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This study improves the mechanical strength and long-term durability of Ni-8YSZ, a commonly used anode support(AS) for Solid Oxide Fuel Cells (SOFC). Instead of Ni-8YSZ, Ni-3YSZ is due to its high mechanical strength and low cost. 3YSZ alone had the disadvantage of degradation of mechanical strength in high-temperature, humidified hydrogen atmospheres due to phase transformation. The addition of nano-ZrO2 and nano-WO3 was expected to improve mechanical strength and long-term durability due to the Hall-Petch equation. For uniform dispersion, NiO and 3YSZ powders were ball-milled for 100 hours, and nano-ZrO2 or nano-WO3 was also added. The powders were sintered at 1400 oC for 5 hours. Sintered specimens were reduced at 750 oC in a hydrogen atmosphere for 8 hours. The reduced specimens were reduced for 500 and 1000 hours, respectively, at 900 oC in a humidified hydrogen atmosphere, which is an accelerated atmosphere. Ni-3YSZ with nano-ZrO2 added had greatly improved mechanical strength and long-term durability.

Variable renewable energy sources (solar, wind, etc.) are difficult to maintain efficient hierarchical operation and stable power quality from the perspective of the power system. In preparation for this increase in the proportion of renewable energy, it is necessary to prepare counterplan for power system intelligence and flexibility, such as power backup systems, power storage devices, smart control, and demand response. It is expected that control the volatility of renewable energy and supply-demand balance can be solved by producing/storing hydrogen using idle power and generating electricity using fuel cells. High-efficiency SOFC technology that can manage with daily cycle load fluctuations is the best alternative. In this work, the goal is to develop basic technologies for energy network systems that can respond to daily cycle power fluctuations of renewable energy and increase system stability through SOFC cell/stack design and durability enhancement. In this study, in order to secure the ability to cope with the variability of the power system, it is intended to present durability evaluation criteria for simultaneous heat and load cycles. Stack evaluation was performed in the current range of 0.25 ~ 0.50 A/cm2 in the case of the load cycle test and 500 ~ 700 °C in the case of the temperature cycle test.

We propose an active weighting algorithm for composite adaptive control to reduce the state and estimate errors while maintaining the estimation quality. Unlike previous studies that construct the composite term by simply stacking, removing, and pausing observed data, the proposed method efficiently utilizes the data by providing a theoretical set of weights for observations that can actively manipulate the composite term to have desired characteristics. As an example, a convex optimization formulation is provided, which maximizes the minimum eigenvalue while keeping other constraints, and an illustrative numerical simulation is also presented.

Endolysins produced by bacteriophages play essential roles in the release of phage progeny by degrading the peptidoglycan layers of the bacterial cell wall. Bacteriophage-encoded endolysins have emerged as a new class of antibacterial agents to combat surging antibiotic resistance. The crystal structure of mtEC340M, an engineered endolysin EC340 from the PBEC131 phage that infects Escherichia coli, was determined. The crystal structure of mtEC340M at 2.4 Å resolution consists of eight α-helices and two loops. The three active residues of mtEC340M were predicted by structural comparison with peptidoglycan-degrading lysozyme.

Study Design: This study was a retrospective case series.Purpose: This study was designed to determine whether direct vertebral rotation (DVR) of the lowest instrumented vertebra (LIV) using a high-density (HD) construct can reduce fusion segments without increasing adverse outcomes in selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS).Overview of Literature: LIV DVR is used to maximize spontaneous lumbar curve correction and reduce adverse outcomes during STF for AIS. However, evidence is limited on whether LIV DVR can allow a proximally located LIV and reduce fusion segments without increasing adverse outcomes.Methods: We reviewed consecutive patients with Lenke 1 AIS who underwent STF from 2000 to 2017. The patients were divided into two groups based on the surgical strategy used: low-density (LD) construct without DVR of the LIV (LD group) versus HD construct with DVR of the LIV (HD group). We collected data on the patient’s demographic characteristics, skeletal maturity, operative data, and measured radiological parameters in the preoperative and final follow-up radiographs. The occurrence of adding-on (AO) and coronal decompensation was also determined.Results: In this study, 72 patients (five males and 67 females) with a mean age of 14.1±2.3 years were included. No significant differences in the demographics, skeletal maturity, and Lenke type distribution were observed between the two groups; however, the follow-up duration was significantly longer in the LD group (64.3±25.7 months vs. 40.7±22.2 months, p

