Current technology used to diagnose hearing disorders is limited. This is mostly due to the fact that the auditory structures are very small and not easily accessible with existing imaging technologies. The objective of this dissertation was to investigate the potential of high-frequency ultrasound as a tool for exploring the anatomy of the auditory system. Three studies were conducted in order to demonstrate the feasibility of high-frequency ultrasound as a diagnostic technology for hearing disorders. In the first study, an in-house developed 50 MHz annular array-based ultrasound system was used to provide ex-vivo images of auditory structures in cadaveric temporal bones. It was shown that the spatial resolution was sufficient to visualize a high level of detail of the ossicular bones of the middle ear as well as intra-cochlear structures of the inner ear. In the second study, a 50 MHz 1.26? pitch phased array ultrasound transducer was designed for imaging intra-cochlear structures through the round window membrane. As this element pitch results in large grating lobe artifacts, novel transmit beamforming techniques were developed to suppress grating lobes resulting from this large-pitch array. Theoretical techniques using the impulse-response simulation method and experimental verification using high-frequency linear array ultrasound system (Vevo 2100, VisualSonics, Canada) showed that these techniques were able to suppress grating lobe levels up to 40 dB. In the third study, a needle mounted 45 MHz single-element ultrasound probe was fabricated in order to measure the vibrations of intra-cochlear structures on human cadavers. Basilar membrane velocimetry measurements were successfully performed using pulsed-wave Doppler ultrasound in the frequency range between 100 Hz-2 KHz. The measured velocity of the basilar membrane and the round window membrane showed that the middle ear resonance frequency near 1 KHz was present over multiple temporal bones. This is the first work that has explored the human auditory system with high resolution ultrasonic visualization and Doppler velocimetry.

Le complexe des lobes terminaux du système turbiditique du Congo, localisé à 760 km des côtes de l’Afrique Equatoriale et à 5000 m de profondeur, constitue un système sédimentaire unique pour étudier les transferts de matière organique dans l’Océan Atlantique. En effet, ce complexe, d’une superficie de 3000 km² environ, est actuellement le réceptacle final des apports turbiditiques, initiés dans le canyon du fleuve Congo. Cette thèse, qui s’inscrit dans le cadre du projet ANR-Congolobe, a pour objectif d’apporter des connaissances sur la composition biogéochimique de ces apports et d’apporter des conclusions sur leur(s) origine(s), leur distribution et leur devenir dans les sédiments. Pour ce faire, neuf carottes d’interface (~20 cm) et une carotte longue (~900 cm) prélevées en différents sites du complexe des lobes ont été étudiées. La stratégie employée a consisté (1) à réaliser une description des faciès et de la granulométrie des sédiments, (2) à réaliser une étude géochimique globale et moléculaire sur ces mêmes sédiments (%Corg, C/N, δ13Corg et δ15N, 137Cs, acides gras, tétraéthers) (3) à confronter les données acquises avec celles obtenues sur les sources initiales marines et terrestres par un modèle de mélange binaire (δ13Corg) et par une analyse discriminante (acides gras), (4) à considérer un site spécifique en tant que référence temporelle, (5) à combiner les données acquises à tous les sites dans une analyse multivariée pour appréhender le devenir de cette région à l’échelle millénaire. Tous les marqueurs considérés ont révélé que les sédiments des lobes constituent un véritable puits de matière organique particulaire terrigène en provenance du Congo. Les concentrations en carbone organique sont élevées dans les sédiments argilo-silteux (~3 à 5 %). 70 à 80 % de ce carbone organique dérive du fleuve et consiste en des débris végétaux et en de la matière organique altérée issue de l’érosion des sols, alors que les 20 à 30 % restants consistent en une matière organique marine très dégradée. Une analyse plus détaillée des biomarqueurs lipidiques suggère que la matière organique apportée par les turbidites est peu réactive, néanmoins, l’analyse des acides gras a permis de détecter la présence de composés marins frais dans certains échantillons. Une conclusion importante de cette étude est que tous les résultats portant sur la composition et la distribution de la matière organique dans les sédiments sont en accord avec les modalités de dépôt turbiditique (rapidité du transfert, fréquence des apports, épaisseur des dépôts) ainsi qu’avec les propriétés granulométriques des sédiments. Ces caractéristiques physiques permettent d’expliquer que la matière organique soit exceptionnellement bien préservée dans les couches anoxiques des sédiments, une observation valable à l’échelle des millénaires qui soulève l’intérêt de prendre en compte la région des lobes pour comprendre le devenir de la matière organique terrestre dans l’océan global. / The terminal lobe complex of the Congo deep-sea fan, which is a unique region to study the transfer of organic matter from the land to the Atlantic Ocean, is located 760 km off the Equatorial African coast and at 5,000 m depth. This region covers 3000 km2 and is the terminal receptacle of the particulate organic matter provided by turbidity currents originating from the Congo River canyon. This thesis is part of the Congolobe ANR-project and aims