A computational framework for thermal coupling in hybrid fire simulation

In structural fire engineering, it is crucial to estimate the global structural behavior in a realistic scheme. This necessity arises from the reason that the single element testing doesn’t represent the global behavior of the structure correctly due to the possible load redistribution into alternative load paths and change of static systems in case of global fire. Therefore, hybrid simulation method can be accounted as a key method, which fulfills the possibility of study of the global structural behavior in structure with coupling the numerical simulation and experimental testing. In this method, the numerical simulation procedure of the whole structure is coupled and controlled with the outcomes of the experiment performed on a single part of the structure, which is critical or difficult to study numerically. So far, several attempts have been made to study hybrid fire simulation. There, however, exist severe shortcomings in so-far research: - the correct consideration of the stiffness and material properties for the heated element and their degradation during fire exposure, - retaining the compatibility and the equilibrium between the substructures, - the automatic real-time interaction between the substructures and also - realistic consideration of the thermal coupling between substructures with regard to the transfer of the heat from fire exposed component to adjacent elements. In hybrid fire simulation, the thermo-mechanical coupling can be studied realistically, when the heat exposed to the single compartment, its transfer to the adjacent substructures and the effect of two latter on the mechanical response of the structure is considered. In the current paper, this purpose is studied on a steel structure benchmark with two different approaches: sequentially-coupled thermal-stress analysis and fully-coupled thermal-stress analysis. Here, the mathematical and mechanical aspects of each approach and their difference regarding the response of the structure will be investigated. Also, their application in the hybrid fire simulation and the importance of the real-time issue in these approaches are outlined. In this paper, the numerical model of the intended benchmark which interacts automatically with another numerical model, representing the experimental substructure exposed to fire is studied. Therefore, the implementation of hybrid fire simulation and different aspects of the thermal coupling including the existence of heat transfer and mechanical and thermal properties will be discussed

High infection of Anaplasma and Ehrlichia spp. among tick species collected from different geographical locations of Iran

Objective: To ascertain the prevalence of the Anaplasma/Ehrlichia infections in tick population within four provinces of Iran. Methods: A total of 384 tick specimens were collected from domestic animals inhabiting in four provinces (East Azerbaijan, Gilan, South Khorasan and Yazd). Specimens were identified based on morphological analysis. The detection of Anaplasma spp./Ehrlichia spp. within tick samples was carried out by nested PCR amplification of the 16S ribosomal RNA gene accompanied by DNA sequencing and analysis for verification. Results: A total of 10 tick species were identified as follows: Ornithodoros lahorensis (O. lahorensis) (44.8), Hyalomma dromedarii (15.6), Dermacentor marginatus (13.5), Hyalomma anatolicum (11.2), Hyalomma asiaticum (5.7), Hyalomma marginatum (4.9), Rhipicephalus sanguineus (2.3), Hyalomma detritum (1.0), Dermacentor niveus (0.5) and Argas persicus (0.3). The percentage distribution of Anaplasma/Ehrlichia was 55.5 (213) across 384 studied ticks. Conclusions: To the best of our knowledge, this is the first report of Anaplasma ovis infection in O. lahorensis in Iran. We also conjecture the prevalence of Ehrlichia spp. in Yazd Province based on sequencing results; also, it is suggested that O. lahorensis is a potential vector in the studied area. This survey highlights the importance of Argasidae family to verify and correlate their threat in causing anaplasmosis and other diseases in animals. © 2016 by the Asian Pacific Journal of Tropical Disease

Laboratory investigation of the impact of air pollution on partial discharge inception voltage of insulators in a specific region

Studying the discharge characteristics of transmission line insulators in the presence of pollution, particularly when the contaminated layer is wet by rain, fog or condensation, is necessary for selecting the proper insulation. Therefore, identifying the major air pollutants as well as the most effective ones on the discharge performance of outdoor insulators is mandatory. A systematic approach has been proposed to evaluate the impact of dominant air pollutants of an area on partial discharge (P.D) inception voltage of specimen insulators. Based on the suggested method, determining the pollution constituents, defining the dominant pollutant of the area, finding the most commonly used insulators for medium and above distribution voltages within the geographical boundaries of the Central Province of Iran, as well as examining the effect of dominant air pollutant of the region on partial discharge inception voltage of designated insulators by laboratory measurements, are the necessary steps toward a comprehensive study of the subject

