Showing 59 results for jahromi
Volume 1, Issue 1 (NO. 1- 2011)
Abstract
Empowerment has high impact managerial and organizational efficiency and effectiveness. On the other hand, the role of entrepreneur people to create competence advantages is undeniable.
The advantages of the workplace spirituality (innovation, organizational commitment and so on) can make our organization an effective organization. So relationship between psychological empowerment, workplace spirituality and entrepreneurial behavior is the aim of this research. The conceptual model of research has been designed using these three variables. For this purpose, six hypotheses were tested. It was concluded that there is a significant relationship among three variables (psychological empowerment, workplace spirituality and entrepreneurial behavior).
Volume 1, Issue 2 (7-2014)
Abstract
Background: Asthma is the main reason of disability, health resource exploitation and low quality of life for those who are affected. It is estimated that nearly 300 million people in the world are suffering from asthma. Studies have identified 18 genomic regions and more than 100 genes associated with asthma. Among these candidate genes, IL-17F plays a very interesting role in asthma. This study was conducted to predict the conformational and functional impact of asthma-associated IL-17F polymorphisms on protein product of the corresponding gene using Phyre2, PolyPhen2 and SIFT softwares. Methods: In the present study, 10 significant missense SNPs (rs763780, rs144576902, rs11465553, rs368500268, rs141798304, rs2397084, rs146083682, rs200163061, rs376671742, and rs373228601) were taken from Ensembl Genome Browser database. Polymorphism-induced protein structural changes were predicted using Protein Homology analogY Recognition Engine V2.0 (PHYRE2) program. The possible impact of an amino acid substitution on the function of protein was analyzed using PolyPhen-2 (Polymorphism Phenotyping Version2) and SIFT (Sorting Intolerant From Tolerant) tools. Results: The analysis revealed mutant proteins having structural changes in the number of atoms, H-bonds, turns and helices. While wild copy has 82 H-bonds, 5 helices and 20 turns, the mutant types show considerable changes. At functional level also, substantial changes were observed between the wild protein and the mutant one. Conclusion: A single nucleotide polymorphism in the gene sequence can lead to the substantial structural and functional variations in the protein product of the gene, a process that may account for etiology of a number of complex diseases including asthma.
Mehdi jahromi,
Volume 3, Issue 1 (11-2012)
Abstract
Plants infected by arbuscular mycorrhizal fungi can tolerate and recover more rapidly from different biotic and abiotic stresses such as soil water deficits than uninfected plants. Thereby study of the dominant mycorrhiza species in the fields under drought stresses is very useful for increasing crop productivity in these conditions and promising for biological fertilizer production in the future. The objective of this research was to study the variations in morphological and molecular diversity of arbuscular mycorrhizal fungi (AMF) and identification of dominant AMF in wheat and barley fields of some arid and semi arid regions of Iran. For this purpose, about 66 samples containing root and rhizospher soils of wheat and barley plants were collected from some arid and semi arid regions of Iran (Isfahan, Tehran, Ghazvin, Arak, Tabriz). After trap culture of observed mycorrhiza in the samples, they were identified using morphological and molecular techniques. The ITS-rDNA of AMF in root DNA extracts of wheat and barley amplified with the primer pair LSU-Glom1/SSU-Glom1 as specific primer for AMF and ITS4/ITS5 as general primers in the first and second reactions of PCR (nested PCR), respectively. Aliquots of the positive second PCR products were cloned. Positive colonies were digested with Taq1. The restriction fragment length polymorphism (RFLP) patterns of digested samples were compared and 1-3 representatives of each pattern at each cloning reaction were sequenced. Morphological and molecular diversity of AMF showed that more than 90% AMF observed in the regions belong to genus Glomus which coordinates with morphological studies and followed by G. intraradices. Also these studies confirmed presence of following species in some regions: G. fasciculatum, G. geosporum, G. sinosum, G. constrictum, G. macrocarpum and Glomus sp. and Acaulospora (Acaulospora sp.). It is important to note that the species G. etunicatu and G. dimorphicum were not detected in the morphological studies and Glomus mosseae was the most dominant AMF species in the all studied regions.