at providing information on the biogeochemical composition of these organic matter inputs to study their origin, distribution and fate in lobe complex sediments. Nine short sediment cores (~20 cm) and one long core (~900 cm) were collected in different sites of the lobes complex for different sediment analyses. The strategy of the study consists of the following five analytical steps: (1) to achieve a facies and granulometry description of the sediments; (2) to study the global and molecular geochemical characteristics of the sediments (%OC , C/N, δ13Corg, δ15N, 137Cs, fatty acids and tetraethers); (3) to compare these data to data from marine and terrestrial end-members using a binary mixing model (δ13Corg) and a discriminant analysis (fatty acids); (4) to consider a specific site as a time reference and (5) to discuss the fate of the sedimentary organic matter at the millennium time scale of the overall area by combining different data in a multivariate analysis. All the different proxies used in this study revealed that lobe sediments could be a sink for organic inputs from the Congo River. Organic carbon concentrations are high in silty-clay sediments (~3 to 5 %). Over the study region, 70 to 80 % of the organic carbon originate from the Congo River and consist of vegetal detritus and soil derived-OM. The remaining 20 to 30 % consists of highly degraded organic matter. A more detailed lipid biomarker analysis shows that the organic matter is poorly reactive; however, fatty acid analyses reveal the presence of fresh planktonic compounds in some samples. An important finding of this study is that the composition and the distribution of the organic matter in sediments are consistent with turbiditic deposition patterns (e.g., rapidity of transfer, frequency and thickness of deposits) as well as with the granulometry properties of the sediments from the terminal lobe complex. Due to the specific sediment characteristics, organic matter is exceptionally well preserved in the anoxic sediment layers, reaching back to millennial time scales. Hence, studying the lobe complex area is of great interest for a better understanding of the fate of terrestrial organic matter in the global ocean.

Nondestructive evaluation techniques were employed to fully characterize three 2.3L camshafts tested in an engine simulator for an equivalent of 100,000 miles. Optical microscopy, acoustic microscopy (SAM), and profilometry were used to characterize wear and fatigue, crack depth, and surface roughness, respectively. Results show cracking to occur mainly in the opening ramp of the most abusively ground cam lobes. No clear evidence was found for subsurface cracking at depths as great as 200 μm from the lobe's surface. Profilometry results show no evidence of any major tribological effect due to the sliding friction of the follower. Fractography studies show a difference between fracture surfaces among the cracks examined; straight cracks exhibit features resembling fatigue propagation, while fracture surfaces from pitted cracks show a more brittle behavior. Small grinding cracks (approximately 300 μm in length) were found in the opening ramps of the most abusively ground lobes prior to testing. Knoop and Nanoindenter microhardness indicate a near-surface rehardening for the most abusively ground lobe (confirmed by metallography), and temper burn for the remaining lobes. X-ray residual stress results made in the opening ramp of the tested lobes show evidence of residual stress relaxation. X-ray line width data as a function of depth does not correlate with residual stress. / Master of Science

In real-world settings, decision-making typically resembles a stepwise process in which one decides which information to sample before deciding to which decision option to commit. The former step is called instrumental information-seeking, and theoretical and empirical findings indicate that it is mediated by the value of information (VOI), the extent to which obtaining information increases the expected value of future actions and decisions. Economic theory predicts that to estimate VOI, decision-makers conduct a preposterior analysis in which they prospect what they would expect to know about the decision options after observing the information—or, in terms of Bayesian inference, they should prospect the future posterior probabilities. But the neural mechanisms underlying this early step of the computation of VOI remain an open question. Therefore, to further investigate the neural substrates of instrumental information-seeking, we used functional magnetic resonance imaging (fMRI) in conjunction with two interrelated behavioral tasks in humans. With one task, we examined the demand for instrumental information, but since preposterior analysis relies on the prospection of potential future posterior beliefs, we included another task to examine how people form posterior beliefs after receiving information. We found that regions of posterior parietal cortex and occipital fusiform gyrus appear to support a preposterior analysis through the prospection of expected posterior certainty. This aligned with our finding of a region of parieto-occipital cortex that appears to support Bayesian inference by integrating the prior probability of a hypothesis with the likelihood of observed information. These results imply that parietal cortex plays a key role in Bayesian inference, supporting preposterior analysis during information-seeking in addition to Bayesian inference during categorical decision-making.

