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The photochemical acid generation is refined from the first principles of quan-tum electrodynamics. First, we briefly review the formulation of the quantum theory of light based on the quantum electrodynamics framework to establish the probability of acid generation at a given spacetime point. The quantum mechanical acid generation is then combined with the deprotection mecha-nism to obtain a probabilistic description of the deprotection density directly related to feature formation in a photoresist. A statistical analysis of the ran-dom deprotection density is presented to reveal the leading characteristics of stochastic feature formation.

Abstract Student-created videos engage students’ interests, creativity, and content knowledge and enrich collaborative learning in STEM education. These videos enhance critical thinking and analytical skills, which are essential tools in the fields of science, technology, engineering, and mathematics (STEM). This study presents the results of such an assignment across several STEM areas (biology, chemistry, exercise science, information technology, and mathematics) at a minority-serving, liberal arts higher education institution in the southeast region of the United States. Undergraduate students (n = 557) across varied, online course modalities (synchronous and asynchronous) were required to create four problem-solving videos 3–8 min in duration. Assessment tools included a self-assessment of learning gains survey given to control and experimental groups and a post-video creation survey given only to experimental groups. Grade data was also collected from all sections. Comparing the experimental and control groups, students showed a statistically significant gain in their ability to give oral presentations, create videos, and edit videos. Qualitative data from free-response questions corroborate these gains and suggest that students also grew in content knowledge and conceptual understanding through these assignments. Our study implements a multimedia theoretical framework which suggests students learn more effectively from consuming presentations with both auditory and visual components. Our results suggest students see similar gains from producing presentations with both auditory and visual components. Further our results suggest that multimedia production enhances students’ presentation skills. From a practical perspective, this study suggests that faculty should incorporate student-created videos in online classes, which typically require oral presentations in person. Faculty are also advised to require oral and visual components within these videos to maximize learning gains from the perspective of a multimedia theoretical framework.

This case report describes a successful use of normothermic targeted temperature management (TTM) for the treatment of a 14-year-old girl with exertional heat stroke. Upon hospitalization, she exhibited a 40.5 ℃ core temperature and multiorgan failure. We immediately applied the TTM, targeting a range of 36-37 ℃. Her condition improved rapidly, with vital signs stabilized and consciousness fully regained by day 3. She experienced a bimodal pattern of rhabdomyolysis during recovery, which was managed without further complications. No neurological sequelae were observed, and all laboratory parameters were normalized before discharge on day 10. This case suggests the potential efficacy of normothermic TTM in pediatric heat stroke.

Abstract Atomic sawtooth surfaces have emerged as a versatile platform for growth of single-crystal van der Waals layered materials. However, the mechanism governing the formation of single-crystal atomic sawtooth metal (copper or gold) films on hard substrates (tungsten or molybdenum) remains a puzzle. In this study, we aim to elucidate the formation mechanism of atomic sawtooth metal films during melting–solidification process. Utilizing molecular dynamics, we unveil that the solidification of the liquid copper initiates at a high-index tungsten facet with higher interfacial energy. Subsequent tungsten facets follow energetically favourable pathways of forming single-crystal atomic sawtooth copper film during the solidification process near melting temperature. Formation of atomic sawtooth copper film is guaranteed with a film thickness exceeding the grain size of polycrystalline tungsten substrate. We further demonstrate the successful growth of centimeter-scale single-crystal monolayer hexagonal boron nitride films on atomic sawtooth copper films and explore their potential as efficient oxygen barrier.

Abstract Achieving efficient and large‐area organic solar modules via non‐halogenated solution processing is vital for the commercialization yet challenging. The primary hurdle is the conservation of the ideal film‐formation kinetics and bulk‐heterojunction (BHJ) morphology of large‐area organic solar cells (OSCs). A cutting‐edge non‐fullerene acceptor (NFA), Y6, shows efficient power conversion efficiencies (PCEs) when processed with toxic halogenated solvents, but exhibits poor solubility in non‐halogenated solvents, resulting in suboptimal morphology. Therefore, in this study, the impact of modifying the inner and outer side‐chains of Y6 on OSC performance is investigated. The study reveals that blending a polymer donor, PM6, with one of the modified NFAs, namely N‐HD, achieved an impressive PCE of 18.3% on a small‐area OSC. This modified NFA displays improved solubility in o‐xylene at room temperature, which facilitated the formation of a favorable BHJ morphology. A large‐area (55 cm2) sub‐module delivered an impressive PCE of 12.2% based on N‐HD using o‐xylene under ambient conditions. These findings underscore the significant impact of the modified Y6 derivatives on structural arrangements and film processing over a large‐area module at room temperature. Consequently, these results are poised to deepen the comprehension of the scaling challenges encountered in OSCs and may contribute to their commercialization.

In the face of escalating climate challenges, environmental sustainability has greatly become an urgent and non-negotiable priority, necessitating revolutionary advancements in energy management to reduce carbon footprints and drive profound improvements in overall sustainability. This paper presents an advanced optimization framework, PST-CESS, for managing power-sharing among multiple tenants within the centralized energy storage system (ESS). Our thorough evaluation demonstrates that the centralized ESS facilitated by PST-CESS substantially exceeds the performance of individualized ESS systems in pivotal areas such as peak load reduction, variability mitigation, and financial profitability. Specifically, the centralized ESS model achieves up to a 44.05% reduction in annual peak load for certain tenants and reduces electricity consumption variability by up to 57.67%. From a financial perspective, the centralized ESS model delivers remarkable advantages, reaching a break-even point in just 2.48 years, compared to the 5.08 years required for individualized ESS systems, even when accounting for battery capacity loss costs, also known as battery degradation costs. These results highlight the centralized ESS approach as a more economically advantageous and efficient solution, providing superior financial returns and optimized energy management for multi-tenant buildings. The strategic benefits and compelling evidence presented in this study strongly support the widespread adoption of centralized ESS models to maximize both economic and environmental benefits, establishing a new standard for sustainable energy management.

