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Assessing random forest performance in low resource speech emotion recognition
Fully Fused Hydrazine-Embedded Nanographene with Near-Infrared Chiroptical Emission
Early sarcopterygian morphological disparity through the Devonian-Carboniferous crisis
Abstract Major morphological adaptations characterized the early evolutionary history of sarcopterygians during the Devonian (419–359 Ma) and the Carboniferous (359–299 Ma), punctuated by environmental changes and biodiversity crises. Here we present geometric morphometrics analyses of early sarcopterygian morphology to explore the impact of environmental and phylogenetic constraints on their morphology. Three analyses were performed by digitizing 2D landmarks and semi-landmarks on palaeontological reconstructions of the body shape, cheek, and skull roof. Major changes in shape seem associated with geological and biological changes from the Late Devonian and Early Carboniferous (Mississippian). An increase in shape diversity occurred during the Middle Devonian, when the first forests appeared, influencing freshwater and transitional environments, and when reef ecosystems were the most diversified. Skull roof and cheek disparity decrease during the end-Devonian mass extinction and recover during the Mid-Late Mississippian, with the reemergence of metazoan reefs and the rise of surviving groups such as actinistians. The skull roof disparity is associated primarily with shared ancestry and appears to be largely driven by the lack of an intracranial joint in dipnoans and tetrapods. The Devonian to Carboniferous environmental changes constitute a major turning point in early sarcopterygian history by having deeply impacted their morphological disparity.
Stereoselective Synthesis of Polyketide Motifs via Nickel-Catalyzed Multicomponent Coupling of Aldehydes, Dienes, and Boronic Acids: Reaction Development and Mechanistic Insights
Immune profiling identifies the contribution of extracellular vesicles to immune modulation and progression in prostate cancer
Structural Heterogeneity of the Membrane-Interacting Region of the HIV-1 Envelope Glycoprotein
Boron adsorption from aqueous solutions using chemically activated kaolin clay adsorbents kinetics isotherm and thermodynamic studies
Role of Surface Hydroxyls in Atomic-Scale Copper Restructuring during CO Electroreduction
Analysis of physical mechanisms for channel-length-dependent PBTS reliability in SA TG coplanar IGZO TFTs
Abstract This study investigates the physical mechanisms for channel-length-dependent positive bias temperature stress (PBTS) reliability in self-aligned top-gate (SA TG) coplanar indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs). We fabricated devices with channel lengths of 3 µm, 12 µm, and 20 µm and characterized them using high-low frequency capacitance-voltage measurements and low-frequency noise analysis. Experimental results show that the 3 µm channel length device exhibits a significantly lower subgap density of states in the IGZO channel and a reduced near-interface trap density in the gate dielectric compared to its longer-channel counterparts. These reductions are strongly correlated with the enhanced PBTS reliability of the short-channel SA TG coplanar IGZO TFTs. We propose that hydrogen diffusion from the n + -IGZO source/drain extensions during fabrication may be the underlying mechanism, leading to defect passivation in both the IGZO channel and the SiO 2 gate dielectric. These findings offer physical insights into the degradation behavior of IGZO TFTs and provide practical guidance for designing highly reliable backplane transistors for advanced active-matrix organic light-emitting diode displays.
Nitrite as a Synthon for Nitroxyl (HNO): Mechanistic Insights and Chemical Evidences of Transient Intermediates
Evaluating experimental design to sample mosquitoes
The Interplay of Vibrational Coherence and Photoinduced Ultrafast Chemical Reactions
Modeling unobserved heterogeneity in multistate event history data using frailty and weighted survival approaches
Abstract Conventional survival analysis models typically assume that the hazard function depends solely on the baseline hazard and covariate values, overlooking unobserved factors that influence survival outcomes. In practice, however, unmeasured variables often contribute to heterogeneity among seemingly similar individuals. Frailty models offer an effective approach to account for such unobserved heterogeneity, providing a robust framework for analyzing naturally clustered survival data. This study applies frailty models to multistate event history data, emphasizing their ability to handle unobserved heterogeneity. We introduce individual-specific survival weights to adjust survival times, better reflecting the impact of unmeasured factors. These weighted survival times are critical when data exhibit bias or when standard models fail to fully capture the influence of investigated variables. Through a simulation study, we evaluate the effectiveness and performance of frailty models in a multistate framework, comparing mean, mean squared error (MSE), and bias of regression coefficients with and without frailty. For example, in the simulated dataset for age bias has reduced from -0.01 in unweighted survival time to -0.03 in weighted survival time for transition $$\tau _{12}$$ , similarly for $$\tau _{23}$$ bias has reduced from 0.01 to -0.05. Our findings underscore the importance of addressing unobserved heterogeneity in survival analysis, particularly in multistate models with weighted survival times.
Entropy-Driven Amino Acid-Based Coacervates with Enzyme-Free Metabolism and Prebiotic Robustness
Structural and biological characterization of carbon–graphene biomaterials derived from black liquor with functional properties for bone tissue engineering
Abstract Carbon-based biomaterials are promising for the field of tissue bioengineering due to their biocompatibility, high porosity, and physicochemical properties that allow functionalization and combination with other materials. In this study, carbon derived from black liquor was used to develop bone grafts. This carbon matrix (CA) was associated with nanomaterials—graphene, graphene oxide, and nano-graphite (CAG, CAGO, and CANG, respectively)—for potential applications in the repair of orofacial malformations. The scaffolds were evaluated for biocompatibility and their effect on cell viability using mesenchymal stem cells, followed by implantation in 16 male Wistar rats with non-critical bone defects in both tibias. Histological analysis demonstrated that all scaffolds were biocompatible, with defects showing repair, osteoprogenitor cell presence, and vascular channel formation. Histomorphometric assessment of bone neoformation revealed the highest repair potential in the CAG group (89% at 30 days), while the other groups showed similar bone formation: CA = 72%, CAGO = 69%, and CANG = 80%. All scaffolds promoted bone tissue formation, with the carbon-graphene scaffold yielding the greatest percentage of new bone.
Enantioselective Trifunctionalization of Terminal Alkynes
Integrating fiber-optic seismic arrays into earthquake early warning systems with the dEPIC framework
Abstract Distributed Acoustic Sensing (DAS) can enhance earthquake early warning (EEW) by transforming existing fiber-optic cables into dense seismic arrays, including in offshore areas with sparse instrumentation. We present dEPIC (DAS–Earthquake Point-source Integrated Code), the first operational DAS-integrated EEW framework, deployed on a submarine cable in Monterey Bay, California, and designed to operate independently or jointly with ShakeAlert’s EPIC algorithm. dEPIC combines GPU-accelerated machine-learning phase picking, grid-search location, and empirical magnitude estimation, with real-time quality metrics to suppress unstable solutions. In event replays and continuous data tests, dEPIC detected both onshore and offshore earthquakes accurately with sub-second processing time. The modular, edge-computing design enables adaptation to future DAS deployments to improve existing EEW systems like ShakeAlert.