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Resolving white dwarf binaries within globular clusters with LISA
No full textContext. Globular clusters (GCs) around the Milky Way (MW) are expected to host white dwarf (WD) binaries emitting gravitational waves that could be detectable by LISA.
Aims. Our aim is to investigate whether LISA has the capacity to resolve WD binaries in GCs well enough in terms of sky location and distance that they can be distinguished from binaries in the MW disc.
Methods. We used a sample of 20 of the most massive GCs around the MW and simulated LISA’s sky location and distance measurement errors for WD binaries in these GCs using the software package GWToolbo
Trends in the Development of Agriculture in Karakalpakstan
No full textThe article analyses the development trends of the main agricultural crops of the Republic of Karakalpakstan. During the studies, the irrigation system in the region, thirty-year climatic features, types of land used in agriculture, the dynamics of changes in cultivated areas and product cultivation in 2012-2022 were studied. In addition, the provision of certain types of agricultural products according to the per capita ration was studied. According to the results of the analysis, it was found that the development of agriculture in the region is much lower than its existing potential. This process has a negative impact on the social and economic development of the studied area. As a result of the reforms implemented in order to reduce the problem of food insecurity in the region, it became known that the cultivated areas of potatoes, melons, and vegetables have increased in the following years. Despite this, cotton and wheat remain in the leading position in agriculture
Effects of Drying Methods on Moisture Reduction and Phenolic Content of Kepok Banana Peel (
No full textThe high moisture content of kepok banana peel (Musa paradisiaca), a nutrient-rich by-product, limited its direct use as substrate for black soldier fly larvae (BSFL). This study aimed to evaluate the effects of three drying methods: air drying (P1); oven-drying at 40°C (P2); and oven-drying at 60°C (P3), on the moisture reduction, moisture ratio (MR), and total phenolic content (TPC) of banana peels over six days. Moisture content was determined using a two-stage gravimetric oven-drying method, MR was modeled using the Page equation, and TPC was determined using Folin-Ciocalteu method. All treatments began with similar initial moisture content (86.41%) and phenolic content (134.84 mg GAE/g). P3 reached the optimal BSFL substrate moisture range (64.77%) by day 3 but continued drying to 3.93% by day 6, requiring rehydration. P1 and P2 reached the target moisture range more gradually by day 6 (60.63% and 63.43%), show better energy efficiency. P1 and P2 preserved most phenolics, while P3 drying caused a >90% loss. These findings suggest that air drying, low-temperature, or short-duration high-temperature drying treatments could optimize substrate preparation for BSFL while preserving functional compounds
Dépenses de santé et recours aux soins des hommes et des femmes
No full textLes dépenses de santé, engagées par les hommes et les femmes au cours de la vie, dépendent en premier lieu de leur état de santé et de leurs besoins de soins spécifiques. Leur situation économique et sociale, leurs préférences individuelles et les normes sociales genrées contribuent également à expliquer des différences dans leur recours aux soins et dans leurs dépenses de santé. Cet article propose un aperçu de la littérature en économie et en épidémiologie afin d’illustrer les différences de dépenses de santé et de recours aux soins entre les hommes et les femmes aux différents âges de la vie. Les dépenses de santé sont analysées sous l’angle des comportements sociaux et économiques, notamment en ce qui concerne les effets de genre, au-delà des besoins de soins spécifiques propres à chaque sexe
Farmer-Owned Enterprises (BUMP) as an Adoption of Short Food Supply Chains in Urban Areas
No full textLong food supply chains pose a challenge to the food system in urban areas. The adoption of short food supply chains (SFSC) by Farmer-Owned Enterprises (BUMP) in Semarang City provides a viable alternative solution, although gaps in understanding remain. This study aims to analyze the institutional development, role implementation, and sustainability plans of BUMP in the food supply chain. Using a qualitative approach with in-depth interviews, observations, and documentation from 11 informants— including BUMP directors, government agencies, and partners—data were analyzed using the Miles and Huberman model with triangulation validation. The results show that BUMP LSS is a farmer economic institution transformed from a farmer institution that plays a role in providing affordable food for consumers by shortening the food supply chain. Strengthening price stability and controlling inflation is carried out by BUMP LSS through synergy programs such as Pak Rahman, Lumpangsemar, Kios Pandawa Kita, and Kempling Semar. However, challenges in BUMP's SFCS implementation are sluggish traditional market players and farmer regeneration. The conclusion of this study is that BUMP is able to adopt SFSC, thus impacting the sustainability of the food system. Suggestions for further research compare urban, suburban, and rural BUMPs on SFSC adoption capabilities
Enhanced thermo-mechanical performance of TiB₂-reinforced CF/PEEK composites processed by high-temperature compression moulding
