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Fermion mass hierarchy in an extended left-right symmetric model
(Springer Science and Business Media Deutschland GmbH, 0023) Bonilla, Cesar; Cárcamo Hernández A.E; Kovalenko, Sergey; Lee H.; Pasechnik R; Schmidt, Ivan
We present a Left-Right symmetric model that provides an explanation for the mass hierarchy of the charged fermions within the framework of the Standard Model. This explanation is achieved through the utilization of both tree-level and radiative seesaw mechanisms. In this model, the tiny masses of the light active neutrinos are generated via a three-loop radiative inverse seesaw mechanism, with Dirac and Majorana submatrices arising at one-loop level. To the best of our knowledge, this is the first example of the inverse seesaw mechanism being implemented with both submatrices generated at one- loop level. The model contains a global U(1) X symmetry which, after its spontaneous breaking, allows for the stabilization of the Dark Matter (DM) candidates. We show that the electroweak precision observables, the electron and muon anomalous magnetic moments as well as the Charged Lepton Flavor Violating decays, μ → eγ, are consistent with the current experimental limits. In addition, we analyze the implications of the model for the 95 GeV diphoton excess recently reported by the CMS collaboration and demonstrate that such anomaly could be easily accommodated. Finally, we discuss qualitative aspects of DM in the considered model. © 2023, The Author(s).
Fast rotating blue stragglers prefer loose clusters
(Nature Research, 0023-12) Ferraro, Francesco R; Mucciarelli, Alessio; Lanzoni, Barbara; Pallanca, Cristina; Cadelano, Mario; Billi, Alex; Sills, Alison; Vesperini, Enrico; Dalessandro, Emanuele; Beccari, Giacomo; Monaco, Lorenzo; Mateo, Mario
Blue stragglers are anomalously luminous core hydrogen-burning stars formed through mass-transfer in binary/triple systems and stellar collisions. Their physical and evolutionary properties are largely unknown and unconstrained. Here we analyze 320 high-resolution spectra of blue stragglers collected in eight galactic globular clusters with different structural characteristics and show evidence that the fraction of fast rotating blue stragglers (with rotational velocities larger than 40 km/s) increases for decreasing central density of the host system. This trend suggests that fast spinning blue stragglers prefer low-density environments and promises to open an unexplored route towards understanding the evolutionary processes of these stars. Since large rotation rates are expected in the early stages of both formation channels, our results provide direct evidence for recent blue straggler formation activity in low-density environments and put strong constraints on the timescale of the collisional blue straggler slow-down processes. © 2023, The Author(s).
Designing an Optimal Kilonova Search Using DECam for Gravitational-wave Events
(Institute of Physics, 0024) Bom C.R.; Annis J; Garcia A.; Palmese A.; Sherman N.; Soares-Santos M.; Santana-Silva L; Morgan R.; Bechtol K; Davis T.; Diehl H.T.; Allam S.S.
We address the problem of optimally identifying all kilonovae detected via gravitational-wave emission in the upcoming LIGO/Virgo/KAGRA observing run, O4, which is expected to be sensitive to a factor of ∼7 more binary neutron star (BNS) alerts than previously. Electromagnetic follow-up of all but the brightest of these new events will require >1 m telescopes, for which limited time is available. We present an optimized observing strategy for the DECam during O4. We base our study on simulations of gravitational-wave events expected for O4 and wide-prior kilonova simulations. We derive the detectabilities of events for realistic observing conditions. We optimize our strategy for confirming a kilonova while minimizing telescope time. For a wide range of kilonova parameters, corresponding to a fainter kilonova compared to GW170817/AT 2017gfo, we find that, with this optimal strategy, the discovery probability for electromagnetic counterparts with the DECam is ∼80% at the nominal BNS gravitational-wave detection limit for O4 (190 Mpc), which corresponds to an ∼30% improvement compared to the strategy adopted during the previous observing run. For more distant events (∼330 Mpc), we reach an ∼60% probability of detection, a factor of ∼2 increase. For a brighter kilonova model dominated by the blue component that reproduces the observations of GW170817/AT 2017gfo, we find that we can reach ∼90% probability of detection out to 330 Mpc, representing an increase of ∼20%, while also reducing the total telescope time required to follow up events by ∼20%. © 2024. The Author(s). Published by the American Astronomical Society
