1,723 research outputs found

    Efficient Transport Protocol for Networked Haptics Applications

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    The performance of haptic application is highly sensitive to communication delays and losses of data. It implies several constraints in developing networked haptic applications. This paper describes a new internet protocol called Efficient Transport Protocol (ETP), which aims at developing distributed interactive applications. TCP and UDP are transport protocols commonly used in any kind of networked communication, but they are not focused on real time application. This new protocol is focused on reducing roundtrip time (RTT) and inter packet gap (IPG). ETP is, therefore, optimized for interactive applications which are based on processes that are continuously exchanging data.ETP protocol is based on a state machine that decides the best strategies for optimizing RTT and IPG. Experiments have been carried out in order to compare this new protocol and UDP

    Environmental complexity: A buffer against stress in the domestic chick

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    Birds kept in commercial production systems can be exposed to multiple stressors from early life and this alters the development of different morphological, immunological and behavioural indicators. We explore the hypothesis that provision of a complex environment during early life, better prepares birds to cope with stressful events as well as buffers them against future unpredictable stressful episodes. In this study, 96 one day old pullets were randomly distributed in eight pens (12 birds/pen). Half of the chicks (N = 48) were assigned to a Complex Environment (CENV: with perches, a dark brooder etc.) the others to a Simple Environment (SENV: without enrichment features). Half of the birds from each of these treatments were assigned to a No Stress (NSTR, 33C) or to an acute Cold Stress (CSTR, 18–20C) treatment during six hours on their second day of life. At four weeks of age, chicks with these four different backgrounds were exposed to an Intermittent Stressful Challenges Protocol (ISCP). In an immunological test indicative of pro-inflammatory status Phytohe-magglutinin-P (PHA-P), the response of CSTR birds was ameliorated by rearing chicks in a CENV as they had a similar response to NSTR chicks and a significantly better pro-inflammatory response than those CSTR birds reared in a SENV (five days after the CSTR treatment was applied). A similar better response when coping with new challenges (the ISCP) was observed in birds reared in a CENV compared to those from a SENV. Birds reared in the CENV had a lower heterophil/lymphocyte ratio after the ISCP than birds reared in SENV, independently of whether or not they had been exposed to CSTR early in life. No effects of stress on general behaviour were detected, however, the provision of a CENV increased resting behaviour, which may have favoured stress recover. Additionally, we found that exposure to cold stress at an early age might have rendered birds more vulnerable to future stressful events. CSTR birds had lower humoral immune responses (sheep red blood cells induced antibodies) after the ISCP and started using elevated structures in the CENV later compared to their NSTR conspecifics. Our study reflects the importance of the early provision of a CENV in commercial conditions to reduce negative stress-related effects. Within the context of the theory of adaptive plasticity, our results suggest that the early experience of the birds had long lasting effects on the modulation of their phenotypes.Fil: Campderrich, Irene. Centro de Investigación. Neiker - Tecnalia; España. Swedish University of Agricultural Sciences; SueciaFil: Nazar, Franco Nicolas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Wichman, Anette. Swedish University of Agricultural Sciences; SueciaFil: Marin, Raul Hector. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Estevez, Inma. Centro de Investigación. Neiker - Tecnalia; EspañaFil: Keeling, Linda J.. Swedish University of Agricultural Sciences; Sueci

    An individually fitted physical barrier device as a tool to restrict the birds’spatial access: can their use alter behavioral responses?

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    In this work we introduce an hp finite element method for two-dimensional Poisson problems on curved domains using curved elements. We obtain a priori  error estimates and define a local a posteriori error estimator of residual type.We show,  under appropriate assumptions about the curved domain, the globalreliability and the local efficiency of the esimator. More precisely, we prove that theestimator is equivalent to the energy norm of the error up to higher order terms. The equivalence constant of the efficiency estimate depends on the polynomial degree.We also present an hp adaptive algorithm and several numerical tests which show the performance of the adaptive strategy.Fil: Pellegrini, Stefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Marin, Raul Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Guzmán, Diego Alberto. Aarhus University. Aarhus Institute Of Advanced Studies.; Dinamarca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentin

    Ciudad y territorio, ortodoxia y disidencia religiosa en el Imperio romano cristiano (ss. IV-V)

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    Tras una introducción en la que se presentan algunas aproximaciones sociológicas al estudio del fenómeno de la lenta cristianización del campo romano -en comparación con la de los ámbitos urbanos- se estudia la incidencia en este fenómeno de las tensiones y conflictos de poder entre los principales agentes de la cristianización del Imperio: autoridad imperial, jerarquías eclesiásticas, homines sancti carismáticos situados en los límites de la Iglesia institucional y grandes propietarios rurales. Tales tensiones adoptaron en ocasiones la forma de un conflicto entre "ortodoxia" y "heterodoxia religiosa". Hacia principios del siglo V se ha forjado una geografía simbólica en la que la ciudad es la fortaleza de la ortodoxia cristiana y el campo el ámbito privilegiado de la disidencia religiosa

