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Sample records for history dependent parrondo

  1. Parrondo Games with Spatial Dependence, III

    NASA Astrophysics Data System (ADS)

    Ethier, S. N.; Lee, Jiyeon

    2015-10-01

    We study Toral’s Parrondo games with N players and one-dimensional spatial dependence as modified by Xie et al. Specifically, we use computer graphics to sketch the Parrondo and anti-Parrondo regions for 3 ≤ N ≤ 9. Our work was motivated by a recent paper of Li et al., who applied a state space reduction method to this model, reducing the number of states from 2N to N + 1. We show that their reduced Markov chains are inconsistent with the model of Xie et al.

  2. Parrondo Games with Two-Dimensional Spatial Dependence

    NASA Astrophysics Data System (ADS)

    Ethier, S. N.; Lee, Jiyeon

    Parrondo games with one-dimensional (1D) spatial dependence were introduced by Toral and extended to the two-dimensional (2D) setting by Mihailović and Rajković. MN players are arranged in an M × N array. There are three games, the fair, spatially independent game A, the spatially dependent game B, and game C, which is a random mixture or non-random pattern of games A and B. Of interest is μB (or μC), the mean profit per turn at equilibrium to the set of MN players playing game B (or game C). Game A is fair, so if μB ≤ 0 and μC > 0, then we say the Parrondo effect is present. We obtain a strong law of large numbers (SLLN) and a central limit theorem (CLT) for the sequence of profits of the set of MN players playing game B (or game C). The mean and variance parameters are computable for small arrays and can be simulated otherwise. The SLLN justifies the use of simulation to estimate the mean. The CLT permits evaluation of the standard error of a simulated estimate. We investigate the presence of the Parrondo effect for both small arrays and large ones. One of the findings of Mihailović and Rajković was that “capital evolution depends to a large degree on the lattice size.” We provide evidence that this conclusion is partly incorrect. A paradoxical feature of the 2D game B that does not appear in the 1D setting is that, for fixed M and N, the mean function μB is not necessarily a monotone function of its parameters.

  3. Beyond Parrondo's Paradox

    PubMed Central

    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

  4. Exact probability distribution functions for Parrondo's games

    NASA Astrophysics Data System (ADS)

    Zadourian, Rubina; Saakian, David B.; Klümper, Andreas

    2016-12-01

    We study the discrete time dynamics of Brownian ratchet models and Parrondo's games. Using the Fourier transform, we calculate the exact probability distribution functions for both the capital dependent and history dependent Parrondo's games. In certain cases we find strong oscillations near the maximum of the probability distribution with two limiting distributions for odd and even number of rounds of the game. Indications of such oscillations first appeared in the analysis of real financial data, but now we have found this phenomenon in model systems and a theoretical understanding of the phenomenon. The method of our work can be applied to Brownian ratchets, molecular motors, and portfolio optimization.

  5. Winning combinations of history-dependent games

    NASA Astrophysics Data System (ADS)

    Kay, Roland J.; Johnson, Neil F.

    2003-05-01

    The Parrondo effect describes the seemingly paradoxical situation in which two losing games can, when combined, become a winning game [Parrondo, Harmer, and Abbott, Phys. Rev. Lett. 85, 24 (2000)]. Here, we generalize this analysis to the case where both games are history dependent, i.e., there is an intrinsic memory in the dynamics of each game. Results are presented for the cases of both random and periodic switching between the two games.

  6. Parrondo's games with strategy

    NASA Astrophysics Data System (ADS)

    Van den Broeck, Christian P.; Cleuren, Bart

    2004-05-01

    The notion of a strategy in the multi-player version of the Parrondo game is reviewed. We calculate the gain for the greedy strategy as a function of the number N of players, including exact analytic results for N < 4 and in the limit N-->∞. We show that the greedy strategy is optimal for N = 1 and N = 2 but not for N = 3. In the limit N-->∞ our analysis reveals a very rich behavior including the possibility of phase transitions as a function of the chosen strategy.

  7. Parrondo's games and the zipping algorithm

    NASA Astrophysics Data System (ADS)

    Amengual, Pau; Toral, Raul

    2004-05-01

    We study the relation between the discrete-time version of the flashing ratchet known as Parrondo's games and a compression technique used very recently with thermal ratchets for evaluating the transfer of information -- negentropy -- between the Brownian particle and the source of fluctuations. We present some results concerning different versions of Parrondo's games showing, for each case, a good qualitative agreement between the gain and the inverse of the entropy.

  8. Extended Parrondo's game and Brownian ratchets: strong and weak Parrondo effect.

    PubMed

    Wu, Degang; Szeto, Kwok Yip

    2014-02-01

    Inspired by the flashing ratchet, Parrondo's game presents an apparently paradoxical situation. Parrondo's game consists of two individual games, game A and game B. Game A is a slightly losing coin-tossing game. Game B has two coins, with an integer parameter M. If the current cumulative capital (in discrete unit) is a multiple of M, an unfavorable coin p(b) is used, otherwise a favorable p(g) coin is used. Paradoxically, a combination of game A and game B could lead to a winning game, which is the Parrondo effect. We extend the original Parrondo's game to include the possibility of M being either M(1) or M(2). Also, we distinguish between strong Parrondo effect, i.e., two losing games combine to form a winning game, and weak Parrondo effect, i.e., two games combine to form a better-performing game. We find that when M(2) is not a multiple of M(1), the combination of B(M(1)) and B(M(2)) has strong and weak Parrondo effect for some subsets in the parameter space (p(b),p(g)), while there is neither strong nor weak effect when M(2) is a multiple of M(1). Furthermore, when M(2) is not a multiple of M(1), a stochastic mixture of game A may cancel the strong and weak Parrondo effect. Following a discretization scheme in the literature of Parrondo's game, we establish a link between our extended Parrondo's game with the analysis of discrete Brownian ratchet. We find a relation between the Parrondo effect of our extended model to the macroscopic bias in a discrete ratchet. The slope of a ratchet potential can be mapped to the fair game condition in the extended model, so that under some conditions, the macroscopic bias in a discrete ratchet can provide a good predictor for the game performance of the extended model. On the other hand, our extended model suggests a design of a ratchet in which the potential is a mixture of two periodic potentials.

  9. Extended Parrondo's game and Brownian ratchets: Strong and weak Parrondo effect

    NASA Astrophysics Data System (ADS)

    Wu, Degang; Szeto, Kwok Yip

    2014-02-01

    Inspired by the flashing ratchet, Parrondo's game presents an apparently paradoxical situation. Parrondo's game consists of two individual games, game A and game B. Game A is a slightly losing coin-tossing game. Game B has two coins, with an integer parameter M. If the current cumulative capital (in discrete unit) is a multiple of M, an unfavorable coin pb is used, otherwise a favorable pg coin is used. Paradoxically, a combination of game A and game B could lead to a winning game, which is the Parrondo effect. We extend the original Parrondo's game to include the possibility of M being either M1 or M2. Also, we distinguish between strong Parrondo effect, i.e., two losing games combine to form a winning game, and weak Parrondo effect, i.e., two games combine to form a better-performing game. We find that when M2 is not a multiple of M1, the combination of B (M1) and B (M2) has strong and weak Parrondo effect for some subsets in the parameter space (pb,pg), while there is neither strong nor weak effect when M2 is a multiple of M1. Furthermore, when M2 is not a multiple of M1, a stochastic mixture of game A may cancel the strong and weak Parrondo effect. Following a discretization scheme in the literature of Parrondo's game, we establish a link between our extended Parrondo's game with the analysis of discrete Brownian ratchet. We find a relation between the Parrondo effect of our extended model to the macroscopic bias in a discrete ratchet. The slope of a ratchet potential can be mapped to the fair game condition in the extended model, so that under some conditions, the macroscopic bias in a discrete ratchet can provide a good predictor for the game performance of the extended model. On the other hand, our extended model suggests a design of a ratchet in which the potential is a mixture of two periodic potentials.

  10. Optimal strategies in collective Parrondo games

    NASA Astrophysics Data System (ADS)

    Dinis, L.; Parrondo, J. M. R.

    2003-08-01

    We present a modification of the so-called Parrondo's paradox where one is allowed to choose in each turn the game that a large number of individuals play. It turns out that, by choosing the game which gives the highest average earnings at each step, one ends up with systematic losses, whereas a periodic or random sequence of choices yields a steadily increase of the capital. An explanation of this behavior is given by noting that the short-range maximization of the returns is "killing the goose that laid the golden eggs". A continuous model displaying similar features is analyzed using dynamic programming techniques from control theory.

  11. A Fokker-Planck description for Parrondo's games

    NASA Astrophysics Data System (ADS)

    Toral, Raul; Amengual, Pau; Mangioni, Sergio

    2003-05-01

    We discuss in detail two recently proposed relations between the Parrondo's games and the Fokker-Planck equation describing the flashing ratchet as the overdamped motion of a particle in a potential landscape. In both cases it is possible to relate exactly the probabilities of the games to the potential in which the overdamped particle moves. We will discuss under which conditions current-less potentials correspond to fair games and vie versa.

  12. Winning in sequential Parrondo games by players with short-term memory

    NASA Astrophysics Data System (ADS)

    Cheung, K. W.; Ma, H. F.; Wu, D.; Lui, G. C.; Szeto, K. Y.

    2016-05-01

    The original Parrondo game, denoted as AB3, contains two independent games: A and B. The winning or losing of games A and B is defined by the change of one unit of capital. Game A is a losing game if played continuously, with winning probability p=0.5-ε , where ε =0.003 . Game B is also losing and has two coins: a good coin with winning probability {{p}\\text{g}}=0.75-ε is used if the player’s capital is not divisible by 3, otherwise a bad coin with winning probability {{p}\\text{b}}=0.1-ε is used. The Parrondo paradox refers to the situation where the mixture of games A and B in a sequence leads to winning in the long run. The paradox can be resolved using Markov chain analysis. We extend this setting of the Parrondo game to involve players with one-step memory. The player can win by switching his choice of A or B game in a Parrondo game sequence. If the player knows the identity of the game he plays and the state of his capital, then the player can win maximally. On the other hand, if the player does not know the nature of the game, then he is playing a (C, D) game, where either (C  =  A, D  =  B), or (C  =  B, D  =  A). For a player with one-step memory playing the AB3 game, he can achieve the highest expected gain with switching probability equal to 3/4 in the (C, D) game sequence. This result has been found first numerically and then proven analytically. Generalization to an AB mod(M) Parrondo game for other integers M has been made for the general domain of parameters {{p}\\text{b}}\\text{A}}<{{p}\\text{g}} . We find that for odd M the Parrondo effect does exist. However, for even M, there is no Parrondo effect for two cases: the initial game is A and the initial capital is even, or the initial game is B and the initial capital is odd. There is still a possibility of the Parrondo effect for the other two cases when M is even: the initial game is A and the initial capital is odd, or the initial game is B and the initial

  13. ''Illusion of control'' in Time-Horizon Minority and Parrondo Games

    NASA Astrophysics Data System (ADS)

    Satinover, J. B.; Sornette, D.

    2007-12-01

    Human beings like to believe they are in control of their destiny. This ubiquitous trait seems to increase motivation and persistence, and is probably evolutionarily adaptive [J.D. Taylor, S.E. Brown, Psych. Bull. 103, 193 (1988); A. Bandura, Self-efficacy: the exercise of control (WH Freeman, New York, 1997)]. But how good really is our ability to control? How successful is our track record in these areas? There is little understanding of when and under what circumstances we may over-estimate [E. Langer, J. Pers. Soc. Psych. 7, 185 (1975)] or even lose our ability to control and optimize outcomes, especially when they are the result of aggregations of individual optimization processes. Here, we demonstrate analytically using the theory of Markov Chains and by numerical simulations in two classes of games, the Time-Horizon Minority Game [M.L. Hart, P. Jefferies, N.F. Johnson, Phys. A 311, 275 (2002)] and the Parrondo Game [J.M.R. Parrondo, G.P. Harmer, D. Abbott, Phys. Rev. Lett. 85, 5226 (2000); J.M.R. Parrondo, How to cheat a bad mathematician (ISI, Italy, 1996)], that agents who optimize their strategy based on past information may actually perform worse than non-optimizing agents. In other words, low-entropy (more informative) strategies under-perform high-entropy (or random) strategies. This provides a precise definition of the “illusion of control” in certain set-ups a priori defined to emphasize the importance of optimization.

  14. Parrondo-like behavior in continuous-time random walks with memory

    NASA Astrophysics Data System (ADS)

    Montero, Miquel

    2011-11-01

    The continuous-time random walk (CTRW) formalism can be adapted to encompass stochastic processes with memory. In this paper we will show how the random combination of two different unbiased CTRWs can give rise to a process with clear drift, if one of them is a CTRW with memory. If one identifies the other one as noise, the effect can be thought of as a kind of stochastic resonance. The ultimate origin of this phenomenon is the same as that of the Parrondo paradox in game theory.

  15. Random Walks in the Presence of Absorbing Barriers in Parrondo's Games

    NASA Astrophysics Data System (ADS)

    Yang, Liu; Zheng, Kai-Xuan; Xie, Neng-Gang; Ye, Ye; Wang, Lu

    2015-10-01

    For a multi-agent spatial Parrondo's model that it is composed of games A and B, we use the discrete time Markov chains to derive the probability transition matrix. Then, we respectively deduce the stationary distribution for games A and B played individually and the randomized combination of game A + B. We notice that under a specific set of parameters, two absorbing states instead of a fixed stationary distribution exist in game B. However, the randomized game A + B can jump out of the absorbing states of game B and has a fixed stationary distribution because of the "agitating" role of game A. Moreover, starting at different initial states, we deduce the probabilities of absorption at the two absorbing barriers.

  16. Impact of HIV and a history of marijuana dependence on procedural learning among individuals with a history of substance dependence.

    PubMed

    Gonzalez, Raul; Schuster, Randi M; Vassileva, Jasmin; Martin, Eileen M

    2011-08-01

    Marijuana (MJ) use and HIV infection are both associated with neurocognitive deficits, yet there is little research to date examining their interactions, specifically how they pertain to procedural learning (PL). We examined a sample of 86 individuals with a history of dependence for multiple substances who underwent a comprehensive evaluation including measures of mental health, substance use history, and three measures of PL: the photoelectric Rotary Pursuit Task (RPT), the Star Mirror Tracing Task (SMT), and the Weather Prediction Task (WPT). We found that a positive HIV serostatus and a history of marijuana dependence were both independently associated with overall poorer performance on the SMT and RPT in this sample of individuals with a history of dependence for multiple substances. Rate of improvement across trial blocks did not differ as a function of HIV serostatus or history of marijuana dependence. Although we found no significant HIV × MJ interaction for any of the PL tasks, we did observe evidence of additive negative effects from HIV and a history of marijuana dependence on overall performance on the SMT and RPT, but not the WPT. The findings suggest that complex motor skills are adversely affected among abstinent polysubstance users with a history of marijuana dependence and that such deficits are compounded by HIV.

  17. Consideration of history dependent damage in creep crack growth

    SciTech Connect

    Brust, F.W. Jr.; Krishnaswamy, P.; Majumdar, B.S.

    1992-12-31

    The effects of load history on the creep crack growth process are discussed. There are three aspects of this problem which are considered: (i) the constitutive response of materials undergoing history dependent creep straining, (ii) the corresponding crack growth behavior including a discussion of fracture parameters capable of predicting the response, and (iii) experimental evidence of the importance of history dependent response. Finally, numerical studies which use the constitutive model and fracture theory of (i) and (ii) respectively are used to examine the experimental results developed in (iii).

  18. Consideration of history dependent damage in creep crack growth

    SciTech Connect

    Brust, F.W. Jr.; Krishnaswamy, P.; Majumdar, B.S.

    1992-01-01

    The effects of load history on the creep crack growth process are discussed. There are three aspects of this problem which are considered: (i) the constitutive response of materials undergoing history dependent creep straining, (ii) the corresponding crack growth behavior including a discussion of fracture parameters capable of predicting the response, and (iii) experimental evidence of the importance of history dependent response. Finally, numerical studies which use the constitutive model and fracture theory of (i) and (ii) respectively are used to examine the experimental results developed in (iii).

  19. Sex differences amongst dependent heroin users: histories, clinical characteristics and predictors of other substance dependence

    PubMed Central

    Shand, Fiona L; Degenhardt, Louisa; Slade, Tim; Nelson, Elliot C

    2010-01-01

    Introduction and aims To examine differences in the characteristics and histories of male and female dependent heroin users, and in the clinical characteristics associated with multiple substance dependence diagnoses. Design and methods 1513 heroin dependent participants underwent an interview covering substance use and dependence, psychiatric history, child maltreatment, family background, adult violence and criminal history. Family background, demographic and clinical characteristics were analysed by sex. Ordinal regression was used to test for a relationship between number of substance dependence diagnoses and other clinical variables. Results Women were more likely to experience most forms of child maltreatment, to first use heroin with a boyfriend or partner, to experience ongoing adult violence at the hands of a partner, and to have a poorer psychiatric history than men. Males had more prevalent lifetime substance dependence diagnoses and criminal histories and were more likely to meet criteria for ASPD. Predictors of multiple substance dependence diagnoses for both sexes were mental health variables, antisocial behaviour, childhood sexual abuse, victim of adult violence, younger age at first cannabis use and overdose. As the number of dependence diagnoses increased, clinical and behavioural problems increased. Childhood emotional neglect was related to increasing dependence diagnoses for females but not males, whereas PTSD was a significant predictor for males but not females. Discussion and conclusions Mental health problems, other substance dependence, childhood and adult trauma were common in this sample, with sex differences indicating different treatment needs and possible different pathways to heroin dependence for men and women. PMID:20833480

  20. Viscoplastic constitutive relationships with dependence on thermomechanical history

    NASA Technical Reports Server (NTRS)

    Robinson, D. N.; Bartolotta, P. A.

    1985-01-01

    Experimental evidence of thermomechanical history dependence in the cyclic hardening behavior of some common high-temperature structural alloys is presented with special emphasis on dynamic metallurgical changes. The inadequacy of formulating nonisothermal constitutive equations solely on the basis of isothermal testing is discussed. A representation of thermoviscoplasticity is proposed that qualitatively accounts for the observed hereditary behavior. This is achieved by formulating the scalar evolutionary equation in an established viscoplasticity theory to reflect thermomechanical path dependence. To assess the importance of accounting for thermomechanical history dependence in practical structural analyses, two qualitative models are specified: (1) formulated as if based entirely on isothermal information; (2) to reflect thermomechanical path dependence using the proposed thermoviscoplastic representation. Predictions of the two models are compared and the impact the calculated differences in deformation behavior may have on subsequent lifetime predictions is discussed.

  1. History dependent quantum random walks as quantum lattice gas automata

    SciTech Connect

    Shakeel, Asif E-mail: dmeyer@math.ucsd.edu Love, Peter J. E-mail: dmeyer@math.ucsd.edu; Meyer, David A. E-mail: dmeyer@math.ucsd.edu

    2014-12-15

    Quantum Random Walks (QRW) were first defined as one-particle sectors of Quantum Lattice Gas Automata (QLGA). Recently, they have been generalized to include history dependence, either on previous coin (internal, i.e., spin or velocity) states or on previous position states. These models have the goal of studying the transition to classicality, or more generally, changes in the performance of quantum walks in algorithmic applications. We show that several history dependent QRW can be identified as one-particle sectors of QLGA. This provides a unifying conceptual framework for these models in which the extra degrees of freedom required to store the history information arise naturally as geometrical degrees of freedom on the lattice.

  2. Dependence of CdTe response of bias history

    SciTech Connect

    Sites, J.R.; Sasala, R.A.; Eisgruber, I.L.

    1995-11-01

    Several time-dependent effect have been observed in CdTe cells and modules in recent years. Some appear to be related to degradation at the back contact, some to changes in temperature at the thin-film junction, and some to the bias history of the cell or module. Back-contact difficulties only occur in some cases, and the other two effects are reversible. Nevertheless, confusion in data interpretation can arise when these effects are not characterized. This confusion can be particularly acute when more than one time-dependent effect occurs during the same measurement cycle. The purpose of this presentation is to help categorize time-dependent effects in CdTe and other thin-film cells to elucidate those related to bias history, and to note differences between cell and module analysis.

  3. A history dependent damage model for low cycle fatigue

    NASA Technical Reports Server (NTRS)

    Leis, B. N.

    1984-01-01

    This paper examines damage assessment and accumulation. A nonlinear damage postulate is advanced that embodies the dependence of the damage rate on cycle-dependent changes in the bulk microstructure and the surface topography. The postulate is analytically formulated in terms of the deformation history dependence of the bulk behavior. This formulation is used in conjunction with baseline data in accordance with the damage postulate to predict the low cycle fatigue resistance of OFE copper. Close comparison of the predictions with observed behavior suggests the postulate offers a viable basis for nonlinear damage analysis.

  4. A history dependent damage model for low cycle fatigue

    NASA Technical Reports Server (NTRS)

    Leis, B. N.

    1984-01-01

    This paper examines damage assessment and accumulation. A nonlinear damage postulate is advanced that embodies the dependence of the damage rate on cycle-dependent changes in the bulk microstructure and the surface topography. The postulate is analytically formulated in terms of the deformation history dependence of the bulk behavior. This formulation is used in conjunction with baseline data in accordance with the damage postulate to predict the low cycle fatigue resistance of OFE copper. Close comparison of the predictions with observed behavior suggests the postulate offers a viable basis for nonlinear damage analysis.

  5. Evidence for history-dependence of influenza pandemic emergence

    NASA Astrophysics Data System (ADS)

    Hill, Edward M.; Tildesley, Michael J.; House, Thomas

    2017-03-01

    Influenza A viruses have caused a number of global pandemics, with considerable mortality in humans. Here, we analyse the time periods between influenza pandemics since 1700 under different assumptions to determine whether the emergence of new pandemic strains is a memoryless or history-dependent process. Bayesian model selection between exponential and gamma distributions for these time periods gives support to the hypothesis of history-dependence under eight out of nine sets of modelling assumptions. Using the fitted parameters to make predictions shows a high level of variability in the modelled number of pandemics from 2010–2110. The approach we take here relies on limited data, so is uncertain, but it provides cheap, safe and direct evidence relating to pandemic emergence, a field where indirect measurements are often made at great risk and cost.

  6. Evidence for history-dependence of influenza pandemic emergence.

    PubMed

    Hill, Edward M; Tildesley, Michael J; House, Thomas

    2017-03-02

    Influenza A viruses have caused a number of global pandemics, with considerable mortality in humans. Here, we analyse the time periods between influenza pandemics since 1700 under different assumptions to determine whether the emergence of new pandemic strains is a memoryless or history-dependent process. Bayesian model selection between exponential and gamma distributions for these time periods gives support to the hypothesis of history-dependence under eight out of nine sets of modelling assumptions. Using the fitted parameters to make predictions shows a high level of variability in the modelled number of pandemics from 2010-2110. The approach we take here relies on limited data, so is uncertain, but it provides cheap, safe and direct evidence relating to pandemic emergence, a field where indirect measurements are often made at great risk and cost.

  7. Evidence for history-dependence of influenza pandemic emergence

    PubMed Central

    Hill, Edward M.; Tildesley, Michael J.; House, Thomas

    2017-01-01

    Influenza A viruses have caused a number of global pandemics, with considerable mortality in humans. Here, we analyse the time periods between influenza pandemics since 1700 under different assumptions to determine whether the emergence of new pandemic strains is a memoryless or history-dependent process. Bayesian model selection between exponential and gamma distributions for these time periods gives support to the hypothesis of history-dependence under eight out of nine sets of modelling assumptions. Using the fitted parameters to make predictions shows a high level of variability in the modelled number of pandemics from 2010–2110. The approach we take here relies on limited data, so is uncertain, but it provides cheap, safe and direct evidence relating to pandemic emergence, a field where indirect measurements are often made at great risk and cost. PMID:28252671

  8. A DEM contact model for history-dependent powder flows

    NASA Astrophysics Data System (ADS)

    Hashibon, Adham; Schubert, Raphael; Breinlinger, Thomas; Kraft, Torsten

    2016-11-01

    Die filling is an important part of the powder handling process chain that greatly influences the characteristic structure and properties of the final part. Predictive modelling and simulation of the die-filling process can greatly contribute to the optimization of the part and the whole production procedure, e.g. by predicting the resulting powder compaction structure as a function of filling process parameters. The rheology of powders can be very difficult to model especially if heterogeneous agglomeration or time-dependent consolidation effects occur. We present a new discrete element contact force model that enables modelling complex powder flow characteristics including direct time-dependent consolidation effects and load history-dependent cohesion to describe the filling process of complex, difficult to handle powders. The model is demonstrated for simple flow and an industrial powder flow.

  9. Incorporating history dependence and texture in models of mantle convection

    NASA Astrophysics Data System (ADS)

    Wookey, J.; Walker, A. M.; Davies, R.; Davies, J. H.

    2012-12-01

    Solid state deformation processes permitting convection of Earth's rocky mantle necessarily lead to strong feedbacks between the deformation history and the instantaneous flow field. Mechanisms leading to the history dependence include the alignment of mineral grains with the attendant generation of elastic and rheological anisotropy, as well as processes operating at larger and smaller length scales (e.g. phase separation, grain size reduction, changes to the defect chemistry and dislocation multiplication and entanglement). Despite their sophistication, current models of mantle dynamics frequently ignore history dependent rheologies, and the feedback between deformation, grain size, crystal orientation, chemistry and viscosity. These processes have huge effects on viscosity: in the crust, they lead to the development of shear-zones and highly localised deformation, whilst, in the mantle, they are nearly always ignored. Here we describe an approach intended to introduce the consequences of history dependence into models of whole-mantle convection. We make use of existing technology that exists in several convection codes: the ability to track markers, or particles, through the evolving flow field. Tracers have previously been used to track attributes such as the bulk chemical composition or trace element ratios. Our modification is to use this technology to track a description of the current state of the texture and microstructure (encompassing an orientation distribution function, grain size parameters and dislocation density) such that we can advance models of polycrystalline deformation for many particles alongside and in sync with models of mantle convection. Our approach is intended to be reasonably generic, coupling one of several mantle convection engines with a choice of polycrystalline deformation models, but the initial implementation uses the TERRA convection code (Baumgardner, J. Stat. Phys. 39:501-511, 1985; Davies and Davies, EPSL 278:50-54, 2009) to

  10. History-dependent dissipative vortex dynamics in superconducting arrays

    DOE PAGES

    Durkin, Malcolm; Mondragon-Shem, Ian; Eley, Serena Merteen; ...

    2016-07-14

    In this study, we perform current (I)-voltage (V) measurements on low resistance superconductor-normal-superconductor arrays in finite magnetic fields, focusing on the dilute vortex population regime. We observe significant deviations from predicted behavior, notably the absence of a differential resistance peak near the vortex depinning current, and a broad linear I-V region with an extrapolated I intercept equal to the depinning current. Comparing these results to an overdamped molecular vortex model, we find that this behavior can be explained by the presence of a history-dependent dissipative force. Lastly, this approach has not been considered previously, to our knowledge, yet it ismore » crucial for obtaining a correct description of the vortex dynamics in superconducting arrays.« less

  11. History-dependent dissipative vortex dynamics in superconducting arrays

    SciTech Connect

    Durkin, Malcolm; Mondragon-Shem, Ian; Eley, Serena Merteen; Hughes, Taylor L.; Mason, Nadya

    2016-07-14

    In this study, we perform current (I)-voltage (V) measurements on low resistance superconductor-normal-superconductor arrays in finite magnetic fields, focusing on the dilute vortex population regime. We observe significant deviations from predicted behavior, notably the absence of a differential resistance peak near the vortex depinning current, and a broad linear I-V region with an extrapolated I intercept equal to the depinning current. Comparing these results to an overdamped molecular vortex model, we find that this behavior can be explained by the presence of a history-dependent dissipative force. Lastly, this approach has not been considered previously, to our knowledge, yet it is crucial for obtaining a correct description of the vortex dynamics in superconducting arrays.

  12. History-dependent dissipative vortex dynamics in superconducting arrays

    SciTech Connect

    Durkin, Malcolm; Mondragon-Shem, Ian; Eley, Serena Merteen; Hughes, Taylor L.; Mason, Nadya

    2016-07-14

    In this study, we perform current (I)-voltage (V) measurements on low resistance superconductor-normal-superconductor arrays in finite magnetic fields, focusing on the dilute vortex population regime. We observe significant deviations from predicted behavior, notably the absence of a differential resistance peak near the vortex depinning current, and a broad linear I-V region with an extrapolated I intercept equal to the depinning current. Comparing these results to an overdamped molecular vortex model, we find that this behavior can be explained by the presence of a history-dependent dissipative force. Lastly, this approach has not been considered previously, to our knowledge, yet it is crucial for obtaining a correct description of the vortex dynamics in superconducting arrays.

  13. History-dependent dissipative vortex dynamics in superconducting arrays

    NASA Astrophysics Data System (ADS)

    Durkin, Malcolm; Mondragon-Shem, Ian; Eley, Serena; Hughes, Taylor L.; Mason, Nadya

    2016-07-01

    We perform current (I )-voltage (V ) measurements on low resistance superconductor-normal-superconductor arrays in finite magnetic fields, focusing on the dilute vortex population regime. We observe significant deviations from predicted behavior, notably the absence of a differential resistance peak near the vortex depinning current, and a broad linear I -V region with an extrapolated I intercept equal to the depinning current. Comparing these results to an overdamped molecular vortex model, we find that this behavior can be explained by the presence of a history-dependent dissipative force. This approach has not been considered previously, to our knowledge, yet it is crucial for obtaining a correct description of the vortex dynamics in superconducting arrays.

  14. History dependence of vital capacity in constricted lungs.

    PubMed

    Olson, Thomas P; Wilson, Theodore A; Johnson, Bruce D; Hyatt, Robert E

    2010-07-01

    Measurements of dynamic force-length behavior of maximally activated strips of smooth muscle during oscillatory length changes show that force decreases well below the isometric force during the shortening phase of the oscillation. The magnitude of the decrease depends on the rate of shortening; for slower shortening, the decrease is smaller and force is larger. Modeling of expiratory flow, based on these data, predicts that vital capacity in constricted lungs depends on the rate of expiration. In maximally constricted lungs, forced vital capacity (FVC) is predicted to be 16% smaller than control, and vital capacity for a very slow expiration (SVC), 31% less than control. These predictions were tested by measuring FVC and SVC in constricted normal subjects. In the first group of 9 subjects, four maneuvers were made following the delivery of two doses of methacholine in the order: SVC, FVC, FVC, SVC. In a second group of 11 subjects, two maneuvers were performed at each dose in the order: FVC, SVC. At the highest dose of methacholine, FVC for both trials in group 1 and for the one trial in group 2 were all approximately 13% less than control, a slightly smaller decrease than predicted. SVC for the 1st trial in group 1 was 27% less than control, also slightly smaller than predicted. The difference between FVC and SVC for this trial, 13%, was close to the predicted difference of 15%. However, SVC for the 2nd trial in group 1 (preceded by 3 vital capacity maneuvers) and for group 2 (preceded by 1) were no different from FVC. We conclude that vital capacity in constricted lungs depends on the dynamic force-length properties of smooth muscle and that the history dependence of the dynamic properties of smooth muscle is more complicated than has been inferred from oscillatory force-length behavior.

  15. A History of Spike-Timing-Dependent Plasticity

    PubMed Central

    Markram, Henry; Gerstner, Wulfram; Sjöström, Per Jesper

    2011-01-01

    How learning and memory is achieved in the brain is a central question in neuroscience. Key to today’s research into information storage in the brain is the concept of synaptic plasticity, a notion that has been heavily influenced by Hebb's (1949) postulate. Hebb conjectured that repeatedly and persistently co-active cells should increase connective strength among populations of interconnected neurons as a means of storing a memory trace, also known as an engram. Hebb certainly was not the first to make such a conjecture, as we show in this history. Nevertheless, literally thousands of studies into the classical frequency-dependent paradigm of cellular learning rules were directly inspired by the Hebbian postulate. But in more recent years, a novel concept in cellular learning has emerged, where temporal order instead of frequency is emphasized. This new learning paradigm – known as spike-timing-dependent plasticity (STDP) – has rapidly gained tremendous interest, perhaps because of its combination of elegant simplicity, biological plausibility, and computational power. But what are the roots of today’s STDP concept? Here, we discuss several centuries of diverse thinking, beginning with philosophers such as Aristotle, Locke, and Ribot, traversing, e.g., Lugaro’s plasticità and Rosenblatt’s perceptron, and culminating with the discovery of STDP. We highlight interactions between theoretical and experimental fields, showing how discoveries sometimes occurred in parallel, seemingly without much knowledge of the other field, and sometimes via concrete back-and-forth communication. We point out where the future directions may lie, which includes interneuron STDP, the functional impact of STDP, its mechanisms and its neuromodulatory regulation, and the linking of STDP to the developmental formation and continuous plasticity of neuronal networks. PMID:22007168

  16. A history of spike-timing-dependent plasticity.

    PubMed

    Markram, Henry; Gerstner, Wulfram; Sjöström, Per Jesper

    2011-01-01

    How learning and memory is achieved in the brain is a central question in neuroscience. Key to today's research into information storage in the brain is the concept of synaptic plasticity, a notion that has been heavily influenced by Hebb's (1949) postulate. Hebb conjectured that repeatedly and persistently co-active cells should increase connective strength among populations of interconnected neurons as a means of storing a memory trace, also known as an engram. Hebb certainly was not the first to make such a conjecture, as we show in this history. Nevertheless, literally thousands of studies into the classical frequency-dependent paradigm of cellular learning rules were directly inspired by the Hebbian postulate. But in more recent years, a novel concept in cellular learning has emerged, where temporal order instead of frequency is emphasized. This new learning paradigm - known as spike-timing-dependent plasticity (STDP) - has rapidly gained tremendous interest, perhaps because of its combination of elegant simplicity, biological plausibility, and computational power. But what are the roots of today's STDP concept? Here, we discuss several centuries of diverse thinking, beginning with philosophers such as Aristotle, Locke, and Ribot, traversing, e.g., Lugaro's plasticità and Rosenblatt's perceptron, and culminating with the discovery of STDP. We highlight interactions between theoretical and experimental fields, showing how discoveries sometimes occurred in parallel, seemingly without much knowledge of the other field, and sometimes via concrete back-and-forth communication. We point out where the future directions may lie, which includes interneuron STDP, the functional impact of STDP, its mechanisms and its neuromodulatory regulation, and the linking of STDP to the developmental formation and continuous plasticity of neuronal networks.

  17. Brain development and predation: plastic responses depend on evolutionary history.

    PubMed

    Gonda, Abigél; Välimäki, Kaisa; Herczeg, Gábor; Merilä, Juha

    2012-04-23

    Although the brain is known to be a very plastic organ, the effects of common ecological interactions like predation or competition on brain development have remained largely unexplored. We reared nine-spined sticklebacks (Pungitius pungitius) from two coastal marine (predation-adapted) and two isolated pond (competition-adapted) populations in a factorial experiment, manipulating perceived predatory risk and food supply to see (i) if the treatments affected brain development and (ii) if there was population differentiation in the response to treatments. We detected differences in plasticity of the bulbus olfactorius (chemosensory centre) between habitats: marine fish were not plastic, whereas pond fish had larger bulbi olfactorii in the presence of perceived predation. Marine fish had larger bulbus olfactorius overall. Irrespective of population origin, the hypothalamus was smaller in the presence of perceived predatory risk. Our results demonstrate that perceived predation risk can influence brain development, and that the effect of an environmental factor on brain development may depend on the evolutionary history of a given population in respect to this environmental factor.

  18. Dynamics of history-dependent epidemics in temporal networks

    NASA Astrophysics Data System (ADS)

    Sunny, Albert; Kotnis, Bhushan; Kuri, Joy

    2015-08-01

    The structural properties of temporal networks often influence the dynamical processes that occur on these networks, e.g., bursty interaction patterns have been shown to slow down epidemics. In this paper, we investigate the effect of link lifetimes on the spread of history-dependent epidemics. We formulate an analytically tractable activity-driven temporal network model that explicitly incorporates link lifetimes. For Markovian link lifetimes, we use mean-field analysis for computing the epidemic threshold, while the effect of non-Markovian link lifetimes is studied using simulations. Furthermore, we also study the effect of negative correlation between the number of links spawned by an individual and the lifetimes of those links. Such negative correlations may arise due to the finite cognitive capacity of the individuals. Our investigations reveal that heavy-tailed link lifetimes slow down the epidemic, while negative correlations can reduce epidemic prevalence. We believe that our results help shed light on the role of link lifetimes in modulating diffusion processes on temporal networks.

  19. Brain development and predation: plastic responses depend on evolutionary history

    PubMed Central

    Gonda, Abigél; Välimäki, Kaisa; Herczeg, Gábor; Merilä, Juha

    2012-01-01

    Although the brain is known to be a very plastic organ, the effects of common ecological interactions like predation or competition on brain development have remained largely unexplored. We reared nine-spined sticklebacks (Pungitius pungitius) from two coastal marine (predation-adapted) and two isolated pond (competition-adapted) populations in a factorial experiment, manipulating perceived predatory risk and food supply to see (i) if the treatments affected brain development and (ii) if there was population differentiation in the response to treatments. We detected differences in plasticity of the bulbus olfactorius (chemosensory centre) between habitats: marine fish were not plastic, whereas pond fish had larger bulbi olfactorii in the presence of perceived predation. Marine fish had larger bulbus olfactorius overall. Irrespective of population origin, the hypothalamus was smaller in the presence of perceived predatory risk. Our results demonstrate that perceived predation risk can influence brain development, and that the effect of an environmental factor on brain development may depend on the evolutionary history of a given population in respect to this environmental factor. PMID:21957092

  20. A Review of the History of Field Dependence.

    ERIC Educational Resources Information Center

    Heesacker, Martin

    This paper reviews 35 studies important in the historical development of field dependence, a popular research topic in psychology. The first section involves antecedents of the concept of field dependence, such as the influence of Kurt Lewin. Part two deals with the development of field dependence as an individual differences variable. Part three…

  1. A Review of the History of Field Dependence.

    ERIC Educational Resources Information Center

    Heesacker, Martin

    This paper reviews 35 studies important in the historical development of field dependence, a popular research topic in psychology. The first section involves antecedents of the concept of field dependence, such as the influence of Kurt Lewin. Part two deals with the development of field dependence as an individual differences variable. Part three…

  2. Time-dependent regulation of yeast glycolysis upon nitrogen starvation depends on cell history.

    PubMed

    van Eunen, K; Dool, P; Canelas, A B; Kiewiet, J; Bouwman, J; van Gulik, W M; Westerhoff, H V; Bakker, B M

    2010-03-01

    In this study, the authors investigated how the glycolytic flux was regulated in time upon nitrogen starvation of cells with different growth histories. We have compared cells grown in glucose-limited chemostat cultures under respiratory conditions (low dilution rate of 0.1/h) to cells grown under respirofermentative conditions (high dilution rate of 0.35/h). The fermentative capacity was lower in cells grown under respiratory conditions than in cells grown under respirofermentative conditions, yet more resilient to prolonged nitrogen starvation. The time profiles revealed that the fermentative capacity even increased in cells grown under respiratory conditions during the first hours of nitrogen starvation. In cells grown under respirofermentative conditions the fermentative capacity decreased from the onset of nitrogen starvation. We have applied time-dependent Regulation Analysis to follow the fermentative capacity during nitrogen starvation. In both experiments, diverse categories of regulation were found. However, in the cells grown under respiratory conditions regulation was predominantly metabolic, whereas in the cells grown under respirofermentative conditions hierarchical regulation was dominant. To study the metabolic regulation, concentrations of intracellular metabolites, including allosteric regulators, were measured. The obtained results can explain some aspects of the metabolic regulation, but not all.

  3. [Absinthe - history of dependence to thujone or to alcohol?].

    PubMed

    Lachenmeier, D W

    2007-05-01

    The etiopathology of absinthe dependence was previously attributed to the effects of the wormwood constituent thujone. Current research proves otherwise. Foremost, it must be considered that the wormwood plant shows a very large variance in quantity of thujone (0 - 70 % in essential oil) dependent on chemo type and cultivation area. Thus, absinthe does not contain thujone in general. Experimental production of absinthes and analyses of vintage absinthes (1900 - 1930) consistently showed that they contained only relatively low concentrations of thujone below today's maximum limits. Scientific literature contains no proof that historic absinthes may have contained thujone in concentrations able to produce toxic effects. The current state of research considers absinthism to be a type of alcoholism with thujone playing none or only a secondary role.

  4. Evolutionary history and distance dependence control survival of dipterocarp seedlings.

    PubMed

    Bagchi, Robert; Press, Malcolm C; Scholes, Julie D

    2010-01-01

    One important hypothesis to explain tree-species coexistence in tropical forests suggests that increased attack by natural enemies near conspecific trees gives locally rare species a competitive advantage. Host ranges of natural enemies generally encompass several closely related plant taxa suggesting that seedlings should also do poorly around adults of closely related species. We investigated the effects of adult Parashorea malaanonan on seedling survival in a Bornean rain forest. Survival of P. malaanonan seedlings was highest at intermediate distances from parent trees while heterospecific seedlings were unaffected by distance. Leaf herbivores did not drive this relationship. Survival of seedlings was lowest for P. malaanonan, and increased with phylogenetic dissimilarity from this species, suggesting that survival of close relatives of common species is reduced. This study suggests that distance dependence contributes to species coexistence and highlights the need for further investigation into the role of shared plant enemies in community dynamics.

  5. History dependent effects on phenotypic expression of a newly emerged gene.

    PubMed

    Suzuki, Takao; Kashiwagi, Akiko; Mori, Kotaro; Urabe, Itaru; Yomo, Tetsuya

    2004-11-01

    In this study, we investigate the history dependence of the penetrance of a newly emerged gene. Penetrance is defined as the percentage of individuals with a given genotype who exhibit the phenotype associated with that particular genotype. Here, we used the glutamine synthetase gene and its mutants with lower fitness as model genes. They were introduced into host cells of Escherichia coli deprived of the gene, and their penetrance was measured using the host having a different history: either with or without glutamine starvation. Results show that for all genes tested, the value of penetrance was higher when they were introduced into the host cell without starvation than that when introduced into the starved cell, demonstrating the history dependence of the penetrance of a newly emerged gene. In addition, genes with lower fitness showed lower penetrance, and the effect of the difference in fitness on gene penetrance also depended on the history of the host cell.

  6. Life history dependent morphometric variation in stream-dwelling Atlantic salmon

    USGS Publications Warehouse

    Letcher, B.H.

    2003-01-01

    The time course of morphometric variation among life histories for stream-dwelling Atlantic salmon (Salmo salar L.) parr (age-0+ to age-2+) was analyzed. Possible life histories were combinations of parr maturity status in the autumn (mature or immature) and age at outmigration (smolt at age-2+ or later age). Actual life histories expressed with enough fish for analysis in the 1997 cohort were immature/age-2+ smolt, mature/age-2 +smolt, and mature/age-2+ non-smolt. Tagged fish were assigned to one of the three life histories and digital pictures from the field were analyzed using landmark-based geometric morphometrics. Results indicated that successful grouping of fish according to life history varied with fish age, but that fish could be grouped before the actual expression of the life histories. By March (age-1+), fish were successfully grouped using a descriptive discriminant function and successful assignment ranged from 84 to 97% for the remainder of stream residence. A jackknife of the discriminant function revealed an average life history prediction success of 67% from age-1+ summer to smolting. Low sample numbers for one of the life histories may have limited prediction success. A MANOVA on the shape descriptors (relative warps) also indicated significant differences in shape among life histories from age-1+ summer through to smolting. Across all samples, shape varied significantly with size. Within samples, shape did not vary significantly with size for samples from December (age-0+) to May (age-1+). During the age-1+ summer however, shape varied significantly with size, but the relationship between shape and size was not different among life histories. In the autumn (age-1+) and winter (age-2+), life history differences explained a significant portion of the change in shape with size. Life history dependent morphometric variation may be useful to indicate the timing of early expressions of life history variation and as a tool to explore temporal and

  7. Ionic mechanisms underlying history-dependence of conduction delay in an unmyelinated axon.

    PubMed

    Zhang, Yang; Bucher, Dirk; Nadim, Farzan

    2017-07-10

    Axonal conduction velocity can change substantially during ongoing activity, thus modifying spike interval structures and, potentially, temporal coding. We used a biophysical model to unmask mechanisms underlying the history-dependence of conduction. The model replicates activity in the unmyelinated axon of the crustacean stomatogastric pyloric dilator neuron. At the timescale of a single burst, conduction delay has a non-monotonic relationship with instantaneous frequency, which depends on the gating rates of the fast voltage-gated Na(+) current. At the slower timescale of minutes, the mean value and variability of conduction delay increase. These effects are because of hyperpolarization of the baseline membrane potential by the Na(+)/K(+) pump, balanced by an h-current, both of which affect the gating of the Na(+) current. We explore the mechanisms of history-dependence of conduction delay in axons and develop an empirical equation that accurately predicts this history-dependence, both in the model and in experimental measurements.

  8. Combined role of childhood maltreatment, family history, and gender in the risk for alcohol dependence

    PubMed Central

    Fenton, M. C.; Geier, T.; Keyes, K.; Skodol, A. E.; Grant, B. F.; Hasin, D. S.

    2013-01-01

    Background Studies of the relationship between childhood maltreatment and alcohol dependence have not controlled comprehensively for potential confounding by co-occurring maltreatments and other childhood trauma, or determined whether parental history of alcohol disorders operates synergistically with gender and maltreatment to produce alcohol dependence. We addressed these issues using national data. Method Face-to-face surveys of 27 712 adult participants in a national survey. Results Childhood physical, emotional and sexual abuse, and physical neglect were associated with alcohol dependence (p<0.001), controlling for demographics, co-occurring maltreatments and other childhood trauma. Attributable proportions (APs) due to interaction between each maltreatment and parental history revealed significant synergistic relationships for physical abuse in the entire sample, and for sexual abuse and emotional neglect in women (APs, 0.21, 0.31, 0.26 respectively), indicating that the odds of alcohol dependence given both parental history and these maltreatments were significantly higher than the additive effect of each alone (p<0.05). Conclusions Childhood maltreatments independently increased the risk of alcohol dependence. Importantly, results suggest a synergistic role of parental alcoholism: the effect of physical abuse on alcohol dependence may depend on parental history, while the effects of sexual abuse and emotional neglect may depend on parental history among women. Findings underscore the importance of early identification and prevention, particularly among those with a family history, and could guide genetic research and intervention development, e.g. programs to reduce the burden of childhood maltreatment may benefit from addressing the negative long-term effects of maltreatments, including potential alcohol problems, across a broad range of childhood environments. PMID:22883538

  9. Nicotine withdrawal and dependence among smokers with a history of childhood abuse.

    PubMed

    Smith, Philip H; Homish, Gregory G; Saddleson, Megan L; Kozlowski, Lynn T; Giovino, Gary A

    2013-12-01

    Previous studies have found that those with a history of childhood abuse are more likely to smoke cigarettes than those without a history of abuse. Mechanisms underlying this greater prevalence are unclear. We examined whether current smokers with a history of childhood abuse reported greater levels of nicotine dependence and more severe nicotine withdrawal symptoms. We analyzed data from a 2-wave, national, random-digit-dial survey of adult cigarette smokers (n = 751). We examined whether childhood physical, emotional, and sexual abuse were associated with greater levels of nicotine dependence. Among those who made a quit attempt (n = 368), we examined whether abuse was associated with more severe withdrawal symptoms recalled during the 14 months between surveys. For both dependence and withdrawal, we tested a mediation pathway through current serious mental illness (SMI). All 3 types of childhood abuse were associated with more severe withdrawal symptoms. These associations were partially mediated by SMI. Sexual abuse and physical abuse were directly associated with dependence, whereas emotional abuse was indirectly associated with dependence through SMI. All 3 forms of childhood abuse were associated with both dependence and withdrawal. The greater prevalence of smoking found among those with a history of childhood abuse may be explained by heightened vulnerability to nicotine dependence and withdrawal and may be partially due to comorbid mental illness.

  10. History-Dependent Problems with Applications to Contact Models for Elastic Beams

    SciTech Connect

    Bartosz, Krzysztof; Kalita, Piotr; Migórski, Stanisław; Ochal, Anna; Sofonea, Mircea

    2016-02-15

    We prove an existence and uniqueness result for a class of subdifferential inclusions which involve a history-dependent operator. Then we specialize this result in the study of a class of history-dependent hemivariational inequalities. Problems of such kind arise in a large number of mathematical models which describe quasistatic processes of contact. To provide an example we consider an elastic beam in contact with a reactive obstacle. The contact is modeled with a new and nonstandard condition which involves both the subdifferential of a nonconvex and nonsmooth function and a Volterra-type integral term. We derive a variational formulation of the problem which is in the form of a history-dependent hemivariational inequality for the displacement field. Then, we use our abstract result to prove its unique weak solvability. Finally, we consider a numerical approximation of the model, solve effectively the approximate problems and provide numerical simulations.

  11. Evolution of male life histories and age-dependent sexual signals under female choice

    PubMed Central

    2013-01-01

    Sexual selection theory models evolution of sexual signals and preferences using simple life histories. However, life-history models predict that males benefit from increasing sexual investment approaching old age, producing age-dependent sexual traits. Age-dependent traits require time and energy to grow, and will not fully mature before individuals enter mating competition. Early evolutionary stages pose several problems for these traits. Age-dependent traits suffer from strong viability selection and gain little benefit from mate choice when rare. Few males will grow large traits, and they will rarely encounter choosy females. The evolutionary origins of age-dependent traits therefore remain unclear. I used numerical simulations to analyze evolution of preferences, condition (viability) and traits in an age-structured population. Traits in the model depended on age and condition (“good genes”) in a population with no genetic drift. I asked (1) if age-dependent indicator traits and their preferences can originate depending on the strength of selection and the size of the trait; (2) which mode of development (age-dependent versus age-independent) eventually predominates when both modes occur in the population; and (3) if age-independent traits can invade a population with age-dependent traits. Age-dependent traits evolve under weaker selection and at smaller sizes than age-independent traits. This result held in isolation and when the types co-occur. Evolution of age-independent traits depends only on trait size, whereas evolution of age-dependent traits depends on both strength of selection and growth rate. Invasion of age-independence into populations with established traits followed a similar pattern with age-dependence predominating at small trait sizes. I suggest that reduced adult mortality facilitates sexual selection by favoring the evolution of age-dependent sexual signals under weak selection. PMID:24392289

  12. Enhanced intensity dependence and aggression history indicate previous regular ecstasy use in abstinent polydrug users.

    PubMed

    Wan, Li; Baldridge, Robyn M; Colby, Amanda M; Stanford, Matthew S

    2009-11-13

    Intensity dependence is an electrophysiological measure of intra-individual stability of the augmenting/reducing characteristic of N1/ P2 event-related potential amplitudes in response to stimuli of varying intensities. Abstinent ecstasy users typically show enhanced intensity dependence and higher levels of impulsivity and aggression. Enhanced intensity dependence and high impulsivity and aggression levels may be due to damage in the brain's serotonergic neurons as a result of ecstasy use. The present study investigated whether intensity dependence, impulsivity and aggression history can be used as indicators of previous chronic ecstasy usage. Forty-four abstinent polydrug users (8 women; age 19 to 61 years old) were recruited. All participants were currently residents at a local substance abuse facility receiving treatment and had been free of all drugs for a minimum of 21 days. The study found significantly enhanced intensity dependence of tangential dipole source activity and a history of more aggressive behavior in those who had previously been involved in chronic ecstasy use. Intensity dependence of the tangential dipole source and aggressive behavior history correctly identified 73.3% of those who had been regular ecstasy users and 78.3% of those who had not. Overall, 76.3% of the participants were correctly classified.

  13. Thermomagnetic history dependence of magnetocaloric effect in Ni50Mn34In16

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, M. K.; Sharma, V. K.; Roy, S. B.

    2008-01-01

    A large inverse magnetocaloric effect has been reported to be associated with the austenite to martensite phase transition in Ni50Mn34In16. It is shown here that the magnitude of the observed magnetocaloric effect as well as effective refrigerant capacity depend significantly on the thermo-magnetic history of the sample.

  14. History-dependent friction and slow slip from time-dependent microscopic junction laws studied in a statistical framework.

    PubMed

    Thøgersen, Kjetil; Trømborg, Jørgen Kjoshagen; Sveinsson, Henrik Andersen; Malthe-Sørenssen, Anders; Scheibert, Julien

    2014-05-01

    To study how macroscopic friction phenomena originate from microscopic junction laws, we introduce a general statistical framework describing the collective behavior of a large number of individual microjunctions forming a macroscopic frictional interface. Each microjunction can switch in time between two states: a pinned state characterized by a displacement-dependent force and a slipping state characterized by a time-dependent force. Instead of tracking each microjunction individually, the state of the interface is described by two coupled distributions for (i) the stretching of pinned junctions and (ii) the time spent in the slipping state. This framework allows for a whole family of microjunction behavior laws, and we show how it represents an overarching structure for many existing models found in the friction literature. We then use this framework to pinpoint the effects of the time scale that controls the duration of the slipping state. First, we show that the model reproduces a series of friction phenomena already observed experimentally. The macroscopic steady-state friction force is velocity dependent, either monotonic (strengthening or weakening) or nonmonotonic (weakening-strengthening), depending on the microscopic behavior of individual junctions. In addition, slow slip, which has been reported in a wide variety of systems, spontaneously occurs in the model if the friction contribution from junctions in the slipping state is time weakening. Next, we show that the model predicts a nontrivial history dependence of the macroscopic static friction force. In particular, the static friction coefficient at the onset of sliding is shown to increase with increasing deceleration during the final phases of the preceding sliding event. We suggest that this form of history dependence of static friction should be investigated in experiments, and we provide the acceleration range in which this effect is expected to be experimentally observable.

  15. A nonlinear history-dependent damage model for low cycle fatigue

    NASA Technical Reports Server (NTRS)

    Leis, B. N.

    1988-01-01

    A nonlinear damage postulate that embodies the dependence of the damage rate on cycle-dependent changes in the bulk microstructure and the surface topography is examined. The postulate is analytically formulated in terms of the deformation history dependence of the bulk behavior. This formulation is used in conjunction with baseline data in accordance with the damage postulate to predict the low cycle fatigue resistance of OFE copper. Close comparison of the predictions with experimentally observed behavior suggests that the postulate offers a viable basis for nonlinear damage analysis.

  16. A nonlinear history-dependent damage model for low cycle fatigue

    NASA Technical Reports Server (NTRS)

    Leis, B. N.

    1988-01-01

    A nonlinear damage postulate that embodies the dependence of the damage rate on cycle-dependent changes in the bulk microstructure and the surface topography is examined. The postulate is analytically formulated in terms of the deformation history dependence of the bulk behavior. This formulation is used in conjunction with baseline data in accordance with the damage postulate to predict the low cycle fatigue resistance of OFE copper. Close comparison of the predictions with experimentally observed behavior suggests that the postulate offers a viable basis for nonlinear damage analysis.

