Silver nanoparticles are one of the most important materials in the nanotechnology industry. Additionally, the protein corona is emerging as a key entity at the nanobiointerface; thus, a ...comprehensive understanding of the interactions between proteins and silver nanoparticles is imperative. Therefore, literature reporting studies involving both single molecule protein coronas (i.e., bovine and human serum albumin, tubulin, ubiquitin and hyaluronic-binding protein) and complex protein coronas (i.e., fetal bovine serum and yeast extract proteins) were selected to demonstrate the effects of protein coronas on silver nanoparticle cytotoxicity and antimicrobial activity. There is evidence that distinct and differential protein components may yield a "protein corona signature" that is related to the size and/or surface curvature of the silver nanoparticles. Therefore, the formation of silver nanoparticle protein coronas together with the biological response to these coronas (i.e., oxidative stress, inflammation and cytotoxicity) as well as other cellular biophysicochemical mechanisms (i.e., endocytosis, biotransformation and biodistribution) will be important for nanomedicine and nanotoxicology. Researchers may benefit from the information contained herein to improve biotechnological applications of silver nanoparticles and to address related safety concerns. In summary, the main aim of this mini-review is to highlight the relationship between the formation of silver nanoparticle protein coronas and toxicity.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Non-structural carbohydrates (NSC) are major substrates for plant metabolism and have been implicated in mediating drought-induced tree mortality. Despite their significance, NSC dynamics in tropical ...forests remain little studied. We present leaf and branch NSC data for 82 Amazon canopy tree species in six sites spanning a broad precipitation gradient. During the wet season, total NSC (NSC
) concentrations in both organs were remarkably similar across communities. However, NSC
and its soluble sugar (SS) and starch components varied much more across sites during the dry season. Notably, the proportion of leaf NSC
in the form of SS (SS:NSC
) increased greatly in the dry season in almost all species in the driest sites, implying an important role of SS in mediating water stress in these sites. This adjustment of leaf NSC balance was not observed in tree species less-adapted to water deficit, even under exceptionally dry conditions. Thus, leaf carbon metabolism may help to explain floristic sorting across water availability gradients in Amazonia and enable better prediction of forest responses to future climate change.
The structure of the isolated milled “wood” lignin from coconut coir has been characterized using different analytical methods, including Py-GC/MS, 2D NMR, DFRC, and thioacidolysis. The analyses ...demonstrated that it is a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin, with a predominance of G units (S/G ratio 0.23) and considerable amounts of associated p-hydroxybenzoates. Two-dimensional NMR indicated that the main substructures present in this lignin include β–O–4′ alkyl aryl ethers followed by phenylcoumarans and resinols. Two-dimensional NMR spectra also indicated that coir lignin is partially acylated at the γ-carbon of the side chain with p-hydroxybenzoates and acetates. DFRC analysis showed that acetates preferentially acylate the γ–OH in S rather than in G units. Despite coir lignin’s being highly enriched in G-units, thioacidolysis indicated that β–β′ resinol structures are mostly derived from sinapyl alcohol. Finally, we find evidence that the flavone tricin is incorporated into the coconut coir lignin, as has been recently noted for various grasses.
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IJS, KILJ, NUK, PNG, UL, UM, UPUK
In eukaryotes, ARGONAUTE proteins (AGOs) associate with microRNAs (miRNAs), short interfering RNAs (siRNAs), and other classes of small RNAs to regulate target RNA or target loci. Viral infection in ...plants induces a potent and highly specific antiviral RNA silencing response characterized by the formation of virus-derived siRNAs. Arabidopsis thaliana has ten AGO genes of which AGO1, AGO2, and AGO7 have been shown to play roles in antiviral defense. A genetic analysis was used to identify and characterize the roles of AGO proteins in antiviral defense against Turnip mosaic virus (TuMV) in Arabidopsis. AGO1, AGO2 and AGO10 promoted anti-TuMV defense in a modular way in various organs, with AGO2 providing a prominent antiviral role in leaves. AGO5, AGO7 and AGO10 had minor effects in leaves. AGO1 and AGO10 had overlapping antiviral functions in inflorescence tissues after systemic movement of the virus, although the roles of AGO1 and AGO10 accounted for only a minor amount of the overall antiviral activity. By combining AGO protein immunoprecipitation with high-throughput sequencing of associated small RNAs, AGO2, AGO10, and to a lesser extent AGO1 were shown to associate with siRNAs derived from silencing suppressor (HC-Pro)-deficient TuMV-AS9, but not with siRNAs derived from wild-type TuMV. Co-immunoprecipitation and small RNA sequencing revealed that viral siRNAs broadly associated with wild-type HC-Pro during TuMV infection. These results support the hypothesis that suppression of antiviral silencing during TuMV infection, at least in part, occurs through sequestration of virus-derived siRNAs away from antiviral AGO proteins by HC-Pro. These findings indicate that distinct AGO proteins function as antiviral modules, and provide a molecular explanation for the silencing suppressor activity of HC-Pro.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The rising costs of fishmeal worldwide promote great research effort aimed to find alternative and renewable ingredients for aquafeeds. In the last years considerable attention has been paid to the ...use of algae as a potential ingredient for fish feeds. The objective of this work was to evaluate the effects of the microalgae Scenedesmus almeriensis incorporated to diets intended to feed sea bream (Sparus aurata) juveniles in a 45-day trial. Growth, body composition, and intestinal functionality of fish were studied. Microalgae meal was tested in triplicate at different inclusion levels (0%, 12%, 20%, 25% and 39%). At the end of the trial, individual body weight was recorded for evaluation of growth and nutrient utilization, and biological samples were obtained for proximate analysis, determination of digestive enzyme activities, intestinal histology, and microvilli morphological evaluation. Results indicated that S. almeriensis did not cause negative effects on fish growth or nutrient utilization efficiency. Growth rate and protein utilization in fish fed on a diet with 20% Scenedesmus meal tended to be higher, although not significantly different from those fed on control diet. None of the treatments caused adverse effects on body composition. Fish fed 12% S. almeriensis showed higher trypsin than animals fed on control diet. Leucine-aminopeptidase and alkaline phosphatase activities showed a quadratic response with increasing levels of Scenedesmus biomass. Ultrastructural study revealed that the dietary inclusion of algal biomass, especially at 20% level, significantly increased the absorptive capacity of intestinal mucosa in both the anterior and posterior intestinal regions. This study confirmed the usefulness of S. almeriensis to partially replace fishmeal in practical diets for gilthead sea bream juveniles.
