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Item type:Publication, Tree diversity is changing across tropical Andean and Amazonian forests in response to global change(Nature Portfolio, 2026-02-01)Climate and atmospheric changes are impacting forest function and structure worldwide, but their effects on tropical forest diversity are unclear. Nowhere is the scientific challenge greater than in the Andes and the Amazon, which together include the world's most diverse forests. Here, using 406 permanent plots spanning four decades of intact lowland and montane forest dynamics, we test for long-term change in species richness and assess the influence of climate and other variables. We show that, at a continental scale, species richness appears stable, but this masks substantial regional variation. Species richness increased in Northern Andean and Western Amazon plots, yet declined in the Central Andes, Guyana Shield and Central-Eastern Amazon. Overall, warmer, drier and more seasonal forests lost species, while those at higher elevations, in less fragmented areas and with faster rates of tree turnover experienced increases. Region-specific drivers, particularly precipitation seasonality and demographic factors, modulated these trends. The results highlight the diverse ways in which Amazon-Andes forests are changing and underscore the critical need to preserve large-scale ecosystem integrity to maintain local tree diversity. By doing so, Northern Andean forests in particular could serve as an important refuge for species increasingly displaced by climate change.1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Quantifying the Influence of Supercritical Drying on the Pore Size Distribution of Cobalt-Doped Silica Membrane(American Chemical Society, 2026-06-15)Microporous silica membranes offer significant potential for hydrogen (H 2 ) separation. However, the separation performance of such membranes has been critically limited by membrane pore defects due to traditional evaporation-drying methods. In evaporation-drying methods, surface tension creates cohesion-adhesion imbalances, causing non-uniform solvent removal and capillary force to create defects, thereby supporting non-selective gas permeation. This study proposes a novel supercritical-drying technique that reduces non-selective pathways by facilitating the removal of solvents without surface tension. For this purpose, cobalt-doped silica membranes were fabricated on ?-alumina substrates and subjected to either supercritical-drying or the evaporation-drying method. The membranes were evaluated for He and N 2 single-gas permeance over a temperature range of 200–500 °C. To understand the effect of drying method on the transport mechanism, experimental permeance and activation energy ( E a ) data were combined into a transport modeling framework to establish the most representative pore size distribution (PSD) of silica membranes. The validity of the reconstructed PSD was confirmed by the close correspondence between the modeled and experimental E a and gas permeance values. Further results showed that the supercritical-dried membrane exhibited a higher proportion of 5–6-member siloxane rings (98.75%) and a lesser contribution of 7- to 9-membered rings than the evaporation-dried membrane, indicating a compact and homogeneous microporous structure. Additionally, structural improvement in the supercritical-dried membrane gave rise to ten times reduced Knudsen flow contributions than the evaporation-dried membrane. This work proves that controlled drying techniques can tune subnanometer pore structure and provide a predictive pathway to design high-performance silica membranes. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Katydids Shift to Higher-Stability Gaits when Climbing Inclined Substrates(Oxford University Press, 2025-12-01)When terrestrial organisms locomote in natural settings, they must navigate complex surfaces that vary in incline angles and substrate roughness. Variable surface structures are common in arboreal environments and can be challenging to traverse. This study examines the walking gait of katydids (Tettigoniidae) as they traverse a custom-built platform with varying incline angles ($30^\circ$, $45^\circ$, $60^\circ$, $75^\circ$, $90^\circ$) and substrate roughness (40, 120, and 320 grit sandpaper). Our results show that katydids walk more slowly as the incline angle increases and as katydid mass increases, with a decrease of around 0.3 body lengths per second for every 1$^\circ$ increase in incline. At steeper inclines and larger sizes, katydids are also less likely to use an alternating tripod gait, opting instead to maintain more limbs in contact with the substrate during walking. Katydids also increased average duty factor when climbing steeper inclines and with increasing body mass. However, substrate roughness did not affect walking speed or gait preference in our trials. These findings