Optimized Multimode Interference Fiber Based Refractometer in A Reflective Interrogation Scheme

A fiber based refractometer in a reflective interrogation scheme is investigated and optimized. A thin gold film was deposited on the tip of a coreless fiber section, which is spliced with a single mode fiber. The coreless fiber is a multimode waveguide, and the observed effects are due to multimode interference. To investigate and optimize the structure, the multimode part of the sensor is built with 3 different lengths: 58 mm, 29 mm and 17 mm. We use a broadband light source ranging from 1475 nm to 1650 nm and we test the sensors with liquids of varying refractive indices, from 1.333 to 1.438. Our results show that for a fixed wavelength, the sensor sensitivity is independent of the multimode fiber length, but we observed a sensitivity increase of approximately 0.7 nm/RIU for a one-nanometer increase in wavelength

Produção orgânica de uvas destinadas à elaboração de vinhos finos como diferencial mercado no Submédio do Vale do São Francisco.

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Alterations in brain connectivity due to plasticity and synaptic delay

Brain plasticity refers to brain's ability to change neuronal connections, as a result of environmental stimuli, new experiences, or damage. In this work, we study the effects of the synaptic delay on both the coupling strengths and synchronisation in a neuronal network with synaptic plasticity. We build a network of Hodgkin-Huxley neurons, where the plasticity is given by the Hebbian rules. We verify that without time delay the excitatory synapses became stronger from the high frequency to low frequency neurons and the inhibitory synapses increases in the opposite way, when the delay is increased the network presents a non-trivial topology. Regarding the synchronisation, only for small values of the synaptic delay this phenomenon is observed

Identification and field evaluation of a new blend of the sex pheromone of Hypsipyla grandella.

Made available in DSpace on 2017-12-20T23:22:11Z (GMT). No. of bitstreams: 1 241601248632PB.pdf: 539416 bytes, checksum: d7ed3c0ad491c1b03ea8ad3d2540ccea (MD5) Previous issue date: 2017-12-20bitstream/item/169355/1/24160-124863-2-PB.pd

Produção de raízes de mandioca em sistemas agroflorestais seqüenciais submetidos a diferentes manejos de adubações verde e fertilizantes no Nordeste paraense.

A agricultura tradicional na Amazônia tem sido afetada pelo crescimento populacional, pela crescente minifundização dos sistemas agrários, redução dos períodos de pousio, altas taxas de desmatamento e emissão de gases que comprometem a continuidade desse modelo. A associação de práticas de corte e queima com as modernas tecnologias ampliou os efeitos negativos da agricultura para o ambiente e sociedade. As unidades de produção familiar contribuem significativamente para a economia rural da Amazônia e representam um componente essencial para a obtenção de níveis sustentáveis de desenvolvimento, segurança alimentar e geração de emprego e renda. Logo, torna-se fundamental oferecer alternativas para alcançar a sustentabilidade das unidades de produção familiar. No ano de 2005 foi iniciado em Igarapé-Açu/Pa um experimento de longa duração para estudar a sustentabilidade de sistemas de produção submetidos a diferentes manejos de adubações verde (crotalária, mucuna-preta, titônia, ingá e guandu) e fertilizantes (fosfato natural de Arad e NPK 10-28-20). O objetivo do presente trabalho é apresentar os resultados obtidos com a produção da mandioca na terceira fase deste experimento. A produção média de raízes frescas de mandioca indicou um aumento da produtividade de raízes devido à adubação com fosfato natural, sendo os maiores valores médios obtidos nas parcelas que receberam duas aplicações do fosfato (primeira e terceira fase).Editores técnicos: Roberto Porro, Milton Kanashiro, Maria do Socorro Gonçalves Ferreira, Leila Sobral Sampaio e Gladys Ferreira de Sousa

Complementary action of chemical and electrical synapses to perception

Acknowledgements This study was possible by partial financial support from the following agencies: Fundação Araucária, EPSRC-EP/I032606/1, CNPq No. 441553/2014-1, CAPES No. 17656-12-5 and Science Without Borders Program— Process Nos. 17656125, 99999.010583/2013-00 and 245377/2012-3.Peer reviewedPostprin

Vibratory signals of four neotropical stink bug species.

The stink bugs Acrosternum impicticorne, Euschistus heros, Piezodorus guildinii and Thyanta perditor (Heteroptera: Pentatomidae) feed and mate on the same host plants and constitute major components of the soybean pest complex in Brazil. During mating, they communicate with species and sex-specific vibratory signals whose spectral properties are characteristic of the subfamily Pentatominae. Songs differ between species in the time structure and amplitude modulation of their units. The repertoire of A. impicticorne, E. heros and T. perditor fits into the scheme described for most investigated stink bugs: females call with a sequence of pulses that differ between species in their duration and repetition rate, and males respond with courtship songs of species-specific temporal structure and amplitude modulation of complex pulse trains. Female calling and male courtship songs are the main constituents of vibratory communication between sexes in the mating period. The other vibratory emissions appear to represent either transitional songs, support recognition during close-range courtship, or are involved in male rivalry. The first recorded vibratory emissions of P. guildinii confirm that the genus Piezodorus represents an exception within the Pentatominae. Irregularly repeated female vibratory signals of P. guildinii do not trigger typical male courtship responses as they would in the small stink bugs Holcostethus strictus and Murgantia histrionica. On the other hand, complex rivalry with extensive frequency modulation of pulses, as also described in Piezodorus lituratus, opens a new insight into the role of vibratory communication in stink bug

Vibratory communication and its relevance to reproductive isolation in two sympatric stink bug species (Hemiptera: Pentatomidae: Pentatominae).

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