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The purpose of this study was to determine the feasibility of using an electrical low pressure impactor (ELPI) for analyzing residual particles in a Si epitaxial growth process chamber and establish an application technique. Prior to experimental measurements, some preliminary works were conducted, including an inlet improvement of a cascade impactor, vacuum fitting fastening and flow rate adjustment, and a vacuum leak test. After that, residual particles in the process chamber were measured during N2 gas purge using an ELPI due to its advantages including the real-time measurement of particles and the ability to separate and collect particles by their diameters. In addition, ELPI could be used to obtain particle size distribution and see the distribution trend for both number and mass concentration. The results of the real-time analysis of the total particle count revealed that the concentration at the endpoint compared to that at the beginning of the measurement by decreased 36.9%. Scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM–EDS) analysis of collected particles was performed using two types of substrates: Al foil and a Si wafer. The results showed that most particles were Si particles, while few particles had Si and Cl components. ELPI has the clear advantages of real-time particle concentration measurement and simultaneous collection. Thus, we believe that it can be more actively used for particle measurement and analysis in the semiconductor industry, which has many critical micro/nanoparticle issues.

We synthesized Sr- and W-doped BaTiO3 (BTO) polycrystals by using a solid-state reaction method. The X-ray diffraction results showed that Sr and W atoms occupied the Ba and Ti sites in tetragonal BTO, respectively, and there were changes in the lattice constants and the volumes in the Sr- and W-doped BTO. We found a change in the latent heat and the Curie temperature (TC) during the transition between the ferroelectric and paraelectric phases while increasing the contents of Sr and W in the Sr- and W-doped BTO. This can be explained by the fact that the doping of Sr and W atoms in BTO prevented a distinct transition between the ferroelectric tetragonal and paraelectric cubic structures by decreasing the c/a ratio to a value close to unity. This study shows a way toward a strategy for modulating a crystal structure by using proper dopants for future applications in ferroelectricity-based devices.

Rotavirus causes a gastrointestinal tract infection that primarily affects young children. Due to the COVID-19 pandemic, individuals infected with the virus were subjected to quarantine measures, with strong emphases on personal hygiene and social distancing. The present study aimed to evaluate the characteristics of rotaviruses and compare the prevalence of rotavirus infection before and during the COVID-19 pandemic. This nationwide representative study was conducted using data acquired from the National Health Insurance Service between 2010 and 2021. We analyzed the data of patients younger than 12 months old who were diagnosed with rotavirus enteritis between January 2010 and December 2021. During the study period, a total of 34,487 infants younger than 12 months were diagnosed with rotavirus enteritis in South Korea. During the two-year COVID-19 pandemic (2020–2021), the rate of decline was significant (5843 cases in 2010 and 1125 in 2019), and by 2021, the total number of patients was almost negligible, as there are only 18 cases in 2021. A significant increase in the ratio of low birth weight (LBW) infants of inpatient department was observed from 2010 to 2021 (4.86% in 2010; 7.77% in 2019; and 23.08% in 2021), indicating that LBW infants are more vulnerable than infants born with normal weight. Average medical expenses related to rotavirus infections also declined significantly from 3,789,443,998 per year (pre-pandemic) to 808,353,795 per year (pandemic). Overall, personal hygiene and social distancing may play important roles in reducing rotavirus infections. However, further studies are needed to determine whether this decreasing trend persists after quarantine and whether the social life of individuals resumes.

Based on traditional pharmacological applications and partial in vitro data, Cynanchum atratum (CA) is proposed to act on skin whitening. However, its functional evaluation and underlying mechanisms have yet to be identified. This study aimed to examine the anti-melanogenesis activity of CA fraction B (CAFB) on UVB-induced skin hyperpigmentation. Forty C57BL/6j mice were exposed to UVB (100 mJ/cm2, five times/week) for eight weeks. After irradiation, CAFB was applied to the left ear once a day for 8 weeks (the right ear served as an internal control). The results showed that CAFB significantly reduced melanin production in the ear skin, as indicated by the gray value and Mexameter melanin index. In addition, CAFB treatment notably decreased melanin production in α-MSH-stimulated B16F10 melanocytes, along with a significant reduction in tyrosinase activity. Cellular cAMP (cyclic adenosine monophosphate), MITF (microphthalmia-associated transcription factor), and tyrosinase-related protein 1 (TRP1) were also noticeably downregulated by CAFB. In conclusion, CAFB is a promising ingredient for treating skin disorders caused by the overproduction of melanin and its underlying mechanisms involving the modulation of tyrosinase, mainly mediated by the regulation of the cAMP cascade and MITF pathway.

