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Navigating the Ethics of Internet Measurement: Researchers' Perspectives from a Case Study in the EU
No full textInternet measurement research is essential for understanding, improving, and securing Internet infrastructure. However, its methods often involve large-scale data collection and user observation, raising complex ethical questions. While recent research has identified ethical challenges in Internet measurement research and laid out best practices, little is known about how researchers actually make ethical decisions in their research practice. To understand how these practices take shape day-to-day from the perspective of Internet measurement researchers, we interviewed 16 researchers from an Internet measurement research group in the EU. Through thematic analysis, we find that researchers deal with five main ethical challenges: privacy and consent issues, the possibility of unintended harm, balancing transparency with security and accountability, uncertain ethical boundaries, and hurdles in the ethics review process. Researchers address these by lab testing, rate limiting, setting up clear communication channels, and relying heavily on mentors and colleagues for guidance. Researchers express that ethical requirements vary across institutions, jurisdictions and conferences, and ethics review boards often lack the technical knowledge to evaluate Internet measurement research. We also highlight the invisible labor of Internet measurement researchers and describe their ethics practices as craft knowledge, both of which are crucial in upholding responsible research practices in the Internet measurement community
Randomized, double-blind, sham-controlled pilot trial of theta-band transcranial alternating current stimulation during cognitive training in mild Alzheimer's disease
No full textCognitive deficits are a hallmark of Alzheimer’s disease (AD), and effective treatments remain elusive. Transcranial alternating current stimulation (tACS), a non-invasive technique, has shown potential in improving cognitive function across various populations, but further research is needed to investigate its efficacy in AD. In a randomized, double-blind, sham-controlled pilot trial, 36 mild AD patients received active or sham theta-tACS (8 Hz, 1.6 mA, 20-min daily) during n-back task for two weeks, followed by a 10-week follow-up. Cognitive assessments and resting-state EEG were analyzed at baseline, after-treatment, and follow-up. The results showed that the active group demonstrated significant cognitive improvements after treatment (MMSE: t (15) =-3.273, p = 0.005, Cohen’s d = 0.82), particularly in short-term memory (MMSE-recall: Z = -2.11, p = 0.035, r = 0.53), with maintained benefits after 10 weeks. In contrast, the sham group exhibited long-term cognitive decline (MMSE: t (4) = 3.586, p = 0.023, Cohen’s d = -1.60). EEG analysis revealed reduced gamma power (t (23) = 2.689, p = 0.013, Cohen’s d = 1.077) and theta connectivity in active group, particularly in the frontotemporal regions (F4/F7: t (23) = 2.467, p = 0.021, Cohen’s d = 0.988; F4/T3: t (23) = 2.465, p = 0.022, Cohen’s d = 0.987), which was correlated with cognitive improvements (R = –0.57, p = 0.043). In conclusion, tACS combining cognitive training may offer cognitive benefits in mild AD by modulating neural activity, though further studies are needed to clarify its mechanisms
The AURORA Survey: Ionizing Photon Production Efficiency with Minimal Nebular Dust Attenuation Systematics
No full textWe present ionizing photon production efficiencies (xi ion) for 63 z = 1.5-6.9 star-forming galaxies using precise nebular dust attenuation corrections from the JWST Assembly of Ultradeep Rest-optical Observations Revealing Astrophysics (AURORA) survey. A subset of objects within AURORA have individually determined nebular dust attenuation curves, which vary significantly in shape and normalization, resulting in reduced systematic uncertainty when constraining the total attenuation of H alpha luminosity, and thus the intrinsic ionizing output within our sample. We find evidence for positive correlations between xi ion and redshift, equivalent width of [O iii] lambda 5007, and O32 = [O iii] lambda 5007/[O ii] lambda lambda 3726, 3729, and negative correlations between xi ion and stellar attenuation, UV luminosity (LUV), stellar mass, and direct-method metallicity. We test alternate dust prescriptions within this sample, and find that the total attenuation is lower when using the commonly assumed Galactic extinction curve or when assuming that stellar attenuation is equal to nebular attenuation. We also find that assuming either of these alternate dust prescriptions can change the slope of the relationships between xi ion and galaxy property, notably inducing a flat trend between xi ion and LUV within AURORA. While the novel nebular dust curves derived from AURORA spectroscopy reveal obscured ionizing photon production within star-forming galaxies at these redshifts, a more complete understanding of stellar attenuation is required to fully reduce the dust systematics on xi ion for inclusion in reionization models
