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Los científicos tratan de explicar por qué el pez diablo negro emergió del abismo: “Venía huyendo de otro mundo”
No full textEl pez abisal que ha aparecido en aguas de Tenerife ha sido examinado por los biólogos marinos, que manejan varias hipótesis para explicar su inusual ascensión desde las profundidadesPeer reviewe
Helical magnetic field structure in 3C 273 A Faraday rotation analysis using multi-frequency polarimetric VLBA data
No full textWe present a study on rotation measure (RM) of the quasar 3C 273. This analysis aims to discern the magnetic field structure and its temporal evolution. The quasar 3C 273 is one of the most studied active galactic nuclei due to its high brightness, strong polarisation, and proximity, which enables the resolving of the transverse structure of its jet in detail. We used polarised data from 2014, collected at six frequencies (5, 8, 15, 22, 43, 86 GHz) with the Very Long Baseline Array, to produce total and linear polarisation-intensity images, as well as RM maps. Our analysis reveals a well-defined transverse RM gradient across the jet, indicating a helical, ordered magnetic field that threads the jet and likely contributes to its collimation. Furthermore, we identified temporal variations in the RM magnitude when compared with prior observations. These temporal variations show that the environment around the jet is dynamic, with changes in the density and magnetic field strength of the sheath that are possibly caused by interactions with the surrounding medium. © The Authors 2025Author contributions: T. Toscano performed the analysis of total intensity, polarization, and Faraday rotation, and wrote most of the manuscript. J. L. Gómez wrote the observing proposal, prepared the schedule, calibrated the data with Sol M. Molina, contributed to the manuscript, and supervised the analysis. A. Zeng contributed to the rotation measure analysis and manuscript revision. R. Dahale provided scripts for plotting polarization images and commented on the final manuscript. I. Cho, K. Moriyama, M. Wielgus, A. Fuentes, M. Foschi, T. Traianou and J. Röder contributed to the discussion of results and revised the manuscript. I. Myserlis, E. Angelakis, and J. A. Zensus provided EVPA single-dish measurements at 5 and 8 GHz. The work at the IAA-CSIC is supported in part by the Spanish Ministerio de Economía y Competitividad (grants AYA2016-80889-P, PID2019-108995GB-C21, PID2022-140888NB-C21), the Ramón y Cajal grant RYC2023-042988-I from the Spanish Ministry of Science and Innovation, the Consejería de Economía, Conocimiento, Empresas y Universidad of the Junta de Andalucía (grant P18-FR-1769), the Consejo Superior de Investigaciones Científicas (grant 2019AEP112), and the State Agency for Research of the Spanish MCIU through the “Center of Excellence Severo Ochoa” grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033 awarded to the Instituto de Astrofísica de Andalucía.With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).Peer reviewe
Scalable eQTL mapping using single-nucleus RNA-sequencing of recombined gametes from a small number of individuals
No full text29 Paqs.- 7 Figs. Accessible Data: https://github.com/schneebergerlab/snrna_eqtl_mapping. © 2025 Parker et al. This is an open
access article distributed under the terms of
the Creative Commons Attribution License,Phenotypic differences between individuals of a species are often caused by differ ences in gene expression, which are in turn caused by genetic variation. Expression
quantitative trait locus (eQTL) analysis is a methodology by which we can identify
such causal variants. Scaling eQTL analysis is costly due to the expense of generat ing mapping populations, and the collection of matched transcriptomic and genomic
information. We developed a rapid eQTL analysis approach using single-cell/nucleus
RNA sequencing of gametes from a small number of heterozygous individuals.
