Work-related stress dimensions among a subsidiary company workers of Iranian oil refining and distribution company

Introduction Work-related stress and its causes are among the most important issues which can seriously challenge organizational efficiency and employees' health. Different occupational environments and groups have different levels of job stress. The present study aimed to investigate relationships between job stress and its dimensions with three occupational groups (administrative, administrative-operational, and operational) among a subsidiary company workers of Iranian Oil Refining and Distribution Company. Methods The present study had descriptive-analytical and cross-sectional type and was conducted among 468 out of 503 employees (with entry condition of a year of work experience as well as an official and contractual membership) volunteered to participate in research. Data collection tools included demographic questions and job stress questionnaire as well as human resource department information to determine occupational group of employees. Descriptive statistics, statistical tests, Independent test, and one-way ANOVA in addition to SPSS 21 software were used for data analysis. Results There were significant relationships between age, education levels, work experience and smoking with mean score of job stress (P-value 0.05). Conclusions Exposure to different occupational harmful agents, facing with different safety risks, being far from family, heavy workload, and uncertain employee roles have significantly increased job stress in both operational and executive occupation groups compared to other two occupational groups; hence, there is a positive correlation between high job stress and operational jobs

Malicious User Attack in Cognitive Radio Networks

Signal detection in cognitive radio network (CRN) is influenced by several factors. One of them is malicious user that emulate primary user (PU) signal. Emulation of PU signal causes detection error. This paper investigates the impact of malicious user attack to PU signal detection. A number of malicious users are randomly deployed around secondary user (SU) at a certain distance. They attempt to attack primary signal detection that is transmitted from 100 km to SU receiver. Then, the received signal power at secondary receiver and the performance of probability of false alarm and probability of miss detection under two hypothesis of Neyman Pearson criterion are studied. The derived results show that a number of malicious users has a significant impact to the performance of received power at SU and detection error rate

Advantages and Disadvantages of Health Care Accreditation Mod­els

Background: This systematic review seeks to define the general advantages and disadvantagesof accreditation programs to assist in choosing the most appropriate approach.Method: Systematic search of SID, Ovid Medline & PubMed databases was conducted by thekeywords of accreditation, hospital, medical practice, clinic, accreditation models, health careand Persian meanings. From 2379 initial articles, 83 articles met the full inclusion criteria.From initial analysis, 23 attributes were identified which appeared to define advantages anddisadvantages of different accreditation approaches and the available systems were comparedon these.Results: Six systems were identified in the international literature including the JCAHO fromUSA, the Canadian program of CCHSA, and the accreditation programs of UK, Australia,New Zealand and France. The main distinguishing attributes among them were: qualityimprovement, patient and staff safety, improving health services integration, public’s confidence,effectiveness and efficiency of health services, innovation, influence global standards,information management, breadth of activity, history, effective relationship with stakeholders,agreement with AGIL attributes and independence from government.Conclusion: Based on 23 attributes of comprehensive accreditation systems we have definedfrom a systematic review, the JCAHO accreditation program of USA and then CCHSA ofCanada offered the most comprehensive systems with the least disadvantages. Other programssuch as the ACHS of Australia, ANAES of France, QHNZ of New Zealand and UK accreditationprograms were fairly comparable according to these criteria. However the decision forany country or health system should be based on an assessment weighing up their specificobjectives and needs

An in vitro Comparative study upon the Hemolytic, Thrombogenic, Coagulation parameters and Stability properties of the Hemiscorpius lepturus Venom

Hemiscorpius lepturus belonging to Hemiscorpiidae family is the most venomous of all types of scorpion existing in south west of Iran causing hemoglobinuria and dermal lesions by envenomation. We compare the hemolytic pattern upon time in different domestic animals upon time according to their different sphingomyelin contents. In addition other in vitro hematologic parameters, platelet lysis, coagulation changes and finally preservative factors (temperature, pH, protases) are discussed. The hemolytic activity was inhibited significantly by heating at 100 °C for 60 minutes (26%) and reached 38% via incubation with papain (10U/ml) while retained over a pH range of 4-11. Horses and sheep have the lower (61%) and upper (100%) rate of hemolysis. Calcium and magnesium ions could increase rate of hemolysis and EDTA solution had significantly decresing effect. The venom significantly changed in vitro coagulation factors (PT and APTT) from base line levels and had no effect on platelet lysis. It seems that our venom belongs to metalloproteinases due to potentiation effects of bivalent cations (calcium and magnesium) and ghost cell formation in our study indicatiing hemoglobin efflux

Antiviral activity of Holothuria sp. a sea cucumber against herpes simplex virus type 1 (HSV-1)

BACKGROUND: Finding the new bioactive compounds with antiviral activity from the natural resources are in interest of many drug discovery scientists. Sea cucumber is among the marine organisms a traditional food item in Asia with different applications in traditional medicine. METHODS: In current study, a cold water extract of the Holothuria sp, one type Persian Gulf’s sea cucumber was evaluated for its antiviral effects against KOS strain of Herpes Simplex Virus tyoe 1 (HSV-1) in cell culture. The half maximal inhibitory concentration (IC50) values were calculated for anti-adsorption activity and intracellular antiviral activity of the crude extract separately. RESULTS: The extract exhibited antiviral activity not only against the virus adsorption to the cells, but also on virus intracellular replication.The CC50 for sea cucumber extract was 32.57 mg/ml. The IC50 values for the inhibition of the virus adsorption to the cells and virus intracellular replication were 120.2 and 189.9 μg/ml respectively. Selectivity index (SI) value for anti-adsorption activity was 189 while that value for the extract’s intracellular antiviral activity was 172. CONCLUSIONS: The results showed that Holothuria sp, water extract has remarkable antiviral effect against HSV-1 in cell culture and it is crucial to investigate the mechanism(s) of action of extract. Moreover, identification of the effective compound(s) within the extract would be necessary for future studies towards developing the new natural antiviral agent against HSV-1

