Earticle

This study focuses on isolating and characterizing novel polyhydroxybutyrate (PHB) depolymerase-producing bacteria to enable efficient PHB biodegradation. PHB is a promising biodegradable alternative to petroleum-based plastics, requires PHB depolymerase to facilitate its effective depolymerization and mineralization in the environment. We identified Janibacter terrae COS4-44 from oil contaminated tidal flat in Taean, Republic of Korea, demonstrating high PHB degradation efficiency via clear zone formation and enzymatic activity. Scanning electron microscopy (SEM) revealed increased surface roughness and porosity in degraded PHB films, while Fourier-transform infrared spectroscopy (FTIR) confirmed the cleavage of ester bonds, indicating enzymatic breakdown. The PHB depolymerase gene was successfully cloned and expressed in E. coli, yielding a functional 58 kDa enzyme. Optimal degradation conditions were 40°C, pH 8.0, and 96 h incubation, with 0.15% PHB concentration. Glucose and yeast extract enhanced enzyme activity, whereas heavy metals like Zn²⁺ and Co²⁺ slightly stimulated depolymerase production. These findings highlight Janibacter terrae COS4-44 as a potent PHB degrader, offering potential for sustainable plastic waste management. Further research on degradation metabolites and enzyme engineering could enhance industrial applications.

Anthraquinones are secondary metabolites of plants and are widely distributed in vari-ous species. They are known to exhibit a wide range of biological activities, including anticancer, anti-inflammation, antioxidant, antibacterial, anti-damage, and anti-osteoporosis. Anthraquinones are generally lipophilic, which results in relatively low solubility and bioavailability. These limita-tions can be addressed through enzymatic reactions such as glycosylation and hydroxylation. In this study, we attempted the glycosylation of two anthraquinone compounds, anthraflavic acid and xanthopurpurin, using microbial UDP-glycosyltransferase UGT-1. UGT-1 could catalyze the O-glu-cosylation of anthraquinones to form glucoside-type products, which were confirmed by HPLC and high-resolution LC-MS analyses. This study demonstrates that glycosyltransferase UGT-1 could be a good candidate for producing modified anthraquinones with poogical activtential biolities

Trehalose is a naturally occurring disaccharide that is abundantly present in nature. Its presence in cells as several effects, especially because it acts as a natural defender of proteins and membranes. It is utilized in food, cosmetics, and medications because of its excellent water retention properties. Following its esterification with fatty acids of different chain lengths, trehalose has also been shown to have anti-bacterial, anti-biofilm, and anti-inflammatory properties. Trehalose plays a structural part in the bacterial cell wall’s adaptive reactions to stressors including osmotic variations high temperature. Additionally, it was proposed that when bacterial cells are exposed to harsh environment challenges such as heat, cold, desiccation, or reactive oxygen species, these organisms biosynthesize high concentrations of both intra- and extracellular trehalose to help them to survive. Therefore, we analyzed Variovorax sp. PAMC28711 isolated from Antarctica, which was predicted by bioinformatics tools (RAST, Prokka, KEGG, CGView Server, and MetaCyc) to predict the enzymes involved in the different pathways of trehalose production. Furthermore, TLC analysis was carried out to characterize various trehalose biosynthesis pathways. According to the findings, it was revealed that our polar bacteria Variovorax sp. PAMC28711 have potential to produce trehalose through three (Trehalose-6 phosphate synthase/trehalose-6-phosphat phosphatase, Trehalase synthase, and Maltooligosyl-trehalose synthase/maltooligosyl-trehalose trehalohydrolase) pathways. We anticipate that this strain could be of potential use for manufacturing trehalose on the industrial scale.

The term “sweet spot” is commonly used in analog/RF engineering to describe an operating region where multiple, often competing, requirements are satisfied simultaneously. This paper presents a practical sweet-spot framework that treats bias selection as a constrained multi-objective problem and explicitly connects device inversion level to distortion, noise, power/current, bandwidth-related loading, and robustness against process-voltage-temperature (PVT) drift. A step-by-step, equation-based analysis is given for IM3 shaping using a main path and an auxiliary path that controls the IM3 amplitude ratio and phase error at a combining node, clarifying how a “dip” in IM3 can be created and widened into a tunable sweet-spot region. Finally, a sweet-spot-aware parallel-path architecture is proposed to make the sweet spot tunable and repeatable under realistic excitation.

