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Supporting information: Theta oscillations optimize a speed-precision trade-off in phase coding neurons
No full textS1 Appendix. Full derivation of the mean phase of firing.Provides a detailed solution to the deterministic part of Eq 1, resulting in the “rate-to-phase” transfer function (Eq 3) previously derived in [6].S2 Appendix. Full derivation of the variance of phase of firing. Explains the use of a first-order Taylor series expansion and the propagation of uncertainty around the spike threshold to derive an analytical approximation of the phase variance.S3 Appendix. Approximation of information rate. Describes the approximation of the entropy of Gaussian mixtures to derive an analytical estimation of the information rate. Additionally, it introduces a correction factor to account for cycle-to-cycle correlations.S4 Appendix. Neuron parameters. Includes: Table A. Default parameters for hippocampal neurons; Table B. Neuron parameters along the hippocampal dorsoventral axis; Table C. Neuron parameters for visual and olfactory cells. -- S5 Appendix. Simulations. Details the numerical integration of Eq 1 used in simulations supporting our theoretical framework.S1 Fig. Oscillatory frequency modulates the tonic input range that makes neurons phase-lock. (A) Phase-locking function for different values of the oscillatory frequency f (color coded). Shaded areas denote the phase-locking range of Is, corresponding to the domain of Is in Eq 3. The parameters are the same ones used in [6] and in Fig 1, to match hippocampal physiology (described in Table A in Appendix). Note that the phase-locking range spans half of a cycle and not the full cycle as previously thought, in agreement with recent studies [7]. (B) Length of Is range (max(Is) − min(Is) = 2AIosc) across frequencies. (C) Average Is as (middle point in Is range) across frequencies. (D) Effective amplitude of the membrane potential oscillation, Vosc produced by the oscillatory input Iosc. Given that the membrane acts as a low-pass filter, determined by τm, the effective oscillation in the membrane potential can be found to be Vosc = RmIoscA. Thus, since the membrane filters the oscillatory input as , the amplitude of the membrane potential Vosc will decrease with f approximately as ∼ 1/f.S2 Fig. Analytical approximation of phase distributions. (A) Phase distributions for a range of frequencies and noise strengths. Histograms denote the simulations whereas solid lines denote the theoretical predictions. For the simulations, first-spike phases are recorded from the beginning of the second cycle (with the trough as ϕ = 0), after initializing the neurons to their expected phase ϕ0 = μϕ to allow them to reach steady-state dynamics (as described in Appendix). The parameters used here are described in Table A in Appendix). (B) Average variance in rad2 (across Is levels) across a wide frequency–noise parameter space, for simulations and the theoretical predictions. (C) Diagonal slices of plots in (B), showing the deviation of the theory from the simulations after a certain level of noise amplitudes at high frequencies, due to the bounded variance of simulated spike phases constrained to the measurable range of [0, 2π] radians.S3 Fig. Effective rhythmic input sampling. (A) An example signal with τs of 100 ms sampled by different oscillation frequencies. (B) Effective frequency for various τs values.S4 Fig. Information rate across frequencies for the range of physiologically realistic noise levels (η).S5 Fig. Normalized information rate across the frequency–noise parameter space for simulations and theoretical predictions.S6 fig. Normalized information rate across the frequency–noise parameter space for a wide range of input signal time constants τs.S7 Fig. Normalized information rate across the frequency–noise parameter space for a wide range of membrane time constants τm.S8 Fig. Optimal frequency for a wide range of membrane time constants τm and input signal time constants τs. At every point of the τm − τs parameter space (logarithmically discretized in a 200 × 200 grid), we computed rnorm over the frequency–noise