  17. Ionic mechanisms underlying history-dependence of conduction delay in an unmyelinated axon

    PubMed Central

    Zhang, Yang; Bucher, Dirk; Nadim, Farzan

    2017-01-01

    Axonal conduction velocity can change substantially during ongoing activity, thus modifying spike interval structures and, potentially, temporal coding. We used a biophysical model to unmask mechanisms underlying the history-dependence of conduction. The model replicates activity in the unmyelinated axon of the crustacean stomatogastric pyloric dilator neuron. At the timescale of a single burst, conduction delay has a non-monotonic relationship with instantaneous frequency, which depends on the gating rates of the fast voltage-gated Na+ current. At the slower timescale of minutes, the mean value and variability of conduction delay increase. These effects are because of hyperpolarization of the baseline membrane potential by the Na+/K+ pump, balanced by an h-current, both of which affect the gating of the Na+ current. We explore the mechanisms of history-dependence of conduction delay in axons and develop an empirical equation that accurately predicts this history-dependence, both in the model and in experimental measurements. DOI: http://dx.doi.org/10.7554/eLife.25382.001 PMID:28691900

  18. Correcting the initialization of models with fractional derivatives via history-dependent conditions

    NASA Astrophysics Data System (ADS)

    Du, Maolin; Wang, Zaihua

    2016-04-01

    Fractional differential equations are more and more used in modeling memory (history-dependent, non-local, or hereditary) phenomena. Conventional initial values of fractional differential equations are defined at a point, while recent works define initial conditions over histories. We prove that the conventional initialization of fractional differential equations with a Riemann-Liouville derivative is wrong with a simple counter-example. The initial values were assumed to be arbitrarily given for a typical fractional differential equation, but we find one of these values can only be zero. We show that fractional differential equations are of infinite dimensions, and the initial conditions, initial histories, are defined as functions over intervals. We obtain the equivalent integral equation for Caputo case. With a simple fractional model of materials, we illustrate that the recovery behavior is correct with the initial creep history, but is wrong with initial values at the starting point of the recovery. We demonstrate the application of initial history by solving a forced fractional Lorenz system numerically.

  19. Quantifying the history dependency of muscle recovery from a fatiguing intermittent task.

    PubMed

    Rashedi, Ehsan; Nussbaum, Maury A

    2017-01-25

    Muscle fatigue and recovery are complex processes influencing muscle force generation capacity. While fatigue reduces this capacity, recovery acts to restore the unfatigued muscle state. Many factors can potentially affect muscle recovery, and among these may be a task dependency of recovery following an exercise. However, little has been reported regarding the history dependency of recovery after fatiguing contractions. We examined the dependency of muscle recovery subsequent to four different histories of fatiguing muscle contractions, imposed using two cycle times (30 and 60s) during low to moderate levels (15% and 25% of maximum voluntary contraction (MVC)) of intermittent static exertions involving index finger abduction. MVC and low-frequency electrical stimulation (LFES) measures (i.e., magnitude, rise and relaxation rates) of muscle capacity were used, all of which indicated a dependency of muscle recovery on the muscle capacity state existing immediately after fatiguing exercise. This dependency did not appear to be modified by either the cycle time or exertion level leading to that state. These results imply that the post-exercise rate of recovery is primarily influenced by the immediate post-exercise muscle contractile status (estimated by MVC and LFES measures). Such results may help improve existing models of muscle recovery, facilitating more accurate predictions of localized muscle fatigue development and thereby helping to enhance muscle performance and reduce the risk of injury.

  20. Computational studies of history dependence in nematic liquid crystals in random environments

    NASA Astrophysics Data System (ADS)

    Ranjkesh, Amid; Ambrožič, Milan; Kralj, Samo; Sluckin, Timothy J.

    2014-02-01

    Glassy liquid crystalline systems are expected to show significant history-dependent effects. Two model glassy systems are the RAN and SSS (sprinkled silica spin) lattice models. The RAN model is a Lebwohl-Lasher lattice model with locally coupled nematic spins, together with uncorrelated random anisotropy fields at each site, while the SSS model has a finite concentration of impurity spins frozen in random directions. Here Brownian simulation is used to study the effect of different sample histories in the low temperature regime in a three-dimensional (d =3) model intermediate between SSS and RAN, in which a finite concentration p histories (TQH and FQH, respectively), as well as for temperature-annealed histories (AH). The first two of these limits represent extreme histories encountered in typical experimental studies. Using long-time averages for equilibrated systems, we calculate orientational order parameters and two-point correlation functions. Finite-size scaling was used to determine the range of the orientational ordering, as a function of coupling strength W ,p and sample history. Sample history plays a significant role; for given concentration p, as disorder strength W is increased, TQH systems sustain quasi-long-range order (QLRO) and short-range order (SRO). The data are also consistent with a long-range order (LRO) phase at very low disorder strength. By contrast, for FQH and p ≤0.1, only LRO and QLRO occur within the range of parameters investigated. The crossover between regimes depends on history, but in general, the FQH phase is more ordered than the AH phase, which is more ordered than the TQH phase. However, at temperatures close to the isotropic-nematic phase transition of pure samples

  1. Memory in microbes: quantifying history-Dependent behavior in a bacterium.

    SciTech Connect

    Wolf, Denise M.; Fontaine-Bodin, Lisa; Bischofs, Ilka; Price, Gavin; Keaslin, Jay; Arkin, Adam P.

    2007-11-15

    Memory is usually associated with higher organisms rather than bacteria. However, evidence is mounting that many regulatory networks within bacteria are capable of complex dynamics and multi-stable behaviors that have been linked to memory in other systems. Moreover, it is recognized that bacteria that have experienced different environmental histories may respond differently to current conditions. These"memory" effects may be more than incidental to the regulatory mechanisms controlling acclimation or to the status of the metabolic stores. Rather, they may be regulated by the cell and confer fitness to the organism in the evolutionary game it participates in. Here, we propose that history-dependent behavior is a potentially important manifestation of memory, worth classifying and quantifying. To this end, we develop an information-theory based conceptual framework for measuring both the persistence of memory in microbes and the amount of information about the past encoded in history-dependent dynamics. This method produces a phenomenological measure of cellular memory without regard to the specific cellular mechanisms encoding it. We then apply this framework to a strain of Bacillus subtilis engineered to report on commitment to sporulation and degradative enzyme (AprE) synthesis and estimate the capacity of these systems and growth dynamics to 'remember' 10 distinct cell histories prior to application of a common stressor. The analysis suggests that B. subtilis remembers, both in short and long term, aspects of its cell history, and that this memory is distributed differently among the observables. While this study does not examine the mechanistic bases for memory, it presents a framework for quantifying memory in cellular behaviors and is thus a starting point for studying new questions about cellular regulation and evolutionary strategy.

  2. History-Dependent Excitability as a Single-Cell Substrate of Transient Memory for Information Discrimination

    PubMed Central

    Baroni, Fabiano; Torres, Joaquín J.; Varona, Pablo

    2010-01-01

    Neurons react differently to incoming stimuli depending upon their previous history of stimulation. This property can be considered as a single-cell substrate for transient memory, or context-dependent information processing: depending upon the current context that the neuron “sees” through the subset of the network impinging on it in the immediate past, the same synaptic event can evoke a postsynaptic spike or just a subthreshold depolarization. We propose a formal definition of History-Dependent Excitability (HDE) as a measure of the propensity to firing in any moment in time, linking the subthreshold history-dependent dynamics with spike generation. This definition allows the quantitative assessment of the intrinsic memory for different single-neuron dynamics and input statistics. We illustrate the concept of HDE by considering two general dynamical mechanisms: the passive behavior of an Integrate and Fire (IF) neuron, and the inductive behavior of a Generalized Integrate and Fire (GIF) neuron with subthreshold damped oscillations. This framework allows us to characterize the sensitivity of different model neurons to the detailed temporal structure of incoming stimuli. While a neuron with intrinsic oscillations discriminates equally well between input trains with the same or different frequency, a passive neuron discriminates better between inputs with different frequencies. This suggests that passive neurons are better suited to rate-based computation, while neurons with subthreshold oscillations are advantageous in a temporal coding scheme. We also address the influence of intrinsic properties in single-cell processing as a function of input statistics, and show that intrinsic oscillations enhance discrimination sensitivity at high input rates. Finally, we discuss how the recognition of these cell-specific discrimination properties might further our understanding of neuronal network computations and their relationships to the distribution and functional

  3. Former heroin addicts with or without a history of cocaine dependence are more impulsive than controls.

    PubMed

    Nielsen, David A; Ho, Ann; Bahl, Ajay; Varma, Priya; Kellogg, Scott; Borg, Lisa; Kreek, Mary Jeanne

    2012-07-01

    Personality traits such as impulsivity and sensation seeking may contribute to the initiation and maintenance of illicit drug use. Since studies have reported higher impulsivity and sensation seeking traits in cocaine dependent subjects, we were interested in determining whether former heroin addicts in methadone pharmacotherapy with comorbid cocaine addiction have greater impulsivity than those without. Instruments to assess impulsivity (Barratt Impulsiveness Scale version 11) and sensation seeking (Sensation Seeking Scale version V) were administered to former severe heroin addicts meeting Federal criteria for methadone maintenance pharmacotherapy with (n = 71) or without cocaine dependence (n = 31) and to 145 normal healthy (non-methadone-maintained) volunteers. The methadone-maintained without cocaine dependence and the methadone-maintained with cocaine dependence groups, both scored higher than did the normal volunteer group on the Barratt Impulsiveness Scale total score (p<0.001). On the Barratt Impulsiveness Scale Attentional, Nonplanning, and Motor subscales, the methadone-maintained and methadone-maintained with cocaine dependence groups scored higher than did normal volunteers with no history of drug abuse or dependence (p<0.001). There was no difference among groups on total score or any subscale of the Sensation Seeking Scale. However, males in all groups overall scored higher than did females on Disinhibition and Thrill and Adventure seeking subscales of the Sensation Seeking Scale version V (p<0.001). This study demonstrates higher impulsivity in former severe heroin addicts meeting criteria for or currently in stable methadone maintenance pharmacotherapy, irrespective of a positive or negative history of cocaine dependence. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  4. Former Heroin Addicts with or without a History of Cocaine Dependence are more Impulsive than Controls

    PubMed Central

    Nielsen, David A.; Ho, Ann; Bahl, Ajay; Varma, Priya; Kellogg, Scott; Borg, Lisa; Kreek, Mary Jeanne

    2012-01-01

    Background Personality traits such as impulsivity and sensation seeking may contribute to the initiation and maintenance of illicit drug use. Since studies have reported higher impulsivity and sensation seeking traits in cocaine dependent subjects, we were interested in determining whether former heroin addicts in methadone pharmacotherapy with comorbid cocaine addiction have greater impulsivity than those without. Methods Instruments to assess impulsivity (Barratt Impulsiveness Scale version 11) and sensation seeking (Sensation Seeking Scale version V) were administered to former severe heroin addicts meeting Federal criteria for methadone maintenance pharmacotherapy with (n = 71) or without cocaine dependence (n = 31) and to 145 normal healthy (non-methadone-maintained) volunteers. Results The methadone-maintained without cocaine dependence and the methadone-maintained with cocaine dependence groups, both scored higher than did the normal volunteer group on the Barratt Impulsiveness Scale total score (p < 0.001). On the Barratt Impulsiveness Scale Attentional, Nonplanning, and Motor subscales, the methadone-maintained and methadone-maintained with cocaine dependence groups scored higher than did normal volunteers with no history of drug abuse or dependence (p < 0.001). There was no difference among groups on total score or any subscale of the Sensation Seeking Scale. However, males in all groups overall scored higher than did females on Disinhibition and Thrill and Adventure seeking subscales of the Sensation Seeking Scale version V (p < 0.001). Conclusions This study demonstrates higher impulsivity in former severe heroin addicts meeting criteria for or currently in stable methadone maintenance pharmacotherapy, irrespective of a positive or negative history of cocaine dependence. PMID:22265192

  5. Density-dependent life history and the dynamics of small populations.

    PubMed

    Mugabo, Marianne; Perret, Samuel; Legendre, Stéphane; Le Galliard, Jean-François

    2013-11-01

    1. Small population dynamics depend importantly on the strength and shape of density dependence. Unfortunately, the lack of reliable life-history data often prevents to make accurate demographic predictions for populations regulated by density dependence. 2. We created a gradient from low to high densities in small experimental populations of common lizards (Zootoca vivipara) and investigated the shape and strength of the density dependence of life-history traits during a yearly cycle. We then analysed stochastic population dynamics using one-sex and two-sex age-structured matrix models. 3. Body growth and reproductive performances decreased with density, yearling and adult survival and body size at birth were density-independent, and juvenile survival increased with density. The density dependence of reproduction was partly explained by positive effects of body size on age at first reproduction and clutch size. 4. Parturition date decreased with density in sparse populations and then increased, providing one of the first empirical evidence of a component Allee effect in the phenology of reproduction. 5. Population growth rate (λ) was most affected by variations in juvenile and yearling survival. However, density at equilibrium was most affected by juvenile access to reproduction and yearling clutch size. 6. Stochastic simulations revealed that negative density dependence buffers the effects of initial density on extinction probability, has positive effects on the persistence of sparse populations and interacts with sex ratio fluctuations to shape extinction dynamics. 7. This study demonstrates that negative density dependence modifies the dynamics of small populations and should be investigated together with Allee effects to predict extinction risks. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

  6. Environmental History Modulates Arabidopsis Pattern-Triggered Immunity in a HISTONE ACETYLTRANSFERASE1-Dependent Manner.

    PubMed

    Singh, Prashant; Yekondi, Shweta; Chen, Po-Wen; Tsai, Chia-Hong; Yu, Chun-Wei; Wu, Keqiang; Zimmerli, Laurent

    2014-06-01

    In nature, plants are exposed to a fluctuating environment, and individuals exposed to contrasting environmental factors develop different environmental histories. Whether different environmental histories alter plant responses to a current stress remains elusive. Here, we show that environmental history modulates the plant response to microbial pathogens. Arabidopsis thaliana plants exposed to repetitive heat, cold, or salt stress were more resistant to virulent bacteria than Arabidopsis grown in a more stable environment. By contrast, long-term exposure to heat, cold, or exposure to high concentrations of NaCl did not provide enhanced protection against bacteria. Enhanced resistance occurred with priming of Arabidopsis pattern-triggered immunity (PTI)-responsive genes and the potentiation of PTI-mediated callose deposition. In repetitively stress-challenged Arabidopsis, PTI-responsive genes showed enrichment for epigenetic marks associated with transcriptional activation. Upon bacterial infection, enrichment of RNA polymerase II at primed PTI marker genes was observed in environmentally challenged Arabidopsis. Finally, repetitively stress-challenged histone acetyltransferase1-1 (hac1-1) mutants failed to demonstrate enhanced resistance to bacteria, priming of PTI, and increased open chromatin states. These findings reveal that environmental history shapes the plant response to bacteria through the development of a HAC1-dependent epigenetic mark characteristic of a primed PTI response, demonstrating a mechanistic link between the primed state in plants and epigenetics.

  7. History dependence of human muscle-fiber conduction velocity during voluntary isometric contractions

    PubMed Central

    Lateva, Zoia C.

    2011-01-01

    The conduction velocity (CV) of a muscle fiber is affected by the fiber's discharge history going back ∼1 s. We investigated this dependence by measuring CV fluctuations during voluntary isometric contractions of the human brachioradialis muscle. We recorded electromyogram (EMG) signals simultaneously from multiple intramuscular electrodes, identified potentials belonging to the same motor unit using EMG decomposition, and estimated the CV of each discharge from the interpotential interval. In 12 of 14 subjects, CV increased by ∼10% during the first second after recruitment and then fluctuated by about ±2% in a way that mirrored the fluctuations in the instantaneous firing rate. The CV profile could be precisely described in terms of the discharge history by a simple mathematical model. In the other two subjects, and one subject retested after cooling the arm, the CV fluctuations were inversely correlated with instantaneous firing rate. In all subjects, CV was additionally affected by very short interdischarge intervals (<25 ms): it was increased in doublets at recruitment, but decreased in doublets during continuous firing and after short interdischarge intervals in doubly innervated fibers. CV also exhibited a slow trend of about −0.05%/s that did not depend on the immediate discharge history. We suggest that measurements of CV fluctuations during voluntary contractions, or during stimulation protocols that involve longer and more complex stimulation patterns than are currently being used, may provide a sensitive approach for estimating the dynamic characteristics of ion channels in the human muscle-fiber membrane. PMID:21565985

  8. Memory in Microbes: Quantifying History-Dependent Behavior in a Bacterium

    SciTech Connect

    Wolf, Denise M.; Fontaine-Bodin, Lisa; Bischofs, Ilka; Price, Gavin; Keasling, Jay; Arkin, Adam P.

    2007-11-15

    Memory is usually associated with higher organisms rather than bacteria. However, evidence is mounting that many regulatory networks within bacteria are capable of complex dynamics and multi-stable behaviors that have been linked to memory in other systems. Moreover, it is recognized that bacteria that have experienced different environmental histories may respond differently to current conditions. These"memory" effects may be more than incidental to the regulatory mechanisms controlling acclimation or to the status of the metabolic stores. Rather, they may be regulated by the cell and confer fitness to the organism in the evolutionary game it participates in. Here, we propose that history-dependent behavior is a potentially important manifestation of memory, worth classifying and quantifying. To this end, we develop an information-theory based conceptual framework for measuring both the persistence of memory in microbes and the amount of information about the past encoded in history-dependent dynamics. This method produces a phenomenologicalmeasure of cellular memory without regard to the specific cellular mechanisms encoding it. We then apply this framework to a strain of Bacillus subtilis engineered to report on commitment to sporulation and degradative enzyme (AprE) synthesisand estimate the capacity of these systems and growth dynamics to"remember" 10 distinct cell histories prior to application of a common stressor. The analysis suggests that B. subtilis remembers, both in short and long term, aspects of its cellhistory, and that this memory is distributed differently among the observables. While this study does not examine the mechanistic bases for memory, it presents a framework for quantifying memory in cellular behaviors and is thus a starting point for studying new questions about cellular regulation and evolutionary strategy.

  9. Critical current characteristics and history dependence in superconducting SmFeAsOF bulk

    NASA Astrophysics Data System (ADS)

    Ni, B.; Ge, J.; Kiuchi, M.; Otabe, E. S.; Gao, Z.; Wang, L.; Qi, Y.; Zhang, X.; Ma, Y.

    2010-06-01

    The superconducting SmFeAsO1-xFx (x=0.2) polycrystalline bulks were prepared by the powder-in-tube (PIT) method. The magnetic field and temperature dependences of critical current densities in the samples were investigated by resistive and ac inductive (Campbell's) methods. It was found that a fairly large shielding current density over 109 A/m2, which is considered to correspond to the local critical current density, flows locally with the perimeter size similar to the average grain size of the bulk samples, while an extremely low transport current density of about 105 A/m2 corresponding to the global critical current density flows through the whole sample. Furthermore, a unique history dependence of global critical current density was observed, i.e., it shows a smaller value in the increasing-field process than that in the decreasing-field process. The history dependence of global critical current characteristic in our case can be ascribed to the existence of the weak-link property between the grains in SmFeAsO1-xFx bulk.

  10. History-dependent changes in entrainment of the activity rhythm in the Syrian hamster (Mesocricetus auratus).

    PubMed

    Chiesa, Juan J; Anglès-Pujolràs, Montserrat; Díez-Noguera, Antoni; Cambras, Trinitat

    2006-02-01

    The authors have studied the activity rhythm of Syrian hamsters exposed to square LD cycles with a 22-h period (T22) with the aim of testing the effects of the previous history on the rhythmic pattern. To do so, sequential changes of different lighting environments were established, followed by the same LD condition. Also, the protocol included T22 cycles with varying lighting contrasts to test the extent to which a computational model predicts experimental outcomes. At the beginning of the experiment, exposure to T22 with 300 lux and dim red light occurring respectively at photophase and scotophase (LD300/dim red) mainly generated relative coordination. Subsequent transfer to cycles with approximately 0.1-lux dim light during the scotophase (LD300/0.1) promoted entrainment to T22. However, a further reduction in light intensity to 10 lux during the photophase (LD10/0.1) generated weak and unstable T22 rhythms. When, after that, animals were transferred again to the initial LD300/dim red cycles, the amplitude of the rhythm still remained very low, and the phases were very unstable. Exposure to constant darkness partially restored the activity rhythm, and when, afterwards, the animals were submitted again to LD300/dim red cycles, a robust T22 rhythm appeared. The results demonstrate history-dependent changes in the hamster circadian system because the locomotor activity pattern under the same T22 cycle can show relative coordination or unstable or robust entrainment depending on the prior lighting condition. This suggests that the circadian system responds to environmental stimuli depending on its previous history. Moreover, computer simulations allow the authors to predict entrainment under LD300/0.1 cycles and indicate that most of the patterns observed in the animals due to the light in the scotophase can be explained by different degrees of coupling among the oscillators of the circadian system.

  11. History Dependent Magnetoresistance in Lightly Doped LaZxSrxCuO4Thin Films

    SciTech Connect

    Bozovic I.; Shi, X.; Popovic, D.; Panagopoulos, C.; Logvenov, G.; Bollinger, A.T.

    2012-06-01

    The in-plane magnetoresistance (MR) in atomically smooth La{sub 2-x}Sr{sub x}CuO{sub 4} thin films grown by molecular-beam-epitaxy was measured in magnetic fields B up to 9 T over a wide range of temperatures T. The films, with x = 0.03 and x = 0.05, are insulating, and the positive MR emerges at T < 4 K. The positive MR exhibits glassy features, including history dependence and memory, for all orientations of B. The results show that this behavior, which reflects the onset of glassiness in the dynamics of doped holes, is a robust feature of the insulating state.

  12. History of sexual, emotional or physical abuse and psychiatric comorbidity in substance-dependent patients.

    PubMed

    Daigre, Constanza; Rodríguez-Cintas, Laia; Tarifa, Núria; Rodríguez-Martos, Lola; Grau-López, Lara; Berenguer, Marta; Casas, Miguel; Roncero, Carlos

    2015-10-30

    Sexual, emotional or physical abuse history is a risk factor for mental disorders in addicted patients. However, the relationship between addiction and abuse lifespan is not well known. This study aims to compare clinical and psychopathological features of addicted patients according to the experience of abuse and to the number of different types of abuse suffered. Bivariate and multivariate analyses were conducted. 512 addicted patients seeking treatment were included, 45.9% reported abuse throughout life (38.9% emotional, 22.3% physical and 13.5% sexual abuse). It was found that female gender; depressive symptoms and borderline personality disorder were independently associated with history of any abuse throughout life. As well, it was found that 14% have been suffered from all three types of abuse (sexual, emotional and physical), 34.5% from two and 55.5% from one type. Female gender and borderline personality disorder were independently associated independently with a greater number of different types of abuse. Results suggest that history of abuse is frequent among substance-dependent patients and these experiences are more prevalent in women and are associated with more psychiatric comorbidity.

  13. Density-dependent coral recruitment displays divergent responses during distinct early life-history stages

    PubMed Central

    Evensen, Nicolas R.; Gómez-Lemos, Luis A.; Babcock, Russell C.

    2017-01-01

    Population growth involves demographic bottlenecks that regulate recruitment success during various early life-history stages. The success of each early life-history stage can vary in response to population density, interacting with intrinsic (e.g. behavioural) and environmental (e.g. competition, predation) factors. Here, we used the common reef-building coral Acropora millepora to investigate how density-dependence influences larval survival and settlement in laboratory experiments that isolated intrinsic effects, and post-settlement survival in a field experiment that examined interactions with environmental factors. Larval survival was exceptionally high (greater than 80%) and density-independent from 2.5 to 12 days following spawning. By contrast, there was a weak positive effect of larval density on settlement, driven by gregarious behaviour at the highest density. When larval supply was saturated, settlement was three times higher in crevices compared with exposed microhabitats, but a negative relationship between settler density and post-settlement survival in crevices and density-independent survival on exposed surfaces resulted in similar recruit densities just one month following settlement. Moreover, a negative relationship was found between turf algae and settler survival in crevices, whereas gregarious settlement improved settler survival on exposed surfaces. Overall, our findings reveal divergent responses by coral larvae and newly settled recruits to density-dependent regulation, mediated by intrinsic and environmental interactions. PMID:28573015

  14. Life history evolution, reproduction, and the origins of sex-dependent aging and longevity.

    PubMed

    Brooks, Robert C; Garratt, Michael G

    2017-02-01

    Males and females in many species differ in how they age and how long they live. These differences have motivated much research, concerning both their evolution and the underlying mechanisms that cause them. We review how differences in male and female life histories have evolved to shape patterns of aging and some of the mechanisms and pathways involved. We pay particular attention to three areas where considerable potential for synergy between mechanistic and evolutionary research exists: (1) the role of estrogens, androgens, the growth hormone/insulin-like growth factor 1 pathway, and the mechanistic target of rapamycin signaling pathway in sex-dependent growth and reproduction; (2) sexual conflict over mating rate and fertility, and how mate presence or mating can become an avenue for males and females to directly affect each other's life span; and (3) the link between dietary restriction and aging, and the emerging understanding that only the restriction of certain nutrients is involved and that this is linked to reproduction. We suggest that ideas about life histories, sex-dependent selection, and sexual conflict can inform and be informed by the ever more refined and complex understanding of the mechanisms that cause aging. © 2016 New York Academy of Sciences.

  15. Density-dependent coral recruitment displays divergent responses during distinct early life-history stages.

    PubMed

    Doropoulos, Christopher; Evensen, Nicolas R; Gómez-Lemos, Luis A; Babcock, Russell C

    2017-05-01

    Population growth involves demographic bottlenecks that regulate recruitment success during various early life-history stages. The success of each early life-history stage can vary in response to population density, interacting with intrinsic (e.g. behavioural) and environmental (e.g. competition, predation) factors. Here, we used the common reef-building coral Acropora millepora to investigate how density-dependence influences larval survival and settlement in laboratory experiments that isolated intrinsic effects, and post-settlement survival in a field experiment that examined interactions with environmental factors. Larval survival was exceptionally high (greater than 80%) and density-independent from 2.5 to 12 days following spawning. By contrast, there was a weak positive effect of larval density on settlement, driven by gregarious behaviour at the highest density. When larval supply was saturated, settlement was three times higher in crevices compared with exposed microhabitats, but a negative relationship between settler density and post-settlement survival in crevices and density-independent survival on exposed surfaces resulted in similar recruit densities just one month following settlement. Moreover, a negative relationship was found between turf algae and settler survival in crevices, whereas gregarious settlement improved settler survival on exposed surfaces. Overall, our findings reveal divergent responses by coral larvae and newly settled recruits to density-dependent regulation, mediated by intrinsic and environmental interactions.

  16. Nonadjacent Dependency Learning in Cantonese-Speaking Children with and without a History of Specific Language Impairment

    ERIC Educational Resources Information Center

    Iao, Lai-Sang; Ng, Lai Yan; Wong, Anita Mei Yin; Lee, Oi Ting

    2017-01-01

    Purpose: This study investigated nonadjacent dependency learning in Cantonese-speaking children with and without a history of specific language impairment (SLI) in an artificial linguistic context. Method: Sixteen Cantonese-speaking children with a history of SLI and 16 Cantonese-speaking children with typical language development (TLD) were…

  17. Childhood or Adolescent Parental Divorce/Separation, Parental History of Alcohol Problems, and Offspring Lifetime Alcohol Dependence

    PubMed Central

    Thompson, Ronald G.; Lizardi, Dana; Keyes, Katherine M.; Hasin, Deborah S.

    2013-01-01

    Background This study examined whether the experiences of childhood or adolescent parental divorce/separation and parental alcohol problems affected the likelihood of offspring DSM-IV lifetime alcohol dependence, controlling for parental history of drug, depression, and antisocial behavior problems. Method Data were drawn from the 2001–2002 National Epidemiological Survey on Alcohol and Related Conditions (NESARC), a nationally representative United States survey of 43,093 civilian non-institutionalized participants aged 18 and older, interviewed in person. Logistic regression models were used to calculate the main and interaction effects of childhood or adolescent parental divorce/separation and parental history of alcohol problems on offspring lifetime alcohol dependence, after adjusting for parental history of drug, depression, and antisocial behavior problems. Results Childhood or adolescent parental divorce/separation and parental history of alcohol problems were significantly related to offspring lifetime alcohol dependence, after adjusting for parental history of drug, depression, and antisocial behavior problems. Experiencing parental divorce/separation during childhood, even in the absence of parental history of alcohol problems, remained a significant predictor of lifetime alcohol dependence. Experiencing both childhood or adolescent parental divorce/separation and parental alcohol problems had a significantly stronger impact on the risk for DSM-IV alcohol dependence than the risk incurred by either parental risk factor alone. Conclusions Further research is needed to better identify the factors that increase the risk for lifetime alcohol dependence among those who experience childhood or adolescent parental divorce/separation. PMID:18757141

  18. Childhood or adolescent parental divorce/separation, parental history of alcohol problems, and offspring lifetime alcohol dependence.

    PubMed

    Thompson, Ronald G; Lizardi, Dana; Keyes, Katherine M; Hasin, Deborah S

    2008-12-01

    This study examined whether the experiences of childhood or adolescent parental divorce/separation and parental alcohol problems affected the likelihood of offspring DSM-IV lifetime alcohol dependence, controlling for parental history of drug, depression, and antisocial behavior problems. Data were drawn from the 2001-2002 National Epidemiological Survey on Alcohol and Related Conditions (NESARC), a nationally representative United States survey of 43,093 civilian non-institutionalized participants aged 18 and older, interviewed in person. Logistic regression models were used to calculate the main and interaction effects of childhood or adolescent parental divorce/separation and parental history of alcohol problems on offspring lifetime alcohol dependence, after adjusting for parental history of drug, depression, and antisocial behavior problems. Childhood or adolescent parental divorce/separation and parental history of alcohol problems were significantly related to offspring lifetime alcohol dependence, after adjusting for parental history of drug, depression, and antisocial behavior problems. Experiencing parental divorce/separation during childhood, even in the absence of parental history of alcohol problems, remained a significant predictor of lifetime alcohol dependence. Experiencing both childhood or adolescent parental divorce/separation and parental alcohol problems had a significantly stronger impact on the risk for DSM-IV alcohol dependence than the risk incurred by either parental risk factor alone. Further research is needed to better identify the factors that increase the risk for lifetime alcohol dependence among those who experience childhood or adolescent parental divorce/separation.

  19. Nonadjacent Dependency Learning in Cantonese-Speaking Children With and Without a History of Specific Language Impairment.

    PubMed

    Iao, Lai-Sang; Ng, Lai Yan; Wong, Anita Mei Yin; Lee, Oi Ting

    2017-03-01

    This study investigated nonadjacent dependency learning in Cantonese-speaking children with and without a history of specific language impairment (SLI) in an artificial linguistic context. Sixteen Cantonese-speaking children with a history of SLI and 16 Cantonese-speaking children with typical language development (TLD) were tested with a nonadjacent dependency learning task using artificial languages that mimic Cantonese. Children with TLD performed above chance and were able to discriminate between trained and untrained nonadjacent dependencies. However, children with a history of SLI performed at chance and were not able to differentiate trained versus untrained nonadjacent dependencies. These findings, together with previous findings from English-speaking adults and adolescents with language impairments, suggest that individuals with atypical language development, regardless of age, diagnostic status, language, and culture, show difficulties in learning nonadjacent dependencies. This study provides evidence for early impairments to statistical learning in individuals with atypical language development.

  20. History of attention-deficit hyperactivity disorder symptoms and opioid dependence: a controlled study.

    PubMed

    Davids, Eugen; von Bünau, Ulla; Specka, Michael; Fischer, Barbara; Scherbaum, Norbert; Gastpar, Markus

    2005-02-01

    The co-occurrence of attention-deficit hyperactivity disorder (ADHD) and substance use disorders has received considerable attention in recent clinical and scientific investigations. These two disorders are linked to one another in a variety of ways. The core symptoms of ADHD may be mimicked by the effects of psychoactive substance use, making it difficult to diagnose one disorder in the presence of the other. Individuals with ADHD may demonstrate earlier onset of the substance abuse and a pattern of more frequent or intense use. ADHD symptoms were explored as possible antecedents of opioid dependence. A total of 109 adult opioid-dependent, treatment-seeking male and female outpatients were investigated with an extended clinical semistructured interview to collect sociodemographic, drug-related, and clinical data. The results indicate that ADHD alone does not predispose the development of opioid dependence in our sample. Childhood ADHD symptoms may nevertheless be found more frequently related to school performance problems and difficulties in social adaptation, which was identified in more than half of our population. Patients with ADHD history seemed to experience a drug abuse career with more complications which need to be recognized with focused attention in order to start earlier treatment strategies.

  1. Sense of control under uncertainty depends on people's childhood environment: a life history theory approach.

    PubMed

    Mittal, Chiraag; Griskevicius, Vladas

    2014-10-01

    Past research found that environmental uncertainty leads people to behave differently depending on their childhood environment. For example, economic uncertainty leads people from poor childhoods to become more impulsive while leading people from wealthy childhoods to become less impulsive. Drawing on life history theory, we examine the psychological mechanism driving such diverging responses to uncertainty. Five experiments show that uncertainty alters people's sense of control over the environment. Exposure to uncertainty led people from poorer childhoods to have a significantly lower sense of control than those from wealthier childhoods. In addition, perceptions of control statistically mediated the effect of uncertainty on impulsive behavior. These studies contribute by demonstrating that sense of control is a psychological driver of behaviors associated with fast and slow life history strategies. We discuss the implications of this for theory and future research, including that environmental uncertainty might lead people who grew up poor to quit challenging tasks sooner than people who grew up wealthy. 2014 APA, all rights reserved

  2. The Dependence of Galaxy Clustering on Stellar-mass Assembly History for LRGs

    NASA Astrophysics Data System (ADS)

    Montero-Dorta, Antonio D.; Pérez, Enrique; Prada, Francisco; Rodríguez-Torres, Sergio; Favole, Ginevra; Klypin, Anatoly; Cid Fernandes, Roberto; González Delgado, Rosa M.; Domínguez, Alberto; Bolton, Adam S.; García-Benito, Rubén; Jullo, Eric; Niemiec, Anna

    2017-10-01

    We analyze the spectra of 300,000 luminous red galaxies (LRGs) with stellar masses {M}* ≳ {10}11 {M}ȯ from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). By studying their star formation histories, we find two main evolutionary paths converging into the same quiescent galaxy population at z∼ 0.55. Fast-growing LRGs assemble 80% of their stellar mass very early on (z∼ 5), whereas slow-growing LRGs reach the same evolutionary state at z∼ 1.5. Further investigation reveals that their clustering properties on scales of ∼1–30 Mpc are, at a high level of significance, also different. Fast-growing LRGs are found to be more strongly clustered and reside in overall denser large-scale structure environments than slow-growing systems, for a given stellar-mass threshold. Our results show a dependence of clustering on a property that is directly related to the evolution of galaxies, i.e., the stellar-mass assembly history, for a homogeneous population of similar mass and color. In a forthcoming work, we will address the halo connection in the context of galaxy assembly bias.

  3. Dynamic history-dependent variational-hemivariational inequalities with applications to contact mechanics

    NASA Astrophysics Data System (ADS)

    Migórski, Stanislaw; Ogorzaly, Justyna

    2017-02-01

    In the paper we deliver a new existence and uniqueness result for a class of abstract nonlinear variational-hemivariational inequalities which are governed by two operators depending on the history of the solution, and include two nondifferentiable functionals, a convex and a nonconvex one. Then, we consider an initial boundary value problem which describes a model of evolution of a viscoelastic body in contact with a foundation. The contact process is assumed to be dynamic, and the friction is described by subdifferential boundary conditions. Both the constitutive law and the contact condition involve memory operators. As an application of the abstract theory, we provide a result on the unique weak solvability of the contact problem.

  4. Age-dependent flea (Siphonaptera) parasitism in rodents: a host's life history matters.

    PubMed

    Krasnov, Boris R; Stanko, Michal; Morand, Serge

    2006-04-01

    We studied age-dependent patterns of flea infestation in 7 species of rodents from Slovakia (Apodemus agrarius, A. flavicollis, A. sylvaticus, A. uralensis, Clethrionomys glareolus, Microtus arvalis, and M. subterraneus). We estimated the age of the host from its body mass and expected the host age-dependent pattern of flea abundance, the level of aggregation, and prevalence to be in agreement with theoretical predictions. We expected that the mean abundance and the level of aggregation of fleas would be lowest in hosts of smallest and largest size classes and highest in hosts of medium size classes, whereas pattern of variation of prevalence with host age would be either convex or asymptotic. In general, mean abundance and species richness of fleas increased with an increase in host age, although the pressure of flea parasitism in terms of number of fleas per unit host body surface decreased with host age. We found 2 clear patterns of the change in flea aggregation and prevalence with host age. The first pattern demonstrated a peak of flea aggregation and a trough of flea prevalence in animals of middle age classes (Apodemus species and C. glareolus). The second pattern was an increase of both flea aggregation and flea prevalence with host age (both Microtus species). Consequently, we did not find unequivocal evidence for the main role of either parasite-induced host mortality or acquired resistance in host age-dependent pattern of flea parasitism. Our results suggest that this pattern can be generated by various processes and is strongly affected by natural history parameters of a host species such as dispersal pattern, spatial distribution, and structure of shelters.

  5. White matter microstructure and impulsivity in methamphetamine dependence with and without a history of psychosis.

    PubMed

    Uhlmann, Anne; Fouche, Jean-Paul; Lederer, Katharina; Meintjes, Ernesta M; Wilson, Don; Stein, Dan J

    2016-06-01

    Methamphetamine (MA) use may lead to white matter injury and to a range of behavioral problems and psychiatric disorders, including psychosis. The present study sought to assess white matter microstructural impairment as well as impulsive behavior in MA dependence and MA-associated psychosis (MAP). Thirty patients with a history of MAP, 39 participants with MA dependence and 40 healthy controls underwent diffusion tensor imaging (DTI). Participants also completed the UPPS-P impulsive behavior questionnaire. We applied tract-based spatial statistics (TBSS) to investigate group differences in mean diffusivity (MD), fractional anisotropy (FA), axial (λ‖ ) and radial diffusivity (λ⊥ ), and their association with impulsivity scores and psychotic symptoms. The MAP group displayed widespread higher MD, λ‖ and λ⊥ levels compared to both controls and the MA group, and lower FA in extensive white matter areas relative to controls. MD levels correlated positively with negative psychotic symptoms in MAP. No significant DTI group differences were found between the MA group and controls. Both clinical groups showed high levels of impulsivity, and this dysfunction was associated with DTI measures in frontal white matter tracts. MAP patients show distinct patterns of impaired white matter integrity of global nature relative to controls and the MA group. Future work to investigate the precise nature and timing of alterations in MAP is needed. The results are further suggestive of frontal white matter pathology playing a role in impulsivity in MA dependence and MAP. Hum Brain Mapp 37:2055-2067, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. An exact solution for the history-dependent material and delamination behavior of laminated plates subjected to cylindrical bending

    SciTech Connect

    Williams, Todd O

    2009-01-01

    The exact solution for the history-dependent behavior of laminated plates subjected to cylindrical bending is presented. The solution represents the extension of Pagano's solution to consider arbitrary types of constitutive behaviors for the individual lamina as well as arbitrary types of cohesive zones models for delamination behavior. Examples of the possible types of material behavior are plasticity, viscoelasticity, viscoplasticity, and damaging. Examples of possible CZMs that can be considered are linear, nonlinear hardening, as well as nonlinear with softening. The resulting solution is intended as a benchmark solution for considering the predictive capabilities of different plate theories. Initial results are presented for several types of history-dependent material behaviors. It is shown that the plate response in the presence of history-dependent behaviors can differ dramatically from the elastic response. These results have strong implications for what constitutes an appropriate plate theory for modeling such behaviors.

  7. Age-dependent genetic variance in a life-history trait in the mute swan

    PubMed Central

    Charmantier, Anne; Perrins, Christopher; McCleery, Robin H; Sheldon, Ben C

    2005-01-01

    Genetic variance in characters under natural selection in natural populations determines the way those populations respond to that selection. Whether populations show temporal and/or spatial constancy in patterns of genetic variance and covariance is regularly considered, as this will determine whether selection responses are constant over space and time. Much less often considered is whether characters show differing amounts of genetic variance over the life-history of individuals. Such age-specific variation, if present, has important potential consequences for the force of natural selection and for understanding the causes of variation in quantitative characters. Using data from a long-term study of the mute swan Cygnus olor, we report the partitioning of phenotypic variance in timing of breeding (subject to strong natural selection) into component parts over 12 different age classes. We show that the additive genetic variance and heritability of this trait are strongly age-dependent, with higher additive genetic variance present in young and, particularly, old birds, but little evidence of any genetic variance for birds of intermediate ages. These results demonstrate that age can have a very important influence on the components of variation of characters in natural populations, and consequently that separate age classes cannot be assumed to be equivalent, either with respect to their evolutionary potential or response. PMID:16555791

  8. Age-dependent genetic variance in a life-history trait in the mute swan.

    PubMed

    Charmantier, Anne; Perrins, Christopher; McCleery, Robin H; Sheldon, Ben C

    2006-01-22

    Genetic variance in characters under natural selection in natural populations determines the way those populations respond to that selection. Whether populations show temporal and/or spatial constancy in patterns of genetic variance and covariance is regularly considered, as this will determine whether selection responses are constant over space and time. Much less often considered is whether characters show differing amounts of genetic variance over the life-history of individuals. Such age-specific variation, if present, has important potential consequences for the force of natural selection and for understanding the causes of variation in quantitative characters. Using data from a long-term study of the mute swan Cygnus olor, we report the partitioning of phenotypic variance in timing of breeding (subject to strong natural selection) into component parts over 12 different age classes. We show that the additive genetic variance and heritability of this trait are strongly age-dependent, with higher additive genetic variance present in young and, particularly, old birds, but little evidence of any genetic variance for birds of intermediate ages. These results demonstrate that age can have a very important influence on the components of variation of characters in natural populations, and consequently that separate age classes cannot be assumed to be equivalent, either with respect to their evolutionary potential or response.

  9. Single DNA molecule jamming and history-dependent dynamics during motor-driven viral packaging.

    PubMed

    Keller, Nicholas; Grimes, Shelley; Jardine, Paul J; Smith, Douglas E

    2016-08-01

    In many viruses molecular motors forcibly pack single DNA molecules to near-crystalline density into ~50-100 nm prohead shells(1, 2). Unexpectedly, we found that packaging frequently stalls in conditions that induce net attractive DNA-DNA interactions(3). Here, we present findings suggesting that this stalling occurs because the DNA undergoes a nonequilibrium jamming transition analogous to that observed in many soft-matter systems, such as colloidal and granular systems(4-8). Experiments in which conditions are changed during packaging to switch DNA-DNA interactions between purely repulsive and net attractive reveal strongly history-dependent dynamics. An abrupt deceleration is usually observed before stalling, indicating that a transition in DNA conformation causes an abrupt increase in resistance. Our findings suggest that the concept of jamming can be extended to a single polymer molecule. However, compared with macroscopic samples of colloidal particles(5) we find that single DNA molecules jam over a much larger range of densities. We attribute this difference to the nanoscale system size, consistent with theoretical predictions for jamming of attractive athermal particles.(9, 10).

  10. Single DNA molecule jamming and history-dependent dynamics during motor-driven viral packaging

    NASA Astrophysics Data System (ADS)

    Keller, Nicholas; Grimes, Shelley; Jardine, Paul J.; Smith, Douglas E.

    2016-08-01

    In many viruses, molecular motors forcibly pack single DNA molecules to near-crystalline density into ~50-100 nm prohead shells. Unexpectedly, we found that packaging frequently stalls in conditions that induce net attractive DNA-DNA interactions. Here, we present findings suggesting that this stalling occurs because the DNA undergoes a nonequilibrium jamming transition analogous to that observed in many soft-matter systems, such as colloidal and granular systems. Experiments in which conditions are changed during packaging to switch DNA-DNA interactions between purely repulsive and net attractive reveal strongly history-dependent dynamics. An abrupt deceleration is usually observed before stalling, indicating that a transition in DNA conformation causes an abrupt increase in resistance. Our findings suggest that the concept of jamming can be extended to a single polymer molecule. However, compared with macroscopic samples of colloidal particles we find that single DNA molecules jam over a much larger range of densities. We attribute this difference to the nanoscale system size, consistent with theoretical predictions for jamming of attractive athermal particles.

  11. Single DNA molecule jamming and history-dependent dynamics during motor-driven viral packaging

    PubMed Central

    Keller, Nicholas; Grimes, Shelley; Jardine, Paul J.; Smith, Douglas E.

    2016-01-01

    In many viruses molecular motors forcibly pack single DNA molecules to near-crystalline density into ~50–100 nm prohead shells1, 2. Unexpectedly, we found that packaging frequently stalls in conditions that induce net attractive DNA-DNA interactions3. Here, we present findings suggesting that this stalling occurs because the DNA undergoes a nonequilibrium jamming transition analogous to that observed in many soft-matter systems, such as colloidal and granular systems4–8. Experiments in which conditions are changed during packaging to switch DNA-DNA interactions between purely repulsive and net attractive reveal strongly history-dependent dynamics. An abrupt deceleration is usually observed before stalling, indicating that a transition in DNA conformation causes an abrupt increase in resistance. Our findings suggest that the concept of jamming can be extended to a single polymer molecule. However, compared with macroscopic samples of colloidal particles5 we find that single DNA molecules jam over a much larger range of densities. We attribute this difference to the nanoscale system size, consistent with theoretical predictions for jamming of attractive athermal particles.9, 10 PMID:27540410

  12. Thermal-history dependent magnetoelastic transition in (Mn,Fe){sub 2}(P,Si)

    SciTech Connect

    Miao, X. F. Dijk, N. H. van; Brück, E.; Caron, L.; Gercsi, Z.; Daoud-Aladine, A.

    2015-07-27

    The thermal-history dependence of the magnetoelastic transition in (Mn,Fe){sub 2}(P,Si) compounds has been investigated using high-resolution neutron diffraction. As-prepared samples display a large difference in paramagnetic-ferromagnetic (PM-FM) transition temperature compared to cycled samples. The initial metastable state transforms into a lower-energy stable state when the as-prepared sample crosses the PM-FM transition for the first time. This additional transformation is irreversible around the transition temperature and increases the energy barrier which needs to be overcome through the PM-FM transition. Consequently, the transition temperature on first cooling is found to be lower than on subsequent cycles characterizing the so-called “virgin effect.” High-temperature annealing can restore the cycled sample to the high-temperature metastable state, which leads to the recovery of the virgin effect. A model is proposed to interpret the formation and recovery of the virgin effect.

  13. Measuring Temperaturelike State Variables in History-Dependent Jammed Granular Systems

    NASA Astrophysics Data System (ADS)

    Bililign, Ephraim; Daniels, Karen

    Granular systems are athermal, thus a complete statistical mechanics framework must be based on a set of macroscopic state variables which excludes temperature. One leading theory incorporates a stress-based ensemble, and predicts a Boltzmann-like distribution of the force-moment tensor with respect to the conjugate, temperature-like variable, angoricity. We experimentally test this theory on a static, bidisperse, two-dimensional packing of discs. Basal friction is eliminated by floating the discs on a sub-fluidizing upflow of air, and the packings are subjected to either uniaxial compression or simple shear. We simultaneously measure the contact forces acting on each disc using photoelasticity. These measurements are repeated over many configurations of discs by dilating and rearranging the system, and the angoricity is computed as a function of the confining pressure. In particular, we test the predicted linear relationship between angoricity and pressure. Comparison to prior results and numerical simulations also suggests a history-dependent angoricity, an undesirable feature in the proposed state variable.

  14. Associations Between Family History of Substance Use, Childhood Trauma, and Age of First Drug Use in Persons With Methamphetamine Dependence.

    PubMed

    Svingen, Leah; Dykstra, Rita E; Simpson, Jamie L; Jaffe, Anna E; Bevins, Rick A; Carlo, Gustavo; DiLillo, David; Grant, Kathleen M

    2016-01-01

    The current study examined the association among family history of substance use problems, childhood maltreatment, and age of first drug use in a sample of men and women seeking treatment for methamphetamine dependence. Various forms of childhood maltreatment were considered as mediators of the association between family history of substance use problems and age of first drug use. Participants (N = 99, 40% women, mean age 33) who were under treatment for methamphetamine dependence completed a baseline interview that obtained demographic information, past substance use by participants, history of drug/alcohol problems in their family of origin, and age at first use of any drug (excluding alcohol and tobacco). The Early Trauma Inventory Self-Report-Short Form was used to assess child maltreatment experiences before the age of 18. Family history of substance use problems and childhood physical (but not emotional or sexual) trauma significantly predicted age of first drug use. Further, childhood physical trauma mediated the association between family history of substance use problems and age of first drug use. These findings suggest that the experience of childhood physical abuse may be an important mechanism through which family history of substance use is associated with an earlier age of first drug use.

  15. Context-Dependent Effects of Ranaviral Infection on Northern Leopard Frog Life History Traits

    PubMed Central

    Echaubard, Pierre; Little, Kevin; Pauli, Bruce; Lesbarrères, David

    2010-01-01

    Pathogens have important effects on host life-history traits, but the magnitude of these effects is often strongly context-dependent. The outcome of an interaction between a host and an infectious agent is often associated with the level of stress experienced by the host. Ranavirus causes disease and mortality in amphibian populations in various locations around the world, but most known cases of ranaviral infection have occurred in North America and the United Kingdom. While Ranavirus virulence has been investigated, the outcome of Ranavirus infection has seldom been related to the host environment. In a factorial experiment, we exposed Northern leopard frog (Lithobates pipiens, formerly Rana pipiens) tadpoles to different concentrations of Ranavirus and investigated the effect of host density on certain life-history traits, namely survival, growth rate, developmental stage and number of days from virus exposure to death. Our results suggest a prominent role of density in driving the direction of the interaction between L. pipiens tadpoles and Ranavirus. We showed that increasing animal holding density is detrimental for host fitness as mortality rate is higher, day of death earlier, development longer and growth rate significantly lower in high-density tanks. We observed a linear increase of detrimental effects when Ranavirus doses increased in low-density conditions, with control tadpoles having a significantly higher overall relative fitness. However, this pattern was no longer observed in high-density conditions, where the effects of increasing Ranavirus dose were limited. Infected and control animals fitness were consequently similar. We speculate that the host may eventually diverts the energy required for a metabolic/immune response triggered by the infection (i.e., direct costs of the infection) to better cope with the increase in environmental “stress” associated with high density (i.e., indirect benefits of the infection). Our results illustrate how

  16. Decreased Sensitivity to Long-Distance Dependencies in Children with a History of Specific Language Impairment: Electrophysiological Evidence

    ERIC Educational Resources Information Center

    Purdy, J. D.; Leonard, Laurence B.; Weber-Fox, Christine; Kaganovich, Natalya

    2014-01-01

    Purpose: One possible source of tense and agreement limitations in children with specific language impairment (SLI) is a weakness in appreciating structural dependencies that occur in many sentences in the input. This possibility was tested in the present study. Method: Children with a history of SLI (H-SLI; n = 12; M = 9;7 [years;months]) and…

  17. THE MASS-DEPENDENT STAR FORMATION HISTORIES OF DISK GALAXIES: INFALL MODEL VERSUS OBSERVATIONS

    SciTech Connect

    Chang, R. X.; Hou, J. L.; Shen, S. Y.; Shu, C. G.

    2010-10-10

    We introduce a simple model to explore the star formation histories of disk galaxies. We assume that the disk originate and grows by continuous gas infall. The gas infall rate is parameterized by the Gaussian formula with one free parameter: the infall-peak time t{sub p} . The Kennicutt star formation law is adopted to describe how much cold gas turns into stars. The gas outflow process is also considered in our model. We find that, at a given galactic stellar mass M{sub *}, the model adopting a late infall-peak time t{sub p} results in blue colors, low-metallicity, high specific star formation rate (SFR), and high gas fraction, while the gas outflow rate mainly influences the gas-phase metallicity and star formation efficiency mainly influences the gas fraction. Motivated by the local observed scaling relations, we 'construct' a mass-dependent model by assuming that the low-mass galaxy has a later infall-peak time t{sub p} and a larger gas outflow rate than massive systems. It is shown that this model can be in agreement with not only the local observations, but also with the observed correlations between specific SFR and galactic stellar mass SFR/M{sub *} {approx} M{sub *} at intermediate redshifts z < 1. Comparison between the Gaussian-infall model and the exponential-infall model is also presented. It shows that the exponential-infall model predicts a higher SFR at early stage and a lower SFR later than that of Gaussian infall. Our results suggest that the Gaussian infall rate may be more reasonable in describing the gas cooling process than the exponential infall rate, especially for low-mass systems.

  18. Mechanical History Dependence in Carbon Black Suspensions for Flow Batteries: A Rheo-Impedance Study

    PubMed Central

    2017-01-01

    We studied the effects of shear and its history on suspensions of carbon black (CB) in lithium ion battery electrolyte via simultaneous rheometry and electrical impedance spectroscopy. Ketjen black (KB) suspensions showed shear thinning and rheopexy and exhibited a yield stress. Shear step experiments revealed a two time scale response. The immediate effect of decreasing the shear rate is an increase in both viscosity and electronic conductivity. In a much slower secondary response, both quantities change in the opposite direction, leading to a reversal of the initial change in the conductivity. Stepwise increases in the shear rate lead to similar responses in the opposite direction. This remarkable behavior is consistent with a picture in which agglomerating KB particles can stick directly on contact, forming open structures, and then slowly interpenetrate and densify. The fact that spherical CB particles show the opposite slow response suggests that the fractal structure of the KB primary units plays an important role. A theoretical scheme was used to analyze the shear and time-dependent viscosity and conductivity. Describing the agglomerates as effective hard spheres with a fractal architecture and using an effective medium approximation for the conductivity, we found the changes in the derived suspension structure to be in agreement with our qualitative mechanistic picture. This behavior of KB in flow has consequences for the properties of the gel network that is formed immediately after the cessation of shear: both the yield stress and the electronic conductivity increase with the previously applied shear rate. Our findings thus have clear implications for the operation and filling strategies of semisolid flow batteries. PMID:28122184

  19. Opposite Cannabis-Cognition Associations in Psychotic Patients Depending on Family History

    PubMed Central

    González-Pinto, Ana; González-Ortega, Itxaso; Alberich, Susana; Ruiz de Azúa, Sonia; Bernardo, Miguel; Bioque, Miquel; Cabrera, Bibiana; Corripio, Iluminada; Arango, Celso; Lobo, Antonio; Sánchez-Torres, Ana M.; Cuesta, Manuel J.

    2016-01-01

    The objective of this study is to investigate cognitive performance in a first-episode psychosis sample, when stratifying the interaction by cannabis use and familial or non-familial psychosis. Hierarchical-regression models were used to analyse this association in a sample of 268 first-episode psychosis patients and 237 controls. We found that cannabis use was associated with worse working memory, regardless of family history. However, cannabis use was clearly associated with worse cognitive performance in patients with no family history of psychosis, in cognitive domains including verbal memory, executive function and global cognitive index, whereas cannabis users with a family history of psychosis performed better in these domains. The main finding of the study is that there is an interaction between cannabis use and a family history of psychosis in the areas of verbal memory, executive function and global cognition: that is, cannabis use is associated with a better performance in patients with a family history of psychosis and a worse performance in those with no family history of psychosis. In order to confirm this hypothesis, future research should explore the actual expression of the endocannabinoid system in patients with and without a family history of psychosis. PMID:27513670

  20. Opposite Cannabis-Cognition Associations in Psychotic Patients Depending on Family History.

    PubMed

    González-Pinto, Ana; González-Ortega, Itxaso; Alberich, Susana; Ruiz de Azúa, Sonia; Bernardo, Miguel; Bioque, Miquel; Cabrera, Bibiana; Corripio, Iluminada; Arango, Celso; Lobo, Antonio; Sánchez-Torres, Ana M; Cuesta, Manuel J

    2016-01-01

    The objective of this study is to investigate cognitive performance in a first-episode psychosis sample, when stratifying the interaction by cannabis use and familial or non-familial psychosis. Hierarchical-regression models were used to analyse this association in a sample of 268 first-episode psychosis patients and 237 controls. We found that cannabis use was associated with worse working memory, regardless of family history. However, cannabis use was clearly associated with worse cognitive performance in patients with no family history of psychosis, in cognitive domains including verbal memory, executive function and global cognitive index, whereas cannabis users with a family history of psychosis performed better in these domains. The main finding of the study is that there is an interaction between cannabis use and a family history of psychosis in the areas of verbal memory, executive function and global cognition: that is, cannabis use is associated with a better performance in patients with a family history of psychosis and a worse performance in those with no family history of psychosis. In order to confirm this hypothesis, future research should explore the actual expression of the endocannabinoid system in patients with and without a family history of psychosis.