Patterns of inherited polymorphisms are used to infer the recombinant genomes
of thousands of individual gametes and identify how different haplotypes correlate
with variation in gene expression. Applied to Arabidopsis pollen nuclei, our approach
uncovers both cis- and trans-eQTLs, ultimately mapping variation in a master regula tor of sperm cell development that affects the expression of hundreds of genes. This
establishes snRNA-sequencing as a powerful, cost-effective method for the mapping
of meiotic recombination, addressing the scalability challenges of eQTL analysis and
enabling eQTL mapping in specific cell-types.This work was supported by the
Deutsche Forschungsgemeinschaft (DFG)
through grants EXC 2048/1-390686111 and
Project-ID 456082119 – TRR 341/1 (“Plant
Ecological Genetics”) to KS, and the European
Research Council (ERC) through grant 802629
(“INTERACT”) to KSPeer reviewe
Laia Ribas, en una entrevista de pas
No full texta Laia Ribas Cabezas és una biòloga que treballa a l’Institut de Ciències del Mar (ICM-CSIC) de Barcelona. L’any 2023 va ser una de les tripulants del projecte Hypatia I. Conjuntament amb vuit científiques catalanes més, feu una estada a la Mars Desert Research Station de Utah (Estats Units), un espai en què s’hi reprodueixen les condicions en què podria viure una futura expedició a Mart. Fa unes setmanes fou una de les protagonistes del Febrer Científic que organitza el Servei de Biblioteca municipal, i allà vam poder conèixer la seva experiènciaPeer reviewe
Induced tomato defenses mediated by jasmonic acid do not have a major effect on the density of predator biological control agents
No full textPlants have developed different defense mechanisms to protect themselves from the attack of herbivores. Plant defenses can be categorized into two types: constitutive, which are present before herbivore attack, and induced, which are activated upon attack. Some herbivores have developed the ability to neutralize either or both types of plant defenses, and plant defenses may act against their own interest when they negatively affect herbivore’s natural enemies such predator insects and mites. Here we investigated whether herbivore-induced tomato defenses mediated by jasmonic acid (JA) affect the density of predator biological control agents and thus affect biological pest control negatively. Specifically, we assessed predator–herbivore abundances in greenhouse experiments on two tomato genotypes, a wild type (Castlemart) expressing the JA-mediated defense pathway and a mutant of the wild type (def-1) unable to activate this defense path. Plants were infested with either Bemisia tabaci, a pest that suppresses the activation of the JA defense path, or Frankliniella occidentalis, a pest species that induces JA defenses. As predators, we used four species of natural enemies, two phytoseiid mites and two predatory bugs, one of each pair able to colonize tomato crops (Typhlodromus (A.) recki, Macrolophus pygmaeus) and the other not (Amblyseius swirskii, Orius laevigatus). Results suggest that JA-mediated defenses do not have a negative impact on predator density. Instead, glandular trichomes likely contributed to the unsuccessful pest control. Yet, JA-mediated defenses are key for plant protection against herbivore species that cannot avoid this line of defense.The authors of this work were supported by funds from the European Union’s Horizon 2020 research and innovation program under grant agreement No 773902 —“SuperPests”; and from the Spanish “Agencia Estatal de Investigación”, Project “SPILL-ISLAND”, grant reference PID2019-103863RB-I00. We thank three anonymous reviewers for their suggestions which contributed significantly to improve our manuscriptPeer reviewe
Proyecto de Ciencia Ciudadana RECICOMPHUERTOS: reciclamos el compost de residuos urbanos de recogida selectiva en los huertos urbanos
No full textResumenEl proyecto RECICOMPHUERTOS, que cuenta con la colaboración de la Fundación Española para la Ciencia y la Tecnología (FECYT) del Ministerio de Ciencia, Innovación y Universidades, se enfoca en aprovechar el compost generado a partir de los residuos orgánicos separados
selectivamente en los huertos urbanos. En concordancia con la normativa de la Unión Europea sobre residuos, se promueve la separación específica de los biorresiduos. A través de la iniciativa de Ciencia Ciudadana RECICOMPHUERTOS, se busca destacar los beneficios del compost y promover su uso entre la población, haciendo énfasis en el compost producido a partir de los desechos orgánicos recolectados selectivamente por los ciudadanos. El proyecto implica la realización de diversos ensayos en parcelas de un huerto social en Utrera y en varios huertos
escolares, como el IES Ibn Jaldún de Dos Hermanas y el IES José María Infantes de Utrera, así como otros centros educativos de la misma localidad. Estos ensayos se llevan a cabo siguiendo prácticas de agricultura ecológica, y son ejecutados por personas jubiladas y estudiantes de los centros escolares, supervisados por sus profesores. En esta iniciativa también participan el Ayuntamiento de Utrera, la empresa Agricultura y Ensayo SL, la Universidad de Sevilla y el IRNASCSIC. La colaboración de estos grupos tiene como objetivo principal difundir la metodología
científica relacionada con el compost y su aplicación en la agricultura, alcanzando tanto a los participantes como a la comunidad en general. Entre las actividades planificadas se incluyen talleres experimentales, jornadas de divulgación, preparación de videos informativos y sesiones
de degustación de productos ecológicos. Además, se elaborarán manuales explicativos sobre el uso adecuado del compost en huertos urbanos. Los resultados obtenidos hasta el momento en los ensayos son altamente satisfactorios, demostrando un mayor rendimiento en términos de
peso de las hortalizas cuando se aplicó este compost al suelo. Igualmente, la participación y el entusiasmo de los colectivos implicados muestran el enorme interés de estudiantes, profesores y hortelanos por el proyecto.N
