1,533 research outputs found

    Crescimento E Produção De Antúrio Em Resposta A Cobertura Do Solo Com Serragem De Madeira

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    The objectives of the study were to analyze the effect of sawdust mulch on the: (1) soil characteristics; (2) growth and flower yield of the anthurium cv. ‘Apalai’. Assay was conducted in a totally randomized design in subdivided plots, with five treatments and eight replications. The treatment consisted of five volumes of sawdust 0, 20, 40, 60 and 80L m-2, distributed over the bed, every three months. Soil, plants and flower stalks were evaluated during two years. Soil temperature, moisture, organic matter, bulk density and water retention conditions were improved, while the leaf area of plants and the yield of flower stalks were increased when the soil were mulched with sawdust. In addition to increasing soil organic matter, however, no change occurred in the level of nutrients in plants. Sawdust also improved the dimension of flower stalks. Application of 40L m-2 of sawdust every three months is recommended. © (2016) Universidade Federal de Santa Maria. All rights reserved.46344044

    Cosmological particle production, causal thermodynamics, and inflationary expansion

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    Combining the equivalence between cosmological particle creation and an effective viscous fluid pressure with the fact that the latter represents a dynamical degree of freedom within the second-order Israel-Stewart theory for imperfect fluids, we reconsider the possibility of accelerated expansion in fluid cosmology. We find an inherent self-limitation for the magnitude of an effective bulk pressure which is due to adiabatic (isentropic) particle production. For a production rate which depends quadratically on the Hubble rate we confirm the existence of solutions which describe a smooth transition from inflationary to noninflationary behavior and discuss their interpretation within the model of a decaying vacuum energy density. An alternative formulation of the effective imperfect fluid dynamics in terms of a minimally coupled scalar field is given. The corresponding potential is discussed and an entropy equivalent for the scalar field is found.Comment: 16 pages, revtex file, submitted to Phys. Rev.

    Conformal symmetry and deflationary gas universe

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    We describe the ``deflationary'' evolution from an initial de Sitter phase to a subsequent Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) period as a specific non-equilibrium configuration of a self-interacting gas. The transition dynamics corresponds to a conformal, timelike symmetry of an ``optical'' metric, characterized by a refraction index of the cosmic medium which continously decreases from a very large initial value to unity in the FLRW phase.Comment: 10 pages, to appear in "Exact Solutions and Scalar Fields in Gravity: Recent Developments", ed. by A. Macias, J. Cervantes-Cota, and C. L\"ammerzahl, Kluwer Academic Publishers 200

    Collisional equilibrium, particle production and the inflationary universe

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    Particle production processes in the expanding universe are described within a simple kinetic model. The equilibrium conditions for a Maxwell-Boltzmann gas with variable particle number are investigated. We find that radiation and nonrelativistic matter may be in equilibrium at the same temperature provided the matter particles are created at a rate that is half the expansion rate. Using the fact that the creation of particles is dynamically equivalent to a nonvanishing bulk pressure we calculate the backreaction of this process on the cosmological dynamics. It turns out that the `adiabatic' creation of massive particles with an equilibrium distribution for the latter necessarily implies power-law inflation. Exponential inflation in this context is shown to become inconsistent with the second law of thermodynamics after a time interval of the order of the Hubble time.Comment: 19 pages, latex, no figures, to appear in Phys.Rev.

    Nonsingular FRW cosmology and nonlinear electrodynamics

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    The possibility to avoid the cosmic initial singularity as a consequence of nonlinear effects on the Maxwell eletromagnetic theory is discussed. For a flat FRW geometry we derive the general nonsingular solution supported by a magnetic field plus a cosmic fluid and a nonvanishing vacuum energy density. The nonsingular behavior of solutions with a time-dependent Λ(t)\Lambda(t)-term are also examined. As a general result, it is found that the functional dependence of Λ(t)\Lambda(t) can uniquely be determined only if the magnetic field remains constant. All these models are examples of bouncing universes which may exhibit an inflationary dynamics driven by the nonlinear corrections of the magnetic field.Comment: 20 pages, 7 figure

