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Imprudent use of MalAvi names biases the estimation of parasite diversity of avian haemosporidians
No full textUnderstanding patterns of biota diversity at the different geographical scales is one of the major challenges of biogeography [1] and macroecology [2], especially for parasites, one of the most diverse groups on earth [3]. The order Haemosporida includes parasites of wildlife which are among the most studied in ecology and evolution [4,5]. In birds, haemosporidians include malaria parasites of the genus Plasmodium and related genera Haemoproteus and Leucocytozoon [6]. These parasites have been extensively studied in bird populations, mainly in Europe and North America, where authors have identified a high genetic diversity of parasites infecting wild bird species [7]. These parasite genera are an excellent study model for understanding the ecology and evolution of parasite–host interactions [7,8] and factors affecting the specificity and generalist strategies of infections.JMdlP was financed by the MICROVEC-PID2020-118205 GB-I00 grant funded by MCIN/AEI/10.13039/501100011033. Additional support derived from the CNS2022-135993 grant of the Ministerio de Ciencia e Innovación (MCIN/AEI/10.13039/501100011033) with funding from European Union NextGenerationEU to JMdlP. JTQ received a Beca de movilidad Resolución Rectoral 144/2024, financed by the Universidad Internacional de Andalucía.Peer reviewe
The Internal Structure of overpressured, Magnetized, Relativistic Jets
No full textThis work presents the first characterization of the internal structure of overpressured, steady superfast-magnetosonic relativistic jets in connection with their dominant type of energy. To this aim, relativistic magnetohydrodynamic simulations of different jet models threaded by a helical magnetic field have been analyzed covering a wide region in the magnetosonic Mach number-specific internal energy plane. The merit of this plane is that models dominated by different types of energy (internal energy: hot jets; rest-mass energy: kinetically dominated jets; magnetic energy: Poynting-flux-dominated jets) occupy well-separated regions. The analyzed models also cover a wide range of magnetizations. Models dominated by the internal energy (i.e., hot models, or Poynting-flux-dominated jets with magnetizations larger than but close to one) have a rich internal structure characterized by a series of recollimation shocks and present the largest variations in the flow Lorentz factor (and internal energy density). Conversely, in kinetically dominated models, there is not much internal or magnetic energy to be converted into kinetic, and the jets are featureless with small variations in the flow Lorentz factor. The presence of a significant toroidal magnetic field threading the jet produces large gradients in the transversal profile of the internal energy density. Poynting-flux-dominated models with high magnetization (≈10 or larger) are prone to be unstable against magnetic pinch modes, which sets limits on the expected magnetization in parsec-scale active galactic nucleus jets or constrains their magnetic field configuration. © 2016. The American Astronomical Society. All rights reserved.We thank José Mª Ibáñez and Alan P. Marscher for valuable comments that helped us to improve the manuscript. J-MM and MP acknowledge financial support from the Spanish Ministerio de Economía y Competitividad (grants AYA2013-40979-P, and AYA2013-48226-C3-2-P) and from the local Valencian Government (Generalitat Valenciana, grant Prometeo-II/2014/069). JLG acknowledges support from the Spanish Ministerio de Economía y Competitividad grant AYA2013-40825-P. Calculations were carried out using the Altix UV1000 supercomputer LluisVives at the University of Valencia.Peer reviewe
The Third Fermi GBM Gamma-Ray Burst Catalog: The First Six Years
