NASA Technical Reports Server (NTRS)
Gates, Thomas S.
1992-01-01
In order to understand matrix dominated behavior in laminated polymer matrix composites, an elastic/viscoplastic constitutive model was developed and used to predict stress strain behavior of off-axis and angle-ply symmetric laminates under in-plane, tensile axial loading. The model was validated for short duration tests at elevated temperatures. Short term stress relaxation and short term creep, strain rate sensitivity, and material nonlinearity were accounted for. The testing times were extended for longer durations, and periods of creep and stress relaxation were used to investigate the ability of the model to account for long term behavior. The model generally underestimated the total change in strain and stress for both long term creep and long term relaxation respectively.
ERIC Educational Resources Information Center
Hekler, Eric B.; Buman, Matthew P.; Poothakandiyil, Nikhil; Rivera, Daniel E.; Dzierzewski, Joseph M.; Aiken Morgan, Adrienne; McCrae, Christina S.; Roberts, Beverly L.; Marsiske, Michael; Giacobbi, Peter R., Jr.
2013-01-01
Efficacious interventions to promote long-term maintenance of physical activity are not well understood. Engineers have developed methods to create dynamical system models for modeling idiographic (i.e., within-person) relationships within systems. In behavioral research, dynamical systems modeling may assist in decomposing intervention effects…
Attractor learning in synchronized chaotic systems in the presence of unresolved scales
NASA Astrophysics Data System (ADS)
Wiegerinck, W.; Selten, F. M.
2017-12-01
Recently, supermodels consisting of an ensemble of interacting models, synchronizing on a common solution, have been proposed as an alternative to the common non-interactive multi-model ensembles in order to improve climate predictions. The connection terms in the interacting ensemble are to be optimized based on the data. The supermodel approach has been successfully demonstrated in a number of simulation experiments with an assumed ground truth and a set of good, but imperfect models. The supermodels were optimized with respect to their short-term prediction error. Nevertheless, they produced long-term climatological behavior that was close to the long-term behavior of the assumed ground truth, even in cases where the long-term behavior of the imperfect models was very different. In these supermodel experiments, however, a perfect model class scenario was assumed, in which the ground truth and imperfect models belong to the same model class and only differ in parameter setting. In this paper, we consider the imperfect model class scenario, in which the ground truth model class is more complex than the model class of imperfect models due to unresolved scales. We perform two supermodel experiments in two toy problems. The first one consists of a chaotically driven Lorenz 63 oscillator ground truth and two Lorenz 63 oscillators with constant forcings as imperfect models. The second one is more realistic and consists of a global atmosphere model as ground truth and imperfect models that have perturbed parameters and reduced spatial resolution. In both problems, we find that supermodel optimization with respect to short-term prediction error can lead to a long-term climatological behavior that is worse than that of the imperfect models. However, we also show that attractor learning can remedy this problem, leading to supermodels with long-term behavior superior to the imperfect models.
A phenomenological memristor model for short-term/long-term memory
NASA Astrophysics Data System (ADS)
Chen, Ling; Li, Chuandong; Huang, Tingwen; Ahmad, Hafiz Gulfam; Chen, Yiran
2014-08-01
Memristor is considered to be a natural electrical synapse because of its distinct memory property and nanoscale. In recent years, more and more similar behaviors are observed between memristors and biological synapse, e.g., short-term memory (STM) and long-term memory (LTM). The traditional mathematical models are unable to capture the new emerging behaviors. In this article, an updated phenomenological model based on the model of the Hewlett-Packard (HP) Labs has been proposed to capture such new behaviors. The new dynamical memristor model with an improved ion diffusion term can emulate the synapse behavior with forgetting effect, and exhibit the transformation between the STM and the LTM. Further, this model can be used in building new type of neural networks with forgetting ability like biological systems, and it is verified by our experiment with Hopfield neural network.
Applying Psychological Theories to Promote Long-Term Maintenance of Health Behaviors
Joseph, Rodney P.; Daniel, Casey L.; Thind, Herpreet; Benitez, Tanya J.; Pekmezi, Dori
2014-01-01
Behavioral health theory provides a framework for researchers to design, implement, and evaluate the effects of health promotion programs. However, limited research has examined theories used in interventions to promote long-term maintenance of health behaviors. The purpose of this review was to evaluate the available literature and identify prominent behavioral health theories used in intervention research to promote maintenance of health behaviors. We reviewed theories used in intervention research assessing long-term maintenance (≥ 6 months post-intervention) of physical activity, weight loss, and smoking cessation. Five prominent behavioral theories were referenced by the 34 studies included in the review: Self-Determination Theory, Theory of Planned Behavior, Social Cognitive Theory, Transtheoretical Model, and Social Ecological Model. Descriptions and examples of applications of these theories are provided. Implications for future research are discussed. PMID:28217036
Personalized query suggestion based on user behavior
NASA Astrophysics Data System (ADS)
Chen, Wanyu; Hao, Zepeng; Shao, Taihua; Chen, Honghui
Query suggestions help users refine their queries after they input an initial query. Previous work mainly concentrated on similarity-based and context-based query suggestion approaches. However, models that focus on adapting to a specific user (personalization) can help to improve the probability of the user being satisfied. In this paper, we propose a personalized query suggestion model based on users’ search behavior (UB model), where we inject relevance between queries and users’ search behavior into a basic probabilistic model. For the relevance between queries, we consider their semantical similarity and co-occurrence which indicates the behavior information from other users in web search. Regarding the current user’s preference to a query, we combine the user’s short-term and long-term search behavior in a linear fashion and deal with the data sparse problem with Bayesian probabilistic matrix factorization (BPMF). In particular, we also investigate the impact of different personalization strategies (the combination of the user’s short-term and long-term search behavior) on the performance of query suggestion reranking. We quantify the improvement of our proposed UB model against a state-of-the-art baseline using the public AOL query logs and show that it beats the baseline in terms of metrics used in query suggestion reranking. The experimental results show that: (i) for personalized ranking, users’ behavioral information helps to improve query suggestion effectiveness; and (ii) given a query, merging information inferred from the short-term and long-term search behavior of a particular user can result in a better performance than both plain approaches.
Linking agent-based models and stochastic models of financial markets
Feng, Ling; Li, Baowen; Podobnik, Boris; Preis, Tobias; Stanley, H. Eugene
2012-01-01
It is well-known that financial asset returns exhibit fat-tailed distributions and long-term memory. These empirical features are the main objectives of modeling efforts using (i) stochastic processes to quantitatively reproduce these features and (ii) agent-based simulations to understand the underlying microscopic interactions. After reviewing selected empirical and theoretical evidence documenting the behavior of traders, we construct an agent-based model to quantitatively demonstrate that “fat” tails in return distributions arise when traders share similar technical trading strategies and decisions. Extending our behavioral model to a stochastic model, we derive and explain a set of quantitative scaling relations of long-term memory from the empirical behavior of individual market participants. Our analysis provides a behavioral interpretation of the long-term memory of absolute and squared price returns: They are directly linked to the way investors evaluate their investments by applying technical strategies at different investment horizons, and this quantitative relationship is in agreement with empirical findings. Our approach provides a possible behavioral explanation for stochastic models for financial systems in general and provides a method to parameterize such models from market data rather than from statistical fitting. PMID:22586086
Linking agent-based models and stochastic models of financial markets.
Feng, Ling; Li, Baowen; Podobnik, Boris; Preis, Tobias; Stanley, H Eugene
2012-05-29
It is well-known that financial asset returns exhibit fat-tailed distributions and long-term memory. These empirical features are the main objectives of modeling efforts using (i) stochastic processes to quantitatively reproduce these features and (ii) agent-based simulations to understand the underlying microscopic interactions. After reviewing selected empirical and theoretical evidence documenting the behavior of traders, we construct an agent-based model to quantitatively demonstrate that "fat" tails in return distributions arise when traders share similar technical trading strategies and decisions. Extending our behavioral model to a stochastic model, we derive and explain a set of quantitative scaling relations of long-term memory from the empirical behavior of individual market participants. Our analysis provides a behavioral interpretation of the long-term memory of absolute and squared price returns: They are directly linked to the way investors evaluate their investments by applying technical strategies at different investment horizons, and this quantitative relationship is in agreement with empirical findings. Our approach provides a possible behavioral explanation for stochastic models for financial systems in general and provides a method to parameterize such models from market data rather than from statistical fitting.
Wasserkampf, A; Silva, M N; Santos, I C; Carraça, E V; Meis, J J M; Kremers, S P J; Teixeira, P J
2014-12-01
This study analyzed psychosocial predictors of the Theory of Planned Behavior (TPB) and Self-Determination Theory (SDT) and evaluated their associations with short- and long-term moderate plus vigorous physical activity (MVPA) and lifestyle physical activity (PA) outcomes in women who underwent a weight-management program. 221 participants (age 37.6 ± 7.02 years) completed a 12-month SDT-based lifestyle intervention and were followed-up for 24 months. Multiple linear regression analyses tested associations between psychosocial variables and self-reported short- and long-term PA outcomes. Regression analyses showed that control constructs of both theories were significant determinants of short- and long-term MVPA, whereas affective and self-determination variables were strong predictors of short- and long-term lifestyle PA. Regarding short-term prediction models, TPB constructs were stronger in predicting MVPA, whereas SDT was more effective in predicting lifestyle PA. For long-term models, both forms of PA were better predicted by SDT in comparison to TPB. These results highlight the importance of comparing health behavior theories to identify the mechanisms involved in the behavior change process. Control and competence constructs are crucial during early adoption of structured PA behaviors, whereas affective and intrinsic sources of motivation are more involved in incidental types of PA, particularly in relation to behavioral maintenance. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Remembering the Past and Imagining the Future: A Neural Model of Spatial Memory and Imagery
ERIC Educational Resources Information Center
Byrne, Patrick; Becker, Suzanna; Burgess, Neil
2007-01-01
The authors model the neural mechanisms underlying spatial cognition, integrating neuronal systems and behavioral data, and address the relationships between long-term memory, short-term memory, and imagery, and between egocentric and allocentric and visual and ideothetic representations. Long-term spatial memory is modeled as attractor dynamics…
Long-term effects of child punishment on Mexican women: a structural model.
Frias-Armenta, Martha
2002-04-01
The aim of this study was to investigate long-term effects of parental use of physical and verbal punishment on Mexican women. To study both direct and indirect effects of these phenomena, a structural model was developed and tested. One hundred and fifty Mexican women were interviewed with regard to their history of child abuse, their level of depression, alcohol use, antisocial behavior, and punishment of their own children. Factors representing such constructs were specified within a structural equation model and their inter-relations were estimated. Women's history of abuse was considered as an exogenous latent variable directly affecting three other factors: mothers' antisocial behavior, their alcohol consumption, and their levels of depression or anxiety. These factors, in turn, were specified as influencing mothers' harsh discipline of their own children. Data supported this model, indicating that a history of abuse has long-term effects on women's behavior and psychological functioning, which in turn cause women's punitive behavior against their children. These results are discussed in terms of the theoretical framework of intergenerational transmission of violence. The direct consequences (depression, anxiety, alcohol consumption, and antisocial behavior) of child punishment act as risk factors for the next generation of child abuse.
Automatic Screening for Perturbations in Boolean Networks.
Schwab, Julian D; Kestler, Hans A
2018-01-01
A common approach to address biological questions in systems biology is to simulate regulatory mechanisms using dynamic models. Among others, Boolean networks can be used to model the dynamics of regulatory processes in biology. Boolean network models allow simulating the qualitative behavior of the modeled processes. A central objective in the simulation of Boolean networks is the computation of their long-term behavior-so-called attractors. These attractors are of special interest as they can often be linked to biologically relevant behaviors. Changing internal and external conditions can influence the long-term behavior of the Boolean network model. Perturbation of a Boolean network by stripping a component of the system or simulating a surplus of another element can lead to different attractors. Apparently, the number of possible perturbations and combinations of perturbations increases exponentially with the size of the network. Manually screening a set of possible components for combinations that have a desired effect on the long-term behavior can be very time consuming if not impossible. We developed a method to automatically screen for perturbations that lead to a user-specified change in the network's functioning. This method is implemented in the visual simulation framework ViSiBool utilizing satisfiability (SAT) solvers for fast exhaustive attractor search.
Time-series modeling of long-term weight self-monitoring data.
Helander, Elina; Pavel, Misha; Jimison, Holly; Korhonen, Ilkka
2015-08-01
Long-term self-monitoring of weight is beneficial for weight maintenance, especially after weight loss. Connected weight scales accumulate time series information over long term and hence enable time series analysis of the data. The analysis can reveal individual patterns, provide more sensitive detection of significant weight trends, and enable more accurate and timely prediction of weight outcomes. However, long term self-weighing data has several challenges which complicate the analysis. Especially, irregular sampling, missing data, and existence of periodic (e.g. diurnal and weekly) patterns are common. In this study, we apply time series modeling approach on daily weight time series from two individuals and describe information that can be extracted from this kind of data. We study the properties of weight time series data, missing data and its link to individuals behavior, periodic patterns and weight series segmentation. Being able to understand behavior through weight data and give relevant feedback is desired to lead to positive intervention on health behaviors.
Spence, Nicholas D; Newton, Amanda S; Keaschuk, Rachel A; Ambler, Kathryn A; Jetha, Mary M; Holt, Nicholas L; Rosychuk, Rhonda J; Spence, John C; Sharma, Arya M; Ball, Geoff D C
Attrition in pediatric weight management is a substantial problem. This study examined factors associated with short- and long-term attrition from a lifestyle and behavioral intervention for parents of children with overweight or obesity. Fifty-two families with children ages 6 to 12 years old and body mass index at or above the 85th percentile participated in a randomized controlled trial focused on parents, comparing parent-based cognitive behavioral therapy with parent-based psychoeducation for pediatric weight management. We examined program attrition using two clinical phases of the intervention: short-term and long-term attrition, modeled using the general linear model. Predictors included intervention type, child/parent weight status, sociodemographic factors, and health of the family system. Higher self-assessed health of the family system was associated with lower short-term attrition; higher percentage of intervention sessions attended by parents was associated with lower long-term attrition. Different variables were significant in our short- and long-term models. Attrition might best be conceptualized based on short- and long-term phases of clinical, parent-based interventions for pediatric weight management. Copyright © 2016 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.
Bales, Karen L.; Perkeybile, Allison M.; Conley, Olivia G.; Lee, Meredith H.; Guoynes, Caleigh D.; Downing, Griffin M.; Yun, Catherine R.; Solomon, Marjorie; Jacob, Suma; Mendoza, Sally P.
2012-01-01
Background Oxytocin (OT) is a hormone shown to be involved in social bonding in animal models. Intranasal OT is currently in clinical trials for use in disorders such as autism and schizophrenia. We examined long-term effects of intranasal OT given developmentally in the prairie vole (Microtus ochrogaster), a socially monogamous rodent, often used as an animal model to screen drugs that have therapeutic potential for social disorders. Methods We treated voles with one of three dosages of intranasal OT, or saline, from day 21 (weaning) through day 42 (sexual maturity). We examined both social behavior immediately following administration, as well as long-term changes in social and anxiety behavior after treatment ceased. Group sizes varied from 8 to 15 voles (n = 89 voles total). Results Treatment with OT resulted in acute increases in social behavior in males with familiar partners, as seen in humans. However, long-term developmental treatment with low doses of intranasal OT resulted in a deficit in partner preference behavior (a reduction of contact with a familiar opposite-sex partner, used to index pair-bond formation) by males. Conclusions Long-term developmental treatment with OT may show results different to those predicted by short-term studies, as well as significant sex differences and dosage effects. Further animal study is crucial to determining safe and effective strategies for use of chronic intranasal OT, especially during development. PMID:23079235
NASA Astrophysics Data System (ADS)
Sawada, Masataka; Nishimoto, Soshi; Okada, Tetsuji
2017-01-01
In high-level radioactive waste disposal repositories, there are long-term complex thermal, hydraulic, and mechanical (T-H-M) phenomena that involve the generation of heat from the waste, the infiltration of ground water, and swelling of the bentonite buffer. The ability to model such coupled phenomena is of particular importance to the repository design and assessments of its safety. We have developed a T-H-M-coupled analysis program that evaluates the long-term behavior around the repository (called "near-field"). We have also conducted centrifugal model tests that model the long-term T-H-M-coupled behavior in the near-field. In this study, we conduct H-M-coupled numerical simulations of the centrifugal near-field model tests. We compare numerical results with each other and with results obtained from the centrifugal model tests. From the comparison, we deduce that: (1) in the numerical simulation, water infiltration in the rock mass was in agreement with the experimental observation. (2) The constant-stress boundary condition in the centrifugal model tests may cause a larger expansion of the rock mass than in the in situ condition, but the mechanical boundary condition did not affect the buffer behavior in the deposition hole. (3) The numerical simulation broadly reproduced the measured bentonite pressure and the overpack displacement, but did not reproduce the decreasing trend of the bentonite pressure after 100 equivalent years. This indicates the effect of the time-dependent characteristics of the surrounding rock mass. Further investigations are needed to determine the effect of initial heterogeneity in the deposition hole and the time-dependent behavior of the surrounding rock mass.
Reconciling long-term cultural diversity and short-term collective social behavior.
Valori, Luca; Picciolo, Francesco; Allansdottir, Agnes; Garlaschelli, Diego
2012-01-24
An outstanding open problem is whether collective social phenomena occurring over short timescales can systematically reduce cultural heterogeneity in the long run, and whether offline and online human interactions contribute differently to the process. Theoretical models suggest that short-term collective behavior and long-term cultural diversity are mutually excluding, since they require very different levels of social influence. The latter jointly depends on two factors: the topology of the underlying social network and the overlap between individuals in multidimensional cultural space. However, while the empirical properties of social networks are intensively studied, little is known about the large-scale organization of real societies in cultural space, so that random input specifications are necessarily used in models. Here we use a large dataset to perform a high-dimensional analysis of the scientific beliefs of thousands of Europeans. We find that interopinion correlations determine a nontrivial ultrametric hierarchy of individuals in cultural space. When empirical data are used as inputs in models, ultrametricity has strong and counterintuitive effects. On short timescales, it facilitates a symmetry-breaking phase transition triggering coordinated social behavior. On long timescales, it suppresses cultural convergence by restricting it within disjoint groups. Moreover, ultrametricity implies that these results are surprisingly robust to modifications of the dynamical rules considered. Thus the empirical distribution of individuals in cultural space appears to systematically optimize the coexistence of short-term collective behavior and long-term cultural diversity, which can be realized simultaneously for the same moderate level of mutual influence in a diverse range of online and offline settings.
Stirling engine - Approach for long-term durability assessment
NASA Technical Reports Server (NTRS)
Tong, Michael T.; Bartolotta, Paul A.; Halford, Gary R.; Freed, Alan D.
1992-01-01
The approach employed by NASA Lewis for the long-term durability assessment of the Stirling engine hot-section components is summarized. The approach consists of: preliminary structural assessment; development of a viscoplastic constitutive model to accurately determine material behavior under high-temperature thermomechanical loads; an experimental program to characterize material constants for the viscoplastic constitutive model; finite-element thermal analysis and structural analysis using a viscoplastic constitutive model to obtain stress/strain/temperature at the critical location of the hot-section components for life assessment; and development of a life prediction model applicable for long-term durability assessment at high temperatures. The approach should aid in the provision of long-term structural durability and reliability of Stirling engines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daemen, Jaak J.K.; Ma, Lumin; Zhao, Guohua
The study of the long term mechanical behavior of Yucca Mountain tuffs is important for several reasons. Long term stability of excavations will affect accessibility (e.g. for inspection purposes), and retrievability. Long term instabilities may induce loading of drip shields and/or emplaced waste, thus affecting drip shield and/or waste package corrosion. Failure of excavations will affect airflow, may affect water flow, and may affect temperature distributions. The long term mechanical behavior of rocks remains an elusive topic, loaded with uncertainties. A variety of approaches have been used to improve the understanding of this complex subject, but it is doubtful thatmore » it has reached a stage where firm predictions can be considered feasible. The long term mechanical behavior of "soft" rocks, especially evaporites, and in particular rock salt, has been the subject of numerous investigations (e.g. Cristescu and Hunsche, 1998, Cristescu et al, 2002), and basic approaches towards engineering taking into account the long term behavior of such materials have long been well established (e.g. Dreyer, 1972, 1982). The same is certainly not true of "hard" rocks. While it long has been recognized that the long term strength of ?hard? rocks almost certainly is significantly less than that measured during "short", i.e. standard (ASTM D 2938), ISRM suggested (Bieniawski et al, 1978) and conventionally used test procedures (e.g. Bieniawski, 1970, Wawersik, 1972, Hoek and Brown, 1980, p. 150), what limited approaches have been taken to develop strategies toward determining the long term mechanical behavior of "hard" rock remain in the early research and investigation stage, at best. One early model developed specifically for time dependent analysis of underground "hard" rock structures is the phenomenological model by Kaiser and Morgenstern (1981). Brady and Brown (1985, p. 93) state that over a wide range of strain rates, from 10^-8 to 10^2/s the difference in strength is only a factor of 2, and that "the observed behavior of rock is not significantly influenced by varying the strain rate within the range that is convenient to use in quasi-static laboratory compression tests." While this is undoubtedly true, it does not really address the question as to whether or not strengths thus measured can be considered appropriate for estimating long term strengths. One objective of this investigation was to evaluate the applicability of the approaches by Cruden (e.g. Cruden, 1971, 1974, 1983, 1987) and by Lajtai (e.g. Lajtai and Schmidtke, 1986, 1987) to the prediction of the long term mechanical behavior of the investigated tuffs. This involves in particular static fatigue testing, by conducting uniaxial, triaxial, and indirect splitting (Brazilian) tests over a wide range of strain (or stress, or displacement) rates.« less
Short- and long-term antidepressant effects of ketamine in a rat chronic unpredictable stress model.
Jiang, Yinghong; Wang, Yiqiang; Sun, Xiaoran; Lian, Bo; Sun, Hongwei; Wang, Gang; Du, Zhongde; Li, Qi; Sun, Lin
2017-08-01
This research was aimed to evaluate the behaviors of short- or long-term antidepressant effects of ketamine in rats exposed to chronic unpredictable stress (CUS). Ketamine, a glutamate noncompetitive NMDA receptor antagonist, regulates excitatory amino acid functions, such as anxiety disorders and major depression, and plays an important role in synaptic plasticity and learning and memory. After 42 days of CUS model, male rats received either a single injection of ketamine (10 mg/kg; day 43) or 15 daily injections (days 43-75). The influence of ketamine on behavioral reactivity was assessed 24 hr (short-term) or 7 weeks after ketamine treatment (long-term). Behavioral tests used to assess the effects of these treatments included the sucrose preference (SP), open field (OF), elevated plus maze (EPM), forced swimming (FS), and water maze (WM) to detect anxiety-like behavior (OF and EPM), forced swimming (FS), and water maze (WM). Results: Short-term ketamine administration resulted in increases of body weight gain, higher sensitivity to sucrose, augmented locomotor activity in the OF, more entries into the open arms of the EPM, along increased activity in the FS test; all responses indicative of reductions in depression/despair in anxiety-eliciting situations. No significant differences in these behaviors were obtained under conditions of long-term ketamine administration ( p > .05). The CUS + Ketamine group showed significantly increased activity as compared with the CUS + Vehicle group for analysis of the long-term effects of ketamine (* p < .05). Nor were significant differences obtained in learning and memory performance in rats receiving ketamine ( p > .05). Taken together these findings demonstrate that a short-term administration of ketamine induced rapid antidepressant-like effects in adult male rats exposed to CUS conditions, effects that were not observed in response to the long-term treatment regime.
Shultz, Sandy R; MacFabe, Derrick F; Foley, Kelly A; Taylor, Roy; Cain, Donald P
2011-10-31
Brain concussion is a serious public health concern and is associated with short-term cognitive impairments and behavioral disturbances that typically occur in the absence of significant brain damage. The current study addresses the need to better understand the effects of a mild lateral fluid percussion injury on rat behavior and neuropathology in an animal model of concussion. Male Long-Evans rats received either a single mild fluid percussion injury or a sham-injury, and either a short (24h) or long (4 weeks) post-injury recovery period. After recovery, rats underwent a detailed behavioral analysis consisting of tests for rodent anxiety, cognition, social behavior, sensorimotor function, and depression-like behavior. After testing all rats were sacrificed and brains were examined immunohistochemically with markers for microglia/macrophage activation, reactive astrocytosis, and axonal injury. Injured rats (mean injury force: 1.20 ±.03 atm) displayed significant short-term cognitive impairments in the water maze and significantly more anxiolytic-like behavior in the elevated-plus maze compared to sham controls. Neuropathological analysis of the brains of injured rats showed an acute increase in reactive astrogliosis and activated microglia in cortex and evidence of axonal injury in the corpus callosum. There were no significant long-term effects on any behavioral or neuropathological measure 4 weeks after injury. These short-term behavioral and neuropathological changes are consistent with findings in human patients suffering a brain concussion, and provide further evidence for the use of a single mild lateral fluid percussion injury to study concussion in the rat. Copyright © 2011 Elsevier B.V. All rights reserved.
Zohar, Joseph; Matar, Michael A; Ifergane, Gal; Kaplan, Zeev; Cohen, Hagit
2008-09-01
The short- and long-term behavioral effects of a brief course of pregabalin, an antiepileptic structural analogue of alpha-aminobyturic acid with analgesic and anxiolytic effects, were assessed in an animal model of post-traumatic stress disorder (PTSD). Two-hundred thirty-three adult male Sprague-Dawley rats were employed. Behavioral responses to traumatic stress exposure (predator urine scent) were assessed immediately after (1 h) and 30 days after treatment with saline or pregabalin (at doses of 30, 100 and 300 mg/kg) in terms of behavior in the elevated plus maze (EPM) and the acoustic startle response (ASR) paradigms. At day 31 the freezing response to a trauma cue (clean cat litter) was assessed. The same treatment regimen initiated at day 7 was assessed at day 30 and in response to the trauma cue on day 31 in a separate experiment. In the short term, doses of 100 mg/kg and 300 mg/kg of pregabalin effectively attenuated anxiety-like behaviors. In the longer-term, pregabalin did not attenuate the onset of PTSD-like behaviors or the prevalence rates of severe cue-responses, for either the immediate or the delayed treatment regimens. Pregabalin may present an alternative compound for acute anxiolytic treatment after exposure to trauma, but has no long-term protective/preventive effects.
ERIC Educational Resources Information Center
Pole, Nnamdi; Ablon, J. Stuart; O'Connor, Lynn E.
2008-01-01
This article illustrates a method of testing models of change in individual long-term psychotherapy cases. A depressed client was treated with 208 sessions of control mastery therapy (CMT), an unmanualized approach that integrates elements of psychodynamic therapy (PDT) and cognitive behavioral therapy (CBT). Panels of experts developed prototypes…
Effects of physical aging on long-term creep of polymers and polymer matrix composites
NASA Technical Reports Server (NTRS)
Brinson, L. Catherine; Gates, Thomas S.
1994-01-01
For many polymeric materials in use below the glass transition temperature, the long term viscoelastic behavior is greatly affected by physical aging. To use polymer matrix composites as critical structural components in existing and novel technological applications, this long term behavior of the material system must be understood. Towards that end, this study applied the concepts governing the mechanics of physical aging in a consistent manner to the study of laminated composite systems. Even in fiber-dominated lay-ups the effects of physical aging are found to be important in the long-term behavior of the composite. The basic concepts describing physical aging of polymers are discussed. Several aspects of physical aging which have not been previously documented are also explored in this study, namely the effects of aging into equilibrium and a relationship to the time-temperature shift factor. The physical aging theory is then extended to develop the long-term compliance/modulus of a single lamina with varying fiber orientation. The latter is then built into classical lamination theory to predict long-time response of general oriented lamina and laminates. It is illustrated that the long term response can be counterintuitive, stressing the need for consistent modeling efforts to make long term predictions of laminates to be used in structural situations.
A Substance Called Food: Long-Term Psychodynamic Group Treatment for Compulsive Overeating.
Schwartz, Deborah C; Nickow, Marcia S; Arseneau, Ric; Gisslow, Mary T
2015-07-01
Obesity has proven difficult to treat. Many approaches neglect to address the deep-rooted underlying psychological issues. This paper describes a psychodynamically oriented approach to treating compulsive overeating as an addiction. Common to all addictions is a compulsion to consume a substance or engage in a behavior, a preoccupation with using behavior and rituals, and a lifestyle marked by an inability to manage the behavior and its harmful consequences. The approach represents a shift away from primarily medical models of intervention to integrated models focusing on the psychological underpinnings of obesity. Long-term psychodynamic group psychotherapy is recommended as a primary treatment.
ERIC Educational Resources Information Center
Golan, Hava; Huleihel, Mahmoud
2006-01-01
Hypoxia (H) and hypoxia-ischemia (HI) are major causes of foetal brain damage with long-lasting behavioral implications. The effect of hypoxia has been widely studied in human and a variety of animal models. In the present review, we summarize the latest studies testing the behavioral outcomes following prenatal hypoxia/hypoxia-ischemia in rodent…
Normann, Claus; Frase, Sibylle; Haug, Verena; von Wolff, Gregor; Clark, Kristin; Münzer, Patrick; Dorner, Alexandra; Scholliers, Jonas; Horn, Max; Vo Van, Tanja; Seifert, Gabriel; Serchov, Tsvetan; Biber, Knut; Nissen, Christoph; Klugbauer, Norbert; Bischofberger, Josef
2017-10-19
Long-term synaptic plasticity is a basic ability of the brain to dynamically adapt to external stimuli and regulate synaptic strength and ultimately network function. It is dysregulated by behavioral stress in animal models of depression and in humans with major depressive disorder. Antidepressants have been shown to restore disrupted synaptic plasticity in both animal models and humans; however, the underlying mechanism is unclear. We examined modulation of synaptic plasticity by selective serotonin reuptake inhibitors (SSRIs) in hippocampal brain slices from wild-type rats and serotonin transporter (SERT) knockout mice. Recombinant voltage-gated calcium (Ca 2+ ) channels in heterologous expression systems were used to determine the modulation of Ca 2+ channels by SSRIs. We tested the behavioral effects of SSRIs in the chronic behavioral despair model of depression both in the presence and in the absence of SERT. SSRIs selectively inhibited hippocampal long-term depression. The inhibition of long-term depression by SSRIs was mediated by a direct block of voltage-activated L-type Ca 2+ channels and was independent of SERT. Furthermore, SSRIs protected both wild-type and SERT knockout mice from behavioral despair induced by chronic stress. Finally, long-term depression was facilitated in animals subjected to the behavioral despair model, which was prevented by SSRI treatment. These results showed that antidepressants protected synaptic plasticity and neuronal circuitry from the effects of stress via a modulation of Ca 2+ channels and synaptic plasticity independent of SERT. Thus, L-type Ca 2+ channels might constitute an important signaling hub for stress response and for pathophysiology and treatment of depression. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Slovinec D'Angelo, Monika E; Pelletier, Luc G; Reid, Robert D; Huta, Veronika
2014-11-01
Poor adherence to regular exercise is a documented challenge among people with heart disease. Identifying key determinants of exercise adherence and distinguishing between the processes driving short- and long-term adherence to regular exercise is a valuable endeavor. The purpose of the present study was to test a model of exercise behavior change, which incorporates motivational orientations and self-efficacy for exercise behavior, in the prediction of short- and long-term exercise adherence. Male and female patients (N = 801) hospitalized for coronary heart disease were recruited from 3 tertiary care cardiac centers and followed for a period of 1 year after hospital discharge. A prospective, longitudinal design was used to examine the roles of motivation and self-efficacy (measured at recruitment and at 2 and 6 months after discharge) in the prediction of exercise behavior at 6 and 12 months. Baseline measures of exercise and clinical and demographic covariates were included in the analyses. Structural equation modeling showed that both autonomous motivation and self-efficacy were important determinants of short-term (6-month) exercise behavior regulation, but that only autonomous motivation remained a significant predictor of long-term (12-month) exercise behavior. Self-efficacy partially mediated the relationship between motivation for exercise and 6-month exercise behavior. This research confirmed the roles of autonomous motivation and self-efficacy in the health behavior change process and emphasized the key function of autonomous motivation in exercise maintenance. Theoretical and cardiac rehabilitation program applications of this research are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Combined Experimental and Computational Approach to Predict the Glass-Water Reaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, Eric M.; Bacon, Diana H.
2011-10-01
The use of mineral and glass dissolution rates measured in laboratory experiments to predict the weathering of primary minerals and volcanic and nuclear waste glasses in field studies requires the construction of rate models that accurately describe the weathering process over geologic timescales. Additionally, the need to model the long-term behavior of nuclear waste glass for the purpose of estimating radionuclide release rates requires that rate models be validated with long-term experiments. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test B, and pressurized unsaturated flow (PUF)], thereby reducingmore » the duration required to evaluate long-term performance. Currently, the PUF test is the only method that mimics the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitors the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior. A one-dimensional reactive chemical transport simulation of glass dissolution and secondary phase formation during a 1.5-year-long PUF experiment was conducted with the Subsurface Transport Over Reactive Multiphases (STORM) code. Results show that parameterization of the computer model by combining direct bench scale laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over the length of the experiment. Over the 1.5-year-long test duration, the rate decreased from 0.2 to 0.01 g/(m2 day) based on B release for low-activity waste glass LAWA44. The observed decrease is approximately two orders of magnitude higher than the decrease observed under static conditions with the SON68 glass (estimated to be a decrease by four orders of magnitude) and suggests that the gel-layer properties are less protective under these dynamic conditions.« less
Combined Experimental and Computational Approach to Predict the Glass-Water Reaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, Eric M; Bacon, Diana
2011-01-01
The use of mineral and glass dissolution rates measured in laboratory experiments to predict the weathering of primary minerals and volcanic and nuclear waste glasses in field studies requires the construction of rate models that accurately describe the weathering process over geologic time-scales. Additionally, the need to model the long-term behavior of nuclear waste glass for the purpose of estimating radionuclide release rates requires that rate models are validated with long-term experiments. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test-B, and pressurized unsaturated flow (PUF)], thereby reducing themore » duration required to evaluate long-term performance. Currently, the PUF test is the only method that mimics the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitors the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior. A one-dimensional reactive chemical transport simulation of glass dissolution and secondary phase formation during a 1.5-year long PUF experiment was conducted with the subsurface transport over reactive multi-phases code. Results show that parameterization of the computer model by combining direct bench-scale laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over the length of the experiment. Over the 1.5-year long test duration, the rate decreased from 0.2 to 0.01 g/(m2 d) base on B release. The observed decrease is approximately two orders of magnitude higher than the decrease observed under static conditions with the SON68 glass (estimated to be a decrease by 4 orders of magnitude) and suggest the gel-layer properties are less protective under these dynamic conditions.« less
NASA Astrophysics Data System (ADS)
Georgiou, Katerina; Abramoff, Rose; Harte, John; Riley, William; Torn, Margaret
2017-04-01
Climatic, atmospheric, and land-use changes all have the potential to alter soil microbial activity via abiotic effects on soil or mediated by changes in plant inputs. Recently, many promising microbial models of soil organic carbon (SOC) decomposition have been proposed to advance understanding and prediction of climate and carbon (C) feedbacks. Most of these models, however, exhibit unrealistic oscillatory behavior and SOC insensitivity to long-term changes in C inputs. Here we diagnose the sources of instability in four models that span the range of complexity of these recent microbial models, by sequentially adding complexity to a simple model to include microbial physiology, a mineral sorption isotherm, and enzyme dynamics. We propose a formulation that introduces density-dependence of microbial turnover, which acts to limit population sizes and reduce oscillations. We compare these models to results from 24 long-term C-input field manipulations, including the Detritus Input and Removal Treatment (DIRT) experiments, to show that there are clear metrics that can be used to distinguish and validate the inherent dynamics of each model structure. We find that widely used first-order models and microbial models without density-dependence cannot readily capture the range of long-term responses observed across the DIRT experiments as a direct consequence of their model structures. The proposed formulation improves predictions of long-term C-input changes, and implies greater SOC storage associated with CO2-fertilization-driven increases in C inputs over the coming century compared to common microbial models. Finally, we discuss our findings in the context of improving microbial model behavior for inclusion in Earth System Models.
Catic, Angela G; Mattison, Melissa L P; Bakaev, Innokentiy; Morgan, Marisa; Monti, Sara M; Lipsitz, Lewis
2014-12-01
To design, implement, and assess the pilot phase of an innovative, remote case-based video-consultation program called ECHO-AGE that links experts in the management of behavior disorders in patients with dementia to nursing home care providers. Pilot study involving surveying of participating long-term care sites regarding utility of recommendations and resident outcomes. Eleven long-term care sites in Massachusetts and Maine. An interprofessional specialty team at a tertiary care center and staff from 11 long-term care sites. Long-term care sites presented challenging cases regarding residents with dementia and/or delirium related behavioral issues to specialists via video-conferencing. Baseline resident characteristics and follow-up data regarding compliance with ECHO-AGE recommendations, resident improvement, hospitalization, and mortality were collected from the long-term care sites. Forty-seven residents, with a mean age of 82 years, were presented during the ECHO-AGE pilot period. Eighty-three percent of residents had a history of dementia and 44% were taking antipsychotic medications. The most common reasons for presentation were agitation, intrusiveness, and paranoia. Behavioral plans were recommended in 72.3% of patients. Suggestions for medication adjustments were also frequent. ECHO-AGE recommendations were completely or partially followed in 88.6% of residents. When recommendations were followed, sites were much more likely to report clinical improvement (74% vs 20%, P < .03). Hospitalization was also less common among residents for whom recommendations were followed. The results suggest that a case-based video-consultation program can be successful in improving the care of elders with dementia and/or delirium related behavioral issues by linking specialists with long-term care providers. Published by Elsevier Inc.
NASA Technical Reports Server (NTRS)
Gates, Thomas S.; Veazie, David R.; Brinson, L. Catherine
1996-01-01
Experimental and analytical methods were used to investigate the similarities and differences of the effects of physical aging on creep compliance of IM7/K3B composite loaded in tension and compression. Two matrix dominated loading modes, shear and transverse, were investigated for two load cases, tension and compression. The tests, run over a range of sub-glass transition temperatures, provided material constants, material master curves and aging related parameters. Comparing results from the short-term data indicated that although trends in the data with respect to aging time and aging temperature are similar, differences exist due to load direction and mode. The analytical model used for predicting long-term behavior using short-term data as input worked equally as well for the tension or compression loaded cases. Comparison of the loading modes indicated that the predictive model provided more accurate long term predictions for the shear mode as compared to the transverse mode. Parametric studies showed the usefulness of the predictive model as a tool for investigating long-term performance and compliance acceleration due to temperature.
Effect of environment on the long-term consequences of chronic pain
Bushnell, MC; Case, LK; Ceko, M; Cotton, VA; Gracely, JL; Low, LA; Pitcher, MH; Villemure, C
2014-01-01
Much evidence from pain patients and animal models shows that chronic pain does not exist in a vacuum, but has varied co-morbidities and far-reaching consequences. Patients with long-term pain often develop anxiety and depression and can manifest changes in cognitive functioning, particularly with working memory. Longitudinal studies in rodent models also show the development of anxiety-like behavior and cognitive changes weeks to months after an injury causing long-term pain. Brain imaging studies in pain patients and rodent models find that chronic pain is associated with anatomical and functional alterations in the brain. Nevertheless, studies in humans reveal that life-style choices, such as the practice of meditation or yoga, can reduce pain perception and have the opposite effect on the brain as does chronic pain. In rodent models, studies show that physical activity and a socially enriched environment reduce pain behavior and normalize brain function. Together, these studies suggest that the burden of chronic pain can be reduced by non-pharmacological interventions. PMID:25789436
3D Holographic Observatory for Long-term Monitoring of Complex Behaviors in Drosophila
NASA Astrophysics Data System (ADS)
Kumar, S. Santosh; Sun, Yaning; Zou, Sige; Hong, Jiarong
2016-09-01
Drosophila is an excellent model organism towards understanding the cognitive function, aging and neurodegeneration in humans. The effects of aging and other long-term dynamics on the behavior serve as important biomarkers in identifying such changes to the brain. In this regard, we are presenting a new imaging technique for lifetime monitoring of Drosophila in 3D at spatial and temporal resolutions capable of resolving the motion of limbs and wings using holographic principles. The developed system is capable of monitoring and extracting various behavioral parameters, such as ethograms and spatial distributions, from a group of flies simultaneously. This technique can image complicated leg and wing motions of flies at a resolution, which allows capturing specific landing responses from the same data set. Overall, this system provides a unique opportunity for high throughput screenings of behavioral changes in 3D over a long term in Drosophila.
Time Reparametrization Group and the Long Time Behavior in Quantum Glassy Systems
NASA Astrophysics Data System (ADS)
Kennett, Malcolm P.; Chamon, Claudio
2001-02-01
We study the long time dynamics of a quantum version of the Sherrington-Kirkpatrick model. Time reparametrizations of the dynamical equations have a parallel with renormalization group transformations; in this language the long time behavior of this model is controlled by a reparametrization group ( RpG) fixed point of the classical dynamics. The irrelevance of quantum terms in the dynamical equations in the aging regime explains the classical nature of the out of equilibrium fluctuation-dissipation relation.
Fuchs, Erich; Gruber, Christian; Reitmaier, Tobias; Sick, Bernhard
2009-09-01
Neural networks are often used to process temporal information, i.e., any kind of information related to time series. In many cases, time series contain short-term and long-term trends or behavior. This paper presents a new approach to capture temporal information with various reference periods simultaneously. A least squares approximation of the time series with orthogonal polynomials will be used to describe short-term trends contained in a signal (average, increase, curvature, etc.). Long-term behavior will be modeled with the tapped delay lines of a time-delay neural network (TDNN). This network takes the coefficients of the orthogonal expansion of the approximating polynomial as inputs such considering short-term and long-term information efficiently. The advantages of the method will be demonstrated by means of artificial data and two real-world application examples, the prediction of the user number in a computer network and online tool wear classification in turning.
DYT1 dystonia increases risk taking in humans.
Arkadir, David; Radulescu, Angela; Raymond, Deborah; Lubarr, Naomi; Bressman, Susan B; Mazzoni, Pietro; Niv, Yael
2016-06-01
It has been difficult to link synaptic modification to overt behavioral changes. Rodent models of DYT1 dystonia, a motor disorder caused by a single gene mutation, demonstrate increased long-term potentiation and decreased long-term depression in corticostriatal synapses. Computationally, such asymmetric learning predicts risk taking in probabilistic tasks. Here we demonstrate abnormal risk taking in DYT1 dystonia patients, which is correlated with disease severity, thereby supporting striatal plasticity in shaping choice behavior in humans.
A new model integrating short- and long-term aging of copper added to soils
Zeng, Saiqi; Li, Jumei; Wei, Dongpu
2017-01-01
Aging refers to the processes by which the bioavailability/toxicity, isotopic exchangeability, and extractability of metals added to soils decline overtime. We studied the characteristics of the aging process in copper (Cu) added to soils and the factors that affect this process. Then we developed a semi-mechanistic model to predict the lability of Cu during the aging process with descriptions of the diffusion process using complementary error function. In the previous studies, two semi-mechanistic models to separately predict short-term and long-term aging of Cu added to soils were developed with individual descriptions of the diffusion process. In the short-term model, the diffusion process was linearly related to the square root of incubation time (t1/2), and in the long-term model, the diffusion process was linearly related to the natural logarithm of incubation time (lnt). Both models could predict short-term or long-term aging processes separately, but could not predict the short- and long-term aging processes by one model. By analyzing and combining the two models, we found that the short- and long-term behaviors of the diffusion process could be described adequately using the complementary error function. The effect of temperature on the diffusion process was obtained in this model as well. The model can predict the aging process continuously based on four factors—soil pH, incubation time, soil organic matter content and temperature. PMID:28820888
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sham, Sam; Walker, Kevin P.
The expected service life of the Next Generation Nuclear Plant is 60 years. Structural analyses of the Intermediate Heat Exchanger (IHX) will require the development of unified viscoplastic constitutive models that address the material behavior of Alloy 617, a construction material of choice, over a wide range of strain rates. Many unified constitutive models employ a yield stress state variable which is used to account for cyclic hardening and softening of the material. For low stress values below the yield stress state variable these constitutive models predict that no inelastic deformation takes place which is contrary to experimental results. Themore » ability to model creep deformation at low stresses for the IHX application is very important as the IHX operational stresses are restricted to very small values due to the low creep strengths at elevated temperatures and long design lifetime. This paper presents some preliminary work in modeling the unified viscoplastic constitutive behavior of Alloy 617 which accounts for the long term, low stress, creep behavior and the hysteretic behavior of the material at elevated temperatures. The preliminary model is presented in one-dimensional form for ease of understanding, but the intent of the present work is to produce a three-dimensional model suitable for inclusion in the user subroutines UMAT and USERPL of the ABAQUS and ANSYS nonlinear finite element codes. Further experiments and constitutive modeling efforts are planned to model the material behavior of Alloy 617 in more detail.« less
The behavioral economics of violence.
Rachlin, Howard
2004-12-01
From the viewpoint of teleological behaviorism the first question to ask in attempting to understand any behavior, including violent behavior, is: What are its contingencies of reward and punishment? Or, to put the question in economic terms: What are the short-term and long-term costs and benefits that such behavior entails? Let us therefore consider the costs and benefits of youth violence. Among the short-term costs of violent behavior are the physical effort of the act, the possibility of immediate physical retaliation, immediate social disapproval, and the opportunity cost of other social acts that the violent behavior takes the place of (you can't be affectionate and violent at the same time, for instance). Among the immediate benefits of violent behavior are the intrinsic satisfaction of the violent act itself and any extrinsic benefit; if A violently appropriates B's new sneakers then obtaining the sneakers reinforces A's violence. These immediate benefits may well outweigh the costs in many contexts. Among the long-term costs of violent behavior are delayed retaliation, possible social disapproval and loss of social support, rejection from a social group, job loss, and health risks associated with a violent lifestyle. Among the long-term benefits are long-term intimidation of others (your neighbor is less likely to build a fence on your property if you have a reputation for violence), and a possibly exciting lifestyle. These long-term benefits may well be outweighed by the long-term costs. Opposition of long-term net costs to short-term net benefits, where it exists, creates a personal self-control trap: Overall satisfaction may decrease monotonically with rate of the target behavior but, regardless of its rate, the immediate satisfaction of doing it is always higher than that of not doing it. In the case of violent behavior, this trap is exacerbated by the fact that as a person's violence increases, net immediate reinforcement also increases (due to membership in violence-reinforcing subgroups). This contingency fits the "primrose path" addiction model of Prelec and Herrnstein. Violence is thus a paradigm case of behavioral addiction. I consider three ways of controlling such addictive behavior: by punishment, by extinction, and by substitution. The problem with punishment in the case of violence is that physical punishment tends to increase violent behavior while incarceration drives the punished person into the very social subgroup (the prison culture) where violence is maximally reinforced. The problem with extinction is that the immediate benefits of violent behavior are largely intrinsic and some costs (immediate retaliation by unidentified others) are difficult to control. The best way to control violent behavior, as well as other addictive behaviors, is by decreasing the price of economic substitutes. There is much evidence that addictions, such as to cocaine, heroin, alcohol, and tobacco, may be reduced by decreasing the price of social support. The same is predicted for violent behavior--either by providing social support directly or by training in social skills. In addition, in considering control of violent behavior, we need to examine the immediate benefits and long-term costs to society of having violent individuals and violence-reinforcing subcultures among us. And we need to act to reduce our own dependence on those benefits.
Evers, Ellen; de Vries, Han; Spruijt, Berry M.
2016-01-01
Whether and how primates are able to maintain long-term affiliative relationships is still under debate. Emotional bookkeeping (EB), the partner-specific accumulation of emotional responses to earlier interactions, is a candidate mechanism that does not require high cognitive abilities. EB is difficult to study in real animals, due to the complexity of primate social life. Therefore, we developed an agent-based model based on macaque behavior, the EMO-model, that implements arousal and two emotional dimensions, anxiety-FEAR and satisfaction-LIKE, which regulate social behavior. To implement EB, model individuals assign dynamic LIKE attitudes towards their group members, integrating partner-specific emotional responses to earlier received grooming episodes. Two key parameters in the model were varied to explore their effects on long-term affiliative relationships: (1) the timeframe over which earlier affiliation is accumulated into the LIKE attitudes; and (2) the degree of partner selectivity. EB over short and long timeframes gave rise to low variation in LIKE attitudes, and grooming partner preferences were only maintained over one to two months. Only EB over intermediate-term timeframes resulted in enough variation in LIKE attitudes, which, in combination with high partner selectivity, enables individuals to differentiate between regular and incidental grooming partners. These specific settings resulted in a strong feedback between differentiated LIKE attitudes and the distribution of grooming, giving rise to strongly reciprocated partner preferences that could be maintained for longer periods, occasionally up to one or two years. Moreover, at these settings the individual’s internal, socio-emotional memory of earlier affiliative episodes (LIKE attitudes) corresponded best to observable behavior (grooming partner preferences). In sum, our model suggests that intermediate-term LIKE dynamics and high partner selectivity seem most plausible for primates relying on emotional bookkeeping to maintain their social bonds. PMID:26839737
Evers, Ellen; de Vries, Han; Spruijt, Berry M; Sterck, Elisabeth H M
2016-01-01
Whether and how primates are able to maintain long-term affiliative relationships is still under debate. Emotional bookkeeping (EB), the partner-specific accumulation of emotional responses to earlier interactions, is a candidate mechanism that does not require high cognitive abilities. EB is difficult to study in real animals, due to the complexity of primate social life. Therefore, we developed an agent-based model based on macaque behavior, the EMO-model, that implements arousal and two emotional dimensions, anxiety-FEAR and satisfaction-LIKE, which regulate social behavior. To implement EB, model individuals assign dynamic LIKE attitudes towards their group members, integrating partner-specific emotional responses to earlier received grooming episodes. Two key parameters in the model were varied to explore their effects on long-term affiliative relationships: (1) the timeframe over which earlier affiliation is accumulated into the LIKE attitudes; and (2) the degree of partner selectivity. EB over short and long timeframes gave rise to low variation in LIKE attitudes, and grooming partner preferences were only maintained over one to two months. Only EB over intermediate-term timeframes resulted in enough variation in LIKE attitudes, which, in combination with high partner selectivity, enables individuals to differentiate between regular and incidental grooming partners. These specific settings resulted in a strong feedback between differentiated LIKE attitudes and the distribution of grooming, giving rise to strongly reciprocated partner preferences that could be maintained for longer periods, occasionally up to one or two years. Moreover, at these settings the individual's internal, socio-emotional memory of earlier affiliative episodes (LIKE attitudes) corresponded best to observable behavior (grooming partner preferences). In sum, our model suggests that intermediate-term LIKE dynamics and high partner selectivity seem most plausible for primates relying on emotional bookkeeping to maintain their social bonds.
Few long-term consequences after prolonged maternal separation in female Wistar rats
Abelson, Klas S. P.; Nylander, Ingrid; Roman, Erika
2017-01-01
Environmental factors during the early-life period are known to have long-term consequences for the adult phenotype. An intimate interplay between genes and environment shape the individual and may affect vulnerability for psychopathology in a sex-dependent manner. A rodent maternal separation model was here used to study the long-term effects of different early-life rearing conditions on adult behavior, HPA axis activity and long-term voluntary alcohol intake in female rats. Litters were subjected to 15 min (MS15) or 360 min (MS360) of daily maternal separation during postnatal day 1–21. In adulthood, the behavioral profiles were investigated using the multivariate concentric square field™ (MCSF) test or examined for HPA axis reactivity by cat-odor exposure with subsequent characterization of voluntary alcohol intake and associated changes in HPA axis activity. Adult female MS360 offspring showed mostly no, or only minor, effects on behavior, HPA axis reactivity and long-term alcohol intake relative to MS15. Instead, more pronounced effects were found dependent on changes in the natural hormonal cycle or by the choice of animal supplier. However, changes were revealed in corticosterone load after long-term alcohol access, as females subjected to MS360 had higher concentrations of fecal corticosterone. The present findings are in line with and expand on previous studies on the long-term effects of maternal separation in female rats with regard to behavior, HPA axis activity and voluntary alcohol intake. It can also be a window into further studies detailing how early-life experiences interact with other risk and protective factors to impact the adult phenotype and how possible sex differences play a role. PMID:29267376
Leffa, Douglas Teixeira; Bellaver, Bruna; Salvi, Artur Alban; de Oliveira, Carla; Caumo, Wolnei; Grevet, Eugenio Horacio; Fregni, Felipe; Quincozes-Santos, André; Rohde, Luis Augusto; Torres, Iraci L S
2018-04-05
Transcranial direct current stimulation (tDCS) is a technique that modulates neuronal activity and has been proposed as a potential therapeutic tool for attention-deficit/hyperactivity disorder (ADHD) symptoms. Although pilot studies have shown evidence of efficacy, its mechanism of action remains unclear. We evaluated the effects of tDCS on behavioral (working and long-term memory) and neurochemical (oxidative and inflammatory parameters) outcomes related to ADHD pathophysiology. We used the most widely accepted animal model of ADHD: spontaneously hypertensive rats (SHR). The selected behavioral outcomes have been shown to be altered in both ADHD patients and animal models, and were chosen for their relation to the proposed mechanistic action of tDCS. Adult male SHR and their control, the Wistar Kyoto rats (WKY), were subjected to 20 min of bicephalic tDCS or sham stimulation for 8 consecutive days. Working memory, long-term memory, and neurochemical outcomes were evaluated. TDCS improved long-term memory deficits presented by the SHR. No change in working memory performance was observed. In the hippocampus, tDCS increased both the production of reactive oxygen species in SHR and the levels of the antioxidant molecule glutathione in both strains. TDCS also modulated inflammatory response in the brains of WKY by downregulating pro-inflammatory cytokines. TDCS had significant effects that were specific for strain, type of behavioral and neurochemical outcomes. The long-term memory improvement in the SHR may point to a possible therapeutic role of tDCS in ADHD that does not seem to be mediated by inflammatory markers. Additionally, the anti-inflammatory effects observed in the brain of WKY after tDCS needs to be further explored. Copyright © 2018 Elsevier Inc. All rights reserved.
Nomadic-colonial life strategies enable paradoxical survival and growth despite habitat destruction
Tan, Zong Xuan; Cheong, Kang Hao
2017-01-01
Organisms often exhibit behavioral or phenotypic diversity to improve population fitness in the face of environmental variability. When each behavior or phenotype is individually maladaptive, alternating between these losing strategies can counter-intuitively result in population persistence–an outcome similar to the Parrondo’s paradox. Instead of the capital or history dependence that characterize traditional Parrondo games, most ecological models which exhibit such paradoxical behavior depend on the presence of exogenous environmental variation. Here we present a population model that exhibits Parrondo’s paradox through capital and history-dependent dynamics. Two sub-populations comprise our model: nomads, who live independently without competition or cooperation, and colonists, who engage in competition, cooperation, and long-term habitat destruction. Nomads and colonists may alternate behaviors in response to changes in the colonial habitat. Even when nomadism and colonialism individually lead to extinction, switching between these strategies at the appropriate moments can paradoxically enable both population persistence and long-term growth. DOI: http://dx.doi.org/10.7554/eLife.21673.001 PMID:28084993
Holmes, Megan R
2013-09-01
Children who have been exposed to intimate partner violence (IPV) experience a wide variety of short-term social adjustment and emotional difficulties, including externalizing behavioral problems such as aggression. While children are affected by IPV at all ages, little is known about the long-term consequences of IPV exposure at younger ages. Because early experiences provide the foundation for later development, children exposed to IPV as an infant or toddler may experience worse negative outcomes over time than children never exposed. Using the National Survey of Child and Adolescent Well-Being (NSCAW), latent growth curve modeling was conducted to examine whether early IPV exposure occurring between birth and age three (n = 107), compared with no exposure (n = 339), affects the development of aggressive behavior over 5 years. This modeling allowed for empirical exploration of developmental trajectories, and considered whether initial social development trajectories and change over time vary according to early IPV exposure. Children who were exposed to more frequent early IPV did not have significantly different aggressive behavior problems initially than children who were never exposed. However, over time, the more frequently children were exposed between birth and 3 years, the more aggressive behavior problems were exhibited by age eight. Results indicate a long-term negative behavioral effect on children who have been exposed to IPV at an early age. An initial assessment directly following exposure to IPV may not be able to identify behavior problems in young children. Because the negative effects of early IPV exposure are delayed until the child is of school age, early intervention is necessary for reducing the risk of later aggressive behavior. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.
Consequences of stage-structured predators: cannibalism, behavioral effects, and trophic cascades.
Rudolf, Volker H W
2007-12-01
Cannibalistic and asymmetrical behavioral interactions between stages are common within stage-structured predator populations. Such direct interactions between predator stages can result in density- and trait-mediated indirect interactions between a predator and its prey. A set of structured predator-prey models is used to explore how such indirect interactions affect the dynamics and structure of communities. Analyses of the separate and combined effects of stage-structured cannibalism and behavior-mediated avoidance of cannibals under different ecological scenarios show that both cannibalism and behavioral avoidance of cannibalism can result in short- and long-term positive indirect connections between predator stages and the prey, including "apparent mutualism." These positive interactions alter the strength of trophic cascades such that the system's dynamics are determined by the interaction between bottom-up and top-down effects. Contrary to the expectation of simpler models, enrichment increases both predator and prey abundance in systems with cannibalism or behavioral avoidance of cannibalism. The effect of behavioral avoidance of cannibalism, however, depends on how strongly it affects the maturation rate of the predator. Behavioral interactions between predator stages reduce the short-term positive effect of cannibalism on the prey density, but can enhance its positive long-term effects. Both interaction types reduce the destabilizing effect of enrichment. These results suggest that inconsistencies between data and simple models can be resolved by accounting for stage-structured interactions within and among species.
Use of a Behavioral Contract with Resident Assistants: Prelude to a Health Fair.
ERIC Educational Resources Information Center
Morgan, John D.; Hyner, Gerald C.
1984-01-01
Presents a conceptual model which focuses on goals of student government in residence halls. The model has two fundamental processes. One focuses on short term goals and activities catering to creation of environment. The second has long term effects referred to as lifelong personal development. (JAC)
DYT1 dystonia increases risk taking in humans
Arkadir, David; Radulescu, Angela; Raymond, Deborah; Lubarr, Naomi; Bressman, Susan B; Mazzoni, Pietro; Niv, Yael
2016-01-01
It has been difficult to link synaptic modification to overt behavioral changes. Rodent models of DYT1 dystonia, a motor disorder caused by a single gene mutation, demonstrate increased long-term potentiation and decreased long-term depression in corticostriatal synapses. Computationally, such asymmetric learning predicts risk taking in probabilistic tasks. Here we demonstrate abnormal risk taking in DYT1 dystonia patients, which is correlated with disease severity, thereby supporting striatal plasticity in shaping choice behavior in humans. DOI: http://dx.doi.org/10.7554/eLife.14155.001 PMID:27249418
Self-Monitoring Success and Failure: Evidence for a Mediating Mechanism.
ERIC Educational Resources Information Center
Susser, Howard S.
Two theories, the closed loop model (divides self-regulation into self-monitoring, self-evaluation, and self-reinforcement) and the non-mediational model (defines self-regulation as behavior that is controlled by its long-term and observable consequences), have been proposed to explain why behavior changes when self-monitoring occurs. Both…
Blaze, Jennifer; Roth, Tania L.
2015-01-01
While it is well-known that stress during development and adulthood can confer long-term neurobiological and behavioral consequences, investigators have only recently begun to assess epigenetic modifications associated with these consequences. In this review, we highlight clinical research and work with animal models that provide evidence of the impact of stressful experiences either during the perinatal period or adulthood on DNA methylation and behavior. Additionally, we explore the more controversial concept of transgenerational inheritance, including that associated with preconception stress experienced by the mother or father. Finally, we discuss challenges associated with the idea of transgenerational epigenetics and for the field of epigenetics in general. PMID:25917771
Reaction modeling of drainage quality in the Duluth Complex, northern Minnesota, USA
Seal, Robert; Lapakko, Kim; Piatak, Nadine; Woodruff, Laurel G.
2015-01-01
Reaction modeling can be a valuable tool in predicting the long-term behavior of waste material if representative rate constants can be derived from long-term leaching tests or other approaches. Reaction modeling using the REACT program of the Geochemist’s Workbench was conducted to evaluate long-term drainage quality affected by disseminated Cu-Ni-(Co-)-PGM sulfide mineralization in the basal zone of the Duluth Complex where significant resources have been identified. Disseminated sulfide minerals, mostly pyrrhotite and Cu-Fe sulfides, are hosted by clinopyroxene-bearing troctolites. Carbonate minerals are scarce to non-existent. Long-term simulations of up to 20 years of weathering of tailings used two different sets of rate constants: one based on published laboratory single-mineral dissolution experiments, and one based on leaching experiments using bulk material from the Duluth Complex conducted by the Minnesota Department of Natural Resources (MNDNR). The simulations included only plagioclase, olivine, clinopyroxene, pyrrhotite, and water as starting phases. Dissolved oxygen concentrations were assumed to be in equilibrium with atmospheric oxygen. The simulations based on the published single-mineral rate constants predicted that pyrrhotite would be effectively exhausted in less than two years and pH would rise accordingly. In contrast, only 20 percent of the pyrrhotite was depleted after two years using the MNDNR rate constants. Predicted pyrrhotite depletion by the simulation based on the MNDNR rate constant matched well with published results of laboratory tests on tailings. Modeling long-term weathering of mine wastes also can provide important insights into secondary reactions that may influence the permeability of tailings and thereby affect weathering behavior. Both models predicted the precipitation of a variety of secondary phases including goethite, gibbsite, and clay (nontronite).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, Eric M.; Bacon, Diana H.
2009-09-21
The interest in the long-term durability of waste glass stems from the need to predict radionuclide release rates from the corroding glass over geologic time-scales. Several long-term test methods have been developed to accelerate the glass-water reaction [drip test, vapor hydration test, product consistency test-B, and pressurized unsaturated flow (PUF)]. Currently, the PUF test is the only method that can mimic the unsaturated hydraulic properties expected in a subsurface disposal facility and simultaneously monitor the glass-water reaction. PUF tests are being conducted to accelerate the weathering of glass and validate the model parameters being used to predict long-term glass behavior.more » One dimensional reactive chemical transport simulations of glass dissolution and secondary phase formation during a 1.5-year long PUF experiment was conducted with the subsurface transport over reactive multi-phases (STORM) code. Results show that parameterization of the computer model by combining direct laboratory measurements and thermodynamic data provides an integrated approach to predicting glass behavior over geologic-time scales.« less
Combined Economic and Hydrologic Modeling to Support Collaborative Decision Making Processes
NASA Astrophysics Data System (ADS)
Sheer, D. P.
2008-12-01
For more than a decade, the core concept of the author's efforts in support of collaborative decision making has been a combination of hydrologic simulation and multi-objective optimization. The modeling has generally been used to support collaborative decision making processes. The OASIS model developed by HydroLogics Inc. solves a multi-objective optimization at each time step using a mixed integer linear program (MILP). The MILP can be configured to include any user defined objective, including but not limited too economic objectives. For example, an estimated marginal value for water for crops and M&I use were included in the objective function to drive trades in a model of the lower Rio Grande. The formulation of the MILP, constraints and objectives, in any time step is conditional: it changes based on the value of state variables and dynamic external forcing functions, such as rainfall, hydrology, market prices, arrival of migratory fish, water temperature, etc. It therefore acts as a dynamic short term multi-objective economic optimization for each time step. MILP is capable of solving a general problem that includes a very realistic representation of the physical system characteristics in addition to the normal multi-objective optimization objectives and constraints included in economic models. In all of these models, the short term objective function is a surrogate for achieving long term multi-objective results. The long term performance for any alternative (especially including operating strategies) is evaluated by simulation. An operating rule is the combination of conditions, parameters, constraints and objectives used to determine the formulation of the short term optimization in each time step. Heuristic wrappers for the simulation program have been developed improve the parameters of an operating rule, and are initiating research on a wrapper that will allow us to employ a genetic algorithm to improve the form of the rule (conditions, constraints, and short term objectives) as well. In the models operating rules represent different models of human behavior, and the objective of the modeling is to find rules for human behavior that perform well in terms of long term human objectives. The conceptual model used to represent human behavior incorporates economic multi-objective optimization for surrogate objectives, and rules that set those objectives based on current conditions and accounting for uncertainty, at least implicitly. The author asserts that real world operating rules follow this form and have evolved because they have been perceived as successful in the past. Thus, the modeling efforts focus on human behavior in much the same way that economic models focus on human behavior. This paper illustrates the above concepts with real world examples.
Adamo, Federica; Farina, Marco; Thekkedath, Usha R; Grattoni, Alessandro; Sesana, Raffaella
2018-06-01
Cell transplantation in bioengineered scaffolds and encapsulation systems has shown great promise in regenerative medicine. Depending on the site of implantation, type of cells and their expected function, these systems are designed to provide cells with a physiological-like environment while providing mechanical support and promoting long-term viability and function of the graft. A minimally invasive 3D printed system termed neovascularized implantable cell homing and encapsulation (NICHE) was developed in polylactic acid for subcutaneous transplantation of endocrine cells, including pancreatic islets. The suitability of the NICHE for long term in vivo deployment is investigated by assessing mechanical behavior of both fresh devices under simulated subcutaneous conditions and NICHE retrieved from subcutaneous implantation in pigs. Both experimental and numerical studies were performed with a focus on validating the constitutive material model used in the numerical analysis for accuracy and reliability. Notably, homogeneous isotropic constitutive material model calibrated by means of uniaxial testing well suited experimental results. The results highlight the long term durability for in vivo applications and the potential applicability of the model to predict the mechanical behavior of similar devices in various physiological settings. Copyright © 2018 Elsevier Ltd. All rights reserved.
Long-term functional recovery and compensation after cerebral ischemia in rats.
Girard, Sylvie; Murray, Katie N; Rothwell, Nancy J; Metz, Gerlinde A S; Allan, Stuart M
2014-08-15
Cerebral ischemia is one of the most common causes of disabilities in adults and leads to long-term motor and cognitive impairments with limited therapeutic possibilities. Treatment options have proven efficient in preclinical models of cerebral ischemia but have failed in the clinical setting. This limited translation may be due to the suitability of models used and outcomes measured as most studies have focused on the early period after injury with gross motor scales, which have limited correlation to the clinical situation. The aim of this study was to determine long-term functional outcomes after cerebral ischemia in rats, focusing on fine motor function, social and depressive behavior as clinically relevant measures. A secondary objective was to evaluate the effects of an anti-inflammatory treatment (interleukin-1 receptor antagonist (IL-1Ra)) on functional recovery and compensation. Infarct volume was correlated with long-term (25 days) impairments in fine motor skills, but not with emotional components of behavior. Motor impairments could not be detected using conventional neurological tests and only detailed analysis allowed differentiation between recovery and compensation. Acute systemic administration of IL-1Ra (at reperfusion) led to a faster and more complete recovery, but delayed (24h) IL-1Ra treatment had no effect. In summary functional assessment after brain injury requires detailed motor tests in order to address long-term impairments and compensation processes that are mediated by intact tissues. Functional deficits in skilled movement after brain injury represent ideal predictors of long-term outcomes and should become standard measures in the assessment of preclinical animal models. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.
van Hartevelt, Tim J; Cabral, Joana; Møller, Arne; FitzGerald, James J; Green, Alexander L; Aziz, Tipu Z; Deco, Gustavo; Kringelbach, Morten L
2015-01-01
It is unclear whether Hebbian-like learning occurs at the level of long-range white matter connections in humans, i.e., where measurable changes in structural connectivity (SC) are correlated with changes in functional connectivity. However, the behavioral changes observed after deep brain stimulation (DBS) suggest the existence of such Hebbian-like mechanisms occurring at the structural level with functional consequences. In this rare case study, we obtained the full network of white matter connections of one patient with Parkinson's disease (PD) before and after long-term DBS and combined it with a computational model of ongoing activity to investigate the effects of DBS-induced long-term structural changes. The results show that the long-term effects of DBS on resting-state functional connectivity is best obtained in the computational model by changing the structural weights from the subthalamic nucleus (STN) to the putamen and the thalamus in a Hebbian-like manner. Moreover, long-term DBS also significantly changed the SC towards normality in terms of model-based measures of segregation and integration of information processing, two key concepts of brain organization. This novel approach using computational models to model the effects of Hebbian-like changes in SC allowed us to causally identify the possible underlying neural mechanisms of long-term DBS using rare case study data. In time, this could help predict the efficacy of individual DBS targeting and identify novel DBS targets.
Murphy, Michelle; Mills, Sierra; Winstone, Joanna; Leishman, Emma; Wager-Miller, Jim; Bradshaw, Heather; Mackie, Ken
2017-01-01
Introduction: The high prevalence of adolescent cannabis use, the association between this use and later psychiatric disease, and increased access to high-potency cannabis highlight the need for a better understanding of the long-term effects of adolescent cannabis use on cognitive and behavioral outcomes. Furthermore, increasing Δ 9 -tetrahydrocannabinol (THC) in high-potency cannabis is accompanied by a decrease in cannabidiol (CBD), thus an understanding of the interactions between CBD and THC in the neurodevelopmental effects of THC is also important. The current study examined the immediate and long-term behavioral consequences of THC, CBD, and their combination in a mouse model of adolescent cannabis use. Materials and Methods: Male CD1 mice received daily injections of THC (3 mg/kg), CBD (3 mg/kg), CBD+THC (3 mg/kg each), vehicle, or remained undisturbed in their home cage (no handling/injections), either during adolescence (postnatal day [PND] 28-48) or during early adulthood (PND 69-89). Animals were then evaluated with a battery of behavioral tests 1 day after drug treatment, and again after 42 drug-free days. The tests included the following: open field (day 1), novel object recognition (NOR; day 2), marble burying (day 3), elevated plus maze (EPM; day 4), and Nestlet shredding (day 5). Results: Chronic administration of THC during adolescence led to immediate and long-term impairments in object recognition/working memory, as measured by the NOR task. In contrast, adult administration of THC caused immediate, but not long term, impairment of object/working memory. Adolescent chronic exposure to THC increased repetitive and compulsive-like behaviors, as measured by the Nestlet shredding task. Chronic administration of THC, either during adolescence or during adulthood, led to a delayed increase in anxiety as measured by the EPM. All THC-induced behavioral abnormalities were prevented by the coadministration of CBD+THC, whereas CBD alone did not influence behavioral outcomes. Conclusion: These data suggest that chronic exposure to THC during adolescence leads to some of the behavioral abnormalities common in schizophrenia. Interestingly, CBD appeared to antagonize all THC-induced behavioral abnormalities. These findings support the hypothesis that adolescent THC use can impart long-term behavioral deficits; however, cotreatment with CBD prevents these deficits.