    End-to-end congestion control protocols for remote programming of robots, using heterogeneous networks: A comparative analysis

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    There are many interesting aspects of Internet Telerobotics within the network robotics context, such as variable bandwidth and time-delays. Some of these aspects have been treated in the literature from the control point of view. Moreover, only a little work is related to the way Internet protocols can help to minimize the effect of delay and bandwidth fluctuation on network robotics. In this paper, we present the capabilities of TCP, UDP, TCP Las Vegas, TEAR, and Trinomial protocols, when performing a remote experiment within a network robotics application, the UJI Industrial Telelaboratory. Comparative analysis is presented through simulations within the NS2 platform. Results show how these protocols perform in two significant situations within the network robotics context, using heterogeneous wired networks: (1) an asymmetric network when controlling the system through a ADSL connection, and (2) a symmetric network using the system on Campus. Conclusions show a set of characteristics the authors of this paper consider very important when designing an End-to-End Congestion Control transport protocol for Internet Telerobotics

    Resíduos de aflatoxina B1 em fígado de codornas japonesas (Coturnix japonica) expostas a alimentos contaminados e à corticosterona exógena

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    The combined effect of aflatoxin B1 (AFB1 ) exposition and stress induced by corticosterone (CORT) upon the residual aflatoxin levels in livers of Japanese quail was examined. A total of 144 Japanese quail (Coturnix japonica) were divided into 6 treatments with 6 replicates per treatment, each containing 2 males and 2 females. The different treatments resulted from the combination of the presence or absence of CORT in drinking water (5 mg/L) with the presence or absence of AFB1 supplementation (100 or 500 ng/g). Dietary treatments were offered from 5 to 11 weeks of age. The different diets were: Treatment (T) 1: basal diet (B) AFB1 (15 ng/g); T2: B plus AFB1 (100 ng/g); T3: B plus AFB1 (500 ng/g); T4: B plus CORT (5 mg/L); T5: B plus AFB1 (100 ng/g) and CORT (5 mg/L); and T6: B plus AFB1 (500 ng/g) and CORT (5 mg/L). The residual levels of AFB1 were remarkably higher in livers of birds fed with AFB1 in comparison with those belonging to the group that received a combination of AFB1 and CORT (P< 0.05). A plausible explanation about the facts that could be responsible for observed reduction in the toxin carryover in liver was suggested. These results are very striking and may constitute the start point for a series of studies that aim to elucidate the precise influence of hypothalamic-pituitary-adrenal axis (HPA) response to stress in birds exposed to AFB.Estudou-se o efeito combinado da exposição à aflatoxina B1 (AFB1 ) e o estresse induzido por corticosterona (CORT) sobre os níveis de residuais de AFB1 em fígados de codornas japonesas. Um total de 144 codornas japonesas (Coturnix japonica) foram divididas em 6 tratamentos com 6 repetições por tratamento, cada uma contendo 2 machos e 2 fêmeas. As dietas dos tratamentos foram oferecidas da 5ª até a 11ª semana de idade. Os diferentes tratamentos resultaram da combinação da presença ou ausência de CORT na água de beber (5 mg / L), com a presença ou ausência de suplementação AFB1 (100 ou 500 ng /g) As dietas diferentes foram: Tratamento (T) 1: dieta basal (B) AFB1 (15 ng/g); T2: B mais AFB1 (100 ng / g); T3: B mais AFB1 (500 ng / g); T4: B mais CORT (5 mg / L); T5: B mais AFB1 (100 ng / g) e CORT (5 mg / L), e T6: B mais AFB1 (500 ng / g) e CORT (5 mg / L). Os níveis residuais de AFB1 foram significativamente mais elevados em fígados de aves alimentadas com AFB1 em comparação com os que pertencem ao grupo que recebeu uma combinação de AFB1 e CORT (P< 0,05). Sugere-se uma possível explicação para a redução dos níveis da toxina observada naqueles animais submetidos a dieta com CORT. Estes resultados constituem-se de um ponto de início para uma série de estudos que visam a elucidar a influência da resposta do eixo hipotalâmico-hipofisário-adrenais (HPA) ao stress em aves expostas a AFB.Fil: Magnoli, Alejandra Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Chiacchiera, Stella Maris. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rosa, Carlos Alberto da Rocha. Universidade Federal Rural de Rio de Janeiro; BrasilFil: Dalcero, Ana Maria. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marin, Raul Hector. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Convective heat transfer modelling in dry-running polymer spur gears

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    Heat convection is an important phenomenon in the process of cooling polymer spur gears running in dry conditions, which ultimately affects the strength of the gears. In order to gain some insight into this phenomenon, a numerical heat convection model for polymer spur gears is proposed in this work, which is based on a detailed CFD simulation of the gears in operating conditions and it allows us to investigate the heat convection through their external surfaces. The performance of this numerical model is illustrated with several examples, in which a parametric study has been conducted to observe the variation of the heat transfer coefficients with the face width and the angular speed of the gears. The results obtained from this parametric study are compared to those obtained from a representative classical heat convection model, observing that the relative differences between them in terms of heat transfer coefficients can be as high as 125%. Finally, a new optimized heat convection model for polymer spur gears running in dry conditions is proposed, in which the convective heat transfer coefficients for the external surfaces of the gears are calculated from empirical equations based on the Newton’s law of cooling. This optimized model has lower computational cost than the numerical one, while it provides an important increase of the accuracy of the classical heat convection models, reducing the maximum relative differences to 10%.Funding for open access charge: CRUE-Universitat Jaume