  1. Assessing the risks and benefits of benzodiazepines for anxiety disorders in patients with a history of substance abuse or dependence.

    PubMed

    Posternak, M A; Mueller, T I

    2001-01-01

    In this article, the authors reevaluate the traditional position that benzodiazepines should be avoided in anxiety disorder patients with a history of substance abuse or dependence. The efficacy of benzodiazepines in each of the anxiety disorders is reviewed, as are their side effects and toxicity. The definitions of benzodiazepine abuse and dependence are discussed, and relevant animal, experimental, and clinical data are reviewed and analyzed. A manual and computerized (MEDLINE) search was performed from 1966 to the present to examine the English-language literature published on benzodiazepines, substance abuse, and each of the anxiety disorders listed in DSM-IV. The authors found that benzodiazepines have demonstrated efficacy in generalized anxiety disorder, panic disorder, and agoraphobia; they are promising agents in the treatment of social phobia and alcohol-induced anxiety disorders. They are generally well tolerated. There is much ambiguity over appropriate definitions for benzodiazepine abuse and dependence: although most benzodiazepine abusers concurrently abuse other substances, there is little evidence to indicate that a history of substance abuse is a major risk factor for future benzodiazepine abuse or dependence. Furthermore, benzodiazepines do not appear to induce relapse of substance abuse in these patients. The authors conclude that the position that benzodiazepines are contraindicated in former substance abusers appears to lack empirical justification. Benzodiazepines may be indicated in certain patients with anxiety disorders and a history of substance abuse or dependence.

  2. An investigation of the effects of history dependent damage in time dependent fracture mechanics, Phase 1, constant load conditions

    SciTech Connect

    Brust, F.W.; Krishnaswamy, P.; Ghadiali, N.D.

    1991-11-14

    In the following section a brief review of constitutive models is presented along with the implications of using them in creep crack growth studies under variable loads. The model searched for this study, is discussed along with is special features that make is particularly suitable for this investigation. This model is based on the creep hardening surface and is particularly useful for variable and fully reversed load histories. In Section 3 an implicit finite element algorithm for this model is derived. Details regarding implementation of this method into FVP and existing FE program to study creep crack growth, are also discussed. The results of the algorithm are verified against closed form solutions for simple geometries in Section 4. Sources of error and differences between using explicit and implicit schemes are also presented. Section 5 compares the numerical results with experimental data for the case of combined tension and torsion and fully reversed load histories. Section 6 provides results of some of the constant load creep crack growth analyses that have been performed to date. Because a wealth of experimental data has been developed for creep crack under constant load conditions, the need to develop our own creep growth data for this study was minimal. Conclusions of the Phase 1 work as well as work planned for the future are discussed in Section 7. Finally, Sections 8 and 9 discuss publications and the Phase 2 effort, respectively. Finally, the implementation of large strain and friction/contact algorithms into the finite element code and the implementation of three additional non-linear constitutive laws and the Walker Model are not discussed here. The large strain algorithm is complete, the endochronic theory is nearly complete, while subroutines for the Bodner and Walker models were obtained from the agencies described above.

  3. A Family History of Substance Dependence Obscures the Group Differences in Brain Function Associated with HIV-1 and ART

    PubMed Central

    Bauer, L.O.

    2012-01-01

    BACKGROUND Recently, the NIH called for additional research on the topic of viral and host factors contributing to impaired cognitive and neural function in HIV/AIDS patients and their response to antiretroviral treatment. This investigation responds to that call by examining a host factor, a family history of substance dependence, often overlooked in cognitive and neuroimaging studies of HIV/AIDS. METHODS We categorized 146 HIV-1 seropositive patients receiving antiretroviral treatment (ART) and 92 seronegative volunteers by the presence or absence of alcohol, cocaine, or heroin dependence affecting a biological parent. Seropositive patients were further categorized by the estimated ability of their individual ART regimens to penetrate the CNS. The indicator of brain function was a 3–7 Hz oscillatory electroencephalographic response (theta ERO) evoked by target stimuli presented during a simple selective attention task. RESULTS The analysis revealed that the presence of a family history of substance dependence obscured the reduction in frontal theta ERO power accompanying the presence of HIV-1 as well as the improvement in frontal theta ERO power accompanying treatment with ART agents estimated to have greater (n=41) versus lesser (n=105) CNS penetrance. Secondary analyses employing sLORETA source localization techniques revealed that the source of the theta ERO response was similarly reduced by the presence of either HIV-1 or a family history of substance dependence. CONCLUSIONS We conclude that a family history of substance dependence complicates and obscures the subtle neurophysiological changes which typically accompany HIV/AIDS and ART. Studies of new therapeutic agents for HIV-1-associated cognitive and neurophysiological impairments must consider this complication and exclude or control it. PMID:22749564

  4. A family history of substance dependence obscures the group differences in brain function associated with HIV-1 and ART.

    PubMed

    Bauer, L O

    2013-01-01

    Recently, the NIH called for additional research on the topic of viral and host factors contributing to impaired cognitive and neural function in HIV/AIDS patients and their response to antiretroviral treatment. This investigation responds to that call by examining a host factor, a family history of substance dependence, often overlooked in cognitive and neuroimaging studies of HIV/AIDS. We categorized 146 HIV-1 seropositive patients receiving antiretroviral treatment (ART) and 92 seronegative volunteers by the presence or absence of alcohol, cocaine, or heroin dependence affecting a biological parent. Seropositive patients were further categorized by the estimated ability of their individual ART regimens to penetrate the CNS. The indicator of brain function was a 3-7Hz oscillatory electroencephalographic response (theta ERO) evoked by target stimuli presented during a simple selective attention task. The analysis revealed that the presence of a family history of substance dependence obscured the reduction in frontal theta ERO power accompanying the presence of HIV-1 as well as the improvement in frontal theta ERO power accompanying treatment with ART agents estimated to have greater (n=41) versus lesser (n=105) CNS penetrance. Secondary analyses employing sLORETA source localization techniques revealed that the source of the theta ERO response was similarly reduced by the presence of either HIV-1 or a family history of substance dependence. We conclude that a family history of substance dependence complicates and obscures the subtle neurophysiological changes which typically accompany HIV/AIDS and ART. Studies of new therapeutic agents for HIV-1-associated cognitive and neurophysiological impairments must consider this complication and exclude or control it. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Roles of density-dependent growth and life history evolution in accounting for fisheries-induced trait changes.

    PubMed

    Eikeset, Anne Maria; Dunlop, Erin S; Heino, Mikko; Storvik, Geir; Stenseth, Nils C; Dieckmann, Ulf

    2016-12-27

    The relative roles of density dependence and life history evolution in contributing to rapid fisheries-induced trait changes remain debated. In the 1930s, northeast Arctic cod (Gadus morhua), currently the world's largest cod stock, experienced a shift from a traditional spawning-ground fishery to an industrial trawl fishery with elevated exploitation in the stock's feeding grounds. Since then, age and length at maturation have declined dramatically, a trend paralleled in other exploited stocks worldwide. These trends can be explained by demographic truncation of the population's age structure, phenotypic plasticity in maturation arising through density-dependent growth, fisheries-induced evolution favoring faster-growing or earlier-maturing fish, or a combination of these processes. Here, we use a multitrait eco-evolutionary model to assess the capacity of these processes to reproduce 74 y of historical data on age and length at maturation in northeast Arctic cod, while mimicking the stock's historical harvesting regime. Our results show that model predictions critically depend on the assumed density dependence of growth: when this is weak, life history evolution might be necessary to prevent stock collapse, whereas when a stronger density dependence estimated from recent data is used, the role of evolution in explaining fisheries-induced trait changes is diminished. Our integrative analysis of density-dependent growth, multitrait evolution, and stock-specific time series data underscores the importance of jointly considering evolutionary and ecological processes, enabling a more comprehensive perspective on empirically observed stock dynamics than previous studies could provide.

  6. The history dependence of force production in mammalian skeletal muscle following stretch-shortening and shortening-stretch cycles.

    PubMed

    Herzog, W; Leonard, T R

    2000-05-01

    The purpose of this study was to determine the history dependence of force production during and following stretch-shortening and shortening-stretch cycles in mammalian skeletal muscle. Thirty-three different isometric, stretch, shortening, stretch-shortening and shortening-stretch experiments were preformed in cat soleus (n=8) using previously established methods. Stretch-shortening and shortening-stretch cycles are not commutative with respect to the isometric forces following the length changes. Whereas force depression following shortening is virtually unaffected by previous stretching of the muscle, force enhancement following stretch depends in a dose-dependent manner on the amount of muscle shortening preceding the stretch. The history dependence of isometric force following shortening-stretch cycles can conveniently be modelled using an elastic (compressive and tensile) element that engages at the length of muscle activation. Such an "elastic" mechanism has been proposed by Edman and Tsuchiya (1996) (Edman, K.A. P., Tsuchiya, T., 1996. Strain of passive elements during force enhancement by stretch in frog mucle fibres. Journal of Physiology 490. 1, 191-205) based on experimental observations, and has been implemented theoretically in a rheological model of muscle (Forcinito et al., 1997) (Forcinito, M., Epstein, M., Herzog, W., 1997. Theoretical considerations on myofibril stiffness. Biophysics Journal 72, 1278-1286). The history dependence of isometric force following stretch-shortening cycles appears independent of the stretch preceding the shortening, except perhaps, if stretching occurs at very high speeds (i.e. 6-10 times fibre length per second). The results of this study are hard to reconcile with the two major mechanisms associated with history dependence of force production: sarcomere length non-uniformity (Edman et al., 1993) and stress-induced cross-bridge inhibition (Maréchal and Plaghki, 1979) (Maréchal, G., Plaghki, L., 1979. The deficit of

  7. Direct Effects of Light on Alertness, Vigilance, and the Waking Electroencephalogram in Humans Depend on Prior Light History

    PubMed Central

    Chang, Anne-Marie; Scheer, Frank A. J. L.; Czeisler, Charles A.; Aeschbach, Daniel

    2013-01-01

    Study Objectives: Light can induce an acute alerting response in humans; however, it is unknown whether the magnitude of this response is simply a function of the absolute illuminance of the light itself, or whether it depends on illuminance history preceding the stimulus. Here, we compared the effects of illuminance history on the alerting response to a subsequent light stimulus. Design: A randomized, crossover design was used to compare the effect of two illuminance histories (1 lux vs. 90 lux) on the alerting response to a 6.5-h 90-lux light stimulus during the biological night. Setting: Intensive Physiologic Monitoring Unit, Brigham and Women's Hospital, Boston, MA. Participants: Fourteen healthy young adults (6 F; 23.5 ± 2.9 years). Interventions: Participants were administered two 6.5-h light exposures (LE) of 90 lux during the biological night. For 3 days prior to each LE, participants were exposed to either 1 lux or 90 lux during the wake episode. Measurements and Results: The alerting response to light was assessed using subjective sleepiness ratings, lapses of attention, and reaction times as measured with an auditory psychomotor vigilance task, as well as power density in the delta/theta range of the waking EEG. The alerting response to light was greater and lasted longer when the LE followed exposure to 1 lux compared to 90 lux light. Conclusion: The magnitude and duration of the alerting effect of light at night depends on the illuminance history and appears to be subject to sensitization and adaptation. Citation: Chang AM; Scheer FAJL; Czeisler CA; Aeschbach D. Direct effects of light on alertness, vigilance, and the waking electroencephalogram in humans depend on prior light history. SLEEP 2013;36(8):1239-1246. PMID:23904684

  8. Carbon sequestration potential of grazed pasture depends on prior management history

    USDA-ARS?s Scientific Manuscript database

    Grazed pastures are often assumed to be net sinks for removing carbon dioxide from the atmosphere and thus, are promoted as a management practice that can help mitigate climate change. The ability to serve as a C sink is especially pronounced following a history of tillage and row crop production. I...

  9. Saturation-history-dependent wettability and its impact on macroscale two-phase flow: As determined by lattice Boltzmann modeling

    NASA Astrophysics Data System (ADS)

    Landry, C. J.; Karpyn, Z. T.

    2012-12-01

    Macroscale multiphase flow properties (i.e. relative permeability and capillary pressure) are strongly dependent on wettability. The wettability of a porous medium is initially determined by its mineral composition. However, brines and oils can alter the wettability of porous media, such that the multiphase flow properties of a rock can be significantly dependent on saturation history. Subsequently, the majority of consolidated and unconsolidated porous media have a mixed or fractional wettability. Here we investigate the dependence of macroscale flow properties on wettability and saturation history using lattice Boltzmann (LB) modeling. In a previous experiment we imaged oil and water distribution in two bead packs, one strongly water-wet, and the other weakly oil-wet, at the pore-scale using x-ray computed microtomography (CMT). To validate our approach the specific fluid surface areas determined by LB simulations are compared to those imaged using CMT. To simulate the alteration of wettability by fluid residence the contact angle of solid surfaces is increased or decreased with respect to fluid phase in contact with the solid surface. The relative permeability and capillary pressure curves are then determined for both the unaltered and altered porous media using LB. We then are able to interrogate the interplay between the initial wettability and altered wettability resulting from saturation history on macroscale flow properties.

  10. Trait assembly in grasslands depends on habitat history and spatial scale.

    PubMed

    Saar, Liina; de Bello, Francesco; Pärtel, Meelis; Helm, Aveliina

    2017-05-01

    During the past century, grasslands in Europe have undergone marked changes in land-use, leading to a decline in plant diversity both at local and regional scales, thus possibly also affecting the mechanisms of species sorting into local communities. We studied plant species assembly in grasslands with differing habitat history and hypothesised that trait divergence prevails in historical grasslands due to niche differentiation and trait convergence prevails in more dynamic grasslands due to competitive exclusion and dispersal limitation. We tested these hypotheses in 35 grassland complexes in Estonia, containing neighbouring grassland habitats with different land-use histories: continuously managed open historical grassland, currently overgrown former grassland and young developing grassland. We assessed species assembly patterns in each grassland type for finer scale-a 2 × 2 m plot scale from a local community pool and for broader scale-a local community from the habitat species pool for that grassland stage and observed changes in trait means at finer scale. We found that grasslands with long management history are assembled differently from former grasslands or young developing grasslands. In historical grasslands, divergence or random patterns prevailed at finer scale species assembly while in former or developing grasslands, mostly convergence patterns prevailed. With increasing scale convergence patterns become more prevalent in all grassland types. We conclude that land-use history is an important factor to consider when assessing grassland functional trait assembly, particularly at small scales. Understanding the mechanisms behind species assembly and their relationship with land-use history is vital for habitat conservation and restoration.

  11. Theory of the dependence of population levels on environmental history for semelparous species with short reproductive seasons.

    PubMed

    Coleman, B D; Hsieh, Y H

    1979-10-01

    A population that is strongly self-regulating through density-dependent effects is expected to be such that, if many generations have elapsed since its establishment, its present size should not be sensitive to its initial size but should instead be determined by the history of the variables that describe the influence of the environment on fecundity, mortality, and dispersal. Here we discuss the dependence of abundance on environmental history for a semelparous population in which reproduction is synchronous. It is assumed that at each instant t: (i) the rate of loss of members of age a by mortality and dispersal is given by a function rho of t, a, and the present number x = x(a,t) of such members; and (ii) the number x(0,t) of members born in the population is given by a function F of t and the number of x(a(f),t) at a specified age a(f) of fecundity. It is further assumed that the functions rho and F have the forms rho(x,a,t) = pi(1)(a,t)x + pi(2)(a,t)x(2) and F(x(a(f),t),t) = nu(t)x(a(f),t). For such a population, a change in the environment is significant only if it results in a change in nu(t) pi(1)(a,t), or pi(2)(a,t), and, hence, the history of the environment up to time t is described by giving nu(tau), pi(1)(a,tau), and pi(2)(a,tau) for each tau dependence of x on the history of the environment can be calculated explicitly and has certain properties of "fading memory"; i.e., environmental events that occurred in the remote past have less effect upon the present abundance than comparable events in the recent past.

  12. Treatment of patients with myocardial infarction depends on history of cancer.

    PubMed

    Rohrmann, Sabine; Witassek, Fabienne; Erne, Paul; Rickli, Hans; Radovanovic, Dragana

    2017-09-01

    Although cancer treatment considerably affects cardiovascular health, little is known about how cancer patients are treated for an acute myocardial infarction. We aimed to investigate whether acute myocardial infarction patients with a history of cancer received the same guideline recommended treatment as those acute myocardial infarction patients without and whether they differ with respect to inhospital outcome. All patients with ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction, enrolled between 2002 and mid-2015 in the acute myocardial infarction in Switzerland (AMIS Plus) registry with comorbidity data based on the Charlson comorbidity index were analysed. Patients were classified as having cancer if one of the cancer diseases of the Charlson comorbidity index was indicated. Immediate treatment strategies and inhospital outcomes were compared between groups using propensity score matching. Of 35,249 patients, 1981 (5.6%) had a history of cancer. After propensity score matching for age, gender, Killip class >2, ST-segment elevation myocardial infarction and renal disease (1981 patients per group), significant differences were no longer found for a history of acute myocardial infarction, hypertension, diabetes, heart failure and cerebrovascular disease between cancer and non-cancer patients. However, cancer patients underwent percutaneous coronary intervention less frequently (odds ratio (OR) 0.76; 95% confidence interval (CI) 0.67-0.88) and received P2Y12 blockers (OR 0.82; 95% CI 0.71-0.94) and statins (OR 0.87; 95% CI 0.76-0.99) less frequently. Inhospital mortality was significantly higher in cancer patients (10.7% vs. 7.6%, OR 1.45; 95% CI 1.17-1.81). However, the main cause of death was cardiac in both groups ( P=0.06). Acute myocardial infarction patients with a history of cancer were less likely to receive guideline recommended treatment and had worse inhospital outcomes than non-cancer patients.

  13. Response of single bacterial cells to stress gives rise to complex history dependence at the population level

    PubMed Central

    Mathis, Roland; Ackermann, Martin

    2016-01-01

    Most bacteria live in ever-changing environments where periods of stress are common. One fundamental question is whether individual bacterial cells have an increased tolerance to stress if they recently have been exposed to lower levels of the same stressor. To address this question, we worked with the bacterium Caulobacter crescentus and asked whether exposure to a moderate concentration of sodium chloride would affect survival during later exposure to a higher concentration. We found that the effects measured at the population level depended in a surprising and complex way on the time interval between the two exposure events: The effect of the first exposure on survival of the second exposure was positive for some time intervals but negative for others. We hypothesized that the complex pattern of history dependence at the population level was a consequence of the responses of individual cells to sodium chloride that we observed: (i) exposure to moderate concentrations of sodium chloride caused delays in cell division and led to cell-cycle synchronization, and (ii) whether a bacterium would survive subsequent exposure to higher concentrations was dependent on the cell-cycle state. Using computational modeling, we demonstrated that indeed the combination of these two effects could explain the complex patterns of history dependence observed at the population level. Our insight into how the behavior of single cells scales up to processes at the population level provides a perspective on how organisms operate in dynamic environments with fluctuating stress exposure. PMID:26960998

  14. Response of single bacterial cells to stress gives rise to complex history dependence at the population level.

    PubMed

    Mathis, Roland; Ackermann, Martin

    2016-04-12

    Most bacteria live in ever-changing environments where periods of stress are common. One fundamental question is whether individual bacterial cells have an increased tolerance to stress if they recently have been exposed to lower levels of the same stressor. To address this question, we worked with the bacterium Caulobacter crescentus and asked whether exposure to a moderate concentration of sodium chloride would affect survival during later exposure to a higher concentration. We found that the effects measured at the population level depended in a surprising and complex way on the time interval between the two exposure events: The effect of the first exposure on survival of the second exposure was positive for some time intervals but negative for others. We hypothesized that the complex pattern of history dependence at the population level was a consequence of the responses of individual cells to sodium chloride that we observed: (i) exposure to moderate concentrations of sodium chloride caused delays in cell division and led to cell-cycle synchronization, and (ii) whether a bacterium would survive subsequent exposure to higher concentrations was dependent on the cell-cycle state. Using computational modeling, we demonstrated that indeed the combination of these two effects could explain the complex patterns of history dependence observed at the population level. Our insight into how the behavior of single cells scales up to processes at the population level provides a perspective on how organisms operate in dynamic environments with fluctuating stress exposure.

  15. A History of Alcohol Dependence Augments HIV-associated Neurocognitive Deficits in Persons Aged 60 and Older

    PubMed Central

    Gongvatana, Assawin; Morgan, Erin E.; Iudicello, Jennifer E.; Letendre, Scott L.; Grant, Igor; Woods, Steven Paul

    2014-01-01

    Background Excessive alcohol use is common among people living with HIV. Given the growing prevalence of older HIV+ adults, and observations indicating higher risk for neurocognitive impairment in older adults with either HIV infection or alcoholism, an increased understanding of their combined impact in the context of this increasingly aged population is crucial. Methods We conducted comprehensive neurocognitive assessment in 112 older HIV+ individuals aged 50 to 69 years. Regression analyses were conducted to examine the interaction between age and the presence of lifetime alcohol dependence on neurocognitive measures, controlling for years of education, hepatitis C serostatus, and lifetime non-alcohol substance use disorder. Results Significant interactions of age and alcohol dependence history were found for global neurocognitive function, which was driven by the domains of executive function, processing speed, and semantic memory. Follow-up analyses indicated adverse effects of alcohol use history on neurocognitive measures that were evident only in HIV+ individuals 60 years and older. Conclusions While mounting evidence in younger cohorts indicates adverse synergistic HIV/alcohol effects on neurocognitive function, our novel preliminary findings in this elderly HIV+ cohort demonstrated the importance of even a relatively distant alcohol use history on the expression of HIV-associated neurocognitive disorders that may not become apparent until much later in life. PMID:25201556

  16. The viscoelastic properties of processed cheeses depend on their thermal history and fat polymorphism.

    PubMed

    Gliguem, Hela; Lopez, Christelle; Michon, Camille; Lesieur, Pierre; Ollivon, Michel

    2011-04-13

    Both the composition and the thermal kinetics that are applied to processed cheeses can affect their texture. This study investigated the effect of the storage conditions and thermal history on the viscoelastic properties of processed cheese and the physical properties of the fat phase. The microstructure of processed cheese has been characterized. Using a combination of physical techniques such as rheometry, differential scanning calorimetry, and X-ray diffraction, the partial crystallization of fat and the polymorphism of triacylglycerols (TG; main constituents of milk fat) were related to changes in the elastic modulus and tan δ as a function of temperature. In the small emulsion droplets (<1 μm) dispersed in processed cheeses, the solid fat phase was studied at a molecular level and showed differences as a function of the thermal history. Storage of processed cheese at 4 °C and its equilibration at 25 °C lead to partial crystallization of the fat phase, with the formation of a β' 2 L (40.9 Å) structure; on cooling at 2 °C min(-1), the formation of an α 3 L (65.8 Å) structure was characterized. The cooling of processed cheese from 60 to -10 °C leads to the formation of a single type of crystal: α 3 L (72 Å). Structural reorganizations of the solid fat phase characterized on heating allowed the interpretation of the elastic modulus evolution of processed cheese. This study evidenced polymorphism of TG in a complex food product such as processed cheese and allowed a better understanding of the viscoelastic properties as a function of the thermal history.

  17. Roles of density-dependent growth and life history evolution in accounting for fisheries-induced trait changes

    PubMed Central

    Eikeset, Anne Maria; Dunlop, Erin S.; Heino, Mikko; Storvik, Geir; Stenseth, Nils C.; Dieckmann, Ulf

    2016-01-01

    The relative roles of density dependence and life history evolution in contributing to rapid fisheries-induced trait changes remain debated. In the 1930s, northeast Arctic cod (Gadus morhua), currently the world’s largest cod stock, experienced a shift from a traditional spawning-ground fishery to an industrial trawl fishery with elevated exploitation in the stock’s feeding grounds. Since then, age and length at maturation have declined dramatically, a trend paralleled in other exploited stocks worldwide. These trends can be explained by demographic truncation of the population’s age structure, phenotypic plasticity in maturation arising through density-dependent growth, fisheries-induced evolution favoring faster-growing or earlier-maturing fish, or a combination of these processes. Here, we use a multitrait eco-evolutionary model to assess the capacity of these processes to reproduce 74 y of historical data on age and length at maturation in northeast Arctic cod, while mimicking the stock’s historical harvesting regime. Our results show that model predictions critically depend on the assumed density dependence of growth: when this is weak, life history evolution might be necessary to prevent stock collapse, whereas when a stronger density dependence estimated from recent data is used, the role of evolution in explaining fisheries-induced trait changes is diminished. Our integrative analysis of density-dependent growth, multitrait evolution, and stock-specific time series data underscores the importance of jointly considering evolutionary and ecological processes, enabling a more comprehensive perspective on empirically observed stock dynamics than previous studies could provide. PMID:27940913

  18. MMTV-induced pregnancy-dependent mammary tumors : early history and new perspectives.

    PubMed

    Kordon, Edith C

    2008-09-01

    Almost 60 years ago, Foulds carefully described for the first time a particular type of mouse mammary tumor that appeared in the glands of pregnant females and disappeared shortly after delivery. Since then, the attention that researchers paid to the Mouse Mammary Tumor Virus (MMTV)-induced pregnancy-dependent tumors has not vanished through the years. This was because the information obtained from mice carrying MMTV variants that were able to induce pregnancy-dependent tumors was meaningful for studying different aspects of mammary tumor biology. In addition, mice infected with these viral variants provided some of the few chances to use fully hormone-dependent estrogen receptor positive breast cancer models in the mouse. In the analysis of the association between tumor morphology and behavior, the mechanisms underlying progression towards autonomy, the impact of different genes during cancer initiation and development, and the relevance of host genetic background for tumor incidence and hormone-dependence, mouse strains carrying these MMTV variants have been very important tools that could not have been replaced with any other available model. The goal of this article is to provide a succinct chronicle of the experiments and observations made in the MMTV-induced pregnancy-dependent models that most significantly contributed to the mouse mammary tumor biology field. In addition, the possibility to use these MMTV variants as alternative models for analyzing mammary tumor stem cells and pregnancy-associated breast cancer in women is discussed.

  19. Sweet preference, sugar addiction and the familial history of alcohol dependence: shared neural pathways and genes.

    PubMed

    Fortuna, Jeffrey L

    2010-06-01

    Contemporary research has shown that a high number of alcohol-dependent and other drug-dependent individuals have a sweet preference, specifically for foods with a high sucrose concentration. Moreover, both human and animal studies have demonstrated that in some brains the consumption of sugar-rich foods or drinks primes the release of euphoric endorphins and dopamine within the nucleus accumbens, in a manner similar to some drugs of abuse. The neurobiological pathways of drug and "sugar addiction" involve similar neural receptors, neurotransmitters, and hedonic regions in the brain. Craving, tolerance, withdrawal and sensitization have been documented in both human and animal studies. In addition, there appears to be cross sensitization between sugar addiction and narcotic dependence in some individuals. It has also been observed that the biological children of alcoholic parents, particularly alcoholic fathers, are at greater risk to have a strong sweet preference, and this may manifest in some with an eating disorder. In the last two decades research has noted that specific genes may underlie the sweet preference in alcohol- and drug-dependent individuals, as well as in biological children of paternal alcoholics. There also appears to be some common genetic markers between alcohol dependence, bulimia, and obesity, such as the A1 allele gene and the dopamine 2 receptor gene.

  20. Associations between psychedelic use, abuse, and dependence and lifetime panic attack history in a representative sample.

    PubMed

    Bonn-Miller, Marcel O; Bernstein, Amit; Sachs-Ericsson, Natalie; Schmidt, Norman B; Zvolensky, Michael J

    2007-01-01

    The present investigation evaluated the associations between lifetime psychedelic use, abuse, and dependence and panic attacks. The study consisted of a representative epidemiological sample from a state wide survey of the Colorado general adult population (n=4745; 52% female). Consistent with prediction, after controlling for theoretically relevant variables, psychedelic abuse and dependence, but not use, were significantly related to an increased lifetime risk of panic attacks. The results are discussed in terms of better understanding the role of psychedelic use in relation to the occurrence of panic attacks.

  1. Vital capacities in acute and chronic airway obstruction: dependence on flow and volume histories.

    PubMed

    Brusasco, V; Pellegrino, R; Rodarte, J R

    1997-06-01

    The aim of this study was to investigate whether measurements of vital capacity (VC) are affected by the direction of the manoeuvre (inspiratory vs expiratory) and by the rate of expiratory flow. The study was performed on 25 individuals with chronic airway obstruction (CAO) and a forced expiratory volume in one second (FEV1) (expressed in standardized residuals (SR)) of -2.0+/-1.4 SD (CAO group), and 10 asthmatic subjects with methacholine (MCh)-induced bronchoconstriction (FEV1 -23+/-1.02 SR) (MCh group). VCs were measured during fast inspiration following both slow (FIVCse) and forced (FIVCfe) expiration from end-tidal inspiration to residual volume (RV), and during slow (EVC) or forced (FVC) expiration from total lung capacity (TLC). In the CAO group, FVC was the smallest volume (3.75+/-1.03 L) and significantly different from the other three estimates of VC; FIVCse (4.03+/-0.91 L) was the largest volume and significantly different from FVC and FIVCfe (3.83+/-0.98 L). In the MCh group, FVC (4.16+/-0.94 L) and EVC (4.19+/-0.89 L) were the largest volumes, although only the difference between FVC and FIVCfe (3.76+/-0.81 L) reached statistical significance. These data suggest that both flow and volume histories contribute to decreased vital capacities during bronchoconstriction. However, whereas increasing expiratory flow always tends to decrease vital capacity, the volume history of full inflation has different effects in chronic and acute bronchoconstriction, probably due to different effects on airway calibre. These results stress the importance of using standardized manoeuvres in order to obtain comparable values of vital capacity.

  2. A short history of cGMP, guanylyl cyclases, and cGMP-dependent protein kinases.

    PubMed

    Kots, Alexander Y; Martin, Emil; Sharina, Iraida G; Murad, Ferid

    2009-01-01

    Here, we review the early studies on cGMP, guanylyl cyclases, and cGMP-dependent protein kinases to facilitate understanding of development of this exciting but complex field of research encompassing pharmacology, biochemistry, physiology, and molecular biology of these important regulatory molecules.

  3. A Short History of cGMP, Guanylyl Cyclases, and cGMP-Dependent Protein Kinases

    PubMed Central

    Kots, Alexander Y.; Martin, Emil; Sharina, Iraida G.

    2014-01-01

    Here, we review the early studies on cGMP, guanylyl cyclases, and cGMP-dependent protein kinases to facilitate understanding of development of this exciting but complex field of research encompassing pharmacology, biochemistry, physiology, and molecular biology of these important regulatory molecules. PMID:19089322

  4. State-dependent life history models in a changing (and regulated) environment: steelhead in the California Central Valley

    PubMed Central

    Satterthwaite, William H; Beakes, Michael P; Collins, Erin M; Swank, David R; Merz, Joseph E; Titus, Robert G; Sogard, Susan M; Mangel, Marc

    2010-01-01

    We use a state dependent life history model to predict the life history strategies of female steelhead trout (Oncorhynchus mykiss) in altered environments. As a case study of a broadly applicable approach, we applied this model to the American and Mokelumne Rivers in central California, where steelhead are listed as threatened. Both rivers have been drastically altered, with highly regulated flows and translocations that may have diluted local adaptation. Nevertheless, evolutionary optimization models could successfully predict the life history displayed by fish on the American River (all anadromous, with young smolts) and on the Mokelumne River (a mix of anadromy and residency). The similar fitness of the two strategies for the Mokelumne suggested that a mixed strategy could be favored in a variable environment. We advance the management utility of this framework by explicitly modeling growth as a function of environmental conditions and using sensitivity analyses to predict likely evolutionary endpoints under changed environments. We conclude that the greatest management concern with respect to preserving anadromy is reduced survival of emigrating smolts, although large changes in freshwater survival or growth rates are potentially also important. We also demonstrate the importance of considering asymptotic size along with maximum growth rate. PMID:25567921

  5. What shall I do now? State-dependent variations of life-history traits with aging in Wandering Albatrosses.

    PubMed

    Pardo, Deborah; Barbraud, Christophe; Weimerskirch, Henri

    2014-02-01

    Allocation decisions depend on an organism's condition which can change with age. Two opposite changes in life-history traits are predicted in the presence of senescence: either an increase in breeding performance in late age associated with terminal investment or a decrease due to either life-history trade-offs between current breeding and future survival or decreased efficiency at old age. Age variation in several life-history traits has been detected in a number of species, and demographic performances of individuals in a given year are influenced by their reproductive state the previous year. Few studies have, however, examined state-dependent variation in life-history traits with aging, and they focused mainly on a dichotomy of successful versus failed breeding and non-breeding birds. Using a 50-year dataset on the long-lived quasi-biennial breeding wandering albatross, we investigated variations in life-history traits with aging according to a gradient of states corresponding to potential costs of reproduction the previous year (in ascending order): non-breeding birds staying at sea or present at breeding grounds, breeding birds that failed early, late or were successful. We used multistate models to study survival and decompose reproduction into four components (probabilities of return, breeding, hatching, and fledging), while accounting for imperfect detection. Our results suggest the possible existence of two strategies in the population: strict biennial breeders that exhibited almost no reproductive senescence and quasi-biennial breeders that showed an increased breeding frequency with a strong and moderate senescence on hatching and fledging probabilities, respectively. The patterns observed on survival were contrary to our predictions, suggesting an influence of individual quality rather than trade-offs between reproduction and survival at late ages. This work represents a step further into understanding the evolutionary ecology of senescence and its

  6. What shall I do now? State-dependent variations of life-history traits with aging in Wandering Albatrosses

    PubMed Central

    Pardo, Deborah; Barbraud, Christophe; Weimerskirch, Henri

    2014-01-01

    Allocation decisions depend on an organism's condition which can change with age. Two opposite changes in life-history traits are predicted in the presence of senescence: either an increase in breeding performance in late age associated with terminal investment or a decrease due to either life-history trade-offs between current breeding and future survival or decreased efficiency at old age. Age variation in several life-history traits has been detected in a number of species, and demographic performances of individuals in a given year are influenced by their reproductive state the previous year. Few studies have, however, examined state-dependent variation in life-history traits with aging, and they focused mainly on a dichotomy of successful versus failed breeding and non-breeding birds. Using a 50-year dataset on the long-lived quasi-biennial breeding wandering albatross, we investigated variations in life-history traits with aging according to a gradient of states corresponding to potential costs of reproduction the previous year (in ascending order): non-breeding birds staying at sea or present at breeding grounds, breeding birds that failed early, late or were successful. We used multistate models to study survival and decompose reproduction into four components (probabilities of return, breeding, hatching, and fledging), while accounting for imperfect detection. Our results suggest the possible existence of two strategies in the population: strict biennial breeders that exhibited almost no reproductive senescence and quasi-biennial breeders that showed an increased breeding frequency with a strong and moderate senescence on hatching and fledging probabilities, respectively. The patterns observed on survival were contrary to our predictions, suggesting an influence of individual quality rather than trade-offs between reproduction and survival at late ages. This work represents a step further into understanding the evolutionary ecology of senescence and its

  7. High-dose nicotine patch therapy for smokers with a history of alcohol dependence: 36-week outcomes.

    PubMed

    Kalman, David; Kahler, Christopher W; Garvey, Arthur J; Monti, Peter M

    2006-04-01

    This study reports findings from an investigation of the efficacy of high-dose nicotine patch (NP) therapy for heavy smokers with a history of alcohol dependence. One hundred thirty participants were randomly assigned to 42 or 21 mg of transdermal nicotine. Follow-up assessments were conducted at 4, 12, 24, and 36 weeks. Differences between dose conditions were nonsignificant, although, unexpectedly, outcomes favored participants in the 21-mg NP condition. Nicotine abstinence rates in the 21- and 42-mg NP conditions on Week 36 follow-up were 16.9% and 9.2%, respectively. Patch condition did not interact with severity of nicotine dependence. However, nicotine abstinence at follow-up was related to a longer length of alcohol abstinence. No evidence was found for better outcomes as a function of the percentage of baseline cotinine replaced by NPs. Future research should focus primarily on investigating ways to improve smoking quit rates for smokers in early alcohol recovery.

  8. History dependence of the magnetic properties of single-crystal Fe1 -xCoxSi

    NASA Astrophysics Data System (ADS)

    Bauer, A.; Garst, M.; Pfleiderer, C.

    2016-06-01

    We report the magnetization, ac susceptibility, and specific heat of optically float-zoned single crystals of Fe1 -xCoxSi , 0.20 ≤x ≤0.50 . We determine the magnetic phase diagrams for all major crystallographic directions and cooling histories. After zero-field cooling, the phase diagrams resemble that of the archetypal stoichiometric cubic chiral magnet MnSi. Besides the helical and conical state, we observe a pocket of skyrmion lattice phase just below the helimagnetic ordering temperature. At the phase boundaries between these states evidence for slow dynamics is observed. When the sample is cooled in small magnetic fields, the phase pocket of skyrmion lattice may persist metastably down to the lowest temperatures. Taken together with the large variation in the transition temperatures, transition fields, and helix wavelength as a function of the composition, this hysteresis identifies Fe1 -xCoxSi as an ideal material for future experiments exploring, for instance, the topological unwinding of the skyrmion lattice.

  9. Increased dependence of action selection on recent motor history in Parkinson's disease.

    PubMed

    Helmich, Rick C; Aarts, Esther; de Lange, Floris P; Bloem, Bastiaan R; Toni, Ivan

    2009-05-13

    It is well known that the basal ganglia are involved in switching between movement sequences. Here we test the hypothesis that this contribution is an instance of a more general role of the basal ganglia in selecting actions that deviate from the context defined by the recent motor history, even when there is no sequential structure to learn or implement. We investigated the effect of striatal dopamine depletion [in Parkinson's disease (PD)] on the ability to switch between independent action plans. PD patients with markedly lateralized signs performed a hand laterality judgment task that involved action selection of their most and least affected hand. Trials where patients selected the same (repeat) or the alternative (switch) hand as in a previous trial were compared, and this was done separately for the most and least affected hand. Behaviorally, PD patients showed switch-costs that were specific to the most affected hand and that increased with disease severity. Functional magnetic resonance imaging (fMRI) showed that this behavioral effect was related to the state of the frontostriatal system: as disease severity increased, contributions of the basal ganglia to the selection process and their effective connectivity with the medial frontal cortex (MFC) decreased, whereas involvement of the MFC increased. We conclude that the basal ganglia are important for rapidly switching toward novel motor plans even when there is no sequential structure to learn or implement. The enhanced MFC activity may result either from reduced focusing abilities of the basal ganglia or from compensatory processes.

  10. The Star-Formation History Dependence of X-ray Binary Formation: Clues from M51

    NASA Astrophysics Data System (ADS)

    Lehmer, Bret; Eufrasio, Rafael T.; Zezas, Andreas; Basu-Zych, Antara; Fragos, Tassos; Hornschemeier, Ann E.; Kalogera, Vassiliki; Ptak, Andrew; Tzanavaris, Panayiotis; Yukita, Mihoko

    2017-08-01

    Recently, we have found, in the Chandra Deep Field-South, that the emission from X-ray binary (XRB) populations in galaxies evolves significantly with cosmic time, most likely due to changes in the physical properties of galaxies like star-formation rate, stellar mass, stellar age, and metallicity. However, it has been challenging to directly show that these same physical properties are connected to XRB populations using data from nearby galaxies. We present a new technique for empirically calibrating how X-ray binary (XRB) populations evolve following their formation in a variety of environments. We first utilize detailed spectral energy distribution modeling of far-UV to far-IR broadband data of the nearby (~8.5 Mpc) face-on spiral galaxies M51 to construct a map of its star-formation history (SFH) on subgalactic scales. Using Chandra data, we then identify the locations of the XRBs and correlate their formation frequencies with local SFH, as characterized by the mean mass-weighted stellar age. In this talk, I will show promising first constraints on how the shape and normalization of XRB luminosity function evolves with time based on our analysis. I further discuss how expanding our sample to an archival sample of ~25 face-on spirals will lead to a detailed empirical timeline for how XRBs form and evolve in a variety of environments and throughout cosmic time.

  11. Effect of yohimbine on reinstatement of operant responding in rats is dependent on cue contingency but not food reward history

    PubMed Central

    Chen, Yu-Wei; Fiscella, Kimberly A.; Bacharach, Samuel Z.; Tanda, Gianluigi; Shaham, Yavin; Calu, Donna J.

    2014-01-01

    Yohimbine is an alpha-2 adrenoceptor antagonist that has been used in numerous studies as a pharmacological stressor in rodents, monkeys, and humans. Recently, yohimbine has become the most common stress manipulation in studies on reinstatement of drug and food seeking. However, the wide range of conditions under which yohimbine promotes reward seeking is significantly greater than that of stressors like intermittent footshock. Here we addressed two fundamental questions regarding yohimbine’s effect on reinstatement of reward seeking: (1) whether the drug’s effect on operant responding is dependent on previous reward history or cue contingency, and (2) whether yohimbine is aversive or rewarding under conditions typically used in reinstatement studies. We also used in vivo microdialysis to determine yohimbine’s effect on dopamine levels in nucleus accumbens (NAc) and medial prefrontal cortex (mPFC). We found that the magnitude of yohimbine-induced (0.5, 1.0, 2.0 mg/kg) operant responding during the reinstatement tests was critically dependent on the contingency between lever-pressing and discrete tone-light cue delivery but not the previous history with food reward during training. We also found that yohimbine (2 mg/kg) did not cause conditioned place aversion. Finally, we found that yohimbine modestly increased dopamine levels in mPFC but not NAc. Results suggest that yohimbine’s effects on operant responding in reinstatement studies are likely independent of the history of contingent self-administration of food or drug rewards and may not be related to the commonly assumed stress-like effects of yohimbine. PMID:25065697

  12. Effect of yohimbine on reinstatement of operant responding in rats is dependent on cue contingency but not food reward history.

    PubMed

    Chen, Yu-Wei; Fiscella, Kimberly A; Bacharach, Samuel Z; Tanda, Gianluigi; Shaham, Yavin; Calu, Donna J

    2015-07-01

    Yohimbine is an alpha-2 adrenoceptor antagonist that has been used in numerous studies as a pharmacological stressor in rodents, monkeys and humans. Recently, yohimbine has become the most common stress manipulation in studies on reinstatement of drug and food seeking. However, the wide range of conditions under which yohimbine promotes reward seeking is significantly greater than that of stressors like intermittent footshock. Here, we addressed two fundamental questions regarding yohimbine's effect on reinstatement of reward seeking: (1) whether the drug's effect on operant responding is dependent on previous reward history or cue contingency, and (2) whether yohimbine is aversive or rewarding under conditions typically used in reinstatement studies. We also used in vivo microdialysis to determine yohimbine's effect on dopamine levels in nucleus accumbens (NAc) and medial prefrontal cortex (mPFC). We found that the magnitude of yohimbine-induced (0.5, 1.0, 2.0 mg/kg) operant responding during the reinstatement tests was critically dependent on the contingency between lever pressing and discrete tone-light cue delivery but not the previous history with food reward during training. We also found that yohimbine (2 mg/kg) did not cause conditioned place aversion. Finally, we found that yohimbine modestly increased dopamine levels in mPFC but not NAc. Results suggest that yohimbine's effects on operant responding in reinstatement studies are likely independent of the history of contingent self-administration of food or drug rewards and may not be related to the commonly assumed stress-like effects of yohimbine.

  13. Photoperiod history-dependent responses to intermediate day lengths engage hypothalamic iodothyronine deiodinase type III mRNA expression.

    PubMed

    Kampf-Lassin, August; Prendergast, Brian J

    2013-04-15

    Perihypothalamic thyroid hormone signaling features prominently in the seasonal control of reproductive physiology. Triiodothyronine (T(3)) signaling stimulates gonadal development, and decrements in T(3) signaling are associated with gonadal regression. Type 3 iodothyronine deiodinase (DIO3) converts the prohormone thyroxine (T(4)) into biologically inactive 3,3',5'-triiodothyronine, and in long-day breeding Siberian hamsters exposure to long (LD) and short (SD) photoperiods, respectively, inhibit and stimulate hypothalamic dio3 mRNA expression. Reproductive responses to intermediate-duration photoperiods (IntD) occur in a history-dependent manner; IntDs are interpreted as inhibitory only when preceded by longer photoperiods. Because dio3 expression has only been evaluated under LD or SD photoperiods, it is not known whether hypothalamic dio3 encodes absolute photoperiod duration or the reproductive interpretation of photoperiod. Male Siberian hamsters with and without a prior history of LD were exposed to IntD photoperiods, and hypothalamic dio3 mRNA expression was measured 6 wk later. Hamsters with a LD photoperiod history exhibited gonadal regression in IntD and a marked upregulation of hypothalamic dio3 expression, whereas in hamsters without prior exposure to LD, gonadal responses to IntD were absent, and dio3 expression remained low. Patterns of deiodinase expression in hamsters maintained in chronic IntD photoperiods did not appear to reflect feedback effects of gonadal status. Hypothalamic expression of dio3 does not exclusively reflect ambient photoperiod, but rather the context-dependent reproductive interpretation of photoperiod. Neuroendocrine mechanisms that compare current and prior photoperiods, which permit detection of directional changes in day length, occur either upstream, or at the level, of hypothalamic dio3 expression.

  14. Factor structure of PTSD symptoms in opioid-dependent patients rating their overall trauma history.

    PubMed

    Reddy, Madhavi K; Anderson, Bradley J; Liebschutz, Jane; Stein, Michael D

    2013-10-01

    The current standard for posttraumatic stress disorder (PTSD) diagnosis is a 3-factor model (re-experiencing, avoidance, and hyperarousal). Two 4-factor models of PTSD, the emotional numbing model (re-experiencing, avoidance, emotional numbing, and hyperarousal) and the dysphoria model (re-experiencing, avoidance, dysphoria, and hyperarousal), have considerable empirical support in the extant literature. However, a newer 5-factor model of PTSD has been introduced that is receiving interest. The 5-factor model differs from the four-factor models in its placement of three symptoms (irritability, sleep disturbance, and concentration difficulties) into a separate cluster termed dysphoric arousal. We empirically compared the theoretical factor structures of 3-, 4-, and 5-factor models of PTSD symptoms to find the best fitting model in a sample of opioid-dependent hospitalized patients. Confirmatory factor analyses were conducted on the 17 self-reported PTSD symptoms of the Posttraumatic Checklist - Civilian Version (PCL-C) in a sample of 151 men and women with opioid dependence. Both four-factor models fit the observed data better than the three-factor model of PTSD; the dysphoria model was preferred to the emotional numbing model in this sample. The recently introduced five-factor model fit the observed data better than either four factor model. PTSD is a heterogeneous disorder comprised of symptoms of re-experiencing, avoidance, numbing, and dysphoria. Three symptoms, irritability, sleep disturbance, and concentration difficulties, may represent a unique latent construct separate from these four symptom clusters in opioid-dependent populations who have experienced traumatic events. Published by Elsevier Ireland Ltd.

  15. The mass dependence of star formation histories in barred spiral galaxies

    NASA Astrophysics Data System (ADS)

    Carles, Christian; Martel, Hugo; Ellison, Sara L.; Kawata, Daisuke

    2016-11-01

    We performed a series of 29 gas dynamical simulations of disc galaxies, barred and unbarred, with various stellar masses, to study the impact of the bar on star formation history. Unbarred galaxies evolve very smoothly, with a star formation rate (SFR) that varies by at most a factor of 3 over a period of 2 Gyr. The evolution of barred galaxies is much more irregular, especially at high stellar masses. In these galaxies, the bar drives a substantial amount of gas towards the centre, resulting in a high SFR, and producing a starburst in the most massive galaxies. Most of the gas is converted into stars, and gas exhaustion leads to a rapid drop of star formation after the starburst. In massive barred galaxies (stellar mass M_{*}>2× 10^{10} M_{⊙}) the large amount of gas funnelled towards the centre is completely consumed by the starburst, while in lower mass barred galaxies it is only partially consumed. Gas concentration is thus higher in lower mass barred galaxies than it is in higher mass ones. Even though unbarred galaxies funnelled less gas towards their centre, the lower SFR allows this gas to accumulate. At late times, the star formation efficiency is higher in barred galaxies than unbarred ones, enabling these galaxies to maintain a higher SFR with a smaller gas supply. Several properties, such as the global SFR, central SFR, or central gas concentration, vary monotonically with time for unbarred galaxies, but not for barred galaxies. Therefore one must be careful when comparing barred and unbarred galaxies that share one observational property, since these galaxies might be at very different stages of their respective evolution.

  16. Voluntary exercise and its effects on body composition depend on genetic selection history.

    PubMed

    Nehrenberg, Derrick L; Hua, Kunjie; Estrada-Smith, Daria; Garland, Theodore; Pomp, Daniel

    2009-07-01

    Little is known about how genetic variation affects the capacity for exercise to change body composition. We examined the extent to which voluntary exercise alters body composition in several lines of selectively bred mice compared to controls. Lines studied included high runner (HR) (selected for high wheel running), M16 (selected for rapid weight gain), Institute of Cancer Research (ICR) (randomly bred as control for M16), M16i (an inbred line derived from M16), HE (selected for high percentage of body fat while holding body weight constant), LF (selected for low percentage of body fat), C57BL/6J (common inbred line), and the F1 between HR and C57BL/6J. Body weight and body fat were recorded before and after 6 days of free access to running wheels in males and females that were individually caged. Total food intake was measured during this 6-day period. All pre- and postexercise measures showed significant strain effects. While HR mice predictably exercised at higher levels, all other selection lines had decreased levels of wheel running relative to ICR. The HR x B6 F1 ran at similar levels to HR demonstrating complete dominance for voluntary exercise. Also, all strains lost body fat after exercise, but the relationships between exercise and changes in percent body were not uniform across genotypes. These results indicate that there is significant genetic variation for voluntary exercise and its effects on body composition. It is important to carefully consider genetic background and/or selection history when using mice to model effects of exercise on body composition, and perhaps, other complex traits as well.

  17. Neural correlates of impulsive aggressive behavior in subjects with a history of alcohol dependence.

    PubMed

    Kose, Samet; Steinberg, Joel L; Moeller, F Gerard; Gowin, Joshua L; Zuniga, Edward; Kamdar, Zahra N; Schmitz, Joy M; Lane, Scott D

    2015-04-01

    Alcohol-related aggression is a complex and problematic phenomenon with profound public health consequences. We examined neural correlates potentially moderating the relationship between human aggressive behavior and chronic alcohol use. Thirteen subjects meeting DSM-IV criteria for past alcohol-dependence in remission (AD) and 13 matched healthy controls (CONT) participated in an fMRI study adapted from a laboratory model of human aggressive behavior (Point Subtraction Aggression Paradigm, or PSAP). Blood oxygen level dependent (BOLD) activation was measured during bouts of operationally defined aggressive behavior, during postprovocation periods, and during monetary-reinforced behavior. Whole brain voxelwise random-effects analyses found group differences in brain regions relevant to chronic alcohol use and aggressive behavior (e.g., emotional and behavioral control). Behaviorally, AD subjects responded on both the aggressive response and monetary response options at significantly higher rates than CONT. Whole brain voxelwise random-effects analyses revealed significant group differences in response to provocation (monetary subtractions), with CONT subjects showing greater activation in frontal and prefrontal cortex, thalamus, and hippocampus. Collapsing data across all subjects, regression analyses of postprovocation brain activation on aggressive response rate revealed significant positive regression slopes in precentral gyrus and parietal cortex; and significant negative regression slopes in orbitofrontal cortex, prefrontal cortex, caudate, thalamus, and middle temporal gyrus. In these collapsed analyses, response to provocation and aggressive behavior were associated with activation in brain regions subserving inhibitory and emotional control, sensorimotor integration, and goal directed motor activity.

  18. Neural Correlates of Impulsive Aggressive Behavior in Subjects With a History of Alcohol Dependence

    PubMed Central

    Kose, Samet; Steinberg, Joel L.; Moeller, F. Gerard; Gowin, Joshua L.; Zuniga, Edward; Kamdar, Zahra N.; Schmitz, Joy M.; Lane, Scott D.

    2015-01-01

    Alcohol-related aggression is a complex and problematic phenomenon with profound public health consequences. We examined neural correlates potentially moderating the relationship between human aggressive behavior and chronic alcohol use. Thirteen subjects meeting DSM–IV criteria for past alcohol-dependence in remission (AD) and 13 matched healthy controls (CONT) participated in an fMRI study adapted from a laboratory model of human aggressive behavior (Point Subtraction Aggression Paradigm, or PSAP). Blood oxygen level dependent (BOLD) activation was measured during bouts of operationally defined aggressive behavior, during postprovocation periods, and during monetary-reinforced behavior. Whole brain voxelwise random-effects analyses found group differences in brain regions relevant to chronic alcohol use and aggressive behavior (e.g., emotional and behavioral control). Behaviorally, AD subjects responded on both the aggressive response and monetary response options at significantly higher rates than CONT. Whole brain voxelwise random-effects analyses revealed significant group differences in response to provocation (monetary subtractions), with CONT subjects showing greater activation in frontal and prefrontal cortex, thalamus, and hippocampus. Collapsing data across all subjects, regression analyses of postprovocation brain activation on aggressive response rate revealed significant positive regression slopes in precentral gyrus and parietal cortex; and significant negative regression slopes in orbitofrontal cortex, prefrontal cortex, caudate, thalamus, and middle temporal gyrus. In these collapsed analyses, response to provocation and aggressive behavior were associated with activation in brain regions subserving inhibitory and emotional control, sensorimotor integration, and goal directed motor activity. PMID:25664566

  19. Antisocial personality disorder in Turkish substance dependent patients and its relationship with anxiety, depression and a history of childhood abuse.

    PubMed

    Evren, Cuneyt; Kural, Sevil; Erkiran, Murat

    2006-01-01

    The prevalence of antisocial personality disorder (ASPD) in treatment-seeking Turkish substance dependent patients and the relationship of ASPD with clinical characteristics were studied. Participants were 132 inpatients with substance dependence according to the Structured Clinical Interview for DSM-IV (SCID-I), Turkish version. The clinician applied a semi-structured socio-demographic form, SCID-I, SCID-II, Childhood Abuse and Neglect Questionnaire (CANQ), Michigan Alcoholism Screening Test (MAST), Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI). Among the 132 substance dependent patients, 31 (23.5%) had ASPD diagnosis and 56 (42.4%) had no personality disorder or personality traits. Rate of childhood physical abuse, childhood verbal abuse, childhood neglect, suicide attempt history, self-destructive behavior and lifetime major depression were higher among patients with ASPD. Also mean scores of BDI, BAI and MAST were higher among patients with ASPD. The high rate of ASPD found among Turkish substance dependent patients suggests that special attention must be paid to identify ASPD in this group. Findings in this study showed that there is an association between ASPD and childhood abuse, lifetime major depression and severity of substance use.

  20. History of suicide attempt in male substance-dependent inpatients and relationship to borderline personality features, anger, hostility and aggression.

