Temporal variability of diazotroph community composition in the upwelling region off NW Iberia.

Knowledge of the ecology of N2-fixing (diazotrophic) plankton is mainly limited to oligotrophic (sub)tropical oceans. However, diazotrophs are widely distributed and active throughout the global ocean. Likewise, relatively little is known about the temporal dynamics of diazotrophs in productive areas. Between February 2014 and December 2015, we carried out 9 one-day samplings in the temperate northwestern Iberian upwelling system to investigate the temporal and vertical variability of the diazotrophic community and its relationship with hydrodynamic forcing. In downwelling conditions, characterized by deeper mixed layers and a homogeneous water column, non-cyanobacterial diazotrophs belonging mainly to nifH clusters 1G (Gammaproteobacteria) and 3 (putative anaerobes) dominated the diazotrophic community. In upwelling and relaxation conditions, affected by enhanced vertical stratification and hydrographic variability, the community was more heterogeneous vertically but less diverse, with prevalence of UCYN-A (unicellular cyanobacteria, subcluster 1B) and non-cyanobacterial diazotrophs from clusters 1G and 3. Oligotyping analysis of UCYN-A phylotype showed that UCYN-A2 sublineage was the most abundant (74%), followed by UCYN-A1 (23%) and UCYN-A4 (2%). UCYN-A1 oligotypes exhibited relatively low frequencies during the three hydrographic conditions, whereas UCYN-A2 showed higher abundances during upwelling and relaxation. Our findings show the presence of a diverse and temporally variable diazotrophic community driven by hydrodynamic forcing in an upwelling system

Supramolecular Complexation of Carbon Nanostructures by Crown Ethers

Since their discovery, crown ethers as well as the most recent carbon nanostructures, namely fullerenes, carbon nanotubes, and graphene, have received a lot of attention from the chemical community. Merging these singular chemical structures by noncovalent forces has provided a large number of unprecedented supramolecular assemblies with new geometric and electronic properties whose more representative examples are presented in this Synopsis organized according to the different nature of the carbon nanostructures

Dried blood spots in clinical lipidomics: optimization and recent findings

Dried blood spots (DBS) are being considered as an alternative sampling method of blood collection that can be used in combination with lipidomic and other omic analysis. DBS are successfully used in the clinical context to collect samples for newborn screening for the measurement of specifc fatty acid derivatives, such as acylcarnitines, and lipids from whole blood for diagnostic purposes. However, DBS are scarcely used for lipidomic analysis and investigations. Lipidomic stud ies using DBS are starting to emerge as a powerful method for sampling and storage in clinical lipidomic analysis, but the major research work is being done in the pre- and analytical steps and procedures, and few in clinical applications. This review presents a description of the impact factors and variables that can afect DBS lipidomic analysis, such as the type of DBS card, haematocrit, homogeneity of the blood drop, matrix/chromatographic efects, and the chemical and physi cal properties of the analyte. Additionally, a brief overview of lipidomic studies using DBS to unveil their application in clinical scenarios is also presented, considering the studies of method development and validation and, to a less extent, for clinical diagnosis using clinical lipidomics. DBS combined with lipidomic approaches proved to be as efective as whole blood samples, achieving high levels of sensitivity and specifcity during MS and MS/MS analysis, which could be a useful tool for biomarker identifcation. Lipidomic profling using MS/MS platforms enables signifcant insights into physiological changes, which could be useful in precision medicine.info:eu-repo/semantics/publishedVersio

Conjugated Porphyrin Dimers: Cooperative Effects and Electronic Communication in Supramolecular Ensembles with C60

Two new conjugated porphyrin-based systems (dimers 3 and 4) endowed with suitable crown ethers have been synthesized as receptors for a fullerene-ammonium salt derivative (1). Association constants in solution have been determined by UVvis titration experiments in CH2Cl2 at room temperature. The designed hosts are able to associate up to two fullerene-based guest molecules and present association constants as high as 5 × 108 M‒1 . Calculation of the allosteric cooperative factor for supramolecular complexes [3·12] and [4·12] showed a negative cooperative effect in both cases. The interactions accounting for the formation of the associates are based, firstly, on the complementary ammonium-crown ether interaction and, secondly, on the π−π interactions between the porphyrin rings and the C60 moieties. Theoretical calculations have evidenced a significant decrease of the electron density in the porphyrin dimers 3 and 4 upon complexation of the first C60 molecule, in good agreement with the negative cooperativity found in these systems. This negative effect is partially compensated by the stabilizing C60-C60 interactions that take place in the more stable syn-disposition of [4·12]

