Com o objetivo de obter informações básicas sobre a bioecologia e o comportamento de Sphenophorus levis Vaurie, foram realizados diferentes bioensaios para conhecer seu comportamento sexual e reprodutivo; obter e testar a atividade biológica de seu feromônio natural em condições de laboratório e campo; verificar a eficiência de captura do feromônio sintético de agregação em condições de campo; determinar o tipo de armadilha mais eficiente para a captura e manejo de adultos; e avaliar o raio de ação das atuais armadilhas. Os resultados mostraram que S. levis, acasala-se em qualquer hora do dia, tem múltiplas cópulas, e os casais entre 14 e 35 dias de idade apresentaram as maiores frequências de cópulas, com 76 a 88%, respectivamente. A duração média da primeira cópula foi de 5,75 ± 4,22 h, e o tempo total de cópula variou entre 1 a 17 h. O período de pré-oviposição em fêmeas entre 14 e 35 dias, foi de 5,52 ± 4,53 a 10,90 ± 5,37 dias. O número de ovos/fêmea foi de 0,25 a 7,80, com viabilidade entre 33 e 63%. Fêmeas de S. levis com idade avançada entre 85 e 210 foram receptivas ao acasalamento (66%), ovipositaram entre 4,50 a 7,09 ovos, com viabilidade entre 49 e 79%. Machos e fêmeas de S. levis aptos ao acasalamento, apresentaram uma sequência típica de comportamentos para efetivar a cópula. A duração da pré-cópula variou de 2 a 5 horas. A cópula foi longa, com uma duração entre 7 a 13 horas. A pós-cópula durou entre 1,31 a 1,41 horas. O comportamento sexual associado à cópula foi influenciado pelo contato visual entre os casais e físico com outros indivíduos da espécie. Bioensaios em olfatômetro Y demonstraram que os machos foram estimulados por voláteis de cana; cana + machos; e cana + fêmeas; enquanto as fêmeas apenas por cana + machos. Os machos responderam ao extrato natural de macho + cana; as fêmeas ao extrato de machos + cana, extrato de fêmeas e extrato de fêmeas + cana. O isômero (S)-2-metil-4-octanol gerou atividade comportamental de ambos os sexos de S. levis. No campo, a avaliação da atratividade dos extratos naturais e os compostos sintéticos (isômeros S; R e mistura racêmica S-R), mostraram diferença na captura de fêmeas e totais de adultos de S. levis entre o isômero R e o controle; no entanto, não diferiram dos demais tratamentos. A captura de adultos selvagens de S. levis nas diferentes armadilhas testadas, diferiu entre o controle (isca CTC) e as armadilhas testadas (modelos galão, funil, e moleque da bananeira). A recaptura de adultos marcados de S. levis foi baixa e correspondeu a apenas 2% dos insetos liberados, sendo maior a distância de 5 m (10 adultos). De forma geral, estes resultados contribuem para o conhecimento do comportamento sexual e reprodutivo de S. levis e são úteis para futuros programas de manejo integrado desta praga. / With the aim of obtaining basic information on bioecology and behavior of Sphenophorus levis Vaurie, different bioassays were realized in order to understand its sexual and reproductive behavior; obtain and test the biological activity of its natural pheromone under laboratory and field conditions; verify the capture efficiency of the synthetic aggregation pheromone under field conditions; determine the most efficient type of traps for capture and management of the adults; and evaluate the radius of action of the current traps. The results showed that S. levis mates any time of the day, has multiple mating and the mates between the ages of 14 and 35 days presented the highest mating frequencies of 76 to 88%, respectively. The mean duration for the first mating was 5.75 ± 4.22 h, and the total mating time varied between 1 to 17 h. The pre-oviposition period for females between 14 and 35 days, was 5.52 ± 4.53 to 10.90 ± 5.37 days. The number of eggs/female was 0.25 to 7.80, with viability of between 33 and 63%. Females of S. levis with advanced age between 85 and 210 days were receptive to mating (66%), oviposited between 4.50 to 7.09 eggs with viability between 49 and 79%. Males and females of S. levis with capacity to