992 resultados para Complex reflection coefficient


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The Caridina indistincta complex is a group of closely related atyid shrimps that inhabit coastal freshwater streams throughout north-eastern Australia. Using mitochondrial DNA sequence data (cytochrome oxidase 1, CO1), we (1) inferred the timing of speciation in the C. indistincta group and (2) examined the intraspecific phylogeographic patterns within the group. Assuming a shrimp-specific rate of CO1 evolution, the level of sequence divergence among species suggests that speciation took place during the Miocene epoch. Within one widespread mainland species, phylogeographic patterns suggest strong geographic 'regionalisation' of mtDNA lineages that are most likely of Pleistocene origin. By contrast, another species comprises two highly divergent mtDNA lineages that occur in sympatry. We suggest that although Pleistocene sea-level regressions appear important in generating population-level phylogeographic patterns, these events were largely unimportant in the formation of species in this group.

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A research program on atmospheric boundary layer processes and local wind regimes in complex terrain was conducted in the vicinity of Lake Tekapo in the southern Alps of New Zealand, during two 1-month field campaigns in 1997 and 1999. The effects of the interaction of thermal and dynamic forcing were of specific interest, with a particular focus on the interaction of thermal forcing of differing scales. The rationale and objectives of the field and modeling program are described, along with the methodology used to achieve them. Specific research aims include improved knowledge of the role of surface forcing associated with varying energy balances across heterogeneous terrain, thermal influences on boundary layer and local wind development, and dynamic influences of the terrain through channeling effects. Data were collected using a network of surface meteorological and energy balance stations, radiosonde and pilot balloon soundings, tethered balloon and kite-based systems, sodar, and an instrumented light aircraft. These data are being used to investigate the energetics of surface heat fluxes, the effects of localized heating/cooling and advective processes on atmospheric boundary layer development, and dynamic channeling. A complementary program of numerical modeling includes application of the Regional Atmospheric Modeling System (RAMS) to case studies characterizing typical boundary layer structures and airflow patterns observed around Lake Tekapo. Some initial results derived from the special observation periods are used to illustrate progress made to date. In spite of the difficulties involved in obtaining good data and undertaking modeling experiments in such complex terrain, initial results show that surface thermal heterogeneity has a significant influence on local atmospheric structure and wind fields in the vicinity of the lake. This influence occurs particularly in the morning. However, dynamic channeling effects and the larger-scale thermal effect of the mountain region frequently override these more local features later in the day.

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In this study, a combination of recA-based PCR assays and 16S rDNA restriction fragment length polymorphism (RFLP) analysis was used to determine the genomovar diversity of clinical Burkholderia cepacia complex isolates. Twenty-eight isolates were prospectively collected from patients attending a large Australian adult cystic fibrosis (CF) unit, 22 isolates were referred from other Australian CF units and a further eight isolates originated from patients without CF. The 28 prospectively collected isolates were distributed amongst the following genomovars: Burkholderia cepacia genomovar I (28.6%), Burkholderia multivorans (21.4%), Burkholderia cepacia genomovar III (39.3%), Burkholderia vietnamiensis (3.6%) and Burkholderia ambifaria (7.1%). The results of this study highlight the usefulness of 16S rDNA RFLP typing for the identification of other Burkholderia spp. and non-fermenting gram-negative bacteria.

