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During last years, skin pitting symptoms on kiwifruit, caused by Cadophora luteo-olivacea, were detected in packaging houses of different geographic areas. In this study, the kiwifruits ripeness stage was considered a possible condition influencing fungal virulence. FT-IR analysis confirmed that unripe kiwifruits are more susceptible to fungal attack. By observations at the Scanning Electron Microscope (SEM), we were able to follow month by month C. luteo-olivacea infection strategy. Once inside kiwifruit, the pathogen can colonize kiwifruit pulp just under the skin starting from the first month but modifying its structural composition only in the third and fourth months. [ABSTRACT FROM AUTHOR]

The most common leguminous plants' diseases are caused by soil-borne pathogens leading to important economic losses worldwide. Strains L1 and L8, belonging to Aureobasidium pullulans species, were tested in vitro and in vivo as biocontrol agents (BCAs) against Rhizoctonia solani (Rs1) (AG-4) and as plant growth promoters (PGPs). The non-volatile metabolites produced by L1 and L8 strains inhibited the pathogen mycelial growth by 87.9% on average, with no significant differences between the two strains. The lower pathogen diametric growth inhibition was displayed by both yeasts' volatile metabolites (VOCs) that significantly reduced the colony growth of R. solani, and similarly to the control, with an average of 10.5%. By in vivo assay, L1 and L8 strains showed the ability to control the pathogen virulence probably through the biofilm formation around the bean and soybean plant roots, as confirmed by scanning electron microscope (SEM) analysis. The spectroscopic analysis highlighted the composition of non-volatile compounds: complex carbohydrates (pullulan), degrading enzymes, siderophores and antifungals (aureobasidins). Moreover, the ability of L1 and L8 strains to stimulate the bean and soybean plant roots, stems, and leaves growth was investigated, showing that these yeasts could have an application not only as BCAs but also as plant growth biostimulator. [ABSTRACT FROM AUTHOR]

Despite their economic and ecological interests, Poaceae are affected by the low availability of iron in calcareous soils. Several studies focused on the capacity of this family to secrete phytosiderophores and organic acids as a mechanism of tolerance to iron deficiency. This work aimed at studying the physiological responses of two Poaceae species; Hordeum vulgare (cultivated barley) and Polypogon monspenliensis (spontaneous species) to iron deficiency, and evaluate especially the release of phytosiderophores and organic acids. For this purpose, seedlings of these two species were cultivated in complete nutrient solution with or without iron. The biomass production, iron status, phytosiderophores and organic acids release by roots were studied. The results demonstrated that Polypogon monspenliensis was relatively more tolerant to iron deficiency than Hordeum vulgare. Polypogon monspenliensis had the ability to secrete a higher amount of phytosiderophores and organic acids, especially citric, acetic, oxalic and malic acids, compared to Hordeum vulgare. We propose this spontaneous species as a forage plant in calcareous soils and in intercropping systems with fruit trees to prevent iron chlorosis. [ABSTRACT FROM AUTHOR]

Due to climate change, Neofusicoccum parvum is currently emerging as a new pathogen of Rosaceae plant species. This increases the need of gaining knowledge on the pathogenicity of this fungus, particularly on apple cultivars of considerable economic importance. In this study, the virulence and temperature dependence of N. parvum isolates was assayed on 'Gala' and 'Fuji' apple fruit and wood. At 25 °C and 30 °C, 'Gala' fruits showed a higher susceptibility to all fungal strains than 'Fuji', whereas low infection severity was shown at 15 °C and 20 °C on both cultivars. Infrared spectroscopy revealed that 'Fuji' fruit tissues displayed a higher content of phenolic compounds and pectin esterification degree, as factors possibly correlated with fruit susceptibility. When strain virulence was assayed on wood, no significant difference in susceptibility was detected, as also shown by SEM analysis. The virulence of N. parvum was also tested by assaying the activity of lytic enzymes such as cellulase, polygalacturonase, polymethylgalacturonase, and xylanase. [ABSTRACT FROM AUTHOR]