space (as in e.g., Fig 4B). Then, the optimal frequency was estimated as an average of the peak frequency between the physiologically-realistic noise range η = [0.1, 0.15].S9 Fig. Normalized information rate for colored noise with different long-range correlation lengths: White, pink, and brown noise.A value of 100 ms was used here for τs. All plots represent the results of simulations.S10 Fig. Normalized information rate across the dorsoventral axis for simulations and theoretical predictions.S11 Fig. Normalized information rate across the frequency-amplitude space for simulations and theoretical predictions.Peer reviewe
Chemical enrichment in LINERs from MaNGA: I. Tracing the nuclear abundances of oxygen and nitrogen in LINERs with varied ionizing sources
No full textContext. The chemical enrichment in low-ionization nuclear emission-line regions (LINERs) is still an issue with spatial resolution spectroscopic data because we lack studies and because the nature of their ionizing source is uncertain, although they are the most abundant type of active galaxies in the nearby Universe.Aims. Considering different scenarios for the ionizing source (hot old stellar populations, active galactic nuclei, or inefficient accretion disks), we analyze the implications of these assumptions to constrain the chemical content of the gas-phase interstellar medium.Methods. We used a sample of 105 galaxies from the survey called Mapping Nearby Galaxies at Apache Point Observatory (MaNGA), whose nuclear central spaxels show LINER-like emission. For each scenario we considered, we built a grid of photoionization models (4928 models for each considered ionizing source) that were later used in the open-source code HII-CHI-MISTRY. This allowed us to estimate chemical abundance ratios such as 12+log(O/H) or log(N/O) and to constrain the ionization parameters that characterize the ionized interstellar medium in these galaxies.Results. The oxygen abundances in the nuclear region of LINER-like galaxies are spread over a wide range 8.08 < 12+log(O/H) < 8.89, with a median solar value (in agreement with previous studies) when models for active galactic nuclei are considered. Nevertheless, the nitrogen-to-oxygen ratio we derived is much less affected by the assumptions on the ionizing source and indicates suprasolar values (log(N/O) = −0.69). By comparing the different scenarios, we show that if hot old stellar populations caused the ionization of the interstellar medium, a complex picture (e.g., outflows and/or inflows that scale with the galaxy chemical abundance) would be needed to explain the chemical enrichment history, whereas the assumption of active galactic nucleus activity is compatible with the standard scenario that is found in most galaxies. © The Authors 2025We acknowledge support from the Spanish MINECO grant PID2022-136598NB-C32. We acknowledge financial support from the Severo Ochoa grant CEX2021-001131-S MICIU/AEI/10.13039/501100011033. This research made use of ASTROPY, which is a community-developed core Python package for Astronomy (Astropy Collaboration 2013, 2018, 2022), and other software and packages: NUMPY (van der Walt et al. 2011), and SCIPY (Virtanen et al. 2020). The plots for this research were created using MATPLOTLIB (Hunter 2007). We acknowledge the fruitful discussions with our research team. We thank the anonymous referee for the constructive report that improved this manuscript. E.P.M. acknowledges the assistance from his guide dog, Rocko, without whose daily help this work would have been much more difficult.With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).Peer reviewe
Precise measurement of nuclear interaction cross sections towards neutron-skin determination with R3B
