Thèses sur le sujet « Ossicle »

La Sindrome di Shwachman (SDS) è una rara malattia genetica, autosomica recessiva, caratterizzata da insufficienza pancreatica, disfunzioni ematologiche, displasie scheletriche e disordini cognitivi. Nel 90% dei pazienti vengono riscontrate mutazioni a carico del gene SBDS. Similarmente ad altre sindromi midollari, i pazienti affetti da SDS hanno un aumentato rischio di insorgenza di mielodisplasie e leucemia, ma i meccanismi responsabili di questa predisposizione non sono ancora stati indagati in modo approfondito. Le cellule mesenchimali stromali (MSCs) vengono considerate fattori con un ruolo fondamentale nel mantenere e sostenere la plasticità e la sopravvivenza delle cellule staminali all’interno della nicchia midollare. Studi recenti hanno dimostrato inoltre come mutazioni specifiche a livello delle MSCs possono essere fattori sufficienti per disregolare i sottili equilibri omeostatici all’interno della nicchia e dare inizio ad un processo di trasformazione neoplastica. Il nostro gruppo ha dimostrato che MSCs derivate da pazienti affetti da SDS erano comparabili a quelli di donatori sani per quanto riguarda le loro caratteristiche in vitro (marcatori di superficie, capacità di differenziare in diversi lineages, abilità nel sostenere la vitalità di cellule CD34). La gene expression analysis condotta su 16 SDS-MSCs in realtà mostra come queste cellule avessero un pattern di espressione genica differente da quello delle mesenchimali di donatori sani, suggerendo come le mesenchimali SDS potessero avere un ruolo nei disordini ematologici riscontrati nella malattia. In questo studio abbiamo aumentato la corte di pazienti e, avvalendoci di un modello in vivo, abbiamo studiato il possibile coinvolgimento delle MSCs nei disordini ematopoietici. Il nostro modello prevedeva l’impianto sottocutaneo in topi immunocompromessi di pellet cartilaginei derivanti da MSCs da donatori sani e pazienti stimolate per 21 giorni con un particolare medium di differenziamento. Dopo 60 giorni, gli animali sono stati sacrificati e gli ossicoli recuperati per l’analisi istologica. Dai nostri dati emerge come, al termine del periodo sperimentale, solo i pellet derivati da MSCs di donatore sano siano stati in grado di formare una nicchia midollare completa, con presenza di trabecole ossee, adipociti e cellule ematopoietiche murine. Di contro, nessuno dei pellet derivati da paziente è stato ritrovato vascolarizzato o colonizzato da cellule ematopoietiche. L’analisi a time point precoci ci ha permesso di individuare dei difetti nel processo differenziativo dei pellet derivati da pazienti, che non mostravano riassorbimento cartilagineo, né deposizione di matrice ossea o processi di vascolarizzazione. Questo dato ci suggerisce come nel nostro modello le mesenchimali da paziente mostrino difetti nel loro processo differenziativo e di conseguenza possano essere coinvolte anche nei disordini ematologici a carico del midollo. Nella seconda parte del nostro studio abbiamo testato un farmaco su cellule ematologiche e non ematologiche di paziente. Questo farmaco agisce sulle nonsense stop codon mutation, una delle mutazioni più diffuse nei pazienti SDS a carico del gene SBDS, consentendo il read-through della mutazione non senso e quindi la produzione di una proteina completa. I nostri risultati hanno mostrato l’azione positiva di questo farmaco in diverse linee cellulari (linfoblastoidi, mesenchimali e mononucleate da midollo), restorando la produzione della proteina. Inoltre, il trattamento con questo farmaco ha anche prodotto miglioramenti a livello funzionale nelle cellule mononucleate. In particolare queste cellule, in seguito al trattamento, hanno mostrato un significativo aumento nella capacità di dare colonie CFU-GM. Questo risultato ha forti conseguenze a livello clinico poiché, non avendo mostrato effetti tossici, questo farmaco potrebbe essere proposto per la cura dei disordini ematologici in questi pazienti.
Shwachman-Diamond Syndrome (SDS) is a rare autosomal recessive disease, characterized by exocrine pancreatic disorder, hematological aberrancies, bone marrow failure and cognitive impairment. In 90% of patients the SBDS gene is found mutated. Similar to other marrow failure syndromes, SDS patients have an increased risk for developing myelodysplastic syndrome and AML. To date, the mechanisms underlying the bone marrow failure in SDS patients are not fully understood. Microenvironment constituents and in particular mesenchymal stromal cells (MSCs) are considered the pivotal organizers for the generation, maintenance and plasticity of the hematopoietic stem cell niche. Recent studies show that specific changes in MSCs may be sufficient to initiate a complex phenotype of disordered homeostasis with similarities to myelodysplasia. We have demonstrated that MSCs obtained from SDS patients were comparable in vitro to HD but gene expression analysis of 16 SDS-MSCs showed that these cells had a specific gene expression signature compared to HD. These results suggest that it is possible that MSCs could be involved in the pathogenesis of the SDS marrow disorders. We increased our patients cohort and investigated whether SDS-MSCs were able to sustain malignant evolution using an innovative scaffold-free in vivo system based on the ex vivo generation of semi-cartilaginous pellets (SCPs) from human MSCs. We obtained SCPs stimulating MSCs for 21 days with a specific differentiating medium and a complete and correct formation of cartilaginous tissues both in HD and SDS samples. These SCPs were transplanted heterotopically into subcutaneous tissue of immunocompromised mice. After 60 days, we sacrificed mice and collected ossicles. We found that in 90% of cases, HD were able to recreate the hematopoietic microenvironment, with the establishment of a complete marrow niche, while none of the transplanted SDS-SCPs was able to recreate the hematopoietic microenvironment, revealing a defect in these differentiating process. The second part of our study was focused on testing a specific drug able to act on nonsense stop codon mutation, one of the most diffuse alterations in SDS patients, linked to risk of developing myelodysplastic syndrome. We successfully obtained restoration of SBDS protein in different cell lineages deriving from patients (Lymphoblastoids, MSCs, mononuclear cells from bone marrow). Protein restoration was also accompanied in some cases with an improvement of functionality. In particular, mononuclear cells from bone marrow treated with drug showed an increase in their ability to form colonies when cultured in a specific assay. This represents a powerful result, due to the potential clinical consequences related to possible therapeutic strategy. Indeed, SDS patients in future could take advantage of this drug to ameliorate their hematological defects and abolish other symptoms.