Regulating Cu Atom Dispersity on Nitrogen-Doped Carbon for Boosting Electrocatalytic Nitrate Reduction in Strongly Acidic Media
No full textProducing ammonia (NH3) by nitrate reduction reaction (NO3RR) under acidic conditions has considerable economic value, but there is still a lack of stable and efficient catalysts, due to the complex NO3RR process, strongly competing hydrogen evolution reaction (HER), and highly corrosive environment. Herein, a series of Cu-based catalysts with different Cu atom dispersity on N-doped carbon are developed for acidic NO3RR, where the Cu element can be controlled from single atoms to nanoparticles by tuning the pyrolysis temperature. The catalyst that contains both single atoms and nanoparticles exhibits the optimal electrocatalytic performance, achieving a maximal NH3 Faraday efficiency of 98.6 % and a high NH3 yield of 11.8 mg h-1 cm-2 at -0.3 V (vs. RHE) under a strongly acidic environment. Theoretical calculations combined with in-situ characterization techniques reveal that the coexistence of Cu single atoms and nanoparticles promotes the two-step relay catalysis, and that the interaction between nanoparticles and surrounding single atoms can optimize the intermediate adsorption, thus reducing the reaction energy barrier of the NO3RR process and suppressing competing HER. This work highlights the effects of synergy between single atoms and nanoparticles on boosting tandem catalysis and provides a reasonable reference for developing acidic NO3RR electrocatalysts
Sound lateralization ability is affected by saccade direction but not eye movement-related eardrum oscillations (EMREOs) (Version posted online February 05, 2026)
No full textSymmetry, microscopy and spectroscopy signatures of altermagnetism
No full textThe recent discovery of altermagnetism was in part motivated by the research of compensated magnets towards highly scalable spintronic technologies. Simultaneously, altermagnetism shares the anisotropic higher-partial-wave nature of ordering with unconventional superfluid phases, which have been at the forefront of research for the past several decades. These examples illustrate the interest in altermagnetism from a broad range of science and technology perspectives. Here we review the symmetry, microscopy and spectroscopy signatures of altermagnetism. We describe the spontaneously broken and retained symmetries that delineate altermagnetism as a distinct phase of matter with d-, g- or i-wave compensated collinear spin ordering. In materials ranging from weakly interacting metals to strongly correlated insulators, the microscopic crystal-structure realizations of the altermagnetic symmetries feature a characteristic ferroic order of anisotropic higher-partial-wave components of atomic-scale spin densities. These symmetry and microscopy signatures of altermagnetism are directly reflected in spin-dependent electronic spectra and responses. We review salient band-structure features originating from the altermagnetic ordering, and from its interplay with spin–orbit coupling and topological phenomena. Throughout, we compare altermagnetism with traditional ferromagnetism and Néel antiferromagnetism, and with magnetic phases with symmetry-protected compensated non-collinear spin orders. We accompany the theoretical discussions with references to relevant experiments. © Springer Nature Limited 2026
The early Universe with JWST and ALMA
No full textThe Atacama Large Millimeter/submillimeter Array and the James Webb Space Telescope are transforming our understanding of galaxy formation and evolution in the early Universe. By combining their capabilities, these observatories provide unprecedented insights into the gas, dust and stars of high-redshift galaxies at spatially resolved scales, unveiling the complexities of their interstellar medium, kinematics, morphology, active galactic nuclei and star-formation activity. This review summarizes recent breakthroughs in the study of galaxies during the first billion years of cosmic history, highlighting key discoveries, open questions and current limitations. We discuss how observations, theoretical models and simulations are shaping our understanding of early galaxy evolution and identify promising directions for future research. While substantial progress can be achieved through optimized use of existing facilities and collaborative efforts, further advances will require enhanced angular resolution and sensitivity, motivating upgrades to current instruments and the development of next-generation observatories
High-Resolution Infrared Spectroscopy and ASAP Analysis of Cyclopentadiene: The Vibrational Modes below 860 cm-1 and the ν21 Mode at 961 cm-1
