has been concluded that for service recovery paradox to exist, recovery effort has to be exceptionally good and much better than expectation level of the customer. The study suggests that service managers should take service failure as an opportunity to appease customers by providing a much better than expected recovery experience. However, organizations should not plan to create service failure situations because if they falter on imparting the recovery, customer satisfaction may be influenced negatively.

  10. Understanding Persistent Food Insecurity: A Paradox of Place and Circumstance

    Science.gov (United States)

    Mammen, Sheila; Bauer, Jean W.; Richards, Leslie

    2009-01-01

    Survey data from a U.S. Department of Agriculture funded multi-state longitudinal project revealed a paradox where rural low-income families from states considered prosperous were persistently more food insecure than similar families from less prosperous states. An examination of quantitative and qualitative data found that families in the food…

  11. Cell size and cancer: a new solution to Peto's paradox?

    Science.gov (United States)

    Maciak, Sebastian; Michalak, Pawel

    2015-01-01

    Cancer, one of the leading health concerns for humans, is by no means a human-unique malady. Accumulating evidence shows that cancer kills domestic and wild animals at a similar rate to humans and can even pose a conservation threat to certain species. Assuming that each physiologically active and proliferating cell is at risk of malignant transformation, any evolutionary increase in the number of cells (and thus body mass) will lead to a higher cancer frequency, all else being equal. However, available data fail to support the prediction that bigger animals are affected by cancer more than smaller ones. The unexpected lack of correlation between body size (and life span) and cancer risk across taxa was dubbed Peto's paradox. In this perspective, several plausible explanations of Peto's paradox are presented, with the emphasis on a largely underappreciated relation of cell size to both metabolism and cell division rates across species, which we believe are key factors underlying the paradox. We conclude that larger organisms have bigger and slowly dividing cells with lower energy turnover, all significantly reducing the risk of cancer initiation. Solving Peto's paradox will enhance our understanding the evolution of cancer and may provide new implications for cancer prevention and treatment.

  12. An Apparent Paradox: Catt's Anomaly

    Science.gov (United States)

    Pieraccini, M.; Selleri, S.

    2013-01-01

    Catt's anomaly is a sort of "thought experiment" (a "gedankenexperiment") where electrons seem to travel at the speed of light. Although its author argued with conviction for many years, it has a clear and satisfactory solution and it can be considered indubitably just an apparent paradox. Nevertheless, it is curious and…

  13. Underlying Paradox in the European Union's Multilingualism Policies

    Science.gov (United States)

    Johnson, Fern L.

    2013-01-01

    The European Union (EU) has developed comprehensive policies in recent years to promote multilingualism. In this article, major EU policy statements on multilingualism are analyzed to demonstrate how their underlying language ideology produces paradox by both encouraging multilingualism and regulating its definition within the EU. The first…

  14. Simpson's Paradox in the Interpretation of "Leaky Pipeline" Data

    Science.gov (United States)

    Walton, Paul H.; Walton, Daniel J.

    2016-01-01

    The traditional "leaky pipeline" plots are widely used to inform gender equality policy and practice. Herein, we demonstrate how a statistical phenomenon known as Simpson's paradox can obscure trends in gender "leaky pipeline" plots. Our approach has been to use Excel spreadsheets to generate hypothetical "leaky…

  15. On the Measurement Problem and the EPR Paradox

    OpenAIRE

    Muchowski, Eugen

    2016-01-01

    After a polarization measurement with photons in singlet state we know for certain the photons were in the measured state prior to measurement. Photons in singlet state do therefore not exhibit action at a distance. The EPR paradox with entangled photons has been challenged. It was also shown why quantum mechanics infringes Bells inequality.

  16. Working-life - A paradox in Knowledge-Intensive Companies

    DEFF Research Database (Denmark)

    Ipsen, Christine

    2004-01-01

    A Working-Life Paradox in Knowledge Intensive Companies Keywords: Knowledge work, knowledge management, working-life, consulting companies. The purpose of this article is to identify the influence knowledge-work has on working life of the personnel in knowledge-intensive companies, more precisely...

  17. Effects of Paradoxical and Self-Control Directives in Counseling.

    Science.gov (United States)

    Lopez, Frederick G.; Wambach, Cathrine A.

    1982-01-01

    Subjects (N=32) with recurring procrastination problems were assigned to either of two directive interview conditions (paradoxical or self-control) or to a no-interview control condition. Results indicated both directive groups exhibited generally greater improvement over time than controls and that opposing forms of direction promoted different…

  18. Paradox of the Characters in The Picture of Dorian Gray

    Institute of Scientific and Technical Information of China (English)

    张东博

    2014-01-01

    Oscar Wilde is a brilliant Irish dramatist, novelist and critic. His only novel - The Picture of Dorian Gray- is one of the most influential works by Wilde. This paper aims to study the paradox of the three main characters’ life in this novel through close reading in order to achieve a better understanding of this controversial book.

  19. Keeping Public Officials Accountable through Dialogue: Resolving the Accountability Paradox.

    Science.gov (United States)

    Roberts, Nancy C.

    2002-01-01

    Discusses Harmon's Accountability Paradox in relation to the accountability of public officials. Promotes the use of dialogue because its advantage outweighs its cost as a mechanism of accountability when officials confront problems that defy definition and solution and when traditional solution methods have failed. (Contains 54 references.) (JOW)

  20. Anatomy of the obesity paradox in heart failure.

    Science.gov (United States)

    Guglin, Maya; Baxi, Khyati; Schabath, Mathew

    2014-09-01

    A counterintuitive phenomenon of survival advantage in obese patients with heart failure (HF) is called obesity paradox. In this review, we emphasize that in nearly all research papers on this subject, there were marked differences between the groups with different body mass index (BMI). Surprisingly, these differences are very consistent and mostly in favor of patients with higher BMI. Obese individuals in HF studies almost invariably were characterized by much younger age, better nutritional status, higher blood pressure, less arrhythmia, less anemia, less valvular regurgitation, better left ventricular systolic function, better lungs, and better renal function. There is no paradox in their better survival. None of the studies confirming the obesity paradox were designed as prospective studies with the purpose to find the effects of BMI on survival. All the studies represent post hoc analysis of clinical trials designed for different purposes, or retrospective studies, or analysis of registries. Multiple baseline differences of subgroups with different BMI likely contribute to the obesity paradox, because not all variables influencing the outcomes can be accounted for.

  1. Apparent Paradoxes in Classical Electrodynamics: Relativistic Transformation of Force

    Science.gov (United States)

    Kholmetskii, A. L.; Yarman, T.

    2007-01-01

    In this paper, we analyse a number of paradoxical teaching problems of classical electrodynamics, dealing with the relativistic transformation of force for complex macro systems, consisting of a number of subsystems with nonzero relative velocities such as electric circuits that change their shape in the course of time. (Contains 7 figures.)

  2. Working-life - A paradox in Knowledge-Intensive Companies

    DEFF Research Database (Denmark)

    Ipsen, Christine

    2004-01-01

    A Working-Life Paradox in Knowledge Intensive Companies Keywords: Knowledge work, knowledge management, working-life, consulting companies. The purpose of this article is to identify the influence knowledge-work has on working life of the personnel in knowledge-intensive companies, more precisely...

