Background: An imbalance in energy intake and expenditure can cause obesity, which is a major risk factor for chronic diseases such as heart disease, type 2 diabetes, insulin resistance, cancers and hyperlipidemia.Methods and Results: In this study, we evaluated the anti-obesity effects of a water extract from the young leaves of barley sprout (BS) in 3T3-L1 cells and in high-fat diet (HFD)-induced obese mice (HF). Lipid accumulation measurement indicates that BS markedly inhibited adipogenesis by reducing lipid droplet production in a dose-dependent manner. Furthermore, the mRNA expression of adipogenic transcription factors peroxisome proliferator-activated receptor-γ and fatty acid synthetase, CCAAT/enhancer binding protein-α and fatty acid binding protein 4 in 3T3-L1 cells was significantly inhibited by BS treatment. In an in vivo test, the BSadministered group of HFD-induced mice showed less body weight gain, and lower liver and epididymal white adipose tissue weights. The BS-treated mice showed decreased serum levels of leptin and lipids compared to untreated HFD mice and the levels of adiponectin and the HDL-cholesterol/total cholesterol ratio increased. These results indicate that BS inhibits body fat accumulation by reducing the mRNA expression of lipogenesis transcription factors and increasing serum adipokine concentration in in vitro and in vivo tests.Conclusions: BS reduced high fat diet-induced weight gain and had a positive effect on dyslipidemia.
This study investigated whether shear wave elastography (SWE) could be used to estimate the chronicity of supraspinatus tendon (SST) tears.A retrospective study was performed. From November 2015 to July 2016, 113 patients (52 men, 61 women; age range, 21 to 79 years) with persistent shoulder pain underwent 119 rotator cuff tendon examinations by routine B-mode ultrasonography, while SST elasticity was measured using SWE. Following the exclusion of eight suboptimal examinations, four examinations with missing SST measurements, and 27 examinations of patients with other conditions, 80 examinations were analyzed. A torn SST was found in 54 examinations (27 with a partial-thickness tear and 27 with a full-thickness tear). Elasticity values were compared in multiple ways. The results were analyzed using the Mann-Whitney U test or Kruskal-Wallis test.No statistically significant difference in elasticity values (in kPa) was found between normal (median, 94.65; interquartile range [IQR], 87.43 to 105.47) and torn SSTs (median, 96.79; IQR, 86.71 to 108.56) or between full-thickness tears (median, 93.80; IQR, 82.50 to 108.33) and partial-thickness tears (median, 96.83; IQR, 90.60 to 112.20). However, there was a statistically significant difference in elasticity according to whether the duration of symptoms was 1 year or less (median, 92.20; IQR, 84.01 to 104.38) or longer than 1 year (median, 105.10; IQR, 100.41 to 116.03; P=0.032).Elasticity values were significantly higher in torn SSTs in patients with chronic shoulder pain that had persisted for more than 1 year. Further studies with larger samples seem warranted to determine whether elasticity values measured by SWE can be used preoperatively as a surrogate marker of the chronicity of a rotator cuff tendon tear.
Rheumatoid nodules are the most common extra-articular presentations of rheumatoid arthritis. Although rheumatoid nodules can develop anywhere in the body, they develop most commonly in the subcutaneous region, where they are easily exposed to repetitive trauma or pressure. However, an infrascapular presentation has not yet been reported. We report a case of giant bilateral rheumatoid nodules that developed in the infrascapular area, complicating its distinction from elastofibroma dorsi on radiological examination.류마티스 결절은 류마티스관절염의 가장 흔한 관절 외 증상이다. 류마티스 결절은 우리 몸의 어느 곳에서나 발생할 수 있지만 반복적인 외상이나 압력에 쉽게 노출되는 피하 부위에서 가장 흔하게 발생한다. 그러나 견갑하부에 자란 류마티스 결절은 보고된 바가 없었고, 이에 저자는 배부 탄성섬유종과 영상의학적으로 구분이 어려웠던 견갑하부에 발생한 류마티스 결절의 사례를 보고하고자 한다.
Abstract Objectives To determine the risk factors for mortality in Korean patients with rheumatoid arthritis (RA)-associated interstitial lung disease (ILD) in comparison to patients with RA but without ILD (RA-nonILD). Methods Data were extracted from a single-centre prospective cohort of RA patients with a chest computed tomography scan at an academic referral hospital in Korea. Patients with RA-ILD enroled between May 2017 and August 2022 were selected, and those without ILD were selected as comparators. The mortality rate was calculated, and the causes of each death were investigated. We used Cox proportional hazard regression with Firth’s penalised likelihood method to identify the risk factors for mortality in patients with RA-ILD. Results A total of 615 RA patients were included: 200 with ILD and 415 without ILD. In the RA-ILD group, there were 15 deaths over 540.1 person-years (PYs), resulting in mortality rate of 2.78/100 PYs. No deaths were reported in the RA-nonILD group during the 1669.9 PYs. The primary causes of death were infection (nine cases) and lung cancer (five cases), with only one death attributed to ILD aggravation. High RA activity (adjusted HR 1.87, CI 1.16–3.10), baseline diffusing capacity for carbon monoxide (DLCO) < 60% (adjusted HR 4.88, 95% CI 1.11–45.94), and usual interstitial pneumonia (UIP) pattern (adjusted HR 5.13, 95% CI 1.00–57.36) were identified as risk factors for mortality in RA-ILD patients. Conclusion Patients with RA-ILD have an elevated risk of mortality compared with those without ILD. Infection-related deaths are the main causes of mortality in this population. High RA activity, low DLCO, and the UIP pattern are significantly associated with the mortality in patients with RA-ILD.
