3,490 research outputs found
Editorial: Biofuels and Bioproducts From Anaerobic Processes: Anaerobic Membrane Bioreactors (AnMBRs)
New biodegradable waste treatment configurations and technologies have arisen to support the transition of treatment plants toward resource recovery facilities. The interest in Anaerobic Membrane Biological Reactor (AnMBR) technology is increasing due to the advantages related to combine anaerobic digestion with membrane filtration. Thanks to the complete retention of anaerobic microorganisms, AnMBRs have the capacity to efficiently recover most of the energy potential in biodegradable waste streams in the form of biogas and produce high-quality effluents with low biomass production
Control of Hyalesthes obsoletus nymphs based on chemical weeding and insecticides applied on Urtica dioica
Bois noir is a grapevine yellows disease associated with Candidatus Phytoplasma solani and transmitted to grapevines by means of the planthopper Hyalesthes obsoletus Signoret (Homoptera, Cixiidae). The overwintering nymphs of the vector acquire the phytoplasma feeding on roots of herbaceous plants, including Urtica dioica L. (stinging nettle). In German and Italian vineyards the possibility to control the H. obsoletus nymphs feeding on stinging nettle roots using chemical weeding and insecticides was investigated. In particular, the effect of herbicides, applied in autumn and in different spring timings, and neonicotinoid insecticides on vector adult emergence was evaluated. Trials conducted to control nettle with glyphosate or a mixture of glyphosate+flazasulfuron significantly reduced the density of emerging adult vectors. The efficacy of herbicides was highest when they were applied in autumn or in early spring with the nymphs not older than the fourth instar. Herbicides applied too close to the beginning of the emergence of adults reduced numbers only during the late part of the planthopper flight-period. Although neonicotinoid insecticides applied in early spring gave efficacy comparable to herbicides, their use is not advisable for the negative side effects on non-target arthropods (e.g. honeybees). Overall, the combination of cultural practices and accurately timed applications of selective herbicides might help to refine the current Integrated Pest Management recommendations for controlling nettle, H. obsoletus and consequently bois noir.
Side effects of sulfur dust on the European grapevine moth Lobesia botrana and the predatory mite Kampimodromus aberrans in vineyards
To reduce the impact of synthetic insecticides on human health and the environment, eco-friendly alternatives must be investigated. Knowledge of the side effects on pests and natural enemies of natural products applied to vineyards is very useful. Sulfur dust, which is used in vineyards to control powdery mildew, is investigated in laboratory and field bioassays for its effects on Lobesia botrana egg laying, egg hatching, and larval settlement. In field trials, the efficacy of sulfur dust against the two L. botrana carpophagous generations is compared with that of Bacillus thuringiensis and kaolin, and its side effects on the phytoseiid mite Kampimodromus aberrans are evaluated. In the bioassays, sulfur dust reduced female survival by 43%, egg laying by around 80%, egg hatching by 10%, and larval settlement by 55%. In field trials, sulfur dust caused a significant decrease in the number of L. botrana larval nests of both generations, even though the efficacy was lower than that of B. thuringiensis. No negative effects of sulfur dust on the predatory mite population density was observed. On the basis of these results, in the context of Integrated Pest Management strategies in vineyards, the activity of sulfur dust against L. botrana could be exploited by timing its application to the beginning of egg laying
Generation of pseudo-random sequences for noise radar applications
Noise Radar Technology (NRT) is nowadays a promising tool in radar systems. It is based on the transmission of waveforms composed of many noisy samples, which behave as LPI (Low Probability of Intercept) and antispoofing signals. Each noisy sequence is theoretically uncorrelated with the others. In the paper we propose a scheme to generate a “tailored” pseudo-random sequences (limited in amplitude). It will be followed by an analysis of the main performances in terms of the Peak Side Lobe Ratio (PSLR) of the autocorrelation function, cross-correlation analysis to evaluate the orthogonality, bandwidth and energy efficiency
Side Effects of Kaolin and Bunch-Zone Leaf Removal on Generalist Predators in Vineyards
In vineyards, kaolin application and bunch-zone leaf removal (LR) were effective in the control of leafhoppers and Lobesia botrana, but their side effects on generalist predators are still poorly understood. In north-eastern Italian vineyards, the impact of kaolin and LR on species and functional diversity of spiders, as well as the abundance of spiders and generalist predatory insects, was assessed in one vineyard for two consecutive years and in two vineyards for one year. The ecological indices of the spider community were never influenced by kaolin and only in one case were they influenced by LR. At the spider family level, kaolin reduced the abundance of Araneidae, Oxypidae and Salticidae, but only in single cases. In single cases, kaolin reduced the amount of Orius sp. anthocorids and increased that of Scymninae coccinellids, whereas LR increased the amount of Aeolothrips sp. The moderate use of kaolin and the application of LR had negligible and inconsistent impacts on generalist predatory arthropods in vineyards and were therefore, compatible with IPM strategies
Interpreting the recent results on direct search for dark matter particles in terms of relic neutralino
The most recent results from direct searches for dark matter particles in the
galactic halo are examined in terms of an effective Minimal Supersymmetric
extension of the Standard Model at the electroweak scale without gaugino masses
unification. We show that the annual modulation effect at 8.2 C.L.
recently presented by the DAMA Collaboration, as the result of a combined
analysis of the DAMA/NaI and the DAMA/LIBRA experiments for a total exposure of
0.82 ton yr, fits remarkably well with what expected for relic neutralinos for
a wide variety of WIMP distribution functions. Bounds derivable from other
measurements of direct searches for dark matter particles are analyzed. We
stress the role played by the uncertainties affecting the neutralino--quark
couplings arising from the involved hadronic quantities. We also examine how
present data on cosmic antiprotons can help in constraining the neutralino
configurations selected by the DAMA effect, in connection with the values of
the astrophysical parameters.
Perspectives for measurement of antideuterons possibly produced in the
galactic halo by self--annihilation of neutralinos belonging to the DAMA
configurations are examined. Finally, we discuss how findings at LHC would
impact on these issues.Comment: 18 pages, 10 figures a few minor comments and two references adde
Behavioural Evidence and Chemical Identification of a Female Sex Pheromone in Anagrus atomus (Hymenoptera: Mymaridae)
Anagrus atomus (L.) is an egg parasitoid involved in the biological control of Empoasca vitis (G\uf6the) in vineyards. Sex pheromones play a crucial role in mate finding for several parasitoid species and could be used for monitoring under field conditions. We carried out laboratory and field studies aimed at assessing the existence and identity of a possible A. atomus sex pheromone. We found that males were significantly attracted by virgin females independent of age. Males were not attracted to individuals of the same sex, but they were attracted by a crude extract from an unmated female and its polar fraction. Eugenol (4-allyl-2-methoxyphenol) was identified as the attractive substance and proved to be attractive not only in the olfactometer but also in another laboratory bioassay and under field conditions. Attraction of males, but not females, confirms that this is not an aggregation pheromone. This is the first sex-pheromone component identified in Mymaridae, however more compounds could be involved in the mating behaviour of A. atomus. The utility of a sex pheromone in A. atomus is discussed in the context of fitness returns
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