Previous research has found that users' interactions with others in online environments are often guided by the same rules and stereotypes we apply in our everyday lives. However, fewer studies have used virtual worlds as an experimental setting for the systematic examination of how avatar appearance and offline identity affect the outcome of users' actual interactions. This online field experiment measured the effect of avatar attractiveness, avatar gender, purported user gender, and favor size on the rate at which users received help across 2,300 separate user interactions. In addition, the main study's avatar gender, purported user gender, and favor size manipulations were replicated with a human avatar condition with 761 participants to examine whether trends for these factors' effects were similar with human avatars. In the main study, attractive avatars generally received more help than less attractive avatars. However, purported female users were helped less frequently than purported male users when represented by avatars that were either male or less attractive. Trends in the human avatar condition were similar to those observed in the main study. Implications for avatar-mediated communication and the persistence of sex roles in virtual environments are discussed. / Master of Arts

Θεωρητικό υπόβαθρο: Το οξειδωτικό στρες (ΟΣ) ορίζεται ως το παθολογικό αποτέλεσμα που προκύπτει από τη διαταραχή της ισορροπίας των κυτταρικών συγκεντρώσεων των οξειδωτικών, δραστικών ενώσεων και των αντιοξειδωτικών μορίων. Εκτός από τη βλάβη που υπόκεινται οι πρωτεΐνες και τα λιπίδια, το ΟΣ μπορεί επίσης να προκαλέσει μεταλλάξεις και επιγενετικές μεταβολές καταστρέφοντας τόσο το DNA όσο και τις πρωτεΐνες που τροποποιούν τη χρωματίνη. Παρ' όλα αυτά, στα θυρεοειδικά θυλακικά κύτταρα παράγονται σε καθημερινή βάση υψηλές ποσότητες υπεροξειδίου του υδρογόνου (H2O2), οξειδωτικής ουσίας απαραίτητης για την πραγματοποίηση της θυρεοειδικής ορμονογένεσης. Δεδομένου ότι ένα ελάχιστο ποσό οξειδωτικού φορτίου αποτελεί προϋπόθεση αφ’ενός για τη φυσιολογική λειτουργία των θυλακικών κυττάρων και αφ’ετέρου για την ανάπτυξη του θυρεοειδούς αδένα, πρόσφατα αποδείχτηκε ότι ο θυρεοειδής αδένας παρουσιάζει αυξημένη αμυντική ανταπόκριση έναντι του ΟΣ. Ωστόσο, οι ακριβείς μηχανισμοί με τους οποίους τα θυλακικά κύτταρα αντιλαμβάνονται και απαντούν στο ΟΣ παραμένουν ασαφείς. Ο NFE2-related factor 2 (Nrf2), ο οποίος κωδικοποιείται από το γονίδιο NFE2L2, είναι ένας μεταγραφικός παράγοντας ο οποίος απαντά σε σήματα κυτταρικού στρες και ανταποκρίνεται επιδρώντας στη μεταγραφή γονιδίων σε διάφορους τύπους ιστών. Σε βασικές συνθήκες, ο Nrf2 οδηγείται σε πρωτεασωματική αποικοδόμηση μέσω του κυτταροπλασματικού του αναστολέα, Keap1, ενώ σε συνθήκες ΟΣ, η αποικοδόμηση του Nrf2 δεν είναι δυνατή και ο Nrf2 εισέρχεται στον πυρήνα ώστε να ενεργοποιήσει τη μεταγραφή αντιοξειδωτικών γονιδίων όπως του γονιδίου Nqo1. Καθώς η οξειδοαναγωγική ομοιοστασία κατέχει κεντρικό ρόλο στην φυσιολογία του θυρεοειδούς αδένα και ο Nrf2 πρόσφατα χαρακτηρίσθηκε ως μεσολαβητής στην αντίσταση θυρεοειδικών καρκινικών κυτταρικών σειρών σε πρωτεασωμικούς αναστολείς, το αντιοξειδωτικό μονοπάτι Nrf2 μπορεί να θεωρηθεί ως εξαιρετικός υποψήφιος της διαμεσολάβησης της απόκρισης του θυρεοειδούς αδένα στο ΟΣ. Παρ 'όλα αυτά, ο ρόλος του μονοπατιού Nrf2 στον