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According to the green growth and carbon-neutral policy in Korea, the installation of large-capacity ESSs is rapidly being increased, but a total number of 50 ESS fire cases have occurred since the end of 2023. ESSs are typically composed of series-parallel connections with numerous Li-ion batteries, and when the temperature of a deteriorated cell increases due to thermal, electrical, and mechanical stress, thermal runaway can occur due to additional heat generated by an internal chemical reaction. Here, an internal chemical reaction in a Li-ion battery results in the different characteristics on the decomposition reaction and heat release depending on the operation conditions in the ESS, such as the rising temperature rate, convective heat transfer coefficient, and C-rate of charging and discharging. Therefore, this paper presents mathematical equations and modeling of thermal runaway, composed of the heating device section, heat release section by chemical reaction, chemical reaction section at the SEI layer, chemical reaction section between the negative and positive electrodes and solvents, and chemical reaction section at the electrolyte by itself, based on MATLAB/SIMULINK (2022), which were validated by a thermal runaway test device. From the simulation and test results based on the proposed simulation modeling and test device according to the operation conditions in ESSs, it was found that the proposed modeling is an effective and reliable tool to evaluate the processing characteristics of thermal runaway because the occurrence time intervals and maximum temperatures had almost the same values in both the test device and simulation modeling. Accordingly, it was confirmed that the rising temperature rate and the convective heat transfer coefficient were more critical in the thermal runaway than the C-rate of charging and discharging.

In general, severe load imbalances in small AC micro-grid systems can degrade their operational performance and their maintenance. This is because the unbalanced load in the micro-grid affects the energy flow and the voltage regulation functions of each phase. In order to solve the voltage imbalance problem, several algorithms for the 3-phase 4-leg CVCF inverter have been proposed, but the control algorithms are not enough to operate the 4-leg CVCF inverter in a stable manner. Therefore, this paper proposes a single-phase voltage and power control algorithm for the 3-phase 4-leg CVCF inverter based on a dq control in order to improve the voltage imbalance problem caused by a severely unbalanced load, where the single phase voltage control algorithm is composed of an αβ-dq and a dq-αβ transformer, a voltage and a current controller, and an off-set controller and a PWM, and the single-phase power control algorithm is also composed of an αβ-dq and a dq-αβ transformer, an active/reactive power and a current controller, and an off-set controller and a PWM. Additionally, this paper performs modeling of the single-phase voltage and the power controller for a 4-leg CVCF inverter using the Matlab/Simulink S/W. From the simulation results, it is confirmed that the transient stability of the proposed single voltage control algorithm can be improved compared to the conventional control algorithm, and voltage control can also be maintained in a stable manner under extremely unbalanced conditions. Further, it is confirmed that 3-phase currents of the proposed single-phase power control algorithm are controlled in a stable manner under extremely unbalanced conditions.

Generally, PV (photovoltaic) modules are known as devices which are used semi-permanently for more than 20 years, but the electrical performance and lifespan of PV modules can be significantly degraded due to various environmental factors. Thus, a proper evaluation method for aging phenomenon of PV modules is required. Although there already are methods which compare adjusted PV output power based on STC (standard test condition) with initial PV module specification, or perform direct comparison by conducting the test under STC, there are issues with objectivity or efficiency in the existing evaluation method of aging phenomenon due to the data distortion while adjusting measured data or difficulties in implementation. Therefore, in order to overcome the above-mentioned disadvantage of the existing evaluation method for deterioration in PV modules and evaluate the aging characteristics of PV modules based on on-site measurement data in an accurate and efficient manner, this paper implements a test device for aging diagnosis to measure and collect actual data from a PV module section, and presents a modeling of data analysis for aging phenomenon with MATLAB S/W in order to minimize the variability of PV output, communication error, delay, etc. Furthermore, this paper confirms the usefulness of the presented test device for aging diagnosis of the PV modules which is accurately evaluated by considering on-site measurement of PV output power by season.