Purpose: Pyrogenic organic matter (PyOM) in the soil of a maritime pine forest in Central Italy, formed during a fire of high severity, was characterised by Fourier transform infrared (FT-IR) and C nuclear magnetic resonance (NMR). Furthermore, soil samples from burnt and unburnt sampling sites and natural charcoal collected from the ground were characterised after progressive heating under air and nitrogen atmosphere. The aim was to better understand the role fire plays on PyOM formation and oxidation. Materials and methods: The top 10 cm of mineral soil and the above-lying charcoal particles were collected soon after the fire. Sampling was also performed on an adjacent unburnt portion of the forest. The bulk soil organic matter (SOM), its extractable fraction and charcoal particles were investigated by FT-IR and C NMR spectroscopies. They also underwent thermogravimetric analysis under air or N, stopping the thermal reactions at the end of the first exothermic reaction in the range 350-500 °C. Results and discussion: The NMR investigation clearly revealed a significant enrichment in aromatic and alkyl C in the burnt soil compared to the unburnt one. Several clues led to hypothesise that SOM was not exposed to extreme heating during the fire, notwithstanding the high fire severity estimated by a vegetation-based visual scale. In the thermal treatment mimicking fire, charcoal lost much of its mass and carbon content. However, at 500 °C, it still maintained a significant recalcitrant fraction. Nitrogen concentration in the bulk soil increased after heating, particularly under air condition. This phenomenon could be due to the formation of heterocyclic nitrogen compounds in the charred material. Conclusions: In the study area, PyOM is rich in aliphatic compounds presumably because of the understory sclerophyllous vegetation typically found in Mediterranean environments. A large fraction of the charcoal released to the soil during the fire is sensitive to oxidation by subsequent fires. On the other hand, charcoal preserves a significant fraction of C, the most recalcitrant one, with expected long residence time in soil. PyOM formed under high oxygen availability is richer in N than that formed in inert atmosphere, which might make PyOM more susceptible to biochemical degradation. [ABSTRACT FROM AUTHOR]

In this paper, the effect of increasing amounts of lysozyme (Lyso) and bovine serum albumin (BSA) on the behaviour of lecithin (DMPC) and cephalin (DMPE) liposomes was investigated by means of Raman and DSC techniques. The results showed that both proteins affected, but in a different way, both lecithin and cephalin liposomes. In the samples with lower Lyso concentrations (up to 2 % w/w), a small decrease on the main transition temperature ( T) was observed, whereas T increased by further addition of Lyso (up to 15.0 % w/w). At the same time, an increase of about 20 % in the Δ H of the transition was observed. Pre-transition was also affected in a greater extent by protein presence. When BSA interacted with liposomes, a smaller increase in the T values was observed with a contemporary increase of about 8 % in the associated Δ H. The data suggested that the BSA-liposomes interaction involves only the external surface of the bilayer, excluding thus any penetration into the liposomal hydrophobic core. On the contrary, a partial penetration into the bilayer is suggested when Lyso is added to liposomes. Both considered proteins strengthened the overall bilayer structure of DMPC liposomes, suggesting a decrease in the membrane permeability. Moreover, Lyso secondary structure changed by interaction with liposomes, as demonstrated by the Raman spectra behaviour, in particular in the case of DMPE. [ABSTRACT FROM AUTHOR]

Lactoferrin (LF), a non-heme iron-binding protein of blood plasma and milk with antioxidant, cariostatic, anticarcinogenic, and anti-inflammatory properties, has been studied by differential scanning calorimetry (DSC) and Raman spectroscopy over a wide pH range (4.0-9.0). Using these two techniques, the modifications in the quantity of iron bounded in the cow's milk LF and in the secondary structures, as a function of pH and heating, have been evaluated. DSC curves showed higher value of denaturation temperatures and enthalpy changes when LF was saturated with iron (holo-form) than when it was in its unsaturated form (apo-form). The denaturation curves of the protein solutions at pH ≥ 5.5 confirming that LF is a mix of apo- and holo-forms; on the contrary at pH 4.0, the holo-form is practically absent. Spectroscopic investigation showed that, as a function of pH, the content of α-helix increases up to pH 7.4, followed by a small decrease by further pH increase. The β-sheet percentage exhibits the opposite behavior, while the random-coil and turn structures do not change noticeably. In contrast, after heat-induced denaturation, strong variations were observed in the secondary structure, with an evident increase of β-sheet and decrease of the α-helix percentage. Finally, both thermal and spectroscopic analysis pointed out that the structure of cow's milk LF is strictly sensible to pH variation and it has the highest thermal stability at physiological pH. [ABSTRACT FROM AUTHOR]

