Electron transfer induced fragmentation of acetic acid

We present negative ion formation driven by electron transfer in atom (K) molecule (acetic acid) collisions. Acetic acid has been found in the interstellar medium, is also considered a biological related compound and as such studying low energy electron interactions will bring new insights as far as induced chemistry is concerned.publishersversionpublishe

CNO- formation through selective bond cleavage

H- and CNO- site and bond selectivity formation is shown in the context of atom-molecule collisions.publishersversionpublishe

Fish communities in the lower Tagus inland wetlands: from anthropogenic pressures to conservation management

Inland wetlands are important biodiversity hotspots and amongst the most impacted ecosystems worldwide. Conservation management and restauration actions in wetlands are thus urgently needed to reverse trends in species loss and habitat degradation, particularly in regions harbouring already endangered endemic species. Inland wetlands may play an important role in supporting endemic endangered fishes in the Lower Tagus basin, where anthropogenic pressures have been increasing, but there is a lack of studies on fish communities, and few areas are identified as inland wetlands. Here, we aim to identify small inland wetlands in the Lower Tagus River and their potential role in supporting fish species, constituting the first study to identify and evaluate the most important fish communities. Inland wetlands were identified through the usage of remote sensing techniques and the calculation of a Normalized Difference Water Index (NDWI) with Sentinel-2 imagery for the Lower Tagus region. From a total of 486 locations identified, 31 were recognized as wetlands as having potential to host fish communities, with 11 being selected for sampling after in loco assessment. Fish sampling was conducted between 6 May and 11 June 2021. Furthermore, for each wetland, we evaluated anthropogenic stressors and land use changes between 2007 and 2018, using national land use data (i.e., Carta de Uso e Ocupação do Solo). A total of 7727 fishes from eight non-native and five native species were captured. Overall, fish communities were dominated by non-native species (97% catches), but both European eel (Anguilla anguilla) and Lisbon arched-mouth nase (Iberochondrostoma olisiponense), which are globally classified as critically endangered (CR), were found in at least two wetlands. Our results suggest that, over the last 10 years, intensive agriculture decreased (on average ≈ 3%) in the areas surrounding these wetlands, being replaced by extensive agriculture or natural uses. Despite non-native fish prevalence, some wetlands may act as refuge habitats for CR fish species. These results are important for guiding the restoration of inland wetlands and promoting conservation management actions to help reverse fish diversity loss.info:eu-repo/semantics/publishedVersio

IL-9 expression by invariant NKT cells is not imprinted during thymic development

Copyright © 2015 by The American Association of Immunologists, Inc. All rights reservedInvariant NKT (iNKT) cell thymic development can lead to distinct committed effector lineages, namely NKT1, NKT2, and NKT17. However, following identification of IL-9-producing iNKT cells involved in mucosal inflammation, their development remains unaddressed. In this study, we report that although thymic iNKT cells from naive mice do not express IL-9, iNKT cell activation in the presence of TGF-β and IL-4 induces IL-9 secretion in murine and human iNKT cells. Acquisition of IL-9 production was observed in different iNKT subsets defined by CD4, NK1.1, and neuropilin-1, indicating that distinct functional subpopulations are receptive to IL-9 polarization. Transcription factor expression kinetics suggest that regulatory mechanisms of IL-9 expression are shared by iNKT and CD4 T cells, with Irf4 and Batf deficiency deeply affecting IL-9 production. Importantly, adoptive transfer of an enriched IL-9(+) iNKT cell population leads to exacerbated allergic inflammation in the airways upon intranasal immunization with house dust mite, confirming the ability of IL-9-producing iNKT cells to mediate proinflammatory effects in vivo, as previously reported. Taken together, our data show that peripheral iNKT cells retain the capacity of shaping their function in response to environmental cues, namely TGF-β and IL-4, adopting an IL-9-producing NKT cell phenotype able to mediate proinflammatory effects in vivo, namely granulocyte and mast cell recruitment to the lungs.This work was supported by Fundação Para a Ciência e Tecnologia, Portugal Grants PTDC/SAU-TOX/114424/2009 and HMSP-ICT/0034/2013 and the Novo Nordisk/European Foundation for the Study of Diabetes (to L.G.), as well as by grants from the Fundação Para a Ciência e Tecnologia, Portugal, the European Molecular Biology Organization, the European Research Council, and the U.S. National Blood Foundation (to H.V.-F.). A.A.-D., C.F.A., D.F.-P., and M.M. were supported by fellowships from the Fundação Para a Ciência e Tecnologia, Portugal.info:eu-repo/semantics/publishedVersio

Elemental Abundances of Kepler Objects of Interest in APOGEE. I. Two Distinct Orbital Period Regimes Inferred from Host Star Iron Abundances

