Science.gov

Sample records for livia approach nash

  1. Pigeons ("Columba Livia") Approach Nash Equilibrium in Experimental Matching Pennies Competitions

    ERIC Educational Resources Information Center

    Sanabria, Federico; Thrailkill, Eric

    2009-01-01

    The game of Matching Pennies (MP), a simplified version of the more popular Rock, Papers, Scissors, schematically represents competitions between organisms with incentives to predict each other's behavior. Optimal performance in iterated MP competitions involves the production of random choice patterns and the detection of nonrandomness in the…

  2. Exhaustible resources and market structure in world oil: a Nash-Cournot approach

    SciTech Connect

    Ortiz, C.J.

    1983-01-01

    Most studies in the economic literature suggested the 1974-1978 world oil price structure as nearly compatible with optimum OPEC profits. Since 1978, however, renewed market instability has led to much higher prices. This study deals with the role of the world oil market structure and its implications for long-term equilibrium prices. Various market models are investigated to study the impact of large-scale cartelization and the probable long-term evolution in the event of a cartel breakdown. All results are referenced to the perfectly competitive solution. The theoretical structure of the various imperfect competition models follows the standard Nash-Cournot analysis of oligopolistic markets. The solutions are derived from dynamic optimization problems subject to the constraint of resource exhaustion. The empirical parameterization of the models is a simplified version of intricate realities. In spite of the simplified approach, important insights are gained on the nature of alternative world oil equilibria. The most-significant findings concern the stability of the relative effects of different imperfectly competitive models across parametric cases and the substantial monopoly gains attainable without large-scale cartelization.

  3. ASH and NASH.

    PubMed

    Scaglioni, F; Ciccia, S; Marino, M; Bedogni, G; Bellentani, S

    2011-01-01

    Non-alcoholic steatohepatitis (NASH) and alcoholic steatohepatitis (ASH) have a similar pathogenesis and histopathology but a different etiology and epidemiology. NASH and ASH are advanced stages of non-alcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD). NAFLD is characterized by excessive fat accumulation in the liver (steatosis), without any other evident causes of chronic liver diseases (viral, autoimmune, genetic, etc.), and with an alcohol consumption ≤20-30 g/day. On the contrary, AFLD is defined as the presence of steatosis and alcohol consumption >20-30 g/day. The most common phenotypic manifestations of primary NAFLD/NASH are overweight/obesity, visceral adiposity, type 2 diabetes, hypertriglyceridemia and hypertension. The prevalence of NAFLD in the general population in Western countries is estimated to be 25-30%. The prevalence and incidence of NASH and ASH are not known because of the impossibility of performing liver biopsy in the general population. Up to 90% of alcoholics have fatty liver, and 5-15% of these subjects will develop cirrhosis over 20 years. The risk of cirrhosis increases to 30-40% in those who continue to drink alcohol. About 10-35% of alcoholics exhibit changes on liver biopsy consistent with alcoholic hepatitis. Natural histories of NASH and ASH are not completely defined, even if patients with NASH have a reduced life expectancy due to liver-related death and cardiovascular diseases. The best treatment of AFLD/ASH is to stop drinking, and the most effective first-line therapeutic option for NAFLD/NASH is non-pharmacologic lifestyle interventions through a multidisciplinary approach including weight loss, dietary changes, physical exercise, and cognitive-behavior therapy. PMID:21734385

  4. Registration of 'Nash' Chickpea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The kabuli chickpea (Cicer arientinum L.) cultivar ‘Nash’ was released by the USDA-ARS in 2013 based on both its high yield and large seed size compared to the popular commercial chickpea cultivars ‘Sierra’ and ‘Sawyer’. Nash is an F5 derived line from the cross HB-19/CA9783142 and was evaluated in...

  5. The Nash equilibrium: a perspective.

    PubMed

    Holt, Charles A; Roth, Alvin E

    2004-03-23

    In 1950, John Nash contributed a remarkable one-page PNAS article that defined and characterized a notion of equilibrium for n- person games. This notion, now called the "Nash equilibrium," has been widely applied and adapted in economics and other behavioral sciences. Indeed, game theory, with the Nash equilibrium as its centerpiece, is becoming the most prominent unifying theory of social science. In this perspective, we summarize the historical context and subsequent impact of Nash's contribution. PMID:15024100

  6. A Tribute to Gary Nash

    ERIC Educational Resources Information Center

    Jason-Fives, Alli

    2009-01-01

    In this article, the author gives tribute to Gary Nash, a brilliant scholar, an award-winning professor, a prolific writer, a true humanitarian, and a revered historian. She honors him for his work with public school teachers. He has provided the educational support, encouragement, and motivation behind the importance of teaching history. Here,…

  7. Nash: genius with schizophrenia or vice versa?

    PubMed

    Funaki, Tevita

    2009-11-01

    Schizophrenia has many negative impacts on the wellbeing of individuals (sufferers). I will critically analyse Nash's experience with his illness of schizophrenia and his concept of wellness based on themes, his journey with schizophrenia and the support of this wife and friends. Ron Howard directed the movie, A Beautiful Mind based on Nash's biography about his mathematical genius and his struggle with schizophrenia. Nash only had one sister, Martha Nash who was born on November 16th, 1930. In terms of his mental health and wellness, Nash began to show signs of schizophrenia in 1958, on the threshold of his career. After 1970, by his choice, he never took antipsychotic medication again. In 1978, Nash was awarded the John von Neumann Theory Prize for his discovery of non-cooperative equilibria, now called Nash equilibria. As a result of Nash's illness, he adopted unhealthy practices that did not help him cope with schizophrenia. Recovery from mental illness has emphasised the importance of hope for the people experiencing mental illness. Nash's self-determinations enabled him to overcome the stigmatisation suffering due to schizophrenia. Nash experienced the five stages of coping with mental illness. The support of Nash's wife Alicia and the few close friends he had were paramount to his recovery and living with schizophrenia. Alicia had used cognitive coping strategies with her caring for Nash by having positive thinking in attempting to accept Nash's illness rather than denying that it existed and to understand the life experiences of a person with schizophrenia. Howard (2001) stated that it's about a 25% chance, that survivors of schizophrenia can regain clarity as Nash did within a certain time period. PMID:20443526

  8. Pre-Collegiate Teachers and Gary Nash

    ERIC Educational Resources Information Center

    Sesso, Gloria

    2009-01-01

    In this article, the author recalls the time she met Gary Nash at UCLA on July 13, 1992, when they began the work of creating the National Standards in History. Professor Nash was the leader in the development of the United States History Standards. In creating the Standards, they were to focus on Historical Thinking. They needed to organize the…

  9. NARSTO SOS99NASH WIND PROFILER DATA

    Atmospheric Science Data Center

    2014-04-25

    NARSTO SOS99NASH WIND PROFILER DATA Project Title:  NARSTO ... Platform:  Ground Station Instrument:  Wind Profiler Location:  Nashville, Tennessee Spatial ... Data Guide Documents:  SOS99Nash Wind Profiler Guide Related Data:  Southern Oxidants ...

  10. Model Checking Coalition Nash Equilibria in MAD Distributed Systems

    NASA Astrophysics Data System (ADS)

    Mari, Federico; Melatti, Igor; Salvo, Ivano; Tronci, Enrico; Alvisi, Lorenzo; Clement, Allen; Li, Harry

    We present two OBDD based model checking algorithms for the verification of Nash equilibria in finite state mechanisms modeling Multiple Administrative Domains (MAD) distributed systems with possibly colluding agents (coalitions) and with possibly faulty or malicious nodes (Byzantine agents). Given a finite state mechanism, a proposed protocol for each agent and the maximum sizes f for Byzantine agents and q for agents collusions, our model checkers return PASS if the proposed protocol is an ɛ-f-q-Nash equilibrium, i.e. no coalition of size up to q may have an interest greater than ɛ in deviating from the proposed protocol when up to f Byzantine agents are present, FAIL otherwise. We implemented our model checking algorithms within the NuSMV model checker: the first one explicitly checks equilibria for each coalition, while the second represents symbolically all coalitions. We present experimental results showing their effectiveness for moderate size mechanisms. For example, we can verify coalition Nash equilibria for mechanisms which corresponding normal form games would have more than 5 ×1021 entries. Moreover, we compare the two approaches, and the explicit algorithm turns out to outperform the symbolic one. To the best of our knowledge, no model checking algorithm for verification of Nash equilibria of mechanisms with coalitions has been previously published.

  11. Non-invasive Testing for NASH and NASH with Advanced Fibrosis: Are We There Yet?

    PubMed Central

    Arulanandan, Ahilan; Loomba, Rohit

    2015-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the most prevalent etiology of chronic liver disease in America. NAFLD can be broadly classified in two subtypes: nonalcoholic fatty liver (NAFL), which is generally considered a benign condition with negligible risk of progression to cirrhosis, and nonalcoholic steatohepatitis (NASH), which is generally considered to be progressive with substantial risk of progression to cirrhosis. Additionally, recent studies suggest the odds of liver mortality increases amongst NASH patients with advanced fibrosis (bridging fibrosis ± cirrhosis). Liver biopsy examination is the current gold standard to accurately discriminate between NAFL vs. NASH as well as diagnose advanced fibrosis. However, due to its invasive nature, risk of bleeding (and even rarely death), prohibitive cost, and sampling error, liver biopsies are imperfect for diagnosis and monitoring of NAFLD. As a result, noninvasive biomarkers that can accurately detect NASH and advanced fibrosis without biopsy are needed. This article will discuss the most novel noninvasive biomarkers in diagnosing NASH and advanced fibrosis. PMID:26500833

  12. On Learning Algorithms for Nash Equilibria

    NASA Astrophysics Data System (ADS)

    Daskalakis, Constantinos; Frongillo, Rafael; Papadimitriou, Christos H.; Pierrakos, George; Valiant, Gregory

    Can learning algorithms find a Nash equilibrium? This is a natural question for several reasons. Learning algorithms resemble the behavior of players in many naturally arising games, and thus results on the convergence or non-convergence properties of such dynamics may inform our understanding of the applicability of Nash equilibria as a plausible solution concept in some settings. A second reason for asking this question is in the hope of being able to prove an impossibility result, not dependent on complexity assumptions, for computing Nash equilibria via a restricted class of reasonable algorithms. In this work, we begin to answer this question by considering the dynamics of the standard multiplicative weights update learning algorithms (which are known to converge to a Nash equilibrium for zero-sum games). We revisit a 3×3 game defined by Shapley [10] in the 1950s in order to establish that fictitious play does not converge in general games. For this simple game, we show via a potential function argument that in a variety of settings the multiplicative updates algorithm impressively fails to find the unique Nash equilibrium, in that the cumulative distributions of players produced by learning dynamics actually drift away from the equilibrium.

  13. Local Nash Equilibrium in Social Networks

    PubMed Central

    Zhang, Yichao; Aziz-Alaoui, M. A.; Bertelle, Cyrille; Guan, Jihong

    2014-01-01

    Nash equilibrium is widely present in various social disputes. As of now, in structured static populations, such as social networks, regular, and random graphs, the discussions on Nash equilibrium are quite limited. In a relatively stable static gaming network, a rational individual has to comprehensively consider all his/her opponents' strategies before they adopt a unified strategy. In this scenario, a new strategy equilibrium emerges in the system. We define this equilibrium as a local Nash equilibrium. In this paper, we present an explicit definition of the local Nash equilibrium for the two-strategy games in structured populations. Based on the definition, we investigate the condition that a system reaches the evolutionary stable state when the individuals play the Prisoner's dilemma and snow-drift game. The local Nash equilibrium provides a way to judge whether a gaming structured population reaches the evolutionary stable state on one hand. On the other hand, it can be used to predict whether cooperators can survive in a system long before the system reaches its evolutionary stable state for the Prisoner's dilemma game. Our work therefore provides a theoretical framework for understanding the evolutionary stable state in the gaming populations with static structures. PMID:25169150

  14. Proteomic and lipidomic signatures of lipid metabolism in NASH-associated hepatocellular carcinoma.

    PubMed

    Muir, Kyle; Hazim, Antonious; He, Ying; Peyressatre, Marion; Kim, Do-Young; Song, Xiaoling; Beretta, Laura

    2013-08-01

    Nonalcoholic steatohepatitis (NASH) is a common preneoplastic condition of hepatocellular carcinoma (HCC). Mice with hepatocytic deletion of Pten develop NASH and HCC later in life. This model is highly valuable for studies aimed at identifying the molecular mechanism by which metabolic disorders contribute to tumor development. We applied proteomic and lipidomic profiling approaches to Pten-null NASH liver and tumors. Circulating fatty acid composition was also characterized in these mice. The relevance to human NASH and HCC was further validated. This integrative proteomic and lipidomic study from mouse to human and from liver to blood identified the following disease signatures: (i) an HCC signature: upregulated hepatic scd1/scd2, fads2, and acsl5:acsl1 ratio, elevated vaccenic and erucic acids, and reduced margaric and linoleic acids in both liver and plasma; (ii) a NASH signature that correlates with tumor burden: upregulated hepatic elovl6, elevated oleic, adrenic, and osbond acids, and reduced cervonic acid in liver and plasma; and (iii) a NASH signature: reduced hepatic and circulating lignoceric and eicosapentaenoic acids. Altogether, these results show the role of lipid-modifying enzymes converting saturated fatty acids (SFA) to monounsaturated fatty acids (MUFA) in HCC and the importance of an increased ratio of long chain n6-polyunsaturated fatty acids over n3-polyunsaturated fatty acids in NASH and HCC risk. They also highlight the relevance of the Pten-null model for studies related to NASH and HCC and show that circulating lipid metabolome provides a direct read of lipid changes in the liver. Most importantly, novel candidate targets for HCC diagnosis, therapy, risk assessment, and prevention were identified. PMID:23749645

  15. Quantum Nash Equilibria and Quantum Computing

    NASA Astrophysics Data System (ADS)

    Fellman, Philip Vos; Post, Jonathan Vos

    In 2004, At the Fifth International Conference on Complex Systems, we drew attention to some remarkable findings by researchers at the Santa Fe Institute (Sato, Farmer and Akiyama, 2001) about hitherto unsuspected complexity in the Nash Equilibrium. As we progressed from these findings about heteroclinic Hamiltonians and chaotic transients hidden within the learning patterns of the simple rock-paper-scissors game to some related findings on the theory of quantum computing, one of the arguments we put forward was just as in the late 1990's a number of new Nash equilibria were discovered in simple bi-matrix games (Shubik and Quint, 1996; Von Stengel, 1997, 2000; and McLennan and Park, 1999) we would begin to see new Nash equilibria discovered as the result of quantum computation. While actual quantum computers remain rather primitive (Toibman, 2004), and the theory of quantum computation seems to be advancing perhaps a bit more slowly than originally expected, there have, nonetheless, been a number of advances in computation and some more radical advances in an allied field, quantum game theory (Huberman and Hogg, 2004) which are quite significant. In the course of this paper we will review a few of these discoveries and illustrate some of the characteristics of these new "Quantum Nash Equilibria". The full text of this research can be found at http://necsi.org/events/iccs6/viewpaper.php?id-234

  16. Memories of Gary Nash over Five Decades

    ERIC Educational Resources Information Center

    Mellor, Ronald

    2009-01-01

    It is as a longtime client, softball teammate, colleague, traveling companion, and friend that the author writes this article to honor Gary Nash. He has known him in varied guises in five different decades, and on five continents, with Africa coming in 2009. In this article, the author recalls some of his memories of Gary over five decades.

  17. Gary Nash: Preeminent Scholar and Committed Educator

    ERIC Educational Resources Information Center

    Symcox, Linda

    2009-01-01

    The author has known Gary Nash as a friend since 1969, but she only began to work with him as a colleague in 1989, when he invited her to join the National Center for History in the Schools (NCHS) as it was just forming. During the seven years she spent as Assistant and then Associate Director of the NCHS, they shared the extraordinary experience…

  18. Gary Nash: Repairing a Necessary Connection

    ERIC Educational Resources Information Center

    Bender, Thomas

    2009-01-01

    In this essay, the author comments on the life and the contributions of author Gary Nash. Everyone is thanking him for his remarkable engagement with the schools, as a writer of outstanding textbooks and materials for teachers developed through his work as director of the Center for Teaching History in the Schools, and, of course, the National…

  19. On Nash equilibria in Eisert-Lewenstein-Wilkens game

    NASA Astrophysics Data System (ADS)

    Bolonek-Lasoń, Katarzyna; Kosiński, Piotr

    2015-12-01

    Landsburg method of classifying mixed Nash equilibria for maximally entangled Eisert-Lewenstein-Wilkens (ELW) game is analyzed with special emphasis on symmetries inherent to the problem. Nash equilibria for the original ELW game are determined.

  20. Uniqueness of Nash equilibrium in vaccination games.

    PubMed

    Bai, Fan

    2016-12-01

    One crucial condition for the uniqueness of Nash equilibrium set in vaccination games is that the attack ratio monotonically decreases as the vaccine coverage level increasing. We consider several deterministic vaccination models in homogeneous mixing population and in heterogeneous mixing population. Based on the final size relations obtained from the deterministic epidemic models, we prove that the attack ratios can be expressed in terms of the vaccine coverage levels, and also prove that the attack ratios are decreasing functions of vaccine coverage levels. Some thresholds are presented, which depend on the vaccine efficacy. It is proved that for vaccination games in homogeneous mixing population, there is a unique Nash equilibrium for each game. PMID:27465224

  1. Nash equilibrium and multi criterion aerodynamic optimization

    NASA Astrophysics Data System (ADS)

    Tang, Zhili; Zhang, Lianhe

    2016-06-01

    Game theory and its particular Nash Equilibrium (NE) are gaining importance in solving Multi Criterion Optimization (MCO) in engineering problems over the past decade. The solution of a MCO problem can be viewed as a NE under the concept of competitive games. This paper surveyed/proposed four efficient algorithms for calculating a NE of a MCO problem. Existence and equivalence of the solution are analyzed and proved in the paper based on fixed point theorem. Specific virtual symmetric Nash game is also presented to set up an optimization strategy for single objective optimization problems. Two numerical examples are presented to verify proposed algorithms. One is mathematical functions' optimization to illustrate detailed numerical procedures of algorithms, the other is aerodynamic drag reduction of civil transport wing fuselage configuration by using virtual game. The successful application validates efficiency of algorithms in solving complex aerodynamic optimization problem.

  2. Geometry of Cournot-Nash Equilibrium with Application to Commons and Anticommons

    ERIC Educational Resources Information Center

    D'Agata, Antonio

    2010-01-01

    The author develops a simple geometric analysis of Cournot-Nash equilibrium in the price-quantity space by exploiting the economic content of the first-order condition. The approach makes it clear that strategic interdependency in oligopoly originates from externalities among producers. This explains why cartels are unstable and casts oligopoly…

  3. Genetic and epigenetic mechanisms of NASH.

    PubMed

    Eslam, Mohammed; George, Jacob

    2016-05-01

    Along with the obesity epidemic, the prevalence of nonalcoholic fatty liver disease (NAFLD) has increased exponentially. The histological disease spectrum of NAFLD ranges from bland fatty liver (hepatic steatosis), to the concomitant presence of inflammation and ballooning which defines nonalcoholic steatohepatitis (NASH). The latter can progress in a subset to fibrosis, leading ultimately to cirrhosis and hepatocellular carcinoma. The past decade has seen tremendous advances in our understanding of the genetic and epigenetic bases of NAFLD, mainly through the application of high end technology platforms including genome-wide association studies (GWAS). These have helped to define common gene variants (minor allele frequency >5 %) that contribute to the NAFLD phenotype. Looking to the future, these discoveries are expected to lead to improved diagnostics, the personalization of medicine, and a better understanding of the pathophysiological underpinnings that drive the transition from NAFLD to steatohepatitis and fibrosis, leading to the identification of novel therapeutic targets. In this review, we summarize data on the current state of knowledge with regard to the genetic and epigenetic mechanisms for the development of NASH. PMID:26683320

  4. An Overview of NAFLD/NASH in Japan.

    PubMed

    Ryang Kim, Soo; Ih Kim, Ke

    2016-01-01

    Clinical identity of nonalcoholic steatohepatitis (NASH) has established it as a chronic liver disease since the 1990s in the USA and in the 21st century in Japan, although its significance is not well recognized in Japanese society. It is characterized as a chronic liver disease, differentiated from viral liver disease and alcoholic liver disease. Nonalcoholic fatty liver disease (NAFLD) comprises nonalcoholic fatty liver (NAFL) and NASH. NASH is considered to be the hepatic manifestation of a metabolic syndrome. It is understood that among individuals with NAFLD, NAFL is a benign condition, whereas NASH can progress to cirrhosis and ultimately to hepatocellular carcinoma. The precise mechanism of NASH is poorly understood, although insulin resistance, oxidative stress and multiple parallel hits theory have been reported. Computed tomography and ultrasonography are performed to detect NAFLD, but these are not sufficient to distinguish between NAFL and NASH. The distinct diagnosis of NAFL and NASH is currently made by liver biopsy, requiring hospitalization. Therefore, there is an urgent need to develop simple, non-invasive markers that can accurately distinguish between NASH and NAFL. In Japan, the number of NASH patients is estimated to be about 1 million. The treatment of NASH comprises changes in life style, including eating habits and exercise that will lead to weight loss, and drug intake, including vitamin E. Based on the global increase in obese people, NASH as a chronic liver disease will become the most important chronic liver disease in the 21st century, not only in Japan but also worldwide. PMID:27040340

  5. Evaluation of environmental genotoxicity by comet assay in Columba livia.

    PubMed

    González-Acevedo, Anahi; García-Salas, Juan A; Gosálvez, Jaime; Fernández, José Luis; Dávila-Rodríguez, Martha I; Cerda-Flores, Ricardo M; Méndez-López, Luis F; Cortés-Gutiérrez, Elva I

    2016-01-01

    The concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. The biomonitoring of environmental genotoxicity requires the selection of representative organisms as "sentinels," as well as the development of suitable and sensitive assays, such as those aimed at assessing DNA damage. The aim of this study was to evaluate DNA damage levels in erythrocytes from Columba livia living in the metropolitan area of Monterrey, Mexico, compared with control animals via comet assay, and to confirm the results via Micronuclei test (MN) and DNA breakage detection-fluorescence in situ hybridization (DBD-FISH). Our results showed a significant increase in DNA migration in animals from the area assayed compared with that observed in control animals sampled in non-contaminated areas. These results were confirmed by MN test and DBD-FISH. In conclusion, these observations confirm that the examination of erythrocytes from Columba livia via alkaline comet assay provides a sensitive and reliable end point for the detection of environmental genotoxicants. PMID:26608565

  6. Small Clique Detection and Approximate Nash Equilibria

    NASA Astrophysics Data System (ADS)

    Minder, Lorenz; Vilenchik, Dan

    Recently, Hazan and Krauthgamer showed [12] that if, for a fixed small ɛ, an ɛ-best ɛ-approximate Nash equilibrium can be found in polynomial time in two-player games, then it is also possible to find a planted clique in G n, 1/2 of size C logn, where C is a large fixed constant independent of ɛ. In this paper, we extend their result to show that if an ɛ-best ɛ-approximate equilibrium can be efficiently found for arbitrarily small ɛ> 0, then one can detect the presence of a planted clique of size (2 + δ) logn in G n, 1/2 in polynomial time for arbitrarily small δ> 0. Our result is optimal in the sense that graphs in G n, 1/2 have cliques of size (2 - o(1)) logn with high probability.

  7. Nash Equilibria in Theory of Reasoned Action

    NASA Astrophysics Data System (ADS)

    Almeida, Leando; Cruz, José; Ferreira, Helena; Pinto, Alberto Adrego

    2009-08-01

    Game theory and Decision Theory have been applied to many different areas such as Physics, Economics, Biology, etc. In its application to Psychology, we introduce, in the literature, a Game Theoretical Model of Planned Behavior or Reasoned Action by establishing an analogy between two specific theories. In this study we take in account that individual decision-making is an outcome of a process where group decisions can determine individual probabilistic behavior. Using Game Theory concepts, we describe how intentions can be transformed in behavior and according to the Nash Equilibrium, this process will correspond to the best individual decision/response taking in account the collective response. This analysis can be extended to several examples based in the Game Theoretical Model of Planned Behavior or Reasoned Action.

  8. The Nash Equilibrium Revisited: Chaos and Complexity Hidden in Simplicity

    NASA Astrophysics Data System (ADS)

    Fellman, Philip V.

    The Nash Equilibrium is a much discussed, deceptively complex, method for the analysis of non-cooperative games (McLennan and Berg, 2005). If one reads many of the commonly available definitions the description of the Nash Equilibrium is deceptively simple in appearance. Modern research has discovered a number of new and important complex properties of the Nash Equilibrium, some of which remain as contemporary conundrums of extraordinary difficulty and complexity (Quint and Shubik, 1997). Among the recently discovered features which the Nash Equilibrium exhibits under various conditions are heteroclinic Hamiltonian dynamics, a very complex asymptotic structure in the context of two-player bi-matrix games and a number of computationally complex or computationally intractable features in other settings (Sato, Akiyama and Farmer, 2002). This paper reviews those findings and then suggests how they may inform various market prediction strategies.

  9. Molecular cloning and sequencing analysis of the interferon receptor (IFNAR-1) from Columba livia

    PubMed Central

    Chang, Wei Shan

    2014-01-01

    Objective Partial sequence cloning of interferon receptor (IFNAR-1) of Columba livia. Material and methods In order to obtain a certain length (630 bp) of gene, a pair of primers was designed according to the conserved nucleotide sequence of Gallus (EU477527.1) and Taeniopygia guttata (XM_002189232.1) IFNAR-1 gene fragment that was published by GenBank. Special primers were designed by the Race method to amplify the 3'terminal cDNA. Results The Columba livia IFNAR-1 displayed 88.5%, 80.5% and 73.8% nucleotide identity to Falco peregrinus, Gallus and Taeniopygia guttata, respectively. Phylogenetic analysis of the IFNAR1 gene showed that the relationship of Columba livia, Falco peregrinus and chicken had high homology. Conclusions We successfully obtained a Columba livia IFNAR-1 gene partial sequence. Analysis of the genetic tree showed that the relationship of Columba livia and Falco peregrinus IFNAR-1 had high homology. This result can be used as reference for further research and practical application. PMID:26155117

  10. NASH (Nonalcoholic steatohepatitis): A case of multiorganelle failure.

    PubMed

    Caldwell, Stephen

    2014-10-01

    The clinical term 'multiorgan failure' lends itself, modified to 'multiorganelle failure', to the cascading events in cellular systems leading to hepatocyte injury, cell death, inflammation and fibrosis and ultimately to cirrhosis in NASH (non-alcoholic steatohepatitis). NASH is one of the most common forms of liver disease and constitutes the severe form of NAFLD (non-alcoholic fatty liver disease). The key features that distinguish potentially progressive NASH from relatively stable non-NASH fatty liver (NNFL, often referred to as simple steatosis) are cellular ballooning, inflammation and fibrosis. These findings, together with steatosis or accumulation of greater than normal hepatic lipid, usually constitute histological NASH seen on liver biopsy or in laboratory samples. Cellular ballooning is not specific to NASH but it is perhaps the most emblematic finding on histological samples. The ballooned hepatocyte has evidence of cytoskeletal injury (depletion and condensation as Mallory-Denk bodies), accumulation of partially oxidized small fat droplets, mitochondrial morphological changes presumably related to organelle dysfunction, dilated endoplasmic reticulum and autophagosomes - an attempt at cellular repair. Ballooning itself likely results from a combination of cytoskeletal injury resulting in loss of normal cell shape and from accumulation of injured and somewhat derelict small fat droplets and dilated endoplasmic reticulum. Cellular injury in NASH and especially cellular ballooning can be viewed as a process of 'multi-organelle failure' beginning with generation of super oxide and failure to contain the subsequent oxidative injury and by-products in an environment rich in lipid fuel. These events lead to activation of imunologic pathways. Dysfunction of the small fat droplet appears to be a central mechanism and the oxidative injury can be viewed as the process of rancidification - the chemical decomposition of oils, lipids and fats. PMID:26461413

  11. Nash equilibrium and evolutionary dynamics in semifinalists' dilemma

    NASA Astrophysics Data System (ADS)

    Baek, Seung Ki; Son, Seung-Woo; Jeong, Hyeong-Chai

    2015-04-01

    We consider a tournament among four equally strong semifinalists. The players have to decide how much stamina to use in the semifinals, provided that the rest is available in the final and the third-place playoff. We investigate optimal strategies for allocating stamina to the successive matches when players' prizes (payoffs) are given according to the tournament results. From the basic assumption that the probability to win a match follows a nondecreasing function of stamina difference, we present symmetric Nash equilibria for general payoff structures. We find three different phases of the Nash equilibria in the payoff space. First, when the champion wins a much bigger payoff than the others, any pure strategy can constitute a Nash equilibrium as long as all four players adopt it in common. Second, when the first two places are much more valuable than the other two, the only Nash equilibrium is such that everyone uses a pure strategy investing all stamina in the semifinal. Third, when the payoff for last place is much smaller than the others, a Nash equilibrium is formed when every player adopts a mixed strategy of using all or none of its stamina in the semifinals. In a limiting case that only last place pays the penalty, this mixed-strategy profile can be proved to be a unique symmetric Nash equilibrium, at least when the winning probability follows a Heaviside step function. Moreover, by using this Heaviside step function, we study the tournament by using evolutionary replicator dynamics to obtain analytic solutions, which reproduces the corresponding Nash equilibria on the population level and gives information on dynamic aspects.

  12. Nash equilibrium and evolutionary dynamics in semifinalists' dilemma.

    PubMed

    Baek, Seung Ki; Son, Seung-Woo; Jeong, Hyeong-Chai

    2015-04-01

    We consider a tournament among four equally strong semifinalists. The players have to decide how much stamina to use in the semifinals, provided that the rest is available in the final and the third-place playoff. We investigate optimal strategies for allocating stamina to the successive matches when players' prizes (payoffs) are given according to the tournament results. From the basic assumption that the probability to win a match follows a nondecreasing function of stamina difference, we present symmetric Nash equilibria for general payoff structures. We find three different phases of the Nash equilibria in the payoff space. First, when the champion wins a much bigger payoff than the others, any pure strategy can constitute a Nash equilibrium as long as all four players adopt it in common. Second, when the first two places are much more valuable than the other two, the only Nash equilibrium is such that everyone uses a pure strategy investing all stamina in the semifinal. Third, when the payoff for last place is much smaller than the others, a Nash equilibrium is formed when every player adopts a mixed strategy of using all or none of its stamina in the semifinals. In a limiting case that only last place pays the penalty, this mixed-strategy profile can be proved to be a unique symmetric Nash equilibrium, at least when the winning probability follows a Heaviside step function. Moreover, by using this Heaviside step function, we study the tournament by using evolutionary replicator dynamics to obtain analytic solutions, which reproduces the corresponding Nash equilibria on the population level and gives information on dynamic aspects. PMID:25974475

  13. Challenges and Management of Liver Cirrhosis: Practical Issues in the Therapy of Patients with Cirrhosis due to NAFLD and NASH.

    PubMed

    Traussnigg, Stefan; Kienbacher, Christian; Halilbasic, Emina; Rechling, Christian; Kazemi-Shirazi, Lili; Hofer, Harald; Munda, Petra; Trauner, Michael

    2015-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome and comprises a liver disease spectrum ranging from steatosis to nonalcoholic steatohepatitis (NASH) with risk of progression to liver cirrhosis and hepatocellular carcinoma (HCC). Associated metabolic conditions and comorbidities such as obesity, diabetes and cardiovascular diseases are common and require concerted management. Adiponutrin (PNPLA3) variants may help to identify NAFLD patients at higher risk for liver disease progression towards advanced fibrosis and HCC. The therapeutic options in NAFLD/NASH include lifestyle modification, pharmacological treatment, bariatric surgery for patients with morbid obesity and treatment of complications of liver cirrhosis and HCC, including liver transplantation. Insulin sensitizers and antioxidative treatment strategies with vitamin E are among the best-established pharmacological approaches, but both drugs have long-term safety issues and there is limited evidence in cirrhotic patients. Treatment of concomitant/underlying metabolic conditions with statins or metformin may also have beneficial effects on portal hypertension, complications of liver cirrhosis and HCC prevention. The bile acid receptor FXR may be a promising novel therapeutic target for the treatment of NAFLD/NASH, fibrosis and portal hypertension, but the prognostic implications of associated changes in low- and high-density lipoprotein cholesterol require further studies. Morbidly obese NASH patients can benefit from bariatric surgery which may reduce liver fibrosis but carries a risk of decompensation in patients with advanced liver cirrhosis. When carefully selected, patients with NASH cirrhosis undergoing liver transplantation have a good outcome. This review summarizes recent progress in the management of patients with liver cirrhosis due to NASH. PMID:26159280

  14. Nash equilibrium strategy in the deregulated power industry and comparing its lost welfare with Iran wholesale electricity market

    NASA Astrophysics Data System (ADS)

    Mousavi, Seyed Hosein; Nazemi, Ali; Hafezalkotob, Ashkan

    2016-07-01

    With the increasing use of different types of auctions in market designing, modeling of participants' behaviors to evaluate the market structure is one of the main discussions in the studies related to the deregulated power industries. In this article, we apply an approach of the optimal bidding behavior to the Iran wholesale electricity market as a restructured electric power industry and model how the participants of the market bid in the spot electricity market. The problem is formulated analytically using the Nash equilibrium concept composed of large numbers of players having discrete and very large strategy spaces. Then, we compute and draw supply curve of the competitive market in which all generators' proposed prices are equal to their marginal costs and supply curve of the real market in which the pricing mechanism is pay-as-bid. We finally calculate the lost welfare or inefficiency of the Nash equilibrium and the real market by comparing their supply curves with the competitive curve. We examine 3 cases on November 24 (2 cases) and July 24 (1 case), 2012. It is observed that in the Nash equilibrium on November 24 and demand of 23,487 MW, there are 212 allowed plants for the first case (plants are allowed to choose any quantity of generation except one of them that should be equal to maximum Power) and the economic efficiency or social welfare of Nash equilibrium is 2.77 times as much as the real market. In addition, there are 184 allowed plants for the second case (plants should offer their maximum power with different prices) and the efficiency or social welfare of Nash equilibrium is 3.6 times as much as the real market. On July 24 and demand of 42,421 MW, all 370 plants should generate maximum energy due to the high electricity demand that the economic efficiency or social welfare of the Nash equilibrium is about 2 times as much as the real market.

  15. John Nash, game theory, and the schizophrenic brain.

    PubMed

    Capps, Donald

    2011-03-01

    This article focuses on John Nash, recipient of the Nobel Prize in Economics in 1994, and subject of the Award winning 2001 film A Beautiful Mind, who was diagnosed with paranoid schizophrenia in 1958 at the age of 29. After presenting an account of the emergence, course, and eventual remission of his illness, the article argues for the relevance of his contribution to game theory, known as the Nash equilibrium, for which he received the Nobel Prize, to research studies of the schizophrenic brain and how it deviates from the normal brain. The case is made that the Nash equilibrium is descriptive of the normal brain, whereas the game theory formulated by John van Neumann, which Nash's theory challenges, is descriptive of the schizophrenic brain. The fact that Nash and his colleagues in mathematics did not make the association between his contributions to mathematics and his mental breakdown and that his later recovery exemplified the validity of this contribution are noted and discussed. Religious themes in his delusional system, including his view of himself as a secret messianic figure and the biblical Esau, are interpreted in light of these competing game theories and the dysfunctions of the schizophrenic brain. His recognition that his return to normalcy came at the price of his sense of being in relation to the cosmos is also noted. PMID:19862621

  16. The generalized Nash model for river flow routing

    NASA Astrophysics Data System (ADS)

    Yan, Baowei; Guo, Shenglian; Liang, Ji; Sun, Huaiwei

    2015-11-01

    The widely used instantaneous unit hydrograph (IUH) based on the Nash cascade reservoir model was obtained under a zero initial condition, or equivalently an empty reservoir assumption. In this study, a more general case with a non-zero initial condition is considered in the derivation of the classical Nash model. A generalized Nash model (GNM) has been deduced using the Laplace transform and the principle of mathematical induction. For river flow routing, the GNM physically interprets the formation of downstream outflow, i.e. the summation of the recession flow of the initial channel storage and the response to upstream inflow. The GNM, written in a state-space representation, is able to update the state of the river system in time, and hence can be applied in real-time forecasting. Two separate case studies have been used for illustration. It is indicated that the proposed updating procedure results in improved river flow forecasts when compared with the traditional IUH method.

  17. Acute, fatal Sarcocystis calchasi-associated hepatitis in Roller pigeons (Columbia livia f. dom.) at Philadelphia Zoo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four Roller pigeons (Columba livia f. dom.) at the Philadelphia Zoo died suddenly. Necropsy examination revealed macroscopic hepatitis. Microscopically, the predominant lesions were in liver, characterized with necrosis and mixed cell inflammatory response. Sarcocystis calchasi-like schizonts and fr...

  18. Stress-induced core temperature changes in pigeons (Columba livia).

    PubMed

    Bittencourt, Myla de Aguiar; Melleu, Fernando Falkenburger; Marino-Neto, José

    2015-02-01

    Changes in body temperature are significant physiological consequences of stressful stimuli in mammals and birds. Pigeons (Columba livia) prosper in (potentially) stressful urban environments and are common subjects in neurobehavioral studies; however, the thermal responses to stress stimuli by pigeons are poorly known. Here, we describe acute changes in the telemetrically recorded celomatic (core) temperature (Tc) in pigeons given a variety of potentially stressful stimuli, including transfer to a novel cage (ExC) leading to visual isolation from conspecifics, the presence of the experimenter (ExpR), gentle handling (H), sham intracelomatic injections (SI), and the induction of the tonic immobility (TI) response. Transfer to the ExC cage provoked short-lived hyperthermia (10-20 min) followed by a long-lasting and substantial decrease in Tc, which returned to baseline levels 2 h after the start of the test. After a 2-hour stay in the ExC, the other potentially stressful stimuli evoked only weak, marginally significant hyperthermic (ExpR, IT) or hypothermic (SI) responses. Stimuli delivered 26 h after transfer to the ExC induced definite and intense increases in Tc (ExpR, H) or hypothermic responses (SI). These Tc changes appear to be unrelated to modifications in general activity (as measured via telemetrically recorded actimetric data). Repeated testing failed to affect the hypothermic responses to the transference to the ExC, even after nine trials and at 1- or 8-day intervals, suggesting that the social (visual) isolation from conspecifics may be a strong and poorly controllable stimulus in this species. The present data indicated that stress-induced changes in Tc may be a consistent and reliable physiological parameter of stress but that they may also show stressor type-, direction- and species-specific attributes. PMID:25479572

  19. Innate Immunity and Inflammation in NAFLD/NASH.

    PubMed

    Arrese, Marco; Cabrera, Daniel; Kalergis, Alexis M; Feldstein, Ariel E

    2016-05-01

    Inflammation and hepatocyte injury and death are the hallmarks of nonalcoholic steatohepatitis (NASH), the progressive form of nonalcoholic fatty liver disease (NAFLD), which is a currently burgeoning public health problem. Innate immune activation is a key factor in triggering and amplifying hepatic inflammation in NAFLD/NASH. Thus, identification of the underlying mechanisms by which immune cells in the liver recognize cell damage signals or the presence of pathogens or pathogen-derived factors that activate them is relevant from a therapeutic perspective. In this review, we present new insights into the factors promoting the inflammatory response in NASH including sterile cell death processes resulting from lipotoxicity in hepatocytes as well as into the altered gut-liver axis function, which involves translocation of bacterial products into portal circulation as a result of gut leakiness. We further delineate the key immune cell types involved and how they recognize both damage-associated molecular patterns or pathogen-associated molecular patterns through binding of surface-expressed pattern recognition receptors, which initiate signaling cascades leading to injury amplification. The relevance of modulating these inflammatory signaling pathways as potential novel therapeutic strategies for the treatment of NASH is summarized. PMID:26841783

  20. 26. Photocopy of original photograph in collection of John Nash, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Photocopy of original photograph in collection of John Nash, Cleveland Water Department showing nine foot tunnel under Lake Erie for water supply. location is a Crib #1. photo undated. - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  1. Dynamic elastic Cournot-Nash principle with memory term

    NASA Astrophysics Data System (ADS)

    Barbagallo, Annamaria

    2013-10-01

    In the paper we consider the dynamic elastic oligopolistic market equilibrium problem in presence of production excesses and show the equivalence between the generalized Cournot-Nash principle and a quasi-variational inequality. Moreover, we present existence and regularity results for equilibrium solutions. Finally, we introduce a long term memory in order to take into account the delay effects in the noncooperative market.

  2. Critical Realism and Statistical Methods--A Response to Nash

    ERIC Educational Resources Information Center

    Scott, David

    2007-01-01

    This article offers a defence of critical realism in the face of objections Nash (2005) makes to it in a recent edition of this journal. It is argued that critical and scientific realisms are closely related and that both are opposed to statistical positivism. However, the suggestion is made that scientific realism retains (from statistical…

  3. 13. Photocopy of original photograph in collection of John Nash, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Photocopy of original photograph in collection of John Nash, Cleveland Water Department, showing Allis Chambers triple-expansion steam engine at the Division Avenue Plant. Photo ca. 1900-1920. Engine now demolished. - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  4. Surviving History: Gary Nash and the National Standards

    ERIC Educational Resources Information Center

    Bingham, Marjorie

    2009-01-01

    In this article, the author recalls the first time she met Gary Nash. He came to speak at a Bradley Commission meeting and she was rather surprised to see him appear and to find out that he, along with Charlotte Crabtree, was involved in a National Center for History. She gives three reasons for her surprise which she thinks may tell aspects of…

  5. Current efforts and trends in the treatment of NASH.

    PubMed

    Ratziu, Vlad; Goodman, Zachary; Sanyal, Arun

    2015-04-01

    Of all the aspects of non-alcoholic fatty liver disease (NAFLD), the slowest advances have occurred in the therapeutic field. Thirty-five years after its formal description and after 15 years of intense scrutiny from researchers worldwide, there is still no approved drug for the treatment of non-alcoholic steatohepatits (NASH). In the meantime, progress in the understanding of pathophysiology, diagnosis - both invasive and non-invasive, epidemiology and even natural history have been substantial or, at times, spectacular. In contrast, hepatitis C virus (HCV) therapy underwent constant improvement and even before the great acceleration of the past few years, patients were already being offered approved therapies that were increasingly more efficient. What then explains such a slow pace of therapeutic advances in NASH, and will this change in the near future? Here we will review commonly-held myths that have diverted attention from therapy of NASH, obstacles that have slowed down industrial development of drugs for this indication, and recent achievements that will create better conditions for drug development programs. We will also briefly review current knowledge of non-pharmacological and pharmacological management in this early era of NASH therapies. PMID:25920092

  6. Imaging Mass Spectrometry Reveals a Decrease of Cardiolipin in the Kidney of NASH Model Mice.

    PubMed

    Hayasaka, Takahiro; Fuda, Hirotoshi; Hui, Shu-Ping; Chiba, Hitoshi

    2016-01-01

    Non-alcoholic steatohepatitis (NASH) can be complicated with chronic kidney disease (CKD). In this study, changes in the distribution of biomolecules in the kidney were studied in NASH model mice with the use of imaging mass spectrometry (IMS). The mass spectra and ion images of IMS showed that the signals of cardiolipin (CL) species were decreased in the kidney cortex of the NASH mice. The decrease of CL might therefore suggest the kidney involvement of NASH. PMID:27063723

  7. Role of MicroRNAs in NAFLD/NASH.

    PubMed

    Szabo, Gyongyi; Csak, Timea

    2016-05-01

    MicroRNAs (miRNAs) are highly conserved, small, 18-25 nucleotide, non-coding RNAs that regulate gene expression at the post-transcriptional level. Each miRNA can regulate hundreds of target genes, and vice versa each target gene can be regulated by numerous miRNAs, suggesting a very complex network and explaining how miRNAs play pivotal roles in fine-tuning essentially all biological processes in all cell types in the liver. Here, we summarize the current knowledge on the role of miRNAs in the pathogenesis and diagnosis of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) with an outlook to the broader aspects of metabolic syndrome. Furthermore, we discuss the role of miRNAs as potential biomarkers and therapeutic targets in NAFLD/NASH. PMID:26769057

  8. Nash Equilibria in Noncooperative Predator-Prey Games

    SciTech Connect

    Ramos, Angel Manuel Roubicek, Tomas

    2007-09-15

    A noncooperative game governed by a distributed-parameter predator-prey system is considered, assuming that two players control initial conditions for predator and prey, respectively. Existence of a Nash equilibrium is shown under the condition that the desired population profiles and the environmental carrying capacity for the prey are sufficiently small. A conceptual approximation algorithm is proposed and analyzed. Finally, numerical simulations are performed, too.

  9. Investigation of land use effects on Nash model parameters

    NASA Astrophysics Data System (ADS)

    Niazi, Faegheh; Fakheri Fard, Ahmad; Nourani, Vahid; Goodrich, David; Gupta, Hoshin

    2015-04-01

    Flood forecasting is of great importance in hydrologic planning, hydraulic structure design, water resources management and sustainable designs like flood control and management. Nash's instantaneous unit hydrograph is frequently used for simulating hydrological response in natural watersheds. Urban hydrology is gaining more attention due to population increases and associated construction escalation. Rapid development of urban areas affects the hydrologic processes of watersheds by decreasing soil permeability, flood base flow, lag time and increase in flood volume, peak runoff rates and flood frequency. In this study the influence of urbanization on the significant parameters of the Nash model have been investigated. These parameters were calculated using three popular methods (i.e. moment, root mean square error and random sampling data generation), in a small watershed consisting of one natural sub-watershed which drains into a residentially developed sub-watershed in the city of Sierra Vista, Arizona. The results indicated that for all three methods, the lag time, which is product of Nash parameters "K" and "n", in the natural sub-watershed is greater than the developed one. This logically implies more storage and/or attenuation in the natural sub-watershed. The median K and n parameters derived from the three methods using calibration events were tested via a set of verification events. The results indicated that all the three method have acceptable accuracy in hydrograph simulation. The CDF curves and histograms of the parameters clearly show the difference of the Nash parameter values between the natural and developed sub-watersheds. Some specific upper and lower percentile values of the median of the generated parameters (i.e. 10, 20 and 30 %) were analyzed to future investigates the derived parameters. The model was sensitive to variations in the value of the uncertain K and n parameter. Changes in n are smaller than K in both sub-watersheds indicating

  10. A generalization of Nash's theorem with higher-order functionals

    PubMed Central

    Hedges, Julian

    2013-01-01

    The recent theory of sequential games and selection functions by Escardó & Oliva is extended to games in which players move simultaneously. The Nash existence theorem for mixed-strategy equilibria of finite games is generalized to games defined by selection functions. A normal form construction is given, which generalizes the game-theoretic normal form, and its soundness is proved. Minimax strategies also generalize to the new class of games, and are computed by the Berardi–Bezem–Coquand functional, studied in proof theory as an interpretation of the axiom of countable choice. PMID:23750111

  11. Bayesian Nash equilibria using extended Werner-like states

    NASA Astrophysics Data System (ADS)

    Alid-Vaccarezza, M.; Soto, M. E.

    2016-07-01

    We study quantum strategies in games of incomplete information using a formalism of game theory based on multi-sector probability matrix. We analyze an extension of the well-known game of Battle of Sexes using an extended Werner-like state focusing in how its mixedness and entanglement affect the Bayesian Nash payoffs of the player. It is shown that entanglement is needed to outperform classical payoffs but not all entangled states are useful due to the presence of mixedness. A threshold for the mixedness parameter and the minimum entanglement value were found.

  12. CEACAM1 loss links inflammation to Insulin Resistance in obesity and Non-alcoholic Steatohepatitis (NASH)

    PubMed Central

    Najjar, Sonia M.; Russo, Lucia

    2014-01-01

    Mounting epidemiological evidence points to an association between metabolic syndrome and non-alcoholic steatohepatitis (NASH), an increasingly recognized new epidemic. NASH pathologies include hepatocellular ballooning, lobular inflammation, hepatocellular injury, apoptosis and hepatic fibrosis. We will review the relationship between insulin resistance and inflammation in visceral obesity and NASH in an attempt to shed more light on the pathogenesis of these major metabolic diseases. Moreover, we will identify loss of the Carcinoembryonic antigen-related cell adhesion molecule 1 as a unifying mechanism linking the immunological and metabolic abnormalities in NASH. PMID:24258517

  13. Two Monthly Continuous Dynamic Model Based on Nash Bargaining Theory for Conflict Resolution in Reservoir System.

    PubMed

    Homayounfar, Mehran; Zomorodian, Mehdi; Martinez, Christopher J; Lai, Sai Hin

    2015-01-01

    So far many optimization models based on Nash Bargaining Theory associated with reservoir operation have been developed. Most of them have aimed to provide practical and efficient solutions for water allocation in order to alleviate conflicts among water users. These models can be discussed from two viewpoints: (i) having a discrete nature; and (ii) working on an annual basis. Although discrete dynamic game models provide appropriate reservoir operator policies, their discretization of variables increases the run time and causes dimensionality problems. In this study, two monthly based non-discrete optimization models based on the Nash Bargaining Solution are developed for a reservoir system. In the first model, based on constrained state formulation, the first and second moments (mean and variance) of the state variable (water level in the reservoir) is calculated. Using moment equations as the constraint, the long-term utility of the reservoir manager and water users are optimized. The second model is a dynamic approach structured based on continuous state Markov decision models. The corresponding solution based on the collocation method is structured for a reservoir system. In this model, the reward function is defined based on the Nash Bargaining Solution. Indeed, it is used to yield equilibrium in every proper sub-game, thereby satisfying the Markov perfect equilibrium. Both approaches are applicable for water allocation in arid and semi-arid regions. A case study was carried out at the Zayandeh-Rud river basin located in central Iran to identify the effectiveness of the presented methods. The results are compared with the results of an annual form of dynamic game, a classical stochastic dynamic programming model (e.g. Bayesian Stochastic Dynamic Programming model, BSDP), and a discrete stochastic dynamic game model (PSDNG). By comparing the results of alternative methods, it is shown that both models are capable of tackling conflict issues in water allocation

  14. Two Monthly Continuous Dynamic Model Based on Nash Bargaining Theory for Conflict Resolution in Reservoir System

    PubMed Central

    Homayounfar, Mehran; Zomorodian, Mehdi; Martinez, Christopher J.; Lai, Sai Hin

    2015-01-01

    So far many optimization models based on Nash Bargaining Theory associated with reservoir operation have been developed. Most of them have aimed to provide practical and efficient solutions for water allocation in order to alleviate conflicts among water users. These models can be discussed from two viewpoints: (i) having a discrete nature; and (ii) working on an annual basis. Although discrete dynamic game models provide appropriate reservoir operator policies, their discretization of variables increases the run time and causes dimensionality problems. In this study, two monthly based non-discrete optimization models based on the Nash Bargaining Solution are developed for a reservoir system. In the first model, based on constrained state formulation, the first and second moments (mean and variance) of the state variable (water level in the reservoir) is calculated. Using moment equations as the constraint, the long-term utility of the reservoir manager and water users are optimized. The second model is a dynamic approach structured based on continuous state Markov decision models. The corresponding solution based on the collocation method is structured for a reservoir system. In this model, the reward function is defined based on the Nash Bargaining Solution. Indeed, it is used to yield equilibrium in every proper sub-game, thereby satisfying the Markov perfect equilibrium. Both approaches are applicable for water allocation in arid and semi-arid regions. A case study was carried out at the Zayandeh-Rud river basin located in central Iran to identify the effectiveness of the presented methods. The results are compared with the results of an annual form of dynamic game, a classical stochastic dynamic programming model (e.g. Bayesian Stochastic Dynamic Programming model, BSDP), and a discrete stochastic dynamic game model (PSDNG). By comparing the results of alternative methods, it is shown that both models are capable of tackling conflict issues in water allocation

  15. Multi Objective Aerodynamic Optimization Using Parallel Nash Evolutionary/deterministic Hybrid Algorithms

    NASA Astrophysics Data System (ADS)

    Tang, Zhili

    2016-06-01

    This paper solved aerodynamic drag reduction of transport wing fuselage configuration in transonic regime by using a parallel Nash evolutionary/deterministic hybrid optimization algorithm. Two sets of parameters are used, namely globally and locally. It is shown that optimizing separately local and global parameters by using Nash algorithms is far more efficient than considering these variables as a whole.

  16. 75 FR 41518 - Match-E-Be-Nash-She-Wish (Gun Lake) Tribe Liquor Control Ordinance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... Bureau of Indian Affairs Match-E-Be-Nash-She-Wish (Gun Lake) Tribe Liquor Control Ordinance AGENCY... certification of the Match-E-Be-Nash-She-Wish Band of Pottawatomi Indians (Gun Lake) Liquor Control Ordinance... purpose of regulating liquor transactions in Indian Country. The Tribal Council of the Gun Lake...

  17. Two-population replicator dynamics and number of Nash equilibria in matrix games

    NASA Astrophysics Data System (ADS)

    Galla, T.

    2007-04-01

    We study the connection between the evolutionary replicator dynamics and the number of Nash equilibria in large random bi-matrix games. Using techniques of disordered systems theory we compute the statistical properties of both, the fixed points of the dynamics and the Nash equilibria. Except for the special case of zero-sum games, one finds a transition as a function of the so-called co-operation pressure between a phase in which there is a unique stable fixed point of the dynamics coinciding with a unique Nash equilibrium, and an unstable phase in which there are exponentially many Nash equilibria with statistical properties different from the stationary state of the replicator equations. Our analytical results are confirmed by numerical simulations of the replicator dynamics, and by explicit enumeration of Nash equilibria.

  18. [Current trends of NASH/NAFLD in Asia-Pacific region].

    PubMed

    Ishii, Hiromasa

    2006-06-01

    In Japan, much attention has been paid to NASH and NAFLD for the past several years and the prevalence of this disease entity has been estimated, and NASH is thought to be present in 10% of those who have fatty liver diseases. Other points out the prevalence of NASH in Japan as 6 to 8 hundred thousand patients. The last two or three decades have seen the evolution of Western-style life of near complete inactivity, energy-dense food choices and liberal fiscal resources to obtain them and other means to avoid physical activity. Moreover, what is increasingly apparent is that NASH and NAFLD is not a Western disease and many population groups in the Asia-Pacific region are particularly prone to type 2 diabetes. Thus, it is not surprising that NASH has increasingly been diagnosed in several regions in Asia including Indonesia, Malaysia, Philippines, Thailand and India. PMID:16768103

  19. Navigable networks as Nash equilibria of navigation games

    NASA Astrophysics Data System (ADS)

    Gulyás, András; Bíró, József J.; Kőrösi, Attila; Rétvári, Gábor; Krioukov, Dmitri

    2015-07-01

    Common sense suggests that networks are not random mazes of purposeless connections, but that these connections are organized so that networks can perform their functions well. One function common to many networks is targeted transport or navigation. Here, using game theory, we show that minimalistic networks designed to maximize the navigation efficiency at minimal cost share basic structural properties with real networks. These idealistic networks are Nash equilibria of a network construction game whose purpose is to find an optimal trade-off between the network cost and navigability. We show that these skeletons are present in the Internet, metabolic, English word, US airport, Hungarian road networks, and in a structural network of the human brain. The knowledge of these skeletons allows one to identify the minimal number of edges, by altering which one can efficiently improve or paralyse navigation in the network.

  20. Navigable networks as Nash equilibria of navigation games.

    PubMed

    Gulyás, András; Bíró, József J; Kőrösi, Attila; Rétvári, Gábor; Krioukov, Dmitri

    2015-01-01

    Common sense suggests that networks are not random mazes of purposeless connections, but that these connections are organized so that networks can perform their functions well. One function common to many networks is targeted transport or navigation. Here, using game theory, we show that minimalistic networks designed to maximize the navigation efficiency at minimal cost share basic structural properties with real networks. These idealistic networks are Nash equilibria of a network construction game whose purpose is to find an optimal trade-off between the network cost and navigability. We show that these skeletons are present in the Internet, metabolic, English word, US airport, Hungarian road networks, and in a structural network of the human brain. The knowledge of these skeletons allows one to identify the minimal number of edges, by altering which one can efficiently improve or paralyse navigation in the network. PMID:26138277

  1. Navigable networks as Nash equilibria of navigation games

    PubMed Central

    Gulyás, András; Bíró, József J.; Kőrösi, Attila; Rétvári, Gábor; Krioukov, Dmitri

    2015-01-01

    Common sense suggests that networks are not random mazes of purposeless connections, but that these connections are organized so that networks can perform their functions well. One function common to many networks is targeted transport or navigation. Here, using game theory, we show that minimalistic networks designed to maximize the navigation efficiency at minimal cost share basic structural properties with real networks. These idealistic networks are Nash equilibria of a network construction game whose purpose is to find an optimal trade-off between the network cost and navigability. We show that these skeletons are present in the Internet, metabolic, English word, US airport, Hungarian road networks, and in a structural network of the human brain. The knowledge of these skeletons allows one to identify the minimal number of edges, by altering which one can efficiently improve or paralyse navigation in the network. PMID:26138277

  2. EFFECTS OF N-ACETYLCYSTEINE ON NON-ALCOHOLIC STEATOHEPATITIS (NASH) IN RATS FED VIA TOTAL ENTERAL NUTRITION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A "two-hit" model for NASH exists in which development of steatosis constitutes the "first hit" and sensitizes the liver to potential "second hits", resulting in NASH. Oxidative stress is possibly a central mechanism of hepatocellular injury in NASH and is a candidate for the "second hit" since it c...

  3. [Which animal models of nonalcoholic steatohepatitis-hepatocellular carcinoma (NASH-HCC) have more practical value in experimental investigations?].

    PubMed

    Duan, N N; Wu, J

    2016-03-20

    In the past, we used to think that hepatocellular carcinoma (HCC) only occurred when nonalcoholic fatty liver disease (NAFLD) progressed to liver cirrhosis. However, recent clinical studies have shown that HCC may occur during the stage of nonalcoholic steatohepatitis (NASH). The prevalence of NAFLD and the increasing incidence of NASH-associated HCC require the elucidation of the pathogenesis of NASH-HCC and the assessment of the efficacy of novel therapies as early as possible, while these evaluations need reliable animal models. This article reviews the characteristics of NASH-HCC models with a practical value to uncover the mysteries of NASH-HCC. PMID:27095770

  4. Antioxidant potential of the root of Vetiveria zizanioides (L.) Nash.

    PubMed

    Luqman, Suaib; Kumar, Ritesh; Kaushik, Shubhangi; Srivastava, Suchita; Darokar, Mahendra P; Khanuja, Suman P S

    2009-02-01

    Vetiveria zizanioides, an aromatic plant commonly known as vetiver has been used for various ailments. The essential oil of vetiver root has been shown to possess antioxidant activity. However, antioxidant potential of spent root extract has not been reported. Hence, in the present study, ferric reducing, free radical scavenging and antioxidant activity of two genotypes namely KS1 and gulabi of V. zizanioides L. Nash root were investigated using in vitro assays - the ferric reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH), total phenolic content (TPC), total antioxidant capacity (TAC) and reducing power (RP). KS1 genotype showed higher FRAP values, DPPH inhibition, TPC and RP potential compared to gulabi and the antioxidant activity increased with the concentration of the extract (10-1000 microg/mL). A significant protective effect of cv KS1 (100 microg/mL) extract was also observed in reduced glutathione (GSH) and malondialdehyde (MDA) concentrations of erythrocytes subjected to oxidative stress by tert-butyl hydroperoxide (t-BHP) and hydrogen peroxide (H202). The cv KS1 showed better antioxidant activity, compared to cv gulabi indicating the possibility of exploring the presence of different phytoconstituents in the two varieties. PMID:19374265

  5. Role of NLRP3 Inflammasome in the Progression of NAFLD to NASH

    PubMed Central

    Wan, Xingyong; Xu, Chengfu; Yu, Chaohui; Li, Youming

    2016-01-01

    Nonalcoholic fatty liver disease (NAFLD) has been recognized as a major public health problem worldwide. Nonalcoholic steatohepatitis (NASH) is an advanced form of NAFLD that may progress to cirrhosis and hepatocellular carcinoma. The pathogenesis of disease progression from NAFLD to NASH has not been fully understood. Immunological mechanisms that have been increasingly recognized in the disease progression include defects in innate immunity, adaptive immunity, Toll-like receptor (TLR) signaling, and gut-liver axis. The NLRP3 inflammasome is an intracellular multiprotein complex involved in the production of mature interleukin 1-beta (IL-1β) and induces metabolic inflammation. NLRP3 inflammasome has been recently demonstrated to play a crucial role in the progression of NASH. This review highlights the recent findings linking NLRP3 inflammasome to the progression of NASH. PMID:27446858

  6. Mycoplasma columbinum Isolated From a Racing Pigeon ( Columba livia ) With Arthritis.

    PubMed

    Hellebuyck, Tom; Garmyn, An; De Cooman, Lien; Boyen, Filip; Pasmans, Frank; Martel, An

    2014-09-01

    A juvenile racing pigeon ( Columba livia ) was presented with drooping of the wing and inability to fly. On physical examination, the right shoulder joint was swollen. The pigeon was euthanatized and submitted for necropsy. An excessive amount of fibrin was present in the canalis triosseus with severe arthritis of the affected shoulder joint. A pure growth of Mycoplasma-like colonies was obtained on microbiological culture of the shoulder joint. A 16S ribosomal RNA gene-specific polymerase chain reaction assay was performed on the isolate and revealed 100% similarity with Mycoplasma columbinum . Although infectious arthritis in homing pigeons is primarily associated with paratyphoid and Streptococcus gallolyticus infection, clinical practitioners should consider the potential role of Mycoplasma columbinum in arthritis in pigeons. PMID:25843324

  7. Invasion of Flukes of the Echinostomatidae Family in Racing Pigeon ( Columba livia var. domestica) Lofts.

    PubMed

    Ledwoń, Aleksandra; Dolka, Beata; Piasecki, Tomasz; Dolka, Izabella; Szeleszczuk, Piotr

    2016-06-01

    Over 4 years, only two known cases of fluke invasions were diagnosed in racing pigeons ( Columba livia ) originating from different regions of Poland. In both cases, the invasion was characterized by a very high mortality (approximately 70%), and the source of the infestation was snails of the Lymnaeidae family eaten by pigeons. Fluke invasions in pigeons are extremely rare and to date have not been described in Poland. Therefore, the occurrence of the symptoms of hemorrhagic diarrhea and sudden deaths of either adult pigeons or nestlings were suspected to be associated with poisoning. Autopsy revealed an invasion of flukes causing hemorrhagic enteritis. Renal failure and spleen atrophy were also found in the birds. Using molecular biology techniques, infestation with the fluke Echinostoma revolutum was determined in the second case. PMID:27309299

  8. Helminth-bacteria interaction in the gut of domestic pigeon Columba livia domestica.

    PubMed

    Biswal, Debraj; Nandi, Anadi Prasad; Chatterjee, Soumendranath

    2016-03-01

    The present paper is an attempt to study the interaction between the helminth parasite and bacteria residing in the gut of domestic pigeon, Columba livia domestica. Biochemical and molecular characterization of the gut bacterial isolate were done and the isolate was identified as Staphylococcus sp. DB1 (JX442510). The interaction of Staphylococcus sp. with Cotugnia cuneata, an intestinal helminth parasite of domestic pigeon was studied on the basis of the difference between 'mean worm burden' of antibiotic treated infected pigeons and infected pigeons without any antibiotic treatment. The ANOVA and Tukey tests of the data obtained showed that antibiotic treatment reduced the mean worm burden significantly. The biochemical properties of Staphylococcus sp. DB1 (JX442510) also showed a mutualistic relationship with the physiology of C. cuneata. PMID:27065609

  9. Age-correlation of blood values in the rock pigeon (Columba livia).

    PubMed

    Prinzinger, Roland; Misovic, Andrea

    2010-07-01

    Hematological adaptations to age (1-17 years) and about variability per se for free-living rock pigeons Columba livia are presented. Increasing age is correlated with decreasing values of hematocrit and hemoglobin. A marked reduction of lactate dehydrogenase (EC 1.1.1.27) activity in the first 2-3 years may be caused by a training-based increase of the relative portion of the aerobically working red breast muscles (responsible for endurance) at the expense of the proportion of anaerobically working white breast muscles. The age-correlated increase in glucose could indicate a decreasing tolerance for carbohydrates. Optimal flight performance is achieved by the doves at an age of about 2-3 years; the high performance is retained until an age range of 7-9 years. PMID:20184962

  10. A Bidding Methodology by Nash Equilibrium for Finite Generators Participating in Imperfect Electricity Markets

    NASA Astrophysics Data System (ADS)

    Satyaramesh, P. V.

