Rozprawy doktorskie na temat „Raptor”

During the 1400s and 1500s, noblemen and noblewoman were expected to participate in falconry. Therefore, I was surprised to discover that there was hardly anything written about the ca. 1500 portrait of James IV of Scotland with a Peregrine falcon, extant only in a copy by Daniel Mytens in 1620-1636. What was written was limited to issues of style and attribution of the copy painted by Mytens. There was nothing at all about the falcon or falconry implements represented in the portrait. To understand the function of this portrait, I considered the material culture and physical practices of falconry, the specific habits and characteristics of the falcon, symbolism of falconry in courtly love poetry, the history and culture of animals, the history and economic state of Scotland, and the actual expenses of the practice as recorded in court documents. I argue that the original watercolor portrait of James IV of Scotland with a Peregrine falcon functioned as a marriage portrait. Specifically, the relationship between James and his female falcon in the portrait served to promise a relationship of mutual trust, respect and loyalty between James and his bride-to-be in the future.

In this project, we investigate the performance of Raptor codes as candidatesfor channel coding for the wireless communication between access nodes.Very high data-rates are used, and processing uses more resources than transmission.Therefore, we need fast encoding and decoding algorithms for thechannel coding. Raptor codes have linear encoding and decoding times, andcan have very small overhead if they are properly designed. Hence, they arepossible candidates. We have implemented an encoding and decoding algorithm for Raptorcodes, as well as an environment for simulation. The system requirementsare expressed in terms of delay between the beginning of a transmission andthe successful decoding, and storage required during the transmission and processing.We have evaluated the performance of Raptor codes in terms of delayand storage as a function of system design parameters, in particular the numberof nodes in the network, and the size of the packets. We show that if thesize of the packets is properly chosen, Raptor codes can be useful for the application,and we explain the method for choosing the size of the packets. Wealso provide a way to calculate the delay and the storage for a given systemconfiguration, in order for example to determinate the larger number of nodesor the larger of users such that the delay and the storage are acceptable.

This study documents the 1996 and 1997 autumn migration seasons at Grassy Key for 16 species of raptors (hawks, eagles, and falcons). My results indicate the Florida Keys are a major raptor migration flyway (over 26,000 sightings). I identified factors influencing watch-site location in the Keys. Northbound flights must be included to avoid inflating southbound counts. By removing the "season effect" (natural rise, peak, and wane of raptor numbers during migration), I demonstrate wind has little consistent effect on raptor counts in the Keys. I further demonstrate we do not see more raptors on cold front days than on non-cold front days. However, cold fronts following tropical storms (as in 1996) increase the number of raptors observed for most species. I conducted a nightly roosting survey on Boot Key resulting in near or over 3,000 raptor sightings per season and present a model to predict aerial counts from roosting counts.

Skeletal muscle is the largest organ in the body comprising 40% of total body mass. Skeletal muscle mass is the result of an equilibrium between protein synthesis and protein breakdown. When protein synthesis overcomes protein degradation the result is muscle hypertrophy with increased fiber size. Better understanding of the signaling pathways controlling muscle mass and function is of great importance. Indeed so far there are no therapeutic approaches that can prevent or reduce muscle wasting, as seen in aging and muscular dystrophy. While various studies have identified important regulators of adult skeletal muscle mass, little is known about how these pathways can modulate muscle function. One of the main pathways regulating skeletal muscle is the Akt-mTOR pathway. Under anabolic conditions, mTOR is activated, leading to increased protein synthesis through the phosphorylation of S6K1 and 4EBP1. On the other hand, mTOR activation can also lead to the inhibition of protein degradation through the phosphorylation of Ulk1, which is involved in the autophagosome formation. mTOR assembles into two distinct multiprotein complexes, namely the rapamycin-sensitive complex mTORC1 and the rapamycin-insensitive complex mTORC2. While mTORC2 is mainly involved in cytoskeleton reorganization, mTORC1 plays a role in cell growth and protein synthesis. One of the key members of the mTORC1 is a 150kDa protein called Raptor, which has been shown to be able to recruit mTOR substrates S6K1 and 4EBP1 on mTORC1, promoting their phosphorylation (Hara et al., 2002) (Kim et al., 2002). Mice lacking Raptor only in skeletal muscle from birth show a pronounced myopathy leading to premature death (Bentzinger et al., 2008). However, treating adult mice with the specific mTORC1 inhibitor rapamycin does not lead to a myopathic phenotype and even improves muscle physiology in aged mice (Harrison et al., 2009). So, we wondered what happens if Raptor is deleted in adult skeletal muscle. We, therefore, generated an inducible muscle-specific Raptor knock-out mouse line (HSA-Raptor ko). One month of Raptor deletion in adult muscle does not affect muscle mass or muscle morphology. In addition, also muscle force production is comparable between control and knock-out animals, confirming that at this time point there are no myopathies. Since in literature it has been reported that deletion of Raptor from birth leads to premature death around 5-6 months of age, we decided to monitor mice lifespan and body weight for a longer period after deletion. We observed that body weight during these months is unchanged between wt and Raptor ko mice, so we decided to sacrifice mice 7 months after the beginning of the treatment to assess muscle histology. At this time point, muscles from Raptor ko mice showed signs of a muscle myopathy, with centronucleated fibers, a high number of small and large muscle fibers, central structures and inflammation. In addition, we observed that Raptor knock-out muscles show a huge amount of spontaneous fibrillation spikes at rest, suggesting the presence of denervated fibers. Furthermore, mitochondrial membrane potential and respiratory chain complex activity are impaired upon Raptor deletion. These features result in compromised muscle performance and exercise intolerance. Moreover, while metabolic characteristics upon Raptor deletion shift from oxidative to glycolytic fibers with glycogen accumulation, structural properties reveal the opposite behaviour, with a shift from fast- to slow- twitch fibers. This is likely linked to the increased activity of calcineurin- NFAT pathway seen in Raptor ko muscles. Since understanding the key players in the regulation of muscle mass can be of therapeutic interest, we wanted to understand the role of Raptor during Akt-induced hypertrophy. So, we generate an inducible muscle- specific Akt-Raptor ko mouse line. Akt overexpression results in a strong increase in cross-sectional area of muscle fibers, which is only partially reduced upon Raptor deletion. Moreover, fiber hypertrophy is completely blunted when Akt-Raptor ko mice are treated with the mTORC1 inhibitor, rapamycin. We also found that Akt-Raptor ko mice are significantly weaker than controls, meaning that Akt-induced hypertrophy in the absence of Raptor is not functional anymore. In addition, this effect is not reverted by rapamycin administration, as seen in Akt-S6K1 knock-out mice (Marabita et al., 2016).
I muscoli scheletrici costituiscono il 40% di tutto l’organismo. Il tessuto muscolare è un tessuto molto plastico e dinamico che si adatta in relazione ai diversi stimoli. La massa muscolare è il risultato di un equilibrio tra sintesi e degradazione proteica: una maggior sintesi delle proteine muscolari porta infatti ad ipertrofia mentre una maggior degradazione associata ad una ridotta sintesi ha come conseguenza uno stato atrofico del muscolo. Una migliore conoscenza delle vie di segnale che regolano la crescita e la funzione muscolare diventano di particolare importanza terapeutica per prevenire la perdita di massa associata sia all’invecchiamento, che a diverse patologie, quali ad esempio distrofie e sclerosi. Una delle vie maggiormente implicate nella regolazione della crescita muscolare è la via Akt-mTOR. In condizioni anaboliche, mTOR è attivo e promuove la sintesi proteica attraverso la fosforilazione di S6K1 e 4EBP1. Inoltre, mTOR va anche a bloccare la degradazione proteica attraverso l’inibizione di una proteina che partecipa alla formazione dell’autofagosoma, Ulk1. mTOR esiste sotto forma di due complessi multiproteici: mTORC1, implicato nella crescita cellulare, e mTORC2, che regola la riorganizzazione del citoscheletro. Uno dei componenti principali di mTORC1 è la proteina Raptor, che è in grado di reclutare i substrati di mTORC1, quali ad esempio S6K1 e 4EBP1, promuovendone la fosforilazione (Hara et al., 2002) (Kim et al., 2002). Topi in cui Raptor è assente nel muscolo scheletrico dalla nascita sviluppano una severa miopatia, risultante in una morte prematura degli animali (Bentzinger et al., 2008). Tuttavia, il trattamento di topi adulti con rapamicina, che inibisce selettivamente mTORC1, non porta a patologie muscolari e, anzi, migliora la fisiologia del muscolo di topi anziani (Harrison et al., 2009). Considerando questi risultati contradditori, ci siamo chiesti quale sia il ruolo di Raptor nel muscolo adulto. Abbiamo, quindi, generato un modello murino in cui Raptor viene deleto nel muscolo scheletrico in maniera inducibile. Un mese di delezione di Raptor non ha effetti sulla morfologia o sulla funzionalità del muscolo. Considerando che in letteratura i topi knock-out per Raptor dalla nascita muoiono attorno ai 5-6 mesi, abbiamo deciso di monitorare il peso corporeo e la durata della vita per un periodo di tempo maggiore. Abbiamo notato che, durante questi mesi, il peso rimane invariato tra i topi controllo e i topi knock-out; abbiamo, quindi, deciso di sacrificare gli animali 7 mesi dopo l’inizio del trattamento per controllare l’istologia del muscolo. A questo punto, i muscoli dei topi Raptor ko mostrano segni miopatici, con fibre centronucleate, fibre atrofiche e ipertrofiche, strutture centrali e infiammazione. Inoltre, abbiamo notato che i muscoli knock-out presentano fibrillazioni spontanee e quindi attività elettrica a riposo, suggerendo la presenza di fibre denervate. La delezione di Raptor, inoltre, ha portato ad una severa depolarizzazione mitocondriale e ad una ridotta attività di alcuni complessi della catena respiratoria. Tutti questi effetti sono facilmente collegabili alla significativa debolezza muscolare osservata in questi topi. Dal momento che una più approfondita conoscenza dei mediatori maggiormente implicati nella crescita muscolare può essere di interesse terapeutico, abbiamo deciso di generare una nuova linea murina in cui Akt viene espresso e Raptor deleto solo nel muscolo scheletrico in maniera inducibile al fine di valutare quale sia il ruolo di Raptor nella crescita indotta dall’overespressione di Akt. Nei topi Akt-Raptor ko, l’ipertrofia delle fibre muscolari è solo parzialmente ridotta in confronto a quella osservata nei topi Akt. Incredibilmente, il trattamento con rapamicina significativamente diminuisce la crescita indotta da Akt, anche in assenza di Raptor. Inoltre, i topi Akt-Raptor ko mostrano una ridotta forza muscolare, suggerendo che l’ipertrofia dipendente da Akt in assenza di Raptor non è più funzionale. Quest’effetto non è normalizzato neanche dalla somministrazione di rapamicina, com’era stato visto nei topi Akt- S6K1 ko (Marabita et al., 2016).

