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GATA-3 localization shapes lymphocyte function
No full textDespite the crucial roles of GATA-3 in lymphocyte biology, little is known about its intracellular distribution and the mechanisms regulating its nuclear import. Single-cell analyses on confocal microscopy images revealed that GATA-3 was enriched in the nucleus of naive and T helper (Th)2 cells, whereas Th1 cells preferentially accumulated it in the cytoplasm. This GATA-3 compartmentalization was mirrored in innate lymphoid cells ex vivo. In vitro or in vivo reprogramming of Th1 and Th2 cells reversed the subset-specific GATA-3 localization and triggered the acquisition or loss of GATA-3-dependent effector functions, respectively. We identified importin-β as the transporter mediating GATA-3’s nuclear import. In Th2 cells, the subtle cytoplasmic accumulation of GATA-3 following importin-β blockade disrupted the GATA-3 autoactivation loop and impeded type 2 cell features. This sensitivity was explained by the prompt nuclear degradation of GATA-3, thus emphasizing that Th2 cell function depends on continuous and maximal nuclear import of GATA-3. Our results highlight the control of GATA-3 import into the nucleus as a fundamental rheostat of lymphocyte biology
Shared universal pressures in the evolution of human languages
No full textDespite the great diversity of human languages, recurring grammatical patterns (termed ‘universals’) have been found. Using the Grambank database of more than 2,000 languages, spatiophylogenetic analyses reveal that while only a third of 191 putative universals have robust statistical support, there are still preferred feature configurations that have evolved repeatedly — consistent with shared cognitive and communicative pressures having shaped the evolutionary dynamics of languages
A canonical generator for congruence ideals of Hida families
No full textWe construct adjoint p-adic L-functions generating the congruence ideal attached toHida families. These functions interpolate the Petersson norm of any classical ordinary newform, normalized by a product of Shimura’s canonical periods. We show that, after adjusting by suitable Euler factors, they are interpolated by a regular element of Hida’s universal ordinary Hecke algebra. We also establish a link between these p-adic L-functions and the characteristic series of primitive adjoint Selmer groups
Comparability of liquid chromatography tandem mass spectrometry analysis of dissolved organic matter across laboratories
No full textHigh Deuteration of Methanol in L1544
No full textIsotopic fractionation is a very powerful tool to follow the evolution of material from one stage to the next in the star-formation process. Prestellar cores exhibit some of the highest levels of deuteration because their physical conditions (T = 105 cm-3) greatly favor deuteration processes. Deuteration maps are a measure of the effectiveness of the deuteration across the core, and they are useful to study both the deuteration and the formation mechanism (either in the gas-phase or on grain surfaces) of the main species. Methanol is the simplest complex organic molecule (COM) that is O-bearing and detected in the interstellar medium (ISM). It represents the beginning of molecular complexity in star-forming regions; thus, a complete understanding of its formation and deuteration is a necessary step to understand the development of further chemical complexity. In this paper, we use single-dish observations with the IRAM 30 m telescope and state-of-the-art chemical models to investigate the deuteration of methanol toward the prototypical prestellar core L1544. We also compare the results of the chemical models with previous observations of deuterated methanol toward the presttellar cores HMM1 and L694-2. The spectra extracted from the CHD2OH map show that the emission is concentrated in the center and toward the northwest of the core. Using deep observations toward the dust and the methanol peaks of the core, we derive a very large deuterium fraction for methanol (similar to 20%) toward both peaks. The comparison of our observational results with chemical models has highlighted the importance of H-abstraction processes in the formation and deuteration of methanol. Deep observations combined with state-of-the-art chemical models are of fundamental importance in understanding the development of molecular complexity in the ISM. Our analysis also shows the importance of non-LTE effects when measuring the D/H ratios in methanol
Multimodal atmospheric characterization of β Pictoris b Adding high-resolution continuum spectra from GRAVITY
No full textContext. Characterizations of giant exoplanets such as beta Pictoris b (hereafter beta Pic b) are now routinely performed with multiple spectrographs and imagers exploring different spectral bandwidths and resolutions, allowing for atmospheric retrieval of spectra with or without the conservation of the planet spectral continuum. The accounting of data multimodality in the analysis could provide a more comprehensive determination of the planets physical and chemical properties and inform on their formation history. Aims. We present the first VLTI observations at R-lambda similar to 4000 of beta Pic b obtained for an exoplanet with GRAVITY at such a high resolution. We upgraded the forward modelling code ForMoSA to account for the data multimodality, including low-, medium-, and high-resolution spectroscopy based on both a direct model-data comparison and an analysis of cross-correlation signals. We used the ForMoSA code to refine the constraints on the atmospheric properties of the exoplanet and evaluated the sensitivity of the retrieved values to the input dataset. Methods. We obtained four high-signal-to-noise (S/N similar to 20) spectra of beta Pic b in the K band with GRAVITY at R-lambda similar to 4000 conserving both the pseudo-continuum and the pattern of molecular absorptions. We used ForMoSA with four grids of self-consistent forward models (Exo-REM, ATMO, BT-Settl, and Sonora) to explore different T-eff, log(g), metallicity, C/O, and (CO)-C-12/(CO)-C-13 ratio values. We then combined the GRAVITY spectra with published 1-5 mu m photometry (NaCo, VisAO, NICI, and SPHERE), low-to-mediumresolution (R-lambda <= 700 broadband, 0.9-7 mu m) spectra, and echelle spectra covering narrower bandwidths (R-lambda similar to 100 000, 2.1-5.2 mu m). Results. Sonora and Exo-REM are