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This study explored the expression and the perception of vocal emotions in L2 learners of Italian coming from different countries. We carried out an acoustic analysis of learners’ emotional speech in their L1s and in Italian, to verify to what extent their L1 influenced their productions in L2. To test learners’ ability to decode vocal emotions expressed by natives, we administered a perception test containing emotional stimuli in Italian; to verify the effectiveness of learners’ emotional speech, we administered a perception test to Italian listeners. Results revealed that learners’ productions were influenced by their L1s, consequently Italians experienced difficulties in decoding them. Learners encountered the same difficulties in identifying natives’ emotional speech. Such awareness could be useful for L2 teaching practices.

An ideal therapeutic anti-SARS-CoV-2 antibody would resist viral escape1-3, have activity against diverse sarbecoviruses4-7, and be highly protective through viral neutralization8-11 and effector functions12,13. Understanding how these properties relate to each other and vary across epitopes would aid the development of therapeutic antibodies and guide vaccine design. Here we comprehensively characterize escape, breadth and potency across a panel of SARS-CoV-2 antibodies targeting the receptor-binding domain (RBD). Despite a trade-off between in vitro neutralization potency and breadth of sarbecovirus binding, we identify neutralizing antibodies with exceptional sarbecovirus breadth and a corresponding resistance to SARS-CoV-2 escape. One of these antibodies, S2H97, binds with high affinity across all sarbecovirus clades to a cryptic epitope and prophylactically protects hamsters from viral challenge. Antibodies that target the angiotensin-converting enzyme 2 (ACE2) receptor-binding motif (RBM) typically have poor breadth and are readily escaped by mutations despite high neutralization potency. Nevertheless, we also characterize a potent RBM antibody (S2E128) with breadth across sarbecoviruses related to SARS-CoV-2 and a high barrier to viral escape. These data highlight principles underlying variation in escape, breadth and potency among antibodies that target the RBD, and identify epitopes and features to prioritize for therapeutic development against the current and potential future pandemics.

SARS-CoV-2 can mutate and evade immunity, with consequences for efficacy of emerging vaccines and antibody therapeutics. Here, we demonstrate that the immunodominant SARS-CoV-2 spike (S) receptor binding motif (RBM) is a highly variable region of S and provide epidemiological, clinical, and molecular characterization of a prevalent, sentinel RBM mutation, N439K. We demonstrate N439K S protein has enhanced binding affinity to the hACE2 receptor, and N439K viruses have similar in vitro replication fitness and cause infections with similar clinical outcomes as compared to wild type. We show the N439K mutation confers resistance against several neutralizing monoclonal antibodies, including one authorized for emergency use by the US Food and Drug Administration (FDA), and reduces the activity of some polyclonal sera from persons recovered from infection. Immune evasion mutations that maintain virulence and fitness such as N439K can emerge within SARS-CoV-2 S, highlighting the need for ongoing molecular surveillance to guide development and usage of vaccines and therapeutics.

Analysis of the specificity and kinetics of neutralizing antibodies (nAbs) elicited by SARS-CoV-2 infection is crucial for understanding immune protection and identifying targets for vaccine design. In a cohort of 647 SARS-CoV-2-infected subjects, we found that both the magnitude of Ab responses to SARS-CoV-2 spike (S) and nucleoprotein and nAb titers correlate with clinical scores. The receptor-binding domain (RBD) is immunodominant and the target of 90% of the neutralizing activity present in SARS-CoV-2 immune sera. Whereas overall RBD-specific serum IgG titers waned with a half-life of 49 days, nAb titers and avidity increased over time for some individuals, consistent with affinity maturation. We structurally defined an RBD antigenic map and serologically quantified serum Abs specific for distinct RBD epitopes leading to the identification of two major receptor-binding motif antigenic sites. Our results explain the immunodominance of the receptor-binding motif and will guide the design of COVID-19 vaccines and therapeutics.

