Search Results (14)

Background/Objectives: Computer-aided detection (CAD) systems for lung nodule detection often face challenges with 5 mm computed tomography (CT) scans, leading to missed nodules. This study assessed the efficacy of a deep learning-based slice thickness reduction technique from 5 mm to 1 mm to enhance CAD performance. Methods: In this retrospective study, 687 chest CT scans were analyzed, including 355 with nodules and 332 without nodules. CAD performance was evaluated on nodules, to which all three radiologists agreed. Results: The slice thickness reduction technique significantly improved the area under the receiver operating characteristic curve (AUC) for scan-level analysis from 0.867 to 0.902, with a p-value < 0.001, and nodule-level sensitivity from 0.826 to 0.916 at two false positives per scan. Notably, the performance showed greater improvements on smaller nodules than larger nodules. Qualitative analysis confirmed that nodules mistaken for ground glass on 5 mm scans could be correctly identified as part-solid on the refined 1 mm CT, thereby improving the diagnostic capability. Conclusions: Applying a deep learning-based slice thickness reduction technique significantly enhances CAD performance in lung nodule detection on chest CT scans, supporting the clinical adoption of refined 1 mm CT scans for more accurate diagnoses. Full article

Recently, pollution caused by an increasing amount of worldwide plastic waste has become a global problem. However, these concerns can be alleviated by the use of gamma-ray technology. Using radiation technology, plastic wastes can be converted into a variety of useful purposes presenting powerful opportunities for environmental sustainability and material innovations. Plastics are strong, durable, waterproof, lightweight, easy to mold, and recyclable. In this study, plastic aggregate modified by gamma irradiation was mixed into cement composites, and mechanical property evaluation experiments were conducted. As a result, it was confirmed that the physical performance of cement composites was improved by up to 70% in the case of using the modified plastic aggregates compared to the general plastic aggregate. Full article

Tangential-firing boilers develop large swirling fireballs by using pulverized coal and air from the corners of the burner zone. During operation, however, the boiler may experience an uneven air supply between corners; this deforms the fireball, raising various issues concerning performance and structural safety. This study investigated the characteristic boiler performance and the role of burner tilting in a 500 MWe boiler with secondary air (SA) in two corners that are up to 1.9 times larger than those in the other corners. Computational fluid dynamics simulations with advanced coal combustion sub-models were employed with the following two sets of cases: (i) six cases of actual operation to validate the modeling and (ii) sixteen cases for the parametric study of SA flow ratio and burner tilt between −15° and +26°. The results showed that the uneven SA supply deteriorated the boiler performance in various aspects and the burner tilt can be used to alleviate its impact. With a larger SA supply from the left wind box, the mass flow, heat absorption, and O₂ concentration were larger in the right half of the heat exchanger sections owing to the rotating flow. The corresponding imbalance in the reaction stoichiometry increased the peak temperature entering the tube bundles by up to 60 °C and NO emissions by 6.7% as compared with normal operations. The wall heat absorption was up to 19% larger on the right and front walls. The high burner tilt of +26° helped alleviate the impact of uneven SA supply on the heat distribution and uniformity of the flow pattern and temperature, whereas a +15° burner tilt was the least favorable. Full article

In the past few decades, there have been numerous attempts to add plastic aggregates composed of polymeric materials to cementitious composites, either as an alternative to using natural aggregates or as fillers and fibers. However, the addition of plastic aggregates often results in cementitious composites with lower mechanical performance. In this paper, we attempt to address this issue by applying gamma irradiation technology to restore the mechanical performance. We aimed to determine the optimal gamma irradiation and mixing combinations by comparing the experimental results with information summarizing the recent literature related to the use of gamma-irradiated plastic aggregates within cementitious composites. To this end, the effects of changes in the physical and chemical properties of plastics due to irradiation with gamma irradiation on the strength of cementitious composites were evaluated using irradiation doses of 25, 50, 75, and 100 kGy and various plastic materials as key parameters. In the compressive strength test, it was found that adding gamma-irradiated plastic increased the compressive strength of the cementitious composites compared to the nonirradiated plastic. This suggests that the irradiation of plastic aggregates with gamma rays is an effective method to recover some of the strength lost when plastic aggregates are added to cementitious composites. In addition, modifications in the microstructure and chemical properties of the gamma-irradiated plastic were analyzed through SEM and FT-IR analysis, which allowed the determination of the strength enhancement mechanism. The results of this study show the possibility of the state-of-the-art performance improvement method for using plastic aggregate as a substitute for natural aggregate, going further from the plastic performance improvement technology for limited materials and radiation dose presented in previous studies. Full article