Volume 3, Issue 3 (9-2014)
Abstract
In 2010- 2012 surveys, witches'- boom disease of tomato was observed in Borazjan area (Bushehr province, Iran). Agent of the disease was transmitted from tomato to tomato and eggplant by grafting and to Madagascar periwinkle via dodder inoculation, inducing phytoplasma-type symptoms in inoculated plants. Presence of phytoplasma in naturally affected tomatoes and all symptomatic graft and dodder inoculated plants was confirmed by direct and nested polymerase chain reactions (PCR) using primer pairs P1/P7 and R16F2n/R16R2. BLAST search and phylogenetic analysis of 16SrDNA showed that detected phytoplasma belonged to peanut witches'- broom (16SrII) group. Phylogenetic analysis, percent homology and virtual RFLP indicated that, as a member of 16SrII group, Borazjan tomato witches’- broom (BTWB) phytoplasma together with Bushehr eggplant and alfalfa witches’- broom (BEWB and BAWB, respectively) phytoplasmas were classified with Candidatus Phytoplasma australasia, a phytoplasma related to 16SrII-D subgroup. Based on the same analysis, BTWB, BEWB and BAWB phytoplasmas were differentiable from three other Iranian 16SrII related phytoplasmas associated with alfalfa witches'- broom diseases in Yazd and Fars provinces and lime witches'- broom disease in southern Iran.This is the first report of tomato witches'- broom disease and characterization of its associated phytoplasma in Iran.
Volume 3, Issue 4 (12-2014)
Abstract
The toxicity of thiamethoxam and pirimicarb on Diaeretiella rapae (Mc'Intosh) as a parasitoid of Lipaphis erysimi (Kaltenbach), exposed to residues on glass vials, was investigated under laboratory conditions at 23 ± 2 °C, 70 ± 5% RH and 16:8 h (L: D). Moreover, in order to find the negative impacts of both insecticides on the efficiency of D. rapae, the functional response of the exposed parasitoids were assessed. The newly emerged parasitoids were exposed to LC25 of the insecticides and distilled water as control. Host densities of 2, 4, 6, 8, 16, 32 and 64 were placed on canola seedlings in a transparent cylindrical container and were offered to the treated parasitoids. Type of functional response was determined by means of logistic regression method and the parameters, attack rate (a) and handling time (Th) were calculated by nonlinear regression model using SAS software. The parasitoid exhibited type II functional response in all experiments. Attack rates in control, pirimicarb and thiamethoxam were 0.057 ± 0.01,0.059 ± 0.013 and 0.040 ± 0.01 h-1, and handling times were 1.097 ± 0.1, 1.86 ± 0.02, 2.81 ± 0.296 h, respectively. Maximum rates of parasitism (T/Th) were estimated 21.87, 12.9, 8.53 aphids, respectively. These observations suggest that pirimicarb with less harmful effects is the preferred candidate for controlling the mustard aphid.
Volume 4, Issue 3 (12-2014)
Abstract
One of the new research domain which affect managers, researchers and scientific approaches is ambidexterity and its effect on all aspects of organizations. This means that how an organization can benefit from using simultaneously mechanisms of exploration and exploitation, and efficiency and innovation and be successful. In this paper authors reviewed the literature and theoretical foundations in the area of ambidextrous learning and its interaction with the intellectual capital (human capital, social capital and organizational capital) to adapt and develop an ambidextrous learning in organizations. Designed model is consistent with the logic of ambidexterity mode and is used 90 degree crossed modes to show results. In order to test the model, a questionnaire distributed among the senior executives of pharmaceutical industry. Companis data analyzed using content analysis and application of Max QDa. The results showed that for developing ambidextrous learning in organizations, all aspects of intellectual capital are needed to be Simulated Ranked with the concept of ambidextrous learning.