    Japanese quail classified by their permanence in proximity to a high or low density of conspecifics: a search for underpinning variables

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    Test of sociality in poultry is mainly based on the bird's individual ability to make quick social discriminations. In recent years, a density-related permanence (DRP) test has been developed that enables us to classify young birds (while in groups) according to their individual permanence in proximity to either a high or low density of conspecifics (HD or LD, respectively). Thus, the result of the classification depends not only on the bird's individual response but also on the outcome of the social interactions within the whole group. The birds' performance in DRP was associated with underlying differences in social responses of their individuals. Quails in homogeneous groups of LD residents responded with less compact groups and higher levels of agonistic interactions to the presence of an intruder and showed higher levels of agonistic interactions among cage-mates than the homogeneous groups of HD birds. An acute stressor also induced a higher corticosterone response in the LD birds than in their HD counterparts. The present study addressed the question of whether contrasting DRP performance by Japanese quail can also reflect underlying differences in fearfulness and social reinstatement responses. Thus, LD and HD categorized juvenile birds underwent one of the following tests: tonic immobility (TI), open-field (OF), or a one-way runway. Results showed that HD birds required more inductions and developed shorter responses (P ≤ 0.05) in the TI test and walked more, faster, and greater distances in the OF (P ≤ 0.05) than their LD counterparts. No differences between groups were found in short social reinstatement responses. The present findings suggest that underlying fearfulness is lower in the HD than in the LD birds. A reduced fearfulness could be regarded as an additional favorable trait of the HD-classified quail to cope with environmental challenging situations.Fil: Guzmán, Diego Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; ArgentinaFil: Kembro, Jackelyn Melissa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; ArgentinaFil: Marin, Raul Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; Argentin

    Asistencia en oncología pediátrica : caso Plan Esperanza del Instituto Nacional de Enfermedades Neoplásicas (INEN)

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    La presente investigación titulada “Asistencia en Oncología Pediátrica: Caso Plan Esperanza del Instituto Nacional de Enfermedades Neoplásicas (INEN)” permite conocer los servicios a los que acceden los niños, niñas y adolescentes que padecen la enfermedad del cáncer. El tratamiento del cáncer en los niños es muy diferente al tratamiento de los adultos, ya que, en el caso de los menores, es más evidente el hecho de que este mal debilita las defensas del organismo contra otras enfermedades. El principal tipo de cáncer infantil es la leucemia linfocítica aguda, más conocida como LLA. En el Perú, existen 150 casos de cáncer por 100000 habitantes, lo cual convierte a esta enfermedad en la segunda causa de mortalidad a nivel nacional y se estima que el 75% de los casos se diagnostican en etapa avanzada y principalmente en Lima. Por tal razón, el Plan Esperanza es una iniciativa del Estado peruano para atender integralmente a la población afectada por esta enfermedad y brindarle el acceso a los servicios oncológicos en el Perú de acuerdo al desarrollo tecnológico y la disponibilidad de recursos. El objetivo general de esta investigación es conocer la asistencia que brinda el Plan Esperanza a los niños y adolescentes enfermos de cáncer en Oncología Pediátrica del Instituto Nacional de Enfermedades Neoplásicas, entre los años 2013 y 2015; para ello, se analizan los servicios que ofrece este programa como aporte para mejorar la calidad de vida de los pacientes afectados. Con la información recogida a partir de la entrevista con los padres de los niños beneficiarios del Plan Esperanza, se logrará mejorar los servicios y fortalecer las buenas prácticas.The present research entitled "Assistance in Pediatric Oncology: Plan Esperanza Case of the National Institute of Neoplastic Diseases (INEN)" allows us to know the services that children and adolescents suffering from cancer have access to. The treatment of cancer in children is very different from the treatment of adults because it weakens the body's defenses against other diseases. The main type of childhood cancer is acute lymphocytic leukemia, better known as ALL. In Peru, there are 150 cases of cancer per 100,000 inhabitants, being the second leading cause of death at the national level and it is estimated that 75% of cases are diagnosed at an advanced stage and mainly in Lima. For this reason, the Plan Esperanza is an initiative of the Peruvian State to fully serve the population affected by this disease and provide them with access to cancer services in Peru according to technological development and the availability of resources. The general objective of this research is to know the assistance provided by the Plan Esperanza to children and adolescents suffering from cancer in Pediatric Oncology of the National Institute of Neoplastic Diseases between 2013 and 2015; analyzing the services offered by this program as a contribution to improve the quality of life of affected patients. With the information collected from the parents of the beneficiaries of the Plan Esperanza will be able to improve services and strengthen good practices.Tesi
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