Background: Child care center teachers are exposed to musculoskeletal injuries caused by repetitive movements at low heights due to the nature of their jobs. Self-myofascial release (SMFR) improves flexibility, pain, and functional performance. Pectoralis minor self-stretching (PMSS) improves muscle flexibility and postural alignment. PMSS has been commonly used to correct a rounded shoulder posture (RSP). Objectives: To examine the shoulder height, muscle tone, muscle stiffness, and muscle elasticity for women child care center teachers with RSP. Design: Randomized study. Methods: The participants were 20 women child care center teachers with RSP. They were randomly assigned two groups: SMFR group (n=10) and PMSS group (n=10). They performed each exercise for 20 min, 3 times a week for 4 weeks. They measured shoulder height, muscle tone, stiffness, and elasticity of upper trapezius before and after exercise. Results: In the shoulder height, there was no significant difference between two groups. There were significant decreases within both groups. In the muscle tone, stiffness, and elasticity, there was no significant difference between two groups and within two groups. Conclusion: SMFR using a hard massage ball and PMSS have a positive effect on posture correction for child care center teacher with RSP.

Background: Treadmill training is an effective intervention method for improving the walking ability of stroke patients, and taping is effective for stabilizing joints. However, taping interventions have not been implemented during treadmill training. Objectives: To examine whether treadmill training with an elastic tape or treadmill training with a non-elastic tape could be more effective in stroke patients. Design: A single blinded, randomized, controlled, comparative study. Methods: 22 stroke patients were randomly allocated to two groups: the elastic group (treadmill gait training with ankle elastic tape on the paretic side) or the non-elastic group (treadmill gait training with non-elastic tape on the paretic side). All participants performed 60 min of comprehensive rehabilitation therapy and treadmill training with an elastic tape or non-elastic tape for 20 min. Results: 10-meter walk test and timed up-and-go test results after training differed significantly from baseline in both groups (P<.05), but significantly larger gains were observed in the elastic group (10-meter walk test, -17.1%; timed up-and-go test, -18.49%; P<.05, respectively). Conclusion: Treadmill gait training with elastic tape on the affected ankle joint might be more effective at improving the walking and balancing abilities of stroke patients.

목적: 본 연구는 4가지 다른 프리즘 종류와 크기에 따른 측정 시 발생하는 오차를 수치화하고, 특히 낱개 프리즘을 사용할 때 발생하는 기울임에 의한 오차를 비교하고자 한다. 방법 : 각 4가지 유형의 프리즘 렌즈 수평 프리즘 바(H), 수직 프리즘 바(V), 낱개 프리즘(I), 프레넬 프리즘(F) 에 대해 4개씩 제품을 준비하여 실험을 진행했다. 1 m 거리에서 총 4번 같은 방향으로 측정했으며, H, V, I는 7가 지 프리즘(Δ), 프레넬 프리즘은 3가지 프리즘 크기를 측정하여 발생하는 오차를 비교하였다. 또한 낱개 프리즘의 경우 방향 오차로 인한 오차를 비교하기 위해 1, 3 및 5도를 측정하였고, 수평 방향으로 8가지 프리즘, 수직 방향 으로 6가지 프리즘 크기에 따른 오차를 비교했다. 결과 : 수평 방향에서 프리즘 렌즈를 측정한 결과, H와 I가 가장 오차가 적었으며 두 렌즈 간 차이는 크지 않았 다. F는 12 Δ에서 유의한 오차가 나타났으며(p<0.010), 20 Δ에서 V의 오차가 높아져 F와의 차이가 없었다. 수직 방향에서는 프리즘 크기가 작을수록 H와 V 사이에 차이가 없었으나, 16 및 20 Δ부터 H와 V에서 유의한 오차가 나타났다(p<0.010). I를 수평 및 수직 방향으로 3가지 각도로 기울였을 때, 2 Δ에서는 수평 및 수직 방향 모두에서 차이가 없었다. 그러나 4~20 Δ까지 프리즘 크기가 커질수록 수평 및 수직 방향 모두에서 기울기가 증가함에 따라 유의한 차이가 나타났다(p<0.010). 결론 : 본 연구의 결과에 따르면, 프레넬 프리즘에서 가장 많은 오차가 발생한 반면, 낱개 프리즘에서 가장 적은 오차가 나타났다. 프리즘 바는 수평 및 수직 방향으로 나누어져 있어 사용 목적에 맞게 정확히 사용해야 한다. 프 리즘 크기가 커질수록 측정 각도를 주의해야 하며, 임상에서는 오차가 적은 낱개 프리즘을 사용하는 것을 권장 한다.

