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For the peaceful use of nuclear energy, materials, and technology, various methods have been developed for safeguards purposes. Among them, the In-Situ Object Counting System has demonstrated its usefulness and reliability in various nuclear material verification activities, due to its capability of operating without standard materials. In the present study, the performance of In-Situ Object Counting System for uranium quantification was evaluated using an experimental drum at KEPCO NF as well as low-level radioactive waste drums at the Korea Radioactive Waste Agency. The results showed that In-Situ Object Counting System could quantify uranium in radioactive waste drums, with a relative error ranging from −1 to −67 % compared with destructive assay results. This study also examined, using the Monte Carlo N-particle transport 6.2 code, the factors that affect uncertainty in uranium quantification: geometrical conditions, spectrum quality, heterogeneity, and the self-shielding effect. These findings could prove useful in efforts to optimize the In-Situ Object Counting System as a tool for nuclear material verification in the safeguards context.

This work investigated the most suitable type of degrader (Cu, Al or Nb) and its thickness, taking into consideration the salient aspects of concrete activation for high-purity 89Zr production by 89Y(p,n)89Zr nuclear reaction. The MCNP and FISPACT codes were used to determine the optimal degrader thickness and the radioactivity of shielding concrete by neutron activation, respectively. The results showed that the optimal thickness of the beam degraders was 1.16, 3.19, and 1.33 mm for Cu, Al, and Nb, respectively. The neutron production rate per proton and the energy and angular distributions of neutrons varied depending on the type of degrader. Considering the radioactivity of the target-room concrete and the amount of radioactive waste expected to be generated, the use of a 1.33-mm-thick Nb degrader for 89Zr production was determined to be the best choice.

The importance of fast neutron detection for nuclear safeguards purposes has increased due to its potential advantages such as reasonable cost and higher precision for larger sample masses of nuclear materials. Pulse-shape discrimination (PSD) is inevitably used to discriminate neutron- and gamma-ray- induced signals from organic scintillators of very high gamma sensitivity. The light output (LO) threshold corresponding to several MeV of recoiled proton energy could be necessary to achieve fine PSD performance. However, this leads to neutron count losses and possible distortion of results obtained by neutron multiplicity counting (NMC)-based nuclear material accountancy (NMA). Moreover, conventional PSD techniques are not effective for counting of neutrons in a high-gamma-ray environment, even under a sufficiently high LO threshold. In the present work, PSD performance (figure-of-merit, FOM) according to LO bands was confirmed using a conventional charge comparison method (CCM) and compared with results obtained by convolution neural network (CNN)-based PSD algorithms. Also, it was attempted, for the first time ever, to reject fake neutron signals from distorted PSD regions where neutron-induced signals are normally detected. The overall results indicated that higher neutron detection efficiency with better accuracy could be achieved via CNN-based PSD algorithms.

In our previous study, we proposed an integrated PG-PET-based imaging method to increase the prediction accuracy for patient dose distributions. The purpose of the present study is to experimentally validate the feasibility of the PG-PET system. Based on the detector geometry optimized in the previous study, we constructed a dual-head PG-PET system consisting of a 16 × 16 GAGG scintillator and KETEK SiPM arrays, BaSO4 reflectors, and an 8 × 8 parallel-hole tungsten collimator. The performance of this system as equipped with a proof of principle, we measured the PG and positron emission (PE) distributions from a 3 × 6 × 10 cm3 PMMA phantom for a 45 MeV proton beam. The measured depth was about 17 mm and the expected depth was 16 mm in the computation simulation under the same conditions as the measurements. In the comparison result, we can find a 1 mm difference between computation simulation and measurement. In this study, our results show the feasibility of the PG-PET system for in-vivo range verification. However, further study should be followed with the consideration of the typical measurement conditions in the clinic application.

