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In this study, the impact of n -type organic electron acceptors incorporated in perovskite absorbers via antisolvent-assisted crystallization process is investigated on optical, electrical, and photovoltaic properties of perovskite solar cells (PSCs). The study examines the effect of three representative electron acceptors, including fullerene derivative (PC 61 BM), non-fullerene acceptor (ITIC), and fluorinated non-fullerene acceptor (ITIC-4F). The findings demonstrate that the inclusion of these electron acceptors stabilizes perovskite absorbers due to strong interaction between the organic acceptors and [PbI6]4- octahedra, leading to the successful passivation of defective antisites. Furthermore, ITIC-4F plays a crucial role in the tailored electronic structure of the perovskite absorber surface, facilitating efficient charge transport and suppressing carrier recombination in the device. The synergetic effect of defect passivation and electrical doping achieved by ITIC-4F resulted in an efficiency improvement of 17.31 % of MAPbI 3 -based PSCs under 1-Sun illumination, exceeding that of the pristine device (15.62 %) under the same conditions. The device passivated with ITIC-4F also delivered an efficiency of 20.00 % under dim-light irradiation conditions for indoor photovoltaic applications. The results highlight the potential of n -type organic semiconducting molecules as effective additives in the antisolvent-assisted crystallization of perovskite absorbers, offering valuable insights into the design of organic semiconducting additives for improving the film quality of perovskite absorbers and achieving high-performance PSCs. The findings provide a foundation for future research aimed at enhancing the optoelectronic properties and photovoltaic performance of PSCs. [Display omitted] • This study investigated n -type electron acceptors' role in dynamic doping of perovskite absorber layers. • Fluorinated non-fullerene acceptor showed multi-functional role in strong interaction for effective passivation and electrical doping. • Incorporation of fluorinated NFAs achieved 17.31 % and 20.00 % efficiency under 1-sun and dim-light conditions, respectively. [ABSTRACT FROM AUTHOR]

Insert parts in insert injection molding used to be deformed by pressure developed during the molding process. The plastic deformation of insert parts caused by injection pressure during insert injection molding for electric power plugs cannot be predicted by conventional injection molding analysis methods. In this study, the injection-structural coupled analysis was carried out to predict the plastic deformation of insert parts. Injection pressure developed during the molding process was calculated by the injection molding analysis software and was mapped onto the grid surface of the inner tube model for structural analysis as boundary conditions. The effect of process parameters such as injection time, melt temperature, and holding pressure on the injection pressure and the deformation of the inner tubes was examined to find the proper molding condition. The result from the analysis was compared to the insert injection molding experiment. Furthermore, the diameters of sub-runners in the multi-cavity mold of the power plugs were optimized to prevent the deformation of the inner tubes by the unbalanced filling of the melt into the linear arranged cavities using the injection-structural coupled analysis. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the friction and antiwear characteristics of nano-oil composed of refrigerant oil and fullerene nanoparticles in the sliding thrust bearing of scroll compressors. The nano-oil was evaluated using a sliding thrust bearing tester. The friction coefficient of fullerene nano-oil at the lower normal loads (<∼1200N) under the fixed orbiting speed (∼1800rpm) was ∼0.02, while that of pure oil was ∼0.03, indicating that the fullerene nanoparticles dispersed in the base refrigerant oil improved the lubrication property by coating the friction surfaces. However the difference between friction coefficients for both nano-oil and pure oil was found to be negligible at higher normal load conditions (>∼1200N), indicating that the nanoparticles in the base oil have little effect on the enhancement of lubrication between the friction surfaces. The friction coefficient of nano-oil at various speeds of the orbiting plate in the sliding thrust bearing was found to be less than that of pure oil over the entire orbiting speed ranges between 300 and 3000rpm. This is presumably because fullerene nanoparticles, which were inserted between the friction surfaces, improved the lubricating performance by increasing the lubricant oil viscosity and simultaneously preventing direct metal surface contacts. [Copyright &y& Elsevier]