Abstract Background Salinomycin, an antibiotic, have potential as a veterinary drug for fish due to its anti-parasitic activity against several fish parasites. Thus the residual levels of salinomycin in muscles of two significant aquaculture species in Korea, olive flounder and black rockfish, were analyzed using HPLC-MS-MS. Results The proper method to analyze the residual salinomycin in fish muscles using LC-MS-MS was settled and the method was validated according to CODEX guidelines. The residues in three distinct groups for two fish species were analyzed using the matrix match calibration curves at points of five different times following oral administration. After oral administration, salinomycin rapidly breaks down in both olive flounder and black rockfish. After 7th days, the average residue in all groups of two fish spp. decreased below limit of quantitation (LOQ). Conclusion Due to low residue levels in fish muscles, salinomycin may therefore be a treatment that is safe for both fish and humans. This result could contribute to establishment of MRL (minimal residual limit) for approval of salinomycin for use in aquaculture.

Abstract Hair loss caused by malfunction of the hair follicle stem cells (HFSCs) and physical damage to the skin is difficult to recover from naturally. To overcome these obstacles to hair follicle (HF) regeneration, it is essential to understand the three-dimensional (3D) microenvironment and interactions of various cells within the HFs. Therefore, 3D cell culture technology has been used in HF regeneration research; specifically, multicellular spheroids have been generally adapted to mimic the 3D volumetric structure of the HF. In this study, we culture HF-derived cells, which are mainly composed of HFSCs, in the form of 3D spheroids using a microwell array and discuss the effects of the 3D cellular environment on HF morphogenesis by expression measurements of Sonic hedgehog signaling and stem cell markers in the HF spheroids. Additionally, the influences of microwell depth on HF spheroid formation and biological conditions were investigated. The biomolecular diffusion and convective flow in the microwell were predicted using computational fluid dynamics, which allows analysis of the physical stimulations occurring on the spheroid at the micro-scale. Although a simple experimental method using the microwell array was adopted in this study, the results provide fundamental insights into the physiological phenomena of HFs in the 3D microenvironment, and the numerical analysis is expected to shed light on the investigation of the geometric parameters of the microwell system.

The most widely used material in electron transport layers (ETL) of inverted organic solar cells (iOSCs) is zinc oxide (ZnO). However, the brittleness, inorganic nature, surface defects, and photocatalytic activity of ZnO lead to poor stability in iOSCs. Herein, the light‐soaking and thermal stability of iOSCs are substantially improved by modifying ZnO surface with polyurethane diacrylate (SAR) or urethane acrylate (OCS)‐based ultraviolet (UV) resins. The UV resins significantly reduce the energy barrier, suppress surface defects, and improve interfacial contact between ZnO ETL and the organic photoactive layer. Notably, the SAR and OCS resins mitigate the photocatalytic activity of ZnO, electrical leakage, and interfacial resistance during photoaging of OSCs. As a result, iOSCs based on modified ZnOs retain over 80% of initial efficiency under 1 sun illumination for light soaking 1000 h. Furthermore, SAR and OCS resins on ZnO surfaces form a robust crosslinked network with excellent solvent resistant properties, which result in enhanced thermal stability. These results reveal that this simple and effective approach is a promising procedure to fabricate high‐performance iOSCs.

Abstract Solution‐processed low‐bandgap semiconductors are crucial to next‐generation infrared (IR) detection for various applications, such as autonomous driving, virtual reality, recognitions, and quantum communications. In particular, III–V group colloidal quantum dots (CQDs) are interesting as nontoxic bandgap‐tunable materials and suitable for IR absorbers; however, the device performance is still lower than that of Pb‐based devices. Herein, a universal surface‐passivation method of InAs CQDs enabled by intermediate phase transfer (IPT), a preliminary process that exchanges native ligands with aromatic ligands on the CQD surface is presented. IPT yields highly stable CQD ink. In particular, desirable surface ligands with various reactivities can be obtained by dispersing them in green solvents. Furthermore, CQD near‐infrared (NIR) photodetectors are demonstrated using solution processes. Careful surface ligand control via IPT is revealed that enables the modulation of surface‐mediated photomultiplication, resulting in a notable gain control up to ≈10 with a fast rise/fall response time (≈12/36 ns). Considering the figure of merit (FOM), EQE versus response time (or −3 dB bandwidth), the optimal CQD photodiode yields one of the highest FOMs among all previously reported solution‐processed nontoxic semiconductors comprising organics, perovskites, and CQDs in the NIR wavelength range.

Abstract The simple‐structural and volatile solid additive 1,4‐dibromobenzene (DBrB) can outperform organic solar cells (OSCs) fabricated with 1,4‐diiodobenzene and 1,4‐dichlorobenzene in terms of power conversion efficiency (PCE). A remarkable PCE of 17.0% has been achieved in a binary OSC based on DBrB‐optimized photoactive materials processed from non‐halogenated solvents, which is mainly attributed to the formation of a three‐dimensional interpenetrating network and the orderly arrangement of the photoactive materials by improving the intermolecular interaction. This optimized morphology enables efficient charge transfer/transport as well as suppressed charge recombination, resulting in the simultaneous increase in all photovoltaic parameters. More importantly, we demonstrate that non‐halogenated solvent‐processed DBrB enabled PM6:Y6‐HU OSCs with an impressive PCE of 18.6%, which is the highest efficiency yet reported for binary OSCs. This study suggests that the novel DBrB volatile solid additive is an effective approach to optimizing the morphology and thereby improves the photovoltaic performance of OSCs.