  3. On the mechanics of the arrow : Archer's paradox

    NARCIS (Netherlands)

    Kooi, BW; Sparenberg, JA

    1997-01-01

    In ancient bows the grip of the bow was in the way of the arrow. The arrow needed to get round the bow while being accelerated; this phenomenon is called the 'Archer's Paradox'. In the forties it was observed experimentally with high-speed cameras that the arrow vibrates in a horizontal plane perpen

  4. The happiness paradox: your friends are happier than you

    NARCIS (Netherlands)

    Bollen, J.; Leemput, van de I.A.; Goncalves Souza, M.B.; Ruan, G.

    2016-01-01

    Most individuals in social networks experience a so-called Friendship Paradox: they are less popular than their friends on average. This effect may explain recent findings that widespread social network media use leads to reduced happiness. However the relation between popularity and happiness is po

  5. Braess like Paradox in a Small World Network

    CERN Document Server

    Toyota, Norihito

    2013-01-01

    Braess \\cite{1} has been studied about a traffic flow on a diamond type network and found that introducing new edges to the networks always does not achieve the efficiency. Some researchers studied the Braess' paradox in similar type networks by introducing various types of cost functions. But whether such paradox occurs or not is not scarcely studied in complex networks. In this article, I analytically and numerically study whether Braess like paradox occurs or not on Dorogovtsev-Mendes network\\cite{2}, which is a sort of small world networks. The cost function needed to go along an edge is postulated to be equally identified with the length between two nodes, independently of an amount of traffic on the edge. It is also assumed the it takes a certain cost $c$ to pass through the center node in Dorogovtsev-Mendes network. If $c$ is small, then bypasses have the function to provide short cuts. As result of numerical and theoretical analyses, while I find that any Braess' like paradox will not occur when the n...

  6. Perspectives and Paradoxes in the sensory-cultural explorative approach

    DEFF Research Database (Denmark)

    Lundberg, Pia

    of oppression, injustice and defiance/insubordination. In a fieldwork in Sierra Leone, West Africa, where I was exploring the paradoxes between the powerful display of the proud and esoteric narrative of the knowledge residing in "the secret societies of women" and the contrast to the everyday stories...... of poverty....

  7. The Power of Paradox in Learning to Teach

    Science.gov (United States)

    Noordhoff, Karen

    2012-01-01

    This chapter makes the case for engaging teacher candidates with matters of personal identity and integrity, using explorations of the paradox of self and role, in teacher education programs dominated by a focus on professional knowledge and skills, based on the analysis of interviews with novice teachers. The author argues that both teacher…

  8. An Apparent Paradox: Catt's Anomaly

    Science.gov (United States)

    Pieraccini, M.; Selleri, S.

    2013-01-01

    Catt's anomaly is a sort of "thought experiment" (a "gedankenexperiment") where electrons seem to travel at the speed of light. Although its author argued with conviction for many years, it has a clear and satisfactory solution and it can be considered indubitably just an apparent paradox. Nevertheless, it is curious and…

  9. Sense or Sensibility——The Paradoxical Forces on Man

    Institute of Scientific and Technical Information of China (English)

    周芹

    2009-01-01

    Based on the analysis of the two central characters in Two Fishermen,in this paper,it presents sense and sensibility which ale conveyed by the characters in the short story and the significance of the paradoxical forces of sense and sensibility in reality.

  10. The Punitive Paradox: Desert and the Compulsion to Punish.

    Science.gov (United States)

    Clear, Todd R.

    1996-01-01

    Explores the concept of a "just deserts" justice paradox in which carrying out a deserved penalty breaches the values that undergird the theory of just deserts. Examines whether it might ever be proper, from a desert perspective, to choose not to impose a deserved punishment. (KW)

  11. A Powerful Theory and a Paradox: Ecological Psychologists after Barker

    Science.gov (United States)

    Scott, M. M.

    2005-01-01

    Roger Barker, influenced by Lewin, developed a powerful theory in psychology, behavior setting theory. Paradoxically, this theory is still not widely known or understood in mainstream American psychology. Oral histories of the core group who worked with Barker were collected and examined to determine influences on them and subsequent directions in…

  12. A Paradoxical Academic Identity: Fate, Utopia and Critical Hope

    Science.gov (United States)

    Sutton, Paul

    2015-01-01

    Using a dialectical mode of exposition, I offer a reflexive sociological theorisation of the paradox that characterises my academic identity: a fatalistic disenchantment concerning the colonisation of Higher Education (HE) by neoliberalism co-exists with a utopianism concerning HE's emancipatory possibilities. I begin with a discussion of Weber's…

  13. Globalization and Religion in Historical Perspective: A Paradoxical Relationship

    Directory of Open Access Journals (Sweden)

    Luke M. Herrington

    2013-03-01

    Full Text Available Religion has long been a driving force in the process of globalization. This idea is not controversial or novel thinking, nor is it meant to be. However, the dominant reasoning on the subject of globalization, expressed by authors like Thomas Friedman, places economics at the center of analysis, skewing focus from the ideational factors at work in this process. By expanding the definition of globalization to accommodate ideational factors and cultural exchange, religion’s agency in the process can be enabled. Interestingly, the story of religion and globalization is in some ways the history of globalization, but it is riddled with paradoxes, including the agent-opponent paradox, the subject of this article. Religion and globalization have a co-constitutive relationship, but religious actors are both agents of globalization and principals in its backlash. While some actors might benefit from a mutually reinforcing relationship with globalization, others are marginalized in some way or another, so it is necessary to expose the links and wedges that allow for such a paradox. To that end, the concepts of globalization and religious actors must be defined, and the history of the agent-opponent paradox, from the Buddhists of the Silk Road to the Jubilee campaign of 2000, must be elucidated.

  14. Paradox of Our Times: Hunger in a Strong Economy.

    Science.gov (United States)

    Venner, Sandra H.; Sullivan, Ashley F.; Seavey, Dorie

    America today is haunted by the paradox of hunger and food insecurity amidst unprecedented prosperity. Despite a record economic expansion, millions of American households struggle to find sufficient resources to feed family members. Focusing on families with children, this report presents current evidence on hunger and food insecurity, identifies…

  15. The Paradox of Reducing Class Size and Improving Learning Outcomes

    Science.gov (United States)

    Hattie, John

    2005-01-01

    This paper addresses four questions: What are the effects of reducing class size? How important are these effects? How can we explain these effects? and How can we improve the outcomes when class sizes are reduced? A major aim is to provide directions for resolving the paradox as to "Why reducing class size has not led to major improvements in…

  16. A Possible Explanation to Paradox in Horse Spleen Ferritins

    Institute of Scientific and Technical Information of China (English)

    寇谡鹏; 梁九卿

    2003-01-01

    There are contradicting opinions about the tunnelling experiments in horse-spleen ferritin particles. By distinguish the coherent and incoherent tunnelling processes, we give a unified explanation to different experiments. As a result, a possible explanation to the paradox is proposed

  17. Time symmetry and interpretation of quantum mechanics. [Paradoxes

    Energy Technology Data Exchange (ETDEWEB)

    de Beauregard, O.C.

    1976-10-01

    A drastic resolution of the quantum paradoxes is proposed, combining (I) von Neumann's postulate that collapse of the state vector is due to the act of observation, and (II) my reinterpretation of von Neumann's quantal irreversibility as an equivalence between wave retardation and entropy increase, both being ''factlike'' rather than ''lawlike'' (Mehlberg). This entails a coupling of the two de jure symmetries between (I) retarded and (II) advanced waves, and between Aristotle's information as (I) learning and (II) willing awareness. Symmetric acceptance of cognizance as a source of retarded waves, and of will as a sink of advanced waves, is submitted as a central ''paradox'' of the Copernican or Einsteinian sort, out of which new light is shed upon previously known paradoxes, such as the EPR paradox, Schroedinger's cat, and Wigner's friend. Parapsychology is thus found to creep into the picture.

