국제해사기구는 국제해운의 온실가스 배출을 줄이기 위한 전략을 채택하였으며, 선박 기인 온실가스 배출을 줄이기 위해 보다 강화된 목표를 설정하고 있다. 액체수소를 기화시켜 연료로 사용하는 고분자 전해질 연료전지는 이러한 규제를 준수하기 위한 유망한 기 술 중 하나로 평가받고 있다. 일반적으로 선박시스템 설계는 선급의 규정에 따라야 하지만 환경규제가 강화됨에 따라 새로운 연료와 시 스템의 도입이 가속화되고 있으며, 이로 인해 규정개발이 기술의 도입을 따라가지 못하는 경우도 발생하고 있다. 이러한 격차를 해소하기 위해, 본 연구에서는 수소 연료가스공급 시스템을 대상으로 위험요소 및 운전분석 기법(HAZOP)과 보호계층분석 기법(LOPA)을 결합하여 신기술의 안전성을 검증하는 방법을 제시하였다. 먼저 HAZOP을 통해 위험 시나리오를 식별하고, LOPA를 통해 정성적인 HAZOP 결과를 정량적으로 보완하였다. 초기사건의 빈도와 독립보호계층(IPL)들의 작동 요구시 고장 확률(PFD)을 계산하였다. 기존 IPL의 적절성을 결정 하기 위해, 예상되는 완화 정도를 가정한 허용기준과 비교하였으며, 필요한 경우, 추가 IPL을 권장하였다. 본 연구를 통해서 HAZOP-LOPA 기법이 조선해양 분야에서 신기술의 안전성을 평가할 수 있는 잠재력을 가지고 있음을 확인하였다.

During the formation of large-scale structures in the universe, weak internal shocks are induced within the hot intracluster medium (ICM), while strong accretion shocks arise in the warm-hot intergalactic medium (WHIM) within filaments, and the warm-cold gas in voids surrounding galaxy clusters. These cosmological shocks are thought to accelerate cosmic ray (CR) protons and electrons via diffusive shock acceleration (DSA). Recent advances in particle-in-cell and hybrid simulations have provided deeper insights into the kinetic plasma processes that govern microinstabilities and particle acceleration in collisionless shocks in weakly magnetized astrophysical plasma. In this study, we adopt a thermal-leakage type injection model and DSA power-law distribution functions in the test-particle regime. The CR proton spectrum directly connects to the Maxwellian distribution of protons at the injection momentum pinj = Qppth,p. On the other hand, the CR electron spectrum extends down to pmin = Qepth,e and is linked to the Maxwellian distribution of electrons. Here, pth,p and pth,e, are the proton and electron thermal momenta, respectively. Moreover, we propose that the postshock gas temperature and the injection parameters, Qp and Qe are self-regulated to maintain the test-particle condition, as the thermal energy is gradually transferred to the CR energy. Under these constraints, we estimate the self-regulated values of the temperature reduction factor, RT , and the proton injection parameter, Qp, along with the resulting CR efficiencies, ηp and ηe. We then provide analytical fitting functions for these parameters as functions of the shock Mach number, Ms. These fitting formulas may serve as valuable tools for quantitatively assessing the impact of CR protons and electrons, as well as the resulting nonthermal emissions in galaxy clusters and cosmic filaments.

The purpose of this review is to provide a comprehensive analysis of the intricate relationships between cognitive control, depression, and emotion regulation. Cognitive control, encompassing processes such as attentional control, inhibitory control, and cognitive flexibility, plays a central role in regulating thoughts, behaviors, and emotions in alignment with internal goals and external demands. Depression, characterized by persistent feelings of sadness, hopelessness, and cognitive impairments, is associated with deficits in cognitive control processes. Emotion regulation strategies, such as cognitive reappraisal and expressive suppression, enable individuals to modulate emotional experiences and responses. The bidirectional relationships between cognitive control, depression, and emotion regulation underscore the complexity of cognitive and emotional processes in depression. Understanding these relationships is crucial for developing targeted interventions aimed at promoting cognitive and emotional well-being and preventing depression onset and recurrence. Moreover, recognizing the roles of cognitive control and emotion regulation in depression holds promise for informing clinical practice and enhancing therapeutic interventions. This review highlights the importance of considering cognitive control and emotion regulation in the assessment and treatment of depression and provides insights for future research and clinical practice.

