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Rapid formation of a very massive star (>50000 M
No full textContext. We present simulations of a massive young star cluster using the codes Nbod
Beyond monoculture: Polydisperse moment methods for sub-stellar atmosphere cloud microphysics
No full textContext. Understanding how the shape of cloud particle size distributions affects the atmospheric properties of sub-stellar atmospheres is a key area to explore, particularly in the JWST era of broad wavelength coverage, where observations are sensitive to particle size distributions. It is therefore important to elucidate how underlying cloud microphysical processes influence the size distribution, in order to better understand how clouds affect observed atmospheric properties.
Aims. In this follow-up paper, we aimed to extend our sub-stellar atmosphere microphysical cloud formation framework to include effects of assuming a polydisperse gamma particle size distribution, requiring a three-moment solution set of equations.
Methods. We developed a three-moment framework for sub-stellar mineral cloud particle microphysical nucleation, condensation, evaporation, and collisional growth assuming a gamma distribution. As in our previous work, we demonstrated the effects of polydispersity using a simple 1D Y-dwarf KCl cloud formation scenario, and compared the results with the monodisperse case.
Results. Our three-moment scheme provides a generalised framework applicable to any size distribution with a defined moment generation expression. In our test case, we showed that the gamma distribution evolves with altitude, initially broad at the cloud base and narrowing at lower pressures. We found that differences between the gamma and monodisperse cloud structures can be significant, depending on the surface gravity of the atmosphere.
Conclusions. We presented a self-consistent framework for including the effects of polydispersity for sub-stellar microphysical cloud studies using the moment method
LOFAR uniqueness under extreme ionospheric conditions: The May 2024 Mother’s Day superstorm
No full textThe May 2024 Mother’s Day superstorm, the strongest since November 2003, triggered significant ionospheric disturbances. Indeed, during the superstorm, the ionosphere above Europe was transformed into a severely depleted, super-high-altitude plasma structure extending beyond 1500 km above Earth’s surface. We highlight the unique contributions of the LOw Frequency ARray (LOFAR) to ionospheric weather research on this extreme event. Originally designed for radio astronomy, LOFAR’s extensive European network of 52 stations and wide-band capabilities enable high-resolution ionospheric monitoring at both local and regional scales. Leveraging LOFAR measurements, we characterise a plethora of ionospheric effects that occurred during the main and early recovery phases of the storm. We did this by observing significant signal fading associated with the equatorward expansion of the auroral oval during the main phase and by capturing high-speed moving ionospheric irregularities (up to ~800 m/s), and quantifying extreme ionospheric uplift (up to 1500 km) under conditions where conventional HF instruments were not usable due to the occurrence of D-layer absorption, ionospheric G-conditions and uplift above ionosonde altitude range. In this investigation, we harness the unique capabilities of LOFAR to direct view into the structure and dynamics of the ionosphere under the most extreme space weather conditions. Our results confirm LOFAR as an insightful instrument for ionospheric research, offering critical capabilities for advancing storm impact assessment, forecasting, and mitigation strategies
Polarization camera based fringe locking system for scanning beam interference lithography
No full textA fringe displacement during the exposure process in scanning beam interference lithography (SBIL) systems leads to wavefront errors in linear gratings. The exact orientation of the fringe pattern along the scan direction is also essential for the production of high-quality gratings. In this paper, we report on the development of a fringe stabilization system with a separate measuring beam, which can precisely determine the fringe movement during the exposure of the photoresist and simultaneously record the orientation of the fringe pattern. This is specifically designed to minimize low-frequency phase errors originating in the lithography writing head itself, which can be a dominant source of instability independent of the stage positioning. Using polarization camera based phase-shifting interferometry, we determine the phase offset between the two interfering beams in real time, and thus reduce the fringe movement to single-digit nanometers by moving a piezo-actuated mirror. In addition, we can use the area-based phase measurement to align the setup and track the rotation of the fringe spot during exposure. In combination with a nano positioning and measuring machine, a fringe observation system was implemented that can precisely record the fringe displacement in the substrate plane. This allows the performance of the fringe stabilization system to be quantified
Nature-based solutions as an approach to empower community in programming Curug Kulon green space
No full textNature-based solution (NBS) has become tools to improve environmental resilience and reduce temperature increases due to global climate change. Although many green spaces are still underutilized and have little ecological, social, or economic value, they are essential to this mission. At the same time, previous research has established NbS as an integrated framework for environmental management, climate adaptation, and its practical implementation, particularly in urban contexts. This study examines the case of Curug Kulon in Tangerang Regency, where green spaces are neglected and only marginally used for urban agriculture. Through land potential analysis and Focus Group Discussions with local stakeholders, the study identified key strategies for programming green spaces based on the socio-cultural characteristics of the community. The results demonstrate (1) the possibility of creating multipurpose land uses, (2) the conversion of local residents into proactive promoters and advocates of environmental conservation, and (3) the incorporation of green space functions as educational areas, productive landscapes, and ecological buffers. Research recommends a participatory framework to improve climate resilience based on community empowerment by developing urban green space program and provides a concept of green space sustainable management
The development of suburban housing: Between needs and sustainability challenges
