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Commensurate, Incommensurate, and Reconstructed Structures of Multilayer Transition Metal Dichalcogenide and Their Applications
No full textMultilayer transition metal dichalcogenides (ML-TMDs) with commensurate, incommensurate, and reconstructed structures, have emerged as a class of 2D materials with unique properties that differ significantly from their monolayer counterparts. While previous research has focused on monolayers, the discovery of various novel properties has sparked interest in multilayers with diverse structures engineered through stacking. These materials are characterized by interactions between layers and exhibit remarkable tunability in their structural, optical, and electronic behaviors depending on stacking order, twist angle, and interlayer coupling. This review provides an overview of ML-TMDs and explores their properties such as electronic band structure, optical responses, ferroelectricity, and anomalous Hall effect. Various synthetic methods employed to fabricate ML-TMDs, including mechanical stacking and chemical vapor deposition techniques, with an emphasis on achieving precise control of the twist angles and layer configurations, are discussed. This study further explores potential applications of ML-TMDs in nanoelectronics, optoelectronics, and quantum devices, where their unique properties can be harnessed for next-generation technologies. The critical role played by these materials in the development of future electronic and quantum devices is highlighted.N
Advancements in Chemical Vapor Deposited Carbon Films for Secondary Battery Applications
No full textCarbon films, synthesized via chemical vapor deposition (CVD), have gained significant attention in secondary battery applications, where stability and capacity are required to be improved for next-generation electronic devices and electric vehicles. Beyond the inherent properties of carbon films, such as high electrical conductivity, mechanical strength, chemical stability, and flexibility, the CVD method provides a high degree of freedom in designing the carbon films in battery applications, enabling conformal coating with structure engineering for modification of its electrical and mechanical properties. In this review, the CVD-grown carbon films are highlighted in the secondary battery applications, enabling them to overcome critical issues, such as volume expansion, sluggish kinetics, and unstable interfaces. To deeply understand the CVD-grown carbon films, such as graphene and amorphous carbon, a comprehensive overview of the CVD process is also provided, focusing on growth mechanisms, control of 3D morphology, and doping techniques. In addition, a broad range of applications are introduced for carbon films in battery components, including their use in cathodes, anodes, and current collectors, as well as their potential in advanced battery systems, such as lithium-sulfur and all-solid-state batteries. This review proposes future directions for optimizing carbon films to achieve practical applications in next-generation energy storage devices.N
Programmable photonic unitary circuits for light computing
No full textUnitarity serves as a fundamental concept for characterizing linear and conservative wave phenomena in both classical and quantum systems. Developing platforms that perform unitary operations on light waves in a universal and programmable manner enables the emulation of complex light-matter interactions and the execution of general-purpose functionalities for wave manipulations, photonic computing, and quantum circuits. Recently, numerous approaches to implementing programmable photonic unitary circuits have been proposed and demonstrated, each employing different design strategies that distinctly impact overall device performance. Here, we review foundational design principles and recent achievements in the implementation of programmable photonic unitary circuits, with a particular focus on integrated photonic platforms. We classify the design strategies based on the dimensionality of nontrivial unit operations in their building blocks: lower-dimensional unitary units, such as SU(2) operations, and higher-dimensional ones, such as Fourier transforms. In each category, recent efforts to leverage alternative physical axes, such as the temporal and frequency domains, to address scalability challenges are also reviewed. We discuss the underlying concepts, design procedures, and trade-offs of each design strategy, especially in relation to light-based computing.Y
Longitudinal changes in ocular biometry and their effect on intraocular lens power calculation accuracy in cataract patients
No full textPurpose To investigate the changes in ocular biometry over time and their impact on intraocular lens (IOL) calculation in adult Korean patients with cataracts. Methods Inclusion criteria were patients who underwent two consecutive ocular biometric measurements spaced more than one year apart using the IOLMaster 700 between November 2019 and February 2024 at a tertiary hospital in Seoul, Korea. Longitudinal changes in ocular biometry were evaluated. Predictive errors were compared among patients who underwent cataract surgery using the SRK/T, Kane, Barrett Universal II, Cook K6, EVO, Hill-RBF, Hoffer QST, and Pearl DGS formulas. Results A total of 448 eyes from 448 patients were included. Ocular biometry measured over an average interval of 23.4 months showed that with increasing age, axial length elongated (0.04 +/- 0.10 mm, p < 0.001), and the magnitude of total corneal astigmatism increased (0.04 +/- 0.39 D, p = 0.018). The mean absolute predictive errors of the final measurements were significantly smaller compared to the initial measurements in the Barrett Universal II, EVO, Kane, and Pearl DGS formulas (difference of -0.05 D, -0.05 D, -0.06 D, and - 0.05 D, respectively). In the subgroup of eyes with an axial length of 25 mm or longer, the final measurements showed even greater reduction in mean absolute predictive errors across multiple formulas, including Barrett Universal II, Cook K6, EVO, Hill-RBF, Hoffer QST, Kane, and Pearl DGS, with reductions of -0.11 D, -0.11 D, -0.10 D, -0.08 D, -0.10 D, -0.09 D and - 0.10 D, respectively. Conclusions Axial length increases and corneal curvature changes with aging. IOLMaster 700 ocular biometry results measured closer to the date of surgery were more accurate in IOL power calculation than those measured more than one year earlier, with the greatest improvement observed in myopic eyes. Therefore, it is recommended to repeat IOLMaster 700 biometry before surgery if the previous measurements were taken more than a year ago.Y
Mechanistic Insights into the Role of Elements in Ni-Co-P Catalysts for Electrochemical Conversion of 5-Hydroxymethylfurfural to 2,5-Furandicarboxylic Acid