No full textNarayana Bhat, P. et al.--Full list of authors: Narayana Bhat, P.; Meegan, Charles A.; von Kienlin, Andreas; Paciesas, William S.; Briggs, Michael S.; Burgess, J. Michael; Burns, Eric; Chaplin, Vandiver; Cleveland, William H.; Collazzi, Andrew C.; Connaughton, Valerie; Diekmann, Anne M.; Fitzpatrick, Gerard; Gibby, Melissa H.; Giles, Misty M.; Goldstein, Adam M.; Greiner, Jochen; Jenke, Peter A.; Kippen, R. Marc; Kouveliotou, Chryssa; Mailyan, Bagrat; McBreen, Sheila; Pelassa, Veronique; Preece, Robert D.; Roberts, Oliver J.; Sparke, Linda S.; Stanbro, Matthew; Veres, Péter; Wilson-Hodge, Colleen A.; Xiong, Shaolin; Younes, George; Yu, Hoi-Fung; Zhang, BinbinSince its launch in 2008, the Fermi Gamma-ray Burst Monitor (GBM) has triggered and located on average approximately two γ-ray bursts (GRBs) every three days. Here, we present the third of a series of catalogs of GRBs detected by GBM, extending the second catalog by two more years through the middle of 2014 July. The resulting list includes 1405 triggers identified as GRBs. The intention of the GBM GRB catalog is to provide information to the community on the most important observables of the GBM-detected GRBs. For each GRB, the location and main characteristics of the prompt emission, the duration, peak flux, and fluence are derived. The latter two quantities are calculated for the 50-300 keV energy band where the maximum energy release of GRBs in the instrument reference system is observed, and also for a broader energy band from 10 to 1000 keV, exploiting the full energy range of GBM's low-energy [Nai[Tl)] detectors. Using statistical methods to assess clustering, we find that the hardness and duration of GRBs are better fit by a two-component model with short-hard and long-soft bursts than by a model with three components. Furthermore, information is provided on the settings and modifications of the triggering criteria and exceptional operational conditions during years five and six in the mission. This third catalog is an official product of the Fermi GBM science team, and the data files containing the complete results are available from the High-Energy Astrophysics Science Archive Research Center. © 2016. The American Astronomical Society. All rights reserved.Support for the German contribution to G.B.M. was provided by the Bundesministerium für Bildung und Forschung (BMBF) via the Deutsches Zentrum für Luft und Raumfahrt (DLR) under contract number 50 QV 0301. A.v.K. was supported by the Bundesministeriums für Wirtschaft und Technologie (BMWi) through DLR grant 50 OG 1101. S.M.B. and O.J.R. acknowledge support from Science Foundation Ireland under grant No. 12/IP/1288. H.F.Y. acknowledges support by the DFG cluster of excellence "Origin and Structure of the universe." A.G. is funded by the NASA Postdoctoral Program through Oak Ridge Associated Universities. The UAH co-authors gratefully acknowledge NASA funding from co-operative agreement NNM11AA01A. C.K. and C.A.W.H. gratefully acknowledge NASA funding through the Fermi GBM project
El compost de alperujo como fuente de bacterias fijadoras de nitrógeno para la elaboración de biofertilizantes
No full textArturo F. Chica Pérez; María del Carmen Gutiérrez Martín; Mª de los Ángeles Martín Santos; José Ángel Siles López. EditorsEste trabajo se ha realizado gracias al proyecto Intramural Especial CSIC (202440E071). Se agradece la financiación de proyectos PID2020-114330GB-I00 (MCIN/AEI/10.13039/501100011033) y PID2021-124007OB-100 (MCIN/AEI/10.13039/501100011033 y “ERDF A way of making Europe”).Peer reviewe
The development of a whole-cell biosensor enabled the identification of agmatine-producing Hafnia spp. in cheese
No full textAgmatine, the decarboxylation product of arginine, is the precursor of putrescine - a harmful biogenic amine (BA) - that can accumulate in dairy products via bacterial metabolism involving the agmatine deiminase (AGDI) pathway. This first requires agmatine be produced via the decarboxylation of arginine and it remains unknown which microorganisms are responsible for this prior decarboxylation step. In addition, agmatine, as other BA, plays different physiological roles including those of co-transmitter and neuromodulator. Preclinical and clinical studies have shown agmatine to have a neuroprotective effect, rendering it of therapeutic interest being agmatine-producing bacteria proposed as psychobiotics. The identification of BA-producing microorganisms is based on the rise in pH due to the consumption of H+ during such decarboxylation reactions. However, in the detection of agmatine-producing microorganisms in cheese, this would lead to false positives since many bacteria possess arginine deiminase activity; this produces ornithine and ammonium from arginine, which also increases the pH. To overcome this problem, a whole-cell biosensor based on a previously developed agmatine-inducible transcription system was designed, and a protocol optimized for the successful identification of agmatine-producing microorganisms in cheese. The application of this protocol in cheese samples allowed for the isolation of agmatine-producing microorganisms identified as Hafnia spp. and unravels, for first time, the capacity of Hafnia paralvei to produce agmatine. This finding evidence the potential role of Hafnia spp. in putrescine accumulation in dairy products.This work forms part of project grant PID2020-112629RB-I00, funded by MCIU/AEI/10.13039/501100011033.Peer reviewe