Purpose DA-8010 is a novel muscarinic M3 receptor antagonist with significant selectivity for bladder over salivary gland in preclinical studies. We evaluated the clinical efficacy and safety of DA-8010 in overactive bladder (OAB) patients. Methods This phase 2, randomized, double-blind, parallel-group, active reference- and placebo-controlled trial was conducted at 12 centers in South Korea (NCT03566134). Patients aged ≥19 years with OAB symptoms for ≥3 months were enrolled. Three hundred six patients (30.07% male) were randomized to 12 weeks of treatment among 4 groups; 2 experimental groups (DA-8010 2.5 or 5 mg), an active reference group (solifenacin 5 mg), and a placebo group. The change from the baseline of (=∆) 24-hour frequency at 12 weeks (primary endpoint), episodes of urgency, overall/urgency urinary incontinence, average/ maximum voided volume, nocturia, and patients’ subjective responses were analyzed. Results In the full analysis set, the mean (standard deviation) [median] values for ∆ 24-hour frequency at 12 weeks were -1.01 (2.44) [-1.33] for placebo, -1.22 (2.05) [-1.33] for DA-8010 2.5 mg, and -1.67 (2.25) [-1.67] for DA-8010 5 mg; DA-8010 5 mg showed a significant decrease compared with placebo (P=0.0413). At 4 and 8 weeks, both DA-8010 2.5 mg (P=0.0391 at 4 weeks, P=0.0335 at 8 weeks) and DA-8010 5 mg (P=0.0001 at 4 weeks, P=0.0210 at 8 weeks) showed significant decrease in ∆ 24-hour frequency compared with placebo. DA-8010 5 mg achieved a significant decrease in ∆ number of urgency episodes, compared with placebo at 4 (P=0.0278) and 8 (P=0.0092) weeks. Adverse drug reactions (ADRs) were observed in 3.95% of placebo, 6.67% of DA-8010 2.5 mg, 18.42% of DA-8010 5 mg, and 17.33% of solifenacin 5 mg groups. No serious ADRs were observed in any patient. Conclusions Both DA-8010 2.5 mg and 5 mg showed therapeutic efficacy for OAB without serious ADRs. Therefore, both dosages of DA-8010 can advance to a subsequent large-scale phase 3 trial.

Abstract Background Probiotic starters can improve the flavor profile, texture, and health-promoting properties of fermented foods. Tetragenococcus halophilus is a halophilic lactic acid bacterium that is a candidate starter for high-salt fermented foods. However, the species is known to produce biogenic amines, which are associated with neurotoxicity. Here, we report a probiotic starter strain of T. halophilus, EFEL7002, that is suitable for use in high-salt fermentation. Results EFEL7002 was isolated from Korean meju (fermented soybean) and identified as T. halophilus, with 99.85% similarity. The strain is safe for use in food as it is a non-hemolytic and non-biogenic amine producer. EFEL7002 is tolerant to gastrointestinal conditions and can adhere to Caco-2 cells. This strain showed antioxidant, anti-inflammatory, and protective effects against the human gut epithelial barrier. EFEL7002 grew well in media containing 0–18% NaCl showing maximum cell densities in 6% or 12% NaCl. Conclusions T. halophilus EFEL7002 can be used as a health-promoting probiotic starter culture for various salty fermented foods.

We aimed to examine the difference in rest-activity rhythm (RAR) and light exposure rhythm (LER) between patients with mild cognitive impairment (MCI) and normal controls (NC), and to verify their relationships with cognitive functions. The neuropsychological battery was administered to participants above 50 years old. The MCI diagnosis was made according to Petersen’s criteria. Ten patients with MCI (77.90 ± 6.95 years) and eight NC (74.75 ± 5.06 years) were studied. Actigraphy (Actiwatch 2; Philips Respironics) was recorded at home for 5 days. RAR and LER variables, including interdaily stability (IS), intradaily variability (IV) and relative amplitude, were calculated using nonparametric analyses. The associations between cognitive performance and RAR and LER variables were explored using generalized linear models. There were no significant differences in RAR or LER variables between MCI and NC. There was a significant main effect of RAR-IS on the Stroop Color and Word Test (SCWT), indicating a positive relationship between RAR stability and SCWT performance. There was a significant group by RAR-IS interaction on Trail Making Test-A, indicating a negative relationship in MCI compared to NC. There was a significant group by LER-IV interaction on the Boston Naming Test, indicating a positive relationship in MCI compared to NC. There was no disruption in RAR and LER in patients with MCI. Our study showed that circadian rhythm abnormality was associated with a decline in executive function. However, circadian rhythm abnormality was not associated with declines in processing speed and language function in patients with MCI, implying an altered pathophysiology compared to NC.

