Search

This study thoroughly investigated the diet composition and feeding habits of black rockfish, Sebastes inermis along the Yeosu Coast, South Korea. The stomach content of S. inermis was dominated by shrimp (Acetes japonicus and Crangon hakodatei) and brachyura (Charybdis bimaculata and Charybdis japonica). Shrimp was the dominant prey throughout the seasons, with an increase in fish consumption observed during autumn. Predator size and sampling period influenced the average degree of stomach fullness in black rockfish; however, the significance of fish as prey increased with increasing size. Dietary overlap analysis demonstrated a high overlap among smaller size classes and a low overlap between smaller and larger size classes. The results of this study indicate that black rockfish are specialist predators of shrimp.

Background Clinical data for bacterial coinfection of the lower respiratory tract in patients with nontuberculous mycobacterial pulmonary disease (NTM-PD) are scarce. This study aims to assess the prevalence of bacterial coinfection and clinical features in NTM-PD patients. Methods This retrospective study screened 248 patients with NTM-PD who underwent bronchoscopy between July 2020 and July 2022, from whom newly diagnosed NTM-PD patients were analyzed. Bacterial culture using bronchial washing fluid was performed at the time of NTM-PD diagnosis. Results In the 180 patients (median age 65 years; 68% female), Mycobacterium avium complex (86%) was the most frequent NTM isolated. Bacterial coinfections were detected in 80 (44%) patients. Among them, the most common bacterium was Klebsiella pneumoniae (n=25/80, 31.3%), followed by Pseudomonas aeruginosa (n=20/80, 25%) and Staphylococcus aureus (n=20/80, 25%). Compared with NTM-PD patients without bacterial coinfections, patients with bacterial coinfections showed more frequent extensive lung involvement (33% vs. 1%, p

Pyroprocess technology has been considered as a fuel cycle option to solve the spent fuel accumulation problems in Korea. The Korea Atomic Energy Research Institute, Daejeon, Korea has been studying pyroprocess technology, and the conceptual design of an engineering-scale pyroprocess facility, called the Reference Engineering-scale Pyroprocess Facility, has been performed on the basis of a 10 ton heavy metal throughput per year. In this paper the concept of Reference Engineering-scale Pyroprocess Facility is introduced along with its safety requirements for the protection of facility workers, collocated workers, the off-site public, and the environment. For the identification of safety structures, systems, and components and/or administrative controls, the following activities were conducted: (1) identifying hazards associated with operations; (2) identifying potential events associated with these hazards; and (3) identifying the potential preventive and/or mitigative controls that reduce the risk associated with these accident events. This study will be used to perform a safety evaluation for accidents involving any of the hazards identified, and to establish safety design policies and propose a more definite safety design.

Pyroprocess technology has been considered as a fuel cycle option to solve the spent fuel accumulation problems in Korea. The Korea Atomic Energy Research Institute has been studying pyroprocess technology, and the conceptual design of an engineering-scale pyroprocess facility, called the Advanced Fuel Cycle (AFC) facility, has been performed on the basis of a 10tHM throughput per year. In this paper, the concept of the AFC facility was introduced, and its safety evaluations were performed. For the safety evaluations, anticipated accident events were selected, and environmental safety analyses were conducted for the safety of the public and workers. In addition, basic radiation shielding safety analyses and criticality safety analyses were conducted. These preliminary safety studies will be used to specify the concept of safety systems for pyroprocess facilities, and to establish safety design policies and advance more definite safety designs.

Abstract The field of high-bandwidth holography has been extensively studied over the past decade. Orbital angular momentum (OAM) holography, which utilizes vortex beams with theoretically unbounded OAM modes as information carriers, showcases the large capacitance of hologram storage. However, OAM holography has been limited to a single wavelength, restricting its potential for full-color holography and displays. In this study, we propose wavelength and OAM multiplexed holography that utilizes the multiple dimensions of light—wavelength and OAM—to provide a multi-color platform that expands the information capacity of holographic storage devices. The proposed wavelength-OAM multiplexed holography is physically realized by a metasurface, the state-of-the-art optical element consisting of an array of artificially engineered nanostructures. Hydrogenated silicon meta-atoms, the constituents of the metasurface, are engineered to possess wavelength selectivity by tailoring the dispersion of polarization conversion. These meta-atoms are used to encode the calculated OAM-preserved phase maps based on our design. The sampling grid of the phase map is rotated by 45°, which effectively suppress higher-order diffraction, providing a great strategy for achieving large field-of-view (FOV) holography. We successfully demonstrate six holographic images that are selectively reconstructed under the illumination of light with specific wavelengths (λ = 450, 635 nm) and topological charges (l = -2, 0, 2), without high-order diffraction. Our work suggests that ultrathin meta-holograms can potentially realize ultrahigh-bandwidth full-color holography and holographic video displays with large FOV.

