Deep Non-Line-of-Sight Imaging Using Echolocation.

Non-line-of-sight (NLOS) imaging is aimed at visualizing hidden scenes from an observer's (e.g., camera) viewpoint. Typically, hidden scenes are reconstructed using diffused signals that emit light sources using optical equipment and are reflected multiple times. Optical systems are commonly adopted in NLOS imaging because lasers can transport energy and focus light over long distances without loss. In contrast, we propose NLOS imaging using acoustic equipment inspired by echolocation. Existing acoustic NLOS is a computational method motivated by seismic imaging that analyzes the geometry of underground structures. However, this physical method is susceptible to noise and requires a clear signal, resulting in long data acquisition times. Therefore, we reduced the scan time by modifying the echoes to be collected simultaneously rather than sequentially. Then, we propose end-to-end deep-learning models to overcome the challenges of echoes interfering with each other. We designed three distinctive architectures: an encoder that extracts features by dividing multi-channel echoes into groups and merging them hierarchically, a generator that constructs an image of the hidden object, and a discriminator that compares the generated image with the ground-truth image. The proposed model successfully reconstructed the outline of the hidden objects.

Effect of abdominal drawing-in maneuver with prone hip extension on muscle activation of posterior oblique sling in normal adults.

[Purpose] There have been many studies on ipsilateral erector spinae in regard of prone hip extension (PHE). However, mediating methods have been focusing on the reinforcement of gluteus. Hereupon, this study is intended to identify how an increase of abdominal drawing-in maneuver influences on posterior oblique sling (POS) and suggest a mediating method to effectively reinforce them. [Participants and Methods] This study has been conducted on normal male (10) and female (10), and participants were asked to prove PHE exercise and abdominal drawing-in maneuver prone hip extension exercise (ADIM PHE). Surface electromyography (EMG) was recorded from the contralateral latissimus dorsi, ipsilateral erector spinae, ipsilateral gluteus maximus, and ipsilateral biceps femoris. A pared t-test was used to compare muscle activity POS. [Results] EMG activity of the contralateral latissimus dorsi, ipsilateral gluteus maximus was significantly greater performed ADIM PHE than PHE. As for ipsilateral erector spinae muscle, ipsilateral biceps femoris activation was lower in ADIM PHE than PHE. [Conclusion] According to the results of this study, abdominal drawing-in maneuver seems to be an important factor that influences on muscular activation of POS.

Giant coercivity enhancement in a room-temperature van der Waals magnet through substitutional metal-doping.

FexGeTe2 (x = 3, 4, and 5) systems, two-dimensional (2D) van der Waals (vdW) ferromagnetic (FM) metals with high Curie temperatures (TC), have been intensively studied to realize all-2D spintronic devices. Recently, an intrinsic FM material Fe3GaTe2 with high TC (350-380 K) has been reported. As substitutional doping changes the magnetic properties of vdW magnets, it can be a powerful means for engineering the properties of magnetic materials. Here, the coercive field (Hc) is substantially enhanced by substituting Ni for Fe in (Fe1-xNix)3GaTe2 crystals. The introduction of a Ni dopant with x = 0.03 can enhance the value of Hc up to ∼200% while maintaining the FM state at room temperature. As the doping level increases, TC decreases, whereas Hc increases up to 7 kOe at x = 0.12, which is the highest Hc reported so far. The FM characteristic is almost suppressed at x = 0.68 and a spin glass state appears. The enhancement of Hc resulting from Ni doping can be attributed to domain pinning induced by substitutional Ni atoms, as evidenced by the decrease in magnetic anisotropy energy in the crystals upon Ni doping. Our findings provide a highly effective way to control the Hc of the 2D vdW FM metal Fe3GaTe2 for the realization of Fe3GaTe2 based room-temperature operating spintronic devices.

Clustering and prediction of long-term functional recovery patterns in first-time stroke patients.