  18. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun [Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Lee, Hyong Woo; Chung, Jin Hong [Yeongnam National University College of Medicine, Daegu (Korea, Republic of)

    1990-07-15

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  19. Deeper Subduction Zone Melting Explains Enrichment of Upper Mantle and Resolves Dehydration Paradox

    Science.gov (United States)

    Dixon, Jacqueline; Bindeman, Ilya; Kingsley, Richard

    2017-04-01

    We present new volatile and stable isotope data on oceanic basaltic glasses with a range of enriched compositions. Basalt compositions studied here can be modeled by mixing between depleted mantle and various enriched (EM) and prevalent (PREMA) mantle components. We develop a multi-stage metasomatic and melting model for the origin of the enriched components, extending the subduction factory concept to involve melting of different components at different depths, down to the mantle transition zone (660 km), with slab temperature a key variable. EM components are heterogeneous, ranging from wet and heavy (Arctic Ridges) to dry and light (East Pacific Rise), and are derived from the subducted slab at depths of 150 to 250 km by addition of paradox," refering to the following conundrum. The enriched "prevalent mantle" (PREMA) end-member in mid-oceanic ridge and ocean island basalts requires involvement of a mostly dehydrated slab component to explain trace element ratios and radiogenic isotopic compositions, but a fully hydrated slab component to explain stable isotope compositions. In our model, thermal parameters of slabs control the timing and composition of subduction-derived components. This includes deep release of fluids from subcrustal hydrous phases that may rehydrate previously dehydrated slab, resolving the paradox.

  20. The stability of ecosystems: A brief overview of the paradox of enrichment

    Indian Academy of Sciences (India)

    Shovonlal Roy; J Chattopadhyay

    2007-03-01

    In theory, enrichment of resource in a predator–prey model leads to desta bilization of the system, thereby collapsing the trophic interaction, a phe nomenon referred to as ``the paradox of enrichment”. After it was first pro posed by Rosenzweig (1971), a number of subsequent studies were carried out on this dilemma over many decades. In this article, we review these the oretical and experimental works and give a brief overview of the proposed solutions to the paradox. The mechanisms that have been discussed are modifications of simple predator–prey models in the presence of prey that is inedible, invulnerable, unpalatable and toxic. Another class of mechanisms includes an incorporation of a ratio-dependent functional form, inducible defence of prey and density-dependent mortality of the predator. Moreover, we find a third set of explanations based on complex population dynamics including chaos in space and time. We conclude that, although any one of the various mechanisms proposed so far might potentially prevent destabilization of the predator–prey dynamics following enrichment, in nature different mechanisms may combine to cause stability, even when a system is enriched. The exact mechanisms, which may differ among systems, need to be disentangled through extensive field studies and labo ratory experiments coupled with realistic theoretical models.

  1. Obesity paradox in group 1 pulmonary hypertension: analysis of the NIH-Pulmonary Hypertension registry.

    Science.gov (United States)

    Mazimba, S; Holland, E; Nagarajan, V; Mihalek, A D; Kennedy, J L W; Bilchick, K C

    2017-08-01

    The 'obesity paradox' refers to the fact that obese patients have better outcomes than normal weight patients. This has been observed in multiple cardiovascular conditions, but evidence for obesity paradox in pulmonary hypertension (PH) remains sparse. We categorized 267 patients from the National Institute of Health-PH registry into five groups based on body mass index (BMI): underweight, normal weight, overweight, obese and morbidly obese. Mortality was compared in BMI groups using the χ(2) statistic. Five-year probability of death using the PH connection (PHC) risk equation was calculated, and the model was compared with BMI groups using Cox proportional hazards regression and Kaplan-Meier (KM) survival curves. Patients had a median age of 39 years (interquartile range 30-50 years), a median BMI of 23.4 kg m(-)(2) (21.0-26.8 kg m(-2)) and an overall mortality at 5 years of 50.2%. We found a U-shaped relationship between survival and 1-year mortality with the best 1-year survival in overweight patients. KM curves showed the best survival in the overweight, followed by obese and morbidly obese patients, and the worst survival in normal weight and underweight patients (log-rank P=0.0008). In a Cox proportional hazards analysis, increasing BMI was a highly significant predictor of improved survival even after adjustment for the PHC risk equation with a hazard ratio for death of 0.921 per kg m(-2) (95% confidence interval: 0.886-0.954) (Pparadox' than an 'obesity paradox'. This has implications for risk stratification and prognosis in group 1 PH patients.

  2. Classical interaction of a magnet and a point charge: The Shockley-James paradox

    Science.gov (United States)

    Boyer, Timothy H.

    2015-01-01

    It is pointed out that the interaction of a magnet and a point charge has not been properly understood because the mutual interactions of the magnet's current carriers have been neglected. The magnet-point-charge interaction is important for understanding some theoretical paradoxes, such as the Shockley-James paradox, and for interpreting some experimentally observed effects, such as the Aharonov-Bohm and Aharonov-Casher phase shifts. Coleman and Van Vleck provide a discussion of the Shockley-James paradox where they note that internal relativistic mechanical momentum (hidden momentum) can be carried by the current carriers of the magnet. Although internal mechanical momentum is indeed dominant for noninteracting particles moving in a closed orbit under the influence of an external electric field, the presence of interactions among the magnet's current carriers leads to an internal electromagnetic momentum, which does not seem to be recognized in the physics literature. In the interacting multiparticle situation, the external charge induces an electrostatic polarization of the magnet, which leads to an internal electromagnetic momentum in the magnet where both the electric and magnetic fields for the momentum are contributed by the magnet particles. This internal electromagnetic momentum for the interacting multiparticle situation is equal in magnitude and opposite in direction compared to the familiar external electromagnetic momentum where the electric field is contributed by the external charged particle and the magnetic field is that due to the magnet. In the present article, the momentum balance of the Shockley-James situation for a system of a magnet and a point charge is calculated in detail for a magnet model consisting of two interacting point charges, which are constrained to move in a circular orbit on a frictionless ring with a compensating negative charge at the center.

  3. Role of innate immune receptors in paradoxical caspofungin activity in vivo in preclinical aspergillosis.

    Science.gov (United States)

    Moretti, Silvia; Bozza, Silvia; D'Angelo, Carmen; Casagrande, Andrea; Della Fazia, Maria Agnese; Pitzurra, Lucia; Romani, Luigina; Aversa, Franco

    2012-08-01

    This study investigated the possible mechanisms underlying the paradoxical caspofungin activity in vivo in preclinical aspergillosis. We evaluated the activity of escalating doses of caspofungin in vivo in different preclinical models of invasive aspergillosis, including mice deficient for selected innate immune receptors. The therapeutic efficacy of caspofungin in experimental invasive aspergillosis was strictly dose dependent, being observed at doses of 0.1 and 1 mg/kg of body weight depending on the experimental models. Paradoxical increase in pulmonary fungal burden as well as inflammatory pathology was observed at the highest dose of caspofungin (5 mg/kg), occurred independently of the so-called Eagle effect and susceptibility to caspofungin in vitro, and was contingent upon the presence of TLR2, Dectin-1, and TLR9. Increased expression of Dectin-1 and TLR9 were observed upon exposure to caspofungin in vitro and in vivo. Together, these findings suggest that the net activity of caspofungin in vivo is orchestrated by the activation, directly or indirectly, of multiple innate immune receptors.

