Effect of Micro Silica on Alkali Activated Repair Mortar

Master's thesis in Structural EngineeringIn this era, concrete acts as a primary role in construction technology. Therefore, it is essential to pay widespread attention to the side effects of concrete products for the environment. On the other hand, the vulnerability of concrete against invasive environmental factors such as acids, sulfates, seawater, and freeze/thaw cycle can affect the concrete lifetime. Hence, it is smart to make significant investments to represent innovative methods to repair and extend the existing concrete structures against destructive factors mentioned above and utilize new material instead of cement to cover the weak points. Alkali activated material could be considered as a brilliant alternative to avoid the use of ordinary types of cement. This material can also be utilized in the shape of mortar to repair and improve the functionality of existing concrete structures. This thesis focused on using a wastage of metal production process as the base material to provide a binder with widespread potentials for using in repair mortars. Alkali-activated slag is going to substitute the ordinary portland cement to produce alkali-activated repair mortar. It is also tried to optimize the physical properties as well as compression and bond strength of this mortar for using in practice by finding the optimum percentage of micro silica powder. For this purpose, we do the vicat and mini-slump tests immediately after casting the mortar to measure the setting time and workability. Moreover, The slant shear test is done as well as the cubic compression test for different percentages of micro silica from 0 to 20. The slant shear test helps us to compare the bond strength of mortar in the desired bond interface. Besides, all experiments above will be compared with a reference mix design with ordinary Portland cement to make a better comparison with alkali-activated binders. As a result, 15% of micro silica shows an acceptable compressive and bond strength with allowable workability. Moreover, slag-based mortar shows a significantly shorter setting time compared to OPC mortar, which makes the alkali-activated mortar a considerable substitution for OPC mortars in repairing structures

Interpreting chain of events for safety analysis

Because of difficulties of safety analysis in large systems and the complexities of managing large amount of data in these systems, the need for a supporting system has become an important area of research. Managing requirements, components and failure modes of a large system for safety analysis without tool support is difficult and could result in skipping or missing details which may cause an accident.The main goal of this project is to develop a system model for safety analysis facilitation. Sequences of events in a system and its environment may cause an accident in the system?s environment. People often have problem following long cause-consequence sequences of events, while accidents with a short path from initiating event to accident are easy to identify. The system model developed in this project enables automatic generation of event sequences that can cause an accident to the environment of a system. For this purpose, the system model uses the domain ontology as its knowledge base. This ontology must contain cause-consequences reported from a safety expert. A rule engine is used for reasoning about these cause-consequence concepts and generating event chains. The process of developing this system model, how the system model uses a domain ontology as its knowledge base and how the cause-consequence concepts should be added to the domain ontology are described in this project. Finally, the developed system model is tested with a real world example (a simplified steam boiler) and the expected event chains generated automatically

Interpreting chain of events for safety analysis

Because of difficulties of safety analysis in large systems and the complexities of managing large amount of data in these systems, the need for a supporting system has become an important area of research. Managing requirements, components and failure modes of a large system for safety analysis without tool support is difficult and could result in skipping or missing details which may cause an accident.The main goal of this project is to develop a system model for safety analysis facilitation. Sequences of events in a system and its environment may cause an accident in the system?s environment. People often have problem following long cause-consequence sequences of events, while accidents with a short path from initiating event to accident are easy to identify. The system model developed in this project enables automatic generation of event sequences that can cause an accident to the environment of a system. For this purpose, the system model uses the domain ontology as its knowledge base. This ontology must contain cause-consequences reported from a safety expert. A rule engine is used for reasoning about these cause-consequence concepts and generating event chains. The process of developing this system model, how the system model uses a domain ontology as its knowledge base and how the cause-consequence concepts should be added to the domain ontology are described in this project. Finally, the developed system model is tested with a real world example (a simplified steam boiler) and the expected event chains generated automatically

Yoga inom ämnet Idrott och hälsa : En kvalitativ studie om lärares syn på yoga iundervisningen inom idrott och hälsa