Background: Hemorrhagic Moyamoya disease (MMD) is a common subtype of MMD in adult patients, especially in East Asian countries. To our knowledge, current studies regarding factors affecting the prognosis in patients with hemorrhagic MMD is lacking. This study aimed to determine the potential prognostic factors for hemorrhagic MMD.Methods: This retrospective study reviewed patients with hemorrhagic MMD diagnosed at our hospital between June 2011 and June 2021. Patient outcome was measured at discharge using the extended Glasgow outcome scale (GOSE). Prognostic factors were assessed by multivariate logistic regression analysis.Results: Patients discharged with worst outcomes (GOSE 1 and 2) had significantly lower initial Glasgow coma scale (GCS) scores (5.9 ± 3.1 vs. 10.3 ± 3.7; P = 0.002) and were associated with more severe intraventricular hemorrhage (IVH) (P = 0.007), and IVH-related hydrocephalus requiring extraventricular drain (EVD) insertion was more common (n = 12 vs. n = 7; P = 0.001). The multivariate analysis showed that IVH-related hydrocephalus requiring EVD placement (OR 8.256, 95% CI 0.996–68.450; P = 0.016) and low initial GCS scores (OR 0.644; 95% CI 0.465–0.892; P = 0.008) were independent risk factors for unfavorable outcomes (GOSE 1–4) in patients with hemorrhagic MMD.Conclusion: This study analyzed several potential prognostic factors for patients with hemorrhagic MMD. Low initial GCS scores and IVH-related hydrocephalus requiring EVD insertion were related to unfavorable outcomes.

Herein for the first time, lignocellulose nanofibrils (LCNF) were prepared from pine-wood powder using microwave (MW)-assisted deep eutectic solvent (DES) pretreatment coupled with high-pressure homogenization. A DES based on choline chloride and lactic acid was employed, and LCNFs prepared by conventional DES pretreatment at 110°C (LCNF-110) and 130°C (LCNF-130) were used for comparison. Although MW treatment offered a high removal of lignin (70%) and hemicellulose (90%) within a short time (110 s), the morphological observations by scanning and transmission electron microscopies revealed excellent defibrillation of the conventionally heat-treated samples. Likewise, LCNF-110 and LCNF-130 exhibited high tensile strengths of 154.6 ± 5.0 and 136.8 ± 1.2 MPa, respectively, whereas that of LCNF-MW was only 75.6 ± 1.4 MPa. Interestingly, LCNF-MW with a lignin content between that of LCNF-110 and LCNF-130 exhibited high thermal stability (Tmax 309.6°C) and potent antioxidant properties. However, the lignin contents of the LCNFs determined their UV-radiation blocking efficiency, where LCNF-110 > LCNF-MW > LCNF-130. Furthermore, all LCNF films exhibited good visible-light transparency, flexibility, and water contact angles (> 87°), indicating their promising potential for packaging applications.

Background: The present study evaluated the association between participation in a rehabilitation program during a hospital stay and 1-year survival of patients requiring at least 21 days of mechanical ventilation (prolonged mechanical ventilation [PMV]) with various respiratory diseases as their main diagnoses that led to mechanical ventilation.Methods: Retrospective data of 105 patients (71.4% male, mean age 70.1±11.3 years) who received PMV in the past 5 years were analyzed. Rehabilitation included physiotherapy, physical rehabilitation, and dysphagia treatment program that was individually provided by physiatrists.Results: The main diagnosis leading to mechanical ventilation was pneumonia (n=101, 96.2%) and the 1-year survival rate was 33.3% (n=35). One-year survivors had lower Acute Physiology and Chronic Health Evaluation (APACHE) II score (20.2±5.8 vs. 24.2±7.5, p=0.006) and Sequential Organ Failure Assessment score (6.7±5.6 vs. 8.5±2.7, p=0.001) on the day of intubation than non-survivors. More survivors participated in a rehabilitation program during their hospital stays (88.6% vs. 57.1%, p=0.001). The rehabilitation program was an independent factor for 1-year survival based on the Cox proportional hazard model (hazard ratio, 3.513; 95% confidence interval, 1.785 to 6.930; p