Modified Heisenberg Commutation Relations and the Infinite-Square Well Potential: Some Simple Consequences
(Multidisciplinary Digital Publishing Institute (MDPI), 0024-10) González, Mauricio Contreras; Herrera, Roberto Ortiz; Gonzalez, José Mauricio
We explore some consequences of modifying the usual Heisenberg commutation relations of two simple systems: first, the one-dimensional quantum system given by the infinite square-well potential, and second, the case of a gas of N non-interacting particles in a box of volume V, which permit obtaining analytical solutions. We analyse two possible cases of modified Heisenberg commutation relations: one with a linear and non-linear dependence on the position and another with a linear and quadratic dependence on the momentum. We determine the eigenfunctions, probability densities, and energy eigenvalues for the one-dimensional square well for both deformation cases. For linear and non-linear x deformation dependence, the wave functions and energy levels change substantially when the weight factor associated with the modification term increases. Here, the energy levels are rescaled homogeneously. Instead, for linear and quadratic momentum p deformation dependence, the changes in the energy spectrum depend on the energy level. However, the probability densities are the same as those without any modification. For the non-interacting gas, the position deformation implies that the ideal gas state equation is modified, acquiring the form of a virial expansion in the volume, whereas the internal energy is unchanged. Instead, the ideal gas state equation remains unchanged at the lowest order in (Formula presented.) for the momentum modification case. However, the temperature modifies the internal energy at the lowest order in (Formula presented.). Thus, this study indicates that gravity could generate forces on particles by modifying the Heisenberg commutation relations. Therefore, gravitation could be the cause of the other three forces of nature. © 2024 by the authors.
The young exoplanetary system TOI-4562: Confirming the presence of a third body in the system
(LETTER TO THE EDITOR, 0024-10-09) Fermiano, V; Saito, RK; Ivanov, VD; Caceres, C; Almeida, LA; Aires, J; Beamin, JC; Minniti, D; Ferreira, T; Andrade, L; Borges, BW; de Almeida, L; Jablonski, F; Schlindwein, W
Young planetary systems represent an opportunity to investigate the early stages of (exo)planetary formation because the gravitational interactions have not yet significantly changed the initial configuration of the system. Aims. TOI-4562 b is a highly eccentric temperate Jupiter analogue orbiting a young F7V-type star of < 700 Myr in age with an orbital period of Porb similar to 225 days and an eccentricity of e = 0.76, and is one of the largest known exoplanets to have formed in situ. Methods. We observed a new transit of TOI-4562 b using the 0.6-m Zeiss telescope at the Pico dos Dias Observatory (OPD/LNA) in Minas Gerais, Brazil, and combine our data with Transiting Exoplanet Survey Satellite (TESS) and archive data, with the aim being to improve the ephemerides of this interesting system. Results. The O - C diagram for the new ephemeris is consistent with the presence of a giant planet in an outer orbit around TOI-4562. TOI-4562 c is a planet with a mass of M = 5.77 MJup, an orbital period of Porb = 3990 days, and a semi-major axis of a = 5.219 AU. Conclusions. We report the discovery of TOI-4562 c, the exoplanet with the longest orbital period discovered to date via the transit timing variation (TTV) method. The TOI-4562 system is in the process of violent evolution with intense dynamical changes - judging by its young age and high eccentricity - and is therefore a prime target for studies of formation and evolution of planetary systems.
The fast rise of the unusual type IIL/IIb SN 2018ivc
(EDP Sciences, 0024-12) Reguitti A; Dastidar R.; Pignata G; Maeda K.; Moriya T.J.; Kuncarayakti H.; Rodríguez Ó; Bersten M.; Anderson J.P.; Charalampopoulos P.; Fraser M; Gromadzki M.