Vitamin bioaccessibility of foods fermented with riboflavin-overproducing bifidobacteria
No full textTrabajo presentado a la 8th International Conference on Food Digestion, celebrada en Porto (Portugal) del 9 al 11 de abril de 2024.Certain populations worldwide have vitamin deficiencies and thus, manufacturing fermented food matrices with probiotic cultures capable to enrich the content of vitamin, such as riboflavin, in the final product is an appealing alternative to prevent the issues associated with this vitamin deficiency. In our group, several riboflavin-overproducing derivative strains from two parental Bifidobacterium longum subsp. infantis after roseoflavina exposition were generated. The quantification of this vitamin by a HPLC, using a fluorescence detector, showed that the overproducing strains were able to release up to 1,000-fold more amount than the parental ones in culture medium. Two of the riboflavin producing strains, IPLA60012 and IPLA60015, and their corresponding parental ones, IPLA60011 and CECT4551T respectivelly, were used to elaborate fermented drinks based on dairy or almond drink matrices. Overall, dairy matrix showed higher riboflavin concentrations and demonstrated better preservation of the bifidobacterial strains survival upon one month of refrigerated storage than the almond fermented product. IPLA60002 was the strain producing and maintaining the highest vitamin concentration under cold storage (fermented milk: 1.4 ¿0.10 mg/L; fermented almond-beverage 0.34¿0.02 mg/L). Besides, following simulated in vitro static digestion (Infogest protocol) of the biofortified products, between 59.8-84.6 % of the riboflavin present in the fermented foods were recovered, the highest occurring in the dairy matrix fermented with IPLA60012. Additionally, fermented milks also allowed a higher survival rate of the bifidobacteria in the three phases of static digestion than the vegetable-based product. The final percentage of survival was highly dependent on the strain, but IPLA60012 having the best performance. These results set the ground to facilitate the incorporation of riboflavin producing bifidobacterial cultures into fermented matrices. In one hand, biofortified foods can be obtained naturally enriched in riboflavin which is stable and bioaccesible under cold storage. On the other hand, the fermented foods protected bifidobacteria along the gastrointestinal passage which might also allow the in situ (colon) production of riboflavin. Finally, it is worth noting that the biofortified products were manufactured at 37¿C in aerobic conditions, which is a key trait for the application of oxygen-sensitive bifidobacteria.This work was supported by the project PID2021-127362OB-I00 (funded by MCIN/AEI/ 10.13039/501100011033 and by ¿ERDF A way of making Europe) and by AYUD2021-50910 from the autonomic Government of Principado de Asturias (FICYT, supported by FEDER). H. Tamés acknowledges his predoctoral ¿Severo Ochoa¿ fellowship (BP17-55) to the Regional Government of the Principado de Asturias
Evolutionary evidence on oxidative attack of lignin at a solvent-exposed tryptophan in ligninolytic peroxidases
No full textResúmen de la comunicación oral presentada en 7th LignoBiotech international conference . Toulouse 2024 14-17 oct. 2024A key finding to understand lignin biodegradation was the ability of lignin peroxidase (LiP) and versatile peroxidase (VP) to delocalize one oxidation equivalent from the buried heme to a surface tryptophan residue. In this way, the resulting radical is able to interact with the bulky lignin polymer, and transfer electrons to heme using a long-range pathway. The catalytic nature of the surface tryptophan had been demonstrated by directed mutagenesis using simple lignin models, but similar steady-state studies cannot be performed with lignin due to difficulties to estimate initial oxidation rates. However, it is possible to follow electron transfer from soluble (sulfonated) lignins from the “peroxidase side” (i.e. by estimating the constants for enzyme reduction under stopped-flow conditions) as shown in this study. Moreover, the possibility to reconstruct ancestral proteins permits nowadays to directly identify the evolutionary change responsible for every new enzyme property. Here, four LiP ancestors (red path in peroxidase main clade D, Figure left) were resurrected (by sequence
