ScienceWatch@KIOST
Not a member yet
29648 research outputs found
Sort by
지난 40년간 동아시아 주변해 표층 수온 장기 변동: 온난화기, 정체기, 재가속기
No full text본 연구는 1982–2022년 41년 동안 동아시아 주변해의 표층 수온의 장기 변동을 조사하고, 그 기작과 주요 태평양 기후 모드와의 연관성을 평가하였다. 분석 기간 동안 표층 수온의 장기 변동은 (1) 온난화기(1982–1998), (2) 정체기(1998–2011), (3) 재가속기(2011–2022)로 특징지어졌다. 선행연구는 온난화기와 정체기에서 동아시아 겨울 몬순에 따른 표층 열속 변동이 수온 변동의 주요 기작임을 보였으나, 재가속기는 수온 증가 속도가 41년 평균(0.26 °C/10년)의 약 3배(0.83 °C/10년)에 달함에도 기작이 충분히 이해되지 않았다. 이를 이해하기 위해 재가속기(2011–2022)를 대상으로 GLORYS12v1 해양 재분석을 이용한 혼합층 열수지 분석을 수행하였다. 그 결과, 재가속기 동안 세 해역 모두에서 표층 수온 상승에는 표층 열속보다 해양 변동의 기여가 더 컸다. 황해·동중국해와 동해에서는 바람응력 컬이 강제한 지형류와 연관된 수평 온난 이류와 양의 연직 확산 아노말리가 표층수온 상승을 지지하였고, 일본 남쪽 해역에서는 쿠로시오 경로의 대사행(2018–2022)으로 인한 해류 변동이 수평 온난 이류를 강화하였다. 또한 태평양 10년주기 진동(PDO)과 북태평양 환류 진동(NPGO)과의 상관을 비교한 결과, 온난화기에는 PDO와 음의·NPGO와 양의 상관성이 나타났으나 재가속기에는 상관 계수가 반전되었다. 이러한 결과는 최근 10여 년 동안 동아시아 주변해 표층 수온 급상승이 과거에 비해 그 기작과 태평양 기후 모드와의 상관 모두 다르다는 것을 시사한다.2
Biomechanical Parameters Estimation for Real-Time Gait Analysis Using a Compact Radar Sensor
No full textCompact radar sensors for Internet of Things applications can be used to analyze indoor human gait characteristics. Conventional human gait analysis methods typically involve generating two-dimensional (2D) high-resolution time-frequency images and employing image-processing techniques to estimate gait parameters of a walking human. However, these computations can be resource-intensive for the compact radar sensors. To address this problem, we propose a new scheme for estimating gait parameters. Our method has four significant contributions: 1) utilization of one-dimensional phase modulation in a radar echo for efficient gait-parameters estimation, as opposed to relying on 2D time-frequency images; 2) decomposition of micro phase modulations corresponding to the torso or pelvis and lower body parts (e.g., knee, tibia, and ankle) using dedicated filtering techniques to mitigate the interference between body components; 3) compensation for effects of nonlinear macro phase modulation caused by whole-body movements; and 4) robust estimation of gait parameters including time-varying radial velocity, gait rate, step length, and the height of the lower body. In experiments performed using a 5.8 GHz continuous-wave Doppler radar, we observed that the proposed scheme can perform efficient and robust gait parameter estimation of an indoor human walking.11Nsciescopu
Composition for skin improvement containing abalone viscera extract
No full text본 발명은 피부장벽 강화 및 보습을 위한 전복 내장 추출물과 가수분해물의 제조 방법 및 이에 의해 제조
한 조성물에 관한 것으로, 본 발명의 전복 내장 초음파 추출물 및 Protamex 가수분해물은 각질형성세포에
서의 히알루론산 함량을 증가시키고, 피부장벽 및 밀착연접과 관련된 단백질을 조절하여 피부 보습 및 장
벽 강화에 효능을 나타내었다. 또한 섬유아세포에서의 콜라겐 합성 유전자를 증가시켜 피부 보습 효능을
나타내어 천연 화장품 소재로 활용이 가능하다
A New Record of Intertidal Sea Anemone, Anthopleura asiatica (Anthozoa: Hexacorallia: Actiniaria: Actiniidae), from Korea
No full textThe genus Anthopleura, one of the most species-rich taxon belonging to family Actiniidae, primarily is abundant in the intertidal zone and shallow subtidal waters. In 2022, a previously unrecorded species of Anthopleura was discovered during a survey of the intertidal regions of Ulleungdo. Specimens were later collected from Chujado in 2023 and Udo in 2024 on Jeju Island. This unrecorded species has been identified as Anthopleura asiatica through an examination of its external anatomy and cnidae, as well as comparisons of mitochondrial 16S rRNA and COIII sequences with those of related species. This study reports that five species of the genus Anthopleura have been documented in Korean waters to date.22Ykc
Climatological Atlas of Temperature and Salinity for the Northeast Asian Seas