대한민국의 해양레저산업은 세일링을 비롯한 다양한 형태의 수상레저 활동이 증가하는 추세에 따라 세계적으로 신흥시장으로 주목받고 있어 세일링 요트에 대한 수요가 높아질 것으로 추정된다. 이에 따라 2022년 현재 우리나라 요트 문화의 부흥과 보급을 위해 해 양수산부의 지원을 받아 28피트 세일 요트의 설계 및 개발이 착수되었다. 개발 초기 단계에서의 성능을 확인하고 이를 통해 설계 인자를 결정하기 위하여 속도 예측 프로그램 VPP(Velocity Prediction Program) 분석이 수행되었다. 본 연구에서 사용된 소프트웨어는 University of Southampton의 Wolfson Unit社의 WinDesign으로, 속도 예측에 적용된 유체역학적 데이터 모델은 Wolfson Unit社자체적인 조선공학 및 요트 연구 분야에서 수십 년간의 예인 수조 시험 데이터를 회귀 분석한 방법으로 대부분의 현대식 요트에 대해 신뢰할 수 있는 추정치를 제공 하는 것으로 여겨진다. 하지만 예인 수조 시험이나 CFD 수치해석 등을 통한 실험 결과적인 유체역학적 정보가 없기 때문에 소프트웨어에 서 제공하는 유체역학적 데이터 회귀 모델의 저항 값은 다소 차이가 있을 것으로 예상된다. 또한, 아직 미완료된 무게 중심 추정에 의한 VCG 값은 속도 예측의 입력 변수 중 하나로, 성능 결과에 어느 정도 영향을 미칠 수 있을 것으로 예상된다. 개발 세일 요트에 대한 최적 화된 보트 속도는 풍속 4, 8, 12, 16 및 20노트의 집세일 조합(최대 120° TWA) 및 스피네커 세일 조합(80° TWA부터) 모두에서 확인되었으 며, VPP를 활용하여 얻어진 최적화된 속도는 국제적으로 유사한 등급의 요트와 견줄수 있는 수준으로 확인되었다.

Background: Platelet-derived growth factor receptor alpha (PDGFRα) is essential for various biological processes, including fetal Leydig cell differentiation. The PDGFRαEGFP mouse model, which expresses an eGFP fusion gene under the native Pdgfrα promoter, serves as a valuable resource for exploring PDGFRα’s expression and function in vivo. This study investigates PDGFRα expression in adult testicular cells using PDGFRαEGFP mouse model. Methods: Genotyping PCR and gel electrophoresis were used to confirm the zygosity of PDGFRαEGFP mice. Histological examination and fluorescence imaging were used to identify PDGFRα expression within testicular tissue. Immunohistochemical analysis assessed the co-expression of PDGFRα with c-Kit, ANO-1, and TASK-1 in testicular cells. Results: Genotyping confirmed the heterozygous status of the mice, which is crucial for studies due to the embryonic lethal phenotype observed in homozygotes. Histological and fluorescence imaging revealed that PDGFRα+ cells were primarily located in the interstitial spaces of the testis, specifically within Leydig cells and peritubular myoid cells (PMCs). Immunohistochemical results showed PDGFRα co-localization with c-Kit and ANO-1 in Leydig cells and a complete co-localization with TASK-1 in both Leydig cells and PMCs. Conclusions: The findings demonstrate specific expression of PDGFRα in Leydig cells and PMCs in adult testicular tissue. The co-expression of PDGFRα with c-Kit, ANO-1, and TASK-1 suggests complex regulatory mechanisms, possibly influencing testicular function and broader physiological processes.

본 연구는 소리곤충을 활용한 동물매개치료 프로그램이 노인의 우울에 어떠한 영향을 미치는지 살펴보고자 하였다. 연구대상은 I시에 위치한 I치매안심센터에서 추천을 받은 우울 척도 검사에서 5점 이상을 받은 노인 20명이며, 실험집단과 통제집단 각 10명을 선정하였다. 프로그램은 2023년 6월부터 8월까지 주 1회, 회기당 50분 씩 총 12회기를 실시하였다. 효과 검증을 위해 SPSS v.26을 활용하여 집단 간 동질성 검증(Mann-Whitney U test)을 하여 동질성이 입증이 된 후 각 집단의 사전과 사후에 노인 우울 척도 측정을 실시하고 비모수 윌콕슨 부호 순위 검정(Wilcoxon signed-rank test)으로 분석하였다. 그 결과, 실험집단의 우울 전체의 사전・사후에 유의미한 차이 가 나타났다(Z=-3.53, p＜.05). 그러나 통제집단의 우울 전체의 사전・사후에는 유의미한 차이가 나타나지 않았 다(Z=-1.06, p>.05). 따라서 본 연구는 소리곤충을 활용한 동물매개치료 프로그램이 노인의 우울에 긍정적인 영향 을 준 것으로 확인이 되었다. 이번 연구결과는 소리곤충을 활용한 정서 및 심리 치료에 대한 과학적 근거를 제시하 여 관련 분야 활성화에 기여할 수 있을 것으로 기대된다.

