In this report a comparison is made between four frequently encountered resampling algorithms for particle filters. A theoretical framework is introduced to be able to understand and explain the differences between the resampling algorithms. This facilitates a comparison of the algorithms based on resampling quality and on computational complexity. Using extensive Monte Carlo simulations the theoretical results are verified. It is found that systematic resampling is favourable, both in resampling quality and computational complexity.

Gardens played a significant role in the lives of European peoples living in the thirteenth and fourteenth centuries. By producing texts in which gardens and other cultivated landscapes are used as symbol and setting, medieval writers provide us with the opportunity to gain insight into the sociocultural conventions associated with these spaces in the late medieval period. By building our understanding of medieval horticulture through an examination of historical texts, we position ourselves to achieve a greater understanding into the formation of contemporary cultivated literary landscapes and their attendant conventional codes. This study provides a map of current medieval garden interpretation, assessing the shape and validity of recent literary criticism of this field. With a focus on the hortus conclusus (the walled pleasure garden) and arboricultural spaces (including hunting and pleasure parks), this study provides an historicist reinterpretation of horticultural landscapes in Chaucer’s Troilus and Criseyde, Sir Orfeo, and Sir Gawain and the Green Knight, furthering our understanding of the authors’ use of such conventionally-coded spaces in these canonical romances.

<p>Heterochromatin, or condensed chromatin, is a transcriptionally repressive form of chromatin that occurs in many eukaryotic organisms. At its natural locations, heterochromatin is thought to play important roles in genome organization as well as gene expression. Just as important is the restriction of this repressive form of chromatin to appropriate regions of the genome. In the budding yeast <italic>Saccaromyces cerevisiae</italic>, domains of condensed, transcriptionally silenced chromatin are found at telomeres and at the silent-mating type cassettes, <italic>HML<italic/> and <italic>HMR</italic>. At these locations, a complex of Silent Information Regulator (SIR) proteins gets recruited to DNA through discrete silencer elements. Once recruited, the Sir protein complex then spreads along chromosomes in a step-wise manner. This process results in the silencing of gene expression. It is unclear whether silenced chromatin is established in the same manner at different genomic locations. Understanding how silenced chromatin is formed is important for determining how these chromatin structures are regulated.</p><p>To better understand how silenced chromatin is established in different genomic contexts, I used chromatin immuoprecipitation to follow the rate of silenced chromatin formation at different locations. The rates of Sir protein assembly were compared at two locations, telomere VI-R and <italic>HMR</italic>. I discovered that the silencers at these two locations were equally proficient at recruiting Sir proteins. However, the rate of Sir protein assembly onto nucleosomes was far more rapid at <italic>HMR</italic> than at the telomere VI-R. Furthermore, the rate of Sir protein assembly was more rapid on one side of the <italic>HMR-E</italic> silencer at <italic>HMR</italic> than the other. Moreover, insertion of the <italic>HMR-E</italic> silencer adjacent to the telomere VI-R significantly improved the rate of Sir protein assembly onto nucleosomes. Additionally, observations that the association of Sir protein occurs simultaneously across several kilobases at <italic>HMR</italic> and that silencing at <italic>HMR</italic> is insensitive to co-expression of wild-type and catalytically inactive Sir2 proteins suggest that <italic>HMR-E</italic> enables the assembly of silenced chromatin in a non-linear fashion. These results suggest that <italic>HMR-E</italic> functions to both recruit Sir proteins and promote their assembly across several kilobases.</p><p>In addition to the <italic>HMR-E</italic> silencer, <italic>HMR</italic> is also characterized by the presence of a second auxiliary <italic>HMR-I</italic> silencer and a tRNA gene that functions as a boundary element to restrict the spread of silenced chromatin. I used chromatin immunoprecipitation to determine how each of these regulatory elements contribute to the steady-state levels of Sir protein association with chromatin. Consistent with a role for <italic>HMR-E</italic> beyond recruitment, I discovered that the <italic>HMR-E</italic> silencer alone promoted higher levels of Sir proteins on nucleosomes compared to the telomere VI-R. The levels of Sir protein association with <italic>HMR</italic> were further elevated by the <italic>HMR-I</italic> silencer, even though this silencer does not recruit Sir proteins on its own and does not contribute to any of the known functions of silenced chromatin at <italic>HMR</italic>. Additionally, although the tRNA gene did block the spread Sir proteins, I discovered that the capacity for Sir proteins to spread beyond a few kilobases was severely limited even in the absence of the boundary.</p><p>The results of this thesis work provide new insights into the mechanisms of silenced chromatin establishment and regulation in budding yeast. I show here that the capacity of Sir proteins to assemble onto nucleosomes is inherently limited. Additionally, silencers vary in their ability to promote this assembly. I conclude that the silencer is a key factor in determining the relative size, efficiency, and location of silenced chromatin domains in the cell.</p> / Dissertation