Cestrum parqui L'Herit. (Solanaceae family) is a species of forest shrub, self-incompatible and specialized in pollination, widespread in the subtropical area of the planet, and now widely distributed also in the Mediterranean area. The constituents of its leaves have antimicrobial, anticancer, insecticidal, antifeedant, molluscicidal, and herbicidal properties. The spread of this species represents a valuable source of compounds with high biological value. Various research groups are engaged in defining the chemical composition of the different parts of the plant and in defining its properties in view of important and promising commercial applications. To date, there are only a few incomplete reports on the potential applications of C. parqui extracts as selective natural pesticides and on their potential phytotoxic role. Scientific knowledge and the use of extraction techniques for these components are essential for commercial applications. This article summarizes the research and recent studies available on the botany, phytochemistry, functional properties, and commercial applications of C. parqui. [ABSTRACT FROM AUTHOR]

The land use change can negatively impact ecosystems, enriching water and soil with heavy metals (HMs). The fragile riparian areas along the Medjerda River of Northern Algeria are particularly affected by this phenomenon, and biological tools able to combine information about both matrices can be preferred in their monitoring. This research aimed to evaluate the suitability of the spiny toad (Bufo spinosus D.) as a biomonitor for assessing the impact of three different land uses (agricultural (AGR), urban (URB), and industrial (IND) managements) on soil and water for Cu, Fe, Pb, and Zn by using the non-lethal skin biopsy. The IND land use, followed by URB, mostly impacted soils for Cu and Pb, whereas management was not able to influence water differently despite worrying Pb levels. The cluster analysis allows to show that toad responds like soil in terms of land use and like water for HMs, as it is possibly related to the metal–chemical affinity. Although the single skin analyses do not display any difference among the managements, the bioaccumulation factor (BF > 1) shows that B. spinosus absorbs more HMs from water; skin accumulates Fe and Zn regardless of the land use, probably for both natural and anthropogenic assimilation and Pb and Cu for URB and IND, as it is related to their ionic forms and human impact. [ABSTRACT FROM AUTHOR]

Secondary metabolites extracted from plants have historically been critical for drug discovery, but their isolation involves expensive and complicated procedures in terms of time and labor resources. Thus, the biogenetic pathway offers the possibility of identifying specific compounds that have not yet been isolated and predicting their isolation from specific natural sources. In plants, biphenanthrenes represent a relatively small group of aromatic secondary metabolites that are considered as important taxonomic markers with promising biological activities. To date, 38 mixed phenanthrenoid dimers have been identified, the biosynthesis of which involves the radical coupling of the two subunits, namely, a phenanthrene and a dihydrophenanthrene. For each of the compounds, it is possible to identify the single phenanthrenic and dihydrophenanthrenic units constituting the considered dimer. Based on the biogenetic pathway, it is possible to identify 19 phenanthrenes and 17 dihydrophenanthrenes, and to distinguish those already known from those not yet isolated. By comparing the results of the possible biosynthetic pathway for each compound with the data in the literature, it is possible to identify three known phenanthrenes and seven known dihydrophenanthrenes, as well as eleven new phenanthrenes and five new dihydrophenanthrenes, and to identify from which plant it is possible to isolate them. This could direct the work of researchers seeking to identify known or new molecules useful for their possible biological properties, and ultimately, to confirm the veracity of the proposed and generally accepted biosynthetic pathway. [ABSTRACT FROM AUTHOR]

