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We study anisotropic universe in the f(R, T) modified theories of gravity in the presence of a simplest non-minimal coupling between matter and geometry. We obtain the cosmological implications of this model, as well as the equations of state and the deceleration parameters, which follow from the covariant divergence of the stress-energy tensor. We discuss energy conditions in f(R, T) gravity for an anisotropic universe with an effective matter energy-momentum tensor. It is found that the energy conditions are satisfied for the parameter range considered. We also do a numerical calculation of the model to investigate the behavior of the anisotropy on the evolution of the universe in the f(R, T) cosmology. We find out that the anisotropy can decrease to the order O([10.sup.-5]) at the present time. Key words: anisotropic universe, f(R, T) gravity, energy conditions, nonminimal matter-geometry coupling, Bianchi type I. Nous etudions un univers anisotrope dans des theories modifiees f(R, T) de la gravite, en presence du plus simple couplage non minimal entre matiere et geometrie. Nous determinons les implications cosmologiques de ce modele, ainsi que les equations d'etat et les parametres de deceleration qui decoulent de la divergence covariante du tenseur d'energie- impulsion. Nous discutons les conditions sur l'energie en gravitef(R, T) pour un univers anisotrope avec un tenseur d'energie- impulsion de matiere effective. Nous trouvons que les conditions sur l'energie sont satisfaites pour le domaine parametrique considere. Nous completons aussi des calculs numeriques sur le modele pour examiner le comportement de l'anisotropie sur revolution de l'univers en cosmologief(R, T). Nous trouvons que l'anisotropie peut decroitre jusqu'a l'ordre O([10.sup.-5]) au temps present. [Traduit par la Redaction] Mots-cles: univers anisotrope, gravite f (R, T), conditions sur l'energie, couplage matiere-geometrie non minimal, type I de Bianchi., 1. Introduction According to cosmological observations, it can be claimed that the present observable universe is undergoing accelerating expansion [1, 2]. In such a way, these observations are based on [...]

In this work, we regard f(R, T) gravity as an effective description of the acceleration of the universe and reconstruct the functionf(R, T) from the holographic Ricci dark energy by considering a Bianchi type I universe. So the connection gives us an opportunity to redefine the Hubble parameter, the pressure, the equations of state parameter, and the energy density parameter representation by considering Bianchi type I models for holographic Ricci dark energy. We wrap up the evolution of the accelerated expansion of the anisotropic universe, which is faster than the evolution of the FRW and ACDM models. Key words: anisotropic universe, modified gravity, holographic Ricci dark energy, Hubble parameter, Bianchi type I. Nous considerons ici la gravitef(T, R) comme une description efficace pour l'acceleration de l'univers et reconstruisons la fonction f(T, R) a partir de l'energie sombre holographique de Ricci en considerant un univers de type I de Bianchi. Cette connexion nous donne alors une opportunite pour redefinir le parametre de Hubble, la pression, l'equation du parametre d'etat et la representation du parametre de densite d'energie en considerant des modeles de type I de Bianchi pour l'energie sombre holographique de Ricci. Nous concluons avec une evolution de l'expansion acceleree de l'univers anisotrope qui est plus rapide que l'evolution des modeles FRW et ECMD. [Traduit par la Redaction] Mots-cles : univers anisotrope, gravite modifiee, energie sombre holographique de Ricci, parametre de Hubble, type I de Bianchi., 1. Introduction Type Ia supernovae observational data show that the universe is dominated by two dark components: dark matter (DM) and dark energy (DE) [1, 2]. DM, matter without pressure, [...]

"nBackground and Aims: Candida species are opportunistic pathogens which live as benign commensal organisms in the oral cavities. The infants are more susceptible to opportunistic microorganism colonization. This study was design to evaluate the presence and quantity of Candida colonies in infants' oral cavities and its relation with age, gender, and type of diet and mothers' education level."nMaterials and Methods: This historical cohort study was performed on two groups of infants; 1) infants predominantly on breastfeeding (n=45) and 2) infants on bottle feeding (n=45). Oral samples were collected with swab technique and Candida species were identified using germ-tube test. The data were analyzed by using SPSS software, chi-square, logistic regression and Mann-Whitney tests."nResult: The Candida colony was seen in 53.3% of infants. The difference in oral Candida carriage and mean numbers of Candida colonies, according to the mothers' education level, was statistically significant (P=0.0001, P=0.000, P=0.0001); however, the mentioned two groups were not significantly different in terms of the presence of Candida and non Candida species (P=0.45). Candida colonization was not statistically related to the age and sex (P=0.48, P=0.4). By logistic regression test, it was found that type of diet and mother's education level affected oral Candida colonization (P

Antibiotic contamination of aqueous environment due to pharmaceutical sewage may lead to development of antibiotic-resistant bacteria strain. In this research, elimination of antibiotics from synthetic wastewater was investigated. For this purpose, sulfamethoxazole and trimethoprim were treated by a pilot scale of net-like rotating biological contactor with three compartments, 48 plastic discs with total volume of 78.75 L. This system was continuously operated for about one year at various organic loading rates with different antibiotic dosages. The obtained results indicated that by increasing hydraulic retention time, the chemical oxygen demand (COD) removal was gradually increased. The optimal hydraulic retention time for desired rate of COD removal was 36 h. In addition, the effect of hydraulic retention time, organic load rate and sulfamethoxazole concentration in the removal of sulfamethoxazole and organic matter was assessed. Moreover, the results demonstrated that with increasing in organic load rate, sulfamethoxazole elimination was enhanced. In the next step, simultaneous removal of both antibiotics for constant inlet COD concentration of 8000 mg/L at optimum hydraulic retention time was analysed. The results showed that trimethoprim removal efficiency was approximately 100%, even at high concentration of trimethoprim (50 mg/L). For observation of dominant microorganism, samples of the developed biofilm on rotating biological contactor discs were scanned by scanning electron microscopy. In the first compartment where biomass was exposed to highest concentration of antibiotics, fungus strains were the dominant organism. In the second and third compartment antibiotic-resistant bacteria were the dominant attached living organisms. [ABSTRACT FROM AUTHOR]

