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A comparison of the meridional meandering of extratropical precipitation during boreal winter: eddy momentum flux versus Eulerian storm tracks
No full textThe latitudinal distribution of winter extratropical precipitation is often regarded as being determined by the location and intensity of the storm track. Here, we compare the precipitation variability associated with the meridional eddy momentum flux (EMF) with that associated with an Eulerian storm track measure. Observations show that when the midlatitude EMF is anomalously poleward, the occurrence of moderate-to-heavy precipitation (1-33 mm day-1) increases between 45 degrees N and 70 degrees N, while decreasing between 25 degrees N and 45 degrees N. This shift occurs mostly downstream of the climatological storm track maximum, with generally greater precipitation anomalies compared to those associated with storm track changes. The shift is tied to changes in horizontal moisture transport primarily by planetary scale waves. These results suggest that, in addition to the storm track intensity, dynamics of the horizontal wave tilts which affect the EMF intensity need to be considered when projecting future changes in precipitation variability.Y
Elucidating lithium-ion diffusion kinetics in cation-disordered rocksalt cathodes
No full textDisordered rocksalt (DRX) cathodes have emerged as a promising alternative to conventional nickel/cobalt-based layered oxides owing to their higher specific capacities using earth-abundant elements. However, the poor rate capability of DRX is a critical bottleneck in practical battery operations, which is often attributed to sluggish lithium and/or electronic conduction. In this study, we elucidated the lithium diffusion mechanism in DRX, exploiting a 'diffusion cluster' model within a machine-learning scheme, thus effectively addressing the complexity of randomly distributed cations in the structure. Our findings revealed that DRXs intrinsically possess various diffusion paths with activation barriers that widely range from 200 meV to 1.3 eV owing to diverse lithium hopping environments created by disordered cations. Notably, we discovered that migration bottlenecks along lithium percolation paths are primarily caused by large energy differences between lithium sites (as high as similar to 1 eV) rather than the transition state energy during lithium hopping, contrary to the conventional diffusion mechanism in ordered structures. The significantly broad distribution of lithium site energies is attributed to the distortion of the shape and size of lithium sites in oxides caused by disordered cations in DRX, e.g., Li1.2Mn0.4Ti0.4O2. Consequently, the large energy step from one site to the other acts as a de facto barrier for lithium hopping, impeding the overall lithium diffusion process. This new finding suggests that the key to improve the rate performance of DRX lies in flattening the landscape of lithium site energies, thus balancing the degree of cation disorder in DRX.N
Ultra-processed food intake, genetic polymorphisms and the risk of dyslipidaemia in the adult Korean population
No full textObjective: This study aimed to examine the association between ultra-processed food intake and dyslipidaemia risk and whether this association varied by the polygenic score for dyslipidaemia in the adult Korean population. Design: Prospective cohort study. Setting: Ultra-processed foods were identified under the NOVA classification. Participants were categorised into < 5, 5 to < 10, 10 to < 15, 15 to < 20 and >= 20 %E/d of ultra-processed food intake. The polygenic scores for dyslipidaemia were calculated from 53 950 SNPs. ORs and 95 % CIs were estimated using multivariate logistic regression models. Participants: 20 044 Korean adults aged >= 40 years in the Health Examinees (HEXA) study, the Cardiovascular Disease Association Study (CAVAS) and the Korea Association Resource (KARE) study. Results: During median follow-ups of 4<middle dot>09, 8<middle dot>67 and 15<middle dot>67 years in the HEXA, CAVAS and KARE studies, respectively, there were a total of 7331, 786 and 1732 incident dyslipidaemia events. Ultra-processed food intake was not significantly associated with dyslipidaemia risk. Compared with < 5 %E/d, the pooled OR (95 % CI) of >= 20 %E/d of ultra-processed food intake for dyslipidaemia incidence was 1<middle dot>01 (0<middle dot>90, 1<middle dot>13; P for trend = 0<middle dot>83). There was no interaction by dyslipidaemia-related genetic variations; ORs (95 % CIs) were 1<middle dot>04 (0<middle dot>89, 1<middle dot>22; P for trend = 0<middle dot>91) and 0<middle dot>98 (0<middle dot>84, 1<middle dot>15; P for trend = 0<middle dot>72) for individuals with high- and low-polygenic scores, respectively (P for interaction = 0<middle dot>90). Conclusions: No significant association was observed between ultra-processed food intake and the overall risk of dyslipidaemia, nor in subgroups of polygenic scores for dyslipidaemia among Korean adults with low ultra-processed food intake.Y
Risk factors in self-reported dissatisfied patients implanted with various presbyopia-correcting intraocular lenses after cataract surgery
