Work-related Stress and Burnout Factors of Principals in Regional Greece: A Historical Perspective

Work-related stress and burnout is a reality in modern society, because the lack of time and the high work demands seem increasingly intensified. Thus, the study of working conditions and the factors that affect the physical and mental health becomes even more imperative. Professions that are particularly stressful are those where there is daily contact with people, for example, doctors, nurses, social workers, or school leaders. Besides administrative and official duties, modern principals perform additional functions such as the organization and management of schools, the coordination of people who are involved in the teaching and operational process and they intervene to reform and upgrade the work of their schools. In addition, they must have skills like cooperation ability, be knowledgeable in the psychology of individuals and groups, have perceptual and observation ability, administrative imagination and energy, have managerial experience and solid scientific training. Since burnout is the result of chronic work-related stress, the purpose of this study is to record the specific factors that create professional stress to school leaders and their correlation with burnout and other features, like gender or experience. This study has been conducted in a number of primary-education schools of a central region in Greece, where generally there are no monitoring practices followed, concerning the work stress of educators and their relevant support. Thus, it is perceived as a prerequisite for the designing of any supportive services and activities, if necessary

HyperReenact: One-Shot Reenactment via Jointly Learning to Refine and Retarget Faces

In this paper, we present our method for neural face reenactment, called HyperReenact, that aims to generate realistic talking head images of a source identity, driven by a target facial pose. Existing state-of-the-art face reenactment methods train controllable generative models that learn to synthesize realistic facial images, yet producing reenacted faces that are prone to significant visual artifacts, especially under the challenging condition of extreme head pose changes, or requiring expensive few-shot fine-tuning to better preserve the source identity characteristics. We propose to address these limitations by leveraging the photorealistic generation ability and the disentangled properties of a pretrained StyleGAN2 generator, by first inverting the real images into its latent space and then using a hypernetwork to perform: (i) refinement of the source identity characteristics and (ii) facial pose re-targeting, eliminating this way the dependence on external editing methods that typically produce artifacts. Our method operates under the one-shot setting (i.e., using a single source frame) and allows for cross-subject reenactment, without requiring any subject-specific fine-tuning. We compare our method both quantitatively and qualitatively against several state-of-the-art techniques on the standard benchmarks of VoxCeleb1 and VoxCeleb2, demonstrating the superiority of our approach in producing artifact-free images, exhibiting remarkable robustness even under extreme head pose changes. We make the code and the pretrained models publicly available at: https://github.com/StelaBou/HyperReenact .Comment: Accepted for publication in ICCV 2023. Project page: https://stelabou.github.io/hyperreenact.github.io/ Code: https://github.com/StelaBou/HyperReenac

HyperReenact: One-Shot Reenactment via Jointly Learning to Refine and Retarget Faces

In this paper, we present our method for neural face reenactment, called HyperReenact, that aims to generate realistic talking head images of a source identity, driven by a target facial pose. Existing state-of-the-art face reenactment methods train controllable generative models that learn to synthesize realistic facial images, yet producing reenacted faces that are prone to significant visual artifacts, especially under the challenging condition of extreme head pose changes, or requiring expensive few-shot fine-tuning to better preserve the source identity characteristics. We propose to address these limitations by leveraging the photorealistic generation ability and the disentangled properties of a pretrained StyleGAN2 generator, by first inverting the real images into its latent space and then using a hypernetwork to perform:(i) refinement of the source identity characteristics and (ii) facial pose re-targeting, eliminating this way the dependence on external editing methods that typically produce artifacts. Our method operates under the one-shot setting (ie, using a single source frame) and allows for cross-subject reenactment, without requiring any subject-specific fine-tuning. We compare our method both quantitatively and qualitatively against several state-of-the-art techniques on the standard benchmarks of VoxCeleb1 and VoxCeleb2, demonstrating the superiority of our approach in producing artifact-free images, exhibiting remarkable robustness even under extreme head pose changes