Магістерська дисертація: загальний обсяг 108 с., основна частина 102 с. 15 табл., 22 рис., 37 джерел. Магістерська дисертація присвячена висвітленню перспективних методів визначення акустичних характеристик та підбору протезів кісточок середнього вуха людини. Стрімкий розвиток сучасних технологій зумовлює нові виклики як для здоров’я людини, так і до осучаснення існуючих методів та технологій його покращення. Це стосується і оторилогічних захворювань, а проблема освоєння і вдосконалення тимпанопластики зумовлює актуальність даного дослілження. Метою магістерської дисертації є дослідити проблему вибору матеріалу імплантатів (протезів) на основі формули середнього вуха людини в нормі. Відповідно до мети роботи, визначено основні завдання дослідження: 1. Дослідити фізичні передумови та принципи вимірювання імпедансу середнього вуха людини. 2. Описати теоретично і підтвердити експериментально формулу середнього вуха людини в нормі. 3. Проаналізувати історію розвитку тимпанопластики, її методи, матеріали та їх акустичні характеристики. 4. Обгрунтувати вибір матеріалів імплантатів (протезів) для заміни слухових кісточок із застосуванням моделі середнього вуха. Об'єктом дослідження є процес трансформації енергії слуховим трактом людини. Предметом дослідження виступають слухові протези для заміни слухових кісточок. Методи дослідження. В роботі використано математичну модель середнього вуха людини в нормі, побудовану на основі методу електромеханічних аналогій. За допомогою методів неруйнівного контролю було визначено акустичні характеристики матеріалів імплантатів (протезів), розроблено алгоритм підбору матеріалів імплантатів (протезів), оснований на формулі середнього вуха людини. Практичне значення одержаних результатів. Отримані результати вимірювання виміру твердості та жорсткості протезів підтверджують вірність і практичну користь даної методики та уможливлює його подальше впровадження в медичних закладах.
Master's thesis: pages, total – 108, main body – 102; 15 tables, 22figures, 37 references. This master's thesis investigates prospective techniques for determining acoustic characteristics and the middle ear ossicles prosthetics selection. The rapid development of modern technologies leads to new challenges both for human health and for the modernization of existing techniques and methods for its improvement. This also applies to otorhinolaryngological diseases, and the issue of mastering and improving tympanoplasty determines the relevance of this study. The purpose of this master's thesis is to study the problem of selecting the material for implants (prostheses) based on the formula of the middle ear in the norm. In accordance with the purpose of the work, the main objectives of the study are defined: 1. To study the physical preconditions and principles of measuring the impedance of human’s middle ear. 2. To Describe theoretically and confirm experimentally the formula of the middle ear in the norm. 3. To analyze the history of the development of tympanoplasty, its methods, materials, and their acoustic characteristics. 4. To substantiate the choice of materials for implants (prostheses) to replace auditory ossicles using the model of the middle ear. The object of research is the process of energy transformation by the human’s auditory tract. The subject of the study is the auditory prostheses that replace auditory ossicles. Research methods. The mathematical model of the human’s middle in norm is used in this paper and is based on the method of electromechanical analogies. With the help of non-destructive testing techniques, acoustic characteristics of implant materials (prostheses) were determined, an algorithm based on the human’s formula of the middle ear to select materials for implants (prostheses) was developed. The practical value of the results. The obtained results of measurements of hardness and rigidity of prostheses confirm the fidelity and practical utility of this methodology and allow its further implementation in medical institutions.
Магистерская диссертация посвящена освещению перспективных методов определения акустических характеристик и подбора протезов косточек среднего уха человека. Стремительное развитие современных технологий обусловливает новые вызовы как для здоровья человека, так и к осовременивания существующих методов и технологий его улучшение. Это касается и оторилогичних заболеваний, а проблема освоения и совершенствования тимпанопластике обуславливает актуальность данного дослилження. Целью магистерской диссертации является исследовать проблему выбора материала имплантатов (протезов) на основе формулы среднего уха человека в норме. В целях работы, определены основные задачи исследования: 1. Исследовать физические предпосылки и принципы измерения импеданса среднего уха человека. 2. Описать теоретически и подтвердить экспериментально формулу среднего уха человека в норме. 3. Проанализировать историю развития тимпанопластике, ее методы, материалы и их акустические характеристики. 4. Обосновать выбор материалов имплантатов (протезов) для замены слуховых косточек с применением модели среднего уха. Объектом исследования является процесс трансформации энергии слуховым трактом человека. Предметом исследования выступают слуховые протезы для замены слуховых косточек. Методы исследования. В работе использованы математическую модель среднего уха человека в норме, построенную на основе метода электромеханических аналогий. С помощью методов неразрушающего контроля были определены акустические характеристики материалов имплантатов (протезов), разработан алгоритм подбора материалов имплантатов (протезов), основанный на формуле среднего уха человека. Практическое значение полученных результатов. полученные результаты измерения измерения твердости и жесткости протезов подтверждают верность и практическую пользу данной методики и делает его дальнейшее внедрение в медицинских учреждениях.