We present an analysis of the photometric and spectroscopic dataset of the type II supernova (SN) 2018ivc in the nearby (10 Mpc) galaxy Messier 77. Thanks to our high-cadence data, we observed the SN rising very rapidly by nearly three magnitudes in five hours (or 18 mag d- 1). The r-band light curve presents four distinct phases: the maximum light, which was reached in just one day, followed by a first, rapid linear decline and a short-duration plateau. Finally, the long, slower linear decline lasted for one year. Thanks to the ensuing radio re-brightening, we were able to detect SN 2018ivc four years after the explosion. The early spectra show a blue, nearly featureless continuum, but the spectra go on to evolve rapidly; after about ten days, a prominent Hα line starts to emerge, characterised by a peculiar profile. However, the spectra are heavily contaminated by emission lines from the host galaxy. The He I lines, namely λλ5876,7065, are also strong. In addition, strong absorption from the Na I doublet is evident and indicative of a non-negligible internal reddening. From its equivalent width, we derived a lower limit on the host reddening of AV ≲ 1.5 mag. From the Balmer decrement and a match of the B- V colour curve of SN 2018ivc to that of the comparison objects, we obtained a host reddening of AV ≲ 3.0 mag. The spectra are similar to those of SNe II, but with strong He lines. Given the peculiar light curve and spectral features, we suggest SN 2018ivc could be a transitional object between the type IIL and type IIb SNe classes. In addition, we found signs of an interaction with the circum-stellar medium (CSM) in the light curve, also making SN 2018ivc an interacting event. Finally, we modelled the early multi-band light curves and photospheric velocity of SN 2018ivc to estimate the physical parameters of the explosion and CSM. © The Authors 2024.
Decoding the formation of hammerhead ion populations observed by Parker Solar Probe
(EDP Sciences, 0024-12) Shaaban, Shaaban M; Lazar M; López R.A.; Yoon P.H.; Poedts S
Context. In situ observations by the Parker Solar Probe (PSP) have revealed new properties of the proton velocity distributions (VDs), including hammerhead features that suggest a non-isotropic broadening of the beams. Aims. The present work proposes a very plausible explanation for the formation of hammerhead proton populations through the action of a proton firehose-like instability triggered by the proton beam. Methods. We investigated a self-generated firehose-like instability driven by the relative drift of ion populations using a simplified moment-based quasi-linear (QL) theory. While simpler and faster than advanced numerical simulations, this toy model provided rapid insights and concisely highlighted the role of plasma micro-instabilities in relaxing the observed anisotropies of particle VDs in the solar wind and space plasmas. Results. The QL theory proposed here shows that the resulting transverse waves are right-hand polarized and have two consequences on the protons: (i) They reduce the relative drift between the beam and the core, but above all, (ii) they induce a strong perpendicular temperature anisotropy specific to the observed hammerhead ion beam. Moreover, the long-run QL results suggest that these hammerhead distributions are rather transitory states that are still subject to relaxation mechanisms, in which instabilities such as the one discussed here are very likely involved. This foundational work motivates future detailed studies using advanced methods. © The Authors 2024.
The Milky Way accretion history compared to cosmological simulations: From bulge formation to dwarf galaxy infall
(EDP Sciences, 0024-12) Hammer F; Jiao Y.J.; Mamon G.A; Yang Y.B; Akib I.; Amram P.; Wang H.F.; Wang J.L; Chemin L.
Galactic halos are known to grow hierarchically, inside out. This implies a correlation between the infall lookback time of satellites and their binding energy. Cosmological simulations predict a linear relation between the infall lookback time and the logarithm of the binding energy, with a small scatter. Gaia measurements of the bulk proper motions of globular clusters and dwarf satellites of the Milky Way are sufficiently accurate to establish the kinetic energies of these systems. Assuming the gravitational potential of the Milky Way, we can deduce the binding energies of the dwarf satellites and those of the galaxies that were previously accreted by the Milky Way. This can be compared to cosmological simulations for the first time. The relation of the infall lookback time versus binding energy we found in a cosmological simulation matches that for the early accretion events when the simulated total Milky Way mass within 21 kpc was rescaled to 2 1011 M. This agrees well with previous estimates from globular cluster kinematics and from the rotation curve. However, the vast majority of the dwarf galaxies are clear outliers to this rescaled relation, unless they are very recent infallers. In other words, the very low binding energies of most dwarf galaxies compared to Sgr and previous accreted galaxies suggests that most of them were accreted much later than 8 or even 5 Gyr ago. We also found that the subhalo systems in some cosmological simulations are too dynamically hot when they are compared to identified Milky Way substructures. This leads to an overestimated impact of satellites on the Galaxy rotation curve. © 2024 EDP Sciences. All rights reserved.