ανθρώπινο θυρεοειδικό καρκίνο παραμένει άγνωστος. Στόχος: Στόχοι της παρούσας μελέτης ήταν η εκτίμηση της δραστηριότητας του μονοπατιού Νrf2 στο διαφοροποιημένο καρκίνωμα του θυρεοειδούς αδένα και η διερεύνηση σωματικών μεταλλάξεων των γονιδίων NFE2L2 και Keap1. Yλικά και Μέθοδοι Ασθενείς: Στη μελέτη συμμετείχαν 90 περιστατικά εκ των οποίων τα 42 αφορούσαν θηλώδη καρκινώματα (papillary thyroid carcinomas, PTCs), τα 6 θυλακιώδη καρκινώματα (follicular thyroid carcinomas, FTCs) και τα υπόλοιπα 42 καλοήθεις όγκους (24 αδενώματα και 18 οζώδης υπερπλασία). Κυτταρικές σειρές: Στα πλαίσια της παρούσας μελέτης χρησιμοποιήθηκαν κυτταρικές σειρές PTC (K1, TPC-1, XTC-1), κυτταρική σειρά φτωχά διαφοροποιημένου PTC (T243), κυτταρικές σειρές αδιαφοροποίητου καρκινώματος (C643, 8505C, Hth74) και τέλος κυτταρικές σειρές αναπλαστικού καρκινώματος (T235 , T241, T238). Μέθοδοι: Αναδρομική ανοσοϊστοχημική ανάλυση δειγμάτων PTC και FTC, παρακείμενου φυσιολογικού ιστού και καλοηθών βλαβών. Ανάλυση αλληλουχίας DNA των κυτταρικών σειρών και PTC δειγμάτων. Κύριες μετρήσεις και υπολογισμοί: Αξιολογήθηκε η ένταση της ανοσοαντίδρασης των δειγμάτων των ιστών σε αντισώματα για τα Nrf2, Nqo1, Keap1 και 4-HNE. Μελετήθηκε η αλληλουχία του εξονίου 2 του γονιδίου NFE2L2 καθώς και του γονιδίου Keap1. Αποτελέσματα: O μεταγραφικός παράγοντας Nrf2 καθώς και ο στόχος του, η πρωτεΐνη Nqo1 ήταν μη ανιχνεύσιμα σε φυσιολογικό ιστό θυρεοειδούς αδένα. Τα επίπεδά τους ήταν σημαντικά υψηλότερα στα PTC δείγματα από ό,τι στα δείγματα καλοηθών βλαβών. Η έκφραση του Keap1 εμφάνισε διακύμανση στα δείγματα PTC με τα επίπεδά του να μην εμφανίζουν συσχέτιση με τα αντίστοιχα του Nrf2, ενάντια στη θεωρία πως τα μειωμένα επίπεδα του Κeap1 συνιστούν μηχανισμό ενεργοποίησης του Nrf2. Ο δείκτης ΟΣ, 4-HNE βρέθηκε αυξημένος στη πλειοψηφία των δειγμάτων PTC σε σχέση με το φυσιολογικό ιστό αναδεικνύοντας την ύπαρξη αυξημένου ΟΣ στο PTC. Επιπλέον, όσον αφορά τα δείγματα FTC, ο μεταγραφικός παράγοντας Nrf2 και η πρωτεΐνη Nqo1 ήταν ανιχνεύσιμα σε όλα τα δείγματα, ενώ τα επίπεδα του 4-ΗΝΕ ήταν αυξημένα. Όσον αφορά την ανάλυση αλληλουχίας DNA στις καρκινικές σειρές και σε 11 δείγματα PTC με υψηλή έκφραση Nrf2, καμία μετάλλαξη δεν ανευρέθηκε στο εξόνιο 2 του γονιδίου NFE2L2 και στο γονίδιο Keap1. Συμπεράσματα: Τα αποτελέσματα της μελέτης μας σε συνδυασμό με περαιτέρω μελέτες από το εργαστήριο Ενδοκρινολογίας και Ανατομικής του Πανεπιστημίου Πατρών καθώς και από το BC κέντρο έρευνας καρκίνου (Vancouver, Canada) αποδεικνύουν ότι το μονοπάτι Nrf2 ενεργοποιείται σε PTC και κατέχει ρυθμιστικό ρόλο στην αντιοξειδωτική απόκριση και τη βιωσιμότητα των θυρεοειδικών καρκινικών κυττάρων. Συνεπώς, αναδεικνύεται το Nrf2 μονοπάτι ως νέο “σήμα κατατεθέν” του PTC. Παρά το γεγονός ότι δεν ήταν δυνατή η πραγματοποίηση στατιστικών συσχετίσεων στη μελέτη του FTC λόγω του περιορισμένου αριθμού δειγμάτων, το μονοπάτι Nrf2 φαίνεται να ενεργοποιείται επίσης στο FTC. Η σταθερή ενεργοποίηση του Nrf2 στο PTC και ενδεχομένως στο FTC δίνει το έναυσμα για περαιτέρω διερεύνηση του μονοπατιού αυτού σε όλα τα είδη θυρεοειδικού καρκίνου καθώς και της πιθανής διαγνωστικής, προγνωστικής, και/ή θεραπευτικής χρησιμότητας του μονοπατιού στο διαφοροποιημένο καρκίνο του θυρεοειδούς αδένα. / Scientific background: Oxidative stress (ΟS) is experienced by cells when pro-oxidant and