    2014-01-01

    This paper presents an application of finite n-person non-cooperative game theory for analyzing bidding strategies of generators in a deregulated energy marketplace with Pool Bilateral contracts so as to maximize their net profits. A new methodology to build bidding methodology for generators participating in oligopoly electricity market has been proposed in this paper. It is assumed that each generator bids a supply function. This methodology finds out the coefficients in the supply function of generators in order to maximize benefits in an environment of competing rival bidders. A natural choice for developing strategies is Nash Equilibrium (NE) model incorporating mixed strategies, for solving the bidding problem of electrical market. Associated optimal profits are evaluated for a combination of set of pure strategies of bidding of generators, and payoff matrix has been constructed. The optimal payoff is calculated by using NE. An attempt has also been made to minimize the gap between the optimal payoff and the payoff obtained by a possible mixed strategies combination. The algorithm is coded in MATLAB. A numerical example is used to illustrate the essential features of the approach and the results are proved to be the optimal values.

  11. Hepatic cholesterol crystals and crown-like structures distinguish NASH from simple steatosis.

    PubMed

    Ioannou, George N; Haigh, W Geoffrey; Thorning, David; Savard, Christopher

    2013-05-01

    We sought to determine whether hepatic cholesterol crystals are present in patients or mice with nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NASH), and whether their presence or distribution correlates with the presence of NASH as compared with simple steatosis. We identified, by filipin staining, free cholesterol within hepatocyte lipid droplets in patients with NASH and in C57BL/6J mice that developed NASH following a high-fat high-cholesterol diet. Under polarized light these lipid droplets exhibited strong birefringence suggesting that some of the cholesterol was present in the form of crystals. Activated Kupffer cells aggregated around dead hepatocytes that included strongly birefringent cholesterol crystals, forming "crown-like structures" similar to those recently described in inflamed visceral adipose tissue. These Kupffer cells appeared to process the lipid of dead hepatocytes turning it into activated lipid-laden "foam cells" with numerous small cholesterol-containing droplets. In contrast, hepatocyte lipid droplets in patients and mice with simple steatosis did not exhibit cholesterol crystals and their Kupffer cells did not form crown-like structures or transform into foam cells. Our results suggest that cholesterol crystallization within hepatocyte lipid droplets and aggregation and activation of Kupffer cells in crown-like structures around such droplets represent an important, novel mechanism for progression of simple steatosis to NASH. PMID:23417738

  12. Sorafenib prevents liver fibrosis in a non-alcoholic steatohepatitis (NASH) rodent model.

    PubMed

    Stefano, J T; Pereira, I V A; Torres, M M; Bida, P M; Coelho, A M M; Xerfan, M P; Cogliati, B; Barbeiro, D F; Mazo, D F C; Kubrusly, M S; D'Albuquerque, L A C; Souza, H P; Carrilho, F J; Oliveira, C P

    2015-05-01

    Liver fibrosis occurring as an outcome of non-alcoholic steatohepatitis (NASH) can precede the development of cirrhosis. We investigated the effects of sorafenib in preventing liver fibrosis in a rodent model of NASH. Adult Sprague-Dawley rats were fed a choline-deficient high-fat diet and exposed to diethylnitrosamine for 6 weeks. The NASH group (n=10) received vehicle and the sorafenib group (n=10) received 2.5 mg·kg(-1)·day(-1) by gavage. A control group (n=4) received only standard diet and vehicle. Following treatment, animals were sacrificed and liver tissue was collected for histologic examination, mRNA isolation, and analysis of mitochondrial function. Genes related to fibrosis (MMP9, TIMP1, TIMP2), oxidative stress (HSP60, HSP90, GST), and mitochondrial biogenesis (PGC1α) were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR). Liver mitochondrial oxidation activity was measured by a polarographic method, and cytokines by enzyme-linked immunosorbent assay (ELISA). Sorafenib treatment restored mitochondrial function and reduced collagen deposition by nearly 63% compared to the NASH group. Sorafenib upregulated PGC1α and MMP9 and reduced TIMP1 and TIMP2 mRNA and IL-6 and IL-10 protein expression. There were no differences in HSP60, HSP90 and GST expression. Sorafenib modulated PGC1α expression, improved mitochondrial respiration and prevented collagen deposition. It may, therefore, be useful in the treatment of liver fibrosis in NASH. PMID:25714891

  13. Sorafenib prevents liver fibrosis in a non-alcoholic steatohepatitis (NASH) rodent model

    PubMed Central

    Stefano, J.T.; Pereira, I.V.A.; Torres, M.M.; Bida, P.M.; Coelho, A.M.M.; Xerfan, M.P.; Cogliati, B.; Barbeiro, D.F.; Mazo, D.F.C.; Kubrusly, M.S.; D'Albuquerque, L.A.C.; Souza, H.P.; Carrilho, F.J.; Oliveira, C.P.

    2015-01-01

    Liver fibrosis occurring as an outcome of non-alcoholic steatohepatitis (NASH) can precede the development of cirrhosis. We investigated the effects of sorafenib in preventing liver fibrosis in a rodent model of NASH. Adult Sprague-Dawley rats were fed a choline-deficient high-fat diet and exposed to diethylnitrosamine for 6 weeks. The NASH group (n=10) received vehicle and the sorafenib group (n=10) received 2.5 mg·kg-1·day-1 by gavage. A control group (n=4) received only standard diet and vehicle. Following treatment, animals were sacrificed and liver tissue was collected for histologic examination, mRNA isolation, and analysis of mitochondrial function. Genes related to fibrosis (MMP9, TIMP1, TIMP2), oxidative stress (HSP60, HSP90, GST), and mitochondrial biogenesis (PGC1α) were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR). Liver mitochondrial oxidation activity was measured by a polarographic method, and cytokines by enzyme-linked immunosorbent assay (ELISA). Sorafenib treatment restored mitochondrial function and reduced collagen deposition by nearly 63% compared to the NASH group. Sorafenib upregulated PGC1α and MMP9 and reduced TIMP1 and TIMP2 mRNA and IL-6 and IL-10 protein expression. There were no differences in HSP60, HSP90 and GST expression. Sorafenib modulated PGC1α expression, improved mitochondrial respiration and prevented collagen deposition. It may, therefore, be useful in the treatment of liver fibrosis in NASH. PMID:25714891

  14. On Nash Equilibrium and Evolutionarily Stable States That Are Not Characterised by the Folk Theorem

    PubMed Central

    Li, Jiawei; Kendall, Graham

    2015-01-01

    In evolutionary game theory, evolutionarily stable states are characterised by the folk theorem because exact solutions to the replicator equation are difficult to obtain. It is generally assumed that the folk theorem, which is the fundamental theory for non-cooperative games, defines all Nash equilibria in infinitely repeated games. Here, we prove that Nash equilibria that are not characterised by the folk theorem do exist. By adopting specific reactive strategies, a group of players can be better off by coordinating their actions in repeated games. We call it a type-k equilibrium when a group of k players coordinate their actions and they have no incentive to deviate from their strategies simultaneously. The existence and stability of the type-k equilibrium in general games is discussed. This study shows that the sets of Nash equilibria and evolutionarily stable states have greater cardinality than classic game theory has predicted in many repeated games. PMID:26288088

  15. Recent Advances in Understanding of NASH: MicroRNAs as Both Biochemical Markers and Players

    PubMed Central

    Vincent, Robert; Sanyal, Arun

    2014-01-01

    Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatis (NASH) are becoming the dominant liver diseases in the US and Western World. Extensive work is being done to diagnose, understand, and explore the pathogenesis of these multivariable complex diseases. Recently a new avenue of biologic regulation is being explored. MicroRNAs are non-coding RNAs that modulate the expression of multiple genes and have been implicated in multiple diseases. Recently there is a growing body of evidence supporting a significant role of microRNAs in NAFLD pathogenesis and progression to NASH, and hinting at their use as targets, biomarkers and potential therapeutic tools. This review is designed to highlight some of the recent work on a few of the key microRNAs involved in the pathogenesis of NAFLD and NASH. PMID:25574453

  16. Developing Methods for Mapping Soil Moisture in Nash Draw, NM Using RADARSAT 1 SAR Fine Imagery

    NASA Astrophysics Data System (ADS)

    Hossain, A. A.; Easson, G.; Powers, D. W.; Holt, R. M.

    2006-12-01

    Nash Draw, in southeastern NM, is a karst valley that developed in response to subsurface dissolution of evaporites, including halite and sulfate rocks. The hydrologic system within Nash Draw is poorly understood. This study focuses on identifying the distribution and amount of recharge in Nash Draw to assist in understanding the existing processes modifying Nash Draw by solution. We hypothesize that 1) soil moisture contents will be higher in the areas where potential recharge occurs and 2) these areas can be identified using remote sensing. To test the second part of this hypothesis, this study has been designed to determine the spatial and temporal distribution of soil moisture in the study site using microwave data. An area of 225 sq. km in Nash Draw has been selected as the study site. Imagery was acquired from the Alaska SAR Facility (ASF) for 8 scenes of RADARDSAT 1 SAR Fine Beam imagery with different incidence angles (40° and 48°) and imaging modes (ascending and descending). We use RADARDSAT 1 SAR Fine Beam imagery acquired on August 1, 2006 and August 2, 2006 and near real-time ground truth data to develop suitable model to map the spatial distribution of soil moisture in the study site. During the image acquisitions on August 1 and 2, 80 soil samples were collected to determine the near real- time volumetric soil moisture in the study site. Soil samples were collected using a stratified sampling method, and locations of the samples were recorded using GPS. Soil water is compared, using linear regression, to radar backscatter to develop an empirical model of the relationship. The radar backscatter used in this model was acquired at different incidence angles. This study also provides an opportunity to investigate the impact of variable incidence angles on the potential of space-borne active microwave data for soil moisture mapping in semi-arid region like Nash Draw.

  17. Nash equilibrium in differential games and the construction of the programmed iteration method

    SciTech Connect

    Averboukh, Yurii V

    2011-05-31

    This work is devoted to the study of nonzero-sum differential games. The set of payoffs in a situation of Nash equilibrium is examined. It is shown that the set of payoffs in a situation of Nash equilibrium coincides with the set of values of consistent functions which are fixed points of the program absorption operator. A condition for functions to be consistent is given in terms of the weak invariance of the graph of the functions under a certain differential inclusion. Bibliography: 18 titles.

  18. Infinite horizon linear quadratic stochastic Nash differential games of Markov jump linear systems with its application

    NASA Astrophysics Data System (ADS)

    Zhu, Huai-nian; Zhang, Cheng-ke; Bin, Ning

    2014-05-01

    In this paper, we deal with the problem of stochastic Nash differential games of Markov jump linear systems governed by Itô-type equation. Combining the stochastic stabilizability with the stochastic systems, a necessary and sufficient condition for the existence of the Nash strategy is presented by means of a set of cross-coupled stochastic algebraic Riccati equations. Moreover, the stochastic H2/H∞ control for stochastic Markov jump linear systems is discussed as an immediate application and an illustrative example is presented.

  19. Endoscopic Vasectomy of Male Feral Pigeons (Columba livia) as a Possible Method of Population Control.

    PubMed

    Heiderich, Elisabeth; Schildger, Bernd; Lierz, Michael

    2015-03-01

    To evaluate whether single-entry endoscopic vasectomy of male feral pigeons (Columba livia) significantly reduced fertility and would potentially be valuable for control of feral pigeon populations, 252 male feral pigeons were caught in the city of Berne and endoscopically vasectomized. In this procedure, approximately 1 cm of the deferent duct was removed bilaterally. Rapid, uneventful recoveries occurred in 94% (237/252) of the pigeons, whereas 6% (15/252) died because of complications associated with the procedure, consisting of perforation of the ureter (9/15), major hemorrhage (5/15), and respiratory arrest (1/15). Mean anesthesia time was 23±6 minutes. The vasectomized males were habituated to 2 pigeon houses together with fertile females. Another pigeon house with fertile pairs acted as control. All eggs laid were candled weekly to assess fertility. In the 2 pigeon houses with vasectomized males, the mean fertilization rate was 0.9% (5/563), while in the control pigeon house, the rate was 100% (39/39). The results indicate that endoscopic vasectomy of male feral pigeons may be a promising tool for field control of feral pigeon populations, especially in combination with other methods such as pigeon houses. PMID:25867661

  20. Implicit learning in cotton-top tamarins (Saguinus oedipus) and pigeons (Columba livia).

    PubMed

    Locurto, Charles; Fox, Maura; Mazzella, Andrea

    2015-06-01

    There is considerable interest in the conditions under which human subjects learn patterned information without explicit instructions to learn that information. This form of learning, termed implicit or incidental learning, can be approximated in nonhumans by exposing subjects to patterned information but delivering reinforcement randomly, thereby not requiring the subjects to learn the information in order to be reinforced. Following acquisition, nonhuman subjects are queried as to what they have learned about the patterned information. In the present experiment, we extended the study of implicit learning in nonhumans by comparing two species, cotton-top tamarins (Saguinus oedipus) and pigeons (Columba livia), on an implicit learning task that used an artificial grammar to generate the patterned elements for training. We equated the conditions of training and testing as much as possible between the two species. The results indicated that both species demonstrated approximately the same magnitude of implicit learning, judged both by a random test and by choice tests between pairs of training elements. This finding suggests that the ability to extract patterned information from situations in which such learning is not demanded is of longstanding origin. PMID:25673101

  1. Homing pigeons ( Columba livia f. domestica) can use magnetic cues for locating food

    NASA Astrophysics Data System (ADS)

    Thalau, Peter; Holtkamp-Rötzler, Elke; Fleissner, Gerta; Wiltschko, Wolfgang

    2007-10-01

    An experimental group of homing pigeons ( Columba livia f. domestica) learned to associate food with a magnetic anomaly produced by bar magnets that were fixed to the bowl in which they received their daily food ration in their home loft; the control group lacked this experience. Both groups were trained to search for two hidden food depots in a rectangular sand-filled arena without obvious visual cues; for the experimental birds, these depots were also marked with three 1.15 × 106 μT bar magnets. During the tests, there were two food depots, one marked with the magnets, the other unmarked; their position within the arena was changed from test to test. The experimental birds searched within 10 cm of the magnetically marked depot in 49% of the test sessions, whereas the control birds searched there in only 11% of the sessions. Both groups searched near the control depot in 11 and 13% of the sessions, respectively. The significant preference of the magnetically marked food depot by the experimental birds shows that homing pigeons cannot only detect a magnetic anomaly but can also use it as a cue for locating hidden food in an open arena.

  2. Fibrogenesis and Carcinogenesis in Nonalcoholic Steatohepatitis (NASH): Involvement of Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Metalloproteinase (TIMPs)

    PubMed Central

    Okazaki, Isao; Noro, Takuji; Tsutsui, Nobuhiro; Yamanouchi, Eigoro; Kuroda, Hajime; Nakano, Masayuki; Yokomori, Hiroaki; Inagaki, Yutaka

    2014-01-01

    Nonalcoholic steatohepatitis (NASH) is emerging worldwide because life-styles have changed to include much over-eating and less physical activity. The clinical and pathophysiological features of NASH are very different from those of HBV- and HCV-chronic liver diseases. The prognosis of NASH is worse among those with nonalcoholic fatty liver diseases (NAFLD), and some NASH patients show HCC with or without cirrhosis. In the present review we discuss fibrogenesis and the relationship between fibrosis and HCC occurrence in NASH to clarify the role of MMPs and TIMPs in both mechanisms. Previously we proposed MMP and TIMP expression in the multi-step occurrence of HCC from the literature based on viral-derived HCC. We introduce again these expressions during hepatocarcinogenesis and compare them to those in NASH-derived HCC, although the relationship with hepatic stem/progenitor cells (HPCs) invasion remains unknown. Signal transduction of MMPs and TIMPs is also discussed because it is valuable for the prevention and treatment of NASH and NASH-derived HCC. PMID:24978432

  3. Efficient Nash Equilibrium Resource Allocation Based on Game Theory Mechanism in Cloud Computing by Using Auction

    PubMed Central

    Nezarat, Amin; Dastghaibifard, GH

    2015-01-01

    One of the most complex issues in the cloud computing environment is the problem of resource allocation so that, on one hand, the cloud provider expects the most profitability and, on the other hand, users also expect to have the best resources at their disposal considering the budget constraints and time. In most previous work conducted, heuristic and evolutionary approaches have been used to solve this problem. Nevertheless, since the nature of this environment is based on economic methods, using such methods can decrease response time and reducing the complexity of the problem. In this paper, an auction-based method is proposed which determines the auction winner by applying game theory mechanism and holding a repetitive game with incomplete information in a non-cooperative environment. In this method, users calculate suitable price bid with their objective function during several round and repetitions and send it to the auctioneer; and the auctioneer chooses the winning player based the suggested utility function. In the proposed method, the end point of the game is the Nash equilibrium point where players are no longer inclined to alter their bid for that resource and the final bid also satisfies the auctioneer’s utility function. To prove the response space convexity, the Lagrange method is used and the proposed model is simulated in the cloudsim and the results are compared with previous work. At the end, it is concluded that this method converges to a response in a shorter time, provides the lowest service level agreement violations and the most utility to the provider. PMID:26431035

  4. Efficient Nash Equilibrium Resource Allocation Based on Game Theory Mechanism in Cloud Computing by Using Auction.

    PubMed

    Nezarat, Amin; Dastghaibifard, G H

    2015-01-01

    One of the most complex issues in the cloud computing environment is the problem of resource allocation so that, on one hand, the cloud provider expects the most profitability and, on the other hand, users also expect to have the best resources at their disposal considering the budget constraints and time. In most previous work conducted, heuristic and evolutionary approaches have been used to solve this problem. Nevertheless, since the nature of this environment is based on economic methods, using such methods can decrease response time and reducing the complexity of the problem. In this paper, an auction-based method is proposed which determines the auction winner by applying game theory mechanism and holding a repetitive game with incomplete information in a non-cooperative environment. In this method, users calculate suitable price bid with their objective function during several round and repetitions and send it to the auctioneer; and the auctioneer chooses the winning player based the suggested utility function. In the proposed method, the end point of the game is the Nash equilibrium point where players are no longer inclined to alter their bid for that resource and the final bid also satisfies the auctioneer's utility function. To prove the response space convexity, the Lagrange method is used and the proposed model is simulated in the cloudsim and the results are compared with previous work. At the end, it is concluded that this method converges to a response in a shorter time, provides the lowest service level agreement violations and the most utility to the provider. PMID:26431035

  5. Acute, fatal Sarcocystis calchasi-associated hepatitis in Roller pigeons (Columba livia f. dom.) at Philadelphia Zoo.

    PubMed

    Trupkiewicz, J G; Calero-Bernal, R; Verma, S K; Mowery, J; Davison, S; Habecker, P; Georoff, T A; Ialeggio, D M; Dubey, J P

    2016-01-30

    Four Roller pigeons (Columba livia f. dom.) at the Philadelphia Zoo died suddenly. Necropsy examination revealed macroscopic hepatitis. Microscopically, the predominant lesions were in liver, characterized with necrosis and mixed cell inflammatory response. Sarcocystis calchasi-like schizonts and free merozoites were identified in liver. Transmission electron microscopy confirmed that schizonts were in hepatocytes. A few schizonts were in spleen. PCR using S. calchasi-specific primers confirmed the diagnosis. Neither lesions nor protozoa were found in brain and muscles. This is the first report of acute visceral S. calchasi-associated sarcocystosis in naturally infected avian hosts. PMID:26801595

  6. Monitoring air pollution at Mohammedia (Morocco): Pb, Cd and Zn in the blood of pigeons (Columba livia).

    PubMed

    Kouddane, N; Mouhir, L; Fekhaoui, M; Elabidi, A; Benaakame, R

    2016-05-01

    The concentrations of Pb, Cd and Zn were investigated in the blood of pigeons (Columba livia) in order to assess the degree of pollution by heavy metal. For this, wild city pigeons were caught at four different locations in Mohammedia classified according to their industrial activity and road traffic density. Significant difference in heavy metal concentrations were observed between sites studied, the highest lead and cadmium levels were found in industrial area and center town, while the highest zinc level was found in the less contaminated area. These results indicate that the industrial activities and the road traffic are the most important source of pollution. PMID:26903169

  7.  NASH: A glance at the landscape of pharmacological treatment.

    PubMed

    Brodosi, Lucia; Marchignoli, Francesca; Petroni, Maria Letizia; Marchesini, Giulio

    2016-01-01

     The role of nonalcoholic fatty liver disease, namely nonalcoholic steatohepatitis (NASH), as risk factor for liver- and non-liver-related morbidity and mortality has been extensively reported. In addition to lifestyle changes, capable of removing the metabolic factors driving disease progression, there is an urgent need for drugs able to reduce hepatic necroinflammation without worsening of fibrosis. This goal is considered by regulatory agencies as surrogate marker to define the effectiveness in pharmacological compounds in NASH, and fast-track approval was granted by the Food and Drug Administration in consideration of disease severity and unmet medical needs. Several compounds are in the pipeline of pharmaceutical industries and are being studied in phase II trials, but only a few (obeticholic acid, elafibranor) have started phase III trials. This concise review is intended to offer a systematic analysis of the most promising therapeutic intervention in NASH. In conclusion, there is reasonable expectation that drug may help curb the burden of NASH, and we look forward to obtaining solid data on their long-term safety and effectiveness. However, we should not forget that behavioral interventions remain a mandatory background treatment, able to stop disease progression in compliant overweight/ obese patients, with results that compare favorably with - and add to - the beneficial effects of drug treatment. PMID:27493105

  8. Protein kinase STK25 regulates hepatic lipid partitioning and progression of liver steatosis and NASH.

    PubMed

    Amrutkar, Manoj; Cansby, Emmelie; Nuñez-Durán, Esther; Pirazzi, Carlo; Ståhlman, Marcus; Stenfeldt, Elin; Smith, Ulf; Borén, Jan; Mahlapuu, Margit

    2015-04-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common form of liver disease, and 10% to 20% of NAFLD patients progress to nonalcoholic steatohepatitis (NASH). The molecular pathways controlling progression to NAFLD/NASH remain poorly understood. We recently identified serine/threonine protein kinase 25 (STK25) as a regulator of whole-body insulin and glucose homeostasis. This study investigates the role of STK25 in liver lipid accumulation and NASH. Stk25 transgenic mice challenged with a high-fat diet displayed a dramatic increase in liver steatosis and hepatic insulin resistance compared to wild-type siblings. Focal fibrosis, hepatocellular damage, and inflammation were readily seen in transgenic but not wild-type livers. Transgenic livers displayed reduced β-oxidation and triacylglycerol secretion, while lipid uptake and synthesis remained unchanged. STK25 was associated with lipid droplets, colocalizing with the main hepatic lipid droplet-coating protein adipose differentiation-related protein, the level of which was increased 3.8 ± 0.7-fold in transgenic livers (P < 0.01), while a key hepatic lipase, adipose triacylglycerol lipase, was translocated from the lipid droplets surface to the cytoplasm, providing the likely mechanism underlying the effect of STK25. In summary, STK25 is a lipid droplet-associated protein that promotes NAFLD through control of lipid release from the droplets for β-oxidation and triacylglycerol secretion. STK25 also drives pathogenesis of NASH. PMID:25609431

  9. Two Different Approaches to Nonzero-Sum Stochastic Differential Games

    SciTech Connect

    Rainer, Catherine

    2007-06-15

    We make the link between two approaches to Nash equilibria for nonzero-sum stochastic differential games: the first one using backward stochastic differential equations and the second one using strategies with delay. We prove that, when both exist, the two notions of Nash equilibria coincide.

  10. Quality of Life in Adults with Nonalcoholic Fatty Liver Disease: Baseline Data from the NASH CRN

    PubMed Central

    David, Kristin; Kowdley, Kris V.; Unalp, Aynur; Kanwal, Fasiha; Brunt, Elizabeth M.; Schwimmer, Jeffrey B.

    2009-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States. The association between NAFLD and quality of life (QOL) remains unclear. These data are important to estimate the burden of illness in NAFLD. The aim was to report QOL scores of adults with NAFLD, and examine the association between NAFLD severity and QOL. QOL data were collected from adults with NAFLD enrolled in the NASH Clinical Research Network using the SF-36 survey and scores were compared to normative U.S. population scores. Liver biopsy histology was reviewed by a central pathology committee. A total of 713 subjects with NAFLD (M=269, F=444) were included. Mean age of subjects was 48.3 years; 61% had definite NASH, and 28% had bridging fibrosis or cirrhosis. Diabetes was present in 27% of subjects. Subjects with NAFLD had worse physical (mean=45.2) and mental health scores (mean=47.6) compared to the U.S. population with (mean=50) and without (physical: 55.8, mental: 52.5) chronic illness. Subjects with NASH reported lower physical health compared to subjects with fatty liver disease without NASH (44.5 vs. 47.1, p=.02). Subjects with cirrhosis had significantly (P<0.001) poorer physical health scores (38.4) vs. subjects with no (47.6), mild (46.2), moderate (44.6) or bridging fibrosis (44.6). Cirrhosis was associated with poorer physical health after adjusting for potential confounders. Mental health scores did not differ between participants with and without NASH or by degree of fibrosis. Conclusion Adults with NAFLD have a significant decrement in QOL. Treatment of NAFLD should incorporate strategies to improve QOL, especially physical health. PMID:19434741

  11. Pigeons (Columba livia) as Trainable Observers of Pathology and Radiology Breast Cancer Images

    PubMed Central

    Levenson, Richard M.; Krupinski, Elizabeth A.; Navarro, Victor M.; Wasserman, Edward A.

    2015-01-01

    Pathologists and radiologists spend years acquiring and refining their medically essential visual skills, so it is of considerable interest to understand how this process actually unfolds and what image features and properties are critical for accurate diagnostic performance. Key insights into human behavioral tasks can often be obtained by using appropriate animal models. We report here that pigeons (Columba livia)—which share many visual system properties with humans—can serve as promising surrogate observers of medical images, a capability not previously documented. The birds proved to have a remarkable ability to distinguish benign from malignant human breast histopathology after training with differential food reinforcement; even more importantly, the pigeons were able to generalize what they had learned when confronted with novel image sets. The birds’ histological accuracy, like that of humans, was modestly affected by the presence or absence of color as well as by degrees of image compression, but these impacts could be ameliorated with further training. Turning to radiology, the birds proved to be similarly capable of detecting cancer-relevant microcalcifications on mammogram images. However, when given a different (and for humans quite difficult) task—namely, classification of suspicious mammographic densities (masses)—the pigeons proved to be capable only of image memorization and were unable to successfully generalize when shown novel examples. The birds’ successes and difficulties suggest that pigeons are well-suited to help us better understand human medical image perception, and may also prove useful in performance assessment and development of medical imaging hardware, image processing, and image analysis tools. PMID:26581091

  12. Pigeons (Columba livia) as Trainable Observers of Pathology and Radiology Breast Cancer Images.

    PubMed

    Levenson, Richard M; Krupinski, Elizabeth A; Navarro, Victor M; Wasserman, Edward A

    2015-01-01

    Pathologists and radiologists spend years acquiring and refining their medically essential visual skills, so it is of considerable interest to understand how this process actually unfolds and what image features and properties are critical for accurate diagnostic performance. Key insights into human behavioral tasks can often be obtained by using appropriate animal models. We report here that pigeons (Columba livia)-which share many visual system properties with humans-can serve as promising surrogate observers of medical images, a capability not previously documented. The birds proved to have a remarkable ability to distinguish benign from malignant human breast histopathology after training with differential food reinforcement; even more importantly, the pigeons were able to generalize what they had learned when confronted with novel image sets. The birds' histological accuracy, like that of humans, was modestly affected by the presence or absence of color as well as by degrees of image compression, but these impacts could be ameliorated with further training. Turning to radiology, the birds proved to be similarly capable of detecting cancer-relevant microcalcifications on mammogram images. However, when given a different (and for humans quite difficult) task-namely, classification of suspicious mammographic densities (masses)-the pigeons proved to be capable only of image memorization and were unable to successfully generalize when shown novel examples. The birds' successes and difficulties suggest that pigeons are well-suited to help us better understand human medical image perception, and may also prove useful in performance assessment and development of medical imaging hardware, image processing, and image analysis tools. PMID:26581091

  13. Discovery and characterization of the first genuine avian leptin gene in the rock dove (Columba livia).

    PubMed

    Friedman-Einat, Miriam; Cogburn, Larry A; Yosefi, Sara; Hen, Gideon; Shinder, Dmitry; Shirak, Andrey; Seroussi, Eyal

    2014-09-01

    Leptin, the key regulator of mammalian energy balance, has been at the center of a great controversy in avian biology for the last 15 years since initial reports of a putative leptin gene (LEP) in chickens. Here, we characterize a novel LEP in rock dove (Columba livia) with low similarity of the predicted protein sequence (30% identity, 47% similarity) to the human ortholog. Searching the Sequence-Read-Archive database revealed leptin transcripts, in the dove's liver, with 2 noncoding exons preceding 2 coding exons. This unusual 4-exon structure was validated by sequencing of a GC-rich product (76% GC, 721 bp) amplified from liver RNA by RT-PCR. Sequence alignment of the dove leptin with orthologous leptins indicated that it consists of a leader peptide (21 amino acids; aa) followed by the mature protein (160 aa), which has a putative structure typical of 4-helical-bundle cytokines except that it is 12 aa longer than human leptin. Extra residues (10 aa) were located within the loop between 2 5'-helices, interrupting the amino acid motif that is conserved in tetrapods and considered essential for activation of leptin receptor (LEPR) but not for receptor binding per se. Quantitative RT-PCR of 11 tissues showed highest (P < .05) expression of LEP in the dove's liver, whereas the dove LEPR peaked (P < .01) in the pituitary. Both genes were prominently expressed in the gonads and at lower levels in tissues involved in mammalian leptin signaling (adipose; hypothalamus). A bioassay based on activation of the chicken LEPR in vitro showed leptin activity in the dove's circulation, suggesting that dove LEP encodes an active protein, despite the interrupted loop motif. Providing tools to study energy-balance control at an evolutionary perspective, our original demonstration of leptin signaling in dove predicts a more ancient role of leptin in growth and reproduction in birds, rather than appetite control. PMID:24758303

  14. Defensive behaviors and prosencephalic neurogenesis in pigeons (Columba livia) are affected by environmental enrichment in adulthood.

    PubMed

    Melleu, F F; Pinheiro, M V; Lino-de-Oliveira, C; Marino-Neto, J

    2016-05-01

    Neurogenesis in the adult brain appears to be phylogenetically conserved across the animal kingdom. In pigeons and other adult non-oscine birds, immature neurons are observed in several prosencephalic areas, suggesting that neurogenesis may participate in the control of different behaviors. The mechanisms controlling neurogenesis and its relevance to defensive behaviors in non-oscine birds remain elusive. Herein, the contribution of the environment to behavior and neurogenesis of pigeons was investigated. Adult pigeons (Columba livia, n = 6/group), housed in standard (SE) or enriched environment (EE) for 42 days, were exposed to an unfamiliar environment (UE) followed by presentation to a novel object (NO). Video recordings of UE+NO tests were analyzed and scored for latency, duration and frequency of angular head movements, peeping, grooming, immobility and locomotion. Twenty-four hours later, pigeons were submitted to the tonic immobility test (TI) and number of trials for TI and TI duration were scored, followed by euthanasia 2 h later. Brains were immunohistochemically processed to reveal doublecortin (DCX), a marker for newborn neurons. Compared to those housed in SE, the pigeons housed in EE responded to a NO with more immobility. In addition, the pigeons housed in EE presented longer TI, more DCX-immunoreactive (DCX-ir) cells in the hippocampus and fewer DCX-ir cells in the lateral striatum than those housed in SE. There was no correlation between the number of DCX-ir cells and the scores of immobility in behavioral tests. Together, these data suggest that enrichment favored behavioral inhibition and neurogenesis in the adult pigeons through different, parallel mechanisms. PMID:25869276

  15. Muscle function during takeoff and landing flight in the pigeon (Columba livia).

    PubMed

    Robertson, Angela M Berg; Biewener, Andrew A

    2012-12-01

    This study explored the muscle strain and activation patterns of several key flight muscles of the pigeon (Columba livia) during takeoff and landing flight. Using electromyography (EMG) to measure muscle activation, and sonomicrometry to quantify muscle strain, we evaluated the muscle function patterns of the pectoralis, biceps, humerotriceps and scapulotriceps as pigeons flew between two perches. These recordings were analyzed in the context of three-dimensional wing kinematics. To understand the different requirements of takeoff, midflight and landing, we compared the activity and strain of these muscles among the three flight modes. The pectoralis and biceps exhibited greater fascicle strain rates during takeoff than during midflight or landing. However, the triceps muscles did not exhibit notable differences in strain among flight modes. All observed strain, activation and kinematics were consistent with hypothesized muscle functions. The biceps contracted to stabilize and flex the elbow during the downstroke. The humerotriceps contracted to extend the elbow at the upstroke-downstroke transition, followed by scapulotriceps contraction to maintain elbow extension during the downstroke. The scapulotriceps also appeared to contribute to humeral elevation. Greater muscle activation intensity was observed during takeoff, compared with mid-flight and landing, in all muscles except the scapulotriceps. The timing patterns of muscle activation and length change differed among flight modes, yet demonstrated that pigeons do not change the basic mechanical actions of key flight muscles as they shift from flight activities that demand energy production, such as takeoff and midflight, to maneuvers that require absorption of energy, such as landing. Similarly, joint kinematics were consistent among flight modes. The stereotypy of these neuromuscular and joint kinematic patterns is consistent with previously observed stereotypy of wing kinematics relative to the pigeon's body

  16. Definition and natural history of metabolic steatosis: clinical aspects of NAFLD, NASH and cirrhosis.

    PubMed

    Serfaty, L; Lemoine, M

    2008-12-01

    Metabolic steatosis or non-alcoholic fatty liver (NAFLD) is the most common cause of chronic liver injury in Western countries. Histological signs of necroinflammation, indicating the presence of non-alcoholic steatohepatitis (NASH), are present in 20-30% of cases. While steatosis on its own has a benign course, NASH may be associated with fibrosis and may progress to cirrhosis, terminal liver failure and hepatocellular carcinoma. NAFLD is closely associated with the metabolic syndrome, its prevalence reaching 50-90% in obese patients. The clinical impact of NAFLD has been demonstrated in large cohort studies by the overprevalence of cirrhosis and hepatocellular carcinoma in obese and diabetic patients. In terms of survival, liver disease is the third most common cause of mortality in patients with NAFLD. When associated with other causes of liver disease such as alcohol consumption or hepatitis C infection, metabolic steatosis may be a major risk factor for disease progression. PMID:19195623

  17. MicroRNA Expression Relating to Dietary-Induced Liver Steatosis and NASH

    PubMed Central

    Zarfeshani, Aida; Ngo, Sherry; Sheppard, Allan M.

    2015-01-01

    Health issues associated with excessive caloric intake and sedentary lifestyle are driving a modern “epidemic” of liver disease. Initially presenting in the clinic as an excessive accumulation of fat within hepatocyte cells (steatosis), the progression to more severe non-alcoholic steatohepatitis (NASH) in which liver damage and inflammation are overt features, is becoming increasingly common. Often developing as a sequela of obesity, non-alcoholic fatty liver disease (NAFLD) arises in almost one-third of people initially carrying excess hepatic fat and is likely the result of the liver’s limited capacity to cope with the modern-day levels of dietary fatty acids circulating in the blood. While routine imaging can readily assess the presence and level of “extra-hepatic fat”, a proper diagnosis of disease progression to NASH is currently only possible by liver biopsy. A general reluctance to undergo such screening means that the prevalence of NASH is likely to be under reported and, thus, risk assessment for future metabolic syndrome (MetS) markedly compromised. The seemingly inevitable progression to overt insulin resistance that characterizes MetS may in part be the consequence of the body’s attempt to cope with NAFLD by driving systemic insulin sensitivity and, thus, fatty acid breakdown. The potential significance of miRNAs in both physiological homeostasis and pathogenesis is increasingly appreciated and in the liver may contribute specifically to the regulation of lipid pathways and NAFLD progression. As such, they may have utility as molecular indicators for the accurate profiling of both initial risk and disease progression from simple steatosis to NASH, and further to fibrosis/cirrhosis. PMID:26580662

  18. Transforming the Ordinary into Extraordinary: Gary Nash and the Visions of History

    ERIC Educational Resources Information Center

    Vigilante, David

    2009-01-01

    Through his long career, Gary Nash has been a pioneer in opening the often-stuffy chambers of academia. He has shown a devotion to K-12 teachers throughout the nation and has ventured into their classrooms to observe, to teach, and, yes, to learn. It is all too rare for a noted historian, famous for his many seminal works, to roll up his sleeves…

  19. Photocurrents in retinal rods of pigeons (Columba livia): kinetics and spectral sensitivity.

    PubMed Central

    Palacios, A G; Goldsmith, T H

    1993-01-01

    1. Membrane photocurrents were recorded from outer segments of isolated retinal rods of pigeons (Columba livia), the first such measurements on the photoreceptors of a bird. The amplitude of the response to 20 ms flashes of narrow wavelength bands of light increases linearly with intensity at low photon fluxes and saturates at higher intensities. The maximum (saturating) photocurrent observed in forty-nine rod cells was 50 pA. Larger responses with less variability in the intensity for half-maximal responses were observed when the physiological saline contained 20 mM bicarbonate (in addition to Hepes buffer). 2. The dependence of peak amplitude on intensity is well fitted by an exponential function; it is usually less well fitted by the Michaelis-Menten (Naka-Rushton) equation. 3. In the presence of bicarbonate, the average sensitivity of pigeon rods to dim flashes was 0.56 pA photon-1 microns -2. The effective collecting area per photon was 1.8 microns 2. About 83 +/- 26 (mean +/- S.D.) photoisomerizations were required for a half-saturating response. 4. The response kinetics of rods to dim flashes can be reasonably well described by a series of four to five either Poisson or independent filters. The time to peak, measured from the mid-point of a 20 ms flash, was 319 +/- 83 ms (mean +/- S.D.). The integration time of the response was 851 +/- 86 ms (mean +/- S.D.) with bicarbonate present and 572 +/- 126 ms in the absence of bicarbonate. The responses of pigeon rods appear to be slower than those of mammals at the same temperature. The fraction of current suppressed by a single photoisomerization is smaller in pigeon than in mammalian rods by a factor of at least two. 5. The spectral sensitivity function was measured between 680 and 330 nm. The maximum at about 505 nm (range 497-508 nm) corresponds to the alpha-band of a vertebrate rhodopsin and agrees with previous behavioural measurements of scotopic sensitivity of pigeons as well as the absorption spectrum of

  20. Liver Injury Indicating Fatty Liver but Not Serologic NASH Marker Improves under Metformin Treatment in Polycystic Ovary Syndrome

    PubMed Central

    Tan, Susanne; Vollmar, Nils; Benson, Sven; Sowa, Jan-Peter; Bechmann, Lars P.; Gerken, Guido; Fuhrer, Dagmar; Canbay, Ali

    2015-01-01

    Objective. Polycystic ovary syndrome (PCOS) is associated with obesity and insulin resistance (IR), key features of nonalcoholic steatohepatitis (NASH). Cytokeratin 18 fragments (M30) have been established as a serum marker for NASH. The insulin sensitizer metformin improves hepatic IR. This study evaluates the influence of MF on serologic NASH (sNASH) in patients with PCOS. Patients and Methods. In 89 patients, metabolic parameters, liver injury indicating fatty liver (LIFL), and M30 were assessed at baseline and after metformin treatment. Patients with initial IR were subdivided into dissolved (PCOS-exIR) and persistent IR (PCOS-PIR) after treatment and compared to an initially insulin sensitive PCOS group (PCOS-C). Results. Improvement of LIFL prevalence could be seen in PCOS-C and PCOS-exIR compared to PCOS-PIR (−19.4, resp., −12.0% versus 7.2%, Chi2 = 29.5, P < 0.001) without change in sNASH prevalence. In PCOS-PIR, ALT levels increased significantly accompanied by a nominal, nonsignificant M30 increase. Conclusions. Metformin improves LIFL in subgroups of patients with PCOS without influencing sNASH. This could either indicate a missing effect of metformin on NAFLD or slowed disease progression. Further studies are needed to elucidate NAFLD in the context of PCOS and potential therapeutic options. PMID:25873949

  1. Insulin resistance and clinical aspects of non-alcoholic steatohepatitis (NASH).

    PubMed

    Agarwal, Naresh; Sharma, Barjesh Chander

    2005-10-01

    Non-alcoholic steatohepatitis (NASH) is one of the most common liver disorders. This is highly prevalent in obese and diabetic subjects. Persons with central obesity are at particular risk. Other clinical predictors are age more than 40-50 years and hyperlipidemias, but none of these factors is invariable for causation of NASH. Other reported associations are, celiac disease, Wilson's Disease and few other metabolic diseases. Drugs, particularly amiodarone, tamoxifen, nucleoside analogues and methotrxate have also been linked to NASH. The disease is evenly distributed in both sexes but advanced disease is more common in women. Ethnic variation exists and African Americans are less affected than Hispanic Americans. Specific clinical features of NASH are infrequent. Patients usually come to clinical attention by elevated liver enzymes found on routine evaluation but on history, about two third of patients will admit to have mild fatigue and about half will report right upper quadrant pain. Rarely, patient may present with a complication of cirrhosis. Physical examination may reveal hepatomegaly and splenomegaly. Research in last few years has stressed that development of steatosis, stetohepatitis, fibrosis with subsequent cirrhosis are most probably the result of insulin resistance. Therefore, clinical features may reflect existence of insulin resistance. Obesity, particularly central obesity is most important of these. Patients may have sleep apnea syndrome. Hypertension and manifestations of diabetes mellitus like polyuria, polydypsia, and neurological deficits may occur. Patients may have varying combination of obesity, diabetes, hyperlipidemia, hypertension and impaired fibrinolysis (syndrome X). Children with insulin resistance may show acanthosis nigricance. Patients with polycystic ovary syndrome, which consists of insulin resistance, diabetes, obesity, hirsutism, oligo or polymenorrha and hyperlipidemia may have NASH. Other rare manifestations of insulin

  2. Detection of carcinogenic etheno-DNA adducts in children and adolescents with non-alcoholic steatohepatitis (NASH)

    PubMed Central

    Teufel, Ulrike; Peccerella, Teresa; Engelmann, Guido; Bruckner, Thomas; Flechtenmacher, Christa; Millonig, Gunda; Stickel, Felix; Hoffmann, Georg F.; Schirmacher, Peter; Mueller, Sebastian; Bartsch, Helmut

    2015-01-01

    Background Carcinogenic exocyclic-DNA adducts like 1,N6-etheno-2'-deoxyadenosine (εdA) are formed through reactive intermediates of 4-hydroxynonenal (4-HNE) or other lipid peroxidation (LPO) products with the DNA bases A, C, methyl-C and G. High levels of hepatic etheno-DNA adducts have been detected in cancer prone liver diseases including alcoholic liver disease (ALD). In ALD εdA levels correlated significantly with cytochrome P-450 2E1 (CYP2E1) expression which is also induced in non-alcoholic steatohepatitis (NASH). We investigated the occurrence of εdA adducts in children with NASH as a DNA damage marker. Methods Liver biopsies from 21 children/adolescents with histologically proven NASH were analysed for hepatic fat content, inflammation, and fibrosis. εdA levels in DNA, CYP2E1-expression and protein bound 4-hydroxynonenal (HNE) were semi-quantitatively evaluated by immunohistochemistry. Results Among 21 NASH children, εdA levels in the liver were high in 3, moderate in 5, weak in 9 and not elevated in 4 patients. There was a positive correlation between CYP2E1 and protein-bound 4-HNE (r=0.60; P=0.008) and a trend for a positive relationship for CYP2E1 vs. staining intensity of εdA (r=0.45; P=0.06). Inflammatory activity and fibrosis correlated significantly (r=0.49, P=0.023). Conclusions Our results demonstrate for the first time the presence of elevated carcinogenic etheno-DNA lesions (εdA) in the majority (17/21) of liver biopsies from young NASH patients. Our data suggest that LPO-derived etheno-adducts are implicated in NASH. Whether these adducts may serve as predictive risk markers in NASH children to develop hepatocellular cancer later in life remains to be investigated. PMID:26734629

  3. Reliability and validity of the Chronic Liver Disease Questionnaire (CLDQ) in adults with non-alcoholic steatohepatitis (NASH)

    PubMed Central

    Chawla, Kashmira S; Talwalkar, Jayant A; Keach, Jill C; Malinchoc, Michael; Lindor, Keith D; Jorgensen, Roberta

    2016-01-01

    Introduction Significant impairments in health-related quality of life (HRQL) in patients with non-alcoholic fatty liver disease have been previously described. The disease-specific HRQL among patients with non-alcoholic steatohepatitis (NASH), however, remains unknown. Aim To determine the degree of construct validity of the Chronic Liver Disease Questionnaire (CLDQ) in adults with NASH. Methods Participants referred for the evaluation of histology-proven NASH at Mayo Clinic, Rochester, between 1996 and 2000, were evaluated. HRQL assessment by the Short-Form 36 (SF-36) Health Survey and CLD) was performed. The primary outcome was to determine the level of correlation between overall and subscale scores for the CLDQ and SF-36 instruments. Results Among 79 participants (70%) with NASH completing both questionnaires (mean age, 51.2 years with 64% female gender), excellent reliability was noted for the CLDQ instrument. Significant reductions in all SF-36 domains (p<0.05 for all) including PCS and MCS scores (p<0.02 for both) among participants with NASH compared with normative data from an age-matched and sex-matched US general population sample was observed. Highly significant correlations were observed between overall CLDQ score with SF-36 PCS (r=0.82, p<0.0001) and SF-36 MCS (r=0.67, p<0.0001) scores. Similar degrees of correlation were observed between relevant subscales of the CLDQ and SF-36 as well. Discussion The CLDQ has excellent reliability and validity of construct for HRQL assessment in adults with NASH when compared with the SF-36. Future investigations among participants with NASH require assessing the responsiveness of the CLDQ to medical therapies and disease progression. PMID:27110379

  4. Nash Equilibria and the Price of Anarchy for Flows over Time

    NASA Astrophysics Data System (ADS)

    Koch, Ronald; Skutella, Martin

    We study Nash equilibria in the context of flows over time. Many results on static routing games have been obtained over the last ten years. In flows over time (also called dynamic flows), flow travels through a network over time and, as a consequence, flow values on edges are time-dependent. This more realistic setting has not been tackled from the viewpoint of algorithmic game theory yet; but there is a rich literature on game theoretic aspects of flows over time in the traffic community.

  5. General quantum two-player games, their gate operators, and Nash equilibria

    NASA Astrophysics Data System (ADS)

    Bolonek-Lasoń, Katarzyna

    2015-02-01

    Two-player N-strategy games quantized according to the Eisert-Lewenstein-Wilkens scheme [Phys. Rev. Lett. 83, 3077 (1999)] are considered. Group-theoretical methods are applied to the problem of finding a general form of gate operators (entanglers) under the assumption that the set of classical pure strategies is contained in the set of pure quantum ones. The role of the stability group of the initial state of the game is stressed. As an example, it is shown that maximally entangled games do not admit nontrivial pure Nash strategies. The general arguments are supported by explicit computations performed in the three-strategy case.

  6. Implications of worse renal dysfunction and medical comorbidities in patients with NASH undergoing liver transplant evaluation: impact on MELD and more.

    PubMed

    Park, Chan W; Tsai, Naoky T; Wong, Linda L

    2011-01-01

    Increasing numbers of patients with non-alcoholic steatohepatitis (NASH) are referred for liver transplant (LT). Our objective was to characterize patients with NASH among referred LT candidates (from 1998 to 2008), and we compared demographics, etiology of liver disease, diabetes, hypertension, smoking, obesity, cardiac disease, cancer, laboratory data, model for end-stage liver disease (MELD), and outcomes between NASH and non-NASH patients. Patients with NASH (n = 71) were compared to other chronic liver disease (n = 472). Patients with NASH were older (58.7 vs. 52.5 yr, p < 0.0001), Asian (53.5% vs. 34.7%, p = 0.03) and women (50.7% vs. 32.1%, p = 0.003). Patients with NASH had more diabetes, hypertension, obesity, cardiac disease, and smoking history (p < 0.05). Patients with NASH were equally likely to have liver cancer, but more likely to have non-liver cancers (20.8% vs. 4.4%, p = 0.008). There was no difference in MELD, but patients with NASH had lower protime/international normalized ratio (1.14 vs. 1.27, p = 0.04) and higher creatinine (1.26 vs. 0.98 mg/dL, p = 0.0018). Patients with NASH were equally likely to undergo evaluation, listing, and transplantation compared to non-NASH patients. While all patients with chronic liver disease can have renal dysfunction because of hepatorenal syndrome, patients with NASH have more renal dysfunction, perhaps related to diabetes, hypertension, and cardiovascular disease. Transplant centers should consider this carefully in selection of candidates for LT. PMID:21958082

  7. Kupffer Cells Undergo Fundamental Changes during the Development of Experimental NASH and Are Critical in Initiating Liver Damage and Inflammation.

    PubMed

    Reid, D T; Reyes, J L; McDonald, B A; Vo, T; Reimer, R A; Eksteen, B

    2016-01-01

    Non-alcoholic fatty liver disease has become the leading liver disease in North America and is associated with the progressive inflammatory liver disease non-alcoholic steatohepatitis (NASH). Considerable effort has been made to understand the role of resident and recruited macrophage populations in NASH however numerous questions remain. Our goal was to characterize the dynamic changes in liver macrophages during the initiation of NASH in a murine model. Using the methionine-choline deficient diet we found that liver-resident macrophages, Kupffer cells were lost early in disease onset followed by a robust infiltration of Ly-6C+ monocyte-derived macrophages that retained a dynamic phenotype. Genetic profiling revealed distinct patterns of inflammatory gene expression between macrophage subsets. Only early depletion of liver macrophages using liposomal clodronate prevented the development of NASH in mice suggesting that Kupffer cells are critical for the orchestration of inflammation during experimental NASH. Increased understanding of these dynamics may allow us to target potentially harmful populations whilst promoting anti-inflammatory or restorative populations to ultimately guide the development of effective treatment strategies. PMID:27454866

  8. Prohibitin-induced, obesity-associated insulin resistance and accompanying low-grade inflammation causes NASH and HCC.

    PubMed

    Ande, Sudharsana R; Nguyen, K Hoa; Grégoire Nyomba, B L; Mishra, Suresh

    2016-01-01

    Obesity increases the risk for nonalcoholic steatohepatitis (NASH) and hepatocarcinogenesis. However, the underlying mechanisms involved in the disease process remain unclear. Recently, we have developed a transgenic obese mouse model (Mito-Ob) by prohibitin mediated mitochondrial remodeling in adipocytes. The Mito-Ob mice develop obesity in a sex-neutral manner, but obesity-associated adipose inflammation and metabolic dysregulation in a male sex-specific manner. Here we report that with aging, the male Mito-Ob mice spontaneously develop obesity-linked NASH and hepatocellular carcinoma (HCC). In contrast, the female Mito-Ob mice maintained normal glucose and insulin levels and did not develop NASH and HCC. The anti-inflammatory peptide ghrelin was significantly upregulated in the female mice and down regulated in the male mice compared with respective control mice. In addition, a reduction in the markers of mitochondrial content and function was found in the liver of male Mito-Ob mice with NASH/HCC development. We found that ERK1/2 signaling was significantly upregulated whereas STAT3 signaling was significantly down regulated in the tumors from Mito-Ob mice. These data provide a proof-of-concept that the metabolic and inflammatory status of the adipose tissue and their interplay at the systemic and hepatic level play a central role in the pathogenesis of obesity-linked NASH and HCC. PMID:27005704

  9. Kupffer Cells Undergo Fundamental Changes during the Development of Experimental NASH and Are Critical in Initiating Liver Damage and Inflammation

    PubMed Central

    Reid, D. T.; Reyes, J. L.; McDonald, B. A.; Vo, T.; Reimer, R. A.; Eksteen, B.

    2016-01-01

    Non-alcoholic fatty liver disease has become the leading liver disease in North America and is associated with the progressive inflammatory liver disease non-alcoholic steatohepatitis (NASH). Considerable effort has been made to understand the role of resident and recruited macrophage populations in NASH however numerous questions remain. Our goal was to characterize the dynamic changes in liver macrophages during the initiation of NASH in a murine model. Using the methionine-choline deficient diet we found that liver-resident macrophages, Kupffer cells were lost early in disease onset followed by a robust infiltration of Ly-6C+ monocyte-derived macrophages that retained a dynamic phenotype. Genetic profiling revealed distinct patterns of inflammatory gene expression between macrophage subsets. Only early depletion of liver macrophages using liposomal clodronate prevented the development of NASH in mice suggesting that Kupffer cells are critical for the orchestration of inflammation during experimental NASH. Increased understanding of these dynamics may allow us to target potentially harmful populations whilst promoting anti-inflammatory or restorative populations to ultimately guide the development of effective treatment strategies. PMID:27454866

  10. Prohibitin-induced, obesity-associated insulin resistance and accompanying low-grade inflammation causes NASH and HCC

    PubMed Central

    Ande, Sudharsana R.; Nguyen, K. Hoa; Grégoire Nyomba, B. L.; Mishra, Suresh

    2016-01-01

    Obesity increases the risk for nonalcoholic steatohepatitis (NASH) and hepatocarcinogenesis. However, the underlying mechanisms involved in the disease process remain unclear. Recently, we have developed a transgenic obese mouse model (Mito-Ob) by prohibitin mediated mitochondrial remodeling in adipocytes. The Mito-Ob mice develop obesity in a sex-neutral manner, but obesity-associated adipose inflammation and metabolic dysregulation in a male sex-specific manner. Here we report that with aging, the male Mito-Ob mice spontaneously develop obesity-linked NASH and hepatocellular carcinoma (HCC). In contrast, the female Mito-Ob mice maintained normal glucose and insulin levels and did not develop NASH and HCC. The anti-inflammatory peptide ghrelin was significantly upregulated in the female mice and down regulated in the male mice compared with respective control mice. In addition, a reduction in the markers of mitochondrial content and function was found in the liver of male Mito-Ob mice with NASH/HCC development. We found that ERK1/2 signaling was significantly upregulated whereas STAT3 signaling was significantly down regulated in the tumors from Mito-Ob mice. These data provide a proof-of-concept that the metabolic and inflammatory status of the adipose tissue and their interplay at the systemic and hepatic level play a central role in the pathogenesis of obesity-linked NASH and HCC. PMID:27005704

  11. Spontaneous Time Symmetry Breaking in System with Mixed Strategy Nash Equilibrium: Evidences in Experimental Economics Data

    NASA Astrophysics Data System (ADS)

    Wang, Zhijian; Xu, Bin; Zhejiang Collaboration

    2011-03-01

    In social science, laboratory experiment with human subjects' interaction is a standard test-bed for studying social processes in micro level. Usually, as in physics, the processes near equilibrium are suggested as stochastic processes with time-reversal symmetry (TRS). To the best of our knowledge, near equilibrium, the breaking time symmetry, as well as the existence of robust time anti-symmetry processes, has not been reported clearly in experimental economics till now. By employing Markov transition method to analysis the data from human subject 2x2 Games with wide parameters and mixed Nash equilibrium, we study the time symmetry of the social interaction process near Nash equilibrium. We find that, the time symmetry is broken, and there exists a robust time anti-symmetry processes. We also report the weight of the time anti-symmetry processes in the total processes of each the games. Evidences in laboratory marketing experiments, at the same time, are provided as one-dimension cases. In these cases, time anti-symmetry cycles can also be captured. The proposition of time anti-symmetry processes is small, but the cycles are distinguishable.

  12. Animal Models Correlating Immune Cells for the Development of NAFLD/NASH.

    PubMed

    Iyer, Srikanth; Upadhyay, Pramod Kumar; Majumdar, Subeer S; Nagarajan, Perumal

    2015-09-01

    This review mainly elaborates on the animal models available for understanding the pathogenesis of the second hit of non-alcoholic fatty liver disease (NAFLD) involving immune system. This is known to be a step forward from simple steatosis caused during the first hit, which leads to the stage of inflammation followed by more serious liver conditions like non-alcoholic steatohepatitis (NASH) and cirrhosis. Immune-deficient animal models serve as an important tool for understanding the role of a specific cell type or a cytokine in the progression of NAFLD. These animal models can be used in combination with the already available animal models of NAFLD, including dietary models, as well as genetically modified mouse models. Advancements in molecular biological techniques enabled researchers to produce several new animal models for the study of NAFLD, including knockin, generalized knockout, and tissue-specific knockout mice. Development of NASH/NAFLD in various animal models having compromised immune system is discussed in this review. PMID:26628841

  13. P(URI)fying Novel Drivers of NASH and HCC: A Feedforward Loop of IL17A via White Adipose Tissue.

    PubMed

    Weber, Achim; Heikenwalder, Mathias

    2016-07-11

    How obesity and metabolic syndrome trigger non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC) remains elusive. In this issue, Gomes and colleagues describe that nutrient surplus induces hepatic URI expression, triggering genotoxicity and IL17A expression, thus leading to insulin resistance, NASH, and HCC. IL17A signaling blockers might become a readily translatable therapy. PMID:27411585

  14. Evolution of the Distribution of Wealth in an Economic Environment Driven by Local Nash Equilibria

    NASA Astrophysics Data System (ADS)

    Degond, Pierre; Liu, Jian-Guo; Ringhofer, Christian

    2014-02-01

    We present and analyze a model for the evolution of the wealth distribution within a heterogeneous economic environment. The model considers a system of rational agents interacting in a game theoretical framework, through fairly general assumptions on the cost function. This evolution drives the dynamic of the agents in both wealth and economic configuration variables. We consider a regime of scale separation where the large scale dynamics is given by a hydrodynamic closure with a Nash equilibrium serving as the local thermodynamic equilibrium. The result is a system of gas dynamics-type equations for the density and average wealth of the agents on large scales. We recover the inverse gamma distribution as an equilibrium in the particular case of quadratic cost functions which has been previously considered in the literature.

  15. On the Fair Division of Multiple Stochastic Pies to Multiple Agents within the Nash Bargaining Solution

    PubMed Central

    Karmperis, Athanasios C.; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios

    2012-01-01

    The fair division of a surplus is one of the most widely examined problems. This paper focuses on bargaining problems with fixed disagreement payoffs where risk-neutral agents have reached an agreement that is the Nash-bargaining solution (NBS). We consider a stochastic environment, in which the overall return consists of multiple pies with uncertain sizes and we examine how these pies can be allocated with fairness among agents. Specifically, fairness is based on the Aristotle’s maxim: “equals should be treated equally and unequals unequally, in proportion to the relevant inequality”. In this context, fairness is achieved when all the individual stochastic surplus shares which are allocated to agents are distributed in proportion to the NBS. We introduce a novel algorithm, which can be used to compute the ratio of each pie that should be allocated to each agent, in order to ensure fairness within a symmetric or asymmetric NBS. PMID:23024752

  16. Chlamydia psittaci genotype B in a pigeon (Columba livia) inhabiting a public place in San José, Costa Rica

    PubMed Central

    Dolz, G.; Solórzano-Morales, Á.; Angelova, L.; Tien, C.; Fonseca, L.; Bonilla, M.C.

    2013-01-01

    Human chlamydiosis is a zoonotic disease of avian origin caused by Chlamydia psittaci. The highest infection rates have been detected in parrots (Psittacidae) and pigeons (Columbiformes), the latter most frequently carry the genotypes B and E. These genotypes have been shown to also infect humans. Because pigeons (Columba livia) cohabit with humans in urban areas, C. psittaci present in the dust from dry feces of infected pigeons may be transmitted by inhalation and represent a significant public health problem. Between 2012 and 2013 a total of 120 fecal samples were collected from pigeons at four public places (Plaza de la Cultura, Parque Morazán, Parque Central de Guadalupe, Plaza de las Garantías Sociales) in San José, Costa Rica. A nested polymerase chain reaction (PCR) was used to amplify a region of the outer membrane protein A gene of C. psittaci. Only one sample was positive in PCR and the positive sample was further subjected to sequencing and genotyping. Sequencing identified this sample as C. psittaci genotype B. This study is the first report to show the presence of this organism in pigeons of Costa Rica, and shows that the infected pigeons may represent a significant risk for humans who visit public places that are inhabited by pigeons. PMID:26623327

  17. Heterotopic implantation of autologous bone marrow in rock pigeons (Columba livia): possible applications in avian bone grafting.

