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Abstract Transition metal chalcogenides have been identified as low-cost and efficient electrocatalysts to promote the hydrogen evolution reaction in alkaline media. However, the identification of active sites and the underlying catalytic mechanism remain elusive. In this work, we employ operando X-ray absorption spectroscopy and near-ambient pressure X-ray photoelectron spectroscopy to elucidate that NiS undergoes an in-situ phase transition to an intimately mixed phase of Ni3S2 and NiO, generating highly active synergistic dual sites at the Ni3S2/NiO interface. The interfacial Ni is the active site for water dissociation and OH* adsorption while the interfacial S acts as the active site for H* adsorption and H2 evolution. Accordingly, the in-situ formation of Ni3S2/NiO interfaces enables NiS electrocatalysts to achieve an overpotential of only 95 ± 8 mV at a current density of 10 mA cm−2. Our work highlighted that the chemistry of transition metal chalcogenides is highly dynamic, and a careful control of the working conditions may lead to the in-situ formation of catalytic species that boost their catalytic performance.

– This study investigates the effect of managerial ability on labor productivity by analyzing various methods in the firm-year panel data of listed firms in South Korea from 2002 to 2019. Managerial ability was analyzed using the measurement method of Demerjian et al. (2012), while labor productivity was analyzed using value-added and sales. The authors find that managerial ability has a positive effect on labor productivity. In other words, the productivity of employees improves with the appointment of a manager with higher abilities. The study’s findings suggest that firms should consider managerial ability as a means of improving labor productivity.

Void slabs offer a promising solution for sustainable construction due to their reduced weight and potential for recycled materials. However, their inherent hollowness can compromise shear capacity compared to solid slabs. This study investigates the effectiveness of shear reinforcement in mitigating this vulnerability. Experimental testing with a four-point support loading confirmed shear failure in all specimens and revealed a significant reserve of shear strength exceeding predictions from ACI 318-14 by at least 1.436. This suggests the potential for more efficient designs that utilize less shear reinforcement while maintaining structural integrity. An inverse relationship between porosity and shear strength was observed, highlighting the importance of considering void content during design. Among established design codes (ACI 318-14, UBC 2, and CEB-FIP 1990), CEB-FIP 1990 provided the most accurate prediction of shear capacity for these reinforced hollow slabs. These findings offer valuable insights for optimizing the shear design of voided slabs. The observed strength reserve suggests the potential for reduced shear reinforcement while maintaining safety. Additionally, the influence of porosity and the code comparison provide crucial considerations for future design practices. This research paves the way for developing efficient and safe voided slab applications, promoting sustainability in the construction industry.

Abstract Characterizing the genetic diversity and population structure of breeding materials is essential for breeding to improve crop plants. The potato is an important non-cereal food crop worldwide, but breeding potatoes remains challenging owing to their auto-tetraploidy and highly heterozygous genome. We evaluated the genetic structure of a 110-line Korean potato germplasm using the SolCAP 8303 single nucleotide polymorphism (SNP) Infinium array and compared it with potato clones from other countries to understand the genetic landscape of cultivated potatoes. Following the tetraploid model, we conducted population structure analysis, revealing three subpopulations represented by two Korean potato groups and one separate foreign potato group within 110 lines. When analyzing 393 global potato clones, country/region-specific genetic patterns were revealed. The Korean potato clones exhibited higher heterozygosity than those from Japan, the United States, and other potato landraces. We also employed integrated extended haplotype homozygosity (iHS) and cross-population extended haplotype homozygosity (XP-EHH) to identify selection signatures spanning candidate genes associated with biotic and abiotic stress tolerance. Based on the informativeness of SNPs for dosage genotyping calls, 10 highly informative SNPs discriminating all 393 potatoes were identified. Our results could help understanding a potato breeding history that reflects regional adaptations and distinct market demands.