No full textThe spectroscopic fingerprints of vibrationally excited states of astronomical molecules are interesting for multiple reasons. They are excellent temperature probes of the corresponding astronomical regions and are thought to be the origin of many unknown lines in astronomical survey spectra. Rovibrational spectra provide accurate vibrational energies and can guide subsequent pure rotational studies. The Automated Spectral Assignment Procedure (ASAP) greatly simplifies the rovibrational analysis when the rotational spectrum of either the upper or lower vibrational state is known with a high degree of accuracy (e.g., from a rotational analysis). Here, we present a new implementation of ASAP for the analysis of cyclopentadiene, a cyclic pure hydrocarbon that has already been detected astronomically toward the cold core of the Taurus Molecular Cloud. Using the synchrotron radiation extracted by the AILES beamline of the SOLEIL facility, we recorded mid- and far-infrared high-resolution spectra of cyclopentadiene. We analyzed the rovibrational spectrum of the nu 21 fundamental (961 cm-1) with ASAP and used ASAP2 to determine the vibrational energies of the eight vibrational modes below 860 cm-1. ASAP2 is an extension of ASAP for rovibrational bands where the rotational structures of the lower and upper states are known with high accuracy, leaving only the vibrational band center to be determined. The presented rovibrational fingerprints agree with the results from pure rotational spectroscopy, demonstrating the efficiency and reliability of our new ASAP implementation
Discovery of an X-Ray Luminous Radio-loud Quasar at z=3.4: A Possible Transitional Super-Eddington Phase
No full textWe report the multiwavelength properties of eROSITA Final Equatorial Depth Survey (eFEDS) J084222.9+001000 (hereafter ID830), a quasar at z = 3.4351, identified as the most X-ray luminous radio-loud quasar in the eFEDS field. ID830 shows a rest-frame 0.5-2 keV luminosity of log (L0.5-2kev/erg S-1)=46.20 +/- 0.12, with a steep X-ray photon index (Gamma = 2.43 +/- 0.21), and a significant radio counterpart detected with the Very Large Array FIRST 1.4 GHz and Very Large Array Sky Survey 3 GHz bands. The rest-frame UV to optical spectra from Sloan Digital Sky Survey and Subaru/MOIRCS J band show a dust-reddened quasar feature with A(V) = 0.39 +/- 0.08 mag, and the expected bolometric active galactic nuclei luminosity from the dust-extinction-corrected UV luminosity reaches L-bol,L-3000 & Aring; = (7.62 +/- 0.31) x 10(46) erg s(-1). We estimate a black hole mass of M-BH = (4.40 +/- 0.72) x 10(8) M-circle dot based on the Mg II lambda 2800 emission-line width, and Eddington ratios from the dust-extinction-corrected UV continuum luminosity and X-ray luminosity that reach lambda(Edd,UV) = 1.44 +/- 0.24 and lambda(Edd,X) = 12.8 +/- 3.9, respectively, both indicating super-Eddington accretion. ID830 shows a high ratio of UV to X-ray luminosities, alpha(OX) = -1.20 +/- 0.07 (or alpha(OX) = -1.42 +/- 0.07 after correcting for jet-linked X-ray excess), higher than quasars and little red dots in the super-Eddington phase with similar UV luminosities, with alpha(OX) < -1.8. Such a high alpha(OX) suggests the coexistence of a prominent radio jet and X-ray corona in this high-Eddington-accretion phase. We propose that ID830 may be in a transitional phase after an accretion burst, evolving from a super-Eddington to a sub-Eddington state, which could naturally describe the high alpha(OX)
Euclid: An emulator for baryonic effects on the matter bispectrum
No full textThe Euclid mission and other next-generation large-scale structure surveys will enable high-precision measurements of the cosmic matter distribution. Understanding the impact of baryonic processes such as star formation and active galactic nuclei (AGN) feedback on matter clustering is crucial to ensure precise and unbiased cosmological inference. Most theoretical models of baryonic effects to date focus on two-point statistics, neglecting higher-order contributions. This work develops a fast and accurate emulator for baryonic effects on the matter bispectrum, a key non-Gaussian statistic in the nonlinear regime. We employ high-resolution N-body simulations from the BACCO suite and apply a combination of cutting-edge techniques such as cosmology scaling and baryonification to efficiently span a large cosmological and astrophysical parameter space. A deep neural network is trained to emulate baryonic effects on the matter bispectrum measured in simulations, capturing modifications across various scales and redshifts relevant to Euclid. We validate the emulator accuracy and robustness using an analysis of Euclid mock data, employing predictions from the state-of-the-art FLAMINGO hydrodynamical simulations. The emulator reproduces baryonic suppression in the bispectrum to better than 2% for the 68% percentile across most triangle configurations for k is an element of [0.01, 20] h Mpc(-1) and ensures consistency between cosmological posteriors inferred from second- and third-order weak lensing statistics. These results demonstrate that our emulator meets the high-precision requirements of the Euclid mission for at least the first data release and provides reliable forecasts of the cosmological information contained in the small-scale matter bispectrum. This underscores the potential of emulation techniques to bridge the gap between complex baryonic physics and observational data, maximising the scientific output of Euclid