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The entire internal transcribed spacer ( ITS) region, including the 5.8S subunit of the nuclear ribosomal DNA ( rDNA), was sequenced by direct double-stranded sequencing of polymerase chain reaction (PCR) amplified fragments. The study included 40 Sporobolus ( Family Poaceae, subfamily Chloridoideae) seed collections from 14 putative species ( all 11 species from the S. indicus complex and three Australian native species). These sequences, along with those from two out-group species [ Pennisetum alopecuroides ( L.) Spreng. and Heteropogon contortus ( L.) P. Beauv. ex Roemer & Schultes, Poaceae, subfamily Panicoideae], were analysed by the parsimony method (PAUP; version 4.0b4a) to infer phylogenetic relationships among these species. The length of the ITS1, 5.8S subunit and ITS2 region were 222, 164 and 218 base pairs ( bp), respectively, in all species of the S. indicus complex, except for the ITS2 region of S. diandrus P. Beauv. individuals, which was 217 bp long. Of the 624 characters included in the analysis, 245 ( 39.3%) of the 330 variable sites contained potential phylogenetic information. Differences in sequences among the members of the S. pyramidalis P. Beauv., S. natalensis (Steud.) Dur & Schinz and S. jacquemontii Kunth. collections were 0%, while differences ranged from 0 to 2% between these and other species of the complex. Similarly, differences in sequences among collections of S. laxus B. K. Simon, S. sessilis B. K. Simon, S. elongatus R. Br. and S. creber De Nardi were 0%, compared with differences of 1-2% between these four species and the rest of the complex. When comparing S. fertilis ( Steud.) Clayton and S. africanus (Poir.) Robyns & Tourney, differences between collections ranged from 0 to 1%. Parsimony analysis grouped all 11 species of the S. indicus complex together, indicating a monophyletic origin. For the entire data set, pair-wise distances among members of the S. indicus complex varied from 0.00 to 1.58%, compared with a range of 20.08-21.44% among species in the complex and the Australian native species studied. A strict consensus phylogenetic tree separated 11 species of the S. indicus complex into five major clades. The phylogeny, based on ITS sequences, was found to be congruent with an earlier study on the taxonomic relationship of the weedy Sporobolus grasses revealed from random amplified polymorphic DNA ( RAPD). However, this cladistic analysis of the complex was not in agreement with that created on past morphological analyses and therefore gives a new insight into the phylogeny of the S. indicus complex.

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The ability to generate enormous random libraries of DNA probes via split-and-mix synthesis on solid supports is an important biotechnological application of colloids that has not been fully utilized to date. To discriminate between colloid-based DNA probes each colloidal particle must be 'encoded' so it is distinguishable from all other particles. To this end, we have used novel particle synthesis strategies to produce large numbers of optically encoded particle suitable for DNA library synthesis. Multifluorescent particles with unique and reproducible optical signatures (i.e., fluorescence and light-scattering attributes) suitable for high-throughput flow cytometry have been produced. In the spectroscopic study presented here, we investigated the optical characteristics of multi-fluorescent particles that were synthesized by coating silica 'core' particles with up to six different fluorescent dye shells alternated with non-fluorescent silica 'spacer' shells. It was observed that the diameter of the particles increased by up to 20% as a result of the addition of twelve concentric shells and that there was a significant reduction in fluorescence emission intensities from inner shells as an increasing number of shells were deposited.

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The pentadentate chelating agent, 2,6-diacetylpyridinebis(S-benzyldithiocarbazate) (H2SNNNS) reacts with zinc(II) and cadmium(II) ions forming stable complexes of empirical formula, [M(SNNNS)] (M=Zn2+, Cd2+; SNNNS2 =doubly deprotonated anionic form of the Schiff base). These complexes have been characterized by a variety of physico-chemical techniques. IR and H-1 NMR spectral evidence indicate that the Schiff base coordinates to the zinc(II) and cadmium(II) ions via the pyridine nitrogen atoms, the azomethine nitrogen atoms and the mercaptide sulfur atoms. The crystal and molecular structure of the zinc(II) complex has been determined by X-ray diffraction. The complex is a dimer in which the pyridine nitrogen atom,the azomethine nitrogen atom and the thiolate sulfur atom from one ligand coordinate to one of the zinc(II) ions whereas the azomethine and thiolate sulfur atoms from another ligand complete pentacoordination around the zinc(II) ion, the ligands being coordinated in their deprotonated forms. The coordination geometry about each zinc(II) can be considered as intermediate between a square-pyramid and trigonal-bipyramid. The cadmium(II) complex is also assigned with a dimeric structure. (C) 2003 Elsevier Ltd. All rights reserved.

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Este texto trata do tema da pesquisa "com" o cotidiano. O interesse é provocar uma permanente abertura para a reflexão e o debate sobre o cotidiano e a pesquisa com o cotidiano, e não fechar a questão com uma proposta sistemática. Vale-se dos estudos desenvolvidos em escolas públicas do Estado do Espírito Santo no período de 1999 a 2004, cujo principal objetivo foi desencadear, entre os praticantes do cotidiano escolar, práticas de intervenção nos "currículos" e na "formação continuada", assumidos como processos complexos que se interpenetram em meio às redes de saberesfazeres tecidas e partilhadas pelos sujeitos das escolas. Podemos inferir, a partir das pistas encontradas, que o cotidiano exige dos pesquisadores em educação outras possibilidades teórico-metodológicas, diferentes daquelas herdadas da modernidade, para superar o aprisionamento do cotidiano em categorias prévias e assegurar a impossibilidade de usarmos o singular para tratar da diversidade que se manifesta na vida.

