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The RVACS is a versatile and robust safety system driven by two natural circulations: in-vessel coolant and ex-vessel air. To observe interaction between the two natural circulations, SINCRO-IT facility was designed with two different similarity laws simultaneously. Bo’ based similarity law was employed for the in-vessel, while Ishii’s similarity law for the ex-vessel excluding the radiation. Compared to the prototype, the sodium and air system, SINCRO-IT was designed with Wood’s metal and air, having 1:4 of the length reduction, and 1.68:1 of the time scale ratio. For the steady state, RV temperature limit was violated at 0.8% of the decay heat, while the sodium boiling was predicted at 1.3%. It showed good accordance with the system code, TRACE. For an arbitrary re-criticality scenario with RVACS solitary operation, sodium boiling was predicted at 25,100 s after power increase from 1.0 to 2.0%, while the system code showed 30,300. Maximum temperature discrepancy between the experiments and system code was 4.2%. The design and methodology were validated by the system code TRACE in terms of the convection, and simultaneously, the system code was validated against the simulating experiments SINCRO-IT. The validated RVACS model could be imported to further accident analysis.

In this study, three condensation models of the CUPID code, i.e., the resolved boundary layer approach (RBLA), heat and mass transfer analogy (HMTA) model, and an empirical correlation, were tested and validated against the COPAIN and CAU tests. An improvement on HMTA model was also made to use well-known heat transfer correlations and to take geometrical effect into consideration. The RBLA was a best option for simulating the COPAIN test, having mean relative error (MRE) about 0.072, followed by the modified HMTA model (MRE about 0.18). On the other hand, benchmark against CAU test (under natural convection and occurred on a slender tube) indicated that the modified HMTA model had better accuracy (MRE about 0.149) than the RBLA (MRE about 0.314). The HMTA model with wall function and the empirical correlation underestimated significantly, having MRE about 0.787 and 0.55 respectively. When using the HMTA model, consideration of geometrical effect such as tube curvature was essential; ignoring such effect leads to significant underestimation. The HMTA and the empirical correlation required significantly less computational resources than the RBLA model. Considering that the HMTA model was reasonable accurate, it may be preferable for large-scale simulations of containment.

Sedimentary ancient DNA can indicate ecosystem-wide changes. Here, the authors show association between warm phases and high diatom abundance in the Antarctic Scotia Sea, in addition to presenting ancient eukaryote sedimentary DNA spanning the last approximately 1 million years.

This manuscript presents a self-interferometric phase analysis technique for sea surface observation using a single scatterometer system. The self-interferometric phase is proposed to complement the imprecise analysis results due to the very meager signal strength measured at a high incident angle of more than 30°, which is a vulnerability of the existing analysis method using the Doppler frequency based on the backscattered signal strength. Moreover, compared to conventional interferometry, it is characterized by the phase-based analysis using consecutive signals from a single scatterometer system without any auxiliary system or channel. To apply the interferometric signal process on the moving sea surface observation, it is necessary to secure a reference target; however, this is hard to solve in practice. Hence, we adopted the back-projection algorithm to project the radar signals onto a fixed reference position above the sea surface, where the theoretical model for extracting the self-interferometric phase was derived from the radar-received signal model applying the back-projection algorithm. The observation performance of the proposed method was verified using the raw data collected at the Ieodo Ocean Research Station in Republic of Korea. In the observation result for wind velocity at the high incident angles of 40° and 50°, the self-interferometric phase analysis technique shows a better performance of a correlation coefficient of more than about 0.779 and an RMSE (root-mean-square error) of about 1.69 m/s compared to the existing method of a correlation coefficient of less than 0.62 and RMSE of more than 2.46 m/s.

