50 research outputs found
Multicentre investigation of neutron contamination at cardiac implantable electronic device (CIED) location due to high-energy photon beams using passive detectors and Monte Carlo simulations
Radiotherapy treatments involving LINACs operating at accelerating potentials >10 MV generate (photo)neutrons which deliver dose to patients also outside the target volume. This effect is particularly relevant for patients with cardiac implantable electronic devices (CIEDs), which can be damaged by the therapeutic irradiation. In the last few years, there has been a rising interest in this issue, and it seems that damage to CIEDs is primarily associated with the thermal component of the photoneutron field. In particular, a recent study led by Politecnico di Milano considered CIEDs from various manufacturers and showed that some of these devices can be damaged after an irradiation with a thermal neutron fluence of about 10^9 cm^-2. The present work results from a collaboration among Politecnico di Milano, the University of Pisa, the University of Trieste and three Italian hospitals located in Lucca, Trieste and Varese, respectively, and it is primarily aimed at evaluating the thermal neutron fluence in CIED region for some high-energy treatments delivered at 15 and 18 MV and to determine whether it is comparable to the critical value given above, which has been experimentally determined to be potentially harmful for CIEDs. Thermal neutron fluence was measured through CR-39 detectors and TLDs, which were housed inside a BOMAB-like phantom mimicking the patient’s trunk. The experimental sessions involved two models of LINAC, Varian Clinac DHX (Varese hospital) and Elekta Synergy (Lucca and Trieste hospitals). The experimental results show that the treatments considered in this study can lead to a thermal neutron fluence in the cardiac region comparable to the critical value. Furthermore, detailed Monte Carlo geometries for the facilities involved in this project were developed with the MCNP code (v. 6.2), and they were tested by comparing simulation results to measurements considering some benchmark irradiation plans. Bubble detectors were also employed for fast neutron fluence measurements to be compared to simulation outputs. These computational models stand out as promising tools for the investigations required in this work, and they can be used for further studies also extending their use to analogous facilities hosting the same models of LINACs
World Meteorological Organization Assessment of the Purported World Record 58°C Temperature Extreme at El Azizia, Libya (13 September 1922)
On 13 September 1922, a temperature of 58°C (136.4°F) was purportedly recorded at El Azizia (approximately 40 km south-southwest of Tripoli) in what is now modern-day Libya. That temperature record of 58°C has been cited by numerous world-record sources as the highest recorded temperature for the planet. During 2010–11, a World Meteorological Organization (WMO) Commission of Climatology (CCl) special international panel of meteorological experts conducted an in-depth investigation of this record temperature for the WMO World Archive of Weather and Climate Extremes (http://wmo.asu.edu/). This committee identified five major concerns with the 1922 El Azizia temperature extreme record, specifically 1) potentially problematical instrumentation, 2) a probable new and inexperienced observer at the time of observation, 3) unrepresentative microclimate of the observation site, 4) poor correspondence of the extreme to other locations, and 5) poor comparison to subsequent temperature values recorded at the site. Based on these concerns, the WMO World Archive of Weather and Climate Extremes rejected this temperature extreme of 58°C as the highest temperature officially recorded on the planet. The WMO assessment is that the highest recorded surface temperature of 56.7°C (134°F) was measured on 10 July 1913 at Greenland Ranch (Death Valley), California
Assessing and promoting psychological wellbeing among healthcare employees
This thesis presents two studies conducted over several years in the field of psychological wellbeing within the National Health System in Malta. The thesis is entitled' Assessing and promoting psychological wellbeing among healthcare employees'. The first study in this project aimed at assessing the psychological wellbeing of all the healthcare employees working within the NHS in Malta while the second study aimed at promoting psychological wellbeing with a small group of physiotherapists working within an NHS Outpatients Clinic in Malta. A further aim of this thesis was to learn more about the possibility of emancipatory change through empowerment, drawing from a Participatory Action Research (PAR) design. Incorporating the two studies exemplified the values in Counselling Psychology, in taking a detailed assessment of the context and the lived experience of the people being studied and then helping in bringing about a change in the situation for the better through co-participation and empowerment of the research participants. The experience of conducting this research has 'enabled the researcher to further develop the value of pragmatism as a way of appreciating the use of both quantitative and qualitative research methodologies. Pragmatism also allowed the researcher to embrace methods that were appropriate and is thus resonant with the value system of the researcher to be driven by the aims of the research. Empowerment was a recurring theme within the two studies. Together, the two studies can be seen as a research endeavour with three aims: 1. To assess and explore the psychological wellbeing of the employees working within the Maltese National Health System. 2. To translate and examine the factor structure of the Maltese version of the GHQ-28. 3. An attempt to enhance the current situation in a way that could potentially lead to further positive changes in the future through the empowerment of the participants themselves and the insights they gain during this process. Study 1 assessed the wellbeing of employees from different occupational groups who filled in the General Health Questionnaire -28 (N=1 13 1). Furthermore, in this study five focus groups were conducted with two directors, five physiotherapists, five nurses, nine nursing officers and four health inspectors. The use of a mixed methods research design provided more depth to the analysis as the qualitative data complemented the quantitative data. This provided the basis for Study 2 in which a Participatory Action Research design was utilized with a small group of five physiotherapists. The outcome of this research benefited other employees within the organization, and can be further applied with other occupational groups. The relative lack of empirical research about the psychological wellbeing of health care employees in Malta to date highlights the significance of this thesis. The findings from this thesis will contribute to the understanding of the significance of utilizing PAR as an intervention designed to promote psychological wellbeing within organizations. Furthermore, the experience of the participants in working within this particular organization may be generalized to other related settings. This thesis can be an inspiration to those who aspire to empower others within the organization.EThOS - Electronic Theses Online ServiceGBUnited Kingdo