electrophilic reactive species overwhelm the cell’s antioxidant and detoxification proteins. In addition to causing protein and lipid damage, oxidative stress can cause mutations and epigenetic perturbation by damaging DNA and proteins that modify chromatin. Nevertheless, in thyrocytes a daily basis high amounts of the oxidant hydrogen hyperoxide (H2O2) was generated due to the fact that H2O2 is a reactive oxygen species required for thyroid hormonogenesis. A minimal oxidative load is a prerequisite for normal thyroid cell function and development and it was recently shown that the thyroid has increased capacity for defending itself against OS. However, precise mechanisms by which thyrocytes sense and respond to OS remain obscure. NFE2-related factor 2 (Nrf2), encoded by NFE2L2 gene, is a transcription factor that integrates cellular stress signals and responds by directing transcriptional program in various tissues. In basal conditions, Nrf2 is targeted for proteasomal degradation by its cytoplasmic inhibitor, Kelch-like ECH-associated protein 1 (Keap1), while in oxidative stress Nrf2 degradation is abolished and Nrf2 accumulates in the nucleus where it transactivates protective genes such as NAD(P)H dehydrogonase quinone 1 (Nqo1). As redox homeostasis plays a principal role in thyroid gland’s physiology, and Nrf2 has recently been characterised as mediator of thyroid cancer cell lines’ resistance to proteasome inhibitors, the Nrf2 antioxidant pathway seems to be an excellent candidate for mediating the antioxidant response of the thyroid gland. Nevertheless, the activity status of the Nrf2 pathway in human thyroid cancer remains unknown. Objective: The aims of this study were to assess the activity status of the Nrf2 pathway in differentiated thyroid carcinoma and investigate somatic mutations in NFE2L2 and Keap1 genes. Μethods and Materials Patients: The study included 90 individual samples; 42 papillarz thyroid carcinomas (PTCs), 6 follicular thyroid carcinomas (FTCs) and 42 benign lesions (24 adenomas and 18 nodular hyperplasias). Cell lines: Ten thyroid cell lines are used for this study: The PTC cell lines, K1, TPC-1 and XTC-1; the poorly differentiated PTC cell line, T243; the undifferentiated carcinoma cell lines, C643, 8505C and Hth74; and the anaplastic carcinoma cell lines, T235, T241 and T238. Methods: We conducted retrospective immunohistochemical analyses of PTC and FTC specimens, adjacent normal tissue, and benign lesions; DNA sequencing in cell lines and PTC samples. Main Outcome Measures: We assessed the abundance of Nrf2, Nqo1, Keap1, and 4HNE; and the sequence of NFE2L2 gene’s exon 2 and of KEAP1 gene. Results: Nrf2 and its target Nqo1 were undetectable in normal tissue; their levels were significantly higher in PTC than in benign lesions. The Nrf2 inhibitor, Keap1 was variably abundant in PTC, and its levels did not correlate with Nrf2, arguing against decreased levels as the mechanism for Nrf2 activation. The oxidized lipid 4HNE was more abundant in PTC than normal tissue indicating oxidative stress. In addition, as far as FTC samples are concerned, Nrf2 and Nqo1 were detectable in all samples as well as the levels of 4-HNE were significantly high. No mutations were detectable in exon 2 of NFE2L2 gene and in Keap1 gene. Conclusions: Our study’s results