BackgroundThe brown croaker, Miichthys miiuy, is an economically important fish species in Korean waters. Research on the spawning ecology of M. miiuy in Korea has primarily focused on specimens from the southwestern waters, assessing parameters, such as spawning season and mature body length through histological examination. However, a comprehensive histological analysis across various body sizes during the spawning season is imperative to accurately ascertain these factors, as well as for efficient resource management amidst potential environmental variations. Therefore, this study was undertaken to investigate the spatiotemporal distribution and reproductive biology of M. miiuy in the southwestern waters of Korea.MethodsMonthly changes in gonadal maturity stages, gonadosomatic index (GSI), egg diameter, and fecundity were analyzed. Additionally, total length at sexual maturity at 50%, 75%, and 97.5%, as well as the sex ratio, were determined.ResultsM. miiuy, captured using offshore gillnets and stow nets, exhibited a seasonal migration pattern: a winter presence near Jeju Island, followed by a northward movement in spring, a summer shift to the shallow waters of Shinan, and an autumnal migration to the waters around Jeju Island for overwintering. The overall female-to-male sex ratio was 1:0.8. GSI values peaked in September and August for both sexes; however, microscopic analysis of gonadal tissue revealed a spawning period from July to September 2023, with the primary spawning season for the entire population occurring in August and September. The fork length at 50% maturity was 57.4 cm for females and 54.6 cm for males.ConclusionOverall, these results suggest an earlier shift in the spawning period of brown croakers in the southwestern waters of Korea compared to past observations. This shift is potentially attributable to higher water temperatures, increased resource levels, and alterations in the species composition of major prey items in the spawning grounds. Further research is imperative for a comprehensive understanding of the factors influencing the reproductive ecology of this important fish species.

The use of renewable energy, particularly solar and wind power, is increasing, but it is necessary to alleviate the variation of such resources, a key drawback of using renewable energy. In this context, gas turbines capable of fast startup and rapidly changing power following a load have attracted considerable attention. Nevertheless, enhancing the operational flexibility of gas turbines is crucial to ensure their stable operation under various conditions. Several studies have attempted to enhance the flexible operating capabilities, by examining the operational stability assurance under a variety of conditions and life cycle increases by changing the operating conditions. This paper proposes a new gas turbine configuration and operating strategy in which a sub-compressor is used to increase the ramp rate and mitigate the thermal load of the turbine blades. The performance and dynamic behavior of the novel gas turbine was simulated using an in-house program based on the gas path analysis. Specifically, a sub-compressor with an inter-cooler was used to cool the coolant from 398 °C to 300 °C, which increased the gas turbine power by 1.3 MW and efficiency by 0.4%p compared to the conventional gas turbine. In addition, when applying a new operating strategy during the ramp-up phase, a part of coolant air was injected into the combustor to suppress the maximum turbine inlet temperature by 15 °C compared to the conventional gas turbine. As a result, the ramp rate could be doubled (from 18.75 to 37.5 %/min) by alleviating the fluctuations of hot gas temperature in the ramp-up phase.

Abstract Background Remimazolam is safe and effective for moderate sedation during flexible bronchoscopy, but its safety and efficacy during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) remains undetermined. The REST trial (NCT06275594) will be a prospective randomized study of remimazolam in patients undergoing EBUS-TBNA with conscious sedation. The primary aim is to evaluate whether remimazolam is safe and effective for moderate sedation during EBUS-TBNA compared to real-world midazolam and on-label midazolam. Methods The REST trial will recruit 330 patients from four university hospitals with mediastinal lesions suspected of being lung cancer who are eligible for EBUS-TBNA under moderate sedation. The participants will be randomized into groups using remimazolam, real-world midazolam, and on-label midazolam (US prescribing information dosage) to perform EBUS-TBNA for procedural sedation. The primary endpoint will be procedural success using composite measures. Discussion The REST trial will prospectively evaluate the efficacy and safety of remimazolam during EBUS-TBNA under moderate sedation. It will provide information for optimizing sedation modalities and contribute to practical benefits in patients undergoing EBUS-TBNA. Trial registration ClinicalTrials.gov (NCT06275594). Prospectively registered on 15 February 2024.

Abstract Metalenses are instruments that manipulate waves and have exhibited remarkable capabilities to date. However, an important hurdle arises due to the severe hampering of the angular response originating from coma and field curvature aberrations, which result in a loss of focusing ability. Herein, we provide a blueprint by introducing the notion of a wide field-of-hearing (FOH) metalens, designed particularly for capturing and focusing sound with decreased aberrations. Employing an aberration-free planar-thin metalens that leverages perfect acoustic symmetry conversion, we experimentally realize a robust wide FOH capability of approximately 140∘ in angular range. Moreover, our metalens features a relatively short focal length, enabling compact implementation by reducing the aperture-to-hearing plane distance. This is beneficial for space-efficient source-tracking sound sensing. Our strategy can be used across various platforms, potentially including energy harvesting, monitoring, imaging, and communication in auditory, ultrasonic, and submerged environments.

This study aimed to investigate sway parameters and physical activity level of the age/gender-matched older adults with osteoporosis faller and nonfaller patients. By examining these factors, our objective was to understand how these faller and nonfaller groups with osteoporosis differed particularly in terms of balance capabilities and their impact on physical activity levels. We recruited 24 patients with osteoporosis: 12 who reported a fall within a year before recruitment (fallers) and 12 without falls (nonfallers). Given the close association between biochemical markers of musculoskeletal health such as serum calcium, parathyroid hormone (PTH), Vitamin D, and renal function, we compared these markers in both groups. As a result, elderly individuals with osteoporosis and with a history of falls within the preceding year indicated significantly higher sway velocity (P = 0.012*), sway area (P

This study focuses on the Yeosu Coast, a critical ecological and economic zone on the Korean Peninsula. We conducted a comprehensive analysis of fish data obtained from daily set nets for the period of 2008–2022 (excluding 2017) to investigate variations in fish composition and community structure over a 15-year period. The catches were characterized by a prevalence of warm-water fish species, reflecting the temperate and subtropical character of the Yeosu Coast. The total catch during the study period was 3210.8 tonnes, with 2010 and 2016 registering the highest and lowest catches, respectively. Our analysis identified sea surface temperature as a primary factor correlated with these changes in species composition. The two dominant species, Scomberomorus niphonius (Cuvier, 1832) and Engraulis japonicus Temminck et Schlegel, 1846 together accounted for a remarkable 78.9% of the total catch. Notably, the Shannon–Weaver diversity index values were lower in 2015 than in 2008, indicating potential shifts in the community structure. Our analysis identified sea surface temperature as the most dominant factor that influenced these changes in species composition. Furthermore, we highlight the significant threats posed by climate change and the increasing number of jellyfish challenging fisheries on the Yeosu Coast. These threats have the potential to result in diminished set-net catches and declining biodiversity within this valuable ecosystem. Our findings underscore the importance of monitoring and addressing these ecological shifts to ensure the long-term sustainability of Yeosu Coast fisheries.