Nuclear materials can be utilized not only for peaceful uses, but also for military purposes; hence, the international community has devoted itself to the control, management and safeguarding of nuclear materials. Nuclear materials are of varying degrees of usability for development of nuclear weapons. Thus, several methods for assessing the attractiveness of nuclear materials for nuclear weapons purposes have been proposed. When these methods are applied to unirradiated depleted, natural, and low-enriched uranium (DU, NU, and LEU), they are certainly classified as non-attractive nuclear materials. However, when nuclear material attractiveness is to be evaluated for potential radiological dispersal device (RDD) uses, it is required to develop a different method for the different aspects and factors. In the present study, we derived a novel method for evaluating nuclear material attractiveness for use in RDD development. To this end, the specific activity and dose coefficient were identified as the two sub-factors, and, in consideration of those, the mass causing detrimental health effects was determined to be the main factor impacting on nuclear materials attractiveness. Based on this factor, the attractiveness of unirradiated DU, NU, and LEU for RDD use was qualitatively compared with that of 137Cs.

One of the possible options for spent-fuel management in Korea is pyroprocessing, which is a process for electrochemical recycling of spent nuclear fuel. Nuclear material accountancy is considered to be a safeguards measure of fundamental importance, for the purposes of which, the amount of nuclear material in the input and output materials should be measured as accurately as possible by means of chemical analysis and/or non-destructive assay. In the present study, a neutron measurement system based on the fast-neutron energy multiplication (FNEM) and passive neutron albedo reactivity (PNAR) techniques was designed for nuclear material accountancy of a spent-fuel assembly (i.e., the input accountancy of a pyroprocessing facility). Various parameters including inter-detector distance, source-to-detector distance, neutron-reflector material, the structure of a cadmium sleeve around the close detectors, and an air cavity in the moderator were investigated by MCNP6 Monte Carlo simulations in order to maximize its performance. Then, the detector responses with the optimized geometry were estimated for the fresh-fuel assemblies with different 235U enrichments and a spent-fuel assembly. It was found that the measurement technique investigated here has the potential to measure changes in neutron multiplication and, in turn, amount of fissile material. Keywords: Nondestructive assay, Nuclear safeguards, Nuclear material accountancy, Spent-fuel assembly

The use of probiotic starters can improve the sensory and health-promoting properties of fermented foods. In this study, we developed an anti-inflammatory probiotic starter, Limosilactobacillus reuteri EFEL6901, for use in kimchi fermentation. The EFEL6901 strain was safe for use in foods and was stable under human gastrointestinal conditions. In in vitro experiments, EFEL6901 cells adhered well to colonic epithelial cells and decreased nitric oxide production in lipopolysaccharide-induced macrophages. In in vivo experiments, oral administration of EFEL6901 to DSS-induced colitis mice models significantly alleviated the observed colitis symptoms, prevented body weight loss, lowered the disease activity index score, and prevented colon length shortening. Analysis of these results indicated that EFEL6901 played a probiotic role by preventing the overproduction of pro-inflammatory cytokines, improving gut barrier function, and up-regulating the concentrations of short-chain fatty acids. In addition, EFEL6901 made a fast growth in a simulated kimchi juice and it synthesized similar amounts of metabolites in nabak-kimchi comparable to a commercial kimchi. This study demonstrates that EFEL6901 can be used as a suitable kimchi starter to promote gut health and product quality.

