86,615 research outputs found
Vettori dei giallumi della vite, fra vecchie conoscenze e nuove acquisizioni
No full textI giallumi della vite sono malattie associate a fitoplasmi segnalate per la prima volta in Italia all’inizio degli anni ’70 che si sono ampiamente diffuse, tanto da diventare un serio problema fitosanitario di rilevanza nazionale. Anche se molti agenti causali sono stati ritrovati in vite (Ca. Phytoplasma asteris, Ca. P. trifolii, Ca. P. fraxini) particolarmente dannosi sono il Ca. P. vitis agente della Flavescenza dorata (FD) nelle regioni centro settentrionali ed il Ca. P. solani agente del Legno nero (LN) con attacchi più localizzati ma diffusi in tutto il Paese. Recentemente in molte Regioni Italiane è stato osservato un aumento del numero di viti manifestanti sintomi ascrivibili ai giallumi. Le cause di questa recrudescenza possono essere molteplici ed ascrivibili ai cambiamenti dell’ambiente, degli ospiti vegetali, dei patogeni, degli insetti vettori o dei rapporti tra queste diverse componenti, nonché ad una minore efficacia degli insetticidi attualmente disponibili. Nel presente lavoro vengono trattate le attuali conoscenze sui vettori della FD e del LN per un loro efficace contenimento
The mosaic leafhopper Orientus ishidae: host plants, spatial distribution, infectivity, and transmission of 16SrV phytoplasmas to vines
No full textOrientus ishidae (Matsumura) is an Asian species introduced into Europe and recently associated with 16SrV phytoplasmas, related to grapevine “flavescence dorée”. Its life cycle, host plants, spatial distribution, infection and vector capability have been investigated in vine-growing areas of Piedmont, NW Italy. The spatial distribution of adults in vineyards was studied by applying interpolation methods to trap capture data. Insects were subject to molecular analyses to verify phytoplasma presence and identity. DNA extraction and PCR were made to detect 16SrV phytoplasmas. Transmission experiments were set up, using different sources for phytoplasma acquisition, and two plant species and an artificial diet for inoculation. Whole mount in situ hybridization was made to detect phytoplasmas in the salivary glands of adults. In the vineyard agro-ecosystem, 19 plant species (11 families), mainly broadleaf trees and shrubs, were recognized as host plants of the insect. Adults were more abundant on putative host plants than on grapevines, with a clear clustering at the edges of vineyards, and without a massive intrusion into the vineyard from outside. 16SrV phytoplasmas were detected only in adults captured with yellow sticky traps (20 out of 188 tested). The transmission of 16SrV phytoplasmas was successful after phytoplasma acquisition from infected broad bean and inoculation on grapevine
New insights in phytoplasma-vector interaction: acquisition and inoculation of Flavescence dorée phytoplasma by Scaphoideus titanus adults in a short window of time
No full textThe leafhopper Scaphoideus titanus is able to transmit 16SrV phytoplasmas agents of grapevine’s Flavescence dorée (FD) within 30-45 days, following an Acquisition Access Period (AAP) of a few days feeding on infected plants as a nymph, a Latency Period (LP) of 3-5 weeks becoming meanwhile an adult, and an Inoculation Access Period (IAP) of a few days on healthy plants. However, several aspects of FD epidemiology suggest how the whole transmission process may take less time, and may be start directly with adults of the insect vector. Transmission experiments have been set up under lab condition. Phytoplasma-free S. titanus adults were placed on broad bean (BB) plants (Vicia faba) infected by FD-C (16SrV-C) phytoplasmas for an AAP=7 days. Afterwards, they were immediately moved onto healthy BB for IAP, which were changed every 7 days, obtaining three timings of inoculation: IAP 1, IAP 2 and IAP 3, lasting 7, 14 and 21 days from the end of AAP, respectively. DNA was extracted from plants and insects, and PCR were performed to identify FD phytoplasmas. Insects were dissected and fluorescent in situ hybridization was made to detect the presence of phytoplasmas in midguts and salivary glands. The rate of infection in insects ranged 46-68% without significant differences among IAPs. Inoculation in plants succeeded in all IAPs, at a rate of 16-23% (no significant differences). Phytoplasma load was significantly higher in IAP3 than IAP 1-2 for both plants and insects
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
John F. Kennedy telegram to Roosevelt
No full textJersey Homesteads (later the Borough of Roosevelt) was established in the 1930s as an agro-industrial cooperative community. It was established specifically for urban Jewish garment workers, many of whom had emigrated from Europe. President John F. Kennedy sent a telegram to the citizens of Roosevelt, New Jersey, apologizing for not being able to attend the memorial dedication in honor of former President Franklin Delano Roosevelt. (Jersey Homesteads became Roosevelt in 1945 in honor of the president.) President Kennedy expressed his gratitude to the people of Roosevelt for constructing the memorial, and commented that it will serve as a constant reminder of Roosevelt's good works
Logarithmic variance profiles and the corresponding f-1 spectra of temperature fluctuations in turbulent Rayleigh-Bénard convection
No full textWe report experimental results for the temperature variance 2(z) and the corresponding frequency spectra P(f) in turbulent Rayleigh-Bénard convection (RBC) in a cylindrical sample of aspect ratioT= D/L = 1:00 (D = 1:12 m is the diameter and L = 1:12 m the height). The measurements were conducted in the Rayleigh-number range 1011 < Ra < 1:35 1014 and Pr ' 0:8. For Ra = 1:35x1014, 2(z) could be described well by a logarithmic dependence on the vertical position z in a range of z 1 < z < z 2 with z 1 ' 70 and z 2 = 0:1L. Here L=(2Nu) is the thickness of a thin thermal sublayer adjacent to the horizontal plate where the heat flux (denoted by the Nusselt number Nu) is carried mostly by thermal diffusion. In the log layer, we found that the temperature spectra had a significant frequency range over which P(f) f with close to 1. As Ra decreased, increased so that the log layer became thinner. At Ra = 2:05 1011, z 2 < z 1 and therefore there was no range for a log layer. Correspondingly, the temperature spectrum near the horizontal plate did not have the f1 scaling form either
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