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  1. Dental microwear reflects the abrasiveness of foodstuffs consumed by extant primates and it is commonly used to trace dietary adapta-tions in fossil hominins. However, the impact of feeding events and ecological constraints on micro-scale tooth wear formation processes remain unclear. Here, we use dental buccal-mi-crowear analysis to test age-related effects of physical food processing on tooth-use in a natu-rally accumulated skeletal assemblage from the well-documented population of mountain gorillas from Volcanoes National Park, Rwanda. We analyzed dental microwear pattern of single teeth belonging to individual skeletons: 14 decid-uous m2 (aged 1.2-6.08 years) and 39 permanent molars (~90% M2) of adult gorillas (10.69-44.55 years, 25 males and 14 females). Our results indicate that adult gorillas present more abraded molar buccal surfaces, with significantly higher densities and longer micro-striations, than imma-ture individuals, which reflects the abrasive potential of ingested foods and the micro-stria-tion cumulative process. However, we also found that dental buccal-microwear variability was not associated with age when only adult gorillas were considered. Thus, gorillas from this popula-tion present a stable microwear pattern through adulthood, despite intraindividual variability in feeding ecology. Our findings show the cumulative process of dental buccal-microwear as immature mountain gorillas increase their intake of solid foods and develop an adult diet; but also, the stability of this pattern when diet over time is stable. We confirm that dental buccal-microwear variability is a reasonable proxy for feeding ecology in primates, although seasonality, habitat variability and diet proportions at individual level should be considered in future studies. 
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  2. Yamashita, Y. ; Kano, M. (Ed.)
    Patterned charged membranes with engendered useful characteristics can offer selective transport of electrolytes. Chemical patterning across the membrane surface via a physical inkjet deposition process requires precise control of the reactive-ink formulation, which enables the introduction of charged functionality to the membrane. This study develops a new dynamic mathematical model for the primary step of the batch reactive-ink formulation considering an ink mixture of copper sulphate and ascorbic acid. Nonlinear least squares parameter estimation is performed to infer three kinetic model parameters by analysing data from nine dynamic experiments simultaneously. Global sensitivity and Fisher information matrix (FIM) analyses reveal only one kinetic parameter is identifiable from time-series pH measurements. The fitted model can capture the overall nonlinear dynamics of the batch reaction and works best for initial Cu2 + concentrations between 30 and 50 mM. Time-series Cu2 + or Cu+ concentration measurements are recommended in future experiments to elucidate the kinetics of reactive-ink formulation. 
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  3. Asymptotic giant branch stars are responsible for the production of most of the heavy isotopes beyond Sr observed in the solar system. Among them, isotopes shielded from ther-process contribution by their stable isobars are defined ass-only nuclei. For a long time the abundance ofPb204, the heaviests-only isotope, has been a topic of debate because state-of-the-art stellar models appeared to systematically underestimate its solar abundance. Besides the impact of uncertainties from stellar models and galactic chemical evolution simulations, this discrepancy was further obscured by rather divergent theoretical estimates for the neutron capture cross section of its radioactive precursor in the neutron-capture flow,Tl204(t1/2=3.78yr), and by the lack of experimental data on this reaction. We present the first ever neutron capture measurement onTl204, conducted at the CERN neutron time-of-flight facility n_TOF, employing a sample of only 9 mg ofTl204produced at the Institute Laue Langevin high flux reactor. By complementing our new results with semiempirical calculations we obtained, at thes-process temperatures ofkT8keVandkT30keV, Maxwellian-averaged cross sections (MACS) of 580(168) mb and 260(90) mb, respectively. These figures are about 3% lower and 20% higher than the corresponding values widely used in astrophysical calculations, which were based only on theoretical calculations. By using the newTl204MACS, the uncertainty arising from theTl204(n,γ)cross section on thes-process abundance ofPb204has been reduced from30%down to+8%/6%, and thes-process calculations are in agreement with the latest solar system abundance ofPb204reported by K. Lodders in 2021.