Murphy, Michelle; Mills, Sierra; Winstone, Joanna; Leishman, Emma; Wager-Miller, Jim; Bradshaw, Heather; Mackie, Ken
2017-01-01
Abstract Introduction: The high prevalence of adolescent cannabis use, the association between this use and later psychiatric disease, and increased access to high-potency cannabis highlight the need for a better understanding of the long-term effects of adolescent cannabis use on cognitive and behavioral outcomes. Furthermore, increasing Δ9-tetrahydrocannabinol (THC) in high-potency cannabis is accompanied by a decrease in cannabidiol (CBD), thus an understanding of the interactions between CBD and THC in the neurodevelopmental effects of THC is also important. The current study examined the immediate and long-term behavioral consequences of THC, CBD, and their combination in a mouse model of adolescent cannabis use. Materials and Methods: Male CD1 mice received daily injections of THC (3 mg/kg), CBD (3 mg/kg), CBD+THC (3 mg/kg each), vehicle, or remained undisturbed in their home cage (no handling/injections), either during adolescence (postnatal day [PND] 28–48) or during early adulthood (PND 69–89). Animals were then evaluated with a battery of behavioral tests 1 day after drug treatment, and again after 42 drug-free days. The tests included the following: open field (day 1), novel object recognition (NOR; day 2), marble burying (day 3), elevated plus maze (EPM; day 4), and Nestlet shredding (day 5). Results: Chronic administration of THC during adolescence led to immediate and long-term impairments in object recognition/working memory, as measured by the NOR task. In contrast, adult administration of THC caused immediate, but not long term, impairment of object/working memory. Adolescent chronic exposure to THC increased repetitive and compulsive-like behaviors, as measured by the Nestlet shredding task. Chronic administration of THC, either during adolescence or during adulthood, led to a delayed increase in anxiety as measured by the EPM. All THC-induced behavioral abnormalities were prevented by the coadministration of CBD+THC, whereas CBD alone did not influence behavioral outcomes. Conclusion: These data suggest that chronic exposure to THC during adolescence leads to some of the behavioral abnormalities common in schizophrenia. Interestingly, CBD appeared to antagonize all THC-induced behavioral abnormalities. These findings support the hypothesis that adolescent THC use can impart long-term behavioral deficits; however, cotreatment with CBD prevents these deficits. PMID:29098186
The Price of Fame: The Impact of Stimulus Familiarity on Proactive Interference Resolution
Prabhakaran, Ranjani; Thompson-Schill, Sharon L.
2013-01-01
Interference from previously learned information, known as proactive interference (PI), limits our memory retrieval abilities. Previous studies of PI resolution have focused on the role of short-term familiarity, or recency, in causing PI. In the present study, we investigated the impact of long-term stimulus familiarity on PI resolution processes. In two behavioral experiments and one event-related fMRI experiment, long-term familiarity was manipulated through the use of famous and nonfamous stimuli, and short-term familiarity was manipulated through the use of recent and nonrecent probe items in an item recognition task. The right middle frontal gyrus demonstrated greater sensitivity to famous stimuli, suggesting that long-term stimulus familiarity plays a role in influencing PI resolution processes. Further examination of the effect of long-term stimulus familiarity on PI resolution revealed a larger behavioral interference effect for famous stimuli, but only under speeded response conditions. Thus, models of memory retrieval—and of the cognitive control mechanisms that guide retrieval processes—should consider the impact of and interactions among sources of familiarity on multiple time scales. PMID:20429858
The price of fame: the impact of stimulus familiarity on proactive interference resolution.
Prabhakaran, Ranjani; Thompson-Schill, Sharon L
2011-04-01
Interference from previously learned information, known as proactive interference (PI), limits our memory retrieval abilities. Previous studies of PI resolution have focused on the role of short-term familiarity, or recency, in causing PI. In the present study, we investigated the impact of long-term stimulus familiarity on PI resolution processes. In two behavioral experiments and one event-related fMRI experiment, long-term familiarity was manipulated through the use of famous and nonfamous stimuli, and short-term familiarity was manipulated through the use of recent and nonrecent probe items in an item recognition task. The right middle frontal gyrus demonstrated greater sensitivity to famous stimuli, suggesting that long-term stimulus familiarity plays a role in influencing PI resolution processes. Further examination of the effect of long-term stimulus familiarity on PI resolution revealed a larger behavioral interference effect for famous stimuli, but only under speeded response conditions. Thus, models of memory retrieval--and of the cognitive control mechanisms that guide retrieval processes--should consider the impact of and interactions among sources of familiarity on multiple time scales.
Allen, Victoria W; Shirasu-Hiza, Mimi
2018-01-01
Despite being pervasive, the control of programmed grooming is poorly understood. We addressed this gap by developing a high-throughput platform that allows long-term detection of grooming in Drosophila melanogaster. In our method, a k-nearest neighbors algorithm automatically classifies fly behavior and finds grooming events with over 90% accuracy in diverse genotypes. Our data show that flies spend ~13% of their waking time grooming, driven largely by two major internal programs. One of these programs regulates the timing of grooming and involves the core circadian clock components cycle, clock, and period. The second program regulates the duration of grooming and, while dependent on cycle and clock, appears to be independent of period. This emerging dual control model in which one program controls timing and another controls duration, resembles the two-process regulatory model of sleep. Together, our quantitative approach presents the opportunity for further dissection of mechanisms controlling long-term grooming in Drosophila. PMID:29485401
Zhang, Lisheng; Zhang, Lingling; Shi, Dongtao; Wei, Jing; Chang, Yaqing
2017-01-01
Increases in ocean temperature due to climate change are predicted to change the behaviors of marine invertebrates. Altered behaviors of keystone ecosystem engineers such as echinoderms will have consequences for the fitness of individuals, which are expected to flow on to the local ecosystem. Relatively few studies have investigated the behavioral responses of echinoderms to long-term elevated temperature. We investigated the effects of exposure to long-term (∼31 weeks) elevated temperature (∼3 °C above the ambient water temperature) on covering, sheltering and righting behaviors of the sea urchin Strongylocentrotus intermedius. Long-term elevated temperature showed different effects on the three behaviors. It significantly decreased covering behavior, including both covering behavior reaction (time to first covering) and ability (number of covered sea urchins and number of shells used for covering). Conversely, exposure to long-term elevated temperature significantly increased sheltering behavior. Righting response in S. intermedius was not significantly different between temperature treatments. The results provide new information into behavioral responses of echinoderms to ocean warming. PMID:28348933
Effects of Aging-Time Reference on the Long Term Behavior of the IM7/K3B Composite
NASA Technical Reports Server (NTRS)
Veazie, David R.; Gates, Thomas S.
1998-01-01
An analytical study was undertaken to investigate the effects of the time-based shift reference on the long term behavior of the graphite reinforced thermoplastic polyimide composite IM7/K3B at elevated temperature. Creep compliance and the effects of physical aging on the time dependent response was measured for uniaxial loading at several isothermal conditions below the glass transition temperature (T(sub g). Two matrix dominated loading modes, shear and transverse, were investigated in tension and compression. The momentary sequenced creep/aging curves were collapsed through a horizontal (time) shift using the shortest, middle and longest aging time curve as the reference curve. Linear viscoelasticity was used to characterize the creep/recovery behavior and superposition techniques were used to establish the physical aging related material constants. The use of effective time expressions in a laminated plate model allowed for the prediction of long term creep compliance. The effect of using different reference curves with time/aging-time superposition was most sensitive to the physical aging shift rate at lower test temperatures. Depending on the loading mode, the reference curve used can result in a more accurate long term prediction, especially at lower test temperatures.
A multiscale climate emulator for long-term morphodynamics (MUSCLE-morpho)
NASA Astrophysics Data System (ADS)
Antolínez, José Antonio A.; Méndez, Fernando J.; Camus, Paula; Vitousek, Sean; González, E. Mauricio; Ruggiero, Peter; Barnard, Patrick
2016-01-01
Interest in understanding long-term coastal morphodynamics has recently increased as climate change impacts become perceptible and accelerated. Multiscale, behavior-oriented and process-based models, or hybrids of the two, are typically applied with deterministic approaches which require considerable computational effort. In order to reduce the computational cost of modeling large spatial and temporal scales, input reduction and morphological acceleration techniques have been developed. Here we introduce a general framework for reducing dimensionality of wave-driver inputs to morphodynamic models. The proposed framework seeks to account for dependencies with global atmospheric circulation fields and deals simultaneously with seasonality, interannual variability, long-term trends, and autocorrelation of wave height, wave period, and wave direction. The model is also able to reproduce future wave climate time series accounting for possible changes in the global climate system. An application of long-term shoreline evolution is presented by comparing the performance of the real and the simulated wave climate using a one-line model. This article was corrected on 2 FEB 2016. See the end of the full text for details.
NASA Technical Reports Server (NTRS)
Ruley, John D.
1986-01-01
In the design of spacecraft for proper thermal balance, accurate information on the long-term optical behavior of the spacecraft outer skin materials is necessary. A phenomenological model for such behavior is given. The underlying principles are explained and some examples are given of the model's fit to actual measurements under simulated Earth-orbit conditions. Comments are given on the applicability of the model to materials testing and thermal modelling.
Haase, Claudia M.; Holley, Sarah; Bloch, Lian; Verstaen, Alice; Levenson, Robert W.
2016-01-01
Objectively coded interpersonal emotional behaviors that emerged during a 15-minute marital conflict interaction predicted the development of physical symptoms in a 20-year longitudinal study of long-term marriages. Dyadic latent growth curve modeling showed that anger behavior predicted increases in cardiovascular symptoms and stonewalling behavior predicted increases in musculoskeletal symptoms. Both associations were found for husbands (although cross-lagged path models also showed some support for wives) and were controlled for sociodemographic characteristics (age, education) and behaviors (i.e., exercise, smoking, alcohol consumption, caffeine consumption) known to influence health. Both associations did not exist at the start of the study, but only emerged over the ensuing 20 years. There was some support for the specificity of these relationships (i.e., stonewalling behavior did not predict cardiovascular symptoms; anger behavior did not predict musculoskeletal symptoms; neither symptom was predicted by fear nor sadness behavior), with the anger-cardiovascular relationship emerging as most robust. Using cross-lagged path models to probe directionality of these associations, emotional behaviors predicted physical health symptoms over time (with some reverse associations found as well). These findings illuminate longstanding theoretical and applied issues concerning the association between interpersonal emotional behaviors and physical health and suggest opportunities for preventive interventions focused on specific emotions to help address major public health problems. PMID:27213730
Gibbs, Bethany Barone; Kinzel, Laura S.; Gabriel, Kelley Pettee; Chang, Yue-fang; Kuller, Lewis H.
2012-01-01
Background Standard behavioral obesity treatment produces poor long-term results. Focusing on healthy eating behaviors, rather than caloric intake, may be an alternative strategy. Furthermore, important behaviors might differ for short- vs. long-term weight control. Objective To describe and compare associations between changes in eating behaviors and weight after 6 and 48 months Design Secondary analysis of data collected during a randomized weight loss intervention trial with 48-month follow-up Participants 465 overweight and obese postmenopausal women enrolled in the Women on the Move through Activity and Nutrition (WOMAN) Study Main outcome measures Changes in weight from baseline to 6 and 48 months. Statistical analyses performed Linear regression models examined the associations between 6- and 48-month changes in eating habits assessed by the Conner Diet Habit Survey and changes in weight. Analyses were conducted in the combined study population and stratified by randomization group. Results At 6 months in the combined population, weight loss was independently associated with decreased desserts (p<0.001), restaurant eating (p=0.042), sugar-sweetened beverages (p=0.009), and fried foods (p<0.001), and increased fish consumption (p=0.003). Results were similar in intervention participants; only reduced desserts and fried foods associated with weight loss in controls. At 48 months in the combined population, weight loss was again associated with decreased desserts (p=0.003) and sugar-sweetened beverages (p=0.011), but also decreased meats/cheeses (p=0.024) and increased fruits/vegetables (p<0.001). Decreased meats/cheeses predicted weight loss in intervention participants; desserts, sugar-sweetened beverages, and fruits/vegetables were independently associated in controls. Conclusions Changes in eating behaviors were associated with weight change, though important behaviors differed for short- and long-term weight change and by randomization group. Future studies should determine whether interventions targeting these behaviors could improve long-term obesity treatment outcomes. PMID:22939439
Environmental effects on long term behavior of composite laminates
NASA Astrophysics Data System (ADS)
Singhal, S. N.; Chamis, C. C.
Model equations are presented for approximate methods simulating the long-term behavior of composite materials and structures in hot/humid service environments. These equations allow laminate property upgradings with time, and can account for the effects of service environments on creep response. These methodologies are illustrated for various individual and coupled temperature/moisture, longitudinal/transverse, and composite material type cases. Creep deformation is noted to rise dramatically for cases of matrix-borne, but not of fiber-borne, loading in hot, humid environments; the coupled influence of temperature and moisture is greater than a mere combination of their individual influences.
Environmental effects on long term behavior of composite laminates
NASA Technical Reports Server (NTRS)
Singhal, S. N.; Chamis, C. C.
1992-01-01
Model equations are presented for approximate methods simulating the long-term behavior of composite materials and structures in hot/humid service environments. These equations allow laminate property upgradings with time, and can account for the effects of service environments on creep response. These methodologies are illustrated for various individual and coupled temperature/moisture, longitudinal/transverse, and composite material type cases. Creep deformation is noted to rise dramatically for cases of matrix-borne, but not of fiber-borne, loading in hot, humid environments; the coupled influence of temperature and moisture is greater than a mere combination of their individual influences.
ERIC Educational Resources Information Center
Gardner, Lara; Gilleskie, Donna B.
2012-01-01
Medicaid policies that may affect long-term care decisions vary across states and time. Using data from the 1993, 1995, 1998, and 2000 waves of the Assets and Health Dynamics Among the Oldest Old Survey, we estimate a dynamic empirical model of health insurance coverage, long-term care arrangement, asset and gift behavior, and health transitions…
Rahn, Elizabeth J; Guzman-Karlsson, Mikael C; David Sweatt, J
2013-10-01
Sensitization is a form of non-associative conditioning in which amplification of behavioral responses can occur following presentation of an aversive or noxious stimulus. Understanding the cellular and molecular underpinnings of sensitization has been an overarching theme spanning the field of learning and memory as well as that of pain research. In this review we examine how sensitization, both in the context of learning as well as pain processing, shares evolutionarily conserved behavioral, cellular/synaptic, and epigenetic mechanisms across phyla. First, we characterize the behavioral phenomenon of sensitization both in invertebrates and vertebrates. Particular emphasis is placed on long-term sensitization (LTS) of withdrawal reflexes in Aplysia following aversive stimulation or injury, although additional invertebrate models are also covered. In the context of vertebrates, sensitization of mammalian hyperarousal in a model of post-traumatic stress disorder (PTSD), as well as mammalian models of inflammatory and neuropathic pain is characterized. Second, we investigate the cellular and synaptic mechanisms underlying these behaviors. We focus our discussion on serotonin-mediated long-term facilitation (LTF) and axotomy-mediated long-term hyperexcitability (LTH) in reduced Aplysia systems, as well as mammalian spinal plasticity mechanisms of central sensitization. Third, we explore recent evidence implicating epigenetic mechanisms in learning- and pain-related sensitization. This review illustrates the fundamental and functional overlay of the learning and memory field with the pain field which argues for homologous persistent plasticity mechanisms in response to sensitizing stimuli or injury across phyla. Copyright © 2013 Elsevier Inc. All rights reserved.
Wilde, Mary H.; Crean, Hugh F.; McMahon, James M.; McDonald, Margaret V.; Tang, Wan; Brasch, Judith; Fairbanks, Eileen; Shah, Shivani; Zhang, Feng
2015-01-01
Background Urinary tract infection and blockage are serious and recurrent challenges for people with long-term indwelling catheters, and these catheter problems cause worry and anxiety when they disrupt normal daily activities. Objectives The goal was to determine whether urinary catheter-related self-management behaviors focusing on fluid intake would mediate fluid intake related self-efficacy toward decreasing catheter-associated urinary tract infection (CAUTI) and/or catheter blockage. Method The sample involved data collected from 180 adult community-living, long-term indwelling urinary catheter users. The authors tested a model of fluid intake self-management (F-SMG) related to fluid intake self-efficacy (F-SE) for key outcomes of CAUTI and blockage. To account for the large number of zeros in both outcomes, a zero inflated negative binomial (ZINB) structural equation model was tested. Results Structurally, F-SE was positively associated with F-SMG, suggesting that higher F-SE predicts more (higher) F-SMG; however, F-SMG was not associated with either the frequency of CAUTI’s or the presence or absence of CAUTI. F-SE was positively related to F-SMG and F-SMG predicted less frequency of catheter blockage, but neither F-SE nor F-SMG predicted the presence or absence of blockage. Discussion Further research is needed to better understand determinants of CAUTI in long-term catheter users and factors which might influence or prevent its occurrence. Increased confidence (self-efficacy) and self-management behaviors to promote fluid intake could be of value in long-term urinary catheter users to decrease catheter blockage. PMID:26938358
Anxiolytic effects of GLYX-13 in animal models of posttraumatic stress disorder-like behavior.
Jin, Zeng-Liang; Liu, Jin-Xu; Liu, Xu; Zhang, Li-Ming; Ran, Yu-Hua; Zheng, Yuan-Yuan; Tang, Yu; Li, Yun-Feng; Xiong, Jie
2016-09-01
In the present study, we investigated the effectiveness of GLYX-13, an NMDA receptor glycine site functional partial agonist, to alleviate the enhanced anxiety and fear response in both a mouse and rat model of stress-induced behavioral changes that might be relevant to posttraumatic stress disorder (PTSD). Studies over the last decades have suggested that the hyperactivity of hypothalamic-pituitary-adrenal (HPA) axis is one of the most consistent findings in stress-related disease. Herein, we used these animal models to further investigate the effect of GLYX-13 on the stress hormone levels and glucocorticoid receptor (GR) expression. We found that exposure to foot shock induced long-lasting behavioral deficiencies in mice, including freezing and anxiety-like behaviors, that were significantly ameliorated by the long-term administration of GLYX-13 (5 or 10 mg/kg). Our enzyme-linked immunosorbent assay results showed that long-term administration of GLYX-13 at behaviorally effective doses (5 or 10 mg/kg) significantly decreased the elevated serum levels of both corticosterone and its upstream stress hormone adrenocorticotropic hormone in rats subjected to the TDS procedure. These results suggest that GLYX-13 exerts a therapeutic effect on PTSD-like stress responding that is accompanied by (or associated with) modulation of the HPA axis, including inhibition of stress hormone levels and upregulation of hippocampal GR expression. © The Author(s) 2016.
Water Absorption Behavior of Hemp Hurds Composites
Stevulova, Nadezda; Cigasova, Julia; Purcz, Pavol; Schwarzova, Ivana; Kacik, Frantisek; Geffert, Anton
2015-01-01
In this paper, water sorption behavior of 28 days hardened composites based on hemp hurds and inorganic binder was studied. Two kinds of absorption tests on dried cube specimens in deionized water bath at laboratory temperature were performed. Short-term (after one hour water immersion) and long-term (up to 180 days) water absorption tests were carried out to study their durability. Short-term water sorption behavior of original hemp hurds composites depends on mean particle length of hemp and on binder nature. The comparative study of long-term water sorption behavior of composites reinforced with original and chemically modified hemp hurds in three reagents confirmed that surface treatment of filler influences sorption process. Based on evaluation of sorption curves using a model for composites based on natural fibers, diffusion of water molecules in composite reinforced with original and chemically modified hemp hurds is anomalous in terms of the Fickian behavior. The most significant decrease in hydrophility of hemp hurds was found in case of hemp hurds modified by NaOH and it relates to change in the chemical composition of hemp hurds, especially to a decrease in average degree of cellulose polymerization as well as hemicellulose content.
Intelligent Planning and Scheduling for Controlled Life Support Systems
NASA Technical Reports Server (NTRS)
Leon, V. Jorge
1996-01-01
Planning in Controlled Ecological Life Support Systems (CELSS) requires special look ahead capabilities due to the complex and long-term dynamic behavior of biological systems. This project characterizes the behavior of CELSS, identifies the requirements of intelligent planning systems for CELSS, proposes the decomposition of the planning task into short-term and long-term planning, and studies the crop scheduling problem as an initial approach to long-term planning. CELSS is studied in the realm of Chaos. The amount of biomass in the system is modeled using a bounded quadratic iterator. The results suggests that closed ecological systems can exhibit periodic behavior when imposed external or artificial control. The main characteristics of CELSS from the planning and scheduling perspective are discussed and requirements for planning systems are given. Crop scheduling problem is identified as an important component of the required long-term lookahead capabilities of a CELSS planner. The main characteristics of crop scheduling are described and a model is proposed to represent the problem. A surrogate measure of the probability of survival is developed. The measure reflects the absolute deviation of the vital reservoir levels from their nominal values. The solution space is generated using a probability distribution which captures both knowledge about the system and the current state of affairs at each decision epoch. This probability distribution is used in the context of an evolution paradigm. The concepts developed serve as the basis for the development of a simple crop scheduling tool which is used to demonstrate its usefulness in the design and operation of CELSS.
Chang, Yao-Feng; Fowler, Burt; Chen, Ying-Chen; Zhou, Fei; Pan, Chih-Hung; Chang, Ting-Chang; Lee, Jack C.
2016-01-01
We realize a device with biological synaptic behaviors by integrating silicon oxide (SiOx) resistive switching memory with Si diodes. Minimal synaptic power consumption due to sneak-path current is achieved and the capability for spike-induced synaptic behaviors is demonstrated, representing critical milestones for the use of SiO2–based materials in future neuromorphic computing applications. Biological synaptic behaviors such as long-term potentiation (LTP), long-term depression (LTD) and spike-timing dependent plasticity (STDP) are demonstrated systematically using a comprehensive analysis of spike-induced waveforms, and represent interesting potential applications for SiOx-based resistive switching materials. The resistive switching SET transition is modeled as hydrogen (proton) release from (SiH)2 to generate the hydrogen bridge defect, and the RESET transition is modeled as an electrochemical reaction (proton capture) that re-forms (SiH)2. The experimental results suggest a simple, robust approach to realize programmable neuromorphic chips compatible with large-scale CMOS manufacturing technology. PMID:26880381
NASA Astrophysics Data System (ADS)
Chang, Yao-Feng; Fowler, Burt; Chen, Ying-Chen; Zhou, Fei; Pan, Chih-Hung; Chang, Ting-Chang; Lee, Jack C.
2016-02-01
We realize a device with biological synaptic behaviors by integrating silicon oxide (SiOx) resistive switching memory with Si diodes. Minimal synaptic power consumption due to sneak-path current is achieved and the capability for spike-induced synaptic behaviors is demonstrated, representing critical milestones for the use of SiO2-based materials in future neuromorphic computing applications. Biological synaptic behaviors such as long-term potentiation (LTP), long-term depression (LTD) and spike-timing dependent plasticity (STDP) are demonstrated systematically using a comprehensive analysis of spike-induced waveforms, and represent interesting potential applications for SiOx-based resistive switching materials. The resistive switching SET transition is modeled as hydrogen (proton) release from (SiH)2 to generate the hydrogen bridge defect, and the RESET transition is modeled as an electrochemical reaction (proton capture) that re-forms (SiH)2. The experimental results suggest a simple, robust approach to realize programmable neuromorphic chips compatible with large-scale CMOS manufacturing technology.
The Mars water cycle at other epochs - Recent history of the polar caps and layered terrain
NASA Technical Reports Server (NTRS)
Jakosky, Bruce M.; Henderson, Bradley G.; Mellon, Michael T.
1993-01-01
A numerical model is presented of the integrated role of seasonal water cycle on the evolution of polar deposits on Mars over the last 10 million years. From the model, it is concluded that the only major difference between the polar caps which affects their long-term behavior is ultimately the difference in their elevations. Because of that difference, there is a preference for CO2 frost to stay longer on the northern polar cap. The average difference in sublimation at the caps results in a net south-to-north transport of water ice over long time scales. Superimposed on any long-term behavior is a transfer of water ice between the caps on the 10 exp 5 - 10 exp 6 yr time scales. The amount of water exchanged is small compared to the total ice content of the polar deposits.
The Mars water cycle at other epochs - Recent history of the polar caps and layered terrain
NASA Astrophysics Data System (ADS)
Jakosky, B. M.; Henderson, B. G.; Mellon, M. T.
1993-04-01
A numerical model is presented of the integrated role of seasonal water cycle on the evolution of polar deposits on Mars over the last 10 million years. From the model, it is concluded that the only major difference between the polar caps which affects their long-term behavior is ultimately the difference in their elevations. Because of that difference, there is a preference for CO2 frost to stay longer on the northern polar cap. The average difference in sublimation at the caps results in a net south-to-north transport of water ice over long time scales. Superimposed on any long-term behavior is a transfer of water ice between the caps on the 10 exp 5 - 10 exp 6 yr time scales. The amount of water exchanged is small compared to the total ice content of the polar deposits.
The Effects of Early-Life Predator Stress on Anxiety- and Depression-Like Behaviors of Adult Rats
Chen, Lu-jing; Shen, Bing-qing; Liu, Dan-dan; Li, Sheng-tian
2014-01-01
Childhood emotional trauma contributes significantly to certain psychopathologies, such as post-traumatic stress disorder. In experimental animals, however, whether or not early-life stress results in behavioral abnormalities in adult animals still remains controversial. Here, we investigated both short-term and long-term changes of anxiety- and depression-like behaviors of Wistar rats after being exposed to chronic feral cat stress in juvenile ages. The 2-week predator stress decreased spontaneous activities immediately following stress but did not increase depression- or anxiety-like behaviors 4 weeks after the stimulation in adulthood. Instead, juvenile predator stress had some protective effects, though not very obvious, in adulthood. We also exposed genetic depression model rats, Wistar Kyoto (WKY) rats, to the same predator stress. In WKY rats, the same early-life predator stress did not enhance anxiety- or depression-like behaviors in both the short-term and long-term. However, the stressed WKY rats showed slightly reduced depression-like behaviors in adulthood. These results indicate that in both normal Wistar rats and WKY rats, early-life predator stress led to protective, rather than negative, effects in adulthood. PMID:24839560
Creep model of unsaturated sliding zone soils and long-term deformation analysis of landslides
NASA Astrophysics Data System (ADS)
Zou, Liangchao; Wang, Shimei; Zhang, Yeming
2015-04-01
Sliding zone soil is a special soil layer formed in the development of a landslide. Its creep behavior plays a significant role in long-term deformation of landslides. Due to rainfall infiltration and reservoir water level fluctuation, the soils in the slide zone are often in unsaturated state. Therefore, the investigation of creep behaviors of the unsaturated sliding zone soils is of great importance for understanding the mechanism of the long-term deformation of a landslide in reservoir areas. In this study, the full-process creep curves of the unsaturated soils in the sliding zone in different net confining pressure, matric suctions and stress levels were obtained from a large number of laboratory triaxial creep tests. A nonlinear creep model for unsaturated soils and its three-dimensional form was then deduced based on the component model theory and unsaturated soil mechanics. This creep model was validated with laboratory creep data. The results show that this creep model can effectively and accurately describe the nonlinear creep behaviors of the unsaturated sliding zone soils. In order to apply this creep model to predict the long-term deformation process of landslides, a numerical model for simulating the coupled seepage and creep deformation of unsaturated sliding zone soils was developed based on this creep model through the finite element method (FEM). By using this numerical model, we simulated the deformation process of the Shuping landslide located in the Three Gorges reservoir area, under the cycling reservoir water level fluctuation during one year. The simulation results of creep displacement were then compared with the field deformation monitoring data, showing a good agreement in trend. The results show that the creeping deformations of landslides have strong connections with the changes of reservoir water level. The creep model of unsaturated sliding zone soils and the findings obtained by numerical simulations in this study are conducive to reveal the mechanisms of the dynamic process of landslide deformation, and serve as an important basis for the prediction and evaluation of landslides.
Waddell, Jaylyn; Hanscom, Marie; Edwards, N. Shalon; McKenna, Mary C.; McCarthy, Margaret M.
2015-01-01
Hypoxia ischemia (HI) of the brain in near-term and term infants is a leading cause of infant mortality and lifelong disability but current therapeutic approaches remain limited. Males consistently display greater vulnerability to the deleterious consequences of HI in both humans and animal models. Neurogenesis increases after neonatal HI and offers a potential therapeutic target for recovery. The steroid hormone estradiol has been extensively explored as a neuroprotectant in adult models of stroke but with mixed results. Less consideration has been afforded to this naturally occurring agent in the developing brain, which has unique challenges from the adult. Using a model of term HI in the rat we have explored the impact of this insult on cell genesis in the hippocampus of males and females and the ability of estradiol treatment immediately after insult to restore function. Both short-term (3 days) and long-term (7 days) post-injury were assessed and revealed that only females had markedly increased cell genesis on the short-term but both sexes were increased long-term. A battery of behavioral tests revealed motor impairment in males and compromised episodic memory while both sexes were modestly impaired in spatial memory. Juvenile social play was also depressed in both sexes after HI. Estradiol therapy improved behavioral performance in both sexes but did not reverse a deficit in hippocampal volume ipsilateral to the insult. Thus the effects of estradiol do not appear to be via cell death or proliferation but rather involve other components of neural functioning. PMID:26376217
Waddell, Jaylyn; Hanscom, Marie; Shalon Edwards, N; McKenna, Mary C; McCarthy, Margaret M
2016-01-01
Hypoxia-ischemia (HI) of the brain in near-term and term infants is a leading cause of infant mortality and lifelong disability but current therapeutic approaches remain limited. Males consistently display greater vulnerability to the deleterious consequences of HI in both humans and animal models. Neurogenesis increases after neonatal HI and offers a potential therapeutic target for recovery. The steroid hormone estradiol has been extensively explored as a neuroprotectant in adult models of stroke but with mixed results. Less consideration has been afforded to this naturally occurring agent in the developing brain, which has unique challenges from the adult. Using a model of term HI in the rat we have explored the impact of this insult on cell genesis in the hippocampus of males and females and the ability of estradiol treatment immediately after insult to restore function. Both short-term (3 days) and long-term (7 days) post-injury were assessed and revealed that only females had markedly increased cell genesis on the short-term but both sexes were increased long-term. A battery of behavioral tests revealed motor impairment in males and compromised episodic memory while both sexes were modestly impaired in spatial memory. Juvenile social play was also depressed in both sexes after HI. Estradiol therapy improved behavioral performance in both sexes but did not reverse a deficit in hippocampal volume ipsilateral to the insult. Thus the effects of estradiol do not appear to be via cell death or proliferation but rather involve other components of neural functioning. Published by Elsevier Inc.
Osier, Nicole D.; Carlson, Shaun W.; DeSana, Anthony
2015-01-01
Abstract The purpose of this review is to survey the use of experimental animal models for studying the chronic histopathological and behavioral consequences of traumatic brain injury (TBI). The strategies employed to study the long-term consequences of TBI are described, along with a summary of the evidence available to date from common experimental TBI models: fluid percussion injury; controlled cortical impact; blast TBI; and closed-head injury. For each model, evidence is organized according to outcome. Histopathological outcomes included are gross changes in morphology/histology, ventricular enlargement, gray/white matter shrinkage, axonal injury, cerebrovascular histopathology, inflammation, and neurogenesis. Behavioral outcomes included are overall neurological function, motor function, cognitive function, frontal lobe function, and stress-related outcomes. A brief discussion is provided comparing the most common experimental models of TBI and highlighting the utility of each model in understanding specific aspects of TBI pathology. The majority of experimental TBI studies collect data in the acute postinjury period, but few continue into the chronic period. Available evidence from long-term studies suggests that many of the experimental TBI models can lead to progressive changes in histopathology and behavior. The studies described in this review contribute to our understanding of chronic TBI pathology. PMID:25490251
Hsueh, Shih-Chang; Lai, Jing-Huei; Wu, Chung-Che; Yu, Yu-Wen; Luo, Yu; Hsieh, Tsung-Hsun; Chiang, Yung-Hsiao
2018-01-01
Background: Parkinson’s disease (PD) is typically characterized by impairment of motor function. Gait disturbances similar to those observed in patients with PD can be observed in animals after injection of neurotoxin 6-hydroxydopamine (6-OHDA) to induce unilateral nigrostriatal dopamine depletion. Exercise has been shown to be a promising non-pharmacological approach to reduce the risk of neurodegenerative disease. Methods: In this study, we investigated the long-term effects of voluntary running wheel exercise on gait phenotypes, depression, cognitive, rotational behaviors as well as histology in a 6-OHDA-lesioned rat model of PD. Results: We observed that, when compared with the non-exercise controls, five-week voluntary exercise alleviated and postponed the 6-OHDA-induced gait deficits, including a significantly improved walking speed, step/stride length, base of support and print length. In addition, we found that the non-motor functions, such as novel object recognition and forced swim test, were also ameliorated by voluntary exercise. However, the rotational behavior of the exercise group did not show significant differences when compared with the non-exercise group. Conclusions: We first analyzed the detailed spatiotemporal changes of gait pattern to investigate the potential benefits after long-term exercise in the rat model of PD, which could be useful for future objective assessment of locomotor function in PD or other neurological animal models. Furthermore, these results suggest that short-term voluntary exercise is sufficient to alleviate cognition deficits and depressive behavior in 6-OHDA lesioned rats and long-term treatment reduces the progression of motor symptoms and elevates tyrosine hydroxylase (TH), Brain-derived neurotrophic factor (BDNF), bone marrow tyrosine kinase in chromosome X (BMX) protein expression level without affecting dopaminergic (DA) neuron loss in this PD rat model. PMID:29419747
Baum, William M.
1995-01-01
Behavior analysis risks intellectual isolation unless it integrates its explanations with evolutionary theory. Rule-governed behavior is an example of a topic that requires an evolutionary perspective for a full understanding. A rule may be defined as a verbal discriminative stimulus produced by the behavior of a speaker under the stimulus control of a long-term contingency between the behavior and fitness. As a discriminative stimulus, the rule strengthens listener behavior that is reinforced in the short run by socially mediated contingencies, but which also enters into the long-term contingency that enhances the listener's fitness. The long-term contingency constitutes the global context for the speaker's giving the rule. When a rule is said to be “internalized,” the listener's behavior has switched from short- to long-term control. The fitness-enhancing consequences of long-term contingencies are health, resources, relationships, or reproduction. This view ties rules both to evolutionary theory and to culture. Stating a rule is a cultural practice. The practice strengthens, with short-term reinforcement, behavior that usually enhances fitness in the long run. The practice evolves because of its effect on fitness. The standard definition of a rule as a verbal statement that points to a contingency fails to distinguish between a rule and a bargain (“If you'll do X, then I'll do Y”), which signifies only a single short-term contingency that provides mutual reinforcement for speaker and listener. In contrast, the giving and following of a rule (“Dress warmly; it's cold outside”) can be understood only by reference also to a contingency providing long-term enhancement of the listener's fitness or the fitness of the listener's genes. Such a perspective may change the way both behavior analysts and evolutionary biologists think about rule-governed behavior. ImagesFigure 1 PMID:22478201
Middelkamp, Jan; van Rooijen, Maaike; Wolfhagen, Peter; Steenbergen, Bert
2017-01-01
The transtheoretical model of behavior change (TTM) is often used to understand changes in health-related behavior, like exercise. Exercise behavior in fitness clubs is an understudied topic, but preliminary studies showed low frequencies and large numbers of drop-out. An initial 12-week self-efficacy intervention reported significant effects on exercise behavior. The objective of this follow up study is testing effects on exercise behavior over 52 weeks and the long-term relationships of all TTM constructs. In total 122 participants (Mage 42.02 yr.; SD 12.29; 67% females) were recruited and randomly assigned to group 1 (control), group 2 (self-set activities) and group 3 (self-set goals coaching). All participants were monitored 52-weeks. Measurements at baseline, 4, 8, 12, 26 and 52 weeks, using validated scales for stages of change, self-efficacy, decisional balance and processes of change. Exercise behavior and drop-outs were registered. An ANOVA revealed that group 3 significantly (p < 0.05) differed in exercise sessions from group 1 and 2 during the 12 weeks. A chi-square test indicated significant differences for continuing exercising after the intervention: 7 of group 1; 6 of group 2; 19 of group 3. In total 5 demonstrated regular exercise behavior at 26 weeks, and 3 at 52 weeks. Self-efficacy, decisional balance, and processes of change showed limited long-term changes over the later stages of change. At all measurements, participants reported more pros than cons and used more behavioral than cognitive processes. Exercise behavior of members in fitness clubs demonstrated dramatic developments in 52 weeks. The frequencies of sessions were so low that health effects will be minimal. The integrative character of the TTM appears to be weak; the data indicated limited relationships. More research is needed to understand exercise behavior and define optimal strategies to increase exercise attendance and decrease drop-outs in the long term. Key points Approximately 151 million individuals exercise in 187.000 fitness clubs worldwide, mainly for health benefits. The transtheoretical model of behavior change is often used to understand changes in health-related behavior, like exercise, but was never applied to this understudied population. An initial 12-week self-efficacy intervention reported significant effects on (increased) exercise behavior. The effects of this intervention were diminished at 26 and 52 weeks, with respectively only five and three participants maintaining regular exercise behavior in fitness clubs. The integrative character of the TTM in this population appears to be weak; the data indicated limited relationships. PMID:28630568
1998-07-01
Communications Objectives Measurement System (ACOMS)." The utility of the Fishbein and Ajzen theories of reasoned action within the context of military...conceptual model that applied the Fishbein and Ajzen concepts to enlistment intentions and behaviors, through an exploratory analysis of the variables...first-term Army enlisted attrition. In support of this long-term effort, ASA M &RA sponsored Phase I of a research program modeled after ARI’s broad
Long Term Degradation of Resin for High Temperature Composites
NASA Technical Reports Server (NTRS)
Patekar, Kaustubh A.
2000-01-01
The durability of polymer matrix composites exposed to harsh environments is a major concern. Surface degradation and damage are observed in polyimide composites used in air at 125 to 300 C. It is believed that diffusion of oxygen into the material and oxidative chemical reactions in the matrix are responsible. Previous work has characterized and modeled diffusion behavior, and thermogravimetric analyses (TGAs) have been carried out in nitrogen, air, and oxygen to provide quantitative information on thermal and oxidative reactions. However, the model developed using these data was not able to capture behavior seen in isothermal tests, especially those of long duration. A test program that focuses on lower temperatures and makes use of isothermal tests was undertaken to achieve a better understanding of the degradation reactions under use conditions. A new low-cost technique was developed to collect chemical degradation data for isothermal tests lasting over 200 hr in the temperature range 125 to 300 C. Results indicate complex behavior not captured by the previous TGA tests, including the presence of weight-adding reactions. Weight gain reactions dominated in the 125 to 225 C temperature range, while weight loss reactions dominated beyond 225 C. The data obtained from isothermal tests was used to develop a new model of the material behavior. This model was able to fully capture the behavior seen in the tests up to 275 C. Correlation of the current model with both isothermal data at 300 C and high rate TGA test data is mediocre. At 300 C and above, the reaction mechanisms appear to change. Attempts (which failed) to measure non-oxidative degradation indicate that oxidative reactions dominate the degradation at low temperatures. Based on this work, long term isothermal testing in an oxidative atmosphere is recommended for studying the degradation behavior of this class of materials.
Blue Whale Behavioral Response Study and Field Testing of the New Bioacoustic Probe
2011-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Blue Whale Behavioral Response Study & Field Testing of...6849 email: jhildebrand@ucsd.edu Award Number: N000140811221 LONG-TERM GOALS Task 1: Blue Whales Behavioral Response Study The...behavioral response of large whales to commercial shipping and other low-frequency anthropogenic sound is not well understood. The PCAD model (NRC 2005
ERIC Educational Resources Information Center
Schulz, Kristina; Korz, Volker
2010-01-01
Emotionality as well as cognitive abilities contribute to the acquisition and retrieval of memories as well as to the consolidation of long-term potentiation (LTP), a cellular model of memory formation. However, little is known about the timescale and relative contribution of these processes. Therefore, we tested the effects of weak water maze…
The Precession Index and a Nonlinear Energy Balance Climate Model
NASA Technical Reports Server (NTRS)
Rubincam, David
2004-01-01
A simple nonlinear energy balance climate model yields a precession index-like term in the temperature. Despite its importance in the geologic record, the precession index e sin (Omega)S, where e is the Earth's orbital eccentricity and (Omega)S is the Sun's perigee in the geocentric frame, is not present in the insolation at the top of the atmosphere. Hence there is no one-for-one mapping of 23,000 and 19,000 year periodicities from the insolation to the paleoclimate record; a nonlinear climate model is needed to produce these long periods. A nonlinear energy balance climate model with radiative terms of form T n, where T is surface temperature and n less than 1, does produce e sin (omega)S terms in temperature; the e sin (omega)S terms are called Seversmith psychroterms. Without feedback mechanisms, the model achieves extreme values of 0.64 K at the maximum orbital eccentricity of 0.06, cooling one hemisphere while simultaneously warming the other; the hemisphere over which perihelion occurs is the cooler. In other words, the nonlinear energy balance model produces long-term cooling in the northern hemisphere when the Sun's perihelion is near northern summer solstice and long-term warming in the northern hemisphere when the aphelion is near northern summer solstice. (This behavior is similar to the inertialess gray body which radiates like T 4, but the amplitude is much lower for the energy balance model because of its thermal inertia.) This seemingly paradoxical behavior works against the standard Milankovitch model, which requires cool northern summers (Sun far from Earth in northern summer) to build up northern ice sheets, so that if the standard model is correct it must be more efficient than previously thought. Alternatively, the new mechanism could possibly be dominant and indicate southern hemisphere control of the northern ice sheets, wherein the southern oceans undergo a long-term cooling when the Sun is far from the Earth during northern summer. The cold water eventually flows north, cooling the northern hemisphere. This might explain why the northern oceans lag the southern ones when it comes to orbital forcing.
BEHAVIORAL ASSESSMENTS OF LONG EVANS RATS FOLLOWING A 13 WEEK SUBCHRONIC TOLUENE EXPOSURE.
Whereas the acute effects of volatile organic compounds (VOCs) are relatively well understood, there is some controversy regarding the potential for persistent effects following long-term exposure. The current study sought to develop an animal model of subchronic exposure to VOCs...
Flexural creep behaviour of jute polypropylene composites
NASA Astrophysics Data System (ADS)
Chandekar, Harichandra; Chaudhari, Vikas
2016-09-01
Present study is about the flexural creep behaviour of jute fabric reinforced polypropylene (Jute-PP) composites. The PP sheet and alkali treated jute fabric is stacked alternately and hot pressed in compression molding machine to get Jute-PP composite laminate. The flexural creep study is carried out on dynamic mechanical analyzer. The creep behaviour of the composite is modeled using four-parameter Burgers model. Short-term accelerated creep testing is conducted which is later used to predict long term creep behaviour. The feasibility of the construction of a master curve using the time-temperature superposition (TTS) principle to predict long term creep behavior of unreinforced PP and Jute-PP composite is investigated.
Roy, Nicole M.; Arpie, Brianna; Lugo, Joseph; Linney, Elwood; Levin, Edward D.; Cerutti, Daniel
2015-01-01
Zebrafish provide a powerful model of the impacts of embryonic toxicant exposure on neural development that may result in long-term behavioral dysfunction. In this study, zebrafish embryos were treated with 1.5 mM strychnine for short embryonic time windows to induce transient changes in inhibitory neural signaling, and were subsequently raised in untreated water until adulthood. PCR analysis showed indications that strychnine exposure altered expression of some genes related to glycinergic, GABAergic and glutamatergic neuronal synapses during embryonic development. In adulthood, treated fish showed significant changes in swimming speed and tank diving behavior compared to controls. Taken together, these data show that a short embryonic exposure to a neurotoxicant can alter development of neural synapses and lead to changes in adult behavior. PMID:23022260
Roy, Nicole M; Arpie, Brianna; Lugo, Joseph; Linney, Elwood; Levin, Edward D; Cerutti, Daniel
2012-01-01
Zebrafish provide a powerful model of the impacts of embryonic toxicant exposure on neural development that may result in long-term behavioral dysfunction. In this study, zebrafish embryos were treated with 1.5mM strychnine for short embryonic time windows to induce transient changes in inhibitory neural signaling, and were subsequently raised in untreated water until adulthood. PCR analysis showed indications that strychnine exposure altered expression of some genes related to glycinergic, GABAergic and glutamatergic neuronal synapses during embryonic development. In adulthood, treated fish showed significant changes in swimming speed and tank diving behavior compared to controls. Taken together, these data show that a short embryonic exposure to a neurotoxicant can alter development of neural synapses and lead to changes in adult behavior. Copyright © 2012 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Sierhuis, Maarten; Clancey, William J.; Damer, Bruce; Brodsky, Boris; vanHoff, Ron
2007-01-01
A virtual worlds presentation technique with embodied, intelligent agents is being developed as an instructional medium suitable to present in situ training on long term space flight. The system combines a behavioral element based on finite state automata, a behavior based reactive architecture also described as subsumption architecture, and a belief-desire-intention agent structure. These three features are being integrated to describe a Brahms virtual environment model of extravehicular crew activity which could become a basis for procedure training during extended space flight.
Davenport, Matthew D.; Lutz, Corrine K.; Tiefenbacher, Stefan; Novak, Melinda A.; Meyer, Jerrold S.
2008-01-01
Background Self-injurious behavior (SIB), a disorder that afflicts many individuals within both clinical and non-clinical populations, has been linked to states of heightened stress and arousal. However, there are no published longitudinal data on the relationship between increases in stress and changes in the incidence of SIB. The present study investigated the short- and long-term behavioral and neuroendocrine responses of SIB and control monkeys to the stress of relocation. Methods Twenty adult male rhesus macaques were exposed to the stress of relocation to a new housing arrangement in a newly constructed facility. Daytime behavior, sleep, and multiple measures of hypothalamic-pituitary-adrenocortical (HPA) axis function were investigated before and after the move. Results Relocation induced a complex pattern of short- and long-term effects in the animals. The SIB animals showed a long-lasting increase in self-biting behavior as well as evidence of sleep disturbance. Both groups exhibited elevated cortisol levels in saliva, serum, and hair, and also an unexpected delayed increase in circulating concentrations of corticosteroid binding globulin (CBG). Conclusions Our results indicate that relocation is a significant stressor for rhesus macaques, and that this stressor triggers an increase in self-biting behavior as well as sleep disturbance in monkeys previously identified as suffering from SIB. These findings suggest that life stresses may similarly exacerbate SIB in humans with this disorder. The HPA axis results underscore the potential role of CBG in regulating long-term neuroendocrine responses to major stressors. PMID:18164279
Phospholipase A₂: the key to reversing long-term memory impairment in a gastropod model of aging.
Watson, Shawn N; Wright, Natasha; Hermann, Petra M; Wildering, Willem C
2013-02-01
Memory failure associated with changes in neuronal circuit functions rather than cell death is a common feature of normal aging in diverse animal species. The (neuro)biological foundations of this phenomenon are not well understood although oxidative stress, particularly in the guise of lipid peroxidation, is suspected to play a key role. Using an invertebrate model system of age-associated memory impairment that supports direct correlation between behavioral deficits and changes in the underlying neural substrate, we show that inhibition of phospholipase A(2) (PLA(2)) abolishes both long-term memory (LTM) and neural defects observed in senescent subjects and subjects exposed to experimental oxidative stress. Using a combination of behavioral assessments and electrophysiological techniques, we provide evidence for a close link between lipid peroxidation, provocation of phospholipase A(2)-dependent free fatty acid release, decline of neuronal excitability, and age-related long-term memory impairments. This supports the view that these processes suspend rather than irreversibly extinguish the aging nervous system's intrinsic capacity for plasticity. Copyright © 2013 Elsevier Inc. All rights reserved.
Forecasting client transitions in British Columbia's Long-Term Care Program.
Lane, D; Uyeno, D; Stark, A; Gutman, G; McCashin, B
1987-01-01
This article presents a model for the annual transitions of clients through various home and facility placements in a long-term care program. The model, an application of Markov chain analysis, is developed, tested, and applied to over 9,000 clients (N = 9,483) in British Columbia's Long Term Care Program (LTC) over the period 1978-1983. Results show that the model gives accurate forecasts of the progress of groups of clients from state to state in the long-term care system from time of admission until eventual death. Statistical methods are used to test the modeling hypothesis that clients' year-over-year transitions occur in constant proportions from state to state within the long-term care system. Tests are carried out by examining actual year-over-year transitions of each year's new admission cohort (1978-1983). Various subsets of the available data are analyzed and, after accounting for clear differences among annual cohorts, the most acceptable model of the actual client transition data occurred when clients were separated into male and female groups, i.e., the transition behavior of each group is describable by a different Markov model. To validate the model, we develop model estimates for the numbers of existing clients in each state of the long-term care system for the period (1981-1983) for which actual data are available. When these estimates are compared with the actual data, total weighted absolute deviations do not exceed 10 percent of actuals. Finally, we use the properties of the Markov chain probability transition matrix and simulation methods to develop three-year forecasts with prediction intervals for the distribution of the existing total clients into each state of the system. The tests, forecasts, and Markov model supplemental information are contained in a mechanized procedure suitable for a microcomputer. The procedure provides a powerful, efficient tool for decision makers planning facilities and services in response to the needs of long-term care clients. PMID:3121537
BEHAVIORAL ASSESSMENTS OF LONG EVANS RATS FOLLOWING A 13-WEEK SUBCHRONIC TOLUENE EXPOSURE.
The current study sought to develop an animal model of the neurotoxicity of long-term exposure to volatile organic compounds (VOCs) which may be used to predict the effects of chronic exposure to VOCs on public health. The effects of Subchronic inhalation exposure to toluene (0,...
Wolf, M M; Braukmann, C J; Ramp, K A
1987-01-01
The past 20 years have been productive ones for the field of applied behavior analysis. A brief review of our own efforts during this period reveals that we have accomplished several but not all of our goals for the Teaching-Family approach. In this context, we note that the setting of realistic and appropriate goals is important for the field and for society. Moreover, we suggest that the realistic goal for some persons with serious delinquent behavior may be extended supportive and socializing treatment rather than permanent cure from conventional short-term treatment programs. We base this suggestion on the accumulating evidence that serious delinquent behavior may often be part of a significantly disabling and durable condition that consists of multiple antisocial and dysfunctional behaviors, often runs in families, and robustly eludes effective short-term treatment. Like other significant disabilities such as retardation, autism, and blindness, the effects of this condition may be a function of an interaction of environmental and constitutional variables. We argue that our field has the wherewithal to construct effective and humane long-term supportive environments for seriously delinquent youths. In this regard, we explore the dimensions, rationales, logistics, and beginnings of a new treatment direction that involves long-term supportive family treatment. We contend that such supportive families may be able to provide long, perhaps even lifetime, socializing influences through models, values, and contingencies that seem essential for developing and maintaining prosocial behavior in these high-risk youths. PMID:3323156
Long-term transport behavior of psychoactive compounds in sewage-affected groundwater
NASA Astrophysics Data System (ADS)
Nham, Hang Thuy Thi; Greskowiak, Janek; Hamann, Enrico; Meffe, Raffaella; Hass, Ulrike; Massmann, Gudrun
2016-11-01
The present study provides a model-based characterization of the long-term transport behavior of five psychoactive compounds (meprobamate, pyrithyldione, primidone, phenobarbital and phenylethylmalonamide) introduced into groundwater via sewage irrigation in Berlin, Germany. Compounds are still present in the groundwater despite the sewage farm closure in the year 1980. Due to the limited information on (i) compound concentrations in the source water and (ii) substance properties, a total of 180 cross-sectional model realizations for each compound were carried out, covering a large range of possible parameter combinations. Results were compared with the present-day contamination patterns in the aquifer and the most likely scenarios were identified based on a number of model performance criteria. The simulation results show that (i) compounds are highly persistent under the present field conditions, and (ii) sorption is insignificant. Thus, back-diffusion from low permeability zones appears as the main reason for the compound retardation.
Drought, water conservation, and water demand rebound in California
NASA Astrophysics Data System (ADS)
Gonzales, P.; Ajami, N.
2017-12-01
There is growing recognition that dynamic community values, preferences, and water use behaviors are important drivers of water demand in addition to external factors such as temperature and precipitation. Water demand drivers have been extensively studied, yet they have traditionally been applied to models that assume static conditions and usually do not account for potential societal changes in response to increased scarcity awareness. For example, following a period of sustained low demand such as during a drought, communities often increase water use during a hydrologically wet period, a phenomenon known as "rebounding" water use. Yet previous experiences show the extent of this rebound is not a straightforward function of policy and efficiency improvements, but may also reflect short-term or long-lasting change in community behavior, which are not easily captured by models that assume stationarity. In this study we explore cycles of decreased water demand during drought and subsequent water use rebound observed in California in recent decades. We have developed a novel dynamic system model for water demand in three diverse but interconnected service areas in the San Francisco Bay Area, exposing local trends of changing water use behaviors and long-term impacts on water demand since 1980 to the present. In this model, we apply the concept of social memory, defined as a community's inherited knowledge about hazardous events or degraded environmental conditions from past experiences. While this concept has been applied to further conceptual understanding of socio-hydrologic systems in response to hydrological extremes, to the best of our knowledge this the first study to incorporate social memory to model the water demand rebound phenomenon and to use such a model in the examination of changing dynamics validated by historical data. In addition, we take a closer look at water demand during the recent historic drought in California from 2012-16, and relate our long-term insights to recent events and statewide trends. This comparative modeling exercise shows that increased public awareness during droughts can be related to systematic changes in the way diverse communities respond to near- and long-term conservation incentives.
Horigian, Viviana E; Feaster, Daniel J; Robbins, Michael S; Brincks, Ahnalee M; Ucha, Jessica; Rohrbaugh, Michael J; Shoham, Varda; Bachrach, Ken; Miller, Michael; Burlew, A Kathleen; Hodgkins, Candace C; Carrion, Ibis S; Silverstein, Meredith; Werstlein, Robert; Szapocznik, José
2015-10-01
Young adult drug use and law-breaking behaviors often have roots in adolescence. These behaviors are predicted by early drug use, parental substance use disorders, and disrupted and conflict-ridden family environments. To examine long-term outcomes of Brief Strategic Family Therapy (BSFT) compared to treatment as usual (TAU) in the rates of drug use, number of arrests and externalizing behaviors in young adults who were randomized into treatment conditions as adolescents. 261 of 480 adolescents who had been randomized to BSFT or TAU in the BSFT effectiveness study were assessed at a single time, 3-7 years post randomization. Assessments of drug use, externalizing behaviors, arrests and incarcerations were conducted using Timeline Follow Back, Adult Self Report, and self-report, respectively. Drug use, arrests and incarcerations were examined using negative binomial models and externalizing behaviors were examined using linear regression. When compared with TAU, BSFT youth reported lower incidence of lifetime (IRR = 0.68, 95%CI [0.57, 0.81]) and past year (IRR = 0.54, 95%CI [0.40, 0.71]) arrests; lower rates of lifetime (IRR = 0.63, 95%CI [0.49, 0.81]) and past year (IRR = 0.70, 95%CI [0.53, 0.92]) incarcerations; and lower scores on externalizing behaviors at follow-up (B = -0.42, SE = .15, p = .005). There were no differences in drug use. BSFT may have long term effects in reducing the number of arrests, incarcerations and externalizing problems. These effects could be explained by the improvements in family functioning that occurred during the effectiveness study. This study contributes to the literature by reporting on the long term outcomes of family therapy for adolescent drug abuse. © American Academy of Addiction Psychiatry.
Emergent Constraints for Cloud Feedbacks and Climate Sensitivity
Klein, Stephen A.; Hall, Alex
2015-10-26
Emergent constraints are physically explainable empirical relationships between characteristics of the current climate and long-term climate prediction that emerge in collections of climate model simulations. With the prospect of constraining long-term climate prediction, scientists have recently uncovered several emergent constraints related to long-term cloud feedbacks. We review these proposed emergent constraints, many of which involve the behavior of low-level clouds, and discuss criteria to assess their credibility. With further research, some of the cases we review may eventually become confirmed emergent constraints, provided they are accompanied by credible physical explanations. Because confirmed emergent constraints identify a source of model errormore » that projects onto climate predictions, they deserve extra attention from those developing climate models and climate observations. While a systematic bias cannot be ruled out, it is noteworthy that the promising emergent constraints suggest larger cloud feedback and hence climate sensitivity.« less
Radionuclide Incorporation and Long Term Performance of Apatite Waste Forms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Jianwei; Lian, Jie; Gao, Fei
2016-01-04
This project aims to combines state-of-the-art experimental and characterization techniques with atomistic simulations based on density functional theory (DFT) and molecular dynamics (MD) simulations. With an initial focus on long-lived I-129 and other radionuclides such as Cs, Sr in apatite structure, specific research objectives include the atomic scale understanding of: (1) incorporation behavior of the radionuclides and their effects on the crystal chemistry and phase stability; (2) stability and microstructure evolution of designed waste forms under coupled temperature and radiation environments; (3) incorporation and migration energetics of radionuclides and release behaviors as probed by DFT and molecular dynamics (MD) simulations;more » and (4) chemical durability as measured in dissolution experiments for long term performance evaluation and model validation.« less
Barone Gibbs, Bethany; Kinzel, Laura S; Pettee Gabriel, Kelley; Chang, Yue-Fang; Kuller, Lewis H
2012-09-01
Standard behavioral obesity treatment produces poor long-term results. Focusing on healthy eating behaviors rather than energy intake may be an alternative strategy. In addition, important behaviors might differ for short- vs long-term weight control. Our aim was to describe and compare associations between changes in eating behaviors and weight after 6 and 48 months. We performed secondary analysis of data collected during a randomized weight-loss intervention trial with 48-month follow-up. We studied 481 overweight and obese postmenopausal women enrolled in the Women on the Move through Activity and Nutrition (WOMAN) Study. We measured changes in weight from baseline to 6 and 48 months. Linear regression models were used to examine the associations between 6- and 48-month changes in eating habits assessed by the Conner Diet Habit Survey and changes in weight. Analyses were conducted in the combined study population and stratified by randomization group. At 6 months in the combined population, weight loss was independently associated with decreased desserts (P<0.001), restaurant eating (P=0.042), sugar-sweetened beverages (P=0.009), and fried foods (P<0.001), and increased fish consumption (P=0.003). Results were similar in intervention participants; only reduced desserts and fried foods associated with weight loss in controls. At 48 months in the combined population, weight loss was again associated with decreased desserts (P=0.003) and sugar-sweetened beverages (P=0.011), but also decreased meats/cheeses (P=0.024) and increased fruits/vegetables (P<0.001). Decreased meats/cheeses predicted weight loss in intervention participants; desserts, sugar-sweetened beverages, and fruits/vegetables were independently associated in controls. Changes in eating behaviors were associated with weight change, although important behaviors differed for short- and long-term weight change and by randomization group. Future studies should determine whether interventions targeting these behaviors could improve long-term obesity treatment outcomes. Copyright © 2012 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.
Long-Term Ambient Temperature and Externalizing Behaviors in Adolescents.
Younan, Diana; Li, Lianfa; Tuvblad, Catherine; Wu, Jun; Lurmann, Fred; Franklin, Meredith; Berhane, Kiros; McConnell, Rob; Wu, Anna H; Baker, Laura A; Chen, Jiu-Chiuan
2018-05-21
The climate-violence relationship has been debated for decades, and yet most of the supportive evidence came from ecological or cross-sectional analyses with very limited long-term exposure data. We conducted an individual-level, longitudinal study to investigate the association between ambient temperature and externalizing behaviors of urban-dwelling adolescents. Participants (n = 1,287) of the Risk Factors for Antisocial Behavior Study were examined in 2000-2012 (aged 9-18 years) with repeated assessments of their externalizing behaviors (aggression; delinquency). Ambient temperature data were obtained from the local Meteorological Information System. In adjusted multi-level models, aggressive behaviors significantly increased with rising average temperatures (per 1°C-increment) in preceding 1-3 years (β = 0.23, 95% CI: 0.00, 0.46; β = 0.35, 95% CI: 0.06, 0.63; β = 0.41, 95% CI: 0.08, 0.74; respectively), equivalent to 1.5-3 years of delay in age-related behavioral maturation. These associations were slightly stronger among girls and families of lower socioeconomic status, but greatly diminished in neighborhoods with higher greenspace. No significant associations were found with delinquency. Our study provides the first individual-level epidemiologic evidence supporting the adverse association of long-term ambient temperature and aggression. Similar approaches to studying meteorology and violent crimes may further inform scientific debates on climate change and collective violence.
ERIC Educational Resources Information Center
Kliem, Soren; Kroger, Christoph; Kosfelder, Joachim
2010-01-01
Objective: At present, the most frequently investigated psychosocial intervention for borderline personality disorder (BPD) is dialectical behavior therapy (DBT). We conducted a meta-analysis to examine the efficacy and long-term effectiveness of DBT. Method: Systematic bibliographic research was undertaken to find relevant literature from online…
Exploring Dynamical Assessments of Affect, Behavior, and Cognition and Math State Test Achievement
ERIC Educational Resources Information Center
San Pedro, Maria Ofelia Z.; Snow, Erica L.; Baker, Ryan S.; McNamara, Danielle S.; Heffernan, Neil T.
2015-01-01
There is increasing evidence that fine-grained aspects of student performance and interaction within educational software are predictive of long-term learning. Machine learning models have been used to provide assessments of affect, behavior, and cognition based on analyses of system log data, estimating the probability of a student's particular…
Fractal and chaotic laws on seismic dissipated energy in an energy system of engineering structures
NASA Astrophysics Data System (ADS)
Cui, Yu-Hong; Nie, Yong-An; Yan, Zong-Da; Wu, Guo-You
1998-09-01
Fractal and chaotic laws of engineering structures are discussed in this paper, it means that the intrinsic essences and laws on dynamic systems which are made from seismic dissipated energy intensity E d and intensity of seismic dissipated energy moment I e are analyzed. Based on the intrinsic characters of chaotic and fractal dynamic system of E d and I e, three kinds of approximate dynamic models are rebuilt one by one: index autoregressive model, threshold autoregressive model and local-approximate autoregressive model. The innate laws, essences and systematic error of evolutional behavior I e are explained over all, the short-term behavior predictability and long-term behavior probability of which are analyzed in the end. That may be valuable for earthquake-resistant theory and analysis method in practical engineering structures.
Taylor, H Gerry; Yeates, Keith Owen; Wade, Shari L; Drotar, Dennis; Stancin, Terry; Minich, Nori
2002-01-01
Longitudinal behavior and achievement outcomes of traumatic brain injury (TBI) were investigated in 53 children with severe TBI, 56 children with moderate TBI, and 80 children with orthopedic injuries not involving brain insult. Measures of preinjury child and family status and of postinjury achievement skills were administered shortly after injury. Assessments were repeated 3 times across a mean follow-up interval of 4 years. Results from mixed model analysis revealed persisting sequelae of TBI. Recovery of math skills was observed in the severe TBI group but only for children from less stressed families. Social disadvantage in children with TBI predicted more adverse behavioral sequelae and less favorable changes in some outcome measures. The findings suggest that pediatric TBI has long-term effects on behavior and achievement but that postinjury progress is influenced by the family environment.
Busscher, Bert; Spinhoven, Philip
2017-09-01
To examine the predictive value of cognitive coping strategies at pretreatment and the value of changes in these strategies during cognitive-behavioral treatment for aviophobia for long-term therapy results. Data from baseline, after therapy at 2 months, short-term follow-up at 5 months, and long-term follow-up at 41 months were analyzed (N = 59). Participants were in a long-term process of change, which continued positively after therapy for maladaptive cognitive coping strategies. The use of cognitive coping strategies at baseline was not predictive of long-term outcome. However, a greater increase in the use of adaptive coping strategies, and more importantly, a greater decrease in the use of maladaptive coping strategies were predictive of improvements indicated in self-report of flight anxiety and actual flight behavior at long-term follow-up. Improvement of maladaptive cognitive coping strategies is possibly a key mechanism of change in cognitive-behavioral therapy for aviophobia. © 2016 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Chang, Yao-Feng; Fowler, Burt; Chen, Ying-Chen; Zhou, Fei; Pan, Chih-Hung; Chang, Kuan-Chang; Tsai, Tsung-Ming; Chang, Ting-Chang; Sze, Simon M.; Lee, Jack C.
2016-04-01
We realize a device with biological synaptic behaviors by integrating silicon oxide (SiOx) resistive switching memory with Si diodes to further minimize total synaptic power consumption due to sneak-path currents and demonstrate the capability for spike-induced synaptic behaviors, representing critical milestones for the use of SiO2-based materials in future neuromorphic computing applications. Biological synaptic behaviors such as long-term potentiation, long-term depression, and spike-timing dependent plasticity are demonstrated systemically with comprehensive investigation of spike waveform analyses and represent a potential application for SiOx-based resistive switching materials. The resistive switching SET transition is modeled as hydrogen (proton) release from the (SiH)2 defect to generate the hydrogenbridge defect, and the RESET transition is modeled as an electrochemical reaction (proton capture) that re-forms (SiH)2. The experimental results suggest a simple, robust approach to realize programmable neuromorphic chips compatible with largescale complementary metal-oxide semiconductor manufacturing technology.
NASA Astrophysics Data System (ADS)
Pohl, E.; Maximini, M.; Bauschulte, A.; vom Schloß, J.; Hermanns, R. T. E.
2015-02-01
HT-PEM fuel cells suffer from performance losses due to degradation effects. Therefore, the durability of HT-PEM is currently an important factor of research and development. In this paper a novel approach is presented for an integrated short term and long term simulation of HT-PEM accelerated lifetime testing. The physical phenomena of short term and long term effects are commonly modeled separately due to the different time scales. However, in accelerated lifetime testing, long term degradation effects have a crucial impact on the short term dynamics. Our approach addresses this problem by applying a novel method for dual time scale simulation. A transient system simulation is performed for an open voltage cycle test on a HT-PEM fuel cell for a physical time of 35 days. The analysis describes the system dynamics by numerical electrochemical impedance spectroscopy. Furthermore, a performance assessment is performed in order to demonstrate the efficiency of the approach. The presented approach reduces the simulation time by approximately 73% compared to conventional simulation approach without losing too much accuracy. The approach promises a comprehensive perspective considering short term dynamic behavior and long term degradation effects.
Evolution with Reinforcement Learning in Negotiation
Zou, Yi; Zhan, Wenjie; Shao, Yuan
2014-01-01
Adaptive behavior depends less on the details of the negotiation process and makes more robust predictions in the long term as compared to in the short term. However, the extant literature on population dynamics for behavior adjustment has only examined the current situation. To offset this limitation, we propose a synergy of evolutionary algorithm and reinforcement learning to investigate long-term collective performance and strategy evolution. The model adopts reinforcement learning with a tradeoff between historical and current information to make decisions when the strategies of agents evolve through repeated interactions. The results demonstrate that the strategies in populations converge to stable states, and the agents gradually form steady negotiation habits. Agents that adopt reinforcement learning perform better in payoff, fairness, and stableness than their counterparts using classic evolutionary algorithm. PMID:25048108
Evolution with reinforcement learning in negotiation.
Zou, Yi; Zhan, Wenjie; Shao, Yuan
2014-01-01
Adaptive behavior depends less on the details of the negotiation process and makes more robust predictions in the long term as compared to in the short term. However, the extant literature on population dynamics for behavior adjustment has only examined the current situation. To offset this limitation, we propose a synergy of evolutionary algorithm and reinforcement learning to investigate long-term collective performance and strategy evolution. The model adopts reinforcement learning with a tradeoff between historical and current information to make decisions when the strategies of agents evolve through repeated interactions. The results demonstrate that the strategies in populations converge to stable states, and the agents gradually form steady negotiation habits. Agents that adopt reinforcement learning perform better in payoff, fairness, and stableness than their counterparts using classic evolutionary algorithm.
Revisiting hydraulic hysteresis based on long-term monitoring of hydraulic states in lysimeters
NASA Astrophysics Data System (ADS)
Hannes, M.; Wollschläger, U.; Wöhling, T.; Vogel, H.-J.
2016-05-01
Hysteretic processes have been recognized for decades as an important characteristic of soil hydraulic behavior. Several studies confirmed that wetting and drying periods cannot be described by a simple functional relationship, and that some nonequilibrium of the water retention characteristics has to be taken into account. A large number of models describing the hysteresis of the soil water retention characteristic were successfully tested on soil cores under controlled laboratory conditions. However, its relevance under field conditions under natural forcings has rarely been investigated. In practice, the modeling of field soils usually neglects the hysteretic nature of soil hydraulic properties. In this study, long-term observations of water content and matric potential in lysimeters of the lysimeter network TERENO-SoilCan are presented, clearly demonstrating the hysteretic behavior of field soils. We propose a classification into three categories related to different time scales. Based on synthetic and long-term monitoring data, three different models of hysteresis were applied to data sets showing different degrees of hysteresis. We found no single model to be superior to the others. The model ranking depended on the degree of hysteresis. All models were able to reflect the general structure of hysteresis in most cases but failed to reproduce the detailed trajectories of state variables especially under highly transient conditions. As an important result we found that the temporal dynamics of wetting and drying significantly affects these trajectories which should be accounted for in future model concepts.
Golay, Alain
2006-01-01
A diet always induces weight loss in the short term. The loss does not depend on the dietary composition but rather on the caloric deficit. However, a drastic diet often induces binge eating disorders and can lead to a weight gain in the long term. A cognitive-behavioral-nutritional approach allows lasting weight loss and best results with low fat diets in the long term. Therapeutic education is a patient-centered humanistic approach which allows patients to be actors in their own treatment and own diet to improve their success in losing weight and their quality of life. Motivational interviewing and cognitive-behavioral approaches are perfect complements to therapeutic education for long-term weight loss maintenance. Finally, the best diet is the one that the patient can follow in the long term.
Short-term and long-term effects of violent media on aggression in children and adults.
Bushman, Brad J; Huesmann, L Rowell
2006-04-01
To test whether the results of the accumulated studies on media violence and aggressive behavior are consistent with the theories that have evolved to explain the effects. We tested for the existence of both short-term and long-term effects for aggressive behavior. We also tested the theory-driven hypothesis that short-term effects should be greater for adults and long-term effects should be greater for children. Meta-analysis. Children younger than 18 years and adults. Violent media, including TV, movies, video games, music, and comic books. Measures of aggressive behavior, aggressive thoughts, angry feelings, physiological arousal (eg, heart rate, blood pressure), and helping behavior. Effect size estimates were combined using meta-analytic procedures. As expected, the short-term effects of violent media were greater for adults than for children whereas the long-term effects were greater for children than for adults. The results also showed that there were overall modest but significant effect sizes for exposure to media violence on aggressive behaviors, aggressive thoughts, angry feelings, arousal levels, and helping behavior. The results are consistent with the theory that short-term effects are mostly due to the priming of existing well-encoded scripts, schemas, or beliefs, which adults have had more time to encode. In contrast, long-term effects require the learning (encoding) of scripts, schemas, or beliefs. Children can encode new scripts, schemas, and beliefs via observational learning with less interference and effort than adults.
Takano, Sotaro; Pawlowska, Bogna J; Gudelj, Ivana; Yomo, Tetsuya; Tsuru, Saburo
2017-02-07
The amount of natural resources in the Earth's environment is in flux, which can trigger catastrophic collapses of ecosystems. How populations survive under nutrient-poor conditions is a central question in ecology. Curiously, some bacteria persist for a long time in nutrient-poor environments. Although this survival may be accomplished through cell death and the recycling of dead cells, the importance of these processes and the mechanisms underlying the survival of the populations have not been quantitated. Here, we use microbial laboratory experiments and mathematical models to demonstrate that death and recycling are essential activities for the maintenance of cell survival. We also show that the behavior of the survivors is governed by population density feedback, wherein growth is limited not only by the available resources but also by the population density. The numerical simulations suggest that population density-dependent recycling could be an advantageous behavior under starvation conditions. How organisms survive after exhaustion of resources is a central question in ecology. Starving Escherichia coli constitute a model system to understand survival mechanisms during long-term starvation. Although death and the recycling of dead cells might play a key role in the maintenance of long-term survival, their mechanisms and importance have not been quantitated. Here, we verified the significance of social recycling of dead cells for long-term survival. We also show that the survivors restrained their recycling and did not use all available nutrients released from dead cells, which may be advantageous under starvation conditions. These results indicate that not only the utilization of dead cells but also restrained recycling coordinate the effective utilization of limited resources for long-term survival under starvation. Copyright © 2017 Takano et al.
