فهرست مطالب

Sciences, Islamic Republic of Iran - Volume:26 Issue: 4, Autumn2015

Journal of Sciences, Islamic Republic of Iran
Volume:26 Issue: 4, Autumn2015

  • تاریخ انتشار: 1394/09/30
  • تعداد عناوین: 7
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  • S. Dashti Aghjeh, A. Aramvash Pages 303-313
    Polyhydroxyalkanoates (PHAs) are bioplastics derived from renewable resources such as vegetable oils, corn starch, or microbes. The polyhydroxybutyrate (PHB) is a short-chain-length PHA, and the most important bioplastic produced by certain microorganisms in the presence of excess carbon sources. In this study batch cultivation of Alcaligenes eutrophus with the aim of increasing PHB production using different carbon and nitrogen sources was performed. The accumulation of PHB granules in this strain was significantly dependent on the type of carbon and nitrogen sources in the culture medium. The bacteria were cultivated on various carbon sources including glucose, fructose, lactose, lactic acid, arabinose and sucrose and nitrogen sources including ammonium chloride, ammonium sulfate, peptone, urea and tryptone at constant concentrations, temperature and pH. Cell growth and PHB production were quantified by measuring absorbance at 600 nm and 235 nm (absorbance of crotonic acid), respectively. The best results were obtained when using fructose and ammonium chloride as carbon and nitrogen sources, with a carbon/nitrogen ratio of 10. The production of PHB was growth associated as indicated by the growth and PHB production kinetics. Atomic force microscopy analysis of PHB film also showed high porosity of PHB recovered by chloroform.
    Keywords: Alcaligenes eutrophus, Carbon source, Incubation time, Polyhydroxybutyrate, Nitrogen source
  • B. Laamerad*, P. Ansari Pages 315-319
    Cellulolytic complex are enzymes capable of hydrolyzing cellulose. Due to rapid growth in population and industrialization, most countries are required to produce more fuel. Production of bioethanol from lignocellulosic biomass is very challenging due to environmental pollution by fossil fuels. Cellulases play a significant role in biotechnological processes. The cost of production of cellulase is very high. Approximately 50% of the cost of producing bioethanol is used to produce cellulose. Gibberellin regulates the growth of fungi and plants. Cellulase production was significantly improved by gibberellins hormone. The cellulase activity was 4.29 FPU/ml (when we used 50 μmol/ml of gibberellins in culture medium). This was 12- fold higher (0.34 FPU/ml in control solution) compare with untreated hormone and was comparable to that achieved with concentrated by n- butanol. In this experiment, the enzyme activity was increased 223- fold higher compare with control solution.
    Keywords: Trichoderma reesei, Gibberellins, Cellulose, Butanol
  • T. Akbarzadeh*, A. Rafinejad, A. Fallah, Tafti, R. Tiwari, A. Nasrolahi Shirazi, D. Mandal, K. Parang, A. Foroumadi Pages 321-325
    In this work, different ethyl 2,4-dioxo-4-arylbutanoate derivatives were prepared and evaluated for their Src Kinase inhibitory activity. For this purpose, the appropriate substituted acetophenone derivatives reacted with diethyl oxalate in the presence of sodium ethoxide in dried ethanol to give the corresponding products. All compounds showed moderate activities comparing with staurosporine as the reference drug.
    Keywords: Ethyl 2, 4, dioxo, 4, arylbutanoates, Src kinase, Cancer
  • B. Mirza, M. H. Sayahi Page 327
    In this work, different ethyl 2,4-dioxo-4-arylbutanoate derivatives were prepared and evaluated for their Src Kinase inhibitory activity. For this purpose, the appropriate substituted acetophenone derivatives reacted with diethyl oxalate in the presence of sodium ethoxide in dried ethanol to give the corresponding products. All compounds showed moderate activities comparing with staurosporine as the reference drug.
    Keywords: Ethyl 2, 4, dioxo, 4, arylbutanoates, Src kinase, Cancer
  • S. M. Niktabar, A. Moradian, H. Ahmadipour, J. F. Santos, M. H. Mendes Pages 333-348
    The Lalezar granitoids crop out within volcanic successions of the Urumieh-Dokhtar Magmatic Assemblage (UDMA). These granitoids have a range from gabbro-diorites to granites in composition. The mineral compositions of the most felsic rocks are characterized by the abundances of Na-plagioclase, quartz, alkali feldspar, biotite and hornblende. In the gabbro-diorite rocks, plagioclase (Ca-rich), hornblende, biotite and clinopyroxene are the most common minerals. Major element geochemical data show that the Lalezar granitoids are mostly metaluminous, although the most felsic members (granites) attain slightly peraluminous compositions and that they have features typical of high-K calc-alkaline rocks. In primitive mantle-normalized trace element spider diagrams, the analysed samples display strong enrichment in LILE compared to HFSE, accompanied by negative anomalies of Nb, Ta and Ti. REE chondrite-normalized plots show moderate LREE enrichment with slight to strong negative Eu anomalies. Rb–Sr geochronological data, mainly dependent on the Sr isotopic composition of biotite, was obtained in two samples and it points to 15-16 Ma. As a probable, age for the emplacement of the studied intrusives. Initial 87Sr/86Sr ratios and ƐNdi values range from 0.70495 to 0.70565 from +3.1 to +1.5 respectively, which fit into a supra-subduction mantle wedge source for the parental melts and indicates that, in general, crustal contribution for magma diversification was not relevant. Geochemical and isotopic evidence reveal that the Lalezar intrusions are cogenetic I-type granitoids which were generated in a continental arc setting, in agreement with models previously presented in the UDMA.
    Keywords: Lalezar, Calc, alkaline, Granitoids, Petrogenesis, Isotopic composition
  • A. Aasaraai Pages 349-354
    To start with, having employed transformation wave, some nonlinear partial differential equations have been converted into an ODE. Then, using the infinite series method for equations with similar linear part, the researchers have earned the exact soliton solutions of the selected equations. It is required to state that the infinite series method is a well-organized method for obtaining exact solutions of some nonlinear partial differential equations. In addition, it is worth mentioning that this method can be applied to non-integrable equations as well as integrable ones. This direct algebraic method is also used to construct the new exact solutions of the three given examples. It can also be claimed that any equation matching the special form which has been made in this article, will be solved immediately by means of infinite series method.
    Keywords: Infinite Series method, Davey, Stewartson (2+1), dimensional equation, Generalized Hirota, Satsuma coupled KdV equation, Phi, four equation
  • F. Ghapani, A. R. Rasekh, M. R. Akhoond, B. Babadi Pages 355-366
    The aim of this paper is to propose some diagnostic methods in linear ridge measurement error models with stochastic linear restrictions using the corrected likelihood. Based on the bias-corrected estimation of model parameters, diagnostic measures are developed to identify outlying and influential observations. In addition, we derive the corrected score test statistic for outliers detection based on mean shift outlier models. The analogues of Cook's distance and likelihood distance are proposed to determine influential observations based on case deletion model. A parametric bootstrap procedure is used to obtain empirical distributions of the test statistics and a simulation study has been given to show the performance of the score test statistic. Finally, the proposed diagnostic procedures are illustrated on a numerical example to show the theoretical results.
    Keywords: Case deletion, Corrected likelihood, Influential observations, Mean shift outlier model, outliers