The use of probiotic starters can improve the sensory and health-promoting properties of fermented foods. This study aimed to evaluate the suitability of probiotic lactic acid bacteria (LAB) as a starter for kimchi fermentation. Seventeen probiotic type strains were tested for their growth rates, volatile aroma compounds, metabolites, and sensory characteristics of kimchi, and their characteristics were compared to those of Leuconostoc (Le.) mesenteroides DRC 1506, a commercial kimchi starter. Among the tested strains, Limosilactobacillus fermentum, Limosilactobacillus reuteri, Lacticaseibacillus rhamnosus, Lacticaseibacillus paracasei, and Ligilactobacillus salivarius exhibited high or moderate growth rates in simulated kimchi juice (SKJ) at 37 °C and 15 °C. When these five strains were inoculated in kimchi and metabolite profiles were analyzed during fermentation using GC/MS and 1H-NMR, data from the principal component analysis (PCA) showed that L. fermentum and L. reuteri were highly correlated with Le. mesenteroides in concentrations of sugar, mannitol, lactate, acetate, and total volatile compounds. Sensory test results also indicated that these three strains showed similar sensory preferences. In conclusion, L. fermentum and L. reuteri can be considered potential candidates as probiotic starters or cocultures to develop health-promoting kimchi products.

This prospective study aimed to evaluate whether Contralateral compensatory testicular hypertrophy (CTH) is valid as a predictive tool for a non-viable testis in children aged between 6 and 18 months, and whether CTH is affected by mini-puberty. Seventy-two testes from 60 boys aged between 6 and 18 months were categorized into three groups: 24 testes contralateral to surgically removed non-viable testes (NVTs), 24 testes contralateral to surgically corrected undescended testes (UDTs), and 24 testes from a normal controls. Contralateral testicular length and volume were measured with ultrasonography and compared among the groups. Group 1 (NVT) had a significantly longer length and larger volume than group 2 (UDT). The length and volume of each group among three developmental periods (6-10, 10-14, and 14-18 months) were also analyzed. In the controls, the length was significantly larger at 6-10 months than at 10-14 months in accordance with previously reported changes in testicular size due to the effect of "mini-puberty." The volume of controls showed a similar pattern, though without statistical significance. However, this pattern was not observed in the NVT and UDT groups. A receiver operating curve revealed that a testicular length of 16.1 mm or a volume of 0.59 ml had the highest sensitivity and specificity for predicting NVTs. The CTH was also found to be valid as a predictive tool for a NVT in children of ages 6 to 18 months, as the effect of mini-puberty appeared to be absent in the NVT and UDT groups. However, the cut-off values were less than those of previous reports. The proper cut-off level according to the age and measurement method should be applied in this developmental period.

Immersed boundary methods (IBMs) have evolved over the past 50 years from a specialized technique in biofluid dynamics and applied mathematics to a cornerstone of computational fluid dynamics. Many recent advancements in immersed boundary methods have centered on sharp-interface immersed boundary methods, which offer enhanced accuracy and fidelity for flow simulations. This paper outlines the key principles that have driven our own efforts in the development of sharp-interface immersed boundary methods over the past 25 years. We also highlight the power and versatility of these methods by showcasing a range of applications, spanning biolocomotion (i.e., swimming and flying), physiological flows, compressible aerodynamics, fluid–structure interaction (FSI), and flow-induced noise. [ABSTRACT FROM AUTHOR]