Creep-rupture reliability analysis
NASA Technical Reports Server (NTRS)
Peralta-Duran, A.; Wirsching, P. H.
1984-01-01
A probabilistic approach to the correlation and extrapolation of creep-rupture data is presented. Time temperature parameters (TTP) are used to correlate the data, and an analytical expression for the master curve is developed. The expression provides a simple model for the statistical distribution of strength and fits neatly into a probabilistic design format. The analysis focuses on the Larson-Miller and on the Manson-Haferd parameters, but it can be applied to any of the TTP's. A method is developed for evaluating material dependent constants for TTP's. It is shown that optimized constants can provide a significant improvement in the correlation of the data, thereby reducing modelling error. Attempts were made to quantify the performance of the proposed method in predicting long term behavior. Uncertainty in predicting long term behavior from short term tests was derived for several sets of data. Examples are presented which illustrate the theory and demonstrate the application of state of the art reliability methods to the design of components under creep.
Chi, Cynthia A; Clark, Damon A; Lee, Stella; Biron, David; Luo, Linjiao; Gabel, Christopher V; Brown, Jeffrey; Sengupta, Piali; Samuel, Aravinthan D T
2007-11-01
Thermotactic behavior in the nematode Caenorhabditis elegans exhibits long-term plasticity. On a spatial thermal gradient, C. elegans tracks isotherms near a remembered set-point (T(S)) corresponding to its previous cultivation temperature. When navigating at temperatures above its set-point (T>T(S)), C. elegans crawls down spatial thermal gradients towards the T(S) in what is called cryophilic movement. The T(S) retains plasticity in the adult stage and is reset by approximately 4 h of sustained exposure to a new temperature. Long-term plasticity in C. elegans thermotactic behavior has been proposed to represent an associative learning of specific temperatures conditioned in the presence or absence of bacterial food. Here, we use quantitative behavioral assays to define the temperature and food-dependent determinants of long-term plasticity in the different modes of thermotactic behavior. Under our experimental conditions, we find that starvation at a specific temperature neither disrupts T(S) resetting toward the starvation temperature nor induces learned avoidance of the starvation temperature. We find that prolonged starvation suppresses the cryophilic mode of thermotactic behavior. The hen-1 and tax-6 genes have been reported to affect associative learning between temperature and food-dependent cues. Under our experimental conditions, mutation in the hen-1 gene, which encodes a secreted protein with an LDL receptor motif, does not significantly affect thermotactic behavior or long-term plasticity. Mutation in the tax-6 calcineurin gene abolishes thermotactic behavior altogether. In summary, we do not find evidence that long-term plasticity requires association between temperature and the presence or absence of bacterial food.
The behavior of renal-regulating hormones during hypogravic stress
NASA Technical Reports Server (NTRS)
Leonard, J. I.
1985-01-01
The regulation of fluid and electrolyte behavior during space flight is believed to be under control, in large part, of a group of hormones which have their major effects on renal excretion. The hormones studied include renin-angitensin, aldosterone, and antidiuretic hormone (ADH). The regulatory systems of these renal-regulating hormones as they act individually and in concert with each other are analyzed. The analysis is based on simulations of the mathematical model of Guyton. A generalized theory is described which accounts for both short-term and long-term behavior of this set of hormones.
Eastwick, Paul W; Keneski, Elizabeth; Morgan, Taylor A; McDonald, Meagan A; Huang, Sabrina A
2018-05-01
Close relationships research has examined committed couples (e.g., dating relationships, marriages) using intensive methods that plot relationship development over time. But a substantial proportion of people's real-life sexual experiences take place (a) before committed relationships become "official" and (b) in short-term relationships; methods that document the time course of relationships have rarely been applied to these contexts. We adapted a classic relationship trajectory-plotting technique to generate the first empirical comparisons between the features of people's real-life short-term and long-term relationships across their entire timespan. Five studies compared long-term and short-term relationships in terms of the timing of relationship milestones (e.g., flirting, first sexual intercourse) and the occurrence/intensity of important relationship experiences (e.g., romantic interest, strong sexual desire, attachment). As romantic interest was rising and partners were becoming acquainted, long-term and short-term relationships were indistinguishable. Eventually, romantic interest in short-term relationships plateaued and declined while romantic interest in long-term relationships continued to rise, ultimately reaching a higher peak. As relationships progressed, participants evidenced more features characteristic of the attachment-behavioral system (e.g., attachment, caregiving) in long-term than short-term relationships but similar levels of other features (e.g., sexual desire, self-promotion, intrasexual competition). These data inform a new synthesis of close relationships and evolutionary psychological perspectives called the Relationship Coordination and Strategic Timing (ReCAST) model. ReCAST depicts short-term and long-term relationships as partially overlapping trajectories (rather than relationships initiated with distinct strategies) that differ in their progression along a normative relationship development sequence. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Sun exposure and protection behaviors among long-term melanoma survivors and non-cancer controls
Vogel, Rachel Isaksson; Strayer, Lori G.; Engelman, Leah; Nelson, Heather H.; Blaes, Anne H.; Anderson, Kristin E.; Lazovich, DeAnn
2016-01-01
Introduction Melanoma is considered a generally preventable cancer, with excessive ultraviolet radiation (UVR) exposure being a strong causal factor. UVR exposure following a melanoma diagnosis can be modified to reduce risk of second primary melanomas. The goal of this study was to compare measures of UVR exposure and protection behaviors between long-term melanoma survivors and controls. Methods Participants from a previously conducted case-control study were recruited for a cross-sectional survey. Melanoma cases were 25–59 years old at diagnosis; controls were age and sex matched. Participants were asked about UVR exposure and protection measures used in the past year and comparisons between melanoma survivors and controls were conducted using logistic regression models, adjusting for potential confounders. Results A total of 726 (67.7%) long-term melanoma survivors and 657 (60.9%) controls completed the follow-up survey. Melanoma survivors were significantly less likely to report high sun exposure on a typical weekday (OR=0.72 [0.55–0.94]), sunburns (OR=0.40 [0.30–0.53]), or indoor tanning (OR=0.20 [0.09–0.44]) than controls; however high sun exposure on a typical weekend day was similar. Report of optimal sun protection behaviors were higher in melanoma survivors compared to controls. However, a few melanoma survivors reported indoor tanning, 10% reported intentionally seeking sun to tan, and 20% reported sunburns. Conclusion Although long term melanoma survivors reported healthier UVR exposure and protection behaviors compared to controls, a sizeable proportion still reported elevated sun exposure, sunburns, and suboptimal UVR protection behaviors. Impact Opportunities remain for improving sun protection to reduce future melanoma risk among melanoma survivors. PMID:28254810
Robust retention and transfer of tool construction techniques in chimpanzees (Pan troglodytes).
Vale, Gill L; Flynn, Emma G; Pender, Lydia; Price, Elizabeth; Whiten, Andrew; Lambeth, Susan P; Schapiro, Steven J; Kendal, Rachel L
2016-02-01
Long-term memory can be critical to a species' survival in environments with seasonal and even longer-term cycles of resource availability. The present, longitudinal study investigated whether complex tool behaviors used to gain an out-of-reach reward, following a hiatus of about 3 years and 7 months since initial experiences with a tool use task, were retained and subsequently executed more quickly by experienced than by naïve chimpanzees. Ten of the 11 retested chimpanzees displayed impressive long-term procedural memory, creating elongated tools using the same methods employed years previously, either combining 2 tools or extending a single tool. The complex tool behaviors were also transferred to a different task context, showing behavioral flexibility. This represents some of the first evidence for appreciable long-term procedural memory, and improvements in the utility of complex tool manufacture in chimpanzees. Such long-term procedural memory and behavioral flexibility have important implications for the longevity and transmission of behavioral traditions. (c) 2016 APA, all rights reserved).
Robust Retention and Transfer of Tool Construction Techniques in Chimpanzees (Pan troglodytes)
Vale, Gill L.; Flynn, Emma G.; Pender, Lydia; Price, Elizabeth; Whiten, Andrew; Lambeth, Susan P.; Schapiro, Steven J.; Kendal, Rachel L.
2016-01-01
Long-term memory can be critical to a species’ survival in environments with seasonal and even longer-term cycles of resource availability. The present, longitudinal study investigated whether complex tool behaviors used to gain an out-of-reach reward, following a hiatus of about 3 years and 7 months since initial experiences with a tool use task, were retained and subsequently executed more quickly by experienced than by naïve chimpanzees. Ten of the 11 retested chimpanzees displayed impressive long-term procedural memory, creating elongated tools using the same methods employed years previously, either combining 2 tools or extending a single tool. The complex tool behaviors were also transferred to a different task context, showing behavioral flexibility. This represents some of the first evidence for appreciable long-term procedural memory, and improvements in the utility of complex tool manufacture in chimpanzees. Such long-term procedural memory and behavioral flexibility have important implications for the longevity and transmission of behavioral traditions. PMID:26881941
Seehafer, Kia; Brophy, Samantha; Tom, Sara R.; Crook, Robyn J.
2018-01-01
Cephalopod molluscs are known for their extensive behavioral repertoire and their impressive learning abilities. Their primary defensive behaviors, such as camouflage, have received detailed study, but knowledge is limited to intensive study of relatively few species. A considerable challenge facing cephalopod research is the need to establish new models that can be captive bred, are tractable for range of different experimental procedures, and that will address broad questions in biological research. The Hawaiian Bobtail Squid (Euprymna scolopes) is a small, tropical cephalopod that has a long history of research in the field of microbial symbiosis, but offers great promise as a novel behavioral and neurobiological model. It can be bred in the laboratory through multiple generations, one of the few species of cephalopod that can meet this requirement (which is incorporated in regulations such as EU directive 2010/63/EU). Additionally, laboratory culture makes E. scolopes an ideal model for studying ontogeny- and experience-dependent behaviors. In this study, we show that captive bred juvenile and adult E. scolopes produce robust, repeatable defensive behaviors when placed in an exposed environment and presented with a visual threat. Further, adult and juvenile squid employ different innate defensive behaviors when presented with a size-matched model predator. When a 10-min training procedure was repeated over three consecutive days, defensive behaviors habituated in juvenile squid for at least 5 days after training, but memory did not appear to persist for 14 days. In contrast, adult squid did not show any evidence of long-term habituation memory. Thus we conclude that this species produces a range of quantifiable, modifiable behaviors even in a laboratory environment where ecologically-relevant, complex behavioral sequences may not reliably occur. We suggest that the lack of long-term memory in adult squid may be related to their less escalated initial response to the mimic, and thus indicates less motivation to retain memory and not necessary inability to form memory. This is the first demonstration of age-related differences in defensive behaviors in Euprymna, and the first record of habituation in this experimentally tractable genus of squid. PMID:29651249
Barlińska, Julia; Szuster, Anna; Winiewski, Mikołaj
2015-04-01
The long- versus short-term effectiveness of empathy activation on reducing bystander behavior reinforcing cyberbullying was tested. The focus was on limiting the frequency of forwarding a message ridiculing a peer. Experimental research on adolescent students was conducted in conditions simulating online contact. The results confirmed the significance of cognitive empathy activated immediately prior to decision making on limiting involvement in reinforcing cyberbullying behavior. The long-term impact of empathy was markedly limited.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neu, Richard W.
The aim of this project is to develop a microstructure-sensitive crystal viscoplasticity (CVP) model for single-crystal Ni-base superalloys to model the behavior of the material and components in the hot gas path sections of industrial gas turbines (IGT). Microstructure degradation associated with aging critical to predicting long-term creep-fatigue interactions will be embedded into the model through the γ' precipitate morphology evolution by coupling the coarsening drivers and kinetics into the constitutive equations of the CVP model. Model parameters will be determined using new experimental protocols that involve systematically artificially aging the alloy under different stress conditions to determine the relationshipmore » between the size and morphology g' precipitates on the creep and thermomechanical fatigue response.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neu, Richard W
The aim of this project is to develop a microstructure-sensitive crystal viscoplasticity (CVP) model for single-crystal Ni-base superalloys to model the behavior of the material and components in the hot gas path sections of industrial gas turbines (IGT). Microstructure degradation associated with aging critical to predicting long-term creep-fatigue interactions will be embedded into the model through the γ' precipitate morphology evolution by coupling the coarsening drivers and kinetics into the constitutive equations of the CVP model. Model parameters will be determined using new experimental protocols that involve systematically artificially aging the alloy under different stress conditions to determine the relationshipmore » between the size and morphology g' precipitates on the creep and thermomechanical fatigue response.« less
NASA Technical Reports Server (NTRS)
Waldman, H.
1971-01-01
The long-term variations in the daytime exchange flux are estimated with the use of model hydrogen concentrations based on the inverse relationship between the abundance of neutral hydrogen and the neutral temperature in the thermosphere. The results are found to be compatible with the observed long-term behavior of the ionospheric electron content at a midlatitude location, as revealed by Faraday observations using geostationary satellites. The basic processes occurring in the ionosphere are reviewed, with emphasis on the concepts of limiting velocity and limiting flux. An approach to the problem of numerical simulation of the ionosphere is also presented and discussed.
On the long term evolution of white dwarfs in cataclysmic variables and their recurrence times
NASA Technical Reports Server (NTRS)
Sion, E. M.; Starrfield, S. G.
1985-01-01
The relevance of the long term quasi-static evolution of accreting white dwarfs to the outbursts of Z Andromeda-like symbiotics; the masses and accretion rates of classical nova white dwarfs; and the observed properties of white dwarfs detected optically and with IUE in low M dot cataclysmic variables is discussed. A surface luminosity versus time plot for a massive, hot white dwarf bears a remarkable similarity to the outburst behavior of the hot blue source in Z Andromeda. The long term quasi-static models of hot accreting white dwarfs provide convenient constraints on the theoretically permissible parameters to give a dynamical (nova-like) outburst of classic white dwarfs.
Market Efficiency and the Risks and Returns of Dynamic Trading Strategies with Commodity Futures
NASA Astrophysics Data System (ADS)
Switzer, Lorne N.; Jiang, Hui
This paper investigates relationships between profits from dynamic trading strategies, risk premium, convenience yields, and net hedging pressures for commodity futures. As a market efficiency study, it crosses a number of disciplines, including traditional finance, behavioral finance, and behavioral psychology. The term structure of oil, gold, copper and soybeans futures markets contains predictive power for the corresponding term premium. However, only oil futures and soybean futures lead their spot premium. Significant momentum profits are identified in both outright futures and spread trading strategies when the spot premium and the term premium are used to form winner and loser portfolios. Profits from active strategies based on winner and loser portfolios are conditioned on market structure and net hedging pressure effects. Dynamic trading strategies based on contracts with extreme backwardation, extreme contango, and extreme hedging pressures are also tested. On average, spread trading outperforms outright futures trading in capturing the term structure risk and hedging pressure risk. For such strategies, long-short the long-term spread offers the greatest and most significant return and it offers the only exploitable trading profits built on the past hedging pressure. The existence of profits from active trading strategies based on winners is consistent with behavioral finance and behavioral psychology models in which market participants irrationally overreact to information and trends.
Characterizing Periodic Messaging Interventions Across Health Behaviors and Media: Systematic Review
Fuentes, Laura W; Cohen, Joanna E
2014-01-01
Background Periodic prompts serve as tools for health behavior interventions to encourage and maintain behavior changes. Past literature reviews have examined periodic messages targeting specific behaviors (smoking, physical activity, diet, etc) or media (telephone, email, face-to-face, newsletter, etc) and have found them to be effective in impacting health behavior in the short term. Objective Our goal was to review the literature related to periodic messaging and prompts in order to explore typical characteristics, assess the role of prompt timing, identify common theoretical models used, and identify characteristics associated with the effectiveness of periodic prompts. Methods Electronic searches of PubMed, PsycINFO, CINAHL, and Web of Science were conducted in October 2012 and May 2013. Database search terms included variant terms for periods, prompts, interventions, media, and health behaviors. Results Forty-two of the 55 included research articles found that prompts resulted in significant positive behavioral outcomes for participants. Prompts were delivered via text messages, email, mailed communications, and in a few instances via phone. Generally, the provision of feedback and specific strategies to accomplish behavior change appears to be important for the success of periodic prompts. Rationale for prompt timing was rarely provided, although some studies did organize message content around days of the week or times perceived to be high risk for particular behaviors. Smoking cessation interventions tended to be organized around quit date. Among studies using theoretical models to inform their interventions, the transtheoretical model was most common. Conclusions Periodic messaging interventions yield positive results for short-term health behavior changes. Interventions including feedback and prompts that included strategies were more likely to report significantly positive outcomes. Work remains to better understand elements that make periodic prompts successful and whether they are effective in producing long-term outcomes. PMID:24667840
Zhao, Lei; Wong, Adrian; Luo, Yishan; Liu, Wenyan; Chu, Winnie W C; Abrigo, Jill M; Lee, Ryan K L; Mok, Vincent; Shi, Lin
2018-01-01
White matter hyperintensities (WMH) are common in acute ischemic stroke patients. Although WMH volume has been reported to influence post-stroke cognition, it is still not clear whether WMH location, independent of acute ischemic lesion (AIL) volume and location, contributes to cognitive impairment after stroke. Here, we proposed a multiple-lesion symptom mapping model that considers both the presence of WMH and AIL to measure the additional contribution of WMH locations to post-stroke cognitive impairment. Seventy-six first-ever stroke patients with AILs in the left hemisphere were examined by Montreal Cognitive Assessment (MoCA) at baseline and 1 year after stroke. The association between the location of AIL and WMH and global cognition was investigated by a multiple-lesion symptom mapping (MLSM) model based on support vector regression (SVR). To explore the relative merits of MLSM over the existing lesion-symptom mapping approaches with only AIL considered (mass-univariate VLSM and SVR-LSM), we measured the contribution of the significant AIL and/or WMH clusters from these models to post-stroke cognitive impairment. In addition, we compared the significant WMH locations identified by the optimal SVR-MLSM model for cognitive impairment at baseline and 1 year post stroke. The identified strategic locations of WMH significantly contributed to the prediction of MoCA at baseline (short-term) and 1 year (long-term) after stroke independent of the strategic locations of AIL. The significant clusters of WMH for short-term and long-term post-stroke cognitive impairment were mainly in the corpus callosum, corona radiata, and posterior thalamic radiation. We noted that in some regions, the AIL clusters that were significant for short-term outcome were no longer significant for long-term outcome, and interestingly more WMH clusters in these regions became significant for long-term outcome compared to short-term outcome. This indicated that there are some regions where local WMH burden has larger impact than AIL burden on the long-term post-stroke cognitive impairment. In consequence, SVR-MLSM was effective in identifying the WMH locations that have additional impact on post-stroke cognition on top of AIL locations. Such a method can also be applied to other lesion-behavior studies where multiple types of lesions may have potential contributions to a specific behavior.
Suicidal Behavior in Long-Term Care Facilities.
ERIC Educational Resources Information Center
Osgood, Nancy J.; Brant, Barbara A.
1990-01-01
Surveyed administrators of 463 long-term care facilities concerning overt suicides and intentional life-threatening behaviors. Data revealed that White males were highest risk group. Refusal to eat, drink, or take medications were most common suicidal behaviors. Depression, loneliness, feelings of family rejection, and loss were significant…
ERIC Educational Resources Information Center
Jones, Sherry Everett; Lollar, Donald J.
2008-01-01
Background: This study explores the relationship between self-reported physical disabilities or long-term health problems and health risk behaviors or adverse health conditions (self-reported engagement in violent behaviors, attempted suicide, cigarette smoking, alcohol and other drug use, sexual activity, physical activity, dietary behaviors,…
Long-lasting Effects of Minocycline on Behavior in Young but not Adult Fragile X Mice
Dansie, Lorraine E.; Phommahaxay, Kelly; Okusanya, Ayodeji G.; Uwadia, Jessica; Huang, Mike; Rotschafer, Sarah E.; Razak, Khaleel A.; Ethell, Douglas W.; Ethell, Iryna M.
2013-01-01
Fragile X Syndrome (FXS) is the most common single-gene inherited form of intellectual disability with behaviors characteristic of autism. People with FXS display childhood seizures, hyperactivity, anxiety, developmental delay, attention deficits, and visual-spatial memory impairment, as well as a propensity for obsessive-compulsive disorder (OCD). Several of these aberrant behaviors and FXS-associated synaptic irregularities also occur in “fragile X mental retardation gene” knock-out (Fmr1 KO) mice. We previously reported that minocycline promotes the maturation of dendritic spines - postsynaptic sites for excitatory synapses - in the developing hippocampus of Fmr1 KO mice, which may underlie the beneficial effects of minocycline on anxiolytic behavior in young Fmr1 KO mice. In this study, we compared the effectiveness of minocycline treatment in young and adult Fmr1 KO mice, and determined the dependence of behavioral improvements on short-term versus long-term minocycline administration. We found that 4 and 8 week long treatments significantly reduced locomotor activity in both young and adult Fmr1 KO mice. Some behavioral improvements persisted in young mice post-treatment, but in adults the beneficial effects were lost soon after minocycline treatment was stopped. We also show, for the first time, that minocycline treatment partially attenuates the number and severity of audiogenic seizures in Fmr1 KO mice. This report provides further evidence that minocycline treatment has immediate and long-lasting benefits on FXS-associated behaviors in the Fmr1 KO mouse model. PMID:23660195
Chaby, Lauren E; Cavigelli, Sonia A; White, Amanda; Wang, Kayllie; Braithwaite, Victoria A
2013-01-01
Animals that experience adverse events in early life often have life-long changes to their physiology and behavior. Long-term effects of stress during early life have been studied extensively, but less attention has been given to the consequences of negative experiences solely during the adolescent phase. Adolescence is a particularly sensitive period of life when regulation of the glucocorticoid "stress" hormone response matures and specific regions in the brain undergo considerable change. Aversive experiences during this time might, therefore, be expected to generate long-term consequences for the adult phenotype. Here we investigated the long-term effects of exposure to chronic unpredictable stress during adolescence on adult decision-making, coping response, cognitive bias, and exploratory behavior in rats. Rats exposed to chronic unpredictable stress (e.g., isolation, crowding, cage tilt) were compared to control animals that were maintained in standard, predictable conditions throughout development. Unpredictable stress during adolescence resulted in a suite of long-term behavioral and cognitive changes including a negative cognitive bias [F (1, 12) = 5.000, P < 0.05], altered coping response [T (1, 14) = 2.216, P = 0.04], and accelerated decision-making [T (1, 14) = 3.245, P = 0.01]. Exposure to chronic stress during adolescence also caused a short-term increase in boldness behaviors; in a novel object test 15 days after the last stressor, animals exposed to chronic unpredictable stress had decreased latencies to leave a familiar shelter and approach a novel object [T (1, 14) = 2.240, P = 0.04; T (1, 14) = 2.419, P = 0.03, respectively]. The results showed that stress during adolescence has long-term impacts on behavior and cognition that affect the interpretation of ambiguous stimuli, behavioral response to adverse events, and how animals make decisions.
Belda, Xavier; Márquez, Cristina; Armario, Antonio
2004-10-05
We have previously observed that a single exposure to immobilization (IMO), a severe stressor, caused long-term (days to weeks) desensitization of the response of the hypothalamic-pituitary-adrenal (HPA) axis to the homotypic stressor, with no changes in behavioral reactivity to novel environments. In contrast, other laboratories have reported that a single exposure to footshock induced a long-term sensitization of both HPA and behavioral responses to novel environments. To test whether these apparent discrepancies can be explained by the use of different stressors or different strains of rats, we studied in the present work the long-term effects of a single exposure to two different stressors (footshock or IMO) in two different strains of rats (Sprague-Dawley from Iffa-Credo and Wistar rats from Harlan). We found that both strains showed desensitization of the HPA response to the same (homotypic) stressor after a previous exposure to either shock or IMO. The long-term effects were higher after IMO than shock. No major changes in behavior in two novel environments (circular corridor, CC and elevated plus-maze, EPM) were observed after a single exposure to shock or IMO in neither strain, despite the fact that shocked rats showed a conditioned freezing response to the shock boxes. The present results demonstrate that long-term stress-induced desensitization of the HPA axis is a reliable phenomenon that can be observed with different stressors and strains. However, only behavioral changes related to shock-induced conditioned fear were found, which suggests that so far poorly characterized factors are determining the long-term behavioral consequences of a single exposure to stress.
Chen, Kuang-Ti; Wu, Ching-Hsiang; Tsai, Mang-Hung; Wu, Ya-Chieh; Jou, Ming-Jia; Huang, Chih-Chia; Wei, I-Hua
2017-01-01
Sarcosine, an N-methyl-d-aspartate receptor enhancer, can improve depression-like behavior in rodent models and depression in humans. We found that a single dose of sarcosine exerted antidepressant-like effects with rapid concomitant increases in the mammalian target of rapamycin (mTOR) signaling pathway activation and enhancement of α-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor (AMPAR) membrane insertion. Sarcosine may play a crucial role in developing novel therapy for depression. For a detailed understanding of sarcosine, this study examined the effects of long-term sarcosine treatment on the forced swim test (FST), mTOR signaling, and AMPAR membrane insertion in rats. The effects of long-term sarcosine treatment were examined in naive rats and rats exposed to chronic unpredictable stress (CUS). Long-term sarcosine treatment (560mg/kg/d for 21 d) significantly ameliorated the increased immobility induced by CUS in the FST, reaffirming the potential role of sarcosine as an antidepressant for depressed patients. The same long-term treatment exhibited no such effect in naive rats despite increased mTOR activation and AMPAR membrane insertion in both groups. Our findings clearly show CUS-exposed rats are sensitive to long-term sarcosine treatment in FST and the response at the same dose is absent in naïve rats. Nevertheless, the distinct sensitivity to long-term sarcosine treatment in rats with or without CUS is not associated with the activated mTOR signaling pathway or increased AMPAR membrane insertion. Additionally, understanding the behavioral and molecular basis of distinct responses is vital important for developing personalized treatment programs to increase the probability of success when treating depression. Copyright © 2016. Published by Elsevier B.V.
Belda, Xavier; Fuentes, Silvia; Nadal, Roser; Armario, Antonio
2008-11-01
We have previously reported that a single exposure to immobilization (IMO) in rats causes a long-term desensitization of the hypothalamic-pituitary-adrenal (HPA) response to the same (homotypic) stressor. Since there are reports showing that a single exposure to other stressors causes sensitization of the HPA response to heterotypic stressors and increases anxiety-like behavior, we studied in the present work the long-term effects of IMO on behavioral and HPA response to mild superimposed stressors. In Experiments 1 and 2, adult male Sprague-Dawley rats were subjected to 2 h of IMO and then exposed for 5 min to the elevated plus-maze (EPM) at 1, 3 or 7 days after IMO. Blood samples were taken at 15 min after initial exposure to the EPM. Increases in anxiety-like behavior and HPA responsiveness to the EPM were found at all times post-IMO. Changes in the resting levels of HPA hormones did not explain the enhanced HPA responsiveness to the EPM (Experiment 3). In Experiments 4 and 5, we studied the effects of a single exposure to a shorter session of IMO (1 h) on behavioral and HPA responses to a brief and mild session of foot-shocks done 10 days after IMO. Neither previous IMO nor exposure to shocks in control rats modified behavior in the EPM. However, a brief session of shocks in previously IMO-exposed rats dramatically increased anxiety in the EPM. HPA and freezing responses to shocks were similar in control and previous IMO groups. Therefore, a single exposure to IMO appears to induce long-lasting HPA and behavioral sensitization to mild superimposed stressors, although the two responses are likely to be at least partially independent. Long-term effects of IMO on the susceptibility to stress-induced endocrine and emotional disturbances may be relevant to the characterization of animal models of post-traumatic stress.
NASA Astrophysics Data System (ADS)
Bhattacharya, Utso; Dutta, Amit
2018-06-01
We study the one-dimensional Kitaev chain with long-range superconductive pairing terms at a finite temperature where the system is prepared in a mixed state in equilibrium with a heat reservoir maintained at a constant temperature T . In order to probe the footprint of the ground-state topological behavior of the model at finite temperature, we look at two global quantities extracted out of two geometrical constructions: the Uhlmann and the interferometric phase. Interestingly, when the long-range effect dominates, the Uhlmann phase approach fails to reproduce the topological aspects of the model in the pure-state limit; on the other hand, the interferometric phase which has a proper pure state reduction, shows a behavior independent of the ambient temperature.
NASA Astrophysics Data System (ADS)
Lokoshchenko, A. M.
2014-01-01
Basic results of experimental and theoretical research of creep processes and long-term strength of metals obtained by researchers of the Institute of Mechanics at the Lomonosov Moscow State University are presented. These results further develop and refine the kinetic theory of creep and long-duration strength proposed by Yu. N. Rabotnov. Some problems arising in formulating various types of kinetic equations and describing experimental data for materials that can be considered as statically homogeneous materials (in studying the process of deformation and rupture of such materials, there is no need to study the evolution of individual cracks) are considered. The main specific features of metal creep models at constant and variable stresses, in uniaxial and complex stress states, and with allowance for one or two damage parameters are described. Criterial and kinetic approaches used to determine long-term strength under conditions of a complex stress state are considered. Methods of modeling the metal behavior in an aggressive medium are described. A possibility of using these models for solving engineering problems is demonstrated.
42 CFR 483.13 - Resident behavior and facility practices.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 5 2010-10-01 2010-10-01 false Resident behavior and facility practices. 483.13... SERVICES (CONTINUED) STANDARDS AND CERTIFICATION REQUIREMENTS FOR STATES AND LONG TERM CARE FACILITIES Requirements for Long Term Care Facilities § 483.13 Resident behavior and facility practices. (a) Restraints...
Stenberg, Nicola; Furness, Penny J
2017-03-01
The outcomes of self-management interventions are commonly assessed using quantitative measurement tools, and few studies ask people with long-term conditions to explain, in their own words, what aspects of the intervention they valued. In this Grounded Theory study, a Health Trainers service in the north of England was evaluated based on interviews with eight service-users. Open, focused, and theoretical coding led to the development of a preliminary model explaining participants' experiences and perceived impact of the service. The model reflects the findings that living well with a long-term condition encompassed social connectedness, changed identities, acceptance, and self-care. Health trainers performed four related roles that were perceived to contribute to these outcomes: conceptualizer, connector, coach, and champion. The evaluation contributes a grounded theoretical understanding of a personalized self-management intervention that emphasizes the benefits of a holistic approach to enable cognitive, behavioral, emotional, and social adjustments.
Takeuchi, Koichi; Gertner, Michael J; Zhou, Jing; Parada, Luis F; Bennett, Michael V L; Zukin, R Suzanne
2013-03-19
The phosphoinositide signaling system is a crucial regulator of neural development, cell survival, and plasticity. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) negatively regulates phosphatidylinositol 3-kinase signaling and downstream targets. Nse-Cre Pten conditional knockout mice, in which Pten is ablated in granule cells of the dentate gyrus and pyramidal neurons of the hippocampal CA3, but not CA1, recapitulate many of the symptoms of humans with inactivating PTEN mutations, including progressive hypertrophy of the dentate gyrus and deficits in hippocampus-based social and cognitive behaviors. However, the impact of Pten loss on activity-dependent synaptic plasticity in this clinically relevant mouse model of Pten inactivation remains unclear. Here, we show that two phosphatidylinositol 3-kinase- and protein synthesis-dependent forms of synaptic plasticity, theta burst-induced long-term potentiation and metabotropic glutamate receptor (mGluR)-dependent long-term depression, are dysregulated at medial perforant path-to-dentate gyrus synapses of young Nse-Cre Pten conditional knockout mice before the onset of visible morphological abnormalities. In contrast, long-term potentiation and mGluR-dependent long-term depression are normal at CA3-CA1 pyramidal cell synapses at this age. Our results reveal that deletion of Pten in dentate granule cells dysregulates synaptic plasticity, a defect that may underlie abnormal social and cognitive behaviors observed in humans with Pten inactivating mutations and potentially other autism spectrum disorders.
Funding long-term care: applications of the trade-off principle in both public and private sectors.
Chen, Yung-Ping
2003-02-01
The uncertain need for long-term care services is a risk best protected by insurance. However, the current funding relies heavily on personal payment and public welfare, and only lightly on social and private insurances. This method, akin to sitting on a two-legged stool, is unlikely to be sustainable. To incorporate insurance as a key component of funding and to mobilize public and private resources more effectively, we propose a three-legged-stool funding model under which social insurance would provide a basic protection, to be supplemented by private insurance and personal payment. When these sources do not provide sufficient protection for some individuals, Medicaid as public welfare would serve as a safety net. This article (a) discusses how to implement this funding model by using the trade-off principle in both the public and private sectors when resources for long-term care are scarce, and (b) analyzes several objections to this model from cognitive psychology/behavioral economics
View-Based Organization and Interplay of Spatial Working and Long-Term Memories
Röhrich, Wolfgang G.; Hardiess, Gregor; Mallot, Hanspeter A.
2014-01-01
Space perception provides egocentric, oriented views of the environment from which working and long-term memories are constructed. “Allocentric” (i.e. position-independent) long-term memories may be organized as graphs of recognized places or views but the interaction of such cognitive graphs with egocentric working memories is unclear. Here we present a simple coherent model of view-based working and long-term memories, together with supporting evidence from behavioral experiments. The model predicts that within a given place, memories for some views may be more salient than others, that imagery of a target square should depend on the location where the recall takes place, and that recall favors views of the target square that would be obtained when approaching it from the current recall location. In two separate experiments in an outdoor urban environment, pedestrians were approached at various interview locations and asked to draw sketch maps of one of two well-known squares. Orientations of the sketch map productions depended significantly on distance and direction of the interview location from the target square, i.e. different views were recalled at different locations. Further analysis showed that location-dependent recall is related to the respective approach direction when imagining a walk from the interview location to the target square. The results are consistent with a view-based model of spatial long-term and working memories and their interplay. PMID:25409437
Long-Term Dynamics of Autonomous Fractional Differential Equations
NASA Astrophysics Data System (ADS)
Liu, Tao; Xu, Wei; Xu, Yong; Han, Qun
This paper aims to investigate long-term dynamic behaviors of autonomous fractional differential equations with effective numerical method. The long-term dynamic behaviors predict where systems are heading after long-term evolution. We make some modification and transplant cell mapping methods to autonomous fractional differential equations. The mapping time duration of cell mapping is enlarged to deal with the long memory effect. Three illustrative examples, i.e. fractional Lotka-Volterra equation, fractional van der Pol oscillator and fractional Duffing equation, are studied with our revised generalized cell mapping method. We obtain long-term dynamics, such as attractors, basins of attraction, and saddles. Compared with some existing stability and numerical results, the validity of our method is verified. Furthermore, we find that the fractional order has its effect on the long-term dynamics of autonomous fractional differential equations.
'The apple doesn't fall far from the tree': the role of parents in chronic disease self-management.
Orrell-Valente, Joan K; Cabana, Michael D
2008-12-01
Medical nonadherence has been termed the "Achilles' heel of modern healthcare." In considering the need to improve medical adherence among chronically ill children, it is necessary to understand parent adherence. Parents have long been acknowledged to be the primary socialization agents in children's development across the various domains of functioning. Through communication of their beliefs, the behavior they model, and direct training, parents exert a powerful influence on the development of children's beliefs and behavior. Adherence may be similarly conceptualized as a socialization process, in which parents influence the development of children's beliefs and behavior regarding their eventual disease self-management. Given this perspective, it is important for clinicians to emphasize the need for parental adherence to a child's treatment regimen. An increased focus on parental adherence will require an investment of time and effort that will pay dividends in the long term.
Critical neural networks with short- and long-term plasticity.
Michiels van Kessenich, L; Luković, M; de Arcangelis, L; Herrmann, H J
2018-03-01
In recent years self organized critical neuronal models have provided insights regarding the origin of the experimentally observed avalanching behavior of neuronal systems. It has been shown that dynamical synapses, as a form of short-term plasticity, can cause critical neuronal dynamics. Whereas long-term plasticity, such as Hebbian or activity dependent plasticity, have a crucial role in shaping the network structure and endowing neural systems with learning abilities. In this work we provide a model which combines both plasticity mechanisms, acting on two different time scales. The measured avalanche statistics are compatible with experimental results for both the avalanche size and duration distribution with biologically observed percentages of inhibitory neurons. The time series of neuronal activity exhibits temporal bursts leading to 1/f decay in the power spectrum. The presence of long-term plasticity gives the system the ability to learn binary rules such as xor, providing the foundation of future research on more complicated tasks such as pattern recognition.
Critical neural networks with short- and long-term plasticity
NASA Astrophysics Data System (ADS)
Michiels van Kessenich, L.; Luković, M.; de Arcangelis, L.; Herrmann, H. J.
2018-03-01
In recent years self organized critical neuronal models have provided insights regarding the origin of the experimentally observed avalanching behavior of neuronal systems. It has been shown that dynamical synapses, as a form of short-term plasticity, can cause critical neuronal dynamics. Whereas long-term plasticity, such as Hebbian or activity dependent plasticity, have a crucial role in shaping the network structure and endowing neural systems with learning abilities. In this work we provide a model which combines both plasticity mechanisms, acting on two different time scales. The measured avalanche statistics are compatible with experimental results for both the avalanche size and duration distribution with biologically observed percentages of inhibitory neurons. The time series of neuronal activity exhibits temporal bursts leading to 1 /f decay in the power spectrum. The presence of long-term plasticity gives the system the ability to learn binary rules such as xor, providing the foundation of future research on more complicated tasks such as pattern recognition.
What Ever Happened To The ‘Cool’ Kids? Long-Term Sequelae Of Early Adolescent Pseudomature Behavior
Allen, Joseph P.; Schad, Megan M.; Oudekerk, Barbara; Chango, Joanna
2014-01-01
Pseudomature behavior—ranging from minor delinquency to precocious romantic involvement—is widely viewed as a nearly normative feature of adolescence. When such behavior occurs early in adolescence, however, it was hypothesized to reflect a misguided overemphasis upon impressing peers and was considered likely to predict long-term adjustment problems. In a multi-method, multi-reporter study following a community sample of 184 adolescents from age 13 to 23, early adolescent pseudomature behavior was linked cross-sectionally to a heightened desire for peer popularity and to short-term success with peers. Longitudinal results, however, supported the study’s central hypothesis: Early adolescent pseudomature behavior predicted long-term difficulties in close relationships, as well as significant problems with alcohol and substance use, and elevated levels of criminal behavior. PMID:24919537
Hu, Ruofei; Cancela, Jorge; Arredondo Waldmeyer, Maria Teresa; Cea, Gloria; Vlachopapadopoulou, Elpis-Athina; Fotiadis, Dimitrios I; Fico, Giuseppe
2016-01-01
Childhood obesity is becoming one of the 21st century's most important public health problems. Nowadays, the main treatment of childhood obesity is behavior intervention that aims at improve children's lifestyle to arrest the disease. Information and communication technologies (ICTs) have not been widely employed in this intervention, and most of existing ICTs systems are not having a long-term effect. The purpose of this paper is to define a system to support family-based intervention through a state-of-the-art analysis of family-based interventions and related technological solutions first, and then using the analytic hierarchy process to derive a childhood obesity family-based behavior intervention model, and finally to provide a prototype of a system called OB CITY. The system makes use of applied behavior analysis, affective computing technologies, as well as serious game and gamification techniques, to offer long term services in all care dimensions of the family-based behavioral intervention aiming to provide positive effects to the treatment of childhood obesity.
Solar Cycle Response and Long-Term Trends in the Mesospheric Metal Layers
NASA Technical Reports Server (NTRS)
Dawkins, E. C. M.; Plane, J. M. C.; Chipperfield, M.; Feng, W.; Marsh, D. R.; Hoffner, J.; Janches, D.
2016-01-01
The meteoric metal layers (Na, Fe, and K) which form as a result of the ablation of incoming meteors act as unique tracers for chemical and dynamical processes that occur within the upper mesosphere lower thermosphere region. In this work, we examine whether these metal layers are sensitive Fe indicators of decadal long-term changes within the upper atmosphere. Output from a whole-atmosphere climate model is used to assess the response of the Na, K, and Fe layers across a 50 year period (1955-2005). At short timescales, the K layer has previously been shown to exhibit a very different seasonal behavior compared to the other metals. Here we show that this unusual behavior is also exhibited at longer time scales (both the 11 year solar cycle and 50 year periods), where K displays a much more pronounced response to atmospheric temperature changes than either Na or Fe. The contrasting solar cycle behavior of the K and Na layers predicted by the model is confirmed using satellite and lidar observations for the period 2004-2013.
Synaptic long-term potentiation realized in Pavlov's dog model based on a NiOx-based memristor
NASA Astrophysics Data System (ADS)
Hu, S. G.; Liu, Y.; Liu, Z.; Chen, T. P.; Yu, Q.; Deng, L. J.; Yin, Y.; Hosaka, Sumio
2014-12-01
Synaptic Long-Term Potentiation (LTP), which is a long-lasting enhancement in signal transmission between neurons, is widely considered as the major cellular mechanism during learning and memorization. In this work, a NiOx-based memristor is found to be able to emulate the synaptic LTP. Electrical conductance of the memristor is increased by electrical pulse stimulation and then spontaneously decays towards its initial state, which resembles the synaptic LTP. The lasting time of the LTP in the memristor can be estimated with the relaxation equation, which well describes the conductance decay behavior. The LTP effect of the memristor has a dependence on the stimulation parameters, including pulse height, width, interval, and number of pulses. An artificial network consisting of three neurons and two synapses is constructed to demonstrate the associative learning and LTP behavior in extinction of association in Pavlov's dog experiment.
Fedotova, Julia; Pivina, Svetlana; Sushko, Anastasia
2017-01-01
The present preclinical study was created to determine the therapeutic effects of vitamin D hormone treatment as an adjunctive therapy alone or in a combination with low dose of 17β-estradiol (17β-E2) on anxiety-like behavior in female rats with long-term absence of estrogen. Accordingly, the aim of the current study was to examine the effects of chronic cholecalciferol administration (1.0, 2.5 or 5.0 mg/kg subcutaneously, SC, once daily, for 14 days) on the anxiety-like state after long-term ovariectomy in female rats. Twelve weeks postovariectomy, cholecalciferol was administered to ovariectomized (OVX) rats and OVX rats treated with 17β-E2 (0.5 µg/rat SC, once daily, for 14 days). Anxiety-like behavior was assessed in the elevated plus maze (EPM) and the light/dark test (LDT), and locomotor and grooming activities were tested in the open field test (OFT). Cholecalciferol at two doses of 1.0 and 2.5 mg/kg alone or in combination with 17β-E2 produced anxiolytic-like effects in OVX rats as evidenced in the EPM and the LDT, as well as increased grooming activity in the OFT. Our results indicate that cholecalciferol, at two doses of 1.0 and 2.5 mg/kg, has a profound anxiolytic-like effects in the experimental rat model of long-term estrogen deficiency. PMID:28054941
Biosafety assessment of Gd@C82(OH)22 nanoparticles on Caenorhabditis elegans
NASA Astrophysics Data System (ADS)
Zhang, Wendi; Sun, Baoyun; Zhang, Longze; Zhao, Baolu; Nie, Guangjun; Zhao, Yuliang
2011-06-01
Gd@C82(OH)22, a water-soluble endohedral metallofullerene derivative, has been proven to possess significant antineoplastic activity in mice. Toxicity studies of the nanoparticle have shown some evidence of low or non toxicity in mice and cell models. Here we employed Caenorhabditis elegans (C. elegans) as a model organism to further evaluate the short- and long-term toxicity of Gd@C82(OH)22 and possible behavior changes under normal and stress culture conditions. With treatment of Gd@C82(OH)22 at 0.01, 0.1, 1.0 and 10 μg ml-1 within one generation (short-term), C. elegans showed no significant decrease in longevity or thermotolerance compared to the controls. Furthermore, when Gd@C82(OH)22 treatment was extended up to six generations (long-term), non-toxic effects to the nematodes were found. In addition, data from body length measurement, feeding rate and egg-laying assays with short-term treatment demonstrated that the nanoparticles have no significant impact on the individual growth, feeding behavior and reproductive ability, respectively. In summary, this work has shown that Gd@C82(OH)22 is tolerated well by worms and it has no apparent toxic effects on longevity, stress resistance, growth and behaviors that were observed in both adult and young worms. Our work lays the foundations for further developments of this anti-neoplastic agent for clinical applications.
Electrochemical Corrosion Studies for Modeling Metallic Waste Form Release Rates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Poineau, Frederic; Tamalis, Dimitri
The isotope 99Tc is an important fission product generated from nuclear power production. Because of its long half-life (t 1/2 = 2.13 ∙ 10 5 years) and beta-radiotoxicity (β⁻ = 292 keV), it is a major concern in the long-term management of spent nuclear fuel. In the spent nuclear fuel, Tc is present as an alloy with Mo, Ru, Rh, and Pd called the epsilon-phase, the relative amount of which increases with fuel burn-up. In some separation schemes for spent nuclear fuel, Tc would be separated from the spent fuel and disposed of in a durable waste form. Technetium wastemore » forms under consideration include metallic alloys, oxide ceramics and borosilicate glass. In the development of a metallic waste form, after separation from the spent fuel, Tc would be converted to the metal, incorporated into an alloy and the resulting waste form stored in a repository. Metallic alloys under consideration include Tc–Zr alloys, Tc–stainless steel alloys and Tc–Inconel alloys (Inconel is an alloy of Ni, Cr and iron which is resistant to corrosion). To predict the long-term behavior of the metallic Tc waste form, understanding the corrosion properties of Tc metal and Tc alloys in various chemical environments is needed, but efforts to model the behavior of Tc metallic alloys are limited. One parameter that should also be considered in predicting the long-term behavior of the Tc waste form is the ingrowth of stable Ru that occurs from the radioactive decay of 99Tc ( 99Tc → 99Ru + β⁻). After a geological period of time, significant amounts of Ru will be present in the Tc and may affect its corrosion properties. Studying the effect of Ru on the corrosion behavior of Tc is also of importance. In this context, we studied the electrochemical behavior of Tc metal, Tc-Ni alloys (to model Tc-Inconel alloy) and Tc-Ru alloys in acidic media. The study of Tc-U alloys has also been performed in order to better understand the nature of Tc in metallic spent fuel. Computational modeling and simulations were performed to shed light on experimental results and explain structural and kinetics trends.« less
An Exploratory Study of the Butterfly Effect Using Agent-Based Modeling
NASA Technical Reports Server (NTRS)
Khasawneh, Mahmoud T.; Zhang, Jun; Shearer, Nevan E. N.; Rodriquez-Velasquez, Elkin; Bowling, Shannon R.
2010-01-01
This paper provides insights about the behavior of chaotic complex systems, and the sensitive dependence of the system on the initial starting conditions. How much does a small change in the initial conditions of a complex system affect it in the long term? Do complex systems exhibit what is called the "Butterfly Effect"? This paper uses an agent-based modeling approach to address these questions. An existing model from NetLogo library was extended in order to compare chaotic complex systems with near-identical initial conditions. Results show that small changes in initial starting conditions can have a huge impact on the behavior of chaotic complex systems. The term the "butterfly effect" is attributed to the work of Edward Lorenz [1]. It is used to describe the sensitive dependence of the behavior of chaotic complex systems on the initial conditions of these systems. The metaphor refers to the notion that a butterfly flapping its wings somewhere may cause extreme changes in the ecological system's behavior in the future, such as a hurricane.
The effects of physical aging at elevated temperatures on the viscoelastic creep on IM7/K3B
NASA Technical Reports Server (NTRS)
Gates, Thomas S.; Feldman, Mark
1994-01-01
Physical aging at elevated temperature of the advanced composite IM7/K3B was investigated through the use of creep compliance tests. Testing consisted of short term isothermal, creep/recovery with the creep segments performed at constant load. The matrix dominated transverse tensile and in-plane shear behavior were measured at temperatures ranging from 200 to 230 C. Through the use of time based shifting procedures, the aging shift factors, shift rates and momentary master curve parameters were found at each temperature. These material parameters were used as input to a predictive methodology, which was based upon effective time theory and linear viscoelasticity combined with classical lamination theory. Long term creep compliance test data was compared to predictions to verify the method. The model was then used to predict the long term creep behavior for several general laminates.
Lee, Chung-Hao; Rabbah, Jean-Pierre; Yoganathan, Ajit P.; Gorman, Robert C.; Gorman, Joseph H.
2016-01-01
Recent long-term studies showed an unsatisfactory recurrence rate of severe mitral regurgitation 3–5 years after surgical repair, suggesting that excessive tissue stresses and the resulting strain-induced tissue failure are potential etiological factors controlling the success of surgical repair for treating mitral valve (MV) diseases. We hypothesized that restoring normal MV tissue stresses in MV repair techniques would ultimately lead to improved repair durability through the restoration of MV normal homeostatic state. Therefore, we developed a micro- and macro- anatomically accurate MV finite element model by incorporating actual fiber microstructural architecture and a realistic structure-based constitutive model. We investigated MV closing behaviors, with extensive in vitro data used for validating the proposed model. Comparative and parametric studies were conducted to identify essential model fidelity and information for achieving desirable accuracy. More importantly, for the first time, the interrelationship between the local fiber ensemble behavior and the organ-level MV closing behavior was investigated using a computational simulation. These novel results indicated not only the appropriate parameter ranges, but also the importance of the microstructural tuning (i.e., straightening and re-orientation) of the collagen/elastin fiber networks at the macroscopic tissue level for facilitating the proper coaptation and natural functioning of the MV apparatus under physiological loading at the organ level. The proposed computational model would serve as a logical first step toward our long-term modeling goal—facilitating simulation-guided design of optimal surgical repair strategies for treating diseased MVs with significantly enhanced durability. PMID:25947879
Using Wavelets to Evaluate Persistence of High Frequency Hydrologic and Hydrochemistry Signals
NASA Astrophysics Data System (ADS)
Koirala, S. R.; Gentry, R. W.
2009-12-01
In the area of sustainability science, it is becoming increasingly important to understand the basal condition of a natural system, and its long-term behavior. Research is needed to better understand the temporal scaling of hydrochemistry in streams and watersheds and its relationship to the hydrologic factors that influence its behavior. Persistence of dissolved chemicals in streams has been demonstrated to be linked to certain hydrologic processes, such as interactions between hydrologic units and storage in surface or sub-surface systems. In this study, wavelet analyses provided a novel theoretical basis for insights into long-term hydrochemistry behavior in an east Tennessee watershed. Temporal analyses were conducted on weekly time series data of hydrochemistry (nitrate, chloride, sulfate and calcium concentrations) collected from November 1995 to December 2005 at the West Fork of Walker Branch in Oak Ridge, Tennessee. Hydrochemistry plays an important role in ecosystem services, particularly nitrate, and in general the signal responses can be complex. The signals in this study were modeled using a wavelet approach as a mechanism for evaluating short-and long term temporal effects. The Walker Branch conceptual hydrology model is augmented by these results that show characteristic periodicities or structures for flowpath lengths in the vadose zone (< 20 week period), saturated zone (20 to 50 week period) and bedrock zone (> 50 week period) with implications for hydrochemistry within the watershed. In general, time series signals of watershed hydrochemistry may provide clues as to broad environmental, ecological and economic impacts at the basin scale.
Convergence of Weak Kähler-Ricci Flows on Minimal Models of Positive Kodaira Dimension
NASA Astrophysics Data System (ADS)
Eyssidieux, Phylippe; Guedj, Vincent; Zeriahi, Ahmed
2018-02-01
Studying the behavior of the Kähler-Ricci flow on mildly singular varieties, one is naturally lead to study weak solutions of degenerate parabolic complex Monge-Ampère equations. In this article, the third of a series on this subject, we study the long term behavior of the normalized Kähler-Ricci flow on mildly singular varieties of positive Kodaira dimension, generalizing results of Song and Tian who dealt with smooth minimal models.
Acceptance and relationship context: a model of substance use disorder treatment outcome.
Gifford, Elizabeth V; Ritsher, Jennifer B; McKellar, John D; Moos, Rudolf H
2006-08-01
This study presented and tested a model of behavior change in long-term substance use disorder recovery, the acceptance and relationship context (ARC) model. The model specifies that acceptance-based behavior and constructive social relationships lead to recovery, and that treatment programs with supportive, involved relationships facilitate the development of these factors. This study used a prospective longitudinal naturalistic design and controlled for baseline levels of study variables. The model was tested on a sample of 2549 patients in 15 residential substance use disorder treatment programs. Acceptance-based responding (ABR), social relationship quality (SRQ), treatment program alliance (TPA) and substance use-related impairment were assessed using interviews and self-report questionnaires. TPA predicted ABR and SRQ and, in turn, ABR predicted better 2-year and 5-year treatment outcomes. The baseline-controlled model accounted for 41% of the variance in outcome at 2-year follow-up and 28% of the variance in outcome at 5-year follow-up. CONCLUSIONS Patients from treatment programs with an affiliative relationship network are more likely to respond adaptively to internal states associated previously with substance use, develop constructive social relationships and achieve long-term treatment benefits.
Lucantonio, Federica; Caprioli, Daniele; Schoenbaum, Geoffrey
2014-01-01
Cocaine addiction is a complex and multidimensional process involving a number of behavioral and neural forms of plasticity. The behavioral transition from voluntary drug use to compulsive drug taking may be explained at the neural level by drug-induced changes in function or interaction between a flexible planning system, associated with prefrontal cortical regions, and a rigid habit system, associated with the striatum. The dichotomy between these two systems is operationalized in computational theory by positing model-based and model-free learning mechanisms, the former relying on an "internal model" of the environment and the latter on pre-computed or cached values to control behavior. In this review, we will suggest that model-free and model-based learning mechanisms appear to be differentially affected, at least in the case of psychostimulants such as cocaine, with the former being enhanced while the latter are disrupted. As a result, the behavior of long-term drug users becomes less flexible and responsive to the desirability of expected outcomes and more habitual, based on the long history of reinforcement. To support our specific proposal, we will review recent neural and behavioral evidence on the effect of psychostimulant exposure on orbitofrontal and dorsolateral striatum structure and function. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'. Published by Elsevier Ltd.
The fate of organic micropollutants during long-term/long-distance river bank filtration.
Hamann, Enrico; Stuyfzand, Pieter J; Greskowiak, Janek; Timmer, Harrie; Massmann, Gudrun
2016-03-01
The fate of organic micropollutants during long-term/long-distance river bank filtration (RBF) at a temporal scale of several years was investigated along a row of monitoring wells perpendicular to the Lek River (the Netherlands). Out of 247 compounds, which were irregularly analyzed in the period 1999-2013, only 15 were detected in both the river and river bank observation wells. Out of these, 10 compounds (1,4-dioxan, 1,5-naphthalene disulfonate (1,5-NDS), 2-amino-1,5-NDS, 3-amino-1,5-NDS, AOX, carbamazepine, EDTA, MTBE, toluene and triphenylphosphine oxide) showed fully persistent behavior (showing no concentration decrease at all), even after 3.6 years transit time. The remaining 5 compounds (1,3,5-naphthalene trisulfonate (1,3,5-NTS), 1,3,6-NTS, diglyme, iopamidol, triglyme) were partially removed. Their reactive transport parameters (removal rate constants/half-lives, retardation coefficients) were inferred from numerical modeling. In addition, maximum half-lives for 14 of the fully removed compounds, for which the data availability was sufficient to deduce 100% removal during sub-surface passage, were approximated based on travel times to the nearest well. The study is one of very few reporting on the long-term field-scale behavior of organic micropollutants. It highlights the efficiency of RBF for water quality improvement as a pre-treatment step for drinking water production. However, it also shows the very persistent behavior of various compounds in groundwater. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Rubinstein, Justin L.; Ellsworth, William L.; Beeler, Nicholas M.; Kilgore, Brian D.; Lockner, David A.; Savage, Heather M.
2012-02-01
The behavior of individual stick-slip events observed in three different laboratory experimental configurations is better explained by a "memoryless" earthquake model with fixed inter-event time or fixed slip than it is by the time- and slip-predictable models for earthquake occurrence. We make similar findings in the companion manuscript for the behavior of natural repeating earthquakes. Taken together, these results allow us to conclude that the predictions of a characteristic earthquake model that assumes either fixed slip or fixed recurrence interval should be preferred to the predictions of the time- and slip-predictable models for all earthquakes. Given that the fixed slip and recurrence models are the preferred models for all of the experiments we examine, we infer that in an event-to-event sense the elastic rebound model underlying the time- and slip-predictable models does not explain earthquake behavior. This does not indicate that the elastic rebound model should be rejected in a long-term-sense, but it should be rejected for short-term predictions. The time- and slip-predictable models likely offer worse predictions of earthquake behavior because they rely on assumptions that are too simple to explain the behavior of earthquakes. Specifically, the time-predictable model assumes a constant failure threshold and the slip-predictable model assumes that there is a constant minimum stress. There is experimental and field evidence that these assumptions are not valid for all earthquakes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wildung, R E; Drucker, H
Any assessment of the long-term behavior of the transuranics in the terrestrial environment must be based on determination of the factors influencing solubility in soil. The influence of soil properties and abiotic and biotic processes on the long-term solubility of the transuranics entering soils is reviewed in detail. Principal emphasis is directed toward the role of soil microorganisms. Emphasis is given to plutonium, but, where possible, the available information is used to discuss long-term behavior of other transuranics.
ERIC Educational Resources Information Center
Hongu, Nobuko; Kataura, Martha P.; Block, Linda M.
2011-01-01
This article helps Extension professionals guide individuals in a successful long-term weight loss program. A program should focus on behavioral changes (improving eating habits and physical activity), not just weight loss. In order to do this, Extension professionals should implement behavior change strategies that motivate individuals to…
Very Long Term Oxidation of Titanium Aluminides Investigated
NASA Technical Reports Server (NTRS)
Locci, Ivan E.; Brady, Michael P.; Smialek, James L.; Retallick, William B.
2000-01-01
Titanium aluminides (TiAl) are of great interest for intermediate-temperature (600 to 850 C) aerospace and power-generation applications because they offer significant weight savings over today's nickel alloys. TiAl alloys are being investigated for low-pressure turbine blade applications, exhaust nozzle components, and compressor cases in advanced subsonic and supersonic engines. Significant progress has been made in understanding the fundamental aspects of the oxidation behavior of binary TiAl alloys. However, most of this work has concentrated on short term (<1000 hr), high-temperature (900 to 1000 C) exposures. Also, there is not much data available in the literature regarding the oxidation behavior of the quaternary and higher order engineering alloys. This is especially true for the very long term, low-temperature conditions likely to be experienced during aerospace applications. An investigation at the NASA Glenn Research Center at Lewis Field was undertaken to characterize the long-term oxidation behavior of various model and advanced titanium aluminides for periods up to 7000 hr at 704 C in air using a high-resolution field emission scanning electron microscope. Also, a unique surface treatment technique developed to improve the oxidation resistance of TiAl was evaluated. The alloys included in this investigation are listed in the table. The table also shows typical alloy compositions and the specific weight changes and scale thickness measured for each alloy after exposure to 700 C for 7000 hr in air.
Lee, Kyung-Suk; Choi, Ok-Joo; Kim, Joon-Ho
2017-09-01
Children who have experienced negative rearing behaviors show a lack of self-confidence due to emotional instability and are reserved in interpersonal relationships. This can lead to failure in social adaptation and a high risk of depression, suicide, criminal acts, and anti-social behaviors. Therefore, this study aims to analyze the effects of experiencing negative parental rearing behaviors, such as neglect and abuse, on adolescents' social withdrawal and aggression, by utilizing multivariate latent growth models. Data from the Korean Children and Youth Panel Study (KCYPS), a survey conducted by the National Youth Policy Institute targeting a cohort of three different age groups (grade 1, grade 4, and grade 7), from 2010 to 2016 was used. Multi-stage stratified sampling methods were used in the KCYPS, which surveyed the students and parents of the selected grade levels. This study analyzed the data for grade 7, from second year (grade 8) to fourth year (grade 10). Negative rearing experiences had a significant effect on social withdrawal and aggression, and this influence was shown to persist over the long term. This study examined the long-term developmental trajectory in the relationship between risk factors for adolescent development. Furthermore, the relationship between risk factors was shown to have not only short term but long-term effects as well, which reinforces the limitations of previous studies.
Lee, Kyung-Suk; Choi, Ok-Joo
2017-01-01
Background Children who have experienced negative rearing behaviors show a lack of self-confidence due to emotional instability and are reserved in interpersonal relationships. This can lead to failure in social adaptation and a high risk of depression, suicide, criminal acts, and anti-social behaviors. Therefore, this study aims to analyze the effects of experiencing negative parental rearing behaviors, such as neglect and abuse, on adolescents' social withdrawal and aggression, by utilizing multivariate latent growth models. Methods Data from the Korean Children and Youth Panel Study (KCYPS), a survey conducted by the National Youth Policy Institute targeting a cohort of three different age groups (grade 1, grade 4, and grade 7), from 2010 to 2016 was used. Multi-stage stratified sampling methods were used in the KCYPS, which surveyed the students and parents of the selected grade levels. This study analyzed the data for grade 7, from second year (grade 8) to fourth year (grade 10). Results Negative rearing experiences had a significant effect on social withdrawal and aggression, and this influence was shown to persist over the long term. Conclusion This study examined the long-term developmental trajectory in the relationship between risk factors for adolescent development. Furthermore, the relationship between risk factors was shown to have not only short term but long-term effects as well, which reinforces the limitations of previous studies. PMID:29026488
Business Students' Choice of Short-Term or Long-Term Study Abroad Opportunities
ERIC Educational Resources Information Center
Fitzsimmons, Stacey R.; Flanagan, David J.; Wang, Xiaodan
2013-01-01
Recent years have seen a proliferation of short-term study abroad opportunities. Although they are both supplementing and replacing semester-long study abroad programs, research has focused primarily on semester (long-term) programs. We draw on the theory of planned behavior (TPB) to explore factors that predict why students choose long-term and…
ERIC Educational Resources Information Center
Elliot, Diane L.; Goldberg, Linn; Moe, Esther L.; DeFrancesco, Carol A.; Durham, Melissa B.; McGinnis, Wendy; Lockwood, Chondra
2008-01-01
Adolescence and emerging adulthood are critical windows for establishing life-long behaviors. We assessed long-term outcomes of a prospective randomized harm reduction/health promotion program for female high school athletes. The intervention's immediate beneficial effects on diet pill use and unhealthy eating behaviors have been reported;…
NASA Astrophysics Data System (ADS)
Shinoda, Yukio; Yabe, Kuniaki; Tanaka, Hideo; Akisawa, Atsushi; Kashiwagi, Takao
In this paper we consider that there are two economical social behaviors when new technologies are introduced. One is on the short-term economic basis, the other one is on the long-tem economic basis. If we consider a learning curve on the technology, it is more economical than short-term behavior to accelerate the introduction of the technology much wider in the earlier term than that on short-term economic basis. The costs in the accelerated term are higher, but the introduction costs in the later terms are cheaper by learning curve. This paper focuses on the plug-in hybrid electric vehicles (PHEVs). The ways to derive the results on short-term economic basis and the results on long-term economic basis are shown. The result of short-term behaviors can be derived by using the iteration method in which the battery costs in every term are adjusted to the learning curve. The result of long-term behaviors can be derived by seeking to the way where the amount of battery capacity is increased. We also estimate that how much subsidy does it need to get close to results on the long-term economic basis when social behavior is on the short-term economic basis. We assume subsidy for PHEV's initial costs, which can be financed by charging fee on petroleum consumption. In that case, there is no additional cost in the system. We show that the greater the total amount of money to that subsidy is, the less the amount of both CO2 emissions and system costs.
NASA Astrophysics Data System (ADS)
Asadollahi, Parisa; Li, Jian
2016-04-01
Understanding the dynamic behavior of complex structures such as long-span bridges requires dense deployment of sensors. Traditional wired sensor systems are generally expensive and time-consuming to install due to cabling. With wireless communication and on-board computation capabilities, wireless smart sensor networks have the advantages of being low cost, easy to deploy and maintain and therefore facilitate dense instrumentation for structural health monitoring. A long-term monitoring project was recently carried out for a cable-stayed bridge in South Korea with a dense array of 113 smart sensors, which feature the world's largest wireless smart sensor network for civil structural monitoring. This paper presents a comprehensive statistical analysis of the modal properties including natural frequencies, damping ratios and mode shapes of the monitored cable-stayed bridge. Data analyzed in this paper is composed of structural vibration signals monitored during a 12-month period under ambient excitations. The correlation between environmental temperature and the modal frequencies is also investigated. The results showed the long-term statistical structural behavior of the bridge, which serves as the basis for Bayesian statistical updating for the numerical model.
Adolescents' media exposure may increase their cyberbullying behavior: a longitudinal study.
den Hamer, Anouk H; Konijn, Elly A
2015-02-01
The aim of this study was to examine the effect of adolescents' exposure to media portraying antisocial and risk behavior on cyberbullying behavior over time. Previous research established relatively high prevalence of cyberbullying behavior among adolescents, although not much is known about the possible predictors of cyberbullying behavior. This study examines the long-term effects of media exposure herein. Furthermore, we examined whether boys and girls differ in this respect. The long-term effects were tested in a longitudinal design with three waves (N = 1,005; age range, 11-17 years; 49% boys). Measured variables: cyberbullying behavior and exposure to media with antisocial and risk behavior content. Results of mixed-model analyses showed that higher levels of exposure to media with antisocial and risk behavior content significantly contributed to higher initial rates of cyberbullying behavior. Moreover, an increase in exposure to antisocial media content was significantly related to an increase in cyberbullying behavior over time. For both boys and girls, higher exposure to antisocial and risk behavior media content increases cyberbullying behavior over time though more clearly for boys than for girls. This study provided empirical support for the amplifying effect of exposure to antisocial media content on adolescents' cyberbullying behavior over time. Results are discussed in view of adolescents' media use and the larger theoretical framework. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
West, Amy E.; Henry, David B.; Pavuluri, Mani N.
2007-01-01
Objective: The chronic and refractory course of pediatric bipolar disorder merits the study of adjunctive psychosocial interventions designed to facilitate long-term improvements. The objective of this study is to conduct a pilot study of a maintenance model of the child- and family-focused cognitive-behavioral therapy program (CFF-CBT), which…
Time-Dependent Behavior of Diabase and a Nonlinear Creep Model
NASA Astrophysics Data System (ADS)
Yang, Wendong; Zhang, Qiangyong; Li, Shucai; Wang, Shugang
2014-07-01
Triaxial creep tests were performed on diabase specimens from the dam foundation of the Dagangshan hydropower station, and the typical characteristics of creep curves were analyzed. Based on the test results under different stress levels, a new nonlinear visco-elasto-plastic creep model with creep threshold and long-term strength was proposed by connecting an instantaneous elastic Hooke body, a visco-elasto-plastic Schiffman body, and a nonlinear visco-plastic body in series mode. By introducing the nonlinear visco-plastic component, this creep model can describe the typical creep behavior, which includes the primary creep stage, the secondary creep stage, and the tertiary creep stage. Three-dimensional creep equations under constant stress conditions were deduced. The yield approach index (YAI) was used as the criterion for the piecewise creep function to resolve the difficulty in determining the creep threshold value and the long-term strength. The expression of the visco-plastic component was derived in detail and the three-dimensional central difference form was given. An example was used to verify the credibility of the model. The creep parameters were identified, and the calculated curves were in good agreement with the experimental curves, indicating that the model is capable of replicating the physical processes.
Shahar, Irit; Mendelson, Gad; Ben Natan, Merav
2017-04-01
The factors affecting influenza vaccine uptake among nurses might vary between different medical facilities. The purpose of the present study was to explore factors that affect the intention of nurses at a long-term care facility to receive the influenza vaccine and whether the health belief model predicts this intention. In this cross-sectional quantitative correlational study, a convenience sample of 150 nurses employed at a large long-term care facility in central Israel completed a questionnaire based on the health belief model. Data collection took place between January and February of 2016. Forty-two percent of the respondents reported having been vaccinated against influenza in the current year. The health belief model explained 53% of the variance (p < .01), with perceived (personal) benefits of the vaccine being the most significant factor. The number of times of receiving the influenza vaccine in the past was strongly correlated with the intention to receive the vaccine (p < .01). To improve nurses' compliance with influenza vaccination at long-term care facilities, we find that it is necessary to emphasize the benefits of vaccination and, particularly, the personal benefits. Annual vaccination behavior should be promoted to make it become a routine. © 2017 John Wiley & Sons Australia, Ltd.
Long-Term Effects of Neonatal Pain and Stress on Reactivity of the Nociceptive System.
Butkevich, I P; Mikhailenko, V A
2016-10-01
The influence of inflammatory pain and/or weaning stress at different terms of neonatal development on functional activity of the nociceptive system during adulthood was studied in rats. Repeated stress in 1-2-day-old rat pups (a premature baby model) enhanced pain sensitivity to peripheral inflammation in both males and females. Repeated inflammatory pain experienced by male pups aged 1-2 or 7-8 days (models of preterm and full-term baby), even in presence of mother, enhanced pain behavior under conditions of repeated inflammatory pain in adulthood. Pain sensitivity in adult animals before (hot plate test) and after formation of the inflammatory focus (formalin test) depended on the age when the animals were subjected to the injury, type of exposure, and on animal sex. The priority data obtained by us will help to understand the mechanisms of long-term effects of early injuries and are important for pediatricians and neonatologists.
Bartholow, Bruce D
2010-03-01
Numerous social-cognitive models posit that social behavior largely is driven by links between constructs in long-term memory that automatically become activated when relevant stimuli are encountered. Various response biases have been understood in terms of the influence of such "implicit" processes on behavior. This article reviews event-related potential (ERP) studies investigating the role played by cognitive control and conflict resolution processes in social-cognitive phenomena typically deemed automatic. Neurocognitive responses associated with response activation and conflict often are sensitive to the same stimulus manipulations that produce differential behavioral responses on social-cognitive tasks and that often are attributed to the role of automatic associations. Findings are discussed in the context of an overarching social cognitive neuroscience model in which physiological data are used to constrain social-cognitive theories.
Rorabaugh, Jacki M.; Stratford, Jennifer M.; Zahniser, Nancy R.
