12 research outputs found

    Eficiencia das maquinas no beneficiamento de sementes de trigo para remocao de sementes de aveia-preta.

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    O objetivo deste trabalho foi avaliar a eficiencia e eficacia da maquina-de-ar-e-peneiras e da mesa-de-gravidade na remocao de sementes de aveia-preta de lotes de sementes de trigo. Foram utilizados um lote de sementes de trigo, cultivar EMBRAPA-16, e sementes de aveia-preta, cultivar Comum. Na maquina-de-ar-e-peneiras foram utilizados quatro peneiras: 1,9x20; 2,0x20; 2,1x20 e 2,2 x 20mm, de furos oblongos na posicao da quarta peneira, e tres niveis de contaminacao: 5,10 e 15 sementes de aveia-preta para cada 100g de sementes de trigo. Os resultados permitiram concluir que: a) e possivel separar sementes de aveia-preta de lotes de sementes de trigo durante o beneficiamento; b) o uso da peneira 2,1 x 20 mm na maquina-de-ar-e-peneiras, independentemente do nivel de contaminacao, permite separar sementes de aveia-preta de sementes de trigo, colocando o lote dentro dos padroes minimos exigidos para a comercializacao; c) maquina-de-ar-e-peneiras seguida da mesa-de-gravidade retem integralmente as sementes de aveia-preta de lotes de sementes de trigo; d) o nivel de contaminacao inicial nao afeta a perda na sequencia maquina-de-ar-e-peneiras e mesa-de-gravidade.199

    Performance And Preference Of Broiler Chickens Exposed To Different Lighting Sources

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    Vision is important in poultry behavior and welfare. Poultry have highly specialized visual systems, and the majority of their behavior is mediated by vision. In the present study, we evaluated the lighting preference of broiler chickens exposed to different lighting sources and their production performance. In the first portion of the study, we evaluated the preference of birds for white and yellow lighting provided by light-emitting diode (LED) bulbs. Bird preference was assessed by videos recorded during the experiment. In the second portion of the study, we evaluated the performance of broiler chickens exposed to LED and compact fluorescent lamps (CFL). Performance was assessed in terms of mortality rate, bird BW, daily BW gain, feed consumption, and feed conversion. The chickens occupied environments with yellow and white LED lighting evenly and did not show any behavioral sign of preference for one of the environments. However, birds presented greater feed consumption at 21, 28, and 35 d of age when exposed to white LED lighting. Generally, birds exposed to LED lighting presented better production performance than birds under the CFL. Seven-day-old male chickens presented better feed conversion under LED illumination than did males of the same age under CFL. © Poultry Science Association, Inc.2216270Olanrewaju, H.A., Thaxton, J.P., Dozier, W.A., Purswell, J., Roush, W.B., Branton, S.L., A review of lighting programs for broiler production (2006) Int. J. Poult. Sci, 5, pp. 301-308Théry, M., Forest light and its influence on habitat selection (2001) Plant Ecol, 153, pp. 251-261Prescott, N.B., Wathes, C.M., Reflective properties of domestic fowl (Gallus g. domesticus), the fabric of their housing and the characteristics of the light environment in environmentally controlled poultry houses (1999) Br. Poult. Sci, 40, pp. 185-193(1992) Report On the Welfare of Broiler Chickens, , Farm Animal Welfare Council, Ministry of Agriculture, Fisheries and Food, London, UKLewis, P.D., Morris, T., (2006) Poultry Lighting- the Theory and Practice, , Nottingham Univ. Press, Nottingham, UKDavis, N.J., Prescott, N.B., Savory, C.J., Wathes, C.M., Preferences of growing fowls for different light intensities in relation to age, strain and behaviour (1999) Anim. Welf, 8, pp. 193-203Widowski, T.M., Keeling, L.J., Duncan, I.J.H., The preferences of hens for compact fluorescent over incandescent lighting (1992) Can. J. Anim. Sci, 72, pp. 203-211Vandenberg, C., Widowski, T.M., Hens' preferences for high-intensity high-pressure sodium or lowintensity incandescent lighting (2000) J. Appl. Poult. Res, 9, pp. 172-178Prayitno, D.S., Phillips, C.J.C., Omed, H., The effects of color of lighting on the behavior and production of meat chickens (1997) Poult. Sci, 76, pp. 452-457Widowski, T.M., Duncan, I.J.H., Laying hens do not have a preference for high-frequency versus low-frequency compact fluorescent light sources (1996) Can. J. Anim. Sci, 76, pp. 177-181Prescott, N.B., Wathes, C.M., Jarvis, J.R., Light, vision and the welfare of poultry (2003) Anim. Welf, 12, pp. 269-288Sherwin, C.M., Light intensity preferences of domestic male turkeys (1998) Appl. Anim. Behav. Sci, 58, pp. 121-130Denbow, D.M., Leighton, A.T., Hulet, R.M., Effect of light sources and light intensity on growth, performance, and behaviour of female turkeys (1990) Br. Poult. Sci, 31, pp. 439-443Boshouwers, F.M.G., Nicaise, E., Artificial light sources and their influences on physical activity and energy expenditure of laying hens (1993) Br. Poult. Sci, 34, pp. 11-19Duncan, I.J.H., Designing environments for animals-Not for public perceptions (1992) Br. Vet. J, 148, pp. 475-477Dawkins, M.S., From an animal's point of view: Motivation, fitness, and animal welfare (1990) Behav. Brain Sci, 13, pp. 1-61(2010) Guide For the Care and Use of Agricultural Animals In Research and Teaching, , Federation of Animal Science Societies, Fed. Anim. Sci. Soc, Champaign, ILPluma Agroavícola, Linha Santo Izidoro, Dois Vizinhos, Paranå State, BrazilBizeray, D., Estevez, I., Leterrier, C., Faure, F.M., Effects of increasing environmental complexity on the physical activity of broiler chickens (2002) Appl. Anim. Behav. Sci, 79, pp. 27-41Estevez, I., Keeling, L.J., Newberry, R.C., Decreasing aggression with increasing group size in young domestic fowl (2003) Appl. Anim. Behav. Sci, 84, pp. 213-218Zonta, E.P., Machado, A.A., (1984) SANEST-Sistema De Anålise Estatística Para Microcomputadores, , Universidade Federal de Pelotas, Pelotas, BrazilMiragliotta, M.Y., (2005) Avaliação Das CondiçÔes Do Ambiente Interno Em Dois GalpÔes De Produção Comercial De Frangos De Corte, Com Ventilação E Densidade Populacional Diferenciados, , PhD Diss. State Univ. of Campinas, Campinas, São Paulo, BrazilNuboer, J.F.W., Coemans, M.A.J.M., Vos, J.J., Artificial lighting in poultry houses: Are photometric units appropriate for describing illumination intensities (1992) Br. Poult. Sci, 33, pp. 135-140Kristensen, H.H., Prescott, N.B., Perry, G.C., Ladewig, J., ErsbÞll, A.K., Overvad, K.C., Wathes, C.M., The behaviour of broiler chickens in different light sources and illuminances (2007) Appl. Anim. Behav. Sci, 103, pp. 75-89Prayitno, D.S., Phillips, C.J.C., Omed, H.M., The initial and long-term preference of broilers for red, blue, or green light after being reared in red, blue, green, or white light (1993) Anim. Prod, 56, pp. 438-445Goldflus, F., (1994) Viabilidade Da Criação De Frangos De Corte Sob Alta Densidade Populacional, , MS Thesis. College of Agrarian Sciences and Veterinary, Paulista State Univ, Jaboticabal, São Paulo, BrazilYahav, S., Hurwitz, S., Rozenboim, I., The effect of light intensity on growth and development of turkey toms (2000) Br. Poult. Sci, 41, pp. 101-106Deep, A., Schwean-Lardnera, K., Croweb, T.G., Fancherc, B.I., Classena, H.L., Effect of light intensity on broiler behaviour and diurnal rhythms (2012) Appl. Anim. Behav. Sci, 136, pp. 50-56Downs, K.M., Lien, R.J., Hess, J.B., Bilgili, S.F., Dozier, W.A., The effects of photoperiod length, light intensity, and feed energy on growth responses and meat yield of broilers (2006) J. Appl. Poult. Res, 15, pp. 406-416Rozenboim, I., Biran, I., Chaiseha, Y., Yahav, S., Rosenstrauch, A., Sklan, D., Halevy, O., The effect of a green and blue monochromatic light combination on broiler growth and development (2004) Poult. Sci, 83, pp. 842-84