Polymer solar cells (PSCs) with high power conversion efficiency (PCE) and environment-friendly fabrication are the main requirements enabling their production in industrial scale. While the use of non-halogenated solvent processing is inevitable for the PSC fabrication, it significantly reduces the processability of polymer donors (PDS) and small-molecule acceptors (SMAs). This often results in unoptimized blend morphology and limits the device performance. To address this issue, hydrophilic oligoethylene glycol (OEG) side-chains are introduced into a PD (2EG) to enhance the molecular compatibility between the PD and L8-BO SMA. The 2EG PD induces higher crystallinity and alleviates phase separation with the SMA compared to the reference PD (PM7) with hydrocarbon side-chains. Consequently, the 2EG-based PSCs exhibit a higher PCE (15.8%) than the PM7-based PSCs (PCE = 14.4%) in the ortho-xylene based processing. Importantly, benefitted from the reduced phase separation and increased crystallinity of 2EG PDS, the 2EG-based PSCs show enhanced thermal stability (84% of initial PCE after 120 h heating) compared to that of the PM7-based PSCs (60% of initial PCE after 120 h heating). This study demonstrates the potential of OEG side-chain-incorporated materials in developing efficient, stable, and eco-friendly PSCs.

Abstract Microfluidic devices have emerged as powerful tools for cell-based experiments, offering a controlled microenvironment that mimic the conditions within the body. Numerous cell experiment studies have successfully utilized microfluidic channels to achieve various new scientific discoveries. However, it has been often overlooked that undesired and unnoticed propagation of cellular molecules in such bio-microfluidic channel systems can have a negative impact on the experimental results. Thus, more careful designing is required to minimize such unwanted issues through deeper understanding and careful control of chemically and physically predominant factors at the microscopic scale. In this paper, we introduce a new approach to improve microfluidic channel design, specifically targeting the mitigation of the aforementioned challenges. To minimize the occurrence of undesired cell positioning upstream from the main test section where a concentration gradient field locates, an additional narrow port structure was devised between the microfluidic upstream channel and each inlet reservoir. This port also functioned as a passive lock that hold the flow at rest via fluid-air surface tension, which facilitated manual movement of the device even when cell attachment was not achieved completely. To demonstrate the practicability of the system, we conducted experiments and diffusion simulations on the effect of endocrine disruptors on germ cells. To this end, a bisphenol-A (BPA) concentration gradient was generated in the main channel of the system at BPA concentrations ranging from 120.8 μM to 79.3 μM, and the proliferation of GC-1 cells in the BPA gradient environment was quantitatively evaluated. The features and concepts of the introduced design is to minimize unexpected and ignored error sources, which will be one of the issues to be considered in the development of microfluidic systems to explore extremely delicate cellular phenomena.

Abstract Over the past few decades, research on life in space has increased. Owing to the expensive nature of and the challenges associated with conducting experiments in real space, clinostats, which continuously randomize the gravity vector by using motors, have been used to generate simulated microgravity (SMG) on Earth. Herein, by using a 3D printing method, we develop a customized small-sized clinostat (CS clinostat) that is easy to manufacture, inexpensive, and robust. Moreover, we develop and fabricate a gas-permeable polydimethylsiloxane culture dish that fits inside the CS clinostat. To validate SMG generation, ovarian cancer cells (OV- 90, TOV-21G, and Caov-3) were applied to demonstrate a significant reduction in caveolin-1 expression, a biomarker of SMG, indicating SMG generation. The proposed CS clinostat system has good accessibility for SMG research, which makes it useful as a tool for biologists, who are unfamiliar with conventional clinostat equipment, to conduct preliminary studies in the space environment.

We present a global optimization routine for the variational quantum algorithms, which utilizes the dynamic tunneling flow. Originally designed to leverage information gathered by a gradient-based optimizer around local minima, we adapt the conventional dynamic tunneling flow to exploit the distance measure of quantum states, resolving issues of extrinsic degeneracy arising from the parametrization of quantum states. Our global optimization algorithm is applied to the variational quantum eigensolver for the transverse-field Ising model to demonstrate the performance of our routine while comparing it with the conventional dynamic tunneling method, which is based on the Euclidean distance measure on the parameter space.

Measurement(s) Metabolomics Technology Type(s) high-performance liquid chromatography-electrospray ionisation tandem mass spectrometry Sample Characteristic - Organism Embryophyta

Abstract Background As the COVID-19 (Coronavirus disease 2019) pandemic is prolonged, psychological responses to the pandemic have changed, and a new scale to reflect these changes needs to be developed. In this study, we attempt to develop and validate the COVID-19 Impact Scale (CIS) to measure the psychological stress responses of the COVID-19 pandemic, including emotional responses and difficulty with activities of daily living. Methods We recruited 2152 participants. Participants completed the CIS, the Fear of COVID-19 Scale (FCV-19S), and other mental health related measures. The factor structure, reliability, and validity of the CIS were analyzed. In addition, the validity of the scale was confirmed by its relationships to the existing measures assessing fear of COVID-19, depression, anxiety, subjective well-being, and suicidal ideation. Results Using exploratory factor analysis (N 1 = 1076), we derived a one-factor structure. In confirmatory factor analysis (N 2 = 1076), the one-factor model showed good to excellent fitness. The CIS was positively correlated with depression, anxiety, suicidal ideation, fear of COVID-19 and negatively correlated with subjective well-being. The FCV-19S did not show significant correlations with subjective well-being or suicidal ideation, and FCV-19S’s explanatory powers on depression and anxiety were lower than those of the CIS. Conclusions These results support that the CIS is a valid assessment of emotional problems and deterioration of the quality of life caused by the COVID-19 pandemic. Finally, the limitations of this study and future research directions are discussed.