2014-01-01
Fructose accounts for 10% of daily calories in the American diet. Fructose, but not glucose, given intracerebroventricularly stimulates homeostatic feeding mechanisms within the hypothalamus; however, little is known about how fructose affects hedonic feeding centers. Repeated ingestion of sucrose, a disaccharide of fructose and glucose, increases neuronal activity in hedonic centers, the nucleus accumbens (NAc) shell and core, but not the hypothalamus. Rats given glucose in the intermittent access model (IAM) display signatures of hedonic feeding including bingeing and altered DA receptor (R) numbers within the NAc. Here we examined whether substituting fructose for glucose in this IAM produces bingeing behavior, alters DA Rs and activates hedonic and homeostatic feeding centers. Following long-term (21-day) exposure to the IAM, rats given 8–12% fructose solutions displayed fructose bingeing but unaltered DA D1R or D2R number. Fructose bingeing rats, as compared to chow bingeing controls, exhibited reduced NAc shell neuron activation, as determined by c-Fos-immunoreactivity (Fos-IR). This activation was negatively correlated with orexin (Orx) neuron activation in the lateral hypothalamus/perifornical area (LH/PeF), a brain region linking homeostatic to hedonic feeding centers. Following short-term (2-day) access to the IAM, rats exhibited bingeing but unchanged Fos-IR, suggesting only long-term fructose bingeing increases Orx release. In long-term fructose bingeing rats, pretreatment with the Ox1R antagonist SB-334867 (30 mg/kg; i.p.) equally reduced fructose bingeing and chow intake, resulting in a 50% reduction in calories. Similarly, in control rats, SB-334867 reduced chow/caloric intake by 60%. Thus, in the IAM, Ox1Rs appear to regulate feeding based on caloric content rather than palatability. Overall, our results, in combination with the literature, suggest individual monosaccharides activate distinct neuronal circuits to promote feeding behavior. Specifically, long-term fructose bingeing activates a hyperphagic circuit composed in part of NAc shell and LH/PeF Orx neurons. PMID:24736531
Microstructural Evolution of Thor™ 115 Creep-Strength Enhanced Ferritic Steel
NASA Astrophysics Data System (ADS)
Ortolani, Matteo; D'Incau, Mirco; Ciancio, Regina; Scardi, Paolo
2017-12-01
A new ferritic steel branded as Thor™ 115 has been developed to enhance high-temperature resistance. The steel design combines an improved oxidation resistance with long-term microstructural stability. The new alloy, cast to different product forms such as plates and tubes, was extensively tested to assess the high-temperature time-dependent mechanical behavior (creep). The main strengthening mechanism is precipitation hardening by finely dispersed carbide and nitride phases. Information on the evolution of secondary phases and time-temperature-precipitation behavior of the alloy, essential to ensure long-term property stability, was obtained by scanning transmission electron microscopy with energy dispersive spectroscopy, and by X-ray Powder Diffraction on specimens aged up to 50,000 hours. A thermodynamic modeling supports presentation and evaluation of the experimental results. The evolution of precipitates in the new alloy confirms the retention of the strengthening by secondary phases, even after long-term exposure at high temperature. The deleterious conversion of nitrides into Z phase is shown to be in line with, or even slower than that of the comparable ASME grade 91 steel.
The Shock and Vibration Digest. Volume 18, Number 7
1986-07-01
long-term dynamic irregularity of a soluble Los Alamos, NM, July 21-23, 1981 quantum mechanical model known as the Jaynes - Cummings model . The analysis...substructure models are obtained % substructure computation can be performed by approximating each state space vector as a independently of the other...Non- and rotational residual flexibilities at the inter- linear joint behavior is modeled by an equivalent face. Data were taken in the form of
ERIC Educational Resources Information Center
Huesmann, L. Rowell
2010-01-01
Over the past half century the mass media, including video games, have become important socializers of children. Observational learning theory has evolved into social-cognitive information processing models that explain that what a child observes in any venue has both short-term and long-term influences on the child's behaviors and cognitions. C.…
ERIC Educational Resources Information Center
Shen, April Chiung-Tao
2009-01-01
Objectives: This study investigated the joint long-term impact of witnessing interparental violence and experiencing child physical maltreatment on young adults' trauma symptoms and behavior problems. It also explored Chinese traditional beliefs as a possible contributor to young adults' trauma and behavior. Methods: This study used self-reporting…
A Bayesian formulation of behavioral control.
Huys, Quentin J M; Dayan, Peter
2009-12-01
Helplessness, a belief that the world is not subject to behavioral control, has long been central to our understanding of depression, and has influenced cognitive theories, animal models and behavioral treatments. However, despite its importance, there is no fully accepted definition of helplessness or behavioral control in psychology or psychiatry, and the formal treatments in engineering appear to capture only limited aspects of the intuitive concepts. Here, we formalize controllability in terms of characteristics of prior distributions over affectively charged environments. We explore the relevance of this notion of control to reinforcement learning methods of optimising behavior in such environments and consider how apparently maladaptive beliefs can result from normative inference processes. These results are discussed with reference to depression and animal models thereof.
Investigation of the Behavior of Hardening Masonry Exposed to Variable Stresses
Šlivinskas, Tomas; Jonaitis, Bronius; Marčiukaitis, Jonas Gediminas
2018-01-01
This paper analyzes the behavior of masonry under variable loads during execution (construction stage). It specifies the creep coefficient for calcium silicate brick masonry, presenting the research data of masonry deformation under variable and constant long-term loads. The interaction of separate layers of composite material in masonry is introduced and the formulae for determining long-term deformations are offered. The research results of masonry’s compressive strength and deformation properties under variable and constant long-term loads are presented. These are then compared to calculated ones. According to the presented comparison, the calculated long-term deformations coincide quite well with those determined experimentally. PMID:29710802
Investigation of the Behavior of Hardening Masonry Exposed to Variable Stresses.
Šlivinskas, Tomas; Jonaitis, Bronius; Marčiukaitis, Jonas Gediminas; Zavalis, Robertas
2018-04-28
This paper analyzes the behavior of masonry under variable loads during execution (construction stage). It specifies the creep coefficient for calcium silicate brick masonry, presenting the research data of masonry deformation under variable and constant long-term loads. The interaction of separate layers of composite material in masonry is introduced and the formulae for determining long-term deformations are offered. The research results of masonry’s compressive strength and deformation properties under variable and constant long-term loads are presented. These are then compared to calculated ones. According to the presented comparison, the calculated long-term deformations coincide quite well with those determined experimentally.
DOT National Transportation Integrated Search
2009-01-01
Early-age cracking, typically caused by drying shrinkage (and often coupled with autogenous and thermal : shrinkage), can have several detrimental effects on long-term behavior and durability. Cracking can also provide : ingress of water that can dri...
Zhu, Lei; Gonder, Jeffrey; Lin, Lei
2017-08-16
With the development of and advances in smartphones and global positioning system (GPS) devices, travelers’ long-term travel behaviors are not impossible to obtain. This study investigates the pattern of individual travel behavior and its correlation with social-demographic features. For different social-demographic groups (e.g., full-time employees and students), the individual travel behavior may have specific temporal-spatial-mobile constraints. The study first extracts the home-based tours, including Home-to-Home and Home-to-Non-Home, from long-term raw GPS data. The travel behavior pattern is then delineated by home-based tour features, such as departure time, destination location entropy, travel time, and driving time ratio. The travel behavior variabilitymore » describes the variances of travelers’ activity behavior features for an extended period. After that, the variability pattern of an individual’s travel behavior is used for estimating the individual’s social-demographic information, such as social-demographic role, by a supervised learning approach, support vector machine. In this study, a long-term (18-month) recorded GPS data set from Puget Sound Regional Council is used. The experiment’s result is very promising. In conclusion, the sensitivity analysis shows that as the number of tours thresholds increases, the variability of most travel behavior features converges, while the prediction performance may not change for the fixed test data.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Lei; Gonder, Jeffrey; Lin, Lei
With the development of and advances in smartphones and global positioning system (GPS) devices, travelers’ long-term travel behaviors are not impossible to obtain. This study investigates the pattern of individual travel behavior and its correlation with social-demographic features. For different social-demographic groups (e.g., full-time employees and students), the individual travel behavior may have specific temporal-spatial-mobile constraints. The study first extracts the home-based tours, including Home-to-Home and Home-to-Non-Home, from long-term raw GPS data. The travel behavior pattern is then delineated by home-based tour features, such as departure time, destination location entropy, travel time, and driving time ratio. The travel behavior variabilitymore » describes the variances of travelers’ activity behavior features for an extended period. After that, the variability pattern of an individual’s travel behavior is used for estimating the individual’s social-demographic information, such as social-demographic role, by a supervised learning approach, support vector machine. In this study, a long-term (18-month) recorded GPS data set from Puget Sound Regional Council is used. The experiment’s result is very promising. In conclusion, the sensitivity analysis shows that as the number of tours thresholds increases, the variability of most travel behavior features converges, while the prediction performance may not change for the fixed test data.« less
ERIC Educational Resources Information Center
Hunt, Hillary R.; Gross, Alan M.
2009-01-01
Obesity is a world-wide health concern approaching epidemic proportions. Successful long-term treatment involves a combination of bariatric surgery, diet, and exercise. Social cognitive models, such as the Theory of Reasoned Action (TRA) and the Theory of Planned Behavior (TPB), are among the most commonly tested theories utilized in the…
ERIC Educational Resources Information Center
Hutchens, Myiah J.; Eveland, William P., Jr.
2009-01-01
This report examines the effects of exposure to various elements of a civics curriculum on civic participation, two forms of political knowledge, internal political efficacy, political cynicism, news elaboration, discussion elaboration and various forms of interpersonal and mediated political communication behaviors. The data are based on a…
Chemotherapy-Induced Late Transgenerational Effects in Mice
Kujjo, Loro L.; Chang, Eun A.; Pereira, Ricardo J. G.; Dhar, Shilpa; Marrero-Rosado, Brenda; Sengupta, Satyaki; Wang, Hongbing; Cibelli, Jose B.; Perez, Gloria I.
2011-01-01
To our knowledge, there is no report on long-term reproductive and developmental side effects in the offspring of mothers treated with a widely used chemotherapeutic drug such as doxorubicin (DXR), and neither is there information on transmission of any detrimental effects to several filial generations. Therefore, the purpose of the present paper was to examine the long-term effects of a single intraperitoneal injection of DXR on the reproductive and behavioral performance of adult female mice and their progeny. C57BL/6 female mice (generation zero; G0) were treated with either a single intraperitoneal injection of DXR (G0-DXR) or saline (G0-CON). Data were collected on multiple reproductive parameters and behavioral analysis for anxiety, despair and depression. In addition, the reproductive capacity and health of the subsequent six generations were evaluated. G0-DXR females developed despair-like behaviors; delivery complications; decreased primordial follicle pool; and early lost of reproductive capacity. Surprisingly, the DXR-induced effects in oocytes were transmitted transgenerationally; the most striking effects being observed in G4 and G6, constituting: increased rates of neonatal death; physical malformations; chromosomal abnormalities (particularly deletions on chromosome 10); and death of mothers due to delivery complications. None of these effects were seen in control females of the same generations. Long-term effects of DXR in female mice and their offspring can be attributed to genetic alterations or cell-killing events in oocytes or, presumably, to toxicosis in non-ovarian tissues. Results from the rodent model emphasize the need for retrospective and long-term prospective studies of survivors of cancer treatment and their offspring. PMID:21437292
Prospective Predictors of Suicidal Behavior in BPD at 6 Year Follow-up
Soloff, Paul H.; Chiappetta, Laurel
2012-01-01
Objective Recurrent suicidal behavior is a defining characteristic of BPD. Although most patients achieve remission of suicidal behaviors over time, 3% to 10% die by suicide, raising the question of whether there is a high risk suicidal subtype in BPD. We are conducting the first longitudinal study of suicidal behavior in BPD to identify prospective predictors of suicide attempts, and characterize BPD patients at highest risk for suicide completion. Method Demographic, diagnostic, clinical and psychosocial risk factors assessed at baseline were examined for predictive association with medically significant suicide attempts using Cox proportional hazards models. Prospective predictors were defined for subjects completing 6 or more years in the study and compared to earlier intervals. Results Among 90 subjects, 25 (27.8%) made at least one suicide attempt in the interval, most occurring in the first two years. Risk of attempt was increased by: a.) low socioeconomic status, b.) poor psychosocial adjustment, c.) a family history of suicide d.) prior psychiatric hospitalization; e.) absence of any outpatient treatment prior to the attempt. Higher global functioning at baseline decreased risk. Conclusion Risk factors predictive of suicide attempts change over time. Acute stressors such as MDD were predictive only in the short term (12 mos.), while poor psychosocial functioning had persistent and long term effects on suicide risk. Half of BPD patients have poor psychosocial outcomes despite symptomatic improvement. A social and vocational rehabilitation model of treatment is needed to decrease suicide risk and optimize long term outcomes in BPD. PMID:22549208
Muñoz-Abellán, C; Andero, R; Nadal, R; Armario, A
2008-09-01
Exposure of rodents to cats or certain cat odors results in long-term behavioral effects reminiscent of enhanced anxiety that have been considered to model post-traumatic stress disorder. However, other severe stressors such as tail-shock or immobilization in wooden boards (IMO) appear to induce shorter lasting changes in anxiety. In addition, there are controversial results regarding the effects of urine/feces odors. In the present work, we studied in two experiments the relationship between the degree of stress experienced by the animals during exposure to IMO, urine odors or fur odors (as assessed by hypothalamic-pituitary-adrenal activation and plasma glucose) and the short- and long-term behavioral consequences. In the first experiment, rats were individually exposed for 15 min to a novel environment (white large cages) containing either clean cat litter (controls) or litter soiled by cats (urine odors). Half of the rats in each condition were left to freely explore the environment whereas the others were subjected to immobilization (IMO) within the cages. Although ACTH, corticosterone and glucose responses to IMO were much stronger than those to the white cages with clean litter or urine odors (which did not differ from each other), no effect of treatments on anxiety-like behavior in the elevated plus-maze (EPM) were found one week later. However, previous IMO exposure did cause sensitization of the ACTH response to the EPM. In the second experiment, the response to white large cages containing either no odor (controls), litter soiled by cats (urine odor) or a cloth impregnated with cat odor (fur odor) was compared. Urine and fur odors elicited similar ACTH and corticosterone responses that were higher than those of controls, but plasma glucose levels were slightly higher in rats exposed to fur odor. When compared to controls, activity was only diminished in the novel cages containing fur odor. Similarly, fur odor-exposed rats, but not those exposed to urine odor, showed signs of enhanced anxiety in the EPM seven days later, although the ACTH response to the EPM was similar in the three groups. The present data demonstrate: (a) a marked dissociation between the degree of ACTH, corticosterone and glucose responses to stressors and their long-term anxiety-like effects; (b) that the type of cat odor is critical in determining the short-term and long-term physiological and behavioral consequences of exposure; and (c) that plasma ACTH released during brief exposure to the EPM does not appear to reflect anxiety-like behavior.
Long-Lasting Neural and Behavioral Effects of Iron Deficiency in Infancy
Lozoff, Betsy; Beard, John; Connor, James; Felt, Barbara; Georgieff, Michael; Schallert, Timothy
2006-01-01
Infants are at high risk for iron deficiency and iron-deficiency anemia. This review summarizes evidence of long-term effects of iron deficiency in infancy. Follow-up studies from preschool age to adolescence report poorer cognitive, motor, and social-emotional function, as well as persisting neurophysiologic differences. Research in animal models points to mechanisms for such long-lasting effects. Potential mechanisms relate to effects of iron deficiency during brain development on neurometabolism, myelination, and neurotransmitter function. PMID:16770951
ERIC Educational Resources Information Center
Holmes, Megan R.
2013-01-01
Background: Children who have been exposed to intimate partner violence (IPV) experience a wide variety of short-term social adjustment and emotional difficulties, including externalizing behavioral problems such as aggression. While children are affected by IPV at all ages, little is known about the long-term consequences of IPV exposure at…
Addictive behaviors related to opioid use for chronic pain: a population-based study.
Højsted, Jette; Ekholm, Ola; Kurita, Geana Paula; Juel, Knud; Sjøgren, Per
2013-12-01
The growing body of research showing increased opioid use in patients with chronic pain coupled with concerns regarding addiction encouraged the development of this population-based study. The goal of the study was to investigate the co-occurrence of indicators of addictive behaviors in patients with chronic non-cancer pain in long-term opioid treatment. The study combined data from the individual-based Danish Health Survey in 2010 and the official Danish health and socio-economic, individual-based registers. From a simple random sample of 25,000 adults (16 years or older) living in Denmark, 13,281 individuals were analyzed through multiple logistic regression analyses to assess the association between chronic pain (lasting ≥6 months), opioid use, health behavior, and body mass index. Six potential addictive behaviors were identified: daily smoking; high alcohol intake; illicit drug use in the past year; obesity; long-term use of benzodiazepines; and long-term use of benzodiazepine-related drugs. At least 2 of the 6 addictive behaviors were observed in 22.6% of the long-term opioid users with chronic pain compared with 11.5% of the non-opioid users with chronic pain and 8.9% of the individuals without chronic pain. Thus, a strong association was demonstrated between long-term opioid use and the clustering of addictive behaviors. An intricate relationship between chronic pain, opioid use, and addictive behaviors was observed in this study, which deserves both clinical attention and further research. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Guo, Yunlong
This dissertation focuses on nonisothermal physical aging of polymers from both experimental and theoretical aspects. The study concentrates on pure polymers rather than fiber-reinforced composites; this step removes several complicating factors to simplify the study. It is anticipated that the findings of this work can then be applied to composite materials applications. The physical aging tests in this work are performed using a dynamic mechanical analyzer (DMA). The viscoelastic response of glassy polymers under various loading and thermal histories are observed as stress-strain data at a series of time points. The first stage of the experimental work involves the characterization of the isothermal physical aging behavior of two advanced thermoplastics. The second stage conducts tests on the same materials with varying thermal histories and with long-term test duration. This forms the basis to assess and modify a nonisothermal physical aging model (KAHR-ate model). Based on the experimental findings, the KAHR-ate model has been revised by new correlations between aging shift factors and volume response; this revised model performed well in predicting the nonisothermal physical aging behavior of glassy polymers. In the work on isothermal physical aging, short-term creep and stress relaxation tests were performed at several temperatures within 15-35°C below the glass transition temperature (Tg) at various aging times, using the short-term test method established by Struik. Stress and strain levels were such that the materials remained in the linear viscoelastic regime. These curves were then shifted together to determine momentary master curves and shift rates. In order to validate the obtained isothermal physical aging behavior, the results of creep and stress relaxation testing were compared and shown to be consistent with one another using appropriate interconversion of the viscoelastic material functions. Time-temperature superposition of the master curves was also performed. The temperature shift factors and aging shift rates for both PEEK and PPS were consistent for both creep and stress relaxation test results. Nonisothermal physical aging was monitored by sequential short-term creep tests after a series of temperature jumps; the resulting strain histories were analyzed to determine aging shift factors (ate) for each of the creep tests. The nonisothermal aging response was predicted using the KAHR-ate model, which combines the KAHR model of volume recovery with a suitable linear relationship between aging shift factors and specific volume. The KAHR-ate model can be utilized to both predict aging response and to determine necessary model parameters from a set of aging shift factor data. For the PEEK and PPS materials considered in the current study, predictions of mechanical response were demonstrated to be in good agreement with the experimental results for several complicated thermal histories. In addition to short-term nonisothermal aging, long-term creep tests under identical thermal conditions were also analyzed. Effective time theory was unitized to predict long-term response under both isothermal and nonisothermal temperature histories. The long-term compliance after a series of temperature changes was predicted by the KAHR- ate model, and the theoretical predictions and experimental data showed good agreement for various thermal histories. Lastly, physical aging behavior of PPS near the glass transition temperature was investigated, in order to observe the mechanical response in the process of the evolution of the material into equilibrium. At several temperatures near Tg, the time need to reach equilibrium were determined by the creep test results at various aging times. In addition to isothermal physical aging, mechanical shift factors in the period of approaching equilibrium at a common temperature after temperature up-jumps and down-jumps are monitored from creep tests; prior to these temperature jumps, the materials were aged to reach equilibrium states. From these tests, asymmetry of approaching equilibrium phenomenon in ate was observed, which is first-time reported in the literature. This finding shows the similarity between the thermodynamic and mechanical properties during structural relaxation. This work will lead to improved understanding of the viscoelastic behavior of glassy polymers, which is important for better understanding and design of PMCs in elevated temperature applications. With the above findings, this dissertation deals with nonisothermal physical aging of glassy polymers, including both experimental characterization and constructing a framework for predictions of mechanical behavior of polymeric materials under complicated thermal conditions. (Abstract shortened by UMI.)
Long-term trends in fire behavior and changes in population at risk
Long-term trends in fire behavior and changes in population at risk Rappold AG, Peterson GC, US EPA Matt Jolly, USFS Air pollution regulations and technological advances have successfully reduced emissions of air pollutants from many anthropogenic sources in recent decades. Duri...
Berger, Theodore W.; Song, Dong; Chan, Rosa H. M.; Marmarelis, Vasilis Z.; LaCoss, Jeff; Wills, Jack; Hampson, Robert E.; Deadwyler, Sam A.; Granacki, John J.
2012-01-01
This paper describes the development of a cognitive prosthesis designed to restore the ability to form new long-term memories typically lost after damage to the hippocampus. The animal model used is delayed nonmatch-to-sample (DNMS) behavior in the rat, and the “core” of the prosthesis is a biomimetic multi-input/multi-output (MIMO) nonlinear model that provides the capability for predicting spatio-temporal spike train output of hippocampus (CA1) based on spatio-temporal spike train inputs recorded presynaptically to CA1 (e.g., CA3). We demonstrate the capability of the MIMO model for highly accurate predictions of CA1 coded memories that can be made on a single-trial basis and in real-time. When hippocampal CA1 function is blocked and long-term memory formation is lost, successful DNMS behavior also is abolished. However, when MIMO model predictions are used to reinstate CA1 memory-related activity by driving spatio-temporal electrical stimulation of hippocampal output to mimic the patterns of activity observed in control conditions, successful DNMS behavior is restored. We also outline the design in very-large-scale integration for a hardware implementation of a 16-input, 16-output MIMO model, along with spike sorting, amplification, and other functions necessary for a total system, when coupled together with electrode arrays to record extracellularly from populations of hippocampal neurons, that can serve as a cognitive prosthesis in behaving animals. PMID:22438335
Dunkel, Curtis S; Mathes, Eugene
2011-12-16
The role of the individual difference variables of mate value, short-term and long-term mating preferences, and life history strategy along with the manipulated variable of life expectancy were used to predict differences in the willingness to engage in sexually coercive behaviors. Short-term preferences and long-term preferences were correlated with the willingness to engage in sexual coercion at all life expectancies. Life history strategy was correlated with the willingness to engage in sexual coercion at only the shortest and longest life expectancies. Most importantly short-term and long-term mating preferences interacted with life expectancy to predict the willingness to engage in sexually coercive behaviors. Short life expectancies increased willingness in individuals with high short-term and low long-term preferences. The results are discussed in terms of the varying theories of sexual coercion with emphasis put on a life history approach.
Jen, Wen-Yuan; Hung, Ming-Chien
2010-01-01
In an aging society, the issue of increased medical costs troubles both government agencies and families with aging parents. Many elderly people require long-term care, and the medical and financial problems associated with long-term care worry their entire family. Mobile healthcare service (MHS) has been widely applied by medical practitioners and researchers for years. Unfortunately, the elderly often fear both the technology and the cost its use incurs; hence, they seldom actively adopt MHS without the prompting and support of other family members. This study highlights this issue of long-term healthcare for the elderly and extracts the factors affecting their family's intentions in adopting MHS. Based on the integration of the Theory of Planned Behavior and the Technology Acceptance Model, the factors associated with the family's intention of the aging people toward MHS are explored. Data were collected from 200 students in the "Job Master" track in a local "Executive Master of Business Administration" program. Half of them had at least one immediate family member who was older than 65 years of age. A partial least squares (PLS) analysis shows that "attitude" significantly affected the behavioral intention of adopting MHS, and "perceived usefulness" and "perceived ease-of-use" had an indirect effect via "attitude." The PLS model explains the variance in intention (64.1%), attitude (58.1%), and perceived usefulness (33.8%). Overall, this study shows that attitude was an important determinant of MHS adoption. Gender also significantly affected the relationship between attitude and behavioral intention to adopt MHS.
Do Project Pedagogies Make a Difference?
ERIC Educational Resources Information Center
Simeone, James; Shaw, Greg M.
2017-01-01
Community-based action research (CBAR) encourages students to view internships and other civic-engagement opportunities as the first steps in collaborative projects that build long-term relationships with community partners and model how democracy works. We marshal longitudinal data, qualitative and quantitative, on both attitudes and behaviors to…
Choi, Catherine H; Schoenfeld, Brian P; Bell, Aaron J; Hinchey, Joseph; Rosenfelt, Cory; Gertner, Michael J; Campbell, Sean R; Emerson, Danielle; Hinchey, Paul; Kollaros, Maria; Ferrick, Neal J; Chambers, Daniel B; Langer, Steven; Sust, Steven; Malik, Aatika; Terlizzi, Allison M; Liebelt, David A; Ferreiro, David; Sharma, Ali; Koenigsberg, Eric; Choi, Richard J; Louneva, Natalia; Arnold, Steven E; Featherstone, Robert E; Siegel, Steven J; Zukin, R Suzanne; McDonald, Thomas V; Bolduc, Francois V; Jongens, Thomas A; McBride, Sean M J
2016-01-01
Fragile X is the most common monogenic disorder associated with intellectual disability (ID) and autism spectrum disorders (ASD). Additionally, many patients are afflicted with executive dysfunction, ADHD, seizure disorder and sleep disturbances. Fragile X is caused by loss of FMRP expression, which is encoded by the FMR1 gene. Both the fly and mouse models of fragile X are also based on having no functional protein expression of their respective FMR1 homologs. The fly model displays well defined cognitive impairments and structural brain defects and the mouse model, although having subtle behavioral defects, has robust electrophysiological phenotypes and provides a tool to do extensive biochemical analysis of select brain regions. Decreased cAMP signaling has been observed in samples from the fly and mouse models of fragile X as well as in samples derived from human patients. Indeed, we have previously demonstrated that strategies that increase cAMP signaling can rescue short term memory in the fly model and restore DHPG induced mGluR mediated long term depression (LTD) in the hippocampus to proper levels in the mouse model (McBride et al., 2005; Choi et al., 2011, 2015). Here, we demonstrate that the same three strategies used previously with the potential to be used clinically, lithium treatment, PDE-4 inhibitor treatment or mGluR antagonist treatment can rescue long term memory in the fly model and alter the cAMP signaling pathway in the hippocampus of the mouse model.
Rapid Associative Learning and Stable Long-Term Memory in the Squid Euprymna scolopes.
Zepeda, Emily A; Veline, Robert J; Crook, Robyn J
2017-06-01
Learning and memory in cephalopod molluscs have received intensive study because of cephalopods' complex behavioral repertoire and relatively accessible nervous systems. While most of this research has been conducted using octopus and cuttlefish species, there has been relatively little work on squid. Euprymna scolopes Berry, 1913, a sepiolid squid, is a promising model for further exploration of cephalopod cognition. These small squid have been studied in detail for their symbiotic relationship with bioluminescent bacteria, and their short generation time and successful captive breeding through multiple generations make them appealing models for neurobiological research. However, little is known about their behavior or cognitive ability. Using the well-established "prawn-in-the-tube" assay of learning and memory, we show that within a single 10-min trial E. scolopes learns to inhibit its predatory behavior, and after three trials it can retain this memory for at least 12 d. Rapid learning and very long-term retention were apparent under two different training schedules. To our knowledge, this study is the first demonstration of learning and memory in this species as well as the first demonstration of associative learning in any squid.
Rothstein, Jessica D; Leontsini, Elli; Olortegui, Maribel Paredes; Yori, Pablo Peñataro; Surkan, Pamela J; Kosek, Margaret
2015-09-01
The gap between the efficacy and the effectiveness of household water treatment in reducing diarrhea-related morbidity indicates the need for a better understanding of the determinants of long-term behavior change. To explore the barriers to drinking water chlorination in the Peruvian Amazon, where diarrhea is endemic among under-5 children, we conducted qualitative research with 23 caregivers from peri-urban communities of Iquitos, Peru. Our inquiry drew on the Transtheoretical Model of behavior change and the Integrated Behavioral Model for Water, Sanitation, and Hygiene to identify the most relevant contextual, psychosocial, and technological determinants of initial action and long-term adoption of chlorination. Our findings suggest that the decision to try out this practice resulted from the combined effect of knowledge of chlorination benefits and product availability and affordability. Progress from action to adoption was influenced by caretakers' understanding of dosage, the packaging of chlorine products, knowledge and skills for multipurpose laundry bleach, the taste of treated water, and reinforcement. This analysis suggests that a focus on these determinants and the household domain may help to improve the sustainability of future intervention efforts. © The American Society of Tropical Medicine and Hygiene.
Rothstein, Jessica D.; Leontsini, Elli; Olortegui, Maribel Paredes; Yori, Pablo Peñataro; Surkan, Pamela J.; Kosek, Margaret
2015-01-01
The gap between the efficacy and the effectiveness of household water treatment in reducing diarrhea-related morbidity indicates the need for a better understanding of the determinants of long-term behavior change. To explore the barriers to drinking water chlorination in the Peruvian Amazon, where diarrhea is endemic among under-5 children, we conducted qualitative research with 23 caregivers from peri-urban communities of Iquitos, Peru. Our inquiry drew on the Transtheoretical Model of behavior change and the Integrated Behavioral Model for Water, Sanitation, and Hygiene to identify the most relevant contextual, psychosocial, and technological determinants of initial action and long-term adoption of chlorination. Our findings suggest that the decision to try out this practice resulted from the combined effect of knowledge of chlorination benefits and product availability and affordability. Progress from action to adoption was influenced by caretakers' understanding of dosage, the packaging of chlorine products, knowledge and skills for multipurpose laundry bleach, the taste of treated water, and reinforcement. This analysis suggests that a focus on these determinants and the household domain may help to improve the sustainability of future intervention efforts. PMID:26175028
Hu, Ruofei; Cancela, Jorge; Cea, Gloria; Vlachopapadopoulou, Elpis-Athina; Fotiadis, Dimitrios I.; Fico, Giuseppe
2016-01-01
Childhood obesity is becoming one of the 21st century’s most important public health problems. Nowadays, the main treatment of childhood obesity is behavior intervention that aims at improve children’s lifestyle to arrest the disease. Information and communication technologies (ICTs) have not been widely employed in this intervention, and most of existing ICTs systems are not having a long-term effect. The purpose of this paper is to define a system to support family-based intervention through a state-of-the-art analysis of family-based interventions and related technological solutions first, and then using the analytic hierarchy process to derive a childhood obesity family-based behavior intervention model, and finally to provide a prototype of a system called OB CITY. The system makes use of applied behavior analysis, affective computing technologies, as well as serious game and gamification techniques, to offer long term services in all care dimensions of the family-based behavioral intervention aiming to provide positive effects to the treatment of childhood obesity. PMID:27602306
Video games and aggressive thoughts, feelings, and behavior in the laboratory and in life.
Anderson, C A; Dill, K E
2000-04-01
Two studies examined violent video game effects on aggression-related variables. Study 1 found that real-life violent video game play was positively related to aggressive behavior and delinquency. The relation was stronger for individuals who are characteristically aggressive and for men. Academic achievement was negatively related to overall amount of time spent playing video games. In Study 2, laboratory exposure to a graphically violent video game increased aggressive thoughts and behavior. In both studies, men had a more hostile view of the world than did women. The results from both studies are consistent with the General Affective Aggression Model, which predicts that exposure to violent video games will increase aggressive behavior in both the short term (e.g., laboratory aggression) and the long term (e.g., delinquency).
Cryan, John F; Page, Michelle E; Lucki, Irwin
2005-11-01
The forced swim test (FST) is the most widely used model for assessing potential antidepressant activity in rodents following acute or short-term treatment. However, few studies have compared the effects of short- and long-term antidepressant treatment on behaviors in the test, despite the need to treat patients chronically to produce clinical effects. The current studies examined whether antidepressants from different classes produce different behavioral effects following short-term treatment and whether such effects change following administration for a longer duration. The effects of administering short-term (3 days) and long-term (14 days) treatments of antidepressants from three different chemical classes with distinct mechanisms of action via osmotic minipump were examined: the selective norepinephrine reuptake inhibitor reboxetine (10 and 60 mg kg(-1) day(-1)), the selective serotonin reuptake inhibitor fluoxetine (2.5 and 15 mg kg(-1) day(-1)), and the reversible inhibitor of monoamine oxidase moclobemide (2.5 and 15 mg kg(-1) day(-1)). All testing was carried out in a 15-min test with no preswim session in order to negate any confounding aspect of an induction procedure. The majority of antidepressant-sensitive behavioral changes were observed in the first 5 min of the test. The low dose of reboxetine failed to alter behavior in the test after 3 days but significantly decreased immobility and increased climbing behavior following administration for 14 days, whereas the high dose of reboxetine was equally effective following 3 and 14 days of treatment. In a similar fashion, the low dose of fluoxetine failed to alter behavior in the test following 3 days, but showed an augmented response on immobility and increased swimming following administration for 14 days. The high dose of fluoxetine was slightly more effective at reducing immobility following administration for 14 days than 3 days. The low dose of moclobemide decreased immobility and increased climbing behavior following treatment for 3 days, but increases in both swimming and climbing behaviors were measured following treatment for 14 days. Treatment with the high dose of moclobemide for 3 days decreased immobility and increased swimming, whereas treatment for 14 days significantly increased both active behaviors (swimming and climbing). Antidepressants from three different classes produce different effects on active behaviors in the FST. The effects of antidepressants were augmented following chronic administration for 14 days, especially when given at low doses. This suggests that modifications of the FST can be used to examine the onset of action of antidepressant agents produced by long-term administration.
How Do You Motivate Long-Term Behavior Change to Prevent Cancer?
John P. Pierce PhD, a professor in the Department of Family and Preventive Medicine at the University of California, San Diego and Director of Population Science at Moores Cancer Center, presented "How Do You Motivate Long-Term Behavior Change to Prevent Cancer?"
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lavergne, F.; Sab, K., E-mail: karam.sab@enpc.fr; Sanahuja, J.
2015-05-15
Prestress losses due to creep of concrete is a matter of interest for long-term operations of nuclear power plants containment buildings. Experimental studies by Granger (1995) have shown that concretes with similar formulations have different creep behaviors. The aim of this paper is to numerically investigate the effect of size distribution and shape of elastic inclusions on the long-term creep of concrete. Several microstructures with prescribed size distribution and spherical or polyhedral shape of inclusions are generated. By using the 3D numerical homogenization procedure for viscoelastic microstructures proposed by Šmilauer and Bažant (2010), it is shown that the size distributionmore » and shape of inclusions have no measurable influence on the overall creep behavior. Moreover, a mean-field estimate provides close predictions. An Interfacial Transition Zone was introduced according to the model of Nadeau (2003). It is shown that this feature of concrete's microstructure can explain differences between creep behaviors.« less
Robitaille, Annie; Garcia, Linda; McIntosh, Cameron
2015-09-01
The current study examines the longitudinal relationship between dementia-related challenging behaviors (e.g., vocal disruption, physical aggression, repetitive behaviors, and restlessness) and cognitive functioning in the long-term care (LTC) context. A multivariate latent growth curve model within the structural equation modeling (SEM) framework was applied to data collected from 16,804 older adults upon admission to LTC and every 3 months for a period of 2.5 years. Increases in challenging behaviors were characterized by a significant positive linear and negative quadratic trend (i.e., a subtle leveling off at later assessment times), whereas increases in cognitive impairment were characterized by a positive linear trend. On average, individuals who were more cognitively impaired upon entry into LTC and who exhibited a steeper increase in cognitive impairment also exhibited more challenging behaviors at entry into LTC and a steeper increase in challenging behaviors, respectively. At the within-person level, individuals demonstrating an increase in cognitive impairment at a specific occasion were also more likely to demonstrate an increase in challenging behaviors at that same occasion; however, the magnitude of these effects was very small, suggesting limited practical implications. This study provides novel empirical evidence about the coevolution of cognitive impairment and challenging behaviors, going beyond prior research that has been either cross-sectional in nature, examined longitudinal change in only 1 variable, or simply looked at linear trends without attempting to explore the possibility of nonlinear change. Most importantly, this longitudinal examination of persons with dementia living in LTC has implications for how challenging behaviors can be better managed and for how new strategies can be implemented to prevent challenging behaviors. (c) 2015 APA, all rights reserved).
Restricted vs. unrestricted wheel running in mice: Effects on brain, behavior and endocannabinoids.
Biedermann, Sarah V; Auer, Matthias K; Bindila, Laura; Ende, Gabriele; Lutz, Beat; Weber-Fahr, Wolfgang; Gass, Peter; Fuss, Johannes
2016-11-01
Beneficial effects of voluntary wheel running on hippocampal neurogenesis, morphology and hippocampal-dependent behavior have widely been studied in rodents, but also serious side effects and similarities to stereotypy have been reported. Some mouse strains run excessively when equipped with running wheels, complicating the comparability to human exercise regimes. Here, we investigated how exercise restriction to 6h/day affects hippocampal morphology and metabolism, stereotypic and basal behaviors, as well as the endocannabinoid system in wheel running C57BL/6 mice; the strain most commonly used for behavioral analyses and psychiatric disease models. Restricted and unrestricted wheel running had similar effects on immature hippocampal neuron numbers, thermoregulatory nest building and basal home-cage behaviors. Surprisingly, hippocampal gray matter volume, assessed with magnetic resonance (MR) imaging at 9.4 Tesla, was only increased in unrestricted but not in restricted runners. Moreover, unrestricted runners showed less stereotypic behavior than restricted runners did. However, after blockage of running wheels for 24h stereotypic behavior also increased in unrestricted runners, arguing against a long-term effect of wheel running on stereotypic behavior. Stereotypic behaviors correlated with frontal glutamate and glucose levels assessed by 1 H-MR spectroscopy. While acute running increased plasma levels of the endocannabinoid anandamide in former studies in mice and humans, we found an inverse correlation of anandamide with the daily running distance after long-term running. In conclusion, although there are some diverging effects of restricted and unrestricted running on brain and behavior, restricted running does not per se seem to be a better animal model for aerobic exercise in mice. Copyright © 2016 Elsevier Inc. All rights reserved.
Stationarity: Wanted dead or alive?
Lins, Larry F.; Cohn, Timothy A.
2011-01-01
Aligning engineering practice with natural process behavior would appear, on its face, to be a prudent and reasonable course of action. However, if we do not understand the long-term characteristics of hydroclimatic processes, how does one find the prudent and reasonable course needed for water management? We consider this question in light of three aspects of existing and unresolved issues affecting hydroclimatic variability and statistical inference: Hurst-Kolmogorov phenomena; the complications long-term persistence introduces with respect to statistical understanding; and the dependence of process understanding on arbitrary sampling choices. These problems are not easily addressed. In such circumstances, humility may be more important than physics; a simple model with well-understood flaws may be preferable to a sophisticated model whose correspondence to reality is uncertain.
Uttl, Libor; Petrasek, Tomas; Sengul, Hilal; Svojanovska, Marketa; Lobellova, Veronika; Vales, Karel; Radostova, Dominika; Tsenov, Grygoriy; Kubova, Hana; Mikulecka, Anna; Svoboda, Jan; Stuchlik, Ales
2018-01-01
The role of NMDA receptors in learning, memory and hippocampal function has long been recognized. Post-mortem studies have indicated that the expression or subunit composition of the NMDA glutamate receptor subtype might be related to the impaired cognitive functions found in schizophrenia patients. NMDA receptor antagonists have been used to develop animal models of this disorder. There is accumulating evidence showing that not only the acute but also the chronic application of NMDA receptor antagonists may induce schizophrenia-like alterations in behavior and brain functions. However, limited evidence is available regarding the consequences of NMDA receptor blockage during periods of adolescence and early adulthood. This study tested the hypothesis that a 2-week treatment of male Long-Evans and Wistar rats with dizocilpine (MK-801; 0.5 mg/kg daily) starting at postnatal days (PD) 30 and 60 would cause a long-term cognitive deficit and changes in the levels of NMDA receptor subunits. The working memory version of the Morris water maze (MWM) and active place avoidance with reversal on a rotating arena (Carousel) requiring cognitive coordination and flexibility probed cognitive functions and an elevated-plus maze (EPM) was used to measure anxiety-like behavior. The western blot method was used to determine changes in NMDA receptor subunit levels in the hippocampus. Our results showed no significant changes in behaviors in Wistar rats. Slightly elevated anxiety-like behavior was observed in the EPM in Long-Evans rats with the onset of treatment on PD 30. Furthermore, Long-Evans rats treated from PD 60 displayed impaired working memory in the MWM. There were; however, no significant changes in the levels of NMDA receptor subunits because of MK-801 administration. These findings suggest that a 2-week treatment starting on PD 60 in Long-Evans rats leads to long-term changes in working memory, but this deficit is not paralleled by changes in NMDA receptor subunits. These results support the face validity, but not construct validity of this model. We suggest that chronic treatment of adolescent and adult rats does not constitute a plausible animal model of schizophrenia. PMID:29487522
Uttl, Libor; Petrasek, Tomas; Sengul, Hilal; Svojanovska, Marketa; Lobellova, Veronika; Vales, Karel; Radostova, Dominika; Tsenov, Grygoriy; Kubova, Hana; Mikulecka, Anna; Svoboda, Jan; Stuchlik, Ales
2018-01-01
The role of NMDA receptors in learning, memory and hippocampal function has long been recognized. Post-mortem studies have indicated that the expression or subunit composition of the NMDA glutamate receptor subtype might be related to the impaired cognitive functions found in schizophrenia patients. NMDA receptor antagonists have been used to develop animal models of this disorder. There is accumulating evidence showing that not only the acute but also the chronic application of NMDA receptor antagonists may induce schizophrenia-like alterations in behavior and brain functions. However, limited evidence is available regarding the consequences of NMDA receptor blockage during periods of adolescence and early adulthood. This study tested the hypothesis that a 2-week treatment of male Long-Evans and Wistar rats with dizocilpine (MK-801; 0.5 mg/kg daily) starting at postnatal days (PD) 30 and 60 would cause a long-term cognitive deficit and changes in the levels of NMDA receptor subunits. The working memory version of the Morris water maze (MWM) and active place avoidance with reversal on a rotating arena (Carousel) requiring cognitive coordination and flexibility probed cognitive functions and an elevated-plus maze (EPM) was used to measure anxiety-like behavior. The western blot method was used to determine changes in NMDA receptor subunit levels in the hippocampus. Our results showed no significant changes in behaviors in Wistar rats. Slightly elevated anxiety-like behavior was observed in the EPM in Long-Evans rats with the onset of treatment on PD 30. Furthermore, Long-Evans rats treated from PD 60 displayed impaired working memory in the MWM. There were; however, no significant changes in the levels of NMDA receptor subunits because of MK-801 administration. These findings suggest that a 2-week treatment starting on PD 60 in Long-Evans rats leads to long-term changes in working memory, but this deficit is not paralleled by changes in NMDA receptor subunits. These results support the face validity, but not construct validity of this model. We suggest that chronic treatment of adolescent and adult rats does not constitute a plausible animal model of schizophrenia.
Arrogi, Anass; Schotte, Astrid; Bogaerts, An; Boen, Filip; Seghers, Jan
2017-01-09
The objective of the present study was to evaluate the short- and long-term intervention and mediation effects of a 3-month individualized need-supportive physical activity (PA) counseling intervention on employees' PA and sedentary behavior. Insufficiently active employees (n = 300; mean age 42 ± 9 years; 78% female) were recruited from a large pharmaceutical company in Flanders, Belgium. A quasi-experimental design was used in which the intervention group (N = 246) was recruited separately from the reference group (N = 54). Intervention group participants received a 3-month behavioral support intervention, which consisted of two one-hour face-to-face counseling sessions and three follow-up counseling contacts by e-mail or telephone at weeks three, six and nine. PA counseling, delivered by qualified PA counselors, aimed to satisfy participants' basic psychological needs for autonomy, competence, and relatedness. Reference group participants did not receive individualized PA counseling. Outcome measures included objectively assessed and self-reported PA and sedentary time and psychological need satisfaction. Assessments were held at baseline, immediately after the intervention (short-term) and 6 months post-intervention (long-term). Mixed model analyses and bootstrapping analyses were used to determine intervention and mediation effects, respectively. The intervention group increased weekday daily steps both in the short- and long-term, while the reference group showed reductions in daily step count (ES = .65 and ES = .48 in the short- and long-term, respectively). In the short-term, weekday moderate-to-vigorous PA increased more pronouncedly in the intervention group compared to the reference group (ES = .34). Moreover, the intervention group demonstrated reductions in self-reported sitting time during weekends both in the short- and long-term, whereas the reference group reported increased sitting time (ES = .44 and ES = .32 in the short- and long-term, respectively). Changes in perceived autonomy and competence need satisfaction mediated the long-term intervention effects on daily step count. A 3-month individualized need-supportive PA counseling intervention among employees resulted in significant and sustained improvements in weekday daily step count and in decreased self-reported sitting during weekends. Our findings contribute to the growing evidence of the long-term effectiveness of need-supportive PA counseling. ClinicalTrials.gov NCT01759927 . Registered December 30, 2012.
Evolutionary dynamics of social dilemmas in structured heterogeneous populations.
Santos, F C; Pacheco, J M; Lenaerts, Tom
2006-02-28
Real populations have been shown to be heterogeneous, in which some individuals have many more contacts than others. This fact contrasts with the traditional homogeneous setting used in studies of evolutionary game dynamics. We incorporate heterogeneity in the population by studying games on graphs, in which the variability in connectivity ranges from single-scale graphs, for which heterogeneity is small and associated degree distributions exhibit a Gaussian tale, to scale-free graphs, for which heterogeneity is large with degree distributions exhibiting a power-law behavior. We study the evolution of cooperation, modeled in terms of the most popular dilemmas of cooperation. We show that, for all dilemmas, increasing heterogeneity favors the emergence of cooperation, such that long-term cooperative behavior easily resists short-term noncooperative behavior. Moreover, we show how cooperation depends on the intricate ties between individuals in scale-free populations.
The Mars water cycle at other epochs: History of the polar caps and layered terrain
NASA Technical Reports Server (NTRS)
Jakosky, Bruce M.; Henderson, Bradley G.; Mellon, Michael T.
1992-01-01
The atmospheric water cycle at the present epoch involves summertime sublimation of water from the north polar cap, transport of water through the atmosphere, and condensation on one or both winter CO2 caps. Exchange with the regolith is important seasonally, but the water content of the atmosphere appears to be controlled by the polar caps. The net annual transport through the atmosphere, integrated over long timescales, must be the driving force behind the long-term evolution of the polar caps; clearly, this feeds back into the evolution of the layered terrain. We have investigated the behavior of the seasonal water cycle and the net integrated behavior at the pole for the last 10 exp 7 years. Our model of the water cycle includes the solar input, CO2 condensation and sublimation, and summertime water sublimation through the seasonal cycles, and incorporates the long-term variations in the orbital elements describing the Martian orbit.
The benefits of cholinergic enhancement during perceptual learning are long-lasting
Rokem, Ariel; Silver, Michael A.
2013-01-01
The neurotransmitter acetylcholine (ACh) regulates many aspects of cognition, including attention and memory. Previous research in animal models has shown that plasticity in sensory systems often depends on the behavioral relevance of a stimulus and/or task. However, experimentally increasing ACh release in the cortex can result in experience-dependent plasticity, even in the absence of behavioral relevance. In humans, the pharmacological enhancement of ACh transmission by administration of the cholinesterase inhibitor donepezil during performance of a perceptual task increases the magnitude of perceptual learning (PL) and its specificity to physical parameters of the stimuli used for training. Behavioral effects of PL have previously been shown to persist for many months. In the present study, we tested whether enhancement of PL by donepezil is also long-lasting. Healthy human subjects were trained on a motion direction discrimination task during cholinergic enhancement, and follow-up testing was performed 5–15 months after the end of training and without additional drug administration. Increases in performance associated with training under donepezil were evident in follow-up retesting, indicating that cholinergic enhancement has beneficial long-term effects on PL. These findings suggest that cholinergic enhancement of training procedures used to treat clinical disorders should improve long-term outcomes of these procedures. PMID:23755006
Long-Term Habituation of the C-Start Escape Response in Zebrafish Larvae
Roberts, Adam C.; Pearce, Kaycey C.; Choe, Ronny C.; Alzagatiti, Joseph B.; Yeung, Anthony K.; Bill, Brent R.; Glanzman, David L.
2016-01-01
The cellular and molecular basis of long-term memory in vertebrates remains poorly understood. Knowledge regarding long-term memory has been impeded by the enormous complexity of the vertebrate brain, particularly the mammalian brain, as well as by the relative complexity of the behavioral alterations examined in most studies of long-term memory in vertebrates. Here, we demonstrate a long-term form of nonassociative learning—specifically, long-term habituation (LTH)—of a simple reflexive escape response, the C-start, in zebrafish larvae. The C-start is triggered by the activation of one of a pair of giant neurons in the zebrafish’s hindbrain, the Mauthner cells. We show that LTH of the C-start requires the activity of NMDA receptors and involves macromolecular synthesis. We further show that the long-term habituated reflex can by rapidly dishabituated by a brief tactile stimulus. Our results set the stage for rigorous, mechanistic investigations of the long-term memory for habituation of a reflexive behavioral response, one that is mediated by a relatively simple, neurobiologically tractable, neural circuit. Moreover, the demonstration of NMDAR and transcriptionally dependent LTH in a translucent vertebrate organism should facilitate the use of optical recording, and optogenetic manipulation, of neuronal activity to elucidate the cellular basis of a long-term vertebrate memory. PMID:27555232
Analysis of a dynamic model of guard cell signaling reveals the stability of signal propagation
NASA Astrophysics Data System (ADS)
Gan, Xiao; Albert, RéKa
Analyzing the long-term behaviors (attractors) of dynamic models of biological systems can provide valuable insight into biological phenotypes and their stability. We identified the long-term behaviors of a multi-level, 70-node discrete dynamic model of the stomatal opening process in plants. We reduce the model's huge state space by reducing unregulated nodes and simple mediator nodes, and by simplifying the regulatory functions of selected nodes while keeping the model consistent with experimental observations. We perform attractor analysis on the resulting 32-node reduced model by two methods: 1. converting it into a Boolean model, then applying two attractor-finding algorithms; 2. theoretical analysis of the regulatory functions. We conclude that all nodes except two in the reduced model have a single attractor; and only two nodes can admit oscillations. The multistability or oscillations do not affect the stomatal opening level in any situation. This conclusion applies to the original model as well in all the biologically meaningful cases. We further demonstrate the robustness of signal propagation by showing that a large percentage of single-node knockouts does not affect the stomatal opening level. Thus, we conclude that the complex structure of this signal transduction network provides multiple information propagation pathways while not allowing extensive multistability or oscillations, resulting in robust signal propagation. Our innovative combination of methods offers a promising way to analyze multi-level models.
Holcman, A; Gorjanc, G; Stuhec, I
2008-09-01
The purpose of this study was to consider the influence of simple and cheap environmental enrichment such as porous concrete on the behavior of laying hens in conventional cages. Forty brown laying hens were housed in individual wire mesh cages: 20 in experimental cages with porous concrete block provided for pecking and 20 in a control group without concrete block provided. Porous concrete block (5 cm length x 5 cm width x 5 cm height) was mounted on the side wall at the height of the hen's head. Behavior was studied from 42 to 48 wk of age. A group of 8 hens was filmed for 24 h, and the camera was moved each day so that all 40 hens were recorded over 5 d each wk. Videotaping was performed in wk 1, 3, 5, and 7 of the experiment. States (long-term behavior) were observed with 5-min interval recording (feeding, preening, resting, and remaining inactive), whereas events (short-term activities) were observed with instantaneous recording (drinking, pecking concrete, pecking neighbors, pecking cage, and attempting to escape). Data were analyzed with generalized linear mixed model with binomial distribution for states, and Poisson distribution for events. Monte Carlo Markov Chain methods were used to estimate model parameters. Because posterior distributions of quantities of interest were skewed, medians and standard errors are reported. Hens in experimental cages were more active in long-term behavior than controls (64.9 +/- 1.9 and 59.3 +/- 1.9% of the light period, respectively). Correspondingly, hens in the control group showed more long-term inactivity. In addition to pecking the porous concrete block, hens in experimental cages also showed other short-term activities with greater frequency (4.10 +/- 0.31 and 3.51 +/- 0.25 events per h, respectively). Our hypothesis that hens in enriched cages would have a greater level of activity was confirmed. Provision of a piece of porous concrete block as a pecking substrate enriched the environment of the birds at negligible cost.
2015-01-01
Computational simulations are currently used to identify epidemic dynamics, to test potential prevention and intervention strategies, and to study the effects of social behaviors on HIV transmission. The author describes an agent-based epidemic simulation model of a network of individuals who participate in high-risk sexual practices, using number of partners, condom usage, and relationship length to distinguish between high- and low-risk populations. Two new concepts—free links and fixed links—are used to indicate tendencies among individuals who either have large numbers of short-term partners or stay in long-term monogamous relationships. An attempt was made to reproduce epidemic curves of reported HIV cases among male homosexuals in Taiwan prior to using the agent-based model to determine the effects of various policies on epidemic dynamics. Results suggest that when suitable adjustments are made based on available social survey statistics, the model accurately simulates real-world behaviors on a large scale. PMID:25815047
Impact of long-term care insurance on institutional dementia care in Japan.
Ito, Hiroto; Miyamoto, Yuki
2003-06-01
Japan started long-term care insurance for nursing and home help services in April 2000 to cope with growing medical expenditures for the population aged over 65. To study the impact of the new insurance on utilization of dementia care, we compared demographic and clinical characteristics including diagnosis, degree of disability and behavioral disturbance before and after the launch among people with dementia covered by either long-term care or medical insurance. The subjects of the study were randomly selected patients/residents of specialized dementia care units in both psychiatric hospitals and geriatric care facilities before (1145 patients/residents in early 2000) and after (262 for medical insurance and 205 for long-term care insurance in 2001) the new system was launched. Although patients/residents in 2000 and 2001 were similar as a whole, the 2001 sample showed differences between patients in each of the types of insurance systems. Logistic regression analysis revealed that patients/residents covered by long-term care insurance were significantly more likely to be females and require higher levels of care. Patients covered by long-term care insurance were significantly less likely to be transferred from a psychiatric department nor did they display behavioral disturbance or an inability to put out or deal with fire. These results suggest that health care facilities have shifted to the new insurance system for patients requiring higher levels of care but without behavioral disturbances as it was intended. On the other hand, there were policy concerns of that demented persons with moderate activities of daily living impairments and behavioral disturbances would be at risk being excluded from the long-term care scheme.
Modeling Collective Animal Behavior with a Cognitive Perspective: A Methodological Framework
Weitz, Sebastian; Blanco, Stéphane; Fournier, Richard; Gautrais, Jacques; Jost, Christian; Theraulaz, Guy
2012-01-01
The last decades have seen an increasing interest in modeling collective animal behavior. Some studies try to reproduce as accurately as possible the collective dynamics and patterns observed in several animal groups with biologically plausible, individual behavioral rules. The objective is then essentially to demonstrate that the observed collective features may be the result of self-organizing processes involving quite simple individual behaviors. Other studies concentrate on the objective of establishing or enriching links between collective behavior researches and cognitive or physiological ones, which then requires that each individual rule be carefully validated. Here we discuss the methodological consequences of this additional requirement. Using the example of corpse clustering in ants, we first illustrate that it may be impossible to discriminate among alternative individual rules by considering only observational data collected at the group level. Six individual behavioral models are described: They are clearly distinct in terms of individual behaviors, they all reproduce satisfactorily the collective dynamics and distribution patterns observed in experiments, and we show theoretically that it is strictly impossible to discriminate two of these models even in the limit of an infinite amount of data whatever the accuracy level. A set of methodological steps are then listed and discussed as practical ways to partially overcome this problem. They involve complementary experimental protocols specifically designed to address the behavioral rules successively, conserving group-level data for the overall model validation. In this context, we highlight the importance of maintaining a sharp distinction between model enunciation, with explicit references to validated biological concepts, and formal translation of these concepts in terms of quantitative state variables and fittable functional dependences. Illustrative examples are provided of the benefits expected during the often long and difficult process of refining a behavioral model, designing adapted experimental protocols and inversing model parameters. PMID:22761685
Modeling collective animal behavior with a cognitive perspective: a methodological framework.
Weitz, Sebastian; Blanco, Stéphane; Fournier, Richard; Gautrais, Jacques; Jost, Christian; Theraulaz, Guy
2012-01-01
The last decades have seen an increasing interest in modeling collective animal behavior. Some studies try to reproduce as accurately as possible the collective dynamics and patterns observed in several animal groups with biologically plausible, individual behavioral rules. The objective is then essentially to demonstrate that the observed collective features may be the result of self-organizing processes involving quite simple individual behaviors. Other studies concentrate on the objective of establishing or enriching links between collective behavior researches and cognitive or physiological ones, which then requires that each individual rule be carefully validated. Here we discuss the methodological consequences of this additional requirement. Using the example of corpse clustering in ants, we first illustrate that it may be impossible to discriminate among alternative individual rules by considering only observational data collected at the group level. Six individual behavioral models are described: They are clearly distinct in terms of individual behaviors, they all reproduce satisfactorily the collective dynamics and distribution patterns observed in experiments, and we show theoretically that it is strictly impossible to discriminate two of these models even in the limit of an infinite amount of data whatever the accuracy level. A set of methodological steps are then listed and discussed as practical ways to partially overcome this problem. They involve complementary experimental protocols specifically designed to address the behavioral rules successively, conserving group-level data for the overall model validation. In this context, we highlight the importance of maintaining a sharp distinction between model enunciation, with explicit references to validated biological concepts, and formal translation of these concepts in terms of quantitative state variables and fittable functional dependences. Illustrative examples are provided of the benefits expected during the often long and difficult process of refining a behavioral model, designing adapted experimental protocols and inversing model parameters.
Rubinstein, Justin L.; Ellsworth, William L.; Chen, Kate Huihsuan; Uchida, Naoki
2012-01-01
The behavior of individual events in repeating earthquake sequences in California, Taiwan and Japan is better predicted by a model with fixed inter-event time or fixed slip than it is by the time- and slip-predictable models for earthquake occurrence. Given that repeating earthquakes are highly regular in both inter-event time and seismic moment, the time- and slip-predictable models seem ideally suited to explain their behavior. Taken together with evidence from the companion manuscript that shows similar results for laboratory experiments we conclude that the short-term predictions of the time- and slip-predictable models should be rejected in favor of earthquake models that assume either fixed slip or fixed recurrence interval. This implies that the elastic rebound model underlying the time- and slip-predictable models offers no additional value in describing earthquake behavior in an event-to-event sense, but its value in a long-term sense cannot be determined. These models likely fail because they rely on assumptions that oversimplify the earthquake cycle. We note that the time and slip of these events is predicted quite well by fixed slip and fixed recurrence models, so in some sense they are time- and slip-predictable. While fixed recurrence and slip models better predict repeating earthquake behavior than the time- and slip-predictable models, we observe a correlation between slip and the preceding recurrence time for many repeating earthquake sequences in Parkfield, California. This correlation is not found in other regions, and the sequences with the correlative slip-predictable behavior are not distinguishable from nearby earthquake sequences that do not exhibit this behavior.
Long-term oxytocin administration improves social behaviors in a girl with autistic disorder.
Kosaka, Hirotaka; Munesue, Toshio; Ishitobi, Makoto; Asano, Mizuki; Omori, Masao; Sato, Makoto; Tomoda, Akemi; Wada, Yuji
2012-08-13
Patients with autism spectrum disorders (ASDs) exhibit core autistic symptoms including social impairments from early childhood and mostly show secondary disabilities such as irritability and aggressive behavior based on core symptoms. However, there are still no radical treatments of social impairments in these patients. Oxytocin has been reported to play important roles in multiple social behaviors dependent on social recognition, and has been expected as one of the effective treatments of social impairments of patients with ASDs. We present a case of a 16-year-old girl with autistic disorder who treated by long-term administration of oxytocin nasal spray. Her autistic symptoms were successfully treated by two month administration; the girl's social interactions and social communication began to improve without adverse effects. Her irritability and aggressive behavior also improved dramatically with marked decreases in aberrant behavior checklist scores from 69 to 7. This case is the first to illustrate long-term administration of oxytocin nasal spray in the targeted treatment of social impairments in a female with autistic disorder. This case suggests that long-term nasal oxytocin spray is promising and well-tolerated for treatment of social impairments of patients with ASDs.
Long-term oxytocin administration improves social behaviors in a girl with autistic disorder
2012-01-01
Background Patients with autism spectrum disorders (ASDs) exhibit core autistic symptoms including social impairments from early childhood and mostly show secondary disabilities such as irritability and aggressive behavior based on core symptoms. However, there are still no radical treatments of social impairments in these patients. Oxytocin has been reported to play important roles in multiple social behaviors dependent on social recognition, and has been expected as one of the effective treatments of social impairments of patients with ASDs. Case presentation We present a case of a 16-year-old girl with autistic disorder who treated by long-term administration of oxytocin nasal spray. Her autistic symptoms were successfully treated by two month administration; the girl’s social interactions and social communication began to improve without adverse effects. Her irritability and aggressive behavior also improved dramatically with marked decreases in aberrant behavior checklist scores from 69 to 7. Conclusion This case is the first to illustrate long-term administration of oxytocin nasal spray in the targeted treatment of social impairments in a female with autistic disorder. This case suggests that long-term nasal oxytocin spray is promising and well-tolerated for treatment of social impairments of patients with ASDs. PMID:22888794
Case Studies of a Behavior Inclusion Model in an Elementary School District
ERIC Educational Resources Information Center
Santa Cruz, Margaret Escobar
2017-01-01
School discipline practices have traditionally been reactive and punitive in nature. Students violating a school district's code of conduct were often met with exclusionary discipline policies such as out-of-school suspensions, long-term suspensions, and expulsions. Districts attempted to resolve these practices by creating alternative education…
Evolution and Punctuation of Theories of Educational Expenditure and Student Outcomes.
ERIC Educational Resources Information Center
Marion, Russ; Flanigan, Jack
2001-01-01
Examines whether school-expenditure theory can be described in terms of Thomas Kuhn's punctuated-equilibrium model: long periods of theoretical stasis interspersed with brief periods of revolutionary change. Current researchers, influenced by organizational behavior theories, believe that finding a global money/student outcome relationship is an…
Bruining, Hilgo; Matsui, Asuka; Oguro-Ando, Asami; Kahn, René S; Van't Spijker, Heleen M; Akkermans, Guus; Stiedl, Oliver; van Engeland, Herman; Koopmans, Bastijn; van Lith, Hein A; Oppelaar, Hugo; Tieland, Liselotte; Nonkes, Lourens J; Yagi, Takeshi; Kaneko, Ryosuke; Burbach, J Peter H; Yamamoto, Nobuhiko; Kas, Martien J
2015-10-01
Quantitative genetic analysis of basic mouse behaviors is a powerful tool to identify novel genetic phenotypes contributing to neurobehavioral disorders. Here, we analyzed genetic contributions to single-trial, long-term social and nonsocial recognition and subsequently studied the functional impact of an identified candidate gene on behavioral development. Genetic mapping of single-trial social recognition was performed in chromosome substitution strains, a sophisticated tool for detecting quantitative trait loci (QTL) of complex traits. Follow-up occurred by generating and testing knockout (KO) mice of a selected QTL candidate gene. Functional characterization of these mice was performed through behavioral and neurological assessments across developmental stages and analyses of gene expression and brain morphology. Chromosome substitution strain 14 mapping studies revealed an overlapping QTL related to long-term social and object recognition harboring Pcdh9, a cell-adhesion gene previously associated with autism spectrum disorder. Specific long-term social and object recognition deficits were confirmed in homozygous (KO) Pcdh9-deficient mice, while heterozygous mice only showed long-term social recognition impairment. The recognition deficits in KO mice were not associated with alterations in perception, multi-trial discrimination learning, sociability, behavioral flexibility, or fear memory. Rather, KO mice showed additional impairments in sensorimotor development reflected by early touch-evoked biting, rotarod performance, and sensory gating deficits. This profile emerged with structural changes in deep layers of sensory cortices, where Pcdh9 is selectively expressed. This behavior-to-gene study implicates Pcdh9 in cognitive functions required for long-term social and nonsocial recognition. This role is supported by the involvement of Pcdh9 in sensory cortex development and sensorimotor phenotypes. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Mersha, Mahlet D; Patel, Bansri M; Patel, Dipen; Richardson, Brittany N; Dhillon, Harbinder S
2015-09-17
Bisphenol-A (BPA) is a polymerizing agent used in plastic bottles and several routinely used consumer items. It is classified among endocrine disrupting chemicals suspected to cause adverse health effects in mammals ranging from infertility and cancer to behavioral disorders. Work with the invertebrate lab model Caenorhabditis elegans has shown that BPA affects germ cells by disrupting double-stranded DNA break repair mechanisms. The current study utilizes this model organism to provide insight into low-dose and long-term behavioral effects of BPA and bisphenol-S (BPS), a supposed safer replacement for BPA. Experiments presented in our report demonstrate that the effects of embryonic exposure to considerably low levels of BPA persist into adulthood, affecting neural functionality as assayed by measuring habituation to mechano-sensory stimuli in C. elegans. These results are noteworthy in that they are based on low-dose exposures, following the rationale that subtler effects that may not be morphologically apparent are likely to be discernible through behavioral changes. In addition, we report that embryonic exposure to BPS follows a pattern similar to BPA. Building upon previous observations using the C. elegans model, we have shown that exposure of embryos to BPA and BPS affects their behavior as adults. These long-term effects are in line with recommended alternate low-dose chemical safety testing approaches. Our observation that the effects of BPS are similar to BPA is not unexpected, considering their structural similarity. This, to our knowledge, is the first reported behavioral study on low-dose toxicity of any endocrine disrupting chemical in C. elegans.
Acoustic Behavior of North Atlantic Right Whale (Eubalaena glacialis) Mother-Calf Pairs
2013-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Acoustic Behavior of North Atlantic Right Whale ...LONG-TERM GOALS The long-term goal of this project is to quantify the behavior of mother-calf pairs from the North Atlantic right whale ...The primary objectives of this project are to: 1) determine the visual detectability of right whale mother-calf pairs from surface observations
Acoustic Behavior of North Atlantic Right Whale (Eubalaena glacialis) Mother-Calf Pairs
2014-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Acoustic Behavior of North Atlantic Right Whale ...LONG-TERM GOALS The long-term goal of this project is to quantify the behavior of mother-calf pairs from the North Atlantic right whale ...The primary objectives of this project are to: 1) determine the visual detectability of right whale mother-calf pairs from surface observations
Used Fuel Disposal in Crystalline Rocks. FY15 Progress Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yifeng
2015-08-20
The objective of the Crystalline Disposal R&D Work Package is to advance our understanding of long-term disposal of used fuel in crystalline rocks and to develop necessary experimental and computational capabilities to evaluate various disposal concepts in such media. Chapter headings are as follows: Fuel matrix degradation model and its integration with performance assessments, Investigation of thermal effects on the chemical behavior of clays, Investigation of uranium diffusion and retardation in bentonite, Long-term diffusion of U(VI) in bentonite: dependence on density, Sorption and desorption of plutonium by bentonite, Dissolution of plutonium intrinsic colloids in the presence of clay and asmore » a function of temperature, Laboratory investigation of colloid-facilitated transport of cesium by bentonite colloids in a crystalline rock system, Development and demonstration of discrete fracture network model, Fracture continuum model and its comparison with discrete fracture network model.« less
NASA Technical Reports Server (NTRS)
Blaze, Jennifer; Asok, A.; Moyer, E. L.; Roth, T. L.; Ronca, A. E.
2015-01-01
In utero exposure to stress can shape neurobiological and behavioral outcomes in offspring, producing vulnerability to psychopathology later in life. Animal models of prenatal stress likewise have demonstrated long--term alterations in brain function and behavioral deficits in offspring. For example, using a rodent model of unpredictable variable prenatal stress (UVPS), in which dams are exposed to unpredictable, variable stress across pregnancy, we have found increased body weight and anxiety--like behavior in adult male, but not female, offspring. DNA methylation (addition of methyl groups to cytosines which normally represses gene transcription) and changes in telomere length (TTAGGG repeats on the ends of chromosomes) are two molecular modifications that result from stress and could be responsible for the long--term effects of UVPS. Here, we measured methylation of brain--derived neurotrophic factor (bdnf), a gene important in development and plasticity, and telomere length in the brains of adult offspring from the UVPS model. Results indicate that prenatally stressed adult males have greater methylation in the medial prefrontal cortex (mPFC) compared to non--stressed controls, while females have greater methylation in the ventral hippocampus compared to controls. Further, prenatally stressed males had shorter telomeres than controls in the mPFC. These findings demonstrate the ability of UVPS to produce epigenetic alterations and changes in telomere length across behaviorally--relevant brain regions, which may have linkages to the phenotypic outcomes.
Kremer, Kristen P.; Flower, Andrea; Huang, Jin; Vaughn, Michael G.
2016-01-01
The aim of this study was to examine the longitudinal association between externalizing and internalizing behavior and children’s academic achievement, particularly in terms of whether these variables varied as a function of gender and race. Data pertaining to externalizing and internalizing behavior, academic achievement, gender, and race from three waves of the Child Development Supplement of the Panel Study of Income Dynamics (N = 2028) were used. Results indicate that behavior problems had a negative relationship with academic performance and some of these associations endured over time. Externalizing behavior impacted reading scores more negatively for females compared to males at baseline, but the impact of externalizing behavior on long-term reading outcomes did not vary by gender. Externalizing behavior impacted reading scores more negatively for Black children than White children at multiple points in time. Differences between males, females, Black, and White children concerning behavior and achievement are explained. Implications, limitations, and ideas for future research are also presented. PMID:28529397
Behavioral Specifications of Reward-Associated Long-Term Memory Enhancement in Humans
ERIC Educational Resources Information Center
Wittmann, Bianca C.; Dolan, Raymond J.; Duzel, Emrah
2011-01-01
Recent functional imaging studies link reward-related activation of the midbrain substantia nigra-ventral tegmental area (SN/VTA), the site of origin of ascending dopaminergic projections, with improved long-term episodic memory. Here, we investigated in two behavioral experiments how (1) the contingency between item properties and reward, (2) the…
"Old" Habits Die Hard in a Long-Term Care Facility.
ERIC Educational Resources Information Center
VanDomelen, Cindy; And Others
Older Americans are suffering from both physical and social losses as they age. These losses are sometimes accompanied by the elderly person's entrance into a long-term care facility. Some researchers have suggested that such facilities fail to maintain the residents' independent behavior. Others contend that behavior is plastic and can be…
King, Keith A; Vidourek, Rebecca A; Love, Jaime; Wegley, Stacey; Alles-White, Monica
2008-01-01
Unsafe driving and passenger behaviors place teens at increased risk for fatal and nonfatal crashes. This study evaluated the short-and long-term efficacy of the You Hold the Key (YHTK) Teen Driving Countermeasure. A two-page survey was completed by high school students at pretest, posttest, and long-term (6-month) posttest. YHTK was associated with significant immediate and long-term improvements in teen seatbelt use, safe driving, and perceived confidence in preventing drunk driving. Compared to pretests, students at immediate and long-term posttest more frequently wore seatbelts when driving or riding, required passengers to wear seatbelts, and limited the number of passengers to the number of seatbelts in the vehicle. Students were more likely at both posttests to avoid drinking and driving and to say no to riding with a friend who had been drinking. YHTK was associated with increases in safe teen driving and passenger behaviors. Success of YHTK is most notably due to its comprehensive nature. Future programs should consider comprehensive strategies when attempting to modify teen behaviors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Faybishenko, B.; Doughty, C.; Geller, J.
