454 research outputs found

    Bioprospecting and characterization of poly-bhydroxyalkanoate (PHAs) producing bacteria isolated from Colombian sugarcane producing areas

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    Bioprospecting for poly-b-hydroxyalkanoate (PHA)-accumulating micro-organisms was carried out in sugarcane growing areas of Colombia. They were isolated in unbalanced culture medium (highcarbon/nitrogen ratio) with sucrose, fructose and glucose used as carbon source. PHAs producing bacteria were identified by staining with Sudan black and solubilising cellular components in sodiumhypochlorite. A arbitrary scale was established (ranging from 1 to 4) for selecting the best strains, acording to growth, staining with Sudan black and solubilising cellular material. 108 isolates rated higher than 2 were obtained by using this scale; 44 of these were selected for evaluating them in a balloon flask for their ability to grow in sucrose. Scheffe’s test grouped the isolates evaluated in the balloon flask for polymer production and productivity. The 6 best isolates were evaluated in a fermenter to determine their kinetic growth profiles, substrate consumption and polymer accumulation. Differential scanning calorimeter (DSC) was used on the recovered polymer for determining fusion temperature and the conclusion was reached that 2 strains accumulated poly--hydroxybutyrate (PHB) and another 4 accumulated hydroxy-butyrate copolymers and other monomer units. These 6 strains were molecularly characterised by partially sequencing the 16s rRNA ribosomal gene, localizing them in 4 clusters on the taxonomic tree

    A Review of ENSO Influence on the North Atlantic. A Non-Stationary Signal

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    ReviewThe atmospheric seasonal cycle of the North Atlantic region is dominated by meridional movements of the circulation systems: from the tropics, where the West African Monsoon and extreme tropical weather events take place, to the extratropics, where the circulation is dominated by seasonal changes in the jetstream and extratropical cyclones. Climate variability over the North Atlantic is controlled by various mechanisms. Atmospheric internal variability plays a crucial role in the mid-latitudes. However, El Niño-Southern Oscillation (ENSO) is still the main source of predictability in this region situated far away from the Pacific. Although the ENSO influence over tropical and extra-tropical areas is related to different physical mechanisms, in both regions this teleconnection seems to be non-stationary in time and modulated by multidecadal changes of the mean flow. Nowadays, long observational records (greater than 100 years) and modeling projects (e.g., CMIP) permit detecting non-stationarities in the influence of ENSO over the Atlantic basin, and further analyzing its potential mechanisms. The present article reviews the ENSO influence over the Atlantic region, paying special attention to the stability of this teleconnection over time and the possible modulators. Evidence is given that the ENSO–Atlantic teleconnection is weak over the North Atlantic. In this regard, the multidecadal ocean variability seems to modulate the presence of teleconnections, which can lead to important impacts of ENSO and to open windows of opportunity for seasonal predictability.We thank the Climatic Research Unit (CRU), the National Centers for Environmental Prediction (NCEP), the Met Office Hadley Centre and the US National Hurricane Center (NHC) for the Land Precipitation, reanalysis, SST and HURDAT2 datasets, respectively. Belen Rodríguez-Fonseca, Roberto Suárez-Moreno, Jorge López-Parages, Iñigo Gómara, Elsa Mohino, Teresa Losada and Antonio Castaño-Tierno are supported by the research projects PREFACE (EUFP7/2007-2013 Grant Agreement 603521) and MULCLIVAR (CGL2012-38923-C02-01-Spanish Ministry of Economy and Competitiveness). Blanca Ayarzagüena is supported by the Natural Environment Research Council (grant number NE/M006123/1). Julián Villamayor is granted through a scholarship from the MICINN—Spanish government (BES-2013-063821

    Mortality due to non-AIDS-defining cancers among people living with HIV in Spain over 18 years of follow-up

