Predictors of Continuous Positive Airway Pressure Adherence and Comparison of Clinical Factors and Polysomnography Findings Between Compliant and Non-Compliant Korean Adults With Obstructive Sleep Apnea.

OBJECTIVE: Continuous positive airway pressure (CPAP) is the preferred treatment for obstructive sleep apnea (OSA). However, compliance with CPAP therapy varies among studies, and studies on its predictors are insufficient in Korea. This study aimed to identify factors that predict compliance with CPAP therapy in patients with OSA. METHODS: We retrospectively reviewed medical records, polysomnography (PSG) records, and self-report questionnaires of patients w ith OSA. Criteria for compliance was the use of CPAP devices for ≥4 h per night for ≥70% of the consecutive 30 nights (i.e., 21 days) during the first 3 months of treatment initiation. The patients were classified into two groups: compliant and non-compliant. Logistic regression analyses were performed to identify the clinical factors and PSG parameters associated with CPAP compliance. RESULTS: Of the 188 participants, 80 were classified into the compliant group and 108 into the non-compliant group. The ratios of stage N1 (p=0.011) and health insurance coverage (p=0.007) were significantly associated with compliance with CPAP, with an explanatory power of 18.6% (R2=0.186, p<0.001). CONCLUSION: Stage N1 ratio and health insurance coverage were significant predictors of CPAP compliance. It is necessary to confirm whether the relationship between a high stage N1 ratio and compliance can be reproduced in a larger sample and in individuals from other countries.

Genome-wide association analyses using machine learning-based phenotyping reveal genetic architecture of occupational creativity and overlap with psychiatric disorders.

Creativity is known to be heritable and exhibits familial aggregation with psychiatric disorders; however, the complex nature of their relationship has not been well-established. In the present study, we demonstrate that using an expanded and validated machine learning (ML)-based phenotyping of occupational creativity (OC) can allow us to further understand the trait of creativity, which was previously difficult to define and study. We conducted the largest genome-wide association study (GWAS) on OC with 241,736 participants from the UK Biobank and identified 25 lead variants that have not yet been reported and three candidate causal genes that were previously associated with educational attainment and psychiatric disorders. We found extensive genetic overlap between OC and psychiatric disorders with mixed effect direction through various post-GWAS analyses, including the bivariate causal mixture model. In addition, we discovered a strongly genetic correlation between our original GWAS and the GWAS adjusted for education years (rg = 0.95). Our GWAS analysis via ML-based phenotyping contributes to the understanding of the genetic architecture of creativity, which may inform genetic discovery and genetic prediction in human cognition and psychiatric disorders.

Leveraging genetic overlap between irritability and psychiatric disorders to identify genetic variants of major psychiatric disorders.

Irritability is a heritable core mental trait associated with several psychiatric illnesses. However, the genomic basis of irritability is unclear. Therefore, this study aimed to 1) identify the genetic variants associated with irritability and investigate the associated biological pathways, genes, and tissues as well as single-nucleotide polymorphism (SNP)-based heritability; 2) explore the relationships between irritability and various traits, including psychiatric disorders; and 3) identify additional and shared genetic variants for irritability and psychiatric disorders. We conducted a genome-wide association study (GWAS) using 379,506 European samples (105,975 cases and 273,531 controls) from the UK Biobank. We utilized various post-GWAS analyses, including linkage disequilibrium score regression, the bivariate causal mixture model (MiXeR), and conditional and conjunctional false discovery rate approaches. This GWAS identified 15 independent loci associated with irritability; the total SNP heritability estimate was 4.19%. Genetic correlations with psychiatric disorders were most pronounced for major depressive disorder (MDD) and bipolar II disorder (BD II). MiXeR analysis revealed polygenic overlap with schizophrenia (SCZ), bipolar I disorder (BD I), and MDD. Conditional false discovery rate analyses identified additional loci associated with SCZ (number [n] of additional SNPs = 105), BD I (n = 54), MDD (n = 107), and irritability (n = 157). Conjunctional false discovery rate analyses identified 85, 41, and 198 shared loci between irritability and SCZ, BD I, and MDD, respectively. Multiple genetic loci were associated with irritability and three main psychiatric disorders. Given that irritability is a cross-disorder trait, these findings may help to elucidate the genomics of psychiatric disorders.

Argyrodite configuration determination for DFT and AIMD calculations using an integrated optimization strategy.