Objectives: The purpose of this study was to cluster long-term multifaceted functional recovery patterns and to establish prediction models for functional outcome in first-time stroke patients using unsupervised machine learning. Methods: This study is an interim analysis of the dataset from the Korean Stroke Cohort for Functioning and Rehabilitation (KOSCO), a long-term, prospective, multicenter cohort study of first-time stroke patients. The KOSCO screened 10,636 first-time stroke patients admitted to nine representative hospitals in Korea during a three-year recruitment period, and 7,858 patients agreed to enroll. Early clinical and demographic features of stroke patients and six multifaceted functional assessment scores measured from 7 days to 24 months after stroke onset were used as input variables. K-means clustering analysis was performed, and prediction models were generated and validated using machine learning. Results: A total of 5,534 stroke patients (4,388 ischemic and 1,146 hemorrhagic; mean age 63·31 ± 12·86; 3,253 [58.78%] male) completed functional assessments 24 months after stroke onset. Through K-means clustering, ischemic stroke (IS) patients were clustered into five groups and hemorrhagic stroke (HS) patients into four groups. Each cluster had distinct clinical characteristics and functional recovery patterns. The final prediction models for IS and HS patients achieved relatively high prediction accuracies of 0.926 and 0.887, respectively. Conclusions: The longitudinal, multi-dimensional, functional assessment data of first-time stroke patients were successfully clustered, and the prediction models showed relatively good accuracies. Early identification and prediction of long-term functional outcomes will help clinicians develop customized treatment strategies.

A Multicenter Randomized Controlled Trial To Evaluate the Efficacy and Safety of Nelfinavir in Patients with Mild COVID-19.

Nelfinavir, an orally administered inhibitor of human immunodeficiency virus protease, inhibits the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro. We conducted a randomized controlled trial to evaluate the clinical efficacy and safety of nelfinavir in patients with SARS-CoV-2 infection. We included unvaccinated asymptomatic or mildly symptomatic adult patients who tested positive for SARS-CoV-2 infection within 3 days before enrollment. The patients were randomly assigned (1:1) to receive oral nelfinavir (750 mg; thrice daily for 14 days) combined with standard-of-care or standard-of-care alone. The primary endpoint was the time to viral clearance, confirmed using quantitative reverse-transcription PCR by assessors blinded to the assigned treatment. A total of 123 patients (63 in the nelfinavir group and 60 in the control group) were included. The median time to viral clearance was 8.0 (95% confidence interval [CI], 7.0 to 12.0) days in the nelfinavir group and 8.0 (95% CI, 7.0 to 10.0) days in the control group, with no significant difference between the treatment groups (hazard ratio, 0.815; 95% CI, 0.563 to 1.182; P = 0.1870). Adverse events were reported in 47 (74.6%) and 20 (33.3%) patients in the nelfinavir and control groups, respectively. The most common adverse event in the nelfinavir group was diarrhea (49.2%). Nelfinavir did not reduce the time to viral clearance in this setting. Our findings indicate that nelfinavir should not be recommended in asymptomatic or mildly symptomatic patients infected with SARS-CoV-2. The study is registered with the Japan Registry of Clinical Trials (jRCT2071200023). IMPORTANCE The anti-HIV drug nelfinavir suppresses the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro. However, its efficacy in patients with COVID-19 has not been studied. We conducted a multicenter, randomized controlled trial to evaluate the efficacy and safety of orally administered nelfinavir in patients with asymptomatic or mildly symptomatic COVID-19. Compared to standard-of-care alone, nelfinavir (750 mg, thrice daily) did not reduce the time to viral clearance, viral load, or the time to resolution of symptoms. More patients had adverse events in the nelfinavir group than in the control group (74.6% [47/63 patients] versus 33.3% [20/60 patients]). Our clinical study provides evidence that nelfinavir, despite its antiviral effects on SARS-CoV-2 in vitro, should not be recommended for the treatment of patients with COVID-19 having no or mild symptoms.

Improvement of the tool life of a micro-end mill using nano-sized SiC/Ni electroplating method.