mate presented typical frequency behavior to effect mating. The pre-mating duration varied from 2 to 5 hours. Mating was long with duration of 7 to 13 hours. The post-mating duration lasted between 1.31 to 1.41 hours. Sexual behavior associated with mating was influenced by visual contact between the couples and the physical among coespecifics. Bioassays in a Y tube olfatometer demonstrated that the males were responsive to sugarcane volatiles; sugarcane + males; and sugarcane + females; while the females were stimulated at least by sugarcane + males. The males responded to the natural extract of male + sugarcane; while the females to the extract of males + sugarcane, extract of females and extract of females + sugarcane. The isomer (S)-2- methil-4-octanol generated behavioral activity of both sexes of S. levis. In the field, the evaluation of attractivity of natural extracts and the synthetic compounds (isomer S; R and racemic mixture of S-R), showed differences in the capture of females and totals of adults of S. levis between the isomer R and the control; however, it was not different in other treatments. The capture of wild S. levis adults in the different tested traps differed between the control (bait CTC) and the tested baits/traps (models galão, funil, and moleque da bananeira). The recapture of marked adults of S. levis was low and corresponded to 2% of the liberated insects within the longest distance of 5 m (10 adults). In general, these results add to the knowledgment of S. levis sexual and reproductive behavior and are useful to future programs of integrated management of this pest.

Neste estudo, foi testada a atratividade de novos semioquímicos a fêmeas da broca-do-café, Hypothenemus hampei (Ferrari), que é a principal praga da cultura do café no mundo. Armadilhas iscadas com Trat. 1, Trat. 2 e Trat. 3 foram testadas em combinação ou não com etanol e metanol \'E:M\' (mistura 1:1) em uma área de cafezal localizada em Inconfidentes-MG, Brasil. O resultado mais importante foi que armadilhas iscadas com Trat. 1 + E:M atraíram significantemente mais adultos da broca-do-café do que os outros tratamentos isolados ou combinados. Por outro lado, armadilhas iscadas com compostos voláteis de frutos de café Trat. 2 + E:M não diferiram de E:M. Já armadilhas iscadas com Trat. 3 + E:M atraíram menos besouros do que E:M. Um número significativo de outras espécies de Scolytinae também foram atraídos por armadilhas iscadas com Trat. 1 + E:M e E:M. Além disso, um número muito baixo de outros insetos de, pelo menos, oito ordens também foram atraídos por estes dois tratamentos. Tomados juntos, estes resultados oferecem evidências convincentes de que Trat. 1 e E:M são sinérgicos para a captura de H. hampei, favorecendo o desenvolvimento de uma nova estratégia para o manejo integrado desta espécie em cafezais. / In this study, it was tested the attractiveness of new semiochemicals to coffee berry borer females, Hypothenemus hampei (Ferrari), that is the most important pest of coffee in the world. Traps baited with Treat. 1, Treat. 2 and Treat. 3 were tested in combination or not with ethanol and methanol \"E:M\" (1:1 mixture) in a coffee growing area located in Inconfidentes, MG, Brazil. The most relevant result is that traps baited with Treat. 1 + E:M attracted significantly more coffee berry borer adults than the other treatments. On the other hand, traps baited with coffee fruits volatile compounds Treat. 2 + E:M were similar to the ones bated with E:M. Yet traps with Treat. 3 + E:M attracted significantly less beetles than traps with E:M. A significant number of other Scolytinae species were also attracted by Treat. 1 + E:M and E:M. Moreover, a very low number of other insects from, at least, eight orders were also attracted by these two treatments. Taken together, these results offer compelling evidences that Treat. 1 and E:M are synergistic for the capture of H. hampei, promoting the development of a new strategy for the integrated management of this species in coffee growers.