We investigated the effects of Cissus verticillata leaf extract (CVE) on a high-fat diet (HFD)-induced obesity and memory deficits. Male mice (5 weeks of age) were fed vehicle (distilled water), or 30, 100, or 300 mg/kg of CVE once a day for 8 weeks with an HFD. Treatment with CVE resulted in lower body weight and glucose levels in a concentration- and feeding time-dependent manner. LDL cholesterol and triglyceride levels were significantly lower in the CVE-treated HFD group than in the vehicle-treated HFD group. In contrast, high-density lipoprotein cholesterol levels did not show any significant changes. Lipid droplets and ballooning were reduced depending on the concentration of CVE treatment compared to the HFD group. Treatment with CVE ameliorated the increase in glucagon and immunoreactivities in the pancreas, and novel object recognition memory was improved by 300 mg/kg CVE treatment compared to the HFD group. More proliferating cells and differentiated neuroblasts were higher in mice treated with CVE than in vehicle-treated HFD-fed mice. Brain-derived neurotrophic factor (BDNF) levels were significantly decreased in the HFD group, which was facilitated by treatment with 300 mg/kg CVE in hippocampal homogenates. These results suggest that CVE ameliorates HFD-induced obesity and memory deficits in mice, associated with increased BDNF levels in the hippocampus. Full article

This paper proposes a method to embed and extract a watermark on a digital hologram using a deep neural network. The entire algorithm for watermarking digital holograms consists of three sub-networks. For the robustness of watermarking, an attack simulation is inserted inside the deep neural network. By including attack simulation and holographic reconstruction in the network, the deep neural network for watermarking can simultaneously train invisibility and robustness. We propose a network training method using hologram and reconstruction. After training the proposed network, we analyze the robustness of each attack and perform re-training according to this result to propose a method to improve the robustness. We quantitatively evaluate the results of robustness against various attacks and show the reliability of the proposed technique. Full article

Conventional methods for etiologic diagnoses of acute gastroenteritis (AGE) are time consuming and have low positive yield leading to limited clinical value. This study aimed to investigate quality improvements in patient management, antibiotic stewardship, and in-hospital infection transmission prevention using BioFire^® FilmArray^® Gastrointestinal Panel (GI Panel) in children with acute diarrhea. This was a prospective study recruiting children < 19 years old with new onset diarrhea during the study period, and a matched historical cohort study of children diagnosed with AGE during the 4 years prior. Patients in the prospective cohort underwent stool testing with GI Panel and conventional methods. A total of 182 patients were included in the prospective cohort, of which 85.7% (n = 156) had community-onset and 14.3% (n = 26) had hospital-onset diarrhea. A higher pathogen positivity rate for community-onset diarrhea was observed by the GI Panel (58.3%, n = 91) compared to conventional studies (42.3%, n = 66) (p = 0.005) and historical cohort (31.4%, n = 49) (p < 0.001). The stool tests reporting time after admission was 25 (interquartile range, IQR 17–46) hours for the GI Panel, and 72 (IQR 48–96) hours for the historical cohort (p < 0.001). A significant reduction in antibiotic use was observed in the prospective cohort compared to historical cohort, 35.3% vs. 71.8%; p < 0.001), respectively. Compared to the GI Panel, norovirus ICT was only able to detect 4/11 (36.4%) patients with hospital-onset and 14/27 (51.8%) patients with community-onset diarrhea. The high positivity rate and rapid reporting time of the GI Panel had clinical benefits for children admitted for acute diarrhea, especially by reducing antibiotic use and enabling early adequate infection precaution and isolation. Full article

