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Comparative assessment of immunochromatographic test kits using low-molecular-weight antigens from cyst fluids of two different genotypes of
No full textHuman cysticercosis is a serious zoonosis caused by infection with larvae (cysticerci) of the pork tapeworm, Taenia solium. Infection can involve the nervous system, causing chronic headache and intracranial hypertension, focal neurological deficits, epileptic seizures, and paralysis. The disease is found in developing countries, where porcine cysticercosis is prevalent and undercooked pork is habitually consumed. This study aimed to develop immunochromatography-based test (ICT) kits, using low-molecular-weight antigens purified from cyst fluids of Latin American and Asian genotypes of T. solium. To evaluate the kits, we used 164 serum samples, including 24 from proven/confirmed cysticercosis cases, 110 from cases with other parasitoses, and 30 from healthy individuals. Diagnostic performances were calculated. The sensitivity, specificity, and accuracy were 83.3% (95% CI [62.6–95.3]), 93.6% (95% CI [88.1–97.0]), and 92.1% (95% CI [86.8–95.7]), respectively for the American genotype-based ICT kit, while for the Asian genotype-based ICT kit, they were 87.5% (95% CI [67.6–97.3]), 98.6% (95% CI [94.9–99.8]), and 97.0% (95% CI [93.0–99.0]), respectively. The sensitivity and specificity did not significantly differ between the two ICT kits (exact McNemar’s test; p > 0.05), with a concordance of 93.9%, represented by a Cohen’s kappa of 0.77 (p < 0.001), indicating substantial agreement. These results indicate that affinity-purified antigens from different geographical isolates can be used for the diagnosis of human cysticercosis. The diagnostic specificities were better than for a previously reported ICT kit that used crude antigen
Rôle d’une bactérie du microbiote intestinal dans l’encéphalopathie liée à la cirrhose hépatique
No full textHabitat preferences of cosmopolite ferns in lowland abandoned rice fields of Manokwari: Potential risks of population outbreak
No full textEcological studies of cosmopolite ferns are necessary to predict population explosions and potential invasions in an ecosystem. This study investigated habitat preferences, abundance, and adaptation of three cosmopolite fern species, Stenochlaenapalustris (Burm. f) Bedd., Thelypteris interrupta (Willd.) K. Iwats., and Nephrolepis biserrata (Sw.) Schott in abandoned lowland rice fields in Sidey District, Manokwari Regency, West Papua Province, Indonesia. Field observations were conducted using vegetation analysis with quadrats. The results showed that the abundance of S. palustris, T. interrupta, and N. biserrata was 76 ± 12, 77 ± 14, and 57 ± 9 individuals/m2, respectively. The study revealed that S. palustris and T. interrupta preferred open habitats with high light intensity, high moisture, and acidic soils (pH < 5), whereas N. biserrata had distinct habitat preferences. Multivariate analysis showed that environmental factors explained 93.7% of the data variation, and habitat-sharing was observed between S. palustris and T. interrupta. These findings suggest that S. palustris and T. interrupta, which prefer open habitats and acidic soils, may be able to invade abandoned rice fields. This study provides insights into the ecological adaptations of these fern species and their potential invasions
Spatio-temporal monitoring of mangrove biodiversity using Landsat-8 imagery in Kendari Bay, Indonesia
No full textMangrove ecosystems are key biodiversity hotspots that provide critical habitats for various coastal species, enhance carbon sequestration, and contribute to the overall ecosystem resilience. However, these ecosystems are becoming increasingly vulnerable to anthropogenic pressures, leading to significant degradation. This study examined the spatio-temporal dynamics of mangrove ecosystems in Kendari Bay, Southeast Sulawesi, Indonesia, from 2020 to 2024, using multi-temporal Landsat-8 imagery. Normalized Difference Vegetation Index (NDVI) analysis was applied to assess vegetation health as a proxy for mangrove biodiversity and canopy vigor, and supervised classification was used to map land cover change. The results indicate a substantial increase in critically degraded mangrove areas, from 13.2% in 2020 to 31.7% in 2024. These changes signify a decline in habitat quality [and spatial fragmentation of biodiversity-rich zones] associated with mangrove ecosystems. These findings underscore the urgency of strengthening conservation measures, ecological zoning, and restoration efforts to maintain biodiversity and ensure sustainable coastal ecosystem services. The integration of NDVI, land-cover classification, and degradation mapping provides a reliable framework for monitoring mangrove biodiversity in rapidly urbanizing tropical coasts. Remote sensing analysis, as demonstrated in this study, offers valuable insights into monitoring mangrove health and supporting biodiversity conservation strategies
Analysis of A Predator-Prey Model with The Effects of Threshold Harvesting
No full textThis study develops and analyzes a predator-prey model within an extended Lotka-Volterra framework that incorporates a Holling Type II functional response and a threshold-based harvesting strategy. Two ecological regimes were considered: a non-harvesting regime, where population densities remain below prescribed thresholds, and a harvesting regime activated once these thresholds are exceeded. The analysis begins with the identification of equilibrium points, followed by a local stability analysis using the Jacobian matrix and eigenvalue criteria. In the absence of harvesting, three biologically meaningful equilibria are obtained: trivial, semitrivial, and interior equilibria representing prey-predator coexistence. The stability of these equilibria depends on key biological parameters, such as predator mortality and prey intraspecific competition. When threshold harvesting is introduced, the interior equilibrium can be stabilized if the harvesting thresholds are chosen appropriately. Numerical simulations confirm that threshold-based harvesting may stabilize dynamics that are unstable in the non-harvesting case, although this effect is highly sensitive to harvesting parameters and exploitation intensity. The results highlight the importance of well-designed threshold harvesting policies for sustainable ecosystem management and long-term prey-predator coexistence
