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Effect of Alkalinity in Irrigation Water on Selected Greenhouse Crops. (August 2004) Luis Alonso Valdez Aguilar, B.S., Universidad Aut??noma de Nuevo Le??n, Mexico; M.S., Universidad Aut??noma Chapingo, Mexico Chair of Advisory Committee: Dr. David Wm. Reed Bicarbonate (HCO3-) and carbonate (CO32-) are the most important ions that determine alkalinity. When the carbonates accumulate in a growing medium, the growing medium solution pH reaches levels that cause plant growth inhibition, which is caused primarily by the transformation of soluble forms of Fe into insoluble forms. The general objective of this research was to provide information about the limits of tolerance to alkalinity in ornamental plants, and to study the interaction of ions such as ammonium (NH4+) and nitrate (NO3-) on the response of plants to alkalinity, as well as the effect of the counter-ions potassium (K+), sodium (Na+), cesium (Cs+), ammonium (NH4+) and rubidium (Rb+). The maximum SPAD index was estimated to occur at 0 mM of NaHCO3 in chrysanthemum, mini-rose, and hibiscus ??Bimini Breeze?? and ??Mango Breeze??. For vinca it was set at 2.64 mM. A 15% decrease from the maximum SPAD index was considered the threshold to declare the toxic concentration of NaHCO3, which was calculated based on the maximum SPAD index predicted by the models. The toxic concentration of NaHCO3 was set at 4.1, 1.1, 6.7, 3.1, and 6.3 mM of NaHCO3 in chrysanthemum, mini-rose, vinca, and hibiscus ??Mango Breeze?? and ??Bimini Breeze??, respectively. Hibiscus ??Bimini Breeze?? was considered tolerant to alkalinity, due to increased Fe-reduction capacity and acidification of the growing medium. In the hydroponic experiment, results showed that the NH4+:NO3- ratio altered the response of sunflower plants to alkalinity. Sunflower plants grew better in solutions containing 5 mM NaHCO3 prepared with a 0.25:0.75 NH4+:NO3- ratio. This was possible due to the reaction of NH4+ with the HCO3-, which reduced its buffering capacity. The response to HCO3--induced alkalinity was modified by the counter-cation of HCO3-. In bean plants, at low-to-intermediate levels of Na+ and HCO3- induced approximately same growth decrease. At high concentration, Na+ induced a decrease on shoot growth that exceeded the toxic effects of HCO3-. Thus, the toxic effect of Na+ is higher than that of HCO3- when its concentration is high. Rubidium was extremely toxic at concentrations of 7.5 mM.