Le ossime sono composti molto importanti per molti usi a livello industriale, da additivi per le vernici a farmaci e pesticidi. Tuttavia la più rilevante è la cicloesanoneossima dalla quale mediante riarrangiamento di beckman si ottiene il caprolattame a sua volta usato per la sintesi di nylon-6. Lo studio dell'idrogenazione di diversi nitrocomposti aromatici ha mostrato che essi si idrogenano alle ammine corrispondenti con consecutiva ossimazione. I catalizzatori utilizzati sono a base di palladio, in particolare si è usato il catalizzatore di palladio supportato su carbone, le temperature si aggirano tra i 50 e i 60°C con pressioni di circa 10 bar di idrogeno.

Yes
Background: Carbon (δ13C) and nitrogen (δ15N) isotope ratios of collagen from teeth and bone are used to study human nutrition and health. As bones are constantly remodelling throughout life, isotopic values of bone collagen represent an average of several years. In contrast, human teeth do not remodel and their primary dentine contains only the isotopic data from the time of formation. In contrast to all other bones, human auditory ossicles also appear not to remodel. As they develop in utero and finish formation in the first 2 years of life, their collagen should also represent isotopic values of these two relatively short periods. Aim: By comparing δ13C and δ15N data from ossicles and incremental dentine, this study aims to investigate how two developmental periods of the ossicles, in utero and the first 2 years of life, reflect in collagen obtained from the ossicles. Subject and methods: Ossicle and tooth samples of 12 individuals aged 0.5 ± 0.4 years to 13 ± 1 years from the nineteenth century St. Peter’s burial ground in Blackburn were collected and processed to obtain bulk bone and incremental dentine collagen which was measured for δ13C and δ15N. Results: Averaged δ13C and δ15N of ossicles are lower when compared to every age group except after 3 years of age. Average offset between ossicles and dentine of different groups ranges from 0.4–0.9‰ for δ13C and from 0.3–0.9‰ for δ15N, with highest counterbalance at birth and after the first 5 months after birth. Conclusions: There appears to be a systematic offset between the dentine and ossicle data. It seems that the second phase of development does not influence the isotopic values of collagen significantly and the data we are obtaining from ossicles represents the in utero period.
Research grant from The Society for the Study of Human Biology.

Thesis advisor: Noah P. Snyder
Land cover and climate changes, attributed to natural and anthropogenic forcings, cause deviations in geomorphic processes that act to deliver sediment from watersheds to lakes. In New England, contradictory evidence exists as to the influence of deforestation associated with EuroAmerican settlement and major flood events on watershed erosion rates over the past ~250 years. Through combining sediment core analysis from Ossipee Lake, New Hampshire with geomorphic analysis of the Ossipee Lake watershed, this study quantifies Holocene through Anthropocene watershed erosion rates, and assesses variations in rates in relation to short-term historic events such as major storm events or deforestation, and long-term variations related to natural climate variability and post-glacial landscape evolution. An 8.63 m core was collected and spans the entire period from deglaciation to present. Bulk composition and age-depth modeling, utilizing both short-lived radioisotopes and radiocarbon dating, are used to quantify changes in deposition and inferred erosion rates over time. Additional insight on sedimentary processes is provided by measurements of magnetic susceptibility and bulk geochemistry. Lake-sediment data suggests clastic sediment mass accumulation rates vary between 0.0032 to 0.5870 g/cm2/yr, with deposits of increased terrestrially derived sediment focused between ~8500 to 7800, ~6500 to 2500, and 1600 cal yr BP to present. Geomorphic analysis is used to identify regions within the watershed that act to deliver sediment to Ossipee Lake. Potential sources of sediment supply include loose, unconsolidated proglacial deposits near Ossipee Lake that transition to primarily till in upland areas. Calculated bed shear stress along rivers highlights areas in the watershed capable of transporting sediment and areas that can serve as traps thus limiting sediment delivery to Ossipee Lake
Thesis (MS) — Boston College, 2019
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Earth and Environmental Sciences

GNU Radio and OSSIE (Open-Source SCA (Software communication architecture) Implementation-Embedded) are two open source software toolkits for SDR (Software Defined Radio) developments, both of them can be supported by USRP (Universal Software Radio Peripheral). In order to compare the performance of these two toolkits, an FM receiver over GNU Radio and OSSIE are tested in my thesis, test results are showed in Chapter 4 and Chapter 5. Results showed that the FM receiver over GNU Radio has better performance, due to the OSSIE is lack of synchronization between USRP interface and the modulation /demodulation components. Based on this, the SISO (Single Input Single Output) communication system over GNU Radio is designed to transmit and receive sound or image files between two USRP equipped with RFX2400 transceiver at 2.45G frequency. Now, GNU Radio and OSSIE are widely used for academic research, but the future work based on GNU Radio and OSSIE can be designed to support MIMO, sensor network, and real time users etc.

Gorgonocephalus eucnemis, Ophiothrix suensonii and Ophiothrix spiculata are aerobic Echinoderms. Previous observations on the anatomy of these two genera state five pairs of radial shields and genital plates are responsible for regulating the position of the roof of the body disc and the flushing of water in and out of the bursae. Rates of bursal ventilation increase by an average 60-64% when the ophiuroid is exposed to an increase in food or a decrease in dissolved oxygen in Gorgonocephalus. When exposed to hypoxic oxygen concentrations O. suensonii and O. spiculata increased bursal-ventilation rates by (means of) 35% and 28%. Measurements of DO from inside and outside the bursae show that DO is being absorbed during bursal-ventilations. These findings suggest bursal ventilation is a means of respiration and increased rates of bursal-ventilation may help meet increased oxygen demands during feeding and some periods of hypoxia. This dissertation includes unpublished, co-authored material.

Software Defined Radios (SDRs) are redefining the current landscape of wireless communications in both military and commercial sectors. The rapidly evolving capabilities of digital electronics are making it possible to execute significant amounts of signal processing on general purpose processors ratherthan using special-purpose hardware.

As a consequence of the availability of SDR, applications can be used to implement flexible communication systems in an operating prototype within a very short time. However, the initial lack of standards and design rules leads to incompatibility problems when using products from different manufacturers. This problem is critical for the military and public safety sectors, for this reason the US Army was interested in SDR and carried out research into the specification of a common software infrastructure for SDR. This initiative started in the mid-1990s and evolved into the Software Communications Architecture (SCA).