  4. The paradox of soft singularity crossing and its resolution by distributional cosmological quantitities

    CERN Document Server

    Keresztes, Zoltán; Kamenshchik, Alexander Yu

    2012-01-01

    A cosmological model of a flat Friedmann universe filled with a mixture of anti-Chaplygin gas and dust-like matter exhibits a future soft singularity, where the pressure of the anti-Chaplygin gas diverges (while its energy density vanishes). Despite infinite tidal forces the geodesics pass through the singularity. Due to the dust component, the Hubble parameter has a non-zero value at the encounter with the singularity, therefore the dust implies further expansion. With continued expansion however, the energy density and the pressure of the anti-Chaplygin gas would become ill-defined, hence from the point of view of the anti-Chaplygin gas only a contraction is allowed. Paradoxically, the universe in this cosmological model would have to expand and contract simultaneously. This obviosly could not happen. We solve the paradox by redefining the anti-Chaplygin gas in a distributional sense. Then a contraction could follow the expansion phase at the singularity at the price of a jump in the Hubble parameter. Altho...

  5. Paradox of soft singularity crossing and its resolution by distributional cosmological quantities

    Science.gov (United States)

    Keresztes, Zoltán; Gergely, László Á.; Kamenshchik, Alexander Yu.

    2012-09-01

    A cosmological model of a flat Friedmann universe filled with a mixture of anti-Chaplygin gas and dustlike matter exhibits a future soft singularity, where the pressure of the anti-Chaplygin gas diverges (while its energy density is finite). Despite infinite tidal forces the geodesics pass through the singularity. Because of the dust component, the Hubble parameter has a nonzero value at the encounter with the singularity, therefore the dust implies further expansion. With continued expansion however, the energy density and the pressure of the anti-Chaplygin gas would become ill-defined hence from the point of view of the anti-Chaplygin gas only a contraction is allowed. Paradoxically, the universe in this cosmological model would have to expand and contract simultaneously. This obviously could not happen. We solve the paradox by redefining the anti-Chaplygin gas in a distributional sense. Then a contraction could follow the expansion phase at the singularity at the price of a jump in the Hubble parameter. Although such an abrupt change is not common in any cosmological evolution, we explicitly show that the set of Friedmann, Raychaudhuri and continuity equations are all obeyed both at the singularity and in its vicinity. We also prove that the Israel junction conditions are obeyed through the singular spatial hypersurface. In particular we enounce and prove a more general form of the Lanczos equation.

  6. Altruism, Noise, and the Paradox of Voter Turnout: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Sarah A. Tulman

    2015-01-01

    Full Text Available This paper addresses the paradox of voter turnout, wherein observed voting participation rates are far greater than what rational choice theory would predict. Voters face multiple voting choices, stochastic voting costs, and candidates offering different economic platforms. A combination of two approaches attempts to resolve this paradox: quantal response equilibrium (QRE analysis, which introduces noise into the decision-making process, and the possibility of ethical (altruism-motivated voting. A series of laboratory experiments empirically tests the predictions of the resulting model. Participants in the experiments are also given opportunities for communicating online with their immediate neighbors, in order to enhance the chances that subjects would realize the possibility of ethical voting. The results show that ethical voting occurs but gains momentum only in the presence of a vocal advocate and even then it mostly dissipated by the second half of the session. The QRE-based model was able to explain some but not all of the overvoting that was observed, relative to the Nash equilibrium prediction. There is evidence to suggest that communication via the chat feature generated some of the voting and also some of the ethical voting.

  7. Basing on the Cournot Model to Explore Smith Paradox%基于古诺模型的斯密悖论探究——兼评心理主义与反心理主义

    Institute of Scientific and Technical Information of China (English)

    温旭

    2011-01-01

    "斯密悖论"指斯密在《国富论》中以利己心为核心的经济人和《道德情操论》中以同情心为核心的道德人之间的矛盾。一个半世纪以来,国内外学界围绕着这一"悖论"的研究持续不断。借助古诺模型的方法对"斯密悖论"中的经济人与道德人进行博弈分析,试图提出利己与利他的有机统一体——经济道德人。%"Smith paradox" means the contradiction between economic man who with the economic benefit as the core in The Wealth of Nations and moral man who with the sympathy as the core in The Theory of Moral Sentiments.One and a half century,scholars both at home and abroad continue to research this "paradox".This paper based on the Cournot model metho to analysis the game between the economic man and the moral man in "Smith paradox",and tries to put forward ego and altruism organic unity-economic moral man.

  8. [The role of paradoxical sleep in learning in man].

    Science.gov (United States)

    Fanjaud, G; Calvet, U; Rous de Feneyrols, A; Barrere, M; Bes, A; Arbus, L

    1982-12-01

    The authors have tried to specify the role of paradoxical sleep (PS) in the learning process in man. For their study they used 12 medical students. Three polygraphic recordings of sleep were performed over 3 consecutive days. The night of the third day was preceded by the learning test (a series of 4 tests). A simultaneous study was carried out of the effects of learning on sleep and vice versa. This study does not show any significant increase in the total time of paradoxical sleep during the night which followed the learning. Only the second period of PS was increased. Thus, this research does not seem to confirm the results obtained in animals. But this disagreement may be explained by the limited number of subjects or by the contents of the tests used. On the other hand, the authors did obtain results which seem to confirm the favourable influence of sleep as a whole on the learning process.

  9. The twin paradox with macroscopic clocks in superconducting circuits

    CERN Document Server

    Lindkvist, Joel; Fuentes, Ivette; Dragan, Andrzej; Svensson, Ida-Maria; Delsing, Per; Johansson, Göran

    2014-01-01

    Time dilation, a striking prediction of Einstein's relativity, plays an important role in applications such as the Global Positioning System. One of the most compelling consequences of time dilation is known as the twin paradox, where a twin at rest ages more than her sibling travelling at relativistic speeds. In this paper, we propose an implementation of the twin paradox in superconducting circuits with velocities as large as a few percent of the speed of light. Ultrafast modulation of the boundary conditions for the electromagnetic field in a microwave cavity simulates a clock moving at relativistic speeds. While previous demonstrations of this effect involve point-like clocks, our superconducting cavity has a finite length, allowing us to investigate the role of clock size as well as interesting quantum effects on time dilation. In particular, our theoretical results show that the travelling twin ages slower for larger cavity lengths and that quantum particle creation, known in this context as the dynamic...

  10. A computational approach to the twin paradox in curved spacetime

    CERN Document Server

    Fung, Kenneth K H; Lewis, Geraint F; Wu, Xiaofeng

    2016-01-01

    Despite being a major component in the teaching of special relativity, the twin `paradox' is generally not examined in courses on general relativity. Due to the complexity of analytical solutions to the problem, the paradox is often neglected entirely, and students are left with an incomplete understanding of the relativistic behaviour of time. This article outlines a project, undertaken by undergraduate physics students at the University of Sydney, in which a novel computational method was derived in order to predict the time experienced by a twin following a number of paths between two given spacetime coordinates. By utilising this method, it is possible to make clear to students that following a geodesic in curved spacetime does not always result in the greatest experienced proper time.

