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Advancing Quantitative Phase Imaging for Biological Studies using Single-Shot Transport-of-Intensity Equation and Beam Splitting Assemblies
No full textQuantitative phase imaging is a technique to extract the phase information of the transparent sample being investigated. One
quantitative phase imaging technique is the transport of intensity equation (TIE), which is a non-interferometric method that relates the intensities as a function of position with the phase. Current trends in this technique are by doing single-shot, which does not require any mechanical translation. Thus, improving its efficiency in capturing images. In these studies, a wollaston prism was used to split the beams with optical glass plate placed on one beam to induce a controlled defocus. On the second part of the study, the technique is implemented using a lateral displacement beam splitter. This technique allows quantitative phase imaging with the advantage of a single-shot measurementDocto
Discovery of Diphenyl Ether Derivatives as Novel BKCa Channel Activators: Structure-Activity Relationship, Cryo-EM Complex Structures, and In Vivo Animal Studies
No full textThe BKCa channel, a large-conductance calcium-activated potassium channel, plays a crucial role in maintaining the homeostasis of the micturition cycle and airway-related functions. In this study, we optimized a novel BKCa channel activator, 4d, with a diphenyl ether structure identified from library screening. This led to the discovery of potent activators, 10b (EC50 = 0.12 μM, cell-based assay) and 51b, an orally bioavailable derivative. Compound 10b demonstrated potent in vivo efficacy in a spontaneous hypertensive rat (SHR) of urinary incontinence model, while compound 51b showed dose-dependent cough suppression efficacy with an ED50 of 11.8 mg/kg in a citric acid-induced cough model. Furthermore, we reported the cryo-electron microscopy (cryo-EM) structures of the BKCa channel in complex with 10b and 51b at resolutions of 2.8 and 3.4 Å. Based on structural analyses, we determined the binding sites and key interaction residues of 51b, which were validated via mutation studies. © 2025 American Chemical Society.FALSEsciescopu
Self-powered ultraviolet photodetectors based on sub-100 nm nonstoichiometric β-Ga2O3−δ thin films: role of oxygen vacancies in carrier transport
No full textWe report on the performance of ultraviolet (UV) photodetectors based on nonstoichiometric β-Ga2O3−δ thin films with a thickness of 65 nm. The epitaxial Ga2O3−δ films were deposited on sapphire (0001) substrates by radio-frequency powder sputtering at 500 ℃. The oxygen-deficient, nonstoichiometric nature of the films was confirmed by hard X-ray photoelectron spectroscopy. The fabricated metal-semiconductor-metal photodetectors exhibited a photo-to-dark-current ratio of 2.17 × 102, photoresponsivity of 136.15 A W−1, and specific detectivity of 5.06 × 1013 Jones at 10 V under 254 nm UV illumination. Self-powered operation was achieved, yielding a photocurrent of ~0.6 nA at a nominal zero bias. Biexponential fitting of the time-resolved response revealed slow decay components attributed to oxygen-vacancy-related traps. These results indicate that the oxygen vacancies play a dual role by enhancing the photocurrent through free-carrier generation and contributing to persistent photoconductivity. Our findings demonstrate promising potential of sub-100 nm nonstoichiometric β-Ga2O3−δ thin films for high-performance UV photodetectors. © 2025 Elsevier B.V., All rights reserved.FALSEsciescopu
Reconstructive Spectrometers: Hardware Miniaturization and Computational Reconstruction
No full textSpectrometers serve as indispensable analytical tools across chemistry, materials science, environmental monitoring, medical diagnostics, and beyond. The emergence of reconstructive spectrometers represents a transformative leap in spectral analysis, combining miniaturized encoding hardware with advanced computational algorithms to revolutionize conventional approaches. These devices encode unknown spectral data into measurable signals, for which sophisticated algorithms then decode to reconstruct the original spectrum with high fidelity-all achieved within an ultra-compact footprint. In this review, we first establish the mathematical foundations governing spectral encoding and decoding. We then provide a detailed analysis of encoding strategy and state-of-the-art decoding techniques, followed by recent breakthroughs in hardware design for optimized spectral reconstruction systems. Finally, we address key challenges and future opportunities, offering insights into how reconstructive spectrometers may redefine spectroscopy beyond traditional laboratory settings.TRUEsciescopu
Ginsenoside-Re-rich ethanol extract of Panax ginseng berry enhances healthspan extension via mitostasis and NAD metabolism
No full textBackground
Ginseng Berry Concentrate (GBC) enhances exercise capacity in mice, but the effects of its key component, ginsenoside Re (G-Re), on aging and mitochondrial function are not well understood. This study investigates the impact of G-Re on mitophagy and its potential to promote healthy aging.