Get PDF5 pages, 2 figuresThe R3B (Reactions with Relativistic Radioactive Beams) experiment as a major instrument of the NUSTAR collaboration for the research facility FAIR in Darmstadt is designed for kinematically complete studies of reactions with high-energy radioactive beams. Part of the broad physics program of R3B is to constrain the asymmetry term in the nuclear equation-of-state and hence improve the description of highly asymmetric nuclear matter (e.g., in neutron stars). For a precise determination of the neutron-skin thickness – an observable which is directly correlated with the symmetry energy in theoretical calculations – by measuring absolute fragmentation cross sections, it is essential to quantify the uncertainty and challenge the reaction model under stable conditions. During the successful FAIR Phase-0 campaign of R3B, we precisely measured the energy dependence of total interaction cross sections in 12C+12C collisions, for a direct comparison with calculations based on the eikonal reaction theory.The project was supported by BMBF 05P21WOFN1, 05P19WOFN1, 05P21RDFN2, 05P19RDFN1, HFHF (“Helmholtz Forschungsakademie Hessen für FAIR”) and funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC 2094 – 390783311 and the GSI-TU Darmstadt cooperation agreement. C.A.B. acknowledges support by the U.S. DOE grant DE-FG02-08ER41533. This work has been partly supported by the Spanish Funding Agency for Research (AEI) through Projects No. PGC2018-099746-B-C21, PGC2018-099746-B-C22, PID2019-104390GB-I00, PID2021-125771NB-C21, PID2021-125771NB-C22 and PID2022-140162NB-I00. J. Park acknowledges the support by the Institute for Basic Science (IBS-R031-D1). I.G., A.H, D.J.M. and I.L. have been supported by Croatian Science Foundation (HRZZ) under project no. 1257. Supported by Portuguese FCT Project EXPL/FIS-NUC/0364/2021. J.L.R.S. thanks the support from Xunta de Galicia under the program of postdoctoral fellowships ED481B2017-002 and ED481D-2021-018, and by the Grant No. RYC2021-031989-I. T.A., Y.A.L, and A.O. thank the State of Hesse within the Research Cluster ELEMENTS through project ID 500/10.006. Support by the Swedish Research Council under Contract No. 202204248, 2014-06644-VR and 2021-04576-VR. This research was supported in part by the ExtreMe Matter Institute EMMI at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. This work was supported by the Royal Society and the UK STFC under grant numbers ST/L005727/1, ST/P003885/1 and ST/V001035/1. M.F.F thanks the support from Xunta de Galicia with the Grant No. ED481A-2023-049 under the program of predoctoral fellowships.Peer reviewe
A Theoretical Analysis of the 19F NMR Spectrum of 5-(Perfluoroethyl)-3,4,5-tris(trifluoromethyl)pyrazolidin-3-ol
No full textThe H and F spectra of 5-(perfluoroethyl)-3,4,5-tris(trifluoromethyl)-pyrazolidin-3-ol reported unassigned in the literature were compared with GIAO/ B3LYP/6-311++G(d,p) calculations for the different isomers and conformers, the latter structures were searched using the CREST program. The signal assignment corresponds to the 3S,4R,5R or 3R,4S,5S diastereoisomers.This work was carried out with financial support from the Ministerio de Ciencia, Innovación y Universidades (PID2021-125207NB-C32). Thanks are also given to the CTI (CSIC) for their continued computational suppor
Impact of hypercholesterolemia on hepatic fatty acid metabolism in the hallmark of diabetes: Studies from in vivo models
No full textTrabajo fin de máster presentado en la Universidad Autónoma de Barcelona, Official Master's Degree Translational Biomedical Researc
Organophosphate ester flame retardants in sediments and marine fish species in Colombia: Occurrence, distribution, and implications for human risk assessment
No full textExposure to organophosphate esters (OPEs) remains a significant concern, especially in aquatic systems where these compounds can bioaccumulate in organisms. However, limited information exists regarding their potential health risks to humans through the food web in tropical ecosystems. This study investigated the levels, bioaccumulation, and trophic transfer of OPEs in sediments and marine fish species from Cartagena and Barbacoas bays, Colombia. Twenty target OPEs were quantified in sediments and fish. The average concentrations of ∑18OPEs in sediments ranged from 2.80 to 115 ng/g dry weight (dw), while ∑20OPE concentrations in fish ranged from 212 to 1968 ng/g lipid weight (lw), with the highest concentrations found in carnivorous species. Trophic magnification factors (TMF) for OPEs varied from 11.0 to 25.8 for compounds