Background: Coronavirus disease 2019 (COVID-19) is an ongoing global public health threat and different variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been identified. This study aimed to analyse the factors associated with negative conversion of polymerase chain reaction (PCR) and prognosis in critically ill patients according to the SARS-CoV-2 variant.Methods: This study retrospectively analysed 259 critically ill patients with COVID-19 who were admitted to the intensive care unit of a tertiary medical center between January 2020 and May 2022. The Charlson comorbidity index (CCI) was used to evaluate comorbidity, and a negative PCR test result within 2 weeks was used to define negative PCR conversion. The cases were divided into the following three variant groups, according to the documented variant of SARS-CoV-2 at the time of diagnosis: non-Delta (January 20, 2020–July 6, 2021), Delta (July 7, 2021– January 1, 2022), and Omicron (January 30, 2022–April 24, 2022).Results: The mean age of the 259 patients was 67.1 years and 93 (35.9%) patients were female. Fifty (19.3%) patients were smokers, and 50 (19.3%) patients were vaccinated. The CCI (hazard ratio [HR], 1.555; p

Purpose: As resuscitative endovascular balloon occlusion of the aorta (REBOA) is performed in an extremely emergent situation, achieving competent clinical practice is mandatory. Although there are several educational courses that teach the REBOA procedure, there have been no reports evaluating the impact of training on clinical practice. Therefore, this study is aimed to evaluate the effects of the course on procedural performance during resuscitation and on clinical outcomes. Methods: Patients who were managed at a regional trauma center in Dankook University Hospital from August 2016 to February 2018 were included and were grouped as precourse (August 2016–August 2017, n=9) and postcourse (September 2017–February 2018, n=9). Variables regarding injury, parameters regarding REBOA procedure, morbidity, and mortality were prospectively collected and reviewed for comparison between the groups. Results: Demographics and REBOA variables did not differ between groups. The time required from arterial puncture to balloon inflation was significantly shortened from 9.0 to 5.0 minutes (P=0.003). There were no complications associated with REBOA after the course. Mortality did not show any statistical difference before and after the course. Conclusions: The endovascular training for REBOA pilot course, which uses a modified form of flipped learning, realistic simulation of ultrasound-guided catheter insertion and balloon manipulation, and competence assessment, significantly improved procedural performance during resuscitation of trauma patients.

The prevalence of aneurysm formation in adults with Moyamoya disease (MMD) is higher than that in the general population. The treatment strategy is often individualized based on the patient’s disease characteristics. A 22-year-old man was diagnosed with MMD after presenting a small thalamic intracerebral and subarachnoid hemorrhage in the quadrigeminal cistern. Cerebral angiography revealed a small aneurysm (2.42 mm) in the left anterior choroidal artery. Since the hemodynamics in the left hemisphere was compromised, an indirect bypass surgery was performed. The patient’s condition deteriorated postoperatively because of poor perfusion of the internal carotid artery, and massive hydration was required. During neurocritical care, the aneurysm increased in size (5.33 mm). An observation strategy was adopted because of the distal aneurysmal location and the high risk involved. Subsequently, the patient recovered, and newly developed collateral flow appeared from the external carotid artery. Additionally, a dramatic size reduction of the aneurysm (1.51 mm) was noticed. Our case suggests that MMD-related dissecting aneurysms on a distal cerebral artery, which present a high risk of embolization, could be managed by indirectly reducing the hemodynamic burden. Massive hydration in such cases should be avoided or balanced to avoid the risk of rapid growth and aneurysm rupture.