    PubMed

    Sanaei, M Reza; Abu, Jalila; Nazari, Mojgan; Faiz, Nik Mohd; Bakar, Mohd Zuki Abu; Allaudin, Zeenathul N

    2011-12-01

    Autologous bone marrow, alone or as a composite marrow graft, has received much attention in various species. To assess the potential osteogenicity of autologous, extramedullary bone marrow implants in an avian model, 24 adult pigeons (Columba livia) were given intramuscular implantations of autologous marrow aspirated from the medial tibiotarsus. Birds were euthanatized at 1, 4, 6, 8, 10, and 12 weeks after surgery to evaluate whether ectopic bone had formed at the implant sites. Primary evaluations by in situ radiography and postmortem histologic examinations showed no evidence of bone formation. Further evaluation with histologic scores and histomorphometry revealed a significantly increased rate of angiogenesis at the implant sites by the sixth and tenth week postimplantation (P < .05). No significant differences between the treatment and control sites were present at any other endpoints. Results of this study show that, although autologous bone marrow lacks heterotopic osteogenic potentials in this avian model, it could still function as a useful adjunct to routine bone grafting techniques because of its unique capabilities to promote early angiogenesis. PMID:22458179

  18. Who are the real bird brains? Qualitative differences in behavioral flexibility between dogs (Canis familiaris) and pigeons (Columba livia).

    PubMed

    Laude, Jennifer R; Pattison, Kristina F; Rayburn-Reeves, Rebecca M; Michler, Daniel M; Zentall, Thomas R

    2016-01-01

    Pigeons given a simultaneous spatial discrimination reversal, in which a single reversal occurs at the midpoint of each session, consistently show anticipation prior to the reversal as well as perseveration after the reversal, suggesting that they use a less effective cue (time or trial number into the session) than what would be optimal to maximize reinforcement (local feedback from the most recent trials). In contrast, rats (Rattus norvegicus) and humans show near-optimal reversal learning on this task. To determine whether this is a general characteristic of mammals, in the present research, pigeons (Columba livia) and dogs (Canis familiaris) were tested with a simultaneous spatial discrimination mid-session reversal. Overall, dogs performed the task more poorly than pigeons. Interestingly, both pigeons and dogs employed what resembled a timing strategy. However, dogs showed greater perseverative errors, suggesting that they may have relatively poorer working memory and inhibitory control with this task. The greater efficiency shown by pigeons with this task suggests they are better able to time and use the feedback from their preceding choice as the basis of their future choice, highlighting what may be a qualitative difference between the species. PMID:26364290

  19. Chlamydia psittaci genotype B in a pigeon (Columba livia) inhabiting a public place in San José, Costa Rica.

    PubMed

    Dolz, G; Solórzano-Morales, Á; Angelova, L; Tien, C; Fonseca, L; Bonilla, M C

    2013-01-01

    Human chlamydiosis is a zoonotic disease of avian origin caused by Chlamydia psittaci. The highest infection rates have been detected in parrots (Psittacidae) and pigeons (Columbiformes), the latter most frequently carry the genotypes B and E. These genotypes have been shown to also infect humans. Because pigeons (Columba livia) cohabit with humans in urban areas, C. psittaci present in the dust from dry feces of infected pigeons may be transmitted by inhalation and represent a significant public health problem. Between 2012 and 2013 a total of 120 fecal samples were collected from pigeons at four public places (Plaza de la Cultura, Parque Morazán, Parque Central de Guadalupe, Plaza de las Garantías Sociales) in San José, Costa Rica. A nested polymerase chain reaction (PCR) was used to amplify a region of the outer membrane protein A gene of C. psittaci. Only one sample was positive in PCR and the positive sample was further subjected to sequencing and genotyping. Sequencing identified this sample as C. psittaci genotype B. This study is the first report to show the presence of this organism in pigeons of Costa Rica, and shows that the infected pigeons may represent a significant risk for humans who visit public places that are inhabited by pigeons. PMID:26623327

  20. The effect of alpha2-adrenergic receptors on cutaneous water evaporation in the rock pigeon (Columba livia).

    PubMed

    Ophir, Eshel; Arieli, Yehuda; Marder, Jacob

    2004-12-01

    The role of beta-adrenergic receptors in regulating cutaneous water evaporation (CWE) in the rock pigeon (Columba livia) is well documented. Here, we studied the involvement of the alpha2-adrenergic receptors in this cooling mechanism of the heat-acclimated (HAc) pigeon. Systemic alpha2-adrenergic activation [clonidine, 50 microg kg(-1), intramuscular (i.m.)] was found to increase CWE in heat-acclimated pigeons at an ambient temperature (T(a)) of 25 degrees C. Subcutaneous administration of the drug had no significant effect. Preinjection of an alpha2-adrenergic antagonist (yohimbine, 10 mg kg(-1), i.m.) completely prevented clonidine-induced CWE and attenuated propranolol-induced CWE by 53%. Pretreatment with a beta-adrenergic agonist (isoproterenol, 4 mg kg(-1), i.m.) abolished the effect of clonidine. None of the above treatments was found to elicit significant CWE in nonacclimated (NAc) pigeons. These findings, in addition to previously reported data, indicate a complex regulatory pathway of CWE in the heat-acclimated pigeon consisting of alpha2- and beta2-adrenergic receptors. The possible hierarchical pattern of these receptors is discussed. PMID:15596385

  1. Quantitative ultrasound, magnetic resonance imaging, and histologic image analysis of hepatic iron accumulation in pigeons (Columbia livia).

    PubMed

    Matheson, Jodi S; Paul-Murphy, Joanne; O'Brien, Robert T; Steinberg, Howard

    2007-06-01

    Iron overload was induced by iron dextran i.v. in clinically healthy adult pigeons, Columbia livia, (n = 8). Hemosiderosis was induced in all treated birds. Two control pigeons received no iron injections. Pigeons did not show clinical signs of iron overload during the 6-wk study. Ultrasound examination of the liver in the pigeons receiving iron dextran was performed on days 0, 13, 28, and 42. No ultrasound images were collected on the control pigeons. Magnetic resonance imaging was performed on days 0, 13, 28, and 42 on all study pigeons and imaging sequences were collected in three different imaging formats: T1, T2, and gradient-recalled echo (GRE). Surgical liver biopsies were performed on pigeons receiving iron dextran on days 2, 16, and 45 (at necropsy). A single liver sample was collected at necropsy from the control birds. Histologic examination, quantitative image analysis, and tissue iron analysis by thin-layer chromatography were performed on each liver sample and compared to the imaging studies. Although hemosiderosis was confirmed histologically in each experimental pigeon, no significant change in pixel intensity of the ultrasound images was seen at any point in the study. Signal intensity, in all magnetic resonance imaging formats, significantly decreased in a linear fashion as the accumulation of iron increased. PMID:17679505

  2. Protective effect of salvianolic acid B on NASH rat liver through restoring intestinal mucosal barrier function

    PubMed Central

    Wang, Ying-Chun; Jin, Qing-Mei; Kong, Wei-Zong; Chen, Juan

    2015-01-01

    Aim: To investigate the effect of Salvianolic acid B (Sal B) on the disease progress of NASH and change of intestinal barrier function. Methods: Sixty Sprague-Dawley (SD) rats were randomly divided into control group, model group and treated group, with the former given normal diet and the latter 2 groups rats fed high-fat diet. In treated group, rats were infused through the stomach with 1 mg/ml Sal B every day at a dose of 20 mL/kg body weight. All animals were killed at the 24th week and plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC), endotoxin (ET) and diamine oxdase (DAO) were analyzed using the blood samples. The histopathology of liver was observed by H&E staining. The expression changes of tight junction protein occludin and ZO-1 were analyzed by immunocytochemistry. Ultrastructural morphology of small intestinal tissues was investigated by transmission electron microscopy. Results: Plasma levels of ALT, AST, TG, TC, ET and DAO were significantly higher in model group than those in both control group and group treated with Sal B. In model group, vacuolated swelling of the cytoplasm with aggregates of chronic inflammatory cells was observed in the liver tissue but not in Sal B-treated group. NAFLD Activity Score in the treated group was significantly lower than that in model group. Immunohistochemical staining showed that Sal B administration recovered the expression of occludin and ZO-1, which was downregulated in the model group. Transmission electron microscopy analysis demonstrated that cell surface microvilli and major intercellular junctional complex including tight junction, gap junction and adherens junction were restored in Sal B-treated group. Conclusion: Sal B exerted protective function against high-fat diet-induced liver damage by restoring healthy barrier function of intestine in NASH rat model. PMID:26191218

  3. NAFLD and NASH in HCV Infection: Prevalence and Significance in Hepatic and Extrahepatic Manifestations.

    PubMed

    Adinolfi, Luigi Elio; Rinaldi, Luca; Guerrera, Barbara; Restivo, Luciano; Marrone, Aldo; Giordano, Mauro; Zampino, Rosa

    2016-01-01

    The aim of this paper is to review and up to date the prevalence of hepatitis C virus (HCV)-associated non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) and their significance in both accelerating progression of HCV-related liver disease and development of HCV-associated extrahepatic diseases. The reported mean prevalence of HCV-related NAFLD was 55%, whereas NASH was reported in 4%-10% of cases. HCV genotype 3 directly induces fatty liver deposition, namely "viral steatosis" and it is associated with the highest prevalence and degree of severity, whereas, HCV non-3 genotype infection showed lower prevalence of steatosis, which is associated with metabolic factors and insulin resistance. The host's genetic background predisposes him or her to the development of steatosis. HCV's impairment of lipid and glucose metabolism causes fatty liver accumulation; this seems to be a viral strategy to optimize its life cycle. Irrespective of insulin resistance, HCV-associated NAFLD, in a degree-dependent manner, contributes towards accelerating the liver fibrosis progression and development of hepatocellular carcinoma by inducing liver inflammation and oxidative stress. Furthermore, NAFLD is associated with the presence of metabolic syndrome, type 2 diabetes, and atherosclerosis. In addition, HCV-related "metabolic steatosis" impairs the response rate to interferon-based treatment, whereas it seems that "viral steatosis" may harm the response rate to new oral direct antiviral agents. In conclusion, a high prevalence of NAFLD occurs in HCV infections, which is, at least in part, induced by the virus, and that NAFLD significantly impacts progression of the liver disease, therapeutic response, and some extrahepatic diseases. PMID:27231906

  4. Supplementation of sodium butyrate protects mice from the development of non-alcoholic steatohepatitis (NASH).

    PubMed

    Jin, Cheng Jun; Sellmann, Cathrin; Engstler, Anna Janina; Ziegenhardt, Doreen; Bergheim, Ina

    2015-12-14

    Overnutrition, insulin resistance and an impaired intestinal barrier function are discussed as critical factors in the development of non-alcoholic fatty liver disease. Not only butyrate-producing probiotics as well as supplementation of sodium butyrate (SoB) have been suggested to bear protective effects on liver damage of various aetiologies. However, whether an oral consumption of SoB has a protective effect on Western-style diet (WSD)-induced non-alcoholic steatohepatitis (NASH) and if so molecular mechanism involved has not yet been determined. Eight-week-old C57BL/6J mice were pair-fed either a liquid control or WSD±0·6 g/kg body weight SoB. After 6 weeks, markers of liver damage, inflammation, toll-like receptor (TLR)-4 signalling, lipid peroxidation and glucose as well as lipid metabolism were determined in the liver tissue. Tight junction protein levels were determined in the duodenal tissue. SoB supplementation had no effects on the body weight gain or liver weight of WSD-fed mice, whereas liver steatosis and hepatic inflammation were significantly decreased (e.g. less inflammatory foci and neutrophils) when compared with mice fed only a WSD. Tight junction protein levels in duodenum, hepatic mRNA expression of TLR-4 and sterol regulatory element-binding protein 1c were altered similarly in both WSD groups when compared with controls, whereas protein levels of myeloid differentiation primary response gene 88, inducible nitric oxide synthase, 4-hydroxynonenal protein adducts and F4/80 macrophages were only significantly induced in livers of mice fed only the WSD. In summary, these data suggest that an oral supplementation of SoB protects mice from inflammation in the liver and thus from the development of WSD-induced NASH. PMID:26450277

  5. Midkine Increases Diagnostic Yield in AFP Negative and NASH-Related Hepatocellular Carcinoma

    PubMed Central

    Vongsuvanh, Roslyn; van der Poorten, David; Iseli, Tristan; Strasser, Simone I.; McCaughan, Geoffrey W.; George, Jacob

    2016-01-01

    Robust biomarkers for population-level hepatocellular carcinoma (HCC) surveillance are lacking. We compared serum midkine (MDK), dickkopf-1 (DKK1), osteopontin (OPN) and AFP for HCC diagnosis in 86 HCC patients matched to 86 cirrhotics, 86 with chronic liver disease (CLD) and 86 healthy controls (HC). Based on the performance of each biomarker, we assessed a separate longitudinal cohort of 28 HCC patients, at and before cancer diagnosis. Serum levels of MDK and OPN were higher in HCC patients compared to cirrhosis, CLD and HC groups. DKK1 was not different between cases and controls. More than half of HCC patients had normal AFP. In this AFP-negative HCC cohort, 59.18% (n = 29/49) had elevated MDK, applying the optimal cut-off of 0.44 ng/ml. Using AFP ≥ 20 IU/ml or MDK ≥ 0.44 ng/ml, a significantly greater number (76.7%; n = 66/86) of HCC cases were detected. The area under the receiver operating curve for MDK was superior to AFP and OPN in NASH-HCC diagnosis. In the longitudinal cohort, MDK was elevated in 15/28 (54%) of HCC patients at diagnosis, of whom 67% had elevated MDK 6 months prior. Conclusion: AFP and MDK have a complementary role in HCC detection. MDK increases the diagnostic yield in AFP-negative HCC and has greater diagnostic performance than AFP, OPN and DKK-1 in the diagnosis of NASH-HCC. Additionally, MDK has a promising role in the pre-clinical diagnosis of HCC. PMID:27219517

  6. DSS colitis promotes tumorigenesis and fibrogenesis in a choline-deficient high-fat diet-induced NASH mouse model.

    PubMed

    Achiwa, Koichi; Ishigami, Masatoshi; Ishizu, Yoji; Kuzuya, Teiji; Honda, Takashi; Hayashi, Kazuhiko; Hirooka, Yoshiki; Katano, Yoshiaki; Goto, Hidemi

    2016-01-29

    Nonalcoholic steatohepatitis (NASH) patients progress to liver cirrhosis and even hepatocellular carcinoma (HCC). Several lines of evidence indicate that accumulation of lipopolysaccharide (LPS) and disruption of gut microbiota play contributory roles in HCC. Moreover, in a dextran sodium sulfate (DSS)-induced colitis model in mice, a high-fat diet increases portal LPS level and promotes hepatic inflammation and fibrosis. However, this diet-induced NASH model requires at least 50 weeks for carcinogenesis. In this study, we sought to determine whether increased intestinal permeability would aggravate liver inflammation and fibrosis and accelerate tumorigenesis in a diet-induced NASH model. Mice were fed a choline-deficient high-fat (CDHF) diet for 4 or 12 weeks. The DSS group was fed CDHF and intermittently received 1% DSS in the drinking water. Exposure to DSS promoted mucosal changes such as crypt loss and increased the number of inflammatory cells in the colon. In the DSS group, portal LPS levels were elevated at 4 weeks, and the proportions of Clostridium cluster XI in the fecal microbiota were elevated. In addition, levels of serum transaminase, number of lobular inflammatory cells, F4/80 staining-positive area, and levels of inflammatory cytokines were all elevated in the DSS group. Liver histology in the DSS group revealed severe fibrosis at 12 weeks. Liver tumors were detected in the DSS group at 12 weeks, but not in the other groups. Thus, DSS administration promoted liver tumors in a CDHF diet-induced NASH mouse over the short term, suggesting that the induction of intestinal inflammation and gut disruption of microbiota in NASH promote hepatic tumorigenesis. PMID:26682925

  7. Oral Nitrate Reductase Activity Is Not Associated with Development of Non-Alcoholic Fatty Liver Disease (NAFLD) and Non-Alcoholic Steatohepatitis (NASH): A Pilot Study

    PubMed Central

    Barzin, Gilda; Merat, Shahin; Nokhbeh-Zaeem, Habibeh; Saniee, Parastoo; Pedramnia, Shahrzad; Mostashfi Habibabadi, Ali; Nasseri-Moghaddam, Siavosh

    2014-01-01

    BACKGROUND NAFLD/NASH is a manifestation of metabolic syndrome and is associated with obesity/overweight. Not all obese/overweight individuals develop NASH. Gastro-esophageal reflux disease (GERD) is considered a gastrointestinal manifestation of the metabolic syndrome and is associated with obesity/overweight. Again not all obese/overweight individuals develop GERD. Recent data show association of dietary nitrate content and oral nitrate reductase activity (NRA) with GERD. Nitrates need to be converted to nitrite (done in human beings by nitrate reductase of oral bacteria exclusively) to be active in metabolic pathways. OBJECTIVE To assess the relation between NASH/NAFLD and oral NRA. METHODS Oral NRA was measured in individuals with NASH (compatible abdominal ultrasound and two elevated ALT/AST levels over six months) and was compared with that of those without NASH. Oral NRA was measured according to a previously reported protocol. RESULTS Eleven NASH patients and twelve controls were enrolled. Mean oral NRA activity were 2.82 vs. 3.51 μg nitrite-N formed per person per minute for cases and controls respectively (p=0.46). CONCLUSION According to our data, oral nitrite production is not different between individual swith and without NASH. PMID:24829701

  8. Histologic Evaluation of Critical Size Defect Healing With Natural and Synthetic Bone Grafts in the Pigeon ( Columba livia ) Ulna.

    PubMed

    Tunio, Ahmed; Jalila, Abu; Goh, Yong Meng; Shameha-Intan; Shanthi, Ganabadi

    2015-06-01

    Fracture and bone segment loss are major clinical problems in birds. Achieving bone formation and clinical union in a fracture case is important for the survival of the bird. To evaluate the efficacy of bone grafts for defect healing in birds, 2 different bone grafts were investigated in the healing of a bone defect in 24 healthy pigeons ( Columba livia ). In each bird, a 1-cm critical size defect (CSD) was created in the left ulna, and the fracture was stabilized with external skeletal fixation (ESF). A graft of hydroxyapatite (HA) alone (n = 12 birds) or demineralized bone matrix (DBM) combined with HA (n = 12 birds) was implanted in the CSD. The CSD healing was evaluated at 3 endpoints: 3, 6, and 12 weeks after surgery. Four birds were euthanatized at each endpoint from each treatment group, and bone graft healing in the ulna CSD was evaluated by histologic examination. The CSD and graft implants were evaluated for quality of union, cortex development, and bone graft incorporation. Results showed no graft rejection in any bird, and all birds had connective tissue formation in the defect because of the bone graft application. These results suggest that bone defect healing can be achieved by a combination of osteoinductive and osteoconductive bone graft materials for clinical union and new bone regeneration in birds. The combination of DBM and HA resulted in a better quality bone graft (P < .05) than did HA alone, but there was no significant differences in cortex development or bone graft incorporation at 3, 6, or 12 weeks. From the results of this study, we conclude that HA bone grafts, alone or in combination with DBM, with external skeletal fixation is suitable and safe for bone defect and fracture treatment in pigeons. PMID:26115209

  9. Trace metals, melanin-based pigmentation and their interaction influence immune parameters in feral pigeons (Columba livia).

    PubMed

    Chatelain, M; Gasparini, J; Frantz, A

    2016-04-01

    Understanding the effects of trace metals emitted by anthropogenic activities on wildlife is of great concern in urban ecology; yet, information on how they affect individuals, populations, communities and ecosystems remains scarce. In particular, trace metals may impact survival by altering the immune system response to parasites. Plumage melanin is assumed to influence the effects of trace metals on immunity owing to its ability to bind metal ions in feathers and its synthesis being coded by a pleiotropic gene. We thus hypothesized that trace metal exposure would interact with plumage colouration in shaping immune response. We experimentally investigated the interactive effect between exposure to an environmentally relevant range of zinc and/or lead and melanin-based plumage colouration on components of the immune system in feral pigeons (Columba livia). We found that zinc increased anti-keyhole limpet hemocyanin (KLH) IgY primary response maintenance, buffered the negative effect of lead on anti-KLH IgY secondary response maintenance and tended to increase T-cell mediated phytohaemagglutinin (PHA) skin response. Lead decreased the peak of the anti-KLH IgY secondary response. In addition, pheomelanic pigeons exhibited a higher secondary anti-KLH IgY response than did eumelanic ones. Finally, T-cell mediated PHA skin response decreased with increasing plumage eumelanin level of birds exposed to lead. Neither treatments nor plumage colouration correlated with endoparasite intensity. Overall, our study points out the effects of trace metals on some parameters of birds' immunity, independently from other confounding urbanization factors, and underlines the need to investigate their impacts on other life history traits and their consequences in the ecology and evolution of host-parasite interactions. PMID:26809976

  10. Parasite distribution and early-stage encephalitis in Sarcocystis calchasi infections in domestic pigeons (Columba livia f. domestica).

    PubMed

    Maier, Kristina; Olias, Philipp; Enderlein, Dirk; Klopfleisch, Robert; Mayr, Sylvia L; Gruber, Achim D; Lierz, Michael

    2015-01-01

    Pigeon protozoal encephalitis is a biphasic, neurologic disease of domestic pigeons (Columba livia f. domestica) caused by the apicomplexan parasite Sarcocystis calchasi. Despite severe inflammatory lesions of the brain, associated parasitic stages have only rarely been identified and the cause of the lesions is still unclear. The aim of this study was therefore to characterize the tissue distribution of S. calchasi within pigeons between the two clinical phases and during the occurrence of neurological signs. For this purpose, a semi-quantitative real-time polymerase chain reaction (PCR) was developed. Forty-five domestic pigeons were infected orally (via a cannula into the crop) with 200 S. calchasi sporocysts and euthanized in groups of three pigeons at intervals of 2 to 10 days over a period of 61 days. Tissue samples including brain and skeletal muscle were examined by histology, immunohistochemistry, and PCR. Schizonts were detected in the liver of one pigeon at day 10 post infection. A mild encephalitis was detected at day 20 post infection, around 4 weeks before the onset of neurological signs. At the same time, immature sarcocysts were present in the skeletal muscle. In seven pigeons a few sarcocysts were identified in the brain, but not associated with any lesion. These results suggest that the encephalitis is induced at a very early stage of the S. calchasi lifecycle rather than in the chronic phase of pigeon protozoal encephalitis. Despite the increasing severity of lesions in the central nervous system, the amount of sarcocysts did not increase. This supports the hypothesis of a delayed-type hypersensitivity response as the cause of the encephalitis. The study also demonstrated that S. calchasi DNA is detectable in tissues negative by histological methods, indicating a higher sensitivity of the real-time PCR. PMID:25338141

  11.  Monozygotic twins with NASH cirrhosis: cumulative effect of multiple single nucleotide polymorphisms?

    PubMed

    Grove, Jane I; Austin, Mark; Tibble, Jeremy; Aithal, Guruprasad P; Verma, Sumita

    2016-01-01

     Multiple genetic and environmental factors interact to determine an individual's predisposition to non-alcoholic fatty liver disease and its phenotypic characteristics. Association studies have found a number of alleles associated with the development of non-alcoholic steatohepatitis. Our aim was to investigate whether multiple risk-associated alleles may be present in affected monozygotic twins, indicating underlying genetic predisposition to non-alcoholic steatohepatitis. We determined the genotype of 14 candidate gene polymorphisms (at 11 unlinked loci) in a set of monozygotic twins who presented with cirrhosis within 18 months of each other. Genotyping revealed multiple single nucleotide polymorphisms at 9 independent loci in genes PNPLA3, APOC3, GCKR, TRIB1, LYPLAL1, PPP1R3B, COL13A1, and EFCAB4B, previously implicated in contributing to non-alcoholic steatohepatitis pathogenesis. In conclusion, this case series illustrates the potential cumulative effect of multiple polymorphisms in the development and potential progression of a complex trait such as NASH cirrhosis. PMID:26845607

  12. Evolution of wealth in a non-conservative economy driven by local Nash equilibria

    PubMed Central

    Degond, Pierre; Liu, Jian-Guo; Ringhofer, Christian

    2014-01-01

    We develop a model for the evolution of wealth in a non-conservative economic environment, extending a theory developed in Degond et al. (2014 J. Stat. Phys. 154, 751–780 (doi:10.1007/s10955-013-0888-4)). The model considers a system of rational agents interacting in a game-theoretical framework. This evolution drives the dynamics of the agents in both wealth and economic configuration variables. The cost function is chosen to represent a risk-averse strategy of each agent. That is, the agent is more likely to interact with the market, the more predictable the market, and therefore the smaller its individual risk. This yields a kinetic equation for an effective single particle agent density with a Nash equilibrium serving as the local thermodynamic equilibrium. We consider a regime of scale separation where the large-scale dynamics is given by a hydrodynamic closure with this local equilibrium. A class of generalized collision invariants is developed to overcome the difficulty of the non-conservative property in the hydrodynamic closure derivation of the large-scale dynamics for the evolution of wealth distribution. The result is a system of gas dynamics-type equations for the density and average wealth of the agents on large scales. We recover the inverse Gamma distribution, which has been previously considered in the literature, as a local equilibrium for particular choices of the cost function. PMID:25288808

  13. A Differential Evolution Algorithm Based on Nikaido-Isoda Function for Solving Nash Equilibrium in Nonlinear Continuous Games.

    PubMed

    He, Feng; Zhang, Wei; Zhang, Guoqiang

    2016-01-01

    A differential evolution algorithm for solving Nash equilibrium in nonlinear continuous games is presented in this paper, called NIDE (Nikaido-Isoda differential evolution). At each generation, parent and child strategy profiles are compared one by one pairwisely, adapting Nikaido-Isoda function as fitness function. In practice, the NE of nonlinear game model with cubic cost function and quadratic demand function is solved, and this method could also be applied to non-concave payoff functions. Moreover, the NIDE is compared with the existing Nash Domination Evolutionary Multiplayer Optimization (NDEMO), the result showed that NIDE was significantly better than NDEMO with less iterations and shorter running time. These numerical examples suggested that the NIDE method is potentially useful. PMID:27589229

  14. Nonalcoholic steatohepatitic (NASH) mice are protected from higher hepatotoxicity of acetaminophen upon induction of PPAR{alpha} with clofibrate

    SciTech Connect

    Donthamsetty, Shashikiran; Bhave, Vishakha S.; Mitra, Mayurranjan S.; Latendresse, John R.; Mehendale, Harihara M.

    2008-08-01

    The objective was to investigate if the hepatotoxic sensitivity in nonalcoholic steatohepatitic mice to acetaminophen (APAP) is due to downregulation of nuclear receptor PPAR{alpha} via lower cell division and tissue repair. Male Swiss Webster mice fed methionine and choline deficient diet for 31 days exhibited NASH. On the 32nd day, a marginally toxic dose of APAP (360 mg/kg, ip) yielded 70% mortality in steatohepatitic mice, while all non steatohepatitic mice receiving the same dose survived. {sup 14}C-APAP covalent binding, CYP2E1 protein, and enzyme activity did not differ from the controls, obviating increased APAP bioactivation as the cause of amplified APAP hepatotoxicity. Liver injury progressed only in steatohepatitic livers between 6 and 24 h. Cell division and tissue repair assessed by {sup 3}H-thymidine incorporation and PCNA were inhibited only in the steatohepatitic mice given APAP suggesting that higher sensitivity of NASH liver to APAP-induced hepatotoxicity was due to lower tissue repair. The hypothesis that impeded liver tissue repair in steatohepatitic mice was due to downregulation of PPAR{alpha} was tested. PPAR{alpha} was downregulated in NASH. To investigate whether downregulation of PPAR{alpha} in NASH is the critical mechanism of compromised liver tissue repair, PPAR{alpha} was induced in steatohepatitic mice with clofibrate (250 mg/kg for 3 days, ip) before injecting APAP. All clofibrate pretreated steatohepatitic mice receiving APAP exhibited lower liver injury, which did not progress and the mice survived. The protection was not due to lower bioactivation of APAP but due to higher liver tissue repair. These findings suggest that inadequate PPAR{alpha} expression in steatohepatitic mice sensitizes them to APAP hepatotoxicity.

  15. Hepatic Expression Patterns of Inflammatory and Immune Response Genes Associated with Obesity and NASH in Morbidly Obese Patients

    PubMed Central

    Bertola, Adeline; Bonnafous, Stéphanie; Anty, Rodolphe; Patouraux, Stéphanie; Saint-Paul, Marie-Christine; Iannelli, Antonio; Gugenheim, Jean; Barr, Jonathan; Mato, José M.; Le Marchand-Brustel, Yannick; Tran, Albert; Gual, Philippe

    2010-01-01

    Background Obesity modulates inflammation and activation of immune pathways which can lead to liver complications. We aimed at identifying expression patterns of inflammatory and immune response genes specifically associated with obesity and NASH in the liver of morbidly obese patients. Methodology/Principal Findings Expression of 222 genes was evaluated by quantitative RT-PCR in the liver of morbidly obese patients with histologically normal liver (n = 6), or with severe steatosis without (n = 6) or with NASH (n = 6), and in lean controls (n = 5). Hepatic expression of 58 out of 222 inflammatory and immune response genes was upregulated in NASH patients. The most notable changes occurred in genes encoding chemokines and chemokine receptors involved in leukocyte recruitment, CD and cytokines involved in the T cell activation towards a Th1 phenotype, and immune semaphorins. This regulation seems to be specific for the liver since visceral adipose tissue expression and serum levels of MCP1, IP10, TNFα and IL6 were not modified. Importantly, 47 other genes were already upregulated in histologically normal liver (e.g. CRP, Toll-like receptor (TLR) pathway). Interestingly, serum palmitate, known to activate the TLR pathway, was increased with steatosis. Conclusion/Significance The liver of obese patients without histological abnormalities already displayed a low-grade inflammation and could be more responsive to activators of the TLR pathway. NASH was then characterized by a specific gene signature. These findings help to identify new potential actors of the pathogenesis of NAFLD. PMID:21042596

  16. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, NM

    SciTech Connect

    Murphy, Mark B.

    1999-02-24

    The Nash Draw Brushy Canyon Pool in Eddy County New Mexico is a cost-shared field demonstration project in the US Department of Energy Class II Program. A major goal of the Class III Program is to stimulate the use of advanced technologies to increase ultimate recovery from slope-basin clastic reservoirs. Advanced characterization techniques are being used at the Nash Draw project to develop reservoir management strategies for optimizing oil recovery from this Delaware reservoir. Analysis, interpretation, and integration of recently acquired geologic, geophysical, and engineering data revealed that the initial reservoir characterization was too simplistic to capture the critical features of this complex formation. Contrary to the initial characterization, a new reservoir description evolved that provided sufficient detail regarding the complexity of the Brushy Canyon interval at Nash Draw. This new reservoir description is being used as a risk reduction tool to identify ''sweet spots'' for a development drilling program as well as to evaluate pressure maintenance strategies. The reservoir characterization, geological modeling, 3-D seismic interpretation, and simulation studies have provided a detailed model of the Brushy Canyon zones. This model was used to predict the success of different reservoir management scenarios and to aid in determining the most favorable combination of targeted drilling, pressure maintenance, well simulation, and well spacing to improve recovery from this reservoir.

  17. Application of game theory on parameter optimization of the novel two-stage Nash nonlinear grey Bernoulli model

    NASA Astrophysics Data System (ADS)

    Hsin, Pei-Han; Chen, Chun-I.

    2015-10-01

    In grey prediction modeling, there are three parameters in nonlinear grey Bernoulli model (NGBM), including the power n, the coefficient p and the length of raw data used to construct grey forecasting model. Nash NGBM only optimizes n and p by the iterated elimination of weakly dominated strategies of game theory. To optimize above three parameters, this study develops a two-stage game for NNGBM (abbreviated as two-stage NNGBM). In the first stage, find the Nash equilibrium for each possible game. In the second stage, use Minimax principle to find the optimal left topological sequence which has the best forecasting performance. Then, obtain Nash equilibrium which consists of these three parameters. This study also proves that the traditional GM(1, 1), optimal p GM(1, 1) and NGBM(1, 1) are the special cases of the proposed model. In order to show the feasibility of this research, the proposed method is applied to the forecasting of Taiwan's GDP. The results show that five elements in raw data sequence are optimal topological length for constructing NNGBM in the case of Taiwan's GDP forecasting.

  18. Growth of embryo and gene expression of nutrient transporters in the small intestine of the domestic pigeon (Columba livia)*

    PubMed Central

    Chen, Ming-xia; Li, Xiang-guang; Yang, Jun-xian; Gao, Chun-qi; Wang, Bin; Wang, Xiu-qi; Yan, Hui-chao

    2015-01-01

    The objective of this study was to investigate the relationship between gene expression of nutrient (amino acid, peptide, sodium and proton) transporters in the small intestine and embryonic growth in domestic pigeons (Columba livia). One hundred and twenty-five fertilized eggs were randomly assigned into five groups and were incubated under optimal conditions (temperature of 38.1 °C and relative humidity of 55%). Twenty embryos/birds from each group were sacrificed by cervical dislocation on embryonic day (E) 9, 11, 13, 15 and day of hatch (DOH). The eggs, embryos (without yolk sac), and organs (head, brain, heart, liver, lungs, kidney, gizzard, small intestine, legs, and thorax) were dissected, cleaned, and weighed. Small intestine samples were collected for RNA isolation. The mRNA abundance of intestinal nutrient transporters was evaluated by real-time reverse transcription-polymerase chain reaction (RT-PCR). We classified these ten organs into four types according to the changes in relative weight during embryonic development. In addition, the gene expression of nutrient transporters was differentially regulated by embryonic day. The mRNA abundances of b0,+AT, EAAT3, y+LAT2, PepT1, LAT4, NHE2, and NHE3 increased linearly with age, whereas mRNA abundances of CAT1, CAT2, LAT1, EAAT2, SNAT1, and SNAT2 were increased to higher levels on E9 or E11 and then decreased to lower levels until DOH. The results of correlation analysis showed that the gene expressions of b0,+AT, EAAT3, PepT1, LAT4, NHE2, NHE3, and y+LAT2 had positive correlations with body weight (0.71

  19. Growth of embryo and gene expression of nutrient transporters in the small intestine of the domestic pigeon (Columba livia).

    PubMed

    Chen, Ming-xia; Li, Xiang-guang; Yang, Jun-xian; Gao, Chun-qi; Wang, Bin; Wang, Xiu-qi; Yan, Hui-chao

    2015-06-01

    The objective of this study was to investigate the relationship between gene expression of nutrient (amino acid, peptide, sodium and proton) transporters in the small intestine and embryonic growth in domestic pigeons (Columba livia). One hundred and twenty-five fertilized eggs were randomly assigned into five groups and were incubated under optimal conditions (temperature of 38.1 °C and relative humidity of 55%). Twenty embryos/birds from each group were sacrificed by cervical dislocation on embryonic day (E) 9, 11, 13, 15 and day of hatch (DOH). The eggs, embryos (without yolk sac), and organs (head, brain, heart, liver, lungs, kidney, gizzard, small intestine, legs, and thorax) were dissected, cleaned, and weighed. Small intestine samples were collected for RNA isolation. The mRNA abundance of intestinal nutrient transporters was evaluated by real-time reverse transcription-polymerase chain reaction (RT-PCR). We classified these ten organs into four types according to the changes in relative weight during embryonic development. In addition, the gene expression of nutrient transporters was differentially regulated by embryonic day. The mRNA abundances of b(0,+)AT, EAAT3, y(+)LAT2, PepT1, LAT4, NHE2, and NHE3 increased linearly with age, whereas mRNA abundances of CAT1, CAT2, LAT1, EAAT2, SNAT1, and SNAT2 were increased to higher levels on E9 or E11 and then decreased to lower levels until DOH. The results of correlation analysis showed that the gene expressions of b(0,+)AT, EAAT3, PepT1, LAT4, NHE2, NHE3, and y(+)LAT2 had positive correlations with body weight (0.71

  20. Investigations into the uricolytic properties of urate oxidase in a granivorous (Columba livia domestica) and in a carnivorous (Buteo jamaicensis) avian species.

    PubMed

    Poffers, J; Lumeij, J T; Redig, P T

    2002-12-01

    To study the uricolytic properties of urate oxidase in granivorous and carnivorous birds, experiments were conducted in pigeons (Columba livia domestica) and Red-tailed Hawks (Buteo jamaicensis). Plasma concentrations of allantoin and uric acid were determined at various times in experimental groups before and after receiving 100, 200, and 600 U/kg urate oxidase once daily and were compared with controls. All regimens caused a significant decrease in plasma uric acid concentrations within 2 days after the first administration, when compared with controls. Furthermore, both doses used in Red-tailed Hawks (200 and 100 U/kg) caused a significant postprandial suppression of plasma uric acid concentrations. Plasma allantoin concentrations were significantly higher when compared with controls. The ability of urate oxidase to prevent the physiological postprandial hyperuricaemia in Red-tailed Hawks and to reduce plasma uric acid concentrations to undetectable levels, shows the great potential of this drug for treating avian hyperuricaemia. PMID:12593740

  1. Experimental infection of rock pigeons (Columba livia) with three West Nile virus lineage 1 strains isolated in Italy between 2009 and 2012.

    PubMed

    Spedicato, M; Carmine, I; Bellacicco, A L; Marruchella, G; Marini, V; Pisciella, M; Di Francesco, G; Lorusso, A; Monaco, F; Savini, G

    2016-04-01

    West Nile virus (WNV) circulation dynamics in the context of the urban environment is not yet elucidated. In this perspective, three groups of eight rock pigeons (Columbia livia) were inoculated with three WNV lineage 1 strains isolated in Italy between 2009 and 2012. The pigeons did not develop any clinical signs consistent with WNV acute infection. All animals seroconverted and shed virus up to 15 days post-infection by the oral or cloacal routes. In all infected groups viraemia lasted for 4 days post-infection. No WNV-specific gross or histological lesions were found in infected birds compared to control birds and immunohistochemistry remained constantly negative from all tissues. The reservoir competence index was also assessed and it ranged between 0·11 and 0·14. This study demonstrates that pigeons are competent reservoir hosts for Italian WNV lineage 1 circulating strains thus potentially posing a risk to the public health system. PMID:26493864

  2. A minimax approach to mean field games

    NASA Astrophysics Data System (ADS)

    Averboukh, Yu V.

    2015-07-01

    An initial boundary value problem for the system of equations of a determined mean field game is considered. The proposed definition of a generalized solution is based on the minimax approach to the Hamilton-Jacobi equation. We prove the existence of the generalized (minimax) solution using the Nash equilibrium in the auxiliary differential game with infinitely many identical players. We show that the minimax solution of the original system provides the \\varepsilon-Nash equilibrium in the differential game with a finite number of players. Bibliography: 34 titles.

  3. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, NM

    SciTech Connect

    Murphy, M.B.

    1999-02-01

    Advanced reservoir characterization techniques are being used at the Nash Draw Brushy Canyon Pool project to develop reservoir management strategies for optimizing oil recovery from this Delaware reservoir. The reservoir characterization, geologic modeling, 3-D seismic interpretation, and simulation studies have provided a detailed model of the Brushy Canyon zones. This model was used to predict the success of different reservoir management scenarios and to aid in determining the most favorable combination of targeted drilling, pressure maintenance, well stimulation, and well spacing to improve recovery from this reservoir.

  4. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2004-01-31

    The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  5. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2003-10-31

    The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  6. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2002-12-31

    The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  7. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2003-07-30

    The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  8. The balance between IL-17 and IL-22 produced by liver-infiltrating T-helper cells critically controls NASH development in mice.

    PubMed

    Rolla, Simona; Alchera, Elisa; Imarisio, Chiara; Bardina, Valentina; Valente, Guido; Cappello, Paola; Mombello, Cristina; Follenzi, Antonia; Novelli, Francesco; Carini, Rita

    2016-02-01

    The mechanisms responsible for the evolution of steatosis towards NASH (non-alcoholic steatohepatitis) and fibrosis are not completely defined. In the present study we evaluated the role of CD4(+) T-helper (Th) cells in this process. We analysed the infiltration of different subsets of CD4(+) Th cells in C57BL/6 mice fed on a MCD (methionine choline-deficient) diet, which is a model reproducing all phases of human NASH progression. There was an increase in Th17 cells at the beginning of NASH development and at the NASH-fibrosis transition, whereas levels of Th22 cells peaked between the first and the second expansion of Th17 cells. An increase in the production of IL (interleukin)-6, TNFα (tumour necrosis factor α), TGFβ (transforming growth factor β) and CCL20 (CC chemokine ligand 20) accompanied the changes in Th17/Th22 cells. Livers of IL-17(-/-) mice were protected from NASH development and characterized by an extensive infiltration of Th22 cells. In vitro, IL-17 exacerbated the JNK (c-Jun N-terminal kinase)-dependent mouse hepatocyte lipotoxicity induced by palmitate. IL-22 prevented lipotoxicity through PI3K (phosphoinositide 3-kinase)-mediated inhibition of JNK, but did not play a protective role in the presence of IL-17, which up-regulated the PI3K/Akt inhibitor PTEN (phosphatase and tensin homologue deleted on chromosome 10). Consistently, livers of IL-17(-/-) mice fed on the MCD diet displayed decreased activation of JNK, reduced expression of PTEN and increased phosphorylation of Akt compared with livers of wild-type mice. Hepatic infiltration of Th17 cells is critical for NASH initiation and development of fibrosis in mice, and reflects an infiltration of Th22 cells. Th22 cells are protective in NASH, but only in the absence of IL-17. These data strongly support the potentiality of clinical applications of IL-17 inhibitors that can prevent NASH by both abolishing the lipotoxic action of IL-17 and allowing IL-22-mediated protection. PMID:26558403

  9. Morphological and molecular characterization of Eimeria labbeana-like (Apicomplexa:Eimeriidae) in a domestic pigeon (Columba livia domestica, Gmelin, 1789) in Australia.

    PubMed

    Yang, Rongchang; Brice, Belinda; Elloit, Aileen; Ryan, Una

    2016-07-01

    An Eimeria species is described from a domestic pigeon (Columba livia domestica). Sporulated oocysts (n = 35) were subspherical, with a smooth bi-layered oocyst wall (1.0 μm thick). Oocysts measured 20.2 × 16.1 (22.0-18.9 × 15.7-18.9) μm, oocyst length/width (L/W) ratio, 1.38. Oocyst residuum and a polar granule were present. The micropyle was absent. Sporocysts are elongate-ovoid, 13.0 × 6.1 (14.5-12.5 × 5.5-7.0) μm, sporocyst L/W ratio, 2.13 (2.0-2.2), sporocyst residuum was present, composed of numerous granules in a spherical or ovoid mass. Each sporocyst contained 2 banana-shaped sporozoites, 12.3 × 3.5 (11.8-13.0 × 3.3-3.6) μm. A spherical-ellipsoid posterior refractile body was found in the sporozoites. A nucleus was located immediately anterior to the posterior refractile body. Molecular analysis was conducted at three loci; the 18S and 28S ribosomal RNA genes and the mitochondrial cytochrome oxidase gene (COI). At the 18S locus, the new isolate shared 98.0% genetic similarity with three Isospora isolates from Japan from the domestic pigeon (Columba livia domestica). At the 28S locus, it grouped separately and shared 92.4% and 92.5% genetic similarity with Isospora anthochaerae (KF766053) from a red wattlebird (Anthochaera carunculata) from Australia and an Isospora sp. (MS-2003 - AY283845) from a Himalayan grey-headed bullfinch (Pyrrhula erythaca) respectively. At COI locus, this new isolate was in a separate clade and shared 95.6% and 90.0% similarity respectively with Eimeria tiliquae n. sp. from a shingleback skink in Australia and an Eimeria sp. from a common pheasant (Phasianus colchicus) from America. Based on the morphological data, this isolate is most similar to Eimeria labbeana. As no molecular data for E. labbeana is available and previous morphological data is incomplete, we refer to the current isolate as E. labbeana-like. PMID:27080159

  10. Preliminary hydrologic data for wells tested in Nash Draw, near the proposed Waste Isolation Pilot Plant site, southeastern New Mexico

    USGS Publications Warehouse

    Richey, S.F.

    1987-01-01

    Hydrologic testing was conducted at wells WIPP-25, WIPP-26, WIPP-27, WIPP-28, WIPP-29, and WIPP-30 in Nash Draw near the Waste Isolation Pilot Plant site in southeastern New Mexico. The three water-bearing zones tested were the Magenta Dolomite Member of the Rustler Formation, Culebra Dolomite Member of the Rustler Formation, and the Rustler Formation-Salado Formation contact zone. Inflatable packers were used in a variety of test configurations. Tests conducted include bailing, recovery after perforation, shut in, slug, flow, and pressure pulse. Water pressure response in the tested zone was monitored by a pressure-transducer system. Preliminary hydrologic-test data are tabulated in chronological order for each well. (Lantz-PTT)

  11. Defining the Polar Vortex Edge Using an N2O: Potential Temperature Correlation Versus the Nash Criterion: A Comparison

    NASA Technical Reports Server (NTRS)

    Greenblatt, Jeffery B.; Jost, Hans-Juerg; Loewenstein, Max; Podolske, James R.; Bui, T. Paul; Hurst, Dale F.; Elkins, James W.; Herman, Robert L.; Webster, Christopher R.; Schauffler, Sue M.; Hipskind, R. Stephen (Technical Monitor)

    2001-01-01

    A prerequisite to study phenomena in the winter stratospheric polar vortex is the separation of measurements inside and outside the dynamical barrier of the vortex edge. We describe a technique to accurately determine the inner edge of the vortex boundary region from measurements of potential temperature and a trace gas, such as N2O, and apply it to in situ aircraft and balloon measurements from the SOLVE/THESE02000 Arctic campaign. The method may be used to refine the Nash algorithm, which, due to the inherently coarser resolution of potential vorticity on which it is dependent, may misidentify the inner edge by up to 466 km, and omit the identification of small, extra-vortex filaments within the vortex.

  12. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2002-09-30

    The overall objective of this project is to demonstrate that a development program-based on advanced reservoir management methods-can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry. This is the twenty-eighth quarterly progress report on the project. Results obtained to date are summarized.

  13. Caspase 3 inactivation protects against hepatic cell death and ameliorates fibrogenesis in a diet induced NASH model

    PubMed Central

    Thapaliya, Samjhana; Wree, Alexander; Povero, Davide; Inzaugarat, Maria Eugenia; Berk, Michael; Dixon, Laura; Papouchado, Bettina G.; Feldstein, Ariel E

    2014-01-01

    Background/Aims Hepatocyte cell death is a key feature of nonalcoholic steohepatitis (NASH). As the contribution of specific caspases remains unclear, our aim was to ascertain the effect of caspase 3 suppression on liver injury and fibrogenesis. Methods C57BL/6 wild-type (WT), and caspase 3 knock out (Casp3−/−) mice were placed on a methionine- and choline-deficient (MCD) diet for 6 weeks to induce steatohepatitis and liver fibrosis. Thereafter, liver injury, liver fibrosis and hepatocellular apoptosis were quantified in liver sections. Additionally, expression of proteins associated with liver inflammation and fibrogenesis were analyzed. Results WT mice fed MCD diet showed marked activation of caspase 3 in hepatocytes, in conjunction with steatohepatitis and increased hepatic triglyceride levels, hepatocyte ballooning, inflammation and fibrosis. Casp3−/− fed the MCD diet showed similar serum ALT levels and NAFLD activity scores (NAS) compared to WT MCD-fed mice. However Casp3−/− mice on the MCD diet showed a marked reduction in expression of transcripts for pro-fibrogenic genes i which translated into reduced hepatic collagen deposition. These changes were associated with decreased levels of apoptosis, and a significant reduction in the expression of cytokines involved in inflammatory signaling. Casp3−/− mice on the MCD showed a reduction in expression of chemokine receptor 2 (CCR2) leading to ameliorated infiltration of inflammatory lymphocyte antigen 6 complex, locus C1 (Ly6c) positive monocytes. Conclusion These findings support a prominent role for hepatocyte caspase 3 activation in NASH related apoptosis, fibrogenesis and fibrosis which in part is mediated via CCR2 dependent infiltration of Ly6c positive monocytes. PMID:24795036

  14. 77 FR 10553 - Match-E-Be-Nash-She-Wish Band of Pottawatomi Indians (Gun Lake)-Amendment to Liquor Beverage...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-22

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs Match-E-Be-Nash-She-Wish Band of Pottawatomi Indians (Gun Lake)-- Amendment to Liquor Beverage Control Ordinance AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice...

  15. Prevalence and risk factors for Campylobacter spp., Salmonella spp., Coxiella burnetii, and Newcastle disease virus in feral pigeons (Columba livia) in public areas of Montreal, Canada

    PubMed Central

    Gabriele-Rivet, Vanessa; Fairbrother, Julie-Hélène; Tremblay, Donald; Harel, Josée; Côté, Nathalie; Arsenault, Julie

    2016-01-01

    Feral pigeons (Columbia livia) can harbor a range of zoonotic pathogens. A transversal study was undertaken to estimate the prevalence of feral pigeons infected by various pathogens in public areas in Montreal, Quebec. Cloacal swabs from captured birds were cultured for Salmonella spp. and Campylobacter spp. and tested by real-time polymerase chain reaction (RT-PCR) for the detection of Coxiella burnetii. An oropharyngeal swab was also submitted to real-time reverse-transcription polymerase chain reaction (RRT-PCR) for the detection of Newcastle disease virus. Among the 187 pigeons tested from 10 public areas, 9.1% (95% CI: 3.0 to 15.2) were positive for Campylobacter spp. with all strains identified as Campylobacter jejuni. The Campylobacter status of birds was not associated with individual characteristics of birds, with the exception of body score. None of the pigeons tested positive for the other pathogens. Direct or indirect contacts with feral pigeons may constitute a potential risk for Campylobacter infection in humans. PMID:26733736

  16. Comparison of a Point-of-Care Glucometer and a Laboratory Autoanalyzer for Measurement of Blood Glucose Concentrations in Domestic Pigeons ( Columba livia domestica).

    PubMed

    Mohsenzadeh, Mahdieh Sadat; Zaeemi, Mahdieh; Razmyar, Jamshid; Azizzadeh, Mohammad

    2015-09-01

    Biochemical analysis is necessary for diagnosis and monitoring of diseases in birds; however, the small volume of blood that can be safely obtained from small avian species often limits laboratory diagnostic testing. Consequently, a suitable methodology requiring only a small volume of blood must be used. This study was designed to compare blood glucose concentrations in domestic pigeons ( Columba livia domestica) as measured by a commercial, handheld, human glucometer and a standard autoanalyzer. During the first phase of the study, whole blood samples obtained from 30 domestic pigeons were used to measure the blood glucose concentration with a glucometer, the packed cell volume (PCV), and the total erythrocyte count (nRBC). Plasma separated from the each sample was then used to obtain the plasma glucose concentration with the autoanalyzer. During the second phase of the study, 30 pigeons were assigned to 2 equal groups (n = 15). Hypoglycemia or hyperglycemia was induced in each group by intravenous injection of insulin or glucose, respectively. Blood was collected and processed, and glucose concentrations, PCV, and nRBC were measured as previously described. Linear-regression models demonstrated a significant relationship between results measured by the glucometer and autoanalyzer results from normoglycemic (correlation coefficient [R] = 0.43, P = .02), hypoglycemic (R = 0.95; P < .001), and hyperglycemic (R = 0.81; P < .001) birds. The results of this study suggest that we can predict the real blood-glucose concentration of pigeons by using results obtained by a glucometer. PMID:26378663

  17. Prevalence and risk factors for Campylobacter spp., Salmonella spp., Coxiella burnetii, and Newcastle disease virus in feral pigeons (Columba livia) in public areas of Montreal, Canada.

    PubMed

    Gabriele-Rivet, Vanessa; Fairbrother, Julie-Hélène; Tremblay, Donald; Harel, Josée; Côté, Nathalie; Arsenault, Julie

    2016-01-01

    Feral pigeons (Columbia livia) can harbor a range of zoonotic pathogens. A transversal study was undertaken to estimate the prevalence of feral pigeons infected by various pathogens in public areas in Montreal, Quebec. Cloacal swabs from captured birds were cultured for Salmonella spp. and Campylobacter spp. and tested by real-time polymerase chain reaction (RT-PCR) for the detection of Coxiella burnetii. An oropharyngeal swab was also submitted to real-time reverse-transcription polymerase chain reaction (RRT-PCR) for the detection of Newcastle disease virus. Among the 187 pigeons tested from 10 public areas, 9.1% (95% CI: 3.0 to 15.2) were positive for Campylobacter spp. with all strains identified as Campylobacter jejuni. The Campylobacter status of birds was not associated with individual characteristics of birds, with the exception of body score. None of the pigeons tested positive for the other pathogens. Direct or indirect contacts with feral pigeons may constitute a potential risk for Campylobacter infection in humans. PMID:26733736

  18. Evaluation of hepatobiliary scintigraphy as an indicator of hepatic function in domestic pigeons (Columba livia) before and after exposure to ethylene glycol.

    PubMed

    Hadley, Tarah L; Daniel, Gregory B; Rotstein, David S; Avenell, James S; Zagaya, Nancy; Jones, Michael P

    2007-01-01

    This study investigated the use of quantitative hepatobiliary scintigraphy to assess liver function in 14 white Carneaux pigeons (Columba livia). Liver scintigraphy using 99mTc-mebrofenin was performed and liver function was quantified using deconvolutional analysis and the area under the normalized heart time-activity curve as previously described in the dog and horse. Liver biopsies were performed in all birds before and after toxin-induced liver damage with ethylene glycol. Before the induction of liver disease, all biopsy specimens showed varying degrees of granulomatous inflammation. After ethylene glycol administration, hepatic lesions were scored and compared with scintigraphic findings. Scintigraphic results showed a significant decrease (P = 0.04) in hepatic function using the area under the normalized time-activity curve. There was good correlation between the overall histologic score posttoxin exposure and scintigraphic measures of liver function (P < 0.03). Based upon these preliminary results, the area under the heart time-activity curve can determine hepatic extraction as a measure of hepatic parenchymal cell function. The results also showed that worsening hepatic cellular function correlated with increased histologic damage to the liver. The use of hepatobiliary scintigraphy using 99mTc-mebrofenin to determine liver function in pigeons has not been previously reported. Additional studies are warranted to evaluate the application of this technique in clinical patients and to establish the sensitivity of this technique. PMID:17385376

  19. Ultrasound therapy for the prevention and correction of contractures and bone mineral loss associated with wing bandaging in the domestic pigeon (Columba livia).

    PubMed

    Wimsatt, J; Dressen, P; Dennison, C; Turner, A S

    2000-06-01

    Figure-of-eight wing bandaging is widely used to treat wing injuries, to immobilize wings before and after fracture repair, and during transient wing paralysis. However, prolonged bandaging can lead to bone loss and to contractures and reduced range of joint motion. Studies evaluating the efficacy of therapeutic ultrasound to reverse and prevent bandaging-associated contractures in pigeons (Columba livia) showed a significant increase in elbow and carpal extension after 10 twice weekly ultrasound treatments when started either 4 or 11 days after bandage placement. In addition, after 42 days of wing bandaging, three ultrasound treatments stimulated a faster reversal of carpal wing rotation loss than removal of the bandage over the 10-day treatment period. Finally, bone loss in response to 28 days of bandaging was significant, progressed at 2.8% per week, and was not affected by ultrasound treatment twice weekly during this period. Therefore, therapeutic ultrasound prevented and reversed loss of wing extension associated with figure-of-eight bandaging but did not lessen the disuse osteoporosis created by bandaging in these birds. PMID:10982131

  20. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, NM

    SciTech Connect

    Mark B. Murphy

    2005-09-30

    The Nash Draw Brushy Canyon Pool in Eddy County New Mexico was a cost-shared field demonstration project in the U.S. Department of Energy Class III Program. A major goal of the Class III Program was to stimulate the use of advanced technologies to increase ultimate recovery from slope-basin clastic reservoirs. Advanced characterization techniques were used at the Nash Draw Pool (NDP) project to develop reservoir management strategies for optimizing oil recovery from this Delaware reservoir. The objective of the project was to demonstrate that a development program, which was based on advanced reservoir management methods, could significantly improve oil recovery at the NDP. Initial goals were (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to other oil and gas producers. Analysis, interpretation, and integration of recently acquired geological, geophysical, and engineering data revealed that the initial reservoir characterization was too simplistic to capture the critical features of this complex formation. Contrary to the initial characterization, a new reservoir description evolved that provided sufficient detail regarding the complexity of the Brushy Canyon interval at Nash Draw. This new reservoir description was used as a risk reduction tool to identify 'sweet spots' for a development drilling program as well as to evaluate pressure maintenance strategies. The reservoir characterization, geological modeling, 3-D seismic interpretation, and simulation studies have provided a detailed model of the Brushy Canyon zones. This model was used to predict the success of different reservoir management scenarios and to aid in determining the most favorable combination of targeted drilling, pressure maintenance, well stimulation, and well spacing to improve recovery from this reservoir. An Advanced

  1. Nash and integrated solutions in a just-in-time seller-buyer supply chain with buyer's ordering cost reductions

    NASA Astrophysics Data System (ADS)

    Lou, Kuo-Ren; Wang, Lu

    2016-05-01

    The seller frequently offers the buyer trade credit to settle the purchase amount. From the seller's prospective, granting trade credit increases not only the opportunity cost (i.e., the interest loss on the buyer's purchase amount during the credit period) but also the default risk (i.e., the rate that the buyer will be unable to pay off his/her debt obligations). On the other hand, granting trade credit increases sales volume and revenue. Consequently, trade credit is an important strategy to increase seller's profitability. In this paper, we assume that the seller uses trade credit and number of shipments in a production run as decision variables to maximise his/her profit, while the buyer determines his/her replenishment cycle time and capital investment as decision variables to reduce his/her ordering cost and achieve his/her maximum profit. We then derive non-cooperative Nash solution and cooperative integrated solution in a just-in-time inventory system, in which granting trade credit increases not only the demand but also the opportunity cost and default risk, and the relationship between the capital investment and the ordering cost reduction is logarithmic. Then, we use a software to solve and compare these two distinct solutions. Finally, we use sensitivity analysis to obtain some managerial insights.

  2. Leaf gas exchange of Andropogon gerardii Vitman, Panicum virgatum L., and Sorghastrum nutans (L.) Nash in a tallgrass prairie

    NASA Technical Reports Server (NTRS)

    Polley, H. W.; Norman, J. M.; Arkebauer, T. J.; Walter-Shea, E. A.; Greegor, D. H., Jr.; Bramer, B.

    1992-01-01

    Net CO2 assimilation as a function of internal CO2 and stomatal conductance to water vapor were measured on blades of the C4 grasses Andropogon gerardii Vitman, Panicum virgatrum L., and Sorghastrum nutans (L.) Nash in northeast Kansas over two growing seasons to determine the comparative physiological responses of these dominant grasses of the tallgrass prairie to environmental variables. The response of dark respiration to temperature and of net assimilation to CO2 concentration and absorbed quantum flux differed little among species. A. gerardii had lower potential photosynthetic rates at internal CO2 concentrations below saturation than P. virgatum and S. nutans, but net assimilation under ambient conditions was similar in the three species. Net assimilation and both the initial slope of assimilation versus internal CO2 curves and the maximum potential assimilation rate decreased as leaf water potential declined in blades of A. gerardii and S. nutans. Changes in assimilation capacity were paralleled by changes in stomatal conductance that were similar in all three species. The strong correlations among processes regulating leaf CO2 assimilation and transpiration in A. gerardii, P. virgatum, and S. nutans suggest that the processes are tightly and similarly coupled in these grasses over a wide range of environmental conditions encountered in the tallgrass prairie.

  3. Potential of vetiver (vetiveria zizanioides (L.) Nash) for phytoremediation of petroleum hydrocarbon-contaminated soils in Venezuela.

    PubMed

    Brandt, Regine; Merkl, Nicole; Schultze-Kraft, Rainer; Infante, Carmen; Broll, Gabriele

    2006-01-01

    Venezuela is one of the largest oil producers in the world. For the rehabilitation of oil-contaminated sites, phytoremediation represents a promising technology whereby plants are used to enhance biodegradation processes in soil. A greenhouse study was conducted to determine the tolerance of vetiver (Vetiveria zizanioides (L.) Nash) to a Venezuelan heavy crude oil in soil. Additionally, the plant's potential for stimulating the biodegradation processes of petroleum hydrocarbons was tested under the application of two fertilizer levels. In the presence of contaminants, biomass and plant height were significantly reduced. As for fertilization, the lower fertilizer level led to higher biomass production. The specific root surface area was reduced under the effects of petroleum. However, vetiver was found to tolerate crude-oil contamination in a concentration of 5% (w/w). Concerning total oil and grease content in soil, no significant decrease under the influence of vetiver was detected when compared to the unplanted control. Thus, there was no evidence of vetiver enhancing the biodegradation of crude oil in soil under the conditions of this trial. However, uses of vetiver grass in relation to petroleum-contaminated soils are promising for amelioration of slightly polluted sites, to allow other species to get established and for erosion control. PMID:17305302

  4. Flexible learning and use of multiple-landmark information by pigeons (Columba livia) in a touch screen-based goal searching task.

    PubMed

    Ushitani, Tomokazu; Jitsumori, Masako

    2011-08-01

    Three touch screen-based experiments were conducted to investigate whether pigeons would learn to use configural information about a goal's location in relation to a multiple-landmark array. In Experiment 1, 4 pigeons (Columba livia) were trained to peck a computer monitor at a location that constituted the third vertex of a hypothetical triangle defined by 2 different landmarks. The landmarks appeared in 3 orientations during the training, and the pigeons' goal-searching ability easily transferred to the landmarks presented in 3 novel orientations. Each landmark was asymmetric, so we next examined whether the pigeons used (a) the small-scale, local orientation information that could be inferred from each landmark individually, or (b) the large-scale, configural information that could be inferred from the spatial arrangement of multiple landmarks taken as a whole. Even when each single landmark appeared by itself, the pigeons were able to locate the goal accurately, suggesting that the large-scale, configural information was not essential. However, when 1 landmark locally pointed to a location that was consistent with the triangular configuration and the other landmark locally pointed to a different location, the pigeons predominantly pecked at the configurally array-consistent location. These results suggest that the pigeons redundantly learned both the large-scale, configural strategy and the local, single-landmark strategy, but they mainly used the latter information, and used the former information solely to disambiguate conflicts when the 2 landmarks pointed toward different targets. Such flexible learning and use of redundant information may reflect the pigeons' adaptation to unstable wild environments during their evolutionary history. PMID:21574692

  5. Prevalence of ectoparasites in free-range backyard chickens, domestic pigeons (Columba livia domestica) and turkeys of Kermanshah province, west of Iran.