Researchers have examined how individuals' preferred ways of comparing achievements differ according to their mindset. However, studies investigating the concomitant impact of such differences on individuals' happiness are relatively scant. Using a variety of scenarios, the present study examined how fixed-mindset and growth-mindset individuals' different achievement-comparison styles (more than others, less than others, better than before, and worse than before) affected their subjective happiness. A total of 880 participants were recruited. Fixed-mindset individuals felt happy when they felt they achieved more than others and unhappy when they felt the opposite, but were not influenced significantly when their achievement was better or worse than before. Conversely, growth-mindset individuals felt happy when their achievement was better than before but unhappy when it was the opposite, without being influenced significantly by achieving more or less than others. This study examined mindset, achievement comparison, and subjective happiness comprehensively, which, to date, have only been examined independently.

Drug-induced liver injury (DILI) is considered to be a significant cause of drug wastage. To mitigate clinical DILI risks, assessing drugs using human liver models is crucial since animal studies may fall short due to species-specific liver pathway variations. Cell-based preclinical hepatotoxicity testing is often pertinent. In the present study, cells from a human liver cancer line (HepG2 and HepaRG) were cultured in both formats of 2D and 3D spheroids to explore their responses to drugs. Liver-specific marker expressions across cell lines and culture formats were also examined to assess disparities in DILI marker expressions. After treating each cell with the drugs, cytotoxicity and liver injury markers aspartate aminotransferase and alanine aminotransferase were increased. In addition, liver specific markers albumin and urea decreased in a drug concentration-dependent manner. These findings were consistent with drug sensitivity. Additionally, mRNA expression levels of cytochrome P450 enzymes (CYPs) involved in hepatocellular drug metabolism were compared following treatment with enzyme inducers. CYP1A2 and CYP2C9 were not epxressed in HepG2 cells. HepaRG cells exhibited significantly increased expression of CYP1A2, 2C9, and 3A4 post-treatment. Notably, enzyme expression was notably higher in 3D cultures than in 2D cultures. Collectively, these findings suggest that HepaRG cells and 3D cultures hold promise for evaluating DILI during early-stage drug development.

This study evaluates the analytical performance of a newly developed miniaturized disposable U-tube for an automated blood viscometer and compares it to conventional viscometers. Whole blood viscosity (WBV), essential for circulatory function, exhibits non-Newtonian behavior, posing challenges for measurement at low shear rates. The blood viscometer, based on a scanning capillary tube method, used disposable U-tubes to measure viscosities across a shear rate range of 1s⁻¹ to 1,000s⁻¹. Precision evaluation showed stable coefficients of variation (CV) across different viscosity levels. Repeatability assessment indicated consistent CV values, demonstrating the reliability of the device. The agreement with the LV-III Brookfield viscometer and MCR 92 Rheometer was analyzed using Bland-Altman plots, which revealed minor systematic biases and consistent differences across the measurement range. Correlation analysis using Passing-Bablok regression showed high correlation coefficients (R > 0.96) with regression slopes close to 1. The newly developed miniaturized disposable U-tube exhibits excellent precision, reliable repeatability, and high correlation with established methods, enhancing laboratory productivity and offering potential for clinical applications. Further studies with human blood samples are recommended to confirm its clinical applicability.

Wall-embedded ventilators, which are commonly used for ventilation of buildings, greatly damage the aesthetics of the building due to pollutants such as dust and grease sticking to the fan and gaps of the ventilator as the period of use increases. For this aesthetic reason, it is often installed in a place that is not easily visible to people, and if the ventilation fan is not properly arranged and installed, it is difficult to maintain indoor air in an optimal state. In this study, the effect of the arrangement of ventilators on indoor ventilation performance was investigated. Comparisons were made between the case where three ventilators were concentrated and the case where they were spaced apart at regular intervals. It was found that the ventilation performance was different depending on the location where the ventilators were installed.

In the past, aviation technology developed from wood to alloys to composite materials. Propellers have also evolved from wood to composite materials for modern small aircraft. In this context, research is needed on a three-blade composite propeller based on the Rotax 912 engine, which is widely used in Korea. In this study, the goal is to select the optimal propeller pitch angle by investigating noise changes according to changes in blade angle and engine 4000RPM of three types of three-blade propellers different from each propeller manufacturer. By comparing the noise of the three types of propellers most commonly used in Korea and suggesting the minimum noise blade angle for each propeller, we aim to help aircraft operators select propellers and resolve noise complaints around airfields.