supported by further studies in laboratories of Endocrinology and Anatomy at University of Patras and BC Cancer Research Center (Vancouver, Canada) demonstrate that the Nrf2 pathway is commonly activated in PTC and that it regulates antioxidant responses and viability of cancer cells. Thus, Nrf2 is highlighted as a new hallmark of PTC. Although, statistic correlations were not possible in FTC samples’ study because of small sample size, the Nrf2 pathway seems to be also activated in FTC. The high activity of Nrf2 in PTC and possibly in FTC warrants further exploration of this pathway’s potential diagnostic, prognostic, and/or therapeutic utility in differentiated thyroid carcinoma.

The staphylococcal protein VgaA belongs to ARE ABCF family, which confers resistance to ribosome binding antibiotics by the target protection mechanism. VgaA confers resistance to lincosamides, streptogramins A and pleuromutilins and thus provides the so-called LSAP resistance phenotype. The expression of resistance genes often reduces fitness in the absence of an antibiotic, therefore the expression of resistance genes is often tightly controlled and triggered only in response to the presence of an antibiotic to which the protein confers resistance. The inducible expression has also been observed for the vgaA gene, nevertheless, its mechanism has not been elucidated. In the diploma thesis, it was shown that the vgaALC gene from Staphylococcus haemolyticus is regulated by ribosome-mediated attenuation. The mechanism is based on the detection of translation inhibitors via a ribosome translating a special regulatory open reading frame (uORF), which is part of an attenuator located in the 5' untranslated region of the mRNA. The vgaALC gene is regulated at the transcriptional level in response to LSAP antibiotics. Antibiotic specificity of induction is affected not only by the nature of the peptide encoded by uORF but also by the antibiotic specificity of the resistance protein. Fluorescence microscopy...

The Diploma thesis analyses the existential construction there is/are and its Czech translation equivalents. The existential construction is used to present a new phenomenon and is thus one of the basic forms of the presentation scale. Even though it is a commonly used construction in English, there is no direct equivalent in Czech. It was, therefore, assumed that the most common means of translating the existential sentences to Czech would be the verb být, the Czech equivalent of the verb be (as in There is a long way ahead of us. = Je před námi dlouhá cesta.), mít, the Czech equivalent of the verb have (as in There is a long way ahead of us = Máme před sebou dlouhou cestu) or other lexical verbs explicitly expressing existence of the given phenomenon, such as existovat (=exist), objevit se (=appear) and others. The theoretical part summarizes literature and previous work on the problematics of the presentation scale, presentation sentences and the construction there is/are. It also provides information about the functional sentence perspective, which is essential to the discussed topic. The final part of the theoretical section briefly discusses the previous work on the Czech translation equivalents of the existential construction. The aim of the empirical part was to gather 200 English...

