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The objectives of this dissertation are to measure and calculate surface free energies of soil particles, to understand the mechanical behavior of unsaturated silty sand through first studying the stress-strain relationship, the effects of matric suction and pore water chemistry and second to interpret the behavior by the critical state frame work, to develop a method to predict cone tip resistance in unsaturated soils, and to present the concept of pseudo strain and dissipated pseudo strain energy. Universal Sorption Device (USD) is developed to measure surface free energies of soil particles. The test results on a soil sample shows that specific surface area increased with decreasing particle size. The components of surface free energies and the work of adhesion increased with decreasing particle size. A servo controlled triaxial testing device is developed to test 15.24 cm in height and 7.62 cm in diameter, recompacted specimens of unsaturated soil under varying matric suction and different pore chemistry. During the test, the matric suction is maintained constant. Results from the triaxial drained tests are used for validation of the constitutive models proposed by Alonso et al. (1990). Predictions from the model are in good agreement with experimental results. The critical state model for unsaturated soil is used to calculate cone tip resistance in unsaturated silty sand. The calculated cone tip resistance is used to evaluate the liquefaction potential of unsaturated soils. The results from the stress based liquefaction potential analysis reveal that even in an unsaturated condition soil is susceptible to liquefaction. By applying the pseudo strain concept, it is possible to account for the viscous resistance of water during cyclic loading. The results of undrained cyclic triaxial tests are used to calculate pseudo-strain and dissipated pseudo strain energy. The results of calculated dissipated pseudo strain energy suggest that the effect of initial matric suction is evident. On the other hand, the effect of surface tension increase or decrease due to existence of chemical on the pore water is negligible.

<p>The aim of this essay is to illustrate a modern phenomenon, the Olympic Games, by applying the ideas of Mircea Eliade concerning space, time and myth. This literature study is mainly divided in two parts, one descriptive and one analytic. In the first part Eliade’s ideas and some criticism, which has been pointed against his theoretical approaches as well as his character, are presented. In the second part an analysis is carried out, based on the previously presented ideas and elements essential for the Olympics; the idea of the Olympics, the place, the ceremonies, the competition and the concept of individual idolism.</p><p>I have discussed what seems like gnostic tendencies in Eliade’s ideas, in the sense that both Eliade’s ideas and the concept of Gnosticism argue that knowledge is a necessary condition for salvation, as well as the fact that Eliade and his ideas have not always a pro-Christian approach. I have also shown that incoherency exists in his theoretical approach concerning the manifestation of the sacred.</p><p>I have found that Mircea Eliade’s ideas, with some difficulties, very well can reflect a modern phenomenon such as the Olympic Games. I have also put forth the idea of translating Eliade’s conception of axis mundi into an ideological landscape; the Olympic values become an analogy to axis mundi. Furthermore, I have also shown that modern man in different ways desires to be close to the sacred, and how this fact to some extent may explain people’s devotion to and worship of sport heroes, and thus why not only athletes but also billions of spectators are inclined to attend the Olympics. Finally, I show that, according to Eliade’s ideas, the Olympics might facilitate the process of creating modern myths.</p>