Made available in DSpace on 2016-01-26T12:51:51Z (GMT). No. of bitstreams: 1 angelitabarbosa_dissert.pdf: 1284734 bytes, checksum: 9ee3bba6bd44f03d69e3b378a64a84fa (MD5) Previous issue date: 2006-03-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Oviposition traps are considered important entomological surveillance tools for Aedes aegypti, although they are still not used in routine activities of the Dengue Control Program in Brazil. The aims of this study were to evaluate the behavior of oviposition traps and related them to larval density measures and climatic data. This study was performed in a quarter from São José do Rio Preto, state of São Paulo, where fifty blocks were selected and two houses in opposite sides of each block were chosen to have the traps installed. A trap was installed at unshaded outdoor sites in each house, next to plants and in a height ranging from 0,5m to 1m. A measure was made each fifteen days, from October 2003 to September 2004, with the installation of the oviposition traps in the first week and the removal of them at the second week. Larval density measures were performed each fifteen days and climatic data was obtained on daily basis. The method of Generalized Estimation Equation was used to adjust the models among the positivity, the mean number of eggs and the other analyzed variables. Three distinct periods were identified at the positivity behavior of the oviposition traps and the mean number of obtained eggs. At the first (October to November), there was an increase in the values; at the second (January to May), the values remained stable; and at the third (June to September), there was a decrease. The observed values of positivity and the mean number of eggs observed at the first and third periods followed the variations in climatic data. From October to December, high correlations were obtained between the positivity and mean number of eggs, showing that one variable predicts the other and, at this period, the mean number of eggs can be estimated just by the positivity. The adjusted models for the positivity and mean number of eggs had temperature, humidity, pluviosity and fortnight as explicative variables. They also indicated the possibility of obtaining predictive models in a way these measures could be estimated without the necessity of fieldwork activities. For both models, the larval density measure was not included as an explicative variable. The trap presented a sensibility to detect Aedes aegypti higher than 90% and the larval density measures were always inferior to 25%. The periods from October to December and June to September were identified as the most appropriate to use oviposition traps as entomological surveillance tools. The period from December to June was identified as the ideal time to perform larval density measures. / Armadilhas de oviposição são consideradas importantes medidas de vigilância entomológica para Aedes aegypti, entretanto ainda não são utilizadas nas atividades de rotina no Programa de Controle da Dengue no Brasil. Este estudo teve como objetivos avaliar o comportamento das armadilhas de oviposição e relacioná-lo com as medidas de densidade larvária e climáticas. O trabalho foi realizado em um bairro da cidade de São José do Rio Preto, Estado de São Paulo, onde 50 quadras foram selecionadas e, em cada quadra, foram escolhidas duas casas em faces opostas. Em cada casa foi instalada uma armadilha no peridomicílio ao relento, próxima às plantas e a uma altura de 0,5m a 1m. Foram feitas medidas quinzenais, entre outubro/2003 a setembro/2004, com a colocação das armadilhas na primeira semana e retirada na segunda. Foram realizadas, quinzenalmente, medidas de densidade larvária e obtidos dados climáticos diários. Utilizou-se o método das Equações de Estimação Generalizadas para ajuste de modelos entre a positividade e o número médio de ovos e as demais variáveis analisadas. Foram identificados três períodos distintos no comportamento da positividade das armadilhas e no número médio de ovos encontrados. No primeiro (outubro a dezembro) ocorreu aumento dos valores, no segundo (janeiro a maio) os valores permaneceram em um patamar e no terceiro (junho a setembro) ocorreu decréscimo. Os valores da positividade e o número médio de ovos observados no primeiro e terceiro períodos acompanharam as variações observadas nos dados climáticos. Durante os meses de outubro a dezembro, altas correlações foram obtidas entre a positividade e número médio de ovos, mostrando que uma variável prediz a outra e que neste período o número médio de ovos pode ser estimado apenas pela positividade. Os modelos ajustados para a positividade