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Criada em agosto de 2008, a revista em quadrinhos “Turma da Mônica Jovem”, ou TMJ, como é conhecida por seus leitores, tem estilo mangá e traz os mesmos personagens moradores do bairro Limoeiro, agora, adolescentes e com características bem distintas da turma tradicional. A presente pesquisa procurou desenvolver uma análise crítica de TMJ, dentro dos pressupostos teóricos e metodológicos da semiótica discursiva, buscando responder as questões: como a problemática do consumo é apropriada pela revista? Que estratégias enunciativas são utilizadas para inscrever o público infantojuvenil em seu discurso? A revisão de literatura faz uma triangulação dos conceitos norteadores do estudo: Quadrinhos, Consumo Infantil e Semiótica, trazendo, no centro do triângulo, a Educação, área de conhecimento principal da pesquisa e conectora dos três outros campos. Realizamos uma análise semiótica de um corpus composto por sete edições de TMJ que trouxeram como tema principal problemática relacionada à sociedade de consumo contemporânea, a partir de um universo de revistas publicadas, no período de 2012 a 2014. Dentre as categorias de consumo pré-estabelecidas ou que emergiram do discurso de TMJ, contemplamos: o consumo consciente, o consumo conspícuo, o consumo moralista e o consumo de cultura midiática. Por meio da técnica do grupo focal, desenvolvemos uma conversa com os leitores de TMJ, buscando entender como se dá a apreensão da problemática do consumo por eles, bem como que impactos essa apreensão tem para uma maior atratividade da publicação, dentre outros objetivos específicos investigados, nesse encontro. Durante a realização de três grupos, intitulados Leitores Iniciantes, Leitores Assíduos e Leitores Esporádicos, os agrupamos em duas categorias relacionadas ao campo do consumo e, também, da semiótica. O grupo do Pertencimento conhece e interage com a revista, em profundidade, promovendo um ajuste de sensibilidade entre o enunciatário (leitor) e o enunciador (revista), com características do “parecer ser e ser”. O grupo da Emulação deseja pertencer ao grupo dos leitores assíduos, mas como não possui as características para tal, as busca por meio da imitação, dentro de um regime do “parecer ser, mas não ser”. Os resultados da pesquisa apontam que o consumo está muito presente em TMJ, tendo aparecido como temática principal, em mais da metade das revistas analisadas. Ainda, ele pode ser considerado como tema central das histórias da turma, principalmente, no momento em que a revista utiliza sua plasticidade, na figurativização dos personagens e ambientes das histórias, para difundir um mundo de consumo a essas crianças e adolescentes leitores. Embora as revistas que se enquadraram nas categorias de consumo consciente e consumo moralista busquem passar alguns conselhos e ensinamentos para seus leitores, são as categorias de consumo conspícuo e consumo de cultura midiática, tratadas de forma pouco crítica e, por vezes, irresponsável que possuem maior grau de apreensão por parte do leitor, conferindo atratividade à revista. Entre outras conclusões, podemos afirmar que o discurso de TMJ se utiliza de narrativas simples (lineares e pouco complexas), bem como de uma figuratividade e de temáticas repetitivas, oferecendo a seus leitores pouco debate e reflexão, sendo um discurso da reprodução, sem aprofundamento, do dia-a-dia dessas crianças e adolescentes que, apesar de falar delas e para elas, não inclui muitas temáticas relevantes ao seu universo.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Comunicação, Programa de Pós-Graduação em Comunicação, 2016.