In the present study, we examined the effects of Cissus verticillata leaf extracts (CVE) against hydrogen peroxide (H₂O₂)- and ischemia-induced neuronal damage in HT22 cells and gerbil hippocampus. Incubation with CVE produced concentration-dependent toxicity in HT22 cells. Significant cellular toxicity was observed with >75 μg/mL CVE. CVE treatment at 50 μg/mL ameliorated H₂O₂-induced reactive oxygen species formation, DNA fragmentation, and cell death in HT22 cells. In addition, incubation with CVE significantly mitigated the increase in Bax and decrease in Bcl-2 induced by H₂O₂ treatment in HT22 cells. In an in vivo study, the administration of CVE to gerbils significantly decreased ischemia-induced motor activity 1 d after ischemia, as well as neuronal death and microglial activation 4 d after ischemia, respectively. CVE treatment reduced the release of interleukin-1β, interleukin-6, and tumor necrosis factor-α 6 h after ischemia. Furthermore, CVE treatment significantly ameliorated ischemia-induced phosphorylation of c-Jun N-terminal kinase, extracellular signal-regulated kinase 1/2, and p38. These results suggest that CVE has the potential to reduce the neuronal damage induced by oxidative and ischemic stress by reducing the inflammatory responses and phosphorylation of MAPKs, suggesting that CVE could be a functional food to prevent neuronal damage induced by ischemia. Full article

Junctional proteins in cerebrovascular endothelial cells are essential for maintaining the barrier function of the blood-brain barrier (BBB), thus protecting the brain from the infiltration of pathogens. The present study showed that the potential therapeutic natural compound auraptene (AUR) enhances junction assembly in cerebrovascular endothelial cells by inducing antioxidant enzymes and the mitochondrial unfolded protein response (mtUPR). Treatment of mouse cerebrovascular endothelial cells with AUR enhanced the expression of junctional proteins, such as occludin, zonula occludens-1 (ZO-1) and vascular endothelial cadherin (VE-cadherin), by increasing the levels of mRNA encoding antioxidant enzymes. AUR treatment also resulted in the depolarization of mitochondrial membrane potential and activation of mtUPR. The ability of AUR to protect against ischemic conditions was further assessed using cells deprived of oxygen and glucose. Pretreatment of these cells with AUR protected against damage to junctional proteins, including occludin, claudin-5, ZO-1 and VE-cadherin, accompanied by a stress resilience response regulated by levels of ATF5, LONP1 and HSP60 mRNAs. Collectively, these results indicate that AUR promotes resilience against oxidative stress and improves junction assembly, suggesting that AUR may help maintain intact barriers in cerebrovascular endothelial cells. Full article

Lithium metal batteries are considered “rough diamonds” in electrochemical energy storage systems. Li-metal anodes have the versatile advantages of high theoretical capacity, low density, and low reaction potential, making them feasible candidates for next-generation battery applications. However, unsolved problems, such as dendritic growths, high reactivity of Li-metal, low Coulombic efficiency, and safety hazards, still exist and hamper the improvement of cell performance and reliability. The use of functional separators is one of the technologies that can contribute to solving these problems. Recently, functional separators have been actively studied and developed. In this paper, we summarize trends in the research on separators and predict future prospects. Full article

We investigated the effects of pyridoxine deficiency on ischemic neuronal death in the hippocampus of gerbil (n = 5 per group). Serum pyridoxal 5′-phosphate levels were significantly decreased in Pyridoxine-deficient diet (PDD)-fed gerbils, while homocysteine levels were significantly increased in sham- and ischemia-operated gerbils. PDD-fed gerbil showed a reduction in neuronal nuclei (NeuN)-immunoreactive neurons in the medial part of the hippocampal CA1 region three days after. Reactive astrocytosis and microgliosis were found in PDD-fed gerbils, and transient ischemia caused the aggregation of activated microglia in the stratum pyramidale three days after ischemia. Lipid peroxidation was prominently increased in the hippocampus and was significantly higher in PDD-fed gerbils than in Control diet (CD)-fed gerbils after ischemia. In contrast, pyridoxine deficiency decreased the proliferating cells and neuroblasts in the dentate gyrus in sham- and ischemia-operated gerbils. Nuclear factor erythroid-2-related factor 2 (Nrf2) and brain-derived neurotrophic factor (BDNF) levels also significantly decreased in PDD-fed gerbils sham 24 h after ischemia. These results suggest that pyridoxine deficiency accelerates neuronal death by increasing serum homocysteine levels and lipid peroxidation, and by decreasing Nrf2 levels in the hippocampus. Additionally, it reduces the regenerated potentials in hippocampus by decreasing BDNF levels. Collectively, pyridoxine is an essential element in modulating cell death and hippocampal neurogenesis after ischemia. Full article