The goals of the current research were to assess the immediate impact of invasive wild boar (Sus scrofa L.) in olive orchards of southern Italy. Over a one-year study, in grubbed and ungrubbed areas, we measured the seasonal changes on the fast soil biological and chemical responses at depths of 0–15 cm and 15–40 cm, and several leaf and fruit characteristics. The impact factor, IFG, was used to quantify the effects of wild boar on individual soil parameters. Grubbing induced an increase in the soil moisture at both depths. Soil pH, organic matter, and C/N ratio were higher in grubbed soils at 0–15 cm and lower at 15–40 cm compared to ungrubbed soils. These trends were reflected in the higher microbial community biomass and the inhibition of fungal fraction in grubbed topsoil, while an opposite tendency at 15–40 cm was found. Microbial biomass had the highest IFG in topsoil (94%) and metabolic quotient (85%) at a 15–40 cm depth. Microbial stress condition and C loss were found in grubbed soil at both depths. Furthermore, these soils were also shown to be of lower quality than ungrubbed soils, especially at 0–15 cm (SQI = 0.40 vs. 0.50, respectively). A stronger negative impact of wild boar grubbing was observed in the Autumn/Winter and for fruit polyphenol content. [ABSTRACT FROM AUTHOR]

Question: Cushion‐forming vascular plants are adapted to alpine environments and act as ecosystem engineers by moderating microclimate and creating a fertility island under their canopy. Most of the available studies on cushion ecology have been devoted to plant facilitation, but none used a holistic approach that considers the response of co‐existing plant species with other key ecosystem players. Here, we quantified the biogenic effect and facilitation capacity of Astragalus siculus, a spiny nitrogen‐fixing cushion plant, and test the hypothesis that the facilitation effect would increase with elevation as stress gradient. Location: Mount Etna, the highest active volcano in the Mediterranean Basin. Methods: We combined chemical characterization of the soil with a description of the soil microbiota by high‐throughput sequencing of bacterial and eukaryotic rRNA gene markers carried out at three elevations, that is 1650, 1900 and 2210 m a.s.l. In addition, we analysed the microclimate outside and inside the Astragalus canopy to assess the linkages between above‐ and below‐ground ecosystem compartments and quantified the occurrence of co‐existing vascular plants. Results: Astragalus cushions have strong biogenic effects on above‐ and below‐ground conditions by dramatically increasing soil organic carbon and total nitrogen stocks at 1900 and 2210 m elevation. Moreover, a buffering of soil temperature and moisture regimes was recorded, with lower temperatures in summer but higher in winter inside the cushions. Cushions harbour a specific bacterial and fungal microbiota compared to external bare soil. Stem density and cushion height increase significantly with altitude, as does the nurse effect of the cushion on the growth and survival of co‐existing vascular plants. Conclusions: As a result of cushion biogenic environmental changes, the effect of Astragalus on some of the co‐existing species shifted from negative or null at 1650 m to facilitative along the elevation gradient. Furthermore, our data show a relationship between Astragalus morphological traits and soil biogenic changes related to soil chemistry and microbiota that affect plant interaction and coexistence. [ABSTRACT FROM AUTHOR]

Forest soils harbour a vast array of organisms that govern the processing of organic matter. Through their trophic interactions, they give rise to carbon flows that sustain soil ecosystem functioning. Understanding how soil food webs shape carbon flows may enhance our knowledge about the role of biodiversity on soil processes.In this work, we assembled trophic networks representing soil food webs of two beech forests during spring and autumn, and compiled mass‐balanced models quantifying carbon flows between their components. These models were investigated using network analysis to identify the role of the components on carbon flow, cycling and functional trophic relationships. Moreover, we explored how the structure of carbon exchanges promote efficiency and stability.Results indicate the importance of indirect interactions. Most trophic groups exhibit a diffuse dependency on all the compartments for their carbon requirement although certain groups such as Collembola play the role of hubs in distributing carbon. Indirect interactions often reverse the impacts of direct trophic relationships being antagonistic to the direction of change predicted based on predator–prey interactions. The high incidence of generalist feeding habits increases the redundancy of energy channels thereby making such food webs more resilient against perturbations but at the expense of carbon transfer efficiency.Although differences can be observed across sites and periods, food web structure rather than environmental variability seems to be the main factor responsible for patterns of carbon flows in the two beech forests. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

