18 research outputs found

    Effect of Field of View and Resolution in Detection of Horizontal Root Fractures in CBCT images: An In Vitro Study

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    Introduction: New cone-beam computed tomography (CBCT) devices are capable of imaging with different resolutions and field of views (FOVs), in which higher resolutions and FOVs impose a higher dose to the patient. This study was an attempt to investigate the detection accuracy from different FOVs and resolutions in detection of horizontal root fractures.  Methods and Materials: Through this experimental study, in five different field of views (FOV) and resolutions (voxel size) of New Tom VGi CBCT (Italy) system was used to scan fifty teeth with horizontal root fractures in half of them. The images were evaluated by four observers (two maxillofacial radiologists and two general dentists) who recorded the presence or absence of horizontal root fractures. The data were analyzed by SPSS 22 software and MacNemar and kappa test were used to compare results with reality. Results: The highest sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy (AZ) were attributed to 8×8 FOV and high resolutions (0.125 mm voxel size) but the difference between sensitivity, specificity, PPV and NPV was not significant. Kappa values for inter-observer agreement between radiologists and general dentists and also intra-observer agreement were in excellent ranges. The highest Kappa in both cases was attributed to 8×8 FOV and high resolutions. Conclusion: There was no significant difference to diagnose of horizontal root fracture between two observer groups and for all of the FOVs and voxel sizes. Keywords: Cone-Beam Computed Tomography; Field of View; Horizontal Root Fracture

    An overview of biotechnological production of propionic acid: From upstream to downstream processes

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    The increasing demand for propionic acid (PA) production and its wide applications in several industries, especially the food industry (as a preservative and satiety inducer), have led to studies on the low-cost biosynthesis of this acid. This paper gives an overview of the biotechnological aspects of PA production and introduces Propionibacterium as the most popular organism for PA production. Moreover, all process variables influencing the production yield, different simple and complex carbon sources, the metabolic pathway of production, engineered mutants with increased productivity, and modified tolerance against high concentrations of acid have been described. Furthermore, possible methods of extraction and analysis of this organic acid, several applied bioreactors, and different culture systems and substrates are introduced. It can be concluded that maximum biomass and PA production may be achieved using metabolically engineered microorganisms and analyzing the most significant factors influencing yield. To date, the maximum reported yield for PA production is 0.973 g\ub7g-1, obtained from Propionibacterium acidipropionici in a three-electrode amperometric culture system in medium containing 0.4 mM cobalt sepulchrate. In addition, the best promising substrate for PA bioproduction may be achieved using glycerol as a carbon source in an extractive continuous fermentation. Simultaneous production of PA and vitamin B12 is suggested, and finally, the limitations of and strategies for competitive microbial production with respect to chemical process from an economical point of view are proposed and presented. Finally, some future trends for bioproduction of PA are suggested

    The Effect of 8 Weeks of Mult –Joint and Single–Joint Resistance Training on Some Coagulation and Blood Factors in Active Young Men

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    Introduction The alterations and imbalances in homeostasis are one of the main causes of heart attack. Th8ere is a discrepancy about the effects of various types of exercise, exercises, especially resistance exercises on coagulation factors. The objective of this study was to examine the effect of 8 weeks single joint and multiple joint resistance training on some coagulation and blood factors of active young men. Materials and Methods 30 subjects (20-26 years) were selected with randomly distributed in control group (n=10), single joint resistance training (n=10), and multi-joint resistance training (n=10). The experimental groups performed protocols for 8 weeks, three sessions each week. The Shapiro-Wilk test was used to determine the normality of the data and the differences were compared using the Ancova test and if significant results were reached, Bonferroni test was used. Results The single joint and multi-joint resistance training group had a significant effect on platelet (P<0.001). The type of protocol and resistance training did not have a significant effect on Platelet cell distribution Width (P=0.34). According to the findings, it can be said that both types of training had a significant effect on hematocrit and Erythrocyte Sedimentation (P=0.001), and in general, the effect of resistance training, regardless of its type, was effective on hematocrit and erythrocyte sedimentation (P=0.003, P<0.001). Conclusion The 8 weeks of resistance training reduces the number of platelets and also decreases hematocrit and reduces the blood sedimentation, which indicates a reduction in the risk of cardiovascular attacks while exercising

    An overview of biotechnological production of propionic acid: From upstream to downstream processes

