2,885 research outputs found
Soroprevalência da artrite encefalite caprina (CAE) em reprodutores criados no município de Afonso Bezerra, RN.
No full textSoroprevalência da artrite encefalite caprina (CAE) em reprodutores criados no município de Afonso Bezerra, RN - Este trabalho foi desenvolvido com objetivo de realizar a prevalência da artrite-encefalite caprina (AEC) em reprodutores criados no município de Afonso Bezerra – RN
Static And Dynamic Properties Of Fibonacci Multilayers
No full textWe theoretically investigate static and dynamic properties of quasiperiodic magnetic multilayers. We considered identical ferromagnetic layers separated by non-magnetic spacers with two different thicknesses chosen based on the Fibonacci sequence. Using parameters for Fe/Cr, the minimum energy was determined and the equilibrium magnetization directions found were used to calculate magnetoresistance curves. Regarding dynamic behavior, ferromagnetic resonance (FMR) curves were calculated using an approximation known from the literature. Our numerical results illustrate the effects of quasiperiodicity on the static and dynamic properties of these structures. © 2013 American Institute of Physics.11317Grünberg, P., Schreiber, R., Pang, Y., Brodsky, M.B., Sowers, H., (1986) Phys. Rev. Lett., 57, p. 2442. , 10.1103/PhysRevLett.57.2442Baibich, M.N., Broto, J.M., Fert, A., Nguyen Van Dau, F., Petroff, F., Etienne, P., Creuzet, G., Chazelas, J., (1988) Phys. Rev. Lett., 61, p. 2472. , 10.1103/PhysRevLett.61.2472Binasch, G., Grünberg, P., Saurenbach, F., Zinn, W., (1989) Phys. Rev. B, 39, p. 4828. , 10.1103/PhysRevB.39.4828Prinz, G.A., (1998) Science, 282, p. 1660. , 10.1126/science.282.5394.1660Kools, J.C.S., (1996) IEEE Trans. Magn., 32, p. 3165. , 10.1109/20.508381Stiles, M.D., Zangwill, A., (2002) Phys. Rev. B, 66, p. 014407. , 10.1103/PhysRevB.66.014407Lakys, Y., Zhao, W.S., Devolder, T., Zhang, Y., Klein, J.O., Ravelosona, D., Chappert, C., (2012) IEEE Trans. Magn., 48, p. 2403. , 10.1109/TMAG.2012.2194790Chaves, R.C., Cardoso, S., Ferreira, R., Freitas, P.P., (2011) J. Appl. Phys, 109, pp. 07E506. , 10.1063/1.3537926Vedyayev, A., Dieny, B., Ryzhanova, N., Genin, J.B., Cowache, C., (1994) Europhys. Lett., 25, p. 465. , 10.1209/0295-5075/25/6/012Albuquerque, E.L., Cottam, M.G., (2004) Polaritons in Periodic and Quasiperiodic Structures, , (Elsevier, Amsterdam)Bezerra, C.G., Albuquerque, E.L., (1997) Physica A, 245, p. 379. , 10.1016/S0378-4371(97)00309-9Bezerra, C.G., De Araujo, J.M., Chesman, C., Albuquerque, E.L., (1999) Phys. Rev. B, 60, p. 9264. , 10.1103/PhysRevB.60.9264Bezerra, C.G., De Araujo, J.M., Chesman, C., Albuquerque, E.L., (2001) J. Appl. Phys., 89, p. 2286. , 10.1063/1.1340600Bezerra, C.G., Cottam, M.G., (2002) J. Magn. Magn. Mater., 240, p. 529. , 10.1016/S0304-8853(01)00838-1Bezerra, C.G., Cottam, M.G., (2002) Phys. Rev. B, 65, p. 054412. , 10.1103/PhysRevB.65.054412Mauriz, P.W., Albuquerque, E.L., Bezerra, C.G., (2002) J. Phys.: Condens. Matter, 14, p. 1785. , 10.1088/0953-8984/14/8/308Fullerton, E.E., Conover, M.J., Mattson, J.E., Sowers, C.H., Bader, S.D., (1993) Phys. Rev. B, 48, p. 15755. , 10.1103/PhysRevB.48.15755Machado, L.D., Bezerra, C.G., Correa, M.A., Chesman, C., Pearson, J.E., Hoffmann, A., (2012) Phys. Rev. B, 85, p. 224416. , 10.1103/PhysRevB.85.22441
Repeated fed-batch cultivation of Arthrospira (Spirulina) platensis using urea as nitrogen source
No full textArthospira (Spirulina) platensis (Nordstedt) Gomont was autotrophically cultivated for biomass production in repeated fed-batch process using urea as nitrogen source, with the aim of making large-scale production easier, increasing cell productivity and then reducing the production costs. It was investigated the influence or the ratio of renewed volume to total volume (R), the Urea feeding time (t(f)) and the number of successive repealed fed-batch cycles on the maximum cell concentration (X(m)), cell productivity (P(x)), nitrogen-to-cell conversion yield (Y(x/n)), maximum specific growth rate (mu(m)) and protein content of, dry biomass. The experimental results demonstrated chat R=0.80 and t(f) = 6d were the best cultivation conditions, being able to simultaneously ensure, throughout the three fed-batch cycles, the highest average values of three of the five responses (X(m) = 2101 +/- 113 mg L(-1), P(x) = 219 +/- 13 mg L(-1) d(-1) and Y(x/n) = 10.3 +/- 0.8,g g(-1)). (C) 2008 Elsevier B.V. All rights reserved.FAPESP, Brazil[04/04004-1]FAPESP, Brazil[04/04012-4
Influência do fotoperíodo no parasitismo de Cleruchoides noackae em ovos de Thaumastocoris peregrinus.