A compact mmWave phased array antenna module (PAAM) with wide beamwidth radiators to ensure seamless mmWave communication is proposed in this article. Unlike the typical PAAM consisting of patch-type elements with limited half power beamwidth (HPBW) around 90°, the proposed PAAM is configured by balanced multipole elements with extended HPBW in both E- and H-planes. Due to the extended HPBW of the proposed antenna element, the proposed PAMM can steer main beams for wider angles with lower side lobe levels. First, a single mmWave wide HPBW antenna element was fabricated and verified at 28 GHz, showing the measured HPBW of 148.3° and 141.3° in E- and H- planes, respectively. The measured HPBW of the proposed antenna showed more than 96% inrease in both planes, comparing with the conventional patch at 28 GHz. Moreover, $1\times 4$ PAAM was fabricated by integrating the antenna array directly with a 4-channel beamforming IC to further verify the mmWave communications at 28 GHz with minimized blind spots. With 64-QAM over-the-air (OTA) test, the proposed PAAM showed the measured error vector magnitude (EVM) less than 7.1% at ±75° ranges while the conventional patch-based PAAM showed the measured EVM of 27.8% at ±75°.

Understanding the feeding ecology of anchovies in the southern waters of Korea is crucial for improving ecosystem management. However, to date, few studies have examined seasonal changes in the diet of Pacific anchovy, Engraulis japonicus Temminck et Schlegel, 1846, in Korean waters, with the majority of these focusing on the larval and adult stages. The presently reported study provides updates on the feeding habits of E. japonicus off the southern coast of Korea. We analyzed 347 individuals. One-way analysis of similarity was performed to evaluate the differences in diet composition among size classes and seasons of E. japonicus, and correspondence analysis was conducted using the matrix of the percentage by number (%N) data for prey with occurrence of less than 10% to determine the distribution of prey across all size classes and each season. The diet of E. japonicus was investigated according to season and four size classes. The fork length of these specimens ranged from 5.4 to 14.1 cm. A total of 55 prey taxa of varying sizes between 0.33 mm (diatom Coscinodiscus spp.) and 5.8 mm (fish larvae) were recorded. Anchovies were exclusively planktivorous, and copepods were the most common prey, comprising 82.1% of the identified food items and 84.3% of anchovy stomach contents analyzed. However, their occurrence and abundance varied according to season and Pacific anchovy size class. According to the percentage of the index of relative importance (%IRI), the most important prey items were the copepods Calanus sinicus (48.0%), Paracalanus orientalis (31.7%), bivalve larvae (5.8%), Ditrichocorycaeus affinis (4.2%), and calanoid copepods (2.4%). Analysis of similarities and similarity percentage analysis indicated that a distinct diet of Pacific anchovy in the southern waters of Korea is potentially driven by differences in hydrological conditions. Correspondence analysis revealed that anchovies had the most significant impact on the differences between size classes. The results deepen our understanding of prey species diversity and intraspecific food competition off the southern coast of Korea.

Abstract Background The study aimed to identify the influential factors required to prepare landslide vulnerability maps and establish disaster prevention measures for mountainous areas with forest roads. The target area is Sancheok-myeon, Chungju-si, where several landslides have occurred in a narrow area of approximately 3 km × 4 km. As the area has the same rainfall and vegetation conditions, the influences of the physico-mechanical characteristics of the soil in accordance with compaction and topographic characteristics could be analyzed precisely. Methods Geological surveying, sampling, and laboratory testing assessed landslide risk in the study area, and data including unit weight, specific gravity, porosity, water content, soil depth, friction angle, cohesion, slope angle, profile/plan curvature, TWI were obtained. Preprocessing and screening such as min-max normalization and multicollinearity were conducted for the data in order to eliminate overestimation of each factor’s effectiveness. The influence of each factor was analyzed using logistic regression (LR), structural equation modeling (SEM), extreme gradient boosting (XGBoost), and light gradient boosting machine (LightGBM). Results All methods showed that soil depth has the greatest impact on landslide occurrence. Friction angle, slope angle, and porosity were also selected as influential factors, although each method ranked them slightly differently. Topographic factors, such as plan curvature, profile curvature, and the topographic wetness index, had minimal influence. This appears to be because landslides near forest roads are more affected by how well compaction was performed during banking than by the concave or convex shape of the slope. This study presents analysis results for an area with the same rainfall and vegetation conditions; therefore, the analysis of the influence of the physico-mechanical characteristics of the soil and topography was more precise than when comparing landslides occurring in different regions. Our results may be helpful in preparing landslide vulnerability maps.

