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Shahrechay Dam is located at 12^th Km of Shahrechay River in Urmia. This study was conducted for a year (Spring to fall, 2007) to identify different species of benthic organisms in the dam. Considering the relevant topographic status like the local depth and water speed, 6 sampling stations were chosen and sampling was done in shallow locations of the river by means of superficial method. In this study, 2 phylums, 2 orders, 13 families and 21 species of benthic organisms were identified in Shahrechay Dam Lake. The results indicated that the highest species diversity belonged to Ecdyonuridae family (Eperous Genus). In terms of frequency, it belonged to Tibuficidae (Tubifex Genus), with 43%, 23%, and 11% ratios for spring, summer, and fall, respectively. The final result of the research demonstrated the poverty of lake bed from view of the benthic quantity and density. Therefore, the Shahrechay Dam was not a suitable candidate to develop fishery’s purposes, especially releasing and growing Cyprinidae fishes and other benthos-feeder aquatics.

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Aims: Methicillin resistant Staphylococcus aureus (MRSA) strains are a major contributor to the development of hospital- and community-acquired infections. The aim of this study was to evaluate the polymorphism of mecA gene, frequency of blaZ gene, and detection of mecA promoter mutations in clinical isolates of methicillin-resistant S. aureus strains.
Materials & Methods: Susceptibility of 85 S. aureus clinical strains to methicillin was evaluated using disc diffusion method. The polymorphism of mec-associated hypervariable region (HVR), presence of blaZ genes, and mutation in mecA promoter were determined by PCR and sequencing.
Findings: A total of 40 (47.1%) out of 85 S. aureus isolates were identified as methicillin resistant by phenotypic assays and PCR-based detection of mecA gene in MRSA strains. Seven different groups of repeats were found among these strains. Also, 39 MRSA strains harbored blaZ gene, and according to the sequence analysis of mecA promoter, R226S mutation was identified in 1 out of 10 isolates tested.
Conclusion: According to the obtained results, there was a high variation in the polymorphic region of mecA gene in clinical isolates of S. aureus. In addition, it was appeared that beta-lactamase enzyme production and antibiotic hydrolysis played an important role in the occurrence of resistance to beta-lactam antibiotics, and the effect of mutation in genes regulating mecA gene expression was negligible.

 
 

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Aims: This study aimed to determine the antibiotic resistance pattern of Pseudomonas aeruginosa clinical isolates and the frequency of blaSIM and blaAmpC genes in resistant strains.
Materials & Methods: In this cross-sectional study, 94 P. aeruginosa isolates were collected from the burn wards of Gilan province hospitals in 2018 and identified by biochemical methods. Strains producing β-lactamases and metallo-β-lactamases were detected by two methods: disk diffusion method and antibiotic resistance method in combination with disk diffusion method, respectively. The presence of blaSIM and blaAmpC genes in the resistant strains was investigated using PCR, and data analysis was performed.
Findings: Based on the obtained results, colistin was identified as the most effective antibiotic with a resistance rate of 27.7%, and the highest antibiotic resistance was observed against trimethoprim/sulfomethoxazole (83%). In the phenotypic test of 94 samples, 29 (30.9%) carbapenemase-producing isolates and 33 (35.1%) β-lactamase-producing isolates were identified. Based on the PCR results, among 44 (46.8%) samples containing β-lactamase and carbapenemase enzymes, the frequency of blaSIM gene was 9.1% (4 of 44, and 4.3% in all the studied isolates), and the frequency of blaAmpC gene was 15.9% (7 of 44, and 7.4% in the all studied isolates).
Conclusion: The results of this study indicated a high prevalence of drug resistance in clinical isolates of P. aeruginosa. In particular, there was an increasing rate of resistance to beta-lactam antibiotics, and the presence of MBL and ESBL associated genes was considerable, which limit the choice of suitable treatment for patients with severe infections.