Recicomp huertos: El Proyecto de Ciencia Ciudadana para reciclar compost de biorresiduos en huertos urbanos
No full textEl proyecto RECICOMP-HUERTOS, con la colaboracion por FECYT, promueve el uso de compost procedente de residuos orgánicos urbanos separados selectivamente (biorresiduos) en huertos urbanos, siguiendo la normativa de la UE. A través de la iniciativa de Ciencia Ciudadana,
destaca los beneficios del compost y fomenta su uso. Los ensayos se llevan a cabo en un huerto comunitario de Utrera y en varios huertos escolares, entre ellos el IES Ibn Jaldún (Dos Hermanas) y el IES José María Infantes (Utrera). Estos ensayos siguen prácticas de agricultura ecológica e involucran a jubilados y estudiantes bajo la supervisión de profesores. En el proyecto participan el Ayuntamiento de Utrera, Agricultura y Ensayo SL, la Universidad de Sevilla e IRNAS-CSIC para difundir el conocimiento científico sobre el compost y sus aplicaciones agrícolas. Las actividades incluyen talleres, eventos de divulgación, vídeos educativos y catas de productos orgánicos. También se crearán manuales sobre el uso adecuado del compost en huertos urbanos. Los resultados iniciales muestran un aumento de la producción de hortalizas cuando se aplica
compost, y la fuerte participación de estudiantes, profesores y horticultores demuestra un gran interés en el proyecto.El proyecto RECICOMPHUERTOS (FCT 22-18403) cuenta con la colaboración de la Fundación Española para la Ciencia y la Tecnología (FECYT) del Ministerio de Ciencia, Innovación y Universidades
Insights and simulation of metascintillator-based brain PET systems to enhance ToF capability
No full textThe integration of Time-of-Flight (ToF) information into Positron Emission Tomography (PET) image reconstruction enhances both signal-to-noise ratio and the localization of annihilation events. A critical component contributing to the accuracy of ToF-PET is the scintillator. To overcome the time resolution limitations in conventional scintillators, the metascintillator approach has been proposed. The metascintillator is an engineered composition of small units that combines and optimizes various features within a single scintillator heterostructure.
In this work, metascintillator-based brain PET systems were simulated using the GATE toolkit and compared with designs based on bulk LYSO or BGO. Sensitivity, noise equivalent count rate (NECR) and scatter fraction were evaluated following NEMA guidelines. To match the peak sensitivity of a system utilizing a 15 mm bulk BGO, the metascintillator-based scanners using BGO/BaF2, BGO/EJ232, LYSO/BaF2 and LYSO/EJ232 must possess thicknesses of 23.2 mm, 22.5 mm, 29.7 mm and 31.1 mm, respectively. With ToF gain, the scanner utilizing a 25 mm thick LYSO-EJ232 metascintillator exhibited the most promising NECR curve, peaking at 1180 cps at 1600 MBq. This work takes a significant step towards harnessing the information gain facilitated by the integration of metascintillator-based detectors in PET imaging.This work has been initiated within the framework of a public–private partnership between the Multiwave Metacrystal SA company, based in Geneva (Switzerland), and the Instituto de Instrumentación para Imagen Molecular, Centro Mixto CSIC-UPV, 46022 Valencia (Spain). Their support is greatly acknowledged. Additionally, it has been in part supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 695536): 4D-PET and the Brazilian funding agencies Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq grant agreement No 202378/2020-9 and 435039/2018-0) and Financiadora de Estudos e Projetos, Brazil (FINEP grant agreement No 0294/16). The metascintillator concept presented in this manuscript was based on research first developed within the TICAL: 4D total absorptionTime Imaging CALorimeter ERC (grant agreement no 338953).Peer reviewe
RNA Polymerases IV and V Are Involved in Olive Fruit Development
No full textTranscription is carried out in most eukaryotes by three multimeric complexes (RNA polymerases I, II and III). However, plants contain two additional RNA polymerases (IV and V), which have evolved from RNA polymerase II. RNA polymerases II, IV and V contain both common and specific subunits that may specialise some of their functions. In this study, we conducted a search for the genes that putatively code for the specific subunits of RNA polymerases IV and V, as well as those corresponding to RNA polymerase II in olive trees. Based on the homology with the genes of Arabidopsis thaliana, we identified 13 genes that putatively code for the specific subunits of polymerases IV and V, and 16 genes that code for the corresponding specific subunits of polymerase II in olives. The transcriptomic analysis by RNA-Seq revealed that the expression of the RNA polymerases IV and V genes was induced during the initial stages of fruit development. Given that RNA polymerases IV and V are involved in the transcription of long non-coding RNAs, we investigated their expression and observed relevant changes in the expression of this type of RNAs. Particularly, the expression of the intergenic and intronic long non-coding RNAs tended to increase in the early steps of fruit development, suggesting their potential role in this process. The positive correlation between the expression of RNA polymerases IV and V subunits and the expression of non-coding RNAs supports the hypothesis that RNA polymerases IV and V may play a role in fruit development through the synthesis of this type of RNAs
Additional file 7 of Heterochrony in orthodenticle expression is associated with ommatidial size variation between Drosophila species [Dataset]
No full textAdditional file 7: Table S4. Measurements of plot intensities of otd in situ hybridization in D. mauritiana and D. simulans eye discs.Deutsche Forschungsgemeinschaft Biotechnology and Biological Sciences Research Council Ministerio de Ciencia, Innovación y Universidades European Research CouncilPeer reviewe