Volume 4, Issue 4 (Fall 2024)
Abstract
The main problem of philosophical hermeneutics is the problem of understanding. Understanding is determined in what context, how, and by what components. Gadamer explains these influential components by emphasizing tradition and history and emphasizes the plurality of understanding by expressing the ontological characteristics of human understanding. From this perspective, subjectivist and non-pluralist approaches are denied. In this article, we aim to examine, based on the characteristics of the understanding process in Gadamer's hermeneutic approach, namely historicity, pluralism, eventfulness, practicality, and linguistics, its relationship and proportion with political totalitarianism and pluralism, and to assess the possibility of convergence or incompatibility of the foundations of philosophical hermeneutics with political pluralism as a pluralistic political approach and divergence or compatibility of philosophical hermeneutics with political totalitarianism as a non-pluralistic political approach. Although Gadamer cannot be considered a full-fledged political philosopher, it is possible to examine political systems and their epistemological foundations based on his hermeneutic approach and evaluate their relationship.
Volume 5, Issue 1 (No.1 (Tome 17), (Articles in Persian) 2014)
Abstract
By emphasizing on the correspondences of linguistics and psychoanalysis, Julia Kristeva has presented new theories about the analysis of literary texts. “The Theory of Abjection”, which is derived of her post-structuralism researches, considers the author as a speaking subject who, through a poetic and semantic language, moves away from the ravages of his around. Kristeva has examined the applicative possibility of this theory in European literature. In this paper we focus on a contemporary Persian poem ("I am concerned for the garden" by Forough Farokhzad) for demonstrateing an application of the analytic approach of the “Theory of Abjection”. Hence, we aim two principal purposes: firstly, we try to represent an exhaustive panorama of the analytic approach of the Theory of Abjection, and secondly, we examine the possibility of creative interpretations of this poem According. Finally we try to examine the possibility of application of analytic approaches of this theory for the contemporary Persian poetry.
Volume 5, Issue 4 (12-2001)
Abstract
Godarz Eftekhar Jahromi
Professor of Law, Shahid beheshti University
Mohammad Issaei Tafreshi
Assistant Professor of Law, Tarbiat Modares University
Morteza Shahbazinia
Ph.D. Student of Private Law, Tarbiat Modares University
This article discusses the developments of legal regime of International Bank Guarantees, according to the Rules published by International Chamber of Commerce. This research shows that the main source of rules, governing this instrument, is usage and practice of international trade and attempts of ICC for applying of traditional legal rules inattention to international practice has been failed. Subsequently the chamber published "Uniform Rules for Demand Guarantees" (Publication No.458) in 1992. This new rules are mainly based on commercial usage and practice, and embraced the basic practical characters of bank guarantees as they are used in international trade; characters such as independence of guarntee and the effects of it. Also, the 458 Rules recognized issuance of simple demand guarantees and provide some practical resolves for other legal issues of bank guarantees such as providing of clear methods of ascertaining the applicable law and resolving disputes, limiting of bank duty to a formal compliance and accepting the documentary of bank guarantees.
Volume 5, Issue 13 (5-2017)
Abstract
Ta̕̕ ziye is crystalized as lyric, melancholic and popular rituals on the occasion of the martyrdom of Imam Hussein (AS) and his companions in the desert of Karbala in the year 61 AH. In general Ta̕̕ ziye and Shabihe are used interchangeably provided they are to some extent different. By the evolution of these two popular types, satire and humor have been emerged in Shabihhe. Also, it has been appeared a kind of educational –dramatic genre which was tragic, funny and was called ridiculous Ta̕̕ ziye as well. Ashqya humiliation, relief and scorn of Shiite mourning and mockery of symbols of power are among the functions of satire and humor in Ta̕̕ ziye. Some features of satire and humor language in Ta̕̕ ziye and Shabihe are: Antonymy , exaggeration , zooming out and colloquial form of everyday language. By adopting a descriptive – analytical research methodology, this study by reviewing the related literature tries to show that satirical expression and its techniques are widely used in dramatic works.
