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Creators/Authors contains: "Alonso, David"

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  1. This paper reviews publications on 5-hydroxymethylfurfural oxidation to 2,5-furandicarboxylic acid over heterogenous catalysts and provides guidelines to improve activity. It covers noble and non-noble metal catalysts in aqueous and organic solvents. 
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    Free, publicly-accessible full text available July 3, 2026
  2. NA (Ed.)
    Pacinian corpuscles detect transient touch and vibration in vertebrates. Corpuscles are composed of a mechanoreceptor afferent surrounded by lamellar Schwann cells (LSCs), enclosed by a multilayered outer core. The spatial arrangement of these components and their contribution to sensory tuning are unclear. We report the three-dimensional architecture of the Pacinian corpuscle and reveal the role of its cellular components in touch detection. In the prevailing model, the outer core acts as a mechanical filter that limits static and low-frequency stimuli from reaching the afferent terminal—the presumed sole site of touch detection. We show that the outer core is dispensable for the sensory tuning to transient touch and vibration; instead, these properties arise from the inner core. By acting as additional touch sensors, LSCs potentiate mechanosensitivity of the terminal, which detects touch via fast inactivating ion channels. Thus, functional tuning of the Pacinian corpuscle is enabled by an interplay between mechanosensitive LSCs and the afferent terminal in the inner core. 
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    Free, publicly-accessible full text available February 28, 2026
  3. Abstract The Atacama Cosmology Telescope Data Release 6 (ACT DR6) power spectrum is expected to provide state-of-the-art cosmological constraints, with an associated need for precise error modeling. In this paper we design, and evaluate the performance of, an analytic covariance matrix prescription for the DR6 power spectrum that sufficiently accounts for the complicated ACT map properties. We use recent advances in the literature to handle sharp features in the signal and noise power spectra, and account for the effect of map-level anisotropies on the covariance matrix. In including inhomogeneous survey depth information, the resulting covariance matrix prescription is structurally similar to that used in thePlanckCosmic Microwave Background (CMB) analysis. We quantify the performance of our prescription using comparisons to Monte Carlo simulations, finding better than 3% agreement. This represents an improvement from a simpler, pre-existing prescription, which differs from simulations by ∼ 16%. We develop a new method to correct the analytic covariance matrix using simulations, after which both prescriptions achieve better than 1% agreement. This correction method outperforms a commonly used alternative, where the analytic correlation matrix is assumed to be accurate when correcting the covariance. Beyond its use for ACT, this framework should be applicable for future high resolution CMB experiments including the Simons Observatory (SO). 
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    Free, publicly-accessible full text available May 1, 2026
  4. Upcoming imaging surveys will allow for high signal-to-noise measurements of galaxy clustering at small scales. In this work, we present the results of the Rubin Observatory Legacy Survey of Space and Time (LSST) bias challenge, the goal of which is to compare the performance of different nonlinear galaxy bias models in the context of LSST Year 10 (Y10) data. Specifically, we compare two perturbative approaches, Lagrangian perturbation theory (LPT) and Eulerian perturbation theory (EPT) to two variants of Hybrid Effective Field Theory (HEFT), with our fiducial implementation of these models including terms up to second order in the bias expansion as well as nonlocal bias and deviations from Poissonian stochasticity. We consider a variety of different simulated galaxy samples and test the performance of the bias models in a tomographic joint analysis of LSST-Y10-like galaxy clustering, galaxy-galaxy-lensing and cosmic shear. We find both HEFT methods as well as LPT and EPT combined with non-perturbative predictions for the matter power spectrum to yield unbiased constraints on cosmological parameters up to at least a maximal scale ofkmax = 0.4 Mpc-1for all samples considered, even in the presence of assembly bias. While we find that we can reduce the complexity of the bias model for HEFT without compromising fit accuracy, this is not generally the case for the perturbative models. We find significant detections of non-Poissonian stochasticity in all cases considered, and our analysis shows evidence that small-scale galaxy clustering predominantly improves constraints on galaxy bias rather than cosmological parameters. These results therefore suggest that the systematic uncertainties associated with current nonlinear bias models are likely to be subdominant compared to other sources of error for tomographic analyses of upcoming photometric surveys, which bodes well for future galaxy clustering analyses using these high signal-to-noise data. 
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  5. Abstract We present a reproduction of thePlanck2018 angular power spectra at ℓ > 30, and associated covariance matrices, for intensity and polarization maps at 100, 143 and 217 GHz. This uses a new, publicly available, pipeline that is part of thePSpipepackage. As a test case we use the same input maps, ancillary products, and analysis choices as in thePlanck2018 analysis, and find that we can reproduce the spectra to 0.1σprecision, and the covariance matrices to 10%. We show that cosmological parameters estimated from our re-derived products agree with the publicPlanckproducts to 0.1σ, providing an independent cross-check of thePlanckteam's analysis. Going forward, the publicly-available code can be easily adapted to use alternative input maps, data selections and analysis choices, for future optimal analysis ofPlanckdata with new ground-based Cosmic Microwave Background data. 
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  6. An enduring question in evolutionary biology concerns the degree to which episodes of convergent trait evolution depend on the same genetic programs, particularly over long timescales. In this work, we genetically dissected repeated origins and losses of prickles—sharp epidermal projections—that convergently evolved in numerous plant lineages. Mutations in a cytokinin hormone biosynthetic gene caused at least 16 independent losses of prickles in eggplants and wild relatives in the genusSolanum. Homologs underlie prickle formation across angiosperms that collectively diverged more than 150 million years ago, including rice and roses. By developing newSolanumgenetic systems, we leveraged this discovery to eliminate prickles in a wild species and an indigenously foraged berry. Our findings implicate a shared hormone activation genetic program underlying evolutionarily widespread and recurrent instances of plant morphological innovation. 
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  7. null (Ed.)
  8. Abstract An enduring question in evolutionary biology concerns the degree to which episodes of convergent trait evolution depend on the same genetic programs, particularly over long timescales. Here we genetically dissected repeated origins and losses of prickles, sharp epidermal projections, that convergently evolved in numerous plant lineages. Mutations in a cytokinin hormone biosynthetic gene caused at least 16 independent losses of prickles in eggplants and wild relatives in the genusSolanum. Strikingly, homologs promote prickle formation across angiosperms that collectively diverged over 150 million years ago. By developing newSolanumgenetic systems, we leveraged this discovery to eliminate prickles in a wild species and an indigenously foraged berry. Our findings implicate a shared hormone-activation genetic program underlying evolutionarily widespread and recurrent instances of plant morphological innovation. 
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  9. null (Ed.)