Submitted by Marlucy Farias Medeiros (marlucy.farias@unipampa.edu.br) on 2018-05-11T18:52:52Z No. of bitstreams: 1 Daniel_Lemes - 2018.pdf: 18189235 bytes, checksum: 1ee5df4451f15272b5fcd3e07ef614e8 (MD5) / Approved for entry into archive by Dayse Pestana (dayse.pestana@unipampa.edu.br) on 2018-05-14T12:00:34Z (GMT) No. of bitstreams: 1 Daniel_Lemes - 2018.pdf: 18189235 bytes, checksum: 1ee5df4451f15272b5fcd3e07ef614e8 (MD5) / Made available in DSpace on 2018-05-14T12:00:34Z (GMT). No. of bitstreams: 1 Daniel_Lemes - 2018.pdf: 18189235 bytes, checksum: 1ee5df4451f15272b5fcd3e07ef614e8 (MD5) Previous issue date: 2018-04-05 / The main goal of this work was to develop a MATLAB-based co de capable of finding the optimum values for amplitudes, phases and spacings of a non-uniformly spaced linear antenna array for a specified purpose. This tool allowed investigating the influence of the relative spacings between the elements of an antenna array in its radiation pattern. Two optimization methods were implemented: PSO (Particle swarm optimization), which is an evolutionary heuristic based on the social interaction and movement of swarms, and Taguchi’s method, which is based on orthogonal arrays to reduce the number of experiments needed to find the optimum value of a given variable. Different optimization goals were investigated, so that a comparison between these techniques has been done. The developed co de was applied to solve two practical problems. In the first one, a dual-band antenna array for base stations of mobile communication systems was modeled and its amplitudes, phases and spacings were optimized. By doing so, it was possible to mitigate the granting lobes that app eared in the pattern in the higher band, because the relative spacings between the elements could not be smaller than λ0. The pattern of this array was also shaped following a squared cosecant contour, in order to illuminate a pico-cell with uniform power. The results of the optimizations in both bands were validated using the commercial software Ansys HFSS and a study about the influence of the mutual coupling in the pattern was done. The second practical problem was to design an antenna array with beamshaping. By using the proposed code, it was possible to reduce the number of array elements from seven to four comparing to an uniformly spaced array. The optimization was split into two parts in order to mitigate the influence of the mutual coupling. A passive feeder for the optimized array was designed and a prototype was manufactured. The results were validated using HFSS and by measurements. The complete development of the array and of the feeder are detailed in this work. Finally, the design of a transmitter for adaptive beamshaping is described. The architecture nis capable to change the phase and power level of the signal, hence allowing to deliver the weights optimized by the proposed code to the antenna array. A modular concept was chosen in order to increase the flexibility of the transmitter. The device translates the input frequency from 500 MHz to 7 GHz, in order to deliver the weights to the antenna array. Eight transmitters were assembled and they were coupled to the antenna array in order to test their functionality. The patterns were measured in an anechoic chamber. All measured results of the transmitter are presented. / O principal objetivo deste trabalho foi desenvolver uma ferramenta computacional em MATLAB capaz de otimizar as fases, as amplitudes e os espaçamentos de uma rede de antenas, a fim de satisfazer um determinado objetivo. De posse dessa ferramenta, foi possível analisar a influência do espaçamento relativo entre os elementos de uma rede no diagrama da mesma. Dois métodos de otimização foram implementados: PSO (Particle Swarm Opmitization), baseado na interação social e no movimento de um enxame, e o método de Taguchi, que utiliza matrizes ortogonais para diminuir o número de testes necessários para otimizar uma variável. Diferentes cenários foram analisados de forma