    PubMed

    Rezaei, Farid; Hashemnia, Mohammad; Chalechale, Abdolali; Seidi, Shahin; Gholizadeh, Maryam

    2016-06-01

    This study was carried out on free-range backyard chickens, domestic pigeons (Columba livia domestica) and turkeys from May 2012 to April 2013 to determine the prevalence and identify the species of ectoparasites in Kermanshah province, west of Iran. Of the total of 600 free-range backyard chickens (185 ♂ and 415 ♀), 700 domestic pigeons (278 ♂ and 422 ♀) and 150 turkeys (53 ♂ and 97 ♀), 389 (64.83 %), 608 (86.85 %) and 54 (36 %) were infected with one or more parasites respectively. Eleven ectoparasites species including five of lice (50.16 % Menacanthus stramineus, 13.66 % Menopon gallinae, 4.83 % Cuclotogaster heterographus, 5.16 % Goniocotes gallinae, 2.33 % Goniodes gigas), three of mites (26.33 % Dermanyssus gallinae, 8.5 % Ornithonyssus bursa, 7 % Cnemidocoptes mutans), one of tick (78.66 % Argas persicus) and two of flea (12.33 % Echidnophaga gallinacea, 2 % Pulex irritans) were found in the backyard chickens. The domestic pigeons were infected with six species of parasites including: Columbicola columbae (61.7 %), M. gallinae (10.43 %), M. stramineus (9 %), D. gallinae (8.28 %), Argas reflexus (74.14 %) and Pseudolynchia canariensis (27.7 %). The ectoparasites species recorded in turkeys were M. gallinae (14 %), M. stramineus (8 %), D. gallinae (12.66 %), C. mutans (6 %), A. persicus (24.66 %) and E. gallinacean (6 %). This is the first survey to determine the prevalence and identify the species of ectoparasites among free-range backyard chicken, domestic pigeons and turkeys in Kermanshah province. The high prevalence rate of ectoparasites in free-range backyard chickens and domestic pigeons indicates that parasitic infection is a common problem in this area. PMID:27413319

  6. Evaluation of Two Miniplate Systems and Figure-of-eight Bandages for Stabilization of Experimentally Induced Ulnar and Radial Fractures in Pigeons ( Columba livia ).

    PubMed

    Bennert, Beatrice M; Kircher, Patrick R; Gutbrod, Andreas; Riechert, Juliane; Hatt, Jean-Michel

    2016-06-01

    Although plate fixation has advantages over other fixation methods for certain indications, it is rarely used in avian surgery, especially in birds that weigh less than 1000 g. Exceptionally small plating systems for these birds are required, which are relatively expensive and difficult to insert. To study avian fracture healing after repair using miniplates, we evaluated 2 steel miniplate systems in 27 pigeons ( Columba livia ) divided into 4 groups. In each pigeon, the left ulna and radius were transected and the ulna was repaired with a bone plate. In groups A and B, a 1.3-mm adaption plate was applied without and with a figure-of-eight bandage; in groups C and D, a 1.0-mm compression plate was applied without and with a bandage, respectively. Healing was evaluated with radiographs after 3, 14, and 28 days; flight tests were conducted after 14, 21, and 28 days; and the wing was macroscopically examined after euthanasia of birds on day 28. Fractures healed without bending or distortion of the plate in all 27 birds, and no significant differences in healing were found between treatment groups. At the end of the study, 23 pigeons (85.2%) showed good or very good flight ability. Results show the 1.3-mm adaption plate and the 1.0-mm compression plate meet the requirements for avian osteosynthesis and can be recommended for fracture repair of the ulna or other long bones in birds weighing less than 500 g. The application of a figure-of-eight bandage might be beneficial in fracture healing. PMID:27315377

  7. Prevalence of parasites and associated risk factors in domestic pigeons (Columba livia domestica) and free-range backyard chickens of Sistan region, east of Iran.

    PubMed

    Radfar, Mohammad Hossein; Khedri, Javad; Adinehbeigi, Keivan; Nabavi, Reza; Rahmani, Khatereh

    2012-10-01

    This study was carried out on free-range backyard chickens and domestic pigeons (Columba livia domestica) from December 2010 to November 2011 to determine the prevalence, intensity and species of internal and external parasites in Sistan region, east of Iran. Of the total of 59 (27 males and 32 females) free-range backyard chickens and 46 (26 males and 20 females) domestic pigeons inspected, 55 (93.22 %) and 39 (84.78 %) were infected respectively. Ten species of free-range backyard chickens parasites were collected from alimentary canals, body, head and neck, comprising of 3 species of nematodes, 4 species of cestodes and 3 species of ectoparasites as follows: Ascaridia galli (16.94 %), Heterakis gallinarum (23.72 %), Subulura brumpti (67.79 %), Raillietina tetragona (35.59 %), Raillietina echinobothrida (27.11 %), Raillietina cesticillus (15.25 %), Choanotaenia infundibulum (40.67 %), Argas persicus (16.94 %), Menopen gallinae (55.93 %) and Menacanthus stramineus (33.89 %). The domestic pigeons were infected with seven species of parasites including 2 species of nematodes, 2 species of cestodes and 3 species of ectoparasites as follows: Ascaridia colombae (15.21 %), Hadjelia truncata (17.39 %), Raillietina tetragona (26.08 %), Raillietina echinobothrida (28.26 %), Argas reflexus (13.04 %), Menopen gallinae (32.60 %), Columbicola Columba (41.30 %). This is the first survey to determine the prevalence and intensity of parasites among free-range backyard chicken and domestic pigeon species in Sistan region. PMID:24082532

  8. Comparison between lead levels in blood and bone tissue of rock doves (Columba livia) treated with lead acetate or exposed to the environment of Alcala de Henares

    SciTech Connect

    Tejedor, M.C.; Gonzalez, M.

    1992-06-01

    The increase in the amount of lead released into the environment in developed countries during the last two to three decades has resulted in a significant increase in lead levels in organisms from completely different environments. Several surveys have been made in urban areas with high traffic densities in an attempt to identify plant and animal species that might reflect environmental metal concentrations so that those species could be used as sensitive biological indicators of heavy metal contamination. Studies of lead accumulation in U.K. rock doves imply that use of this species as a pollution indicator would facilitate periodic monitoring of chronic lead exposure conditions in the urban environment. Laboratory investigations cannot readily reflect environmental conditions since the validity of extrapolating laboratory results, where high doses are administered over short-time periods, to the natural environment has been seriously questioned. The present study was made on four rock dove (Columbia livia) populations: two groups (males and females) were dosed with lead acetate in the laboratory and two groups of males were housed in different parts of the city of Alcala de Henares. Data on lead bioaccumulation were collected in two situations: the first was in a laboratory with controlled amounts of lead, while in the second situation the amounts reflected the actual environmental levels in Alcala de Henares. Lead levels were determined in two tissues: blood, which is the target of first impact in possible acute situations; and bone, which is the main tissue where lead accumulates and, therefore, very important during chronic exposure. The study focused on the following three items: (1) lead tissue distribution; (2) variation with habitat; and (3) an evaluation of the levels of lead contamination in the city of Alcala de Henares. 19 refs., 3 figs., 1 tab.

  9. The role of beta-adrenergic receptors in the cutaneous water evaporation mechanism in the heat-acclimated pigeon (Columba livia).

    PubMed

    Ophir, E; Arieli, Y; Raber, P; Marder, J

    2000-01-01

    The effects of selective and non-selective beta-adrenergic agents on cutaneous water evaporation (CWE) were studied in hand-reared rock pigeons (Columba livia). CWE was measured by the vapor diffusive resistance method, using a transient porometer. Intramuscular and subcutaneous injections of a non-selective beta-adrenergic antagonist (propranolol) or a selective beta(2)-adrenergic antagonist (ICI-118551) to heat-acclimated (HAc) pigeons at ambient temperature (T(a)) of 24 degrees C resulted in intensive CWE. The CWE values that were triggered by propranolol and ICI-118551 (18.59+/-0.73 and 16.48+/-0.70 mg cm(-2) h(-1), respectively) were close to those induced by heat exposure (17.62+/-1.40 mg cm(-2) h(-1)). Subcutaneous administration of propranolol produced local response. Intramuscular injection of salbutamol (selective beta(2)-adrenergic agonist) to HAc pigeons drastically diminished CWE induced by either propranolol, metoprolol or heat exposure. Such manipulations also enhanced panting at relatively low T(a)s (42 degrees C). The inhibition of beta(1)-adrenergic receptors by metoprolol increased CWE, while inhibition by atenolol produced no change from basal values. This difference may be attributed to their distinctive nature in penetrating the blood-brain barrier. Our findings indicate a regulatory pathway for CWE consisting of both beta(1)- and beta(2)-adrenergic receptors. We suggest that the beta(1)-adrenergic effect is restricted mainly to the CNS, while the beta(2)-adrenergic effect takes place at the effector level. We postulate this level to be either the cutaneous microvasculature or the epidermal layer. PMID:10779732

  10. The change in heat shock protein expression in avermectin induced neurotoxicity of the pigeon (Columba livia) both in vivo and in vitro.

    PubMed

    Li, Ming; Wang, Xian-Song; Xu, Feng-Ping; Liu, Shuang; Xu, Shi-Wen; Li, Shu

    2014-12-01

    The expression of heat shock proteins (Hsps) commonly increases to provide neuroprotection when brain tissues are under stress conditions. Residues of avermectins (AVMs) have neurotoxic effects on a number of non-target organisms. The aim of this study was to investigate the effects of AVM exposure on the expression levels of Hsp 60, Hsp 70 and Hsp 90 for pigeon (Columba livia) neurons both in vivo and in vitro. The results showed that in general, the mRNA and protein levels of Hsps were increased in treated groups relative to control groups after AVM exposure for 30d, 60d and 90d in the cerebrum, cerebellum and optic lobe in vivo. However, AVM exposure had no significant effects on the transcription expression of Hsps for 90d in the optic lobe and decreased the translation expression of Hsps significantly for 90d in the optic lobe. In vitro, the LC50 of avermectin for King pigeon neurons is between 15μgL(-1) and 20μgL(-1). Following AVM (2.5-20μgL(-1)) exposure, the mRNA expression of the 3 Hsps was up-regulated to different degrees. Compared with the control groups, a significant decrease, a remarkable increase and a non-significant change was found in the protein expression of Hsp 60, Hsp 70 and Hsp 90 separately following AVM (2.5-20μgL(-1)) exposure. Based on these results, we conclude that AVM exposure can induce a protective stress response in pigeons by means of promoting the mRNA and protein expression of Hsps under in vivo and in vitro conditions, thus easing the neurotoxic effects of AVM to some extent. PMID:25202854

  11. Color differences among feral pigeons (Columba livia) are not attributable to sequence variation in the coding region of the melanocortin-1 receptor gene (MC1R)

    PubMed Central

    2013-01-01

    Background Genetic variation at the melanocortin-1 receptor (MC1R) gene is correlated with melanin color variation in many birds. Feral pigeons (Columba livia) show two major melanin-based colorations: a red coloration due to pheomelanic pigment and a black coloration due to eumelanic pigment. Furthermore, within each color type, feral pigeons display continuous variation in the amount of melanin pigment present in the feathers, with individuals varying from pure white to a full dark melanic color. Coloration is highly heritable and it has been suggested that it is under natural or sexual selection, or both. Our objective was to investigate whether MC1R allelic variants are associated with plumage color in feral pigeons. Findings We sequenced 888 bp of the coding sequence of MC1R among pigeons varying both in the type, eumelanin or pheomelanin, and the amount of melanin in their feathers. We detected 10 non-synonymous substitutions and 2 synonymous substitution but none of them were associated with a plumage type. It remains possible that non-synonymous substitutions that influence coloration are present in the short MC1R fragment that we did not sequence but this seems unlikely because we analyzed the entire functionally important region of the gene. Conclusions Our results show that color differences among feral pigeons are probably not attributable to amino acid variation at the MC1R locus. Therefore, variation in regulatory regions of MC1R or variation in other genes may be responsible for the color polymorphism of feral pigeons. PMID:23915680

  12. Fast food diet mouse: novel small animal model of NASH with ballooning, progressive fibrosis, and high physiological fidelity to the human condition

    PubMed Central

    Krishnan, Anuradha; Viker, Kimberly; Sanderson, Schuyler; Cazanave, Sophie; McConico, Andrea; Masuoko, Howard; Gores, Gregory

    2011-01-01

    Although there are small animal platforms that recapitulate some of the histological features of nonalcoholic fatty liver disease, there are no small animal models of nonalcoholic steatohepatitis (NASH) with consistent hepatocellular ballooning and progressive fibrosis that also exhibit fidelity to the human condition physiologically. We examined the metabolic and histological effects of a diet on the basis of the composition of “fast food” (high saturated fats, cholesterol, and fructose). Mice (n = 8 in each group) were assigned to diets as follows: 1) standard chow (SC), i.e., 13% energy as fat [1% saturated fatty acids (SFA)], 2) high fat (HF), i.e., 60% energy as fat (1% SFA), and 3) fast food (FF), i.e., 40% energy as fat (12% SFA, 2% cholesterol). All three diets were supplemented with high fructose. All diets produced obesity. The HF and FF diets produced insulin resistance. Liver histology was normal in animals fed the SC diet. Steatohepatitis with pronounced ballooning and progressive fibrosis (stage 2) was observed in mice fed the FF diet. Although the HF diet produced obesity, insulin resistance, and some steatosis; inflammation was minimal, and there was no increase in fibrosis. The FF diet produced a gene expression signature of increased fibrosis, inflammation, and endoplasmic reticulum stress and lipoapoptosis. A diet based on high cholesterol, high saturated fat, and high fructose recapitulates features of the metabolic syndrome and NASH with progressive fibrosis. This represents a novel small animal model of fibrosing NASH with high fidelity to the human condition. These results highlight the contribution of dietary composition to the development of nonalcoholic fatty liver disease and NASH. PMID:21836057

  13. Reactive approach motivation (RAM) for religion.

    PubMed

    McGregor, Ian; Nash, Kyle; Prentice, Mike

    2010-07-01

    In 3 experiments, participants reacted with religious zeal to anxious uncertainty threats that have caused reactive approach motivation (RAM) in past research (see McGregor, Nash, Mann, & Phills, 2010, for implicit, explicit, and neural evidence of RAM). In Study 1, results were specific to religious ideals and did not extend to merely superstitious beliefs. Effects were most pronounced among the most anxious and uncertainty-averse participants in Study 1 and among the most approach-motivated participants in Study 2 (i.e., with high Promotion Focus, Behavioral Activation, Action Orientation, and Self-Esteem Scale scores). In Studies 2 and 3, anxious uncertainty threats amplified even the most jingoistic and extreme aspects of religious zeal. In Study 3, reactive religious zeal occurred only among participants who reported feeling disempowered in their everyday goals in life. Results support a RAM view of empowered religious idealism for anxiety management (cf. Armstrong, 2000; Inzlicht, McGregor, Hirsch, & Nash, 2009). PMID:20565192

  14. Kupffer cell depletion attenuates leptin-mediated methoxamine-stimulated portal perfusion pressure and thromboxane A2 release in a rodent model of NASH-cirrhosis.

    PubMed

    Yang, Ying-Ying; Huang, Yi-Tsau; Tsai, Tung-Hu; Hou, Ming-Chih; Lee, Fa-Yauh; Lee, Shou-Dong; Lin, Han-Chieh

    2012-12-01

    Cirrhotic portal hypertension is characterized by increased hepatic oxidative stress, AA (arachidonic acid)-derived TXA(2) (thromboxane A(2)) release and exaggerated hepatic response to the α-adrenergic agonist MTX (methoxamine). Besides promoting hepatic fibrosis, the role of hyperleptinaemia in the modulation of vascular response in NASH (non-alcoholic steatohepatitis) rat livers remains unknown. The aim of the present study was to explore the possible links between hyperleptinaemia and the disarrangement in the hepatic microcirculation. NASH-cirrhosis with hyperleptinaemia was induced in lean rats by feeding with an HF/MCD (high-fat/methionine-choline-deficient) diet. Portal haemodynamics, various substances, protein and mRNA expression and PUFA (polyunsaturated fatty acid) composition were measured. Finally, the effects of leptin pre-infusion on TXA(2) release and concentration-PPP (portal perfusion pressure) curves in response to MTX were evaluated by simultaneously pre-treatment with the Kupffer cell inactivators GdCl(3) (gadolinium chloride) or EC (encapsulated clodronate), the TXS (TXA(2) synthase) inhibitor furegrelate, the TP receptor (TXA(2) receptor) antagonist SQ29548 and the dual TXS/TP receptor antagonist BM567. In HF/MCD+leptin-lean rats, cirrhosis-induced PPP and MTX hyper-responsiveness were associated with increased hepatic TXA(2) production, TBARS (thiobarbituric acid-reacting substances) levels and the AA (arachidonic acid)/n-3 PUFA ratio, and up-regulation of hepatic leptin, FAS (fatty acid synthase), NADPH oxidase subunits, TXS, TP receptor, TGFβ(1) (transforming growth factor β(1)) proteins and mRNAs. Pre-infusion of leptin significantly enhanced MTX-stimulated PPP elevation and TXA(2) release, which were attenuated by GdCl(3) and EC pre-treatment. Concomitantly pre-incubation with BM567, but not furegrelate or SQ29548, significantly abolished the leptin-enhanced MTX-stimulated increase in PPP in NASH-cirrhotic rats. Hyperleptinaemia

  15. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2001-10-31

    The Nash Draw Brushy Canyon Pool (NDP) in southeast New Mexico is one of the nine projects selected in 1995 by the U.S. Department of Energy (DOE) for participation in the Class III Reservoir Field Demonstration Program. The goals of the DOE cost-shared Class Program are to: (1) extend economic production, (2) increase ultimate recovery, and (3) broaden information exchange and technology application. Reservoirs in the Class III Program are focused on slope basin and deep-basin clastic depositional types. Production at the NDP is from the Brushy Canyon formation, a low-permeability turbidite reservoir in the Delaware Mountain Group of Permian, Guadalupian age. A major challenge in this marginal-quality reservoir is to distinguish oil-productive pay intervals from water-saturated non-pay intervals. Because initial reservoir pressure is only slightly above bubble-point pressure, rapid oil decline rates and high gas/oil ratios are typically observed in the first year of primary production. Limited surface access, caused by the proximity of underground potash mining and surface playa lakes, prohibits development with conventional drilling. Reservoir characterization results obtained to date at the NDP show that a proposed pilot injection area appears to be compartmentalized. Because reservoir discontinuities will reduce effectiveness of a pressure maintenance project, the pilot area will be reconsidered in a more continuous part of the reservoir if such areas have sufficient reservoir pressure. Most importantly, the advanced characterization results are being used to design extended reach/horizontal wells to tap into predicted ''sweet spots'' that are inaccessible with conventional vertical wells. The activity at the NDP during the past year has included the completion of the NDP Well No.36 deviated/horizontal well and the completion of additional zones in three wells, the design of the NDP No.33 directional/horizontal well, The planning and regulatory approval for the

  16. The effect of cocoa supplementation on hepatic steatosis, reactive oxygen species and LFABP in a rat model of NASH

    PubMed Central

    2011-01-01

    Background Non alcoholic steatohepatitis is hypothesised to develop via a mechanism involving fat accumulation and oxidative stress. The current study aimed to investigate if an increase in oxidative stress was associated with changes in the expression of liver fatty acid binding protein in a rat model of non alcoholic steatohepatitis and whether cocoa supplementation attenuated those changes. Methods Female Sprague Dawley rats were fed a high fat control diet, a high fat methionine choline deficient diet, or one of four 12.5% cocoa supplementation regimes in combination with the high fat methionine choline deficient diet. Results Liver fatty acid binding protein mRNA and protein levels were reduced in the liver of animals with fatty liver disease when compared to controls. Increased hepatic fat content was accompanied by higher levels of oxidative stress in animals with fatty liver disease when compared to controls. An inverse association was found between the levels of hepatic liver fatty acid binding protein and the level of hepatic oxidative stress in fatty liver disease. Elevated NADPH oxidase protein levels were detected in the liver of animals with increased severity in inflammation and fibrosis. Cocoa supplementation was associated with partial attenuation of these pathological changes, although the severity of liver disease induced by the methionine choline deficient diet prevented complete reversal of any disease associated changes. Red blood cell glutathione was increased by cocoa supplementation, whereas liver glutathione was reduced by cocoa compared to methionine choline deficient diet fed animals. Conclusion These findings suggest a potential role for liver fatty acid binding protein and NADPH oxidase in the development of non alcoholic steatohepatitis. Furthermore, cocoa supplementation may have be of therapeutic benefit in less sever forms of NASH. PMID:22081873

  17. Sarcocystis calchasi has an expanded host range and induces neurological disease in cockatiels (Nymphicus hollandicus) and North American rock pigeons (Columbia livia f. dom.).

    PubMed

    Olias, Philipp; Maier, Kristina; Wuenschmann, Arno; Reed, Leslie; Armién, Aníbal G; Shaw, Daniel P; Gruber, Achim D; Lierz, Michael

    2014-02-24

    Pigeon protozoal encephalitis (PPE) is an emerging central nervous system disease of pigeons (Columba livia f. domestica) caused by the apicomplexan parasite Sarcocystis calchasi. The intermediate host specificity of S. calchasi had been considered high, as domestic chickens were resistant to experimental infection. Here, we have re-evaluated this concept and expanded the known host range of S. calchasi by experimental infection of cockatiels (Nymphicus hollandicus), a species distantly related to pigeons. In this work, a group of eight cockatiels were experimentally infected with S. calchasi, which resulted in a biphasic central nervous system disease that paralleled PPE in many aspects, albeit with a more diverse pathology. All cockatiels became lethargic and polyuric between days 7 and 13 pi and during that time schizonts of S. calchasi were found primarily in the liver and spleen accompanied by necrosis and inflammation. As with pigeons, neurological signs occurred during a chronic phase of the disease in three cockatiels between 57 and 63 dpi. However, all five cockatiels necropsied in that period, or at the end of the trial at 76 dpi, had a severe lymphohistiocytic and necrotizing encephalitis. No tissue cysts were found in the heart, and cockatiels infected with 10(5) sporocysts only had a negligible parasite load in skeletal muscles despite the presence of severe central nervous system lesions. Notably, intralesional schizonts were identified in the brain of one cockatiel. In contrast to previous results, intralesional schizonts were also identified in the brains of three of six naturally infected pigeons from Minnesota and Missouri examined as part of an epidemiological investigation. In both the cockatiel and the pigeons, tissue cysts were found concurrently with schizonts suggesting an uncommon phenomenon in the Sarcocystis life cycle. Based on the results of this study, transmission of S. calchasi to avian species other than the domestic pigeon is

  18. Effect of egg weight on composition, embryonic growth, and expression of amino acid transporter genes in yolk sac membranes and small intestines of the domestic pigeon (Columba livia).

    PubMed

    Chen, M X; Li, X G; Yan, H C; Wang, X Q; Gao, C Q

    2016-06-01

    The objective of this study was to investigate the effect of egg weight on the composition of the egg, the growth of the embryo, and the expression of amino acid transporter genes in the yolk sac membranes and small intestines of the domestic pigeon (Columba livia). A total of 240 fertilized eggs were collected and divided into two groups based on the weight of the eggs, light (LE) and heavy (HE). The composition of 20 eggs from each group was measured, and the remaining eggs were weighed and placed in an incubator. On embryonic days (E) 9, 11, 13, and 15 and day of hatch (DOH), 15 embryos/hatchlings from each group were measured for embryonic growth, and samples were collected. The HE had heavier yolk and albumen weights than the LE (P < 0.01). Compared with the LE, the HE had heavier yolk-free embryonic body and yolk sac weights from E13 to DOH (P < 0.05). Additionally, the HE had larger yolk sac membrane weights from E13 to E15 (P < 0.05) and had more residual yolk sac content on DOH than those of the LE (P < 0.01). The yolk absorption was greater for the HE than for the LE from E11 to E13 (P < 0.05). Furthermore, the abundance of CAT2 and PepT1 mRNA in the yolk sac membranes was greater in the HE than in the LE on E13 (P < 0.05). Compared with the LE, the gene expression of EAAT2 in the intestine on E13 was greater in the HE, whereas the expression of EAAT3 was lower in the HE (P < 0.05). Taken together, our results suggest that egg weight influenced the composition of the eggs, embryonic development, and expression of amino acid transporter genes in the yolk sac membranes and small intestines of pigeon embryos. PMID:26957627

  19. Growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (Columba livia).

    PubMed

    Gao, C Q; Yang, J X; Chen, M X; Yan, H C; Wang, X Q

    2016-04-01

    Two experiments were conducted to fit growth curves, and determine age-related changes in carcass characteristics, organs, serum biochemical parameters, and gene expression of intestinal nutrient transporters in domestic pigeon (Columba livia). In experiment 1, body weight (BW) of 30 pigeons was respectively determined at 1, 3, 7, 14, 21, 28, and 35 days old to fit growth curves and to describe the growth of pigeons. In experiment 2, eighty-four 1-day-old squabs were grouped by weight into 7 groups. On d 1, 3, 7, 14, 21, 28, and 35, twelve birds from each group were randomly selected for slaughter and post-slaughter analysis. The results showed that BW of pigeons increased rapidly from d 1 to d 28 (a 25.7-fold increase), and then had little change until d 35. The Logistic, Gompertz, and Von Bertalanffy functions can all be well fitted with the growth curve of domestic pigeons (R2>0.90) and the Gompertz model showed the highest R2value among the models (R2=0.9997). The equation of Gompertz model was Y=507.72×e-(3.76exp(-0.17t))(Y=BW of pigeon (g); t=time (day)). In addition, breast meat yield (%) increased with age throughout the experiment, whereas the leg meat yield (%) reached to the peak on d 14. Serum total protein, albumin, globulin, and glucose concentration were increased with age, whereas serum uric acid concentration was decreased (P<0.05). Furthermore, the gene expressions of nutrient transporters (y+LAT2, LAT1, B0AT1, PepT1, and NHE2) in jejunum of pigeon were increased with age. The results of correlation analysis showed the gene expressions of B0AT1, PepT1, and NHE2 had positive correlations with BW (0.73

  20. Eplerenone ameliorates the phenotypes of metabolic syndrome with NASH in liver-specific SREBP-1c Tg mice fed high-fat and high-fructose diet.

    PubMed

    Wada, Tsutomu; Miyashita, Yusuke; Sasaki, Motohiro; Aruga, Yusuke; Nakamura, Yuto; Ishii, Yoko; Sasahara, Masakiyo; Kanasaki, Keizo; Kitada, Munehiro; Koya, Daisuke; Shimano, Hitoshi; Tsuneki, Hiroshi; Sasaoka, Toshiyasu

    2013-12-01

    Because the renin-angiotensin-aldosterone system has been implicated in the development of insulin resistance and promotion of fibrosis in some tissues, such as the vasculature, we examined the effect of eplerenone, a selective mineralocorticoid receptor (MR) antagonist, on nonalcoholic steatohepatitis (NASH) and metabolic phenotypes in a mouse model reflecting metabolic syndrome in humans. We adopted liver-specific transgenic (Tg) mice overexpressing the active form of sterol response element binding protein-1c (SREBP-1c) fed a high-fat and fructose diet (HFFD) as the animal model in the present study. When wild-type (WT) C57BL/6 and liver-specific SREBP-1c Tg mice grew while being fed HFFD for 12 wk, body weight and epididymal fat weight increased in both groups with an elevation in blood pressure and dyslipidemia. Glucose intolerance and insulin resistance were also observed. Adipose tissue hypertrophy and macrophage infiltration with crown-like structure formation were also noted in mice fed HFFD. Interestingly, the changes noted in both genotypes fed HFFD were significantly ameliorated with eplerenone. HFFD-fed Tg mice exhibited the histological features of NASH in the liver, including macrovesicular steatosis and fibrosis, whereas HFFD-fed WT mice had hepatic steatosis without apparent fibrotic changes. Eplerenone effectively ameliorated these histological abnormalities. Moreover, the direct suppressive effects of eplerenone on lipopolysaccharide-induced TNFα production in the presence and absence of aldosterone were observed in primary-cultured Kupffer cells and bone marrow-derived macrophages. These results indicated that eplerenone prevented the development of NASH and metabolic abnormalities in mice by inhibiting inflammatory responses in both Kupffer cells and macrophages. PMID:24129399

  1. CHIP(-/-)-Mouse Liver: Adiponectin-AMPK-FOXO-Activation Overrides CYP2E1-Elicited JNK1-Activation, Delaying Onset of NASH: Therapeutic Implications.

    PubMed

    Kim, Sung-Mi; Grenert, James P; Patterson, Cam; Correia, Maria Almira

    2016-01-01

    Genetic ablation of C-terminus of Hsc70-interacting protein (CHIP) E3 ubiquitin-ligase impairs hepatic cytochrome P450 CYP2E1 degradation. Consequent CYP2E1 gain of function accelerates reactive O2 species (ROS) production, triggering oxidative/proteotoxic stress associated with sustained activation of c-Jun NH2-terminal kinase (JNK)-signaling cascades, pro-inflammatory effectors/cytokines, insulin resistance, progressive hepatocellular ballooning and microvesicular steatosis. Despite this, little evidence of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) was found in CHIP(-/-)-mice over the first 8-9-months of life. We herein document that this lack of tissue injury is largely due to the concurrent up-regulation and/or activation of the adiponectin-5'-AMP-activated protein kinase (AMPK)-forkhead box O (FOXO)-signaling axis stemming from at the least three synergistic features: Up-regulated expression of adipose tissue adiponectin and its hepatic adipoR1/adipoR2 receptors, stabilization of hepatic AMPKα1-isoform, identified herein for the first time as a CHIP-ubiquitination substrate (unlike its AMPKα2-isoform), as well as nuclear stabilization of FOXOs, well-known CHIP-ubiquitination targets. Such beneficial predominance of the adiponectin-AMPK-FOXO-signaling axis over the sustained JNK-elevation and injurious insulin resistance in CHIP(-/-)-livers apparently counteracts/delays rapid progression of the hepatic microvesicular steatosis to the characteristic macrovesicular steatosis observed in clinical NASH and/or rodent NASH-models. PMID:27406999

  2. CHIP−/−-Mouse Liver: Adiponectin-AMPK-FOXO-Activation Overrides CYP2E1-Elicited JNK1-Activation, Delaying Onset of NASH: Therapeutic Implications

    PubMed Central

    Kim, Sung-Mi; Grenert, James P.; Patterson, Cam; Correia, Maria Almira

    2016-01-01

    Genetic ablation of C-terminus of Hsc70-interacting protein (CHIP) E3 ubiquitin-ligase impairs hepatic cytochrome P450 CYP2E1 degradation. Consequent CYP2E1 gain of function accelerates reactive O2 species (ROS) production, triggering oxidative/proteotoxic stress associated with sustained activation of c-Jun NH2-terminal kinase (JNK)-signaling cascades, pro-inflammatory effectors/cytokines, insulin resistance, progressive hepatocellular ballooning and microvesicular steatosis. Despite this, little evidence of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) was found in CHIP−/−-mice over the first 8–9-months of life. We herein document that this lack of tissue injury is largely due to the concurrent up-regulation and/or activation of the adiponectin-5′-AMP-activated protein kinase (AMPK)-forkhead box O (FOXO)-signaling axis stemming from at the least three synergistic features: Up-regulated expression of adipose tissue adiponectin and its hepatic adipoR1/adipoR2 receptors, stabilization of hepatic AMPKα1-isoform, identified herein for the first time as a CHIP-ubiquitination substrate (unlike its AMPKα2-isoform), as well as nuclear stabilization of FOXOs, well-known CHIP-ubiquitination targets. Such beneficial predominance of the adiponectin-AMPK-FOXO-signaling axis over the sustained JNK-elevation and injurious insulin resistance in CHIP−/−-livers apparently counteracts/delays rapid progression of the hepatic microvesicular steatosis to the characteristic macrovesicular steatosis observed in clinical NASH and/or rodent NASH-models. PMID:27406999

  3. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico, Class III

    SciTech Connect

    Murphy, Mark B.

    2000-10-25

    The Nash Draw Brushy Canyon Pool (NDP) is southeast New Mexico is one of the nine projects selected in 1995 by the U.S. Department of Energy (DOE) for participation in the Class III Reservoir Field Demonstration Program. The goals of the DOE cost-shared Class Program are to: (1) extend economic production, (2) increase ultimate recovery, and (3) broaden information exchange and technology application. Reservoirs in the Class III Program are focused on slope-basin and deep-basin clastic depositional types.

  4. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico

    SciTech Connect

    Murphy, Mark B.

    1999-11-01

    The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  5. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico, Class III

    SciTech Connect

    Murphy, Michael B.

    2002-02-21

    The overall objective of this project is to demonstrate that a development program based on advanced reservoir management methods can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  6. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico, Class III

    SciTech Connect

    Murphy, Mark B.

    2002-01-16

    The overall objective of this project was to demonstrate that a development program-based on advanced reservoir management methods-can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan included developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals were (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the U.S. oil and gas industry.

  7. A Logical Approach to Entanglement

    NASA Astrophysics Data System (ADS)

    Das, Abhishek

    2016-05-01

    In this paper we innovate a logical approach to develop an intuition regarding the phenomenon of quantum entanglement. In the vein of the logic introduced we substantiate that particles that were entangled in the past will be entangled in perpetuity and thereby abide a rule that restricts them to act otherwise. We also introduce a game and by virtue of the concept of Nash equilibrium we have been able to show that entangled particles will mutually correspond to an experiment that is performed on any one of the particle.

  8. Advanced Oil Recovery Technologies for Improve Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool,Eddy County,NM

    SciTech Connect

    Murphy, M.B.

    1997-10-31

    The Nash Draw Brushy Canyon Pool in Eddy County New Mexico is a field demonstration in the U. S. Department of Energy Class IH Program. Advanced reservoir characterization techniques are being used at the Nash Draw project to develop reservoir management strategies for optimizing oil recovery from this Delaware reservoir. Analysis, interpretation, and integration of recently acquired geological, geophysical, and engineering data revealed that the initial reservoir description was too simplistic to capture the critical features of this complex formation. As a result of the analysis, a proposed pilot area was reconsidered. Comparison of seismic data and engineering data have shown evidence of discontinuities in the area surrounding the proposed injector. Analysis of the 3-D seismic has shown that wells in the proposed pilot are in an area of poor quality amplitude development. The implication is that since amplitude attenuation is a function of porosity, then this is not the best area to be attempting a pilot pressure maintenance project. Because the original pilot area appears to be compartmentalized, the lateral continuity between the pilot wells could be reduced. The 3-D seismic interpretation indicates other areas may be better suited for the initial pilot area. Therefore, the current focus has shifted more to targeted drilling, and the pilot injection will be considered in a more continuous area of the NDP in the future. Results of reservoir simulation studies indicate that pressure maintenance should be started early when reservoir pressure is still high.

  9. Conditioned discrimination of magnetic inclination in a spatial-orientation arena task by homing pigeons (Columba livia).

    PubMed

    Mora, Cordula V; Acerbi, Merissa L; Bingman, Verner P

    2014-12-01

    It has been well established that homing pigeons are able to use the Earth's magnetic field to obtain directional information when returning to their loft and that their magnetic compass is based, at least in part, on the perception of magnetic inclination. Magnetic inclination has also been hypothesized in pigeons and other long-distance navigators, such as sea turtles, to play a role providing positional information as part of a map. Here we developed a behavioral paradigm which allows us to condition homing pigeons to discriminate magnetic inclination cues in a spatial-orientation arena task. Six homing pigeons were required to discriminate in a circular arena between feeders located either in a zone with a close to 0 deg inclination cue or in a zone with a rapidly changing inclination cue (-3 deg to +85 deg when approaching the feeder and +85 deg to -3 deg when moving away from the feeder) to obtain a food reward. The pigeons consistently performed this task above chance level. Control experiments, during which the coils were turned off or the current was running anti-parallel through the double-wound coil system, confirmed that no alternative cues were used by the birds in the discrimination task. The results show that homing pigeons can be conditioned to discriminate differences in magnetic field inclination, enabling investigation into the peripheral and central neural processing of geomagnetic inclination under controlled laboratory conditions. PMID:25278470

  10. High-performance liquid chromatography determination of N- and O-demethylase activities of chemicals in human liver microsomes: application of postcolumn fluorescence derivatization using Nash reagent.

    PubMed

    Kobayashi, K; Yamamoto, T; Taguchi, M; Chiba, K

    2000-09-10

    Formaldehyde is liberated in the process of cytochrome P450 (CYP) mediated demethylation of a wide variety of compounds containing the CH(3)N or CH(3)O functionality. A highly sensitive method using a high-performance liquid chromatography (HPLC) system with postcolumn derivatization was developed to measure the liberated formaldehyde as N- and O-demethylase activity of drugs in human liver microsomes. Following the chromatographic separation of formaldehyde on a C18 column, the formaldehyde was reacted with the Nash reagent in the postcolumn reactor at 100 degrees C and detected by the fluorescence method. The results showed that the present method has excellent precision and accuracy. The intra- and interassay variances of this method were less than 10%. The newly developed HPLC method was found to be about 80-fold more sensitive than the colorimetric method in detection of formaldehyde. The N-demethylase activity of sertraline in rat liver microsomes determined by the present method did not differ from those detected by previous methods quantifying produced desmethyl metabolite. The present method has been successfully applied to determine the N-demethylase activities of several drugs, including aminopyrine, erythromycin, fluoxetine, S-mephenytoin, and sertraline, in human liver microsomes. This assay should be useful for generic analysis of N- and O-demethylase activities of xenobiotic and endobiotic chemicals by CYP enzymes. PMID:10964418

  11. Advanced oil recovery technologies for improved recovery from slope basin clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico. Annual report, September 25, 1995--September 24, 1996

    SciTech Connect

    Murphy, M.B.

    1997-08-01

    The basic driver for this project is the low recovery observed in Delaware reservoirs, such as the Nash Draw Pool (NDP). This low recovery is caused by low reservoir energy, less than optimum permeabilities and porosities, and inadequate reservoir characterization and reservoir management strategies which are typical of projects operated by independent producers. Rapid oil decline rates and high gas/oil ratios are typically observed in the first year of primary production. Based on the production characteristics that have been observed in similar Delaware fields, pressure maintenance is a likely requirement at the Nash Pool. Three basic constraints to producing the Nash Draw Brushy Canyon Reservoir are: (1) limited areal and interwell geologic knowledge, (2) lack of an engineering tool to evaluate the various producing strategies, and (3) limited surface access prohibiting development with conventional drilling. The limited surface access is caused by the proximity of underground potash mining and surface playa lakes. The objectives of this project are: (1) to demonstrate that a development drilling program and pressure maintenance program, based on advanced reservoir management methods, can significantly improve oil recovery compared with existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers, especially in the Permian Basin.

  12. Efficacy of nicarbazin (Ovistop®) in the containment and reduction of the populations of feral pigeons (Columba livia var. domestica) in the city of Genoa, Italy: a retrospective evaluation.

    PubMed

    Albonetti, Paolo; Marletta, Antonio; Repetto, Ivano; Sasso, Emanuela Assunta

    2015-01-01

    This study describes the results of a retrospective evaluation (8 years: 2005-2012) of the efficacy of the anti-fertility drug, Ovistop® nicarbazin (800 ppm) added to corn kernels used to feed non-migratory feral pigeon colonies, Columba livia var. domestica, in the city of Genoa, Italy. The observation interested 4 non-migratory feral pigeon colonies located into well‑defined areas of the city of Genoa, Italy. Three of these colonies were treated for 12 months, with 10 g of drug (Ovistop®) provided per bird per day for 5 days each week; the other colony was treated in the same way but with a placebo (control station). Each colony and the relative area where the colony was located were both monitored with the same daily examination. Statistical analysis techniques were applied to the findings recorded - both descriptive (indices of central and dispersion trends) and comparative (one-way variance analysis). In the colonies treated with the drug, following an initial increase in the population ('magnet effect'), a reduction was observed over the following 4 years (-35% >x> -45%) and a further decrease (-65% >x> -70%) was observed over the subsequent 4 years (statistically significant one-way ANOVA p<0.01). This phenomenon was recorded across the board in the 3 treated stations, compared to the overall unstable trend observed for the control station. As no external or exceptional anthropic or natural factors were observed, it can be stated that, given the results observed, the drug seemed effective in reducing the treated bird populations. PMID:25842215

  13. Anisotropic and heterogeneous mechanical properties of a stratified shale/limestone sequence at Nash Point, South Wales: A case study for hydraulic fracture propagation through a layered medium

    NASA Astrophysics Data System (ADS)

    Forbes Inskip, Nathaniel; Meredith, Philip; Gudmundsson, Agust

    2016-04-01

    While considerable effort has been expended on the study of fracture propagation in rocks in recent years, our understanding of how fractures propagate through layered sedimentary rocks with different mechanical and elastic properties remains poorly constrained. Yet this is a key issue controlling the propagation of both natural and anthropogenic hydraulic fractures in layered sequences. Here we report measurements of the contrasting mechanical and elastic properties of the Lower Lias at Nash Point, South Wales, which comprises an interbedded sequence of shale and limestone layers, and how those properties may influence fracture propagation. Elastic properties of both materials have been characterised via ultrasonic wave velocity measurements as a function of azimuth on samples cored both normal and parallel to bedding. The shale is highly anisotropic, with P-wave velocities varying from 2231 to 3890 m s-1, giving an anisotropy of ~55%. By contrast, the limestone is essentially isotropic, with a mean P-wave velocity of 5828 m s-1 and an anisotropy of ~2%. The dynamic Young's modulus of the shale, calculated from P- and S-wave velocity data, is also anisotropic with a value of 36 GPa parallel to bedding and 12 GPa normal to bedding. The modulus of the limestone is again isotropic with a value of 80 GPa. It follows that for a vertical fracture propagating (i.e. normal to bedding) the modulus contrast is 6.6. This is important because the contrast in elastic properties is a key factor in controlling whether fractures arrest, deflect, or propagate across interfaces between layers in a sequence. There are three principal mechanisms by which a fracture may deflect across or along an interface, namely: Cook-Gordon debonding, stress barrier, and elastic mismatch. Preliminary numerical modelling results (using a Finite Element Modelling software) of induced fractures at Nash Point suggest that all three are important. The results demonstrate a rotation of the maximum

  14. Willie Mays: Meet John Nash.

    ERIC Educational Resources Information Center

    Merz, Thomas E.

    1996-01-01

    Uses the various strategies involved in baseball to illustrate basic concepts in game theory. Specifically discusses Willie Mays' base-stealing strategy and how it relates to probability and risk. Reminds students that expected results depend on adopted assumptions. (MJP)

  15. Advanced oil recovery technologies for improved recovery from slope basin clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, NM. Second annual technical progress report, October 1, 1996--September 30, 1997

    SciTech Connect

    1998-09-01

    The Nash Draw Brushy Canyon Pool in Eddy County, New Mexico is a field demonstration in the US Department of Energy Class III Program. Advanced reservoir characterization techniques are being used at the Nash Draw project to develop reservoir management strategies for optimizing oil recovery from this Delaware reservoir. Analysis, interpretation, and integration of recently acquired geological, geophysical, and engineering data revealed that the initial reservoir description was too simplistic to capture the critical features of this complex formation. As a result of the analysis, a proposed pilot area was reconsidered. Comparison of seismic data and engineering data have shown evidence of discontinuities in the area surrounding the proposed injector. Analysis of the 3-D seismic has shown that wells in the proposed pilot are in an area of poor quality amplitude development. The implication is that since amplitude attenuation is a function of porosity, then this is not the best area to be attempting a pilot pressure maintenance project. Because the original pilot area appears to be compartmentalized, the lateral continuity between the pilot wells could be reduced. The 3-D seismic interpretation indicates other areas may be better suited for the initial pilot area. Therefore, the current focus has shifted more to targeted drilling, and the pilot injection will be considered in a more continuous area of the NDP in the future. Results of reservoir simulation studies indicate that pressure maintenance should be started early when reservoir pressure is still high.

  16. Biomarkers of NAFLD progression: a lipidomics approach to an epidemic1[S

    PubMed Central

    Gorden, D. Lee; Myers, David S.; Ivanova, Pavlina T.; Fahy, Eoin; Maurya, Mano R.; Gupta, Shakti; Min, Jun; Spann, Nathanael J.; McDonald, Jeffrey G.; Kelly, Samuel L.; Duan, Jingjing; Sullards, M. Cameron; Leiker, Thomas J.; Barkley, Robert M.; Quehenberger, Oswald; Armando, Aaron M.; Milne, Stephen B.; Mathews, Thomas P.; Armstrong, Michelle D.; Li, Chijun; Melvin, Willie V.; Clements, Ronald H.; Washington, M. Kay; Mendonsa, Alisha M.; Witztum, Joseph L.; Guan, Ziqiang; Glass, Christopher K.; Murphy, Robert C.; Dennis, Edward A.; Merrill, Alfred H.; Russell, David W.; Subramaniam, Shankar; Brown, H. Alex

    2015-01-01

    The spectrum of nonalcoholic fatty liver disease (NAFLD) includes steatosis, nonalcoholic steatohepatitis (NASH), and cirrhosis. Recognition and timely diagnosis of these different stages, particularly NASH, is important for both potential reversibility and limitation of complications. Liver biopsy remains the clinical standard for definitive diagnosis. Diagnostic tools minimizing the need for invasive procedures or that add information to histologic data are important in novel management strategies for the growing epidemic of NAFLD. We describe an “omics” approach to detecting a reproducible signature of lipid metabolites, aqueous intracellular metabolites, SNPs, and mRNA transcripts in a double-blinded study of patients with different stages of NAFLD that involves profiling liver biopsies, plasma, and urine samples. Using linear discriminant analysis, a panel of 20 plasma metabolites that includes glycerophospholipids, sphingolipids, sterols, and various aqueous small molecular weight components involved in cellular metabolic pathways, can be used to differentiate between NASH and steatosis. This identification of differential biomolecular signatures has the potential to improve clinical diagnosis and facilitate therapeutic intervention of NAFLD. PMID:25598080

  17. Advanced oil recovery technologies for improved recovery from slope basin clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, NM. Quarterly technical progress report, January 1--March 31, 1998

    SciTech Connect

    1998-04-30

    The overall objective of this project is to demonstrate that a development program--based on advanced reservoir management methods--can significantly improve oil recovery at the Nash Draw Pool (NDP). The plan includes developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced reservoir management methods. Specific goals are (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers in the Permian Basin and elsewhere throughout the US oil and gas industry. Results obtained to date are summarized for the following: geostatistics and reservoir mapping; reservoir engineering; reservoir characterization/reservoir simulation; miscible recovery simulations; and technology transfer.

  18. State-level approaches to managing the use of contraceptives in wildlife in the United States.

    PubMed

    Eisemann, John D; O'Hare, Jeanette R; Fagerstone, Kathleen A

    2013-12-01

    Several fertility control agents have recently been registered with the U.S. Environmental Protection Agency for management of wildlife or other free-ranging animals. The registration of GonaCon Immunocontraceptive Vaccine for use in white-tailed deer (Odocoileus virginianus) and OvoControl for use in Canada geese (Branta canadensis) and pigeons (Columba livia) has caused state wildlife and land management agencies to review their regulatory authority over the use of contraceptives in wildlife. As a result, many states are taking steps to ensure legislation or policies are current with emerging technologies. This article examines the various approaches states are taking to regulate the use of contraceptives. Regardless of the final regulatory approach, biological, social, economic, and political implications must all be discussed as this new tool is introduced into the field of ona wildlife management. Thoughtful consideration of all aspects of wildlife contraceptive use will lead to the development of sound, best management practices for current and future products. PMID:24437085

  19. Spatial context learning in pigeons (Columba livia).

    PubMed

    Gibson, Brett M; Leber, Andrew B; Mehlman, Max L

    2015-10-01

    In a seminal paper in the cognitive sciences, Chun and Jiang (1998) described the contextual cueing paradigm in which they used artificial stimuli and showed that people became faster to locate a target when the background predicted the location of a target compared to when it did not. Here we examined contextual cueing in pigeons for the first time using artificial stimuli and procedures similar to those of Chun and Jiang. In the first test, we had pigeons search for a target among a display of seven distractors; during one condition, the position of the distractors predicted the location of the target, and in the second condition, there was no relationship between the two. In a second test, we presented the pigeons with the predictive displays from Test 1 and a second set of displays that also predicted the location of a target to see if learning about one set of predictive backgrounds disrupted learning about a second set. The pigeons were quick to acquire context-based knowledge and retain that information when faced with additional contexts. The results suggest that contextual cueing can occur for a variety of stimuli in nonhuman animals and that it may be a common mechanism for processing visual information across a wide variety of species. PMID:26167773

  20. Regulatory drinking in the pigeon Columba livia.

    PubMed

    Kaufman, S; Peters, G

    1980-09-01

    Pigeons were subjected to stimuli known to induce regulatory drinking in mammals. Water-satiated birds drank in response to intravenous (iv) hypertonic NaCl, intraperitoneal (ip) hyperoncotic polyethylene glycol (PEG) (20 M), iv infusions of angiotensinamide, subcutaneous (sc) isoprenaline, and iv chicken kidney extract. Intravenous porcine renin failed to elicit a major drinking response. Drinking after water deprivation was reduced by an iv preload of isotonic saline. Water intake after iv hypertonic NaCl equaled the volume required for dilution to isotonicity. Water intake in response to ip PEG was larger than in rats and resulted in a parallel increase in body weight. Sensitivity to isoprenaline and angiotensinamide was less than or equal to that of rats although pigeons drank much more. Drinking responses to iv hypertonic NaCl plus ip hyperoncotic PEG were additive. Small (5 ml/kg body wt) blood losses induced delayed (after 4 h) drinking; larger blood losses were ineffective. There was no simple additive relationship between the responses to hemorrhage and hypertonic saline. In summary, the dipsogenic response of pigeons was much greater than that of mammals although sensitivity was sometimes higher and sometimes lower. PMID:7435592

  1. Dietary approach in the treatment of nonalcoholic fatty liver disease

    PubMed Central

    Ferolla, Silvia Marinho; Silva, Luciana Costa; Ferrari, Maria de Lourdes Abreu; da Cunha, Aloísio Sales; Martins, Flaviano dos Santos; Couto, Cláudia Alves; Ferrari, Teresa Cristina Abreu

    2015-01-01

    Nonalcoholic fatty liver disease (NAFLD) has been identified as one of the most prevalent chronic liver disease in adults and children populations. NAFLD is usually associated with the metabolic syndrome (MS), which is chiefly related to insulin resistance and its consequences. Insulin resistance has a crucial role in the pathogenesis of hepatic steatosis and potentially nonalcoholic steatohepatitis (NASH). Because of the contemporary epidemics of MS and obesity, the burden of NAFLD is also expected to rise. Unhealthy diets, such as the so-called western diet, are enriched in fructose, trans-fatty acids and saturated fat and seem to be associated with the development of NAFLD. In human studies, certain dietary sugars, particularly fructose, are used as a substrate for lipogenesis leading to hepatic fatty infiltration, inflammation, and possibly fibrosis. Other investigations have shown that fat consumption especially cholesterol and trans/saturated fatty acids are also steatogenic and seem to increase visceral adiposity. The identification of specific dietary components that favor the development of NASH could be important for the management of this disorder. This review focuses on the effects of different dietary approaches to prevent and treat NAFLD emphasizing the macronutrients and energy composition. PMID:26523205

  2. Dietary approach in the treatment of nonalcoholic fatty liver disease.

    PubMed

    Ferolla, Silvia Marinho; Silva, Luciana Costa; Ferrari, Maria de Lourdes Abreu; da Cunha, Aloísio Sales; Martins, Flaviano Dos Santos; Couto, Cláudia Alves; Ferrari, Teresa Cristina Abreu

    2015-10-28

    Nonalcoholic fatty liver disease (NAFLD) has been identified as one of the most prevalent chronic liver disease in adults and children populations. NAFLD is usually associated with the metabolic syndrome (MS), which is chiefly related to insulin resistance and its consequences. Insulin resistance has a crucial role in the pathogenesis of hepatic steatosis and potentially nonalcoholic steatohepatitis (NASH). Because of the contemporary epidemics of MS and obesity, the burden of NAFLD is also expected to rise. Unhealthy diets, such as the so-called western diet, are enriched in fructose, trans-fatty acids and saturated fat and seem to be associated with the development of NAFLD. In human studies, certain dietary sugars, particularly fructose, are used as a substrate for lipogenesis leading to hepatic fatty infiltration, inflammation, and possibly fibrosis. Other investigations have shown that fat consumption especially cholesterol and trans/saturated fatty acids are also steatogenic and seem to increase visceral adiposity. The identification of specific dietary components that favor the development of NASH could be important for the management of this disorder. This review focuses on the effects of different dietary approaches to prevent and treat NAFLD emphasizing the macronutrients and energy composition. PMID:26523205

  3. J.B. Nash Lecture Series.

    ERIC Educational Resources Information Center

    Gray, Howard R., Comp.; And Others

    The following lectures are presented in this publication: (1) "The Dynamics of Recreation" (Betty Van der Smissen); (2) "Recreation Prospects" (Edith L. Ball); (3) "A View of the Past--A Bridge to the Future" (Allen V. Sapora); (4) "Coming to Grips with the New Leisure" (Richard G. Kraus); (5) "The Mild Blue Yonder--Changing Lifestyles and…

  4. Role of Hedgehog Signaling Pathway in NASH.

    PubMed

    Verdelho Machado, Mariana; Diehl, Anna Mae

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) is the number one cause of chronic liver disease in the Western world. Although only a minority of patients will ultimately develop end-stage liver disease, it is not yet possible to efficiently predict who will progress and, most importantly, effective treatments are still unavailable. Better understanding of the pathophysiology of this disease is necessary to improve the clinical management of NAFLD patients. Epidemiological data indicate that NAFLD prognosis is determined by an individual's response to lipotoxic injury, rather than either the severity of exposure to lipotoxins, or the intensity of liver injury. The liver responds to injury with a synchronized wound-healing response. When this response is abnormal, it leads to pathological scarring, resulting in progressive fibrosis and cirrhosis, rather than repair. The hedgehog pathway is a crucial player in the wound-healing response. In this review, we summarize the pre-clinical and clinical evidence, which demonstrate the role of hedgehog pathway dysregulation in NAFLD pathogenesis, and the preliminary data that place the hedgehog pathway as a potential target for the treatment of this disease. PMID:27258259

  5. Role of Hedgehog Signaling Pathway in NASH

    PubMed Central

    Verdelho Machado, Mariana; Diehl, Anna Mae

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) is the number one cause of chronic liver disease in the Western world. Although only a minority of patients will ultimately develop end-stage liver disease, it is not yet possible to efficiently predict who will progress and, most importantly, effective treatments are still unavailable. Better understanding of the pathophysiology of this disease is necessary to improve the clinical management of NAFLD patients. Epidemiological data indicate that NAFLD prognosis is determined by an individual’s response to lipotoxic injury, rather than either the severity of exposure to lipotoxins, or the intensity of liver injury. The liver responds to injury with a synchronized wound-healing response. When this response is abnormal, it leads to pathological scarring, resulting in progressive fibrosis and cirrhosis, rather than repair. The hedgehog pathway is a crucial player in the wound-healing response. In this review, we summarize the pre-clinical and clinical evidence, which demonstrate the role of hedgehog pathway dysregulation in NAFLD pathogenesis, and the preliminary data that place the hedgehog pathway as a potential target for the treatment of this disease. PMID:27258259

  6. Different approaches for centralized and decentralized water system management in multiple decision makers' problems

    NASA Astrophysics Data System (ADS)

    Anghileri, D.; Giuliani, M.; Castelletti, A.

    2012-04-01

    There is a general agreement that one of the most challenging issues related to water system management is the presence of many and often conflicting interests as well as the presence of several and independent decision makers. The traditional approach to multi-objective water systems management is a centralized management, in which an ideal central regulator coordinates the operation of the whole system, exploiting all the available information and balancing all the operating objectives. Although this approach allows to obtain Pareto-optimal solutions representing the maximum achievable benefit, it is based on assumptions which strongly limits its application in real world contexts: 1) top-down management, 2) existence of a central regulation institution, 3) complete information exchange within the system, 4) perfect economic efficiency. A bottom-up decentralized approach seems therefore to be more suitable for real case applications since different reservoir operators may maintain their independence. In this work we tested the consequences of a change in the water management approach moving from a centralized toward a decentralized one. In particular we compared three different cases: the centralized management approach, the independent management approach where each reservoir operator takes the daily release decision maximizing (or minimizing) his operating objective independently from each other, and an intermediate approach, leading to the Nash equilibrium of the associated game, where different reservoir operators try to model the behaviours of the other operators. The three approaches are demonstrated using a test case-study composed of two reservoirs regulated for the minimization of flooding in different locations. The operating policies are computed by solving one single multi-objective optimal control problem, in the centralized management approach; multiple single-objective optimization problems, i.e. one for each operator, in the independent case

  7. Wavelet-based multiscale performance analysis: An approach to assess and improve hydrological models

    NASA Astrophysics Data System (ADS)

    Rathinasamy, Maheswaran; Khosa, Rakesh; Adamowski, Jan; ch, Sudheer; Partheepan, G.; Anand, Jatin; Narsimlu, Boini

    2014-12-01

    The temporal dynamics of hydrological processes are spread across different time scales and, as such, the performance of hydrological models cannot be estimated reliably from global performance measures that assign a single number to the fit of a simulated time series to an observed reference series. Accordingly, it is important to analyze model performance at different time scales. Wavelets have been used extensively in the area of hydrological modeling for multiscale analysis, and have been shown to be very reliable and useful in understanding dynamics across time scales and as these evolve in time. In this paper, a wavelet-based multiscale performance measure for hydrological models is proposed and tested (i.e., Multiscale Nash-Sutcliffe Criteria and Multiscale Normalized Root Mean Square Error). The main advantage of this method is that it provides a quantitative measure of model performance across different time scales. In the proposed approach, model and observed time series are decomposed using the Discrete Wavelet Transform (known as the à trous wavelet transform), and performance measures of the model are obtained at each time scale. The applicability of the proposed method was explored using various case studies--both real as well as synthetic. The synthetic case studies included various kinds of errors (e.g., timing error, under and over prediction of high and low flows) in outputs from a hydrologic model. The real time case studies investigated in this study included simulation results of both the process-based Soil Water Assessment Tool (SWAT) model, as well as statistical models, namely the Coupled Wavelet-Volterra (WVC), Artificial Neural Network (ANN), and Auto Regressive Moving Average (ARMA) methods. For the SWAT model, data from Wainganga and Sind Basin (India) were used, while for the Wavelet Volterra, ANN and ARMA models, data from the Cauvery River Basin (India) and Fraser River (Canada) were used. The study also explored the effect of the

  8. Crowd Computing as a Cooperation Problem: An Evolutionary Approach

    NASA Astrophysics Data System (ADS)

    Christoforou, Evgenia; Fernández Anta, Antonio; Georgiou, Chryssis; Mosteiro, Miguel A.; Sánchez, Angel

    2013-05-01

    Cooperation is one of the socio-economic issues that has received more attention from the physics community. The problem has been mostly considered by studying games such as the Prisoner's Dilemma or the Public Goods Game. Here, we take a step forward by studying cooperation in the context of crowd computing. We introduce a model loosely based on Principal-agent theory in which people (workers) contribute to the solution of a distributed problem by computing answers and reporting to the problem proposer (master). To go beyond classical approaches involving the concept of Nash equilibrium, we work on an evolutionary framework in which both the master and the workers update their behavior through reinforcement learning. Using a Markov chain approach, we show theoretically that under certain----not very restrictive—conditions, the master can ensure the reliability of the answer resulting of the process. Then, we study the model by numerical simulations, finding that convergence, meaning that the system reaches a point in which it always produces reliable answers, may in general be much faster than the upper bounds given by the theoretical calculation. We also discuss the effects of the master's level of tolerance to defectors, about which the theory does not provide information. The discussion shows that the system works even with very large tolerances. We conclude with a discussion of our results and possible directions to carry this research further.

  9. Current concepts and management approaches in nonalcoholic fatty liver disease.

    PubMed

    Attar, Bashar M; Van Thiel, David H

    2013-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver dysfunction worldwide. NAFLD may progress to nonalcoholic steatohepatitis (NASH) and in turn cirrhosis. Importantly, hepatic cancer can occur in NASH in the absence of cirrhosis. The cardinal histologic feature of NAFLD is the presence of an excessive accumulation of triacylglycerols and diacylglycerols in hepatocytes. The presence of obesity and insulin resistance lead to an increased hepatic-free fatty acid (FFA) flux creating an environment appropriate for the development of NAFLD. The generation of toxic reactive oxygen species with the production of hepatic injury and inflammation as a consequence of FFA oxidation will ultimately lead to the initiation and progression of fibrosis. Lifestyle modifications specifically weight loss, physical exercise, and cognitive behavior therapy have been recommended as treatments for NASH. Dietary fructose is an independent risk factor for the development of NAFLD. Pioglitazone can be used to treat biopsy-proven NASH; however, its safety risks should be considered carefully. Greater consumption for coffee, independent of its caffeine component, has been associated with a significant reduced risk of advanced fibrosis in NASH. Additional data are needed before recommending bariatric surgery as an established option for the specific treatment of NASH. PMID:23576902

  10. Detection and discrimination of complex sounds by pigeons (Columba livia).

    PubMed

    Cook, Robert G; Qadri, Muhammad A J; Oliveira, Ryan

    2016-02-01

    Auditory scene analysis is the process by which sounds are separated and identified from each other and from the background to make functional auditory objects. One challenge in making these psychological units is that complex sounds often continuously differ in composition over their duration. Here we examined the acoustic basis of complex sound processing in four pigeons by evaluating their performance in an ongoing same/different (S/D) task. This provided an opportunity to investigate avian auditory processing in a non-vocal learning, non-songbird. These pigeons were already successfully discriminating 18.5 s sequences of all different 1.5 s sounds (ABCD…) from sequences of one sound repeating (AAAA…, BBBB…, etc.) in a go/no-go procedure. The stimuli for these same/different sequences consisted of 504 tonal sounds (36 chromatic notes×14 different instruments), 36 pure tones, and 72 complex sounds. Not all of these sounds were equally effective in supporting S/D discrimination. As identified by a stepwise regression modeling of ten acoustic properties, tonal and complex sounds with intermediate levels of acoustic content tended to support better discrimination. The results suggest that pigeons have the auditory and cognitive capabilities to recognize and group continuously changing sound elements into larger functional units that can serve to differentiate long sequences of same and different sounds. PMID:26616672

  11. Efferent projections of the ectostriatum in the pigeon (Columba livia)

    NASA Technical Reports Server (NTRS)

    Husband, S. A.; Shimizu, T.