This study focused on improving the solubility of silodosin, a drug poorly soluble in water, by utilizing solid dispersions. Three types of dispersions were examined and compared against the drug powder: surface-attached (SA), solvent-wetted (SW), and solvent-evaporated (SE). Polyvinyl alcohol (PVA) was identified as the most effective polymer in enhancing solubility. These dispersions were prepared using spray-drying techniques with silodosin and PVA as the polymer, employing solvents such as water, ethanol, and a water-acetone mix. The physicochemical properties and solubility of the dispersions were evaluated. The surface-attached dispersions featured the polymer on a crystalline drug surface, the solvent-wetted dispersions had the amorphous drug on the polymer, and the solvent-evaporated dispersions produced nearly round particles with both components amorphous. Testing revealed that the order of improved solubility was: solvent-evaporated, solvent-wetted, and surface-attached. The results demonstrated that the preparation method of the solid dispersions significantly impacted their physicochemical properties and solubility enhancement.

There are two primary sludge drying methods such as the direct heating microwave method and the indirect heating steam one. In this study, the drying treatment facility at sewage treatment plant A applied both of these drying methods. The research aimed to investigate the optimal operation approach for the drying facility, considering the input sludge and the moisture content data after the drying process. Moisture content and removal rate data were executed at the research facility from January 2016 to December 2018. First, the microwave, a direct heating drying method, performed intensive drying only on the outer surface of the sludge by directly applying heat to the sludge using far infrared rays, so effective sludge drying was not achieved. On the other hand, the steam method of the indirect heating method used steam from a gas boiler to maximize the utilization of the heat transfer area and reduce energy of the dryer, resulting in an effective sludge drying efficiency. The sludge moisture content brought into the sludge drying facility was about 80%, but the moisture content of the sludge that went through the drying facility was less than 10% of the design standard. Therefore, the steam method of the indirect heating method is more effective than the microwave method of the previous direct heating method and is more effective for maintenance It has proven that it is an efficient method of operating construction facilities.

This study aims to compare six observational methods for assessing arm- and hand-intensive tasks, based on literature review. The comparison was conducted in viewpoints of body regions, force/external load, motion repetition, other factors including static posture, coupling, duration/break, pace, temperature, precision task, and final risk or exposure level. The number of risk factors assessed was more, and assessment procedure was more complex than the observational methods for assessing whole-body postural loads such as Ovako Working Posture Analysis System(OWAS), Rapid Upper Limb Assessment(RULA), and Rapid Entire Body Assessment(REBA). Due to these, the intra- and inter-reliabilities were not high. A past study showed that while Hand Arm Risk Assessment Method(HARM) identified the smallest proportion of the work tasks as high risk, Strain Index(SI) and Quick Exposure Check(QEC) hand/wrist were the most rigorous with classifying most work tasks as high risk. This study showed that depending on the observational technique compared, the evaluation factors, risk or exposure level, and evaluation results were different, making it necessary to select a technique appropriate for the characteristics of the work being assessed.

최근 우리나라에서 벌채와 산사태의 연관성에 대한 논란이나 숲가꾸기의 효과에 대한 의문이 제기되면서 산림관리에 대한 중요성이 더욱 강조되고 있다. 그러나 국내에서 이를 뒷받침하기 위한 정량적 평가자료는 부족한 실정이다. 이러한 배경을 바탕으로 이 연구는 수목 뿌리의 토양보강 효과에 대한 정량적 평가를 위한 연구주제와 방향성을 제언하고자 계량서지학적 분석을 이용하여 최근 30년(1990-2019)간의 국제·국내 관련 논문의 연구동 향을 비교·분석하였다. 그 결과, 국제 연구논문의 게재 편수는 증가 추세를 보였으며, 학문 분야와 연구영역이 다양화되어 있음이 확인되었다. 연구영역의 경우 수목 뿌리의 토양보강 메커니즘 규명(제1연구영역), 임분 조건에 따른 토양보강 효과 추정(제2연구영역), 수목 뿌리의 토양보강 효과를 고려한 사면안정성 평가(제3연구영역) 및 계안안정성 평가(제4연구영역)로 구분되었다. 이처럼 국외에서는 산사태 방지에 있어 산림생태계의 구조와 기능이 중요한 요소로 인식되었던 것으로 판단되었다. 반면, 국내 학술지는 제1연구영역과 제3연구영역만이 출현하여 상대적으로 기초적인 수준으로 확인되었다. 따라서 기후변화로 다변화되는 산림생태계의 산사태 방지 효과에 대한 정량적 평가를 위해서는 향후 다양한 수종뿐만 아니라 생육조건, 교란 이후 토양보강 효과의 변화를 규명하기 위한 제2연구영역과 관련된 연구가 활발히 수행되어야 할 필요가 있을 것으로 판단되었다.