 

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Selco enriching emulsion includes compounds from certain oils with marine and herbal origins. Selco oil produces micro-globules with less than 0.1 micron diameter. In order to generate such stability in original selco chemical emulsifiers have been used up to 3%. In this study, persian gum )Amygdalus scopariaspeech( and salep (Orchis mascula (were used as herbal emulsifiers in synthesis of Artemia enriching for a content of 11% to establish emulsification. The soluble part of persian gum and salep was separated with 30% and 22% content, respectively. Through chemical analysis, the chemical composition of the imported Selco oil was identified. Then the similar ingredients of the commercial brand were combined to produce our synthesized production. In physical computing, the average diameter and distribution of oil phase particles side was obtained as 0.1 micron and the relevant surface tension as 15±5 DIN/cm. Then the synthesyzed enriching oil (treatment 1) with the imported one (treatment 2) were tested for Artemia urmiana enriching with standard conditions. Enriching conducted in 3 repetitions with 0.4 gr/lit of the enriching oils/1 lit of water. Nauplii were introduced as 200000 nauplii/lit. The average of nauplii enriching percentage in treatments 1 and 2 was achieved as 27±2.47 and 23±2.52 percent, respectively. The bioassay results on 500 new feed larvae of trout fish has been shown that treatments 1 and 2 were significantly differed in survival. Therefore, the plant emulsifiers in this study, showed good performances as the chemical and physical properties, in stabilizing the oil emulsion in the aqueous phase.

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Chitin and chitosan are two very important biopolymer products that have so many usages in the high cost industries. Chitin Converts into chitosan via de-acetylation of chitin. It occurs by alkaline melting method in the absence of oxygen. Chemical structure change, severe environmental pollution and De-polymerization are of the major problems in producing high quality chitosan. In this study for conversion of chitin into chitosan fungus Aspergillus niger strains (ATHUM-10864), the generator of de-acetylases enzymes were used instead of chemicals. Chitosan quality was determined via elemental analysis infrared spectroscopy, X-ray tomography, molecular weight determination and estimation of crystallinity percent, color and molecular structure.The results showed 80±5% efficiency in the conversion of chitin into chitosan or de-acetylation degree of chitin. The gained chitosan contained of 44.4 % carbon, 8.9 % nitrogen, 2.7 % hydrogen and 39.5 % oxygen. The physical characteristics were as 94.5% Crystallinity and pale brown color. The chemical structure of per unit of chitosan was obtained as C6H12NO4. The results showed that replacing biological methods instead of chemicals was possible to access well quality products. It also eliminates the use of chemical materials such as concentrate sodium hydroxide that is damaging the environment.

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Background: Mupirocin is a topical antibiotic inhibiting most Gram-positive cocci. Shortly after taking mupirocin, drug resistance emerges. This study aimed to determine mupirocin resistance in Staphylococcus aureus strains isolated from clinical specimens in Rasht.
Materials & Methods: In this study, a total of 85 clinical isolates of S. aureus were collected. Biofilm formation ability and antibacterial resistance patterns of isolates were investigated. Disc diffusion method and MIC determination were used to determine the susceptibility of strains to mupirocin antibiotic. Agr types, the presence of mupA, and mutation in ileS-1 were evaluated in mupirocin non-susceptible isolates by PCR and PCR sequencing, respectively.
Findings: Out of 85 tested strains, 57 (67%) isolates were recognized as biofilm producers, and all of which showed multidrug resistance phenotype. Agr type 1 was the most commonly detected type. Additionally, 12 mupirocin-resistant strains were identified in the disc diffusion and MIC tests. A total of four strains were mup-A positive and showed high-level resistance. In sequencing and mutation evaluation of the ileS-1 gene in eight low-level mupirocin-resistant strains, 12 types of silent mutation and one type of missense mutation were determined.
Conclusion: The study of mupirocin-resistant strains in this study showed the need to identify factors affecting the occurrence of resistance and to take control and prevention measures before mupirocin losses its efficacy.