    PubMed

    Evren, Cuneyt; Cinar, Ozgul; Evren, Bilge; Celik, Selime

    2011-11-30

    The aim of this study was to investigate the relationship between severity of borderline personality features and history of suicide attempt (HSA) in male substance-dependent inpatients and the effect of anger, hostility and aggression on this relationship. Further, the effect of some variables that may be related to suicide and/or borderline personality, such as age at inception of regular substance use, substance of dependence (alcohol/drug), depression, and both state and trait anxiety, were controlled. Participants were 200 consecutively admitted male substance-dependent inpatients. Patients were investigated with the Borderline Personality Inventory (BPI), the Buss-Perry Aggression Questionnaire (AQ), the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory (STAI). Among substance-dependent inpatients, 33.0% (n=66) were identified as the group with HSA. Mean scores employment status, marital status and duration of education did not differ between groups, whereas current age and age at onset of regular substance use were lower in group with HSA. Mean scores of BPI, AQ and its subscales (anger, hostility and physical/verbal aggression), BDI and STAI were higher in the HSA group. In addition, the rates of drug dependency and borderline personality disorder were higher in this group. The severity of borderline personality symptoms was highly correlated with subscales of the AQ, depression and anxiety, whereas it was negatively correlated with age at onset of regular substance use. The severity of anger and borderline personality features predicted HSA in the logistic regression model. Results suggest that, to reduce the risk of suicide attempt among substance-dependent patients, the feeling of anger must be the target of evaluation and treatment among those with borderline personality features.

  1. Marginal rigidity and history dependence in packings of attractive athermal emulsions

    NASA Astrophysics Data System (ADS)

    Bargteil, Dylan; Pontani, Lea-Laetitia; Brujic, Jasna

    2014-03-01

    The geometry and stress through particulate packings depends on the method of preparation and the interaction potential between the particles. Previously, we discovered that creaming frictionless, athermal emulsions with a short-range depletion attraction leads to an initial increase in the packing density above random close packing, followed by a monotonic decrease in density (Jorjadze et al, PNAS, 2011). This decrease is because the attractive force stabilizes loose voids, thus reducing the average coordination number, , of the packing. In order to understand the mechanism of packing creation, we investigate whether the final density is influenced by the polydispersity or the initial volume fraction of droplets, as it is in frictional packings. Finally, we compress the attractive packings by centrifugation to probe the scaling laws of pressure versus density and and compare them with those found in repulsive packings (Jorjadze et al, PRL, 2013).

  2. Pharmacological pain control for human immunodeficiency virus—infected adults with a history of drug dependence

    PubMed Central

    Basu, Sanjay; Bruce, R. Douglas; Barry, Declan T.; Altice, Frederick L.

    2007-01-01

    Clinicians treating human immunodeficiency virus (HIV)-infected patients with substance use disorders often face the challenge of managing patients' acute or chronic pain conditions while keeping in mind the potential dangers of prescription opiate dependence. In this clinical review, we critically appraise the existing data concerning barriers to appropriate treatment of pain among HIV-infected patients with substance use disorders. We then analyze published studies concerning the choice of pharmacological pain control regimens for acute and chronic pain conditions in HIV-infected patients, keeping in mind HIV-specific issues related to drug interactions and substance use disorders. We summarize this information in the form of flowcharts for physicians approaching HIV-infected patients who present with complaints of pain, providing evidence-based guidance for the structuring of pain management services and for addressing aberrant drug-taking behaviors. PMID:17481463

  3. Temperature-dependent structural variability of RNAs: spliced leader RNAs and their evolutionary history.

    PubMed

    Marz, Manja; Vanzo, Nathalie; Stadler, Peter F

    2010-02-01

    The structures attained by RNA molecules depend not only on their sequence but also on environmental parameters such as their temperature. So far, this effect has been largely neglected in bioinformatics studies. Here, we show that structural comparisons can be facilitated and more coherent structural models can be obtained when differences in environmental parameters are taken into account. We re-evaluate the secondary structures of the spliced leader (SL) RNAs from the seven eukaryotic phyla in which SL RNA trans-splicing has been described. Adjusting structure prediction to the natural growth temperatures and considering energetically similar secondary structures, we observe striking similarities among Euglenida, Kinetoplastida, Dinophyceae, Cnidaria, Rotifera, Nematoda, Platyhelminthes, and Tunicata that cannot be explained easily by the independent innovation of SL RNAs in each of these phyla. Supplementary Table is available at http://www.worldscinet.com/jbcb/.

  4. Density ratio dependence of Rayleigh-Taylor mixing for sustained and impulsive acceleration histories

    SciTech Connect

    Dimonte, Guy; Schneider, Marilyn

    2000-02-01

    The turbulent Rayleigh-Taylor instability is investigated over a comprehensive range of fluid density ratio (R)1.3{<=}R{<=}50 [0.15{<=}A=(R-1)/(R+1){<=}0.96] and different acceleration histories g(t) using the Linear Electric Motor. The mixing layer is diagnosed with backlit photography and laser-induced fluorescence. For a constant acceleration, the bubble (2) and spike (1) amplitudes are found to increase as h{sub i}={alpha}{sub i}Agt{sup 2} with {alpha}{sub 2}{approx}0.05{+-}0.005 and {alpha}{sub 1}{approx}{alpha}{sub 2}R{sup D{}sub {alpha}} with D{sub {alpha}}{approx}0.33{+-}0.05. For temporally varying accelerations Ag(t)>0, this can be generalized to h{sub i}=2{alpha}{sub i}AS using S=[{integral}(sq root)(g)dt]{sup 2}/2 rather than the displacement Z={integral}{integral}gdt{sup '} dt. For impulsive accelerations, S remains constant during the coast phase and the amplitudes obey a power law h{sub i}{approx}t{sup {theta}}{sup {}sub i} with {theta}{sub 2}{approx}0.25{+-}0.05 and {theta}{sub 1}{approx}{theta}{sub 2}R{sup D{}sub {theta}} with D{sub {theta}}{approx}0.21{+-}0.05. These values of D{sub {alpha}} and D{sub {theta}} compare favorably with numerical simulations and mix models. The average diameter at the mixing front for bubbles is found to increase as d{sub 2}{approx}h{sub 2}(1+A)/4 in qualitative agreement with ''merger'' models, but the associated dh{sub i}/dt is two times larger than the terminal velocity of an isolated bubble. The spikes become relatively narrow at large R, yet they still grow as gt{sup 2}. (c) 2000 American Institute of Physics.

  5. Herbivores sculpt leaf traits differently in grasslands depending on life form and land-use histories.

    PubMed

    Firn, Jennifer; Schütz, Martin; Nguyen, Huong; Risch, Anita C

    2017-01-01

    Vertebrate and invertebrate herbivores alter plant communities directly by selectively consuming plant species; and indirectly by inducing morphological and physiological changes to plant traits that provide competitive or survivorship advantages to some life forms over others. Progressively excluding aboveground herbivore communities (ungulates, medium and small sized mammals, invertebrates) over five growing seasons, we explored how leaf morphology (specific leaf area or SLA) and nutrition (nitrogen, carbon, phosphorous, potassium, sodium, and calcium) of different plant life forms (forbs, legumes, grasses, sedges) correlated with their dominance. We experimented in two subalpine grassland types with different land-use histories: (1) heavily grazed, nutrient-rich, short-grass vegetation and (2) lightly grazed, lower nutrient tall-grass vegetation. We found differences in leaf traits between treatments where either all herbivores were excluded or all herbivores were present, showing the importance of considering the impacts of both vertebrates and invertebrates on the leaf traits of plant species. Life forms responses to the progressive exclusion of herbivores were captured by six possible combinations: (1) increased leaf size and resource use efficiency (leaf area/nutrients) where lower nutrient levels are invested in leaf construction, but a reduction in the number of leaves, for example, forbs in both vegetation types, (2) increased leaf size and resource use efficiency, for example, legumes in short grass, (3) increased leaf size but a reduction in the number of leaves, for example, legumes in the tall grass, (4) increased number of leaves produced and increased resource use efficiency, for example, grasses in the short grass, (5) increased resource use efficiency of leaves only, for example, grasses and sedges in the tall grass, and (6) no response in terms of leaf construction or dominance, for example, sedges in the short grass. Although we found multiple

  6. Programming of left hand exploits task set but that of right hand depends on recent history.

    PubMed

    Tang, Rixin; Zhu, Hong

    2017-07-01

    There are many differences between the left hand and the right hand. But it is not clear if there is a difference in programming between left hand and right hand when the hands perform the same movement. In current study, we carried out two experiments to investigate whether the programming of two hands was equivalent or they exploited different strategies. In the first experiment, participants were required to use one hand to grasp an object with visual feedback or to point to the center of one object without visual feedback on alternate trials, or to grasp an object without visual feedback and to point the center of one object with visual feedback on alternating trials. They then performed the tasks with the other hand. The result was that previous pointing task affected current grasping when it was performed by the left hand, but not the right hand. In experiment 2, we studied if the programming of the left (or right) hand would be affected by the pointing task performed on the previous trial not only by the same hand, but also by the right (or left) hand. Participants pointed and grasped the objects alternately with two hands. The result was similar with Experiment 1, i.e., left-hand grasping was affected by right-hand pointing, whereas right-hand grasping was immune from the interference from left hand. Taken together, the results suggest that when open- and closed-loop trials are interleaved, motor programming of grasping with the right hand was affected by the nature of the online feedback on the previous trial only if it was a grasping trial, suggesting that the trial-to-trial transfer depends on sensorimotor memory and not on task set. In contrast, motor programming of grasping with the left hand can use information about the nature of the online feedback on the previous trial to specify the parameters of the movement, even when the type of movement that occurred was quite different (i.e., pointing) and was performed with the right hand. This suggests that

  7. Evolutionary rescue and adaptation to abrupt environmental change depends upon the history of stress.

    PubMed

    Gonzalez, Andrew; Bell, Graham

    2013-01-19

    Whether evolution will be rapid enough to rescue declining populations will depend upon population size, the supply of genetic variation, the degree of maladaptation and the historical direction of selection. We examined whether the level of environmental stress experienced by a population prior to abrupt environmental change affects the probability of evolutionary rescue (ER). Hundreds of populations of two species of yeast, Saccharomyces cerevisiae and Saccharomyces paradoxus were exposed to a range of sublethal concentrations of salt for approximately a hundred generations before transfer to a concentration of salt lethal to the ancestor (150 g l(-1) NaCl). The fitness of surviving populations of both species was a quadratic function of yield: fitness was greatest for large populations that had been selected on low salt concentrations (less than 20 g l(-1) NaCl) and small populations that had adapted to high salt (more than 80 g l(-1) NaCl). However, differences occurred between species in the probability of ER. The frequency of ER was positively correlated with salt concentration for S. cerevisiae, but negatively correlated with salt concentration in S. paradoxus. These results not only demonstrate that past environmental conditions can determine the probability of ER after abrupt environmental change, but also suggest that there may even be differences between closely related species that are worth further exploration.

  8. The cost of antibiotic resistance depends on evolutionary history in Escherichia coli.

    PubMed

    Angst, Daniel C; Hall, Alex R

    2013-08-02

    The persistence of antibiotic resistance depends on the fitness effects of resistance elements in the absence of antibiotics. Recent work shows that the fitness effect of a given resistance mutation is influenced by other resistance mutations on the same genome. However, resistant bacteria acquire additional beneficial mutations during evolution in the absence of antibiotics that do not alter resistance directly but may modify the fitness effects of new resistance mutations. We experimentally evolved rifampicin-resistant and sensitive Escherichia coli in a drug-free environment, before measuring the effects of new resistance elements on fitness in antibiotic-free conditions. Streptomycin-resistance mutations had small fitness effects in rifampicin-resistant genotypes that had adapted to antibiotic-free growth medium, compared to the same genotypes without adaptation. We observed a similar effect when resistance was encoded by a different mechanism and carried on a plasmid. Antibiotic-sensitive bacteria that adapted to the same conditions showed the same pattern for some resistance elements but not others. Epistatic variation of costs of resistance can result from evolution in the absence of antibiotics, as well as the presence of other resistance mutations.

  9. Smoking history, nicotine dependence and opioid use in patients with chronic non-malignant pain.

    PubMed

    Plesner, K; Jensen, H I; Højsted, J

    2016-08-01

    Previous studies have demonstrated a positive association between smoking and addiction to opioids in patients with chronic non-malignant pain. This could be explained by a susceptibility in some patients to develop addiction. Another explanation could be that nicotine influences both pain and the opioid system. The objective of the study was to investigate whether smoking, former smoking ± nicotine use and nicotine dependence in patients with chronic non-malignant pain were associated with opioid use and addiction to opioids. The study was a cross-sectional study carried out at a multidisciplinary Danish pain centre. All patients aged 18 or more in treatment at the pain centre on the 1st of September 2013 were invited to participate in the study. A total of 98 patients (65%) participated in the study. The prevalence of current smokers was twice as high as in the general population. The prevalence of patients using opioids was 54% and the prevalence of addiction to opioids was 6%. No significant differences in addiction were found between the different smoking groups, but smokers and former smokers using nicotine tended to use opioids more frequently and at higher doses than never smokers and former smokers not using nicotine. The study supports previous evidence that smoking is associated with chronic pain. Our data suggest that information about use of nicotine substitution in chronic non-malignant patients are relevant both in a clinical setting, but also in future studies of the association between smoking habits, pain and opioid use. © 2016 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  10. Fundamental population-productivity relationships can be modified through density-dependent feedbacks of life-history evolution.

    PubMed

    Kuparinen, Anna; Stenseth, Nils Christian; Hutchings, Jeffrey A

    2014-12-01

    The evolution of life histories over contemporary time scales will almost certainly affect population demography. One important pathway for such eco-evolutionary interactions is the density-dependent regulation of population dynamics. Here, we investigate how fisheries-induced evolution (FIE) might alter density-dependent population-productivity relationships. To this end, we simulate the eco-evolutionary dynamics of an Atlantic cod (Gadus morhua) population under fishing, followed by a period of recovery in the absence of fishing. FIE is associated with increases in juvenile production, the ratio of juveniles to mature population biomass, and the ratio of the mature population biomass relative to the total population biomass. In contrast, net reproductive rate (R 0 ) and per capita population growth rate (r) decline concomitantly with evolution. Our findings suggest that FIE can substantially modify the fundamental population-productivity relationships that underlie density-dependent population regulation and that form the primary population-dynamical basis for fisheries stock-assessment projections. From a conservation and fisheries-rebuilding perspective, we find that FIE reduces R 0 and r, the two fundamental correlates of population recovery ability and inversely extinction probability.

  11. Social network drinking and family history contribute equally to first-onset alcohol dependence in high risk adults.

    PubMed

    McCutcheon, Vivia V; Lessov-Schlaggar, Christina N; Steinley, Douglas; Bucholz, Kathleen K

    2014-08-01

    Adult alcohol consumption is influenced by peer consumption, but whether peer drinking is associated with first-onset alcohol dependence (AD) in adults after age 30 is unknown. 703 adult participants in the St. Louis Epidemiologic Catchment Area Survey (ECA) with no prior history of AD, but with high risk based on previously reported drinking or family history, were re-interviewed 11 years after the last ECA assessment to detect new cases of AD (age at follow-up: M(S.D.)=42.9 (8.2)). Incident AD during the assessment interval was examined in relation to drinking patterns in the social network and history of alcohol problems in parents. Fifteen percent of the sample had a first-onset of AD; another 19.5% never developed AD but were high-risk drinkers at follow-up. Of those who developed AD, 32.1% were remitted and 67.9% were unremitted (current AD) or unstably remitted (asymptomatic high-risk drinkers). Compared to abstinent or low-risk drinkers who did not develop AD, high-risk drinkers with no AD and unremitted/unstably remitted individuals were 4 times as likely to report moderate drinkers in their networks and remitted individuals were nearly 3 times as likely to report network members in recovery from alcohol problems. Associations of social network drinking with remitted and current AD were similar in strength to those of parental alcohol problems. Social network drinking patterns are associated with high-risk drinking and with the development of incident AD in adults, with effects equal to that of alcohol problems in both parents. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Influence of procedural learning on Iowa Gambling Task performance among HIV+ individuals with history of substance dependence.

    PubMed

    Gonzalez, Raul; Wardle, Margaret; Jacobus, Joanna; Vassileva, Jasmin; Martin-Thormeyer, Eileen M

    2010-02-01

    HIV+ individuals have been shown to demonstrate deficits on the Iowa Gambling Task (IGT), a complex measure of "decision-making." Little remains known about what other neurocognitive processes may account for variability in IGT performance among HIV+ samples or the role of procedural learning (PL) in IGT performance. A sample of 49 HIV+ individuals with a history of substance use disorders was examined to explore the relationship between IGT performance and three measures of PL: The Rotary Pursuit, Mirror Star Tracing, and Weather Prediction tasks. We found no statistically significant relationships between IGT performance and any of the PL tasks, despite finding significant correlations among the PL tasks. This pattern of results persisted when analyzing IGT performance in various ways (e.g., performance on earlier trial blocks or impairment classifications). Although other nondeclarative processes (e.g., somatic markers) may be important for IGT performance, these findings do not support PL as an important component neurocognitive process for the IGT. Similarly, these results suggest that differences in PL performance does not account for the decision-making deficits or variability in performances observed on the IGT among HIV+ individuals with a history of substance dependence.

  13. Application of a time-dependent coalescence process for inferring the history of population size changes from DNA sequence data

    PubMed Central

    Polanski, Andrzej; Kimmel, Marek; Chakraborty, Ranajit

    1998-01-01

    Distribution of pairwise differences of nucleotides from data on a sample of DNA sequences from a given segment of the genome has been used in the past to draw inferences about the past history of population size changes. However, all earlier methods assume a given model of population size changes (such as sudden expansion), parameters of which (e.g., time and amplitude of expansion) are fitted to the observed distributions of nucleotide differences among pairwise comparisons of all DNA sequences in the sample. Our theory indicates that for any time-dependent population size, N(τ) (in which time τ is counted backward from present), a time-dependent coalescence process yields the distribution, p(τ), of the time of coalescence between two DNA sequences randomly drawn from the population. Prediction of p(τ) and N(τ) requires the use of a reverse Laplace transform known to be unstable. Nevertheless, simulated data obtained from three models of monotone population change (stepwise, exponential, and logistic) indicate that the pattern of a past population size change leaves its signature on the pattern of DNA polymorphism. Application of the theory to the published mtDNA sequences indicates that the current mtDNA sequence variation is not inconsistent with a logistic growth of the human population. PMID:9576903

  14. Predictors of transition to heroin use among initially non-opioid dependent illicit pharmaceutical opioid users: A natural history study.

    PubMed

    Carlson, Robert G; Nahhas, Ramzi W; Martins, Silvia S; Daniulaityte, Raminta

    2016-03-01

    Increases in illicit pharmaceutical opioid (PO) use have been associated with risk for transition to heroin use. We identify predictors of transition to heroin use among young, illicit PO users with no history of opioid dependence or heroin use at baseline. Respondent-driven sampling recruited 383 participants; 362 returned for at least one biannual structured interview over 36 months. Cox regression was used to test for associations between lagged predictors and hazard of transition to heroin use. Potential predictors were based on those suggested in the literature. We also computed population attributable risk (PAR) and the rate of heroin transition. Over 36 months, 27 (7.5%) participants initiated heroin use; all were white, and the rate of heroin initiation was 2.8% per year (95% CI=1.9%-4.1%). Mean length of PO at first reported heroin use was 6.2 years (SD=1.9). Lifetime PO dependence (AHR=2.39, 95% CI=1.07-5.48; PAR=32%, 95% CI=-2% to 64%), early age of PO initiation (AHR=3.08, 95%; CI=1.26-7.47; PAR=30%, 95% CI=2%-59%), using illicit POs to get high but not to self-medicate a health problem (AHR=4.83, 95% CI=2.11-11.0; PAR=38%, 95% CI=12%-65%), and ever using PO non-orally most often (AHR=6.57, 95% CI=2.81-17.2; PAR=63%, 95% CI=31%-86%) were significant predictors. This is one of the first prospective studies to test observations from previous cross-sectional and retrospective research on the relationship between illicit PO use and heroin initiation among young, initially non-opioid dependent PO users. The results provide insights into targets for the design of urgently needed prevention interventions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Predictors of transition to heroin use among initially non-opioid dependent illicit pharmaceutical opioid users: A natural history study

    PubMed Central

    Carlson, Robert G.; Nahhas, Ramzi W.; Martins, Silvia S.; Daniulaityte, Raminta

    2016-01-01

    Background Increases in illicit pharmaceutical opioid (PO) use have been associated with risk for transition to heroin use. We identify predictors of transition to heroin use among young, illicit PO users with no history of opioid dependence or heroin use at baseline. Methods Respondent-driven sampling recruited 383 participants; 362 returned for at least one biannual structured interview over 36 months. Cox regression was used to test for associations between lagged predictors and hazard of transition to heroin use. Potential predictors were based on those suggested in the literature. We also computed population attributable risk (PAR) and the rate of heroin transition. Results Over 36 months, 27 (7.5%) participants initiated heroin use; all were white, and the rate of heroin initiation was 2.8% per year (95% CI=1.9%–4.1%). Mean length of PO at first reported heroin use was 6.2 years (SD=1.9). Lifetime PO dependence (AHR=2.39, 95% CI= 1.07–5.48; PAR=32%, 95% CI=−2%–64%), early age of PO initiation (AHR=3.08, 95%; CI= 1.26–7.47; PAR=30%, 95% CI=2%–59%), using illicit POs to get high but not to self-medicate a health problem (AHR=4.83, 95% CI= 2.11–11.0; PAR=38%, 95% CI=12%–65%), and ever using PO non-orally most often (AHR=6.57, 95% CI=2.81–17.2; PAR=63%, 95% CI=31%–86%) were significant predictors. Conclusion This is one of the first prospective studies to test observations from previous cross-sectional and retrospective research on the relationship between illicit PO use and heroin initiation among young, initially non-opioid dependent PO users. The results provide insights into targets for the design of urgently needed prevention interventions. PMID:26785634

  16. Decreased Sensitivity to Long-Distance Dependencies in Children with a History of Specific Language Impairment: Electrophysiological Evidence

    PubMed Central

    Purdy, J. D.; Leonard, Laurence B.; Weber-Fox, Christine; Kaganovich, Natalya

    2015-01-01

    Purpose One possible source of tense and agreement limitations in children with SLI is a weakness in appreciating structural dependencies that occur in many sentences in the input. We tested this possibility in the present study. Method Children with a history of SLI (H-SLI; N = 12; M age 9;7) and typically developing same-age peers (TD; N = 12; M age 9;7) listened to and made grammaticality judgments about grammatical and ungrammatical sentences involving either a local agreement error (e.g., Every night they talks on the phone) or a long-distance finiteness error (e.g., He makes the quiet boy talks a little louder). Electrophysiological (ERP) and behavioral (accuracy) measures were obtained. Results Local agreement errors elicited the expected anterior negativity and P600 components in both groups of children. However, relative to the TD group, the P600 effect for the long-distance finiteness errors was delayed, reduced in amplitude, and shorter in duration for the H-SLI group. The children's grammaticality judgments were consistent with the ERP findings. Conclusions Children with H-SLI seem to be relatively insensitive to the finiteness constraints that matrix verbs place on subject-verb clauses that appear later in the sentence. PMID:24686983

  17. Theoretical life history responses of juvenile Oncorhynchus mykiss to changes in food availability using a dynamic state-dependent approach

    USGS Publications Warehouse

    Romine, Jason G.; Benjamin, Joseph R.; Perry, Russell W.; Casal, Lynne; Connolly, Patrick J.; Sauter, Sally S.

    2013-01-01

    Marine subsidies can play an important role in the growth, survival, and migratory behavior of rearing juvenile salmonids. Availability of high-energy, marine-derived food sources during critical decision windows may influence the timing of emigration or the decision to forego emigration completely and remain in the freshwater environment. Increasing growth and growth rate during these decision windows may result in an altered juvenile population structure, which will ultimately affect the adult population age-structure. We used a state dependent model to understand how the juvenile Oncorhynchus mykiss population structure may respond to increased availability of salmon eggs in their diet during critical decision windows. Our models predicted an increase in smolt production until coho salmon eggs comprised more than 50 percent of juvenile O. mykiss diet at the peak of the spawning run. At higher-than intermediate levels of egg consumption, smolt production decreased owing to increasing numbers of fish adopting a resident life-history strategy. Additionally, greater growth rates decreased the number of age-3 smolts and increased the number of age-2 smolts. Increased growth rates with higher egg consumption also decreased the age at which fish adopted the resident pathway. Our models suggest that the introduction of a high-energy food source during critical periods of the year could be sufficient to increase smolt production.

  18. Spatially-resolved mapping of history-dependent coupled electrochemical and electronical behaviors of electroresistive NiO

    DOE PAGES

    Sugiyama, Issei; Kim, Yunseok; Jesse, Stephen; ...

    2014-10-22

    Bias-induced oxygen ion dynamics underpins a broad spectrum of electroresistive and memristive phenomena in oxide materials. Although widely studied by device-level and local voltage-current spectroscopies, the relationship between electroresistive phenomena, local electrochemical behaviors, and microstructures remains elusive. Here, the interplay between history-dependent electronic transport and electrochemical phenomena in a NiO single crystalline thin film with a number of well-defined defect types is explored on the nanometer scale using an atomic force microscopy-based technique. A variety of electrochemically-active regions were observed and spatially resolved relationship between the electronic and electrochemical phenomena was revealed. The regions with pronounced electroresistive activity were furthermore » correlated with defects identified by scanning transmission electron microscopy. Using fully coupled mechanical-electrochemical modeling, we illustrate that the spatial distribution of strain plays an important role in electrochemical and electroresistive phenomena. In conclusion, these studies illustrate an approach for simultaneous mapping of the electronic and ionic transport on a single defective structure level such as dislocations or interfaces, and pave the way for creating libraries of defect-specific electrochemical responses.« less

  19. History dependence of the electromyogram: Implications for isometric steady-state EMG parameters following a lengthening or shortening contraction.

    PubMed

    Jones, Alexis A; Power, Geoffrey A; Herzog, Walter

    2016-04-01

    Residual force enhancement (RFE) and force depression (FD) refer to an increased or decreased force following an active lengthening or shortening contraction, respectively, relative to the isometric force produced at the same activation level and muscle length. Our intent was to determine if EMG characteristics differed in the RFE or FD states compared with a purely isometric reference contraction for maximal and submaximal voluntary activation of the adductor pollicis muscle. Quantifying these alterations to EMG in history-dependent states allows for more accurate modeling approaches for movement control in the future. For maximal voluntary contractions (MVC), RFE was 6-15% (P<0.001) and FD was 12-19% (P<0.001). The median frequency of the EMG was not different between RFE, FD and isometric reference contractions for the 100% and 40% MVC intensities (P>0.05). However, root mean square EMG (EMGRMS) amplitude for the submaximal contractions was higher in the FD and lower in the RFE state, respectively (P<0.05). For maximal contractions, EMGRMS was lower for the FD state but was the same for the RFE state compared to the isometric reference contractions (P>0.05). Neuromuscular efficiency (NME; force/EMG) was lower in the force depressed state and higher in the force enhanced state (P<0.05) compared to the isometric reference contractions. EMG spectral properties were not altered between the force-enhanced and depressed states relative to the isometric reference contractions, while EMG amplitude measures were.

  20. Spatially-resolved mapping of history-dependent coupled electrochemical and electronical behaviors of electroresistive NiO

    SciTech Connect

    Sugiyama, Issei; Kim, Yunseok; Jesse, Stephen; Strelcov, Evgheni; Kumar, Amit; Tselev, Alexander; Rahani, Ehasan Kabiri; Shenoy, Vivek B.; Yamamoto, Takahisa; Shibata, Naoya; Ikuhara, Yuichi; Kalinin, Sergei V.

    2014-10-22

    Bias-induced oxygen ion dynamics underpins a broad spectrum of electroresistive and memristive phenomena in oxide materials. Although widely studied by device-level and local voltage-current spectroscopies, the relationship between electroresistive phenomena, local electrochemical behaviors, and microstructures remains elusive. Here, the interplay between history-dependent electronic transport and electrochemical phenomena in a NiO single crystalline thin film with a number of well-defined defect types is explored on the nanometer scale using an atomic force microscopy-based technique. A variety of electrochemically-active regions were observed and spatially resolved relationship between the electronic and electrochemical phenomena was revealed. The regions with pronounced electroresistive activity were further correlated with defects identified by scanning transmission electron microscopy. Using fully coupled mechanical-electrochemical modeling, we illustrate that the spatial distribution of strain plays an important role in electrochemical and electroresistive phenomena. In conclusion, these studies illustrate an approach for simultaneous mapping of the electronic and ionic transport on a single defective structure level such as dislocations or interfaces, and pave the way for creating libraries of defect-specific electrochemical responses.

  1. Decreased sensitivity to long-distance dependencies in children with a history of specific language impairment: electrophysiological evidence.

    PubMed

    Purdy, J D; Leonard, Laurence B; Weber-Fox, Christine; Kaganovich, Natalya

    2014-06-01

    One possible source of tense and agreement limitations in children with specific language impairment (SLI) is a weakness in appreciating structural dependencies that occur in many sentences in the input. This possibility was tested in the present study. Children with a history of SLI (H-SLI; n = 12; M = 9;7 [years;months]) and typically developing same-age peers (TD; n = 12; M = 9;7) listened to and made grammaticality judgments about grammatical and ungrammatical sentences involving either a local agreement error (e.g., "Every night they talks on the phone") or a long-distance finiteness error (e.g., "He makes the quiet boy talks a little louder"). Electrophysiological (ERP) and behavioral (accuracy) measures were obtained. Local agreement errors elicited the expected anterior negativity and P600 components in both groups of children. However, relative to the TD group, the P600 effect for the long-distance finiteness errors was delayed, reduced in amplitude, and shorter in duration for the H-SLI group. The children's grammaticality judgments were consistent with the ERP findings. Children with H-SLI seem to be relatively insensitive to the finiteness constraints that matrix verbs place on subject-verb clauses that appear later in the sentence.

  2. Deficits in complex motor functions, despite no evidence of procedural learning deficits, among HIV+ individuals with history of substance dependence.

    PubMed

    Gonzalez, Raul; Jacobus, Joanna; Amatya, Anup K; Quartana, Phillip J; Vassileva, Jasmin; Martin, Eileen M

    2008-11-01

    Human immunodeficiency virus (HIV) and drugs of abuse affect common neural systems underlying procedural memory, including the striatum. The authors compared performance of 48 HIV seropositive (HIV+) and 48 HIV seronegative (HIV-) participants with history of cocaine and/or heroin dependence across multiple Trial Blocks of three procedural learning (PL) tasks: Rotary Pursuit (RP), Mirror Star Tracing (MST), and Weather Prediction (WP). Groups were well matched on demographic, psychiatric, and substance use parameters, and all participants were verified abstinent from drugs. Mixed model analyses of variance revealed that the individuals in the HIV+ group performed more poorly across all tasks, with a significant main effect of HIV serostatus observed on the Mirror Star Tracing and a trend toward significance obtained for the Rotary Pursuit task. No significant differences were observed on the Weather Prediction task. Both groups demonstrated significant improvements in performance across all three procedural learning tasks. It is important to note that no significant Serostatus x Trial Block interactions were observed on any task. Thus, the individuals in the HIV+ group tended to perform worse than those in the HIV- group across all trial blocks of procedural learning tasks with motor demands, but showed no differences in their rate of improvement across all tasks. These findings are consistent with HIV--associated deficits in complex motor skills, but not in procedural learning.

  3. The effect of the nonlinear velocity and history dependencies of the aerodynamic force on the dynamic response of a rotating wind turbine blade

    NASA Astrophysics Data System (ADS)

    van der Male, Pim; van Dalen, Karel N.; Metrikine, Andrei V.

    2016-11-01

    Existing models for the analysis of offshore wind turbines account for the aerodynamic action on the turbine rotor in detail, requiring a high computational price. When considering the foundation of an offshore wind turbine, however, a reduced rotor model may be sufficient. To define such a model, the significance of the nonlinear velocity and history dependency of the aerodynamic force on a rotating blade should be known. Aerodynamic interaction renders the dynamics of a rotating blade in an ambient wind field nonlinear in terms of the dependency on the wind velocity relative to the structural motion. Moreover, the development in time of the aerodynamic force does not follow the flow velocity instantaneously, implying a history dependency. In addition, both the non-uniform blade geometry and the aerodynamic interaction couple the blade motions in and out of the rotational plane. Therefore, this study presents the Euler-Bernoulli formulation of a twisted rotating blade connected to a rigid hub, excited by either instantaneous or history-dependent aerodynamic forces. On this basis, the importance of the history dependency is determined. Moreover, to assess the nonlinear contributions, both models are linearized. The structural response is computed for a stand-still and a rotating blade, based on the NREL 5-MW turbine. To this end, the model is reduced on the basis of its first three free-vibration mode shapes. Blade tip response predictions, computed from turbulent excitation, correctly account for both modal and directional couplings, and the added damping resulting from the dependency of the aerodynamic force on the structural motion. Considering the deflection of the blade tip, the history-dependent and the instantaneous force models perform equally well, providing a basis for the potential use of the instantaneous model for the rotor reduction. The linearized instantaneous model provides similar results for the rotating blade, indicating its potential

  4. Inverse characterization method for mechanical properties of strain/strain-rate/temperature/temperature-history dependent steel sheets and its application for hot press forming

    NASA Astrophysics Data System (ADS)

    Kim, Hyunki; Kim, Dongun; Ahn, Kanghwan; Yoo, Donghoon; Son, Hyun-Sung; Kim, Gyo-Sung; Chung, Kwansoo

    2015-09-01

    In order to measure the flow curves of steel sheets at high temperatures, which are dependent on strain and strain rate as well as temperature and temperature history, a tensile test machine and specimens were newly developed in this work. Besides, an indirect method to characterize mechanical properties at high temperatures was developed by combining experiments and its numerical analysis, in which temperature history were also accounted for. Ultimately, a modified Johnson-Cook type hardening law, accounting for the dependence of hardening behavior with deterioration on strain rate as well as temperature, was successfully developed covering both pre- and post-ultimate tensile strength ranges for a hot press forming steel sheet. The calibrated hardening law obtained based on the inverse characterization method was then applied and validated for hot press forming of a 2-D mini-bumper as for distributions of temperature history, thickness and hardness considering the continuous cooling transformation diagram. The results showed reasonably good agreement with experiments

  5. Life history traits influence the strength of distance- and density-dependence at different life stages of two Amazonian palms.

    PubMed

    Choo, Juanita; Carasco, Cecilia; Alvarez-Loayza, Patricia; Simpson, Beryl B; Economo, Evan P

    2017-07-01

    Natural enemies are known to be important in regulating plant populations and contributing to species coexistence (Janzen-Connell effects). The strength of Janzen-Connell effects (both distance- and density-effects) varies across species, but the life history traits that may mediate such a variation are not well understood. This study examined Janzen-Connell effects across the life stages (seed through adult stages) of two sympatric palm species with distinct phenologies and shade tolerances, two traits that may mediate the strength and timing of Janzen-Connell effects. Populations of two common palm species, Attalea phalerata and Astrocaryum murumuru , were studied in Manu National Park, Peru. Seed predation experiments were conducted to assess Janzen-Connell effects at the seed stage. In the post-seed stages, spatial point pattern analyses of the distributions of individuals and biomass were used to infer the strength of distance- and density-effects. Seed predation was both negative distance- and density-dependent consistent with the Janzen-Connell effects. However, only seedling recruitment for asynchronously fruiting Attalea phalerata was depressed near adults while recruitment remained high for synchronously fruiting Astrocaryum murumuru , consistent with weak distance-effects. Negative density-effects were strong in the early stages for shade-intolerant Attalea phalerata but weak or absent in shade-tolerant Astrocaryum murumuru. Distance- and density-effects varied among the life stages of the two palm species in a manner that corresponded to their contrasting phenology and shade tolerance. Generalizing such connections across many species would provide a route to understanding how trait-mediated Janzen-Connell effects scale up to whole communities of species.

  6. Dependence of low energy ion beam exposure effects in silicon on ion species, exposure history, and material properties

    NASA Astrophysics Data System (ADS)

    Davis, R. J.; Climent, A.; Fonash, S. J.

    1985-03-01

    Several groups have shown that low energy (25-1500 eV) ion bombardment of silicon causes significant surface damage; these disordered layers are hundreds of ángströms deep and are easily characterized by electron spin resonance and Rutherford backscattering techniques. This surface damage also manifests itself as positive charge residing at the metal-semiconductor interface of metal contacts to these layers. Recently we have shown that this damage increases with the inverse of the ion size, if ion energy is kept constant. However, we have demonstrated that impingement by the lightest of ions (H +) can electrically passivate the damage caused by other ions; namely, hydrogen itself causes extensive damage, but it also passivates by tying up dangling bonds. This interaction of hydrogen with the damage caused by other ions is fairly complex. For example, the 0.4 keV hydrogen ions used to completely passivate 1.0 keV Ar + ion damage (as determined by electrical measurements) cause significant disorder and result in electrically active damage, when not preceded by the Ar + impingement. Thus low energy ion beam damage is found to depend on ion size, ion chemical activity, and sample exposure history. In addition, we have also seen significant differences in the annealing behavior of ion damage in float-zoned versus Czochralski-grown silicon. While 1.0 keV Ar + damage of CZ silicon anneals only at 1000°C, damaged FZ silicon anneals nearly completely at 800°C. Such behavior strongly suggests that background oxygen and carbon may play a role in ion beam damage of silicon.

  7. Distinct intrinsic functional brain network abnormalities in methamphetamine-dependent patients with and without a history of psychosis.

    PubMed

    Ipser, Jonathan C; Uhlmann, Anne; Taylor, Paul; Harvey, Brian H; Wilson, Don; Stein, Dan J

    2016-12-05

    Chronic methamphetamine use is associated with executive functioning deficits that suggest dysfunctional cognitive control networks (CCNs) in the brain. Likewise, abnormal connectivity between intrinsic CCNs and default mode networks (DMNs) has also been associated with poor cognitive function in clinical populations. Accordingly, we tested the extent to which methamphetamine use predicts abnormal connectivity between these networks, and whether, as predicted, these abnormalities are compounded in patients with a history of methamphetamine-associated psychosis (MAP). Resting-state fMRI data were acquired from 46 methamphetamine-dependent patients [19 with MAP, 27 without (MD)], as well as 26 healthy controls (CTRL). Multivariate network modelling and whole-brain voxel-wise connectivity analyses were conducted to identify group differences in intrinsic connectivity across four cognitive control and three DMN networks identified using an independent components analysis approach (meta-ICA). The relationship of network connectivity and psychotic symptom severity, as well as antipsychotic treatment and methamphetamine use variables, was also investigated. Robust evidence of hyper-connectivity was observed between the right frontoparietal and anterior DMN networks in MAP patients, and 'normalized' with increased duration of treatment with antipsychotics. Attenuation of anticorrelated anterior DMN-dorsal attention network activity was also restricted to this group. Elevated coupling detected in MD participants between anterior and posterior DMN networks became less apparent with increasing duration of abstinence from methamphetamine. In summary, we observed both alterations of RSN connectivity between DMN networks with chronic methamphetamine exposure, as well as DMN-CCN coupling abnormalities consistent with possible MAP-specific frontoparietal deficits in the biasing of task-appropriate network activity. © 2016 Society for the Study of Addiction.

  8. The Time Dependance of Dynamic Topography: Mantle Dynamic Contributions to Local and Global Sea-Level Histories

    NASA Astrophysics Data System (ADS)

    Durbin, C. J.; Shahnas, M.; Peltier, W. R.

    2012-12-01

    model to be employed to study the present state of the mantle and its evolution in the recent geological past. The predictions of the model that interest us are those of the rate of uplift and depression of the crust that contribute to records of relative sea level history over timescales sufficiently long to encompass several Late Quaternary glacial cycles. We employ a number of available local records of the time dependence of dynamical topography such as the coral based Barbados record of Peltier and Fairbanks (2006, QSR 25, pp. 3322-3337) to first demonstrate the accuracy with which the convection model is able to reconcile such observational constraints. Although several of the best available constraint data sets derive from regions in the near vicinity of active subduction zones, we proceed to apply the model's predictions to a number of (assumed to be) passive continental margins from which data have been derived that have been assumed to represent variations in eustatic sea level due to the variation of continental land ice volume such as those recently discussed by Miller et al. (2012, Geology 20, pp. 407-410). We assess the extent to which the passive continental margin assumption may have led to significant errors in the inference of global sea level rise for the mid-Pliocene interval of time centered upon 3 Ma.

  9. Prazosin + naltrexone decreases alcohol drinking more effectively than does either drug alone in P rats with a protracted history of extensive voluntary alcohol drinking, dependence and multiple withdrawals

    PubMed Central

    Rasmussen, Dennis D; Kincaid, Carrie L; Froehlich, Janice C

    2015-01-01

    Background Prazosin (PRZ, an α1-adrenergic receptor antagonist) and naltrexone (NTX, a non-specific opioid receptor antagonist) each decrease alcohol drinking when administered to rats selectively-bred for high voluntary alcohol drinking (alcohol-preferring, or “P”), and the combination of PRZ+NTX decreases alcohol drinking more effectively than does either drug alone. Since drug responsiveness can depend on history of alcohol drinking and dependence, we investigated whether various schedules of PRZ and NTX administration, alone or in combination, are effective in decreasing alcohol drinking in male P rats with a history of protracted voluntary alcohol drinking, dependence and repeated withdrawals closely resembling human alcoholism. Methods Male P rats became alcohol-dependent during 1 year of ad libitum 24 h/day access to food, water and 20% alcohol with repetitive temporary alcohol withdrawals. Four sequential studies then addressed effects of oral PRZ (2 mg/kg) and NTX (10 mg/kg), alone or together, on alcohol drinking during: 1) daily alcohol access with daily drug treatment, 2) intermittent alcohol access with daily drug treatment, 3) intermittent alcohol access with occasional drug treatment, and 4) post-deprivation reinstatement of alcohol access. Results The combination of PRZ+NTX consistently suppressed alcohol drinking during daily or intermittent alcohol access conditions and when drug treatment was either daily or occasional. PRZ+NTX was consistently more effective than either drug alone. The reduction in alcohol drinking was not due to sedation, motor effects or malaise. Conclusions Both daily and “as-needed” treatment with PRZ+NTX are highly effective in suppressing daily, intermittent and post-deprivation alcohol drinking in male P rats with a protracted history of alcohol dependence and repeated withdrawals. This drug combination may be especially effective for treating individuals with long histories of heavy alcohol abuse, dependence and

  10. The activity of serum beta-galactosidase in colon cancer patients with a history of alcohol and nicotine dependence: preliminary data.

    PubMed

    Waszkiewicz, Napoleon; Szajda, Sławomir Dariusz; Waszkiewicz, Magdalena; Wojtulewska-Supron, Aleksandra; Szulc, Agata; Kępka, Alina; Chojnowska, Sylwia; Dadan, Jacek; Ładny, Jerzy Robert; Zwierz, Krzysztof; Zalewska-Szajda, Beata

    2013-08-26

    Beta-galactosidase (GAL) is a lysosomal exoglycosidase involved in the catabolism of glycoconjugates through the sequential release of beta-linked terminal galactosyl residues. The stimulation of activity of exoglycosidases and other degradative enzymes has been noted in cancers as well as in alcohol and nicotine addiction separately. This is the first study to evaluate the activity of the serum senescence marker GAL in colon cancer patients with a history of alcohol and nicotine dependence, as a potential factor of worse cancer prognosis. The material was serum of 18 colon cancer patients and 10 healthy volunteers. Ten colon cancer patients met alcohol and nicotine dependence criteria. The activity of beta-galactosidase (pkat/ml) was determined by the colorimetric method. Comparisons between groups were made using the Kruskal-Wallis analysis and differences evaluated using the Mann-Whitney U test. Spearman's rank correlation coefficient was used to measure the statistical dependence between two variables. The activity of serum GAL was significantly higher in colon cancer patients with a history of alcohol and nicotine dependence, in comparison to colon cancer patients without a history of drinking/smoking (p=0.015; 46% increase), and the controls (p=0.0002; 81% increase). The activity of serum GAL in colon cancer patients without a history of alcohol/nicotine dependence was higher than the activity in the controls (p = 0.043; 24% increase). Higher activity of beta-galactosidase may potentially reflect the accelerated growth of the cancer, invasion, metastases, and maturation, when alcohol and nicotine dependence coincide with colon cancer. For a better prognosis of colon cancer, alcohol and nicotine withdrawal seems to be required.

  11. Prazosin + Naltrexone Decreases Alcohol Drinking More Effectively Than Does Either Drug Alone in P Rats with a Protracted History of Extensive Voluntary Alcohol Drinking, Dependence, and Multiple Withdrawals.

    PubMed

    Rasmussen, Dennis D; Kincaid, Carrie L; Froehlich, Janice C

    2015-09-01

    Prazosin (PRZ; an α1 -adrenergic receptor antagonist) and naltrexone (NTX; a nonspecific opioid receptor antagonist) each decrease alcohol drinking when administered to rats selectively bred for high voluntary alcohol drinking (alcohol-preferring or "P"), and the combination of PRZ + NTX decreases alcohol drinking more effectively than does either drug alone. As drug responsiveness can depend on history of alcohol drinking and dependence, we investigated whether various schedules of PRZ and NTX administration, alone or in combination, are effective in decreasing alcohol drinking in male P rats with a history of protracted voluntary alcohol drinking, dependence, and repeated withdrawals closely resembling human alcoholism. Male P rats became alcohol-dependent during 1 year of ad libitum 24 h/d access to food, water, and 20% alcohol with repetitive temporary alcohol withdrawals. Four sequential studies then addressed effects of oral PRZ (2 mg/kg) and NTX (10 mg/kg), alone or together, on alcohol drinking during: (i) daily alcohol access with daily drug treatment, (ii) intermittent alcohol access with daily drug treatment, (iii) intermittent alcohol access with occasional drug treatment, and (iv) postdeprivation reinstatement of alcohol access. The combination of PRZ + NTX consistently suppressed alcohol drinking during daily or intermittent alcohol access conditions and when drug treatment was either daily or occasional. PRZ + NTX was consistently more effective than either drug alone. The reduction in alcohol drinking was not due to sedation, motor effects, or malaise. Both daily and "as-needed" treatment with PRZ + NTX are highly effective in suppressing daily, intermittent, and postdeprivation alcohol drinking in male P rats with a protracted history of alcohol dependence and repeated withdrawals. This drug combination may be especially effective for treating individuals with long histories of heavy alcohol abuse, dependence, and repeated relapse, as commonly

  12. Effect of spinal manipulation on the development of history-dependent responsiveness of lumbar paraspinal muscle spindles in the cat

    PubMed Central

    Cao, Dong-Yuan; Pickar, Joel G.

    2014-01-01

    We determined whether spinal manipulation could prevent and/or reverse the decrease and increase in paraspinal muscle spindle responsiveness caused respectively by lengthening and shortening histories of the lumbar muscles. Single unit spindle activity from multifidus and longissimus muscles was recorded in the L6 dorsal root in anesthetized cats. Muscle history was created and spinal manipulation delivered (thrust amplitude: 1.0mm, duration: 100ms) using a feedback-controlled motor attached to the L6 spinous process. Muscle spindle discharge to a fixed vertebral position (static test) and to vertebral movement (dynamic test) was evaluated following the lengthening and shortening histories. For the static test, changes in muscle spindle responsiveness were significantly less when spinal manipulation followed muscle history (p<0.01), but not when spinal manipulation preceded it (p>0.05). For the dynamic test, spinal manipulation did not significantly affect the history-induced change in muscle spindle responsiveness. Spinal manipulation may partially reverse the effects of muscle history on muscle spindle signaling of vertebral position. PMID:24932019

  13. Effect of spinal manipulation on the development of history-dependent responsiveness of lumbar paraspinal muscle spindles in the cat.

    PubMed

    Cao, Dong-Yuan; Pickar, Joel G

    2014-06-01

    We determined whether spinal manipulation could prevent and/or reverse the decrease and increase in paraspinal muscle spindle responsiveness caused respectively by lengthening and shortening histories of the lumbar muscles. Single unit spindle activity from multifidus and longissimus muscles was recorded in the L6 dorsal root in anesthetized cats. Muscle history was created and spinal manipulation delivered (thrust amplitude: 1.0mm, duration: 100ms) using a feedback-controlled motor attached to the L6 spinous process. Muscle spindle discharge to a fixed vertebral position (static test) and to vertebral movement (dynamic test) was evaluated following the lengthening and shortening histories. For the static test, changes in muscle spindle responsiveness were significantly less when spinal manipulation followed muscle history (p<0.01), but not when spinal manipulation preceded it (p>0.05). For the dynamic test, spinal manipulation did not significantly affect the history-induced change in muscle spindle responsiveness. Spinal manipulation may partially reverse the effects of muscle history on muscle spindle signaling of vertebral position.

  14. The Investigation of Tramadol Dependence with No History of Substance Abuse: A Cross-Sectional Survey of Spontaneously Reported Cases in Guangzhou City, China

    PubMed Central

    Zhang, Haoran; Liu, Zhimin

    2013-01-01

    The study was to survey and assess the drug dependence and abuse potential of tramadol with no history of substance abuse. Subjects of tramadol dependence with no prior history of substance abuse were surveyed by interview. Physical dependence of tramadol was assessed using 10 items opiate withdrawal scale (OWS), and psychological dependence was assessed by Addiction Research Center Inventory—Chinese Version (ARCI-CV). Twenty-three male subjects (the median age was 23.4 ± 4.1 years) referred to the addiction unit in Medical Hospital of Guangzhou with tramadol abuse problems were included in this cross-sectional study. The control group included 87 heroin addicts, 60 methamphetamine (MA) abusers, and 50 healthy men. The scores of OWS of tramadol were 0.83–2.30; the mean scores of identifying euphoric effects–MBG, sedative effects–PCAG, and psychotomimetic effects–LSD of ARCI were 8.96 ± 3.08, 6.52 ± 3.25, and 6.65 ± 2.50, respectively, F = 4.927, P < 0.001. Scores of MBG scale in tramadol did not differ from those in heroin and MA groups (P > 0.05) but were higher than those in healthy men (P < 0.05). Tramadol with no history of substance abuse has a clear risk of producing high abuse potential under the long-term infrequent abuse and the high doses. PMID:24151592

  15. Solution of the equation of heat conduction with time dependent sources: Programmed application to planetary thermal history

    NASA Technical Reports Server (NTRS)

    Conel, J. E.

    1975-01-01

    A computer program (Program SPHERE) solving the inhomogeneous equation of heat conduction with radiation boundary condition on a thermally homogeneous sphere is described. The source terms are taken to be exponential functions of the time. Thermal properties are independent of temperature. The solutions are appropriate to studying certain classes of planetary thermal history. Special application to the moon is discussed.

  16. Associations between age of onset and lifetime history of panic attacks and alcohol use, abuse, and dependence in a representative sample.

    PubMed

    Bernstein, Amit; Zvolensky, Michael J; Sachs-Ericsson, Natalie; Schmidt, Norman B; Bonn-Miller, Marcel O

    2006-01-01

    The present investigation evaluated associations between lifetime panic attacks and lifetime alcohol use, abuse, and dependence. Specifically, the relations between lifetime panic attacks and alcohol use, abuse, and dependence were examined after controlling for theoretically relevant variables of comorbid psychopathology and polysubstance use. Data for this study were obtained from a large statewide survey, the Colorado Social Health Survey. Participants were contacted using randomly sampled household addresses (response rate was 72%) and interviews took place in participants' homes. The study consisted of a representative sample of the Colorado general adult population (n = 4,745; 52% women). The Diagnostic Interview Schedule (American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders [3rd ed]. Washington [DC]: Author. 1980) was administered to obtain Axis I diagnoses. After controlling for theoretically relevant variables of comorbid psychopathology and polysubstance use, a lifetime history of panic attacks was significantly associated with alcohol dependence but not alcohol use or abuse. In addition, among participants reporting a lifetime history of both panic attacks and alcohol abuse or dependence, the number of participants for whom panic attacks developmentally preceded the onset of alcohol use problems was significantly greater (85.5%) than the number of participants for whom alcohol use problems preceded the onset of panic attacks (13.4%) or the number of participants for whom these problems developed at the same age (2.2%). These data suggest panic attacks, particularly of early onset, may serve as a risk marker for alcohol dependence.

  17. Impacts of Repeated Glyphosate Use on Wheat-Associated Bacteria are Small and Depend on Glyphosate-Use History.

    PubMed

    Schlatter, Daniel C; Yin, Chuntao; Hulbert, Scot; Burke, Ian; Paulitz, Timothy

    2017-09-01

    Glyphosate is the most widely used herbicide worldwide and a critical tool for weed control in no-till cropping systems. However, there are concerns about non-target impacts of long-term glyphosate use on soil microbial communities. We investigated the impacts of repeated glyphosate treatments on bacterial communities in the soil and rhizosphere of wheat in soils with and without long-term history of glyphosate use. We cycled wheat in the greenhouse using soils from 4 paired fields under no-till (20+ years history of glyphosate) or no history of use. At each cycle, we terminated plants with glyphosate (2x field rate) or by removing the crowns and characterized soil and rhizosphere bacterial communities. Location, cropping history, year, and proximity to the roots had much stronger effects on bacterial communities than did glyphosate, which only explained 2-5% of the variation. Less than 1% of all taxa were impacted by glyphosate, more in soils with a long history of use, and more increased than decreased in relative abundance. Glyphosate had minimal impacts on soil and rhizosphere bacteria of wheat, although dying roots after glyphosate application may provide a 'greenbridge' favoring some copiotrophic taxa.IMPORTANCE Glyphosate (Roundup) is the most widely used herbicide in the world, and the foundation of Roundup Ready soybeans, corn, and the no-till cropping system. But there have been recent concerns about non-target impacts of glyphosate on soil microbes. Using next-generation sequencing methods and glyphosate treatments of wheat plants, we described the bacterial communities in the soil and rhizosphere of wheat grown in Pacific Northwest soils from across multiple years, different locations, and soils with different histories of glyphosate use. The effects of glyphosate were subtle, and much less than drivers such as location and cropping systems. Only a small percentage of the bacterial groups were influenced by glyphosate, and most of those were stimulated

  18. Field and sample history dependence of the compensation temperature in Sm 0.97Gd 0.03Al 2

    NASA Astrophysics Data System (ADS)

    Vaidya, U. V.; Rakhecha, V. C.; Sumithra, S.; Ramakrishnan, S.; Grover, A. K.

    2007-03-01

    We present magnetization data on three polycrystalline specimens of Sm 0.97Gd 0.03Al 2: (1) as-cast (grainy texture), (2) powder, and (3) re-melted fast-quenched (plate). The data are presented for nominally zero- (ZFC) and high-field-cooling (HFC) histories. A zero cross-over in magnetization curve at some temperature T= T0 was seen in ZFC data on grainy and powder samples, but not in the plate sample. At fields surpassing magnetocrystalline anisotropy, a 4f magnetic moment flip was still evidenced by HFC data in all samples at a compensation temperature Tcomp, which must necessarily be treated as distinct from T0 ( T0 may not even exist). Proper understanding of Tcomp should take account of thermomagnetic history effects.

  19. An investigation of the effects of history dependent damage in time dependent fracture mechanics, Phase 1, constant load conditions. Progress report

    SciTech Connect

    Brust, F.W.; Krishnaswamy, P.; Ghadiali, N.D.

    1991-11-14

    In the following section a brief review of constitutive models is presented along with the implications of using them in creep crack growth studies under variable loads. The model searched for this study, is discussed along with is special features that make is particularly suitable for this investigation. This model is based on the creep hardening surface and is particularly useful for variable and fully reversed load histories. In Section 3 an implicit finite element algorithm for this model is derived. Details regarding implementation of this method into FVP and existing FE program to study creep crack growth, are also discussed. The results of the algorithm are verified against closed form solutions for simple geometries in Section 4. Sources of error and differences between using explicit and implicit schemes are also presented. Section 5 compares the numerical results with experimental data for the case of combined tension and torsion and fully reversed load histories. Section 6 provides results of some of the constant load creep crack growth analyses that have been performed to date. Because a wealth of experimental data has been developed for creep crack under constant load conditions, the need to develop our own creep growth data for this study was minimal. Conclusions of the Phase 1 work as well as work planned for the future are discussed in Section 7. Finally, Sections 8 and 9 discuss publications and the Phase 2 effort, respectively. Finally, the implementation of large strain and friction/contact algorithms into the finite element code and the implementation of three additional non-linear constitutive laws and the Walker Model are not discussed here. The large strain algorithm is complete, the endochronic theory is nearly complete, while subroutines for the Bodner and Walker models were obtained from the agencies described above.