a permitir uma comparação entre os dois métodos. O código desenvolvido foi aplicado a dois problemas práticos. No primeiro deles, uma rede de antenas dupla-faixa para emprego em estações rádio base de sistemas de comunicações móveis foi modelada e suas amplitudes, fases e espaçamentos foram otimizados. Como na banda mais alta o espaçamento entre os elementos não podia ser menor que λ0., fez-se necessário otimizar os espaçamentos para controle dos grating lobes. O diagrama dessa rede foi também conformado seguindo um contorno em cossecante ao quadrado, para iluminar uma certa região com potência uniforme. Os resultados de todas as otimizações em ambas bandas foram validados usando o software Ansys HFSS e um estudo sobre a influência do acoplamento mútuo foi feito. O segundo caso consistiu na otimização de uma rede de antenas com conformação de feixe. Foi possível diminuir o número de elementos de sete para quatro em comparação a uma rede com elementos uniformemente espaçados. A otimização foi dividida em duas partes para compensar o efeito do acoplamento mútuo. Para a rede otimizada, um sistema alimentador passivo foi desenvolvido e um protótipo foi fabricado. Os resultados foram validados com simulações no software comercial Ansys HFSS e, também, por medições. Todo o projeto da rede e do alimentador é detalhado neste trabalho. Finalmente, o desenvolvimento de um circuito transmissor para beamshaping adaptativo ´e detalhado. Tal sistema é composto por um defasador e um amplificador de ganho variável, com os quais é possível inserir as amplitudes e fases, otimizadas pelo código proposto, em uma rede de antenas. Desenvolveu-se um transmissor modular, a fim de aumentar a flexibilidade do sistema. A frequência de entrada do transmissor é de 500 MHz, que é transladada para 7 GHz antes de ser entregue à rede de antenas. Foram fabricados oito transmissores, os quais foram acoplados a uma rede de antenas para testar suas funcionalidades. Os diagramas de irradiação foram medidos em câmera anecóica. Todo o desenvolvimento e medições de cada componente do transmissor são também mostrados neste trabalho.

Les travaux présentés dans cette thèse s'inscrivent dans le contexte des vibrations d'usinage et plus spécialement des parois minces, typiques des pièces de structure aéronautique. L'objectif est de contribuer à la maîtrise des phénomènes vibratoires à la fois au niveau théorique et pratique.<br />Nous avons identifié plusieurs voies de recherche visant : l'extension des méthodes classiques utilisant les « lobes de stabilité », la modélisation des phénomènes transitoires intervenant pendant une même passe d'usinage et enfin l'utilisation de la variation continue de la vitesse de rotation de l'outil.<br />La généralisation du tracé des lobes de stabilité sur une pièce à paroi fine, avec un comportement vibratoire très riche, impose l'ajout d'une troisième dimension permettant de prendre en compte les évolutions des paramètres au cours de l'usinage. Cette démarche permet l'amélioration notable d'une opération d'usinage. Cependant, certaines phases sont impossibles à optimiser et présentent un comportement très complexe, difficile à modéliser en pratique. La troisième partie porte sur le développement d'un modèle numérique relativement simple, permettant de prendre en compte tous les aspects, jugés indispensables à la modélisation de parois minces. L'utilisation de ce modèle temporel permet notamment d'interpréter les états de surface évolutifs, très souvent observés sur les passes d'usinage, mais rarement expliqués dans le détail, à notre connaissance.<br />La dernière partie présente l'étude et la mise au point d'une solution de réduction des vibrations régénératives, par une variation continue de la vitesse de rotation de la broche. Cette méthode apporte des gains importants en usinage grande vitesse, notamment dans la zone du « flip lobe ». Cependant, elle peut faire apparaître des vibrations transitoires, à l'échelle de la période de variation, qui réduisent son efficacité.

