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We implement machine learning regression models to predict peak pressures of primary and secondary systems, a major safety concern in Loss Of Condenser Vacuum (LOCV) accident. We selected the Multi-dimensional Analysis of Reactor Safety-KINS standard (MARS-KS) code to analyze the LOCV accident, and the reference plant is the Korean Optimized Power Reactor 1000MWe (OPR1000). eXtreme Gradient Boosting (XGBoost) is selected as a machine learning tool. The MARS-KS code is used to generate LOCV accident data and the data is applied to train the machine learning model. Hyperparameter optimization is performed using a simulated annealing. The randomly generated combination of initial conditions within the operating range is put into the input of the XGBoost model to predict the peak pressure. These initial conditions that cause peak pressure with MARS-KS generate the results. After such a process, the error between the predicted value and the code output is calculated. Uncertainty about the machine learning model is also calculated to verify the model accuracy. The machine learning model presented in this paper successfully identifies a combination of initial conditions that produce a more conservative peak pressure than the values calculated with existing methodologies.

Summary: Design of tissue-specific contrast agents to delineate tumors from background tissues is a major unmet clinical need for ultimate surgical interventions. Bioconjugation of fluorophore(s) to a ligand has been mainly used to target overexpressed receptors on tumors. However, the size of the final targeted ligand can be large, >20 kDa, and cannot readily cross the microvasculature to meet the specific tissue, resulting in low targetability with a high background. Here, we report a small and hydrophilic phenoxazine with high targetability and retention to pancreatic neuroendocrine tumor. This bioengineered fluorophore permits sensitive detection of ultrasmall (

Summary: Loss of a cell's ability to terminally differentiate because of mutations is a selected genetic event in tumorigenesis. Genomic analyses of low-grade glioma have reported recurrent mutations of far upstream element-binding protein 1 (FUBP1). Here, we show that FUBP1 expression is dynamically regulated during neurogenesis and that its downregulation in neural progenitors impairs terminal differentiation and promotes tumorigenesis collaboratively with expression of IDH1R132H. Mechanistically, collaborative action between SRRM4 and FUBP1 is necessary for mini-exon splicing of the neurospecific LSD1+8a isoform. LSD1+8a was downregulated upon loss of FUBP1 in neural progenitors, thereby impairing terminal neuronal differentiation and maturation. Reinforcing LSD1+8a expression in FUBP1-downregulated neural progenitors restored terminal differentiation and suppressed tumorigenesis; hence, LSD1+8a is an obligatory effector of FUBP1-dependent neuronal differentiation. These findings establish a direct role for FUBP1 in neuronal differentiation and also explain its tumor-suppressor function in the nervous system. : In this article, Paik and colleagues demonstrate that FUBP1 plays an indispensable role in promoting terminal differentiation of neurons and that lack of FUBP1 interferes with early-born neuronal cells exiting the cell cycle and predisposes these cells for transformation. These findings explain how FUBP1 serves uniquely as a tumor suppressor in the CNS. Keywords: neural stem cell, FUBP1, LSD1, splicing, differentiation, glioma, oligodendroglioma

Nuclear criticality safety analyses (NCSAs) considering burnup credit were performed for the GBC-32 cask. The used nuclear fuel assemblies (UNFAs) discharged from Hanbit Nuclear Power Plant Unit 3 Cycle 6 were loaded into the cask. Their axial burnup distributions and average discharge burnups were evaluated using the DeCART and Multi-purpose Analyzer for Static and Transient Effects of Reactors (MASTER) codes, and NCSAs were performed using SCALE 6.1/STandardized Analysis of Reactivity for Burnup Credit using SCALE (STARBUCS) and Monte Carlo N-Particle transport code, version 6 (MCNP 6). The axial burnup distributions were determined for 20 UNFAs with various initial enrichments and burnups, which were applied to the criticality analysis for the cask system. The UNFAs for 20- and 30-year cooling times were assumed to be stored in the cask. The criticality analyses indicated that keff values for UNFAs with nonuniform axial burnup distributions were larger than those with a uniform distribution, that is, the end effects were positive but much smaller than those with the reference distribution. The axial burnup distributions for 20 UNFAs had shapes that were more symmetrical with a less steep gradient in the upper region than the reference ones of the United States Department of Energy. These differences in the axial burnup distributions resulted in a significant reduction in end effects compared with the reference.

