1,645 research outputs found
Is opioid dependency related to coping strategies?
Using opioid for recreational purposes has a very long history in Iran. Social influence is a useful framework in understanding how the social environment affects the individual's behavioral choices to use drugs. We compared opioid dependents (n=149) with controls (n=221) on measures of coping strategies using the Jalowiec Coping Scale and some socioeconomic factors. The differences in 10 of 15 coping strategies were significant in the study groups (P<0.05). Although, the combined score of problem-oriented and affective-oriented items did not show any significant difference between the two groups. There was a significant relation between opioid dependence with smoking cigarettes (P<0.001), lower education (P=0.002), being employed (P<0.001), having children (P<0.001), and being married (P<0.001). Educational programs to improve problem solving and coping skills can be helpful to reduce the rate of dependency to opioid and smoking cigarettes. © 2015, Sadeghali Taziki, et al
Efficient adaptive integration of functions with sharp gradients and cusps in n-dimensional parallelepipeds
In this paper, we study the efficient numerical integration of functions with
sharp gradients and cusps. An adaptive integration algorithm is presented that
systematically improves the accuracy of the integration of a set of functions.
The algorithm is based on a divide and conquer strategy and is independent of
the location of the sharp gradient or cusp. The error analysis reveals that for
a function (derivative-discontinuity at a point), a rate of convergence
of is obtained in . Two applications of the adaptive integration
scheme are studied. First, we use the adaptive quadratures for the integration
of the regularized Heaviside function---a strongly localized function that is
used for modeling sharp gradients. Then, the adaptive quadratures are employed
in the enriched finite element solution of the all-electron Coulomb problem in
crystalline diamond. The source term and enrichment functions of this problem
have sharp gradients and cusps at the nuclei. We show that the optimal rate of
convergence is obtained with only a marginal increase in the number of
integration points with respect to the pure finite element solution with the
same number of elements. The adaptive integration scheme is simple, robust, and
directly applicable to any generalized finite element method employing
enrichments with sharp local variations or cusps in -dimensional
parallelepiped elements.Comment: 22 page
Generalized Duffy transformation for integrating vertex singularities
For an integrand with a 1/r vertex singularity, the Duffy transformation from a triangle (pyramid) to a square (cube) provides an accurate and efficient technique to evaluate the integral. In this paper, we generalize the Duffy transformation to power singularities of the form p(x)/r
α
, where p is a trivariate polynomial and α > 0 is the strength of the singularity. We use the map (u, v, w) → (x, y, z) : x = u
β
, y = x
v, z = x
w, and judiciously choose β to accurately estimate the integral. For α = 1, the Duffy transformation (β = 1) is optimal, whereas if α ≠1, we show that there are other values of β that prove to be substantially better. Numerical tests in two and three dimensions are presented that reveal the improved accuracy of the new transformation. Higher-order partition of unity finite element solutions for the Laplace equation with a derivative singularity at a re-entrant corner are presented to demonstrate the benefits of using the generalized Duffy transformation
Purification and characterization of α-galactosidase from Lactobacillus acidofillus
α−Galactosidase (α-D-galactoside galactohydrolase [EC 3.2.1.22]) was obtained from Lactobacillus acidofillus which was grown in modified de Man, Rogosa and Sharpe (MRS) medium, supplemented with raffinose. α-Galactosidase was released from the cells by ultrasonic treatment, then precipitated by ammonium-sulfate and further purified with Sephadex G-200 and DEAE cellulose chromatography with a 18.5-fold increase in specific activity and 28% recovery. Km and Vmax for this enzyme was determined by p-nitrophenyl-α-D-galactoside as substrate, to be about 0.47 mM, and 17.54 μmol/min per mg of protein, respectively. Maximum enzymatic activity occurred at pH 5.5 and temperature at 45°C. The enzymatic activity was retained at least for 30 min, at temperatures of 25 - 55°C, but there was inactive temperature at about 60°C. Galactose was able to decrease the enzyme activity by a factor of 63%. Among the sugars tested, fructose, glucose, sucrose, lactose and mannose reduced the enzyme activity only slightly (less than 10% of the control). A strong inhibition of α-galactosidase activity was found in the presence of 0.1 mM HgCl.Key words: α-Galactosidase, enzyme purification, Lactobacillus acidofillus, kinetic studies
