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Atomically Dispersed High-Valent d<SUP>0</SUP>-Metal Breaks the Activity-Stability Trade-Off in Proton Exchange Membrane Water Electrolysis
No full textGreen hydrogen production via proton exchange membrane water electrolysis (PEMWE) faces economic feasibility challenges, primarily due to its reliance on noble metal catalysts. While cost-effective Ru-based catalysts show promise as alternatives to expensive Ir-based catalysts for an anodic oxygen evolution reaction, their long-term performance is compromised by overoxidation at high current densities. In addressing this challenge, we present a cooperative dual-site strategy for atomic-scale incorporation of high-valent d0-metal cations into RuO2. This synthesis results in uniformly distributed Ru-O-d0metal bonds, effectively reconciling the activity and stability trade-off. Leveraging these effects, our optimized Ta1/RuO2 catalyst demonstrates exceptional performance, with a low overpotential of 164 +/- 2 mV and stable operation for 1000 h at 100 mA cm-2. In practical PEMWE systems, Ta1/RuO2 achieves 1.58 V at 2 A cm-2, surpassing the 2026 Department of Energy target, and maintains remarkable stability over 650 h at 500 mA cm-2. This breakthrough offers a highly active and durable PEMWE system suitable for industrial-scale applications.N
MultiCook: A Tool That Improves Accuracy of HLA Imputation by Combining Probabilities From Multiple Reference Panels and Methods
No full textHLA molecules are produced by genes within the Major Histocompatibility Complex (MHC). Although the identification of HLA genotype is costly, fortunately, recent computational methods have made it possible to impute HLA genotypes using inexpensive single nucleotide polymorphism (SNP) markers. These imputation methods perform well if ethnicity-matched reference panels are provided. However, the availability of large-sized panels specific to each ethnicity remains limited. As a result, to achieve better imputation for each population, we need to utilise available multiple reference panels together. In this study, we introduce MultiCook, which enables users to simultaneously utilise existing multiple HLA imputation methods with multiple reference panels. MultiCook is versatile in that panels typed with different SNP genotyping platforms can seamlessly be merged, outputs from multiple imputation methods can be combined and the output from the Michigan imputation server with a multiethnic reference panel can also be incorporated. We compared MultiCook to the existing single-reference-panel approaches and the Michigan HLA imputation server. In evaluation with a cohort of 413 Koreans, MultiCook reduced the imputation error rate by about one third, from 4.70% to 3.31%, by combining 1KG EAS (N = 504) and HAN Chinese (N = 9773) reference panels compared to the single-panel approach. Moreover, MultiCook achieved better accuracy for imputing low-frequency alleles in evaluation benchmarks.Y
Reliable Oscillatory Neural Network Utilizing a Thermally Stable Single Transistor-based Oscillator
No full textA reliable oscillatory neural network (ONN) is demonstrated using a thermally stable single transistorbased oscillator (1T-oscillator). Instead of relying on thermally sensitive impact ionization (I.I.), thermally insensitive band-to-band tunneling (BTBT) is utilized to trigger a single-transistor latch (STL), ensuring stable oscillation characteristics. The study investigates the properties of coupled oscillators, the fundamental elements of ONN, across different temperature settings to confirm thermal stability effects. Additionally, the reliability of ONN is verified through a vertex coloring task, a representative problem in nondeterministic polynomial time hard (NP-hard) combinatorial optimization.N
Atomic lift-off of epitaxial membranes for cooling-free infrared detection
No full textRecent breakthroughs in ultrathin, single-crystalline, freestanding complex oxide systems have sparked industry interest in their potential for next-generation commercial devices1,2. However, the mass production of these ultrathin complex oxide membranes has been hindered by the challenging requirement of inserting an artificial release layer between the epilayers and substrates3,4. Here we introduce a technique that achieves atomic precision lift-off of ultrathin membranes without artificial release layers to facilitate the high-throughput production of scalable, ultrathin, freestanding perovskite systems. Leveraging both theoretical insights and empirical evidence, we have identified the pivotal role of lead in weakening the interface. This insight has led to the creation of a universal exfoliation strategy that enables the production of diverse ultrathin perovskite membranes less than 10 nm. Our pyroelectric membranes demonstrate a record-high pyroelectric coefficient of 1.76 x 10-2 C m-2 K-1, attributed to their exceptionally low thickness and freestanding nature. Moreover, this method offers an approach to manufacturing cooling-free detectors that can cover the full far-infrared spectrum, marking a notable advancement in detector technology5.N
Creditor control rights and executive bonus plans
No full textWe study the extent to which creditors shape the executive bonus plans of their financially distressed borrowers. Financial distress can exacerbate agency conflicts between creditors and borrowers as concerns with underinvestment become more acute due to managerial myopia and debt overhang. Consequently, we expect creditors to exert their influence to ensure that these managers' incentive-compensation plans encourage longer-term investments and directly reward outcomes that benefit creditors without exposing managers to unnecessary risk. We argue that bonus plans are an especially important way to provide these incentives because their flexibility allows creditors to more precisely target specific investment objectives. We find that borrowers' bonus plans tend to have longer horizons and more convex payouts following covenant violations, especially when bonus plans can be a particularly effective way to address distress-related agency conflicts. Our evidence suggests that creditors protect their interests by exercising their control rights to shape their borrowers' incentive-compensation plans.Y
Integrating text parsing and object detection for automated monitoring of finishing works in construction projects
