Background: Chronic low back pain (CLBP) is a common health problem among female caregivers. In Korea, 70.4% of caregivers experience LBP after caregiving. The prevalence of LBP was higher in female caregivers of patients who required physical assistance with transfer than in those caring for patients who did not require physical assistance. Lifting movements, such as patient transfer and positioning, are associated with lumbopelvic stability (LPS) and knee muscle strength. However, no studies have investigated the differences in LPS and knee muscle strength between female caregivers with and without CLBP. Objects: This study was conducted to investigate the differences of the LPS, knee extension strength (KES) and knee flexion strength (KFS) between female caregivers with and without CLBP. Methods: Thirty-one female caregivers participated in this study. Participants were divided into two groups: (1) caregivers without CLBP (n = 13) and (2) caregivers with CLBP (n = 18). LPS, KES, and KFS levels were measured. An independent t-test was used to compare the LPS, KES, and KFS between caregivers with and without CLBP. The statistical significance was set at α of 0.05. Results: The LPS and KES scores were significantly lower in caregivers with CLBP than those without. In contrast, the KFS did not differ significantly between the groups. Conclusion: This study observed associations of both LPS and KES with CLBP among female caregivers.

Mauremys reevesii (Reeves’ turtle) is an endemic freshwater turtle species found throughout East Asia. Due to a rapid population decline, the International Union for Conservation of Nature (IUCN) and the Korean government have classified this species as Endangered (EN). The reported largest population size of M. reevesii in the Republic of Korea was previously estimated to be approximately 20-30 individuals. Our study assessed the population size and structure of M. reevesii at Geumho Reservoir, Republic of Korea, using a capture-recapture data. A total of 433 M. reevesii were incidentally captured during a 35-week trapping process conducted from March to October 2023. The sex ratio of the captured population exhibited a male bias of 1.3 : 1. Sexual size dimorphism was observed only in body weight. Individuals were recaptured up to 11 times during the study period, with males and females being recaptured at an average of 2.1±2.0 times and 1.5±0.9 times, respectively. The estimated population size of M. reevesii in Geumho Reservoir was approximately 891 turtles. The absence of notable sexual size dimorphism and significant sex ratio differences suggests that the population in this area may have been established relatively recently. Compared to previous records, the population in Geumho Reservoir represents the largest single population of M. reevesii, both within the Republic of Korea and globally.

이 연구는 다목적 선박(MPV)의 공기역학적 구조물 설계, 분석 및 향상을 통해 그린 워터 압력에 의한 구조적 안전을 보장하고, 탈탄소화 및 에너지 효율성에 이바지하는 방법을 기술하였다. 유한 요소 분석(FEA)을 통한 초기 평가에서 좌굴 발생에 대한 잠재적인 취약점 이 있음을 확인하였다. 이러한 문제를 해결하기 위해 보강재(Carling stiffener)와 두께 증가를 통하여 응력을 재분배하고 국부적인 좌굴 발생의 위험을 최소화하였다. 보강 후 분석 결과, 한국선급(KR)의 안전 기준인 항복 강도, 미국 선급(ABS) 좌굴 강도 및 노르웨이 표준(NORSOK) 변 위 기준을 모두 충족하는 것이 확인되었다. 결과적으로 고유치 좌굴 해석 결과가 안전 기준을 초과하고 최대 변위가 허용 한계 내에 있는 등 중요한 개선이 이루어졌다. 이러한 개선은 극한의 해양 조건에서 운영 신뢰성을 보장할 수 있다. 이 연구는 공기역학적 항력 감소와 구조적 안전성의 이중적인 이점을 강조하며, 국제 해사 기구(IMO)의 2050 탈탄소화 목표에 부합하는 연료 효율성 및 온실가스 배출 감소에 이바지할 수 있다. 연구 결과는 다양한 선박 유형에 걸쳐 항력 감소 기술을 확장하기 위한 기초 자료를 제공하며, 지속 가능하고 탄력적인 해양 운영을 위한 대안을 제시하였다. 향후 연구는 구조적 안전 평가를 가속할 수 있는 단순화된 모델링 기술 개발에 집중할 것이다.