A multifunctional scatterometer system and optimized radar signal processing for simultaneous observation of various physical oceanographic parameters are described in this paper. Existing observation methods with microwave remote sensing techniques generally use several separate systems such as scatterometer, altimeter, and Doppler radar for sea surface monitoring, which are inefficient in system operation and cross-analysis of each observation data. To improve this point, we integrated separate measurement functions into a single observation system by adding a measurement function of Doppler frequency to the existing system. So it enables to simultaneously measure the range and polarimetric responses of backscattering as well as movements of the sea surface. Here, the simultaneous measurement function of Doppler frequency was implemented by sampling an FMCW (frequency modulated continuous wave) radar signal as 2D raw data consisting of fast- and slow-time samples, i.e., the range and backscattering of radar target signals are analyzed from the fast-time samples while the Doppler frequency by the radar target’s movement extracts from the slow-time samples. Through the Fourier transformed-based range-Doppler signal process, distance (R), backscattering (σ°), and Doppler frequency (fD) are sequentially extracted from the 2D raw data, and a correlation to the physical oceanographic parameters is analyzed. Operability of the proposed system was examed through total 3 times of field campaigns from June 2017 to August 2020 and the observation data retrieved by the radar measurement data (R, σ°, fD) was also cross-analyzed with in-situ data: e.g., tide, significant wave height, and wind speed and direction. Differences in the comparative results as an observational accuracy are as follows. Tidal level (Root Mean Square Error 0.169 m (R)), significant wave height (RMSE 0.127 m (R), 0.362 m (σ°)), wind speed (RMSE 1.880 m/s (fD), 2.094 m/s (σ°)) and direction (18.84° (fD)).

This study addresses the challenge of accurately forecasting demand for maintenance-related spare parts of the K-X tank, influenced by high uncertainty and external factors. Deep learning models with RobustScaler demonstrate significant improvements, achieving an accuracy of 86.90% compared to previous methods. RobustScaler outperforms other scaling models, enhancing machine learning performance across time series and data mining. By collecting eight years' worth of demand data and utilising various consumption data items, this study develops accurate forecasting models that contribute to the advancement of spare parts demand forecasting. The results highlight the effectiveness of the proposed approach, showcasing its superiority in accuracy, precision, recall, and F1-Score. RobustScaler particularly excels in time series analysis, further emphasizing its potential for enhancing machine learning performance on diverse datasets. This study provides innovative techniques and insights, demonstrating the effectiveness of deep learning and data scaling methodologies in improving forecasting accuracy for maintenance spare parts demand. [ABSTRACT FROM AUTHOR]

A sea surface imaging technique for an emergency response using a ready-made frequency modulated continuous wave–synthetic aperture radar (FMCW SAR) system and its experimental results are described in this paper. The optimal range of radiowave incidence angle for sea surface imaging was analyzed by a theoretical scattering model and measurement data, and it was properly applied to the FMCW SAR system by readjusting the delayed-dechirp process. Raw data acquired through flight experiments were reconstructed to SAR image by the range-doppler algorithm. To verify the performance of the reconstructed sea surface image, dual-channel images collected by the configuration of the along-track interferometry were used, and then performance indicators such as signal attenuation, coherence, and phase difference were analyzed. Through this experimental study, it was confirmed that the ready-made FMCW SAR system without a function of the incident angle control can also conduct limited missions for maritime observation. It is possible to be an alternative resource for emergency response, in which the cases are requiring urgent maritime disaster detection and analysis.

In this paper, a novel adaptive interval type-2 fuzzy sliding mode control (AIT2FSMC) methodology is proposed based on the integration of sliding mode control and adaptive interval type-2 fuzzy control for chaotic system. The AIT2FSMC system is comprised of a fuzzy control design and a hitting control design. In the fuzzy control design, an interval type-2 fuzzy controller is designed to mimic a feedback linearization (FL) control law. In the hitting control design, a hitting controller is designed to compensate the approximation error between the FL control law and the interval type-2 fuzzy controller. The parameters of the interval type-2 fuzzy controller, as well as the uncertainty bound of the approximation error, are tuned adaptively. The adaptive laws are derived in the sense of Lyapunov stability theorem, thus the stability of the system can be guaranteed. The proposed control system compared to adaptive fuzzy sliding mode control (AFSMC). Simulation results show that the proposed control systems can achieve favorable performance and robust with respect to system uncertainties and external disturbances. [ABSTRACT FROM AUTHOR]