Purpose & question The purpose of the study is to investigate how the teachers in the subject of sports and healthlook at yoga, as well as whether yoga can be implemented in teaching within the subject ofsports and health in relation to students stress management/reduction. • What is the view of teachers in sports and health on yoga as content in the teaching? • How is yoga used in practice? • Teachers in the subject of sports and health see yoga as an effective method to reducethe student's stress level? Method The study has a qualitative approach and data was collected using five semi-structuredinterviews with physical education teachers at three different high schools in northern Stockholm. The study used a thematic analysis to identify different themes and important aspects from the interviews and the compilation of the results. The analysis was based on fourdifferent aspects such as salutogenic and pathogenic perspectives, Bourdieus concept of habitus and Engströms logics of practice. Results Three out of five participants had a positive attitude towards yoga as lesson content, the othertwo participants were neutral towards it. They saw no purpose in integrating something new into the teaching and making it rigid. Yoga today is used in different ways, ranging from thepurpose of experiencing mindfulness and relaxation to focusing solely on mobility. Three out of five participants were aware of the connection that yoga can work as a method for stressreduction. Conclusion The study shows that yoga is a method that can be used for stress reduction among highschool students, and that the use of yoga in teaching creates a good variety of content andgoes against the normative view of sports. The implementation of yoga in teaching alsoincreases the content of inclusive teaching and reduces the performance requirement withinthe subject and reduces the stress created by performance. Syfte & frågeställning Syftet med studien är att undersöka hur lärarna inom ämnet idrott och hälsa ser påyoga, samt om yoga kan implementeras i undervisningen inom ämnet idrott och hälsa irelation till elevernas stresshantering/reducering.• Vilken syn har lärare inom idrott och hälsa på yoga som innehåll i undervisningen?• Hur används yogan i praktiken?• Ser lärare inom ämnet idrott och hälsa på yoga som en effektiv metod att minskaelevens stressnivå? Metod Studien har en kvalitativ ansats och data samlades in med hjälp av fem semi-strukturerade intervjuer med idrottslärare på tre olika gymnasieskolor i norra Stockholm. Studien använde sig av en tematisk-analys för att identifiera olika teman och aspekter från intervjuerna och sammanställandet av resultatet. Analysen grundandes i fyra olika aspekter som salutogent- och patogent perspektiv, Bourdieus begrepp habitus samt Engströms praktiker/logiker. Resultat Tre av fem deltagare hade en positiv inställning gällande yoga som lektionsinnehåll, de övriga två deltagarna var neutrala mot det. De såg inget syfte att integrera något nytt i undervisningen och göra det krystat. Yoga idag används på olika sätt, antigen i syftet att uppleva mindfullness och avkoppling till att enbart fokusera på rörlighet. Tre av fem deltagare anser att yoga kan fungera som metod för stressreducering. Slutsats Studien visar att yoga är en metod som kan användas för stressreducering bland gymnasieelever, samt att användningen av yoga i undervisningen skapar en god variation av innehållet och går emot den normativa synen på idrott. Implementeringen av yoga i undervisningen ökar även innehållet med inkluderande undervisning och minskar prestationskravet inom ämnet och reducerar stressen skapat av prestation

Yoga inom ämnet Idrott och hälsa : En kvalitativ studie om lärares syn på yoga iundervisningen inom idrott och hälsa

Purpose & question The purpose of the study is to investigate how the teachers in the subject of sports and healthlook at yoga, as well as whether yoga can be implemented in teaching within the subject ofsports and health in relation to students stress management/reduction. • What is the view of teachers in sports and health on yoga as content in the teaching? • How is yoga used in practice? • Teachers in the subject of sports and health see yoga as an effective method to reducethe student's stress level? Method The study has a qualitative approach and data was collected using five semi-structuredinterviews with physical education teachers at three different high schools in northern Stockholm. The study used a thematic analysis to identify different themes and important aspects from the interviews and the compilation of the results. The analysis was based on fourdifferent aspects such as salutogenic and pathogenic perspectives, Bourdieus concept of habitus and Engströms logics of practice. Results Three out of five participants had a positive attitude towards yoga as lesson content, the othertwo participants were neutral towards it. They saw no purpose in integrating something new into the teaching and making it rigid. Yoga today is used in different ways, ranging from thepurpose of experiencing mindfulness and relaxation to focusing solely on mobility. Three out of five participants were aware of the connection that yoga can work as a method for stressreduction. Conclusion The study shows that yoga is a method that can be used for stress reduction among highschool students, and that the use of yoga in teaching creates a good variety of content andgoes against the normative view of sports. The implementation of yoga in teaching alsoincreases the content of inclusive teaching and reduces the performance requirement withinthe subject and reduces the stress created by performance. Syfte & frågeställning Syftet med studien är att undersöka hur lärarna inom ämnet idrott och hälsa ser påyoga, samt om yoga kan implementeras i undervisningen inom ämnet idrott och hälsa irelation till elevernas stresshantering/reducering.• Vilken syn har lärare inom idrott och hälsa på yoga som innehåll i undervisningen?• Hur används yogan i praktiken?• Ser lärare inom ämnet idrott och hälsa på yoga som en effektiv metod att minskaelevens stressnivå? Metod Studien har en kvalitativ ansats och data samlades in med hjälp av fem semi-strukturerade intervjuer med idrottslärare på tre olika gymnasieskolor i norra Stockholm. Studien använde sig av en tematisk-analys för att identifiera olika teman och aspekter från intervjuerna och sammanställandet av resultatet. Analysen grundandes i fyra olika aspekter som salutogent- och patogent perspektiv, Bourdieus begrepp habitus samt Engströms praktiker/logiker. Resultat Tre av fem deltagare hade en positiv inställning gällande yoga som lektionsinnehåll, de övriga två deltagarna var neutrala mot det. De såg inget syfte att integrera något nytt i undervisningen och göra det krystat. Yoga idag används på olika sätt, antigen i syftet att uppleva mindfullness och avkoppling till att enbart fokusera på rörlighet. Tre av fem deltagare anser att yoga kan fungera som metod för stressreducering. Slutsats Studien visar att yoga är en metod som kan användas för stressreducering bland gymnasieelever, samt att användningen av yoga i undervisningen skapar en god variation av innehållet och går emot den normativa synen på idrott. Implementeringen av yoga i undervisningen ökar även innehållet med inkluderande undervisning och minskar prestationskravet inom ämnet och reducerar stressen skapat av prestation