No full textBackgroundThis study aimed to investigate the self-reported dissatisfaction rates and associated risk factors among patients who underwent cataract surgery using different types of presbyopia-correcting intraocular lenses (IOLs).MethodsThis retrospective case-control study analyzed the medical records in 340 eyes from 211 cataract surgery patients with presbyopia-correcting IOLs. The analyzed IOL types included bifocal (ReSTOR (R)), trifocal (PanOptix (R)), and extended depth-of-focus (EDOF; Symfony (R)) IOLs. The rates of self-reported dissatisfaction related to vision or photic disturbances were compared between these IOLs. Various factors, including sex, age, preoperative visual acuity and refractive status, and biometric indices, were analyzed to identify potential risk factors for dissatisfaction.ResultsThe overall dissatisfaction rate was 18.5% (63/340). Among the IOL types, Symfony (R)-implanted eyes had the highest rate of near-vision dissatisfaction, while PanOptix (R)-implanted eyes showed similar proportions of photic disturbances and near-vision discomfort. The major risk factor identified for overall dissatisfaction, regardless of IOL type, was preoperative myopia, which aligns with the risk factor for near discomfort. Meanwhile, the risk factors for photic phenomena were revealed to be thinner corneal thickness and greater corneal astigmatism. By IOL types, preoperative myopia caused near-vision discomfort in Symfony (R) eyes, whereas greater corneal astigmatism and thinner corneas were linked to photic disturbances in PanOptix (R) eyes.ConclusionsIt suggests that near-vision discomfort is related to myopic factors, whereas photic disturbances are associated with ocular aberrations. The types of dissatisfaction vary depending on the designs of presbyopia-correcting IOLs.Trial RegistrationThis retrospective study adhered to the principles of the Declaration of Helsinki and was approved by the Institutional Review Board of the Seoul National University Hospital on March 13, 2023 (IRB No: 2303-025-1409).N
서리풀악기거리 내 악기판매점의 분포 특성 연구
No full textThis study explores the spatial distribution and characteristics of musical instrument stores in Seoripul Instrument Street, a cultural-commercial cluster in Seocho District, Seoul. This cluster emerged with the establishment of major cultural landmarks like the Seoul Arts Center and the Korea National University of Arts. The research examines locational patterns, operational strategies, and factors driving the clustering of these stores. Field surveys, interviews, and mapping analysis were used to analyze 88 instrument stores across three zones. Zone 1, near the Seoul Arts Center, has the highest store density. Zone 2, marked by high rents and high-rise buildings, has limited occupancy. Zone 3, with lower accessibility and visibility, has fewer stores but offers lower rent costs. A floor-level analysis shows that most stores are located on upper floors rather than ground floors, reflecting a preference for private, specialized spaces that foster trust with professional customers. The findings reveal that consumer accessibility, urban structure, and the specific needs of classical music instruments shape the spatial distribution of stores in Seoripul Instrument Street. By examining the relationship between cultural-commercial clustering and urban spatial organization, the study underscores the exclusivity and professional focus of classical music culture, contributing to the understanding of specialized urban districts.N
A Study on Improving Legislation for the Planning of Post-Disaster Temporary Housing-Based on a Legal Analysis of Cases Since 2018-
No full textThis study focused on the legislation that serves as the basis for post-disaster temporary housing plans for disaster victims. The Building Act and the Disaster Relief Act started from the Japanese legal framework and have been repeatedly revised insufficiently regarding post-disster temporary housing. The method of relief has also been established with refer ence to the current situation in Japan and continues to this day. This has become the background for the development of post-disster temporary housing with a focus on rapid supply. In Korea, temporary housing is becoming longer-term and improvements in livability are being demanded, but despite the development and demands of society, the legislation still remains in the old framework and needs to be reviewed. In Korea, in a system that prioritizes shelters in public facilities, guidelines on post-disaster temporary housing were established in 2018 and serve as the basis for planning. However, there has been insufficient research on how the guidelines have affected planning. Therefore, this study analyzed three post-disaster temporary housing cases planned after the 2018 guidelines. From the cases, the insufficient influence of the legislation on planning and the need for improvement were derived and improvement measures were proposed. The significance of this study lies in examining how domestic legislation has dealt with post-disaster temporary housing and, based on cases, deriving improvement measures that are appropriate for the domestic situation.N
Linguistic Conditions affecting L2 Learners Acquisition of Korean Case-Particle Alternation