The ability to mix multiple elements in a structure is crucial for obtaining Cu‐based nanostructures and microstructures with desirable physicochemical properties. Precursors containing multiple metal cations, such as layered double hydroxides, have been used for the synthesis of multielement materials. However, these precursors experience difficulty containing large cations, which limits the functionalities of the derived materials. Herein, the development of Cu‐based hydroxy double salts (HDSs), versatile precursors that accommodate a broad range of metal cations with homogeneous distributions, is reported. Up to 25 different metal cations are mixed with Cu in an HDS single phase, individually and simultaneously. The HDSs further exhibit useful properties with respect to anion exchange, exfoliation, and phase transformation to metal oxides. During the metal oxide transformation process, the formed crystal structures are mainly dependent on the ionic radius of the secondary metal cations. To prove their utility as precursors, the metal oxides derived from the HDSs are tested and found that they exhibited high catalytic activities for CO oxidation. This study significantly expands the compositional and structural freedom of Cu‐based multi‐elemental materials.

While organic semiconductors may be useful in photoelectrochemical water-splitting materials, they show low stability in water. Here, the authors report high-performance and stable organic-semiconductor-based photoanodes passivated using nickel foils, GaIn eutectic, and layered double hydroxides.

Hydrogen peroxide (H2O2), the simplest peroxide consisting of only hydrogen and oxygen, is globally used as a green oxidant. It is also a promising fuel source, and it can be produced on large scales in centralized containers. H2O2 is mainly produced by the anthraquinone process, but it involves energy-consuming reactions and generates organic waste. As the demand for H2O2 continues to grow, alternative technologies that overcome these drawbacks are sought for its generation. The generation of H2O2 through the redox reaction of water and oxygen can be a low-cost, sustainable, and efficient production method. However, this reaction requires active and stable catalysts. In general, H2O2 can be generated by the oxidation of H2O at the anode of an electrochemical cell. Alternatively, H2O2 can also be formed by the reduction of O2 at the cathode. Despite the progress in the development and advancement of materials that catalyze these reactions, further research is required to increase the electron transport rates and active sites of the catalyst. In this article, we review the available catalytic materials for the electrochemical production of H2O2 and provide a summary and outlook of this field.

This study analyzed the firm’s actual case in an environment where the financial industry’s paradigm changes due to technological development. It focused on Deutsche Bank’s competitive action at the heart of the digitalizing European banking industry. This study presents the competitive dynamics among firms and the effects of such dynamics on firm performance. Based on the competitive dynamics between Deutsche Bank and other banks competing in the European banking industry, the Red Queen theory was applied. This study has shown that Deutsche Bank’s innovative actions in the digitalizing European banking industry are necessary and are a factor that can lead to successful firm performance in a hyper-competitive environment. Firms need to develop a capability to quickly capture the opportunities to innovate and take advantage of them to stay ahead of their competitors.

Metal oxide resistive switches rely on the migration of oxygen vacancies and electrons under applied voltage. Here, Cho et al. use nanocomposites to control the electronic and ionic conductivities in spatially distinct channels, and fabricate memristors with high on/off ratios and reproducibility.

Reinforced concrete is regarded as one of the ideal structural materials which comprises concrete with high compressive strength and reinforcing bars with high tensile strength. However, concrete has been pointed out that it consumes a large volume of energy and emits a lot of carbon dioxide during its manufacturing. In order to lower such environmental burdens of concrete structures, a number of studies and approaches have been carried out. The voided slab is also suggested as a new method to reduce the environmental burden since voided section of the slab would use less concrete compared with the normal reinforced concrete slab. However, no studies have evaluated the CO2 emissions and environmental performance of voided slabs. The purpose of this study was to evaluate the structural performance of voided slabs and empirically corroborate their environmental influence. The flexural performance test was carried out based on the variables of the depth of slab, types of the void former materials, and the hollowness ratio. In addition, comparison of the emission of CO2 was also performed by considering the hollowness ratio and types of void former materials over the normal reinforced concrete slab. The structural performance of the voided slab was similar or slightly higher than the normal reinforced concrete slab. The yield strength of specimens was increased approximately 10∼30% over the anticipated yield strength. Based on this result, it is considered that the voided slab would be sufficient to structural performance and beneficial to plane planning in buildings. In general, it is considered that the voided slab would be beneficial to both structural and environmental aspects. However, the test results in this research showed that the voided slab would emit more carbon dioxide emissions compared to the normal reinforced concrete slab. The main source of more CO2 emissions in the voided slab was the anchoring materials. In this research, wires were used to fix the void former materials to the reinforcing bars. In order for the voided slab to become a more eco-friendly and sustainable material, new anchoring methods such as use of recycled materials, new void former materials without anchoring, or other eco-friendly materials should be applied to reduce the emission of CO2.