When constructing a partially occupied model structure for use in density functional theory (DFT) and ab initio molecular dynamics (AIMD) calculations, the selection of appropriate configurations has been a vexing issue. Random sampling and the ensuing low-Coulomb-energy entry selection have been routine. Here, we report a more efficient way of selecting low-Coulomb-energy configurations for a representative solid electrolyte, Li6PS5Cl. Metaheuristics (genetic algorithm, particle swarm optimization, cuckoo search, and harmony search), Bayesian optimization, and modified deep Q-learning are utilized to search the large configurational space. Ten configuration candidates that exhibit relatively low Coulomb energy values and thereby lead to more convincing DFT and AIMD calculation results are pinpointed along with computational cost savings by the assistance of the above-described optimization algorithms, which constitute an integrated optimization strategy. Consequently, the integrated optimization strategy outperforms the conventional random sampling-based selection strategy.

Aux-MVNet: Auxiliary Classifier-Based Multi-View Convolutional Neural Network for Maxillary Sinusitis Diagnosis on Paranasal Sinuses View.

Computed tomography (CT) is undoubtedly the most reliable and the only method for accurate diagnosis of sinusitis, while X-ray has long been used as the first imaging technique for early detection of sinusitis symptoms. More importantly, radiography plays a key role in determining whether or not a CT examination should be performed for further evaluation. In order to simplify the diagnostic process of paranasal sinus view and moreover to avoid the use of CT scans which have disadvantages such as high radiation dose, high cost, and high time consumption, this paper proposed a multi-view CNN able to faithfully estimate the severity of sinusitis. In this study, a multi-view convolutional neural network (CNN) is proposed which is able to accurately estimate the severity of sinusitis by analyzing only radiographs consisting of Waters' view and Caldwell's view without the aid of CT scans. The proposed network is designed as a cascaded architecture, and can simultaneously provide decisions for maxillary sinus localization and sinusitis classification. We obtained an average area under the curve (AUC) of 0.722 for maxillary sinusitis classification, and an AUC of 0.750 and 0.700 for the left and right maxillary sinusitis, respectively, using the proposed network.

An Extremely Inexpensive, Simple, and Flexible Carbon Fiber Electrode for Tunable Elastomeric Piezo-Resistive Sensors and Devices Realized by LSTM RNN.

Here, we describe the utility of a carbon fiber (CF) electrode that is inexpensive, simple, and flexible and can be embedded with elastomeric nanocomposite piezo-resistive sensors fabricated from silicone rubber (Ecoflex) blended with carbon nanotubes (CNTs) and various wt % of silicone thinner to tune the sensitivity and softness range. The performance of the CF electrode was evaluated on the basis of piezo-resistive responses from the sensors subjected to dynamic sinusoidal compressive strains at different levels and frequencies. The responses were positive-pressure effects with rate-dependent asymmetric nonlinear hysteresis characteristics. Developing a mathematical model to describe the rate-dependent asymmetric nonlinear hysteresis behavior is technically impossible; therefore, we employed artificial intelligence-based hysteresis modeling, long short-term memory recurrent neural network, to describe the hysteresis nonlinearity. The debonding strength of the CF electrode was determined in the pull-off testing and was found to be much higher than that of a copper wire electrode. The debonding mechanism was further elucidated via an in situ resistance profile. The importance of a robust conductive interface between a CF electrode and a nanocomposite was experimentally demonstrated. It was found that the inherent piezo-resistance of the CF was negligible compared with the piezo-resistance of the sensor; therefore, the signals from the sensor were free of interference. We believe CF-embedded tunable piezo-resistive sensors could be used in biomedical devices, artificial e-skins, robotic touch applications, and flexible keyboards where the required stretchability of the electrode can be introduced via an appropriate geometrical design.

Deep-Learning Technique To Convert a Crude Piezoresistive Carbon Nanotube-Ecoflex Composite Sheet into a Smart, Portable, Disposable, and Extremely Flexible Keypad.

An extremely simple bulk sheet made of a piezoresistive carbon nanotube (CNT)-Ecoflex composite can act as a smart keypad that is portable, disposable, and flexible enough to be carried crushed inside the pocket of a pair of trousers. Both a rigid-button-imbedded, rollable (or foldable) pad and a patterned flexible pad have been introduced for use as portable keyboards. Herein, we suggest a bare, bulk, macroscale piezoresistive sheet as a replacement for these complex devices that are achievable only through high-cost fabrication processes such as patterning-based coating, printing, deposition, and mounting. A deep-learning technique based on deep neural networks (DNN) enables this extremely simple bulk sheet to play the role of a smart keypad without the use of complicated fabrication processes. To develop this keypad, instantaneous electrical resistance change was recorded at several locations on the edge of the sheet along with the exact information on the touch position and pressure for a huge number of random touches. The recorded data were used for training a DNN model that could eventually act as a brain for a simple sheet-type keypad. This simple sheet-type keypad worked perfectly and outperformed all of the existing portable keypads in terms of functionality, flexibility, disposability, and cost.