Of the 36 diurnal raptor species in North America, 31 (~86%) are either complete or partial migrants. During fall and spring, raptors use "leading lines" or topographic features, such as mountain ranges, rivers, and coastlines that help guide them during their migration, and sometimes are redirected by diversion lines, or barriers that they are hesitant to cross (e.g., large bodies of water). Our objective was to assess the use of mountain ranges and rivers in central and southeastern Arizona by migrating raptors and to determine physical and ecological factors that are important to raptor migration across the United States. We counted migrating raptors in the spring and fall for two years at ten paired count stations in central and southeastern Arizona. Arizona counts were incorporated with counts from across the United States to determine physical and ecological features that influence migration rates. Raptor counts for central and southeastern Arizona averaged 2.0 raptors/hour, and were similar to what is observed at most other counting stations in the Central and Pacific Flyways. Stepwise regression models for the United States indicated counts were negatively related to distance from a diversion barrier and positively related to continuity of elevation. Understanding the factors that influence migrating raptors will inform decisions about environmental modifications and their potential influence on raptor populations. The following appendices are written and formatted to be submitted to journals. Although part of a thesis, they are written in plural to reflect the necessary authorship for journal submission. The first appendix, titled "Assessment of raptor migration corridors in central and southeastern Arizona", will be submitted to the Southwestern Naturalist. The second appendix, title "Assessment of raptor migration corridors in the United States", will be submitted to the Journal of Raptor Research.

We investigate the design of Raptor codes---a class of fountain codes---over Gaussian channels. In this thesis, we prove that there exists no universal choice of input degree distribution or constructing capacity-achieving Raptor codes using mean-LLR, EXIT chart approach. An approach of finding input and output degree distribution jointly is proposed. Through the codes constructed by this approach, we show our approach uniformly outperforms an existing heuristic approach over all Gaussian channels. However, there still exists a gap to channel capacity for Raptor codes constructed by mean-LLR. EXIT chart based approach.

The interrelationships between species composition, resource-use and availability, breeding and competition were studied in two hill habitat raptor communities in a conserved reserve and an unprotected communal land in Zimbabwe in 1995 and 1996. The conserved Lonestar Study Area (LSA) and the unprotected Communal Land Study area (CLSA) had 38 and 31 raptor species, high and normal diversities for the area sizes respectively. An estimated 147 pairs of 21 raptor species bred in 40km² in the LSA compared to only 26 pairs of 22 raptor species per 40km² in the CLSA. Six species (African Hawk Eagle Hieraaetus spilogaster, Black Eagle Aquila verreauxii, Crowned Eagle Stephanoaetus coronatus, Little Banded Goshawk Accipiter badius, Barn Owl Tyto alba,and Barred Owl Glancidium capense made up 69% of breeding raptors in the LSA, while African Hawk Eagles, Little Banded Goshawks, Barn Owls and Barred Owls made up 58% of the breeding raptors in the CLSA. The abundance of Black, Crowned and African Hawk Eagles in the LSA was linked to abundant hyrax, Heterohyrax brucei and Procavia capensis and juvenile bushbuck Tragelaphus prey, and the high reproduction rates of Natal Francolin Francolinus natalensis (0.7 per ha when not breeding). Little Banded Goshawk and Barn Owl abundances were linked to their ability to change prey preferences according to prey availability. A fairly high rate of breeding attempts by eagles in the LSA in both years (60 - 76% of all pairs per year)was probably also linked to prey abundance, Most breeding failures were predator related, and were more common in areas of relatively low nesting densities indicating lower parental vigilance there. High eagle breeding densities were associated with small mean territory sizes in the LSA (7.7 - 10.7km² for the main eagle species). Eagles in the LSA usually nested closer to another eagle species than a conspecific, resulting in regular distributions of nests and no territory overlap within species. Differences in daily flight activity of eagles in both study areas, and in the onset of breeding between LSA eagles probably reduced interspecific aggression. Interspecific competition food and nest sites amongst LSA eagles was possibly lessened by slight ditferences in resource selection. Raptor resources were mostly unaffected by human activities in either study area during the study period. Differences in the raptor communities were probably as a result of natural habitat differences. The CLSA raptors potentially face resource loss through forest clearing and hunting. An expansion of the present CAMPFIRE program will protect the CLSA raptors.

One of the most important emerging aspects of Third Generation Partnership Project (3GPP) is the Multimedia Broadcast/Multicast Service (MBMS) aiming to deliver multimedia contents to mobile users more efficiently in point-to-multipoint way. 3GPP also recommends an Application Layer Forward Error Correction (AL-FEC) scheme, especially for MBMS, in order to provide reliable transmission over mobile networks. Due to many emerging FEC schemes, the existing 3GPP standardized systematic fountain Raptor code FEC scheme is considered to be outdated. One of the newly emerged codes, namely RaptorQ, has enhanced an AL-FEC scheme by providing higher protection against packet loss and superior flexibility to meet the growing demand in mobile multicast services. In this work, we provide an extensive device based performance evaluation of RaptorQ FEC codes, specified as RFC 6330 in Internet Engineering Task Force (IETF), and notice that the performance always outperforms that of the existing Raptor (RFC 5053) codes in terms of decoding speed, latency and memory. We also include the device based performance comparison of RaptorQ FEC codes in a comparison with other FEC schemes like Supercharged codes and Reed Solomon + Low Density Parity Check codes (RS+ LDPC). Finally, we conduct simulation carried out in the mobile devices for several network parameters like latency, decoding speed and memory in combination with FEC encoding and decoding parameters and investigate that RaptorQ is the best code that suits multicast services.
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In this thesis, we investigate the optimization of Raptor codes for various channels of interest in practical wireless systems. First, we present an analytical asymptotic analy- sis of jointly decoded Raptor codes over a BIAWGN channel. Based on the analysis, we derive an optimization method for the design of efficient output degree distributions. We show that even though Raptor codes are not universal on other channels than the BEC, Raptor code optimized for a given channel capacity also perform well on a wide range of channel capacities when joint decoding is considered. Then, we propose a rate splitting strategy that is efficient for the design of finite length Raptor codes. We next investigate the extension of the analysis to the uncorrelated Rayleigh-fading chan- nel with perfect channel state information (CSI) at the receiver, and optimize Raptor codes for quasi-static fading channels when CSI is available at the receiver but not at the transmitter. Finally, we show that in presence of imperfect CSI at the receiver, it is possible to improve the performance with no additional complexity, by using an appropriate metric for the computation of the LLR at the output of the channel. In the second part of this thesis, we investigate the construction of efficient finite length LDPC codes. In particular, we present some improvements for the Progressive Edge- Growth algorithm that allow to construct minimal graphs. The proposed algorithm is used to construct protographs with large girth that perform well under iterative decoding. Moreover, we propose an efficient structured search procedure for the design of quasi-cyclic LDPC codes.

Le balbuzard pêcheur Pandion haliaetus est une espèce de rapace cosmopolite et migratrice mais menacée. C'est un modèle intéressant pour explorer comment les adaptations comportementales au sein de populations géographiquement distantes, ayant évoluées dans conditions écologiques différentes, pourraient être une cause proximale de leur distribution géographique et de différences génétiques et comportementales (stratégies migratrices et comportement de recherche alimentaire). Ainsi, j'ai mené une étude intégrative à différentes échelles afin de répondre à plusieurs questions fondamentales et appliquées.Grâce à une approche phylogéographique (phylogénie moléculaire) j'ai mis en évidence l'existence de quatre lignées différentes à l'échelle mondiale qui peuvent être considérées comme des Unités Evolutives Significatives (ESUs) et qui méritent des mesures de gestion spécifiques. En combinant des méthodes d'écologie moléculaire et d'observations d'oiseaux marqués, j'ai pu estimer le taux de connexion populationnelle dans le Paléarctique occidental. En combinant des outils d'écologie trophique en utilisant les isotopes stables, et d'écologie spatiale en utilisant de nouveaux outils en bio télémétrie, j'ai étudié les comportements migratoires et de l'écologie hivernale des balbuzards pêcheurs méditerranéens, que j'ai pu comparer avec ceux des populations nord européennes. Finalement, j'ai étudié la nécessité d'adopter des mesures de gestions adéquates pour trois population du bassin méditerranéen (Corse, Maroc, Italie), en comparant la dynamique des populations, en lien avec leurs ressources alimentaires (recensement des espèces piscicoles) et les perturbations d'origine anthropique. Dans l'ensemble, ce travail a conduit à des avancées significatives par rapport à la conservation des balbuzards pêcheurs à différentes échelles biogéographiques. Ces connaissances sont particulièrement utiles à l'égard d'une gestion efficace de cette espèce emblématique
Being a cosmopolitan and migratory species, the osprey Pandion haliaetus provides a good opportunity to explore how behavioural adaptations in different populations, that evolved under different ecological conditions and are widely spaced, can be the proximate causes of geographical distribution, genetic divergence, population connectivity, migratory strategies and foraging ecology. According to this, a multi-scale integrated approach has been adopted for the osprey: through an interdisciplinary framework made by molecular ecology, trophic ecology as assessed via stable isotopic analyses, spatial ecology through the use of novel biotelemetry tools, as well as population dynamics, fish censuses and assessments of levels of human disturbance, we: a) evidenced the existence of four different lineages at global scale that should be treated as Evolutionary Significant Units (ESUs) and deserve specific management; b) revealed population connectivity in the Western Palearctic; c) disentangled the migratory behaviour and winter ecology of Mediterranean ospreys and compared it with northern European populations, in an evolutionary context; d) stressed the need of adequate management measures to be adopted for three local populations of the Mediterranean basin (Corsica, Morocco and Italy). Overall, this work has led to some important advances with respect to the conservation biogeography of ospreys at different scales. Those insights are particularly valuable with respect to the effective management of this emblematic species

Being a cosmopolitan and migratory species, the osprey Pandion haliaetus provides a good opportunity to explore how behavioural adaptations in different populations, that evolved under different ecological conditions and are widely spaced, can be the proximate causes of geographical distribution, genetic divergence, population connectivity, migratory strategies and foraging ecology. According to this, a multi-scale integrated approach has been adopted for the osprey: through an interdisciplinary framework made by molecular ecology, trophic ecology as assessed via stable isotopic analyses, spatial ecology through the use of novel biotelemetry tools, as well as population dynamics, fish censuses and assessments of levels of human disturbance, we: a) evidenced the existence of four different lineages at global scale that should be treated as Evolutionary Significant Units (ESUs) and deserve specific management; b) revealed population connectivity in the Western Palearctic; c) disentangled the migratory behaviour and winter ecology of Mediterranean ospreys and compared it with northern European populations, in an evolutionary context; d) stressed the need of adequate management measures to be adopted for three local populations of the Mediterranean basin (Corsica, Morocco and Italy). Overall, this work has led to some important advances with respect to the conservation biogeography of ospreys at different scales. Those insights are particularly valuable with respect to the effective management of this emblematic species.