No full textConstruction process monitoring traditionally relies on manual inspections and document cross-referencing, leading to inefficiencies in project management. Despite advances enabling computer vision-based monitoring and automated document analysis, integrating these technologies remains challenging, particularly in connecting field data with work documentation. This paper proposes an automated monitoring system integrating computer vision-based field data with text-based work instructions. The system employs YOLOv5 object detection models to analyze construction site images and architectural drawings, while utilizing text parsing techniques to extract information from work instructions. Validation using thirty apartment units demonstrated effectiveness in monitoring finishing works, particularly masonry and tiling applications. Results showed consistent performance in establishing automated connections between work instructions, drawings, and site conditions, reducing manual verification requirements while maintaining high accuracy. The successful implementation in finishing works demonstrates potential scalability for broader construction applications with varying complexity levels.N
Obstetric and neonatal outcomes of extremely obese pregnant women after late preterm gestation
No full textObjective To determine the obstetric and neonatal outcomes of pregnant women with extreme obesity at birth after late preterm gestation. Methods This was a retrospective study on extremely obese pregnant women with body mass index (BMI) >= 40.0 kg/m(2) (obesity stage III according to the BMI classification of the World Health Organization) who had delivered at Seoul National University Bundang Hospital between September 2003 and February 2023. Fetal death in utero and preterm births before 34 weeks of gestation were excluded. Obstetric and neonatal outcomes were reviewed. Results A total of 94 extremely obese pregnant women were included and the median value of BMI at delivery was 42.4 kg/m(2). When analyzed according to the obesity II category of pre-pregnancy BMI, the rate of chronic hypertension was higher in the alleged extreme obese women than those with lower pre-pregnancy BMI (34% vs. 10%, p = 0.012). However, preterm labor with tocolytics was higher in the group with lower BMI than 35.0 kg/m(2) (26% vs. 5%, p = 0.007). The proportion of adverse neonatal outcomes such as neonatal intensive care unit admission, the use of respiratory support (including positive pressure ventilation, continuous positive airway pressure, and mechanical ventilator), and jaundice were higher in the group with pre-pregnancy BMI < 35.0 kg/m(2) than that with BMI >= 35.0 kg/m(2) group (all p-value < 0.05). The use of neonatal respiratory support increased as the category of pre-pregnancy BMI was lower and as the degree of weight gain during pregnancy was higher. Conclusions In extremely obese women (stage III) at delivery in late preterm gestation, the obstetric outcomes such as use of tocolytics for preterm labor and adverse neonatal respiratory outcomes seemed to be higher for the women who were not that much obese before pregnancy than those who were already extremely obese. Therefore, weight gain during pregnancy needs to be closely monitored for pregnant women especially when obese.Y
The Average Stellar Population Age and Metallicity of Intermediate-redshift Quiescent Galaxies
No full textThe HectoMAP spectroscopic survey provides a unique mass-limited sample of more than 35,000 quiescent galaxies (D(n)4000 > 1.5) covering the redshift range 0.2 < z < 0.6. We segregate galaxies in bins of properties based on stellar mass, D(n)4000, and redshift to construct a set of high signal-to-noise spectra representing a massive (M-* > 10(10)M(circle dot)) quiescent population at intermediate redshift. These high-quality summed spectra enable full spectrum fitting and the related extraction of the average stellar population age and metallicity. The average galaxy age increases with the central D(n)4000 as expected. The correlation is essentially invariant with stellar mass; thus, D(n)4000 is a robust proxy for quiescent galaxy stellar population age. HectoMAP provides the first quiescent sample at intermediate redshift comparable with z similar to 0 mass-complete data sets. Scaling relations derived from the HectoMAP summed spectra connect stellar age and metallicity with quiescent galaxy stellar mass up to z similar to 0.5. Anticorrelation between the equivalent width (EW) of the [O ii] emission line and stellar age, together with the mild increase in stellar age with stellar mass, supports a broad range of timescales for the mass assembly of intermediate-redshift quiescent systems. On average, the most massive galaxies (M-* > 10(11)M(circle dot)) assemble the bulk of their stars at earlier epochs. A strong increase in the average stellar metallicity with stellar mass, along with the correlation between the [O ii] EW and metallicity at 0.2 < z < 0.4, suggests that lower mass galaxies are more likely to have experienced recent star formation episodes; related feedback from massive stars affects the chemical enrichment of these galaxies.Y
Genome-wide statistical evidence elucidates candidate factors of life expectancy in dogs
No full textIt is well-established that large and heavy dogs tend to live shorter lives. In this study, we aimed to determine whether traits other than body size are associated with the life expectancy of dogs. We compiled a dataset of 20 phenotypes, including body size, lifespan, snout ratio, and shedding, into a single matrix for 149 dog breeds using data from the American Kennel Club and other peer-reviewed sources. The analysis revealed that drooling might be associated with both the lifespan and body mass index of dogs. Furthermore, a genome-wide association study with adjusted phenotypes and statistical verification methods, such as Mendelian randomization. Additionally, conducting differential gene expression analysis with the salivary gland for the 2 cases, hypersalivation/less drooling vs various body sizes, we could observe the hypersalivation-related proteins. This genetic analysis suggests that body size and drooling might be candidate factors influencing lifespan. Consequently, we identified several candidate genes, including IGSF1, PACSIN2, PIK3R1, and MCCC2, as potential genetic factors influencing longevity-related phenotypes.Y