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This work presents a reflection on Design education and specifically on the role of Drawing in this area. As a subject, Design has expanded its field of action expanding into new areas such as Experience Design or Service Design. It became necessary for the designer to have more than an education based on technological knowledge or know-how. Many authors like Meredith Davis, Don Norman or Jamie Hobson point out the urgency to review the curricula of Design courses because nowadays “… design is more than appearance, design is about interaction, about strategy and about services. Designers change social behavior” (Norman 2011). When shifting from a product-centered design to a person-centered design (in a structure, a service or in a relationship) what should the function of drawing in a design course be? What should its curriculum be? Our work methodology will be to confront today’s perspectives on design theory and practice in an attempt to add to the discussion on the methodological strategies in design teaching in the contemporary context.

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This work presents a reflection on Design education and specifically on the role of Drawing in this area. As a subject, Design has expanded its field of action expanding into new areas such as Experience Design or Service Design. It became necessary for the designer to have more than an education based on technological knowledge or know-how. Many authors like Meredith Davis, Don Norman or Jamie Hobson point out the urgency to review the curricula of Design courses because nowadays “ … design is more than appearance, design is about interaction, about strategy and about services. Designers change social behavior” (Norman, 2011) When shifting from a product-centered design to a person-centered design (in a structure, a service or in a relationship) what should the function of drawing in a design course be? What should its curriculum be? Our work methodology will be to confront today’s perspectives on design theory and practice in an attempt to add to the discussion on the methodological strategies in design teaching in the contemporary context.

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This work demonstrates that the theoretical framework of complex networks typically used to study systems such as social networks or the World Wide Web can be also applied to material science, allowing deeper understanding of fundamental physical relationships. In particular, through the application of the network theory to carbon nanotubes or vapour-grown carbon nanofiber composites, by mapping fillers to vertices and edges to the gap between fillers, the percolation threshold has been predicted and a formula that relates the composite conductance to the network disorder has been obtained. The theoretical arguments are validated by experimental results from the literature.

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Nitrogen has a complex dynamics in the soil-plant-atmosphere system. N fertilizers are subject to chemical and microbial transformations in soils that can result in significant losses. Considering the cost of fertilizers, the adoption of good management practices like fertigation could improve the N use efficiency by crops. Water balances (WB) were applied to evaluate fertilizer N leaching using 15N labeled urea in west Bahia, Brazil. Three scenarios (2008/2009) were established: i) rainfall + irrigation the full year, ii) rainfall only; and iii) rainfall + irrigation only in the dry season. The water excess was considered equal to the deep drainage for the very flat area (runoff = 0) with a water table located several meters below soil surface (capillary rise = 0). The control volume for water balance calculations was the 0 - 1 m soil layer, considering that it involves the active root system. The water drained below 1 m was used to estimate fertilizer N leaching losses. WB calculations used the mathematic model of Penman-Monteith for evapotranspiration, considering the crop coefficient equal to unity. The high N application rate associated to the high rainfall plus irrigation was found to be the main cause for leaching, which values were 14.7 and 104.5 kg ha-1 for the rates 400 and 800 kg ha-1 of N, corresponding to 3.7 and 13.1 % of the applied fertilizer, respectively.

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Hand and finger tracking has a major importance in healthcare, for rehabilitation of hand function required due to a neurological disorder, and in virtual environment applications, like characters animation for on-line games or movies. Current solutions consist mostly of motion tracking gloves with embedded resistive bend sensors that most often suffer from signal drift, sensor saturation, sensor displacement and complex calibration procedures. More advanced solutions provide better tracking stability, but at the expense of a higher cost. The proposed solution aims to provide the required precision, stability and feasibility through the combination of eleven inertial measurements units (IMUs). Each unit captures the spatial orientation of the attached body. To fully capture the hand movement, each finger encompasses two units (at the proximal and distal phalanges), plus one unit at the back of the hand. The proposed glove was validated in two distinct steps: a) evaluation of the sensors’ accuracy and stability over time; b) evaluation of the bending trajectories during usual finger flexion tasks based on the intra-class correlation coefficient (ICC). Results revealed that the glove was sensitive mainly to magnetic field distortions and sensors tuning. The inclusion of a hard and soft iron correction algorithm and accelerometer and gyro drift and temperature compensation methods provided increased stability and precision. Finger trajectories evaluation yielded high ICC values with an overall reliability within application’s satisfying limits. The developed low cost system provides a straightforward calibration and usability, qualifying the device for hand and finger tracking in healthcare and animation industries.