Die Optische Kohärenztomografie (OCT) ist eine neue Technik, die vor kurzem in der Humanophthalmologie etabliert wurde und sich durch ihr Potential auszeichnet, Retinastrukturen in vivo und nicht-invasiv (ohne Augenkontakt) in einer Qualität vergleichbar mit der von Histologieschnitten darzustellen. Diese Technik ermöglicht es, minimale pathologische Veränderungen bei fast histologischer Auflösung darzustellen, sowie longitudinale Untersuchungen im Verlauf der Erkrankung oder Therapie durchzuführen. In der Tiermedizin, vor allem in der Vogel-Ophthalmologie, wurde bis jetzt OCT nur sehr selten angewendet. Das Hauptziel dieser Studie war es daher, die Eignung der OCT-Technik als eine Darstellungsmethode in der Vogel-Ophthalmologie zu evaluieren. Um dieses Ziel zu erreichen, fokussierte diese Studie auf die Darstellung der physiologischen Retinastrukturen von Greifvögeln. Des Weiteren wurde die Anwendung von OCT bei vielen verschiedenen Greifvogelarten evaluiert, um erste Hinweise auf Unterschiede zwischen unterschiedlichen Arten und auf innerartliche Unterschiede der Retinastruktur zu gewinnen. Die Ergebnisse der OCT-Augenuntersuchungen wurden mittels histologischer Untersuchungen validiert. Um die Möglichkeiten der Darstellung der physiologischen Retinastrukturen von Greifvögeln mittels OCT zu überprüfen, wurden 56 wilde Tag- und Nachtgreifvögel drei verschiedener Familien und 12 verschiedener Arten untersucht. Alle einbezogenen Vögel waren Patienten der Klinik für Vögel, Reptilien, Amphibien und Zierfische der Ludwig-Maximilians-Universität München und wurden meist mit Verdacht auf Trauma vorgestellt. Die OCT-Untersuchungen wurden an Augen und Retinaregionen durchgeführt, welche nach einer vorherigen ophthalmologischen Untersuchung als gesund erachtet wurden. Bei Vögeln, die aufgrund ethischer und Tierschutzgründen euthanasiert werden mussten, wurden die Augen zur Validierung der OCT-Technik histologisch untersucht. Zur Darstellung der Retina wurde in der vorliegenden Untersuchung das Modell Spectralis® HRA+OCT Plus (Heidelberg Engineering, Heidelberg, Germany) verwendet. Die Bearbeitung der Fotos wurde mit der Spectralis Software Heidelberg Eye Explorer® (HEYEX) version 5.4 (October 2011, Heidelberg Engineering, Heidelberg, Germany) durchgeführt. Abhängig von der zu erwartenden Stresstoleranz des Patienten erfolgte die OCT Untersuchung im wachen Zustand oder es wurde vor Beginn der Untersuchung eine Sedation mit Midazolam (2 mg/kg KM) oder eine Inhalationsnarkose durchgeführt. Bei der Untersuchung des Fundus wurden fünf unterschiedliche Areale einbezogen, und zwar eine Region unmittelbar superior des Pecten oculi einschließlich eines Teils des Ansatzes des Sehnervenkopfes, die sagitalste Region des retinalen Äquators und des Fundus superior sowie die am weitesten temporal und nasal gelegenen Bereiche des Äquators. Dickemessungen der Retinaschichten in unterschiedlichen Retinaabschnitten wurden durchgeführt, um potentielle Dickeunterschiede darzustellen. Die Messungen beinhalteten erstens die gesamte Retina-Dicke (TRT) von dem retinalen Pigmentepithel bis zur Membrana limitans interna, zweitens die Nervenfaserschicht und Ganglienzellschicht (RNFL+GCL), drittens die äußere Retina (OR), mit den Schichten zwischen dem retinalen Pigmentepithel und der innersten Grenze der äußeren Körnerschicht, und viertens die Schichten zwischen dem retinalen Pigmentepithel und der äußeren Grenzmembran (RPE-ELM). Die histologischen Schnitte der Augen wurden nach einem Standardprotokoll mittels Davison’s Lösung als Fixation und Haematoxylin & Eosin Färbung angefertigt. Mittels OCT-Technik konnte die physiologische Struktur der Greifvogelretina mit einer Auflösung, die nicht von anderen tomographischen Techniken erreicht wird, reproduzierbar dargestellt werden. Die TRT und die RNFL+GCL war bei allen Spezies in der Region superior des Pectens maximal und verminderte sich zu den peripheren Regionen hin. Im Gegensatz dazu blieben die OR und die RPE-ELM von gleicher Dicke. Zwischen den einzelnen Spezies variierten die gemessenen Werte. Die gesamte Retinadicke (TRT) war bei Taggreifvögeln höher als bei Nachtgreifvögeln. Die Werte für OR und RPE-ELM hingegen waren bei Nachtgreifvögeln höer als bei Taggreifvögeln. Bei Pernis apivorus, Asio otus und Aegolius funereus konnte die äußere Körnerschicht nicht differenziert werden. Die OCT-Untersuchung der Greifvogel-Retina kann zusammenfassend als eine wertvolle Methode in der Vogelophthalmologie beurteilt werden. Diese Studie bietet die Grundlage für die Interpretation von OCT-Ergebnissen hinsichtlich pathologischer Veränderungen der Retina von Greifvögeln, sowie die Basis für eine in vivo Kontrolle von Krankheitsverläufen der Retina und die Beurteilung von Behandlungserfolgen über die Zeit.
Optical coherence tomography (OCT) is a new technique which has recently been established for routine human ophthalmology, focusing on its potential to visualize retinal structures in vivo and non-invasive, without eye contact, in a quality close to histological sections. This technique therefore permits to detect ocular disorders at almost (interpolated) histological resolution and, to be pointed out, longitudinal investigations on the course of disease or therapy. In veterinary medicine, especially in avian ophthalmology, until now, OCT has been applied only very scarcely. The main purpose of the present study was to evaluate OCT technique as an adequate imaging method at the avian retina. The study focused on the visualization of the physiological retinal architecture in raptors. Secondly, the application of OCT was evaluated in a broad range of raptor species in order to get first indications of interspecific variations in retinal structure revealed by OCT. Finally, the results of OCT eye examination were validated using histology. In order to test the potential of OCT to visualize the physiological retinal architecture in raptors, 56 diurnal and nocturnal wild raptors belonging to 3 orders and 12 species, underwent OCT examination. All these birds were patients of the Clinic for Birds, Reptiles, Amphibians and Ornamental Fish of the University Ludwig Maximilian (Munich) and were brought to the clinic mainly with a history of trauma. The OCT examination was performed on eyes and retinal regions considered healthy based on a previous ophthalmoscopical examination. The eyes of the patients euthanized due to humanitarian reasons were destined to histology in order to validate the technique. A Spectralis® HRA+OCT Plus (Heidelberg Engineering, Heidelberg, Germany) was used to image and evaluate the retina of the patients. The processing of the pictures was made with the software Spectralis Software Heidelberg Eye Explorer® (HEYEX) version 5.4 (October 2011, Heidelberg Engineering, Heidelberg, Germany). Depending on the expected stress tolerance, the OCT examination was performed with the patient awake, under sedation with Midazolam (2 mg/kg BW) or under general anaesthesia with isoflurane inhalation anaesthesia. The areas of the fundus considered were the superior portion of the Pecten oculi including a part of the optical nerve head (ONH), the most sagittal area of the retinal equator, the most sagittal area of the superiorly visualized fundus, the most temporal equatorial fundus area and the most nasal equatorial fundus area. Thickness measurements of retinal layers in the different retinal areas were performed in order to record potential thickness variations. Measurements included first, the total retinal thickness, from the retinal pigment epithelium up to the internal limiting membrane; second, the retinal nerve fiber layer and ganglion cell layer; third, the outer retina, which included the layers between the retinal pigment epithelium up to the innermost border of the outer nuclear layer; and fourth, the layers between the retinal pigment epithelium and the external limiting membrane. The histological processing of the eyes followed a conventional method to obtain histological sections of the retina in birds, using the Davison’s solution as fixation solution, and haematoxylin & eosin staining. The physiological architecture of the raptor retina imaged could be visualized with reproduceable results, and at a resolution not available to date. Regarding the intraspecific variations, the total retinal thickness (TRT) and the retinal nerve fiber layer and anglion cell layer (RNFL+GCL) were maximal at the region cranial to the pecten and decreased to the peripheral regions in all the species. On the contrary, the outer retina (OR) and the layers between the retinal pigment epithelium and external limiting membrane (RPE-ELM) maintained their size along the whole retina. Between species, the thickness of the different retinal measurements varied. The TRT was higher in diurnal species than in nocturnal species. By contrast, OR and RPE-ELM showed higher measurements in the nocturnal species than in the diurnal species. In the species Pernis apivorus, Asio otus, and Aegolius funereus, the outer nuclear layer (ONL) could not be distinguished. In summary, the optical coherence examination of the raptor retina may be considered as an invaluable tool in the avian ophthalmology. This study provides a basis to perform a more accurate interpretation of pathological findings observed with OCT in the retina of birds of prey.
La tomografía de coherencia óptica (OCT) es una técnica recientemente establecida en oftalmología humana de rutina, centrándose en la visualización de las estructuras de la retina en vivo, de forma no invasiva, sin contacto con el paciente y en una calidad cercana a la histología. Por ello esta técnica permite detectar desordenes oculares mínimos y de forma longitudinal, con lo que se puede seguir el curso de la enfermedad y la evolución de la terapia. En medicina veterinaria, especialmente en oftalmología aviar, esta técnica se ha aplicado de forma escasa. El objetivo principal del presente estudio fue evaluar la técnica de la OCT como método adecuado en oftalmología aviar. Para alcanzar este propósito el estudio se centró en la visualización de la arquitectura fisiológica de la retina en rapaces. Para ello se evaluó la aplicación de la OCT en un gran rango de especies de rapaces para obtener los primeros indicios de variaciones intraespecíficas en la estructura de la retina reveladas con la OCT. Para finalizar, los resultados se validarían utilizando histología. Como materiales y métodos para evaluar el potencial de la OCT se examinaron 56 aves rapaces, diurnas y nocturnas, de 3 órdenes y 12 especies. Los pacientes fueron en todos los casos de la Clínica de Aves, Reptiles, Anfibios y Peces Ornamentales de la Universidad Ludwig-Maximilian de Munich, prácticamente todos ellos a causa de un traumatismo. La OCT se llevó a cabo en los ojos y en las zonas de la retina consideradas sanas tras un previo examen oftalmoscópico. Los ojos de las aves que debieron eutanasiarse por razones de bienestar animal se destinaron a la validación de la técnica por medio de histología. El aparato utilizado para visualizar la retina de los pacientes fue el Spectralis® HRA+OCT Plus (Heidelberg Engineering, Heidelberg, Alemania) y el procesamiento de las imágenes a través del software Spectralis Software Heidelberg Eye Explorer® (HEYEX) versión 5.4 (Octubre 2011, Heidelberg Engineering, Heidelberg, Alemania). Dependiendo de la tolerancia demostrada por el paciente, la OCT se realizó con el paciente despierto, en sedación con midazolam (2 mg/Kg. MC) o bajo anestesia inhalatoria general. Las áreas del fondo de ojo consideradas en el estudio fueron la porción superior del Pecten oculi, incluyendo una parte de la cabeza del nervio óptico, las zonas más sagitales del ecuador y de la zona más superior visualizada y las zonas ecuatoriales más temporales y nasales visualizadas. En cada sección de cada área se llevaron a cabo medidas del grosor de las capas de la retina tales como el grosor de la retina total (TRT), la capa de fibras nerviosas de la retina junto con la capa de células ganglionares (RNFL+GCL), la retina externa (OR), y por último las capas comprendidas entre el epitelio pigmentario retiniano y la membrana limitante externa (RPE-ELM). Posteriormente los ojos a disposición de los pacientes eutanasiados se sometieron al procesado histológico utilizando como solución fijadora la solución de Davidson, y una tinción convencional de hematoxilina & eosina. La arquitectura fisiológica de la retina se visualizó de manera fiable con la técnica de la OCT, alcanzando resoluciones no posibles de alcanzar mediante otras técnicas topográficas. Entre las variaciones intraespecíficas observadas, se obtuvo como resultado que el TRT y el RNFL+GCL alcanzan valores máximos en el área craneal al pecten, y mínimos en las zonas de la retina excéntrica en todas las especies del estudio. Por el contrario, la OR y el RPE-ELM se mantuvieron constantes en grosor a lo largo de toda la retina. Se observaron grandes variaciones interespecíficas, entre los diferentes órdenes, y entre especies diurnas y nocturnas. El TRT es mayor en las especies diurnas que en las nocturnas. En cambio la OR y el RPE-ELM revelaron medidas más grandes en las especies nocturnas que en las diurnas. Una peculiaridad observada fue que en ciertas especies como Pernis apivorus, Asio otus, y Aegolius funereus, no se pudo observar la capa nuclear externa. Para finalizar, la tomografía ce coherencia óptica en cuanto al examen de la retina de las aves rapaces puede considerarse como una herramienta de incalculable valor en la oftalmología aviar. Este estudio proporciona la base para llevar a cabo una interpretación más exacta y adecuada de los hallazgos patológicos observados con la técnica de OCT en la retina de las aves rapaces.