No full textEspécies de Eucalyptus são importantes para a economia brasileira e os plantios ocupam aproximadamente 5,5 milhões de hectares. O percevejo bronzeado do eucalipto Thaumastocoris peregrinusé uma praga exótica da cultura. A microvespa parasitoide Cleruchoides noackae (Hymenoptera: Mymaridae) é a principal alternativa de controle utilizada. O objetivo deste trabalho foi avaliar a influência do fotoperíodo no parasitismo de C. noackae, em ovos de T. peregrinus. Na montagem do experimento foram utilizados frascos de poliestireno contendo dez ovos de T. peregrinuspara cada casal de C. noackae. Os parasitoides foram alimentados com uma solução de mel a 50% fornecidos em tiras de papel filtro. Os frascos contendo os parasitoides foram mantidos a 24 °C ± 2 °C, 70% ± 10% UR e fotoperíodo de 12L:12D, por 24 horas. Após este período, os casais foram removidos e os ovos colocados em câmaras climatizadas tipo BOD a 24 °C ± 2 °C, 70% ± 10% UR, nos seguintes tratamentos de fotoperíodo: 24L:0D, 0L:24D, 12L:12D, 16L:8D e 8L:16D. Após a emergência dos parasitoides, foram montados casais com a geração F1, os quais foram mantidos nos mesmos tratamentos e condições descritas. O período de desenvolvimento e a razão sexual da geração parental e a taxa de parasitismo da geração F1 foram avaliados. O período de desenvolvimento de C. noackae foi menor no regime de fotoperíodo 8L:16D e semelhante nos demais avaliados. O regime de fotoperíodo não afetou a razão sexual do parasitoide. O fotoperíodo afetou a taxa de parasitismo de C. noackae, sendo superior para insetos mantidos por 16 horas na presença de luz e 8 horas no escuro. A definição do melhor regime de fotoperíodo poderá otimizar a produção de C. noackae em laboratório
Influence of pH, temperature, and urea molar flowrate onArthrospira platensis fed-batch cultivation: A kinetic and thermodynamic approach
No full textArthrospira platensis was cultivated photoautotrophically at 6.0 klux light intensity in 5.0-L open tanks, using a mineral medium containing urea as nitrogen source. Fed-batch experiments were performed at constant flowrate. A central composite factorial design combined to response surface methodology (RSM) was utilized to determine the relationship between the selected response variables (cell concentration after 10 days, Xm, cell productivity, PX, and nitrogen-to-cell conversion factor, YX/N) and codified values of the independent variables (pH, temperature, T, and urea flowrate, K)
LABORATORY BREEDING OF PHORTICA SPP. (DIPTERA: DROSOPHILIDAE),VECTORS OF THE ZOONOTIC EYEWORM THELAZIA CALLIPAEDA
No full textINTRODUCTION: The establishment of arthropod colonies is an important tool to manipulate disease
vectors, investigate their life history traits, and their vector competence, prevention of vector borne
pathogen transmission, or to assess insecticidal/repellent activities. Some species of drosophilid flies
belonging to the genus Phortica (Phortica variegata and Phortica okadai) feed on ocular secretions of
mammals, acting as biological vectors of the zoonotic eyeworm Thelazia callipaeda (otranto et al.,
2005. Parasitology, 131: 847). recently, a third species, Phortica oldenbergi, has been experimentally
demonstrated as intermediate host of T. callipaeda. This study describes an effective breeding protocol
of Phortica variegata and Phortica oldenbergi in insectary conditions.