The effects of a high energy sterilization treatment on poly-ε-caprolactone/carbonated hydroxyapatite composites have been investigated. Poly-ε-caprolactone is a biodegradable polymer used as long-term bioresorbable scaffold for bone tissue engineering and carbonated hydroxyapatite is a bioactive material able to promote bone growth. The composites were gamma-irradiated in air or under nitrogen atmosphere with doses ranging from 10 to 50 kGy (i.e. to a value higher than that recommended for sterilization). The effects of the irradiation treatment were evaluated by vibrational spectroscopy (IR and Raman spectroscopies) coupled to thermal analysis (Differential Scanning Calorimetry and Thermogravimetry) and Electron Paramagnetic Resonance spectroscopy. Irradiation with the doses required for sterilization induced acceptable structural changes and damaging effects: only a very slight fragmentation of the polymeric chains and some defects in the inorganic component were observed. Moreover, the radiation sensitivity of the composites proved almost the same under the two different atmospheres. [ABSTRACT FROM AUTHOR]

A serious problem in the production of gas turbine blades is the detection of residual ceramic cores inside the cooling passages; in fact, the presence of even small ceramic pieces affects turbine performance and may cause difficulties in successive manufacturing. Therefore, it is important to have a non-destructive technique that must be capable of detecting tiny ceramic fragments in a fast and easy way. In this perspective, the suitability of infrared thermography was investigated within cooperation between the University of Naples and the Europea Microfusioni Aerospaziali S.p.A. (EMA). Several blades of three different types were inspected revealing that in many cases infrared thermography can discover small ceramic fragments which were missed by X-ray inspection. In addition, infrared thermography allows gaining of information about other types of anomalies (e.g., surface defects) during the same testing step (by eventually changing the test parameters) and then saving time and money. The obtained results look promising in view of introducing infrared thermography among industrial instrumentation as an alternative to, or integrated with, the most currently utilized non-destructive techniques. [ABSTRACT FROM AUTHOR]

Irreversible photoreceptor cell death is a major cause of blindness in many retinal dystrophies. A better understanding of the molecular mechanisms underlying the progressive loss of photoreceptor cells remains therefore crucial. Abnormal expression of microRNAs (miRNAs) has been linked with the aetiology of a number of retinal dystrophies. However, their role during the degenerative process remains poorly understood. Loss of cone photoreceptors in the human macula has the greatest impact on sight as these cells provide high acuity vision. Using a Chrnb4-cre; Dicerflox/flox conditional knockout mouse (Dicer CKO) to delete Dicer1 from cone cells, we show that cone photoreceptor cells degenerate and die in the Dicer-deleted retina. Embryonic eye morphogenesis appeared normal in Dicer CKO mice. Cone photoreceptor abnormalities were apparent by 3 weeks of age, displaying either very short or absent outer segments. By 4 months 50% of cones were lost and cone function was impaired as assessed by electroretinography (ERG). RNAseq analysis of the Dicer CKO retina revealed altered expression of genes involved in the visual perception pathway. These data show that loss of Dicer1 leads to early-onset cone cell degeneration and suggest that Dicer1 is essential for cone photoreceptor survival and homeostasis. [ABSTRACT FROM AUTHOR]

The research aims to investigate the nature of the materials used in the decoration of the cover of a sunk-panel Commissione Dogale, a Venetian manuscript of 1582. The analysed volume Ms. It. VII, 1869 (= 8134) belongs to the collections of the Biblioteca Nazionale Marciana, Venice. The Commissioni were intended as official documents written on parchment and issued by the Doge of Venice. Their bindings were very rich in decoration, especially those produced in the late 16th century. This manuscript is a sumptuous example of the Venetian Renaissance artisanship influenced by Middle Eastern style: its cover was made of gilded leather, painted with arabesque branches and buds and lastly lacquered. The scientific examination of the lavishly illuminated cover was performed before the book-binding conservation treatment, as the characterisation of the decoration materials allowed to plan an appropriate conservation project. The research first step has been the non-invasive observation of the cover surface by digital microscope through UV-VIS radiations. Then, the study of the composition of these materials has been carried out with ATR-FTIR spectroscopy, Raman spectroscopy, XRF spectroscopy and spot-test analyses on samples. Pigments like minium, green earth, a lead-based yellow and smalt have been detected in the painted layer, while a precise identification of the resins and varnishes layered on top of the decoration was not possible because of the heterogeneity of samples. Furthermore, the materials used for this cover can be usefully compared with those detected by other recent analyses carried out on a variety of 16th century Venetian book illuminations. [ABSTRACT FROM AUTHOR]