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    Investigation of the effect of solvation on 1J(Metal–P) spin–spin coupling

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    Funding: Financial support from Slovak Grant Agencies VEGA and APVV (VEGA-2/0135/21, APVV-19-0516 and APVV-22-0488) is acknowledged. MB wishes to thank the EaStCHEM School of Chemistry for support and access to an HPC cluster maintained by Dr H. Früchtl.The solvent effect on the indirect 1J(M–P) spin–spin coupling constant in phosphine selenoether peri-substituted acenaphthene complexes LMCl2 is studied at the PP86 level of nonrelativistic and four-component relativistic density functional theory. Depending on the metal, the solvent effect can amount to as much as 50% or more of the total J-value. This explains the previously found disagreement between the 1J(Hg–P) coupling in LHgCl2, observed experimentally and calculated without considering solvent effects. To address the solvent effect, we have used polarizable continuum and microsolvated models. The solvent effect can be separated into indirect (structural changes) and direct (changes in the electronic structure). These effects are additive, each brings roughly about 50% of the total effect. For the in-depth analysis, we use a model with a lighter metal, Zn, instead of Hg. A much smaller solvent effect on 1J(Hg–P) for a dimer form of LHgCl2 is explained. Pilot calculations of 1J(M–P) couplings in analogous systems with other metals indicate that for metals preferring square planar structures the solvent effect is insignificant because these structures are fairly rigid. Tetrahedral structures are less constrained and can respond more easily to external effects such as solvation.Peer reviewe

    Enantioselective Michael additions using isothiourea catalysis

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    The infrared luminosity of retired and post-starburst galaxies : a cautionary tale for star formation rate measurements

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    Funding: VW acknowledges Science and Technologies Facilities Council (STFC) grants ST/V000861/1 and ST/Y00275X/1. NVA and VW acknowledge the Royal Society and the Newton Fund via the award of a Royal Society–Newton Advanced Fellowship (grant NAF\R1\180403). NVA acknowledges support from Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq). KR acknowledges support from NASA grant 80NSSC23K0495.In galaxies with significant ongoing star formation there is an impressively tight correlation between total infrared luminosity (LTIR) and Hα luminosity (LHα), when Hα is properly corrected for stellar absorption and dust attenuation. This long-standing result gives confidence that both measurements provide accurate estimates of a galaxy’s star formation rate (SFR), despite their differing origins. To test the extent to which this holds in galaxies with lower specific SFR (sSFR=SFR/M*, where M* is the stellar mass), we combine optical spectroscopy from the Sloan Digital Sky Survey (SDSS) with multi-wavelength (FUV to FIR) photometric observations from the Galaxy And Mass Assembly survey (GAMA). We find that LTIR/LHα increases steadily with decreasing Hα equivalent width (WHα, a proxy for sSFR), indicating that both luminosities cannot provide a valid measurement of SFR in galaxies below the canonical star-forming sequence. For both ‘retired galaxies’ and ‘post-starburst galaxies’, LTIR/LHα can be up to a factor of 30 larger than for star-forming galaxies. The smooth change in LTIR/LHα, irrespective of star formation history, ionisation or heating source, dust temperature or other properties, suggests that the value of LTIR/LHα is determined by the balance between star-forming regions and ambient interstellar medium contributing to both LTIR and LHα. It is not a result of the differing timescales of star formation that these luminosities probe. While LHα can only be used to estimate the SFR for galaxies with WHα > 3 Å (sSFR ≳ 10-11.5 /yr), we argue that the mid- and far-infrared can only be used to estimate the SFR of galaxies on the star-forming sequence, and in particular only for galaxies with WHα > 10 Å (sSFR≳ 10-10.5 /yr). We find no evidence for dust obscured star-formation in local post-starburst galaxies.Peer reviewe

    Bonobo gestures, meanings, and context

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    Funding: The author is currently funded by the European Union’s 8th Framework Programme, Horizon 2020, under grant agreement no 802719.Although you might not know what a “gesture” is (yet), most people reading this book probably have some experience with gestures. Waving, bowing, clapping, nodding, pantomiming, and pointing, are just some of the many gestures that you may have encountered. As humans, we use many conventionalized gestures that we learn throughout our lives and regularly produce gestures alongside language (Goldin-Meadow 2005). One way of examining the evolution of human gesture, and potentially human language, is to study gestural communication in other species. Researchers in great ape gestural communication tend to define a gesture as an intentional, mechanically ineffective movement of the limbs, head, or body that is used to communicate (Townsend et al. 2016). All great apes use gestures to communicate (Call and Tomasello 2007), and there is growing evidence of gestural communication across the primate taxa (Macaca mulatta, M. nemestrina, M. arctoides, Maestripieri 2005; Macaca radiata, Gupta and Sinha 2016; Macaca Sylvanus, Hesler and Fischer 2007; Papio anubis, Bourjade et al. 2014)