Abstract This study investigated the anatomical details of the axillary and radial nerves in 50 upper limbs from 29 adult formalin-embalmed cadavers, and ten fresh upper limbs. The focus was on understanding the course, division, and ramifications of these nerves to improve treatment of shoulder dysfunction caused by axillary nerve damage. The axillary nerve divided anteriorly and posteriorly before passing the quadrangular space in all specimens, with specific distances to the first ramifications. It was found that the deltoid muscle's clavicular and acromial parts were always innervated by the anterior division of the axillary nerve, whereas the spinous part was variably innervated. The longest and thickest branches of the radial nerve to the triceps muscles were identified, with no statistically significant differences in fiber numbers among triceps branches. The study concludes that nerve transfer to the anterior division of the axillary nerve can restore the deltoid muscle in about 86% of shoulders, and the teres minor muscle can be restored by nerve transfer to the posterior division. The medial head branch and long head branch of radial nerve were identified as the best donor options.

Background:. Falls after orthopaedic surgery can cause serious injuries, which lengthen hospital stays and increase medical expenses. This has prompted hospitals to implement various fall-prevention protocols. The aims of this study were to determine the incidence of in-hospital falls after spine surgery, to analyze the overall risk factors, to discern factors that have a major influence on falls, and to evaluate the effectiveness of the fall-prevention protocol that we implemented. Methods:. This was a retrospective, single-center study including patients who underwent spine surgery from January 2011 to November 2021 at the National Health Insurance Service Ilsan Hospital (NHISIH) in Goyang, Republic of Korea. Reported falls among these patients were examined. Patient demographics; surgery type, date, and diagnosis; and fall date and time were evaluated. Results:. Overall, 5,317 spine surgeries were performed, and 128 in-hospital falls were reported (overall incidence: 2.31%). From the multivariable analyses, older age and American Society of Anesthesiologists (ASA) score were identified as independent risk factors for in-hospital patient falls (multivariable adjusted hazard ratio [aHR] for age 70 to 79 years, 1.021 [95% confidence interval (CI), 1.01 to 1.031]; for age ≥80 years, 1.035 [1.01 to 1.06]; and for ASA score of 3, 1.02 [1.01 to 1.031]). Similar results were seen in the subgroup who underwent primary surgery. Within 2 weeks following surgery, the highest frequency of falls occurred at 3 to 7 days postoperatively. The lowest fall rate was observed in the evening (6 to 10 p.m.). Morbidities, including rib, spine, and extremity fractures, were recorded for 14 patients, but none of these patients underwent operative treatment related to the fall. The NHISIH implemented a comprehensive nursing care service in May 2015 and a fall protocol in May 2017, but the annual incidence rate did not improve. The fall rate was higher after thoracolumbar surgeries (2.47%) than after cervical surgeries (1.20%). Moreover, a higher fall rate was observed in thoracolumbar cases with a greater number of fusion levels and revision spine surgeries. Conclusions:. Patients with advanced age, more comorbidities, a greater number of fusion levels, and revision surgeries and who are female are more vulnerable to in-hospital falls after spine surgery. Novel strategies that target these risk factors are warranted. Level of Evidence:. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Nonreciprocity plays a fundamental role in governing direction‐dependent asymmetric wave propagation. Previous approaches to nonreciprocity involve ferrite‐based devices with bulky systems. Herein, the controlled synthesis of a space–time modulation (STM) metamaterial for enhanced nonreciprocity using machine learning (ML) is investigated. The design of STM metamaterial poses great challenges due to the nonlinear nature of time‐periodic Floquet harmonics, which are inefficiently handled in traditional methods such as numerical optimization. To deal with the challenge, an ML approach is proposed that learns from the accumulated training data using the guided objective function and generates high‐quality designs by leveraging the learned features. This approach first trains a residual neural network (ResNet) to learn the nonlinear relationships between the STM parameters and nonreciprocal responses. The trained ResNet achieves a high testing accuracy, with 96.7% of the 9000 instances having a mean square error less than 0.6 × 10−4. For the synthesis of STM metamaterial, a customized Wasserstein generative adversarial network (WGAN) is proposed, which leverages the discovered nonlinearity and synthesizes large‐scale datasets using small computational costs. The histogram obtained using 90 000 data samples shows that WGAN generates designs with an average normalized nonreciprocity of 0.83, four times higher than the measured data.

Abstract Background This randomized controlled clinical trial compared the effects of platelet-rich fibrin (PRF) and concentrated growth factor (CGF) on early bone healing after endodontic microsurgery. Methods Eighteen patients with an isolated periapical lesion 0.05). However, no significant difference was observed between the PRF and CGF groups. At the six-month follow-up, no significant differences were observed between the groups. Conclusions These results suggested that PRF and CGF promote early bone healing after endodontic microsurgery.

Background and Objectives: Many risk factors for postoperative C5 palsy (PC5P) have been reported regarding a “cord shift” after a posterior approach. However, there are few reports about shoulder traction as a possible risk factor of anterior cervical surgery. Therefore, we assessed the stretched nerve roots when shoulder traction was applied on cadavers. Materials and Methods: Eight cadavers were employed in this study, available based on age and the presence of foramen stenosis. After dissecting the sternocleidomastoid muscle of the cadaver, the shoulder joint was pulled with a force of 2, 5, 8, 10, 15, and 20 kg. Then, the stretched length of the fifth nerve root was measured in the extra-foraminal zone. In addition, the same measurement was performed after cutting the carotid artery to accurately identify the nerve root’s origin. After an additional dissection was performed so that the superior trunk of the brachial plexus could be seen, the stretched length of the fifth and sixth nerve roots was measured again. Results: Throughout the entire experiment, the fifth nerve root stretched out for an average of 1.94 mm at 8 kg and an average of 5.03 mm at a maximum force of 20 kg. In three experiments, the elongated lengths of the C5 nerve root at 8 kg and 20 kg were 1.69/4.38 mm, 2.13/5.00 mm, and 0.75/5.31 mm, respectively, and in the third experiment, the elongated length of the C6 nerve root was 1.88/5.44 mm. Conclusions: Although this was a cadaveric experiment, it suggests that shoulder traction could be the risk factors for PC5P after anterior cervical surgery. In addition, for patients with foraminal stenosis and central stenosis, the risk would be higher. Therefore, the surgeon should be aware of this, and the patient would need sufficient explanation.