Η παρούσα διπλωματική προτείνει μια hardware υλοποίηση για κρυπτογράφηση μηνυμάτων βασισμένη στο πρότυπο ασφαλείας Galois/Counter Mode (GCM). O αλγόριθμος κρυπτογράφησης Galois/Counter Mode (GCM) εκδόθηκε από τον οργανισμό National Institute of Standards and Technology (NIST) τον Νοέμβριο του 2007. Σε συνεργασία με τον μηχανισμό πιστοποίησης μηνυμάτων, υλοποιείται το συνολικό πρότυπο GCM για online λειτουργία. Στο Κεφάλαιο 1, αρχικά γίνεται μια σύντομη ιστορική αναδρομή στον τομέα της κρυπτογραφίας. Στην συνέχεια παρουσιάζονται οι λόγοι που οδήγησαν στην δημιουργία αυτού του προτύπου ασφαλείας. Ακολουθεί μια σύντομη εισαγωγή στον GCM και στους τρόπους με τους οποίος αυτός δουλεύει. Στο τέλος του κεφαλαίου αναφέρονται οι πρακτικές εφαρμογές που έχει η χρήση του G. Στο Κεφάλαιο 2, αρχικά αναφέρονται οι συμβολισμοί και οι βασικές έννοιες που χρησιμοποιούνται στην διπλωματική. Στην συνέχεια, δίνονται συνοπτικές πληροφορίες για το μαθηματικό υπόβαθρο που είναι απαραίτητο για την κατανόηση των εσωτερικών μηχανισμών του GCM. Ακολουθεί η ανάλυση των μαθηματικών συνιστωσών του GCM. Επίσης, παρουσιάζεται το υπόβαθρο των τρόπων λειτουργίας (mode of operation) που υιοθετούνται στον GCM. Τέλος, δίνονται συνοπτικά βασικές πληροφορίες της FPGA πλατφόρμας, Στο Κεφάλαιο 3, γίνεται μια ολοκληρωμένη ανάλυση και μελέτη του Advanced Encryption Standard (AES) και πιο συγκεκριμένα της forward cipher function με υποστηριζόμενο κλειδί 128 bit, καθώς αυτή η διεργασία αποτελεί τον βασικό συμμετρικού κλειδιού block cipher που χρησιμοποιείται στον GCM. Στο Κεφάλαιο 4, πραγματοποιείται η ανάλυση του προτύπου GCM βασισμένη στο τέταρτο recommendation του NIST. Παρουσιάζονται όλοι οι επιμέρους αλγόριθμοι που χρησιμοποιούνται καθώς και ο τρόπος με τον οποίον αυτοί αλληλεπιδρούν και συνεργάζονται για την δημιουργία του GCM αλγορίθμου. Στο τέλος του κεφαλαίου, αναφέρονται οι απαιτήσεις για key και IV που πρέπει να ικανοποιούνται για να θεωρείται ο αλγόριθμος κρυπτογραφικά ισχυρός. Στο Κεφάλαιο 5, αρχικά γίνεται μια top down ανάλυση του GCM. Την ανάλυση αυτή συμπληρώνει η δεύτερη ενότητα στην οποία παρουσιάζεται και αναλύεται η προτεινόμενη αρχιτεκτονική για την hardware υλοποίηση. Στην συνέχεια, δίνεται ο σχεδιασμός των βασικών δομικών στοιχείων του GCM. Στην τελευταία ενότητα παρουσιάζεται η συνολική αρχιτεκτονική του GCM με σκοπό την υλοποίηση για high speed απαιτήσεις. Στο Κεφάλαιο 6, δίνεται μια συνοπτική περιγραφή στα γενικότερα θέματα μια γλώσσας περιγραφής υλικού, και των εργαλείων εξομοίωσης και σύνθεσης. Στο Κεφάλαιο 7, δίνονται τα αποτέλεσμα που προέκυψαν από την εξομοίωση του VHDL κώδικα. Ακολουθούν τα αποτελέσματα της σύνθεσης από δύο διαφορετικές FPGA τεχνολογίες. Στη συνέχεια γίνεται εισαγωγή στον τρόπο με τον οποίο ο μηχανισμός πιστοποίησης και κρυπτογράφησης μηνυμάτων συνεργάζονται για την υλοποίηση του GCM και δίνεται ο τρόπος λειτουργίας του GCM μηχανισμού που υλοποιήθηκε. Ακολουθούν τα αποτελέσματα της εξομοίωσης και σύνθεσης σε δύο διαφορετικές τεχνολογίες καθώς και μια σύγκριση μεταξύ των δύο τεχνολογιών που χρησιμοποιήθηκαν για την σύνθεση. Στο Παράρτημα Α παρουσιάζεται ο τρόπος χρήσης του Xilinx ISE που χρησιμοποιήθηκε για την σύνθεση του VHDL κώδικα για την τεχνολογία Virtex-V. / This thesis proposes a hardware implementation in high speed data rates for encrypting messages based on security standard Galois / Counter Mode (GCM). The encryption algorithm Galois / Counter Mode (GCM) was adopted by the National Institute of Standards and Technology (NIST) in November 2007. In cooperation with the authentication message mechanism, the standard for online GCM mode is fully implemented. The Galois/Counter Mode of Operation (GCM) simultaneously authenticates and encrypts data at speeds that were not previously possible for both software and hardware implementations. In GCM, data integrity is achieved by chaining Galois field multiplication operations while a symmetric key block cipher such as the Advanced Encryption Standard (AES), is used to meet goals of confidentiality.

The Return Home : Mongo Beti's Late OeuvreIn 1991 amid the wave of democracy sweeping Africa, Mongo Beti returned to his native country of Cameroon to continue his literary career after 32 years of exile in France. My dissertation investigates the originality of his homecoming discourse. I explore how this prominent writer's late oeuvre illustrates his struggle to re-discover the country he left decades earlier as well as how his experience of returning shaped a new literary perception. His work after returning home reflects his gradual re-acquaintance with and re-integration into his native country. I argue that at the outset, his perception is initially guided by a backward glance on the past and that his assessment of the present aims at resisting pessimistic representations of Africa. In his later works, however, one cannot but notice the same sentiments of dissatisfaction and disillusion that were based on his first hand experience. To this extent, Mongo Beti's post-return literature can be considered dynamic as it evolved over time. A diachronic approach allowed me to examine his changing perceptions and representations of Africa based on the magnitude of his comprehension of his environment at each point in time. His post-return writing demonstrates a progressive redefinition of some of his previous narrative techniques as regards such elements as political resistance, authoritative narrators, linear unfolding of the plot, time and space, and character development. My analysis also questions the concept of "home" as a place of safety and refuge just as his post-return novels portray exile as an ambiguous state of being in-between worlds, as an expression of a simultaneous connection to the "new old" home and the distant former one abroad. Therefore, there is a shift in Mongo Beti's post-return discourse away from questions of national responsibility and social progress rooted in a consciousness of belonging to a defined community. The conceptual organization of my dissertation is derived from my reading of each of the four texts of the post-return era, and the way they illustrate the author's process of re-discovery of postcolonial Cameroon.