Background: Small clinics are important in providing health care in local communities. Accurately predicting their closure would help manage health care resource allocation. There have been few studies on the prediction of clinic closure using machine learning techniques., Objective: This study aims to test the feasibility of predicting the closure of medical and dental clinics (MCs and DCs, respectively) and investigate important factors associated with their closure using machine running techniques., Methods: The units of analysis were MCs and DCs. This study used health insurance administrative data. The participants of this study ran and closed clinics between January 1, 2020, and December 31, 2021. Using all closed clinics, closed and run clinics were selected at a ratio of 1:2 based on the locality of study participants using the propensity matching score of logistic regression. This study used 23 and 19 variables to predict the closure of MCs and DCs, respectively. Key variables were extracted using permutation importance and the sequential feature selection technique. Finally, this study used 5 and 6 variables of MCs and DCs, respectively, for model learning. Furthermore, four machine learning techniques were used: (1) logistic regression, (2) support vector machine, (3) random forest (RF), and (4) Extreme Gradient Boost. This study evaluated the modeling accuracy using the area under curve (AUC) method and presented important factors critically affecting closures. This study used SAS (version 9.4; SAS Institute Inc) and Python (version 3.7.9; Python Software Foundation)., Results: The best-fit model for the closure of MCs with cross-validation was the support vector machine (AUC 0.762, 95% CI 0.746-0.777; P<.001) followed by RF (AUC 0.736, 95% CI 0.720-0.752; P<.001). The best-fit model for DCs was Extreme Gradient Boost (AUC 0.700, 95% CI 0.675-0.725; P<.001) followed by RF (AUC 0.687, 95% CI 0.661-0.712; P<.001). The most significant factor associated with the closure of MCs was years of operation, followed by population growth, population, and percentage of medical specialties. In contrast, the main factor affecting the closure of DCs was the number of patients, followed by annual variation in the number of patients, year of operation, and percentage of dental specialists., Conclusions: This study showed that machine running methods are useful tools for predicting the closure of small medical facilities with a moderate level of accuracy. Essential factors affecting medical facility closure also differed between MCs and DCs. Developing good models would prevent unnecessary medical facility closures at the national level., (©Young-Taek Park, Donghan Kim, Ji Soo Jeon, Kwang Gi Kim. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 30.08.2024.)

Organic-inorganic hybrid perovskites (OIHPs) are a promising class of materials that rival conventional semiconductors in various optoelectronic applications. However, unraveling the precise nature of their low-energy electronic structures continues to pose a significant challenge, primarily due to the absence of clear band measurements. Here, we investigate the low-energy electronic structure of CH 3 NH 3 PbI 3 (MAPI 3 ) using angle-resolved photoelectron spectroscopy combined with ab initio density functional theory. We successfully visualize the electronic structure of MAPI 3 near the bulk valence band maximum by using a laboratory photon source (He I α , 21.2 eV) at low temperature and explore its fundamental properties. The observed valence band exhibits a highly isotropic and parabolic band characterized by small effective masses of 0.20-0.21 m e , without notable spectral signatures associated with a large polaron or the Rashba effect, subjects that are intensely debated in the literature. Concurrently, our spin-resolved measurements directly disprove the giant Rashba scenario previously suggested in a similar perovskite compound by establishing an upper limit for the Rashba parameter ( α R ) of 0.28 eV Å. Our results unveil the unusually complex nature of the low-energy electronic structure of OIHPs, thereby advancing our fundamental understanding of this important class of materials.

Altermagnetism is a newly identified fundamental class of magnetism with vanishing net magnetization and time-reversal symmetry broken electronic structure. Probing the unusual electronic structure with nonrelativistic spin splitting would be a direct experimental verification of an altermagnetic phase. By combining high-quality film growth and in situ angle-resolved photoemission spectroscopy, we report the electronic structure of an altermagnetic candidate, α-MnTe. Temperature-dependent study reveals the lifting of Kramers degeneracy accompanied by a magnetic phase transition at T&#95;{N}=267  K with spin splitting of up to 370 meV, providing direct spectroscopic evidence for altermagnetism in MnTe.

Periodontitis is an oral infectious disease caused by various pathogenic bacteria, such as Porphyromonas gingivalis . Although probiotics and their cellular components have demonstrated positive effects on periodontitis, the beneficial impact of peptidoglycan (PGN) from probiotic Lactobacillus remains unclear. Therefore, our study sought to investigate the inhibitory effect of PGN isolated from L. reuteri (LrPGN) on P. gingivalis -induced inflammatory responses. Pretreatment with LrPGN significantly inhibited the production of interleukin (IL)-1β, IL-6, and CCL20 in RAW 264.7 cells induced by P. gingivalis lipopolysaccharide (LPS). LrPGN reduced the phosphorylation of PI3K/Akt and MAPKs, as well as NF-κB activation, which were induced by P. gingivalis LPS. Furthermore, LrPGN dose-dependently reduced the expression of Toll-like receptor 4 (TLR4), indicating that LrPGN inhibits periodontal inflammation by regulating cellular signaling cascades through TLR4 suppression. Notably, LrPGN exhibited stronger inhibition of P. gingivalis LPS-induced production of inflammatory mediators compared to insoluble LrPGN and proteinase K-treated LrPGN. Moreover, MDP, a minimal bioactive PGN motif, also dose-dependently inhibited P. gingivalis LPS-induced inflammatory mediators, suggesting that MDP-like molecules present in the LrPGN structure may play a crucial role in the inhibition of inflammatory responses. Collectively, these findings suggest that LrPGN can mitigate periodontal inflammation and could be a useful agent for the prevention and treatment of periodontitis.