SCA is a non-proprietary, open architecture framework that allows a designer to design interoperable and platform independent SDR applications. At the same time the SCA framework, by abstracting the radio communication system, speeds up waveform development because developers no longer have to worry about hardware details.

This thesis project uses OSSIE, an open source SCA implementation, to illustrate the process of developing a waveform. Today companies are exploiting open source solutions and investing money to evaluate and improve available technologies rather than developing their own solutions: OSSIE provides a working SCA framework without any license cost. OSSIE also provides some tools to develop SCA waveforms. Of course open source software comes with some limitations that a designer must take into account. Some of these limitations will be described for OSSIE (specifically the limited documentation and lack of libraries), along with some suggestions for how to reduce their impact.

This thesis project shows in detail the development process for SCA waveforms in OSSIE. These details are examined in the course of successfully implementing a target waveform to enable the reader to understand the advantagies and disadvantages of this technology and to facilitate more people using OSSIE to develop waveforms. Although a waveform was successfully implemented there were unexpected issues with regard to the actual behavior of the waveform when implemented on the hardware used for testing.

QC 20100831

A very basic engineering tradeoff is performance versus flexibility and this design choice must be made when developing a software radio. Hardware devices such as General Purpose Processors (GPPs), Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs) and Application Specific Integrated Circuits (ASICs) all provide a designer with choices along the performance versus flexibility spectrum. The designer must choose a combination of GPP, DSP, FPGA and ASIC devices to balance the needs of performance versus flexibility. The Software Communications Architecture (SCA) is a specification for a software radio architecture produced by the Joint Program Executive Office (JPEO) Joint Tactical Radio System (JTRS). The 2.2 revision of the SCA only implies support for GPPs, with no specified support for additional devices such as FPGAs. However, FPGA integration within the scope of the SCA is still possible. The integration of an additional processing hardware device other than a GPP requires the ability to logically represent the device within the Core Framework. This representation is implemented within the OSSIE Core Framework, an open source implementation of the SCA. The representation requires the support of multiple implementations of signal processing components within the framework, a simple component deployment model, and the abstraction of the FPGA interactions into a software component.
Master of Science

As the complexity of software increases, so does the complexity of software testing. This challenge is especially true for modern military communications as radio functionality becomes more digital than analog. The Software Communications Architecture was introduced to manage the increased complexity of software radios. But the challenge of testing software radios still remains. A common methodology of software testing is the unit test. However, unit testing of software assumes that the software under test can be decomposed into its fundamental units of work. The intention of such decomposition is to simplify the problem of identifying the set of test cases needed to demonstrate correct behavior. In practice, large software efforts can rarely be decomposed in simple and obvious ways. In this paper, we introduce the fuzzing methodology of software testing as it applies to software radios. Fuzzing is a methodology that acts only on the inputs of a system and iteratively generates new test cases in order to identify points of failure in the system under test. The REDHAWK implementation of the Software Communications Architecture is employed as the system under test by a fuzzing framework called Peach. Fuzz testing of REDHAWK identified a software bug within the Core Framework, along with a systemic flaw that leaves the system in an invalid state and open to malicious use. It is recommended that a form of Fault Detection be integrated into REDHAWK for collocated processes at a minimum, and distributed processes at best, in order to provide a more fault tolerant system.
Master of Science

The Software Communications Architecture (SCA) specification defines a framework that allows modular software components to be developed and assembled to build larger radio applications. The specification allows for these components to be distributed among a set of computing hardware and to be connected by standard interfaces. This research aims to build a spatially distributed SCA application for the Open Source SCA Implementation: Embedded (OSSIE) implementation using low-cost Universal Software Radio Peripheral (USRP) hardware. The system collects signals from multiple spatially distributed collection devices and use those signals to compute precision estimates for the location of emitters using time difference of arrival (TDOA) computations. Several OSSIE components and tools are developed to support this research. Results are presented showing the capabilities of the geolocation system.
Master of Science

Software Defined Radios are computer based systems that emulate the behavior of traditional radio systems by processing digitized radio signals. A SDR replaces the traditional fixed hardware radio with a system that may be reconfigured, both during operation to provide greater flexibility and by providing software upgrades to add new capabilities without requiring new hardware. These are powerful reasons for using SDR technology; however this flexibility comes at the cost of increased hardware cost and greater power consumption compared with traditional hardware radios. This report presents measurements of memory and processor usage for a Software Communication Architecture (SCA) waveform running on an OMAP starter kit and a desktop PC. The process used to build software, originally targeted for a desktop computer, on an embedded machine with a different processor architecture is described. OSSIE, an open source SCA implementation developed at Virginia Tech, was ported to the ARM processor by adding support for building OSSIE into the OpenEmbedded build system. Once the port for the OMAP starter kit was complete, it became possible to easily re-target OSSIE for a variety of other hardware platforms. For testing purposes a simple waveform capable of transmitting several common digital modulation formats was developed. A SCA device for the Universal Software Radio Peripheral was developed to interface the waveform to the antenna. One method to reduce the cost and power consumption is to limit the amount of memory used in the radio. This reduces both cost and power consumption. This report describes the memory manager portion of the Linux kernel and how it helps reduce the memory used by the system. The exmap tool for accurately measuring memory usage is described and used to measure the memory usage of the OSSIE based test waveform. These techniques help radio developers measure and reduce the amount of memory required for the SDR, reducing system cost and power consumption. Finally, the oprofile was used to measure relative processor usage of the waveform components. Oprofile can also provide details about specific sections of waveform code that use the most processor cycles. This information helps the radio designer reduce the number of processing cycles required. This allows the hardware to use a lower speed part, or add more capability to the radio design.
Master of Science