Documentary Analysis of Hypericum perforatum (St. John’s Wort) and Its Effect on Depressive Disorders
(Multidisciplinary Digital Publishing Institute (MDPI), 0024-12) Otero, María Carolina; Ceric, Francisco; Miranda-Rojas, Sebastián; Carreño, Carolina; Atala, Cristian; Ramírez-Barrantes, Ricardo; Gordillo-Fuenzalida, Felipe
Hypericum perforatum, also known as St. John’s Wort, pericon, or yellow grass, is known for its antidepressant potential. It could represent a natural alternative to current pharmacological antidepressant treatments, which have a high incidence of side effects in patients and therefore lead to early dropouts. Through a bibliographic revision of clinical trials and information collected from scientific articles during the first period of 2020, we aimed to evaluate whether its administration could be beneficial in the treatment of mild-to-moderate depression, with fewer side effects compared to synthetic drugs. Among the main components, hypericin and hyperforin have been related to the observed antidepressant activity; therefore, their possible mechanism of action was reviewed and highlighted. Furthermore, patients receiving Hypericum extracts were less likely to withdraw from studies because of adverse effects compared to those receiving older standard antidepressants. This review aims to provide suggestions for an alternative treatment of mild-to-moderate depression disorder under the supervision of a medical doctor, since, although it appears to be a potentially efficient treatment with a low presence of adverse effects in comparison to synthetic antidepressants, it might also interact with other medications and lead to therapeutic failures if misused for self-medication. © 2024 by the authors.
Polynomial Affine Model of Gravity: After 10 Years
(Multidisciplinary Digital Publishing Institute (MDPI), 0025) Castillo-Felisola, Oscar; Grez, Bastian; Morocho-López, Manuel; Skirzewski, Aureliano; Vaca-Santana, Jefferson; Zambra-Gómez, Nicolas
The polynomial affine model of gravity was proposed as an alternative to metric and metric-affine gravitational models. What, in the beginning, was thought to be a source of unpredictability—the presence of many terms in the action—turned out to be a milestone since it contains all possible combinations of the fields compatible with the covariance under diffeomorphisms. Here, we present a review of the advances in the analysis of the model after 10 years of its proposal and sketch the guidelines for our future perspectives. © 2025 by the authors.
Development of molecularly imprinted polymers for the detection of human chorionic gonadotropin
(Nature Research, 0025) Zubrytė, Radvilė; Mavliutova, Liliia; García, Yadiris; Sullivan, Mark V.; Turner, Nicholas W.; Patitucci, Francesco; Polania, Laura C.; Jiménez, Verónica A; Porter, Robert; Mattsson, Alice; Sellergren, Börje
Diagnostic pregnancy tests are the most widely used immunoassays for home-based use. These tests employ the well-established lateral flow assay (LFA) technique, reminiscent of affinity chromatography relying on the dual action of two orthogonal anti-hCG antibodies. Immunoassays suffer from several drawbacks, including challenges in antibody manufacturing, suboptimal accuracy, and sensitivity to adverse storing conditions. Additionally, LFAs are typically designed for single use, as the LFA technique is non-reusable. An alternative to overcome these drawbacks is to leverage molecularly imprinted polymer (MIP) technology to generate polymer-based hCG-receptors and, subsequently, non-bioreceptor-based tests. Here, we report the development of MIP nanogels for hCG detection, exploiting epitopes and magnetic templates for high-yielding dispersed phase imprinting. The resulting nanogels were designed for orthogonal targeting of two immunogenic epitopes (SV and PQ) and were thoroughly characterized with respect to physical properties, binding affinity, specificity, and sensitivity. Molecular dynamics simulations indicated a pronounced conformational overlap between the templates and the epitopes in the native protein, supporting their suitability for templating cavities for hCG recognition. Quartz crystal microbalance (QCM)-based binding tests and kinetic interaction analysis by surface plasmon resonance (SPR) revealed nanomolar dissociation constants for the MIP nanogels and their corresponding template peptides and low uptake of lutenizing hormone (LH), structurally resembling to hCG. Receptor reusability was demonstrated in the multicycle SPR sensing mode using a low pH regeneration buffer. The results suggest the feasibility of using imprinted nanogels as a class of cost-effective, stable alternatives to natural antibodies for hCG detection. We foresee applications of these binders with respect to reusable pregnancy tests and other hCG-related disease diagnostics. © The Author(s) 2025.