    Power spectrum and correlation function errors: Poisson vs. Gaussian shot noise

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    Poisson distributed shot noise is normally considered in the Gaussian limit in cosmology. However, if the shot noise is large enough and the correlation function/power spectrum conspires, the Gaussian approximation mis-estimates the errors and their covariance significantly. The power spectrum, even for initially Gaussian densities,acquires cross correlations which can be large, while the change in the correlation function error matrix is diagonal except at zero separation. Two and three dimensional power law correlation function and power spectrum examples are given. These corrections appear to have a large effect when applied to galaxy clusters, e.g. for SZ selected galaxy clusters in 2 dimensions. This can increase the error estimates for cosmological parameter estimation and consequently affect survey strategies, as the corrections are minimized for surveys which are deep and narrow rather than wide and shallow. In addition, a rewriting of the error matrix for the power spectrum/correlation function is given which eliminates most of the Bessel function dependence (in two dimensions) and all of it (in three dimensions), which makes the calculation of the error matrix more tractable. This applies even when the shot noise is in the (usual) Gaussian limit.Comment: 22 pages, 4 figures, 3 equations corrected/figures updated, results unchange

    Brans-Dicke Theory and primordial black holes in Early Matter-Dominated Era

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    We show that primordial black holes can be formed in the matter-dominated era with gravity described by the Brans-Dicke theory. Considering an early matter-dominated era between inflation and reheating, we found that the primordial black holes formed during that era evaporate at a quicker than those of early radiation-dominated era. Thus, in comparison with latter case, less number of primordial black holes could exist today. Again the constraints on primordial black hole formation tend towards the larger value than their radiation-dominated era counterparts indicating a significant enhancement in the formation of primordial black holes during the matter-dominaed era.Comment: 9 page

    Epidemiological And Genetic Characteristics Associated With The Severity Of Acute Viral Bronchiolitis By Respiratory Syncytial Virus