목적 : 본 연구는 중국 안과병원에 방문한 저도와 중등도 근시 청소년을 연구 대상으로 각막굴절교정 렌즈에 의한 단기간의 근시 진행 억제 효과가 있는지 관찰하고자 하였다. 방법 : J안과에 방문한 근시환자 중 40명의 환자 저도 근시군 20명(40안), 중등도 근시군 20명(40안)을 대상으 로 각막굴절교정 렌즈를 처방하고 6개월 동안 추적 관찰하였다. 각막굴절교정 렌즈 착용 후 1개월, 3개월, 6개월 후 각각 각막굴절교정 렌즈 교정 후 시력과 안축의 길이, 각막곡률, 안압, 각막 중앙 두께 등을 검사하여 분석 및 비교하였다. 통계분석은 SPSS 27.0 소프트웨어를 사용하였다. 결과 : 저도근시군과 중등도근시군의 교정시력이 모두 향상되었으며, 두 군 간의 차이는 통계학적 으로 유의하 였으며, 안축 길이는 중등도근시군의 안축 성장이 작았고, 두 군 간의 차이는 통계학적으로 유의하였다. 각막 곡률 은 중등도 근시 군의 각막 곡률이 더 많이 감소했으며, 두 군 간의 차이는 통계적으로 유의했다. 각막굴절교정 렌 즈를 착용한 환자는 안압과 각막 중앙 두께 측면에서 기준치와 유의한 변화가 없었다. 결론 : 각막굴절교정 렌즈는 청소년의 근시를 효과적으로 교정되었으며, 근시 진행을 억제하는 방법 중 하나로 근시 정도에 따라 차이가 있었다. 또한 청소년들의 근시 통제 효과는 중등도 근시 환자가 저도 근시 환자보다 더 효과적이었다.

Following the previous study, which investigated the pharmacological properties of the Technekitty injection (Tc-99m), the toxicity of a single intravenous administration of the Technekitty injection (Tc-99m) and the side effects that may occur at the diagnostic dose were confirmed. The Technekitty injection (Tc-99m) was administered intravenously once at a dose of 0, 0.67, 2.0, and 6.0 mCi/kg to 5 male and female rats per group. Mortality, general symptom observation, and weight measurement were performed for 2 weeks, followed by observation of autopsy findings. There were no deaths, and no statistically significant weight change was observed. No abnormal systemic signs related to the Technekitty injection (Tc-99m) were observed. These results confirmed that Technekitty injection (Tc-99m) can be safely administered intravenously at doses up to 6.0 mCi/kg. Additionally, technetium-99m at an average dose of 2 mCi (74 MBq) has been verified as a diagnostic dose without adverse effects, allowing the Technekitty injection (Tc-99m) to be used safely without side effects at this dosage. This study demonstrates that the Technekitty injection (Tc-99m) has a wide safety margin, supporting its potential for clinical application. Moreover, these findings align with the nonclinical safety standards for radiopharmaceuticals, reinforcing its utility in veterinary medicine. The Technekitty injection (Tc-99m) is expected to be applicable for clinical diagnosis as a veterinary drug in Korea.

Background: The widespread use of smartphones and personal computers has contributed to a rise in thoracic kyphosis, a condition characterized by excessive outward curvature of the upper back. This condition can lead to reduced lung function, poor posture, and decreased spinal angles, all of which can cause reductions in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). Furthermore, these issues are often associated with scapular protraction and anterior tilting. Objects: This study aimed to investigate the effects of using a scapular support pillow in people with thoracic kyphosis, as well as determine the changes in respiratory capacity and postural alignment. Methods: Forty-one participants (25 males and 16 females) with thoracic kyphosis (Cobb angle > 40°) were included in the study. Their respiratory function (FVC, FEV1) and body posture (spinal angle, chest expansion, acromion-to-the-wall index) were measured before and after using the scapular support pillow for approximately 30 minutes. FVC, FEV1, spinal angle, chest expansion, and acromion-to-the-wall index were analyzed using paired-t test. The level of statistical significance was set at p < 0.05. Results: The results demonstrated significant improvements in all measured parameters. Both respiratory function and posture-related metrics showed notable increases after using the scapular support pillow. Conclusion: The use of a scapular support pillow can effectively improve respiratory function and postural alignment in patients with thoracic kyphosis. Our research makes a meaningful contribution by proposing an effortless and convenient treatment option for individuals with thoracic kyphosis.