CHANCES, the Chilean Cluster Galaxy Evolution Survey: Selection and initial characterisation of clusters and superclusters
(EDP Sciences, 0025) Sifón, Cristóbal; Finoguenov, Alexis; Haines, Christopher P; Jaffé, Yara; Amrutha B.M.; Demarco, Ricardo; Lima E.V.R; Lima-Dias, Ciria; Méndez-Hernández, Hugo; Merluzzi, Paola; Monachesi, Antonela; Teixeira, Gabriel S. M.
CHANCES, the CHileAN Cluster galaxy Evolution Survey, will study the evolution of galaxies in and around 100 massive galaxy clusters from the local Universe out to z = 0.45, and two superclusters at z ∼ 0.05 that contain roughly 25 Abell clusters each. CHANCES will use the new 4MOST Spectroscopic Survey Facility on the VISTA 4m telescope to obtain spectra for ∼500 000 galaxies with magnitudes rAB < 20.4, providing comprehensive spectroscopic coverage of each cluster out to 5r200. Its wide and deep scope will trace massive and dwarf galaxies from the surrounding filaments and groups to the cores of galaxy clusters. This will enable the study of galaxy preprocessing and of the role of the evolving environment on galaxy evolution. In this paper, we present and characterise the sample of clusters and superclusters to be targeted by CHANCES. We used literature catalogues based on X-ray emission and the Sunyaeva-Zel'dovich effect to define the cluster sample in a homogeneous way, with attention to cluster mass and redshift, as well as the availability of ancillary data. We calibrated literature mass estimates from various surveys against each other and provide an initial mass estimate for each cluster, which we used to define the radial extent of the 4MOST coverage. We also present an initial assessment of the structure surrounding these clusters based on the redMaPPer red-sequence algorithm as a preview of some of the science CHANCES will enable. © The Authors 2025
Regioselective cyclocondensations with thiobarbituric acid: spirocyclic and azocine products, X-ray characterization, and antioxidant evaluation
(Royal Society of Chemistry, 0025) Polo-Cuadrado, Efraín; Acosta-Quiroga, Karen; Rojas-Peña, Cristian; Rodriguez-Nuñez, Yeray A; Blanco-Acuña, Edgard Fabián; Lopez, Jhon J; Brito, Iván; Cisterna, Jonathan; Alderete, Joel B; Gutiérrez, Margarita
Multicomponent cyclocondensations of 5-amino-3-methyl-1-phenyl-1H-pyrazole (AMPZ), thiobarbituric acid, and p-formaldehyde under conventional thermal heating or ultrasonic irradiation were studied. Treatment of the reaction mixture in ethanol in an ultrasonic bath for 3 h produced azocine compound 4b, while the same mixture in ethanol under reflux conditions for 15 h produced spiro compound 4a. This work encompasses intricate experimental details, X-ray diffraction measurements, and multifaceted computational analyses employing methods such as the density functional theory and Hirshfeld surface analysis. Crystallographic investigations revealed the molecular structure of the compound and clarified its interactions involving hydrogen bonds and weak intermolecular forces. This article describes the synthesis and characterization of a novel spirocyclic compound. The study also evaluated the antioxidant potential in vitro using the DPPH and ABTS methods. The results showed that these compounds showed the best free radical scavenging ability, even in very small amounts, and that even at very low concentrations, these compounds showed excellent radical scavenging potential. Surprisingly, these compounds exhibited strong (ABTS+) radical scavenging activities, mainly attributed to the HAT mechanism, indicating their potential as therapeutic agents. Facile multipurpose, three-component selective procedures for new spiroheterocycles have been proposed, presenting intriguing perspectives in the field of medicine, particularly in the field of antioxidants. The geometric values of the computationally optimized structure were calculated using the density functional theory in LC-BLYP/6-31(d), aligned with the X-ray diffraction data, reinforcing the precision of our findings. © 2025 The Royal Society of Chemistry.