본 논문은 중국 고대 우주론(宇宙論, cosmology)적 사유를 디지털인문학 (Digital Humanities)적 방법을 통해 비교, 분석하는 것을 목적으로 한다. 본 연 구는 철학과 사상을 대상으로 한 디지털인문학적 연구는 ‘대규모 데이터(big data)’를 이용한 연구보다는 오히려 특정 텍스트 안의 한정된 ‘소규모 데이터 (small data)’를 분류, 재구성, 시각화하고 분석함으로써 더 유의미한 결과를 얻 을 수 있다는 입장에서 시도되었다. 본 연구는 ｢태일생수｣에 대한 기존의 연구를 정리, 분석하여 디지털인문학 적 방법을 통해 기존의 연구를 보완할 지점을 도출하였다. 중국 최초의 우주론 적 텍스트 중 하나인 ｢태일생수(太一生水)｣와 중국 우주론에서 가장 중요한 위 치를 점하고 있는 ｢태극도설(太極圖說)｣을 중심으로 중국 고대 우주론의 텍스 트들을 디지털인문학적 방법을 통해 데이터화하고 구조화하여 비교함으로써 중국 고대 우주론의 연속성과 발전의 양상을 분석하였다. 본 연구는 ｢태일생수 ｣가 시간과 공간에서의 생성(generation)을 묘사하는 우주생성론(cosmogony)이지 만 우주의 공시적(共時的, synchronic) 구조를 관조하는 형이상학(metaphysics) 혹 은 존재론(ontology)의 단초 역시 가지고 있었고 후대 성리학의 ｢태극도설｣은 형이상학/존재론적 우주론이 극단적으로 강조된 모델임을 논한다.

촉각과 정서에 관해 이루어진 선행 연구들에서는 어떤 촉각 자극이 특정 정서를 유발하는가에 초점을 맞춰 진행되 었다. 또한, 시각이 촉각 지각의 과정에서 중요한 역할을 함에도 불구하고 촉각의 단일 양상에만 주목하여 연구가 진행되었다. 이에 본 연구에서는 촉각 자극을 활용하여 거칠기, 경도, 시각 차단 여부라는 세 가지 변인이 촉각 지각 에 따른 정서 경험에 미치는 영향을 알아보고자 하였다. 실험 자극은 일상생활에서 접할 수 있는 사물을 사용하였으 며, 거칠기 2조건(거친, 매끄러운), 경도 2조건(단단한, 부드러운)을 교차하여 ‘거친/단단한’, ‘거친/부드러운’, ‘매끄러 운/단단한’, ‘매끄러운/부드러운’이라는 4가지 조건에 맞게 선정하였다. 실험은 시각 차단 여부에 따라 두 세션으로 구분되었다. 참가자들은 촉각 자극을 보지 않으면서 만진 뒤에 평정하는 세션을 마치고, 촉각 자극을 보면서 만진 뒤에 평정하는 세션을 진행하였다. 반복측정 변량분석 결과, 보면서 자극을 만질 때 더 긍정적으로 느끼며, 보지 않으면서 자극을 만질 때 더 부정적으로 느낌을 확인하였다. 또한 매끄러운 자극과 부드러운 자극을 더 긍정적으로 느끼고 거친 자극을 더 부정적으로 느꼈으며, 이 경향이 보지 않고 만졌을 때 더 강했다. 본 연구의 결과는 시각 정보가 제공되는 경우와 제공되지 않는 경우 촉각 경험에 대한 정서 반응이 어떻게 다른지를 이해함으로써, 정서와 시각 정보 처리 간의 상호작용에 대한 이해를 높일 수 있다는 시사점을 가진다.