•The use of Scenedesmus meal did not affect fish growth and nutrient utilization.•The dietary inclusion of Scenedesmus biomass did not affect muscle composition.•The level of intestinal enzyme activities was increased in Scenedesmus-fed sea bream.•Scenedesmus almeriensis biomass may be useful to enhance gut functionality in fish.•S. almeriensis can partially replace fishmeal in diets for sea bream juveniles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
► The screening showed that very few fungi were suitable to increase sugar recoveries from wheat straw. ► High glucose yields were obtained with the selected fungi. ► Most of glucose released from ...pretreated wheat straw was successfully fermented to ethanol using
Saccharomyces cerevisiae. ► The results suggest that no inhibitors were generated during the whole process.
The potential of a fungal pretreatment combined with a mild alkali treatment to replace or complement current physico-chemical methods for ethanol production from wheat straw has been investigated. Changes in substrate composition, secretion of ligninolytic enzymes, enzymatic hydrolysis efficiency and ethanol yield after 7, 14 and 21
days of solid-state fermentation were evaluated. Most fungi degraded lignin with variable selectivity degrees, although only eight of them improved sugar recovery compared to untreated samples. Glucose yield after 21
days of pretreatment with
Poria subvermispora and
Irpex lacteus reached 69% and 66% of cellulose available in the wheat straw, respectively, with an ethanol yield of 62% in both cases. Conversions from glucose to ethanol reached around 90%, showing that no inhibitors were generated during this pretreatment. No close correlations were found between ligninolytic enzymes production and sugar yields.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this work we compared the efficiency of a laccase treatment performed on steam-exploded wheat straw pretreated under soft conditions (water impregnation) or harsh conditions (impregnation with ...diluted acid). The effect of several enzymatic treatment parameters (pH, time of incubation, laccase origin and loading) was analysed. The results obtained indicated that severity conditions applied during steam explosion have an influence on the efficiency of detoxification. A reduction of the toxic effect of phenolic compounds by laccase polymerization of free phenols was demonstrated. Laccase treatment of steam-exploded wheat straw reduced sugar recovery after enzymatic hydrolysis, and it should be better performed after hydrolysis with cellulases. The fermentability of hydrolysates was greatly improved by the laccase treatment in all the samples. Our results demonstrate the action of phenolic compounds as fermentation inhibitors, and the advantages of a laccase treatment to increase the ethanol production from steam-exploded wheat straw.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Electron Backscattering Diffraction (EBSD) provides important information to discriminate phase transformation products in steels. This task is conventionally performed by an expert, who carries a ...high degree of subjectivity and requires time and effort. In this paper, we question if Convolutional Neural Networks (CNNs) are able to extract meaningful features from EBSD-based data in order to automatically classify the present phases within a steel microstructure. The selected case of study is ferrite-martensite discrimination and U-Net has been selected as the network architecture to work with. Pixel-wise accuracies around ~95% have been obtained when inputting raw orientation data, while ~98% has been reached with orientation-derived parameters such as Kernel Average Misorientation (KAM) or pattern quality. Compared to other available approaches in the literature for phase discrimination, the models presented here provided higher accuracies in shorter times. These promising results open a possibility to work on more complex steel microstructures.
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•Deep Learning Convolutional Neural Networks were successfully applied to EBSD maps.•Beyond 98% accuracy to discriminate Ferrite from Martensite in a Dual Phase Steel•Misidentifications occurred in Widmanstätten ferrite and autotempered martensite.•Relatively few labeled EBSD maps are required for training.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, SBCE, UL, UM, UPCLJ, UPUK, ZAGLJ
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