Thesis (M.S. in Human Systems Integration)--Naval Postgraduate School, June 2009.
Thesis Advisor(s): Shattuck, Lawrence G. "June 2009." Description based on title screen as viewed on July 14, 2009. Author(s) subject terms: Cognitive Systems Engineering, Ecological Interface Design, Direct Perception, Direct Manipulation, Situation Awareness, Decision Making, Cognitive Workload, DMSC, C-SWAT. Includes bibliographical references (p. 171-174). Also available in print.

The seasonal migration of birds is one of the great phenomena of the natural world and satellite tracking provides a valuable means to analyse the behavioural and environmental factors that influence it. In this study satellite telemetry was used to track ospreys Pandion haliaetus during migration between the United Kingdom and West Africa. Autumn migrations were faster than those in spring, with more favourable meteorological conditions resulting in ospreys requiring fewer travelling days to reach their destination. They also incorporated time-minimisation techniques during southward journeys, indicating that selection-pressure influences migration speed in autumn as well as during spring migrations. The reclamation of winter territories is likely the key behavioural driver during autumn, particularly as later-departing individuals migrated faster. High resolution GSM-GPS transmitters provided new insights into the ability of ospreys to adapt flight method to environmental conditions, with tagged individuals exploiting thermal updrafts when available, but swapping to energy-demanding flapping flight when necessary. Very long ocean crossings, particularly across the Bay of Biscay, were regularly undertaken in autumn, when tailwinds aided progress. These flights were predominantly undertaken by flapping, but ospreys sometimes exploited weak thermals and elements of the wind to achieve soaring-gliding flight over the sea, the first time such behaviour has been documented. Individuals also regulated both flapping and gliding airspeed in response to changing wind conditions. Juvenile ospreys showed clear individual variation in the timing and speed of migration. Migration routes during the first migration were profoundly influenced by weather conditions, with wind drift resulting in very long flights across the ocean. It was also notable that ospreys with the longest post-fledging phase migrated fastest. Juveniles generally exhibited energy-minimisation techniques during migration, indicating that they were less time-constrained than adults. This may be particularly important given that individuals are likely to gain fitness advantages by arriving at the wintering grounds in good condition.

In order to understand the effects of climate change on the peregrine’s future prospects, we investigated the relationship between weather variables (extreme weather) and breeding success parameters for the peregrine in South Greenland. We defined two variables for comparison with weather data: young per known territory and nest success, i.e. proportion of known sites producing young, for each monitored year (N = 33). Weather data were obtained from two weather stations in the study area. From the weather data four extreme predictor variables were calculated: extreme low temperature, extreme precipitation, consecutive rainy days and total days with extreme weather. Peregrine breeding success (both parameters) was correlated negatively with number of days with extreme weather; the strongest correlation found was between total days in the season with extreme weather and breeding success. Low temperature and total days with extreme weather during the pre-laying and incubation period were also significantly negatively correlated with breeding success. Thereby, extreme weather is an important factor in explaining the peregrine’s breeding success. However, other factors also influence the breeding success, in the last few years there has been a strong downward trend but not an increase of extreme weather events during the same period.
Den globala uppvärmningen påverkar Arktis klimat vilket orsakar en snabbt föränderlig miljö för den Arktiska biotan. Effekten av klimatförändringarna är ökade väder variationer och extremer. Pilgrimsfalken är en väl studerad toppredator men få studier har undersökt hur extremt väder påverkar pilgrimsfalkens häckningsframgång i arktiska miljöer. Därför undersöker vi förhållandet mellan extrema väder och häckningsframgången för pilgrimsfalken på södra Grönland. Vi har i denna studie använt data om pilgrimsfalkens häckningsframgång på södra Grönland som sträcker sig från år 1981 och fram till 2015. Väderdata som använts för att kalkylera variablerna: extrem temperatur, extremt regn, regndagar i följd och totalt antal dagar med extremt väder har erhållits från två väderstationer inom studieområdet. Häckningssäsongen analyserades i sin helhet samt delades in i perioderna: “innan äggläggnings-”, “ruvnings-” och “ungar-i-boet-perioden”, vilka korrelerades mot vädervariablerna. Vi fann att dagar med extremt väder påverkar pilgrimsfalkens häckningsframgång negativt under hela säsongen samt under perioderna “innan äggläggning” och “ruvning”. Extrema väderhändelser kan alltså förklara variationer i häckningsframgången för pilgrimsfalken på södra Grönland. Resultatet indikerar även att andra faktorer påverkar häckningsframgången då det finns en stark nedåtgående trend i pilgrimsfalkens häckningsframgång men inte en ökning av extrema väderhändelser under samma period.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
Understanding the horsepower demands that electrical and hydraulic systems place on an aircraft engine is critical since this directly effects engine performance. The current methods of measuring horsepower have been mainly limited to lower rpm engines and are not suitable for higher rpm jet engines. L-3 Telemetry East has developed instrumentation for the F-22 instrumentation group that is capable of measuring horsepower loads on engine shafts that are rotating at up to 18000RPM. This paper describes the operation of this system.

Populations of birds of prey, henceforth raptors, have declined worldwide, mostly from anthropogenic causes. Because their role as apex predators in ecosystems is considered vital for ecosystem health, conservation efforts have been implemented throughout their distribution. In many cases, we do not know enough about their basic food and habitat requirements, which is requisite if we are going to be able to protect them. The purpose of this study was to describe the habits and biology of nesting martial eagles by looking at the chick’s diets and the roles of male and female eagles in provision and presentation (dismemberment) of prey to the chicks. Data were collected non-obtrusively by fitting five nests in the Maasai Mara and one in the Rift Valley region of Kenya with cameras that were both motion-triggered and programmed to take images every five minutes. Based on analysis of 214,000 image frames, the diet of nesting martial eagles and their chicks was found to be comprised of 23 different species within four broad prey categories (gamebirds, domestic poultry, large ungulates and small ungulates), of which gamebirds were the most important. There were sex-based differences in parental feeding, with females selecting for larger and heavier prey items than males. Males were the primary foragers for the chicks up until the eighth to eleventh week of chick development, after which the females became more involved. In addition, before delivery to the nest, large prey were more often dismembered than small and medium-sized prey. This study is the first in Africa to use nest-cams to study martial eagles over the breeding season, corroborating previous studies that have shown sex-dependent differences in chick nurturing. My results contribute to establishing a fuller picture that can be used in future conservation actions and management decisions that can be used to protect this species and their prey base.
Beståndet på rovfåglar (hädanefter raptor) har minskat över hela världen, mestadels på grund av all antropomorfisk verksamhet. Eftersom deras roll som topprovdjur i ekosystem anses vara oerhört viktig för ekosystemens hälsa har bevarandeinsatser genomförts i alla deras habitat. I många fall vet vi inte tillräckligt om deras grundläggande mat- och livsmiljökrav, vilket är nödvändigt om vi skall kunna skydda dem. Syftet med denna studie var att beskriva habitat och biologi hos häckande stridsörnar genom att titta på ungarnas dieter och rollen som hanor och honor i tillhandahållande och presentation (rivning) av byte till ungarna. Data samlades in genom att använda en icke-störande teknik. Kameror som var både rörelsestyrda och programmerade att ta bilder var femte minut monterades vid fem bon i Maasai Mara och en i Rift Valley-regionen i Kenya. Baserat på analys av 214 000 bildramar konstaterades att dieten för häckande stridsörnar och deras ungar bestod av 23 olika arter inom fyra breda byteskategorier (viltfåglar, tamfåglar, stora hovdjur och små hovdjur), varav viltfåglar var de viktigaste. Det fanns könsbaserade skillnader i kost som ungarna fick, med honor som valde större och tyngre byte än hanar valde. Hanar var de främsta furagerare fram till den åttonde veckan av ungarnas utveckling, då blir honor mer involverade. Dessutom blev stort byte ofta delade ned innan leverans till boet än små och medelstora byten. Denna studie är den första i Afrika som använde kamror för stridsörnar under Häckningssäsong och den bekräftar tidigare studier som har visat könsberoende skillnader i skötsel av ungar. Mina resultat bidrar till att skapa en mer fullständig bild som kan användas i framtida bevarandeåtgärder och förvaltningsbeslut som kan användas för att skydda denna art.

Due to Covid-19 all presentations and defences were held online

mTOR is the central kinase in biochemical pathways that regulate cellular growth, protein synthesis and cell survival. Deregulation of mTOR signaling results in uncontrolled cell proliferation and hence is implicated in various cancers and autoimmune diseases. mTOR functions through two distinct signaling complexes, called mTORC1 and mTORC2. CCT is a cytosolic chaperonin that assists in folding of several protein substrates. In these studies, we have identified two components of the mTOR complexes, mLST8 and Raptor, as substrates of CCT. We have performed biochemical and signaling studies which indicate that CCT is involved in assembly and signaling of mTOR complexes by folding β-propeller domains of mLST8 and Raptor. We have also obtained high resolution structural information of the mLST8-CCT complex by cryo-EM and mass spectrometric cross-linking. Moreover, we have explored the role of PhLP1 as a co-chaperone for CCT in the assembly of mTOR complexes. Interestingly, we found that PhLP1 plays very different roles in the case of mLST8 and Raptor. While PhLP1 participate in assembly of mLST8 into mTOR complexes, it facilitates degradation of Raptor. These biochemical data, combined with structural information, can be used to design small molecules that modulate mTOR signaling by affecting the formation of intact mTOR complexes.

Birds of prey are difficult to study and the status and distribution of many species is poorly known. As top predators usually occurring at low densities, raptors may be particularly sensitive to habitat degradation. Conservation of raptors might be vital to prevent further loss of species and ecosystems. Between April and December in 2008 and 2009, raptors and associated habitat data were surveyed using a distance sampling transect method in 70 randomly selected one square kilometre plots in the Cerros de Amotape National Park, the Tumbes National Reserve and buffer areas within the North West Biosphere Reserve in Peru. A total of 1261 detections of 19 diurnal raptor species were recorded. I examined community structure, diversity across land uses and relationships between abundance and niche attributes within species. Abundance and richness were highest outside protected areas and lowest in the national park. A Canonical Correspondence Analysis (CCA) of raptor species and habitat variables ordinated them according to latitude, elevation, percentages of vegetation cover, and, in some cases, individual tree species. I used logistic regressions (GLMs) to obtain habitat distribution models for eleven raptor species. Twenty eight habitat models were obtained and twelve habitat variables were included. Best models included measured percentage of vegetation cover at different strata, elevation and latitude. My findings suggest that vertical structure of forested areas is of particular importance for raptors in extreme northwest Peru. iii Density and population size estimates were calculated for 15 species using distance sampling line transect counts. Densities were stratified by time of detection (morning or afternoon) and by habitat type. Flying birds were included in the analysis. For all but two species, density estimates were higher in the morning than in the afternoon. Absolute density was higher than 1 individual km-2 for three species and for seven species it lay between 0.34 and 0.86 individuals km-2. Some species showed a marked preference for particular habitat types. I used generalized additive models (GAMs) to examine the relationship between the occurrence of six diurnal raptors and species diversity and abundance to vegetation structure, elevation and cattle „density‟ in 39 km² plots within my study area. Percentage of vegetation cover 5-15 m above the ground was the most important feature influencing the distribution of most species, including the rarer ones. Raptors responded differently to cattle density: Presence of species that foraged in open habitats increased with cattle density, while presence of range restricted or declining species decreased. Conservation efforts of raptors in extreme northwest Peru should also be conducted in areas outside the North West Biosphere Reserve by protecting remaining forests. Moderate cattle densities can benefit some species and help maintain a high raptor diversity in the study area. However, this activity should be strictly monitored so further fragmentation of forests and damage to vegetation structure is significantly reduced particularly inside the Tumbes National Reserve.

