BIOLOGICAL SCIENCES (DANISH-I ZISTI-I IRAN)
Year:2009 | Volume:4 | Issue:2|Papers Count:8

During 2006-2007 a faunistic survey was carried out to study the edaphic oribatid mites in Sorkhe-Hesar forest park of Tehran. A Total of 10 species from 7 genera and 7 families were collected and identified. Identifications were confirmed by Louice Quetzee and Lizel Hugo (Dept. Acarology, National museum, Bloemfotein, South Africa) and specimens were deposited at the Acarology collection of the Entomology Department, Islamic Azad University, Science and Research Branch. They are listed below; five species which are marked by asterisks are considered to be new records for Iran.Galumnoidea                 Galumnidae                   Galumna discifera Balogh, 1960                                                                        Galumna dimidiata Engelbrecht, 1969Oripodoidea                   Oribatulidae                   Oribatula tibialis Nicolet, 1855                                                                        Oribatula connexa Berlese, 1904                                    Protoribatidae                Protoribates paracapucinus Mahunka, 1988                                                                        Protoribates maximus Mahunka, 1988Epilohmannioidea           Epilohmanniidae Epilohmannia cylindrical Berlese, 1904Tectocepheoidea            Tectocepheidae  Tectocepheus minor Berlese, 1903Microzetoidea                Microzetidae                  Berlezetes ornatissimus Berlese, 1913Gymnodamaeoidea        Gymnodamaeidae          Jacotella glaber Miheleie, 1957

Since hundreds of years ago, researchers have been studying the accumulation of metals in aquatic organisms` tissues and their effects on ecosystem. But in some decades before, relationship between enzymes to heavy metals has made researchers become interested in this field. Some organic and inorganic pollutions cause Oxidative stresses in marine organisms. Due to these problems bio-indicators such as mussels, barnacles and fishes can help to recognize polluted areas and the scale of polluted materials in marine organism’s tissues as a useful tool. On the other hand, in oil platforms there are heavy metals due to discharge of hydro-carbonated material and this tissue is a suitable area for assaying of relationship between heavy metals and enzymes. Accordingly, changes in superoxide dismutase enzyme in barnacle were chosen as a biomarker. For assaying of Nickel, Cobalt and Vanadium in seawater, tissue was gathered from eight stations of Bahragan area. The average amount of these metals within samples taken from barnacles was 0.4 ppm (Ni), 0.2 ppm (Co), and 0.2 ppm (V). Also analyses were assayed by Atomic Absorption. Correlation coefficient for Vanadium, Nickel and Cobalt in water samples were respectively 0.43, 0.50 and 0.56 and also in tissue -0.19,-0.15, -0.16 that assay by special kit. The only positive correlation was found between TDS and superoxide dismutase (r=0.775), while other parameters showed insignificant correlation.

Nowadays, because of using chemical pesticides and their harmful effects on human health and environment, scientists and researchers have noticed the use of biological controls. One of the most important micro-organisms in this regards is Bacillus thuringiensis. In this research, we have isolated 50 strains from the soil of Khorasan and Hamedan provinces. Characterization of these strains was based on PCR analysis using 14 specific primers for cry1a, cry1b, cry1c, cry1d, cry1e, cry1f and cry1g genes encoding proteins active against Lepidopteran. Analysis of PCR products by using agarose gel electrophoresis and comparing them with standard strains showed that the abundance of these genes in the strains, is very different. Some strains have a variety of genes while the other have only one or have none. These results are important to explore future microbial strategies for the control of these crop pests in Iran.

Shesh Rodbar reserve area is located in the northwest of Savadkoh country. The regional climate is cold mountainous. This region is located between longitudes 35° 59’ to 36° 56’ N and latitudes 53° 47’ to 53° 59’ E. Its maximum altitude is 2453 m. The precipitation in this region is about 733.5 mm. The plants specimens were collected between 2007 and 2008. The specimens are preserves in Mahmodieah Center’s Herbarium. About 278 species belong to 200 genera and 67 families. The most abundant families are Asteraceae, Lamiaceae, Poaceae, Rosaceae, Brassicaceae and Fabaceae. 41.72 percent of species are hemicrypthophytes. 31.65% (88 species) of species are Irano–Turanian, Euro-Sieberian. According to the obtained results from the plant species in this study, ecological factors such as altitude, slope, and exposure and wind direction are important factors on plants distribution.