  20. Inter- and Intra-Specific Density-Dependent Effects on Life History and Development Strategies of Larval Mosquitoes

    PubMed Central

    Tsurim, Ido; Silberbush, Alon; Ovadia, Ofer; Blaustein, Leon; Margalith, Yoel

    2013-01-01

    We explored how inter- and intra-specific competition among larvae of two temporary-pool mosquito species, Culiseta longiareolata and Ochlerotatus caspius, affect larval developmental strategy and life history traits. Given that their larvae have similar feeding habits, we expected negative reciprocal inter-specific interactions. In a microcosm experiment, we found sex-specific responses of larval survival and development to both intra- and inter-specific larval competition. C. longiareolata was the superior competitor, reducing adult size and modifying larval developmental time of O. caspius. We observed two distinct waves of adult emergence in O. caspius, with clear sex-specific responses to its inter-specific competitor. In males, this pattern was not affected by C. longiareolata, but in females, the timing and average body size of the second wave strongly varied with C. longiareolata density. Specifically, in the absence of C. longiareolata, the second wave immediately followed the first wave. However, as C. longiareolata abundance increased, the second wave was progressively delayed and the resulting females tended to be larger. This study improves our understanding of the way intra- and inter-specific competition combine to influence the life histories of species making up temporary pond communities. It also provides strong evidence that not all individuals of a cohort employ the same strategies in response to competition. PMID:23469250

  1. Formation and evolution of early-type galaxies - III. Dependence of the star formation history on the total mass and initial overdensity

    NASA Astrophysics Data System (ADS)

    Merlin, E.; Chiosi, C.; Piovan, L.; Grassi, T.; Buonomo, U.; La Barbera, F.

    2012-12-01

    We investigate the influence of the initial overdensities and masses of proto-galaxies on their subsequent evolution (the star formation history in particular) to understand whether these key parameters are sufficient to account for the varied properties of the galactic populations. By means of fully hydrodynamical N-body simulations performed with the code EVOL, we produce 12 self-similar models of early-type galaxies of different initial masses and overdensities, and follow their evolution from the early epochs (detachment from the linear regime and Hubble flow at z ≥ 20) down to the stage when mass assembly is complete, i.e. z ≤ 1 (in some cases the models are calculated up to z = 0). The simulations include radiative cooling, star formation, stellar energy feedback, re-ionizing photo-heating background and chemical enrichment of the interstellar medium; we do not consider the possible presence of active nuclei. We find a strong correlation between the initial properties of the proto-haloes and their subsequent star formation histories. Massive (Mtot ≃ 1013 M⊙) haloes experience a single, intense burst of star formation (with rates ≥103 M⊙ yr-1) at early epochs, consistently with observations, with less pronounced dependence on the initial overdensity; intermediate-mass (Mtot ≃ 1011 M⊙) haloes have histories that strongly depend on their initial overdensity, whereas low-mass haloes (Mtot ≃ 109 M⊙) always have erratic, bursting like star-forming histories, due to the 'galactic breathing' phenomenon. The model galaxies have morphological, structural and chemical properties resembling those of real galaxies, even though some disagreement still occurs, likely a consequence of some numerical choices. We conclude that total mass and initial overdensity drive the star formation histories of early-type galaxies. The model galaxies belong to the so-called quasi-monolithic (or early hierarchical) scenario in the sense that the aggregation of lumps of

  2. The alveolitis of pulmonary sarcoidosis. Evaluation of natural history and alveolitis-dependent changes in lung function

    SciTech Connect

    Keogh, B.A.; Hunninghake, G.W.; Line, B.R.; Crystal, R.G.

    1983-08-01

    Current concepts of the pathogenesis of pulmonary sarcoidosis suggest that a mononuclear cell alveolitis, comprised of activated T-lymphocytes and activated alveolar macrophages, precedes and modulates the formation of granuloma and fibrosis. To evaluate the natural history of this alveolitis and determine the relationship it has to subsequent changes in lung function, 19 untreated patients with pulmonary sarcoidosis without extrapulmonary manifestations were studied with bronchoalveolar lavage, /sup 67/Ga scanning, and pulmonary function tests to evaluate lung T-cells, lung alveolar macrophages, and lung function, respectively. In patients with sarcoidosis, low intensity alveolitis (lung T-cells less than or equal to 28% of all lung effector cells and/or /sup 67/Ga scan negative) was much more common (80% of all observations) than high intensity alveolitis (lung T-cells greater than 28% and /sup 67/Ga scan positive, 20% of all observations). Conventional clinical, roentgenographic, or physiologic studies could not predict the alveolitis status. Interestingly, of the 51 alveolitis evaluations in the 19 patients, there were 24 occurrences (47%) where the alveolitis was ''split,'' i.e., /sup 67/Ga scans positive and T-cells low (39%) or /sup 67/Ga negative and T-cells high (8%). Most untreated patients with sarcoidosis without extrapulmonary symptoms may have some inflammatory processes ongoing in their alveolar structures. Overall, whenever a high intensity alveolitis episode occurred, it was followed by deterioration over the next 6 months in at least one lung function parameter. A low intensity alveolitis episode was followed by functional deterioration only 8% of the time. The alveolitis parameters (lavage and /sup 67/Ga scanning) clearly predicted prognosis. These observations should prove useful in understanding the natural history of pulmonary sarcoidosis, in staging patients with this disease, and in making rational therapy decisions.

  3. Life-history dependent relationships between body condition and immunity, between immunity indices in male Eurasian tree sparrows.

    PubMed

    Zhao, Yuliang; Li, Mo; Sun, Yanfeng; Wu, Wei; Kou, Guanqun; Guo, Lingling; Xing, Danning; Wu, Yuefeng; Li, Dongming; Zhao, Baohua

    2017-08-01

    In free-living animals, recent evidence indicates that innate, and acquired, immunity varies with annual variation in the demand for, and availability of, food resources. However, little is known about how animals adjust the relationships between immunity and body condition, and between innate and acquired immunity to optimize survival over winter and reproductive success during the breeding stage. Here, we measured indices of body condition (size-corrected mass [SCM], and hematocrit [Hct]), constitutive innate immunity (plasma total complement hemolysis activity [CH50]) and acquired immunity (plasma immunoglobulin A [IgA]), plus heterophil/lymphocyte (H/L) ratios, in male Eurasian tree sparrows (Passer montanus) during the wintering and the breeding stages. We found that birds during the wintering stage had higher IgA levels than those from the breeding stage. Two indices of body condition were both negatively correlated with plasma CH50 activities, and positively with IgA levels in wintering birds, but this was not the case in the breeding birds. However, there was no correlation between CH50 activities and IgA levels in both stages. These results suggest that the relationships between body condition and immunity can vary across life-history stage, and there are no correlations between innate and acquired immunity independent of life-history stage, in male Eurasian tree sparrows. Therefore, body condition indices predict immunological state, especially during the non-breeding stage, which can be useful indicators of individual immunocompetences for understanding the variations in innate and acquired immunity in free-living animals. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Effects of place identity, place dependence, and experience-use history on perceptions of recreation impacts in a natural setting.

    PubMed

    White, Dave D; Virden, Randy J; van Riper, Carena J

    2008-10-01

    It is generally accepted that recreation use in natural environments results in some degree of negative social and environmental impact. Environmental managers are tasked with mitigating the impact while providing beneficial recreation opportunities. Research on the factors that influence visitors' perceptions of environmental and social conditions is necessary to inform sound environmental management of protected natural areas. This study examines the effect of prior experience with the setting and two dimensions of place attachment (i.e., place identity and place dependence) on visitors' perceptions of three types of recreation impacts (i.e., depreciative behavior, environmental impacts, and recreation conflict). Principal components analysis, confirmatory factor analysis, and structural equation modeling were used to test the study hypotheses using data collected from 351 visitors through on-site questionnaires (response rate of 93 percent). The results show that prior experience exhibited a moderate and significant direct positive effect on place identity, place dependence, and visitors' perceptions of recreation impacts. Contrary to study hypotheses and prior research, neither place dependence nor place identity exhibited a significant effect on the dependent variables. The results show that prior experience causes visitors to be more sensitive to depreciative behaviors, environmental impacts, and recreation conflict. These findings raise concerns over potential visitor displacement and deterioration of site conditions. Implications for resource managers are discussed, which include education, modifying visitor use patterns, and site design strategies.

  5. ACOG Committee Opinion No. 659: The Use of Vaginal Estrogen in Women With a History of Estrogen-Dependent Breast Cancer.

    PubMed

    Farrell, Ruth

    2016-03-01

    Cancer treatment should address female-specific survivorship issues, including the hypoestrogenic- related adverse effects of cancer therapies or of natural menopause in survivors. Systemic and vaginal estrogen are widely used for symptomatic relief of vasomotor symptoms, sexual dysfunction, and lower urinary tract infections in the general population. However, given that some types of cancer are hormone sensitive, there are safety concerns about the use of local hormone therapy in women who currently have breast cancer or have a history of breast cancer. Nonhormonal approaches are the first-line choices for managing urogenital symptoms or atrophy-related urinary symptoms experienced by women during or after treatment for breast cancer. Among women with a history of estrogen-dependent breast cancer who are experiencing urogenital symptoms, vaginal estrogen should be reserved for those patients who are unresponsive to nonhormonal remedies. The decision to use vaginal estrogen may be made in coordination with a woman's oncologist. Additionally, it should be preceded by an informed decision-making and consent process in which the woman has the information and resources to consider the benefits and potential risks of low-dose vaginal estrogen. Data do not show an increased risk of cancer recurrence among women currently undergoing treatment for breast cancer or those with a personal history of breast cancer who use vaginal estrogen to relieve urogenital symptoms.

  6. ACOG Committee Opinion No. 659 Summary: The Use of Vaginal Estrogen in Women With a History of Estrogen-Dependent Breast Cancer.

    PubMed

    Farrell, Ruth

    2016-03-01

    Cancer treatment should address female-specific survivorship issues, including the hypoestrogenic- related adverse effects of cancer therapies or of natural menopause in survivors. Systemic and vaginal estrogen are widely used for symptomatic relief of vasomotor symptoms, sexual dysfunction, and lower urinary tract infections in the general population. However, given that some types of cancer are hormone sensitive, there are safety concerns about the use of local hormone therapy in women who currently have breast cancer or have a history of breast cancer. Nonhormonal approaches are the first-line choices for managing urogenital symptoms or atrophy-related urinary symptoms experienced by women during or after treatment for breast cancer. Among women with a history of estrogen-dependent breast cancer who are experiencing urogenital symptoms, vaginal estrogen should be reserved for those patients who are unresponsive to nonhormonal remedies. The decision to use vaginal estrogen may be made in coordination with a woman's oncologist. Additionally, it should be preceded by an informed decision-making and consent process in which the woman has the information and resources to consider the benefits and potential risks of low-dose vaginal estrogen. Data do not show an increased risk of cancer recurrence among women currently undergoing treatment for breast cancer or those with a personal history of breast cancer who use vaginal estrogen to relieve urogenital symptoms.

  7. The susceptibility of soil enzymes to inhibition by leaf litter tannins is dependent on the tannin chemistry, enzyme class and vegetation history.

    PubMed

    Triebwasser, Daniella J; Tharayil, Nishanth; Preston, Caroline M; Gerard, Patrick D

    2012-12-01

    By inhibiting soil enzymes, tannins play an important role in soil carbon (C) and nitrogen (N) mineralization. The role of tannin chemistry in this inhibitory process, in conjunction with enzyme classes and isoforms, is less well understood. Here, we compared the inhibition efficiencies of mixed tannins (MTs, mostly limited to angiosperms) and condensed tannins (CTs, produced mostly by gymnosperms) against the potential activity of β-glucosidase (BG), N-acetyl-glucosaminidase (NAG), and peroxidase in two soils that differed in their vegetation histories. Compared with CTs, MTs exhibited 50% more inhibition of almond (Prunus dulcis) BG activity and greater inhibition of the potential NAG activity in the gymnosperm-acclimatized soils. CTs exhibited lower BG inhibition in the angiosperm-acclimated soils, whereas both types of tannins exhibited higher peroxidase inhibition in the angiosperm soils than in gymnosperm soils. At all of the tested tannin concentrations, irrespective of the tannin type and site history, the potential peroxidase activity was inhibited two-fold more than the hydrolase activity and was positively associated with the redox-buffering efficiency of tannins. Our finding that the inhibitory activities and mechanisms of MTs and CTs are dependent on the vegetative history and enzyme class is novel and furthers our understanding of the role of tannins and soil isoenzymes in decomposition.

  8. Attention problems among children with a positive family history of alcohol abuse or dependence and controls. Prevalence and course for the period from preteen to early teen years.

    PubMed

    Barnow, Sven; Schuckit, Marc; Smith, Tom; Spitzer, Carsten; Freyberger, Harald-J

    2007-01-01

    This longitudinal study investigated the scope and course of attention problems over a period of time from preteen (ages 7-12 years) to early teen years (ages 13-17 years). We compared symptoms in subjects with and without a family history (FH) of alcohol abuse or dependence from among families without evidence of antisocial personality disorder. Evaluations of attention problems for the offspring were based on the Child Behavior Checklist and a validated semistructured interview carried out with the mother. The findings indicate no higher risk for attention problems and attention-deficit hyperactivity disorder (ADHD)-like symptoms in the children of families with an alcohol use disorder. Regarding the course of problems, the ADHD symptom count tended to decrease over time, especially for children without a FH of alcohol abuse or dependence. Further research will be needed to determine whether results can be replicated with families from different social strata and including subjects with the antisocial personality disorder.

  9. Recent History of Effector Use Modulates Practice-Dependent Changes in Corticospinal Excitability but Not Motor Learning.

    PubMed

    Hussain, Sara J; Darling, Warren G; Cole, Kelly J

    2016-01-01

    The theory of homeostatic metaplasticity has significant implications for human motor cortical plasticity and motor learning. Previous work has shown that the extent of recent effector use before exogenously-induced plasticity can affect the direction, magnitude and variability of aftereffects. However, the impact of recent effector use on motor learning and practice-dependent plasticity is not known. We hypothesized that reducing effector use for 8 hours via hand/wrist immobilization would facilitate practice-dependent changes in corticospinal excitability and TMS-evoked thumb movement kinematics, while also promoting 24-hour retention of a ballistic motor skill. Subjects participated in a crossover study involving two conditions. During the immobilization condition, subjects wore a splint that restricted motion of the left hand and thumb for 8 hours. While wearing the splint, subjects were instructed to avoid using their left hand as much as possible. During the control condition, subjects did not wear a splint at any time nor were they instructed to avoid hand use. After either an 8 hour period of immobilization or normal hand use, we collected MEP and TMS-evoked thumb movement recruitment curves, and subjects practiced a ballistic motor skill involving rapid thumb extension. After motor practice, MEP and TMS-evoked thumb movement recruitment curves were re-tested. Retention of the motor skill was tested 30 minutes and 24 hours after motor practice. Reduced effector use did not impact pre-practice corticospinal excitability but did facilitate practice-dependent changes in corticospinal excitability, and this enhancement was specific to the trained muscle. In contrast, reducing effector use did not affect practice-dependent changes in TMS-evoked thumb movements nor did it promote acquisition or retention of the skill. Finally, we detected some associations between pre-practice excitability levels, plasticity effects and learning effects, but these did not reach

  10. The relationship of suicide attempt history with childhood abuse and neglect, alexithymia and temperament and character dimensions of personality in substance dependents.

    PubMed

    Evren, Cuneyt; Evren, Bilge

    2006-01-01

    The aim of this study was to evaluate the prevalence of suicide in Turkish male substance dependents, and to investigate the relationship of suicide attempt history with childhood abuse and neglect, alexithymia, and temperament and character dimensions of personality. Participants were 154 consecutively admitted male substance dependents. Patients were investigated with the Childhood Abuse and Neglect Questionnaire, Toronto Alexithymia Scale (TAS-20) and Temperament and Character Inventory (TCI). Among substance-dependent patients, 28.6% was considered a group with suicide attempt history (SAH). Current age was lower and rate of being single was higher in the group with SAH. There were no significant differences between groups in terms of employment, educational status and duration of education. Rates of physical, emotional abuse and neglect, self-mutilation and being alexithymic were higher and ages at first substance use and regular substance use were lower in the group with SAH. Mean scores of "difficulty in identifying feelings" (DIF) and "difficulty in describing feelings" (DDF) subscale EOT of the TAS-20 were higher in the SAH group. Among temperament and character dimensions of the TCI, only "Self-directedness" and "Cooperativeness" were lower in SAH and there were no significant differences between groups in terms of other subscales. Age and Self-directedness score of TCI were determinants for suicide attempt. In particular, young drug users with low Self-directedness scores could be the target population in order to prevent suicidal behavior. This study also suggests that in substance-dependent patients, in the background of all suicidal behavior, childhood abuse and neglect must be evaluated.

  11. Satellite alignment. I. Distribution of substructures and their dependence on assembly history from n-body simulations

    SciTech Connect

    Wang, Yang Ocean; Lin, W. P.; Yu, Yu; Kang, X.; Dutton, Aaron; Macciò, Andrea V. E-mail: linwp@shao.ac.cn

    2014-05-01

    Observations have shown that the spatial distribution of satellite galaxies is not random, but aligned with the major axes of central galaxies. This alignment is dependent on galaxy properties, such that red satellites are more strongly aligned than blue satellites. Theoretical work conducted to interpret this phenomenon has found that it is due to the non-spherical nature of dark matter halos. However, most studies overpredict the alignment signal under the assumption that the central galaxy shape follows the shape of the host halo. It is also not clear whether the color dependence of alignment is due to an assembly bias or an evolution effect. In this paper we study these problems using a cosmological N-body simulation. Subhalos are used to trace the positions of satellite galaxies. It is found that the shapes of dark matter halos are mis-aligned at different radii. If the central galaxy shares the same shape as the inner host halo, then the alignment effect is weaker and agrees with observational data. However, it predicts almost no dependence of alignment on the color of satellite galaxies, though the late accreted subhalos show stronger alignment with the outer layer of the host halo than their early accreted counterparts. We find that this is due to the limitation of pure N-body simulations where satellite galaxies without associated subhalos ('orphan galaxies') are not resolved. These orphan (mostly red) satellites often reside in the inner region of host halos and should follow the shape of the host halo in the inner region.

  12. Landscape history and land-use dependent soil erosion in central Bosnia from the Bronze Age to Medieval Times

    NASA Astrophysics Data System (ADS)

    Wolters, Steffen; Enters, Dirk; Bittmann, Felix

    2010-05-01

    The inland areas of the northwestern Balkan peninsula and in particular of Bosnia and Herzegovina are poor in natural archives suitable for the reconstruction of past environmental changes and vegetation history. Consequently, palaeoenvironmental analyses are scarce with only three palynological studies available dating back to 1973, 1956 and 1934. Central Bosnia, however, is rich in archaeological heritage, featuring numerous prehistoric settlement sites along the river Bosna starting in the early Neolithic. This generates the need for palaeoenvironmental reconstructions to support and complement recent archaeological research in this area. Here we present results from a 450 cm gyttja-peat sequence from Seoce Jezero, a small mire located at 600 m NN on a plateau above a tributary of the river Bosna 30 km northwest of Sarajevo (central Bosnia). Fourteen AMS C-14 dates provide a robust time-depth-relationship which covers natural and anthropogenic environmental changes at Seoce Jezero from the Bronze Age to early Medieval Times. Pollen, macrofossil and geochemical analyses of 167 samples produce a high resolution record of land-use and vegetation change up to a half-decadal time scale. The palaeoenvironmental record starts ca. 1800 BC (3750 cal. BP) and reveals an initially relatively undisturbed landscape dominated by Fagus- and Quercus-Carpinus woodland. Anthropogenic influence is clearly visible from 1400 BC (3350 cal. BP) onwards and comprises woodland clearances, pasturing and crop cultivation. Pollen analyses confirm several consecutive phases of different land-use character and intensity. Phases of high land-use pressure culminated at the transition Bronze Age/Iron Age (1100 BC), the late Iron Age (400 BC), late Roman times (AD 300) and from AD 700 onwards. In between, stages of forest regeneration could be detected, most pronounced in the period between 70 BC and AD 150 (2020-1800 cal. BP), when anthropogenic influence virtually ceased. Whereas land use in

  13. Developmental momentum toward substance dependence: natural histories and pliability of risk factors in youth experiencing chronic stress.

    PubMed

    Ridenour, Ty A; Meyer-Chilenski, Sarah; Reid, Erin E

    2012-06-01

    Mitigation of substance use (SU) disorder (SUD) risk factors is a common goal of prevention. Research has clarified much about risk factors including their prediction of SU/SUD, associations with other etiological variables and mediation of SU outcomes. Greater understanding of the emergence of risk factors themselves may improve prevention. For example, in lieu of experimental data, the level of resistance to change of a risk factor (its pliability) could inform "dosage" of intervention needed to reduce the risk. Two attributes of 22 previously-documented predictors of SU/SUD were quantified: natural history (average age-related trend) and pliability (quantified using correlations between intercepts and growth parameters of hierarchical linear modeling trajectories). The longitudinal sample of 1147 8- through 16-year-olds were recruited from a northeastern summer camp for youth experiencing chronic stress due to one or more stressors (X¯=2.2stressors, SD=1.41) which typically last at least one year. Half were male, 69.3% were European-American, 8.5% were African-American, and the remaining were small proportions each of other or mixed races/ethnicities. Average trajectories of 21 predictors correspond to increasing SUD risk with age. Predictor pliability varied greatly, ranging from extremely high for School Commitment to extremely low for Peer Pressure Susceptibility. Results suggest different intervention strategies may be needed to manage risk factors over the long-term. To illustrate, maintaining a high school commitment appears to require boosters whereas reducing peer pressure susceptibility appears to require high initial "dosage" with less need for boosters. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  14. Evolutionary history of a vanishing radiation: isolation-dependent persistence and diversification in Pacific Island partulid tree snails.

    PubMed

    Lee, Taehwan; Li, Jingchun; Churchill, Celia K C; Foighil, Diarmaid Ó

    2014-09-24

    Partulid tree snails are endemic to Pacific high islands and have experienced extraordinary rates of extinction in recent decades. Although they collectively range across a 10,000 km swath of Oceania, half of the family's total species diversity is endemic to a single Eastern Pacific hot spot archipelago (the Society Islands) and all three partulid genera display highly distinctive distributions. Our goal was to investigate broad scale (range wide) and fine scale (within-Society Islands) molecular phylogenetic relationships of the two widespread genera, Partula and Samoana. What can such data tell us regarding the genesis of such divergent generic distribution patterns, and nominal species diversity levels across Oceania? Museum, captive (zoo) and contemporary field specimens enabled us to genotype 54 of the ~120 recognized species, including many extinct or extirpated taxa, from 14 archipelagoes. The genera Partula and Samoana are products of very distinct diversification processes. Originating at the western edge of the familial range, the derived genus Samoana is a relatively recent arrival in the far eastern archipelagoes (Society, Austral, Marquesas) where it exhibits a stepping-stone phylogenetic pattern and has proven adept at both intra-and inter- archipelago colonization. The pronounced east-west geographic disjunction exhibited by the genus Partula stems from a much older long-distance dispersal event and its high taxonomic diversity in the Society Islands is a product of a long history of within-archipelago diversification. The central importance of isolation for partulid lineage persistence and diversification is evident in time-calibrated phylogenetic trees that show that remote archipelagoes least impacted by continental biotas bear the oldest clades and/or the most speciose radiations. In contemporary Oceania, that isolation is being progressively undermined and these tree snails are now directly exposed to introduced continental predators

  15. Pollutant Dehalogenation Capability May Depend on the Trophic Evolutionary History of the Organism: PBDEs in Freshwater Food Webs

    PubMed Central

    Bartrons, Mireia; Grimalt, Joan O.; de Mendoza, Guillermo; Catalan, Jordi

    2012-01-01

    Organohalogen compounds are some of the most notorious persistent pollutants disturbing the Earth biosphere. Although human-made, these chemicals are not completely alien to living systems. A large number of natural organohalogens, part of the secondary metabolism, are involved in chemical trophic interactions. Surprisingly, the relationship between organisms’ trophic position and synthetic organohalogen biotransformation capability has not been investigated. We studied the case for polybromodiphenyl ethers (PBDE), a group of flame-retardants of widespread use in the recent years, in aquatic food webs from remote mountain lakes. These relatively simple ecosystems only receive pollution by atmospheric transport. A large predominance of the PBDE congener currently in use in Europe, BDE-209, largely dominated the PBDE composition of the basal resources of the food web. In contrast, primary consumers (herbivores and detritivores) showed a low proportion of BDE-209, and dominance of several less brominated congeners (e.g. BDE-100, BDE47). Secondary consumers (predators) showed large biomagnification of BDE-209 compare to other congeners. Finally, top predator fish characterized by low total PBDE concentrations. Examination of the bromine stable isotopic composition indicates that primary consumers showed higher PBDE biotransformation capability than secondary consumers. We suggest that the evolutionary response of primary consumers to feeding deterrents would have pre-adapted them for PBDE biotransformation. The observed few exceptions, some insect taxa, can be interpreted in the light of the trophic history of the evolutionary lineage of the organisms. Bromine isotopic composition in fish indicates that low PBDE values are due to not only biotransformation but also to some other process likely related to transport. Our finding illustrates that organohalogen compounds may strongly disturb ecosystems even at low concentrations, since the species lacking or having

  16. Pollutant dehalogenation capability may depend on the trophic evolutionary history of the organism: PBDEs in freshwater food webs.

    PubMed

    Bartrons, Mireia; Grimalt, Joan O; de Mendoza, Guillermo; Catalan, Jordi

    2012-01-01

    Organohalogen compounds are some of the most notorious persistent pollutants disturbing the Earth biosphere. Although human-made, these chemicals are not completely alien to living systems. A large number of natural organohalogens, part of the secondary metabolism, are involved in chemical trophic interactions. Surprisingly, the relationship between organisms' trophic position and synthetic organohalogen biotransformation capability has not been investigated. We studied the case for polybromodiphenyl ethers (PBDE), a group of flame-retardants of widespread use in the recent years, in aquatic food webs from remote mountain lakes. These relatively simple ecosystems only receive pollution by atmospheric transport. A large predominance of the PBDE congener currently in use in Europe, BDE-209, largely dominated the PBDE composition of the basal resources of the food web. In contrast, primary consumers (herbivores and detritivores) showed a low proportion of BDE-209, and dominance of several less brominated congeners (e.g. BDE-100, BDE47). Secondary consumers (predators) showed large biomagnification of BDE-209 compare to other congeners. Finally, top predator fish characterized by low total PBDE concentrations. Examination of the bromine stable isotopic composition indicates that primary consumers showed higher PBDE biotransformation capability than secondary consumers. We suggest that the evolutionary response of primary consumers to feeding deterrents would have pre-adapted them for PBDE biotransformation. The observed few exceptions, some insect taxa, can be interpreted in the light of the trophic history of the evolutionary lineage of the organisms. Bromine isotopic composition in fish indicates that low PBDE values are due to not only biotransformation but also to some other process likely related to transport. Our finding illustrates that organohalogen compounds may strongly disturb ecosystems even at low concentrations, since the species lacking or having scarce

  17. Fronto-temporal alterations and affect regulation in methamphetamine dependence with and without a history of psychosis.

    PubMed

    Uhlmann, Anne; Fouche, Jean-Paul; Koen, Nastassja; Meintjes, Ernesta M; Wilson, Don; Stein, Dan J

    2016-02-28

    Methamphetamine (MA) has been shown to have neurotoxic effects associated with brain structure changes and schizophrenia-like psychotic symptoms. Although these abnormalities may in turn be related to cognitive impairment and increased aggression, their association with affect dysregulation is less well studied. We investigated cortical thickness and subcortical volumes in 21 participants with MA dependence, 19 patients with MA-associated psychosis (MAP), and 19 healthy controls. Participants' affect regulation abilities were assessed through self-report scales on emotion reactivity (ERS) and difficulties in emotion regulation (DERS) and correlated with differences in cortical thickness. MAP patients showed thinner cortices in the fusiform and inferior temporal gyrus (ITG), orbitofrontal (OFC) and inferior frontal gyrus (IFG), and insula, compared to the MA group. MAP also showed significantly lower hippocampal volumes relative to MA and CTRL. Both clinical groups showed impairment in affect regulation, but only in MAP was this dysfunction associated with thinner cortices in ITG, OFC and IFG. Our findings suggest significant differences in cortical thickness in MA dependence with and without psychosis. Lower fronto-temporal cortical thickness and smaller hippocampal volumes in MAP are consistent with neuroimaging findings in other psychotic disorders, supporting the notion of MAP being a useful model of psychosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Environment-dependent reversal of a life history trade-off in the seed beetle Callosobruchus maculatus.

    PubMed

    Messina, F J; Fry, J D

    2003-05-01

    Environmental manipulations have consistently demonstrated a cost of reproduction in the capital-breeding seed beetle, Callosobruchus maculatus, as females deprived of seeds or mates lay fewer eggs and thereby increase their longevity. Yet fecundity and longevity tend to be positively correlated within populations, perhaps as a consequence of individual differences in resource acquisition. We conducted a split-brood experiment that combined a manipulation of seed availability (seeds present or absent) with a quantitative-genetic analysis of fecundity and lifespan in each environment. Each trait was significantly heritable in each environment. Seed availability not only altered mean fecundity and longevity between environments, but also modified how the traits were correlated within environments. The signs of both the phenotypic and genetic correlations switched from positive when seeds were present to negative when seeds were absent. This reversal persisted even after the effect of body mass (a potential indicator of resource acquisition) was statistically controlled. Cross-environment genetic correlations were positive but significantly less than one for each trait. We suggest that the reversal of the fecundity-longevity relationship depends on a shift in the relative importance of resource-acquisition and resource-allocation loci between environments. In particular, a cost of reproduction may be apparent at the individual level only when seeds are scarce or absent because differences in reproductive effort become large enough to overwhelm differences in resource acquisition. Despite their common dependence on resources acquired during larval stages, fecundity and lifespan in C. maculatus do not appear to be tightly coupled in a physiological or genetic sense.

  19. History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces.

    PubMed

    Li, Yan; Wang, Dengchao; Kvetny, Maksim M; Brown, Warren; Liu, Juan; Wang, Gangli

    2015-01-01

    The dynamics of ion transport at nanostructured substrate-solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Further advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current-potential (I-V) measurements and theoretical analyses. First, a unique non-zero I-V cross-point and pinched I-V curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Second, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging-discharging, as well as chemical and electrical energy conversion. The analysis of the emerging current-potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications.

  20. Ligand accessibility and bioactivity of a hormone–dendrimer conjugate depend on pH and pH history

    SciTech Connect

    Kim, Sung Hoon; Madak-Erdogan, Zeynep; Bae, Sung Chul; Carlson, Kathryn E.; Mayne, Christopher G.; Granick, Steve; Katzenellenbogen, Benita S.; Katzenellenbogen, John A.

    2015-07-17

    Estrogen conjugates with a polyamidoamine (PAMAM) dendrimer have shown remarkably selective regulation of the nongenomic actions of estrogens in target cells in this paper. In response to pH changes, however, these estrogen–dendrimer conjugates (EDCs) display a major morphological transition that alters the accessibility of the estrogen ligands that compromises the bioactivity of the EDC. A sharp break in dynamic behavior near pH 7 occurs for three different ligands on the surface of a PAMAM-G6 dendrimer: a fluorophore (tetramethylrhodamine [TMR]) and two estrogens (17α-ethynylestradiol and diphenolic acid). Collisional quenching and time-resolved fluorescence anisotropy experiments with TMR–PAMAM revealed high ligand shielding above pH 7 and low shielding below pH 7. Furthermore, when the pH was cycled from 8.5 (conditions of ligand–PAMAM conjugation) to 4.5 (e.g., endosome/lysosome) and through 6.5 (e.g., hypoxic environment) back to pH 8.5, the 17α-ethynylestradiol– and diphenolic acid–PAMAM conjugates experienced a dramatic, irreversible loss in cell stimulatory activity; dynamic NMR studies indicated that the hormonal ligands had become occluded within the more hydrophobic core of the PAMAM dendrimer. Thus, the active state of these estrogen–dendrimer conjugates appears to be metastable. Finally, this pH-dependent irreversible masking of activity is of considerable relevance to the design of drug conjugates with amine-bearing PAMAM dendrimers.

  1. History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces

    SciTech Connect

    Li, Yan; Wang, Dengchao; Kvetny, Maksim M.; Brown, Warren; Liu, Juan; Wang, Gangli

    2014-08-20

    The dynamics of ion transport at nanostructured substrate–solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current–potential (I–V) measurements and theoretical analyses. First, a unique non-zero I–V cross-point and pinched I–V curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Moreoever, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging–discharging, as well as chemical and electrical energy conversion. Our analysis of the emerging current–potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications.

  2. The evolutionary history and diverse physiological roles of the grapevine calcium-dependent protein kinase gene family.

    PubMed

    Chen, Fei; Fasoli, Marianna; Tornielli, Giovanni Battista; Dal Santo, Silvia; Pezzotti, Mario; Zhang, Liangsheng; Cai, Bin; Cheng, Zong-Ming

    2013-01-01

    Calcium-dependent protein kinases (CDPKs) are molecular switches that bind Ca(2+), ATP, and protein substrates, acting as sensor relays and responders that convert Ca(2+) signals, created by developmental processes and environmental stresses, into phosphorylation events. The precise functions of the CDPKs in grapevine (Vitis vinifera) are largely unknown. We therefore investigated the phylogenetic relationships and expression profiles of the 17 CDPK genes identified in the 12x grapevine genome sequence, resolving them into four subfamilies based on phylogenetic tree topology and gene structures. The origins of the CDPKs during grapevine evolution were characterized, involving 13 expansion events. Transcriptomic analysis using 54 tissues and developmental stages revealed three types of CDPK gene expression profiles: constitutive (housekeeping CDPKs), partitioned functions, and prevalent in pollen/stamen. We identified two duplicated CDPK genes that had evolved from housekeeping to pollen-prevalent functions and whose origin correlated with that of seed plants, suggesting neofunctionalization with an important role in pollen development and also potential value in the breeding of seedless varieties. We also found that CDPKs were involved in three abiotic stress signaling pathways and could therefore be used to investigate the crosstalk between stress responses.

  3. History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces

    DOE PAGES

    Li, Yan; Wang, Dengchao; Kvetny, Maksim M.; ...

    2014-08-20

    The dynamics of ion transport at nanostructured substrate–solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current–potential (I–V) measurements and theoretical analyses. First, a unique non-zero I–V cross-point and pinched I–Vmore » curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Moreoever, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging–discharging, as well as chemical and electrical energy conversion. Our analysis of the emerging current–potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications.« less

  4. Smaller right amygdala in Caucasian alcohol-dependent male patients with a history of intimate partner violence: a volumetric imaging study.

    PubMed

    Zhang, Lishu; Kerich, Mike; Schwandt, Melanie L; Rawlings, Robert R; McKellar, Joshua D; Momenan, Reza; Hommer, Daniel W; George, David T

    2013-05-01

    Studies have shown that various brain structure abnormalities are associated with chronic alcohol abuse and impulsive aggression. However, few imaging studies have focused on violent individuals with a diagnosis of alcohol dependence. The present study used volumetric magnetic resonance imaging (MRI) to compare the volumes of different structural components of prefrontal cortex and six subcortical structures in perpetrators of intimate partner violence with alcohol dependence (IPV-ADs), non-violent alcohol-dependent patients (non-violent ADs) and healthy controls (HCs). Caucasian men (n = 54), ages 24-55, who had participated in National Institutes of Alcohol Abuse and Alcoholism treatment programs, were grouped together as IPV-ADs (n = 27), non-violent ADs (n = 14) and HCs (n = 13). The MRI scan was performed at least 3 weeks from the participant's last alcohol use. T1-weighted images were used to measure the volumes of intracranial space, gray and white matter, orbitofrontal cortex, medial prefrontal cortex, lateral prefrontal cortex, and six subcortical structures. Results revealed that IPV-ADs, compared with non-violent ADs and HCs, had a significant volume reduction in the right amygdala. No significant volumetric difference was found in other structures. This finding suggests that structural deficits in the right amygdala may underlie impulsive types of aggression often seen in alcohol-dependent patients with a history of IPV. It adds to a growing literature suggesting that there are fundamental differences between alcohol-dependent patients with and without IPV. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.

  5. Ligand accessibility and bioactivity of a hormone–dendrimer conjugate depend on pH and pH history

    DOE PAGES

    Kim, Sung Hoon; Madak-Erdogan, Zeynep; Bae, Sung Chul; ...

    2015-07-17

    Estrogen conjugates with a polyamidoamine (PAMAM) dendrimer have shown remarkably selective regulation of the nongenomic actions of estrogens in target cells in this paper. In response to pH changes, however, these estrogen–dendrimer conjugates (EDCs) display a major morphological transition that alters the accessibility of the estrogen ligands that compromises the bioactivity of the EDC. A sharp break in dynamic behavior near pH 7 occurs for three different ligands on the surface of a PAMAM-G6 dendrimer: a fluorophore (tetramethylrhodamine [TMR]) and two estrogens (17α-ethynylestradiol and diphenolic acid). Collisional quenching and time-resolved fluorescence anisotropy experiments with TMR–PAMAM revealed high ligand shielding abovemore » pH 7 and low shielding below pH 7. Furthermore, when the pH was cycled from 8.5 (conditions of ligand–PAMAM conjugation) to 4.5 (e.g., endosome/lysosome) and through 6.5 (e.g., hypoxic environment) back to pH 8.5, the 17α-ethynylestradiol– and diphenolic acid–PAMAM conjugates experienced a dramatic, irreversible loss in cell stimulatory activity; dynamic NMR studies indicated that the hormonal ligands had become occluded within the more hydrophobic core of the PAMAM dendrimer. Thus, the active state of these estrogen–dendrimer conjugates appears to be metastable. Finally, this pH-dependent irreversible masking of activity is of considerable relevance to the design of drug conjugates with amine-bearing PAMAM dendrimers.« less

  6. Torque depression following active shortening is associated with a modulation of cortical and spinal excitation: a history-dependent study.

    PubMed

    Grant, Jordan; McNeil, Chris J; Bent, Leah R; Power, Geoffrey A

    2017-08-01

    The reduction in steady-state isometric torque following a shortening muscle action when compared to a purely isometric contraction at the same muscle length and level of activation is termed torque depression (TD). The purpose of this study was to investigate spinal and supraspinal neural responses during the TD state of a maximal voluntary activation of the ankle dorsiflexors. Thirteen subjects (10 male) were recruited for the study. To explore alterations in corticospinal excitability during voluntary muscle activation in the TD state, motor evoked potentials (MEPs), cervicomedullary motor evoked potentials (CMEPs), and maximal compound muscle action potentials (Mmax) were elicited during the isometric steady-state following active shortening (i.e., TD) and the purely isometric condition. A 15% reduction in steady-state isometric torque (P < 0.05) was observed following isokinetic shortening at 40°/sec. Although mean evoked responses (MEP and CMEP) were not different in the TD state as compared with purely isometric state, the changes in evoked responses were inversely related to one another depending on the level of TD These findings indicate that supraspinal and spinal responses are interrelated in the TD state. Furthermore, antagonist muscle coactivation during the isometric reference contraction was positively related to TD These findings suggest the possibility of a relationship between the central nervous system and TD in humans. Further work should be performed to definitively link TD to specific spinal interneurons. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  7. Parallel decrease in arterial distensibility and in endothelium-dependent dilatation in young women with a history of pre-eclampsia.

    PubMed

    Pàez, Olga; Alfie, José; Gorosito, Marta; Puleio, Pablo; de Maria, Marcelo; Prieto, Noemì; Majul, Claudio

    2009-10-01

    Pre-eclampsia not only complicates 5 to 8% of pregnancies but also increases the risk of maternal cardiovascular disease and mortality later in life. We analyzed three different aspects of arterial function (pulse wave velocity, augmentation index, and flow-mediated dilatation), in 55 nonpregnant, normotensive women (18-33 years old) according to their gestational history: 15 nulliparous, 20 with a previous normotensive, and 20 formerly pre-eclamptic pregnancy. Former pre-eclamptic women showed a significantly higher augmentation index and pulse wave velocity (P < 0.001 and P < 0.05, respectively) and lower flow-mediated dilatation (p = 0.01) compared to control groups. In contrast, sublingual nitroglycerine elicited a comparable vasodilatory response in the three groups. The augmentation index correlated significantly with pulse wave velocity and flow-mediated dilatation (R = 0.28 and R = -0.32, respectively, P < 0.05 for both). No significant correlations were observed between augmentation index or flow-mediated dilatation with age, body mass index (BMI), brachial blood pressure, heart rate, or metabolic parameters (plasma cholesterol, glucose, insulin, or insulin resistance). Birth weight maintained a significantly inverse correlation with the augmentation index (R = -0.51, p < 0.002) but not with flow-mediated dilatation. Our findings revealed a parallel decrease in arterial distensibility and endothelium-dependent dilatation in women with a history of pre-eclampsia compared to nulliparous women and women with a previous normal pregnancy. A high augmentation index was the most consistent alteration associated with a history of pre-eclampsia. The study supports the current view that the generalized arterial dysfunction associated with pre-eclampsia persists subclinically after delivery.

  8. The dependence of galaxy star formation histories on environment at 0.6 < z < 0.9

    NASA Astrophysics Data System (ADS)

    Patel, Shannon

    We used a low-dispersion prism (LDP) in IMACS on the 6.5 m Baade (Magellan I) telescope to obtain low resolution spectroscopy of galaxies with 18 < zAB < 23.3 mag over a ˜0.2 deg2 field. In contrast to spectra obtained through a traditional grating, the resolution of LDP spectra was a strong function of wavelength, with the spectral resolving power of the LDP varying from R ˜ 66 at 5000 A to R ˜ 15 at 8500 A. Stellar population synthesis models were fit to the relative flux calibrated LDP spectra and Subaru Suprime-Cam V Riz photometry in order to measure redshifts. We measured ˜10,000 redshifts to a precision of ˜1% in (1 + z). Given the emerging consensus regarding the key role of stellar mass in shaping the star formation histories (SFHs) of galaxies, we aimed to study stellar mass limited samples. Our z-band spectroscopic selection was critical in assembling samples to low mass limits at 0.6 < z < 0.9. Our final sample consisted of ˜1100 galaxies at 0.6 < z < 0.9 above a mass limit of M > 1.8 x 1010 M⊙ (log M/ M⊙ > 10.25). This mass limit roughly corresponds to 0.2M ⋆, thus reaching well below the knee of the Schechter mass function and also a factor of two below the threshold mass above which galaxy properties appear to be primarily determined by stellar mass. The rest-frame color of a galaxy serves as trace for the age of its stellar populations. We investigated the rest-frame u -- g color of galaxies as a function of local density in a redshift slice (0.80 < z < 0.87) containing the cluster RX J0152.7-1357 as well as several other groups. We find that the fraction of red galaxies increases at higher densities, reaching ˜90--100% in the cores of moderate mass groups, the same value as found in the center of RX J0152.7-1357, and suggesting the presence of older stellar populations in these high density environments. Because dust obscuration can make younger star forming galaxies (SFGs) appear red, we investigated the obscured star formation rates

  9. Sex differences in the genetic risk for schizophrenia: history of the evidence for sex-specific and sex-dependent effects.

    PubMed

    Goldstein, Jill M; Cherkerzian, Sara; Tsuang, Ming T; Petryshen, Tracey L

    2013-10-01

    Although there is a long history to examinations of sex differences in the familial (and specifically, genetic) transmission of schizophrenia, there have been few investigators who have systematically and rigorously studied this issue. This is true even in light of population and clinical studies identifying significant sex differences in incidence, expression, neuroanatomic and functional brain abnormalities, and course of schizophrenia. This review highlights the history of work in this arena from studies of family transmission patterns, linkage and twin studies to the current molecular genetic strategies of large genome-wide association studies. Taken as a whole, the evidence supports the presence of genetic risks of which some are sex-specific (i.e., presence in one sex and not the other) or sex-dependent (i.e., quantitative differences in risk between the sexes). Thus, a concerted effort to systematically investigate these questions is warranted and, as we argue here, necessary in order to fully understand the etiology of schizophrenia. © 2013 Wiley Periodicals, Inc.

  10. Match or mismatch: the influence of phenology on size-dependent life history and divergence in population structure

    USGS Publications Warehouse

    Borcherding, Jost; Beeck, Peter; DeAngelis, Donald L.; Scharf, Werner R.

    2010-01-01

    age cohort of the predator. 6. The results demonstrate that the switch between competitive interactions and a predator-prey relationship depended on phenology. This resulted in pronounced size differences in the YOY age cohort, which had far-reaching consequences for the entire predator population.

  11. Heat indicators of oxidative stress, inflammation and metal transport show dependence of cadmium pollution history in the liver of female zebrafish.

    PubMed

    Zhu, Qing-Ling; Guo, Sai-Nan; Yuan, Shuang-Shuang; Lv, Zhen-Ming; Zheng, Jia-Lang; Xia, Hu

    2017-10-01

    Environmental stressors such as high temperature and metal exposure may occur sequentially, simultaneously, previously in aquatic ecosystems. However, information about whether responses to high temperature depend on Cd exposure history is still unknown in fish. Zebrafish were exposed to 0 (group 1), 2.5 (group 2) and 5μg/L (group 3) cadmium (Cd) for 10 weeks, and then each group was subjected to Cd-free water maintained at 26°C and 32°C for 7days respectively. 26 indicators were used to compare differences between 26°C and 32°C in the liver of female zebrafish, including 5 biochemical indicators (activity of Cu/Zn-SOD, CAT and iNOS; LPO; MT protein), 8 molecular indicators of oxidative stress (mRNA levels of Nrf2, Cu/Zn-SOD, CAT, HSF1, HSF2, HSP70, MTF-1 and MT), 5 molecular indicators of inflammation (mRNA levels of IL-6, IL-1β, TNF-α, iNOS and NF-κB), 8 molecular indicators of metal transport (mRNA levels of, ZnT1, ZnT5, ZIP8, ZIP10, ATP7A, ATP7B and CTR1). All biochemical indicators were unchanged in group 1 and changed in group 2 and 3. Contrarily, differences were observed in almost all of molecular indicators of inflammation and metal transport in group 1, about half in group 2, and few in group 3. We also found that all molecular indicators of oxidative stress in group 2 and fewer in group 1 and 3 were significantly affected by heat. Our data indicated that heat indicators of oxidative stress, inflammation and metal transport showed dependence of previous cadmium exposure in the liver of zebrafish, emphasizing metal pollution history should be carefully considered when evaluating heat stress in fish. Copyright © 2017. Published by Elsevier B.V.

  12. A cost-effectiveness analysis of opioid substitution therapy upon prison release in reducing mortality among people with a history of opioid dependence.

    PubMed

    Gisev, Natasa; Shanahan, Marian; Weatherburn, Don J; Mattick, Richard P; Larney, Sarah; Burns, Lucy; Degenhardt, Louisa

    2015-12-01

    Although opioid substitution therapy (OST) immediately after prison release reduces mortality, the cost-effectiveness of treatment has not been examined. Therefore, we undertook a cost-effectiveness analysis of OST treatment upon prison release and the prevention of death in the first 6 months post-release. Population-based, retrospective data linkage study using records of OST entrants (1985-2010), charges and court appearances (1993-2011), prison episodes (2000-11) and death notifications (1985-2011). New South Wales, Australia. A cohort of 16,073 people with a history of opioid dependence released from prison for the first time between 1 January 2000 and 30 June 2011. OST treatment compared to no OST treatment at prison release. Mortality and costs (treatment, criminal justice system-court, penalties, prison-and the social costs of crime) were evaluated at 6 months post-release. Analyses included propensity score matching, bootstrapping and regression. A total of 13,468 individuals were matched (6734 in each group). Twenty (0.3%) people released onto OST died, compared with 46 people (0.7%) not released onto OST. The final average costs were lower for the group that received OST post-release ($7206 versus $14,356). The incremental cost-effectiveness ratio showed that OST post-release was dominant, incurring lower costs and saving more lives. The probability that OST post-release is cost-effective per life-year saved is 96.7% at a willingness to pay of $500. Opioid substitution treatment (compared with no such treatment), given on release from prison to people with a history of opioid dependence, is cost-effective in reducing mortality in the first 6 months of release. © 2015 Society for the Study of Addiction.

  13. Ontogenetic timing as a condition-dependent life history trait: High-condition males develop quickly, peak early, and age fast.

    PubMed

    Hooper, Amy K; Spagopoulou, Foteini; Wylde, Zachariah; Maklakov, Alexei A; Bonduriansky, Russell

    2017-03-01

    Within-population variation in ageing remains poorly understood. In males, condition-dependent investment in secondary sexual traits may incur costs that limit ability to invest in somatic maintenance. Moreover, males often express morphological and behavioral secondary sexual traits simultaneously, but the relative effects on ageing of investment in these traits remain unclear. We investigated the condition dependence of male life history in the neriid fly Telostylinus angusticollis. Using a fully factorial design, we manipulated male early-life condition by varying nutrient content of the larval diet and, subsequently, manipulated opportunity for adult males to interact with rival males. We found that high-condition males developed more quickly and reached their reproductive peak earlier in life, but also experienced faster reproductive ageing and died sooner than low-condition males. By contrast, interactions with rival males reduced male lifespan but did not affect male reproductive ageing. High-condition in early life is therefore associated with rapid ageing in T. angusticollis males, even in the absence of damaging male-male interactions. Our results show that abundant resources during the juvenile phase are used to expedite growth and development and enhance early-life reproductive performance at the expense of late-life performance and survival, demonstrating a clear link between male condition and ageing.

  14. Lifetime history of traumatic events in an American Indian community sample: heritability and relation to substance dependence, affective disorder, conduct disorder and PTSD.

    PubMed

    Ehlers, Cindy L; Gizer, Ian R; Gilder, David A; Yehuda, Rachael

    2013-02-01

    American Indians appear to experience a higher rate of traumatic events than what has been reported in general population surveys. American Indians also suffer higher alcohol related death rates than any other ethnic group in the U.S. population. Therefore efforts to delineate factors which may uniquely contribute to increased likelihood of trauma, post traumatic stress disorder (PTSD), and substance use disorders (SUD) over the lifetime in American Indians are important because of the high burden of morbidity and mortality that they pose to American Indian communities. Participants were American Indians recruited from reservations that were assessed with the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA), family history assessment and the stressful-life-events scale. Of the 309 participants, equivalent numbers of men and women (94%) reported experiencing traumas; however, a larger proportion of women received a PTSD diagnosis (38%) than men (29%). Having experienced multiple trauma and sexual abuse were most highly associated with PTSD. Having experienced assaultive trauma and having PTSD symptoms were both found to be moderately heritable (30-50%). Logistic regression revealed that having an anxiety and/or affective disorder and having a substance dependent diagnosis, but not having antisocial personality disorder/conduct disorder, were significantly correlated with having a diagnosis of PTSD. These studies suggest that trauma is highly prevalent in this American Indian community, it is heritable, is associated with PTSD, affective/anxiety disorders and substance dependence. Additionally, trauma, PTSD and substance dependence appear to all co-emerge in early adulthood in this high-risk population. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Stress-related salivary alpha-amylase (sAA) activity in alcohol dependent patients with and without a history of childhood maltreatment.

    PubMed

    Muehlhan, Markus; Höcker, Anja; Höfler, Michael; Wiedemann, Klaus; Barnow, Sven; Schäfer, Ingo

    2017-06-01

    Alcohol-dependent (AD) patients with a history of childhood maltreatment (CM) have shown a more severe clinical profile and a higher risk of relapse than those without CM. It was hypothesized that stress responsivity plays an important role in moderating the relationship between CM and AD. Surprisingly, systematic investigations about the stress responsivity in AD patients with CM are rare. This study compared physiological and subjective stress responses in AD patients with and without CM as well as in healthy controls with and without CM. A total of 130 participants performed the Trier Social Stress Test (TSST). Physiological stress reactivity related to the noradrenergic system was assessed by salivary alpha-amylase (sAA) activity. Subjective ratings of anxiety, nervousness, distress, and mood were rated on visual analogue scales. AD patients showed significantly lower stress-related sAA activity than healthy controls (p ≤ 0.024; z ≥ 1.97). A different pattern was found in the subjective ratings. In particular, anticipatory anxiety revealed a clear effect of CM (p ≤ 0.005; z ≥ 2.43) but no difference between AD patients and healthy controls (p > 0.05). After the TSST, distress ratings differed between AD patients with CM and AD patients without CM (p ≤ 0.009; z ≥ 2.61). The discrepancy between physiological responsivity and subjective stress experiences may account for an increased inability to cope with stressful situations, which in turn might explain the enhanced risk of relapse in AD patients with a history of CM during early abstinence.

  16. Effects of Sex, Drinking History, and Omega-3 and Omega-6 Fatty Acids Dysregulation on the Onset of Liver Injury in Very Heavy Drinking Alcohol-Dependent Patients

    PubMed Central

    Vatsalya, Vatsalya; Song, Ming; Schwandt, Melanie L.; Cave, Matthew C.; Barve, Shirish S.; George, David T.; Ramchandani, Vijay A.; McClain, Craig J.

    2017-01-01

    Background Heavy alcohol consumption frequently causes liver inflammation/injury, and certain fatty acids (FAs) may be involved in this liver pathology. In this study, we evaluated the association of heavy drinking and the changes in the FA levels involved in the ω-6 (pro-inflammatory) and ω-3 (anti-inflammatory) state in alcohol-dependent (AD) patients who had no clinical manifestations of liver injury. We aimed to identify sex-based differences in patients with mild or no biochemical evidence of liver injury induced by heavy drinking. Methods A total of 114 heavy drinking AD female and male patients aged 21 to 65 years without clinical manifestations of liver injury, who were admitted to an alcohol dependence treatment program, were grouped by the alanine aminotransferase (ALT) levels: ≤40 IU/l, as no liver injury (GR.1), and >40 IU/l, as mild liver injury (GR.2). Patients were actively drinking until the day of admission. Comprehensive metabolic panel, comprehensive FA panel, and drinking history data were evaluated. Results Elevated ALT and aspartate aminotransferase (AST) showed close association with markers of heavy alcohol intake. In the patients with mild biochemical liver injury (GR.2), females showed significantly higher AST level than males. Significant association of AST and total drinks in past 90 days (TD90) in females, and AST and heavy drinking days in past 90 days (HDD90) in males was observed. The ω-6:ω-3 ratio showed a significant pro-inflammatory response only in females with mild liver injury (GR.2) when adjusted by drinking history marker, TD90. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were increased in males with liver injury, while females did not show any comparable rise in EPA; and DHA levels were lower. Conclusions Measures of heavy drinking, TD90 and HDD90, predicted changes in liver injury. Changes in the ω-3 and ω-6 FA levels and the ω-6:ω-3 ratio showed a pro-inflammatory shift in patients with biochemical

  17. Effects of Sex, Drinking History, and Omega-3 and Omega-6 Fatty Acids Dysregulation on the Onset of Liver Injury in Very Heavy Drinking Alcohol-Dependent Patients.

