14 research outputs found

    Area dependent searching efficiency of Scymnus syriacus (Col.: Coccinellidae) feeding on Aphis craccivora (Hem.: Aphididae)

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    Searching efficiency is a key parameter of functional response which is in turn the major components in the selection of predators and parasitoids for biological control. Searching efficiency of Scymnus syriacus Mulsant feeding on Aphis craccivora Koch was determined at five different experimental arenas (i.e. 195, 247, 304, 385 and 650 cm2) on broad bean (Vicia fabae L.). To do this, functional response of the predator to different densities (i.e., 10, 20, 30, 40 and 60) of the third instar nymphs of A. craccivora was studied. At each experiment, one 48-h.-old female was introduced to the aphid density in a container (as an experimental arena) and replicated five times. The experiments were carried out at 25Ë Â± 1C, 65 ± 5% RH and a photoperiod of 16L: 8D h. Using the logistic regression, a type III functional response was determined for S. syriacus in the entire five experimental arenas. Searching efficiency was found to be area dependent as it decreased as the area of experimental arena increased. The maximum expected predation rates (T/Th) were 48.56, 42.44, 40.77, 38.09 and 34.88 in the five experimental arenas, respectively. The area searched as a function of prey density indicated that as prey density increased, the area searched by the predator decreased. It is concluded that the size of searching area and prey density, both influence foraging behavior of S. syriacus

    Comparison of the Efficiency of Traditional and Industrial Milk Production Units in Khuzestan Province

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    One of the most important measures, in order to increase animal products and reduce imports, is the industrialization of animal husbandry units, specially the dairy cattle. The condition of milk production would be improved by this industrialization, which is in the direction of increasing the efficiency of milk production units. The purpose of this study is calculate , the efficiency of the traditional and industrial milk production units of Khuzestan province in 2011. The method of research was causal comparative. Data envelope analysis, in both forms of constant and variable return to scale, was used to calculate the types of efficiency. The needed information of industrial and traditional cattle houses was gained using capitation and random sampling from 384 production units, respectively. According to the results, the rate of total efficiency among the milk producers of traditional and industrial milk production units of Khuzestan is significantly different. In addition, the size of cattle house, manger`s level of education and experience, having a secondary job, animal`s race, and the production method are factors affecting the efficiency of units

    Urine macrophage migration inhibitory factor in pediatric systemic lupus erythematosus

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    We reported a series of ten patients with lupus nephritis (five patients in the relapse phase and five in the remission phase) and measured the macrophage migration inhibitory factor (MIF), an important pro-inflammatory cytokine with probable role in the pathogenesis of many inflammatory diseases, in their urine samples. MIF/creatinine (Cr) ratio directly correlated with disease activity and it does not have any significant difference between inactive disease and normal ones. We found that the urine MIF/Cr ratio not only differentiates active disease from inactive disease and normal ones but also correlates with the activity indices of renal pathology. © Clinical Rheumatology 2007

    Identify and analyze the opportunities and threats of social networks for shahid Beheshti University students

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    Due to the growth of information and communication technology in societies Especially among students, the use of these technologies has become as part of regular working people. Social networks as one of the most important and widely in cyberspace which is Used by many people in various fields. application of social network by students as young and educated population is important.In this regard, this study aimed to investigate and identify the opportunities and threats for shahid Beheshti University students in social network. This study aims to develop a practical and descriptive methodology. Information obtained from the questionnaires using SPSS statistical analysis software in two parts: descriptive and inferential statistics were analyzed.The results indicate that five variables related to social networking opportunities, including e-learning, leisure, organized social groups, the possibility of dialogue and culture, as well as five variables related to social networking threats, including transfer value unethical, abusive, spreading false information, internet & Communications destructive addiction, has a significant positive effect on students

    Investigating effectiveness of clandestine advertisement and organizational strategy in brand management

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    This investigation tries to examine correlation between clandestine advertisement and organizational strategy in brand management via available sources and by using a field study. In fact, it intends to raise the question “Are clandestine advertisement and organizational strategy effective in management of products brands?” This is an applied and descriptive-approaching study. The study chooses a sample of 171 regular customers who do their day-to-day banking business activities through an Iranian bank named Sepah bank in city of Tehran, Iran. Using structural equation modeling, the study confirms a positive and meaningful relationship between clandestine advertisement and organizational strategy in brand management
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