Effect of processing conditions on the microstructure, mechanical properties and corrosion behavior of two austenitic stainless steels for bioimplant applications

Hot torsion tests were carried out to simulate the industrial thermomechanical processing of two austenitic steels for bioimplant applications, namely ISO 5832-9 and ASTM F138. The former has Ti, Nb, and V in the composition, being N-rich. However, the latter is Ni-richer and without extra alloying element additions. Special attention was paid to the effect of interpass times, particularly to the soaking temperature, which was reduced to decrease processing times and costs. Optical and electron microscopy, corrosion tests, and hardness measurements were used to characterize the effect of the above processing parameters on both alloys. No significant increase in processing loads was noticed after the reduction of the reheating temperature. This was explained in terms of the balance between partial particles dissolution and the increment in the solute drag effect provided by the elements put into solution. Such an increment in solid solution favored the dynamic recovery process, delaying the dynamic recrystallization one. However, strain-induced precipitation took place at lower temperatures, by using the extra N and Cr delivered to the matrix, and limiting the recrystallization softening. The rolling schedule promoted abundant grain refinement. The final grain size ranged from 2.5 to 11 µm, depending on reheating temperature, interpass time, presence of alloying elements, and N. In general terms, the corrosion resistance of the ISO steel soaked at the lowest temperature (1200 °C) was better than when reheated to the highest one (1250 °C). On the contrary, the F138 steel had worse corrosion behaviorPeer ReviewedPostprint (published version

Vertical zonation of bacterial assemblages attributed to physical stratification during the summer relaxation of the coastal upwelling off Galicia (NW Spain)

Research articleWe combined flow cytometry, CARD-FISH, and 16S rRNA gene tag pyrosequencing to investigate bacterioplankton dynamics along a transect in shelf waters off A Coruña (Galicia, NW Spain). Over five days (16-20th July 2012) we sampled during the relaxation of a summer upwelling pulse, providing an opportunity to examine the impact of pulses of cold nutrient-rich water into coastal microbial communities. The hydrographic conditions, characterized by intense density stratification of surface waters and the presence of a deep chlorophyll maximum (DCM) at 20–30 m, were relatively maintained over the sampling period. Indeed, bacterial abundance and composition displayed low day to day variation. Alpha diversity analysis suggested that species richness and diversity increased from coastal to shelf stations and from the surface down to the coastal DCM, which could be caused by the mixing of upwelled bacteria with the coastal surface waters. SAR11, SAR86, and Roseobacter were the most abundant bacteria detected in the samples by using CARD-FISH. The assemblages observed by pyrosequencing displayed a strong vertical zonation along the transect. Rhodobacteraceae (under class Alphaproteobacteria) and Bacteriodetes dominated the surface waters and decreased during the upwelling pulse, while SAR 86 (under class Gammaproteobacteria), Actinobacteria and SAR11 clade increased their relative abundance at the coastal DCM with upwelling relaxation, particularly at the shelf stations. Bacterial assemblages from surface waters were associated with higher temperature and light conditions, while coastal DCM assemblages were rather associated to salinity, inorganic nutrients and a diatom-bloom leading to high chlorophyll-a. Our findings suggest that the vertical variability in environmental conditions induced by the intense density stratification, the exportation of warmer and less saline surface water from the rias to the adjacent shelf, and the fertilizing effect of recently upwelled water at the deeper layer, determined the composition of distinct bacterial assemblages at the subsurface and DCM layers.XUNTA DE GALICIA (O9MMA 027604PR, 10MMA604024PR), IEO (PROYECTO RADIALES) y PLAN NACIONAL (MODUPLAN CTM2011-24008)Versión del editor2,24

Probing the Interactions of Thiazole Abietane Inhibitors with the Human Serine Hydrolases ABHD16A and ABHD12

Peer reviewe

The polar lipidome of cultured Emiliania huxleyi: a source of bioactive lipids with relevance for biotechnological applications