Abstract: Instead of assuming that sixteenth-century poetry is a form of transcendence, and instead of defining poetry as an expression of inner life or character, this dissertation argues that there are ways to interpret poetry as a tool that helped sixteenth-century subjects understand and process embodied experience. How do we know that sixteenth-century poetry was a function of the material world and the body? The evidence is in the word selections, themes, and tropes created by poets themselves. By closely examining their writings, we can trace the negotiations between sixteenth-century poetic traditions, senses, and the material world. I explore these negotiations through three sixteenth-century poets whose works may be considered paradigmatic of the larger cultural movements that shaped their world: Sir Thomas Wyatt, the diplomat and courtier-poet in the reign of Henry VIII; Anne Vaughan Lock, a Marian exile who translated Calvin and published devotional poetry at the beginning of the reign of Elizabeth I; and William Shakespeare, whose sonnet sequence published in 1609 responded to Elizabethan cultural arts at a time of energy and change. The three poets engaged in this project are distinct in class, gender, and history, and thus, each chapter is a case study that surveys embodiment in a unique context. But the reason the three poets are viewed together (and the tie that binds them) is that they all wrote serial poems, or verse sequences. When compared across the project, important connections emerge about the cognitive power of serial poems. I argue that verse sequences are dexterous as well as able to perform cognitive "heavy lifting." Whether it was Vaughan Lock and Wyatt who dilated scriptural exemplars and carved space for emerging evangelical ideas, or Shakespeare, who much more clearly wrote inventive verse, sixteenth-century writers used the sequence to test new possibilities and integrate prior knowledge. In this diachronic reading of poetic embodiments, we can begin to see verse sequences as a technology that merges compelling perceptual observation with high abstraction, and that allows for opposing ideas to take place across the text, resolving rigid binaries and synthesizing opposites. Although my project attempts to view the poets together, each chapter provides evidence of significant differences across sixteenth-century poets. Although Wyatt and Vaughan Lock both utilized serial poems to test evangelical beliefs regarding conscience and penitence, they signal opposing impulses when it comes to gendered power. Moreover, Shakespeare's sonnets are more ostensibly amatory than religious in their overall intent. Shakespeare's metaliterary discourses, moreover, mobilized the serial format as an even more reflexive form. The project may be a skeletal map of the space between the evangelical procedures of conscience (which were themselves very reflexive) and Shakespearean procedures of mind. By comparing these differences, we may cast light on the ways in which psalm paraphrase (as a mode and a sequential format) influenced English amatory verse sequences. The dissertation works to address unstudied connections between diverse poets from the period of Henry VIII through the early reign of James I. But the dissertation also forges new routes in Renaissance studies, by proposing directions and methods for studying literary embodiment. I believe that sixteenth-century embodiment is best viewed through the lens of religious history and print technology. Moreover, I argue that the study of sixteenth-century embodiment should also incorporate contemporary historical ideas about the mind. By engaging both New Historicism and the discourse of embodied cognition from neuroscience, finally, the project creates a comparative view of cognition, translating between empirical methods and historicist techniques in English studies. / text

This thesis investigates the development of medical research at the Otago Medical School in Dunedin, New Zealand under Sir Charles Hercus, Dean from 1937-1958. It also explores his interest and participation in research from his student days and the years before becoming Dean, as well as the influence of the First World War on his career. The study draws upon unpublished material in New Zealand archives and a collection of student projects investigating public health issues. Hercus, as Professor of Public Health and Bacteriology incorporated these projects into the curriculum in the early 1920s. The thesis uses many original papers published in scientific and medical journals by Hercus and his colleagues at the School. Building on a base of archival material including contemporary newspaper accounts, which have lately become available on the Papers Past website, this thesis draws together the individual disease studies undertaken by other thesis writers to give an account of Hercus’s achievements in fostering medical research. A key finding of this thesis is that Hercus was instrumental in building up the research capability of the School. He accomplished this through his own investigations and by helping to establish the New Zealand Medical Research Council. The thesis illustrates the multitude of studies that Hercus undertook personally or facilitated others to pursue, beyond the elimination of endemic goitre, for which he perhaps is best known. Another outcome of this study is an understanding of the difficult path that scientists faced in the early years of the twentieth century in New Zealand if they wished to carry out research. This thesis follows the origins of the Department of Scientific Research in the 1920s and the frequent collaboration Hercus made with scientists outside of the School. It will also demonstrate Hercus’s compassion and foresight in employing several Jewish refugee doctors as researchers at the School, who brought expertise into the research programmes. The era was one of great interest in improving the health and wellbeing of a generation affected by wars and deprivation caused by them. A key finding of this thesis is that researchers at the School took steps to mitigate these through making New Zealand more self-sufficient in foodstuffs and to improve the national diet. As well, Hercus lobbied for the establishment of a School of Physical Education within the university to improve the physical fitness of the population.