    PubMed

    Vatsalya, Vatsalya; Song, Ming; Schwandt, Melanie L; Cave, Matthew C; Barve, Shirish S; George, David T; Ramchandani, Vijay A; McClain, Craig J

    2016-10-01

    Heavy alcohol consumption frequently causes liver inflammation/injury, and certain fatty acids (FAs) may be involved in this liver pathology. In this study, we evaluated the association of heavy drinking and the changes in the FA levels involved in the ω-6 (pro-inflammatory) and ω-3 (anti-inflammatory) state in alcohol-dependent (AD) patients who had no clinical manifestations of liver injury. We aimed to identify sex-based differences in patients with mild or no biochemical evidence of liver injury induced by heavy drinking. A total of 114 heavy drinking AD female and male patients aged 21 to 65 years without clinical manifestations of liver injury, who were admitted to an alcohol dependence treatment program, were grouped by the alanine aminotransferase (ALT) levels: ≤40 IU/l, as no liver injury (GR.1), and >40 IU/l, as mild liver injury (GR.2). Patients were actively drinking until the day of admission. Comprehensive metabolic panel, comprehensive FA panel, and drinking history data were evaluated. Elevated ALT and aspartate aminotransferase (AST) showed close association with markers of heavy alcohol intake. In the patients with mild biochemical liver injury (GR.2), females showed significantly higher AST level than males. Significant association of AST and total drinks in past 90 days (TD90) in females, and AST and heavy drinking days in past 90 days (HDD90) in males was observed. The ω-6:ω-3 ratio showed a significant pro-inflammatory response only in females with mild liver injury (GR.2) when adjusted by drinking history marker, TD90. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were increased in males with liver injury, while females did not show any comparable rise in EPA; and DHA levels were lower. Measures of heavy drinking, TD90 and HDD90, predicted changes in liver injury. Changes in the ω-3 and ω-6 FA levels and the ω-6:ω-3 ratio showed a pro-inflammatory shift in patients with biochemical liver injury with a significant

  18. Bayesian deterministic decision making: a normative account of the operant matching law and heavy-tailed reward history dependency of choices

    PubMed Central

    Saito, Hiroshi; Katahira, Kentaro; Okanoya, Kazuo; Okada, Masato

    2014-01-01

    The decision making behaviors of humans and animals adapt and then satisfy an “operant matching law” in certain type of tasks. This was first pointed out by Herrnstein in his foraging experiments on pigeons. The matching law has been one landmark for elucidating the underlying processes of decision making and its learning in the brain. An interesting question is whether decisions are made deterministically or probabilistically. Conventional learning models of the matching law are based on the latter idea; they assume that subjects learn choice probabilities of respective alternatives and decide stochastically with the probabilities. However, it is unknown whether the matching law can be accounted for by a deterministic strategy or not. To answer this question, we propose several deterministic Bayesian decision making models that have certain incorrect beliefs about an environment. We claim that a simple model produces behavior satisfying the matching law in static settings of a foraging task but not in dynamic settings. We found that the model that has a belief that the environment is volatile works well in the dynamic foraging task and exhibits undermatching, which is a slight deviation from the matching law observed in many experiments. This model also demonstrates the double-exponential reward history dependency of a choice and a heavier-tailed run-length distribution, as has recently been reported in experiments on monkeys. PMID:24624077

  19. Bayesian deterministic decision making: a normative account of the operant matching law and heavy-tailed reward history dependency of choices.

    PubMed

    Saito, Hiroshi; Katahira, Kentaro; Okanoya, Kazuo; Okada, Masato

    2014-01-01

    The decision making behaviors of humans and animals adapt and then satisfy an "operant matching law" in certain type of tasks. This was first pointed out by Herrnstein in his foraging experiments on pigeons. The matching law has been one landmark for elucidating the underlying processes of decision making and its learning in the brain. An interesting question is whether decisions are made deterministically or probabilistically. Conventional learning models of the matching law are based on the latter idea; they assume that subjects learn choice probabilities of respective alternatives and decide stochastically with the probabilities. However, it is unknown whether the matching law can be accounted for by a deterministic strategy or not. To answer this question, we propose several deterministic Bayesian decision making models that have certain incorrect beliefs about an environment. We claim that a simple model produces behavior satisfying the matching law in static settings of a foraging task but not in dynamic settings. We found that the model that has a belief that the environment is volatile works well in the dynamic foraging task and exhibits undermatching, which is a slight deviation from the matching law observed in many experiments. This model also demonstrates the double-exponential reward history dependency of a choice and a heavier-tailed run-length distribution, as has recently been reported in experiments on monkeys.

  20. State dependent gene-environment interaction: serotonin transporter gene-child abuse interaction associated with suicide attempt history among depressed psychiatric inpatients.

    PubMed

    Shinozaki, Gen; Romanowicz, Magdalena; Passov, Victoria; Rundell, James; Mrazek, David; Kung, Simon

    2013-05-01

    The serotonin transporter gene polymorphism (5HTTLPR) and child abuse history have been associated with an increased suicide risk for general population, but such association is not clear among psychiatric depressed inpatients. A chart review identified 422 depressed inpatients genotyped for 5HTTLPR. Child abuse and suicide attempt history were recorded. The relationship between 5HTTLPR, child abuse, and suicide attempts were analyzed. There was a significant relationship between 5HTTLPR and history of suicide attempt (the long/long versus the short carriers, 47.9% versus 31.8%, p=0.0015). There was also a significant main effect from child abuse history (abused versus not abused, 45.1% versus 28.6%, p=0.0001). The likelihood ratio test showed a significant result for the l/l genotype group with child abuse history (odds ratio 4.11, χ2 = 23.5, p<0.0001). No significant result was obtained from other groups. This is a retrospective study based on chart review. Replication with more standardized research setting for measurements of child abuse history and suicide attempt history is needed. The rs25531 variant among a long allele (long-A and long-G) of 5HTTLPR was not genotyped. In addition to the direct effect from 5HTTLPR and child abuse history, an interaction between the 5HTTLPR gene and child abuse history influenced psychiatric profiles of depressed inpatients. Contrary to the widely recognized "reactivity" associated with the short allele, our patients with the l/l genotype and child abuse history showed significantly severer psychiatric pathology than short carriers with child abuse history. Published by Elsevier B.V.

  1. Fire ecology of C3 and C4 grasses depends on evolutionary history and frequency of burning but not photosynthetic type.

    PubMed

    Ripley, Brad; Visser, Vernon; Christin, Pascal-Antoine; Archibald, Sally; Martin, Tarryn; Osborne, Colin

    2015-10-01

    Grasses using the C4 photosynthetic pathway dominate frequently burned savannas, where the pathway is hypothesized to be adaptive. However, independent C4 lineages also sort among different fire environments. Adaptations to fire may thus depend on evolutionary history, which could be as important as the possession of the C4 photosynthetic pathway for life in these environments. Here, using a comparative pot experiment and controlled burn, we examined C3 and C4 grasses belonging to four lineages from the same regional flora, and asked the following questions: Do lineages differ in their responses to fire, are responses consistent between photosynthetic types, and are responses related to fire frequency in natural habitats? We found that in the C4 Andropogoneae lineage, frost killed a large proportion of aboveground biomass and produced a large dry fuel load, which meant that only a small fraction of the living tissue was lost in the fire. C3 species from the Paniceae and Danthonioideae lineages generated smaller fuel loads and lost more living biomass, while species from the C4 lineage Aristida generated the smallest fuel loads and lost the most living tissue. Regrowth after the fire was more rapid and complete in the C4 Andropogoneae and C3 Paniceae, but incomplete and slower in the C3 Danthonioideae and C4 Aristida. Rapid recovery was associated with high photosynthetic rates, high specific leaf area, delayed flowering, and frequent fires in natural habitats. Results demonstrated that phylogenetic lineage was more important than photosynthetic type in determining the fire response of these grasses and that fire responses were related to the frequency that natural habitats burned.

  2. Possible scenarios for slip history in Hyuga-nada and Bungo channel regions depending on occurrences of Nankai Earthquakes in southwest Japan, based on numerical simulations

    NASA Astrophysics Data System (ADS)

    Nakata, R.; Hyodo, M.; Hori, T.

    2013-12-01

    using the composite law, which is a type of rate- and state-dependent friction law. In our simulation, Nankai Earthquakes of Mw8.2 occur independently with the average recurrence interval of 150years. The Hyuga-nada earthquakes of Mw7.5 occur with the recurrence intervals of 48 to 209 years and the average is 117 yrs. SSE patch coseismically slips simultaneous to both Nankai and Hyuga-nada earthquakes. And once for 500-600 years, rupture of the Nankai Earthquake (Mw8.7) extends to west, including the source of Hyuga-nada earthquakes. As a result, quiescence of SSEs continues for more than 200 years after the larger Nankai earthquake. After the quiescence period, SSEs repeatedly occur every eight years. Current seismological and geological findings are generally consistent with some characteristics during this scenario except for recurrence intervals of Hyuga-nada earthquakes. This scenario suggests that historical records in Hyuga-nada to Bungo channel should get reconsidered at least between 1707 and 1968. Further evidences for slip history in these regions are required to utilize information from such simulations for forecasting earthquake.

  3. Family History

    MedlinePlus

    ... Aneurysms » Diagnosis » Family History A- A A+ Family History Familial intracranial aneurysms are generally defined as the ... patients with an Intracranial Aneurysm (IA) have a history of smoking at some time in their life. ...

  4. Intellectual History, Social History, Cultural History...and Our History.

    ERIC Educational Resources Information Center

    Nord, David Paul

    1990-01-01

    Defines and explores the links among intellectual, social, and cultural history. Warns that an adequate foundation must be laid in the economic and institutional social history of mass media before communication historians jump into cultural history. (SR)

  5. Tracing the Mass-Dependent Star Formation History of Late-Type Galaxies using X-ray Emission: Results from the CHANDRA Deep Fields

    NASA Technical Reports Server (NTRS)

    Lehmer, B.D; Brandt, W.N.; Schneider, D.P.; Steffen, A.T.; Alexander, D.M.; Bell, E.F.; Hornschemeier, A.E.; McIntosh, D.H.; Bauer, F.E.; Gilli, R.; hide

    2008-01-01

    We report on the X-ray evolution over the last approx.9 Gyr of cosmic history (i.e., since z = 1.4) of late-type galaxy populations in the Chandra Deep Field-North and Extended Chandra Deep Field-South (CDF-N and E-CDF-S. respectively; jointly CDFs) survey fields. Our late-type galaxy sample consists of 2568 galaxies. which were identified using rest-frame optical colors and HST morphologies. We utilized X-ray stacking analyses to investigate the X-ray emission from these galaxies, emphasizing the contributions from normal galaxies that are not dominated by active galactic nuclei (AGNs). Over this redshift range, we find significant increases (factors of approx. 5-10) in the X-ray-to-optical mean luminosity ratio (L(sub x)/L(sub B)) and the X-ray-to-stellar-mass mean ratio (L(sub x)/M(sub *)) for galaxy populations selected by L(sub B) and M(sub *), respectively. When analyzing galaxy samples selected via SFR, we find that the mean X-ray-to-SFR ratio (L(sub x)/SFR) is consistent with being constant over the entire redshift range for galaxies with SFR = 1-100 Solar Mass/yr, thus demonstrating that X-ray emission can be used as a robust indicator of star-formation activity out to z approx. 1.4. We find that the star-formation activity (as traced by X-ray luminosity) per unit stellar mass in a given redshift bin increases with decreasing stellar mass over the redshift range z = 0.2-1, which is consistent with previous studies of how star-formation activity depends on stellar mass. Finally, we extend our X-ray analyses to Lyman break galaxies at z approx. 3 and estimate that L(sub x)/L(sub B) at z approx. 3 is similar to its value at z = 1.4.

  6. Tropical mountain glaciers on Mars: Altitude-dependence of ice accumulation, accumulation conditions, formation times, glacier dynamics, and implications for planetary spin-axis/orbital history

    NASA Astrophysics Data System (ADS)

    Fastook, James L.; Head, James W.; Marchant, David R.; Forget, Francois

    2008-12-01

    Fan-shaped deposits up to ˜166,000 km in area are found on the northwest flanks of the huge Tharsis Montes volcanoes in the tropics of Mars. Recent spacecraft data have confirmed earlier hypotheses that these lobate deposits are glacial in origin. Increased knowledge of polar-latitude terrestrial glacial analogs in the Antarctic Dry Valleys has been used to show that the lobate deposits are the remnants of cold-based glaciers that formed in the extremely cold, hyper-arid climate of Mars. Mars atmospheric general circulation models (GCM) show that these glaciers could form during periods of high obliquity when upwelling and adiabatic cooling of moist air favor deposition of snow on the northwest flanks of the Tharsis Montes. We present a simulation of the Tharsis Montes ice sheets produced by a static accumulation pattern based on the GCM results and compare this with the nature and extent of the geologic deposits. We use the fundamental differences between the atmospheric snow accumulation environments (mass balance) on Earth and Mars, geological observations and ice-sheet models to show that two equilibrium lines should characterize ice-sheet mass balance on Mars, and that glacial accumulation should be favored on the flanks of large volcanoes, not on their summits as seen on Earth. Predicted accumulation rates from such a parameterization, together with sample spin-axis obliquity histories, are used to show that obliquity in excess of 45° and multiple 120,000 year obliquity cycles are necessary to produce the observed deposits. Our results indicate that the formation of these deposits required multiple successive stages of advance and retreat before their full extent could be reached, and thus imply that spin-axis obliquity remained at these high values for millions of years during the Late Amazonian period of Mars history. Spin-axis obliquity is one of the main factors in the distribution and intensity of solar insolation, and thus in determining the climate

  7. Tropical Mountain Glaciers on Mars: Altitude-Dependence of Ice Accumulation, Accumulation Conditions, Formation Times, Glacier Dynamics, and Implications for Planetary Spin- Axis/Orbital History

    NASA Astrophysics Data System (ADS)

    Fastook, J. L.; Head, J. W.; Marchant, D. R.

    2007-12-01

    Lobate deposits up to ~166,000 km2 in area are found on the northwest flanks of the huge Tharsis Montes volcanos in the tropics of Mars. Recent spacecraft data have confirmed earlier hypotheses that these lobate deposits are glacial in origin. Increased knowledge of polar-latitude terrestrial glacial analogs in the Antarctic Dry Valleys has been used to show that the lobate deposits are the remnants of cold-based glaciers that formed in the extremely cold, hyper-arid climate of Mars. Mars atmospheric general circulation models (GCM) show that these glaciers form during periods of high obliquity when upwelling and adiabatic cooling of moist polar air favor deposition of snow on the northwest flanks of the Tharsis Montes. We present a simulation of the Tharsis Montes ice sheets produced by a static accumulation pattern based on the GCM results and compare this with the nature and extent of the geologic deposits. We use the fundamental differences between the atmospheric snow accumulation environments (mass balance) on Earth and Mars, geological observations and ice sheet models to show that two equilibrium lines should characterize ice sheet mass balance on Mars, and that glacial accumulation should be favored on the flanks of large volcanos, not on their summits as seen on Earth. Predicted accumulation rates from such a parameterization, together with sample spin-axis obliquity histories, are used to show that mean obliquity in excess of 45 degrees and multiple 120,000 year obliquity cycles are necessary to produce the observed deposits. Our results indicate that the formation of these deposits required multiple successive stages of advance and retreat before their full extent could be reached, and thus imply that spin-axis obliquity remained at these high values for millions of years during the Late Amazonian period of Mars history. Spin-axis obliquity is one of the main factors in the distribution and intensity of solar insolation, and thus in determining the

  8. Microscopic mechanism of path-dependence on charge-discharge history in lithium iron phosphate cathode analysis using scanning transmission electron microscopy and electron energy-loss spectroscopy spectral imaging

    NASA Astrophysics Data System (ADS)

    Honda, Yoshitake; Muto, Shunsuke; Tatsumi, Kazuyoshi; Kondo, Hiroki; Horibuchi, Kayo; Kobayashi, Tetsuro; Sasaki, Tsuyoshi

    2015-09-01

    We revisited the "path-dependence" problem, i.e., the differing polarization observed in LiFePO4 cathode charge/discharge curves depending on the electrochemical treatment history of the material. The phase distributions of the active material particles with different charge/discharge histories in the LiFePO4 cathode were investigated through spectral imaging (SI) using scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). The STEM-EELS-SI experiments revealed that LiFePO4 (LFP) and FePO4 (FP) almost always coexist in the individual primary particles of Li0.5FePO4 (50% state of charge (SOC)) electrodes, forming core/shell structures. This is unlike the conventional domino-cascade model, in that LFP-inside/FP-outside is observed in the lithium-extracted Li0.5FePO4 particles, whereas FP-inside/LFP-outside is seen in the lithium-inserted Li0.5FePO4 particles. We examined the particle-size dependence of the core/total volume ratio of each Li0.5FePO4 particle, and the essential features of the path-dependent charge/discharge curves were semi-quantitatively reproduced by a simple static model that considered the ionic conductivity of the shell phase.

  9. Doing History.

    ERIC Educational Resources Information Center

    Beery, Robert W.

    When elementary students examine primary sources and local historical sites to gain firsthand information about life in the past, history becomes more relevant, exciting, and enjoyable. To help students understand that history is not just what is in a textbook, this student resource book focuses on making them aware that history exists all around…

  10. Community History.

    ERIC Educational Resources Information Center

    Lewis, Helen M.

    1997-01-01

    Recounts the experience of researching community history in Ivanhoe, Virginia, between 1987 and 1990. The Ivanhoe History Project involved community members in collecting photographs, memorabilia, and oral histories of their town. Subsequent published volumes won the W. D. Weatherford Award and inspired a quilt exhibit and a theatrical production.…

  11. Analysis of DSC thermal curves for assigning a characteristic glass transition temperature, dependent on either the type or thermal history of the polymer

    SciTech Connect

    Saffell, J.R.

    1994-09-01

    DSC was used to study the thermal curve characteristics of four classical polymer glasses: polycarbonate (PC), anionic polystyrene (aPS), polysulfone, and polymethyl methacrylate (PMMA). The onset, peak, and fictive temperatures as well as endotherm characteristics were studied over two decades of heating and cooling rates. Assuming that the fictive temperature is independent of heating rate, the usefulness of T{sub onset} and ambiguity of T{sub peak} are demonstrated. The useful [heat/cool] ratio allows use of T{sub onset} to calculate the effective cooling rate of the sample (which is easier to calculate than T{sub fictive}). Comparison with results from annealed samples are shown. The fictive and onset temperatures can be used together to improve the reliability of glass temperature characterization and results are surprisingly constant between the four different types of glasses, leading to a method of providing a single temperature to characterize the thermal history/morphology using a DSC thermal curve. The peak temperature is nearly independent of thermal history, and so provides a characterization parameter that is insensitive to manufacturing and molding procedures.

  12. Inferring the evolutionary history of Mo-dependent nitrogen fixation from phylogenetic studies of nifK and nifDK.

    PubMed

    Hartmann, Linda S; Barnum, Susan R

    2010-07-01

    The ability to fix nitrogen is widely, but sporadically distributed among the Bacteria and Archaea suggesting either a vertically inherited, ancient function with widespread loss across genera or an adaptive feature transferred laterally between co-inhabitants of nitrogen-poor environments. As previous phylogenetic studies of nifH and nifD have not completely resolved the evolutionary history of nitrogenase, sixty nifD, nifK, and combined nifDK genes were analyzed using Bayesian, maximum likelihood, and parsimony algorithms to determine whether the individual and combined datasets could provide additional information. The results show congruence between the 16S and nifDK phylogenies at the phyla level and generally support vertical descent with loss. However, statistically significant differences between tree topographies suggest a complex evolutionary history with the underlying pattern of vertical descent obscured by recurring lateral transfer events and different patterns of evolution between the genes. Results support inheritance from the Last Common ancestor or an ancient lateral transfer of the nif genes between Bacteria and Archaea, ongoing gene transfer between cohabitants of similar biogeographic regions, acquisition of nitrogen-fixing capability via symbiosis islands, possible xenologous displacement of one gene in the operon, and possible retention of ancestral genes in heterocystous cyanobacteria. Analyses support the monophyly of the Cyanobacteria, alphabetagamma-Proteobacteria, and Actinobacteria (Frankia) and provide strong support for the placement of Frankia nif genes at the base of combined the Cyanobacteria/Proteobacteria clades.

  13. Temperature- and Relative Humidity-Dependent Life History Traits of Phenacoccus solenopsis (Hemiptera: Pseudococcidae) on Hibiscus rosa-sinensis (Malvales: Malvaceae).

    PubMed

    Chen, H S; Yang, L; Huang, L F; Wang, W L; Hu, Y; Jiang, J J; Zhou, Z S

    2015-08-01

    Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), a worldwide distributive invasive pest, originated from the United States, and it was first reported in Guangdong province, China, in 2008. The effects of temperature and relative humidity (RH) on the life history traits of P. solenopsis on Hibiscus rosa-sinensis L. (Malvales: Malvaceae) were studied at seven constant temperatures (15, 20, 25, 27.5, 30, 32.5, and 35°C) and three RHs (45, 60, and 75%). The results showed that temperature, RH, and their interactions significantly influenced the life history traits of P. solenopsis. First instar was the most sensitive stage to extreme temperatures with very low survival rates at 15 and 35°C. At 25-32.5°C and the three RHs, the developmental periods of entire immature stage were shorter with values between 12.5-18.6 d. The minimum threshold temperature and the effective accumulative temperature for the pest to complete one generation were 13.2°C and 393.7 degree-days, respectively. The percentage and longevity of female adults significantly differed among different treatments. It failed to complete development at 15 or 35°C and the three RHs. Female fecundity reached the maximum value at 27.5°C and 45% RH. The intrinsic rate for increase (r), the net reproductive rate (R0), and the finite rate of increase (λ) reached the maximum values at 27.5°C and 45% RH (0.22 d(-1), 244.6 hatched eggs, and 1.25 d(-1), respectively). Therefore, we conclude that 27.5°C and 45% RH are the optimum conditions for the population development of the pest.

  14. Lifetime history of traumatic events in a young adult Mexican American sample: Relation to substance dependence, affective disorder, acculturation stress, and PTSD.

    PubMed

    Ehlers, Cindy L; Kim, Corinne; Gilder, David A; Stouffer, Gina M; Caetano, Raul; Yehuda, Rachel

    2016-12-01

    Mexican Americans comprise one of the most rapidly growing populations in the United States, and within this population, trauma and post-traumatic stress disorder (PTSD) are associated with physical and mental health problems. Therefore, efforts to delineate factors that may uniquely contribute to increased likelihood of trauma, PTSD, and substance use disorders over the lifetime in Mexican Americans are important to address health disparities and to develop treatment and prevention programs. Six hundred fourteen young adults (age 18-30 yrs) of Mexican American heritage, largely second generation, were recruited from the community and assessed with the Semi-Structured Assessment for the Genetics of Alcoholism and an acculturation stress scale. More males (51.2%) reported experiencing traumas than females (41.1%), however, a larger proportion of females received a PTSD diagnosis (15%) than males (8%). Alcohol dependence and affective disorders, but not anxiety disorders, antisocial disorders, nicotine, marijuana, or stimulant dependence, were significantly comorbid with PTSD. Endorsing higher levels of acculturation stress was also significantly associated with both trauma exposure and a diagnosis of PTSD. Logistic regression revealed that female gender, having an affective disorder, alcohol dependence, higher levels of acculturation stress, and lower levels of education were all predictors of PTSD status. Additionally, alcohol dependence generally occurred after the PTSD diagnosis in early adulthood in this high-risk population. These studies suggest that treatment and prevention efforts should particularly focus on young adult second generation Mexican American women with higher levels of acculturation stress, who may be at higher risk for PTSD, affective disorder, and alcohol dependence following trauma exposure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Truncation and reset process on the dynamics of Parrondo's games

    NASA Astrophysics Data System (ADS)

    Chang, Cheng-Hung; Tsong, Tian Yow

    2003-02-01

    The counter-intuitive feature of Parrondo’s games is illustrated on various dynamical systems combined from different deterministic and stochastic subsystems. The concept of truncation and reset process is introduced, which provides a transparent perspective to understand the underlying mechanism of this class of dynamics, including the transport of flashing ratchets, and clarifies the puzzlement why random switching between two games can generate reversal dynamics as periodical switching does.

  16. Entangled histories

    NASA Astrophysics Data System (ADS)

    Cotler, Jordan; Wilczek, Frank

    2016-12-01

    We introduce quantum history states and their mathematical framework, thereby reinterpreting and extending the consistent histories approach to quantum theory. Through thought experiments, we demonstrate that our formalism allows us to analyze a quantum version of history in which we reconstruct the past by observations. In particular, we can pass from measurements to inferences about ‘what happened’ in a way that is sensible and free of paradox. Our framework allows for a richer understanding of the temporal structure of quantum theory, and we construct history states that embody peculiar, non-classical correlations in time.

  17. Annual life-history dependent seasonal differences in neural activity of the olfactory system between non-migratory and migratory songbirds.

    PubMed

    Rastogi, Ashutosh; Surbhi; Malik, Shalie; Rani, Sangeeta; Kumar, Vinod

    2016-01-01

    Present study investigated seasonal plasticity in neural activity of the olfactory system, and assessed whether this was influenced by differences in seasonal life-history states (LHSs) between the non-migratory and migratory birds. Brains of non-migratory Indian weaver birds and migratory redheaded buntings were processed for ZENK immunohistochemistry, a marker of neuronal activation, at the times of equinoxes (March, September) and solstices (June, December), which correspond with the periods of different seasonal LHSs during the year. Immunoreactivity was quantified in brain regions comprising the olfactory system viz. olfactory bulb (OB), anterior olfactory nucleus (AON), prepiriform cortex (CPP), lateral olfactory tract (LOT) and olfactory cortex (piriform cortex, CPI; lateral olfactory cortex, LOC). In weaver birds, ZENK-like immunoreactive (ZENK-lir) cells were significantly higher in all the brain areas during post-breeding season (September) than during the other seasons; OBs had higher neuronal activity in the breeding season (June), however. A similar neural activity pattern but at enhanced levels was found in migratory buntings almost all the year. These results for the first time show LHS-associated differences in the seasonal plasticity of a sensory system between the non-migratory and migratory songbirds.

  18. Canadian History.

    ERIC Educational Resources Information Center

    School Libraries in Canada, 2003

    2003-01-01

    Includes 22 articles that address Canadian history and the importance of having students honor Canada's past by providing articles relating to the areas of History and Social Studies covering: historical fiction as instructional material; Canadian scientists; agricultural fairs; the Historical Foundation; social science books on Canada; student…

  19. Risk Factors for Relapse and Higher Costs among Medicaid Members with Opioid Dependence or Abuse: Opioid Agonists, Comorbidities, and Treatment History

    PubMed Central

    Clark, Robin E.; Baxter, Jeffrey D.; Aweh, Gideon; O'Connell, Elizabeth; Fisher, William H.; Barton, Bruce A.

    2015-01-01

    Clinical trials show that opioid agonist therapy (OAT) with methadone or buprenorphine is more effective than behavioral treatments, but state policymakers remain ambivalent about covering OAT for long periods. We used Medicaid claims for 52,278 Massachusetts Medicaid beneficiaries with a diagnosis of opioid abuse or dependence between 2004 and 2010 to study associations between use of methadone, buprenorphine or other behavioral health treatment without OAT, and time to relapse and total healthcare expenditures. Cox Proportional Hazards ratios for patients treated with either methadone or buprenorphine showed approximately 50% lower risk of relapse than behavioral treatment without OAT. Expenditures per month were from $153 to $233 lower for OAT episodes compared to other behavioral treatment. Co-occurring alcohol abuse/dependence quadrupled the risk of relapse, other non-opioid abuse/dependence doubled the relapse risk and severe mental illness added 80% greater risk compared to those without each of those disorders. Longer current treatment episodes were associated with lower risk of relapse. Relapse risk increased as prior treatment exposure increased but prior treatment was associated with slightly lower total healthcare expenditures. These findings suggest that the effectiveness of OAT that has been demonstrated in clinical trials persists at the population level in a less controlled setting and that OAT is associated with lower total healthcare expenditures compared to other forms of behavioral treatment for patients with opioid addiction. Co-occurring other substance use and mental illness exert strong influences on cost and risk of relapse, suggesting that individuals with these conditions need more comprehensive treatment. PMID:25997674

  20. Risk Factors for Relapse and Higher Costs Among Medicaid Members with Opioid Dependence or Abuse: Opioid Agonists, Comorbidities, and Treatment History.

    PubMed

    Clark, Robin E; Baxter, Jeffrey D; Aweh, Gideon; O'Connell, Elizabeth; Fisher, William H; Barton, Bruce A

    2015-10-01

    Clinical trials show that opioid agonist therapy (OAT) with methadone or buprenorphine is more effective than behavioral treatments, but state policymakers remain ambivalent about covering OAT for long periods. We used Medicaid claims for 52,278 Massachusetts Medicaid beneficiaries with a diagnosis of opioid abuse or dependence between 2004 and 2010 to study associations between use of methadone, buprenorphine or other behavioral health treatment without OAT, and time to relapse and total healthcare expenditures. Cox Proportional Hazards ratios for patients treated with either methadone or buprenorphine showed approximately 50% lower risk of relapse than behavioral treatment without OAT. Expenditures per month were from $153 to $233 lower for OAT episodes compared to other behavioral treatment. Co-occurring alcohol abuse/dependence quadrupled the risk of relapse, other non-opioid abuse/dependence doubled the relapse risk and severe mental illness added 80% greater risk compared to those without each of those disorders. Longer current treatment episodes were associated with lower risk of relapse. Relapse risk increased as prior treatment exposure increased but prior treatment was associated with slightly lower total healthcare expenditures. These findings suggest that the effectiveness of OAT that has been demonstrated in clinical trials persists at the population level in a less controlled setting and that OAT is associated with lower total healthcare expenditures compared to other forms of behavioral treatment for patients with opioid addiction. Co-occurring other substance use and mental illness exert strong influences on cost and risk of relapse, suggesting that individuals with these conditions need more comprehensive treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Corticotropin-releasing Factor in the Rat Dorsal Raphe Nucleus Promotes Different Forms of Behavioral Flexibility Depending on Social Stress History

    PubMed Central

    Snyder, Kevin P; Hill-Smith, Tiffany E; Lucki, Irwin; Valentino, Rita J

    2015-01-01

    The stress-related neuropeptide, corticotropin-releasing factor (CRF) regulates the dorsal raphe nucleus–serotonin (DRN–5-HT) system during stress and this may underlie affective and cognitive dysfunctions that characterize stress-related psychiatric disorders. CRF acts on both CRF1 and CRF2 receptor subtypes in the DRN that exert opposing inhibitory and excitatory effects on DRN-5-HT neuronal activity and 5-HT forebrain release, respectively. The current study first assessed the cognitive effects of intra-DRN microinfusion of CRF or the selective CRF2 agonist, urocortin II in stress-naive rats on performance of an operant strategy set-shifting task that is mediated by the medial prefrontal cortex (mPFC). CRF (30 ng) facilitated strategy set-shifting performance, whereas higher doses of CRF and urocortin II that would interact with CRF2 were without effect, consistent with a CRF1-mediated action. This dose decreased 5-HT extracellular levels in the mPFC, further supporting a role for CRF1. The effects of CRF were then assessed in rats exposed to repeated social stress using the resident–intruder model. Repeated social stress shifted the CRF effect from facilitation of strategy set shifting to facilitation of reversal learning and this was most prominent in a subpopulation of rats that resist defeat. Notably, in this subpopulation of rats 5-HT neuronal responses to CRF have been demonstrated to shift from CRF1-mediated inhibition to CRF2-mediated excitation. Because 5-HT facilitates reversal learning, the present results suggest that stress-induced changes in the cellular effects of CRF in the DRN translate to changes in cognitive effects of CRF. Together, the results underscore the potential for stress history to shift cognitive processing through changes in CRF neurotransmission in the DRN and the association of this effect with coping strategy. PMID:25865931

  2. Temporal variation in life-history traits of the clam Tivela mactroides (Bivalvia: Veneridae): Density-dependent processes in sandy beaches

    NASA Astrophysics Data System (ADS)

    Turra, Alexander; Petracco, Marcelo; Amaral, A. Cecilia Z.; Denadai, Márcia R.

    2014-10-01

    Temporal variation in the structure and dynamics of a population of Tivela mactroides was examined over two periods (2003-2004 and 2007-2008) in the southern part of Caraguatatuba Bay, southeastern Brazil. During the first period from January 2003 to October 2004, sampling was conducted monthly. Sampling in the second period was performed in the summer (January and February 2007 and 2008) and winter (July and August 2007 and 2008). The von Bertalanffy growth function was applied to estimate growth parameters for both periods from length-frequency distributions. Production was determined using the mass-specific growth rate method. Results indicated that the mean abundance (±SE) of T. mactroides varied sharply between the two periods, with an increase of almost 150 times from 2003 to 2004 (8.67·102 ± 0.83·102 ind m-1) to 2007-2008 (1.25·105 ± 3.33·104 ind m-1). The higher abundance in the second period was related to successful recruitment events. While the mean biomass and the production were higher in the second (5.43 ± 0.87 kg AFDM m-1 and 7.89 kg AFDM m-1 yr-1) than in the first period (0.18 ± 0.02 kg AFDM m-1 and 0.18 kg AFDM m-1 yr-1), lower values of shell length, curvature parameter, asymptotic length of the VBGF, and the growth index phi-prime in 2007-2008 (17.57 ± 1.35 mm; K = 0.40 yr-1; L∞ = 38.60 mm, ϕ‧ = 2.78) than in 2003-2004 (26.21 ± 1.21 mm; K = 1.00 yr-1; L∞ = 40.75 mm, ϕ‧ = 3.22) were related to a strongly density-dependent growth process in the second period. The oscillation in growth observed in the second, but not in the first period also indicates a process of density-dependent growth. These sharp temporal variations in population parameters of T. mactroides suggest the occurrence of density-dependent processes, and reinforce the importance of these processes in structuring sandy-beach populations.

  3. A history of chronic morphine exposure during adolescence increases despair-like behaviour and strain-dependently promotes sociability in abstinent adult mice

    PubMed Central

    Lutz, PE; Reiss, D; Ouagazzal, AM; Kieffer, BL

    2013-01-01

    A crucial issue in treating opiate addiction, a chronic relapsing disorder, is to maintain a drug-free abstinent state. Prolonged abstinence associates with mood disorders, strongly contributing to relapse. In particular, substance use disorders occurring during adolescence predispose to depression later in adulthood. Using our established mouse model of opiate abstinence, we characterized emotional consequences into adulthood of morphine exposure during adolescence. Our results indicate that morphine treatment in adolescent mice has no effect on anxiety-like behaviours in adult mice, after abstinence. In contrast, morphine treatment during adolescence increases behavioural despair in adult mice. We also show that morphine exposure strain-dependently enhances sociability in adult mice. Additional research will be required to understand where and how morphine acts during brain maturation to affect emotional and social behaviours into adulthood. PMID:23295400

  4. A history of chronic morphine exposure during adolescence increases despair-like behaviour and strain-dependently promotes sociability in abstinent adult mice.

    PubMed

    Lutz, P E; Reiss, D; Ouagazzal, A M; Kieffer, B L

    2013-04-15

    A crucial issue in treating opiate addiction, a chronic relapsing disorder, is to maintain a drug-free abstinent state. Prolonged abstinence associates with mood disorders, strongly contributing to relapse. In particular, substance use disorders occurring during adolescence predispose to depression later in adulthood. Using our established mouse model of opiate abstinence, we characterized emotional consequences into adulthood of morphine exposure during adolescence. Our results indicate that morphine treatment in adolescent mice has no effect on anxiety-like behaviours in adult mice, after abstinence. In contrast, morphine treatment during adolescence increases behavioural despair in adult mice. We also show that morphine exposure strain-dependently enhances sociability in adult mice. Additional research will be required to understand where and how morphine acts during brain maturation to affect emotional and social behaviours into adulthood. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Pleistocene evolutionary history of the Clouded Apollo (Parnassius mnemosyne): genetic signatures of climate cycles and a 'time-dependent' mitochondrial substitution rate.

    PubMed

    Gratton, P; Konopiński, M K; Sbordoni, V

    2008-10-01

    Genetic data are currently providing a large amount of new information on past distribution of species and are contributing to a new vision of Pleistocene ice ages. Nonetheless, an increasing number of studies on the 'time dependency' of mutation rates suggest that date assessments for evolutionary events of the Pleistocene might be overestimated. We analysed mitochondrial (mt) DNA (COI) sequence variation in 225 Parnassius mnemosyne individuals sampled across central and eastern Europe in order to assess (i) the existence of genetic signatures of Pleistocene climate shifts; and (ii) the timescale of demographic and evolutionary events. Our analyses reveal a phylogeographical pattern markedly influenced by the Pleistocene/Holocene climate shifts. Eastern Alpine and Balkan populations display comparatively high mtDNA diversity, suggesting multiple glacial refugia. On the other hand, three widely distributed and spatially segregated lineages occupy most of northern and eastern Europe, indicating postglacial recolonization from different refugial areas. We show that a conventional 'phylogenetic' substitution rate cannot account for the present distribution of genetic variation in this species, and we combine phylogeographical pattern and palaeoecological information in order to determine a suitable intraspecific rate through a Bayesian coalescent approach. We argue that our calibrated 'time-dependent' rate (0.096 substitutions/ million years), offers the most convincing time frame for the evolutionary events inferred from sequence data. When scaled by the new rate, estimates of divergence between Balkan and Alpine lineages point to c. 19 000 years before present (last glacial maximum), and parameters of demographic expansion for northern lineages are consistent with postglacial warming (5-11 000 years before present).

  6. Family History

    MedlinePlus

    Your family history includes health information about you and your close relatives. Families have many factors in common, including their genes, ... as heart disease, stroke, and cancer. Having a family member with a disease raises your risk, but ...

  7. Natural History of Dependency in the Elderly: A 24-Year Population-Based Study Using a Longitudinal Item Response Theory Model.

    PubMed

    Edjolo, Arlette; Proust-Lima, Cécile; Delva, Fleur; Dartigues, Jean-François; Pérès, Karine

    2016-02-15

    We aimed to describe the hierarchical structure of Instrumental Activities of Daily Living (IADL) and basic Activities of Daily Living (ADL) and trajectories of dependency before death in an elderly population using item response theory methodology. Data were obtained from a population-based French cohort study, the Personnes Agées QUID (PAQUID) Study, of persons aged ≥65 years at baseline in 1988 who were recruited from 75 randomly selected areas in Gironde and Dordogne. We evaluated IADL and ADL data collected at home every 2-3 years over a 24-year period (1988-2012) for 3,238 deceased participants (43.9% men). We used a longitudinal item response theory model to investigate the item sequence of 11 IADL and ADL combined into a single scale and functional trajectories adjusted for education, sex, and age at death. The findings confirmed the earliest losses in IADL (shopping, transporting, finances) at the partial limitation level, and then an overlapping of concomitant IADL and ADL, with bathing and dressing being the earliest ADL losses, and finally total losses for toileting, continence, eating, and transferring. Functional trajectories were sex-specific, with a benefit of high education that persisted until death in men but was only transient in women. An in-depth understanding of this sequence provides an early warning of functional decline for better adaptation of medical and social care in the elderly.

  8. The way to her heart? Response to romantic cues is dependent on hunger state and dieting history: An fMRI pilot study.

    PubMed

    Ely, Alice V; Childress, Anna Rose; Jagannathan, Kanchana; Lowe, Michael R

    2015-12-01

    Normal weight historical dieters (HDs) are prone to future weight gain, and show higher levels of brain activation in reward-related regions after having eaten than nondieters (NDs) in response to food stimuli (Ely, Childress, Jagannathan, & Lowe, 2014), a similar pattern to that seen in obesity. We hypothesized that HDs are differentially sensitive after eating to rewards in general, and thus extended prior findings by comparing the same groups' brain activation when viewing romantic pictures compared to neutral stimuli while being scanned in a blood oxygenation level-dependent (BOLD) fMRI paradigm in a fasted and fed state. Results show that 1) in fed relative to fasted conditions, both HDs and NDs were more responsive in areas related to reward and 2) in HDs, greater fed versus fasted activation extended to areas linked to perception and goal-directed behavior. HDs relative to NDs were more responsive to romantic cues in the superior frontal gyrus when fasted and the middle temporal gyrus when fed. This pattern of response is similar to HDs' activation when viewing highly palatable food cues, and is consistent with research showing overlapping brain-based responses to sex, drugs and food.

  9. Molecular evolutionary history of Sugarcane yellow leaf virus based on sequence analysis of RNA-dependent RNA polymerase and putative aphid transmission factor-coding genes.

    PubMed

    ElSayed, Abdelaleim Ismail; Boulila, Moncef; Rott, Philippe

    2014-06-01

    RNA-dependent RNA polymerase (RdRp) encoded by ORF2 and putative aphid transmission factor (PATF) encoded by ORF5 of Sugarcane yellow leaf virus (SCYLV) were detected in six sugarcane cultivars affected by yellow leaf using RT-PCR and real-time RT-PCR assays. Expression of both genes varied among infected plants, but overall expression of RdRp was higher than expression of PATF. Cultivar H87-4094 from Hawaii yielded the highest transcript levels of RdRp, whereas cultivar C1051-73 from Cuba exhibited the lowest levels. Sequence comparisons among 25 SCYLV isolates from various geographical locations revealed an amino acid similarity of 72.1-99.4 and 84.7-99.8 % for the RdRp and PATF genes, respectively. The 25 SCYLV isolates were separated into three (RdRp) and two (PATF) phylogenetic groups using the MEGA6 program that does not account for genetic recombination. However, the SCYLV genome contained potential recombination signals in the RdRp and PATF coding genes based on the GARD genetic algorithm. Use of this later program resulted in the reconstruction of phylogenies on the left as well as on the right sides of the putative recombination breaking points, and the 25 SCYLV isolates were distributed into three distinct phylogenetic groups based on either RdRp or PATF sequences. As a result, recombination reshuffled the affiliation of the accessions to the different clusters. Analysis of selection pressures exerted on RdRp and PATF encoded proteins revealed that ORF 2 and ORF 5 underwent predominantly purifying selection. However, a few sites were also under positive selection as assessed by various models such as FEL, IFEL, REL, FUBAR, MEME, GA-Branch, and PRIME.

  10. Introducing Labor History.

    ERIC Educational Resources Information Center

    Whitmer, John Dale

    1997-01-01

    Provides a brief overview for including labor history in the social studies curriculum. Notes the broad range of subjects (geography, history, economics, music, and art) and approaches (women's history, social history, oral history) that encompass labor history. (MJP)

  11. Lunar History

    NASA Technical Reports Server (NTRS)

    Edmunson, Jennifer E.

    2009-01-01

    This section of the workshop describes the history of the moon, and offers explanations for the importance of understanding lunar history for engineers and users of lunar simulants. Included are summaries of the initial impact that is currently in favor as explaining the moon's formation, the crust generation, the creation of craters by impactors, the era of the lunar cataclysm, which some believe effected the evolution of life on earth, the nature of lunar impacts, crater morphology, which includes pictures of lunar craters that show the different types of craters, more recent events include effect of micrometeorites, solar wind, radiation and generation of agglutinates. Also included is a glossary of terms.

  12. Bulletproof History.

    ERIC Educational Resources Information Center

    Roy, R. H.

    1994-01-01

    Asserts that the writers and producers of the television documentary, "The Valour and the Horror," provided a false impression of an event to fit preconceived and erroneous interpretations of history. Points out specific examples of inaccurate historical presentations and provides contradictory historical interpretations. (CFR)

  13. Arguing History

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2013-01-01

    The history of science illustrates some exciting--and sometimes controversial--moments. Unfortunately, textbooks tend to focus on results in a scientific discipline and only occasionally showcase an interesting historical vignette, telling the story behind those results. Although required studies may leave teachers little classroom time for…

  14. Making History

    ERIC Educational Resources Information Center

    Shein, Esther

    2008-01-01

    Jennifer Dorman was in a fix. Teaching ninth-grade US history at Holicong Middle School in Doylestown, Pennsylvania, Dorman wanted to tap into her students' interest in creating "something of value not just for their teachers, but something they could share with other students and people." But that required something a conventional paper-based…

  15. Humanistic History.

    ERIC Educational Resources Information Center

    Marrow, Alvin J.

    1982-01-01

    Utilizing the theories of McGregor, Maslow, and Herzberg, presents a model for teaching history which involves students in designing their own course objectives. Includes humanistic approaches, organizational management assumptions, and models with motivational, hygiene, physiological, and safety factors. (DMM)

  16. Making History

    ERIC Educational Resources Information Center

    Shein, Esther

    2008-01-01

    Jennifer Dorman was in a fix. Teaching ninth-grade US history at Holicong Middle School in Doylestown, Pennsylvania, Dorman wanted to tap into her students' interest in creating "something of value not just for their teachers, but something they could share with other students and people." But that required something a conventional paper-based…

  17. Bulletproof History.

    ERIC Educational Resources Information Center

    Roy, R. H.

    1994-01-01

    Asserts that the writers and producers of the television documentary, "The Valour and the Horror," provided a false impression of an event to fit preconceived and erroneous interpretations of history. Points out specific examples of inaccurate historical presentations and provides contradictory historical interpretations. (CFR)

  18. Arguing History

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2013-01-01

    The history of science illustrates some exciting--and sometimes controversial--moments. Unfortunately, textbooks tend to focus on results in a scientific discipline and only occasionally showcase an interesting historical vignette, telling the story behind those results. Although required studies may leave teachers little classroom time for…

  19. History dependence of magnetomechanical properties of steel

    NASA Astrophysics Data System (ADS)

    Melquiond, F.; Mouroux, A.; Jouglar, J.; Vuillermoz, P. L.; Weinstock, H.

    1996-05-01

    Magnetomechanical measurements using a superconducting SQUID magnetic gradiometer and a tensile-testing machine have been performed on a variety of steel specimens to determine the change in magnetization due to applied stress and the possible application of the observed behavior as a new form of nondestructive evaluation in steel. This study builds on earlier related measurements.

  20. River history.

    PubMed

    Vita-Finzi, Claudio

    2012-05-13

    During the last half century, advances in geomorphology-abetted by conceptual and technical developments in geophysics, geochemistry, remote sensing, geodesy, computing and ecology-have enhanced the potential value of fluvial history for reconstructing erosional and depositional sequences on the Earth and on Mars and for evaluating climatic and tectonic changes, the impact of fluvial processes on human settlement and health, and the problems faced in managing unstable fluvial systems. This journal is © 2012 The Royal Society

  1. Uncovering History for Future History Teachers

    ERIC Educational Resources Information Center

    Fischer, Fritz

    2010-01-01

    The art of history teaching is at a crossroads. Recent scholarship focuses on the need to change the teaching of history so students can better learn history, and insists that history teachers must move beyond traditional structures and methods of teaching in order to improve their students' abilities to think with history. This article presents…

  2. Uncovering History for Future History Teachers

    ERIC Educational Resources Information Center

    Fischer, Fritz

    2010-01-01

    The art of history teaching is at a crossroads. Recent scholarship focuses on the need to change the teaching of history so students can better learn history, and insists that history teachers must move beyond traditional structures and methods of teaching in order to improve their students' abilities to think with history. This article presents…

  3. Cygnus History

    SciTech Connect

    David J. Henderson, Raymond E. Gignac, Douglas E. Good, Mark D. Hansen, Charles V. Mitton; Daniel S. Nelson, Eugene C. Ormond; Steve R. Cordova, Isidro Molina; John R. Smith, Evan A. Rose

    2009-07-02

    The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources: Cygnus 1 and Cygnus 2. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site. The sources were developed to produce high-resolution images for dynamic plutonium experiments. This work will recount and discuss salient maintenance and operational issues encountered during the history of Cygnus. A brief description of Cygnus systems and rational for design selections will set the stage for this historical narrative. It is intended to highlight the team-derived solutions for technical problems encountered during extended periods of maintenance and operation. While many of the issues are typical to pulsed power systems, some of the solutions are unique. It is hoped that other source teams will benefit from this presentation, as well as other necessary disciplines (e.g., source users, system architects, facility designers and managers, funding managers, and team leaders).

  4. Glaucoma history and risk factors.

    PubMed

    McMonnies, Charles W

    Apart from the risk of developing glaucoma there is also the risk that it is not detected and irreversible loss of vision ensues. Some studies of methods of glaucoma diagnosis have examined the results of instrument-based examinations with great if not complete reliance on objective findings in arriving at a diagnosis. The very valuable advances in glaucoma detection instrument technologies, and apparent increasing dependence on them, may have led to reduced consideration of information available from a patient history in those studies. Dependence on objective evidence of glaucomatous pathology may reduce the possibility of detecting glaucoma suspects or patients at risk for becoming glaucoma suspects. A valid positive family history of glaucoma is very valuable information. However, negative family histories can often be unreliable due to large numbers of glaucoma cases being undiagnosed. No evidence of family history is appropriate rather than no family history. In addition the unreliability of a negative family history is increased when patients with glaucoma fail to inform their family members. A finding of no family history can only be stated as no known family history. In examining the potential diagnostic contribution from a patient history, this review considers, age, frailty, race, type and degree of refractive error, systemic hyper- and hypotension, vasospasm, migraine, pigmentary dispersion syndrome, pseudoexfoliation syndrome, obstructive sleep apnea syndrome, diabetes, medication interactions and side effects, the degree of exposure to intraocular and intracranial pressure elevations and fluctuations, smoking, and symptoms in addition to genetics and family history of the disease. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  5. The Future of History and History Teaching.

    ERIC Educational Resources Information Center

    Commager, Henry Steele

    1983-01-01

    Technical history, a quantitative record of history strengthened by new techniques in mathematics, computer science, and other fields has advantages over former approaches to history--history as philosophy and historical theology. For example, it makes available more source materials. However, it has drawbacks, e.g., it directs research to highly…

  6. The Future of History and History Teaching.

    ERIC Educational Resources Information Center

    Commager, Henry Steele

    1983-01-01

    Technical history, a quantitative record of history strengthened by new techniques in mathematics, computer science, and other fields has advantages over former approaches to history--history as philosophy and historical theology. For example, it makes available more source materials. However, it has drawbacks, e.g., it directs research to highly…

  7. Ras history

    PubMed Central

    2010-01-01

    Although the roots of Ras sprouted from the rich history of retrovirus research, it was the discovery of mutationally activated RAS genes in human cancer in 1982 that stimulated an intensive research effort to understand Ras protein structure, biochemistry and biology. While the ultimate goal has been developing anti-Ras drugs for cancer treatment, discoveries from Ras have laid the foundation for three broad areas of science. First, they focused studies on the origins of cancer to the molecular level, with the subsequent discovery of genes mutated in cancer that now number in the thousands. Second, elucidation of the biochemical mechanisms by which Ras facilitates signal transduction established many of our fundamental concepts of how a normal cell orchestrates responses to extracellular cues. Third, Ras proteins are also founding members of a large superfamily of small GTPases that regulate all key cellular processes and established the versatile role of small GTP-binding proteins in biology. We highlight some of the key findings of the last 28 years. PMID:21686117

  8. Dependent Probability Spaces

    ERIC Educational Resources Information Center

    Edwards, William F.; Shiflett, Ray C.; Shultz, Harris

    2008-01-01

    The mathematical model used to describe independence between two events in probability has a non-intuitive consequence called dependent spaces. The paper begins with a very brief history of the development of probability, then defines dependent spaces, and reviews what is known about finite spaces with uniform probability. The study of finite…

  9. The Rhetorical Force of History in Public Argument.

    ERIC Educational Resources Information Center

    Schwartzman, Roy

    The rhetorical functions of history depend on the domain in which history is used, with no connotations of interpretive priority attaching to the social or the academic realm. The appropriation of history in support of social causes as radically opposed as socialism and fascism fuels the temptation to subsume history under ideology, with the…

  10. KSC History Project

    NASA Technical Reports Server (NTRS)

    Dethloff, Henry C.

    2001-01-01

    The KSC History Project focuses on archival research and oral history interviews on the history of Kennedy Space Center (KSC). Related projects include the preparation of a precis and chapter outline for a proposed book-length narrative history, a bibliography of key primary and secondary resources, a brief monograph overview of the history of KSC, and a monograph on the history of safety at the Center. Finally, there is work on the development of a web page and a personal history data base associated with the oral history project. The KSC History Project has been a joint endeavor between Henry C. Dethloff and Dr. Noble Lee Snaples, Jr.

  11. Celebrate Women's History.

    ERIC Educational Resources Information Center

    Leonard, Carolyn M.; Baradar, Mariam

    This teachers' guide to activities celebrating Women's History Month focuses on women whose important contributions have been omitted from history textbooks. Women's History Month grew from a 1977 celebration of Women's History Week and is intended to bring women's history into the school curriculum. International Women's Day, celebrated on March…

  12. History of Geology.

    ERIC Educational Resources Information Center

    Greene, Mott T.

    1985-01-01

    Discusses: (1) geologists and the history of geology; (2) American historians and the history of geology; (3) history of geology in the 1980s; (4) sources for the history of geology (bibliographies, dictionaries, encyclopedias, handbooks, periodicals, public/official histories, compilations, and books); (5) research opportunities; and (6) other…

  13. History and Multimedia Technology. Media Corner.

    ERIC Educational Resources Information Center

    Mitchell-Powell, Brenda, Ed.

    1994-01-01

    Contends that, although multimedia technology offers new options for history instruction, its value depends on the consistency, reliability, and convenience of operational methods. Provides reviews of three recommended and one not recommended multimedia packages. (CFR)

  14. Let History Reign

    ERIC Educational Resources Information Center

    Manzo, Kathleen Kennedy

    2008-01-01

    Spanish River High School is one of 40 U.S. History Schools and 21 affiliates around the country that get resources and academic support from the Gilder Lehrman Institute of American History. The schools require participating students to take a U.S. history course each year, in addition to any requisites in world history and other subjects. The…

  15. What Is Literary "History"?

    ERIC Educational Resources Information Center

    Harris, Wendell V.

    1994-01-01

    Examines the meaning of the word "history" as used in the common phrase "literary history" by critics and scholars. Asserts the differences between historical scholarship and literary history. Argues that the grounding activity of literary history is insulated from the relativism insisted upon by poststructuralist theorizing.…

  16. Integrating Women's History and Regular History.

    ERIC Educational Resources Information Center

    Filene, Peter G.

    1980-01-01

    Describes a university course which synthesizes women's history with traditional history. The four-part curricular sequence comprises the socioeconomic situation; occupations, including housework and how and whether women were employed; values, ideas, and images; and politics, including movements such as suffragism, birth control, and temperance.…

  17. Family Health History and Diabetes

    MedlinePlus

    ... Risk Test Family Health History Quiz Family Health History Quiz Family health history is an important risk ... Should Ask Your Family About Diabetes & Family Health History Knowing your family health history is important. Here ...

  18. Visual dependence and BPPV.

    PubMed

    Agarwal, K; Bronstein, A M; Faldon, M E; Mandalà, M; Murray, K; Silove, Y

    2012-06-01

    The increased visual dependence noted in some vestibular patients may be secondary to their vertigo. We examine whether a single, brief vertigo attack, such as in benign paroxysmal positional vertigo (BPPV), modifies visual dependency. Visual dependency was measured before and after the Hallpike manoeuvre with (a) the Rod and Frame and the Rod and Disc techniques whilst seated and (b) the postural sway induced by visual roll-motion stimulation. Three subject groups were studied: 20 patients with BPPV (history and positive Hallpike manoeuvre; PosH group), 20 control patients (history of BPPV but negative Hallpike manoeuvre; NegH group) and 20 normal controls. Our findings show that while both patient groups showed enhanced visual dependency, the PosH and the normal control group decreased visual dependency on repetition of the visual tasks after the Hallpike manoeuvre. NegH patients differed from PosH patients in that their high visual dependency did not diminish on repetition of the visual stimuli; they scored higher on the situational characteristic questionnaire ('visual vertigo' symptoms) and showed higher incidence of migraine. We conclude that long term vestibular symptoms increase visual dependence but a single BPPV attack does not increase it further. Repetitive visual motion stimulation induces adaptation in visual dependence in peripheral vestibular disorders such as BPPV. A positional form of vestibular migraine may underlie the symptoms of some patients with a history of BPPV but negative Hallpike manoeuvre. The finding that they have non adaptable increased visual dependency may explain visuo-vestibular symptoms in this group and, perhaps more widely, in patients with migraine.