The study elucidates the relation of Tom Stoppard's play Rosencrantz and Guildenstern Are Dead to Hamlet on the one hand and to the Theatre of the Absurd on the other. The two plays chosen to represent the Theatre of the Absurd are Samuel Beckett1 s Waiting for Godot and Harold Pinter* s The Caretaker. Since Stoppard is admired as a master craftsman of language, the emphasis is on his use of language. The extent to which the use of the cliché characterizes the three absurd plays is examined. It is found that the language area covered by the term cliche is not clearly defined and that the term is not uniformly applied. The inquiry centres on finding features, such as repetition, music-hall passages and "ready-made" language, that could explain why the dialogue in the three plays might appear cliche-ridden and on comparing the three plays in respect of these features. 　 The study further draws parallels between Stoppard's play and Waiting for Godot in the use of various techniques, such as misunderstandings, anticlimax and afterthought. It is found that there is often a conscious adoption by Stoppard of Beckett's techniques. To clarify the relation of Stoppard's play to Hamlet various aspects of the two plays are studied. These aspects include changes introduced into stereotyped expressions, punning, the use of parody and the handling of two specific motives, madness and death. Parallels are found in spite of the fact that several centuries separate the two plays, not least in respect to style, technique and language. / digitalisering@umu

A repeated theme in the fiction of Angela Carter and Jeanette Winterson is the use of domestic space as a tool for defining socially acceptable versions of female sexuality. Four novels that crystallize this theme are the focus of this dissertation: Winterson??s Oranges Are Not the Only Fruit (1985) and Art and Lies (1994) and Carter??s The Magic Toyshop (1967) and Nights at the Circus (1984). Each chapter examines both authors?? treatments of a specific room in the house. Chapter II, "Parlor Games: Spatial Literacy in Formal Rooms," discusses how rooms used for formal occasions project a desirable public image of a family. More insidiously, however, the rooms protect the sexual order of the household, which often privileges male sexuality. Using the term spatial literacy to describe how characters interpret rooms, the chapter argues that characters with a high spatial literacy can detect not only the overt messages of these formal rooms, but also what underlies those messages. Chapter III, "Making Meals, Breaking Deals: Mothers, Daughters, and Kitchens," discusses the kitchen as the site of the production of domestic comfort. An analysis of who has primary responsibility for the production of comfort and whose comfort is privileged often reveals the power hierarchy of a given household. The chapter also examines the kitchen as a volatile space that can erupt with violence and the expression of repressed emotions and repressed sexuality. Finally, the kitchen is analyzed as a space of intimacy between mothers and daughters. Chapter IV, "Bedtime Stories: Assaulting Sexuality in the Bedroom," argues that the privacy of the adolescent bedroom is often disrupted by the surveillance of family members trying to control the sexual identity of the room??s occupant. The chapter also examines how social prescriptions encourage women to tolerate the interruption of their privacy. Each of the protagonists from these four novels has opportunities to learn about subverting the discursive constructions of domestic space, and several characters enact that subversion. This ability for subversion suggests the possibility for agency, a possibility that postmodernist thought often rejects, but one that Carter and Winterson allow.

Summary Speaking about peculiarities of Cechovas creation in scientific literature, the two main features should be pointed out, i.e, laconic depiction and writer’s ability to present three periods of a character life in a short story. In most of his works the action is short, but it reveals a long period of the hero’s life. Taking this feature into consideration we have the aim to analyze five stories and to prove that short stories may contain the past, present and future prospects are presented. At the same time the content highlights plenty of hero’s life moments, which are of great importance. The attention was paid on the open endings. Cechovas manages to end his stories in a particular way, that for the reader the future of all the heroes in the story is clear.