In this paper, we describe a computer program, iBEST (inverse Burnup ESTimator), that we developed to accurately estimate the burnup histories of spent nuclear fuels based on sample measurement data. The burnup history parameters include initial uranium enrichment, burnup, cooling time after discharge from reactor, and reactor type. The program uses algebraic equations derived using the simplified burnup chains of major actinides for initial estimations of burnup and uranium enrichment, and it uses the ORIGEN-S code to correct its initial estimations for improved accuracy. In addition, we newly developed a stable bisection method coupled with ORIGEN-S to correct burnup and enrichment values and implemented it in iBEST in order to fully take advantage of the new capabilities of ORIGEN-S for improving accuracy. The iBEST program was tested using several problems for verification and well-known realistic problems with measurement data from spent fuel samples from the Mihama-3 reactor for validation. The test results show that iBEST accurately estimates the burnup history parameters for the test problems and gives an acceptable level of accuracy for the realistic Mihama-3 problems.

Despite its numerous advantages, the aerobic granular sludge (AGS) process faces several challenges that hinder its widespread implementation. One such challenge is the requirement for high organic load ratios (OLR), which significantly impacts AGS formation and stability, posing a barrier to commercialization. In response to these challenges, this study investigates the granulation and treatment efficacy of the AGS process for treating high-concentration wastewater under various OLR and settling time. Three sequential batch reactors (R1, R2, R3) were operated at OLRs of 0.167, 0.33, and 1 kg COD/m3·day. The study focuses on analyzing key parameters including sludge characteristics, extracellular polymeric substances (EPS) content, PN/PS ratio, and microbial clusters. Results demonstrate that reducing settling time from 90 to 30 min enhances sludge settleability, resulting in a maximum 50.8 % decrease in SVI30 (from 98.1 to 122.8 mL/g to 51.9–81.3 mL/g), thereby facilitating the selection of beneficial microorganisms during granulation. Particularly, at R2, the PN/PS ratio was 4.3, and EPS content increased by 1.52-fold, leading to a 1.41-fold increase in sludge attachment. This observation suggests a progressive maturation of AGS. Additionally, analysis of microbial diversity and cluster composition highlights the influence of OLR variations on the ratios of Proteobacteria and Bacteroidetes. These findings emphasize the significant impact of SBR operational strategies on AGS process performance and biological stability, offering valuable insights for the efficient operation of future high-concentration wastewater treatment processes.

Background: Sarcopenia and muscular dystrophy are two muscle diseases. In cancer patients, cancer cachexia induces continuous weight loss and muscle loss due to the disease itself or the use of anticancer drugs. Cachexia occurs in up to 80% of cancer patients. It is recognized as a direct cause of reduced quality of life, contributing to at least 20% of cancer-associated deaths and limiting therapeutic options for cancer patients. Cancer cachexia is associated with multiple chronic or end-stage conditions and develops similarly. There are various options for the treatment of cancer cachexia, but there are still many issues to be solved. Hence, to determine its potential to overcome the muscle wasting during cancer cachexia, we studied the effect of BST204, a refined dry ginseng extract, on muscle fiber regeneration. Experimental procedure: We checked the muscle regeneration efficacy of BST204. First, BaCl2 and freeze injury models were selected to investigate muscle regeneration after BST204 administration. In addition, after inducing muscle differentiation of C2C12 cells, the efficacy of BST204 was analyzed. In this model, we analyzed the expression of the signal pathway (PI3K-AKT signal) by Western blot and imaging methods. Results and conclusion: These results showed that BST204 induced muscle fiber regeneration in BaCl2 and freeze injury models. Also, we confirmed that BST204 could regulate the PI3K/AKT signaling pathway and regulate the differentiation of C2C12 cells. These results indicate that BST204 has the potential to facilitate the skeletal muscle regeneration during muscle wasting induced by various factors including cancer cachexia.