Cancer cells in poorly vascularized solid tumors are constantly or intermittently exposed to stressful microenvironments, including glucose deprivation, hypoxia, and other forms of nutrient starvation. These tumor-specific conditions, especially glucose deprivation, activate a signaling pathway called the unfolded protein response (UPR), which enhances cell survival by induction of the stress proteins. We have established a screening method to discover anticancer agents that could preferentially inhibit tumor cell viability under glucose-deprived conditions. Here we identify arctigenin (ARC-G) as an active compound that shows selective cytotoxicity and inhibits the UPR during glucose deprivation. Indeed, ARC-G blocked expression of UPR target genes such as phosphorylated-PERK, ATF4, CHOP, and GRP78, which was accompanied by enhanced phosphorylation of eIF2α during glucose deprivation. The UPR inhibition led to apoptosis involving a mitochondrial pathway by activation of caspase-9 and -3. Furthermore, ARC-G suppressed tumor growth of colon cancer HT-29 xenografts. Our results demonstrate that ARC-G can be served as a novel type of antitumor agent targeting the UPR in glucose-deprived solid tumors. J. Cell. Physiol. 224:33–40, 2010 © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The screening for active compounds against malignant pleural mesothelioma (MPM) cells produced by Streptomycessp. AK-AB27 resulted in the isolation of two compounds with a dodecahydrodibenzo[b,d]furan skeleton named JBIR-23 (1) and -24 (2). Their structures were established on the basis of extensive NMR and MS analyses. Compounds 1and 2exhibited cytotoxic effects against several MPM cell lines. [ABSTRACT FROM AUTHOR]

Glucose deprivation, a pathophysiological cell condition, causes up-regulation of GRP78 and induction of etoposide resistance in human cancer cells. The induction of drug resistance can be partly explained by the fact that GRP78 can block activation of caspase-7 induced by treatment with etoposide. Therefore, downregulating GRP78 expression may be a novel strategy anticancer drug development. Based on that premise, we established a screening program for anticancer agents that exhibit preferential cytotoxic activity for etoposide-resistant cancer cells under glucose-deprived conditions. We recently isolated an active compound, AR-054, from the culture broth of Streptomyces sp., which prevents stress-induced etoposide resistance in vitro. AR-054 was identified as piericidin A, a prototypical compound, by ESI-MS analysis and various NMR spectroscopic methods. Here, we showed that piericidin A suppressed the accumulation of GRP78 protein and was also highly toxic to etoposide-resistant HT-29 cells, with IC50 values for colony formation of 6.4 and 7.7 nM under 2-deoxyglucose supplemented and glucose-deprived conditions, respectively. Interestingly, piericidin A had no effect under normal growth conditions. Therefore, we suggest that piericidin A prevents up-regulation of GRP78, and exhibits cytotoxicity in glucose-deprived HT-29 cells that are resistant to etoposide. J. Cell. Physiol. 215: 243–250, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the third most common cause of cancer-related deaths in the world. Surgical intervention followed by chemotherapy remains the primary approach to treatment since colon cancers remain refractory to most chemotherapeutic agents. Based on that, we established a program to screen natural products for cytotoxic activity, employing the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay system utilizing HT-29 human colon cancer cells. During the course of our screening, we found that the methanolic extract of silkworm droppings (SDME) has cytotoxic effects on HT-29 cells. In the present study, we investigated the possible mechanisms by which SDME exerts its antiproliferative activity in HT-29 cells. As expected, SDME inhibited growth of HT-29 cells in a dose-dependent manner as assessed by the MTT reduction assay, the lactate dehydrogenase release assay, and the colony formation assay. We also investigated whether the apoptotic effects induced by SDME involve the caspase pathway using the caspase colorimetric assay. Interestingly, caspase-9 and -3, but not caspase-8, were activated in response to SDME treatment. Taken together, these results clearly indicate that the induction of apoptosis by SDME involves a mitochondrial-mediated pathway and strongly suggest that SDME may potentially be a chemotherapeutic agent for human colon cancer. [ABSTRACT FROM AUTHOR]