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    Purpose: Our aim was to describe non-AIDS-defining cancer (NADC) mortality among people living with HIV (PLWH), to compare it with that of the general population, and to assess potential risk factors. Methods: We included antiretroviral-naive PLWH from the multicentre CoRIS cohort (2004-2021). We estimated mortality rates and standardised mortality ratios (SMRs). We used cause-specific Cox models to identify risk factors. Results: Among 17,978 PLWH, NADC caused 21% of all deaths observed during the follow-up. Mortality rate due to NADC was 1.58 (95%CI 1.36, 1.83) × 1000 person-years and lung and liver were the most frequent cancer-related causes of death. PLWH had 79% excess NADC mortality risk compared to the general population with the highest SMR found for Hodgkin lymphoma, anal and liver cancers. The SMRs decreased with age and were the highest in age groups under 50 years. The most important prognostic factor was low CD4 count, followed by smoking, viral hepatitis and HIV transmission through heterosexual contact or injection drug use. Conclusion: Non-AIDS cancers are an important cause of death among PLWH. The excess mortality related to certain malignancies and the association with immunodeficiency, smoking, and coinfections highlights the need for early detection and treatment of cancer in this population.Purpose: Our aim was to describe non-AIDS-defining cancer (NADC) mortality among people living with HIV (PLWH), to compare it with that of the general population, and to assess potential risk factors. Methods: We included antiretroviral-naive PLWH from the multicentre CoRIS cohort (2004-2021). We estimated mortality rates and standardised mortality ratios (SMRs). We used cause-specific Cox models to identify risk factors. Results: Among 17,978 PLWH, NADC caused 21% of all deaths observed during the follow-up. Mortality rate due to NADC was 1.58 (95%CI 1.36, 1.83) × 1000 person-years and lung and liver were the most frequent cancer-related causes of death. PLWH had 79% excess NADC mortality risk compared to the general population with the highest SMR found for Hodgkin lymphoma, anal and liver cancers. The SMRs decreased with age and were the highest in age groups under 50 years. The most important prognostic factor was low CD4 count, followed by smoking, viral hepatitis and HIV transmission through heterosexual contact or injection drug use. Conclusion: Non-AIDS cancers are an important cause of death among PLWH. The excess mortality related to certain malignancies and the association with immunodeficiency, smoking, and coinfections highlights the need for early detection and treatment of cancer in this population.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was supported by CIBER -Consorcio Centro de Investigación Biomédica en Red- (CB21/13/00091), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea – NextGenerationEU, the Gilead Scholarship Program for Biomedical Research (GLD19_00106) and the ISCIII- Miguel Servet CP19CIII—00002 contract.S

    Use of Schizosaccharomyces strains for wine fermentation? Effect on the wine composition and food safety

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    Schizosaccharomyceswas initially considered as a spoilage yeast because of the production of undesirable metabolites such as acetic acid, hydrogen sulfide, or acetaldehyde, but it currently seems to be of great value in enology.o ced Nevertheless, Schizosaccharomyces can reduce all of the malic acid in must, leading to malolactic fermentation. Malolactic fermentation is a highly complicated process in enology and leads to a higher concentration of biogenic amines, so the use of Schizosaccharomyces pombe can be an excellent tool for assuring wine safety. Schizosaccharomyces also has much more potential than only reducing the malic acid content, such as increasing the level of pyruvic acid and thus the vinylphenolic pyranoanthocyanin content. Until now, few commercial strains have been available and little research on the selection of appropriate yeast strains with such potential has been conducted. In this study, selected and wild Sc. pombe strains were used along with a Saccharomyces cerevisiae strain to ferment red grape must. The results showed significant differences in several parameters including non-volatile and volatile compounds, anthocyanins, biogenic amines and sensory parameters

    Small-scale solar magnetic fields

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    As we resolve ever smaller structures in the solar atmosphere, it has become clear that magnetism is an important component of those small structures. Small-scale magnetism holds the key to many poorly understood facets of solar magnetism on all scales, such as the existence of a local dynamo, chromospheric heating, and flux emergence, to name a few. Here, we review our knowledge of small-scale photospheric fields, with particular emphasis on quiet-sun field, and discuss the implications of several results obtained recently using new instruments, as well as future prospects in this field of research.Comment: 43 pages, 18 figure

