IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY TRANSACTION A- SCIENCE
Year:2007 | Volume:31 | Issue:A1|Papers Count:17

It has been well established that the secretions of thyroid hormones and growth hormone (GH) is under the regulation of different neurotransmitters. The goal of this study was to determine whether substance-P, as a neurotransmitter, regulates the mean plasma concentrations of thyroxin (T4), triiodothyronine (T3), GH, milk amount and constituents in Sanan goats. Nine Sanan goats were randomly divided into 3 groups. Each group received a daily infusion of either 1, 2 or 4 Ug substance-P for 7 days into the third ventricle. Blood samples were collected daily for 11 days, and assayed for plasma T3, T4 and GH concentrations by double-antibody RIA. Milk samples were collected daily for each of the 11 days. Milk samples were assayed for protein, fat and lactose constituents. The daily amount of milk was determined throughout the experiment. Infusions of 1 and 2 Ug substance-P did not change the plasma concentrations of the T3, T4 and GH throughout the experiment. Infusions of 4 Ug substance-P significantly (P<0.01) increased the plasma concentrations of the T3, T4 and GH among all the animals, however, different dosages of substance-P did not change the amount, the protein, fat and lactose constituents of milk among all the animals in the different groups. The result of this experiment indicated that substance-P may increase the mean plasma concentrations of GH, T3, and T4 in Sanan goats.

In recent decades, the discharge of industrial wastewater from different resources containing heavy metals has resulted in a population increase of the resistant bacteria. This problem is considerably more common in industrial areas in which the discharge of wastewater containing heavy metals into rivers has caused the heavy metals to be sorbed by soil particles (especially clay) and transfer far distances from the discharging point. The results of some studies show that, in the Zayanderood river, the concentration of heavy metals in less settlable particles such as clay, which can travel far distances down the river, is significantly higher in lower parts of the river than the upper parts. This condition shows that, there is a direct relation between the discharge of wastewater in this river and the pollution of river sediments [1, 2]. In addition, the findings of some other researchers in other parts of Iran also indicate that the rate of metal exhibition concentration (As, Ni, Cu,…) exceeds the quality guidelines for the concentration of heavy metals in sediments [3]. Since soil is one of the most important environments for microbes and is easily exposed to many pollutants, evaluating the effects of pollutants on the microbial population is very valuable. Since the resistance of bacteria depends not only on their type and environment, but also on physical factors such as the type and concentration of the substances, the microorganisms with significant resistance can reveal the condition of their environment [4, 5].

Carbohydrates constitute a class of inexpensive natural products of high chiral content [1], and play a central role in the posttranslational biological selectivity [2]. O-Acyl-protected glycosylamines, particularly the 2, 3, 4, 6-tetra-O-pivaloyl-D-galactopyranosylamine and its acetyl derivative are effective chiral auxiliaries in the Strecker and Ugi syntheses of α-amino acids [3-5]. Glycosylamines are valuable intermediates in the preparation of nucleosides and drugs [6-8]. Carbohydrate-derived auxiliaries utilize an efficient stereoselective potential in a number of nucleophilic addition reactions on prochiral imines, a- Amino acids, and b-amino acids, and their derivatives can be synthesized in few synthetic steps with high enantiomeric purity. A variety of chiral heterocyclic can readily be obtained from glycosyl imines by stereoselective transformations [9]. The asymmetric Staudinger reaction utilizing 2, 3, 4, 6-tetra-O-acetyl- b-D-galactopyranosylamine or 2, 3, 4, 6-tetra-O-acetyl-b-D-glucopyranosylamine as the chiral auxiliary in the synthesis of 2-azetidinones has been reported by the authors [10] and others [11]. 2-Azetidinone nucleus has been recognized as the central motif of the so-called b-lactam antibiotics, the most widely employed family of antimicrobial agents to date [12]. The importance of b-lactams as synthetic intermediates has been widely recognized in organic synthesis. b-lactam molecules with a quaternary carbon center have been used as building blocks for biologically active compounds [13].

Ichnology is a field of research on biogenic structures that are preserved on the bedding planes or within the beds, and are produced by the life activity of organisms. These structures are called ichnofossils or trace fossils. Ichnologists can determine the ethology of trace fossils and distinguish ichnofacies and ichnocoenoses, though recognition of tracemakers is commonly problematic. Ichnology is very useful in studies of palaeoecology, determination of bathymetry of sedimentary basins and other palaeoenvironmental parameters [1-2]. Ichnological knowledge is based on data from the entire world. In Iran there is a great potential for ichnological studies because of the good exposure of sediments of different facies and ages. Some efforts have been made in this field in recent years [e.g. 3-5].The current study was initiated when an interesting specimen of Fustiglyphus from Upper Devonian sediments of Kuh-e Zard in the Zefreh area, northeastern Isfahan, Central Iran (Fig. 1) was sent to the author by Isfahan (Esfahan) University. The author tried but did not find additional Fustiglyphus in the field. However, other trace fossils were collected or studied there, and their taxonomic analysis is the main aim of this paper. Sampled specimens were reposited in the National Natural History Museum of Iran in Tehran (Muze-ye Melli-ye Tarikh-e Tabi’i, prefixed as MMTT) with numbers MMTT-340-347.