No full textCarbon fiber reinforced poly-ether-ether-ketone (CF/PEEK) composites were fabricated using a high-temperature compression moulding process, and the influence of titanium diboride (TiB₂) nanoparticles (0–4 wt%) on their thermo-mechanical performance was evaluated. The process enabled effective filler dispersion and consolidation at elevated moulding temperatures (350–370 °C). Compressive strength tests performed on CF/PEEK specimens with 2 wt% TiB2 reinforcement revealed maximum values of 201.5 MPa at 370 °C. The addition of TiB₂ primarily enhanced hardness and thermal behaviour. Rockwell hardness improved slightly with temperature and the values at different combinations (0-4wt%) TiB₂ reinforcement were discussed. SEM analysis confirmed uniform TiB₂ distribution and stronger fibre–matrix–filler bonding, while microstructural voids remained a limiting factor. Thermal studies showed excellent stability, with TGA indicating degradation onset above 550 °C and 65% char residue at 800 °C. DSC confirmed the semi-crystalline nature as both Tg (288 °C) and Tm (345 °C) were recorded, thus confirming the fact that stable crystallization of the hybrid composite has occurred. Overall, the findings prove that compression moulding at high temperature enhances CF/PEEK densification and bonding, besides promoting improvement in hardness and thermal resistance due to the presence of TiB₂. In case there is some further process optimization to reduce porosity, then TiB₂-reinforced CF/PEEK composites show strong prospects as lightweight, high-performance material for aerospace, automotive, and high-temperature structural applications
Investigating the optimal biogas yield through anaerobic co-digestion of poultry manure and cassava peels: Experimental and modelling methods
No full textAnaerobic digestion (AD) is a promising solution for sustainable energy, supporting affordable, clean power and aligning with UN Sustainable Development Goal 7. The study addressed the need for alternative energy sources through the co-digestion of poultry droppings (PD) and cassava peelings (CP). This approach is crucial for effective waste management and reducing reliance on fossil fuels. The work aimed to explore the anaerobic co-digestion of PD and CP and its effects on kinetic parameters and biogas production. Five digesters (A: 0% CP, B: 25% CP, C: 50% CP, D: 75% CP, E: 100% CP) were set up under mesophilic conditions. Results showed that digester B produced the highest cumulative biogas yield (25.2 L/gVS), with an average methane yield of 62.6%. The modified Gompertz model revealed notable differences in the kinetic parameters among the digesters, indicating that digester B had the fastest acclimation time of 6.9 days. This study has direct implications for achieving the African Union Agenda 2063, which emphasizes energy self-sufficiency through sustainable practices and supports renewable energy initiatives, especially in rural African communities. It provides valuable insights for policymakers seeking to incorporate bioenergy solutions into national energy strategies
Effect of heat treatment on the microhardness of Ti-6Al-4V alloy fabricated by laser powder bed fusion and its prediction using machine learning
No full textLaser Powder Bed Fusion process of Additive manufacturing has evolved as a game-changing technology for creating highly sophisticated components for automotive, aerospace and medical applications. The impact as well as contribution of LPBF parameters, such as laser power as a source of energy, exposure time and hatch space in developing microhardness for Ti-6Al-4V alloy is explored using a Taguchi-based design of experiments. By employing an orthogonal array, the number of required experimental runs were reduced to nine by ensuring efficient parameter optimization. This study examines the post-processing effect of heat treatment on microhardness of Ti6Al4V alloy specimen, measured using Vickers hardness testing machine. Results obtained have demonstrated a notable hardness improvement after annealing which attributed to microstructural homogenization, reduced porosity and defect mitigation. Among the heat- treated samples, laser power emerged as the most influential parameter, with sample 4S (350 W laser power, 40 µs exposure time, 0.09 mm hatch spacing) achieving the highest microhardness of 543 HV, representing a 20.9% increase over as-built conditions. In the second phase, machine learning algorithms were implemented to develop predictive models of microhardness. The highest accuracy achieved by Random Forest with R2=0.91 and Cat boost with R2= 0.93 for as build and heat-treated samples respectively. Significant insights into process optimisation and property prediction of Ti-6Al-4V produced using LPBF are offered by this integrated experimental - computational approach
Exploring the microstructural and mechanical response of aluminum composites reinforced with SiN: A novel hybrid microwave sintering approach
No full textThis study investigates the microstructural and mechanical behavior of AA7075 aluminum matrix composites reinforced with varying weight percentages (1–8 wt%) of silicon nitride (SiN), processed via high- energy ball milling and hybrid microwave sintering. Microstructural characterization revealed uniform SiN dispersion and strong matrix–particle interfaces up to 6 wt%, while higher loadings led to agglomeration. Mechanical testing demonstrated significant improvements in tensile strength (149 MPa), compressive strength (237 MPa), and hardness (107 HV) at 6 wt% SiN, attributed to Orowan looping, load transfer, grain refinement, and Zener pinning mechanisms. Beyond this threshold, reinforcement agglomeration adversely affected performance. The results confirm that hybrid microwave sintering is a viable and energy-efficient route for producing high-strength aluminum-based composites, with 6 wt% SiN identified as the optimum reinforcement level
Comparative analysis of microstructural segmentation techniques on SEM and optical micrographs
No full textSince grain morphology, distribution, and interfaces have significant effects on mechanical and functional properties, accurate microstructural characterization is still indispensable to materials research. The segmentation of Al+SiC nanocomposites using backscattered electron SEM images and the segmentation of Al-Zn-Mg powder metallurgy alloys using optical micrographs are compared in this paper. This comparison, rather than reporting material-specific results, attempts to present a broader methodological perspective by trying to distill general insights into how various imaging modalities drive algorithmic choices. These accuracy aspects are not revisited here because both have already shown high accuracy in automated segmentation and grain boundary detection. Rather, focus is on how image modality, preprocessing specifications, segmentation pipelines, and post-processing techniques interact to determine the robustness, flexibility, and possible transferability of automated microstructural analysis workflows