Ausgehend von den primärsensorischen Arealen verlaufen Verarbeitungswege nach anterior durch die Temporallappen, die der Objekterkennung dienen. Besonders die vorderste Spitze der Temporallappen, der anteriore Temporalkortex, wird mit Funktionen der Objektidentifizierung assoziiert. Es existieren jedoch mehrere Vermutungen, welcher Art die Objekte sind, die in dieser Region verarbeitet werden. Es gibt Annahmen über die Verarbeitung von Sprache, von menschlichen Stimmen, semantischen Informationen oder individuellen Konzepten. Um zwischen diesen Theorien zu differenzieren, wurden vier ereigniskorrelierte fMRT-Messungen an jungen gesunden Erwachsenen durchgeführt. Die Probanden hörten in drei Experimenten die Stimmen berühmter und unbekannter Personen und in einem der Experimente zusätzlich Geräusche von Tieren und Musikinstrumenten. Im vierten Experiment wurden Zeichnungen von Comicfiguren gezeigt sowie von Tieren und Obst- und Gemüsesorten. Die neuronale Aktivität bei der Verarbeitung dieser Reize im Vergleich zu Zeiten ohne Stimulation wurde mit Hilfe von Interesseregionen untersucht, die nahezu die gesamten Temporallappen abdeckten und diese in jeweils zwölf Areale untergliederten. In den anterioren Temporallappen waren sowohl mit auditiven als auch mit visuellen Stimuli deutliche Aktivierungsunterschiede in Abhängigkeit von der semantischen Kategorie festzustellen. Individuelle Konzepte (menschliche Stimmen und Zeichentrickfiguren) riefen eine signifikant stärkere Aktivierung hervor als kategoriale Konzepte (Tiere, Musikinstrumente, Obst- und Gemüse). Außerdem war das Signal, dass durch die Stimmen der bekannten Personen ausgelöst wurde, deutlich stärker als das Signal der unbekannten Stimmen. Damit sind die Daten am ehesten kompatibel mit der Annahme, dass die anterioren Temporallappen, bekannte individuelle Konzepte verarbeiten. Da die beschriebenen Signalunterschiede zwischen den verschiedenen Bedingungen ausgehend von den transversalen Temporalgyri nach anterior zum Temporalpol zunahmen, unterstützen die Ergebnisse zudem die Theorie von einem ventralen Verarbeitungsweg, der die Temporallappen nach anterior durchquert und zur Objekterkennung beiträgt. In Übereinstimmung mit den Annahmen der Konvergenzzonentheorie von A. R. Damasio scheint die spezifische Funktion dieses rostral gerichteten Verarbeitungsweges aus der sukzessiven Kombination immer mehr sensomotorischer Merkmale von Objekten zu bestehen. Da bekannte individuelle Konzepte eine besonders hohe Anzahl von Merkmalen aufweisen, ist eine weiter nach anterior verlaufende Verarbeitung zu beobachten als bei unbekannten oder kategorialen Konzepten. / It is assumed that neural pathways run from the primary sensory cortices through the temporal lobes towards their poles crossing areas necessary for object recognition. Especially the most anterior temporal parts were associated with processes contributing to the identification of objects. Yet, there is little agreement on the kinds of objects that are interpreted by the anterior temporal lobes. For example, there are assumptions regarding linguistic processing, voice recognition, the processing of general semantic information or the identification of unique entities. In order to differentiate between those theories, four event-related fMRI experiments were performed in healthy young adults. In three experiments, the subjects heard the voices of famous and unknown persons. In addition, characteristic sounds of animals and musical instruments were presented in one of these experiments. During the fourth experiment, drawings of famous cartoon characters were shown together with animals and fruit & vegetables. The neural activity in response to these stimuli compared to rest was analyzed using a regions-of-interest approach. 12 regions-of-interest that covered the majority of the temporal lobes were defined in each hemisphere. Both with auditory and visual stimuli, there were clear activation differences between the semantic categories in the anterior temporal lobes. Unique entities (human voices and cartoon characters) evoked a significantly stronger signal than categorical concepts (animals, musical instruments, fruit & vegetables). Furthermore, the signal in response to voices of familiar persons was significantly higher than to unfamiliar voices. Thus, the results are most compatible with the assumption that the anterior temporal lobes process supramodal features of familiar unique entities. As the before-mentioned signal differences between unique and categorical concepts and between familiar and unfamiliar voices increased from the transversal temporal gyri towards the temporal poles, the results support the notion of a ventral processing pathway running rostrally through the temporal lobes. In accordance with the convergence zone theory described by A.R. Damasio, the precise function of that pathway seems to consist in the incremental combination of sensorimotor concept features. Since familiar unique entities possess an especially high number of features, their processing was found to be directed into more anterior portions of the temporal lobe than the perception of unfamiliar or categorical concepts.