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Backgrounds: This study was done to evaluate the distribution of virulence-associated genes and antibiotic resistance in avian colibacillosis-causing Escherichia coli (E. coli) isolates.
Materials & Methods: In this study, 122 E. coli strains isolated from colibacillosis-suspected chickens in commercial broiler poultry farms (Guilan province, Iran) were examined for the presence of 12 virulence genes (hlyF, iroN, iss, iutA, ompT, astA, tra, sfa-foc, papC, fimH, cvi/cva, and Tia) using polymerase chain reaction (PCR). Antimicrobial susceptibility assessment was performed for the isolates using disc diffusion method against 19 antibiotics.
Findings: The fimH, iut, tra, iss, iroN, hly, and ompT genes were detected as the most prevalent genes among colibacillosis-causing isolates (more than 70%), while sfa-foc (S fimbriae and F1C fimbriae subunits) had the lowest frequency among colibacillosis-causing E. coli isolates (3.28%).
Conclusion: Virulence-associated genes were frequently detected in avian pathogenic E. coli strains. These findings could help better understand the pathogenicity potential of E. coli in poultry. Preventative measures are necessary to reduce food and environmental contamination with avian E. coli strains.

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 At the beginning of the sixties, Bushehr was the governorate of all the ports and islands of the Persian Gulf, which was politically under the jurisdiction of Fars province. The ports and islands of the Persian Gulf and its coastal areas in the past periods always had a limited population and a low population density due to the political and social conditions as well as its climatic condition. At the beginning of the sixties, with the implementation of agrarian reforms in the country, conditions were created that allowed the rural population to move and migrate more. In this research, an attempt is made to investigate the conditions that accelerated the process of rural migration in the governorate in the 1960s and 1970s. The present research method is descriptive-analytical based on historical documents and sources. According to the findings of the research, in addition to the implementation of land reforms, which freed a large part of the labor force in rural areas, and this additional force went to the city to find work, the climatic and atmospheric conditions of the region and the excessive deprivation of rural areas are also among the reasons. The main expansion of rural migration was in the Governorate of Ports and Islands. This region, which had the lowest urbanization rate in the country in the years before the sixties, faced a high urbanization growth in the following years.

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With the arrival of Muslims in Iran, a new chapter in the social and religious history of the Iranian people began. However, the arrival of Islam in Iran faced many challenges and resistances in various regions. Among the various regions, Persia was one of the regions that showed resistance and practically became the base for the protection of the former religion; Meanwhile, due to the establishment of a Zoroastrian local government, Kazerun was able to maintain the cohesion of its Zoroastrian community until the early fifth century AH. Given the various pressures on Zoroastrian communities by newcomers and neo-Muslims, understanding the continuity of the independent Zoroastrian community in southwestern Persia until the early fifth century AH seems necessary. This research seeks to examine the contexts of continuity and evolution of the Zoroastrian community of Kazerun during the first centuries of Islam. The present research has been done by descriptive-analytical method and relying on library resources.
The findings of this study show that despite the excessive pressure of the new rulers of the Zoroastrian community of Kazerun and the imposition of various restrictions, they managed to survive by maintaining coherence in their structure and actions and having a Zoroastrian ruler, but from the late fourth century and In the early fifth century, with the emergence of many conflicts with the Morshidiyya sect of Kazerun, they faced problems in the management of society, and finally, by migrating to mountainous and rural areas, they continued their life in a different style and way.

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This study aims at ascertaining a framework that would account for the Persian data. We scrutinize all data occurring in the selected corpus, and describe how they usually work on the basis of the two following variables: power and intimacy. According to our investigation, the use of terms of address in Persian is affected by age, sex, occupation, ideology, political and social position of the interlocutors. These variables can be stated as a result of the investigation of older material – such as qualitative analysis of observations followed by unobtrusive note taking of contemporary use, a corpus of several plays, travel accounts, interviews, TV, radio and careful observation terms used to address today. The above-mentioned variables indicate a strong relationship between social structures and address terms in Persian.