    1999-01-01

    The ectostriatum is a major visual component of the avian telencephalon. The core region of the ectostriatum (Ec) receives visual input from the optic tectum through thalamic nuclei. In the present study, the efferent projections of the ectostriatum were investigated by using the anterograde tracers Phaseolus vulgaris leucoagglutinin and biotinylated dextran amine. Projection patterns resulting from these tracers were confirmed by the retrograde tracer cholera toxin subunit B. When anterograde tracers were injected in Ec, primary projections were seen traveling dorsolaterally to the belt region of the ectostriatum (Ep) and the neostriatal area immediately surrounding Ep (Ep2). Neurons in Ep sent projections primarily to the overlying Ep2. The efferents of Ep2 traveled dorsolaterally to terminate in three telencephalic regions, from anterior to posterior: (1) neostriatum frontale, pars lateralis (NFL), (2) area temporo-parieto-occipitalis (TPO), and (3) neostriatum intermedium, pars lateralis (NIL). A part of the archistriatum intermedium and the lateral part of the neostriatum caudale also received somewhat minor projections. In addition, some neurons in Ec were also the source of direct, but minor, projections to the NFL, TPO, NIL, and archistriatum intermedium. The topographical relationship among the primary (Ec), secondary (Ep and Ep2), and tertiary (NFL, TPO, NIL) areas indicate that the neural populations for visual processing are organized along the rostral-caudal axis. Thus, the anterior Ec sent efferents to the anterior Ep, which in turn sent projections to anterior Ep2. Neurons in the anterior Ep2 sent projections to NFL and the anterior TPO. Similarly, the intermediate and posterior Ec sent projections to corresponding parts of Ep, whose efferents projected to intermediate and posterior Ep2, respectively. The intermediate Ep2 gave rise to major projections to TPO, whereas posterior Ep2 neurons sent efferents primarily to NIL. The organization of this neural circuit is compared with those of other sensory circuits in the avian telencephalon, as well as the laminar arrangement of the mammalian isocortex.

  12. Multiple cue use and integration in pigeons (Columba livia).

    PubMed

    Legge, Eric L G; Madan, Christopher R; Spetch, Marcia L; Ludvig, Elliot A

    2016-05-01

    Encoding multiple cues can improve the accuracy and reliability of navigation and goal localization. Problems may arise, however, if one cue is displaced and provides information which conflicts with other cues. Here we investigated how pigeons cope with cue conflict by training them to locate a goal relative to two landmarks and then varying the amount of conflict between the landmarks. When the amount of conflict was small, pigeons tended to integrate both cues in their search patterns. When the amount of conflict was large, however, pigeons used information from both cues independently. This context-dependent strategy for resolving spatial cue conflict agrees with Bayes optimal calculations for using information from multiple sources. PMID:26908004

  13. The pigeon (Columba livia) model of spontaneous atherosclerosis

    PubMed Central

    Anderson, J. L.; Smith, S. C.; Taylor, R. L.

    2014-01-01

    Multiple animal models have been employed to study human atherosclerosis, the principal cause of mortality in the United States. Each model has individual advantages related to specific pathologies. Initiation, the earliest disease phase, is best modeled by the White Carneau (WC-As) pigeon. Atherosclerosis develops spontaneously in the WC-As without either external manipulation or known risk factors. Furthermore, susceptibility is caused by a single gene defect inherited in an autosomal recessive manner. The Show Racer (SR-Ar) pigeon is resistant to atherosclerosis. Breed differences in the biochemistry and metabolism of celiac foci cells have been described. For example, WC-As have lower oxidative metabolism but higher amounts of chondroitin-6-sulfate and nonesterified fatty acids compared with SR-Ar. Gene expression in aortic smooth muscle cells was compared between breeds using representational difference analysis and microarray analysis. Energy metabolism and cellular phenotype were the chief gene expression differences. Glycolysis and synthetic cell types were related to the WC-As but oxidative metabolism and contractile cell types were related to the SR-Ar. Rosiglitazone, a PPARγ agonist, blocked RNA binding motif (RBMS1) expression in WC-As cells. The drug may act through the c-myc oncogene as RBMS1 is a c-myc target. Proteomic tests of aortic smooth muscle cells supported greater glycosylation in the WC-As and a transforming growth factor β effect in SR-Ar. Unoxidized fatty acids build up in WC-As cells because of their metabolic deficiency, ultimately preventing the contractile phenotype in these cells. The single gene responsible for the disease is likely regulatory in nature. PMID:25214557

  14. Bayesian Analysis of Foraging by Pigeons (Columba livia)

    PubMed Central

    Killeen, Peter R.; Palombo, Gina-Marie; Gottlob, Lawrence R.; Beam, Jon

    2008-01-01

    In this article, the authors combine models of timing and Bayesian revision of information concerning patch quality to predict foraging behavior. Pigeons earned food by pecking on 2 keys (patches) in an experimental chamber. Food was primed for only 1 of the patches on each trial. There was a constant probability of finding food in a primed patch, but it accumulated only while the animals searched there. The optimal strategy was to choose the better patch first and remain for a fixed duration, thereafter alternating evenly between the patches. Pigeons were nonoptimal in 3 ways: (a) they departed too early, (b) their departure times were variable, and (c) they were biased in their choices after initial departure. The authors review various explanations of these data. PMID:8865614

  15. Investigating causes of changes in runoff using hydrological simulation approach

    NASA Astrophysics Data System (ADS)

    Wang, Guoqing; Zhang, Jianyun; Li, Xuemei; Bao, Zhenxin; Liu, Yanli; Liu, Cuishan; He, Ruimin; Luo, Junsong

    2016-03-01

    Stream flow plays a crucial role in environmental, social and economic contexts. It is of significance to investigate the causes of change in runoff for better water resources management. This study detects the variation trend of recorded runoff of the Gushan River, a tributary of the Yellow River located on the Loess Plateau with severe soil and water losing, and investigates the impacts of climate change and human activities on runoff using hydrological simulation approach. Results show that the recorded runoff at Gaoshiya station on the Gushan River has experienced a significant declining trend from 1954-2013 with an abrupt change occurring in 1973. SimHyd rainfall runoff model performs well for monthly discharge simulation with Nash-Sutcliffe coefficient of 82.6 % and relative error of 0.32 %. Runoff depth over the catchment in 1980-2013 reduced by 52.4 mm compared to the previous period, in which human activities and climate change contribute 61.5 and 38.5 % of the total runoff reduction, respectively. However, the human-induced impact tends to increase. Therefore, efforts to improve the ecology of the Loess Plateau should give sufficient attention to the impacts of human activity.

  16. Intelligent cognitive radio jamming - a game-theoretical approach

    NASA Astrophysics Data System (ADS)

    Dabcevic, Kresimir; Betancourt, Alejandro; Marcenaro, Lucio; Regazzoni, Carlo S.

    2014-12-01

    Cognitive radio (CR) promises to be a solution for the spectrum underutilization problems. However, security issues pertaining to cognitive radio technology are still an understudied topic. One of the prevailing such issues are intelligent radio frequency (RF) jamming attacks, where adversaries are able to exploit on-the-fly reconfigurability potentials and learning mechanisms of cognitive radios in order to devise and deploy advanced jamming tactics. In this paper, we use a game-theoretical approach to analyze jamming/anti-jamming behavior between cognitive radio systems. A non-zero-sum game with incomplete information on an opponent's strategy and payoff is modelled as an extension of Markov decision process (MDP). Learning algorithms based on adaptive payoff play and fictitious play are considered. A combination of frequency hopping and power alteration is deployed as an anti-jamming scheme. A real-life software-defined radio (SDR) platform is used in order to perform measurements useful for quantifying the jamming impacts, as well as to infer relevant hardware-related properties. Results of these measurements are then used as parameters for the modelled jamming/anti-jamming game and are compared to the Nash equilibrium of the game. Simulation results indicate, among other, the benefit provided to the jammer when it is employed with the spectrum sensing algorithm in proactive frequency hopping and power alteration schemes.

  17. Approachability & Visibility

    ERIC Educational Resources Information Center

    Ruder, Robert

    2006-01-01

    To be approachable and visible may be one of the greatest lessons a retired middle level principal ever learned. Being approachable is an expectation of the principalship. Keeping the office door shut or restricting or limiting talk time with students, teachers, or parents sends a strong message to those constituents: "I've got more important…

  18. Quantum approach to Bertrand duopoly

    NASA Astrophysics Data System (ADS)

    Fra¸ckiewicz, Piotr; Sładkowski, Jan

    2016-06-01

    The aim of the paper is to study the Bertrand duopoly example in the quantum domain. We use two ways to write the game in terms of quantum theory. The first one adapts the Li-Du-Massar scheme for the Cournot duopoly. The second one is a simplified model that exploits a two qubit entangled state. In both cases, we focus on finding Nash equilibria in the resulting games. Our analysis allows us to take another look at the classic model of Bertrand.

  19. Forecasting approaches to the Mekong River

    NASA Astrophysics Data System (ADS)

    Plate, E. J.

    2009-04-01

    Hydrologists distinguish between flood forecasts, which are concerned with events of the immediate future, and flood predictions, which are concerned with events that are possible, but whose date of occurrence is not determined. Although in principle both involve the determination of runoff from rainfall, the analytical approaches differ because of different objectives. The differences between the two approaches will be discussed, starting with an analysis of the forecasting process. The Mekong River in south-east Asia is used as an example. Prediction is defined as forecast for a hypothetical event, such as the 100-year flood, which is usually sufficiently specified by its magnitude and its probability of occurrence. It forms the basis for designing flood protection structures and risk management activities. The method for determining these quantities is hydrological modeling combined with extreme value statistics, today usually applied both to rainfall events and to observed river discharges. A rainfall-runoff model converts extreme rainfall events into extreme discharges, which at certain gage points along a river are calibrated against observed discharges. The quality of the model output is assessed against the mean value by means of the Nash-Sutcliffe quality criterion. The result of this procedure is a design hydrograph (or a family of design hydrographs) which are used as inputs into a hydraulic model, which converts the hydrograph into design water levels according to the hydraulic situation of the location. The accuracy of making a prediction in this sense is not particularly high: hydrologists know that the 100-year flood is a statistical quantity which can be estimated only within comparatively wide error bounds, and the hydraulics of a river site, in particular under conditions of heavy sediment loads has many uncertainties. Safety margins, such as additional freeboards are arranged to compensate for the uncertainty of the prediction. Forecasts, on the

  20. A Fast Approach to Bimatrix Games with Intuitionistic Fuzzy Payoffs

    PubMed Central

    Fan, Min; Zou, Ping; Li, Shao-Rong

    2014-01-01

    The aim of this paper is to develop an effective method for solving bimatrix games with payoffs of intuitionistic fuzzy value. Firstly, bimatrix game model with intuitionistic fuzzy payoffs (IFPBiG) was put forward. Secondly, two kinds of nonlinear programming algorithms were discussed with the Nash equilibrium of IFPBiG. Thirdly, Nash equilibrium of the algorithm was proved by the fixed point theory and the algorithm was simplified by linear programming methods. Finally, an example was solved through Matlab; it showed the validity, applicability, and superiority. PMID:25197688

  1. Nonalcoholic Steatohepatitis

    MedlinePlus

    ... approaches under evaluation in patients with NASH include antioxidants, such as vitamin E, selenium, and betaine. These ... for NASH exist. Experimental therapies being studied include antioxidants and antidiabetes medications. [ Top ] Clinical Trials The National ...

  2. On approaches to analyze the sensitivity of simulated hydrologic fluxes to model parameters in the community land model

    SciTech Connect

    Bao, Jie; Hou, Zhangshuan; Huang, Maoyi; Liu, Ying

    2015-12-04

    Here, effective sensitivity analysis approaches are needed to identify important parameters or factors and their uncertainties in complex Earth system models composed of multi-phase multi-component phenomena and multiple biogeophysical-biogeochemical processes. In this study, the impacts of 10 hydrologic parameters in the Community Land Model on simulations of runoff and latent heat flux are evaluated using data from a watershed. Different metrics, including residual statistics, the Nash-Sutcliffe coefficient, and log mean square error, are used as alternative measures of the deviations between the simulated and field observed values. Four sensitivity analysis (SA) approaches, including analysis of variance based on the generalized linear model, generalized cross validation based on the multivariate adaptive regression splines model, standardized regression coefficients based on a linear regression model, and analysis of variance based on support vector machine, are investigated. Results suggest that these approaches show consistent measurement of the impacts of major hydrologic parameters on response variables, but with differences in the relative contributions, particularly for the secondary parameters. The convergence behaviors of the SA with respect to the number of sampling points are also examined with different combinations of input parameter sets and output response variables and their alternative metrics. This study helps identify the optimal SA approach, provides guidance for the calibration of the Community Land Model parameters to improve the model simulations of land surface fluxes, and approximates the magnitudes to be adjusted in the parameter values during parametric model optimization.

  3. On approaches to analyze the sensitivity of simulated hydrologic fluxes to model parameters in the community land model

    DOE PAGESBeta

    Bao, Jie; Hou, Zhangshuan; Huang, Maoyi; Liu, Ying

    2015-12-04

    Here, effective sensitivity analysis approaches are needed to identify important parameters or factors and their uncertainties in complex Earth system models composed of multi-phase multi-component phenomena and multiple biogeophysical-biogeochemical processes. In this study, the impacts of 10 hydrologic parameters in the Community Land Model on simulations of runoff and latent heat flux are evaluated using data from a watershed. Different metrics, including residual statistics, the Nash-Sutcliffe coefficient, and log mean square error, are used as alternative measures of the deviations between the simulated and field observed values. Four sensitivity analysis (SA) approaches, including analysis of variance based on the generalizedmore » linear model, generalized cross validation based on the multivariate adaptive regression splines model, standardized regression coefficients based on a linear regression model, and analysis of variance based on support vector machine, are investigated. Results suggest that these approaches show consistent measurement of the impacts of major hydrologic parameters on response variables, but with differences in the relative contributions, particularly for the secondary parameters. The convergence behaviors of the SA with respect to the number of sampling points are also examined with different combinations of input parameter sets and output response variables and their alternative metrics. This study helps identify the optimal SA approach, provides guidance for the calibration of the Community Land Model parameters to improve the model simulations of land surface fluxes, and approximates the magnitudes to be adjusted in the parameter values during parametric model optimization.« less

  4. Hydrologic calibration of paired watersheds using a MOSUM approach

    NASA Astrophysics Data System (ADS)

    Ssegane, H.; Amatya, D. M.; Muwamba, A.; Chescheir, G. M.; Appelboom, T.; Tollner, E. W.; Nettles, J. E.; Youssef, M. A.; Birgand, F.; Skaggs, R. W.

    2015-01-01

    Paired watershed studies have historically been used to quantify hydrologic effects of land use and management practices by concurrently monitoring two neighboring watersheds (a control and a treatment) during the calibration (pre-treatment) and post-treatment periods. This study characterizes seasonal water table and flow response to rainfall during the calibration period and tests a change detection technique of moving sums of recursive residuals (MOSUM) to select calibration periods for each control-treatment watershed pair when the regression coefficients for daily water table elevation (WTE) were most stable to reduce regression model uncertainty. The control and treatment watersheds included 1-3 year intensively managed loblolly pine (Pinus taeda L.) with natural understory, same age loblolly pine intercropped with switchgrass (Panicum virgatum), 14-15 year thinned loblolly pine with natural understory (control), and switchgrass only. Although monitoring during the calibration period spanned 2009 to 2012, silvicultural operational practices that occurred during this period such as harvesting of existing stand and site preparation for pine and switchgrass establishment may have acted as external factors, potentially shifting hydrologic calibration relationships between control and treatment watersheds. Results indicated that MOSUM was able to detect significant changes in regression parameters for WTE due to silvicultural operations. This approach also minimized uncertainty of calibration relationships which could otherwise mask marginal treatment effects. All calibration relationships developed using this MOSUM method were quantifiable, strong, and consistent with Nash-Sutcliffe Efficiency (NSE) greater than 0.97 for WTE and NSE greater than 0.92 for daily flow, indicating its applicability for choosing calibration periods of paired watershed studies.

  5. NARSTO SOS99NASH WP3D CHEMISTRY DATA

    Atmospheric Science Data Center

    2014-04-25

    ... Level:  L2 Platform:  Ground Station Instrument:  Chemiluminescence UV Ozone Detector ... Oxide Nitrogen Dioxide Nitrogen Oxides Ozone Total 'Reactive' Nitrogen Order Data:  ASDC Order Tool:   ...

  6. Exhaustible resources and cartels: an intertemporal Nash-Cournot model

    SciTech Connect

    Ulph, A.M.; Folie, G.M.

    1980-11-01

    This paper presents an analysis of the effects of the formation of a cartel in an industry extracting an exhaustible resource, where the cartel and competitive fringe have different costs of production. The important result of this paper is that cartelization can cause the rents on the fringe resources to fall, which is contrary to the results obtained if the usual cost assumption is invoked that all firms have identical cost functions. This result is proved for the special case of constant marginal costs, with the cartel enjoying a significant cost advantage. However, the result is more general and can occur even if the cartel enjoys only a slight cost advantage, and may also occur if there are convex rather than linear cost functions. The analysis also reveals that the patterns of production by both the fringe firms and the cartel will be altered by cartelization. 4 figures, 9 references.

  7. Tricyclic sesquiterpenes from Vetiveria zizanoides (L.) Nash as antimycobacterial agents.

    PubMed

    Dwivedi, Gaurav R; Gupta, Shikha; Roy, Sudeep; Kalani, Komal; Pal, Anirban; Thakur, Jay P; Saikia, Dharmendra; Sharma, Ashok; Darmwal, Nandan S; Darokar, Mahendra P; Srivastava, Santosh K

    2013-11-01

    Two bioactive constituents, khusenic acid (1) and khusimol (2), were isolated and characterized from hexane fraction of Vetiveria zizanoides roots. Compounds, 1 and 2, were tested against the various drug-resistant mutants of Mycobacterium smegmatis. The results showed that compound 1 was 4 times more active than the standard drugs ciprofloxacin (CF) and nalidixic acid (NA) against the ciprofloxacin (CSC 101) and lomefloxacin(LOMR5)-resistant mutants, whereas the compound 2 was 2 times more active against the CSC 101 than the NA and CF. Further, these compounds were tested against the virulent strain H37Rv of Mycobacterium tuberculosis, which showed that 1 was two times more active than NA, while 2 was equally active to NA. In in silico docking study, 1 showed better binding affinity than 2 with both subunits of the bacterial DNA gyrase, which was further confirmed from the in vitro bacterial DNA gyrase inhibition study. The in silico ADME analysis of 1 and 2 showed better intestinal absorption, aqueous solubility and ability to penetrate blood-brain barrier. Finally, compound 2 was found safe at the highest dose of 2000 mg/kg body weight. Being edible, fragrant natural products, 1 and 2 will have advantage over the existing synthetic drugs. PMID:23841574

  8. Saddle-Point Properties and Nash Equilibria for Channel Games

    NASA Astrophysics Data System (ADS)

    Mathar, Rudolf; Schmeink, Anke

    2009-12-01

    In this paper, transmission over a wireless channel is interpreted as a two-person zero-sum game, where the transmitter gambles against an unpredictable channel, controlled by nature. Mutual information is used as payoff function. Both discrete and continuous output channels are investigated. We use the fact that mutual information is a convex function of the channel matrix or noise distribution densities, respectively, and a concave function of the input distribution to deduce the existence of equilibrium points for certain channel strategies. The case that nature makes the channel useless with zero capacity is discussed in detail. For each, the discrete, continuous, and mixed discrete-continuous output channel, the capacity-achieving distribution is characterized by help of the Karush-Kuhn-Tucker conditions. The results cover a number of interesting examples like the binary asymmetric channel, the Z-channel, the binary asymmetric erasure channel, and the [InlineEquation not available: see fulltext.]-ary symmetric channel. In each case, explicit forms of the optimum input distribution and the worst channel behavior are achieved. In the mixed discrete-continuous case, all convex combinations of some noise-free and maximum-noise distributions are considered as channel strategies. Equilibrium strategies are determined by extending the concept of entropy and mutual information to general absolutely continuous measures.

  9. Limitations of the Nash Logoscope or diagnostic slide rule.

    PubMed

    Pain, R W

    1975-11-01

    The diagnostic efficacy of a commercially available diagnostic slide-rule (the Logoscope) was evaluated on 50 cases detailed in the leterature. In only 13 cases (26%) was the Logoscope of any practical assistance in diagnosis and even then it did not always indicate the entire final clinical diagnosis. Some major deficiencies of the Logoscope system are outlined. PMID:1207559

  10. NARSTO SOS99NASH SURFACE MET CHEM DATA

    Atmospheric Science Data Center

    2014-04-25

    ... Instrument:  Thermistor Anemometer Film Hygrometer Pyranometer UV Ozone Detector NDIR Gas Analyzer ... Monixide Nitrogen Oxides Sulfur Dioxide Ozone Solar Radiation Humidity Surface Winds Air Temperature Order ...

  11. Joint Network Selection and Discrete Power Control in Heterogeneous MIMO Networks: A Game Theoretical Approach

    NASA Astrophysics Data System (ADS)

    Chen, Gang; Tian, Hua; Xie, Wei; Zhong, Wei

    2013-09-01

    Next-generation wireless networks will integrate multiple wireless access technologies and the users will access the network using one of several available radio access technologies. In this paper, we study the spectrum access problem in heterogeneous multipleinput multiple-output (MIMO) networks through a game theoretic approach. The spectrum access problem in the considered system model is defined as joint network selection and discrete power control. We formulate the problem as a noncooperative game where the players are the multi-mode terminals and. The proposed common utility function takes both transmission rate and the power consumption into account. This game is shown to be a potential game which possess at least one pure strategy Nash equilibrium (NE) and the optimal strategy profile which maximizes the total energy efficiency of the heterogeneous MIMO network constitutes a pure strategy NE of our proposed game. Furthermore, we prove that the price of anarchy of the proposed game is equal to 1. In order to achieve the pure strategy NE, we design an iterative spectrum access algorithm. The convergence and the complexity of our designed algorithm is discussed. It is shown that the designed algorithm can achieve optimal performance with low complexity.

  12. Curriculum: Which Approach?

    ERIC Educational Resources Information Center

    Rulloda, Rudolfo Barcena

    2010-01-01

    Curriculum has two major approaches, technical and scientific approach and the nontechnical-nonscientific approach. Both are different and distinct. Schools need to distinguish which approach is suited for their students.

  13. Estimating Model Parameter Uncertainty Using A Distribution Oriented Approach and a Similarity Measure

    NASA Astrophysics Data System (ADS)

    Tcherednichenko, I. A.; Bastidas, L. A.; Lansey, K.

    2004-12-01

    We use two very recently introduced in hydrology measures of performance: the Distributions Oriented (DO) approach and a set theory-based similarity metric - the Hausdorff Norm (HN) to evaluate the performance of two extensively used distributed rainfall-runoff models: Topmodel and PRMS. The distribution oriented approach considers the bivariate distribution of model outputs and observations and the corresponding marginal distributions. The Hausdorff norm allows for the inclusion, within the same framework or measure, both the spatial and temporal scales as a single multi-dimensional array. The performance evaluation is carried out over different time and spatial scales. The models are run over two nested catchments located in different climatic environments - one relatively wet, the Blue River in Oklahoma, and other semi-arid - the Sycamore Creek in Arizona. The levels and quality of input information are very dissimilar. To drive the models radar precipitation is used for the Blue River while the products generated at the University of Washington and gage measurements are used for Sycamore Creek. Both catchments have nested gages and the models are run to simulate 10 years of daily runoff at those points with different levels of discretization/resolution. Both measures: the DO and the HN, are used for parameter estimation using the multiple objective framework developed at the University of Arizona -that allows for the inclusion of trade-off uncertainties of the objective functions, and are compared against each other and against traditional scalar measures of performance as Nash Sutcliffe efficiency, bias, and general duration curves. In the Sycamore Creek a PRMS parameterization of the channel transmission losses is also considered for evaluation because of the important role played by those losses in the shape of the hydrographs.

  14. Statistical downscaling of rainfall: a non-stationary and multi-resolution approach

    NASA Astrophysics Data System (ADS)

    Rashid, Md. Mamunur; Beecham, Simon; Chowdhury, Rezaul Kabir

    2016-05-01

    A novel downscaling technique is proposed in this study whereby the original rainfall and reanalysis variables are first decomposed by wavelet transforms and rainfall is modelled using the semi-parametric additive model formulation of Generalized Additive Model in Location, Scale and Shape (GAMLSS). The flexibility of the GAMLSS model makes it feasible as a framework for non-stationary modelling. Decomposition of a rainfall series into different components is useful to separate the scale-dependent properties of the rainfall as this varies both temporally and spatially. The study was conducted at the Onkaparinga river catchment in South Australia. The model was calibrated over the period 1960 to 1990 and validated over the period 1991 to 2010. The model reproduced the monthly variability and statistics of the observed rainfall well with Nash-Sutcliffe efficiency (NSE) values of 0.66 and 0.65 for the calibration and validation periods, respectively. It also reproduced well the seasonal rainfall over the calibration (NSE = 0.37) and validation (NSE = 0.69) periods for all seasons. The proposed model was better than the tradition modelling approach (application of GAMLSS to the original rainfall series without decomposition) at reproducing the time-frequency properties of the observed rainfall, and yet it still preserved the statistics produced by the traditional modelling approach. When downscaling models were developed with general circulation model (GCM) historical output datasets, the proposed wavelet-based downscaling model outperformed the traditional downscaling model in terms of reproducing monthly rainfall for both the calibration and validation periods.

  15. Hierarchical Mixture of Experts and Diagnostic Modeling Approach to Reduce Hydrologic Model Structural Uncertainty

    NASA Astrophysics Data System (ADS)

    Moges, E. M.; Demissie, Y.; Li, H. Y.

    2014-12-01

    The choice of hydrologic model structures is one of the sources of uncertainty in representing hydrological process. In most applications, a single comprehensive hydrologic model structure might not be able to capture the entire complex and multi-scale interactions among the different components of the hydrologic process adequately. Calibrating such model can result in displacement of errors from structure to parameters, which in turn leads to over-correction and biased parameter values. An alternative to a single model structure is to develop local expert structures that are well suited in representing specific components of the hydrologic system and adaptively integrate them based on an indicator state variable. In this study, the Hierarchical Mixture of Experts (HME) architecture with a modified gating network function is applied to integrate two runoff module structures of the HBV model. The runoff module structures (i.e., buckets number and orientation) are proposed based on their expertise in representing recession flow and flow duration curve. This process based diagnostic framework of local experts provides a skilled platform for HME to effectively capture each distinct characteristic of the hydrograph and stochastically adapt to catchment response through soil moisture as an indicator variable. The approach is tested using two previously studied catchments, the Guadalupe River (Texas) and the French Broad River (North Carolina) from the Model Parameter Estimation Experiment (MOPEX). The results show that the HME approach has a better performance over a single model for both catchments in terms of the Nash Sutcliffe and correlation coefficient. Furthermore, we have developed and applied a comprehensive performance assessment matrix based on information theory to evaluate the differences between model and observation in terms of different characteristics of the hydrograph.

  16. Using game theory approach to interpret stable policies for Iran's oil and gas common resources conflicts with Iraq and Qatar

    NASA Astrophysics Data System (ADS)

    Esmaeili, Maryam; Bahrini, Aram; Shayanrad, Sepideh

    2015-08-01

    Oil and gas as the non-renewable resources are considered very valuable for the countries with petroleum economics. These resources are not only diffused equally around the world, but also they are common in some places which their neighbors often come into conflicts. Consequently, it is vital for those countries to manage their resource utilization. Lately, game theory was applied in conflict resolution of common resources, such as water, which is a proof of its efficacy and capability. This paper models the conflicts between Iran and its neighbors namely Qatar and Iraq between their oil and gas common resources using game theory approach. In other words, the future of these countries will be introduced and analyzed by some well-known 2 × 2 games to achieve a better perspective of their conflicts. Because of information inadequacy of the players, in addition to Nash Stability, various solution concepts are used based on the foresight, disimprovements, and knowledge of preferences. The results of mathematical models show how the countries could take a reasonable strategy to exploit their common resources.

  17. Clinical approaches to non-alcoholic fatty liver disease

    PubMed Central

    Schwenger, Katherine JP; Allard, Johane P

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), leading to fibrosis and potentially cirrhosis, and it is one of the most common causes of liver disease worldwide. NAFLD is associated with other medical conditions such as metabolic syndrome, obesity, cardiovascular disease and diabetes. NASH can only be diagnosed through liver biopsy, but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis, reducing the need for liver biopsy and risk to patients. Disease progression varies between individuals and is linked to a number of risk factors. Mechanisms involved in the pathogenesis are associated with diet and lifestyle, influx of free fatty acids to the liver from adipose tissue due to insulin resistance, hepatic oxidative stress, cytokines production, reduced very low-density lipoprotein secretion and intestinal microbiome. Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD. Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial. Omega 3 polyunsaturated fatty acids and statins may offer additional benefits. Bariatric surgery should be considered in morbidly obese patients. More research is needed to assess the impact of these treatments on a long-term basis. The objective of this article is to briefly review the diagnosis, management and treatment of this disease in order to aid clinicians in managing these patients. PMID:24587650

  18. Morpheus Surface Approach

    NASA Video Gallery

    This animation shows the Project Morpheus lander flying a kilometer-long simulated surface approach while avoiding hazards in a landing field. The approach takes place at the Shuttle Landing Facili...

  19. Holistic Approaches to Health.

    ERIC Educational Resources Information Center

    Dinkmeyer, Don; Dinkmeyer, Don, Jr.

    1979-01-01

    The holistic approach to health includes a spectrum of concepts that have an important influence on our health. Elementary school counselors must recognize this previously neglected need for a holistic approach. Stress, relaxation response, biofeedback, and the orthomolecular approach are discussed. (Author/BEF)

  20. Endoscopic thyroidectomy: retroauricular approach.

    PubMed

    Lee, Doh Young; Baek, Seung-Kuk; Jung, Kwang-Yoong

    2016-06-01

    The incidence of thyroid cancer has abruptly increased recently, with a female predominance. Conventional thyroidectomy using transcervical incision inevitably leaves an unfavorable neck scar; therefore, various extracervical approaches have been introduced to improve cosmetic satisfaction after thyroidectomy. Several reports demonstrated that these extracervical approaches have advantages not only in terms of cosmesis but also in terms of surgical outcomes and postoperative functional preservation. The retroauricular approach has advantages as the dissection area is smaller than that in the transaxillary approach (TA) and surgical anatomy is familiar to the head and neck surgeons. In addition, there is no concern about paresthesia around the nipple or anterior chest, and surgical direction makes central neck dissection easier than with the other extracervical approaches. Herein, we aim to introduce the surgical procedure of retroauricular approach thyroidectomy and present our experiences of postoperative outcomes. PMID:27294041

  1. Endoscopic thyroidectomy: retroauricular approach

    PubMed Central

    Lee, Doh Young; Baek, Seung-Kuk

    2016-01-01

    The incidence of thyroid cancer has abruptly increased recently, with a female predominance. Conventional thyroidectomy using transcervical incision inevitably leaves an unfavorable neck scar; therefore, various extracervical approaches have been introduced to improve cosmetic satisfaction after thyroidectomy. Several reports demonstrated that these extracervical approaches have advantages not only in terms of cosmesis but also in terms of surgical outcomes and postoperative functional preservation. The retroauricular approach has advantages as the dissection area is smaller than that in the transaxillary approach (TA) and surgical anatomy is familiar to the head and neck surgeons. In addition, there is no concern about paresthesia around the nipple or anterior chest, and surgical direction makes central neck dissection easier than with the other extracervical approaches. Herein, we aim to introduce the surgical procedure of retroauricular approach thyroidectomy and present our experiences of postoperative outcomes. PMID:27294041

  2. Nonlinear dynamics and global analysis of a heterogeneous Cournot duopoly with a local monopolistic approach versus a gradient rule with endogenous reactivity

    NASA Astrophysics Data System (ADS)

    Cavalli, Fausto; Naimzada, Ahmad; Tramontana, Fabio

    2015-06-01

    We study a heterogeneous duopolistic Cournotian game, in which the firms, producing a homogeneous good, have reduced rationality and respectively adopt a "Local Monopolistic Approximation" (LMA) and a gradient-based approach with endogenous reactivity, in an economy characterized by isoelastic demand function and linear total costs. We give conditions on reactivity and marginal costs under which the solution converges to the Cournot-Nash equilibrium. Moreover, we compare the stability regions of the proposed oligopoly to a similar one, in which the LMA firm is replaced by a best response firm, which is more rational than the LMA firm. We show that, depending on costs ratio, the equilibrium can lose its stability in two different ways, through both a flip and a Neimark-Sacker bifurcation. We show that the nonlinear, noninvertible map describing the model can give rise to several coexisting stable attractors (multistability). We analytically investigate the shape of the basins of attractions, in particular proving the existence of regions known in the literature as lobes.

  3. Treatment of patients with type 2 diabetes and non-alcoholic fatty liver disease: current approaches and future directions.

    PubMed

    Cusi, Kenneth

    2016-06-01

    Non-alcoholic fatty liver disease (NAFLD) is reaching epidemic proportions in patients with type 2 diabetes. Patients with NAFLD are at increased risk of more aggressive liver disease (non-alcoholic steatohepatitis [NASH]) and at a higher risk of death from cirrhosis, hepatocellular carcinoma and cardiovascular disease. Dysfunctional adipose tissue and insulin resistance play an important role in the pathogenesis of NASH, creating the conditions for hepatocyte lipotoxicity. Mitochondrial defects are at the core of the paradigm linking chronic excess substrate supply, insulin resistance and NASH. Recent work indicates that patients with NASH have more severe insulin resistance and lipotoxicity compared with matched obese controls with only isolated steatosis. This review focuses on available agents and future drugs under development for the treatment of NAFLD/NASH in type 2 diabetes. Reversal of lipotoxicity with pioglitazone is associated with significant histological improvement, which occurs within 6 months and persists with continued treatment (or for at least 3 years) in patients with prediabetes or type 2 diabetes, holding potential to modify the natural history of the disease. These results also suggest that pioglitazone may become the standard of care for this population. Benefit has also been reported in non-diabetic patients. Recent promising results with glucagon-like peptide 1 receptor agonists have opened another new treatment avenue for NASH. Many agents in Phase 2-3 of development are being tested, aiming to restore glucose/lipid metabolism, ameliorate adipose tissue and liver inflammation, or to inhibit liver fibrosis. By targeting a diversity of relevant pathways, combination therapy in NASH will likely provide greater success in the future. In summary, increased clinical awareness and improved screening strategies (as currently done for diabetic retinopathy and nephropathy) are needed, to translate recent treatment progress into early treatment

  4. Critical Approaches to Film.

    ERIC Educational Resources Information Center

    Bywater, Timothy Robert

    This study deals primarily with recent academically oriented critical material, but it also embraces the range of film criticism that has been written for the mass audience in newspapers and periodicals. The study considers eight types of critical approaches to analyzing film: the journalistic approach, which contains both a reportorial-review and…

  5. Approaches to Truancy Prevention.

    ERIC Educational Resources Information Center

    Mogulescu, Sara; Segal, Heidi J.

    This report examines how New York counties can systematically and programmatically improve approaches to managing persons in need of supervision (PINS), describing approaches to truancy prevention and diversion that have been instituted nationwide and may be applicable to the PINS operating system. Researchers surveyed truancy-specific programs…

  6. Stuttering-Psycholinguistic Approach

    ERIC Educational Resources Information Center

    Hategan, Carolina Bodea; Anca, Maria; Prihoi, Lacramioara

    2012-01-01

    This research promotes psycholinguistic paradigm, it focusing in delimitating several specific particularities in stuttering pathology. Structural approach, on language sides proves both the recurrent aspects found within specialized national and international literature and the psycholinguistic approaches dependence on the features of the…

  7. The NLERAP Approach

    ERIC Educational Resources Information Center

    Nieto, Sonia; Rivera, Melissa; Irizarry, Jason

    2012-01-01

    From the start, NLERAP has been based on two major premises: one is that a sociocultural and sociopolitical approach to learning is more effective than a traditional approach, particularly in the case of populations that have historically been marginalized through their education; and the second is that research is more meaningful and inclusive…

  8. The Strategies Instructional Approach.

    ERIC Educational Resources Information Center

    Deshler, Donald D.; Lenz, B. Keith

    1989-01-01

    The strategies instructional approach developed at the University of Kansas Institute for Research in Learning Disabilities is described. The approach teaches students strategies in the academic, social, motivational, and executive functioning areas that will enable students to meet content learning demands and modifies instructional environments…

  9. Modular Approach for Ethics

    ERIC Educational Resources Information Center

    Wyne, Mudasser F.

    2010-01-01

    It is hard to define a single set of ethics that will cover an entire computer users community. In this paper, the issue is addressed in reference to code of ethics implemented by various professionals, institutes and organizations. The paper presents a higher level model using hierarchical approach. The code developed using this approach could be…

  10. The case study approach

    PubMed Central

    2011-01-01

    The case study approach allows in-depth, multi-faceted explorations of complex issues in their real-life settings. The value of the case study approach is well recognised in the fields of business, law and policy, but somewhat less so in health services research. Based on our experiences of conducting several health-related case studies, we reflect on the different types of case study design, the specific research questions this approach can help answer, the data sources that tend to be used, and the particular advantages and disadvantages of employing this methodological approach. The paper concludes with key pointers to aid those designing and appraising proposals for conducting case study research, and a checklist to help readers assess the quality of case study reports. PMID:21707982

  11. Approaches to Human Communication.

    ERIC Educational Resources Information Center

    Budd, Richard W., Ed.; Ruben, Brent D., Ed.

    This anthology of essays approaches human communication from the points of view of: anthropology, art biology, economics, encounter groups, semantics, general system theory, history, information theory, international behavior, journalism, linguistics, mass media, neurophysiology, nonverbal behavior, organizational behavior, philosophy, political…

  12. Tiny Asteroid Approaches Earth

    NASA Video Gallery

    On Oct. 15, 2010, NASA astronomer Rob Suggs captured this view of the tiny asteroid 2010 TG19 as it made its way among the stars of the constellation Pegasus. It will continue to approach during th...

  13. SOHO Sees Venus' Approach

    NASA Video Gallery

    This video taken by the Solar and Heliospheric Observatory (SOHO) shows the Sun's corona and Venus' approach for the transit. This was taken with the Extreme ultraviolet Imaging Telescope (EIT) in ...

  14. Interdisciplinary Approaches to Astronomy.

    ERIC Educational Resources Information Center

    Fraknoi, Andrew

    1986-01-01

    Provides a bibliography of materials which deal with astronomy and: (1) science fiction; (2) poetry; (3) general fiction; (4) music; (5) psychology; and (6) the law. Also cites two general references on interdisciplinary approaches with astronomy topics. (JN)

  15. Use of slope and feature cues in pigeon (Columba livia) goal-searching behavior.

    PubMed

    Nardi, Daniele; Mauch, Roseanne J; Klimas, Diana B; Bingman, Verner P

    2012-08-01

    Terrain slope provides a directional frame of reference for reorientation and navigation, similar to cardinal directions. Previous studies have shown that, in a goal location task, slope is a very salient cue and that pigeons tend to rely on it even if it is not the most informative cue. Such a strong dependence on one type of information, when there are more effective predictors of reward, is a key premise for a modular view of information processing. Here we tested the provocative hypothesis of a "slope module" for reorientation in slanted environments. Pigeons had to solve a goal location task using slope or another, theoretically salient cue: a beacon feature. Overall, searching behavior was controlled almost equally by the two cues. The fact that, for the first time, slope failed to capture most of the associative strength allows us to reject a strong modularity view and suggests instead that there is competition between cues based on salience. As an interesting additional finding, the reliance on slope and the feature was affected by training location (uphill vs. downhill), suggesting the possibility of a modulatory role of effort on the cue-weighting mechanism of reorientation. PMID:22390622

  16. Group decisions and individual differences: route fidelity predicts flight leadership in homing pigeons (Columba livia)

    PubMed Central

    Freeman, Robin; Mann, Richard; Guilford, Tim; Biro, Dora

    2011-01-01

    How social-living animals make collective decisions is currently the subject of intense scientific interest, with increasing focus on the role of individual variation within the group. Previously, we demonstrated that during paired flight in homing pigeons, a fully transitive leadership hierarchy emerges as birds are forced to choose between their own and their partner's habitual routes. This stable hierarchy suggests a role for individual differences mediating leadership decisions within homing pigeon pairs. What these differences are, however, has remained elusive. Using novel quantitative techniques to analyse habitual route structure, we show here that leadership can be predicted from prior route-following fidelity. Birds that are more faithful to their own route when homing alone are more likely to emerge as leaders when homing socially. We discuss how this fidelity may relate to the leadership phenomenon, and propose that leadership may emerge from the interplay between individual route confidence and the dynamics of paired flight. PMID:20810431

  17. Connectivity and neurochemistry of the commissura anterior of the pigeon (Columba livia).

    PubMed

    Letzner, Sara; Simon, Annika; Güntürkün, Onur

    2016-02-01

    The anterior commissure (AC) and the much smaller hippocampal commissure constitute the only interhemispheric pathways at the telencephalic level in birds. Since the degeneration study from Zeier and Karten (), no detailed description of the topographic organization of the AC has been performed. This information is not only necessary for a better understanding of interhemispheric transfer in birds, but also for a comparative analysis of the evolution of commissural systems in the vertebrate classes. We therefore examined the fiber connections of the AC by using choleratoxin subunit B (CTB) and biotinylated dextran amine (BDA). Injections into subareas of the arcopallium and posterior amygdala (PoA) demonstrated contralateral projection fields within the anterior arcopallium (AA), intermediate arcopallium (AI), PoA, lateral, caudolateral and central nidopallium, dorsal and ventral mesopallium, and medial striatum (MSt). Interestingly, only arcopallial and amygdaloid projections were reciprocally organized, and all AC projections originated within a rather small area of the arcopallium and the PoA. The commissural neurons were not GABA-positive, and thus possibly not of an inhibitory nature. In sum, our neuroanatomical study demonstrates that a small group of arcopallial and amygdaloid neurons constitute a wide range of contralateral projections to sensorimotor and limbic structures. Different from mammals, in birds the neurons that project via the AC constitute mostly heterotopically organized and unidirectional connections. In addition, the great majority of pallial areas do not participate by themselves in interhemispheric exchange in birds. Instead, commissural exchange rests on a rather small arcopallial and amygdaloid cluster of neurons. PMID:26179777

  18. Molecular characterization of Cryptosporidium spp. in domestic pigeons (Columba livia domestica) in Guangdong Province, Southern China.

    PubMed

    Li, Juan; Lin, Xuhui; Zhang, Longxian; Qi, Nanshan; Liao, Shenquan; Lv, Minna; Wu, Caiyan; Sun, Mingfei

    2015-06-01

    To investigate the prevalence and assess the zoonotic transmission burden of Cryptosporidium species in domestic pigeons in Guangdong Province, Southern China, 244 fecal samples were collected from four pigeon breeding farms between June 2012 and March 2013. Cryptosporidium oocysts were purified by Sheather's sugar flotation technique and characterized by DNA sequencing of small subunit ribosomal RNA (SSU rRNA) gene. Cryptosporidium species were determined by comparison of sequences with corresponding Cryptosporidium sequences in GenBank and phylogenetic analysis using neighbor-joining (NJ) in MEGA5.2. The overall prevalence of Cryptosporidium infection in domestic pigeons in Guangdong Province was 0.82% (2/244). Two Cryptosporidium species, namely Cryptosporidium baileyi and Cryptosporidium meleagridis, were identified in Huizhou and Chaozhou farm, respectively. These findings confirmed the existence of C. meleagridis infection in domestic pigeons in China for the first time and provided base-line information for further studies to evaluate the public health risk from pigeon to human. PMID:25773186

  19. An age-related deficit in spatial-feature reference memory in homing pigeons (Columba livia).

    PubMed

    Coppola, Vincent J; Flaim, Mary E; Carney, Samantha N; Bingman, Verner P

    2015-03-01

    Age-related memory decline in mammals has been well documented. By contrast, very little is known about memory decline in birds as they age. In the current study we trained younger and older homing pigeons on a reference memory task in which a goal location could be encoded by spatial and feature cues. Consistent with a previous working memory study, the results revealed impaired acquisition of combined spatial-feature reference memory in older compared to younger pigeons. Following memory acquisition, we used cue-conflict probe trials to provide an initial assessment of possible age-related differences in cue preference. Both younger and older pigeons displayed a similarly modest preference for feature over spatial cues. PMID:25449841

  20. Change blindness in pigeons (Columba livia): the effects of change salience and timing.

    PubMed

    Herbranson, Walter T

    2015-01-01

    Change blindness is a well-established phenomenon in humans, in which plainly visible changes in the environment go unnoticed. Recently a parallel change blindness phenomenon has been demonstrated in pigeons. The reported experiment follows up on this finding by investigating whether change salience affects change blindness in pigeons the same way it affects change blindness in humans. Birds viewed alternating displays of randomly generated lines back-projected onto three response keys, with one or more line features on a single key differing between consecutive displays. Change salience was manipulated by varying the number of line features that changed on the critical response key. Results indicated that change blindness is reduced if a change is made more salient, and this matches previous human results. Furthermore, accuracy patterns indicate that pigeons' effective search area expanded over the course of a trial to encompass a larger portion of the stimulus environment. Thus, the data indicate two important aspects of temporal cognition. First, the timing of a change has a profound influence on whether or not that change will be perceived. Second, pigeons appear to engage in a serial search for changes, in which additional time is required to search additional locations. PMID:26284021

  1. Afferent and efferent projections of the mesopallium in the pigeon (Columba livia).

    PubMed

    Atoji, Yasuro; Wild, J Martin

    2012-03-01

    The mesopallium is a thick cell plate occupying a substantial portion of the avian dorsal pallium, but its hodology is incompletely known. In pigeons we examined fiber connections of the frontodorsal (MFD) and frontoventral mesopallium (MFV), the ventrolateral mesopallium (MVL), the lateral (MIVl) and medial (MIVm) parts of the intermediate ventral mesopallium, and the caudal mesopallium (MC). MFV, MIVl, and MC connect reciprocally with secondary centers of the trigeminal, tectofugal, and auditory systems, respectively. MVL forms reciprocal connections with both the entopallial core and belt. MFV, MIVl, MVL, and MC receive thalamic inputs different from those of primary sensory pallial regions and have reciprocal connections with the caudolateral nidopallium (NCL) or arcopallium. MIVm has a strong reciprocal connection with the intermediate medial nidopallium. It receives afferents from the visual Wulst, rostral MC, posterior dorsointermediate thalamic nucleus, and caudal part of the posterior dorsolateral thalamic nucleus, is connected reciprocally with the arcopallium, and projects to NCL. MFD has reciprocal connections with the medial frontal nidopallium, arcopallium, posterior pallial amygdala, dorsolateral corticoid area, and projects to the medial part of medial striatum and hypothalamus. These results indicate that six subdivisions of the mesopallium have strong connections with corresponding portions of the nidopallium. In particular, the sensory mesopallial components of MFV, MIVl, MVL, and MC form parallel pathways to the one-way sensory streams in the nidopallium and make either feedback or feedforward circuits to the secondary centers of the nidopallium. PMID:21935938

  2. Specialized primary feathers produce tonal sounds during flight in rock pigeons (Columba livia).

    PubMed

    Niese, Robert L; Tobalske, Bret W

    2016-07-15

    For centuries, naturalists have suggested that the tonal elements of pigeon wing sounds may be sonations (non-vocal acoustic signals) of alarm. However, spurious tonal sounds may be produced passively as a result of aeroelastic flutter in the flight feathers of almost all birds. Using mechanistic criteria emerging from recent work on sonations, we sought to: (1) identify characteristics of rock pigeon flight feathers that might be adapted for sound production rather than flight, and (2) provide evidence that this morphology is necessary for in vivo sound production and is sufficient to replicate in vivo sounds. Pigeons produce tonal sounds (700±50 Hz) during the latter two-thirds of each downstroke during take-off. These tones are produced when a small region of long, curved barbs on the inner vane of the outermost primary feather (P10) aeroelastically flutters. Tones were silenced in live birds when we experimentally increased the stiffness of this region to prevent flutter. Isolated P10 feathers were sufficient to reproduce in vivo sounds when spun at the peak angular velocity of downstroke (53.9-60.3 rad s(-1)), but did not produce tones at average downstroke velocity (31.8 rad s(-1)), whereas P9 and P1 feathers never produced tones. P10 feathers had significantly lower coefficients of resultant aerodynamic force (CR) when spun at peak angular velocity than at average angular velocity, revealing that production of tonal sounds incurs an aerodynamic cost. P9 and P1 feathers did not show this difference in CR These mechanistic results suggest that the tonal sounds produced by P10 feathers are not incidental and may function in communication. PMID:27207645

  3. The Differential Outcomes Effect in Pigeons (Columba livia): Is It Truly Anticipatory?

    PubMed

    Kouwenhoven, Marijn; Colombo, Michael

    2016-01-01

    We used delay-interval interference to investigate the nature of the differential outcomes effect (DOE) in pigeons. Birds were trained on a delayed matching-to-sample (DMS) task under either common outcome or differential outcome conditions, and then presented with visual interference during the delay period. Consistent with previous literature, the common outcomes birds were slower to learn the DMS task than the differential outcomes birds. The common outcome birds were also more impaired by the visual interference than the differential outcomes birds. Our findings are consistent with the view that the birds trained with common outcomes were likely remembering the sample stimulus during the delay period, and hence were disrupted by the visual interference, whereas the birds trained with differential outcomes were likely relying on the different emotional reactions elicited by the different outcomes to guide their choice behaviour, and hence were less affected by the visual interference. Our findings suggest that the DOE is not truly evidence of anticipatory mediation of short-term retention in pigeons, but rather emotionally driven decision making, which is not truly anticipatory in nature. PMID:26933892

  4. The effect of display timing on change blindness in pigeons (Columba livia).

    PubMed

    Herbranson, Walter T; Davis, Eva T

    2016-01-01

    Change blindness is a phenomenon in which even obvious changes in a visual scene may go unnoticed. Recent research has indicated that this phenomenon may not be exclusive to humans. Two experiments investigated change blindness in pigeons, using a variant of the widely-used flicker task to investigate the influence of display timing on change blindness. Results indicate that the duration of time during which a stimulus display is visible influences change detection accuracy, with the effect due to additional search time. The results are discussed in relation to the value of comparative cognition and cross-species investigations of behavior. PMID:26609796

  5. Context controls access to working and reference memory in the pigeon (Columba livia).

    PubMed

    Roberts, William A; Macpherson, Krista; Strang, Caroline

    2016-01-01

    The interaction between working and reference memory systems was examined under conditions in which salient contextual cues were presented during memory retrieval. Ambient colored lights (red or green) bathed the operant chamber during the presentation of comparison stimuli in delayed matching-to-sample training (working memory) and during the presentation of the comparison stimuli as S+ and S- cues in discrimination training (reference memory). Strong competition between memory systems appeared when the same contextual cue appeared during working and reference memory training. When different contextual cues were used, however, working memory was completely protected from reference memory interference. PMID:26781056

  6. Pigeons (Columba livia) fail to connect dots in learning biological motion.

    PubMed

    Yamamoto, Eriko; Goto, Kazuhiro; Watanabe, Shigeru

    2015-09-01

    Biological motion point-light displays provide a powerful method for studying motion perception. Nonhuman animals are capable of discriminating point-light displays, but it remains unknown how they perceive biological motion in these displays. We trained two groups of pigeons to discriminate video stimuli using two different classification rules. The motion-congruent group was trained to discriminate full-detail and corresponding point-light displays of pigeons from full-detail and point-light displays of humans. The motion-incongruent group was trained to discriminate full-detail pigeons and point-light humans from the other displays. Both groups acquired the discrimination. When tested with novel displays, pigeons showed good transfer of learning. Transfer was poorest with the point-light displays in the motion-congruent group. The results indicate that the pigeons failed to make the connection between the full-detail displays and their point-light counterparts even when the common motion was available as a cue. PMID:26040957

  7. Genetic characterization of a pigeon paramyxovirus type 1 isolated from Columba livia in Uruguay.

    PubMed

    Castro, E R; Zanetti, F; Arbiza, J

    2012-03-01

    SUMMARY. The isolation and molecular characterization of pigeon paramyxovirus type 1 (PPMV-1) from a sick racing pigeon in Uruguay is reported for the first time. Hemagglutination inhibition (HI) tests were performed to detect antibodies against avian paramyxovirus serotype 1 (APMV-1), and a HI titer of 1/32 was obtained. Tracheal and cloacal swabs were processed by real-time reverse transcription-polymerase chain reaction (rRT-PCR) with the use of the National Veterinary Services Laboratory-U.S. Department of Agriculture validated matrix (M) gene assay and were positive for APMV-1. Viral isolation in embryonated chicken eggs confirmed the molecular detection of the isolate. A fragment corresponding to the 3' region of the fusion (F) protein gene was amplified by RT-PCR, and subsequently sequenced. The deduced amino acid sequence at the F protein cleavage site displayed the motif 112RRQKR/F117. Phylogenetic analysis of this part of the genome allowed the isolated virus to be grouped in the lineage VIb/ 4b, which suggests that it shares the same ecologic niche with other PPMV-1 that were found in the region, and it is not imported as other European or North American viruses. PMID:22545555

  8. An ultrastructural study of the cere of the domestic pigeon (Columba livia).

    PubMed Central

    Purton, M D

    1988-01-01

    The relative scarcity of primary and secondary skin infections in birds depends, at least in part, on the functional morphological barrier presented by the avian integument. Both transmission and scanning electron microscopical techniques were used to study the ultrastructural morphology of the epidermal barrier in the cere of the domestic racing pigeon. The epidermis is composed of sebokeratocytes which are responsible for producing not only the keratin proteins of the keratinized stratum corneum, but also the lipid emulsion forming the surface lipid layer and filling the intercellular spaces. The possible importance and role of these components in the defensive barrier presented by the skin is discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18 Fig. 19 Fig. 20 Fig. 21 Fig. 22 Fig. 23 Fig. 24 Fig. 25 PMID:3198483

  9. Visual discrimination in the pigeon (Columba livia): effects of selective lesions of the nucleus rotundus

    NASA Technical Reports Server (NTRS)

    Laverghetta, A. V.; Shimizu, T.

    1999-01-01

    The nucleus rotundus is a large thalamic nucleus in birds and plays a critical role in many visual discrimination tasks. In order to test the hypothesis that there are functionally distinct subdivisions in the nucleus rotundus, effects of selective lesions of the nucleus were studied in pigeons. The birds were trained to discriminate between different types of stationary objects and between different directions of moving objects. Multiple regression analyses revealed that lesions in the anterior, but not posterior, division caused deficits in discrimination of small stationary stimuli. Lesions in neither the anterior nor posterior divisions predicted effects in discrimination of moving stimuli. These results are consistent with a prediction led from the hypothesis that the nucleus is composed of functional subdivisions.

  10. Cutaneous blood flow in the pigeon Columba livia: its possible relevance to cutaneous water evaporation.

    PubMed

    Ophir, E; Arieli, Y; Marder, J; Horowitz, M

    2002-09-01

    The heat-acclimated rock pigeon is thought to use cutaneous water evaporation (CWE) as the 'preferred' route for heat dissipation, and this mechanism is controlled by adrenergic signaling. In the present study, we tested the hypothesis that adjustments in skin blood flow are a crucial component of this adaptation. Skin blood flow was measured by laser Doppler flowmetry and by ultrasonic flowmetry in heat-acclimated (HAc) and non-acclimated (NAc) pigeons. Skin blood flow, CWE and rectal and skin temperatures were measured under heat exposure (T(a)=50 degrees C) or following propranolol (1.3 mg kg(-1)) or clonidine (80 microg kg(-1)) administration. Using laser Doppler flowmetry, we found a significant increase (1.3-fold) in skin blood flow in the dorsal skin of HAc pigeons following propanolol administration. In contrast, a significant decrease (0.7-fold) was observed in NAc birds. Injection of clonidine resulted in a significant decrease in skin blood flow in both HAc and NAc pigeons (0.4- and 0.5-fold, respectively). Heat exposure increased blood perfusion in both groups (2.5- and 1.8-fold, respectively). Using ultrasonic flowmetry, we showed that both propanolol and clonidine increase the arterial blood flow (Q(a)) in HAc pigeons, while venous blood flow (Q(v)) decreases. In contrast, no significant changes were found in NAc pigeons. As shown by the effect of clonidine, augmentation of skin blood flow is not a prerequisite for CWE, but normally coincides with a greater difference in arterial-venous pressure. Possible regulatory mechanisms are discussed. PMID:12151368

  11. Magnetic field-driven induction of ZENK in the trigeminal system of pigeons (Columba livia)

    PubMed Central

    Lefeldt, Nele; Heyers, Dominik; Schneider, Nils-Lasse; Engels, Svenja; Elbers, Dana; Mouritsen, Henrik

    2014-01-01

    Magnetoreception remains one of the few unsolved mysteries in sensory biology. The upper beak, which is innervated by the ophthalmic branch of the trigeminal nerve (V1), has been suggested to contain magnetic sensors based on ferromagnetic structures. Recently, its existence in pigeons has been seriously challenged by studies suggesting that the previously described iron-accumulations are macrophages, not magnetosensitive nerve endings. This raised the fundamental question of whether V1 is involved in magnetoreception in pigeons at all. We exposed pigeons to either a constantly changing magnetic field (CMF), to a zero magnetic field providing no magnetic information, or to CMF conditions after V1 was cut bilaterally. Using immediate early genes as a marker of neuronal responsiveness, we report that the trigeminal brainstem nuclei of pigeons, which receive V1 input, are activated under CMF conditions and that this neuronal activation disappears if the magnetic stimuli are removed or if V1 is cut. Our data suggest that the trigeminal system in pigeons is involved in processing magnetic field information and that V1 transmits this information from currently unknown, V1-associated magnetosensors to the brain. PMID:25232052

  12. Pigeon's (Columba livia) paradoxical preference for the suboptimal alternative in a complex foraging task.

    PubMed

    Zentall, Thomas R; Case, Jacob P; Luong, Jasmine

    2016-05-01

    Recent research has examined a task in which choice of 1 alternative A provides reinforcement and in addition, allows access to alternative B that also provides reinforcement. However, although initial choice of B also provides reinforcement, it does not also allow access to A. Thus, optimal performance would be to always choose A. Curiously, Salwiczek et al. (2012) reported that adult wrasse (cleaner) fish mastered this task within 50 trials, whereas monkeys and apes had great difficulty with it. The authors attributed the species differences to ecological differences in the species foraging experiences. However, Pepperberg and Hartsfield (2014) found that parrots too learned this task. In Experiment 1, using the manual presentation of stimuli, we found that pigeons actually showed a reliable preference for B, the suboptimal alternative. In Experiment 2, we replicated the suboptimal preference using an automated version of the task. We hypothesized that the pigeons may have been basing their preference on the frequency of reinforcement associated with each alternative (initially, all trials ended with choice of B, whereas only half of the trials involved choice of A). In Experiment 3, we tested the hypothesis that the pigeons' preference was influenced by the frequency of reinforcements associated with A and B. Thus, when the pigeon chose A, we replaced B with C, so reinforcement occurred to B only when they chose it first. With this procedure we found that B was no longer preferred over A. Thus, the data supported our hypothesis. (PsycINFO Database Record PMID:27064201

  13. The complete mitochondrial genome of the Jacobin pigeon (Columba livia breed Jacobin).

    PubMed

    He, Wen-Xiao; Jia, Jin-Feng

    2015-06-01

    The Jacobin is a breed of fancy pigeon developed over many years of selective breeding that originated in Asia. In the present work, we report the complete mitochondrial genome sequence of Jacobin pigeon for the first time. The total length of the mitogenome was 17,245 bp with the base composition of 30.18% for A, 23.98% for T, 31.88% for C, and 13.96% for G and an A-T (54.17 %)-rich feature was detected. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region. The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of Jacobin pigeon would serve as an important data set of the germplasm resources for further study. PMID:25690052

  14. The complete mitochondrial genome of the Feral Rock Pigeon (Columba livia breed feral).

    PubMed

    Li, Chun-Hong; Liu, Fang; Wang, Li

    2014-10-01

    Abstract In the present work, we report the complete mitochondrial genome sequence of feral rock pigeon for the first time. The total length of the mitogenome was 17,239 bp with the base composition of 30.3% for A, 24.0% for T, 31.9% for C, and 13.8% for G and an A-T (54.3 %)-rich feature was detected. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of feral rock pigeon would serve as an important data set of the germplasm resources for further study. PMID:24438239

  15. Characterization of the complete mitochondrial genome of the king pigeon (Columba livia breed king).

    PubMed

    Zhang, Rui-Hua; He, Wen-Xiao; Xu, Tong

    2015-06-01

    The king pigeon is a breed of pigeon developed over many years of selective breeding primarily as a utility breed. In the present work, we report the complete mitochondrial genome sequence of king pigeon for the first time. The total length of the mitogenome was 17,221 bp with the base composition of 30.14% for A, 24.05% for T, 31.82% for C, and 13.99% for G and an A-T (54.22 %)-rich feature was detected. It harbored 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and one non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of king pigeon would serve as an important data set of the germplasm resources for further study. PMID:25648922

  16. The complete mitochondrial genome of the ice pigeon (Columba livia breed ice).

    PubMed

    Zhang, Rui-Hua; He, Wen-Xiao

    2015-02-01

    The ice pigeon is a breed of fancy pigeon developed over many years of selective breeding. In the present work, we report the complete mitochondrial genome sequence of ice pigeon for the first time. The total length of the mitogenome was 17,236 bp with the base composition of 30.2% for A, 24.0% for T, 31.9% for C, and 13.9% for G and an A-T (54.2 %)-rich feature was detected. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of ice pigeon would serve as an important data set of the germplasm resources for further study. PMID:25722036

  17. Mitochondrial genome sequence of Egyptian swift Rock Pigeon (Columba livia breed Egyptian swift).

    PubMed

    Li, Chun-Hong; Shi, Wei; Shi, Wan-Yu

    2015-06-01

    The Egyptian swift Rock Pigeon is a breed of fancy pigeon developed over many years of selective breeding. In this work, we report the complete mitochondrial genome sequence of Egyptian swift Rock Pigeon. The total length of the mitogenome was 17,239 bp and its overall base composition was estimated to be 30.2% for A, 24.0% for T, 31.9% for C and 13.9% for G, indicating an A-T (54.2%)-rich feature in the mitogenome. It contained the typical structure of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a non-coding control region (D-loop region). The complete mitochondrial genome sequence of Egyptian swift Rock Pigeon would serve as an important data set of the germplasm resources for further study. PMID:24438285

  18. The complete mitochondrial genome of the Fancy Pigeon, Columba livia (Columbiformes: Columbidae).

    PubMed

    Zhang, Rui-Hua; Xu, Ming-Ju; Wang, Cun-Lian; Xu, Tong; Wei, Dong; Liu, Bao-Jian; Wang, Guo-Hua

    2015-02-01

    The fancy pigeons are domesticated varieties of the rock pigeon developed over many years of selective breeding. In the present work, we report the complete mitochondrial genome sequence of fancy pigeon for the first time. The total length of the mitogenome was 17,233 bp with the base composition of 30.1% for A, 24.0% for T, 31.9% for C, and 14.0% for G and an A-T (54.2 %)-rich feature was detected. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of fancy pigeon would serve as an important data set of the germplasm resources for further study. PMID:25629469

  19. [Effects of the environment on health of feral pigeons (Columba livia)].