Research in biology is usually thought to be based on experimentation with materials, while in mathematical biology experimentation is of a theoretical nature. A major advantage of applying mathematics to biological systems is the ability to construct mathematical models. Such models are mathematical systems that attempt to represent the complex interactions of biological systems in a way simple enough for their properties to be understood. In fact, mathematics can be applied to most areas of biology. Counting the number of RNA structures is an combinatorial method in biomathematics. In this paper, RNA structures are modeling as graphs. We consider 2 parameters on this model. One of them is the length of arc, where arc correspond to hydrogen bond and between two nucleotides. Another one is the number of mutually crossing arcs, where cross of arcs correspond to existence of pseudoknot in RNA structure. Now, we categorize RNA structures according to these 2 parameters and enumerate them.

Although several plants and procedures for treatment of kidney stone disease in Iranian folk medicine, urolithiasis has been an important problem for patients, yet. Aim of present study, investigation of effect of Zea mays L. corn silk hydro-alcoholic extract on calcium oxalate crystallization was studied in male rats. At first, hydro-alcoholic extract of plant at doses of 100, 200 and 300 mg/kg were prepared. Crystallization of calcium oxalate was induced by adding ammonium chloride and ethylene glycol in drinking water for 3 and 32 days, respectively. Control group was treated by drinking water. Experimental groups were treated by extract at doses 100, 200 and 300 mg/kg orally for 35 days. After 35 days, animals were anesthetized by ether and right kidneys removed and put them in buffered formaldehyde. Specimens were prepared for histological studies and stained by H&E. Results showed that treatment of extract decreased number of crystals in kidney of experimental animals in comparison with control groups. So, it could prevent formation of kidney stone primary nucleus.

Tajan River is one of the significant rivers of Caspian Sea which is originated in Alborz mountains and This study was carried out in Tajan river from March 2007 to February 2008. Samples were taken from amongst stones in monthly interval periods. Samples were immediately fixed with formaldehyde 4% insitu. For exact recognition, permanent mounts were prepared by using Patrick & Reimer procedure. Identification of diatoms was done by means of light microscope and specialized recognition keys. For study of diatom communities in aquatic ecosystems, counting method is used because in this method, identification and determination of diatom communities and morphological variations of species are better known. Water temperature, pH, EC, DO, TDS, BOD, COD, PO43-, NO3-, SiO2, Na+, Ca2+, SO42-, K+, Mg2+, Clˉ and Nh4+ were analysed during the study. In this research 95 species and 23 genera of epilithic diatoms were identified. Epilithic diatoms have been recommended by researchers from several countries as particullary suitable for water quality evaluation. Multivariate analyses of species composition data were applied in two different approaches. Firstly, species and sampling stations were grouped using TWINSPAN (Two Way Indicator Species Analysis). Secondly, Canonical Correspondence Analysis (CCA) was applied in order to uncover the main gradients of changes in species composition relating this change   to the pollution.

Cupper is one of the essential micronutrients for the normal growth and development of plants. It is also known that a heavy metal at higher level causes toxicity in most plants. This research investigated the effects of CuSo­4 toxicity on growth and tolerance of sunflower cultivar Hi sun-33. The experiment was carried out under hydroponic conditions with 5 treatments (0, 25, 50, 75 and 100mM) and 4 replicates for 21days. The dry weight of roots and shoots, chlorophylls a and b, carotenoids in leaves, soluble sugars and starch in roots and shoots, MDA content and enzyme activity of peroxidase in leaves, Cu accumulation in roots and shoots were measured. The results obtained from the analyzing of Cu content in the roots and shoots of different treatments indicated that Cu absorption goes up by increasing level of Cu in growth solution and Cu accumulates in the roots and its transport to the shoots is low. The dry weight of roots significantly decreased in comparison to control by increasing Cu concentration. The reduction of dry weight of shoots in treatments of 75 and 100mM were significant. The decrease of chlorophylls a and b in leaves, except in treatment of 25mM was significant in comparison to control. The carotenoids content significantly decreased in treatments of 75 and 100mM Cu. Determination of the amount of soluble sugars indicated that the soluble sugars of roots and shoots increased significantly by increase in Cu, but starch levels were decreased in both. The MAD content in leaves significantly increased with increasing of Cu toxicity. The increase of peroxidase activity in leaves, except for treatment of 25mM was significant by increasing the level of Cu in growth solution. The Cu tolerance is associated with the Cu accumulation in roots, increase of soluble sugars and activation of antioxidant defense system.