Comparing diagnostic techniques of magnetic resonance angiography (MRA) and Doppler ultrasonography in determining severity of renal artery stenosis

BACKGROUND: Renal artery stenosis is one of the important causes of hypertension and endstage renal failure. Magnetic resonance angiography (MRA) and Doppler ultrasonography arenon-invasive and safe diagnostic techniques that have also high sensitivity and specificity. Sincethe accuracy and reliability of these techniques depend upon technicians and softwares, wedecided to evaluate and compare the sensitivity and specificity of these techniques in Isfahan.METHODS: Our study included all the patients (37 patients) who underwent renal arteryangiography during 2 years from May 2003 to May 2005 and up to six months after that hadunderwent MRA (21 patients) and Doppler sonography (16 patients) in Isfahan. Renal arteryangiography was considered as the gold standard.RESULTS: Sensitivity, specificity, positive and negative predictive values of 100%, 25%, 25%,and 100% were obtained for MRA respectively. Specificity and positive predictive values (PPV)of Doppler sonography were 67%. Its sensitivity and negative predictive values (NPV) were 57%.CONCLUSION: Although it seems that technician dependency, technical and softwareproblems were the reasons of low specificity of gadolinium-enhanced MRA in our study, furtherstudies with larger sample sizes are recommended.Keywords: MRA, Doppler Ultrasonography, Renal Artery Stenosis

MODIFIED PERCUTANEOUS TRANSLUMINANT SEPTAL MYOCARDIA ABLATION: A NEW METHOD FOR HYPERTROPHIC CARDIOMYOPATHY MANAGEMENT

Introduction. Familial hypertrophic cardiomyopathy (HCM) occurs as an autosomal dominant mendelian inherited disease in about 50 percent cases. abstractive and nonobstractive were two forms of HCM. The most common treatment modalities include drug therapy, mitral valve replacement, installation of dual chamber DD pacemaker and surgical excision of a portion of the hypertrophied septum. Methods. One of the newest methods used in recent years for the treatment of HCM unresponsive to common medical procedures is to inject alcohol into septal artery (septal ablation). We used a modified version of this procedure which consisted of using transesophageal echocardiography evaluation of mitral regurgitation and the diagnosis of septal artery during alcohol injection in a HCM patient. Results. The short term (immediately after procedure) and the long term (after 3 months) evaluation indicates complete improvement of clinical symptoms in the patient. Discussion. Considering the clinical improvement of symptoms, increased tolerance for activity and reduced gradient in LV outflow tract, this procedure is an effective method for the treatment of HCM resistant to common medical therapy

Evaluation of accuracy of Euroscore risk model in prediction of perioperative mortality after coronary bypass graft surgery in Isfahan*

Background: This study aimed to evaluate the accuracy of Euroscore (European System for Cardiac Operative Risk Evaluation) in predicting perioperative mortality after cardiac surgery in Iranian patient population. Methods: Data on 1362 patients undergoing coronary bypass graft surgery (CABG) from 2007 to 2009 were collected. Calibration was assessed by Hosmer-Lemeshow goodness-of-fit. Area under the curve (AUC) was used to assess score validity. Odds ratios were measured to evaluate the predictive value of each risk factor on mortality rate. Results: The overall perioperative in hospital mortality was 3.6% whereas the Euroscore predicted a mortality of 3.96%. Euroscore model fitted well in the validation databases. The mean AUC was 66%. Mean length of intensive care unit (ICU) stay was 2.5 ± 2.5 days. Among risk factors, only left ventricular dysfunction, age and neurologic dysfunction were found to be related to mortality rate. Conclusions: Euroscore did not have acceptable discriminatory ability in perioperative in hospital mortality in Iranian patients. It seems that development of a local mortality risk scores corresponding to our patients epidemiologic characteristics may improve prediction of outcome