Neuroinflammation causes various neurological disorders, including depression and neurodegenerative diseases. Therefore, regulation of neuroinflammation is a promising therapeutic strategy for inflammation-related neurological disorders. This study aimed to investigate whether yomogin, isolated from Artemisia iwayomogi, has anti-neuroinflammatory effects. First, we evaluated the effects of yomogin by assessing pro-inflammatory mediators and cytokines in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. The results showed that yomogin inhibited the increase in neuroinflammatory factors, including nitric oxide, inducible nitric oxide synthase, cyclooxygenase-2, interleukin-6, and tumor necrosis factor-α, and suppressed phosphorylation of c-Jun N-terminal kinase, extracellular signal-regulated kinase and p38, which participate in the mitogen-activated protein kinase (MAPK) pathway. To confirm these effects in vivo, we measured the activation of astrocyte and microglia in LPS-injected mouse brains. Results showed that yomogin treatment decreased astrocyte and microglia activations. Collectively, these results suggest that yomogin suppresses neuroinflammation by regulating the MAPK pathway and it could be a potential candidate for inflammation-mediated neurological diseases.

A CFBC (Circulating Fluidized Bed Combustor) boiler for combusted SRF (Solid Refused Fuel) is designed for solid waste combustion and power generation. The boiler consumes about 200 tons/day of SRF and generates 60 ton/h of steam or 10 MWe in electricity. The boiler is designed to burn pelletized waste fuel made of municipal solid waste collected from a town with a population of 400,000. Heat and mass balance calculations over the combustor and at each boiler section were performed and compared between the designed and measured data to analyze the boiler’s performance. After-combustion, the most significant phenomenon in low-density waste-derived fuel combustion in a CFBC boiler was monitored. The heat and mass balance were the most appropriate tools to analyze the boiler performance. The flow rate of spray water at the de-superheater was a reliable indicator to quantify the after-combustion. The design modification of the boiler unit for after-combustion control in the existing boiler was based on the quantification of spray water. The load distribution of the de-superheater decreases from 1.76% to 0.87% in 89% MCR before the installation of the evaporator and 82* % MCR load distribution of each boiler part after installation. The result was effective for the control of after-combustion in the existing boiler.

As people begin to notice mixed reality, various studies on user satisfaction in mixed reality (MR) have been conducted. User interface (UI) is one of the representative factors that affect interaction satisfaction in MR. In conventional platforms such as mobile devices and personal computers, various studies have been conducted on providing adaptive UI, and recently, such studies have also been conducted in MR environments. However, there have been few studies on providing an adaptive UI based on interaction satisfaction. Therefore, in this paper, we propose a method based on interaction-satisfaction prediction to provide an adaptive UI in MR. The proposed method predicts interaction satisfaction based on interaction information (gaze, hand, head, object) and provides an adaptive UI based on predicted interaction satisfaction. To develop the proposed method, an experiment to measure data was performed, and a user-satisfaction-prediction model was developed based on the data collected through the experiment. Next, to evaluate the proposed method, an adaptive UI providing an application using the developed user-satisfaction-prediction model was implemented. From the experimental results using the implemented application, it was confirmed that the proposed method could improve user satisfaction compared to the conventional method.

Neuroinflammation, which is mediated by microglia that release various inflammatory cytokines, is a typical feature of neurodegenerative diseases (NDDs), such as Alzheimer’s disease and Parkinson’s disease. Hence, alleviating neuroinflammation by downregulating pro-inflammatory action, and upregulating anti-inflammatory action of microglia is an efficient therapeutic target for NDDs. In this study, we evaluated whether trichosanthis semen (TS), a dried ripe seed of Trichosanthes kirilowii Maximowicz, reduces lipopolysaccharide (LPS)-induced neuroinflammation by regulating microglial responses in vitro and in vivo. Our results presented that TS reduced the release of pro-inflammatory mediators, such as nitric oxide (NO), inducible NO synthase, tumor necrosis factor-α, interleukin-1β, and interleukin-6 via inhibition of the nuclear factor kappa B (NF-κB) signaling pathway in LPS-treated BV2 microglial cells. Moreover, TS induced anti-inflammatory mediators, such as interleukin-10, found in inflammatory zone 1, and chitinase 3-like 3 by the upregulation of heme oxygenase 1 (HO-1). We further confirmed that TS administration suppressed microglial activation, but enhanced HO-1 expression in LPS-injected mice. These results suggest that TS has anti-neuroinflammatory effects via inhibition of NF-κB signaling through the activation of HO-1, and that TS may be a therapeutical candidate for NDDs treatment.

