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31.
Experiments of accelerated oxidation of "fino" sherry wines have been conducted at 25 degrees C and under the influence of UV-visible radiation (a xenon lamp of 1500 W). With the aim of determining the contribution of UV-vis radiation to the browning phenomenon, two types of glass bottles were employed: topaz bottles (with low values of transmittance in the UV-visible range) and transparent bottles. To identify significant differences between the wine before and after being subjected to the influence of the UV-vis radiation, the values of absorbance at 420 nm and the concentrations of various polyphenolic and volatile compounds were submitted to a multivariate variance analysis. Both factors considered (time and type of bottle) had a statistically significant effect on the values of absorbance at 420 nm and on the concentration of most of the polyphenolic compounds, whereas only the "time" factor was significant for volatile compounds. All wines showed losses in several polyphenolic compounds, which were more severe for the wines bottled in transparent glasses. However, these wines exhibited a lower degree of visual browning (abs 420 nm). In the case of volatile compounds, most of these presented increases during storage exposed to the influence of the UV-vis radiation.  相似文献   
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Many studies have confirmed the validity of plant cover and organic farming in ameliorating soil quality. The goal of this study was to investigate the efficiency of rehabilitation practices in a degraded soil ecosystem consisting of: (i) organic or inorganic fertilization; and (ii) presence or absence of almond trees. The experiments were carried out for 2 years in the South of Italy in three fields characterized by different slope (0%, 2%, and 6%). Each field was split up into two parts, one assigned to organic fertilization and the other assigned to mineral fertilization, and planted with almond trees using GF677 or Franco rootstocks. The results showed that the organic fertilization, particularly in the presence of the Franco rootstock, resulted more effective in increasing soil organic matter content and microbial activity especially in the 0% and 2% slopes. However, in the 6% slope, where a lower soil metabolism was observed, an improvement of chemical and biochemical soil properties was generally evident for both fertilization systems. The Franco rootstock improved soil quality and maintaining a good production, whereas the GF677 has exploited more soil resources, resulting in a higher growth and yield; therefore, the use of almond tree with Franco rootstock associated with organic matter application is a useful practice in order to preserve soil quality and to rehabilitate degraded soils. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Journal of Plant Diseases and Protection - Pepino mosaic virus (PepMV) disease causes important losses in tomato (Solanum lycopersicum) yield around the world. In order to find new sources of...  相似文献   
34.

Whiteflies are sap-sucking insects responsible for high economic losses. They colonize hundreds of plant species and cause direct feeding damage and indirect damage through transmission of devastating viruses. Modern agriculture has seen a history of invasive whitefly species and populations that expand to novel regions, bringing along fierce viruses. Control efforts are hindered by fast virus transmission, insecticide-resistant populations, and a wide host range which permits large natural reservoirs for whiteflies. Augmentative biocontrol by parasitoids while effective in suppressing high population densities in greenhouses falls short when it comes to preventing virus transmission and is ineffective in the open field. A potential source of much needed novel control strategies lays within a diverse community of whitefly endosymbionts. The idea to exploit endosymbionts for whitefly control is as old as identification of these bacteria, yet it still has not come to fruition. We review where our knowledge stands on the aspects of whitefly endosymbiont evolution, biology, metabolism, multitrophic interactions, and population dynamics. We show how these insights are bringing us closer to the goal of better integrated pest management strategies. Combining most up to date understanding of whitefly–endosymbiont interactions and recent technological advances, we discuss possibilities of disrupting and manipulating whitefly endosymbionts, as well as using them for pest control.

