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Safety-related investigations designing a soluble-boron-free small modular reactor core at equilibrium
No full textMany water-cooled SMRs (WC-SMRs) are being developed and their deployment is being considered in different countries world-wide, with some designs considering no soluble boron in the coolant. The elimination of soluble boron in the coolant of WC-SMRs offers advantages such as an enhanced negative moderator temperature coefficient, reduced corrosion, and simplified chemical systems, etc. leading to the growing interest in Soluble-Boron-Free (SBF) SMR-designs. Without soluble boron, excess reactivity control relies on burnable absorbers and control rods, potentially increasing power peaking factors and requiring careful core design to ensure safety margins. This study starts with an academic SBF Karlsruhe Small Modular Reactor (KSMR) core designed with a fresh fuel loading in order to find an optimal equilibrium cycle following a two-batch refueling strategy by optimizing fuel enrichment, burnable absorber rod configuration, and Gd2O3 content using CASMO5 and SIMULATE5. A Golang-based tool, named CoreOptimizer, was developed to automate the input file generation, simulation execution and output data extraction, enabling efficient core optimization. The resulting core design meets safety and performance criteria. This paper describes the optimization process, the applied tools and discusses the key neutronic and safety characteristics of the optimized equilibrium core design
Inflammation biomarker and physical exercise: A bibliometric study
No full textPhysical exercise is widely recognized not only for its role in improving physical fitness and functional capacity, but also for its significant impact on various biological systems, including the immune response and inflammation. This study aims to determine research trends on inflammatory biomarkers and physical exercise over a 10-year period. Data collection was conducted based on the Scopus database. The database was then visualized using the VosViewer program. Based on a bibliometric analysis of 667 publications on inflammatory biomarkers and physical exercise from 2015 to 2025, the most research trends were found in 2024 with 84 publications, followed by 2018 with 79 publications and 2019 with 71 publications. Mapping the development of research publications based on keywords (co-occurrence) related to the relationship between physical activity and inflammation is in 8 clusters, while based on authors there are 6 author clusters consisting of 38 items. Co-citation analysis shows Cohen J and Statistical Power appear most prominently in the middle and are the brightest in color, indicating that these references are highly cited or have strong links with other sources. This research can be a consideration in determining research related to inflammatory biomarkers and physical activity
The role of physical activity in enhancing mental health: A scoping review of the evidence
No full textPhysical activity is increasingly recognised as a practical, low-cost strategy to protect and improve mental health. This scoping review maps and summarises recent evidence linking physical activity (including structured exercise and everyday movement) with mental health and mental ill-health outcomes across populations. We synthesised findings from high-level evidence (umbrella reviews, systematic reviews, and meta-analyses) alongside selected primary studies, including work by Hasmyati (Faculty of Sports Science and Health, Universitas Negeri Makassar) describing psychosocial and cognitive outcomes relevant to mental health (e.g., self-efficacy, concentration, and mental toughness). Across the evidence base, higher physical activity is consistently associated with lower risk of depression and anxiety, and exercise interventions show meaningful reductions in symptoms of depression, anxiety, and psychological distress. Benefits appear across age groups and clinical and non-clinical populations, although effects vary by activity type, intensity, and context (e.g., leisure-time versus occupational activity). Proposed mechanisms include neurobiological (neurotransmitters and inflammation), psychological (mastery, self-efficacy), and social (connection and support) pathways. Evidence gaps remain regarding low- and middle-income settings, long-term adherence, domain-specific measurement, and intervention tailoring. Overall, the literature supports positioning physical activity as a core component of mental health promotion and as an adjunct treatment option within stepped-care models
Extra modes in helium-core-burning stars probing an infra core cavity
No full textContext. Dipole mixed modes observed in the oscillation pattern of red giant stars probe the radiative regions in the stellar core.
Aims. Oscillation spectra of helium-core-burning stars sometimes show extra peaks that remain unexplained by the dipole mixed-mode pattern expected from the coupling of a radiative cavity in the stellar core and a pressure cavity in the stellar envelope.