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    Objective: to assess the epidemiological and genetic factors associated with severity of acute viral bronchiolitis (AVB) by respiratory syncytial virus (RSV). Data source: the key words "bronchiolitis", "risk factor", "genetics" and "respiratory syncytial virus", and all combinations among them were used to perform a search in the PubMed, SciELO, and Lilacs databases, of articles published after the year 2000 that included individuals younger than 2 years of age. Data synthesis: a total of 1,259 articles were found, and their respective summaries were read. Of these, 81 were selected, which assessed risk factors for the severity of AVB, and were read in full; the 60 most relevant studies were included. The epidemiologic factors associated with AVB severity by RSV were prematurity, passive smoking, young age, lack of breastfeeding, chronic lung disease, congenital heart disease, male gender, ethnicity, viral coinfection, low weight at admission, maternal smoking during pregnancy, atopic dermatitis, mechanical ventilation in the neonatal period, maternal history of atopy and/or asthma during pregnancy, season of birth, low socioeconomic status, Down syndrome, environmental pollution, living at an altitude > 2,500 meters above sea level, and cesarean section birth. Conversely, some children with severe AVB did not present any of these risk factors. In this regard, recent studies have verified the influence of genetic factors on the severity of AVB by RSV. Polymorphisms of the TLRs, RANTES, JUN, IFNA5, NOS2, CX3CR1, ILs, and VDR genes have been shown to be associated with more severe evolution of AVB by RSV. Conclusion: the severity of AVB by RSV is a phenomenon that depends on the varying degrees of interaction among epidemiological, environmental, and genetic variables. © 2013 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.896531543Chávez-Bueno, S., Mejías, A., Welliver, R.C., Respiratory syncytial virus bronchiolitis: Current and future strategies for treatment and prophylaxis (2006) Treat Respir Med, 5, pp. 483-494Ogra, P.L., Respiratory syncytial virus: The virus, the disease and the immune response (2004) Paediatr Respir Rev, 5, pp. 119-S126Stockman, L.J., Curns, A.T., Anderson, L.J., Fischer-Langley, G., Respiratory syncytial virus-associated hospitalizations among infants and young children in the United States, 1997-2006 (2012) Pediatr Infect Dis J, 31, pp. 5-9Leader, S., Kohlhase, K., Recent trends in severe respiratory syncytial virus (RSV) among US infants, 1997 to 2000 (2003) J Pediatr, 143, pp. 127-S132Ranmuthugala, G., Brown, L., Lidbury, B.A., Respiratory syncytial virus - The unrecognised cause of health and economic burden among young children in Australia (2011) Commun Dis Intell, 35, pp. 177-184Simões, E.A., Carbonell-Estrany, X., Impact of severe disease caused by respiratory syncytial virus in children living in developed countries (2003) Pediatr Infect Dis J, 22, pp. 13-S18. , discussion S18-20Albernaz, E.P., Menezes, A.M., César, J.A., Victora, C.G., Barros, F.C., Halpern, R., Risk factors associated with hospitalization for bronchiolitis in the post-neonatal period (2003) Rev Saude Publica, 37, pp. 485-493Deshpande, S.A., Northern, V., The clinical and health economic burden of respiratory syncytial virus disease among children under 2 years of age in a defined geographical area (2003) Arch Dis Child, 88, pp. 1065-1069Fryzek, J.P., Martone, W.J., Groothuis, J.R., Trends in chronologic age and infant respiratory syncytial virus hospitalization: An 8-year cohort study (2011) Adv Ther, 28, pp. 195-201Sung, C.C., Chi, H., Chiu, N.C., Huang, D.T., Weng, L.C., Wang, N.Y., Viral etiology of acute lower respiratory tract infections in hospitalized young children in Northern Taiwan (2011) J Microbiol Immunol Infect, 44, pp. 184-190García, M.L., Ordobás Gabin, M., Calvo Reya, C., González Alvarez, M., Aguilar Ruiz, J., Arregui Sierra, A., Viral infection of the lower respiratory tract in hospitalized infants: Etiology, clinical features and risk factors (2001) An Esp Pediatr, 55, pp. 101-107Riccetto, A.G., Ribeiro, J.D., Silva, M.T., Almeida, R.S., Arns, C.W., Baracat, E.C., Respiratory syncytial virus (RSV) in infants hospitalized for acute lower respiratory tract disease: Incidence and associated risks (2006) Braz J Infect Dis, 10, pp. 357-361Salomão Junior, J.B., Gardinassi, L.G., Simas, P.V., Bittar, C.O., Souza, F.P., Rahal, P., Human respiratory syncytial virus in children hospitalized for acute lower respiratory infection (2011) J Pediatr (Rio J), 87, pp. 219-224Sly, P.D., Jones, C.M., Viral co-detection in infants hospitalized with respiratory disease: Is it important to detect? (2011) J Pediatr (Rio J), 87, pp. 277-280Miller, E.K., Williams, J.V., Gebretsadik, T., Carroll, K.N., Dupont, W.D., Mohamed, Y.A., Host and viral factors associated with severity of human rhinovirus-associated infant respiratory tract illness (2011) J Allergy Clin Immunol, 127, pp. 883-891Nascimento, M.S., Souza, A.V., Ferreira, A.V., Rodrigues, J.C., Abramovici, S., Silva Filho, L.V., High rate of viral