such as 2-ethylhexyl diphenyl phosphate (EHDPP), 4-isopropylphenyl diphenyl phosphate (4IPPDPP), tris(2-isopropylphenyl) phosphate (T2IPPP), and tricresylphosphate (TCP), indicating their potential for biomagnification within the marine food web. Biota-sediment accumulation factors (BSAF) for ∑11OPEs ranged from 0.340 to 4.32, showing a significant Spearman correlation with log Kow in fish: Pargo chino (r = -0.78, p < 0.05), Mojarra blanca (r = 0.79, p < 0.05), and Lisa (r = 0.72, p < 0.05). This suggests that bioaccumulation and biomagnification of certain OPEs in fish increase with the lipophilicity of these compounds. Despite these findings, the potential human health risk from OPE exposure via fish consumption was found to be minimal.The authors would like to thank the Ministry of Science, Technology, and Innovation (MinCiencias) and the Sistema General de Regalías in Colombia for supporting this study through grant BPIN-2020000100427 (Gobernaciones de Atlántico, Bolívar, Cesar, Córdoba, La Guajira, Magdalena, Sucre, and San Andrés y Providence). This study was supported by the Generalitat de Catalunya – Consolidated Research Group Environmental and Water Chemistry for Human Health 2021 SGR 01150.Peer reviewe
Fermi GBM Observations of LIGO Gravitational-wave Event GW150914
No full textConnaughton, V. et al.--Full list of authors: Connaughton, V.; Burns, E.; Goldstein, A.; Blackburn, L.; Briggs, M. S.; Zhang, B. -B.; Camp, J.; Christensen, N.; Hui, C. M.; Jenke, P.; Littenberg, T.; McEnery, J. E.; Racusin, J.; Shawhan, P.; Singer, L.; Veitch, J.; Wilson-Hodge, C. A.; Bhat, P. N.; Bissaldi, E.; Cleveland, W.; Fitzpatrick, G.; Giles, M. M.; Gibby, M. H.; von Kienlin, A.; Kippen, R. M.; McBreen, S.; Mailyan, B.; Meegan, C. A.; Paciesas, W. S.; Preece, R. D.; Roberts, O. J.; Sparke, L.; Stanbro, M.; Toelge, K.; Veres, P.With an instantaneous view of 70% of the sky, the Fermi Gamma-ray Burst Monitor (GBM) is an excellent partner in the search for electromagnetic counterparts to gravitational-wave (GW) events. GBM observations at the time of the Laser Interferometer Gravitational-wave Observatory (LIGO) event GW150914 reveal the presence of a weak transient above 50 keV, 0.4 s after the GW event, with a false-alarm probability of 0.0022 (2.9σ). This weak transient lasting 1 s was not detected by any other instrument and does not appear to be connected with other previously known astrophysical, solar, terrestrial, or magnetospheric activity. Its localization is ill-constrained but consistent with the direction of GW150914. The duration and spectrum of the transient event are consistent with a weak short gamma-ray burst (GRB) arriving at a large angle to the direction in which Fermi was pointing where the GBM detector response is not optimal. If the GBM transient is associated with GW150914, then this electromagnetic signal from a stellar mass black hole binary merger is unexpected. We calculate a luminosity in hard X-ray emission between 1 keV and 10 MeV of erg s. Future joint observations of GW events by LIGO/Virgo and Fermi GBM could reveal whether the weak transient reported here is a plausible counterpart to GW150914 or a chance coincidence, and will further probe the connection between compact binary mergers and short GRBs. © 2016. The American Astronomical Society. All rights reserved.The authors acknowledge an ongoing collaborative effort and significant contributions to this paper from the LIGO/Virgo Consortium. They thank Marica Branchesi for her co-leadership of the LIGO/Virgo electromagnetic follow-up group, for providing prompt alerts and other information pertaining to the GW event. The GBM project is supported by NASA. Support for the German contribution to GBM 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. A.G. and L.S. are funded through the NASA Postdoctoral Fellowship Program. O.J.R. acknowledges support from Science Foundation Ireland under grant No. 12/IP/1288. J.V. was supported by STFC grant, ST/K005014/1. N.C. acknowledges NSF grant, PHY-1505373. The authors wish to thank the World Wide Lightning Location Network (http://wwlln.net), a collaboration among over 50 universities and institutions, for providing the lightning location data used in this paper. The authors are grateful to Sylvia Zhu for a critical reading of the manuscript and for her helpful suggestions