Methods
Experiments in C2C12 myocytes and HeLa-mitoKeima-PARKIN cells assessed GBC and G-Re's effects on mitophagy, supported by Gene Set Enrichment Analysis. G-Re was identified as the primary component of GBC via high-performance liquid chromatography. The influence of G-Re on lifespan and healthspan was examined in Caenorhabditis elegans, with a focus on mitophagy pathways.
Results
GBC and G-Re significantly induced mitophagy and enhanced mitochondrial gene expression, improving mitochondrial function. G-Re extended lifespan and healthspan in C. elegans, effects absent in mitophagy-impaired mutants.
Conclusion
G-Re enhances mitochondrial function and promotes healthy aging through mitophagy, suggesting its potential for mitigating age-related functional declines.TRUEsciescopuskcikci_cand
Structure of MICU from non-metazoan Dictyostelium discoideum reveals unique characteristics
No full textIn most eukaryotes, the mitochondrial calcium uniporter (MCU) mediates Ca2+ influx into the mitochondrial matrix through a process regulated by MICUs and the EMRE. In Dictyostelium discoideum, a model organism for amoebozoans that lack an EMRE, the MCU complex consists solely of the MCU and MICU. Most likely, therefore, the mechanism by which DdMICU regulates the DdMCU differs from the extensively studied metazoan MCU-EMRE-MICU system. Here, we report the crystal structure of Ca2+-bound DdMICU at 2.5 & Aring; resolution. Unlike human MICUs, which contain two Ca2+-binding EF-hand motifs, DdMICU possesses three EF-hand motifs, each with a submicromolar Ca2+ binding affinity. The overall structure of DdMICU is comparable to that of human MICUs, and their well-conserved dimer interface interactions are similar. In addition to the face-to-face dimer observed in human MICUs, DdMICU forms a head-to-head dimer with multimeric states that equilibrate between tetrameric and dimeric forms, depending on the solution ionic strength. Moreover, the C-helix of DdMICU plays a critical role in membrane binding. These findings provide a molecular basis for the unique mechanism regulating Ca2+ uptake by MICUs in an EMRE-free system and offer insight into the evolution and functional diversity of the MCU complex in non-metazoan organisms.TRUEsciescopu
Metastable photo-induced superconductivity far above Tc
No full textInspired by the striking discovery of metastable superconductivity in K3C60 at 100K, far above Tc = 20 K, we discuss possible mechanisms for long-lived, photo-induced superconductivity. Starting from a model of optically-driven Raman phonons coupled to inter-band electronic transitions, we develop a microscopic mechanism for photo-controlling the pairing interaction. Leveraging this mechanism, we first investigate long-lived superconductivity arising from the thermodynamic metastable trapping of the driven phonon. We then propose an alternative route, where the superconducting gap created by an optical drive leads to a dynamical bottleneck in the equilibration of quasi-particles. We conclude by discussing the implications of both scenarios for experiments that can be used to discriminate between them. Our work provides falsifiable explanations for the nanosecond-scale photo-induced superconductivity found in K3C60, while simultaneously offering a theoretical basis for exploring metastable superconductivity in other quantum materials. © The Author(s) 2025.TRUEsciescopu
Analysis of Co-Optimization of Energy and Reserve Considering Reserves Cascading; [예비력의 순차적 확보(Reserves Cascading)를 고려한 에너지와 예비력의 동시 최적화 연구]
No full textThis study investigates the impact of Reserve Cascading on electricity market efficiency, with a particular focus on energy prices, reserve prices, and total generation costs across scenarios defined by different reserve requirements. Reserve Cascading allows surplus higher-tier reserves to be reallocated to meet lower-tier demands, optimizing generator dispatch, reducing reliance on additional resources, and enhancing overall market stability. The analysis reveals that energy and reserve prices exhibit notable fluctuations depending on the reserve requirements of each scenario. Despite these price variations, Cascading consistently demonstrates its ability to lower total generation costs across all scenarios by minimizing generator dispatch needs and improving operational efficiency. The study highlights the value of integrating Cascading into electricity market design as a strategic tool to enhance economic efficiency and market reliability. Copyright © The Korean Institute of Electrical Engineers.FALSEscopuskc
Microscopic Heterogeneity Driven by Molecular Aggregation and Water Dynamics in Osmolyte-Water Mixtures