    Diastereoselective Synthesis of C60/Steroid Conjugates

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    The design and synthesis of fullerene–steroid hybrids by using Prato’s protocol has afforded new fullerene derivatives endowed with epiandrosterone, an important naturally occurring steroid hormone. Since the formation of the pyrrolidine ring resulting from the 1,3-dipolar cyloaddition reaction takes place with generation of a new stereogenic center on the C2 of the five-membered ring, the reaction proceeds with formation of a diastereomeric mixture [compounds 6 and 7 in 70:30 ratio, 8 and 9 in 26:74 ratio (HPLC)] in which the formation of the major diasteroisomers 6 and 9 is consistent with an electrophilic attack of [60]fullerene on the Re face of the azomethine ylide directed by the steroidic unit. The chiroptical properties of these conjugates reveal typical Cotton effects in CD spectra that have been used to assign the absolute configuration of the new fulleropyrrolidines. The electrochemical study of the new compounds reveals the presence of four quasi-reversible reduction waves which are cathodically shifted in comparison with the parent C60, thus ascertaining the proposed structures.Financial support by the Ministerio de Ciencia e Innovación (MINECO) of Spain (CTQ2011-24652, CTQ2011-27253, PIB2010JP-00196, and CSD2007-00010 projects) and CAM (Madrisolar-2) is acknowledged; A.R. thanks UCM for financial support; M.S. is indebted to Programa del Grupo Santander 2012

    European stakeholders’ visions and needs for stormwater in future urban drainage systems

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    Transitioning urban drainage systems to serve water-smart societies requires the involvement of different disciplines and stakeholders. However, stakeholders have different visions and needs from the transitioning process (e.g in terms of financing, policy adaptation and system management) these also vary between regions and countries. Identifying such different needs for stakeholders is necessary to propose practical adaptation strategies. Therefore, evidence of needs as reflected in policy papers and legislation in seven European countries was collected. Knowledgeable individuals in the urban drainage community were asked about their visions. Results show that whilst there is consensus on the challenges, visions on how to transition are diverse, indicating that more interaction between the different stakeholder groups is required to develop consensus. Additionally, organisational and legislative structures often slow down the necessary change processes

    Magnetic fields inferred by Solar Orbiter: A comparison between SO/PHI-HRT and SDO/HMI

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    The High Resolution Telescope (HRT) of the Polarimetric and Helioseismic Imager on board the Solar Orbiter spacecraft (SO/PHI) and the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) both infer the photospheric magnetic field from polarised light images. SO/PHI is the first magnetograph to move out of the Sun--Earth line and will provide unprecedented access to the Sun's poles. This provides excellent opportunities for new research wherein the magnetic field maps from both instruments are used simultaneously. We aim to compare the magnetic field maps from these two instruments and discuss any possible differences between them. We used data from both instruments obtained during Solar Orbiter's inferior conjunction on 7 March 2022. The HRT data were additionally treated for geometric distortion and degraded to the same resolution as HMI. The HMI data were re-projected to correct for the 33^{\circ} separation between the two observatories. SO/PHI-HRT and HMI produce remarkably similar line-of-sight magnetograms, with a slope coefficient of 0.970.97, an offset below 11 G, and a Pearson correlation coefficient of 0.970.97. However, SO/PHI-HRT infers weaker line-of-sight fields for the strongest fields. As for the vector magnetic field, SO/PHI-HRT was compared to both the 720720-second and 9090-second HMI vector magnetic field: SO/PHI-HRT has a closer alignment with the 9090-second HMI vector. In the weak signal regime (<600< 600 G), SO/PHI-HRT measures stronger and more horizontal fields than HMI, very likely due to the greater noise in the SO/PHI-HRT data. In the strong field regime (600\gtrsim 600 G), HRT infers lower field strengths but with similar inclinations (a slope of 0.920.92) and azimuths (a slope of 1.021.02). The slope values are from the comparison with the HMI 9090-second vector.Comment: 10 pages, 5 figures, accepted for publication in A&A; manuscript is a part of Astronomy & Astrophysics special issue: Solar Orbiter First Results (Nominal Mission Phase
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