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Judith Korth joins the podcast this week and tell us about how she found her way into astronomy research, how she ended up here at Lund University and how she now studies distant worlds far beyond our own Solar System.In this third season we are also including some Cosmic Curiosities. These are some ideas, events or trivia from astronomic history that Ross, Victor and Lucian feel are worth bringin

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Context. Until now, heavy interstellar extinction has meant that only a few studies of chemical abundances have been possible in the inner Galactic bulge. However, it is crucial to learn more about this structure in order to better understand the formation and evolution of the centre of the Galaxy and galaxies in general. Aims. In this paper, we aim to derive high-precision α-element abundances us

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Dihydropyrimidinase (DHPase) is a key enzyme in the pyrimidine pathway, the catabolic route for synthesis of β-amino acids. It catalyses the reversible conversion of 5,6-dihydrouracil (DHU) or 5,6-dihydrothymine (DHT) to the corresponding N-carbamoyl-β-amino acids. This enzyme has the potential to be used as a tool in the production of β-amino acids. Here, the reaction mechanism and origin of ster

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Learning by teaching someone else has proven to be beneficial in both human-human and human-agent interaction. Instructing someone else, that is, taking the role as a tutor, has a series of positive effects on students' learning and performance. For example, the fact that someone else is in need of help seems to affect students to put more effort into the task at hand, trying harder, being more th

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Nitrogenase is the only enzyme that can convert N2 into NH3. The reaction requires the addition of eight electrons and protons to the enzyme and the mechanism is normally described by nine states, E0–E8, differing in the number of added electrons. Experimentally, it is known that three or four electrons need to be added before the enzyme can bind N2. We have used combined quantum mechanical and mo

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The efficiency with which flying animals convert metabolic power to mechanical power dictates an individual's flight behaviour and energy requirements. Despite the significance of this parameter, we lack empirical data on conversion efficiency for most species as in vivo measurements are notoriously difficult to obtain. Furthermore, conversion efficiency is often assumed to be constant across flig

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Molecular dynamics (MD) simulations are a powerful approach to studying the structure and dynamics of proteins related to health and disease. Advances in the MD field allow modeling proteins with high accuracy. However, modeling metal ions and their interactions with proteins is still challenging. NPL4 is a zinc-binding protein and works as a cofactor for p97 to regulate protein homeostasis. NPL4

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Astroglial dysfunction contributes to the pathogenesis of Huntington s disease (HD), and glial replacement can ameliorate the disease course. To establish the topographic relationship of diseased astrocytes to medium spiny neuron (MSN) synapses in HD, we used 2-photon imaging to map the relationship of turboRFP-Tagged striatal astrocytes and rabies-Traced, EGFP-Tagged coupled neuronal pairs in R6/

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Observations of binaries containing pairs of neutron stars using the upcoming space-based gravitational wave observatory, LISA, have the potential to improve our understanding of neutron star physics and binary evolution. In this work, we assess the effect of changing the model of the Milky Way’s kinematics and star formation history on predictions of the population of double neutron stars that wi

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Cross-correlation spectroscopy is an invaluable tool in the study of exoplanets. However, aliasing between spectral lines makes it vulnerable to systematic biases. This work strives to constrain the aliases of the cross-correlation function to provide increased confidence in the detections of elements in the atmospheres of ultra-hot Jupiters (UHJs) observed with high-resolution spectrographs. We u

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We present a new suite of cosmological zoom-in hydrodynamical (≈ 20 pc spatial resolution) simulations of Milky-Way mass galaxies to study how a varying mass ratio for a Gaia-Sausage-Enceladus (GSE) progenitor impacts the z = 0 chemodynamics of halo stars. Using the genetic modification approach, we create five cosmological histories for a Milky-Way-mass dark matter halo (M200 ≈ 1012 M☉), incremen

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The formation and evolution of galaxies have proved sensitive to the inclusion of stellar feedback, which is therefore crucial to any successful galaxy model. We present INFERNO, a new model for hydrodynamic simulations of galaxies, which incorporates resolved stellar objects with star-by-star calculations of when and where the injection of enriched material, momentum, and energy takes place. INFE

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Recent observations of high-redshift galactic disks (z ≈ 1-3) show a strong negative trend in the dark-matter (DM) fraction f DM with increasing baryon surface density. For this to be true, the inner baryons must dominate over DM in early massive galaxies, as observed in the Milky Way today. If disks are dominant at early times, we show that stellar bars form promptly within these disks, leading t

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[4Fe–4S] clusters are essential cofactors in many proteins involved in biological redox-active processes. Density functional theory (DFT) methods are widely used to study these clusters. Previous investigations have indicated that there exist two local minima for these clusters in proteins. We perform a detailed study of these minima in five proteins and two oxidation states, using combined quantu

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The abundance of refractory elements in giant planets can provide key insights into their formation histories1. Owing to the low temperatures of the Solar System giants, refractory elements condense below the cloud deck, limiting sensing capabilities to only highly volatile elements2. Recently, ultra-hot giant exoplanets have allowed for some refractory elements to be measured, showing abundances

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Context. β Pictoris is a young nearby system hosting a well-resolved edge-on debris disk, along with at least two exoplanets. It offers key opportunities for carrying out detailed studies of the evolution of young planetary systems and their shaping soon after the end of the planetary formation phase. Aims. We analyzed high-contrast coronagraphic images of this system, obtained in the mid-infrared

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Charge regulation is fundamental in most chemical, geochemical, and biochemical systems. Various mineral surfaces and proteins are well-known to change their charge state as a function of the activity of the hydronium ions, that is, the pH. Besides being modulated by the pH, the charge state is sensitive to salt concentration and composition due to screening and ion correlations. Given the importa

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We have designed a [Fe(SH)4H]− model with the fifth proton binding either to Fe or S. We show that the energy difference between these two isomers (∆E) is hard to estimate with quantum-mechanical (QM) methods. For example, different density functional theory (DFT) methods give ∆E estimates that vary by almost 140 kJ/mol, mainly depending on the amount of exact Hartree–Fock included (0%–54%). The m