Presentation of an Algorithm for Secure Data Transmission based on Optimal Route Selection during Electromagnetic Interference Occurrence

This paper proposes a comprehensive algorithm for secure data transmission via communication conductors considering route optimization, shielding and data authentication. Using of appropriate coding method causes more efficiency for suggested algorithm during electromagnetic field attack occurrence. In this paper, MOM simulation via FIKO software is done for field distribution. Due to critical situation of malfunctioning of data transferring, appropriate shield is designed and examined by shielding effectiveness (SE) criterion resulted of MOM simulation; finally to achieve reliability of data security, MAC hash function is used for space with field attack probability, turbo code is employed

Role of endogenous oxytocin in cardiac ischemic preconditioning

Background: The aim of the present study is to assess the role of endogenous oxytocin (OT) in cardioprotective effects of ischemic preconditioning (IPC) in anesthetized rat. Materials and methods: Animals were divided into five groups: 1) ischemia-reperfusion (IR); (n= 6), hearts were subjected to 25 min regional ischemia and 60 min reperfusion, 2) OT; (n= 6), oxytocin was administered (0.03. μg/kg i.p) 10 min prior to ischemia, 3) IPC; (n= 7), IPC was induced via a 5 min regional ischemia followed by 5 min of reperfusion before IR, 4) IPC. +. ATO (Atosiban); (n= 6), atosiban (1.5. μg/kg i.p) was used as OT receptor selective antagonist in the beginning of IPC and 5) IR. +. ATO; (n= 6), atosiban was injected 10 min prior to ischemia-reperfusion. Results: In our experiment, Infarct size was decreased significantly in OT and IPC groups compared to IR (23 ± 1.5% and 19 ± 0.6% vs 45 ± 2.9% in IR group, P < 0.05). Administration of atosiban in IPC. +. ATO group increased infarct size to 39 ± 0.9% in comparison with OT and IPC groups (P<0.05). The use of OT and IPC prior to ischemia significantly declined ventricular arrhythmias severity in compared to IR group (1.2±0.4 and 1 ±0.5 respectively, vs 4±0.4 in IR group, P<0.05). Blockade of OT receptor by atosiban abolished the cardiopreconditioning effects of IPC. Conclusion: This study shows that, in part, the cardioprotective effects of IPC can be induced by endogenous OT. © 2010 Elsevier B.V

Vectors of Crimean Congo Hemorrhagic Fever virus in Iran

Background: Ticks are important vectors and reservoirs of Crimean Congo Hemorrhagic Fever (CCHF) virus. Human beings may be infected whenever the normal life cycle of the infected ticks on non- human vertebrate hosts is interrupted by the undesirable presence of humans in the cycle. A total of 26 species of Argasid and Ixodid ticks have been recorded in Iran; including nine Hyalomma, two Rhipicephalus, two Dermacentor, five Haemaphysalis, two Boophilus, one Ixodes and two Argas as well as three Ornithodoros species as blood sucking ectoparasites of livestock and poultries. The present paper reviews tick vectors of CCHF virus in Iran, focusing on the role of ticks in different provinces of Iran using reverse transcription polymerase chain reaction (RT-PCR) assay. Methods: During ten years study, 1054 tick specimens; including two species of Argasidae and 17 species of Ixodidae were examined for their infection to CCHF virus genome. The output of all studies as well as related publications were discussed in the current paper. Results: The results show that Rhipicephalus sanguineus, Hyalomma marginatum, H. anatolicum, H. asiaticum and H. dromedarii were known as the most frequent species which were positive for CCHF virus. Conclusion: The status of ticks which were positive for CCHF virus revealed that unlike the most common idea that Hyalomma species are the most important vectors of CCHF virus, other ticks including Rhipicephalus, Haemaphysalis and Dermacentor can be reservoir of this virus; thus, considering geographical distribution, type of host and environmental conditions, different tick control measurements should be carried out in areas with high incidence of CCHF disease

Regional Assessment of Soybean Brown Stem Rot, Phytophthora sojae, and Heterodera glycines Using Area-Frame Sampling: Prevalence and Effects of Tillage