Proximal humerus fractures are the third most common fractures, totaling 4% to 5% of all fractures. Here, we present the case of a 39-year-old man with a dislocated four-part fracture of the proximal humerus with a huge bony Bankart lesion. Preoperatively, the bony Bankart lesion of the glenoid was not visualized on computed tomography scans or magnetic resonance imaging because the fracture of the proximal humerus was comminuted, displaced, and complex. It was planned for only the humerus fracture to be treated by open reduction and internal fixation using a locking plate. However, a fractured fragment remained under the scapula after reduction of the dislocated humeral head. This was mistaken for a dislocated bone fragment of the greater tuberosity and repositioning was attempted. After failure, visual confirmation showed that the bone fragment was a piece of the glenoid. After reduction and fixation of this glenoid part with suture anchors, we acquired a well-reduced fluoroscopic image. Given this case of complex proximal humerus fracture, a glenoid fracture such as a bony Bankart lesion should be considered preoperatively and intraoperatively in such cases.

This paper proposes an energy-efficient multi-level sleep mode control for periodic transmission (MSC-PUT) in private fifth-generation (5G) networks. In general, private 5G networks meet IIoT requirements but face rising energy consumption due to dense base station (BS) deployment, particularly impacting operating expenses (OPEX). An approach of BS sleep mode has been studied to reduce energy consumption, but there has been insufficient consideration for the periodic uplink transmission of industrial Internet of Things (IIoT) devices. Additionally, 5G New Reno’s synchronization signal interval limits the effectiveness of the deepest sleep mode in reducing BS energy consumption. By addressing this issue, the aim of this paper is to propose an energy-efficient multi-level sleep mode control for periodic uplink transmission to improve the energy efficiency of BSs. In advance, we develop an energy-efficient model that considers the trade-off between throughput impairment caused by increased latency and energy saving by sleep mode operation for IIoT’s periodic uplink transmission. Then, we propose an approach based on proximal policy optimization (PPO) to determine the deep sleep mode of BSs, considering throughput impairment and energy efficiency. Our simulation results verify the proposed MSC-PUT algorithm’s effectiveness in terms of throughput, energy saving, and energy efficiency. Specifically, we verify that our proposed MSC-PUT enhances energy efficiency by nearly 27.5% when compared to conventional multi-level sleep operation and consumes less energy at 75.21% of the energy consumed by the conventional method while incurring a throughput impairment of nearly 4.2%. Numerical results show that the proposed algorithm can significantly reduce the energy consumption of BSs accounting for periodic uplink transmission of IIoT devices.

Aquaculture, a crucial sector of the global food industry, faces a myriad of issues due to parasitic invasions. One such parasite, Microcotyle sebastis, which afflicts Korean rockfish in South Korea, has a significant economic impact. The impending danger of resistance to traditional anthelmintics necessitates the exploration of new antiparasitic candidates. Although the efficacy of salinomycin against aquatic parasites such as ciliates and sporozoans is known, its influence on monogeneans has yet to be studied. Therefore, this study investigated the efficacy and safety of salinomycin for the treatment of M. sebastis infections, presenting the first exploration of salinomycin’s therapeutic potential against monogeneans. In vitro examinations revealed a minimum effective concentration of salinomycin of 5 mg/kg, which led to necrosis of the haptor upon dislodging from the gill filaments. The one-time oral administration of the drug at concentrations of 5 mg/kg and 10 mg/kg showed a significant dose-dependent reduction in parasite counts, with no apparent behavioral side effects in Korean rockfish. Biochemical analyses monitored the liver, heart, and kidney enzymes, specifically aspartate transaminase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN), and creatine kinase–myocardial band (CK-MB). At both 20 °C and 13 °C, no significant differences were observed in the levels of AST and ALT. However, at 20 °C, alterations in BUN levels were evident on Day 14, a deviation not observed at 13 °C. The CK-MB analysis revealed elevated enzyme levels at both temperatures when compared to the control group, reflecting the similar changes observed in terrestrial animals administered salinomycin. The biochemical data suggest that the oral administration of salinomycin is potentially more favorable at 13 °C than at 20 °C. Although our findings warrant further comprehensive studies, including on the long-term and potential effects on nontarget species and water quality, they also suggest that salinomycin could be considered as an alternative or adjunctive treatment if resistance to the currently used praziquantel against M. sebastis is confirmed.

This paper proposes a novel energy-conscious access point ( $e$ AP) system with cross-layer design to increase the energy efficiency of IoT devices in IEEE 802.11 Wi-Fi networks for reliable IoT services. The proposed $e$ AP system controls the energy resources of IoT devices to extend the lifetime of the IoT device. For this purpose, we develop a new $e$ AP system that considers a cross-layer design with a prompt TCP ACK transmit function, a caching-and-retransmit IoT data function, and a multiple IoT data aggregate function to improve the energy efficiency of the IoT device. In addition, the proposed $e$ AP system has a device energy management module that precisely controls operating parameters, such as the transmission period of IoT packets, the delivery of traffic indication message (DTIM) value of IoT devices, and the transmitting power of IoT devices. These features extend the lifetime of the battery-powered IoT devices while satisfying service requirements for reliable IoT services. The long listening time of TCP ACK messages in receive mode (Rx) results in the high energy consumption of IoT devices due to the large round trip time. The proposed $e$ AP system reduces the reception time of TCP ACK messages in the IoT device, using the prompt TCP ACK transmit function in the $e$ AP. This reduces the long Rx mode time for TCP ACK reception, and increases the short sleep mode time, which results in increase of the energy efficiency of the IoT device. In the energy-saving analyses, we formulate an energy consumption model for the IoT device, and determine the energy-saving gain when the IoT device uses the $e$ AP system model, compared to a legacy AP system model. Our performance evaluation results verify that the proposed $e$ AP system achieves a maximum improvement in energy efficiency of approximately 88%, and 8.4 times improvement in the expected lifetime of the IoT device, compared to the legacy AP system model.