Copper-based high-temperature superconductors share a common feature in their crystal structure, which is the presence of a CuO 2 plane, where superconductivity takes place. Therefore, important questions arise as to whether superconductivity can exist in a single layer of the CuO 2 plane and, if so, how such superconductivity in a single CuO 2 plane differs from that in a bulk cuprate system. To answer these questions, studies of the superconductivity in cuprate monolayers are necessary. In this study, we constructed a heterostructure system with a La 2- x Sr x CuO 4 (LSCO) monolayer containing a single CuO 2 plane and measured the resulting electronic structures. Monolayer LSCO has metallic and bulk-like electronic structures. The hole doping ratio of the monolayer LSCO is found to depend on the underlying buffer layer due to the interface effect. Our work will provide a platform for research into ideal two-dimensional cuprate systems.

Hund's rule coupling (J) has attracted much attention recently for its role in the description of the novel quantum phases of multi-orbital materials. Depending on the orbital occupancy, J can lead to various intriguing phases. However, experimental confirmation of the orbital occupancy dependency has been difficult as controlling the orbital degrees of freedom normally accompanies chemical inhomogeneities. Here, we demonstrate a method to investigate the role of orbital occupancy in J related phenomena without inducing inhomogeneities. By growing SrRuO 3 monolayers on various substrates with symmetry-preserving interlayers, we gradually tune the crystal field splitting and thus the orbital degeneracy of the Ru t 2g orbitals. It effectively varies the orbital occupancies of two-dimensional (2D) ruthenates. Via in-situ angle-resolved photoemission spectroscopy, we observe a progressive metal-insulator transition (MIT). It is found that the MIT occurs with orbital differentiation: concurrent opening of a band insulating gap in the d xy band and a Mott gap in the d xz/yz bands. Our study provides an effective experimental method for investigation of orbital-selective phenomena in multi-orbital materials., (© 2023. The Author(s).)

Interfaces between dissimilar correlated oxides can offer devices with versatile functionalities, and great efforts have been made to manipulate interfacial electronic phases. However, realizing such phases is often hampered by the inability to directly access the electronic structure information; most correlated interfacial phenomena appear within a few atomic layers from the interface. Here, atomic-scale epitaxy and photoemission spectroscopy are utilized to realize the interface control of correlated electronic phases in atomic-scale ruthenate-titanate heterostructures. While bulk SrRuO 3 is a ferromagnetic metal, the heterointerfaces exclusively generate three distinct correlated phases in the single-atomic-layer limit. The theoretical analysis reveals that atomic-scale structural proximity effects yield Fermi liquid, Hund metal, and Mott insulator phases in the quantum-confined SrRuO 3 . These results highlight the extensive interfacial tunability of electronic phases, hitherto hidden in the atomically thin correlated heterostructure. Moreover, this experimental platform suggests a way to control interfacial electronic phases of various correlated materials., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Divergent density of states (DOS) can induce extraordinary phenomena such as significant enhancement of superconductivity and unexpected phase transitions. Moreover, van Hove singularities (VHSs) lead to divergent DOS in 2D systems. Despite recent interest in VHSs, only a few controllable cases have been reported to date. In this work, by utilizing an atomically ultra-thin SrRuO 3 film, the electronic structure of a 2D VHS is investigated with angle-resolved photoemission spectroscopy and transport properties are controlled. By applying electric fields with alkali metal deposition and ionic-liquid gating methods, the 2D VHS and the sign of the charge carrier are precisely controlled. Use of a tunable 2D VHS in an atomically flat oxide film could serve as a new strategy to realize infinite DOS near the Fermi level, thereby allowing efficient tuning of electric properties., (© 2023 Wiley-VCH GmbH.)