identification and coinfections in infants with acute bronchiolitis (2010) Clinics (Sao Paulo), 65, pp. 1133-1137Groothuis, J.R., Fryzek, J.P., Makari, D., Steffey, D., Martone, W.J., Respiratory syncytial virus hospitalization trends in infants with chronic lung disease of infancy, 1998-2008 (2011) Clin Epidemiol, 3, pp. 245-250Gouyon, J.B., Rozé, J.C., Guillermet-Fromentin, C., Glorieux, I., Adamon, L., Di Maio, M., Hospitalizations for respiratory syncytial virus bronchiolitis in preterm infants at < 33 weeks gestation without bronchopulmonary dysplasia: The CASTOR study (2012) Epidemiol Infect, 15, pp. 1-11Semple, M.G., Taylor-Robinson, D.C., Lane, S., Smyth, R.L., Household tobacco smoke and admission weight predict severe bronchiolitis in infants independent of deprivation: Prospective cohort study (2011) PLoS One, 6, p. 22425Koehoorn, M., Karr, C.J., Demers, P.A., Lencar, C., Tamburic, L., Brauer, M., Descriptive epidemiological features of bronchiolitis in a population-based cohort (2008) Pediatrics, 122, pp. 1196-1203Ochoa Sangrador, C., González De Dios, J., Idoneidad y Adecuación). Consensus conference on acute bronchiolitis (VI): Prognosis of acute bronchiolitis. Review of scientific evidence (2010) An Pediatr (Barc), 72 (354), pp. e1-3634. , Grupo de Revisión del Proyecto aBREVIADo (BRonquiolitis-Estudio de VariabilidadGrimwood, K., Cohet, C., Rich, F.J., Cheng, S., Wood, C., Redshaw, N., Risk factors for respiratory syncytial virus bronchiolitis hospital admission in New Zealand (2008) Epidemiol Infect, 136, pp. 1333-1341López Guinea, A., Casado Flores, J., Martín Sobrino, M.A., Espínola Docio, B., De La Calle Cabrera, T., Serrano, A., García Teresa, M.A., Severe bronchiolitis. Epidemiology and clinical course of 284 patients (2007) An Pediatr (Barc), 67, pp. 116-122Chan, P.W., Lok, F.Y., Khatijah, S.B., Risk factors for hypoxemia and respiratory failure in respiratory syncytial virus bronchiolitis (2002) Southeast Asian J Trop Med Public Health, 33, pp. 806-810Garcia, C.G., Bhore, R., Soriano-Fallas, A., Trost, M., Chason, R., Ramilo, O., Mejias, A., Risk factors in children hospitalized with RSV bronchiolitis versus non-RSV bronchiolitis (2010) Pediatrics, 126, pp. 1453-e1460Chatzimichael, A., Tsalkidis, A., Cassimos, D., Gardikis, S., Tripsianis, G., Deftereos, S., The role of breastfeeding and passive smoking on the development of severe bronchiolitis in infants (2007) Minerva Pediatr, 59, pp. 199-206Jones, L.L., Hashim, A., McKeever, T., Cook, D.G., Britton, J., Leonardi-Bee, J., Parental and household smoking and the increased risk of bronchitis, bronchiolitis and other lower respiratory infections in infancy: Systematic review and meta-analysis (2011) Respir Res, 12, p. 5Bradley, J.P., Bacharier, L.B., Bonfiglio, J., Schechtman, K.B., Strunk, R., Storch, G., Severity of respiratory syncytial virus bronchiolitis is affected by cigarette smoke exposure and atopy (2005) Pediatrics, 115, pp. 7-e14Hervás, D., Reina, J., Yañez, A., Del Valle, J.M., Figuerola, J., Hervás, J.A., Epidemiology of hospitalization for acute bronchiolitis in children: Differences between RSV and non-RSV bronchiolitis (2012) Eur J Clin Microbiol Infect Dis, 31, pp. 1975-1981Oñoro, G., Pérez Suárez, E., Iglesias Bouzas, M.I., Serrano, A., Martínez De Azagra, A., Severe bronchiolitis. Changes in epidemiology and respiratory support (2011) An Pediatr (Barc), 74, pp. 371-376Damore, D., Mansbach, J.M., Clark, S., Ramundo, M., Camargo Jr., C.A., Prospective multicenter bronchiolitis study: Predicting intensive care unit admissions (2008) Acad Emerg Med, 15, pp. 887-894Papoff, P., Moretti, C., Cangiano, G., Bonci, E., Roggini, M., Pierangeli, A., Incidence and predisposing factors for severe disease in previously healthy term infants experiencing their first episode of bronchiolitis (2011) Acta Paediatr, 100, pp. 17-e23Vidaurreta, S.M., Marcone, D.N., Ellis, A., Ekstrom, J., Cukier, D., Videla, C., Acute viral respiratory infection in children under 5 years: Epidemiological study in two centers in Buenos Aires, Argentina (2011) Arch Argent Pediatr, 109, pp. 296-304Dornelles, C.T., Piva, J.P., Marostica, P.J., Nutritional status, breastfeeding, and evolution of infants with acute viral bronchiolitis (2007) J Health Popul Nutr, 25, pp. 336-343Al-Shehri, M.A., Sadeq, A., Quli, K., Bronchiolitis in Abha, Southwest Saudi Arabia: Viral etiology and predictors for hospital admission (2005) West Afr J Med, 24, pp. 299-304Che, D., Nicolau, J., Bergounioux, J., Perez, T., Bitar, D., Bronchiolitis among infants under 1 year of age in France: Epidemiology and factors associated with mortality (2012) Arch Pediatr, 19, pp. 700-706Fjaerli, H.O., Farstad, T., Bratlid, D., Hospitalisations for respiratory syncytial virus bronchiolitis in Akershus, Norway, 1993-2000: A population-based retrospective study (2004) BMC Pediatr, 4, p. 25Meissner, H.C., Selected populations at increased risk from respiratory syncytial virus infection (2003) Pediatr Infect Dis J, 22, pp. 40-S45Riccetto, A.G., Silva, L.H., Spilki, F.R., Morcillo, A.M., Arns, C.W., Baracat, E.C., Genotypes and clinical data of respiratory syncytial