High mechanical properties of a tungsten carbide micro-end-mill tool was achieved by extending its tool life by electroplating nano-sized SiC particles (< 100 nm) that had a hardness similar to diamond in a nickel-based material. The co-electroplating method on the surface of the micro-end-mill tool was applied using SiC particles and Ni particles. Organic additives (saccharin and ammonium chloride) were added in a Watts bath to improve the nickel matrix density in the electroplating bath and to smooth the surface of the co-electroplating. The morphology of the coated nano-sized SiC particles and the composition were measured using Scanning Electron Microscope and Energy Dispersive Spectrometer. As the Ni/SiC co-electroplating layer was applied, the hardness and friction coefficient improved by 50%. Nano-sized SiC particles with 7 wt% were deposited on the surface of the micro-end mill while the Ni matrix was smoothed by adding organic additives. The tool life of the Ni/SiC co-electroplating coating on the micro-end mill was at least 25% longer than that of the existing micro-end mills without Ni/SiC co-electroplating. Thus, nano-sized SiC/Ni coating by electroplating significantly improves the mechanical properties of tungsten carbide micro-end mills.

Fabrication of dye-sensitized solar cell (DSSC) using different particle sizes of TiO2 deposited via nano-particle deposition system (NPDS).

TiO2 layers were fabricated using a nano-particle deposition system (NPDS) on transparent conductive oxide (TCO) glass for dye sensitized solar cells (DSSCs). Conventionally, TiO2 paste for working electrodes has been fabricated using paste type methods. The fabricated paste composed of a mixture of nano-sized TiO2 powders, binders and solutions is then painted on TCO glass. After drying, the TiO2 layer on TCO glass is sintered to make a path for electron transfer. TiO2 layers formed by this paste type method require numerous steps, which can be time consuming. In this study, TiO2 powders were sprayed directly on TCO glass using NPDS in order to simplify the fabrication steps. To improve porosity and produce scattering layers, commercial nanocrystalline TiO, powders with different sizes were alternately deposited. Moreover, powders with different sizes were mixed and deposited on the TCO glass. The results indicate that the DSSCs with a TiO2 layer composed of different particle sizes had better cell performance than the cells assembled with single-sized TiO2 particles. Therefore, this study shows that a dry TiO2 coating process is possible for DSSC fabrication to improve its cell efficiencies, and this method can easily be applied on flexible substrates since NPDS is a room-temperature deposition process.

Dry-spray deposition of TiO2 for a flexible dye-sensitized solar cell (DSSC) using a nanoparticle deposition system (NPDS).

TiO2 powders were deposited on indium tin oxide (ITO) coated polyethylene terephthalate (PET) substrates for application to the photoelectrode of a dye-sensitized solar cell (DSSC). In the conventional DSSC manufacturing process, a semiconductor oxide such as TiO2 powder requires a sintering process at higher temperature than the glass transition temperature (T(g)) of polymers, and thus utilization of flexible polymer substrates in DSSC research has been constrained. To overcome this restriction related to sintering, we used a nanoparticle deposition system (NPDS) that could produce a thin coating layer through a dry-spray method under atmospheric pressure at room temperature. The powder was sprayed through a slit-type nozzle having a 0.4 x 10 mm2 rectangular outlet. In order to determine the deposited TiO2 thickness, five kinds of TiO2 layered specimens were prepared, where the specimens have single and double layer structures. Deposited powders on the ITO coated PET substrates were observed using FE-SEM and a scan profiler The thicker TiO2 photoelectrode with a DSSC having a double layer structure showed higher energy efficiency than the single layer case. The highest fabricated flexible DSSC displayed a short circuit current density J(sc) = 1.99 mA cm(-2), open circuit voltage V(oc) = 0.71 V, and energy efficiency eta = 0.94%. These results demonstrate the possibility of utilizing the dry-spray method to fabricate a TiO2 layer on flexible polymer substrates at room temperature under atmospheric pressure.

First-principles study on structural, electronic, magnetic and thermodynamic properties of lithium ferrite LiFe5O8.