Aurantii Fructus Immaturus (AFI), extensively used in traditional herbal medicine, is known to have diverse physiological effects against various diseases, including obesity, diabetes, and cardiovascular disease. However, the effects of AFI on the immune system, especially natural killer (NK) cells, remain largely unknown. We aimed to investigate the effect of AFI on NK cell activity in vitro and in vivo and to elucidate the underlying mechanisms. Further, we verified the anticancer efficacy of AFI in a mouse lung metastasis model, underscoring the therapeutic potential of AFI in cancer therapy. Our results revealed that AFI significantly enhanced the cytolytic activity of NK cells in a dose-dependent manner, accompanied by an increase in the expression of NK cell-activating receptors, especially NKp30 and NKp46. AFI treatment also increased the expression of cytolytic granules, including granzyme B and perforin. Furthermore, the expression of CD107a, a degranulation marker, was increased upon treatment with AFI. A signaling study using western blot analysis demonstrated that the phosphorylation of extracellular signal-regulated kinase (ERK) was involved in increasing the NK cell activity following AFI treatment. In the in vivo study performed in mice, oral administration of AFI markedly enhanced the cytotoxic activity of spleen mononuclear cells against YAC-1 cells, which was accompanied by NKp46 upregulation. In addition, we confirmed that cancer metastasis was inhibited in a mouse cancer metastasis model, established using the mouse melanoma B16F10 cell line, by the administration of AFI in vivo. Collectively, these results indicate that AFI enhances NK cell-mediated cytotoxicity in vitro and in vivo via activation of the ERK signaling pathway and suggest that AFI could be a potential supplement for cancer immunotherapy.

The COVID-19 pandemic has led to an abrupt transition from face-to-face learning to online learning, which has also affected the mental health of college students. In this study, we examined the relationship between students’ adjustment to online learning and their mental health by using the Dual-Continua Model. The model assumes that mental disorder and mental well-being are related yet distinct factors of mental health. For this purpose, 2,933 college students completed an online survey around the beginning of the Fall semester of 2020 (N = 1,724) and the Spring semester of 2021 (N = 1,209). We assessed participants’ mental well-being, mental disorders, and academic distress by means of the online survey. In addition, we incorporated grades and log data accumulated in the Learning Management System (LMS) as objective learning indicators of academic achievement and engagement in online learning. Results revealed that two dimensions of mental health (i.e., mental well-being and mental disorder) were independently associated with all objective and subjective online learning indicators. Specifically, languishing (i.e., low levels of mental well-being) was negatively associated with student engagement derived from LMS log data and academic achievement and was positively associated with self-reported academic distress even after we controlled for the effects of mental disorder. In addition, mental disorder was negatively related to student engagement and academic achievement and was positively related to academic distress even after we controlled for the effects of mental well-being. These results remained notable even when we controlled for the effects of sociodemographic variables. Our findings imply that applying the Dual-Continua Model contributes to a better understanding of the relationship between college students’ mental health and their adaptation to online learning. We suggest that it is imperative to implement university-wide interventions that promote mental well-being and alleviate psychological symptoms for students’ successful adjustment to online learning.

With the emergence of various Internet of Things (IoT) technologies, energy-saving schemes for IoT devices have been rapidly developed. To enhance the energy efficiency of IoT devices in crowded environments with multiple overlapping cells, the selection of access points (APs) for IoT devices should consider energy conservation by reducing unnecessary packet transmission activities caused by collisions. Therefore, in this paper, we present a novel energy-efficient AP selection scheme using reinforcement learning to address the problem of unbalanced load that arises from biased AP connections. Our proposed method utilizes the Energy and Latency Reinforcement Learning (EL-RL) model for energy-efficient AP selection that takes into account the average energy consumption and the average latency of IoT devices. In the EL-RL model, we analyze the collision probability in Wi-Fi networks to reduce the number of retransmissions that induces more energy consumption and higher latency. According to the simulation, the proposed method achieves a maximum improvement of 53% in energy efficiency, 50% in uplink latency, and a 2.1-times longer expected lifespan of IoT devices compared to the conventional AP selection scheme.

Medication-related osteonecrosis of the jaw (MRONJ) has chiefly involved patients receiving medications for the treatment of bone-related malignancies. The surgical methods are now cautiously recommended as the treatment option for MRONJ. The purpose of this retrospective study was to report new bone formation and examine possible factors influencing spontaneous bony bridge formation by using an R-plate for reconstruction without any graft material after segmental mandibulectomy in patients with MRONJ. A cohort of 54 patients who underwent mandibulectomy between 2017 and 2022 by a single operator were included. Of them, 14 MRONJ patients (12 females and 2 males) were selected based on the inclusion criteria. Data on new bone formation, bony bridge formation, R-plate fracture, patient age, and type and duration of medication were collected. The mean age of the patients was 74.8 ± 9.3 years. All patients showed new bone formation, and 71.4% showed bony bridge formation within a year after surgery. The older the patient, the lower was the tendency for bony bridge formation in the defect (p = 0.035). Statistical analysis was performed using Fisher’s exact test. Preservation of the periosteum might be one of the most important contributing factors to new bone formation, serving as an optimal treatment option for reconstruction after segmental mandibulectomy in patients with MRONJ.