  19. KSC History Project

    NASA Technical Reports Server (NTRS)

    Snaples, Lee

    2001-01-01

    The project is a joint endeavor between Dr. Henry Dethloff and myself and is producing a number of products related to KSC history. This report is a summary of those projects. First, there is an overview monograph covering KSC history. Second, there is a chapter outline for an eventual book-length history. Third, there is monograph on safety at KSC. Finally, there is a web page and database dedicated to the KSC oral history project.

  20. An Hour in History

    NASA Image and Video Library

    2011-03-22

    John C. Stennis Space Center historian Marco Giardino speaks to center employees during the first An Hour in History session March 22. The Stennis History Office launched the series as part of the rocket engine test facility's yearlong 50th anniversary celebration. The inaugural session focused on Stennis history during the early 1960s. Subsequent sessions will focus on other aspects of Stennis history as part of the '50 Years of Powering Dreams' anniversary theme.

  1. Life-history data.

    PubMed

    Vanhoutte, Bram; Nazroo, James

    2016-07-15

    Life-history data are quantitative, retrospective and autobiographical data collected through event-history calendars. By mimicking the structure of our memories, these instruments can gather reliable information on different dimensions of the lifecourse. Life-history data enable the duration, timing and ordering of events to be brought to the foreground of analysis. Extending the scope of lifecourse research, life-history data make it possible to examine the long-term effects of past policies with more precision and detail.

  2. HAD Oral History Project

    NASA Astrophysics Data System (ADS)

    Holbrook, Jarita

    2014-01-01

    The Historical Astronomy Division is the recipient of an American Institute of Physics Neils Bohr Library Grant for Oral History. HAD has assembled a team of volunteers to conduct oral history interviews since May 2013. Each oral history interview varies in length between two and six hours. This presentation is an introduction to the HAD Oral History Project and the activities of the team during the first six months of the grant.

  3. Who Owns History?

    ERIC Educational Resources Information Center

    Hackney, Sheldon

    1995-01-01

    Presents an interview with historian Cary Carson of the Colonial Williamsburg Foundation and author William Styron on the role of history in society. Outlines the once-proposed Disney history theme park near Mannassas, Virginia. Discusses historical interpretation, museums, historical sites, and popular history. (CFR)

  4. Film and History.

    ERIC Educational Resources Information Center

    Schaber, Robin L.

    2002-01-01

    Provides an annotated bibliography of Web sites that focus on using film to teach history. Includes Web sites in five areas: (1) film and education; (2) history of cinema; (3) film and history resources; (4) film and women; and (5) film organizations. (CMK)

  5. Who Owns History?

    ERIC Educational Resources Information Center

    Hackney, Sheldon

    1995-01-01

    Presents an interview with historian Cary Carson of the Colonial Williamsburg Foundation and author William Styron on the role of history in society. Outlines the once-proposed Disney history theme park near Mannassas, Virginia. Discusses historical interpretation, museums, historical sites, and popular history. (CFR)

  6. Studying Ancient History.

    ERIC Educational Resources Information Center

    Barrow, Robin

    1982-01-01

    Defends the value and relevance of the study of ancient history and classics in history curricula. The unique homogeneity of the classical period contributes to its instructional manageability. A year-long, secondary-level course on fifth-century Greece and Rome is described to illustrate effective approaches to teaching ancient history. (AM)

  7. Conducting the Medical History

    ERIC Educational Resources Information Center

    Finkel, Martin A.; Alexander, Randell A.

    2011-01-01

    A key portion of the medical evaluation of child sexual abuse is the medical history. This differs from interviews or histories obtained by other professionals in that it is focuses more on the health and well-being of the child. Careful questions should be asked about all aspects of the child's medical history by a skilled, compassionate,…

  8. Studying Ancient History.

    ERIC Educational Resources Information Center

    Barrow, Robin

    1982-01-01

    Defends the value and relevance of the study of ancient history and classics in history curricula. The unique homogeneity of the classical period contributes to its instructional manageability. A year-long, secondary-level course on fifth-century Greece and Rome is described to illustrate effective approaches to teaching ancient history. (AM)

  9. History of Physics.

    ERIC Educational Resources Information Center

    Moyer, Albert E.

    1985-01-01

    Discusses the history of American physics, indicating that much effort has been on the atomic bond and high-energy physics, to the detriment of other topics and areas. To offset this tendency, significant research is going on in the history of solid-state physics, with glimmerings in the history of physics education. (JN)

  10. Teaching History Today.

    ERIC Educational Resources Information Center

    Bausum, Henry S., Ed.

    The 14 articles included in this collection touch on several aspects of the teaching of history. The articles are: (1) "Observations on University Teaching and Research" (N. Graebner); (2) "Teaching History: A Changing Clientele and an Affirmation of Goals" (E. Burns); (3) "History for Citizens" (W. McNeill); (4)…

  11. Film and History.

    ERIC Educational Resources Information Center

    Schaber, Robin L.

    2002-01-01

    Provides an annotated bibliography of Web sites that focus on using film to teach history. Includes Web sites in five areas: (1) film and education; (2) history of cinema; (3) film and history resources; (4) film and women; and (5) film organizations. (CMK)

  12. Parallels in History.

    ERIC Educational Resources Information Center

    Mugleston, William F.

    2000-01-01

    Believes that by focusing on the recurrent situations and problems, or parallels, throughout history, students will understand the relevance of history to their own times and lives. Provides suggestions for parallels in history that may be introduced within lectures or as a means to class discussions. (CMK)

  13. Diet History Questionnaire: Database Revision History

    Cancer.gov

    The following details all additions and revisions made to the DHQ nutrient and food database. This revision history is provided as a reference for investigators who may have performed analyses with a previous release of the database.

  14. History of Science and History of Philologies.

    PubMed

    Daston, Lorraine; Most, Glenn W

    2015-06-01

    While both the sciences and the humanities, as currently defined, may be too heterogeneous to be encompassed within a unified historical framework, there is good reason to believe that the history of science and the history of philologies both have much to gain by joining forces. This collaboration has already yielded striking results in the case of the history of science and humanist learning in early modern Europe. This essay argues that first, philology and at least some of the sciences (e.g., astronomy) remained intertwined in consequential ways well into the modern period in Western cultures; and second, widening the scope of inquiry to include other philological traditions in non-Western cultures offers rich possibilities for a comparative history of learned practices. The focus on practices is key; by shifting the emphasis from what is studied to how it is studied, deep commonalities emerge among disciplines--and intellectual traditions--now classified as disparate.

  15. Compulsivity in opioid dependence.

    PubMed

    Tolomeo, Serenella; Matthews, Keith; Steele, Douglas; Baldacchino, Alex

    2017-09-14

    This study aimed to investigate the relationship between compulsivity versus impulsivity and structural MRI abnormalities in opioid dependence. We recruited 146 participants: i) patients with a history of opioid dependence due to chronic heroin use (n=24), ii) heroin users stabilised on methadone maintenance treatment (n=48), iii) abstinent participants with a history of opioid dependence due to heroin use (n=24) and iv) healthy controls (n=50). Compulsivity was measured using Intra/Extra-Dimensional (IED) Task and impulsivity was measured using the Cambridge Gambling Task (CGT). Structural Magnetic Resonance Imaging (MRI) data were also obtained. As hypothesised, compulsivity was negatively associated with impulsivity (p<0.02). Testing for the neural substrates of compulsivity versus impulsivity, we found a higher compulsivity/impulsivity ratio associated with significantly decreased white matter adjacent to the nucleus accumbens, bed nucleus of stria terminalis and rostral cingulate in the abstinent group, compared to the other opioid dependent groups. In addition, self-reported duration of opioid exposure correlated negatively with bilateral globus pallidus grey matter reductions. Our findings are consistent with Volkow & Koob's addiction models and underline the important role of compulsivity versus impulsivity in opioid dependence. Our results have implications for the treatment of opioid dependence supporting the assertion of different behavioural and biological phenotypes in the opioid dependence and abstinence syndromes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. KSC History Project

    NASA Technical Reports Server (NTRS)

    Moore, Patrick K.

    2002-01-01

    The 2002 NASA/ASEE KSC History Project focused on a series of seven history initiatives designed to acquire, preserve, and interpret the history of Kennedy Space Center. These seven projects included the co-authoring of Voices From the Cape, historical work with NASA historian Roger Launius, the completion of a series of oral histories with key KSC personnel, a monograph on Public Affairs, the development of a Historical Concept Map (CMap) for history knowledge preservation, advice on KSC history database and web interface capabilities, the development of a KSC oral history program and guidelines of training and collection, and the development of collaborative relationships between Kennedy Space Center, the University of West Florida, and the University of Central Florida.

  17. KSC History Project

    NASA Technical Reports Server (NTRS)

    Moore, Patrick K.

    2003-01-01

    The 2003 NASA/ASEE KSC History Project focused on a series of six history initiatives designed to acquire, preserve, and interpret the history of Kennedy Space Center. These six projects included the completion of Voices From the Cape, historical work co-authored with NASA historian Roger Launius, the completion of a series of oral histories with key KSC personnel, expansion of monograph on Public Affairs into two comprehensive pieces on KSC press operations and KSC visitor operations, the expansion of KSC Historical Concept Maps (Cmap) for history knowledge preservation, the expansion of the KSC oral history program through the administration of an oral history workshop for KSC-based practitioners, and the continued collaborative relationships between Kennedy Space Center, the University of West Florida, the University of Central Florida and other institutions including the University of Louisiana at Lafayette.

  18. Surfing for history: websites featuring dental history object collections.

    PubMed

    O'Dell, Shannon

    2007-01-01

    Research is a key activity for any individual interested in dental history. It should come as no surprise that the ever-evolving Internet has become a major resource for those who seek the latest information available on this (or almost any other) subject. As a curator in a dental history museum, the author frequently checks other sources that feature dental objects while cataloging and identifying newly-acquired objects or those under consideration for exhibition. "Surfing" by computer is often the author's first activity in pursuing any research task. This paper is a tour of websites written in English that include historical dental objects. At the risk of stating the obvious, the author would like to point out that the accuracy and reliability of information on websites varies widely, depending on the source. Therefore, most of the sites listed here have been developed by institutions.

  19. History of mathematics and history of science.

    PubMed

    Mann, Tony

    2011-09-01

    This essay argues that the diversity of the history of mathematics community in the United Kingdom has influenced the development of the subject and is a significant factor behind the different concerns often evident in work on the history of mathematics when compared with that of historians of science. The heterogeneous nature of the community, which includes many who are not specialist historians, and the limited opportunities for academic careers open to practitioners have had a profound effect on the discipline, leading to a focus on elite mathematics and great mathematicians. More recently, reflecting earlier developments in the history of science, an increased interest in the context and culture of the practice of mathematics has become evident.

  20. Convection and lunar thermal history

    NASA Technical Reports Server (NTRS)

    Cassen, P.; Reynolds, R. T.; Graziani, F.; Summers, A.; Mcnellis, J.; Blalock, L.

    1979-01-01

    The effects of solid interior convection on the thermal history of the moon are examined. Convective models of lunar evolution are calculated to demonstrate the influence of various viscosities, radioactive heat source distributions and initial temperature profiles and tested by means of a thermal history simulation code. Results indicate that solid convection does not necessarily produce a quasi-steady thermal balance between heat sources and surface losses. The state of the lithosphere is found to be sensitive to the efficiency of heat source redistribution, while that of the convecting interior depends primarily on rheology. Interior viscosities of 10 to the 21st to 10 to the 22nd cm/sec are obtained, along with a central temperature above 1100 C. It is suggested that mare flooding could have been the result of magma production by pressure release melting in the upwelling region of convection cells.

  1. Counting coalescent histories.

    PubMed

    Rosenberg, Noah A

    2007-04-01

    Given a species tree and a gene tree, a valid coalescent history is a list of the branches of the species tree on which coalescences in the gene tree take place. I develop a recursion for the number of valid coalescent histories that exist for an arbitrary gene tree/species tree pair, when one gene lineage is studied per species. The result is obtained by defining a concept of m-extended coalescent histories, enumerating and counting these histories, and taking the special case of m = 1. As a sum over valid coalescent histories appears in a formula for the probability that a random gene tree evolving along the branches of a fixed species tree has a specified labeled topology, the enumeration of valid coalescent histories can considerably reduce the effort required for evaluating this formula.

  2. 2011 Women's History Month

    NASA Image and Video Library

    2011-03-24

    John C. Stennis Space Center employees (l to r) Janet Kovac (NASA Shared Services Center), Lael Butler (Environmental Protection Agency Gulf of Mexico Program), Mary Carter (NSSC) and Maura Lohrenz (Naval Research Laboratory) celebrate a correct answer during the Women's History Month Quiz Bowl held onsite March 24. The contest between the women and a panel of four men tested each side's knowledge of women's history facts and events. This year's Women's History Month theme was 'Our History is Our Strength.' Befitting that sentiment, the panel of women won the contest.

  3. Teaching History: The Fax about History

    ERIC Educational Resources Information Center

    Bryant, James A., Jr.

    2005-01-01

    Social studies and history have taken a back seat to other subjects in recent years, but the author argues that there is far too much at stake to allow these important fields to become irrelevant. To drive home the point, in this article, he shares a story about the 9/11 Commission, that made headlines in 2004.

  4. Suicidal Behavior in Chemically Dependent Adolescents.

    ERIC Educational Resources Information Center

    Cavaiola, Alan A.; Lavender, Neil

    1999-01-01

    Study explores distinctions between chemically dependent suicide attempters, chemically dependent nonsuicidal adolescents, and high school students with no history of chemical dependency (N=250). Results reveal that there were significant differences between the chemically dependent groups. It was also found that the majority of suicidal gestures…

  5. Diet history: Method and applications.

    PubMed

    Morán Fagúndez, Luis Juan; Rivera Torres, Alejandra; González Sánchez, María Eugenia; de Torres Aured, Mari Lourdes; Pérez Rodrigo, Carmen; Irles Rocamora, José Antonio

    2015-02-26

    The diet history is a traditional method of analysis of food intake. In its traditional structure consists of three components that provide an overall information of the usual food consumption pattern of the individual and also detailed information on certain foods. The information is collected in an interview and requires highly experienced qualified interviewers. The quality of information depends largely on the skills of the interviewer. It is mostly used in clinical practice. It has also been used in studies of diet and health relationship to investigate the usual diet in the past. The high cost and long duration of the interview limit their usefulness in large epidemiological studies.

  6. Make History Come Alive.

    ERIC Educational Resources Information Center

    Karwoski, Gail Langer

    2003-01-01

    Suggests activities that school library media specialists can use to encourage students to think of history as fun and relevant and to want to read history books. Discusses heroism in poems and songs; writing poems based on historical figures; biographies; limericks; and publishing student writings on parchment paper. (LRW)

  7. Teaching Nuclear History.

    ERIC Educational Resources Information Center

    Holl, Jack M.; Convis, Sheila C.

    1991-01-01

    Presents results of a survey of the teaching about nuclear history at U.S. colleges and universities. Reports the existence of a well-established and extensive literature, a focus on nuclear weapons or warfare, and a concentration on nuclear citizenship, therapy, or eschatology for courses outside of history departments. Discusses individual…

  8. History and Ecological Education.

    ERIC Educational Resources Information Center

    Cherif, Abour H.

    1988-01-01

    Discusses the main objectives of ecohistory and sources of information for this study. Details five themes that are important for students to know about the history of ecology including the history of Earth, fauna and flora, the human species, human civilization, and changes in the human environment. (CW)

  9. Doing Local History.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1992-01-01

    This theme issue contains articles about the importance of learning local history. The lead article includes historical information about three Iowa cities: Council Bluffs, Waterloo, and Jefferson. Other features in this issue are entitled: "Iowa Kids Talk,""Digging Into Local History,""Goldie's Top Ten News Stories";…

  10. History Teaching in Hungary.

    ERIC Educational Resources Information Center

    Vero, Julia, Ed.

    1986-01-01

    A compilation of five documents defines and explores the role, scope, reforms, and current trends in history teaching in Hungary. Ivan Berend in "Educational Ideas and History," considers whether or not the traditional uses of historical knowledge have become obsolete and examines the value of this knowledge in today's society. Peter…

  11. Implementing Big History.

    ERIC Educational Resources Information Center

    Welter, Mark

    2000-01-01

    Contends that world history should be taught as "Big History," a view that includes all space and time beginning with the Big Bang. Discusses five "Cardinal Questions" that serve as a course structure and address the following concepts: perspectives, diversity, change and continuity, interdependence, and causes. (CMK)

  12. Microscale acceleration history discriminators

    DOEpatents

    Polosky, Marc A.; Plummer, David W.

    2002-01-01

    A new class of micromechanical acceleration history discriminators is claimed. These discriminators allow the precise differentiation of a wide range of acceleration-time histories, thereby allowing adaptive events to be triggered in response to the severity (or lack thereof) of an external environment. Such devices have applications in airbag activation, and other safety and surety applications.

  13. Women's History Curriculum Guide.

    ERIC Educational Resources Information Center

    Ruthsdotter, Mary, Ed.; Eisenberg, Bonnie, Ed.

    This curriculum guide is designed to facilitate teachers' first efforts to introduce information about women in U.S. history. The guide promotes a multicultural awareness of women's history beginning with the Native Americans and proceeding to current issues of diversity. Activities are divided for grades 1-6 and 7-12 but may be adapted as…

  14. History of Science

    ERIC Educational Resources Information Center

    Oversby, John

    2010-01-01

    In this article, the author discusses why the history of science should be included in the science curriculum in schools. He also presents some opportunities that can come out of using historical contexts, and findings from a study assessing the place of history of science in readily available textbooks.

  15. Revising Russian History.

    ERIC Educational Resources Information Center

    Wertsch, James V.

    1999-01-01

    Examines the production of new history textbooks that appeared after the breakup of the Soviet Union. Argues that the radical revisions in official history in this context are shaped by the Bakhtinian process of "hidden dialogicality." Suggests that the importance of hidden dialogicality between narrative forms must be considered. (SC)

  16. Teaching Nuclear History.

    ERIC Educational Resources Information Center

    Holl, Jack M.; Convis, Sheila C.

    1991-01-01

    Presents results of a survey of the teaching about nuclear history at U.S. colleges and universities. Reports the existence of a well-established and extensive literature, a focus on nuclear weapons or warfare, and a concentration on nuclear citizenship, therapy, or eschatology for courses outside of history departments. Discusses individual…

  17. Family History Resources.

    ERIC Educational Resources Information Center

    Bookmark, 1991

    1991-01-01

    The 12 articles in this issue focus on the theme of family history resources: (1) "Introduction: Family History Resources" (Joseph F. Shubert); (2) "Work, Credentials, and Expectations of a Professional Genealogist" (Coreen P. Hallenbeck and Lewis W. Hallenbeck); (3) "Computers and Genealogy" (Theresa C. Strasser);…

  18. Teaching and Writing History

    ERIC Educational Resources Information Center

    Meltzer, Milton

    1970-01-01

    Discusses new approaches to teaching history through publishers' series devoted to case studies on social problems, balanced presentation of the contributions of minorities including women, documentary sources, or different viewpoints, all instead of the traditional predigested, summarized history texts. Address delivered at American Association…

  19. An Ozark fire history

    Treesearch

    Richard Guyette; Mavis Dey; Dan Dey

    1999-01-01

    Missouri's natural communities have been shaped by humans and wildland fires for thousands of years. In many ways, the history of fire in Missouri also is a history of human population, culture and migration. Fires caused by natural ignition, like lightning, are rare. Despite as many as 50 to 70 thunderstorm days per year, Conservation Department studies indicate...

  20. Homes in History.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This issue of "The Goldfinch," an Iowa history magazine for children, focuses on issues relating to housing. Articles address such subjects as homelessness, neighborhood history, architecture, and local folklore. One student activity is the "Building Blocks" game that calls upon students to fill in blanks to complete words from…

  1. Writing American Indian History

    ERIC Educational Resources Information Center

    Noley, Grayson B.

    2008-01-01

    The purpose of this paper is to critique the manner in which history about American Indians has been written and propose a rationale for the rethinking of what we know about this subject. In particular, histories of education as regards the participation of American Indians is a subject that has been given scant attention over the years and when…

  2. Six American Histories.

    ERIC Educational Resources Information Center

    Wead, Margaret

    Histories of Blacks, Czechs, Germans, Jews, Mexicans, and Poles are provided in this resource guide. The histories are intended as a major background resource to help instructional staff members of the 45 school systems in Education Service Center, Region II, Corpus Christi, Texas, integrate ethnic heritage studies materials into classroom…

  3. Writing American Indian History

    ERIC Educational Resources Information Center

    Noley, Grayson B.

    2008-01-01

    The purpose of this paper is to critique the manner in which history about American Indians has been written and propose a rationale for the rethinking of what we know about this subject. In particular, histories of education as regards the participation of American Indians is a subject that has been given scant attention over the years and when…

  4. Women's History Curriculum Guide.

    ERIC Educational Resources Information Center

    Ruthsdotter, Mary, Ed.; Eisenberg, Bonnie, Ed.

    This curriculum guide is designed to facilitate teachers' first efforts to introduce information about women in U.S. history. The guide promotes a multicultural awareness of women's history beginning with the Native Americans and proceeding to current issues of diversity. Activities are divided for grades 1-6 and 7-12 but may be adapted as…

  5. On Writing Labor History.

    ERIC Educational Resources Information Center

    Colman, Penny

    1997-01-01

    Examines the personal views, research methods, and writing strategies of an author who specializes in books on labor history aimed at the young adult market. Discusses some of the work that went into biographies of Mother Jones, Rosie the Riveter, and Frances Perkins. Recommends an increased focus on labor history. (MJP)

  6. History. Senior Division.

    ERIC Educational Resources Information Center

    Ontario Dept. of Education, Toronto.

    The publication contains a brief description of three revised programs for teaching senior history. A major aim is to help students understand themselves in relation to the world. Comparison studies relate past to present and an overall interdisciplinary method strengthens the study of history. The focus is on the principle that the course…

  7. Implementing Big History.

    ERIC Educational Resources Information Center

    Welter, Mark

    2000-01-01

    Contends that world history should be taught as "Big History," a view that includes all space and time beginning with the Big Bang. Discusses five "Cardinal Questions" that serve as a course structure and address the following concepts: perspectives, diversity, change and continuity, interdependence, and causes. (CMK)

  8. Preaching in American History.

    ERIC Educational Resources Information Center

    Holland, DeWitte, Ed.

    This volume of twenty essary by nineteen authors attempts to describe the message, issues, and impact of American preaching as it has interacted with history and shaped American churches and society. The twenty topics, treated by individuals with advanced degrees in theology or speech, are: the role of preaching in American history; Puritan…

  9. Re-Righting History.

    ERIC Educational Resources Information Center

    Thornhill, Esmeralda

    1993-01-01

    The traditionally accepted version of the world's story, which ignores achievements and concerns of whole segments of humanity, needs correcting, as a self-determination act of reconstruction and deconstruction by African Americans. Evidence of African presence in the Americas before Columbus and aspects of Canadian history exemplify history that…

  10. History of Science

    ERIC Educational Resources Information Center

    Oversby, John

    2010-01-01

    In this article, the author discusses why the history of science should be included in the science curriculum in schools. He also presents some opportunities that can come out of using historical contexts, and findings from a study assessing the place of history of science in readily available textbooks.

  11. The wet-heat resistance of Bacillus weihenstephanensis KBAB4 spores produced in a two-step sporulation process depends on sporulation temperature but not on previous cell history.

    PubMed

    Baril, E; Coroller, L; Postollec, F; Leguerinel, I; Boulais, C; Carlin, F; Mafart, P

    2011-03-15

    While bacterial spores are mostly produced in a continuous process, this study reports a two-step sporulation methodology. Even though spore heat resistance of numerous spore-forming bacteria is known to be dependent on sporulation conditions, this approach enables the distinction between the vegetative cell growth phase in nutrient broth and the sporulation phase in specific buffer. This study aims at investigating whether the conditions of growth of the vegetative cells, prior to sporulation, could affect spore heat resistance. For that purpose, wet-heat resistance of Bacillus weihenstephanensis KBAB4 spores, produced via a two-step sporulation process, was determined from vegetative cells harvested at four different stages of the growth kinetics, i.e. early exponential phase, late exponential phase, transition phase or early stationary phase. To assess the impact of the temperature on spore heat resistance, sporulation was performed at 10 °C, 20 °C and 30 °C from cells grown during a continuous or a discontinuous temperature process, differentiating or not the growth and sporulation temperatures. Induction of sporulation seems possible for a large range of growth stages. Final spore concentration was not significantly affected by the vegetative cell growth stage while it was by the temperature during growing and sporulation steps. The sporulation temperature influences the heat resistance of B. weihenstephanensis KBAB4 spores much more than growth temperature prior to sporulation. Spores produced at 10 °C were up to 3 times less heat resistant than spores produced at 30 °C.

  12. Active dependency.

    PubMed

    Bornstein, R F

    1995-02-01

    Although dependency has long been associated with passivity, weakness, and submissiveness, a review of the empirical literature reveals that, in certain situations and settings, dependent persons actually exhibit a variety of active, assertive behaviors. In this article, I: a) trace the historical roots of the dependency-passivity link; b) review empirical studies from developmental, social, and clinical psychology which indicate that, in certain circumstances, dependency is associated with active, assertive behavior on the part of the dependent person; c) offer an alternative conceptual model of dependency that accounts for the entire range of behaviors-both passive and active-that are exhibited by the dependent person; and d) discuss the diagnostic and therapeutic implications of this alternative conceptual model of dependency.

  13. 2011 Black History Month

    NASA Image and Video Library

    2011-02-16

    Victoria Webb (center) discusses African-American history during a Black History Month program for John C. Stennis Space Center employees on Feb. 16. Webb, a 103-year-old native of Pass Christian, was guest speaker for the program, sponsored by the Stennis Diversity Council and the Naval Meteorology and Oceanography Command. She was joined in her presentation by Valli Battle (left), a NAVOCEANO employee at Stennis, and friend Jeanell Barnes. Black History Month was first observed in 1976 and is celebrated each February. The 2011 theme was African-Americans and the Civil War.

  14. Life-history strategies of ungulates

    USGS Publications Warehouse

    Leslie, David M.; Bowyer, R.T.; Kie, J.G.

    1999-01-01

    This Special Feature resulted from a symposium on life-history strategies of ungulates presented at the 78th Annual Meeting of the American Society of Mammalogists in Blacksburg, Virginia, in June 1998. The presentations at the symposium represented only a vignette of the wide variety of life-history strategies that exists among ungulates. The four papers that follow include treatises on birth-site selection of moose (Alces alces), sex-ratio correlates with dimorphism and risk of predation, optimal foraging relative to risk of predation, and the role of density dependence in shaping life-history traits of ungulates. A theme of risk of predation in shaping life-history traits is common to three of four papers.

  15. The global history of reionization

    NASA Astrophysics Data System (ADS)

    Greig, Bradley; Mesinger, Andrei

    2017-03-01

    Using a Bayesian framework, we quantify what current observations imply about the history of the epoch of reionization (EoR). We use a popular, three-parameter EoR model, flexible enough to accommodate a wide range of physically plausible reionization histories. We study the impact of various EoR observations: (i) the optical depth to the CMB measured by Planck 2016; (ii) the dark fraction in the Lyman α and β forests; (iii) the redshift evolution of galactic Lyα emission (so-called 'Lyα fraction'); (iv) the clustering of Lyα emitters; (v) the IGM damping wing imprint in the spectrum of QSO ULASJ1120+0641; (vi) and the patchy kinetic Sunyaev-Zel'dovich signal. Combined, (i) and (ii) already place interesting constraints on the reionization history, with the epochs corresponding to an average neutral fraction of (75, 50, 25) per cent, constrained at 1σ to z= (9.21^{+1.22 }_{ -1.15}, 8.14^{+1.08 }_{ -1.00}, 7.26^{+1.13 }_{ -0.96}). Folding-in more model-dependent EoR observations [(iii)-(vi)], strengthens these constraints by tens of per cent, at the cost of a decrease in the likelihood of the best-fitting model, driven mostly by (iii). The tightest constraints come from (v). Unfortunately, no current observational set is sufficient to break degeneracies and constrain the astrophysical EoR parameters. However, model-dependent priors on the EoR parameters themselves can be used to set tight limits by excluding regions of parameter space with strong degeneracies. Motivated by recent observations of z ∼ 7 faint, lensed galaxies, we show how a conservative upper limit on the virial temperature of haloes which host reionizing galaxies can constrain the escape fraction of ionizing photons to f_esc = 0.14^{+0.26 }_{ -0.09}.

  16. History and Legacy

    ERIC Educational Resources Information Center

    Mason, Diana S.

    2004-01-01

    The history of the computer usage in high school laboratories is discussed. Students learned scientific methods by acknowledging measurement errors, using significant digits, questioning their own results, and without doubts, they benefited from applying skill learned in mathematics classes.

  17. Teaching American Environmental History.

    ERIC Educational Resources Information Center

    Strong, Douglas H.

    1974-01-01

    Themes, issues, teaching approaches, and bibliographic references to sources for a course in environmental history, offered with the hope of preparing students to formulate principles to guide our further conduct toward the environment, are described. (JH)

  18. Singing American History.

    ERIC Educational Resources Information Center

    Nielsen, Fred

    2001-01-01

    Discusses how to use music when teaching U.S. History. Provides examples such as teaching about the Civil War, the Great Depression, and the Vietnam War and showing the contributions of African Americans. Includes a discography. (CMK)

  19. Arithmetic and History

    ERIC Educational Resources Information Center

    Josephson, Charles H.

    1970-01-01

    The author discusses how quantitative aspects enrich and clarify our knowledge of history. Statistical concepts of population and economic value are described for the Pilgrims, the American Revolution, and the Civil War. (RS)

  20. History and Legacy

    ERIC Educational Resources Information Center

    Mason, Diana S.

    2004-01-01

    The history of the computer usage in high school laboratories is discussed. Students learned scientific methods by acknowledging measurement errors, using significant digits, questioning their own results, and without doubts, they benefited from applying skill learned in mathematics classes.

  1. History, Passion, and Performance.

    PubMed

    Campbell, Kay N

    2017-04-01

    History, Passion, and Performance was chosen as the theme for the 75th anniversary of the American Association of Occupational Health Nurses (AAOHN) kickoff. The American Association of Occupational Health Nurses has a long history created by passionate, dedicated members. This article highlights historical foundations of the Association, describes the occupational health nurse's passion to drive quality care for workers and discusses future professional and organizational challenges.

  2. Creating a family health history

    MedlinePlus

    Family health history; Create a family health history; Family medical history ... Many factors affect your health. These include your: Genes Diet and exercise habits Environment Family members tend to share certain behaviors, genetic traits, and habits. ...

  3. Sequential dependencies in driving.

    PubMed

    Doshi, Anup; Tran, Cuong; Wilder, Matthew H; Mozer, Michael C; Trivedi, Mohan M

    2012-07-01

    The effect of recent experience on current behavior has been studied extensively in simple laboratory tasks. We explore the nature of sequential effects in the more naturalistic setting of automobile driving. Driving is a safety-critical task in which delayed response times may have severe consequences. Using a realistic driving simulator, we find significant sequential effects in pedal-press response times that depend on the history of recent stimuli and responses. Response times are slowed up to 100 ms in particular cases, a delay that has dangerous practical consequences. Further, we observe a significant number of history-related pedal misapplications, which have recently been noted as a cause for concern in the automotive safety community. By anticipating these consequences of sequential context, driver assistance systems could mitigate the effects of performance degradations and thus critically improve driver safety. Copyright © 2012 Cognitive Science Society, Inc.

  4. [Tobacco dependence].

    PubMed

    Saito, T; Murakami, S

    1998-10-01

    The present review discusses the potential of nicotine psychic and physical dependence. Since the 1964 Surgeon General's Report on Smoking and Health, much attention has been given to nicotine dependence. Many epidemiological studies indicated that about 50% of smokers could be nicotine dependent; however, few of them had the experience of "progressive neglect of alternative pleasures or interest in favour of smoking." Additionally, some clinical and experimental data indicated that nicotine could not be considered more addictive than cocaine and morphine. As to the physical dependence on nicotine, the nicotine withdrawal syndrome is reported to be observed in about 30% of smokers. However, symptoms of the nicotine withdrawal syndrome are not specific but can appear in smokers put under stress. Several investigators have reported that signs of nicotine withdrawal in experimental animals are weaker than those with opioids, barbiturates and alcohol, and have indicated that it is unclear whether behaviors observed in animal models of nicotine physical dependence are signs of the nicotine withdrawal syndrome. From the current review, it can be considered that the potential for nicotine dependence may not be higher than that for other drug dependence and that nicotine physical dependence potential may be weaker than hitherto believed.

  5. [History of chlorosis].

    PubMed

    Tognotti, Eugenia

    2010-01-01

    The once-prevalent disease known as chlorosis, that for centuries has been considered as typical of young unmarried women, is--in the history of Medicine--one of the few for which the abundant medical literature allow to assign the exact date of beginning in the sixteenth century--and its disappearance in early twentieth century. Origin and history of chlorosis--along four centuries--are an intriguing example of how sickness is not only related to the history of medical science, but it is also deeply rooted to the history of the imaginary, mentalities, culture and social trends. But that's not all. In general, through the history of chlorosis it is possible to focus some important issues: the transformation of puberty and adolescence in medical problems; the growing medicalization of the society that is reflected in the gradual inclusion into the scientific medical discourse of social and cultural issues (the status, the emancipation of women, etc...). Using a range of medical writings and treatises, supplemented with statistical data, this article focuses on the spread of the chlorosis--the incidence of which apparently increased at that time--and explores the interpretations of the disease in Nineteenth Century Italy. A "golden age" of medical debate and speculations about the disease, that even after the developments of haematology and its diagnostic identification as hypochromic anaemia, will continue for a long time to carry the weight of the nervous and emotional factors that had accompanied the chlorosis for centuries.

  6. AAS Oral History Project

    NASA Astrophysics Data System (ADS)

    Buxner, Sanlyn; Holbrook, Jarita; AAS Oral History Team

    2016-06-01

    Now in its fourth year, the AAS Oral History Project has interviewed over 80 astronomers from all over the world. Led by the AAS Historical Astronomy Division (HAD) and partially funded by the American Institute of Physics Niels Bohr Library and ongoing support from the AAS, volunteers have collected oral histories from astronomers at professional meetings starting in 2015, including AAS, DPS, and the IAU general assembly. Each interview lasts one and a half to two hours and focuses on interviewees’ personal and professional lives. Questions include those about one’s family, childhood, strong influences on one’s scientific career, career path, successes and challenges, perspectives on how astronomy is changing as a field, and advice to the next generation. Each interview is audio recorded and transcribed, the content of which is checked with each interviewee. Once complete, interview transcripts are posted online as part of a larger oral history library at https://www.aip.org/history-programs/niels-bohr-library/oral-histories. Future analysis will reveal a rich story of astronomers and will help the community address issues of diversity, controversies, and the changing landscape of science. We are still recruiting individuals to be interviewed from all stages of career from undergraduate students to retired and emeritus astronomers. Contact Jarita Holbrook to schedule an interview or to find out more information about the project (astroholbrook@gmail.com). Also, contact Jarita Holbrook if you would like to become an interviewer for the project.

  7. [Affective dependency].

    PubMed

    Scantamburlo, G; Pitchot, W; Ansseau, M

    2013-01-01

    Affective dependency is characterized by emotional distress (insecure attachment) and dependency to another person with a low self-esteem and reassurance need. The paper proposes a reflection on the definition of emotional dependency and the confusion caused by various denominations. Overprotective and authoritarian parenting, cultural and socio-environmental factors may contribute to the development of dependent personality. Psychological epigenetic factors, such as early socio-emotional trauma could on neuronal circuits in prefronto-limbic regions that are essential for emotional behaviour.We also focus on the interrelations between dependent personality, domestic violence and addictions. The objective for the clinician is to propose a restoration of self-esteem and therapeutic strategies focused on autonomy.

  8. History-dependent catastrophes regulate axonal microtubule behavior.

    PubMed

    Stepanova, Tatiana; Smal, Ihor; van Haren, Jeffrey; Akinci, Umut; Liu, Zhe; Miedema, Marja; Limpens, Ronald; van Ham, Marco; van der Reijden, Michael; Poot, Raymond; Grosveld, Frank; Mommaas, Mieke; Meijering, Erik; Galjart, Niels

    2010-06-08

    In Chinese hamster ovary cells, microtubules originate at the microtubule organizing center (MTOC) and grow persistently toward the cell edge, where they undergo catastrophe. In axons, microtubule dynamics must be regulated differently because microtubules grow parallel to the plasma membrane and there is no MTOC. GFP-tagged microtubule plus end tracking proteins (+TIPs) mark the ends of growing neuronal microtubules. Their fluorescent "comet-like" pattern reflects turnover of +TIP binding sites. Using GFP-tagged +TIPs and fluorescence-based segmentation and tracking tools, we show that axonal microtubules grow with a constant average velocity and that they undergo catastrophes at random positions, yet in a programmed fashion. Using protein depletion approaches, we find that the +TIPs CLIP-115 and CLIP-170 affect average microtubule growth rate and growth distance in neurons but not the duration of a microtubule growth event. In N1E-115 neuroblastoma cells, we find that EB1, the core +TIP, regulates microtubule growth rate, growth distance, and duration, consistent with in vitro data. Combined, our data suggest that CLIPs influence the axonal microtubule/tubulin ratio, whereas EB1 stimulates microtubule growth and structural transitions at microtubule ends, thereby regulating microtubule catastrophes and the turnover of +TIP binding sites.

  9. Dinetah: An Early History of the Navajo People.

    ERIC Educational Resources Information Center

    Sundberg, Lawrence D.

    Originally written for Navajo elementary school students, this book chronicles the history of the Navajo people from prehistory to 1868. The book presents a sympathetic history of a people who depended on their tenacity and creative adaptability to survive troubled times. Chapters examine how Navajo culture changed from that of an early hunting…

  10. Political History as Women's History: Toward a More Inclusive Curriculum

    ERIC Educational Resources Information Center

    Woyshner, Christine

    2002-01-01

    The secondary school history curriculum, with its emphasis on political history, tends to relegate women to the margins or to interpret their accomplishments according to a patriarchal framework. The author argues that by adapting theoretical developments in the field of women's history, women can be seen as political agents in history, thereby…

  11. History of psychiatry

    PubMed Central

    Shorter, Edward

    2013-01-01

    Purpose of review The present review examines recent contributions to the evolving field of historical writing in psychiatry. Recent findings Interest in the history of psychiatry continues to grow, with an increasing emphasis on topics of current interest such as the history of psychopharmacology, electroconvulsive therapy, and the interplay between psychiatry and society. The scope of historical writing in psychiatry as of 2007 is as broad and varied as the discipline itself. Summary More than in other medical specialties such as cardiology or nephrology, treatment and diagnosis in psychiatry are affected by trends in the surrounding culture and society. Studying the history of the discipline provides insights into possible alternatives to the current crop of patent-protected remedies and trend-driven diagnoses. PMID:18852567

  12. History of psychology.

    PubMed

    Weidman, Nadine

    2016-02-01

    The editor of History of Psychology discusses her plan to vary the journal's content and expand its scope in specific ways. The first is to introduce a "Spotlight" feature, a relatively brief, provocative thought piece that might take one of several forms. Along with this new feature, she hopes further to broaden the journal's coverage and its range of contributors. She encourages submissions on the history of the psy-sciences off the beaten path. Finally, she plans to continue the journal's tradition of special issues, special sections, and essay reviews of two or more important recently published books in the field. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  13. History of interleukin-4.

    PubMed

    Paul, William E

    2015-09-01

    The history of the discovery and the development of our knowledge of IL-4 exemplifies the path of progress in biomedical science. There are unanticipated twists and turns although progress is made, sometimes quickly, other times far too slowly. Illustrative is the extended time from the first report of IL-4 in 1982 to the establishment of the efficacy of blocking IL-4 and its congener IL-13 in the treatment of moderate to severe asthma and atopic dermatitis, a period of 31years. The author was "present at the creation" and has been a participant or a witness to virtually all the major advances and recounts here his recollection of this history.

  14. Time, money, and history.

    PubMed

    Edgerton, David

    2012-06-01

    This essay argues that taking the economy seriously in histories of science could not only extend the range of activities studied but also change--often quite radically--our understanding of well-known cases and instances in twentieth-century science. It shows how scientific intellectuals and historians of science have followed the money as a means of critique of particular forms of science and of particular conceptions of science. It suggests the need to go further, to a much broader implicit definition of what constitutes science--one that implies a criticism of much history of twentieth-century science for defining it implicitly and inappropriately in very restrictive ways.

  15. Investigating human evolutionary history

    PubMed Central

    WOOD, BERNARD

    2000-01-01

    We rely on fossils for the interpretation of more than 95% of our evolutionary history. Fieldwork resulting in the recovery of fresh fossil evidence is an important component of reconstructing human evolutionary history, but advances can also be made by extracting additional evidence for the existing fossil record, and by improving the methods used to interpret the fossil evidence. This review shows how information from imaging and dental microstructure has contributed to improving our understanding of the hominin fossil record. It also surveys recent advances in the use of the fossil record for phylogenetic inference. PMID:10999269

  16. History of fracture flow

    NASA Astrophysics Data System (ADS)

    Wang, Herbert F.; Doe, Thomas W.

    1990-09-01

    The Committee on the History and Heritage of Hydrology sponsored this special session at the 1990 AGU Spring Meeting, held in Baltimore, Md. The history of fracture flow was an appropriate conclusion to 2 days of papers on the geologic characterization of media heterogeneity. Fracture flow theory developed from several technical disciplines, including rock mechanics and geological engineering in addition to hydrogeology. In particular, the 1960s and 1970s saw major advances in methods for describing and analyzing discontinuous geologic features. Institutions such as the University of California, Berkeley, which had strong interdisciplinary groups in the fields mentioned above, spearheaded much of the technical development.

  17. Louis Shores and Library History.

    ERIC Educational Resources Information Center

    Shiflett, Lee

    2000-01-01

    Presents a history of the American Library History Round Table of the American Library Association (ALA) and describes the role of Louis Shores in its proceedings. Discusses library history, the position of the Round Table within the ALA, and disseminating research in library history. (LRW)

  18. Lessons from the History Books.

    ERIC Educational Resources Information Center

    McKay, Roberta

    1998-01-01

    Expounds on two headline articles from the "Edmonton Journal" (Canada) that prompted the columnist to reflect on the history of the textbook in social studies. The two articles refer to politically motivated editing of history texts in Hong Kong and Japan. Urges history teachers to teach history "the way it happened." (DSK)

  19. Student Papers in Local History.

    ERIC Educational Resources Information Center

    Johnson County Community Coll., Overland Park, KS. Johnson County Center for Local History.

    Thirteen papers on Kansas and Johnson County, Kansas history are presented. The papers were written by students in a course at the Johnson County Center for Local History or for independent study in local history. The papers are: "Conditions and Construction of Gardner Lake"; "The History of St. Joseph's Church, Shawnee,…

  20. What Is World History?

    ERIC Educational Resources Information Center

    Thornton, Stephen J.

    2011-01-01

    In the United States, survey courses in world history have been staples of school programs for almost a century. But no consensus has emerged on the exact goals toward which these courses should be directed. Nor is there agreement on what topics to include or in what order topics should be studied. This article introduces some of the reasons for…

  1. Writing Futures Histories.

    ERIC Educational Resources Information Center

    Humphreys, Les

    The paper presents an innovative approach to the future by examining the concept of time in the 20th century, the development of a sense of chronology, and the role of futures history through the process of "invention." The model is based on the Einsteinian theory of the relativity of time. The author suggests that learning a sense of chronology…

  2. Histories of Geographical Education

    ERIC Educational Resources Information Center

    Kent, Ashley

    2006-01-01

    This paper revisits the value of and justification for histories of geographical education as a field of research endeavour within geographical education. Four potentially fruitful areas of research are identified. These are pressure groups, especially the International Geographical Union's Commission on Geographical Education; the influence of…

  3. Music in Iowa History.

    ERIC Educational Resources Information Center

    Frese, Millie K., Ed.

    1999-01-01

    This theme issue of "The Goldfinch" focuses on music as an art using sound in time to express ideas and emotions and contains articles featuring appreciations of some of Iowa's renowned musical artists. The first article gives an overview of music in Iowa's history. The next article describes Antonin Dvorak's summer sojourn in Spillville…

  4. Kentucky History and Geography.

    ERIC Educational Resources Information Center

    Breckinridge County Board of Education, Hardinsburg, KY.

    Designed for use in grades 6, 7, and 8, this curriculum guide provides 11 individual units for teaching Kentucky history and geography with the recommended text "Kentucky Heritage" published by Steck-Vaughn. Unit titles are The Blue Grass State, Early Explorations of Kentucky, Development of the Government of Kentucky, The Constitution…

  5. Projects in History

    ERIC Educational Resources Information Center

    Harben, Cedric Y.

    1974-01-01

    Discusses two types of historical projects conducted by O-level pupils at Clifton College: studies of famous chemists and projects on the development of industrial chemicals. Indicates that a project in the history of chemistry is characterized by its practical and philosophical approach to chemistry study. (CC)

  6. History in Present Tense.

    ERIC Educational Resources Information Center

    Zakrewsky, Jackie

    1994-01-01

    Eschewing Little Mermaid and Ninja Turtle costumes, students at a Washington Montessori school celebrate Halloween dressed as John Adams, Clara Barton, and other historical figures. U.S. Department of Education recently recognized eight schools for using interdisciplinary approaches, devoting adequate instructional time to history, and addressing…

  7. Epistemology and history.

    PubMed

    de Chadarevian, Soraya

    2013-01-01

    The essay reviews Hans-Jörg Rheinberger's intensive engagement with French epistemology that has remained a constant throughout his career. It focuses especially on a set of recent writings by Rheinberger that all revolve around the question: how has epistemology become historical? This question is discussed in the context of Rheinberger's own move from philosophy to an embracement of history.

  8. History of wood machining

    Treesearch

    Peter Koch

    1967-01-01

    The history of wood machining is closely tied to advanced in metallurgy and power sources. It has been strongly and continuously shaped by prevailing economic forces and the rise and decline of other contemporary industries. This paper sketches a few of the highlights, with emphasis on developments in North America.

  9. Student Grade History System.

    ERIC Educational Resources Information Center

    White, Stephen R.

    This document describes the computerized procedures developed and utilized by Montgomery College (Maryland) to maintain records related to student academic progress. The new system was fully operable by fall 1972. Systems development included: (1) the conversion of past student records to a permanent grade history file; (2) the development of a…

  10. A Biospheric Natural History.

    ERIC Educational Resources Information Center

    Thomashow, Mitchell

    2001-01-01

    A group of Maine birdwatchers recognizes that the presence or absence of migrating songbirds is related to complex biospheric patterns. For schoolchildren, community groups, and environmental scientists, such local natural history observations can be a pathway to perceiving and understanding global ecological change and then to developing…

  11. History and Civility

    ERIC Educational Resources Information Center

    Schaefer, Larry

    2015-01-01

    Larry Schaefer's history of civility is a succinct summary of the implicit and evolving definitions of civility over 2500 years of civilization. Beginning with the Romans and the root word "civitas," meaning the rights and duties of citizenship, civility appears in classical literature as integral to the roots of democracy in the context…

  12. Five Colleges: Five Histories.

    ERIC Educational Resources Information Center

    Story, Ronald, Ed.

    This book presents essays on the histories of five Massachusetts schools of higher education (Amherst College, Mount Holyoke College, the University of Massachusetts at Amherst, Smith College, Hampshire College) who together have had a successful consortia lasting for 25 years. The first essay, by Theodore P. Greene, depicts the temper of Amherst…

  13. History of vaccination.

    PubMed

    Plotkin, Stanley

    2014-08-26

    Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologic markers. In the 21st century, molecular biology permits vaccine development that was not possible before.

  14. History at NASA

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The efforts of the National Aeronautics and Space Administration to capture and record the events of the past are described, particularly the research accomplishments of NASA's agency-wide history program. A concise guide to the historical research resources available at NASA Headquarters in Washington, D.C., at NASA facilities around the country, and through the federal records systems is given.

  15. Teaching Local History.

    ERIC Educational Resources Information Center

    Singer, Alan, Ed.

    2003-01-01

    This Social Science Docket theme issue focuses on teaching local history and included theme and non-themed articles, lesson plans, learning activities, and book, movie, and museum reviews designed for K-12 social studies teachers. Articles and materials in this issue are: "Editing Is Not Censorship" (Alan Singer); "Teachers Respond…

  16. In a Word, History

    ERIC Educational Resources Information Center

    Dohan, Mary Helen

    1977-01-01

    Understanding words like "bionics" will open the mind to the horizons of another time when words like "railroad" evoked wonder and "to fly to the moon" was a metaphor for the impossible dream. Suggests that history teachers and English teachers should join together in using words to teach both subjects. (Editor/RK)

  17. A History of Psychology.

    ERIC Educational Resources Information Center

    Brown, Evan L.

    Any study of the history of psychology must first determine what is to be considered psychology, whether to stick to the relatively continuous Western tradition or to include others (e.g., Eastern, Oriental), and whether to investigate the impact of the socio-cultural events of the time on the views of that period or consider those views in a…

  18. Bengal Literature and History.

    ERIC Educational Resources Information Center

    Dimock, Edward C., Jr., Ed.

    The unifying theme of the papers in this book is the use of creative literature as source material for the study of cultural history. Titles and authors of the papers are: "Encounter and Growth in Bengali Literature, A Survey of Medieval Bengali Literature" by T.W. Clark; "The Hindu Chiefdom in Middle Bengali Literature" by…

  19. The History Education Project.

    ERIC Educational Resources Information Center

    Seifman, Eli

    In addition to briefly intoducing the History Education Project (HEP) sponsored by the American Historical Association and Indiana University, and funded by USOE, this report announces the establishment (Spring, 1970) of a regional HEP team at Stony Brook, describes its tentative plan of operation, and solicits assistance from the community. The…

  20. A Little History (Invited)

    NASA Astrophysics Data System (ADS)

    Eagleson, P. S.

    2009-12-01

    Seeds of the Blue Book were planted in Cambridge, MA in the early 1960's, and variants thereof in Boulder, Colorado and Tucson, Arizona at a somewhat later date. However, flowering and cross-pollination did not occur until 1984 with the fruit ripening in 1991. We will briefly review this obscure history, search for lessons learned, and ponder what comes next.

  1. Narrative History and Theory

    ERIC Educational Resources Information Center

    Tamura, Eileen H.

    2011-01-01

    While narrative history has been the prevailing mode in historical scholarship, its preeminence has not gone unquestioned. In the 1980s, the role of narrative in historical writing was "the subject of extraordinarily intense debate." The historical backdrop of this debate can be traced to the preceding two decades, when four groups of thinkers…

  2. History, Theory, and Education

    ERIC Educational Resources Information Center

    Rury, John L.

    2011-01-01

    In this article, the author discusses the question of theory as it may pertain to the history of education, with particular attention to the United States. Historians, like everyone else, have little choice regarding the use of theory; to one extent or another they must. The question is how much and to what end. The author aims to consider the…

  3. Narrative History and Theory

    ERIC Educational Resources Information Center

    Tamura, Eileen H.

    2011-01-01

    While narrative history has been the prevailing mode in historical scholarship, its preeminence has not gone unquestioned. In the 1980s, the role of narrative in historical writing was "the subject of extraordinarily intense debate." The historical backdrop of this debate can be traced to the preceding two decades, when four groups of thinkers…

  4. Life History and Identity

    ERIC Educational Resources Information Center

    Tierney, William G.

    2013-01-01

    This article uses the life history method to chronicle the challenges of a low-income, first-generation student en route to college. The paper addresses three questions: how Manuel navigates college and related topics such as roommates, family, and money; how he creates social networks; and how he works with adults such as teachers and…

  5. AFA-NIET History.

    ERIC Educational Resources Information Center

    Yates, Guy; Schnoor, Larry

    2000-01-01

    Presents a history of the American Forensic Association regarding its splintering within the forensic community. Discusses the incorporation of the National Individual Events Tournament (NIET). Considers how the NIET Committee has encouraged research projects related to forensic pedagogy as well as other issues related to forensics. (NH)

  6. Ancient Egypt: History 380.

    ERIC Educational Resources Information Center

    Turk, Laraine D.

    "Ancient Egypt," an upper-division, non-required history course covering Egypt from pre-dynastic time through the Roman domination is described. General descriptive information is presented first, including the method of grading, expectation of student success rate, long-range course objectives, procedures for revising the course, major…

  7. Black History Speech

    ERIC Educational Resources Information Center

    Noldon, Carl

    2007-01-01

    The author argues in this speech that one cannot expect students in the school system to know and understand the genius of Black history if the curriculum is Eurocentric, which is a residue of racism. He states that his comments are designed for the enlightenment of those who suffer from a school system that "hypocritically manipulates Black…

  8. A History of Multimedia.

    ERIC Educational Resources Information Center

    Burke, Larry Kenneth

    The history of multimedia and descriptions of various multimedia events from 1900 to 1972 are presented. The development of multimedia events is described for four eras and four main classifications of events: multiscreen presentations, electronic media and performers, environmental theater, and environments. Five appendixes include a discussion…

  9. Indian Law Enforcement History.

    ERIC Educational Resources Information Center

    Etheridge, David

    Written as a tribute to American Indian law enforcement officers and the Indian Criminal Justice System, this monographh details the history of the legislative, judicial, financial, and cultural problems associated with the development of Indian law enforcement. Citing numerous court cases, pieces of legislation, and individual and organizational…

  10. Brazilian History through Journalism.

    ERIC Educational Resources Information Center

    Zaher, Celia Ribeiro; Varella, Maria Angelica

    This paper provides an overview of the beginnings of the newspaper in Brazil with information on the more significant titles and their role in the history of journalism and their impact on social change that occurred between the Imperial and Republican periods. Current collections at the National Library and legal deposit are discussed. It…

  11. The History Computerization Project.

    ERIC Educational Resources Information Center

    Clark, David L.

    1992-01-01

    Description of the History Computerization Project, which is being developed for the exchange of information between researchers, librarians, archivists, museum curators, preservation groups, and historical societies, focuses on workshops that teach the use of computer database management for historical cataloging and research. (LRW)

  12. History of vaccination

    PubMed Central

    Plotkin, Stanley

    2014-01-01

    Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologic markers. In the 21st century, molecular biology permits vaccine development that was not possible before. PMID:25136134

  13. Kentucky History and Geography.

    ERIC Educational Resources Information Center

    Breckinridge County Board of Education, Hardinsburg, KY.

    Designed for use in grades 6, 7, and 8, this curriculum guide provides 11 individual units for teaching Kentucky history and geography with the recommended text "Kentucky Heritage" published by Steck-Vaughn. Unit titles are The Blue Grass State, Early Explorations of Kentucky, Development of the Government of Kentucky, The Constitution…

  14. Projects in History

    ERIC Educational Resources Information Center

    Harben, Cedric Y.

    1974-01-01

    Discusses two types of historical projects conducted by O-level pupils at Clifton College: studies of famous chemists and projects on the development of industrial chemicals. Indicates that a project in the history of chemistry is characterized by its practical and philosophical approach to chemistry study. (CC)

  15. Why Military History?

    ERIC Educational Resources Information Center

    Bunting, Josiah, III

    2008-01-01

    Interest in military history is as strong as it has ever been--except on American college campuses. Lt. Gen. Josiah Bunting III examines why today's undergraduates need to study the facts of war, and why knowing its causes and consequences remain a vital part of our common knowledge.

  16. Making Invisible Histories Visible

    ERIC Educational Resources Information Center

    Hanssen, Ana Maria

    2012-01-01

    This article features Omaha Public Schools' "Making Invisible Histories Visible" program, or MIHV. Omaha's schools have a low failure rate among 8th graders but a high one among high school freshmen. MIHV was created to help at-risk students "adjust to the increased demands of high school." By working alongside teachers and…

  17. Five Colleges: Five Histories.

    ERIC Educational Resources Information Center

    Story, Ronald, Ed.