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In this study, the effect of adding different percentages of malt extract (1.5, 3, 4.5, 6 % v/v) to apple juice on the survival of the probiotic bacterium Lactobacillus plantarum during four weeks of storage at 4 ° C was investigated. In addition, in order to evaluate the physicochemical and sensory properties of the produced juices, pH, acidity, brix, total sugar and sensory evaluation tests were performed. The results showed that with increasing the concentration of malt extract in apple juice, the amount of acidity, brix, total sugar increased and the pH decreased. In addition, the highest acidity and the lowest pH belonged to the apple juice sample containing 6% (v / v) of malt extract. Also, the addition of malt extract improve survival of probiotic bacterium and increased its population in apple juice samples compared to the control sample. Moreover, no significant difference was observed between the populations of L. plantarum probiotic bacteria in apple juice samples containing malt extract at the end of cold storage. In the sensory evaluation test, the highest overall acceptance score by the panelist members was assigned to apple juice samples containing 1.5 and 3% of malt extract, respectively. According to the results of adding malt extract on the properties of probiotic apple juice, the produced juice in this study can be a good alternative to juices available in the market with functional properties.
 

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  Among the three basic phenomena of fertility, mortality and migration, which leads to demographic changes, the present paper tries to analyze the mortality among the ideas of Avicenna, a Persian physician and philosopher(370-428 AD). The way to advance the study and achieve the desired objectives, was adopted by using documental-analytical method. The results showed that Ibn Sina's book "The Law", in addition to discussions about life and life expectancy, and addressing its causes, such as in the area of public health, the health of mothers, children and the elderly, also directs one’s attention to the phenomenon of death; is shown for example, fetal death during pregnancy, maternal death during pregnancy, and childbirth are talked about and described quite extensively, and seen as a medical specialty.      

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Childbearing is a very important concept in contemporary demographic theories, referred to as fertility. In order to describe and understand this concept, the current article has taken into account the views and ideas of Muslim thinkers such as Al-Farabi, Miskawayh, Al-Ma'arri, Ibn Sina, Khaje Nasir al-Din, and Ibn Khaldun, using the attributional method. This reseacrh is important as today’s university system of Iran is based on the principles of Islamic law hence; there is need for indigenous knowledge in all fields of humanities, including demography. The findings of the study show that all the thinkers have had paid attention to the issue of reproduction and its related forces. The importance of reproduction or generational reproduction in their view has been so importnat that they not only introduced fertility as a vital feature of women but also explained the first and foremost purpose of marriage as the human generational reproduction. They used religious verses and traditions to substantiate their views. However, Al-Ma'arri is an exception as he recommends men to abstain from marriage and childbearing. The analysis of the findings and results shows that the Muslim thinkers, despite discussing about childbearing and related phenomenon, have not provided figures in this regar and rather expressed their ideas theoretically. Of course, this should not be seen as a sign of the weaknesses of those great thinkers, but that was probably due to a limitation on statistical data in the past.

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Attention to child and childhood has existed throughout history as pre-sociological paradigms. The present study tries to retrospectively examine Ghazali’s views on child and childhood, and measure the importance he gave to this issue. Al-Ghazali is one of the well-known thinkers of the fifth century AH, whose views on education and divine-human thought have greatly influenced the future. This study is conducted using the documentary method. The studied documents included primary and secondary sources. The results show that Ghazali, while paying attention to child and childhood, considers the nature of children to be pure and innocent. These children are understood under the banner of two institutions of family and "high school" (school), both of which are responsible for raising and educating children. The child has characteristics such as weakness of intellect, imitation and imperfection, which are placed in the process of socialization on the one hand by adults with the power of education and discipline. Al-Ghazali considers the beginning of childhood from the time of sperm formation to the end of puberty for girls and the age of sixteen for boys, from which they can enter into married life, in other words, the world of adulthood. The findings led the researcher to conclude that al-Ghazali, despite his use of the concept of "child," focused on children-boys rather than children-girls.