provide insights into how environmental factors influence locomotor strategies in katydids and enhance our understanding of effective locomotor strategies in hexapods.2 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Higher-order symmetry plane correlations in Pb-Pb collisions at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:msub> <mml:mi>s</mml:mi> <mml:mrow> <mml:mi>N</mml:mi> <mml:mi>N</mml:mi> </mml:mrow> </mml:msub> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>5.02</mml:mn> <mml:mspace width="0.28em"/> <mml:mi>TeV</mml:mi> </mml:mrow> </mml:math>(American Institute of Physics Inc., 2025-05-30)The correlations between event-by-event fluctuations of symmetry planes are measured in Pb-Pb collisions at a center-of-mass energy per nucleon pair <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mrow> <a:msqrt> <a:msub> <a:mi>s</a:mi> <a:mrow> <a:mi>N</a:mi> <a:mi>N</a:mi> </a:mrow> </a:msub> </a:msqrt> <a:mo>=</a:mo> <a:mn>5.02</a:mn> <a:mspace width="0.28em"/> <a:mi>TeV</a:mi> </a:mrow> </a:math> recorded by the ALICE detector at the Large Hadron Collider. This analysis is conducted using the Gaussian estimator technique, which is insensitive to biases from correlations between different flow amplitudes. The study presents, for the first time, the centrality dependence of correlations involving up to five different symmetry planes. The correlation strength varies depending on the harmonic order of the symmetry plane and the collision centrality. Comparisons with measurements from lower energies indicate no significant differences within uncertainties. Additionally, the results are compared with hydrodynamic model calculations. Although the model predictions provide a qualitative explanation of the experimental results, they overestimate the data for some observables. This is particularly true for correlators that are sensitive to the nonlinear response of the medium to initial-state anisotropies in the collision system. As these new correlators provide unique information—independent of flow amplitudes—their usage in future model developments can further constrain the properties of the strongly interacting matter created in ultrarelativistic heavy-ion collisions.6 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, First measurement of symmetric cumulants of hexagonal flow harmonics in Pb-Pb collisions at √sNN = 5.02 TeV(American Institute of Physics Inc., 2025-08-18)Correlations between event-by-event fluctuations of anisotropic flow harmonics are measured in Pb-Pb collisions at a center-of-mass energy per nucleon pair of 5.02 TeV, as recorded by the ALICE detector at the LHC. This study presents correlations up to the hexagonal flow harmonic <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:msub> <a:mi>v</a:mi> <a:mn>6</a:mn> </a:msub> </a:math> , which was measured for the first time. The magnitudes of these higher-order correlations are found to vary as a function of collision centrality and harmonic order. These measurements are compared to viscous hydrodynamic model calculations with EKRT initial conditions and to the iEBE-VISHNU model with <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"> <b:msub> <b:mi mathvariant="normal">T</b:mi> <b:mi mathvariant="normal">R</b:mi> </b:msub> <b:mi>ENTo</b:mi> </b:math> initial conditions. The observed discrepancies between the data and the model calculations vary depending on the harmonic combinations. Due to the sensitivity of model parameters estimated with Bayesian analyses to these higher-order observables, the results presented in this work provide new and independent constraints on the initial conditions and transport properties in theoretical models used to describe the system created in heavy-ion collisions.5 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Determining exciton binding energy and reduced effective mass in metal tri-halide perovskites from optical and impedance spectroscopy measurements(American Physical Society, 2025-10-10)This work presents a new method to accurately determine exciton binding energy and reduced effective mass in bulk halide perovskites by accounting for polarization effects from carrier-phonon interactions. The exciton-polaron binding energy is estimated using optical absorption measurements and the Elliott-based Band Fluctuations (EBF) model. The reduced effective mass is then derived by combining the results from the EBF model with the Pollmann-Buettner exciton-polaron theory, which incorporates electron-phonon coupling by leaving in consideration the ionic and electronic dielectric responses, as well as the LO phonon energy. When applied to $A\phantom{\rule{0}{0ex}}B\phantom{\rule{0}{0ex}}{X}_{3}$ perovskites ($A$ = MA, FA, Cs; $B$ = Pb; $X$ = I, Br, Cl), this approach shows excellent agreement with magnetoabsorption and other optical-resolved methods, confirming its accuracy and broad applicability which could be extended to other polar systems.4