Measuring displacement is essential for assessing the safety of bridges. Non-contact sensors such as vision sensors can precisely measure displacement but may be expensive or incapable of micro-scale measurement at a low cost, unlike contact displacement sensors, which are economical but challenging to install. This study proposes an economical, remote non-contact sensor system. The system comprises a laser beam transmitter and a light receiver, deriving the displacement based on the position where the laser beam is irradiated to the light-receiving surface. To measure this, the light receiver was installed at the measurement point and included a wireless communicator to transmit the displacement data. A displacement experiment was conducted to evaluate the performance. The results confirmed that precise displacement measurements were possible at a resolution of 100 µm. For bridge load tests, a light receiver under a bridge was installed, laser beams irradiated to the light-receiving surface from a distance, and the displacement was measured for each test and compared with the values measured by a conventional contact sensor. The results were highly consistent with those of the existing sensor, indicating that the proposed sensor system applies to bridge loading tests and the safety diagnosis for various structures.

Brachiocephalic artery aneurysm is uncommon but may require surgery because it tends to enlarge, rupture, or cause symptoms related to thrombosis or compression. This case report describes a brachiocephalic artery aneurysm in a 72-year-old man who presented at the hospital with dyspnea and hemoptysis resulting from impending rupture and tracheal communication.

Percutaneous transluminal angioplasty is a well-known treatment for arteriovenous fistula stenosis. Balloon rupture during endovascular procedures is a rare but possible complication. The bursting balloon itself does not cause a serious problem, but it can occasionally cause entrapment, especially in case of breakdown of the balloon catheter tip. Here, we present four cases of balloon rupture during angioplasty in the hemodialysis circuit. In three cases, the ruptured balloon catheter was removed by cutdown of access conduit, while in one case, tip of ruptured balloon catheter was migrated into the pulmonary artery and was removed surgically. The operator must attempt to reduce the risk of balloon rupture by gradually expanding the balloons under bursting pressure. If the balloon bursts, it should not be removed excessively and attempt should be made to remove it using endovascular techniques. Surgical removal is considered after careful evaluation of the condition of the balloon and vessel.

We describe aortic arch endarterectomy performed concomitantly with on-pump cardiac surgery in 2 patients with grade V arch atherosclerosis. In both patients, transesophageal echocardiographic findings led to the diagnosis of severe arch atherosclerosis associated with a mobile atheromatous plaque in the aortic arch. The severe arch atherosclerosis was managed with endarterectomy under deep hypothermic circulatory arrest. In patients with severe grade V atherosclerosis in the aortic arch, performing endarterectomy simultaneously with primary cardiac surgery may be justified as a way to reduce the risk of peripheral embolism, including cerebrovascular accidents, with minimal additional surgical risk.

Abstract Background Open distal graft to proximal aortic arch anastomosis is central to a hemiarch replacement. Even if the ischemic tolerance time of several organs during circulatory arrest (CA) at normothermia is much longer than that of the brain, very little is known about the safety and clinical efficacy of moderate hypothermia for organ protection during the average duration of CA needed for aortic arch replacement. Hemiarch replacement using the standard techniques of deep hypothermia and antegrade perfusion has often ignored the effects of prolonged distal body CA. Maintenance of distal organ, especially the liver and kidney, perfusion reduces the risk of postoperative renal dysfunction and coagulopathy. Case presentation A 72-year-old female patient was referred to our institute due to chest discomfort. Radiologic investigations revealed a giant aneurysm of the ascending aorta extending but confined to the proximal aortic arch. We performed an alternative technique for hemiarch replacement using a dual inflow source. Conclusions Although this technique cannot apply to all aneurysmal aortic diseases, our basic technique involving the use of dual inflow may be well suited for standard hemiarch replacement that is confined to the proximal aortic arch, given the shortening of the bypass and ischemic times.

A solitary fibrous tumor (SFT) is a mesenchymal fibroblastic tumor inside the pleura, for which complete surgical resection is the standard treatment. For large SFTs, preoperative identification of tumor-feeding vessels using angiography is important for achieving complete resection without unexpected operative bleeding. Extensive adhesions can make resection difficult in a limited operative window, and pulmonary resection may be required to achieve complete SFT resection. Herein, we report successful resection of a large pleural SFT in a 39-year-old man without any complications using a 2-stage approach, in which ligation of the feeding vessels through small another operative window was the first step.