  11. THE ANALYSIS OF PARADOXICAL ENGLISH STATEMENTS BY USING SCHEMES

    Directory of Open Access Journals (Sweden)

    Belyaeva, E.A.

    2017-06-01

    Full Text Available The article is aimed at studying the opportunities of implementing visual aids in teaching analytical reading methods to students at language colleges. In the first part the author analyses the category of reading technique, the tasks of teaching basic and analytical reading which are related to the object of the research. The necessity to enhance motivation and cross-cultural competence of learners due to the use of visual aids and authentic texts is being justified. The author argues the applicability of paradoxical statements for demonstration of the conceptual analysis cases. The technique of paradoxical statements’ analysis, allowing to define the key text concepts and the character of their interrelation by making up structural schemes, is being considered. In conclusion of the article examples of the analysis with interpretation and practical recommendations are provided.

  12. Interpretation of spectral paradox of cosmic X-ray background

    Institute of Scientific and Technical Information of China (English)

    李志青; 周又元

    1997-01-01

    The integrated spectrum of discrete X-ray sources (mainly the active galactic nuclei, AGN) is inconsistent with the observed spectrum of cosmic X-ray background (CXB), and it is so called CXB spectral paradox. The medium X-ray spectra of 68 AGNs are adopted, the evolution function of X-ray spectral indices is analyzed statistically, the fraction of CXB is calculated due to AGNs X-ray emission, which shows that almost 100% CXB comes from AGNs X-ray emission. Especially, the integrated spectrum in 2-10 keV is consistent with the observed spectrum of CXB. The spectral paradox of CXB can be interpreted by this result.

  13. The Critical Care Obesity Paradox and Implications for Nutrition Support.

    Science.gov (United States)

    Patel, Jayshil J; Rosenthal, Martin D; Miller, Keith R; Codner, Panna; Kiraly, Laszlo; Martindale, Robert G

    2016-09-01

    Obesity is a leading cause of preventable death worldwide. The prevalence of obesity has been increasing and is associated with an increased risk for other co-morbidities. In the critical care setting, nearly one third of patients are obese. Obese critically ill patients pose significant physical and on-physical challenges to providers, including optimization of nutrition therapy. Intuitively, obese patients would have worse critical care-related outcome. On the contrary, emerging data suggests that critically ill obese patients have improved outcomes, and this phenomenon has been coined "the obesity paradox." The purposes of this review will be to outline the historical views and pathophysiology of obesity and epidemiology of obesity, describe the challenges associated with obesity in the intensive care unit setting, review critical care outcomes in the obese, define the obesity-critical care paradox, and identify the challenges and role of nutrition support in the critically ill obese patient.

  14. Safety in the globalising knowledge economy: an analysis by paradoxes.

    Science.gov (United States)

    Ravetz, J R

    2001-09-14

    There is a widespread recognition of a 'crisis' in official scientific expertise, related to the increase of 'uncertainty' and the loss of 'trust', and whose cure is believed to lie in 'participation'. I argue that the crisis results from structural features of the globalising knowledge economy, and the contradictory roles of governments, acting both as promoters of global business enterprise and also as regulators on behalf of a sophisticated and suspicious public. I explain the crisis by substituting 'safety' for 'risk' as the operative concept, and also using 'paradox' as an explanatory tool. I produce a closed-cycle paradox, analogous to the classic Catch-22, to exhibit the contradictions in the situation. I discuss ways of resolving these, which include the recognition of policy-critical ignorance and the adoption of the perspective of post-normal science.

  15. Perception gustative des lipides alimentaires : paradigme et paradoxes

    Directory of Open Access Journals (Sweden)

    Gaillard Dany

    2008-01-01

    Full Text Available Origin of spontaneous fat preference in mammals remains elusive. It is clearly a multimodal system resulting from the integration of orosensory and post-ingestive signals. For a long time, dietary lipids were thought to be only sensed in the oral cavity through their textural and olfactory cues. Recent data strongly suggest that the sense of taste also plays a significant role in the preference for lipid-rich foods and in lipid-mediated induction of cephalic phase of the digestion in rodents and in humans. Molecular and physiological mechanisms of this new paradigm become known. Some of these data were not fully expected and might be considered, as first sight, as paradoxical. The « fatty taste » paradigm and paradoxes are analyzed in this minireview.

  16. A general realistic treatment of the disk paradox

    CERN Document Server

    Pantazis, George

    2016-01-01

    Mechanical angular momentum is not conserved in systems involving electromagnetic fields with non-zero electromagnetic field angular momentum. Conservation is restored only if the total (mechanical and field) angular momentum is considered. Previous studies have investigated this effect, known as "Feynman's Electromagnetic Paradox" or simply "Disk Paradox" in the context of idealized systems (infinite or infinitesimal solenoids and charged cylinders \\etc). In the present analysis we generalize previous studies by considering more realistic systems with finite components and demonstrating explicitly the conservation of the total angular momentum. This is achieved by expressing both the mechanical and the field angular momentum in terms of charges and magnetic field fluxes through various system components. Using this general expression we demonstrate explicitly the conservation of total angular momentum in both idealized and realistic systems (finite solenoid concentric with two charged long cylinders) taking ...

  17. The Diversity Paradox: How Nature Resolves an Evolutionary Dilemma

    CERN Document Server

    Whitacre, James M

    2011-01-01

    Adaptation to changing environments is a hallmark of biological systems. Diversity in traits is necessary for adaptation and can influence the survival of a population faced with novelty. In habitats that remain stable over many generations, stabilizing selection reduces trait differences within populations, thereby appearing to remove the diversity needed for heritable adaptive responses in new environments. Paradoxically, field studies have documented numerous populations under long periods of stabilizing selection and evolutionary stasis that have rapidly evolved under changed environmental conditions. In this article, we review how cryptic genetic variation (CGV) resolves this diversity paradox by allowing populations in a stable environment to gradually accumulate hidden genetic diversity that is revealed as trait differences when environments change. Instead of being in conflict, environmental stasis supports CGV accumulation and thus appears to facilitate rapid adaptation in new environments as suggest...

  18. Note on a paradox in decision-theoretic interval estimation

    CERN Document Server

    Kabaila, Paul

    2012-01-01

    Confidence intervals are assessed according to two criteria, namely expected length and coverage probability. In an attempt to apply the decision-theoretic method to finding a good confidence interval, a loss function that is a linear combination of the interval length and the indicator function that the interval includes the parameter of interest has been proposed. We consider the particular case that the parameter of interest is the normal mean, when the variance is unknown. Casella, Hwang and Robert, Statistica Sinica, 1993, have shown that this loss function, combined with the standard noninformative prior, leads to a generalized Bayes rule that is a confidence interval for this parameter which has "paradoxical behaviour". We show that a simple modification of this loss function, combined with the same prior, leads to a generalized Bayes rule that is the usual confidence interval i.e. the "paradoxical behaviour" is removed.

  19. Privacy Awareness: A Means to Solve the Privacy Paradox?

    Science.gov (United States)

    Pötzsch, Stefanie

    People are limited in their resources, i.e. they have limited memory capabilities, cannot pay attention to too many things at the same time, and forget much information after a while; computers do not suffer from these limitations. Thus, revealing personal data in electronic communication environments and being completely unaware of the impact of privacy might cause a lot of privacy issues later. Even if people are privacy aware in general, the so-called privacy paradox shows that they do not behave according to their stated attitudes. This paper discusses explanations for the existing dichotomy between the intentions of people towards disclosure of personal data and their behaviour. We present requirements on tools for privacy-awareness support in order to counteract the privacy paradox.