virus and metapneumovirus in Brazilian infants: A new perspective (2009) Braz J Infect Dis, 13, pp. 35-39D'Elia, C., Siqueira, M.M., Portes, S.A., Sant'Anna, C.C., Respiratory syncytial virus - Associated lower respiratory tract infections in hospitalized infants (2005) Rev Soc Bras Med Trop, 38, pp. 7-10Weigl, J.A., Puppe, W., Schmitt, H.J., Variables explaining the duration of hospitalization in children under two years of age admitted with acute airway infections: Does respiratory syncytial virus have a direct impact? (2004) Klin Padiatr, 216, pp. 7-15Brand, H.K., De Groot, R., Galama, J.M., Brouwer, M.L., Teuwen, K., Hermans, P.W., Infection with multiple viruses is not associated with increased disease severity in children with bronchiolitis (2012) Pediatr Pulmonol, 47, pp. 393-400De Paulis, M., Gilio, A.E., Ferraro, A.A., Ferronato, A.E., Do Sacramento, P.R., Botosso, V.F., Severity of viral coinfection in hospitalized infants with respiratory syncytial virus infection (2011) J Pediatr (Rio J), 87, pp. 307-313Jartti, T., Söderlund-Venermo, M., Hedman, K., Ruuskanen, O., Mäkelä, M.J., New molecular virus detection methods and their clinical value in lower respiratory tract infections in children (2013) Paediatr Respir Rev, 14, pp. 38-45Carroll, K.N., Gebretsadik, T., Griffin, M.R., Dupont, W.D., Mitchel, E.F., Wu, P., Maternal asthma and maternal smoking are associated with increased risk of bronchiolitis during infancy (2007) Pediatrics, 119, pp. 1104-1112Bloemers, B.L., Van Furth, A.M., Weijerman, M.E., Gemke, R.J., Broers, C.J., Van Den Ende, K., Down syndrome: A novel risk factor for respiratory syncytial virus bronchiolitis - A prospective birth-cohort study (2007) Pediatrics, 120, pp. 1076-e1081Karr, C., Lumley, T., Schreuder, A., Davis, R., Larson, T., Ritz, B., Effects of subchronic and chronic exposure to ambient air pollutants on infant bronchiolitis (2007) Am J Epidemiol, 165, pp. 553-560Choudhuri, J.A., Ogden, L.G., Ruttenber, A.J., Thomas, D.S., Todd, J.K., Simoes, E.A., Effect of altitude on hospitalizations for respiratory syncytial virus infection (2006) Pediatrics, 117, pp. 349-356Moore, H.C., De Klerk, N., Holt, P., Richmond, P.C., Lehmann, D., Hospitalisation for bronchiolitis in infants is more common after elective caesarean delivery (2012) Arch Dis Child, 97, pp. 410-414Thomsen, S.F., Stensballe, L.G., Skytthe, A., Kyvic, K.O., Backer, V., Bisgaard, H., Increased concordance of severe respiratory syncytial virus infection in identical twins (2008) Pediatrics, 121, pp. 493-496Tal, G., Mandelberg, A., Dalal, I., Cesar, K., Somekh, E., Tal, A., Association between common Toll-like receptor 4 mutations and severe respiratory syncytial virus disease (2004) J Infect Dis, 189, pp. 2057-2063Douville, R.N., Lissitsyn, Y., Hirschfeld, A.F., Becker, A.B., Kozyrskyj, A.L., Liem, J., TLR4 Asp299Gly and Thr399Ile polymorphisms: No impact on human immune responsiveness to LPS or respiratory syncytial virus (2010) PLoS One, 5, p. 12087Löfgren, J., Marttila, R., Renko, M., Rämet, M., Hallman, M., Toll-like receptor 4 Asp299Gly polymorphism in respiratory syncytial virus epidemics (2010) Pediatr Pulmonol, 45, pp. 687-692Mandelberg, A., Tal, G., Naugolny, L., Cesar, K., Oron, A., Houri, S., Lipopolysaccharide hyporesponsiveness as a risk factor for intensive care unit hospitalization in infants with respiratory syncitial virus bronchiolitis (2006) Clin Exp Immunol, 144, pp. 48-52Puthothu, B., Forster, J., Heinzmann, A., Krueger, M., TLR-4 and CD14 polymorphisms in respiratory syncytial virus associated disease (2006) Dis Markers, 22, pp. 303-308Mailaparambil, B., Krueger, M., Heinze, J., Forster, J., Heinzmann, A., Polymorphisms of toll like receptors in the genetics of severe RSV associated diseases (2008) Dis Markers, 25, pp. 59-65Amanatidou, V., Sourvinos, G., Apostolakis, S., Neonaki, P., Tsilimigaki, A., Krambovitis, E., RANTES promoter gene polymorphisms and susceptibility to severe respiratory syncytial virus-induced bronchiolitis (2008) Pediatr Infect Dis J, 27, pp. 38-42Kresfelder, T.L., Janssen, R., Bont, L., Venter, M., Confirmation of an association between single nucleotide polymorphisms in the VDR gene with respiratory syncytial virus related disease in South African children (2011) J Med Virol, 83, pp. 1834-1840Janssen, R., Bont, L., Siezen, C.L., Hodemaekers, H.M., Ermers, M.J., Doornbos, G., Genetic susceptibility to respiratory syncytial virus bronchiolitis is predominantly associated with innate immune genes (2007) J Infect Dis, 196, pp. 826-834Amanatidou, V., Sourvinos, G., Apostolakis, S., Tsilimigaki, A., Spandidos, D.A., T280 M variation of the CX3C receptor gene is associated with increased risk for severe respiratory syncytial virus bronchiolitis (2006) Pediatr Infect Dis J, 25, pp. 410-414Ampuero, S., Luchsinger, V., Tapia, L., Palomino, M.A., Larrañaga, C.E., SP-A1, SP-A2 and SP-D gene polymorphisms in severe acute respiratory syncytial infection in Chilean infants (2011) Infect Genet Evol, 11, pp. 1368-1377Mulet, J.F., Rodríguez De Torres, B.O., Viral induced bronchiolitis and genetics (2010) An Pediatr (Barc), 73, pp. 159-16