Volume 6, Issue 1 (7-2016)
Abstract
Introduction: Based on current estimations of different organizations, half of the world’s population live in cities, and these cities are the main consumers of energy. Cities have grand contribution in energy production of the world (around %60 to %80) and they have such enormous contribution in the emission of CO2. Energy is at the heart of the most critical economic, environmental and developmental issues facing the world today. Energy is essential to the delivery of urban services, and its role can be consid-ered vital at many stagesin the urban design process. This research begins with the planning and layout of a new cityand goes through to the socioeconomic structure of the city and its activities and the choiceof energy carriers and technologies used to meet the city’s energy demands. In recent years, there has been a surge of interest in urban climate and energy issues. LiteratureReview:Based on theories and history of energy consumption levels in different countries and with the consideration of sustainable development in the world, protection of energy resources became important and along continuing years, different approaches like smart growth, compact development, etc. have been introduced which shows the importance of this issue. Urban planning and design determines a city’s spatial, physical and managerial structure and influences directly and indirectly the energy consumption. Energy modeling in city scale is an ideal tool for studying energy consumption and reducing production of greenhouse gases in urban planning level. Models of urban efficiency evaluation in city scale is based on building, transport, etc. criterions and their great potential for consuming energy and producing greenhouse gases, can be proper guidelines for reducing energy consumption and in-creasing energy efficiency (EE). With regards to population growth and rapid urbanization, It seems es-sential to evaluate energy consumption and for improving its efficiency with different strategies. With regards to these issues, EE, either for protection of energy resources and optimum utilization of them, or for opposition with climate change and their pollutions, are issues which have importance in both nation-al and international dimensions. So, many actions have been accomplished which concentrate on two main issues: sustainable development and opposition with climate change. There are few studies about these issues, for example World Bank has worked in a few case studies such as Gaziantep in Turkey.In Iran, also based on done census in recent years, we have evolved in ur-banization through the increase of city›s count and immigration of villagers. There is also limited case studies in Iran, about the energy efficiency assessment in small scales, such as the neighborhood and building. So, nowadays, necessity of energy efficiency evaluation is important because of irregular energy consumption through optimized actions of urban planning which can reduce a city’s dependence on fos-sil energies and reduce costs and release financial resources for improvement of city services and social-economic advantages. Methodology: The purpose of this study is to determine the relationship between urban planning and energy efficiency, to present related approaches to this issue and to survey energy efficiency evaluation models with an emphasis to urban scale. Depending on the scale studied, models with different scales can be used to evaluate energy efficiency. Some models are used to study the energy efficiency in the scale of cities and others in lowers scales of a city’s divisions, such as districts and neighborhoods. Through studying EE models, we can identify their effective factors and existing barriers, as well as their performances. After considering the theoretical elements in evaluating the EE in city planning while fo-cusing on identifying different models and approaches to evaluate energy efficiency, two models in two levels have been chosen in this research: Firstly, TRACE model was chosen to evaluate the amount of energy consumption with different indices and criteria in the whole city of Tehran and the required sug-gestions were made for EE to be increased.TRACE is a decision-support system designed to help cities quickly identify and harness EE opportunities. It targets underperforming sectors, evaluates improvement and cost-saving potential,and helps prioritize actions for EE interventions. TRACE focuses on the munici-pal sectors with the highest energy use: passenger transport, municipal buildings, water and wastewater, public lighting and solid waste. Then, LEED model was chosen in the second level to evaluate energy efficiency more accurately in the districts of Tehran, and the sample neighborhood was Zahirabad in District 20 of Tehran which was studied with different indexes so that the EE in this area could be evaluated. The LEED is based on existing proven technology that drives market strength and credibility through the industry-wide development of LEED products. LEED is an initiative designed to actively promote the transformation of the mainstream towards more sustainable practices. Results:Results show that energy consumption evaluation can identify the High-power indicators and have an important role in reducing consuming energy of cities. In this study, in the initial level, Trace Model, based on comparison with other world cities, which has been included in presupposition of mod-el, and determination of their priority, building and transport indicators have been estimated as the most energy consumer parts of Tehran; And in the second level, in order to evaluate energy efficiency in neighborhood scale, has been done with LEED model which concentrates on most energy consuming indicators in first level -building and transport-. The score of neighborhood evaluation with LEED model is approximately acceptable based on this model and with regards to chosen criterions energy efficiency in neighborhood is in middle level and with changing certain situations we can increase EE in neighborhood. The survey of energy efficiency in one of the neighborhoods can provide a framework for evaluating other neighborhoods of Tehran in future studies and finally estimating EE in city level. Paying respect to time limitations, this neighborhood has been chosen just as a case, in order to use this model for other neighborhoods of Tehran and to recognize legal frameworks and development plans, policies and strate-gies for reducing energy consumption in different levels. Discussion and Conclusion: Research findings show that construction and transportation are the two most effective factors in the amount of energy consumption and efficiency. Resulting strategies from this study -based on tools and methods of energy efficiency evaluation- for reducing energy consumption and increasing energy efficiency include: promotion of mixed land-use, augmentation of density and compaction, development of public transportation, management and pricing parking, augmentation of pedestrian and bicycle accessibility and changing of energy consumption patterns at home, building and infrastructure parts, etc. Moreover, consideration of essentials in using reproducible energies in plan-ning can improve the utilization of these energies and increase energy efficiency. It ought to be said that in order to respond to the energy efficiency challenge in cities, it is important to choose a particular method with regards to native situations and city scale. With presenting proper strategies and changing in case studies, we can adjust energy consumption and go toward energy efficiency and a sustainable de-velopment. So, according to the results from analysis and proposed recommendations and strategies for improving energy efficiency in two scales, we can increase energy efficiency with setting policies and taking action.
