This letter presents a high-power resonant inverter using an enhancement mode gallium nitride (eGaN) device with magnetic resonant coupling (MRC) coils at 13.56 MHz for wireless power transfer (WPT). ...The power inverter driving the transmitting coils is based on a class Φ 2 inverter, a single-switch topology with low switch-voltage stress, and fast transient response. The implementation utilizes a recently available eGaN device in a low-inductance package that is compatible with operation in the 10 s of MHz switching frequency. In this letter, we present experimental measurements of the inverter in a WPT application and characterize the system performance over various distances and operating conditions. Before using MRC coils, we evaluated the performance of the class Φ 2 inverter with the eGaN FET. It delivered 1.3-kW output to a 50-Ω load with an efficiency of 95% when a 280-V input voltage was applied. For WPT operation, we added the open-type four-coil unit with a diameter of 300 mm to deliver power over 270-mm distance. With the addition of MRC coils, the class Φ 2 inverter provided 823-W output power with 87% efficiency over 270-mm distance between coils.
The rising consumption of pharmaceuticals, personal care products, and endocrine disruptive compounds for healthcare purposes and improving living standards has resulted in the widespread occurrence ...of organic micropollutants (MPs) in water and wastewater. Conventional water/wastewater treatment plants are faced with inherent limitations in tackling these compounds, leading to difficulties in the provision of secure and safe water supplies. In this context, membrane technology has been found to be a promising method for resolving this emerging concern. To ensure the suitability of membrane-based treatment processes in full-scale applications, we first need to develop a better understanding of the behavior of MPs and the mechanisms behind their removal using advanced membrane technologies. This review provides a thorough overview of the advanced membrane-based treatment methods available for the effective removal of MPs, including reverse osmosis, nanofiltration, ultrafiltration, forward osmosis, and membrane distillation.
•Greater use of PhACs, PCPs, and EDCs are resulting in the widespread occurrence of MPs.•RO, NF, FO, and MD membranes showed promising results for MPs removal.•Characteristics of MPs and solution chemistry had a significant effect on their retention.•Removal of MPs improved when membranes were modified using nanomaterials and employed in optimized conditions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper presents an impedance compression network (ICN) design in a wireless power transfer (WPT) system to compensate for distance or alignment variations between coils. In midrange WPT ...applications, magnetic resonant coupling coils are mainly implemented to achieve high efficiency for charging batteries. However, a distance or horizontal alignment variation between coils changes their coupling coefficient, and it decreases the overall performance of WPT systems because the zero voltage switching in a resonant inverter is lost. In order to reduce coil impedance variation, we propose an ICN that compresses variations in coil impedance. The ICN consists of a resistance compression network and a phase compression network to suppress magnitude and phase variations, respectively, in the coil impedance. Only passive components, such as inductors and capacitors, are used to implement an ICN.
Nearly all biosensing platforms can be described using two fundamental steps-collection and detection. Target analytes must be delivered to a sensing element, which can then relay the transduced ...signal. For point-of-care technologies, where operation is to be kept simple, typically the collection step is passive diffusion driven-which can be slow or limiting under low concentrations. This work demonstrates an integration of both active collection and detection by using resonant wireless power transfer coupled to a nanogap capacitor. Nanoparticles suspended in deionized water are actively trapped using wireless dielectrophoresis and positioned within the most sensitive fringe field regions for wireless impedance-based detection. Trapping of 40 nm particles and larger is demonstrated using a 3.5 V
, 1 MHz radiofrequency signal delivered over a distance greater than 8 cm from the nanogap capacitor. Wireless trapping and release of 1 µm polystyrene beads is simultaneously detected in real-time over a distance of 2.5 cm from the nanogap capacitor. Herein, geometric scaling strategies coupled with optimal circuit design is presented to motivate combined collection and detection biosensing platforms amenable to wireless and/or smartphone operation.