PURPOSE The purpose of this study is to analyze the biomechanical variables involved in ballet dancers’ ankle muscle imbalance when performing relevé movements.METHODS The subjects of this study (n=14, age: 22.29±1.73 years old, height: 161.4±5.06cm, weight: 51.88±7.51kg) were 14 ballet dancers with 9 years of experience. Based on the reciprocal muscle strength ratio, the dancers were divided into the following groups: Close to the normal value (RMIS) and far from the normal value (RMIB) using the maximum values o f plantar flexion and dorsiflexion of the ankle joint using an isokinetic measurement equipment (60°/sec). RMIB). The biomechanical variables, namely the ankle joint movement and ground reaction force, were subsequently measured. SPSS 26.0 was used for data analysis and independent t-test was used for statistical verification. RESULTS The ground reaction force in the Z (vertical) direction based on the ankle joint muscle strength imbalance of ballet dancers was significantly lower in the RMIB group. In addition, although it was not a statistically significant difference, the plantar flexion movement was lower in the RMIB group, and there was a significant difference in the generation of ankle joint movement in the Z direction.CONCLUSIONS In conclusion, in order for a ballet dancer to efficiently utilize the force generated from the supporting leg when performing a movement, ankle imbalance must be taken into consideration when training.

Purpose: Renal injury occurs in up to 5% of trauma cases and the kidney is the third most wounded abdominal organ. The study objective was to analyze clinical characteristics of patients with blunt renal trauma and review the treatment of high-grade blunt renal injuries.Methods: The medical charts of trauma patients who visited Haeundae Paik Hospital between March 2010 and February 2020 were retrospectively analyzed. Data on demographics, injury patterns, clinical presentation, management, and outcomes were analyzed.Results: A total of 68 patients with renal trauma were included in this study. The most common renal injury was Grade III (n = 27, 39.7%). Falling was the predominant mechanism of injury (n = 33, 48.5%), and 23.5% (n = 16) of patients sustained isolated renal trauma. Organ damage related to kidney injury included chest injury (57.4%, n = 39) and abdominal or pelvic content injury (48.5%, n = 33). The overall mortality rate was 2.9% (n = 2). There were 45 cases of high-grade renal trauma (AAST Kidney injury scale Grade Ш-V). There was no statistical difference in the outcomes of high-grade (n = 44, 97.8%) and low-grade (n = 23, 100%) renal trauma patients who received nonoperative treatment (p = 0.511). Variables did not differ significantly, except for the injury severity score which was statistically significantly different between low-grade and high-grade renal trauma patients (p = 0.001).Conclusion: Most patients with traumatic renal injury, even those with high-grade injury, can be managed by nonoperative treatment, and have a good prognosis.

Subarachnoid hemorrhage (SAH) due to ruptured posterior cerebral artery (PCA) intracranial arterial dolichoectasia (IADE) is very rare. As these lesions are difficult to treat microsurgically, neurointervention is preferred because the dolichoectatic artery does not have a clear neck, and the surgical field of view was deep seated with the SAH. However, in some cases, neurointervention is difficult due to anatomical variation of the blood vessel to access the lesion. In this case, a 30-year-old male patient presented with a ruptured PCA IADE and an aortic arch anomaly. Aortic arch anomalies render it difficult to reach the ruptured PCA IADE via endovascular treatment. The orifice of the vertebral artery (VA) was different from the usual cases, so it was difficult to find the entrance. After only finding the VA and arriving at the lesion along the VA, trapping was performed. Herein, we report the PCA IADE with aortic arch anomaly endovascular treatment methods and results.

The anatomical characteristics of the culms and culm bases of ssanggol- and min-bamboo, which are mutated species of Phyllostachys bambusoides, were investigated using optical microscopy to understand the material properties. The vascular bundles in the culms and culm bases of both species were type I. There were a few abnormal vascular bundles in the culm base of ssanggol-bamboo, and more developed fiber bundles in the inner part of min-bamboo. A wavy surface was observed in the pith cavity of the ssanggol-bamboo culms. In the inner part, the vascular bundles of min-bamboo culms showed a regular diagonal arrangement, whereas those of ssanggol-bamboo were distributed randomly. In the culm base, ssanggol-bamboo had a significantly higher proportion of parenchyma and vessels, whereas min-bamboo had a higher fiber proportion. Both species had comparable proportions of cells in their culms. The vascular bundle density of min-bamboo was significantly higher than that of ssanggol-bamboo, whereas ssanggol-bamboo showed a significantly larger vessel diameter than min-bamboo. Ssanggol-bamboo had a shorter parenchyma cell length and larger parenchyma cell width than min-bamboo, whereas the min-bamboo culm showed a longer fiber length than that of ssanggol-bamboo. Furthermore, in the culm base, the fibers of ssanggol-bamboo were longer.