The paper deals with a spatially homogeneous and anisotropic universe filled with perfect fluid and dark energy components. We consider the f( R, T) theory according to holographic and new agegraphic dark energy in the Bianchi type I universe. In this study, we concentrate on two particular models of f( R, T) gravity namely, R+2 f( T) and f( R)+ λT. We conclude that the derived f( R, T) models can represent phantom or quintessence regimes of the universe. [ABSTRACT FROM AUTHOR]

In this paper, we search the existence of Bianchi type I cosmological model in f( R, T) gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar R and of the trace of the stress-energy tensor T. We obtain the gravitational field equations in the metric formalism, and reconstruct the corresponding f( R, T) functions. Attention is attached to the special case, f( R, T)= f( R)+ f( T) and two examples are assumed for this model. In the first example, we consider the unification of matter dominated and accelerated phases with f( R) gravity in anisotropic universe, and in the second instance, model of f( R, T) gravity with transition of matter dominated phase to the acceleration phase is obtained. In both cases, f( R, T) is proportional to a power of R with exponents depending on the input parameters. [ABSTRACT FROM AUTHOR]

It is shown that the acceleration of the universe can be understood by considering a f( T) gravity models. Modified teleparallel gravity theory with the torsion scalar has recently gained a lot of attention as a possible explanation of dark energy. For these f( T) gravity models, a variant of the accelerating cosmology reconstruction program is developed. We consider spatially homogenous and anisotropic Bianchi type I universe in the context of f( T) gravity. The de Sitter, power-law and general exponential solutions are assumed for the scale factor in each spatial direction and the corresponding cosmological models are reconstructed. We reconstruct f( T) theories from two different holographic dark energy models in different time durations. For the holographic dark energy model, the dark energy dominated era with new setting up is chosen for reconstruction, and the Ricci dark energy model, radiation, matter and dark energy dominated time durations are all investigated. Finally we have obtained a modified gravity action consistent with the holographic dark energy scenario. [ABSTRACT FROM AUTHOR]

As one of the basic human needs, housing directly affects the quality of peoples' life and is considered to be one of the main concerns of most families. Therefore, provision of suitable housing for citizens is one of the main objectives of economic development plans in many countries. It is important to note that the majority of housing policies have focused mainly on urban housing and despite the fact that an important part of the rural population, especially in developing countries, lives in inadequate housing in terms of physical conditions, little attention is paid on them by governments and other official institutions. The main purpose of this article is to examine the role of Iran's new housing policy on the quality of housing constructions in rural areas. Given the fact that following the provision of low-interest rural housing loan since 2006, a considerable number of housing has been constructed in rural areas, assessing the effects of this policy can be important. In this study, villages in the Shaft District of Guilan province in the north of Iran have been selected as a case study. The data utilized in this study comes from a questionnaire survey through which 332 loan receiving families were studied. Statistical methods including T-test were used to analyze the collected data. The main findings of the study indicate a significant improvement in the physical structure, main building material and building facade of the newly built houses in rural areas. The newly constructed houses also reflect the changes in rural lifestyle in their physical patterns such as smaller size, fewer rooms and low rate of household per housing unit in comparison with the old houses. However, for the facilities, except the telephone rate, no significant difference is observed between the old and new housing units. [ABSTRACT FROM AUTHOR]

Objective: Although cost-effectiveness analyses (CEAs) have been advocated as a tool to critically appraise the value of health expenditures, it has been widely hoped that they might also help contain health care costs. To determine how often they discourage additional expenditures, we reviewed the conclusions of recently published CEAs.Data Sources: A search of the Abridged Index Medicus (a subset of MEDLINE designed to afford rapid access to the literature of "immediate interest" to the practicing physician) between 1990 and 1996.Study Selection: We only included articles that reported an explicit cost-effectiveness (CE) ratio (a cost for some given health effect) in the abstract.Data Abstraction: From each abstract, we collected the value for the incremental CE ratio and the measure of health effect (life-years, quality-adjusted life-years [QALYs], other). We then categorized the authors' conclusion into one of three categories: supports strategy requiring additional expenditure, no firm conclusion, and supports low-cost alternative. Finally, we obtained the article and collected information on funding source.Data Synthesis: Among the 109 eligible articles, the authors' conclusion supported strategies requiring additional expenditure in 58 (53%) and supported the low-cost alternative in 28 (26%). We then focused on the 65 articles reporting either life-years or QALYs. Cost-effectiveness ratios ranged from $400 to $166,000 (per life-year or QALY) in the 39 articles (60%) in which authors supported additional expenditure, and ranged from $61,500 to $11,600,000 in the 13 articles (20%) in which authors supported the low-cost alternative. Despite identifying similar CE ratios, authors arrived at different conclusions in the overlapping range ($61,500 to $166,000). Of the 10 articles acknowledging industry funding, 9 supported a strategy requiring additional expenditure (p = .01 as compared with those without such funding).Conclusions: Authors of CEAs are more likely to support strategies requiring additional expenditure than the low-cost alternative. There is no obvious consensus about how small the CE ratio should be to warrant additional expenditure. Finally, concerns about funding source seem to be warranted. [ABSTRACT FROM AUTHOR]