    PubMed

    Schreiber, Tim; Kamphausen, Ludger; Haag-Wackernagel, Daniel

    2015-01-01

    We examined 80 feral pigeons and their fecal samples from two feral pigeon lofts of the "Pigeon Action of Basel" (Switzerland) for different pathogens. The tested material harbored four pathogenic agents transmissible to humans (Chlamydia spp., Salmonella spec., Campylobacter jejuni, Cryptococcus neoformans) In addition several pathogens were found which are no zoonotic agents but potentially pathogenic for the pigeons themselves, such as Trichomonas gallinae, coccidia, helminths, ectoparasites and fungi. The number of pathogens and parasites detected in the fecal samples varied significantly between the two localities. The pigeons of the two investigated breeding flocks differed in nutritional status and the incidence of two species of feather lice, Columbicola columbae and Campanulotes bidentatus compar. The prevalence of Trichomonas gallinae between juveniles and adults was not significantly different but juveniles exhibited significantly heavier infestation if infected. Individuals with a good nutritional status tend to show heavier infestation with Trichomonas gallinae compared to birds with moderate or poor nutritional status. Birds with a poor nutritional status tend to suffer from a heavier infestation with the feather louse C. columbae, and birds with a good nutritional status show significant heavier infestation with C. bidentatus compar. It was remarkable that one of the two investigated breeding populations almost gave up its breeding activity for two years because of the loss of its familiar food source. Nevertheless, this population showed a better nutritional status than the population without restrictions in the acquisition of food. This fact could be interpreted by the existence of a biological control mechanism for suppression of the reproduction in degraded environmental conditions to ensure the survival of the adults. If this assumption is correct, the feeding of feral pigeons by animal lovers possibly causes impairment of pigeon's health in consequence of continuation of the breeding activity in spite of declined living conditions in the city. PMID:25876285

  20. Cue salience influences the use of height cues in reorientation in pigeons (Columba livia).

    PubMed

    Du, Yu; Mahdi, Nuha; Paul, Breanne; Spetch, Marcia L

    2016-07-01

    Although orienting ability has been examined with numerous types of cues, most research has focused only on cues from the horizontal plane. The current study investigated pigeons' use of wall height, a vertical cue, in an open-field task and compared it with their use of horizontal cues. Pigeons were trained to locate food in 2 diagonal corners of a rectangular enclosure with 2 opposite high walls as height cues. Before each trial, pigeons were rotated to disorient them. In training, pigeons could use either the horizontal cues from the rectangular enclosure or the height information from the walls to locate the food. In testing, the apparatus was modified to provide (a) horizontal cues only, (b) height cues only, and (c) both height and horizontal cues in conflict. In Experiment 1 the lower and high walls, respectively, were 40 and 80 cm, whereas in Experiment 2 they were made more perceptually salient by shortening them to 20 and 40 cm. Pigeons accurately located the goal corners with horizontal cues alone in both experiments, but they searched accurately with height cues alone only in Experiment 2. When the height cues conflicted with horizontal cues, pigeons preferred the horizontal cues over the height cues in Experiment 1 but not in Experiment 2, suggesting that perceptual salience influences the relative weighting of cues. (PsycINFO Database Record PMID:27379717

  1. Effect of Hygromycin-B on pigeons (Columba livia) with and without Trichomonas gallinae

    USGS Publications Warehouse

    Kocan, R.M.

    1972-01-01

    Hygromycin-B was administered in varied quantities to pigeons harboring nonvirulent Trichomonas gallinae and to pigeons free of T. gallinae. Both groups responded identically with large yellow caseous lesions in the upper digestive tract which superficially resembled canker (trichomoniasis). No mycotic association with the lesions could be established in either .group from sections stained with periodic acid-Schiff. The lesions observed in Hygromycin-B-treated pigeons were concluded to be the direct result of the drug on the mucosa of the pigeon's upper digestive tract.

  2. Abstract-concept learning carryover effects from the initial training set in pigeons (Columba livia).

    PubMed

    Nakamura, Tamo; Wright, Anthony A; Katz, Jeffrey S; Bodily, Kent D; Sturz, Bradley R

    2009-02-01

    Three groups of pigeons were trained in a same/different task with 32, 64, or 1,024 color-picture stimuli. They were tested with novel transfer pictures. The training-testing cycle was repeated with training-set doublings. The 32-item group learned the same/different task as rapidly as a previous 8-item group and transferred better than the 8-item group at the 32-item training set. The 64- and 1,024-item groups learned the task only somewhat slower than other groups, but their transfer was better and equivalent to baseline performances. These results show that pigeons trained with small sets (e.g., 8 items) have carryover effects that hamper transfer when the training set is expanded. Without carryover effects (i.e., initial transfer from the 32- and 64-item groups), pigeons show the same degree of transfer as rhesus and capuchin monkeys at these same set sizes. This finding has implications for the general ability of abstract-concept learning across species with different neural architectures. PMID:19236147

  3. Feral Pigeons (Columba livia) Prefer Genetically Similar Mates despite Inbreeding Depression.

    PubMed

    Jacob, Gwenaël; Prévot, Anne-Caroline; Baudry, Emmanuelle

    2016-01-01

    Avoidance of mating between related individuals is usually considered adaptive because it decreases the probability of inbreeding depression in offspring. However, mating between related partners can be adaptive if outbreeding depression is stronger than inbreeding depression or if females gain inclusive fitness benefits by mating with close kin. In the present study, we used microsatellite data to infer the parentage of juveniles born in a French colony of feral pigeons, which allowed us to deduce parent pairs. Despite detectable inbreeding depression, we found that pairwise relatedness between mates was significantly higher than between nonmates, with a mean coefficient of relatedness between mates of 0.065, approximately half the theoretical value for first cousins. This higher relatedness between mates cannot be explained by spatial genetic structure in this colonial bird; it therefore probably results from an active choice. As inbreeding but not outbreeding depression is observed in the study population, this finding accords with the idea that mating with genetically similar mates can confer a benefit in terms of inclusive fitness. Our results and published evidence suggest that preference for related individuals as mates might be relatively frequent in birds. PMID:27588754

  4. ECASTAR systems approach

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The methodology of ECASTAR was presented and a discussion of the application of technology to energy conservation was given. This methodology constitutes an overview and blueprint for the analysis of energy conservation actions, and is subdivided into the following sections: the systems approach, constraints and criteria, application of the method (systems approach display, ECASTAR team, study phases and objectives, requirements and impacts, trade-off, integration, and feedback), an example of the method (technology applications).

  5. Cultural Approaches to Parenting

    PubMed Central

    Bornstein, Marc H.

    2012-01-01

    SYNOPSIS This article first introduces some main ideas behind culture and parenting and next addresses philosophical rationales and methodological considerations central to cultural approaches to parenting, including a brief account of a cross-cultural study of parenting. It then focuses on universals, specifics, and distinctions between form (behavior) and function (meaning) in parenting as embedded in culture. The article concludes by pointing to social policy implications as well as future directions prompted by a cultural approach to parenting. PMID:22962544

  6. Ten practice redesign approaches.

    PubMed

    Slayton, Val

    2013-01-01

    As healthcare delivery continues to evolve at a rapid pace, practices need to consider redesign approaches to stay ahead of the pack. From national policy and private payer initiatives to societal macro trends and the growing use of mobile technologies, delivering value, understanding customer needs, and assessing satisfaction are important elements to achieve and maintain success. This article discusses 10 practice redesign approaches. PMID:24228375

  7. Game Theoretic Approach to Post-Docked Satellite Control

    NASA Technical Reports Server (NTRS)

    Hiramatsu, Takashi; Fitz-Coy, Norman G.

    2007-01-01

    This paper studies the interaction between two satellites after docking. In order to maintain the docked state with uncertainty in the motion of the target vehicle, a game theoretic controller with Stackelberg strategy to minimize the interaction between the satellites is considered. The small perturbation approximation leads to LQ differential game scheme, which is validated to address the docking interactions between a service vehicle and a target vehicle. The open-loop solution are compared with Nash strategy, and it is shown that less control efforts are obtained with Stackelberg strategy.

  8. Multi-period natural gas market modeling Applications, stochastic extensions and solution approaches

    NASA Astrophysics Data System (ADS)

    Egging, Rudolf Gerardus

    This dissertation develops deterministic and stochastic multi-period mixed complementarity problems (MCP) for the global natural gas market, as well as solution approaches for large-scale stochastic MCP. The deterministic model is unique in the combination of the level of detail of the actors in the natural gas markets and the transport options, the detailed regional and global coverage, the multi-period approach with endogenous capacity expansions for transportation and storage infrastructure, the seasonal variation in demand and the representation of market power according to Nash-Cournot theory. The model is applied to several scenarios for the natural gas market that cover the formation of a cartel by the members of the Gas Exporting Countries Forum, a low availability of unconventional gas in the United States, and cost reductions in long-distance gas transportation. 1 The results provide insights in how different regions are affected by various developments, in terms of production, consumption, traded volumes, prices and profits of market participants. The stochastic MCP is developed and applied to a global natural gas market problem with four scenarios for a time horizon until 2050 with nineteen regions and containing 78,768 variables. The scenarios vary in the possibility of a gas market cartel formation and varying depletion rates of gas reserves in the major gas importing regions. Outcomes for hedging decisions of market participants show some significant shifts in the timing and location of infrastructure investments, thereby affecting local market situations. A first application of Benders decomposition (BD) is presented to solve a large-scale stochastic MCP for the global gas market with many hundreds of first-stage capacity expansion variables and market players exerting various levels of market power. The largest problem solved successfully using BD contained 47,373 variables of which 763 first-stage variables, however using BD did not result in

  9. Determining satellite close approaches

    NASA Astrophysics Data System (ADS)

    Alfano, Salvatore; Negron, David, Jr.

    1993-06-01

    This paper presents a numerical method to evaluate close approaches of two satellites. The algorithm is based on a space curve modeling technique originally developed by Overhauser, presented here as an independent derivation. The method to determine minimum spacing between two space objects is based on creating a relative distance waveform, delta(t), versus time. The waveform is produced from either uniform or arbitrarily spaced data points, from which intervals of close approach are obtained by extracting the real roots of a localized cubic polynomial. This method is free of both transcendental equations and the computation of acceleration terms of the two objects of interest. For this study, a close approach truth table is constructed using a 0.1 second sequential step along the orbits, then differencing the two position vectors. The close approach entrance and exit times for an ellipsoidal quadric surface are then located using a piecewise linear interpolator, and serve as a benchmark for comparison. The simulation results show this algorithm produces encounter times almost identical to those in the truth table, with a 99.84 percent reduction in computer runtime. The results, created from real orbital data, include solution sets for three operational uses of close-approach logic. For this study, satellite orbital motion is modeled using first-order secular perturbations caused by mass anomalies.

  10. Eponymous hip joint approaches.

    PubMed

    Somford, Matthijs P; Hoornenborg, Daniël; Wiegerinck, Johannes I; Bolder, Stefan B T; Schreurs, Berend W

    2016-07-01

    After the low friction arthroplasty by John Charnley was no longer confined to specialized hospitals but commonplace in the general orthopedic practice, the issue remained how to most optimally reach the hip. The names of the authors of these approaches remain in a lot of cases connected to the approach. By evaluating the original articles in which the approaches are described we ascertain the original description and technique. By various sources we obtained the (short) biography of the people whose name is connected to the approach. Our research covers the biographies of colleagues Smith-Petersen, Watson-Jones, Hardinge, Charnley, Moore and Ludloff. The eponymous approaches are shown and described after the short biography on each individual. This study shows that without the work of our colleagues we cannot proceed in our profession. An understanding and knowledge of the people who dedicated themselves to developing the orthopedic surgery to the high standard it has today is the least honour we should give them. PMID:27139185

  11. Personal Approaches to Career Planning.

    ERIC Educational Resources Information Center

    DeMont, Billie; DeMont, Roger

    1983-01-01

    Identifies four approaches to career planning based on situational leadership theory: the network approach, self-help approach, engineering approach, and mentor approach. Guidelines for the selection of a planning method based on the nature of the work environment and personal preference are discussed. (JAC)

  12. Technical approach document

    SciTech Connect

    Not Available

    1989-12-01

    The Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, Public Law 95-604 (PL95-604), grants the Secretary of Energy the authority and responsibility to perform such actions as are necessary to minimize radiation health hazards and other environmental hazards caused by inactive uranium mill sites. This Technical Approach Document (TAD) describes the general technical approaches and design criteria adopted by the US Department of Energy (DOE) in order to implement remedial action plans (RAPS) and final designs that comply with EPA standards. It does not address the technical approaches necessary for aquifer restoration at processing sites; a guidance document, currently in preparation, will describe aquifer restoration concerns and technical protocols. This document is a second revision to the original document issued in May 1986; the revision has been made in response to changes to the groundwater standards of 40 CFR 192, Subparts A--C, proposed by EPA as draft standards. New sections were added to define the design approaches and designs necessary to comply with the groundwater standards. These new sections are in addition to changes made throughout the document to reflect current procedures, especially in cover design, water resources protection, and alternate site selection; only minor revisions were made to some of the sections. Sections 3.0 is a new section defining the approach taken in the design of disposal cells; Section 4.0 has been revised to include design of vegetated covers; Section 8.0 discusses design approaches necessary for compliance with the groundwater standards; and Section 9.0 is a new section dealing with nonradiological hazardous constituents. 203 refs., 18 figs., 26 tabs.

  13. Structural Margins Assessment Approach

    NASA Technical Reports Server (NTRS)

    Ryan, Robert S.

    1988-01-01

    A general approach to the structural design and verification used to determine the structural margins of the space vehicle elements under Marshall Space Flight Center (MSFC) management is described. The Space Shuttle results and organization will be used as illustrations for techniques discussed. Given also are: (1) the system analyses performed or to be performed by, and (2) element analyses performed by MSFC and its contractors. Analysis approaches and their verification will be addressed. The Shuttle procedures are general in nature and apply to other than Shuttle space vehicles.

  14. Financial Management: An Organic Approach

    ERIC Educational Resources Information Center

    Laux, Judy

    2013-01-01

    Although textbooks present corporate finance using a topical approach, good financial management requires an organic approach that integrates the various assignments financial managers confront every day. Breaking the tasks into meaningful subcategories, the current article offers one approach.

  15. New Ideas and Approaches

    ERIC Educational Resources Information Center

    Lukov, V. A.

    2014-01-01

    The article examines theories of youth that have been proposed in the past few years by Russian scientists, and presents the author's original version of a theory of youth that is based on the thesaurus methodological approach. It addresses the ways in which biosocial characteristics may be reflected in new theories of youth.

  16. Adopting a Pluricentric Approach

    ERIC Educational Resources Information Center

    van Kerckvoorde, Colette

    2012-01-01

    This article argues for a "D-A-CH" approach, which stands for Germany (D), Austria (A), and Switzerland (CH), in language classes from the introductory level on. I begin by tracing the emergence and development of distinct Standard Swiss and Austrian German varieties. I then discuss marketing efforts for Swiss and Austrian German, and…

  17. Nutrition: An Interdisciplinary Approach.

    ERIC Educational Resources Information Center

    Graef, Judy; Pettingell, Margaret S.

    1981-01-01

    Describes a pilot program in which the Dairy, Food and Nutrition Council of East Orange, New Jersey, introduced a new education series entitled "Food in Today's World." This approach outlined the role of the home economist as coordinator of a nutrition program in which educators from various disciplines participate. (CT)

  18. Marxian Approaches to Education.

    ERIC Educational Resources Information Center

    Carnoy, Martin

    Traditional Marxist approaches to the state relegate superstructural institutions like the school to a minor role in the process of social change. More recent theories like those of Gramsci, Althusser, and Poulantzas raise the state and the class struggle in the state apparatuses to a much more prominent position: superstructure, including the…

  19. Systems Approach to Training.

    ERIC Educational Resources Information Center

    British Gas, London (England). Training and Development Dept.

    This pamphlet is intended to assist managers and professional trainers alike in using a systems approach to training. Addressed in the individual sections of the guide are the following topics: identifying the training need (the main job objectives, the conditions under which the job is performed, and the responsibilities it involves); analyzing…

  20. Approaches to acceptable risk

    SciTech Connect

    Whipple, C.

    1997-04-30

    Several alternative approaches to address the question {open_quotes}How safe is safe enough?{close_quotes} are reviewed and an attempt is made to apply the reasoning behind these approaches to the issue of acceptability of radiation exposures received in space. The approaches to the issue of the acceptability of technological risk described here are primarily analytical, and are drawn from examples in the management of environmental health risks. These include risk-based approaches, in which specific quantitative risk targets determine the acceptability of an activity, and cost-benefit and decision analysis, which generally focus on the estimation and evaluation of risks, benefits and costs, in a framework that balances these factors against each other. These analytical methods tend by their quantitative nature to emphasize the magnitude of risks, costs and alternatives, and to downplay other factors, especially those that are not easily expressed in quantitative terms, that affect acceptance or rejection of risk. Such other factors include the issues of risk perceptions and how and by whom risk decisions are made.

  1. Orion Emergency Mask Approach

    NASA Technical Reports Server (NTRS)

    Tuan, George C.; Graf, John C.

    2008-01-01

    Emergency mask approach on Orion poses a challenge to the traditional Shuttle or Station approaches. Currently, in the case of a fire or toxic spill event, the crew utilizes open loop oxygen masks that provide the crew with oxygen to breath, but also dumps the exhaled oxygen into the cabin. For Orion, with a small cabin volume, the extra oxygen will exceed the flammability limit within a short period of time, unless a nitrogen purge is also provided. Another approach to a fire or toxic spill event is the use of a filtering emergency masks. These masks utilize some form of chemical beds to scrub the air clean of toxic providing the crew safe breathing air for a period without elevating the oxygen level in the cabin. Using the masks and a form of smoke-eater filter, it may be possible to clean the cabin completely or to a level for safe transition to a space suit to perform a cabin purge. Issues with filters in the past have been the reaction temperature and high breathing resistance. Development in a new form of chemical filters has shown promise to make the filtering approach feasible.

  2. Orion Emergency Mask Approach

    NASA Technical Reports Server (NTRS)

    Tuan, George C.; Graf, John C.

    2009-01-01

    Emergency mask approach on Orion poses a challenge to the traditional Shuttle or Station approaches. Currently, in the case of a fire or toxic spill event, the crew utilizes open loop oxygen masks that provide the crew with oxygen to breath, but also dumps the exhaled oxygen into the cabin. For Orion, with a small cabin volume, the extra oxygen will exceed the flammability limit within a short period of time, unless a nitrogen purge is also provided. Another approach to a fire or toxic spill event is the use of a filtering emergency masks. These masks utilize some form of chemical beds to scrub the air clean of toxic providing the crew safe breathing air for a period without elevating the oxygen level in the cabin. Using the masks and a form of smoke-eater filter, it may be possible to clean the cabin completely or to a level for safe transition to a space suit to perform a cabin purge. Issues with filters in the past have been the reaction time, breakthroughs, and high breathing resistance. Development in a new form of chemical filters has shown promise to make the filtering approach feasible.

  3. A Fresh Approach

    ERIC Educational Resources Information Center

    Violino, Bob

    2011-01-01

    Facilities and services are a huge drain on community college budgets. They are also vital to the student experience. As funding dries up across the country, many institutions are taking a team approach, working with partner colleges and private service providers to offset costs and generate revenue without sacrificing the services and amenities…

  4. Overview of Curricular Approaches

    ERIC Educational Resources Information Center

    Hartz, Cameo V.; Parker, Jill

    2012-01-01

    Institutions of higher education address the transition from after-college life in a variety of curricular approaches. Articulation agreements provide greater transferability of courses from one college to another, thereby easing the transition for students. Career courses, which are typically taught by career center staff, are a common offering…

  5. Salt repository design approach

    SciTech Connect

    Matthews, S.C.

    1983-01-01

    This paper presents a summary discussion of the approaches that have been and will be taken in design of repository facilities for use with disposal of radioactive wastes in salt formations. Since specific sites have yet to be identified, the discussion is at a general level, supplemented with illustrative examples where appropriate. 5 references, 1 figure.

  6. The Resettlement Approach.

    ERIC Educational Resources Information Center

    McInnis, Kathleen M.

    1983-01-01

    Reports on a follow-up study of secondary migration among Indochinese refugees resettled by Lutheran Social Services of Wisconsin and Upper Michigan. Suggests that cultural misunderstanding, rigid sponsorship approaches, and an insensitivity to the special mental risks of refugee populations have contributed to the incidence of secondary…

  7. Implementation of Communicative Approach

    ERIC Educational Resources Information Center

    Jabeen, Shazi Shah

    2014-01-01

    In the contemporary age of high professional requirements such as excellent communicative skills, the need for successful learning of communicative skills of English language suggests communicative ability to be the goal of language teaching. In other words, to teach English language using communicative approach becomes essential. Studies to…

  8. A New Wavelet Based Approach to Assess Hydrological Models

    NASA Astrophysics Data System (ADS)

    Adamowski, J. F.; Rathinasamy, M.; Khosa, R.; Nalley, D.

    2014-12-01

    In this study, a new wavelet based multi-scale performance measure (Multiscale Nash Sutcliffe Criteria, and Multiscale Normalized Root Mean Square Error) for hydrological model comparison was developed and tested. The new measure provides a quantitative measure of model performance across different timescales. Model and observed time series are decomposed using the a trous wavelet transform, and performance measures of the model are obtained at each time scale. The usefulness of the new measure was tested using real as well as synthetic case studies. The real case studies included simulation results from the Soil Water Assessment Tool (SWAT), as well as statistical models (the Coupled Wavelet-Volterra (WVC), Artificial Neural Network (ANN), and Auto Regressive Moving Average (ARMA) methods). Data from India and Canada were used. The synthetic case studies included different kinds of errors (e.g., timing error, as well as under and over prediction of high and low flows) in outputs from a hydrologic model. It was found that the proposed wavelet based performance measures (i.e., MNSC and MNRMSE) are a more reliable measure than traditional performance measures such as the Nash Sutcliffe Criteria, Root Mean Square Error, and Normalized Root Mean Square Error. It was shown that the new measure can be used to compare different hydrological models, as well as help in model calibration.

  9. Translational approaches: From fatty liver to non-alcoholic steatohepatitis

    PubMed Central

    Rosso, Natalia; Chavez-Tapia, Norberto C; Tiribelli, Claudio; Bellentani, Stefano

    2014-01-01

    Over the past few decades, non-alcoholic fatty liver disease (NAFLD) has become one, if not the most common, cause of chronic liver disease affecting both adults and children. The increasing number of cases at an early age is the most worrying aspect of this pathology, since it provides more time for its evolution. The spectrum of this disease ranges from liver steatosis to steatohepatitis, fibrosis and in some cases, hepatocellular carcinoma. NAFLD may not always be considered a benign disease and hepatologists must be cautious in the presence of fatty liver. This should prompt the use of the available experimental models to understand better the pathogenesis and to develop a rational treatment of a disease that is dangerously increasing. In spite of the growing efforts, the pathogenesis of NAFLD is still poorly understood. In the present article we review the most relevant hypotheses and evidence that account for the progression of NAFLD to non-alcoholic steatohepatitis (NASH) and fibrosis. The available in vitro and in vivo experimental models of NASH are discussed and revised in terms of their validity in translational studies. These studies must be aimed at the discovery of the still unknown triggers or mediators that induce the progression of hepatic inflammation, apoptosis and fibrosis. PMID:25083077

  10. Domain Approach: An Alternative Approach in Moral Education

    ERIC Educational Resources Information Center

    Vengadasalam, Chander; Mamat, Wan Hasmah Wan; Mail, Fauziah; Sudramanian, Munimah

    2014-01-01

    This paper discusses the use of the domain approach in moral education in an upper secondary school in Malaysia. Moral Education needs a creative and an innovative approach. Therefore, a few forms of approaches are used in the teaching-learning of Moral Education. This research describes the use of domain approach which comprises the moral domain…

  11. Republished: Non-alcoholic fatty liver disease: a practical approach to treatment

    PubMed Central

    Dyson, J K; Anstee, Q M; McPherson, S

    2015-01-01

    Non-alcoholic fatty liver disease (NAFLD) affects up to a third of the population in many developed countries. Between 10% and 30% of patients with NAFLD have non-alcoholic steatohepatitis (NASH) that can progress to cirrhosis. There are metabolic risk factors common to both NAFLD and cardiovascular disease, so patients with NASH have an increased risk of liver-related and cardiovascular death. Management of patients with NAFLD depends largely on the stage of disease, emphasising the importance of careful risk stratification. There are four main areas to focus on when thinking about management strategies in NAFLD: lifestyle modification, targeting the components of the metabolic syndrome, liver-directed pharmacotherapy for high risk patients and managing the complications of cirrhosis. PMID:25655252

  12. Non-alcoholic fatty liver disease: a practical approach to treatment

    PubMed Central

    Dyson, J K; Anstee, Q M; McPherson, S

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) affects up to a third of the population in many developed countries. Between 10% and 30% of patients with NAFLD have non-alcoholic steatohepatitis (NASH) that can progress to cirrhosis. There are metabolic risk factors common to both NAFLD and cardiovascular disease, so patients with NASH have an increased risk of liver-related and cardiovascular death. Management of patients with NAFLD depends largely on the stage of disease, emphasising the importance of careful risk stratification. There are four main areas to focus on when thinking about management strategies in NAFLD: lifestyle modification, targeting the components of the metabolic syndrome, liver-directed pharmacotherapy for high risk patients and managing the complications of cirrhosis. PMID:25285192

  13. The imaging spectrometer approach

    NASA Technical Reports Server (NTRS)

    Wellman, J. B.

    1982-01-01

    Two important sensor design drivers are the requirement for spatial registration of the spectral components and the implementation of the advanced multispectral capability, including spectral band width, number of bands and programmability. The dispersive approach, fundamental to the imaging spectrometer concept, achieves these capabilities by utilizing a spectrometer to disperse the spectral content while preserving the spatial identity of the information in the cross-track direction. Area array detectors in the spectrometer focal plane detect and store the spatial and multispectral content for each line of the image. The choice of spectral bands, image IFOV and swath width is implemented by programmed readout of the focal plane. These choices in conjunction with data compression are used to match the output data rate with the telemetry link capability. Progress in the key technologies of optics, focal plane detector arrays, onboard processing, and focal plane cooling supports the viability of the imaging spectrometer approach.

  14. An Approach to Cosmeceuticals.

    PubMed

    Milam, Emily C; Rieder, Evan A

    2016-04-01

    The cosmeceutical industry is a multi-billion dollar, consumer-driven market. Products promise highly desirable anti-aging benefits, but are not subject to regulation. We present an introduction to cosmeceuticals for the general and cosmetic dermatologist, including definitions and explanations of key terms, an approach to the evidence base, a dissection of chamomile and green tea, two paradigmatic cosmeceutical products, and a window into the underlying psychology of this vast marketplace. PMID:27050700

  15. Theoretical Approaches to Nanoparticles

    NASA Astrophysics Data System (ADS)

    Kempa, Krzysztof

    Nanoparticles can be viewed as wave resonators. Involved waves are, for example, carrier waves, plasmon waves, polariton waves, etc. A few examples of successful theoretical treatments that follow this approach are given. In one, an effective medium theory of a nanoparticle composite is presented. In another, plasmon polaritonic solutions allow to extend concepts of radio technology, such as an antenna and a coaxial transmission line, to the visible frequency range.

  16. Disability: a welfarist approach

    PubMed Central

    Savulescu, Julian; Kahane, Guy

    2011-01-01

    In this paper, we offer a new account of disability. According to our account, some state of a person's biology or psychology is a disability if that state makes it more likely that a person's life will get worse, in terms of his or her own wellbeing, in a given set of social and environmental circumstances. Unlike the medical model of disability, our welfarist approach does not tie disability to deviation from normal species’ functioning, nor does it understand disability in essentialist terms. Like the social model of disability, the welfarist approach sees disability as a harmful state that results from the interaction between a person's biology and psychology and his or her surrounding environment. However, unlike the social model, it denies that the harm associated with disability is entirely due to social prejudice or injustice. In this paper, we outline and clarify the welfarist approach, answer common objections and illustrate its usefulness in addressing a range of difficult ethical questions involving disability. PMID:22140353

  17. Computational vaccinology: quantitative approaches.

    PubMed

    Flower, Darren R; McSparron, Helen; Blythe, Martin J; Zygouri, Christianna; Taylor, Debra; Guan, Pingping; Wan, Shouzhan; Coveney, Peter V; Walshe, Valerie; Borrow, Persephone; Doytchinova, Irini A

    2003-01-01

    The immune system is hierarchical and has many levels, exhibiting much emergent behaviour. However, at its heart are molecular recognition events that are indistinguishable from other types of biomacromolecular interaction. These can be addressed well by quantitative experimental and theoretical biophysical techniques, and particularly by methods from drug design. We review here our approach to computational immunovaccinology. In particular, we describe the JenPep database and two new techniques for T cell epitope prediction. One is based on quantitative structure-activity relationships (a 3D-QSAR method based on CoMSIA and another 2D method based on the Free-Wilson approach) and the other on atomistic molecular dynamic simulations using high performance computing. JenPep (http://www.jenner.ar.uk/ JenPep) is a relational database system supporting quantitative data on peptide binding to major histocompatibility complexes, TAP transporters, TCR-pMHC complexes, and an annotated list of B cell and T cell epitopes. Our 2D-QSAR method factors the contribution to peptide binding from individual amino acids as well as 1-2 and 1-3 residue interactions. In the 3D-QSAR approach, the influence of five physicochemical properties (volume, electrostatic potential, hydrophobicity, hydrogen-bond donor and acceptor abilities) on peptide affinity were considered. Both methods are exemplified through their application to the well-studied problem of peptide binding to the human class I MHC molecule HLA-A*0201. PMID:14712934

  18. Enteral approaches in malabsorption.

    PubMed

    Avitzur, Yaron; Courtney-Martin, Glenda

    2016-04-01

    Enteral autonomy and freedom from parenteral nutrition dependency is the ultimate therapeutic goal in children with intestinal failure. This can be achieved following attainment of bowel adaptation in conditions such as short bowel syndrome. Enteral nutrition is a major therapeutic cornerstone in the management of children with intestinal failure. It promotes physiological development, bowel adaptation and enhances weaning from parenteral nutrition. The optimal method of delivery, type of nutrients, timing of initiation, promotion of feeds and transition to solid food in children with short bowel syndrome are debated. Lack of high quality human data hampers evidence based conclusions and impacts daily practices in the field. Clinical approaches and therapeutic decisions are regularly influenced by expert opinion and center practices. This review summarizes the physiological principles, medical evidence and practice recommendations on enteral nutrition approaches in short bowel syndrome and provides a practical framework for daily treatment of this unique group of patients. Oral and tube feeding, bolus and continuous feeding, type of nutrients, formulas, trace elements and solid food options are reviewed. Future collaborative multicenter, high quality clinical trials are needed to support enteral nutrition approaches in intestinal failure. PMID:27086892

  19. Parsec's astrometry direct approaches .

    NASA Astrophysics Data System (ADS)

    Andrei, A. H.

    Parallaxes - and hence the fundamental establishment of stellar distances - rank among the oldest, keyest, and hardest of astronomical determinations. Arguably amongst the most essential too. The direct approach to obtain trigonometric parallaxes, using a constrained set of equations to derive positions, proper motions, and parallaxes, has been labeled as risky. Properly so, because the axis of the parallactic apparent ellipse is smaller than one arcsec even for the nearest stars, and just a fraction of its perimeter can be followed. Thus the classical approach is of linearizing the description by locking the solution to a set of precise positions of the Earth at the instants of observation, rather than to the dynamics of its orbit, and of adopting a close examination of the never many points available. In the PARSEC program the parallaxes of 143 brown dwarfs were aimed at. Five years of observation of the fields were taken with the WIFI camera at the ESO 2.2m telescope, in Chile. The goal is to provide a statistically significant number of trigonometric parallaxes to BD sub-classes from L0 to T7. Taking advantage of the large, regularly spaced, quantity of observations, here we take the risky approach to fit an ellipse in ecliptical observed coordinates and derive the parallaxes. We also combine the solutions from different centroiding methods, widely proven in prior astrometric investigations. As each of those methods assess diverse properties of the PSFs, they are taken as independent measurements, and combined into a weighted least-square general solution.

  20. Integrated Modeling Approach for Verifying Water Storage Services for a Payment for Environmental Service Programs

    NASA Astrophysics Data System (ADS)

    Hendricks, G.; Shukla, S.; Guzha, A. C.

    2013-12-01

    Hydrologic models have been used for improved understanding of how an ecosystem's hydrologic response to human intervention and may provide substantial insight into the viability of payment for environmental services (PES) programs. Little is currently known about how hydrologic models can contribute to the design and evaluation of PES programs. Increased water storage is a desired environmental service (ES) for the Florida Everglades' watershed to reduce nutrient loads and excessive flows to lakes and estuaries in the region. We present monitoring and modeling results to verify the water storage PES for two ranch sites (wetland and watershed scales) located in the Northern Everglades region located north of the Lake Okeechobee (LO). Verification of the water storage PES using at least 3 years of hydrologic data was inconclusive due to variable rainfall during pre- and post-PES periods. An integrated surface and groundwater model, MIKE-SHE/MIKE11, was used to help verify the water storage service as well as predict ecological responses for different water storage scenarios (different levels of storage). The hydrological model was calibrated and validated using field measurements and was able to effectively simulate the surface and groundwater levels for the watershed (Nash Sutcliffe Efficiency, NSE = 0.54 to 0.82) and for surface water levels within wetlands (NSE = 0.54 to 0.84). Scenario analyses for storage levels showed an inverse relationship between board heights for water control structures and flows at the watershed outlet. Changes in flow were marginal when board heights approached a maximum indicating movement of water into subsurface storage. Combining simulation results with field measurements showed reduced flows and increased subsurface storage (2 cm/yr.), a desired outcome for protecting LO and estuarine systems from excessive flows. Simulated wetland water levels were combined with LIDAR-based topography to predict inundation for wetlands at the two

  1. Assessment of hydraulic parameters in the phreatic aquifer of Settolo (Italy): a stochastic approach

    NASA Astrophysics Data System (ADS)

    Salandin, P.; Zovi, F.; Camporese, M.

    2012-12-01

    In this work we present and test against real field data an inversion approach for the identification of hydraulic parameters at the aquifer scale. Our test field is the alluvial phreatic aquifer of Settolo, located along the left bank of the Piave River in a piedmont area in Northeastern Italy, with an extension of approximately 6 km2 and exhibiting heterogeneities of the geological structures both at the local and intermediate scales. The area is characterized by the alluvial sediments (mainly gravel in a sandy matrix) deposited by the Piave River during the Last Glacial Maximum, being the subsurface, with an average aquifer thickness of 50 m, crossed by paleo-riverbeds that probably represent the main hydrogeological unit from which water is withdrawn. The interactions between watercourses and the aquifer, the recharge linked to the precipitation, as well as the dynamics of partially penetrating extraction wells must be properly reproduced for an effective protection and a sustainable exploitation of the water resources. In order to do so, in cooperation with Alto Trevigiano Servizi S.r.l., the local water resources management company, a careful site characterization is in progress since 2009, with a number of different measurements and scales involved. Besides surface ERT, water quality surveys, and a tracer test, we highlight here the role of 18 continuously monitored observation wells, available in the study area for the measurement of the water table dynamics and the calibration/validation of groundwater models. A preliminary comparison with the results of a three-dimensional Richards model demonstrated that the site can be properly described by means of a two-dimensional finite element solver of the nonlinear Dupuit-Boussinesq equation, saving CPU time and computer storage. Starting from an ensemble of randomly generated and spatially correlated hydraulic conductivity (K) fields, the fit between water table observations and model predictions is measured

  2. [Approaches to radial shaft].

    PubMed

    Bartoníček, J; Naňka, O; Tuček, M

    2015-10-01

    In the clinical practice, radial shaft may be exposed via two approaches, namely the posterolateral Thompson and volar (anterior) Henry approaches. A feared complication of both of them is the injury to the deep branch of the radial nerve. No consensus has been reached, yet, as to which of the two approaches is more beneficial for the proximal half of radius. According to our anatomical studies and clinical experience, Thompson approach is safe only in fractures of the middle and distal thirds of the radial shaft, but highly risky in fractures of its proximal third. Henry approach may be used in any fracture of the radial shaft and provides a safe exposure of the entire lateral and anterior surfaces of the radius.The Henry approach has three phases. In the first phase, incision is made along the line connecting the biceps brachii tendon and the styloid process of radius. Care must be taken not to damage the lateral cutaneous nerve of forearm.In the second phase, fascia is incised and the brachioradialis identified by the typical transition from the muscle belly to tendon and the shape of the tendon. On the lateral side, the brachioradialis lines the space with the radial artery and veins and the superficial branch of the radial nerve running at its bottom. On the medial side, the space is defined by the pronator teres in the proximal part and the flexor carpi radialis in the distal part. The superficial branch of the radial nerve is retracted together with the brachioradialis laterally, and the radial artery medially.In the third phase, the attachment of the pronator teres is identified by its typical tendon in the middle of convexity of the lateral surface of the radial shaft. The proximal half of the radius must be exposed very carefully in order not to damage the deep branch of the radial nerve. Dissection starts at the insertion of the pronator teres and proceeds proximally along its lateral border in interval between this muscle and insertion of the supinator

  3. Repository program licensing approach

    SciTech Connect

    Williamson, T.M.; Gil, A.V.

    1994-12-31

    Yucca Mountain, Nevada is currently being studied by the US Department of Energy (DOE) as a potential site for a mined geologic repository for high-level nuclear waste. DOE has the responsibility to determine the suitability of the site and to develop a license application (LA) for authorization to construct the potential repository. If the site is suitable, the license application would be submitted to the US Nuclear Regulatory Commission (NRC). The repository program licensing approach is focused on the timely acquisition of information needed in licensing and the resolution of potential licensing issues with the NRC staff. Licensing involves an iterative process requiring refinements as data are acquired, analyzed, and evaluated. The repository licensing approach presented in this paper ensures that the information is available when needed to facilitate the licensing process. Identifying the information needed to evaluate compliance with the performance objectives in 10 CFR 60, monitoring the acquisition of such information, and developing a successful license application are integral elements of DOE`s repository program licensing approach. Activities to characterize the site are being systematically conducted as planned in the Site Characterization Plan (SCP). In addition, DOE is implementing the issue resolution initiative, the license application annotated outline (LAAO) process, and interim licensability evaluations to update the early planning in the SCP and to focus site characterization, design, and performance assessment activities on the acquisition of information needed for a site suitability determination and licensing. Collectively, the issue resolution initiative, LAAO process, and interim licensability evaluations are key elements of a transition to the iterative process to answer the question: {open_quotes}When do we have enough data to support licensing?{close_quotes}

  4. Approaches to Quantum Gravity

    NASA Astrophysics Data System (ADS)

    Oriti, Daniele

    2009-03-01

    Preface; Part I. Fundamental Ideas and General Formalisms: 1. Unfinished revolution C. Rovelli; 2. The fundamental nature of space and time G. 't Hooft; 3. Does locality fail at intermediate length scales R. Sorkin; 4. Prolegomena to any future quantum gravity J. Stachel; 5. Spacetime symmetries in histories canonical gravity N. Savvidou; 6. Categorical geometry and the mathematical foundations of quantum gravity L. Crane; 7. Emergent relativity O. Dreyer; 8. Asymptotic safety R. Percacci; 9. New directions in background independent quantum gravity F. Markopoulou; Questions and answers; Part II: 10. Gauge/gravity duality G. Horowitz and J. Polchinski; 11. String theory, holography and quantum gravity T. Banks; 12. String field theory W. Taylor; Questions and answers; Part III: 13. Loop Quantum Gravity T. Thiemann; 14. Covariant loop quantum gravity? E. LIvine; 15. The spin foam representation of loop quantum gravity A. Perez; 16. 3-dimensional spin foam quantum gravity L. Freidel; 17. The group field theory approach to quantum gravity D. Oriti; Questions and answers; Part IV. Discrete Quantum Gravity: 18. Quantum gravity: the art of building spacetime J. Ambjørn, J. Jurkiewicz and R. Loll; 19. Quantum Regge calculations R. Williams; 20. Consistent discretizations as a road to quantum gravity R. Gambini and J. Pullin; 21. The causal set approach to quantum gravity J. Henson; Questions and answers; Part V. Effective Models and Quantum Gravity Phenomenology: 22. Quantum gravity phenomenology G. Amelino-Camelia; 23. Quantum gravity and precision tests C. Burgess; 24. Algebraic approach to quantum gravity II: non-commutative spacetime F. Girelli; 25. Doubly special relativity J. Kowalski-Glikman; 26. From quantum reference frames to deformed special relativity F. Girelli; 27. Lorentz invariance violation and its role in quantum gravity phenomenology J. Collins, A. Perez and D. Sudarsky; 28. Generic predictions of quantum theories of gravity L. Smolin; Questions and

  5. The collaboratory approach

    SciTech Connect

    Peskin, A.M.

    1997-04-01

    A {open_quotes}collaboratory{close_quotes} has been defined as a center without walls, in which researchers can perform their work without regard to geographical location. To an increasing degree, engineering design and development is also taking the form of far-flung collaborations among divisions of a plant, subcontractors, university consultants and customers. It has long been recognized that quality engineering education presents the student with an environment that duplicates as much as possible that which the graduate will encounter in industry. To that end, it is important that engineering schools begin to introduce the collaboratory approach in its preparation, and even use it in delivery of subject matter to students.

  6. Combined approach brings success.

    PubMed

    Law, Oliver

    2014-06-01

    Sixteen months ago, according to Trumpf Medical Systems, which managed the project, 'something out of the ordinary' happened at Leighton Hospital in Crewe. When making plans to upgrade ageing operating theatres and critical care units, the estates department took the decision to involve other disciplines from the very start of the process. Clinicians, nursing staff, architects, patient representatives, and suppliers, all played their part, with the estates team always at the hub. As Oliver Law, managing director of the UK medical technology specialist, explains, this multidisciplinary approach had a profound effect on the outcome. PMID:25004555

  7. Approaches to Numerical Relativity

    NASA Astrophysics Data System (ADS)

    d'Inverno, Ray

    2005-07-01

    Introduction Ray d'Inverno; Preface C. J. S. Clarke; Part I. Theoretical Approaches: 1. Numerical relativity on a transputer array Ray d'Inverno; 2. Some aspects of the characteristic initial value problem in numerical relativity Nigel Bishop; 3. The characteristic initial value problem in general relativity J. M. Stewart; 4. Algebraic approachs to the characteristic initial value problem in general relativity Jõrg Frauendiener; 5. On hyperboidal hypersurfaces Helmut Friedrich; 6. The initial value problem on null cones J. A. Vickers; 7. Introduction to dual-null dynamics S. A. Hayward; 8. On colliding plane wave space-times J. B. Griffiths; 9. Boundary conditions for the momentum constraint Niall O Murchadha; 10. On the choice of matter model in general relativity A. D. Rendall; 11. A mathematical approach to numerical relativity J. W. Barrett; 12. Making sense of the effects of rotation in general relativity J. C. Miller; 13. Stability of charged boson stars and catastrophe theory Franz E. Schunck, Fjodor V. Kusmartsev and Eckehard W. Mielke; Part II. Practical Approaches: 14. Numerical asymptotics R. Gómez and J. Winicour; 15. Instabilities in rapidly rotating polytropes Scott C. Smith and Joan M. Centrella; 16. Gravitational radiation from coalescing binary neutron stars Ken-Ichi Oohara and Takashi Nakamura; 17. 'Critical' behaviour in massless scalar field collapse M. W. Choptuik; 18. Goudunov-type methods applied to general relativistic gravitational collapse José Ma. Ibánez, José Ma. Martí, Juan A. Miralles and J. V. Romero; 19. Astrophysical sources of gravitational waves and neutrinos Silvano Bonazzola, Eric Gourgoulhon, Pawel Haensel and Jean-Alain Marck; 20. Gravitational radiation from triaxial core collapse Jean-Alain Marck and Silvano Bonazzola; 21. A vacuum fully relativistic 3D numerical code C. Bona and J. Massó; 22. Solution of elliptic equations in numerical relativity using multiquadrics M. R. Dubal, S. R. Oliveira and R. A. Matzner; 23

  8. An evolutionary approach

    NASA Astrophysics Data System (ADS)

    Healy, Thomas J.

    1993-04-01

    The paper describes an evolutionary approach to the development of aerospace systems, represented by the introduction of integrated product teams (IPTs), which are now used at Rockwell's Space Systems Division on all new programs and are introduced into existing projects after demonstrations of increases in quality and reductions in cost and schedule due to IPTs. Each IPT is unique and reflects its own program and lasts for the life of the program. An IPT includes customers, suppliers, subcontractors, and associate contractors, and have a charter, mission, scope of authority, budget, and schedule. Functional management is responsible for the staffing, training, method development, and generic technology development.

  9. Engineering approaches to biomanipulation.

    PubMed

    Desai, Jaydev P; Pillarisetti, Anand; Brooks, Ari D

    2007-01-01

    This article presents a review on the existing techniques for manipulating biological cells. Because biomanipulation involves a wide range of disciplines, from biology to engineering, we concentrate on some of the key methodologies that would result in an efficient biomanipulation system. Some of the key methodologies discussed in this article for cell manipulation relate to the use of magnetics, microelectromechanical systems (MEMS)-based approaches, optics, electric field, and mechanical techniques. Recent advances in engineering have allowed researchers worldwide to address the problems arising from conventional manipulation techniques. This paper assimilates significance and limitations of biomanipulation techniques described in the literature. PMID:17362196

  10. Cognitive approaches to emotions.

    PubMed

    Oatley, Keith; Johnson-Laird, P N

    2014-03-01

    Cognitive approaches offer clear links between how emotions are thought about in everyday life and how they are investigated psychologically. Cognitive researchers have focused on how emotions are caused when events or other people affect concerns and on how emotions influence processes such as reasoning, memory, and attention. Three representative cognitive theories of emotion continue to develop productively: the action-readiness theory, the core-affect theory, and the communicative theory. Some principles are common to them and divergences can be resolved by future research. Recent explanations have included how emotions structure social relationships, how they function in psychological illnesses, and how they are central to music and fiction. PMID:24389368

  11. New approaches for immunosuppression

    SciTech Connect

    Eiseman, B.; Hansbrough, J.; Weil, R.

    1980-01-01

    New approaches for experimental immunosuppression have been reviewed. These include the following: (1) cyclosporin A, a metabolite from fungus that suppresses multiplying but not resting T and B lymphocytes and can be used in pulsed manner with interspersed drug-free periods; (2) total lymphoid irradiation (transplantation tolerance in rats has been achieved by pretransplant radiation); (3) thoracic duct drainage, which is being revived following its demonstrated effectiveness in the treatment of some autoimmune diseases; (4) hyperbaric oxygen (HBOX). We have found that HBOX 2 1/2 ATA for five hours daily depresses cell-mediated immunity in mice and that this can be reversed by intravenous administration of autologous macrophages.

  12. Avenue of approach generation

    SciTech Connect

    Powell, D.R.; Storm, G.

    1988-01-01

    Los Alamos National Laboratory is conducting research on developing a dynamic planning capability within an Army corps level combat simulation. Central to this research is the development of a computer based ability to ''understand'' terrain and how it is used in military planning. Such a capability demands data structures that adequately represent terrain features used in the planning process. These features primarily relate to attributes of mobility and visibility. Mobility concepts are abstracted to networks of mobility corridors. Notions of visibility are, for the purposes of planning, incorporated into the definition of key terrain. Prior work at Los Alamos has produced algorithms to generate mobility corridors from digitized terrain data. Mobility corridors, by definition, are the building blocks for avenues of approach, and the latter are the context in which key terrain is defined. The purpose of this paper is to describe recent work in constructing avenues of approach, characterization of avenues using summary characteristics, and their role in military planning. 7 refs., 4 figs., 1 tab.

  13. Modular Approach to Spintronics

    PubMed Central

    Camsari, Kerem Yunus; Ganguly, Samiran; Datta, Supriyo

    2015-01-01

    There has been enormous progress in the last two decades, effectively combining spintronics and magnetics into a powerful force that is shaping the field of memory devices. New materials and phenomena continue to be discovered at an impressive rate, providing an ever-increasing set of building blocks that could be exploited in designing transistor-like functional devices of the future. The objective of this paper is to provide a quantitative foundation for this building block approach, so that new discoveries can be integrated into functional device concepts, quickly analyzed and critically evaluated. Through careful benchmarking against available theory and experiment we establish a set of elemental modules representing diverse materials and phenomena. These elemental modules can be integrated seamlessly to model composite devices involving both spintronic and nanomagnetic phenomena. We envision the library of modules to evolve both by incorporating new modules and by improving existing modules as the field progresses. The primary contribution of this paper is to establish the ground rules or protocols for a modular approach that can build a lasting bridge between materials scientists and circuit designers in the field of spintronics and nanomagnetics. PMID:26066079

  14. Approaches to robustness

    NASA Astrophysics Data System (ADS)

    Cox, Henry; Heaney, Kevin D.

    2003-04-01

    The term robustness in signal processing applications usually refers to approaches that are not degraded significantly when the assumptions that were invoked in defining the processing algorithm are no longer valid. Highly tuned algorithms that fall apart in real-world conditions are useless. The classic example is super-directive arrays of closely spaced elements. The very narrow beams and high directivity could be predicted under ideal conditions, could not be achieved under realistic conditions of amplitude, phase and position errors. The robust design tries to take into account the real environment as part of the optimization problem. This problem led to the introduction of the white noise gain constraint and diagonal loading in adaptive beam forming. Multiple linear constraints have been introduced in pursuit of robustness. Sonar systems such as towed arrays operate in less than ideal conditions, making robustness a concern. A special problem in sonar systems is failed array elements. This leads to severe degradation in beam patterns and bearing response patterns. Another robustness issue arises in matched field processing that uses an acoustic propagation model in the beamforming. Knowledge of the environmental parameters is usually limited. This paper reviews the various approaches to achieving robustness in sonar systems.

  15. Common approaches for adolescents.

    PubMed

    1998-01-01

    A South-South program organized by JOICFP provided an excellent opportunity for the exchange of experiences in the field of adolescent reproductive health (RH) between Mexico and the Philippines. Alfonso Lopez Juarez, executive director, Mexican Foundation for Family Planning (MEXFAM), shared MEXFAM's experiences with field personnel and GO-NGO representatives related to JOICFP's RH-oriented project in the Philippines while in the country from November 16 to 21. The program was also effective for identifying common issues and effective approaches to adolescent health issues and communicating with youth on RH and sexual health. The exchange was supported by the Hoken Kaikan Foundation and organized by JOICFP in collaboration with UNFPA-Manila and the Commission on Population (POPCOM). Lopez shared some of the lessons of MEXFAM's decade-long Gente Joven IEC program on adolescent health with GO and NGO representatives at a forum held on November 18. The event was opened by Dr. Carmencita Reodica, secretary, Department of Health (DOH). He then moved to the project sites of Balayan and Malvar municipalities of Batangas Province, where he spoke with field staff and demonstrated MEXFAM's approach in classroom situations with young people. Lopez also observed various adolescent activities such as group work with peer facilitators. "I am pleased that we can share some applicable experiences and learn from each other's projects," commented Lopez. PMID:12348336

  16. Breakfast: a multidisciplinary approach

    PubMed Central

    2013-01-01

    Background The role of breakfast as an essential part of an healthy diet has been only recently promoted even if breakfast practices were known since the Middle Age. The growing scientific evidences on this topic are extremely sector-based nevertheless breakfast could be regarded from different point of views and from different expertises. This approach, that take into account history, sociology, anthropology, medicine, psychology and pedagogy, is useful to better understand the value of this meal in our culture. The aim of this paper was to analyse breakfast-related issues based on a multidisciplinary approach with input by specialists from different fields of learning. Discussion Breakfast is now recommended as part of a diet because it is associated with healthier macro- and micronutrient intakes, body mass index and lifestyle. Moreover recent studies showed that breakfast improves cognitive function, intuitive perception and academic performance. Research demonstrates the importance of providing breakfast not only to children but in adults and elderly too. Although the important role breakfast plays in maintaining the health, epidemiological data from industrialised countries reveal that many individuals either eat a nutritionally unhealthy breakfast or skip it completely. Summary The historical, bio-psychological and educational value of breakfast in our culture is extremely important and should be recognized and stressed by the scientific community. Efforts should be done to promote this practice for the individual health and well-being. PMID:23842429

  17. Pharmacogenetics approach to therapeutics.

    PubMed

    Koo, Seok Hwee; Lee, Edmund Jon Deoon

    2006-01-01

    1. Pharmacogenetics refers to the study of genetically controlled variations in drug response. Functional variants caused by single nucleotide polymorphisms (SNPs) in genes encoding drug-metabolising enzymes, transporters, ion channels and drug receptors have been known to be associated with interindividual and interethnic variation in drug response. Genetic variations in these genes play a role in influencing the efficacy and toxicity of medications. 2. Rapid, precise and cost-effective high-throughput technological platforms are essential for performing large-scale mutational analysis of genetic markers involved in the aetiology of variable responses to drug therapy. 3. The application of a pharmacogenetics approach to therapeutics in general clinical practice is still far from being achieved today owing to various constraints, such as limited accessibility of technology, inadequate knowledge, ambiguity of the role of variants and ethical concerns. 4. Drug actions are determined by the interplay of several genes encoding different proteins involved in various biochemical pathways. With rapidly emerging SNP discovery technological platforms and widespread knowledge on the role of SNPs in disease susceptibility and variability in drug response, the pharmacogenetics approach to therapeutics is anticipated to take off in the not-too-distant future. This will present profound clinical, economic and social implications for health care. PMID:16700889

  18. Coordinated Parallel Runway Approaches

    NASA Technical Reports Server (NTRS)

    Koczo, Steve

    1996-01-01

    The current air traffic environment in airport terminal areas experiences substantial delays when weather conditions deteriorate to Instrument Meteorological Conditions (IMC). Expected future increases in air traffic will put additional pressures on the National Airspace System (NAS) and will further compound the high costs associated with airport delays. To address this problem, NASA has embarked on a program to address Terminal Area Productivity (TAP). The goals of the TAP program are to provide increased efficiencies in air traffic during the approach, landing, and surface operations in low-visibility conditions. The ultimate goal is to achieve efficiencies of terminal area flight operations commensurate with Visual Meteorological Conditions (VMC) at current or improved levels of safety.

  19. Engineering students' sustainability approaches

    NASA Astrophysics Data System (ADS)

    Haase, S.

    2014-05-01

    Sustainability issues are increasingly important in engineering work all over the world. This article explores systematic differences in self-assessed competencies, interests, importance, engagement and practices of newly enrolled engineering students in Denmark in relation to environmental and non-environmental sustainability issues. The empirical base of the article is a nation-wide, web-based survey sent to all newly enrolled engineering students in Denmark commencing their education in the fall term 2010. The response rate was 46%. The survey focused on a variety of different aspects of what can be conceived as sustainability. By means of cluster analysis, three engineering student approaches to sustainability are identified and described. The article provides knowledge on the different prerequisites of engineering students in relation to the role of sustainability in engineering. This information is important input to educators trying to target new engineering students and contribute to the provision of engineers equipped to meet sustainability challenges.

  20. Neuroblastoma: A neurochemical approach

    SciTech Connect

    Schor, N.F. )

    1991-07-01

    Neuroblastoma is among the most common malignancies of childhood. Despite greatly improved therapy for some pediatric tumors, the prognosis for children with metastatic neuroblastoma has not changed significantly in the past 10 years. With conventional chemotherapy, radiation therapy, and surgery, children with metastatic neuroblastoma have a 20% long-term survival rate. The authors describe here approaches to neuroblastoma that target its neuronal characteristics. On the one hand, the neurotransmitter receptors on the surface of the neuroblastoma cells and, on the other hand, specific isozymes that distinguish neuroblastoma cells from their normal counterparts are the focus of these experimental therapies. In the former case, specificity for tumor cells is effected by (1) selective protection of normal neuronal elements from toxicity, or (2) selective potentiation of toxicity for neural tumor cells. It is hoped that these strategies will be generalizable to other neural crest-derived tumors. 32 references.

  1. Therapeutic approaches for shankopathies.

    PubMed

    Wang, Xiaoming; Bey, Alexandra L; Chung, Leeyup; Krystal, Andrew D; Jiang, Yong-Hui

    2014-02-01

    Despite recent advances in understanding the molecular mechanisms of autism spectrum disorders (ASD), the current treatments for these disorders are mostly focused on behavioral and educational approaches. The considerable clinical and molecular heterogeneity of ASD present a significant challenge to the development of an effective treatment targeting underlying molecular defects. Deficiency of SHANK family genes causing ASD represent an exciting opportunity for developing molecular therapies because of strong genetic evidence for SHANK as causative genes in ASD and the availability of a panel of Shank mutant mouse models. In this article, we review the literature suggesting the potential for developing therapies based on molecular characteristics and discuss several exciting themes that are emerging from studying Shank mutant mice at the molecular level and in terms of synaptic function. PMID:23536326

  2. Modelling approaches for angiogenesis.

    PubMed

    Taraboletti, G; Giavazzi, R

    2004-04-01

    The development of a functional vasculature within a tumour is a requisite for its growth and progression. This fact has led to the design of therapies directed toward the tumour vasculature, aiming either to prevent the formation of new vessels (anti-angiogenic) or to damage existing vessels (vascular targeting). The development of agents with different mechanisms of action requires powerful preclinical models for the analysis and optimization of these therapies. This review concerns 'classical' assays of angiogenesis in vitro and in vivo, recent approaches to target identification (analysis of gene and protein expression), and the study of morphological and functional changes in the vasculature in vivo (imaging techniques). It mainly describes assays designed for anti-angiogenic compounds, indicating, where possible, their application to the study of vascular-targeting agents. PMID:15120043

  3. Editorial: Approaching 125.

    PubMed

    Goodman, Sherryl

    2012-02-01

    With this issue, beginning Volume 121, the editorial team shifts from the strong leadership of David Watson to a team under my direction. Approaching 125 years of publication, the Journal of Abnormal Psychology has earned its place as the preeminent outlet for research in psychopathology. With gratitude to the newly assembled team of associate editors (AEs), consulting editors, and ad hoc reviewers, I look forward to guiding the journal through this next term. Nine well-respected scholars have agreed to serve as AEs: Timothy Brown, Laurie Chassin, Jeff Epstein, Jutta Joormann, Pamela Keel, Kate Keenan, Scott Lilienfeld, Angus MacDonald, and Michael Young. The new team is dedicated to working tirelessly to maintain and enhance the journal's esteemed tradition of excellence. Given the well-established strengths of the journal, I will not suggest any fundamental changes. PMID:22329705

  4. Approaching the new reality

    NASA Technical Reports Server (NTRS)

    Diaz, Al V.

    1993-01-01

    I'm very pleased to be here and to have this opportunity to discuss with you what I view as the current challenges in space science. Today, NASA finds itself at a major crossroads. We are in the process of moving from one era in our existence into another. As we continue to launch important science missions, we are simultaneously changing the way we do business, in a very fundamental way. We are again focusing on more frequent access to space through smaller, less costly missions. We are again focusing on NASA's role as a source of technological advancement within the U.S. economy. And we are returning to the leaner, more flexible approach to managing our projects. In short, NASA has embarked on a new journey, and a challenging journey it will be.

  5. Approaching the new reality

    NASA Astrophysics Data System (ADS)

    Diaz, Al V.

    I'm very pleased to be here and to have this opportunity to discuss with you what I view as the current challenges in space science. Today, NASA finds itself at a major crossroads. We are in the process of moving from one era in our existence into another. As we continue to launch important science missions, we are simultaneously changing the way we do business, in a very fundamental way. We are again focusing on more frequent access to space through smaller, less costly missions. We are again focusing on NASA's role as a source of technological advancement within the U.S. economy. And we are returning to the leaner, more flexible approach to managing our projects. In short, NASA has embarked on a new journey, and a challenging journey it will be.

  6. An environmental approach

    SciTech Connect

    Geerling, C.

    1996-11-01

    The Shell Petroleum Development Company is operating in southern Nigeria in the delta of the Niger River. This delta covers an area 70,000 square kin of coastal ridge barriers, mangroves, freshwater swamp forest and lowland rain forests. Over the past decades considerable changes has occurred through coastal zone modifications, upstream urban and hydrological infrastructure, deforestation, agriculture, fisheries, industrial development, oil operation, as well as demographic changes. The problems associated with these changes are: (1) over-exploitation of renewable natural resources and breakdown of traditional management structures; (2) impact from industry such as pollution and physical changes, and (3) a perception of lack of social and economic equity. This paper describes approaches to help counteract theses problems.

  7. Children and Complementary Health Approaches

    MedlinePlus

    ... Ewsichek What’s the Bottom Line? How much do we know about complementary health approaches for children? We ... about their effects and safety. 1 What do we know about the effectiveness of complementary health approaches ...

  8. Alternative approaches to population structure.

    PubMed

    Morton, N E

    1995-01-01

    There are three approaches to DNA identification: tectonic, halieutic and icarian, of which the tectonic is sensible, the halieutic impractical, and the icarian idiotic. The rationale and consequences of these approaches are detailed. PMID:7607451

  9. Television Criticism: A Multifarious Approach.

    ERIC Educational Resources Information Center

    Oseguera, A. Anthony

    Recognizing the need for a multifarious approach to television, this paper provides the reader with the following multidimensional approaches to television criticism: rhetorical, dramatic, literary, cinematic, content analysis, myth, linguistics, semiotics, phenomenalism, phenomenology, interpersonal communication, public relations, image,…

  10. Cancer and Complementary Health Approaches

    MedlinePlus

    ... Legislation Advisory Council Job Opportunities All About NCCIH Health Topics A-Z # A B C D E ... from NCI at www.cancer.gov . About Complementary Health Approaches Complementary health approaches are a group of ...