Volume 6, Issue 1 (winter 2021)
Abstract
Aim: This study aimed to investigate the effect of two weeks of vitamin D3 supplementation on some indices of Delayed Onset of Muscle Soreness (DOMS) after eccentric exercise.
Method and Materials: In this semi experimental study, 20 nonathletic male collegiate students (19.75±1.29 years) participated in the study voluntarily and were divided randomly into two groups of experimental (n=11) and placebo (n=9). The experimental group consumed vitamin D3 (Cholecalciferol) containing 50000 IU while the placebo group took apparently similar capsules containing starch like, two capsules for two weeks. To induce DOMS, participants performed a step protocol that included four sets (5 minutes for each set), with a 1-minute of rest interval between each set using a 46 cm-step. Range of Motion (ROM) of low extremity joints and circumferences, and Visual Analog Scale (VAS were measured before, immediately after (Time 0), and 24 hours (Time 1) and 48 hours (Time 2) after eccentric exercises.
Findings: This study showed that thigh Thigh circumference increased following eccentric exercise in the placebo group, while it did not change significantly in the experimental group (p>0.05). There was no significant difference between the two study groups regarding other variables (P>0.05). Vitamin D3 supplementation with the dosage and duration used in the present study reduced the limited symptoms of DOMS. Future studies of longer duration or higher dosage of vitamin D supplementation are recommended.
Conclusions: According to the finding of this study, vitamin D3 supplementation could not reduce the limited symptoms significantly. However, future studies are suggested to evaluate the effect of higher dose or longer duration of vitamin D supplementation on DOMS.
Volume 6, Issue 4 (No.4 (Tome 25), (Articles in Persian) 2015)
Abstract
Yuri Lotmn (1993-1922) is the founder of the Moscow-Tartu school. He has a distinguished role in introducing and developing the “Theory of Intercultural Semiotics”. In Lotman’s opinion, cultural semiotics considers each text as a cultural totality. The existing signs in the text could indicate the way in which the significances are produced to achieve a certain specific meanings in a culture. Hence, cultural semiotics can choose many texts that belong to a social and historical ambiance for recognizing the cultural and social infrastructures of that period. In fact, it could be an analytic approach, which envisages the cultural productions of a particular section and the survey of intertextual relations, interactions and dynamic relationships between them.
In this article, we rely on the movie The Private Life of Mr. and Mrs. M. (2011) directed by Ruhollah Hejazi as a cultural product of a particular period. The analysis of this text's themes and its dynamic relationship with other texts shows a considerable part of the cultural phenomenon in this period. Finally, this study aims to reveal common themes and processes in the meaning interdependency between these texts
Volume 7, Issue 1 (3-2018)
Abstract
The toxicity of garlic is confirmed on some agricultural pests. The aim of this study was to comparatively evaluate the sensitivity of
Podisus maculiventris (Say) to garlic extract and two insect pests:
Mediterranean flour moth Ephestia kuehniella (Zeller) and Colorado potato beetle
Leptinotarsa decemlineata (Say). LC
50 was calculated at 8.02% for
E. kuehniella. The results showed toxic compounds in garlic extract delayed all developmental stages and reproduction parameters of
L. decemlineata. In contrast, there were no considerable negative effects on many of the biological parameters of the predatory insect,
P. maculiventris. The results suggest that garlic, as a green pesticide, could be considered an environmentally suitable alternative in pest management programs.