statistically preferred among all four models, regardless of the dataset used. Exo-REM predicts T-eff = 1607.45(-6.20)(+4.85) K and log(g) = 4.46(-0.04)(+0.02) dex when using only the GRAVITY epochs, whereas we have T-eff = 1502.74(-2.14)(+2.32) K log(g) = 4.00 +/- 0.01 dex when incorporating all available datasets. The inclusion of archival data significantly affects all retrieved posteriors. When using all datasets, C/O mostly remains solar (0.552(-0.002)(+0.003)), while [M/H] reaches super-solar values (0.50 +/- 0.01). We report the first tentative constraint on the isotopic ratio log((CO)-C-12/(CO)-C-13) = 1.12(-0.08)(+0.11) in beta Pic b's atmosphere; however, we note that this detection remains inconclusive due to telluric residuals affecting both the GRAVITY and SINFONI data. Additionally, we estimated the bolometric luminosity as log(L/L-circle dot) = -4.01(-0.05)(+0.04) dex. Using a system age of 23 +/- 3 Myr, along with this bolometric luminosity and the constraints on the dynamical mass of beta Pic b, we were able to constrain the maximum of heavy element content of the planet to be on the order of 5% (20-80 M-Earth). Conclusions. The joint access to the pseudo-continuum and molecular lines in the K band provided by GRAVITY have a significant impact on the retrieved metallicity, possibly owing to the collision-induced absorption driving the continuum shape of the K band. The echelle spectra do not dominate the final fit with respect to lower resolution data covering a broader portion of the spectral energy distribution and the latter keeps encapsulating more robust information on T-eff. Future multimodal frameworks should include a weighting scheme to account for the bandwidth and central wavelength of the observations
Possibilities and limitations of thermal infrared detections of the Chelyabinsk progenitor and 2024 YR4 before Earth encounters
No full textWe investigate the feasibility of detecting decameter-scale objects on day-side trajectories in infrared wavelengths from space, prior to their close encounters with Earth. Specifically, we examine a 20-m object on a Chelyabinsk-progenitor orbit (Jan/Feb 2013) and the 60-m potentially hazardous asteroid 2024 YR4 (Nov/Dec 2024 & 2032) during their respective approaches to the Earth-Moon system. Considering the solar elongation constraints of the NEO Surveyor and NEOMIR missions (both located at L1), along with an assumed detection threshold of 100 mu Jy at 8 mu m, we find that both missions would be capable of detecting the objects - hours in advance with NEO Surveyor and several days ahead with NEOMIR. We also address limiting factors such as the elevated infrared sky background due to zodiacal dust emission and the high apparent motion of targets near Earth. Finally, we discuss the challenges associated with observing and modeling asteroids at low solar elongation and large phase angles, where we lack good-quality IR validation data
X-ray, optical, and radio follow-up of five thermally emitting isolated neutron star candidates
No full textWe report on follow-up observations with XMM-Newton, the FORS2 instrument at the ESO-VLT, and FAST, aiming to characterise the nature of five thermally emitting isolated neutron star (INS) candidates recently discovered from searches in the footprint of the Spectrum Roentgen Gamma (SRG)/eROSITA All-sky Survey. We find that the X-ray spectra are predominantly thermal and can be described by low-absorbed blackbody models with effective temperatures ranging from 50 to 210 eV. In two sources, the spectra also show narrow absorption features at 300-400 eV. Additional non-thermal emission components are not detected in any of the five candidates. The soft X-ray emission, the absence of optical counterparts in four sources, and the consequent large X-ray-to-optical flux ratios > 3000 - 5400 confirm their INS nature. For the remaining source, eRASSU J144516.0-374428, the available data do not allow a confident exclusion of an active galactic nucleus nature. However, if the source is Galactic, the small inferred X-ray emitting region is reminiscent of a heated pulsar polar cap, possibly pointing to a binary pulsar nature. X-ray timing searches do not detect significant modulations in all candidates, implying pulsed fraction upper limits of 13-19% (0.001-13.5 Hz). The absence of pulsations in the FAST observations targeting eRASSU J081952.1-131930 and eRASSU J084046.2-115222 excludes periodic magnetospheric emission at 1-1.5 GHz with an 8 sigma significance down to 4.08 mu Jy and 2.72 mu Jy, respectively. The long-term X-ray emission of all sources does not imply significant variability. Additional observations are warranted to establish exact neutron star types. At the same time, the confirmation of the predominantly thermal neutron star nature in four additional sources highlights the power of SRG/eROSITA to complement the Galactic INS population
Introduction: Toward a Global History of Soil: Sciences, Practices, and Materialities, 1300–1750
No full textTwo-dimensional (2D)/2D heterostructures based on carbonaceous nanomaterials for electrocatalysis
No full textOver the past few decades, 2D nanomaterials have been extensively developed for heterogeneous electrocatalysis and energy storage owing to their tunable physicochemical and electronic properties. The development of efficient synthetic routes has enabled the combination of different 2D materials into 2D/2D heterostructures, offering an additional level of property optimization. Despite remarkable progress in constructing such 2D carbonaceous heterostructures that merge the advantages of individual components, several intrinsic limitations still hinder the attainment of ideal performance. In these systems, interfacial interactions and synergistic effects play decisive roles in governing electrochemical behavior. Herein, 2D heterostructures derived from carbonaceous nanomaterials for representative electrocatalytic applications are reviewed. Recent advances in pristine 2D carbonaceous nanomaterials are summarized, including synthetic strategies, compositional tuning, and electrochemical functions. Next, the nature of interfacial interactions and synergistic effects within 2D heterostructures is discussed, followed by an overview of fabrication approaches and emerging electrocatalytic applications. Finally, we highlight current challenges and outline promising directions for future research in advanced energy conversion systems