Fusarium head blight (FHB), caused primarily by Fusarium graminearum, decreases grain yield and quality in wheat and barley. Disease severity, deoxynivalenol (DON), fungal biomass, and transcript accumulation were examined in a wheat near-isogenic line pair carrying either the resistant or susceptible allele for the chromosome 3BS FHB-resistance quantitative trait locus (Fhb1). Fhb1 restricts spread of disease symptoms but does not provide resistance to initial infection or initial DON accumulation. Wheat exhibits both induction and repression of large sets of gene transcripts during F. graminearum infection. In addition, a difference in the general timing of transcript accumulation in plants carrying either the resistant or susceptible allele at the Fhb1 locus was detected, and 14 wheat gene transcripts were detected that exhibited accumulation differences between the resistant and susceptible alleles. These results indicate that these may be host responses that differentiate the resistant from the susceptible interaction. Comparative analysis of the wheat–F. graminearum and the barley–F. graminearum interactions revealed a large set of conserved transcript accumulation patterns. However, we also detected gene transcripts that were repressed in wheat but not in barley. Based on the disease symptoms, transcript accumulation data, and comparative analysis of the barley and wheat host response to F. graminearum infection, we developed an integrated model for the interactions of wheat and barley with F. graminearum.

Fusarium head blight, caused primarily by Fusarium graminearum, is a major disease problem on barley (Hordeum vulgare L.). Trichothecene mycotoxins produced by the fungus during infection increase the aggressiveness of the fungus and promote infection in wheat (Triticum aestivum L.). Loss-of-function mutations in the TRI5 gene in F. graminearum result in the inability to synthesize trichothecenes and in reduced virulence on wheat. We examined the impact of pathogen-derived trichothecenes on virulence and the transcriptional differences in barley spikes infected with a trichothecene-producing wild-type strain and a loss-of-function tri5 trichothecene nonproducing mutant. Disease severity, fungal biomass, and floret necrosis and bleaching were reduced in spikes inoculated with the tri5 mutant strain compared with the wild-type strain, indicating that the inability to synthesize trichothecenes results in reduced virulence in barley. We detected 63 transcripts that were induced during trichothecene accumulation, including genes encoding putative trichothecene detoxification and transport proteins, ubiquitination-related proteins, programmed cell death-related proteins, transcription factors, and cytochrome P450s. We also detected 414 gene transcripts that were designated as basal defense response genes largely independent of trichothecene accumulation. Our results show that barley exhibits a specific response to trichothecene accumulation that can be separated from the basal defense response. We propose that barley responds to trichothecene accumulation by inducing at least two general responses. One response is the induction of genes encoding trichothecene detoxification and transport activities that may reduce the impact of trichothecenes. The other response is to induce genes encoding proteins associated with ubiquitination and cell death which may promote successful establishment of the disease.

Fusarium head blight (FHB) of barley (Hordeum vulgare L.) is caused by Fusarium graminearum. FHB causes yield losses and reduction in grain quality primarily due to the accumulation of trichothecene mycotoxins such as deoxynivalenol (DON). To develop an understanding of the barley-F. graminearum interaction, we examined the relationship among the infection process, DON concentration, and host transcript accumulation for 22,439 genes in spikes from the susceptible cv. Morex from 0 to 144 h after F. graminearum and water control inoculation. We detected 467 differentially accumulating barley gene transcripts in the F. graminearum-treated plants compared with the water control-treated plants. Functional annotation of the transcripts revealed a variety of infection-induced host genes encoding defense response proteins, oxidative burst-associated enzymes, and phenylpropanoid pathway enzymes. Of particular interest was the induction of transcripts encoding potential trichothecene catabolic enzymes and transporters, and the induction of the tryptophan biosynthetic and catabolic pathway enzymes. Our results define three stages of F. graminearum infection. An early stage, between 0 and 48 h after inoculation (hai), exhibited limited fungal development, low DON accumulation, and little change in the transcript accumulation status. An intermediate stage, between 48 and 96 hai, showed increased fungal development and active infection, higher DON accumulation, and increased transcript accumulation. A majority of the host gene transcripts were detected by 72 hai, suggesting that this is an important timepoint for the barley-F. graminearum interaction. A late stage also identified between 96 and 144 hai, exhibiting development of hyphal mats, high DON accumulation, and a reduction in the number of transcripts observed. Our study provides a baseline and hypothesis-generating dataset in barley during F. graminearum infection and in other grasses during pathogen infection.