Postbiotics are functional biological compounds, such as bacterial lysates (BLs) released from probiotic bacteria. Although postbiotics exert various bioactivities, the anti-inflammatory and antibiofilm activities of BLs against oral pathogenic bacteria have not been investigated. In the present study, pretreatment with BLs extracted from Lactobacillus plantarum and L. rhamnosus GG suppressed the mRNA and protein expression levels of inflammatory mediators induced by the lipopolysaccharide (LPS) of Porphyromonas gingivalis in RAW 264.7 cells. Both BLs attenuated P. gingivalis LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-κB (NF-κB), suggesting that BLs inhibit periodontal inflammatory responses by regulating the MAPK and NF-κB signaling pathways. Moreover, both BLs interfered with biofilm formation by Streptococcus mutans ; however, they did not eradicate the established S. mutans biofilm. Furthermore, both BLs downregulated gtf B, gtf C, and gtf D responsible for biofilm formation by S. mutans , suggesting that BLs reduce the synthesis of extracellular polysaccharide and thereby reduce S. mutans biofilm. Taken together, these results suggest that BLs of L. plantarum and L. rhamnosus GG can attenuate periodontal inflammation and dental caries and thus contribute to the improvement of oral health.

The aim of the study was to investigate the effect of bacteriocin-like inhibitory substance (BLIS) from Enterococcus faecium DB1 on cariogenic Streptococcus mutans biofilm. Crystal violet staining, fluorescence, and scanning electron microscopy analyses demonstrated that the BLIS from Enterococcus faecium DB1 (DB1 BLIS) inhibited S. mutans biofilm. When DB1 BLIS was co-incubated with S. mutans , biofilm formation by S. mutans was significantly reduced (p<0.05). DB1 BLIS also destroyed the preformed biofilm of S. mutans . In addition, DB1 BLIS decreased the viability of S. mutans biofilm cells during the development of biofilm formation and in the preformed biofilm. DB1 BLIS significantly decreased the growth of S. mutans planktonic cells. Furthermore, S. mutans biofilm on the surface of saliva-coated hydroxyapatite discs was reduced by DB1 BLIS. Taken together, DB1 BLIS might be useful as a preventive and therapeutic agent against dental caries caused by S. mutans ., Competing Interests: The authors declare no potential conflicts of interest., (© Korean Society for Food Science of Animal Resources.)

The purpose of this study aims at segmenting the urban forest users' market by motivation and analyzing the difference in perceived effects of urban forests. Based on a literature review, the study selected seven motivating factors of urban forest users: experiential activity, relaxatin/healing, health management, escape from everday life, daily leisure, affinity toward nature. Data were collected online from 21 to 29 Sepember 2020 with urban forest visitors. We analyzed 878 questionnaires received from those with experience of visiting an urban forest within the previous 24 months. We performed a cluster analysis to classify the subjects according to the characteristics of urban forest utilization, and assigned them to four clusters (rest in nature, family leisure, passive participation, and multiple pursuit). An additional analysis was performed to determine intergroup differences, which revealed differences in perceived benefits and healing effects of urban forests as well as satisfaction. The results of this study provide implications for urban forest operation and strategy setup.

We performed in situ angle-resolved photoemission spectroscopy (ARPES) and spin-resolved ARPES (SARPES) experiments to investigate the relationship between electronic band structures and ferromagnetism in SrRuO&#95;{3} (SRO) thin films. Our high quality ARPES and SARPES results show clear spin-lifted band structures. The spin polarization is strongly dependent on momentum around the Fermi level, whereas it becomes less dependent at high-binding energies. This experimental observation matches our dynamical mean-field theory results very well. As temperature increases from low to the Curie temperature, spin-splitting gap decreases and band dispersions become incoherent. Based on the ARPES study and theoretical calculation results, we found that SRO possesses spin-dependent electron correlations in which majority and minority spins are localized and itinerant, respectively. Our finding explains how ferromagnetism and electronic structure are connected, which has been under debate for decades in SRO.