No description available.

Στην παρούσα διδακτορική διατριβή, διερευνήθηκε η συμπεριφορά μονωτήρων πορσελάνης και μονωτήρων πορσελάνης με επικάλυψη από RTV SIR, σε πραγματικές και εργαστηριακές συνθήκες, με μετρήσεις του ρεύματος διαρροής. Στην περίπτωση των μετρήσεων σε πραγματικές συνθήκες, με την χρήση κατάλληλου εξοπλισμού, κατέστη δυνατή η συνεχής καταγραφή της συμπεριφοράς δώδεκα μονωτήρων πορσελάνης 150kV, οι οποίοι αποτελούσαν ενεργές συνιστώσες δύο υποσταθμών του Συστήματος Μεταφοράς Κρήτης. Από αυτούς σε δέκα είχαν τοποθετηθεί επικαλύψεις από RTV SIR. Παράλληλα πραγματοποιήθηκαν και μετεωρολογικές μετρήσεις, σε συγχρονισμό με αυτές του ρεύματος διαρροής, δίνοντας την δυνατότητα συσχέτισης των μετεωρολογικών παραμέτρων με την αντίστοιχη συμπεριφορά των μονωτήρων. Οι μετρήσεις του ρεύματος διαρροής ανέδειξαν δύο περιόδους δραστηριότητας. Στην περίπτωση των μονωτήρων πορσελάνης η περίοδος αιχμής καταγράφεται στο τέλος της καλοκαιρινής περιόδου, από τον μήνα Αύγουστο μέχρι και τον Οκτώβριο. Τον υπόλοιπο χρόνο καταγράφεται δραστηριότητα, ιδιαίτερα την άνοιξη, σε σημαντικά χαμηλότερα επίπεδα όμως. Η συμπεριφορά αυτή είναι σε συμφωνία με την μηνιαία κατανομή των σφαλμάτων λόγω ρύπανσης στο Σύστημα Κρήτης, την περίοδο 1969 – 2005. Αντίθετα, στην περίπτωση των μονωτήρων με επικάλυψη από RTV SIR, την περίοδο από τον Αύγουστο μέχρι και τον Οκτώβριο, κατεγράφησαν εξαιρετικά χαμηλά ως και μηδενικά επίπεδα δραστηριότητας. Για τα υλικά αυτά, η αιχμή της επιφανειακής δραστηριότητας καταγράφεται κατά την χειμερινή περίοδο. Βέβαια πρέπει να σημειωθεί ότι ακόμη και τότε, η δραστηριότητα στην επιφάνεια των επικαλύψεων από RTV SIR είναι σαφώς ασθενέστερη σε σχέση με αυτήν των μονωτήρων πορσελάνης, το αντίστοιχο χρονικό διάστημα. Η ταυτόχρονη καταγραφή των μετεωρολογικών παραμέτρων ανέδειξε ως παράμετρο κλειδί τον παρατηρούμενο μηχανισμό ύγρανσης σε κάθε περίοδο. Η καλοκαιρινή αιχμή των μονωτήρων πορσελάνης αποδίδεται στην υγροσκοπική συμπεριφορά των ρύπων και στον μηχανισμό της συμπύκνωσης. Είναι σημαντικό ότι οι δύο αυτοί μηχανισμοί δεν μπορούν να μεταβάλουν την κατάσταση της επιφάνειας, ενώ προσβάλλουν το συνολικό μήκος ερπυσμού. Έτσι απουσία βροχοπτώσεων, ο φυσικός καθαρισμός των μονωτήρων το καλοκαίρι είναι δύσκολος, επιτρέποντας την προοδευτική συγκέντρωση της κρίσιμης ποσότητας ρύπανσης. Αντίθετα στους μονωτήρες με RTV SIR, παρά την παρουσία υγρασίας, διατηρείται η υδρόφοβη συμπεριφορά της επιφάνειας, η οποία επιβάλει τελικά την καταστολή της επιφανειακής δραστηριότητας. Αντίθετα τον χειμώνα, η εμφάνιση ασθενών βροχοπτώσεων μπορεί να οδηγήσει σε μεταβολή της κατάστασης της επιφάνειας των μονωτήρων. Στην περίπτωση της πορσελάνης προκύπτει ο καθαρισμός αυτής, ενώ στις επικαλύψεις από RTV SIR, όπου ο καθαρισμός είναι δυσκολότερος, παρατηρείται απώλεια της επιφανειακής υδροφοβίας, με αποτέλεσμα την καταγεγραμμένη δραστηριότητα. Είναι πάντως σημαντικό ότι σε κάθε περίπτωση, τα επίπεδα επιφανειακής δραστηριότητας στις επικαλύψεις από RTV SIR ήταν σαφώς χαμηλότερα από αυτά των μονωτήρων πορσελάνης. Στα πλαίσια των μετρήσεων σε πραγματικές συνθήκες, κατέστη δυνατή και η καταγραφή στιγμιότυπων του ρεύματος διαρροής. Στην περίπτωση των μονωτήρων πορσελάνης, προέκυψε ότι το απαιτούμενο ρεύμα για τον σχηματισμό ξηρών ζωνών, εξαρτάται από τον μηχανισμό ύγρανσης. Στην περίπτωση μηχανισμών όπως η συμπύκνωση, ένα ρεύμα της τάξης των 2mA αρκεί. Αντίθετα στην περίπτωση των βροχοπτώσεων έχουν καταγραφεί ρεύματα της τάξης των 15mA, χωρίς σημάδια ανάπτυξης ξηρών ζωνών. Η ανάπτυξη ξηρών ζωνών υποδηλώνεται στην κυματομορφή του ρεύματος από την εμφάνιση διαστημάτων μηδενικού ρεύματος σε κάθε ημιπερίοδο, τα οποία μάλιστα μεσολαβώντας μεταξύ των διαδοχικών εκκενώσεων υποδεικνύουν την ανεξαρτησία αυτών. Τα μη γραμμικά χαρακτηριστικά του