  20. Musings on Firewalls and the Information Paradox

    Directory of Open Access Journals (Sweden)

    Michael Devin

    2014-04-01

    Full Text Available The past year has seen an explosion of new and old ideas about black hole physics. Prior to the firewall paper, the dominant picture was the thermofield model apparently implied by anti-de Sitter conformal field theory duality. While some seek a narrow responce to Almheiri, Marolf, Polchinski, and Sully (AMPS , there are a number of competing models. One problem in the field is the ambiguity of the competing proposals. Some are equivalent while others incompatible. This paper will attempt to define and classify a few models representative of the current discussions.

  1. How Much Hillslope Does it Need to Solve the Double Paradox?

    Science.gov (United States)

    Lischeid, G.

    2004-12-01

    Studying the connection between catchments and stream encounters a double paradox (Kirchner 2003): First, often rapid responses of stream discharge to rainstorms are observed, although usually pre-event water predominates in the stream. That would point to a large water pool being involved in stormflow runoff generation. However, stormflow stream water usually differs significantly from baseflow, pointing to two different pools of pre-event water, and a quick switch between the both. Different mechanisms have been proposed to solve that paradox, but these were usually restricted to certain subsets of catchments. Here, a more general perceptual model is presented. It is based on a literature review and on own field work in German and Swedish catchments. For this model, the unsaturated topsoil layer of the riparian zone plays a crucial role. Although saturation excess surface runoff is widely accepted as a predominating runoff generation process, a close-up to the "saturated areas" in fact reveals more a patchy pattern of saturation due to the micro relief of the soil surface. These patches are hydraulically connected by short sub-surface flowpaths through the forest floor and uppermost mineral soil. This is sufficient to mix event water with a large pool of pre-event water, that is chemically very similar to hillslope vadose zone water. On the other hand, water transport within the saturated patches is very fast, thus explaining the rapid response of the hydrograph. Moreover, mixing of event-water with pre-event water within the riparian phreatic zone was observed during heavy rainstorms and snowmelt periods. In addition, there is strong evidence that even in the saturated zone a mobile and an immobile soil water fraction can be differentiated which is clearly at odds with the homogeneity assumption in many models. Due to its short residence time, the mobile fraction tends to resemble more the vadose zone (and thus hillslope) soil water than the immobile fraction

  2. "Paradoxical" reduction in postexercise ejection time and increased transthoracic impedance.

    Science.gov (United States)

    Nakamura, Y; Kotilainen, P; Haffty, B; Jolda, R; Bishop, R; Spodick, D

    1978-12-01

    Despite decreasing heart rate, left ventricular ejection time (LVET) transiently falls immediately following bicycle exercise. In seven normal, untrained subjects LVET decreases at 15 s postexercise corresponded (r = 0.78) with an increase in transthoracic electrical impedance (Z) consistent with decreased venous return to the thorax. Because the determinants of LVET are stroke volume (SV) and ejection rate, the deltaZ implies that decreased SV contributed to the "paradoxical" fall in LVET.

  3. Activating Knowledge Through Electronic Collaboration: Vanquishing The Knowledge Paradox

    OpenAIRE

    Qureshi, Sadja; Keen, Peter

    2004-01-01

    textabstractElectronic collaboration has become a driver for productivity as organizations develop linkages for the planning, sourcing and execution of goods and services. These organizations require mechanisms to harness the diverse and personalized intellectual resources that are distributed across the world. While electronic collaboration technologies have made it possible to harness intellectual resources across space and time, knowledge management is locked in a paradox of perception – t...

  4. Paradoxes in medicine: an access to new knowledge?

    Science.gov (United States)

    Ginter, E; Simko, V; Dolinska, S

    2009-01-01

    The analysis of health and nutrition data from various countries shows many surprising and seemingly incomprehensible facts and paradoxical relationships. Health status of a country is the result of long-term factors and therefore it cannot be changed from day to day. For example in Central European countries there was a sudden increase in life expectancy after the fall of Soviet hegemony. French paradox is the oldest example of apparent contrast between "unhealthy" nutrition and low cardiovascular mortality. Although, the consumption of animal fat and milk and milk products in Switzerland is very high, but premature cardiovascular mortality of Swiss men and women is the lowest in Europe. In USA there is concominant increase of obesity and decrease in cardiovascular mortality. In Cuba, in spite of great economic problems its relatively high male and female life expectancy is very similar to the rich USA. The life expectancy in Albania is significantly higher than in many countries in Central Europe and in the Balkan region, in spite of the fact that Albania remains the poorest European country. Analysis of these unexpected and paradoxical relations indicate the importance of the quality of medical care, control of cardiovascular risk factors (USA) and the influence of modest but biologically balanced diet on low prevalence of cardiovascular disease in Cuba and Albania. The experience from former communist Central European countries suggests important influence of chronic stress and psychosocial factors on heart diseases and life expectancy. These paradoxes open the door to new information (Fig. 5, Ref. 11). Full Text (Free, PDF) www.bmj.sk.

  5. North Korean Paradoxes. Circumstances, Costs, and Consequences of Korean Unification

    Science.gov (United States)

    2005-01-01

    paper) 1. Korean reunification question (1945- ) 2. Korea (North)-Economic policy. 3. Korea (North)--Politics and government. 4. Security, International...order@rand.org Preface This monograph, focusing on North Korea , analyzes some of the economic, political, and security issues associated with Korean ...Northeast Asia. iii iv North Korean Paradoxes This research was performed within the International Security and Defense Policy Center of the RAND National

  6. Renovation and Involution-Paradox of Chinese Literature in Modernity

    Institute of Scientific and Technical Information of China (English)

    XU Yi-bin

    2013-01-01

    With a special matter, Chinese literature has differences with traditional theories from western countries in essence, so that Chinese literature demonstrates its renovation and involution. The main reason is its trends of modernity. The transformation from oversea exchange is very important. This paper mainly explains the specific content of paradox of Chinese literature in mo-dernity, and explores the reasons for differences between China and western countries.

  7. The Historical Interpretation of the Paradox of Potatoes

    Institute of Scientific and Technical Information of China (English)

    秦梦晴; 吴建树

    2015-01-01

    Since Samuelson put forward the"potato paradox"in 1964,there have been various answers given by many economists.The passage puts forward a new opinion from two different angles:the consumption of different family types,and the measures taken by the British gov⁃ernment.The passage also answers why poor people buy more potatoes at a higher price during that time but the actual consumption of po⁃tatoes is reduced.

  8. A privacy paradox: Social networking in the United States

    OpenAIRE

    Barnes, Susan B.

    2006-01-01

    Teenagers will freely give up personal information to join social networks on the Internet. Afterwards, they are surprised when their parents read their journals. Communities are outraged by the personal information posted by young people online and colleges keep track of student activities on and off campus. The posting of personal information by teens and students has consequences. This article will discuss the uproar over privacy issues in social networks by describing a privacy paradox; p...