We are trying to apply surface stress improvement process (SSIP) to the repair and maintenance of nuclear power components, mainly in the United States and Japan. A representative example is applying water jet peening (WJP) and laser peening (LP) technology to parts to extend their lifespan. The biggest problem with the lifespan of nuclear power equipment is the occurrence of stress corrosion cracking (SCC), which is directly related to safety. The SSIP is one of the good ways to mitigate SCC. The Code Case N-931 “Performance and Qualification Criteria for Mitigation of Stress Corrosion Cracking by Surface Stress Improvement: Section III, Division 1 and 3’ was developed since 2017 by the task group “Advanced Surface Stress Improvement Technology” in Korea International Working Group (KIWG) of the American Society of Mechanical Engineers (ASME). This case provides performance and qualification criteria for the pre-service application of a SSIP to items potentially susceptible to SCC, as a means to prevent crack initiation. Mitigation of items to the requirements of this case does not modify or change the in-service inspection (ISI) requirements for those items. This Code Case is to be used for SSIP such as ultrasonic nanocrystal surface modification (UNSM), WJP, LP that satisfy the performance criteria and qualification criteria defined in this case. Two major technical bases for this Code Case are “PVP2022-85151” and “EPRI Report 3002018458”. Brief summary of UNSM technology and two technical bases is introduced.

This study proposes a methodology to interpret cylindrically propagating elastic waves as analogous to waves propagating in Cartesian coordinates. By employing coordinate transfor-mations and leveraging the symmetry of wave propagation, the approach simplifies the complexi-ties inherent in cylindrical coordinate systems. This framework enables the application of existing Cartesian-based analytical techniques to cylindrical wave problems, providing enhanced computa-tional efficiency. The proposed method holds potential for various engineering applications, includ-ing elastic wave-based nondestructive testing and structural optimization, particularly in complex media and structures.

Preventive medicine aims to promote health by investigating and researching the distribution of health and health-related risk factors. The desired life time of the small modular reactor (SMR) being developed as a new energy source is more than 100 years. Improving the problems of key components such as stress corrosion cracking (SCC) and corrosion fatigue of the SMR structures and erosion and fretting fatigue of turbine blades improves the service life of the SMR. Also, in bearings, it improves wear and rolling/sliding contact fatigue. It is necessary to develop a proactive maintenance program prior to design to ensure that the SMR and bearing systems can be shut down after operation within their designed lifespan. Similar to preventive medicine, proactive maintenance programs applied to the SMR and bearing systems must undergo advance inspection. This ensures that the characteristics of key components do not deteriorate or exceed predetermined standards. Additionally, it is necessary to develop and standardize technology that restores the characteristics of key components to their designed performance state. In this paper, we introduce the concept of prognostic inspection and proactive maintenance (PIPM) system with ultrasonic nanocrystal surface modification (UNSM) and suggest a method of applying PIPM to SMR and bearing systems.

Historically minimized as an artifact of data corruption or suboptimal sensing, stochastic noise is undergoing a paradigm shift across the cognitive and computational sciences. Traditional deterministic frameworks have treated noise as a strict limitation—an error term to be eliminated to minimize empirical risk. This thought paper challenges the elimination paradigm by examining the functional role of noise in two primary fields: machine learning and neuroscience. We trace the conceptual evolution of noise from ongoing epistemic inquiries regarding its physical nature to pragmatic inquiries regarding its algorithmic utility. In neuroscience, empirical findings of trial-by-trial neuronal and behavioral variability have revealed that the brain actively leverages non-deterministic variance for exploration and predictive coding. In machine learning, the injection of noise has evolved from a structural regularizer preventing catastrophic overfitting in descriptive models into the generative “sampling seed” of modern probabilistic architectures. Ultimately, by applying Ashby’s Principle of Requisite Variety, this paper posits that intelligent systems do not merely tolerate environmental variance; they actively internalize noise as a functional mechanism to perceive, predict, and generalize within an unpredictable world.

This article explores interreligious dialogue as a key tool for peacebuilding in post-conflict African societies. It employs a hermeneutical-philosophical lens to advocate for an ethics of understanding as the basis for healing and reconciliation. Drawing on the philosophical perspectives of Hans-Georg Gadamer and African ethical traditions, the study highlights how dialogical engagement across religious and cultural lines can foster mutual recognition and restore dignity to affected communities. It emphasizes the importance of narrative, memory, and meaning in shaping interreligious ethics. By advancing a transformative approach to dialogue, the article challenges instrumental views of religion and calls for deeper epistemological shifts in peacebuilding practices on the continent.