The contemporary terrestrial atmosphere loses matter at a rate of around 100,000 tons per year. A major fraction of the net mass loss is constituted by ions, mainly H+ and O+, which escape from the Earth’s ionosphere in the polar regions. Previously, the outflow has only been measured at low altitudes, but to understand what fraction actually escapes and does not return, the measurements should be conducted far from the Earth. However, at large geocentric distances the outflowing ions are difficult to detect with conventional ion instruments on spacecraft, since the spacecraft electrostatic potential normally exceeds the equivalent energy of the ions. This also means that little is known about the ion outflow properties and distribution in space far from the Earth. In this thesis, we present a new method to measure the outflowing low-energy ions in those regions where they previously have been invisible. The method is based on the detection by electric field instruments of the large wake created behind a spacecraft in a flowing, low-energy plasma. Since ions with low energy will create a larger wake, the method is more sensitive to light ions, and our measured outflow is essentially the proton outflow. Applying this new method on data from the Cluster spacecraft, we have been able to make an extensive statistical study of ion outflows from 5 to 19 Earth radii in the magnetotail lobes. We show that cold proton outflows dominate in these large regions of the magnetosphere in both flux and density. Our outflow values of low-energy protons are close to those measured at low altitudes, which confirms that the ionospheric outflows continue far back in the tail and contribute significantly to the magnetospheric content. We also conclude that most of the ions are escaping and not returning, which improves previous estimates of the global outflow. The total loss of protons due to high-latitude escape is found to be on the order of 1026 protons/s.

Le concept de radar passif aéroporté repose sur l'utilisation de plusieurs antennes réseau, disposées sur une plateforme en vue de couvrir un angle solide large de détection, en s'appuyant sur l'utilisation de signaux d'opportunité provenant d'émetteurs au sol. La détection aéroportée à partir de signaux d'opportunité est intéressante, notamment pour assurer l'autoprotection d'un avion ou d'un hélicoptère ; en revanche elle constitue un défi technique notamment en raison du niveau des signaux interférents, en provenance de l'émetteur et des trajets multiples indirects (le fouillis), bien supérieur au niveau de signal utile diffusé par la cible à détecter. D'autres effets, tels que la structure arbitraire des signaux (forme d'onde non-radar) et sa conséquence sur les lobes secondaires en distance, contribuent à la complexité du traitement à mettre en œuvre.Le point de départ des recherches se situe à l'intersection des techniques de radar passif (utilisant la corrélation entre un signal de référence non connu a priori et les signaux diffus renvoyés par l'environnement) et les techniques de type STAP (Space Time Adaptive Processing) utilisées pour la détection des cibles mobiles par les radars aéroportés conventionnels. Dans ce contexte, les travaux de thèse permettent d'étendre d'une part la caractérisation et la qualification des signaux " radar passif " à une configuration aéroportée, d'autre part les techniques STAP à une configuration bistatique et à des signaux de forme arbitraire et non structurés comme des signaux radar. Les recherches mettent en évidence l'importance primordiale du trajet direct et des premiers échos de fouillis qui parasitent la caractérisation spatio-temporelle des échos reçus dans la case distance de la cible sous test. La caractéristique du fouillis, habituellement tracée dans le plan Doppler-angle, se trouve affectée par ces interférences qu'il faut éliminer au préalable. Pour cela, un premier filtre à réponse finie est mis en œuvre sur chaque capteur, puis le traitement STAP est appliqué à l'ensemble du réseau d'antennes.Les traitements proposés sont simulés et les performances en détection sont analysées. Une expérimentation est conduite, à l'aide d'un réseau de 4 antennes mobiles au sol. Les conditions sont réunies pour collecter des signaux de fouillis étalés en Doppler et analyser l'effet d'une forme d'onde non-radar. Les traitements d'élimination des interférences sont mis en œuvre et ainsi qualifiés expérimentalement.