No full textNi phosphides and NiCo alloys are extensively explored for their remarkable efficiency in biomass alcohol oxidations, yet the underlying mechanisms remain inadequately understood. This study thoroughly elucidates the roles of Ni, Co, and P in improving the catalytic performance of Ni-Co-P catalysts for the electrochemical conversion of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a promising biomass-derived building block replacing terephthalic acid. Phosphorization of Ni results in the partial formation of Ni2P phase and significantly boosts the formation of the reactive NiOOH phase on the surface, which is the crucial catalytic phase for converting HMF into FDCA. The integration of Co into the heterojunction between Ni2P and NiOOH enhances the oxidation reactivity of 5-formyl-2-furancarboxylic acid (FFCA), a pivotal intermediate influencing FDCA productivity, by selectively stabilizing aldehydes, thereby promoting further oxidation rather than surface desorption. in situ/operando spectroscopic analyses consistently highlight the equal significance of the rapid generation of NiOOH and the robust adsorption of reactant molecules at the surface in achieving high catalytic performance. These insights into elemental contributions set a new standard for designing multi-component electrocatalysts for efficient biomass alcohol oxidation.Y
Strategic Thinking Skills: A Key to Collective Economic Success
No full textWe conduct a large-scale experiment to measure elementary aspects of strategic thinking skills and their linkage to labor market outcomes. Two incentivized measures of higher-order rationality and backward induction are developed. Males' (females') strategic thinking skills are positively (negatively) associated with individual labor income. However, among married individuals, strategic thinking skills are significantly and positively associated with their household labor income regardless of gender, highlighting the importance of strategic thinking skills for collective economic success. We argue that the intrahousehold channels encompassing collective labor supply with home-to-workplace spillover and marriage assortative matching offer the most plausible explanation for our findings.N
Dual Activation of Organoboron for the Ion-Pair-Mediated Synthesis of Hindered Alkyl Fluorides
No full textA novel electrochemical approach for the synthesis of hindered alkyl fluorides has been developed. The protocol grants access to a diverse array of tertiary and secondary alkyl fluorides using readily attainable organoboron precursors under mild conditions. The efficiency of the system stems from the dual activation of the redox-active borate intermediate, providing both electrophilic and nucleophilic reaction partners in the form of an internally generated ion pair.N
Effect of Individual Agents on Time to Culture Conversion in Mycobacterium avium Complex Pulmonary Disease
No full textIn a cohort of 534 patients treated for Mycobacterium avium complex pulmonary disease, those who failed to achieve culture conversion were older, had higher proportions of males and cavity presence, were more likely to receive clofazimine and aminoglycosides, but less likely to receive rifampicin, and had a shorter overall treatment duration. Time-varying analysis of individual drug effects on time to culture conversion identified rifampicin as being associated with a reduced culture conversion rate (adjusted hazard ratio, 0.959; 95% confidence interval, .924-.995; P = .027), suggesting a potentially negative effect on Mycobacterium avium complex pulmonary disease outcomes, whereas other drugs showed no significant association.Y
Correlation between newly formed bone and the progression of experimental peri-implantitis with or without alveolar ridge preservation in infected and non-infected teeth: a secondary analysis of a preclinical study
No full textPurpose We examined the progression of experimental peri-implantitis in sites that underwent either alveolar ridge preservation (ARP) or spontaneous healing (SH), comparing infected teeth (IT) and non-infected teeth (NIT). This investigation is a secondary analysis of a preclinical study aimed at exploring the correlation between newly formed bone and implant stability quotient (ISQ), as well as the association between newly formed bone and the progression of experimental peri-implantitis. Methods The bilateral mandibular third or fourth premolars of 6 beagle dogs were randomly assigned to 4 groups: IT/SH, IT/ARP, NIT/SH, and NIT/ARP. Following implant placement, core biopsies were retrieved from each site, and the ISQ value was measured. A 3-month period was allowed for peri-implantitis induction, followed by an additional 3 months for the spontaneous progression of peri-implantitis, with radiographs taken at each time point. Results During the spontaneous progression of peri-implantitis, no statistically significant differences were observed among the groups in terms of mean ISQ values and radiographic marginal bone loss. Similarly, the percentages of bone substitute, newly formed bone, and fibrovascular connective tissue in core biopsies did not differ significantly among the groups. Linear regression analysis revealed no significant linear correlation between newly formed bone and ISQ in any group (P>0.05). However, a weak linear correlation between newly formed bone and marginal bone loss during the spontaneous progression of peri-implantitis was noted in the IT/SH group alone (P=0.036). Conclusions Within the limitations of this study, we were unable to demonstrate that ARP could improve newly formed bone or primary implant stability. Furthermore, neither ARP nor SH significantly influenced the spontaneous progression of experimental peri-implantitis.N
Bayesian Model Calibration and Sensitivity Analysis for Oscillating Biological Experiments
No full textUnderstanding the oscillating behaviors that govern organisms' internal biological processes requires interdisciplinary efforts combining both biological and computer experiments, as the latter can complement the former by simulating perturbed conditions with higher resolution. Harmonizing the two types of experiment, however, poses significant statistical challenges due to identifiability issues, numerical instability, and ill behavior in high dimension. This article devises a new Bayesian calibration framework for oscillating biochemical models. The proposed Bayesian model is estimated relying on an advanced Markov chain Monte Carlo (MCMC) technique which can efficiently infer the parameter values that match the simulated and observed oscillatory processes. Also proposed is an approach to sensitivity analysis based on the intervention posterior. This approach measures the influence of individual parameters on the target process by using the obtained MCMC samples as a computational tool. The proposed framework is illustrated with circadian oscillations observed in a filamentous fungus, Neurospora crassa.Y