reconstruction, heterologous expression in Escherichia coli, and in vitro activation) and their ability to transfer electrons to lignin were evaluated together with extant Phanerochaete chrysosporium LiP (PC-LiPA). As shown in the Figure (right) a relationship exists between the rate-limiting constant in lignin reactions (k3app from above stopped-flow analyses) and the presence of the catalytic tryptophan in AVPd, ALiP and PC-LiPA (absent from the previous CaPo and CaD ancestors). [1] This correlation was stronger for hardwood lignosulfonate, suggesting that the surface tryptophan was introduced in fungal peroxidases to better act on the more complex lignin developed by angiosperms. The appearance of a surface tryptophan paralleling the increase of peroxidase activity on lignin provides evolutionary evidence on the role of this residue in ligninolysis.Peer reviewe
Advanced wind farm control strategies for enhancing grid support
No full textTrabajo presentado para lograr el título de Doctor por la Universidad Politécnica de Cataluña, Programa de Doctorado en Automática, Robótica y VisiónNowadays, there is rising concern among Transmission System Operators about the declining of system inertia due to the increasing penetration of wind energy, and other renewable energy systems, and the retirements of conventional power plants. On the other hand, by properly operating wind farms, wind generation may be capable of enhancing grid stability and ensuring continued security of power supply. In this doctoral thesis, new control approaches for designing wind farm optimization-based control strategies are proposed to improve the participation of wind farms in grid support, specially in primary frequency support
Organic molecules in the Sheepbed Mudstone, Gale Crater, Mars
Get PDF© 2015. The Authors. The Sample Analysis at Mars (SAM) instrument on board the Mars Science Laboratory Curiosity rover is designed to conduct inorganic and organic chemical analyses of the atmosphere and the surface regolith and rocks to help evaluate the past and present habitability potential of Mars at Gale Crater. Central to this task is the development of an inventory of any organic molecules present to elucidate processes associated with their origin, diagenesis, concentration, and long-term preservation. This will guide the future search for biosignatures. Here we report the definitive identification of chlorobenzene (150-300 parts per billion by weight (ppbw)) and C2 to C4 dichloroalkanes (up to 70 ppbw) with the SAM gas chromatograph mass spectrometer (GCMS) and detection of chlorobenzene in the direct evolved gas analysis (EGA) mode, in multiple portions of the fines from the Cumberland drill hole in the Sheepbed mudstone at Yellowknife Bay. When combined with GCMS and EGA data from multiple scooped and drilled samples, blank runs, and supporting laboratory analog studies, the elevated levels of chlorobenzene and the dichloroalkanes cannot be solely explained by instrument background sources known to be present in SAM. We conclude that these chlorinated hydrocarbons are the reaction products of Martian chlorine and organic carbon derived from Martian sources (e.g., igneous, hydrothermal, atmospheric, or biological) or exogenous sources such as meteorites, comets, or interplanetary dust particles
Pearls are self-organized natural ratchets
No full textPearls, the most flawless and highly prized of them, are perhaps the most perfectly spherical macroscopic bodies in the biological world. How are they so round? Why are other pearls solids of revolution (off-round, drop, ringed pearl), and yet others have no symmetry (baroque pearls)? We observe that with a spherical pearl the growth fronts of nacre are spirals and target patterns distributed across its surface, and that this is true for a baroque pearl, too, but that in pearls with rotational symmetry spirals and target patterns are found only in the vicinity of the poles; elsewhere the growth fronts are arrayed in ratchet fashion around the equator. We argue that pearl rotation is a self-organized phenomenon caused and sustained by physical forces from the growth fronts, and that rotating pearls are an example - perhaps unique - of a natural ratchet