Methods. We use the asymptotic expansion developed for a multi-cavity star in order to characterize these extra peaks.
Results. The analytical resonance condition of the multi-cavity gravito-acoustic modes, with two inner gravity cavities and an outer pressure cavity, helps us explain that the apparent extra peaks are dipole mixed modes that follow the three-cavity oscillation pattern. The derivation of the two asymptotic period spacings associated with the two distinct regions in the radiative core provides an estimate of the full radiative cavity.
Conclusions. Our results provide new constraints for analyzing the overshoot or mixing in the core of helium-core-burning stars. An important structure discontinuity inside the radiative core may explain the larger than expected observed period spacings
First direct electron temperature measurement in [O
No full textWe present new precise measurements of the electron temperatures and oxygen abundances in the southeast knot of I Zw 18, one of the most metal poor blue compact dwarf galaxies known. We used spectroscopic data from the Dark Energy Spectroscopic Instrument Data Release 1 (DESI DR1). For the first time in I Zw 18, we directly measured the electron temperature in the low-ionization zone using the rarely detected [O I
Integrating Molecular Dynamics and Machine Learning for Sustainable FeNiCrCoAl High-Entropy Alloys Development
No full textThe accelerating global demand for critical minerals, driven by clean energy technologies and climate goals, presents urgent sustainability challenges in materials design. High-entropy alloys (HEAs), particularly FeNiCrCoAl, offer a promising alternative by enabling reduced reliance on critical elements such as Ni, Cr, and Co. This study introduces a data-driven framework that integrates molecular dynamics (MD) simulations with artificial intelligence (AI), specifically machine learning (ML), to predict and optimize the mechanical performance of FeNiCrCoAl HEAs. MD simulations generated over 1800 datasets capturing ultimate tensile strength (UTS) across diverse compositions and temperatures. These data were used to train the Random Forest ML models, achieving high predictive accuracy (R2 = 0.975, RMSE = 0.22). Explainable AI techniques revealed Ni as a key contributor to strength, enabling targeted reduction of Co, Cr, and Al. A novel composition was discovered that reduced critical element content by over 50% achieving nearly double the UTS while retaining more than 90% of its tensile strength across the temperature range. This integrated MD-ML approach provides a scalable and sustainable pathway for alloy design, bridging atomic-scale simulation with predictive modeling to address global resource efficiency goals
Eco-Efficient Nickel: Heap Leaching as a Game-Changer for Indonesia’s Nickel Industry
No full textIndonesia, home to the world’s largest nickel laterite reserves, plays a vital role in global stainless steel and EV battery supply chains. Traditionally dominated by energy and capital-intensive pyrometallurgical methods (RKEF and BF), the industry has recently introduced hydrometallurgical HPAL technology to meet EV battery demand. However, both methods are environmentally burdensome and leave parts of laterite reserves unutilized, fueling Indonesia’s image as a “dirty nickel” producer. Heap leaching offers a compelling alternative: a low-cost, scalable, and eco-efficient hydrometallurgical process well- suited to Indonesia’s tropical laterites and low-grade ores. It improves ore utilization, reduces emissions and operational costs, and generates more stable tailings suitable for rehabilitation or use as plantation media. The process also enables recovery of by-products like magnesium sulfate, supporting circular economy practices and unlocking new revenue. Operational flexibility allows heap leaching to produce nickel for both stainless steel and battery-grade markets. Compared to conventional methods, it offers advantages in emissions, water use, waste management, economics, and local knowledge transfer. Embracing this technology could redefine Indonesia’s nickel sector, positioning the country as a leader in clean and responsible mineral extraction
Geometallurgical and Kinetic Controls on Cyanidation of a Mildly Refractory Low-Sulfidation Epithermal Gold Ore: Insights from the Mount Muro System, Indonesia