A main reason of the increasing interest in cereal landraces is their potential to offer more diversified and functional staple food. For instance, landraces are an underexploited resource of pigmented varieties, appreciated for the high accumulation of phytochemicals with known health benefits. This study characterized the chemical, functional, and technological features of the bran, semolina, and grains of two durum wheat (Triticum turgidum L. subsp. durum, Desf.) landraces, named 'Purple' and 'Red' for their grain color, collected in Ethiopia and grown and sold in southern Italy as a niche product. Specifically, we analyzed the protein content, dry gluten, ash, total polyphenols, anthocyanins, proanthocyanidins, and specific phenolic acids. We also evaluated the antioxidant activity using DPPH- and ABTS-based methods. The two landraces had positive nutritional features, such as a high protein content, a rich and composite range of secondary metabolites (which include specific phenolic acids and anthocyanins), and antioxidant activities in all the fractions analyzed. The germplasm under investigation therefore has a well-justified potential to yield functional products and to diversify durum wheat-based foods. [ABSTRACT FROM AUTHOR]

As they quickly respond to environmental conditions, soil enzymes, involved in nutrient cycles, are considered good indicators of soil quality. The Mediterranean area is a peculiar environment for climatic conditions and for fire frequency. Therefore, the research aimed to evaluate the role of seasonality and fire on enzymatic activities (i.e., hydrolase, dehydrogenase, and β-glucosidase) in soils covered by herbs, black locust, pine, and holm oak. In addition, the main soil abiotic properties that drive the enzymatic activities were also investigated. In order to achieve the aims, surface soils were collected in unburnt and burnt areas and characterized for water and organic matter contents, pH, concentrations of C and N, and available fractions of Al, Ca, Cu, Fe, Mg, Mn, Na, and Pb. The results highlighted that the soil enzymatic activities were mainly affected by seasonality more than by fire; in unburnt soils, their main drivers were nutrient availabilities, whereas, in burnt soils they were pH, water and organic matter contents, C and N concentrations, and both nutrient and metal availabilities. Finally, holm oak, as compared with herbs, pine, and black locust, conferred higher stability to soils that were affected by seasonality and fire. [ABSTRACT FROM AUTHOR]

The aim of this work is to compare new and traditional extraction methods to obtain silymarin from Silybum marianum, a biennial herbaceous plant of the Asteraceae family, present throughout the Mediterranean basin and used to treat several diseases. Silymarin primarily contains flavonolignans and flavonoids and is used in some pharmaceutical preparations to improve of liver function and as a protective against some hepatotoxins. In six extracts obtained by new and traditional extraction methods, the total contents of silymarin and its main flavonolignans, total phenols and condensed tannins were evaluated in addition to their respective antioxidant capacities. By the Naviglio extractor, that is a rapid solid-liquid dynamic extraction method, it is possible to obtain a fraction quantitatively more abundant than other methods, and with a lower content of tannins and phenolic compounds but with a higher content of flavonolignans, rare and expensive, and therefore easier to separate and purify. [ABSTRACT FROM AUTHOR]

The intensive wildfires recurring in the Mediterranean area modify soil physico-chemical properties, in turn inducing changes in soil microbial abundance and activity. Soils were sampled from burnt and adjacent unburnt sites within Vesuvius National Park 1 year after a large wildfire occurred in summer 2017. The aims of the present study were to evaluate the effects of fires on soil characteristics and to investigate whether different plant types contribute to mitigating or enhancing these effects. The results showed lower organic matter and water content and a higher C/N ratio in burnt than in unburnt soils. In particular, this trend was the same for all the plant types investigated, with the exception of soils covered by black locust tree and holm oak, which showed a higher C/N ratio in unburnt than in burnt soils. In soils covered by holm oaks, a shift in the bacterial and fungal fractions occurred between burnt and unburnt soils, whereas the amount of ammonia oxidisers was notably higher in burnt than in unburnt soils covered by black locusts; the highest N concentration was also measured in burnt soils covered by black locusts. The burnt soils showed a lower metabolic quotient and a higher rate of organic carbon mineralisation compared with unburnt soils, and this trend was particularly evident in soils under herbaceous plants. The findings suggest that soils covered by herbaceous species are more sensitive to fire effects and less able to restore their functionality compared with soils covered by trees. Wildfires seem to amplify the differences for quantity and quality of soil organic matter and microbial amount and activity in soils under herbaceous and tree covers. This study investigated soil properties and microbial communities after fires that occurred in the summer of 2017 in Vesuvius National Park. Soils covered by herbaceous species, compared with those covered by trees, seem to be more sensitive to the overall variations owing to fire, and less able to restore their functionality – probably a result of the lowest microbial abundance and higher carbon losses. [ABSTRACT FROM AUTHOR]