Lithium ferrite, LiFe5O8 (LFO), has attracted great attention for various applications, and there has been extensive experimental studies on its material properties and applications. However, no systematic theoretical study has yet been reported, so understanding of its material properties at the atomic scale is still required. In this work, we present a comprehensive investigation into the structural, electronic, magnetic and thermodynamic properties of LFO using first-principles calculations. We demonstrate that the ordered α-phase with ferrimagnetic spin configuration is energetically favourable among various crystalline phases with different magnetic configurations. By applying the DFT + U approach with U = 4 eV, we reproduce the lattice constant, band gap energy, and total magnetization in good agreement with experiments, emphasizing the importance of considering strong correlation and spin-polarization effects originating from the 3d states of Fe atoms. We calculated the phonon dispersions of LFO with ferrimagnetic and non-magnetic states, and subsequently evaluated the Gibbs free energy differences between the two states, plotting the P-T diagram for thermodynamic stability of the ferrimagnetic against non-magnetic state. From the P-T diagram, the Curie temperature is found to be ∼925 K at the normal condition and gradually increase with increasing pressure. Our calculations explain the experimental observations for material properties of LFO, providing a comprehensive understanding of the underlying mechanism and useful guidance for enhancing performance of LFO-based devices.

Factors Associated with COVID-19 Vaccine Booster Hesitancy: A Retrospective Cohort Study, Fukushima Vaccination Community Survey.

This was a retrospective cohort study, which aimed to investigate the factors associated with hesitancy to receive a third dose of a coronavirus disease 2019 (COVID-19) vaccine. A paper-based questionnaire survey was administered to all participants. This study included participants who provided answers in the questionnaire about whether they had an intent to receive a third dose of a vaccine. Data on sex, age, area of residence, adverse reactions after the second vaccination, whether the third vaccination was desired, and reasons to accept or hesitate over the booster vaccination were retrieved. Among the 2439 participants, with a mean (±SD) age of 52.6 ± 18.9 years, and a median IgG-S antibody titer of 324.9 (AU/mL), 97.9% of participants indicated their intent to accept a third vaccination dose. The logistic regression revealed that participants of a younger age (OR = 0.98; 95% CI: 0.96-1.00) and with a higher antibody level (OR = 2.52; 95% CI: 1.27-4.99) were positively associated with hesitancy over the third vaccine. The efficacy of the COVID-19 vaccine and concerns about adverse reactions had a significant impact on behavior regarding the third vaccination. A rapid increase in the booster dose rate is needed to control the pandemic, and specific approaches should be taken with these groups that are likely to hesitate over the third vaccine, subsequently increasing booster contact rate.

Time Course of Odor Categorization Processing.

The brain's mechanisms for categorizing different odors have long been a research focus. Previous studies suggest that odor categorization may involve multiple neurological processes within the brain with temporal and spatial neuronal activation. However, there is limited evidence regarding temporally mediated mechanisms in humans, especially millisecond odor processing. Such mechanisms may be important because different brain areas may play different roles at a particular activation time during sensory processing. Here, we focused on how the brain categorizes odors at specific time intervals. Using multivariate electroencephalography (EEG) analysis, we found that similarly perceived odors induced similar EEG signals during 50-100, 150-200, and 350-400 ms at the theta frequency. We also found significant activation at 100-150 and 350-400 ms at the gamma frequency. At these two frequencies, significant activation was observed in some olfactory-associated areas, including the orbitofrontal cortex. Our findings provide essential evidence that specific periods may be related to odor quality processing during central olfactory processing.

Refined prefrontal working memory network as a neuromarker for Alzheimer's disease.

Detecting Alzheimer's disease (AD) is an important step in preventing pathological brain damage. Working memory (WM)-related network modulation can be a pathological feature of AD, but is usually modulated by untargeted cognitive processes and individual variance, resulting in the concealment of this key information. Therefore, in this study, we comprehensively investigated a new neuromarker, named "refined network," in a prefrontal cortex (PFC) that revealed the pathological features of AD. A refined network was acquired by removing unnecessary variance from the WM-related network. By using a functional near-infrared spectroscopy (fNIRS) device, we evaluated the reliability of the refined network, which was identified from the three groups classified by AD progression: healthy people (N=31), mild cognitive impairment (N=11), and patients with AD (N=18). As a result, we identified edges with significant correlations between cognitive functions and groups in the dorsolateral PFC. Moreover, the refined network achieved a significantly correlating metric with neuropsychological test scores, and a remarkable three-class classification accuracy (95.0%). These results implicate the refined PFC WM-related network as a powerful neuromarker for AD screening.