    HR 10 as seen by CHEOPS and TESS : revealing δ Scuti pulsations, granulation-like signal and hint for transients

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    Funding: CHEOPS is an ESA mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden, and the United Kingdom. The CHEOPS Consortium would like to gratefully acknowledge the support received by all the agencies, offices, universities, and industries involved. Their flexibility and willingness to explore new approaches were essential to the success of this mission. This paper includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST). Funding for the TESS mission is provided by NASA’s Science Mission directorate. We are grateful to V. Antoci for helpful comments. SJAJS has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 833925, project STAREX). VVG is an F.R.S-FNRS Research Associate. SS acknowledges the support from CNES, the Programme National de Planétologie (PNP), and the Programme National de Physique Stellaire (PNPS) of CNRS-INSU. GyMSz acknowledges the support of the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015, a a PRODEX Experiment Agreement No. 4000137122, the Lendület LP2018-7/2021 grant of the Hungarian Academy of Science and the support of the city of Szombathely. ABr was supported by the SNSA. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project Four Aces. SH gratefully acknowledges CNES funding through the grant 837319. SGS acknowledges support from FCT through FCT contract nr. CEECIND/00826/2018 and POPH/FSE (EC). DG gratefully acknowledges financial support from the CRT foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. SC acknowledges financial support from the Centre National d’Etudes Spatiales (CNES, France) and from the Agence Nationale de la Recherche (ANR, France) under grant ANR-17- CE31-0018, funding the INSIDE project. ACC and TW acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. YAl acknowledges the support of the Swiss National Fund under grant 200020_172746. We acknowledge support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grants ESP2016-80435-C2-1-R, ESP2016- 80435-C2-2-R, PGC2018-098153-B-C33, PGC2018-098153-B-C31, ESP2017- 87676-C5-1-R, MDM-2017-0737 Unidad de Excelencia Maria de MaeztuCentro de Astrobiología (INTA-CSIC), as well as the support of the Generalitat de Catalunya/CERCA programme. The MOC activities have been supported by the ESA contract No. 4000124370. SCCB acknowledges support from FCT through FCT contracts nr. IF/01312/2014/CP1215/CT0004. XB, SC, DG, MF and JL acknowledge their role as ESA-appointed CHEOPS science team members. LBo, VNa, IPa, GPi, RRa, GSc, VSi, and TZi acknowledge support from CHEOPS ASI-INAF agreement n. 2019-29-HH.0. ACC acknowledges support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. PEC is funded by the Austrian Science Fund (FWF) Erwin Schroedinger Fellowship, program J4595-N. This project was supported by the CNES. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX Program, and by the University of Liège through an ARC grant for Concerted Research Actions financed by the WalloniaBrussels Federation. LD is an F.R.S.-FNRS Postdoctoral Researcher. This work was supported by FCT – Fundação para a Ciência e a Tecnologia through national funds and by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalizacão by these grants: UID/FIS/04434/2019, UIDB/04434/2020, UIDP/04434/2020, PTDC/FIS-AST/32113/2017 and POCI01-0145-FEDER- 032113, PTDC/FIS-AST/28953/2017 and POCI-01-0145- FEDER-028953, PTDC/FIS-AST/28987/2017 and POCI-01-0145-FEDER028987, O.D.S.D. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. B-OD acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00046. MF and CMP gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18). MG is an F.R.S.-FNRS Senior Research Associate. KGI is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS Guest Observers Programme. She does not participate in, or contribute to, the definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken, nor to any aspect of target selection for the programme. This work was granted access to the HPC resources of MesoPSL financed by the Region Ile de France and the project Equip@Meso (reference ANR-10-EQPX-29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche. ML acknowledges support of the Swiss National Science Foundation under grant number PCEFP2_194576. PM acknowledges support from STFC research grant number ST/M001040/1. This work was also partially supported by a grant from the Simons Foundation (PI Queloz, grant number 327127). IRI acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B- C33, as well as the support of the Generalitat de Catalunya/CERCA programme. NAW acknowledges UKSA grant ST/R004838/1.Context . HR 10 has only recently been identified as a binary system. Previously thought to be an A-type shell star, it appears that both components are fast-rotating A-type stars, each presenting a circumstellar envelope. Although showing complex photometric variability, spectroscopic observations of the metallic absorption lines reveal variation explained by the binarity, but not indicative of debris-disc inhomogeneities or sublimating exocomets. On the other hand, the properties of the two stars make them potential δ Scuti pulsators. Aims . The system has been observed in two sectors by the TESS satellite, and was the target of three observing visits by CHEOPS. Thanks to these new data, we aim to further characterise the stellar properties of the two components. In particular, we aim to decipher the extent to which the photometric variability can be attributed to a stellar origin. In complement, we searched in the lightcurves for transient-type events that could reveal debris discs or exocomets. Methods . We analysed the photometric variability of both the TESS and CHEOPS datasets in detail. We first performed a frequency analysis to identify and list all the periodic signals that may be related to stellar oscillations or surface variability. The signals identified as resulting from the stellar variability were then removed from the lightcurves in order to search for transient events in the residuals. Results . We report the detection of δ Scuti pulsations in both the TESS and CHEOPS data, but we cannot definitively identify which of the components is the pulsating star. In both datasets, we find flicker noise with the characteristics of a stellar granulation signal. However, it remains difficult to firmly attribute it to actual stellar granulation from convection, given the very thin surface convective zones predicted for both stars. Finally, we report probable detection of transient events in the CHEOPS data, without clear evidence of their origin.Peer reviewe