Autophagy is a critical cytoprotective mechanism against stress, which is initiated by the protein kinase Unc-51-like kinase 1 (ULK1) complex. Autophagy plays a role in both inhibiting the ...progression of diseases and facilitating pathogenesis, so it is critical to elucidate the mechanisms regulating individual components of the autophagy machinery under various conditions. Here, we examined whether ULK1 complex component autophagy-related protein 101 (ATG101) is downregulated via ubiquitination, and whether this in turn suppresses autophagy activity in cancer cells. Knockout of ATG101 in cancer cells using CRISPR resulted in severe growth retardation and lower survival under nutrient starvation. Transfection of mutant ATG101 revealed that the C-terminal region is a key domain of ubiquitination, while co-immunoprecipitation and knockdown experiments revealed that HECT, UBA and WWE domain containing E3 ubiquitin protein ligase 1(HUWE1) is a major E3 ubiquitin ligase targeting ATG101. Protein levels of ATG101 was more stable and the related-autophagy activity was higher in HUWE1-depleted cancer cells compared to wild type (WT) controls, indicating that HUWE1-mediated ubiquitination promotes ATG101 degradation. Moreover, enhanced autophagy in HUWE1-depleted cancer cells was reversed by siRNA-mediated ATG101 knockdown. Stable ATG101 level in HUWE1-depleted cells was a strong driver of autophagosome formation similar to upregulation of the known HUWE1 substrate WD repeat domain, phosphoinositide interacting 2 (WIPI2). Cellular survival rates were higher in HUWE1-knockdown cancer cells compared to controls, while concomitant siRNA-mediated ATG101 knockdown tends to increase apoptosis rate. Collectively, these results suggest that HUWE1 normally serves to suppress autophagy by ubiquitinating and triggering degradation of ATG101 and WIPI2, which in turn represses the survival of cancer cells. Accordingly, ATG101-mediated autophagy may play a critical role in overcoming metabolic stress, thereby contributing to the growth, survival, and treatment resistance of certain cancers.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Macroautophagy (autophagy) is believed to maintain energy homeostasis by degrading unnecessary cellular components and molecules. Its implication in regulating cancer metabolism recently started to ...be uncovered. However, the precise roles of autophagy in cancer metabolism are still unclear. Here, we show that autophagy plays a critical role in glutamine metabolism, which is required for tumor survival. Pancreatic ductal adenocarcinoma (PDAC) cells require both autophagy and typical glutamine transporters to maintain intracellular glutamine levels. Glutamine deprivation, but not that of glucose, led to the activation of macropinocytosis-associated autophagy through TFEB induction and translocation into the nucleus. In contrast, glutamine uptake increased as a compensatory response to decreased intracellular glutamine levels upon autophagy inhibition. Moreover, autophagy inhibition and glutamine deprivation did not induce cell death, while glutamine deprivation dramatically activated apoptotic cell death upon autophagy inhibition. Interestingly, the addition of α-ketoglutarate significantly rescued the apoptotic cell death caused by the combination of the inhibition of autophagy with glutamine deprivation. Our data suggest that macropinocytosis-associated autophagy is a critical process providing glutamine for anaplerosis of the TCA cycle in PDAC. Thus, targeting both autophagy and glutamine metabolism to completely block glutamine supply may provide new therapeutic approaches to treat refractory tumors.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The major drawbacks of RNA sequencing (RNA-seq), a remarkably accurate transcriptome profiling method, is its high cost and poor scalability. Here, we report a highly scalable and cost-effective ...method for transcriptomics profiling called Bulk transcriptOme profiling of cell Lysate in a single poT (BOLT-seq), which is performed using unpurified bulk 3'-end mRNA in crude cell lysates. During BOLT-seq, RNA/DNA hybrids are directly subjected to tagmentation, and second-strand cDNA synthesis and RNA purification are omitted, allowing libraries to be constructed in 2 h of hands-on time. BOLT-seq was successfully used to cluster small molecule drugs based on their mechanisms of action and intended targets. BOLT-seq competes effectively with alternative library construction and transcriptome profiling methods.