An extremely simple macroscale electronic skin realized by deep machine learning.

Complicated structures consisting of multi-layers with a multi-modal array of device components, i.e., so-called patterned multi-layers, and their corresponding circuit designs for signal readout and addressing are used to achieve a macroscale electronic skin (e-skin). In contrast to this common approach, we realized an extremely simple macroscale e-skin only by employing a single-layered piezoresistive MWCNT-PDMS composite film with neither nano-, micro-, nor macro-patterns. It is the deep machine learning that made it possible to let such a simple bulky material play the role of a smart sensory device. A deep neural network (DNN) enabled us to process electrical resistance change induced by applied pressure and thereby to instantaneously evaluate the pressure level and the exact position under pressure. The great potential of this revolutionary concept for the attainment of pressure-distribution sensing on a macroscale area could expand its use to not only e-skin applications but to other high-end applications such as touch panels, portable flexible keyboard, sign language interpreting globes, safety diagnosis of social infrastructures, and the diagnosis of motility and peristalsis disorders in the gastrointestinal tract.

Multi-functionalized herringbone carbon nanofiber for anodes of lithium ion batteries.

Herringbone carbon nanofibers (HCNFs) are prepared for use as anode materials in lithium-ion batteries (LIBs). HCNFs are prepared using a Ni-Fe catalyst and subsequently multi-functionalized with oxygen using the Hummers' method, and then with both oxygen and nitrogen-containing 2-ureido-4[1H]pyrimidinone (UHP) moieties, which endow the HCNFs with the ability to form quadruple hydrogen bonds (QHBs). The as-prepared HCNFs are, on average, 13 µm in length and 100 nm in diameter, with a highly graphitic structure. The oxidized HCNFs (Ox-HCNFs) obtained by Hummers' method are partially exfoliated, having double-bladed saw-like structures that extend in the direction of the graphite planes. QHBs are formed between the HCNFs after functionalization with the UHP moieties. The final surface-modified HCNFs (N-Ox-HCNFs) have more electrochemical sites, shorter Li+ diffusion lengths, and additional electron pathways compared with the as-prepared HCNF and Ox-HCNF. The introduction of oxygen- and nitrogen-containing functional groups improves the performance of LIBs: a high charge capacity of 763 mA h g-1 at 0.1 A g-1, excellent rate capability (a capacity of 402 mA h g-1 at 3 A g-1), and near 100% capacity retention after 300 cycles are reported.

Hysteresis compensation of photoluminescence in ZnS:Cu for noncontact shaft torque sensing.

This paper presents a preliminary investigation of loading rate-dependent hysteresis of photoluminescence (PL) by phosphorescence quenching of copper-doped zinc sulfide (ZnS:Cu) microparticles in response to dynamic torsional loading. Precision sinusoidal torque waveforms in the frequency range of 0.5-3 Hz are used to identify the loading rate-dependent (i.e., frequency-dependent) nonlinear hysteresis phenomenon. The potential of the application of PL is demonstrated by successfully measuring the sinusoidal torque applied to a rotational shaft by evaluating the loading rate-dependent PL intensity signature using a photomultiplier tube. In addition, the potential of noncontact shaft torque sensing is demonstrated successfully by the simple compensation derived from ad hoc heuristic characterization.

A smart load-sensing system using standardized mechano-luminescence measurement.

The mechano-luminescence (ML) of phosphors has stirred a great deal of interest for its potential application in inexpensive, non-destructive load sensors. However, the most serious drawback of ML phosphors has been responses that differ according to the loading conditions. This has led to a lack of standardization in realizing smart ML sensor applications. We improved the applicability of ML phosphors to that of a smart, standardized load sensor by detecting ML based on the UV excitation above the threshold power density during the entire loading process. The ML behavior under these conditions was completely different from that of conventional ML behavior with UV excitation turned off. The ML output was clearly represented as a simple linear function of the applied load under conditions that could be either static or dynamic. In addition, neither a ML loss angle nor hysteresis behavior was observed under these ML measurement conditions.