Effects of dietary physical form and dietary inclusion of probiotic and enzyme on growth performance, cellular and humoral immunity, and relative weights of lymphoid organs at early period of broiler chickens fed triticale-based diets
The aim of the present study was to investigate interactions between feed form and dietary inclusion of probiotics (live organisms) and enzymes on growth performance, cellular and humoral immunity, and relative weights of lymphoid organs of broiler chicks fed a triticale-based diet. A total of 640 broiler chicks were allocated to eight treatments when they were one day old, with four replicates (n = 20 chicks in each). The dietary treatments consisted of feed form (pellets or mash) and dietary supplementation with or without a Bacillus-based probiotic (0.03% diet) and enzyme (carbohydrase, 0.05% diet) in a 2 × 2 × 2 factorial arrangement. Feed conversion ratio (FCR) was calculated based on feed intake (FI) and weight gain (WG). The WG of the broiler chicks fed the pelleted diets containing the enzyme and probiotic (alone or in combination) was greater than that of the birds fed the mash diets without these additives. Significant interaction effects of the enzyme and probiotic on FCR and FI were observed in the starter period. The heterophil : lymphocyte (H : L) ratio of the chicks fed the pelleted diet containing the enzyme and probiotic was lower than that of the birds fed the other diets. The cellular immunity of the birds fed this diet increased after 24 hours, as shown by the results of a challenge experiment with dinitrochlorobenzene (DNCB) or an injection of phytohemagglutinin (PHA). In conclusion, feed form and supplementation of a triticale-based diet with feed enzymes and probiotics can greatly improve the growth performance and immunity of broiler chicks. Keywords: Dinitrochlorobenzene, Di-Pro probiotic, phytohemagglutinin, Rovabio enzyme, spleen, viscosit
The effect of metformin on biomarkers associated with breast cancer outcomes: a systematic review, meta-analysis, and dose–response of randomized clinical trials
Numerical Evaluation the Impact of the Inserts Shape on Thermo-Flow Behavior in a Heat Exchanger
The improvement of transfers in a heat exchanger can be achieved either by increasing its coolant thermal conductivity or by modifying its geometrical configuration. In this paper, we will be interested in the latter technique by choosing a three-dimensional configuration represented by a channel of rectangular section, on which solid fins of square, circular, or diamond section (vortex generator) have been transversally mounted, which are moreover adiabatic and non-rotating. A convective and forced airflow traverses the channel, and the study focused in principle on the effects of the shape of the fins on the structure of the flow and the rate of heat transfer. The problem is governed by the Navier-Stokes system, coupled with the energy equation de-scribing the thermal process. The resolution of the equation system governing the hydrodynamic phenomenon is performed numerically in three dimensions. To do this, the governing equations of the thermo-hydrodynamic phenomenon are discretized by a finite volume scheme. As for turbulence, it is modeled using the standard model k-É›, and the problem of pressure-velocity coupling is solved by the SIMPLE algorithm (Semi Implicit Method for Pressure Linked Equation). The computed results are presented as curves for the Nusselt number, friction factor, thermal enhancement factor, or amount of heat dissipated, and as a map for the contour of the axial velocity norm and the temperature field distribution
Life Cycle Assessment of Municipal Waste Management System (Case Study: Karaj, Iran)
LCA has been defined as a tool for evaluating the environmental burdens and potential impacts that can be applied to municipal solid waste management systems for determine the optimum municipal solid waste (MSW) management strategy.To investigate the Waste Management system strategyof Karaj City we used LCA method. Three scenarios were defined and compared based on environmental burden include water pollution, air pollution, consumed energy and waste residues.. For each of these scenarios, an ecological indicator was achieved from checklist values. From the environmental point of view, results show that recycling is one of the best alternatives for Waste Management. Furthermore, composting has an important role in alleviating the load of pollutants and energy usage in the Waste Management system. ©JASEMKeywords: Waste Management system, LCA, Kara
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