No full textGold (Au) and silver (Ag) are commonly co-extracted from low-sulphidation epithermal (LSE) ores by alkaline cyanidation, yet their dissolution behaviors often diverge despite close mineralogical association. This study investigates Au–Ag cyanidation in ore from the Mount Muro LSE deposit, Central Kalimantan, Indonesia, through integrated mineralogical characterization, diagnostic leaching, time-resolved cyanidation, residue analysis, and kinetic modeling. Diagnostic leaching indicates that ~80% of Au is cyanide-accessible at P₈₀ ≈ 75 μm, whereas only ~54% of Ag occurs in free-milling domains, with the remainder hosted in sulfide and Cu–Ag sulfosalt phases. Continuous cyanidation confirms this contrast: Au dissolves rapidly and reaches a plateau of ~87% recovery, while Ag extraction proceeds more gradually to ~78%. Residue analysis shows that unrecovered Au and Ag are concentrated in fine fractions (<38 μm), demonstrating control by mineralogical locking, partial passivation, and micro-scale diffusional barriers rather than reagent insufficiency. Shrinking Core Model diagnosis identifies mixed kinetic control for Au and diffusion-dominated control for Ag. Despite differing dominant mechanisms, kinetic model discrimination shows that both metals are best described by the Ling model, capturing non-linear, accessibility-controlled dissolution. These results highlight evolving surface accessibility as the primary control on cyanidation performance in mildly refractory LSE ores
A study on the flotation properties of a new sustainable frother based on cellulose and short-chain alcohol mixtures
No full textAmong the major challenges facing the mineral processing industry is the simultaneous need to increase productivity while reducing environmental impact. This study explores the potential of polymer- surfactant (PS) mixture composed of short-chain alcohols combined with hydroxypropyl methyl cellulose (HPMC) as a new environmentally friendly frother produced from sustainable sources. Ethanol, pentanol, and octanol were evaluated as surfactant fraction due to their availability and relatively low cost, alongside the polyglycol based commercial frother (Dowfroth 200) as a benchmark. The result demonstrates that longer-chain alcohols are more effective at preventing bubble coalescence, longer-chain alcohol achieving unimodal distributions at lower concentrations. Interestingly, HPMC exhibited unique behavior due to its macromolecular structure, forming a stable yet slow-diffusing layer around bubbles, resulting in bimodal distributions even at higher concentrations. Mixtures of HPMC and alcohols, particularly pentanol and octanol, show synergistic effects that enhance the initial stabilization of the air-liquid interface, facilitating unimodal distributions at relatively low concentrations. These findings offer valuable insights for optimizing frother formulations to improve flotation efficiency
Effect of Solvent Ratio of
No full textThe research aimed to determine the effect of solvent ratio of Phaleria macrocarpa fruit on the extracted yield, chemical contents and antimicrobial activity for Escherichia coli and Salmonella sp. The materials used were Phaleria macrocarpa fruit and aquadest. The extraction method used in this study was Ultrasound-Assisted Hydro-distillation Extraction (UAHDE). The antimicrobial activity was detected by the inhibition zone of Phaleria macrocarpa fruit extract against Lactic Acid Bacteria, Escherichia coli and Salmonella sp. using the well diffusion method. The results showed that with an extract ratio of 1:2 produced a yield of (87.3 ml), 1:4 (362 ml), and 1:6 (486 ml). The results of the chemical test of Phaleria macrocarpa showed that extract ratio 1:2 (phenol 314.64 mg GAE/100g and flavonoid 39.89 mg EQ/100g), 1:4 (phenol 228.02 mg GAE/100g and flavonoid 21.61 mg EQ/100g), 1:6 (phenol 150.89 mg GAE/100g and flavonoid 15.35 mg EQ/100g). Comparison of the ratios of 1:4 and 1:6 showed significant results (P<0.05) inhibition of Salmonella sp. bacteria with an inhibition zone of 1.1 ± 0.2mm and Escherichia coli of 1±0.0mm, while no inhibition was detected for Lactic Acid Bacteria. It can be concluded that the extract of the Phaleria macrocarpa fruit have the potential to be used as a feed additive for poultry