Loop-mediated isothermal amplification (LAMP) is one of the most widely used isothermal amplification technologies in molecular diagnostics. However, LAMP operates at a high temperature of 65 °C; thus, operating LAMP at a lower temperature is desirable to maximize its usefulness for on-site diagnosis. In this study, we propose a new version of LAMP, termed low-temperature LAMP, which operates at the physiological temperature of 37 °C. Low-temperature LAMP differs from conventional LAMP operating at 65 °C in terms of the concentrations of MgSO4 and deoxyribonucleoside triphosphates (dNTPs), as well as the lengths of DNA probes, which are crucial for the execution of low-temperature LAMP. Under the optimal conditions, the amplification efficiency of low-temperature LAMP is comparable to that of conventional LAMP. In addition, the ligation reaction at 37 °C, which is necessary to detect actual target nucleic acids, is combined without altering the temperature, enabling the identification of miR-21, a cancer-promoting oncogenic miRNA, with high sensitivity and selectivity. The method described in this paper does not require expensive DNA modifications or special additives and would facilitate the widespread application of LAMP in facility-limited or point-of-care settings, paving the way to improvements in other isothermal-amplification-based techniques.

The realisation of film made up of different compositions using colloidal QD inks remains a challenge because of redispersing of underlying films by polar solvents. Here, the authors introduce aromatic ligands to achieve QD inks in weakly-polar solvents that enable fabrication of multi-compositional films.

The number of elderly people suffering from dementia, a senile disease, is increasing day by day due to the rapid aging of the population. As a result, social and economic costs are also gradually increasing. To prevent such monetary losses, a system that can operate at a low cost is needed to care for dementia patients. Therefore, this research proposes a sensor-based deviant behavior detection system that allows caregivers to easily manage dementia patients even if they are not in the same location as their dementia patients at a low cost. In this research, the autoencoder and the LSTM models were used together, because deviance behavior is difficult to obtain labeled data. The autoencoder model is a representative unsupervised learning model, which can be used to extract characteristics of data, and was used to learn characteristics of normal behavioral data. The LSTM model is used to determine the deviant behavior from output outlier data that exceeds the threshold in the autoencoder. As a result of the experiment, each model achieved more than 96% and more than 99% accuracy. This research is expected to help caregivers of dementia patients manage the elderly with dementia more inexpensively and efficiently.

The product design major was formally established in 2011 and has been an important part of Chinese art education since then. At the same time, it has laid a solid foundation for the development of China’s higher education. Therefore, the product design major occupies an important position in China’s higher education and plays an irreplaceable role in cultivating industrial design talents for the country. With the continuous development and progress of national education, the teaching of product design is also constantly innovating, in order to better improve the teaching effect of product design and cultivate more product design professionals for the country. The purpose of this paper is to study the teaching of product design major based on intelligent network teaching, establish an intelligent network teaching system, and carry out intelligent network teaching experiment of product design major based on this system. The experiment concluded that the overall satisfaction of the students majoring in product design on the intelligent network teaching reached 82%, and the intelligent network teaching mode also increased the outstanding performance rate of the students majoring in product design by 30%.

Microstrip signal lines covered with a dielectric layer are used to reduce far-end crosstalk (FEXT) noise from adjacent lines. When minimizing FEXT noise, the permittivity of the dielectric layer should be higher than that of the substrate. When the permittivity is close to that of the substrate, the thickness of the covering dielectric layer is much larger than that of the substrate. We here present a novel means of reducing FEXT noise in microstrip lines covered with a dielectric layer using a rectangular (R)-shaped groove. When an R-shaped groove is created in the covering dielectric layer or substrate of the microstrip lines, FEXT noise is suppressed in the absence of the above conditions. To analyze the underlying mechanism, we studied the circuit parameters and electric field distribution in the microstrip lines. To confirm the improvements afforded by our methods, we compared simulated and measured data of our new structures to those of other structures.

Abstract Colloidal quantum dots (CQDs) are of interest for optoelectronic applications owing to their tunable properties and ease of processing. Large‐diameter CQDs offer optical response in the infrared (IR), beyond the bandgap of c‐Si and perovskites. The absorption coefficient of IR CQDs (≈104 cm−1) entails the need for micrometer‐thick films to maximize the absorption of IR light. This exceeds the thickness compatible with the efficient extraction of photogenerated carriers, a fact that limits device performance. Here, CQD bulk heterojunction solids are demonstrated that, with extended carrier transport length, enable efficient IR light harvesting. An in‐solution doping strategy for large‐diameter CQDs is devised that addresses the complex interplay between (100) facets and doping agents, enabling to control CQD doping, energetic configuration, and size homogeneity. The hetero‐offset between n‐type CQDs and p‐type CQDs is manipulated to drive the transfer of electrons and holes into distinct carrier extraction pathways. This enables to form active layers exceeding thicknesses of 700 nm without compromising open‐circuit voltage and fill factor. As a result, >90% charge extraction efficiency across the ultraviolet to IR range (350–1400 nm) is documented.

