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A novel photodetecting device architecture that combines the optoelectronic property advantages of a perovskite and the amplification properties of a Si metal–oxide–semiconductor field‐effect transistor (MOSFET) to innovate a photodetecting system with ultrahigh sensitivity, especially in low‐light intensity, is demonstrated. This perovskite‐based MOSFET photodetector (PM‐PD) can respond as low as 116 nW cm−2 with extremely high responsivity 4200 A W−1. The perovskite is part of the gate dielectric to modulate the MOSFET drain current when the light intensity is changed. A direct bandgap, organic–inorganic hybrid halide perovskite with a large optical absorption coefficient, can enhance photodetector performance. However, perovskite materials are not good conductors for transporting photogenerated electrons and holes compared with single‐crystal silicon. Therefore, the perovskite was utilized as a dielectric where the capacitance is used instead. In the proposed PM‐PD architecture, changing the width‐to‐length (W/L) ratio of perovskite capacitor electrodes, can modulate the dark current from picoamperes to microamperes providing a tunable parameter for optimizing photodetecting performance. Furthermore, the capacitance of the perovskite can be modulated by frequency, which facilitates matching the capacitance of perovskite and MOSFET gate oxide—another important requirement for optimal photodetecting performance. Finally, our novel PM‐PD is commensurate with potential 3D monolithic integration.

Photonic crystals have been widely investigated since they have great potential to manipulate the flow of light in an ultra-compact-scale and enable numerous innovative applications. 2D slab photonic crystals for the telecommunication C band at around 1550 nm have multi-scale structures that are typically micron-scale waveguides and deep sub-micron-scale air hole arrays. Several steps of nanolithography and photolithography are usually used for the fabrication of multi-scale photonic crystals. In this work, we report a one-step lithography process to pattern both micron and deep sub-micron features simultaneously for the 2D slab photonic crystal using combined-nanoimprint-and-photolithography. As a demonstrator, a 2D silicon photonic crystal transverse magnetic (TM) polarizer was fabricated, and the operation was successfully demonstrated.

Abstract Herbivorous insects alter biogeochemical cycling within forests, but the magnitude of these impacts, their global variation, and drivers of this variation remain poorly understood. To address this knowledge gap and help improve biogeochemical models, we established a global network of 74 plots within 40 mature, undisturbed broadleaved forests. We analyzed freshly senesced and green leaves for carbon, nitrogen, phosphorus and silica concentrations, foliar production and herbivory, and stand-level nutrient fluxes. We show more nutrient release by insect herbivores at non-outbreak levels in tropical forests than temperate and boreal forests, that these fluxes increase strongly with mean annual temperature, and that they exceed atmospheric deposition inputs in some localities. Thus, background levels of insect herbivory are sufficiently large to both alter ecosystem element cycling and influence terrestrial carbon cycling. Further, climate can affect interactions between natural populations of plants and herbivores with important consequences for global biogeochemical cycles across broadleaved forests.

We describe a novel biosafety aerosol chamber equipped with state-of-the-art instrumentation for bubble-bursting aerosol generation, size distribution measurement, and condensation-growth collection to minimize sampling artifacts when measuring virus infectivity in aerosol particles. Using this facility, we investigated the effect of relative humidity (RH) in very clean air without trace gases (except ∼400 ppm CO2) on the preservation of influenza A virus (IAV) infectivity in saline aerosol particles. We characterized infectivity in terms of 99%-inactivation time, t99, a metric we consider most relevant to airborne virus transmission. The viruses remained infectious for a long time, namely t99 > 5 h, if RH < 30% and the particles effloresced. Under intermediate conditions of humidity (40% < RH < 70%), the loss of infectivity was the most rapid (t99 ≈ 15–20 min, and up to t99 ≈ 35 min at 95% RH). This is more than an order of magnitude faster than suggested by many previous studies of aerosol-borne IAV, possibly due to the use of matrices containing organic molecules, such as proteins, with protective effects for the virus. We tested this hypothesis by adding sucrose to our aerosolization medium and, indeed, observed protection of IAV at intermediate RH (55%). Interestingly, the t99 of our measurements are also systematically lower than those in 1-μL droplet measurements of organic-free saline solutions, which cannot be explained by particle size effects alone.