  9. Deconstructing the smoking-preeclampsia paradox through a counterfactual framework.

    Science.gov (United States)

    Luque-Fernandez, Miguel Angel; Zoega, Helga; Valdimarsdottir, Unnur; Williams, Michelle A

    2016-06-01

    Although smoking during pregnancy may lead to many adverse outcomes, numerous studies have reported a paradoxical inverse association between maternal cigarette smoking during pregnancy and preeclampsia. Using a counterfactual framework we aimed to explore the structure of this paradox as being a consequence of selection bias. Using a case-control study nested in the Icelandic Birth Registry (1309 women), we show how this selection bias can be explored and corrected for. Cases were defined as any case of pregnancy induced hypertension or preeclampsia occurring after 20 weeks' gestation and controls as normotensive mothers who gave birth in the same year. First, we used directed acyclic graphs to illustrate the common bias structure. Second, we used classical logistic regression and mediation analytic methods for dichotomous outcomes to explore the structure of the bias. Lastly, we performed both deterministic and probabilistic sensitivity analysis to estimate the amount of bias due to an uncontrolled confounder and corrected for it. The biased effect of smoking was estimated to reduce the odds of preeclampsia by 28 % (OR 0.72, 95 %CI 0.52, 0.99) and after stratification by gestational age at delivery ( 1, revealing the structure of the paradox. The bias-adjusted estimation of the smoking effect on preeclampsia showed an OR of 1.22 (95 %CI 0.41, 6.53). The smoking-preeclampsia paradox appears to be an example of (1) selection bias most likely caused by studying cases prevalent at birth rather than all incident cases from conception in a pregnancy cohort, (2) omitting important confounders associated with both smoking and preeclampsia (preventing the outcome to develop) and (3) controlling for a collider (gestation weeks at delivery). Future studies need to consider these aspects when studying and interpreting the association between smoking and pregnancy outcomes.

  10. Effects of adaptogens on granulocytopoiesis during paradoxical sleep deprivation.

    Science.gov (United States)

    Provalova, N V; Skurikhin, E G; Suslov, N I; Dygai, A M; Gol'dberg, E D

    2002-03-01

    We studied the effects of extracts from Siberian ginseng, Rhodiola rosea, bergenia, and ginseng (G115) and pantohematogen on granulocytopoiesis after paradoxical sleep deprivation. The effects of adaptogens on the blood system were most pronounced during hyperplasia of granulocytopoiesis. Natural preparations were divided into groups depending on their activity. Extracts of Siberian ginseng and Rhodiola rosea did not modulate granulocytopoiesis. Ginseng G115 extract suppressed granulocytopoiesis. Bergenia extract and pantohematogen produced ambiguous effects on the granulocytic hemopoietic stem.

  11. The pain paradox: borderline personality disorder features, self-harm history, and the experience of pain.

    Science.gov (United States)

    Carpenter, Ryan W; Trull, Timothy J

    2015-04-01

    Individuals with borderline personality disorder (BPD), compared to controls, report a relative absence of acute pain. In contrast, BPD is overrepresented among chronic pain patients, suggesting they experience a relative excess of chronic pain. To date, this "pain paradox" has been only partially explored; no study has examined both acute and chronic pain in the same sample. In addition, previous research has not fully examined the effect of nonsuicidal self-injury (NSSI) on either acute or chronic pain experience in BPD. Undergraduates (N = 206), oversampled for those high in BPD features, completed a Cold Pressor Task (CPT), rating their pain every 15 s over a maximum of 4 min. Following the CPT, participants completed measures of BPD features, NSSI history, past-year pain, and perceived pain tolerance. Results did not support the expected negative association between BPD features and acute pain. Multilevel modeling revealed an interaction of BPD features and NSSI history on CPT pain ratings: Among individuals in the no-NSSI group, BPD features were associated with greater acute pain. Among individuals in the NSSI group, BPD features were not significantly associated with acute pain. Results for past-year pain indicated that BPD features were associated with greater past-year pain regardless of NSSI history. This finding, coupled with the difference in the association of BPD features and acute pain between the NSSI and no-NSSI groups provides tentative evidence that the combination of BPD features and NSSI history, among nonclinical samples, is linked to a pain paradox.

  12. Dynamics of mechanical systems with two sliding contacts: new facets of Painlevé's paradox

    Science.gov (United States)

    Várkonyi, Péter L.

    2017-05-01

    We investigate the dynamics of finite degree-of-freedom, planar mechanical systems with multiple sliding, unilateral frictional point contacts. A complete classification of systems with 2 sliding contacts is given. The contact-mode based approach of rigid body mechanics is combined with linear stability analysis using a compliant contact model to determine the feasibility and the stability of every possible contact mode in each class. Special forms of non-stationary contact dynamics including "impact without collision" and "reverse chattering" are also investigated. Many types of solution inconsistency and the indeterminacy are identified and new phenomena related to Painlev\\'e"s non-existence and non-uniqueness paradoxes are discovered. Among others, we show that the non-existence paradox is not fully resolvable by considering impulsive contact forces. These results contribute to a growing body of evidence that rigid body mechanics cannot be developed into a complete and self-consistent theory in the presence of contacts and friction.

  13. Intergenerational solidarity: the paradox of reciprocity imbalance in ageing welfare states.

    Science.gov (United States)

    Thijssen, Peter

    2016-12-01

    In this article a new theoretical framework is applied to a research field that is somewhat fragmented, namely that of intergenerational solidarity in ageing welfare states. Inspired by utilitarian considerations many scholars tend to problematize the lack of reciprocity characterizing intergenerational exchanges. As some generations are longer old and more numerous they may receive excessive state-administered support of the younger generations, especially in a democratic setting. However, in reality there is limited empirical evidence of intergenerational conflict and theoretical explanations of this paradox are rare. An integrated and dynamical approach that incorporates Durkheim's solidarity theory, Honneth's intersubjective recognition theory, and the current work on reciprocal exchange is necessary in order to understand the survival of intergenerational solidarity in ageing welfare states. According to this model reciprocal recognition leading to the empathization of exchanges is the driving force of intergenerational solidarity in a prefigurative and democratized culture where the status of the young has risen dramatically. Hence, we come to the paradoxical conclusion that attempts to preserve intergenerational solidarity by openly denouncing excessive transfers and trying to bypass them institutionally sometimes might be counterproductive because they may erode their empathic underpinnings. © London School of Economics and Political Science 2016.

  14. Social Capital and Human Mortality: Explaining the Rural Paradox with County-Level Mortality Data

    Science.gov (United States)

    Jensen, Leif; Haran, Murali

    2014-01-01

    The “rural paradox” refers to standardized mortality rates in rural areas that are unexpectedly low in view of well-known economic and infrastructural disadvantages there. We explore this paradox by incorporating social capital, a promising explanatory factor that has seldom been incorporated into residential mortality research. We do so while being attentive to spatial dependence, a statistical problem often ignored in mortality research. Analyzing data for counties in the contiguous United States, we find that: (1) the rural paradox is confirmed with both metro/non-metro and rural-urban continuum codes, (2) social capital significantly reduces the impacts of residence on mortality after controlling for race/ethnicity and socioeconomic covariates, (3) this attenuation is greater when a spatial perspective is imposed on the analysis, (4) social capital is negatively associated with mortality at the county level, and (5) spatial dependence is strongly in evidence. A spatial approach is necessary in county-level analyses such as ours to yield unbiased estimates and optimal model fit. PMID:25392565

  15. Folded Supersymmetry and the LDP Paradox

    Energy Technology Data Exchange (ETDEWEB)