Η μελέτη της φυλοσύνδετης μετάλλαξης wisertsl (1-21.7, 7E) της Drosophila melanogaster αποκάλυψε ότι υπεύθυνο για τους φαινότυπους φαγωμένα/τσιμπημένα φτερά, ελαφρώς ανώμαλα μάτια και τη θερμοευαισθησία είναι το γονίδιο CG32711, που ονομάσαμε wiser (wings scalloped-eyes rough). Το γονίδιο wiser είναι απαραίτητο για τη σωστή ανάπτυξη της Drosophila melanogaster. Η μετάλλαξη wisertsl χαρτογραφείται στη 5΄ ρυθμιστική περιοχή του γονιδίου wiser. Στην ίδια περιοχή χαρτογραφείται και η θανατογόνος μετάλλαξη wiserPL26. Παραπέρα μελέτη του γονιδίου wiser με τη χρήση αυτών των δυο μεταλλάξεων και του διαγονιδίου UAS-wiser αποκάλυψε ότι: α) Οι μεταλλάξεις wisertsl και wiserPL26 ενισχύουν το φαινότυπο των μεταλλάξεων Beadex1 και Serrate1. Το γονίδιο wiser αλληλεπιδρά με τα γονίδια Beadex και Serrate, τα οποία εμπλέκονται στην ενεργοποίηση του Notch μονοπατιού σηματοδότησης κατά μήκος του ραχιοκοιλιακού άξονα του φτερού. Η παρατήρηση αυτή δείχνει, ότι το wiser εμπλέκεται στον προσδιορισμό του ραχιοκοιλιακού άξονα. β) Η μετάλλαξη wisertsl σε ομοζυγωτία μειώνει σημαντικά την έκφραση των διαγονιδίων fringe-lacZ, m8-lacZ, wingless-lacZ, vestigial-lacZ και Distalless-lacZ, αλλάζει το πρότυπο έκφρασης του mβ-lacZ και δεν επηρεάζει την έκφραση του apterous-lacZ στους εμβρυικούς δίσκους του φτερού προνυμφών 3ου σταδίου. Τα αποτελέσματα αυτά έδειξαν, ότι το γονίδιο wiser δρα μετά το γονίδιο apterous και πριν το γονίδιο fringe, που είναι τροποποιητής του υποδοχέα Notch. Επομένως, η δράση του Notch εξαρτάται και από το wiser. γ) Εκτοπική έκφραση του διαγονιδίου UAS-wiser με οδηγό το ap-Gal4, έδειξε ότι διασώζει μερικώς το φαινότυπο apterous- αλλά όχι το φαινότυπο Serrate1. δ) Εκτοπική έκφραση του UAS-wiser με οδηγό το dpp-Gal4, επηρεάζει την έκφραση του wingless-lacZ αλλά όχι των apterous, fringe, mβ, m8, vestigial και Distalless στους εμβρυικούς δίσκους φτερού. ε) Η δημιουργία μιτωτικών κλώνων με το σύστημα FRT/FLP, σε θηλυκά άτομα wiserPL26/+ οδήγησε στη δημιουργία κλώνων +/+ και wiserPL26/wiserPL26 διαφορετικού μέγεθος στους εμβρυικούς δίσκους του φτερού. Οι πρώτοι (+/+), έχουν σημαντικά μεγαλύτερο μέγεθος από τους δεύτερους όταν συμβαίνουν στη περιοχή του εμβρυικού δίσκου που θα δώσει το φτερό του ακμαίου ατόμου. Στα ακμαία θηλυκά οι σωματικοί κλώνοι εκδηλώνονται με το φαινότυπο φαγωμένα φτερά. Σωματικοί κλώνοι παρατηρήθηκαν και στα μάτια των ακμαίων. Τα αποτελέσματα των μιτωτικών κλώνων δείχνουν ότι το γονίδιο wiser εμπλέκεται στον πολλαπλασιασμό των κυττάρων. Όλα τα παραπάνω αποτελέσματα, δείχνουν ότι το γονίδιο wiser είναι απαραίτητο για την ανάπτυξη του φτερού, καθώς εμπλέκεται στο σχηματισμό του ραχιοκοιλιακού άξονα και επηρεάζει τον πολλαπλασιασμό των κυττάρων. / The analysis of the X-linked wisertsl (1-21.7, 7E) mutation in Drosophila melanogaster has shown that responsible for the scalloped phenotype and the temperature sensitivity is the CG32711 gene, which we name wiser (wings scalloped-eyes rough). The gene wiser is essential for Drosophila development. The wisertsl mutation is mapped at the 5′ regulatory region of the gene CG32711. The wiserPL26 lethal mutation is mapped in the same region. Using these two mutations and a UAS-wiser transgene we have shown that: a) The wisertsl and wiserPL26 mutations increase the wing scalloping (phenotype) of the mutations Beadex1 and Serrate1. The genes Beadex and Serrate are implicated in the activation of Notch signaling pathway along the dorsal-ventral axis of the wing. This observation indicates that the wiser gene is involved in determination of dorsal-ventral axis. b) The wisertsl mutation in homozygous condition reduces substantially the expression of fringe-lacZ, m8-lacZ, wingless-lacZ, vestigial-lacZ and Distalless-lacZ transgenes, alters the expression pattern of mβ-lacZ and does not affect the expression of apterous-lacZ transgene in the wing imaginal disc. This indicates that the expression of fringe (a modifier of Notch receptor) is regulated by wiser too. c) Ectopic expression of UAS-wiser by the ap-Gal4 driver partially rescues apterous- but not Serrate1 phenotype. d) Ectopic expression of UAS-wiser by the dpp-Gal4 driver affects the expression of wingless and does not affects the expression of apterous, fringe, mβ, m8, vestigial and Distalless in the wing imaginal disc (revealed by the corresponding -lacZ strains). e) Induction of somatic clones with the FRT/FLP system in wiserPL26/+ mutants led to mitotic +/+ and wiserPL26/wiserPL26 clones of different sizes. The first clones were much larger than the second ones in the territory of wing pouch. Adult females with scalloped wings were also produced. These results indicate that the wiser gene is involved in cell proliferation. All the above findings suggest that the wiser gene is essential for wing development and cell proliferation.