  11. Approaching attometer laser vibrometry

    SciTech Connect

    Rembe, Christian; Kadner, Lisa; Giesen, Moritz

    2014-05-27

    The heterodyne two-beam interferometer has been proven to be the optimal solution for laser-Doppler vibrometry regarding accuracy and signal robustness. The theoretical resolution limit for a two-beam interferometer of laser class 3R (up to 5 mW visible measurement-light) is in the regime of a few femtometer per square-root Hertz and well suited to study vibrations in microstructures. However, some new applications of RF-MEM resonators, nanostructures, and surface-nano-defect detection require resolutions beyond that limit. The resolution depends only on the noise and the sensor sensitivity to specimen displacements. The noise is already defined in nowadays systems by the quantum nature of light for a properly designed optical sensor and more light would lead to an inacceptable influence like heating of a very tiny structure. Thus, noise can only be improved by squeezed-light techniques which require a negligible loss of measurement light which is impossible for almost all technical measurement tasks. Thus, improving the sensitivity is the only possible path which could make attometer laser vibrometry possible. Decreasing the measurement wavelength would increase the sensitivity but would also increase the photon shot noise. In this paper, we discuss an approach to increase the sensitivity by assembling an additional mirror between interferometer and specimen to form an optical cavity. A detailed theoretical analysis of this setup is presented and we derive the resolution limit, discuss the main contributions to the uncertainty budget, and show a first experiment proving the sensitivity amplification of our approach.

  12. Neptune - closest approach

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Voyager spacecraft took this picture after closest approach to Neptune on Aug. 25 1989, using the clear filter of the wide-angle camera with an exposure time of 255 seconds. The view back towards Neptune at a phase angle of 135 degrees found the two known rings to be five to 10 times brighter than seen in backscattering during Voyager approach at much lower phase angle. This brightness increase implies a large percentage of microscopic particles within the rings. Although the dominant arc-like clump of the outer ring is not seen here, the inner ring appears brighter than the outer ring at the longitudes seen in this image. A faint sheet of material is also revealed that extends from the faint ring at a radius of 53,200 kilometers(33,000 miles). A new and even fainter ring was discovered in this image at about 41,000 kilometers (25,400 miles), seen running from the lower left corner to about one-third the way across the top of the frame. This ring is quite broad, about 2,500 kilometers (1,550 miles) in radial width. In contrast to the two previously discovered rings, this feature is quite diffuse and has no well defined radial boundaries. The Voyager imaging experiment has now detected ring material in all of the radial regions in which it has been detected by groundbased stellar occultation experiments. The Voyager spacecraft was 720,000 kilometers (446,400 miles) from Neptune at the time of this exposure. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.

  13. Approaches to Multicultural Curriculum Reform.

    ERIC Educational Resources Information Center

    Banks, James A.

    1990-01-01

    Discusses the pros and cons of the contributions of ethnic additive, transformation, decision-making, and social action approaches to multicultural curriculum development. Suggests that movement from a mainstream-centric approach to social action approach is gradual and cumulative. (GG)

  14. A comparison of various artificial intelligence approaches performance for estimating suspended sediment load of river systems: a case study in United States.

    PubMed

    Olyaie, Ehsan; Banejad, Hossein; Chau, Kwok-Wing; Melesse, Assefa M

    2015-04-01

    Accurate and reliable suspended sediment load (SSL) prediction models are necessary for planning and management of water resource structures. More recently, soft computing techniques have been used in hydrological and environmental modeling. The present paper compared the accuracy of three different soft computing methods, namely, artificial neural networks (ANNs), adaptive neuro-fuzzy inference system (ANFIS), coupled wavelet and neural network (WANN), and conventional sediment rating curve (SRC) approaches for estimating the daily SSL in two gauging stations in the USA. The performances of these models were measured by the coefficient of correlation (R), Nash-Sutcliffe efficiency coefficient (CE), root-mean-square error (RMSE), and mean absolute percentage error (MAPE) to choose the best fit model. Obtained results demonstrated that applied soft computing models were in good agreement with the observed SSL values, while they depicted better results than the conventional SRC method. The comparison of estimation accuracies of various models illustrated that the WANN was the most accurate model in SSL estimation in comparison to other models. For example, in Flathead River station, the determination coefficient was 0.91 for the best WANN model, while it was 0.65, 0.75, and 0.481 for the best ANN, ANFIS, and SRC models, and also in the Santa Clara River, amounts of this statistical criteria was 0.92 for the best WANN model, while it was 0.76, 0.78, and 0.39 for the best ANN, ANFIS, and SRC models, respectively. Also, the values of cumulative suspended sediment load computed by the best WANN model were closer to the observed data than the other models. In general, results indicated that the WANN model could satisfactorily mimic phenomenon, acceptably estimate cumulative SSL, and reasonably predict peak SSL values. PMID:25787167

  15. A pre-calibration approach to selecting optimum inputs for hydrological models in data-scarce regions: a case study in Jordan

    NASA Astrophysics Data System (ADS)

    Tarawneh, Esraa; Bridge, Jonathan; Macdonald, Neil

    2016-04-01

    This study reports a pre-calibration methodology to select optimum inputs to hydrological models in dryland environments, demonstrated on the semi-arid Wala catchment, Jordan (1743 km2). The Soil and Water Assessment Tool (SWAT) is used to construct eighteen model scenarios combining three land-use, two soil and three weather datasets spanning 1979 - 2002. Weather datasets include locally-recorded precipitation and temperature data and global reanalysis data products. Soil data comprise a high-resolution map constructed from national soil survey data and a significantly lower-resolution global soil map. Landuse maps are obtained from global and local sources; with some modifications applied to the latter using available descriptive landuse information. Variability in model performance arising from using different dataset combinations is assessed by testing uncalibrated model outputs against discharge and sediment load data using r2, Nash-Sutcliffe Efficiency (NSE), RSR and PBIAS. A ranking procedure identifies best-performing input data combinations and trends among the scenarios. In the case of Wala, Jordan, global weather inputs yield considerable improvements on discontinuous local datasets; conversely, local high-resolution soil mapping data perform considerably better than globally-available soil data. NSE values vary from 0.56 to -12 and 0.79 to -85 for best and worst-performing scenarios against observed discharge and sediment data respectively. Full calibration remains an essential step prior to model application. However, the methodology presented provides a transparent, transferable approach to selecting the most robust suite of input data and hence minimising structural biases in model performance arising when calibration proceeds from low-quality initial assumptions. In regions where data are scarce, their quality is unregulated and survey resources are limited, such methods are essential in improving confidence in models which underpin critical water

  16. Development of regionalisation procedures using a multi-model approach for flow simulation in an ungauged catchment

    NASA Astrophysics Data System (ADS)

    Goswami, M.; O'Connor, K. M.; Bhattarai, K. P.

    2007-02-01

    SummaryFlow simulation in ungauged catchments is presently regarded as one of the most challenging tasks in surface water hydrology. Many of the ungauged catchments are located in the headwaters of rivers in mountainous regions of the world having enormous potential for sustainable water resource development. However, due to inaccessibility, rugged and inhospitable terrain, and historical lack of foresight concerning the need to have these headwaters adequately gauged, their potential is not readily realizable. Many downstream sites also suffer from non-availability of site-specific data as even in countries having extensive networks of gauged stations data may not be available at sites where these are most needed. As predictive tools for water resources, water quality, natural hazard mitigation and water availability assessment are generally data-driven, the lack of adequate hydrometric records poses difficult problems for planners, engineers, managers, and stake-holders alike. In this study, a methodology is developed for flow simulation in ungauged catchments using a regionalisation and multi-model approach involving a suite of rainfall-runoff models and combination techniques. Daily observed hydrometeorological data for 12 French catchments are used for illustrating the procedures. Following a preliminary investigation of the regional homogeneity of that group of catchments, three regional flow simulation techniques are applied. Although all 12 catchments are gauged, initially each catchment is successively considered as being ungauged for the purpose of flow simulation in that catchment, their actual discharges being subsequently used for evaluating the performance of the flow estimation procedures for the catchment. The Nash-Sutcliffe efficiency index ( R2) is used for assessing and ranking the relative performances of the regionalisation-model couples to identify the most appropriate couple for the region. The final step of applying that couple to a truly

  17. Hydrologic Model Development and Calibration: Contrasting a Single- and Multi-Objective Approach for Comparing Model Performance

    NASA Astrophysics Data System (ADS)

    Asadzadeh, M.; Maclean, A.; Tolson, B. A.; Burn, D. H.

    2009-05-01

    Hydrologic model calibration aims to find a set of parameters that adequately simulates observations of watershed behavior, such as streamflow, or a state variable, such as snow water equivalent (SWE). There are different metrics for evaluating calibration effectiveness that involve quantifying prediction errors, such as the Nash-Sutcliffe (NS) coefficient and bias evaluated for the entire calibration period, on a seasonal basis, for low flows, or for high flows. Many of these metrics are conflicting such that the set of parameters that maximizes the high flow NS differs from the set of parameters that maximizes the low flow NS. Conflicting objectives are very likely when different calibration objectives are based on different fluxes and/or state variables (e.g., NS based on streamflow versus SWE). One of the most popular ways to balance different metrics is to aggregate them based on their importance and find the set of parameters that optimizes a weighted sum of the efficiency metrics. Comparing alternative hydrologic models (e.g., assessing model improvement when a process or more detail is added to the model) based on the aggregated objective might be misleading since it represents one point on the tradeoff of desired error metrics. To derive a more comprehensive model comparison, we solved a bi-objective calibration problem to estimate the tradeoff between two error metrics for each model. Although this approach is computationally more expensive than the aggregation approach, it results in a better understanding of the effectiveness of selected models at each level of every error metric and therefore provides a better rationale for judging relative model quality. The two alternative models used in this study are two MESH hydrologic models (version 1.2) of the Wolf Creek Research basin that differ in their watershed spatial discretization (a single Grouped Response Unit, GRU, versus multiple GRUs). The MESH model, currently under development by Environment

  18. Hydrological budget of Lake Chad: assessment of lake-groundwater interaction by coupling Bayesian approach and chemical budget

    NASA Astrophysics Data System (ADS)

    Bouchez, Camille; Goncalves, Julio; Deschamps, Pierre; Seidel, Jean-Luc; Doumnang, Jean-Claude; Sylvestre, Florence

    2014-05-01

    Estimation of lake-groundwater interactions is a crucial step to constrain water balance of lacustrine and aquifer systems. Located in the Sahel, the Lake Chad is at the center of an endorheic basin of 2,5.106 km2. One of the most remarkable features of this terminal lake is that, despite the semi-arid context and high evaporation rates of the area, its waters are fresh. It is proposed in the literature that the solutes are evacuated in the underlying quaternary aquifer bearing witness to the importance of surface water and groundwater exchanges for the chemical regulation of the lake. The water balance of this system is still not fully understood. The respective roles of evaporation versus infiltration into the quaternary aquifer are particularly under constrained. To assess lake-groundwater flows, we used the previous conceptual hydrological model of the lake Chad proposed by Bader et al. (Hydrological Sciences Journal, 2011). This model involves six parameters including infiltration rate. A probabilistic inversion of parameters, based on an exploration of the parameters space through a Metropolis algorithm (a Monte Carlo Markov Chain method), allows the construction of an a posteriori Probability Density Function of each parameter yielding to the best fits between observed lake levels and simulated. Then, a chemical budget of a conservative element, such as chloride, is introduced in the water balance model using the optimal parameters resulting from the Bayesian inverse approach. The model simulates lake level and chloride concentration variations of lake Chad from 1956 up to 2008. Simulated lake levels are in overall agreement with the observations, with a Nash-Sutcliffe efficiency coefficient above 0.94 for all sets of parameters retained. The infiltration value, obtained by such probabilistic inversion approach, accounts for 120±20 mm/yr, representing 5% of the total outputs of the lake. However, simulated chloride concentrations are overestimated in

  19. [Hypercholesterolemia: a therapeutic approach].

    PubMed

    Moráis López, A; Lama More, R A; Dalmau Serra, J

    2009-05-01

    High blood cholesterol levels represent an important cardiovascular risk factor. Hypercholesterolemia is defined as levels of total cholesterol and low-density lipoprotein cholesterol above 95th percentile for age and gender. For the paediatric population, selective screening is recommended in children older than 2 years who are overweight, with a family history of early cardiovascular disease or whose parents have high cholesterol levels. Initial therapeutic approach includes diet therapy, appropriate physical activity and healthy lifestyle changes. Drug treatment should be considered in children from the age of 10 who, after having followed appropriate diet recommendations, still have very high LDL-cholesterol levels or moderately high levels with concomitant risk factors. In case of extremely high LDL-cholesterol levels, drug treatment should be taken into consideration at earlier ages (8 years old). Modest response is usually observed with bile acid-binding resins. Statins can be considered first-choice drugs, once evidence on their efficacy and safety has been shown. PMID:19427823

  20. Variational Approach to SAW

    NASA Astrophysics Data System (ADS)

    Burlatsky, Sergei F.; Reinhardt, S.; Lach; Ovchinnikov, Yu.

    1996-03-01

    A new variational technique is used to analyze both analytically and numerically the scaling behavior of Self Avoiding Walks. We present a set of lower bounds for the survival provability (the ratio of total number of self avoiding paths to total number of random paths) which is based on Jensen inequality. This set is generated by the hierarchy of different trial hamiltonians which correspond to: unconstrained random walk, mean field approximation, original Flory model and to a new approach which allows to vary independently the scales of fluctuations, corresponding to different path length scales. The D=2, D=3, and Darrow 4, cases are analyzed separately. The results of analytical variational procedure reproduce classical mean field exponents for small scales and Flory - type critical exponents for large scales, and present new estimates for the chemical potential of SAW. Possible generalizations to branching self avoiding paths are discussed. The numerical algorithm which is based on proposed trial hamiltonian might increase the efficiency with which the chemical potential and scaling properties of chain molecules with a finite number of discrete conformations can be computed. This work was supported in part by ONR Grant N00014-94-0647.

  1. Halitosis: the multidisciplinary approach

    PubMed Central

    Bollen, Curd ML; Beikler, Thomas

    2012-01-01

    Halitosis, bad breath or oral malodour are all synonyms for the same pathology. Halitosis has a large social and economic impact. For the majority of patients suffering from bad breath, it causes embarrassment and affects their social communication and life. Moreover, halitosis can be indicative of underlying diseases. Only a limited number of scientific publications were presented in this field until 1995. Ever since, a large amount of research is published, often with lack of evidence. In general, intraoral conditions, like insufficient dental hygiene, periodontitis or tongue coating are considered to be the most important cause (85%) for halitosis. Therefore, dentists and periodontologists are the first-line professionals to be confronted with this problem. They should be well aware of the origin, the detection and especially of the treatment of this pathology. In addition, ear–nose–throat-associated (10%) or gastrointestinal/endocrinological (5%) disorders may contribute to the problem. In the case of halitophobia, psychiatrical or psychological problems may be present. Bad breath needs a multidisciplinary team approach: dentists, periodontologists, specialists in family medicine, ear–nose–throat surgeons, internal medicine and psychiatry need to be updated in this field, which still is surrounded by a large taboo. Multidisciplinary bad breath clinics offer the best environment to examine and treat this pathology that affects around 25% of the whole population. This article describes the origin, detection and treatment of halitosis, regarded from the different etiological origins. PMID:22722640

  2. Combined approach for gynecomastia

    PubMed Central

    El-Sabbagh, Ahmed Hassan

    2016-01-01

    Background: Gynecomastia is a deformity of male chest. Treatment of gynecomastia varied from direct surgical excision to other techniques (mainly liposuction) to a combination of both. Skin excision is done according to the grade. In this study, experience of using liposuction adjuvant to surgical excision was described. Patients and methods: Between September 2012 and April 2015, a total of 14 patients were treated with liposuction and surgical excision through a periareolar incision. Preoperative evaluation was done in all cases to exclude any underlying cause of gynecomastia. Results: All fourteen patients were treated bilaterally (28 breast tissues). Their ages ranged between 13 and 33 years. Two patients were classified as grade I, and four as grade IIa, IIb or III, respectively. The first 3 patients showed seroma. Partial superficial epidermolysis of areola occurred in 2 cases. Superficial infection of incision occurred in one case and was treated conservatively. Conclusion: All grades of gynecomastia were managed by the same approach. Skin excision was added to a patient that had severe skin excess with limited activity and bad skin complexion. No cases required another setting or asked for 2nd opinion. PMID:26955509

  3. The Stepping Stone Approach

    NASA Astrophysics Data System (ADS)

    Brumfitt, A.

    Education is a profession in its own right. It has its own parameters, passions and language. Having the responsibility both of educare and educere, education has a focus of delivering specific factual knowledge whilst drawing out the creative mind. Space Science is a special vehicle having the properties of both educare and educere. It has a magic and wonder that touches the very essence of an individual and his place in time and space; it offers the "wow" factor that all teachers strive for. Space Science is the wrapping paper for other elements in the curriculum, e.g. cross-curricula and skill-based activities, such as language development, creativity, etc. as well as the pure sciences which comprise of engineering, physics and other natural sciences from astronomy to chemistry to biology. Each of these spheres of influence are relevant from kindergarten to undergraduate studies and complement, and in addition support informal education in museums, science centers and the world of e-learning. ESA Science Education has devised the "Stepping Stone Approach" to maximize the greatest outreach to all education stakeholders in Europe. In this paper we illustrate how to best reach these target groups with very specific activities to trigger and sustain enthusiasm whilst supporting the pedagogical, subject content and skill-based needs of a prescribed curriculum.

  4. COMPRENDO: Focus and Approach

    PubMed Central

    Schulte-Oehlmann, Ulrike; Albanis, Triantafyllos; Allera, Axel; Bachmann, Jean; Berntsson, Pia; Beresford, Nicola; Carnevali, Daniela Candia; Ciceri, Francesca; Dagnac, Thierry; Falandysz, Jerzy; Galassi, Silvana; Hala, David; Janer, Gemma; Jeannot, Roger; Jobling, Susan; King, Isabella; Klingmüller, Dietrich; Kloas, Werner; Kusk, Kresten Ole; Levada, Ramon; Lo, Susan; Lutz, Ilka; Oehlmann, Jörg; Oredsson, Stina; Porte, Cinta; Rand-Weaver, Marian; Sakkas, Vasilis; Sugni, Michela; Tyler, Charles; van Aerle, Ronny; van Ballegoy, Christoph; Wollenberger, Leah

    2006-01-01

    Tens of thousands of man-made chemicals are in regular use and discharged into the environment. Many of them are known to interfere with the hormonal systems in humans and wildlife. Given the complexity of endocrine systems, there are many ways in which endocrine-disrupting chemicals (EDCs) can affect the body’s signaling system, and this makes unraveling the mechanisms of action of these chemicals difficult. A major concern is that some of these EDCs appear to be biologically active at extremely low concentrations. There is growing evidence to indicate that the guiding principle of traditional toxicology that “the dose makes the poison” may not always be the case because some EDCs do not induce the classical dose–response relationships. The European Union project COMPRENDO (Comparative Research on Endocrine Disrupters—Phylogenetic Approach and Common Principles focussing on Androgenic/Antiandrogenic Compounds) therefore aims to develop an understanding of potential health problems posed by androgenic and antiandrogenic compounds (AACs) to wildlife and humans by focusing on the commonalities and differences in responses to AACs across the animal kingdom (from invertebrates to vertebrates). PMID:16818253

  5. A Game-Theoretical Approach to Multimedia Social Networks Security

    PubMed Central

    Liu, Enqiang; Liu, Zengliang; Shao, Fei; Zhang, Zhiyong

    2014-01-01

    The contents access and sharing in multimedia social networks (MSNs) mainly rely on access control models and mechanisms. Simple adoptions of security policies in the traditional access control model cannot effectively establish a trust relationship among parties. This paper proposed a novel two-party trust architecture (TPTA) to apply in a generic MSN scenario. According to the architecture, security policies are adopted through game-theoretic analyses and decisions. Based on formalized utilities of security policies and security rules, the choice of security policies in content access is described as a game between the content provider and the content requester. By the game method for the combination of security policies utility and its influences on each party's benefits, the Nash equilibrium is achieved, that is, an optimal and stable combination of security policies, to establish and enhance trust among stakeholders. PMID:24977226

  6. Endoscopic Endonasal Transsphenoidal Approach

    PubMed Central

    Cappabianca, Paolo; Alfieri, Alessandra; Colao, Annamaria; Ferone, Diego; Lombardi, Gaetano; de Divitiis, Enrico

    1999-01-01

    The outcome of endoscopic endonasal transsphenoidal surgery in 10 patients with pituitary adenomas was compared with that of traditional transnasal transsphenoidal approach (TTA) in 20 subjects. Among the 10 individuals subjected to “pure endoscopy,” 2 had a microadenoma, 1 an intrasellar macroadenoma, 4 had a macroadenoma with suprasellar expansion, 2 had a macroadenoma with supra-parasellar expansion, and 1 a residual tumor; 5 had acromegaly and 5 had a nonfunctioning adenoma (NFA). Among the patients subjected to TTA, 4 had a microadenoma, 2 had an intrasellar macroadenoma, 6 had a macroadenoma with suprasellar expansion, 4 had a macroadenoma with supra-parasellar expansion, and 4 had a residual tumor; 9 patients had acromegaly, 1 hyperprolactinemia, 1 Cushing's disease, and 9 a NFA. At the macroscopic evaluation, tumor removal was total (100%) after endoscopy in 9 patients and after TTA in 14 patients. Six months after surgery, magnetic resonance imaging (MRI) confirmed the total tumor removal in 21 of 23 patients (91.3%). Circulating growth hormone (GH) and insulin-like growth factor-I (IGF-I) significantly decreased 6 months after surgery in all 14 acromegalic patients: normalization of plasma IGF-I levels was obtained in 4 of 5 patients after the endoscopic procedure and in 4 of 9 patients after TTA. Before surgery, pituitary hormone deficiency was present in 14 out of 30 patients: pituitary function improved in 4 patients, remaining unchanged in the other 10 patients. Visual field defects were present before surgery in 4 patients, and improved in all. Early surgical results in the group of 10 patients who underwent endoscopic pituitary tumor removal were at least equivalent to those of standard TTA, with excellent postoperative course. Postsurgical hospital stay was significantly shorter (3.1 ± 0.4 vs. 6.2 ± 0.3 days, p < 0.001) after endoscopy as compared to TTA. ImagesFigure 1Figure 2 PMID:17171126

  7. Skull base approaches in neurosurgery

    PubMed Central

    2010-01-01

    The skull base surgery is one of the most demanding surgeries. There are different structures that can be injured easily, by operating in the skull base. It is very important for the neurosurgeon to choose the right approach in order to reach the lesion without harming the other intact structures. Due to the pioneering work of Cushing, Hirsch, Yasargil, Krause, Dandy and other dedicated neurosurgeons, it is possible to address the tumor and other lesions in the anterior, the mid-line and the posterior cranial base. With the transsphenoidal, the frontolateral, the pterional and the lateral suboccipital approach nearly every region of the skull base is exposable. In the current state many different skull base approaches are described for various neurosurgical diseases during the last 20 years. The selection of an approach may differ from country to country, e.g., in the United States orbitozygomaticotomy for special lesions of the anterior skull base or petrosectomy for clivus meningiomas, are found more frequently than in Europe. The reason for writing the review was the question: Are there keyhole approaches with which someone can deal with a vast variety of lesions in the neurosurgical field? In my opinion the different surgical approaches mentioned above cover almost 95% of all skull base tumors and lesions. In the following text these approaches will be described. These approaches are: 1) pterional approach 2) frontolateral approach 3) transsphenoidal approach 4) suboccipital lateral approach These approaches can be extended and combined with each other. In the following we want to enhance this philosophy. PMID:20602753

  8. Rapid chromatographic method to decipher distinct alterations in lipid classes in NAFLD/NASH

    PubMed Central

    Laggai, Stephan; Simon, Yvette; Ranssweiler, Theo; Kiemer, Alexandra K; Kessler, Sonja M

    2013-01-01

    AIM: To establish a simple method to quantify lipid classes in liver diseases and to decipher the lipid profile in p62/IMP2-2/IGF2BP2-2 transgenic mice. METHODS: Liver-specific overexpression of the insulin-like growth factor 2 mRNA binding protein p62/IMP2-2/IGF2BP2-2 was used as a model for steatosis. Steatohepatitis was induced by feeding a methionine-choline deficient diet. Steatosis was assessed histologically. For thin layer chromatographic analysis, lipids were extracted from freeze-dried tissues by hexane/2-propanol, dried, redissolved, and chromatographically separated by a two-solvent system. Dilution series of lipid standards were chromatographed, detected, and quantified. The detection was performed by either 2’,7’-dichlorofluoresceine or a sulfuric acid/ethanol mixture. RESULTS: Histological analyses confirmed steatosis and steatohepatitis development. The extraction, chromatographic, and detection method showed high inter-assay reproducibility and allowed quantification of the different lipid classes. The analyses confirmed an increase of triglycerides and phosphatidylethanolamine and a decrease in phosphatidylcholine in the methionine-choline deficient diet. The method was used for the first time to asses the lipid classes induced in the p62-overexpressing mouse model and showed a significant increase in all detected lipid species with a prominent increase of triglycerides by 2-fold. Interestingly, the ratio of phosphatidylcholine to phosphatidylethanolamine was decreased, as previously suggested as a marker in the progression from steatosis to steatohepatitis. CONCLUSION: The thin layer chromatography analysis allows a reliable quantification of lipid classes and provides detailed insight into the lipogenic effect of p62. PMID:24179615

  9. Potential of vetiver (Vetiveria zizanoides L. Nash) for phytoremediation of phenol.

    PubMed

    Singh, Sudhir; Melo, J S; Eapen, Susan; D'Souza, S F

    2008-11-01

    Aseptically grown Vetiveria zizanoides were evaluated for their potential for phytoremediation of phenol from Murashige and Skoog's liquid medium. Phenol was found to be completely removed from incubation medium at the end of 4 days by V. zizanoides plantlets, when medium was supplemented with 50 and 100 mg L(-1) phenol, while with 200, 500, and 1000 mg L(-1) of phenol, 89%, 76% and 70%, respectively, were removed. Phenol removal was found to be associated with inherent production of peroxidase and hydrogen peroxide. Coupled with H(2)O(2) formation, the levels of antioxidant enzymes like superoxide dismutase and peroxidase showed an enhancement when plants were exposed to phenol, whereas catalase levels initially showed a decline due to the utilization of H(2)O(2) by peroxidase for phenol oxidation. However, when peroxidase levels declined, there was an enhancement in catalase levels to minimize the presence of H(2)O(2) in the medium. Having confirmed that the removal of phenol was by V. zizanoides plantlets, in the next phase, micropropagated plantlets and well-developed plants grown in hydroponics were used under in vivo conditions to study the effect of phenol (200 mg L(-1)) on plant growth and reuse. Although plant growth was reduced in presence of phenol, the results of the reuse study indicated the possibility of plants getting adapted to phenol without any decline in potential for phenol remediation. PMID:18082265

  10. HPLC Quantification of Phenolic Acids from Vetiveria zizanioides (L.) Nash and Its Antioxidant and Antimicrobial Activity

    PubMed Central

    Prajna, Jha; Richa, Jindal; Dipjyoti, Chakraborty

    2013-01-01

    Extraction procedure was standardized and for the soluble, glycoside, and wall-bound fractions of phenolic acids from Vetiveria zizanioides. The water soluble alkaline extract which represents the cell wall-bound fraction contained the highest amount of phenolic acids (2.62 ± 1.2 μM/g fwt GA equivalents). Increased phenolic content in the cell wall indicates more lignin deposition which has an important role in plant defense and stress mitigation. Antioxidant property expressed as percentage TEAC value obtained by ABTS assay was correlated with the amount of phenolic acids and showed a Pearson's coefficient 0.988 (significant at 0.01 level). The compounds p-coumaric acid, p-dihydroxybenzoic acid, and ferulic acid were detected in the acidic extracts by HPLC analysis. The plant extracts exhibited considerable antimicrobial activity against tested bacterial and fungal strains. PMID:26555971

  11. Genus VIII. Kibdelosporangium Shearer, Colman, Ferrin, Nisbet and Nash 1986, 48

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The morphology, physiology, systematics, ecology, and natural products of the species that currently compose the actinobacterial genus Kibdelosporangium is presented. The phylogenetic position of the taxa within this genus, including Kibdelosporangium aridum subsp. aridum, Kibdelosporangium aridum ...

  12. Defining biocultural approaches to conservation.

    PubMed

    Gavin, Michael C; McCarter, Joe; Mead, Aroha; Berkes, Fikret; Stepp, John Richard; Peterson, Debora; Tang, Ruifei

    2015-03-01

    We contend that biocultural approaches to conservation can achieve effective and just conservation outcomes while addressing erosion of both cultural and biological diversity. Here, we propose a set of guidelines for the adoption of biocultural approaches to conservation. First, we draw lessons from work on biocultural diversity and heritage, social-ecological systems theory, integrated conservation and development, co-management, and community-based conservation to define biocultural approaches to conservation. Second, we describe eight principles that characterize such approaches. Third, we discuss reasons for adopting biocultural approaches and challenges. If used well, biocultural approaches to conservation can be a powerful tool for reducing the global loss of both biological and cultural diversity. PMID:25622889

  13. The narrative approach to personalisation

    NASA Astrophysics Data System (ADS)

    Conlan, Owen; Staikopoulos, Athanasios; Hampson, Cormac; Lawless, Séamus; O'keeffe, Ian

    2013-06-01

    This article describes the narrative approach to personalisation. This novel approach to the generation of personalised adaptive hypermedia experiences employs runtime reconciliation between a personalisation strategy and a number of contextual models (e.g. user and domain). The approach also advocates the late binding of suitable content and services to the generated personalised pathway resulting in an interactive composition that comprises services as well as content. This article provides a detailed definition of the narrative approach to personalisation and showcases the approach through the examination of two use-cases: the personalised digital educational games developed by the ELEKTRA and 80Days projects; and the personalised learning activities realised as part of the AMAS project. These use-cases highlight the general applicability of the narrative approach and how it has been applied to create a diverse range of real-world systems.

  14. A bottom-up approach to derive the closure relation for modelling hydrological fluxes at the watershed scale

    NASA Astrophysics Data System (ADS)

    Vannametee, Ekkamol; Karssenberg, Derek; Hendriks, Martin; Bierkens, Marc

    2014-05-01

    , potentially avoiding calibration. The Hortonain runoff closure relation is evaluated using field discharge observations from 16 km2 catchments in the French Alps. The catchments are disaggregated to 60 REWs. Scaling parameters for each REW are derived from the parameter library. Discharge is simulated from individual REWs, routed over the stream network, and summed at the catchment outlets to obtain the catchment-scale responses. The results show that our closure relation is capable of reproducing the observed hydrograph and discharge volume without calibration, i.e. Nash-Sutcliffe index up to 0.8, 10% errors in discharge volume. Our closure relation outperforms a simple lumped rainfall-runoff model that does not have scaling components. A brute-force calibration for an optimal local-scale REW observable (i.e. saturated hydraulic conductivity; Ks), using a constant pre-factor for all REWs, however significantly improves the prediction. The calibrated Ks values are comparable to the local-scale observations in the study catchment, implying that calibration may be unnecessary if the local-scale observable REW properties can be correctly estimated. The bottom-up approach for derivation of closure relation, including the parameter estimation scheme, in this study is robust and shows promising applicability for the REW-based models.

  15. Geometric approaches to mesh generation

    SciTech Connect

    Hoffmann, C.M.

    1995-12-31

    We review three approaches to mesh generation that axe based on analyzing and accounting for the geometric structure of the domain. In the first approach, due to Armstrong, the domain is partitioned into subdomains based on the medial-axis transform, a tool for analyzing spatial structures. In the second approach, due to Cox, the design history defines a geometric structure of the domain. The design primitives of that structure are meshed separately, and mesh overlap is accounted for by coupling equations. The third approach argues that mesh generation ought to be integrated into the shape design process, by meshing design features separately and resolving overlapping meshes by standard geometric computations.

  16. Anterolateral Approach to the Pilon.

    PubMed

    Hickerson, Lindsay E; Verbeek, Diederik O; Klinger, Craig E; Helfet, David L

    2016-08-01

    This video reviews the indications, surgical approach, and case examples of the anterolateral approach to a distal tibial plafond fracture. If this approach is used in a staged fashion, when the soft envelope is ready, it affords excellent visualization for fracture fixation through thick skin flaps. An associated article reviews a cohort of 44 mainly type C3 pilon injuries treated by 2 orthopaedic traumatologist using the anterolateral approach after staged external fixation. An anatomic or good fracture reduction was obtained in 41 fractures with 13.6% of patients undergoing a secondary surgical procedure for infection or nonunion. PMID:27441938

  17. Microbial Burden Approach : New Monitoring Approach for Measuring Microbial Burden

    NASA Technical Reports Server (NTRS)

    Venkateswaran, Kasthuri; Vaishampayan, Parag; Barmatz, Martin

    2013-01-01

    Advantages of new approach for differentiating live cells/ spores from dead cells/spores. Four examples of Salmonella outbreaks leading to costly destruction of dairy products. List of possible collaboration activities between JPL and other industries (for future discussion). Limitations of traditional microbial monitoring approaches. Introduction to new approach for rapid measurement of viable (live) bacterial cells/spores and its areas of application. Detailed example for determining live spores using new approach (similar procedure for determining live cells). JPL has developed a patented approach for measuring amount of live and dead cells/spores. This novel "molecular" method takes less than 5 to 7 hrs. compared to the seven days required using conventional techniques. Conventional "molecular" techniques can not discriminate live cells/spores among dead cells/spores. The JPL-developed novel method eliminates false positive results obtained from conventional "molecular" techniques that lead to unnecessary delay in the processing and to unnecessary destruction of food products.

  18. Exomars Mission Verification Approach

    NASA Astrophysics Data System (ADS)

    Cassi, Carlo; Gilardi, Franco; Bethge, Boris

    According to the long-term cooperation plan established by ESA and NASA in June 2009, the ExoMars project now consists of two missions: A first mission will be launched in 2016 under ESA lead, with the objectives to demonstrate the European capability to safely land a surface package on Mars, to perform Mars Atmosphere investigation, and to provide communi-cation capability for present and future ESA/NASA missions. For this mission ESA provides a spacecraft-composite, made up of an "Entry Descent & Landing Demonstrator Module (EDM)" and a Mars Orbiter Module (OM), NASA provides the Launch Vehicle and the scientific in-struments located on the Orbiter for Mars atmosphere characterisation. A second mission with it launch foreseen in 2018 is lead by NASA, who provides spacecraft and launcher, the EDL system, and a rover. ESA contributes the ExoMars Rover Module (RM) to provide surface mobility. It includes a drill system allowing drilling down to 2 meter, collecting samples and to investigate them for signs of past and present life with exobiological experiments, and to investigate the Mars water/geochemical environment, In this scenario Thales Alenia Space Italia as ESA Prime industrial contractor is in charge of the design, manufacturing, integration and verification of the ESA ExoMars modules, i.e.: the Spacecraft Composite (OM + EDM) for the 2016 mission, the RM for the 2018 mission and the Rover Operations Control Centre, which will be located at Altec-Turin (Italy). The verification process of the above products is quite complex and will include some pecu-liarities with limited or no heritage in Europe. Furthermore the verification approach has to be optimised to allow full verification despite significant schedule and budget constraints. The paper presents the verification philosophy tailored for the ExoMars mission in line with the above considerations, starting from the model philosophy, showing the verification activities flow and the sharing of tests

  19. Approaches to Teaching Foreign Languages.

    ERIC Educational Resources Information Center

    Hesse, M. G., Ed.

    Works by European and American educators from the Renaissance to the twentieth century are presented. A historical re-evaluation of foreign-language teaching combined with the scientific approach of modern linguistics can provide valuable insights for current teaching and learning approaches. Selections are presented from the writings of the…

  20. Cognitive Approaches to Automated Instruction.

    ERIC Educational Resources Information Center

    Regian, J. Wesley, Ed.; Shute, Valerie J., Ed.

    This book contains a snapshot of state-of-the-art research on the design of automated instructional systems. Selected cognitive psychologists were asked to describe their approach to instruction and cognitive diagnosis, the theoretical basis of the approach, its utility and applicability, and the knowledge engineering or task analysis methods…

  1. Systems Approach to Environmental Pollution.

    ERIC Educational Resources Information Center

    Chacko, George K., Ed.

    The objective of a two-day Symposium on Systems Approach to Environmental Pollution of the Operations Research Society of America at the 137th Annual Meeting of the American Association for the Advancement of Science, December 27-28, 1970 in Chicago, Illinois, was not to raise the litany of a systems approach as the answer to all environmental…

  2. A Systems Approach to Teaching.

    ERIC Educational Resources Information Center

    Kelly, Robert E.

    The systematic approach to teaching provides a method for the functional organization and development of instruction. This method applies to preparation of materials for classroom use, as well as for print and non-print media. Inputs to the systems approach include well defined objectives, analysis of the intended audience, special criteria…

  3. Alternatives in Education -- 54 Approaches.

    ERIC Educational Resources Information Center

    Jekel, Jerome R.; Johnson, Robert E.

    Fifty-four approaches identify ways by which students can learn, methods for teachers to employ, and approaches to a sequence of studies. A statement of philosophy notes the book's goal of providing a transition from individualized instruction to personalized instruction. The purpose, needs, philosophy and objectives of the open studies program…

  4. An Experimental Approach To… Everything!

    ERIC Educational Resources Information Center

    Orr, Taylor; Flowers, Jim

    2014-01-01

    The goal of formal education is student learning. By emphasizing experimentation in the classroom or lab, students learn about the results of a particular inquiry. But more importantly, they learn to refine their approach to learning by creating new knowledge rather than merely remembering what they have been told. An inquiry approach where…

  5. Personnel Selection: The Holistic Approach.

    ERIC Educational Resources Information Center

    Cooper, John F.; Garmon, John F.

    The recruitment, screening, and appointment of faculty and staff are vital steps towards institutional excellence. The holistic approach to hiring reviews every aspect of each candidate's qualifications from various points of view. The approach begins with the formation of a screening/search committee consisting of a representative group of…

  6. Engineering approaches to ecosystem restoration

    SciTech Connect

    Hayes, D.F.

    1998-07-01

    This proceedings CD ROM contains 127 papers on developing and evaluating engineering approaches to wetlands and river restoration. The latest engineering developments are discussed, providing valuable insights to successful approaches for river restoration, wetlands restoration, watershed management, and constructed wetlands for stormwater and wastewater treatment. Potential solutions to a wide variety of ecosystem concerns in urban, suburban, and coastal environments are presented.

  7. Mitochondrial biogenesis: pharmacological approaches.

    PubMed

    Valero, Teresa

    2014-01-01

    Organelle biogenesis is concomitant to organelle inheritance during cell division. It is necessary that organelles double their size and divide to give rise to two identical daughter cells. Mitochondrial biogenesis occurs by growth and division of pre-existing organelles and is temporally coordinated with cell cycle events [1]. However, mitochondrial biogenesis is not only produced in association with cell division. It can be produced in response to an oxidative stimulus, to an increase in the energy requirements of the cells, to exercise training, to electrical stimulation, to hormones, during development, in certain mitochondrial diseases, etc. [2]. Mitochondrial biogenesis is therefore defined as the process via which cells increase their individual mitochondrial mass [3]. Recent discoveries have raised attention to mitochondrial biogenesis as a potential target to treat diseases which up to date do not have an efficient cure. Mitochondria, as the major ROS producer and the major antioxidant producer exert a crucial role within the cell mediating processes such as apoptosis, detoxification, Ca2+ buffering, etc. This pivotal role makes mitochondria a potential target to treat a great variety of diseases. Mitochondrial biogenesis can be pharmacologically manipulated. This issue tries to cover a number of approaches to treat several diseases through triggering mitochondrial biogenesis. It contains recent discoveries in this novel field, focusing on advanced mitochondrial therapies to chronic and degenerative diseases, mitochondrial diseases, lifespan extension, mitohormesis, intracellular signaling, new pharmacological targets and natural therapies. It contributes to the field by covering and gathering the scarcely reported pharmacological approaches in the novel and promising field of mitochondrial biogenesis. There are several diseases that have a mitochondrial origin such as chronic progressive external ophthalmoplegia (CPEO) and the Kearns- Sayre syndrome (KSS

  8. Surgical approaches to the elbow.

    PubMed

    Cheung, Emilie V; Steinmann, Scott P

    2009-05-01

    Surgical exposures for complex injuries about the elbow are technically demanding because of the high density of neurologic, vascular, and ligamentous elements around the elbow. The posterior approaches (ie, olecranon osteotomy, triceps-reflecting, triceps-splitting, triceps-reflecting anconeus pedicle flap, paratricipital) include techniques used to navigate the area around the triceps tendon and anconeus muscle. These approaches may be extended to gain access to the entire joint. The ulnar nerve, the anterior and posterior capsules, and the coronoid process are addressed by means of a medial approach. Lateral approaches are useful in addressing pathology at the radial head, capitellum, coronoid process, and anterior and posterior capsules. These approaches may be combined to address complex pathology in the setting of fracture fixation, arthroplasty, and capsular release. PMID:19411644

  9. A multi-source satellite data approach for modelling Lake Turkana water level: calibration and validation using satellite altimetry data

    NASA Astrophysics Data System (ADS)

    Velpuri, N. M.; Senay, G. B.; Asante, K. O.

    2012-01-01

    Lake Turkana is one of the largest desert lakes in the world and is characterized by high degrees of inter- and intra-annual fluctuations. The hydrology and water balance of this lake have not been well understood due to its remote location and unavailability of reliable ground truth datasets. Managing surface water resources is a great challenge in areas where in-situ data are either limited or unavailable. In this study, multi-source satellite-driven data such as satellite-based rainfall estimates, modelled runoff, evapotranspiration, and a digital elevation dataset were used to model Lake Turkana water levels from 1998 to 2009. Due to the unavailability of reliable lake level data, an approach is presented to calibrate and validate the water balance model of Lake Turkana using a composite lake level product of TOPEX/Poseidon, Jason-1, and ENVISAT satellite altimetry data. Model validation results showed that the satellite-driven water balance model can satisfactorily capture the patterns and seasonal variations of the Lake Turkana water level fluctuations with a Pearson's correlation coefficient of 0.90 and a Nash-Sutcliffe Coefficient of Efficiency (NSCE) of 0.80 during the validation period (2004-2009). Model error estimates were within 10% of the natural variability of the lake. Our analysis indicated that fluctuations in Lake Turkana water levels are mainly driven by lake inflows and over-the-lake evaporation. Over-the-lake rainfall contributes only up to 30% of lake evaporative demand. During the modelling time period, Lake Turkana showed seasonal variations of 1-2 m. The lake level fluctuated in the range up to 4 m between the years 1998-2009. This study demonstrated the usefulness of satellite altimetry data to calibrate and validate the satellite-driven hydrological model for Lake Turkana without using any in-situ data. Furthermore, for Lake Turkana, we identified and outlined opportunities and challenges of using a calibrated satellite-driven water

  10. A multi-source satellite data approach for modelling Lake Turkana water level: Calibration and validation using satellite altimetry data

    USGS Publications Warehouse

    Velpuri, N.M.; Senay, G.B.; Asante, K.O.

    2012-01-01

    Lake Turkana is one of the largest desert lakes in the world and is characterized by high degrees of interand intra-annual fluctuations. The hydrology and water balance of this lake have not been well understood due to its remote location and unavailability of reliable ground truth datasets. Managing surface water resources is a great challenge in areas where in-situ data are either limited or unavailable. In this study, multi-source satellite-driven data such as satellite-based rainfall estimates, modelled runoff, evapotranspiration, and a digital elevation dataset were used to model Lake Turkana water levels from 1998 to 2009. Due to the unavailability of reliable lake level data, an approach is presented to calibrate and validate the water balance model of Lake Turkana using a composite lake level product of TOPEX/Poseidon, Jason-1, and ENVISAT satellite altimetry data. Model validation results showed that the satellitedriven water balance model can satisfactorily capture the patterns and seasonal variations of the Lake Turkana water level fluctuations with a Pearson's correlation coefficient of 0.90 and a Nash-Sutcliffe Coefficient of Efficiency (NSCE) of 0.80 during the validation period (2004-2009). Model error estimates were within 10% of the natural variability of the lake. Our analysis indicated that fluctuations in Lake Turkana water levels are mainly driven by lake inflows and over-the-lake evaporation. Over-the-lake rainfall contributes only up to 30% of lake evaporative demand. During the modelling time period, Lake Turkana showed seasonal variations of 1-2m. The lake level fluctuated in the range up to 4m between the years 1998-2009. This study demonstrated the usefulness of satellite altimetry data to calibrate and validate the satellite-driven hydrological model for Lake Turkana without using any in-situ data. Furthermore, for Lake Turkana, we identified and outlined opportunities and challenges of using a calibrated satellite-driven water balance

  11. Application and Evaluation of a Snowmelt Runoff Model in the Tamor River Basin, Eastern Himalaya Using a Markov Chain Monte Carlo (MCMC) Data Assimilation Approach

    NASA Technical Reports Server (NTRS)

    Panday, Prajjwal K.; Williams, Christopher A.; Frey, Karen E.; Brown, Molly E.

    2013-01-01

    Previous studies have drawn attention to substantial hydrological changes taking place in mountainous watersheds where hydrology is dominated by cryospheric processes. Modelling is an important tool for understanding these changes but is particularly challenging in mountainous terrain owing to scarcity of ground observations and uncertainty of model parameters across space and time. This study utilizes a Markov Chain Monte Carlo data assimilation approach to examine and evaluate the performance of a conceptual, degree-day snowmelt runoff model applied in the Tamor River basin in the eastern Nepalese Himalaya. The snowmelt runoff model is calibrated using daily streamflow from 2002 to 2006 with fairly high accuracy (average Nash-Sutcliffe metric approx. 0.84, annual volume bias <3%). The Markov Chain Monte Carlo approach constrains the parameters to which the model is most sensitive (e.g. lapse rate and recession coefficient) and maximizes model fit and performance. Model simulated streamflow using an interpolated precipitation data set decreases the fractional contribution from rainfall compared with simulations using observed station precipitation. The average snowmelt contribution to total runoff in the Tamor River basin for the 2002-2006 period is estimated to be 29.7+/-2.9% (which includes 4.2+/-0.9% from snowfall that promptly melts), whereas 70.3+/-2.6% is attributed to contributions from rainfall. On average, the elevation zone in the 4000-5500m range contributes the most to basin runoff, averaging 56.9+/-3.6% of all snowmelt input and 28.9+/-1.1% of all rainfall input to runoff. Model simulated streamflow using an interpolated precipitation data set decreases the fractional contribution from rainfall versus snowmelt compared with simulations using observed station precipitation. Model experiments indicate that the hydrograph itself does not constrain estimates of snowmelt versus rainfall contributions to total outflow but that this derives from the degree

  12. The biogenic approach to cognition.

    PubMed

    Lyon, Pamela

    2006-03-01

    After half a century of cognitive revolution we remain far from agreement about what cognition is and what cognition does. It was once thought that these questions could wait until the data were in. Today there is a mountain of data, but no way of making sense of it. The time for tackling the fundamental issues has arrived. The biogenic approach to cognition is introduced not as a solution but as a means of approaching the issues. The traditional, and still predominant, methodological stance in cognitive inquiry is what I call the anthropogenic approach: assume human cognition as the paradigm and work 'down' to a more general explanatory concept. The biogenic approach, on the other hand, starts with the facts of biology as the basis for theorizing and works 'up' to the human case by asking psychological questions as if they were biological questions. Biogenic explanations of cognition are currently clustered around two main frameworks for understanding biology: self-organizing complex systems and autopoiesis. The paper describes the frameworks and infers from them ten empirical principles--the biogenic 'family traits'--that constitute constraints on biogenic theorizing. Because the anthropogenic approach to cognition is not constrained empirically to the same degree, I argue that the biogenic approach is superior for approaching a general theory of cognition as a natural phenomenon. PMID:16628463

  13. Innovative approaches to recurrent training

    NASA Technical Reports Server (NTRS)

    Noon, H.; Murphy, M.

    1984-01-01

    Innovative approaches to recurrent training for regional airline aircrews are explored. Guidelines for recurrent training programs which include in corporation of cockpit resource management are discussed. B.W.

  14. The Middle Fossa Transpetrous Approach

    PubMed Central

    Nassif, Paul S.; Hankinson, Hal L.; Horn, Karl L.

    1997-01-01

    Surgical access to lesions of the temporal bone anterior to the internal auditory canal and medial to the petrous carotid artery has concerned surgeons for nearly a century. A variety of approaches have been developed to gain access to this region. We report our experience with the middle fossa transpetrous approach for the treatment of a variety of petroclival and/or prepontine lesions. Tentorial transection and the retrolabyrinthine approach to extend this technique is also discussed. In properly selected cases, the middle fossa transpetrous approach is successful in maintaining hearing, labyrinthine and facial function without compromising surgical exposure. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11 PMID:17171001

  15. Humane Education: A Curriculum Approach.

    ERIC Educational Resources Information Center

    Pearce, Robert W.

    1980-01-01

    Describes a curriculum-based approach to humane education and addresses the role of humane education in the school curriculum as well as the relationship's of education to other facets of animal welfare work. (Author/DS)

  16. Anterior Approach Total Hip Replacement

    MedlinePlus Videos and Cool Tools

    ... this view, I mean this is the traditional Smith Meet Jeu De view of the acetabulum,. I ... re using only part of what’s called the “Smith-Peterson approach.” The true Smith- Peterson, you would ...

  17. A Mathematical Approach to Hybridization

    ERIC Educational Resources Information Center

    Matthews, P. S. C.; Thompson, J. J.

    1975-01-01

    Presents an approach to hybridization which exploits the similarities between the algebra of wave functions and vectors. This method will account satisfactorily for the number of orbitals formed when applied to hybrids involving the s and p orbitals. (GS)

  18. Cancer and Complementary Health Approaches

    MedlinePlus

    ... practices of different groups of patients. What the Science Says About the Safety and Side Effects of ... whether or not it’s cancer-related. What the Science Says About the Effectiveness of Complementary Health Approaches ...

  19. Asteroid 433 Eros Approaches Earth

    NASA Video Gallery

    Asteroid 433 Eros made a close approach to Earth the morning of January 31st coming within 0.17 AU (15 million miles) of our planet. In this set of images taken that morning, the bright moving dot ...

  20. Paying for Complementary Health Approaches

    MedlinePlus

    ... use complementary health approaches, but the type of health insurance they have affects their decisions to use these ... more pronounced among those who did not have health insurance. For those who had health insurance, coverage for ...

  1. Approaches to Teaching Organizational Communication.

    ERIC Educational Resources Information Center

    Applebaum, Ronald L.

    1998-01-01

    Discusses fundamental problems in selecting an approach to organizational communications; the purpose of an organizational communication course; the structure and content of organizational communication coursework; and teaching strategies used in the basic course in organizational communication. (RS)

  2. New approaches to immunotoxicity testing.

    PubMed Central

    Archer, D L

    1982-01-01

    New approaches to immunotoxicity testing are reviewed and discussed. A method of activating T-cells in vivo is presented which circumvents artifacts dur to viability effects encountered with in vitro mitogen assays. The use of adoptive transfer approaches to combine the advantages of in vitro manipulation with in vivo function assays is discussed relative to natural killer cells. The need for an in vitro metabolic activation step coupled to other in vitro immunologic assays is discussed. PMID:7037382

  3. The Mesenteric Approach in Pancreatoduodenectomy.

    PubMed

    Nakao, Akimasa

    2016-01-01

    Isolated pancreatoduodenectomy (PD) is an ideal surgery for pancreatic head cancer. In cancer surgery, 'isolated' means en bloc resection using a non-touch isolation technique. I have been developing isolated PD for pancreatic cancer since 1981. In this operation, the most important and first step is to use a mesenteric approach instead of Kocher's maneuver. The precise surgical techniques of the mesenteric approach are introduced in this paper. PMID:27215213

  4. The information-processing approach.

    PubMed

    van der Heijden, A H; Stebbins, S

    1990-01-01

    The information-processing (IP) approach to perception and cognition arose as a reaction to behaviourism. This reaction mainly concerned the nature of explanation in scientific psychology. The "standard" account of behaviour, phrased in strictly external terms, was replaced by a "realist" account, phrased in terms of internal entities and processes. An analysis of the theoretical language used in IP psychology shows an undisciplined state of affairs. A great number of languages is simultaneously in use; no level of analysis is unambiguously referred to; and basic concepts such as information and processing remain largely undefined. Nevertheless, over the past 25 years the IP approach has developed into a disciplined and sophisticated experimental science. A look at actual practice hints at the basic reason for its success. The approach is not so much concerned with absolute or intrinsic properties of the human information processor, but with what can be called its relative or differential properties. A further analysis of this feature of the IP approach in terms of the formal language of a logical system makes explicit the basis of its success. The IP approach can be regarded as developing an empirical difference calculus on an unspecified class of objects, phrased in terms of a simulated "theory-neutral" observation language, and with operators that are structurally analogous to logical operators. This reinterpretation of what the IP approach is about brings a number of advantages. It strengthens its position as an independent science, clarifies its relation with other approaches within psychology and other sciences within the cognitive science group, and makes it independent of philosophical subtleties. PMID:2281128

  5. Using multi-approaches to investigate the effects of land cover on runoff and soil erosion in the Loess Plateau of China

    NASA Astrophysics Data System (ADS)

    Gao, G.; Fu, B.; Liu, Y.; Wang, Y.

    2012-12-01

    This study used the in-situ measurement, model simulation and radioisotope tracing methods to investigate the effects of land cover on runoff and soil erosion at plot and hillslope scales in the Loess Plateau of China. Three runoff plot groups covered by sparse young trees (Group 1), native shrubs (Group 2) and dense tussock (Group 3) with different revegetation time were established in the Yangjuangou catchment of Loess Plateau. Greater runoff was produced in plot groups (Group 2 and Group 3) with higher vegetation cover and longer restoration time as a result of soil compaction processes. Both of the runoff coefficient and soil loss rate decreased with increasing plot length in Group 2 and Group 3 plots. The runoff coefficient increased with plot length in Group 1 plots located at the early stage of revegetation, and the soil loss rates increased over an area threshold. Therefore, the effect of scale on runoff and soil erosion was dependent on restoration extent. The antecedent moisture condition (AMC) was explicitly incorporated in runoff production and initial abstraction of the SCS-CN model, and the direct effect of runoff on event soil loss was considered in the RUSLE model by adopting a rainfall-runoff erosivity factor. The modified SCS-CN and RUSLE models were coupled to link rainfall-runoff-erosion modeling. The modified SCS-CN model was accurate in predicting event runoff from the three plot groups with Nash-Sutcliffe model efficiency (EF) over 0.85, and the prediction accuracy of the modified RUSLE model was satisfactory with EF values being over 0.70. The 137Cs tracing technique was used to examine soil erosion under different land uses and land-use combinations. The results show that the order of erosion rate in different land uses increases sequentially from mature forest to grass to young forest to orchard to terrace crop. The land-use combinations of 'grass (6 years old) + mature forest (25 years old) + grass (25 years old)' and 'grass (6 years old

  6. Laparoscopic approach in gastrointestinal emergencies

    PubMed Central

    Jimenez Rodriguez, Rosa M; Segura-Sampedro, Juan José; Flores-Cortés, Mercedes; López-Bernal, Francisco; Martín, Cristobalina; Diaz, Verónica Pino; Ciuro, Felipe Pareja; Ruiz, Javier Padillo

    2016-01-01

    This review focuses on the laparoscopic approach to gastrointestinal emergencies and its more recent indications. Laparoscopic surgery has a specific place in elective procedures, but that does not apply in emergency situations. In specific emergencies, there is a huge range of indications and different techniques to apply, and not all of them are equally settle. We consider that the most controversial points in minimally invasive procedures are indications in emergency situations due to technical difficulties. Some pathologies, such as oesophageal emergencies, obstruction due to colon cancer, abdominal hernias or incarcerated postsurgical hernias, are nearly always resolved by conventional surgery, that is, an open approach due to limited intraabdominal cavity space or due to the vulnerability of the bowel. These technical problems have been solved in many diseases, such as for perforated peptic ulcer or acute appendectomy for which a laparoscopic approach has become a well-known and globally supported procedure. On the other hand, endoscopic procedures have acquired further indications, relegating surgical solutions to a second place; this happens in cholangitis or pancreatic abscess drainage. This endoluminal approach avoids the need for laparoscopic development in these diseases. Nevertheless, new instruments and new technologies could extend the laparoscopic approach to a broader array of potentials procedures. There remains, however, a long way to go. PMID:26973409

  7. Bayesian Approach for Inconsistent Information

    PubMed Central

    Stein, M.; Beer, M.; Kreinovich, V.

    2013-01-01

    In engineering situations, we usually have a large amount of prior knowledge that needs to be taken into account when processing data. Traditionally, the Bayesian approach is used to process data in the presence of prior knowledge. Sometimes, when we apply the traditional Bayesian techniques to engineering data, we get inconsistencies between the data and prior knowledge. These inconsistencies are usually caused by the fact that in the traditional approach, we assume that we know the exact sample values, that the prior distribution is exactly known, etc. In reality, the data is imprecise due to measurement errors, the prior knowledge is only approximately known, etc. So, a natural way to deal with the seemingly inconsistent information is to take this imprecision into account in the Bayesian approach – e.g., by using fuzzy techniques. In this paper, we describe several possible scenarios for fuzzifying the Bayesian approach. Particular attention is paid to the interaction between the estimated imprecise parameters. In this paper, to implement the corresponding fuzzy versions of the Bayesian formulas, we use straightforward computations of the related expression – which makes our computations reasonably time-consuming. Computations in the traditional (non-fuzzy) Bayesian approach are much faster – because they use algorithmically efficient reformulations of the Bayesian formulas. We expect that similar reformulations of the fuzzy Bayesian formulas will also drastically decrease the computation time and thus, enhance the practical use of the proposed methods. PMID:24089579

  8. Pigeons (Columba livia) associate time intervals with symbols in a touch screen task: evidence for ordinality but not summation.

    PubMed

    Olthof, Anneke; Santi, Angelo

    2007-02-01

    The present experiments examined whether pigeons can sum symbols that are associated with various temporal consequences in a touch screen apparatus. Pigeons were trained to discriminate between two visual symbols that were associated with 0, 1, 2, 3, 4, or 5 s either of delay to 4 s of hopper access (delay group) or duration of hopper access (reward group). In Experiment 1, the pigeons in both groups learned to select the symbol associated with the more favorable outcome, and they successfully transferred this discrimination to novel symbol pairs. However, when tested with 2 pairs of symbols associated with different summed durations, they responded on the basis of a simple response rule rather than the sum of the symbol pair. In Experiment 2, the reward group was presented with four symbols at once and was allowed to successively choose one symbol at a time. All pigeons chose the symbols in order from largest to smallest. This indicates that pigeons formed an ordered representation of symbols associated with different time intervals, even though they did not sum the symbols. PMID:17324078

  9. Evaluation of organochlorine compounds in peregrine falcon (Falco peregrinus) and their main prey (Columba livia) inhabiting central Spain.

    PubMed

    Merino, Rubén; Bordajandi, Luisa R; Abad, Esteban; Rivera, Josep; Jiménez, Begoña

    2005-08-01

    The population of peregrine falcon (Falco peregrinus sbs. brookei) inhabiting the Regional Park of southeastern Madrid (RPSM), Spain, has experienced an increase of unsuccessful pairs (from 15% among a total of 20 pairs in 1995 to 55% among a total of 18 pairs in 2001). Traditionally, this area has been known to be contaminated with organochlorine compounds and toxic metals, which are known to be deleterious to the reproductive system of birds. During the breeding seasons of 2000 and 2001, contaminant residues were measured in unhatched eggs of peregrine falcons and liver of their main prey, to determine if they could be affecting the survival of the population. The most abundant contaminants were ortho-polychlorinated biphenyls (ortho-PCBs), ranging from 202.56 to 3,335.16 ng/g (wet wt) in falcon eggs and from 10.25 to 53.51 ng/g (wet wt) in pigeon livers. In all samples, the 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were detected, although these levels never exceeded 20 pg/g (wet wt). The major contributor to total toxic equivalent quantities (TEQs) were non-ortho-PCBs. Organochlorine levels found in this study may contribute to the entire suite of stressors that are negatively affecting the peregrine population. PMID:16152983

  10. Effect of a commercial paratyphus vaccine on the development of pigeon circovirus infection in young pigeons (Columba livia domestica).

    PubMed

    Duchatel, Jean Pierre; Jauniaux, Thierry; Smyth, Joan; Habsch, Isabelle; de Bournonville, Marc; Losson, Bertrand; Todd, Danny

    2010-06-01

    Infection with pigeon circovirus (PiCV) has been associated with young pigeon disease syndrome (YPDS), which is considered to be a multifactorial disease. The factors that determine whether birds succumb to clinical disease are not known. To evaluate the potential effect of vaccination with a commercial paratyphus vaccine on the progression of PiCV infection in young pigeons, forty 6-week-old pigeons naturally infected with PiCV were randomly assigned to two equal groups. The pigeons of one group were vaccinated at 6 and 9 weeks of age, and pigeons of the second group were unvaccinated controls. Cloacal swab and blood samples collected from all the birds were tested for PiCV by polymerase chain reaction (PCR) analysis. Three weeks after the second vaccination, all pigeons were euthanatized, and tissues were collected for PiCV PCR analysis and histopathologic evaluation. No significant difference in the number of PCR-positive cloacal swab and blood samples was found between the vaccinated and control pigeons. Positive PCR results in tissue samples also were not significantly different between the groups, with 18 positive samples in vaccinated birds (90%) and 16 in control birds (80%). Characteristic botryoid inclusions were detected in more vaccinated than control pigeons, but this difference was not significant. In this study, vaccination with a commercial paratyphus vaccine was not a risk factor for development of young pigeon disease syndrome. PMID:20806655

  11. Vasoactive intestinal peptide binding sites and fibers in the brain of the pigeon Columba livia: An autoradiographic and immunohistochemical study

    SciTech Connect

    Hof, P.R.; Dietl, M.M.; Charnay, Y.; Martin, J.L.; Bouras, C.; Palacios, J.M.; Magistretti, P.J. )

    1991-03-15

    The distribution of vasoactive intestinal peptide (VIP) binding sites in the pigeon brain was examined by in vitro autoradiography on slide-mounted sections. A fully characterized monoiodinated form of VIP, which maintains the biological activity of the native peptide, was used throughout this study. The highest densities of binding sites were observed in the hyperstriatum dorsale, archistriatum, auditory field L of neostriatum, area corticoidea dorsolateralis and temporo-parieto-occipitalis, area parahippocampalis, tectum opticum, nucleus dorsomedialis anterior thalami, and in the periventricular area of the hypothalamus. Lower densities of specific binding occurred in the neostriatum, hyperstriatum ventrale and nucleus septi lateralis, dorsolateral area of the thalamus, and lateral and posteromedial hypothalamus. Very low to background levels of VIP binding were detected in the ectostriatum, paleostriatum primitivum, paleostriatum augmentatum, lobus parolfactorius, nucleus accumbens, most of the brainstem, and the cerebellum. The distribution of VIP-containing fibers and terminals was examined by indirect immunofluorescence using a polyclonal antibody against porcine VIP. Fibers and terminals were observed in the area corticoidea dorsolateralis, area parahippocampalis, hippocampus, hyperstriatum accessorium, hyperstriatum dorsale, archistriatum, tuberculum olfactorium, nuclei dorsolateralis and dorsomedialis of the thalamus, and throughout the hypothalamus and the median eminence. Long projecting fibers were visualized in the tractus septohippocampalis. In the brainstem VIP immunoreactive fibers and terminals were observed mainly in the substantia grisea centralis, fasciculus longitudinalis medialis, lemniscus lateralis, and in the area surrounding the nuclei of the 7th, 9th, and 10th cranial nerves.