Litter decomposition mobilizes nutrients that sustain ecosystem productivity, but decomposition by‐products may also hamper root proliferation by phytotoxicity. The aim of this study was to assess the litter substrate preferences of tropical tree seedlings in relation to litter chemical traits. We characterized 44 litter types (11 species at four decomposition ages; 0, 30, 90 and 180 days) for nutrients (N, P, K, Mg, Mn, Na, Fe and Zn) and proximate chemical parameters (cellulose, extractive, lignin and C) and tested the effect of such litter materials on seedling root growth of Albizia procera, Dalbergia sissoo and Terminalia arjuna. Albizia procera root growth was inhibited by all litter types and ages, including conspecific materials, while different heterospecific litters had inhibitory or stimulatory effect on D. sissoo and T. arjuna root growth, compared to the control. Interestingly, inhibitory and stimulatory effects of heterospecific litters significantly changed with litter age, although with no clear‐cut pattern among target species and litter species and age, while conspecific litters consistently inhibited root growth when aged, but not when fresh. Litter nutrient, extractive, C, cellulose and lignin showed no consistent association with root growth of tested plants. Albizia procera root growth was positively associated with Na content and N:P ratio. Dalbergia sissoo root growth was positively associated to C:N and lignin:N ratios, and negatively to K, Na and Zn content. Finally, T. arjuna root was positively associated to cellulose and N:P ratio, but negatively to extractive. We conclude that studied nutrient, cellulose and lignin do not consistently explain the species‐specific response of root of tree seedlings to decomposing litter. [ABSTRACT FROM AUTHOR]

Background and aim: Litter decomposition is of great concern as it plays a key role in regulating global carbon cycle and nutrient budgets, especially in tropical forests where it is very fast. Therefore, we studied the decomposition and subsequent changes in element concentrations and amounts of 11 tropical leaf litter.Methods: Fresh litters were characterized in terms of elemental, proximate features, as well as organic carbon compositions by 13C-NMR spectroscopy. Controlled litterbag decomposition was carried out for 180 days in the laboratory, bags were retrieved at three dates and analyzed for mass loss and concentration of nitrogen (N), potassium (K), sodium (Na), carbon (C), magnesium (Mg), manganese (Mn), iron (Fe), phosphorus (P), zinc (Zn), and percentage of ash, extractives, cellulose and lignin.Results: Terminalia arjuna showed highest mass loss, while the lowest was observed in Shorea robusta showing significant positive correlation with litter initial K, Mg, Fe and di-O-alkyl C, O-alkyl C, while significant negative correlation with Mn, lignin and Methoxyl C, Alkyl C. Trajectories shows that Fe, Mg, K, Mn, Zn and Na concentrations increased in most of the litter types, except Terminalia arjuna and Toona ciliata, where Fe, Mg, K concentrations decreased during decomposition. Surprisingly, in most of the species with the exception of Terminalia arjuna, N concentrations decreased at a faster rate than C concentrations, resulting in an increase in C/N ratios. Expectedly, lignin progressively increased, while cellulose decreased.Conclusions: Observed differences in decomposition rate and dynamics of chemical changes among litters were strongly affected by the litter type, decomposition time and their interactions. [ABSTRACT FROM AUTHOR]