On the use of dated sediments to investigate historical nuclear discharges.

Studsvik, a Swedish nuclear research facility, has been releasing aquatic radioactive discharges in the Baltic Sea, through the bay Tvären, since 1959. The permissible discharge levels are regulated by the Swedish Radiation Safety Authority (SSM) but only information about 60Co, 137Cs, 152Eu, total alpha and beta activities were reported up to 2002. Since then, the reports cover most a more comprehensive set of radionuclides. In this context, the seabed can be utilized as a chronological archive to investigate historical Studsvik releases. To this end, 23 sediment cores covering the whole area of the bay were studied and 5 of them were dated using 210Pb-dating methods. Since the discharges from Studsvik contain both plutonium and caesium, neither can be used to validate the 210Pb-dating method. Instead, stable lead with maximum deposition, known to be dated to 1970, was used. Cobalt-60, 137Cs, and 152Eu depth distributions were studied from the dated sediment cores and compared with reported levels of aquatic discharges. The expected sediment 137Cs-peak from the fallout from the Chornobyl accident was however smeared out, indicating an ongoing inflow of 137Cs with the Baltic seawater. Our findings show that reported releases of aquatic discharges of 60Co and 152Eu are consistent with measured sediment activity distribution. The sediments from the deepest parts of Tvären, with intact chronology and with a high time resolution, are ideal for investigating historical nuclear discharges and can be a tool to investigate unreported radionuclide releases. Dated sediment can in this way be a tool for nuclear safeguards to evaluate past and present activities in nuclear facilities.

Gross and delta efficiencies during uphill running and cycling among elite triathletes.

PURPOSE: To investigate the gross efficiency (GE) and delta efficiency (DE) during cycling and running in elite triathletes. METHODS: Five male and five female elite triathletes completed two incremental treadmill tests with an inclination of 2.5° to determine their GE and DE during cycling and running. The speed increments between the 5-min stages were 2.4 and 0.6 km h-1 during the cycling and running tests, respectively. For each test, GE was calculated as the ratio between the mechanical work rate (MWR) and the metabolic rate (MR) at an intensity corresponding to a net increase in blood-lactate concentration of 1 mmol l-1. DE was calculated by dividing the delta increase in MWR by the delta increase in MR for each test. Pearson correlations and paired-sample t tests were used to investigate the relationships and differences, respectively. RESULTS: There was a correlation between GEcycle and GErun (r = 0.66; P = 0.038; R2 = 0.44), but the correlation between DEcycle and DErun was not statistically significant (r = - 0.045; P = 0.90; R2 = 0.0020). There were differences between GEcycle and GErun (t = 80.8; P < 0.001) as well as between DEcycle and DErun (t = 27.8; P < 0.001). CONCLUSIONS: Elite triathletes with high GE during running also have high GE during cycling, when exercising at a treadmill inclination of 2.5°. For a moderate uphill incline, elite triathletes are more energy efficient during cycling than during running, independent of work rate.

Nurses' Roles and Experiences with Enhancing Adherence to Tuberculosis Treatment among Patients in Burundi: A Qualitative Study.

Background. In TB control, poor treatment adherence is a major cause of relapse and drug resistance. Nurses have a critical role in supporting patients in TB treatment process. Yet, very little research has been done to inform policymakers and practitioners on nurses' experiences of treatment adherence among patients with TB. Aim. To describe nurses' experiences of supporting treatment adherence among patients with tuberculosis in Burundi. Method. The study adopted qualitative approach with a descriptive design. A purposive sampling was performed. Eight nurses were selected from two TB treatment centers in Burundi. Content analysis was used to analyze the data. Result. According to the nurses, most patients complete their treatment. Educating patients, providing the medication, observing and following up treatment, and communicating with the patients were the key tasks by nurses to support adherence. Causes for interruption were medication-related difficulties, poverty, and patients' indiscipline. Treatment adherence could also be affected by patients' and nurses' feelings. Providing transportation and meals could enhance treatment compliance. Conclusion. Nurses are critical resources to TB treatment success. In a poverty stricken setting, nurses' work could be facilitated and adherence further could be enhanced if socioeconomic problems (transportation and nutritional support) were alleviated.