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OBJECTIVE: To determine bone healing at 20 weeks, after either static fixation (SG) or after dynamization (DG) at 4 weeks in osteotomized canine femurs repaired with an interlocking nail (ILN) secured with a type I external skeletal fixator (ESF). STUDY DESIGN: Experimental study. ANIMALS: Ten adult beagle dogs. METHODS: After mid-diaphyseal femoral osteotomy, femurs in 10 dogs were repaired with an ILN secured with 4 (2 proximal, 2 distal) threaded custom pins (TP; 2.7-mm-diameter cortical screw with a 2-mm shaft attached to the screw head) to which 2 parallel connecting bars were attached in a type I ESF configuration. In 5 dogs, dynamization was performed at 4 weeks by removing the connecting bars and 2 distal screws. Limb function, range of motion of the stifle joint (ROMSJ), radiographic evidence of bone healing, and complications were studied for 20 weeks. RESULTS: Full limb function was achieved between 8 and 10 weeks in SG dogs, but a decreased ROMSJ was observed from 5 to 8 weeks. In DG dogs, full limb function occurred between 5 and 6 weeks except in 1 dog, and ROMSJ was considered normal in all dogs. Bone healing was not affected by dynamization. Average healing time for SG was 12.8 weeks, and for DG it was 13.6 weeks. Periosteal reaction at TP insertion points, osteolysis around the thread and head of TPs were observed in both groups. A windshield-wiper effect was observed at the tip of 1 ILN. CONCLUSION: ILN locked with a type I ESF can be used for fixation of mid-shaft femoral fractures. Dynamization at 4 weeks did not affect bone healing but did prevent stifle ankylosis and promoted earlier limb function. CLINICAL RELEVANCE: ILN locked with a type I ESF is seemingly a feasible method for repair of mid-shaft femoral fractures and may decrease risk of nail failure.  相似文献   
37.
Sesame seeds are an excellent food and non-food raw material, for which there is a consolidated deficit in Italy and in other European Union countries. For this reason, a 2-years experiment was conducted in Sicily to compare the agronomic performance (phenology, morphological and productive traits) and grain quality (oil and its main constituents, protein of defatted flour, fibre) of three landraces, one of Turkish origin and two Sicilian (“Ispica” and “Modica”), and two improved varieties (‘Pachequino’ and ‘Yori 77’). The landraces evidenced earliness (115 days) and the greater height of insertion of first capsule (0.52 m), whereas the variety ‘Pachequino’ was the most productive (3.5 t ha?1). Turkish and “Ispica” landraces and ‘Yori 77’ variety provided seeds with greater lipid (54 %, on average) and protein contents (44 % on defatted flour, on average). ‘Pachequino’ and both Sicilian landraces produced seeds richer in fibre fractions. As regard to oil quality, the oleic acid/linoleic acid was found balanced (about 1) for Turkish landrace, and it decreased for the other cultivars reaching the lowest value for ‘Pachequino’. “Modica” had higher quantity of unsaponifiable matter (1.98 %) in the oil, whereas ‘Yori 77’ had the maximum concentration of phytosterols (5532.8 mg kg?1). Policosanol fraction prevailed in oil of “Ispica” (205.8 mg kg?1). Moreover, there was variability in the fatty acid, sterol and policosanol compositions with differences among the cultivars. Research provide information to exploit sesame within agrosystems under Mediterranean climates, and may be a starting point for breeding activity to enhance crop productivity and grain quality.  相似文献   
38.
Changes in soil properties related to natural regeneration of silver fir (Abies alba, Mill.) in small (185 m2) and medium (410 m2) gaps, in the Calabria Apennines (Southern Italy), were studied 2 years after gap creation. The organic matter within the medium gaps decayed more rapidly than those in the small gaps. Among the microenvironmental variables and soil properties, soil temperature was most strongly positively related to organic matter decomposition rates. Medium gaps had high soil temperature and photosynthetically active radiation (PAR) transmittance, and low soil moisture. Within medium gaps, we found a great amount of phenolic compounds and a low content of organic matter and humic acids. These results indicate that in the medium gaps mineralization of organic matter was more important than humification. In contrast, in small gaps, the great amount of organic matter, the high content of humic acid and the values of humification index suggested that in these gaps the humification process of organic matter prevailed. Within small gaps, we observed more silver fir regeneration than medium gaps. Difference in organic matter content, particularly in the amount of phenolic compounds, may account for differences observed in natural regeneration of silver fir between small and medium gaps.  相似文献   
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Changes in the content of low molecular weight phenolic compounds (hydroxybenzoic and hydroxycinnamic acids, aldehydes, and their esterified derivatives, tyrosol and 5-(hydroxymethyl)-2-furaldehyde) during the aging of three different classes of Sherry wine, Fino, Oloroso, and Amontillado, have been studied. The samples studied were taken from each of the scales of the particular aging system applied to the three classes of wine. Clear differences were observed in the behavior of the low molecular weight phenolic in the three classes of wine. The wines subjected to oxidative aging presented a higher phenolic content overall, with the exception of the esterified derivatives of phenolic compounds that are mainly found in the samples that have not undergone any process of oxidation. MANOVA results confirmed that there are significant differences between all of the samples of the three types of wines. Using LDA, a classification of 100% of the samples has been made.  相似文献   
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