205 research outputs found
Sull'antagonismo in vivo ed in vitro di Acremonium byssoides, endofita in Vitis vinifera, nei confronti di Plasmopara viticola
Lo studio dell\u2019interazione fra Acremonium byssoides, Vitis vinifera e
Plasmopara viticola, condotto nell\u2019ultimo decennio, ha evidenziato in vitro e in vivo
l\u2019attivit\ue0 antagonistica dell\u2019ifomicete, endofita negli organi verdi di alcune cultivars
di vite, nei confronti del patogeno. In particolare, \ue8 stato accertato che sospensioni
conidiche, filtrati colturali, estratti grezzi e metaboliti di A. byssoides riducono
sensibilmente la germinazione delle spore agamiche e gamiche di P. viticola, limitando
la produzione di propaguli. Inoltre, l\u2019uso di un microscopio laser confocale e l\u2019impiego
di un\u2019opportuna tecnica di decolorazione dei tessuti fogliari, seguita da colorazione
di contrasto, ha consentito di visualizzare l\u2019ifomicete, latente nelle nervature di
foglie sane e iperparassita dell\u2019oomicete in foglie infette. In queste ultime, infatti, A.
byssoides, dopo aver prodotto metaboliti secondari tossici per P. viticola, ne invade e
degrada micelio, rami sporangiofori e spore gamiche.
Tale attivit\ue0 antagonistica, determinando il contenimento sia della diffusione
che della sopravvivenza del patogeno, pu\uf2 assumere, quindi, un ruolo rilevante nella
definizione di strategie di difesa biologica contro la peronospora della vite
Assessing accessibility and safety conditions in an urban environment: what do pedestrians perceive?
Propuesta de tecnología móvil para la administración de información vinculada a la gestión de espacios áulicos
El avance de la informatización en las actividades humanas es un hecho, en las últimas décadas se ha incrementado la cantidad de software producido reflejándose en cambios en diversos aspectos de la sociedad del conocimiento. El ámbito educativo no escapa a esta realidad. Por lo expuesto, en este trabajo se presenta una segunda versión de un sistema web para la administración de espacios áulicos; incorporándose como tecnología emergente el acceso a información desde dispositivos móviles. El prototipo fue modelizado a partir de la gestión de espacios físicos de la Facultad de Ciencias Exactas y Naturales y Agrimensura (FaCENA) – Sede 9 de Julio, de la Universidad Nacional del Nordeste (UNNE), con miras a adecuarse a otras instituciones de Educación Superior.V Workshop innovación en sistemas de softwareRed de Universidades con Carreras en Informática (RedUNCI
The Mechanisms of Codon Reassignments in Mitochondrial Genetic Codes
Many cases of non-standard genetic codes are known in mitochondrial genomes.
We carry out analysis of phylogeny and codon usage of organisms for which the
complete mitochondrial genome is available, and we determine the most likely
mechanism for codon reassignment in each case. Reassignment events can be
classified according to the gain-loss framework. The gain represents the
appearance of a new tRNA for the reassigned codon or the change of an existing
tRNA such that it gains the ability to pair with the codon. The loss represents
the deletion of a tRNA or the change in a tRNA so that it no longer translates
the codon. One possible mechanism is Codon Disappearance, where the codon
disappears from the genome prior to the gain and loss events. In the
alternative mechanisms the codon does not disappear. In the Unassigned Codon
mechanism, the loss occurs first, whereas in the Ambiguous Intermediate
mechanism, the gain occurs first. Codon usage analysis gives clear evidence of
cases where the codon disappeared at the point of the reassignment and also
cases where it did not disappear. Codon disappearance is the probable
explanation for stop to sense reassignments and a small number of reassignments
of sense codons. However, the majority of sense to sense reassignments cannot
be explained by codon disappearance. In the latter cases, by analysis of the
presence or absence of tRNAs in the genome and of the changes in tRNA
sequences, it is sometimes possible to distinguish between the Unassigned Codon
and Ambiguous Intermediate mechanisms. We emphasize that not all reassignments
follow the same scenario and that it is necessary to consider the details of
each case carefully.Comment: 53 pages (45 pages, including 4 figures + 8 pages of supplementary
information). To appear in J.Mol.Evo
Improvement of Fresh Ovine “Tuma” Cheese Quality Characteristics by Application of Oregano Essential Oils
In the present work, oregano essential oils (OEOs) were applied to process the fresh ovine cheese "Tuma" obtained by pressed cheese technology. Cheese making trials were performed under industrial conditions using ewe's pasteurized milk and two strains of Lactococcus lactis (NT1 and NT5) as fermenting agents. Two experimental cheese products (ECP) were obtained through the addition of 100 (ECP100) and 200 (ECP200) & mu;L/L of OEO to milk, while the control cheese product (CCP) was OEO-free. Both Lc. lactis strains showed in vitro and in vivo ability to grow in the presence of OEOs and to dominate over indigenous milk lactic acid bacteria (LAB) resistant to pasteurization. In the presence of OEOs, the most abundant compound found in cheese was carvacrol, constituting more than 65% of the volatile fraction in both experimental products. The addition of OEOs did not influence ash, fat, or protein content, but it increased by 43% the antioxidant capacity of the experimental cheeses. ECP100 cheeses showed the best appreciation scores by the sensory panel. In order to investigate the ability OEOs to be used as a natural preservative, a test of artificial contamination was carried out, and the results showed a significant reduction of the main dairy pathogens in OEO-added cheeses
Neutrinos Angra experiment: commissioning and first operational measurements
The Neutrinos Angra Experiment has completed a major step by finishing the
comissioning of the detector and the data acquisition system at the
experimental site located in the Angra dos Reis nuclear power plant. The
experiment consists of a water-based detector and associated electronics, both
designed with the goal of detecting the electron antineutrinos produced by the
nuclear reactor. The detection is possible due to the Inverse Beta Decay, where
the final products in the water are photons in the UV-to-visible range of the
spectrum. The assembled detector comprises three active volumes filled with
water: (i) a cubic target detector for electron antineutrinos, covered by 32
8-inches PMTs, (ii) a lateral layer surrounding the target (veto) equipped with
4 PMTs and (iii) a third volume covering the top of both, also equipped with
4~PMTs. In the present document the main features of the detector assembly as
well as the integration of the readout electronics on-site are reported.
Finally, some operational characteristics are shown based on straightforward
analysis of the first measurements performed during the last months with the
fully working detector
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