Hindwings of many lycaenid butterflies have a unique tail-like wing structure referred to as a false head, which actually mimics the antennae. False heads increase butterfly survival by directing predatory attacks towards the false heads thereby enhancing the chance of escape. In this study, using discrete character evolution models of European and American butterflies, we examined the co-evolutionary patterns between false head structures and two associated traits: a highly contrasting color patch neighboring the false head, and hindwing rubbing behaviors. The former is considered a eye-mimicking structure that enhances the effectiveness of false head, and latter generates the movement of false heads which likely increases the success of false head deception. Our findings demonstrate that false heads are ancestral states for both European and American lycaenids. Both contrasting colors and hindwing rubbing behaviors follow correlated evolution models, suggesting that these traits co-evolved in lycanid butterflies. However, specific evolutionray patterns differed between the two continents.

깡충거미과의 모습을 의태하여 시각적 포식자인 깡충거미로부터 자신을 보호하는 전략은 여러 나비목 곤충 에서 진화하였다. 하지만 나비목 곤충이 깡충거미 간의 의사소통 신호를 의태한다는 가설은 제안된 바 없다. 본 연구에서는 깡충거미과의 구애/영역성 행동을 의태하는 것으로 추정되는 붉은꼬마꼭지나방(Atkinsonia ignipicta)의 빗살 모양 더듬이와 추켜 올린 다리가 포식을 단념시키는 의태 신호로 작동하는지 실험적으로 검증 하였다. 깡충거미 의태라 추측되는 붉은꼬마꼭지나방의 형태적 및 행동적 특성들을 단계적으로 제외한 뒤 포식 자(흰눈썹깡충거미, Evarcha albaria)와의 조우 시 생존을 비교하였다. 연구 결과, 붉은꼬마꼭지나방은 비슷한 크기의 비-의태 나방에 비해 포식자의 공격을 덜 받았으며, 더듬이나 다리 중 하나라도 결여되었을 때 흰눈썹깡충 거미의 공격이 증가하였다. 이는 붉은꼬마꼭지나방의 더듬이와 다리 모두가 시각적 방어의 중요한 신호로 작동 한다는 것을 시사한다. 하지만 흰눈썹깡충거미가 붉은꼬마꼭지나방을 향해 구애/영역성 행동을 보이지 않았다 는 점에서 깡충거미의 낮은 공격 빈도가 같은 깡충거미 종류로 오인해서인지 다른 이유에서인지는 불투명하다. 그러나 사층깡충거미(Marpissa pulla)는 붉은꼬마꼭지나방을 상대로 영역성 행동을 잦은 빈도로 보였으며, 이는 붉은꼬마꼭지나방의 형태가 깡충거미 의태 효과를 가진다는 것을 보여준다.

Distractive marking, as conceptualized by Abbott H. Thayer, refers to diminutive patterns of contrasting colors on an animal’s body. Thayer hypothesized that these patterns augment camouflage by diverting predatory focus from the outline of the prey, however, the evidence was insufficient. In this study, we verified the hypothesis that the presence of distractive markings confers a survival advantage under specific conditions. Specifically, the experiment aimed to ascertain whether the existence of lichens on trees hinders the visual detection of prey, given that lichens resemble distractive markings. The experimental design involved human subjects as predators and artificial moth images on a monitor as prey. The survival of moths with and without distractive markings was compared, also considering the influence of the presence of lichens in the background. As an analysis result, the survival likelihood of moths was statistically significantly hindered when the distractive marking was present. This result contradicts Thayer‘s hypothesis and implies the presence of a function distinct other than the enhancement of camouflage.

In this study, we evaluated wound healing following the use of 3% topical povidone ointment in dogs with minor wounds and evaluated it as a new wound treatment applicable to veterinary medicine. Twenty-six dogs that had suffered minor wounds such as abrasions, punctures, and incised wound within 8 hours were recruited, and all treatments were performed with the consent of their owners. Vitality, behavioral symptoms, and dermal symptoms due to wounds were evaluated between the povidone ointment group (n=18) and the control group (chlorhexidine group, n=8). As a result of evaluating changes in vitality and behavior, the povidone ointment group showed improvement to 1.94 (±2.53), 0.61 (±1.34), and 0.39 (±1.24) while the chlorhexidine group showed improvement to 2.00 (±1.6), 0.87 (±0.99), and 0.86 (±0.99) on days 0, 3, and 7 respectively, showing similar improvement in symptoms between the two groups (p>0.05). When observing wound symptoms, most of the swelling and inflammation improved within 3 days. The averages for the chlorhexidine group on days 0, 3, and 7 were 4.88 (±2.85), 2.88 (±2.64), and 2.38 (±2.39), and for the povidone ointment group, 5.55 (±3.22), 3.83 (±3.07), and 1.38 (±1.61), respectively. The wound healing effect of the povidone ointment group was similar to that of the chlorhexidine group (p>0.05). Through this study, we believe that topical povidone ointment can be applied to various wounds by replacing chlorhexidine.

