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Aspectos da biologia e morfologia da broca do pedúnculo floral do coqueiro, Homalinotus coriaceus (Gyllenhal) (Coleoptera: Curculionidae)

Sarro, Fernanda B.; Crocomo, Wilson B.; Ferreira, Joana M.S.
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: 7-12
POR
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16.07%
A broca do pedúnculo floral do coqueiro, Homalinotus coriaceus (Gyllenhal), é uma praga limitante à produção de coco no Brasil, provocando a queda das flores e dos frutos imaturos. Sua biologia é pouco conhecida o que tem dificultado a seu manejo adequado no campo. Dessa forma, foi realizado o estudo da biologia desse inseto no Laboratório de Entomologia da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Tabuleiros Costeiros - CPATC, em Aracaju, SE, à temperatura de 25 ± 2°C, umidade relativa de 70% e fotofase de 12h. Para alimentação e oviposição dos adultos coletados no campo foram utilizados toletes de cana-de-açúcar como substrato, nos quais as fêmeas colocaram ovos individualizados, cujo período de incubação variou de seis a 14 dias. As larvas foram criadas no mesocarpo de coco, desenvolvendo-se em 144 dias em média, passando por cinco a sete ínstares. O período pupal médio foi de 31 dias. A longevidade do adulto variou de 303 a 695 dias para fêmeas e de 246 a 635 dias para machos, sendo o ciclo de ovo a adulto de 181,9 dias para fêmeas e 188,5 para machos. Foram observadas diferenças morfológicas nas pupas e nos adultos, que podem ser utilizadas para separação dos sexos. Ao contrário dos machos...

Protection of Dates from Injury Caused by the Apache Cicada in California

Elmer, H. S.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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26.24%
The Apache cicada, Diceroprocta apache (Davis), prior to 1961 was not an economically important pest of dates. Loss of a high percentage of the date crop during 1961 in one area of southern California was directly attributed to the oviposition habits of this cicada. Date strands are used as one of the types of sites for egg laying, and under certain conditions oviposition punctures girdle and obstruct the flow of sap in the strand, causing the dates to shrivel, dry up, and fall to the ground. Paper bunch covers, normally used by growers to protect ripening dates from rain and birds, were placed over the bunches prior to initial oviposition in a series of tests. These covers gave complete protection from cicada-induced fruit loss.

Mild chilling injury of banana (Cavendish cv. Williams) and its control in the field.

Harvey, Bradley Voules
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2006
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47.21%
Chilling injury in banana fruit is caused by prolonged exposure to temperatures less than 13°C. This can occur during bunch development in the field or postharvest handling and storage. Mild symptoms of chilling injury are localised to peel tissue and reduce visual quality of fruit. Light microscopy was used in the present study to analyse symptoms of mild chilling injury in Cavendish cv. Williams banana. Following storage at 5°C for 24hours, symptoms of chilling injury in the form of brown discolouration was observed within laticifers in sub-epidermal peel tissue. Browning was not observed in other vascular tissues as previous research has suggested. Causal mechanisms associated with browning of latex within laticifers were investigated. Polyphenol oxidase (PPO) activity in fractions of banana peel latex was measured and found to be highest in the lutoid fraction. PPO activity also provided indirect evidence that phenolics were present in peel latex. Literature suggests possible compartmentalisation of PPO and phenolics in banana lutoids. In this study it is suggested that PPO and phenolics associated with lutoids in banana peel latex may be involved in browning due to chilling stress. The lipid content of lutoids from banana latex was also investigated using FTIR spectroscopy...

Beam Dynamics in High Intensity Cyclotrons Including Neighboring Bunch Effects: Model, Implementation and Application

Yang, J. J.; Adelmann, A.; Humbel, M.; Seidel, M.; Zhang, T. J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/03/2010
Relevância na Pesquisa
26.29%
Space charge effects, being one of the most significant collective effects, play an important role in high intensity cyclotrons. However, for cyclotrons with small turn separation, other existing effects are of equal importance. Interactions of radially neighboring bunches are also present, but their combined effects has not yet been investigated in any great detail. In this paper, a new particle in cell based self-consistent numerical simulation model is presented for the first time. The model covers neighboring bunch effects and is implemented in the three-dimensional object-oriented parallel code OPAL-cycl, a flavor of the OPAL framework. We discuss this model together with its implementation and validation. Simulation results are presented from the PSI 590 MeV Ring Cyclotron in the context of the ongoing high intensity upgrade program, which aims to provide a beam power of 1.8 MW (CW) at the target destination.