In this paper, a high gain circularly-polarized antenna array with a flat panel structure for low Earth orbit (LEO) satellite communication systems is proposed. This new CP structure can efficiently achieve high directivity and can easily be integrated with beamforming ICs (BFIC) when designing an antenna module, resulting in a good candidate for Ka-band satellite communications. Furthermore, the proposed FPAA can easily be extended to a larger scale array from a base unit in a 2 × 2 sub-array structure. Each sub-array is configured by four high-gain planar segmented antenna (PSA) elements with a sequentially rotating arrangement, where a single 4-channel BFIC can drive CP radiation. Unlike previously reported PSA elements that have limited CP performance, the proposed PSA-CP configuration adopts additional conductors and ground-via structures to further improve the CP gain, axial-ratio (AR), and cross-polarization (XPD) characteristics. To verify the performance of the proposed PSA-CP, a 2 × 2 left-hand circular polarization (LHCP) sub-array was fabricated at 28 GHz and tested with a BFIC. The measured 10-dB impedance and 3-dB AR bandwidths of the proposed 2 × 2 array were 13.92% and 12.5%, respectively. In addition, the measured peak gain was 15.2 dBic at 28.5 GHz with an XPD level of less than 15 dB.

Background: Patients who require initial venoarterial extracorporeal membrane oxygenation (VA ECMO) support may need to undergo veno-arteriovenous ECMO (VAV ECMO) conversion. However, there are no definitive criteria for conversion to VAV ECMO. We report 9 cases of VAV ECMO at Gyeongsang National University Changwon Hospital, Gyeongsang National University College of Medicine. Methods: Of 158 patients who received ECMO support between January 2017 and June 2019, 82 were supported by initial VA ECMO. We retrospectively reviewed the medical records of 9 patients (7 men and 2 women; age, 53.1±19.4 years) who had differential hypoxia and required VAV ECMO support. Percutaneous transaortic catheter venting was used to detect the differential hypoxia. Results: Among the 82 patients who received VA ECMO support, 9 (10.9%) had differential hypoxia and required conversion to VAV ECMO support. The mean time from VA ECMO support to VAV ECMO support and the mean duration of the VAV support were 2.1±2.2 days and 1.9±1.5 days, respectively. The average peak inspiratory pressure before and after VAV ECMO application was 23.89±3.95 cmH2O and 20.67±5.72 cmH2O, respectively, decreasing by an average of 3.2±3.5 cmH2O (p=0.040). The PaO2/FiO2 ratio was kept below 100 mm Hg in survivors and non-survivors for 116±65.4 and 250±124.9 minutes, respectively (p=0.016). Six patients underwent extracorporeal cardiopulmonary resuscitation, of whom 4 survived (67%). The overall survival rate of patients who underwent conversion from VA ECMO to VAV ECMO was approximately 56%. Conclusion: Rapid detection of differential hypoxia is required when VA ECMO is applied, and efficient conversion to VAV ECMO may be critical for patient survival.

Background. Distinct bacterial strains may affect the prognosis of patients with chronic respiratory diseases. However, little is known about the clinical significance of respiratory bacteria in patients with chronic pulmonary aspergillosis (CPA), a progressive and debilitating disease caused by Aspergillus spp. Objectives. This study aimed to analyze data obtained from CPA patients and their sputum or bronchial washing samples and investigate the prevalence and composition of respiratory bacteria and clinical implications. Patients and Methods. We retrospectively reviewed the data of patients diagnosed with CPA between March 2019 and February 2023 in a tertiary referral hospital. We assessed the clinical characteristics and overall and pneumonia-specific survival rates of patients with CPA based on the presence of bacteria. Results and Conclusions. We included 142 patients with CPA. The most commonly identified bacteria were Klebsiella pneumoniae (22.5%), followed by Pseudomonas aeruginosa (21.8%) and Escherichia coli (4.2%). Patients with isolated bacteria had a higher prevalence of older age, female sex, diabetes, and a history of extrathoracic malignancy than those without isolated bacteria (P=0.024,0.013,0.021,and 0.034, respectively). Furthermore, over a median follow-up of 11 (4–21) months, the pneumonia-specific mortality rate was 13.4% (19/142), which was higher in patients with isolated bacteria than in those without (P=0.045, log-rank test). Particularly, patients with the presence of P. aeruginosa had a significantly higher mortality rate from pneumonia than those without the presence of P. aeruginosa (adjusted hazard ratio, 3.34; P=0.015). In conclusion, CPA patients with isolated bacteria, especially P. aeruginosa, showed higher mortality rates due to pneumonia. Performing tests to identify bacteria in the lower respiratory tract of patients with CPA may be helpful in predicting future prognosis. Further studies are required to validate these findings in diverse ethnic groups.

