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11.
The genus Pythium, with slightly over 280 described species has been classified traditionally with other filamentous, coenocytic, sporangia-producing fungi as “Phycomycetes”. However, with recent advances in chemical, ultrastructural and molecular studies Pythium spp. are now considered as “fungus-like organisms” or “pseudo-fungi” and are placed in the kingdom Chromista or kingdom Straminopila, distinct from the true fungi or the kingdom Fungi. Little is known about the biodiversity of Pythium in Iran. This paper attempts to assess the position of the genus Pythium and provides details of the historical development of the study of Pythium in Iran. The survey list contains 33 species, 4 species groups and 1 unknown species of Pythium.  相似文献   
12.
Several species of the genus Alternaria are involved in leaf spot disease of sunflower, with Alternaria alternata being the dominant species responsible for this disease in Iran and many other sunflower-producing areas, worldwide. The disease causes a progressive destruction of the photosynthetic apparatus, resulting in annual yield loss. The routine disease management strategies are not effective for disease control; hence, alternative measures for disease management are of great interest. In the present study, the efficacy of Trichoderma harzianum T22 and Trichoderma sp. on biological control of the causal agent was evaluated under laboratory conditions. The effect of Trichoderma isolates on dry weight (DW) and radial growth (RG) rate of A. alternata was evaluated using dual culture, volatile and non-volatile cellular metabolites. The results obtained in this study revealed that in both Trichoderma isolates, non-volatile cellular metabolites had the highest inhibitory effect on DW and RG rate of the causal agent. Owing to explicit inhibitory effect of non-volatile cellular metabolites on A. alternata, the inhibitory effects of different concentrations of non-volatile cellular metabolites were evaluated on DW and RG rate of the A. alternata. The obtained results showed that non-autoclaved 75 and 50% concentrations and undiluted (100%) autoclaved non-volatile cellular metabolites from Trichoderma sp. had the highest inhibitory effect on DW and RG rate of the causal agent. The overall results of this study reveal that Trichoderma spp. have excellent efficacy on biological control of A. alternata under laboratory condition; such that, further studies on the potential of Trichoderma spp. in biological control of Alternaria leaf spot disease of sunflower under green house and field conditions are necessary.  相似文献   
13.
Abstract

The Kopet-Dagh Basin is a large sedimentary basin in northeastern Iran that host the giant Khangiran and Gonbadli gas fields. The Mozduran Formation with its various sedimentary facies is an important reservoir widely distributed in the basin. A sedimentological analysis of Upper Jurassic Mozduran Formation resulted in an accurate reconstruction of the sedimentary environments and the sequence stratigraphic framework south of Aghdarband. The strata consist of six different facies associations including 12 carbonate, one evaporate and two siliciclastic subfacies. On the basis of their various components, structural and textural characteristics, these facies were deposited on a homoclinal ramp in tidal flat to open marine environments ranging from supratidal to subtidal settings. Facies A1 and A2 represent open marine, B1-B4 Shoal, C1-C4 lagoonal and D1, D2, E, T1 and T2 tidal flat and Salina environments. In addition, based on detailed field and laboratory studies on the facies architecture, several large-scale (long-term) depositional sequences could be distinguished in the stratigraphic sections of the study area. These sequences are composed of LST, TST and HST that are separated by a SB1 and SB2 sequence boundaries. The paleogeography of the study area during the Late Jurassic time is reconstructed in five block diagrams.  相似文献   
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Purpose

The main purpose of this study was to evaluate the use of an integrated life cycle assessment (LCA), artificial neural network, and metaheuristic optimization model to improve the sustainability of tomato-based cropping systems in Iran. The model outputs the combination of input usage in a tomato cropping system, which leads to the highest economic output and the least environmental impact.

Methods

The LCA inventory was created using data from 114 open-field tomato farms in the Alborz Province of Iran during one growing period in 2015. Among all management components, the main focus was on irrigation management systems. The optimization problem was designed by integrating three indicators: carbon footprint (CF), benefit-cost ratio (BCR), and energy use efficiency (EUE) as the objective of field tomato production. The functional unit was 1 kg of tomato aligned with the system boundary of the cradle to market life cycle. Three artificial neural networks (ANNs) were applied to model relationships between the inputs and three indices (CF, BCR, and EUE) as the objective functions. Multi-objective genetic algorithm (MOGA) and multi-objective particle swarm optimization (MOPSO) were used to minimize the CF and maximize the BCR and EUE indicators. The abovementioned aims have been pursued by developing codes in MATLAB software.