Effects of precursor concentrations and thermal annealing on ZnO nanorods grown by hydrothermal method.

ZnO nanorods were grown on spin-coated ZnO seed layers by hydrothermal method. The ZnO nanorods were grown with various precursor concentrations ranging from 0.01 to 0.3 M. Field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and photoluminescence (PL) were carried out to investigate the structural and optical properties of the ZnO nanorods. The average diameter and length of the ZnO nanorods is increased as the precursor concentration increased from 0.01 to 0.3 M. From XRD, the intensity of ZnO (002) peak is increased and full width at half maximum (FWHM) of ZnO (002) decreased as the precursor concentration increased. The FWHM of near-band-edge emission (NBE) decreased and intensity ratio of the NBE to the deep-level emission (DLE) increased as the precursor concentration increased which indicated the optical property is improved. The DLE is red-shifted from yellow- to red-emission and its intensity is increased as the annealing temperature increased due to thermal diffusion process.

Effects of thermal annealing in oxygen plasma for buffer layers on properties of ZnO thin films.

ZnO thin films with ZnO buffer layers were grown by plasma-assisted molecular beam epitaxy (PA-MBE) on p-type Si(100) substrates. Before the growth of the ZnO thin films, the ZnO buffer layers were deposited on the Si substrates for 20 minutes and then annealed at the different substrate temperature ranging from 600 to 800 degrees C in oxygen plasma. The structural and optical properties of the ZnO thin films have been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and room-temperature (RT) photoluminescence (PL). A narrower full width at half maximum (FWHM) of the XRD spectra for ZnO(002) and a larger grain are observed in the samples with the thermal annealed buffer layers in oxygen plasma, compared to those of the as-grown sample. The surface morphology of the samples is changed from rugged to flat surface. In the PL spectra, near-band edge emission (NBEE) at 3.2 eV (380 nm) and deep-level emission (DLE) around 1.77 to 2.75 eV (700 to 450 nm) are observed. By increasing the annealing temperatures up to 800 degrees C, the PL intensity of the NBEE peak is higher than that of the as-grown sample. These results imply that the structural and optical properties of ZnO thin films are improved by the annealing process.

Three-dimensional analysis of the tooth movement and arch dimension changes in Class I malocclusions treated with first premolar extractions: a guideline for virtual treatment planning.

INTRODUCTION: Our objective was to analyze patterns of tooth movement and changes of arch dimension by superimposing 3-dimensional (3D) virtual models. METHODS: The sample consisted of 24 Korean adults with Class I malocclusion and minimal crowding, treated by first premolar extractions, sliding mechanics (0.022-in MBT brackets [3M Unitek, Monrovia, Calif] with 0.019 × 0.025-in stainless steel wire) and moderate anchorage. The 3D virtual maxillary casts at pretreatment and posttreatment were superimposed with the best-fit method. Linear and angular variables were measured with 3Txer program (Orapix, Seoul, Korea). Wilcoxon signed rank and Mann-Whitney tests were used for statistical analysis. RESULTS: There was no significant difference in the individual tooth movement between the right and left sides (P > 0.05). For the movement of each tooth, the maxillary central incisors (U1), lateral incisors (U2), and canines (U3) were significantly inclined lingually, extruded, and moved posteriorly and laterally. The maxillary second premolar (U5), first molar (U6), and second molar (U7) had significant mesial inward rotation, anterior movement, and contracted toward the midsagittal plane. The ratio of anteroposterior movement between the maxillary anterior and posterior teeth was 5:1. The amounts of contraction in U5, U6, and U7 were 1.4, 1.3, and 1.2 mm, respectively. When the amount of change between the adjacent teeth were compared, the linguoversion in U1 was significantly greater than that of U2. U3 and U5 showed significant opposite movements in all variables. There were differences only in angulation and vertical displacement between U6 and U7. CONCLUSIONS: Superimposition of 3D virtual models could be a guideline for precise virtual treatment planning.

Laparoscopy-assisted exploration of obscure gastrointestinal bleeding after capsule endoscopy: the Korean experience.