Polar lipids from microalgae have aroused greater interest as a natural source of omega-3 (n-3) polyunsaturated fatty acids (PUFA), an alternative to fish, but also as bioactive compounds with multiple applications. The present study aims to characterize the polar lipid profile of cultured microalga Emiliania huxleyi using hydrophilic interaction liquid chromatography coupled with high-resolution mass spectrometry (HILIC-MS) and fatty acids (FA) analysis by gas chromatography (GC-MS). The lipidome of E. huxleyi revealed the presence of distinct n-3 PUFA (40% of total FA), namely docosahexaenoic acid (22:6n-3) and stearidonic acid (18:4n-3), which give this microalga an increased commercial value as a source of n-3 PUFA present in the form of polar lipids. A total of 134 species of polar lipids were identified and some of these species, particularly glycolipids, have already been reported for their bioactive properties. Among betaine lipids, the diacylglyceryl carboxyhydroxymethylcholine (DGCC) class is the least reported in microalgae. For the first time, monomethylphosphatidylethanolamine (MMPE) has been found in the lipidome of E. huxleyi. Overall, this study highlights the potential of E. huxleyi as a sustainable source of high-value polar lipids that can be exploited for different applications, namely human and animal nutrition, cosmetics, and pharmaceuticals.FCT/ FCT/MCTES (Portugal) for the financial support to CICECO (UIDB/50011/2020 and 50011/2020), QOPNA (UID/QUI/00062/2019), LAQV-REQUIMTE (UIDB/50006/2020), CESAM (UIDB/50017/2020 and UIDP/50017/2020), RNEM (LISBOA-01-0145-FEDER-402-022125) and CCMAR: (UIDB/04326/2020).info:eu-repo/semantics/publishedVersio

O diálogo necessário entre extensão rural e Agroecologia

The article assumes that rural holds specifics with which it can work other possibilities besides oversizing technology as the only basis for the environmental, social, political and economic development. There is not only one rural society, but rural societies, with their productive specificities linked to the forces of nature and socio-cultural. The approachis focused on the characterization of a new rural as it presupposes the emergence of specific and endogenous forces leading to a global insertion adapted to the local soil and climate needs and socio-economics. The rural extension needs to shape up and get flexibility in the construction process of sustainable development. However, the understanding of sustainability expressed possibilities of retaining aspects geared only to environmental preservation. When considering a new rural with endogenous forces that play key roles in technological advancement and extension intervention, agroecological approach is fundamental. In several plans interact and shape a framework in which it is bio and social diversity, including technological, cultural, political, economic and social aspects. Sustainability, then, implies a breaking of dependence on social actors towards a truly effective participation able to deepen the understanding of reality to a new articulation between research and extension. From this design agroecologicalextension takes on a character of social inclusion and adapted technologies, which affects decisions on public policies in agricultural sciences beyond the production and reproduction needs of the dominant sectors.O artigo parte do pressuposto que o rural detém especificidades com as quais se podem trabalhar outras possibilidades além do superdimensionamento da tecnologia enquanto único embasamento para o desenvolvimento ambiental, social, político e econômico. Não há uma sociedade rural, mas sim sociedades rurais, com suas especificidades produtivas, ligadas às forças da natureza e sócio-culturais. O enfoque está voltado para a caracterização de um novo rural em que se pressupõe a emergência de forças específicas e endógenas que conduza a uma inserção global adaptada às necessidades edafoclimáticas e sócioeconômicas locais. A extensão em ciências agrárias necessita moldar-se e adquirir flexibilidade no processo de construção de projetos de desenvolvimento sustentável. No entanto, o entendimento atual da sustentabilidade expressa possibilidades de reter aspectos voltados apenas à preservação ambiental. Ao se pensar um novo rural com forças endógenas que desempenham papéis fundamentais no avanço tecnológico e na intervenção extensionista, é fundamental uma abordagem agroecológica. Nesta, vários planos interagem e conformam um quadro em que cabe a bio e a sociodiversidade, entre eles aspectos tecnológicos, culturais, políticos, econômicos e sociais. A sustentabilidade, então, implica num rompimento da dependência dos atores sociais na direção de uma participação realmente eficaz, capaz de aprofundar o entendimento da realidade a uma nova articulação entre investigação e extensão. A partir desse delineamento, a extensão agroecológica adquire um caráter de inclusão social e de tecnologias adaptadas, repercutindo nas decisões relativas às políticas públicas em ciências agrárias que ultrapassem as necessidades de produção e reprodução dos setores dominantes