마비성 패류 독소(Paralytic shellfish poisoning, PSP)는 유해 조류에 의해 생성되며, 독소에 노 출된 수산물을 섭취하였을 때 중독이 발생한다. 수산물 중 PSP를 검출하는 표준 시험법인 Mouse bioassay (MBA)는 낮은 검출한계와 동물 윤리 문제로 대체 시험법의 개발 필요성이 대 두되고 있다. 이러한 대체 시험법 중, PSP가 신경 세포막의 Na+ 채널을 차단하는 기전을 이 용한 마우스 뇌신경 모세포종 세포 기반 시험법(Neuro-2a assay)의 표준화를 위한 노력이 대두 되고 있다. Neuro-2a assay의 원리는 Neuro-2a 세포주에 Na+/K+ ATPase 억제제인 Ouabain (O)과 Na+ 채널 활성화제인 Veratridine (V)을 처리하여 과도한 Na+ 유입으로 인한 세포사멸을 유도한 상태에서, Na+ 채널 억제제인 PSP를 처리하게 되면 Na+ 유입이 차단되어 세포가 생존 하는 것을 측정하는 것이다. 본 연구에서는 PSP 검출을 위한 Neuro-2a assay를 국내 연구 환 경에 맞게 다양한 매개변수를 개선하여 최적 시험법을 확립하고자 하였다. 고려한 매개변수 들은 세포밀도, 배양 조건 및 PSP 처리 조건 등으로, 그 결과는 아래와 같다. 초기 세포밀도 는 40,000 cells/well로, 세포 배양시간 및 처리시간은 각각 24시간으로 설정하였다. 또한 최적 O/V 농도는 500/50 μM로 설정하였다. 본 연구에서 PSP 중 Saxitoxin (STX)에 대해서 O/V 처 리가 된 상태에서 S자형 용량-반응 그래프가 도출되는 8가지 농도(368~47,056 fg/μl)를 확인 하였고, Neuro-2a assay의 실험실 간 변동성 비교를 통해, 실험의 적정성 확인을 위한 5가지 Quality Control Criteria와 실험 데이터의 신뢰가능 범위(Data Criteria) 6가지를 설정하였다. 확 립된 조건으로 Neuro-2a assay를 진행한 결과 반수영향농도(EC50) 값은 약 1,800~3,500 fg/μl 로 나타났다. 실험실 간 변동성 비교 결과, Quality Control Criteria 값 및 Data criteria 값의 변 동계수(coefficients of variation (CVs))가 1.98~29.15% 범위로 산출되어 실험의 적정성 및 재현 성이 확인되었다. 본 연구를 통해 우리나라에서 활용할 수 있는 PSP 검출용 Neuro-2a assay 시험법의 최적 조건 및 5가지 Quality control 기준을 제시하였고, PSP 중 대표적인 독소인 STX 을 대상으로 Neuro-2a assay를 실시한 결과 유의한 EC50 값을 산출할 수 있었으며, 향후 국 내 수산물을 대상으로 MBA를 대체할 수 있는 PSP 검출법으로 활용될 것으로 기대된다.

In response to the growing demand for high-performance lithium-ion batteries, this study investigates the crucial role of different carbon sources in enhancing the electrochemical performance of lithium iron phosphate ( LiFePO4) cathode materials. Lithium iron phosphate ( LiFePO4) suffers from drawbacks, such as low electronic conductivity and low lithium-ion diffusion coefficient, which hinder its industrial development. Carbon is a common surface coating material for LiFePO4, and the source, coating method, coating amount, and incorporation method of carbon have a significant impact on the performance of LiFePO4 materials. In this work, iron phosphate was used as the iron and phosphorus source, and lithium carbonate was used as the lithium source. Glucose, phenolic resin, ascorbic acid, and starch were employed as carbon sources. Ethanol was utilized as a dispersing agent, and ball milling was employed to obtain the LiFePO4 precursor. Carbon-coated LiFePO4 cathode materials were synthesized using the carbothermal reduction method, and the effects of different carbon sources on the structure and electrochemical performance of LiFePO4 materials were systematically investigated. The results showed that, compared to other carbon sources, LiFePO4 prepared with glucose as the carbon source not only had a higher discharge specific capacity but also better rate cycle performance. Within a voltage range of 2.5–4.2 V, the initial discharge specific capacities at 0.1, 0.5, and 1 C rates were 154.6, 145.6, and 137.6 mAh/g, respectively. After 20 cycles at a 1 C rate, the capacity retention rate was 98.7%, demonstrating excellent electrochemical performance.