Utilisation of Remote Sensing and Geographic Information Systems for Mapping Potential Areas to Develop Agroforestry in Wonosobo Regency
No full textAgroforestry mapping plays a crucial role in land management and environmental sustainability, particularly in the context of increasing climate change and land degradation. This study aimed to identify the potential areas for agroforestry development. The methodology involves processing spatial and non-spatial data from multiple sources such as Planetscope 2024 imagery, Digital Elevation Models, rainfall data, and information on underdeveloped villages. The criteria for identifying potential agroforestry areas were based on land-use functions, erosion hazard index, canopy density, forest conditions, and village characteristics. These parameters were overlaid to delineate priority and non-priority areas for agroforestry development. The resulting priority map indicated that the main potential areas were located in the western part of the district. The total extent of priority areas is 43.57 hectares, comprising 1.57 hectares for priority 1, 38.1 hectares for priority 2, and 3.9 hectares for priority 3. This study contributes to effective environmental planning by enhancing food security, biodiversity, and ecosystem services through agroforestry practices
A predictive framework for realistic star-planet radio emission in compact systems
No full textContext. Radio emission from star-planet interactions (SPIs) beyond our Solar System has yet to be firmly detected, primarily due to weak signals, directional beaming effects, and low-frequency emissions blocked by Earth’s ionosphere. Addressing these obstacles calls for strategic target selection.
Aims. This proof-of-concept study aims to improve SPI target prioritization by simulating SPI-induced radio emission frequencies and estimating associated radio power to identify systems that are most likely to produce detectable signals.
Methods. We combined Zeeman–Doppler Imaging (ZDI) maps with 3D magnetohydrodynamic (MHD) stellar wind simulations and used the ExPRES code to model SPI-driven radio emissions. We also estimated the intensity of these emissions using the radio-magnetic scaling law, based on the magnetic field and plasma density parameters from the 3D wind models. We applied this approach to systems such as Tau Boo, HD 179949, and HD 189733 to assess their detectability with current and future radio telescopes.
Conclusion. This framework, tested on benchmark systems, is applicable to any star-planet system with available ZDI maps and wind models. As magnetic field reconstructions and wind simulations improve, the method will become more robust. It provides a data-driven approach to prioritize targets and optimize telescope scheduling. This approach will enable systematic exploration of magnetic SPI radio emissions across a wide range of exoplanetary systems
Chromosphere of the quiet sun
No full textContext. The solar chromosphere is a dynamic and crucial interface between the solar interior and its interplanetary environment, regulating how energy is locally deposited into heat and transported into the upper atmospheric layers. Despite significant observational and theoretical progress, the dominant processes responsible for chromospheric heating remain debated, particularly under quiet-Sun (QS) conditions.
Aims. We aim to disentangle and quantify the respective roles of shocks and current sheets (CSs) in QS chromospheric modelling.
Methods. We use a convection-zone-to-corona simulation performed with the radiation-magnetohydrodynamics code Bifrost. In order to identify shocks and CS events across space and time, we develop and apply physics-based criteria, allowing us to describe their dynamics and evaluate their contributions to both dissipative (viscous and ohmic) and mechanical (including compressive work) heating.
Results. Shocks are found to dominate the energy deposition in the lower chromosphere (1 ≲ z ≲ 1.5 Mm), accounting for up to 59% of the mechanical heating rate near z = 1.2 Mm. In contrast, CSs become the primary contributor in the upper chromosphere (1.5 ≲ z ≲ 2.5 Mm), as both plasma β and Mach number Ma drop. Overall, 66% of the mechanical chromospheric heating is powered by the combined action of shocks and CSs, with 13% emerging from regions where shocks and CSs overlap, underscoring the pivotal role of dynamic coupling in the chromosphere.
Conclusions. These results support a multi-process view of chromospheric heating in the QS, dominated by shocks, CSs, and non-steep gradient dynamics. In addition to viscous and ohmic dissipation, compressive heating can play a major role locally in the model, particularly in chromospheric shock structures, where it non-reversibly offsets cooling from expansion and radiation, and therefore constitutes a key heating contribution to consider in the energy budget. This study further highlights the need for next-generation observations to resolve the intermittent and small-scale nature of chromospheric dynamics, in order to bring new constraints on the coupling between the different layers of the solar atmosphere
Quorum colorings of perfect trees
No full textA partition π = {V1, V2, …, Vk} of the vertex set V of a graph G into k color classes Vi, with 1 ≤ i ≤ k is called a quorum coloring of G if for every vertex v ∈ V, at least half of the vertices in the closed neighborhood N[v] of v have the same color as v. The maximum cardinality of a quorum coloring of G is called the quorum coloring number of G and is denoted by ψq(G). A quorum coloring of order ψq(G) is a ψq-coloring. In this paper, we determine the exact value of the quorum coloring number of all perfect trees and show that this value is computable in linear time. Moreover, we design a linear-time algorithm that finds a ψq-coloring for any perfect tree, which partially answers an open question raised by Hedetniemi et al. [AKCE Int. J. Graphs Comb. 10 (2013) 97–109]