Underwater geophysical prospection in ancient Olous, Crete

We employ electrical resistivity tomography and magnetic gradiometry methods to the ultra-shallow submerged and littoral archaeological site of Olous. This allows reconstruction of the built environment that nowadays lie below the sea bottom, thus completing the respective archaeological evidence

Correlation of pre-existing radial artery macrocalcifications with late patency of primary radiocephalic fistulas in diabetic hemodialysis patients

ObjectiveThe aim of this study was to evaluate the impact of pre-existing radial artery macrocalcification (Mönckeberg type of arteriosclerosis) on patency rates of radiocephalic fistulas (RCFs) in diabetic end-stage renal disease (ESRD) patients undergoing hemodialysis.MethodsIn this observational prospective study, the long-term patency rates (primary outcome measures) of RCFs in ESRD diabetics who had Mönckeberg radial (±brachial) artery disease (calcified [C] group) were compared with those obtained in ESRD diabetics who had healthy, noncalcified vessels before RCF construction (healthy [H] group). Vessel calcification was assessed by plain two-dimensional radiography. For inclusion in the C-group, uniform linear railroad track-type macrocalcifications of at least 6 cm in length, in the medial wall of the radial artery ipsilateral to RCF creation, were required. Patients were included in the H-group if the radial artery ipsilateral to the RCF creation was free of any macrocalcification, of either intima or media type. Any intimal-like plaque with irregular and patchy distribution was an exclusion criterion for both groups. Patients in both groups also were required to have suitable upper limb vascular anatomy on the basis of ultrasound imaging before RCF creation (cephalic vein of minimum diameter of 1.6 mm, without stenosis or thrombosis in all outflow areas, and radial artery of minimum diameter of 1.5 mm, without proximal hemodynamically significant stenosis). Secondary outcome measures included all-cause mortality. Kaplan-Meier statistics were used for comparison between groups.ResultsThe arm radiograph at the site of possible fistula construction showed abnormality in 39 patients (C-group, 47 RCFs), whereas 33 patients had noncalcified (“healthy”) vascular anatomy (H-group, 40 RCFs). Mean duration of the diabetic disease at the time of RCF creation was 8.9 ± 5.6 years (range, 2-25 years) for the H-group and 14 ± 9.9 years (range, 1-40 years) for the C-group (P = .018). The mean follow-up period for H-group and C-group was 51.9 ± 35.9 months (range, 0.1-126 months) and 26.1 ± 31.6 months (range, 0.1-144 months), respectively (P = .0006). Forty-four patients died during the follow-up period. Primary patency rates at 12, 24, 36, and 48 months for C-group vs H-group were 50.2% vs 80%, 36.5% vs 72.3%, 32.4% vs 67.9%, and 29.1% vs 59.3% (P = .0019). Respective values for secondary patency rates were 52.4% vs 87.5%, 40.9% vs 82.4%, 36.6% vs 78.1%, and 33.2% vs 72.8% (P = .00064). Patient survival rates at 24 and 48 months were 56.1% and 46.4% for C-group and 92.4% and 67.4% for H-group, respectively (P = .05).ConclusionsESRD diabetics with radial artery Mönckeberg calcifications receiving RCFs had worse late clinical outcomes compared with ESRD diabetics with healthy distal arm vessels receiving the same access. The long-term benefit of RCFs may be lost in diabetics with extensively calcified vessels, and preferably the brachial artery should be used instead

Finding Semantically Related Videos in Closed Collections

Modern newsroom tools offer advanced functionality for automatic and semi-automatic content collection from the web and social media sources to accompany news stories. However, the content collected in this way often tends to be unstructured and may include irrelevant items. An important step in the verification process is to organize this content, both with respect to what it shows, and with respect to its origin. This chapter presents our efforts in this direction, which resulted in two components. One aims to detect semantic concepts in video shots, to help annotation and organization of content collections. We implement a system based on deep learning, featuring a number of advances and adaptations of existing algorithms to increase performance for the task. The other component aims to detect logos in videos in order to identify their provenance. We present our progress from a keypoint-based detection system to a system based on deep learning