e o número médio de ovos tiveram como variáveis explicativas temperaturas, umidades, pluviosidade e quinzena e indicaram a possibilidade da obtenção de modelos preditivos de modo que essas medidas poderiam ser estimadas sem a necessidade da realização de atividades de campo. Para ambos os modelos, a medida de densidade larvária não foi incluída como variável explicativa. A armadilha apresentou sensibilidade para a detecção de Aedes aegypti sempre superior a 90% e a medida de densidade larvária sempre inferior a 25%. Identificaram-se os períodos de outubro a dezembro e junho a setembro com os mais propícios para utilização das armadilhas de oviposição como medidas de vigilância entomológica e o período de dezembro a junho como ideal para a realização de medidas de densidade larvária.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-28T13:42:46Z No. of bitstreams: 1 2011 - Luciano Martins.pdf: 2085328 bytes, checksum: e82ea56c9ce66ac46b97ad748fb1de5a (MD5) / Made available in DSpace on 2016-07-28T13:42:46Z (GMT). No. of bitstreams: 1 2011 - Luciano Martins.pdf: 2085328 bytes, checksum: e82ea56c9ce66ac46b97ad748fb1de5a (MD5) Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aims to compare three sampling techniques to estimate species richness of ants (Hymenoptera: Formicidae) in ?campos of altitude? at Itatiaia National Park, in Rio de Janeiro state. Compared richness estimates for genera and species, and curves of accumulation of species for sardine baits, pitfall traps and manual collecting are presented for two distinct sites ("steppe vegetation" [VE] and "rupicola vegetation" [VR]) in Itatiaia Plateau. The three techniques collected 31 species of 10 genera belonging to four subfamilies. In VE were registered 50% of genera and 36.4% of species collected exclusively by baits, and 20% and 50% by pitfall traps, respectively. In VR were registered 37.5% of genera and 47.61% of species exclusive for baits, but no one genus and species was restricted for manual collecting. In the case of ?campos de altitude? and when only one technique can be used, the sardine bait was the most efficient sample technique to registered richness at VE. For VR, the manual collecting was the most appropriate technique to record species richness. However, the pitfalls (in VE) and bait (in VR) recorded an important portion of species richness. In our data, the manual collecting were associated with standardized data collecting protocols, and, although much criticized, have shown effectiveness in recording species in habitats where widespread techniques cannot be used. In spite of different physiognomies show differentiated efficiency for samples techniques, it is relevant to using more than one technique associated to a colleting protocol well structured to potentiated the record of the new species in environments as the ?campos de altitude?. / O presente trabalho tem por objetivo comparar tr?s t?cnicas de coleta para estimar a riqueza de esp?cies de formigas (Hymenoptera: Formicidae) no Planalto do Itatiaia , Rio de Janeiro, Brasil. S?o apresentados dados comparativos das estimativas da riqueza de g?neros, de esp?cies e as curvas de acumula??o de esp?cies amostradas com iscas de sardinha, armadilhas de queda e coletas manuais, em duas fisionomias distintas (?vegeta??o est?pica? [VE] e ?vegeta??o rup?cola? [VR]), no Planalto do Itatiaia. Com a utiliza??o das tr?s t?cnicas foram coletadas 30 esp?cies de 11 g?neros, pertencentes a quatro subfam?lias. Para a VE foram registrados 50% dos g?neros e 36,4% das esp?cies coletadas exclusivamente pelas iscas, e 20% e 50% pela armadilha de queda, respectivamente. Para a VR foram registrados 37,5% e 47,61% dos g?neros e esp?cies exclusivas para iscas, por?m nenhum g?nero e esp?cie foram restritos a coleta manual. Em se tratando de ecossistema de campos de altitude e quando apenas uma das t?cnicas possa ser utilizada, a isca de sardinha foi a mais eficiente para amostrar a riqueza em VE. Para VR, a coleta manual se apresentou como a t?cnica mais apropriada para registrar sua riqueza. No entanto, as armadilhas de queda (na VE) e as iscas (na VR) registraram uma parcela n?o t?o desprez?vel da riqueza. Em nossos dados, as coletas manuais foram associadas a protocolos de coleta padronizados, e, apesar de serem bastante criticadas, mostraram efici?ncia no registro de esp?cies em habitats em que outras t?cnicas mais difundidas n?o podem ser utilizadas. Apesar de fisionomias distintas apresentarem efici?ncia de t?cnica de coleta diferenciada, ? relevante a utiliza??o das tr?s t?cnicas para se potencializar ainda mais o registro das esp?cies em ambientes de campos de altitude.