1998-07-01
Understanding subsurface flow and transport processes is critical for effective assessment, decision-making, and remediation activities for contaminated sites. However, for fluid flow and contaminant transport through fractured vadose zones, traditional hydrogeological approaches are often found to be inadequate. In this project, the authors examine flow and transport through a fractured vadose zone as a deterministic chaotic dynamical process, and develop a model of it in these terms. Initially, the authors examine separately the geometric model of fractured rock and the flow dynamics model needed to describe chaotic behavior. Ultimately they will put the geometry and flow dynamics together to developmore » a chaotic-dynamical model of flow and transport in a fractured vadose zone. They investigate water flow and contaminant transport on several scales, ranging from small-scale laboratory experiments in fracture replicas and fractured cores, to field experiments conducted in a single exposed fracture at a basalt outcrop, and finally to a ponded infiltration test using a pond of 7 by 8 m. In the field experiments, they measure the time-variation of water flux, moisture content, and hydraulic head at various locations, as well as the total inflow rate to the subsurface. Such variations reflect the changes in the geometry and physics of water flow that display chaotic behavior, which they try to reconstruct using the data obtained. In the analysis of experimental data, a chaotic model can be used to predict the long-term bounds on fluid flow and transport behavior, known as the attractor of the system, and to examine the limits of short-term predictability within these bounds. This approach is especially well suited to the need for short-term predictions to support remediation decisions and long-term bounding studies. View-graphs from ten presentations made at the annual meeting held December 3--4, 1997 are included in an appendix to this report.« less
The behavioral dynamics of clinical trials.
Leventhal, H; Nerenz, D R; Leventhal, E A; Love, R R; Bendena, L M
1991-01-01
Two ways of approaching the design of long-term clinical trials are presented and contrasted. The first, termed the "static" view, emphasizes close adherence to formal rules of study design. The second, termed the "dynamic" view, emphasizes the behavioral aspects of patient participation in trials of long duration. The dynamic view is discussed in detail, with discussion of how recruitment of participants, random assignment to conditions, compliance with protocol, and measurement of outcomes are affected by behavioral dynamics. Data from a recently completed tamoxifen toxicity trial are used to illustrate the points and to focus the discussion of behavioral dynamics on the design of a chemoprevention trial for breast cancer using tamoxifen.
NASA Astrophysics Data System (ADS)
LI, Y.; Castelletti, A.; Giuliani, M.
2014-12-01
Over recent years, long-term climate forecast from global circulation models (GCMs) has been demonstrated to show increasing skills over the climatology, thanks to the advances in the modelling of coupled ocean-atmosphere dynamics. Improved information from long-term forecast is supposed to be a valuable support to farmers in optimizing farming operations (e.g. crop choice, cropping time) and for more effectively coping with the adverse impacts of climate variability. Yet, evaluating how valuable this information can be is not straightforward and farmers' response must be taken into consideration. Indeed, while long-range forecast are traditionally evaluated in terms of accuracy by comparison of hindcast and observed values, in the context of agricultural systems, potentially useful forecast information should alter the stakeholders' expectation, modify their decisions and ultimately have an impact on their annual benefit. Therefore, it is more desirable to assess the value of those long-term forecasts via decision-making models so as to extract direct indication of probable decision outcomes from farmers, i.e. from an end-to-end perspective. In this work, we evaluate the operational value of thirteen state-of-the-art long-range forecast ensembles against climatology forecast and subjective prediction (i.e. past year climate and historical average) within an integrated agronomic modeling framework embedding an implicit model of farmers' behavior. Collected ensemble datasets are bias-corrected and downscaled using a stochastic weather generator, in order to address the mismatch of the spatio-temporal scale between forecast data from GCMs and distributed crop simulation model. The agronomic model is first simulated using the forecast information (ex-ante), followed by a second run with actual climate (ex-post). Multi-year simulations are performed to account for climate variability and the value of the different climate forecast is evaluated against the perfect foresight scenario based on the expected crop productivity as well as the land-use decisions. Our results show that not all the products generate beneficial effects to farmers and that the forecast errors might be amplified by the farmers decisions.
Using Simulation to Compare 4 Categories of Intervention for Reducing Cardiovascular Disease Risks
Homer, Jack; Trogdon, Justin; Wile, Kristina; Orenstein, Diane
2014-01-01
The Prevention Impacts Simulation Model (PRISM) projects the multiyear impacts of 22 different interventions aimed at reducing risk of cardiovascular disease. We grouped these into 4 categories: clinical, behavioral support, health promotion and access, and taxes and regulation. We simulated impacts for the United States overall and also for a less-advantaged county with a higher death rate. Of the 4 categories of intervention, taxes and regulation reduce costs the most in the short term (through 2020) and long term (through 2040) and reduce deaths the most in the long term; they are second to clinical interventions in reducing deaths in the short term. All 4 categories combined were required to bring costs and deaths in the less-advantaged county down to the national level. PMID:24832142
Characterizing Smoking and Drinking Abstinence from Social Media.
Tamersoy, Acar; De Choudhury, Munmun; Chau, Duen Horng
2015-09-01
Social media has been established to bear signals relating to health and well-being states. In this paper, we investigate the potential of social media in characterizing and understanding abstinence from tobacco or alcohol use. While the link between behavior and addiction has been explored in psychology literature, the lack of longitudinal self-reported data on long-term abstinence has challenged addiction research. We leverage the activity spanning almost eight years on two prominent communities on Reddit: StopSmoking and StopDrinking. We use the self-reported "badge" information of nearly a thousand users as gold standard information on their abstinence status to characterize long-term abstinence. We build supervised learning based statistical models that use the linguistic features of the content shared by the users as well as the network structure of their social interactions. Our findings indicate that long-term abstinence from smoking or drinking (~one year) can be distinguished from short-term abstinence (~40 days) with 85% accuracy. We further show that language and interaction on social media offer powerful cues towards characterizing these addiction-related health outcomes. We discuss the implications of our findings in social media and health research, and in the role of social media as a platform for positive behavior change and therapy.
Hwang, Eun-Sang; Kim, Hyun-Bum; Lee, Seok; Kim, Min-Ji; Lee, Sung-Ok; Han, Seung-Moo; Maeng, Sungho; Park, Ji-Ho
2017-03-15
Although the incidence rate of dementia is rapidly growing in the aged population, therapeutic and preventive reagents are still suboptimal. Various model systems are used for the development of such reagents in which scopolamine is one of the favorable pharmacological tools widely applied. Loganin is a major iridoid glycoside obtained from Corni fructus (Cornusofficinalis et Zucc) and demonstrated to have anti-inflammatory, anti-tumor and osteoporosis prevention effects. It has also been found to attenuate Aβ-induced inflammatory reactions and ameliorate memory deficits induced by scopolamine. However, there has been limited information available on how loganin affects learning and memory both electrophysiologically and behaviorally. To assess its effect on learning and memory, we investigated the influence of acute loganin administration on long-term potentiation (LTP) using organotypic cultured hippocampal tissues. In addition, we measured the effects of loganin on the behavior performance related to avoidance memory, short-term spatial navigation memory and long-term spatial learning and memory in the passive avoidance, Y-maze, and Morris water maze learning paradigms, respectively. Loganin dose-dependently increased the total activity of fEPSP after high frequency stimulation and attenuated scopolamine-induced blockade of fEPSP in the hippocampal CA1 area. In accordance with these findings, loganin behaviorally attenuated scopolamine-induced shortening of step-through latency in the passive avoidance test, reduced the percent alternation in the Y-maze, and increased memory retention in the Morris water maze test. These results indicate that loganin can effectively block cholinergic muscarinic receptor blockade -induced deterioration of LTP and memory related behavioral performance. Based on these findings, loganin may aid in the prevention and treatment of Alzheimer's disease and learning and memory-deficit disorders in the future. Copyright © 2017 Elsevier Inc. All rights reserved.
Testoni, Guilherme Apolinario; Kim, Sihwan; Pisupati, Anurag; Park, Chung Hae
2018-09-01
We propose a new model for the capillary rise of liquid in flax fibers whose diameter is changed by liquid absorption. Liquid absorption into the flax fibers is taken into account in a new modified Washburn equation by considering the mass of the liquid absorbed inside the fibers as well as that imbibed between the fibers. The change of permeability and hydraulic radius of pores in a fibrous medium due to the fiber swelling is modeled by a statistical approach considering a non-uniform distribution of flax fiber diameter. By comparisons between capillary rise test results and modeling results, we prove the validity of the proposed modified Washburn model to take into account the effects from fiber swelling and liquid absorption on the decrease of capillary rise velocity. The experimental observation of long-term capillary rise tests show that the swelling behavior of the fibers highly packed in a closed volume and its influence on the capillary wicking are different from those of an individual single fiber in a free space. The current approach was useful to characterize the swelling of fibers highly packed in a closed volume and its influence of the long-term behavior of capillary wicking. Copyright © 2018 Elsevier Inc. All rights reserved.
Long-Term Refugee Health: Health Behaviors and Outcomes of Cambodian Refugee and Immigrant Women.
Nelson-Peterman, Jerusha L; Toof, Robin; Liang, Sidney L; Grigg-Saito, Dorcas C
2015-12-01
Refugees in the United States have high rates of chronic disease. Both long-term effects of the refugee experience and adjustment to the U.S. health environment may contribute. While there is significant research on health outcomes of newly resettled refugees and long-term mental health experiences of established refugees, there is currently little information about how the combined effects of the refugee experience and the U.S. health environment are related to health practices of refugees in the years and decades after resettlement. We examined cross-sectional survey data for Cambodian refugee and immigrant women 35 to 60 years old (n = 160) from an established refugee community in Lowell, Massachusetts, to examine the potential contributors to health behaviors and outcomes among refugees and immigrants postresettlement. In our representative sample, we found that smoking and betel nut use were very low (4% each). Fewer than 50% of respondents walked for at least 10 minutes on 2 or more days/week. Using World Health Organization standards for overweight/obese for Asians, 73% of respondents were overweight/obese and 56% were obese, indicating increased risk of chronic disease. Depression was also high in this sample (41%). In multivariate models, higher acculturation and age were associated with walking more often; lower education and higher acculturation were related to higher weight; and being divorced/separated or widowed and being older were related to higher risk of depression. The interrelated complex of characteristics, health behaviors, and health outcomes of refugees merits a multifaceted approach to health education and health promotion for long-term refugee health. © 2015 Society for Public Health Education.
Trannoy, Séverine; Penn, Jill; Lucey, Kenia; Popovic, David; Kravitz, Edward A
2016-04-26
In many animal species, learning and memory have been found to play important roles in regulating intra- and interspecific behavioral interactions in varying environments. In such contexts, aggression is commonly used to obtain desired resources. Previous defeats or victories during aggressive interactions have been shown to influence the outcome of later contests, revealing loser and winner effects. In this study, we asked whether short- and/or long-term behavioral consequences accompany victories and defeats in dyadic pairings between male Drosophila melanogaster and how long those effects remain. The results demonstrated that single fights induced important behavioral changes in both combatants and resulted in the formation of short-term loser and winner effects. These decayed over several hours, with the duration depending on the level of familiarity of the opponents. Repeated defeats induced a long-lasting loser effect that was dependent on de novo protein synthesis, whereas repeated victories had no long-term behavioral consequences. This suggests that separate mechanisms govern the formation of loser and winner effects. These studies aim to lay a foundation for future investigations exploring the molecular mechanisms and circuitry underlying the nervous system changes induced by winning and losing bouts during agonistic encounters.
The Strong African American Families program: longitudinal pathways to sexual risk reduction.
Murry, Velma McBride; Berkel, Cady; Brody, Gene H; Gerrard, Meg; Gibbons, Meg; Gibbons, Frederick X
2007-10-01
To identify the mechanisms by which intervention-induced increases in adaptive parenting were associated with a reduction in sexual risk behavior among rural African American adolescents across a 29-month period. African American families (N = 284) with 11-year-old children in nine rural Georgian counties participated in the 7-week Strong African American Families (SAAF) project. Counties were randomly assigned to intervention or control conditions. The program was evaluated via pretest, posttest, and long-term follow-up interview data collected in the families' homes. The current paper tests a hypothetical model of program efficacy, positing that intervention-induced changes in parenting behaviors would enhance in youth self-pride, which in turn would forecast changes in sexual behaviors measured 29 months after pretest. Compared with controls, parents who participated in SAAF reported increased adaptive universal and racially specific parenting. Furthermore, intervention-induced changes in these parenting behaviors were associated indirectly with sexual risk behavior through adolescent self-pride, peer orientation, and sexual intent. Culturally competent programs, developed through empirical and theoretical research within affected communities, can foster adaptive universal and racially specific parenting, which can have a long-term effect on adolescent sexual risk behavior. Effective strategies for designing and implementing culturally competent programs are discussed.
The longitudinal effects of early behavior problems in the dementia caregiving career.
Gaugler, Joseph E; Kane, Robert L; Kane, Rosalie A; Newcomer, Robert
2005-03-01
Using multiregional, 3-year data from early career dementia caregivers, this study determines how behavior problems that occur early in the caregiving career influence time to nursing home placement and change in burden and depression over time. A Cox proportional hazards model indicated that caregivers who managed frequent behavior problems earlier are more likely to institutionalize. After controlling for important time-varying covariates in a series of growth-curve models, caregivers who were faced with severe, early behavior problems reported greater increases in burden and depression over the 3-year study period. The findings suggest the need to consider experiences early in the dementia caregiving career when accounting for key longitudinal outcomes and also emphasize the importance of attrition when attempting to model the health implications of informal long-term care over time.
NASA Astrophysics Data System (ADS)
Wechsler, N.; Rockwell, T. K.; Klinger, Y.; Agnon, A.; Marco, S.
2012-12-01
Models used to forecast future seismicity make fundamental assumptions about the behavior of faults and fault systems in the long term, but in many cases this long-term behavior is assumed using short-term and perhaps non-representative observations. The question arises - how long of a record is long enough to represent actual fault behavior, both in terms of recurrence of earthquakes and of moment release (aka slip-rate). We test earthquake recurrence and slip models via high-resolution three-dimensional trenching of the Beteiha (Bet-Zayda) site on the Dead Sea Transform (DST) in northern Israel. We extend the earthquake history of this simple plate boundary fault to establish slip rate for the past 3-4kyr, to determine the amount of slip per event and to study the fundamental behavior, thereby testing competing rupture models (characteristic, slip-patch, slip-loading, and Gutenberg Richter type distribution). To this end we opened more than 900m of trenches, mapped 8 buried channels and dated more than 80 radiocarbon samples. By mapping buried channels, offset by the DST on both sides of the fault, we obtained for each an estimate of displacement. Coupled with fault crossing trenches to determine event history, we construct earthquake and slip history for the fault for the past 2kyr. We observe evidence for a total of 9-10 surface-rupturing earthquakes with varying offset amounts. 6-7 events occurred in the 1st millennium, compared to just 2-3 in the 2nd millennium CE. From our observations it is clear that the fault is not behaving in a periodic fashion. A 4kyr old buried channel yields a slip rate of 3.5-4mm/yr, consistent with GPS rates for this segment. Yet in spite of the apparent agreement between GPS, Pleistocene to present slip rate, and the lifetime rate of the DST, the past 800-1000 year period appears deficit in strain release. Thus, in terms of moment release, most of the fault has remained locked and is accumulating elastic strain. In contrast, the preceding 1200 years or so experienced a spate of earthquake activity, with large events along the Jordan Valley segment alone in 31 BCE, 363, 749, and 1033 CE. Thus, the return period appears to vary by a factor of two to four during the historical period in the Jordan Valley as well as at our site. The Beteiha site seems to be affected by both its southern and northern neighboring segments, and there is tentative evidence that earthquakes nucleating in the Jordan Valley (e.g. 749 CE) can rupture through the Galilee step-over to the south of Beteiha, or trigger a smaller event on the Jordan Gorge segment, in which case the historical record will tend to amalgamate any evidence for it into one large event. We offer a model of earthquake slip for this segment, in which the overall slip rate remains constant, yet differing earthquake sizes can occur, depending on the segment from which they originated and the time since the last large event. The rate of earthquake production in this model does not produce a time predictable pattern over a period of 2kyr, and the slip rate varies between the 1st and 2nd millennia CE, as a result of the interplay between coalescing fault segments to the north.
Amphetamine Challenge: A Marker of Brain Function That Mediates Risk for Drug and Alcohol Abuse
2011-08-05
sexual behavior, even if the long-term consequences of those behaviors are harmful. In this study the relationship between the response to a stimulant... sexual behavior, even if the long-term consequences may be harmful. When these tendencies occur together, individuals are more likely to try...this characteristic is sometimes associated with poor control. One possibility is that the same neural system—namely, the mesolimbic dopamine system
Effects of elevated temperature on the viscoplastic modeling of graphite/polymeric composites
NASA Technical Reports Server (NTRS)
Gates, Thomas S.
1991-01-01
To support the development of new materials for the design of next generation supersonic transports, a research program is underway at NASA to assess the long term durability of advanced polymer matrix composites (PMC's). One of main objectives of the program was to explore the effects of elevated temperature (23 to 200 C) on the constitutive model's material parameters. To achieve this goal, test data on the observed nonlinear, stress-strain behavior of IM7/5260 and IM7/8320 composites under tension and compression loading were collected and correlated against temperature. These tests, conducted under isothermal conditions using variable strain rates, included such phenomena as stress relaxation and short term creep. The second major goal was the verification of the model by comparison of analytical predictions and test results for off axis and angle ply laminates. Correlation between test and predicted behavior was performed for specimens of both material systems over a range of temperatures. Results indicated that the model provided reasonable predictions of material behavior in load or strain controlled tests. Periods of loading, unloading, stress relaxation, and creep were accounted for.
Steady state volcanism - Evidence from eruption histories of polygenetic volcanoes
NASA Technical Reports Server (NTRS)
Wadge, G.
1982-01-01
Cumulative volcano volume curves are presented as evidence for steady-state behavior at certain volcanoes and to develop a model of steady-state volcanism. A minimum criteria of five eruptions over a year was chosen to characterize a steady-state volcano. The subsequent model features a constant head of magmatic pressure from a reservoir supplied from depth, a sawtooth curve produced by the magma arrivals or discharge from the subvolcanic reservoir, large volume eruptions with long repose periods, and conditions of nonsupply of magma. The behavior of Mts. Etna, Nyamuragira, and Kilauea are described and show continuous levels of plasma output resulting in cumulative volume increases. Further discussion is made of steady-state andesitic and dacitic volcanism, long term patterns of the steady state, and magma storage, and the lack of a sufficient number of steady-state volcanoes in the world is taken as evidence that further data is required for a comprehensive model.
2015-07-15
Long-term effects on cancer survivors’ quality of life of physical training versus physical training combined with cognitive-behavioral therapy ...COMPARISON OF NEURAL NETWORK AND LINEAR REGRESSION MODELS IN STATISTICALLY PREDICTING MENTAL AND PHYSICAL HEALTH STATUS OF BREAST...34Comparison of Neural Network and Linear Regression Models in Statistically Predicting Mental and Physical Health Status of Breast Cancer Survivors
Garza, Kimberly Bosworth; Harris, Carole V; Bolding, Mark S
2013-01-01
Studies have shown a negative association between value of the future (preference for long-term vs. short-term rewards) and harmful addictive behaviors; however, research in the area of preventive behaviors is limited and has shown conflicting results. The primary objectives were: (1) to examine the association among value of the future and diet and physical activity (PA) behaviors, and (2) to assess whether value of the future explained additional variance in behaviors after controlling for theory-based health beliefs related to coronary heart disease (CHD). An online survey was conducted in adults (N = 172) with no prior history of CHD. A delay discounting task was administered to measure value of the future. Questionnaire items were based on the Health Belief Model (HBM) and included CHD knowledge, perceived risk, perceived severity, perceived benefits of and barriers to behavior change, self-efficacy, cues to action, diet and PA behaviors and demographic variables. High value of the future was associated with younger age, lower BMI, more healthful diet, and increased PA. After controlling for HBM components and demographics, value of the future did not explain any additional variance in diet or PA behaviors. Significant predictors of healthful diet included female gender (P = .013), increased age (P = .029), greater than high school education (P = .023), greater diet-related self-efficacy (P = .021), and not having received a healthcare provider recommendation to improve diet (P = .018). Significant predictors of PA level included income between $20,000 and $69,999 (P = .014), greater exercise-related self-efficacy (P < .001) and not having received a healthcare provider recommendation to increase levels of PA (P = .015). Behaviors to prevent CHD may be associated with a person's outlook on the future; however, self-efficacy was a stronger predictor of behavior. These findings support recommendations for enhancement of diet- and PA-related self-efficacy and problem-solving to address myopia in terms of long-term health benefits. Copyright © 2013 Elsevier Inc. All rights reserved.
The self-care behavior inventory: a model for behavioral instrument development.
McLaughlin, J; Sliepcevich, E M
1985-09-01
The Self-Care Behavior (SCB) Inventory was developed as part of a long-term study of self-care practices of persons who have multiple sclerosis (MS) in Denmark. The universe of behaviors regarding the physical, social, emotional, environmental, and spiritual aspects of coping with the illness was ascertained by informal and formal interviews. Respondents were asked not only what behavior was performed, but also who performed it, how it was performed, why, when, and where it was performed, and where the knowledge to perform the behavior in this manner was acquired, such as a lay-referral network, physician, social worker, spouse, or media. The inventory went through a series of drafts and pre-tests, resulting in a final version that met criteria for validity and reliability. The model presented for the development of the SCB Inventory can be useful for designing behavioral inventories and assessment tools for other chronic conditions such as arthritis, epilepsy, and diabetes.
Boudreaux, Edwin D; Bock, Beth; O'Hea, Erin
2012-03-01
Experiencing a negative consequence related to one's health behavior, like a medical problem leading to an emergency department (ED) visit, can promote behavior change, giving rise to the popular concept of the "teachable moment." However, the mechanisms of action underlying this process of change have received scant attention. In particular, most existing health behavior theories are limited in explaining why such events can inspire short-term change in some and long-term change in others. Expanding on recommendations published in the 2009 Academic Emergency Medicine consensus conference on public health in emergency medicine (EM), we propose a new method for developing conceptual models that explain how negative events, like medical emergencies, influence behavior change, called the Sentinel Event Method. The method itself is atheoretical; instead, it defines steps to guide investigations that seek to relate specific consequences or events to specific health behaviors. This method can be used to adapt existing health behavior theories to study the event-behavior change relationship or to guide formulation of completely new conceptual models. This paper presents the tenets underlying the Sentinel Event Method, describes the steps comprising the process, and illustrates its application to EM through an example of a cardiac-related ED visit and tobacco use. © 2012 by the Society for Academic Emergency Medicine.
Usó-Doménech, Josep-Lluis; Nescolarde-Selva, Josué-Antonio; Lloret-Climent, Miguel; González-Franco, Lucía
2018-03-01
The mathematical submodel ULEX is used to study the dynamic behavior of the green, floral and woody biomass of the main pyrophite shrub species, the gorse (Ulex parviflorus Pourret), and its relationship with other shrub species, typical of a Mediterranean ecosystem. The focus are the ecological conditions of post-fire stage growth, and its efficacy as a protective cover against erosion processes in the short, medium and long term, both in normal conditions and at the limits of desertification conditions. The model sets a target to observe the behavior and to anticipate and consequently intervene with adequate protection, restoration and management measures. Copyright © 2018 Elsevier Inc. All rights reserved.
Gindi, Shahar; Galili, Giora; Volovic-Shushan, Shani; Adir-Pavis, Shirly
2016-01-01
Combat stress reaction (CR) is a syndrome with a wide range of symptoms including changes in soldiers' behaviors, emotional and physiological responses, avoidance and a decrease in both personal and military functioning. The short-term goal in treating CR is a speedy return to healthy functioning, whereas the long-term goal is to prevent the development of PTSD. Previous research has indicated that the achievement of this short-term goal affects the achievement of the long-term goal and vice versa. Effective treatment requires intervention by trained professionals proficient in reinforcing personal and functional identity without psychiatric labelling. The present paper presents a therapeutic model integrating OT in treating CR within a military setting. The model emphasizes the importance of preventing fixation to the role of 'patient' and a rapid return to maximal functioning. Based on Kielhofner's Model of Human Occupation, which aims to promote adaptive and efficient functioning by engaging soldiers in tasks supporting their military identity, empowering functionality, and increasing their perceived competency. The model emphasizes the therapeutic milieu within a military environment. Practical application of this model focuses on interdisciplinary aspects and client-focused application. The paper describes an assessment process for each soldier entering the CR unit and a treatment model integrating OT.
Kichou, Sofiane; Silvestre, Santiago; Nofuentes, Gustavo; Torres-Ramírez, Miguel; Chouder, Aissa; Guasch, Daniel
2016-01-01
Four years׳ behavioral data of thin-film single junction amorphous silicon (a-Si) photovoltaic (PV) modules installed in a relatively dry and sunny inland site with a Continental-Mediterranean climate (in the city of Jaén, Spain) are presented in this article. The shared data contributes to clarify how the Light Induced Degradation (LID) impacts the output power generated by the PV array, especially in the first days of exposure under outdoor conditions. Furthermore, a valuable methodology is provided in this data article permitting the assessment of the degradation rate and the stabilization period of the PV modules. Further discussions and interpretations concerning the data shared in this article can be found in the research paper “Characterization of degradation and evaluation of model parameters of amorphous silicon photovoltaic modules under outdoor long term exposure” (Kichou et al., 2016) [1]. PMID:26977439
Merging analytic and empirical GEO debris synchronization dynamics
NASA Astrophysics Data System (ADS)
Anderson, Paul V.; McKnight, Darren S.; Di Pentino, Frank; Schaub, Hanspeter
2016-09-01
The motion of abandoned satellites near the geostationary (GEO) region has been extensively studied, modeled, and compared to the motion of station-kept, operational satellites, providing insights into the evolution of uncontrolled orbits at GEO. Analytic developments produced a family of curves represented in the ascending node versus inclination space describing the long-term precession of the orbit plane at GEO, and forecasted the clustering of objects at the geopotential wells. However, recent investigations were undertaken to characterize apparent anomalistic behavior of GEO objects and classification of objects into related families. This paper provides a unifying summary of early bottom-up analytical theory with more recent top-down operational observations, highlighting the common linkage between these dimensions of GEO object behavior. This paper also identifies the relevance of these patterns of life tendencies for future operations at and near GEO, and discusses the long-term implications of these patterns of life for space situational awareness activities in this regime.
N-Acetylcysteine reverses cocaine-induced metaplasticity.
Moussawi, Khaled; Pacchioni, Alejandra; Moran, Megan; Olive, M Foster; Gass, Justin T; Lavin, Antonieta; Kalivas, Peter W
2009-02-01
Cocaine addiction is characterized by an impaired ability to develop adaptive behaviors that can compete with cocaine seeking, implying a deficit in the ability to induce plasticity in cortico-accumbens circuitry crucial for regulating motivated behavior. We found that rats withdrawn from cocaine self-administration had a marked in vivo deficit in the ability to develop long-term potentiation (LTP) and long-term depression (LTD) in the nucleus accumbens core subregion after stimulation of the prefrontal cortex. N-acetylcysteine (NAC) treatment prevents relapse in animal models and craving in humans by activating cystine-glutamate exchange and thereby stimulating extrasynaptic metabotropic glutamate receptors (mGluR). NAC treatment of rats restored the ability to induce LTP and LTD by indirectly stimulating mGluR2/3 and mGluR5, respectively. Our findings show that cocaine self-administration induces metaplasticity that inhibits further induction of synaptic plasticity, and this impairment can be reversed by NAC, a drug that also prevents relapse.
Yelland, Erin L; Cless, Adam W; Mallory, Allen B; Cless, Jessica D
2018-06-01
This study examines public perspectives toward sexual behavior within a heterosexually married couple in which one individual has dementia and resides in a long-term care facility. Respondents included 318 adults in the Southern United States. Paired sample t tests were used to understand how the diagnosis of dementia statistically influenced participants' responses, and a logistic regression model was used to understand how a vignette character's sex and respondent characteristics influenced attitudes. Fifty-eight percent of respondents believed that a sexual relationship should be permitted for an adult with dementia, and t tests revealed that dementia had a statistical effect on participants' responses. Sex of the vignette character was not a predictor of attitudes. Participant's qualitative rationales are offered for additional insight. Respondents who felt that a couple should not engage in a sexual relationship commonly cited consent-related issues as their primary concern. Implications for policy development are discussed.
Diana, Mariana C; Peres, Fernanda F; Justi, Veronica; Bressan, Rodrigo A; Lacerda, Acioly L T; Crippa, José Alexandre; Hallak, Jaime E C; Abilio, Vanesssa Costhek
2018-04-14
The treatment of schizophrenia with antipsychotics is still unsatisfactory. Therefore, the search for new treatments and prevention is crucial, and animal models are fundamental tools for this objective. Preclinical and clinical data evidence the antipsychotic profile of sodium nitroprusside (SNP), a nitric oxide (NO) donor. We aimed to investigate SNP in treating and/or preventing the schizophrenia-related behaviors presented by the spontaneously hypertensive rats (SHR) strain. Wistar rats (WR) and SHRs were submitted to two schemes of treatment: (i) a single injection of SNP or vehicle in adulthood; (ii) a long-term early treatment from 30 to 60 postnatal day with SNP or vehicle. The following behaviors were evaluated 24 hours after the acute treatment or 30 days after the long-term treatment: locomotion, social interaction, and contextual fear conditioning. Spontaneously hypertensive rats presented hyperlocomotion, decreased social interaction, and impaired contextual fear conditioning. Single injection of SNP decreased social interaction in both strains and induced a deficit in contextual fear conditioning in WR. Oppositely, early treatment with SNP prevented the behavioral abnormalities in adult SHRs without promoting any effects in WR. Our preclinical data point to SNP as a preventive and safe strategy with a broad range of effectiveness to the positive, negative, and cognitive symptoms of schizophrenia. © 2018 John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Santa, Tomofumi; Kirino, Yutaka; Watanabe, Satoshi; Shirahata, Takaaki; Tsunoda, Makoto
2006-01-01
The terrestrial slug "Limax" is able to acquire short-term and long-term memories during aversive odor-taste associative learning. We investigated the effect of the selective serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) on memory. Behavioral studies indicated that 5,7-DHT impaired short-term memory but not long-term memory. HPLC…
Modeling Long-term Behavior of Stock Market Prices Using Differential Equations
NASA Astrophysics Data System (ADS)
Yang, Xiaoxiang; Zhao, Conan; Mazilu, Irina
2015-03-01
Due to incomplete information available in the market and uncertainties associated with the price determination process, the stock prices fluctuate randomly during a short period of time. In the long run, however, certain economic factors, such as the interest rate, the inflation rate, and the company's revenue growth rate, will cause a gradual shift in the stock price. Thus, in this paper, a differential equation model has been constructed in order to study the effects of these factors on the stock prices. The model obtained accurately describes the general trends in the AAPL and XOM stock price changes over the last ten years.
Extinction events can accelerate evolution.
Lehman, Joel; Miikkulainen, Risto
2015-01-01
Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific in the long term.
Lin, Wenjiao; Qin, Li; Qi, Haiping; Zhang, Deyuan; Zhang, Gui; Gao, Runlin; Qiu, Hong; Xia, Ying; Cao, Ping; Wang, Xiang; Zheng, Wei
2017-05-01
Pure iron as a potential bioresorbable material for bioresorbable coronary scaffold has major disadvantages of slow corrosion and bioresorption. However, so far, there are neither quantitative data of long-term in vivo corrosion nor direct experimental evidence for bioresorption of pure iron and its alloys, which are fundamental and vital for developing novel Fe-based alloys overcoming the intrinsic drawbacks of pure iron. This work systemically investigated scaffold performance, long-term in vivo corrosion behavior and biocompatibility of a nitrided iron coronary scaffold and explored its bioresorption mechanism. It was found that the 70μm Fe-based scaffold was superior to a state of the art Co-Cr alloy stent (Xience Prime™) in terms of crossing profile, recoil and radial strength. Mass loss was 76.0±8.5wt% for the nitrided iron scaffold and 44.2±11.4wt% for the pure iron scaffold after 36months implantation in rabbit abdominal aorta (p<0.05). The Fe-based scaffold showed good long-term biocompatibility in both rabbit and porcine model. Its insoluble corrosion products were demonstrated biosafe and could be cleared away by macrophages from in situ to adventitia to be indiscernible by Micro Computed Tomography and probably finally enter the lymphatics and travel to lymph nodes after 53months implantion in porcine coronary artery. The results indicate that the nitrided iron scaffold with further improvements shall be promising for coronary application. Pure iron as a potential bioresorbable material has major disadvantages of slow corrosion and bioresorption. However, so far, there are neither quantitative data of long-term in vivo corrosion nor direct experimental evidence for bioresorption of pure iron and its alloys. Only this work systemically investigated long-term in vivo corrosion behavior and biocompatibility of a nitrided iron coronary scaffold up to 53months after implantation and explored its bioresorption mechanism. These are fundamental and vital for developing novel Fe-based alloys overcoming the intrinsic drawbacks of pure iron. Novel testing and section-preparing methods were also provided in this work to facilitate future research and development of novel Fe-based alloy scaffolds. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Greater emotional arousal predicts poorer long-term memory of communication skills in couples.
Baucom, Brian R; Weusthoff, Sarah; Atkins, David C; Hahlweg, Kurt
2012-06-01
Many studies have examined the importance of learning skills in behaviorally based couple interventions but none have examined predictors of long-term memory for skills. Associations between emotional arousal and long-term recall of communication skills delivered to couples during a behaviorally based relationship distress prevention program were examined in a sample of 49 German couples. Fundamental frequency (f(0)), a vocal measure of encoded emotional arousal, was measured during pre-treatment couple conflict. Higher levels of f(0) were linked to fewer skills remembered 11 years after completing the program, and women remembered more skills than men. Implications of results for behaviorally based couple interventions are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.
Entangled time in flocking: Multi-time-scale interaction reveals emergence of inherent noise
Murakami, Hisashi
2018-01-01
Collective behaviors that seem highly ordered and result in collective alignment, such as schooling by fish and flocking by birds, arise from seamless shuffling (such as super-diffusion) and bustling inside groups (such as Lévy walks). However, such noisy behavior inside groups appears to preclude the collective behavior: intuitively, we expect that noisy behavior would lead to the group being destabilized and broken into small sub groups, and high alignment seems to preclude shuffling of neighbors. Although statistical modeling approaches with extrinsic noise, such as the maximum entropy approach, have provided some reasonable descriptions, they ignore the cognitive perspective of the individuals. In this paper, we try to explain how the group tendency, that is, high alignment, and highly noisy individual behavior can coexist in a single framework. The key aspect of our approach is multi-time-scale interaction emerging from the existence of an interaction radius that reflects short-term and long-term predictions. This multi-time-scale interaction is a natural extension of the attraction and alignment concept in many flocking models. When we apply this method in a two-dimensional model, various flocking behaviors, such as swarming, milling, and schooling, emerge. The approach also explains the appearance of super-diffusion, the Lévy walk in groups, and local equilibria. At the end of this paper, we discuss future developments, including extending our model to three dimensions. PMID:29689074
Choi, Catherine H.; Schoenfeld, Brian P.; Bell, Aaron J.; Hinchey, Joseph; Rosenfelt, Cory; Gertner, Michael J.; Campbell, Sean R.; Emerson, Danielle; Hinchey, Paul; Kollaros, Maria; Ferrick, Neal J.; Chambers, Daniel B.; Langer, Steven; Sust, Steven; Malik, Aatika; Terlizzi, Allison M.; Liebelt, David A.; Ferreiro, David; Sharma, Ali; Koenigsberg, Eric; Choi, Richard J.; Louneva, Natalia; Arnold, Steven E.; Featherstone, Robert E.; Siegel, Steven J.; Zukin, R. Suzanne; McDonald, Thomas V.; Bolduc, Francois V.; Jongens, Thomas A.; McBride, Sean M. J.
2016-01-01
Fragile X is the most common monogenic disorder associated with intellectual disability (ID) and autism spectrum disorders (ASD). Additionally, many patients are afflicted with executive dysfunction, ADHD, seizure disorder and sleep disturbances. Fragile X is caused by loss of FMRP expression, which is encoded by the FMR1 gene. Both the fly and mouse models of fragile X are also based on having no functional protein expression of their respective FMR1 homologs. The fly model displays well defined cognitive impairments and structural brain defects and the mouse model, although having subtle behavioral defects, has robust electrophysiological phenotypes and provides a tool to do extensive biochemical analysis of select brain regions. Decreased cAMP signaling has been observed in samples from the fly and mouse models of fragile X as well as in samples derived from human patients. Indeed, we have previously demonstrated that strategies that increase cAMP signaling can rescue short term memory in the fly model and restore DHPG induced mGluR mediated long term depression (LTD) in the hippocampus to proper levels in the mouse model (McBride et al., 2005; Choi et al., 2011, 2015). Here, we demonstrate that the same three strategies used previously with the potential to be used clinically, lithium treatment, PDE-4 inhibitor treatment or mGluR antagonist treatment can rescue long term memory in the fly model and alter the cAMP signaling pathway in the hippocampus of the mouse model. PMID:27445731
Lithium-manganese dioxide cells for implantable defibrillator devices-Discharge voltage models
NASA Astrophysics Data System (ADS)
Root, Michael J.
The discharge potential behavior of lithium-manganese dioxide cells designed for implantable cardiac defibrillators was characterized as a function of extent of cell depletion for tests designed to discharge the cells for times between 1 and 7 years. The discharge potential curves may be separated into two segments from 0 ≤ x ≤ ∼0.51 and ∼0.51 ≤ x ≤ 1.00, where x is the dimensionless extent of discharge referenced to the rated cell capacity. The discharge potentials conform to Tafel kinetics in each segment. This behavior allows the discharge potential curves to be predicted for an arbitrary discharge load and long term discharge performance may be predicted from short term test results. The discharge potentials may subsequently be modeled by fitting the discharge curves to empirical functions like polynomials and Padé approximants. A function based on the Nernst equation that includes a term accounting for nonideal interactions between lithium ions and the cathode host material, such as the Redlich-Kister relationship, also may be used to predict discharge behavior.
Egan, Aine; Lennon, Olive; Power, Camillus K; Fullen, Brona M
2017-02-01
To determine patients’ perceptions regarding cognitive behavioral pain management programs, and to determine what, if any, strategies learned on the program patients continue to use long-term to manage their pain. A qualitative, focus-group based study. An outpatient multidisciplinary pain management program in a university teaching hospital. Patients with chronic pain who had previously completed a 4-week cognitive behavioral pain management program (2001–2014). Sixteen patients attended one of four focus groups. A battery of semi-structured questions explored their perceptions of the cognitive behavioral program, and which strategies they found useful and continued to use long-term to manage their pain. Six key themes emerged: 1) universal long-term positive feedback on the utility of the program; 2) the program facilitated long-term changes in daily life; 3) participants now considered themselves as the “new me”; 4) request for more updates on emerging new treatments/pain knowledge; 5) recognizing that the key to maximizing gain from the program was to be open, to listen, and accept; and 6) participants sharing pain management knowledge with others in pain. There was universal positive feedback for the pain management program. Despite the years since they participated in one, patients continue to use key strategies to effectively manage their pain (pacing, relaxation), embedding them in their daily lives to maximize their quality of life.
Wu, Yu-Ling; Kao, Yu-Hsiu
2014-08-01
Skin care is an important responsibility of nurse aides in long-term care facilities, and the nursing knowledge, attitudes, and skills of these aides significantly affects quality of care. However, the work schedule of nurse aides often limits their ability to obtain further education and training. Therefore, developing appropriate and effective training programs for nurse aides is critical to maintaining and improving quality of care in long-term care facilities. This study investigates the effects of multimedia assisted instruction on the skin care learning of nurse aides working in long-term care facilities. A quasi-experimental design and convenient sampling were adopted in this study. Participants included 96 nurse aides recruited from 5 long-term care facilities in Taoyuan County, Taiwan. The experimental group received 3 weeks of multimedia assisted instruction. The control group did not receive this instruction. The Skin Care Questionnaire for Nurse Aides in Long-term Care Facilities and the Skin Care Behavior Checklist were used for assessment before and after the intervention. (1) Posttest scores for skin care knowledge, attitudes, behavior, and the skin care checklist were significantly higher than pretest scores for the intervention group. There was no significant difference between pretest and posttest scores for the control group. (2) A covariance analysis of pretest scores for the two groups showed that the experimental group earned significantly higher average scores than their control group peers for skin care knowledge, attitudes, behavior, and the skin care checklist. The multimedia assisted instruction demonstrated significant and positive effects on the skin care leaning of nurse aides in long-term care facilities. This finding supports the use of multimedia assisted instruction in the education and training of nurse aides in long-term care facilities in the future.
Marital Processes, Arranged Marriage, and Contraception to Limit Fertility
Ghimire, Dirgha J.; Axinn, William G.
2013-01-01
An international transition away from familially-arranged marriages toward participation in spouse choice has endured for decades and continues to spread through rural Asia today. Though we know this transformation has important consequences for childbearing early in marriage, we know much less about longer-term consequences of this marital revolution. This study draws upon theories of family and fertility change and a rural Asian panel study designed to investigate changes in both marital and childbearing behaviors to investigate these long-term consequences. Controlling for social changes that shape both marital practices and childbearing behaviors, and explicitly considering multiple dimensions of marital processes, we find evidence consistent with an independent, long-standing association of participation in spouse choice with higher rates of contraception to terminate childbearing. These results add a new dimension to the evidence linking revolutions in marital behavior to long-term declines in fertility, but also motivate new research to consider a broader range of long-term consequences of changing marital processes. PMID:23709184
Kindling-Induced Changes in Plasticity of the Rat Amygdala and Hippocampus
ERIC Educational Resources Information Center
Schubert, Manja; Siegmund, Herbert; Pape, Hans-Christian; Albrecht, Doris
2005-01-01
Temporal lobe epilepsy (TLE) is often accompanied by interictal behavioral abnormalities, such as fear and memory impairment. To identify possible underlying substrates, we analyzed long-term synaptic plasticity in two relevant brain regions, the lateral amygdala (LA) and the CA1 region of the hippocampus, in the kindling model of epilepsy. Wistar…
Trainee Therapists' Views on the Alliance in Psychotherapy and Supervision: A Longitudinal Study
ERIC Educational Resources Information Center
Ybrandt, H.; Sundin, E. C.; Capone, G.
2016-01-01
The shape of alliance in psychotherapy and supervision using growth curve modeling was examined for clinically inexperienced trainee therapists, who were engaged in long-term cognitive behavioral--or psychodynamic individual psychotherapy at a Psychology Clinic in Sweden. Trainee therapists rated their view of the alliance with their clients and…
Tank System Integrated Model: A Cryogenic Tank Performance Prediction Program
NASA Technical Reports Server (NTRS)
Bolshinskiy, L. G.; Hedayat, A.; Hastings, L. J.; Sutherlin, S. G.; Schnell, A. R.; Moder, J. P.
2017-01-01
Accurate predictions of the thermodynamic state of the cryogenic propellants, pressurization rate, and performance of pressure control techniques in cryogenic tanks are required for development of cryogenic fluid long-duration storage technology and planning for future space exploration missions. This Technical Memorandum (TM) presents the analytical tool, Tank System Integrated Model (TankSIM), which can be used for modeling pressure control and predicting the behavior of cryogenic propellant for long-term storage for future space missions. Utilizing TankSIM, the following processes can be modeled: tank self-pressurization, boiloff, ullage venting, mixing, and condensation on the tank wall. This TM also includes comparisons of TankSIM program predictions with the test data andexamples of multiphase mission calculations.
Chung, Woosuk; Park, Saegeun; Hong, Jiso; Park, Sangil; Lee, Soomin; Heo, Junyoung; Kim, Daesoo; Ko, Youngkwon
2015-10-01
To examine whether neonatal exposure to sevoflurane induces autism-like behaviors in mice. There are continuing reports regarding the potential negative effects of anesthesia on the developing brain. Recently, several studies suggest that neurotoxicity caused by anesthesia may lead to neurodevelopmental impairments. However, unlike reports focusing on learning and memory, there are only a few animal studies focusing on neurodevelopmental disorders after general anesthesia. Therefore, we have focused on autism, a representative neurodevelopmental disorder. Neonatal mice (P6-7) were exposed to a titrated dose of sevoflurane for 6 h. Apoptosis was evaluated by assessing the expression level of cleaved (activated) caspase-3. Autism-like behaviors, general activity, anxiety level, and long-term memory were evaluated with multiple behavioral assays. Western blotting confirmed that neonatal exposure to sevoflurane increased the expression level of activated caspase-3, indicative of apoptosis. Mice exposed to sevoflurane also showed impaired long-term memory in fear tests. However, sevoflurane-exposed mice did not exhibit autism-like features in all of the following assays: social interaction (three-chamber test, caged social interaction), social communication (ultrasonic vocalization test), or repetitive behavior (self-grooming test, digging). There were also no differences in general activity (open field test, home cage activity) and anxiety (open field test, light-dark box) after sevoflurane exposure. Our results confirm previous studies that neonatal sevoflurane exposure causes neurodegeneration and long-term memory impairment in mice. However, sevoflurane did not induce autism-like features. Our study suggests that mice are more vulnerable to long-term memory deficits than autism-like behaviors after exposure to sevoflurane. © 2015 John Wiley & Sons Ltd.
Robison, Lisa S; Popescu, Dominique L; Anderson, Maria E; Beigelman, Steven I; Fitzgerald, Shannon M; Kuzmina, Antonina E; Lituma, David A; Subzwari, Sarima; Michaelos, Michalis; Anderson, Brenda J; Van Nostrand, William E; Robinson, John K
2018-06-04
Cardiovascular exercise (CVE) is associated with healthy aging and reduced risk of disease in humans, with similar benefits seen in animals. Most rodent studies, however, have used shorter intervention periods of a few weeks to a few months, begging questions as to the effects of longer-term, or even life-long, exercise. Additionally, most animal studies have utilized a single exercise treatment group - usually unlimited running wheel access - resulting in large volumes of exercise that are not clinically relevant. It is therefore incumbent to determine the physiological and cognitive/behavioral effects of a range of exercise intensities and volumes over a long-term period that model a lifelong commitment to CVE. In the current study, C57/Bl6 mice remained sedentary or were allowed either 1, 3, or 12 h of access to a running wheel per day, 5 days/weeks, beginning at 3.5-4 months of age. Following an eight-month intervention period, animals underwent a battery of behavioral testing, then euthanized and blood and tissue were collected. Longer access to a running wheel resulted in greater volume and higher running speed, but more breaks in running. All exercise groups showed similarly reduced body weight, increased muscle mass, improved motor function on the rotarod, and reduced anxiety in the open field. While all exercise groups showed increased food intake, this was greatest in the 12 h group but did not differ between 1 h and 3 h mice. While exercise dose-dependently increased working memory performance in the y-maze, the 1 h and 12 h groups showed the largest changes in the mass of many organs, as well as alterations in several behaviors including social interaction, novel object recognition, and Barnes maze performance. These findings suggest that long-term exercise has widespread effects on physiology, behavior, and cognition, which vary by "dose" and measure, and that even relatively small amounts of daily exercise can provide benefits. Copyright © 2018. Published by Elsevier Inc.
Scheinfeld, Emily; Shim, Minsun
2017-05-01
Emerging adulthood (EA) is an important yet overlooked period for developing long-term health behaviors. During these years, emerging adults adopt health behaviors that persist throughout life. This study applies the Integrative Model of Behavioral Prediction (IMBP) to examine the role of childhood parental communication in predicting engagement in healthful eating during EA. Participants included 239 college students, ages 18 to 25, from a large university in the southern United States. Participants were recruited and data collection occurred spring 2012. Participants responded to measures to assess perceived parental communication, eating behaviors, attitudes, subjective norms, and behavioral control over healthful eating. SEM and mediation analyses were used to address the hypotheses posited. Data demonstrated that perceived parent-child communication - specifically, its quality and target-specific content - significantly predicted emerging adults' eating behaviors, mediated through subjective norm and perceived behavioral control. This study sets the stage for further exploration and understanding of different ways parental communication influences emerging adults' healthy behavior enactment.
Hayes, Steven C.; Levin, Michael E.; Plumb-Vilardaga, Jennifer; Villatte, Jennifer L.; Pistorello, Jacqueline
2012-01-01
A number of recent authors have compared acceptance and commitment therapy (ACT) and traditional cognitive behavior therapy (CBT). The present article describes ACT as a distinct and unified model of behavior change, linked to a specific strategy of scientific development, which we term “contextual behavioral science.” We outline the empirical progress of ACT and describe its distinctive development strategy. A contextual behavioral science approach is an inductive attempt to build more adequate psychological systems based on philosophical clarity; the development of basic principles and theories; the development of applied theories linked to basic ones; techniques and components linked to these processes and principles; measurement of theoretically key processes; an emphasis on mediation and moderation in the analysis of applied impact; an interest in effectiveness, dissemination, and training; empirical testing of the research program across a broad range of areas and levels of analysis; and the creation of a more effective scientific and clinical community. We argue that this is a reasonable approach, focused on long-term progress, and that in broad terms it seems to be working. ACT is not hostile to traditional CBT, and is not directly buoyed by whatever weaknesses traditional CBT may have. ACT should be measured at least in part against its own goals as specified by its own developmental strategy. PMID:23611068
Hayes, Steven C; Levin, Michael E; Plumb-Vilardaga, Jennifer; Villatte, Jennifer L; Pistorello, Jacqueline
2013-06-01
A number of recent authors have compared acceptance and commitment therapy (ACT) and traditional cognitive behavior therapy (CBT). The present article describes ACT as a distinct and unified model of behavior change, linked to a specific strategy of scientific development, which we term "contextual behavioral science." We outline the empirical progress of ACT and describe its distinctive development strategy. A contextual behavioral science approach is an inductive attempt to build more adequate psychological systems based on philosophical clarity; the development of basic principles and theories; the development of applied theories linked to basic ones; techniques and components linked to these processes and principles; measurement of theoretically key processes; an emphasis on mediation and moderation in the analysis of applied impact; an interest in effectiveness, dissemination, and training; empirical testing of the research program across a broad range of areas and levels of analysis; and the creation of a more effective scientific and clinical community. We argue that this is a reasonable approach, focused on long-term progress, and that in broad terms it seems to be working. ACT is not hostile to traditional CBT, and is not directly buoyed by whatever weaknesses traditional CBT may have. ACT should be measured at least in part against its own goals as specified by its own developmental strategy. Copyright © 2011. Published by Elsevier Ltd.
FY15 Report on Thermomechanical Testing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Francis D.; Buchholz, Stuart
2015-08-01
Sandia is participating in the third phase of a United States (US)-German Joint Project that compares constitutive models and simulation procedures on the basis of model calculations of the thermomechanical behavior and healing of rock salt (Salzer et al. 2015). The first goal of the project is to evaluate the ability of numerical modeling tools to correctly describe the relevant deformation phenomena in rock salt under various influences. Among the numerical modeling tools required to address this are constitutive models that are used in computer simulations for the description of the thermal, mechanical, and hydraulic behavior of the host rockmore » under various influences and for the long-term prediction of this behavior. Achieving this goal will lead to increased confidence in the results of numerical simulations related to the secure disposal of radioactive wastes in rock salt. Results of the Joint Project may ultimately be used to make various assertions regarding stability analysis of an underground repository in salt during the operating phase as well as long-term integrity of the geological barrier in the post-operating phase A primary evaluation of constitutive model capabilities comes by way of predicting large-scale field tests. The Joint Project partners decided to model Waste Isolation Pilot Plant (WIPP) Rooms B & D which are full-scale rooms having the same dimensions. Room D deformed under natural, ambient conditions while Room B was thermally driven by an array of waste-simulating heaters (Munson et al. 1988; 1990). Existing laboratory test data for WIPP salt were carefully scrutinized and the partners decided that additional testing would be needed to help evaluate advanced features of the constitutive models. The German partners performed over 140 laboratory tests on WIPP salt at no charge to the US Department of Energy (DOE).« less
Elizabeth Reinhardt
2005-01-01
FFE-FVS is a model linking stand development, fuel dynamics, fire behavior and fire effects. It allows comparison of mid- to long-term effects of management alternatives including harvest, mechanical fuel treatment, prescribed fire, salvage, and no action. This fact sheet identifies the intended users and uses, required inputs, what the model does, and tells the user...
Ellison, C. L.; Burby, J. W.; Qin, H.
2015-11-01
One popular technique for the numerical time advance of charged particles interacting with electric and magnetic fields according to the Lorentz force law [1], [2], [3] and [4] is the Boris algorithm. Its popularity stems from simple implementation, rapid iteration, and excellent long-term numerical fidelity [1] and [5]. Excellent long-term behavior strongly suggests the numerical dynamics exhibit conservation laws analogous to those governing the continuous Lorentz force system [6]. Moreover, without conserved quantities to constrain the numerical dynamics, algorithms typically dissipate or accumulate important observables such as energy and momentum over long periods of simulated time [6]. Identification of themore » conservative properties of an algorithm is important for establishing rigorous expectations on the long-term behavior; energy-preserving, symplectic, and volume-preserving methods each have particular implications for the qualitative numerical behavior [6], [7], [8], [9], [10] and [11].« less
Arbitration between controlled and impulsive choices
Economides, M.; Guitart-Masip, M.; Kurth-Nelson, Z.; Dolan, R.J.
2015-01-01
The impulse to act for immediate reward often conflicts with more deliberate evaluations that support long-term benefit. The neural architecture that negotiates this conflict remains unclear. One account proposes a single neural circuit that evaluates both immediate and delayed outcomes, while another outlines separate impulsive and patient systems that compete for behavioral control. Here we designed a task in which a complex payout structure divorces the immediate value of acting from the overall long-term value, within the same outcome modality. Using model-based fMRI in humans, we demonstrate separate neural representations of immediate and long-term values, with the former tracked in the anterior caudate (AC) and the latter in the ventromedial prefrontal cortex (vmPFC). Crucially, when subjects' choices were compatible with long-run consequences, value signals in AC were down-weighted and those in vmPFC were enhanced, while the opposite occurred when choice was impulsive. Thus, our data implicate a trade-off in value representation between AC and vmPFC as underlying controlled versus impulsive choice. PMID:25573670
Spectral and Timing States in Black Hole Binaries
NASA Astrophysics Data System (ADS)
Wilms, J.
Results on the long term variability of galactic black hole candidates are reviewed. I mainly present the results of a > 2 year long campaign with RXTE to monitor the canonical soft state black hole candidates LMC X-1 and LMC X-3 using monthly observations. These observations are presented within the context of the RXTE-ASM long term quasi-periodic variability on timescales of about 150d. For LMC X-3, times of low ASM count rate are correlated with a significant hardening of the X-ray spectrum. The observation with the lowest flux during the whole monitoring campaign can be modeled with a simple γ=1.7 power law -- a hard state spectrum. Since these spectral hardenings occur on the 150 d timescale it is probable that they are associated with periodic changes in the accretion rate. Possible causes for this behavior are discussed, e.g. a wind driven limit-cycle or long-term variability of the donor star.
NASA Astrophysics Data System (ADS)
Gholamhoseini, Alireza
2016-03-01
Relatively little research has been reported on the time-dependent in-service behavior of composite concrete slabs with profiled steel decking as permanent formwork and little guidance is available for calculating long-term deflections. The drying shrinkage profile through the thickness of a composite slab is greatly affected by the impermeable steel deck at the slab soffit, and this has only recently been quantified. This paper presents the results of long-term laboratory tests on composite slabs subjected to both drying shrinkage and sustained loads. Based on laboratory measurements, a design model for the shrinkage strain profile through the thickness of a slab is proposed. The design model is based on some modifications to an existing creep and shrinkage prediction model B3. In addition, an analytical model is developed to calculate the time-dependent deflection of composite slabs taking into account the time-dependent effects of creep and shrinkage. The calculated deflections are shown to be in good agreement with the experimental measurements.
Gámez-Guadix, Manuel; Almendros, Carmen; Carrobles, José Antonio; Muñoz-Rivas, Marina
2012-03-01
The objectives of this study were: (a) to examine the direct and indirect relationships among witnessing interparental violence, parenting practices, and children's long-term psychosocial adjustment; (b) to analyze the possible gender differences in the relationships specified. The sample consisted of 1295 Spanish university students (M age = 21.21, SD = 4.04). We performed statistical analyses using structural equation modeling. The results showed that witnessing parental violence as a child is related to poor long-term psychosocial adjustment during the child's adult years. Furthermore, we found that parenting practices fully mediated the relation between witnessing interparental violence and the child's long-term adjustment. The multigroup analyses showed that most of the relations among the variables did not differ significantly by gender. However, the relation between harsh discipline and antisocial behavior was stronger for males, whereas the relation between harsh discipline and depressive symptoms was stronger for females. Finally, we discuss the implications of these findings for the clinicians and specialists who plan and develop intervention programs for populations at risk.
Immediate perception of a reward is distinct from the reward’s long-term salience
McGinnis, John P; Jiang, Huoqing; Agha, Moutaz Ali; Sanchez, Consuelo Perez; Lange, Jeff; Yu, Zulin; Marion-Poll, Frederic; Si, Kausik
2016-01-01
Reward perception guides all aspects of animal behavior. However, the relationship between the perceived value of a reward, the latent value of a reward, and the behavioral response remains unclear. Here we report that, given a choice between two sweet and chemically similar sugars—L- and D-arabinose—Drosophila melanogaster prefers D- over L- arabinose, but forms long-term memories of L-arabinose more reliably. Behavioral assays indicate that L-arabinose-generated memories require sugar receptor Gr43a, and calcium imaging and electrophysiological recordings indicate that L- and D-arabinose differentially activate Gr43a-expressing neurons. We posit that the immediate valence of a reward is not always predictive of the long-term reinforcement value of that reward, and that a subset of sugar-sensing neurons may generate distinct representations of similar sugars, allowing for rapid assessment of the salient features of various sugar rewards and generation of reward-specific behaviors. However, how sensory neurons communicate information about L-arabinose quality and concentration—features relevant for long-term memory—remains unknown. DOI: http://dx.doi.org/10.7554/eLife.22283.001 PMID:28005005
Research on the time-temperature-damage superposition principle of NEPE propellant
NASA Astrophysics Data System (ADS)
Han, Long; Chen, Xiong; Xu, Jin-sheng; Zhou, Chang-sheng; Yu, Jia-quan
2015-11-01
To describe the relaxation behavior of NEPE (Nitrate Ester Plasticized Polyether) propellant, we analyzed the equivalent relationships between time, temperature, and damage. We conducted a series of uniaxial tensile tests and employed a cumulative damage model to calculate the damage values for relaxation tests at different strain levels. The damage evolution curve of the tensile test at 100 mm/min was obtained through numerical analysis. Relaxation tests were conducted over a range of temperature and strain levels, and the equivalent relationship between time, temperature, and damage was deduced based on free volume theory. The equivalent relationship was then used to generate predictions of the long-term relaxation behavior of the NEPE propellant. Subsequently, the equivalent relationship between time and damage was introduced into the linear viscoelastic model to establish a nonlinear model which is capable of describing the mechanical behavior of composite propellants under a uniaxial tensile load. The comparison between model prediction and experimental data shows that the presented model provides a reliable forecast of the mechanical behavior of propellants.
NASA Astrophysics Data System (ADS)
Saleeb, A. F.; Natsheh, S. H.; Owusu-Danquah, J. S.; Dhakal, B.
2017-05-01
In this work, we address two of the main challenges encountered in constitutive modeling of the thermomechanical behaviors of actuation-based shape memory alloys. Firstly, the complexity of behavior under cyclic thermomechanical loading is properly handled, particularly with regard to assessing the long-term dimensional stability. Secondly, we consider the marked differences in behavior distinguishing virgin-versus-trained SMA material. To this end, we utilize a set of experimental data comprehensive in scope to cover all the anticipated operational conditions for one and same SMA alloy, having a specific chemical composition with fixed heat treatment. More specifically, this includes twenty-four different tests from the recent SMA experimental literature for the Ni49.9Ti50.1 material having austenite finish temperature above 100 °C. Under all the different conditions investigated, the model results were found to be in very good agreement with the experimental measurements.
Cellular level models as tools for cytokine design.
Radhakrishnan, Mala L; Tidor, Bruce
2010-01-01
Cytokines and growth factors are critical regulators that connect intracellular and extracellular environments through binding to specific cell-surface receptors. They regulate a wide variety of immunological, growth, and inflammatory response processes. The overall signal initiated by a population of cytokine molecules over long time periods is controlled by the subtle interplay of binding, signaling, and trafficking kinetics. Building on the work of others, we abstract a simple kinetic model that captures relevant features from cytokine systems as well as related growth factor systems. We explore a large range of potential biochemical behaviors, through systematic examination of the model's parameter space. Different rates for the same reaction topology lead to a dramatic range of biochemical network properties and outcomes. Evolution might productively explore varied and different portions of parameter space to create beneficial behaviors, and effective human therapeutic intervention might be achieved through altering network kinetic properties. Quantitative analysis of the results reveals the basis for tensions among a number of different network characteristics. For example, strong binding of cytokine to receptor can increase short-term receptor activation and signal initiation but decrease long-term signaling due to internalization and degradation. Further analysis reveals the role of specific biochemical processes in modulating such tensions. For instance, the kinetics of cytokine binding and receptor activation modulate whether ligand-receptor dissociation can generally occur before signal initiation or receptor internalization. Beyond analysis, the same models and model behaviors provide an important basis for the design of more potent cytokine therapeutics by providing insight into how binding kinetics affect ligand potency. (c) 2010 American Institute of Chemical Engineers
A model of excitation and adaptation in bacterial chemotaxis.
Hauri, D C; Ross, J
1995-01-01
We present a model of the chemotactic mechanism of Escherichia coli that exhibits both initial excitation and eventual complete adaptation to any and all levels of stimulus ("exact" adaptation). In setting up the reaction network, we use only known interactions and experimentally determined cytosolic concentrations. Whenever possible, rate coefficients are first assigned experimentally measured values; second, we permit some variation in these rate coefficients by using a multiple-well optimization technique and incremental adjustment to obtain values that are sufficient to engender initial response to stimuli (excitation) and an eventual return of behavior to baseline (adaptation). The predictions of the model are similar to the observed behavior of wild-type bacteria in regard to the time scale of excitation in the presence of both attractant and repellent. The model predicts a weaker response to attractant than that observed experimentally, and the time scale of adaptation does not depend as strongly upon stimulant concentration as does that for wild-type bacteria. The mechanism responsible for long-term adaptation is local rather than global: on addition of a repellent or attractant, the receptor types not sensitive to that attractant or repellent do not change their average methylation level in the long term, although transient changes do occur. By carrying out a phenomenological simulation of bacterial chemotaxis, we find that the model is insufficiently sensitive to effect taxis in a gradient of attractant. However, by arbitrarily increasing the sensitivity of the motor to the tumble effector (phosphorylated CheY), we can obtain chemotactic behavior. Images FIGURE 6 FIGURE 7 PMID:7696522
Wang, Su-Chin; Yu, Ching-Len; Chang, Su-Hsien
2017-02-01
The purpose was to examine the effectiveness of music care on cognitive function, depression, and behavioral problems among elderly people with dementia in long-term care facilities in Taiwan. The study had a quasi-experimental, longitudinal research design and used two groups of subjects. Subjects were not randomly assigned to experimental group (n = 90) or comparison group (n = 56). Based on Bandura's social cognition theory, subjects in the experimental group received Kagayashiki music care (KMC) twice per week for 24 weeks. Subjects in the comparison group were provided with activities as usual. Results found, using the control score of the Clifton Assessment Procedures for the Elderly Behavior Rating Scale (baseline) and time of attending KMC activities as a covariate, the two groups of subjects had statistically significant differences in the mini-mental state examination (MMSE). Results also showed that, using the control score of the Cornell Scale for Depression in Dementia (baseline) and MMSE (baseline) as a covariate, the two groups of subjects had statistically significant differences in the Clifton Assessment Procedures for the Elderly Behavior Rating Scale. These findings provide information for staff caregivers in long-term care facilities to develop a non-invasive care model for elderly people with dementia to deal with depression, anxiety, and behavioral problems.
Amin, Maryam S; Harrison, Rosamurd L
2007-01-01
The purpose of this study was to investigate parents' challenges to long-term maintenance of healthy behaviors following their child's dental general anesthesia (GA). Twenty-six in-depth interviews were conducted with parents of children younger than 6 years of age who had dental treatment under GA. The interviews were scheduled at various time periods following the surgery. Compared were the responses of: (1) "relapse" families, whose child had new cavities at the 6-month recall; and (2) "no relapse" families, who were caries-free at recoil. A grounded theory approach to data analysis was used. "Relapse" parents: (1) valued baby teeth differently; (2) perceived their child to be less susceptible to new cavities; and (3) expressed lower self-efficacy for controlling their child's oral health compared to "no relapse" parents. They also appeared to be: (1) in earlier stages of change; (2) less receptive to advice from others, including professionals; and (3) more permissive regarding their child's desires. "Relapse" parents did not seem to have any immediate plans to change their "home-care" behaviors. GA did not appear to affect long-term preventive behaviors for all parents. Readiness to change seemed to be an important predictor of whether parents adopted and maintained preventive behaviors to improve their child's oral health.
Long-term exposure to noise impairs cortical sound processing and attention control.
Kujala, Teija; Shtyrov, Yury; Winkler, Istvan; Saher, Marieke; Tervaniemi, Mari; Sallinen, Mikael; Teder-Sälejärvi, Wolfgang; Alho, Kimmo; Reinikainen, Kalevi; Näätänen, Risto
2004-11-01
Long-term exposure to noise impairs human health, causing pathological changes in the inner ear as well as other anatomical and physiological deficits. Numerous individuals are daily exposed to excessive noise. However, there is a lack of systematic research on the effects of noise on cortical function. Here we report data showing that long-term exposure to noise has a persistent effect on central auditory processing and leads to concurrent behavioral deficits. We found that speech-sound discrimination was impaired in noise-exposed individuals, as indicated by behavioral responses and the mismatch negativity brain response. Furthermore, irrelevant sounds increased the distractibility of the noise-exposed subjects, which was shown by increased interference in task performance and aberrant brain responses. These results demonstrate that long-term exposure to noise has long-lasting detrimental effects on central auditory processing and attention control.
A Simplified Model of Choice Behavior under Uncertainty
Lin, Ching-Hung; Lin, Yu-Kai; Song, Tzu-Jiun; Huang, Jong-Tsun; Chiu, Yao-Chu
2016-01-01
The Iowa Gambling Task (IGT) has been standardized as a clinical assessment tool (Bechara, 2007). Nonetheless, numerous research groups have attempted to modify IGT models to optimize parameters for predicting the choice behavior of normal controls and patients. A decade ago, most researchers considered the expected utility (EU) model (Busemeyer and Stout, 2002) to be the optimal model for predicting choice behavior under uncertainty. However, in recent years, studies have demonstrated that models with the prospect utility (PU) function are more effective than the EU models in the IGT (Ahn et al., 2008). Nevertheless, after some preliminary tests based on our behavioral dataset and modeling, it was determined that the Ahn et al. (2008) PU model is not optimal due to some incompatible results. This study aims to modify the Ahn et al. (2008) PU model to a simplified model and used the IGT performance of 145 subjects as the benchmark data for comparison. In our simplified PU model, the best goodness-of-fit was found mostly as the value of α approached zero. More specifically, we retested the key parameters α, λ, and A in the PU model. Notably, the influence of the parameters α, λ, and A has a hierarchical power structure in terms of manipulating the goodness-of-fit in the PU model. Additionally, we found that the parameters λ and A may be ineffective when the parameter α is close to zero in the PU model. The present simplified model demonstrated that decision makers mostly adopted the strategy of gain-stay loss-shift rather than foreseeing the long-term outcome. However, there are other behavioral variables that are not well revealed under these dynamic-uncertainty situations. Therefore, the optimal behavioral models may not have been found yet. In short, the best model for predicting choice behavior under dynamic-uncertainty situations should be further evaluated. PMID:27582715
Mantha, Katarzyna; Laufer, Benjamin I; Singh, Shiva M
2014-01-01
Fetal alcohol spectrum disorder (FASD) is an umbrella term that refers to a wide range of behavioral and cognitive deficits resulting from prenatal alcohol exposure. It involves changes in brain gene expression that underlie lifelong FASD symptoms. How these changes are achieved from immediate to long-term effects, and how they are maintained, is unknown. We have used the C57BL/6J mouse to assess the dynamics of genomic alterations following binge alcohol exposure. Ethanol-exposed fetal (short-term effect) and adult (long-term effect) brains were assessed for gene expression and microRNA (miRNA) changes using Affymetrix mouse arrays. We identified 48 and 68 differentially expressed genes in short- and long-term groups, respectively. No gene was common between the 2 groups. Short-term (immediate) genes were involved in cellular compromise and apoptosis, which represent ethanol's toxic effects. Long-term genes were involved in various cellular functions, including epigenetics. Using quantitative RT-PCR, we confirmed the downregulation of long-term genes: Camk1g, Ccdc6, Egr3, Hspa5, and Xbp1. miRNA arrays identified 20 differentially expressed miRNAs, one of which (miR-302c) was confirmed. miR-302c was involved in an inverse relationship with Ccdc6. A network-based model involving altered genes illustrates the importance of cellular redox, stress and inflammation in FASD. Our results also support a critical role of apoptosis in FASD, and the potential involvement of miRNAs in the adaptation of gene expression following prenatal ethanol exposure. The ultimate molecular footprint involves inflammatory disease, neurological disease and skeletal and muscular disorders as major alterations in FASD. At the cellular level, these processes represent abnormalities in redox, stress and inflammation, with potential underpinnings to anxiety. © 2014 S. Karger AG, Basel.
Vilarrasa, Víctor; Rutqvist, Jonny; Blanco Martin, Laura; ...
2015-12-31
Expansive soils are suitable as backfill and buffer materials in engineered barrier systems to isolate heat-generating nuclear waste in deep geological formations. The canisters containing nuclear waste would be placed in tunnels excavated at a depth of several hundred meters. The expansive soil should provide enough swelling capacity to support the tunnel walls, thereby reducing the impact of the excavation-damaged zone on the long-term mechanical and flow-barrier performance. In addition to their swelling capacity, expansive soils are characterized by accumulating irreversible strain on suction cycles and by effects of microstructural swelling on water permeability that for backfill or buffer materialsmore » can significantly delay the time it takes to reach full saturation. In order to simulate these characteristics of expansive soils, a dual-structure constitutive model that includes two porosity levels is necessary. The authors present the formulation of a dual-structure model and describe its implementation into a coupled fluid flow and geomechanical numerical simulator. The authors use the Barcelona Basic Model (BBM), which is an elastoplastic constitutive model for unsaturated soils, to model the macrostructure, and it is assumed that the strains of the microstructure, which are volumetric and elastic, induce plastic strain to the macrostructure. The authors tested and demonstrated the capabilities of the implemented dual-structure model by modeling and reproducing observed behavior in two laboratory tests of expansive clay. As observed in the experiments, the simulations yielded nonreversible strain accumulation with suction cycles and a decreasing swelling capacity with increasing confining stress. Finally, the authors modeled, for the first time using a dual-structure model, the long-term (100,000 years) performance of a generic heat-generating nuclear waste repository with waste emplacement in horizontal tunnels backfilled with expansive clay and hosted in a clay rock formation. The thermo-hydro-mechanical results of the dual-structure model were compared with those of the standard single-structure BBM. The main difference between the simulation results from the two models is that the dual-structure model predicted a time to fully saturate the expansive clay barrier on the order of thousands of years, whereas the standard single-structure BBM yielded a time on the order of tens of years. These examples show that a dual-structure model, such as the one presented here, is necessary to properly model the thermo-hydro-mechanical behavior of expansive soils.« less
Semple, Bridgette D.; Lee, Sangmi; Sadjadi, Raha; Fritz, Nora; Carlson, Jaclyn; Griep, Carrie; Ho, Vanessa; Jang, Patrice; Lamb, Annick; Popolizio, Beth; Saini, Sonia; Bazarian, Jeffrey J.; Prins, Mayumi L.; Ferriero, Donna M.; Basso, D. Michele; Noble-Haeusslein, Linda J.