No full textThis study describes a monthly Atlas for the Northeast Asian Seas 2023 (ANAS23) with a 1/10° horizontal resolution and 73 vertical levels. For ANAS23, over 1.6 million hydrographic profiles were analyzed, utilizing a simple kriging interpolation technique, which considers data density and their covariance at each grid point, along with a profile stabilizing method to minimize damage to water-mass structures. Comparison of ANAS23 with previously published atlases, repeated sectional observations, and satellite-based geostrophic current fields reveals that the ANAS23 provides reliable descriptions of the spatial distribution of water masses, currents, thermohaline fronts, and mesoscale eddies while avoiding spike-shape noises, vertical instabilities, and artificial waters, particularly over large-topographic features. The ANAS23 could be utilized as a baseline to assess the dynamic state of climatological mean fields and their changes under evolving climates. The fact that uncertainty among atlases is still apparent, particularly in a region of scarce observations, calls for a collaborative international effort to collect qualified hydrographic observations for a better-performing regional atlas, thus improving predictive skills for future climate.11Ysciescopu
Enhancing galactose utilization and ethanol production in Saccharomyces cerevisiae via MIG1 and COX9 gene deletion using CRISPR-Cas9 with Eucheuma denticulatum hydrolysate
No full textThis study aimed to enhance ethanol production by increasing the galactose consumption rate of recombinant Saccharomyces cerevisiae CEN-PK2 strains, using the CRISPR-Cas9 system from the hydrolysate of the red macroalgae Eucheuma denticulatum. A concentration of 27.7 g/L of monosaccharides was obtained by thermal acid hydrolysis with 10% (w/v) biomass and 300 mM nitric acid at 121 ℃ for 90 min. More monosaccharide (42.0 g/L) was obtained from subsequent enzymatic saccharification using 20 U/mL of commercial enzyme for 72 h. The ethanol fermentation and galactose uptake rate were compared with those of the wild-type strain of S. cerevisiae CEN-PK2, the COX9- and/or MIG1-gene-deleted strains, and the galactose-adapted strain. A similar glucose consumption rate was observed for all tested strains. However, the ΔMIG1 strain exhibited an enhanced galactose consumption and ethanol yield compared to the ΔCOX9 strain and the control. Furthermore, the strain with a double deletion of COX9 and MIG1 (ΔCOX9ΔMIG1) exhibited an enhanced galactose uptake and ethanol production (31.5 g/L, 0.46 g/g yield, and 0.33 g/L/h productivity). An increase in the transcription levels of the GAL regulatory genes was also observed in the ΔCOX9ΔMIG1 strain. This research could significantly impact future energy development and climate change mitigation by enhancing bioenergy efficiency and expanding its industrial applications.11Nsciescopu
Valorization of fishery byproducts: Large-scale production of olive flounder functional protein ingredients and their effects on muscle regeneration
No full textUse of olive flounder byproducts, which constitute nearly 50 % of the total fish mass, offers a promising strategy for maximizing protein-rich resources. In this study, we optimized a Prozyme 2000P® enzyme-assisted olive flounder byproduct hydrolysate (OFBP) for large-scale production using response surface methodology and evaluated its efficacy in muscle-atrophy models. The final OFBP exhibited 87.5 % protein content, with over 60 % of peptides under 700 Da, promoting high bioavailability and absorption. In vitro, OFBP (300 µg/mL) enhanced de novo protein synthesis in murine C2C12 myotubes by more than two-fold compared with the untreated control (p < 0.05). In a zebrafish model of dexamethasone-induced muscle atrophy, 1 % OFBP supplementation restored up to 80 % of normal activity levels and significantly increased muscle cross-sectional area relative to atrophic controls (p < 0.05). Lipidomic analysis further revealed that dexamethasone-associated elevations in ceramide and sphingomyelin were downregulated by OFBP, indicating a protective effect on sphingolipid metabolism. Taken together, these findings demonstrate that enzymatic hydrolysis of fish byproducts can yield a nutritionally rich ingredient that not only mitigates muscle atrophy through enhanced protein synthesis but also modulates lipid homeostasis. This work highlights OFBP as a sustainable, functional food candidate for supporting muscle health and addressing waste-utilization needs.11Nsciescopu