Abstract Background An aberrant right subclavian artery (ARSA) is a relatively prevalent vascular anomaly. What is the most appropriate treatment for thoracic aortic aneurysm combined a non-aneurysmal change ARSA? Case presentation A 52-year-old man was admitted to our institute due to a history of chronic cough, dysphagia and an abnormal chest radiographic finding. Because of his progressive symptoms and large fusiform thoracic aneurysm, we performed the hybrid repair for simultaneous relief of an ARSA causing dysphagia and thoracic aneurysm. Conclusion In case without aneurysm of ARSA, especially in conjunction with approximate thoracic aneurysm, our approach is suitable because the revascularization using the right carotid to subclavian artery re-routing prior to endograft deployment is justified in order to preserve circulation of posterior brain, spinal cord, internal mammary artery and upper limb and to prevent large retrograde type II endoleaks, as well as simplicity and durability.

Parkinson’s disease (PD) is a chronic progressive neurodegenerative movement disorder characterized by the selective loss of dopaminergic neurons within the substantia nigra (SN). While the precise etiology of dopaminergic neuronal demise is elusive, multiple lines of evidence indicate that neuroinflammation is involved in the pathogenesis of PD. We have previously demonstrated that subcutaneous administration of bee venom (BV) phospholipase A2 (bvPLA2) suppresses dopaminergic neuronal cell death in a PD mouse model. In the present study, we established standardized methods for producing bvPLA2 agent isolated from crude BV at good manufacturing practice (GMP) facility. The therapeutic efficacy of purified bvPLA2 agent was examined in MPTP-induced PD mice. Importantly, administration of purified bvPLA2 in a dose-dependent manner reversed motor deficits in PD mice as well as inhibited loss of dopaminergic neurons within the SN of PD mice. The concentration-dependent action of standardized bvPLA2 appeared to be related to the induction of CD4+CD25+Foxp3+ regulatory T cells (Tregs), which, in part, inhibits T helper 1 (Th1) and Th17 polarization and suppresses microglial activation in PD mice. Taken together, these results suggest that standardized bvPLA2 purified from BV shows a neuroprotective effect against PD and thus has a potential target for treatment of PD.

[This corrects the article DOI: 10.1371/journal.pbio.2001951.].

Bee venom contains a number of pharmacologically active components, including enzymes and polypeptides such as phospholipase A2 (PLA2) and melittin, which have been shown to exhibit therapeutic benefits, mainly via attenuation of inflammation, neurotoxicity, and nociception. The individual components of bee venom may manifest distinct biological actions and therapeutic potential. In this study, the potential mechanisms of action of PLA2 and melittin, among different compounds purified from honey bee venom, were evaluated against Parkinson’s disease (PD). Notably, bee venom PLA2 (bvPLA2), but not melittin, exhibited neuroprotective activity against PD in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. MPTP-induced behavioral deficits were also abolished after bvPLA2 treatment, depending on the PLA2 content. Further, bvPLA2 administration activated regulatory T cells (Tregs) while inhibiting inflammatory T helper (Th) 1 and Th17 cells in the MPTP mouse model of PD. These results indicate that bvPLA2, but not melittin, protected against MPTP and alleviated inflammation in PD. Thus, bvPLA2 is a promising and effective therapeutic agent in Parkinson’s disease.

Fasting reduces glucose levels and protects mice against chemotoxicity, yet drugs that promote hyperglycemia are widely used in cancer treatment. Here, we show that dexamethasone (Dexa) and rapamycin (Rapa), commonly administered to cancer patients, elevate glucose and sensitize cardiomyocytes and mice to the cancer drug doxorubicin (DXR). Such toxicity can be reversed by reducing circulating glucose levels by fasting or insulin. Furthermore, glucose injections alone reversed the fasting-dependent protection against DXR in mice, indicating that elevated glucose mediates, at least in part, the sensitizing effects of rapamycin and dexamethasone. In yeast, glucose activates protein kinase A (PKA) to accelerate aging by inhibiting transcription factors Msn2/4. Here, we show that fasting or glucose restriction (GR) regulate PKA and AMP-activated protein kinase (AMPK) to protect against DXR in part by activating the mammalian Msn2/4 ortholog early growth response protein 1 (EGR1). Increased expression of the EGR1-regulated cardioprotective peptides atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in heart tissue may also contribute to DXR resistance. Our findings suggest the existence of a glucose-PKA pathway that inactivates conserved zinc finger stress-resistance transcription factors to sensitize cells to toxins conserved from yeast to mammals. Our findings also describe a toxic role for drugs widely used in cancer treatment that promote hyperglycemia and identify dietary interventions that reverse these effects.