3,454 research outputs found
A comparative study on the functional response of Wolbachia-infected and uninfected forms of the parasitoid wasp Trichogramma brassicae
Trichogramma species (Hymenoptera: Trichogrammatidae) are haplo-diploid egg parasitoids that are frequently used as biological control agents against lepidopteran pests. These wasps display two reproductive modes, including arrhenotoky (bisexuality) and thelytoky (unisexuality). Thelytokous forms are often associated with the presence of endosymbiotic Wolbachia bacteria. The use of thelytokous wasps has long been considered as a way to enhance the efficacy of biological control. The present study investigates the potential of a thelytokous Wolbachiainfected and an arrhenotokous uninfected Trichogramma brassicae Bezdenko strain as inundative biocontrol agents by evaluating their functional response towards different egg densities of the factitious host, the Angoumois grain moth, Sitotroga cerealella (Olivier) (Lepidoptera: Gelechiidae). The results revealed a type II functional response for both strains in which parasitism efficiency decreases with host egg density because of an increasing host handling time. A model with an indicator variable was used to compare the parameters of Holling’s disc equation in different data sets. It was demonstrated that the two strains did not differ in host attack rate. However, the Wolbachia-infected strain did have an increased host handling time when compared to the bisexual strain. Some applied aspects of the findings are discusse
Nodular Fasciitis of Neck in Childhood.
Nodular fasciitis, is a benign, pseudo sarcomatous proliferative lesion of the soft tissue, which is frequently misinterpreted as sarcoma, both clinically and microscopically. It is a reactive lesion composed of fibroblasts/myofibroblasts and most commonly found in extremities and trunk. NF has been described in the head and neck region in 10-20% of cases. Many pathologists do not consider NF in the differential diagnosis of soft tissue masses arising in the Head neck region. NF that occurs in otherwise healthy individuals usually presents with a history of rapid growth, and is commonly found in the upper extremities and on the chest and trunk. The importance of otolaryngologists being aware of the existence of this entity in this area of the body is stressed. It has a confirmed perfectly benign clinical course, and simple excision, as tissue-sparing as possible, is the treatment of choice. A case of NF over the neck in a 05-year-old female not associated with trauma who presented with a localized mass over her left neck is presented
Effects of information technology on the business
Information Technology develops extremely fast and never stops moving because we need this important and strategic technology. The article is about effects of Information Technology on Business and help of IT to prevent products smuggling, and in this scientific article we tried to introduce big achievements which are ideal prevention and security solutions that IT delivered recently and it had a very big effect of Business World.В современном мире, информатизация, как процесс, затрагивает все сферы деятельности государства как единой системы. Особо важно иметь весь срез данных при стратегическом планировании любого уровня, которое является одной из составляющих управленческой деятельности. В сфере большого, среднего и малого бизнеса информационные технологии переводят деятельность предприятий на качественно иной уровень. В статье рассматриваются вопросы, связанные с применением информационных технологий для предотвращения проникновения на рынок контрафактной продукции
The use of fuzzy real option valuation method to rank Giga Investment Projects on Iran's natural gas reserves
Giga investments are exposed to numerous systematic and unsystematic (or specific) risks that significantly influence their feasibility and value. In addition to the conventional issues and complexities in evaluating investment projects, factors such as long construction time, high amount of capital required and irreversibility of investment, increase uncertainty of cash flows in these types of projects. As a consequence, decision makers are usually not satisfied with the results of the most popular valuation methodology – discounted cash flow analysis – in valuation of Giga investments. The most promising methodology of valuing flexibility in such investment projects is the real options valuation which quantifies the value of embedded flexibilities through option pricing techniques.In this paper, fuzzy real options valuation techniques are used to rank Giga project proposals faced in Iran's gas industry. To this end, different scenarios of project payoff and future uncertainties are quantified, using fuzzy numbers based on findings from earlier real option valuation methods.Keywords: Giga Investment, Fuzzy Pay Off, Real options valuation, Natural Gas, Ira
Group A �-hemolytic streptococcal infection in children and the resultant neuro-psychiatric disorder; a cross sectional study; Tehran, Iran