Looking at the Distant Universe with the MeerKAT Array: The H i Mass Function in the Local Universe
(Institute of Physics, 0025) Kazemi-Moridani, Amir; Baker, Andrew J; Verheijen, Marc; Gawiser, Eric; Blyth, Sarah-Louise; Obreschkow, Danail; Chemin, Laurent f; Collier, Jordan D.; Cook, Kyle W.; Delhaize, Jacinta; Elson, Ed; Frank, Bradley S.
We present measurements of the neutral atomic hydrogen (H i) mass function (HiMF) and cosmic H i density (ΩH I) at 0 ≤ z ≤ 0.088 from the Looking at the Distant Universe with MeerKAT Array (LADUMA) survey. Using LADUMA Data Release 1 (DR1), we analyze the HiMF via a new “recovery matrix” method that we benchmark against a more traditional modified maximum likelihood (MML) method. Our analysis, which implements a forward modeling approach, corrects for survey incompleteness and uses extensive synthetic source injections to ensure robust estimates of the HiMF parameters and their associated uncertainties. This new method tracks the recovery of sources in mass bins different from those in which they were injected and incorporates a Poisson likelihood in the forward modeling process, allowing it to correctly handle uncertainties in bins with few or no detections. The application of our analysis to a high-purity subsample of the LADUMA DR1 spectral line catalog in turn mitigates any possible biases that could result from the inconsistent treatment of synthetic and real sources. For the surveyed redshift range, the recovered Schechter function normalization, low-mass slope, and “knee” mass are ϕ * = 3.5 6 − 1.92 + 0.97 × 1 0 − 3 Mpc−3 dex−1, α = − 1.1 8 − 0.19 + 0.08 , and log ( M * / M ⊙ ) = 10.0 1 − 0.12 + 0.31 , respectively, which together imply a comoving cosmic H i density of Ω H I = 3.0 9 − 0.47 + 0.65 × 1 0 − 4 . Our results show consistency between recovery matrix and MML methods and with previous low-redshift studies, giving confidence that the cosmic volume probed by LADUMA, even at low redshifts, is not an outlier in terms of its H i content. © 2025. The Author(s). Published by the American Astronomical Society.
The Gaia Parallax Discrepancy for the Cluster Pismis 19 and Separating δ Scutis from Cepheids
(Institute of Physics, 0025) Majaess, Daniel; Bonatto, Charles J.; Turner, David G; Saito, Roberto K; Minniti, Dante; Moni Bidin, Christian; González-Díaz, Danilo; Alonso-Garcia, Javier; Bono, Giuseppe; Braga, Vittorio F.; Navarro, Maria G; Carraro, Giovanni
Pre-Gaia distances for the open cluster Pismis 19 disagree with Gaia parallaxes. A Two Micron All Sky Survey (2MASS) JKs red clump distance was therefore established for Pismis 19 (2.90 ± 0.15 kpc), which reaffirms that zero-point corrections for Gaia are required. OGLE GD-CEP-1864 is confirmed as a member of Pismis 19 on the basis of DR3 proper motions and its 2MASS+Vista Variables in the Vía Láctea color-magnitude position near the tip of the turnoff. That 0.3 day variable star is likely a δ Scuti rather than a classical Cepheid. The case revealed a pertinent criterion to segregate those two populations in tandem with the break in the Wesenheit Leavitt Law (≃0.5 day). Just shortward of that period discontinuity are δ Scutis, whereas beyond the break lie first overtone classical Cepheids mostly observed beyond the first crossing of the instability strip. © 2025. The Author(s). Published by the American Astronomical Society.