A nanopore structured high performance toluene gas sensor made by nanoimprinting method.

Toluene gas was successfully measured at room temperature using a device microfabricated by a nanoimprinting method. A highly uniform nanoporous thin film was produced with a dense array of titania (TiO(2)) pores with a diameter of 70 ≈ 80 nm using this method. This thin film had a Pd/TiO(2) nanoporous/SiO(2)/Si MIS layered structure with Pd-TiO(2) as the catalytic sensing layer. The nanoimprinting method was useful in expanding the TiO(2) surface area by about 30%, as confirmed using AFM and SEM imaging. The measured toluene concentrations ranged from 50 ppm to 200 ppm. The toluene was easily detected by changing the Pd/TiO(2) interface work function, resulting in a change in the I-V characteristics.

Odor habituation can modulate very early olfactory event-related potential.

Odor habituation is a phenomenon that after repeated exposure to an odor, is characterized by decreased responses to it. The central nervous system is involved in odor habituation. To study odor habituation in humans, measurement of event-related potentials (ERPs) has been widely used in the olfactory system and other sensory systems, because of their high temporal resolution. Most previous odor habituation studies have measured the olfactory ERPs of (200-800) ms. However, several studies have shown that the odor signal is processed in the central nervous system earlier than at 200 ms. For these reasons, we studied whether when odors were habituated, olfactory ERP within 200 ms of odors could change. To this end, we performed an odor habituation behavior test and electroencephalogram experiments. In the behavior test, under habituation conditions, odor intensity was significantly decreased. We found significant differences in the negative and positive potentials within 200 ms across the conditions, which correlated significantly with the results of the behavior test. We also observed that ERP latency depended on the conditions. Our study suggests that odor habituation can involve the olfactory ERP of odors within 200 ms in the brain.

EEG Revealed That Fragrances Positively Affect Menopausal Symptoms in Mid-life Women.

During mid-life, women experienced not only physical but also neurological transition. Because of this, many women suffer from physiological and/or psychological menopausal symptoms. Although hormone therapy (HT) was broadly used to alleviate menopausal symptoms, HT showed inconsistent effects in case of psychological symptoms. Moreover, mid-life women's brains have distinct characteristics than in other periods of life, it is needed to study psychological symptoms in shifted brain network of mid-life women. As an alternative, inhalation of fragrances may alleviate psychological menopausal symptoms. To characterize the alleviation mechanism by fragrances, we tested the effect of fragrances on menopausal symptoms using electroencephalographic (EEG) methods. We hypothesized that fragrance could restore mid-life women's brain response to stressful situations. We tested six fragrance conditions, including no-odor condition (solvent only) in twenty-eight mid-life women (49.75 years±3.49). Our results showed that fragrances increased alpha power and decreased ß/α ratio depending on the severity of menopausal symptoms in a stressful situation. Our study would be helpful in psychological menopausal symptom alleviation as well as fragrance screening for well-being in mid-life.

Manufacturing of size controlled a-Si:H nanoparticles in plasma using pulsed hydrogen gas.

We synthesized size controlled a-Si:H nanoparticles in plasma using a hydrogen gas pulse. An inductively-coupled plasma chamber with RF power (13.56 MHz) was designed for this study. Experiments were performed with various hydrogen pulse ON-times ranging between 0.1 to 0.9 seconds for 1 second periods. The size of the synthesized nanoparticles was measured and analyzed using electron microscopy, Scanning Mobility Particle Sizer (SMPS) and Image J software. We observed that the size of a-Si:H nanoparticles decreased when the hydrogen pulse ON-time was increased. The a-Si:H nanoparticles were found to be spherical in shape and uniform. For hydrogen pulse ON-time greater than 0.3 second, we observed agglomerated particles due to an increase in their concentration. We hope that these particles can be used as an alternative anode material for lithium ion secondary batteries.

Single-walled carbon nanotube sensor monitoring the dissociation of argon gas.