This thesis investigates religious life in Glasgow, Scotland in the sixteenth century. As the first full length study of the town’s Christian community in this period, this thesis makes use of the extant Church documents to examine how Glaswegians experienced Christianity during the century in which religious change was experienced by many communities in Western Europe. This project includes research from both before and after 1560, the year of the Reformation Parliament in Scotland, and therefore eschews traditional divisions used in studies of this kind that tend to view 1560 as a major rupture for Scotland’s religious community. Instead, this study reveals the complex relationships between continuity and change in Glasgow, showing a vibrant Christian community in the early part of the century and a changed but similarly vibrant community at the century’s end. This project attempts to understand Glasgow’s religious community holistically. It investigates the institutional structures of the Church through its priests and bishops as well as the popular devotions of its parishioners. It includes examinations of the sacraments, Church discipline, excommunication and religious ritual, among other Christian phenomena. The dissertation follows many of these elements from their medieval Catholic roots through to their Reformed Protestant derivations in the latter part of the century, showing considerable links between the traditions. This thesis argues that although considerable change occurred through the establishment of a Presbyterian Church polity and the enforcement of new conceptions of Church discipline, many elements of popular devotion remained stable throughout the period. The research in this project challenges many of the traditional narratives of Scottish Reformation historiography. It disputes notions of the decay of the Church in the years previous to the Reformation parliament, and it questions the speed with which the goals of the Reformation were achieved in the town. It also challenges traditional interpretations of the martyrdom of John Ogilvie, a Jesuit executed in the town in 1615. In this way, the dissertation offers an alternative approach to the period that could be applied to research done on other Scottish or European towns.

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Zooplankton play a vital role in the world's oceans in terms of transport of carbon out of the surface layer and providing food for fish. Zooplankton are patchily distributed on all scales, and this has important consequences for both sampling and understanding their role in the ocean. The distribution of zooplankton on different scales forms the focus of this study. Three Atlantic Meridional Transect (AMT) cruises were carried out and data made available from three previous cruises. Zoo plankton data were collected using a combination of vertical nets and using an optical plankton counter (OPC) sampling from the pumped seawater supply. Validation of methods showed that the OPC data could reliably be converted to carbon and numerical abundance estimates for open ocean conditions. Spectral analysis suggested that surface zooplankton heterogeneity followed a power law relationship over several scales. Over the 30 to 1000 km range this was approximately -1, and for smaller and larger scales the slope was reduced. Chlorophyll was less patchy, following temperature and salinity over the same range with a slope of -1.8. Analysis of large scale heterogeneity showed clear latitudinal trends in diversity, particularly evident in the copepod genera, with low diversity at high latitudes. The size structure appeared to be more closely related to the productivity of the area, with high zooplankton biomass associated with larger zooplankton. Regions with similar copepod communities were identified. These were found to be similar to other pelagic regions, but less closely related to watermasses or production regimes. Multiple linear regression of surface zooplankton biomass showed a strong relationship with the physics (temperature and salinity), chlorophyll and the time of day, accounting for 55% of the variability. Use of the regression equations to predict new transects gave R²=0.34. Improvement could be made by dividing the transect into smaller regions. Neural networks gave enhanced predictability (R² = 0.77 for the training set, and R²= 0.47 for the novel set) with a simpler model, although similar variables were important. This study has shown that copepods show latitudinal gradient in diversity, associated with seasonality, and form regions of similarity that do not conform to biogeochemical provinces or the watermasses. Neural networks may be used to predict zooplankton abundance from a few readily available parameters.

Univ., Diplomarbeit--Frankfurt (Main)

Thesis (Ph.D.) - University of Glasgow, 2008. / Ph.D. thesis submitted to the Section of French, Faculty of Arts, 2008. Includes bibliographical references. Print version also available.