Includes abstract.
Includes bibliographical references.
Range shifts and expansions have been recorded in a number of species and it is expected that as climate change proceeds it will result in more species joining this trend. A major concern with these shifts is the suitability of the receiving novel environments, for example, if these areas experience different climatic conditions or prey phenology. One way to evaluate how expanding populations adapt to the environment is through evaluating their breeding patterns. In southern Africa, the Black sparrowhawk (Accipiter melanoleucus) originally existed in Botswana, Mozambique, North Eastern and South Eastern South Africa and Zimbabwe.

Includes abstract.
Includes bibliographical references.
Range shifts and expansions have been recorded in a number of species and it is expected that as climate change proceeds it will result in more species joining this trend. A major concern with these shifts is the suitability of the receiving novel environments, for example, if these areas experience different climatic conditions or prey phenology. One way to evaluate how expanding populations adapt to the environment is through evaluating their breeding patterns. In southern Africa, the Black sparrowhawk (Accipiter melanoleucus) originally existed in Botswana, Mozambique, North Eastern and South Eastern South Africa and Zimbabwe.

Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xviii, 192 p.; also includes graphics. Includes bibliographical references (p. 156-192).

Two rates of Raptor herbicide were evaluated for late winter weed control in alfalfa in combination with various types of surfactancts, the insecticide Furadan, and other alfalfa herbicides with known limited control spectrums. Herbicides that were combined with Raptor were also evaluated separately, as was Pursuit. Effects of treatments on wild oats, littleseed canarygrass and annual sowthistle were obtained. Treatments containing the active ingredient clethodim (Select/Prism) reduced canarygrass height and reproduction, while Raptor treatments increased numbers of inflorescences. No treatment provided effective control of sowthistle although some activity was noted from the Raptor treatments when numbers of reproductive structures and height were examined. Surfactants/ adjuvants greatly increased Raptor activity. Wild oat control was noted in treatments containing clethodim and several Raptor treatments when utilizing a surfactant/adjuvant.

Early concept generation is the base for the final products appearance. Since most of the products character and cost is set at an early stage increased knowledge at an early stage is vital. This master thesis aims at creating a method called RAPTOR. The purpose of RAPTOR is to reduce the cost and increase the knowledge by combining CAD and optimization with an easy excel interface.

For illustrative purpose an electric motor example has been used. The master thesis has been demonstrated at GM power train, Trollhättan Sweden, and a considerable interest was shown.

The inspiration comes from the GlobaLiTH project, a project at the machine design department at Linköping University, Sweden, where a sustainable light utility vehicle was designed.

Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 9, 2007) Vita. Includes bibliographical references.

The demand for multimedia applications is increasing and existing point-to-point data communication systems cannot meet the requirements for high data rate multimedia transmission. This leads to the introduction of more spectrally efficient point-to-multipoint services. However, efficiently transmitting large data to a heterogeneous and large receiver population over unreliable wireless channels requires sophisticated multi cast techniques. The aim of this thesis is to design and quantify the benefits of application layer solutions that provide end-to-end reliability for multicast WLAN transmission. To this end, a cross-layer design based on the latest RaptorQ (RQ) codes for transmitting high data rate video over the multiple input multiple output (MIMO) channels in realistic outdoor environments is presented. RQ code performance is investigated for spatial multiplexing (SM) systems. A detailed crosslayer simulator is used to define the optimum system parameters under different MIMO channel conditions. The channels are generated using a state-of-the-art 3D ray tracing tool and are used to evaluate performance in realistic outdoor environments. It is shown that with the use of Raptor codes there can be up to 10 dB improvement in the required signal to noise ratio (SNR) depending on the correlation between the MIMO channels. An adaptive MIMO technique is proposed that considers Raptor code application layer forward error correction (AL-FEC) in SM as a means to enhance reliability and transmission efficiency. The benefits of the proposed system are highlighted using a site specific case study. This thesis proposes a FEC carousel model based on Raptor codes for wireless multicast transmission over WLANs. Different carousel models, namely sequential and interleaved models, are designed and evaluated in realistic environments. It is shown that the interleaved carousel model provides a lower download time and superior coverage as compared to the sequential model. A complete system design methodology that enables the trade-off between user coverage, AP density and data download time to be managed in a complex real-world environment is presented. Furthermore, the proposed multicast carousel system is validated via experimental measurements. This thesis presents the first detailed analysis on the implementation ofRQ codes and data carousels in a practical Wi-Fi based server/client system. It is shown that system performance is mostly dominated by hardware and software limitations on constrained host platforms where the incoming packet rate exceeds the device's ability to consume the traffic. RQ parameters are evaluated through measurements. It is recommended to choose Raptor source block length K ::; 200 and symbol size T;::: 1000 bytes in order to provide a better quality of experience. Finaliy, an adaptive FEC carousel system, which provides reliable and scalable multicast transmissions over the IEEE 802.11 WLANs, based on Raptor codes is proposed. It is shown that the adaptive system significantly reduces the average download time, increases the percentage of satisfied users and effectively utilises the valuable radio and network resources in a multicast network with suitable design parameters.

Thesis (M.S.)--West Virginia University, 2003.
Title from document title page. Document formatted into pages; contains xii, 106 p. : col. ill., col. maps. Includes abstract. Includes bibliographical references.

Gray hawks became established in the San Pedro River (SPR) valley in the mid-1900s following landscape changes that created habitat for them. The population of gray hawks along the SPR is at the northern edge of the species’ range, and its growth has been documented periodically since the 1970s. A study in the 1990s quantified gray hawk diet and habitat use in this area, and found that gray hawks hunt primarily in mesquite, eat mostly lizards, and that their productivity is positively correlated with the percentage of mesquite in their territories. The gray hawk population along the SPR has nearly doubled since the initial study was conducted, and pairs now nest in areas that contain little or no mesquite. Our main objectives were to determine whether: a) diet and habitat requirements have changed for gray hawks along the SPR since the population has as expanded, and b) productivity has declined as the population has expanded into habitats of potentially lower quality. We used nest cameras to document prey deliveries, and ESRI ArcGIS to quantify vegetation types within estimated home ranges of gray hawks. We compared productivity of gray hawk pairs in the 1990s and the 2010s, as well as the current productivity of pairs in territories that had been occupied by gray hawks in the 1990s (original territories) and those that only became occupied after the original study was completed (new territories). We found that that gray hawks used a wider variety of vegetation types, such as nest trees surrounded by grasslands, and consumed a wider variety of prey than they did in the 1990s, and that productivity remained constant over time. Like many populations at the edge of their range, the gray hawks that initially settled in the San Pedro River valley likely had access to only a portion of the resources that are common at the center of the species’ range, and therefore appeared to have a narrower set of diet and habitat requirements than the species as a whole. Areas that are currently being used by gray hawks for nesting (e.g., nest trees surrounded by grasslands) were likely unsuitable in the 1990’s because they were being used for agriculture and grazing. The two chapters of this thesis will be submitted to journals for publication and therefore contain overlapping information.

Decreasing enrollments, lower rates of student retention and changes in the learning styles of today's students are all issues that the Computer Science (CS) academic community is currently facing. As a result, CS educators are being challenged to find the right blend of technology and pedagogy for their curriculum in order to help students persist through the major and produce strong graduates. Visual technologies are being explored as a way to present difficult programming concepts in a manner that is easier to visualize and simpler to use. Visual technologies can make learning programming easier by minimizing the syntax of the programming language being used and providing visual feedback to the students to aid in conceptualization of the programming constructs. The goal was to improve student retention and performance by incorporating visual technologies in the introductory programming course, CS1, at East Tennessee State University (ETSU). The ADDIE approach to instructional design was used to develop and implement a curriculum that incorporated visual technologies in CS1 at ETSU. Subsequently, quasi-experimental research methods, using the Post-Test Only Nonequivalent Groups Design approach, were used to perform assessment on the effects of the revised curriculum on student performance in the course and retention in the major as compared to student performance and retention as measured prior to the course redesign. The results of the study indicate a positive impact on student performance in CS1 and student retention in the major as a result of the use of two types of visual technologies in CS1 at ETSU. Visual technologies supporting algorithm development, such as RAPTOR, had a positive impact on student performance in the area of problem solving and algorithm development as well as the use of decision and repetition constructs in programming. Visual technologies supporting program development, such as Alice, had a positive impact on student performance in the area of object-oriented programming concepts such as objects and classes. The combination of these two types of visual technologies showed evidence of improvement among student performance as a whole in the course and slight improvement in student persistence in the major.

Mobile communication systems are undergoing revolutionary developments as a result of the rapidly growing demands for high data rates and reliable communication connections. The key features of the next-generation mobile communication systems are provision of high-speed and robust communication links. However, wireless communications still need to address the same challenge–unreliable communication connections, arising from a number of causes including noise, interference, and distortion because of hardware imperfections or physical limitations. Forwarding error correction (FEC) codes are used to protect source information by adding redundancy. With FEC codes, errors among the transmitted message can be corrected by the receiver. Recent work has shown that, by applying rateless codes (a class of FEC codes), wireless transmission efficiency and reliability can be dramatically improved. Unlike traditional codes, rateless codes can adapt to different channel conditions. Rateless codes have been widely used in many multimedia broadcast/multicast applications. Among the known rate- less codes, two types of codes stand out: Luby transform (LT) codes and Raptor codes. However, our understanding of LT codes and Raptor codes is still in- complete due to the lack of complete theoretical analysis on the decoding error performance of these codes. Particularly, this thesis focuses on the decoding error performance of these codes under maximum-likelihood (ML) decoding, which provides a benchmark on the optimum system performance for gauging other decoding schemes. In this thesis, we discuss the effectiveness of rateless codes in terms of the success probability of decoding. It is defined as the probability that all source symbols can be successfully decoded with a given number of success- fully received coded symbols under ML decoding. This thesis provides a detailed mathematical analysis on the rank profile of general LT codes to evaluate the decoding success probability of LT codes under ML decoding. Furthermore, by analyzing the rank of the product of two random coefficient matrices, this thesis derived bounds on the decoding success probability of Raptor codes with a systematic low-density generator matrix (LDGM) code as the pre-code under ML decoding. Additionally, by resorting to stochastic geometry analysis, we develop a rateless codes based broadcast scheme. This scheme allows a base station (BS) to broadcast a given number of symbols to a large number of users, without user acknowledgment, while being able to pro- vide a performance guarantee on the probability of successful delivery. Further, the BS has limited statistical information about the environment including the spatial distribution of users (instead of their exact locations and number) and the wireless propagation model. Based on the analysis of finite length LT codes and Raptor codes, an upper and a lower bound on the number of transmissions required to meet the performance requirement are obtained. The technique and analysis developed in this thesis are useful for designing efficient and reliable wireless broadcast strategies. It is of interest to implement rateless codes into modern communication systems.

Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xii, 73 p. : ill. (some col.), map (some col.). Vita. Includes abstract. Includes bibliographical references.