Results and discussion

CF, BCR, and EUE were calculated to be 0.26 kg CO2?eq (kg tomato)?1, 1.8, and 0.5, respectively. MOGA results envisage the possibility of an increase of 86% and 50% in the EUE and BCR and a 43% reduction in the CF of tomato production systems. Moreover, EUE and BCR increased by 83% and 49%, and CF was reduced by 39% from the optimum results obtained from the MOPSO algorithm. It was revealed that in order to optimize field tomato production with the target objectives of this study, a large additional use for irrigation pipes, plastic, and machinery in comparison to current situation is required, while a large reduction of biocide, chemical fertilizer, and electricity consumption is indispensable.

Conclusions

According to the results of our study, it was concluded that the optimal solutions require a modernization of irrigation systems and a decrease in the consumption of chemical fertilizers and pesticides. The implementation of management options for such solutions is discussed.

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15.
The interaction of two water soluble phthalocyanines, cobalt(II) 4,4′,4″,4‴-tetrasulfo-phthalocyanine (CoTsPc) and iron(II) 4,4′,4″,4‴-tetrasulfo-phthalocyanine (FeTsPc), and one water soluble porphyrin, tetra sodium mesotetrakis(p-sulfophenyl)porphyrin (TSPP), with calf thymus DNA has been studied by UV-Vis spectroscopy at five different temperatures (20, 25, 30, 35, and 40°C). The optical absorption spectra of these materials were analyzed to obtain binding constants and stoichiometries using SQUAD software. The results show that the best fitting corresponds to a 1: 1 complex model between a base pair of DNA and these materials. All of the studied porphyrin and phthalocyanines showed strong electrolyte effect, and increasing NaCl concentration induced self-aggregation of these materials. Published in Russian in Biokhimiya, 2007, Vol. 72, No. 6, pp. 799–804.  相似文献   
16.
Gold nanoparticles (GNs) have unique characteristics, for example, stability, biocompatibility, small dimensions, and low toxicity. Several clinical applications have been suggested for GNs, such as diagnosis, imaging, and drug delivery. GNs absorb infrared light, indicating their potential value for imaging. There is growing evidence showing the therapeutic application of GN for drug delivery because of their interaction with the blood-brain barrier and DNA, the latter being associated with their genotoxic effects. GN can also be stimulated to produce high local temperatures, indicating their potential value in photodynamic therapy in the treatment of tumors. The aim of the current review is to summarize the potential applications of GNs in the biomedical field, specifically in neurodegenerative diseases.  相似文献   
17.
International Journal of Peptide Research and Therapeutics - Our study aims to establish a biocompatible nanostructure for the improved delivery of anticancer peptide, Brevinin-2R, to treat human...  相似文献   
18.
The Kopet-Dagh Basin is located in northeastern Iran and southern Turkmenistan. The Late Maastrichtian Kalat Formation caps the Cretaceous interval in this Basin. Based on eight measured stratigraphic sections, the depositional environments and the sea-level history of the Kalat Formation have been interpreted. Petrographic and field observations led to identification of four major carbonates (A–D) and two siliciclastic lithofacies types. Carbonate rocks were deposited on a ramp setting within three zones including restricted and semi-restricted lagoons, bars, and open marine environments, while the siliciclastics were deposited at the shoreline. Sequence stratigraphic analysis identified two depositional sequences in the western and eastern parts and three depositional sequences in the central parts of the study area. Comparing the sea-level curve of Late Maastrichtian time in the Kopet-Dagh Basin with the global sea-level curve for the same time interval, there are some geometrical similarities and differences. The variations in the Basin are related to regional tectonic settings and sediment loading of the study area. Reconstructions of depositional environment during eight time slices of the Late Maastrichtian are presented. These results could be used for comparison with other localities worldwide and provide additional data for Late Cretaceous paleogeographic reconstructions.  相似文献   
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