2015-01-01
Sports-related concussions are particularly common during adolescence, a time when even mild brain injuries may disrupt ongoing brain maturation and result in long-term complications. A recent focus on the consequences of repetitive concussions among professional athletes has prompted the development of several new experimental models in rodents, as well as the revision of guidelines for best management of sports concussions. Here, we consider the utility of rodent models to understand the functional consequences and pathobiology of concussions in the developing brain, identifying the unique behavioral and pathological signatures of concussive brain injuries. The impact of repetitive concussions on behavioral consequences and injury progression is also addressed. In particular, we focus on the epidemiological, clinical, and experimental evidence underlying current recommendations for physical and cognitive rest after concussion, and highlight key areas in which further research is needed. Lastly, we consider how best to promote recovery after injury, recognizing that optimally timed, activity-based rehabilitative strategies may hold promise for the adolescent athlete who has sustained single or repetitive concussions. The purpose of this review is to inform the clinical research community as it strives to develop and optimize evidence-based guidelines for the concussed adolescent, in terms of both acute and long-term management. PMID:25883586
Gentile, Douglas A; Anderson, Craig A; Yukawa, Shintaro; Ihori, Nobuko; Saleem, Muniba; Ming, Lim Kam; Shibuya, Akiko; Liau, Albert K; Khoo, Angeline; Bushman, Brad J; Rowell Huesmann, L; Sakamoto, Akira
2009-06-01
Although dozens of studies have documented a relationship between violent video games and aggressive behaviors, very little attention has been paid to potential effects of prosocial games. Theoretically, games in which game characters help and support each other in nonviolent ways should increase both short-term and long-term prosocial behaviors. We report three studies conducted in three countries with three age groups to test this hypothesis. In the correlational study, Singaporean middle-school students who played more prosocial games behaved more prosocially. In the two longitudinal samples of Japanese children and adolescents, prosocial game play predicted later increases in prosocial behavior. In the experimental study, U.S. undergraduates randomly assigned to play prosocial games behaved more prosocially toward another student. These similar results across different methodologies, ages, and cultures provide robust evidence of a prosocial game content effect, and they provide support for the General Learning Model.
Gentile, Douglas A.; Anderson, Craig A.; Yukawa, Shintaro; Ihori, Nobuko; Saleem, Muniba; Ming, Lim Kam; Shibuya, Akiko; Liau, Albert K.; Khoo, Angeline; Bushman, Brad J.; Huesmann, L. Rowell; Sakamoto, Akira
2009-01-01
Although dozens of studies have documented a relation between violent video games and aggressive behaviors, very little attention has been paid to potential effects of prosocial games. Theoretically, games in which game characters help and support each other in nonviolent ways should increase both short-term and long-term prosocial behaviors. We report three studies conducted in three countries with three age groups to test this hypothesis. In the correlational study, Singaporean middle-school students who played more prosocial games behaved more prosocially. In the two longitudinal samples of Japanese children and adolescents, prosocial game play predicted later increases in prosocial behavior. In the experimental study, U.S. undergraduates randomly assigned to play prosocial games behaved more prosocially toward another student. These similar results across different methodologies, ages, and cultures provide robust evidence a prosocial game content effect, and provide support for the General Learning Model. PMID:19321812
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallego-Marcos, Fernando; Sánchez, Rafael; Platero, Gloria
We analyze long-range transport through an ac driven triple quantum dot with a single electron. Resonant transitions between separated and detuned dots are mediated by the exchange of n photons with the time-dependent field. An effective model is proposed in terms of second order (cotunneling) processes which dominate the long-range transport between the edge quantum dots. The ac field renormalizes the inter dot hopping, modifying the level hybridization. It results in a non-trivial behavior of the current with the frequency and amplitude of the external ac field.
Long-Term Refugee Health: Health Behaviors and Outcomes of Cambodian Refugee and Immigrant Women
ERIC Educational Resources Information Center
Nelson-Peterman, Jerusha L.; Toof, Robin; Liang, Sidney L.; Grigg-Saito, Dorcas C.
2015-01-01
Refugees in the United States have high rates of chronic disease. Both long-term effects of the refugee experience and adjustment to the U.S. health environment may contribute. While there is significant research on health outcomes of newly resettled refugees and long-term mental health experiences of established refugees, there is currently…
Pöttker, Bruno; Stöber, Franziska; Hummel, Regina; Angenstein, Frank; Radyushkin, Konstantin; Goldschmidt, Jürgen; Schäfer, Michael K E
2017-12-01
Traumatic brain injury (TBI) is a leading cause of disability and death and survivors often suffer from long-lasting motor impairment, cognitive deficits, anxiety disorders and epilepsy. Few experimental studies have investigated long-term sequelae after TBI and relations between behavioral changes and neural activity patterns remain elusive. We examined these issues in a murine model of TBI combining histology, behavioral analyses and single-photon emission computed tomography (SPECT) imaging of regional cerebral blood flow (CBF) as a proxy for neural activity. Adult C57Bl/6N mice were subjected to unilateral cortical impact injury and investigated at early (15-57 days after lesion, dal) and late (184-225 dal) post-traumatic time points. TBI caused pronounced tissue loss of the parietal cortex and subcortical structures and enduring neurological deficits. Marked perilesional astro- and microgliosis was found at 57 dal and declined at 225 dal. Motor and gait pattern deficits occurred at early time points after TBI and improved over the time. In contrast, impaired performance in the Morris water maze test and decreased anxiety-like behavior persisted together with an increased susceptibility to pentylenetetrazole-induced seizures suggesting alterations in neural activity patterns. Accordingly, SPECT imaging of CBF indicated asymmetric hemispheric baseline neural activity patterns. In the ipsilateral hemisphere, increased baseline neural activity was found in the amygdala. In the contralateral hemisphere, homotopic to the structural brain damage, the hippocampus and distinct cortex regions displayed increased baseline neural activity. Thus, regionally elevated CBF along with behavioral alterations indicate that increased neural activity is critically involved in the long-lasting consequences of TBI.
Chen, Yung-Chi
2014-05-01
This study used data from Waves I and II of the Taiwan Educational Panel Survey (TEPS) to explore the potential short-term and long-term effects of parental illness and health condition on children's behavioral and educational functioning. A sample of 11,018 junior high school students and their parents and teachers in Taiwan were included in this present study. The results supported previous work that parental illness may place children at slight risk for poor psychosocial adjustment and behavioral problems. Parental illness was associated with lower adaptive skills and more behavioral problems in children. Children of ill parents showed resilience in their educational functioning in the event of parental illness as children's academic achievement and learning skills were not related to parental illness/health condition.
Behavioral and physiological consequences of enrichment loss in rats
Smith, Brittany L.; Lyons, Carey E; Correa, Fernanda Guilhaume; Benoit, Stephen C.; Myers, Brent; Solomon, Matia B.; Herman, James P.
2017-01-01
Significant loss produces the highest degree of stress and compromised well-being in humans. Current rodent models of stress involve the application of physically or psychologically aversive stimuli, but do not address the concept of loss. We developed a rodent model for significant loss, involving removal of long-term access to a rewarding enriched environment. Our results indicate that removal from environmental enrichment produces a profound behavioral and physiological phenotype with depression-like qualities, including helplessness behavior, hypothalamo-pituitary-adrenocortical axis dysregulation and overeating. Importantly, this enrichment removal phenotype was prevented by antidepressant treatment. Furthermore, the effects of enrichment removal do not occur following relief from chronic stress and are not duplicated by loss of exercise or social contact. PMID:28012292
Tysseling, Vicki M.; Janes, Lindsay; Imhoff, Rebecca; Quinlan, Katharina A.; Lookabaugh, Brad; Ramalingam, Shyma; Heckman, C.J.; Tresch, Matthew C.
2013-01-01
Mouse models are commonly used for identifying the behavioral consequences of genetic modifications, progression or recovery from disease or trauma models, and understanding spinal circuitry. Electromyographic recordings (EMGs) are recognized as providing information not possible from standard behavioral analyses involving gross behavioral or kinematic assessments. We describe here a method for recording from relatively large numbers of muscles in behaving mice. We demonstrate the use of this approach for recording from hindlimb muscles bilaterally in intact animals, following spinal cord injury, and during the progression of ALS. This design can be used in a variety of applications in order to characterize the coordination strategies of mice in health and disease. PMID:23369875
Transformative professional development of physicians as educators: assessment of a model.
Armstrong, Elizabeth G; Doyle, Jennifer; Bennett, Nancy L
2003-07-01
Medical education reform has been the clarion call of U.S. medical educators and policymakers for two decades. To foster change and seed reform, Harvard Medical School created a professional development program for physicians and scientists actively engaged in educating future physicians that sought to transform both participants and their schools. This study focused on identifying the long-term effects of a professional development program on physician educators. A follow-up survey of the 1995-97 cohorts of the Harvard Macy Program for Physician Educators was conducted by sending the 99 program participants a questionnaire two years after their participation. Main outcome measures studied were individual changes as reflected in participants' self-reported shifts in teaching behaviors, academic productivity, career advancement, and sense of commitment. A total of 63 participants completed the questionnaire, for a response rate of 63.6%. Two years following participation in the program, a majority (88.8%) of respondents reported that participation had significantly affected their professional development, including long-term changes in teaching behaviors (77.8%), engagement in new educational activities from committee work (86%) to grant funding (52.4%), and renewed vitality/identification of themselves as educators. Long-term follow-up of participants enrolled in an intensive program for physician educators suggests that professional development programs that create an immersion experience designed in a high-challenge, high-support environment, emphasizing experiential and participatory activities can change behaviors in significant ways, and that these changes endure over time.
NASA Astrophysics Data System (ADS)
Guzman-Morales, J.; Gershunov, A.
2015-12-01
Santa Ana Winds (SAWs) are an integral feature of the regional climate of Southern California/Northern Baja California region. In spite of their tremendous episodic impacts on the health, economy and mood of the region, climate-scale behavior of SAW is poorly understood. In the present work, we identify SAWs in mesoscale dynamical downscaling of a global reanalysis product and construct an hourly SAW catalogue spanning 65 years. We describe the long-term SAW climatology at relevant time-space resolutions, i.e, we developed local and regional SAW indices and analyse their variability on hourly, daily, annual, and multi-decadal timescales. Local and regional SAW indices are validated with available anemometer observations. Characteristic behaviors are revealed, e.g. the SAW intensity-duration relationship. At interdecadal time scales, we find that seasonal SAW activity is sensitive to prominent large-scale low-frequency modes of climate variability rooted in the tropical and north Pacific ocean-atmosphere system that are also known to affect the hydroclimate of this region. Lastly, we do not find any long-term trend in SAW frequency and intensity as previously reported. Instead, we identify a significant long-term trend in SAW behavior whereby contribution of extreme SAW events to total seasonal SAW activity has been increasing at the expense of moderate events. These findings motivate further investigation on SAW evolution in future climate and its impact on wildfires.
Mesa-Gresa, Patricia; Ramos-Campos, Marta; Redolat, Rosa
2016-05-01
Environmental enrichment (EE) is an experimental model which is believed to counteract some of the effects induced by stressors, although few studies have exposed rodents simultaneously to EE and stress. Our aim was to compare the short- and long-term effects of different housing conditions in mice submitted to chronic stress. 128 NMRI male mice arrived at our laboratory on postnatal day (PND) 21. During Phase I (PND 28), animals were randomly assigned to four experimental conditions: 1) EE+STRESS: mice housed in EE and submitted to social stress (n=32); 2) EE+NO STRESS: mice housed in EE without stress (n=32); 3) SE+STRESS: mice maintained in standard conditions (SE) and submitted to social stress (n=32); and 4) SE+NO STRESS (n=32). At the end of Phase I (PND 77), one cohort of 32 animals was used for behavioral assessment whereas another cohort of 32 was sacrificed for corticosterone analysis. Results indicated that EE animals showed less body weight, higher water and food intake, diminished anxiety response and decreased motor and exploratory behavior than SE mice. Mice exposed to stress gained less body weight, showed higher food and fluid intake and displayed decreased exploratory behavior than non-stressed mice. Furthermore, EE+STRESS group displayed significantly higher corticosterone levels than EE+NO STRESS group whereas EE+NO STRESS group showed lower levels than SE+NO STRESS. On PND 83, Phase II of the study began. Animals (n=96) were assigned to two different housing conditions: EE (n=48) and SE (n=48). On PND 112, corticosterone analysis (n=32) and behavioral study (n=64) were done. The factor "Housing Phase II" reached statistical significance. Results indicated that EE animals showed lower body weight and higher fluid intake than SE group, as well as decreased anxiety. No clear effects on motor and exploratory behavior or learning were observed. When long-term effects were analyzed, results indicated that "Initial Housing" condition was significant: animals allocated in EE during Phase I of the study showed higher corticosterone levels, lower body weight and higher fluid intake than SE mice. "Initial Stress" had significant long-term actions on food intake and exploratory behavior: animals initially reared under stress conditions displayed higher food intake and lower exploration levels on the hole-board test than non-stressed mice. In the elevated plus-maze, there were significant interactions between factors "Initial Housing" and "Initial Stress". These factors did not reach statistical significance for motor activity or learning task. We can conclude that both short- and long-term effects of housing conditions are evident for corticosterone levels, body weight and fluid intake. Social stress induced short-term effects on body weight, food and fluid intake and exploratory behavior whereas long-acting effects were reflected on food intake and exploratory behavior. Further studies are needed in order to explore more in depth behavioral and physiological consequences of social stress and environmental enrichment. Copyright © 2016. Published by Elsevier Inc.
Evaluation and prediction of long-term environmental effects of nonmetallic materials, second phase
NASA Technical Reports Server (NTRS)
1983-01-01
Changes in the functional properties of a number of nonmetallic materials were evaluated experimentally as a function of simulated space environments and to use such data to develop models for accelerated test methods useful for predicting such behavioral changes. The effects of changed particle irradiations on candidate space materials are evaluated.
ERIC Educational Resources Information Center
Alahyane, Nadia; Pelisson, Denis
2005-01-01
The adaptation of saccadic eye movements to environmental changes occurring throughout life is a good model of motor learning and motor memory. Numerous studies have analyzed the behavioral properties and neural substrate of oculomotor learning in short-term saccadic adaptation protocols, but to our knowledge, none have tested the persistence of…
Accountability and the Kepler Public Schools. A Technical-Behavioral Analysis. Appendix A.
ERIC Educational Resources Information Center
Levine, Donald M.; Hahn, Peter T.
This study examines the effectiveness of an accountability system--Alter--whose aim is to facilitate long-term planning. The purpose of the study was to develop a model that school systems can use in implementing accountability systems. The project explored the idea that when formal management systems are introduced into schools, they ignore…
Evolution of Cygnus X-3 through its Radio and X-ray States
NASA Astrophysics Data System (ADS)
Szostek, A.; Zdziarski, A. A.; McCollough, M. L.
2009-05-01
Based on X-ray spectra and studies of the long-term correlated behavior between radio and soft X-ray, we present a detailed evolution of Cyg X-3 through its radio and X-ray states. We comment on the nature of the hard X-ray tail and possible Simbol X contribution in constraining the models.
Extinction Events Can Accelerate Evolution
Lehman, Joel; Miikkulainen, Risto
2015-01-01
Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific in the long term. PMID:26266804
ERIC Educational Resources Information Center
Saavedra, Lissette M.; Silverman, Wendy K.; Morgan-Lopez, Antonio A.; Kurtines, William M.
2010-01-01
Background: The present study's aim was to examine the long-term effects (8 to 13 years post-treatment; M = 9.83 years; SD = 1.71) of the most widely used treatment approaches of exposure-based cognitive behavioral treatment for phobic and anxiety disorders in children and adolescents (i.e., group treatment and two variants of individual…
ERIC Educational Resources Information Center
Brotman, Laurie Miller; Gouley, Kathleen Kiely; Huang, Keng-Yen; Rosenfelt, Amanda; O'Neal, Colleen; Klein, Rachel G.; Shrout, Patrick
2008-01-01
This article presents long-term effects of a preventive intervention for young children at high risk for antisocial behavior. Ninety-two children (M age = 4 years) were randomly assigned to an 8-month family intervention or no-intervention control condition and assessed 4 times over a 24-month period. Intent-to-treat analyses revealed significant…
ERIC Educational Resources Information Center
Arch, Joanna J.; Craske, Michelle G.
2012-01-01
Nadler (this issue), in his commentary of our article, "Addressing Relapse in Cognitive Behavioral Therapy for Panic Disorder: Methods for Optimizing Long-Term Treatment Outcomes" (Arch & Craske, 2011), argues that we misrepresent the role of panic attacks within learning theory and overlook cognitive treatment targets. He presents several case…
Implicit attitudes towards smoking predict long-term relapse in abstinent smokers.
Spruyt, Adriaan; Lemaigre, Valentine; Salhi, Bihiyga; Van Gucht, Dinska; Tibboel, Helen; Van Bockstaele, Bram; De Houwer, Jan; Van Meerbeeck, Jan; Nackaerts, Kristiaan
2015-07-01
It has previously been argued that implicit attitudes toward substance-related cues drive addictive behavior. Nevertheless, it remains an open question whether behavioral markers of implicit attitude activation can be used to predict long-term relapse. The main objective of this study was to examine the relationship between implicit attitudes toward smoking-related cues and long-term relapse in abstaining smokers. Implicit attitudes toward smoking-related cues were assessed by means of the Implicit Association Test (IAT) and the evaluative priming task (EPT). Both measures were completed by a group of smokers who volunteered to quit smoking (patient group) and a group of nonsmokers (control group). Participants in the patient group completed these measures twice: once prior to smoking cessation and once after smoking cessation. Relapse was assessed by means of short telephone survey, 6 months after completion of the second test session. EPT scores obtained prior to smoking cessation were related to long-term relapse and correlated with self-reported nicotine dependence as well as daily cigarette consumption. In contrast, none of the behavioral outcome measures were found to correlate with the IAT scores. These findings corroborate the idea that implicit attitudes toward substance-related cues are critically involved in long-term relapse. A potential explanation for the divergent findings obtained with the IAT and EPT is provided.
Hamer, Mary; Semple, Bridgette D.; Noble-Haeusslein, Linda J.; Baghchechi, Mohsen; Hiroto, Alex; Hartman, Richard E.; Obenaus, André
2016-01-01
Mild traumatic brain injuries can lead to long-lasting cognitive and motor deficits, increasing the risk of future behavioral, neurological, and affective disorders. Our study focused on long-term behavioral deficits after repeated injury in which mice received either a single mild CHI (mCHI), a repeated mild CHI (rmCHI) consisting of one impact to each hemisphere separated by 3 days, or a moderate controlled cortical impact injury (CCI). Shams received only anesthesia. Behavioral tests were administered at 1, 3, 5, 7, and 90 days post-injury (dpi). CCI animals showed significant motor and sensory deficits in the early (1–7 dpi) and long-term (90 dpi) stages of testing. Interestingly, sensory and subtle motor deficits in rmCHI animals were found at 90 dpi. Most importantly, depression-like behaviors and social passiveness were observed in rmCHI animals at 90 dpi. These data suggest that mild concussive injuries lead to motor and sensory deficits and affective disorders that are not observed after moderate TBI. PMID:26796696
ERIC Educational Resources Information Center
Sumi, W. Carl; Woodbridge, Michelle W.; Javitz, Harold S.; Thornton, S. Patrick; Wagner, Mary; Rouspil, Kristen; Yu, Jennifer W.; Seeley, John R.; Walker, Hill M.; Golly, Annemieke; Small, Jason W.; Feil, Edward G.; Severson, Herbert H.
2013-01-01
This article reports on the effectiveness of First Step to Success, a secondary-level intervention appropriate for students in early elementary school who experience moderate to severe behavior problems and are at risk for academic failure. The authors demonstrate the intervention's short-term effects on multiple behavioral and academic outcomes…
Enhancing the quality of supportive supervisory behavior in long-term care facilities.
McGillis Hall, Linda; McGilton, Katherine S; Krejci, Janet; Pringle, Dorothy; Johnston, Erin; Fairley, Laura; Brown, Maryanne
2005-04-01
The practices of managers and registered nurses (RNs) in long-term care facilities are frequently ineffective in assisting the licensed practical nurses (LPNs) and healthcare aides (HCAs) whom they supervise. Little research exists that examines the area of supportive relationships between nursing staff and supervisors in these settings. The purpose of this study was to gather data that could improve management practices in long-term care residential facilities and enhance the quality of the supervisory relationships between supervisors (nurse managers and RNs) and care providers (HCAs and LPNs) in these settings. The study also identified factors that influence the supervisors' ability to establish supportive relationships with care providers. The challenges and barriers to nurse managers and leaders related to enacting supportive behaviors are discussed as well as their implications for long-term care settings.
NASA Astrophysics Data System (ADS)
Wang, Xuan; Guo, Kun; Lu, Xiaolin
2016-07-01
The behavior information of financial market plays a more and more important role in modern economic system. The behavior information reflected in INTERNET search data has already been used in short-term prediction for exchange rate, stock market return, house price and so on. However, the long-run relationship between behavior information and financial market fluctuation has not been studied systematically. Further, most traditional statistic methods and econometric models could not catch the dynamic and non-linear relationship. An attention index of CNY/USD exchange rate is constructed based on search data from 360 search engine of China in this paper. Then the DCCA and Thermal Optimal Path methods are used to explore the long-run dynamic relationship between CNY/USD exchange rate and the corresponding attention index. The results show that the significant interdependency exists and the change of exchange rate is 1-2 days lag behind the attention index.
Modeling human-climate interaction
NASA Astrophysics Data System (ADS)
Jacoby, Henry D.
If policymakers and the public are to be adequately informed about the climate change threat, climate modeling needs to include components far outside its conventional boundaries. An integration of climate chemistry and meteorology, oceanography, and terrestrial biology has been achieved over the past few decades. More recently the scope of these studies has been expanded to include the human systems that influence the planet, the social and ecological consequences of potential change, and the political processes that lead to attempts at mitigation and adaptation. For example, key issues—like the relative seriousness of climate change risk, the choice of long-term goals for policy, and the analysis of today's decisions when uncertainty may be reduced tomorrow—cannot be correctly understood without joint application of the natural science of the climate system and social and behavioral science aspects of human response. Though integration efforts have made significant contributions to understanding of the climate issue, daunting intellectual and institutional barriers stand in the way of needed progress. Deciding appropriate policies will be a continuing task over the long term, however, so efforts to extend the boundaries of climate modeling and assessment merit long-term attention as well. Components of the effort include development of a variety of approaches to analysis, the maintenance of a clear a division between close-in decision support and science/policy research, and the development of funding institutions that can sustain integrated research over the long haul.
NASA Astrophysics Data System (ADS)
Shvartsman, Leonid D.; Tverskoy, Boris
2015-03-01
We present system for long-term continuous PPG monitoring, and physical model for PPG analysis. The system is based on ideology of light scattering modulated by the process of RBC aggregation. OXIRATE's system works in reflection geometry. The sensor is tiny, completely mobile phone compatible, it can be placed nearly everywhere on the body surface. These technical features allow all-night comfortable PPG monitoring that was performed and analyzed. We can define various sleep stages on the basis of different reproducible time-behavior of PPG signal. Our system of PPG monitoring was used also for reflection pulse oximetry and for extreme PPG studies, such as diving.
Time-series photometric spot modeling. I - Parameter study and application to HD 17433 = VY Arietis
NASA Technical Reports Server (NTRS)
Strassmeier, K. G.; Bopp, B. W.
1992-01-01
New UBVRI photometry of the active chromosphere binary HD 17433 (VY) Ari from 1987 through 1991 is presented, and the long-term and short-term spot behavior is studied. A 0.2 mag variation of the mean brightness and a maximum wave amplitude of up to 0.4 mag in 1988 are found. The newly measured photometric period of 16.42 d suggests asynchronous rotation of the primary component by about 30 percent.
Modeling deformation behavior of the baseball.
Nicholls, Rochelle Llewelyn; Miller, Karol; Elliott, Bruce C
2005-02-01
Regulating ball response to impact is one way to control ball exit velocity in baseball. This is necessary to reduce injuries to defensive players and maintain the balance between offense and defense in the game. This paper presents a model for baseball velocity-dependent behavior. Force-displacement data were obtained using quasi-static compression tests to 50% of ball diameter (n = 70 baseballs). The force-displacement curves for a very stiff baseball (Model B) and a softer type (Model C) were characterized by a Mooney-Rivlin model using implicit finite element analysis (ANSYS software, version 6.1). Agreement between experimental and numerical results was excellent for both Model B (C(10) = 0, C(01) = 3.7e(6) Pa) and Model C (C(10) = 0, C(01) = 2.6e(6) Pa). However, this material model was not available in the ANSYS/LSDYNA explicit dynamic software (version 6.1) used to quantify the transient behavior of the ball. Therefore the modeling process was begun again using a linear viscoelastic material. G(infinity), the long-term shear modulus of the material, was determined by the same implicit FEA procedure. Explicit FEA was used to quantify the time-dependent response of each ball in terms of instantaneous shear modulus (G0) and a decay term (beta). The results were evaluated with respect to published experimental data for the ball coefficient of restitution at five velocities (13.4-40.2 ms(-1)) and were in agreement with the experimental values. The model forms the basis for future research on baseball response to impact with the bat.
Cognitive Model of Animal Behavior to Comprehend an Aspect of Decision-Making
NASA Astrophysics Data System (ADS)
Migita, Masao; Moriyama, Tohru
2004-08-01
Most animal behaviors are considered to have been evolved through their own courses of natural selection. Since mechanisms of natural selection depend tightly on environments in which animals of interest inhabit, the environment for an animal appears a priori, and stimulus-response (S-R) relationships are stable as long as it returns constant benefit. We claim, however, no environment for an animal cannot be regarded as a priori and any animal can exhibit more elaborated behavior than S-R. In other words, every animal is more or less cognitive in terms that it may modify a meaning of stimulus. We introduce a minimal model to demonstrate the cognitive aspect of the pill bug's turn alternation (TA) behavior. The simulated pill bug can modify its own response pattern to the stimulus of water, though stable response appears to be prerequisite to TA behavior.
de Miranda, Aline Silva; Brant, Fátima; Vieira, Luciene Bruno; Rocha, Natália Pessoa; Vieira, Érica Leandro Marciano; Rezende, Gustavo Henrique Souza; de Oliveira Pimentel, Pollyana Maria; Moraes, Marcio F D; Ribeiro, Fabíola Mara; Ransohoff, Richard M; Teixeira, Mauro Martins; Machado, Fabiana Simão; Rachid, Milene Alvarenga; Teixeira, Antônio Lúcio
2017-11-01
Cerebral malaria (CM) is a life-threatening complication of Plasmodium falciparum infection, which can result in long-term cognitive and behavioral deficits despite successful anti-malarial therapy. Due to the substantial social and economic burden of CM, the development of adjuvant therapies is a scientific goal of highest priority. Apart from vascular and immune responses, changes in glutamate system have been reported in CM pathogenesis suggesting a potential therapeutic target. Based on that, we hypothesized that interventions in the glutamatergic system induced by blockage of N-methyl-D-aspartate (NMDA) receptors could attenuate experimental CM long-term cognitive and behavioral outcomes. Before the development of evident CM signs, susceptible mice infected with Plasmodium berghei ANKA (PbA) strain were initiated on treatment with dizocilpine maleate (MK801, 0.5 mg/kg), a noncompetitive NMDA receptor antagonist. On day 5 post-infection, mice were treated orally with a 10-day course chloroquine (CQ, 30 mg/kg). Control mice also received saline, CQ or MK801 + CQ therapy. After 10 days of cessation of CQ treatment, magnetic resonance images (MRI), behavioral and immunological assays were performed. Indeed, MK801 combined with CQ prevented long-term memory impairment and depressive-like behavior following successful PbA infection resolution. In addition, MK801 also modulated the immune system by promoting a balance of TH1/TH2 response and upregulating neurotrophic factors levels in the frontal cortex and hippocampus. Moreover, hippocampus abnormalities observed by MRI were partially prevented by MK801 treatment. Our results indicate that NMDA receptor antagonists can be neuroprotective in CM and could be a valuable adjuvant strategy for the management of the long-term impairment observed in CM.
Lifestyle modification in the management of the metabolic syndrome: achievements and challenges
Grave, Riccardo Dalle; Calugi, Simona; Centis, Elena; Marzocchi, Rebecca; Ghoch, Marwan El; Marchesini, Giulio
2010-01-01
Lifestyle modification based on behavior therapy is the most important and effective strategy to manage the metabolic syndrome. Modern lifestyle modification therapy combines specific recommendations on diet and exercise with behavioral and cognitive strategies. The intervention may be delivered face-to-face or in groups, or in groups combined with individual sessions. The main challenge of treatment is helping patients maintain healthy behavior changes in the long term. In the last few years, several strategies have been evaluated to improve the long-term effect of lifestyle modification. Promising results have been achieved by combining lifestyle modification with pharmacotherapy, using meals replacement, setting higher physical activity goals, and long-term care. The key role of cognitive processes in the success/failure of weight loss and maintenance suggests that new cognitive procedures and strategies should be included in the traditional lifestyle modification interventions, in order to help patients build a mind-set favoring long-term lifestyle changes. These new strategies raise optimistic expectations for an effective treatment of metabolic syndrome with lifestyle modifications, provided public health programs to change the environment where patients live support them. PMID:21437107
Low, Lucie A.; Bauer, Lucy C.; Pitcher, Mark H.; Bushnell, M. Catherine
2016-01-01
Abstract With the increased interest in longitudinal brain imaging of awake rodents, it is important to understand both the short-term and long-term effects of restraint on sensory and emotional processing in the brain. To understand the effects of repeated restraint on pain behaviors and stress responses, we modeled a restraint protocol similar to those used to habituate rodents for magnetic resonance imaging scanning, and studied sensory sensitivity and stress hormone responses over 5 days. To uncover lasting effects of training, we also looked at responses to the formalin pain test 2 weeks later. We found that while restraint causes acute increases in the stress hormone corticosterone, it can also cause lasting reductions in nociceptive behavior in the formalin test, coupled with heightened corticosterone levels and increased activation of the “nociceptive” central nucleus of the amygdala, as seen by Fos protein expression. These results suggest that short-term repeated restraint, similar to that used to habituate rats for awake functional brain scanning, could potentially cause long-lasting changes in physiological and brain responses to pain stimuli that are stress-related, and therefore could potentially confound the functional activation patterns seen in awake rodents in response to pain stimuli. PMID:27058679
Low, Lucie A; Bauer, Lucy C; Pitcher, Mark H; Bushnell, M Catherine
2016-08-01
With the increased interest in longitudinal brain imaging of awake rodents, it is important to understand both the short-term and long-term effects of restraint on sensory and emotional processing in the brain. To understand the effects of repeated restraint on pain behaviors and stress responses, we modeled a restraint protocol similar to those used to habituate rodents for magnetic resonance imaging scanning, and studied sensory sensitivity and stress hormone responses over 5 days. To uncover lasting effects of training, we also looked at responses to the formalin pain test 2 weeks later. We found that while restraint causes acute increases in the stress hormone corticosterone, it can also cause lasting reductions in nociceptive behavior in the formalin test, coupled with heightened corticosterone levels and increased activation of the "nociceptive" central nucleus of the amygdala, as seen by Fos protein expression. These results suggest that short-term repeated restraint, similar to that used to habituate rats for awake functional brain scanning, could potentially cause long-lasting changes in physiological and brain responses to pain stimuli that are stress-related, and therefore could potentially confound the functional activation patterns seen in awake rodents in response to pain stimuli.
Wu, Han-Fang; Chen, Po See; Chen, Yi-Ju; Lee, Chi-Wei; Chen, I-Tuan; Lin, Hui-Ching
2017-09-01
The amygdala plays crucial roles in socio-emotional behavior and cognition, both of which are abnormal in autism spectrum disorder (ASD). Valproic acid (VPA)-exposed rat offspring have demonstrated ASD phenotypes and amygdala excitatory/inhibitory imbalance. However, the role of glutamatergic synapses in this imbalance remains unclear. In this study, we used a VPA-induced ASD-like model to assess glutamatergic synapse-dependent long-term depression (LTD) and depotentiation (DPT) in the amygdala. We first confirmed that the VPA-exposed offspring exhibited sociability deficits, anxiety, depression-like behavior, and abnormal nociception thresholds. Then, electrophysiological examination showed a significantly decreased paired-pulse ratio in the amygdala. In addition, both NMDA-dependent LTD and DPT were absent from the amygdala. Furthermore, we found that the levels of glycogen synthase kinase3β (GSK-3β) phosphorylation and β-catenin were significantly higher in the amygdala of the experimental animals than in the controls. Local infusion of phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin into the amygdala reversed the increased phosphorylation level and impaired social behavior. Taken together, the results suggested that NMDA receptor-related synaptic plasticity is dysfunctional in VPA-exposed offspring. In addition, GSK-3β in the amygdala is critical for synaptic plasticity at the glutamatergic synapses and is related to social behavior. Its role in the underlying mechanism of ASD merits further investigation.
Rayen, Ine; van den Hove, Daniël L; Prickaerts, Jos; Steinbusch, Harry W; Pawluski, Jodi L
2011-01-01
Depression during pregnancy and the postpartum period is a growing health problem, which affects up to 20% of women. Currently, selective serotonin reuptake inhibitor (SSRIs) medications are commonly used for treatment of maternal depression. Unfortunately, there is very little research on the long-term effect of maternal depression and perinatal SSRI exposure on offspring development. Therefore, the aim of this study was to determine the role of exposure to fluoxetine during development on affective-like behaviors and hippocampal neurogenesis in adolescent offspring in a rodent model of maternal depression. To do this, gestationally stressed and non-stressed Sprague-Dawley rat dams were treated with either fluoxetine (5 mg/kg/day) or vehicle beginning on postnatal day 1 (P1). Adolescent male and female offspring were divided into 4 groups: 1) prenatal stress+fluoxetine exposure, 2) prenatal stress+vehicle, 3) fluoxetine exposure alone, and 4) vehicle alone. Adolescent offspring were assessed for anxiety-like behavior using the Open Field Test and depressive-like behavior using the Forced Swim Test. Brains were analyzed for endogenous markers of hippocampal neurogenesis via immunohistochemistry. Results demonstrate that maternal fluoxetine exposure reverses the reduction in immobility evident in prenatally stressed adolescent offspring. In addition, maternal fluoxetine exposure reverses the decrease in hippocampal cell proliferation and neurogenesis in maternally stressed adolescent offspring. This research provides important evidence on the long-term effect of fluoxetine exposure during development in a model of maternal adversity.
Hunt, Hillary R; Gross, Alan M
2009-11-01
Obesity is a world-wide health concern approaching epidemic proportions. Successful long-term treatment involves a combination of bariatric surgery, diet, and exercise. Social cognitive models, such as the Theory of Reasoned Action (TRA) and the Theory of Planned Behavior (TPB), are among the most commonly tested theories utilized in the prediction of exercise. As exercise is not a completely volitional behavior, it is hypothesized that the TPB is a superior theoretical model for the prediction of exercise intentions and behavior. This study tested validity of the TPB in a sample of bariatric patients and further validated its improvement over the TRA in predicting exercise adherence at different operative stages. Results generally confirmed research hypotheses. Superiority of the TPB model was validated in this sample of bariatric patients, and Perceived Behavioral Control emerged as the single-best predictor of both exercise intentions and self-reported behavior. Finally, results suggested that both subjective norms and attitudes toward exercise played a larger role in the prediction of intention and behavior than previously reported.
Vincke, Eveline
2017-01-01
Previous research indicates that drinking large quantities of alcohol could function as a short-term mating strategy for young adults in mating situations. However, no study investigated whether this is actually the case. Therefore, in this article, the link between short-term mating motivations and drinking high amounts of alcohol is tested. First, a survey study ( N = 345) confirmed that young adults who engage in binge drinking are more short-term oriented in their mating strategy than young adults who never engage in binge drinking. Also, the more short-term-oriented young adults were in their mating strategy, the more often binge drinking behavior was conducted. In addition, an experimental study ( N = 229) empirically verified that short-term mating motivations increase young adults' drinking behavior, more so than long-term mating motivations. Results of the experiment clearly showed that young men and young women are triggered to drink more alcoholic beverages in a short-term mating situation compared to a long-term mating situation. Furthermore, the mating situation also affected young adults' perception of drinking behavior. Young adults in a short-term mating context perceived a higher amount of alcoholic beverages as heavy drinking compared to peers in a long-term mating context. These findings confirm that a high alcohol consumption functions as a short-term mating strategy for both young men and young women. Insights gained from this article might be of interest to institutions aimed at targeting youth alcohol (ab)use.
Williams, Geoffrey C.; Niemiec, Christopher P.; Patrick, Heather; Ryan, Richard M.; Deci, Edward L.
2010-01-01
Background The Public Health Service (PHS) Guideline for Treating Tobacco Use and Dependence (1) recommends supporting autonomy and perceived competence to facilitate tobacco abstinence. Purpose To evaluate the effectiveness of an intensive tobacco-dependence intervention based on self-determination theory (SDT) and intended to support autonomy and perceived competence in facilitating long-term tobacco abstinence. Methods One thousand and six adult smokers were recruited into a randomized cessation-induction trial. Community care participants received cessation pamphlets and information on local treatment programs. Intervention participants received the same materials and were asked to meet four times with counselors over six months to discuss their health in a manner intended to support autonomy and perceived competence. The primary outcome was 24-month prolonged abstinence from tobacco. The secondary outcome was 7-day point prevalence tobacco abstinence at 24 months post-intervention. Results Smokers in the intervention were more likely to attain both tobacco abstinence outcomes and these effects were partially mediated by change in both autonomous self-regulation and perceived competence from baseline to six months. Structural equation modeling confirmed the SDT model of health-behavior change in facilitating long-term tobacco abstinence. Conclusions An intervention based on SDT and consistent with the PHS Guideline, which was intended to support autonomy and perceived competence, facilitated long-term tobacco abstinence. PMID:19373517
Williams, Geoffrey C; Niemiec, Christopher P; Patrick, Heather; Ryan, Richard M; Deci, Edward L
2009-06-01
The Public Health Service (PHS) Guideline for Treating Tobacco Use and Dependence (Fiore et al. 2000) recommends supporting autonomy and perceived competence to facilitate tobacco abstinence. The aim of the study was to evaluate the effectiveness of an intensive tobacco-dependence intervention based on self-determination theory (SDT) and intended to support autonomy and perceived competence in facilitating long-term tobacco abstinence. One thousand and six adult smokers were recruited into a randomized cessation-induction trial. Community care participants received cessation pamphlets and information on local treatment programs. Intervention participants received the same materials and were asked to meet four times with counselors over 6 months to discuss their health in a manner intended to support autonomy and perceived competence. The primary outcome was 24-month prolonged abstinence from tobacco. The secondary outcome was 7-day point prevalence tobacco abstinence at 24 months postintervention. Smokers in the intervention were more likely to attain both tobacco abstinence outcomes and these effects were partially mediated by change in both autonomous self-regulation and perceived competence from baseline to 6 months. Structural equation modeling confirmed the SDT model of health-behavior change in facilitating long-term tobacco abstinence. An intervention based on SDT and consistent with the PHS Guideline, which was intended to support autonomy and perceived competence, facilitated long-term tobacco abstinence.
NASA Astrophysics Data System (ADS)
Li, Yu; Giuliani, Matteo; Castelletti, Andrea
2016-04-01
Recent advances in modelling of coupled ocean-atmosphere dynamics significantly improved skills of long-term climate forecast from global circulation models (GCMs). These more accurate weather predictions are supposed to be a valuable support to farmers in optimizing farming operations (e.g. crop choice, cropping and watering time) and for more effectively coping with the adverse impacts of climate variability. Yet, assessing how actually valuable this information can be to a farmer is not straightforward and farmers' response must be taken into consideration. Indeed, in the context of agricultural systems potentially useful forecast information should alter stakeholders' expectation, modify their decisions, and ultimately produce an impact on their performance. Nevertheless, long-term forecast are mostly evaluated in terms of accuracy (i.e., forecast quality) by comparing hindcast and observed values and only few studies investigated the operational value of forecast looking at the gain of utility within the decision-making context, e.g. by considering the derivative of forecast information, such as simulated crop yields or simulated soil moisture, which are essential to farmers' decision-making process. In this study, we contribute a step further in the assessment of the operational value of long-term weather forecasts products by embedding these latter into farmers' behavioral models. This allows a more critical assessment of the forecast value mediated by the end-users' perspective, including farmers' risk attitudes and behavioral patterns. Specifically, we evaluate the operational value of thirteen state-of-the-art long-range forecast products against climatology forecast and empirical prediction (i.e. past year climate and historical average) within an integrated agronomic modeling framework embedding an implicit model of the farmers' decision-making process. Raw ensemble datasets are bias-corrected and downscaled using a stochastic weather generator, in order to address the mismatch of the spatio-temporal scale between forecast data from GCMs and our model. For each product, the experiment is composed by two cascade simulations: 1) an ex-ante simulation using forecast data, and 2) an ex-post simulation with observations. Multi-year simulations are performed to account for climate variability, and the operational value of the different forecast products is evaluated against the perfect foresight on the basis of expected crop productivity as well as the final decisions under different decision-making criterions. Our results show that not all products generate beneficial effects to farmers' performance, and the forecast errors might be amplified due to farmers' decision-making process and risk attitudes, yielding little or even worse performance compared with the empirical approaches.
Caring about Tomorrow: Future Orientation, Environmental Attitudes and Behaviors
ERIC Educational Resources Information Center
Carmi, Nurit
2013-01-01
Almost any pro-environmental behavior arouses a temporal conflict, as protecting long-term interests requires the sacrifice of short-term ones. Similarly, many health promoting behaviors may involve present discomfort for the sake of future well-being. In both contexts, health or environmental, developed future orientation (FO) is required to…
Bupropion (Wellbutrin) and Pregnancy
... have any long-term effect on my baby’s behavior and development? There is very little known about long term effects on children exposed to bupropion during pregnancy. One study has suggested an association between prenatal exposure to ...
Lee, Tae Wha; Yim, Eunsil; Cho, Eunhee; Chung, Jane
2014-08-01
To examine, in beneficiaries with long-term care (LTC) insurance (LTCI) with dementia in Korea, changes in cognitive function, behavioral symptoms, and physical function over time in relation to LTCI service type and to determine the 2-year effects of service type on those health outcomes. Secondary analyses of the existing LTCI data set from 2008 to 2010. South Korea. LTCI beneficiaries with dementia aged 65 and older (N=31,319). Participants were divided according to the service type that they were receiving home care (HC), institutional care (IC), and combined care (CC). A LTC approval checklist was used to determine the level of LTCI coverage of each participant and to assess cognitive function, behavioral symptoms, and physical function. Linear mixed models and multiple regression models were used. There were significant differences in cognitive function, behavioral symptoms, and physical function at baseline between individuals receiving the three service types (P<.001) and overall improvements in those outcomes over 2 years in the three groups (P<.001). After limiting the sample to those who had received LTCI services for the full 2 years (2008-2010) and adjusting for baseline characteristics, individuals receiving HC were more likely to have better cognitive and physical function than those receiving IC or CC but were likely to have more behavioral symptoms 2 years after the LTCI enrollment (P<.001). LTCI service type (HC, IC, CC) predicted cognitive function, behavioral symptoms, and physical function at 2-year follow-up in beneficiaries with dementia. Further research is necessary to examine the effect of LTC services on health outcomes in a longer observational cohort. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.
Financial market dynamics: superdiffusive or not?
NASA Astrophysics Data System (ADS)
Devi, Sandhya
2017-08-01
The behavior of stock market returns over a period of 1-60 d has been investigated for S&P 500 and Nasdaq within the framework of nonextensive Tsallis statistics. Even for such long terms, the distributions of the returns are non-Gaussian. They have fat tails indicating that the stock returns do not follow a random walk model. In this work, a good fit to a Tsallis q-Gaussian distribution is obtained for the distributions of all the returns using the method of Maximum Likelihood Estimate. For all the regions of data considered, the values of the scaling parameter q, estimated from 1 d returns, lie in the range 1.4-1.65. The estimated inverse mean square deviations (beta) show a power law behavior in time with exponent values between -0.91 and -1.1 indicating normal to mildly subdiffusive behavior. Quite often, the dynamics of market return distributions is modelled by a Fokker-Plank (FP) equation either with a linear drift and a nonlinear diffusion term or with just a nonlinear diffusion term. Both of these cases support a q-Gaussian distribution as a solution. The distributions obtained from current estimated parameters are compared with the solutions of the FP equations. For negligible drift term, the inverse mean square deviations (betaFP) from the FP model follow a power law with exponent values between -1.25 and -1.48 indicating superdiffusion. When the drift term is non-negligible, the corresponding betaFP do not follow a power law and become stationary after certain characteristic times that depend on the values of the drift parameter and q. Neither of these behaviors is supported by the results of the empirical fit.
Yee, Nicole; Plassmann, Kerstin; Fuchs, Eberhard
2011-09-01
Clinical studies have implicated adolescence as an important and vulnerable period during which traumatic experiences can predispose individuals to anxiety and mood disorders. As such, a stress model in juvenile rats (age 27-29 d) was previously developed to investigate the long-term effects of stress exposure during adolescence on behavior and physiology. This paradigm involves exposing rats to different stressors on consecutive days over a 3-day period. Here, we studied the effects of juvenile stress on long-term core body temperature regulation and acute stress-induced hyperthermia (SIH) responses using telemetry. We found no differences between control and juvenile stress rats in anxiety-related behavior on the elevated plus maze, which we attribute to stress associated with surgical implantation of telemetry devices. This highlights the severe impact of surgical stress on the results of subsequent behavioral measurements. Nonetheless, juvenile stress disrupted the circadian rhythmicity of body temperature and decreased circadian amplitude. It also induced chronic hypothermia during the dark phase of the day, when rats are most active. When subjected to acute social defeat stress as adults, juvenile stress had no impact on the SIH response relative to controls. However, 24 h later, juvenile stress rats displayed an elevated SIH response in anticipation of social defeat when re-exposed to the social defeat environment. Taken together, our findings indicate that juvenile stress can induce long-term alterations in body temperature regulation and heighten the increase in temperature associated with anticipation of social defeat. The outcomes of behavioral measurements in these experiments, however, are severely affected by surgical stress. Copyright © 2011 Elsevier Inc. All rights reserved.
Lysenko, Larisa V.; Kim, Jeesun; Henry, Cassandra; Tyrtyshnaia, Anna; Kohnz, Rebecca A.; Madamba, Francisco; Simon, Gabriel M.; Kleschevnikova, Natalia E.; Nomura, Daniel K.; Ezekowitz, R . Alan B.; Kleschevnikov, Alexander M.
2014-01-01
Genetic alterations or pharmacological treatments affecting endocannabinoid signaling have profound effects on synaptic and neuronal properties and, under certain conditions, may improve higher brain functions. Down syndrome (DS), a developmental disorder caused by triplication of chromosome 21, is characterized by deficient cognition and inevitable development of the Alzheimer disease (AD) type pathology during aging. Here we used JZL184, a selective inhibitor of monoacylglycerol lipase (MAGL), to examine the effects of chronic MAGL inhibition on the behavioral, biochemical, and synaptic properties of aged Ts65Dn mice, a genetic model of DS. In both Ts65Dn mice and their normosomic (2N) controls, JZL184-treatment increased brain levels of 2-arachidonoylglycerol (2-AG) and decreased levels of its metabolites such as arachidonic acid, prostaglandins PGD2, PGE2, PGFα, and PGJ2. Enhanced spontaneous locomotor activity of Ts65Dn mice was reduced by the JZL184-treatement to the levels observed in 2N animals. Deficient long-term memory was also improved, while short-term and working types of memory were unaffected. Furthermore, reduced hippocampal long-term potentiation (LTP) was increased in the JZL184-treated Ts65Dn mice to the levels observed in 2N mice. Interestingly, changes in synaptic plasticity and behavior were not observed in the JZL184-treated 2N mice suggesting that the treatment specifically attenuated the defects in the trisomic animals. The JZL184-treatment also reduced the levels of Aβ40 and Aβ42, but had no effect on the levels of full length APP and BACE1 in both Ts65Dn and 2N mice. These data show that chronic MAGL inhibition improves the behavior and brain functions in a DS model suggesting that pharmacological targeting of MAGL may be considered as a perspective new approach for improving cognition in DS. PMID:25474204
Effects of experimental nitrogen deposition on peatland carbon pools and fluxes: a modeling analysis
NASA Astrophysics Data System (ADS)
Wu, Y.; Blodau, C.; Moore, T. R.; Bubier, J. L.; Juutinen, S.; Larmola, T.
2014-07-01
Nitrogen (N) pollution of peatlands alters their carbon (C) balances, yet long-term effects and controls are poorly understood. We applied the model PEATBOG to analyze impacts of long-term nitrogen (N) fertilization on C cycling in an ombrotrophic bog. Simulations of summer gross ecosystem production (GEP), ecosystem respiration (ER) and net ecosystem exchange (NEE) were evaluated against 8 years of observations and extrapolated for 80 years to identify potential effects of N fertilization and factors influencing model behavior. The model successfully simulated moss decline and raised GEP, ER and NEE on fertilized plots. GEP was systematically overestimated in the model compared to the field data due to high tolerance of Sphagnum to N deposition in the model. Model performance regarding the 8 year response of GEP and NEE to N was improved by introducing an N content threshold shifting the response of photosynthesis capacity to N content in shrubs and graminoids from positive to negative at high N contents. Such changes also eliminated the competitive advantages of vascular species and led to resilience of mosses in the long-term. Regardless of the large changes of C fluxes over the short-term, the simulated GEP, ER and NEE after 80 years depended on whether a graminoid- or shrub-dominated system evolved. When the peatland remained shrub-Sphagnum dominated, it shifted to a C source after only 10 years of fertilization at 6.4 g N m-2 yr-1, whereas this was not the case when it became graminoid-dominated. The modeling results thus highlight the importance of ecosystem adaptation and reaction of plant functional types to N deposition, when predicting the future C balance of N-polluted cool temperate bogs.
Bourtchouladze, Rusiko; Lidge, Regina; Catapano, Ray; Stanley, Jennifer; Gossweiler, Scott; Romashko, Darlene; Scott, Rod; Tully, Tim
2003-01-01
Mice carrying a truncated form of cAMP-responsive element binding protein (CREB)-binding protein (CBP) show several developmental abnormalities similar to patients with Rubinstein-Taybi syndrome (RTS). RTS patients suffer from mental retardation, whereas long-term memory formation is defective in mutant CBP mice. A critical role for cAMP signaling during CREB-dependent long-term memory formation appears to be evolutionarily conserved. From this observation, we reasoned that drugs that modulate CREB function by enhancing cAMP signaling might yield an effective treatment for the memory defect(s) of CBP+/− mice. To this end, we designed a cell-based drug screen and discovered inhibitors of phosphodiesterase 4 (PDE4) to be particularly effective enhancers of CREB function. We extend previous behavioral observations by showing that CBP+/− mutants have impaired long-term memory but normal learning and short-term memory in an object recognition task. We demonstrate that the prototypical PDE4 inhibitor, rolipram, and a novel one (HT0712) abolish the long-term memory defect of CBP+/− mice. Importantly, the genetic lesion in CBP acts specifically to shift the dose sensitivity for HT0712 to enhance memory formation, which conveys molecular specificity on the drug's mechanism of action. Our results suggest that PDE4 inhibitors may be used to treat the cognitive dysfunction of RTS patients. PMID:12930888
NASA Astrophysics Data System (ADS)
Zhou, H. W.; Yi, H. Y.; Mishnaevsky, L.; Wang, R.; Duan, Z. Q.; Chen, Q.
2017-05-01
A modeling approach to time-dependent property of Glass Fiber Reinforced Polymers (GFRP) composites is of special interest for quantitative description of long-term behavior. An electronic creep machine is employed to investigate the time-dependent deformation of four specimens of dog-bond-shaped GFRP composites at various stress level. A negative exponent function based on structural changes is introduced to describe the damage evolution of material properties in the process of creep test. Accordingly, a new creep constitutive equation, referred to fractional derivative Maxwell model, is suggested to characterize the time-dependent behavior of GFRP composites by replacing Newtonian dashpot with the Abel dashpot in the classical Maxwell model. The analytic solution for the fractional derivative Maxwell model is given and the relative parameters are determined. The results estimated by the fractional derivative Maxwell model proposed in the paper are in a good agreement with the experimental data. It is shown that the new creep constitutive model proposed in the paper needs few parameters to represent various time-dependent behaviors.
Promoting Healthy Weight with "Stability Skills First": A Randomized Trial
ERIC Educational Resources Information Center
Kiernan, Michaela; Brown, Susan D.; Schoffman, Danielle E.; Lee, Katherine; King, Abby C.; Taylor, C. Barr; Schleicher, Nina C.; Perri, Michael G.
2013-01-01
Objective: Although behavioral weight-loss interventions produce short-term weight loss, long-term maintenance remains elusive. This randomized trial examined whether learning a novel set of "stability skills" before losing weight improved long-term weight management. Stability skills were designed to optimize individuals' current…
The Psychometricization of Sigfluence.
ERIC Educational Resources Information Center
Loase, John Frederick
The English language lacks a word that means long-term interpersonal influence of one person toward another. This failing likely conditions people to be superficial in their thinking, and consequently in their behavior. A new term, sigfluence, has been coined to define positive, long-term, significant, impactful, interpersonal influence. One of…
Greenlee, Heather; Ogden Gaffney, Ann; Aycinena, A Corina; Koch, Pam; Contento, Isobel; Karmally, Wahida; Richardson, John M; Shi, Zaixing; Lim, Emerson; Tsai, Wei-Yann; Santella, Regina M; Blaner, William S; Clugston, Robin D; Cremers, Serge; Pollak, Susan; Sirosh, Iryna; Crew, Katherine D; Maurer, Matthew; Kalinsky, Kevin; Hershman, Dawn L
2016-11-01
Among Hispanic breast cancer survivors, we examined the long-term effects of a short-term culturally based dietary intervention on increasing fruits/vegetables (F/V), decreasing fat, and changing biomarkers associated with breast cancer recurrence risk. Spanish-speaking women (n = 70) with a history of stage 0-III breast cancer who completed treatment were randomized to ¡Cocinar Para Su Salud! (n = 34), a culturally based 9-session program (24 hours over 12 weeks, including nutrition education, cooking classes, and food-shopping field trips), or a control group (n = 36, written dietary recommendations for breast cancer survivors). Diet recalls, fasting blood, and anthropometric measures were collected at baseline, 6, and 12 months. We report changes between groups at 12 months in dietary intake and biomarkers using 2-sample Wilcoxon t tests and generalized estimating equation (GEE) models. At 12 months, the intervention group compared with the control group reported higher increases in mean daily F/V servings (total: +2.0 vs. -0.4; P < 0.01), and nonsignificant decreases in the percentage of calories from fat (-2.2% vs. -1.1%; P = 0.69) and weight (-2.6 kg vs. -1.5 kg; P = 0.56). Compared with controls, participants in the intervention group had higher increases in plasma lutein (+20.4% vs. -11.5%; P < 0.01), and borderline significant increases in global DNA methylation (+0.8% vs. -0.5%; P = 0.06). The short-term ¡Cocinar Para Su Salud! program was effective at increasing long-term F/V intake in Hispanic breast cancer survivors and changed biomarkers associated with breast cancer recurrence risk. It is possible for short-term behavioral interventions to have long-term effects on behaviors and biomarkers in minority cancer patient populations. Results can inform future study designs. Cancer Epidemiol Biomarkers Prev; 25(11); 1491-502. ©2016 AACR. ©2016 American Association for Cancer Research.
Greenlee, Heather; Gaffney, Ann Ogden; Aycinena, A. Corina; Koch, Pam; Contento, Isobel; Karmally, Wahida; Richardson, John M.; Shi, Zaixing; Lim, Emerson; Tsai, Wei-Yann; Santella, Regina M.; Blaner, William S.; Clugston, Robin D.; Cremers, Serge; Pollak, Susan; Sirosh, Iryna; Crew, Katherine D.; Maurer, Matthew; Kalinsky, Kevin; Hershman, Dawn L.
2017-01-01
Background Among Hispanic breast cancer (BC) survivors, we examined the long-term effects of a short-term culturally-based dietary intervention on increasing fruits/vegetables (F/V), decreasing fat and changing biomarkers associated with BC recurrence risk. Methods Spanish-speaking women (n=70) with a history of stage 0-III BC who completed treatment were randomized to ¡Cocinar Para Su Salud! (n=34), a culturally-based 9-session program (24 hours over 12 weeks, including nutrition education, cooking classes, and food-shopping field trips), or a control group (n=36, written dietary recommendations for BC survivors). Diet recalls, fasting blood, and anthropometric measures were collected at baseline, 6, and 12 months. We report changes between groups at 12 months in dietary intake and biomarkers using 2-sample Wilcoxon t-tests and Generalized Estimating Equation (GEE) models. Results At 12 months, the intervention group compared to the control group reported higher increases in mean daily F/V servings (total: +2.0 vs. −0.4; P=0.006), and non-significant decreases in percent calories from fat (−2.2% vs. −1.1%; P=0.69) and weight (−2.6 kg vs. −1.5 kg; P=0.56). Compared to controls, participants in the intervention group had higher increases in plasma lutein (+20.4% vs. −11.5%; P=0.002), and borderline significant increases in global DNA methylation (+0.8% vs. −0.5%; P=0.06). Conclusions The short-term ¡Cocinar Para Su Salud! program was effective at increasing long-term F/V intake in Hispanic BC survivors and changed biomarkers associated with BC recurrence risk. Impact It is possible for short-term behavioral interventions to have long-term effects on behaviors and biomarkers in minority cancer patient populations. Results can inform future study designs. PMID:27461049
Endpoints in medical communication research, proposing a framework of functions and outcomes.
de Haes, Hanneke; Bensing, Jozien
2009-03-01
The evidence base of medical communication has been underdeveloped and the field was felt to be in need for thorough empirical investigation. Studying medical communication can help to clarify what happens during medical encounters and, subsequently, whether the behavior displayed is effective. However, before effectiveness can be established, one should argue what functions or goals the communication has and what outcomes are relevant in medical communication research. In the present paper, we first suggest the six function model of medical communication based on the integration of earlier models. The model distinguishes (1) fostering the relationship, (2) gathering information, (3) information provision, (4) decision making, (5) enabling disease and treatment-related behavior, and (6) responding to emotions. Secondly, a framework for endpoints in such research is presented. Immediate, intermediate and long-term outcomes are distinguished on the one hand and patient-, provider- and process- or context-related outcomes on the other. Based on this framework priorities can be defined and a tentative hierarchy proposed. Health is suggested to be the primary goal of medical communication as are patient-related outcomes. Dilemmas are described. Finally, in medical communication research, theory is advocated to link health care provider behavior or skills to outcomes and to connect intermediate outcomes to long-term ones. By linking specific communication elements to concrete endpoints within the six function model of medical communication, communication will become better integrated within the process of medical care. This is helpful to medical teachers and motivational to medical students. This approach can provide the place to medical communication it deserves in the center of medical care.
Hysteresis, regime shifts, and non-stationarity in aquifer recharge-storage-discharge systems
NASA Astrophysics Data System (ADS)
Klammler, Harald; Jawitz, James; Annable, Michael; Hatfield, Kirk; Rao, Suresh
2016-04-01
Based on physical principles and geological information we develop a parsimonious aquifer model for Silver Springs, one of the largest karst springs in Florida. The model structure is linear and time-invariant with recharge, aquifer head (storage) and spring discharge as dynamic variables at the springshed (landscape) scale. Aquifer recharge is the hydrological driver with trends over a range of time scales from seasonal to multi-decadal. The freshwater-saltwater interaction is considered as a dynamic storage mechanism. Model results and observed time series show that aquifer storage causes significant rate-dependent hysteretic behavior between aquifer recharge and discharge. This leads to variable discharge per unit recharge over time scales up to decades, which may be interpreted as a gradual and cyclic regime shift in the aquifer drainage behavior. Based on field observations, we further amend the aquifer model by assuming vegetation growth in the spring run to be inversely proportional to stream velocity and to hinder stream flow. This simple modification introduces non-linearity into the dynamic system, for which we investigate the occurrence of rate-independent hysteresis and of different possible steady states with respective regime shifts between them. Results may contribute towards explaining observed non-stationary behavior potentially due to hydrological regime shifts (e.g., triggered by gradual, long-term changes in recharge or single extreme events) or long-term hysteresis (e.g., caused by aquifer storage). This improved understanding of the springshed hydrologic response dynamics is fundamental for managing the ecological, economic and social aspects at the landscape scale.
Out-of-time-ordered correlators in a quantum Ising chain
NASA Astrophysics Data System (ADS)
Lin, Cheng-Ju; Motrunich, Olexei I.
2018-04-01
Out-of-time-ordered correlators (OTOC) have been proposed to characterize quantum chaos in generic systems. However, they can also show interesting behavior in integrable models, resembling the OTOC in chaotic systems in some aspects. Here we study the OTOC for different operators in the exactly-solvable one-dimensional quantum Ising spin chain. The OTOC for spin operators that are local in terms of the Jordan-Wigner fermions has a "shell-like" structure: After the wavefront passes, the OTOC approaches its original value in the long-time limit, showing no signature of scrambling; the approach is described by a t-1 power law at long time t . On the other hand, the OTOC for spin operators that are nonlocal in the Jordan-Wigner fermions has a "ball-like" structure, with its value reaching zero in the long-time limit, looking like a signature of scrambling; the approach to zero, however, is described by a slow power law t-1 /4 for the Ising model at the critical coupling. These long-time power-law behaviors in the lattice model are not captured by conformal field theory calculations. The mixed OTOC with both local and nonlocal operators in the Jordan-Wigner fermions also has a "ball-like" structure, but the limiting values and the decay behavior appear to be nonuniversal. In all cases, we are not able to define a parametrically large window around the wavefront to extract the Lyapunov exponent.
Identifying and treating agitated behaviors in the long-term care setting.
Hastings, S N; Thompson-Heisterman, A; Farrell, S P
1999-01-01
This article provides information on identification, assessment, and intervention techniques for agitated behaviors in the long-term care setting. Although the emphasis is on prevention and management of agitation, the article offers suggestions to assist health care providers in differentiating between delirium, psychosis, depression, anxiety, and dementia, which may place a resident at risk for agitation. Basic treatment approaches for each of these disorders is also reviewed.
Behavior Analysis of Forgiveness in Couples Therapy
ERIC Educational Resources Information Center
Cordova, James; Cautilli, Joseph; Simon, Corrina; Sabag, Robin Axelrod
2006-01-01
Behavioral couples' therapy has a long history of success with couples and is an empirically validated treatment for marital discord (Task Force on Promotion and Dissemination of Psychological Procedures, 1995). However, only about 50% of all couples in treatment experience long-term change (2 years). One of the founders of behavioral couples'…
Cepeda, Alice; Saint Onge, Jarron M.; Nowotny, Kathryn M.; Valdez, Avelardo
2018-01-01
Research has found that among juveniles weak ties to informal social control entities such as parents, school, and conventional peers increase the probability of the initiation and continuation of deviant behaviors such as drug use and crime. Given the weak ties of formal social control mechanisms in highly disadvantaged communities, informal social control mechanisms are often an important deterrent that reduce or moderate engagement in deviant behaviors among serious and persistent offenders. This analysis examines the association between long-term gang membership and adolescent informal social control processes, drug use, and delinquency. This research is based on data from a study of 160 Mexican American male gang members between the ages of 16 and 20. Findings suggest that among gang members in this context, commonly studied informal control mechanisms such as the family and schools do not function to deter long-term gang membership that is associated with serious criminal and violent behavior and drug use. The implications for future research on desistance or continuation of antisocial behavior across the life course are discussed. PMID:25979430
Younan, Diana; Tuvblad, Catherine; Franklin, Meredith; Lurmann, Fred; Li, Lianfa; Wu, Jun; Berhane, Kiros; Baker, Laura A; Chen, Jiu-Chiuan
2017-12-13
Animal experiments and cross-sectional human studies have linked particulate matter (PM) with increased behavioral problems. We conducted a longitudinal study to examine whether the trajectories of delinquent behavior are affected by PM 2.5 (PM with aerodynamic diameter ≤ 2.5 μm) exposures before and during adolescence. We used the parent-reported Child Behavior Checklist at age 9-18 with repeated measures every ~2-3 years (up to 4 behavioral assessments) on 682 children from the Risk Factors for Antisocial Behavior Study conducted in a multi-ethnic cohort of twins born in 1990-1995. Based on prospectively-collected residential addresses and a spatiotemporal model of ambient air concentrations in Southern California, monthly PM 2.5 estimates were aggregated to represent long-term (1-, 2-, 3-year average) exposures preceding baseline and cumulative average exposure until the last assessment. Multilevel mixed-effects models were used to examine the association between PM 2.5 exposure and individual trajectories of delinquent behavior, adjusting for within-family/within-individual correlations and potential confounders. We also examined whether psychosocial factors modified this association. The results sμggest that PM 2.5 exposure at baseline and cumulative exposure during follow-up was significantly associated (p < 0.05) with increased delinquent behavior. The estimated effect sizes (per interquartile increase of PM 2.5 by 3.12-5.18 μg/m 3 ) were equivalent to the difference in delinquency scores between adolescents who are 3.5-4 years apart in age. The adverse effect was stronger in families with unfavorable parent-to-child relationships, increased parental stress or maternal depressive symptoms. Overall, these findings sμggest long-term PM 2.5 exposure may increase delinquent behavior of urban-dwelling adolescents, with the resulting neurotoxic effect aggravated by psychosocial adversities.
Illa, Miriam; Eixarch, Elisenda; Batalle, Dafnis; Arbat-Plana, Ariadna; Muñoz-Moreno, Emma; Figueras, Francesc; Gratacos, Eduard
2013-01-01
Background Intrauterine growth restriction (IUGR) affects 5–10% of all newborns and is associated with increased risk of memory, attention and anxiety problems in late childhood and adolescence. The neurostructural correlates of long-term abnormal neurodevelopment associated with IUGR are unknown. Thus, the aim of this study was to provide a comprehensive description of the long-term functional and neurostructural correlates of abnormal neurodevelopment associated with IUGR in a near-term rabbit model (delivered at 30 days of gestation) and evaluate the development of quantitative imaging biomarkers of abnormal neurodevelopment based on diffusion magnetic resonance imaging (MRI) parameters and connectivity. Methodology At +70 postnatal days, 10 cases and 11 controls were functionally evaluated with the Open Field Behavioral Test which evaluates anxiety and attention and the Object Recognition Task that evaluates short-term memory and attention. Subsequently, brains were collected, fixed and a high resolution MRI was performed. Differences in diffusion parameters were analyzed by means of voxel-based and connectivity analysis measuring the number of fibers reconstructed within anxiety, attention and short-term memory networks over the total fibers. Principal Findings The results of the neurobehavioral and cognitive assessment showed a significant higher degree of anxiety, attention and memory problems in cases compared to controls in most of the variables explored. Voxel-based analysis (VBA) revealed significant differences between groups in multiple brain regions mainly in grey matter structures, whereas connectivity analysis demonstrated lower ratios of fibers within the networks in cases, reaching the statistical significance only in the left hemisphere for both networks. Finally, VBA and connectivity results were also correlated with functional outcome. Conclusions The rabbit model used reproduced long-term functional impairments and their neurostructural correlates of abnormal neurodevelopment associated with IUGR. The description of the pattern of microstructural changes underlying functional defects may help to develop biomarkers based in diffusion MRI and connectivity analysis. PMID:24143189
Illa, Miriam; Eixarch, Elisenda; Batalle, Dafnis; Arbat-Plana, Ariadna; Muñoz-Moreno, Emma; Figueras, Francesc; Gratacos, Eduard
2013-01-01
Intrauterine growth restriction (IUGR) affects 5-10% of all newborns and is associated with increased risk of memory, attention and anxiety problems in late childhood and adolescence. The neurostructural correlates of long-term abnormal neurodevelopment associated with IUGR are unknown. Thus, the aim of this study was to provide a comprehensive description of the long-term functional and neurostructural correlates of abnormal neurodevelopment associated with IUGR in a near-term rabbit model (delivered at 30 days of gestation) and evaluate the development of quantitative imaging biomarkers of abnormal neurodevelopment based on diffusion magnetic resonance imaging (MRI) parameters and connectivity. At +70 postnatal days, 10 cases and 11 controls were functionally evaluated with the Open Field Behavioral Test which evaluates anxiety and attention and the Object Recognition Task that evaluates short-term memory and attention. Subsequently, brains were collected, fixed and a high resolution MRI was performed. Differences in diffusion parameters were analyzed by means of voxel-based and connectivity analysis measuring the number of fibers reconstructed within anxiety, attention and short-term memory networks over the total fibers. The results of the neurobehavioral and cognitive assessment showed a significant higher degree of anxiety, attention and memory problems in cases compared to controls in most of the variables explored. Voxel-based analysis (VBA) revealed significant differences between groups in multiple brain regions mainly in grey matter structures, whereas connectivity analysis demonstrated lower ratios of fibers within the networks in cases, reaching the statistical significance only in the left hemisphere for both networks. Finally, VBA and connectivity results were also correlated with functional outcome. The rabbit model used reproduced long-term functional impairments and their neurostructural correlates of abnormal neurodevelopment associated with IUGR. The description of the pattern of microstructural changes underlying functional defects may help to develop biomarkers based in diffusion MRI and connectivity analysis.
NASA Astrophysics Data System (ADS)
Riva, Federico; Agliardi, Federico; Amitrano, David; Crosta, Giovanni B.
2017-04-01
Large mountain slopes in alpine environments undergo a complex long-term evolution from glacial to postglacial environments, through a transient period of paraglacial readjustment. During and after this transition, the interplay among rock strength, topographic relief, and morpho-climatic drivers varying in space and time can lead to the development of different types of slope instability, from sudden catastrophic failures to large, slow, long-lasting yet potentially catastrophic rockslides. Understanding the long-term evolution of large rock slopes requires accounting for the time-dependence of deglaciation unloading, permeability and fluid pressure distribution, displacements and failure mechanisms. In turn, this is related to a convincing description of rock mass damage processes and to their transition from a sub-critical (progressive failure) to a critical (catastrophic failure) character. Although mechanisms of damage occurrence in rocks have been extensively studied in the laboratory, the description of time-dependent damage under gravitational load and variable external actions remains difficult. In this perspective, starting from a time-dependent model conceived for laboratory rock deformation, we developed Dadyn-RS, a tool to simulate the long-term evolution of real, large rock slopes. Dadyn-RS is a 2D, FEM model programmed in Matlab, which combines damage and time-to-failure laws to reproduce both diffused damage and strain localization meanwhile tracking long-term slope displacements from primary to tertiary creep stages. We implemented in the model the ability to account for rock mass heterogeneity and property upscaling, time-dependent deglaciation, as well as damage-dependent fluid pressure occurrence and stress corrosion. We first tested DaDyn-RS performance on synthetic case studies, to investigate the effect of the different model parameters on the mechanisms and timing of long-term slope behavior. The model reproduces complex interactions between topography, deglaciation rate, mechanical properties and fluid pressure occurrence, resulting in different kinematics, damage patterns and timing of slope instabilities. We assessed the role of groundwater on slope damage and deformation mechanisms by introducing time-dependent pressure cycling within simulations. Then, we applied DaDyn-RS to real slopes located in the Italian Central Alps, affected by an active rockslide and a Deep Seated Gravitational Slope Deformation, respectively. From Last Glacial Maximum to present conditions, our model allows reproducing in an explicitly time-dependent framework the progressive development of damage-induced permeability, strain localization and shear band differentiation at different times between the Lateglacial period and the Mid-Holocene climatic transition. Different mechanisms and timings characterize different styles of slope deformations, consistently with available dating constraints. DaDyn-RS is able to account for different long-term slope dynamics, from slow creep to the delayed transition to fast-moving rockslides.
