Influência do período de exposição no parasitismo Telenomus remus em ovos de Corcyra cephalonica.

Objetivou-se avaliar as características biológicas e a porcentagem de parasitismo de T. remus, em ovos do hospedeiro alternativo C. cephalonica sob diferentes períodos de exposição ao parasitismo, para selecionar o melhor método de criação do parasitoide neste hospedeiro. O experimento foi conduzido em sala climatizada (T: 25±2°C; UR: 70±10%; Fotofase: 12h), com delineamento inteiramente casualizado sendo três tratamentos (períodos de exposição: 24, 48 e 72h) e 20 repetições. Em tubos de vidro de fundo chato, foram colocados 30 ovos parasitados de S. frugiperda. 24h após a emergência dos adultos, aproximadamente 100 ovos inviabilizados de C. cephalonica, foram colados com cola atóxica (30%) em cartelas e oferecidos aos parasitoides. O parasitismo foi permitido por diferentes períodos, conforme cada tratamento. Os parâmetros biológicos avaliados foram: porcentagem de parasitismo, viabilidade e razão sexual. Não houve diferença significativa entre os tratamentos avaliados, sendo que as variações verificadas entre os períodos de exposição ao parasitismo (24, 48 e 72h) foram: porcentagem de parasitismo (48,27%; 60,96%; 57,78%), viabilidade (80,15%; 74,37% e 79,98%) e razão sexual (0,66; 0,66 e 0,65 fêmeas), respectivamente. Assim, estes resultados indicam que não é necessário um maior período de exposição ao parasitismo quando T. remus é criado em ovos do hospedeiro alternativo C. cephalonica, mesmo que exista uma tendência a maior parasitismo nos maiores períodos de exposição. Ainda, a baixa porcentagem de parasitismo pode estar diretamente correlacionada o comportamento do inseto visto que o mesmo é criado em ovos do seu hospedeiro natural (Spodoptera frugiperda) por sucessivas gerações, e que pode ser confirmado com os altos valores de viabiliade, tornando C. cephalonica um potencial hospedeiro alternativo

Computation of schenberg response function by using finite element modelling

Schenberg is a detector of gravitational waves resonant mass type, with a central frequency of operation of 3200 Hz. Transducers located on the surface of the resonating sphere, according to a distribution half-dodecahedron, are used to monitor a strain amplitude. The development of mechanical impedance matchers that act by increasing the coupling of the transducers with the sphere is a major challenge because of the high frequency and small in size. The objective of this work is to study the Schenberg response function obtained by finite element modeling (FEM). Finnaly, the result is compared with the result of the simplified model for mass spring type system modeling verifying if that is suitable for the determination of sensitivity detector, as the conclusion the both modeling give the same results.Sao Paulo Federal Institute Rua Pedro Vicente 625, 01109-010 Sao Paulo, SP, BrazilFederal University of Sao Paulo, Department of Exact and Earth Sciences Rua Sao Nicolau 120, 09913-030 Diadema, SP, BrazilFederal University of Sao Paulo, Department of Exact and Earth Sciences Rua Sao Nicolau 120, 09913-030 Diadema, SP, BrazilWeb of Scienc

Thermal connection and vibrational isolation: an elegant solution for two problems

Schenberg is a detector of gravitational waves resonant mass type, with a central frequency of operation of 3200 Hz. Transducers located on the surface of the resonating sphere, according to a distribution half-dodecahedron, are used to monitor a strain amplitude. To improve the performance of the detector it is essential to decrease the temperature, then it will be cooled down, this temperature could reach as low as 50 mK. This refrigerator produces vibration noise that could compromise the performance of Schenberg detector. In this work we the study such vibration noise and how it could be minimized proposing a new connection from the dilution refrigerator to the sphere suspension. The vibration attenuation is studied by finite element modeling (FEM) and an attenuation higher than 1024 is found, higher enough to note compromise the performance of Schenberg detector.Sao Paulo Federal Institute Rua Pedro Vicente 625, 01109-010 Sao Paulo, SP, BrazilFederal University of Sao Paulo, Department of Exact and Earth Sciences Rua Sao Nicolau 120, 09913-030 Diadema, SP, BrazilINPE Astrophysics Division, Sao Jose dos Campos, SP, 12227-010, BrazilFederal University of Sao Paulo, Department of Exact and Earth Sciences Rua Sao Nicolau 120, 09913-030 Diadema, SP, BrazilWeb of Scienc

Development of glass-stalks-unsaturated polyester hybrid composites

The aim of this study is to investigate the possibility to use agro-residues of the vinification process as a cheaper and eco-friendly fillers to prepare unsaturated polyester composites for interior design building sector. Experimental unsaturated polyester–based resin composite samples, reinforced with grape stalks, were prepared by a simple casting technique. The glass microspheres were added in the mixing to increase the mechanical and physical properties of the final materials. A silane coupling agent was used to increase the interface adhesion between resin and grape stalks. The samples were subjected to several tests. Unfilled samples were analyzed by Differential Scanning calorimetry (DSC). Prepared silanized and non-silanized composites were completely characterized in order to study the effect of stalk fibers concentration on the mechanical, chemical and physical properties. The results showed that mechanical and physical properties for silanized composites were superior to non-silanized composites. The presence of stalks, up to 50% wt. increased Young's Modulus preserving a satisfactory tensile strength and hardness in comparison with the neat resin properties. Then, the final results showed that grape stalks from winemaking can be satisfactory used as natural filler resource to produce composites for interior furniture