The aim of the study was to develop a new comprehensive reading assessment battery for multi-ethnic and multilingual learners in Malaysia. Using this assessment battery, we examined the reliability, validity, and dimensionality of the factors associated with reading difficulties/disabilities in the Malay language, a highly transparent alphabetic orthography. In order to further evaluate the reading assessment battery, we compared results from the assessment battery with those obtained from the Malaysian national screening instrument. In the study, 866 Grade 1 children from multi-ethnic and multilingual backgrounds from 11 government primary schools participated. The reading assessment battery comprised 13 assessments, namely, reading comprehension, spelling, listening comprehension, letter name knowledge, letter name fluency, rapid automatized naming, word reading accuracy, word reading efficiency, oral reading fluency, expressive vocabulary, receptive vocabulary, elision, and phonological memory. High reliability and validity were found for the assessments. An exploratory factor analysis yielded three main constructs: phonological-decoding, sublexical-fluency, and vocabulary-memory. Phonological-decoding was found to be the most reliable construct that distinguished between at-risk and non-at-risk children. Identifying these underlying factors will be useful for detecting children at-risk for developing reading difficulties in the Malay language. In addition, these results highlight the importance of including a range of reading and reading-related measures for the early diagnosis of reading difficulties in this highly transparent orthography.

Abstract We investigate massless n-point one-loop amplitudes of the open RNS superstring with two external fermions and determine their worldsheet integrands. The contributing correlation functions involving spin-1/2 and spin-3/2 operators from the fermion vertices are evaluated to any multiplicity. Moreover, we introduce techniques to sum these correlators over the spin structures of the worldsheet fermions such as to manifest all cancellations due to spacetime supersymmetry. These spin sums require generalizations of the Riemann identities among Jacobi theta functions, and the results can be expressed in terms of doubly-periodic functions known from the mathematics literature on elliptic multiple zeta values. On the boundary of moduli space, our spin-summed correlators specialize to compact representations of fermionic one-loop integrands for ambitwistor strings.

Tonpilz transducers are desirable for their superior performance in underwater target detection and communication applications. Several design schemes to widen their bandwidth have been reported, but these schemes often involve a complex structure or arrangement of additional components. In this study, a simple design is proposed to improve the bandwidth of a multimode Tonpilz transducer by using a non-uniform drive section that consists of piezoelectric stacks of various thicknesses. The efficacy of the design is illustrated with a multimode Tonpilz transducer having three lead zirconate titanate (PZT) stacks of different thicknesses. A new equivalent circuit was developed to analyze the frequency response of the transducer incorporating the non-uniform drive section and was used for rigorous analysis of the effects of varying the position and thickness of the non-uniform stacks on the transmitting characteristics of the transducer. The validity of the design was verified through the fabrication and characterization of a prototype multimode Tonpilz transducer. The developed structure can be readily extended to an arbitrary number of stacks in the Tonpilz transducer with any number of PZT disks in each stack.

Metal halide perovskites have been investigated for the next-generation light-emitting materials because of their advantages such as high photoluminescence quantum yield (PLQY), excellent color purity, and facile color tunability. Recently, red- and green-emissive perovskite light-emitting diodes (PeLEDs) have shown an external quantum efficiency (EQE) of over 20%, whereas there is still room for improvement for blue emissive PeLEDs. By controlling the halide compositions of chloride (Cl−) and bromide (Br−), the bandgap of perovskites can be easily tuned for blue emission. However, halide segregation easily occurrs in the mixed-halide perovskite under light irradiation and LED operation because of poor phase stability. Here, we explore the effect of A-site cation engineering on the phase stability of the mixed-halide perovskites and find that a judicious selection of low dipole moment A cation (formamidinium or cesium) suppresses the halide segregation. This enables efficient bandgap tuning and electroluminescence stability for sky blue emissive PeLEDs over the current density of 15 mA/cm2.

Low-intensity winds can be useful power sources in the context of energy harvesting. This study aims to enhance the power generation capacity of a super micro wind turbine (SMWT) in low-intensity winds by modifying the blade geometry, which cannot be realized in conventional wind turbines owing to the stress concentration. By controlling the curved angle (θ) in the middle of the blade, the rotor performance can be improved, and the rotor diameter can be reduced to increase installation density. Experimental results indicated that the optimal θ value was 105°, at which the AC voltage was improved by 7.4% compared to that in the case of the basic model with θ = 0°. The maximum electric power output was 9.333 μW and the load resistance was 47.62 kΩ. Moreover, a computational fluid dynamics analysis was performed to clarify the pressure field and streamlines on and around the blade to demonstrate the aerodynamic performance of the SMWT. The proposed blade geometry is one of many possible designs that can enhance extremely small wind turbines for energy harvesting.

Tin disulfide (SnS2) has attracted much attention as a two-dimensional (2D) material. A high-quality, low-temperature process for producing 2D materials is required for future electronic devices. Here, we investigate tin disulfide (SnS2) layers deposited via atomic layer deposition (ALD) using tetrakis(dimethylamino)tin (TDMASn) as a Sn precursor and H2S gas as a sulfur source at low temperature (150° C). The crystallinity of SnS2 was improved by H2S gas annealing. We carried out H2S gas annealing at various conditions (250° C, 300° C, 350° C, and using a three-step method). Angle-resolved X-ray photoelectron spectroscopy (ARXPS) results revealed the valence state corresponding to Sn4+ and S2- in the SnS2 annealed with H2S gas. The SnS2 annealed with H2S gas had a hexagonal structure, as measured via X-ray diffraction (XRD) and the clearly out-of-plane (A1g) mode in Raman spectroscopy. The crystallinity of SnS2 was improved after H2S annealing and was confirmed using the XRD full-width at half-maximum (FWHM). In addition, high-resolution transmission electron microscopy (HR-TEM) images indicated a clear layered structure.