The performance of a horizontal axis marine current turbine is predicted by three numerical methods, vortex lattice method MPUF-3A, boundary element method PROPCAV and a commercial RANS solver FLUENT. The predictions are compared with the experimental measurements for the same turbine model. A fully unsteady wake alignment is utilized in order to model the realistic wake geometry of the turbine. A lifting line theory based method is developed to produce the optimum circulation distribution for turbines and propellers and a lifting line theory based database searching method is used to achieve the optimum circulation distribution for tidal turbines. A nonlinear optimization method (CAVOPT-3D) and another database-searching design method (CAVOPT-BASE) are utilized to design the blades of marine current turbines and marine propellers. A design procedure for the tidal turbine is proposed by using the developed methods successively. Finally, an interactive viscous/potential flow method is utilized to analyze the effect of nonuniform inflow on the performance of tidal turbines. / text

published_or_final_version / Medicine / Master / Doctor of Medicine

Το φυλοσύνδετο γονίδιο wiser (CG32711) είναι απαραίτητο για την ανάπτυξη της Drosophila melanogaster. Η μελέτη μιας θερμοευαίσθητης, θανατογόνου μετάλλαξης που ονομάζεται wisertsl αποκάλυψε ότι το γονίδιο wiser εμπλέκεται μεταξύ άλλων στην ανάπτυξη των φτερών. Η μετάλλαξη wisertsl οφείλεται σε ένα P στοιχείο (7E P) που βρίσκεται 490 bp ανοδικά του σημείου έναρξης της μεταγραφής του γονιδίου wiser. 95 bp καθοδικά του 7E P στοιχείου υπάρχει μια P{lacW} ένθεση υπεύθυνη για τη θανατογόνο μετάλλαξη PL26. Οι μεταλλάξεις wisertsl και PL26 είναι αλληλόμορφα του ίδιου γονιδίου ενώ 12000 περίπου βάσεις ανοδικά του γονιδίου wiser και 490 bp ανοδικά του γονιδίου trf2 υπάρχει μια άλλη P{lacW} ένθεση που είναι υπεύθυνη για τη θανατογόνο μετάλλαξη PL28. Οι PL26 και PL28 δεν δείχνουν συμπληρωματικότητα με τη μετάλλαξη wisertsl όσον αφορά το θανατογόνο φαινότυπο στους 29ºC. Όμως το διαγονίδιο UAS-wiser δε διασώζει το θανατογόνο φαινότυπο του PL28. Τα αποτελέσματα της παρούσας εργασίας αποκάλυψαν ότι: 1) Το γονίδιο wiser αλληλεπιδρά με το γονίδιο dpp. Εκτοπική έκφραση του διαγονιδίου (UAS wiser) υπό τον έλεγχο του οδηγού στελέχους apGAL4, μειώνει την έκφραση του dpp στην περιοχή του εμβρυικού δίσκου που θα δώσει τμήμα του θώρακα (notum). 2) Σε ομόζυγα wisertsl άτομα η έκφραση των γονιδίων dpp, dad, omb και salm (όπως αποκαλύπτεται από την έκφραση των αντίστοιχων –lacZ διαγονιδίων) μειώνεται στον εμβρυικό δίσκο του φτερού. Τα παραπάνω γονίδια είναι απαραίτητα για την ανάπτυξη του προσθοπίσθιου άξονα του εμβρυικού δίσκου του φτερού που σημαίνει ότι και το γονίδιο wiser εμπλέκεται στο σχηματισμό του. 3) Το γονίδιο wiser αλληλεπιδρά με το γονίδιο Notch (N) καθώς N wisertsl /wisertsl θηλυκά έχουν εντονότερα φαγωμένα φτερά. 4) Οι μεταλλάξεις wisertsl και PL28 είτε αφορούν και οι δύο το γονίδιο wiser ή η PL28 αφορά το γονίδιο trf2 που σημαίνει ότι και αυτό εμπλέκεται στο σχηματισμό του φτερού. / The X- linked wiser (CG32711) gene is a vital gene for the development of Drosophila melanogaster. The study of a temperature sensitive lethal mutation, named wisertsl, revealed that the wiser gene is implicated among others in the development of wings. The wisertsl mutation is due to a wild P element (7E P) located 490 bp upstream of the presumed transcription start site of the gene wiser at the region 7Ε. 95 bp downstream of the 7E P element is located a P{lacW} responsible for the lethal mutation PL26 and ~ 12000 bp upstream of the gene wiser and 490 bp upstream of the gene trf2 exists another P{lacW} insertion which is responsible of the lethal mutation PL28. The mutations PL26 and PL28 do not show complementation with the wisertsl mutation as regards the lethal phenotype at 29°C. However, while the transgene UAS-wiser saves the lethal phenotypes of wisertsl and PL26 it does not save the lethal phenotype of the mutation PL28. The present data study revealed that: 1) The wiser gene interacts with the dpp gene. Ectoping expression of the UAS wiserCDS construct under the control of apGAL4 driver, reduced the dpp expression (revealed by dpp-lacZ) in the notum territory of the wing imaginal disc. 2) In the homozygous wisertsl individuals the expression of dpp, dad, salm and omb genes (revealed by the corresponding -lacZ strains) is reduced in the wing imaginal disc. The above genes are implicated in the development of the anterior-posterior (A/P) axis of the wing imaginal disc. 3) The wiser gene interacts with the Notch (N) gene. N wisertsl/wisertsl females have stronger notching phenotype. 4) The induction of mitotic clones revealed that the mutation PL28 either concerns an enhancer of the wiser gene or the gene trf2. At the late case the gene trf2 must affect the development of the wings as well.