Silicon detectors for the n-TOF neutron beams monitoring

Cosentino, L.; Musumarra, A.; Barbagallo, M.; Colonna, N.; Damone, L.; Pappalardo, A.; Piscopo, M.; Finocchiaro, P.; collaboration, for the n-TOF
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/06/2015
Relevância na Pesquisa
16.07%
During 2014 the second experimental area EAR2 was completed at the n-TOF neutron beam facility at CERN. As the neutrons are produced via spallation, by means of a high-intensity 20 GeV pulsed proton beam impinging on a thick target, the resulting neutron beam covers an enormous energy range, from thermal to several GeV. In this paper we describe two beam diagnostic devices, designed and built at INFN-LNS, both exploiting silicon detectors coupled with neutron converter foils containing 6Li. The first one is based on four silicon pads and allows to monitor the neutron beam flux as a function of the neutron energy. The second one, based on position sensitive silicon detectors, is intended for the reconstruction of the beam profile, again as a function of the neutron energy. Several electronic setups have been explored in order to overcome the issues related to the gamma flash, namely a huge pulse present at the start of each neutron bunch which may blind the detectors for some time. The two devices have been characterized with radioactive sources at INFN-LNS and then tested at n-TOF. The wide energy and intensity range they proved capable of sustaining, made them quite attractive and suitable to be used in both EAR1 and EAR2 n-TOF experimental areas...

Halo Formation in Spheroidal Bunches with Self-Consistent Stationary Distributions

Fedotov, A. V.; Gluckstern, R. L.; Kurennoy, S. S.; Ryne, R. D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/07/1998
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A new class of self-consistent 6-D phase space stationary distributions is constructed both analytically and numerically. The beam is then mismatched longitudinally and/or transversely, and we explore the beam stability and halo formation for the case of 3-D axisymmetric beam bunches using particle-in-cell simulations. We concentrate on beams with bunch length-to-width ratios varying from 1 to 5, which covers the typical range of the APT linac parameters. We find that the longitudinal halo forms first for comparable longitudinal and transverse mismatches. An interesting coupling phenomenon - a longitudinal or transverse halo is observed even for very small mismatches if the mismatch in the other plane is large - is discovered.; Comment: 3 pages, 3 figures; presented at European Particle Accelerator Conference, Stockholm, Sweden (June 22-26, 1998)

Possible operation of the European XFEL with ultra-low emittance beams

Brinkmann, R.; Schneidmiller, E. A.; Yurkov, M. V.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/01/2010
Relevância na Pesquisa
16.29%
Recent successful lasing of the Linac Coherent Light Source (LCLS) in the hard x-ray regime and the experimental demonstration of a possibility to produce low-charge bunches with ultra-small normalized emittance have lead to the discussions on optimistic scenarios of operation of the European XFEL. In this paper we consider new options that make use of low-emittance beams, a relatively high beam energy, tunable-gap undulators, and a multi-bunch capability of this facility. We study the possibility of operation of a spontaneous radiator (combining two of them, U1 and U2, in one beamline) in the SASE mode in the designed photon energy range 20-90 keV and show that it becomes possible with ultra-low emittance electron beams similar to those generated in LCLS. As an additional attractive option we consider the generation of powerful soft x-ray and VUV radiation by the same electron bunch for pump-probe experiments, making use of recently invented compact afterburner scheme. We also propose a betatron switcher as a simple, cheap, and robust solution for multi-color operation of SASE1 and SASE2 undulators, allowing to generate 2 to 5 x-ray beams of different independent colors from each of these undulators for simultaneous multi-user operation. We describe a scheme for pump-probe experiments...