The thesis contributes to the theoretical study of Petri net theory. We conduct boundedness and liveness structural analysis of Synchronized Choice nets (SNC) based on fundamental structures in Petri nets and identified as first-order structures. By studying these structures, the study proposes two ways of preserving good properties: addition of second-order structures or other asymmetric structures. Liveness of these new SNC nets is studied based on the concept of siphons and traps. We prove that SNC nets thus formed are structurally bounded and live. The thesis extends this class of nets to those with pure TP and PT first-order structures and explores its structural and marking conditions. Based on this, we introduce a new class of Synchronized Choice nets called Expanded Synchronized Choice nets.

<p>Den här uppsatsen är skriven inom ramen för ämnet <em>Krigsvetenskap</em> under författarens studier på <em>Yrkesofficersprogrammet</em> 2006-2009 till arméteknisk officer. I <em>Ammunitions- och minröjning i modern konflikt</em> ges läsaren genom deskriptiv metod en exposé över ammunitions- och minröjningens grunder, historia och nutid. Uppsatsens generella syften är att avhandla problematik som svenska ammunitions- och minröjare i sitt yrkesutövande idag kan ställas inför. Och hur delar av den tekniska organisationen och teknisk utrustning för detektion, lokalisering och klassificering av minor, Explosive remnants of war (ERW), Improvised explosive device (IED) och försåt kan bidra till att lösa denna problematik. Författaren genomför utifrån sina intervjuer och litteraturstudier prediktioner av den kommande utvecklingen på området. Prediktionerna innefattar bland annat tydligare teknisk stödorganisation och multisensorplattformar för detektion, lokalisering och klassificering av minor, ERW och IED. I texten redovisas viss forskning från Totalförsvarets forskningsinstitut (FOI) och visst arbete vid Försvarets materielverk (FMV), Totalförsvarets ammunitions- och minröjningscentrum (SWEDEC).</p> / <p>This essay is written in the course of <em>War science</em> during the author’s studies to become an Officer in the technical corps, in the Swedish armed forces. Due to the descriptive method in <em>Explosive Ordnance Disposal and demining in modern conflict </em>the reader gets an exposé of the basics, history, and present time features for the Swedish EOD- and Demining personnel. The main purpose with this essay is to discuss the problems that Swedish Explosive ordnance clearance (EOC) personnel might encounter in their current daily service. The opportunities for parts of the supporting technical corps and the technical equipment for detecting, locating and classifying mines, Explosive remnants of war (ERW), Improvised explosive device (IED) and booby-traps to be at hand in the process of solving these problems are also discussed. From interviews and literature studies the author conducts predictions of the development in the subject area. The predictions contains amongst others a more understandable supporting technical corps and multi-sensing-platforms for detecting, locating and classifying mines, ERW, IED and booby-traps. Some of the research that the Swedish defence research agency (FOI), the Swedish Defence Material Administration (FMV) and the Swedish EOD- and Demining Centre (SWEDEC) have produced is presented in the essay.</p>

A wide variety of novel complementary-metal-oxide-semiconductor (CMOS) devices that are strong contenders for future high-speed and low-noise RF circuits have been evaluated by means of static electrical measurements and low-frequency noise characterizations in this thesis. These novel field-effect transistors (FETs) include (i) compressively strained SiGe channel pMOSFETs, (ii) tensile strained Si nMOSFETs, (iii) MOSFETs with high-k gate dielectrics, (iv) metal gate and (v) silicon-on-insulator (SOI) devices. The low-frequency noise was comprehensively characterized for different types of operating conditions where the gate and bulk terminal voltages were varied. Detailed studies were made of the relationship between the 1/f noise and the device architecture, strain, device geometry, location of the conduction path, surface cleaning, gate oxide charges and traps, water vapour annealing, carrier mobility and other technological factors. The locations of the dominant noise sources as well as their physical mechanisms were investigated. Model parameters and physical properties were extracted and compared. Several important new insights and refinements of the existing 1/f noise theories and models were also suggested and analyzed. The continuing trend of miniaturizing device sizes and building devices with more advanced architectures and complex materials can lead to escalating 1/f noise