Among various active cell balancing circuits, a switched capacitor circuit is promising because it can be implemented with low cost and small size. However, when the switched capacitor is applied in ...the lithium-ion battery, cell balancing speed is generally slow when the number of batteries is high. Therefore, this paper proposes the chain structure of the switched capacitor to increase balancing speed, particularly among outer cells. In this paper, the cell balancing principle of the conventional switched capacitor is explained, and the reason why slow cell balancing of the switched capacitor is shown in the lithium-ion battery is analyzed. To improve cell balancing speed, two circuits with chain structure are proposed. The balancing performance of the proposed circuits is confirmed by computer simulation, and a comparison between conventional and proposed circuits is presented. The theoretical analysis on the cell balancing speed of conventional structures and the proposed chain structure is also shown in this paper. Experimental tests were carried out to verify the validity of the proposed structures, and the experimental results show an improved balancing performance of the proposed circuit.
In the lithium-ion battery systems for electric vehicles (EVs), a battery management system (BMS) is essential for enhancing the battery's life cycle and safety. As a result, a BMS is required to ...realize both the effective cell monitoring and balancing. Moreover, individual cell balancing and monitoring circuit with a smaller size are required in a large number of battery cells. To meet these requirements, a modularized charge equalizer using the monitoring integrated circuit (IC) is proposed for EV battery strings. The proposed scheme exhibits efficient charge equalization with simple control of the monitoring IC. In the proposed equalizer, the battery string is modularized into a master module and multiple slave modules. A central equalization converter in the master module is shared by all of the battery cells through the module and cell switches in the slave module, instead of a dedicated charge equalizer for each of the cells. Individual charge equalization can be controlled by the cell monitoring IC in the slave module. With this configuration, the battery monitoring and balancing can be effectively merged into one controller. Moreover, the individual charge equalizer can be effectively implemented without affecting the size or cost based on the numbers of cells. In this paper, a prototype for 88 lithium-ion battery cells is optimally designed and implemented. Experimental results verify that the proposed method exhibits outstanding balancing performance with simple operation methods.
This work reports a new class of liquid crystal elastomers (LCEs) cross‐linked with poly(ether‐thiourea) comprising a triethylene glycol spacer (LCE‐TUEG) wherein thiourea bonds impart a hydrogen ...bonding capability as well as permit dynamic covalent bond (DCB) exchange at elevated temperatures. While hydrogen bonding enhances the mechanical properties of LCE‐TUEG, the DCB allows the macromolecular network rearrangement of the LCEs, resulting in various useful properties that are not present in conventional LCEs, including the ability to undergo welding, melt and solution reprocessing, reprogrammable actuation, and self‐healing. By exploiting these dynamic features, electrically powered artificial muscles are fabricated that can be actuated by Joule heating using a resistive wire. In particular, an excellent specific work is demonstrated (≈65 J kg−1) for the artificial muscle, and full recyclability of both the LCE matrix and the metallic heating wire is achieved. Furthermore, a biomimetic artificial hand is created by welding and assembling multiple LCE‐TUEG films embedded with heating wires, followed by mechanical alignment. The integration of a microcontroller to the artificial hand enables the selective actuation of each finger, and various hand gestures are successfully demonstrated.
A new class of exchangeable liquid crystal elastomers (LCEs) incorporating thiourea bonds is developed, which offers various useful properties such as welding, melt‐ and solution reprocessing, reprogrammable actuation, and self‐healing. Based on the dynamic features of LCEs, an electrically powered artificial muscle and an artificial hand are fabricated, which can undergo selective actuation by integrating a microcontroller through Joule heating.
Bkv-miR-B1-5p, one of the microRNAs encoded by BK virus, was recently reported to be elevated in the blood among the patients with BK virus nephropathy (BKVN). Urinary exosome was suggested to be a ...possible source of biomarker for kidney diseases, but it was unknown whether it could contain viral microRNA as well as human microRNAs. The aim of this study was to evaluate whether urinary exosomal BK viral microRNA were expressed during replication and could be used to diagnose BKVN in kidney transplant recipients.
In a cross-sectional multicenter study, we collected and analyzed 458 graft biopsies from 385 kidney transplant recipients. Urine samples were collected at the time of graft biopsy, and microRNAs in urinary exosome were measured once. For 13 patients with BKVN and 67 age, sex-matched kidney transplant recipients, we measured BK viral microRNA B1-5p, 3p and human microRNA-16 in urinary exosomal fraction and compared the diagnostic value with BK viral load in plasma and urine.
Pathology proven BKVN was diagnosed in 13 patients (2.8%). High levels of bkv-miR-B1-5p and bkv-miR-B1-3p were shown in all patients with BKVN. Meanwhile, plasma BK viral load assay (cut-off value of ≥ 4.0 log10 copies/mL) showed false negative in 3 cases and urinary BK viral load assay (cut-off value of ≥ 7.0 log10 copies/mL) showed false negative in 1 case among these 13 patients. The receiver operator characteristics curve analysis for bkv-miR-B1-5p and bkv-miR-B1-5p/miR-16 showed excellent discriminative power for the diagnosis of BKVN, with area under the curve values of 0.989 and 0.985, respectively.
This study suggests that urinary exosomal bkv-miR-B1-5p and bkv-miR-B1-5p/miR-16 could be surrogate markers for the diagnosis of BKVN.