Magnetism and spin-orbit coupling are two quintessential ingredients underlying topological transport phenomena in itinerant ferromagnets. When spin-polarized bands support nodal points/lines with band degeneracy that can be lifted by spin-orbit coupling, the nodal structures become a source of Berry curvature, leading to a large anomalous Hall effect. However, two-dimensional systems can possess stable nodal structures only when proper crystalline symmetry exists. Here we show that two-dimensional spin-polarized band structures of perovskite oxides generally support symmetry-protected nodal lines and points that govern both the sign and the magnitude of the anomalous Hall effect. To demonstrate this, we performed angle-resolved photoemission studies of ultrathin films of SrRuO 3 , a representative metallic ferromagnet with spin-orbit coupling. We show that the sign-changing anomalous Hall effect upon variation in the film thickness, magnetization and chemical potential can be well explained by theoretical models. Our work may facilitate new switchable devices based on ferromagnetic ultrathin films., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Correlated electrons in transition metal oxides exhibit a variety of emergent phases. When transition metal oxides are confined to a single-atomic-layer thickness, experiments so far have shown that they usually lose diverse properties and become insulators. In an attempt to extend the range of electronic phases of the single-atomic-layer oxide, we search for a metallic phase in a monolayer-thick epitaxial SrRuO 3 film. Combining atomic-scale epitaxy and angle-resolved photoemission measurements, we show that the monolayer SrRuO 3 is a strongly correlated metal. Systematic investigation reveals that the interplay between dimensionality and electronic correlation makes the monolayer SrRuO 3 an incoherent metal with orbital-selective correlation. Furthermore, the unique electronic phase of the monolayer SrRuO 3 is found to be highly tunable, as charge modulation demonstrates an incoherent-to-coherent crossover of the two-dimensional metal. Our work emphasizes the potentially rich phases of single-atomic-layer oxides and provides a guide to the manipulation of their two-dimensional correlated electron systems., (© 2021. The Author(s).)

We present an open-source anthropomorphic robot hand system called HRI hand. Our robot hand system was developed with a focus on the end-effector role of the collaborative robot manipulator. HRI hand is a research platform that can be built at a lower price (approximately $500, using only 3D printing) than commercial end-effectors. Moreover, it was designed as a two four-bar linkage for the under-actuated mechanism and provides pre-shaping motion similar to the human hand prior to touching an object. A URDF, python node, and rviz package is also provided to support the Robot Operating System (ROS). All hardware CAD design files and software source codes have been released and can be easily assembled and modified. The system proposed in this paper is developed with a five-finger structure, but each finger is modularized, so it can be developed with end-effectors of various shapes depending on the shape of the palm., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 The Author(s).)

Lithium-rich layered oxides show promise as high-energy harvesting materials due to their large capacities. However, questions remain regarding the large irreversible loss in capacities for the first charge-discharge cycle due to oxygen removal in lattices related to layered Li 2 MnO 3 . Herein we present detailed studies on Li-rich Mn-based layered oxides of 0.4Li 2 MnO 3 -0.6LiNi 1/3 Co 1/3 Mn 1/3 O 2 (Li-rich NCM) electrochemically activated between 2.5 V and 4.3 or 4.7 V vs. Li + /Li. Electron energy loss spectroscopy (EELS) and X-ray absorption spectroscopy (XAS) revealed unusual manganese reduction after the first charge up to a high voltage of 4.7 V. Moreover, the electronic structure did not fully recover to the original pristine of Mn 4+ state after discharge. Interestingly, these phenomena were not limited to a single particle, but were observed across the entire electrode. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) images and electron dispersive spectra (EDS) also showed a dramatic decline in oxygen content with highly porous morphologies, associated with oxygen vacancy formation following oxidation of O 2- ions to O 2 . Our analysis suggests that an unstable manganese valence state with severe defects due to oxygen vacancies may lead to large irreversible capacity loss during the first charge-discharge cycle of Li-rich layered oxides.

Background: While frameless stereotaxis can be used for shunt ventricular catheter placement in patients with smaller ventricles, the ventricular catheter is still commonly placed based on the surface anatomy of the head for patients with larger ventricles. Thus, surgical techniques and guides facilitating accurate and reliable freehand placement of the ventricular catheter still need to be devised., Methods: With the patient in a supine position and the axis of their head maintained horizontally, the guiding protractor is placed horizontally in the frontal burrhole at Kocher's point. Using the guiding angle between the head axis and the frontal horn of the lateral ventricle based on coronal head computed tomography (CT) or magnetic resonance (MR) images, the ventricular catheter is then placed in the catheter guide within the guiding protractor., Results: In 20 hydrocephalic patients with a bicaudate index >0.2 or bifrontal distance >25 mm, the ideal guiding angle ranged from 17 to 23° (mean ± standard deviation [SD], 19.6° ± 1.6°). In all these patients, ventricular catheterization was successfully achieved with only one pass of the catheter, and postoperative CT scans showed satisfactory placement of the catheter in the ipsilateral frontal horn of the lateral ventricles., Conclusions: The proposed surgical technique using a guiding protractor facilitates accurate freehand placement of a ventricular catheter for patients with a bicaudate index >0.2 or bifrontal distance >25 mm.