본 연구는 이주배경 청소년의 문화적응 스트레스가 사회적 역량에 영향을 미치는지를 분석하고, 문화적 응 스트레스가 사회적 역량에 미치는 영향에서 문화여가활동의 조절효과를 검증하는 것을 목적으로 하였다. 이를 위해 분석 자료는 한국청소년정책연구원의 ‘다문화청소년패널(MAPS: Multi-cultural Adolescent Panel Study)’ 2기 제1차(2019년) 조사 데이터를 사용하였으며, 연구대상은 이주배경 청소년 총 1,834명 이다. 이에 따른 주요 연구결과는 다음과 같다. 첫째, 문화적응 스트레스는 이주배경 청소년의 사회적 역량 에 부적인 영향을 미치는 것으로 확인되었다. 둘째, 문화여가활동은 이주배경 청소년의 문화적응 스트레스 와 사회적 역량의 관계에서 조절효과를 가지는 것으로 나타났다. 즉, 문화여가활동은 문화적 스트레스가 사회적 역량에 주는 부정적 영향을 완충시켜주는 것으로 나타났다. 이상의 연구결과를 토대로 이주배경 청 소년의 문화적 스트레스 감소시키고 사회적 역량을 향상시키는 문화여가활동을 활성화하는 정책적, 실천적 방안을 제안하였다.

Silicon carbide (β-SiC) was synthesized through an improved sol–gel method, then Ni/SiC catalysts were prepared using a hydrothermal method. The catalysts were characterized using TEM, H2- TPR, CO2- TPD and N2- TPD, etc. The results showed that the synthesized β-SiC had a large specific surface area, promoting the dispersion of Ni species and thus exposing more active sites. The interaction between Ni species and β-SiC contributed significantly to catalytic performance. Furthermore, the strong alkalinity of catalyst could adjust the bond energy of the active metal and N (M–N), which were conducive to desorption of the recombinant N2 from the metal surface, promoting to ammonia decomposition. Among the Ni/SiC catalysts, 30Ni/SiC-700 synthesized with the Ni loading of 30 wt% and calcination temperature of 700 °C, exhibited the optimal ammonia conversion rate of 93.4% at 600 °C under the space speed of 30,000 mL∙gcat −1∙h−1, and demonstrated a long-term stability, suggesting a very promising catalyst in ammonia decomposition.

This study involved the heterogenization of a binder pitch (BP) using a small amount of nanocarbon to improve physical properties of the resulting graphite electrode (GE). Heterogenization was carried out by adding 0.5–2.0 wt.% platelet carbon nanofiber (PCNF) or carbon black (CB) to a commercial BP. To evaluate the physical properties of the BPs, we designed a new model graphite electrode (MGE) using needle coke as a filler. The heterogenized binder pitch (HBP) with PCNF or CB clearly increased the coking value by 5–13 wt.% compared to that of the as-received BP. Especially, the model graphite electrodes prepared with HBPs containing 1.0 wt.% PCNF or CB showed significantly improved physical properties compared to the control MGE from the as-received BP. Although the model graphite electrodes prepared with HBPs showed similar properties, they had smaller pore sizes than the control. This indicates that heterogenization of the BP can effectively decrease the pore size in the MGE matrix. Correlating the average pore sizes with the physical properties of the model graphite electrodes showed that, for the same porosity, matrices formed by the HBP with a smaller average pore size can effectively improve the apparent density, tensile strength, and oxidation resistance of the model graphite electrodes.

Activated carbon has broad application prospects for treating pollutants due to its easy availability, low cost and good adsorption. In our work, nano-activated carbons (NAC) with abundant functional groups are obtained by the oxidation modification of HNO3, ( NH4)2S2O8, and KMnO4, which are used to construct the particle electrodes to degrade NDEA in a continuous flow electrochemical reactor, and the influence of relevant factors on the performance of NDEA removal is discussed. The experimental data show that the optimal degradation efficiency is 42.55% at the conditions of 3 mL/min influent water flow, 0.21 M electrolyte concentration, 10 mA/cm2 current density, and 10 μg/mL initial NDEA concentration. The degradation of NDEA conforms to a quasi second order kinetic equation. The electrocatalytic mechanism of NAC electrodes for removing NDEA is firstly discussed. The effects of different free radicals on the degradation of NDEA are also demonstrated through free radical quenching experiments, indicating that the degradation of NDEA is dominated by ⋅OH. The degradation pathway of NDEA and final products are obtained using GC–MS. NAC particle electrodes as the cheap and efficient electrocatalyst in continuous flow electrochemical reactor system provide a greener solution for the removal of disinfection by-products from drinking water.