Investigation of the Impacts of Social Capital on Organizational Entrepreneurship in Tehran Municipality

Entrepreneurship is the symbol of endeavor and success in business, and entrepreneurs play a crucial role in economic and social development of communities. Since Organizational Entrepreneurship (OE) contribute to earning stable finance required for administration of urban affairs, it is very important in the case of municipalities. For this reason, this study aims to investigate the role of social capital (SC) in the development of entrepreneurship in Tehran municipality. Research method was descriptive and non-experimental, and required data were collected through 204 questionnaires distributed among managers and experts of the organization. Stratified sampling was used, in which 37 managers and 167 experts participated. Number of male participants was 147, and number of female participants was 57. The mean age of participants was 41 years, and its standard deviation was 0.765. In order to test the research hypothesis, structural equation modeling (SEM) was used. The results of the study showed that social capital and its three dimensions (Cognitive, Relational and Structural dimensions) had positive significant effect on organizational entrepreneurship

Immunohistochemical and bacteriological investigations of mannheimia haemolytica in sheep bronchopneumonia

Mannheimia haemolytica infection is one of the most common etiologic agents of sheep pneumonia almost all over the world. Ovine pneumonic Mannheimiosis is characterized by severe fibrinous pleuropneumonia. Subacute to chronic cases progress to purulent bronchopneumonia and its squeals include abscessation and fibrous pleural adhesions. In the present study, lungs of 8986 sheep were inspected grossly in the Ahvaz abattoir and totally 65 lungs with visible signs of bronchopneumonia were selected for pathological and bacteriological examinations. Mannheimia haemolytica antigens were detected in 63.07% of immunoperoxidase stained tissue sections while 52.30% of the lungs were positive in bacteriological culture. Suppurative, necrotic and fibrinous types of bronchopneumonia were the most abundant lesions and right cranial lobes, specifically their cranial portions, were the most affected areas. McNemar test showed a significant difference between the diagnostic power of immunohistochemistry (IHC) and bacterial culture in detection of M. haemolytica (κ=0.66). Considering IHC as a golden test, sensitivity and specificity of bacterial culture were estimated as 78.05 and 91.67%, respectively. Chi- squared test showed significant correlations between the distribution of the lesions and bacterial isolation (P=0.04), types of lesions and IHC results (P=0.01), and also types of bronchopneumonia and mixed/pure isolation (P=0.008). This study showed the significant role of Mannheimia haemolytica in causing pneumonic lesions of studied sheep

Replacement of salamon with shotor diluent and egg yolk with low density lipoprotein for chilled storage of ram semen

Summary The present study investigated the possibility of replacing salamon with modified shotor diluent (MSD) and egg yolk (EY) with low density lipoprotein (LDL) for chilled storage of ram semen. Good quality semen (>80% progressive forward motility (PFM) of sperm) from 3 fertile rams was collected using an artificial vagina and pooled for each experiment. Low density lipoprotein was extracted from fresh EY. In experiment 1, semen was divided into 2 fractions and extended in MSD or salamon. In experiment 2, semen was assigned into 5 fractions and extended in MSD supplemented with 12 and 15% EY or 3, 5 and 8% LDL. In experiment 3, semen was divided into 2 fractions and extended in MSD supplemented with 12% EY or 5% LDL. Viability of sperm was assessed at times 0 (immediately after semen dilution), 2 or 4 (at 4°C) and up to 72 h after semen dilution. Data was analyzed using General Linear Model (GLM) procedure, including repeated measures. In experiment 1, the viability of sperm was similar in two diluents (P>0.05). In experiment 2, PFM of sperm was similar among groups at the time of dilution (P>0.05); but remained elevated in 5 and 8% LDL compared to other groups afterward (P<0.05). In experiment 3, PFM of sperm was superior at 48 and 72 h after dilution in 5% LDL compared to 12% EY (P<0.05). In conclusion, MSD supplemented with 5% LDL is a suitable diluent for ram fresh semen preserved at 4°C for 72 h

Lattice Boltzmann Simulation of Solid Particles Motion in a Three Dimensional Flow using Smoothed Profile Method

Three-dimensional particulate flow has been simulated using Lattice Boltzmann Method (LBM). Solid-fluid interaction was modeled based on Smoothed Profile Method (SPM) (Jafari et. al, Lattice-Boltzmann method combined with smoothed-profile method for particulate suspensions, Phys. Rev. E, 2011). In this paper a GPU code based on three-dimensional lattice Boltzmann method and smoothed profile method has been prepared due to the ability of SPM-LBM to perform locally and in parallel mode. Results obtained for sedimentation of one and two spherical particles as well as their behavior in shear flow showed excellent correspondence with previous published works. Computations for a large number of particles sedimentation showed that combination of LBM and SPM on a GPU platform can be considered as an efficient and promising computational frame work in particulate flow simulations