Shipping-related air pollution at Busan Port: The unceasing threat of black carbon
No full textBusan Port ranks among the top ten most air-polluted ports globally, yet the chemical characteristics of its air pollution, specifically the compositions and sources of aerosols, including black carbon (BC) have not been thoroughly studied. To assess the emission characteristics, four comprehensive air monitoring campaigns were conducted seasonally from fall 2020 to summer 2021. While mass concentrations of aerosol chemical species analyzed using the high-resolution time-of-flight aerosol mass spectrometer showed significant seasonal variations (3.6–11.4 µg·m−3), BC exhibited persistent concentrations throughout all seasons (1.9–2.2 µg·m−3). On average, BC constituted a staggering 26.5 % of the total non-refractory sub-micron aerosol mass concentrations. A positive matrix factorization model used to identify organic aerosol (OA) sources revealed six sources: two hydrocarbon-like OA, three oxygenated OA, and one biomass burning OA. Most of these sources were associated with shipping-related emissions at Busan Port. Spatial analysis of the elemental carbon revealed higher concentrations in port areas (1.2–1.5 µg·m−3) and surrounding areas (0.6–1.0 µg·m−3), compared to other urban cities (0.5–0.6 µg·m−3). This observation suggests that carbonaceous particles, along with persistent shipping-related OA emissions, are likely to disperse and impact air quality in adjacent urban areas, potentially posing health hazards.11Nsciescopu
Effects of high-volume limestone powder substitution on hydration and mechanical–microstructural development of low-carbon cement pastes: Simulation and experiment
No full textThis study investigated the effects of limestone powder (LP) substitution on the hydration and mechanical–microstructural evolutions of low-C cement pastes, prepared by varying the C2S content between 21.9 % and 57.2 % using developed cement hydration simulations based on CEMHYD3D and experimental validations. Higher calcium silicate hydrate (C-S-H) contents and lower calcium hydroxide (CH) contents were observed in low-C cement pastes with LP when compared with those in normal cement pastes with LP after 7 days of casting. LP substantially increased the overall degrees of hydration of low-C cement pastes by providing nucleation sites for the formations of C-S-H and CH recognized by scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM-EDS); however, LP substitution led to lower compressive strength (CS) owing to the lower cement content. Substitution of 10 % LP afforded a CS comparable to that of plain cement paste, and a composition of 30 % LP, 40 % C2S, and 18.7 % tricalcium silicate was identified as the optimal composition based on eco-efficiency and energy efficiency indices. Pastes with this optimal composition exhibited even higher CSs than that of ordinary Portland cement-based paste at 90 days; moreover, their total embodied CO2 emissions and energy consumptions were significantly low, highlighting the potentials of these pastes for sustainable and eco-friendly applications in construction. Additionally, this study offers insights into the relationship between the microstructures and mechanical properties of low-C cement pastes substituted with LP, and the developed model is very useful for the design of environmentally friendly low-C cement pastes.11Nsciescopu
Method for purifying livestock manure and producing biomass using Arthrospira sp.
No full text본 발명은 아스로스피라 속(Arthrospira sp.)을 이용한 축산분뇨의 정화 및 바이오매스의 생산 방법에 관한 것으로, 축산분뇨 액비를 미세조류인 아스로스피라 속의 배양 배지로 이용하여 축산분뇨의 정화를 달성함과 동시에 가축사료로 활용할 수 있는 바이오매스를 생산하는 방법을 제공한다