No full textThe development of suburban housing by developers continues to increase along with population growth and the need for affordable housing. This phenomenon provides economic opportunities but also poses serious challenges in the context of sustainable development. This study adopts a descriptive-qualitative research design, focusing on the case of Jakarta's suburban buffer zone to examine development patterns, spatial transformations, and emerging sustainability issues. This study analyzes how suburban housing development practices meet the principles of sustainable development, including environmental, social, and economic aspects. Previous research findings show that many developers focus on physical expansion without considering land conservation, water resource management, and efficient transportation connectivity. The impacts are fragmentation of natural habitats, increased carbon emissions, and reduced quality of life due to lack of public facilities and green open spaces. However, several innovative projects have begun to adopt the concept of green cities with a sustainable spatial approach, use of environmentally friendly materials, and integration of social infrastructure. The findings indicate that although some improvements have emerged, suburban housing development remains insufficiently aligned with sustainability principles, particularly in terms of transit integration, equitable access, and long-term environmental resilience. This study emphasizes the importance of government regulation, developer awareness, and community participation in encouraging more inclusive and sustainable housing development. With the right approach, suburban housing development can not only meet housing needs but also support environmental sustainability and long-term social welfare
Modelling the Effects of Dynamic Parameters of a Self-Balancing Electric Segway over Irregular Sinusoidal Terrains
No full textDynamic modelling and advanced control analysis are employed to investigate the behavior of a self-balancing electric Segway navigating on irregular sinusoidal terrains. A nonlinear dynamic model treats the Segway as a cart–inverted pendulum system, incorporating sinusoidal road irregularities and elastic and damping interactions at the wheel–ground interface. Equations of motion are derived using the Lagrangian formulation and linearized around equilibrium with Taylor expansions. Numerical simulations via the fourth-order Runge–Kutta method reveal significant increases in vibration amplitudes and system sensitivity at higher speeds. Kernel Density Estimation (KDE) is applied to translational and angular vibration data, yielding smooth distributions, while Lorenz-like attractors indicate deterministic chaos under certain excitations. Stability is assessed through bifurcation analysis, which reveals a critical forward velocity of 20.102 m/s, beyond which the system transitions into instability. The findings also identify critical thresholds, including a friction-to-mass ratio above approximately 7, a gravity-to-length ratio exceeding 25, and a mass ratio near 0.3. Each of them contributes to heightened instability and complex oscillatory responses. The significant influence of irregular terrain on system dynamics underscores the necessity for robust control strategies to maintain operational stability and rider comfort on uneven surfaces
The effect of adding green concentrate based on
No full textThe study evaluated the effect of Azolla pinnata and Spirulina platensis-based green concentrates on quail (Coturnix japonica) egg quality. A completely randomized design was employed with three treatments: P0 (control), P1 (10% Azolla), and P2 (10% Azolla + 0.1% Spirulina), each with five replicates. Results indicated that while egg weight and Haugh Unit remained unaffected (p>0.05), yolk colour score was significantly enhanced (p<0.05) in P2 compared to the control. The study This study concludes that the strategic combination of 10% Azolla pinnata and 0.1% Spirulina platensis effectively enhances quail egg yolk pigmentation without compromising egg weight or internal quality. These findings imply that this green concentrate formulation offers a viable, natural nutritional strategy for poultry producers to improve egg marketability by meeting consumer preferences for deeper yolk colour, potentially adding economic value without relying on synthetic pigments
Growth and carcass responses of broiler chickens to dietary inclusion of
No full textPolyalthia longifolia, originally a plant from India and commonly known in Indonesia as
glodokan tiang, is a widely cultivated ornamental tree characterized by its tall growth and short branches. The plant contains various bioactive compounds including alkaloids, steroids, tannins, and saponins, which are associated with improved growth performance, feed efficiency, and meat quality in livestock. Additionally, its flavonoid content has been reported to stimulate appetite, regulate feed intake, and enhance pigmentation. This study was conducted to evaluate the effect of incorporating
P. longifolia leaf meal into broiler rations. The experiment, carried out for five weeks at the Faculty of Animal Husbandry, University of Jambi, involved 200 day-old chicks allocated to four dietary treatments: P0 (0% leaf meal), P1(2%), P2 (4%), and P3 (6%). A completely randomized design with four treatments and five replicates was applied, and the collected data were analyzed using analysis of variance. The results demonstrated that inclusion of
P. longifolia leaf meal significantly decreased slaughter weight, carcass weight, and abdominal fat percentage, whereas no significant difference was observed in relative carcass weight. In conclusion, supplementation of up to 2%
P. longifolia leaf meal in broiler diets did not adversely affect slaughter weight, carcass yield, relative carcass weight, or abdominal fat percentage
Response of Sugarcane (
No full textPolychar plus granules grade B are a synergistic formulation of carbon-rich biochar, enriched goat manure, and inorganic fertilizers (1:2:1/2), packaged in granular to increase nutrient availability and rehabilitate degraded land. This study examined the effects of different application rates of this granule on soil chemical properties and the early growth of sugarcane seedlings. The experiment was carried out from July to October 2025 using two sugarcane varieties, Cenning (V1) and NXI-4T (V2), and four fertilizer doses: P0 (control), P1 (125 g/polybag), P2 (250 g/polybag), and P3 (375 g/polybag). Growth parameters were evaluated using ANOVA followed by an LSD test at the 5% level. Application of 125 g/polybag (P1) significantly increased soil potassium availability and resulted in higher plant height and leaf number in the NXI-4T variety at 42 days after planting. No significant effects were observed at other growth stages or on tiller formation. Higher doses (P2 and P3) tended to reduce growth likely due to reduced nutrient uptake efficiency. Overall, the results indicate that a moderate dose of Polychar Plus Granule can effectively replace up to 50% of inorganic fertilizer without reducing sugarcane seedling performance, offering a promising option for sustainable sugarcane nursery management