The heterogeneity of breeding environment leads the evolution of different behavioural strategies that individuals undertake to guarantee their fitness and survival. Moreover, the cyclic nature of animal life determines that each set of decision made by individuals during reproduction could severely affect behaviour and fitness traits during their successive stages of life cycle. Among different species that have been studied to investigate these relationships, migratory birds are optimal model species, since the rigid scheduling of their life cycle exacerbates the associations established among breeding environmental variations, fitness and behaviour. In the present thesis, I investigated the possible effects of variation in the breeding environment on fitness and behavioural traits of a colonial, migratory, avian species the lesser kestrel (Falco naumanni), assessing possible effects during two different temporal scales: in the current breeding season (short-term effects) and/or during successive life stages (long-term effects). In the first part, I analysed short-term effects of breeding environmental variations, observing whether nest-site quality and food resource abundancy and distribution could affect fitness and behaviour of lesser kestrel. Firstly, I have investigated the strategy implemented by lesser kestrel during nest-site selection, and whether individual differences in the nest-site preference could affect fitness. Secondly, I have assessed whether food resource abundancy could limit lesser kestrel’s breeding performance and whether the patchy prey distribution in the breeding environment could negatively affect their foraging behaviour and fitness. In the second part, I have investigated whether variation in breeding environment could affect lesser kestrel during successive stages of the life cycle. I therefore analysed whether breeding area continental distribution affects migratory behaviour and strategy of five European populations of lesser kestrel. The overall results reported in this thesis suggested that lesser kestrel suffers variations in the breeding environment that occur during the current breeding season, indeed I have assessed that individuals rely on public information gathered from the environment to choose the most suitable nest-site and to identify optimal foraging areas. Foraging strategies adopted by lesser kestrel during the breeding season have evolved to cope with the heterogeneous prey distribution and to limit intraspecific competition among individuals of the same and different colonies. Moreover, food resource abundancy mediates individual fitness according to parent body condition. Finally, despite the absence of any direct effects of lesser kestrel migratory connectivity on individual fitness, I observed that the continental distribution of the breeding site reflects the location of the non-breeding areas in Africa. This evidence highlighted that European populations remain separated during the African stay and thus are subjected to different abiotic and biotic traits with possible profound effects on population dynamics.

FSO is an optical wireless line-of-sight communication system able to offer good broadband performance, electromagnetic interference immunity, high security, license-free operation, low power consumption, ease of relocation, and straightforward installation. It represents a modern technology, significantly functional when it is impossible, expensive or complex to use physical connections or radio links. Unfortunately, since the transmission medium in a terrestrial FSO link is the air, these communications are strongly dependent on various atmospheric phenomena (e.g., rain, snow, optical turbulence and, especially, fog) that can cause losses and fading. Therefore, in worst-case conditions, it could be necessary to increase the optical transmission power, although, at the same time, it is needed to comply to safety regulations. The effects of the already mentioned impairments are: scattering (i.e., Rayleigh and Mie) losses, absorption and scintillation. The first two can be described by proper attenuation coefficients and increase if the atmospheric conditions get worst. As regards scintillation, it is a random phenomenon, appreciable even under clear sky. Because of scintillation, in FSO links, the irradiance fluctuates and could drop below a threshold under which the receiver is not able to detect the useful signal. In this case, communications suffer from erasure errors, which cause link outages. This phenomenon becomes relevant at high distance, but it can also be observed in 500m-long FSO links. Moreover, the optical turbulence intensity can change of an order of magnitude during the day: it reaches its maximum around midday (when the temperature is the highest) and, conversely, it is lower during the night. In order to reduce or eliminate these impairments, different methods (both hardware and software) were studied and reported in literature. Hardware solutions focus on aperture averaging effects to reduce irradiance fluctuations, in particular by using a bigger detector or multi-detector systems. On the other hand, software techniques mostly focus on transmission codes. Rateless codes are an innovative solution, suitable for channels affected by erasure or burst errors. They add a redundant coding (also settable on the fly) to the source data, allowing the receiver to successfully recover the whole payload that, otherwise, would be corrupted or partially lost. To test rateless codes, recovery capabilities in FSO channels, detailed information about the occurring signal fading are needed: in particular, its depth, temporal duration and statistics. For this reason, I have implemented a time-correlated channel model able to generate an irradiance time-series at the receiver side, at wide range of turbulence conditions (from weak to strong). The time-series represents a prediction of temporal irradiance fluctuations caused by scintillation. In this way, I was able to test the recovery capabilities of several types of rateless codes. I have performed measurement campaigns in order to characterize Free Space Optics links affected by the optical turbulence. In particular, I have used three different setups placed in the Laboratory of Optics of the University of Palermo and in the Optical Communication Laboratory of the Northumbria University. Thanks to an in-depth post-processing of the collected data, I was able to extract useful information about the FSO link quality and the turbulence strength, thus proving the effectiveness of the Gamma-Gamma model under several turbulence conditions. In Chapter 1, I will introduce the theory of optical wireless communications and, in particular, of Free Space Optics communications. In detail, I will describe the advantages and the impairments that characterize this kind of communication and discuss about its applications. In Chapter 2, the adopted channel models are presented. In particular, these models are able to predict irradiance fluctuations at the detector in Free Space Optics links and were designed for terrestrial and space-to-ground communications at different link specifications, turbulence conditions and temporal covariance. Firstly, a brief description of the employed irradiance distribution and of the irradiance covariance functions is presented. The details of the above mentioned channel model implementation and the performance are then described. Finally, in order to detail the channel model features, several examples of irradiance fluctuation predictions are depicted. In Chapter 3, the details of a measurement campaign, focused on the analysis of optical turbulence effects in a FSO link, will be treated. Three different measurement setups composed of different typologies of laser sources, detectors and turbulent channels will be described. Data post-processing will be discussed. Moreover, a performance evaluation of the terrestrial channel model described in Chapter 2 will be discussed. In Chapter 4, rateless codes will be presented. These codes introduce a redundancy by means of repair symbols, associated to the source data, and, in case of losses, they are able to recover the source data without any need for retransmission. They can also manage large amounts of data and offer very interesting features for erasure channels and multicast/broadcast applications. Three different classes of rateless codes will be described and, in particular: Luby Transform, Raptor and RaptorQ codes. Moreover, the performance of the rateless codes in Free Space Optics links will be investigated. The implemented simulators are based on the channel models presented in Chapter 2 and focus on the study of rateless codes recovery capabilities when erasure errors due to fadings occur. The results on the performance of three rateless codes typologies, in two different FSO links, will be illustrated. All the research work was supported by the European Space Agency (grant no. 5401001020). Experimental activities were performed in collaboration with the Optical Communications Research Group of the Northumbria University and within the COST IC1101 European Action.

Este trabajo busca analizar el uso de los elementos emocionales del storytelling asociados al atributo del producto para reforzar la identidad de marca de Ford. Sabemos que, en el Perú, la oferta en automóviles es muy grande, por lo que cada marca intenta comunicar diferentes cosas sobre sus productos, desde aspectos tangibles de un automóvil, hasta tratar de darle una personalidad a cada uno. También sabemos que la elección de un producto como este es muy complicada, por lo que las marcas deben optar por comunicar de cierta forma que atraiga al consumidor y logre reforzar su imagen de marca. Es por eso que el storytelling se convierte en la mejor opción. Para este trabajo queremos saber si realmente la asociación entre el storytelling y los atributos del producto refuerzan la imagen de marca. Es por esto que, en primer lugar, analizaremos los conceptos de cada uno de los términos a estudiar. Comenzaremos con atributo del producto y seguiremos con storytelling, branded content e imagen de marca. De la misma forma, analizaremos el porqué de la elección de la marca y el modelo Ford Raptor en la investigación. Por último, a través de un trabajo de campo, estudiando a los miembros de nuestro público objetivo y profesionales relacionados al caso y a la marca, llegaremos a descubrir si la asociación del storytelling y de los atributos del producto refuerzan la imagen de la marca Ford.
This work seeks to analyze the use of the emotional elements of storytelling associated with the product attribute to reinforce Ford's brand identity. We know that, in Peru, the offer in cars is very large, so each brand tries to communicate different things about its products, from tangible aspects of a car, to trying to give each one a personality. We also know that choosing a product like this is no longer very complicated, so brands must choose to communicate in a way that attracts the consumer and manages to reinforce their brand image. That is why storytelling becomes the best option. For this work we want to know if the association between storytelling and product attributes really reinforces the brand image, in this case of Ford. This is why, in the first place, we will analyze the concepts of each of the terms to be studied. We will start with the product attribute and continue with storytelling, branded content and brand image. In the same way, we will analyze the reason for the choice of the Ford Raptor make and model in the investigation. Finally, through fieldwork, studying the members of our target audience and professionals related to the case and the brand, we will discover if the association of storytelling and product attributes reinforces the image of the Ford brand.
Trabajo de investigación