This paper describes two experiments, each of which investigated the impact of stress on human episodic memory. All participants watched narrated slide shows containing emotional and neutral information. Experiment 1 demonstrated that pre-learning exposure to a psychological stressor (the Trier Social Stress Test or "TSST"; Kirschbaum, Pirke &amp; Hellhammer, 1993) preserved or enhanced memory for emotional aspects of the slide show, but impaired memory for neutral aspects of the slide show. Moreover, stress exposure disrupted memory for information that was visually and thematically central to the slide show. Memory for peripheral information, on the other hand, was unaffected by stress. Experiment 2 replicated these results and extended them to a similar paradigm, where participants viewed separate emotional and neutral slide shows, and saliva was tested for the stress hormones cortisol and norepinephrine. Similar to the results of Experiment 1, stress disrupted memory for the neutral slide show, but enhanced memory for the emotional slide show. Salivary cortisol levels at retrieval were negatively correlated with memory for the neutral slide show. These results are consistent with theories invoking differential effects of stress on brain systems responsible for encoding and retrieving emotional memories (the amygdala) and non-emotional memories (e.g. the hippocampal formation, frontal cortex), and inconsistent with the view that memories formed under high levels of stress are qualitatively the same as those formed under ordinary emotional circumstances. These data, which are also consistent with results obtained in a number of studies using animals and humans, have implications for the traumatic memory debate and theories regarding human memory.

A tool path generation method for sculptured surfaces defined by triangular meshes is presented in this thesis along with an algorithm that helps determine the best type of cutter geometry to machine a specific surface. Existing tool path planning methods for sculptured surfaces defined by triangular meshes require extensive computer processing power and result in long processing times mainly since surface topology for triangular meshes is not provided. The method presented in this thesis avoids this problem by offsetting each triangular facet individually. The combination of all the individual offsets make up a cutter location surface. A single triangle offsetting results in many more triangles; many of these are redundant, increasing the time required for data handling in subsequent steps. To avoid the large number of triangles, the proposed method creates a bounding space to which the offset surface is limited. The original surface mesh describes the bounding surface of a solid, thus it is continuous with no gaps. Therefore, the resulting bounding spaces are also continuous and without gaps. Applying the boundary space limits the size of the offset surface resulting in a reduction in the number of triangular surfaces generated. The offset surface generation may result in unwanted intersecting triangles. The tool path planning strategy addresses this issue by applying hidden-surface removal algorithms. The cutter locations from the offset surface are obtained using the depth buffer. The simulation and machining results show that the tool paths generated by this process are correct. Furthermore, the time required to generate tool paths is less than the time required by other methods. The second part of this thesis presents a method for selecting an optimal cutter type. Extensive research has been carried out to determine the best cutter size for a given machining operation. However, cutter type selection has not been studied in-depth. This work presents a method for selecting the best cutter type based on the amount of material removed. By comparing the amount of material removed by two cutters at a given cutter location the best cutter can be selected. The results show that the optimal cutter is highly dependent on the surface geometry. For most complex surfaces it was found that a combination of cutters provides the best results.

One of the most essential objectives in WSNs is to determine the spatial coordinates of a source or a sensor node having information. In this study, the problem of range measurement-based localization of a signal source or a sensor is revisited. The main challenge of the problem results from the non-convexity associated with range measurements calculated using the distances from the set of nodes with known positions to a xed sen- sor node. Such measurements corresponding to certain distances are non-convex in two and three dimensions. Attempts recently proposed in the literature to eliminate the non- convexity approach the problem as a non-convex geometric minimization problem, using techniques to handle the non-convexity. This study proposes a new fuzzy range-free sensor localization method. The method suggests using some notions of Euclidean geometry to convert the problem into a convex geometric problem. The convex equivalent problem is built using convex fuzzy sets, thus avoiding multiple stable local minima issues, then a gradient based localization algorithm is chosen to solve the problem. Next, the proposed algorithm is simulated considering various scenarios, including the number of available source nodes, fuzzi cation level, and area coverage. The results are compared with an algorithm having similar fuzzy logic settings. Also, the behaviour of both algorithms with noisy measurements are discussed. Finally, future extensions of the algorithm are suggested, along with some guidelines.