    Spin Glass Behavior in RuSr2Gd1.5Ce0.5Cu2O10

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    The dynamics of the magnetic properties of polycrystalline RuSr2Gd1.5Ce0.5Cu2O10 (Ru-1222) have been studied by ac susceptibility and dc magnetization measurements, including relaxation and ageing studies. Ru-1222 is a reported magneto-superconductor with Ru spins magnetic ordering at temperatures near 100 K and superconductivity in Cu-O2 planes below Tc ~ 40 K. The exact nature of Ru spins magnetic ordering is still debated and no conclusion has been reached yet. In this work, a frequency-dependent cusp was observed in ac susceptibility vs. T measurements, which is interpreted as a spin glass transition. The change in the cusp position with frequency follows the Vogel-Fulcher law, which is commonly accepted to describe a spin glass with magnetically interacting clusters. Such interpretation is supported by themoremanaent magnetization (TRM) measurements at T = 60 K. TRM relaxations are well described by a stretched exponential relation, and present significant ageing effects.Comment: 4 pages, 6 figures, submitted to Phys. Rev.

    About Bianchi I with VSL

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    In this paper we study how to attack, through different techniques, a perfect fluid Bianchi I model with variable G,c and Lambda, but taking into account the effects of a cc-variable into the curvature tensor. We study the model under the assumption,div(T)=0. These tactics are: Lie groups method (LM), imposing a particular symmetry, self-similarity (SS), matter collineations (MC) and kinematical self-similarity (KSS). We compare both tactics since they are quite similar (symmetry principles). We arrive to the conclusion that the LM is too restrictive and brings us to get only the flat FRW solution. The SS, MC and KSS approaches bring us to obtain all the quantities depending on \int c(t)dt. Therefore, in order to study their behavior we impose some physical restrictions like for example the condition q<0 (accelerating universe). In this way we find that cc is a growing time function and Lambda is a decreasing time function whose sing depends on the equation of state, w, while the exponents of the scale factor must satisfy the conditions i=13αi=1\sum_{i=1}^{3}\alpha_{i}=1 and i=13αi2<1,\sum_{i=1}^{3}\alpha_{i}^{2}<1, ω\forall\omega, i.e. for all equation of state,, relaxing in this way the Kasner conditions. The behavior of GG depends on two parameters, the equation of state ω\omega and ϵ,\epsilon, a parameter that controls the behavior of c(t),c(t), therefore GG may be growing or decreasing.We also show that through the Lie method, there is no difference between to study the field equations under the assumption of a cc-var affecting to the curvature tensor which the other one where it is not considered such effects.Nevertheless, it is essential to consider such effects in the cases studied under the SS, MC, and KSS hypotheses.Comment: 29 pages, Revtex4, Accepted for publication in Astrophysics & Space Scienc
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