High-resolution meteorological information is essential for attaining sustainable and resilient cities. To elucidate high-resolution features of surface and air temperatures in high-rise building blocks (BBs), a 3-dimensional BB meteorological observation experiment (BBMEX) campaign was designed. The campaign was carried out in a central commercial area in Seoul during a heat-wave event period (5−6 August) in 2019. Several types of fixed instrument were deployed, a mobile meteorological observation cart (MOCA) and a vehicle were operated periodically. The surface temperature was determined to be strongly dependent on the facial direction of a building, and sunlit or shade by surrounding obstacles. Considerable increases in surface temperature on the eastern facades of buildings before noon, on horizontal surfaces near noon, and on the western facades in the afternoon could provide more energy in BBs than over a flat surface. The air temperatures in the BB were higher than those at the Seoul station by 0.1−2.2 °C (1.1−1.9 °C) in daytime (night-time). The MOCA revealed that the surface and air temperatures in a BB could be affected by many complex factors, such as the structure of the BBs, shades, as well as the existence of facilities that mitigate heat stresses, such as ground fountains and waterways. Full article

Background: The addition of the adjuvant dexmedetomidine to a nerve block improves the quality of the block and reduces perioperative opioid consumption. The aim of this study was to assess the effect of dexmedetomidine as an adjuvant for the thoracic paravertebral block (TPVB) in postoperative pain control after video-assisted thoracoscopic surgery (VATS). Methods: Sixty-six males, aged 15–40 years, with spontaneous pneumothorax scheduled for VATS wedge resection were enrolled. Following surgery, ultrasound-guided TPVB was performed on the T3 and T5 levels with 30 mL of 0.5% ropivacaine, plus adjuvant dexmedetomidine 50 μg or normal saline. The primary outcome was cumulative fentanyl consumption at 24 h. Pain severity, the requirement for additional rescue analgesics, hemodynamic variations, and side effects were also evaluated. Results: Median postoperative cumulative fentanyl consumption at 24 h was significantly lower in the dexmedetomidine group (122.6 (interquartile range (IQR) 94.5–268.0) μg vs. 348.1 (IQR, 192.8–459.2) μg, p-value = 0.001) with a Hodges–Lehman median difference between groups of 86.2 (95% confidence interval (CI), 4.2–156.4) mg. Coughing numeric rating scale (NRS) was lower in the dexmedetomidine group at postoperative 2, 4, 8, and 24 h. However, resting NRS differed significantly only after 4 h postoperative. Conclusions: Dexmedetomidine as an adjunct in TPVB provided effective pain relief and significantly reduced opioid requirement in VATS. Full article

In this paper, we reviewed the existing literature on the fabrication of nanocomposites based on cellulose and cellulose nanocrystals (CNCs), and analyzed their dispersion mechanism with respect to their use in the field of construction. First, the existing literature on CNC-based nanocomposites that exhibit the physical and chemical properties of nanocellulose and CNCs was reviewed. Next, keeping the use of these nanocomposites in the field of construction in mind, we determined the optimal mechanical method for their dispersion as an alternative to the currently used harmful chemical techniques. To this end, we evaluated the dispersibility of colloidal CNCs using two dispersion methods: magnetic stirring (for stirring times of 60 min, 120 min, and 180 min) and high-pressure dispersion (at pressures of 345 × 10⁵ Pa, 1035 × 105 Pa, and 1587 × 10⁵ Pa, and one to three dispersion passes). The optimal dispersion conditions were determined by analyzing the size and zeta potential of the CNC particles. It was found that the difference in the average diameter was reduced by approximately 76% at 1587 × 10⁵ Pa during high-pressure dispersion. Full article