ABSTRACT The composition of respiratory fluids influences the stability of viruses in exhaled aerosol particles and droplets, though the role of respiratory organics in modulating virus stability remains poorly understood. This study investigates the effect of organic compounds on the stability of influenza A virus (IAV) in deposited droplets. We compare the infectivity loss of IAV at different relative humidities (RHs) over the course of 1 h in 1-µL droplets consisting of phosphate-buffered saline (without organics), synthetic lung fluid, or nasal mucus (both containing organics). We show that IAV stability increases with increasing organic:salt ratios. Among the various organic species, proteins are identified as the most protective component, with smaller proteins stabilizing IAV more efficiently at the same mass concentration. Organics act by both increasing the efflorescence RH and shortening the drying period until efflorescence at a given RH. This research advances our mechanistic understanding of how organics stabilize exhaled viruses and thus influence their inactivation in respiratory droplets.IMPORTANCEThis study investigates how the composition of respiratory fluids affects the stability of viruses in exhaled droplets. Understanding virus stability in droplets is important as it impacts how viruses spread and how we can combat them. We focus on influenza A virus (IAV) and investigate how different organic compounds found in lung fluid and nasal mucus protect the virus from inactivation. We demonstrate that the ratio of organics to salt in the fluid is an indicator of IAV stability. Among organics, small proteins are particularly effective at protecting IAV. Their effect is in part explained by the proteins’ influence on the crystallization of salts in the droplets, thereby shielding the viruses from prolonged exposure to harmful salt concentrations. Understanding these mechanisms helps us grasp how viruses sustain their infectivity over time in respiratory droplets, contributing to efforts in controlling infectious diseases.

Resumen Se llevó a cabo una investigación cuyo objetivo esencial fue determinar la relación existente entre la autoeficacia y el pensamiento crítico en estudiantes de Educación Superior de una Universidad de Lima Metropolitana. Con este fin, se aplicó a una muestra de 50 alumnos de Educación Superior dos instrumentos de evaluación psicológica elaborados con tales propósitos: Inventario de Expectativas de Autoeficacia Académica de Barraza (2010) y la Encuesta de Capacidad de Pensamiento Crítico de Córdova (2021). Ambos instrumentos contaban con la debida validez y confiabilidad comprobada para nuestro medio. Estos instrumentos se aplicaron a una muestra seleccionada mediante muestreo no-probabilístico, de tipo criterial u opinático. Metodológicamente, se trató de una investigación descriptiva explicativa de nivel correlacional, con enfoque cuantitativo, de diseño no-experimental, de corte transversal, que aplicó la estadística paramétrica (Correlación Producto – Momento de Pearson) porque así lo estableció la Prueba de Kolmogorov – Smirnorv, para determinar la normalidad o no de las puntuaciones recabadas. El procedimiento estadístico corrió a cargo del Programa Excel 365 y del Programa SPSS Versión 25 para Windows y permitió comprobar las hipótesis planteadas, en el sentido que existía una relación directa y significativa (p= 0.001) entre las variables consideradas. En tal sentido se plantearon las conclusiones y las respectivas recomendaciones. Se elaboraron y presentaron complementariamente, las respectivas tablas y gráficos estadísticos. Palabras clave: Autoeficacia, Desarrollo del Pensamiento Crítico, Educación Superior.

Abstract One mechanism proposed to explain high species diversity in tropical systems is strong negative conspecific density dependence (CDD), which reduces recruitment of juveniles in proximity to conspecific adult plants. Although evidence shows that plant-specific soil pathogens can drive negative CDD, trees also form key mutualisms with mycorrhizal fungi, which may counteract these effects. Across 43 large-scale forest plots worldwide, we tested whether ectomycorrhizal tree species exhibit weaker negative CDD than arbuscular mycorrhizal tree species. We further tested for conmycorrhizal density dependence (CMDD) to test for benefit from shared mutualists. We found that the strength of CDD varies systematically with mycorrhizal type, with ectomycorrhizal tree species exhibiting higher sapling densities with increasing adult densities than arbuscular mycorrhizal tree species. Moreover, we found evidence of positive CMDD for tree species of both mycorrhizal types. Collectively, these findings indicate that mycorrhizal interactions likely play a foundational role in global forest diversity patterns and structure.