We report the effect of zirconium oxide (ZrO2) layers on the electrical characteristics of multilayered tin disulfide (SnS2) formed by atomic layer deposition (ALD) at low temperatures. SnS2 is a two-dimensional (2D) layered material which exhibits a promising electrical characteristics as a channel material for field-effect transistors (FETs) because of its high mobility, good on/off ratio and low temperature processability. In order to apply these 2D materials to large-scale and flexible electronics, it is essential to develop processes that are compatible with current electronic device manufacturing technology which should be conducted at low temperatures. Here, we deposited a crystalline SnS2 at 150 °C using ALD, and we then annealed at 300 °C. X-ray diffraction (XRD) and Raman spectroscopy measurements before and after the annealing showed that SnS2 had a hexagonal (001) peak at 14.9° and A1g mode at 313 cm−1. The annealed SnS2 exhibited clearly a layered structure confirmed by the high resolution transmission electron microscope (HRTEM) images. Back-gate FETs with SnS2 channel sandwiched by top and bottom ZrO2 on p++Si/SiO2 substrate were suggested to improve electrical characteristics. We used a bottom ZrO2 layer to increase adhesion between the channel and the substrate and a top ZrO2 layer to improve contact property, passivate surface, and protect from process-induced damages to the channel. ZTZ (ZrO2/SnS2/ZrO2) FETs showed improved electrical characteristics with an on/off ratio of from 0.39×103 to 6.39×103 and a mobility of from 0.0076 cm2/Vs to 0.06 cm2/Vs.

The solar updraft tower (SUT) is a renewable power generation system that uses natural air convection from the ground that is heated by solar radiation. Placing flow-guide structures within the collector of the SUT can enhance aerodynamic performance, and hence, increase the kinetic power. Here, we propose a central guide post (CGP) structure in the SUT that controls updraft flow. The effect of the CGP geometry on aerodynamic performance was investigated using computational fluid dynamics modeling (ANSYS Fluent 19.2) to show that a CGP can play a positive role by preventing stagnation of the airflow at the center of the collector, resulting in increased kinetic power output (up to ~2%). However, excessively long CGPs retarded airflow, resulting in a dramatic decrease in kinetic power output. We also investigated a system with both a CGP (to improve aerodynamic performance and minimize energy loss) and a heat-exchange baffle (to maximize thermal energy transfer). When installed with a proper distance between components, the CGP and baffle showed a combined effect of increasing the kinetic power output by up to 10%. We expect that our proposed method using the CGP and baffle system will contribute to the development of better future SUT technology.

The solar updraft tower (SUT) is a renewable power generation system that uses the natural convection phenomenon of the ground’s air heated by solar radiation. The baffle is a thermo-fluid dynamic structure that improves the heat exchange efficiency and has been recently reported to be a useful tool to increase the output of the SUT. However, one of the less well-known issues is the relationship between the thermo-fluid dynamic characteristics of the flow in the collector of the SUT and the installation location of the baffle and how this affects the power output and SUT efficiency. In this study, the positive and negative thermo-fluid dynamic effects of the baffle, which vary depending on the installation location, are quantitatively analyzed, and the best location is predicted where the overall kinetic power generated by the SUT is maximized. The target SUT model consists of a chimney (12 m height and 0.25 m diameter) and a collector (1 m height and 10 m diameter), and a total of eight model cases are calculated. The results confirm that the kinetic power is lower or higher than that of the control model having no baffle, depending on the baffle installation location. When the position of the baffle is 4.5 m from the center, the increase in kinetic power is maximized by 8.43%. Two important conclusions are that the baffle should interfere minimally with the progress of the main flow into the chimney, generating kinetic power, and at the same time, the baffle should isolate the inner recirculating flow in order to accumulate the heat in the collector so that the natural convection strength is maximized. The perspective gained from the resulting data is useful for SUT design and for pursuing a higher efficiency in the future.

The rim seal of the gas turbine is intended to protect the material of the turbine disk from hot combustion gases. The study of the rim seal structure is important to minimise the coolant flow and maximise the sealing effect. In this paper, a wave-shaped rim seal for stator disks is proposed and its effect is confirmed by numerical analysis. To characterise the flow phenomena near the wave-shaped rim seal, a simplified model of the wave-shaped rim seal (Type 1 model), which excludes the rotor blade and stator vane, is analysed and compared with the conventional rim seal. Then, through analysis of the wave-shaped rim seal geometry (Type 2 model), which includes the rotor blade and stator vane, a reduction in egress and ingress flow was observed owing to the wave-shaped rim seal, and the sealing effectiveness on the stator disk of turbine was increased by up to 3.8%. Implementation of the wave-shape geometry in the radial seal is a novel choice for turbine designers to consider in future for better-performing and more-efficient turbines.

Solar updraft towers (SUTs) are used for renewable power generation, taking advantage of the thermal updraft air flow caused by solar energy. Aerodynamic devices have been applied to SUTs to improve their performance and the baffle is one such device. Here, we investigate the effect of baffle installation on the thermo-fluid dynamic phenomena in the collector of an SUT and how it enhances the overall SUT performance using computational fluid dynamics analysis. Two geometric parameters (height and width of baffle) and two thermal boundary conditions of the baffle (adiabatic condition and heat flux condition) were tested through simulations with 10 different models. The vortex generated by the baffle has a positive effect on the delivery of heat energy from the ground to the main flow; however, one disadvantage is that the baffle inherently increases the resistance of the main flow. Over 3% higher kinetic power was achieved with some of the simulated baffle models. Therefore, an optimum design for baffle installation can be achieved by considering the positive and negative thermo-fluid dynamics of baffles.