Acoustically, teleost swimbladders have been considered resonant underwater bubbles. Contrary results indicating that bladders are tuned less sharply than such a bubble have been explained by damping of surrounding fish tissue. Recent findings in toadfish and weakfish, however, suggest that the bladder is a highly damped structure and that the frequency of the fish sounds is deternlined as a forced response to sonic muscle movement rather than by resonance of the bladder. In this study I examined acoustics and material properties of swimbladders in Tilapia (an auditory generalist) and the channel catfish (an auditory specialist). The swimbladder was struck with a piezoelectric impact hammer. Amplitude and timing characteristics of bladder sound and displacement were compared for strikes of different amplitudes. Most of the first cycle of sound occurs during swimbladder compression, indicating that the bladder rapidly contracts and expands as force increases during the strike. Harder hits are shorter in duration generate a similar displacement duration with an increasing number of shorter cycles and a 12-15 dB increase in sound amplitude. The frequency spectrum is broad, and the dominant frequency is driven by the strike and not the natural frequency of the bladder. The displacement waveform varies between species catfish exhibit a greater structural stiffness and lower amplitude movement and higher sound amplitude for an equivalent hammer strike. Material properties (peak load, stress, strain, Young's modulus), fiber direction (catfish only), and structural stiffiless of bladders exhibit various patterns suggesting that the bladder walls are not uniform structures. Additionally thickness varies regionally. Notably Young's modulus in both species is similar despite large difference in stress and strain. The modulus of catfish bladder increased 1600-fold when dried. Finally the bladder of both species had a high water content averaging about 70%. These data suggest that viscous damping caused by water in the bladder wall is a major factor responsible for acoustic properties of the teleost swimbladder.

Innerhalb der Decapoda stellt das Taxon Brachyura eines der artenreichsten Taxa mit bis zu 10000 Arten dar. Die Phylogenie der Brachyura wird aufgrund morphologischer und molekularer Untersuchungen seit mehr als ein Jahrhundert kontrovers diskutiert. Zur Klärung phylogenetischer Fragestellungen wurde mit den vergleichenden Untersuchungen der Magenossikel und der Magenzähne von 66 Taxa der Brachyura ein neuer phylogenetischer Ansatz gewählt. Mit Anwendung eines spezifischen Färbepigmentes, Alizarin-Rot S, konnten sechs neue Magenossikel einer bereits existierenden Nomenklatur hinzugefügt werden, so dass jetzt 41 Magenossikel für das Grundmuster der Brachyura angenommen werden können. Im Ergebnis der phylogenetischen Analyse wird ein monophyletisches Taxon Brachyura einschließlich der Taxa Dromiidae und Raninidae unterstützt. Die von Guinot (1977, 1978) als Monophyla postulierten Teiltaxa Podotremata und Heterotremata finden hier keine Unterstützung. Taxa wie Raninidae und Cymonomidae, welche aufgrund der coxalen Position ihrer Genitalporen dem Taxon Podotremata sensu Guinot zugeschrieben werden, weisen nach vorliegenden Daten eine nähere Verwandtschaft zu den "höheren" Krabben auf. Eine Monophylie eines Taxons Thoracotremata sensu Guinot kann dagegen basierend auf den analysierten Magenstrukturen, aber auch auf der Grundlage molekularer Studien (Schubart et al. 2000a, 2000b) und dem vorliegenden Daten zum Fossilbericht angenommen werden. Eine basale Stellung der Dynomenidae und Dromiidae im Ergebnis der kladistischen Analyse lässt sich mit den Fossilfunden aus dem mittleren Jura in Übereinstimmung bringen. Des weiteren kann für die meisten Taxa der "höheren" Krabben ein gemeinsamer Vorfahre für die obere Kreide bzw. bis zum Beginn des Tertiärs postuliert werden.
Within the Decapoda the taxon Brachyura is the species-richest taxon with up to 10000 species. The phylogeny of the Brachyura has been discussed based on morphological and molecular investigations since more than a century. The investigation of the foregut-ossicles and gastric-teeth of 66 brachyuran species, is a new approach to answer important phylogenetic questions. Using a specific staining pigment Alizarin Red S, six new described foregut-ossicles are added to an existing nomenclature. As a result of this method the presence of 41 foregut-ossicles is proposed for the ground pattern of the Brachyura. The cladistic analysis supports a monophyletic origin of the Brachyura including the Dromiidae and the Raninidae. The taxa Podotremata and Heterotremata, postulated as monophyletic by Guinot (1977, 1978), are not supported in the present study. The Dromiidae and Raninidae, which are placed within the Podotremata sensu Guinot, are closer related to the "higher crabs". Based on the analysed foregut-characters, several molecular studies (Schubart et al. 2000a, 2000b), and the data of the fossil record, a monophyletic origin of the Thoracotremata sensu Guinot is suggested. The analysed basal position of the Dynomenidae and Dromiidae is in agreement with the brachyuran fossil record. A common ancestor for most of the "higher" brachyuran crabs is suggested for the period between the upper Cretaceous and the beginning of the Tertiary.

For a long time radio devices have been constructed in hardware with a fixed functionality. This way of constructing radio devices is starting to change with the concept of Software Defined Radio (SDR) evolving. The SDR concept leads to more flexible and long lasting radio devices. In order to make the radio software more standardized and portable, the U.S. military has defined the Software Communication Architecture (SCA). Internal communication within the SCA is done by CORBA, which limit waveforms to be only distributed over CORBA-capable hardware. The U.S. military has defined the Modem Hardware Abstraction Layer(MHAL) to enable distribution over devices not supporting CORBA. This thesis presents an implementation of MHAL and an underlying transport mechanism based on Ethernet. The implementation is done for the OSSIE package. The implementation is evaluated both in terms of real-time and throughput performance. The results show that MHAL achieves good performance, in comparison to CORBA, and can greatly be used to distribute waveforms over both CORBA and non-CORBA capable devices.