    Thinking with images : An interview with Thomas E. Wartenberg

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    In his most recent book, Thoughtful Images: Illustrating Philosophy Through Art (2023), Thomas E. Wartenberg explores the variety of ways in which visual art has illustrated philosophy. Employing a new framework for thinking about the nature of illustration, Wartenberg surveys a wide variety of cases which, he argues, show not only that philosophical concepts can be illustrated but that such illustrations have the capacity to do philosophy in a substantial way. In this interview, Professor Wartenberg and I discuss the book and its central themes, including the nature and aesthetics of illustration, how art can cultivate philosophical understanding, and how it can contribute unique philosophical insight.Peer reviewe

    Impurity band formation as a route to thermoelectric power factor enhancement in n-type XNiSn half-Heuslers

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    Funding: The EPSRC is acknowledged for support under award EP/N01717X/1, EP/N01703X/1, EP/X02346X/1, EP/L017008/1, EP/R023751/1 and EP/T019298/1 and for a PhD studentship for S.A.B.Bandstructure engineering is a key route for thermoelectric performance enhancement. Here, 20–50% Seebeck (S) enhancement is reported for XNiCuySn half-Heusler samples based on X = Ti. This novel electronic effect is attributed to the emergence of impurity bands of finite extent, due to the Cu dopants. Depending on the dispersion, extent, and offset with respect to the parent material, these bands are shown to enhance S to different degrees. Experimentally, this effect is controllable by the Ti content of the samples, with the addition of Zr/Hf gradually removing the enhancement. At the same time, the mobility remains largely intact, enabling power factors ≥3 mW m−1 K−2 near room temperature, increasing to ≥5 mW m−1 K−2 at high temperature. Combined with reduced thermal conductivity due to the Cu interstitials, this enables high average zT = 0.67–0.72 between 320 and 793 K for XNiCuySn compositions with ≥70% Ti. This work reveals the existence of a new route for electronic performance enhancement in n-type XNiSn materials that are normally limited by their single carrier pocket. In principle, impurity bands can be applied to other materials and provide a new direction for further development.Peer reviewe

    Modality, truth and mere picture thinking

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    Many draw the distinction between truth in, and truth at, a possible world. The latter notion purportedly allows for propositions to be true relative to worlds even if they do not exist relative to those same worlds. Despite its wide application, the distinction is controversial. Some think that the notion of truth at a world is unintelligible. Here, I outline and discuss the most influential argument for the unintelligibility of truth at a world, The Picture Thinking Argument. I outline and defend a neglected strategy to respond to this, arguing that if we take seriously the idea that possible worlds represent total ways the world could be, the distinction can be drawn intelligibly.Peer reviewe