    Burdman, Gustavo; Chacko, Z.; Goh, Hock-Seng; Harnik, Roni

    2006-09-21

    We present a new class of models that stabilize the weak scale against radiative corrections up to scales of order 5 TeV without large corrections to precision electroweak observables. In these ''folded supersymmetric'' theories the one loop quadratic divergences of the Standard Model Higgs field are canceled by opposite spin partners, but the gauge quantum numbers of these new particles are in general different from those of the conventional superpartners. This class of models is built around the correspondence that exists in the large N limit between the correlation functions of supersymmetric theories and those of their non-supersymmetric orbifold daughters. By identifying the mechanism which underlies the cancellation of one loop quadratic divergences in these theories, we are able to construct simple extensions of the Standard Model which are radiatively stable at one loop. Ultraviolet completions of these theories can be obtained by imposing suitable boundary conditions on an appropriate supersymmetric higher dimensional theory compactified down to four dimensions. We construct a specific model based on these ideas which stabilizes the weak scale up to about 20 TeV and where the states which cancel the top loop are scalars not charged under Standard Model color. Its collider signatures are distinct from conventional supersymmetric theories and include characteristic events with hard leptons and missing energy.

  16. Solution of Supplee's submarine paradox through special and general relativity

    CERN Document Server

    Vieira, R S

    2016-01-01

    In 1989 Supplee described an apparent relativistic paradox on which a submarine seems to sink in a given frame while floating in another one. If the submarine density is adjusted to be the same as the water density (when both of them are at rest) and then it is put to move, the density of the submarine will become higher than that of the water, thanks to Lorentz contraction, and hence it sinks. However, in the submarine proper frame, is the water that becomes denser, so the submarine supposedly should float and we get a paradox situation. In this paper we analyze the submarine paradox in both a flat and a curved spacetime. In the case of a flat spacetime, we first show that any relativistic force field in special relativity can be written in the Lorentz form, so that it can always be decomposed into a static (electric-like) and a dynamic (magnetic-like) part. Taking into account the gravitomagnetic effects between the Earth and the water, a relativistic formulation of Archimedes principle can be established, ...

  17. The diagnosis and treatment of paradoxical embolism: a systematic review

    Directory of Open Access Journals (Sweden)

    Atooshe Rohani

    2016-11-01

    Full Text Available One in five adults has patent foramen ovale (PFO, which is typically without symptoms. Because of the low pressure in both atria and the anatomical position of the septum secundum, there is no left-to-right shunting and little right-to-left shunting in the general condition; however, when the right atrial pressure increases, this slit-like flap separates and allows right-to-left shunting. According to the Johnson criteria, simultaneous occurrences of arterial emboli, such as those caused by cerebrovascular accident or pulmonary embolism, demonstrate the presence of paradoxical embolism through a PFO. When a patient presents with multivascular arterial embolism, the clinician should perform a contrast transthoracic echo, a transesophageal (TEE, a real-time three-dimensional TEE, and even an intracardiac echocardiography (ICE in order to differentiate between PFO, flat atrial septal defect (ASD and hybrid defects. The randomized trials that have assessed therapeutic interventions for paradoxical embolism have not produced any clear guidelines as to how best to treat this condition. The classic treatment is surgical embolectomy with exploration of the right chambers and the pulmonary arteries under full cardiopulmonary bypass. Patients with a history of ≥1 paradoxical embolism may be indicated for device PFO closure.

  18. The paradoxes of asthma management: time for a new approach?

    Science.gov (United States)

    O'Byrne, Paul M; Jenkins, Christine; Bateman, Eric D

    2017-09-01

    Poor adherence to maintenance pharmacotherapy is a reality in asthma. Studies confirm that when symptoms worsen, most patients increase short-acting β2-agonist (SABA) use, instead of using controller medication. This behaviour might be attributable to several paradoxes in the current treatment approach. These paradoxes include the recommended use of a SABA bronchodilator alone at Global Initiative for Asthma (GINA) step 1, despite the fact that asthma is a chronic inflammatory disease. At step 1, the patient has autonomy and their perception of need and disease control is accepted, but at higher asthma treatment steps a fixed-dose approach is recommended, irrespective of symptom severity. The unintended consequence is the establishment of a pattern of early over-reliance on SABA. New approaches that avoid these paradoxes are needed, such as patient-adjusted therapy, in which patients adopt a symptom-driven approach using a combination reliever/controller. We propose that SABA reliever monotherapy should be replaced by a combination of inhaled corticosteroid (ICS) and formoterol, or similar rapid-onset bronchodilator, as reliever therapy for patients at GINA steps 1 or 2. This will ensure early and more regular administration of a controller medication. However, a significant body of clinical data will be needed before this approach can be approved by regulatory authorities. Copyright ©ERS 2017.

  19. Paradoxical response during antituberculous treatment for abdominal tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Young; Kwon, Jung Hyeok; Kim, Mi Jeong; Chang, Hyuk Won; Hwang, Jae Seok; Cho, Kwang Bum; Park, Kyung Sik; Jang, Byoung Kuk; Chung, Woo Jin [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2006-12-15

    The purpose of our study was to evaluate clinical and CT findings of paradoxical response during treatment for abdominal tuberculosis. Authors reviewed the patient records of 138 patients with abdominal tuberculosis during a recent 6-year period and we selected 11 patients with a paradoxical response. The CT findings and pathologic findings of the initial lesions and new lesions were reviewed. The intervals between initiation of therapy and the detection of new lesions, improvement of new lesion and the final follow-up were evaluated. At the initial presentation, we identified tuberculous peritonitis in 8 patients, tuberculous lymphadenitis in 3 patients and ileocolic tuberculosis in two patients. New lesions were identified at 2-10 months (mean: 3.8 months) after the initiation of therapy and following improvement of the initial lesions. The new lesions were perihepatic caseous abscess (n=4), hepatic tuberculoma (n=3), hepatic caseous abscess (n=1), tuberculous lymphadenitis (n=3), ileocolic tuberculosis (n=3), and splenic tuberculoma (n=1). Improvement of new lesions was noted at 4-14 months (mean: 7.6 months). At the final follow-up of seven patients, the new lesions disappeared and four patients still had small residual lesions. New lesions that develop in a patient with initial improvement should be considered a paradoxical response that will ultimately improve with continuation of the original medication.

  20. [Paradoxical reaction in tuberculous meningitis: a case report].

    Science.gov (United States)

    González, Norma E; Alvarez Ponte, Silvia

    2014-12-01

    The central nervous system is one of the locations of extrapulmonary tuberculosis with worse prognosis. The delay in diagnosis and treatment is one of the factors associated with higher mortality and sequelae. The "paradoxical reaction" is described as a variable degree of symptomatic deterioration during the effective treatment of tuberculosis. The increased resistance of Mycobacterium tuberculosis to drugs observed in recent years generates greater concern about the emergence of a paradoxical reaction during treatment. The case of a child with tuberculous meningitis that after one month of treatment presented clinical worsening and new lesions in CT and MRI images of the brain is presented. Comorbidities were excluded, it was verified that taking drugs has been monitored, and the sensitivity of the bacillus to first-line antituberculosis drugs was confirmed. The patient required no change in the pattern of tuberculosis treatment and steroids were administered for symptomatic relief. The paradoxical reaction during antituberculosis treatment is rare and due to a hypersensitivity reaction between the host and the tuberculous bacillus. When it appears you must ensure the effectiveness and compliance of the treatment.