The Software Communications Architecture (SCA) is a standard for software defined radios (SDR) designed in part to promote code reuse for long-term development. With the emergence of adaptive/cognitive radios, new SDRs that are capable of reconfiguration during runtime must be developed. One advantage of SDR development over conventional radio development can be ease of design if the proper rapid development tools are made available.

This thesis explores tools designed to help realize the construction of reconfigurable systems while promoting code-reuse within the bounds of the SCA. Developing these tools requires an understanding of the SCA as well as the Open Source SCA Implementation Embedded (OSSIE) for which they are developed. The use of CORBA to link together modularized components is also discussed. Finally, several simulations are conducted in order to approximate the amount of overhead resulting from the use of the reconfiguration tool developed (the â Connect Toolâ ).
Master of Science

In order to get a better insight into the function of the human middle ear it is necessary to simulate its dynamic behaviour by means of the finite-element method. Three-dimensional measurements of the surfaces of the tympanic membrane and of the auditory ossicles malleus, incus and stapes are carried out and geometrical models are created. On the basis of these data, finite-element models are constructed and the dynamic behaviour of the combinations tympanic membrane with malleus in its elastic suspensions and stapes with annular ligament is simulated. Natural frequencies and mode shapes are computed by modal analysis. These investigations showed that the ossicles can be treated as rigid bodies only in a restricted frequency range from 0 to 3.5 kHz
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

In order to get a better insight into the function of the human middle ear it is necessary to simulate its dynamic behaviour by means of the finite-element method. Three-dimensional measurements of the surfaces of the tympanic membrane and of the auditory ossicles malleus, incus and stapes are carried out and geometrical models are created. On the basis of these data, finite-element models are constructed and the dynamic behaviour of the combinations tympanic membrane with malleus in its elastic suspensions and stapes with annular ligament is simulated. Natural frequencies and mode shapes are computed by modal analysis. These investigations showed that the ossicles can be treated as rigid bodies only in a restricted frequency range from 0 to 3.5 kHz.
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

The idea of wireless distributed computing (WDC) is rapidly gaining recognition owing to its promising potential in military, public safety and commercial applications. This concept basically entails distributing a computationally intensive task that one radio device is assigned, among its neighboring peer radio devices. The added processing power of multiple radios can be harnessed to significantly reduce the time consumed in obtaining the results of the original complex task. Since the idea of wireless distributed computing depends on a radio device forming a network with its peers, it is imperative and necessary to have a medium access control (MAC) protocol for such networks which is capable of scheduling channel access by multiple radios in the network, ensuring reliable data transfer, incorporating rate adaptation as well as handling link failures. The thesis presented here elaborates the design and implementation of such a MAC protocol for WDC employed in a practical network of radio devices configurable through software. It also brings to light the design and implementation constraints and challenges faced in this endeavor and puts forward viable solutions.
Master of Science