    A Fermi gamma-ray burst monitor search for electromagnetic signals coincident with gravitational-wave candidates in Advanced LIGO's first observing run

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    We present a search for prompt gamma-ray counterparts to compact binary coalescence gravitational wave (GW) candidates from Advanced LIGO's first observing run (O1). As demonstrated by the multimessenger observations of GW170817/GRB 170817A, electromagnetic and GW observations provide complementary information about the astrophysical source, and in the case of weaker candidates, may strengthen the case for an astrophysical origin. Here we investigate low-significance GW candidates from the O1 compact binary coalescence searches using the Fermi Gamma-Ray Burst Monitor (GBM), leveraging its all sky and broad energy coverage. Candidates are ranked and compared to background to measure the significance. Those with false alarm rates (FARs) of less than 10−5 Hz (about one per day, yielding a total of 81 candidates) are used as the search sample for gamma-ray follow-up. No GW candidates were found to be coincident with gamma-ray transients independently identified by blind searches of the GBM data. In addition, GW candidate event times were followed up by a separate targeted search of GBM data. Among the resulting GBM events, the two with the lowest FARs were the gamma-ray transient GW150914-GBM presented in Connaughton et al. and a solar flare in chance coincidence with a GW candidate

    XIPE

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    XIPE, the X-ray Imaging Polarimetry Explorer, is a mission dedicated to X-ray Astronomy. At the time of writing XIPE is in a competitive phase A as fourth medium size mission of ESA (M4). It promises to reopen the polarimetry window in high energy Astrophysics after more than 4 decades thanks to a detector that efficiently exploits the photoelectric effect and to X-ray optics with large effective area. XIPE uniqueness is time-spectrally-spatially-resolved X-ray polarimetry as a breakthrough in high energy astrophysics and fundamental physics. Indeed the payload consists of three Gas Pixel Detectors at the focus of three X-ray optics with a total effective area larger than one XMM mirror but with a low weight. The payload is compatible with the fairing of the Vega launcher. XIPE is designed as an observatory for X-ray astronomers with 75 % of the time dedicated to a Guest Observer competitive program and it is organized as a consortium across Europe with main contributions from Italy, Germany, Spain, United Kingdom, Poland, Sweden.Peer reviewe

    Multi-messenger Observations of a Binary Neutron Star Merger

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    International audienceOn 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∌1.7 s\sim 1.7\,{\rm{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg(2) at a luminosity distance of 40−8+8{40}_{-8}^{+8} Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26  M⊙\,{M}_{\odot }. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∌40 Mpc\sim 40\,{\rm{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∌10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∌9\sim 9 and ∌16\sim 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
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