The margins between the islands of Tenerife and Gran Canaria integrating seismic and seabed observations: Guanche project
No full textXI Congreso Geológico de España, 2-6 de julio 2024, Ávila.-- 1 page[EN] The primary objective of the Guanche project is to characterize the seismicity and subsurface structure within the Tenerife-Gran Canaria-Fuerteventura region. To achieve this, an oceanographic survey was conducted in early 2024 to acquire passive seismic waves at sea, deploying a temporary network of 17 ocean bottom seismometers provided by UTM-CSIC and GEOMAR (Germany) combined with land seismometers deployed by the National Geographic Institute. Additionally, strain data using an existing submarine telecommunication cable (DAS, Distributed Acoustic Sensing) was collected. During the survey, a 14,700 km2 multibeam bathymetric mosaic was acquired, processed by the Spanish Institute of Oceanography (IEO), and 677 km of ultra-high resolution seismic lines using a parametric sediment profiler (Topas). Preliminary results from the Tenerife-Gran Canaria area indicate the development of a complex drainage system formed by canyons and corridors embedded in avalanche debris deposits formed in the margins of both islands where several fossil and recent scars are observed. This drainage system is divided into two slopes by a topographic threshold in an NE-SW direction, at the apex of which the Enmedio volcano, the largest, is located and most of the seismicity is concentrated. Among all the active structures observed, recent measurements have revealed the presence of NNE-SSW oriented faults in the northern region of Gran Canaria, exhibiting offsets of metric scale. Additionally, a comprehensiveanalysis has been conducted on the Santa Cruz fault, which extends along the coastline dipping ENEWSW, offshore of the city bearing the same name[ES] El objetivo del proyecto Guanche (PID2020-114682RB-C31) es caracterizar la sismicidad y la estructura del subsuelo en la región comprendida entre Tenerife-Gran Canaria-Fuerteventura. Para ello se realizó una campaña oceanográfica a principios del año 2024 parar registrar terremotos mediante 17 sismógrafos en el fondo oceánico (UTM-CSIC y GEOMAR), complementados con otros desplegados en tierra por el Instituto Geográfico Nacional y con la instalación de dos interrogadores DAS (Distributed Acoustic Sensing) en un cable submarino de telecomunicaciones. Durante la campaña se registró un mosaico batimétrico multihaz de 14.700 km2, procesado por el Instituto Español de Oceanografía, y 677 km de líneas sísmicas de ultra alta resolución con un perfilador paramétrico de sedimentos (Topas). Los datos preliminares de la zona Tenerife-Gran Canaria indican el desarrollo de un complejo sistema de drenaje formado por cañones y corredores encajados sobre depósitos de debris en avalancha originados en los márgenes de ambas islas donde se observan varias cicatrices fósiles y recientes. Este sistema de drenaje queda dividido en dos vertientes por un umbral topográfico de dirección NE-SO en cuyo vértice se sitúa el volcán submarino de Enmedio, donde se concentra mayoritariamente la sismicidad. Se constata la existencia de fallas recientes orientadas NNE-SSO al norte de Gran Canaria con saltos de orden métrico y se ha caracterizado en detalle la falla de Santa Cruz, de salto en dirección ENE-OSO, en la costa este de Tenerife, cerca de la ciudad del mismo nombreWith the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S
Amino Acid Composition, Antioxidant and Antihypertensive Activity in Extracts from Mexican Añejo Cheese