In recent years, many methods have been investigated to improve imaging speed in photoacoustic microscopy (PAM). These methods mainly focused upon three critical factors contributing to fast PAM: laser pulse repetition rate, scanning speed, and computing power of the microprocessors. A high laser repetition rate is fundamentally the most crucial factor to increase the PAM speed. In this paper, we review methods adopted for fast PAM systems in detail, specifically with respect to light sources. To the best of our knowledge, ours is the first review article analyzing the fundamental requirements for developing high-speed PAM and their limitations from the perspective of light sources.

Background: Caring the eye from oxidative stress is very important in preventing the age-related macular degeneration (AMD), which is difficult to recover it once damaged. Particularly, the development of therapeutic anti-dry-AMD agent in a non-invasive manner is still on the horizon. Purpose: In the present study, we examined effect of gypenoside (Gyp) LXXV against dry-AMD in vitro and in vivo, to develop non-invasive anti-AMD agents based on a natural compound with anti-oxidative and anti-inflammatory activity. Study design: Gyp LXXV, a single ginseng ginsenoside compound, is orally administered to adult rabbits and mice that the dry-AMD was induced by asodium iodate or a light irradiation, respectively. The in vitro assay was performed using the retinal cells (ARPE-19) and macrophage cells (HMC-3). Methods: To evaluate anti-oxidative capability and anti-inflammable efficacy of Gyp LXXV in retinal pigment epithelial (RPE) cells, real time PCR was employed using ARPE-19 cells and HMC-3 cells. To validate physiological effects of Gyp LXXV on dry-AMD, thickness measurement of RPE, electroretinogram (ERG), optical coherence tomography (OCT), and fundus examination were employed in either light irradiation- or sodium iodate-induced animal model. Results: It exhibited substantial alleviation of damaged retinal RPE tissues, via lowering the structural damage, the reactive oxygen species (ROS) level, and inflammatory cytokines in a dose-dependent manner, without showing any side effects. In addition, ROS-induced human adult RPE cells were treated with Gyp LXXV showed a protective effect against the ROS, confirming an excellent antioxidant efficacy with no potential cytotoxicity. Conclusion: Our findings indicate that the oral route of Gyp LXXV exerts a potential therapeutic effect on dry-AMD. This work could guide the new therapeutic pathway of a phytochemical drug-based non-invasive treatment for dry-AMD in future clinical treatments.

Multispectral photoacoustic microscopy uses a wavelength-dependent absorption difference as a contrast mechanism to image the target molecule. In this paper, we present a novel multispectral pulsed fiber laser source, which selectively alternates the excitation wavelengths between green and red colors based on the stimulated Raman scattering (SRS) effect for imaging. This laser has a high pulse repetition rate (PRR) of 300 kHz and high pulse energy of more than 200 nJ meeting the real-time requirements of optical-resolution photoacoustic microscopy imaging. By switching the polarization state of the pump light and optical paths of the pump light, the operating wavelengths of the light source can be selectively alternated at the same fast PRR for any two SRS peak wavelengths between 545 and 655 nm. At 545 nm excitation wavelength, molecular photoacoustic signals from both blood vessels and gold nanorods were obtained simultaneously. However, at 655 nm, the photoacoustic signals of gold nanorods were dominant because the absorption of light by the blood vessels decreased drastically in the spectral region over 600 nm. Thus the multispectral photoacoustic system designed using the novel laser source implemented here could simultaneously monitor the time-dependent fast movement of two molecules independently, having different wavelength-dependent absorption properties at a high repetition rate of 0.49 frames per second (fps).