BACKGROUND: Obscure gastrointestinal bleeding (OGB) is generally defined as recurrent acute or chronic bleeding for which no source has been identified by routine radiologic and endoscopic examination. The aim of this study was to report our early experiences detecting small bowel bleeding by capsule endoscopy (CE) and the results of laparoscopy assisted surgery for OGB. MATERIALS AND METHODS: Seventy-five patients with OGB were examined by CE. Twelve of 24 patients in the active bleeding group underwent laparoscopic or laparoscopy assisted surgery and we carried out intraoperative enteroscopy to find the focus of the bleeding. RESULTS: Laparoscopic localization of the lesion was successful for 4 patients-those with Meckel's diverticulum, gastrointestinal stromal tumor, lymphoma, and ischemic necrosis. In 3 cases in which there was no natural passage of the capsule endoscope, lesions were identified by small bowel exploration through simple palpation by hand. Intraoperative enteroscopy was performed extracorporeally in 5 cases through a minilaparotomy window using an extended incision of a port site less than 7 cm in length. The lesions that were identified by CE preoperatively were resected successfully, via laparoscopic or laparoscopy-assisted surgery. The gastrointestinal bleeding has not recurred during the postoperative follow-up period (mean, 10.6 months). CONCLUSION: The laparoscopic approach can be chosen for surgical management of OGB patients with active bleeding whose lesions have been identified by CE. This approach allows minimally invasive surgical treatment for ongoing OGB.

Fever of unknown origin as a presentation of gastric inflammatory myofibroblastic tumor in a two-year-old boy.

Gastric inflammatory myofibroblastic tumor (IMT) is an extremely rare lesion with mimicking malignant features and accompanied with various clinical manifestations. Here we present a 2-yr-old boy who had a gastric IMT with a huge extragastric mass, which closely resembled a neuroblastoma on imaging studies. He experienced intermittent fever and poor appetite for 6 weeks. Fever remained up to 38 degrees C even on the operation day. He underwent partial gastrectomy and distal pancreatectomy with splenectomy including the tumor. The preoperative fever disappeared and did not recur in the postoperative course.

Impact of splenectomy on circulating T-lymphocyte subsets in stage III gastric cancer.

BACKGROUND: The role of splenectomy remains unclear in patients with gastric cancer who undergo total gastrectomy. The aim of this study was to prospectively evaluate the impact of splenectomy on circulating T-lymphocyte subsets and survival in advanced gastric cancer. METHODS: Analysis of lymphocyte subsets was performed in 40 patients with American Joint Committee on Cancer (AJCC) stage III gastric adenocarcinoma located on the upper one-third of the stomach, who underwent a curative total gastrectomy with or without splenectomy. Circulating T-lymphocyte subsets were measured on venous blood by using flow cytometry and monoclonal antibodies at preoperative day 1, and postoperative months 1, 3, 6, 12 and 18. RESULTS: The proportion of lymphocytes and the values of CD3, CD8, CD16 and CD25 subsets were higher in the splenectomy group of patients at postoperative month 3. In the spleen preservation group at the same point of treatment, the proportion of granulocytes and the values of CD4 and CD4 : CD8 ratio were higher. Except for CD16 levels, all T-lymphocyte subsets showed no significant difference between splenectomy and spleen preservation groups after postoperative month 3. Increased CD16 levels in the splenectomy group were not associated with improvement in patients' 5-year survival rates. CONCLUSION: These results suggest that the long-term impact of splenectomy does not play an important role in postoperative quantitative changes of circulating T-lymphocyte subsets of patients with stage III gastric cancer who have undergone total gastrectomy. Furthermore, splenectomy does not give a prognostic benefit, based on tumour recurrence and survival of patients with proximal one-third gastric cancer who undergo total gastrectomy.

Effects of red ginseng upon postoperative immunity and survival in patients with stage III gastric cancer.

In this paper, we present evidence that the red ginseng powder from Panax ginseng C.A. Meyer inhibits the recurrence of AJCC stage III gastric cancer and shows immunomodulatory activities during postoperative chemotherapy, after a curative resection with D2 lymph node dissection. Flow cytometric analyses for peripheral T-lymphocyte subsets showed that the red ginseng powder restored CD4 levels to the initial preoperative values during postoperative chemotherapy. Depression of CD3 during postoperative chemotherapy was also inhibited by the red ginseng powder ingestion. This study demonstrated a five-year disease free survival and overall survival rate that was significantly higher in patients taking the red ginseng powder during postoperative chemotherapy versus control (68.2% versus 33.3%, 76.4% versus 38.5%, respectively, p < 0.05). In spite of the limitation of a small number of patients (n = 42), these findings suggest that red ginseng powder may help to improve postoperative survival in these patients. Additionally, red ginseng powder may have some immunomodulatory properties associated with CD3 and CD4 activity in patients with advanced gastric cancer during postoperative chemotherapy.