The thesis describes several methods of plasma state monitoring for feedback control. For a tokamak device operation, one needs to gain in real time some information about the plasma state. The amount of needed information increases with the size of the device. In small machines, such as ISTTOK and Golem, the plasma current centroid position control is sufficient, as the heat fluxes are low and the plasma is in limiter regime. In larger devices, like RFX-mod, TCV or ASDEX-Upgrade with more complex plasma shapes and higher heat fluxes on the first wall, it is necessary to measure and control the plasma shape and the heat flux deposition location on the first wall (strike points in diverted regime and plasma-wall contact point in limited regime). The plasma performance is also strongly affected by internal current and pressure profile shape. Additionally, the bootstrap current fraction, that can not be directly measured, plays significant role in more advanced tokamak operation regimes. These quantities related to internal profiles have to be well diagnosed in order to avoid disruptions and mitigate the MHD instabilities. The thesis deals with all the above mentioned layers of control complexity, starting from the simplest ones focused on plasma current centroid position measurement on ISTTOK, over more complicated real time shape and equilibrium monitoring to the most advanced tools useful for plasma internal profiles monitoring, control, instabilities mitigation and disruption avoidance. The work described in this thesis provides original contribution to each category of these methods. The first part of the thesis deals with real time applicable plasma current centroid position measurement on ISTTOK. In the frame of this work, two major issues had to be solved. The first, which is common for most small devices with highly conductive shell, is related to the impact of the eddy currents induced in the conductive structures that corrupt the magnetic diagnostic signal and consequently disable the plasma current centroid position measurement. This was solved by a simple, real time applicable state space model that takes into account both the vacuum vessel and the shell and is capable to clean all 12 magnetic sensors installed on ISTTOK from the eddy currents effect. The method has also been tested on RFX-mod and on data from tokamak Golem located in Prague, Czech Republic. The second problem is that the present magnetic diagnostics on ISTTOK is not well calibrated. Therefore a simple method less sensitive to calibration errors was used and validated against Heavy Ion Beam vertical position estimate. The resulting algorithm is reliable enough and capable of providing information about the plasma current centroid position both for real time plasma control and offline post-discharge analysis. In addition, a more advanced method of the plasma current centroid position measurement was proposed to be used after the magnetic diagnostic upgrade planned in near future. The next part of the work is dedicated to the tools for plasma shape and global macroscopic parameters measurement. It was performed on RFX-mod, a medium sized reversed field pinch operated also in tokamak regime. It is important especially because it started a diverted discharges program last years with the aim of performing MHD active control experiments in H-mode plasma. This part of the research activity focuses on the development of an algorithm for reliable plasma boundary reconstruction, both real time and offline that is applicable on RFX-mod. A real time plasma boundary reconstruction algorithm based on magnetic flux extrapolation in the vacuum suited to RFX-mod was developed and validated against Grad-Shafranov solver MAXFEA. This algorithm provides very good results (error below 2 % of the plasma minor radius) even in the presence of the limited poloidal number of sensors (8 pick-up coils and 8 poloidal flux loops) in RFX-mod with respect to standard tokamaks. As the algorithm does not provide just the knowledge of the plasma boundary, but it is also capable to compute the magnetic field and flux everywhere in the vacuum, it can be used to calculate several equilibrium related parameters such as βp + li/2, q95 in post-discharge analysis. For elongated discharges, the βp and li can be also separated. The value of βp provided by this algorithm is almost identical with an independent diamagnetic measurement. It was also used to provide feedback signals to the plasma shape control system designed for RFX-mod diverted discharges. Some shape control operation results are also reported in the thesis. The initial work on the real time plasma shape measurement and control opened the way to LH transition experiments. These experiments have shown H-mode evidence neither in steady state nor in transition phases of the ohmic discharges (mainly current ramp-up and ramp-down). However, the possibility of achieving H-mode in ohmic discharges is not excluded in future campaigns, since the feedback control on plasma density has been significantly improved. As a second attempt, a biasing electrode to induce LH transition was built and another campaign was carried out. These experiments were successful, since several clear signs of LH transition were observed: the steep drop of H alpha signal, increase of plasma density and pedestal formation at the edge. The description of these experiments is given within the thesis. The last part of the thesis was dedicated to a tool that is being developed to improve present methods of control of plasma current, temperature, pressure profile, and disruption avoidance, RApid Plasma Transport simulatOR (RAPTOR). This code complements a simple set of real time diagnostics and computes the missing information using a lightweight set of transport equations. The thesis contains description of the code, especially the physical simplifications made to cope the computational speed requirements of a real time code, and reports possible applications in the field of disruption prediction and avoidance. Dedicated experiments to test the prediction method have been performed on RFX-mod for Resistive Wall Mode disruptions in discharges with q(a)< 2 and on TCV for density limit disruptions. In both disruption classes, the sawteeth behavior is significantly modified before the disruption, but the modification is not reflected in the RAPTOR prediction. Therefore the sawteeth period has been used as a feedback variable: huge discrepancy between RAPTOR and experimental sawteeth period activates the disruption alarm. The experiments showed that RAPTOR in its present state of development is a valid tool for disruption prediction in ohmic L-mode plasma without significant shape changes: in RFX-mod, the disruption alarm was activated several tens of milliseconds before the disruption and in TCV hundreds of milliseconds before. The main benefit is that this method is physics based, hence it does not require huge discharge database to train neural networks as the present algorithms. It is also transferable from one device to another, which is not the case of present days disruption prediction tools. However, the future disruption avoidance tools must be capable to deal with much more complex plasmas than the studied L-mode ohmic cases. The last section of this thesis gives examples of disruption prediction on ASDEX-Upgrade and identifies the gaps that must be filled before RAPTOR becomes a full-blown disruption prediction tool. First of all, inclusion of all heating and current drive sources will be needed. Second important issue is the inclusion of a model of a fast ion pressure, that significantly contributes to the total plasma energy content and affects MHD modes dynamics, for example stabilizes sawteeth. Another important piece of the puzzle is the coupling of a real time Grad-Shafranov solver with RAPTOR, that can improve the equilibrium reconstruction quality, which is closely related for example to the control of the NTM instabilities. Last, not least, huge benefit can be obtained from a better real time estimate of the electron temperature profile by plasma diagnostics
La tesi descrive diversi metodi di stima e monitoraggio di grandezze di plasma utilizzabili anche per applicazioni di controllo in retroazione. Informazioni in tempo reale sullo stato del plasma sono necessarie per l’operazione di qualsiasi dispositivo Tokamak. In piccole macchine, come ISTTOK e Golem il controllo della posizione del centroide della corrente di plasma è sufficiente poiché i flussi termici sono bassi e il plasma si trova in regime “limiter”. In dispositivi più grandi, come RFX-mod, TCV o ASDEX-Upgrade caratterizzati da più complesse forme di plasma e da più elevati flussi termici sulla prima parete, è necessario stimare e controllare la forma del plasma e la localizzazione della deposizione del carico termico sulla prima parete (“strike points” nei regimi con divertore e punto di contatto plasma-parete nei regimi con “limiter”). I risultati degli impulsi di plasma sono anche fortemente influenzati dalla forma dei profili interni di corrente e pressione. Inoltre, anche la frazione di corrente di “bootstrap”, che non può essere direttamente misurata, gioca un ruolo importante nei regimi di operazione dei Tokamak più avanzati. Queste grandezze, collegate ai profili interni, devono essere ben diagnosticate per evitare disruzioni e mitigare le instabilità MHD. La tesi affronta tutti i summenzionati livelli di complessità del controllo, partendo dai più semplici centrati intorno alla misura della posizione del centroide della corrente di plasma in ISTTOK, presentando poi più elaborati metodi di monitoraggio in tempo reale dell’equilibrio e della forma di plasma fino agli strumenti più avanzati per la ricostruzione dei profili interni di plasma, per la mitigazione delle instabilità e per evitare le disruzioni. In questa tesi vengono forniti originali contributi a ciascun gruppo di questi metodi. La prima parte della tesi tratta della misura in tempo reale della posizione del centroide della corrente di plasma in ISTTOK. Nell’ambito di questo lavoro è stato necessario risolvere due problemi principali. Il primo, comune alla maggiore parte dei piccoli dispositivi con una scocca altamente conduttiva, è collegato agli effetti delle correnti parassite indotte nelle strutture conduttive, che alterano il segnale delle diagnostiche magnetiche e, conseguentemente, rendono inutilizzabile la misura della posizione del centroide della corrente di plasma. Questo problema è stato risolto grazie all’implementazione in tempo reale di un semplice modello alle variabili di stato che considera la presenza sia della camera da vuoto sia della scocca ed è in grado di rimuovere l’effetto delle correnti parassite da tutti i 12 sensori magnetici installati in ISTTOK. Il metodo è stato provato anche con dati di RFX-mod e del Tokamak Golem, situato a Praga, nella Repubblica Ceca. Il secondo problema è la non accurata calibrazione delle diagnostiche magnetiche in ISTTOK. Ciò ha richiesto l’uso di un metodo semplice e meno sensibile agli errori di calibrazione. Tale metodo è stato poi validato confrontando la posizione verticale con quella stimata tramite il Fascio di Ioni Pesanti (Heavy Ion Beam). L’algoritmo risultante è sufficientemente affidabile e capace di fornire informazioni sulla posizione del centroide della corrente di plasma sia per il controllo in tempo reale sia per analisi “off-line” post-scarica. È stato inoltre proposto un metodo più avanzato per la misura della posizione del centroide della corrente di plasma da usarsi dopo il miglioramento della diagnostica magnetica programmato nel prossimo futuro. La parte successiva del lavoro è dedicata allo sviluppo degli strumenti per la ricostruzione della forma di plasma e per la misura di parametri macroscopici globali. È stata svolta su RFX-mod, attualmente il più grande dispositivo reversed field pinch (RFP), in grado di operare anche in configurazione Tokamak. In particolare, in questa seconda modalità è iniziato già da qualche anno un programma di scariche a doppio (DN) o singolo nullo (SN) con il fine di eseguire esperimenti di controllo attivo di modi MHD con plasmi in modo H. Questa parte dell’attività di ricerca si è focalizzata nello sviluppo di un algoritmo per una affidabile ricostruzione del contorno di plasma, da utilizzarsi sia in tempo reale che “off-line” in RFX-mod. Tale algoritmo si basa sull’estrapolazione in vuoto del flusso magnetico ed è stato validato confrontandone i risultati con quelli forniti dal codice di equilibrio MAXFEA, solutore a elementi finiti dell’equazione di Grad-Shafranov. L’algoritmo fornisce risultati molto buoni (errore sotto il 2% del raggio minore di plasma) anche in presenza del limitato numero di sensori lungo la circonferenza poloidale in RFX-mod rispetto ai Tokamak standard (8 sensori biassiali per la misura delle componenti poloidale e toroidale del campo magnetico e 8 per la misura del flusso poloidale). Poiché l’algoritmo non fornisce solo la conoscenza del contorno di plasma, ma è in grado di calcolare il campo magnetico e il flusso ovunque nel vuoto, esso può essere usato per la stima di parecchi parametri di equilibrio come βp+li/2 o q95 in analisi post-scarica. Per scariche elongate, βp e li/2 possono essere separati. Il valore di βp fornito da questo algoritmo è quasi identico a quello ottenuto tramite una misura diamagnetica indipendente. L’implementazione in tempo reale ha permesso il calcolo dei segnali di retroazione del sistema di controllo della forma di plasma progettato per l’esecuzione delle scariche con doppio o singolo nullo. Alcuni risultati delle operazioni con controllo di forma sono riportati nella tesi. Il lavoro iniziale sulla ricostruzione e il controllo in tempo reale della forma di plasma hanno aperto la strada agli esperimenti di transizione L-H in scariche puramente ohmiche. Questi esperimenti non hanno mostrato prove di accesso al modo H né durante la fase stazionaria né in quelle transitorie (principalmente crescita e decrescita della corrente) della scarica. Tuttavia, poiché il controllo in retroazione della densità di plasma è stato migliorato in modo significativo, la possibilità di accedere al modo H in scariche puramente ohmiche non è esclusa in campagne future. Dopo questi tentativi iniziali senza buon esito, gli sforzi si sono concentrati sulla possibilità di ottenere la transizione L-H indotta da elettrodo di polarizzazione. Questi esperimenti hanno avuto successo, essendo stati osservati parecchi chiari segni di transizione L-H: la ripida caduta del segnale H alpha, l’incremento della densità di plasma e la formazione del piedistallo al bordo. La descrizione di questi esperimenti è presentata nella tesi. L’ultima parte della tesi è stata dedicata ad uno strumento in corso di sviluppo per migliorare gli attuali metodi di controllo dei profili di corrente, temperatura, pressione di plasma e prevenzione delle disruzioni, denominato RApid Plasma Transport simulatOR (RAPTOR). Questo codice fa da complemento a un semplice insieme di diagnostiche in tempo reale e calcola le informazioni mancanti utilizzando un ridotto insieme di equazioni di trasporto. La tesi contiene la descrizione del codice, specialmente le semplificazioni fisiche fatte per soddisfare i requisiti di velocità di calcolo posti da un’applicazione in tempo reale, e presenta possibili applicazioni nel campo della predizione e prevenzione delle disruzioni. Esperimenti dedicati sono stati eseguiti in RFX-mod per provare un metodo di predizione delle disruzioni dovute alle instabiltà Resistive Wall Mode (RWM) in scariche con q(a)<2 e in TCV per la predizione di disruzioni dovute a limite di densità. In entrambe le classi di disruzione, i profili con denti di sega sono modificati significativamente prima della disruzione, ma la modifica non si riflette nella predizione di RAPTOR. Perciò il periodo dei denti di sega è stato usato come variabile di retroazione: una grande discrepanza tra RAPTOR e il periodo sperimentale dei denti di sega attiva l’allarme di disruzione. Gli esperimenti hanno mostrato che RAPTOR nel suo attuale stato di sviluppo è un valido strumento per la predizione delle disruzioni in plasma ohmici in modo L senza significative variazioni di forma: in RFX-mod, l’allarme di disruzione fu attivato parecchie decine di millisecondi prima della disruzione stessa e in TCV centinaia di millisecondi prima. Il maggiore vantaggio di questo metodo consiste nel suo essere basato sulla fisica del fenomeno, quindi non richiede enormi quantità di dati di scariche per addestrare reti neurali come gli attuali algoritmi. Esso è anche trasferibile da un dispositivo ad un altro, a differenza degli attuali strumenti di predizione delle disruzioni. Tuttavia i futuri strumenti di prevenzione delle disruzioni dovranno essere in grado di trattare plasmi molto più complessi di quelli studiati in questi casi di scariche in modo L ohmiche. L’ultima sezione di questa tesi dà esempi di predizione di disruzione in ASDEX-Upgrade e identifica le lacune che debbono essere colmate prima che RAPTOR diventi un strumento di predizione delle disruzioni pienamente maturo. Prima di tutto, sarà necessario includere tutte le sorgenti di riscaldamento e sostenimento della corrente (“current drive”). Un secondo importante aspetto è l’inclusione della pressione degli ioni veloci, che contribuisce in modo significativo alla totale energia di plasma e influenza la dinamica dei modi MHD, per esempi stabilizzando i denti di sega. Un altro importante pezzo del puzzle è l’accoppiamento di un solutore dell’equazione di Grad-Shafranov in tempo reale con RAPTOR, che può migliorare la qualità della ricostruzione dell’equilibrio, collegata da vicino, per esempio, al controllo delle instabilità NTM. Ultimo, ma non meno importante, un enorme beneficio potrebbe essere ottenuto da una migliore stima in tempo reale del profilo di temperatura elettronica fornita dalla relativa diagnostica.