Development of molecularly imprinted polymers for the detection of human chorionic gonadotropin
(Nature Research, 0025) Zubrytė, Radvilė; Mavliutova, Liliia; García, Yadiris; Sullivan, Mark V.; Turner, Nicholas W.; Patitucci, Francesco; Polania, Laura C. d; Jiménez, Verónica A.; Porter, Robert; Mattsson, Alice; Sellergren, Börje b
Diagnostic pregnancy tests are the most widely used immunoassays for home-based use. These tests employ the well-established lateral flow assay (LFA) technique, reminiscent of affinity chromatography relying on the dual action of two orthogonal anti-hCG antibodies. Immunoassays suffer from several drawbacks, including challenges in antibody manufacturing, suboptimal accuracy, and sensitivity to adverse storing conditions. Additionally, LFAs are typically designed for single use, as the LFA technique is non-reusable. An alternative to overcome these drawbacks is to leverage molecularly imprinted polymer (MIP) technology to generate polymer-based hCG-receptors and, subsequently, non-bioreceptor-based tests. Here, we report the development of MIP nanogels for hCG detection, exploiting epitopes and magnetic templates for high-yielding dispersed phase imprinting. The resulting nanogels were designed for orthogonal targeting of two immunogenic epitopes (SV and PQ) and were thoroughly characterized with respect to physical properties, binding affinity, specificity, and sensitivity. Molecular dynamics simulations indicated a pronounced conformational overlap between the templates and the epitopes in the native protein, supporting their suitability for templating cavities for hCG recognition. Quartz crystal microbalance (QCM)-based binding tests and kinetic interaction analysis by surface plasmon resonance (SPR) revealed nanomolar dissociation constants for the MIP nanogels and their corresponding template peptides and low uptake of lutenizing hormone (LH), structurally resembling to hCG. Receptor reusability was demonstrated in the multicycle SPR sensing mode using a low pH regeneration buffer. The results suggest the feasibility of using imprinted nanogels as a class of cost-effective, stable alternatives to natural antibodies for hCG detection. We foresee applications of these binders with respect to reusable pregnancy tests and other hCG-related disease diagnostics. © The Author(s) 2025.
Dynamic spectra of solar radio emissions from weak-turbulence simulation
(EDP Sciences, 0025) Lazar M.; Ziebell L.F.; Yoon P.H; López R.A.; Poedts S.
Context. In recent decades, serious efforts have been made in the analytical and numerical modeling of solar radio bursts generated by the electron beam interacting with the background plasma, including the dynamic spectra with decreasing frequency over time/space. These are type II and type III radio bursts, with the fundamental components at the local plasma frequency (ωp = 2π fp) and the harmonics (nωp = 2πnfp). Synthetic spectra built for a number of radio events were able to reproduce the decreasing frequency profiles reasonably well, despite the limitations of the approximate analytical theory. Aims. We propose new modeling of dynamic radio emission spectra using weak-turbulence (WT) theory. This novel approach also aims at a self-consistent and quantitative evaluation of radio emissions, based on first-principles modeling of electron beam plasma instabilities and nonlinear wave interaction. Methods. We performed the WT simulation, which has the ability to quantitatively describe the standard plasma emission involving the nonlinear interaction of Langmuir (L), ion-sound (S), and transverse electromagnetic (T) waves. The composite dynamic spectra are constructed for type II- and type III-like events, against the background electron density model that behaves as an inverse square of the distance from the solar source. Results. The new dynamic spectra are obtained distinctly, with a rapid frequency shift for type III emissions (generated by fast electron beams from coronal sources), as well as a less steep frequency drop for type II spectra (whose sources move away from the Sun along with interplanetary shocks). Upon making a qualitative comparison with typical solar radio emission events, we find that our first-principle-based synthetic dynamic spectra are in good agreement. Conclusions. The findings of the present study demonstrate that the theoretical approach taken in this paper can be further applied to obtain (i) quantitatively relevant predictions and replications of the observed dynamic spectra of radio bursts, and (ii) more realistic large-scale models of the solar radio source, for example the type II and type III source models computed from the large-scale magnetohydrodynamics (MHD) simulations or even from direct spacecraft observations. © The Authors 2025.