Chen, Chien-Yi; Noble-Haeusslein, Linda J; Ferriero, Donna; Semple, Bridgette D
2013-01-01
Traumatic brain injury in children commonly involves the frontal lobes and is associated with distinct structural and behavioral changes. Despite the clinical significance of injuries localized to this region during brain development, the mechanisms underlying secondary damage and long-term recovery are poorly understood. Here, we have characterized the first model of unilateral focal traumatic injury to the developing frontal lobe. Male C57Bl/6J mice at postnatal day (p)21, an age approximating a toddler-aged child, received a controlled cortical impact or sham surgery to the left frontal lobe and were euthanized 1 or 7 days later. A necrotic cavity and local inflammatory response were largely confined to the unilateral frontal lobe, dorsal corpus callosum and striatum anterior to the bregma. While cell death and accumulated β-amyloid precursor protein were characteristic features of the pericontusional motor cortex, corpus callosum, cingulum and dorsal striatum, underlying structures including the hippocampus showed no overt pathology. To determine the long-term functional consequences of injury at p21, two additional cohorts were subjected to a battery of behavioral tests in adolescence (p35-45) or adulthood (p70-80). In both cohorts, brain-injured mice showed normal levels of anxiety, sociability, spatial learning and memory. The signature phenotypic features were deficits in motor function and motor learning, coincident with a reduction in ipsilateral cortical brain volumes. Together, these findings demonstrate classic morphological features of a focal traumatic injury, including early cell death and axonal injury, and long-term volumetric loss of cortical volumes. The presence of deficits in sensorimotor function and coordination in the absence of abnormal findings related to anxiety, sociability and memory likely reflects several variables, including the unique location of the injury and the emergence of favorable compensatory mechanisms during subsequent brain development. © 2013 S. Karger AG, Basel.
Chen, Chien-Yi; Noble-Haeusslein, Linda J; Ferriero, Donna; Semple, Bridgette D
2014-01-01
Traumatic brain injury in children commonly involves the frontal lobes, and is associated with distinct structural and behavioral changes. Despite the clinical significance of injuries localized to this region during brain development, the mechanisms underlying secondary damage and long-term recovery are poorly understood. Here we have characterized the first model of unilateral focal traumatic injury to the developing frontal lobe. Male C57Bl/6J mice at postnatal day (p) 21, an age approximating a toddler-aged child, received a controlled cortical impact or sham surgery to the left frontal lobe and were euthanized 1 and 7 d later. A necrotic cavity and local inflammatory response were largely confined to the unilateral frontal lobe, dorsal corpus callosum and striatum anterior to Bregma. While cell death and accumulated beta-amyloid precursor protein were characteristic features of the peri-contusional motor cortex, corpus callosum, cingulum and dorsal striatum, underlying structures including the hippocampus showed no overt pathology. To determine the long-term functional consequences of injury at p21, two additional cohorts were subjected to a battery of behavioral tests in adolescence (p35-45) or adulthood (p70-80). In both cohorts, brain-injured mice showed normal levels of anxiety, sociability, spatial learning and memory. The signature phenotypic features were deficits in motor function and motor learning, coincident with a reduction in ipsilateral cortical brain volumes. Together, these findings demonstrate classic morphological features of a focal traumatic injury, including early cell death and axonal injury, and long-term volumetric loss of cortical volumes. The presence of deficits in sensorimotor function and coordination in the absence of abnormal findings related to anxiety, sociability and memory, likely reflect several variables including the unique location of the injury and the emergence of favorable compensatory mechanisms during subsequent brain development. PMID:24247103
Creep rupture behavior of unidirectional advanced composites
NASA Technical Reports Server (NTRS)
Yeow, Y. T.
1980-01-01
A 'material modeling' methodology for predicting the creep rupture behavior of unidirectional advanced composites is proposed. In this approach the parameters (obtained from short-term tests) required to make the predictions are the three principal creep compliance master curves and their corresponding quasi-static strengths tested at room temperature (22 C). Using these parameters in conjunction with a failure criterion, creep rupture envelopes can be generated for any combination of in-plane loading conditions and ambient temperature. The analysis was validated experimentally for one composite system, the T300/934 graphite-epoxy system. This was done by performing short-term creep tests (to generate the principal creep compliance master curves with the time-temperature superposition principle) and relatively long-term creep rupture tensile tests of off-axis specimens at 180 C. Good to reasonable agreement between experimental and analytical results is observed.
Fukushima Daiichi Unit 1 Ex-Vessel Prediction: Core Concrete Interaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robb, Kevin R; Farmer, Mitchell; Francis, Matthew W
Lower head failure and corium concrete interaction were predicted to occur at Fukushima Daiichi Unit 1 (1F1) by several different system-level code analyses, including MELCOR v2.1 and MAAP5. Although these codes capture a wide range of accident phenomena, they do not contain detailed models for ex-vessel core melt behavior. However, specialized codes exist for analysis of ex-vessel melt spreading (e.g., MELTSPREAD) and long-term debris coolability (e.g., CORQUENCH). On this basis, an analysis was carried out to further evaluate ex-vessel behavior for 1F1 using MELTSPREAD and CORQUENCH. Best-estimate melt pour conditions predicted by MELCOR v2.1 and MAAP5 were used as input.more » MELTSPREAD was then used to predict the spatially dependent melt conditions and extent of spreading during relocation from the vessel. The results of the MELTSPREAD analysis are reported in a companion paper. This information was used as input for the long-term debris coolability analysis with CORQUENCH.« less
Fukushima Daiichi Unit 1 ex-vessel prediction: Core melt spreading
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farmer, M. T.; Robb, K. R.; Francis, M. W.
Lower head failure and corium-concrete interaction were predicted to occur at Fukushima Daiichi Unit 1 (1F1) by several different system-level code analyses, including MELCOR v2.1 and MAAP5. Although these codes capture a wide range of accident phenomena, they do not contain detailed models for ex-vessel core melt behavior. However, specialized codes exist for analysis of ex-vessel melt spreading (e.g., MELTSPREAD) and long-term debris coolability (e.g., CORQUENCH). On this basis, an analysis has been carried out to further evaluate ex-vessel behavior for 1F1 using MELTSPREAD and CORQUENCH. Best-estimate melt pour conditions predicted by MELCOR v2.1 and MAAP5 were used as input.more » MELTSPREAD was then used to predict the spatially-dependent melt conditions and extent of spreading during relocation from the vessel. Lastly, this information was then used as input for the long-term debris coolability analysis with CORQUENCH that is reported in a companion paper.« less
Zbar, Ariella; Surkan, Pamela J; Fombonne, Eric; Melchior, Maria
2016-10-01
Children who experience behavioral difficulties often have short and long-term school problems. However, the relationship between emotional difficulties and later academic achievement has not been thoroughly examined. Using data from the French TEMPO study (n = 666, follow-up 1991, 1999, 2009, mean age = 10.5, sd = 4.9 at baseline), we studied associations between internalizing and externalizing symptoms in: (a) childhood and (b) adolescence and educational attainment by young adulthood (< vs. ≥ high school degree), accounting for participants' age, sex, juvenile academic difficulties, and family income. High levels of childhood (but not adolescent) internalizing and externalizing symptoms were associated with low educational attainment; however, in multivariate models only the association with childhood internalizing symptoms remained statistically significant (OR = 1.75, 95 % CI 1.00-3.02). Supporting children with internalizing problems early on could help improve their long-term educational attainment.
Fukushima Daiichi Unit 1 ex-vessel prediction: Core melt spreading
Farmer, M. T.; Robb, K. R.; Francis, M. W.
2016-10-31
Lower head failure and corium-concrete interaction were predicted to occur at Fukushima Daiichi Unit 1 (1F1) by several different system-level code analyses, including MELCOR v2.1 and MAAP5. Although these codes capture a wide range of accident phenomena, they do not contain detailed models for ex-vessel core melt behavior. However, specialized codes exist for analysis of ex-vessel melt spreading (e.g., MELTSPREAD) and long-term debris coolability (e.g., CORQUENCH). On this basis, an analysis has been carried out to further evaluate ex-vessel behavior for 1F1 using MELTSPREAD and CORQUENCH. Best-estimate melt pour conditions predicted by MELCOR v2.1 and MAAP5 were used as input.more » MELTSPREAD was then used to predict the spatially-dependent melt conditions and extent of spreading during relocation from the vessel. Lastly, this information was then used as input for the long-term debris coolability analysis with CORQUENCH that is reported in a companion paper.« less
Zimmer, Aline Rigon; Leonardi, Bianca; Kalinine, Eduardo; de Souza, Diogo Onofre; Portela, Luis Valmor; Gosmann, Grace
2012-01-01
Our group showed that crude ethanol (CE) and butanol (BUT) extracts of Capsicum baccatum presented anti-inflammatory and antioxidant properties. Furthermore, the flavonoid and total phenolic contents were positively correlated with both of these properties observed for C. baccatum extracts. The present study demonstrated that 60 days of oral administration of CE and BUT (200 mg/kg) in mice did not cause significant differences in the following parameters evaluated: hematological profile, body weight and relative weight of visceral organs, systemic lipid profile, glucose homeostasis (GTT), kidney and hepatic biochemical markers, and spontaneous locomotion and anxiety-like behavior. Altogether, these results indicate for the first time that the long-term oral administration of C. baccatum extracts does not affect specific aspects of CF1 mice physiology, suggesting their safety, building up the venue to test their efficacy in animal models underlying persistent activation of oxidative and inflammatory pathways. PMID:23320023
Simulation of Long-Term Landscape-Level Fuel Treatment Effects on Large Wildfires
Mark A. Finney; Rob C. Seli; Charles W. McHugh; Alan A. Ager; Berni Bahro; James K. Agee
2006-01-01
A simulation system was developed to explore how fuel treatments placed in random and optimal spatial patterns affect the growth and behavior of large fires when implemented at different rates over the course of five decades. The system consists of a forest/fuel dynamics simulation module (FVS), logic for deriving fuel model dynamics from FVS output, a spatial fuel...
Ancient Chinese Observations and Modern Cometary Models
NASA Technical Reports Server (NTRS)
Yeomans, D. K.
1995-01-01
Ancient astronomical observations, primarily by Chinese, represent the only data source for discerning the long-term behavior of comets. These sky watchers produced astrological forecasts for their emperors. The comets Halley, Swift-Tuttle, and Tempel-Tuttle have been observed for 2000 years. Records of the Leonid meteor showers, starting from A.D.902, are used to guide predictions for the 1998-1999 reoccurrence.
ERIC Educational Resources Information Center
Adamo, Elyse K.; Wu, Jenny; Wolery, Mark; Hemmeter, Mary Louise; Ledford, Jennifer R.; Barton, Erin E.
2015-01-01
Children with Down syndrome may be at increased risk of problems associated with inactivity. Early intervention to increase physical activity may lead to increased participation in typical activities and long-term increases in quality of life (e.g., decreased likelihood of obesity-related illness). A multi-component intervention, including video…
ERIC Educational Resources Information Center
Lee, Madeline Y.; Danna, Laura; Walker, Douglas W.
2017-01-01
The long-term nature of mental health needs after disasters, such as Hurricane Katrina, continues to require attention. Research that emerged during the anniversaries of the storm has shown Katrina and its aftermath to be associated with posttraumatic stress, depression, anxiety, disruptive behavior, and somatic complaints in children and…
Thermoelectric properties of 80 a/o Si-20 a/o Ge alloy
NASA Technical Reports Server (NTRS)
Raag, V.
1974-01-01
This paper discusses the time and temperature dependence of the thermoelectric properties of n- and p-type 80 at. % Si-20 at. % Ge alloy. It is shown that the time-temperature behavior of the properties of both polarity types of this alloy can be described by means of a diffusion-limited dopant precipitation model due to Lifshitz and Slyozov (1961). An experimental program for the determination of the long-term behavior of the properties of the alloy is described in terms of the Lifshitz-Slyozov model, and the thermoelectric properties of the alloy are given for temperatures in the range from room temperature to 1000 C as a function of time up to and including twelve years. The data given for the p-type alloy represent the first time-dependent thermoelectric property data ever published for the p-type silicon-germanium alloys.
Predictive aging results for cable materials in nuclear power plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gillen, K.T.; Clough, R.L.
1990-11-01
In this report, we provide a detailed discussion of methodology of predicting cable degradation versus dose rate, temperature, and exposure time and its application to data obtained on a number of additional nuclear power plant cable insulation (a hypalon, a silicon rubber and two ethylenetetrafluoroethylenes) and jacket (a hypalon) materials. We then show that the predicted, low-dose-rate results for our materials are in excellent agreement with long-term (7 to 9 years), low dose-rate results recently obtained for the same material types actually aged under nuclear power plant conditions. Based on a combination of the modelling and long-term results, we findmore » indications of reasonably similar degradation responses among several different commercial formulations for each of the following generic'' materials: hypalon, ethylenetetrafluoroethylene, silicone rubber and PVC. If such generic'' behavior can be further substantiated through modelling and long-term results on additional formulations, predictions of cable life for other commercial materials of the same generic types would be greatly facilitated. Finally, to aid utilities in their cable life extension decisions, we utilize our modelling results to generate lifetime prediction curves for the materials modelled to data. These curves plot expected material lifetime versus dose rate and temperature down to the levels of interest to nuclear power plant aging. 18 refs., 30 figs., 3 tabs.« less
NASA Astrophysics Data System (ADS)
Fischer, T.; Matyska, C.; Heinicke, J.
2017-02-01
The West Bohemia/Vogtland region is characterized by earthquake swarm activity and degassing of CO2 of mantle origin. A fast increase of CO2 flow rate was observed 4 days after a ML 3.5 earthquake in May 2014 in the Hartoušov mofette, 9 km from the epicentres. During the subsequent 150 days the flow reached sixfold of the original level, and has been slowly decaying until present. Similar behavior was observed during and after the swarm in 2008 pointing to a fault-valve mechanism in long-term. Here, we present the results of simulation of gas flow in a two dimensional model of Earth's crust composed of a sealing layer at the hypocentre depth which is penetrated by the earthquake fault and releases fluid from a relatively low-permeability lower crust. This simple model is capable of explaining the observations, including the short travel time of the flow pulse from 8 km depth to the surface, long-term flow increase and its subsequent slow decay. Our model is consistent with other analyse of the 2014 aftershocks which attributes their anomalous character to exponentially decreasing external fluid force. Our observations and model hence track the fluid pressure pulse from depth where it was responsible for aftershocks triggering to the surface where a significant long-term increase of CO2 flow started 4 days later.
Nomura, Toshihiro; Oyamada, Yoshihiro; Fernandes, Herman B.; Remmers, Christine; Xu, Jian; Meltzer, Herbert; Contractor, Anis
2015-01-01
Repeated administration of non-competitive N-methyl-d-aspartate (NMDA) receptor antagonists such as phencyclidine (PCP) to rodents causes long-lasting deficits in cognition and memory, and has effects on behaviors that have been suggested to be models of the cognitive impairment associated with schizophrenia (CIAS). Despite this being a widely studied animal model, little is known about the long lasting changes in synapses and circuits that underlie the altered behaviors. Here we examined synaptic transmission ex-vivo in the hippocampus of mice after a subchronic PCP (scPCP) administration regime. We found that after at least one week of drug free washout period when mice have impaired cognitive function, the threshold for long term potentiation (LTP) of CA1 excitatory synapses was elevated. This elevated LTP threshold was directly related to increased inhibitory input to CA1 pyramidal cells through increased activity of GABAergic neurons. These results suggest repeated PCP administration causes a long-lasting metaplastic change in the inhibitory circuits in the hippocampus that results in impaired LTP, and could contribute to the deficits in hippocampal-dependent memory in PCP-treated mice. Changes in GABA signaling have been described in patients with schizophrenia, therefore our results support using scPCP as a model of CIAS. PMID:25937215
Doroudchi, M Mehdi; Greenberg, Kenneth P; Liu, Jianwen; Silka, Kimberly A; Boyden, Edward S; Lockridge, Jennifer A; Arman, A Cyrus; Janani, Ramesh; Boye, Shannon E; Boye, Sanford L; Gordon, Gabriel M; Matteo, Benjamin C; Sampath, Alapakkam P; Hauswirth, William W; Horsager, Alan
2011-01-01
Previous work established retinal expression of channelrhodopsin-2 (ChR2), an algal cation channel gated by light, restored physiological and behavioral visual responses in otherwise blind rd1 mice. However, a viable ChR2-based human therapy must meet several key criteria: (i) ChR2 expression must be targeted, robust, and long-term, (ii) ChR2 must provide long-term and continuous therapeutic efficacy, and (iii) both viral vector delivery and ChR2 expression must be safe. Here, we demonstrate the development of a clinically relevant therapy for late stage retinal degeneration using ChR2. We achieved specific and stable expression of ChR2 in ON bipolar cells using a recombinant adeno-associated viral vector (rAAV) packaged in a tyrosine-mutated capsid. Targeted expression led to ChR2-driven electrophysiological ON responses in postsynaptic retinal ganglion cells and significant improvement in visually guided behavior for multiple models of blindness up to 10 months postinjection. Light levels to elicit visually guided behavioral responses were within the physiological range of cone photoreceptors. Finally, chronic ChR2 expression was nontoxic, with transgene biodistribution limited to the eye. No measurable immune or inflammatory response was observed following intraocular vector administration. Together, these data indicate that virally delivered ChR2 can provide a viable and efficacious clinical therapy for photoreceptor disease-related blindness. PMID:21505421
An expectancy-value theory approach to the long-term modification of smoking behavior.
Rogers, R W; Deckner, C W; Mewborn, C R
1978-04-01
Despite the research interest in modifying smoking behavior, therapeutic treatments that can produce long-term cessation have not been demonstrated rigorously. A follow-up study of two attitude change experiments (N = 173) examined the effects of a fear appeal, that is, increasing smokers' awareness and appreciation of the highly noxious consequences of smoking. Although this familiar type of information may be an integral component of many smoking treatment programs, its long-term suppressive effect has not been demonstrated in well-controlled experiments. The results disclosed that 3 months and also 1 year after treatment, a high-fear manipulation had increased significantly the percentage of smokers who were able to stop smoking completely.
Anomalous Fluctuations in Autoregressive Models with Long-Term Memory
NASA Astrophysics Data System (ADS)
Sakaguchi, Hidetsugu; Honjo, Haruo
2015-10-01
An autoregressive model with a power-law type memory kernel is studied as a stochastic process that exhibits a self-affine-fractal-like behavior for a small time scale. We find numerically that the root-mean-square displacement Δ(m) for the time interval m increases with a power law as mα with α < 1/2 for small m but saturates at sufficiently large m. The exponent α changes with the power exponent of the memory kernel.
International Space Station Human Behavior and Performance Competency Model: Volume I
NASA Technical Reports Server (NTRS)
Schmidt, Lacey
2008-01-01
This document defines Human Behavior and Performance (HBP) competencies that are recommended to be included as requirements to participate in international long duration missions. They were developed in response to the Multilateral Crew Operations Panel (MMOP) request to develop HBP training requirements for the International Space Station (ISS). The competency model presented here was developed by the ITCB HBPT WG and forms the basis for determining the HBP training curriculum for long duration crewmembers. This document lists specific HBP competencies and behaviors required of astronauts/cosmonauts who participate in ISS expedition and other international longduration missions. Please note that this model does not encompass all competencies required. For example, outside the scope of this document are cognitive skills and abilities, including but not limited to concentration, memorization, perception, imagination, and thinking. It is assumed that these skills, which are crucial in terms of human behavior and performance, are considered during selection phase since such professionally significant qualities of the operator should be taken into consideration in order to ensure sufficient baseline levels that can be further improved during general astronaut training. Also, technical competencies, even though critical for crewmembers, are beyond the scope of this document. It should also be noted that the competencies in this model (and subsequent objectives) are not intended to limit the internal activities or training programs of any international partner.
A Descriptive, Multiyear Examination of Positive Behavior Support
ERIC Educational Resources Information Center
Dunlap, Glen; Carr, Edward G.; Horner, Robert H.; Koegel, Robert L.; Sailor, Wayne; Clarke, Shelley; Koegel, Lynn Kern; Albin, Richard W.; Vaughn, Bobbie J.; McLaughlin, Darlene Magito; James, Kim Mullen; Todd, Anne W.; Newton, J. Stephen; Lucyshyn, Joseph; Griggs, Peter; Bohanon, Hank; Choi, Jeong Hoon; Vismara, Laurie; Minjarez, Mendy Boettcher; Buschbacher, Pamelazita; Fox, Lise
2010-01-01
A major goal of positive behavior support (PBS) is to produce broad-based, long-term improvements in adaptive behavior; however, the empirical base, at present, is mainly composed of relatively short-term studies carried out in circumscribed contexts. Therefore, a need exists for reliable data that can inform the field regarding the comprehensive…
A neural network model of memory and higher cognitive functions.
Vogel, David D
2005-01-01
I first describe a neural network model of associative memory in a small region of the brain. The model depends, unconventionally, on disinhibition of inhibitory links between excitatory neurons rather than long-term potentiation (LTP) of excitatory projections. The model may be shown to have advantages over traditional neural network models both in terms of information storage capacity and biological plausibility. The learning and recall algorithms are independent of network architecture, and require no thresholds or finely graded synaptic strengths. Several copies of this local network are then connected by means of many, weak, reciprocal, excitatory projections that allow one region to control the recall of information in another to produce behaviors analogous to serial memory, classical and operant conditioning, secondary reinforcement, refabrication of memory, and fabrication of possible future events. The network distinguishes between perceived and recalled events, and can predicate its response on the absence as well as the presence of particular stimuli. Some of these behaviors are achieved in ways that seem to provide instances of self-awareness and imagination, suggesting that consciousness may emerge as an epiphenomenon in simple brains.
Blaeser, Frank; Sanders, Matthew J; Truong, Nga; Ko, Shanelle; Wu, Long Jun; Wozniak, David F; Fanselow, Michael S; Zhuo, Min; Chatila, Talal A
2006-12-01
Signaling by the Ca(2+)/calmodulin kinase (CaMK) cascade has been implicated in neuronal gene transcription, synaptic plasticity, and long-term memory consolidation. The CaM kinase kinase alpha (CaMKKalpha) isoform is an upstream component of the CaMK cascade whose function in different behavioral and learning and memory paradigms was analyzed by targeted gene disruption in mice. CaMKKalpha mutants exhibited normal long-term spatial memory formation and cued fear conditioning but showed deficits in context fear during both conditioning and long-term follow-up testing. They also exhibited impaired activation of the downstream kinase CaMKIV/Gr and its substrate, the transcription factor cyclic AMP-responsive element binding protein (CREB) upon fear conditioning. Unlike CaMKIV/Gr-deficient mice, the CaMKKalpha mutants exhibited normal long-term potentiation and normal levels of anxiety-like behavior. These results demonstrate a selective role for CaMKKalpha in contextual fear memory and suggest that different combinations of upstream and downstream components of the CaMK cascade may serve distinct physiological functions.
Chaos and unpredictability in evolution.
Doebeli, Michael; Ispolatov, Iaroslav
2014-05-01
The possibility of complicated dynamic behavior driven by nonlinear feedbacks in dynamical systems has revolutionized science in the latter part of the last century. Yet despite examples of complicated frequency dynamics, the possibility of long-term evolutionary chaos is rarely considered. The concept of "survival of the fittest" is central to much evolutionary thinking and embodies a perspective of evolution as a directional optimization process exhibiting simple, predictable dynamics. This perspective is adequate for simple scenarios, when frequency-independent selection acts on scalar phenotypes. However, in most organisms many phenotypic properties combine in complicated ways to determine ecological interactions, and hence frequency-dependent selection. Therefore, it is natural to consider models for evolutionary dynamics generated by frequency-dependent selection acting simultaneously on many different phenotypes. Here we show that complicated, chaotic dynamics of long-term evolutionary trajectories in phenotype space is very common in a large class of such models when the dimension of phenotype space is large, and when there are selective interactions between the phenotypic components. Our results suggest that the perspective of evolution as a process with simple, predictable dynamics covers only a small fragment of long-term evolution. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.
López-Granero, Caridad; Cardona, Diana; Giménez, Estela; Lozano, Rafael; Barril, José; Aschner, Michael; Sánchez-Santed, Fernando; Cañadas, Fernando
2014-01-01
Organophosphates (OPs) affect behavior by inhibiting acetylcholinesterase (AChE). While the cognitive short-term effects may be directly attributed to this inhibition, the mechanisms that underlie OP's long-term cognitive effects remain controversial and poorly understood. Accordingly, two experiments were designed to assess the effects of OPs on cognition, and to ascertain whether both the short- and long-term effects of are AChE-dependent. A single subcutaneous dose of 250 mg/kg chlorpyrifos (CPF), 1.5mg/kg diisopropylphosphorofluoridate (DFP) or 15 mg/kg parathion (PTN) was administered to male Wistar rats. Spatial learning was evaluated 72 h or 23 weeks after exposure, and impulsive choice was tested at 10 and 30 weeks following OPs administration (experiment 1 and 2, respectively). Brain soluble and membrane-bound AChE activity, synaptic AChE-S mRNA, read-through AChE-R mRNA and brain acylpeptide hydrolase (APH) activity (as alternative non-cholinergic target) were analyzed upon completion of the behavioral testing (17 and 37 weeks after OPs exposure). Both short- and long-term CPF treatment caused statistically significant effects on spatial learning, while PTN treatment led only to statistically significant short-term effects. Neither CPF, DFP nor PTN affected the long-term impulsivity response. Long-term exposure to CPF and DFP significantly decreased AChE-S and AChE-R mRNA, while in the PTN treated group only AChE-S mRNA levels were decreased. However, after long-term OP exposure, soluble and membrane-bound AChE activity was indistinguishable from controls. Finally, no changes were noted in brain APH activity in response to OP treatment. Taken together, this study demonstrates long-term effects of OPs on AChE-S and AChE-R mRNA in the absence of changes in AChE soluble and membrane-bound activity. Thus, changes in AChE mRNA expression imply non-catalytic properties of the AChE enzyme. Copyright © 2013 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Messner, M. C.; Truster, T. J.; Cochran, K. B.
Advanced reactors designed to operate at higher temperatures than current light water reactors require structural materials with high creep strength and creep-fatigue resistance to achieve long design lives. Grade 91 is a ferritic/martensitic steel designed for long creep life at elevated temperatures. It has been selected as a candidate material for sodium fast reactor intermediate heat exchangers and other advanced reactor structural components. This report focuses on the creep deformation and rupture life of Grade 91 steel. The time required to complete an experiment limits the availability of long-life creep data for Grade 91 and other structural materials. Design methodsmore » often extrapolate the available shorter-term experimental data to longer design lives. However, extrapolation methods tacitly assume the underlying material mechanisms causing creep for long-life/low-stress conditions are the same as the mechanisms controlling creep in the short-life/high-stress experiments. A change in mechanism for long-term creep could cause design methods based on extrapolation to be non-conservative. The goal for physically-based microstructural models is to accurately predict material response in experimentally-inaccessible regions of design space. An accurate physically-based model for creep represents all the material mechanisms that contribute to creep deformation and damage and predicts the relative influence of each mechanism, which changes with loading conditions. Ideally, the individual mechanism models adhere to the material physics and not an empirical calibration to experimental data and so the model remains predictive for a wider range of loading conditions. This report describes such a physically-based microstructural model for Grade 91 at 600° C. The model explicitly represents competing dislocation and diffusional mechanisms in both the grain bulk and grain boundaries. The model accurately recovers the available experimental creep curves at higher stresses and the limited experimental data at lower stresses, predominately primary creep rates. The current model considers only one temperature. However, because the model parameters are, for the most part, directly related to the physics of fundamental material processes, the temperature dependence of the properties are known. Therefore, temperature dependence can be included in the model with limited additional effort. The model predicts a mechanism shift for 600° C at approximately 100 MPa from a dislocation- dominated regime at higher stress to a diffusion-dominated regime at lower stress. This mechanism shift impacts the creep life, notch-sensitivity, and, likely, creep ductility of Grade 91. In particular, the model predicts existing extrapolation methods for creep life may be non-conservative when attempting to extrapolate data for higher stress creep tests to low stress, long-life conditions. Furthermore, the model predicts a transition from notchstrengthening behavior at high stress to notch-weakening behavior at lower stresses. Both behaviors may affect the conservatism of existing design methods.« less
Supplementation of Korean Red Ginseng improves behavior deviations in animal models of autism
Gonzales, Edson Luck T.; Jang, Jong-Hwa; Mabunga, Darine Froy N.; Kim, Ji-Woon; Ko, Mee Jung; Cho, Kyu Suk; Bahn, Geon Ho; Hong, Minha; Ryu, Jong Hoon; Kim, Hee Jin; Cheong, Jae Hoon; Shin, Chan Young
2016-01-01
Background Autism spectrum disorder (ASD) is heterogeneous neurodevelopmental disorders that primarily display social and communication impairments and restricted/repetitive behaviors. ASD prevalence has increased in recent years, yet very limited therapeutic targets and treatments are available to counteract the incapacitating disorder. Korean Red Ginseng (KRG) is a popular herbal plant in South Korea known for its wide range of therapeutic effects and nutritional benefits and has recently been gaining great scientific attention, particularly for its positive effects in the central nervous system. Objectives Thus, in this study, we investigated the therapeutic potential of KRG in alleviating the neurobehavioral deficits found in the valproic acid (VPA)-exposed mice models of ASD. Design Starting at 21 days old (P21), VPA-exposed mice were given daily oral administrations of KRG solution (100 or 200 mg/kg) until the termination of all experiments. From P28, mice behaviors were assessed in terms of social interaction capacity (P28–29), locomotor activity (P30), repetitive behaviors (P32), short-term spatial working memory (P34), motor coordination (P36), and seizure susceptibility (P38). Results VPA-exposed mice showed sociability and social novelty preference deficits, hyperactivity, increased repetitive behavior, impaired spatial working memory, slightly affected motor coordination, and high seizure susceptibility. Remarkably, long-term KRG treatment in both dosages normalized all the ASD-related behaviors in VPA-exposed mice, except motor coordination ability. Conclusion As a food and herbal supplement with various known benefits, KRG demonstrated its therapeutic potential in rescuing abnormal behaviors related to autism caused by prenatal environmental exposure to VPA. PMID:26837496
Long-Term Post-CABG Survival: Performance of Clinical Risk Models Versus Actuarial Predictions.
Carr, Brendan M; Romeiser, Jamie; Ruan, Joyce; Gupta, Sandeep; Seifert, Frank C; Zhu, Wei; Shroyer, A Laurie
2016-01-01
Clinical risk models are commonly used to predict short-term coronary artery bypass grafting (CABG) mortality but are less commonly used to predict long-term mortality. The added value of long-term mortality clinical risk models over traditional actuarial models has not been evaluated. To address this, the predictive performance of a long-term clinical risk model was compared with that of an actuarial model to identify the clinical variable(s) most responsible for any differences observed. Long-term mortality for 1028 CABG patients was estimated using the Hannan New York State clinical risk model and an actuarial model (based on age, gender, and race/ethnicity). Vital status was assessed using the Social Security Death Index. Observed/expected (O/E) ratios were calculated, and the models' predictive performances were compared using a nested c-index approach. Linear regression analyses identified the subgroup of risk factors driving the differences observed. Mortality rates were 3%, 9%, and 17% at one-, three-, and five years, respectively (median follow-up: five years). The clinical risk model provided more accurate predictions. Greater divergence between model estimates occurred with increasing long-term mortality risk, with baseline renal dysfunction identified as a particularly important driver of these differences. Long-term mortality clinical risk models provide enhanced predictive power compared to actuarial models. Using the Hannan risk model, a patient's long-term mortality risk can be accurately assessed and subgroups of higher-risk patients can be identified for enhanced follow-up care. More research appears warranted to refine long-term CABG clinical risk models. © 2015 The Authors. Journal of Cardiac Surgery Published by Wiley Periodicals, Inc.
ERIC Educational Resources Information Center
Jones, Stephanie M.; Zhai, Fuhua; Raver, C. Cybele
2010-01-01
This paper investigates the long-term impact of participation in the Chicago School Readiness Project (CSRP) during the Head Start year on children's behavioral outcomes at the end of their Kindergarten year. The primary questions addressed in the paper are: (1) What is the experimental impact of CSRP on two-year change (from Fall Head Start to…
Schlarb, Angelika A; Bihlmaier, Isabel; Velten-Schurian, Kerstin; Poets, Christian F; Hautzinger, Martin
2018-01-01
This intervention study evaluates the short- and long-term effects of cognitive behavior therapy for insomnia (CBT-I) in groups for school-age children and their parents, named the KiSS-program. CBT-I was implemented in three sessions for children and three sessions for parents. All in all, 112 children with chronic childhood insomnia were randomly assigned to a wait-list (WL) control or treatment condition. According to subjective measures as well as objective wrist actigraphy, children in the CBT-I condition reported greater improvements in sleep behavior immediately after the treatment compared to the WL group. Improvements in sleep behavior after CBT-I persisted over the 3-, 6-, and 12-month follow-up assessments. The present study is the first randomized controlled trial that provides evidence for the long-term effectiveness of CBT-I in treating school-age children with chronic insomnia.
Henriques-Alves, Aron M.; Queiroz, Claudio M.
2016-01-01
In rodents, repeated exposure to unavoidable aggression followed by sustained sensory treat can lead to prolonged social aversion. The chronic social defeat stress model explores that phenomenon and it has been used as an animal model for human depression. However, some authors have questioned whether confounding effects may arise as the model also boosts anxiety-related behaviors. Despite its wide acceptance, most studies extract limited information from the behavior of the defeated animal. Often, the normalized occupancy around the social stimulus, the interaction zone, is taken as an index of depression. We hypothesized that this parameter is insufficient to fully characterize the behavioral consequences of this form of stress. Using an ethological approach, we showed that repeated social defeat delayed the expression of social investigation in long (10 min) sessions of social interaction. Also, the incidence of defensive behaviors, including stretched-attend posture and high speed retreats, was significantly higher in defeated mice in comparison to controls. Interestingly, a subpopulation of defeated mice showed recurrent and non-habituating stretched-attend posture and persistent flights during the entire session. Two indexes were created based on defensive behaviors to show that only recurrent flights correlates with sucrose intake. Together, the present study corroborates the idea that this model of social stress can precipitate a myriad of behaviors not readily disentangled. We propose that long sessions (>150 s) and detailed ethological evaluation during social interaction tests are necessary to provide enough information to correctly classify defeated animals in terms of resilience and susceptibility to social defeat stress. PMID:26869895
Henriques-Alves, Aron M; Queiroz, Claudio M
2015-01-01
In rodents, repeated exposure to unavoidable aggression followed by sustained sensory treat can lead to prolonged social aversion. The chronic social defeat stress model explores that phenomenon and it has been used as an animal model for human depression. However, some authors have questioned whether confounding effects may arise as the model also boosts anxiety-related behaviors. Despite its wide acceptance, most studies extract limited information from the behavior of the defeated animal. Often, the normalized occupancy around the social stimulus, the interaction zone, is taken as an index of depression. We hypothesized that this parameter is insufficient to fully characterize the behavioral consequences of this form of stress. Using an ethological approach, we showed that repeated social defeat delayed the expression of social investigation in long (10 min) sessions of social interaction. Also, the incidence of defensive behaviors, including stretched-attend posture and high speed retreats, was significantly higher in defeated mice in comparison to controls. Interestingly, a subpopulation of defeated mice showed recurrent and non-habituating stretched-attend posture and persistent flights during the entire session. Two indexes were created based on defensive behaviors to show that only recurrent flights correlates with sucrose intake. Together, the present study corroborates the idea that this model of social stress can precipitate a myriad of behaviors not readily disentangled. We propose that long sessions (>150 s) and detailed ethological evaluation during social interaction tests are necessary to provide enough information to correctly classify defeated animals in terms of resilience and susceptibility to social defeat stress.
NASA Astrophysics Data System (ADS)
Kembro, Jackelyn M.; Flesia, Ana Georgina; Gleiser, Raquel M.; Perillo, María A.; Marin, Raul H.
2013-12-01
Detrended Fluctuation Analysis (DFA) is a method that has been frequently used to determine the presence of long-range correlations in human and animal behaviors. However, according to previous authors using statistical model systems, in order to correctly use DFA different aspects should be taken into account such as: (1) the establishment by hypothesis testing of the absence of short term correlation, (2) an accurate estimation of a straight line in the log-log plot of the fluctuation function, (3) the elimination of artificial crossovers in the fluctuation function, and (4) the length of the time series. Taking into consideration these factors, herein we evaluated the presence of long-range correlation in the temporal pattern of locomotor activity of Japanese quail (Coturnix coturnix) and mosquito larva (Culex quinquefasciatus). In our study, modeling the data with the general autoregressive integrated moving average (ARFIMA) model, we rejected the hypothesis of short-range correlations (d=0) in all cases. We also observed that DFA was able to distinguish between the artificial crossover observed in the temporal pattern of locomotion of Japanese quail and the crossovers in the correlation behavior observed in mosquito larvae locomotion. Although the test duration can slightly influence the parameter estimation, no qualitative differences were observed between different test durations.
[Role of long-term potentiation in mechanism of the conditioned learning].
Tsvetkov, E A; Suderevskaia, E I; Veselkin, N P
2011-01-01
The review analyzes the fundamental problem of study of the neuronal mechanisms underlying processes of learning and memory. As a neuronal models of these phenomena there was considered one of the cellular phenomena that has characteristics similar with those in the process of "remembering"--such as the long-term potentiation (LTP). LTP is easily reproduced in certain synapses of the central nervous system, specifically in synapses of hippocampus and amygdala. As to the behavioral model of learning, there was used the conditioned learning, in frames of which production of the context-dependent/independent conditioned reaction was considered. Analysis of literature data has allowed showing that various stages of LTP produced on synapses of hippocampus or amygdala can be comparable with certain phase of the process of learning. Based on the exposed material the authors conclude that plastic changes of synapses of hippocampus and amygdala can represent the morphological substrate of some kinds of learning and memory.
Stationarity: Wanted dead or alive?
Lins, H.F.; Cohn, T.A.
2011-01-01
Aligning engineering practice with natural process behavior would appear, on its face, to be a prudent and reasonable course of action. However, if we do not understand the long-term characteristics of hydroclimatic processes, how does one find the prudent and reasonable course needed for water management? We consider this question in light of three aspects of existing and unresolved issues affecting hydroclimatic variability and statistical inference: Hurst-Kolmogorov phenomena; the complications long-term persistence introduces with respect to statistical understanding; and the dependence of process understanding on arbitrary sampling choices. These problems are not easily addressed. In such circumstances, humility may be more important than physics; a simple model with well-understood flaws may be preferable to a sophisticated model whose correspondence to reality is uncertain. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.
Ancient Glass: A Literature Search and its Role in Waste Management
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strachan, Denis M.; Pierce, Eric M.
2010-07-01
When developing a performance assessment model for the long-term disposal of immobilized low-activity waste (ILAW) glass, it is desirable to determine the durability of glass forms over very long periods of time. However, testing is limited to short time spans, so experiments are performed under conditions that accelerate the key geochemical processes that control weathering. Verification that models currently being used can reliably calculate the long term behavior ILAW glass is a key component of the overall PA strategy. Therefore, Pacific Northwest National Laboratory was contracted by Washington River Protection Solutions, LLC to evaluate alternative strategies that can be usedmore » for PA source term model validation. One viable alternative strategy is the use of independent experimental data from archaeological studies of ancient or natural glass contained in the literature. These results represent a potential independent experiment that date back to approximately 3600 years ago or 1600 before the current era (bce) in the case of ancient glass and 106 years or older in the case of natural glass. The results of this literature review suggest that additional experimental data may be needed before the result from archaeological studies can be used as a tool for model validation of glass weathering and more specifically disposal facility performance. This is largely because none of the existing data set contains all of the information required to conduct PA source term calculations. For example, in many cases the sediments surrounding the glass was not collected and analyzed; therefore having the data required to compare computer simulations of concentration flux is not possible. This type of information is important to understanding the element release profile from the glass to the surrounding environment and provides a metric that can be used to calibrate source term models. Although useful, the available literature sources do not contain the required information needed to simulate the long-term performance of nuclear waste glasses in a near-surface or deep geologic repositories. The information that will be required include 1) experimental measurements to quantify the model parameters, 2) detailed analyses of altered glass samples, and 3) detailed analyses of the sediment surrounding the ancient glass samples.« less
Impact of recipient body mass index on short-term and long-term survival of pancreatic grafts.
Bédat, Benoît; Niclauss, Nadja; Jannot, Anne-Sophie; Andres, Axel; Toso, Christian; Morel, Philippe; Berney, Thierry
2015-01-01
The impact of recipient body mass index on graft and patient survival after pancreas transplantation is not well known. We have analyzed data from all pancreas transplant recipients reported in the Scientific Registry of Transplant Recipients between 1987 and 2011. Recipients were categorized into BMI classes, as defined by the World Health Organization. Short-term (90 days) and long-term (90 days to 5 years) patient and graft survivals were analyzed according to recipient BMI class using Kaplan-Meier estimates. Hazard ratios were estimated using Cox proportional hazard models. A total of 21,075 adult recipients were included in the analysis. Mean follow-up was 5 ± 1.1 years. Subjects were overweight or obese in 39%. Increasing recipient BMI was an independent predictor of pancreatic graft loss and patient death in the short term (P<0.001), especially for obese class II patient survival (hazard ratio, 2.07; P=0.009). In the long term, obesity, but not overweight, was associated with higher risk of graft failure (P=0.01). Underweight was associated with a higher risk of long-term death (P<0.001). These results question the safety of pancreas transplantation in obese patients and suggest that they may be directed to alternate therapies, such as behavioral modifications or bariatric surgery, before pancreas transplantation is considered.
Joca, Lauren; Zuloaga, Damian G; Raber, Jacob; Siegel, Jessica A
2014-01-01
Methamphetamine (MA) has neurotoxic effects on the adult human brain that can lead to deficits in behavior and cognition. However, relatively little research has examined the behavioral or neurotoxic effects of MA in adolescents. The rising rates of adolescent MA use make it imperative that we understand the long-term effects of MA exposure on the adolescent brain and how these effects may differ from those seen in adults. In this study, the long-term effects of MA exposure during early adolescence on behavior and the vasopressin system in the paraventricular nucleus of the hypothalamus in late adolescent and adult male and female C57BL/6J mice were examined. MA exposure increased depression-like behavior in the Porsolt forced swim test in both late adolescent and adult male and female mice. Late adolescent male mice exposed to MA also showed a decrease in the number of vasopressin-immunoreactive neurons in the paraventricular nucleus compared to sex-matched saline-treated controls. Thus, similar to humans exposed to MA during adolescence, mice exposed to MA during adolescence show increased depression-like behavior later in life. These changes in behavior may be related to MA-induced alterations in vasopressin and the hypothalamic-pituitary-adrenal axis, especially in males. 2014 S. Karger AG, Basel
Grappi, Silvia; Marchese, Giovanna; Secci, Maria Elena; De Montis, Maria Graziella; Gambarana, Carla; Scheggi, Simona
2011-10-01
Repeated unavoidable stress induces in rats decreased reactivity to avoidable stressors and an anhedonia-like condition that are reverted by long-term antidepressant treatments and regarded as models of core symptoms of depression. Morphine-sensitized rats present resilience to stress-induced behavioral deficits and, if hyporeactivity to stress models a depressive symptom, stress resistance can be regarded as a manic symptom. This hypothesis is supported by the observation that long-term lithium administration reinstates sensitivity to stress in sensitized rats. The first aim of the study was to examine the effects of carbamazepine, a standard antimanic treatment, on the stress resilience of sensitized rats, to further characterize morphine sensitization as a model of manic symptom. Carbamazepine administration abolished stress resilience but did not interfere with the expression of sensitization. The second aim of the study was to assess whether repeated carbamazepine treatment affected the dopaminergic and behavioral responses to a natural reward, a palatable food (vanilla sugar, VS), in non food-deprived sensitized and control rats and compare these possible effects with those of repeated lithium administration. Control and sensitized rats showed increased extraneuronal dopamine levels in the nucleus accumbens shell after VS consumption and competence to acquire an instrumental VS-sustained appetitive behavior (VAB). Repeated carbamazepine treatment abolished the dopaminergic response to VS consumption and disrupted the competence to acquire VAB in control rats. Lithium-treated rats showed a dopaminergic response to VS and easily acquired the appetitive behavior. In sensitized rats, neither carbamazepine nor lithium administration interfered with the dopaminergic response to VS and the acquisition of VAB. In summary, the effect of carbamazepine on the stress resilience of sensitized rats further supported the hypothesis that morphine sensitization might model some symptoms of mania. Moreover, in control rats carbamazepine treatment elicited an anhedonia-like condition that clearly distinguished the effects of this drug from those of lithium. Copyright © 2011 Elsevier Inc. All rights reserved.
Frontal Lobe Contusion in Mice Chronically Impairs Prefrontal-Dependent Behavior
Rosi, Susanna
2016-01-01
Traumatic brain injury (TBI) is a major cause of chronic disability in the world. Moderate to severe TBI often results in damage to the frontal lobe region and leads to cognitive, emotional, and social behavioral sequelae that negatively affect quality of life. More specifically, TBI patients often develop persistent deficits in social behavior, anxiety, and executive functions such as attention, mental flexibility, and task switching. These deficits are intrinsically associated with prefrontal cortex (PFC) functionality. Currently, there is a lack of analogous, behaviorally characterized TBI models for investigating frontal lobe injuries despite the prevalence of focal contusions to the frontal lobe in TBI patients. We used the controlled cortical impact (CCI) model in mice to generate a frontal lobe contusion and studied behavioral changes associated with PFC function. We found that unilateral frontal lobe contusion in mice produced long-term impairments to social recognition and reversal learning while having only a minor effect on anxiety and completely sparing rule shifting and hippocampal-dependent behavior. PMID:26964036
ERIC Educational Resources Information Center
Moore, Jay
2010-01-01
Psychologists and philosophers have long been interested in two questions: (a) What do mental terms mean? and (b) what role do mental terms play in explanations of behavior? In the current sketch I review how mediational neobehaviorism, cognitive psychology, and the radical behaviorism of B. F. Skinner address these questions. In so doing, I seek…
Bribes for Behaving: Why Behaviorism Doesn't Help Children Become Good People.
ERIC Educational Resources Information Center
Kohn, Alfie
1994-01-01
Argues against using punishment and rewards to motivate children, maintaining that, although penalties and prizes may change behavior in the short term, they do not help children become responsible decision makers in the long term. (MDM)
NASA Astrophysics Data System (ADS)
Georgiou, K.; Abramoff, R. Z.; Harte, J.; Riley, W. J.; Torn, M. S.
2016-12-01
As global temperatures and atmospheric CO2 concentrations continue to increase, soil microbial activity and decomposition of soil organic matter (SOM) are expected to follow suit, potentially limiting soil carbon storage. Traditional global- and ecosystem-scale models simulate SOM decomposition using linear kinetics, which are inherently unable to reproduce carbon-concentration feedbacks, such as priming of native SOM at elevated CO2 concentrations. Recent studies using nonlinear microbial models of SOM decomposition seek to capture these interactions, and several groups are currently integrating these microbial models into Earth System Models (ESMs). However, despite their widespread ability to exhibit nonlinear responses, these models vary tremendously in complexity and, consequently, dynamics. In this study, we explore, both analytically and numerically, the emergent oscillatory behavior and insensitivity of SOM stocks to carbon inputs that have been deemed `unrealistic' in recent microbial models. We discuss the sources of instability in four models of varying complexity, by sequentially reducing complexity of a detailed model that includes microbial physiology, a mineral sorption isotherm, and enzyme dynamics. We also present an alternative representation of microbial turnover that limits population sizes and, thus, reduces oscillations. We compare these models to several long-term carbon input manipulations, including the Detritus Input and Removal Treatment (DIRT) experiments, to show that there are clear metrics that can be used to distinguish and validate the inherent dynamics of each model structure. We find that traditional linear and nonlinear models cannot readily capture the range of long-term responses observed across the DIRT experiments as a direct consequence of their model structures, and that modifying microbial turnover results in more realistic predictions. Finally, we discuss our findings in the context of improving microbial model behavior for inclusion in ESMs.
Andersson, E; Steneby, S; Karlsson, K; Ljótsson, B; Hedman, E; Enander, J; Kaldo, V; Andersson, G; Lindefors, N; Rück, C
2014-10-01
As relapse after completed cognitive behavior therapy (CBT) for obsessive-compulsive disorder (OCD) is common, many treatment protocols include booster programs to improve the long-term effects. However, the effects of booster programs are not well studied. In this study, we investigated the long-term efficacy of Internet-based CBT (ICBT) with therapist support for OCD with or without an Internet-based booster program. A total of 101 participants were included in the long-term follow-up analysis of ICBT. Of these, 93 were randomized to a booster program or no booster program. Outcome assessments were collected at 4, 7, 12 and 24 months after receiving ICBT. The entire sample had sustained long-term effects from pre-treatment to all follow-up assessments, with large within-group effect sizes (Cohen's d = 1.58-2.09). The booster group had a significant mean reduction in OCD symptoms compared to the control condition from booster baseline (4 months) to 7 months, but not at 12 or 24 months. Participants in the booster group improved significantly in terms of general functioning at 7, 12 and 24 months, and had fewer relapses. Kaplan-Meier analysis also indicated a significantly slower relapse rate in the booster group. The results suggest that ICBT has sustained long-term effects and that adding an Internet-based booster program can further improve long-term outcome and prevent relapse for some OCD patients.
Tuning Into Brown Dwarfs: Long-Term Radio Monitoring of Two Very Low Mass Dwarfs
NASA Astrophysics Data System (ADS)
Van Linge, Russell; Burgasser, Adam J.; Melis, Carl; Williams, Peter K. G.
2017-01-01
The very lowest-mass (VLM) stars and brown dwarfs, with effective temperatures T < 3000 K, exhibit mixed magnetic activity trends, with H-alpha and X-ray emission that declines rapidly beyond type M7/M8, but persistent radio emission in roughly 10-20% of sources. The dozen or so VLM radio emitters known show a broad range of emission characteristics and time-dependent behavior, including steady persistent emission, periodic oscillations, periodic polarized bursts, and aperiodic flares. Understanding the evolution of these variability patterns, and in particular whether they undergo solar-like cycles, requires long-term monitoring. We report the results of a long-term JVLA monitoring program of two magnetically-active VLM dwarf binaries, the young M7 2MASS 1314+1320AB and older L5 2MASS 1315-2649AB. On the bi-weekly cadence, 2MASS 1314 continues to show variability by revealing regular flaring while 2MASS 1315 continues to be a quiescent emitter. On the daily time scale, both sources show a mean flux density that can vary significantly just over a few days. These results suggest long-term radio behavior in radio-emitting VLM dwarfs is just as diverse and complex as short-term behavior.
Glazer, Lilah; Wells, Corinne N; Drastal, Meghan; Odamah, Kathryn-Ann; Galat, Richard E; Behl, Mamta; Levin, Edward D
2018-05-01
Polybrominated diphenyl ethers (PBDEs) were widely used as flame retardants until the early 2000s, mainly in home furnishings and electronics. The persistence of PBDEs in the environment leads to continued ubiquitous exposure to low levels, with infants and children experiencing higher exposures than adults. Accumulating evidence suggest that low-level exposures during early life stages can affect brain development and lead to long-term behavioral impairments. We investigated the effects of zebrafish exposure to low doses of the two prominent PBDEs; 2,2',4,4',5,-Pentabromodiphenyl ether (BDE-99) and 2,2',4,4',-Tetrabromodiphenyl ether (BDE-47), during embryo-development on short- and long-term behavioral endpoints. We included the organophosphate pesticide chlorpyrifos (CPF) due to its well documented neurotoxicity across species from zebrafish to humans. Zebrafish embryos were exposed to the following individual treatments; 0.1% DMSO (vehicle control); 0.3μM CPF; 0.01, 0.03, 0.1, 0.3μM BDE-47; 0.003, 0.03, 0.3, 1, 3, 10, 20μM BDE-99 from 5 until 120h post fertilization (hpf). Low exposure levels were determined as those not causing immediate overt toxicity, and behavior assays were conducted in the low-level range. At 144 hpf the larvae were tested for locomotor activity. At approximately 6 months of age adult zebrafish were tested in a behavioral battery including assays for anxiety-related behavior, sensorimotor response and habituation, social interaction, and predator avoidance. In the short-term, larval locomotor activity was reduced in larvae treated with 0.3μM CPF and 0.1μM BDE-47. BDE-99 treatment caused non-monotonic dose effects, with 0.3μM causing hyperactivity and 1μM or higher causing hypoactivity. In the long-term, adult anxiety-related behavior was reduced in all treatments as measured in both the novel tank dive test and tap test. We show that exposure of zebrafish embryos to low concentrations of the brominated flame retardants BDE-47 and BDE-99, and the organophosphate pesticide CPF, caused both short- and long-term behavioral impairments. Interestingly, we also found that at very low exposure concentrations, where there were no visible effects on larval activity, adult behavior was still strongly affected. Copyright © 2017 Elsevier B.V. All rights reserved.
Campbell, Mari; Clarke, Alex; Symes, Andrew; Workman, Sarita; Stauss, Hans; Webster, A David
2018-02-01
Patients with primary antibody deficiency report poorer quality of life and higher rates of anxiety and depression than the general population. Cognitive-behavioral therapy has been shown to be a valuable treatment for patients with other long-term physical health conditions, improving well-being and enabling them to manage their symptoms more effectively. The aim of this project was to establish the feasibility and effectiveness of providing cognitive-behavioral based therapy to patients with primary antibody deficiency. Forty-four patients completed a course of psychological therapy. Participants completed a series of self-report measures examining psychological and physical health, and service usage, prior to starting treatment and following their final session. They also provided feedback on their experience of treatment. Patients showed improvements in anxiety, depression, insomnia and fatigue. There was a high level of acceptability of the service and the potential for long-term cost savings to the NHS. Psychological therapy based on the cognitive-behavioral model of treatment appears to be a valuable treatment for patients with primary antibody deficiency and comorbid mental health difficulties.
The effectiveness of experiential environmental education: O'Neill Sea Odyssey program case study
NASA Astrophysics Data System (ADS)
Hanneman, Lauren E.
Environmental education programs aim to develop participant awareness, sensitivity, and understanding of their affective relationship to the natural environment through conceptual knowledge and personal experiences. Previous findings have suggested that participation in environmental education programs leads to short-term positive increases in environmental knowledge, pro-environmental attitudes, and intentions to act in environmentally responsible behaviors; however, few studies have included long-term, follow-up assessment. This research provided an analysis of the effectiveness of the O'Neill Sea Odyssey (OSO) education program in fostering a long-term awareness of personal responsibility about ocean pollution among student participants. A survey administered to 261 students from the greater San Francisco Bay Area in California was used to explore 7th through 10 th grade students' conceptions about the connection between ocean pollution and stewardship behaviors. The study revealed that 75% of 86 former OSO participants retained a high level of awareness of the connection between non-point source pollution and personal behaviors two to five years after the program, regardless of differences in sex, language, grade level, and community setting. These results indicate that OSO participants retained a long-term conceptual awareness about environmental stewardship behaviors taught during the OSO program.
2012-01-01
Background In childhood, attention deficit/hyperactivity disorder (ADHD) is characterized by age-inappropriate levels of inattentiveness/disorganization, hyperactivity/impulsiveness, or a combination thereof. Although the criteria for ADHD are well defined, the long-term consequences in adults and children need to be more comprehensively understood and quantified. We conducted a systematic review evaluating the long-term outcomes (defined as 2 years or more) of ADHD with the goal of identifying long-term outcomes and the impact that any treatment (pharmacological, non-pharmacological, or multimodal) has on ADHD long-term outcomes. Methods Studies were identified using predefined search criteria and 12 databases. Studies included were peer-reviewed, primary studies of ADHD long-term outcomes published between January 1980 to December 2010. Inclusion was agreed on by two independent researchers on review of abstracts or full text. Published statistical comparison of outcome results were summarized as poorer than, similar to, or improved versus comparators, and quantified as percentage comparisons of these categories. Results Outcomes from 351 studies were grouped into 9 major categories: academic, antisocial behavior, driving, non-medicinal drug use/addictive behavior, obesity, occupation, services use, self-esteem, and social function outcomes. The following broad trends emerged: (1) without treatment, people with ADHD had poorer long-term outcomes in all categories compared with people without ADHD, and (2) treatment for ADHD improved long-term outcomes compared with untreated ADHD, although not usually to normal levels. Only English-language papers were searched and databases may have omitted relevant studies. Conclusions This systematic review provides a synthesis of studies of ADHD long-term outcomes. Current treatments may reduce the negative impact that untreated ADHD has on life functioning, but does not usually 'normalize' the recipients. PMID:22947230
Long-term oscillations of sunspots and a special class of artifacts in SOHO/MDI and SDO/HMI data
NASA Astrophysics Data System (ADS)
Efremov, V. I.; Solov'ev, A. A.; Parfinenko, L. D.; Riehokainen, A.; Kirichek, E.; Smirnova, V. V.; Varun, Y. N.; Bakunina, I.; Zhivanovich, I.
2018-03-01
A specific type of artifacts (named as " p2p"), that originate due to displacement of the image of a moving object along the digital (pixel) matrix of receiver are analyzed in detail. The criteria of appearance and the influence of these artifacts on the study of long-term oscillations of sunspots are deduced. The obtained criteria suggest us methods for reduction or even elimination of these artifacts. It is shown that the use of integral parameters can be very effective against the " p2p" artifact distortions. The simultaneous observations of sunspot magnetic field and ultraviolet intensity of the umbra have given the same periods for the long-term oscillations. In this way the real physical nature of the oscillatory process, which is independent of the artifacts have been confirmed again. A number of examples considered here confirm the dependence between the periods of main mode of the sunspot magnetic field long-term oscillations and its strength. The dependence was derived earlier from both the observations and the theoretical model of the shallow sunspot. The anti-phase behavior of time variations of sunspot umbra area and magnetic field of the sunspot demonstrates that the umbra of sunspot moves in long-term oscillations as a whole: all its points oscillate with the same phase.
Algorithm for Automatic Behavior Quantification of Laboratory Mice Using High-Frame-Rate Videos
NASA Astrophysics Data System (ADS)
Nie, Yuman; Takaki, Takeshi; Ishii, Idaku; Matsuda, Hiroshi
In this paper, we propose an algorithm for automatic behavior quantification in laboratory mice to quantify several model behaviors. The algorithm can detect repetitive motions of the fore- or hind-limbs at several or dozens of hertz, which are too rapid for the naked eye, from high-frame-rate video images. Multiple repetitive motions can always be identified from periodic frame-differential image features in four segmented regions — the head, left side, right side, and tail. Even when a mouse changes its posture and orientation relative to the camera, these features can still be extracted from the shift- and orientation-invariant shape of the mouse silhouette by using the polar coordinate system and adjusting the angle coordinate according to the head and tail positions. The effectiveness of the algorithm is evaluated by analyzing long-term 240-fps videos of four laboratory mice for six typical model behaviors: moving, rearing, immobility, head grooming, left-side scratching, and right-side scratching. The time durations for the model behaviors determined by the algorithm have detection/correction ratios greater than 80% for all the model behaviors. This shows good quantification results for actual animal testing.
Processes of Personality Development in Adulthood: The TESSERA Framework.
Wrzus, Cornelia; Roberts, Brent W
2017-08-01
The current article presents a theoretical framework of the short- and long-term processes underlying personality development throughout adulthood. The newly developed TESSERA framework posits that long-term personality development occurs due to repeated short-term, situational processes. These short-term processes can be generalized as recursive sequence of Triggering situations, Expectancy, States/State expressions, and Reactions (TESSERA). Reflective and associative processes on TESSERA sequences can lead to personality development (i.e., continuity and lasting changes in explicit and implicit personality characteristics and behavioral patterns). We illustrate how the TESSERA framework facilitates a more comprehensive understanding of normative and differential personality development at various ages during the life span. The TESSERA framework extends previous theories by explicitly linking short- and long-term processes of personality development, by addressing different manifestations of personality, and by being applicable to different personality characteristics, for example, behavioral traits, motivational orientations, or life narratives.
Voegtlin, T; Verschure, P F
1999-01-01
This paper argues for the development of synthetic approaches towards the study of brain and behavior as a complement to the more traditional empirical mode of research. As an example we present our own work on learning and problem solving which relates to the behavioral paradigms of classical and operant conditioning. We define the concept of learning in the context of behavior and lay out the basic methodological requirements a model needs to satisfy, which includes evaluations using robots. In addition, we define a number of design principles neuronal models should obey to be considered relevant. We present in detail the construction of a neural model of short- and long-term memory which can be applied to an artificial behaving system. The presented model (DAC4) provides a novel self-consistent implementation of these processes, which satisfies our principles. This model will be interpreted towards the present understanding of the neuronal substrate of memory.
Hamiltonian Analysis of Subcritical Stochastic Epidemic Dynamics
2017-01-01
We extend a technique of approximation of the long-term behavior of a supercritical stochastic epidemic model, using the WKB approximation and a Hamiltonian phase space, to the subcritical case. The limiting behavior of the model and approximation are qualitatively different in the subcritical case, requiring a novel analysis of the limiting behavior of the Hamiltonian system away from its deterministic subsystem. This yields a novel, general technique of approximation of the quasistationary distribution of stochastic epidemic and birth-death models and may lead to techniques for analysis of these models beyond the quasistationary distribution. For a classic SIS model, the approximation found for the quasistationary distribution is very similar to published approximations but not identical. For a birth-death process without depletion of susceptibles, the approximation is exact. Dynamics on the phase plane similar to those predicted by the Hamiltonian analysis are demonstrated in cross-sectional data from trachoma treatment trials in Ethiopia, in which declining prevalences are consistent with subcritical epidemic dynamics. PMID:28932256
Association Between Traumatic Brain Injury-Related Brain Lesions and Long-term Caregiver Burden.
Guevara, Andrea Brioschi; Demonet, Jean-Francois; Polejaeva, Elena; Knutson, Kristine M; Wassermann, Eric M; Grafman, Jordan; Krueger, Frank
2016-01-01
To investigate the association between traumatic brain injury (TBI)-related brain lesions and long-term caregiver burden in relation to dysexecutive syndrome. National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland. A total of 256 participants: 105 combat veterans with TBI, 23 healthy control combat veterans (HCv), and 128 caregivers. Caregiver burden assessed by the Zarit Burden Interview at 40 years postinjury. Participants with penetrating TBI were compared with HCv on perceived caregiver burden and neuropsychological assessment measures. Data of computed tomographic scans (overlay lesion maps of participants with a penetrating TBI whose caregivers have a significantly high burden) and behavioral statistical analyses were combined to identify brain lesions associated with caregiver burden. Burden was greater in caregivers of veterans with TBI than in caregivers of HCv. Caregivers of participants with lesions affecting cognitive and behavioral indicators of dysexecutive syndrome (ie, left dorsolateral prefrontal cortex and dorsal anterior cingulate cortex) showed greater long-term burden than caregivers of participants with lesions elsewhere in the brain. The TBI-related brain lesions have a lasting effect on long-term caregiver burden due to cognitive and behavioral factors associated with dysexecutive syndrome.
Long-Term Viscoelastic Response of E-glass/Bismaleimide Composite in Seawater Environment
NASA Astrophysics Data System (ADS)
Yian, Zhao; Zhiying, Wang; Keey, Seah Leong; Boay, Chai Gin
2015-12-01
The effect of seawater absorption on the long-term viscoelastic response of E-glass/BMI composite is presented in this paper. The diffusion of seawater into the composite shows a two-stage behavior, dominated by Fickian diffusion initially and followed by polymeric relaxation. The Glass transition temperature (Tg) of the composite with seawater absorption is considerably lowered due to the plasticization effect. However the effect of water absorption at 50 °C is found to be reversible after drying process. The time-temperature superposition (TTS) was performed based on the results of Dynamic Mechanical Analysis to construct the master curve of storage modulus. The shift factors exhibit Arrhenius behavior when temperature is well below Tg and Vogel-Fulcher-Tammann (VFT) like behavior when temperature gets close to glass transition region. As a result, a semi-empirical formulation is proposed to account for the seawater absorption effect in predicting long-term viscoelastic response of BMI composites based on temperature dependent storage modulus and TTS. The predicted master curves show that the degradation of storage modulus accelerates with both seawater exposure and increasing temperature. The proposed formulation can be applied to predict the long-term durability of any thermorheologically simple composite materials in seawater environment.
Ikegami, Aiko; Olsen, Christopher M.; D’Souza, Manoranjan S.; Duvauchelle, Christine L.
2008-01-01
Experiments were performed to examine the effects of cocaine self-administration and conditioning experience on operant behavior, locomotor activity, and nucleus accumbens (NAcc) and prefrontal cortex (PFC) dopamine (DA) responses. Sensory cues were paired with alternating cocaine and nonreinforcement during 12 (limited training) or 40 (long-term training) daily operant sessions. After limited training, NAcc DA responses to cocaine were significantly enhanced in the presence of cocaine-associated cues compared with nonreward cues and significantly depressed after cocaine-paired cues accompanied a nonreinforced lever response. PFC DA levels were generally nonresponsive to cues after the same training duration. However, after long-term training, cocaine-associated cues increased the magnitude of cocaine-stimulated PFC DA levels significantly over levels observed with nonreinforcement cues. Conversely, conditioned cues no longer influenced NAcc DA levels after long-term training. In addition, cocaine-stimulated locomotor activity was enhanced by cocaine-paired cues after long-term, but not after limited, training. Findings demonstrate that cue-induced cocaine expectation exerts a significant impact on dopaminergic and behavioral systems, progressing from mesolimbic to mesocortical regions and from latent to patent behaviors as cocaine and associative experiences escalate. PMID:17469929
Long-term Behavioral Tracking of Freely Swimming Weakly Electric Fish
Jun, James J.; Longtin, André; Maler, Leonard
2014-01-01
Long-term behavioral tracking can capture and quantify natural animal behaviors, including those occurring infrequently. Behaviors such as exploration and social interactions can be best studied by observing unrestrained, freely behaving animals. Weakly electric fish (WEF) display readily observable exploratory and social behaviors by emitting electric organ discharge (EOD). Here, we describe three effective techniques to synchronously measure the EOD, body position, and posture of a free-swimming WEF for an extended period of time. First, we describe the construction of an experimental tank inside of an isolation chamber designed to block external sources of sensory stimuli such as light, sound, and vibration. The aquarium was partitioned to accommodate four test specimens, and automated gates remotely control the animals' access to the central arena. Second, we describe a precise and reliable real-time EOD timing measurement method from freely swimming WEF. Signal distortions caused by the animal's body movements are corrected by spatial averaging and temporal processing stages. Third, we describe an underwater near-infrared imaging setup to observe unperturbed nocturnal animal behaviors. Infrared light pulses were used to synchronize the timing between the video and the physiological signal over a long recording duration. Our automated tracking software measures the animal's body position and posture reliably in an aquatic scene. In combination, these techniques enable long term observation of spontaneous behavior of freely swimming weakly electric fish in a reliable and precise manner. We believe our method can be similarly applied to the study of other aquatic animals by relating their physiological signals with exploratory or social behaviors. PMID:24637642
The evolution of Drosophila melanogaster as a model for alcohol research.
Devineni, Anita V; Heberlein, Ulrike
2013-07-08
Animal models have been widely used to gain insight into the mechanisms underlying the acute and long-term effects of alcohol exposure. The fruit fly Drosophila melanogaster encounters ethanol in its natural habitat and possesses many adaptations that allow it to survive and thrive in ethanol-rich environments. Several assays to study ethanol-related behaviors in flies, ranging from acute intoxication to self-administration and reward, have been developed in the past 20 years. These assays have provided the basis for studying the physiological and behavioral effects of ethanol and for identifying genes mediating these effects. In this review we describe the ecological relationship between flies and ethanol, the effects of ethanol on fly development and behavior, the use of flies as a model for alcohol addiction, and the interaction between ethanol and social behavior. We discuss these advances in the context of their utility to help decipher the mechanisms underlying the diverse effects of ethanol, including those that mediate ethanol dependence and addiction in humans.
Hippocampal mechanisms for the context-dependent retrieval of episodes
Hasselmo, Michael E.; Eichenbaum, Howard B.