Mokyklinių istorijos vadovėlių turinio projektavimas ugdymo paradigmų kaitoje Šio darbo tyrimo objektas - VI-ųjų klasių istorijos vadovėlių turinio projektavimas didaktiniu požiūriu. Buvo siekiama ištirti bendrojo lavinimo mokyklos VI-ųjų klasių vadovėlių turinio projektavimą ugdymo paradigmų kaitoje. Iš pradžių buvo analizuojama mokslinė literatūra apie mokyklinių vadovėlių turinio projektavimą bei siekiama atskleisti bendrojo lavinimo mokyklos istorijos vadovėlių pasirinkimo kriterijus, atsižvelgiant į istorijos mokytojų didaktines nuostatas. Tyrimo metu apklausti 123 VI-siose klasėse dirbantys įvairiose Lietuvos respublikos vietovėse mokytojai. Atliekant tyrimą nustatėme, kad vadovėlio pasirinkimą lemia jų atitikimas Bendrosioms programoms. Tačiau nė vieno vadovėlio negalima pavadinti geriausiu, nes nė vienas nelaiduoja vienodai gerai didaktikos principų. Nustatyta, kad šiuolaikiniai istorijos vadovėliai geriausiai laiduoja vaizdumo principo, moksliškumo, prieinamumo principą, tačiau dar pasigendama vidinės integracijos, ugdomojo mokymosi, reflektyvaus mokymosi principų prielaidų. Istorijos vadovėliai laiduoja įvairius mokymo metodus. Palankiausiai įvertino „minčių lietaus“ ir „sąvokų žemėlapių“ metodus naudojamus vadovėliuose. Mokyklose naudojami istorijos vadovėliai labiau laiduoja klasikinius mokymo metodus, nei šiuolaikinius, aktyviuosius metodus. Vertinant VI klasės istorijos vadovėlių turinio projektavimą ergonominiu požiūriu, nustatyta, kad kalbos... [toliau žr. visą tekstą] / The object of this research is planning a subject- matter of manuals for the 6th grade in history in didactics approach. It was important to research the planning subject-matter for secondary school manuals for the 6th grade in history on the background of the transition of educational paradigms. At the beginning scientific literature about the subject –matter of the school manuals was analysed as well as reveal criteria of the choice of the manual in history depending on the teacher’s didactics attitude. 123 teachers of history working in the 6th grade were questioned all over the country during the research. The result revealed that the choice of the manual depends on its correspondence with the Common curriculum. Also it became obvious that none of the manuals could be recognised as the best one for none could guarantee the equal implementation of the principles of the didactics. It was estimated that contemporary manuals for history guarantee pictorial principle, as well as scholarly, accessibility, but still there is a lack of assumptions of internal integration, training learning, and reflective learning. The manuals for history ensure variety of teaching methods. The methods represented in the manuals as brain storming and mind map were assessed most positively. The manuals most frequently used at school ensure the classical teaching methods more often than modern and the active ones. While assessing the planning subject-matter of manuals for 6th grade in history in... [to full text]

It is still recognized as a challenge task while blind and visually impaired people travel outdoor independently, even if there are a number of assistive mobility aids available. In addition to building universal facilities in urban and rural environments for them, it is essential to develop novel mobility assistive technologies and systems to satisfy their increasing demands for mobility. To investigate those demands, an international survey with 106 blind and visually impaired people from 13 countries is undertaken within this work, with regarding to outdoor mobility experiences, usages of mobile devices and collaborative approaches. From the field of Human-Computer Interaction (HCI) and Accessibility, the dissertation focuses on enhancing blind people’s capabilities of acquisition of spatial environmental information from tactile displays. The spatial environmental information, in this study, is in terms of clusters of surrounding obstacles, geographic information on city maps, and information on environmental accessibility. In order to non-visual representation of the clusters of surroundings obstacles detected by a 3D Time-of-Flight (ToF) infrared camera, a portable pin-matrix display with a matrix of 30 x 32 pins is employed and a pre-designed set of tactile obstacle symbols is used to render the properties of obstacles (e.g., type, size). Additionally, aiming at helping blind people access geographic information, a desktop based pin-matrix display (an array of 60 x 120 pins) and a mobile pin-matrix display (an array of 30 x 32 pins) are used to represent a large-scale city map and a location-aware city map, respectively. A set of tactile map symbols rendered with the raised and lowered pins, has been designed for rendering various map features. To allow blind and visually impaired people to acquire information on environmental accessibility, besides a traditional web browser client and a popular smart phone client, an audio-haptic client on a tactile display with 7200 pins is developed. Users are able to create and share collaborative annotations on environmental accessibility across the 3 clients. The proposed approaches about non-visual representation of obstacles and map features by tactile symbols on pin-matrix displays, will contribute to the fields of accessible tactile graphic well, especially in the coming era of affordable pin-matrix displays. Meanwhile, the collaborative approach for improving environmental accessibility will encourage the society to raise the floor of accessibility for all. A number of further studies can be continued based on the current findings within this work, aiming at enhancing mobility aids for blind and visually impaired people gradually.

Thesis (D. Min.)--Southwestern Baptist Theological Seminary, 2006. / Includes abstract. Includes bibliographical references (leaves 141-148).