The hydraulic solenoid valve is an essential electromechanical component used in various industries to control the flow rate, pressure, and direction of hydraulic fluid. However, these valves can fail due to factors like electrical issues, mechanical wear, contamination, seal failure, or improper assembly; these failures can lead to system downtime and safety risks. To address hydraulic solenoid valve failure, and its related impacts, this study aimed to develop a nondestructive diagnostic technology for rapid and accurate diagnosis of valve failures. The proposed approach is based on a data-driven model that uses voltage and current signals measured from normal and faulty valve samples. The algorithm utilizes a convolutional autoencoder and hypersphere-based clustering of the latent variables. This clustering approach helps to identify patterns and categorize the samples into distinct groups, normal and faulty. By clustering the data into groups of hyperspheres, the algorithm identifies the specific fault type, including both known and potentially new fault types. The proposed diagnostic model successfully achieved an accuracy rate of 98% in classifying the measurement data, which were augmented with white noise across seven distinct fault modes. This high accuracy demonstrates the effectiveness of the proposed diagnosis method for accurate and prompt identification of faults present in actual hydraulic solenoid valves.
The hydraulic system of an excavator consists of a central hydraulic power source and multiple actuator circuits. The numerical stiffness of the hydraulic system model, the complex hydraulic circuits of the excavator, and the coupling of the dynamics associated with the hydraulic system and mechanical manipulator have been major barriers to developing a real-time simulation. This article presents a coupled dynamic model of a large-sized excavator and a real-time simulation environment. A modeling approach for simulation speed while maintaining the essential features of the hydraulic system is described. The hydraulic circuit models are coded using the MathWorks Simscape Language that gives flexibilities for modeling and modularization. To make the simulation real-time capable and accurate, the entire model is divided into multiple sub-models for parallel execution, a local stiff integration solver is applied to the hydraulic sub-models, and a deliberately devised execution order is assigned to the groups of sub-models. The simulation results show good correspondence with the test results.
본 논문에서는 수중에서 운용하는 임베디드 능동 음향탐지 시스템에 적용하기 위한 광대역 송신 전력 증폭기 설계/제작/시험 과정에서 발생된 문제를 분석하고 해결방안을 제시한다. 최근 수중음향 분야에서도 탐지 성능을 향상시키기 위해 광대역 소나(Sound Navigation and Ranging, SONAR) 신호처리 연구가 진행되고 있으며 이를 위한 광대역 수중음향 송수신 장치 개발이 이루어지고 있다. 본 논문에서는 임베디드 시스템 특성상 복잡하지 않고 구현이 간단한 2 레벨 톱니파 형태의 Class D 급 PWM(Pulse Width Modulation) 신호 생성 방식을 사용하여 광대역 수중음향 신호를 생성한 이후에, 송신 증폭기를 통하여 다양한 형태의 송신 파형을 재생하고 수중에서 실험을 하는 과정에서 두가지 이상의 주파수를 가진 소나 신호를 동시에 재생한 경우, 원신호에 두 신호의 주파수 차의 정수배만큼 더해진 기생 주파수가 나타나는 현상이 발생하여 원하지 않은 송신 음원이 재생되는 문제가 있음을 발견하였다. 이러한 문제점의 원인을 분석하기 위해 MATLAB 및 Simulink를 이용하여 송신 하드웨어 및 PWM 제어 과정을 모델링하고 시뮬레이션 하였으며, 시뮬레이션을 통해 문제점을 재현하고 해결방안을 제시한다. The problem that occurred in the design/fabrication/testing of the wideband transmitting power amplifier for an embedded active SONAR (Sound Navigation and Ranging) system operating underwater was analyzed and the solution of the problem was proposed in this paper. Wideband acoustic SONAR systems had been developed in order to improve the underwater detection performance. The underwater acoustic transmission system had been also developed to achieve the wideband SONAR system. In this paper, the wideband acoustic transmission signal was generated using a 2 Level sawtooth type Class D PWM (Pulse Width Modulation) which was not complicated to implement. When the sonar signals having two or more frequencies were simultaneously generated, parasitic frequencies were added to the original signals by integer multiples of the frequency difference of the original signal. To cope with this problem, we proposed a way to remove the parasitic frequency from the source signal through modeling and simulation of the implemented power amplifier and PWM control hardware using MATLAB and Simulink.
이륜차용 셀프밸런싱 기술은 정지 및 저속 주행 중에도 이륜차가 옆으로 넘어지지 않도록 능동적으로 균형을 잡아주는 기술로서 이륜차의 운전 편의성과 사고 시 안전성을 높여주는 기술이다. 셀프밸런싱 기술은 최근 연구되고 있는 이륜차용 무인운전 및 자율주행 기술의 구현에 있어서도 기반이 되는 중요한 기술로서 본 논문은 제어모멘트자이로를 전동이륜차에 적용한 형태의 셀프밸런싱 기술 개발 결과를 소개한다. 우선, 제어모멘트자이로 및 전동이륜차의 동특성을 해석하여 roll 방향 균형을 유지하기 위한 상태 되먹임 제어기를 설계하였고 이로부터 제어모멘트자이로의 주요설계변수를 도출하였다. 또한 셀프밸런싱 성능 개발에 필요한 전동이륜차의 주요 파라메터를 추정하기 위한 알고리즘을 개발하여 시뮬레이션을 통해 성능을 검증하였다. 해석 결과를 바탕으로 제어모멘트자이로를 제작하여 실제 소형 전동이륜차에 탑재하였고 실험을 통해 셀프밸런싱 제어성능을 검증함으로서 개발된 기술의 타당성을 확인하였다.