    The tidal deformation and atmosphere of WASP-12b from its phase curve

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    Funding: LCa and CHe acknowledge support from the European Union H2020-MSCA-ITN-2019 under Grant Agreement no. 860470 (CHAMELEON). ACCa and TWi acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. PM acknowledges support from STFC research grant number ST/M001040/1. NAW acknowledges UKSA grant ST/R004838/1.Context. Ultra-hot Jupiters present a unique opportunity to understand the physics and chemistry of planets, their atmospheres, and interiors at extreme conditions. WASP-12 b stands out as an archetype of this class of exoplanets, with a close-in orbit around its star that results in intense stellar irradiation and tidal effects. Aims. The goals are to measure the planet’s tidal deformation, atmospheric properties, and also to refine its orbital decay rate. Methods. We performed comprehensive analyses of the transits, occultations, and phase curves of WASP-12b by combining new CHEOPS observations with previous TESS and Spitzer data. The planet was modeled as a triaxial ellipsoid parameterized by the second-order fluid Love number of the planet, h2, which quantifies its radial deformation and provides insight into the interior structure. Results. We measured the tidal deformation of WASP-12b and estimated a Love number of h2 = 1.55−0.49+0.45 (at 3.2σ) from its phase curve. We measured occultation depths of 333 ± 24 ppm and 493 ± 29 ppm in the CHEOPS and TESS bands, respectively, while the nightside fluxes are consistent with zero, and also marginal eastward phase offsets. Our modeling of the dayside emission spectrum indicates that CHEOPS and TESS probe similar pressure levels in the atmosphere at a temperature of ~2900 K. We also estimated low geometric albedos of Ag = 0.086 ± 0.017 and Ag = 0.01 ± 0.023 in the CHEOPS and TESS passbands, respectively, suggesting the absence of reflective clouds in the high-temperature dayside of the planet. The CHEOPS occultations do not show strong evidence for variability in the dayside atmosphere of the planet at the median occultation depth precision of 120 ppm attained. Finally, combining the new CHEOPS timings with previous measurements refines the precision of the orbital decay rate by 12% to a value of −30.23 ± 0.82 ms yr−1, resulting in a modified stellar tidal quality factor of Q′★ = 1.70 ± 0.14 × 105. Conclusions. WASP-12 b becomes the second exoplanet, after WASP-103b, for which the Love number has been measured from the effect of tidal deformation in the light curve. However, constraining the core mass fraction of the planet requires measuring h2 with a higher precision. This can be achieved with high signal-to-noise observations with JWST since the phase curve amplitude, and consequently the induced tidal deformation effect, is higher in the infrared.Peer reviewe

    Kinetic and thermodynamic characterization of human 4-oxo-L-proline reductase catalysis

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    Funding: This work was supported by a Cunningham Trust Ph.D. Award (Grant PhD-CT-21-04) to R.G.d.S., which supports a Ph.D. studentship to E.P.The enzyme 4-oxo-l-proline reductase (BDH2) has recently been identified in humans. BDH2, previously thought to be a cytosolic (R)-3-hydroxybutyrate dehydrogenase, actually catalyzes the NADH-dependent reduction of 4-oxo-L-proline to cis-4-hydroxy-L-proline, a compound with known anticancer activity. Here we provide an initial mechanistic characterization of the BDH2-catalyzed reaction. Haldane relationships show the reaction equilibrium strongly favors the formation of cis-4-hydroxy-L-proline. Stereospecific deuteration of NADH C4 coupled with mass spectrometry analysis of the reaction established that the pro-S hydrogen is transferred. NADH is co-purified with the enzyme, and a binding kinetics competition assays with NAD+ defined dissociation rate constants for NADH of 0.13 s–1 at 5 °C and 7.2 s–1 at 25 °C. Isothermal titration calorimetry at 25 °C defined equilibrium dissociation constants of 0.48 and 29 μM for the BDH2:NADH and BDH2:NAD+ complexes, respectively. Differential scanning fluorimetry showed BDH2 is highly thermostabilized by NADH and NAD+. The kcat/KM pH–rate profile indicates that a group with a pKa of 7.3 and possibly another with a pKa of 8.7 must be deprotonated and protonated, respectively, for maximum binding of 4-oxo-L-proline and/or catalysis, while the kcat profile is largely insensitive to pH in the pH range used. The single-turnover rate constant is only 2-fold higher than kcat. This agrees with a pre-steady-state burst of substrate consumption, suggesting that a step after chemistry, possibly product release, contributes to limit kcat. A modest solvent viscosity effect on kcat indicates that this step is only partially diffusional. Taken together, these data suggest chemistry does not limit the reaction rate but may contribute to it.Peer reviewe

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