The prevalence of brown stem rot (caused by Phialophora gregata), Heterodera glycines, and Phytophthora sojae in the north central United States was investigated during the fall of 1995 and 1996. Soybean fields were randomly selected using an area-frame sampling design in collaboration with the National Agricultural Statistics Service. Soil and soybean stem samples, along with tillage information, were collected from 1,462 fields in Illinois, Iowa, Minnesota, Missouri, and Ohio. An additional 275 soil samples collected from Indiana were assessed for H. glycines. For each field, the incidence and prevalence of brown stem rot was assessed in 20 soybean stem pieces. The prevalence and recovery (expressed as the percentage of leaf disks colonized) of P. sojae and the prevalence and population densities of H. glycines were determined from the soil samples. The prevalence of brown stem rot ranged from 28% in Missouri to 73% in Illinois; 68 and 72% of the fields in Minnesota and Iowa, respectively, showed symptomatic samples. The incidence of brown stem rot was greater in conservation-till than in conventional-till fields in all states except Minnesota, which had few no-till fields. P. sojae was detected in two-thirds of the soybean fields in Ohio and Minnesota, whereas 63, 55, and 41% of the fields in Iowa, Missouri, and Illinois, respectively, were infested with the pathogen. The recovery rates of P. sojae were significantly greater (P ≤ 0.05) in conservation-till than in conventional-till fields in all states except Iowa. H. glycines was detected in 83% of the soybean fields in Illinois, 74% in Iowa, 71% in Missouri, 60% in Ohio, 54% in Minnesota, and 47% in Indiana. Both the prevalence and population densities of H. glycines were consistently greater in tilled than in no-till fields in all states for which tillage information was available

Content analysis of secondary school chemistry textbooks based on components of resistance economy: Shannon Entropy Methodod

Background and Objectives:The present study aims to analyze the content of second grade chemistry textbooks based on the emphasis on the goals of resistance economy. Methods: The research method in this study was descriptive content analysis. In this study, after collecting quantitative data, Shannon entropy technique was used for anarysis. The statistical population of this study formed the content of all secondary high school chemistry textbooks. The sampling method in this study was census; Therefore, all second grade chemistry textbooks were analyzed. The registration unit in this study was the subject. In this study, the frequency of components and themes of resistance economy in chemistry curricula were examined. Findings: The findings of the content analysis showed that in secondary high school chemistry books, the most attention was paid to the goals of resistance economy in the field of consumption the field of skills and the field of production attitude. Conclusion: From the present study, it can be concluded that in the second grade chemistry textbooks, very little attention has been paid to the goals of the resistance economy. Also, in secondary school chemistry curricula, little attention has been paid to the goals and components of the resistance economy and the amount of attention to the goals of the resistance economy do not have a normal distribution and only some components of the resistance economy in the second secondary school (three dimensions and three areas) are consi dered

Regression of nonalcoholic fatty liver disease with zinc and selenium co-supplementation after disease progression in rats

Background: Studies have shown that zinc and selenium deficiency is common in nonalcoholic fatty liver disease (NAFLD). However, the effects of zinc and selenium co-supplementation before and/or after disease progression on NAFLD are not clear enough. The aim of this study was to compare the effects of zinc and selenium co-supplementation before and/or after disease progression on NAFLD prognosis. Methods: Forty male Sprague�Dawley rats (197±4 g) were randomly assigned to 4 dietary groups: normal-fat diet (NFD; receiving 9 of calories as fat), high-fat diet (HFD; receiving 82 of calories as fat), supplementation before disease progression (S+HFD), and supplementation after disease progression (HFD+S). The diets were implemented over a 20-week period in all the groups. Biochemical and histologic parameters were compared between the 4 groups, and betweengroup comparisons were also carried out. Results: There were significant differences in the average food dietary intake (P<0.001), weight (P<0.001), fasting blood sugar (P=0.005), triglyceride (P<0.001), total cholesterol (P<0.001), low-density lipoprotein cholesterol (P=0.002), high-density lipoprotein cholesterol (P=0.001), alanine aminotransferase (P<0.001), and aspartate aminotransferase (P<0.001) between the 4 dietary groups. Serum triglyceride and total cholesterol were significantly lower in the HFD+S Group than in the S+HFD Group (P<0.001 and P=0.003, respectively). Fat accumulation was significantly reduced in the HFD+S Group (P<0.001). Conclusion: Zinc and selenium co-supplementation after disease progression improved biochemical and histologic parameters in an experimental model of NAFLD. © 2018, Shiraz University of Medical Sciences. All rights reserved