Changwon National University

Valeriana fauriei and V. dageletiana are traditional medicinal plants known for their calming effects and use in alleviating insomnia. However, genomic information for these species is limited. This study aimed to sequence and characterize the complete chloroplast genomes of V. fauriei and V. dageletiana, and to compare them with those of closely related Valeriana species to investigate structural variation, molecular evolution, and divergence history. The chloroplast genomes of V. fauriei, V. dageletiana, and V. jatamansi were highly conserved in overall structure. Minor differences were observed in tandem repeat regions and sequence divergence hotspots, particularly within accD, rps18, and the trnN–trnL intergenic region. Analysis of 57 protein-coding genes from four species revealed that most genes are under strong purifying selection. However, elevated dN/dS ratios in psbI, rps7, and rpl23 suggest potential lineage-specific divergence. Phylogenetic reconstruction showed that V. fauriei and V. dageletiana form a clade with V. officinalis, whereas V. jatamansi is an earlier diverging lineage. Divergence time estimation indicated that V. officinalis split from this clade 0.4255 to 1,0839 million years ago, and that V. fauriei and V. dageletiana diverged approximately 0.0205 million years ago. These results provide insights into the evolution of Valeriana chloroplast genomes, highlighting both structural conservation and species-specific variation. The findings contribute to a better understanding of recent speciation events and molecular evolution in this genus, supporting future phylogenomic and taxonomic studies of Valeriana species.

Gamma prime (γ') precipitates and grain boundary (GB) carbides govern the high-temperature performance of Ni-based superalloys, and their reliable quantification is essential for microstructural evaluation and alloy development. However, conventional etching procedures are often transferred between alloys without considering composition-dependent changes in γ' size and fraction or carbide population, which can cause unstable contrast, γ-matrix damage, and unreliable image-based interpretation. Here, we establish composition-tailored etching conditions for Haynes® 282 (γ' ~23nm) and two model alloys with modified Al-Ti and Nb-Ta contents, and evaluate their suitability for phase-selective Scanning electron microscopy (SEM) imaging. After identical mechanical preparation, γ' precipitates in Haynes® 282 and Model alloy 1 are clearly revealed using a nitric-acid etchant, whereas the same condition fails in Model alloy 2 with reduced Al and Ti, where much finer γ' precipitates form. An HF-containing mixed-acid etchant is introduced to obtain stable γ' contrast in Model alloy 2 without excessive surface relief. GB carbides also show composition-dependent responses. In Haynes® 282, Cr-rich M₂₃C₆-decorated boundaries are revealed by nitric acid, whereas Nb/Ta-containing model alloys require chloride-based etchants to expose both MC and M₂₃C₆ carbides. These protocols provide reproducible, phase-selective SEM contrast for robust image-based quantification.

ABSTRACT Monolithic III–V multijunction photovoltaics are promising candidates for both space power systems and solar‐to‐chemical energy conversion, yet their deployment in flexible, chemically aggressive, and radiation‐rich environments requires simultaneous control of epitaxial quality, conformability, and barrier properties. Here, we present a flexible InGaP/GaAs/InGaAs triple‐junction platform that addresses these requirements within a single device architecture. The optimized epitaxial stack and its growth process enable almost fully relaxed subcells with low dislocation density, supporting power conversion efficiencies above 33% under AM1.5G and ∼31% under AM0, even after transferring the epitaxial stack to a thin plastic substrate to improve mechanical compliance. To ensure environmental robustness, the flexible triple‐junction cells are encapsulated with an ultrathin glass sheet that provides strong protection against aqueous and strongly alkaline conditions, as well as against high‐energy proton and electron irradiation. By exploiting the high output voltage and durability of this platform, bias‐free electrocatalysis with formate as the predominant product is demonstrated using a simple electrocatalyst configuration. These results establish a unified III–V multijunction photovoltaic architecture that couples space‐relevant efficiency, flexibility, and radiation hardness with chemical durability suitable for unassisted solar‐to‐chemical conversion, offering a versatile route toward next‐generation terrestrial and space energy systems.

Background/Objectives: Alzheimer's disease (AD) is a progressive neurodegenerative disorder for which no disease-modifying therapy that halts or substantially slows disease progression is currently available. Although antibody therapies targeting amyloid β (Aβ) have recently received FDA approval, their high cost, limited efficacy, and potential adverse effects highlight the need for alternative solutions. Therefore, the development of low-molecular-weight compounds capable of reducing toxic Aβ aggregates is of considerable interest. In this study, we investigated the effects of 2,3,4-trihydroxybenzophenone (THB) on the inhibition and disassembly of Aβ1-42 aggregates through in vitro and in vivo experiments. Methods: In vitro assays were performed to evaluate the effects of THB on Aβ1-42 aggregation and fibril disassembly. Cell viability assays and hippocampal slice electrophysiology were conducted to assess neurotoxicity and synaptic function. In vivo effects were examined in Aβ1-42 aggregate-injected mice and in 5 Familial AD mutations (5XFAD) mice using behavioral, histological, and electrophysiological analyses. Results: THB inhibited Aβ1-42 aggregation in a concentration-dependent manner and promoted the disassembly of preformed fibrils. THB attenuated Aβ1-42-induced Neuro2a cell death and restored Aβ1-42 aggregate-associated long-term potentiation (LTP) deficits in hippocampal slices. In Aβ1-42 aggregate-injected and 5XFAD mice, THB reduced amyloid pathology and neuroinflammatory markers and improved synaptic function and memory performance. Conclusions: These findings suggest that THB modulates pathogenic Aβ1-42 assemblies and provides a structural basis for the development of small-molecule modulators of Aβ1-42 aggregation with potential preventive or disease-modifying applications in AD.