No full textLiving organisms have small organic compounds called osmolytes to modulate protein stability and structure. Numerous experimental and computational works have been performed to understand the mode of action of osmolyte, but their operating mechanism is still inconclusive. The direct mechanism, one of the two primary hypotheses, suggests that protecting osmolytes are likely to be excluded from the protein surface, while the destabilizing osmolytes preferentially form intermolecular interaction with protein molecules. The indirect mechanism focuses on the modulation of water hydrogen bond structure and dynamics in the presence of osmolytes. Herein, we employed a combination of molecular dynamics simulation with graph theory and microheterogeneity measurement in four osmolyte-water binary solutions of dimethylsulfoxide (DMSO), trimethylamine-N-oxide (TMAO), tetramethylurea (TMU), and urea to clarify the operating mechanism of osmolyte on protein stability. The protecting osmolyte, TMAO does not form noticeable self-association aggregates and uniformly distributed even at the microscopic level. On the other and, the destabilizing osmolyte TMU readily associates with neighboring osmolyte molecules, resulting in microheterogeneity of TMU-water solutions. Furthermore, we investigated the water dynamical properties, translational and rotational motion and H-bond lifetime of water in the two representative binary mixtures, TMAO-water and TMU-water mixtures. The translational and rotational motions of water are more significantly retarded in TMAO-water mixtures, exhibiting fully homogeneous distribution, than microscopically heterogeneous TMU-water mixtures. The H-bond lifetime of TMAO-water is much longer than that of TMU-water, which means the protecting osmolyte TMAO forms more tight binding with water molecules. As a result, TMAO has less chance to interact with protein, and TMU is more likely to make hydrophobic interaction around protein surfaces. Taken together, we suggest that the both direct and indirect mechanisms work in combination that encompasses the direct intermolecular interaction between osmolyte and protein and indirect interaction through the alteration of water H-bond network and dynamical properties in osmolyte aqueous solutions.MasterAbstract ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․. i
List of contents ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ ii
List of figures ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ iv
I. INTRODUCTION ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 1
II. ANALYSIS METHODS ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․. 4
2. 1. Radial Distribution Function ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 4
2. 2. Graph Theoretical Analysis ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 4
2. 3. Aggregate Size Distribution ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 5
2. 4. h-value ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․. 5
2. 5. Water Dynamical Properties ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ ․․․․․․ 6
2. 5. 1. Translational Motion of Water ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 6
2. 5. 2. Reorientational Motion of Water ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․.․․․․․․․․ 7
2. 5. 3. H-bond Lifetime ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 7
2. 5. 4. Retardation Factor ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․. 8
III. MOLECULAR AGGREGATION AND MICROHETEROGENEITY ․․․․․․․․․․. 9
3. 1. Introduction ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․.․ 9
3. 2. Computational Details ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 9
3. 3. Result and Discussion ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․.․ 10
IⅤ. MICROHETEROGENEITY AND WATER DYNAMICS ․․․․․․․․․․․․․․․․․․․․․․․․․. 20
4. 1. Introduction ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 20
4. 2. Computational Details ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․.․․․ 20
4. 3. Result and Discussion ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․ 21
Ⅴ. CONCLUSION ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․. 33
References ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․.․. 34
Curriculum Vitae ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․.․. 41
Acknowledgements ․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․․. 4
Cross-talks between Metabolic and Translational Controls during Beige Adipocyte Differentiation
No full textWhether and how regulatory events at the translation stage shape the cellular and metabolic features of thermogenic adipocytes is hardly understood. In this study, we report two hitherto unidentified cross-talk pathways between metabolic and translational regulation in beige adipocytes. By analysing temporal profiles of translation activity and protein level changes during precursor-to-beige differentiation, we found selective translational down-regulation of OXPHOS component-coding mRNAs. The down-regulation restricted to Complexes I, III, IV, and V, is coordinated with enhanced translation of TCA cycle genes, engendering distinct stoichiometry of OXPHOS and TCA cycle components and altering the related metabolic activities in mitochondria of thermogenic adipocytes. Our high-resolution description of ribosome positioning unveiled potentiated ribosome pausing at glutamate codons. The increased stalling is attributable to remodelled glutamate metabolism that decreases glutamates for tRNA charging during pan-adipocyte differentiation. The ribosome pauses decrease protein synthesis and mRNA stability of glutamate codon-rich genes, such as actin cytoskeleton-associated genes. © The Author(s) 2025.TRUEsciescopu