Abstract Metasurfaces can modulate light with periodically arranged subwavelength scatterers, and they can generate arbitrary wavefronts. Therefore, they can be used to realize various optical components. In particular, metasurfaces can be used to realize lenses, so-called metalenses. In the last decade, metalenses have been actively studied and developed. In this review, we firstly introduce the fundamental principles of metalenses in terms of materials, phase modulation method, and design method. Based on these principles, the functionalities and the applications can consequently be realized. Metalenses have a much larger number of degrees of freedom compared with that of existing refractive or diffractive lenses. Thus, they afford functionalities such as tunability, high numerical aperture, and aberration correction. Metalenses with these functionalities can be applied in various optical systems such as imaging systems and spectrometers. Finally, we discuss the future applications of metalenses. Graphical Abstract

The aim of this study was to investigate to what extent PD affects the ability to walk, respond to balance perturbations in a single training session, and produce acute short-term effects to improve compensatory reactions and control of unperturbed walking stability. Understanding the mechanism of compensation and neuroplasticity to unexpected step perturbation training during walking and static stance can inform treatment of PD by helping to design effective training regimens that remediate fall risk. Current rehabilitation therapies are inadequate at reducing falls in people with Parkinson’s disease (PD). While pharmacologic and surgical treatments have proved largely ineffective in treating postural instability and gait dysfunction in people with PD, studies have demonstrated that therapy specifically focusing on posture, gait, and balance may significantly improve these factors and reduce falls. The primary goal of this study was to assess the effectiveness of a novel and promising intervention therapy (protective step training – i.e., PST) to improve balance and reduce falls in people with PD. A secondary goal was to understand the effects of PST on proactive and reactive feedback responses during stance and gait tasks. Multiple-baseline, repeated measures analyses were performed on the multitude of proactive and reactive performance measures to assess the effects of PST on gait and postural stability parameters. In general, the results indicate that participants with PD were able to use experiences with perturbation training to integrate and adapt feedforward and feedback behaviors to reduce falls. The ability of the participants with PD to adapt to changes in task demands suggests that individuals with PD could benefit from the protective step training to facilitate balance control during rehabilitation.

Abstract This study analyzed the expression of growth‐related genes of olive flounder, Paralichthys olivaceus, fed a low‐fish meal (FM) diet to investigate the replacement of the FM diet in the field. The expression of growth hormone (GH)/insulin‐like growth factor (IGF) axis genes in the brain/pituitary/liver and plasma hormone concentrations were measured. A basal experimental diet was formulated using 63% FM and 12% soybean meal as the primary protein sources, and then two other diets were made by replacing 20% and 30% of the FM with soy protein concentrate, tankage meal, and poultry by‐products meal. Each diet was fed to duplicate groups of juvenile flounder (150 ± 3.0 g) twice a day. After 20 weeks, the plasma growth‐related hormone concentrations were similar between the control and FM20 groups. Moreover, GH/IGF axis gene mRNA expression in the brain/pituitary/liver was similar between the control and FM20 groups. Immunoblotting of muscle and liver showed the same pattern. This study showed the utility of replacing 20% of the FM diet and supports the possibility of field application.

In 1945, atomic bombs were dropped on Hiroshima and Nagasaki. Approximately 70 000 Koreans are estimated to have been exposed to radiation from atomic bombs at that time. After Korea’s Liberation Day, approximately 23 000 of these people returned to Korea. To investigate the long-term health and hereditary effects of atomic bomb exposure on the offspring, cohort studies have been conducted on atomic bomb survivors in Japan. This study is an ongoing cohort study to determine the health status of Korean atomic bomb survivors and investigate whether any health effects were inherited by their offspring. Atomic bomb survivors are defined by the Special Act On the Support for Korean Atomic Bomb Victims, and their offspring are identified by participating atomic bomb survivors. As of 2024, we plan to recruit 1500 atomic bomb survivors and their offspring, including 200 trios with more than 300 people. Questionnaires regarding socio-demographic factors, health behaviors, past medical history, laboratory tests, and pedigree information comprise the data collected to minimize survival bias. For the 200 trios, whole-genome analysis is planned to identify de novo mutations in atomic bomb survivors and to compare the prevalence of de novo mutations with trios in the general population. Active follow-up based on telephone surveys and passive follow-up with linkage to the Korean Red Cross, National Health Insurance Service, death registry, and Korea Central Cancer Registry data are ongoing. By combining pedigree information with the findings of trio-based whole-genome analysis, the results will elucidate the hereditary health effects of atomic bomb exposure.

Abstract We used smartphone technology to differentiate the gait characteristics of older adults with osteoporosis with falls from those without falls. We assessed gait mannerism and obtained activities of daily living (ADLs) with wearable sensor systems (smartphones and inertial measurement units [IMUs]) to identify fall-risk characteristics. We recruited 49 persons with osteoporosis: 14 who had a fall within a year before recruitment and 35 without falls. IMU sensor signals were sampled at 50 Hz using a customized smartphone app (Lockhart Monitor) attached at the pelvic region. Longitudinal data was collected using MoveMonitor+ (DynaPort) IMU over three consecutive days. Given the close association between serum calcium, albumin, PTH, Vitamin D, and musculoskeletal health, we compared these markers in individuals with history of falls as compared to nonfallers. For the biochemical parameters fall group had significantly lower calcium (P = 0.01*) and albumin (P = 0.05*) and higher parathyroid hormone levels (P = 0.002**) than nonfall group. In addition, persons with falls had higher sway area (P = 0.031*), lower dynamic stability (P

Abstract Objectives The association between the chorda tympani nerve (CTN) and atresiaplasty has not been investigated. This study aimed to describe the course of the CTN observed during atresiaplasty for congenital aural atresia (CAA) and explore the feasibility of CTN preservation. Methods In this retrospective study, six consecutive patients who underwent atresiaplasty in a tertiary academic center were included. The course of the tympanic segment of the CTN and its preservation feasibility were evaluated. Atresiaplasty was performed using an anterior approach. The average Jahrsdoerfer score was 8.7 points (range, 8–9 points). Results The CTN was located in the atretic plate in all patients. It emerged from an average of 5.6 mm (range, 5.2–6.1) inferior to the incus buttress and crossed the middle ear in an anterior–superior direction. The distance between the neck of the malleus and the CTN varied in the absence of the malleus handle. However, when the malleus handle developed, the CTN passed between the incus and the malleus handle. The CTN was preserved in two of the six patients. They had a Jahrsdoerfer score of 9 and grade I microtia. Conclusion The CTN was located in the atretic plate, emerging from an average distance of 5.6 mm inferior to the incus buttress. The incus buttress might serve as a good anatomical landmark to identify and preserve the CTN. CTN preservation is feasible in atresiaplasty candidates with a Jahrsdoerfer score of 9 and auricular deformity of grade I. Level of Evidence 4.