levels, which degrades the signal-to-noise (SNR) ratio in electronic circuits. For example, the 1/f noise of some critical transistors in a radio receiver may ultimately limit the information capacity of the communication system. Therefore, analyzing electronic devices in order to control and find ways to diminish the 1/f noise is a very important and challenging research subject. We present compelling evidence that the 1/f noise is affected by the distance of the conduction channel from the gate oxide/semiconductor substrate interface, or alternatively the vertical electric field pushing the carriers towards the gate oxide. The location of the conduction channel can be varied by the voltage on the bulk and gate terminals as well by device engineering. Devices with a buried channel architecture such as buried SiGe channel pMOSFETs and accumulation mode MOSFETs on SOI show significantly reduced 1/f noise. The same observation is made when the substrate/source junction is forward biased which decreases the vertical electric field in the channel and increases the inversion layer separation from the gate oxide interface. A 1/f noise model based on mobility fluctuations originating from the scattering of electrons with phonons or surface roughness was proposed. Materials with a high dielectric constant (high-k) is necessary to replace the conventional SiO2 as gate dielectrics in the future in order to maintain a low leakage current at the same time as the capacitance of the gate dielectrics is scaled up. In this work, we have made some of the very first examinations of 1/f noise in MOSFETs with high-k structures composed by layers of HfO2, HfAlOx and Al2O3. The 1/f noise level was found to be elevated (up to 3 orders of magnitude) in the MOSFETs with high-k gate dielectrics compared to the reference devices with SiO2. The reason behind the higher 1/f noise is a high density of traps in the high-k stacks and increased mobility fluctuation noise, the latter possibly due to noise generation in the electron-phonon scattering that originates from remote phonon modes in the high-k. The combination of a TiN metal gate, HfAlOx and a compressively strained surface SiGe channel was found to be superior in terms of both high mobility and low 1/f noise. / QC 20100928

Den här uppsatsen är skriven inom ramen för ämnet Krigsvetenskap under författarens studier på Yrkesofficersprogrammet 2006-2009 till arméteknisk officer. I Ammunitions- och minröjning i modern konflikt ges läsaren genom deskriptiv metod en exposé över ammunitions- och minröjningens grunder, historia och nutid. Uppsatsens generella syften är att avhandla problematik som svenska ammunitions- och minröjare i sitt yrkesutövande idag kan ställas inför. Och hur delar av den tekniska organisationen och teknisk utrustning för detektion, lokalisering och klassificering av minor, Explosive remnants of war (ERW), Improvised explosive device (IED) och försåt kan bidra till att lösa denna problematik. Författaren genomför utifrån sina intervjuer och litteraturstudier prediktioner av den kommande utvecklingen på området. Prediktionerna innefattar bland annat tydligare teknisk stödorganisation och multisensorplattformar för detektion, lokalisering och klassificering av minor, ERW och IED. I texten redovisas viss forskning från Totalförsvarets forskningsinstitut (FOI) och visst arbete vid Försvarets materielverk (FMV), Totalförsvarets ammunitions- och minröjningscentrum (SWEDEC). / This essay is written in the course of War science during the author’s studies to become an Officer in the technical corps, in the Swedish armed forces. Due to the descriptive method in Explosive Ordnance Disposal and demining in modern conflict the reader gets an exposé of the basics, history, and present time features for the Swedish EOD- and Demining personnel. The main purpose with this essay is to discuss the problems that Swedish Explosive ordnance clearance (EOC) personnel might encounter in their current daily service. The opportunities for parts of the supporting technical corps and the technical equipment for detecting, locating and classifying mines, Explosive remnants of war (ERW), Improvised explosive device (IED) and booby-traps to be at hand in the process of solving these problems are also discussed. From interviews and literature studies the author conducts predictions of the development in the subject area. The predictions contains amongst others a more understandable supporting technical corps and multi-sensing-platforms for detecting, locating and classifying mines, ERW, IED and booby-traps. Some of the research that the Swedish defence research agency (FOI), the Swedish Defence Material Administration (FMV) and the Swedish EOD- and Demining Centre (SWEDEC) have produced is presented in the essay.

