Journal of Sciences, Islamic Republic of Iran
Year:2013 | Volume:24 | Issue:4|Papers Count:9

Development of an environmental friendly and cost-effective process for microbial degradation of caffeine to non-toxic compounds are promising to solve the problems of physiochemical extraction of caffeine in the treatment the caffeine containing agro-industrial effluents. Thirteen bacterial strains, isolated from tea plantation soils in the north region of Iran, were screened to show their abilities in using caffeine as the sole source of carbon and nitrogen. The intrinsic tolerance of the isolated strains to the caffeine substrate was measured in a defined and complex medium by using the agar dilution method. Based on the tolerance efficiency, isolate TPS8 which showed maximum tolerance to caffeine was selected and identified as Pseudomonas pseudoalcaligenes strain TPS8 (GenBank accession number KF414528) according to the cultural and physiochemical characteristics and also 16S rDNA gene sequencing. Growing cells of P. pseudoalcaligenes TPS8 were used for the biodecaffeination experiments. The maximum removal of caffeine (80.2%) was reached after a 72 h incubation using 2.5 g/l of caffeine substrate without further optimization. Our results show that growing cells of P. pseudoalcaligenease TPS8 can thus be efficiently used as a simple and cheap process for preparative decaffeination from agro-industrial effluents. The present survey is the first report on biodecaffeination using Pseudomonas pseudoalcaligenes.

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Chromosomal patterns of experimental animals are useful tools for cytogenetics research and animal breeding. Chromosome investigations of the hairless guinea pig are rare, therefore, karyotype of hairless guinea pigs (twelve male and female) was studied using metaphase spreads of bone marrows and G banding techniques. The chromosomes diploid number was 2n=64 and polymorphism of three type chromosomal pairs were observed in the genus Cavia of Iranian hairless guinea pigs. A karyotype of 24 biarmed pairs and seven pairs of acrocentric chromosomes, 2 of sex chromosomes were also seen. The findings describe the karyology of the hairless guinea pig that is produced by Razi vaccine and serum research institute of Iran that improves our knowledge about laboratory hairless guinea pig and provides basic data for further use of the animal.

Formation of non bonded organic layer around inorganic particles like iron sulfide and zeolites, was hypothesized as starting point for one of the possible mechanisms of the origin of life on earth. In this study, the general circumstances needed for creation of such organic layer was investigated. An aliphatic hydrocarbon (hexane), an aromatic hydrocarbon (toluene), an alcohol (n-octanol) and an amino acid (phenylalanine) were used for simulation of the primordial soup. FeS, montmorillonite and clinoptilolite were used as insoluble inorganic particles. Non-bonded organic layer can be formed in both fresh and saline waters. Formation of organic layer is a pH sensitive process and the best pH for formation of this layer is around 6 (similar to the pH of primordial oceans of the earth). Low concentration of water in organic layer causes the less degradation rate of the polymers and various organic molecules and thus increases their stability.

Abderaz The composition of the essential oil obtained from the seeds of Ammi majus L. which collected from province of Khozestan in the southwest area of Iran.The oils was analyzed by gas chromatography mass spectrometry (GC-MS). Twenty - eight components have been identified in the extract of A. majus L. with Toluene (3.766%), Thymol (12.811%), Carvacrol (37.811%) as major components, respectively. The seeds extract was rich in monoterpenes. The various functions of terpenoide compounds have been widely studied. They have diverse activity including antibacterial, antifungal, antinociceptive, anti-inflammatory relieving digestive and anticancer.

In this study, concentrations of heavy metals in soils around a Zn-smelter in Qeshm island, Iran, are investigated. Calculated geoaccumulation index (Igeo), contamination factor (Cf), and contamination degree (Cdeg) values indicate surface soil contamination by toxic metals (As, Cd, Pb, and Zn). The results also indicate that most contaminated areas are located in the vicinity of the smelter and waste pile. However, concentrations of soil metals decrease with increasing distance from the pollution sources. Results from a potential ecological risk assessment indicate high risk in areas around the smelter. Statistical analysis also confirms the role of the Zn-smelter in soil contamination in the study area.

A modified F-expansion method to find the exact traveling wave solutions of two-component nonlinear partial differential equations (NLPDEs) is discussed. We use this method to construct many new solutions to the nonlinear Whitham-Broer-Kaup system (1+1)-dimensional. The solutions obtained include Jacobi elliptic periodic wave solutions which exactly degenerate to the soliton solutions, triangular periodic wave solutions, exponential solutions and rational solutions under certain limitet conditions. In addition, some figures of partial solutions are provided for direct-viewing analysis. The method can also be extended to other types of nonlinear evolution equations in mathematical physics.

In this paper, an algorithm, based on genetics and auxiliary nodes, to reduce energy consumption in wireless sensor networks has been presented. In this research, by considering some parameters as energy and distance, a target function has been created, which is more optimum comparing to other methods. In this research cluster head is selected by genetic algorithm. In RAWSN algorithm a new technique of replacing auxiliary nodes when some CHs energies come to an end, is presented. The results of simulation show that the number of alive nodes at the end of each round increases comparing to other methods and this has led to prolongation of network lifetime.

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