La mise en évidence par la biologie moléculaire et par les données paléontologiques de l'appartenance des cétacés au groupe des artiodactyles constitue une des avancées majeures de ces 30 dernières années en mammalogie. Il n'y a cependant pas à l'heure actuelle de consensus quant aux relations phylogénétiques basales des artiodactyles fondées sur des caractères morphologiques et l'histoire évolutive du groupe est de fait, ponctuée de nombreux points d'interrogation. Cette thèse explore une source de caractères phylogénétiques prometteuse : la région auditive (os pétreux, bulle auditive, osselets de l'oreille moyenne, oreille interne) à partir notamment des nouvelles perspectives offertes par l'imagerie µCT Scan. Les principaux objectifs de cette thèse sont (1) de déterminer le signal phylogénétique porté par la région auditive chez les artiodactyles afin d’apporter une nouvelle source de caractères aux analyses et (2) d’explorer le signal écologique porté par les différents éléments de cette région sensorielle dédiée à l’audition (oreille externe, moyenne et canal cochléaire du labyrinthe osseux) et à l’équilibrioception (vestibule et canaux semi-circulaires du labyrinthe osseux). La première partie de cette thèse (I) nous emmène au Togo, où de nombreux restes inédits de la région auditive de « baleines à pattes » (Protocetidae Stromer, 1908) ont été récoltés. D’un point de vu anatomique, ces restes fossiles ont permis de documenter et de décrire pour la première fois le stapes, l’incus et le labyrinthe osseux d’un protocète ; des éléments indispensables pour comprendre leur audition. L’analyse morpho-fonctionnelle indique qu’une audition optimale était probablement possible dans l’air et dans l’eau pour ces cétacés semi-aquatiques. De plus, la morphologie de leur cochlée indique que leur capacité auditive était proche de celle de leurs cousins terrestres et que les spécialisations relatives aux capacités auditives remarquables des cétacés modernes (i.e. sensibilité aux infra- ou ultrasons) se sont opérées après la séparation historique entre les mysticètes et les odontocètes.La deuxième partie de ce travail (II) se concentre sur les origines de l’amphibiose au sein des Cetancodonta, à travers l’étude de plusieurs familles fossiles, connues pour leurs liens étroits au milieu aquatique. L’étude de la région auditive des hippopotamoïdes (Anthracotheriidae + Hippopotamidae), révèle que l’adaptation à un mode de vie semi-aquatique est apparue plusieurs fois, de façon convergente, dans son histoire évolutive et semble d’ailleurs indiquer une origine terrestre pour ce groupe. Quant au raoellidé Indohyus, son complexe pétro-tympanique présente une combinaison de caractères suggérant un certain degré d’adaptation au milieu aquatique, mais l’étude fonctionnelle de sa cochlée indique que ce taxon ne pouvait très probablement pas entendre de façon efficace sous l’eau. Pour finir, le dernier point de cette thèse explore également le potentiel phylogénétique de la région auditive à travers une analyse construite sur des caractères morphologiques du pétreux et du labyrinthe osseux à l’échelle des artiodactyles. Pour la première fois, les résultats de notre analyse concordent avec ceux des analyses moléculaires. Parmi les points les plus notables, le clade des Cetancodonta est bien soutenu par la morphologie du pétreux et la position d’Indohyus suggère fortement que les raoellidés sont des cétacés.Ainsi, la région auditive s’avère être un élément essentiel d’un point de vu phylogénétique et morphofonctionnel. En effet, comme nous avons pu le voir tout au long de cette thèse, lorsque la nature complexe et variée de la région auditive est appréhendée dans son ensemble, elle permet d’inférer l’écologie d’un taxon donné et d’en apprendre davantage sur ses relations de parenté. Par conséquent, la région auditive est encore loin d’avoir dit ses derniers mots... et nous n’avons pas encore fini d’en entendre parler
The discovery by both molecular biology and palaeontological data that cetaceans are artiodactyls constitutes one of the major breakthroughs in mammal’s evolutionary history of the past 30 years. However, no consensus has yet been reached regarding the basal relationship within the enlarged Artiodactyla clade and major questions of its evolutionary history remain to be solved. This thesis explores a promising source of phylogenetic characters: the auditory region (petrosal bone, tympanic bulla, middle ear ossicles, inner ear) from the new perspectives offered by µCT Scan imaging.The main objectives of this thesis are (1) to determine the phylogenetic signal carried by the auditory region in artiodactyls in order to provide a new source of characters to the analyses and (2) to explore the ecological signal carried by the different elements of this sensory region dedicated to hearing (outer ear, middle ear and cochlear canal of the bonny labyrinth) and to equilibrioception (vestibule and semicircular canals of the bony labyrinth).The first part of this thesis (I) brings us to Togo, where many fossil remains of the auditory region of ancient “legged whales” (Protocetida Stromer 1908) have been collected. From an anatomical viewpoint, these fossil remains document a nearly complete petrotympanic complex and allowed us to describe for the first time, the stapes, incus and bony labyrinth of a protocetid whale, which are crucial elements to understand their hearing. Morphofunctional analysis indicates that optimal hearing was probably possible both in air and underwater for these semi-aquatic whales. In addition, the morphology of their cochlea indicates that their hearing ability was close to that of their terrestrial kin and that the specializations related to the remarkable hearing abilities of modern cetaceans (i.e. sensitivity to infra- or ultrasound) occurred after the historical separation between mysticetes and odontocetes.The second part of this work (II) focuses on the origins of amphibiosis in Cetancodonta, through the study of several fossil families, known for their potamophilous tendencies. The study of the auditory region of hippopotamoids (Anthracotheriidae + Hippopotamidae) reveals that adaptation to a semi-aquatic lifestyle has emerged several times (i.e. in a convergent way) in its evolutionary history and seems to indicate a terrestrial origin for this group. As for the raoellid Indohyus, its petro-tympanic complex presents a combination of features suggesting some degree of adaptation to the aquatic environment, but the functional study of its cochlea indicates that this taxon probably could not hear efficiently underwater.The last point of this thesis explores the phylogenetic potential of the auditory region through an analysis built upon morphological characters of the petrosal and bony labyrinth at Artiodactyla scale. For the first time, the results of our analysis are consistent with that of molecular analyses. Among the most notable points, the Cetancodonta clade is well supported by the morphology of the petrosal and Indohyus’ position strongly suggests that raoellids are cetaceans.Thus, the auditory region turns out to be an essential element from a phylogenetic and morphofunctional viewpoint. Indeed, as we have seen throughout this thesis, when the complex and multifaceted nature of the auditory region is apprehended as a whole, it allows to infer the ecology of a given taxon and to clarify its phylogenetic relationships. Thus, the auditory region is still far from having said its last words… and we are not done hearing about it yet