    <supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available July 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10128744-wintertime-north-american-weather-regimes-andthearctic-stratospheric-polar-vortex" itemprop="url"> <span class='span-link' itemprop="name">Wintertime North American Weather Regimes and the Arctic Stratospheric Polar Vortex</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1029/2019GL085592" target="_blank" title="Link to document DOI">https://doi.org/10.1029/2019GL085592  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Lee, S. H.</span> <span class="sep">; </span><span class="author" itemprop="author">Furtado, J. C.</span> <span class="sep">; </span><span class="author" itemprop="author">Charlton‐Perez, A. J.</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2019-12-27">December 2019</time> , Geophysical Research Letters) </span> </div> <div class="actions" style="padding-left:10px;"> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10506229-evaluation-planar-silicon-pixel-sensors-rd53a-readout-chip-phase-upgrade-cms-inner-tracker" itemprop="url"> <span class='span-link' itemprop="name">Evaluation of planar silicon pixel sensors with the RD53A readout chip for the Phase-2 Upgrade of the CMS Inner Tracker</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1088/1748-0221/18/11/P11015" target="_blank" title="Link to document DOI">https://doi.org/10.1088/1748-0221/18/11/P11015  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Adam, W.</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T.</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K.</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M.</span> <span class="sep">; </span><span class="author" itemprop="author">Frühwirth, R.</span> <span class="sep">; </span><span class="author" itemprop="author">Steininger, H.</span> <span class="sep">; </span><span class="author" itemprop="author">Beaumont, W.</span> <span class="sep">; </span><span class="author" itemprop="author">Darwish, M.R.</span> <span class="sep">; </span><span class="author" itemprop="author">Janssen, T.</span> <span class="sep">; </span><span class="author" itemprop="author">Rejeb Sfar, H.</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2023-11-01">November 2023</time> , Journal of Instrumentation) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <title>Abstract

    The Large Hadron Collider at CERN will undergo an upgrade in order to increase its luminosity to 7.5 × 1034cm-2s-1. The increased luminosity during this High-Luminosity running phase, starting around 2029, means a higher rate of proton-proton interactions, hence a larger ionizing dose and particle fluence for the detectors. The current tracking system of the CMS experiment will be fully replaced in order to cope with the new operating conditions. Prototype planar pixel sensors for the CMS Inner Tracker with square 50 μm × 50 μm and rectangular 100 μm × 25 μm pixels read out by the RD53A chip were characterized in the lab and at the DESY-II testbeam facility in order to identify designs that meet the requirements of CMS during the High-Luminosity running phase. A spatial resolution of approximately 3.4 μm (2 μm) is obtained using the modules with 50 μm × 50 μm (100 μm × 25 μm) pixels at the optimal angle of incidence before irradiation. After irradiation to a 1 MeV neutron equivalent fluence of Φeq = 5.3 × 1015 cm-2, a resolution of 9.4 μm is achieved at a bias voltage of 800 V using a module with 50 μm × 50 μm pixel size. All modules retain a hit efficiency in excess of 99% after irradiation to fluences up to 2.1 × 1016 cm-2. Further studies of the electrical properties of the modules, especially crosstalk, are also presented in this paper.

     
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  4. Abstract The Pandora Software Development Kit and algorithm libraries provide pattern-recognition logic essential to the reconstruction of particle interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at ProtoDUNE-SP, a prototype for the Deep Underground Neutrino Experiment far detector. ProtoDUNE-SP, located at CERN, is exposed to a charged-particle test beam. This paper gives an overview of the Pandora reconstruction algorithms and how they have been tailored for use at ProtoDUNE-SP. In complex events with numerous cosmic-ray and beam background particles, the simulated reconstruction and identification efficiency for triggered test-beam particles is above 80% for the majority of particle type and beam momentum combinations. Specifically, simulated 1 GeV/ c charged pions and protons are correctly reconstructed and identified with efficiencies of 86.1 $$\pm 0.6$$ ± 0.6 % and 84.1 $$\pm 0.6$$ ± 0.6 %, respectively. The efficiencies measured for test-beam data are shown to be within 5% of those predicted by the simulation. 
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  5. Abstract The Large Hadron Collider (LHC) at CERN will undergo major upgrades to increase the instantaneous luminosity up to 5–7.5×10 34 cm -2 s -1 . This High Luminosity upgrade of the LHC (HL-LHC) will deliver a total of 3000–4000 fb -1 of proton-proton collisions at a center-of-mass energy of 13–14 TeV. To cope with these challenging environmental conditions, the strip tracker of the CMS experiment will be upgraded using modules with two closely-spaced silicon sensors to provide information to include tracking in the Level-1 trigger selection. This paper describes the performance, in a test beam experiment, of the first prototype module based on the final version of the CMS Binary Chip front-end ASIC before and after the module was irradiated with neutrons. Results demonstrate that the prototype module satisfies the requirements, providing efficient tracking information, after being irradiated with a total fluence comparable to the one expected through the lifetime of the experiment. 
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