Among the products of the electrocatalytic reduction of carbon dioxide (CO2RR), CO is currently the most valuable product for industrial applications. However, poor stability is a significant obstacle to CO2RR. Therefore, we synthesized a series of bimetallic organic framework materials containing different ratios of tungsten to copper using a hydrothermal method and used them as precursors. The precursors were then subjected to pyrolysis at 800 °C under argon gas, and the M-N bimetallic sites were formed after 2 h. Loose porous structures favorable for electrocatalytic reactions were finally obtained. The material could operate at lower reduction potentials than existing catalysts and obtained higher Faraday efficiencies than comparable catalysts. Of these, the current density of WCu-C/N (W:Cu = 3:1) could be stabilized at 7.9 mA ‧ cm-2 and the FE of CO reached 94 % at a hydrogen electrode potential of -0.6 V (V vs. RHE). The novel materials made with a two-step process helped to improve the stability and selectivity of the electrocatalytic reduction of CO2 to CO, which will help to promote the commercial application of this technology.

사범대학 학생은 대학생일 뿐만 아니라 미래의 교사로서 자신의 핵심 소양을 향상시킬 뿐만 아니라 학생의 핵심 소양을 발전시키는 중요한 책 임을 져야 한다. 본 논문의 연구 목적은 사범생의 직업적 인식이 핵심 소양에 미치는 영향을 조사하는 것이다. 연구 방법은 정량적 연구 방법 과 SPSS 26.0 통계 소프트웨어를 사용하여 데이터를 분석하였다. 연구 결과는 사범생의 직업 정체성과 핵심 소양 사이에 유의미한 정적 상관관 계가 있음을 보여주며, 직업적 정체성의 각 차원은 핵심 소양에 예측 효 과가 있는 것을 보여 주었다. 이 연구를 통해 우리는 사범생의 핵심 소 양 형성에 영향을 미치는 요인과 메커니즘을 찾고 사범생의 인재 양성과 기초 교육 발전을 향상시키기 위한 이론적 참고 자료를 제공한다.

Moso bamboo, as a kind of renewable functional material, exhibits outstanding development potential. It is promising to prepare activated carbon with good mechanical strength and high specific surface area using moso bamboo as raw material. In this work, we employed a hydraulic extruder to extrude the bamboo charcoal and the adhesive to obtain the moso bamboo activated carbon, and improved the specific surface area of the columnar activated carbon through high-temperature water vapor activation. Through the catalytic role of the water vapor activation process, the formation and expansion of the pores were promoted and the internal pores were greatly increased. The obtained columnar activated carbon shows excellent mechanical strength (93%) and high specific surface area (791.54 m2/ g). Polyacrylamide@asphalt is one of the most effective adhesives in the high-temperature water vapor activation. The average pore size (22.99 nm) and pore volume (0.36 cm3/ g) of the prepared columnar activated carbon showed a high mesoporous ratio (83%). Based on the excellent pore structure brought by the activation process, the adsorption capacity of iodine (1135.75 mg/g), methylene blue (230 mg/g) and carbon tetrachloride (64.03 mg/g) were greatly improved. The resultant moso bamboo columnar activated carbon with high specific surface area, excellent mechanical properties, and outstanding adsorption capacity possesses a wide range of industrial applications and environmental protection potential.

We successfully synthesized a porous carbon material with abundant hexagonal boron nitride (h-BN) dispersed on a carbon matrix (p-BN-C) as efficient electrocatalysts for two-electron oxygen reduction reaction ( 2e− ORR) to produce hydrogen peroxide ( H2O2). This catalyst was fabricated via ball-milling-assisted h-BN exfoliation and subsequent growth of carbon structure. In alkaline solutions, the h-BN/carbon heterostructure exhibited superior electrocatalytic activity for H2O2 generation measured by a rotating ring-disk electrode (RRDE), with a remarkable selectivity of up to 90–97% in the potential range of 0.3–0.6 V vs reversible hydrogen electrode (RHE), superior to most of the reported carbon-based electrocatalysts. Density functional theory (DFT) simulations indicated that the B atoms at the h-BN heterostructure interface were crucial active sites. These results underscore the remarkable catalytic activity of heterostructure and provide a novel approach for tailoring carbon-based catalysts, enhancing the selectivity and activity in the production of H2O2 through heterostructure engineering.