Introduction: Group A Beta-Hemolytic Streptococcus (GABHS) can induce PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection). GABHS is the most important and common bacterial cause of acute pharyngitis in Iranian children. We studied the role of GABHS (anti-streptococcal antibodies) in suspected cases of PANDAS in a cross sectional studies. Methods: Across sectional study was done in 2 pediatric psychiatric/and neurologic clinics in Tehran (Rasul Akram and Aliasghar Hospital) during 2008-2010. We studied serum antistreptococcal antibodies (anti streptolysin O, anti Deoxyribonuclease B, and anti-streptokinase (ABcam-ELISA, USA) in 76 cases with psychiatric manifestation (OCD, ADHD) in compare with 39 healthy controls. These antibodies were studied in 53 cases with movement disorders (Tic/Tourette syndrome) in compare with 76 healthy controls. Sensitivity, specificity and positive predictive value of tests were calculated. Results: In movement disorders ASOT, Anti-DNase and Anti streptokinase was significantly higher than controls (p 200IU/ml) had 75 sensitivity; 84 specificity and 80 PPV; Antistreptokinase (cut off level> 332 IU/ml) had 34 sensitivity; 85 specificity, and 72 PPV; Anti-DNase (cut off level> 140IU/ml) had 70 sensitivity; 99 specificity and PPV 90 for differentiating the group. ASOT, Anti-DNase and Anti streptokinase titer was significantly higher than controls (p<0.0001, p=0.000, p<0.0001). ASOT had 90 sensitivity; 82 specificity, PPV 92; Anti streptokinase: 82 sensitivity; 82 specificity, PPV 95; Anti DNase: 92 sensitivity; 82 specificity, PPV 92 for differentiation the cases from normal controls. Discussion: These findings support that a post infectious immune mechanism to GABHS may play a role in the pathogenesis of PANDAS in our children. A combination of throat culture, rapid antigen detection test, and serologic testing for GABHS is required to achieve maximum sensitivity and specificity for diagnosis. We prefer to use antibiotic prophylaxis in PANDAS cases for preventing recurrent streptococcal infections. Ongoing research is needed for identifying optimum diagnostic, prevention and therapeutic approach especially, aggressive treatment (intravenous immunoglobulin, plasmaphresis)
Basic data report on the turbulent spread of heat & matter
CER71-72RSM-9.August 1971.Includes bibliographical references (page 75).United States Dept. of Interior Geological Survey, Water Resources Division in cooperation with the United States Environmental Protection Agency, National Thermal Pollution Research Program.The purpose of this report is to present the results of an investigation of the turbulent transport properties of heated and salt water jets in an open channel flow. The data were taken cooperatively by the U.S. Geological Survey and the Environmental Protection Agency. The data include measurement of the turbulence characteristics, longitudinal dispersion, and vertical and lateral turbulent diffusion. Three different boundary roughnesses were used in the investigation. The turbulence data includes the intensity of turbulence, Eulerian time scales, autocorrelation function distributions, space correlation distributions in the vertical and horizontal directions and space-time correlation function distributions in the longitudinal direction. Vertical and lateral turbulent diffusion data were obtained downstream from jets of three diameters, at four different jet strengths. Two tracer fluids, heated water and a neutrally buoyant salt solution were used. Only basic data are reported here. The extensive analysis of these results will be the subject of a future publication
First Detection of Nosema ceranae, a Microsporidian Protozoa of European Honeybees (Apis mellifera) In Iran
Background: Nosemosis of European honey bee (Apis mellifera) is present in bee colonies worldwide. Until recently, Nosema apis had been regarded as the causative agent of the disease, that causes heavy economic losses in apicultures. Nosema ceranae is an emerging microsporidian parasite of European honeybees, A. mellifera, but its distribution is not well known. Previously, nosemosis in honeybees in Iran was attributed exclusively to N. apis.Methods: Six Nosema positive samples (determined from light microscopy of spores) of adult worker bees from one province of Iran (Savadkouh- Mazandaran, northern Iran) were tested to determine Nosema species using previously- developed PCR primers of the 16 S rRNA gene. As it is difficult to distinguish N. ceranae and N. apis morphologically, a PCR assay based on 16 S ribosomal RNA has been used to differentiate N. apis and N. ceranae.Results: Only N. ceranae was found in all samples, indicating that this species present in Iran apiaries.Conclusion: This is the first report of N. ceranae in colonies of A. mellifera in Iran. It seems that intensive surveys are needed to determine the distribution and prevalence of N. ceranae in different regions of Iran
Dependence of Carbon Nanotube Field Effect Transistors Performance on Doping Level of Channel at Different Diameters: On/off current ratio
Choosing a suitable doping level of channel relevant to channel diameter is
considered for determining the carbon nanotube field effect transistors'
performance which seem to be the best substitute of current transistor
technology. For low diameter values of channel the ratio of on/off current
declines by increasing the doping level. But for higher diameter values there
is an optimum point of doping level in obtaining the highest on/off current
ratio. For further verification, the variations of performance are justified by
electron distribution function's changes on energy band diagram of these
devices. The results are compared at two different gate fields.Comment: 9 double spaced pages, 4 figures, published in applied physics
letters, along with the terms of the American Institute of Physics Transfer
of Copyright Agreement at first pag
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