Background: Pharyngeal infection is more difficult to diagnose and treat than genital or rectal infection and can act as a reservoir for gonococcal infection. We determined the prevalence of pharyngeal gonorrhea in Korean men with urethritis and analyzed the molecular characteristics and antimicrobial susceptibility of the isolates. Methods: Seventy-two male patients with symptoms of urethritis who visited a urology clinic in Wonju, Korea, between September 2016 and March 2018 were included. Urethral and pharyngeal gonococcal cultures, antimicrobial susceptibility testing, Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST), and multiplex real-time PCR (mRT-PCR) were performed. Results: Among the 72 patients, 59 tested positive for gonococcus by mRT-PCR. Of these 59 patients, 18 (30.5%) tested positive in both the pharynx and urethra, whereas 41 tested positive only in the urethra. NG-MAST was feasible in 16 out of 18 patients and revealed that 14 patients had the same sequence types in both urethral and pharyngeal specimens, whereas two patients exhibited different sequence types between the urethra and pharynx. Of the 72 patients, 33 tested culture-positive. All patients tested positive only in urethral specimens, except for one patient who tested positive in both. All culture-positive specimens also tested positive by mRT-PCR. All isolates were susceptible to azithromycin and spectinomycin, but resistance rates to ceftriaxone and cefixime were 2.9% and 14.7%, respectively. Conclusions: The prevalence of pharyngeal gonorrhea in Korean men with gonococcal urethritis is as high as 30.5%, highlighting the need for pharyngeal screening in high-risk groups. Ceftriaxone is the recommended treatment for pharyngeal gonorrhea. [ABSTRACT FROM AUTHOR]

This study explores the characteristics of prompt literacy among learners by employing ChatGPT as a supportive tool in Korean language education, specifically analyzing the actual interaction logs between learners and ChatGPT. Over one semester, 15 Korean language learners completed three writing tasks, during which three notable characteristics of prompt literacy emerged: uniformity, discreteness, and passivity. Uniformity describes the tendency of learners to rely on limited and repetitive prompt formats, which constrain their ability to interact dynamically with AI. Discreteness reflects the lack of continuity in interactions, where exchanges with ChatGPT often appear segmented rather than connected, thus limiting deeper engagement. Passivity indicates a prevalent approach in which learners accept AI responses without critically evaluating or expanding on them, resulting in a more superficial use of ChatGPT. These findings highlight that learners tend to use ChatGPT primarily as a tool for information retrieval or translation rather than as a dynamic conversational partner, thereby underutilizing the AI's full potential. To maximize the educational impact of generative AI, there is a clear need for instructional support aimed at strengthening learners' prompt literacy skills and encouraging deeper, more interactive engagement with AI tools in language learning. [ABSTRACT FROM AUTHOR]

Soybean alleviates cognitive impairment. In our preparatory experiment, we found that dry-heat (90 °C for 30 min)-processed soybean embryo ethanol extract (hSE) most potently suppressed lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α expression in BV2 cells among dry-heat-, steaming-, and oil exclusion-processed soybean embryo ethanol extracts (SEs). Heat processing increased the absorbable soyasaponin Bb content of SE. Therefore, we investigated whether hSE and its supplement could mitigate LPS-impaired cognitive function in mice. Among dry-heat-, steaming-, and oil exclusion-processed SEs, hSE mitigated LPS-impaired cognitive function more than parental SE. hSE potently upregulated LPS-suppressed brain-derived neurotropic factor (BDNF) expression in the hippocampus, while LPS-induced TNF-α and IL-1β expression in the hippocampus and colon were downregulated. Lactobacillus gasseri NK109 additively increased the cognitive function-enhancing activity of hSE in mice with LPS-induced cognitive impairment as follows: the hSE and NK109 mix potently increased cognitive function and hippocampal BDNF expression and BDNF-positive neuron cell numbers and decreased TNF-α expression and NF-κB-positive cell numbers in the hippocampus and colon. These findings suggest that hSE and its supplement may decrease colitis and neuroinflammation by suppressing NF-κB activation and inducing BDNF expression, resulting in the attenuation of cognitive impairment. [ABSTRACT FROM AUTHOR]