MATERIALS AND METHODS: Gravid flies of P. oldenbergi, P. variegata and Phortica semivirgo were
field collected in wooded areas of lazio region (Italy) (Pombi et al., 2020. Parasit vectors, 13: 1-9)
and allowed to oviposit singularly to obtain isofamilies. flies were maintained in ovipots (200ml) with
a plaster-covered bottom to maintain high humidity level inside. adult feeding was guaranteed by
freshly apple and a liquid dietary supplement (80% distilled water, 20% snail extract–based syrup and
0.009% sodium chloride), while larval development was obtained by two Drosophila-like agar feeding
media: a Standard one (86% water, 5.6% yeast, 3.9% sucrose, 0.5% agar, 3% cornmeal flour and
propionic acid) and another Chestnut flour-based (84.8% water, 6.69% yeast, 4.46% sucrose, 0.66%
agar, 2.67% chestnut flour, 0.66% banana, >0.001% propionic acid). all conditions were kept in a
climatic chamber with a photoperiod of 14:10h light: dark, 26±2°C and 80±10% rh.
RESULTS AND CONCLUSIONS: from 130 field collected Phortica spp. three generations (i.e., 783
f1, 109 f2, 6 f3) were obtained. Phortica oldenbergi was the species with higher breeding
performance, being the only species reaching f3, followed by P. variegata. Chestnut-based feeding
medium allowed higher adult production and survival probability in both P. oldenbergi and P. variegata.
adult production/female was promising in both species (P. oldenbergi: 13.5 f1/f; P. variegata: 4.5 f1/f;
Table), indicating the possibility to obtain stable colonies. This standardized breeding protocol, based
on controlled climatic parameters and fly densities, together with the introduction of an enriched feeding
medium, allowed to investigate aspects of life history traits of Phortica spp. involved in the transmission
of T. callipaeda. obtaining f3 generation of these species for the first time paved the road for the
establishment of stable colonies, an essential requirement for future studies on these vectors in
controlled conditions
Matriz de Pascal: aspectos teóricos e computacionais
No full textTrabalho de Conclusao de Curso - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Curso de Matemática
Laboratory breeding of two Phortica species (Diptera: Drosophilidae), vectors of the zoonotic eyeworm Thelazia callipaeda
No full textBackground: Some species of drosophilid flies belonging to the genus Phortica feed on ocular secretions of mammals, acting as biological vectors of the zoonotic eyeworm Thelazia callipaeda. This study describes an effective breeding protocol of Phortica variegata and Phortica oldenbergi in insectary conditions. Methods: Alive gravid flies of P. oldenbergi, P. variegata and Phortica semivirgo were field collected in wooded areas of Lazio region (Italy) and allowed to oviposit singularly to obtain isofamilies. Flies were maintained in ovipots (200 ml) with a plaster-covered bottom to maintain high humidity level inside. Adult feeding was guaranteed by fresh apples and a liquid dietary supplement containing sodium chloride and mucin proteins, while larval development was obtained by Drosophila-like agar feeding medium. The breeding performances of two media were compared: a standard one based on cornmeal flour and an enriched medium based on chestnut flour. All conditions were kept in a climatic chamber with a photoperiod of 14:10 h light:dark, 26 ± 2 °C and 80 ± 10% RH. Results: From a total of 130 field-collected Phortica spp., three generations (i.e. F1 = 783, F2 = 109, F3 = 6) were obtained. Phortica oldenbergi was the species with highest breeding performance, being the only species reaching F3. Chestnut-based feeding medium allowed higher adult production and survival probability in both P. oldenbergi and P. variegata. Adult production/female was promising in both species (P. oldenbergi: 13.5 F1/f; P. variegata: 4.5 F1/f). Conclusions: This standardized breeding protocol, based on controlled climatic parameters and fly densities, together with the introduction of an enriched chestnut-based feeding medium, allowed to investigate aspects of life history traits of Phortica spp. involved in the transmission of T. callipaeda. Obtaining F3 generation of these species for the first time paved the road for the establishment of stable colonies, an essential requirement for future studies on these vectors in controlled conditions. Graphical abstract: [Figure not available: see fulltext.]
- …