No full textThis study examines the linguistic and L1-related factors affecting advanced L2 Korean learners acquisition of case-particle alternation, with emphasis on morphosyntactic and lexical-semantic conditions. Specifically, it analyzes Japanese L1 and Chinese L1 learners judgments of causative constructions and quotative clausal complements. In causative constructions (morphosyntactic condition), Japanese L1 learners demonstrate non-native-like performances owing to morphological incongruency with Koreans. By contrast, in cognitive clausal complements involving ergativity (lexical-semantic condition), they demonstrate native-like sensitivity, thus suggesting the facilitative role of morphological congruency. Chinese L1 learners, whose native language is devoid of a case-marking system, experience persistent difficulties with both constructions. These findings challenge the interface hypothesis, which predicts fewer difficulties in internal interfaces, and indicate that morphosyntactic phenomena may pose challenges when L1-L2 alignments are weak
Impactor shape effect on the shock mitigation behavior of metamaterial structures
No full textAuxetic metamaterial structures, characterized by their negative Poisson's ratio, have shown promising mechanical performance, particularly in shock impact scenarios. However, the complex and scenario-dependent behavior of these structures necessitates comprehensive and appropriate evaluation and verification. In this study, the shock mitigation property of an auxetic planar design in relation to the shape of the impactor surface was discussed using numerical simulation results, validated using drop testing shock experiments. Results revealed that both metamaterial shape and impactor geometry significantly influenced behavior of metamaterial response. For the plate impactor, minimal deformation at lower velocities resulted in higher peak accelerations for metamaterial configurations. Conversely for the cylindrical impactor, metamaterial structures consistently enhanced shock mitigation across all impact velocities. An Artificial Neural Network (ANN) model was developed to predict the vertical direction acceleration of the impactor by also incorporating the shape of the impactor as an evaluation parameter, in addition to the metamaterial dimensions and impact velocity. Validation with impact scenarios outside the subset of the training dataset confirmed the ANN model's accuracy, achieving at least 94% accuracy for both impactor cases, thereby offering an efficient alternative to traditional experimental and numerical simulations for studying metamaterial shock mitigation behavior.N
Farmer Managed Natural Regeneration (FMNR) Adoption and Farmers' Perceptions on Conservation in the Tsavo Dispersal Area, Kenya: Insights from the KOICA-World Vision Climate Resilience Project
No full text연구목적: 본 연구는 케냐 차보생태지역 주민을 대상으로 FMNR(Farmer Managed Natural Regeneration) 도입 여부와 이행 정도가 주민의 환경보전 및 산림복원에 대한 기대 인식, 그리고 환경보호 활동 참여에 미치는 영향을 분석한다. 이를 통해 FMNR의 지속가능한 구현과 주민들의 자발적 참여 및 연대를 위한 시사 점을 제시하고자 한다.
연구의 중요성: FMNR의 근본적 가치인 환경보전과 산림복원에 대한 인식이 실제 도입⋅이행 주체들에게 얼마나 내면화되고 개인적 가치관에 통합되었는 지를 확인함으로써 FMNR 확대 및 효과 극대화를 위한 방안을 논의한다는 점에서 의의가 있다.
연구방법론: 현지 가구 설문조사 데이터를 이용하여 FMNR 도입 및 이행 정도 가 환경보전 및 산림복원에 대한 기대 인식에 미치는 영향을 일반화된 순서형 로짓 모형(Generalized Ordered Logit)으로 분석한다. 또한, 환경보호 활동 참여 도에 미치는 영향을 다중선형회귀분석(Multiple OLS)을 통해 추정한다.
연구결과: FMNR을 도입한 가구일수록, 또 이행 정도가 높을수록 환경보전에 대한 인식이 더 긍정적이며 실제 환경보호 활동에도 더 적극적으로 참여하는 것으로 나타났다. 다만 FMNR을 도입하고 이행 정도가 높은 가구는 산림복원으로 기대할 수 있는 편익이 오히려 낮다고 인식하는 경향이 관찰되었다.
결론 및 시사점: FMNR이 성공적으로 정착 및 확산되기 위해서는 장기적인 수익 창출 체계를 제시하는 전략이 필요하다. 예컨데, 협동조합을 통한 임산물 공동판매, FMNR 기술 교육 및 이점 홍보, 소액 대출 등의 금융지원은 지역사회 구성원들이 실질적 혜택을 누릴 수 있는 방안을 마련함으로써 지속가능성을 제고할 수 있다.N
Excess Cations Alter *CO Intermediate Configuration and Product Selectivity of Cu in Acidic Electrochemical CO2 Reduction Reaction
No full textConcentrated cations are often employed to promote electrochemical CO2 reduction reaction (CO2RR) selectivity in acidic electrolytes. Here, we investigate the influence of excess cations on the *CO adsorption configuration and the product distribution of the CO2RR. Operando attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) reveals that increasing the Cs+ concentration shifts the preference of the *CO intermediate on the Cu surface from the atop (*COatop) to the bridge (*CObridge) configuration. This transition leads to a sharp decline in C-C coupling and an increase in the hydrogen evolution reaction at high Cs+ concentrations (0.7 and 1.0 M) under acidic conditions. Time-resolved SEIRAS scans show that *COatop is kinetically dominant and the proportion of *CObridge increases gradually only at high cation concentrations. Density functional theory simulations confirm that Cs+ on the Cu surface can interact electrostatically with *CO and stabilize *CObridge over *COatop on the Cu surface. The evolution of *CObridge is also observed on Ag catalysts, indicating that the effect at high concentrations is not limited to Cu. Furthermore, polymeric binders on the Cu surface mitigate these detrimental effects on the CO2RR and restore C2H4 production by preventing the cation from altering the *CO adsorption sites on the catalyst surface. This study provides new insights into the effects of cations on catalyst performance, with implications for catalyst design and operation.Y