Perceptions of Cooperating Teachers and University Supervisors of the Cooperating Teachers' Supervisory Role Regarding Planning and Instruction

151 p.Thesis (Ed.D.)--University of Illinois at Urbana-Champaign, 1992.The purpose of the study was to investigate and compare cooperating teachers' and university supervisors' perceptions of 32 supervisory activities performed by the cooperating teachers regarding their student teachers' planning and instruction. A survey instrument, consisting of 32 items describing commonly reported supervisory activities, was administered to 65 cooperating teachers and 12 university supervisors involved in secondary student teaching at the University of Illinois at Urbana-Champaign in the Spring Semester 1991.Inferential and descriptive statistics were used to report and analyze the perceptual responses of the two participating groups. Item means of the Likert measures were used to rank the items. Visual analysis produced three levels of use and helpfulness of the activities to student teachers as perceived by the cooperating teachers and the university supervisors. The \chi\sp2 statistic was used to identify three levels of agreement (high, medium, low) between the two groups.The findings indicated that the two groups expressed significant differences over the helpfulness of stated expectations for student teachers, the modeling of teaching methods and styles, and a concern for instructional organization. The cooperating teachers perceived that these activities were more helpful to student teachers than the university supervisors perceived them to be. The two groups were similar in their perceptions of the lack of helpfulness of formal conferences and the helpfulness of the activities that granted student teachers autonomy to plan their lessons. They agree that informal supervision of student teachers in which a sense of autonomy to plan on their own is passed to the student teachers is more helpful than formal supervision entailing technical systems of observation and evaluation.The similarities and differences of cooperating teachers' and university supervisors' perceptions of the helpfulness of the activities suggest the usefulness of in-service programs, to allow the two groups to share their educational philosophies and supervisory knowledge.It is recommended that further studies utilizing representative samples of elementary and secondary cooperating teachers, university supervisors, and student teachers, including direct observation of supervisory acts, would provide useful empirical information to the education literature.Additional studies should examine the other areas of cooperating teachers' responsibilities: orientation, evaluation, and professional development.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Pulse wave analysis and study of other hemodynamic parameters of the cardiovascular system in patients with infrarenal aortic occlusion