    This book presents essays on the histories of five Massachusetts schools of higher education (Amherst College, Mount Holyoke College, the University of Massachusetts at Amherst, Smith College, Hampshire College) who together have had a successful consortia lasting for 25 years. The first essay, by Theodore P. Greene, depicts the temper of Amherst…

  18. History in Present Tense.

    ERIC Educational Resources Information Center

    Zakrewsky, Jackie

    1994-01-01

    Eschewing Little Mermaid and Ninja Turtle costumes, students at a Washington Montessori school celebrate Halloween dressed as John Adams, Clara Barton, and other historical figures. U.S. Department of Education recently recognized eight schools for using interdisciplinary approaches, devoting adequate instructional time to history, and addressing…

  19. Testing History As Inquiry

    ERIC Educational Resources Information Center

    Miller, James R.; Hart, James

    1973-01-01

    Some obvious difficulties of teaching and testing history as inquiry are reviewed. Examples of test items that require students to utilize thought processes developed through inquiry teaching are presented together with a rationale for their use. Bloom's Taxonomy of Educational Objectives is proposed as a useful tool in test construction. (SM)

  20. Psychology and History.

    ERIC Educational Resources Information Center

    Munsterburg, Hugo

    1994-01-01

    This essay considers the discipline of psychology as distinct from history, defining it as a science within philosophy dedicated to the study of the causal structure of the human mind. Although Hugo Munsterburg was considered an important figure in applied psychology, this essay represents an earlier epistemology. (SLD)

  1. History, Theory, and Education

    ERIC Educational Resources Information Center

    Rury, John L.

    2011-01-01

    In this article, the author discusses the question of theory as it may pertain to the history of education, with particular attention to the United States. Historians, like everyone else, have little choice regarding the use of theory; to one extent or another they must. The question is how much and to what end. The author aims to consider the…

  2. My English History.

    ERIC Educational Resources Information Center

    Sommer, Paul

    2003-01-01

    Outlines the author's history as an English teacher. Suggests that English teaching is not hermetic but profoundly influenced by educational trends outside the subject itself. Explains that the author's commitment to English combines a sense of engagement with a sense of liberation. (PM)

  3. Black History Month.

    ERIC Educational Resources Information Center

    Web Feet K-8, 2000

    2000-01-01

    This annotated subject guide to Web sites and additional resources focuses on Black History month. Specifies age levels for resources that include Web sites, CD-ROMs and software, videos, books, audios, magazines; includes professional resources; and presents a relevant class activity. (LRW)

  4. Gill's 'History' restored

    NASA Astrophysics Data System (ADS)

    Hurn, Mark

    2009-06-01

    Note about the restoration of the copy of Sir David Gill's 'A History and Description of the Royal Observatory, Cape of Good Hope' in the Library of the Institute of Astronomy, Cambridge. The book was restored with funds provided by the SHA in thanks for facilities for meetings provided to the Institute.

  5. History of Vietnamese Literature.

    ERIC Educational Resources Information Center

    Duong Quang Ham

    This is the first of a two-volume textbook, covering the official program of the Ministry of Education, of the secondary curriculum for the history of Vietnamese literature. It is divided into three main sections. The first section "First Year of the Secondary Cycle (Grade 11)" deals with (1) popular literature; (2) the influence of China, (3)…

  6. In a Word, History

    ERIC Educational Resources Information Center

    Dohan, Mary Helen

    1977-01-01

    Understanding words like "bionics" will open the mind to the horizons of another time when words like "railroad" evoked wonder and "to fly to the moon" was a metaphor for the impossible dream. Suggests that history teachers and English teachers should join together in using words to teach both subjects. (Editor/RK)

  7. Ancient Egypt: History 380.

    ERIC Educational Resources Information Center

    Turk, Laraine D.

    "Ancient Egypt," an upper-division, non-required history course covering Egypt from pre-dynastic time through the Roman domination is described. General descriptive information is presented first, including the method of grading, expectation of student success rate, long-range course objectives, procedures for revising the course, major…

  8. [Brief history of dreams].

    PubMed

    Rosselli, D

    Throughout history dreams have played a crucial role. Dreams have inspired great works of art, solved scientific problems and, because of the premonitory value attached to them, have influenced transcendental decisions. This paper reviews some of the dreams that have been a part of the world's literature and historical tradition.

  9. A History of Psychology.

    ERIC Educational Resources Information Center

    Brown, Evan L.

    Any study of the history of psychology must first determine what is to be considered psychology, whether to stick to the relatively continuous Western tradition or to include others (e.g., Eastern, Oriental), and whether to investigate the impact of the socio-cultural events of the time on the views of that period or consider those views in a…

  10. Footsteps through History.

    ERIC Educational Resources Information Center

    Hawkins, Michael L.

    1984-01-01

    Using colored construction paper, students trace around their shoes and cut out two forms. Students then pick and research an event from the time period in history under study and write a report on the representations of shoe soles. The reports are taped, in order of occurrence, around the classroom. (RM)

  11. Redefining American Literary History.

    ERIC Educational Resources Information Center

    Ruoff, A. LaVonne Brown, Ed.; Ward, Jerry W., Jr., Ed.

    This book is a collection of essays which provide starting points for a redefinition of American literary history based on a multiethnic and multiracial, rather than European, theory of culture. After an introduction by the editors, essays in the book are: "The Literatures of America: A Comparative Discipline" (Paul Lauter);…

  12. Picturing Iowa's History.

    ERIC Educational Resources Information Center

    Ruth, Amy, Ed.

    1994-01-01

    This issue focuses on how advancements in photography affected Iowans and the pictures they took of their communities. Five famous and not so famous photographers who have taken pictures of Iowa's history are featured: (1) John Plumbe, Jr.; (2) Isaac A. Wetherby; (3) D. C. Hale; (4) Duluth Pieper; and (5) E. M. Clark. Instructions for making…

  13. History of Space Policy

    DTIC Science & Technology

    2012-03-22

    2012), 1. 2 Winston Churchill, http://www.brainyquote.com/quotes/keywords/history.html (accessed January 8, 2012). 3 Deborah Cadbury , Space Race... Cadbury , Space Race, The Epic Battle Between America and the Soviet Union for Dominion of Space (New York: Harper Collins, 2006), 4. 22 7 Ibid., 5

  14. Understanding World Economic History

    ERIC Educational Resources Information Center

    Whaples, Robert

    2013-01-01

    One joy of studying history is discovering people living meaningful lives and behaving in unusual ways that are startling to the modern reader--young or old. Why did pre-modern people living hundreds or even thousands of years ago do things so differently than we do? Robert Whaples states that Economic historians conclude that the key difference…

  15. Understanding World Economic History

    ERIC Educational Resources Information Center

    Whaples, Robert

    2013-01-01

    One joy of studying history is discovering people living meaningful lives and behaving in unusual ways that are startling to the modern reader--young or old. Why did pre-modern people living hundreds or even thousands of years ago do things so differently than we do? Robert Whaples states that Economic historians conclude that the key difference…

  16. Freud and cultural history.

    PubMed

    Burke, Peter

    2007-01-01

    This article is concerned with three questions: Can historians make use of Freud's ideas? Have they done so in the past? Should they do so in the future? It begins with a personal encounter with Freud's ideas and then raises some general questions about the relation between psychoanalysis and history.

  17. Runaways in History

    ERIC Educational Resources Information Center

    Lipschutz, Mark R.

    1977-01-01

    Although running away is a glorified part of American folk tradition, today's runaway runs afoul of a host of laws, including those which make the act itself illegal. This article examines the history of the social and legal status of youth and why they run away. (Author)

  18. The Holocaust and History.

    ERIC Educational Resources Information Center

    Singer, Alan, Ed.

    2003-01-01

    This theme based journal issue consists of articles and teaching ideas focusing on the Holocaust and history. This publication contains the following materials: (1) "Multiple Perspectives on the Holocaust?" (Alan Singer); (2) "Responses to 'Multiple Perspectives on the Holocaust'"; (3) "Escape to Cuba: Story of Laura Kahn,…

  19. History Comes Alive.

    ERIC Educational Resources Information Center

    Shultz, Gary

    This chapter describes the development of a set of programs called "History Comes Alive," a series of historical simulations and interactive experiences for students at heritage sites in Ontario. The programs allow students from Ontario and New York to relive the past by spending 3 days and 2 nights in a simulated historical setting. In…

  20. Using Histories to Implement Atomic Objects

    NASA Technical Reports Server (NTRS)

    Ng, Pui

    1987-01-01

    In this paper we describe an approach of implementing atomicity. Atomicity requires that computations appear to be all-or-nothing and executed in a serialization order. The approach we describe has three characteristics. First, it utilizes the semantics of an application to improve concurrency. Second, it reduces the complexity of application-dependent synchronization code by analyzing the process of writing it. In fact, the process can be automated with logic programming. Third, our approach hides the protocol used to arrive at a serialization order from the applications. As a result, different protocols can be used without affecting the applications. Our approach uses a history tree abstraction. The history tree captures the ordering relationship among concurrent computations. By determining what types of computations exist in the history tree and their parameters, a computation can determine whether it can proceed.

  1. Opioid dependence

    PubMed Central

    2009-01-01

    Introduction Dependence on opioids is a multifactorial condition involving genetic and psychosocial factors. There are three approaches to treating opioid dependence. Stabilisation is usually by opioid substitution treatments, and aims to ensure that the drug use becomes independent of mental state (such as craving and mood) and independent of circumstances (such as finance and physical location). The next stage is to withdraw (detox) from opioids. The final aim is relapse prevention. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments for stabilisation (maintenance) in people with opioid dependence? What are the effects of drug treatments for withdrawal in people with opioid dependence? What are the effects of drug treatments for relapse prevention in people with opioid dependence? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2008 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 23 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: buprenorphine; clonidine; lofexidine; methadone; naltrexone; and ultra-rapid withdrawal regimes. PMID:21696648

  2. [Personality dependence in drug dependence].

    PubMed

    Cormier, D; Reid, N

    1979-11-01

    Is drug dependence more likely to establish itself in persons whose personality structure is already characterized by a psychological dependence which can be looked at from two aspects: cognitive field dependence and emotional dependence? Three groups of 21 subjects each, multiple drug users, users of cannabis and non-users, are studied with the expectation that the first group is more psychologically dependent than the second one, the latter being in turn more dependent than the group of non-users. The situation is not so simple. Hard-drug users appear to be more active than users of cannabis, whereas non-users are even more dynamic individuals. However, in such a study the duration of consumption exercise an important influence because, in this regard, different personality profiles of the two drug-using groups come into play, the users of cannabis presenting a more incoherent picture. The multiple drug addict selected from his natural environment seems to acquire, through his prolonged consumption, a greater perceptual independence and emotional maturity owing to the clandestine nature of his habit, and a more acute and articulate general way of functioning in order to avoid mishaps.

  3. Life history evolution: successes, limitations, and prospects

    NASA Astrophysics Data System (ADS)

    Stearns, Stephen C.

    Life history theory tries to explain how evolution designs organisms to achieve reproductive success. The design is a solution to an ecological problem posed by the environment and subject to constraints intrinsic to the organism. Work on life histories has expanded the role of phenotypes in evolutionary theory, extending the range of predictions from genetic patterns to whole-organism traits directly connected to fitness. Among the questions answered are the following: Why are organisms small or large? Why do they mature early or late? Why do they have few or many offspring? Why do they have a short or a long life? Why must they grow old and die? The classical approach to life histories was optimization; it has had some convincing empirical success. Recently non-equilibrium approaches involving frequency-dependence, density-dependence, evolutionary game theory, adaptive dynamics, and explicit population dynamics have supplanted optimization as the preferred approach. They have not yet had as much empirical success, but there are logical reasons to prefer them, and they may soon extend the impact of life history theory into population dynamics and interspecific interactions in coevolving communities.

  4. A History of Nanobubbles.

    PubMed

    Alheshibri, Muidh; Qian, Jing; Jehannin, Marie; Craig, Vincent S J

    2016-11-01

    We follow the history of nanobubbles from the earliest experiments pointing to their existence to recent years. We cover the effect of Laplace pressure on the thermodynamic stability of nanobubbles and why this implies that nanobubbles are thermodynamically never stable. Therefore, understanding bubble stability becomes a consideration of the rate of bubble dissolution, so the dominant approach to understanding this is discussed. Bulk nanobubbles (or fine bubbles) are treated separately from surface nanobubbles as this reflects their separate histories. For each class of nanobubbles, we look at the early evidence for their existence, methods for the production and characterization of nanobubbles, evidence that they are indeed gaseous, or otherwise, and theories for their stability. We also look at applications of both surface and bulk nanobubbles.

  5. Sequence History Update Tool

    NASA Technical Reports Server (NTRS)

    Khanampompan, Teerapat; Gladden, Roy; Fisher, Forest; DelGuercio, Chris

    2008-01-01

    The Sequence History Update Tool performs Web-based sequence statistics archiving for Mars Reconnaissance Orbiter (MRO). Using a single UNIX command, the software takes advantage of sequencing conventions to automatically extract the needed statistics from multiple files. This information is then used to populate a PHP database, which is then seamlessly formatted into a dynamic Web page. This tool replaces a previous tedious and error-prone process of manually editing HTML code to construct a Web-based table. Because the tool manages all of the statistics gathering and file delivery to and from multiple data sources spread across multiple servers, there is also a considerable time and effort savings. With the use of The Sequence History Update Tool what previously took minutes is now done in less than 30 seconds, and now provides a more accurate archival record of the sequence commanding for MRO.

  6. Space telescope history project

    NASA Astrophysics Data System (ADS)

    Historians of science from the Johns Hopkins University and the Smithsonian Institution's National Air and Space Museum have begun an historical study of the development of the Space Telescope.The Space Telescope Historical Project, designed to enhance the public's understanding of the Space Telescope, is under the direction of Robert Kargon, the Willis K. Shepard Professor and chairman of the department of history of science at Johns Hopkins, and Paul Hanle, chairman of the department of space science and exploration at the National Air and Space Museum. One of the goals of the project is to write a history of the telescope and to publish it at a time proximate to the telescope's launch, which is scheduled for early 1985.

  7. Stress and life history.

    PubMed

    Monaghan, Pat; Spencer, Karen A

    2014-05-19

    In his book on behavioural endocrinology, Randy Nelson describes 'stress' as a 'notoriously ethereal concept'. Yet, despite this lack of clarity, studies of the consequences of stress across different time scales, life history stages, taxa and levels of biological enquiry form a large part of modern biology and biomedicine. Organisms need to recognise and respond to environmental challenges. Being able to do so appropriately, and with minimal costs, is an important physiological attribute, with great adaptive value. The costs and benefits of different mechanisms that enable organisms to cope with unpredictable environmental changes can be manifest to different degrees at different life stages. Accordingly, the level of stress experienced in the environment can act as a strong selective pressure that drives the evolution of life histories.

  8. History of Korean Neurosurgery.

    PubMed

    Hwang, Sung-nam

    2015-08-01

    The year 2012 was the 50th anniversary of the Korean Neurosurgical Society, and in 2013, the 15th World Congress of Neurosurgery took place in Seoul, Korea. Thus, it is an appropriate occasion to introduce the world to the history of the Korean Neurosurgical Society and the foundation, development, and growth of Korean neurosurgery. Historical materials and pictures were collected and reviewed from the history book and photo albums of the Korean Neurosurgical Society. During the last 50 years, the Korean Neurosurgical Society and Korean neurosurgery have developed and grown enormously not only in quantity but also in quality. In every aspect, the turning point from the old to the new era of the Korean Neurosurgical Society and Korean neurosurgery was the year 1980. Copyright © 2015. Published by Elsevier Inc.

  9. [Arthritis and clinical history].

    PubMed

    Silva, Lígia; Sampaio, Luzia; Pinto, José; Ventura, Francisco S

    2011-01-01

    In front of a patient with arthritis, clinical good-sense tells that the most probable diagnosis are the most prevalent ones. Nevertheless, we have to exclude a multiplicity of other aetiologies, less frequent, but with highest implications in the therapeutic conduct. Infections by Brucella and by Borrelia are rare causes of chronic arthritis, yet are diagnosis to consider, even when the clinical manifestations aren't the most typical, as there still exist endemic areas in Portugal. Here we report two clinical cases about patients with arthritis for more than one year, subject to ineffective exams ant treatments. Only the clinical history could put on evidence clinical-epidemiological data, suggestive of Brucellosis and Lyme Disease, namely the professional contact with infected animals, and the history of probable erythema migrans, that pointed toward the correct diagnosis. So, with directed therapeutic, there was complete resolution of the inflammatory symptoms.

  10. Assembly history dictates ecosystem functioning: evidence from wood decomposer communities.

    PubMed

    Fukami, Tadashi; Dickie, Ian A; Paula Wilkie, J; Paulus, Barbara C; Park, Duckchul; Roberts, Andrea; Buchanan, Peter K; Allen, Robert B

    2010-06-01

    Community assembly history is increasingly recognized as a fundamental determinant of community structure. However, little is known as to how assembly history may affect ecosystem functioning via its effect on community structure. Using wood-decaying fungi as a model system, we provide experimental evidence that large differences in ecosystem functioning can be caused by small differences in species immigration history during community assembly. Direct manipulation of early immigration history resulted in three-fold differences in fungal species richness and composition and, as a consequence, differences of the same magnitude in the rate of decomposition and carbon release from wood. These effects - which were attributable to the history-dependent outcome of competitive and facilitative interactions - were significant across a range of nitrogen availabilities observed in natural forests. Our results highlight the importance of considering assembly history in explaining ecosystem functioning.

  11. A passion for history

    NASA Astrophysics Data System (ADS)

    Marshall, Robin

    2008-02-01

    While walking through the recently refurbished physics department at Manchester University with its newly painted walls and gleaming windows, a sense of history is never far behind. Many famous physicists have worked and studied at the university, including Ernest Rutherford, J J Thomson, William Bragg and James Chadwick. Indeed, when Albert Einstein came to the UK in 1921, it was at Manchester that he gave his first lecture to a British audience.

  12. The history of IUE

    NASA Technical Reports Server (NTRS)

    Boggess, Albert; Meredith, Leslie M.; Wilson, Robert; Barker, Peter J.

    1987-01-01

    The early organizational and development history of the NASA-ESA-SERC International UV Explorer (IUE) satellite observatory is reviewed. Consideration is given to the progress of UV astronomy prior to the launch of the IUE in 1978; the initial feasibility and design studies; preliminary proposals (e.g., UVAS) and the reasons for their rejection; the designs selected for the telescope, spectrographs, detectors, and attitude-control system; the preflight preparations; and the commissioning phase.

  13. Brief History of Syphilis

    PubMed Central

    Tampa, M; Sarbu, I; Matei, C; Benea, V; Georgescu, SR

    2014-01-01

    Abstract Before the discovery of Treponema pallidum as the etiologic agent, the origins of syphilis have been the subject of several debates. Diverse therapeutic agents were employed in an attempt to cure the disease. Examining the milestones in the history of syphilis, the present article reviews the existing theories that tried to explain the origins of the disease, the approach in art, the cultural and the evolution of the treatments from the empiric means to the discovery of penicillin. PMID:24653750

  14. Alcohol in human history.

    PubMed

    Vallee, B L

    1994-01-01

    The role of ethanol in the history of human development is here summarized under seven topics: I. Alcohol: the substitute for water as the major human beverage; II. Alcohol as a component of the diet and source of calories; III. Alcohol, concentration by distillation; IV. The Reformation, Temperance and Prohibition; V. Potable nonalcoholic beverages: Boiled water (coffee, tea); VI. Purification and sanitation of water; VII. The present and future.

  15. History of hadrontherapy

    NASA Astrophysics Data System (ADS)

    Amaldi, Ugo

    2015-05-01

    Hadrontherapy is today an established modality in cancer radiation therapy. Based on the superior ballistic and radiobiological properties of accelerated ions, this discipline experienced a remarkable growth in the last 20 years. This paper reviews the history of hadrontherapy, from the early days to the most recent developments. In particular, the evolution of proton and carbon ion therapy is presented together with a glance at future solutions such as single-room facilities.

  16. Industrial Case Histories

    DTIC Science & Technology

    2001-04-05

    for each analysis will helpfully dispel this theory. Key Words: Imbalance; Blade Pass; Whirl; Whip; Structural Resonance ; Variable Frequency Drives...Tower Blade Pass Resonance Problem: This unit had a history of running high vibration amplitudes in the 20 Hz frequency range. The operating speed of...and created their own problem. If the time had been spent performing resonance checks before making the change, this problem would have been

  17. The Trouble with History

    DTIC Science & Technology

    2005-01-01

    regards, the post-structuralist theories of Michel Foucault, the deconstruc- tionist notions of Jacques Derrida , and Dominick LaCapra’s techniques of...is closer to fiction than nonfiction. Indeed, they have a point. Compare: Frank Ankersmit, “Historiography and Postmodernism ,” History and Theory, 28...Historiography in the Twentieth Century: From Scientific Objectivity to the Postmodern Challenge (Hanover, N.H.: Wesleyan Univ. Press, 1997) and Evans

  18. The history of liposuction.

    PubMed

    Ahern, Ryan William

    2009-12-01

    This article aims to familiarize the reader with the history of liposuction. The author documents the landmark events and characters in the development of this revolutionary and widely known procedure. Included is a historical discussion of the obstacles and the triumphs the practitioners and the procedure itself has seen, as well as a review of relevant scientific data placed in its appropriate historical context up through modern day.

  19. Opioid dependence

    PubMed Central

    2011-01-01

    Introduction Dependence on opioids is a multifactorial condition involving genetic and psychosocial factors. There are three stages to treating opioid dependence. Stabilisation is usually by opioid substitution treatments, and aims to ensure that the drug use becomes independent of mental state (such as craving and mood) and independent of circumstances (such as finance and physical location). The next stage is to withdraw (detox) from opioids. The final stage is relapse prevention. This treatment process contributes to recovery of the individual, which also includes improved overall health and wellbeing, as well as engagement in society. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments for stabilisation (maintenance) in people with opioid dependence? What are the effects of drug treatments for withdrawal in people with opioid dependence? What are the effects of drug treatments for relapse prevention in people with opioid dependence? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 26 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: buprenorphine; clonidine; lofexidine; methadone; naltrexone; and ultra-rapid withdrawal regimens. PMID:21929827

  20. Troubling Histories and Theories: Gender and the History of Education.

    ERIC Educational Resources Information Center

    Goodman, Joyce

    2003-01-01

    Discusses gender influences and ways that history and theory have interacted in influencing women's contribution and recognition in educational history. Focuses on several historians' views and how some have eventually written women back into the historical picture of education. (KDR)

  1. Periodic sequences of simple maps can support chaos

    NASA Astrophysics Data System (ADS)

    Cánovas, Jose S.

    2017-01-01

    In this paper, we explore the Parrondo's paradox when several dynamically simple maps are combined in a periodic way, producing chaotic dynamics. We show that the paradox is not commutative, that is, it depends on the way that the maps are iterated. We also see that the paradox happens more frequently when the number of maps that we iterate increases.

  2. Functions of History Education: History Teacher Trainees' Perspective

    ERIC Educational Resources Information Center

    Akinoglu, Orhan

    2009-01-01

    The purpose of this study is to investigate history teacher trainees' views and perceptions of the functions of history education. 36 teacher trainees participated in the study. All of the participants were registered to the History Education masters degree (without dissertation), within the Secondary Education Social Sciences discipline at…

  3. Amityville Memorial High School History Journal Advance Placement History.

    ERIC Educational Resources Information Center

    Howlett, Charles F., Ed.

    The history of Amityville, New York, compiled by 11th and 12th grade advance placement history students, is presented in journal form. Six papers focus on: (1) South Oaks: The Long Island Home; (2) A History of Bethel African Methodist Episcopal Church, Amityville; (3) Amityville: A Vacationland; (4) Amityville School System from 1904 to Present;…

  4. History Teachers Are Not Historians! Theme: Why Teach History?

    ERIC Educational Resources Information Center

    Paget, Gregory

    1989-01-01

    Suggests that the imposition of order on history perpetuates a historian/history teacher dichotomy. Illustrates prevailing fallacies in the teaching of history: (1) the moniker fallacy; (2) the one-school fallacy; (3) the contextual fallacy; and (4) the wave fallacy. States that an avoidance of these fallacies will at least partially reconcile…

  5. Disciplinary History and the Situation of History Teachers

    ERIC Educational Resources Information Center

    Fordham, Michael

    2012-01-01

    A growing consensus in the history education community supports the idea that the discipline of history provides the best opportunity for moving beyond a "nation-building" or "skills-based" approach to teaching about the past. The social and temporal characteristics of the discipline of history mean such conclusions have…

  6. From Written Film History to Visual Film History.

    ERIC Educational Resources Information Center

    Petric, Vladimir

    The poor quality of most university courses in film history is due to several factors, among them the fact that there is insufficient analytical documentation and direct cinematic illustration in existent written film histories. These histories examine films on a thematic level, offering noncinematic interpretation such as literary meaning, social…

  7. Integrating Men's History into Women's History: A Proposition

    ERIC Educational Resources Information Center

    Zook, Melinda S.

    2002-01-01

    In the late 1970s and early 1980s, "The History Teacher" published several articles on the importance and process of integrating women's history into "regular history." Now, at the dawn of the twenty-first century, the author suggests to add a new perspective as to how teachers think about and teach gender in the classroom.…

  8. Teacher Candidates' Attitudes to Using Oral History in History Education

    ERIC Educational Resources Information Center

    Demircioglu, Ebru

    2016-01-01

    The aim of this research is to determine the views of history teacher candidates towards an oral history project carried out in the Special Teaching Method Course of the history pedagogy program of the Fatih Faculty of Education (FFE) at Karadeniz Technical University in Turkey. An open-ended questionnaire and semi-structured interview were the…

  9. The History of Secondary Education in History of Education

    ERIC Educational Resources Information Center

    McCulloch, Gary

    2012-01-01

    "History of Education" has published a steady stream of papers on the history of secondary education over the first 40 years of its existence. This corpus of research has been generated in the context of renewed interest in the history of secondary education that has been stimulated by developments in social and historical inquiry as…

  10. Creating a Family Health History

    MedlinePlus

    ... Health History? Click for more information A Family Tree for Health A family health history is a ... family members grew up. It's like a family tree for health. Click for more information What a ...

  11. Inventing the History of Invention.

    ERIC Educational Resources Information Center

    Molella, Arthur P.

    1988-01-01

    Selected are three pioneers who invented the history of technology: Abbott P. Usher, Lewis Mumford, and Sigfried Giedion. Their careers, publications, and contributions to the history of technology are described. (YP)

  12. Integrating Educational Theory and History

    ERIC Educational Resources Information Center

    Johnson, James P.

    1977-01-01

    Recommends that history teachers incorporate educational theory into their courses. Describes and evaluates a history course at Brooklyn College constructed around Benjamin Bloom's taxonomy of cognitive educational objectives. (Author/DB)

  13. Summary of The History Manifesto.

    PubMed

    Jacobs, Noortje

    2016-06-01

    This essay provides a brief, impartial summary of some main points of The History Manifesto, of the debate among historians that it has engendered, and of its connection to previous debates in and about the history of the sciences.

  14. Quantum histories without contrary inferences

    SciTech Connect

    Losada, Marcelo; Laura, Roberto

    2014-12-15

    In the consistent histories formulation of quantum theory it was shown that it is possible to retrodict contrary properties. We show that this problem do not appear in our formalism of generalized contexts for quantum histories. - Highlights: • We prove ordinary quantum mechanics has no contrary properties. • Contrary properties in consistent histories are reviewed. • We prove generalized contexts for quantum histories have no contrary properties.

  15. A Glimpse into History

    NASA Image and Video Library

    2016-11-09

    Nothing gets a geologist more excited than layered bedrock, except perhaps finding a fossil or holding a meteorite in your hand. All of these things create a profound feeling of history, the sense of a story that took place ages ago, long before we came appeared. Layered bedrock in particular tells a story that was set out chapter by chapter as each new layer was deposited on top of older, previously deposited layers. Here in Nili Fossae, we see layered bedrock as horizontal striations in the light toned sediments in the floor of a canyon near Syrtis Major. (Note: illumination is from the top of the picture) The ancient layered rocks appear in pale whitish and bluish tones. They are partially covered by much younger ripples made up of dust and other wind blown sediments. The rock of the nearby canyon wall is severely fractured and appears to have shed sand and rocks and boulders onto the floor. This canyon did not form by fluvial erosion: it is part of a system of faults that formed a series of graben like this one, but water probably flowed through Nili Fossae in the distant past. Orbital spectral measurements by the OMEGA instrument on Mars Express and CRISM on MRO detected an abundance of clay minerals of different types in the layered sediments inside Nili Fossae, along with other minerals that are typical of sediments that were deposited by water. The various colors and tones of the layered rocks record changes in the composition of the sediments, details that can tell us about changes in the Martian environment eons ago. Nili Fossae is a candidate site for a future landed robotic mission that could traverse across these layers and make measurements that could be used to unravel a part of the early history of Mars. Nili Fossae is a history book that is waiting to be read. http://photojournal.jpl.nasa.gov/catalog/PIA21206

  16. A history of salt.

    PubMed

    Cirillo, M; Capasso, G; Di Leo, V A; De Santo, N G

    1994-01-01

    The medical history of salt begins in ancient times and is closely related to different aspects of human history. Salt may be extracted from sea water, mineral deposits, surface encrustations, saline lakes and brine springs. In many inland areas, wood was used as a fuel source for evaporation of brine and this practice led to major deafforestation in central Europe. Salt played a central role in the economies of many regions, and is often reflected in place names. Salt was also used as a basis for population censuses and taxation, and salt monopolies were practised in many states. Salt was sometimes implicated in the outbreak of conflict, e.g. the French Revolution and the Indian War of Independence. Salt has also been invested with many cultural and religious meanings, from the ancient Egyptians to the Middle Ages. Man's innate appetite for salt may be related to his evolution from predominantly vegetarian anthropoids, and it is noteworthy that those people who live mainly on protein and milk or who drink salty water do not generally salt their food, whereas those who live mainly on vegetables, rice and cereals use much more salt. Medicinal use tended to emphasize the positive aspects of salt, e.g. prevention of putrefaction, reduction of tissue swelling, treatment of diarrhea. Evidence was also available to ancient peoples of its relationship to fertility, particularly in domestic animals. The history of salt thus represents a unique example for studying the impact of a widely used dietary substance on different important aspects of man's life, including medical philosophy.

  17. Local History in the Classroom.

    ERIC Educational Resources Information Center

    Labbett, B. D. C.

    1979-01-01

    Describes a curriculum development project developed in the United Kingdom to help students write histories based on local case studies. Topics discussed include reasons for writing local history, gathering historical evidence, primary source materials, procedures, and advantages of a local history project. (Author/DB)

  18. Make History with Your Students.

    ERIC Educational Resources Information Center

    Simon, Linda

    1992-01-01

    Presents creative ways for teachers to interest students in learning history by encouraging a feel for the context and interrelationships of events. Names, dates, and events are interspersed with opportunities for students to experience history through their own lives (e.g. oral histories, personal scrapbooks, family photographs, and household…

  19. United States History: United States History I, Honors United States History I ACT, AP US History I.

    ERIC Educational Resources Information Center

    Fort Worth Independent School District, TX.

    This curriculum guide, covering U.S. history, honors U.S. history, and advanced placement U.S. history contains the following components: a statement of philosophy and broad goals for each content area; objectives organized around broad content goals or strands; scope and sequence charts; instructional planning guides that include suggested…

  20. Build Skills by Doing History

    ERIC Educational Resources Information Center

    Monte-Sano, Chauncey

    2012-01-01

    No Child Left Behind has profoundly limited the teaching of history over the past 10 years. Now, the Common Core State Standards offers an opportunity to reverse this decline by giving history a more prominent place in the school curriculum alongside literacy goals. Learning history and argumentative writing is key to developing analytical ways of…

  1. Family Histories: Collecting, Connecting, Celebrating.

    ERIC Educational Resources Information Center

    Damkoehler, Dee; And Others

    1996-01-01

    Describes an integrated curriculum for grade two at Metcalf Laboratory School, Normal, Illinois, that celebrates family histories and American immigration. Reports that the journey begins with the teachers sharing their own family backgrounds, followed by story reading, sharing the family history project with parents, collecting oral histories,…

  2. Book History and Ideological Hierarchies

    ERIC Educational Resources Information Center

    Dilevko, Juris; Dali, Keren

    2006-01-01

    The evolving field of Book History has had difficulty in integrating the experiences of immigrant culture. In explaining the origins of print culture in North America, Book History has a tendency to associate lowbrow with immigrants and their struggles to establish a foothold in a new land. Book History therefore symbolically defines immigrant…

  3. William Faulkner as History Teacher

    ERIC Educational Resources Information Center

    Wright, C. Ben

    1976-01-01

    William Faulkner's novel "Absalom, Absalom!" is described as a valuable teaching resource for an introduction to the philosophy of history. At least six ways of viewing history are presented in the book, which is useful and motivating in helping students understand the complex nature of history. (AV)

  4. The End of Economic History?

    ERIC Educational Resources Information Center

    Romer, Christina D.

    1994-01-01

    Contends that the field of economic history is no longer a separate subfield of economics but an integral part of the entire discipline. Explains the concepts of monetary policy, labor force development, and economic growth in U.S. economic history. Concludes that the end of economic history is the beginning of better and richer economics. (CFR)

  5. Oral History: A Selective Bibliography.

    ERIC Educational Resources Information Center

    Kusnerz, Peggy Ann

    1979-01-01

    This selected bibliography lists 188 items pertaining to oral history, including manuals and handbooks, collection guides and directories, methods, interviewing techniques, theories, teaching devices, oral history in libraries and archives, international perspectives, oral history in research, the profession, and periodicals. (CHC)

  6. Recasting History: The Public Option

    ERIC Educational Resources Information Center

    Salerno, Beth

    2014-01-01

    If you ask Americans what is studied in history classrooms, many will answer "facts and dates." If you ask them what people can do with a history degree, they answer "teach." Yet those same Americans acknowledge the power and practical relevance of history as they flock to national parks, historic sites, museums, and cultural…

  7. Ethnic Groups in History Textbooks.

    ERIC Educational Resources Information Center

    Glazer, Nathan; Ueda, Reed

    Six popular high school American history textbooks are examined to address accusations of overcompensation by textbook publishers as a result of the raised ethnic consciousness of the 1970s. The textbooks are: "Our American Heritage" (Silver Burdett); "The Pageant of American History" (Allyn and Bacon); "A History of Our American Republic"…

  8. The End of Economic History?

    ERIC Educational Resources Information Center

    Romer, Christina D.

    1994-01-01

    Contends that the field of economic history is no longer a separate subfield of economics but an integral part of the entire discipline. Explains the concepts of monetary policy, labor force development, and economic growth in U.S. economic history. Concludes that the end of economic history is the beginning of better and richer economics. (CFR)

  9. The History of Wound Care

    PubMed Central

    Shah, Jayesh B.

    2012-01-01

    The history of wound healing is, in a sense, the history of humankind. This brief history of wound healing has been compiled for the benefit of readers. It is amazing to see that some of the basic principles of wound healing have been known since 2000 bc. PMID:24525756

  10. Save Our History: Our Documents.

    ERIC Educational Resources Information Center

    O'Connell, Libby Haight; Gordon, Sarah; Suisman, David

    2003-01-01

    The Fall 2003 Idea Book features: "Save Our History Study Guide: Our Documents"; "History International Study Guide: Pyramids"; "The History Channel Study Guide: Lewis and Clark" (Ideas from Our Teachers Contest Rules; Ideas from Our Teachers Context Winners); "A&E Classroom Study Guide: Post…

  11. Cultural History and Cultural Materialism.

    ERIC Educational Resources Information Center

    Berman, Ronald

    1990-01-01

    Historicism critiques cultural history and cultural materialism as a methodology for literary analysis. Questions the finality of interpretation, how original values change, and whether dramatic history implies actual history. Using Shakespearean plays, analyzes the power and politics of a play in relation to its audience; posits that cultural…

  12. History + Mystery = Inquiring Young Historians

    ERIC Educational Resources Information Center

    Kirchner, Jana; Helm, Allison; Pierce, Kristin; Galloway, Michele

    2011-01-01

    While social studies content about communities, neighborhood jobs, and maybe even some state history is taught in the early elementary grades, often the upper elementary grades are the first time students learn about the larger progression of history. How do teachers begin to teach the progression of U.S. history and the themes and questions that…

  13. Recasting History: The Public Option

    ERIC Educational Resources Information Center

    Salerno, Beth

    2014-01-01

    If you ask Americans what is studied in history classrooms, many will answer "facts and dates." If you ask them what people can do with a history degree, they answer "teach." Yet those same Americans acknowledge the power and practical relevance of history as they flock to national parks, historic sites, museums, and cultural…

  14. Lesson Study and History Education

    ERIC Educational Resources Information Center

    Halvorsen, Anne-Lise; Kesler Lund, Alisa

    2013-01-01

    This article examines the experiences of a group of fifth-grade teachers who used lesson study, a teacher-driven form of professional development, to teach history in a project supported by a Teaching American History Grant. The project addressed the following questions: What does a lesson study cycle for history education look like? What…

  15. Lesson Study and History Education

    ERIC Educational Resources Information Center

    Halvorsen, Anne-Lise; Kesler Lund, Alisa

    2013-01-01

    This article examines the experiences of a group of fifth-grade teachers who used lesson study, a teacher-driven form of professional development, to teach history in a project supported by a Teaching American History Grant. The project addressed the following questions: What does a lesson study cycle for history education look like? What…

  16. The Controversy around Black History.

    ERIC Educational Resources Information Center

    Pitre, Abul; Ray, Ruth

    2002-01-01

    Controversy over black history began in 1926, when Carter G. Woodson introduced Negro history week, and has continued into the 21st century. Proponents of black history believe it promotes diversity, develops self-esteem, and corrects myths and stereotypes. Opponents argue it is dishonest, divisive, and lacks academic credibility and rigor.…

  17. NEWE: A Western Shoshone History.

    ERIC Educational Resources Information Center

    Inter-Tribal Council of Nevada, Reno.

    One in a series of four histories of native Nevadans, this volume relates the history of the Western Shoshone, or Newe, whose territory included parts of the Great Basin area which extends from southern California to Idaho. Based on the spoken word of tribal elders and research conducted at numerous archives, the history begins with ancient…

  18. Book History and Ideological Hierarchies

    ERIC Educational Resources Information Center

    Dilevko, Juris; Dali, Keren

    2006-01-01

    The evolving field of Book History has had difficulty in integrating the experiences of immigrant culture. In explaining the origins of print culture in North America, Book History has a tendency to associate lowbrow with immigrants and their struggles to establish a foothold in a new land. Book History therefore symbolically defines immigrant…

  19. Make History with Your Students.

    ERIC Educational Resources Information Center

    Simon, Linda

    1992-01-01

    Presents creative ways for teachers to interest students in learning history by encouraging a feel for the context and interrelationships of events. Names, dates, and events are interspersed with opportunities for students to experience history through their own lives (e.g. oral histories, personal scrapbooks, family photographs, and household…

  20. Studying Russian and Soviet History.

    ERIC Educational Resources Information Center

    Ascher, Abraham, Ed.

    These essays were written to assist teachers in the task of making Russian history intelligible to young U.S. students. In "An Approach to Russian History," Edward Keenan proposes that students need to gain a better understanding of how Russians perceive themselves and their history. In "Pre-Petrine Russia," Andrzej S. Kaminski…

  1. Ethnic Groups in History Textbooks.

    ERIC Educational Resources Information Center

    Glazer, Nathan; Ueda, Reed

    Six popular high school American history textbooks are examined to address accusations of overcompensation by textbook publishers as a result of the raised ethnic consciousness of the 1970s. The textbooks are: "Our American Heritage" (Silver Burdett); "The Pageant of American History" (Allyn and Bacon); "A History of Our American Republic"…

  2. History + Mystery = Inquiring Young Historians

    ERIC Educational Resources Information Center

    Kirchner, Jana; Helm, Allison; Pierce, Kristin; Galloway, Michele

    2011-01-01

    While social studies content about communities, neighborhood jobs, and maybe even some state history is taught in the early elementary grades, often the upper elementary grades are the first time students learn about the larger progression of history. How do teachers begin to teach the progression of U.S. history and the themes and questions that…

  3. [History of hip arthroplasty].

    PubMed

    Płomiński, Janusz; Kwiatkowski, Krzysztof

    2007-02-01

    The authors present the history of hip prosthesis in treatment of coxarthrosis. Despite eighty years of experience the problem of gaining good and long-term results still exist and is difficult to solve. Even changing the way on cementless stabilization of prosthesis doesn't has result in solving the problem of aseptic loosening of hip arthroplasty. Problems of wear derbies made the producers find new to reduce particulate debris. The future of hip arthroplasty is connected with hip resurfacing. Moreover, the higher number of primary hip plasty the more prosthesis are loosening. The treatment is far more difficult and more expensive.

  4. The history of happiness.

    PubMed

    Stearns, Peter N

    2012-01-01

    In the 18th century, the Enlightenment ushered in the notion that happiness was the attainment of a worthy life. Since then the pursuit of happiness has spread to every aspect of behavior, from religion and politics to work and parenting. Today the happiness imperative creates pressures that, paradoxically, can make us miserable. Sadness is often mistaken for a pathology. Understanding the cultural commitment to good cheer as an artifact of modern history, not as an inherent feature of the human condition, opens new opportunities for understanding key facets of our social and personal experience.

  5. A History Worth Preserving

    NASA Astrophysics Data System (ADS)

    Kelly, Cynthia

    2008-04-01

    The Manhattan Project transformed the course of American and world history, science, politics and society. If we can read about this in books and watch History Channel documentaries, why do we need to preserve some of the properties of this enormous undertaking? The presentation, ``A History Worth Preserving,'' will address why some of the physical properties need to be preserved and which ones we are struggling to maintain for future generations. The story of this effort begins in 1997 as the Department of Energy was posed to demolish the last remaining Manhattan Project properties at the Los Alamos laboratory. Located deep behind security fences, the ``V Site's'' asbestos-shingled wooden buildings looked like humble garages with over-sized wooden doors. The ``V Site'' properties were almost lost twice, first to bulldozers and then the Cerro Grande fire of 2000. Now, visitors can stand inside the building where J. Robert Oppenheimer and his crew once worked and imagine the Trinity ``gadget'' hanging from its hoist shortly before it ushered in the Atomic Age on July 16, 1945. As Richard Rhodes has commented, we preserve what we value of the physical past because it specifically embodies our social past. But many challenge whether the Manhattan Project properties ought to be preserved. Rather than recognize the Manhattan Project as a great achievement worthy of commemoration, some see it as a regrettable event, producing an instrument to take man's inhumanity to man to extremes. While these divergent views will no doubt persist, the significance of the Manhattan Project in producing the world's first atomic bombs is irrefutable. Preserving some of its tangible remains is essential so that future generations can understand what the undertaking entailed from its humble wooden sheds to enormous first-of-a-kind industrial plants with 125,000 people working in secret and living in frontier-like communities. With continuing pressure for their demolition, what progress has

  6. Climate in Earth history

    NASA Technical Reports Server (NTRS)

    Berger, W. H.; Crowell, J. C.

    1982-01-01

    Complex atmosphere-ocean-land interactions govern the climate system and its variations. During the course of Earth history, nature has performed a large number of experiments involving climatic change; the geologic record contains much information regarding these experiments. This information should result in an increased understanding of the climate system, including climatic stability and factors that perturb climate. In addition, the paleoclimatic record has been demonstrated to be useful in interpreting the origin of important resources-petroleum, natural gas, coal, phosphate deposits, and many others.

  7. [History and epidemiology].

    PubMed

    Sánchez-Granjel, Mercedes; Benito González, F; Batuecas Caletrío, A

    2009-02-01

    The development of knowledge of paragangliomas has been inextricably linked to the development of all fields of medicine. Throughout history, both knowledge of diseases and technical improvements in diagnosis have served to understand these tumors, although unanswered questions remain. From the XVIII century to the XXI century events sometimes unexpected and other times intensely sought have occurred that have helped to identify the characteristics of these tumors. These events have ranged from description of paragangliomas to their genetic diagnosis. The incidence of paragangliomas is not high. Nevertheless, the variability of these tumors in terms of their localization, forms of presentation, possibilities of metastasis or their hereditary component has been well characterized.

  8. Atmospheric refraction: a history

    NASA Astrophysics Data System (ADS)

    Lehn, Waldemar H.; van der Werf, Siebren

    2005-09-01

    We trace the history of atmospheric refraction from the ancient Greeks up to the time of Kepler. The concept that the atmosphere could refract light entered Western science in the second century B.C. Ptolemy, 300 years later, produced the first clearly defined atmospheric model, containing air of uniform density up to a sharp upper transition to the ether, at which the refraction occurred. Alhazen and Witelo transmitted his knowledge to medieval Europe. The first accurate measurements were made by Tycho Brahe in the 16th century. Finally, Kepler, who was aware of unusually strong refractions, used the Ptolemaic model to explain the first documented and recognized mirage (the Novaya Zemlya effect).

  9. Earthquake history of Oregon

    USGS Publications Warehouse

    von Hake, C. A.

    1976-01-01

    Although situated between two States (California and Washington) that have has many violent earthquakes, Oregon is noticeably less active seismically. the greatest damage experienced resulted from a major shock near Olympia, Wash., in 1949. During the short history record available (since 1841), 34 earthquakes of intensity V, Modified Mercalli Scale, or greater have centered within Oregon or near its borders. Only 13 of the earthquakes had an intensity above V, and many of the shocks were local. However, a 1936 earthquake in the eastern Oregon-Washington region caused extensive damage and was felt over an area of 272,000 square kilometers. 

  10. History of Kawasaki disease.

    PubMed

    Kawasaki, Tomisaku; Naoe, Shiro

    2014-04-01

    We describe a short history of Kawasaki disease. In 1967, we published a paper entitled 'Infantile acute febrile mucocutaneous lymph node syndrome with specific desquamation of the fingers and toes. Clinical observation of 50 cases'; this was the first report on what is now called Kawasaki disease. Since then, many reports on cardiology, treatment, epidemiology, pathology and etiology of Kawasaki disease have been published. Furthermore, a recent Chapel Hill Consensus Statement on Kawasaki disease in the classification of vasculitis is given, along with a figure on the relationship and classification of childhood vasculitis by autopsy material.

  11. History of gluteal augmentation.

    PubMed

    de la Peña, J Abel; Rubio, Omar V; Cano, Jacobo P; Cedillo, Mariana C; Garcés, Miriam T

    2006-07-01

    The concept of female beauty has changed throughout time, but the form and size of the breasts and gluteal region have remained constant as symbols of maximum femininity. Sculptures and prints show us feminine figures that are voluminous and reflect human history's interest in fertility. The early years of gluteal augmentation saw few published reports that described the procedure technique, follow-up, or possible complications. But developments continued as surgeons began experimenting with different anatomical planes for implant placement. The most important goal in plastic surgery is meeting a patient's expectations. It is important for the surgeon to thoroughly explain to patients what can realistically be achieved with a procedure.

  12. Atmospheric refraction: a history.

    PubMed

    Lehn, Waldemar H; van der Werf, Siebren

    2005-09-20

    We trace the history of atmospheric refraction from the ancient Greeks up to the time of Kepler. The concept that the atmosphere could refract light entered Western science in the second century B.C. Ptolemy, 300 years later, produced the first clearly defined atmospheric model, containing air of uniform density up to a sharp upper transition to the ether, at which the refraction occurred. Alhazen and Witelo transmitted his knowledge to medieval Europe. The first accurate measurements were made by Tycho Brahe in the 16th century. Finally, Kepler, who was aware of unusually strong refractions, used the Ptolemaic model to explain the first documented and recognized mirage (the Novaya Zemlya effect).

  13. History of robotic surgery.

    PubMed

    Kalan, Satyam; Chauhan, Sanket; Coelho, Rafael F; Orvieto, Marcelo A; Camacho, Ignacio R; Palmer, Kenneth J; Patel, Vipul R

    2010-09-01

    Robotic surgery is one of the most advanced forms of Minimally Invasive Surgery. Although the application of robotic technology to surgical robotics started some 20 years ago, the earliest work in robotics and automation can be traced back to 400 BC. Some of the early pioneers include Archytas of Arentum, Leonardo da Vinci, Gianello Toriano, and Pierre Jaquet-Droz, and we owe to these philosophers and scientists the fact that we can offer the benefit of minimal invasion in surgery. The purpose of this review is to give a brief description of the evolution of robotic surgery from its early history to present-day surgical robotics.

  14. The history of autism.

    PubMed

    Wolff, Sula

    2004-08-01

    Autism remains a fascinating condition, perhaps the most prolifically researched of all child psychiatric disorders. Its history yields many lessons: early accounts of possible autism are, with one exception, unclear; the greatest contributions to our understanding have come from individual clinicians and researchers; the concept and definition of the disorder have changed greatly over the years; some ideas once held with conviction, were later proved to be unfounded; and socio-political shifts as well as research findings have radically altered our understanding of the syndrome as well as the care and treatment offered to people with autism.

  15. History of rhinoplasty.

    PubMed

    Belinfante, Louis S

    2012-02-01

    Man has considered the nose to be a key feature, if not the key feature, of facial appearance, beauty, and dynamics. However, because of its central facial location and weak cartilaginous support, the nose is susceptible to disfiguring infection, trauma, pathologic entities, and human-associated carnages. This article discusses the various methods (eg, endonasal approach, external approach, and osteoplastic operations) surgeons have tried throughout history to give their patients a more attractive face by altering the one physical anatomic structure that one usually notices first.

  16. Anthropology and history: the revaluation of history in anthropological research.

    PubMed

    Colić, S

    1999-12-01

    The main premise of this paper is that the accepted view of history based on written documents (historiography) is marked by hierarchical ordering and evaluation implicit in it. The paper examines the context of the negation of history, and the revaluation of history in anthropological research. The lack of written documents concerning particular social groups on the internal plane, but also particular nations (ethnic groups) on the global plane, earned them the name of "nations (groups) without history". This criterion of historicity--the existence of a writing system and written documents--implies the hypothesis about the inferiority of those nations and groups. The attributes of history seen in this way are modernity, linearity and cumulativeness. This system implies ethnocentrism based on a twofold negation: a) the negation history, and b) the negation of otherness. What we must not forget is that the symbolic universes are social products with a history, and in order to understand their meaning, one must understand the history of their production. It is very important to pay close attention to the historical practice of projecting our cultural practices onto others. The question of who determines the history and which views are presented to a particular audience is a matter of power and contest. contemporary history-oriented sociocultural anthropology focuses on the total reconstruction of the way of life and thinking in particular periods of history: on the everyday life. This brought together the intellectual traditions of "new history", ethnology, sociocultural anthropology and the sociology of culture. While modernism stresses the present change versus the static past, postmodernism denies the past ever being static and hypostatises fluidity and change as permanent condition. Postmodernism strives to undermine the old, Euro-centric notion that "we" have a history but "they" do not; it has also lead to social scientists' renewed interest in history.

  17. Panic attack history and smoking topography.

    PubMed

    Farris, Samantha G; Brown, Lily A; Goodwin, Renee D; Zvolensky, Michael J

    2017-02-01

    Little is known about panic attacks and puffing topography, a behavioral index of the value of smoking reinforcement. This study examined smoking style during the course of smoking of a single cigarette among adult daily smokers with and without a history of panic attacks. Participants (n=124, Mage=43.9, SD=9.7; 44.4% female) were non-treatment seeking daily smokers. Lifetime panic attack history was assessed via diagnostic assessment; 28.2% (n=35) of the sample had a panic attack history. Participants smoked one cigarette during an ad libitum smoking trial. Puff volume, duration, and inter-puff interval were measured using the Clinical Research Support System (CReSS) pocket device. Regression analyses revealed that panic attack status was not associated with significant differences in average puff volume, duration, or inter-puff interval. Multi-level modeling was used to examine puffing trajectories. Puff-level data revealed that there was a significant quadratic time x panic effect for puff volume and duration. Those with a panic attack history demonstrated relatively sustained levels of both puff volume and duration over time, whereas those without a history of panic attacks demonstrated an increase followed by a decrease in volume and duration over time. These effects were not accounted for by the presence of general psychopathology. Smokers with a panic attack history demonstrate more persistent efforts to self-regulate the delivery of nicotine, and thus may be at risk for continued smoking and dependence. Tailored treatment may be needed to address unique vulnerabilities among this group. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. History of Human Parasitology

    PubMed Central

    Cox, F. E. G.

    2002-01-01

    Humans are hosts to nearly 300 species of parasitic worms and over 70 species of protozoa, some derived from our primate ancestors and some acquired from the animals we have domesticated or come in contact with during our relatively short history on Earth. Our knowledge of parasitic infections extends into antiquity, and descriptions of parasites and parasitic infections are found in the earliest writings and have been confirmed by the finding of parasites in archaeological material. The systematic study of parasites began with the rejection of the theory of spontaneous generation and the promulgation of the germ theory. Thereafter, the history of human parasitology proceeded along two lines, the discovery of a parasite and its subsequent association with disease and the recognition of a disease and the subsequent discovery that it was caused by a parasite. This review is concerned with the major helminth and protozoan infections of humans: ascariasis, trichinosis, strongyloidiasis, dracunculiasis, lymphatic filariasis, loasis, onchocerciasis, schistosomiasis, cestodiasis, paragonimiasis, clonorchiasis, opisthorchiasis, amoebiasis, giardiasis, African trypanosomiasis, South American trypanosomiasis, leishmaniasis, malaria, toxoplasmosis, cryptosporidiosis, cyclosporiasis, and microsporidiosis. PMID:12364371

  19. History of ball bearings

    NASA Technical Reports Server (NTRS)

    Dowson, D.; Hamrock, B. J.

    1981-01-01

    The familiar precision rolling-element bearings of the twentieth century are products of exacting technology and sophisticated science. Their very effectiveness and basic simplicity of form may discourage further interest in their history and development. Yet the full story covers a large portion of recorded history and surprising evidence of an early recognition of the advantages of rolling motion over sliding action and progress toward the development of rolling-element bearings. The development of rolling-element bearings is followed from the earliest civilizations to the end of the eighteenth century. The influence of general technological developments, particularly those concerned with the movement of large building blocks, road transportation, instruments, water-raising equipment, and windmills are discussed, together with the emergence of studies of the nature of rolling friction and the impact of economic factors. By 1800 the essential features of ball and rolling-element bearings had emerged and it only remained for precision manufacture and mass production to confirm the value of these fascinating machine elements.

  20. Zebra mussel life history

    SciTech Connect

    Ackerman, J.D.

    1995-06-01

    The success of introduced zebra mussels (Dreissena polymorpha (Pallas) and Dreissena bugensis Andrusova) can be related in large parttot a life history that is unlike that of the indigenous freshwater fauna and yet is conserved with marine bivalves. Following external fertilization and embryological development, there is a brief trochophore stage. With the development of a velum and the secretion of a D-shaped larval shell, the larva becomes a D-shaped veliger, which is the first recognizable planktonic larva. Later, the secretion of a second larval shell leads to the last obligate free-swimming veliger stage known as the veliconcha. The last larval stage known as the pediveliger, however, can both swim using its velum or crawl using its fully-functional foot. Pediveligers actively select substrates on which they {open_quotes}settle{close_quotes} by secreting byssal threads and undergo metamorphosis to become plantigrade mussels. The secretion of the adult shell and concomitant changes in growth axis leads to the heteromyariant or mussel-like shape, which is convergent with marine mussels. Like a number of other bivalves, zebra mussels produce byssal threads as adults, but these attachments may be broken enabling their translocation to new areas. The recognition and examination of these life history traits will lead to a better understanding of zebra mussel biology.