    No full text
    The increasing demand for propionic acid (PA) production and its wide applications in several industries, especially the food industry (as a preservative and satiety inducer), have led to studies on the low-cost biosynthesis of this acid. This paper gives an overview of the biotechnological aspects of PA production and introduces Propionibacterium as the most popular organism for PA production. Moreover, all process variables influencing the production yield, different simple and complex carbon sources, the metabolic pathway of production, engineered mutants with increased productivity, and modified tolerance against high concentrations of acid have been described. Furthermore, possible methods of extraction and analysis of this organic acid, several applied bioreactors, and different culture systems and substrates are introduced. It can be concluded that maximum biomass and PA production may be achieved using metabolically engineered microorganisms and analyzing the most significant factors influencing yield. To date, the maximum reported yield for PA production is 0.973 g·g-1, obtained from Propionibacterium acidipropionici in a three-electrode amperometric culture system in medium containing 0.4 mM cobalt sepulchrate. In addition, the best promising substrate for PA bioproduction may be achieved using glycerol as a carbon source in an extractive continuous fermentation. Simultaneous production of PA and vitamin B12 is suggested, and finally, the limitations of and strategies for competitive microbial production with respect to chemical process from an economical point of view are proposed and presented. Finally, some future trends for bioproduction of PA are suggested

    Investigating the Effective Factors on Mobile Learning in Medical Education Based on FRAME Model

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    Introduction: With regard to an increase in use of modern communication technologies including mobile facilities and their application in learning and training, taking quality and users’ needs into account is a fundamental matter. In this article, an attempt has been made to investigate the factors influencing mobile learning from the perspective of M.S. and Ph.D. medical sciences students studying at Isfahan University of Medical Sciences based on FRAME model. Methods: In this descriptive study, the sample included 150 graduates M.Sc. and Ph.D. students of allied health medicine(Nursing , Midwifery and Hygiene fields ) in Esfahan University of Medical Sciences in 2013 that were selected through stratified random sampling. Data gathering tool was researcher-made questionnaire including 29 questions based on FRAME model. Face and content validity of the tool was confirmed and the reliability of internal consistency index (Cronbach’s Alpha) was 0.84 and finally we used descriptive statistics for data analysis. Results: The results showed that in learner component, the highest mean (3.85±1.08) related to learner's attitude towards mobile phone as a learning tool. In social component, the highest mean (3.24±1.04) belonged to the use of mobile phones for interaction with classmates. In interaction learning component, the highest mean (2.48±0.97) related to use of this device for transfer of ideas and information with other learners. In the usability of the device component, the highest mean (3.37±1.46) related to the use of cell phones for educational and research activities throughout the day. In social technology component, the highest mean (3.90±0.92) related to the use of electronic books in education. Finally in tool component, the results showed that learners prefer a flat touch screen mobile phone with high processing speed and having more than 3 GB memory in average size . Conclusion: With regard to the obtained results, designers of M-learning tools should take the users’ preferences into account and produce those tools, maximizing the efficacy of such learning type

    Extravascular lung water measurement in critically ill patients

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    In intensive care patients, due to increase in hydrostatic pressure and hyperpermeability state, pulmonary edema occurs. In this review, we discussed about definition and amount of extravascular lung water index (EVLWI) which relates to an increasing pulmonary capillary hydrostatic pressure or increasing capillary permeability. EVLWI-to-intrathoracic blood volume ratio is useful in determining the cause of pulmonary edema. EVLWI can be helpful in approximation of the amount of fluid overload and capillary leak in acute inflammatory injury. This is identified as a prognostic marker that is related to respiratory function and mortality in patients with acute respiratory distress syndrome and sepsis. Usage of EVLWI for determining of pulmonary edema in children would be beneficial

    Effect of UVC and UVA Photocatalytic Processes on Tetracycline Removal Using CuS-Coated Magnetic Activated Carbon Nanocomposite: A Comparative Study

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    In this study, we synthesized a novel MAC nanocomposite using almond’s green hull coated with CuS. The whole set of experiments have been conducted inside a batch (discontinuous reactor system) at room temperature. The effectiveness of different parameters in tetracycline removal pH (3, 5, 7, and 9), pollutant concentration (5–100 mg/L), nanocomposite dosage (0.025–1 g/L), and contact time (5–60 min) using newly synthesized nanocomposite were investigated. Based on the results, in the optimal conditions of pH = 9, nanocomposite dosage of 1 g/L, pollutant concentration of 20 mg/L, contact time of 60 min, and room temperature, 95% removal efficiency was obtained. In MAC/CuS/UVC process, the removal of COD and TOC were 76.89% and 566.84% respectively meanwhile, these values in MAC/CuS/UVA process were 74.19% and 62.11%, respectively. The results of nanocomposite stability and magnetic recovery illustrated that the removal efficiency was reduced by 1.5% in the presence of UVC and 5% in the presence of UVA lights during all six cycles. Therefore, this nanocomposite was highly capable of recycling and reuse. It can be concluded that considering the high potential of the synthesized nanocomposite, the photocatalytic efficiency of the MAC/CuS/UVC process in tetracycline synthesis was higher than MAC/CuS/UVA process
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