Foot and Mouth Disease (FMD) is the most contagious disease of cloven-hoofed animals, causing significant economical losses in livestock animals. In this study FMD Virus type A87/IRN was cultured and multiplied on BHK21 cells. The FMD virus was titrated by the Tissue Culture Infection Dose50 method (TCID50 /ml), the virus titration was 107.5. The FMD virus samples were irradiated and inactivated by gamma ray from a 60Co source at -20oC. A safety test was done by the IBRS2 monolayer cell culture method, also antigenicity of irradiated and un-irradiated virus samples was studied by Complement Fixation Test. The Dose/Survival curve for irradiated FMDV was drawn. According to the curve and D10 Value factor, the optimum dose range for the inactivation of FMDV type A87/IRN and unaltered antigenicity was obtained (40-44 kGy). The inactivated virus samples by irradiation and ethyleneimine (EI) were formulated respectively as a vaccine with Al (OH) 3 gel and other substances. The vaccines were inoculated to Guinea pigs and the results of the Sero-Neutralization Test for both the normal vaccine and radio-vaccine showed protective titre after 8 months. The potency test of the inactivated vaccines was done, Protective Dose50 Value (PD50 Value) of the vaccines were calculated to be 7.06 and 5.6 for the inactivated vaccine by EI and gamma irradiation respectively.

Glutathione S-transferase (GST) is a superfamily enzyme which plays a major role in detoxification of xenobiotic compounds by catalyzing the conjugation of xenobiotic to cellular glutathione (GSH). GST-P is an important class of GSTs which is expressed during the early stage of life and during developmental stages. Its activity is relatively high during embryogenesis and immediately after birth and diminished in normal adult rat liver. To investigate the effects of hepatotoxic agents such as acetaminophen (APAP) and aflatoxin B1 (AFB1) on liver GST-P in rats during postnatal age, suckling rats age (14±2 days old) were divided into groups (n=5) and treated with both APAP (250 or 450 mg/kg B.W) and AFB1 (3 mg/kg B.W). Livers were removed at different time intervals (2, 6, 12, 18 and 24 h) and processed for GST and GST-P activity at protein and mRNA levels (RT-PCR). Administration of a single high dose of AFB1 (3 mg/kg BW) and APAP (450 mg/kg BW) to weanling rats caused a significant (P<0.05) induction in total GST activity in developing rats. Based on the Western blotting technique and GST-P specific mRNA amplification by RT-PCR, the GST-pi protein level and its expression were not affected by APAP or AFB1. Despite the inducible effects of AFB1 and APAP on liver total GST activity, GST-P remained unaffected in response to the drugs at protein and mRNA levels.

Thirteen environmental elements were distinguished in the livers of various species of fish that have been sampled from 15 sites in a restricted area of the Khorram Abad River Basin in Lorestan province (west of Iran). Sites sampled represented agricultural, mining, mixed, and urban/recreation land uses and background conditions. Lithium and silver were not detected at any of the sites. The minimum concentration of trace elements in the fish liver of the above mentioned basin belongs to vanadium and the maximum concentration to iron. Cadmium, selenium, and zinc were selected for a more detailed analysis. Cadmium concentrations in fish liver were highest at mining land use sites, whereas the selenium and zinc concentrations were highest at agricultural land use sites in the Khorram Abad River Basin. A comparison of the study to similar studies in the United States and Iran indicated that the total medium frequency of fish samples for cadmium, selenium and zinc in the Khorram Abad unit was higher than the analyzed fish samples of the Upper Colorado River Basin and Southern beaches of the Caspian Sea study basins.

The strong ground motions recorded during the 2002 Avaj earthquake have been used to estimate S wave attenuation, Qb, and spectral decay parameter, k, for the Avaj region. Qb for shear wave is estimated as a function of frequency in the range of 0.6-18 Hz. The results show that Qb increases with frequency in the form of Qb=62.7 f0.9. Our estimates are within the estimated range for different parts of the world for QO and n. The spectral decay parameter, k, has been estimated from the high frequency of the spectra. The dependence of k on the epicenteral distance for the Avaj region is also found.

The Komshecheh barite-fluorite deposit is the product of epigenetic hydrothermal mineralization in dolomitized limestone of Middle Triassic age. The deposit is structurally and lithologically controlled and occurs predominantly as bedded stratabound replacement sheets, although the veins and solution-collapse breccias constitute important modes of occurrence. Brecciation, dolomitization, silicification and mineralization are interrelated. Post-Eocene intrusions and NW-SE and NE-SW trending faults are important ore controls. The ore mineralogy is simple and consists of barite and fluorite with very minor galena, pyrite, chalcopyrite, malachite and azurite. Sulfides are extremely rare in the deposit. At least two episodes of deposition have been identified: an early stage of fluorite precipitation and a later barite-fluorite mineralization event with spatial and temporal variations in salinity and temperature. Thermometric investigations indicate that homogenization temperatures (TH) for primary and pseudosecondary fluid inclusions in the fluorite range from 89 to 244oC with a mode at 150oC, whereas those for primary fluid inclusions in barite range from 119 to 323oC with two modes at 150 and 250oC. Evidence for boiling is seen during barite deposition. The mean salinities measured are 12 and 10 equivalent weight percent NaCl for fluids in fluorite and barite, respectively. Hydrocarbons in the inclusions hosted by fluorite samples were also detected. Chemical analyses of fluids extracted from inclusions in fluorite and barite show compositions dominated by Na, Ca and Mg ionic species. Barite shows d34S values between 22.6 and 26.7 per mil. The comparatively narrow spread in d34S values suggests very uniform environmental conditions throughout the mineralization field. Consideration of these data in their geologic context favors a basinal source for the oreforming fluids which have been significantly affected by heating during intrusive emplacement. The deposition of barite and fluorite resulted from physicochemical changes in Ba-F-rich hydrothermal brines during mixing with sulfate-rich formational water and wall rock interaction.