  12. Detection of magnetic field intensity gradient by homing pigeons (Columba livia) in a novel "virtual magnetic map" conditioning paradigm.

    PubMed

    Mora, Cordula V; Bingman, Verner P

    2013-01-01

    It has long been thought that birds may use the Earth's magnetic field not only as a compass for direction finding, but that it could also provide spatial information for position determination analogous to a map during navigation. Since magnetic field intensity varies systematically with latitude and theoretically could also provide longitudinal information during position determination, birds using a magnetic map should be able to discriminate magnetic field intensity cues in the laboratory. Here we demonstrate a novel behavioural paradigm requiring homing pigeons to identify the direction of a magnetic field intensity gradient in a "virtual magnetic map" during a spatial conditioning task. Not only were the pigeons able to detect the direction of the intensity gradient, but they were even able to discriminate upward versus downward movement on the gradient by differentiating between increasing and decreasing intensity values. Furthermore, the pigeons typically spent more than half of the 15 second sampling period in front of the feeder associated with the rewarded gradient direction indicating that they required only several seconds to make the correct choice. Our results therefore demonstrate for the first time that pigeons not only can detect the presence and absence of magnetic anomalies, as previous studies had shown, but are even able to detect and respond to changes in magnetic field intensity alone, including the directionality of such changes, in the context of spatial orientation within an experimental arena. This opens up the possibility for systematic and detailed studies of how pigeons could use magnetic intensity cues during position determination as well as how intensity is perceived and where it is processed in the brain. PMID:24039812

  13. {delta}-ALAD activity variations in red blood cells in response to lead accumulation in rock doves (Columba livia)

    SciTech Connect

    Gonzalez, M.; Tejedor, M.C.

    1992-10-01

    The enzyme {delta}-aminolevulinic acid dehydratase ({delta}-ALAD, E.C. 4.2.1.24), catalyses the second step of the haeme biosynthetic pathway and is required to maintain the haemoglobin and cytochrome content in red cells. {delta}-ALAD is not only found in bone marrow cells, the major site of haeme synthesis, but also in circulating erythrocytes and other tissues. An inverse correlation was found between {delta}-ALAD activity in red blood cells and lead concentration in the blood. The degree of {delta}-ALAD inhibition in erythrocytes has been widely accepted as a standard bioassay to detect acute and chronic lead exposure in humans and in avians. The value of this parameter as an indicator for environmental lead has been often reported in doves and Scanlon. In lead-treated rats, an increase in {delta}-ALAD activity in bone marrow cells and in blood samples was shown by radioimmunoassay at 5 and 9 days after the treatment. Similarly, the amount of {delta}-ALAD seems to be more sensitive to lead in avian species than in mammals, the usefulness of blood {delta}-ALAD activity as an index of lead exposure has already been questioned by Hutton in the pigeon and by Jaffe et al. in humans. The present investigation studied the toxic effects of lead on rock dove red blood cell {delta}-ALAD activity in two situations: in doves treated with lead acetate in the laboratory and in doves exposed to the environment of Alcala de Henares. The final lead blood concentrations were lower in the environmental than in the laboratory doves. {delta}-ALAD activity in bone marrow cells and the relationships between lead accumulation and enzyme activity in red cells, are examined. 20 refs., 5 figs., 1 tab.

  14. Not just passengers: pigeons, Columba livia, can learn homing routes while flying with a more experienced conspecific

    PubMed Central

    Pettit, Benjamin; Flack, Andrea; Freeman, Robin; Guilford, Tim; Biro, Dora

    2013-01-01

    For animals that travel in groups, the directional choices of conspecifics are potentially a rich source of information for spatial learning. In this study, we investigate how the opportunity to follow a locally experienced demonstrator affects route learning by pigeons over repeated homing flights. This test of social influences on navigation takes advantage of the individually distinctive routes that pigeons establish when trained alone. We found that pigeons learn routes just as effectively while flying with a partner as control pigeons do while flying alone. However, rather than learning the exact route of the demonstrator, the paired routes shifted over repeated flights, which suggests that the birds with less local experience also took an active role in the navigational task. The efficiency of the original routes was a key factor in how far they shifted, with less efficient routes undergoing the greatest changes. In this context, inefficient routes are unlikely to be maintained through repeated rounds of social transmission, and instead more efficient routes are achieved because of the interaction between social learning and information pooling. PMID:23135677

  15. Functions of innate and acquired immune system are reduced in domestic pigeons (Columba livia domestica) given a low protein diet.

    PubMed

    Mabuchi, Yuko; Frankel, Theresa L

    2016-03-01

    Racing pigeons are exposed to and act as carriers of diseases. Dietary protein requirement for their maintenance has not been determined experimentally despite their being domesticated for over 7000 years. A maintenance nitrogen (protein) requirement (MNR) for pigeons was determined in a balance study using diets containing 6, 10 and 14% crude protein (CP). Then, the effects of feeding the diets were investigated to determine whether they were adequate to sustain innate and acquired immune functions. Nitrogen intake from the 6% CP diet was sufficient to maintain nitrogen balance and body weight in pigeons. However, the immune functions of phagocytosis, oxidative burst and lymphocyte proliferation in pigeons fed this diet were reduced compared with those fed 10 and 14% CP diets. Pigeons given the 6 and 10% CP diets had lower antibody titres following inoculation against Newcastle disease (ND) than those on the 14% CP diet. A confounding factor found on autopsy was the presence of intestinal parasites in some of the pigeons given the 6 and 10% CP diets; however, none of the pigeons used to measure MNR or acquired immunity to ND were infested with parasites. In conclusion, neither the 6 nor 10% CP diets adequately sustained acquired immune function of pigeons. PMID:27069640

  16. Temporal variation of the cestode, Cotugnia cuneata (Meggit, 1924) in their host, domestic pigeons, Columba livia domestica (Gmelin, 1789).

    PubMed

    Biswal, Debraj; Nandi, Anadi Prasad; Chatterjee, Soumendranath

    2015-06-01

    A study of the temporal variation of Cotugnia cuneata, on a monthly basis, was carried out from January 2008 to December 2010. The study revealed a similarity in the percentage prevalence and mean intensity of infection with higher values in the beginning of the year that gradually declined towards the middle and rose to moderate values towards the end of the year. The periodicity clearly shows a correlation with the seasonal changes throughout the year and provides important insights to the survival strategies of the parasite as well as its life-cycle. PMID:26063999

  17. Complete Genome Sequence of a Newcastle Disease Virus Isolated from a Rock Dove (Columba livia) in the Russian Federation.

    PubMed

    Yurchenko, Kseniya S; Sivay, Mariya V; Glushchenko, Alexandra V; Alkhovsky, Sergey V; Shchetinin, Alexey M; Shchelkanov, Michail Y; Shestopalov, Alexander M

    2015-01-01

    We report here the complete genome sequence of a Newcastle disease virus (NDV) isolate, NDV/Altai/pigeon/770/2011, isolated from a rock dove in the Russian Federation. On the basis of phylogenetic analysis, this strain was clustered into genotype VIb class II. PMID:25635008

  18. Conditioned suppression/avoidance as a procedure for testing hearing in birds: the domestic pigeon (Columba livia).

    PubMed

    Heffner, Henry E; Koay, Gimseong; Hill, Evan M; Heffner, Rickye S

    2013-06-01

    Although the domestic pigeon is commonly used in learning experiments, it is a notoriously difficult subject in auditory psychophysical experiments, even those in which it need only respond when it detects a sound. This is because pigeons tend to respond in the absence of sound-that is, they have a high false-positive rate-which makes it difficult to determine a pigeon's audiogram. However, false positives are easily controlled in the method of conditioned suppression/avoidance, in which a pigeon is trained to peck a key to obtain food and to stop pecking whenever it detects a sound that signals impending electric shock. Here, we describe how to determine psychophysical thresholds in pigeons using a method of conditioned suppression in which avoidable shock is delivered through a bead chain wrapped around the base of a pigeon's wings. The resulting audiogram spans the range from 2 to 8000 Hz; it falls approximately in the middle of the distribution of previous pigeon audiograms and supports the finding of Kreithen and Quine (Journal of Comparative Physiology 129:1-4, 1979) that pigeons hear infrasound. PMID:23055174

  19. Epidemiological survey of zoonotic pathogens in feral pigeons (Columba livia var. domestica) and sympatric zoo species in Southern Spain.

    PubMed

    Cano-Terriza, David; Guerra, Rafael; Lecollinet, Sylvie; Cerdà-Cuéllar, Marta; Cabezón, Oscar; Almería, Sonia; García-Bocanegra, Ignacio

    2015-12-01

    A cross-sectional study was carried out to determine the prevalence of pathogenic zoonotic agents (flaviviruses, avian influenza viruses (AIVs), Salmonella spp. and Toxoplasma gondii) in feral pigeons and sympatric zoo animals from Córdoba (Southern Spain) between 2013 and 2014. Antibodies against flaviviruses were detected in 7.8% out of 142 (CI95%: 3.7-11.8) pigeons, and 8.2% of 49 (CI95%: 0.9-15.4) of zoo animals tested. Antibodies with specificity against West Nile virus (WNV) and Usutu virus (USUV) were confirmed both in pigeons and in zoo birds. Even though seropositivity to AIVs was not detected in any of the analyzed pigeons, 17.9% of 28 (CI95%: 3.7-32.0) zoo birds tested showed positive results. Salmonella spp. was not isolated in any of 152 fecal samples collected from pigeons, while 6.8% of 44 zoo animals were positive. Antibodies against T. gondii were found in 9.2% of 142 (CI95%: 4.8-13.6) feral pigeons and 26.9% of 108 (CI95%: 19.6-34.1) zoo animals. This is the first study on flaviviruses and T. gondii in feral pigeons and captive zoo species in Spain. Antibodies against WNV and USUV detected in non-migratory pigeons and captive zoo animals indicate local circulation of these emerging pathogens in the study area. T. gondii was widespread in species analyzed. This finding could be of importance for Public Health and Conservation of endangered species present in zoo parks. Pigeons and zoo animals may be included as sentinel species for monitoring zoonotic pathogens in urban areas. PMID:26616657

  20. Changes in hippocampal volume and neuron number co-occur with memory decline in old homing pigeons (Columba livia).

    PubMed

    Coppola, Vincent J; Kanyok, Nate; Schreiber, Austin J; Flaim, Mary E; Bingman, Verner P

    2016-05-01

    The mammalian hippocampus is particularly susceptible to age-related structural changes, which have been used to explain, in part, age-related memory decline. These changes are generally characterized by atrophy (e.g., a decrease in volume and number of synaptic contacts). Recent studies have reported age-related spatial memory deficits in older pigeons similar to those seen in older mammals. However, to date, little is known about any co-occurring changes in the aging avian hippocampal formation (HF). In the current study, it was found that the HF of older pigeons was actually larger and contained more neurons than the HF of younger pigeons, a finding that suggests that the pattern of structural changes during aging in the avian HF is different from that seen in the mammalian hippocampus. A working hypothesis for relating the observed structural changes with spatial-cognitive decline is offered. PMID:27003117

  1. Morphometric characterisation of wing feathers of the barn owl Tyto alba pratincola and the pigeon Columba livia

    PubMed Central

    Bachmann, Thomas; Klän, Stephan; Baumgartner, Werner; Klaas, Michael; Schröder, Wolfgang; Wagner, Hermann

    2007-01-01

    Background Owls are known for their silent flight. Even though there is some information available on the mechanisms that lead to a reduction of noise emission, neither the morphological basis, nor the biological mechanisms of the owl's silent flight are known. Therefore, we have initiated a systematic analysis of wing morphology in both a specialist, the barn owl, and a generalist, the pigeon. This report presents a comparison between the feathers of the barn owl and the pigeon and emphasise the specific characteristics of the owl's feathers on macroscopic and microscopic level. An understanding of the features and mechanisms underlying this silent flight might eventually be employed for aerodynamic purposes and lead to a new wing design in modern aircrafts. Results A variety of different feathers (six remiges and six coverts), taken from several specimen in either species, were investigated. Quantitative analysis of digital images and scanning electron microscopy were used for a morphometric characterisation. Although both species have comparable body weights, barn owl feathers were in general larger than pigeon feathers. For both species, the depth and the area of the outer vanes of the remiges were typically smaller than those of the inner vanes. This difference was more pronounced in the barn owl than in the pigeon. Owl feathers also had lesser radiates, longer pennula, and were more translucent than pigeon feathers. The two species achieved smooth edges and regular surfaces of the vanes by different construction principles: while the angles of attachment to the rachis and the length of the barbs was nearly constant for the barn owl, these parameters varied in the pigeon. We also present a quantitative description of several characteristic features of barn owl feathers, e.g., the serrations at the leading edge of the wing, the fringes at the edges of each feather, and the velvet-like dorsal surface. Conclusion The quantitative description of the feathers and the specific structures of owl feathers can be used as a model for the construction of a biomimetic airplane wing or, in general, as a source for noise-reducing applications on any surfaces subjected to flow fields. PMID:18031576

  2. Functions of innate and acquired immune system are reduced in domestic pigeons (Columba livia domestica) given a low protein diet

    PubMed Central

    Mabuchi, Yuko; Frankel, Theresa L.

    2016-01-01

    Racing pigeons are exposed to and act as carriers of diseases. Dietary protein requirement for their maintenance has not been determined experimentally despite their being domesticated for over 7000 years. A maintenance nitrogen (protein) requirement (MNR) for pigeons was determined in a balance study using diets containing 6, 10 and 14% crude protein (CP). Then, the effects of feeding the diets were investigated to determine whether they were adequate to sustain innate and acquired immune functions. Nitrogen intake from the 6% CP diet was sufficient to maintain nitrogen balance and body weight in pigeons. However, the immune functions of phagocytosis, oxidative burst and lymphocyte proliferation in pigeons fed this diet were reduced compared with those fed 10 and 14% CP diets. Pigeons given the 6 and 10% CP diets had lower antibody titres following inoculation against Newcastle disease (ND) than those on the 14% CP diet. A confounding factor found on autopsy was the presence of intestinal parasites in some of the pigeons given the 6 and 10% CP diets; however, none of the pigeons used to measure MNR or acquired immunity to ND were infested with parasites. In conclusion, neither the 6 nor 10% CP diets adequately sustained acquired immune function of pigeons. PMID:27069640

  3. Understanding SARS with Wolfram approach.

    PubMed

    Li, Da-Wei; Pan, Yu-Xi; Duan, Yun; Hung, Zhen-De; Xu, Ming-Qing; He, Lin

    2004-01-01

    Stepping acquired immunodeficiency syndrome (AIDS), severe acute respiratory syndrome (SARS) as another type of disease has been threatening mankind since late last year. Many scientists worldwide are making great efforts to study the etiology of this disease with different approaches. 13 species of SARS virus have been sequenced. However, most people still largely rely on the traditional methods with some disadvantages. In this work, we used Wolfram approach to study the relationship among SARS viruses and between SARS viruses and other types of viruses, the effect of variations on the whole genome and the advantages in the analysis of SARS based on this novel approach. As a result, the similarities between SARS viruses and other coronaviruses are not really higher than those between SARS viruses and non-coronaviruses. PMID:14732867

  4. Anomaly Detection Using Behavioral Approaches

    NASA Astrophysics Data System (ADS)

    Benferhat, Salem; Tabia, Karim

    Behavioral approaches, which represent normal/abnormal activities, have been widely used during last years in intrusion detection and computer security. Nevertheless, most works showed that they are ineffective for detecting novel attacks involving new behaviors. In this paper, we first study this recurring problem due on one hand to inadequate handling of anomalous and unusual audit events and on other hand to insufficient decision rules which do not meet behavioral approach objectives. We then propose to enhance the standard decision rules in order to fit behavioral approach requirements and better detect novel attacks. Experimental studies carried out on real and simulated http traffic show that these enhanced decision rules improve detecting most novel attacks without triggering higher false alarm rates.

  5. Surgical approaches of endobronchial neoplasms

    PubMed Central

    Li, Zhigang; Kougioumtzi, Ioanna; Darwiche, Kaid; Tsakiridis, Kosmas; Katsikogiannis, Nikolaos; Stylianaki, Aikaterini; Kesisis, Georgios; Machairiotis, Nikolaos; Zarogoulidis, Konstantinos

    2013-01-01

    Endobronchial tumors are a rare entity that presents with different pathological findings. The interventional pulmonologist, but also the thoracic surgeon have at their disposal the same techniques for diagnosis, however; the two modalities differentiate in the treatment approach. Diagnosis evaluation should include lymph node evaluation. Minimal invasive techniques under local or general anesthesia are usually preferred by the interventional pulmonologists, whereas in the surgical approach of the thoracic surgeons the general anesthesia is necessary. A more extensive surgical approach either lobotomy or pneumonectomy should be performed in cases with positive intrapulmonary lymph nodes. Carinal reconstruction should be performed skillfully to get a negative proximal margin whenever needed. In the current manuscript we will present the methods of patient evaluation and surgical techniques for the management of these lesions. PMID:24102010

  6. A general approach to bosonization

    NASA Astrophysics Data System (ADS)

    Setlur, Girish S.; Meera, V.

    2007-10-01

    We summarize recent developments in the field of higher dimensional bosonization made by Setlur and collaborators and propose a general formula for the field operator in terms of currents and densities in one dimension using a new ingredient known as a `singular complex number'. Using this formalism, we compute the Green function of the homogeneous electron gas in one spatial dimension with short-range interaction leading to the Luttinger liquid and also with long-range interactions that lead to a Wigner crystal whose momentum distribution computed recently exhibits essential singularities. We generalize the formalism to finite temperature by combining with the author's hydrodynamic approach. The one-particle Green function of this system with essential singularities cannot be easily computed using the traditional approach to bosonization which involves the introduction of momentum cutoffs, hence the more general approach of the present formalism is proposed as a suitable alternative.

  7. Systems Science Approach to Data

    NASA Astrophysics Data System (ADS)

    Kadirkamanathan, Visakan

    Behaviours of many complex systems of interest cannot be adequately described since the underlying science has not advanced enough to be able to tease out the mathematical relationships. There is a need therefore to use methods and tools that capture the structure in the data that is representative of the systems behaviour. The subject of system identification allows us to deduce mathematical relations that govern the dynamics of systems based on the observed data. In addition, it can also be used to understand the system from basic principles. In this brief talk, the main approaches of systems science to data are reviewed identifying their strengths and limitations. The approaches include computational intelligence methods such as neural networks, genetic algorithms and fuzzy logic, as well as system identification methods in both time and frequency domains. Examples from physical science, neuroscience and social science serve to highlight achievements of the systems science approach to data.

  8. Employee Reactions to Merit Pay: Cognitive Approach and Social Approach

    ERIC Educational Resources Information Center

    Wang, Yingchun

    2010-01-01

    The dissertation aims to tackle one of the most pressing questions facing the merit pay system researchers and practitioners: Why do merit pay raises have such a small effect on employees' satisfaction, commitment and job performance? My approach to the study of this question is to develop explanatory frameworks from two perspectives: cognitive…

  9. Loss Modeling with a Data-Driven Approach in Event-Based Rainfall-Runoff Analysis

    NASA Astrophysics Data System (ADS)

    Chua, L. H. C.

    2012-04-01

    Mathematical models require the estimation of rainfall abstractions for accurate predictions of runoff. Although loss models such as the constant loss and exponential loss models are commonly used, these methods are based on simplified assumptions of the physical process. A new approach based on the data driven paradigm to estimate rainfall abstractions is proposed in this paper. The proposed data driven model, based on the artificial neural network (ANN) does not make any assumptions on the loss behavior. The estimated discharge from a physically-based model, obtained from the kinematic wave (KW) model assuming zero losses, was used as the only input to the ANN. The output is the measured discharge. Thus, the ANN functions as a black-box loss model. Two sets of data were analyzed for this study. The first dataset consists of rainfall and runoff data, measured from an artificial catchment (area = 25 m2) comprising two overland planes (slope = 11%), 25m long, transversely inclined towards a rectangular channel (slope = 2%) which conveyed the flow, recorded using calibrated weigh tanks, to the outlet. Two rain gauges, each placed 6.25 m from either ends of the channel, were used to record rainfall. Data for six storm events over the period between October 2002 and December 2002 were analyzed. The second dataset was obtained from the Upper Bukit Timah catchment (area = 6.4 km2) instrumented with two rain gauges and a flow measuring station. A total of six events recorded between November 1987 and July 1988 were selected for this study. The runoff predicted by the ANN was compared with the measured runoff. In addition, results from KW models developed for both the catchments were used as a benchmark. The KW models were calibrated assuming the loss rate for an average event for each of the datasets. The results from both the ANN and KW models agreed well with the runoff measured from the artificial catchment. The KW model is expected to perform well since the catchment

  10. A practical approach to TQI.

    PubMed

    Perras, S T; Mattern, M

    1994-04-01

    Total quality improvement (TQI) is a refreshing new approach to leadership that can be applied to a dialysis setting. The team approach to prospective data analysis is used for problem solution and reevaluation. Adapting theory to daily practical application can be successfully done using time, energy, and full senior management commitment. Staff education and involvement are essential to successful program implementation. Evaluation tools are easily adapted to analyze common dialysis problems. The initial time invested in education and data collection can be great but results in a streamlined process. PMID:8080313

  11. Probabilistic approach to EMP assessment

    SciTech Connect

    Bevensee, R.M.; Cabayan, H.S.; Deadrick, F.J.; Martin, L.C.; Mensing, R.W.

    1980-09-01

    The development of nuclear EMP hardness requirements must account for uncertainties in the environment, in interaction and coupling, and in the susceptibility of subsystems and components. Typical uncertainties of the last two kinds are briefly summarized, and an assessment methodology is outlined, based on a probabilistic approach that encompasses the basic concepts of reliability. It is suggested that statements of survivability be made compatible with system reliability. Validation of the approach taken for simple antenna/circuit systems is performed with experiments and calculations that involve a Transient Electromagnetic Range, numerical antenna modeling, separate device failure data, and a failure analysis computer program.

  12. Holistic approach to chronic constipation.

    PubMed

    Pescatori, Mario

    2006-01-01

    By "holistic approach" (greek "olos" = "all") we mean a clinical approach which is not only confined to the diseased segment of the body, say the inert large bowel or the spastic pelvic floor in case of constipation, but takes under consideration the whole "mind and body complex", which is a unique indivisible entity. According to a prospective study carried out in our Unit and under press in Colorectal Disease, 66% of the patients with obstructed defecation suffer either from anxiety or depression, thus showing the major role played by an altered psyche in the etiology of their constipation. PMID:17139889

  13. Systems biology approach to bioremediation

    SciTech Connect

    Chakraborty, Romy; Wu, Cindy H.; Hazen, Terry C.

    2012-06-01

    Bioremediation has historically been approached as a ‘black box’ in terms of our fundamental understanding. Thus it succeeds and fails, seldom without a complete understanding of why. Systems biology is an integrated research approach to study complex biological systems, by investigating interactions and networks at the molecular, cellular, community, and ecosystem level. The knowledge of these interactions within individual components is fundamental to understanding the dynamics of the ecosystem under investigation. Finally, understanding and modeling functional microbial community structure and stress responses in environments at all levels have tremendous implications for our fundamental understanding of hydrobiogeochemical processes and the potential for making bioremediation breakthroughs and illuminating the ‘black box’.

  14. Synergistic approach to patient dialysate

    PubMed Central

    Dragotoiu, A; Checheriţă, AI; Ciocâlteu, A; Rizeanu, S

    2015-01-01

    The stress a patient is subjected to during dialysis treatment can be reduced by using a synergetic approach by the medical team. The integration into therapy of the positive psychical resources such as: active positive coping mechanisms, individual or family mental resilience, improvement of the image and self-esteem, better tolerance to frustration can represent an important part in the improvement of the patient’s quality of life, determination of a positive approach of the situations both for him and close friends and relatives. PMID:26361514

  15. Support for Quitting: Choose Your Approach

    MedlinePlus

    ... Choose your approach Self-help strategies for quiting Social support Professional help Tools Calculators Cocktail content calculator Drink ... your approach Self-help strategies for quitting drinking Social support to stop drinking Professional help Choose your approach ...

  16. Potential for dietary ω-3 fatty acids to prevent nonalcoholic fatty liver disease and reduce the risk of primary liver cancer.

    PubMed

    Jump, Donald B; Depner, Christopher M; Tripathy, Sasmita; Lytle, Kelli A

    2015-11-01

    Nonalcoholic fatty liver disease (NAFLD) has increased in parallel with central obesity, and its prevalence is anticipated to increase as the obesity epidemic remains unabated. NAFLD is now the most common cause of chronic liver disease in developed countries and is defined as excessive lipid accumulation in the liver, that is, hepatosteatosis. NAFLD ranges in severity from benign fatty liver to nonalcoholic steatohepatitis (NASH), and NASH is characterized by hepatic injury, inflammation, oxidative stress, and fibrosis. NASH can progress to cirrhosis, and cirrhosis is a risk factor for primary hepatocellular carcinoma (HCC). The prevention of NASH will lower the risk of cirrhosis and NASH-associated HCC. Our studies have focused on NASH prevention. We developed a model of NASH by using mice with the LDL cholesterol receptor gene ablated fed the Western diet (WD). The WD induces a NASH phenotype in these mice that is similar to that seen in humans and includes robust induction of hepatic steatosis, inflammation, oxidative stress, and fibrosis. With the use of transcriptomic, lipidomic, and metabolomic approaches, we examined the capacity of 2 dietary ω-3 (n-3) polyunsaturated fatty acids, eicosapentaenoic acid (20:5ω-3; EPA) and docosahexaenoic acid (22:6ω-3; DHA), to prevent WD-induced NASH. Dietary DHA was superior to EPA at attenuating WD-induced changes in plasma lipids and hepatic injury and at reversing WD effects on hepatic metabolism, oxidative stress, and fibrosis. The outcome of these studies suggests that DHA may be useful in preventing NASH and reducing the risk of HCC. PMID:26567194

  17. Approaching Bose-Einstein Condensation

    ERIC Educational Resources Information Center

    Ferrari, Loris

    2011-01-01

    Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial…

  18. Building America Systems Engineering Approach

    SciTech Connect

    2011-12-15

    The Building America Research Teams use a systems engineering approach to achieve higher quality and energy savings in homes. Using these techniques, the energy consumption of new houses can be reduced by 40% or more with little or no impact on the cost of ownership.

  19. Novel Approaches to Surfactant Administration

    PubMed Central

    Gupta, Samir; Donn, Steven M.

    2012-01-01

    Surfactant replacement therapy has been the mainstay of treatment for preterm infants with respiratory distress syndrome for more than twenty years. For the most part, surfactant is administered intratracheally, followed by mechanical ventilation. In recent years, the growing interest in noninvasive ventilation has led to novel approaches of administration. This paper will review these techniques and the associated clinical evidence. PMID:23243504

  20. Thoracoscopy: a collaborative surgical approach.

    PubMed

    Brand, A F

    1995-07-01

    Perioperative nurses, surgeons, anesthesiologists, certified registered nurse anesthetists, and pharmacists are meeting the challenge of decreasing thoracic surgical patients' length of hospital stay with thoracoscopy. This innovative alternative to traditional thoracotomy procedures has been achieved through an attentive team approach using the fundamental perioperative skills of assessment, positioning, safety, and sharing of knowledge. PMID:7647761

  1. Clinical Approach to Teacher Evaluation.

    ERIC Educational Resources Information Center

    Tipton, William

    This manual, prepared for the state of Washington, provides tools and strategies aimed at assisting building administrators in clinical approaches to teacher evaluation. The first section provides preliminary thoughts on the evaluation process and discusses the two major problems: acceptance and time. The second section discusses the sources and…

  2. Multimethod Approaches in Educational Research

    ERIC Educational Resources Information Center

    Elliott, Julian

    2004-01-01

    Noting the attractions of self-report questionnaires and surveys to those engaged in educational research, this article discusses some of the problems that can arise from their injudicious use. It is argued that the potentially misleading nature of findings from such approaches is particularly highlighted when mixed methodologies are employed.…

  3. The Labelling Approach to Deviance.

    ERIC Educational Resources Information Center

    Rains, Prudence M.; Kitsuse, John L.; Duster, Troy; Freidson, Eliot

    2003-01-01

    This reprint of one chapter from the 1975 text, "Issues in the Classification of Children" by Nicholas Hobbs and others, addresses the theoretical, methodological, and empirical issues involved in the "labeling" approach to the sociology of deviance. It examines the social process of classification, the use of classification in social agencies,…

  4. Budgeting Approaches in Community Colleges

    ERIC Educational Resources Information Center

    Palmer, James C.

    2014-01-01

    Several budgeting approaches have been initiated as alternatives to the traditional, incremental process. These include formula budgeting; zero-base budgeting; planning, programming, and budgeting systems; and responsibility center budgeting. Each is premised on assumptions about how organizations might best make resource allocation decisions.…

  5. Early Writing: A Developmental Approach.

    ERIC Educational Resources Information Center

    Goetz, Elizabeth; And Others

    This document consists of four papers on the acquisition of writing skills by young children. The first paper provides a historical and developmental perspective on early writing. Children's development of manual dexterity is briefly overviewed and aspects of the educational approaches of Pestalozzi, Montessori, Chomsky, Rogers and Ashton-Warner…

  6. A Different Approach Pays Off.

    ERIC Educational Resources Information Center

    Sisk, Dorothy

    1993-01-01

    Project Step-Up (Systematic Training of Educational Programs for Underserved Pupils) locates children from minority, economically disadvantaged populations with high potential in Texas, Arkansas, Florida, and Arizona and then uses a teaching approach that emphasizes critical thinking, vocabulary building, self-esteem strengthening, problem…

  7. Animal timing: a synthetic approach.

    PubMed

    de Carvalho, Marilia Pinheiro; Machado, Armando; Vasconcelos, Marco

    2016-07-01

    Inspired by Spence's seminal work on transposition, we propose a synthetic approach to understanding the temporal control of operant behavior. The approach takes as primitives the temporal generalization gradients obtained in prototypical concurrent and retrospective timing tasks and then combines them to synthetize more complex temporal performances. The approach is instantiated by the learning-to-time (LeT) model. The article is divided into three parts. In the first part, we review the basic findings concerning the generalization gradients observed in fixed-interval schedules, the peak procedure, and the temporal generalization procedure and then describe how LeT explains them. In the second part, we use LeT to derive by gradient combination the typical performances observed in mixed fixed-interval schedules, the free-operant psychophysical procedure, the temporal bisection task, and the double temporal bisection task. We also show how the model plays the role of a useful null hypothesis to examine whether temporal control in the bisection task is relative or absolute. In the third part, we identify a set of issues that must be solved to advance our understanding of temporal control, including the shape of the generalization gradients outside the range of trained stimulus durations, the nature of temporal memories, the influence of context on temporal learning, whether temporal control can be inhibitory, and whether temporal control is also relational. These issues attest to the heuristic value of a Spencean approach to temporal control. PMID:27000781

  8. [Mixed approaches in nursing science].

    PubMed

    Dupin, Cécile-Marie

    2015-06-01

    Mixed methods research uses methodologies from quantitative and qualitative approaches in a single project. Thanks to the integration of the results of the studies, complex phenomena can be explored. The designs are based on specific criteria of rigour. Strategies exist for the design of this type of research. PMID:26146330

  9. Map Projections: Approaches and Themes

    ERIC Educational Resources Information Center

    Steward, H. J.

    1970-01-01

    Map projections take on new meaning with location systems needed for satellites, other planets and space. A classroom approach deals first with the relationship between the earth and the globe, then with transformations to flat maps. Problems of preserving geometric qualities: distance, angles, directions are dealt with in some detail as are…

  10. General Education: An Interdisciplinary Approach.

    ERIC Educational Resources Information Center

    Scott, Charles V.; Moore, Kenneth D.

    The University of Science and Arts of Oklahoma, an experimental college, has developed an innovative general education program. Teaching approaches and organizational structures of the program have been changed to accommodate the new curriculum. The general education core, called the Interdisciplinary Studies Sequence (IDS), includes courses in…

  11. A SYSTEM APPROACH FOR EDUCATION.

    ERIC Educational Resources Information Center

    STEWART, DONALD

    TECHNIQUES IN EDUCATION MUST BE DEVELOPED WHICH ARE IN KEEPING WITH TECHNOLOGICAL ADVANCE. A DOCTRINE OF "CONCURRENCY" IS NECESSARY SO THAT EDUCATION WILL COINCIDE WITH NEW DEVELOPMENTS IN SOCIETY. A SYSTEM APPROACH IN EDUCATION CAN DO THIS BY PROVIDING A CONCEPTUAL FRAMEWORK FOR PLANNING, ORDERLY CONSIDERATION OF FUNCTIONS AND RESOURCES, AND A…

  12. LANGUAGE TEACHING, A SCIENTIFIC APPROACH.

    ERIC Educational Resources Information Center

    LADO, ROBERT

    DESIGNED TO UPDATE THE CONTEMPORARY LANGUAGE TEACHER'S KNOWLEDGE OF THE INNOVATIONS IN HIS FIELD, THIS BOOK INTRODUCES SOME OF THE ESSENTIAL MAJOR AREAS OF WHICH HE SHOULD HAVE AN UNDERSTANDING TO APPROACH HIS WORK SCIENTIFICALLY. PART ONE, DEALING IN GENERAL TERMS WITH LANGUAGE AND LANGUAGE LEARNING, SETS THE TONE OF THE BOOK WITH DISCUSSIONS OF…

  13. Comparative Psychology: An Epigenetic Approach.

    ERIC Educational Resources Information Center

    Greenberg, Gary

    1987-01-01

    A comparative psychology course oriented around the themes of phylogeny and ontogeny is described. The course emphasizes the evolution and development of behavioral processes and includes a discussion of the concept of integrative levels and Schneirla's approach/withdrawal theory. The course evaluates genetic determinism and stresses the principle…

  14. Kibbutz Education: An Historical Approach.

    ERIC Educational Resources Information Center

    Near, Henry

    1982-01-01

    An historical approach to Israeli education in the kibbutz focuses on communal educational practices stemming from the ideological influences of the kibbutz youth movement. Work is an essential part of the kibbutz educational process and is integrated with the total life of the kibbutz. (JN)

  15. Toxicological approaches to complex mixtures.

    PubMed Central

    Mauderly, J L

    1993-01-01

    This paper reviews the role of toxicological studies in understanding the health effects of environmental exposures to mixtures. The approach taken is to review mixtures that have received the greatest emphasis from toxicology; major mixtures research programs; the toxicologist's view of mixtures and approaches to their study; and the complementary roles of toxicological, clinical, and epidemiological studies. Studies of tobacco smoke, engine exhaust, combustion products, and air pollutants comprise most of the past research on mixtures. Because of their great experimental control over subjects, exposures, and endpoints, toxicologists tend to consider a wider range of toxic interactions among mixture components and sequential exposures than is practical for human studies. The three fundamental experimental approaches used by toxicologists are integrative (studying the mixture as a whole), dissective (dissecting a mixture to determine causative constituents), and synthetic (studying interactions between agents in simple combinations). Toxicology provides information on potential hazards, mechanisms by which mixture constituents interact to cause effects, and exposure dose-effect relationships; but extrapolation from laboratory data to quantitative human health risks is problematic. Toxicological, clinical, and epidemiological approaches are complementary but are seldom coordinated. Fostering synergistic interactions among the disciplines in studying the risks from mixtures could be advantageous. PMID:7515806

  16. Partnership in Sector Wide Approaches

    ERIC Educational Resources Information Center

    Tolley, Hilary

    2011-01-01

    Within the context of bilateral support to the education sector in Tonga and the Solomon Islands, this paper will explore how the discourse of "partnership" has been interpreted and activated within the Sector wide approach (SWAp). In concentrating particularly on the relationship between the respective Ministries of Education and New Zealand's…

  17. Technical Training: A Systematic Approach.

    ERIC Educational Resources Information Center

    Gammuto, John J.

    1980-01-01

    To employ scarce personnel and money to best advantage, company management must diagnose critical training needs and assign them priorities. A systems approach is recommended, which gives focus to training design while accommodating most organization training goals. Included are suggestions for system design, facility management, and cost…

  18. The Power Approach to Writing.

    ERIC Educational Resources Information Center

    Witt, Elaine B.

    This course of study presents a competency-based approach to teaching effective writing. It is intended to give the adult educator a tool that can be used for any level of student at any point in writing instruction. The first section contains 48 competencies that address 5 domains of writing--planning, organizing, writing, evaluating, and…

  19. New Approaches to Comparative Education.

    ERIC Educational Resources Information Center

    Altbach, Philip G., Ed.; Kelly, Gail P., Ed.

    Perspectives on research in comparative education are presented in 17 articles originally published in the "Comparative Education Review." The objective is to present an array of new viewpoints, orientations, and approaches. Titles and authors are: "Introduction: Perspectives on Comparative Education" (Philip G. Altbach, Gail P. Kelly); "Critical…

  20. Ethnic Studies: Issues and Approaches.

    ERIC Educational Resources Information Center

    Yang, Philip Q.

    This book offers a comprehensive definition of the field of ethnic studies, covering both major issues in the field and its theoretical and methodological approaches. It traces the origins and evolution of the discipline in the United States and maps its domain. Some of the current issues addressed include affirmative action, illegal/legal…

  1. Twenty Approaches to Individual Change

    ERIC Educational Resources Information Center

    Ewing, Dorlesa Barmettler

    1977-01-01

    The author reviews traditional helping systems of therapy, i.e., psychonalytic, experiential/phenomenological, cognitive, and behavioral, as well as mind-body systems approaches of transcendental meditation, biofeedback, aerobic exercise training, nutrition, and bioenergetics analysis. Therapists are admonished to learn about these various…

  2. Approaches to Academic Growth Assessment

    ERIC Educational Resources Information Center

    Anderman, Eric M.; Gimbert, Belinda; O'Connell, Ann A.; Riegel, Lisa

    2015-01-01

    Background: There is much interest in assessing growth in student learning. Assessments of growth have important implications and affect many policy decisions at many levels. Aims: In the present article, we review some of the different approaches to measuring growth and examine the implications of their usage. Sample: Samples used in research on…

  3. Guitar Class: A Multifaceted Approach.

    ERIC Educational Resources Information Center

    Bartel, Lee R.

    1990-01-01

    Suggests that the bias linking guitars to popular culture has needlessly limited approaches to teaching guitar. Examines how each of five current programs develops different music skills. Advocates a comprehensive, multifaceted program capable of emphasizing student skills in melody, harmony, perception, creativity, and performance over six years…

  4. Approach to Pediatric Chest Radiograph.

    PubMed

    Jana, Manisha; Bhalla, Ashu Seith; Gupta, Arun Kumar

    2016-06-01

    Chest radiograph remains the first line imaging modality even today, especially in ICU settings. Hence proper interpretation of chest radiographs is crucial, which can be achieved by adopting a systematic approach and proper description and identification of abnormalities. In this review, the authors describe a short and comprehensive way of interpreting the pediatric chest radiograph. PMID:26983619

  5. ENGLISH WRITING, APPROACHES TO COMPOSITION.

    ERIC Educational Resources Information Center

    Euclid English Demonstration Center, OH.

    THIS COLLECTION OF PAPERS BY STAFF MEMBERS OF THE EUCLID ENGLISH DEMONSTRATION CENTER FOCUSES ON APPROACHES TO THE TEACHING OF COMPOSITION IN THE JUNIOR HIGH SCHOOL. THE PAPERS ARE (1) "LITERATURE AND COMPOSITION," BY JAMES F. MCCAMPBELL, (2) "COMPOSING--EPIPHANY AND DETAIL," BY JOSEPH DYESS, (3) "THE LANGUAGE COMPOSITION ACT," BY LESTER E.…

  6. Chemical Calculations; An Audiotutorial Approach.

    ERIC Educational Resources Information Center

    Lower, Stephen K.

    An audiotutorial approach to problem-solving in college chemistry relying upon audio tapes is available. The program is designed to increase the teacher's effectiveness by providing individualized attention to student difficulties related to problem-solving. Problem solutions are recorded on audio tapes (designed for use with Sony TC-160 cassettes…

  7. Overcoming Prejudices: An Invitational Approach.

    ERIC Educational Resources Information Center

    Reed, Charlotte

    1996-01-01

    Offers an invitational model for overcoming prejudices. The model, based on the five-step approach of M. Haberman (1994) and the conflict management plan of W. W. Purkey (1992) proposes an effective and sensitive method for dealing with prejudice and discrimination in the schools. (SLD)

  8. A Psychoanalytic Approach to Fieldwork

    ERIC Educational Resources Information Center

    Ramvi, Ellen

    2012-01-01

    This article focuses on what both psychoanalysis and anthropology have in common: the emphasis on the researcher's own experience. An ethnographic fieldwork will be used to illustrate how a psychoanalytical approach unfolds the material when studying conditions for learning from experience among teachers in two Norwegian junior high schools, and…

  9. Teacher Training: A Personal Approach.

    ERIC Educational Resources Information Center

    Henson, Kenneth T.

    Indiana State University has developed an experimental program to develop a personal approach to teacher training. The ultimate intention of the program is to produce educators who are personally committed to the development of the young people often collectively labeled "students." Devices used in the program include the use of student names,…

  10. An Approach for Dynamic Grids

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Liou, Meng-Sing; Hindman, Richard G.

    1994-01-01

    An approach is presented for the generation of two-dimensional, structured, dynamic grids. The grid motion may be due to the motion of the boundaries of the computational domain or to the adaptation of the grid to the transient, physical solution. A time-dependent grid is computed through the time integration of the grid speeds which are computed from a system of grid speed equations. The grid speed equations are derived from the time-differentiation of the grid equations so as to ensure that the dynamic grid maintains the desired qualities of the static grid. The grid equations are the Euler-Lagrange equations derived from a variational statement for the grid. The dynamic grid method is demonstrated for a model problem involving boundary motion, an inviscid flow in a converging-diverging nozzle during startup, and a viscous flow over a flat plate with an impinging shock wave. It is shown that the approach is more accurate for transient flows than an approach in which the grid speeds are computed using a finite difference with respect to time of the grid. However, the approach requires significantly more computational effort.

  11. A synthetic approach to abiogenesis.

    PubMed

    Attwater, James; Holliger, Philipp

    2014-05-01

    Synthetic biology seeks to probe fundamental aspects of biological form and function by construction (resynthesis) rather than deconstruction (analysis). Here we discuss how such an approach could be applied to assemble synthetic quasibiological systems able to replicate and evolve, illuminating universal properties of life and the search for its origins. PMID:24781322

  12. Open Universities: A Comparative Approach.

    ERIC Educational Resources Information Center

    Kaye, Tony; Rumble, Greville

    1991-01-01

    Attempts to draw comparisons between the different ways that distance education methods have been used for postsecondary education. Emphasizes the differences in scale, curricula, teaching approaches, and resource levels at different institutions in different nations. Explores problems such as lack of discussion, inflexibility, high cost of…

  13. Interdisciplinary Approach to Building Construction.

    ERIC Educational Resources Information Center

    Armstrong, Harry

    The paper discusses the interdisciplinary approach used by the Amity High School House Construction Project to develop a construction cluster in a small high school, to give students on-the-job training, and to teach them the relevancy of academic education. The project's monthly plan of action is briefly described. Suggested activities,…

  14. A Freudian Approach to Education.

    ERIC Educational Resources Information Center

    Gartner, Sandra L.

    This document offers the point of view that Bruno Bettelheim's writings, based on Sigmund Freud's approach to education, suggest the most practical applications for achieving positive results within the classroom. The overall result of a student being taught all through school by the Freudian method would be an extremely positive one. Such a…

  15. Transfer Articulation: A Team Approach.

    ERIC Educational Resources Information Center

    Weinman, Elaine; Dutka, Julia To

    1993-01-01

    In response to problems of transfer students from two-year colleges, Montclair State College (New Jersey) has developed an articulation model based on a program-to-program approach. The system specifically addresses issues of course content, program goals, and curricular expectations. It coordinates contributions from all segments of the college…

  16. Teaching Persuasion: A Positive Approach.

    ERIC Educational Resources Information Center

    Fenton, Mary C.

    The synthesis of four instructional models for argumentative writing--the Toulmin, Hiduke, Winder, and Crebbe-Debate approaches--with basic discourse theory produces a practical and positive method of teaching college students to write effective persuasive essays. A battery of questions based on a modified communication triangle--subject…

  17. Negotiations: Try a Pragmatic Approach.

    ERIC Educational Resources Information Center

    Prenn, Kathryn J.; Coughlin, John T.

    1986-01-01

    With adequate preparation, effort, and commitment, the school system's collective bargaining process can become an opportunity for management and employee organizations to resolve significant concerns. This paper recommends nine steps for a pragmatic approach to negotiations. (1) Prepare: Preparation includes reviewing the current collective…

  18. Multidisciplinary Approaches in Evolutionary Linguistics

    ERIC Educational Resources Information Center

    Gong, Tao; Shuai, Lan; Wu, Yicheng

    2013-01-01

    Studying language evolution has become resurgent in modern scientific research. In this revival field, approaches from a number of disciplines other than linguistics, including (paleo)anthropology and archaeology, animal behaviors, genetics, neuroscience, computer simulation, and psychological experimentation, have been adopted, and a wide scope…

  19. Interdisciplinary Approaches to Science Education.

    ERIC Educational Resources Information Center

    McGinnis, Jane

    This paper addresses the problem of an inadequate science teaching approach at a time when students need to be familiar with, and be able to understand, global problems and personal problems delving into complex, interrelated issues based on the science of a living universe. This report focuses on research about the problems in science education,…

  20. Innovative Approaches to Career Guidance.

    ERIC Educational Resources Information Center

    Freeman, Andrew R.

    A key part of a broad-based approach to career education in Australian schools is vocational/career guidance. Various vocational guidance programs have been developed for specific groups in Australian society, including work experience, caravans, and micrographics technology for the handicapped; pre-employment courses and a family education center…

  1. Cleft Palate; A Multidiscipline Approach.

    ERIC Educational Resources Information Center

    Stark, Richard B., Ed.

    Nineteen articles present a multidisciplinary approach to the management of facial clefts. The following subjects are discussed: the history of cleft lip and cleft palate surgery; cogenital defects; classification; the operation of a cleft palate clinic; physical examination of newborns with cleft lip and/or palate; nursing care; anesthesia;…

  2. Approaches to Drug Abuse Prevention

    ERIC Educational Resources Information Center

    Gordon, Paula D.

    1971-01-01

    This article concerns the drug abuse related definitions of the words education" and prevention" as they have come to be used today. The writer infers that the changing uses of these words reflects an increasingly more enlightened approach to ameliorating the problem of drug abuse. (Author)

  3. Approaches to Drug Abuse Counseling.

    ERIC Educational Resources Information Center

    Boren, John J., Ed.; Onken, Lisa Simon, Ed.; Carroll, Kathleen M., Ed.

    The intent of this book is to present information on various counseling approaches for drug abuse used in some of the best known and most respected treatment programs in the United States. In an effort to make the comparison of the various models less difficult and to clarify how the model is applied in practice, each chapter follows a specific…

  4. Minimalist Approach to Perceptual Interactions

    PubMed Central

    Lenay, Charles; Stewart, John

    2012-01-01

    Work aimed at studying social cognition in an interactionist perspective often encounters substantial theoretical and methodological difficulties: identifying the significant behavioral variables; recording them without disturbing the interaction; and distinguishing between: (a) the necessary and sufficient contributions of each individual partner for a collective dynamics to emerge; (b) features which derive from this collective dynamics and escape from the control of the individual partners; and (c) the phenomena arising from this collective dynamics which are subsequently appropriated and used by the partners. We propose a minimalist experimental paradigm as a basis for this conceptual discussion: by reducing the sensory inputs to a strict minimum, we force a spatial and temporal deployment of the perceptual activities, which makes it possible to obtain a complete recording and control of the dynamics of interaction. After presenting the principles of this minimalist approach to perception, we describe a series of experiments on two major questions in social cognition: recognizing the presence of another intentional subject; and phenomena of imitation. In both cases, we propose explanatory schema which render an interactionist approach to social cognition clear and explicit. Starting from our earlier work on perceptual crossing we present a new experiment on the mechanisms of reciprocal recognition of the perceptual intentionality of the other subject: the emergent collective dynamics of the perceptual crossing can be appropriated by each subject. We then present an experimental study of opaque imitation (when the subjects cannot see what they themselves are doing). This study makes it possible to characterize what a properly interactionist approach to imitation might be. In conclusion, we draw on these results, to show how an interactionist approach can contribute to a fully social approach to social cognition. PMID:22582041

  5. Minimalist approach to perceptual interactions.

    PubMed

    Lenay, Charles; Stewart, John

    2012-01-01

    WORK AIMED AT STUDYING SOCIAL COGNITION IN AN INTERACTIONIST PERSPECTIVE OFTEN ENCOUNTERS SUBSTANTIAL THEORETICAL AND METHODOLOGICAL DIFFICULTIES: identifying the significant behavioral variables; recording them without disturbing the interaction; and distinguishing between: (a) the necessary and sufficient contributions of each individual partner for a collective dynamics to emerge; (b) features which derive from this collective dynamics and escape from the control of the individual partners; and (c) the phenomena arising from this collective dynamics which are subsequently appropriated and used by the partners. We propose a minimalist experimental paradigm as a basis for this conceptual discussion: by reducing the sensory inputs to a strict minimum, we force a spatial and temporal deployment of the perceptual activities, which makes it possible to obtain a complete recording and control of the dynamics of interaction. After presenting the principles of this minimalist approach to perception, we describe a series of experiments on two major questions in social cognition: recognizing the presence of another intentional subject; and phenomena of imitation. In both cases, we propose explanatory schema which render an interactionist approach to social cognition clear and explicit. Starting from our earlier work on perceptual crossing we present a new experiment on the mechanisms of reciprocal recognition of the perceptual intentionality of the other subject: the emergent collective dynamics of the perceptual crossing can be appropriated by each subject. We then present an experimental study of opaque imitation (when the subjects cannot see what they themselves are doing). This study makes it possible to characterize what a properly interactionist approach to imitation might be. In conclusion, we draw on these results, to show how an interactionist approach can contribute to a fully social approach to social cognition. PMID:22582041

  6. A Hybrid Regional Approach to Model Discharge at Multiple Sub-Basins within the Calapooia Watershed, Oregon, USA

    NASA Astrophysics Data System (ADS)

    Leibowitz, S. G.; Wigington, P. J.; Patil, S.; Comeleo, R. L.

    2012-12-01

    point discharge measurements over a 2-3 year period found log transformed Nash-Sutcliffe efficiencies (NSE) ranging from 0.23 to 0.97 and averaging 0.73. NSE values were greater than 0.6 for all but two of the sub-basins. The ability of the combined lowland and mountain models to estimate discharge in the different sub-basins supports our hypothesis that sub-basin hydrology in the Calapooia is dominated by broad, regional factors (lowland vs. mountain terrain) rather than local (sub-basin) characteristics. Future work will combine this hybrid model with an approach for estimating intermittent and ephemeral flows to assess the ecosystem services of different stream types. The model will also be combined with nitrogen and fish models to further investigate ecosystem services in the Calapooia basin.

  7. Connectionist approach to adaptive reasoning

    NASA Astrophysics Data System (ADS)

    Reddy, Mohan S.; Pandya, Abhijit S.; Reddy, D. V.

    1995-06-01

    This paper illustrates the neural net approach to constructing a fuzzy logic decision system. This technique employs an artificial neural network (ANN) to recognize the relationships that exist between the various inputs and outputs. An ANN is constructed based on the variable present in the application. The network is trained and tested. After successful testing, the ANN is exposed to new data and the results are grouped into fuzzy membership sets. This data grouping forms the basis of a new ANN. The network is now trained and tested with the fuzzy membership data. New data is presented to the trained network and the results from the fuzzy implications. This approach is used to compute skid resistance values from G-analyst accelerometer readings on open grid bridge decks.

  8. BIOLOGICAL APPROACHES TO APHASIA TREATMENT

    PubMed Central

    Small, Steven L.; Llano, Daniel A.

    2010-01-01

    Herein, we review the basic mechanisms neural regeneration and repair and attempt to correlate the findings from animal models of stroke recovery to clinical trials for aphasia. Several randomized, controlled clinical trials that have involved manipulation of different neurotransmitter systems, including noradrenergic, dopaminergic, cholinergic and glutamatergic systems, have shown signals of efficacy. Biological approaches such as anti-Nogo and cell-replacement therapy have shown efficacy in preclinical models, but have yet to reach proof of concept in the clinic. Finally, noninvasive cortical stimulation techniques have been used in a few small trials, and have shown promising results. It appears that the efficacy of all of these platforms can be potentiated through coupling with speech-language therapy. Given this array of potential mechanisms that exist to augment and/or stimulate neural reorganization after stroke, we are optimistic that approaches to aphasia therapy will transition from compensatory models to models where brain reorganization is the goal. PMID:19818231

  9. Alternative approaches to antifungal therapies

    PubMed Central

    Mehra, T; Köberle, M; Braunsdorf, C; Mailänder-Sanchez, D; Borelli, C; Schaller, M

    2012-01-01

    The expansive use of immunosuppressive medications in fields such as transplantational medicine and oncology, the higher frequency of invasive procedures in an aging population and the HIV/AIDS pandemic have increased the frequency of systemic fungal infections. At the same time, increased resistance of pathogenic fungi to classical antifungal agents has led to sustained research efforts targeting alternative antifungal strategies. In this review, we focus on two promising approaches: cationic peptides and the targeting of fungal virulence factors. Cationic peptides are small, predominantly positively charged protein fragments which exert direct and indirect antifungal activities, one mechanism of action being the permeabilization of the fungal membrane. They include lysozyme, defensins, and cathelicidins, as well as novel synthetic peptides. Amongst fungal virulence factors, the targeting of candidal secreted aspartic proteinases seems to be a particularly promising approach. PMID:23078400

  10. Approach to Chronic Lymphocytic Meningitis.

    PubMed

    Khadilkar, Satish V; Nadkarni, Nilesh

    2015-09-01

    Chronic meningitis is a common clinical problem. Early diagnosis and appropriate therapy is important in improving the overall outcome and to prevent long-lasting sequels. As many etiological agents lead to the development of chronic lymphocytic meningitis, it is important to develop a systematic approach to the diagnosis; taking clues from history, examination and laboratory tests, to make an accurate diagnosis and institute appropriate therapy. This review focuses on the diagnostic approach towards the commonly encountered situation of chronic lymphocytic meningitis. Chronic meningitis is defined as meningeal inflammation that persists for more than 4 weeks. Chronic meningitis accounts for less than 10% of all the cases of meningitis.1 Causes of chronic lymphocytic meningitis are mainly divided into infectious and non-infectious listed in Table 1.2 Due to advancement in investigations, diseases causing chronic meningitis may be diagnosed earlier than 4 weeks and hence the definition should be considered as a rough guideline. PMID:27608867

  11. Goethean science: an alternative approach.

    PubMed

    Whitelegg, Midge

    2003-04-01

    This paper considers the science of the poet Goethe as furnishing a complementary epistemology for complementary and alternative medicine (CAM), standing alongside and very different from conventional scientific methodology. Through reference to key texts it explores the phenomenological "science of qualities" that aims to allow the scientist, through robust training, to appreciate and intuit the wholeness inherent in nature, so that Goethe could claim the human being to be the most sensitive instrument. Goethe's color theory-a challenge to Newtonian thinking-and his study of plants are explored to illustrate a profoundly different way of looking at nature that celebrates the subjective and relational as a route to perceiving the whole. Ideas toward application of Goethe's approach within CAM are considered and the relevance of this approach as an alternative methodological enquiry toward consideration of wholeness and healing are offered. PMID:12804084

  12. Transform approach to electromagnetic scattering

    NASA Technical Reports Server (NTRS)

    Mittra, R.; Ko, W. L.; Rahmat-Samii, Y.

    1979-01-01

    In this paper, a comprehensive review of the Fourier transform technique as applied to the problem of high-frequency scattering is presented and the concepts of the spectral theory of diffraction (STD) are introduced. In contrast to the more commonly employed ray-optical method for high-frequency scattering, the STD approach interprets the scattered field as the spectrum, or the Fourier transform of the induced current on the scatterer. Such an interpretation offers several important advantages: uniform nature of representation, capacity to improve and extend the ray-optical formulas in a systematic manner, and convenient accuracy tests for the results. Methods for combining integral equation methods with the Galerkin procedure and asymptotic techniques in the transform domain are described, and representative examples illustrating the application of the spectral approach are included.

  13. Computational approaches for systems metabolomics.

    PubMed

    Krumsiek, Jan; Bartel, Jörg; Theis, Fabian J

    2016-06-01

    Systems genetics is defined as the simultaneous assessment and analysis of multi-omics datasets. In the past few years, metabolomics has been established as a robust tool describing an important functional layer in this approach. The metabolome of a biological system represents an integrated state of genetic and environmental factors and has been referred to as a 'link between genotype and phenotype'. In this review, we summarize recent progresses in statistical analysis methods for metabolomics data in combination with other omics layers. We put a special focus on complex, multivariate statistical approaches as well as pathway-based and network-based analysis methods. Moreover, we outline current challenges and pitfalls of metabolomics-focused multi-omics analyses and discuss future steps for the field. PMID:27135552

  14. Different approaches of spectral analysis

    NASA Technical Reports Server (NTRS)

    Lacoume, J. L.

    1977-01-01

    Several approaches to the problem of the calculation of spectral power density of a random function from an estimate of the autocorrelation function were studied. A comparative study was presented of these different methods. The principles on which they are based and the hypothesis implied were pointed out. Some indications on the optimization of the length of the estimated correlation function was given. An example of application of the different methods discussed in this paper was included.

  15. Current approach to seronegative myasthenia.

    PubMed

    Argov, Zohar

    2011-01-01

    The group of patients with weakness or fatigue who have electrophysiological evidence of neuromuscular transmission defects, but no antibodies against either acetyl choline receptor or muscle specific kinase, need special evaluation and therapeutic consideration. Such seronegative patients may have low affinity antibodies but may also be late onset of a congenital myasthenic syndrome. This review discuss the practical approach toward the condition of seronegative myasthenia. PMID:20852878

  16. Jellyfish Stings: A Practical Approach.

    PubMed

    Lakkis, Najla A; Maalouf, Grace J; Mahmassani, Dina M

    2015-09-01

    Jellyfish have a worldwide distribution. Their stings can cause different reactions, ranging from cutaneous, localized, and self-limited to serious systemic or fatal ones, depending on the envenoming species. Several first aid treatments are used to manage such stings but few have evidence behind their use. This review of the literature describes and discusses the different related first aid and treatment recommendations, ending with a summarized practical approach. Further randomized controlled trials in this field are needed. PMID:25935311

  17. Recommended approach to sofware development

    NASA Technical Reports Server (NTRS)

    Mcgarry, F. E.; Page, J.; Eslinger, S.; Church, V.; Merwarth, P.

    1983-01-01

    A set of guideline for an organized, disciplined approach to software development, based on data collected and studied for 46 flight dynamics software development projects. Methods and practices for each phase of a software development life cycle that starts with requirements analysis and ends with acceptance testing are described; maintenance and operation is not addressed. For each defined life cycle phase, guidelines for the development process and its management, and the products produced and their reviews are presented.

  18. Ares I Integrated Test Approach

    NASA Technical Reports Server (NTRS)

    Taylor, Jim

    2008-01-01

    This slide presentation reviews the testing approach that NASA is developing for the Ares I launch vehicle. NASA is planning a complete series of development, qualification and verification tests. These include: (1) Upper stage engine sea-level and altitude testing (2) First stage development and qualification motors (3) Upper stage structural and thermal development and qualification test articles (4) Main Propulsion Test Article (MPTA) (5) Upper stage green run testing (6) Integrated Vehicle Ground Vibration Testing (IVGVT) and (7) Aerodynamic characterization testing.

  19. [Psychosomatic approach for chronic migraine].

    PubMed

    Hashizume, Masahiro

    2011-11-01

    From psychosomatic view point, the psychological or social stresses and depressive or anxiety disorders are very important factors in the course and the maintenance for migraine patients. These factors are very complex, and often lead the migraine becoming chronic. In the psychosomatic approach, not only the physical assessment for chronic migraine but also the assessments for stress and mental states are done. As the psychosomatic therapies for chronic migraine, autogenic training, biofeedback therapy and cognitive therapy are effective. PMID:22277516

  20. The enter-educate approach.

    PubMed

    Piotrow, P T; Coleman, P L

    1992-03-01

    This article describes how the Population Communication Services (PCS) has seized on the "enter-educate" approach, the blending of popular entertainment with social messages, to change reproductive health behavior. The enter-educate approach spreads its message through songs, soap operas, variety shows, and other types of popular entertainment mediums. Because they entertain, enter-educate projects can capture the attention of an audience -- such as young people -- who would otherwise scorn social messages. And the use of population mediums makes it possible to reach a variety of audiences. Funded by USAID, PCS began its first enter-educate project in response to the increasing number of teenage pregnancies in Latin America. PCS developed 2 songs and videos, which featured popular teenage singers to serve as role models, to urge abstinence. The songs became instant hits. Since then, PCS has mounted more then 80 major projects in some 40 countries. Highlights of programs range from a successful multi-media family planning campaign in Turkey to humorous television ads in Brazil promoting vasectomy. Recently, PCS initiated projects to teach AIDS awareness. At the core of the enter-educate approach is the social learning theory which holds that much behavior is learned through the observation of role-models. Health professionals work alongside entertainers to produce works that have audience appeal and factual social messages. The enter-educate approach works because it is popular, pervasive, personal, persuasive, and profitable. PCS has found that enter-educate programs pay for themselves through cost sharing and cost recovery. PMID:12284960