ρεύματος στην περίπτωση αυτή αντικατοπτρίζονται στην εμφάνισης μιας συνιστώσας του ρεύματος στα 150Hz. Αυτά ισχύουν για το εύρος των τιμών ρεύματος που κατεγράφησαν στην περίπτωση αυτή (14mA<ILC<140mA). Αντίστοιχα χαρακτηριστικά προκύπτουν και στην περίπτωση των μονωτήρων με επικάλυψη από RTV SIR. Επιπλέον όμως στην περίπτωση αυτή, κατεγράφησαν εκκενώσεις που δεν σχετίζονται με ξηρές ζώνες, αλλά περισσότερο με το ενδεχόμενο διατήρησης υδρόφοβης συμπεριφοράς για τμήματα της επιφάνειας του μονωτήρα. Επιπλέον η αλλοίωση της κυματομορφής του ρεύματος είναι εντονότερη στην περίπτωση αυτή, κάτι που συνεπάγεται υψηλότερα επίπεδα στην αρμονική των 150Hz. Παράλληλα με τις μετρήσεις σε πραγματικές συνθήκες, οι συνθέσεις των υλικών RTV SIR που χρησιμοποιήθηκαν, αξιολογήθηκαν και σε εργαστηριακές συνθήκες. Πραγματοποιήθηκαν δύο δοκιμές σε θάλαμο υδατονέφωσης άλατος, όπου οι συνθήκες καταπόνησης μοιάζουν με το ενδεχόμενο της βροχόπτωσης σε πραγματικές συνθήκες. Από την συμπεριφορά των υλικών στις συγκεκριμένες συνθήκες και τις μετρήσεις που έγιναν, προκύπτει ότι οι συνθέσεις με ΑΤΗ είναι περισσότερο ανθεκτικές, τόσο όσον αφορά το φαινόμενο corona (υδρόφοβη επιφάνεια), όσο και την καταπόνηση από ξηρές ζώνες, στην περίπτωση απώλειας της υδροφοβίας, σε σχέση με αυτές όπου χρησιμοποιείται silica. Η διαφορά οφείλεται στον τρόπο προστασίας που προσφέρει ο κάθε τύπος πρόσμιξης. Πάντως πρέπει να σημειωθεί ότι είναι απαραίτητη η περαιτέρω εργαστηριακή διερεύνηση της επίδρασης του τύπου της πρόσμιξης, όσον αφορά την επίδραση τόσο των εκκενώσεων corona όσο και των εκκενώσεων ξηρών ζωνών. / In the present study the performance of porcelain and RTV SIR coated porcelain insulators has been investigated in field and laboratory conditions, by leakage current measurements. In field conditions, by the use of the appropriate equipment it was possible to continuously monitor a group of twelve 150kV porcelain insulators, installed in two high voltage substations, of the Transmission System in Crete. Ten of them were coated with RTV SIR. In addition simultaneous measurements of meteorological parameters were performed, allowing the correlation of the LC measurements to the environmental conditions. The leakage current measurements performed indicated two periods of intense surface activity. In the case of porcelain, the summer period and especially the months From August to October, represent the period of intense surface activity. During the rest of the year the recorded LC levels are remarkably lower. This monthly distribution comes in agreement with the observed pollution flashovers distribution, for the period 1969-2005. The opposite activity distribution is observed for the RTV SIR coated insulators. In this case the levels of surface activity in the summer period are remarkably low and the period of intense activity for the coatings is observed during the winter. It is worth mentioning however that even in this case the levels of activity are remarkably lower than the corresponding levels in the case of porcelain, for the same time period. The opposite behavior of porcelain and coated porcelain insulators can be correlated to the environmental conditions and especially the wetting mechanism present. During the summer, insulator wetting is possible as the result of two mechanisms, the hydroscopic behavior of the pollution layer and condensation. Both mechanisms are capable of wetting the total leakage creepage distance, without cleaning the insulators surface in the same time. As a result a critical amount of pollution can be formed on the insulator surface, considering also the low levels of precipitation. So in the case of porcelain the formation of surface conductivity is possible in contradiction to the RTV SIR coated insulator, where the