Various studies on latency in remote mixed reality collaborations (remote MR collaboration) have been conducted, but studies related to interaction latency are scarce. Interaction latency in a remote MR collaboration occurs because action detection (such as contact or collision) between a human and a virtual object is required for finding the interaction performed. Therefore, in this paper, we propose a method based on interaction prediction to reduce the time for detecting the action between humans and virtual objects. The proposed method predicts an interaction based on consecutive joint angles. To examine the effectiveness of the proposed method, an experiment was conducted and the results were given. From the experimental results, it was confirmed that the proposed method could reduce the interaction latency compared to the one obtained by conventional methods.

The authors wish to make the following correction to [...]

Extracellular vesicles (EVs) are paracrine factors that mediate stem cell therapeutics. We aimed at evaluating the possible therapeutic and esthetic applications of EVs prepared from the waste human facial tissue-derived orbicularis oculi muscle stem cells (OOM-SCs). OOM-SCs were isolated from the ocular tissues (from elders and youngsters) after upper eyelid blepharoplasty or epiblepharon surgeries. EVs were prepared from the OOM-SCs (OOM-SC-EVs) and their three-dimensional spheroids. OOM-SCs showed a spindle-like morphology with trilineage differentiation capacity, positive expression of CD105, CD 90, and CD73, and negative expression of CD45 and CD34, and their stem cell properties were compared with other adult mesenchymal stem cells. OOM-SC-EVs showed a high inhibitory effect on melanin synthesis in B16F10 cells by blocking tyrosinase activity. OOM-SC-EVs treatment led to a significant attenuation of senescence-associated changes, a decrease in reactive oxygen species generation, and an upregulation of antioxidant genes. We demonstrated the regeneration activity of OOM-SC-EVs in in vitro wound healing of normal human dermal fibroblasts and upregulation of anti-wrinkle-related genes and confirmed the therapeutic potential of OOM-SC-EVs in the healing of the in vivo wound model. Our study provides promising therapeutic and esthetic applications of OOM-SC-EVs, which can be obtained from the ocular surgery-derived waste human facial tissues.

Heat stress induces the hypothalamic-pituitary-adrenal (HPA) axis activation, influences biological responses, and reduces energy metabolism. Geongangbuja-tang (GBT) and its components, Zingiberis Rhizoma (ZOR) and Aconiti Lateralis Radix Preparata (ALRP) have been used to induce energy metabolism; however, the effects of GBT and its ingredients on heat-induced inflammatory responses have not yet been investigated. In this study, we performed an open-field test to evaluate locomotor activity in mice. To assess the effects of GBT and its ingredients on inflammation, the protein levels of c-fos, pro-inflammatory cytokines, and cortisol were measured in the mouse hypothalamus and serum. The results showed that GBT alleviated locomotive activity and reduced c-fos levels in a dose-dependent manner under the heat exposure. After investigating the active constituent of GBT, we found that compared to GBT and ZOR, ALRP significantly suppressed c-fos expression under heat stress. Subsequently, ALRP decreased the expression of pro-inflammatory cytokines, such as interleukin-9 and -13 and prostaglandin, under the heat stress in the mouse hypothalamus. Moreover, treatment with ALRP inhibited cortisol secretion in the mouse serum following heat exposure. These results indicate that GBT and its active component, ALRP, could be the thermoregulatory agents that regulate the HPA axis.

Although Electroacupuncture (EA) has been reported to be potentially effective for cognitive disorders, there is limited information about which domains of cognitive function can be improved by EA treatment. Sixty patients with MCI were randomly assigned (1:1:1) to groups to receive 24 sessions over 12 weeks of EA, sham EA, or usual care. In the EA group, electric stimulation was applied at bilateral PC6 and HT7. Various cognitive tests included in the Seoul Neuropsychological Screening Battery II (SNSB-II) were performed at baseline and post-treatment to explore effects of EA on five cognitive domains: attention, language, visuospatial function, memory, and frontal/executive function. Among 60 randomized participants (63.7 ± 7.1 years, 89.7% females), 45 (75%) completed the study. Of the five cognitive function domains of SNSB-II, the T score of visuospatial function showed a tendency to be higher in the EA group than in the usual care group at post-treatment assessment (mean difference: 10.16 (95% CI, 1.14, 19.18), Cohen’s d = 0.72, p = 0.0283). According to the results of this pilot study, the estimated effect size of EA on the visuospatial function of MCI patients compared to usual care was medium. Large-scale clinical trials are needed to confirm effects of EA on cognitive functions.