The White-bellied Sea-Eagle Haliaeetus leucogaster is widespread in Australia, but has been the subject of conservation concern due to suggested localised declines and extinctions. Regionalised monitoring programmes have addressed some aspects of local concern, however a broader approach is needed to gain an understanding of large-scale processes affecting long-term persistence at scales equivalent to the species Australian range. Ultimately, the ability to predict change in population size over time accurately depends on the scale of analysis. By necessity, ecological studies using direct sampling techniques are often made across spatial scales smaller than a species geographic range and across relatively short time frames. This seems counter-intuitive considering that long-term species persistence is often dependent on large-scale processes. The principal aim of this thesis was to identify historical and contemporary forces responsible for the current pattern of population structure in H. leucogaster. This required a multi-scale approach, and the resulting research uses genetic, distributional and morphometric data. Haliaeetus leucogaster is a large territorial raptor that historically has been associated with coastal regions, lakes and perennial river systems. It has an extensive worldwide distribution from the western coast of India throughout the Indomalaysian region, Papua New Guinea and Australia. By virtue of the species' large-scale distribution, in Australia it is fairly cosmopolitan in its use of habitat and prey types. Haliaeetus leucogaster is monomorphic for adult plumage colouration, but in body size displays reversed sexual dimorphism with female birds significantly larger. A discriminant function based on 10 morphometric characters was 100% effective in discriminating between 19 males and 18 females that had been sexed using molecular genetic methods. Re-classification using a jackknife procedure correctly identified 92% of individuals. The discriminant function should be a viable alternative to genetic sexing or laparoscopy for a large proportion of individuals within the Australo-Papuan range of this species; and can also be used to identify a small proportion of "ambiguous" individuals for which reliable sexing will require those other techniques. I used mitochondrial (mtDNA) control region sequence data to investigate the current distribution of genetic variation in this species at the continental level and within and between specified regional units. I was specifically interested in identifying breaks in genetic connectivity between the west and east of the continent and between Tasmania and the Australian mainland. Overall, genetic diversity was low and there was no significant level of genetic subdivision between regions. The observed genetic distribution suggests that the population expanded from a bottleneck approximately 160 000 years ago during the late Pleistocene, and spread throughout the continent through a contiguous range expansion. There is insufficient evidence to suggest division of the population into different units for conservation management purposes based on the theoretical definition of the 'evolutionary significant unit'. It is clear from the analysis that there are signatures of both historical and contemporary processes affecting the current distribution. Given the suggestion that population expansion has been relatively recent, additional sampling and confirmation of the perceived pattern of population structure using a nuclear marker is recommended to validate conservation monitoring and management at a continental scale. To determine the existence of perceived population declines across ecological time scales, I analysed the Australian Bird Atlas Data to identify the extent and pattern of change in range and density of the species between three Atlas Periods (1901-1976, 1977-1981 and 1998-2001) using a new standardised frequency measure, the Occupancy Index (OI) for 1° blocks (approx. 100km2) across the continent. At the continental scale, there was no significant difference in the spatial extent of occupancy between Atlas Periods. However, there were considerable changes in frequency and range extent between defined regions, and there were distinct differences in the pattern of change in OI between coastal and inland blocks over time. Coastal blocks showed much more change than inland blocks, with a clear increase in the use of coastal blocks, accompanied by a decrease in inland blocks, during the 1977-1981 Atlas Period, relative to both other Atlas Periods. The over-riding factor associated with distributional shifts and frequency changes was apparently climatic fluctuation (the 1977-1981 period showing the influence of El Nino associated drought). The impression of abundance was strongly dependent on both the temporal and spatial scale of analysis. To test for correspondence between geographic variation in morphology and geographic variation in mtDNA I analysed morphometric data from 95 individuals from Australia and Papua New Guinea. First, the degree of morphometric variation between specified regions was determined. This was then compared with the pattern of genetic differentiation. There was a strong latitudinal cline in body dimensions. However, there was no relationship between morphometric variation and patterns of genetic variation at least for mtDNA. Females showed a pattern of isolation by distance based on morphometric characters whereas males did not. Three hypotheses to explain the pattern of morphometric variation were considered: phenotypic plasticity, natural selection and secondary contact between previously isolated populations. I conclude that the pattern of morphometric variation is best explained by the suggestion that there is sufficient local recruitment for natural selection to maintain the observed pattern of morphometric variation. This implies that gene flow may not be as widespread as the mtDNA analysis suggested. In this instance either the relatively recent colonisation history of the species or the inability of the mtDNA marker to detect high mutation rates among traits responsible for maintaining morphometric variation may be overestimating the levels of mixing among regions. As might be expected given the physical scale over which this study was conducted, the pattern of genetic, morphometric and physical distribution varied dependent on the scale of analysis. Regional patterns of genetic variation, trends in occupancy and density and morphometric variation did not reflect continental patterns, reinforcing the contention that extrapolation of data from local or regional levels is often inappropriate. The combined indirect methodologies applied in this study circumvent the restrictions imposed by direct ecological sampling, because they allow survey across large geographic and temporal scales effectively covering the entire Australian range of H. leucogaster. They also allow exploration of the evolutionary factors underpinning the species' current distribution.

The White-bellied Sea-Eagle Haliaeetus leucogaster is widespread in Australia, but has been the subject of conservation concern due to suggested localised declines and extinctions. Regionalised monitoring programmes have addressed some aspects of local concern, however a broader approach is needed to gain an understanding of large-scale processes affecting long-term persistence at scales equivalent to the species Australian range. Ultimately, the ability to predict change in population size over time accurately depends on the scale of analysis. By necessity, ecological studies using direct sampling techniques are often made across spatial scales smaller than a species geographic range and across relatively short time frames. This seems counter-intuitive considering that long-term species persistence is often dependent on large-scale processes. The principal aim of this thesis was to identify historical and contemporary forces responsible for the current pattern of population structure in H. leucogaster. This required a multi-scale approach, and the resulting research uses genetic, distributional and morphometric data. Haliaeetus leucogaster is a large territorial raptor that historically has been associated with coastal regions, lakes and perennial river systems. It has an extensive worldwide distribution from the western coast of India throughout the Indomalaysian region, Papua New Guinea and Australia. By virtue of the species' large-scale distribution, in Australia it is fairly cosmopolitan in its use of habitat and prey types. Haliaeetus leucogaster is monomorphic for adult plumage colouration, but in body size displays reversed sexual dimorphism with female birds significantly larger. A discriminant function based on 10 morphometric characters was 100% effective in discriminating between 19 males and 18 females that had been sexed using molecular genetic methods. Re-classification using a jackknife procedure correctly identified 92% of individuals. The discriminant function should be a viable alternative to genetic sexing or laparoscopy for a large proportion of individuals within the Australo-Papuan range of this species; and can also be used to identify a small proportion of "ambiguous" individuals for which reliable sexing will require those other techniques. I used mitochondrial (mtDNA) control region sequence data to investigate the current distribution of genetic variation in this species at the continental level and within and between specified regional units. I was specifically interested in identifying breaks in genetic connectivity between the west and east of the continent and between Tasmania and the Australian mainland. Overall, genetic diversity was low and there was no significant level of genetic subdivision between regions. The observed genetic distribution suggests that the population expanded from a bottleneck approximately 160 000 years ago during the late Pleistocene, and spread throughout the continent through a contiguous range expansion. There is insufficient evidence to suggest division of the population into different units for conservation management purposes based on the theoretical definition of the 'evolutionary significant unit'. It is clear from the analysis that there are signatures of both historical and contemporary processes affecting the current distribution. Given the suggestion that population expansion has been relatively recent, additional sampling and confirmation of the perceived pattern of population structure using a nuclear marker is recommended to validate conservation monitoring and management at a continental scale. To determine the existence of perceived population declines across ecological time scales, I analysed the Australian Bird Atlas Data to identify the extent and pattern of change in range and density of the species between three Atlas Periods (1901-1976, 1977-1981 and 1998-2001) using a new standardised frequency measure, the Occupancy Index (OI) for 1° blocks (approx. 100km2) across the continent. At the continental scale, there was no significant difference in the spatial extent of occupancy between Atlas Periods. However, there were considerable changes in frequency and range extent between defined regions, and there were distinct differences in the pattern of change in OI between coastal and inland blocks over time. Coastal blocks showed much more change than inland blocks, with a clear increase in the use of coastal blocks, accompanied by a decrease in inland blocks, during the 1977-1981 Atlas Period, relative to both other Atlas Periods. The over-riding factor associated with distributional shifts and frequency changes was apparently climatic fluctuation (the 1977-1981 period showing the influence of El Nino associated drought). The impression of abundance was strongly dependent on both the temporal and spatial scale of analysis. To test for correspondence between geographic variation in morphology and geographic variation in mtDNA I analysed morphometric data from 95 individuals from Australia and Papua New Guinea. First, the degree of morphometric variation between specified regions was determined. This was then compared with the pattern of genetic differentiation. There was a strong latitudinal cline in body dimensions. However, there was no relationship between morphometric variation and patterns of genetic variation at least for mtDNA. Females showed a pattern of isolation by distance based on morphometric characters whereas males did not. Three hypotheses to explain the pattern of morphometric variation were considered: phenotypic plasticity, natural selection and secondary contact between previously isolated populations. I conclude that the pattern of morphometric variation is best explained by the suggestion that there is sufficient local recruitment for natural selection to maintain the observed pattern of morphometric variation. This implies that gene flow may not be as widespread as the mtDNA analysis suggested. In this instance either the relatively recent colonisation history of the species or the inability of the mtDNA marker to detect high mutation rates among traits responsible for maintaining morphometric variation may be overestimating the levels of mixing among regions. As might be expected given the physical scale over which this study was conducted, the pattern of genetic, morphometric and physical distribution varied dependent on the scale of analysis. Regional patterns of genetic variation, trends in occupancy and density and morphometric variation did not reflect continental patterns, reinforcing the contention that extrapolation of data from local or regional levels is often inappropriate. The combined indirect methodologies applied in this study circumvent the restrictions imposed by direct ecological sampling, because they allow survey across large geographic and temporal scales effectively covering the entire Australian range of H. leucogaster. They also allow exploration of the evolutionary factors underpinning the species' current distribution.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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