Volume 7, Issue 2 (6-2021)
Abstract
In this study, the distribution of 88 species of the family Megachilidae, out of 3678 specimens in the Iranian Pollinator Insects Museum of Yasouj University (IPIM), which were collected in spring and summer 2009–2017 from different regions of Iran including Ardabil, Chaharmahal-o Bakhtiari, Fars, Golestan, Isfahan, Kerman, Khuzestan, Kohgiluyeh-va Boyer-Ahmad, Sistan-o Baluchestan, Alborz, are presented. Data on the number of specimens, locations, coordinates and distribution maps for Iran and global distribution of all species (where available) are also provided. Megachile (Megachile) octosignata Nylander 1852 is first recorded from Iran. Ninetheen species are reported for the first time from Chaharmahal-o Bakhtiari and Kohgiluyeh-va Boyer-Ahmad Provinces.
Volume 7, Issue 2 (Spring 2021)
Abstract
Backgrounds: This study aimed to assess antibacterial properties of Artemisia scoparia, Titanium dioxide nanoparticles, and their synergistic effect on clinical isolates of Klebsiella pneumonia.
Materials & Methods: In this experimental study, 30 isolates of K. pneumonia were collected from patients’ sputum in the microbiology lab of Masih Daneshvari hospital during 3 months. Then biochemical tests were performed for strain confirming. Moreover, genomic DNA was extracted from all the isolates, and hly gene was detected in the isolates via PCR method. The susceptibility of the isolates to 10 antibiotics was evaluated by the disk diffusion method. Then minimum inhibitory concentration (MIC) of all components (Artemisia extract, TiO2, and their combination) was assessed using the microdilution method against the isolates.
Findings: The results indicated that simultaneous use of hydro-alcoholic extract of A. scoparia and titanium dioxide nanoparticles exhibited a significant synergistic antibacterial effect on 25 clinical isolates in comparison with the use of extract or nanoparticles alone.
Conclusion: It seems that simultaneous use of Artemisia herbal extracts and nanoparticles is beneficial in increasing their antibacterial effect and may decrease antibiotics consumption.
Volume 7, Issue 4 (9-2018)
Abstract
The effects of four insecticides, abamectin (1500 and 750mgl-1), emamectin benzoate (1000 and 500mgl-1), acetamiprid (500 and 250mgl-1), and flubendiamide (500 and 250mgl-1), were studied on different preimaginal stages of T. brassicae and T. evanescens, the egg parasitoids of tomato leaf miner Tuta absoluta (Lepidoptera: Gelechiidae). Parasitized eggs of the Angoumois grain moth Sitotroga cerealella (Lepidoptera: Gelechiidae) were treated by the dipping method at the larval, prepupal, and pupal stages of the parasitoid. For persistence evaluation, the insecticides were applied at the recommended concentration on tomato plants by a hand sprayer till runoff point. Plants were maintained under a transparent polyethylene rain cover in the field. Leaves of the treated tomato plants were sampled and transferred to the laboratory at time intervals of 3, 5, 16, and 31 days after application. Based on our study, abamectin was the most harmful insecticide for immature stages of both parasitoids T. brassicae and T. evanescence. Treatment by abamectin at the pupal stage had more adverse effects compared to prepupal or larval stages. Acetamiprid with 30.5% and 31.6% mortality in less than five days was classified as the short-lived insecticide for T. brassicae and T. evanescens, respectively. The same result was obtained in flubendiamide treatment which caused 27.2% and 26.1% mortality to the parasitoids, respectively. Abamectin with 16.1% and 13.8% mortality in less than 16 days was slightly persistent. However, emamectin benzoate with 13.3% and 15.5% mortality in less than 30 days was classified as moderately persistent for those two species, respectively. Therefore, flubendiamide and acetamiprid were non-harmful to both T. brassicae and T. evanescence wasps and are good candidates to be incorporated into IPM programs in combination with biological agents for the control of tomato leaf miner T. absoluta. By contrast, emamectin and abamectin should be used with greater care as a part of an IPM procedure.