Photoelectrochemical (PEC) water splitting to hydrogen is an attractive method for capturing and storing the solar energy in the form of chemical energy. Metal oxides are promising photoanode materials due to their low-cost synthetic routes and higher stability than other semiconductors. In this paper, we provide an overview of recent efforts to improve PEC efficiencies via applying a variety of fabrication strategies to metal oxide photoanodes including (i) size and morphology-control, (ii) metal oxide heterostructuring, (iii) dopant incorporation, (iv) attachments of quantum dots as sensitizer, (v) attachments of plasmonic metal nanoparticles, and (vi) co-catalyst coupling. Each strategy highlights the underlying principles and mechanisms for the performance enhancements.

An agricultural field is not always accessible for plant phenotyping with existing mobile platforms due to the limited space and regulated aviation area. Smartphone-triggered ground images were collected on a wheat field that has a limited access to monitor growth conditions of four wheat varieties: Shinyoung (SY), Joseong (JS), Taewoo (TW), and Cheongwoo (CW). For field mapping during the growing season, six sets of the raw images were acquired by a smartphone in an oblique view angle and processed to transform into nadir view images. Algorithms were developed to process the raw tile images for geometric rectification via row detection using Hough Transformation. Stitching software was developed to automate the high throughput image analytics of the skewed tile images into a stitched field image through deskewing, row alignment, overlap trimming, and resizing. Plot-level metrics were extracted to analyze plant growth of the wheat varieties using a gridding method for vegetation and leaf area indexes. The processed images resulted in the successful transformation and consistency of algorithms on image alignment and stitching. Plot-level analysis indicated that SY variety performed superior to the other varieties in both vegetation and leaf area indexes and was significantly different in the canopy coverage from the least performed TW variety. The image analytic methods developed in the study offer a flexible solution to stitch and align tile images by a hand-held camera in both oblique and nadir view via user-friendly interface software for high through plant phenotyping and can be adapted to other stationary or mobile imaging platforms in greenhouse and fields. [ABSTRACT FROM AUTHOR]

Understanding the mechanism of metal solidification holds both theoretical significance and practical importance. In this study, we conducted molecular dynamics simulations to investigate the impact of cooling rates on the solidification of a melted ruthenium alloy using the embedded atom method (EAM) potential. The EAM potential is a widely employed interatomic potential for describing the metallic system, which can capture numerous crucial properties, including mechanical properties, the energy of competing crystal structure dynamics, defects, and liquid structures. Our simulations showed that upon quenching with different cooling rates, the system transformed into a supercooled liquid state at 1200 K, and a hexagonal close-packed cluster emerged as a dominant structure that remained stable even in the supercooled state. A critical cooling rate (1011 K/s) marked the transition from crystal to amorphous phase; this transition exhibited an upward trend as the superheating temperature increased until it reached the maximum achievable cooling rate. Our simulations also revealed that the optimal conditions for undercooling and superheating occur at ∼0.4396 and 1.2893 Tm, respectively, where Tm is the melting temperature. Our results provide comprehensive insights into the evolution of melt structures with changing temperatures during deep undercooling, the formation of homogeneous melt-free crystal regions, and the effect of the molten state on solidification phenomena.

This study examines the crucial role of chief executive officers (CEOs) in post-acquisition integration, focusing on Chegg, a prominent ed-tech company in a rapidly evolving industry. Analyzing CEO actions post-acquisition through interviews and metrics, we find that a three-year CEO retention period significantly contributes to successful integration at Chegg. This research emphasizes the importance of understanding ideal CEO retention and their strategic actions, offering insights for more successful post-acquisition integration and long-term economic benefits.