No full text11 Páginas.-- 2 Figuras.-- 6 TablasResearch background. Authentic Mexican cheeses have potential health benefits, although there are few studies on their bioactive components. In this study, we analysed soluble extracts from añejo cheese from Zacazonapan (Mexico), obtained from two dairies (A and B) that used milk from cows of different breeds and differed in processing. Experimental approach. The soluble extracts of Zacazonapan añejo cheese during ripening (0, 30, 95 and 180 days) were used to determine proximate composition, amino acid composition, peptide profile, molecular mass profile, antioxidant and antihypertensive activities. Results and conclusions. The molecular mass of the released protein fragments ranged from 0.10 to 22.43 kDa. During ripening, amino acids such as Pro, His, Tyr, Trp, Met, Cys, Ala, Gly, Leu and Val were present, which are associated with antioxidant activity. The inhibition of β-carotene bleaching was below 50 % at all ripening times. A significant difference between the cheese samples was observed only after 180 days. Amino acids associated with angiotensin-I converting enzyme (ACE-I) inhibition were found in the extracts (Trp, Phe, Tyr, Pro, Lys and Arg). The highest activity was observed in cheese ripened for 180 days (IC of cheese A and B was 0.38 and 0.42 mg/mL, respectively). Novelty and scientific contribution. These results suggest that Zacazonapan añejo cheese is a potential source of antioxidant and antihypertensive peptides, which are influenced by the dairy factor (milk source and production technique) and ripening time. This is relevant as there are no reports of these bioactivities in this type of cheese.Project was funded by the Universidad Autonóma Chapingo (Chapingo Autonomous University), Texcoco, Mexico, through the Dirección General de Investigación y Posgrado (Directorate General for Research and Postgraduate Studies) and the financial support of the Consejo Nacional de Humanidades, Ciencias y Tecnologías, CONAHCyT (Mexican Ministry of Humanities, Sciences and Technologies Science).Peer reviewe
Biomethanisation of sewage sludge: Sonication pretreatment and monitoring of microbial communities
No full text14 Páginas.-- 7 Figuras.-- 1 TablaThe improvement of mesophilic biomethanisation of recalcitrant sewage sludge derived from urban wastewater treatment through the application of a sonication pretreatment was evaluated in parallel in two pilot-scale anaerobic digesters (two biological replicates: reactors RA and RB). The valorisation process was monitored through a novel and holistic approach that related the biomethanisation yield, and its main batch operational parameters, with the abundance of archaeal and bacterial communities in the anaerobic inocula. Sonication allowed achieving a methane yield coefficient derived from sewage sludge of 240 ± 20 mLCH/g VS (volatile solids) at the load range of 0.8–4.0 g VS/L in both reactors. The process was more stable in reactor B, with a wider range of loads being allowed (up to 5.29 g VS/L). Monitoring the presence of Archaea in the mixing liquor revealed a variation in their abundance throughout the process which was directly related to the availability of organic matter and pH. Advanced metagenomic analysis showed the phylogenetic and functional diversity of the complex microbiome involved. While Bacteria were widely distributed in 35 phyla, Archaea fitted in only two. Euryarchaeota was the majoritarian archaeal phylum (99.5 %) and its more abundant families are linked to methanogenic metabolism. Functional analysis revealed several relevant metabolic pathways that followed similar trends in both reactors. “Methane metabolism” clearly diminished at the end of the process in concordance with the exhaust of methane generation, while “ABC transporters” or “two-component systems”, involved in bacterial survival to changing environments, followed the opposite pattern. This integrated approach could help to increase the methanogenic valorisation of sewage sludge.We would like to thank Dr. Mercedes Cousinou and Ms. Laura Redondo (Genomic Unit, SCAI, UCO) for their technical help in metagenomic sequencing. M. Barbudo-Lunar is recipient of a predoctoral contract of the University of Cordoba (“Plan Propio”). We also wish to express our gratitude to Inmaculada Bellido for their contribution to this research as lab technician. We also wish to express our gratitude to Regional Government of Andalusia for funding PAIDI Groups RNM-271 and BIO-187. Funding for open access charge: Universidad de Córdoba / CBUA