Monitoring of argon gas dissociation was demonstrated using a matted sheet of single-walled carbon nanotubes (SWNTs), prepared by alternating current dielectrophoresis. The conductance of the SWNT network increased upon exposure to dissociated byproducts induced by corona discharge (CD), and the sensor signal was recovered rapidly by purging with the pure argon. Similar experiments on argon plasma were also carried out to investigate the applicability of the SWNT sensor in the monitoring of plasma-induced dissociation. The transduction mechanisms in both CD activity and plasma were analyzed using Raman spectroscopy. The results show that the detection of argon dissociation generated inside the reaction zone is possible using a miniaturized SWNT sensor.

Antidepressant-Like Effects of Vaccinium bracteatum in Chronic Restraint Stress Mice: Functional Actions and Mechanism Explorations.

The fruit of Vaccinium bracteatum Thunb. (VBF) is commonly known as the oriental blueberry in Korea. The aim of this study was to evaluate the antidepressant-like effects of water VBF extract (VBFW) in a mouse model of chronic restraint stress (CRS) and to identify the underlying mechanisms of its action. The behavioral effects of VBFW were assessed in the forced swim test (FST) and open field test (OFT). The levels of serum corticosterone (CORT), brain monoamines, in addition to the extracellular signal-regulated kinases (ERKs)/protein kinase B (Akt) signaling pathway were evaluated. VBFW treatment significantly reduced the immobility time and increased swimming time in FST without altering the locomotor activity in unstressed mice. Furthermore, CRS mice treated with VBFW exhibited a significantly decreased immobility time in FST and serum CORT, increased locomotor activity in OFT, and enhanced brain monoamine neurotransmitters. Similarly, VBFW significantly upregulated the ERKs/Akt signaling pathway in the hippocampus and PFC. In addition, VBFW may reverse CORT-induced cell death by enhancing cyclic AMP-responsive element-binding protein expression through the up-regulation of ERKs/Akt signaling pathways. In addition, VBFW showed the strong antagonistic effect of the 5-HT[Formula: see text] receptor by inhibiting 5-HT-induced intracellular Ca[Formula: see text] and ERK1/2 phosphorylation. Our study provides evidence that antidepressant-like effects of VBFW might be mediated by the regulation of monoaminergic systems and glucocorticoids, which is possibly associated with neuroprotective effects and antagonism of 5-HT[Formula: see text] receptor.

All Ink-Jet Printed P3HT:PCBM Organic Solar Cells on ITO-Coated Glass Substrate.

Printed electronics have surfaced with a lot of interest recently. This paper reports development of a non vacuum process for fabricating poly(3-hexylthiophene):[6,6]-pheny-C61-butyric acid methyl ester organic solar cells (OSCs) using ink-jet printing technique. The printing conditions of different layers were optimized to avoid the coffee ring effect and the Marangoni effect. The effect of substrate's temperature and drop spacing size was compared to obtain uniform layers. We controlled the substrate temperature ranging from 30 degrees C to 80 degrees C and varied the spacing size between two lines ranging from 10 µm to 80 µm during printing. The device characteristics were analyzed using alpha step and solar simulator. The optimized printed conditions for ZnO are 50 degrees C substrate temperature and 50 µm spacing size. For the active layer, PEDOT: PSS and Ag electrode, the optimized conditions are 50 degrees C/50 µm, 30 degrees C/30 µm and 80 degrees C/80 µm, respectively. The power conversion efficiency of the OSCs fabricated with optimized printing condition is 1.25%.

Low-Temperature Synthesis of Large-Scale Molybdenum Disulfide Thin Films Directly on a Plastic Substrate Using Plasma-Enhanced Chemical Vapor Deposition.

By plasma-enhanced chemical vapor deposition, a molybdenum disulfide (MoS2 ) thin film is synthesized directly on a wafer-scale plastic substrate at below 300 °C. The carrier mobility of the films is 3.74 cm(2) V(-1) s(-1) . Also, humidity is successfully detected with MoS2 -based sensors fabricated on the flexible substrate, which reveals its potential for flexible sensing devices.