Dissertação de mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016
The shallow waters sea cucumbers included on the Holothuria genus has become a new important fishing resource, because the overfishing on the Indo-Pacific populations and the increasing Asian demand. In spite of the importance of this group, its taxonomy has suffered several changes during the last 50 years and, nowadays, it is still under discussion. A right definition of species boundaries is a key step for obtaining other biological information for the appropriate fisheries management. On this master thesis, the validity of one traditional character –ossicles morphometry- and molecular characters –DNA barcoding of two mitochondrial genes- have been tested for the right taxonomic identification of H. sanctori, H. mammata, H. tubulosa, H. arguinensis and H. polii. Also, the possible variation of these characters in relation to the geographical range of species was considered. Our results suggest that the ossicles are useful character to discriminate H. santori, H. polii and H. tubulosa, but they are not for H. arguinensis and H. mammata. These last two species showed high rates of intra-specific variability. Part of this variability could be linked to geographical factors, showing morphometric differences between the Atlantic and Mediterranean populations. Molecular barcoding from partial sequences of COI and 16S genes, distinguished five well supported clades. Genetic barcoding seems to be more effective for taxonomical identification of these target species than the morphological criteria. The information obtained from this Msc Thesis provides more accurate boundaries between species and practical tools for their identification, which will allow to develop more efficient fisheries management.
Os pepinos do mar o holoturias são invertebrados bentónicos exclusivamente marinhos incluidos no grupo dos Echinodermos. O grupo contém um total de 1400 espécies distrubuidas em 6 ordens. A familia Holothuroidea, incluída na ordem Aspidochirotida, é dividida em 5 géneros entre os quais, está incluido o género Holothuria. O género Holothuria inclui maioritariamente espécies de águas pouco profundas e algumas das espécies são distribuidas no Mediterraneo e no noreste do océano Atlantico. Os pepinos de mar realizan uma importante função ecológica no ciclo dos nutrientes e da materia orgânica, além de representar uma importante quantidade da biomasa de invertebrados no seu habitat. Nos últimos anos o pepino de mar tem sido o objetivo de uma intensa pesca, devido ao seu valor comercial na Asia. A forte demanda mudou a pesca para países onde eles não foram comsumidos tradicionalmente, entre os quais se incluem Portugal e Espanha. Apesar da importancia ecologica e económica das especies incluídas no género, a sua taxonomía mudou várias vezes no final do século XX e ainda esta em discussão. As dificultades da taxonomía no genero devem-se principalmente ao número limitado de caracteres morfológicos da taxonomía e a grande variabilidade intra-especifica dos caracteres. Um dos principais caracteres na taxonomía das Holoturia são os osiculos, uma estrutura de carbonato cálcico que se encontra na pele e outras partes do corpo nos pepinos do mar. Porém há varios autores que têm questionado a sua validade, devido a alterações significativas durante o crecimento dos individuos, e os possíveis efeitos das variáveis ambientais na morfología dos osiculos. Nesta tese de mestrado, nos vamos a avaliar a utilidade de alguns caracteres da taxonomía dos pepinos de mar: um carácter tradicional, os osiculos, e um carácter molecular, com o “barcoding” das sequências parcias de dois genes mitocôndriais o COI (Citocromo Oxidasa I) e o 16S (DNA ribosomal). Os objectivos são encontrar caracteres úteis para a correcta identificação das 5 espécies do género Holothuria com interesso comercial, H. arguinensis, H. mammata, H. tubulosa, H. polii and H. sanctori, e avaliar a sua variabilidade em relação com a distribuição geográfica Um total de 47 individuos foram recolhidos nas diferentes localidades que incluem os limites da distribuição das especies. A análise dos caracteres tradicionais foi realizado únicamente em dois tipos de osiculos, os botões e as mesas devido à sua maior importancia para a identificação das holoturias de acordo com as referências bibliográficas. Um total de 8 variáveis morfométricas nos botões e 11 variáveis nas mesas foram medidas. As variáveis morfométricas medidas nos dois tipos de osiculos foram a área, o perímetro, o perímetro convexo, o diámetro máximo, o diámetro mínimo, o número de buracos, a área total dos buracos e a área média dos buracos. Além disso, no caso das mesas, foram medidas mais 3 variáveis, a altura da mesas, a largura do disco das mesas e a largura da espiral das mesas. Finalmente a partir destas variáveis foram calculados 5 índices morfométricos para os botões e 6 para as mesas. O análise dos componentes principais determino que existe uma ordenação das espécies no espaço em relação às variáveis estudadas. O espaço principal foi determinado por 11 variáveis, sendo estas, área total dos buracos dos botões (TArHb), área média dos buracos dos botões (ArHb), área total dos buracos das mesas (TArHt) e a área média dos buracos das mesas (ArHt), o diámetro mínimo das mesas (NDt), a altura das mesas (HTLt), a largura da espiral das mesas (WSLt), a largura do disco das mesas (WDLt), o perímetro da mesa (Pt), o perímetro dos botões e o diámetro máximo dos botões . As variáveis selecionadas foram incluidas no analise lineal discrimiante. Os resultados determinaron que únicamente 3 das especies, H. sanctori, H. polii e H. tubulosa, podem ser diferenciadas de acordo com as variables medidas nos osiculos. Porém, a distribuição das espécies mostrou especialmente uma grande dispersão no espaço da análise dos componentes principais e uma grande variabilidade das variáveis dentro das espécies. Com o objetivo de explicar as causas da dispersão dos dados, as localidades da amostragem foram representadas no espaço dos componentes principais. A distribuição dos locais da amostragem mostrou a existência de quatro grupos, dos quais 3 foram formados apenas por localidades do Mediterrâneo e do Atlântico. Foi realizada uma nova análise com as duas espécies (Holothuria mammata e H. arguinensis) comuns na amostragem que se incluiam tanto na amostra Mediterrânea como na Atlântica. Os resultados mostraram uma diferenciação na morfometria dos osiculos entre os indivíduos recolhidos no Mediterrâneo e os recolhidos no Atlântico dentro da mesma espécie. Portanto, os nossos resultados sugerem que a morfometria dos osiculos pode ser afectada pelas diferenças ambientais entre o Atlântico e o Mediterrâneo. Os orifícios dos osiculos dos individuos recolhidos no Atlântico são maiores em relação aos individuos do Mediterrâneo. Um total de 19 sequências do 16S, 18 do COI e 12 da combinação das sequências do COI e 16S, foram analizadas mediante o método do vizinho mais próximo, mediante distâncias genéticas baseadas em Kimura dois-parâmetros. Os resultados em todas as analises mostraram a existência de 5 clados bem definidos pela distância genética. As maoires distancias genéticas foram encontradas entre H. sanctori e todas as espécies, seguido de H. polii. As distancias entre H. mammata, H. tubulosa e H. arguinensis mudo dependiodo na sequência analizada. A menor distancia no COI foi encontrada entre H. mammata e H. arguinensis, mais no 16S foi entre H. arguinensis e H. mammata. No entanto o COI parece ser mais eficiente na identificação das especies pela sua maior taxa de mutação. A identificaçao dos individuos mediante as técnicas moleculares coincidem com as identificaçõess previas mediante caracteres morfológicos, com a exceção, dum individuo previamente identificado como H. arguinesis, o qual foi agrupado junto os individuos da H. mammata em todas as sequêcias. O analise dos osiculos demostrou que uma possível explicação e, a existencia de um híbrido entre as duas especies, mais não foi possível demostrar este facto com os analise realizados nesta tese. Nossos resultados sugierem que os osiculos tem una capacidade limitada para a identificação das diferentes espécies, principalmene devido a sua grande variabilidade. Parte desta variabilidade podria estar relacionado com a distribução dos individuos e as diferentes características ambientais. As técnicas moleculares foram mais efectivas para a identificação das espécies, espcialmente as sequêcias obtenidas do COI. A comparação dos resultados morfológicos é genéticos sugerem a existencia de um híbrido entre as espécies H. arguinensis e H. mammata, mais é preciso futuras pesquisas científicas para comprovar esta possibilidade.