Chambre à étincelles optique pour la recherche de sources de rayons gamma

A gamma-ray telescope with a 850 cm2 multiplate spark chamber as a detector, has been used in an experiment of six balloon flights to investigate the Crab Nebula Pulsar 0532. The triggering signal is provided by a plastic scintillator-directional Čerenkov counter system. The spark chamber events are photographed by a stereo camera. The time of arrival of each event is recorded in UTC time with one millisecond accuracy, to search for a possible pulsed gamma emission from NP0532 above 50 MeV.</jats:p

Case-control study of factors associated with chronic Chagas heart disease in patients over 50 years of age

A case-control study on chronic Chagas heart disease (CCHD) was carried out between 1997 and 2005. Ninety patients over 50 years of age were examined for factors related to (CCHD). Fourty-six patients (51.1%) with Chagas heart disease (anomalous ECG) were assigned to the case group and 44 (48.9%) were included in the control group as carriers of undetermined forms of chronic disease. Social, demographic (age, gender, skin color, area of origin), epidemiological (permanence within an endemic zone, family history of Chagas heart disease or sudden death, physical strain, alcoholism, and smoking), and clinical (systemic hypertension) variables were analyzed. The data set was assessed through single-variable and multivariate analysis. The two factors independently associated with heart disease were age - presence of heart disease being three times higher in patients over 60 years of age (odds ratio, OR: 2.89; confidence interval of 95%: 1.09-7.61) - and family history of Chagas heart disease (OR: 2.833, CI 95%: 1.11-7.23). Systemic hypertension and gender did not prove to hold any association with heart disease, as neither did skin color, but this variable showed low statistical power due to reduced sample size