This study develops and validates an English communicative competence model for Korean high school students, in response to the need to redefine the relevant concepts and components of competence that are demanded by the rapidly evolving future society. Drawing on Celce-Murcia’s (2008) theoretical model on communicative competence, this research conceptualized a model that could assess high school students’ English communicative competence by examining relevant domestic and international studies as well as theoretical reflections. Expert opinions from a two-stage Delphi survey were compiled and incorporated to revise, supplement, and validate the English communicative competence among high school students reflecting Korea’s English education environment. Following this process, the conceptual model for English communicative competence was reorganized into five sub-competences (sociolinguistic, discourse, linguistic, interactional, and strategic competence) and 15 corresponding subfactors. The content validity ratio values for the conceptual definition and factor structure of this model were all above 0.64, thus affirming the validity of the conceptual definition and factor structure.

This study investigates the impact of magnetic turbulence on cosmic ray (CR) electrons through Fermi-II acceleration behind merger-driven shocks in the intracluster medium and examines how the ensuing synchrotron radio emission is influenced by the decay of magnetic energy through dissipation in the postshock region. We adopt simplified models for the momentum diffusion coefficient, specifically considering transit-time-damping resonance with fast-mode waves and gyroresonance with Alfvén waves. Utilizing analytic solutions derived from diffusive shock acceleration theory, at the shock location, we introduce a CR spectrum that is either shock-injected or shock-reaccelerated. We then track its temporal evolution along the Lagrangian fluid element in the time domain. The resulting CR spectra are mapped onto a spherical shell configuration to estimate the surface brightness profile of the model radio relics. Turbulent acceleration proves to be a significant factor in delaying the aging of postshock CR electrons, while decaying magnetic fields have marginal impacts due to the dominance of inverse Compton cooling over synchrotron cooling. However, the decay of magnetic fields substantially reduces synchrotron radiation. Consequently, the spatial distribution of the postshock magnetic fields affects the volume-integrated radio spectrum and its spectral index. We demonstrate that the Mach numbers estimated from the integrated spectral index tend to be higher than the actual shock Mach numbers, highlighting the necessity for accurate modeling of postshock magnetic turbulence in interpreting observations of radio relics.

Background: Leydig cells, crucial for testosterone production, express ion channels like ANO1 that influence hormone secretion. This study investigates the expression and role of the Tandem of P domains in a weak inward rectifying K+ channel-related Acid-Sensitive K+-1 (TASK-1) channel in these cells, exploring its impact on testicular function and steroidogenesis. Methods: TASK-1 expression in Leydig cells was confirmed using immunostaining, while RT-PCR and Western Blot (WB) validated its expression in the TM3 Leydig cell line. The effect of a TASK-1 channel blocker on cell viability was assessed through live/dead staining and MTT assays. Additionally, the blocker’s effect on testosterone secretion was evaluated by measuring testosterone levels. Results: Immunohistochemical analysis revealed a predominant presence of TASK- 1, along with c-Kit and ANO-1, in Leydig cells adjacent to seminiferous tubules and also in Sertoli and spermatogenic cells. Expression levels of TASK-1 mRNA and protein were significantly higher in TM3 Leydig cells compared to TM4 Sertoli cells. In addition, blocking TASK-1 in TM3 cells with ML365 induced cell death but did not affect LHinduced testosterone secretion. Conclusions: These findings suggest that TASK-1 in Leydig cells is crucial for their viability and proliferation, highlighting its potential importance in testicular physiology.

This study investigated whether the framework of writing for English learners should be guided by the well-established reading-writing relation or by the receptive and productive nature of literacy skills. The writings of 209 advanced English learners in Korea were analyzed in relation to receptive and productive vocabulary knowledge and reading comprehension while controlling for writing fluency. Two sets of structural equation models were fitted: (1) productive skills (productive vocabulary and writing fluency) mediating receptive skills (receptive vocabulary and reading) and (2) reading mediating receptive and productive vocabulary knowledge. The results supported the second model in which reading completely mediated the contribution of receptive and productive vocabulary to writing. Although there were no direct effects of receptive and productive vocabulary knowledge, both had significant indirect effects on writing through reading and writing fluency. These results show that reading has a strong direct effect on writing above and beyond vocabulary, and that vocabulary knowledge contributes to writing development through reading.