The constituents and antioxidant activities of
Cyperus exaltatus
var.
iwasakii
(CE) have not been studied to date. In this study, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ...2,2′-azino-bis(3-ethylbenzothiazoline-6 sulfonic acid) (ABTS) assays were used to evaluate the radical-scavenging activities of the ethanol extract, four fractions, and isolated compounds of CE. In addition, phenolic acids and flavonoids were isolated from the ethanol extract of CE using column chromatography. The compounds identified by spectroscopy were gallic acid, protocatechuic acid, vanillic acid,
p
-coumaric acid, rutin, ferulic acid, isoquercitrin, astragalin, quercetin, luteolin, apigenin, tricin, and kaempferol. Quantitative analysis using high-performance liquid chromatography (HPLC) revealed that the major flavonoids of CE were astragalin and tricin and that the major phenolic acid was
p
-coumaric acid. In addition, comparative analysis of CE from Ganghwa and Hampyeong habitats using HPLC showed that the Hampyeong CE had a higher phytochemical content. Comparative analyses of the isolated compounds were also conducted among five
Cyperus
species. The highest antioxidant activities were found in the ethyl acetate (EtOAc) fraction, and among the compounds isolated from CE, vanillic acid and quercetin showed remarkable antioxidant activity even when compared with ascorbic acid. The results demonstrate the usefulness of CE, which has not been sufficiently studied previously, and will facilitate the evaluation of its potential effectiveness as antioxidant functional plant material.
This paper presents a class <inline-formula><tex-math notation="LaTeX">\Phi_{2}</tex-math></inline-formula> inverters for high-power applications using multiple enhancement-mode gallium nitride ...(eGaN) switching devices operating at 13.56 MHz. The eGaN devices are beneficial in high-frequency, high-power applications such as plasma processing, thanks to the low switching and conduction losses. In addition, the small size of eGaN devices increases power density while reducing the impact of parasitic package components. However, their small package size makes it challenging to manage power dissipation, particularly at higher frequencies where additional conduction losses due to dynamic <inline-formula><tex-math notation="LaTeX">R_{DS(on)}</tex-math></inline-formula> and switching losses due to <inline-formula><tex-math notation="LaTeX">C_{OSS}</tex-math></inline-formula> can significantly increase power dissipation. To address these challenges, we investigate the individual contributions of dynamic <inline-formula><tex-math notation="LaTeX">R_{DS(on)}</tex-math></inline-formula> and <inline-formula><tex-math notation="LaTeX">C_{OSS}</tex-math></inline-formula> to power losses at high frequencies by paralleling multiple devices. We also propose criteria for selecting the optimum number of parallel eGaN devices to decrease power dissipation per device by reducing conduction losses greater than the addition in <inline-formula><tex-math notation="LaTeX">C_{OSS}</tex-math></inline-formula> losses. This approach helps to alleviate thermal stress in the devices. Finally, we demonstrate the effectiveness of our approach by designing a 1 kW single inverter and a 2 kW push-pull inverter at 13.56 MHz, which achieve over 90% drain efficiency while reducing thermal stress in the device.
Abscisic acid (ABA) is a plant hormone that plays a significant role in various developmental and physiological processes in higher plants. In this study, ABA was quantified in Chamaecyparis obtusa, ...Pinus rigida × Pinus taeda, and Pinus densiflora seeds stored for 20 years at −18 °C, 4 °C, or 25 °C using high-performance liquid chromatography. At all temperatures, C. obtusa had the highest ABA concentration, followed by P. rigida × P. taeda and then P. densiflora. The germination rates of the seeds were also investigated. For the two Pinus species, there was an inverse relationship between ABA content and germination rate. However, as all C. obtusa seeds failed to germinate, no such correlation was observed for this species. This study provides important information for advancing ABA research in gymnosperms, which may provide insight into their physiological and biochemical mechanisms.
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