https://www.um.edu.mt/library/oar/handle/123456789/99095 Mon, 13 Apr 2026 00:15:19 GMT 2026-04-13T00:15:19Z https://www.um.edu.mt/library/oar/handle/123456789/99119 Title: In our commitment to science [editorial] Abstract: Dear readers and authors of Xjenza Online, as Editor in-Chief, I am very pleased to announce the release of the first regular issue of 2022 of Xjenza Online. I am very glad that this year, with the valuable assistance and contribution of the two dedicated and skilful copy editors of Xjenza Online, Julia Curmi and Josse Schubert, the journal was able to start releasing Online First the articles accepted for publication in a timely manner, a tangible evidence of our commitment to the ongoing improvement of the services we provide. The issue opens with a study by Cutajar et al. on the moving patterns of five loggerhead sea turtles (Caretta caretta) rescued in Maltese waters and rehabilitated at the Aquaculture Directorate at Fort San Lu˙cjan. The GPS tracking revealed that the turtles frequented the same main region to the South of the Maltese islands, typically the Libyan and Tunisian neritic coastal zones covered similar mean distances (11.2–22.4 km/day), despite differences in their life-stages and physical abilities. [excerpt] Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/99119 2022-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/99111 Title: Tracking Caretta caretta : movement patterns following rehabilitation in Malta Authors: Cutajar, Martina; Ferlat, Celine; Attard, Vincent; Gruppetta, Anthony Abstract: GPS tracking through the use of satellite transmitters has proved to be a useful technology in identifying migratory patterns in juvenile and adult sea turtles, despite being a relatively new tool in behavioural biology. This technology has allowed tracking to take place over larger areas and for longer periods of time than previously possible. Loggerhead sea turtles (Caretta caretta) are able to travel over large distances throughout their life, being able to travel up to 13,000 km in one year, visiting distant areas and often demonstrating complex patterns of movement both as juveniles and adults. However, information on the tracking of loggerhead turtles rehabilitated and released from the Maltese islands is scarce. This study followed the paths taken by five loggerhead sea turtles, four of which were juveniles while one was a full male adult. All turtles were rescued in Maltese waters and rehabilitated at the Aquaculture Directorate at Fort San Luċjan. The turtles spent between 205 and 1550 days at the rehabilitation centre, depending on the severity of their injuries. Three of these turtles were missing either a front or a hind limb. Turtle movements were recorded as X-Y coordinates using Argos System Applications. This information was gathered using Collecte Localisation Satellite (CLS). Following release, all five turtles were observed to frequent the same main region to the South of the Maltese islands, typically the Libyan and Tunisian neritic coastal zones, with few discrepancies also being recorded. The maximum daily speed recorded ranged between 2.4 and 8.0 km/h. The total distance travelled by the turtles under study ranged between 1375 km and 3273 km in 92 and 292 days respectively. The five turtles covered similar mean distances (11.2 – 22.4 km/day), despite differences in their life-stages and physical abilities. These results suggest that despite their physical limitations, turtles having missing limbs moved at speeds and covered distances comparable to their fully able counterparts. Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/99111 2022-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/99110 Title: Self-reported stressors and experiences of Maltese dental academics during the COVID-19 pandemic Authors: Agius, Anne-Marie; Vento Zahra, Ethel; Gatt, Gabriella; Cortes, Arthur R. G.; Attard, Nikolai J. Abstract: AIM: to compare self-reported outcomes among dental faculty members during the COVID-19 pandemic.; MATERIALS AND METHODS: An anonymous questionnaire consisting of 13 closed and open-ended questions was sent to all faculty members (n=41) at the Faculty of Dental Surgery at the university of this study. Categorical (likert-scale) and qualitative questions on self-reported outcomes were identified and tallied. Non-parametric tests were used to correlate and compare variables among the different gender, departments and roles of the academics (i.e. full-time, part-time, visiting and demonstrators).; RESULTS: Thirty-two (32) out of fourty-one (41) academics completed the online questionnaire. A satisfactory adaptation to online lecturing was noted from the majority of the participants. On the other hand, full-time faculty members were significantly more anxious about contracting COVID-19, than part-time and visiting faculty members (p=0.020). Most participants were concerned about the lack of practical training opportunities for students. There were no significant differences between gender categories for any of the variables explored in this study (p>0.05).; CONCLUSION: Academics accepted online platforms for lecturing and examinations as viable alternatives to traditional methods for theoretical learning but they were highly concerned about the possibility of students losing their practical skills during the lockdown and that online tutoring cannot compensate for lost hands-on time in preparation for their upcoming practical examinations. They, however, recognized the benefits of blended modes of tuition in the future. Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/99110 2022-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/99107 Title: Identifying risk factors of aortic valve replacement using survival frailty models Authors: Camilleri, Liberato; Grech, Lawrence; Manche, Alexander Abstract: Traditional survival modeling techniques, including the Kaplan Meier estimator, Cox regression and parametric survival models assume a fairly homogeneous population, where variation in survival durations can be explained by a small number of observed explanatory variables. However, in the presence of heterogeneity, frailty models are more appropriate to model survival data by introducing random effects that account for the variability generated from unobserved covariates. This paper presents two types of frailty models. The unshared frailty model assumes that different individuals have distinct frailties, while the shared frailty model assumes that the population can be divided into clusters, where members in the same cluster share the same frailty. Due to their nice mathematical properties, the Gamma and the Inverse Gaussian distributions are the most popular choices for the frailty distribution. These survival models are fitted to a data set using the facilities of STATA. The participants are patients who underwent an aortic valve replacement procedure at a Maltese hospital between 2003 and 2019. The dependent variable is the duration till death or till censored and the eleven predictors provide information about the patients’ health condition; surgery operative procedures; and duration of convalesce period. Moreover, in shared frailty models the patients are clustered by their diabetic condition since it is known that diabetic patients are more at risk of dying following aortic surgery. Sat, 01 Jan 2022 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/99107 2022-01-01T00:00:00Z