formed surface hydrophobicity is maintained. On the other hand during the winter, light precipitation can support the development of surface activity, since it is possible to disturb the surface condition. In the case of porcelain this will result to the cleaning of the surface. However in the case of RTV SIR coatings a loss of hydrophobicity is observed which allows the development of surface activity, considering also that cleaning is more difficult in this case. It is worth noticing however that in all cases the observed activity on the RTV SIR coated insulators is remarkably lower than the corresponding activity in the case of uncoated porcelain insulators. The leakage current waveforms for finite time periods are also included in the information provided by the field measurements performed. In the case of porcelain insulators, the analysis of the corresponding waveforms indicated that the current required for the formation of dry bands depends on the wetting mechanism present. In the case of mechanisms such as condensation, a current in the range of 1 – 2mA is capable to support the formation of dry bands. However in the case of precipitation the necessary current is higher, reaching a level of 15mA. Further the formation of dry bands is reflected to the leakage current waveform by zero current periods which are observed between the current conduction periods. This behavior indicates that the observed activity can be considered as a sequence of independent current pulses. Additionally the FFT analysis correlates the non linear current behavior to an increased 150Hz component. These characteristics have been traced in all the waveforms recorded, in the range from 14mA to 150mA. In the case of RTV SIR coated insulators the recorded waveforms are in large extent similar to the waveforms on the porcelain insulators. However additional phenomena, correlated with the existence of areas which maintain the hydrophobic behavior. In addition the non linear behavior is enhanced in this case, something that results in higher levels of a current component at 150Hz. The performance of the employed RTV SIR coatings was also investigated in laboratory conditions. Two tests were performed in a salt fog chamber, were the stress conditions are similar to the conditions observed in the case of light rain. The material performance observed and the corresponding measurements performed in both tests, indicate that the formulations tested, the endurance of the ATH filled coatings is higher than the silica filled, both in the case of corona and dry band discharge stress. The difference observed can be correlated with the action of each filler type. However the influence of the filler action needs to be further investigated.

No description available.

Anthony van Dyck's contemporary vision of sovereignty and knighthood made him the principal image-maker in England during the 1630s. His portraits of Charles I exemplified the Arcadian realm and philosophies held at court, as well as complying with the artistic and historical traditions of English painting. As a celebration of Monarchy by Divine Right, Van Dyck's portrayals of the Sovereign summarize the philosophical concepts of knighthood expressed in the Platonic Love theory and the Order of the Garter. Charles I was Defensor Fides, Pater Patriae, the suitor to his lady, and the courtly gentleman--all roles of the knight. Beyond his stylistic influence, Van Dyck's foremost contribution was the endowment of maiestas to the royal image, followed by divine apotheosis for posterity. A better understanding of Van Dyck's Charles as the Garter Sovereign leads us to modify our perception of the artist, since he became the painter of contemporary British history.

No description available.