The nuclear factor-erythroid 2 p45-related factor 2 (NRF2, also called
) and its cytoplasmic repressor, Kelch-like ECH-associated protein 1 (KEAP1), are major regulators of redox homeostasis ...controlling a multiple of genes for detoxification and cytoprotective enzymes. The NRF2/KEAP1 pathway is a fundamental signaling cascade responsible for the resistance of metabolic, oxidative stress, inflammation, and anticancer effects. Interestingly, a recent accumulation of evidence has indicated that NRF2 exhibits an aberrant activation in cancer. Evidence has shown that the NRF2/KEAP1 signaling pathway is associated with the proliferation of cancer cells and tumerigenesis through metabolic reprogramming. In this review, we provide an overview of the regulatory molecular mechanism of the NRF2/KEAP1 pathway against metabolic reprogramming in cancer, suggesting that the regulation of NRF2/KEAP1 axis might approach as a novel therapeutic strategy for cancers.
Nonalcoholic steatohepatitis (NASH) is considered as a progressive form of nonalcoholic fatty liver disease (NAFLD). To distinguish NASH from nonalcoholic fatty liver (NAFL), we evaluated the ...diagnostic value of circulating miRNAs. Small RNA sequencing was performed on 12 NAFL patients and 12 NASH patients, and the miRNA expression was compared. After selecting miRNAs for the diagnosis of NASH, we analyzed the diagnostic accuracy of each miRNA and the combination of miRNAs. External validation was performed using quantitative reverse transcription PCR. Among the 2,588 miRNAs, 26 miRNAs significantly increased in the NASH group than in the NAFL group. Among the 26 elevated miRNAs in the NASH group, 8 miRNAs were selected, and in silico analysis was performed. Only four miRNAs (miR-21-5p, miR-151a-3p, miR-192-5p, and miR-4449) showed significant area under the receiver operating characteristic curve (AUC) values for NASH diagnosis. The combination of the four miRNAs showed satisfactory diagnostic accuracy for NASH (AUC 0.875; 95% CI 0.676-0.973). External validation revealed similar diagnostic accuracy for NASH (AUC 0.874; 95% CI 0.724-0.960). NASH represents significantly distinct miRNA expression profile compared with NAFL. The combination of serum circulating miRNAs can be used as a novel biomarker for the NASH diagnosis in NAFLD.
In lithium-ion battery system for hybrid electric vehicle, charge equalizer is essential to enhance the battery life cycle and safety. However, for a large number of battery cells, a conventional ...equalizer has the difficulty of individual cell balancing and the implementation size problem as well as the cost. Moreover, it shows high voltage stress of electrical elements in the equalization converter due to the high voltage of battery pack. To improve these drawbacks, this paper proposes a modularized two-stage charge equalizer with cell selection switches. The proposed circuit employs the two-stage dc-dc converter to reduce the voltage stress of equalization converter. Contrary to conventional method, the proposed equalizer can achieve the individual cell balancing only through the cell selection switches. With the two-stage converter and the cell selection switches, the proposed equalizer leads to the great size reduction with lower cost which brings advancement of individual cell balancing in a large number of battery cells. In this paper, a prototype for 88 lithium-ion battery cells is optimally designed and implemented. Experimental results are presented to verify that the proposed equalization method has a good cell balancing performance showing the low voltage stress and small size with the lower cost.
Among the various cell balancing circuits for series-connected batteries, the bidirectional cell-to-cell balancing structure using two switches per cell shows good balancing ability. However, an ...increase in the number of switches leads to an increase in both cost and size. To reduce the number of switches, this paper proposes a new cell-to-cell balancing circuit with a center-cell concentration structure. The proposed circuit collects the charges of an overcharged cell into the center cell, and then the collected charges are redistributed to the other cells. The proposed circuit has a unidirectional balancing structure with single switch per cell. However, it can achieve competitive balancing ability when compared with the bidirectional structure. In this paper, the operational principles of the proposed circuit are analyzed, and a comparison between the conventional and proposed circuits is shown. To verify the validity of the proposed circuit, experiments with 15.5-Ah batteries are carried out, and the experimental results demonstrate the improved cell balancing ability although a single switch is used per cell.
Sarcopenia is a common syndrome in chronic diseases such as liver cirrhosis. The association between sarcopenia and outcomes, such as complications and survival has recently been described in various ...patient groups. However, study results remain inconclusive. Therefore, the aim of this study was to systematically review the impact of sarcopenia on outcome in patients with cirrhosis.
We conducted a systematic review (SR) and meta-analysis (MA) on the impact of sarcopenia on outcome in liver cirrhosis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Of the 312 studies identified, 20 were eligible according to our inclusion criteria. Most of the studies used CT to diagnose sarcopenia. Two studies used bioelectrical impedance analysis (BIA), 10 studies used skeletal muscle index (SMI) and 8 studies used total psoas muscle area (TPA). Seven studies included Asian participants and the remaining 13 studies included Western participants. The prevalence rate of sarcopenia among participants was mean 48.1%, and appeared more among men with a rate of 61.6% whereas the rate was 36% for women. With respect to clinical outcomes, patients with sarcopenia had poorer survival rates and an increased risk of complications such as infection compared to those without sarcopenia. According to the analysis of race subgroup, Asians had a HR 2.45 (95% confidence interval (CI) = 1.44-4.16, P = 0.001) of mortality whereas Westerners had a HR 1.45 (95% CI = 1.002-2.09, P<0.05).
Based on this SR and MA, the presence of sarcopenia is related to a poor prognosis and occurrence of cirrhotic complications and could be used for risk assessment. Moreover, Asian participants had higher mortality related to sarcopenia compared to the Western participants.
Highlights • We evaluate the PD-1/PD-Ls pathway molecules in pulmonary pleomorphic carcinoma (PC). • PD-L1 and PD-L2 are highly expressed in pulmonary PCs. • PD-L1 expression is higher in sarcomatous ...areas than carcinomatous portion in PCs. • PD-L1-positive PCs were infiltrated by higher numbers of CD8+ lymphocytes. • Targeting the PD-1/PD-Ls pathway may be potential therapeutic strategy for pulmonary PC.
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