Volume 8, Issue 3 (10-2008)
Abstract
Budget deficit and ways of its financing,have different economic implications.The private consumption as one of the major components of the aggregate demand alongside with the private investment are also under the effects of the deficit.The total effects of the deficit can be separated into the primary and secondary effects.The primary effects of the defict is attributed to the causes of the deficit,while the secondary effects is related to the ways of deficit financing.The final effect is the sum of these two effects,which might be positive,negative or zero.The results of the study by the ARDL approach for the time period of 1342-1384 indicates that although the effect of the deficit on private consumption is positive but there is no longrun relationship between them.On the other hand effects of the deficit on private investment is negative.These results also show that the effects of the deficit on investment may last or endure for a long time and therefore it can be said that there is a longrun relationship between deficit and private investment.
Volume 9, Issue 1 (Winter 2023)
Abstract
Backgrounds: This study was conducted with the aim of isolation and molecular identification of Streptomyces spp. producing antibacterial compounds from Iranian soil.
Materials & Methods: In this study, 50 soil samples were collected from different areas of Sanandaj city. Soil samples were cultured on starch casein media. Streptomyces species were characterized using morphological and biochemical assays. Molecular identification was performed by 16S rRNA sequencing. Antimicrobial activity was evaluated using perpendicular streak and agar well diffusion methods.
Findings: To identify active Streptomyces strains in terms of producing antibacterial agents, screening was performed in two stages. Among 20 Streptomyces strains isolated from soil samples, six isolates were selected in the primary screening stage based on their ability to limit the growth of pathogens. Of the two solvents used in the secondary screening stage, ethyl acetate was the most suitable solvent for extracting effective metabolites of Streptomyces. Among the six isolates selected based on their antimicrobial activity, two isolates with the highest antibacterial activity were selected for the sequencing process. By analyzing the dendrogram and the data obtained from the NCBI database, it was found that one isolate (Yellow 4A) was 98% similar to S. fradiae, and the other isolate (Green 4A) was 98% similar to S. coelicolor.
Conclusion: The use of proper strategies to identify potential new Streptomyces species with antibacterial properties may bring a bright future in the treatment of resistant pathogens. However, more studies are required to detect active metabolites of the mentioned isolates.
Volume 9, Issue 2 (2-2020)
Abstract
The western flower thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is an invasive pest in greenhouse with high potential to cause damage to crops. There are a limited number of effective insecticides to manage this pest and several cases of chemical control failures have been reported in Iran which can be due to resistance to insecticides. To evaluate the status of insecticide resistance and possible resistance mechanisms, eight Iranian strains of F. occidentalis, collected from Tehran, Markazi, Alborz, Qazvin, Isfahan, Yazd (M and B) and Kerman provinces, were assayed against dichlorvos as a recommended insecticide for chemical control of thrips. Compared with the susceptible strain (Isfahan), two strains collected from Yazd had the lowest susceptibility to dichlorvos (Resistance Factor = 2.14 and 2.04 fold). Bioassay by synergists and enzyme assays demonstrated interfering of carboxyl esterase and glutathion S- transferase in Yazd M strain. The esterase inhibitor, triphenyl phosphite (TPP), and Glutathione S-transferase inhibitor, diethyl maleate (DEM), synergized the toxicity of dichlorvos in the Yazd M strain, (Synergistic Ratio = 5.28 and 1.79 fold, respectively). Also, carboxylesterase (for α- naphtyl acetate and ß- naphtyl acetate) and glutathion S- transferases activities in this population were 1.69, 7.31 and 0.97 fold higher than in the Isfahan strain. Furthermore, dichlorvos resistance did not significantly diminish after several months. Based on our results, we suggest that dichlorvos should be removed from the control program of this pest.