The German cockroach, Blattella germanica, is one of the most common pest species, and is a carrier of many pathogen and allergen factors in humans. Thus, regarding public health, the control of this insect is quite important. Dietary use of hormone analogues, especially juvenoids which disrupt reproductive organ development, is a relatively new method to control cockroaches. In this study, the effect of dietary juvenoid pyriproxyfen was investigated on these insects. The control groups received a regular diet with no juvenoid and each of the treatment groups received 10, 30, 50, 100, or 300 ppm of pyriproxyfen in their diets, respectively. For each dose, 15 fifth-instar nymphs were used and the experiment was replicated three times. Each of the experimental repeats had a separate control group. The treatment period was 14 days, then the insects were fed with a regular diet until they emerged into an adult. At this stage, the treated adults were kept with an untreated opposite sex until the formation of the first egg capsule. Use of pyriproxyfen was found to be effective in inducing abnormalities in wing formation such as divergent, curly wing and giant nymphs. Furthermore, dietary use of this juvenoid caused the sterility of the insects due to incomplete development of the internal reproductive organs. Various morphologic abnormalities like deformation and degeneration were observed in the ovaries and accessory glands of sterile insects. Histological investigation of testis and ovaries in infertile insects indicated a degeneration of ovarian follicle cells, defective vitellogenesis, hypertrophy of testis walls, spermatogenesis disorder and a decrease in the numbers of spermatocyts and spermatozoa. The external genitalia of the sterile insects in both sexes were not significantly altered compared with the controls.

Fracture mapping of Late Permian-Early Triassic flat-lying sedimentary rocks in the Sydney Basin, New South Wales, Australia, shows that joints developed originally in extension was faulted in subsequent events. Joints with a regional distribution fall into two (early and late) formed groups. Group I joints propagated horizontally and never interfered with each other. These joints were subsequently reworked or recracked. Recracking commenced with jointing and continued with lateral slip. Faulted joints grew horizontally by the linking of recracked segments. En echelon arrays are the result of the vertical propagation of faulted joints into intact rock. Recracking of rock also resulted in the formation of sets of secondary joints (Group II). The sense of movement on conjugate faulted joints and the orientation of the sets of secondary joints are related to three compressional stress fields. The intensity of recracking and the amount of lateral slip is mostly related to the strength of infilling materials, the length and continuity of the parent joint, the angle between the existing fractures and the maximum compression direction, and the number of compressional events imposed on the fracture.

To survive in natural waters, bacteria must respond to a variety of environmental variables such as starvation. Flexibacter chinensis was grown and multiplied in the starvation medium and its viable count, total count and cell size were investigated under different temperatures. Also, the effects of different nutrient sources were investigated. The survival of the organism under starvation conditions was temperature dependent with the longest survival occurring at 4oC and the shortest at above 30oC. Amendments of starvation medium with glucose or urea (as carbon and nitrogen source respectively) delayed the reduction in cell size and increased the survival time of F. chinensis at a number of different temperatures.

Holocene in Southwest Khuzestan is represented by a fluvio-tidal succession termed the Bahmanshir Series which consists of two clayey layers separated by silty sand to silt beds. This paper describes the geotechnical properties of the clayey layers that have wide exposure in the lowlands of the Persian Gulf coast. Studied layers are generally clay sized and consist of a lesser percentage of clay minerals. Most of the clayey layers have intermediate plasticity, and low potential for expansion. The variation of physical and engineering properties of the layers from base to top and along the Bahmanshir River is investigated in this research. The engineering properties of the beds seem to be affected by tidal and river flow currents and totally by their formation sedimentary environments. Links of the geotechnical data with geological features as formation sources in the upstream of the basin, the cementation due to the capillary feature in the floodplain sub-environment and the flocculated texture of clays in the brackish water, have been discussed in this paper. Overall, it is observed that the geotechnical data could be correlated with the geological features of the Bahmanshir Series.

A fauna of 16 species and genera of marine Ostracoda is described and illustrated for the first time from the mid-Cretaceous of the Badamouyeh Mountain in Kerman province. The ostracod assemblage suggests a favorable condition during the deposition of the strata. The ostracods can also be used for the correlation of Cenomanian age formations in many places in the Middle East.