Made available in DSpace on 2014-06-11T19:26:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-29Bitstream added on 2014-06-13T20:14:37Z : No. of bitstreams: 1 pereira_llv_me_sjrp.pdf: 1182871 bytes, checksum: 6053df49fe569dc60c6513fafdffaa9d (MD5) / No presente trabalho verificamos que os testículos possuem morfologias diferentes podendo ser arredondados, arredondados/espiralados ou alongados/espiralados. Com relação à morfometria das células em prófase I, B. micantulum e R. zela foram as que apresentaram as menores células, G. f. flavus foi a que apresentou maior tamanho e R. c. crassifemur e M. brasiliensis apresentaram tamanho intermediário. A avaliação da espermatogênese nos permitiu concluir que as características observadas são semelhantes às das outras espécies de Heteroptera, descritas na literatura, diferindo apenas com relação à morfologia dos testículos, o número de cromossomos e o sistema cromossômico do sexo. A análise das ultraestruturas observadas durante a espermatogênese de Gelastocoris flavus flavus e Martarega uruguayensis mostraram a presença de várias mitocôndrias pequenas e uniformemente distribuidas pelo citoplasma em células em profase I, de ambas espécies, que foram se unindo formando o complexo mitocondrial, que possui no seu interior as mitocôndrias enoveladas, posteriormente este complexo mitocondrial se divide em duas estruturas denominadas derivados mitocondriais, que se dispõem bilateralmente ao axonema. O axonema dessas espécies possui o padrão de 9+9+2. A formação do acrossomo inicia-se nos primeiros estágios da espermiogênese sendo composto de muitas vesículas acrossomais que se unem formando uma única estrutura, sendo observada regiões e algumas estruturas mais coradas em seu interior. Basicamente o processo de espermiogênese não diferiu entre as duas espécies analisadas / In this study, we found different morphologies for testes of the Heteroptera species Belostoma anurum, B. micantulum, Gelastocoris angulatus, G. flavus flavus, Rheumatobates crassifemur crassifemur, Buenoa amnigenus, B. unguis, Martarega brasiliensis, M. membranacea, M. uruguayensis, Rhagovelia tenuipes and R. zela. They can by round, round/spiral and elongated/spiral. The size of prophase I cells also varied, being the smallest ones detected in B. micantulum and R. zela, the largest in G. f. flavus, and the intermediate in R. c. crassifemur and M. brasiliensis. The analyses of spermatogenesis allowed us to conclude that, in the studied species, the features are similar to those of other previously described Heteroptera species, differing only as to the testicular morphology, the chromosome number, and the sex chromosome system. Ultrastructural analysis of the spermatogenesis showed several small mitochondrias evenly distributed throughout the cytoplasm, in cells at prophase I of G. f. flavus and M. uruguayensis. The small mitochondrias joined to form the mitochondrial complex. Later, this mitochondrial complex divided into two structures called mitochondrial derivatives, located bilaterally to the axoneme. The axoneme of these species showed the flagellar pattern 9+9+2. The acrosome started to be formed in the early stages of spermiogenesis, being composed of many acrosome vesicles that join to form a single structure. Some regions within this structure were more strongly stained. Basically the process of spermiogenesis did not differ between the species G. f. flavus and M. uruguayensis