Introduction: Humanized mouse models to recapitulate human biological systems still have limitations, such as the onset of lethal graft-versus-host disease (GvHD), a variable success rate, and the low accessibility of total body irradiation (TBI). Recently, mice modified with the CD47-SIRPA axis have been studied to improve humanized mouse models. However, such trials have been rarely applied in NOD mice. In this study, we created a novel mouse strain, NOD-CD47nullRag2nullIL-2rγnull (RTKO) mice, and applied it to generate humanized mice. Methods: Four-week-old female NOD-Rag2nullIL-2rγnull (RID) and RTKO mice pre-conditioned with TBI or busulfan (BSF) injection were used for generating human CD34+ hematopoietic stem cell (HSC) engrafted humanized mice. Clinical signs were observed twice a week, and body weight was measured once a week. Flow cytometry for human leukocyte antigens was performed at intervals of four weeks or two weeks, and mice were sacrificed at 48 weeks after HSC injection. Results: For a long period from 16 to 40 weeks post transplantation, the percentage of hCD45 was mostly maintained above 25% in all groups, and it was sustained the longest and highest in the RTKO BSF group. Reconstruction of human leukocytes, including hCD3, was also most prominent in the RTKO BSF group. Only two mice died before 40 weeks post transplantation in all groups, and there were no life-threatening GvHD lesions except in the dead mice. The occurrence of GvHD has been identified as mainly due to human T cells infiltrating tissues and their related cytokines. Discussion: Humanized mouse models under all conditions applied in this study are considered suitable models for long-term experiments based on the improvement of human leukocytes reconstruction and the stable animal health. Especially, RTKO mice pretreated with BSF are expected to be a valuable platform not only for generating humanized mice but also for various immune research fields. [ABSTRACT FROM AUTHOR]

This study focused on the inconsistent relationship between the fear of negative evaluation and academic procrastination in previous studies and assumed that there may be a moderating variable between the two variables. Therefore, this study aimed to verify the moderating effect of social anxiety on the relationship between the fear of negative evaluation and academic procrastination. For this purpose, a questionnaire was administered to 323 college students from 41 universities in Korea, and the data were analysed. The result showed that the fear of negative evaluation and social anxiety had significant influences on academic procrastination. The moderating effect of social anxiety on the relationship between the fear of negative evaluation and academic procrastination was significant. In particular, when social anxiety was low, the relationship between the fear of negative evaluation and academic procrastination was not significant. [ABSTRACT FROM AUTHOR]

As the Fourth Industrial Revolution continues to expand across various industries, many companies are accelerating efforts to establish smart factory-based industrial environments. A smart factory refers to an intelligent production system that maximizes efficiency and productivity by integrating digital automation into every stage of production, including design, manufacturing, quality control, and logistics. This innovative system is particularly significant in the high-precision aerospace component manufacturing industry, where the importance of meeting stringent quality standards is paramount. The high-precision aerospace component industry demands extremely high-quality standards, and to meet these requirements, precise measurements using three-dimensional (3D) measurement machines have become an essential part of the production process. Accurate data collection through 3D measurement machines plays a crucial role in ensuring product quality. However, traditional methods of data collection and management have heavily relied on manual processes, which are time-consuming, labor-intensive, and prone to human error, leading to limitations in productivity and quality control. To address these challenges, this paper proposes the design and methodology for developing a Statistical Process Control (SPC) system platform specifically tailored for the real-time automatic collection and analysis of 3D measurement data in high-precision aerospace manufacturing processes. The agent developed in this research enables the real-time automatic collection of raw data, offering significant advantages in terms of labor and time savings compared to traditional manual methods. This agent automatically compiles and analyzes data, facilitating optimized quality verification processes for high-precision aerospace component manufacturing. The collected quality data are analyzed using statistical quality control techniques specialized for 3D measurement data, allowing for continuous monitoring of product quality. Additionally, the system supports the establishment of a quality monitoring system capable of real-time response to any quality issues that may arise, significantly enhancing the efficiency of quality management. Therefore, the system proposed in this paper provides the essential technological foundation for implementing smart factories in the high-precision aerospace component manufacturing industry, with the potential to greatly improve overall productivity and quality management efficiency. This research is expected to make significant contributions to quality management in smart manufacturing environments for high-precision components. [ABSTRACT FROM AUTHOR]