This thesis considers four nonlinear systems with parametric forcing. The first problem involves an inverted pendulum with asymmetric elastic restraints subjected to harmonic vertical base excitation. On linearizing trigonometric terms the pendulum is governed by an asymmetric Mathieu equation. Solutions to this equation are scaleable. The stability regions in the parameter plane are studied numerically. Periodic solutions at the boundaries of stable regions in the parameter plane are found numerically and then their existence is proved theoretically. The second problem involves use of the method of multiple scales to elucidate the dynamics associated with early and delayed ejection of ions from Paul traps. A slow flow equation is developed to approximate the solution of a weakly nonlinear Mathieu equation to describe ion dynamics in the neighborhood of the nominal stability boundary of ideal traps. Since the solution to the unperturbed equation involves linearly growing terms, some care in identification and elimination of secular terms is needed. Due to analytical difficulties, harmonic balance approximations are used within the formal implementation of the method. The third problem involves the attenuation, caused by weak damping, of harmonic waves through a discrete, periodic structure with wave frequency nominally within the Propagation Zone. Adapting the transfer matrix method and using the harmonic balance for nonlinear terms, a four-dimensional map governing the dynamics is obtained. This map is analyzed by applying the method of multiple scales upto first order. The resulting slow evolution equations give the amplitude decay rate in the structure. The fourth problem involves the dynamic response of a strongly nonlinear single-degree-of-freedom oscillator under a constant amplitude, parametric, periodic, impulsive forcing, e.g., a pendulum with strongly nonlinear torsional spring that is periodically struck in the axial direction. Single-term harmonic balance gives an approximate, but explicit, 2-dimensional map governing the dynamics. The map exhibits many fixed points (both stable and unstable), higher period orbits, transverse intersections of stable and unstable manifolds of unstable fixed points, and chaos.

Les polynucléaires neutrophiles (PN) sont des cellules essentielles au cours de la réponse immunitaire innée ; recrutés rapidement au site inflammatoire où ils participent à la phase aigüe, ils vont aussi contribuer à la résolution de l'inflammation. Ils peuvent en effet moduler la réponse adaptative par interaction avec les lymphocytes (Ly) ou les cellules dendritiques (DC) via des médiateurs solubles ou des interactions cellulaires directes. Les Neutrophil Extracellular Traps (NETs) libérés par les PN activés pourraient jouer un rôle important dans ce contexte. Les NETs sont des filaments de chromatine décondensée associés à des protéines issues principalement des granulations et du cytoplasme. Ils sont essentiels dans la réponse anti-infectieuse mais semblent également impliqués dans la physiopathologie de certaines maladies auto-immunes et inflammatoires. L'objectif de ce travail a été d'évaluer les effets des NETs sur la maturation des DC dans un contexte inflammatoire au cours duquel les PN et les DC peuvent co-exister, assurant ainsi un pont entre immunité innée et immunité adaptative. La première partie de ce travail a consisté à développer un modèle de production, isolement et caractérisation des NETs issus de PN sanguins humains. L'ionophore de calcium A23187 a été choisi pour induire les NETs et l'enzyme de restriction AluI a permis la récupération de fragments de NETs de taille hétérogène. Certains des composants de ces NETs sont quantifiables (ADN, élastase, histone 3 en particulier), et nous avons montré qu'ils conservaient leurs capacités bactéricides in vitro. Ces échantillons de NETs constituent donc un outil biologique standardisé, permettant d'évaluer leurs effets sur des cellules ou des tissus. Dans la deuxième partie de ce travail, nous avons mis en évidence que ces NETs purifiés régulaient négativement la maturation de moDC induites par le LPS (expression de HLA-DR, CD80, CD83, CD86 et production de TNFα, IL-12, IL-6, IL-23). De plus, les NETs diminuent la capacité de ces moDC à induire la prolifération des LyT, et leur polarisation est modulée en favorisant la production de cytokines de type Th2 (IL-5 et IL-13) aux dépens de cytokines de types Th1 (INFγ) et Th17 (IL-17). De manière intéressante, la capacité de migration des moDC activées par le LPS n'est pas modifiée en présence de NETs. En résumé, ces résultats suggèrent que les NETs pourraient jouer un rôle immunorégulateur sur la maturation des moDC dans des conditions inflammatoires. Les NETs produits par les PN activés pourraient ainsi participer à la régulation indispensable de la réponse inflammatoire.