Patients with lumbar spinal stenosis (LSS) may experience neuropathic symptoms, such as back pain, radiating pain, and neurogenic claudication. Although the long-term outcomes of both nonsurgical and surgical treatments are similar, surgery may provide shortterm benefits, including improved symptoms and lower risk of falling. Decompression is mainly used for surgical treatment, and depending on the decompression degree and associated instability, combination therapy may be given. Minimally invasive surgery has been demonstrated to produce excellent results in the treatment of LSS. Thus, an approach aimed at understanding the overall pathophysiology and treatment methods of LSS is expected to have a better therapeutic effect.

Abstract Background Environmental exposure to benzene and toluene is a suspected risk factor for metabolic disorders among the general adult population. However, the effects of benzene and toluene on blood lipid profiles remain unclear. In this study, we investigated the association between urinary blood lipid profiles and metabolites of benzene and toluene in Korean adults. Methods We analyzed the data of 3,423 adults from the Korean National Environmental Health Survey Cycle 3 (2015–2017). We used urinary trans,trans-muconic acid (ttMA) as a biomarker of benzene exposure, and urinary benzylmercapturic acid (BMA) as an indicator of toluene exposure. Multivariate logistic regression analyses were performed to explore the association between blood lipid profiles and urinary metabolites of benzene and toluene. Additionally, we examined the linear relationship and urinary metabolites of benzene and toluene between lipoprotein ratios using multivariate regression analyses. Results After adjusting for covariates, the fourth quartile (Q4) of ttMA [odds ratio (OR) (95% confidence interval, CI = 1.599 (1.231, 2.077)] and Q3 of BMA [OR (95% CI) = 1.579 (1.129, 2.208)] were associated with an increased risk of hypertriglyceridemia. However, the Q4 of urinary ttMA [OR (95% CI) = 0.654 (0.446, 0.961)] and Q3 of urinary BMA [OR (95% CI) = 0.619 (0.430, 0.889)] decreased the risk of a high level of low-density lipoprotein cholesterol (LDL-C). Higher urinary ttMA levels were positively associated with the ratio of triglycerides to high-density lipoproteins [Q4 compared to Q1: β = 0.11, 95% CI: (0.02, 0.20)]. Higher urinary metabolite levels were negatively associated with the ratio of low-density lipoprotein to high-density lipoprotein [Q4 of ttMA compared to reference: β = -0.06, 95% CI: (-0.11, -0.01); Q4 of BMA compared to reference: β = -0.13, 95% CI: (-0.19, -0.08)]. Conclusion Benzene and toluene metabolites were significantly and positively associated with hypertriglyceridemia. However, urinary ttMA and BMA levels were negatively associated with high LDL-C levels. These findings suggest that environmental exposure to benzene and toluene disrupts lipid metabolism in humans.

3D depth sensing with structured light enables simultaneous imaging of multiple objects, but has limited field of view and low efficiency. Here, the authors demonstrate 3D imaging with scattered light from a metasurface composed of periodic supercells, covering a 180° field of view with a high-density dot array.

Abstract Boron neutron capture therapy (BNCT) has been attracting interest as a new radiation modality for cancer therapy because it can selectively destroy cancer cells while maintaining the healthy state of surrounding normal cells. Many experimental trials have demonstrated significant BNCT treatment efficacy using neutron beams from research reactors. However, nuclear reactor technology cannot be scaled to sites in hospitals delivering patient treatment. Therefore, compact accelerator-based neutron sources that could be installed in many hospitals are under development or have even been commissioned at many facilities around the world. In Korea, a radio-frequency (RF) linac-based BNCT (A-BNCT) facility is under development by DawonMedax (DM). It provides the highly efficient production of an epithermal neutron beam with an optimized neutron energy spectrum range of 0.1~10 keV. With a 2-mA 10-MeV proton beam from the accelerator, the irradiation port epithermal neutron flux is higher than 1 × 109 n/cm2⋅s. Comprehensive verification and validation of the system have been conducted with the measurement of both proton and neutron beam characteristics. Significant therapeutic effects from BNCT have been confirmed by DM in both in vitro and in vivo non-clinical trials. Further, during exposure to epithermal neutrons, all other unintended radiation is controlled to levels meeting International Atomic Energy Agency (IAEA) recommendations. Recently, the Korean FDA has accepted an investigational new drug (IND) and the first-in-human clinical trial of BNCT is now being prepared. This paper introduces the principles of BNCT and accelerator-based neutron sources for BNCT and reports the recent advances of DM A-BNCT facility which is the main part of this paper.