Patients undergoing revascularization for infrarenal aortic occlusion (IAO) have been reported to present improved survival rates compared to those treated conservatively. Aim of this study was to investigate the hemodynamic changes induced after revascularization for IAO, as expressed with pulse wave velocity (PWV), Augmentation Index (AIx), Augmentation Pressure (AP) and pulse wave reflection coefficient (RC). Twelve patients underwent revascularization (9 aortobifemoral / aortobiiliac bypasses, 2 primary iliac stenting and 1 hybrid procedure of unilateral aortoiliac stenting and crossover bypass). Calculation of hemodynamic parameters was performed in all patients preoperatively, at 1-month and 1-year postoperatively. Pulse wave analysis was performed noninvasively with a novel validated brachial cuff-based automatic oscillometric device (Mobil-O-Graph; IEM, Stolberg, Germany). The estimated hemodynamic parameters were augmentation index (AIx), augmentation pressure (AP), reflection coefficient (RC) and pulse wave velocity (PWV). Data were analyzed by the Friedman ANOVA test. Aix decreased significantly at 1-month and further at 1-year postoperatively compared to preoperative values (24±11 and 17±13 vs. 34±13.5 respectively, p<0.0006). AP decreased at 1-month and 1-year postoperatively compared to preoperative values (6.5±4mmHg and 8±6.5mmHg vs. 13±12mmHg respectively, p<0.045). RC decreased also at 1-month and 1-year postoperatively compared to preoperative values (62±5.5, 64±4.3 vs. 73±5.1 respectively, p<0.002). However, changes in PWV were less prominent in this short/term postoperative period. Improved hemodynamic profile may theoretically contribute to the enhanced survival rates of these patients.Σε ασθενείς οι οποίοι υποβάλλονται σε χειρουργική επέμβαση επαναιμάτωσης λόγω υπονεφρικής απόφραξης κοιλιακής αορτής (ΥΑΟ) παρατηρούνται βελτιωμένα ποσοστά επιβίωσης συγκριτικά με τους ασθενείς που λαμβάνουν συντηρητική αγωγή. Ο σκοπός της παρούσας διατριβής είναι να τεκμηριώσει τις αιμοδυναμικές αλλαγές που επέρχονται μετά την επαναιμάτωση της ΙΑΟ χρησιμοποιώντας δείκτες όπως η ταχύτητα μετάδοσης του σφυγμικού κύματος (PWV), ο δείκτης ενίσχυσης (AIx), η πίεση ενίσχυσης (AP) και ο δείκτης ανάκλασης (RC). Δώδεκα ασθενείς υπεβλήθησαν σε επέμβαση επαναιμάτωσης (9 ασθενείς σε οαρτο-διμηριαία/αορτο-διλαγόνια παράκαμψη, 2 ασθενείς σε πρωτογενές stenting και ένας ασθενή σε υβριδική επαναιμάτωση με διενέργεια αορτο-μονο-λαγόνιου stenting και ετερόπλευρη μηρο-μηριαία παράκαμψη). Η μέτρηση των αιμοδυναμικών παραμέτρων διενεργήθηκε σε όλους τους ασθενείς προεγχειρητικά, στον 1ο και 12ο μήνα. Πραγματοποιήθηκε μέτρηση της ανάλυσης της ταχύτητας του σφυγμικού κύματος (PWA) μέσω τονομετρίας με την τοποθέτηση περιχειρίδας στον βραχίονα βασιζόμενη στην συσκευή Mobil-O-Graph (IEM, Stolberg, Germany). Η συσκευή τονομετρίας πραγματοποιούσε ανάλυση των αιμοδυναμικών δεικτών όπως του δείκτης ενίσχυσης (Aix), της πίεσης ενίσχυσης (AP), του συντελεστή ανάκλασης (RC) και της ταχύτητας μετάδοσης του σφυγμικού κύματος (PWV). Η επεξεργασία των δεδομένων έγινε με την ανάλυση Friedman ANOVA. Ο Aix μειώθηκε σημαντικά στον 1ο και 12ο μήνα μετεγχειρητικά συγκριτικά με τις προεγχειρητικές μετρήσεις (24±11 και 17±13 έναντι 34±13.5 αντιστοίχως, p<0.0006). Η AP μειώθηκε στον 1ο και 12ο μήνα μετεγχειρητικά συγκριτικά με τις προεγχειρητικές τιμές (6.5±4 mmHg και 8±6.5mmHg έναντι 13±12mmHg αντιστοίχως, p<0.045). O RC μειώθηκε στον 1ο και 12ο μήνα μετεγχειρητικά συγκριτικά με την προεγχειρητική μέτρηση ( 62±5.5mmHg, 64±4.3mmHg έναντι 73±5.1 αντιστοίχως, p<0.002). Παρά ταύτα όσον αναφορά την PWV, δεν υπήρξαν στατιστικά σημαντικές μεταβολές στην άμεση και μεσοπρόθεσμη μετεγχειρητική περίοδος. Συνεπώς, το βελτιωμένο αιμοδυναμικό προφίλ των ασθενών με απόφραξη της υπονεφρικής αορτής θα μπορούσε θεωρητικά να συμβάλλει στην βελτίωση των αιμοδυναμικών παραμέτρων ως δείκτες αορτικής σκληρίας