The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has observed $\sim$600 transiting exoplanets and exoplanet candidates from \textit{Kepler} (Kepler Objects of Interest, KOIs), most with $\geq$18 epochs. The combined multi-epoch spectra are of high signal-to-noise (typically $\geq$100) and yield precise stellar parameters and chemical abundances. We first confirm the ability of the APOGEE abundance pipeline, ASPCAP, to derive reliable [Fe/H] and effective temperatures for FGK dwarf stars -- the primary \textit{Kepler} host stellar type -- by comparing the ASPCAP-derived stellar parameters to those from independent high-resolution spectroscopic characterizations for 221 dwarf stars in the literature. With a sample of 282 close-in ($P<100$ days) KOIs observed in the APOGEE KOI goal program, we find a correlation between orbital period and host star [Fe/H] characterized by a critical period, $P_\mathrm{crit}$= $8.3^{+0.1}_{-4.1}$ days, below which small exoplanets orbit statistically more metal-enriched host stars. This effect may trace a metallicity dependence of the protoplanetary disk inner-radius at the time of planet formation or may be a result of rocky planet ingestion driven by inward planetary migration. We also consider that this may trace a metallicity dependence of the dust sublimation radius, but find no statistically significant correlation with host $T_\mathrm{eff}$ and orbital period to support such a claim.Comment: 18 Pages, Accepted to A

Actinobacteria from arctic and atlantic deep-sea sediments—biodiversity and bioactive potential

The deep-sea covers over 70% of the Earth’s surface and harbors predominantly uncharacterized bacterial communities. Actinobacteria are the major prokaryotic source of bioactive natural products that find their way into drug discovery programs, and the deep-sea is a promising source of biotechnologically relevant actinobacteria. Previous studies on actinobacteria in deep-sea sediments were either regionally restricted or did not combine a community characterization with the analysis of their bioactive potential. Here we characterized the actinobacterial communities of upper layers of deep-sea sediments from the Arctic and the Atlantic (Azores and Madeira) ocean basins, employing 16S rRNA metabarcoding, and studied the biosynthetic potential of cultivable actinobacteria retrieved from those samples. Metabarcoding analysis showed that the actinobacterial composition varied between the sampled regions, with higher abundance in the Arctic samples but higher diversity in the Atlantic ones. Twenty actinobacterial genera were detected using metabarcoding, as a culture-independent method, while culture-dependent methods only allowed the identification of nine genera. Isolation of actinobacteria resulted on the retrieval of 44 isolates, mainly associated with Brachybacterium, Microbacterium, and Brevibacterium genera. Some of these isolates were only identified on a specific sampled region. Chemical extracts of the actinobacterial isolates were subsequently screened for their antimicrobial, anticancer and anti-inflammatory activities. Extracts from two Streptomyces strains demonstrated activity against Candida albicans. Additionally, eight extracts (obtained from Brachybacterium, Brevibacterium, Microbacterium, Rhodococcus, and Streptomyces isolates) showed significant activity against at least one of the tested cancer cell lines (HepG2 and T-47D). Furthermore, 15 actinobacterial extracts showed anti-inflammatory potential in the RAW 264.4 cell model assay, with no concomitant cytotoxic response. Dereplication and molecular networking analysis of the bioactive actinobacterial extracts showed the presence of some metabolites associated with known natural products, but one of the analyzed clusters did not show any match with the natural products described as responsible for these bioactivities. Overall, we were able to recover taxonomically diverse actinobacteria with different bioactivities from the studied deep-sea samples. The conjugation of culture-dependent and -independent methods allows a better understanding of the actinobacterial diversity of deep-sea environments, which is important for the optimization of approaches to obtain novel chemically-rich isolates.info:eu-repo/semantics/publishedVersio

Effects of Chlorella vulgaris as a feed ingredient on the quality and nutritional value of weaned piglets' meat

Chlorella vulgaris (CH) is usually considered a feed supplement in pig nutrition, and its use as an ingredient is poorly studied. Among many interesting characteristics, this microalga has high protein levels and can be a putative alternative for soybean meal. Our aim was to study the effect of a 5% CH incorporation in the diet, individually or combined with two carbohydrases, on meat quality traits and nutritional value. Forty-four post-weaned male piglets individually housed, with an initial live weight of 11.2 0.46 kg, were randomly distributed into four experimental groups: control (n = 11, without CH) and three groups fed with 5% CH incorporation, plain (n = 10), with 0.005% Rovabio® Excel AP (n = 10), and with 0.01% of a pre-selected four-CAZyme mixture (n = 11). After two weeks of trial, piglets were slaughtered and longissimus lumborum collected. CH had no effect on piglets’ growth performance. In turn, incorporation of CH improved the nutritional value of meat by increasing total carotenoids and n-3 PUFA content, thus contributing to a more positive n-6/n-3 fatty acid ratio. The supplementation with Rovabio® benefited tenderness and increased overall acceptability of pork. Our results show beyond doubt the viability of the utilization of this microalga as a feed ingredient for swine productioninfo:eu-repo/semantics/publishedVersio