Circumstellar emission of Cepheids across the instability strip: Mid-infrared observations with VLTI/MATISSE
(EDP Sciences, 0025) Hocdé V.; Matter A.; Nardetto N.; Gallenne A.; Kervella P.; Mérand A; Pietrzyń Ski G; Gieren W.; Leftley J; Robbe-Dubois S; Lopez B.; Bailleul M.C.; Bras G; Smolec R; Wielgórski P.; Hajdu G.; Afanasiev A
Context. The circumstellar envelopes (CSE) of Cepheids are still only poorly characterized despite their potential impact on the distance determination via both the period-luminosity relation and the parallax-of-pulsation method. Aims. This paper aims to investigate Galactic Cepheids across the instability strip in the mid-infrared with MATISSE/VLTI in order to constrain the geometry and physical nature (gas and/or dust) of their CSEs. Methods. We secured observations of eight Galactic Cepheids with short- and up to long-period pulsations with MATISSE/VLTI in the L, M, and N bands. For each star, we calibrated the flux measurements to potentially detect the spectral dust signature in the spectral energy distribution (SED). We then analyzed the closure phase and the visibilities in L, M, and N bands. The parallax-of-pulsation code SPIPS was used in order to derive the infrared excess and the expected angular stellar diameter at the date of the MATISSE observations. We also computed test cases of a radiative transfer model of dusty envelopes with DUSTY to compare them with the visibilities in the N band. Results. The SED analysis in the mid-IR confirmed the absence of a spectral dust signature for the entire star sample. For each star, we observed closure phases in the L, M, and N bands that are consistent with a centro-symmetric geometry for the different targets. Finally, the visibilities in the L, M, and N bands agree with the expected angular stellar diameter. Although we did not resolve any circumstellar emission, the observations are compatible with the presence of compact CSEs within the uncertainties. We provide 2 σ upper limits on the CSE flux contribution based on model residuals for several CSE radii, which exclude models that are simultaneously large and bright (RCSE ≈ 10 R∗ and fCSE ≈ 10%) for all the stars of the sample. Last, the visibilities in the N band rule out CSE models with optical depth τV ≳ 0.001 for different types of dust. Conclusions. The MATISSE observations of eight Cepheids with different pulsation periods (from 7 to 38 days) and evolution stages provide a comprehensive picture of Cepheids from mid-infrared interferometry for the first time. We present additional evidence that circumstellar dust emission is negligible or absent around Cepheids for a wide range of stellar parameters in the instability strip. Further interferometric observations in the visible and near-infrared are required to separate the star and CSE, which is crucial for constraining the CSE contribution and its possible gaseous nature. © The Authors 2025.
The Gaia Parallax Discrepancy for the Cluster Pismis 19 and Separating δ Scutis from Cepheids
(Institute of Physics, 0025) Majaess, Daniel; Bonatto, Charles J.; Turner, David G; Saito, Roberto K; Minniti, Dante; Moni Bidin, Christian; González-Díaz, Danilo; Alonso-Garcia, Javier; Bono, Giuseppe; Braga, Vittorio F.; Navarro, Maria G.; Carraro, Giovanni
Pre-Gaia distances for the open cluster Pismis 19 disagree with Gaia parallaxes. A Two Micron All Sky Survey (2MASS) JKs red clump distance was therefore established for Pismis 19 (2.90 ± 0.15 kpc), which reaffirms that zero-point corrections for Gaia are required. OGLE GD-CEP-1864 is confirmed as a member of Pismis 19 on the basis of DR3 proper motions and its 2MASS+Vista Variables in the Vía Láctea color-magnitude position near the tip of the turnoff. That 0.3 day variable star is likely a δ Scuti rather than a classical Cepheid. The case revealed a pertinent criterion to segregate those two populations in tandem with the break in the Wesenheit Leavitt Law (≃0.5 day). Just shortward of that period discontinuity are δ Scutis, whereas beyond the break lie first overtone classical Cepheids mostly observed beyond the first crossing of the instability strip. © 2025. The Author(s). Published by the American Astronomical Society.
Long-lived particle phenomenology in one-loop neutrino mass models with dark matter
(Springer Science and Business Media Deutschland GmbH, 0025) Arbeláez, Carolina; Cottin, Giovanna; Helo, Juan Carlos; Hirsch, Martin; de Melo, Téssio B.
Neutrino masses and dark matter (DM) might have a common origin. The scotogenic model can be considered the proto-type model realizing this idea, but many other variants exist. In this paper we explore the phenomemology of a particular DM neutrino mass model, containing a triplet scalar. We calculate the relic density and check for constraints from direct detection experiments. The parameter space of the model, allowed by these constraints, contains typically a long-lived or quasi-stable doubly charged scalar, that can be searched for at the LHC. We reinterpret existing searches to derive limits on the masses of the scalars of the model and estimate future sensitivities in the high-luminosity phase of the LHC. The searches we discuss can serve to constrain also many other 1-loop neutrino mass models. © The Author(s) 2025.

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