2008-01-01
Behaviors ranging from delivering newspapers to waiting tables depend on remembering previous episodes to avoid incorrect repetition. Physiologically, this requires mechanisms for long-term storage and selective retrieval of episodes based on time of occurrence, despite variable intervals and similarity of events in a familiar environment. Here, this process has been modeled based on physiological properties of the hippocampal formation, including mechanisms for sustained activity in entorhinal cortex and theta rhythm oscillations in hippocampal subregions. The model simulates the context-sensitive firing properties of hippocampal neurons including trial specific firing during spatial alternation and trial by trial changes in theta phase precession on a linear track. This activity is used to guide behavior, and lesions of the hippocampal network impair memory-guided behavior. The model links data at the cellular level to behavior at the systems level, describing a physiologically plausible mechanism for the brain to recall a given episode which occurred at a specific place and time. PMID:16263240
Ashby, Donovan M; Habib, Diala; Dringenberg, Hans C; Reynolds, James N; Beninger, Richard J
2010-09-01
Subchronic NMDA receptor antagonist treatment and post-weaning social isolation are two animal models of schizophrenia symptoms. However, behavioral and physiological changes following a combination of these two procedures have not been investigated. Thus, we examined effects of a novel, "double hit" model combining these two treatments, comparing them to standard models involving only NMDA antagonist treatment or social isolation. Male, Sprague-Dawley rats were either group-housed or maintained in social isolation (starting at postnatal day [PD] 21 and continuing throughout the study). Each housing condition was further subdivided into two groups, receiving either subchronic treatment with either saline or MK-801 (0.5mg/kg, i.p., 2xday for seven days starting at PD 56). Post-weaning social isolation increased locomotor activity (assessed at PD 70) in response to a novel environment and an acute amphetamine injection, while subchronic MK-801 increased only amphetamine induced locomotor activity. Subsequent electrophysiological experiments (under urethane anesthesia) assessing changes in plasticity of hippocampal synapses showed that subchronic MK-801 treatment resulted in an increase in long-term potentiation in area CA1 in response to high frequency stimulation of the contralateral CA3 area, while housing condition had no effect. No other changes in hippocampal electrophysiology (input-output curves, paired-pulse facilitation) were observed. These data are the first to demonstrate an enhancement in hippocampal long-term plasticity in vivo following subchronic MK-801 administration, an effect that may be related to the well-characterized changes in glutamatergic and GABAergic systems seen after subchronic NMDA receptor blockade. That lack of additive or synergistic effects in the "double hit model" suggests that combining isolation and subchronic MK-801 treatment does not necessarily produce greater behavioral or physiological dysfunction than that seen with either treatment alone. Copyright 2010 Elsevier B.V. All rights reserved.
d'Avila, Joana Costa; Siqueira, Luciana Domett; Mazeraud, Aurélien; Azevedo, Estefania Pereira; Foguel, Debora; Castro-Faria-Neto, Hugo Caire; Sharshar, Tarek; Chrétien, Fabrice; Bozza, Fernando Augusto
2018-01-30
Microglia function is essential to maintain the brain homeostasis. Evidence shows that aged microglia are primed and show exaggerated response to acute inflammatory challenge. Systemic inflammation signals to the brain inducing changes that impact cognitive function. However, the mechanisms involved in age-related cognitive decline associated to episodic systemic inflammation are not completely understood. The aim of this study was to identify neuropathological features associated to age-related cognitive decline in a mouse model of episodic systemic inflammation. Young and aged Swiss mice were injected with low doses of LPS once a week for 6 weeks to induce episodic systemic inflammation. Sickness behavior, inflammatory markers, and neuroinflammation were assessed in different phases of systemic inflammation in young and aged mice. Behavior was evaluated long term after episodic systemic inflammation by open field, forced swimming, object recognition, and water maze tests. Episodic systemic inflammation induced systemic inflammation and sickness behavior mainly in aged mice. Systemic inflammation induced depressive-like behavior in both young and aged mice. Memory and learning were significantly affected in aged mice that presented lower exploratory activity and deficits in episodic and spatial memories, compared to aged controls and to young after episodic systemic inflammation. Systemic inflammation induced acute microglia activation in young mice that returned to base levels long term after episodic systemic inflammation. Aged mice presented dystrophic microglia in the hippocampus and entorhinal cortex at basal level and did not change morphology in the acute response to SI. Regardless of their dystrophic microglia, aged mice produced higher levels of pro-inflammatory (IL-1β and IL-6) as well as pro-resolution (IL-10 and IL-4) cytokines in the brain. Also, higher levels of Nox2 expression, oxidized proteins and lower antioxidant defenses were found in the aged brains compared to the young after episodic systemic inflammation. Our data show that aged mice have increased susceptibility to episodic systemic inflammation. Aged mice that showed cognitive impairments also presented higher oxidative stress and abnormal production of cytokines in their brains. These results indicate that a neuroinflammation and oxidative stress are pathophysiological mechanisms of age-related cognitive impairments.
Predictive aging results in radiation environments
NASA Astrophysics Data System (ADS)
Gillen, Kenneth T.; Clough, Roger L.
1993-06-01
We have previously derived a time-temperature-dose rate superposition methodology, which, when applicable, can be used to predict polymer degradation versus dose rate, temperature and exposure time. This methodology results in predictive capabilities at the low dose rates and long time periods appropriate, for instance, to ambient nuclear power plant environments. The methodology was successfully applied to several polymeric cable materials and then verified for two of the materials by comparisons of the model predictions with 12 year, low-dose-rate aging data on these materials from a nuclear environment. In this paper, we provide a more detailed discussion of the methodology and apply it to data obtained on a number of additional nuclear power plant cable insulation (a hypalon, a silicone rubber and two ethylene-tetrafluoroethylenes) and jacket (a hypalon) materials. We then show that the predicted, low-dose-rate results for our materials are in excellent agreement with long-term (7-9 year) low-dose-rate results recently obtained for the same material types actually aged under bnuclear power plant conditions. Based on a combination of the modelling and long-term results, we find indications of reasonably similar degradation responses among several different commercial formulations for each of the following "generic" materials: hypalon, ethylene-tetrafluoroethylene, silicone rubber and PVC. If such "generic" behavior can be further substantiated through modelling and long-term results on additional formulations, predictions of cable life for other commercial materials of the same generic types would be greatly facilitated.
Sex differences and sex hormones in anxiety-like behavior of aging rats.
Domonkos, Emese; Borbélyová, Veronika; Csongová, Melinda; Bosý, Martin; Kačmárová, Mária; Ostatníková, Daniela; Hodosy, Július; Celec, Peter
2017-07-01
Sex differences in the prevalence of affective disorders might be attributable to different sex hormone milieu. The effects of short-term sex hormone deficiency on behavior, especially on anxiety have been studied in numerous animal experiments, mainly on young adult rats and mice. However, sex differences in aged animals and the effects of long-term hypogonadism are understudied. The aim of our study was to analyze sex differences in anxiety-like behavior in aged rats and to prove whether they can be attributed to endogenous sex hormone production in males. A battery of tests was performed to assess anxiety-like behavior in aged female, male and gonadectomized male rats castrated before puberty. In addition, the aged gonadectomized male rats were treated with a single injection of estradiol or testosterone or supplemented with estradiol for two-weeks. Female rats displayed a less anxious behavior than male rats in most of the conducted behavioral tests except the light-dark box. Long-term androgen deficiency decreased the sex difference in anxiety either partially (open field, PhenoTyper cage) or completely (elevated plus maze). Neither single injection of sex hormones, nor two-week supplementation of estradiol in gonadectomized aged male rats significantly affected their anxiety-like behavior in the elevated plus maze. In conclusion, our results confirm sex differences in anxiety in aged rats likely mediated by endogenous testosterone production in males. Whether long-term supplementation with exogenous sex hormones could affect anxiety-like behavior in elderly individuals remains to be elucidated. Copyright © 2017 Elsevier Inc. All rights reserved.
What Can We Learn from a Simple Physics-Based Earthquake Simulator?
NASA Astrophysics Data System (ADS)
Artale Harris, Pietro; Marzocchi, Warner; Melini, Daniele
2018-03-01
Physics-based earthquake simulators are becoming a popular tool to investigate on the earthquake occurrence process. So far, the development of earthquake simulators is commonly led by the approach "the more physics, the better". However, this approach may hamper the comprehension of the outcomes of the simulator; in fact, within complex models, it may be difficult to understand which physical parameters are the most relevant to the features of the seismic catalog at which we are interested. For this reason, here, we take an opposite approach and analyze the behavior of a purposely simple earthquake simulator applied to a set of California faults. The idea is that a simple simulator may be more informative than a complex one for some specific scientific objectives, because it is more understandable. Our earthquake simulator has three main components: the first one is a realistic tectonic setting, i.e., a fault data set of California; the second is the application of quantitative laws for earthquake generation on each single fault, and the last is the fault interaction modeling through the Coulomb Failure Function. The analysis of this simple simulator shows that: (1) the short-term clustering can be reproduced by a set of faults with an almost periodic behavior, which interact according to a Coulomb failure function model; (2) a long-term behavior showing supercycles of the seismic activity exists only in a markedly deterministic framework, and quickly disappears introducing a small degree of stochasticity on the recurrence of earthquakes on a fault; (3) faults that are strongly coupled in terms of Coulomb failure function model are synchronized in time only in a marked deterministic framework, and as before, such a synchronization disappears introducing a small degree of stochasticity on the recurrence of earthquakes on a fault. Overall, the results show that even in a simple and perfectly known earthquake occurrence world, introducing a small degree of stochasticity may blur most of the deterministic time features, such as long-term trend and synchronization among nearby coupled faults.
The 4-D approach to visual control of autonomous systems
NASA Technical Reports Server (NTRS)
Dickmanns, Ernst D.
1994-01-01
Development of a 4-D approach to dynamic machine vision is described. Core elements of this method are spatio-temporal models oriented towards objects and laws of perspective projection in a foward mode. Integration of multi-sensory measurement data was achieved through spatio-temporal models as invariants for object recognition. Situation assessment and long term predictions were allowed through maintenance of a symbolic 4-D image of processes involving objects. Behavioral capabilities were easily realized by state feedback and feed-foward control.
The Ease of Language Understanding (ELU) model: theoretical, empirical, and clinical advances
Rönnberg, Jerker; Lunner, Thomas; Zekveld, Adriana; Sörqvist, Patrik; Danielsson, Henrik; Lyxell, Björn; Dahlström, Örjan; Signoret, Carine; Stenfelt, Stefan; Pichora-Fuller, M. Kathleen; Rudner, Mary
2013-01-01
Working memory is important for online language processing during conversation. We use it to maintain relevant information, to inhibit or ignore irrelevant information, and to attend to conversation selectively. Working memory helps us to keep track of and actively participate in conversation, including taking turns and following the gist. This paper examines the Ease of Language Understanding model (i.e., the ELU model, Rönnberg, 2003; Rönnberg et al., 2008) in light of new behavioral and neural findings concerning the role of working memory capacity (WMC) in uni-modal and bimodal language processing. The new ELU model is a meaning prediction system that depends on phonological and semantic interactions in rapid implicit and slower explicit processing mechanisms that both depend on WMC albeit in different ways. It is based on findings that address the relationship between WMC and (a) early attention processes in listening to speech, (b) signal processing in hearing aids and its effects on short-term memory, (c) inhibition of speech maskers and its effect on episodic long-term memory, (d) the effects of hearing impairment on episodic and semantic long-term memory, and finally, (e) listening effort. New predictions and clinical implications are outlined. Comparisons with other WMC and speech perception models are made. PMID:23874273
NASA Technical Reports Server (NTRS)
Stewart, Mark E.
2017-01-01
Evaporation and condensation at a liquidvapor interface is important for long-term, in-space cryogenic propellant storage. Yet the current understanding of interfacial physics does not predict behavior or evaporation condensation rates. The proposed paper will present a physical model, based on the 1-D Heat equation and Schrages equation which demonstrates thin thermal layers at the fluidvapor interface.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Indacochea, J. E.; Gattu, V. K.; Chen, X.
The results of electrochemical corrosion tests and modeling activities performed collaboratively by researchers at the University of Illinois at Chicago and Argonne National Laboratory as part of workpackage NU-13-IL-UIC-0203-02 are summarized herein. The overall objective of the project was to develop and demonstrate testing and modeling approaches that could be used to evaluate the use of composite alloy/ceramic materials as high-level durable waste forms. Several prototypical composite waste form materials were made from stainless steels representing fuel cladding, reagent metals representing metallic fuel waste streams, and reagent oxides representing oxide fuel waste streams to study the microstructures and corrosion behaviorsmore » of the oxide and alloy phases. Microelectrodes fabricated from small specimens of the composite materials were used in a series of electrochemical tests to assess the corrosion behaviors of the constituent phases and phase boundaries in an aggressive acid brine solution at various imposed surface potentials. The microstructures were characterized in detail before and after the electrochemical tests to relate the electrochemical responses to changes in both the electrode surface and the solution composition. The results of microscopic, electrochemical, and solution analyses were used to develop equivalent circuit and physical models representing the measured corrosion behaviors of the different materials pertinent to long-term corrosion behavior. This report provides details regarding (1) the production of the composite materials, (2) the protocol for the electrochemical measurements and interpretations of the responses of multi-phase alloy and oxide composites, (3) relating corrosion behaviors to microstructures of multi-phase alloys based on 316L stainless steel and HT9 (410 stainless steel was used as a substitute) with added Mo, Ni, and/or Mn, and (4) modeling the corrosion behaviors and rates of several alloy/oxide composite materials made with added lanthanide and uranium oxides. These analyses show the corrosion behaviors of the alloy/ceramic composite materials are very similar to the corrosion behaviors of multi-phase alloy waste forms, and that the presence of oxide inclusions does not impact the corrosion behaviors of the alloy phases. Mixing with metallic waste streams is beneficial to lanthanide and uranium oxides in that they react with Zr in the fuel waste to form highly durable zirconates. The measured corrosion behaviors suggest properly formulated composite materials would be suitable waste forms for combined metallic and oxide waste streams generated during electrometallurgical reprocessing of spent nuclear fuel. Electrochemical methods are suitable for evaluating the durability and modeling long-term behavior of composite waste forms: the degradation model developed for metallic waste forms can be applied to the alloy phases formed in the composite and an affinity-based mineral dissolution model can be applied to the ceramic phases.« less
Tchekalarova, Jana D; Ivanova, Natasha; Atanasova, Dimitrina; Pechlivanova, Daniela M; Lazarov, Nikolai; Kortenska, Lidia; Mitreva, Rumiana; Lozanov, Valentin; Stoynev, Alexander
2016-08-01
Over the last 10 years, accumulated experimental and clinical evidence has supported the idea that AT1 receptor subtype is involved in epilepsy. Recently, we have shown that the selective AT1 receptor antagonist losartan attenuates epileptogenesis and exerts neuroprotection in the CA1 area of the hippocampus in epileptic Wistar rats. This study aimed to verify the efficacy of long-term treatment with losartan (10 mg/kg) after kainate-induced status epilepticus (SE) on seizure activity, behavioral and biochemical changes, and neuronal damage in a model of co-morbid hypertension and epilepsy. Spontaneous seizures were video- and EEG-monitored in spontaneously hypertensive rats (SHRs) for a 16-week period after SE. The behavior was analyzed by open field, elevated plus maze, sugar preference test, and forced swim test. The levels of serotonin in the hippocampus and neuronal loss were estimated by HPLC and hematoxylin and eosin staining, respectively. The AT1 receptor antagonism delayed the onset of seizures and alleviated their frequency and duration during and after discontinuation of treatment. Losartan showed neuroprotection mostly in the CA3 area of the hippocampus and the septo-temporal hilus of the dentate gyrus in SHRs. However, the AT1 receptor antagonist did not exert a substantial influence on concomitant with epilepsy behavioral changes and decreased 5-HT levels in the hippocampus. Our results suggest that the antihypertensive therapy with an AT1 receptor blocker might be effective against seizure activity and neuronal damage in a co-morbid hypertension and epilepsy.
Is the authoritative parenting model effective in changing oral hygiene behavior in adolescents?
Brukienė, Vilma; Aleksejūnienė, Jolanta
2012-12-01
This study examined whether the authoritative parenting model (APM) is more effective than conventional approaches for changing adolescent oral hygiene behavior. A total of 247 adolescents were recruited using a cluster random-sampling method. Subject groups were randomly allocated into an intervention group (APM-based interventions), a Control Group 1 (conventional dental education and behavior modification) or a Control Group 2 (conventional behavior modification). The results were assessed after 3 and 12 months. Oral hygiene level was assessed as percent dental plaque and the ratio of plaque percent change (RPC). At the 3-month follow-up, there were significant differences among the groups; the APM group had the largest decrease in plaque levels (24.5%), Control Group 1 showed a decrease in plaque levels of 15.4% and Control Group 2 showed an increase in plaque levels of 2.8%. At the 12-month follow-up, an improvement was observed in all groups, but there were no statistically significant differences among the groups. In the short term, the intervention based on the APM was more effective in changing adolescent oral hygiene behavior compared with the conventional approaches. The reasons for long-term positive change after discontinued interventions in control groups need to be explored in future studies.
NASA Astrophysics Data System (ADS)
Li, L.; Brunet, J. P. L.; Karpyn, Z.; Huerta, N. J.
2016-12-01
During geological carbon sequestration (GCS) large quantities of CO2 are injected in underground formations. Cement fractures represent preferential leakage pathways in abandoned wells upon exposure to CO2-rich fluid. Contrasting self- healing and fracture opening behavior have been observed while a unifying framework is still missing. The modelling of this process is challenging as it involves complex chemical, mechanical and transport interactions. We developed a process-based reactive transport model that explicitly simulates flow and multi-component reactive transport in fractured cement by reproducing experimental observations of sharp flow rate reduction during exposure to carbonated water. Mechanical interactions have not been included. The simulation shows a similar reaction network as in diffusion-controlled systems without flow. That is, CO2-rich water induced portlandite dissolution, releasing calcium that further reacted with carbonate to form calcite. This created localized changes in porosity and permeability inducing large differences in the long term response of the system through a complex positive feedback loop (e.g., a decrease in local permeability induces a decrease in flow that in turn amplifies the precipitation of calcite through a reduced acidic brine flow). The calibrated model was used to generate 250 numerical experiments of CO2-flooding in cement fractures with varying initial hydraulic apertures (b) and residence times (τ) defined as the ratio of fracture volume over flow rate. A long τ leads to slow replenishment of carbonated water, calcite precipitation, and self-sealing. The opposite occurs when τ is small with short fractures and fast flow rates. Simulation results indicate that a critical residence time τc - the minimum τ required for self-sealing -divides the conditions that trigger the diverging opening and self-sealing behavior. The τc value depends on the initial aperture size (see figure). Among the 250 simulated fracture cases, significant changes in effective permeability - self-healing or opening - typically occurs within hours to a day, thus providing a supporting argument for the extrapolation of short-term laboratory observations (hours to months) to long-term predictions at relevant GCS time scales (years to hundreds of years).
Follow-up Medical Care After Cancer Treatment
... long-term effects, and to study health-related quality of life and behaviors in long-term survivors. Healthcare Delivery ... perceptions, knowledge, and practices of primary care and oncology specialist physicians about follow-up care of adult cancer survivors after treatment. ... for Childhood Cancer Survivors ...
Simulated response and effects to oil exposure in an estuarine fish species
Experimental toxicity data alone lack ecological relevance to assess more realistic situations, such as variable exposure to a contaminant and long-term impact. Evaluating the implications of sublethal effects or behavioral response to exposure requires long-term, population-leve...
Litrownik, Alan J.; Newton, Rae R.; Davis, Inger P.
2016-01-01
Objective This study aimed to identify children’s long-term placement trajectories following early child welfare involvement and the association of these trajectories with subsequent physical and behavioral well-being. Method Participants were 330 children who entered out-of-home care following a substantiated report of child abuse or neglect during infancy/early childhood and their caregivers. Participants were interviewed at child ages 4 and 12 years to assess children’s physical and behavioral well-being and every 2 years in between to determine child placements. Results Latent Class Analyses identified four stable placement trajectories (i.e., adopted [32%], kinship care [15%], stable reunified [27%], and stable foster care [9%]), and two unstable trajectories (i.e., disrupted reunified [12%] and unstable foster care [5%]). Logistic regressions revealed that children in the unstable trajectories had significantly poorer physical and behavioral well-being than children in stable trajectories. Conclusions and Relevance Maltreated children placed in out-of-home care are at risk for long-term placement instability and poorer physical and behavioral well-being. PMID:25834181
Radiolytic and Thermal Process Relevant to Dry Storage of Spent Nuclear Fuels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marschman, Steven C.; Haustein, Peter E.; Madey, Theodore E.
1999-06-01
This project involves basic research in chemistry and physics aimed at providing information pertinent to the safe long-term dry storage of spent nuclear fuel (SNF), thousands of tons of which remain in water storage across the DOE complex. The Hanford Site K-Basins alone hold 2300 tons of spent fuel, much of it severely corroded, and similar situations exist at Savannah River and Idaho National Engineering and Environmental Laboratory. DOE plans to remove this fuel and seal it in overpack canisters for ''dry'' interim storage for up to 75 years while awaiting permanent disposition. Chemically bound water will remain in thismore » fuel even after the proposed drying steps, leading to possible long-term corrosion of the containers and/or fuel rods themselves, generation of H2 and O2 gas via radiolysis (which could lead to deflagration or detonation), and reactions of pyrophoric uranium hydrides. No thoroughly tested model is now available to predict fuel behavior during preprocessing, processing, or storage. In a collaborative effort among Rutgers University, Pacific Northwest National Laboratory, and Brookhaven National Laboratory, we are studying the radiolytic reaction, drying processes, and corrosion behavior of actual SNF materials and of pure and mixed-phase samples. We propose to determine what is omitted from current models: radiolysis of water adsorbed on or in hydrates or hydroxides, thermodynamics of interfacial phases, and kinetics of drying. A model will be developed and tested against actual fuel rod behavior to ensure validity and applicability to the problems associated with developing dry storage strategies for DOE-owned SNF.« less
Model and prediction of stress relaxation of polyurethane fiber
NASA Astrophysics Data System (ADS)
You, Gexin; Wang, Chunyan; Mei, Shuqin; Yang, Bo; Zhou, Xiuwen
2018-03-01
In this study, the effect of small strain (less than 10%) on hydrogen bond (H-bond) and crystallinity of dry-spun polyurethane fiber was investigated with fourier transform infrared spectroscopy and x-ray diffractometer, respectively. The results showed that the H-bond of hard segments hardly broke and its degree of crystallinity scarcely varied below strain of 10%. The fiber stress relaxation behavior at 25 °C under small strain was researched using dynamic mechanical analyzer. The stress relaxation modulus constitutive equation was obtained by transforming the non-linear relationship between stress and time into the linear relationship between stress and strain. The stress relaxation modulus master curve at 25 °C was established in terms of short-term stress relaxation tests at elevated temperatures (35 °C, 45 °C, 65 °C and 75 °C) according to time-temperature superposition principle (TTS) to predict long-term behavior within 353 year.
SPR Hydrostatic Column Model Verification and Validation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bettin, Giorgia; Lord, David; Rudeen, David Keith
2015-10-01
A Hydrostatic Column Model (HCM) was developed to help differentiate between normal "tight" well behavior and small-leak behavior under nitrogen for testing the pressure integrity of crude oil storage wells at the U.S. Strategic Petroleum Reserve. This effort was motivated by steady, yet distinct, pressure behavior of a series of Big Hill caverns that have been placed under nitrogen for extended period of time. This report describes the HCM model, its functional requirements, the model structure and the verification and validation process. Different modes of operation are also described, which illustrate how the software can be used to model extendedmore » nitrogen monitoring and Mechanical Integrity Tests by predicting wellhead pressures along with nitrogen interface movements. Model verification has shown that the program runs correctly and it is implemented as intended. The cavern BH101 long term nitrogen test was used to validate the model which showed very good agreement with measured data. This supports the claim that the model is, in fact, capturing the relevant physical phenomena and can be used to make accurate predictions of both wellhead pressure and interface movements.« less
Böckerman, Petri; Hyytinen, Ari; Kaprio, Jaakko; Maczulskij, Terhi
2018-06-01
This paper examines the links between risky health behaviors and labor market success. We provide new evidence on the joint relationships between the most prominent forms of risky health behavior - alcohol consumption, smoking and physical inactivity - and long-term labor market outcomes. We use twin data for Finnish men and women linked to register-based individual information on earnings and labor market attachment. The twin data allow us to account for shared family and environmental factors and to measure risky health behaviors in 1975 and 1981. The long-term labor market outcomes were measured in adulthood as an average over the period 1990-2009. The sample sizes are 2156 and 2498 twins, for men and women, respectively. We find that being both a smoker and a heavy drinker in early adulthood is negatively related to long-term earnings and employment later in life, especially for men. We conclude that how and why risky health behaviors cluster and how that affects individual level outcomes call for more attention. Copyright © 2018 Elsevier Ltd. All rights reserved.
Individual decision making in the non-purchase of long-term care insurance.
Curry, Leslie A; Robison, Julie; Shugrue, Noreen; Keenan, Patricia; Kapp, Marshall B
2009-08-01
Although prior research suggests that economic, behavioral, and psychosocial factors influence decisions not to purchase long-term care insurance, few studies have examined the interplay among these factors in depth and from the consumer's point of view. This study was intended to further illuminate these considerations, generate hypotheses about non-purchasing decisions, and inform the design of policies that are responsive to concerns and preferences of potential purchasers. Qualitative study using 32 in-depth interviews and 6 focus groups, following a grounded theory approach. Five themes characterize decisions not to purchase long-term care insurance: (a) the determination that a policy is "too costly" reflects highly individualized and complex trade-offs not solely economic in nature, (b) non-purchasers are skeptical about the viability and integrity of private insurance companies and seek an unbiased source of information, (c) family dynamics play an important role in insurance decisions, (d) contemplating personal risk for long-term care triggers psychological responses that have implications for decision making, and (e) non-purchasers feel inadequately informed and overwhelmed by the process of deciding whether to purchase long-term care insurance. States are seeking to offset escalating Medicaid long-term care expenditures through a variety of policy mechanisms, including stimulating individual purchase of long-term care insurance. Findings suggest that economic incentives such as lowering premiums will be necessary but not sufficient to attract appropriate candidates. Attention to behavioral and psychosocial factors is essential to designing incentives that are responsive to concerns and preferences of potential purchasers.
Evaluation of a non-Arrhenius model for therapeutic monoclonal antibody aggregation.
Kayser, Veysel; Chennamsetty, Naresh; Voynov, Vladimir; Helk, Bernhard; Forrer, Kurt; Trout, Bernhardt L
2011-07-01
Understanding antibody aggregation is of great significance for the pharmaceutical industry. We studied the aggregation of five different therapeutic monoclonal antibodies (mAbs) with size-exclusion chromatography-high-performance liquid chromatography (SEC-HPLC), fluorescence spectroscopy, electron microscopy, and light scattering methods at various temperatures with the aim of gaining insight into the aggregation process and developing models of it. In particular, we find that the kinetics can be described by a second-order model and are non-Arrhenius. Thus, we develop a non-Arrhenius model to connect accelerated aggregation experiments at high temperature to long-term storage experiments at low temperature. We evaluate our model by predicting mAb aggregation and comparing it with long-term behavior. Our results suggest that the number of monomers and mAb conformations within aggregates vary with the size and age of the aggregates, and that only certain sizes of aggregates are populated in the solution. We also propose a kinetic model based on conformational changes of proteins and monomer peak loss kinetics from SEC-HPLC. This model could be employed for a detail analysis of mAb aggregation kinetics. Copyright © 2011 Wiley-Liss, Inc. and the American Pharmacists Association
Yousuf, Seema; Atif, Fahim; Sayeed, Iqbal; Tang, Huiling; Wang, Jun; Stein, Donald G
2015-01-01
Most pre-clinical stroke studies address the acute phase after injury, with less attention to long-term effects of injury, treatment, and experimental testing itself. We addressed these questions: 1) Will functional deficits persist up to 8 weeks following transient stroke in older animals? 2) Will functional deficits resolve spontaneously, with time and/or repeated behavioral testing? Male Sprague-Dawley rats (12 months) were pre-trained on behavioral tasks to provide baseline data and then underwent transient middle artery occlusion (tMCAO) or sham surgery. We measured motor, sensory, cognitive and gait impairments over 8 weeks, and the extent of hemispheric brain infarction. One cohort underwent behavioral testing once at 8 weeks post-stroke (LT); a second cohort (RLT) was tested at 3, 6 and 8 weeks post-stroke. Significant deficits were exhibited in all functional outcomes in both cohorts after 8 weeks. We observed some recovery in some behavioral parameters in both cohorts at 8 weeks. Deficits persist for at least 8 weeks after tMCAO. The greater spontaneous recovery seen in the RLT groups suggest that repeated testing did reduce the severity of these stroke-induced impairments. These findings have implications for designing future studies of agents to induce long-term functional recovery following stroke.
Long-term exposure to intranasal oxytocin in a mouse autism model
Bales, K L; Solomon, M; Jacob, S; Crawley, J N; Silverman, J L; Larke, R H; Sahagun, E; Puhger, K R; Pride, M C; Mendoza, S P
2014-01-01
Oxytocin (OT) is a neuropeptide involved in mammalian social behavior. It is currently in clinical trials for the treatment of autism spectrum disorder (ASD). Previous studies in healthy rodents (prairie voles and C57BL/6J mice) have shown that there may be detrimental effects of long-term intranasal administration, raising the questions about safety and efficacy. To investigate the effects of OT on the aspects of ASD phenotype, we conducted the first study of chronic intranasal OT in a well-validated mouse model of autism, the BTBR T+ Itpr3tf/J inbred strain (BTBR), which displays low sociability and high repetitive behaviors. BTBR and C57BL/6J (B6) mice (N=94) were administered 0.8 IU/kg of OT intranasally, daily for 30 days, starting on day 21. We ran a well-characterized set of behavioral tasks relevant to diagnostic and associated symptoms of autism, including juvenile reciprocal social interactions, three-chambered social approach, open-field exploratory activity, repetitive self-grooming and fear-conditioned learning and memory, some during and some post treatment. Intranasal OT did not improve autism-relevant behaviors in BTBR, except for female sniffing in the three-chambered social interaction test. Male saline-treated BTBR mice showed increased interest in a novel mouse, both in chamber time and sniffing time, whereas OT-treated male BTBR mice showed a preference for the novel mouse in sniffing time only. No deleterious effects of OT were detected in either B6 or BTBR mice, except possibly for the lack of a preference for the novel mouse's chamber in OT-treated male BTBR mice. These results highlight the complexity inherent in understanding the effects of OT on behavior. Future investigations of chronic intranasal OT should include a wider dose range and early developmental time points in both healthy rodents and ASD models to affirm the efficacy and safety of OT. PMID:25386957
Effect of Short- and Long-Term Play Therapy Services on Teacher-Child Relationship Stress
ERIC Educational Resources Information Center
Ray, Dee C.; Henson, Robin K.; Schottelkorb, April A.; Brown, April Garofano; Muro, Joel
2008-01-01
The purpose of the present study was to explore the effect of both short- and long term Child-Centered Play Therapy on teacher-student relationship stress. Teachers identified 58 students exhibiting emotional and behavioral difficulties who were randomly assigned to one of two treatment groups. Students in the short-term intensive play therapy…
Long-term psychosocial outcomes among bereaved siblings of children with cancer
Rosenberg, Abby R.; Postier, Andrea; Osenga, Kaci; Kreicbergs, Ulrika; Neville, Bridget; Dussel, Veronica; Wolfe, Joanne
2014-01-01
Context The death of a child from cancer affects the entire family. Little is known about the long-term psychosocial outcomes of bereaved siblings. Objectives To describe: (1) the prevalence of risky health-behaviors, psychological distress, and social support among bereaved siblings; (2) potentially modifiable factors associated with poor outcomes. Methods Bereaved siblings were eligible for this dual-center, cross-sectional, survey-based study if they were ≥16 years-old and their parents had enrolled in one of three prior studies about caring for children with cancer at end of life. Linear regression models identified associations between personal perspectives before, during, and after the family's cancer experience and outcomes (health-behaviors, psychological distress, and social support). Results Fifty-eight siblings completed surveys (62% response rate). They were approximately 12 years bereaved, with a mean age of 26 years at the time of the survey (SD=7.8). Anxiety, depression, and illicit substance use increased during the year following their brother/sister's death, but then returned to baseline. Siblings who reported dissatisfaction with communication, poor preparation for death, missed opportunities to say “goodbye,” and/or a perceived negative impact of the cancer experience on relationships tended to have higher distress and lower social support scores (p<0.001-0.031). Almost all siblings reported their loss still affected them; half stated the experience impacted current educational and career goals. Conclusion How siblings experience the death of a child with cancer may impact their long-term psychosocial well-being. Sibling-directed communication and concurrent supportive care during the cancer experience and the year following sibling death may mitigate poor long-term outcomes. PMID:24880001
Long-term psychosocial outcomes among bereaved siblings of children with cancer.
Rosenberg, Abby R; Postier, Andrea; Osenga, Kaci; Kreicbergs, Ulrika; Neville, Bridget; Dussel, Veronica; Wolfe, Joanne
2015-01-01
The death of a child from cancer affects the entire family. Little is known about the long-term psychosocial outcomes of bereaved siblings. To describe 1) the prevalence of risky health behaviors, psychological distress, and social support among bereaved siblings and 2) potentially modifiable factors associated with poor outcomes. Bereaved siblings were eligible for this dual-center, cross-sectional, survey-based study if they were 16 years or older and their parents had enrolled in one of three prior studies about caring for children with cancer at the end of life. Linear regression models identified associations between personal perspectives before, during, and after the family's cancer experience and outcomes (health behaviors, psychological distress, and social support). Fifty-eight siblings completed surveys (62% response rate). They were approximately 12 years bereaved, with a mean age of 26 years at the time of the survey (SD 7.8). Anxiety, depression, and illicit substance use increased during the year after their brother/sister's death but then returned to baseline. Siblings who reported dissatisfaction with communication, poor preparation for death, missed opportunities to say goodbye, and/or a perceived negative impact of the cancer experience on relationships tended to have higher distress and lower social support scores (P < 0.001-0.031). Almost all siblings reported that their loss still affected them; half stated that the experience impacted current educational and career goals. How siblings experience the death of a child with cancer may impact their long-term psychosocial well-being. Sibling-directed communication and concurrent supportive care during the cancer experience and the year after the sibling death may mitigate poor long-term outcomes. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Morena, Maria; Berardi, Andrea; Peloso, Andrea; Valeri, Daniela; Palmery, Maura; Trezza, Viviana; Schelling, Gustav; Campolongo, Patrizia
2017-06-30
Intensive Care Unit (ICU) or emergency care patients, exposed to traumatic events, are at increased risk for Post-Traumatic Stress Disorder (PTSD) development. Commonly used sedative/anesthetic agents can interfere with the mechanisms of memory formation, exacerbating or attenuating the memory for the traumatic event, and subsequently promote or reduce the risk of PTSD development. Here, we evaluated the effects of ketamine, dexmedetomidine and propofol on fear memory consolidation and subsequent cognitive and emotional alterations related to traumatic stress exposure. Immediately following an inhibitory avoidance training, rats were intraperitoneally injected with ketamine (100-125mg/kg), dexmedetomidine (0.3-0.4mg/kg) or their vehicle and tested for 48h memory retention. Furthermore, the effects of ketamine (125mg/kg), dexmedetomidine (0.4mg/kg), propofol (300mg/kg) or their vehicle on long-term memory and social interaction were evaluated two weeks after drug injection in a rat PTSD model. Ketamine anesthesia increased memory retention without altering the traumatic memory strength in the PTSD model. However, ketamine induced a long-term reduction of social behavior. Conversely, dexmedetomidine markedly impaired memory retention, without affecting long-lasting cognitive or emotional behaviors in the PTSD model. We have previously shown that propofol anesthesia enhanced 48h memory retention. Here, we found that propofol induced an enduring traumatic memory enhancement and anxiogenic effects in the PTSD model. These findings provide new evidence for clinical studies showing that the use of ketamine or propofol anesthesia in emergency care and ICU might be more likely to promote the development of PTSD, while dexmedetomidine might have prophylactic effects. Copyright © 2017 Elsevier B.V. All rights reserved.
Meunier, Sophie; Coulombe, Simon; Beaulieu, Marie-Dominique; Côté, José; Lespérance, François; Chiasson, Jean-Louis; Bherer, Louis; Lambert, Jean; Houle, Janie
2016-11-01
The study's aim was to test prospective associations between information, motivation, and behavioral skills (IMB model) and self-care behaviors (diet, exercise, and blood glucose testing) among patients with type 2 diabetes. 295 participants were surveyed one (T1), six (T2), and 12 (T3) months after a diabetes course. Cross-lagged panel analyses were performed to test unidirectional and bidirectional relationships between IMB model variables and self-care behaviors. Blood-glucose testing at T1 was positively related to information at T2, which in turn was positively related to blood-glucose testing at T3. Controlled motivation at T1 was positively related to exercise at T2. Autonomous motivation at T2 was positively associated with exercise at T3. There was a positive bidirectional relationship across time between behavioral skills and general diet. Patterns of prospective associations between IMB model variables and diabetes self-care depend on the self-care behavior considered. This model offers an interesting framework for examining how diabetes self-care behaviors evolve. Diabetes education programs should provide information about current health status and promote experiential learning to help patients realize the impact of their behaviors on glycemic control; should foster autonomous motivation for long-term change; and should build on patients' strengths and skills. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Soliman, Moomen; Eldyasti, Ahmed
2017-06-01
Recently, partial nitrification has been adopted widely either for the nitrite shunt process or intermediate nitrite generation step for the Anammox process. However, partial nitrification has been hindered by the complexity of maintaining stable nitrite accumulation at high nitrogen loading rates (NLR) which affect the feasibility of the process for high nitrogen content wastewater. Thus, the operational data of a lab scale SBR performing complete partial nitrification as a first step of nitrite shunt process at NLRs of 0.3-1.2kg/(m 3 d) have been used to calibrate and validate a process model developed using BioWin® in order to describe the long-term dynamic behavior of the SBR. Moreover, an identifiability analysis step has been introduced to the calibration protocol to eliminate the needs of the respirometric analysis for SBR models. The calibrated model was able to predict accurately the daily effluent ammonia, nitrate, nitrite, alkalinity concentrations and pH during all different operational conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Analyzing the Long Term Cohesive Effect of Sector Specific Driving Forces.
Berman, Yonatan; Ben-Jacob, Eshel; Zhang, Xin; Shapira, Yoash
2016-01-01
Financial markets are partially composed of sectors dominated by external driving forces, such as commodity prices, infrastructure and other indices. We characterize the statistical properties of such sectors and present a novel model for the coupling of the stock prices and their dominating driving forces, inspired by mean reverting stochastic processes. Using the model we were able to explain the market sectors' long term behavior and estimate the coupling strength between stocks in financial markets and the sector specific driving forces. Notably, the analysis was successfully applied to the shipping market, in which the Baltic dry index (BDI), an assessment of the price of transporting the major raw materials by sea, influences the shipping financial market. We also present the analysis of other sectors-the gold mining market and the food production market, for which the model was also successfully applied. The model can serve as a general tool for characterizing the coupling between external forces and affected financial variables and therefore for estimating the risk in sectors and their vulnerability to external stress.
Analyzing the Long Term Cohesive Effect of Sector Specific Driving Forces
Berman, Yonatan; Zhang, Xin; Shapira, Yoash
2016-01-01
Financial markets are partially composed of sectors dominated by external driving forces, such as commodity prices, infrastructure and other indices. We characterize the statistical properties of such sectors and present a novel model for the coupling of the stock prices and their dominating driving forces, inspired by mean reverting stochastic processes. Using the model we were able to explain the market sectors’ long term behavior and estimate the coupling strength between stocks in financial markets and the sector specific driving forces. Notably, the analysis was successfully applied to the shipping market, in which the Baltic dry index (BDI), an assessment of the price of transporting the major raw materials by sea, influences the shipping financial market. We also present the analysis of other sectors—the gold mining market and the food production market, for which the model was also successfully applied. The model can serve as a general tool for characterizing the coupling between external forces and affected financial variables and therefore for estimating the risk in sectors and their vulnerability to external stress. PMID:27031230
Implementing unpredictability in feeding enrichment for Malayan sun bears (Helarctos malayanus).
Schneider, Marion; Nogge, Gunther; Kolter, Lydia
2014-01-01
Bears in the wild spend large proportions of time in foraging activities. In zoos their time budgets differ markedly from those of their wild counterparts. Feeding enrichment has been documented to increase foraging behavior and to reduce stereotypies. But in general these procedures have no long-term effects and result in habituation. As can be expected by the predictions of the optimal foraging theory, foraging activities are restricted as long as the availability of food is predictable. To quantify the effect of spatial unpredictability, three feeding methods have been designed to stimulate functional foraging behavior in captive Malayan sun bears in the long-term. In order to examine if habituation occurs, the most effective method was tested for 12 consecutive days. Activities of four adult sun bears at the Cologne Zoo were recorded by focal animal recording of foraging behaviors and time sampling of activities for a total of 360 hr. Implementing unpredictability significantly increased the time the bears spent foraging and led to a higher diversity of foraging behaviors. The effects lasted throughout the entire day and no habituation occurred in the course of 12 consecutive days. The study shows how functional species typical behavior in captive Malayan sun bears can be stimulated in the long-term by simulating natural characteristics of food availability. © 2014 Wiley Periodicals, Inc.
The Science of Sustaining Health Behavior Change: The Health Maintenance Consortium
Ory, Marcia G.; Smith, Matthew Lee; Mier, Nelda; Wernicke, Meghan M.
2013-01-01
Objective The Health Maintenance Consortium (HMC) is a multisite Grantee Consortium funded by the National Institutes of Health from 2004–2009. The goal of HMC is to enhance understanding of the long-term maintenance of behavior change, as well as effective strategies for achieving sustainable health promotion and disease prevention. Methods This introductory research synthesis prepared by the Resource Center gives context to this theme issue by providing an overview of the HMC and the articles in this journal. Results It explores the contributions to our conceptualization of behavior change processes and intervention strategies, the trajectory of effectiveness of behavioral and social interventions, and factors influencing the long-term maintenance of behavioral and social interventions. Conclusions Future directions for furthering the science of maintaining behavior change and reducing the gaps between research and practice are recommended. PMID:20604691
NASA Astrophysics Data System (ADS)
Sheer, D. P.
2011-12-01
Economics provides a model for describing human behavior applied to the management of water resources, but that model assumes, among other things, that managers have a way of directly relating immediate actions to long-term economic outcomes. This is rarely the case in water resources problems where uncertainty has significant impacts on the effectiveness of management strategies and where the management objectives are very difficult to commensurate. The difficulty in using economics is even greater in multiparty disputes, where each party has a different relative value for each of the management objectives, and many of the management objectives are shared. A three step approach to collaborative decision making can overcome these difficulties. The first step involves creating science based performance measures and evaluation tools to estimate the effect of alternative management strategies on each of the non-commensurate objectives. The second step involves developing short-term surrogate operating objectives that implicitly deal with all of the aspects of the long term uncertainty. Management that continually "optimizes" the short-term objectives subject to physical and other constraints that change through time can be characterized as Rule Driven Multi-Objective Management (RDMOM). RDMOM strategies are then tested in simulation models to provide the basis for evaluating performance measures. Participants in the collaborative process then engage in multiparty discussions that create new alternatives, and "barter" a deal. RDMOM does not assume that managers fully understand the link between current actions and long term goals. Rather, it assumes that managers operate to achieve short-term surrogate objectives which they believe will achieve an appropriate balance of both short and long-term incommensurable benefits. A reservoir rule curve is a simple, but often not particularly effective, example of the real-world implementation of RDMOM. Water managers find they can easily describe and explain their written and unwritten protocols using the RDMOM, and that the use of short-term surrogates is both intellectually appealing and pragmatic. The identification of operating targets as short-term surrogates leads naturally to a critical discussion of long-term objectives, and to the development of performance measures for the long-term objectives. The transparency and practical feasibility RDMOM based strategies is often crucial to the success of collaborative efforts. Complex disputes in the Delaware and Susquehanna Basins, the Everglades and Lower East Coast South Florida, Southern Nevada, Washington DC and many others have been resolved using RDMOM strategies.
Long-term memory and volatility clustering in high-frequency price changes
NASA Astrophysics Data System (ADS)
oh, Gabjin; Kim, Seunghwan; Eom, Cheoljun
2008-02-01
We studied the long-term memory in diverse stock market indices and foreign exchange rates using Detrended Fluctuation Analysis (DFA). For all high-frequency market data studied, no significant long-term memory property was detected in the return series, while a strong long-term memory property was found in the volatility time series. The possible causes of the long-term memory property were investigated using the return data filtered by the AR(1) model, reflecting the short-term memory property, the GARCH(1,1) model, reflecting the volatility clustering property, and the FIGARCH model, reflecting the long-term memory property of the volatility time series. The memory effect in the AR(1) filtered return and volatility time series remained unchanged, while the long-term memory property diminished significantly in the volatility series of the GARCH(1,1) filtered data. Notably, there is no long-term memory property, when we eliminate the long-term memory property of volatility by the FIGARCH model. For all data used, although the Hurst exponents of the volatility time series changed considerably over time, those of the time series with the volatility clustering effect removed diminish significantly. Our results imply that the long-term memory property of the volatility time series can be attributed to the volatility clustering observed in the financial time series.
Bohon, Lisa M.; Cotter, Kelly A.; Kravitz, Richard L.; Cello, Philip C.; Garcia, Erik Fernandez y
2016-01-01
Between 9.5% and 31.3% of College students suffer from depression1, 2. Universities need to understand the factors that relate to care-seeking behavior. Objective Across 3 studies, to relate attitude, social norms, and perceived behavioral control to intention to seek mental health services, and to investigate barriers to care-seeking. Participants University college students (N = 845, 64% female, 26% male, and 10% unspecified). Method New measures were created in studies 1 and 2, and were examined using structural equation modeling in study 3. Results Partially consistent with the Theory of Planned Behavior3, a model with an excellent fit revealed that more positive attitudes about care and higher perceived behavioral control directly predicted higher intention to seek mental health services. Conclusions Educating college students about mental health disorders and treatments, enhancing knowledge about available services, and addressing limited access to long-term care might improve treatment rates for students suffering from depression. PMID:27386898
Correlation between the oxide impedance and corrosion behavior of Zr-Nb-Sn-Fe-Cu alloys
NASA Astrophysics Data System (ADS)
Park, Sang-Yoon; Lee, Myung-Ho; Jeong, Yong-Hwan; Jung, Youn-Ho
2004-12-01
The correlation between the oxide impedance and corrosion behavior of two series of Zr-Nb-Sn-Fe-Cu alloys was evaluated. Corrosion tests were performed in a 70 ppm LiOH aqueous solution at 360°C for 300 days. The results of the corrosion tests revealed that the corrosion behavior of the alloys depended on the Nb and Sn content. The impedance characteristics for the pre- and post-transition oxide layers formed on the surface of the alloys were investigated in sulfuric acid at room temperature. From the results, a pertinent equivalent circuit model was preferably established, explaining the properties of double oxide layers. The impedance of the oxide layers correlated with the corrosion behavior; better corrosion resistance always showed higher electric resistance for the inner layers. It is thus concluded that a pertinent equivalent circuit model would be useful for evaluating the long-term corrosion behavior of Zr-Nb-Sn-Fe-Cu alloys.
Relative phase asynchrony and long-range correlation of long-term solar magnetic activity
NASA Astrophysics Data System (ADS)
Deng, Linhua
2017-07-01
Statistical signal processing is one of the most important tasks in a large amount of areas of scientific studies, such as astrophysics, geophysics, and space physics. Phase recurrence analysis and long-range persistence are the two dynamical structures of the underlying processes for the given natural phenomenon. Linear and nonlinear time series analysis approaches (cross-correlation analysis, cross-recurrence plot, wavelet coherent transform, and Hurst analysis) are combined to investigate the relative phase interconnection and long-range correlation between solar activity and geomagnetic activity for the time interval from 1932 January to 2017 January. The following prominent results are found: (1) geomagnetic activity lags behind sunspot numbers with a phase shift of 21 months, and they have a high level of asynchronous behavior; (2) their relative phase interconnections are in phase for the periodic scales during 8-16 years, but have a mixing behavior for the periodic belts below 8 years; (3) both sunspot numbers and geomagnetic activity can not be regarded as a stochastic phenomenon because their dynamical behaviors display a long-term correlation and a fractal nature. We believe that the presented conclusions could provide further information on understanding the dynamical coupling of solar dynamo process with geomagnetic activity variation, and the crucial role of solar and geomagnetic activity in the long-term climate change.
Dilatancy Criteria for Salt Cavern Design: A Comparison Between Stress- and Strain-Based Approaches
NASA Astrophysics Data System (ADS)
Labaune, P.; Rouabhi, A.; Tijani, M.; Blanco-Martín, L.; You, T.
2018-02-01
This paper presents a new approach for salt cavern design, based on the use of the onset of dilatancy as a design threshold. In the proposed approach, a rheological model that includes dilatancy at the constitutive level is developed, and a strain-based dilatancy criterion is defined. As compared to classical design methods that consist in simulating cavern behavior through creep laws (fitted on long-term tests) and then using a criterion (derived from short-terms tests or experience) to determine the stability of the excavation, the proposed approach is consistent both with short- and long-term conditions. The new strain-based dilatancy criterion is compared to a stress-based dilatancy criterion through numerical simulations of salt caverns under cyclic loading conditions. The dilatancy zones predicted by the strain-based criterion are larger than the ones predicted by the stress-based criteria, which is conservative yet constructive for design purposes.
Mental Health, Behavioral and Developmental Issues for Youth in Foster Care.
Deutsch, Stephanie A; Lynch, Amy; Zlotnik, Sarah; Matone, Meredith; Kreider, Amanda; Noonan, Kathleen
2015-10-01
Youth in foster care represent a unique population with complex mental and behavioral health, social-emotional, and developmental needs. For this population with special healthcare needs, the risk for adverse long-term outcomes great if needs go unaddressed or inadequately addressed while in placement. Although outcomes are malleable and effective interventions exist, there are barriers to optimal healthcare delivery. The general pediatrician as advocate is paramount to improve long-term outcomes. Copyright © 2015 Mosby, Inc. All rights reserved.
Long-Term Care Eligibility Criteria for People with Alzheimer's Disease
Fox, Patrick; Maslow, Katie; Zhang, Xiulan
1999-01-01
Long-term care (LTC) eligibility criteria are applied to a sample of 8,437 people with dementia enrolled in the Medicare Alzheimer's Disease Demonstration. The authors find that mental-status-test cutoff points substantially affect the pool of potential beneficiaries. Functional criteria alone leave out people with relatively severe dementia and with behavioral problems. It is therefore important to consider both behavioral and mental-status-test criteria in establishing eligibility for community-based services for people with dementia. PMID:11482125
Near-Term Actions to Address Long-Term Climate Risk
NASA Astrophysics Data System (ADS)
Lempert, R. J.
2014-12-01
Addressing climate change requires effective long-term policy making, which occurs when reflecting on potential events decades or more in the future causes policy makers to choose near-term actions different than those they would otherwise pursue. Contrary to some expectations, policy makers do sometimes make such long-term decisions, but not as commonly and successfully as climate change may require. In recent years however, the new capabilities of analytic decision support tools, combined with improved understanding of cognitive and organizational behaviors, has significantly improved the methods available for organizations to manage longer-term climate risks. In particular, these tools allow decision makers to understand what near-term actions consistently contribute to achieving both short- and long-term societal goals, even in the face of deep uncertainty regarding the long-term future. This talk will describe applications of these approaches for infrastructure, water, and flood risk management planning, as well as studies of how near-term choices about policy architectures can affect long-term greenhouse gas emission reduction pathways.
Semple, Bridgette D; Trivedi, Alpa; Gimlin, Kayleen; Noble-Haeusslein, Linda J
2015-02-01
While neutrophil elastase (NE), released by activated neutrophils, is a key mediator of secondary pathogenesis in adult models of brain ischemia and spinal cord injury, no studies to date have examined this protease in the context of the injured immature brain, where there is notable vulnerability resulting from inadequate antioxidant reserves and prolonged exposure to infiltrating neutrophils. We thus reasoned that NE may be a key determinant of secondary pathogenesis, and as such, adversely influence long-term neurological recovery. To address this hypothesis, wild-type (WT) and NE knockout (KO) mice were subjected to a controlled cortical impact at post-natal day 21, approximating a toddler-aged child. To determine if NE is required for neutrophil infiltration into the injured brain, and whether this protease contributes to vasogenic edema, we quantified neutrophil numbers and measured water content in the brains of each of these genotypes. While leukocyte trafficking was indistinguishable between genotypes, vasogenic edema was markedly attenuated in the NE KO. To determine if early pathogenesis is dependent on NE, indices of cell death (TUNEL and activated caspase-3) were quantified across genotypes. NE KO mice showed a reduction in these markers of cell death in the injured hippocampus, which corresponded to greater preservation of neuronal integrity as well as reduced expression of heme oxygenase-1, a marker of oxidative stress. WT mice, treated with a competitive inhibitor of NE at 2, 6 and 12h post-injury, likewise showed a reduction in cell death and oxidative stress compared to vehicle-treated controls. We next examined the long-term behavioral and structural consequences of NE deficiency. NE KO mice showed an improvement in long-term spatial memory retention and amelioration of injury-induced hyperactivity. However, volumetric and stereological analyses found comparable tissue loss in the injured cortex and hippocampus independent of genotype. Further, WT mice treated acutely with the NE inhibitor showed no long-term behavioral or structural improvements. Together, these findings validate the central role of NE in both acute pathogenesis and chronic functional recovery, and support future exploration of the therapeutic window, taking into account the prolonged period of neutrophil trafficking into the injured immature brain. Copyright © 2014 Elsevier Inc. All rights reserved.
Semple, Bridgette D; Trivedi, Alpa; Gimlin, Kayleen; Noble-Haeusslein, Linda J
2014-01-01
While neutrophil elastase (NE), released by activated neutrophils, is a key mediator of secondary pathogenesis in adult models of brain ischemia and spinal cord injury, no studies to date have examined this protease in the context of the injured immature brain, where there is notable vulnerability resulting from inadequate antioxidant reserves and prolonged exposure to infiltrating neutrophils. We thus reasoned that NE may be a key determinant of secondary pathogenesis, and as such, adversely influence long-term neurological recovery. To address this hypothesis, wild-type (WT) and NE knockout (KO) mice were subjected to a controlled cortical impact at post-natal day 21, approximating a toddler-aged child. To determine if NE is required for neutrophil infiltration into the injured brain, and whether this protease contributes to vasogenic edema, we quantified neutrophil numbers and measured water content in the brains of each of these genotypes. While leukocyte trafficking was indistinguishable between genotypes, vasogenic edema was markedly attenuated in the NE KO. To determine if early pathogenesis is dependent on NE, indices of cell death (TUNEL and activated caspase-3) were quantified across genotypes. NE KO mice showed a reduction in these markers of cell death in the injured hippocampus, which corresponded to greater preservation of neuronal integrity as well as reduced expression of heme oxygenase-1, a marker of oxidative stress. WT mice, treated with a competitive inhibitor of NE at 2, 6 and 12 h post-injury, likewise showed a reduction in cell death and oxidative stress compared to vehicle-treated controls. We next examined the long-term behavioral and structural consequences of NE deficiency. NE KO mice showed an improvement in long-term spatial memory retention and amelioration of injury-induced hyperactivity. However, volumetric and stereological analyses found comparable tissue loss in the injured cortex and hippocampus independent of genotype. Further, WT mice treated acutely with the NE inhibitor showed no long-term behavioral or structural improvements. Together, these findings validate the central role of NE in both acute pathogenesis and chronic functional recovery, and support future exploration of the therapeutic window, taking into account the prolonged period of neutrophil trafficking into the injured immature brain. PMID:25497734
Obenhaus, Horst A; Rozov, Andrei; Bertocchi, Ilaria; Tang, Wannan; Kirsch, Joachim; Betz, Heinrich; Sprengel, Rolf
2016-01-01
The causal interrogation of neuronal networks involved in specific behaviors requires the spatially and temporally controlled modulation of neuronal activity. For long-term manipulation of neuronal activity, chemogenetic tools provide a reasonable alternative to short-term optogenetic approaches. Here we show that virus mediated gene transfer of the ivermectin (IVM) activated glycine receptor mutant GlyRα1 (AG) can be used for the selective and reversible silencing of specific neuronal networks in mice. In the striatum, dorsal hippocampus, and olfactory bulb, GlyRα1 (AG) promoted IVM dependent effects in representative behavioral assays. Moreover, GlyRα1 (AG) mediated silencing had a strong and reversible impact on neuronal ensemble activity and c-Fos activation in the olfactory bulb. Together our results demonstrate that long-term, reversible and re-inducible neuronal silencing via GlyRα1 (AG) is a promising tool for the interrogation of network mechanisms underlying the control of behavior and memory formation.
Jentsch, J D; Roth, R H
1999-03-01
Administration of noncompetitive NMDA/glutamate receptor antagonists, such as phencyclidine (PCP) and ketamine, to humans induces a broad range of schizophrenic-like symptomatology, findings that have contributed to a hypoglutamatergic hypothesis of schizophrenia. Moreover, a history of experimental investigations of the effects of these drugs in animals suggests that NMDA receptor antagonists may model some behavioral symptoms of schizophrenia in nonhuman subjects. In this review, the usefulness of PCP administration as a potential animal model of schizophrenia is considered. To support the contention that NMDA receptor antagonist administration represents a viable model of schizophrenia, the behavioral and neurobiological effects of these drugs are discussed, especially with regard to differing profiles following single-dose and long-term exposure. The neurochemical effects of NMDA receptor antagonist administration are argued to support a neurobiological hypothesis of schizophrenia, which includes pathophysiology within several neurotransmitter systems, manifested in behavioral pathology. Future directions for the application of NMDA receptor antagonist models of schizophrenia to preclinical and pathophysiological research are offered.
Aging behavior of near atmospheric N2 ambient sputtered/patterned Au IR absorber thin films
NASA Astrophysics Data System (ADS)
Gaur, Surender P.; Kothari, Prateek; Rangra, Kamaljit; Kumar, Dinesh
2018-03-01
Near atmospheric N2 ambient sputtered Au thin films exhibit significant spectral absorptivity over medium to long wave infrared radiations. Thin films were found adequately robust for micropatterning using conventional photolithography and metal lift off processes. Since long term spectral absorptivity is major practical concern for Au blacks, this paper reports on aging behavior of near atmospheric Ar and Ar + N2 (1:1) ambient sputtered infrared absorber Au thin films. Comparative analysis on electrical, morphological and spectral absorption behavior of twenty-five weeks room temperature/vacuum aged Au infrared absorber thin films is performed. The Ar and Ar + N2 ambient sputtered Au thing films have shown anticipated consistency in their physical, electrical and spectral properties regardless the long term aging in this work.
Dion, Kenneth L
2004-07-01
The issues of interpersonal and group processes in long-term spacecrews from the perspectives of social and organizational psychology are considered here. A contrast between the Amundsen vs. Scott expeditions to the South Pole 90 yrs. ago highlights the importance of personnel selection and attention to interpersonal and group dynamics in expeditions to extreme and dangerous environments, such as long-term spaceflights today. Under the rubric of personnel selection, some further psychological "select-in" and "select-out" criteria are suggested, among them implicit measures of human motivation, intergroup attitudes ("implicit" and "explicit" measures of prejudice, social dominance orientation, and right-wing authoritarianism), attachment styles, and dispositional hardiness. The situational interview and the idea of "selection for teams," drawn from current advances in organizational psychology, are recommended for selecting members for future spacecrews. Under the rubrics of interpersonal and group processes, the social relations model is introduced as a technique for modeling and understanding interdependence among spacecrew members and partialling out variance in behavioral and perceptual data into actor/perceiver, partner/target, and relationship components. Group cohesion as a multidimensional construct is introduced, along with a consideration of the groupthink phenomenon and its controversial link to cohesion. Group composition issues are raised with examples concerning cultural heterogeneity and gender composition. Cultural value dimensions, especially power distance and individual-collectivism, should be taken into account at both societal and psychological levels in long-term space missions. Finally, intergroup processes and language issues in crews are addressed. The recategorization induction from the common ingroup identity model is recommended as a possible intervention for overcoming and inhibiting intergroup biases within spacecrews and between space- and groundcrews.
Modeling the Sustainability of a Ceramic Water Filter Intervention
Mellor, Jonathan; Abebe, Lydia; Ehdaie, Beeta; Dillingham, Rebecca; Smith, James
2014-01-01
Ceramic water filters (CWFs) are a point-of-use water treatment technology that has shown promise in preventing early childhood diarrhea (ECD) in resource-limited settings. Despite this promise, some researchers have questioned their ability to reduce ECD incidences over the long term since most effectiveness trials conducted to date are less than one year in duration limiting their ability to assess long-term sustainability factors. Most trials also suffer from lack of blinding making them potentially biased. This study uses an agent-based model (ABM) to explore factors related to the long-term sustainability of CWFs in preventing ECD and was based on a three year longitudinal field study. Factors such as filter user compliance, microbial removal effectiveness, filter cleaning and compliance declines were explored. Modeled results indicate that broadly defined human behaviors like compliance and declining microbial effectiveness due to improper maintenance are primary drivers of the outcome metrics of household drinking water quality and ECD rates. The model predicts that a ceramic filter intervention can reduce ECD incidence amongst under two year old children by 41.3%. However, after three years, the average filter is almost entirely ineffective at reducing ECD incidence due to declining filter microbial removal effectiveness resulting from improper maintenance. The model predicts very low ECD rates are possible if compliance rates are 80-90%, filter log reduction efficiency is 3 or greater and there are minimal long-term compliance declines. Cleaning filters at least once every 4 months makes it more likely to achieve very low ECD rates as does the availability of replacement filters for purchase. These results help to understand the heterogeneity seen in previous intervention-control trials and reemphasize the need for researchers to accurately measure confounding variables and ensure that field trials are at least 2-3 years in duration. In summary, the CWF can be a highly effective tool in the fight against ECD, but every effort should be made by implementing agencies to ensure consistent use and maintenance. PMID:24355289
The Scorpion An ideal animal model to study long-term microgravity effects on circadian rhythms
NASA Astrophysics Data System (ADS)
Riewe, Pascal C.; Horn, Eberhard R.
2000-01-01
The temporal pattern of light and darkness is basic for the coordination of circadian rhythms and establishment of homoeostasis. The 24th frequency of zeitgebers is probably a function of the Earth's rotation. The only way to eliminate its influence on organisms is to study their behavior in space because the reduced day length during orbiting the Earth might disrupt synchronizing mechanisms based on the 24th rhythm. The stability of microgravity induced disturbances of synchronization as well as the extent of adaptation of different physiological processes to this novel environment can only be studied during long-term exposures to microgravity, i.e., on the International Space Station. Biological studies within the long-term domain on ISS demand the use of experimental models which can be exposed to automatic handling of measurements and which need less or no nutritional care. Scorpions offer these features. We describe a fully automatic recording device for the simultaneous collection of data regarding the sensorimotor system and homoeostatic mechanisms. In particular, we record sensitivity changes of the eyes, motor activity and heart beat and/or respiratory activity. The advantage of the scorpion model is supported by the fact that data can be recorded preflight, inflight and postflight from the same animal. With this animal model, basic insights will be obtained about the de-coupling of circadian rhythms of multiple oscillators and their adaptation to the entraining zeitgeber periodicity during exposure to microgravity for at least three biological parameters recorded simultaneously. .
Long-term Accretion Variations of the Magnetic Cataclysmic Variable Star QQ Vulpecula
NASA Astrophysics Data System (ADS)
Cooper Rose, Sanaea; Kafka, Stella; Jorgenson, Regina; Carr, Derrick; Childs, Francesca; Christenson, Holly; Karim, Md. Tanveer; Konchady, Tarini; Walker, Gary E.; Honeycutt, R. K.
2017-01-01
Magnetic cataclysmic variable stars have brightness variations that repeat with each revolution of the two stars about the center of mass of the system. However, in the case of QQ Vulpecula (QQ Vul), this brightness variation pattern changes in the long term. This study makes use of two decades worth of data from the Roboscope Telescope as well as data from the American Association of Variable Star Observers (AAVSO) database to examine the long-term evolution of QQ Vul’s phase curves. Nightly observations using the Maria Mitchell Association's Vestal and Loines Observatories supplemented this analysis by clarifying short-term brightness variation. The long-term data was divided into four commonly observed behavioral types ranging from a double peaked curve of ~15.5 magnitude to a ~15.0 magnitude curve that had a primary minimum and a slow, linear rise in brightness in place of the secondary minimum. The nightly data kept within the confines of these categories, though the secondary minimum in the nightly data never vanished. No periodicity was found in the long-term variations. The model often invoked to explain the double peaked curve consists of single pole accretion in which a partial self-eclipse causes the secondary minimum and cyclotron beaming causes the primary minimum. However, the long-term variation may indicate a changing accretion rate, which may manifest itself in changes to the shape, size, or location of the accretion spot on the white dwarf such that it lessens or removes the secondary minimum. This project was supported by the NSF REU grant AST-1358980, the Massachusetts Space Grant, and the Nantucket Maria Mitchell Association.
Incorporating the eruptive history in a stochastic model for volcanic eruptions
NASA Astrophysics Data System (ADS)
Bebbington, Mark
2008-08-01
We show how a stochastic version of a general load-and-discharge model for volcanic eruptions can be implemented. The model tracks the history of the volcano through a quantity proportional to stored magma volume. Thus large eruptions can influence the activity rate for a considerable time following, rather than only the next repose as in the time-predictable model. The model can be fitted to data using point-process methods. Applied to flank eruptions of Mount Etna, it exhibits possible long-term quasi-cyclic behavior, and to Mauna Loa, a long-term decrease in activity. An extension to multiple interacting sources is outlined, which may be different eruption styles or locations, or different volcanoes. This can be used to identify an 'average interaction' between the sources. We find significant evidence that summit eruptions of Mount Etna are dependent on preceding flank eruptions, with both flank and summit eruptions being triggered by the other type. Fitted to Mauna Loa and Kilauea, the model had a marginally significant relationship between eruptions of Mauna Loa and Kilauea, consistent with the invasion of the latter's plumbing system by magma from the former.
Veale, David; Miles, Sarah; Anson, Martin
2015-11-01
There is some evidence for the efficacy of cognitive behavior therapy (CBT) for body dysmorphic disorder (BDD) after 1 to 6months but none in the long term. The aim of this study was to follow up the participants in a randomized controlled trial of CBT versus anxiety management to determine whether or not the treatment gains were maintained over time. Thirty of the original 39 participants who had CBT were followed up over 1 to 4years and assessed using a number of clinician and self-report measures, which included the primary outcome measure of the Yale-Brown Obsessive Compulsive Scale modified for BDD. Outcome scores generally maintained over time from end of treatment to long-term follow-up. There was a slight deterioration from n=20 (51.3%) to n=18 (46.2%) who met improvement criteria at long-term follow-up. Eleven (28.2%) were in full remission and 22 (56.4%) were in partial remission. The gains made were generally maintained at long-term follow-up. However, there were a significant number of participants who maintained chronic symptoms after treatment and may need a longer-term or more complex intervention and active medication management. Copyright © 2015. Published by Elsevier Ltd.
Long-term effect of September 11 on the political behavior of victims’ families and neighbors
Hersh, Eitan D.
2013-01-01
This article investigates the long-term effect of September 11, 2001 on the political behaviors of victims’ families and neighbors. Relative to comparable individuals, family members and residential neighbors of victims have become—and have stayed—significantly more active in politics in the last 12 years, and they have become more Republican on account of the terrorist attacks. The method used to demonstrate these findings leverages the random nature of the terrorist attack to estimate a causal effect and exploits new techniques to link multiple, individual-level, governmental databases to measure behavioral change without relying on surveys or aggregate analysis. PMID:24324145
Long-term effect of September 11 on the political behavior of victims' families and neighbors.
Hersh, Eitan D
2013-12-24
This article investigates the long-term effect of September 11, 2001 on the political behaviors of victims' families and neighbors. Relative to comparable individuals, family members and residential neighbors of victims have become--and have stayed--significantly more active in politics in the last 12 years, and they have become more Republican on account of the terrorist attacks. The method used to demonstrate these findings leverages the random nature of the terrorist attack to estimate a causal effect and exploits new techniques to link multiple, individual-level, governmental databases to measure behavioral change without relying on surveys or aggregate analysis.
Cassel, Jean-Christophe; Riegert, Céline; Rutz, Susanne; Koenig, Julie; Rothmaier, Katharina; Cosquer, Brigitte; Lazarus, Christine; Birthelmer, Anja; Jeltsch, Hélène; Jones, Byron C; Jackisch, Rolf
2005-10-01
This study investigated long-term behavioral, neurochemical, and neuropharmacological effects of ethanol-(+/-)-3,4-methylenedioxymethamphetamine (MDMA, ecstasy) combinations. Over 4 consecutive days, male Long-Evans rats received 1.5 g/kg ethanol and/or 10 mg/kg MDMA, or saline. Rectal temperatures were taken in some rats. Starting 4 days after the last injection, we tested working memory, sensory-motor coordination, and anxiety. Subsequently, we measured cortical, striatal, septal, and hippocampal monoamines (last MDMA injection-euthanasia delay: 20 days), or electrically evoked release of serotonin (5-HT) in cortical and hippocampal slices, and its modulation in the presence of CP 93,129 (3-(1,2,5,6-tetrahydropyrid-4-yl)pyrrollo[3,2-b]pyrid-5-one) or methiotepin (last MDMA injection-euthanasia delays: 3-6 weeks). Ethanol attenuated the MDMA-induced hyperthermia, but only on the first day. In the long-term, MDMA reduced 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) content in most brain regions. The behavioral and neurochemical effects of the ethanol-MDMA combination were comparable to those of MDMA alone; sensory-motor coordination was altered after ethanol and/or MDMA. In hippocampal slices from rats given ethanol and MDMA, the CP 93,129-induced inhibition and methiotepin-induced facilitation of 5-HT release were stronger and weaker, respectively, than in the other groups. This is the first study addressing long-term effects of repeated MDMA and EtOH combined treatments in experimental animals. Whereas the drug combination produced the same behavioral and neurochemical effects as MDMA alone, our neuropharmacological results suggest that MDMA-EtOH interactions may have specific long-term consequences on presynaptic modulation of hippocampal 5-HT release, but not necessarily related to MDMA-induced depletion of 5-HT. Thus, it is likely that the psycho(patho)logical problems reported by ecstasy users drinking alcohol are not solely due to the consumption of MDMA.
Adolescent Loss-of-Control Eating and Weight Loss Maintenance After Bariatric Surgery.
Goldschmidt, Andrea B; Khoury, Jane; Jenkins, Todd M; Bond, Dale S; Thomas, J Graham; Utzinger, Linsey M; Zeller, Meg H; Inge, Thomas H; Mitchell, James E
2018-01-01
Loss-of-control (LOC) eating is common in adults undergoing bariatric surgery and is associated with poorer weight outcomes. Its long-term course in adolescent bariatric surgery patients and associations with weight outcomes are unclear. Adolescents ( n = 234; age range = 13-19 years) undergoing bariatric surgery across 5 US sites were assessed for postsurgery follow-up at 6 months and 1, 2, 3, and 4 years. Descriptive statistics and generalized linear mixed models were used to describe the prevalence of LOC eating episodes involving objectively large amounts of food and continuous eating, respectively. Generalized linear mixed models investigated the association of any LOC eating with short- and long-term BMI changes. At baseline, objectively large LOC eating was reported by 15.4% of adolescents, and continuous LOC eating by 27.8% of adolescents. Both forms of LOC eating were significantly lower at all postsurgical time points relative to presurgery (range = 0.5%-14.5%; P s < .05). However, both behaviors gradually increased from 6-month to 4-year follow-up ( P s < .05). Presurgical LOC eating was not related to percent BMI change over follow-up ( P = .79). However, LOC eating at 1-, 2-, and 3-year follow-up was associated with lower percent BMI change from baseline at the next consecutive assessment ( P s < .05). Although presurgical LOC eating was not related to relative weight loss after surgery, postoperative LOC eating may adversely affect long-term weight outcomes. Rates of LOC eating decreased from presurgery to 6-months postsurgery but increased thereafter. Therefore, this behavior may warrant additional empirical and clinical attention. Copyright © 2018 by the American Academy of Pediatrics.
Deploying Server-side File System Monitoring at NERSC
DOE Office of Scientific and Technical Information (OSTI.GOV)
Uselton, Andrew
2009-05-01
The Franklin Cray XT4 at the NERSC center was equipped with the server-side I/O monitoring infrastructure Cerebro/LMT, which is described here in detail. Insights gained from the data produced include a better understanding of instantaneous data rates during file system testing, file system behavior during regular production time, and long-term average behaviors. Information and insights gleaned from this monitoring support efforts to proactively manage the I/O infrastructure on Franklin. A simple model for I/O transactions is introduced and compared with the 250 million observations sent to the LMT database from August 2008 to February 2009.
Multimethod Behavioral Treatment of Long-Term Selective Mutism.
ERIC Educational Resources Information Center
Watson, T. Steuart; Kramer, Jack J.
1992-01-01
Conducted single-subject, experimental research to examine efficacy of treating severe, long-term selective mutism in nine-year-old male using shaping, multiple reinforcers, natural consequences, stimulus fading, and mild aversives. Implemented different treatment regimens in home and school environments. Home intervention resulted in increase in…