The feasibility of controlling the selective precipitation of pancreatic proteins was investigated using designed organic antisolvents in a drowning-out process. First, the solubility of pancreatin was measured in water−organic solutions when the organic species and their composition in the solution were varied. Due to the hydrophilicity of the proteins, solubility was rapidly reduced when the organic species fraction in the solution was increased. This reduced solubility was further amplified with a less polar organic species. Plus, the pancreatin solubility as a predictor was found to agree well with the solution polarity as a single parameter, expressed in terms of the Hildebrand solubility parameter. The precipitation of pancreatin was then carried out with various antisolvents composed of alcoholic and nonalcoholic species. The precipitation was promoted along with an antisolvent of a lower polarity, which was also functionally related to the solution polarity. The amylase, lipase, and protease proteins contained in the pancreatin displayed different precipitation behaviors depending on the polarity of the antisolvent. Thus, it was possible to selectively separate the proteins and control their composition in the precipitated pancreatin. [ABSTRACT FROM AUTHOR]

The article discusses a study regarding the isolation of JBIR-66 compound from the culture broth of tunicate-derived actinomycete, saccharopolyspora sp. SS081219JE-28. It mentions that JBIR-66 was purified with macrolactin E, gilvocarcin M, and V. The SS081219JE strain was cultured in 50 ml test tubes containing 1.0% starch and 1.0 meat extract. Moreover, the study indicates that new species of actinobacteria could produce bioactive compounds consisting of skeletal structures.

We investigated the prevalence of periauricular eczematization (PAE) in children with atopic dermatitis (AD) in Korea, and evaluated the clinical significance of the lesion in terms of its treatment in relation to a possible pathogenetic role for Staphylococcus aureus. Tentatively, PAE was classified as infraauricular and postauricular fissuring, which were observed in 62 (57.9%) and 37 (34.6%) of 107 patients, respectively. Sixty eight patients (64.5%) had infraauricular or postauricular fissures, or both, and this prevalence was significantly (p < 0.01) higher than that In controls (1.3%). Staphylococcus aureus was cultured from oozing material from infraauricular fissures in 12 of 14 patients, and topical application of erythromycin cream to the ear lesions led to faster and more definite improvement. Our study shows that PAE is a characteristic clinical manifestation of AD, probably induced by S. aureus. Topical antibiotics are worth trying for effective management of this disorder. [ABSTRACT FROM AUTHOR]

Focuses on an infant with neufibromatosis. Etiology of halo formation; Decrease in the dendrites of dermal melanocytes; Destruction of an inflammatory infiltrate by a preexisting lesion.

A new high-resolution record for the Antarctic Zone shows persistent anti-phasing of high interglacial ocean productivity and high glacial dust deposition, suggesting a close inter-hemispheric coupling of cryosphere, ocean and atmosphere.

A design parameter study is presented for the closed-loop type passive containment cooling system (PCCS) which is equipped with two heat exchangers: one installed at the inside of the containment and the other submerged in the water pool at the outside of the containment. A GOTHIC code model for PCCS performance analyses was set up and the design parameters such as the heat exchanger sizes, locations, and water pool tank volumes were analyzed to investigate the feasibility of installing this type of PCCS in PWRs like OPR-1000 being operated in Korea. We identified the size of the circulation loop and heat exchangers as major design parameters affecting the performance of PCCS. The analyses showed that the heat exchangers in the inside of the containment would be more influential on the heat removal capability of PCCS than that installed in the water pool at the outside of the containment. Hence, it was recommended to down-size the heat exchangers in the water pool to optimize PCCS without compromising its performance. Based on the parametric study, it was demonstrated that a closed-loop type PCCS could be designed sufficiently compact for installation in the available space within the containment of PWRs like OPR-1000.