The UN 2030 Agenda for Sustainable Development Goal 15, termed Life on Land, is monitored by indicators and sub-indicators that largely deal with forest extent. In countries with structurally complex and species-rich forests, indicators and sub-indicators of forest quality are also needed to effectively monitor and sustain ecological integrity. The goal of the paper is to demonstrate the use of complementary sub-indicators of forest quality for SDG15 reporting and conservation planning. Our objective is to apply these sub-indicators within Colombia, Ecuador, and Peru and evaluate spatial patterns and trends over time as a basis for revealing how the results complement the official indicators of forest extent and forest extent in protected areas in informing conservation. The sub-indicators of forest quality quantify naturalness, riparian forest, forest structure and integrity, forest fragmentation, and forest connectivity. We quantified change during 2000–2021 in these metrics and highlighted insights gained from the complementary sub-indicators of forest quality relative to the official sub-indicators based on forest extent,Forests covered about 60–70% of the forested ecoregions in each country in 2000 and this proportion declined in all three countries by approximately 4% by 2021. Only a subset of the forested area was of high forest quality. Natural forests represented about 40% of forests in Colombian and Ecuador in 2000 and 50% in Peru. Those proportions declined: by 6.3% in Colombia, 6.5% in Ecuador, and 3.4% in Peru. Even less of the forested area was Core Forest in 2013; less than 28% among countries. During 2013–2021, the proportion of forest that was Core decreased by 2.3% in Colombia, 4.5% in Ecuador, and 6.7% in Peru. Connected Forests were about 17–22% of forests among the countries in 2013 and declined 10.4% in Colombia, 1.6% in Ecuador, and 3.8% in Peru by 2021. Forests high in forest structure were 10–18% of forests in 2012 among the countries and increased by 1.1–2% by 2021. Forests of high integrity were 7–13% of forests in 2012 and increased by1.4–2% by 2021. Riparian forests represented less than about 7–9% among the countries and declined by 0.6–1.3% by 2021. Thus, the area of highly quality forest across the countries was substantially less than full forest extent and high-quality forest declined at a higher rate than forest extent during 2000–2021. Forest structure and integrity did increase slightly over this time period.Our results for trends in forest naturalness, riparian association, within stand structure, fragmentation, and connectivity demonstrate how consideration of forest quality provides a much stronger basis for evaluating success in meeting SDG15 targets than consideration of forest extent alone.

Abstract Recently, several studies have investigated the neurodevelopment of psychiatric disorders using brain data acquired via structural magnetic resonance imaging (sMRI). These analyses have shown the potential of sMRI data to provide a relatively precise characterization of brain structural biomarkers. Despite these advances, a relatively unexplored question is how reliable and consistent a model is when assessing subjects from other independent datasets. In this study, we investigate the performance and generalizability of the same model architecture trained from distinct datasets comprising youths in diverse stages of neurodevelopment and with different mental health conditions. We employed models with the same 3D convolutional neural network (CNN) architecture to assess autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), brain age, and a measure of dimensional psychopathology, the Child Behavior Checklist (CBCL) total score. The investigated datasets include the Autism Brain Imaging Data Exchange II (ABIDE-II, N = 580), Attention Deficit Hyperactivity Disorder (ADHD-200, N = 922), Brazilian High-Risk Cohort Study (BHRCS, N = 737), and Adolescent Brain Cognitive Development (ABCD, N = 11,031). Models’ performance and interpretability were assessed within each dataset (for diagnosis tasks) and inter-datasets (for age estimation). Despite the demographic and phenotypic differences of the subjects, all models presented significant estimations for age (p value

ABSTRACT Multiple respiratory viruses, including influenza A virus (IAV), can be transmitted via expiratory aerosol particles, and aerosol pH was recently identified as a major factor influencing airborne virus infectivity. Indoors, small exhaled aerosols undergo rapid acidification to pH ~4. IAV is known to be sensitive to mildly acidic conditions encountered within host endosomes; however, it is unknown whether the same mechanisms could mediate viral inactivation within the more acidic aerosol micro-environment. Here, we identified that transient exposure to pH 4 caused IAV inactivation by a two-stage process, with an initial sharp decline in infectious titers mainly attributed to premature attainment of the post-fusion conformation of viral protein haemagglutinin (HA). Protein changes were observed by hydrogen-deuterium exchange coupled to mass spectrometry (HDX-MS) as early as 10 s post-exposure to acidic conditions. Our HDX-MS data are in agreement with other more labor-intensive structural analysis techniques, such as X-ray crystallography, highlighting the ease and usefulness of whole-virus HDX-MS for multiplexed protein analyses, even within enveloped viruses such as IAV. Additionally, virion integrity was partially but irreversibly affected by acidic conditions, with a progressive unfolding of the internal matrix protein 1 (M1) that aligned with a more gradual decline in viral infectivity with time. In contrast, no acid-mediated changes to the genome or lipid envelope were detected. Improved understanding of respiratory virus fate within exhaled aerosols constitutes a global public health priority, and information gained here could aid the development of novel strategies to control the airborne persistence of seasonal and/or pandemic influenza in the future. IMPORTANCE It is well established that COVID-19, influenza, and many other respiratory diseases can be transmitted by the inhalation of aerosolized viruses. Many studies have shown that the survival time of these airborne viruses is limited, but it remains an open question as to what drives their infectivity loss. Here, we address this question for influenza A virus by investigating structural protein changes incurred by the virus under conditions relevant to respiratory aerosol particles. From prior work, we know that expelled aerosols can become highly acidic due to equilibration with indoor room air, and our results indicate that two viral proteins are affected by these acidic conditions at multiple sites, leading to virus inactivation. Our findings suggest that the development of air treatments to quicken the speed of aerosol acidification would be a major strategy to control infectious bioburdens in the air.