In order to maintain the performance of a fuel cell vehicle, it is essential to maintain a constant temperature of the stack. Therefore, it is very important to distribute the optimal coolant flow rate to each major component under very diverse and rapidly changing dynamic operating conditions. The part responsible for this is a five-way electric coolant valve. Therefore, this study aims to investigate transient dynamic flow characteristics of the fluid flow through a five-way electric coolant valve (PCCV: Penta-Control Coolant Valve). To achieve this goal, this paper attempts a three-dimensional dynamic simulation of the fluid flow through the valve using a commercial CFD solver with moving mesh technique to consider flow inertia and dynamic flow in the opening and closing stages of the ball valve rotating motion. The dynamic flow characteristics and the thermal mixing inside the PCCV ball valve during the opening and closing stages are analyzed. It was found that the discrepancies between dynamic and steady-state simulations are remarkable when fluxes with different levels of enthalpy and momentum flow into the PCCV, leading to strong flow interference and flow inertia, while the discrepancies are relatively small at low rotation speed and weak flow interference. Subsequently, the effect of the dynamic flow characteristics of the valve on the dynamic thermal mixing characteristics at two different ball valve rotation speeds and rotation directions are investigated. It was found that the dynamic flow and thermal mixing characteristics inside the PCCV are greatly affected by the rotation speed, rotation direction, and degree of flow interference between fluxes. It also helps design better coolant control strategies and improves the FCEV thermal management system.

Echocardiography is a medical examination that uses ultrasound to assess and diagnose the structure and function of the cardiac. Through the use of ultrasound waves, this examination allows medical professionals to create visualizations of the cardiac muscle, enabling them to diagnose and monitor conditions such as cardiac diseases, abnormalities, and functional disorders. An echocardiogram plays a crucial role in the early detection and diagnosis of various cardiac issues such as hypertension, myocardial infarction, valvular cardiac disease, and myocardial hypertrophy. It significantly contributes to determining treatment and management strategies. To achieve accurate disease diagnosis and develop appropriate treatment plans through echocardiography, it is essential to have a thorough understanding of proper probe usage, the precise acquisition of echocardiographic images, and the ability to interpret various echocardiographic examinations such as two-dimensional, M-mode, Doppler, etc. To enhance the skills required for echocardiography, medical educational institutions conduct theoretical classes, practical sessions using patient models, and clinical practice sessions with actual patients. However, issues such as inadequate practical adaptation due to theory-centric education, limitations in practical opportunities due to insufficient practice equipment, ethical or safety concerns arising during clinical practice, and a lack of educators leading to insufficient feedback, are currently being encountered. Hence, there is a need for new educational methods that can address the existing challenges in echocardiography education. In this paper, as part of these efforts, we propose a virtual reality-based immersive simulator for practical echocardiography training. The proposed echocardiography simulator allows users to explore a virtual echocardiography examination space by wearing a head-mounted display (HMD). This simulator consists of 3D virtual space models, interactive models manipulated by interaction devices, and 3D patient models containing normal or abnormal anatomical cardiac models. Using interactive devices such as HMD controllers and haptic devices, users can manipulate 3D models related to echocardiography within the simulator and interact with 3D patient models containing normal or abnormal anatomical cardiac models, allowing for the practice of echocardiography examinations. Ultimately, a performance evaluation of the developed immersive virtual reality simulator and usability validation targeting medical university students were conducted. The evaluation and validation results confirmed the potential efficacy of the proposed echocardiography VR simulator.

Numerous adolescents diagnosed with adolescent idiopathic scoliosis (AIS) often manifest symptoms indicative of functional gastrointestinal disorders (FGIDs). However, the precise connection between FGIDs and AIS remains unclear. The study involved adolescents drawn from sample datasets provided by the Korean Health Insurance Review and Assessment Service spanning from 2012 to 2016, with a median dataset size of 1,446,632 patients. The AIS group consisted of individuals aged 10 to 19 with diagnostic codes for AIS, while the control group consisted of those without AIS diagnostic codes. The median prevalence of FGIDs in adolescents with AIS from 2012 to 2016 was 24%. When accounting for confounding factors, the analysis revealed that adolescents with AIS were consistently more prone to experiencing FGIDs each year (2012: adjusted odds ratio (aOR), 1.21 [95% confidence interval (CI), 1.10–1.35], p < 0.001; 2013: aOR, 1.31 [95% CI, 1.18–1.46], p < 0.001; 2014: aOR, 1.24 [95% CI, 1.12–1.38], p < 0.001; 2015: aOR, 1.34 [95% CI, 1.21–1.49], p < 0.001; and 2016: aOR, 1.35 [95% CI, 1.21–1.50], p < 0.001). These findings suggest that AIS is correlated with an elevated likelihood of FGIDs, indicating that AIS may function as a potential risk factor for these gastrointestinal issues. Consequently, it is recommended to provide counseling to adolescents with AIS, alerting them to the heightened probability of experiencing chronic gastrointestinal symptoms.

Objectives This study aimed to determine the association between metabolic syndrome (MetS) and the incidence of colorectal cancer (CRC) in Korean women with obesity. Methods Cancer-free women (n=6 142 486) aged 40–79 years, who underwent National Health Insurance Service health examinations in 2009 and 2010 were included. The incidence of CRC was followed until 2018. The hazard ratio (HR) of MetS for the incidence of colon and rectal cancer was analyzed according to body mass index (BMI) categories, adjusting for confounders such as women’s reproductive factors. In addition, the heterogeneity of associations across BMI categories was assessed. Results Women with MetS were at increased risk of colon and rectal cancer compared to women without MetS (HR, 1.20; 95% confidence interval [CI], 1.16 to 1.23 and HR,1.15; 95% CI, 1.11 to 1.20), respectively. The HR of MetS for colon cancer across BMI categories was 1.12 (95% CI, 1.06 to 1.19), 1.14 (95% CI, 1.08 to 1.20), and 1.16 (95% CI, 1.12 to 1.21) in women with BMIs